阅读说明：本技术 一种光学薄膜、结构色颜料及光学薄膜的制备方法 (Optical film, structural color pigment and preparation method of optical film ) 是由 郭凌杰 马道远 于 2019-09-27 设计创作，主要内容包括：本申请公开了一种光学薄膜、结构色颜料及光学薄膜的制备方法,所述光学薄膜包括：高低两种折射率交替且层叠设置的多层膜层,所述多层膜层包括一中间膜层；其中,所述中间膜层以及位于所述中间膜层一侧的其他膜层中具有相同折射率的膜层的光学厚度不相同或不完全相同。通过上述方式,本申请能够提高光学薄膜的亮度。(The application discloses optical film, structure color pigment and preparation method of optical film, the optical film comprises: the multilayer film layers are arranged in a stacked mode with the high refractive index and the low refractive index alternately, and each multilayer film layer comprises an intermediate film layer; the optical thicknesses of the middle film layer and the film layers with the same refractive index in the other film layers positioned on one side of the middle film layer are different or not completely the same. Through the mode, the brightness of the optical film can be improved.)

1. An optical film for forming a structured color pigment, the optical film comprising:

the multilayer film layers are arranged in a stacked mode with the high refractive index and the low refractive index alternately, and each multilayer film layer comprises an intermediate film layer;

the optical thicknesses of the middle film layer and the film layers with the same refractive index in the other film layers positioned on one side of the middle film layer are different or not completely the same.

2. An optical film as recited in claim 1,

the optical thicknesses of the middle film layer and other film layers positioned on one side of the middle film layer are different; and/or the presence of a gas in the gas,

the difference of the refractive indexes of the high refractive index film layer and the low refractive index film layer is more than or equal to 0.2.

3. An optical film according to claim 1 or 2,

the other film layers on the two sides of the middle film layer are asymmetrically arranged relative to the middle film layer, and the optical thickness and/or the refractive index of the film layers at the corresponding positions on the two sides of the middle film layer are completely different.

4. An optical film according to claim 1 or 2,

the other film layers on the two sides of the middle film layer are symmetrically arranged around the middle film layer, and the optical film is characterized in that: a is₁H a₂La₃H a₄L……a₄La₃H a₂La₁H；

Wherein H represents a high refractive index film layer and has an optical thickness of 1/4 lambda_H(ii) a L represents a low refractive index film layer, andoptical thickness of 1/4 lambda_L，a₁、a₂、a₃、a₄… is the coefficient, a₂、a₃、a₄… is in the range of 0.1-5, a₁Is 0 or 0.1-5.

5. An optical film as recited in claim 4,

the optical thickness of the high refractive index film layer in the optical film is greater than or equal to 30 nanometers and less than or equal to 1000 nanometers, the optical thickness of the low refractive index film layer is greater than or equal to 40 nanometers and less than or equal to 1000 nanometers, and/or the number of the film layers in the optical film can be 3-30.

6. An optical film as recited in claim 5,

the middle film layer is a low refractive index film layer or a high refractive index film layer; and/or the presence of a gas in the gas,

the intermediate film layer is made of a simple substance or a compound; wherein the simple substance comprises at least one of the following substances: carbon, silicon, germanium, aluminum, nickel, titanium, chromium, tungsten, gold, silver, platinum, palladium; the compound includes at least one of: oxides, fluorides, sulfides, hydroxides, nitrides, carbides, chlorides.

7. An optical film as recited in claim 6,

the total number of the film layers of the optical film is 7;

wherein the optical film is a red optical film, and the optical film comprises the following layers from the first layer to the seventh layer: a high refractive index film layer with optical thickness of 90-315 nanometers, a low refractive index film layer with optical thickness of 70-220 nanometers, a high refractive index film layer with optical thickness of 67-270 nanometers, a low refractive index film layer with optical thickness of 130-260 nanometers, a high refractive index film layer with optical thickness of 67-270 nanometers, a low refractive index film layer with optical thickness of 70-220 nanometers and a high refractive index film layer with optical thickness of 90-315 nanometers; or the like, or, alternatively,

the optical film is a green optical film, and the optical film comprises the following layers from the first layer to the seventh layer: the high-refractive-index film layer with the optical thickness of 270-450 nm, the low-refractive-index film layer with the optical thickness of 340-460 nm, the high-refractive-index film layer with the optical thickness of 315-490 nm, the low-refractive-index film layer with the optical thickness of 333-450 nm, the high-refractive-index film layer with the optical thickness of 315-490 nm, the low-refractive-index film layer with the optical thickness of 340-460 nm and the high-refractive-index film layer with the optical thickness of 270-450 nm; or the like, or, alternatively,

the optical film is a blue optical film, and the optical film comprises the following layers from the first layer to the seventh layer: the film comprises a high-refractive-index film layer with an optical thickness of 60-230 nanometers, a low-refractive-index film layer with an optical thickness of 40-220 nanometers, a high-refractive-index film layer with an optical thickness of 60-230 nanometers, a low-refractive-index film layer with an optical thickness of 40-180 nanometers, a high-refractive-index film layer with an optical thickness of 60-230 nanometers, a low-refractive-index film layer with an optical thickness of 40-220 nanometers and a high-refractive-index film layer with an optical thickness of 60.

8. An optical film as recited in claim 1,

the material of the film layer in the optical film is a compound, wherein the material of the high-refractive-index film layer comprises an oxide or a sulfide, the oxide comprises at least one of titanium oxide, zirconium oxide, aluminum oxide, tantalum oxide and hafnium oxide, and the sulfide comprises zinc sulfide; the low refractive index film layer comprises the following materials: at least one of silicon monoxide, silicon dioxide, magnesium fluoride, calcium fluoride and sodium hexafluoroaluminate.

9. A structured color pigment, wherein the structured color pigment is a flake of the optical film of any one of claims 1-8, wherein the total number of layers of each of the flakes is the same as the total number of layers of the optical film, and wherein the optical properties of the layers of each of the flakes are the same as the optical properties of the optical film.

10. A method of making an optical film for forming a structured color pigment, the method comprising:

forming an optical film on a substrate, wherein the optical film comprises a plurality of layers with alternating high and low refractive indexes and arranged in a stacked manner, and the plurality of layers comprise an intermediate layer; the optical thicknesses of the middle film layer and the film layers with the same refractive index in the other film layers positioned on one side of the middle film layer are different or not completely the same.

Technical Field

The application relates to the technical field of optical films, in particular to an optical film, a structural color pigment and a preparation method of the optical film.

Background

The structural color, also called physical color, is a physical color-generating effect in which a micro-nano structure of a light wavelength scale interacts with light to form interference, diffraction or scattering to generate color. The structural color pigment as a new generation pigment has a series of important advantages of high brightness, high color saturation, no toxicity, no fading, high temperature resistance, environmental protection and the like.

The inventor of the application finds that the existing structural color pigment has the problem of low brightness in the long-term research process.

Disclosure of Invention

The technical problem mainly solved by the application is to provide the optical film, the structural color pigment and the preparation method of the optical film, so that the brightness of the optical film can be improved, and the reflectivity R is more than 80%.

In order to solve the technical problem, the application adopts a technical scheme that: an optical film for forming a structured color pigment is provided, the optical film comprising: the multilayer film layers are arranged in a stacked mode with the high refractive index and the low refractive index alternately, and each multilayer film layer comprises an intermediate film layer; the optical thicknesses of the middle film layer and the film layers with the same refractive index in the other film layers positioned on one side of the middle film layer are different or not completely the same.

In order to solve the above technical problem, another technical solution adopted by the present application is: providing a structured color pigment, wherein the structured color pigment is fragments of the optical film described in any one of the embodiments, the total number of layers of each of the fragments is the same as the total number of layers of the optical film, and the optical properties of the layers of each of the fragments are the same as the optical properties of the optical film.

In order to solve the above technical problem, the present application adopts another technical solution: provided is a method of manufacturing an optical film for forming a structured color pigment, the method including: forming an optical film on a substrate, wherein the optical film comprises a plurality of layers with alternating high and low refractive indexes and arranged in a stacked manner, and the plurality of layers comprise an intermediate layer; the optical thicknesses of the middle film layer and the film layers with the same refractive index in the other film layers positioned on one side of the middle film layer are different or not completely the same.

The beneficial effect of this application is: different from the situation of the prior art, the optical film provided by the application comprises a plurality of film layers with two refractive indexes of high and low alternately and arranged in a stacked mode, and the design mode of the plurality of film layers is beneficial to increasing the reflection effect of visible light, so that the brightness of the optical film can be increased, and the brightness of the structural color pigment formed by the optical film subsequently is improved. In addition, the optical thicknesses of the middle film layer in the optical film and the film layers with the same refractive index in other film layers positioned on one side of the middle film layer are different or not completely the same, so that the structure of the optical film is more diversified and the color is more vivid.

In addition, the optical film provided by the application can not contain a material for absorbing light, and the reflectivity of the optical film to the light can be close to 100%, so that the brightness and the color vividness can be further improved. In addition, the material of the optical film provided by the application can reduce environmental pollution and reduce cost if the material does not contain simple substance metal.

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, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts. Wherein:

FIG. 1 is a schematic structural diagram of an embodiment of an optical film according to the present disclosure;

FIG. 2 is a schematic flow chart illustrating one embodiment of a method for making an optical film according to the present disclosure;

FIG. 3 is a schematic view of a spectral curve of an optical thin film according to an embodiment;

FIG. 4 is a schematic view of a spectroscopic curve of the optical film in example two;

FIG. 5 is a schematic view of the spectral curve of the optical film in the third embodiment.

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 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.

Structured color pigments based on optical films can currently be divided into two broad categories: chameleon pigments and omnidirectional pigments. Wherein the chameleon pigment has different colors when observed at different angles, for example, the characters of '100' on RMB; the color of the omnidirectional color pigment is close to and slightly changes when the pigment is observed at different angles.

The principle of color generation by structured color pigments based on optical films is similar to that of pearlescent pigments. When a certain beam of light is incident on the optical film and meets the first layer interface, part of the beam of the incident light is reflected at a certain angle, and the other part of the beam of the incident light is refracted; when the refracted light hits the second layer interface, it is reflected to the first layer interface with another angle intensity and phase, and continues to be refracted. The color of the finally obtained reflected light varies depending on the number of layers, the thickness of the film layer, the refractive index of the film layer, and the like, and is determined by the coherent enhancement or the destructive attenuation of light in a certain wavelength band.

Referring to fig. 1, fig. 1 is a schematic structural diagram of an embodiment of an optical film according to the present disclosure. The optical film is used to form a structured color pigment, the optical film comprising: the multilayer film layer comprises a middle film layer 10, the number of layers of the multilayer film layer in the optical film is odd, and can be 3-30, for example, 3 layers, 5 layers, 7 layers, 9 layers and the like, and the refractive indexes of the multilayer film layer can be sequentially arranged in a high refractive index-low refractive index-high refractive index mode, or the refractive indexes of the multilayer film layer can be sequentially arranged in a low refractive index-high refractive index-low refractive index mode. In addition, in the present embodiment, the optical thicknesses of the intermediate film layer 10 and the other film layers 12 located on one side of the intermediate film layer 10, which have the same refractive index, are different; for example, when the number of layers having a high refractive index/low refractive index of the intermediate film layer 10 and the other film layers 12 on the side of the intermediate film layer 10 in the optical film is 2 or more, the optical thicknesses of the high refractive index film layers/the low refractive index film layers are different from each other. Of course, the optical thicknesses of the intermediate film layer 10 and the other film layers 12 on the side of the intermediate film layer 10, which have the same refractive index, may not be completely the same; for example, when the number of layers having a high refractive index/low refractive index of the intermediate layer 10 and the other layers 12 on the side of the intermediate layer 10 in the optical film is 3, the optical thicknesses of 2 layers of the high refractive index/low refractive index layers are the same.

The optical thicknesses of the middle film layer 10 and the other film layers 12 on one side of the middle film layer 10 in the optical film, which have the same refractive index, are different or not completely the same, so that the structure of the optical film is more various and the color is more vivid.

In one embodiment, the other film layers on both sides of the middle film layer 10 may be asymmetrically disposed with respect to the middle film layer 10, and the optical thickness and/or refractive index of the film layers at the corresponding positions on both sides of the middle film layer 10 may be completely different. For example, as shown in fig. 1, two first film layers 14a, 14b immediately adjacent to the intermediate film layer 10, the optical thicknesses and/or refractive indices of the two first film layers 14a, 14b may be different; and so on, the optical thicknesses and/or refractive indices of the two film layers adjacent the second and third … of the middle film layer 10 may be different. The design mode can make two sides of the optical film reflect light with different colors. When the optical film is mixed after being pulverized into flake particles, a composite color of two colors can be generated, increasing the width of the color gamut, which is an extremely effective and simple strategy for generating a third color.

In one embodiment, the optical thickness of the intermediate film layer 10 and the other film layers 12 on one side of the intermediate film layer 10 in the optical film provided by the present application are different, that is, the optical thickness of all the film layers in the optical film is different. The design mode can make the structure of the optical film more various and the color more bright.

In an application scene, the other film layers on the two sides of the middle film layer 10 are symmetrically arranged relative to the middle film layer, and the symmetrical arrangement mode is favorable for increasing the reflection effect of visible light, so that the brightness of the optical film can be increased, and the brightness of the structural color pigment formed by the optical film subsequently is improved. The optical film is formulated as follows: a is₁H a₂La₃H a₄L……a₄L a₃H a₂L a₁H, wherein H represents a high refractive index film layer and has an optical thickness of 1/4 lambda_HL represents a low refractive index film layer, andoptical thickness of 1/4 lambda_L，a₁、a₂、a₃、a₄… is a coefficient. A above₂、a₃、a₄… is in the range of 0.1-5, a₁The value of (A) is in the range of 0, or, 0.1 to 5. Wherein, the intermediate film layer 10 and the other film layers 12 on one side of the intermediate film layer 10 have the same refractive index a₁、a₃…, and further, the intermediate film layer 10 and the other film layers 12 on one side of the intermediate film layer 10 have a₁、a₂、a₃、a₄… are all different. Preferably, a above₁、a₂、a₃、a₄… are all not 1.

In one application scenario, the minimum value of the optical thicknesses of the low refractive index film layers is greater than the maximum value of the optical thicknesses of the high refractive index film layers. This design may further reduce costs.

In yet another application scenario, the optical thickness of the high refractive index film layer in the optical film is greater than or equal to 30nm and less than or equal to 1000 nm (e.g., 30nm, 100 nm, 200 nm, 300 nm, 700 nm, 900 nm, etc.), and the optical thickness of the low refractive index film layer is greater than or equal to 40 nm and less than or equal to 1000 nm (e.g., 40 nm, 150 nm, 250 nm, 400nm, 800 nm, 1000 nm, etc.).

In another application scenario, the intermediate film layer in the optical film layer is a low refractive index film layer, and the design manner is lower in cost than the design manner in which the intermediate film layer is a high refractive index film layer. Of course, the intermediate film layer may also be a high refractive index film layer. The material of the intermediate film layer can be a simple substance or a compound, wherein the simple substance comprises at least one of the following substances: carbon, silicon, germanium, aluminum, nickel, titanium, chromium, tungsten, gold, silver, platinum, palladium; the compound comprises at least one of the following: oxides, fluorides, sulfides, hydroxides, nitrides, carbides, chlorides. The oxide can be silicon monoxide, silicon dioxide, titanium oxide, zirconium oxide, aluminum oxide, tantalum oxide, hafnium oxide, etc.; the fluoride can be magnesium fluoride, calcium fluoride, sodium hexafluoroaluminate and the like; the sulfide can be zinc sulfide, cadmium sulfide, etc.; the hydroxide can be aluminum hydroxide, sodium hydroxide, potassium hydroxide, calcium hydroxide, etc.; the nitride may be potassium nitride, aluminum nitride, boron nitride, or the like; the carbide can be silicon carbide, chromium carbide and the like; the chloride can be sodium chloride, potassium chloride, calcium chloride, etc.

When the total number of the layers of the optical film is 7, the optical film is a red optical film, and the optical film comprises the following layers from the first layer to the seventh layer: a high refractive index film layer of optical thickness 90-315 nm (e.g., 90 nm, 200 nm, 315 nm, etc.), a low refractive index film layer of optical thickness 70-220 nm (e.g., 70 nm, 140 nm, 220 nm, etc.), a high refractive index film layer of optical thickness 67-270 nm (e.g., 67 nm, 150 nm, 270 nm, etc.), a low refractive index film layer of optical thickness 130-260 nm (e.g., 130 nm, 190 nm, 260 nm, etc.), a high refractive index film layer of optical thickness 67-270 nm (e.g., 67 nm, 150 nm, 270 nm, etc.), a low refractive index film layer of optical thickness 70-220 nm (e.g., 70 nm, 140 nm, 220 nm, etc.), a high refractive index film layer of optical thickness 90-315 nm (e.g., 90 nm, 200 nm, 315 nm, etc.); or the like, or, alternatively,

the optical film is a green optical film, and the optical film comprises the following layers from the first layer to the seventh layer: a high refractive index film layer with an optical thickness of 270-450 nm (e.g., 270 nm, 350 nm, 450 nm, etc.), a low refractive index film layer with an optical thickness of 340-460 nm (e.g., 340 nm 400nm, 460 nm, etc.), a high refractive index film layer with an optical thickness of 315-490 nm (e.g., 315 nm, 400nm, 490 nm, etc.), a low refractive index film layer with an optical thickness of 333-450 nm (e.g., 333 nm, 395 nm, 450 nm, etc.), a high refractive index film layer with an optical thickness of 315-490 nm (e.g., 315 nm, 400nm, 490 nm, etc.), a low refractive index film layer with an optical thickness of 340-460 nm (e.g., 340 nm 400nm, 460 nm, etc.), and a high refractive index film layer with an optical thickness of 270-450 nm (e.g., 270 nm, 350 nm, 450 nm, etc.); or the like, or, alternatively,

the optical film is a blue optical film, and the optical film comprises the following layers from the first layer to the seventh layer: a high refractive index film layer of optical thickness 60-230 nanometers (e.g., 60 nanometers, 150 nanometers, 230 nanometers, etc.), a low refractive index film layer of optical thickness 40-220 nanometers (e.g., 40 nanometers, 130 nanometers, 220 nanometers, etc.), a high refractive index film layer of optical thickness 60-230 nanometers (e.g., 60 nanometers, 150 nanometers, 230 nanometers, etc.), a low refractive index film layer of optical thickness 40-180 nanometers (e.g., 40 nanometers, 110 nanometers, 180 nanometers, etc.), a high refractive index film layer of optical thickness 60-230 nanometers (e.g., 60 nanometers, 150 nanometers, 230 nanometers, etc.), a low refractive index film layer of optical thickness 40-220 nanometers (e.g., 40 nanometers, 130 nanometers, 220 nanometers, etc.), a high refractive index film layer of optical thickness 60-230 nanometers (e.g., 60 nanometers, 150 nanometers, 230 nanometers, etc.).

In other embodiments, the total number of layers of the optical film may also be 3, and four layers adjacent to two sides of the middle layer 10 may be removed; of course, the total number of optical film layers may also be 5, and the outermost two film layers may be removed; the total number of optical film layers may also be 9, in which case one film layer may be added to each outermost side of the two sides. The parameters of the optical film, such as the number of specific film layers, the material and the refractive index of each film layer, the thickness of each film layer and the like, can be set according to the actual situation, so that the adaptability and the application universality of the optical film are fully improved.

In still another embodiment, the difference between the refractive indexes of the high refractive index film layer and the low refractive index film layer is greater than or equal to 0.2, for example, 0.2, 0.4, 0.9, etc., which can make the brightness and vividness of the color of the formed optical film better, and the reflectivity of the formed optical film is greater than or equal to 80%, so that the brightness of the optical film is higher.

In this embodiment, the material of the film layer in the optical film is a compound, and the material does not contain elemental metal, so that the environmental pollution can be reduced, and the cost can be reduced; further, since the compound does not absorb light, the reflectance with respect to light can approach 100%, and thus, the luminance and the color vividness can be further improved. The material of the high-refractive-index film layer comprises an oxide or a sulfide, wherein the oxide comprises at least one of titanium oxide, zirconium oxide, aluminum oxide, tantalum oxide and hafnium oxide, and the sulfide comprises zinc sulfide; the low refractive index film layer comprises the following materials: at least one of silicon oxide, magnesium fluoride, calcium fluoride and sodium hexafluoroaluminate.

In addition, in the present embodiment, the optical film provided by the present application may further include a substrate, where the substrate may be glass, plastic, metal, or the like, and the substrate may cover at least one film layer outermost in the lamination direction; that is, the structure of the optical film may be substrate-multilayer film layer, or substrate-multilayer film layer-substrate.

The present application also provides a structured color pigment, the structured color pigment being fragments of the optical film of any of the above embodiments, the total number of layers of the film layer of each fragment being the same as the total number of layers of the optical film, the optical properties of the film layer of each fragment being the same as the optical properties of the optical film.

In an application scene, the optical film can be formed into micron-sized fragments by an ultrasonic crushing method, so that the structural color pigment is obtained.

And further, physically mixing the obtained structural color pigment with the viscous solution according to a preset mass ratio, and uniformly stirring to obtain the coating containing the structural color pigment. Wherein, the viscous solution can be optical epoxy glue and the like. The mass of the structural color pigment accounts for 1-70% of the total mass of the coating, for example, 1%, 3%, 35%, 55%, 70%, etc.

Referring to fig. 1 and fig. 2 together, fig. 2 is a schematic flow chart illustrating a method for manufacturing an optical film according to an embodiment of the present disclosure, the method including:

s101: forming an optical film on a substrate, wherein the optical film comprises a plurality of layers with alternating high and low refractive indexes and arranged in a stacked manner, and the plurality of layers comprise an intermediate layer 10; the optical thicknesses of the middle film layer 10 and the other film layers 12 on one side of the middle film layer 10 having the same refractive index are not the same or not completely the same.

Specifically, the substrate may be a transparent glass substrate, polyethylene hard plastic, or the like. In addition, the implementation manner of the step S101 may be: the method comprises the steps of sequentially forming a plurality of layers of stacked film layers on a substrate in a vacuum evaporation mode and the like, and monitoring the optical thickness of the film layer being formed while forming the film layers so that the formed optical thickness meets the requirement.

In an embodiment, after the step S101, the preparation method provided by the present application further includes: and stripping the substrate. Specifically, before the step S101, a layer of release agent (e.g., sodium chloride, etc.) may be coated on the surface of the substrate. The step of peeling off the substrate may be to put the whole formed in step S101 into a peeling solution to perform a film removal treatment.

In other embodiments, the substrate may not be peeled, and the present application is not limited thereto.

In the following, several specific examples are given to further illustrate the optical films provided herein.