CN114008494B - Optical filter, imaging device and optical sensor - Google Patents

Abstract

The present invention relates to a filter comprising an absorption layer and a reflection layer, wherein the reflection layer comprises a dielectric multilayer film, the absorption layer comprises a transparent resin having a glass transition temperature of 130 ℃ or higher and a near infrared absorption dye (a), the difference between the average transmittance of 490nm to 560nm of the near infrared absorption dye (a) and the average transmittance of 590nm to 630nm of the transparent resin is 10% or less, the average internal transmittance of the light having a wavelength of 490nm to 560nm is 90% or more, the average internal transmittance of the light having a wavelength of 590nm to 630nm is 90% or more, and the width between the wavelengths is 180nm or more when the internal transmittance is 50% in the wavelength range of 650nm to 1150nm, and the difference between the average transmittance of 490nm to 560nm of the near infrared absorption dye (a) and the average transmittance of 490nm to 560nm of the transparent resin is 10% or less.

Description

Optical filter, imaging device and optical sensor

Technical Field

The present invention relates to a filter that transmits light in a visible wavelength range and blocks light in a near infrared wavelength range, and an imaging device and an optical sensor having the filter.

Background

In an imaging device using a solid-state imaging element, in order to satisfactorily reproduce color tone and obtain a clear image, a filter that transmits light in the visible light region (hereinafter also referred to as "visible light") and blocks light in the near infrared region (hereinafter also referred to as "near infrared light") is used. As this filter, a near infrared cut filter is known in which an absorbing layer containing a near infrared ray absorbing dye and a resin and a reflecting layer containing a dielectric multilayer film blocking near infrared light are provided on a glass substrate.

Such a near infrared cut filter is used for an ambient light sensor or the like, in which case it is required to absorb light in a specific long wavelength range of near infrared light and to have high transmittance in the visible light region.

As a filter for an ambient light sensor, for example, patent document 1 discloses a filter using a dye having an absorption capacity in a wavelength range of 850nm to 1050nm, which is a long wavelength range of near infrared light.

Patent document 2 describes a technique of a near infrared cut filter that has good absorption characteristics in the long wavelength range of near infrared light, is easily obtained in a small and thin-walled shape, is less likely to cause minute defects during polishing, and is excellent in cost and productivity, instead of an absorbing glass having absorption in the long wavelength range of near infrared light. Patent document 2 discloses the use of a dye containing a diimmonium dye, a cyanine dye andA technique for obtaining a near infrared cut filter having the above characteristics by combining a dye obtained by salt with an optical film of a transparent resin.

Prior art literature

Patent literature

Patent document 1: international publication No. 2017/094672

Patent document 2: japanese patent laid-open No. 2008-303130

Disclosure of Invention

Problems to be solved by the invention

However, the visible light transmittance of the above-mentioned filter using an absorbing layer containing a specific pigment having an absorbing ability in the long wavelength range of near infrared light and a transparent resin, particularly the transmittance of green light and red light which strongly affect visual perception, cannot be said to be sufficiently high.

The present invention provides a filter capable of effectively blocking light in a long wavelength range of near infrared light, particularly in a wavelength range of 850nm to 1100nm, and capable of maintaining sufficiently high visible light transmittance, particularly transmittance of green light and red light, and an imaging device and an optical sensor using the same.

Means for solving the problems

The optical filter according to one embodiment of the present invention comprises an absorption layer containing a near infrared ray absorption dye (a) and a transparent resin having a glass transition temperature of 130 ℃ or higher, and a reflection layer containing a dielectric multilayer film, wherein the near infrared ray absorption dye (a) satisfies all of the following requirements (1-1) to (1-6):

(1-1) in a spectral transmittance curve SC _TR having a wavelength of 350nm to 1200nm measured by including the near infrared ray absorption dye (a) in the transparent resin, a maximum absorption wavelength λ _max(A)TR is in a wavelength range of 850nm to 1100 nm;

(1-2) in the spectral transmittance curve SC _TR, when the internal transmittance at the maximum absorption wavelength λ _max(A)TR is 10%, the average internal transmittance T _{AVE490-560(A)TR} of light having a wavelength of 490nm to 560nm is 90% or more;

(1-3) in the spectral transmittance curve SC _TR, when the internal transmittance at the maximum absorption wavelength λ _max(A)TR is 10%, the average internal transmittance T _{AVE590-630(A)TR} of light having a wavelength of 590nm to 630nm is 90% or more;

(1-4) in the spectral transmittance curve SC _TR, when the internal transmittance at the maximum absorption wavelength λ _max(A)TR is 10%, having two wavelengths in which the internal transmittance is 50% in the wavelength range of 650nm to 1150nm, and a width between the wavelengths in which the two internal transmittances are 50% is 180nm or more;

(1-5) in a spectral transmittance curve SC _DCM having a wavelength of 350nm to 1200nm, measured by dissolving the near-infrared ray absorption dye (a) in methylene chloride, when the transmittance of light at the maximum absorption wavelength λ _max(A)DCM is 10%, the value obtained by subtracting the average internal transmittance T _{AVE490-560(A)TR} from the average transmittance T _{AVE490-560(A)DCM} of light at the wavelength of 490nm to 560nm is 10% or less;

(1-6) in the spectral transmittance curve SC _DCM, when the transmittance of light at the maximum absorption wavelength λ _max(A)DCM is 10%, the value obtained by subtracting the average internal transmittance T _{AVE590-630(A)TR} from the average transmittance T _{AVE590-630(A)DCM} of light at wavelengths of 590nm to 630nm is 10% or less.

The invention also provides an imaging device and an optical sensor with the optical filter.

Effects of the invention

According to the present invention, it is possible to provide a filter capable of effectively blocking light in a long wavelength range of near infrared light, particularly in a wavelength range of 850nm to 1100nm, and capable of maintaining sufficiently high visible light transmittance, particularly transmittance of green light and red light, and an imaging device and an optical sensor using the same.

Drawings

Fig. 1 is a cross-sectional view schematically showing an example of a filter according to an embodiment.

Fig. 2 is a cross-sectional view schematically showing another example of the filter of one embodiment.

Fig. 3 is a cross-sectional view schematically showing another example of the filter of one embodiment.

Fig. 4 is a cross-sectional view schematically showing another example of the filter of one embodiment.

Fig. 5 is a cross-sectional view schematically showing another example of the filter of one embodiment.

Fig. 6 is a cross-sectional view schematically showing another example of the filter of one embodiment.

FIG. 7 is a graph showing spectral transmittance curves of pigments (A1 a-5 NS) in test example 2 in transparent resin P and in methylene chloride.

FIG. 8 is a graph showing spectral transmittance curves of pigments (A1 a-5 NS) in test example 19 in a transparent resin other than transparent resin P and in methylene chloride.

Fig. 9 is a graph showing a spectral transmittance curve of an absorption layer in the filter of example (example 1; example).

Fig. 10 is a graph showing a spectral transmittance curve of the filter of the example (example 1; example).

Fig. 11 is a graph showing a spectral transmittance curve of an absorption layer in the filter of example (example 4; example).

Fig. 12 is a graph showing a spectral transmittance curve of the filter of the example (example 4; example).

Fig. 13 is a graph showing a spectral transmittance curve of an absorption layer in the filter of example (example 6; example).

Fig. 14 is a graph showing a spectral transmittance curve of the filter of the example (example 6; example).

Fig. 15 is a graph showing a spectral transmittance curve of an absorption layer in the filter of example (example 8; comparative example).

Fig. 16 is a graph showing a spectral transmittance curve of the filter of the example (example 8; comparative example).

Detailed Description

Hereinafter, embodiments of the present invention will be described.

In the present specification, the near infrared absorbing dye may be simply referred to as "NIR dye" and the ultraviolet absorbing dye may be simply referred to as "UV dye".

In this specification, the compound represented by the formula (A1) is referred to as a compound (A1). The same applies to compounds represented by other formulas. The pigment containing the compound (A1) is also referred to as pigment (A1), and the same applies to other pigments. For example, the group represented by the formula (1 x) is also referred to as a group (1 x), and the groups represented by other formulas are also similar.

In this specification, the internal transmittance means a transmittance obtained by subtracting the influence of the interface reflection from the measured transmittance, which is expressed by a formula of the measured transmittance/(100-reflectance). In the present specification, the transmittance of the transparent substrate including the resin and the transmittance of the resin layer including the pigment in the resin such as the absorption layer are all "internal transmittance" when the spectrum is described as "transmittance". On the other hand, the transmittance measured by dissolving the dye in a solvent such as methylene chloride or the like and the transmittance of the filter having the dielectric multilayer film were measured transmittance.

In the present specification, a transmittance of, for example, 90% or more for a specific wavelength range means a transmittance of not less than 90% in the entire wavelength range, that is, a minimum transmittance of 90% or more in the wavelength range. Similarly, a transmittance of, for example, 1% or less for a particular wavelength range means a transmittance of not more than 1% over the entire wavelength range, i.e., a maximum transmittance of 1% or less over the wavelength range. The same applies to the internal transmittance. The average transmittance and average internal transmittance in a specific wavelength range are arithmetic average values of transmittance and internal transmittance per 1nm in the wavelength range.

In the present specification, "to" indicating a numerical range includes an upper limit and a lower limit.

< Filter >

The filter according to one embodiment of the present invention (hereinafter also referred to as "the present filter") includes an absorption layer containing a transparent resin (hereinafter also referred to as a transparent resin (P)) having a glass transition temperature (hereinafter also referred to as "Tg") of 130 ℃ or higher and a NIR dye (a) satisfying all of the following requirements (1-1) to (1-6), and a reflection layer containing a dielectric multilayer film.

(1-1) In the spectral transmittance curve SC _TR having a wavelength of 350nm to 1200nm measured by including the NIR dye (A) in the transparent resin (P), the maximum absorption wavelength lambda _max(A)TR is in the wavelength range of 850nm to 1100 nm.

(1-2) In the spectral transmittance curve SC _TR, when the internal transmittance at the maximum absorption wavelength lambda _max(A)TR is 10%, the average internal transmittance T _{AVE490-560(A)TR} of light having a wavelength of 490nm to 560nm is 90% or more.

(1-3) In the spectral transmittance curve SC _TR, when the internal transmittance at the maximum absorption wavelength lambda _max(A)TR is 10%, the average internal transmittance T _{AVE590-630(A)TR} of light having a wavelength of 590nm to 630nm is 90% or more.

(1-4) In the spectral transmittance curve SC _TR, when the internal transmittance at the maximum absorption wavelength lambda _max(A)TR is 10%, there are two wavelengths in which the internal transmittance is 50% in the wavelength range of 650nm to 1150nm, and the width between the wavelengths in which the two internal transmittances are 50% is 180nm or more.

(1-5) In the spectral transmittance curve SC _DCM at a wavelength of 350nm to 1200nm, which is measured by dissolving the NIR dye (A) in methylene chloride, when the transmittance of light at the maximum absorption wavelength lambda _max(A)DCM is 10%, the value obtained by subtracting the average internal transmittance T _{AVE490-560(A)TR} from the average transmittance T _{AVE490-560(A)DCM} of light at the wavelength of 490nm to 560nm is 10% or less.

(1-6) In the spectral transmittance curve SC _DCM, when the transmittance of light at the maximum absorption wavelength lambda _max(A)DCM is 10%, the value obtained by subtracting the average internal transmittance T _{AVE590-630(A)TR} from the average transmittance T _{AVE590-630(A)DCM} of light at wavelengths of 590nm to 630nm is 10% or less.

The optical filter contains the NIR pigment (A) having the characteristics of (1-1) to (1-6) and the transparent resin (P) in the absorption layer, can effectively block light in the long wavelength range of near infrared light, particularly in the wavelength range of 850nm to 1100nm, and can maintain sufficiently high visible light transmittance, particularly transmittance of green light and red light. In general, it is known that NIR pigments having a maximum absorption wavelength in a long wavelength range have difficulty in reproducing high visible light transmittance in methylene chloride in a transparent resin due to association. As shown in the above-mentioned items (1-5) to (1-6), it was found that the NIR pigment (A) maintained high visible light transmittance in methylene chloride in terms of the relationship with the transparent resin (P).

The NIR dye (A) preferably further satisfies one or more, more preferably two or more, particularly preferably all of the following (1-7) to (1-9).

(1-7) The value obtained by subtracting the average transmittance T _{AVE435-480(A)DCM} of light having a wavelength of 435nm to 480nm in the spectral transmittance curve SC _DCM when the transmittance of light having the maximum absorption wavelength lambda _max(A)DCM is 10% from the average internal transmittance T _{AVE435-480(A)TR} of light having a wavelength of 435nm to 480nm in the spectral transmittance curve SC _TR when the internal transmittance at the maximum absorption wavelength lambda _max(A)TR is 10% or less.

(1-8) The value obtained by subtracting the average internal transmittance T _{AVE490-560(A)TR} from the average transmittance T _{AVE490-560(A)DCM}% or less.

(1-9) The value obtained by subtracting the average internal transmittance T _{AVE590-630(A)TR} from the average transmittance T _{AVE590-630(A)DCM}% or less.

The present filter may further have a transparent substrate. In this case, the absorption layer and the reflection layer are provided on the main surface of the transparent substrate. The present filter may have an absorption layer and a reflection layer on the same main surface of the transparent substrate, or may have an absorption layer and a reflection layer on different main surfaces. In the case where the absorption layer and the reflection layer are provided on the same main surface, the lamination order of the absorption layer and the reflection layer is not particularly limited.

The filter may also have other functional layers. Examples of the other functional layer include an antireflection layer that suppresses loss of visible light transmittance. In particular, in the case of a structure in which the absorption layer is the outermost surface, since a loss of visible light transmittance due to reflection occurs at the interface between the absorption layer and air, an antireflection layer may be provided on the absorption layer.

Next, a structural example of the present filter will be described with reference to the drawings. Fig. 1 shows an example of a structure of a filter 10A having a reflective layer 12 on one principal surface of an absorption layer 11. In the filter 10A, the absorbing layer 11 may be composed of a layer containing the NIR dye (a) and the transparent resin (P). The absorption layer 11 may further contain a NIR dye (B) and/or a NIR dye (C) described later. In this case, the absorbing layer 11 may be a multi-layered structure, and the NIR pigment (a), the NIR pigment (B), and/or the NIR pigment (C) are contained in each layer in an appropriate combination. The "having the reflective layer 12 on (on) one main surface of the absorption layer 11" is not limited to the case where the reflective layer 12 is provided so as to be in contact with the absorption layer 11, and includes the case where another functional layer is provided between the absorption layer 11 and the reflective layer 12, and the following configuration is also similar.

Fig. 2 is a cross-sectional view schematically showing an example of an optical filter of an embodiment having a transparent substrate, an absorption layer, and a reflection layer. The filter 10B has a transparent substrate 13, an absorption layer 11 disposed on one principal surface of the transparent substrate 13, and a reflection layer 12 disposed on the other principal surface of the transparent substrate 13. In the filter 10B, the absorbing layer 11 may have the same structure as that in the filter 10A.

Fig. 3 shows an example of a structure of a filter 10C having an absorption layer 11 and reflection layers 12a and 12b on both principal surfaces of the absorption layer 11. Fig. 4 shows an example of a structure of a filter 10D having an absorption layer 11 on one principal surface of a transparent substrate 13 and reflection layers 12a and 12b on the other principal surface of the transparent substrate 13 and on the principal surface of the absorption layer 11. In the filters 10C and 10D, the absorbing layer 11 may have the same structure as that in the filter 10A.

Fig. 5 is a structural example of a filter 10E having absorption layers 11a and 11b on both principal surfaces of a transparent substrate 13 and further having reflection layers 12a and 12b on principal surfaces of the absorption layers 11a and 11 b.

In fig. 3, 4 and 5, the two reflective layers 12a, 12b combined may be the same or different. For example, the following constitution is possible: the reflective layers 12a, 12b have a property of reflecting ultraviolet light and near infrared light and transmitting visible light, the reflective layer 12a reflects ultraviolet light and light in the first near infrared region, and the reflective layer 12b reflects ultraviolet light and light in the second near infrared region.

In fig. 5, at least one of the two absorption layers 11a and 11b is an absorption layer having the above-described structure in the present filter. The absorbent layers 11a and 11b may be the same or different. In the case where the absorption layers 11a and 11b are different, for example, the absorption layers 11a and 11b may be a combination of a near infrared ray absorption layer and an ultraviolet ray absorption layer, respectively, or may be a combination of an ultraviolet ray absorption layer and a near infrared ray absorption layer, respectively.

In addition, in the filter 10E, when the absorbing layers 11a and 11B contain not only the NIR dye (a) but also the NIR dye (B) and/or the NIR dye (C) described later, the NIR dyes contained in the absorbing layers 11a and 11B may be appropriately combined. For example, in the case where the filter 10E contains the NIR pigments (a) to (C), one of the absorption layers 11a and 11b may contain one selected from the NIR pigments (a) to (C) and the other may contain the other two. The absorbent layers 11a and 11b may each be a single layer or a multilayer structure.

Fig. 6 shows an example of the structure of a filter 10F having an antireflection layer 14 on the principal surface of the absorption layer 11 of the filter 10B shown in fig. 2. In the case where the reflection layer is not provided and a structure in which the absorption layer is the outermost surface is employed, an antireflection layer may be provided on the absorption layer. The antireflection layer may be a structure that covers not only the outermost surface of the absorption layer but also the entire side surface of the absorption layer. In this case, the moisture-proof effect of the absorbent layer can be improved.

Hereinafter, the absorption layer, the reflection layer, the transparent substrate, and the antireflection layer will be described.

(Absorption layer)

The absorbing layer contains an NIR dye (A) having the characteristics of (1-1) to (1-6) above, preferably further having one or more characteristics selected from (1-7) to (1-9) above, and a transparent resin (P).

The absorbing layer is typically a layer or (resin) substrate in which the NIR dye (a) is uniformly dissolved or dispersed in the transparent resin (P). The absorbing layer may contain other NIR pigments in addition to the NIR pigment (a) within a range not to impair the effect of the present invention. Further, the absorbing layer may contain pigments other than NIR pigments, particularly UV pigments, within a range not to impair the effects of the present invention.

As the other NIR dye, it is preferable that the NIR dye (B) having a maximum absorption wavelength in a wavelength range of 1100nm to 1200nm and the squaraine having a maximum absorption wavelength in a wavelength range of 630nm to 750nm are contained in a spectral transmittance curve of 350nm to 1200nm measured by incorporating the dye in the transparent resin (P)NIR pigment (C) of salt pigments. According to the required characteristics of the present filter, the absorbing layer may contain not only the NIR dye (a) but also either one of the NIR dye (B) and the NIR dye (C) or both of the NIR dye (B) and the NIR dye (C).

The absorption layer contains the NIR dye (B), whereby near-infrared light in a wavelength range longer than the absorption wavelength range of the NIR dye (a) can be absorbed, and absorption corresponding to the wavelength range of the absorption type glass can be obtained by the absorption layer. By containing the NIR dye (C) in the absorbing layer, the influence of the incident angle dependence of the reflecting layer including the dielectric multilayer film in the present filter can be reduced.

NIR pigment (A)

As specified in (1-1), the maximum absorption wavelength lambda _max(A)TR of the NIR pigment (A) is in the wavelength range of 850nm to 1100 nm. The maximum absorption wavelength lambda _max(A)TR is preferably in the wavelength range from 900nm to 1050 nm.

As defined in (1-2), the NIR pigment (A) has a T _{AVE490-560(A)TR} of 90% or more. T _{AVE490-560(A)TR} is preferably 92% or more, more preferably 94% or more. As defined in (1-3), the NIR pigment (A) has a T _{AVE590-630(A)TR} of 90% or more. T _{AVE590-630(A)TR} is preferably 91% or more, more preferably 94% or more.

As specified in (1-4), the spectral transmittance curve SC _TR of the NIR dye (a) when the internal transmittance at the maximum absorption wavelength λ _max(A)TR is 10% has two wavelengths whose internal transmittance is 50% in the wavelength range of 650nm to 1150nm, and the width W _T50％ between the wavelengths whose two internal transmittances are 50% is 180nm or more. W _T50％ is preferably 200nm or more, more preferably 300nm or more. The wavelength on the short wavelength side of the wavelengths having the internal transmittance of 50% is preferably 650nm or more, more preferably 700nm or more. The upper limit of W _T50％ is preferably about 380nm, more preferably about 370nm, and even more preferably about 320nm.

As specified in (1-5), the NIR pigment (A) has a T _{AVE490-560(A)DCM}-T_{AVE490-560(A)TR} of 10% or less, as specified in (1-6), the NIR pigment (A) has a T _{AVE590-630(A)DCM}-T_{AVE590-630(A)TR} of 10% or less, and each of T _{AVE490-560(A)DCM}-T_{AVE490-560(A)TR} and T _{AVE590-630(A)DCM}-T_{AVE590-630(A)TR} is preferably 8% or less.

Here, T _{AVE490-560(A)DCM} and T _{AVE590-630(A)DCM} are respectively the average transmittance of light having a wavelength of 490nm to 560nm and the average transmittance of light having a wavelength of 590nm to 630nm when the transmittance of light having the maximum absorption wavelength λ _max(A)DCM is 10% in the spectral transmittance curve SC _DCM having a wavelength of 350nm to 1200nm measured by dissolving the NIR dye (a) in methylene chloride. Lambda _max(A)DCM is preferably in the wavelength range of 850nm to 1100nm, more preferably in the wavelength range of 900nm to 1000 nm.

The T _{AVE435-480(A)DCM}-T_{AVE435-480(A)TR} of the NIR dye (A) as shown in (1-7) is preferably 10% or less, more preferably 9% or less, and further preferably 7% or less. The T _{AVE490-560(A)DCM}-T_{AVE490-560(A)TR} of the NIR dye (A) as shown in (1-8) is preferably 5% or less, more preferably 4% or less, and still more preferably 3% or less. The T _{AVE590-630(A)DCM}-T_{AVE590-630(A)TR} of the NIR dye (A) as shown in (1-9) is preferably 5% or less, more preferably 4% or less, and still more preferably 3% or less.

The molecular structure of the NIR dye (A) is not particularly limited as long as the requirements (1-1) to (1-6) are satisfied in terms of the relation with the transparent resin (P). Specifically, the dye is selected from cyanine dye, croconic acid dye, phthalocyanine dye, and squaraineAt least one dye selected from the group consisting of a salt dye, a diimmonium dye, a trisubstituted type iminium dye and a diketopyrrolopyrrole dye is particularly preferably a trisubstituted type iminium dye from the viewpoint of high visible light transmittance and the size of the width of the absorption layer.

The trisubstituted type ammonium sulfite pigment of the NIR pigment (a) is preferably selected from one or more compounds represented by the following formula (A1) and compounds represented by the following formula (A2).

Symbols in the formulae (A1) and (A2) are as follows.

R ²⁰¹～R²⁰⁶ and R ²²¹～R²²⁶ are each independently a hydrogen atom, a halogen atom, a sulfo group, a hydroxyl group, a cyano group, a nitro group, a carboxyl group, a phosphoric acid group, an alkyl group having 1 to 20 carbon atoms which may have an oxygen atom between carbon atoms and may be substituted, an alkoxy group having 1 to 20 carbon atoms which may have an oxygen atom between carbon atoms and may be substituted, an aryl group having 6 to 14 carbon atoms which may be substituted, an aralkyl group having 7 to 14 carbon atoms which may be substituted, or a 3-to 14-membered heterocyclic group which may be substituted. Wherein, the group having a substituted or unsubstituted amino group bonded to the phenyl group is excluded. In addition, in R ²⁰¹～R²⁰⁶ and R ²²¹～R²²⁶, 2 groups bonded to the same nitrogen atom may be bonded to each other and form a 3-to 8-membered heterocyclic ring together with the nitrogen atom, and the hydrogen atom bonded to the ring may be substituted with an alkyl group having 1 to 12 carbon atoms.

R ²⁰⁷～R²¹⁸ and R ²²⁷～R²³⁸ are each independently a hydrogen atom, a halogen atom, an amino group which may be substituted, an amide group, a cyano group, a nitro group, a carboxyl group, or an alkyl group having 1 to 12 carbon atoms which may be substituted with a halogen atom or an alkoxy group having 1 to 12 carbon atoms which may be substituted with a halogen atom. In R ²⁰⁷～R²¹⁸ and R ²²⁷～R²³⁸, 2 groups adjacent to each other may be bonded to each other and form a 3-to 8-membered ring together with 2 carbon atoms of the phenyl group, and a hydrogen atom bonded to the ring may be substituted with an alkyl group having 1 to 12 carbon atoms.

In R ²⁰¹～R²⁰⁶ and R ²²¹～R²²⁶, examples of the substituent in the alkyl group having 1 to 20 carbon atoms which may be substituted or the alkoxy group having 1 to 20 carbon atoms which may be substituted, the aryl group having 6 to 14 carbon atoms which may be substituted, the aralkyl group having 7 to 14 carbon atoms which may be substituted, or the 3-to 14-membered heterocyclic group which may be substituted include: halogen atom, hydroxyl group, amino group which may be substituted with alkyl group having 1 to 6 carbon atoms, carboxyl group, sulfo group, cyano group, acyloxy group having 1 to 6 carbon atoms.

R ²⁰⁷～R²¹⁸ and R ²²⁷～R²³⁸ in the case where a ring is not formed are each independently preferably a hydrogen atom, a halogen atom, or an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms. The number of carbon atoms of the alkyl group or alkoxy group is preferably 1 to 6, more preferably 1 to 4.

In R ²⁰⁷～R²¹⁸ and R ²²⁷～R²³⁸, two groups adjacent to each other are bonded and a ring formed together with two carbon atoms of a phenyl group may be an alicyclic ring, an aromatic ring, or a heterocyclic ring. Examples of the hetero atom include a nitrogen atom, an oxygen atom and a sulfur atom.

In R ²⁰⁷～R²¹⁸ and R ²²⁷～R²³⁸, regarding the combination of bonding of two groups adjacent to each other, 2 groups exist on each of 3 phenyl groups bonded to the central nitrogen atom in the formulas (A1) and (A2), and 6 groups in total exist. Specifically, in the formula (A1), there are 6 groups of R ²⁰⁷ and R ²⁰⁸、R²⁰⁹ and R ²¹⁰、R²¹¹ and R ²¹²、R²¹³ and R ²¹⁴、R²¹⁵ and R ²¹⁶、R²¹⁷ and R ²¹⁸. Groups R ²²⁷ and R ²²⁸、R²²⁹ and R ²³⁰、R²³¹ and R ²³²、R²³³ and R ²³⁴、R²³⁵ and R ²³⁶、R²³⁷ and R ²³⁸ in formula (A2).

In R ²⁰⁷～R²¹⁸ of formula (A1) and R ²²⁷～R²³⁸ of formula (A2), the number of groups to which two adjacent groups are bonded may be 1 group, or may be 2 or more groups, or may be up to 6 groups all bonded. For 3 phenyl groups, 1 group is preferably bonded to each phenyl group, and 3 groups are bonded in total.

Examples of the divalent group obtained by bonding the two adjacent groups include, specifically, an alkylene group having 1 to 6 carbon atoms which may contain 1 to 2 nitrogen atoms as hetero atoms and may have an unsaturated bond between the atoms. More specifically, the following groups (X-1) to (X-4) are exemplified. The hydrogen atom of these divalent groups may be substituted with an alkyl group having 1 to 12 carbon atoms.

- (CH ₂)_n - (n is an integer of 1 to 6) … … (X-1)

-CH＝CH-CH＝CH-……(X-2)

-CH₂-CH＝CH-……(X-3)

-N＝CH-NH-……(X-4)

R ²⁰⁷～R²¹⁸ and R ²²⁷～R²³⁸ are each independently preferably a hydrogen atom, a halogen atom, or an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms, and preferably a hydrogen atom or an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms. The number of carbon atoms of the alkyl group or alkoxy group is preferably 1 to 6, more preferably 1 to 4.

In addition, R ²⁰¹ and R ²⁰⁷、R²⁰² and R ²¹⁰、R²⁰³ and R ²¹¹、R²⁰⁴ and R ²¹⁴、R²⁰⁵ and R ²¹⁵、R²⁰⁶ and R ²¹⁸、R²²¹ and R ²²⁷、R²²² and R ²³⁰、R²²³ and R ²³¹、R²²⁴ and R ²³⁴、R²²⁵ and R ²³⁵、R²²⁶ and R ²³⁸ may be bonded to each other and form a 4-to 8-membered heterocyclic ring together with the nitrogen atom bonded to the phenyl group and the 2 carbon atoms of the phenyl group, and the hydrogen atom bonded to the ring may be substituted with an alkyl group having 1 to 12 carbon atoms.

Xa ^- and Xb ^- each independently represent a monovalent anion.

In the above, the alkyl group may be a straight chain, branched chain, cyclic or a combination of these structures. In addition, the same applies to the alkyl groups and aralkyl groups in the case where the aryl group below has an alkyl group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom and a chlorine atom are preferable.

In the above, the aryl group means a group bonded through a carbon atom constituting an aromatic ring (wherein no hetero atom is contained) of an aromatic compound, for example, a benzene ring, a naphthalene ring, a biphenyl, or the like. Aryl groups include structures in which a hydrogen atom bonded to a ring constituent atom other than a carbon atom contributing to the bonding is substituted with an alkyl group, such as tolyl, xylyl, and the like.

In the above, aralkyl means a group in which an alkyl group is bonded to an aromatic ring (wherein no hetero atom is contained) and bonded through a carbon atom constituting the alkyl group. Aralkyl groups include structures in which a hydrogen atom bonded to a ring constituent atom other than the atom to which an alkyl group contributing to the bonding is substituted with an alkyl group.

In the above, the heterocyclic group means a group bonded through an atom constituting an alicyclic ring or an aromatic ring, the atom constituting the ring of which contains a carbon atom and an atom other than a carbon atom. The heterocyclic group includes a structure in which a hydrogen atom bonded to a ring constituent atom other than an atom contributing to the bonding is substituted with an alkyl group. Examples of the atoms other than carbon atoms included in the heterocycle include oxygen atoms, nitrogen atoms and sulfur atoms, and the number of the atoms is preferably 1 to 2.

Examples of Xa ^- and Xb ^- include Cl^-、Br^-、I^-、F^-、ClO₄ ^-、BF₄ ^-、PF₆ ^-、SbF₆ ^-、CF₃SO₃ ^-、CH₃C₆H₄SO₃ ^-、N(SO₂R_f)₂ ^-、C(SO₂R_f)₃ ^-, respectively.

Here, R _f is a fluoroalkyl group having 1 to 4 carbon atoms, preferably a fluoroalkyl group having 1 to 2 carbon atoms, and more preferably a fluoroalkyl group having 1 carbon atom. When the number of carbon atoms is within the above range, durability such as heat resistance and moisture resistance is good, and solubility in an organic solvent to be described later is good. Examples of such R _f include: -perfluoroalkyl groups such as CF ₃、-C₂F₅、-C₃F₇、-C₄F₉, -C ₂F₄H、-C₃F₆H、-C₂F₈ H, and the like.

From the viewpoint of moisture resistance, the fluoroalkyl group is preferably a perfluoroalkyl group, and more preferably a trifluoromethyl group.

As Xa ^- and Xb ^-, each independently is preferably I^-、BF₄ ^-、SbF₆ ^-、PF₆-、ClO₄ ^-、N(SO₂CF₃)₂ ^-、C(SO₂CF₃)₃ ^- or the like, and from the viewpoint of small difference in optical characteristics in a methylene chloride solution and optical characteristics in a resin, sbF ₆ ^-、PF₆ ^- and N (SO ₂CF₃)₂ ^-, particularly preferably SbF ₆ ^-、N(SO₂CF₃)₂ ^-, and from the viewpoint of light durability, BF ₄ ^-、PF₆ ^-、N(SO₂CF₃)₂ ^- is preferable.

The dye (A1) is classified into 3 dyes (A1 a) to (A1 c) represented by the following formulas (A1 a), (A1 b) and (A1 c), respectively, according to the structure of a group bonded to a nitrogen atom bonded to the 4-position of 3 phenyl groups bonded to the nitrogen atom in the center. The pigments (A2) are classified into 3 pigments (A2 a) to (A2 c) represented by the following formulas (A2 a), (A2 b) and (A2 c), respectively, based on the structure of the group bonded to the nitrogen atom bonded to the 4-position of the 3 phenyl groups bonded to the nitrogen atom in the center.

The dye (A1 a) and the dye (A2 a) are structures in which a nitrogen atom bonded to the 4-position of 3 phenyl groups (hereinafter referred to as a 4-position nitrogen atom) does not form a heterocycle.

The dye (A1 b) and the dye (A2 b) are bonded to each other in at least 1 group of 2 groups bonded to each of 3 nitrogen atoms at 4 positions to form a heterocyclic ring structure. 2 groups of 2 groups each bonded to 3 nitrogen atoms at 4-position may be bonded to each other, or all of 3 groups may be bonded to each other.

The dye (A1 c) and the dye (A2 c) are structures in which at least 1 of 2 groups bonded to nitrogen atoms at 3-4 positions is bonded to a group bonded to 3-or 5-position of a phenyl group to form a heterocycle. The dye (A1 c) and the dye (A2 c) may have 2 to 6 of the heterocyclic rings.

In the formula (A1 a) and the formula (A2 a), R ²⁰¹～R²⁰⁶ and R ²²¹～R²²⁶ are each independently a hydrogen atom, a halogen atom, a sulfo group, a hydroxyl group, a cyano group, a nitro group, a carboxyl group, a phosphoric acid group, an alkyl group having 1 to 20 carbon atoms which may have an oxygen atom between carbon atoms and may be substituted, or an alkoxy group having 1 to 20 carbon atoms which may have an oxygen atom between carbon atoms and may be substituted, or an aryl group having 6 to 14 carbon atoms which may be substituted, an aralkyl group having 7 to 14 carbon atoms which may be substituted, or a heterocyclic group having 3 to 14 members which may be substituted. Wherein, the group having a substituted or unsubstituted amino group bonded to the phenyl group is excluded. R ²⁰¹～R²⁰⁶ and R ²²¹～R²²⁶ are each independently preferably an alkyl group having 1 to 12 carbon atoms, more preferably an alkyl group having 1 to 8 carbon atoms. R ²⁰⁷～R²¹⁸ and R ²²⁷～R²³⁸ each independently may be the same as R ²⁰⁷～R²¹⁸ and R ²²⁷～R²³⁸ in the formula (A1) and the formula (A2).

In the formula (A1 b), Q ¹、Q² and Q ³ represent divalent groups in the case where R ²⁰¹ and R ²⁰²、R²⁰³ and R ²⁰⁴, and R ²⁰⁵ and R ²⁰⁶ in the formula (A1) are bonded respectively and form a 3-to 8-membered heterocyclic ring together with the nitrogen atom to which these groups are bonded. In the formula (A2 b), Q ¹¹、Q¹² and Q ¹³ represent divalent groups in the case where R ²²¹ and R ²²²、R²²³ and R ²²⁴, and R ²²⁵ and R ²²⁶ in the formula (A2) are bonded respectively and form a 3-to 8-membered heterocyclic ring together with the nitrogen atom to which these groups are bonded.

The formula (A1 b) may have at least one of Q ¹～Q³, two or more, or three, and the formula (A2 b) may have at least one of Q ¹¹～Q¹³, two or more, or three. The hydrogen atoms bonded to Q ¹～Q³ and Q ¹¹～Q¹³ may be independently substituted with an alkyl group having 1 to 12 carbon atoms.

Q ¹～Q³ and Q ¹¹～Q¹³ are each independently preferably an alkylene group represented by- (CH ₂)_n1 - (n 1 is an integer of 2 to 7), and a hydrogen atom of the alkylene group may be substituted with an alkyl group having 1 to 12 carbon atoms.

R ²⁰¹～R²⁰⁶ and R ²²¹～R²²⁶ in the case where a heterocycle is not formed may each independently be the same as R ²⁰¹～R²⁰⁶ and R ²²¹～R²²⁶ in the formula (A1 a) and the formula (A2 a). R ²⁰⁷～R²¹⁸ and R ²²⁷～R²³⁸ each independently may be the same as R ²⁰⁷～R²¹⁸ and R ²²⁷～R²³⁸ in the formula (A1) and the formula (A2).

In the formula (A1 c), Q ⁴～Q⁹ represents a divalent group in the case where R ²⁰¹ and R ²⁰⁷、R²⁰² and R ²¹⁰、R²⁰³ and R ²¹¹、R²⁰⁴ and R ²¹⁴、R²⁰⁵ and R ²¹⁵、R²⁰⁶ and R ²¹⁸ are bonded and form a 4-to 8-membered heterocyclic ring together with the nitrogen atom to which these groups are bonded and the carbon atom of the phenyl group, respectively. In the formula (A2 c), Q ¹⁴～Q¹⁹ represents a divalent group in the case where R ²²¹ and R ²²⁷、R²²² and R ²³⁰、R²²³ and R ²³¹、R²²⁴ and R ²³⁴、R²²⁵ and R ²³⁵、R²²⁶ and R ²³⁸ are bonded and form a 4-to 8-membered heterocyclic ring together with the nitrogen atom to which these groups are bonded and the carbon atom of the phenyl group, respectively.

The formula (A1 c) may have at least one of Q ⁴～Q⁹, may have two or more, or may have at most six, and the formula (A2 c) may have at least one of Q ¹⁴～Q¹⁹, may have two or more, or may have at most six. The hydrogen atoms bonded to Q ⁴～Q⁹ and Q ¹⁴～Q¹⁹ may be independently substituted with an alkyl group having 1 to 12 carbon atoms.

Q ⁴～Q⁹ and Q ¹⁴～Q¹⁹ are each independently preferably an alkylene group represented by- (CH ₂)_n2 - (n 2 is an integer of 1 to 5), and a hydrogen atom of the alkylene group may be substituted with an alkyl group having 1 to 12 carbon atoms.

R ²⁰¹～R²¹⁸ and R ²²¹～R²³⁸ in the case where a heterocycle is not formed may each independently be the same as R ²⁰¹～R²¹⁸ and R ²²¹～R²³⁸ in the formula (A1) and the formula (A2).

As the coloring matter (A1 a) and the coloring matter (A2 a), more specifically, compounds in table 1 and table 2 below are listed as R ²⁰¹～R²¹⁸ and R ²²¹～R²³⁸, respectively. In the exemplified pigment (A1 a), since the same groups are R ²⁰¹、R²⁰³ and R ²⁰⁵, R ²⁰¹、R²⁰³ and R ²⁰⁵ are collectively shown in table 1 in one column. R ²⁰²、R²⁰⁴ and R ²⁰⁶ are likewise indicated in summary. For R ²⁰⁷～R²¹⁸, the substituents at the same position in the 3 phenyl groups bonded to the central nitrogen atom are summarized and shown as "R²⁰⁷、R²¹¹、R²¹⁵"、"R²⁰⁸、R²¹²、R²¹⁶"、"R²⁰⁹、R²¹³、R²¹⁷"、"R²¹⁰、R²¹⁴、R²¹⁸". The same method as described above is also used for the pigment (A2 a).

In table 1, regarding the coloring matter (A1 a-21) and the coloring matter (A1 a-23), 3 groups of 2 groups R ²⁰⁷ and R ²⁰⁸、R²¹¹ and R ²¹², and R ²¹⁵ and R ²¹⁶, each of which is bonded, are described in a column formed by combining the columns "R ²⁰⁷、R²¹¹、R²¹⁵" and "R ²⁰⁸、R²¹²、R²¹⁶". For the pigment (A1 a-22), 3 groups of 2 groups R ²⁰⁹ and R ²¹⁰、R²¹³ and R ²¹⁴ adjacent to each other, and a divalent group formed by bonding R ²¹⁷ and R ²¹⁸ are described in a column formed by combining a column of "R ²⁰⁹、R²¹³、R²¹⁷" and a column of "R ²¹⁰、R²¹⁴、R²¹⁸". The same method as described for the pigments (A1 a-21), pigments (A1 a-22) and pigments (A1 a-23) in Table 2 was also used.

Although Xa ^- and Xb ^- are not shown in tables 1 and 2, among all the compounds, xa ^- or Xb ^- are each independently Cl^-、Br^-、I^-、F^-、ClO₄ ^-、BF₄ ^-、PF₆ ^-、SbF₆ ^-、CF₃SO₃ ^-、CH₃C₆H₄SO₃ ^-、N(SO₂R_f)₂ ^- or C (SO ₂R_f)₃ ^-.Xa^- or Xb ^- are each independently preferably I^-、BF₄ ^-、SbF₆ ^-、PF₆ ^-、ClO₄ ^-、N(SO₂CH₃)₂ ^- or C (SO ₂CH₃)₃ ^-).

The codes of the pigments corresponding to the above preferred monovalent anions are shown below. Among the pigments (A1 a-1), the case where Xa ^- is I ^- is referred to as pigment (A1 a-1I), the case where Xa ^- is BF ₄ ^- is referred to as pigment (A1 a-1B), The case where Xa ^- is SbF ₆ ^- is referred to as pigment (A1 a-1 Sb), the case where Xa ^- is PF ₆ ^- is referred to as pigment (A1 a-1P), The case where Xa ^- is ClO ₄ ^- is referred to as pigment (A1 a-1 Cl), the case where Xa ^- is N [ SO ₂CF₃]₂ ^- ] is referred to as pigment (A1 a-1 NS), Xa ^- is C (SO ₂CF₃)₃ ^-) and is represented as pigment (A1 a-1 CS). The same applies to the other pigments shown in tables 1 and 2. In tables 1 and 2, ph represents a phenyl group, and alkyl groups such as-C ₃H₇ are straight-chain alkyl groups.

More specifically, the pigment (A1 b) is a compound represented by Q ¹～Q³ and R ²⁰⁷～R²¹⁸ in table 3 below. In the exemplified pigment (A1 b), Q ¹、Q² and Q ³ are collectively shown in table 3 in one column, since they have the same groups as Q ¹、Q² and Q ³. The same description as in table 1 is used for R ²⁰⁷～R²¹⁸. More specifically, the pigment (A2 b) is a compound represented by Q ¹¹～Q¹³ and R ²²⁷～R²³⁸ in table 4 below. In the exemplified pigment (A2 b), Q ¹¹、Q¹² and Q ¹³ are shown in table 4 together in one column, since they have the same groups as Q ¹¹、Q¹² and Q ¹³. The same description as in table 2 is used for R ²²⁷～R²³⁸.

Although Xa ^- and Xb ^- are not shown in tables 3 and 4, xa ^- or Xb ^- are the same as the pigment (A1 a) shown in table 1 in all the compounds. In tables 3 and 4, the alkyl groups such as-C ₄H₉ are straight-chain alkyl groups.

TABLE 3 Table 3

TABLE 4 Table 4

More specifically, the pigment (A1 c) is a compound shown in table 5 below as Q⁴～Q⁹、"R²⁰²、R²⁰⁴、R²⁰⁶"、"R²⁰⁸、R²¹²、R²¹⁶"、"R²⁰⁹、R²¹³、R²¹⁷"、"R²¹⁰、R²¹⁴、R²¹⁸". In the exemplified pigment (A1 c), Q ⁴、Q⁶ and Q ⁸ are shown in table 5 together in one column, since they have the same groups as Q ⁴、Q⁶ and Q ⁸. In addition, in the case of Q ⁵、Q⁷ and Q ⁹, Q ⁵、Q⁷ and Q ⁹ are collectively shown in table 5 in one column since they have the same group as Q ⁵、Q⁷ and Q ⁹. "R ²⁰²、R²⁰⁴、R²⁰⁶" and "R ²¹⁰、R²¹⁴、R²¹⁸" are the groups which are present in the case of pigments (A1 c) without Q ⁵、Q⁷ and Q ⁹.

More specifically, the pigment (A2 c) is a compound shown in table 6 below as Q¹⁴～Q¹⁹、"R²²²、R²²⁴、R²²⁶"、"R²²⁸、R²³²、R²³⁶"、"R²²⁹、R²³³、R²³⁷"、"R²³⁰、R²³⁴、R²³⁸". In the exemplified pigment (A2 c), Q ¹⁴、Q¹⁶ and Q ¹⁸ are shown in table 6 together in one column, since they have the same groups as Q ¹⁴、Q¹⁶ and Q ¹⁸. In addition, in the case of Q ¹⁵、Q¹⁷ and Q ¹⁹, Q ¹⁵、Q¹⁷ and Q ¹⁹ are collectively shown in table 6 in one column since they have the same group as Q ¹⁵、Q¹⁷ and Q ¹⁹. "R ²²²、R²²⁴、R²²⁶" and "R ²³⁰、R²³⁴、R²³⁸" are the groups which are present in the case of pigments (A2 c) without Q ¹⁵、Q¹⁷ and Q ¹⁹.

The same description as in table 1 is used for "R²⁰²、R²⁰⁴、R²⁰⁶"、"R²⁰⁸、R²¹²、R²¹⁶"、"R²⁰⁹、R²¹³、R²¹⁷"、"R²¹⁰、R²¹⁴、R²¹⁸",. The same description as in table 2 is used for "R²²²、R²²⁴、R²²⁶"、"R²²⁸、R²³²、R²³⁶"、"R²²⁹、R²³³、R²³⁷"、"R²³⁰、R²³⁴、R²³⁸",.

Among the coloring matter (A1C) and the coloring matter (A2C), compounds that are bilaterally symmetrical, for example, those in which the coloring matter (A1C-1) and "Q ⁵、Q⁷、Q⁹" are-CH ₂-CH₂-CH₂-CH₂-、"R²⁰¹、R²⁰³、R²⁰⁵ "are-C ₂H₅ and "R²⁰⁷、R²¹¹、R²¹⁵"、"R²⁰⁸、R²¹²、R²¹⁶"、"R²⁰⁹、R²¹³、R²¹⁷" is H, are regarded as the same compounds.

Although Xa ^- and Xb ^- are not shown in tables 5 and 6, xa ^- or Xb ^- are the same as the pigment (A1 a) shown in table 1 in all the compounds. In tables 5 and 6, the alkyl groups such as-C ₃H₇ are straight-chain alkyl groups. In tables 5 and 6, the divalent group shown in columns "Q⁴、Q⁶、Q⁸"、"Q⁵、Q⁷、Q⁹"、"Q¹⁴、Q¹⁶、Q¹⁸" and "Q ¹⁵、Q¹⁷、Q¹⁹" is in a form in which the left side is bonded to a nitrogen atom and the right side is bonded to a carbon atom of a phenyl group.

Among these pigments (A1), pigments (A1 a-5 Sb), pigments (A1 a-5 NS), pigments (A1 a-5P), pigments (A1 a-5 Cl), pigments (A1 a-5B), pigments (A1 a-1 NS), pigments (A1 a-4 Sb), pigments (A1 a-4 NS), pigments (A1 a-4P), pigments (A1 a-7 NS), pigments (A1 a-7P) and the like are preferable, and pigments (A1 a-5 Sb), pigments (A1 a-5 NS), pigments (A1 a-5P), pigments (A1 a-4 Sb), pigments (A1 a-4 NS) and pigments (A1 a-4P) are more preferable.

As the coloring matter (A1 b), coloring matter (A1 b-1 Sb), coloring matter (A1 b-1 NS), coloring matter (A1 b-1P) and the like are preferable. As the dye (A1 c), the dye (A1 c-3 NS), the dye (A1 c-3P), the dye (A1 c-4 NS), the dye (A1 c-4P), the dye (A1 c-10 NS), the dye (A1 c-10P) and the like are preferable, and the dye (A1 b-1 NS), the dye (A1 c-4P), the dye (A1 c-10 NS) and the dye (A1 c-10P) are more preferable.

Among them, the pigment (A2) is preferably pigment (A2 a-5 Sb), pigment (A2 a-5 NS), pigment (A2 a-5P), pigment (A2 a-5 Cl), pigment (A2 a-5B), pigment (A2 a-1 NS), pigment (A2 a-4 Sb), pigment (A2 a-4 NS), pigment (A2 a-4P), pigment (A2 a-7 NS), pigment (A2 a-7P) or the like, more preferably pigment (A2 a-5 Sb), pigment (A2 a-5 NS), pigment (A2 a-5P), pigment (A2 a-4 Sb), pigment (A2 a-4 NS) or pigment (A2 a-4P).

As the coloring matter (A2 b), coloring matter (A2 b-1 Sb), coloring matter (A2 b-1 NS), coloring matter (A2 b-1P) and the like are preferable. As the dye (A2 c), the dye (A2 c-3 NS), the dye (A2 c-3P), the dye (A2 c-4 NS), the dye (A2 c-4P), the dye (A2 c-10 NS), the dye (A2 c-10P) and the like are preferable, and the dye (A2 b-1 NS), the dye (A2 c-4P), the dye (A2 c-10 NS) and the dye (A2 c-10P) are more preferable.

The NIR dye (a) may be composed of one compound or two or more compounds. In the case of a composition comprising two or more compounds, it is not necessarily required that each compound has the property of the NIR dye (a), as long as the mixture has the property of the NIR dye (a).

The pigment (A1) and the pigment (A2) can be produced by a known method. The pigments (A1 a) to (A1 c) can be produced by the method described in JP-A2007-197492, for example. The pigments (A2 a) to (A2 c) can be produced by the method described in, for example, japanese patent application laid-open No. 2009-221146.

NIR pigment (B)

The NIR dye (B) is a dye having a maximum absorption wavelength lambda _max(B)TR in a wavelength range of 1100nm to 1200nm in a spectral transmittance curve of 350nm to 1200nm measured by including the dye in the transparent resin (P). The maximum absorption wavelength lambda _max(B)TR is preferably in the wavelength range from 1100nm to 1150 nm.

The NIR pigment (B) preferably also has high visible light transmittance properties in the resin.

As the NIR dye (B), the molecular structure is not particularly limited as long as the maximum absorption wavelength lambda _max(B)TR is in the range of 1100nm to 1200 nm. Specifically, it is possible to list: is selected from the group consisting of cyanine pigments, croconic acid pigments, phthalocyanine pigments, squaraineAt least one pigment selected from the group consisting of a salt pigment, a diimmonium pigment, a diketopyrrolopyrrole pigment, a metal complex pigment and a metal oxide is particularly preferably a diimmonium pigment from the viewpoint of high visible light transmittance.

Specifically, the diimmonium dye used as the NIR dye (B) is preferably one or more selected from the group consisting of a compound represented by the following formula (B1) and a compound represented by the following formula (B2).

Symbols in the formulae (B1) and (B2) are as follows.

R ²⁴¹～R²⁴⁸ and R ²⁶¹～R²⁶⁸ are each independently a hydrogen atom, a halogen atom, a sulfo group, a hydroxyl group, a cyano group, a nitro group, a carboxyl group, a phosphoric acid group, an alkyl group having 1 to 20 carbon atoms which may have an unsaturated bond or an oxygen atom between carbon atoms and may be substituted, or an alkoxy group having 1 to 20 carbon atoms which may have an unsaturated bond or an oxygen atom between carbon atoms and may be substituted, or an aryl group having 6 to 14 carbon atoms which may be substituted, an aralkyl group having 7 to 14 carbon atoms which may be substituted, or a heterocyclic group having 3 to 14 members which may be substituted. In R ²⁴¹～R²⁴⁸ and R ²⁶¹～R²⁶⁸, 2 groups bonded to the same nitrogen atom may be bonded to each other and form a 3-to 8-membered heterocyclic ring together with the nitrogen atom, and the hydrogen atom bonded to the ring may be substituted with an alkyl group having 1 to 12 carbon atoms.

In R ²⁴¹～R²⁴⁸ and R ²⁶¹～R²⁶⁸, examples of the substituent in the alkyl group having 1 to 20 carbon atoms which may be substituted or the alkoxy group having 1 to 20 carbon atoms which may be substituted, the aryl group having 6 to 14 carbon atoms which may be substituted, the aralkyl group having 7 to 14 carbon atoms which may be substituted, or the 3-to 14-membered heterocyclic group which may be substituted include: halogen atom, hydroxyl group, amino group which may be substituted with alkyl group having 1 to 6 carbon atoms, carboxyl group, sulfo group, cyano group, acyloxy group having 1 to 6 carbon atoms.

R ²⁴¹～R²⁴⁸ and R ²⁶¹～R²⁶⁸ in the case where a ring is not formed are each independently preferably an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms. The number of carbon atoms of the alkyl group or alkoxy group is preferably 1 to 8.

As R ²⁴¹～R²⁴⁸ and R ²⁶¹～R²⁶⁸, a straight-chain alkyl group or a branched alkyl group having 4 to 6 carbon atoms is preferable from the following viewpoints. The solubility in an organic solvent is improved by having 4 or more carbon atoms, and the heat resistance is improved by having 6 or less carbon atoms. The reason for the improvement in heat resistance is thought to be an increase in the melting point of the pigment.

As the divalent group in the case where two groups bonded to the same nitrogen atom are bonded to each other, that is, the divalent group in the case where R ²⁴¹ and R ²⁴²、R²⁴³ and R ²⁴⁴、R²⁴⁵ and R ²⁴⁶、R²⁴⁷ and R ²⁴⁸ are each bonded, an alkylene group represented by- (CH ₂)_n3 - (n 3 is an integer of 2 to 7) is preferable, and a hydrogen atom of the alkylene group may be substituted with an alkyl group having 1 to 12 carbon atoms.

R ²⁴⁹～R²⁵³ and R ²⁶⁹～R²⁷³ are each independently a hydrogen atom, a halogen atom, an amino group which may be substituted, an amide group, a cyano group, a nitro group, a carboxyl group, or an alkyl group having 1 to 12 carbon atoms which may be substituted with a halogen atom or an alkoxy group having 1 to 12 carbon atoms which may be substituted with a halogen atom. Four of each of R ²⁴⁹～R²⁵³ may be the same or different, and four of each of R ²⁶⁹～R²⁷³ may be the same or different.

R ²⁴⁹～R²⁵³ and R ²⁶⁹～R²⁷³ are each independently preferably a hydrogen atom, a halogen atom, or an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms. The number of carbon atoms of the alkyl group or alkoxy group is preferably 1 to 6, more preferably 1 to 4.

Xc ^- and Xd ^- each independently represent a monovalent anion. Examples of Xc ^- and Xd ^- include ：Cl^-、Br^-、I^-、F^-、ClO₄ ^-、BF₄ ^-、PF₆ ^-、SbF₆ ^-、CF₃SO₃ ^-、CH₃C₆H₄SO₃ ^-、N(SO₂R_f)₂ ^-、C(SO₂R_f)₃ ^-. Among them, PF₆ ^-、N(SO₂R_f)₂ ^-、C(SO₂R_f)₃ ^-, is preferable and PF ₆ ^-、N(SO₂R_f)₂ ^- is more preferable.

Here, R _f may be the same as in the case of Xa ^- and Xb ^- described above, and the preferable mode is also the same.

More specifically, the coloring matter (B1) and the coloring matter (B2) are compounds shown in tables 7 and 8 below as R ²⁴¹～R²⁵³ and R ²⁶¹～R²⁷³, respectively. In the exemplified pigment (B1), since the same groups are R ²⁴¹、R²⁴³、R²⁴⁵ and R ²⁴⁷, R ²⁴¹、R²⁴³、R²⁴⁵ and R ²⁴⁷ are collectively shown in table 7 in one column. R ²⁴²、R²⁴⁴、R²⁴⁶ and R ²⁴⁸ are likewise indicated in summary. R ²⁴⁹ ₄～R²⁵³ ₄ represents that R ²⁴⁹～R²⁵³ each has 4 groups or atoms, and in the case where the 4 groups or atoms are the same, only one of the groups or atoms is described. When 4 groups or atoms are different, 4 atoms or groups are described as "H, H, H, -CH ₃". The location of the atom or group bond is not specified. For example, "H, H, H, -CH ₃" means that-CH ₃ is bonded to any one of 4 carbon atoms other than the carbon atom to which the nitrogen atom of the benzene ring is bonded.

In Table 7, the pigment (B1-6) represents a case where R ²⁴¹ and R ²⁴²、R²⁴³ and R ²⁴⁴、R²⁴⁵ and R ²⁴⁶、R²⁴⁷ and R ²⁴⁸ are each bonded and are each-CH ₂-CH₂-CH₂-CH₂ -. The method described for the pigment (B1) in table 7 was also applied to the pigment (B2) in table 8.

Although Xc ^- and Xd ^- are not shown in tables 7 and 8, among all the compounds, xc ^- or Xd ^- are each independently Cl^-、Br^-、I^-、F^-、ClO₄ ^-、BF₄ ^-、PF₆ ^-、SbF₆ ^-、CF₃SO₃ ^-、CH₃C₆H₄SO₃ ^-、N(SO₂R_f)₂ ^- or C (SO ₂R_f)₃ ^-.Xc^- and Xd ^- are each independently preferably I^-、BF₄ ^-、SbF₆ ^-、PF₆ ^-、ClO₄ ^-、N(SO₂CF₃)₂ ^- or C (SO ₂CF₃)₃ ^-).

The codes of the pigments corresponding to the above preferred monovalent anions are shown below. for example, in the case where Xc ^- is I ^- in the pigment (B1-1), the case where Xc ^- is BF ₄ ^- is represented as pigment (B1-1B), the case where Xc ^- is SbF ₆ ^- is denoted as pigment (B1-1 Sb), the case where Xc ^- is PF ₆ ^- is denoted as pigment (B1-1P), The case where Xc ^- is ClO ₄ ^- is referred to as pigment (B1-1 Cl), the case where Xc ^- is N [ SO ₂CF₃]₂ ^- ] is referred to as pigment (B1-1 NS), Xc ^- is C (SO ₂CF₃)₃ ^-) and is represented as a dye (B1-1 CS). The same applies to the other pigments shown in tables 7 and 8. In tables 7 and 8, ph represents a phenyl group, and the alkyl group such as-C ₃H₇ is a straight-chain alkyl group.

Among these pigments (B1), pigments (B1-5 NS), pigments (B1-5 Sb), pigments (B1-5P), pigments (B1-4 NS), pigments (B1-4 Sb), pigments (B1-4P) and the like are preferable. Among these pigments (B2), pigments (B2-4 NS), pigments (B2-4P), pigments (B2-5 NS), pigments (B2-5P) and the like are preferable.

The NIR dye (B) may be composed of one compound or two or more compounds. In the case of a composition comprising two or more compounds, it is not necessarily required that each compound has the property of the NIR dye (B), as long as the mixture has the property of the NIR dye (B).

The pigment (B1) and the pigment (B2) can be produced by a known method. The pigment (B1) can be produced by a method described in, for example, japanese patent application laid-open No. 2009-137894. The pigment (B2) can be produced by the method described in JP-A-2000-229931, for example.

Examples of commercial products of the pigment (B1) include: CIR-1081, CIR-1083, CIR-1085, CIR-RL (trade name in the above) and the like manufactured by Kayasorb IRG-022、Kayasorb IRG-023、Kayasorb IRG-024、Kayasorb IRG-068、Kayasorb IRG-069、Kayasorb IRG-079; Japanese Carlit Co., ltd.

NIR pigment (C)

The NIR dye (C) is a squaraine dye having a maximum absorption wavelength lambda _max(C)TR in a wavelength range of 630nm to 750nm in a spectral transmittance curve of 350nm to 1200nm measured by inclusion in the transparent resin (P). The maximum absorption wavelength lambda _max(C)TR is preferably in the wavelength range of 650nm to 740 nm.

The NIR dye (C) is further preferably high in visible light transmittance in the resin, and shows a sharp increase when the transmittance increases from the maximum absorption wavelength λ _max(C)TR to the short wavelength side.

The NIR dye (C) is in squaric acid satisfying the requirement of maximum absorption wavelength lambda _max(C)TR The salt pigment is not particularly limited in addition thereto. As the NIR dye (C), more specifically, it is preferable that in the squaric acid represented by the following formula (I) or formula (II)A salt pigment.

Wherein the symbols in formula (I) are as follows.

R ²⁴ and R ²⁶ each independently represents a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group having 1 to 20 carbon atoms or an alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 1 to 10 carbon atoms, an aryl group having 6 to 11 carbon atoms, an aralkyl group having 7 to 18 carbon atoms which may have a substituent and may have an oxygen atom between carbon atoms, -NR ²⁷R²⁸(R²⁷ and R ²⁸ each independently represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, -C (=O) -R ²⁹(R²⁹ is a hydrogen atom, a halogen atom, a hydroxyl group, a hydrocarbon group having 1 to 25 carbon atoms which may have a substituent and may have an unsaturated bond, an oxygen atom, a saturated or unsaturated ring structure between carbon atoms, -NHR ³⁰ or-SO ₂-R³⁰(R³⁰ each is a hydrogen atom which may be substituted with a halogen atom, a hydroxyl group, a carboxyl group, a sulfo group or a cyano group and may have an unsaturated bond between carbon atoms, an oxygen atom, a hydrocarbon group having 1 to 25 carbon atoms of a saturated or unsaturated ring structure, or an alkoxy group having ⁴¹、R⁴² of the following formula (R) is independently represents a hydrogen atom, a halogen atom, a hydrogen atom or an alkyl group having 5310 carbon atoms; k is 2 or 3).

R ²¹ and R ²²、R²² and R ²⁵, and R ²¹ and R ²³ may be linked to each other and form, together with the nitrogen atom, a five-or six-membered heterocyclic ring a, a heterocyclic ring B and a heterocyclic ring C, respectively.

R ²¹ and R ²² in the case of forming a heterocyclic ring A are divalent groups-Q-to which R ²¹ and R ²² are bonded, and represent an alkylene group in which a hydrogen atom may be substituted with an alkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 10 carbon atoms or an acyloxy group having 1 to 10 carbon atoms which may have a substituent, or an alkylene group in which a hydrogen atom may be substituted with an alkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 10 carbon atoms or an acyloxy group having 1 to 10 carbon atoms which may have a substituent.

For R ²² and R ²⁵ in the case of the formation of heterocycle B and R ²¹ and R ²³ in the case of the formation of heterocycle C, As the divalent group-X ¹-Y¹ -to which R ²² and R ²⁵ are bonded and the divalent group-X ²-Y² -to which R ²¹ and R ²³ are bonded (the side to which nitrogen is bonded is X ¹ and X ²),X¹ and X ² are each a group represented by the following formula (1X) or (2X), y ¹ and Y ² are each a group represented by any one selected from the following formulas (1Y) to (5Y). In the case where each of X ¹ and X ² is a group represented by the following formula (2X), each of Y ¹ and Y ² may be a single bond, in this case, an oxygen atom may be present between carbon atoms.

In the formula (1 x), 4Z's each independently represent a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 6 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms, or-NR ³⁸R³⁹(R³⁸ and R ³⁹ each independently represent a hydrogen atom or an alkyl group having 1 to 20 carbon atoms. R ³¹～R³⁶ is independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 10 carbon atoms, and R ³⁷ is an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 10 carbon atoms.

One of R ²⁷、R²⁸、R²⁹、R³¹～R³⁷, R ²¹～R²³ and R ²⁵ in the case where a heterocyclic ring is not formed, may be bonded to each other with any of them to form a five-membered ring or a six-membered ring. R ³¹ and R ³⁶、R³¹ and R ³⁷ may be directly bonded.

R ²¹、R²²、R²³ and R ²⁵ in the case where a heterocyclic ring is not formed each independently represent a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 1 to 10 carbon atoms, an aryl group having 6 to 11 carbon atoms, or an aralkyl group having 7 to 18 carbon atoms which may have a substituent and may have an oxygen atom between carbon atoms.

In the formula (I), unless otherwise specified, the hydrocarbon group is an alkyl group, an aryl group or an aralkyl group. Unless otherwise specified, the alkyl moiety in the alkyl group as well as the alkoxy, aryl or aralkyl group may be straight-chain, branched, cyclic, or a combination of these structures.

The same applies to alkyl, alkoxy, aryl, and aralkyl groups in other formulae. In formula (I), as substituents in R ²⁹, there may be mentioned: halogen atom, hydroxyl group, carboxyl group, sulfo group, cyano group, and acyloxy group having 1 to 6 carbon atoms. In addition to R ²⁹, as a substituent in the case of "may have a substituent", a halogen atom or an alkoxy group having 1 to 15 carbon atoms may be exemplified. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom and a chlorine atom are preferable.

Wherein the symbols in formula (II) are as follows.

The rings Z are each independently a five-membered ring or a six-membered ring having 0 to3 hetero atoms in the ring, and the hydrogen atoms that the rings Z have may be substituted. When a hydrogen atom is substituted, examples of the substituent include: halogen atom or alkyl group having 1 to 10 carbon atoms which may have a substituent.

R ¹ and R ²、R² and R ³, and R ¹ and the carbon atom or heteroatom constituting the ring Z may be linked to each other and form, together with the nitrogen atom, a heterocycle A1, a heterocycle B1 and a heterocycle C1, respectively, in which case the hydrogen atoms possessed by the heterocycle A1, the heterocycle B1 and the heterocycle C1 may be substituted. When a hydrogen atom is substituted, examples of the substituent include: halogen atom or alkyl group having 1 to 15 carbon atoms which may have a substituent.

R ¹ and R ² in the case where a heterocyclic ring is not formed each independently represent a hydrogen atom, a halogen atom, or a hydrocarbon group which may contain an unsaturated bond, a heteroatom, a saturated or unsaturated ring structure between carbon atoms and may have a substituent. R ⁴ and R ³ in the case where a heterocyclic ring is not formed each independently represent a hydrogen atom, a halogen atom, or an alkyl group which may contain a heteroatom and may have a substituent between carbon atoms or an alkoxy group which may contain a heteroatom and may have a substituent between carbon atoms.

In the formula (II), the number of carbon atoms of the hydrocarbon group may be 1 to 15. The number of carbon atoms of the alkyl group or the alkoxy group may be 1 to 10. In the formula (II), as the substituent in the case of "may have a substituent", a halogen atom or an alkoxy group having 1 to 10 carbon atoms may be exemplified. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom and a chlorine atom are preferable.

Examples of the compound (I) include compounds represented by any of the formulas (I-1) to (I-4).

Wherein the symbols in the formulae (I-1) to (I-4) are the same as the respective definitions of the same symbols in the formula (I), and the preferable mode is the same.

Among the compounds (I-1) to (I-4), the compound (I-1) to (I-3) is preferable, and the compound (I-1) is particularly preferable, from the viewpoint of improving the visible light transmittance of the resin layer containing the pigment as the NIR pigment (C).

In the compound (I-1), as X ¹, the group (2X) is preferable, and as Y ¹, a single bond or the group (1Y) is preferable. In this case, R ³¹～R³⁶ is preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and more preferably a hydrogen atom or a methyl group. Specifically, examples of-Y ¹-X¹ -include divalent organic groups represented by the formulas (11-1) to (12-3).

-C(CH₃)₂-CH(CH₃)-……(11-1)

-C(CH₃)₂-CH₂-……(11-2)

-C(CH₃)₂-CH(C₂H₅)-……(11-3)

-C(CH₃)₂-C(CH₃)(nC₃H₇)-……(11-4)

-C(CH₃)₂-CH₂-CH₂-……(12-1)

-C(CH₃)₂-CH₂-CH(CH₃)-……(12-2)

-C(CH₃)₂-CH(CH₃)-CH₂-……(12-3)

In addition, in the compound (I-1), R ²¹ is independently more preferably a group represented by the formula (4-1) or the formula (4-2) from the viewpoints of solubility, heat resistance and steepness of a change in the spectral transmittance curve in the vicinity of a boundary between the visible light region and the near infrared region.

In the formula (4-1) and the formula (4-2), R ⁸¹～R⁸⁵ independently represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms.

In the compound (I-1), R ²⁴ is preferably-NR ²⁷R²⁸. as-NR ²⁷R²⁸, from the viewpoint of solubility in a resin combined with the NIR dye (C) and a solvent used when forming a resin layer on a substrate, it is preferably-NH-C (=o) -R ²⁹. The formula (I-11) shows a compound in which R ²⁴ is-NH-C (=O) -R ²⁹ in the compound (I-1).

R ²³ and R ²⁶ in the compound (I-11) are each independently preferably a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms or an alkoxy group having 1 to 6 carbon atoms, more preferably each a hydrogen atom.

In the compound (I-11), R ²⁹ is preferably an alkyl group having 1 to 20 carbon atoms which may have a substituent, an aryl group having 6 to 10 carbon atoms which may have a substituent, or an aralkyl group having 7 to 18 carbon atoms which may have a substituent and may have an oxygen atom between carbon atoms. As the substituent, there may be mentioned: halogen atoms such as fluorine atoms, hydroxyl groups, carboxyl groups, sulfo groups, cyano groups, alkyl groups having 1 to 6 carbon atoms, fluoroalkyl groups having 1 to 6 carbon atoms, alkoxy groups having 1 to 6 carbon atoms, acyloxy groups having 1 to 6 carbon atoms, and the like.

R ²⁹ is preferably a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 1 to 10 carbon atoms, an aryl group having 6 to 11 carbon atoms, or an aralkyl group having 7 to 18 carbon atoms which may have a substituent and may have an oxygen atom between carbon atoms.

As R ²⁹, preferred is a group selected from: straight-chain, branched, and cyclic alkyl groups having 1 to 17 carbon atoms which may be substituted with fluorine atoms, phenyl groups which may be substituted with fluoroalkyl groups having 1 to 6 carbon atoms and/or alkoxy groups having 1 to 6 carbon atoms, and aralkyl groups which may have 7 to 18 carbon atoms having an oxygen atom between carbon atoms and have, at the end, phenyl groups which may be substituted with alkyl groups having 1 to 6 carbon atoms and/or alkoxy groups having 1 to 6 carbon atoms.

As R ²⁹, the following groups may be used independently and preferably: more than one hydrogen atom may be substituted with a halogen atom, a hydroxyl group, a carboxyl group, a sulfo group or a cyano group, and a hydrocarbon group having 5 to 25 carbon atoms which may have an unsaturated bond, an oxygen atom, a saturated or unsaturated ring structure between carbon atoms, and at least one branched chain may be contained. Examples of such R ²⁹ include groups represented by the following formulas (11 a), (11 b), (12 a) to (12 e) and (13 a) to (13 e).

As the compound (I-11), more specifically, compounds shown in Table 9 below are listed. In Table 9, the group (11-1) is represented as (11-1). The same applies to other groups. In the other tables below, the radicals are likewise indicated. In addition, all compounds shown in Table 9 are in squaraineThe meanings of the symbols on the left and right of the salt skeleton are the same. In squaraines shown in other tables belowThe same applies to the salt pigment.

TABLE 9

In the compound (I-1), R ²⁴ is preferably-NH-SO ₂-R³⁰ from the viewpoint of improving the transmittance of visible light, particularly the transmittance of light having a wavelength of 430nm to 550 nm. The formula (I-12) shows a compound in which R ²⁴ is-NH-SO ₂-R³⁰ in the compound (I-1).

R ²³ and R ²⁶ in the compound (I-12) are each independently preferably a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms or an alkoxy group having 1 to 6 carbon atoms, more preferably each a hydrogen atom.

In the compound (I-12), R ³⁰ is independently preferably an alkyl group having 1 to 12 carbon atoms which may have a branched chain, an alkoxy group having 1 to 12 carbon atoms which may have a branched chain, or a hydrocarbon group having 6 to 16 carbon atoms which has an unsaturated ring structure, from the viewpoint of light resistance. As the unsaturated ring structure, there may be mentioned: benzene, toluene, xylene, furan, benzofuran, and the like. R ³⁰ is independently more preferably an alkyl group having 1 to 12 carbon atoms which may have a branch or an alkoxy group having 1 to 12 carbon atoms which may have a branch. In each group representing R ³⁰, a part or all of hydrogen atoms may be substituted with halogen atoms, particularly fluorine atoms. The degree of substitution of the hydrogen atom with the fluorine atom is such that the adhesion of the resin layer containing the dye (I-12) to, for example, a transparent substrate is not lowered.

Specific examples of R ³⁰ having an unsaturated ring structure include groups represented by the following formulas (P2), (P3), (P7), (P8), (P10) and (P13).

As the compound (I-12), more specifically, compounds shown in Table 10 below are exemplified.

Table 10

Examples of the compound (II) include compounds represented by any of the formulas (II-1) to (II-3).

Wherein in the formula (II-1) and the formula (II-2), R ¹ and R ² each independently represent a hydrogen atom, a halogen atom, or an alkyl group having 1 to 15 carbon atoms which may have a substituent, and R ³～R⁶ each independently represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 10 carbon atoms which may have a substituent.

Wherein in the formula (II-3), R ¹、R⁴ and R ⁹～R¹² each independently represent a hydrogen atom, a halogen atom, or an alkyl group having 1 to 15 carbon atoms which may have a substituent, and R ⁷ and R ⁸ each independently represent a hydrogen atom, a halogen atom, or an alkyl group having 1 to 5 carbon atoms which may have a substituent.

From the viewpoints of solubility in resins, visible light transmittance, and the like, R ¹ and R ² in the compound (II-1) and the compound (II-2) are independently preferably an alkyl group having 1 to 15 carbon atoms, more preferably an alkyl group having 7 to 15 carbon atoms, still more preferably at least one of R ¹ and R ² is an alkyl group having 7 to 15 carbon atoms, particularly preferably both R ¹ and R ² are alkyl groups having 8 to 15 carbon atoms.

R ³ is independently preferably a hydrogen atom, a halogen atom or an alkyl group having 1 to 3 carbon atoms, more preferably a hydrogen atom, a halogen atom or a methyl group, from the viewpoints of solubility in a resin, visible light transmittance and the like. From the viewpoint of the steepness of the change in the vicinity of the boundary between the visible light region and the near infrared region, R ⁴ is preferably a hydrogen atom or a halogen atom, and particularly preferably a hydrogen atom. R ⁵ in the compound (II-1) and R ⁶ in the compound (II-2) are independently preferably a hydrogen atom, a halogen atom, or an alkyl group having 1 to 5 carbon atoms which may be substituted with a halogen atom, more preferably a hydrogen atom, a halogen atom or a methyl group.

The compound (II-1) is more specifically a compound shown in Table 11 below, and the compound (II-2) is more specifically a compound shown in Table 12 below. In tables 11 and 12, -C ₈H₁₇、-C₄H₉、-C₆H₁₃ represents a straight-chain octyl group, a straight-chain butyl group, a straight-chain hexyl group, respectively.

TABLE 11

Table 12

R ¹ in the compound (II-3) is independently preferably an alkyl group having 1 to 15 carbon atoms, more preferably an alkyl group having 1 to 10 carbon atoms, particularly preferably an ethyl group or an isopropyl group, from the viewpoints of solubility in a resin, visible light transmittance and the like.

From the viewpoints of visible light transmittance and ease of synthesis, R ⁴ is preferably a hydrogen atom or a halogen atom, and particularly preferably a hydrogen atom. R ⁷ and R ⁸ are independently preferably a hydrogen atom, a halogen atom, or an alkyl group having 1 to 5 carbon atoms which may be substituted with a halogen atom, more preferably a hydrogen atom, a halogen atom or a methyl group.

R ⁹～R¹² is independently preferably a hydrogen atom, a halogen atom, or an alkyl group having 1 to 5 carbon atoms which may be substituted with a halogen atom. As the-CR ⁹R¹⁰-CR¹¹R¹² -there may be mentioned the above-mentioned groups (11-1) to (11-3) or a divalent organic group represented by the following formula (11-5).

-C(CH₃)(CH₂-CH(CH₃)₂)-CH(CH₃)-……(11-5)

As the compound (II-3), more specifically, compounds shown in Table 13 below can be cited.

TABLE 13

As the NIR pigment (C), among them, pigment (I-11) and pigment (I-12) are preferable from the viewpoints of solubility in a resin or a solvent, and visible light transmittance, and pigment (I-11) shown in Table 9 and pigment (I-12) shown in Table 10 are more preferable. Among them, pigment (I-11-7), pigment (I-12-2), pigment (I-12-9), pigment (I-12-15), pigment (I-12-23), pigment (I-12-24) and the like are preferable.

The NIR dye (C) may be composed of one compound or two or more compounds. In the case of a composition comprising two or more compounds, it is not necessarily required that each compound has the property of the NIR dye (C), as long as the mixture has the property of the NIR dye (C).

Each of the compound (I) and the compound (II) can be produced by a known method. For example, the compound (I-11) can be produced by the method described in U.S. Pat. No. 5543086. The compound (I-12) can be produced, for example, by the method described in U.S. patent application publication No. 2014/0061505 and International publication No. 2014/088063. The compound (II) can be produced by the method described in the specification of International publication No. 2017/135359.

The UV dye optionally contained in the absorbing layer may be: Azoles, merocyanines, cyanines, naphthalimides, and the like, Diazoles (diazoles),Oxazines(s),Specific examples of the coloring matters include oxazolidines, naphthalenedicarboxylic acids, styryl groups, anthracene groups, cyclic carbonyl groups, and triazoles. Among them, preferred isAzole pigments or merocyanine pigments. In addition, one UV dye may be used alone or two or more UV dyes may be used in combination in the absorbing layer.

[ Transparent resin (P) ]

The transparent resin (P) has a Tg of 130 ℃ or higher and satisfies the above-mentioned requirements (1-1) to (1-6) in relation to the NIR dye (A). The transparent resin (P) preferably further satisfies one or more selected from the above-mentioned items (1-7) to (1-9) in terms of the relation with the NIR dye (A).

Tg was determined by DSC measurement (differential scanning calorimetry). If the Tg of the transparent resin (P) is 130 ℃ or higher, the absorption layer maintains the optical characteristics of the NIR dye (A) at high temperature and is excellent in heat resistance. In addition, in a preferred embodiment, deformation due to heat or stress is less likely to occur, and the adhesion of the dielectric multilayer film is excellent in the present filter. Tg is preferably 200℃or higher, more preferably 250℃or higher. The upper limit of Tg is not particularly limited, but from the viewpoint of molding processability and the like, tg of the transparent resin (P) is preferably 400 ℃ or lower.

The transparent resin (P) is not particularly limited as long as it has a Tg of 130 ℃ or higher and satisfies the requirements (1-1) to (1 to 6) in terms of the relation with the NIR dye (a), and for example, one or more selected from the group consisting of acrylic resins, epoxy resins, olefine thiol resins, polycarbonate resins, polyether resins, polyarylate resins, polysulfone resins, polyethersulfone resins, polyparaphenylene resins, polyarylene ether phosphine oxide resins, polyimide resins, polyamideimide resins, polyolefin resins, cycloolefin resins, and polyester resins can be used.

Among them, at least one or more selected from polyimide resins, polyester resins, polycarbonate resins, cycloolefin resins, and epoxy resins are preferable. From the viewpoint of adhesion to the dielectric multilayer film, a polyimide resin is preferable, and a polyimide resin having a Tg of 200 ℃ or higher is particularly preferable.

The transparent resin (P) may be composed of one kind of resin or two or more kinds of resins. In the case of a composition of two or more resins, it is not necessarily required that the properties of each resin satisfy the requirements of the transparent resin (P), and the mixture satisfies the requirements of the transparent resin (P).

As the transparent resin (P), commercially available ones can be used. The polyester resins are commercially available products, and examples thereof include: OKP4HT, B-OKP-2, OKP-850 (all manufactured by Osaka gas chemical Co., ltd., trade name) and the like.

As the commercially available polycarbonate resin that can be used as the transparent resin (P), there can be mentioned: FPC-0220 (trade name, manufactured by Mitsubishi gas chemical corporation), panlite (trade name, manufactured by Di Kagaku Co., ltd.), PURE-ACE (trade name, manufactured by Di Kagaku Co., ltd.), S5 (trade name, manufactured by Di Kagaku Co., ltd.), and the like.

As the commercially available polyimide resin that can be used as the transparent resin (P), there can be mentioned: neopulim (registered trademark) C-3650 (Mitsubishi gas chemical corporation, trade name), neopulim (registered trademark) C-3G30 (Mitsubishi gas chemical corporation, trade name), neopulim (registered trademark) C-3450 (Mitsubishi gas chemical corporation, trade name), neopulim (registered trademark) P500 (Mitsubishi gas chemical corporation, trade name), JL-20 (New Japan physical manufacturing, trade name) (silica may be contained in the varnish of these polyimide resins), and the like are obtained in the form of a varnish.

The commercially available cycloolefin resins that can be used as the transparent resin (P) include: ARTON (registered trademark) F4520 (trade name manufactured by JSR corporation), ZEONEX (registered trademark) K26R, F, R, T, R, APEL (registered trademark) APL5014DP, APL6015T (all manufactured by samsung chemical corporation, trade name), and the like.

From the viewpoint of maintaining sufficiently high transmittance of visible light, particularly green light and red light, the absorbing layer is preferably composed of only the above-mentioned pigment (a) as an essential pigment, the above-mentioned pigment (B) as an optional pigment, the above-mentioned pigment (C) as an optional pigment, a UV pigment and the like, and the transparent resin (P).

However, the absorbing layer may contain optional components such as a thickener, a color tone correction pigment, a leveling agent, an antistatic agent, a heat stabilizer, a light stabilizer, an antioxidant, a dispersant, a flame retardant, a lubricant, and a plasticizer, within a range that does not impair the effects of the present invention.

When the average OD value in the wavelength range of the maximum absorption wavelength λ _max(A)TR.+ -. 10nm of the NIR dye (A) is set to 1, the absorption layer preferably satisfies the following (2-1) and (2-2), more preferably one or more selected from (2-3) and (2-4), and particularly preferably all of (2-1) to (2-4).

(2-1) The average internal transmittance T _{AVE490-560(AL)} in the wavelength range of 490nm to 560nm is 88% or more. T _{AVE490-560(AL)} is preferably 90% or more, more preferably 92% or more.

(2-2) The average internal transmittance T _{AVE590-630(AL)} in the wavelength range of 590nm to 630nm is 70% or more. T _{AVE590-630(AL)} is preferably 72% or more, more preferably 75% or more.

(2-3) The wavelength lambda _50％.λ_50％ having an internal transmittance of 50% in the wavelength range of 600nm to 700nm, more preferably in the wavelength range of 610nm to 640 nm.

(2-4) The total width of the wavelength regions having an internal transmittance of 30% or less in the wavelength region of 600nm to 1200nm is 250nm or more. In the wavelength range of 600nm to 1200nm, the number of wavelength ranges in which the internal transmittance is 30% or less may be 1 or more. The total width of the wavelength regions having an internal transmittance of 30% or less is preferably 250nm or more, more preferably 300nm or more. The greater the aggregate width, the higher the NIR absorbing capacity of the absorbing layer can be said to be.

The content of the NIR dye (a) in the absorbing layer is appropriately set according to the design of the present filter so that the effect of the present filter can be exerted. The content of the NIR dye (a) in the absorption layer is preferably 1 to 15 parts by mass per 100 parts by mass of the transparent resin (P) from the viewpoint of ensuring the visible light transmittance, particularly the transmittance of green light and red light, and blocking the near infrared light, particularly the near infrared light in the long wavelength range, and the content of the NIR dye (a) in the absorption layer is preferably 1 to 10 parts by mass per 100 parts by mass of the transparent resin (P) from the viewpoint of solubility.

In the case where the absorbing layer contains the NIR dye (a) and one or more selected from the NIR dye (B) and the NIR dye (C), the content of each NIR dye is appropriately selected according to the design of the present filter so that the absorbing layer satisfies the characteristics of (2-1) and (2-2), preferably further satisfies one or more selected from the characteristics of (2-3) and (2-4).

In this case, as described above, the content of the NIR dye (a) in the absorbing layer is preferably 1 to 15 parts by mass, and more preferably 3 to 10 parts by mass, with respect to 100 parts by mass of the transparent resin (P), in terms of ensuring visible light transmittance and exhibiting the characteristics of the NIR dye (B) and the NIR dye (C), with respect to the content of one or more selected from the NIR dye (B) and the NIR dye (C). The total content of the NIR dye (a) and one or more selected from the NIR dye (B) and the NIR dye (C) is preferably 2 to 30 parts by mass, and more preferably 5 to 27 parts by mass from the viewpoint of solubility, relative to 100 parts by mass of the transparent resin (P).

In the present filter, the thickness of the absorption layer is preferably 0.1 μm to 100. Mu.m. When the absorbent layer includes a plurality of layers, the total thickness of the layers is preferably 0.1 μm to 100 μm. When the thickness is less than 0.1 μm, the desired optical characteristics may not be sufficiently exhibited, and when the thickness is more than 100 μm, the flatness of the layer may be lowered, and in-plane variation of the absorption rate may occur. The thickness of the absorption layer is more preferably 0.3 μm to 50. Mu.m. In addition, in the case of having other functional layers such as a reflective layer and an antireflection layer, cracks or the like may occur when the absorption layer is too thick, depending on the material thereof. Therefore, the thickness of the absorption layer is more preferably 0.3 μm to 10. Mu.m.

The absorption layer may be formed, for example, by: the raw material components of the NIR dye (a), preferably the NIR dye (a), and one or more selected from the NIR dye (B) and the NIR dye (C), particularly preferably the NIR dye (a), the NIR dye (B) and the NIR dye (C), the transparent resin (P) or the transparent resin (P), and each component blended as needed are dissolved or dispersed in a solvent to prepare a coating liquid, which is coated on a substrate, dried, and then cured as needed. The substrate may be a transparent substrate included in the present filter, or may be a releasable substrate used only when forming the absorption layer. The solvent may be a dispersion medium capable of stable dispersion or a solvent capable of dissolution.

In addition, the coating liquid may contain a surfactant in order to improve voids due to fine bubbles, pits due to adhesion of foreign matters or the like, shrinkage cavities in the drying process, and the like. In addition, for example, dip coating, casting, spin coating, or the like can be used in the application of the coating liquid. The above-mentioned coating liquid is coated on a substrate, and then dried, thereby forming an absorbent layer. When the coating liquid contains a raw material component of the transparent resin (P), a curing treatment such as thermal curing and photo curing is further performed.

The absorbent layer may be formed into a film shape by extrusion molding, or the film may be laminated on another member and integrated by thermocompression bonding or the like. For example, in the case where the present filter includes a transparent substrate, the film may be adhered to the transparent substrate.

The optical filter may have one or more absorption layers. In the case of having two or more absorbent layers, the respective layers may have the same or different structures. The absorbent layer may be formed of a single layer or may be a multilayer structure. The absorbing layer may function as a substrate (resin substrate) itself.

(Transparent substrate)

In the case of using a transparent substrate for the present filter, the material constituting the transparent substrate is not particularly limited as long as the transparent substrate transmits visible light of about 400nm to about 700nm, and may be a material absorbing near infrared light or near ultraviolet light. Examples thereof include inorganic materials such as glass and crystals, and organic materials such as transparent resins.

Examples of the glass that can be used for the transparent substrate include: copper ion-absorbing glass (near infrared ray-absorbing glass), soda lime glass, borosilicate glass, alkali-free glass, quartz glass, and the like are contained in fluorophosphate glass, phosphate glass, and the like. The term "phosphate glass" also includes a silicophosphate glass having a glass skeleton, a part of which is composed of SiO ₂.

As the glass, a chemically strengthened glass obtained by replacing alkali metal ions (e.g., li ions, na ions) having a small ionic radius, which are present in the main surface of the glass sheet, with alkali metal ions having a larger ionic radius (e.g., na ions or K ions for Li ions, and K ions for Na ions) by ion exchange at a temperature equal to or lower than the glass transition temperature can be used.

As a transparent resin material that can be used as a transparent substrate, there can be mentioned: polyester resins such as polyethylene terephthalate and polybutylene terephthalate; polyolefin resins such as polyethylene, polypropylene and ethylene-vinyl acetate copolymer; norbornene resin; acrylic resins such as polyacrylate and polymethyl methacrylate; polyurethane resin, vinyl chloride resin, fluorine-containing resin, polycarbonate resin, polyvinyl butyral resin, polyvinyl alcohol resin, polyimide resin, and the like.

As a crystal material that can be used for the transparent substrate, birefringent crystals such as quartz crystal, lithium niobate, and sapphire can be mentioned. As for the optical characteristics of the transparent substrate, the optical filter obtained by stacking the absorbing layer, the reflecting layer, and the like may have the optical characteristics. As the crystal material, sapphire is preferable.

The transparent substrate is preferably an inorganic material, and particularly preferably glass or sapphire, from the viewpoints of shape stability related to long-term reliability of optical characteristics, mechanical characteristics, and the like of the filter, handleability at the time of manufacturing the filter, and the like.

The shape of the transparent substrate is not particularly limited, and may be a block, a plate or a film, and the thickness thereof is preferably 0.03mm to 5mm, more preferably 0.03mm to 0.5mm from the viewpoint of thickness reduction. From the viewpoint of workability, a transparent substrate containing glass and having a plate thickness of 0.05mm to 0.5mm is preferable.

(Reflective layer)

The reflective layer contains a dielectric multilayer film and has a function of blocking light of a specific wavelength range. Examples of the reflective layer include: a wavelength selective layer having a wavelength transmitting visible light and reflecting mainly light of a wavelength other than the light shielding region of the absorbing layer. The reflective layer preferably has a reflective region that reflects near infrared light. In this case, the reflection region of the reflection layer may include a light shielding region in the near infrared region of the absorption layer. The reflective layer is not limited to the above characteristics, and may be appropriately designed to further block light in a predetermined wavelength range, for example, light in a near ultraviolet region.

In the case where the reflection layer has a reflection region that reflects near infrared light, specifically, the reflection layer preferably satisfies the following (iii-1).

(Iii-1) the average transmittance T _{RE850-1100AVE0°} of light having a wavelength of 850nm to 1100nm in a spectral transmittance curve at an incident angle of 0 degrees is 0.2% or less.

The average transmittance T _{RE850-1100AVE0°} is preferably 0.15% or less, more preferably 0.05% or less.

In the case where the reflection layer has a reflection region that reflects near infrared light, the absorption layer and the reflection layer preferably have the following relationship.

In the case where the wavelength λ _ABSHT20-0° on the short wavelength side of the absorption layer, which exhibits a transmittance of 20% for light having an incidence angle of 0 degrees, satisfies 650 nm.ltoreq.λ _ABSHT20-0°.ltoreq.800 nm, the relationship between the wavelength λ _ABSHT20-0° and the wavelength λ _RESHT20-0° preferably satisfies (iii-2), the wavelength λ _RESHT20-0° being a wavelength on the short wavelength side of the reflection layer, which exhibits a transmittance of 20% in a wavelength range of 650nm or more for light having an incidence angle of 0 degrees.

(iii-2)λ_ABSHT20-0°+30nm≤λ_RESHT20-0°≤790nm

The reflective layer further preferably satisfies (iii-3).

(Iii-3) an average transmittance of light in a wavelength range from lambda _RESHT20-0° to lambda _RESHT20-0° +300nm is 10% or less.

The reflective layer is composed of a dielectric multilayer film obtained by alternately stacking a dielectric film with a low refractive index (low refractive index film) and a dielectric film with a high refractive index (high refractive index film). The refractive index of the high refractive index film is preferably 1.6 or more, more preferably 2.2 to 2.5. As a material of the high refractive index film, ta ₂O₅、TiO₂、Nb₂O₅, for example, can be cited. Among them, tiO ₂ is preferable from the viewpoints of film forming property, reproducibility of refractive index and the like, stability and the like.

On the other hand, the refractive index of the low refractive index film is preferably less than 1.6, more preferably 1.45 or more and less than 1.55. Examples of the material of the low refractive index film include SiO ₂、SiO_xN_y. SiO ₂ is preferable from the viewpoints of reproducibility of film forming property, stability, economy and the like.

Further, it is preferable that the transmittance of the reflective layer changes steeply in the boundary wavelength range of the transmissive region and the light shielding region. For this purpose, the total number of layers of the dielectric multilayer films constituting the reflective layer is preferably 15 or more, more preferably 25 or more, and still more preferably 30 or more. However, when the total number of layers increases, warpage or the like occurs or the film thickness increases, so that the total number of layers is preferably 100 layers or less, more preferably 75 layers or less, and still more preferably 60 layers or less. The thickness of the dielectric multilayer film is preferably 2 μm to 10 μm.

If the total number of layers and the film thickness of the dielectric multilayer film are within the above-described ranges, the reflective layer satisfies the requirements for miniaturization, and the incident angle dependence can be suppressed while maintaining high productivity. In addition, for example, a vacuum film forming process such as a CVD method, a sputtering method, a vacuum vapor deposition method, or the like can be used for forming the dielectric multilayer film; wet film forming processes such as spray method and dipping method.

The predetermined optical characteristics may be obtained by one reflective layer (a set of dielectric multilayer films), or the predetermined optical characteristics may be obtained by two reflective layers. In the case of having two or more reflective layers, each of the reflective layers may have the same structure or may have different structures. In the case of having two or more reflection layers, the reflection layer is generally composed of a plurality of reflection layers having different reflection bands.

As an example, in the case where two reflective layers are provided, one may be a near infrared reflective layer that blocks light in a short wavelength band in the near infrared region, and the other may be a near infrared and near ultraviolet reflective layer that blocks light in both the long wavelength band and the near ultraviolet region of the near infrared region. In the case where the present filter has a transparent substrate, for example, when two or more reflective layers are provided, all of the reflective layers may be provided on one main surface of the transparent substrate, or each of the reflective layers may be provided on both main surfaces of the transparent substrate so as to sandwich the transparent substrate.

(Antireflection layer)

Examples of the antireflection layer include a dielectric multilayer film, a medium having an intermediate refractive index, and a moth-eye structure having a gradually changing refractive index. Among them, a dielectric multilayer film is preferable from the viewpoints of optical efficiency and productivity. The antireflection layer is obtained by alternately laminating dielectric films like the reflection layer.

The present filter may include, for example, a component (layer) that absorbs inorganic particles or the like that controls transmission and absorption of light in a specific wavelength range, as another component. Specific examples of the inorganic fine particles include ITO (indium tin oxide), ATO (antimony doped tin oxide), cesium tungstate, lanthanum boride, and the like. Since ITO fine particles and cesium tungstate fine particles have high visible light transmittance and light absorptivity in a wide range of an infrared wavelength range of more than 1200nm, they can be used when the infrared light blocking property is required.

In the present filter, the reflection layer and the absorption layer containing the NIR dye (a) and the transparent resin (P) are provided, whereby the visible light transmittance, particularly the transmittance of green light and red light, is well maintained, and the near infrared light blocking property, particularly the long wavelength near infrared light blocking property is excellent.

Regarding the optical characteristics measured under the condition that the incident angle is 0 degrees, it is preferable that the present filter satisfies all of the following requirements (3-1) to (3-3). More preferably, the present filter satisfies all of the requirements (3-4) to (3-9) in addition to the above.

(3-1) The minimum OD value in the wavelength range of the maximum absorption wavelength lambda _max(A)TR.+ -. 10nm of the NIR dye (A) is 4 or more. The minimum OD value at an incident angle of 0 degrees is more preferably 5 or more.

(3-2) The average transmittance T _{AVE490-560(0°)} in the wavelength range of 490nm to 560nm is 82% or more. The average transmittance T _{AVE490-560(0°)} is more preferably 83.0% or more, and still more preferably 83.5% or more.

(3-3) The average transmittance T _{AVE590-630(0°)} in the wavelength range of 590nm to 630nm is 50% or more. The average transmittance T _{AVE590-630(0°)} is more preferably 55% or more, and still more preferably 60% or more.

(3-4) In a wavelength range of 600nm to 800nm, an absolute value of a difference |λ _50％(30°)-λ_50％(0°) | between a wavelength λ _50％(0°) when the transmittance is 50% at an incident angle of 0 degrees and a wavelength λ _50％(30°) when the transmittance is 50% at an incident angle of 30 degrees is 5nm or less. The content of λ _50％(30°)-λ_50％(0°) is more preferably 4nm or less, and still more preferably 3nm or less.

(3-5) The average transmittance T _{AVE490-560(30°)} in a wavelength range of 490nm to 560nm measured at an incident angle of 30 degrees is 80% or more. The average transmittance T _{AVE490-560(30°)} is more preferably 81% or more, and still more preferably 83% or more.

(3-6) The minimum OD value in the wavelength range of the maximum absorption wavelength lambda _max(A)TR.+ -. 10nm of the NIR dye (A) measured at an incident angle of 30 degrees is 3 or more. The minimum OD value at an incident angle of 30 degrees is more preferably 4 or more.

(3-7) In a wavelength range of 600nm to 800nm, an absolute value of a difference |λ _50％(50°)-λ_50％(0°) | between a wavelength λ _50％(0°) when the transmittance is 50% at an incident angle of 0 degrees and a wavelength λ _50％(50°) when the transmittance is 50% at an incident angle of 50 degrees is 15nm or less. The content of λ _50％(50°)-λ_50％(0°) is more preferably 13nm or less, and still more preferably 10nm or less.

(3-8) The average transmittance T _{AVE490-560(50°)} in the wavelength range of 490nm to 560nm measured at an incident angle of 50 degrees is 70% or more. The average transmittance T _{AVE490-560(50°)} is more preferably 72% or more, and still more preferably 74% or more.

(3-9) The minimum OD value in the wavelength range of the maximum absorption wavelength lambda _max(A)TR.+ -. 10nm of the NIR dye (A) measured at an incident angle of 50 degrees is 3 or more. The minimum OD value at an incident angle of 50 degrees is more preferably 4 or more.

The present filter is useful for applications of a filter for an imaging device in an apparatus such as a digital camera having both an imaging device and an optical member using laser light. The present filter is useful for use in optical sensors such as ambient light sensors.

An imaging device using the present filter has a solid-state imaging element, an imaging lens, and the present filter. The present filter can be used, for example, as follows: is arranged between the imaging lens and the solid-state imaging element; or directly attached to a solid-state imaging element, an imaging lens, or the like of an imaging device through an adhesive layer.

Examples

Next, the present invention will be described more specifically by way of examples. First, synthesis examples and characteristics of the NIR dye (a) used in the absorption layer of the example will be described. Next, an embodiment of the filter will be described.

Test examples 1 to 29; synthesis and evaluation of pigment

(Synthesis and evaluation of pigment)

The following methods were used to synthesize NIR dye (a), NIR dye (B), and other NIR dyes. Synthesis examples 1 to 11 are examples of synthesis of NIR dye (A), synthesis examples 12 to 15 are examples of synthesis of NIR dye (B), and synthesis examples 16 and 17 are examples of synthesis of other NIR dyes. Further, trade name S0772 manufactured by FEW CHEMICALS company as a commercial product represented by the following formula (S0772) was prepared as the NIR dye (a), and trade name S2437 manufactured by FEW CHEMICALS company as a commercial product represented by the following formula (S2437) was prepared as the other NIR dye.

Further, ultraviolet-visible spectrophotometers (UH-4150 manufactured by Hitachi high technology Co., ltd.) were used for the evaluation of the optical characteristics of these pigments, and UH-4150 was also used for the evaluation of the following optical characteristics (spectral transmittance curve).

Synthesis example 1

Pigments (A1 a-5 Sb) were synthesized according to the reaction paths shown below.

< Step 1>

To a 1L eggplant-shaped flask were added tris (4-nitrophenyl) amine (25 g, 66 mmol) and palladium-activated carbon (palladium 10%) (6.5 g), 1, 4-dioxane (350 mL), methanol (300 mL), and the mixture was cooled and stirred at 0℃to add ammonium formate (65 g, 990 mmol), and stirred at room temperature for 4 hours. The reaction solution was filtered, and then the filtrate was subjected to extraction operation using methylene chloride, the solvent was removed, 300mL of hexane was added to the remaining solid, and the mixture was stirred for 1 day, followed by washing. Hexane was removed by filtration operation, and as a result, 18.1g (yield 95%) of intermediate 1 was obtained as a gray solid.

< Step 2>

To a 1L eggplant-shaped flask were added intermediate 1 (15 g, 52 mmol), potassium carbonate (71.4 g, 520 mmol), 1-bromo-2-methylpropane (127 g, 930 mmol) and N, N-dimethylformamide (150 mL) obtained in step 1, and the mixture was stirred at 115℃for 24 hours. After the reaction mixture was returned to room temperature, a filtration operation was performed, washing was performed with methylene chloride, the filtrate was extracted with methylene chloride, the solvent was removed, and washing was performed with methanol, whereby 18.2g (yield: 56%) of intermediate 2 was obtained as a brown solid.

< Step 3>

In a 500mL eggplant-shaped flask, intermediate 2 (3 g, 4.8 mmol) obtained in step 2 and N, N-dimethylformamide (60 mL) were added, and stirred at 60℃until dissolved. Then, a solution obtained by dissolving silver hexafluoroantimonate (3.79 g, 11 mmol) in N, N-dimethylformamide (30 mL) was added to the solution obtained by dissolving intermediate 2, and stirred at 60 ℃ for 3 hours. The precipitated solid was filtered, and then the recovered solid was separated by column chromatography (dichloromethane: methanol=1000:30), the solvent was removed, and then a small amount of the solid was dissolved in dichloromethane, and reprecipitation operation was performed using ethyl acetate, whereby 2.8g (yield 54%) of pigment (A1 a-5 Sb) was obtained as a green solid.

Synthesis example 2

In a 500mL eggplant-shaped flask, intermediate 2 (3 g, 4.8 mmol) obtained in step 2 of Synthesis example 1 and ethyl acetate (50 mL) were added, and stirred at 60℃until dissolved. Then, a solution obtained by dissolving potassium bis (trifluoromethylsulfonyl) imide (3.8 g, 12 mmol) and ammonium peroxodisulfate (2.7 g, 12 mmol) in a mixed solvent of acetonitrile (30 mL) and water (30 mL) was added to the solution obtained by dissolving intermediate 2, and stirred at 60 ℃ for 4 hours. After completion of the reaction, the reaction mixture was returned to room temperature, and water (100 mL) and hexane (200 mL) were added thereto to precipitate a solid, which was filtered and washed with ethyl acetate. The recovered solid was separated by column chromatography (dichloromethane: methanol=1000:30), the solvent was removed, and then a small amount of the solid was dissolved in dichloromethane, and reprecipitation operation was performed using ethyl acetate, whereby 3.6g (yield 63%) of pigment (A1 a-5 NS) was obtained as a green solid.

Synthesis example 3

2.6G (yield: 59%) of a pigment (A1 a-5P) was obtained as a green solid in the same manner as in Synthesis example 2, except that potassium bis (trifluoromethylsulfonyl) imide was changed to potassium hexafluorophosphate (2.2 g, 12 mmol).

Synthesis example 4

2.5G (yield 63%) of pigment (A1 a-5 Cl) was obtained as a green solid in the same manner as in Synthesis example 2, except that potassium bis (trifluoromethylsulfonyl) imide was changed to sodium perchlorate (1.5 g, 12 mmol).

Synthesis example 5

2.7G (yield: 71%) of a pigment (A1 a-5B) as a green solid was obtained in the same manner as in Synthesis example 2 except that potassium bis (trifluoromethylsulfonyl) imide was changed to sodium tetrafluoroborate (1.3 g, 12 mmol).

Synthesis example 6

Pigments (A1 a-4P) were synthesized according to the reaction paths shown below.

< Step 1>

The reaction was carried out using the same starting material except that 1-bromo-2-methylpropane used in step 2 of synthesis example 1 was changed to 1-bromobutane (127 g, 930 mmol), the extraction operation was carried out using methylene chloride, and separation was carried out using column chromatography (hexane: ethyl acetate=1000:40), whereby 23g (yield 71%) of intermediate 3 was obtained as a pale yellow oily substance.

< Step 2>

In a 500mL eggplant-shaped flask, intermediate 3 (3 g, 4.8 mmol) obtained in step 1 of Synthesis example 6 and ethyl acetate (50 mL) were added, and stirred at 60℃until dissolved. Then, a solution obtained by dissolving potassium hexafluorophosphate (2.2 g,12 mmol) and ammonium peroxodisulfate (2.7 g,12 mmol) in a mixed solvent of acetonitrile (30 mL) and water (30 mL) was added to the solution obtained by dissolving intermediate 3, and stirred at 60 ℃ for 4 hours. After completion of the reaction, the reaction mixture was returned to room temperature, and water (100 mL) and hexane (200 mL) were added thereto to precipitate a solid, which was filtered and washed with ethyl acetate. The recovered solid was separated by column chromatography (dichloromethane: ethyl acetate=10:1), the solvent was removed, and then a small amount of the solid was dissolved in dichloromethane, and reprecipitation operation was performed using hexane, whereby 2.8g (yield 63%) of pigment (A1 a-4P) was obtained as a green solid.

Synthesis example 7

3.1G (yield: 54%) of a pigment (A1 a-4 NS) as a green solid was obtained in the same manner as in step 2 of Synthesis example 6, except that potassium hexafluorophosphate was changed to potassium bis (trifluoromethylsulfonyl) imide (3.8 g, 12 mmol).

Synthesis example 8

Pigment (A1 a-4B) was obtained as a green solid in the same manner as in step 2 of Synthesis example 6, except that potassium hexafluorophosphate was changed to sodium tetrafluoroborate (1.3 g, 12 mmol).

Synthesis example 9

The pigments (A1 a-7P) were synthesized in the following manner.

< Step 1>

The reaction was carried out using the same starting material except that 1-bromo-2-methylpropane used in step 2 of synthesis example 1 was changed to 1-bromooctane (18 equivalents to intermediate 1), the extraction operation was carried out using methylene chloride, and separation was carried out using column chromatography (hexane: ethyl acetate=1000:40), whereby 13.4g (yield 67%) of intermediate 4 was obtained as a pale yellow oily substance.

< Step 2>

1.0G (yield 20%) of a pigment (A1 a-7P) as a green solid was obtained by the same method except that the intermediate 3 described in step 2 of Synthesis example 6 was changed to the intermediate 4.

Synthesis example 10

The same procedure was repeated except that the potassium hexafluorophosphate used in step 2 of Synthesis example 9 was changed to potassium bis (trifluoromethylsulfonyl) imide, whereby 2.4g (yield: 37%) of a pigment (A1 a-7 NS) was obtained as a green solid.

Synthesis example 11

Pigment (A1 a-1 NS) was synthesized by the following method.

< Step 1>

The reaction was carried out using the same starting material except that 1-bromo-2-methylpropane used in step 2 of synthesis example 1 was changed to bromoethane (18 equivalents relative to intermediate 1), the extraction operation was carried out using methylene chloride, and then separation was carried out using column chromatography (hexane: ethyl acetate=8:2), whereby 1.7g (yield 12%) of intermediate 5 was obtained as a pale yellow oily substance.

< Step 2>

Pigment (A1 a-1 NS) was obtained as a green solid in the same manner except that intermediate 3 in step 2 of Synthesis example 6 was changed to intermediate 5 and potassium hexafluorophosphate was changed to potassium bis (trifluoromethylsulfonyl) imide.

Synthesis example 12

Pigments (B1-5 Sb) were synthesized according to the reaction paths shown below.

< Step 1>

4-Bromide (25.4 g, 148 mmol) and N, N dimethylformamide (80 mL) were added to a 1L eggplant-shaped flask, and the mixture was stirred at 110℃until dissolved. Then, 1-bromo-2-methylpropane (54.7 g, 399 mmol) and N-ethyldiisopropylamine (57.3 g, 444 mmol) were added and reacted at 130℃for 15 hours. Return to room temperature and then use ethyl acetate: hexane=1: 4, and then separated by column chromatography (hexane: ethyl acetate=1000:50), and as a result, 15g (yield 36%) of intermediate 6 was obtained as a white solid.

< Step 2>

To a 1L eggplant-shaped flask were added intermediate 6 (12 g, 42 mmol), 1, 4-phenylenediamine (1.1 g, 9.8 mmol), sodium t-butoxide (8 g, 83 mmol), tris (dibenzylideneacetone) dipalladium (0) (1 g, 1.1 mmol), 2-dicyclohexylphosphino-2 ',4',6' -triisopropylbiphenyl (2 g, 4 mmol), and 1, 4-dioxane (80 mL) obtained in step 1, and the mixture was reacted at 100℃for 20 hours. After the reaction mixture was returned to room temperature, the residual solid of the catalyst was removed by filtration through Celite (Celite), then an extraction operation was performed using saturated methylene chloride and an aqueous ammonium chloride solution, the solvent was removed, and the precipitated solid was washed with methanol, thereby obtaining 17.5g (yield 97%) of intermediate 7 as a brown solid.

< Step 3>

In a 500mL eggplant-shaped flask, intermediate 7 (2 g,2 mmol) obtained in step 2 and N, N-dimethylformamide (20 mL) were added, and stirred at 60℃until dissolved. Then, a solution obtained by dissolving silver hexafluoroantimonate (1.6 g, 4.5 mmol) in N, N-dimethylformamide (20 mL) was added to the solution obtained by dissolving intermediate 7, and stirred at 60 ℃ for 2 hours. The precipitated solid was filtered, then washed with N, N-dimethylformamide, about 150mL of water was slowly dropped into the filtrate, the precipitated solid was filtered again, washed with water and hexane, then separated by column chromatography (dichloromethane: ethyl acetate=7:3), the solvent was removed, and then a small amount of the solid was dissolved in dichloromethane, and reprecipitation operation was performed using ethyl acetate, thereby obtaining 1.3g (yield 43%) of pigment (B1-5 Sb) as a reddish brown solid.

Synthesis example 13

In a 500mL eggplant-shaped flask, intermediate 7 (5 g, 5.4 mmol) obtained in step 2 of Synthesis example 12 and ethyl acetate (50 mL) were added, and stirred at 60℃until dissolved. Then, a solution obtained by dissolving potassium bis (trifluoromethylsulfonyl) imide (4.4 g, 13.8 mmol) and ammonium peroxodisulfate (3.1 g, 13.5 mmol) in a mixed solvent of acetonitrile (30 mL) and water (30 mL) was added to the solution obtained by dissolving intermediate 7, and stirred at 60 ℃ for 4 hours. After completion of the reaction, the reaction mixture was returned to room temperature, and water (100 mL) and hexane (200 mL) were added thereto to precipitate a solid, which was filtered and washed with ethyl acetate. The recovered solid was separated by column chromatography (dichloromethane: methanol=1000:30), the solvent was removed, and then a small amount of the solid was dissolved in dichloromethane, and reprecipitation operation was performed using hexane, whereby 6.0g (yield: 75%) of pigment (B1-5 NS) was obtained as a reddish brown solid.

Synthesis example 14

Pigments (B1-5P) as reddish brown solids were obtained in 36% yield by the same method as in synthesis example 2, except that potassium bis (trifluoromethylsulfonyl) imide was changed to potassium hexafluorophosphate.

Synthesis example 15

An intermediate modified with n-butyl (yield 89%) was synthesized by the same method except that 1-bromo-2-methylpropane used in step 1 of synthesis example 12 was changed to 1-bromobutane (54.7 g, 399 mmol), and pigment (B1-4 Sb) was obtained as a reddish brown solid in 72% yield by the same method as in step 2 and step 3 of synthesis example 12.

Synthesis example 16

The pigment (S1) was synthesized according to the reaction route shown below. That is, the product (10) (6.5 mmol) and squaric acid (3.4 mmol) prepared by reference European Journal of MEDICAL CHEMISTRY,54,647, (2012) were added to a 500mL eggplant-shaped flask, dissolved in toluene (330 mL) and 1-butanol (110 mL), quinoline (8 mmol) was added, and stirred at 150 ℃ for 4 hours. The product (10) was an iodinated salt of a compound in which the 1-position hydrogen of 2-methyl-benzo [ c, d ] indole was replaced with R, and R was-CH ₂-CH(C₆H₁₃)(C₈H₁₇.

After the completion of the reaction, the solvent was removed, and separation was performed by column chromatography (hexane: ethyl acetate=8:2), the solvent was removed, and washing was performed with hexane, whereby pigment (S1) was obtained as a reddish brown solid (0.5 g, yield 25%).

Synthesis example 16

The pigment was synthesized according to the reaction route shown below (S2).

< Step 1>

To a 1L three-necked flask, benzo [ c, d ] indol-2 (1H) -one (30 g, 177 mmol) and chloroform (500 mL) were added, and the mixture was heated and stirred at 65℃to dissolve the starting materials, and then cooled to 0℃to slowly add bromine (28.3 g, 177 mmol) dropwise. After completion of the dropwise addition, the reaction mixture was returned to room temperature and stirred for 24 hours, and then hexane was added to the reaction mixture to dilute the mixture, and the precipitate was collected by filtration. The solid on the filter paper was washed several times with hexane and vacuum-dried, thereby obtaining 60g (yield 100% or more) of intermediate 8 as a earthy yellow solid.

< Step 2>

Into a 1L eggplant-shaped flask were charged intermediate 8 (30 g, 121 mmol), 4-dimethylaminopyridine (2.0 g, 16 mmol), potassium iodide (4.0 g, 24 mmol) and sulfolane (300 mL) synthesized in step 1, and stirred at 70℃for 1 hour. Potassium hydroxide (21 g, 374 mmol) and 7- (bromomethyl) pentadecane (111 g, 363 mmol) were added to the reaction mixture, and the mixture was reacted at 70℃for 19 hours. After the reaction was completed, the reaction was returned to room temperature, and hexane and ethyl acetate were used in an amount of 4:1, and extracting the obtained organic solvent with water to remove the solvent. Then, separation was performed by column chromatography (hexane: ethyl acetate=1000:10), whereby 45g (yield 78%) of intermediate 9 was obtained as a yellow oily substance.

< Step 3>

Into a 1L eggplant-shaped flask were charged intermediate 9 (33 g, 70 mmol), ethyl acetate (2.5 g, 28 mmol), cuprous iodide (I) (1.9 g,10 mmol) and 28% sodium methoxide/methanol solution (42 g) synthesized in step 2, and stirred and reacted at 90℃for 6 hours. Copper (I) iodide (1 g, 5 mmol) and 28% sodium methoxide/methanol solution (20 g) were added thereto, and the mixture was stirred at 90℃for 15 hours. After the completion of the reaction, the reaction mixture was returned to room temperature, filtered through celite, and then extracted with methylene chloride and water to remove the solvent. Then, separation was performed by column chromatography (hexane: ethyl acetate=1000:30), whereby 26g (yield 88%) of intermediate 10 was obtained as a yellow oily substance.

< Step 4>

In a 2L three-necked flask, intermediate 10 (26 g, 61 mmol) synthesized in step 3 and methylene chloride (500 mL) were charged, and cooled to-78 ℃. Then, 1M of a boron tribromide methylene chloride solution (200 mL) was slowly added dropwise, and after the completion of the addition, the reaction solution was returned to room temperature and stirred for 2 hours. After the reaction was completed, the mixture was cooled to 0℃and 200mL of water was slowly added to quench the boron tribromide. The precipitated solid was filtered, and the filtrate was subjected to an extraction operation using methylene chloride and aqueous sodium hydrogencarbonate to remove the solvent. Along with the solid recovered at the time of filtration, washing with hexane was performed a plurality of times, thereby obtaining 24g (yield 95%) of intermediate 11 as a yellow solid.

< Step 5>

In a 1L three-necked flask, intermediate 11 (10 g, 24 mmol), potassium carbonate (16.9 g, 120 mmol) and DMF (120 mL) synthesized in step 4 were charged and stirred at 70 ℃. Then, 7- (bromomethyl) pentadecane (8.95 g, 29 mmol) was added dropwise and stirred at 70℃for 2 hours. After the reaction was completed, hexane and ethyl acetate were used in an amount of 1:1, and extracting the obtained organic solvent with water to remove the solvent. Then, separation was performed by column chromatography (hexane: ethyl acetate=10:1), whereby 14g (yield 91%) of intermediate 12 was obtained as a yellow oily substance.

< Step 6>

In a 1L three-necked flask, intermediate 12 (14 g, 22 mmol), epichlorohydrin (8.2 g, 88 mmol), chloroform (50 mL) and diethyl ether (20 mL) synthesized in step 5 were charged, and stirred at 70 ℃. A mixed solution of boron trifluoride-diethyl etherate (15.9 g, 110 mmol) and chloroform (30 mL) was added dropwise, heated to 130℃and stirred and reacted for 15 hours. Then, the reaction solution was cooled, toluene was added, and the solvent was removed about 2 times by an evaporator, whereby an orange-brown oily substance (intermediate 13') was obtained. To the oily substance were added ethanol (20 mL) and Mirabilitic acid (4.6 g, 32 mmol), triethylamine (11.4 g, 110 mmol) was added, and the mixture was stirred at room temperature for 5 hours. After completion of the reaction, toluene was added, and the solvent was removed by an evaporator about 2 times, followed by separation by column chromatography (hexane: ethyl acetate=6:4), whereby 8g (yield 47%) of intermediate 13 was obtained as a magenta oily substance.

< Step 7>

In a 1L eggplant-shaped flask, intermediate 13 (8 g,10 mmol) synthesized in step 6 and hydrochloric acid (15 mL) were added, and the mixture was heated at 130℃for 1 hour. Then, tetrafluoroboric acid (3 mL) was added and reacted for 1 hour. After the completion of the reaction, the reaction was returned to room temperature, 50mL of water was added, and 20mL of tetrafluoroboric acid was added. Then, an extraction operation was performed using methylene chloride and water, and the solvent was removed, whereby 7.1g (yield 94%) of intermediate 14 was obtained as an orange oily substance.

< Step 8>

In a 1L eggplant-shaped flask, intermediate 14 (7.1 g, 10 mmol), squaric acid (0.59 g, 5.2 mmol), toluene (500 mL), 1-butanol (170 mL) and quinoline (1.77 g) synthesized in step 7 were charged, and reacted at 130℃for 2 hours. Then, the solvent was removed by an evaporator, and separation was performed by column chromatography (hexane: ethyl acetate=9:1), whereby 3.4g (yield 55%) of a pigment was obtained as a black solid (S2).

Using the above-prepared various pigments and transparent resins, a resin layer containing the pigments was prepared, and optical characteristics were measured. Further, various pigments were dissolved in methylene chloride, and the optical characteristics were measured, and compared with those of the resin layer containing the pigments. As the transparent resin, the following commercial products were used. The results are shown in Table 14.

(Transparent resin (P))

Resin a: neopulim (registered trademark) C-3G30 (trade name, manufactured by Mitsubishi gas chemical corporation), varnish containing a polyimide resin, tg of the polyimide resin contained: 320 DEG C

Resin B: ARTON (registered trademark) F4520 (trade name manufactured by JSR corporation), cycloolefin resin, tg:151 DEG C

Resin C: B-OKP-2 (trade name, manufactured by Osaka gas chemical Co., ltd.), polyester resin, tg:150 DEG C

Resin D: OKP-850 (trade name manufactured by osaka gas chemical Co., ltd.), polyester resin, tg:151 DEG C

Resin E: panlite (registered trademark) SP3810 (trade name, manufactured by imperial corporation), polycarbonate resin, tg:150 DEG C

(Other transparent resin)

Resin F: BR50 (trade name manufactured by mitsubishi Yang Zhushi, trade name), acrylic resin, tg:100 DEG C

The prepared dye was uniformly dissolved in the transparent resin dissolved in cyclohexanone so that the solid content concentration of the dye was 10 mass%. The obtained solution was applied to a glass plate (D263: trade name, manufactured by Schottky Co., ltd.) and dried, whereby a resin layer containing a pigment was obtained having a film thickness of about 1. Mu.m. The spectral transmittance curve of the pigment-containing resin layer was obtained from the spectral transmittance curve of the glass plate with the pigment-containing resin layer and the spectral transmittance curve of the glass plate.

The internal transmittance spectrum of the produced pigment-containing resin layer was measured in the wavelength range of 350nm to 1200nm using an ultraviolet-visible near-infrared spectrophotometer, and the internal transmittance T [% ] (% measured transmittance/(100-measured reflectance [% ]) ×100[% ]) was calculated. The amount of pigment (pigment concentration) described in the table is the mass part of pigment relative to 100 mass parts of transparent resin, and the amount is adjusted so that the internal transmittance of light at the maximum absorption wavelength λ _maxTR becomes 10% when the film thickness is 2 μm.

From the spectral transmittance curve adjusted so that the transmittance of light at the maximum absorption wavelength λ _maxTR becomes 10%, the average internal transmittance T _AVE435-480TR of light at the wavelength of 435nm to 480nm, the average internal transmittance T _AVE490-560TR of light at the wavelength of 490nm to 560nm, and the average internal transmittance T _AVE590-630TR of light at the wavelength of 590nm to 630nm were obtained. The width W _T50％ between the wavelengths having the internal transmittance of 50% in the wavelength range of 650nm to 1150nm was obtained. In the table, λ _SH50％ represents a wavelength on the short wavelength side having an internal transmittance of 50% in the wavelength range of 650nm to 1150nm, and λ _LG50％ represents a wavelength on the long wavelength side having an internal transmittance of 50% in the wavelength range of 650nm to 1150 nm.

The maximum absorption wavelength λ _maxDCM was obtained from a spectral transmittance curve obtained by measuring the absorption spectrum of light having a wavelength of 350nm to 1200nm dissolved in methylene chloride. Further, from a spectral transmittance curve obtained by adjusting the dye concentration in methylene chloride so that the transmittance of light at the maximum absorption wavelength λ _maxDCM becomes 10%, the average transmittance T _{AVE435-480DCM} of light at the wavelength of 435nm to 480nm, the average transmittance T _{AVE490-560DCM} of light at the wavelength of 490nm to 560nm, and the average transmittance T _{AVE590-630DCM} of light at the wavelength of 590nm to 630nm were obtained, and the difference between the average transmittance and the average internal transmittance of the dye-containing resin layer was calculated. In the table, T _{AVE435-480DCM}-T_AVE435-480TR is shown in the column "difference between T _AVE435-480". T _{AVE490-560DCM}-T_AVE490-560TR is likewise shown in the column "difference between T _AVE490-560" and T _{AVE590-630DCM}-T_AVE590-630TR is likewise shown in the column "difference between T _AVE590-630".

In addition, FIG. 7 shows the spectral transmittance curves of the pigments (A1 a-5 NS) in test example 2 in the transparent resin (P; resin A) and in methylene chloride. Further, fig. 8 shows the spectral transmittance curves of the pigments (A1 a to 5 NS) in test example 19 in the transparent resin (resin F) and in methylene chloride. In fig. 7 and 9, the range of W _T50％ is indicated by a double arrow in the spectral transmittance curve of the dye measured in the transparent resin.

As is clear from Table 14, the combinations of the NIR dye (A) and the transparent resin (P) in test examples 1 to 18 have the characteristics of (1-1) to (1-6). It is known that the NIR dye (a) is preferably a trisubstituted type ammonium sulfite dye in view of the large absorption width of near infrared light represented by W _T50％. In addition, from the viewpoint of small difference between the optical properties in methylene chloride solution and the optical properties in resin, xa ^- in NIR dye (A) is preferably N [ SO ₂CF₃]₂ ^-、SbF₆ ^- or PF ₆ ^-, particularly preferably N [ SO ₂CF₃]₂ ^- ]. It is known that polyimide resin is preferable as the transparent resin (P) in view of improving the visible light transmittance.

In test examples 19 to 23, it was found that one or more of the characteristics (1-1) to (1-6) were not satisfied because either the NIR dye or the transparent resin did not satisfy the requirements of the NIR dye (A) or the transparent resin (P). Test examples 24 to 28 are examples in which the pigment (B1) was combined with the transparent resin (P) or a transparent resin that did not satisfy the requirements of the transparent resin (P), and it is found that the pigment (B1) better functions as the NIR pigment (B) by being combined with the transparent resin (P) such as a polyimide resin.

Examples 1 to 11; manufacture and evaluation of optical Filter

(Manufacture of optical Filter)

A filter having the same structure as the filter 10B shown in fig. 2 was manufactured and evaluated by the following method. The structure of the filter and the evaluation results are shown in table 15. Examples 1 to 7 are examples, and examples 8 to 11 are comparative examples.

In each example, a fluorophosphate glass substrate (manufactured by AGC Co., ltd., thickness: 0.2 mm) containing CuO, or a Di human PURE-ACE WRM5-80 (manufactured by Di human Co., ltd., trade name: polycarbonate resin, tg: 215 ℃) resin substrate having a thickness of 0.08mm was used as the transparent substrate. The tables are respectively referred to as "absorption glass" and "PC resin",

As the reflective layer, a dielectric multilayer film formed as follows was used. The dielectric multilayer film is formed by alternately stacking 42 layers of TiO ₂ films and SiO ₂ films on one main surface of a transparent substrate by vapor deposition. The structure of the reflective layer is designed in the following way: the number of layers of dielectric multilayer films, the film thickness of the TiO ₂ film, and the film thickness of the SiO ₂ film were simulated as parameters, and the average transmittance of light having a wavelength of 850nm to 1100nm was 0.03% in a spectral transmittance curve having an incident angle of 0 degrees.

On the main surface of the glass substrate opposite to the surface on which the reflective layer was formed, the transparent resin shown in the table, the NIR dye (a), the NIR dye (B), the NIR dye (C) (dye I-12-23), and other NIR dyes were combined to form an absorbing layer having a thickness of about 2.0 μm. Here, the maximum absorption wavelength lambda _max(C)TR of the dye (I-12-23) in the spectral transmittance curve of 350nm to 1200nm measured by incorporating it in the resin A is 714nm.

The content of the pigment in the table is the mass part of the pigment per 100 mass parts of the transparent resin.

As other NIR pigments, the following pigments (15), pigments (16) and pigments (17) are used. The dye (15) is a dye which has a maximum absorption wavelength lambda _max(A)TR of 937nm in a spectral transmittance curve of 350nm to 1200nm measured by inclusion in the resin A, but does not satisfy the characteristics of (1-4). The maximum absorption wavelengths lambda _maxTR of the pigments (16) and (17) in the spectral transmittance curves of 350nm to 1200nm measured by including them in the resin F are 839nm and 771nm, respectively.

[ Synthesis of pigment (15) ]

Pigment (15) was synthesized according to the reaction route shown below.

< Step b1>

To the flask were added 2-bromothiophene (9.00 g, 55.2 mmol), magnesium (4.03 g, 165 mmol), and dissolved in anhydrous tetrahydrofuran (55 mL) under a nitrogen atmosphere. The above mixed solution was stirred at 80℃for 1 hour. In another flask was added [1, 3-bis (diphenylphosphino) propane ] nickel (II) dichloride (1.20 g, 2.21 mmol), 2, 3-dibromothiophene (12.7 g, 52.5 mmol) and dissolved in anhydrous diethyl ether (110 mL). The above ether mixed solution was cooled to 0 ℃, and the above tetrahydrofuran mixed solution was added dropwise thereto, followed by stirring at room temperature for 3 hours. After completion of the reaction, water (55 mL) was added to the above mixed solution, followed by extraction with ethyl acetate, the organic layer was washed with saturated brine, the solvent was removed, and intermediate A3-11 (8.93 g, yield 66%) was obtained by column chromatography (hexane).

< Step b2>

To the flask was added intermediate A3-11 (8.09 g, 33 mmol) obtained in step b1, and the mixture was dissolved in anhydrous diethyl ether (230 mL) under a nitrogen atmosphere. The above solution was cooled to-78℃and 1.6M n-butyllithium hexane solution (20 mL, 32.0 mmol) was added dropwise and stirred for 1 hour. Subsequently, an anhydrous diethyl ether solution (120 mL) in which benzophenone (6.56 g, 36.0 mmol) was dissolved was added dropwise. The above mixed solution was stirred at room temperature for 1 day. After completion of the reaction, a saturated aqueous ammonium chloride solution (200 mL) was added, and extraction was performed with diisopropyl ether. The obtained organic layer was washed with saturated brine, and the solvent was removed, whereby intermediate A3-12 (8.81 g, yield 77%) was obtained by column chromatography (hexane: dichloromethane=1:1).

< Step b3>

To the flask were added intermediate A3-12 (4.94 g, 14.4 mmol) obtained in step b2, amberlyst 15 (2.30 g) and dissolved in anhydrous toluene (300 mL) under nitrogen atmosphere. The above mixed solution was stirred under reflux for 7 hours. After the completion of the reaction, the mixture was filtered to obtain a filtrate, and the solvent was removed to obtain intermediate A3-13 (4.29 g, 91%) by column chromatography (hexane: dichloromethane=2:1).

< Step b4>

To the flask was added intermediate A3-13 (4.00 g, 12.1 mmol) obtained in step b3, and the mixture was dissolved in anhydrous dimethylformamide (120 mL) under a nitrogen atmosphere. To the above solution was added dropwise an anhydrous dimethylformamide solution (30 mL) in which N-bromosuccinimide (2.16 g, 12.1 mmol) was dissolved. The above mixed solution was stirred at room temperature for one day. After the completion of the reaction, the mixture was poured into ice water and extracted with diisopropyl ether. The obtained organic layer was washed with saturated brine, and the solvent was removed, followed by column chromatography (dichloromethane) to obtain intermediate A3-14 (3.67 g, yield 74%).

< Step b5>

The flask was charged with intermediate A3-14 (3.50 g, 8.55 mmol) obtained in step b4, and magnesium (0.416 g, 17.1 mmol) in the form of chips, and dissolved in anhydrous tetrahydrofuran (20 mL) under a nitrogen atmosphere. The solution was refluxed for 3 hours and cooled to-40 ℃. In another flask, N-chlorosuccinimide (1.03 g, 7.70 mmol) was dissolved in anhydrous toluene (20 mL) under nitrogen, bis (2-ethylhexyl) amine (1.86 g, 7.70 mmol) was added, and stirred for 20 minutes.

To the mixed solution cooled to-40℃was added dropwise tetraisopropyl orthotitanate (2.43 g, 8.55 mmol), and stirred for 5 minutes, followed by adding dropwise a mixed solution of N-chlorosuccinimide and bis (2-ethylhexyl) amine. After stirring at room temperature for 3 hours, a saturated aqueous potassium carbonate solution (17 mL) was added. The resulting solution was then diluted with ethyl acetate and filtered, and extracted with ethyl acetate. The obtained organic layer was washed with saturated brine, and the solvent was removed, whereby intermediate A3-15 (1.34 g, yield 27.5%) was obtained by column chromatography (hexane: triethylamine=100:3).

< Step b6>

To a flask were added intermediate A3-15 (1.30 g, 2.28 mmol) obtained in step b5, 3, 4-dihydroxy-3-cyclobutene-1, 2-dione (0.130 g, 1.14 mmol), which was dissolved in a mixed solution of n-butanol (6 mL) and toluene (6 mL) under nitrogen atmosphere, and after the completion of the reaction, the solvent was removed by reflux stirring for 3 hours, and pigment (15) (0.445 g, yield 32%) was obtained by column chromatography (dichloromethane: methanol: triethylamine=100:1:3).

[ Synthesis of pigment (16) and pigment (17) ]

Pigment (16) and pigment (17) were synthesized by the method described in j.

(Evaluation)

< Optical Properties of absorption layer >

The spectral transmittance curves at an incident angle of 0 degrees were obtained for the absorption layers of the obtained filters of examples 1 to 11. In this spectral transmittance curve, the average internal transmittance T _{AVE435-480(AL)} in the wavelength range of 435nm to 480nm, the average internal transmittance T _{AVE490-560(AL)} in the wavelength range of 490nm to 560nm, and the average internal transmittance T _{AVE590-630(AL)} in the wavelength range of 590nm to 630nm were obtained when the average OD value in the wavelength range of the maximum absorption wavelength λ _max(A)TR ±10nm of the NIR dye (a) was set to 1.

Further, the total width of the wavelength regions (the "width of T _30％ or less" in the table) in which the internal transmittance in the wavelength region of 600nm to 800nm was 50% and the internal transmittance in the wavelength region of 600nm to 1200nm was 30% or less, when the average OD value in the wavelength region of the NIR dye (a) in the wavelength region of the maximum absorption wavelength λ _max(A)TR ±10nm was 1, was obtained. The transmittance T ₅₀₀ at the wavelength of 500nm and the transmittance T ₆₀₀ at the wavelength of 600nm are shown together in the table.

< Optical Property of Filter >

Further, the spectral transmittance curves at the incident angles of 0 degrees, 30 degrees, and 50 degrees were obtained for the obtained filters of examples 1 to 11, and the following optical characteristics were obtained.

The minimum OD value in the wavelength range of the NIR dye (A) having the maximum absorption wavelength λ _max(A)TR.+ -. 10nm at the incidence angle of 0 degrees, the average transmittance T _{AVE435-480(0°)} in the wavelength range of 435nm to 480nm at the incidence angle of 0 degrees, the average transmittance T _{AVE490-560(0°)} in the wavelength range of 490nm to 560nm at the incidence angle of 0 degrees, the average transmittance T _{AVE590-630(0°)} in the wavelength range of 590nm to 630nm at the incidence angle of 0 degrees, and the wavelength λ _50％(0°) in the wavelength range of 600nm to 800nm at the incidence angle of 0 degrees were obtained.

The minimum OD value in the wavelength range of the maximum absorption wavelength lambda _max(A)TR.+ -. 10nm of the NIR dye (A) at an incidence angle of 30 degrees was determined; an absolute value |λ _50％(30°)-λ_50％(0°) | of a difference between a wavelength λ _50％(0°) at which the transmittance is 50% at an incident angle of 0 degrees and a wavelength λ _50％(30°) at which the transmittance is 50% at an incident angle of 30 degrees in a wavelength range of 600nm to 800 nm; an average transmittance T _{AVE490-560(30°)} in a wavelength range of 490nm to 560nm at an incident angle of 30 degrees.

The minimum OD value in the wavelength range of the maximum absorption wavelength lambda _max(A)TR.+ -. 10nm of the NIR dye (A) at an incident angle of 50 degrees was determined; an absolute value |λ _50％(50°)-λ_50％(0°) | of a difference between a wavelength λ _50％(0°) at which the transmittance is 50% at an incident angle of 0 degrees and a wavelength λ _50％(50°) at which the transmittance is 50% at an incident angle of 50 degrees in a wavelength range of 600nm to 800 nm; an average transmittance T _{AVE490-560(50°)} in a wavelength range of 490nm to 560nm at an incident angle of 50 degrees.

Fig. 9 and 10 show the spectral transmittance curves of the absorption layer and the filter in the filter according to the embodiment of example 1, fig. 11 and 12 show the spectral transmittance curves of the absorption layer and the filter in the filter according to the embodiment of example 4, and fig. 13 and 14 show the spectral transmittance curves of the absorption layer and the filter in the filter according to the embodiment of example 6. Fig. 15 and 16 show spectral transmittance curves of the absorption layer and the filter in the filter of the comparative example of example 8. In the graph of the spectral transmittance curve of the absorption layer of each example, W or Wa and Wb are denoted "width of T _30％ or less". In examples 4, 6 and 8, the "width of T _30％ or less" is the sum of Wa and Wb.

As is clear from table 15, fig. 10, fig. 12, and fig. 14, the filters of the examples 1 to 7 are capable of maintaining sufficiently high visible light transmittance, particularly transmittance of green light and red light, and are particularly excellent in blocking property of near infrared light, particularly blocking property of long wavelength near infrared light.

The present application has been described in detail and with reference to specific embodiments, but it will be apparent to one skilled in the art that various changes or modifications can be made without departing from the spirit and scope of the application. The present application is based on japanese patent application (japanese patent application publication No. 2019-114575), filed on 6/20 of 2019, the contents of which are incorporated herein by reference.

Industrial applicability

The filter of the present invention can maintain a sufficiently high visible light transmittance, particularly transmittance of green light and red light, and is excellent in blocking property of near infrared light, particularly blocking property of long-wavelength near infrared light. According to the present invention, an imaging device and an optical sensor excellent in color reproducibility and durability using the filter can be provided.

Description of the reference numerals

10A, 10B, 10C, 10D, 10E, 10F … … filters; 11. 11a, 11b … … absorbent layers; 12. 12a, 12b … … reflective layers; 13 … … transparent substrates; 14 … … antireflection layer.

Claims (18)

1. The optical filter comprises an absorption layer and a reflection layer, wherein the absorption layer contains a near infrared ray absorption pigment (A) and a transparent resin with a glass transition temperature of 130 ℃ or higher, the reflection layer comprises a dielectric multilayer film, and the near infrared ray absorption pigment (A) satisfies all the following requirements (1-1) to (1-6):

(1-1) in a spectral transmittance curve SC _TR having a wavelength of 350nm to 1200nm measured by including the near infrared ray absorption dye (a) in the transparent resin, a maximum absorption wavelength λ _max(A)TR is in a wavelength range of 850nm to 1100 nm;

(1-2) in the spectral transmittance curve SC _TR, when the internal transmittance at the maximum absorption wavelength λ _max(A)TR is 10%, the average internal transmittance T _{AVE490-560(A)TR} of light having a wavelength of 490nm to 560nm is 90% or more;

(1-3) in the spectral transmittance curve SC _TR, when the internal transmittance at the maximum absorption wavelength λ _max(A)TR is 10%, the average internal transmittance T _{AVE590-630(A)TR} of light having a wavelength of 590nm to 630nm is 90% or more;

(1-4) in the spectral transmittance curve SC _TR, when the internal transmittance at the maximum absorption wavelength λ _max(A)TR is 10%, having two wavelengths in which the internal transmittance is 50% in the wavelength range of 650nm to 1150nm, and a width between the wavelengths in which the two internal transmittances are 50% is 180nm or more;

(1-5) in a spectral transmittance curve SC _DCM having a wavelength of 350nm to 1200nm, measured by dissolving the near-infrared ray absorption dye (a) in methylene chloride, when the transmittance of light at the maximum absorption wavelength λ _max(A)DCM is 10%, the value obtained by subtracting the average internal transmittance T _{AVE490-560(A)TR} from the average transmittance T _{AVE490-560(A)DCM} of light at the wavelength of 490nm to 560nm is 10% or less;

(1-6) in the spectral transmittance curve SC _DCM, when the transmittance of light at the maximum absorption wavelength lambda _max(A)DCM is 10%, the value obtained by subtracting the average internal transmittance T _{AVE590-630(A)TR} from the average transmittance T _{AVE590-630(A)DCM} of light at the wavelengths of 590nm to 630nm is 10% or less,

The absorbent layer satisfies the following requirements (2-4):

(2-4) the total width of the wavelength regions having an internal transmittance of 30% or less in the wavelength region of 600nm to 1200nm is 250nm or more.

2. The optical filter according to claim 1, wherein the near infrared ray absorbing pigment (a) further satisfies one or more conditions selected from the following (1-7) to (1-9):

(1-7) a value obtained by subtracting an average transmittance T _{AVE435-480(A)DCM} of light having a wavelength of 435nm to 480nm in the spectral transmittance curve SC _DCM when the transmittance of light having the maximum absorption wavelength λ _max(A)DCM is 10% from an average internal transmittance T _{AVE435-480(A)TR} of light having a wavelength of 435nm to 480nm in the spectral transmittance curve SC _TR when the internal transmittance at the maximum absorption wavelength λ _max(A)TR is 10%;

(1-8) the average transmittance T _{AVE490-560(A)DCM} minus the average internal transmittance T _{AVE490-560(A)TR} is 5% or less;

(1-9) the value obtained by subtracting the average internal transmittance T _{AVE590-630(A)TR} from the average transmittance T _{AVE590-630(A)DCM}% or less.

3. The optical filter according to claim 1 or 2, wherein the near infrared ray absorption pigment (A) is at least one compound selected from the group consisting of a compound represented by the following formula (A1) and a compound represented by the following formula (A2),

The symbols in the formulae (A1) and (A2) are as follows:

R ²⁰¹～R²⁰⁶ and R ²²¹～R²²⁶ are each independently a hydrogen atom, a halogen atom, a sulfo group, a hydroxyl group, a cyano group, a nitro group, a carboxyl group, a phosphoric acid group, an alkyl group having 1 to 20 carbon atoms which may have an oxygen atom and may be substituted between carbon atoms, or an alkoxy group having 1 to 20 carbon atoms which may have an oxygen atom and may be substituted between carbon atoms, or an aryl group having 6 to 14 carbon atoms which may be substituted, an aralkyl group having 7 to 14 carbon atoms which may be substituted, or a heterocyclic group having 3 to 14 carbon atoms which may be substituted, wherein a group having a substituted or unsubstituted amino group bonded to a phenyl group is not included, and furthermore, in R ²⁰¹～R²⁰⁶ and R ²²¹～R²²⁶, 2 groups bonded to the same nitrogen atom may be bonded to each other and form a 3-to 8-membered heterocyclic ring together with the nitrogen atom, and the hydrogen atom bonded to the ring may be substituted with an alkyl group having 1 to 12 carbon atoms;

R ²⁰⁷～R²¹⁸ and R ²²⁷～R²³⁸ are each independently a hydrogen atom, a halogen atom, an amino group which may be substituted, an amide group, a cyano group, a nitro group, a carboxyl group, or an alkyl group having 1 to 12 carbon atoms which may be substituted with a halogen atom or an alkoxy group having 1 to 12 carbon atoms which may be substituted with a halogen atom, in R ²⁰⁷～R²¹⁸ and R ²²⁷～R²³⁸, 2 groups adjacent to each other may be bonded to each other and form a 3-to 8-membered ring together with 2 carbon atoms of the phenyl group, and the hydrogen atom bonded to the ring may be substituted with an alkyl group having 1 to 12 carbon atoms;

In addition, R ²⁰¹ and R ²⁰⁷、R²⁰² and R ²¹⁰、R²⁰³ and R ²¹¹、R²⁰⁴ and R ²¹⁴、R²⁰⁵ and R ²¹⁵、R²⁰⁶ and R ²¹⁸、R²²¹ and R ²²⁷、R²²² and R ²³⁰、R²²³ and R ²³¹、R²²⁴ and R ²³⁴、R²²⁵ and R ²³⁵、R²²⁶ and R ²³⁸ may be bonded to each other and form a 4-to 8-membered heterocyclic ring together with the nitrogen atom bonded to the phenyl group and the 2 carbon atoms of the phenyl group, and the hydrogen atom bonded to the ring may be substituted with an alkyl group having 1 to 12 carbon atoms;

Xa ^- and Xb ^- each independently represent a monovalent anion.

4. The optical filter according to claim 3, wherein the near infrared ray absorbing pigment (a) is at least one compound selected from the group consisting of a compound represented by the formula (A1) and the Xa ^- is N [ SO ₂CF₃]₂ ^-、SbF₆ ^- or PF ₆ ^- and a compound represented by the formula (A2) and the Xb ^- is N [ SO ₂CF₃]₂ ^-、SbF₆ ^- or PF ₆ ^-.

5. The optical filter according to any one of claims 1 to 4, wherein the transparent resin is at least one resin selected from polyimide resins, polyester resins, polycarbonate resins, cycloolefin resins, and epoxy resins.

6. The optical filter according to any one of claims 1 to 5, wherein the transparent resin is a polyimide resin.

7. The optical filter according to any one of claims 1 to 6, wherein the absorbing layer further contains a near infrared ray absorbing dye (B) having a maximum absorption wavelength in a wavelength range of 1100nm to 1200nm in a spectral transmittance curve of 350nm to 1200nm measured by including the near infrared ray absorbing dye (B) in the transparent resin.

8. The optical filter according to claim 7, wherein the near infrared ray absorption pigment (B) contains at least one compound selected from the group consisting of a compound represented by the following formula (B1) and a compound represented by the following formula (B2),

The symbols in the formulae (B1) and (B2) are as follows:

R ²⁴¹～R²⁴⁸ and R ²⁶¹～R²⁶⁸ are each independently a hydrogen atom, a halogen atom, a sulfo group, a hydroxyl group, a cyano group, a nitro group, a carboxyl group, a phosphoric acid group, an alkyl group having 1 to 20 carbon atoms which may have an unsaturated bond or an oxygen atom between carbon atoms and may be substituted, or an alkoxy group having 1 to 20 carbon atoms which may have an unsaturated bond or an oxygen atom between carbon atoms and may be substituted, or an aryl group having 6 to 14 carbon atoms which may be substituted, an aralkyl group having 7 to 14 carbon atoms which may be substituted, or a heterocyclic group having 3 to 14 carbon atoms which may be substituted, in R ²⁴¹～R²⁴⁸ and R ²⁶¹～R²⁶⁸, 2 groups bonded to the same nitrogen atom may be bonded to each other and form a heterocyclic ring having 3 to 8 carbon atoms together with the nitrogen atom, and the hydrogen atom bonded to the ring may be substituted with an alkyl group having 1 to 12 carbon atoms;

R ²⁴⁹～R²⁵³ and R ²⁶⁹～R²⁷³ are each independently a hydrogen atom, a halogen atom, an amino group which may be substituted, an amide group, a cyano group, a nitro group, a carboxyl group, or an alkyl group having 1 to 12 carbon atoms which may be substituted with a halogen atom or an alkoxy group having 1 to 12 carbon atoms which may be substituted with a halogen atom, and four of each of R ²⁴⁹～R²⁵³ may be the same or different, and four of each of R ²⁶⁹～R²⁷³ may be the same or different;

xc ^- and Xd ^- each independently represent a monovalent anion.

9. The optical filter according to any one of claims 1 to 8, wherein the absorbing layer further contains a near infrared ray absorbing dye (C) having a maximum absorption wavelength in a wavelength range of 630nm to 750nm in a spectral transmittance curve of 350nm to 1200nm measured by including the near infrared ray absorbing dye (C) in the transparent resin.

10. The filter according to any one of claims 1 to 9, wherein when an average OD value in a wavelength range of a maximum absorption wavelength λ _max(A)TR ±10nm of the near infrared ray absorption pigment (a) is set to 1, the absorption layer satisfies the following (2-1) and (2-2):

(2-1) an average internal transmittance T _{AVE490-560(AL)} in a wavelength range of 490nm to 560nm of 88% or more;

(2-2) the average internal transmittance T _{AVE590-630(AL)} in the wavelength range of 590nm to 630nm is 70% or more.

11. The optical filter according to claim 10, wherein when an average OD value in a wavelength range of a maximum absorption wavelength λ _max(A)TR ±10nm of the near infrared ray absorption pigment (a) is set to 1, the absorption layer satisfies the following requirement (2-3):

(2-3) a wavelength lambda _50％ having an internal transmittance of 50% in a wavelength range of 600nm to 700 nm.

12. The filter according to any one of claims 1 to 11, wherein the filter further has a transparent substrate, and the absorption layer and the reflection layer are provided on main surfaces of the transparent substrate, respectively.

13. The filter of claim 12, wherein the transparent substrate comprises transparent resin or glass.

14. The optical filter according to claim 13, wherein the glass is copper ion-added fluorophosphate glass or copper ion-added phosphate glass.

15. The optical filter according to any one of claims 1 to 14, wherein the optical characteristics of the optical filter measured at an incident angle of 0 degrees satisfy all of the following requirements (3-1) to (3-3):

(3-1) a minimum OD value of 4 or more in a wavelength range of a maximum absorption wavelength λ _max(A)TR ±10nm of the near infrared ray absorption dye (a);

(3-2) an average transmittance T _{AVE490-560(0°)} in a wavelength range of 490nm to 560nm of 82% or more;

(3-3) the average transmittance T _{AVE590-630(0°)} in the wavelength range of 590nm to 630nm is 50% or more.

16. The filter according to claim 15, wherein the filter further satisfies all of the following requirements (3-4) to (3-9):

(3-4) an absolute value |λ _50％(30°)-λ_50％(0°) | of a difference between a wavelength λ _50％(0°) when the transmittance is 50% at an incident angle of 0 degrees and a wavelength λ _50％(30°) when the transmittance is 50% at an incident angle of 30 degrees in a wavelength range of 600nm to 800nm is 5nm or less;

(3-5) an average transmittance T _{AVE490-560(30°)} of 80% or more in a wavelength range of 490nm to 560nm measured at an incident angle of 30 degrees;

(3-6) a minimum OD value of 3 or more in a wavelength range of a maximum absorption wavelength λ _max(A)TR ±10nm of the near infrared ray absorption dye (a) measured at an incident angle of 30 degrees;

(3-7) an absolute value |λ _50％(50°)-λ_50％(0°) | of a difference between a wavelength λ _50％(0°) at which the transmittance is 50% at an incident angle of 0 degrees and a wavelength λ _50％(50°) at which the transmittance is 50% at an incident angle of 50 degrees in a wavelength range of 600nm to 800nm is 15nm or less;

(3-8) an average transmittance T _{AVE490-560(50°)} in a wavelength range of 490nm to 560nm measured at an incident angle of 50 degrees of 70% or more;

(3-9) a minimum OD value of 3 or more in a wavelength range of a maximum absorption wavelength lambda _max(A)TR.+ -. 10nm of the near infrared ray absorption dye (A) measured at an incident angle of 50 degrees.

17. An imaging device, wherein the imaging device has the optical filter of any one of claims 1 to 16.

18. An optical sensor, wherein the optical sensor has the optical filter of any one of claims 1 to 16.