CN110154462B

CN110154462B - Magnetic pigment flake

Info

Publication number: CN110154462B
Application number: CN201910464844.4A
Authority: CN
Inventors: 牛亮亮; 石斌; 向杰; 徐明权; 刘佳辉
Original assignee: Huizhou Foryou Optical Technology Co ltd
Current assignee: Huizhou Foryou Optical Technology Co ltd
Priority date: 2019-05-30
Filing date: 2019-05-30
Publication date: 2021-12-28
Anticipated expiration: 2039-05-30
Also published as: CN110154462A

Abstract

The application provides a magnetic pigment flake, which comprises a magnetic reflection layer, and a first dielectric layer and a first absorption layer which are sequentially stacked and arranged on a first main surface of the magnetic reflection layer, wherein the magnetic reflection layer comprises at least one alloy containing a magnetic material. Through this kind of mode, the magnetic pigment piece of this application adopts magnetic reflection layer to replace traditional magnetic layer and reflection stratum, and magnetic strength is great, has improved the cohesion between magnetic layer and the reflection stratum, has reduced the layering phenomenon, simultaneously, because the structure of this magnetic pigment piece is simpler, has reduced manufacturing cost, and has improved the apparent color saturation of this magnetic pigment piece.

Description

Magnetic pigment flake

Technical Field

The present application relates to the field of magnetic pigment flakes, and more particularly to magnetic pigment flakes.

Background

Optically variable pigment flakes are meant to exhibit different colors when viewed from different angles by an observer using the principle of optical interference between multiple thin films. The said property is printed on the substrate as pigment and can not be copied and scanned by copier scanner, so that it is very suitable for making anti-fake label of currency, securities and invoice. In addition to security applications, optically variable pigments can also be used as decorative pigments.

With the advent of various counterfeit means, the requirements for anti-counterfeit technology are increasing. The magnetic optically variable pigment is produced at the same time. The magnetic optically variable pigment is characterized in that a magnetic material is added into the structure of the common optically variable pigment to ensure that the optically variable pigment has magnetic characteristics. The magnetic optically variable pigment commonly used at present has the following problems: high production cost, insufficient color or brightness of the optically variable pigment, limited regulation and control of the magnetic strength of the magnetic material and easy delamination of the magnetic layer and the dielectric layer, thereby influencing the product performance.

Disclosure of Invention

The application provides a magnetic pigment flake, which aims to solve the problems that the color and luster or the brightness of the magnetic pigment flake are insufficient, a magnetic layer and a dielectric layer are easy to layer and the production cost is high in the prior art.

In order to solve the technical problem, the application adopts a technical scheme that: a magnetic pigment flake is provided that includes a magnetic reflective layer, and a first dielectric layer and a first absorber layer disposed in a stacked relationship in that order on a first major surface of the magnetic reflective layer, wherein the magnetic reflective layer includes at least one alloy that includes a magnetic material.

According to a specific embodiment of the present application, a second dielectric layer and a second absorber layer are further disposed in sequence on a second major surface of the magnetic reflective layer opposite to the first major surface such that the pigment flakes have a symmetrical structure centered on the magnetic reflective layer.

According to an embodiment of the present application, the first dielectric layer and the second dielectric layer have the same physical thickness, and the physical thickness ranges from 30nm to 900 nm.

According to a specific embodiment of the present application, the material of the first dielectric layer and the second dielectric layer is a dielectric material with a refractive index lower than 2.7.

According to an embodiment of the present disclosure, the material of the first dielectric layer and the second dielectric layer is at least one of silicon dioxide, magnesium fluoride, titanium dioxide, aluminum oxide, and silicon monoxide.

According to a specific embodiment of the present application, the physical thickness of the first and second absorption layers is the same, and the physical thickness ranges from 1nm to 30 nm.

According to a specific embodiment of the present application, the first absorption layer and the second absorption layer are: at least one alloy containing iron, chromium, nickel and manganese components; or a material containing at least one of the metallic simple substances chromium, nickel, titanium, copper, germanium and silicon.

According to one embodiment of the present application, the physical thickness of the magnetic reflective layer ranges from 5nm to 500 nm.

According to a specific embodiment of the present application, the magnetic reflective layer is comprised of a magnetic material having a coercivity greater than 1000 and a remanence greater than 20.

According to a specific embodiment of the present application, the magnetic reflective layer comprises a magnetic material including at least one alloy of iron, chromium, nickel, and manganese components.

According to one embodiment of the present application, the magnetic material comprises the following components in percentage by weight: 50-60% of iron, 10-30% of chromium, 5-20% of nickel and 0.5-2% of manganese.

According to an embodiment of the present application, the magnetic pigment flakes have a physical thickness ranging from 2 μm to 100 μm, and an aspect ratio greater than or equal to 2: 1.

the beneficial effect of this application is: unlike the related art, the magnetic pigment flake of the present application includes a magnetic reflective layer, and a first dielectric layer and a first absorption layer sequentially stacked on a first main surface of the magnetic reflective layer, wherein the magnetic reflective layer includes at least one alloy containing a magnetic material. Through this kind of mode, the magnetic pigment piece of this application adopts magnetic reflection layer to replace traditional magnetic layer and reflection stratum, and magnetic strength is great, has improved the cohesion between magnetic layer and the reflection stratum, has reduced the layering phenomenon, simultaneously, because the structure of this magnetic pigment piece is simpler, has reduced manufacturing cost, and has improved the apparent color saturation of this magnetic pigment piece.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the description of the embodiments are briefly introduced below, it is obvious that the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without inventive efforts, wherein:

fig. 1 is a schematic structural view of magnetic pigment flakes according to an embodiment of the present disclosure;

fig. 2 is a schematic view of another structure of magnetic pigment flakes in accordance with an embodiment of the present disclosure;

FIG. 3 is a graph showing reflectance versus wavelength spectra of magnetic pigment flakes of Experimental group 1 of the examples herein;

FIG. 4 is a schematic optical microscope view of the magnetic pigment flakes of FIG. 3;

FIG. 5 is a graph showing reflectance-wavelength spectra of magnetic pigment flakes of comparative group 1 in examples of the present application;

fig. 6 is an optical microscope representation of the magnetic pigment flakes of fig. 5.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

It should be noted that if directional indications (such as up, down, left, right, front, and back … …) are referred to in the embodiments of the present application, the directional indications are only used to explain the relative positional relationship between the components, the movement situation, and the like in a specific posture (as shown in the drawings), and if the specific posture is changed, the directional indications are changed accordingly.

In addition, if there is a description of "first", "second", etc. in the embodiments of the present application, the description of "first", "second", etc. is for descriptive purposes only and is not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In addition, technical solutions between various embodiments may be combined with each other, but must be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination should not be considered to exist, and is not within the protection scope of the present application.

Some companies introduce magnetic materials into the structure of the common optically variable pigment, the achievement has great innovative significance, the magnetic function is fused into the common optically variable pigment for the first time, however, the product still has the defects: firstly, because the reflectivity of the Co-Ni alloy is low, the performance of the Co-Ni alloy is expressed as that the special metal color and luster and the brightness of the optically variable pigment are insufficient; secondly, the Co-Ni ratio is fixed, so the regulation and control of the magnetism are limited. Thirdly, because the Co-Ni content of the magnetic layer is too high, the magnetic layer is easy to be layered with the dielectric layer, and the performance of the product is seriously influenced.

To solve the above problems, embodiments of the present application provide a magnetic pigment flake.

Referring to fig. 1, fig. 1 is a schematic structural diagram of a magnetic pigment flake according to an embodiment of the present disclosure, the magnetic pigment flake includes a magnetic reflective layer 110, and a first dielectric layer 120 and a first absorption layer 130 sequentially stacked on a first major surface (not shown) of the magnetic reflective layer 110, wherein the magnetic reflective layer 110 includes at least one alloy containing a magnetic material.

Optionally, the magnetic reflective layer 110, the first dielectric layer 120, and the first absorption layer 130 form a 3-layer magnetic pigment flake; the magnetic reflective layer 110 may include at least one alloy material, wherein the magnetic material is contained in the at least one alloy material.

Unlike the related art, the magnetic pigment flake of the present application includes a magnetic reflective layer 110, and a first dielectric layer 120 and a first absorption layer 130 sequentially stacked on a first major surface of the magnetic reflective layer 110, wherein the magnetic reflective layer 110 includes at least one alloy containing a magnetic material. In this way, the magnetic pigment flakes in this embodiment use the magnetic reflective layer 110 to replace the conventional magnetic layer and reflective layer, so that the magnetic strength is high, the binding force between the magnetic layer and the reflective layer is improved, and the delamination phenomenon is reduced.

The magnetic optically variable pigment is characterized in that a magnetic material is added into the structure of the common optically variable pigment to ensure that the optically variable pigment has magnetic characteristics. The multilayer magnetic optically variable pigment has two advantages, on one hand, the magnetism can be used as an information carrier and can record information, and when the pigment is applied to anti-counterfeiting, the pigment not only has an anti-counterfeiting function which can be distinguished by an instrument, but also has a visual color-changing effect, namely, the pigment has anti-counterfeiting characteristics of one line and two lines; on the other hand, when the pigment flakes are used as decorative pigments, the pigment flakes or the ink can be subjected to imaging treatment by magnetizing the pigment flakes and then passing through an external magnetic field, so that the application range of the optically variable pigment flakes is greatly widened.

Referring to fig. 2, fig. 2 is a schematic view of another structure of a magnetic pigment flake according to an embodiment of the present disclosure. Specifically, a second dielectric layer 140 and a second absorption layer 150 are further sequentially stacked on a second main surface (not shown) of the magnetic reflection layer 110 opposite to the first main surface (not shown), so that the pigment flakes have a symmetrical structure centered on the magnetic reflection layer 110.

As shown in fig. 2, the first dielectric layer 120, the first absorption layer 130, the magnetic reflection layer 110, the second dielectric layer 140, and the second absorption layer 150 form a 5-layer symmetrical structure centered on the magnetic reflection layer 110.

Different from the situation of the related technology, the first dielectric layer 120, the first absorbing layer 130, the second dielectric layer 140 and the second absorbing layer 150 in the magnetic pigment flake form a symmetrical structure taking the magnetic reflecting layer 110 as the center, so that the lightness, the saturation and the chromaticity of the magnetic pigment flake are ensured, the binding force between the magnetic layer and the reflecting layer in the magnetic pigment flake is improved, the magnetic strength is increased, and the magnetic pigment flake cannot be layered after being subjected to shearing limit strength and ultrasonic processing; meanwhile, the first dielectric layer 120 and the second dielectric layer 140 protect the magnetic reflective layer 110, and the overall tolerance of the magnetic pigment flakes is improved.

The optical thicknesses of first dielectric layer 120 and second dielectric layer 140 range from 2 times a quarter wavelength at 400nm design wavelength to 9 times a quarter wavelength at 700nm design wavelength. Specifically, the physical thicknesses of the first dielectric layer 120 and the second dielectric layer 140 are the same, and the thickness range is 30nm to 900nm, for example, the physical thicknesses of the first dielectric layer 120 and the second dielectric layer 140 may be 30nm, 31nm, 40nm, 50nm, 100nm, 199nm, 500nm, 850nm, 900nm, or the like.

The material of the first dielectric layer 120 and the second dielectric layer 140 is a dielectric material with a refractive index lower than 2.7, for example, the material of the first dielectric layer 120 and the second dielectric layer 140 may be at least one of silicon dioxide, magnesium fluoride, titanium dioxide, aluminum oxide, and silicon monoxide. That is, the materials of the first dielectric layer 120 and the second dielectric layer 140 may be pure compounds of the above materials, or may be a mixture of the above materials.

Specifically, the materials of the first dielectric layer 120 and the second dielectric layer 140 may be the same material.

Preferably, the material of the first dielectric layer 120 and the second dielectric layer 140 is silicon dioxide.

Specifically, the first and

second absorption layers

130 and 150 have the same physical thickness, and the thickness range thereof is 1nm to 30 nm. For example, the physical thicknesses of the first and

second absorption layers

130 and 150 may be 1nm, 2nm, 4nm, 7nm, 15nm, 19nm, 23nm, 28nm, or 30nm, etc.

The first and

second absorption layers

130 and 150 may be at least one alloy containing iron, chromium, nickel, and manganese components; that is, the first absorption layer 130 and the second absorption layer 150 may be at least one alloy material, wherein the alloy material contains iron, chromium, nickel, and manganese components. Because the chemical property of manganese is more active than that of iron, the corrosion of iron is protected to a certain extent, and the weather resistance of the pigment flake is further improved.

Alternatively, the first absorption layer 130 and the second absorption layer 150 may be a material containing at least one of elemental metals of chromium, nickel, titanium, copper, germanium, and silicon; that is, the first and second absorption layers 130 and 150 may be pure substances composed of the above-mentioned elementary materials, or the first and second absorption layers 130 and 150 may be compounds or mixtures composed of at least two of the above-mentioned elementary materials.

Specifically, the first absorbent layer 130 and the second absorbent layer 150 may be the same material.

Preferably, the first absorption layer 130 and the second absorption layer 150 can be made of elemental metal chromium or titanium.

Specifically, the physical thickness of the magnetic reflective layer 110 ranges from 5nm to 500 nm. For example, the physical thickness of the magnetic reflective layer 110 can be 5nm, 6nm, 15nm, 30nm, 100nm, 250nm, 499nm, or 500nm, etc.

The magnetic reflective layer 110 is composed of a magnetic material having a coercivity greater than 1000 and a remanence greater than 20. For example, the coercivity of the magnetic material of the magnetic reflective layer 110 may be 1000, 1500, 2005, 3450, 4000, 4999, or the like, and specifically, the coercivity may be adjusted according to the thickness; the remanence of the magnetic material of the magnetic reflective layer 110 can be 20, 21, 30, 40, 50, or 100, etc.

The coercive force is: after saturation magnetization, when an external magnetic field returns to zero, the magnetic induction intensity of the magnetic material in the magnetic reflection layer 110 does not return to zero, and the magnetic induction intensity returns to zero only when a magnetic field with a certain magnitude is added in the opposite direction of the magnetization field; the stronger the coercivity, the better the magnetic preservation. After the external magnetic field disappears, the residual magnetization intensity in the magnetic material is the residual magnetism.

Specifically, the magnetic reflective layer 110 contains a magnetic material of at least one alloy containing iron, chromium, nickel, and manganese components. That is, the magnetic material of the magnetic reflective layer 110 may be at least one alloy, wherein the alloy includes iron, chromium, nickel, and manganese components.

Further, the component ratio of the magnetic material is as follows: 50-60% of iron, 10-30% of chromium, 5-20% of nickel and 0.5-2% of manganese. Because the chemical property of manganese is more active than that of iron, the corrosion of iron is protected to a certain extent, and the weather resistance of the pigment flake is further improved.

Specifically, the magnetic pigment flakes have a physical thickness in the range of 2 μm to 100 μm, and an aspect ratio of 2 or more: 1.

wherein, when the magnetic pigment flake is in a shape of a circular slice, the ratio of the radius to the thickness of the circular slice is the ratio of the radius to the thickness of the circular slice; when the magnetic pigment flakes are square flakes, the ratio of the aspect ratio to the thickness of the square flakes is the aspect ratio.

In the embodiment of the application, the multilayer magnetic optically variable pigment flake can be added into ink resin or paint as toner to provide magnetism and color flop. The physical thickness of the multilayer magnetic pigment flakes can be in the range of 2 μm, 3 μm, 5 μm, 10 μm, 20 μm, 50 μm, 85 μm, 99 μm, or 100 μm.

Specifically, the magnetic thin-film pigment flakes have high firmness, excellent color saturation, high habit strength, and low production cost, and thus can be used in the fields of currency, cigarette and wine packaging, security and forgery prevention, and decorative pigment fields such as colorful toys.

Experimental group 1

As shown in fig. 2, the film structure of the magnetic pigment flake sequentially includes a first absorption layer 130, a first dielectric layer 120, a magnetic reflection layer 110, a second dielectric layer 140, and a second absorption layer 150.

Specifically, the material used for the first absorption layer 130 and the second absorption layer 150 is chromium, and the physical thickness of the first absorption layer 130 and the second absorption layer 150 is 10 nm.

Specifically, the material of the first dielectric layer 120 and the second dielectric layer 140 is silicon dioxide, and the physical thickness of the first dielectric layer 120 and the second dielectric layer 140 is 270 nm.

Specifically, the magnetic reflective layer 110 is made of iron, chromium, nickel, and manganese alloy, wherein 60% of iron, 25% of chromium, 15% of nickel, and 1% of manganese; the physical thickness of the magnetic reflective layer 110 is 30 nm.

Referring to fig. 3, fig. 3 is a graph showing reflectance-wavelength spectra of magnetic pigment flakes of experimental group 1 in the example of the present application. Wherein, the ordinate is the reflectivity, and the abscissa is the wavelength; the magnetic pigment flakes obtained by the experiment have high reflectivity.

The optically variable pigment is added with magnetic elements, and is applied to decoration by making magnetic pigment flakes into an ink or paint form, and orienting and moving pigment flake particles under an external magnetic field to form a pattern. If the magnetic pigment particles are more magnetic and more force is applied, the more definite the directional motion of the particles with magnetic pigment particles under the magnetic field, and thus the clearer and more accurate image can be formed. On the premise of ensuring good reflectivity and weather resistance, magnetic materials are selected as materials containing iron and nickel with high proportion, and the number of effective magnetic domains is increased by the comprehensive action of the iron and nickel ferromagnetic materials and other materials, so that the magnetic strength is improved, and the coercive force and remanence are improved.

Specifically, the residual magnetism of the obtained result is 40 through the detection of the magnetic index; the coercivity was 4000.

FIG. 4 is a schematic optical microscopic view of the magnetic pigment flakes of FIG. 3, showing that the magnetic thin film pigment flakes are not delaminated under an optical microscope after the multilayer magnetic pigment flakes are crushed; this demonstrates that the robustness of the magnetic pigment flakes obtained in this experiment is very good.

Control group 1

To illustrate the effect of the solution of the present application on improving the robustness of the film layer of the magnetic pigment flakes, a control experiment was proposed and compared with experiment set 1.

In this control group 1, the structure of the membrane system was: a first absorption layer 130, a first dielectric layer 120, a magnetic reflection layer 110, a second dielectric layer 140, and a second absorption layer 150.

Specifically, the magnetic reflective layer 110 is made of nickel or chromium alloy, wherein 30% of nickel and 70% of chromium are selected, and the physical thickness of the magnetic reflective layer 110 is 30 nm.

Referring to fig. 5, fig. 5 is a graph showing reflectance-wavelength spectra of magnetic pigment flakes of comparative group 1 in examples of the present application. Wherein, the ordinate is the reflectivity, and the abscissa is the wavelength; the magnetic pigment flakes of control 1 had a lower reflectivity than the magnetic pigment flakes of experimental group 1.

Specifically, the magnetic pigment flakes in the control group are subjected to detection of magnetic indexes, and the remanence of the obtained result is 15; the coercivity was 1500.

Referring to fig. 6, fig. 6 is a schematic optical microscope view of the magnetic pigment flakes of fig. 5. After the magnetic pigment flakes obtained in the control group 1 were pulverized, a small amount of delamination of the magnetic pigment flakes was observed under an optical microscope; in experimental group 1, the magnetic pigment flake fragments did not delaminate; this demonstrates that the magnetic pigment flakes obtained from experimental group 1 are very robust, while the magnetic properties of the sample are enhanced by the solution of experimental group 1, as well as by comparison of the magnetic indices.

As described above, the comparison between the reflection spectrum, the magnetic index, and the optical micrograph of the experimental group 1 and the control group 1 shows that the solution of the embodiment of the present application can improve the robustness between the layers and enhance the magnetic properties while ensuring the conventional optical effects.

The above description is only for the purpose of illustrating embodiments of the present invention and is not intended to limit the scope of the present invention, and all modifications, equivalents, and equivalent structures or equivalent processes that can be used directly or indirectly in other related fields of technology shall be encompassed by the present invention.

Claims

1. A magnetic pigment flake comprising a magnetic reflective layer and a first dielectric layer and a first absorber layer disposed in sequence on a first major surface of the magnetic reflective layer, wherein the magnetic reflective layer comprises at least one magnetic material;

wherein the magnetic material comprises at least one alloy of iron, chromium, nickel and manganese components;

wherein the magnetic material comprises the following components in proportion: 50 to 60 percent of iron, 10 to 30 percent of chromium, 5 to 20 percent of nickel and 0.5 to 2 percent of manganese;

the magnetic pigment flakes have a physical thickness in the range of 2 to 100 μm, and the magnetic pigment flakes have an aspect ratio of 2: 1;

when the magnetic pigment flakes are disc-shaped, the ratio of the radius to the disc thickness is the diameter-thickness ratio; when the magnetic pigment flakes are square flakes, the ratio of the radial width to the thickness of the square flakes is the radial-to-thickness ratio.

2. The magnetic pigment flake of claim 1, wherein a second dielectric layer and a second absorber layer are further disposed on a second major surface of the magnetic reflector layer opposite the first major surface in a stacked arrangement such that the pigment flake has a symmetrical structure centered on the magnetic reflector layer.

3. The magnetic pigment flake of claim 2, wherein the first dielectric layer and the second dielectric layer have the same physical thickness, and wherein the physical thickness is in a range from about 30nm to about 900 nm.

4. The magnetic pigment flake of claim 2, wherein the first dielectric layer and the second dielectric layer are dielectric materials having a refractive index of less than 2.7.

5. The magnetic pigment flake of claim 2, wherein the first dielectric layer and the second dielectric layer are made of at least one of silicon dioxide, magnesium fluoride, titanium dioxide, aluminum oxide, and silicon monoxide.

6. The magnetic pigment flake of claim 2, wherein the first absorber layer and the second absorber layer have the same physical thickness, and wherein the physical thickness is in the range of 1nm to 30 nm.

7. The magnetic pigment flake of claim 2, wherein the first and second absorber layers are:

at least one alloy containing iron, chromium, nickel and manganese components; alternatively, the first and second electrodes may be,

the material contains at least one metal simple substance of chromium, nickel, titanium, copper, germanium and silicon.

8. The magnetic pigment flake of claim 1, wherein the magnetic reflective layer has a physical thickness of from about 5nm to about 500 nm.

9. The magnetic pigment flake of claim 1, wherein the magnetically reflective layer comprises a magnetic material having a coercivity greater than 1000 and a remanence greater than 20.