KR20230134012A - Photonic crystal structure and manufacturing method thereof - Google Patents

Abstract

The present invention relates to a laminate, which can exhibit color changes due to temperature changes and color changes due to humidity changes, and can exhibit color changes in various stages.

Description

Photonic crystal structure and method of manufacturing the same {PHOTONIC CRYSTAL STRUCTURE AND MANUFACTURING METHOD THEREOF}

The present invention relates to photonic crystal structures and methods for manufacturing the same.

A photonic crystal is a structure in which dielectric materials with different refractive indexes are periodically arranged. Overlapping interference occurs between light scattered from each regular lattice point, thereby selectively transmitting light in a specific wavelength range. It refers to a material that reflects, that is, forms an optical band gap.

These photonic crystals use photons instead of electrons as a means of processing information, and thus have excellent information processing speeds, making them a key material for improving the efficiency of the information industry. Moreover, photonic crystals can be implemented as a one-dimensional structure in which photons move in the direction of the main axis, a two-dimensional structure in which photons move along a plane, or a three-dimensional structure in which photons move freely in all directions throughout the material, and can be implemented as a three-dimensional structure in which photons move freely in all directions through the material, It is easy to control optical properties and can be applied to various fields. For example, photonic crystals can be applied to optical devices such as photonic crystal fibers, light-emitting devices, photovoltaic devices, photonic crystal sensors, and semiconductor lasers.

In particular, the Bragg stack is a photonic crystal with a one-dimensional structure, which can be easily manufactured by simply stacking two layers with different refractive indices, and has the advantage of easy control of optical properties by adjusting the refractive index and thickness of the two layers. There is. Due to these characteristics, the Bragg stack is widely used not only in energy devices such as solar cells, but also in photonic crystal sensors that detect electrical, chemical, and thermal stimulation. Accordingly, research is being conducted on various materials and structures to easily manufacture photonic crystal sensors with excellent sensitivity and reproducibility.

Korean Patent Publication No. 10-2016-0044217

The purpose of the present invention is to provide a laminate whose color can be changed in several stages by stimulation of the external environment.

The purpose of the present invention is to provide a color conversion sensor including the above laminate.

The purpose of the present invention is to provide an anti-counterfeiting film including the above laminate.

1. A laminate including a Zion pigment layer and a humidity-sensitive color conversion photonic crystal structure laminated on the Zion pigment layer.

2. The laminate of 1 above, wherein the temperature pigment layer changes color at a temperature above room temperature but below body temperature.

3. The laminate of 1 above, wherein the Zion pigment layer changes color from black to white or from white to black in response to temperature.

4. The laminate of 1 above, wherein the color conversion photonic crystal structure includes alternating low refractive index layers and high refractive index layers, and the low refractive index layer is more hydrophilic than the high refractive index layer.

5. The laminate of item 4 above, wherein the low refractive index layer contains an inorganic salt.

6. The laminate according to item 5 above, wherein the refractive index of the high refractive index layer is higher than the refractive index of the inorganic salt.

7. The laminate of 1 above, wherein the polymer included in the low refractive index layer of the color conversion photonic crystal structure is a copolymer containing a repeating unit represented by the following formula (1):

[Formula 1]

(wherein R ₁ and R ₂ are each independently hydrogen or C1-3 alkyl,

R ₃ is represented by the following formula 2 or 3,

R ₄ is O or NH,

R ₅ is benzoylphenyl,

The benzoylphenyl is unsubstituted or substituted with 1 to 4 substituents each independently selected from the group consisting of hydroxy, halogen, nitro, C1-5 alkyl, and C1-5 alkoxy,

n and m are each independently integers of 1 or more,

n+m is 100 to 2,000.)

[Formula 2]

(Wherein, R ₆ is O, NH or ego,

R ₇ is H, OH, C1~10 alkyl, C1~10 aminoalkyl, C1~10 alkoxy or ego,

l is an integer from 1 to 20, and o is an integer from 1 to 10.)

[Formula 3]

(where p is an integer from 1 to 4).

8. The laminate according to item 7 above, wherein the copolymer is one of copolymers containing repeating units represented by the following formulas 1-1 to 1-10.

[Formula 1-1]

[Formula 1-2]

[Formula 1-3]

[Formula 1-4]

[Formula 1-5]

[Formula 1-6]

[Formula 1-7]

[Formula 1-8]

[Formula 1-9]

[Formula 1-10]

(In the formula, n and m are each independently an integer of 1 or more,

n+m is 100 to 2,000,

l is an integer from 1 to 20).

9. The laminate of 1 above, wherein the polymer included in the high refractive index layer of the color conversion photonic crystal structure is a copolymer containing a repeating unit represented by the following formula 4 or 5:

[Formula 4]

[Formula 5]

(Wherein, R ₃ to R ₆ are each independently hydrogen or C1-3 alkyl,

A ₁ and A ₂ are each independently a C6-20 aromatic ring or a C2-20 heteroaromatic ring,

R ₁₁ to R ₁₃ are each independently hydroxy, cyano, nitro, amino, halogen, SO ₃ H, SO ₃ (C1-5 alkyl), C1-10 alkyl or C1-10 alkoxy, or are linked to each other and represent C4 Can form an aromatic ring of -12,

a1 to a3 are each independently an integer from 0 to 5,

L ₂ and L ₃ are each independently O or NH,

Y ₂ and Y ₃ are each independently benzoylphenyl,

Y ₂ and Y ₃ are unsubstituted or substituted with 1 to 4 substituents each independently selected from the group consisting of hydroxy, halogen, nitro, C1-5 alkyl, and C1-5 alkoxy,

n' and m' are each independently integers of 1 or more,

n'+m' is 100 to 2,000,

n" and m" are each independently integers of 1 or more,

n"+m" is from 100 to 2,000).

10. The laminate according to item 9 above, wherein the copolymer is a copolymer containing a repeating unit represented by the following formula 5-1 or 5-2.

[Formula 5-1]

[Formula 5-2]

(In the formula, n" and m" are each independently an integer of 1 or more, and n"+m" is 100 to 2,000.)

11. In item 5 above, the inorganic salt is LiCl, NaCl, KCl, AlCl ₃ , MgCl ₂ , CaCl ₂ , LiTFSi, LiBr, NaBr, KBr, AlBr ₃ , MgBr ₂ , CaBr ₂ , LiI, NaI, KI, AlI ₃ , MgI ₂ , and CaI _2. A laminate containing at least one selected from the group consisting of.

12. A color conversion sensor comprising the laminate of any one of items 1 to 11 above.

13. An anti-counterfeiting film comprising the laminate of any one of items 1 to 11 above.

The laminate of the present invention can exhibit color changes due to temperature changes and also color changes due to humidity changes, and can exhibit color changes in various stages.

The laminate of the present invention has excellent sensitivity to changes in humidity.

Figure 1 briefly shows the structure of a photonic crystal structure according to an embodiment of the present invention.
Figure 2 shows the change in reflectivity when blowing on the film prepared in Comparative Example 1.
Figure 3 shows the change in reflectivity when blowing on the film prepared in Example 1.
Figure 4 shows the change in reflectivity when blowing on the film prepared in Example 2.
Figure 5 shows the change in reflectivity when blowing on the film prepared in Example 3.
Figure 6 shows the results of Comparative Example 1 and Examples 1 to 3 (Figures 2 to 5).
Figure 7 shows the change in reflectivity when blowing on the film prepared in Example 26.
Figure 8 shows the color change according to the temperature change of the Zion pigment layer.
Figure 9 shows color changes according to changes in temperature and humidity of the laminate.
Figure 10 shows the change in reflection wavelength according to the change in humidity of the color conversion photonic crystal structure manufactured in Example ~.
Figures 11 and 12 show color changes according to temperature and humidity changes.
Figure 13 is a schematic diagram showing the principle of how the color of the laminate changes depending on the color of the Zion pigment layer.

Hereinafter, the present invention will be described in detail.

The term 'photonic crystal' used in the present invention is a structure in which dielectric materials with different refractive indexes are periodically arranged, and overlapping interference occurs between light scattered from each regular lattice point, resulting in a specific wavelength region. It refers to a material that selectively reflects light without transmitting it, that is, forming an optical band gap. These photonic crystals are materials with excellent information processing speed by using photons instead of electrons as a means of processing information. They have a one-dimensional structure in which photons move in the direction of the main axis, a two-dimensional structure in which photons move along a plane, or a material that moves in all directions throughout the material. It can be implemented as a three-dimensional structure that moves freely. In addition, it can be applied to optical devices such as photonic crystal fibers, light-emitting devices, photovoltaic devices, color conversion films, and semiconductor lasers by controlling the optical properties by adjusting the optical band gap of the photonic crystal.

In addition, the term 'photonic crystal structure' used in the present invention refers to a Bragg stack having a one-dimensional photonic crystal structure manufactured by repeatedly alternately stacking materials with different refractive indices, which are formed by periodic differences in the refractive indices of the stacked structures. It refers to a structure that can reflect light in a specific wavelength range, and this reflected wavelength is shifted by an external stimulus to change the reflected color. Specifically, partial reflection of light occurs at the boundaries of each layer of the structure, and many of these reflected waves structurally interfere, causing light of a specific wavelength with high intensity to be reflected. At this time, the shift of the reflected wavelength due to the external stimulus occurs as the wavelength of the scattered light changes as the lattice structure of the material forming the layer changes due to the external stimulus. The optical properties of this photonic crystal structure can be controlled by adjusting the refractive index and thickness, and can be manufactured in the form of a coating film coated on a separate substrate or substrate, or in the form of a free-standing film.

The present invention relates to a laminate including a Zion pigment layer and a humidity-sensitive color conversion photonic crystal structure laminated on the Zion pigment layer.

Zion pigment is a pigment that changes color depending on temperature (thermochromic pigment), and the Zion pigment layer refers to a layer formed by applying a paint containing such a Zion pigment. The Zion pigment layer may be composed only of a paint layer containing the Zion pigment, may include a base coated with the paint, or may include an ultraviolet ray blocking layer, an oxygen blocking layer, etc. additionally laminated on the paint.

The UV blocking layer and oxygen blocking layer may be additionally coated on the paint, or may be a UV blocking film attached to the paint. When both the ultraviolet ray blocking layer and the oxygen blocking layer are included, the stacking order of these layers is not limited.

Zion pigments known in the art can be used without limitation.

Zion pigments of various colors and Zion pigments that change color into various colors can be used, and the color change is preferably changed to brightness contrast, color contrast, saturation contrast, or two or more of these contrasting colors in terms of improving visibility. It may be. For example, it can change from white to black or from black to white so that the brightness contrast is high, and it can also have various colors with contrasting brightness and change into various colors. Additionally, for example, it may be changed to an opposite color on the color wheel or a color that is close to the opposite color on the color wheel to increase color contrast. Also, for example, it may be changing from a high-saturation color to a low-saturation color or from a low-saturation color to a high-saturation color so that the saturation contrast is large. Combinations of these contrasts are also possible.

The color conversion temperature of the Zion pigment is not limited, but in terms of showing a color change due to use by the user, for example, contact with body temperature, the color conversion temperature may be a temperature above room temperature or below body temperature.

Figure 8 is an example photo of the Zion pigment layer, and it can be seen that the color changes from white before temperature sensitivity to black after temperature sensitivity.

Components other than the Zion pigment included in the paint containing the Zion pigment may be any component known in the art without limitation. For example, binders, solvents, anti-settling agents, anti-foaming agents, leveling agents, UVA blockers, etc. may be used, and known components may be used without limitation.

The color conversion photonic crystal structure is laminated on the Zion pigment layer.

As described above, the photonic crystal structure has a one-dimensional photonic crystal structure manufactured by repeatedly alternately stacking materials with different refractive indices. For example, as shown in Figure 1, a first refractive index layer and a second refractive index layer are alternately stacked. It means. The total number of stacks of the first refractive index layer and the second refractive index layer may be, for example, 3 to 30 layers, but is not limited thereto.

The first refractive index and the second refractive index are different, and the first refractive index layer may be lower than the second refractive index.

The first refractive index layer may have a thickness of, for example, 5 to 100 nm, and the second refractive index layer may have a thickness of, for example, 50 to 150 nm, but are not limited thereto.

Specifically, when multi-colored white light is incident on the photonic crystal structure according to the present invention, partial reflection of the incident light occurs at the boundary of each layer, and the interference of the partially reflected lights causes the reflection wavelength (λ) to be concentrated into one wavelength. Indicates the color according to the color. The reflection wavelength (λ) of the photonic crystal structure can be determined by the following equation 1:

[Equation 1]

λ= 2(n1*d1 + n2*d2)

In the above formula, n1 and n2 refer to the refractive indices of the first refractive index layer and the second refractive index layer, respectively, and d1 and d2 refer to the thicknesses of the first refractive index layer and the second refractive index layer, respectively. Therefore, the desired reflection wavelength (λ) can be achieved by adjusting the types of the first and second polymers described later, the thickness of the first refractive index layer and the second refractive index layer, and the total number of stacks of the first refractive index layer and the second refractive index layer. there is.

The reflection wavelength of the photonic crystal structure is shifted due to swelling of the first polymer and/or the second polymer included in the photonic crystal structure due to an external stimulus. This is because when the first polymer and/or the second polymer swells, the crystal lattice structure of each refractive index layer changes and the form of light scattered at the interface of each layer changes. That is, the photonic crystal structure displays a converted color due to the shifted reflection wavelength (λ'), and the presence of an external stimulus can be confirmed by this color conversion of the photonic crystal structure. In particular, when the reflection wavelength (λ) and the shifted reflection wavelength (λ') of the photonic crystal structure are within the range of 380 nm to 760 nm, which is the visible light region, the color conversion of the photonic crystal structure can be easily confirmed with the naked eye.

Specifically, the color conversion of the photonic crystal structure may occur when the reflection wavelength of the photonic crystal structure is shifted due to swelling of the first or second polymer due to the external stimulus, for example, relative humidity of 70% or more.

The reason that the photonic crystal structure according to the present invention shows no or almost no color change at a relative humidity of less than 70% is due to its appropriate hydrophilicity, and this hydrophilicity can be realized by changing the monomer composition of the photonic crystal structure.

Hereinafter, the schematic structure of the photonic crystal structure 10 included in the color conversion film according to an embodiment of the present invention will be described with reference to FIG. 1.

Referring to FIG. 1, the photonic crystal structure 10 according to an embodiment of the present invention includes first refractive index layers 11 and second refractive index layers 12, which are alternately stacked.

At this time, the first refractive index layer 11 may be located at the top of the photonic crystal structure. Accordingly, the first refractive index layer 11 is additionally laminated on a laminate in which the first refractive index layers 11 and the second refractive index layers 12 are alternately laminated, so that the photonic crystal structure has an odd number of refractive index layers. You can have it. In this case, as described above, constructive interference between lights reflected at the interface of each layer increases, and the intensity of the reflected wavelength of the photonic crystal structure may increase.

The first refractive index layer 11 includes a first polymer exhibiting a first refractive index n1, and the second refractive index layer 12 includes a second polymer exhibiting a second refractive index n2.

The first refractive index (n1) and the second refractive index (n2) may be different. The difference may be, for example, 0.01 to 0.5. Specifically, the difference may be 0.05 to 0.3, more specifically 0.1 to 0.2. The larger the difference between these refractive indices, the larger the optical band gap of the photonic crystal structure, so the difference between the refractive indices can be adjusted within the above-mentioned range to control light of the desired wavelength to be reflected, and the refractive index can be adjusted by changing the type of polymer, which will be described later. possible.

The first refractive index (n1) may be 1.3 to 1.6, and the second refractive index (n2) may be 1.51 to 1.8. In other words, the first refractive index layer 11 is a low refractive index layer, and the second refractive index layer 12 is a high refractive index layer, so that the photonic crystal structure 10 is a low refractive index layer / on the substrate 11. It may have a structure in which a high refractive index layer/low refractive index layer/high refractive index layer/low refractive index layer are sequentially stacked.

By adjusting the thickness within the above-mentioned range, the reflection wavelength of the photonic crystal structure can be adjusted. The thickness of each refractive index layer can be adjusted by varying the concentration of the polymer in the polymer dispersion composition or the coating speed of the dispersion composition.

In addition, Figure 1 shows only one photonic crystal structure 10 composed of a total of 5 layers, but the total number of stacks of the photonic crystal structures is not limited to this, and the anti-counterfeiting color conversion film includes a plurality of such photonic crystal structures.

Specifically, the total number of stacks of the first refractive index layer and the second refractive index layer may be 5 to 30 layers. In the case of a structure laminated in the above-mentioned range, sufficient interference of light reflected at the boundary of each layer may occur, so that the reflection intensity can be high enough to detect a color change due to an external stimulus. Additionally, the plurality of photonic crystal structures may each have a different total number of stacks of the first refractive index layer and the second refractive index layer.

The color conversion photonic crystal structure includes alternatingly stacked low refractive index layers and high refractive index layers.

The low refractive index layer contains a low refractive index polymer, and the high refractive index layer contains a high refractive index polymer. The refractive index can be determined by the polymer and inorganic salt contained in each refractive index layer.

The color conversion photonic crystal structure is humidity-sensitive, and its color can change due to changes in humidity. This may be due to a change in refractive index that occurs when the refractive index layer swells due to changes in humidity.

In the color conversion photonic crystal structure, the first refractive index layer may be a sensing layer that absorbs moisture. This may be due to using a polymer having higher hydrophilicity than the second polymer as the first polymer. To describe such a case in detail, when the photonic crystal structure is in contact with moisture, for example, when the photonic crystal structure is exposed to air containing moisture or is impregnated with liquid water, the first refractive index layer absorbs moisture and It swells, and the thickness changes accordingly. As a result, the reflection wavelength of the photonic crystal structure can be shifted. At this time, the shifted reflection wavelength (λ') is within the range of 380 nm to 760 nm, so the color change can be observed with the naked eye. The reflected wavelength (λ) and the shifted reflected wavelength (λ') can be measured with a device such as a reflectometer.

The first polymer included in the first refractive index layer (low refractive index layer), which has a relatively low refractive index, may include various monomer-derived structural units. For example, (meth)acrylate-based compounds, (meth)acrylamide-based compounds, vinyl group-containing aromatic compounds, dicarboxylic acids, xylylene, alkylene oxide, arylene oxide, and derivatives thereof. These can be applied individually or in combination of two or more types. For example, the first polymer may include one or two or more repeating units derived from the following monomers: methyl (meth)acrylate, ethyl (meth)acrylate, isobutyl (meth)acrylate, 1-phenylethyl (meth)acrylate, 2-phenylethyl (meth)acrylate, 1,2-diphenylethyl (meth)acrylate, phenyl (meth)acrylate, benzyl (meth)acrylate, m-nitro (meth)acrylate monomers such as benzyl (meth)acrylate, β-naphthyl (meth)acrylate, and benzoylphenyl (meth)acrylate; Methyl (meth)acrylamide, ethyl (meth)acrylamide, isobutyl (meth)acrylamide, 1-phenylethyl (meth)acrylamide, 2-phenylethyl (meth)acrylamide, phenyl (meth)acrylamide, benzyl (meth)acrylamide-based monomers such as (meth)acrylamide and benzoylphenyl (meth)acrylamide; Styrene-based monomers such as styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene, o-methoxystyrene, and 4-methoxy-2-methylstyrene; Aromatic monomers such as p-divinylbenzene, 2-vinylnaphthalene, vinyl carbazole, and vinyl fluorene; Terephthalic acid, isophthalic acid, 2,6-naphthalene dicarboxylic acid, 2,7-naphthalene dicarboxylic acid, 1,4-naphthalene dicarboxylic acid, 1,4-phenylene dioxyphenylenic acid, 1,3-phenylene dioxydiacetic acid, etc. dicarboxylic acid monomer; Xylylene-based monomers such as o-xylylene, m-xylylene, and p-xylylene; Alkylene oxide monomers such as ethylene oxide and propylene oxide; Phenylene oxide-based monomers such as phenylene oxide and 2,6-dimethyl-1,4-phenylene oxide can be used, and among these, those having high hydrophilicity and low refractive index are preferable.

Specifically, the first polymer may be a copolymer containing a repeating unit represented by the following formula (1):

[Formula 1]

(wherein R ₁ and R ₂ are each independently hydrogen or C1-3 alkyl,

R ₃ is represented by the following formula 2 or 3,

R ₄ is O or NH,

R ₅ is benzoylphenyl,

The benzoylphenyl is unsubstituted or substituted with 1 to 4 substituents each independently selected from the group consisting of hydroxy, halogen, nitro, C1-5 alkyl, and C1-5 alkoxy,

n and m are each independently integers of 1 or more,

n+m is 100 to 2,000.)

[Formula 2]

(Wherein, R ₆ is O, NH or ego,

R ₇ is H, OH, C1~10 alkyl, C1~10 aminoalkyl, C1~10 alkoxy or ego,

l is an integer from 1 to 20, and o is an integer from 1 to 10.)

[Formula 3]

(where p is an integer from 1 to 4).

Containing the copolymer represented by Formula 1 has a low refractive index, excellent chemical properties such as thermal stability, chemical resistance, and oxidation stability, and excellent transparency.

The copolymer containing a repeating unit represented by Formula 1 according to the present invention is randomly copolymerized with an acrylate or acrylamide monomer of Formula 2 or 3 and an acrylate or acrylamide monomer having a photoactive functional group (R ₅ ). It may be a random copolymer in which the repeating units between the square brackets of Formula 1 are randomly arranged.

The copolymer containing the repeating unit represented by Formula 1 according to the present invention may be a block copolymer in which blocks of repeating units between square brackets of Formula 1 are connected by covalent bonds. In addition, it may be an alternating copolymer in which the repeating units between the square brackets of Formula 1 are arranged in an alternating manner, or a graft copolymer in which any one repeating unit is combined in a branched form, but the arrangement of the repeating units is It is not limited.

The copolymer represented by Formula 1 according to the present invention may exhibit a refractive index of, for example, 1.3 to 1.6. When within the above-mentioned range, a photonic crystal structure that reflects light of a desired wavelength can be implemented due to a difference in refractive index from the polymer used in the second refractive index layer (high refractive index layer) described later.

In Formula 1, R ₁ and R ₂ may each independently be hydrogen or methyl. For example, R ₁ and R ₂ can be hydrogen.

In Formula 1, R ₅ may be unsubstituted or benzoylphenyl substituted with C1-3 alkyl. When R ₅ is benzoylphenyl, it may be advantageous in terms of ease of photocuring.

In Formula 1, n refers to the total number of repeating units derived from fluoroalkyl acrylamide-based monomers in the copolymer, and m is an acrylate or acrylamide-based monomer having a photoactive functional group (R ₅ ) in the copolymer. It means the total number of repeating units derived from.

At this time, the copolymer containing the repeating unit represented by Formula 1 may have an n:m molar ratio of 100:1 to 100:50 and a number average molecular weight of 10,000 to 100,000 g/mol. For example, the copolymer containing the repeating unit represented by Formula 1 may have an n:m molar ratio of 100:1 to 100:40, specifically 100:20 to 100:35. Also, for example, a copolymer containing a repeating unit represented by Formula 1 may have a number average molecular weight of 10,000 to 80,000 g/mol. Within the above range, it is possible to manufacture a copolymer that has a low refractive index and is easily photocurable.

Specifically, the copolymer containing a repeating unit represented by Formula 1 may be one of the copolymers containing a repeating unit represented by the following Formulas 1-1 to 1-10:

[Formula 1-1]

[Formula 1-2]

[Formula 1-3]

[Formula 1-4]

[Formula 1-5]

[Formula 1-6]

[Formula 1-7]

[Formula 1-8]

[Formula 1-9]

[Formula 1-10]

(wherein n, m and l are as described above).

The first refractive index layer may further include an inorganic salt.

Inorganic salts can be included in the first refractive index layer to lower the detection limit for humidity of the color conversion photonic crystal structure, improve reaction sensitivity, and increase reaction retention time.

The type of inorganic salt is not limited, but one with a low refractive index is preferable in terms of a large optical band gap. For example, chlorides such as lithium, magnesium, calcium, zinc, and aluminum, and halides such as bromide and iodide, specifically LiCl, NaCl, KCl, AlCl ₃ , MgCl ₂ , CaCl ₂ , LiTFSi, LiBr, NaBr, KBr. , AlBr ₃ , MgBr ₂ , CaBr ₂ , LiI, NaI, KI, AlI ₃ , MgI ₂ and CaI ₂ . The inorganic salt may be appropriately selected taking into account the refractive index within the range exemplified above and the degree of dispersion during formation of the refractive index layer. For example, the refractive index of LiCl is 1.662, NaCl is 1.5442, KCl is 1.4904, and CaCl ₂ is 1.442. The refractive index of the inorganic salt may be lower than the refractive index of the second refractive index layer.

The first refractive index layer may be formed by coating/drying a dispersion solution containing the first polymer and an inorganic salt.

The dispersion medium of the dispersion can be any material that can disperse the first polymer and the inorganic salt. For example, it may be ethanol, propanol, butanol, chlorobenzene, etc., but is not limited thereto.

The description of the first polymer and inorganic salt is the same as above.

The second polymer included in the second refractive index layer (high refractive index layer) with a relatively high refractive index may include various monomer-derived repeating units. For example, (meth)acrylate-based compounds, (meth)acrylamide-based compounds, vinyl group-containing aromatic compounds, dicarboxylic acids, xylylene, alkylene oxide, arylene oxide, and derivatives thereof. These can be applied individually or in combination of two or more types. For example, the second polymer may include one or two or more repeating units derived from the following monomers: methyl (meth)acrylate, ethyl (meth)acrylate, isobutyl (meth)acrylate, 1-phenylethyl (meth)acrylate, 2-phenylethyl (meth)acrylate, 1,2-diphenylethyl (meth)acrylate, phenyl (meth)acrylate, benzyl (meth)acrylate, m-nitro (meth)acrylate monomers such as benzyl (meth)acrylate, β-naphthyl (meth)acrylate, and benzoylphenyl (meth)acrylate; Methyl (meth)acrylamide, ethyl (meth)acrylamide, isobutyl (meth)acrylamide, 1-phenylethyl (meth)acrylamide, 2-phenylethyl (meth)acrylamide, phenyl (meth)acrylamide, benzyl (meth)acrylamide-based monomers such as (meth)acrylamide and benzoylphenyl (meth)acrylamide; Styrene-based monomers such as styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene, o-methoxystyrene, and 4-methoxy-2-methylstyrene; Aromatic monomers such as p-divinylbenzene, 2-vinylnaphthalene, vinyl carbazole, and vinyl fluorene; Terephthalic acid, isophthalic acid, 2,6-naphthalene dicarboxylic acid, 2,7-naphthalene dicarboxylic acid, 1,4-naphthalene dicarboxylic acid, 1,4-phenylene dioxyphenylenic acid, 1,3-phenylene dioxydiacetic acid, etc. dicarboxylic acid monomer; Xylylene-based monomers such as o-xylylene, m-xylylene, and p-xylylene; Alkylene oxide monomers such as ethylene oxide and propylene oxide; Phenylene oxide monomers such as phenylene oxide and 2,6-dimethyl-1,4-phenylene oxide. Among these, in terms of realizing a desirable refractive index difference and ease of photocuring, it may have a repeating unit derived from a styrene-based monomer and a repeating unit derived from one of (meth)acrylate and (meth)acrylamide.

Specifically, the second polymer used in the second refractive index layer may be a copolymer containing a repeating unit represented by the following formula 4 or 5:

[Formula 4]

[Formula 5]

(Wherein, R ₃ to R ₆ are each independently hydrogen or C1-3 alkyl,

A ₁ and A ₂ are each independently a C6-20 aromatic ring or a C2-20 heteroaromatic ring,

R ₁₁ to R ₁₃ are each independently hydroxy, cyano, nitro, amino, halogen, SO ₃ H, SO ₃ (C1-5 alkyl), C1-10 alkyl or C1-10 alkoxy, or are linked to each other and represent C4 Can form an aromatic ring of -12,

a1 to a3 are each independently an integer from 0 to 5,

L ₂ and L ₃ are each independently O or NH,

Y ₂ and Y ₃ are each independently benzoylphenyl,

Y ₂ and Y ₃ are unsubstituted or substituted with 1 to 4 substituents each independently selected from the group consisting of hydroxy, halogen, nitro, C1-5 alkyl, and C1-5 alkoxy,

n' and m' are each independently integers of 1 or more,

n'+m' is 100 to 2,000,

n" and m" are each independently integers of 1 or more,

n"+m" is from 100 to 2,000).

The copolymer containing the repeating unit represented by Formula 4 is an acrylate (L ₂ = O) or acrylamide (L ₂ = NH) monomer having a repeating unit derived from a styrene monomer and a photoactive functional group (Y ₂ ). It may refer to a polymer that simultaneously contains repeating units derived from. In addition, the copolymer represented by Formula 4 is derived from an acrylate (L ₃ = O) or acrylamide (L ₃ = NH)-based monomer having a repeating unit and a photoactive functional group (Y ₃ ) derived from a carbazole-based monomer. It may refer to a polymer that simultaneously contains repeated units.

When the copolymer containing the repeating unit represented by Formula 4 or 5 includes a repeating unit derived from a styrene-based monomer and a repeating unit derived from a carbazole-based monomer, the refractive index is high, making it possible to implement a high refractive index layer.

Moreover, the copolymer containing a repeating unit represented by Formula 4 or 5 further includes a repeating unit derived from an acrylate or acrylamide-based monomer having photoactive functional groups (Y ₂ and Y ₃ ), and is used as a separate photoinitiator. Alternatively, photocuring may be possible on its own without a crosslinking agent.

The copolymer containing the repeating unit represented by the above formula (4) is prepared by randomly copolymerizing a styrene-based monomer and an acrylate or acrylamide-based monomer having a photoactive functional group (Y ₂ ). It may be a random copolymer in which repeating units are randomly arranged.

Alternatively, the copolymer containing the repeating unit represented by Formula 4 may be a block copolymer in which blocks of repeating units between square brackets of Formula 4 are connected by covalent bonds. Alternatively, it may be an alternating copolymer in which the repeating units between the square brackets of Formula 4 are arranged in an alternating manner, or a graft copolymer in which any one repeating unit is combined in a branched form, but the arrangement of the repeating units The form is not limited.

Alternatively, the copolymer containing the repeating unit represented by Formula 5 may be a block copolymer in which blocks of repeating units between square brackets of Formula 5 are connected by covalent bonds. Alternatively, it may be an alternating copolymer in which the repeating units between the square brackets of Formula 5 are arranged in an alternating manner, or a graft copolymer in which any one repeating unit is combined in a branched form, but the arrangement of the repeating units The form is not limited.

A copolymer containing a repeating unit represented by Formula 4 or 5 may exhibit a refractive index of 1.51 to 1.8. When within the above-mentioned range, a color conversion photonic crystal structure that reflects light of a desired wavelength can be implemented due to a difference in refractive index with the polymer containing the repeating unit represented by Formula 1.

In Formula 4 or 5, R ₃ to R ₆ may each independently be hydrogen or methyl. For example, R ₃ to R ₆ may be hydrogen.

In Formula 5, A ₁ and A ₂ may each independently be a benzene ring or a naphthalene ring. For example, A ₁ and A ₂ may each independently be a benzene ring.

In Formula 4 or 5, R ₁₁ to R ₁₃ may each independently be hydrogen, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, or tert-butyl. At this time, a1 refers to the number of R ₁₁ and may be 0, 1, or 2. When a1 is 2 or more, 2 or more R ₁₁ may be the same or different from each other. a2 and a3 can also be understood with reference to the description of a1 and the structures of Formulas 4 and 5, and may be 0, 1, or 2.

In Formula 4 or 5, Y ₂ and Y ₃ may each independently be benzoylphenyl that is unsubstituted or substituted with C1-3 alkyl. When Y ₂ and Y ₃ are benzoylphenyl, it is advantageous in terms of ease of photocuring.

In Formula 4, n' refers to the total number of repeating units derived from styrene-based monomers in the copolymer, and m' refers to the number of repeating units derived from acrylate or acrylamide-based monomers having a photoactive functional group in the copolymer. It means total number.

The copolymer containing the repeating unit represented by Formula 4 according to the present invention may have an n':m' molar ratio of 100:1 to 100:50, for example, 100:30 to 100:50. Additionally, the copolymer containing the repeating unit represented by Formula 4 may have a number average molecular weight (Mn) of 10,000 to 100,000 g/mol, for example, 10,000 to 50,000 g/mol. Within the above range, it is possible to manufacture a copolymer that is easily photocurable while having a difference in refractive index within the above-mentioned range and a copolymer containing the repeating unit represented by Formula 1.

Specifically, the copolymer containing a repeating unit represented by Formula 4 according to the present invention may be a copolymer containing a repeating unit represented by the following Formula 4-1:

[Formula 4-1]

(In the formula, the definitions of n' and m' are as previously defined).

In Formula 5, n” refers to the total number of repeating units derived from carbazole-based monomers in the copolymer, and m” refers to repeating units derived from acrylate or acrylamide-based monomers having a photoactive functional group in the copolymer. means the total number of .

The copolymer containing the repeating unit represented by Formula 5 according to the present invention may have an n":m" molar ratio of 100:1 to 100:50, for example, 100:1 to 100:40. Additionally, the copolymer containing the repeating unit represented by Formula 5 may have a number average molecular weight (Mn) of 10,000 to 500,000 g/mol, for example, 10,000 to 350,000 g/mol. Within the above range, it is possible to manufacture a copolymer that is easily photocurable while having a difference in refractive index within the above-mentioned range and a copolymer containing the repeating unit represented by Formula 1.

Specifically, the copolymer containing a repeating unit represented by Formula 5 may be a copolymer containing a repeating unit represented by the following Formula 5-1 or 5-2:

[Formula 5-1]

[Formula 5-2]

(In the formula, the definitions of n” and m” are as previously defined).

The second refractive index may be higher than the refractive index of the inorganic salt. Specifically, the refractive index of the second polymer may be higher than that of the inorganic salt.

The second refractive index layer may be formed by coating/drying a dispersion containing a second polymer on the first refractive index layer.

The dispersion medium of the dispersion can be any material that can disperse the second polymer. For example, it may be ethanol, propanol, butanol, chlorobenzene, etc., but is not limited thereto.

The laminate of the present invention detects temperature changes and changes the color of the Zion pigment layer, thereby changing the color of the laminate. Additionally, when a change in humidity is added, the color of the color conversion photonic crystal structure changes, thereby changing the color of the laminate. And when the temperature changes again and the color of the Zion pigment layer returns to before the change, the color of the laminate changes again. Accordingly, various color changes can be realized according to changes in temperature and humidity.

Figure 9 is a photograph of an example of a laminate in which a color conversion photonic crystal structure is laminated on a Zion pigment layer whose color changes from white to black in response to temperature. When the background color (ion pigment layer) is white, the color of the color conversion photonic crystal structure appears yellow, magenta, and cyan due to increased humidity, but when the background color is black under the same conditions, it appears blue, green, yellow, orange, and red. You can see what it looks like. Specifically, referring to FIG. 13, when a black background is applied, color conversion occurs due to the reflected wavelength of the photonic crystal structure, and when a white background is applied, light is synthesized by wavelengths other than those reflected on the surface of the photonic crystal structure. You can see that the color conversion appears in color. In this way, depending on the color of the background (Zion pigment layer), whether or not light is reflected by the Zion pigment layer and the reflected wavelength change, and the color of the synthesized light that is visible to the user changes accordingly, and the color of the Zion pigment layer and the photonic crystal structure By selecting various colors, various color changes can be displayed.

Additionally, the present invention relates to an anti-counterfeiting film comprising the above-described laminate.

The photonic crystal structure may exhibit color conversion by shifting the reflection wavelength depending on changes in humidity. This may occur as the first or second refractive index layer absorbs moisture, changes the refractive index, and increases the thickness of the refractive index layer. .

Additionally, as the humidity of the photonic crystal structure increases, that is, as the moisture content increases, the reflection wavelength may shift to a longer wavelength. Accordingly, the shifted reflection wavelength (λ') of the photonic crystal structure may have a larger value than the reflection wavelength (λ) in the absence of external stimulation. Therefore, the color conversion film containing this shows color conversion when stimulated by high humidity compared to the case without external stimulation.

The anti-counterfeiting film of the present invention may include one or more of the photonic crystal structures described above. For example, the anti-counterfeiting film may include two or more, or 2 to 100, photonic crystal structures described above, but is not limited thereto. Any general film manufacturing method for manufacturing a film using the photonic crystal structure is possible, and the method is not limited.

The plurality of photonic crystal structures are each independently, the type of the above-described first and second polymers, the type of inorganic salt, the thickness of the first refractive index layer and the second refractive index layer, and/or the total stack of the first refractive index layer and the second refractive index layer. The numbers may be the same or different.

Additionally, the present invention relates to a color conversion sensor including the above laminate.

The color conversion sensor of the present invention may be a temperature and/or humidity sensor.

The color conversion sensor of the present invention has excellent sensitivity to temperature and humidity, and has a low detection limit, so it can exhibit excellent responsiveness even to low humidity. Additionally, the reaction duration is long and visibility is excellent.

Additionally, the present invention relates to a method for manufacturing the above laminate.

The method of the present invention includes forming a first refractive index layer comprising applying a first dispersion containing a first polymer on a Zion pigment layer; and forming a second refractive index layer including applying a second dispersion containing a second polymer on the first refractive index layer.

First, forming a first refractive index layer includes applying a first dispersion containing a first polymer.

The description of the first polymer and the first refractive index layer is the same as above.

The first dispersion contains a first polymer, and the dispersion medium used in the first dispersion can be any material that can disperse the first polymer. For example, it may be ethanol, propanol, butanol, etc., but is not limited thereto. no.

The content of the first polymer included in the first dispersion is not particularly limited. For example, the first polymer may be present in an amount of 0.01 to 5% by weight, 0.01 to 4% by weight, 0.1 to 5% by weight, 0.1 to 4% by weight, 0.1 to 3.5% by weight, 0.1 to 3% by weight, 0.5% by weight of the total weight of the first dispersion. It may be included in 5% by weight, 0.5 to 4% by weight, or 0.5 to 3% by weight.

The first dispersion may further include an inorganic salt.

For example, the inorganic salt is 1 to 4% by weight, 1 to 3% by weight, 1 to 2.5% by weight, 1.5 to 4% by weight, 1.5 to 3% by weight, 1.5 to 2.5% by weight, 2 to 2% by weight of the total weight of the first dispersion. It may be included at 2.5% by weight.

The content ratio of the first polymer and the inorganic salt is not particularly limited, for example, 1: 0.001 to 5, 1: 0.01 to 5, 1: 0.01 to 4, 1: 0.01 to 3, 1: 0.1 to 5, 1: 0.1. to 4, 1: may be 0.1 to 3, but is not limited thereto.

The first dispersion may be applied, for example, on the Zion pigment layer or on the second refractive index layer.

Methods for applying the first dispersion on the substrate or refractive index layer include spin coating, dip coating, roll coating, screen coating, spray coating, Examples include spin casting, flow coating, screen printing, ink jet, or drop casting, but are not limited thereto.

After applying the dispersion, the first refractive index layer can be formed by drying/curing the dispersion by a method known in the art.

Next, forming a second refractive index layer includes applying a second dispersion containing a second polymer on the first refractive index layer.

The description of the second polymer is the same as described above.

The second dispersion contains a second polymer, and any dispersion medium used in the second dispersion can be used as long as it can disperse the second polymer. For example, it may be ethanol, propanol, butanol, etc., but is limited thereto. It doesn't work.

The content of the second polymer included in the second dispersion is not particularly limited. For example, the second polymer may be present in an amount of 0.01 to 5% by weight, 0.01 to 4% by weight, 0.1 to 5% by weight, 0.1 to 4% by weight, 0.1 to 3.5% by weight, 0.1 to 3% by weight, 0.5% by weight of the total weight of the second dispersion. It may be included in 5% by weight, 0.5 to 4% by weight, or 0.5 to 3% by weight.

The method exemplified above may be used as a method of applying the second dispersion, but is not limited thereto.

If necessary, UV curing may be performed during curing, but is not limited thereto.

Hereinafter, the present invention will be described in detail with reference to examples.

Substance used

In the following production examples, the following materials were used. At this time, each material was used without a separate purification process.

- 4-Aminobenzophenone: A product from TCI (Tokyo chemical industries) with 98% purity was used.

- Triethylamine: A product from TCI (Tokyo chemical industry) with 99% purity was used.

- Dichloromethane: Burdick&jackson product with 99.9% purity was used.

- Acryloyl chloride: Merck product with 96% purity was used.

- Tetrahydrofuran: Burdick&jackson product with 99.99% purity was used.

- p-Methylstyrene: A product from Sigma-aldrich with 96% purity was used.

- Azobisisobutyronitrile: A product from JUNSEI with 98% purity was used.

- N-Isopropyl acrylamide: A product from TCI (Tokyo chemical industries) with 98% purity was used.

- N-Isopropylacrylamide: A product from TCI (Tokyo chemical industries) with 98% purity was used.

- Acrylic acid: 99% purity product from Sigma-aldrich was used.

- Polyethylene glycol methacrylate: average molecular weight Mn 500, product from Sigma-aldrich was used.

-2-Vinyl naphthalene: 95% purity product from Sigma-aldrich was used.

Monomers and Copolymers

The names and notations of the monomers and copolymers prepared in the following production examples are shown in Table 1 below.

division designation Mark Production example A N-(4-benzoylphenyl)acrylamide BPAA Production example B 4-benzoylphenyl acrylate BPA Manufacturing Example 1 poly(Vinylpyrrolidone)-co-poly(N-(benzoylphenyl)acrylamide) Poly(VP-BPAA) Production example 2 poly(Acrylic acid)-co- poly(N-(benzoylphenyl)acrylamide) Poly(AA-BPAA) Production example 3 poly(9-vinylcarbazole)-co-4-benzoylphenylacrylate Poly(VC-BPA) Production example 4 Poly(acrylic acid-co-benzophenone acrylate) Poly(AA-BPA) Production example 5 Poly(poly(ethylene glycol) methacrylate-co-benzophenone acrylate)) Poly(PEGMA-BPA) Production example 6 Poly(2-vinyl naphthalene-co-benzophenone acrylate) Poly(2VN-BPA)

Manufacturing example

Monomer synthesis

Preparation Example A: Preparation of BPAA

9.86 g of 4-aminobenzophenone, 15 mL of triethylamine, and 80 mL of dichloromethane were added to a 250 mL round flask, and the flask was placed in ice water. 4.06 mL of Acryloyl chloride was added and stirred for 12 hours. After the reaction was completed, the solvent was removed, and then dried in a vacuum oven to obtain N-(4-benzoylphenyl)acrylamide as a yellow solid.

Preparation Example B: Preparation of BPA

10 g of 4-hydroxybenzophenone, 20 mL of triethylamine, and 120 mL of dichloromethane were added to a 250 mL round flask, and the flask was placed in ice water. 4.92 mL of Acryloyl chloride was added and stirred for 12 hours. After completion of the reaction, the solvent was removed and dried in a vacuum oven to obtain N-(4-benzoylphenyl)acrylate as a yellow solid.

Copolymer synthesis

Preparation Example 1: Poly(VP-BPAA)

25 mL of vinyl pyrrolidone, 5 g of N-(4-benzoylphenyl)acrylamide, 0.1 g of AIBN, and 15 mL of 1,4-dioxane were added to a 50 mL schlenk flask and stirred with a magnetic bar to mix everything. The mixture was stirred in a 50°C oil bath for 4 hours. After completion of the reaction, the polymer was extracted and dried in a vacuum oven to obtain Poly(VP-BPAA) (n: m = 92: 8).

Preparation Example 2: Preparation of Poly(AA-BPAA)

25 mL of acrylic acid, 5 g of N-(4-benzoylphenyl)acrylamide, 0.1 g of AIBN, and 25 mL of 1,4-dioxane were added to a 50 mL schlenk flask and stirred with a magnetic bar to mix everything. The mixture was stirred in a 50°C oil bath for 3 hours. After completion of the reaction, the polymer was extracted and dried in a vacuum oven to obtain Poly(AA-BPAA) (n: m = 95:5).

Preparation Example 3: Preparation of Poly(VC-BPA)

3 g of 9-vinyl carbazole, 1 g of BPA prepared in Preparation Example B, and 0.1 g of Azobisisobutyronitrile were added to a 25 ml round flask and stirred. The reaction was carried out for 15 hours. After completion of the reaction, the polymer was extracted by filtering and then dried in a vacuum oven at room temperature to obtain Poly(VC-BPA) (n": m" = 90: 10).

Preparation Example 4: Preparation of Poly(AA-BPA)

25 mL of acrylic acid, 5 g of N-(4-benzoylphenyl)acrylate, 0.1 g of AIBN, and 25 mL of 1,4-dioxane were added to a 50 mL schlenk flask and stirred with a magnetic bar to mix everything. The mixture was stirred in a 70°C oil bath for 8 hours. After completion of the reaction, the polymer was extracted and dried in a vacuum oven to obtain Poly(AA-BPA) (n: m = 98:2).

Preparation Example 5: Preparation of Poly(PEGMA-BPA)

2.78 mL of poly(ethylene glycol) methacrylate, 0.031 g of N-(4-benzoylphenyl)acrylate, 0.002 g of AIBN, and 25 mL of DMF were added to a 9 mL Schlenk flask and stirred with a magnetic bar to mix everything. The mixture was stirred in a 70°C oil bath for 8 hours. After completion of the reaction, the polymer was extracted and dried in a vacuum oven to obtain Poly(PEGMA-BPA) (n: m = 96:4).

Preparation Example 6: Preparation of Poly(2VN-BPA)

5 g of 2-Vinyl naphthalene, 0.9 g of BPA prepared in step 1, and 0.01 g of azobisisobutyronitrile were added to a 25 ml round flask and then incubated at 80°C for 24 hours. Time reaction was carried out. After completion of the reaction, the polymer was extracted and dried in a vacuum oven at room temperature (25°C) to obtain the title compound Poly(2VN-BPA) (n: m = 90:10).

Experimental Example 1: Measurement of physical properties of copolymer

The specific physical properties of the copolymers prepared in Preparation Examples 1 to 6 were measured by the following method, and the results are shown in Table 2.

division Mn (g/mol) PDI BPA
content(%) BPAA content (%) refractive index Manufacturing Example 1 15,000 1.49 - 5.5 1.544 Production example 2 86,000 1.18 - 9.42 1.536 Production example 3 83,000 2.28 10 - 1.636 Production example 4 58,000 2.07 2 - 1.51 Production example 5 71,000 8.74 4 - 1.48 Production example 6 44,700 6.14 10 - 1.63

Mn (number average molecular weight) and PDI (molecular weight distribution): were measured using gel permeation chromatography (GPC) using polystyrene as a standard sample for calibration.

Tg (glass transition temperature): measured using a DSC (differential scanning calorimeter).

Content of BPAA structural unit: measured by NMR.

Refractive index: Measured by ellipsometer.

Comparative Example 1.

(1) Experimental method

Poly(AA-BPA) prepared in Preparation Example 4 was dissolved in propol at 2.0% by weight to prepare a low refractive index dispersion, and Poly(VC-BPA) prepared in Preparation Example 3 was dissolved in chlorobenzene at 2.5% by weight. A refractive index dispersion was prepared. The high refractive index dispersion was applied on a glass substrate at a speed of 2800 rpm using a spin coater, and then cured at 365 nm for 15 minutes to prepare a 120 nm thick high refractive index layer. The low refractive index dispersion was applied on the high refractive index layer at a speed of 2800 rpm using a spin coater and cured at 365 nm for 10 minutes to prepare a 100 nm thick low refractive index layer. By repeatedly stacking a high refractive index layer and a low refractive index layer on the low refractive index layer, a color conversion photonic crystal structure with a total of 10 refractive index layers was manufactured.

(2) Experiment results

When you blew on it, the color of the film changed in 4 seconds, and it took 4.5 seconds to return to its original state.

Example.

(1) Example 1

Poly(AA-BPA) prepared in Preparation Example 4 was dissolved in propanol at 2% by weight, and the inorganic salt LiCl was dissolved at 4% by weight to prepare a first dispersion (low refractive index dispersion), and the Poly(AA-BPA) prepared in Preparation Example 3 was dissolved at 2% by weight in propanol. (VC-BPA) was dissolved in chlorobenzene to a concentration of 2.0% to prepare a second dispersion (high refractive index dispersion). The second dispersion was applied on a glass substrate at a speed of 3000 rpm using a spin coater, and then cured at 365 nm for 15 minutes to prepare a second refractive index layer (high refractive index layer) with a thickness of 120 nm. The first dispersion was applied on the second refractive index layer at a speed of 3000 rpm using a spin coater and cured at 365 nm for 10 minutes to prepare a first refractive index layer with a thickness of 100 nm. By repeatedly stacking the second refractive index layer and the first refractive index layer on the first refractive index layer, a color conversion photonic crystal structure with a total of 10 refractive index layers was manufactured.

(2) Examples 2 to 25

In Example 1, the concentration of the low refractive polymer, type of inorganic salt, concentration of inorganic salt, low refractive dispersion medium, concentration of high refractive polymer, high refractive dispersion medium, low refractive index layer, and spin coating speed during production of the high refractive index layer shown in Table 3 below were used. It is the same except that Examples 1 and 2 were manufactured with a total of 4 refractive index layers, and Examples 3 and 17 were manufactured with a total of 10 refractive index layers, except that they were manufactured with a total of 8 refractive index layers.

Example low refractive index layer High refractive index layer spin coating Concentration of first polymer inorganic salt Concentration of mineral salts (%) dispersion medium dispersion medium Concentration of second polymer rpm One 2 LiCl 4 Propanol Chlorobenzene 2 3000 2 2 LiCl 4 Propanol 2 2300 3 2 LiCl 4 Propanol 2.5 2300 4 2 LiCl 0.5 butanol 2.5 2000 5 2 LiCl One Propanol 2.5 2500 6 2 LiCl 2 Propanol 2.5 1800 7 2 KCl 0.1 ethanol 2.5 2000 8 2 KCl 0.01 ethanol 2.5 2000 9 2 KCl 0.01 Propanol 2.5 2000 10 2 CaCl ₂ 0.5 ethanol 2.5 3500 11 2 CaCl ₂ 0.5 ethanol 2.5 3200 12 2 CaCl ₂ One ethanol 2.5 3200 13 2 CaCl ₂ 0.5 ethanol 2 2500 14 2 CaCl ₂ 3 Propanol 2.5 3800 15 2 CaCl ₂ 2 Propanol 2.5 3800 16 2 CaCl ₂ 3 Propanol 2.5 3800 17 2 CaCl ₂ 2 Propanol 2 3300 18 2 CaCl ₂ 2 Propanol 2 3800 19 1.5 CaCl ₂ 1.5 Propanol 2 2800 20 1.5 CaCl ₂ 0.1 Propanol 2 3000 21 1.5 CaCl ₂ 0.3 Propanol 2 3000 22 1.5 CaCl ₂ 0.5 Propanol 2 3000 23 1.5 CaCl ₂ 1.5 Propanol 2 3000 24 1.5 CaCl ₂ One Propanol 2 3000 25 1.5 CaCl ₂ One Propanol 2 3000

(3) Example 26

Poly(PEGMA-BPA) prepared in Preparation Example 5 was dissolved in propanol at 1.5% by weight, and the inorganic salt CaCl ₂ was dissolved at 1% by weight to prepare the first dispersion (low refractive index dispersion). Poly(VN-BPA) was dissolved in chlorobenzene to a concentration of 2.5% to prepare a second dispersion (high refractive index dispersion). The second dispersion was applied on a glass substrate at a speed of 3000 rpm using a spin coater, and then cured at 365 nm for 15 minutes to prepare a second refractive index layer (high refractive index layer) with a thickness of 120 nm. The first dispersion was applied on the second refractive index layer at a speed of 3000 rpm using a spin coater and cured at 365 nm for 10 minutes to prepare a first refractive index layer with a thickness of 100 nm. By repeatedly stacking the second refractive index layer and the first refractive index layer on the first refractive index layer, a color conversion photonic crystal structure with a total of 10 refractive index layers was manufactured.

(4) Manufacture of a laminate including a Zion pigment layer and a color conversion photonic crystal structure laminated thereon.

The composition shown in Table 4 below was used as the Zion pigment layer paint.

The Zion pigment layer paint was bar-coated to a thickness of 0.15 mm on the film to form a Zion pigment layer, which was then cured in an oven at 60°C. Thereafter, a color conversion photonic crystal structure was manufactured on the Zion pigment layer using the composition and method of Example 25.

Material name Usage (wt%) manufacturing company PU binder 30~40 Jogwang Paint solvent 30~50 Jogwang Paint Anti-settling agent 0.5~5 BYK Defoamer and leveling agent 0.5~5 Jogwang Paint Zion pigment 1~20 Camel chemical UVA additive 1~5 BASF Korea Co., Ltd.

Experiment example

1. Check coating properties and sensing ability

The coating properties and sensing capabilities of the color conversion photonic crystal structures of each example were confirmed. Coating properties were judged based on whether the coating was clean and transparent, and sensing ability was judged based on whether the reactivity was excellent and whether the reaction was maintained for a long time. The results are shown in Table 5 below.△

Example initial color PET substrate color used Coating properties reactivity Holding ability One - black △ O O 2 - black △ O O 3 - Transparency △ O O 4 Orange Transparency △ O O 5 purple Transparency △ O O 6 purple Transparency △ O O 7 Orange Transparency △ O O 8 Orange Transparency △ O O 9 green Transparency △ O △ 10 blue Transparency O O △ 11 blue Transparency O O △ 12 yellow Transparency O O O 13 green Transparency O O O 14 blue black △ O - 15 Red black O O O 16 blue black △ O O 17 Orange black O O O 18 Red black O O - 19 green black O O O 20 UV black O O O 21 UV black O O O 22 UV black O O O 23 green black O O O 24 purple black O O O 25 purple Transparency O O O 26 - black O O O

O: Excellent, △: Average, X: Poor, (-: Does not return to original color after reaction)

2. Check the change in reflected wavelength according to humidity

The change in reflection wavelength according to the change in humidity of the color conversion photonic crystal structure of Example 25 was confirmed.

Referring to Figure 10, it can be seen that the reflected wavelength changes as the relative humidity increases from 30% to 90%.

3. Check the color change of the laminate

The color change of the laminate produced in the above example according to temperature/humidity changes was confirmed.

Referring to FIG. 11, it can be seen that when the color of the Zion pigment layer is black or white under the same humidity conditions, the color of the color conversion photonic crystal structure appears different, and the color of the color conversion photonic crystal structure changes as humidity increases. You can also see that the colors of the laminates with different backgrounds look different.

And referring to Figure 12, it can be seen that when the color of the Zion pigment layer is different from white to black, the color of the color conversion photonic crystal structure appears different under the same humidity conditions.

Claims (13)

A laminate comprising a Zion pigment layer and a humidity-sensitive color conversion photonic crystal structure laminated on the Zion pigment layer.
The laminate according to claim 1, wherein the temperature pigment layer changes color at a temperature above room temperature but below body temperature.
The laminate according to claim 1, wherein the Zion pigment layer changes color from black to white or from white to black in response to temperature.
The laminate according to claim 1, wherein the color conversion photonic crystal structure includes alternating low refractive index layers and high refractive index layers, and the low refractive index layer is more hydrophilic than the high refractive index layer.
The laminate according to claim 4, wherein the low refractive index layer includes an inorganic salt.
The laminate according to claim 5, wherein the refractive index of the high refractive index layer is higher than the refractive index of the inorganic salt.
The laminate according to claim 1, wherein the polymer included in the low refractive index layer of the color conversion photonic crystal structure is a copolymer containing a repeating unit represented by the following formula (1):
[Formula 1]

(wherein R ₁ and R ₂ are each independently hydrogen or C1-3 alkyl,
R ₃ is represented by the following formula 2 or 3,
R ₄ is O or NH,
R ₅ is benzoylphenyl,
The benzoylphenyl is unsubstituted or substituted with 1 to 4 substituents each independently selected from the group consisting of hydroxy, halogen, nitro, C1-5 alkyl, and C1-5 alkoxy,
n and m are each independently integers of 1 or more,
n+m is 100 to 2,000.)
[Formula 2]

(Wherein, R ₆ is O, NH or ego,
R ₇ is H, OH, C1~10 alkyl, C1~10 aminoalkyl, C1~10 alkoxy or ego,
l is an integer from 1 to 20, and o is an integer from 1 to 10.)
[Formula 3]

(where p is an integer from 1 to 4).
The laminate according to claim 7, wherein the copolymer is one of copolymers containing repeating units represented by the following formulas 1-1 to 1-10.
[Formula 1-1]

[Formula 1-2]

[Formula 1-3]

[Formula 1-4]

[Formula 1-5]

[Formula 1-6]

[Formula 1-7]

[Formula 1-8]

[Formula 1-9]

[Formula 1-10]

(In the formula, n and m are each independently an integer of 1 or more,
n+m is 100 to 2,000,
l is an integer from 1 to 20).
The laminate according to claim 1, wherein the polymer included in the high refractive index layer of the color conversion photonic crystal structure is a copolymer containing a repeating unit represented by the following formula (4) or (5):
[Formula 4]

[Formula 5]

(Wherein, R ₃ to R ₆ are each independently hydrogen or C1-3 alkyl,
A ₁ and A ₂ are each independently a C6-20 aromatic ring or a C2-20 heteroaromatic ring,
R ₁₁ to R ₁₃ are each independently hydroxy, cyano, nitro, amino, halogen, SO ₃ H, SO ₃ (C1-5 alkyl), C1-10 alkyl or C1-10 alkoxy, or are linked to each other and represent C4 Can form an aromatic ring of -12,
a1 to a3 are each independently an integer from 0 to 5,
L ₂ and L ₃ are each independently O or NH,
Y ₂ and Y ₃ are each independently benzoylphenyl,
Y ₂ and Y ₃ are unsubstituted or substituted with 1 to 4 substituents each independently selected from the group consisting of hydroxy, halogen, nitro, C1-5 alkyl, and C1-5 alkoxy,
n' and m' are each independently integers of 1 or more,
n'+m' is 100 to 2,000,
n" and m" are each independently integers of 1 or more,
n"+m" is from 100 to 2,000).
The laminate according to claim 9, wherein the copolymer is a copolymer containing a repeating unit represented by the following formula 5-1 or 5-2.
[Formula 5-1]

[Formula 5-2]

(In the formula, n" and m" are each independently an integer of 1 or more, and n"+m" is 100 to 2,000.)
The method of claim 5, wherein the inorganic salt is LiCl, NaCl, KCl, AlCl ₃ , MgCl ₂ , CaCl ₂ , LiTFSi, LiBr, NaBr, KBr, AlBr ₃ , MgBr ₂ , CaBr ₂ , LiI, NaI, KI, AlI ₃ , A laminate containing at least one selected from the group consisting of MgI ₂ and CaI ₂ .
A color conversion sensor comprising the laminate of any one of claims 1 to 11.
An anti-counterfeiting film comprising the laminate of any one of claims 1 to 11.