CN111201137A

CN111201137A - Film

Info

Publication number: CN111201137A
Application number: CN201880065702.4A
Authority: CN
Inventors: 真锅功; 荘司秀夫; 田中照也
Original assignee: Toray Industries Inc
Current assignee: Toray Industries Inc
Priority date: 2017-10-10
Filing date: 2018-09-11
Publication date: 2020-05-26
Anticipated expiration: 2038-09-11
Also published as: JP7200675B2; TWI778136B; WO2019073737A1; JP7424461B2; KR20200062080A; JP2023026489A; JPWO2019073737A1; TW201922506A; CN111201137B; KR102633961B1

Abstract

Provided is a film which can transfer a uniform low-gloss appearance independent of an incident angle when used as a transfer film, and which has a 60 DEG gloss (G)₆₀) And 85 ° gloss (G)₈₅) A film of a low gloss layer (layer A) having a gloss of not more than 27, the above 60 DEG gloss (G)₆₀) And the above 85 DEG gloss (G)₈₅) Satisfies the condition that G is less than or equal to 0.1₈₅)/(G₆₀)≤3。

Description

Film

Technical Field

The present invention relates to membranes.

Background

In recent years, high precision and high density of printed wiring boards have been developed by integration of circuits accompanying expansion of smart phones and flat panels. In a process for manufacturing a printed wiring board, after a circuit is provided on a surface of an insulating base material (polyimide resin, polyphenylene sulfide resin, or the like), a covering layer of a heat-resistant resin film having an adhesive layer is covered for the purpose of insulation and circuit protection, and the printed wiring board is molded by pressure lamination through a mold release film. In this case, the release film is required to have not only releasability from a printed wiring board material or a press plate, shape following property, and uniform moldability, but also a property (matte appearance transferability) of transferring a matte appearance (low gloss appearance) to a release target. Further, even in a transfer film in which functional layers such as an insulating layer, a hard coat layer, and an electromagnetic wave shielding layer are transferred onto the surface of a circuit substrate by heating and pressing, there is an increasing demand for a film having a matte appearance transferability.

Conventionally, as a release film and a transfer film having a matte appearance transferability, a processed product such as a sandblasted film, a Chemical matte (Chemical mat), a coated matte (Coating mat) and the like has been generally used, but it is desired to improve problems concerning cost increase and quality due to an increase in the number of steps. As a method for solving these problems, a particle-doped film produced by a method of extruding a large amount of particles together with a resin has been proposed. (for example, patent documents 1 and 2). Further, as a film having a high matte appearance, a film having a resin layer provided on the surface thereof by coating has been proposed (for example, patent document 3).

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2016-97522

Patent document 2: japanese patent laid-open No. 2014-24341

Patent document 3: japanese patent laid-open publication No. 2005-24942

Disclosure of Invention

Problems to be solved by the invention

The films described in patent documents 1,2, and 3 can reduce the gloss to some extent, but it is difficult to achieve a low gloss appearance independent of the incident angle, which has been required in recent years.

The object of the present invention is to eliminate the problems of the prior art described above. That is, when used as a transfer film, a film capable of transferring a uniform low gloss appearance regardless of the incident angle is provided.

Means for solving the problems

In order to solve the above problems, the film of the present invention has the following configuration.

(1) A film having a 60 DEG gloss (G)₆₀) And 85 DEG gloss (G)₈₅) A low gloss layer (layer A) having a gloss value of 27 or less, wherein the layer A is located on at least one surface layer and the 60 DEG gloss value (G) is₆₀) And the above 85 DEG gloss (G)₈₅) Satisfies the following formula (I).

0.1≤(G₈₅)/(G₆₀)≤3···(I)

(2) The film according to (1), wherein the low gloss layer (layer A) has a 60 DEG gloss (G)₆₀) And 85 DEG gloss (G)₈₅) Are all 10 or less.

(3) The film according to (1) or (2), wherein the variation in tensile break strength of the film in the range of 20cm X30 cm is 20% or less.

(4) The film according to any one of (1) to (3), which has a base material layer on the side of the layer A.

(5) The film according to (4), wherein the base layer and the layer A both comprise a polyester resin as a main component.

(6) The film according to any one of (1) to (5), wherein the thickness of the layer A is more than 3 μm and 20 μm or less.

(7) The film according to any one of (1) to (6), wherein the layer A contains particles, the particles have an average particle diameter of 1.5 μm or more and 15 μm or less, the content of the particles is more than 18% by mass and 40% by mass, based on 100% by mass of the entire layer A.

(8) The film according to any one of (1) to (6), wherein the layer A contains particles, the particles have an average particle diameter of 3 to 15 μm, the total amount of the layer A is 100% by mass, and the content of the particles is 18 to 40% by mass.

(9) The film according to (7) or (8), wherein the particles have a circularity of 0.995 or less.

(10) The film according to (7) or (8), wherein the particle circularity is 0.995 or less and the bulk height is 0.5 or more.

(11) The film according to any one of (1) to (10), which has a 60 ° gloss (G)₆₀) Less than 6.

(12) The film according to any one of (1) to (11), wherein the number of MIT bend breakages in at least one of the longitudinal direction (MD) and the width direction (TD) is 7500 or more.

(13) The film according to any one of (1) to (12), wherein the thermal dimensional change rate in the range of 100 ℃ to 150 ℃ in both the longitudinal direction (MD) and the width direction (TD) is 0.015%/° C or less.

(14) The film according to any one of (1) to (13), wherein the center line average roughness (SRa) of the surface of the layer A is more than 1000nm and 3000nm or less.

(15) The film according to any one of (1) to (14), wherein the heat shrinkage rates at 150 ℃ in both the longitudinal direction (MD) and the width direction (TD) are 2% or less.

(16) The film according to any one of (1) to (15), wherein a curl height after heat treatment at 150 ℃ for 10 minutes is 0mm or more and 30mm or less as measured by the following method.

(measurement method) the film was cut into a size of 100mm in length in any one direction and 100mm in length in a direction orthogonal to the direction, and the cut film was used as a sample. The sample was left to stand in a hot air circulating oven at 150 ℃ for 10 minutes for heat treatment, and then placed on a glass plate, the amount of lifting from the surface of the glass plate at four corners in the vertical direction was measured, and the maximum height was defined as the curl height.

(17) The film according to any one of (1) to (16), wherein the surface free energy of the surface of the layer A is 44mN/m or less.

(18) The film according to any one of (1) to (17), which is used for transfer application.

(19) A laminate comprising a release layer laminated on the surface of layer A of the film according to any one of (1) to (18).

ADVANTAGEOUS EFFECTS OF INVENTION

Films of the invention have a 60 ° gloss (G)₆₀) 85 ℃ gloss (G)₈₅) Are all as low as 27 or less, and the difference thereof is controlled within a specific range, and therefore is not dependent onSince the film exhibits an excellent low-gloss appearance at an incident angle, for example, when used as a transfer film, the film has excellent transferability of imparting a low-gloss appearance to a transfer object. Therefore, the transfer film can be suitably used as a transfer film having excellent transferability of matte appearance in a circuit forming process. Further, the present invention can be suitably used for decorative applications of molded members such as building materials, automobile parts, electronic products such as smart phones, and home electric appliances, and for transfer applications of surface shapes for imparting functionalities such as slidability, air-releasing properties, and light diffusion properties to functional layers.

Drawings

Fig. 1 is a schematic diagram showing a loose height solution.

Detailed Description

The films of the present invention are 60 ° gloss (G)₆₀) And 85 DEG gloss (G)₈₅) The low gloss layer (layer a) films each having a gloss of 27 or less are films in which the layer a is located on at least one surface layer. The above 60 ℃ gloss (G) from the viewpoint of low gloss appearance₆₀) 85 ℃ gloss (G)₈₅) Preferably all are 10 or less, most preferably all are less than 6. The resin used for the low-gloss layer is not particularly limited, and for example, polyesters such as polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate, polyarylate, polyethylene, polypropylene, polyamide, polyimide, polymethylpentene, polyvinyl chloride, polystyrene, polymethyl methacrylate, polycarbonate, polyether ether ketone, polysulfone, polyether sulfone, fluorine resin, polyether imide, polyphenylene sulfide, polyurethane, and cyclic olefin resins can be used. Among them, polyester is preferably used as the main component from the viewpoints of the operability of the film, the dimensional stability, and the economy in production. In the present invention, the main component means that the main component is contained in an amount of 50 mass% or more based on the whole layer.

The polyester in the present invention is a general term for polymers having an ester bond as a main bond in the main chain, and can be obtained by polycondensation reaction of a dicarboxylic acid component and a diol component.

Examples of the dicarboxylic acid component used herein include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, phthalic acid, 2, 6-naphthalenedicarboxylic acid, biphenyldicarboxylic acid, diphenylsulfonedicarboxylic acid, diphenoxyethanedicarboxylic acid, and sodium 5-sulfodicarboxylate (5- ナトリウムスルホンジカルボン acid), aliphatic dicarboxylic acids such as oxalic acid, succinic acid, adipic acid, sebacic acid, dimer acid, maleic acid, and fumaric acid, alicyclic dicarboxylic acids such as 1, 4-cyclohexanedicarboxylic acid, and hydroxycarboxylic acids such as p-hydroxybenzoic acid. Examples of the dicarboxylic acid ester derivative component include the esters of the dicarboxylic acid compounds described above, such as dimethyl terephthalate, diethyl terephthalate, 2-hydroxyethyl methyl terephthalate, dimethyl 2, 6-naphthalenedicarboxylate, dimethyl isophthalate, dimethyl adipate, diethyl maleate, and dimethyl dimer acid. In the polyester resin constituting the resin film of the present invention, the proportion of terephthalic acid and/or naphthalenedicarboxylic acid in the total dicarboxylic acid components is preferably 85 mol% or more, more preferably 90 mol% or more, which is preferable from the viewpoint of heat resistance and productivity.

Examples of the diol component include ethylene glycol, 1, 2-propanediol, 1, 3-butanediol, 1, 4-butanediol, 1, 5-pentanediol, 1, 6-hexanediol, 2-dimethyl-1, 3-propanediol, diethylene glycol, polyethylene glycol, polypropylene glycol, polybutylene glycol, 1, 4-cyclohexanedimethanol, spiroglycol, neopentyl glycol, bisphenol a, and bisphenol S. Among them, ethylene glycol, 1, 4-butanediol, 1, 3-propanediol, 1, 4-cyclohexanedimethanol, neopentyl glycol, and diethylene glycol are preferably used from the viewpoint of handling properties. In the polyester resin constituting the resin film of the present invention, it is preferable from the viewpoint of heat resistance and productivity if the proportion of ethylene glycol in the total glycol component is 65 mol% or more. These two carboxylic acid component, glycol component can be used in combination with 2 or more.

The film of the present invention is preferably a film having a base material layer on one side of the layer a. A film structure having a base layer on the a layer side is preferable because it is easy to combine strength and low gloss. The film of the invention preferably uses layer A/substrate layer 2A layer structure, a 3-layer structure of a layer a/a base material layer/a layer, and the like. In the present invention, when the A layers are disposed on both surface layers, the gloss (G) at 60 DEG is adjusted₆₀) The lower side was a1 layer, giving a 60 ℃ gloss (G)₆₀) The higher side is provided with a2 layer.

In the case of the film of the present invention having a base layer on one side of the a layer, as the resin constituting the base layer, for example, polyester such as polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyarylate, polyethylene, polypropylene, polyamide, polyimide, polymethylpentene, polyvinyl chloride, polystyrene, polymethyl methacrylate, polycarbonate, polyether ether ketone, polysulfone, polyether sulfone, fluororesin, polyetherimide, polyphenylene sulfide, polyurethane, cyclic olefin resin, and the like can be used, similarly to the resin used for the low-gloss layer (a layer). Among them, polyester is preferably used as the main component from the viewpoints of the operability of the film, the dimensional stability, and the economy in production.

The film of the present invention preferably has a thickness of the layer A of more than 3 μm and 20 μm or less. By making the thickness of the a layer thicker than 3 μm, the number of particles in the a layer becomes sufficiently large, and it is easy to control both the 60 ° gloss and the 85 ° gloss to be as low as 20 or less. Even if the thickness of the a layer is made larger than 20 μm, the influence on the glossiness is small, and on the other hand, the productivity may be lowered because the number of particles is too large. Therefore, the thickness of the a layer is preferably 20 μm or less. The thickness of the A layer is more preferably from 3.5 μm to 15 μm, and most preferably from 4 μm to 10 μm.

In the film of the present invention, the low gloss layer (a layer) preferably contains particles. As the particles contained in the a layer, both inorganic particles and organic particles can be used, and inorganic particles and organic particles can be used in combination. Here, the inorganic particles and/or organic particles used are not particularly limited, and for example, silica, aluminum silicate, calcium carbonate, calcium phosphate, alumina, and the like can be used as the inorganic particles, and particles containing styrene, silicone, acrylic, methacrylic, polyester, divinyl compound, and the like as a constituent component can be used as the organic particles. Among them, inorganic particles such as wet and dry silica, colloidal silica, and aluminum silicate, and particles containing styrene, silicone, acrylic acid, methacrylic acid, polyester, and divinylbenzene as a component are preferably used. Silica and aluminum silicate are particularly preferably used from the viewpoint of low gloss appearance and economy. In addition, two or more of these externally added particles may be used in combination.

In the present invention, the inorganic particles and the organic particles used do not contain a colorant for coloring purposes such as a dye, an inorganic pigment, and an organic pigment. Specifically, organic pigments such as iron oxide red, molybdenum red, cadmium red, chrome orange (chrome orange), chrome vermilion (molybdenum orange), ultramarine, navy, cobalt blue, blue (cerulean blue), etc., inorganic pigments such as chromium oxide, chromium green, emerald green, cobalt green, chrome yellow, cadmium yellow, iron oxide yellow, titanium yellow, manganese violet, mineral violet, titanium dioxide, barium sulfate, zinc oxide, zinc sulfate, carbon black, iron oxide black, etc., condensed azo, phthalocyanine, quinacridone, diazine, isoindolinone, phthalone (quinophthalone), anthraquinone-based, etc., do not correspond to the inorganic particles and organic particles of the present invention.

In the present invention, the gloss (G) is adjusted to 60 DEG on the surface of the low gloss layer (layer A)₆₀) And 85 DEG gloss (G)₈₅) In the above-mentioned a layer, the total amount of particles having an average particle diameter of 1.5 μm or more and 15 μm or less is preferably more than 18 mass% and 40 mass% or less, assuming that the layer a is 100 mass% as a whole. From the viewpoint of low gloss surface, the average particle diameter of the particles in the a layer is more preferably 3 μm or more and 15 μm or less, and most preferably 6 μm or more and 15 μm or less. The particle concentration in the a layer is set to 100% by mass in the whole a layer, and is more preferably 18% by mass or more and 40% by mass or less, and most preferably more than 22% by mass and 40% by mass or less. The average particle diameter in the present invention means a number average diameter D represented by Σ Di/N (Di: equivalent circle diameter of particles, N: number of particles).

In addition, the method can be used for producing a composite materialIn the present invention, the above-mentioned 60 ° gloss (G) is required in order to realize a low gloss surface independent of angle₆₀) And the above 85 DEG gloss (G)₈₅) Satisfies the following formula (I).

0.1≤(G₈₅)/(G₆₀)≤3···(I)

Satisfies the formula (I) and shows a 60 DEG gloss (G)₆₀) And 85 DEG gloss (G)₈₅) The difference in (b) is controlled to be small in a specific range, and a uniform low-gloss surface independent of the observation angle is obtained. From the viewpoint of uniform low-gloss surface, it is more preferable if the formula (II) is satisfied, and most preferable if the formula (III) is satisfied.

0.1≤(G₈₅)/(G₆₀)≤2···(II)

0.1≤(G₈₅)/(G₆₀)≤1.5···(III)。

In the present invention, the gloss (G) at 60 ℃ of the low gloss layer (layer A) is used₆₀) And 85 ° gloss (G)₈₅) All of them are 27 or less, and the method of satisfying the above formula (I) is not particularly limited, and examples thereof include a method of using particles having a polyhedral shape as the particles to be used, a method of using monodisperse particles, and a method of using polyhedral and monodisperse particles. By using particles having a polyhedral shape and/or monodisperse particles, it is possible to impart an uneven shape to the film surface and easily achieve low gloss in all directions. The polyhedral shape in the present invention means a three-dimensional shape surrounded by a plurality of planes. The number of planes is not particularly limited as long as it is three or more, and is more preferably tetrahedral or more, and most preferably tetrahedral or more and octahedral or less, from the viewpoint of imparting a non-uniform shape to the film surface. The polyhedron shape in the present invention may be any shape in which the surface is formed by various polygons such as a triangle, a quadrangle, and a pentagon. In the film of the present invention, the circularity (4. pi. times. area/perimeter) of the projected image obtained by the measurement method described later of the particles contained in the low gloss layer (layer A)²) Preferably 0.995 or less. More preferably 0.990 or less. On the other hand, if the circularity is too low, the hair is wornWhen the film is an oriented film, the direction of the particles may be uniform in the stretching direction, and a shape with little direction dependence is not easily formed on the film surface, and therefore the circularity is preferably 0.800 or more. In the film of the present invention, the bulk height of the particles contained in the low gloss layer (a layer) as determined by a measurement method described later is preferably 0.5 or more. When the film of the present invention is an oriented film, the film is formed through a step of stretching the film. In this case, in the case of particles having a small bulk (needle-like particles, plate-like particles), the direction of the particles is aligned in the stretching direction, and a shape having little direction dependency is not easily formed on the film surface. By containing the particles having large bulk in the low gloss layer (a layer), it becomes easy to impart a shape with little direction dependency to the film surface even in a film formed through a stretching step. The bulk height is more preferably 0.6 or more, and still more preferably 0.7 or more. On the other hand, the bulk height is preferably 0.9 or less from the viewpoint of achieving low gloss without angle dependence by providing the film surface with an uneven shape. The term "monodisperse particles" as used herein means particles having substantially no secondary aggregated particles, and the term "particles having primary particles dispersed in a polymer" means particles of 0.01mm per 0.01mm when the film is observed by a transmission electron microscope²The number of secondary aggregated particles in the field of view of (2) is 20 or less.

In the present invention, in order to form a low gloss surface independent of angle and to achieve both matte light transferability and film strength, a configuration is highly preferred in which the entire a layer is 100 mass% and contains particles having an average particle diameter of 6 μm to 15 μm in a polyhedron shape of 22 mass% to 40 mass% in a layer a having a thickness of 4 μm to 10 μm.

From the viewpoint of improving the film strength, the number of MIT bend fractures in at least one of the longitudinal direction (MD) and the width direction (TD) of the film of the present invention is preferably 7500 or more. By setting the MIT bend fracture number to 7500 or more, the occurrence of cracking or splitting at the time of peeling the film after transfer can be suppressed. It is more preferable that the MIT bending times be 7500 times or more in both the longitudinal direction (MD) and the width direction (TD). The method of setting the number of MIT bend failures in at least one of the longitudinal direction (MD) and the width direction (TD) to 7500 or more is not particularly limited, and for example, in the case of a biaxially stretched polyester film, it is preferable to use a method of stretching at a temperature equal to or higher than the crystallization temperature (Tcc) of the a layer before the heat treatment. By applying such conditions, fine oriented crystals are formed before the heat treatment and grown by the heat treatment, and thus, flakes which are considered as starting points of film cracking and splitting can be reduced.

From the viewpoint of improving the quality in high-temperature processing such as hot pressing, the film of the present invention preferably has a thermal dimensional change rate of 0.015%/° c or less in both the longitudinal direction (MD) and the width direction (TD) in the range of 100 to 150 ℃. By setting the thermal dimensional change rate to 0.015%/° c or less in the above direction, the occurrence of wrinkles due to expansion deformation during high-temperature processing can be suppressed. The thermal dimensional change rate is more preferably 0.012%/DEG C or less, and most preferably 0.009%/DEG C or less. In the present invention, the method of setting the thermal dimensional change rate in the range of 100 to 150 ℃ in the longitudinal direction (MD) and the width direction (TD) to 0.015%/° c or less is not particularly limited, and for example, in the case of a biaxially stretched polyester film, it is preferable to use a method of lowering the temperature stepwise after the heat treatment and relaxing the film in each step.

In the film of the present invention, the center line average roughness SRa of the surface of the a layer is preferably more than 1000nm and 3000nm or less from the viewpoint of matte appearance transferability. When the center line average roughness SRa on the a layer side is 1000nm or less, the matte tone transferability may be insufficient, and when it is made larger than 3000nm, the strength of the film may be reduced. From the viewpoint of matte transfer properties and film strength, the center line average roughness SRa on the a layer side is more preferably 1100nm or more and 2500nm or less, and most preferably 1200nm or more and 2000nm or less. In the present invention, the method of making the center line average roughness SRa of the a layer side to exceed 1000nm and be 3000nm or less is not particularly limited, and a method of adjusting the content of particles in the a layer and a method of reducing voids around the particles contained in the a layer are preferable. By reducing the voids around the particles, the shape of the particles is easily formed on the surface, and the center line average roughness SRa is easily controlled to be more than 1000nm and 3000nm or less. As a method for reducing the voids around the particles in the a layer, for example, in the case where the base layer and the low-gloss layer (a layer) are both formed of polyester and a biaxially stretched polyester film is used, it is preferable to use a method of improving the stretchability of the low-gloss layer (a layer), a method of reducing the voids by performing a treatment at a high temperature in a heat treatment step after stretching described later, or the like. In order to improve stretchability, the low-gloss layer (a layer) preferably contains a copolymerized polyethylene terephthalate resin, a polytrimethylene terephthalate resin and/or a copolymer thereof, and a polybutylene terephthalate resin and/or a copolymer thereof.

From the viewpoint of dimensional stability of the film, the film of the present invention preferably has a heat shrinkage rate at 150 ℃ of 2% or less in both the longitudinal direction (MD) and the width direction (TD). By controlling the heat shrinkage rate at 150 ℃ in the longitudinal direction (MD) and the width direction (TD) to be as low as 2% or less, the occurrence of curling, wrinkles, and the like in various processing steps can be suppressed. In the present invention, in order to further improve the dimensional stability, the heat shrinkage rate at 150 ℃ in the longitudinal direction (MD) and the width direction (TD) is more preferably 1.8% or less, and most preferably 1.5% or less.

From the viewpoint of handling properties, the film of the present invention preferably has a curl height of 0mm to 30mm after heat treatment at 150 ℃ for 10 minutes. In the present invention, the curl height after the heat treatment at 150 ℃ for 10 minutes is obtained by cutting a film into pieces having a length of 100mm in any one direction and a length of 100mm in a direction orthogonal to the direction, placing the pieces as samples in a hot air circulation type oven at 150 ℃ for 10 minutes to heat-treat the samples, placing the samples on a glass plate, measuring the amount of floating from the surface of the glass plate at four corners in the vertical direction, and calculating the maximum height as the curl height. The curl height is more preferable if it is 0mm or more and 25mm or less, and most preferable if it is 0mm or more and 20mm or less.

In the present invention, the method of setting the heat shrinkage rate at 150 ℃ in the longitudinal direction (MD) and the width direction (TD) to 2% or less and the method of setting the curl height after heat treatment at 150 ℃ for 10 minutes to 0mm or more and 30mm or less are not particularly limited, and examples thereof include a method of adjusting the heat treatment conditions of the film after biaxial stretching. When the treatment temperature is high, orientation relaxation tends to occur and the heat shrinkage rate tends to be reduced, but from the viewpoint of dimensional stability and film quality, the heat treatment temperature after biaxial stretching is preferably 220 to 240 ℃. The heat treatment temperature of the film can be determined from a minute endothermic peak due to a thermal history in a Differential Scanning Calorimeter (DSC) curve when measured at a temperature rise rate of 20 ℃/min under a nitrogen atmosphere, and in the film of the present invention, the minute endothermic peak temperature is preferably 220 to 240 ℃.

The preferable heat treatment time may be set arbitrarily to 5 to 60 seconds, but is preferably 10 to 40 seconds, and more preferably 15 to 30 seconds, from the viewpoint of dimensional stability, film quality, and productivity. Further, the heat shrinkage can be reduced by performing heat treatment while relaxing in the longitudinal direction and/or the width direction. The relaxation rate (relaxation rate) when relaxation is performed during heat treatment is preferably 1% or more, and from the viewpoint of dimensional stability and productivity, it is preferably 1% or more and 10% or less, and most preferably 1% or more and 5% or less.

Further, a method of performing heat treatment under 2 stages or more is also very preferable. The heat shrinkage can be further reduced by heat treatment at a high temperature of 220 to 240 ℃ and then heat treatment at a temperature lower than the heat treatment temperature while relaxing in the longitudinal direction and/or the width direction. The heat treatment temperature in the 2 nd stage in this case is preferably 120 ℃ or higher and less than 200 ℃, and more preferably 150 ℃ to 180 ℃. In addition, as a method for setting the curl height after the heat treatment at 150 ℃ for 10 minutes to 0mm or more and 30mm or less, for example, a method of providing a cooling roll on the opposite surface side of the cooling drum surface is also preferably used in order not to cause a difference in the cooling rate of the resin on the opposite surface to the cooling drum surface at the time of extruding the resin. In the case where the film of the present invention is a film having the above-described a layer on at least one surface of the base material layer, the film preferably has a structure having a layers on both surfaces of the base material layer, and even in the case where the film has a layer on one surface of the base material layer, the resin of the base material layer and the resin of the a layer are preferably made to have a similar composition.

The film of the present invention preferably has a variation in tensile break strength of 20cm × 30cm of 20% or less. By reducing the variation in the tensile breaking strength, the handling properties of the film are improved, and the film can be prevented from breaking at a weak position during film conveyance or transfer peeling. The variation in tensile break strength of the film of the present invention in the range of 20cm × 30cm was calculated as follows: the film was cut at an arbitrary position into samples having a width of 20cm × a length of 30cm, which were equally divided into 15cm along the longitudinal direction 2, and the samples having a length of 15cm were each cut into 1cm along the width direction, and the breaking strength was measured by a tensile test with respect to 40 long samples having a length of 15cm × a width of 1 cm. The variation in tensile break strength of the film in the range of 20cm × 30cm is more preferably 15% or less, and most preferably 0.1% or more and 10% or less.

As a method for making the variation of tensile break strength of the film of the present invention in the range of 20cm × 30cm to 20% or less, for example, a method for improving the dispersibility of particles contained in the a layer is exemplified. By improving the dispersibility of the particles, the particles are uniformly present in the a layer, and variation in tensile breaking strength can be reduced. The method of improving the dispersibility of the particles is not particularly limited, and examples thereof include a method of compounding the particles into a resin having high compatibility with the base resin constituting the a layer, and melt-extruding the raw material for the particle composite into the base resin to form the a layer. For example, when the base resin is polyethylene terephthalate, polybutylene terephthalate, polytrimethylene terephthalate, or the like is preferably selected as the resin for composite.

In view of transferability, the surface free energy of the surface of the A layer of the film of the present invention is preferably 44mN/m or less. Since the surface free energy is 44mN/m or less, the releasability from the transfer material is improved, and therefore, the transfer and the releasability are facilitated, and the transferability is improved. The surface free energy on the A layer side is more preferably 40mN/m or less, and most preferably 35mN/m or less. On the other hand, from the viewpoint of uniform coating properties of the transfer material and adhesiveness during processing, it is preferably 20mN/m or more.

The method of setting the surface free energy of the present invention to the above range is not particularly limited, and examples thereof include a method of including a release agent such as an organosilicon compound, a wax compound, or a fluorine-based compound in the a layer.

In the present invention, from the viewpoint of heat resistance during heating, it is preferable that the layer a be a layer containing a melamine resin and a release agent (hereinafter, the layer containing the release agent may be referred to as a release layer). The content of the melamine resin in the a layer is preferably 50 mass% or more from the viewpoint of heat resistance and mold release stability.

The melamine resin includes melamine formaldehyde resins such as melamine formaldehyde resin, methylated melamine formaldehyde resin, butylated melamine formaldehyde resin, etherified melamine formaldehyde resin, epoxy-modified melamine formaldehyde resin, urea melamine resin, acrylic melamine resin, etc., melamine formaldehyde resin is preferable, and methylated melamine formaldehyde resin is particularly preferable from the viewpoint of having appropriate releasability. In addition, from the viewpoint of film-forming properties and stretch-following properties, the layer a of the present invention preferably contains a binder resin in addition to the binder resin and the release agent. As the binder resin, polyester-based resins, acrylic-based resins, and urethane-based resins are preferably used, and acrylic-based resins are particularly preferably used. Examples of the acrylic resin include homopolymers or copolymers of alkyl (meth) acrylates and (meth) acrylate copolymers having a curable functional group at a side chain and/or a main chain end, and examples of the curable functional group include a hydroxyl group, a carboxyl group, an epoxy group, and an amino group. Among them, preferred is an acrylic monomer copolymer obtained by copolymerizing an acrylic monomer with an acrylate having a curable functional group at a side chain and/or a main chain end. Further, examples of the release agent contained in the layer a of the present invention include fluorine compounds, long-chain alkyl compounds, wax compounds, and the like. These releasing agents may be used alone or in combination of two or more.

The fluorine compound that can be used in the present invention is a compound containing a fluorine atom in the compound. Examples thereof include compounds having a perfluoroalkyl group, polymers of olefin compounds having a fluorine atom, and aromatic fluorine compounds such as fluorobenzene. When the release film of the present invention is used for the simultaneous transfer foil molding application or the like, a high thermal load is applied during transfer, and therefore, the fluorine compound is preferably a polymer compound in consideration of heat resistance and staining properties.

The long-chain alkyl compound is a compound having a linear or branched alkyl group having 6 or more carbon atoms, particularly preferably 8 or more carbon atoms. Specific examples thereof are not particularly limited, and examples thereof include a long-chain alkyl group-containing polyvinyl resin, a long-chain alkyl group-containing acrylic resin, a long-chain alkyl group-containing polyester resin, a long-chain alkyl group-containing amine compound, a long-chain alkyl group-containing ether compound, a long-chain alkyl group-containing quaternary ammonium salt, and the like. It is preferable that the long-chain alkyl compound is a polymer compound because the transfer of the component derived from the layer A to the surface of the substrate to be bonded can be suppressed when the release film is peeled.

The wax that can be used in the present invention is selected from natural waxes, synthetic waxes, and waxes containing these waxes. The natural wax includes vegetable wax, animal wax, mineral wax, and petroleum wax. Examples of the vegetable wax include candelilla wax, carnauba wax, rice wax, wood wax, and jojoba oil. Examples of the animal-based wax include beeswax, lanolin, and spermaceti wax. Examples of mineral waxes include montan wax, ozokerite (ozokerite), and Ceresin (Ceresin). Examples of the petroleum wax include Paraffin wax (Paraffin wax), microcrystalline wax, and petrolatum. Examples of the synthetic wax include synthetic hydrocarbons, modified waxes, hydrogenated waxes, fatty acids, acid amides, amines, imides, esters, and ketones. As synthetic hydrocarbons, fischer-tropsch wax (also called サゾワールワックス) and polyethylene wax are known, but in addition to these, the following polymers are also included as low molecular weight polymers (specifically, polymers having a viscosity average molecular weight of 500 to 20000). That is, there are polypropylene, ethylene/acrylic acid copolymers, polyethylene glycol, polypropylene glycol, and block or graft combinations of polyethylene glycol and polypropylene glycol. Examples of the modified wax include montan wax derivatives, paraffin wax derivatives, and microcrystalline wax derivatives. The derivative herein refers to a compound obtained by any one of purification, oxidation, esterification, and saponification, or a combination thereof. Hydrogenated castor oil and hydrogenated castor oil derivatives are examples of hydrogenated waxes.

By uniformly dispersing these release agents on the surface of the a layer, the adhesion force and the peeling force with the release receiving layer laminated on and peeled from the a layer can be set within an appropriate range. When a long-chain alkyl compound is used as the release agent, the release force can be adjusted in a wide range, and it is preferable in the use of the present invention.

Next, examples of specific methods for producing the film of the present invention will be described, but the present invention is not limited to these examples and will be explained.

When the film of the present invention is composed of a base layer and a low-gloss layer (a layer), and each layer is made of a polyester resin, the resins are supplied to respective extruders and melt-extruded. In this case, the resin temperature is preferably controlled to 255 ℃ to 295 ℃. Then, the mixture was passed through a filter and a gear pump to remove foreign matters and uniformize the extrusion amount, and the resulting laminate was coextruded from a T-die sheet onto a cooling drum to obtain a laminate sheet. At this time, the sheet-like polymer is brought into close contact with the casting drum and cooled and solidified by an electrostatic application method in which a high voltage is applied to the electrode to electrostatically bring the cooling drum into close contact with the resin, a casting method in which a water film is provided between the casting drum and the extruded polymer sheet, a method in which the extruded polymer is brought into close contact with the casting drum at a temperature of from the glass transition temperature of the polyester resin to (the glass transition temperature of-20 ℃), or a combination of a plurality of these methods. Among these casting methods, when polyester is used, a method of applying static electricity is preferable from the viewpoint of productivity and flatness, and a method of providing a cooling roll on the side opposite to the cooling drum is also preferable from the viewpoint of suppressing curling at the time of heating. The film of the present invention is preferably a biaxially oriented film from the viewpoint of heat resistance and dimensional stability. The biaxially oriented film can be obtained as follows: the stretching is performed by a sequential biaxial stretching method in which an unstretched film is stretched in the longitudinal direction and then in the width direction, or stretched in the longitudinal direction after being stretched in the width direction, or a simultaneous biaxial stretching method in which the film is stretched in the longitudinal direction and the width direction almost simultaneously, or the like.

The stretching magnification in such a stretching method is 2.8 times or more and 3.4 times or less, and more preferably 2.9 times or more and 3.3 times or less in the longitudinal direction. Further, the stretching speed is desirably 1,000%/minute or more and 200,000%/minute or less. The stretching temperature in the longitudinal direction is preferably 70 ℃ to 90 ℃. The stretching ratio in the width direction is preferably 2.8 times or more and 3.8 times or less, and more preferably 3 times or more and 3.6 times or less. The stretching speed in the width direction is desirably 1,000%/minute or more and 200,000%/minute or less. The stretching temperature in the width direction is preferably 70 ℃ to 180 ℃, but is more preferably a temperature equal to or higher than the crystallization temperature of the a layer from the viewpoint of improving the film strength. Further, heat treatment of the film is performed after biaxial stretching. The heat treatment may be carried out by any conventionally known method such as in an oven or on a heated roll. The heat treatment is performed at a temperature of 120 ℃ or higher and not higher than the crystal melting peak temperature of the polyester, but a high temperature of 220 ℃ or higher is preferable from the viewpoint of reducing voids around the particles in the a layer and from the viewpoint of controlling the heat shrinkage rate at 150 ℃ to be as low as 2% or lower. From the viewpoint of making the thermal dimensional change rate in the range of 100 to 150 ℃ 0.015%/° c or less, it is preferable to perform the relaxation treatment while lowering the temperature stepwise after the heat treatment. More specifically, it is preferable to perform a relaxation heat treatment with a relaxation rate of 0.5% or more at the maximum temperature (Tmax) of the heat treatment, and then perform a relaxation heat treatment with a relaxation rate of 0.5% or more in 1 stage or more at a temperature of Tmax-50 ℃ or more and Tmax-5 ℃ or less. The relaxation heat treatment at Tmax-50 ℃ or higher and Tmax-5 ℃ or lower is preferably performed 1 or more times in each of temperature ranges of Tmax-25 ℃ or higher and Tmax-5 ℃ or lower and Tmax-50 ℃ or higher and less than Tmax-25. The relaxation heat treatment may be performed in either the longitudinal direction or the width direction, but in the case of biaxial stretching by sequential biaxial stretching, it is preferable from the viewpoint of productivity to perform the relaxation heat treatment continuously after stretching in the stretching direction with respect to the second axis.

Further, in order to ensure stable releasability, it is also preferable that the film of the present invention is a laminate in which a release layer is provided on the surface of the layer a of the film. The method of providing the release layer is not particularly limited, and an in-line coating (in-line coating) method may be mentioned. As a method for providing the coating layer on-line in the film production process, a method of uniformly applying a substance in which the coating layer composition is dispersed in water to a film subjected to at least uniaxial stretching using a metal bar, a gravure roll or the like and drying the coating agent while stretching is preferably used, and in this case, the thickness of the release layer is preferably 0.02 μm or more and 0.1 μm or less. In addition, various additives such as an antioxidant, a heat stabilizer, an ultraviolet absorber, an infrared absorber, a pigment, a dye, organic or inorganic particles, an antistatic agent, a nucleating agent, and the like may be added to the release layer.

Films of the invention have a 60 ° gloss (G)₆₀) 85 ℃ gloss (G)₈₅) The low gloss appearance is excellent regardless of the incident angle, and the transferability of the low gloss appearance is excellent when the transfer film is used. Therefore, the transfer film can be suitably used as a transfer film having excellent transfer properties of matte appearance in a circuit forming process.

Examples

(1) Composition of polyester

The polyester resin and the film can be dissolved in Hexafluoroisopropanol (HFIP) and used¹H-NMR and¹³C-NMR was carried out to determine the content of the residue component of each monomer and diethylene glycol as a by-product. In the case of a laminated film, each layer of the film is cut out in accordance with the thickness of the laminate, and the components constituting each individual layer are taken out and evaluated. In addition, the composition of the film of the present invention was calculated from the mixing ratio at the time of film production.

(2) Intrinsic viscosity of polyester

The polyester was dissolved in o-chlorophenol, and the intrinsic viscosity of the polyester resin and the film was measured at 25 ℃ using an Ostwald viscometer. In the case of a laminated film, each layer of the film may be cut out according to the thickness of the laminate to evaluate the intrinsic viscosity of each individual layer.

(3) Film thickness

The film thickness was measured using a direct-reading thickness meter.

(4) Thickness of each layer

The film was embedded in epoxy resin, and the film section was cut with a microtome. The cross section was observed with a transmission electron microscope (TEM H7100, hitachi) at a magnification of 5000 times, and the thickness of each layer was determined.

(5) Average particle diameter of particles

The resin was removed from the film by a plasma low-temperature ashing treatment (model PR-503, manufactured by ヤマト science) to expose the particles. The particles were observed with a transmission electron microscope (TEMH 7100, hitachi), an image of the particles (the intensity of light formed by the particles) was connected to an image analyzer (QTM 900, ケンブリッジインストルメント), the observed position was changed, the number average diameter D obtained by the numerical processing below was calculated as the average particle diameter by the number of 100 particles.

D＝ΣDi/N

Where Di is the equivalent circle diameter of the particles and N is the number of the particles.

(6) Shape/circularity of particles

The image of the particle was observed in the same manner as in (5). The circularity is calculated by the following equation, and the average value of 100 particles is defined as the circularity of the present invention.

Circularity 4 pi x area/perimeter²

(7) Shape/bulk of the particles

A section of the film parallel to the longitudinal direction of the film and perpendicular to the thickness direction of the film, and a section of the film parallel to the width direction of the film and perpendicular to the thickness direction of the film were cut with a microtome and observed by the method described in (5). In the cross-sectional particle, L1 represents the longest length between the ends of the particle, and L2 represents the longest length between the ends of the particle in the direction perpendicular to the line segment connecting the ends of the particle to the ends when the above-mentioned L1 is obtained (fig. 1). The bulk height was determined by averaging 100 pieces of L2/L1 in each of a film cross section parallel to the film length direction and perpendicular to the film thickness direction and a film cross section parallel to the film width direction and perpendicular to the film thickness direction.

(8) Content of particles

1g of the polymer was put into 200ml of a 1N-KOH methanol solution and heated under reflux to dissolve the polymer. 200ml of water was added to the solution after completion of the dissolution, and then the liquid was supplied to a centrifugal separator to settle the particles, and the supernatant was removed. Further water was added to the particles to wash them, and the centrifugal separation was repeated 2 times. The particles thus obtained were dried, and the mass thereof was measured to calculate the content of the particles.

(9) Degree of gloss

According to the method prescribed in JIS-Z-8741 (1997), 60 ° specular gloss and 85 ° specular gloss were measured as N ═ 3 respectively using スガ strain test digital variable angle gloss meter UGV-5D, and the average value was defined as 60 ° gloss (G) of the present invention₆₀) 85 ℃ gloss (G)₈₅)。

(10) Number of MIT bends

The polyester film was cut into a strip having a width of 15mm and a length of 100mm to obtain a sample. The length and width of the film were measured 3 times using an MIT folding resistance tester (manufactured by (Ltd.) マイズ) test, and the average value was calculated.

Front-end: r0.38mm

Bending angle: left and right 135 °

Bending speed: 175 round trips/minute

Load: 9.8N

(11) Center line average roughness SRa

The surface morphology of the film was measured under the following conditions using a high-precision fine shape measuring instrument (3-dimensional surface roughness meter) by a stylus method using a sample cut into a size of 4.0cm in length × 3.5cm in width according to JIS B0601-1994.

The measurement device: 3-D Fine shape measuring apparatus (ET-4000A type, manufactured by Okagaku K.K.)

The analytic device: 3D surface roughness analysis system (TDA-31 type)

The stylus: diamond with a radius of 0.5 μm R at the tip and a diameter of 2 μm

Needle pressure: 100 mu N

Measurement direction: the film length direction and the film width direction were measured 1 time each and averaged

X measurement length: 1.0mm

X feed speed: 0.1mm/s (measuring speed)

Y feed pitch: 5 μm (measurement gap)

Number of Y lines: 81 strips (number of strips)

Z magnification: 20 times (longitudinal multiplying power)

Low domain cutoff: 0.20mm

High domain cut-off: r + Wmm (roughness cutoff) indicates that R + W was not taken.

Filtration mode: gaussian spatial pattern

Leveling: is (inclination correction)

Reference area: 1mm²。

After the measurement under the above conditions, the center line average roughness SRa was calculated using an analytical system.

(12) Thermal dimensional change rate in the range of 100 ℃ to 150 ℃

A sample was obtained by cutting a rectangle having a length of 50mm × a width of 4mm so that the longitudinal direction (MD) and the width direction (TD) were the longitudinal direction, and the temperature was raised under the following conditions using a thermomechanical analyzer (manufactured by セイコ - インスツルメンツ, TMAEXSTAR6000), and the thermal dimensional change rate at 100 to 150 ℃.

Test length: 15mm, load: 19.6mN, temperature rising rate: the temperature of the mixture is 10 ℃/minute,

measurement temperature range: 30 to 200 DEG C

Thermal dimensional change ratio (%) in the range of 100 to 150 [ { membrane length (mm) at 150 ℃ -membrane length (mm) at 100 ℃) }/membrane length (mm) at 100 ℃) ] × 100

In addition, each film was evaluated as an average value by measuring 5 samples in the longitudinal direction and the width direction.

(13) Thermal shrinkage at 150 DEG C

A rectangle having a length of 150mm × a width of 10mm was cut out as a sample so that the longitudinal direction (MD) and the width direction (TD) were the longitudinal direction. The samples were marked at intervals of 100mm, suspended by a weight of 3g, and heated in a hot-air furnace heated to 150 ℃ for 30 minutes. The distance between the marks after the heat treatment was measured, and the heat shrinkage was calculated from the change in the distance between the marks before and after the heating by the following equation. Each film was evaluated as an average value by measuring 5 samples in the longitudinal direction and the width direction.

The heat shrinkage rate (%) { (distance between standard lines before heat treatment) - (distance between standard lines after heat treatment) }/(distance between standard lines before heat treatment) × 100.

(14) Crimp height after heat treatment at 150 ℃ for 10 minutes

The film was cut into a size of 100mm in length in any one direction and 100mm in length in a direction orthogonal to the direction, and the sample was obtained. The sample was left to stand in a hot air circulating oven at 150 ℃ for 10 minutes for heat treatment, and then placed on a glass plate, the amount of lifting from the surface of the glass plate at four corners in the vertical direction was measured, and the maximum height was defined as the curl height.

(15) Deviation of tensile breaking strength of film in 20cm x 30cm range

The film was cut at an arbitrary position into samples each having a width of 20cm × a length of 30cm, which were equally divided into 15cm along the longitudinal direction 2, and the samples each having a length of 15cm were cut into 1cm along the width direction, thereby preparing 40 long samples each having a length of 15cm × a width of 1 cm. For this sample, a tensile test was carried out using a tensile tester (テンシロン UCT-100, manufactured by オリエンテック) with an initial distance between tensile chucks of 50mm and a tensile speed of 300 mm/min, and the strength at the time of film breaking (tensile breaking strength) was measured to determine the variation as described below.

Deviation (%) of tensile break strength { (maximum-minimum)/average } × 100

(16) Surface free energy

As the measurement liquids, 4 kinds of water, ethylene glycol, formamide and diiodomethane were used, and the static contact angle of each liquid with respect to the film surface was obtained by using a contact angle meter (CA-D type manufactured by Kyowa interface science Co., Ltd.). The liquid was measured 5 times, the average contact angle (θ) and the surface tension of the measurement liquid (j) were substituted into the following equation, and γ was solved from a simultaneous equation consisting of 4 equations^L、γ⁺、γ^-。

(γ^Lγj^L)^1/2+2(γ⁺γj^-)^1/2+2(γj⁺γ^-)^1/2

＝(1+cosθ)[γj^L+2(γj⁺γj^-)^1/2]/2

Wherein γ ═ γ^L+2(γ⁺γ^-)^1/2

γj＝γj^L+2(γj⁺γj^-)^1/2

Here, γ^L、γ⁺、γ^-Respectively represent the surface free energy, long range force term, Lewis acid parameter, Lewis base parameter, and in addition, gamma j^L、γj⁺、γj^-Respectively, the surface free energy, the long-range force term, the Lewis acid parameter and the Lewis base parameter of the measurement liquid to be used. In addition, the surface tension of each liquid used herein uses a value proposed by Oss ("fundamental sof addition", l.h.lee (Ed.), p153, plenum, New York (1991)).

(17) Peelability of

The film was cut into a length of 100 mm. times.a width of 100mm and used. The following coating composition for forming a hard coat layer was applied using a slot die coater while controlling the flow rate so that the thickness after drying became 5 μm, and the coating composition was dried at 100 ℃ for 1 minute to remove the solvent, thereby obtaining a laminate having a hard coat layer laminated thereon.

The obtained film/hard coat layer laminate was heated to 160 ℃ using a press at both the upper and lower die temperatures, and the thickness was set to 0A composition of an aluminum plate of 2 mm/a polyimide film of 0.125mm in thickness (カプトン 500H/V manufactured by imperial レデュポン)/a laminate/a polyimide film of 0.125mm in thickness (カプトン 500H/V manufactured by imperial レデュポン)/an aluminum plate of 0.2mm in thickness was heated and pressed under a pressure of 1.5MPa for 1 hour. After heating and pressurizing, the laminate was taken out and irradiated with 300mJ/cm of light from the laminate side using a high pressure mercury lamp²The hard coat layer is cured to obtain a sample. The sample was subjected to a peeling test at the interface between the film and the hard coat layer, and the peeling property was evaluated by the following criteria. In addition, in the case where the film was provided with a release layer, a peeling test was performed at the film/release layer and hard coat layer interface. The peeling test was performed 5 times and evaluated by the following evaluation criteria.

(coating composition for hard coat layer formation)

The following materials were mixed and diluted with methyl ethyl ketone to obtain a coating composition for forming a hard coat layer having a solid content of 40 mass%.

(evaluation criteria)

A: it could be peeled off without resistance (in 5 peel tests, none) without film cracking.

B: resistance was felt at peeling, but peeling was enabled, and film breakage did not occur (in any of the 5 peeling tests).

C: peeling was possible, but (in 5 peeling tests, there were cases where film breakage occurred upon peeling.

D: (in 5 peel tests, none) could be peeled off.

(18) Crimpability after heating and pressing

The laminate heated and pressed in the same manner as in (17) was placed on a glass plate, and the amount of lifting from the glass plate surface at the four corners in the vertical direction was measured, and the maximum height was defined as the curl height.

A: the crimp height is more than 0mm and less than 10mm

B: the crimp height is more than 10mm and less than 20mm

C: the crimp height is more than 20mm and less than 30mm

D: the crimp height is 30mm or more.

(18) Transfer printing property of matte tone appearance, uniformity and beauty

The gloss on the release surface side of the hard coat layer obtained by the method of (17) was measured, and the average value thereof was evaluated by the following criteria.

(transfer printing of matte appearance)

A: 60 degree gloss (G)₆₀) And 85 DEG gloss (G)₈₅) Are all 10 or less

B: 60 degree gloss (G)₆₀) And 85 DEG gloss (G)₈₅) One of the two is 10 or less, and the other is more than 10 and 27 or less

C: 60 degree gloss (G)₆₀) And 85 DEG gloss (G)₈₅) Are all 10 to 27 inclusive

D: 60 degree gloss (G)₆₀) And 85 DEG gloss (G)₈₅) At least one of which is greater than 27.

(matte appearance uniform and beautiful)

A：0.1≤(G₈₅)/(G₆₀)≤1.5

B：1.5＜(G₈₅)/(G₆₀)≤2

C：2.0＜(G₈₅)/(G₆₀)≤3

D：0.1＞(G₈₅)/(G₆₀) Or (G)₈₅)/(G₆₀)＞3

(19) Quality of transfer printing

The hard coat layer obtained by the method (17) was visually observed on the release surface side and evaluated by the following criteria.

A: no wrinkles are seen

B: not conforming to A, the number of wrinkles produced was 2 or less

C: not conforming to A, B, resulting in less than 5 wrinkles

D: A. b, C are not met.

(production of polyester)

The polyester resin for film formation was prepared as follows.

(polyester A)

A polyethylene terephthalate resin (intrinsic viscosity 0.75) containing 100 mol% of a terephthalic acid component as a dicarboxylic acid component and 100 mol% of an ethylene glycol component as a glycol component.

(polyester B)

A copolymerized polyethylene terephthalate resin (intrinsic viscosity 0.8) obtained by copolymerizing 20 mol% of isophthalic acid with respect to the dicarboxylic acid component.

(polyester C)

A polybutylene terephthalate resin (intrinsic viscosity 1.2) containing 100 mol% of a terephthalic acid component as a dicarboxylic acid component and 100 mol% of a1, 4-butanediol component as a diol component.

(polyester D)

"ハイトレル (registered trademark)" 7247 manufactured by imperial レ - デュポン.

(particle masterbatch E)

A polyethylene terephthalate particle master batch (intrinsic viscosity 0.7) containing aluminum silicate particles having an average particle diameter of 6 μm/hexahedron shape in a particle concentration of 30 mass% in polyester A.

(particle masterbatch F)

A polyethylene terephthalate particle master batch (intrinsic viscosity 0.7) containing aluminum silicate particles having an average particle diameter of 7.5 μm/hexahedron shape in a particle concentration of 30 mass% in the polyester A.

(particle masterbatch G)

A polyethylene terephthalate particle master batch (intrinsic viscosity 0.7) containing aluminum silicate particles having an average particle diameter of 10 μm/hexahedron shape in a particle concentration of 30 mass% in polyester A.

(particle masterbatch H)

A polyethylene terephthalate particle master batch (intrinsic viscosity 0.7) containing aluminum silicate particles having an average particle diameter of 7.5 μm/octahedron shape in a particle concentration of 30 mass% in the polyester A.

(particle masterbatch I)

A polyethylene terephthalate particle master batch (intrinsic viscosity 0.7) containing aluminum silicate particles having an average particle diameter of 5 μm/spherical shape in a particle concentration of 30 mass% in the polyester A.

(particle masterbatch J)

A polyethylene terephthalate particle master batch (intrinsic viscosity 0.7) containing aluminum silicate particles having an average particle diameter of 7.5 μm/spherical shape in a particle concentration of 30 mass% in the polyester A.

(particle masterbatch K)

A polyethylene terephthalate particle master batch (intrinsic viscosity 0.7) containing aluminum silicate particles having an average particle diameter of 6 μm/hexahedron shape in a particle concentration of 30 mass% in polyester C.

(particle masterbatch L)

A polyethylene terephthalate particle master batch (intrinsic viscosity 0.7) containing aluminum silicate particles having an average particle diameter of 7.5 μm/hexahedron shape in a particle concentration of 30 mass% in polyester C.

(particle masterbatch M)

A polyethylene terephthalate particle master batch (intrinsic viscosity 0.7) containing aluminum silicate particles having an average particle diameter of 10 μm/hexahedron shape in a particle concentration of 30 mass% in polyester C.

(particle masterbatch N)

A polyethylene terephthalate particle master batch (intrinsic viscosity: 0.7) containing aluminum silicate particles having an average particle diameter of 7.5 μm/octahedron shape in a particle concentration of 30 mass% in polyester C.

(particle masterbatch O)

A polyethylene terephthalate particle master batch (intrinsic viscosity 0.7) containing aluminum silicate particles having an average particle diameter of 5 μm/spherical shape in a particle concentration of 30 mass% in the polyester C.

(particle masterbatch P)

A polyethylene terephthalate particle master batch (intrinsic viscosity: 0.7) containing aluminum silicate particles having an average particle diameter of 7.5 μm/spherical shape in a particle concentration of 30 mass% in the polyester C.

(particle masterbatch Q)

A polyethylene terephthalate particle master batch (intrinsic viscosity 0.7) containing alumina particles having an average particle diameter of 6 μm/average thickness of 0.10 μm in a particle concentration of 30 mass% in the polyester C.

(solution (aqueous dispersion) for Forming Release layer.)

Crosslinking agents shown below: binder resin: releasing agent: the mass ratio of the particles is 60: 23: 17, and was adjusted by diluting with pure water so that the solid content became 1% by mass.

Crosslinking agent: crosslinked resin obtained by copolymerization of methylated Melamine/Urea ((manufactured by shin san Kagaku Co., Ltd. "ニカラック" (registered trademark) "MW 12 LF")

Binder resin I: acrylic monomer copolymer (manufactured by Japanese カーバイド)

Mold release agent: in a glass reaction vessel, CF as an acrylate containing a perfluoroalkyl group is added₃(CF₂)_nCH₂CH₂OCOCH＝CH₂(n is 5 to 11, and the average of n is 9)80.0g, acetoacetoxyethyl methacrylate 20.0g, dodecylmercaptan 0.8g, deoxidized pure water 354.7g, acetone 40.0g, and C₁₆H₃₃N(CH₃)₃Cl 1.0g and C₈H₁₇C₆H₄O(CH₂CH₂O)_n3.0g of H (n ═ 8), 0.5g of azobisisobutylamidine dihydrochloride was added, and copolymerization was performed at 60 ℃ for 10 hours while stirring under a nitrogen atmosphere.

Particles: an aqueous dispersion was obtained by diluting silica particles having an average particle diameter of 170nm ("スノーテックス" (registered trademark) MP2040, manufactured by nippon chemical industry co., ltd.) with pure water so that the solid content concentration became 40 mass%.

(example 1)

The raw materials were fed to an extruder so that the composition and lamination ratio were as shown in the table, the barrel temperature of the extruder was 270 ℃, the short pipe temperature was 275 ℃, the die temperature was 280 ℃, and the raw materials were discharged from a T-die in a sheet-like manner at a resin temperature of 280 ℃ onto a cooling drum controlled to a temperature of 25 ℃. At this time, electrostatic application was performed using a wire electrode having a diameter of 0.1mm, and the resultant was closely adhered to a cooling drum, and a cooling roll having a temperature controlled to 25 ℃ was further provided on the side opposite to the cooling drum, thereby obtaining an unstretched sheet. Then, the film was stretched 3.1 times at a stretching temperature of 85 ℃ in the longitudinal direction, and then subjected to corona discharge treatment, and a solution for forming a mold release layer (aqueous dispersion) was applied using a metal rod so that the wet thickness became 13.5 μm, followed by stretching at a stretching ratio of 3.3 times at a stretching temperature of 100 ℃ in the width direction using a tenter type transverse stretcher. Then, in a tenter, heat treatment was performed at 235 ℃ for 15 seconds, followed by heat treatment at 175 ℃ for 10 seconds while performing 3.5% relaxation in the width direction, to obtain a film having a film thickness of 50 μm (the surface of the low gloss layer (a layer) was defined as a1 plane, and the surface of the substrate layer was defined as B plane).

(example 2)

A film having a film thickness of 50 μm was obtained in the same manner as in example 1 except that the composition was changed as shown in the table.

(example 3)

(example 4)

(example 5)

(example 6)

(example 7)

(example 8)

A film having a film thickness of 50 μm was obtained in the same manner as in example 2, except that the composition was stretched in the width direction as shown in the table, and then heat-treated for 30 seconds while performing 1% relaxation in the width direction at 225 ℃.

(example 9)

(example 10)

A film having a film thickness of 50 μm was obtained in the same manner as in example 4 except that, when the composition was extruded from the extruder sheet onto the cooling drum as shown in the table, an unstretched sheet was obtained without providing a cooling roll on the side opposite to the cooling drum, and the unstretched sheet was stretched in the longitudinal direction and then subjected to no corona discharge treatment or release layer coating.

(example 11)

A film having a film thickness of 50 μm was obtained in the same manner as in example 5, except that the composition was changed to a 3-layer composition of layer a/base layer/layer a as shown in the table.

(example 12)

(example 13)

A film having a film thickness of 38 μm was obtained in the same manner as in example 5, except that the composition was changed to a 3-layer composition of layer a/base layer/layer a as shown in the table.

(example 14)

(example 15)

(example 16)

A film having a film thickness of 50 μm was obtained in the same manner as in example 5, except that the corona discharge treatment and the release layer coating were not performed after the stretching in the longitudinal direction.

(example 17)

A film having a film thickness of 50 μm was obtained in the same manner as in example 1, except that the composition was changed as shown in the table and the transverse stretching temperature was set to 140 ℃.

(example 18)

(example 19)

A film having a film thickness of 50 μm was obtained in the same manner as in example 1, except that the composition was changed as shown in the table.

(example 20)

(example 21)

A film having a film thickness of 50 μm was obtained in the same manner as in example 1, except that the composition was changed as shown in the table, and after stretching in the width direction, relaxation heat treatment in the width direction was performed for 5 seconds under the conditions of 2.0% at 235 ℃ and 1.5% at 210 ℃.

(example 22)

A film having a film thickness of 50 μm was obtained in the same manner as in example 1 except that the composition was changed as shown in the table, and after stretching in the width direction, relaxation heat treatment in the width direction was performed for 5 seconds under the conditions of 1.5% at 235 ℃, 1.0% at 215 ℃ and 1.0% at 200 ℃.

(example 23)

A film having a film thickness of 50 μm was obtained in the same manner as in example 1, except that the composition was changed as shown in the table, and after stretching in the width direction, the relaxation heat treatment in the width direction was performed at 240 ℃ for 3.5% for 15 seconds.

(example 24)

(example 25)

Comparative example 1

Comparative example 2

Comparative example 3

Comparative example 4

Comparative example 5

Comparative example 6

A film having a film thickness of 50 μm was obtained in the same manner as in example 1, except that the composition was changed to 3.8 times the draw ratio in the width direction as shown in the table.

Comparative example 7

[ Table 1]

[ Table 2]

[ Table 3]

[ Table 4]

[ Table 5]

[ Table 6]

[ TABLE 7 ]

Industrial applicability

Films of the invention have a 60 ° gloss (G)₆₀) 85 ℃ gloss (G)₈₅) All of them are as low as 27 or less, and the difference is controlled to be small within a specific range, so that excellent low gloss appearance is exhibited regardless of the incident angle, and in the case of using as a transfer film, transferability of the low gloss appearance is excellent. Therefore, the transfer film can be suitably used as a transfer film having excellent transferability of matte appearance in a circuit forming process. Further, the present invention can be suitably used for decorative applications of molded members such as building materials, automobile parts, electronic products such as smart phones, and home electric appliances, and transfer applications of surface shapes for imparting functionalities such as slidability, air-releasing properties, and light diffusion properties to functional layers.

Claims

1. A film having a 60 DEG gloss G₆₀And 85 DEG gloss G₈₅A low gloss layer, i.e., a layer A, both of 27 or less, said layer A being located on at least one surface layer, said 60 DEG gloss G₆₀And the 85 DEG gloss G₈₅Satisfies the following formula (I),

0.1≤(G₈₅)/(G₆₀)≤3···(I)。

2. the film of claim 1, the low gloss layer being layer a having a 60 ° gloss G₆₀And 85 DEG gloss G₈₅Are all 10 or less.

3. The film according to claim 1 or 2, wherein the film has a variation in tensile break strength of 20cm x 30cm of 20% or less.

4. The film according to any one of claims 1 to 3, having a substrate layer on one side of the A layer.

5. The film according to claim 4, wherein the base layer and the layer A each contain a polyester resin as a main component.

6. The film according to any one of claims 1 to 5, wherein the thickness of the A layer exceeds 3 μm and is 20 μm or less.

7. The film according to any one of claims 1 to 6, wherein the A layer contains particles having an average particle diameter of 1.5 μm or more and 15 μm or less, the A layer as a whole being 100% by mass, and the content of the particles being more than 18% by mass and 40% by mass or less.

8. The film according to any one of claims 1 to 6, wherein the A layer contains particles having an average particle diameter of 3 μm or more and 15 μm or less, the A layer as a whole being 100% by mass, and the content of the particles being 18% by mass or more and 40% by mass or less.

9. The film of claim 7 or 8, the particles having a circularity of 0.995 or less.

10. The film of claim 7 or 8, the particles having a circularity of 0.995 or less and a bulk height of 0.5 or more.

11. The film according to any one of claims 1 to 10 having a 60 ° gloss G₆₀Less than 6.

12. The film according to any one of claims 1 to 11, wherein the number of MIT bending fractures in at least one of the longitudinal direction MD and the width direction TD is 7500 or more.

13. The film according to any one of claims 1 to 12, wherein the thermal dimensional change rates in the longitudinal direction MD and the width direction TD are 0.015%/° c or less in the ranges of 100 ℃ to 150 ℃.

14. The film according to any one of claims 1 to 13, wherein the surface of the a layer has a center line average roughness SRa of more than 1000nm and 3000nm or less.

15. The film according to any one of claims 1 to 14, wherein the heat shrinkage rates at 150 ℃ in both the longitudinal direction MD and the width direction TD are 2% or less.

16. The film according to any one of claims 1 to 15, having a curl height after heat treatment at 150 ℃ for 10 minutes of 0mm or more and 30mm or less as measured by the following method,

the determination method comprises the following steps: the film was cut into a size of 100mm in length in any one direction and 100mm in length in a direction orthogonal to the direction, as a sample; the sample was left to stand in a hot air circulating oven at 150 ℃ for 10 minutes for heat treatment, and then placed on a glass plate, the amount of lifting from the surface of the glass plate at four corners in the vertical direction was measured, and the maximum height was defined as the curl height.

17. The film according to any one of claims 1 to 16, wherein the surface free energy of the surface of the layer a is 44mN/m or less.

18. The film according to any one of claims 1 to 17, which is used for transfer application.

19. A laminate comprising a release layer laminated on the surface of layer A of the film according to any one of claims 1 to 18.