WO2023176857A1

WO2023176857A1 - Laminate, decorative film, article, decorative panel, and display device

Info

Publication number: WO2023176857A1
Application number: PCT/JP2023/009955
Authority: WO
Inventors: 寛稲田; 亮司後藤
Original assignee: 富士フイルム株式会社
Priority date: 2022-03-15
Filing date: 2023-03-14
Publication date: 2023-09-21

Abstract

This laminate has: a dichroic dye layer containing a dichroic dye; and a layer that exhibits a structural color. The dichroic dye layer has an absorption peak wavelength A in a wavelength range of 400-700 nm. The layer that exhibits a structural color has a reflection peak wavelength B in the wavelength range of 400-700 nm. The laminate has a wavelength bandwidth in which an absorption peak at the wavelength A and a reflection peak at the wavelength B overlap at least partially, when the laminate is viewed from the dichroic dye layer side at a viewing angle of -90° to 90°. This decorative film, article, decorative panel, and display device employ the laminate.

Description

Laminates, decorative films, articles, decorative panels, and display devices

The present disclosure relates to a laminate, a decorative film, an article, a decorative panel, and a display device.

As a conventional laminate, those described in Japanese Patent No. 6647182 or Japanese Unexamined Patent Publication No. 2018-045715 are known.
Japanese Patent No. 6647182 discloses a laminate including a dichroic dye layer in which a dichroic dye is oriented and fixed, and a reflective layer disposed on the dichroic dye layer, A laminate is described in which the dichroic dye layer is a layer in which the dichroic dye is fixed in a vertically aligned state, and the reflective layer is a layer in which a cholesteric liquid crystal phase is fixed.
JP 2018-045715A discloses a laminated layer including a dichroic dye layer in which a dichroic dye is oriented and fixed, and an absorbing layer or a reflective layer disposed on the dichroic dye layer. body is described.

As a conventional optical film, one described in JP-A-2015-102811 is known.
JP-A-2015-102811 discloses that a self-luminous type light source that emits red light, green light, and blue light is provided on the light emitting surface side of the light source, and that An optical film that absorbs at least part of the light, and in which at least one of the directions parallel to the surface of the optical film is tilted by a predetermined angle with respect to the normal direction of the surface. The transmittance of the blue light is lower than at least the transmittance of the green light in the inclined direction, or the transmittance of the red light in the normal direction is lower than the transmittance of the green light. An optical film is described that is characterized by low

As a conventional display device, one described in Japanese Unexamined Patent Publication No. 2018-147761 is known.
JP 2018-147761 A discloses a substrate having a light emitting layer, a circularly polarizing plate and a retardation layer disposed on the display surface side of the substrate, and the retardation layer has a light absorption rate. Display devices are described that include dichroic dyes with their major axes oriented perpendicular to the display surface.

A problem to be solved by an embodiment of the present disclosure is to provide a laminate with low viewing angle dependence.
A problem to be solved by other embodiments of the present disclosure is to provide a decorative film, an article, a decorative panel, and a display device using the above-mentioned laminate.

Means for solving the above problems include the following aspects.
<1> A dichroic dye layer containing a dichroic dye and a layer expressing a structural color, the dichroic dye layer having an absorption peak wavelength A in a wavelength range of 400 nm or more and 700 nm or less. , the layer expressing the structural color has a reflection peak wavelength B in a wavelength range of 400 nm or more and 700 nm or less, and when viewed from the dichroic dye layer side at a viewing angle of -90° to 90°, the above wavelength A laminate having a wavelength band in which the absorption peak at wavelength A and the reflection peak at wavelength B at least partially overlap each other.
<2> The laminate according to <1>, wherein the layer expressing the structural color is a layer made of a dielectric multilayer film or a cholesteric liquid crystal layer.
<3> The laminate according to <1> or <2>, wherein the angle θ between the transmittance center axis of the dichroic dye layer and the normal direction of the laminate is 0° to 45°.
<4> The laminate according to any one of <1> to <3>, wherein the layer expressing the structural color has two or more reflective regions having different selective reflection wavelengths.
<5> The laminate according to any one of <1> to <4>, wherein the dichroic dye layer is a layer formed by polymerizing at least a liquid crystal compound having a polymerizable group.
<6> The laminate according to any one of <1> to <5>, wherein the layer expressing the structural color is a cholesteric liquid crystal layer.
<7> The laminate according to <6>, wherein the cholesteric liquid crystal layer includes a chiral agent having a site that isomerizes upon irradiation with light.
<8> Expresses a structural color, having a dichroic dye layer containing a dichroic dye (preferably the dichroic dye is oriented and fixed) and two or more reflective regions with different selective reflection wavelengths. A laminate having a layer.
<9> The laminate according to <8>, wherein the angle θ between the central transmittance axis of the dichroic dye layer and the normal direction of the laminate is 0° to 45°.
<10> A decorative film comprising the laminate according to any one of <1> to <9>.
<11> An article comprising the laminate according to any one of <1> to <9>.
<12> A decorative panel comprising the decorative film according to <10>.
<13> A display device including the decorative panel according to <12>.

According to an embodiment of the present disclosure, a laminate with low viewing angle dependence can be provided.
According to other embodiments of the present disclosure, it is possible to provide a decorative film, an article, a decorative panel, and a display device using the above-mentioned laminate.

FIG. 1 is a schematic cross-sectional view showing an example of a decorative film according to the present disclosure. FIG. 2 is a diagram for explaining the overlap between the wavelength band of the half-width of the absorption peak of the dichroic dye layer and the wavelength band of the half-width of the reflection peak of the layer expressing structural color.

Hereinafter, the laminate according to the present disclosure will be explained. However, the present disclosure is not limited to the following embodiments, and can be implemented with appropriate modifications within the scope of the purpose of the present disclosure. When describing embodiments of the present disclosure with reference to the drawings, descriptions of overlapping components and symbols may be omitted. Components indicated using the same reference numerals in the drawings mean the same components. The proportions of dimensions in the drawings do not necessarily represent the proportions of actual dimensions.

Regarding the notation of a group (atomic group) in the present disclosure, the notation that does not indicate substituted or unsubstituted includes not having a substituent as well as having a substituent. For example, the term "alkyl group" includes not only an alkyl group without a substituent (unsubstituted alkyl group) but also an alkyl group having a substituent (substituted alkyl group).
"Light" in this disclosure means actinic rays or radiation.
"Active rays" or "radiation" in the present disclosure include, for example, the bright line spectrum of a mercury lamp, far ultraviolet rays typified by excimer lasers, extreme ultraviolet (EUV) light, X-rays, and electron beams (EB). Beam) etc.
Unless otherwise specified, "exposure" in this disclosure refers not only to exposure to the bright line spectrum of a mercury lamp, far ultraviolet rays typified by excimer lasers, extreme ultraviolet rays, X-rays, and EUV light, but also to electron beams and ion beams. This also includes exposure to particle beams such as.
In the present disclosure, "~" is used to include the numerical values described before and after it as a lower limit value and an upper limit value.

In this disclosure, (meth)acrylate refers to acrylate and methacrylate, and (meth)acrylic refers to acrylic and methacrylic.
In the present disclosure, the weight average molecular weight (Mw) of the resin component, the number average molecular weight (Mn) of the resin component, and the degree of dispersion (also referred to as molecular weight distribution) (Mw/Mn) of the resin component are measured using a GPC (Gel Permeation Chromatography) apparatus. GPC measurement using (HLC-8120GPC manufactured by Tosoh Corporation) (solvent: tetrahydrofuran, flow rate (sample injection amount): 10 μL, column: TSK gel Multipore HXL-M manufactured by Tosoh Corporation, column temperature: 40°C, flow rate: 1 .0 mL/min, detector: Defined as a polystyrene equivalent value determined by a differential refractive index detector (Refractive Index Detector).

In the present disclosure, if there are multiple substances corresponding to each component in the composition, unless otherwise specified, the amount of each component in the composition means the total amount of the multiple substances present in the composition. do.
In the present disclosure, the term "step" is used not only to refer to an independent process but also to include any process that achieves its intended purpose even if it cannot be clearly distinguished from other processes. .
In the present disclosure, "total solid content" refers to the total mass of the components excluding the solvent from the entire composition of the composition. Further, the "solid content" refers to the components excluding the solvent from the entire composition of the composition, and may be solid or liquid at 25° C., for example.
In the present disclosure, "mass %" and "weight %" have the same meaning, and "mass parts" and "weight parts" have the same meaning.
Furthermore, in the present disclosure, a combination of two or more preferred embodiments is a more preferred embodiment.

(laminate)
A first embodiment of the laminate according to the present disclosure has a dichroic dye layer containing a dichroic dye and a layer expressing a structural color, and the dichroic dye layer has a wavelength of 400 nm or more and 700 nm. The layer expressing the structural color has an absorption peak wavelength A in the following region, has a reflection peak wavelength B in a wavelength range of 400 nm or more and 700 nm or less, and has a viewing angle of −90° from the dichroic dye layer side. When viewed at an angle of ~90°, the absorption peak at the wavelength A and the reflection peak at the wavelength B have a wavelength band in which at least a portion thereof overlaps with each other.
A second embodiment of the laminate according to the present disclosure includes a dichroic dye layer containing a dichroic dye and a layer expressing a structural color, which has two or more reflective regions with different selective reflection wavelengths.

In this specification, unless otherwise specified, when the term "laminate according to the present disclosure" or "laminate" is used, both the first embodiment and the second embodiment are described.

Conventional laminates that have layers that express structural colors can be seen in color based on the principle of Bragg reflection, so when viewed from an angle, the problem may arise that the color has a viewing angle dependency that appears to be short-wave shifted. there were.
As a result of detailed studies by the present inventors, the present inventors have found that by adopting the above aspect, a laminate with low viewing angle dependence can be obtained.
When dichroic pigments are dispersed and oriented in an anisotropic medium, they appear colored when viewed from a certain direction, and appear colored in another color or almost colorless when viewed from a direction perpendicular to the above-mentioned direction. It is a pigment.
The laminate includes a dichroic dye layer having an absorption peak wavelength A in a wavelength range of 400 nm to 700 nm, and a layer expressing a structural color having a reflection peak wavelength B in a wavelength range of 400 nm to 700 nm, When viewed from the dichroic dye layer side at -90° to 90° (0° is when viewed from the normal direction of the dichroic dye layer), the absorption peak at the wavelength A and the absorption peak at the wavelength B A structure having a wavelength band in which the reflection peaks at least partially overlap with each other, or a dichroic dye layer in which a dichroic dye is oriented and fixed, and two or more reflection regions having different selective reflection wavelengths. Since the dichroic dye layer has a layer that expresses color, the change in absorption amount depending on the viewing angle by the dichroic dye layer suppresses or offsets the change in color depending on the viewing angle due to the layer that expresses structural color, and improves the visual field. It is estimated that a laminate with small angular dependence can be obtained.

[Relationship between absorption peak wavelength A and reflection peak wavelength B]
In a first embodiment of the laminate according to the present disclosure, the dichroic dye layer has an absorption peak wavelength A in a wavelength range of 400 nm or more and 700 nm or less, and the layer expressing the structural color has a wavelength of 400 nm or more. It has a reflection peak wavelength B in a region of 700 nm or less, and when viewed from -90° to 90° from the dichroic dye layer side, the absorption peak at the wavelength A and the reflection peak at the wavelength B are different from each other. They have wavelength bands that at least partially overlap.

"Absorption peak wavelength A in the wavelength range of 400 nm or more and 700 nm or less" is the peak wavelength in the absorption waveform measured from at least one of the viewing angles between -90° and 90°; It is preferably the peak wavelength in the absorption waveform measured from at least one viewing angle of -30° or 30° to 90°, and the peak wavelength is preferably measured at a viewing angle of -80° to -45° or 45° to 80°. More preferably, the wavelength is the peak wavelength in the absorption waveform.
"Reflection peak wavelength B in the wavelength range from 400 nm to 700 nm" is the peak wavelength in the reflected waveform measured from at least one of the viewing angles of -90° to 90°; It is preferably the peak wavelength in the reflected waveform measured from at least one viewing angle of -30° or 30° to 90°, and measured at a viewing angle of -80° to -45° or 45° to 80°. More preferably, the wavelength is the peak wavelength of the reflected waveform.

Note that "having wavelength bands that at least partially overlap with each other" refers to wavelength bands that overlap at least partially at an angle when viewed from the dichroic dye layer side at -90° to 90°. The absorption peak wavelength A and the reflection peak wavelength B do not need to be the same and may be different, and the entire wavelength band of the absorption peak at the absorption peak wavelength A and the reflection peak wavelength B It is not necessary that the entire wavelength band of the reflection peak overlaps, but it is sufficient that a part of the wavelength band overlaps. For example, as shown in FIG. 2, there is a wavelength band B that is the half-width of the absorption peak of the dichroic dye layer at a viewing angle of 55°, and a wavelength that is the half-width of the reflection peak of the layer that expresses structural color at the viewing angle of 55°. It is preferable that the wavelength band C overlaps with the band A.

Further, in a second embodiment of the laminate according to the present disclosure, from the viewpoint of reducing viewing angle dependence, the dichroic dye layer has an absorption peak wavelength A in a wavelength range of 400 nm or more and 700 nm or less, The layer expressing the structural color has a reflection peak wavelength B in a wavelength range of 400 nm or more and 700 nm or less, and when viewed from the dichroic dye layer side at -90° to 90°, the absorption at the wavelength A It is preferable that the peak and the reflection peak at wavelength B have wavelength bands that at least partially overlap with each other.

Further, from the viewpoint of reducing viewing angle dependence, the laminate according to the present disclosure has the above wavelength when viewed from the dichroic dye layer side at a viewing angle of -80° to -45° or 45 to 80°. It is preferable that the absorption peak at wavelength A and the reflection peak at wavelength B have wavelength bands that at least partially overlap with each other. With the above aspect, it is possible to reduce the hue difference especially when viewed from an oblique direction.
Note that when viewed from the dichroic dye layer side at a viewing angle of 0°, it is viewed from the normal direction of the dichroic dye layer (thickness direction of the dichroic dye layer).

The absorption peak in the present disclosure is measured by measuring the dichroic dye layer to be measured or the layer expressing a structural color at room temperature (23°C) in an air atmosphere using an automatic absolute reflectance measuring unit ARMN-735 and a spectrophotometer V. The absorbance at 55° is measured using -670EX (manufactured by JASCO Corporation), and the transmittance is calculated from the obtained value. The absorption peak wavelength is the wavelength (nm) at which the light intensity is minimum.

[Dichroic dye layer]
A first embodiment of the laminate according to the present disclosure has a dichroic dye layer containing a dichroic dye, and from the viewpoint of reducing viewing angle dependence, the dichroic dye layer has a dichroic dye layer. A layer in which the dye is oriented and fixed is preferable.
A second embodiment of the laminate according to the present disclosure has a dichroic dye layer containing a dichroic dye, and from the viewpoint of reducing viewing angle dependence, the dichroic dye layer has a dichroic dye layer. A layer in which the dye is oriented and fixed is preferable.

Here, the dichroic dye is a dye that exhibits anisotropy in light absorption, and means a dye that has the property that the color of transmitted light differs depending on the molecular axis direction of the dye.

In the laminate according to the present disclosure, the angle θ between the transmittance center axis of the dichroic dye layer and the normal direction of the laminate is set from the viewpoint of reducing viewing angle dependence especially when viewed from an oblique direction. , preferably 0° to 45°, more preferably 0° to 20°, even more preferably 0° to 10°, particularly preferably 0° to 5°.
Note that the transmittance central axis of the dichroic dye layer refers to the angular direction in which the absorption of the dichroic dye layer is the smallest.
Further, in the laminate according to the present disclosure, from the viewpoint of reducing viewing angle dependence particularly when viewed from an oblique direction, in the dichroic dye layer, the thickness direction of the dichroic dye layer and the two colors are The angle formed with the orientation direction of the sexual dye is preferably 0° to 20°, more preferably 0° to 10°, particularly preferably 0° to 5°.
In addition, when the dichroic dye layer is a layer in which the dichroic dye is oriented and fixed, the angle θ between the transmittance center axis of the dichroic dye layer and the normal direction of the laminate. The angle formed by the thickness direction of the dichroic dye layer and the orientation direction of the dichroic dye means the same angle.

<Dichroic dye>
The dichroic dye layer in the laminate according to the present disclosure contains a dichroic dye.
The dichroic dyes mentioned above are not particularly limited, but include, for example, acridine dyes, azine dyes, azomethine dyes, oxazine dyes, cyanine dyes, merocyanine dyes, squarylium dyes, naphthalene dyes, azo dyes, anthraquinone dyes, benzotriazole dyes, and benzophenone. Dyes, pyrazoline dyes, diphenylpolyene dyes, binaphthylpolyene dyes, stilbene dyes, benzothiazole dyes, thienothiazole dyes, benzimidazole dyes, coumarin dyes, nitrodiphenylamine dyes, polymethine dyes, naphthoquinone dyes, perylene dyes, quinophthalone dyes, stilbene dyes, Examples include indigo dyes.

Among these, dichroic dyes having a rod-shaped molecular shape (hereinafter also referred to as "rod-shaped dichroic dyes") are preferable, and specifically, azo dyes or anthraquinone dyes are more preferable. .

Specifically, preferred examples of the azo dye include those represented by the following formula (1) (hereinafter referred to as "azo dye (1)").

In the above formula (1), n is an integer of 1 to 4, and Ar ₁ and Ar ₃ each independently represent a group selected from the following group.

Moreover, in the above formula (1), Ar ₂ represents a group selected from the following group, and when n is 2 or more, Ar ₂ may be the same or different from each other.

In the above groups, A ₁ and A ₂ each independently represent a group selected from the group below.

In the formula, m is an integer from 0 to 10, and when there are two m's in the same group, the two m's may be the same or different from each other.

The positional isomerism of the substituents on both sides of the azo group of the azo dye (1) is preferably trans.
Examples of the azo dye (1) include compounds represented by the following formulas (1-1) to (1-58). In the following formulas (1-1) to (1-58), the positional isomerism of the substituents on both sides of the azo group is preferably trans.

Further, the dichroic dye preferably has a polymerizable group. For example, the polymerizable group is preferably an acrylic group, a methacryl group, a vinyl group, a vinyloxy group, an epoxy group, or an oxetanyl group. From the viewpoint of reactivity, an acrylic group, an epoxy group, or an oxetanyl group is particularly preferred.

Specific examples of dichroic dyes having a polymerizable group include the following compounds.

As the anthraquinone dye, a compound represented by formula (1-59) is preferred.

In the formula, R ¹ to R ⁸ each independently represent a hydrogen atom, -R _x , -NH ₂ , -NHR _x , -NR _x 2, -SR _x or a halogen atom, and R _x has 1 to 1 carbon atoms. 4 alkyl group or an aryl group having 6 to 12 carbon atoms.

The dichroic dyes may be contained alone or in combination of two or more.
The content of the dichroic dye is preferably 0.5% to 50% by mass, and 1% to 30% by mass, based on the total mass of the dichroic dye layer, from the viewpoint of reducing viewing angle dependence. It is more preferably 2% by mass to 20% by mass.

The dichroic dye layer contains the above-mentioned dichroic dye (especially rod-shaped dichroic dye) and a polymerizable group because it can further increase the change in hue when viewed from the front and from an oblique direction. It is preferable that the layer is formed by polymerizing at least a liquid crystal compound, and it is more preferable that the dichroic dye and the liquid crystal compound are both fixed in an oriented state.
Preferred examples of the liquid crystal compound include rod-like liquid crystal compounds.

<Rod-shaped liquid crystal compound>
Examples of rod-like liquid crystal compounds include azomethines, azoxys, cyanobiphenyls, cyanophenyl esters, benzoic acid esters, cyclohexanecarboxylic acid phenyl esters, cyanophenylcyclohexanes, cyano-substituted phenylpyrimidines, and alkoxy-substituted phenylpyrimidines. , phenyldioxanes, tolans and alkenylcyclohexylbenzonitrile are preferably used.

The polymerizable group contained in the rod-like liquid crystal compound includes an ethylenically unsaturated group, an alkynyl group, an epoxy group, and an aziridinyl group, with an ethylenically unsaturated group or an alkynyl group being preferred, and an ethylenically unsaturated group being particularly preferred. preferable.
The polymerizable group can be introduced into the molecules of the liquid crystal compound by various methods. The number of polymerizable groups that the liquid crystal compound has is preferably 1 to 6, more preferably 1 to 3.
As a rod-shaped liquid crystal compound having a polymerizable group, Makromol. Chem. , vol. 190, p. 2255 (1989), Advanced Materials vol. 5, p. 107 (1993), US Pat. No. 4,683,327, US Pat. No. 5,622,648, US Pat. , WO 95/24455, WO 97/00600, WO 98/23580, WO 98/52905, JP 1-272551, JP 6-16616, PT. Claim 1 of JP-A No. 7-110469, JP-A No. 11-80081, and Japanese Patent Publication No. 11-513019, and paragraphs 0026 to 0098 of JP-A No. 2001-328973 and JP-A No. 2005-289980 Compounds etc. can be used.

One type of rod-like liquid crystal compound may be used alone, or two or more types may be used in combination.
The content of the rod-like liquid crystal compound or its cured product is preferably 5% by mass to 99% by mass, and 10% by mass to 10% by mass, based on the total amount of the dichroic dye layer, from the viewpoint of reducing viewing angle dependence. It is more preferably 95% by mass, and particularly preferably 20% by mass to 90% by mass.

<Polymerization initiator>
The composition for forming a dichroic dye layer used when forming the dichroic dye layer preferably contains a polymerization initiator.
The polymerization initiator used is preferably a photopolymerization initiator that can initiate a polymerization reaction by irradiation with ultraviolet rays.
Examples of photopolymerization initiators include α-carbonyl compounds (described in U.S. Pat. Nos. 2,367,661 and 2,367,670), acyloin ether (described in U.S. Pat. No. 2,448,828), and α-hydrocarbon substituted aromatics. group acyloin compounds (described in U.S. Pat. No. 2,722,512), polynuclear quinone compounds (described in U.S. Pat. 3549367), acridine and phenazine compounds (described in JP-A-60-105667, US Pat. No. 4,239,850), oxadiazole compounds (described in US Pat. No. 4,212,970), acylphosphines Oxide compounds (described in Japanese Patent Publication No. 63-40799, Japanese Patent Publication No. 5-29234, Japanese Patent Application Laid-Open No. 10-95788, and Japanese Patent Application Publication No. 10-29997) can be mentioned.

The composition for forming a dichroic dye layer may contain one or more types of polymerization initiators.
The content of the polymerization initiator is from the viewpoint of curability and strength, and the ratio of the total amount of the polymerization initiator to the total solid content of the composition for forming a dichroic dye layer is 0.05% by mass to 10% by mass. %, more preferably 0.05% by mass to 5% by mass or less, even more preferably 0.1% to 2% by mass, and 0.2% to 1% by mass. It is particularly preferable that there be.

<Binder resin>
The dichroic dye layer may contain a binder resin from the viewpoints of strength, scratch resistance, and suitability for molding. The type of binder resin is not particularly limited. From the viewpoint of obtaining a desired color, the binder resin is preferably a transparent resin, and specifically, a resin having a total light transmittance of 80% or more is preferable. The total light transmittance can be measured with a spectrophotometer (eg, spectrophotometer "UV-2100" manufactured by Shimadzu Corporation).

Examples of the binder resin include cellulose resin, acrylic resin, silicone resin, polyester, polyurethane, and polyolefin. The binder resin may be a homopolymer or a copolymer.
Among these, cellulose resin is preferred, and cellulose acetate is more preferred.

One type of binder resin may be used alone, or two or more types may be used in combination.
The content of the binder resin is preferably 5% by mass to 95% by mass, and 10% by mass to 90% by mass, based on the total amount of the dichroic dye layer, from the viewpoints of strength, scratch resistance, and moldability. It is more preferable that the amount is 20% by mass to 60% by mass.

<Polymerizable compound>
The dichroic dye layer may contain a polymerizable compound from the viewpoints of strength, scratch resistance, and suitability for molding.
The polymerizable compound is not particularly limited, and known polymerizable compounds can be used. Among these, ethylenically unsaturated compounds are preferred, and (meth)acrylate compounds are more preferred.
Further, the polymerizable compound may be a monofunctional polymerizable compound or a polyfunctional polymerizable compound. Preferred examples of the polyfunctional polymerizable compound include crosslinking agents described below.

One type of polymerizable compound may be used alone, or two or more types may be used in combination.
The content of the cured product of the polymerizable compound is preferably 5% by mass to 95% by mass, and 10% by mass, based on the total amount of the dichroic dye layer, from the viewpoints of strength, scratch resistance, and molding processability. It is more preferably 90% by mass, and particularly preferably 20% by mass to 60% by mass.

<Solvent>
The composition for forming a dichroic dye layer used when forming the dichroic dye layer preferably contains a solvent from the viewpoint of workability in forming the dichroic dye layer.
Specifically, examples of the solvent include ketones (e.g., acetone, 2-butanone, methyl isobutyl ketone, cyclohexanone, etc.), ethers (e.g., dioxane, tetrahydrofuran, etc.), aliphatic hydrocarbons (e.g., hexane, etc.). ), alicyclic hydrocarbons (e.g., cyclohexane, etc.), aromatic hydrocarbons (e.g., toluene, xylene, trimethylbenzene, etc.), halogenated carbons (e.g., dichloromethane, dichloroethane, dichlorobenzene, chlorotoluene, etc.) ), esters (e.g. methyl acetate, ethyl acetate, butyl acetate, etc.), water, alcohols (e.g. ethanol, isopropanol, butanol, cyclohexanol, etc.), cellosolves (e.g. methyl cellosolve, ethyl cellosolve, etc.), cellosolve Examples include acetates, sulfoxides (e.g., dimethyl sulfoxide), amides (e.g., dimethylformamide, dimethylacetamide, etc.), and these may be used alone or in combination of two or more. .

Further, the dichroic dye layer may contain additives other than those mentioned above.
Examples of the additive include known additives, such as alignment agents and surfactants described below.

<Method for forming dichroic dye layer>
The method for forming the dichroic dye layer includes, for example, using a composition for forming a dichroic dye layer containing the dichroic dye described above, an arbitrary rod-like liquid crystal compound, a polymerization initiator, a solvent, and the like. , a method of obtaining a desired orientation state and then immobilizing it by polymerization.
Here, polymerization conditions are not particularly limited, but in polymerization by light irradiation, it is preferable to use ultraviolet rays. The irradiation amount is preferably 10 mJ/cm ² to 50 J/cm ² , more preferably 20 mJ/cm ² to 5 J/cm ² , even more preferably 30 mJ/cm ² to 3 J/cm ² . , 50 mJ/cm ² to 1,000 mJ/cm ² is particularly preferred.
Moreover, in order to promote the polymerization reaction, it may be carried out under heating conditions.
Note that, in the present disclosure, the dichroic dye layer can be formed on any base material in the laminate according to the present disclosure, which will be described later.

The thickness of the dichroic dye layer is not particularly limited, but from the viewpoint of reducing viewing angle dependence, it is preferably 0.05 μm to 10 μm, more preferably 0.1 μm to 8 μm, and 0.05 μm to 10 μm, more preferably 0.1 μm to 8 μm. It is more preferably 5 μm to 5 μm, and particularly preferably 1 μm to 3 μm.
Note that the thickness of each layer can be measured by observing a cross section of each layer with a scanning electron microscope (SEM).

[Layer that expresses structural color]
A first embodiment of the laminate according to the present disclosure has a layer that exhibits a structural color, and from the viewpoint of reducing visibility and viewing angle dependence, two or more reflective regions with different selective reflection wavelengths are provided. It is preferable to have a layer that exhibits a structural color.
A second embodiment of the laminate according to the present disclosure includes a layer that exhibits structural color and has two or more reflective regions with different selective reflection wavelengths.
"Structural color" is the color that is produced when light interacts with the wavelength of visible light or fine structures at or below the wavelength of visible light through interference, diffraction, refraction, scattering, etc. It can also be found in many places in nature, such as insect shells, morpho butterflies, pearls, and the luster of opals.

It is preferable that the layer expressing a structural color has a center wavelength of selective reflection wavelength (hereinafter also referred to as "peak wavelength" or simply "selective reflection wavelength") defined below.
In the present disclosure, the "center wavelength of the selective reflection wavelength" refers to the maximum value of the reflectance in a target object (member), and the maximum value (hereinafter also simply referred to as "maximum reflectance") R _max (% ), it refers to the average value of two wavelengths showing a half-value reflectance R ^1/2 (%) expressed by the following formula. However, one of the two wavelengths is the maximum wavelength in the wavelength range that includes wavelengths shorter than the wavelength that indicates R _max , and the other wavelength is the wavelength that is shorter than the wavelength that indicates R _max . The minimum wavelength in the wavelength range that includes long wavelengths.
Formula for calculating half-value reflectance: R ^1/2 = R _max ÷ 2

The reflective region preferably selectively reflects at least a portion of light in the wavelength range of 380 nm to 820 nm from the viewpoint of visibility and reducing viewing angle dependence.
Furthermore, from the viewpoint of reducing viewing angle dependence, at least one of the reflective regions preferably selectively reflects at least part of the light in the wavelength range of 600 nm to 820 nm, and More preferably, at least part of the light is selectively reflected.
Further, from the viewpoint of reducing viewing angle dependence, at least two of the reflective regions preferably selectively reflect at least part of the light in the wavelength range of 600 nm to 820 nm, and More preferably, at least part of the light is selectively reflected.

Examples of layers that exhibit structural color include, but are not particularly limited to, organic multilayer layers, inorganic multilayer layers, cholesteric liquid crystal layers, and the like. Among these, the layer expressing structural color is preferably a layer made of a dielectric multilayer film or a cholesteric liquid crystal layer, and is preferably a layer made of an organic dielectric multilayer film, an inorganic dielectric multilayer film, or a cholesteric liquid crystal layer. A cholesteric liquid crystal layer is particularly preferred.
There are no particular limitations on the layer made of the dielectric multilayer film, but examples include a layer formed by alternately laminating two types of inorganic dielectrics, a layer formed by alternately laminating two types of organic dielectrics, etc. It will be done.

<<Organic multilayer film layer>>
As the organic multilayer film layer, a layer having a structure in which a resin layer with a high refractive index (layer A) and a resin layer with a low refractive index (layer B) are stacked is preferably mentioned.
From the viewpoint of visibility of pale colors and suppression of color change due to viewing angle, the layer B preferably has a refractive index lower than the layer A by 0.1 or more, and has a refractive index of 0.1 or more. It is more preferable that the layer has a low refractive index of 15 or more, it is even more preferable that the layer has a low refractive index of 0.2 or more, and it is particularly preferable that the layer has a low refractive index of 0.25 or more, and the refractive index is 0.25 or more. Most preferably, the layer is as low as 0.60 or less.
The refractive index of the layer A is preferably 1.5 or more, more preferably 1.6 or more, from the viewpoint of visibility of light color tone and suppression of color change due to viewing angle. It is more preferably 65 or more, and particularly preferably 1.70 or more. Further, the upper limit is preferably 2.3 or less, more preferably 1.9 or less.
The refractive index of the layer B is preferably 1.5 or less, more preferably less than 1.5, from the viewpoint of visibility of light color tone and suppression of color change due to viewing angle. It is more preferably 4 or less, particularly preferably 1.35 or less, and most preferably 1.32 or less. Further, the lower limit is preferably 1.1 or more, more preferably 1.2 or more, and particularly preferably 1.28 or more.
In the present disclosure, unless otherwise specified, the refractive index is a value measured using an ellipsometer at 25° C. and a wavelength of 550 nm.

The resin used for each layer such as layer A and layer B is not particularly limited, and examples thereof include acrylic resin, polycarbonate resin, polyester resin, polyolefin resin, epoxy resin, urethane resin, silicone resin, and the like.
The number of layers in the organic multilayer film layer is not particularly limited as long as it is two or more layers, but is preferably 100 to 2000 layers, more preferably 500 to 1500 layers, and even more preferably 800 to 1000 layers.
The thickness of the above-mentioned layer A and the above-mentioned layer B is preferably 50 nm to 1,000 nm, and 80 nm to 800 nm, independently from the viewpoint of visibility of pale color tone and suppression of color change depending on the viewing angle. It is more preferably 100 nm to 500 nm, and particularly preferably 100 nm to 300 nm.

<<Inorganic multilayer film layer>>
As the inorganic multilayer film layer, a layer having a structure in which two types of inorganic compounds are alternately laminated is preferably mentioned.
Further, from the viewpoint of visibility of light color tone and suppression of color change depending on the viewing angle, it is preferable that the two types of inorganic compounds are compounds having different refractive indexes.
Examples of inorganic compounds include silicon dioxide, aluminum oxide, gallium oxide, tungsten oxide, magnesium oxide, barium fluoride, calcium fluoride, cerium fluoride, lanthanum fluoride, lithium fluoride, sodium fluoride, magnesium fluoride, Neodymium fluoride, ytterbium fluoride, yttrium fluoride, gadolinium fluoride, calcium carbonate, potassium bromide, titanium monoxide, titanium dioxide, niobium pentoxide, chromium oxide, cerium oxide, silicon, zirconium oxide, gallium arsenide, etc. It will be done.
Among these, as the two types of inorganic compounds, a combination of inorganic oxides is preferable from the viewpoint of visibility of pale color tone and suppression of color change depending on the viewing angle, and niobium pentoxide (Nb ₂ O ₅ ) or titanium dioxide ( A combination of TiO ₂ ) and silicon dioxide (SiO ₂ ) or aluminum oxide (Al ₂ O ₃ ) is more preferred, and a combination of niobium pentoxide and silicon dioxide is particularly preferred.

The number of laminated layers in the inorganic multilayer film layer is not particularly limited as long as it is 2 or more layers, but is preferably 2 to 20 layers, more preferably 4 to 16 layers, and still more preferably 6 to 14 layers.
The thickness of each layer in the inorganic multilayer film layer is preferably 50 nm to 1,000 nm, and preferably 80 nm to 800 nm, from the viewpoint of visibility of pale color tone and suppression of color change due to viewing angle. is more preferable, further preferably from 100 nm to 500 nm, and particularly preferably from 100 nm to 300 nm.

<<Cholesteric liquid crystal layer>>
The layer expressing structural color is preferably a cholesteric liquid crystal layer. The cholesteric liquid crystal layer is a layer containing a cholesteric liquid crystal phase. The cholesteric liquid crystal phase is confirmed by known means (eg, polarized light microscopy and scanning electron microscopy).

It is known that a cholesteric liquid crystal phase is formed by a plurality of liquid crystal compounds arranged in a spiral shape. The alignment state of the liquid crystal compound in the cholesteric liquid crystal phase may be an alignment state that reflects right-handed circularly polarized light, left-handed circularly polarized light, or both right-handed circularly polarized light and left-handed circularly polarized light. The alignment state of the liquid crystal compound in the cholesteric liquid crystal phase may be fixed. The alignment state of the liquid crystal compound is fixed, for example, by polymerization or crosslinking of the liquid crystal compound. The liquid crystallinity of the liquid crystal compound may be lost in part or all of the liquid crystal compound whose alignment state has been fixed.

The cholesteric liquid crystal layer contributes to the design of the decorative material. For example, the color of the decorative material and the degree of change in the color of the decorative material depending on the viewing angle are adjusted by the helical pitch in the cholesteric liquid crystal phase, the refractive index of the cholesteric liquid crystal layer, and the thickness of the cholesteric liquid crystal layer. . The helical pitch may be adjusted by the amount of chiral agent added. The relationship between the helical structure and the chiral agent is described, for example, in "Fujifilm Research Report, No. 50 (2005), pp. 60-63." Moreover, the helical pitch may be adjusted by conditions such as temperature, illumination intensity, and irradiation time when fixing the cholesteric liquid crystal phase.

The laminate according to the present disclosure may include two or more cholesteric liquid crystal layers, and the compositions of the two or more cholesteric liquid crystal layers may be the same or different from each other.

From the viewpoint of reflectance, the thickness of the cholesteric liquid crystal layer is preferably 0.3 μm to 15 μm, more preferably 0.5 μm to 9 μm, and even more preferably 0.6 μm to 7 μm. When the laminate includes two or more cholesteric liquid crystal layers, it is preferable that the thicknesses of the two or more cholesteric liquid crystal layers are each independently within the range described above.

The components of the cholesteric liquid crystal layer are selected from known components of cholesteric liquid crystal layers, depending on the desired characteristics of the cholesteric liquid crystal layer, for example. Examples of the components of the cholesteric liquid crystal layer include components of the liquid crystal composition described below. However, when the cholesteric liquid crystal layer is formed through curing of the liquid crystal composition, some or all of the polymerizable compounds in the liquid crystal composition may form a polymer (including oligomers) in the cholesteric liquid crystal layer. . Examples of the polymerizable compound include compounds having a polymerizable group.

The cholesteric liquid crystal layer is preferably a layer formed by curing a composition containing a liquid crystal compound (hereinafter sometimes referred to as "liquid crystal composition"). Hereinafter, aspects of the liquid crystal composition will be specifically explained.

The liquid crystal composition includes a liquid crystal compound. The type of liquid crystal compound may be selected from known compounds having cholesteric liquid crystal properties (ie, cholesteric liquid crystal compounds), depending on the characteristics of the intended cholesteric liquid crystal layer, for example. Examples of the liquid crystal compound include liquid crystal compounds having at least one selected from the group consisting of ethylenically unsaturated groups and cyclic ether groups. From the viewpoint of improving moldability, the liquid crystal compound should include a cholesteric liquid crystal compound (hereinafter sometimes referred to as "specific liquid crystal compound") having one ethylenically unsaturated group or one cyclic ether group. is preferred.

Examples of the ethylenically unsaturated group in the specific liquid crystal compound include a (meth)acryloyloxy group, a (meth)acrylamide group, a vinyl group, a vinyl ester group, and a vinyl ether group. From the viewpoint of reactivity, the ethylenically unsaturated group is preferably a (meth)acryloyloxy group, a (meth)acrylamide group, or a vinyl group, and is preferably a (meth)acryloyloxy group or a (meth)acrylamide group. More preferred is a (meth)acryloyloxy group, even more preferred is an acryloyloxy group, and particularly preferred is an acryloyloxy group.

Examples of the cyclic ether group in the specific liquid crystal compound include an epoxy group and an oxetanyl group. From the viewpoint of reactivity, the cyclic ether group is preferably an epoxy group or an oxetanyl group, and more preferably an oxetanyl group.

From the viewpoint of improving reactivity and moldability, the liquid crystal compound preferably contains a liquid crystal compound having one ethylenically unsaturated group. Further, the ratio of the total amount of the liquid crystal compound having one ethylenically unsaturated group to the total amount of solid content of the liquid crystal composition is preferably 25% by mass or more.

When the number of ethylenically unsaturated groups contained in the molecule is one, the specific liquid crystal compound may have a functional group (for example, a polymerizable group) other than the ethylenically unsaturated group. For example, a liquid crystal compound having one ethylenically unsaturated group may have one or more cyclic ether groups.

When the number of cyclic ether groups contained in the molecule is one, the specific liquid crystal compound may have a functional group (for example, a polymerizable group) other than the cyclic ether group. For example, a liquid crystal compound having one cyclic ether group may have one or more ethylenically unsaturated groups.

From the viewpoint of improving moldability, the liquid crystal compound has one ethylenically unsaturated group and no cyclic ether group, and one cyclic ether group and no ethylenically unsaturated group. It is preferable to include a liquid crystal compound having no ethylenic unsaturated group or a liquid crystal compound having one ethylenically unsaturated group and one cyclic ether group. Furthermore, it is preferable that the liquid crystal compound contains one ethylenically unsaturated group and no cyclic ether group.

The specific liquid crystal compound may be a rod-like liquid crystal compound or a discotic liquid crystal compound. From the viewpoint of ease of adjustment of the helical pitch in the cholesteric liquid crystal phase and suppression of changes in reflectance and color after molding, rod-like liquid crystal compounds are preferred.

Preferred rod-like liquid crystal compounds include, for example, azomethine compounds, azoxy compounds, cyanobiphenyl compounds, cyanophenyl esters, benzoic acid esters, cyclohexanecarboxylic acid phenyl esters, cyanophenylcyclohexane compounds, cyano-substituted phenylpyrimidine compounds, alkoxy Examples include substituted phenylpyrimidine compounds, phenyldioxane compounds, tolan compounds, and alkenylcyclohexylbenzonitrile compounds. The rod-shaped liquid crystal compound is not limited to a low-molecular compound, and may be a high-molecular compound.

Rod-shaped liquid crystal compounds are described, for example, in "Makromol. Chem., Vol. 190, p. 2255 (1989)", "Advanced Materials, Vol. 5, p. 107 (1993)", US Pat. No. 4,683,327, US Pat. No. 5,622,648. specification, US Patent No. 5770107, WO 95/22586, WO 95/24455, WO 97/00600, WO 98/23580, WO 98/52905 One ethylenic compound described in JP-A-1-272551, JP-A-6-16616, JP-A-7-110469, JP-A-11-80081 and JP-A-2001-328973 It may be selected from compounds with unsaturated groups and compounds with one cyclic ether group. Preferred rod-like liquid crystal compounds are selected from, for example, compounds having one ethylenically unsaturated group and compounds having one cyclic ether group, which are described in Japanese Patent Publication No. 11-513019 and Japanese Patent Application Laid-Open No. 2007-279688. may be done.

Preferred discotic liquid crystal compounds are selected from, for example, compounds having one ethylenically unsaturated group and compounds having one cyclic ether group, which are described in JP-A-2007-108732 and JP-A-2010-244038. may be done.

Specific examples of specific liquid crystal compounds are shown below. However, the type of specific liquid crystal compound is not limited to the following specific examples.

The liquid crystal composition may contain one or more cholesteric liquid crystal compounds.

From the viewpoint of improving stretchability and heat durability, the ratio of the total amount of the specific liquid crystal compound to the total amount of solid content of the liquid crystal composition is preferably 25% by mass or more, and more preferably 30% by mass or more. , more preferably 40% by mass or more. Furthermore, the ratio of the total amount of the specific liquid crystal compound to the total amount of solid content of the liquid crystal composition is preferably 60% by mass to 99% by mass, more preferably 80% by mass to 98% by mass.

The liquid crystal composition may also contain other liquid crystal compounds. Other liquid crystal compounds mean liquid crystal compounds other than the specific liquid crystal compound. Other liquid crystal compounds include, for example, a liquid crystal compound that does not have an ethylenically unsaturated group and a cyclic ether group, a liquid crystal compound that has two or more ethylenically unsaturated groups and no cyclic ether group, and a liquid crystal compound that has two or more ethylenically unsaturated groups and no cyclic ether group. Examples include liquid crystal compounds having the above cyclic ether groups and no ethylenically unsaturated groups, and liquid crystal compounds having two or more ethylenically unsaturated groups and two or more cyclic ether groups.

From the viewpoint of suppressing reflectance changes and color changes after molding, other liquid crystal compounds include liquid crystal compounds having no ethylenically unsaturated group and cyclic ether group, having two or more ethylenically unsaturated groups, In addition, it is preferably at least one selected from the group consisting of a liquid crystal compound having no cyclic ether group and a liquid crystal compound having two or more cyclic ether groups and no ethylenically unsaturated group. Other liquid crystal compounds include liquid crystal compounds that do not have an ethylenically unsaturated group and a cyclic ether group, liquid crystal compounds that have two ethylenically unsaturated groups and no cyclic ether group, and liquid crystal compounds that have two ethylenically unsaturated groups and no cyclic ether group. It is more preferable that the liquid crystal compound is at least one selected from the group consisting of liquid crystal compounds having the following formula and having no ethylenically unsaturated group. The other liquid crystal compound is at least selected from the group consisting of a liquid crystal compound having no ethylenically unsaturated group and no cyclic ether group, and a liquid crystal compound having two ethylenically unsaturated groups and no cyclic ether group. More preferably, it is one type.

Rod-shaped liquid crystal compounds among other liquid crystal compounds are described, for example, in "Makromol. Chem., Vol. 190, p. 2255 (1989)", "Advanced Materials, Vol. 5, p. 107 (1993)", and US Pat. No. 4,683,327. , US Pat. No. 5,622,648, US Pat. No. 5,770,107, WO 95/22586, WO 95/24455, WO 97/00600, WO 98/23580, International Described in Publication No. 98/52905, JP 1-272551, JP 6-16616, JP 7-110469, JP 11-80081, and JP 2001-328973 may be selected from compounds. Preferred rod-like liquid crystal compounds among other liquid crystal compounds may be selected from, for example, compounds described in Japanese Patent Publication No. 11-513019 and Japanese Patent Application Laid-open No. 2007-279688.

Preferred discotic liquid crystal compounds among other liquid crystal compounds may be selected from, for example, the compounds described in JP-A No. 2007-108732 or JP-A No. 2010-244038.

Specific examples of other liquid crystal compounds are shown below. However, the types of other liquid crystal compounds are not limited to the following specific examples.

The liquid crystal composition may contain one or more other liquid crystal compounds.

The ratio of the total amount of other liquid crystal compounds to the total solid content of the liquid crystal composition is preferably 70% by mass or less, more preferably 50% by mass or less, and even more preferably 30% by mass or less. , 20% by mass or less is particularly preferred. Note that the lower limit of the above ratio is 0% by mass.

The liquid crystal composition may contain one or more liquid crystal compounds. The liquid crystal composition may include a specific liquid compound and another liquid crystal compound.

The ratio of the total amount of liquid crystal compounds to the total solid content of the liquid crystal composition is preferably 25% by mass or more, more preferably 30% by mass or more, and even more preferably 40% by mass or more. Further, the ratio of the total amount of liquid crystal compounds to the total amount of solid content of the liquid crystal composition is preferably 60% by mass to 99% by mass, more preferably 80% by mass to 98% by mass.

-Chiral agent-
From the viewpoint of ease of forming a cholesteric liquid crystal layer and ease of adjusting the helical pitch, the liquid crystal composition preferably contains a chiral agent (that is, an optically active compound).

The type of chiral agent may be determined depending on, for example, the type of liquid crystal compound and the desired helical structure (for example, the twisting method of the helix and the helical pitch). Examples of chiral agents include known compounds (for example, Liquid Crystal Device Handbook, Chapter 3, Section 4-3, Chiral Agents for TN (twisted nematic) and STN (Super-twisted nematic), p. 199, Japan Society for the Promotion of Science, Vol. 142 Committee, 1989), isosorbide derivatives and isomannide derivatives.

Chiral agents generally contain asymmetric carbon atoms. However, axially asymmetric compounds and planar asymmetric compounds that do not contain asymmetric carbon atoms can be used as chiral agents. Preferred examples of the axially asymmetric compound or planar asymmetric compound include binaphthyl compounds, helicene compounds, and paracyclophane compounds.

From the viewpoint of improving thermal durability, the liquid crystal composition may contain a chiral agent having a polymerizable group. From the viewpoint of improving reactivity and heat durability, the polymerizable group is preferably an ethylenically unsaturated group or a cyclic ether group, and more preferably an ethylenically unsaturated group. The preferred embodiment of the ethylenically unsaturated group in the chiral agent is the same as the preferred embodiment of the ethylenically unsaturated group in the specific liquid crystal compound described above. The preferred embodiment of the cyclic ether group in the chiral agent is the same as the preferred embodiment of the cyclic ether group in the specific liquid crystal compound described above.

When the chiral agent has a polymerizable group, from the viewpoint of improving reactivity and thermal durability, the type of polymerizable group in the chiral agent is preferably the same as the type of polymerizable group in the specific liquid crystal compound. Furthermore, the polymerizable group in the chiral agent is preferably the same as the polymerizable group in the specific liquid crystal compound.

From the viewpoint of improving moldability, a chiral agent having a polymerizable group is a chiral agent having one ethylenically unsaturated group and no cyclic ether group, and a chiral agent having one cyclic ether group, and It is preferable to include a chiral agent having no ethylenically unsaturated group or a chiral agent having one ethylenically unsaturated group and one cyclic ether group. Further, the chiral agent having a polymerizable group preferably includes a chiral agent having one ethylenically unsaturated group and no cyclic ether group.

The chiral agent may be a liquid crystal compound.

--Photosensitive chiral agent--
The cholesteric liquid crystal layer preferably contains a chiral agent (photosensitive chiral agent) having a site that isomerizes upon irradiation with light.
A photosensitive chiral agent whose helical inducing force changes upon irradiation with light will be described in detail.
Note that the helical inducing force (HTP) of the chiral agent is a factor indicating the helical orientation ability expressed by the following formula (A).
Formula (A) HTP=1/(Length of helical pitch (unit: μm) x Concentration of chiral agent in liquid crystal compound (mass%)) [μm ⁻¹ ]
The length of the helical pitch refers to the length of the pitch P (=period of the helix) of the helical structure of the cholesteric liquid crystal phase, and can be measured by the method described on page 196 of Liquid Crystal Handbook (published by Maruzen Co., Ltd.).

The photosensitive chiral agent whose helical inducing force changes upon light irradiation may be liquid crystalline or non-liquid crystalline. Photosensitive chiral agents generally often contain asymmetric carbon atoms. Note that the photosensitive chiral agent may be an axially asymmetric compound or a planar asymmetric compound that does not contain an asymmetric carbon atom.

The photosensitive chiral agent may be a chiral agent whose helical inducing force increases or decreases when irradiated with light. Among these, chiral agents whose helical inducing force decreases upon irradiation with light are preferred.
In this specification, "increase and decrease in helical inducing force" refers to an increase and decrease when the initial (before light irradiation) helical direction of the photosensitive chiral agent is defined as "positive". Therefore, if the helical inducing force continues to decrease due to light irradiation and exceeds 0 and the helical direction becomes "negative" (in other words, a spiral in the opposite helical direction to the initial (before light irradiation) helical direction is induced) case) also falls under the category of "chiral agents whose helical inducing force decreases."

Examples of the photosensitive chiral agent include so-called photoreactive chiral agents. A photoreactive chiral agent is a compound that has a chiral moiety and a photoreactive moiety whose structure changes upon irradiation with light, and for example, causes a large change in the twisting force of a liquid crystal compound depending on the amount of irradiation.
Examples of photoreactive sites whose structure changes upon light irradiation include photochromic compounds (Kingo Uchida, Masahiro Irie, Kagaku Kogyo, vol. 64, 640p, 1999, Kingo Uchida, Masahiro Irie, Fine Chemical, vol. 28 (9), 15 p. , 1999). In addition, the above-mentioned structural change means decomposition, addition reaction, isomerization, racemization, [2+2] photocyclization, dimerization reaction, etc. caused by light irradiation to the photoreaction site, and the above-mentioned structural change is irreversible. There may be. Further, as a chiral moiety, for example, Hiroyuki Nohira, Chemistry Review, No. This corresponds to the asymmetric carbon described in 22 Chemistry of Liquid Crystals, 73p: 1994.

Examples of photosensitive chiral agents include photoreactive chiral agents described in paragraphs 0044 to 0047 of JP-A No. 2001-159709, optically active compounds described in paragraphs 0019 to 0043 of JP-A No. 2002-179669, and Optically active compounds described in paragraphs 0020 to 0044 of JP 2002-179633, optically active compounds described in paragraphs 0016 to 0040 of JP 2002-179670, and paragraphs 0017 to 0050 of JP 2002-179668. optically active compounds described in paragraphs 0018 to 0044 of JP 2002-180051, optically active isosorbide derivatives described in paragraphs 0016 to 0055 of JP 2002-338575, JP 2002-080478; Photoreactive optically active compounds described in paragraphs 0023 to 0032 of JP-A No. 2002-080851, photoreactive chiral agents described in paragraphs 0019 to 0029 of JP-A No. 2002-179681, and paragraphs 0022 to 0049 of JP-A No. 2002-179681. optically active compounds described in paragraphs 0015 to 0044 of JP 2002-302487, optically active polyesters described in paragraphs 0015 to 0050 of JP 2002-338668, JP 2003-055315 Binaphthol derivatives described in paragraphs 0019 to 0041 of JP-A No. 2003-073381, optically active fulgide compounds described in paragraphs 0008 to 0043 of JP-A No. 2003-306490, and optically active compounds described in paragraphs 0015 to 0057 of JP-A No. 2003-306490. Isosorbide derivatives, optically active isosorbide derivatives described in paragraphs 0015 to 0041 of JP 2003-306491, optically active isosorbide derivatives described in paragraphs 0015 to 0049 of JP 2003-313187, JP 2003-313188 optically active isomannide derivatives described in paragraphs 0015 to 0057 of JP 2003-313189, optically active isosorbide derivatives described in paragraphs 0015 to 0052 of JP 2003-313292, Examples include polyester/amide, optically active compounds described in paragraphs 0012 to 0053 of International Publication No. 2018/194157, and optically active compounds described in paragraphs 0020 to 0049 of JP 2002-179682.

Among the photosensitive chiral agents, compounds having at least a photoisomerization site are preferable, and it is more preferable that the photoisomerization site has a photoisomerizable double bond. The photoisomerization site having the photoisomerizable double bond is a cinnamoyl site, a chalcone site, an azobenzene site, or A stilbene moiety is preferred, and a cinnamoyl moiety, a chalcone moiety, or a stilbene moiety is more preferred in terms of low absorption of visible light. Note that the photoisomerization site corresponds to the above-mentioned photoreaction site whose structure changes upon irradiation with light.

In addition, photosensitive chiral agents have a high initial helical inducing force (before light irradiation) and a superior change in the helical inducing force upon light irradiation, and have a trans-type photoisomerizable double bond. It is preferable to have.
In addition, photosensitive chiral agents have a cis-type photoisomerizable double bond, which has a low initial helical inducing force (before light irradiation) and a better change in helical inducing force upon light irradiation. It is preferable to have.

The photosensitive chiral agent has any partial structure selected from the group consisting of a binaphthyl partial structure, an isosorbide partial structure (a partial structure derived from isosorbide), and an isomannide partial structure (a partial structure derived from isomannide). Preferably. Note that the binaphthyl partial structure, isosorbide partial structure, and isomannide partial structure are each intended to have the following structures.
A portion in the binaphthyl partial structure where the solid line and the broken line are parallel represents a single bond or a double bond. In addition, in the structure shown below, * represents a bonding position.

The photosensitive chiral agent may have a polymerizable group. The type of polymerizable group is not particularly limited, and a functional group capable of an addition polymerization reaction is preferable, a polymerizable ethylenically unsaturated group or a ring polymerizable group is more preferable, and a (meth)acryloyl group, a vinyl group, a styryl group, Alternatively, an allyl group is more preferred.

As the photosensitive chiral agent, a compound represented by formula (C) is preferred.
Formula (C) R-LR
R each independently represents a group having at least one moiety selected from the group consisting of a cinnamoyl moiety, a chalcone moiety, an azobenzene moiety, and a stilbene moiety.
L is a divalent linking group formed by removing two hydrogen atoms from the structure represented by formula (D) (a divalent linking group formed by removing two hydrogen atoms from the above binaphthyl partial structure) group), a divalent linking group represented by formula (E) (a divalent linking group consisting of the above isosorbide partial structure), or a divalent linking group represented by formula (F) (a divalent linking group consisting of the above isomannide partial structure) represents a divalent linking group consisting of
In formula (E) and formula (F), * represents a bonding position.

Specific examples of photosensitive chiral agents are shown below. However, the type of photosensitive chiral agent is not limited to the following specific examples.

To form a layer that exhibits structural color, one kind of photosensitive chiral agent may be used alone, or two or more kinds of photosensitive chiral agents may be used.

The molar extinction coefficient of the photosensitive chiral agent is not particularly limited, but the molar extinction coefficient at the wavelength (for example, 365 nm) of the light irradiated in the torsional change step described below is 100 L/(mol cm) to 100,000 L/( mol·cm) is preferable, and 500 L/(mol·cm) to 50,000 L/(mol·cm) is more preferable.

--Polymerizable chiral agent--
The cholesteric liquid crystal layer may contain a polymerizable chiral agent as a chiral agent from the viewpoint of more easily fixing the helical structure of the cholesteric liquid crystal compound. A polymerizable chiral agent means a chiral agent having a polymerizable group. The polymerizable chiral agent referred to herein is one whose helical inducing force does not change due to light irradiation, and is distinguished from the photosensitive chiral agent.

Examples of the polymerizable group that the polymerizable chiral agent has include a radically polymerizable group and a cationic polymerizable group. The polymerizable group is preferably an ethylenically unsaturated group, an epoxy group or an aziridinyl group, and more preferably an ethylenically unsaturated group.

The polymerizable chiral agent is preferably a compound containing an asymmetric carbon atom, but may be an axially asymmetric compound or a planar asymmetric compound that does not contain an asymmetric carbon atom. Examples of axially asymmetric compounds or planar asymmetric compounds include binaphthyl, helicene, paracyclophane, and derivatives thereof.

When the cholesteric liquid crystal layer contains a cholesteric liquid crystal compound having a polymerizable group, the polymerizable chiral agent preferably contains the same type of polymerizable group as the polymerizable group that the cholesteric liquid crystal compound has. For example, when the cholesteric liquid crystal compound has a radically polymerizable group, it is preferable that the polymerizable chiral agent also contains a radically polymerizable group. As a result, a polymer in which the cholesteric liquid crystal compound having a polymerizable group and the polymerizable chiral agent are polymerized is formed, and the helical structure of the cholesteric liquid crystal compound can be more easily fixed.

The polymerizable chiral agent is preferably an isosorbide derivative, an isomannide derivative, or a binaphthyl derivative. Examples of commercially available isosorbide derivatives include "Paliocolor LC756" manufactured by BASF.

One type of polymerizable chiral agent may be used alone, or two or more types may be used in combination.

The liquid crystal composition may contain one or more chiral agents.

The content of the chiral agent may be determined, for example, depending on the structure of the liquid crystal compound and the desired helical pitch. From the viewpoint of ease of forming a cholesteric liquid crystal layer and ease of adjusting the helical pitch, the ratio of the total amount of chiral agent to the total amount of solid content of the liquid crystal composition is preferably 1% by mass to 20% by mass, and 2% by mass. % to 15% by weight, and even more preferably 3% to 10% by weight.

The helical pitch in the cholesteric liquid crystal phase and the selective reflection wavelength of the layer expressing structural color are easily adjusted not only by the type of liquid crystal compound but also by the content of the chiral agent. For example, when the content of the chiral agent in the liquid crystal composition is doubled, the helical pitch becomes 1/2, and the central value of the selective reflection wavelength may also become 1/2.

It is preferable that the liquid crystal composition contains a polymerization initiator. The polymerization initiator accelerates the curing reaction of the liquid crystal composition.

When the liquid crystal composition is cured by exposure, it is preferable that the liquid crystal composition contains a photopolymerization initiator. Examples of the photopolymerization initiator include radical photopolymerization initiators and cationic photopolymerization initiators.

Examples of photopolymerization initiators include α-carbonyl compounds (e.g., US Pat. No. 2,367,661 and US Pat. No. 2,367,670), acyloin ether compounds (e.g., US Pat. No. 2,448,828), α - Hydrocarbon-substituted aromatic acyloin compounds (e.g., U.S. Pat. No. 2,722,512), polynuclear quinone compounds (e.g., U.S. Pat. No. 3,046,127 and U.S. Pat. No. 2,951,758), triarylimidazole dimers and p- Combinations with aminophenyl ketones (e.g., US Pat. No. 3,549,367), oxadiazole compounds (e.g., US Pat. No. 4,212,970), acridine compounds and phenazine compounds (e.g., JP-A-60-105667) and US Pat. No. 4,239,850).

Preferred radical photopolymerization initiators include, for example, α-hydroxyalkylphenone compounds, α-aminoalkylphenone compounds, and acylphosphine oxide compounds.

Preferred photocationic polymerization initiators include, for example, iodonium salt compounds and sulfonium salt compounds.

The liquid crystal composition preferably contains a radical polymerization initiator or a cationic polymerization initiator, and more preferably contains a radical photopolymerization initiator or a cationic photopolymerization initiator.

From the viewpoint of improving thermal durability, the liquid crystal composition containing a liquid crystal compound having one ethylenically unsaturated group preferably contains a radical polymerization initiator, and more preferably contains a photoradical polymerization initiator.

From the viewpoint of improving thermal durability, a liquid crystal composition containing a liquid crystal compound having one cyclic ether group preferably contains a cationic polymerization initiator, and more preferably contains a photocationic polymerization initiator.

The liquid crystal composition may contain one or more types of polymerization initiators.

The content of the polymerization initiator may be determined, for example, depending on the structure of the specific liquid crystal compound and the desired helical pitch. From the viewpoint of ease of forming the cholesteric liquid crystal layer, ease of adjusting the helical pitch, polymerization rate, and strength of the cholesteric liquid crystal layer, the ratio of the total amount of polymerization initiator to the total amount of solid content of the liquid crystal composition is 0.05% by mass. It is preferably 10% by mass, more preferably 0.05% by mass to 5% by mass or less, even more preferably 0.1% to 2% by mass, and even more preferably 0.2% to 1% by mass. Particularly preferred is mass %.

From the viewpoint of improving the strength and durability of the cholesteric liquid crystal layer after curing, the liquid crystal composition may contain a crosslinking agent. Preferred crosslinking agents include, for example, compounds that are cured by external factors such as ultraviolet light, heat, and moisture.

Examples of the crosslinking agent include the compounds shown below.
(1) Polyfunctional acrylate compounds (e.g., trimethylolpropane tri(meth)acrylate and pentaerythritol tri(meth)acrylate)
(2) Epoxy compounds (e.g. glycidyl (meth)acrylate and ethylene glycol diglycidyl ether)
(3) Aziridine compounds (e.g., 2,2-bishydroxymethylbutanol-tris[3-(1-aziridinyl)propionate] and 4,4-bis(ethyleneiminocarbonylamino)diphenylmethane)
(4) Isocyanate compounds (e.g. hexamethylene diisocyanate and biuret-type isocyanate)
(5) Polyoxazoline compounds having oxazoline groups in their side chains (6) Alkoxysilane compounds (e.g. vinyltrimethoxysilane and N-(2-aminoethyl)3-aminopropyltrimethoxysilane)

The liquid crystal composition may contain one or more crosslinking agents.

From the viewpoint of strength and durability of the cholesteric liquid crystal layer, the ratio of the total amount of crosslinking agent to the total amount of solid content of the liquid crystal composition is preferably 1% by mass to 20% by mass, and 3% by mass to 15% by mass. It is more preferable that there be.

The liquid crystal composition may contain a known catalyst depending on the reactivity of the crosslinking agent. The combined use of a crosslinking agent and a catalyst can not only improve the strength and durability of the cholesteric liquid crystal layer, but also improve productivity.

The liquid crystal composition may contain a polyfunctional polymerizable compound. A polyfunctional polymerizable compound means a compound having two or more polymerizable groups. It is preferable that the types of two or more polymerizable groups contained in the polyfunctional polymerizable compound are the same.

Examples of the polyfunctional polymerizable compound include a liquid crystal compound having two or more ethylenically unsaturated groups and no cyclic ether group, and a liquid crystal compound having two or more cyclic ether groups and no ethylenically unsaturated group. Liquid crystal compounds having no saturated groups, liquid crystal compounds having two or more ethylenically unsaturated groups and two or more cyclic ether groups, chiral agents having two or more polymerizable groups, and two or more polymerizable groups Examples include crosslinking agents having the following. Polyfunctional polymerizable compounds include liquid crystal compounds that have two or more ethylenically unsaturated groups and no cyclic ether groups, and liquid crystal compounds that have two or more cyclic ether groups and no ethylenically unsaturated groups. It is preferable to include at least one kind selected from the group consisting of a liquid crystal compound that does not have a chiral agent and a chiral agent that has two or more polymerizable groups, and more preferably a chiral agent that has two or more polymerizable groups.

The liquid crystal composition may contain one or more polyfunctional polymerizable compounds.

From the viewpoint of improving moldability and suppressing changes in orientation structure after polymerization, the ratio of the total amount of the polyfunctional polymerizable compound to the total amount of solid content of the liquid crystal composition is preferably 0.5% by mass to 50% by mass. It is preferably 1% by mass to 40% by mass, even more preferably 1.5% by mass to 30% by mass, and particularly preferably 2% by mass to 20% by mass. As the ratio of the total amount of polyfunctional polymerizable compounds to the total amount of solid content of the liquid crystal composition decreases, the crosslinking density of the cholesteric liquid crystal layer decreases. As a result, the stretchability of the cholesteric liquid crystal layer is improved, and the moldability is improved. When the ratio of the total amount of the polyfunctional polymerizable compound to the total amount of solid content of the liquid crystal composition increases, the alignment structure of the cholesteric liquid crystal layer is easily maintained after polymerization. From the viewpoint of improving moldability, among polyfunctional polymerizable compounds, compounds having two or more ethylenically unsaturated groups, compounds having two or more cyclic ether groups, and compounds having one or more ethylenically unsaturated groups are used. It is preferable that the content of the compound having one or more cyclic ether groups is regulated. In other words, "compounds having two or more ethylenically unsaturated groups, compounds having two or more cyclic ether groups, and compounds having one or more ethylenically unsaturated groups and one or more The ratio of "total amount of compounds having a cyclic ether group" is preferably 0.5% to 50% by mass, more preferably 1% to 40% by mass, and 1.5% to 30% by mass. It is more preferably % by mass, and particularly preferably 2% by mass to 20% by mass.

The liquid crystal composition may contain other additives as necessary. Other additives include, for example, surfactants, polymerization inhibitors, antioxidants, horizontal alignment agents, ultraviolet absorbers, light stabilizers, colorants, and metal oxide particles. The liquid crystal composition may also contain one or more other additives.

The liquid crystal composition may contain a solvent. Preferably, the solvent is an organic solvent. Examples of organic solvents include ketones (eg, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone), alkyl halides, amides, sulfoxides, heterocyclic compounds, hydrocarbons, esters, and ethers. Ketones are preferable in consideration of the burden on the environment.

The liquid crystal composition may contain one or more solvents.

The content of the solvent may be determined, for example, depending on the coatability of the liquid crystal composition.

The ratio of the total solid content of the liquid crystal composition to the total amount of the liquid crystal composition is preferably 1% by mass to 90% by mass, more preferably 5% to 80% by mass, and 10% to 80% by mass. It is more preferable that it is mass %.

When the liquid crystal composition is cured in the process of forming a cholesteric liquid crystal layer, the ratio of the total amount of solvent to the total amount of solid content of the liquid crystal composition at the time of curing the liquid crystal composition is preferably 5% by mass or less, and 3% by mass or less. It is more preferably at most 2% by mass, even more preferably at most 2% by mass, and particularly preferably at most 1% by mass.

The ratio of the total amount of solvent in the cholesteric liquid crystal layer to the total amount of the cholesteric liquid crystal layer is preferably 5% by mass or less, more preferably 3% by mass or less, even more preferably 2% by mass or less, and 1 It is particularly preferable that it is less than % by mass.

The method for producing the liquid crystal composition is not limited. A liquid crystal composition is manufactured, for example, by mixing a liquid crystal compound and a component other than the liquid crystal compound. The mixing method may be selected from known mixing methods.

Curing of the liquid crystal composition is performed, for example, by exposure. Exposure is performed, for example, by irradiating the liquid crystal composition with light. A preferable light source includes, for example, a light source that can irradiate light containing at least one type selected from the group consisting of 365 nm and 405 nm. Specific light sources include, for example, ultra-high-pressure mercury lamps, high-pressure mercury lamps, and metal halide lamps. The exposure amount is preferably 5 mJ/cm ² to 2,000 mJ/cm ² , more preferably 10 mJ/cm ² to 1,000 mJ/cm ² . As the exposure method, for example, the method described in paragraphs 0035 to 0051 of JP-A No. 2006-23696 may be applied.

In order to facilitate alignment of the liquid crystal compound, it is preferable to expose the liquid crystal composition while heating it. The heating temperature is determined, for example, depending on the composition of the liquid crystal composition. The heating temperature is, for example, 60°C to 120°C. Examples of heating means include heaters, ovens, hot plates, infrared lamps, and infrared lasers.

Curing of the liquid crystal composition may be performed, for example, by heating. The heating temperature is preferably 60°C to 200°C. The heating time is preferably 5 minutes to 2 hours. Examples of the heating means include the heating means described above.

The liquid crystal composition may be dried by a known method before curing. The liquid crystal composition may be left to dry or air-dried. The liquid crystal composition may be dried by heating.

Further, the thickness of the layer expressing structural color is not particularly limited, but from the viewpoint of obtaining a more appropriate reflectance, it is preferably 0.1 μm to 10 μm, more preferably 0.3 μm to 8 μm. , more preferably 0.5 μm to 6 μm.

〔Base material〕
The laminate may include a base material. This increases the strength of the laminate, making it easier to handle. Further, when the laminate includes a base material, the base material can be used as a member constituting a molded product formed by molding the laminate.

In an embodiment in which the laminate includes a base material, the layer expressing structural color may be provided directly on the base material, or may be provided via another layer.

The shape and material of the base material are not particularly limited, and may be appropriately selected as desired. When molding a laminate, the base material is preferably a resin base material from the viewpoint of ease of molding.

Examples of the material of the resin base material include polyethylene (PE), polyethylene naphthalate (PEN), polyamide (PA), polyethylene terephthalate (PET), polyvinyl chloride (PVC), polyvinyl alcohol (PVA), and polyacrylonitrile (PAN). ), polyimide (PI), polymethyl methacrylate (PMMA), polycarbonate (PC), acrylic-polycarbonate resin, polyacrylate, polymethacrylate, polypropylene (PP), polystyrene (PS), polyacrylonitrile-butadiene-styrene copolymer (ABS), cyclic olefin-copolymers (COC), cycloolefin polymers (COP), triacetyl cellulose (TAC), urethane resins, and urethane-acrylic resins. From the viewpoint of the strength of the laminate and the moldability when molding the laminate, the material of the base material is polyethylene terephthalate, acrylic resin, urethane resin, urethane-acrylic resin, polycarbonate, acrylic-polycarbonate resin, and Preferably, it is at least one resin selected from the group consisting of polypropylene. The base material may be a laminate of a plurality of resin layers made of different materials.

The resin base material may contain additives as necessary. Examples of additives include lubricants such as mineral oil, hydrocarbons, fatty acids, alcohols, fatty acid esters, fatty acid amides, metal soaps, natural waxes, and silicones; inorganic flame retardants such as magnesium hydroxide and aluminum hydroxide; and halogen-based retardants. Organic flame retardants such as flame retardants and phosphorus flame retardants; organic or inorganic fillers such as metal powder, talc, calcium carbonate, potassium titanate, glass fiber, carbon fiber, and wood flour; antioxidants, ultraviolet inhibitors, and lubricants. , a dispersant, a coupling agent, a foaming agent, a coloring agent, and a resin other than the main component resin.

The resin base material may be a commercially available product. Commercially available products include, for example, the Technoloy (registered trademark) series (acrylic resin film, polycarbonate resin film, or acrylic resin/polycarbonate resin laminated film, manufactured by Sumitomo Chemical Co., Ltd.), ABS film (manufactured by Okamoto Co., Ltd.), and ABS sheet (Sekisui Molding Co., Ltd.). (manufactured by Kogyo Co., Ltd.), Teflex (registered trademark) series (PET film, manufactured by Teijin Film Solutions Co., Ltd.), Lumirror (registered trademark) easy molding type (PET film, manufactured by Toray Industries, Ltd.), and Pure Thermo (polypropylene film, manufactured by Idemitsu Unitech Co., Ltd.) (manufactured by).

The thickness of the base material is not particularly limited, but from the viewpoint of the strength of the laminate and the moldability when molding the laminate, it is preferably 1 μm or more, more preferably 10 μm or more, and still more preferably 20 μm or more. preferable. Moreover, from the same viewpoint, the thickness of the base material is preferably 300 μm or less, more preferably 200 μm or less, and even more preferably 150 μm or less.

For example, when the laminate includes a base material, the laminate may be obtained by peeling the base material from the laminate containing the base material.

[Colored layer]
The laminate may include a colored layer. This makes it easier to obtain a desired design. The colored layer is a layer containing a coloring agent. The number of colored layers may be one layer, or two or more layers.

In the laminate, the position of the colored layer is not particularly limited, and may be provided at any desired position. For example, a colored layer may be provided on a layer that exhibits structural color. In addition, when the laminate includes a base material, it may be provided on the side opposite to the side on which the layer expressing the structural color of the base material is formed, and the base material may be peeled off from the laminate containing the base material. It may be formed into a laminate and provided on the laminate after peeling off the base material.

The color of the colored layer is not particularly limited, and can be appropriately selected depending on the use of the laminate. Examples of the color of the colored layer include black, gray, white, red, orange, yellow, green, blue, purple, and brown. Moreover, the color of the colored layer may be a metallic color.

-Coloring agent-
The colorant may be a pigment or a dye. From the viewpoint of durability, the colorant is preferably a pigment. In order to give the colored layer a metallic tone, metal particles, pearl pigments, etc. may be used as the coloring agent.

The pigment may be an inorganic pigment or an organic pigment.

Examples of inorganic pigments include white pigments such as titanium dioxide, zinc oxide, lithopone, light calcium carbonate, white carbon, aluminum oxide, aluminum hydroxide, and barium sulfate; carbon black, titanium black, titanium carbon, iron oxide, graphite, etc. black pigments; iron oxide, barium yellow, cadmium red, and chrome yellow.

Examples of inorganic pigments include the inorganic pigments described in paragraphs 0015 and 0114 of JP-A No. 2005-7765.

Examples of organic pigments include phthalocyanine pigments such as phthalocyanine blue and phthalocyanine green; azo pigments such as azo red, azo yellow, and azo orange; quinacridone pigments such as quinacridone red, shinkasha red, and shinkasha magenta; perylene red, Perylene pigments such as perylene maroon; carbazole violet, anthrapyridine, flavanthrone yellow, isoindoline yellow, induthrone blue, dibrom anthathurone red, anthraquinone red, and diketopyrrolopyrrole.

Specific examples of organic pigments include C.I. I. Pigment Red 177, 179, 224, 242, 254, 255, 264 and other red pigments, C.I. I. Pigment Yellow 138, 139, 150, 180, 185 and other yellow pigments; C.I. I. Pigment Orange 36, 38, 71, and other orange pigments; C.I. I. Pigment Green 7, 36, 58 and other green pigments; C.I. I. Pigment Blue 15:6 and other blue pigments; and C.I. I. Examples include purple pigments such as Pigment Violet 23.

Examples of organic pigments include organic pigments described in paragraph 0093 of JP-A No. 2009-256572.

The pigment may be a pigment that has light transmittance and light reflectivity (so-called glitter pigment). Examples of bright pigments include metal bright pigments of aluminum, copper, zinc, iron, nickel, tin, aluminum oxide, and alloys thereof, interference mica pigments, white mica pigments, graphite pigments, and glass flake pigments. can be mentioned. The glitter pigment may be uncolored or colored.

One type of colorant may be used alone, or two or more types may be used in combination. When using two or more types of colorants, an inorganic pigment and an organic pigment may be combined.

From the viewpoint of desired color expression, the content of the colorant is preferably 1% by mass to 50% by mass, more preferably 5% by mass to 50% by mass, based on the total amount of the colored layer. , 10% by mass to 40% by mass is particularly preferred.

-Binder resin-
The colored layer preferably contains a binder resin from the viewpoints of strength, scratch resistance, and suitability for molding. The type of binder resin is not particularly limited. From the viewpoint of obtaining a desired color, the binder resin is preferably a transparent resin, and specifically, a resin having a total light transmittance of 80% or more is preferable. The total light transmittance can be measured with a spectrophotometer (eg, spectrophotometer "UV-2100" manufactured by Shimadzu Corporation).

Examples of the binder resin include acrylic resin, silicone resin, polyester, polyurethane, and polyolefin. The binder resin may be a homopolymer or a copolymer.

One type of binder resin may be used alone, or two or more types may be used in combination.

From the viewpoint of moldability, the content of the binder resin is preferably 5% by mass to 70% by mass, more preferably 10% by mass to 60% by mass, and 20% by mass, based on the total amount of the colored layer. Particularly preferred is % by weight to 60% by weight.

-Dispersant-
From the viewpoint of improving the dispersibility of the colorant contained in the colored layer, especially the pigment, the colored layer may contain a dispersant. When a dispersant is included, the dispersibility of the colorant in the colored layer is improved. Therefore, the color of the resulting laminate can be more easily made uniform.

The dispersant can be appropriately selected depending on the type, shape, etc. of the colorant, and is preferably a polymer dispersant.

Examples of polymeric dispersants include silicone polymers, acrylic polymers, and polyester polymers. For example, when it is desired to impart heat resistance to the laminate, the dispersant is preferably a silicone polymer such as a grafted silicone polymer.

The weight average molecular weight of the dispersant is preferably 1,000 to 5,000,000, more preferably 2,000 to 3,000,000, and more preferably 2,500 to 3,000,000. It is particularly preferable. When the weight average molecular weight is 1,000 or more, the dispersibility of the colorant is further improved.

The dispersant may be a commercially available product. Commercially available dispersants include EFKA 4300 (acrylic polymer dispersant) manufactured by BASF Japan; homogenol L-18, homogenol L-95, and homogenol L-100 manufactured by Kao; and homogenol L-100 manufactured by Japan Lubrizol. , Solsperse 20000, and Solsperses 24000; and DISPERBYK-110, DISPERBYK-164, DISPERBYK-180, and DISPERBYK-182 manufactured by BYK Chemie Japan. Note that "Homogenol," "Solsperse," and "DISPERBYK" are all registered trademarks.

One type of dispersant may be used alone, or two or more types may be used in combination.

The content of the dispersant is preferably 1 part by mass to 30 parts by mass based on 100 parts by mass of the colorant.

-Additive-
The colored layer may contain additives, if necessary, in addition to the above-mentioned components. The additive is not particularly limited, and for example, the surfactants described in paragraph 0017 of Japanese Patent No. 4502784 and paragraphs 0060 to 0071 of JP2009-237362; and the surfactants described in paragraph 0018 of Japanese Patent No. 4502784. Thermal polymerization inhibitors (also referred to as polymerization inhibitors; preferred examples include phenothiazine); and additives described in paragraphs 0058 to 0071 of JP-A No. 2000-310706.

-thickness-
The thickness of the colored layer is not particularly limited, but from the viewpoint of visibility and three-dimensional moldability, it is preferably 0.5 μm or more, more preferably 3 μm or more, and even more preferably 3 μm to 50 μm. , 3 μm to 20 μm is particularly preferred.
When there are two or more colored layers, it is preferable that each colored layer independently has a thickness within the above range.

-Method for forming colored layer-
Examples of the method for forming the colored layer include a method using a composition for forming a colored layer, a method of laminating colored films, and the like. Among these, the method of forming the colored layer is preferably a method using a composition for forming a colored layer.

A method of forming a colored layer using a colored layer forming composition includes a method of coating a colored layer forming composition to form a colored layer, for example, a method of forming a colored layer by printing a colored layer forming composition. Examples include a method of forming. Examples of printing methods include screen printing, inkjet printing, flexo printing, gravure printing, and offset printing.

The composition for forming a colored layer may contain a colorant and, if necessary, at least one of a binder resin, a dispersant, and an additive. The types of each component may be those described above for the colored layer.
The content of the coloring agent is preferably 1% by mass to 50% by mass, more preferably 5% by mass to 50% by mass, and 10% by mass based on the total solid content of the composition for forming a colored layer. % to 40% by weight is particularly preferred.
The content of the binder resin is preferably 5% by mass to 70% by mass, more preferably 10% by mass to 60% by mass, and 20% by mass based on the total solid content of the composition for forming a colored layer. % to 60% by weight is particularly preferred.
The content of the dispersant is preferably 1 part by mass to 30 parts by mass based on 100 parts by mass of the colorant.

The colored layer may be a layer formed by curing a composition for forming a colored layer, for example, a composition for forming a colored layer containing a polymerizable compound and a polymerization initiator may be used. The polymerizable compound and polymerization initiator are not particularly limited, and known polymerizable compounds and known polymerization initiators may be used. One type of polymerizable compound may be used alone, or two or more types may be used in combination. One type of polymerization initiator may be used alone, or two or more types may be used in combination.

The composition for forming a colored layer may contain an organic solvent from the viewpoint of making coating easier. The organic solvent is not particularly limited, and any known organic solvent can be used. Examples of organic solvents include alcohols, esters, ethers, ketones, and aromatic hydrocarbons. One type of organic solvent may be used alone, or two or more types may be used in combination.

The content of the organic solvent is preferably 5% by mass to 90% by mass, more preferably 30% by mass to 70% by mass, based on the total amount of the composition for forming a colored layer.

As the composition for forming a colored layer, commercially available paints such as NAX Real series, NAX Admira series, and NAX Multi series (manufactured by Nippon Paint Co., Ltd.); Rethan PG series (manufactured by Kansai Paint Co., Ltd.) may be used.

The method for preparing the composition for forming a colored layer is not particularly limited, and for example, the composition for forming a colored layer may be prepared by mixing each component such as a coloring agent. In addition, when the composition for forming a colored layer contains a pigment as a coloring agent, from the viewpoint of further increasing the uniform dispersibility and dispersion stability of the pigment, a pigment dispersion containing the pigment and a dispersant is prepared in advance, and the pigment dispersion is prepared in advance. It is preferable to prepare a composition for forming a colored layer by mixing other components with the above composition.

[Orientation layer]
The laminate may have an alignment layer. The alignment layer is used to more easily align the molecules of the cholesteric liquid crystal compound in the light reflecting portion when forming the laminate.

The alignment layer is provided by, for example, rubbing treatment with an organic compound (preferably a polymer), oblique vapor deposition of an inorganic compound, formation of a layer having microgrooves, or the like. As the alignment layer, an alignment layer in which an alignment function is produced by application of an electric field, a magnetic field, or light irradiation is also known.

The thickness of the alignment layer is not particularly limited, but is preferably 0.01 μm to 10 μm.

Depending on the type of base material and underlayer, the underlayer can be used as an alignment layer without providing a separate alignment layer.
For example, by directly subjecting the base material to alignment treatment (for example, rubbing treatment), it can be made to function as an alignment layer. An example of a base material that can be directly aligned is a layer made of polyethylene terephthalate (PET), which may be subjected to a rubbing process as described below.

Hereinafter, a rubbing treatment alignment layer and a photo alignment layer will be explained as preferred examples.

-Rubbing alignment layer-
The rubbing treatment alignment layer is formed, for example, by performing a rubbing treatment on the surface of the base to which the liquid crystal composition is applied. The rubbing treatment can be performed, for example, by rubbing the surface of a film containing a polymer as a main component in a certain direction with paper or cloth. A general method of rubbing treatment is described, for example, in "Liquid Crystal Handbook" (published by Maruzensha, October 30, 2000).

Examples of polymers for the alignment layer forming a film mainly composed of the above-mentioned polymers include methacrylate copolymers, styrene copolymers, polyolefins, and the like described in paragraph 0022 of JP-A-8-338913. Examples include polyvinyl alcohol, modified polyvinyl alcohol, poly(N-methylolacrylamide), polyester, polyimide, vinyl acetate copolymer, carboxymethyl cellulose, and polycarbonate. Moreover, the polymer for alignment layer may be a silane coupling agent. The alignment layer polymer is preferably a water-soluble polymer (for example, poly(N-methylolacrylamide), carboxymethyl cellulose, gelatin, polyvinyl alcohol, or modified polyvinyl alcohol), more preferably gelatin, polyvinyl alcohol, or modified polyvinyl alcohol, and polyvinyl alcohol. or modified polyvinyl alcohol is particularly preferred.

As a method for changing the rubbing density, the method described in "Liquid Crystal Handbook" (published by Maruzensha) can be used. The rubbing density (L) is quantified by the following formula (A).
Formula (A) L=Nl(1+2πrn/60v)
In formula (A), N is the number of rubbings, l is the contact length of the rubbing roller, r is the radius of the roller, n is the number of revolutions per minute (rpm) of the roller, and v is the stage movement speed (per second).

Methods for increasing the rubbing density include increasing the number of times of rubbing, increasing the contact length of the rubbing roller, increasing the radius of the roller, increasing the number of rotations of the roller, and decreasing the stage movement speed. can be mentioned. On the other hand, methods for lowering the rubbing density include reducing the number of rubbings, shortening the contact length of the rubbing roller, decreasing the radius of the roller, decreasing the number of rotations of the roller, and increasing the stage movement speed. One method is to do so. Moreover, the description in Japanese Patent No. 4052558 can also be referred to as the conditions for the rubbing process.

-Photo alignment layer-
Examples of the photo-alignment material used in the photo-alignment layer formed by light irradiation include JP-A Nos. 2006-285197, 2007-76839, 2007-138138, and 2007-94071. Publications, JP 2007-121721, JP 2007-140465, JP 2007-156439, JP 2007-133184, JP 2009-109831, Japanese Patent No. 3883848, and patents Azo compound described in JP-A No. 4151746; aromatic ester compound described in JP-A No. 2002-229039; photo-alignable unit described in JP-A No. 2002-265541 and JP-A No. 2002-317013. Maleimide and/or alkenyl-substituted nadimide compounds; photocrosslinkable silane derivatives described in Japanese Patent No. 4205195 and Japanese Patent No. 4205198; and Japanese Patent Application Publication No. 2003-520878, Japanese Patent No. 2004-529220, and Japanese Patent No. 4162850 Examples include photocrosslinkable polyimides, polyamides, and esters described in the above publication. Among these, the photo-alignment material is preferably an azo compound, photo-crosslinkable polyimide, polyamide, or ester.

A layer formed from a photo-alignment material is irradiated with linearly polarized light or non-polarized light to produce a photo-alignment layer.

In the present disclosure, "linearly polarized light irradiation" is an operation for causing a photoreaction in a photoalignment material. The wavelength of the light used varies depending on the photoalignment material used, and is not particularly limited as long as it is a wavelength necessary for the photoreaction. The light used for light irradiation is preferably light with a peak wavelength of 200 nm to 700 nm, more preferably ultraviolet light with a peak wavelength of 400 nm or less.

The light sources used for light irradiation include known light sources, such as tungsten lamps, halogen lamps, xenon lamps, xenon flash lamps, mercury lamps, mercury-xenon lamps, carbon arc lamps, and various lasers (for example, semiconductor lasers, (helium neon laser, argon ion laser, helium cadmium laser, or YAG laser), light emitting diodes, and cathode ray tubes.

Methods for obtaining linearly polarized light include methods using a polarizing plate (for example, an iodine polarizing plate, a dichroic dye polarizing plate, or a wire grid polarizing plate), a method using a prism-based element (for example, a Glan-Thompson prism), or a method using a Brewster angle. Examples include a method using a reflective polarizer and a method using light emitted from a polarized laser light source. Alternatively, only light of a required wavelength may be selectively irradiated using a filter, a wavelength conversion element, or the like.

When the irradiated light is linearly polarized light, a method of irradiating the light from the top or back surface of the alignment layer in a direction perpendicular to or oblique to the surface of the alignment layer can be mentioned. The incident angle of light varies depending on the photo-alignment material, but is preferably 0° to 90° (perpendicular), more preferably 40° to 90°, with respect to the alignment layer.

When using non-polarized light, the non-polarized light is irradiated obliquely from the top or back surface of the alignment layer. The angle of incidence is preferably 10° to 80°, more preferably 20° to 60°, even more preferably 30° to 50°. The irradiation time is preferably 1 minute to 60 minutes, more preferably 1 minute to 10 minutes.

[Other layers]
The laminate may have layers other than the dichroic dye layer, the layer expressing structural color, the colored layer, and the alignment layer.

Other layers include a protective layer, an adhesive layer, an easy-to-adhesion layer, an ultraviolet absorbing layer, a self-healing layer, an antistatic layer, an antifouling layer, an electromagnetic shielding layer, a conductive layer, etc., which are known layers in a laminate. Can be mentioned.

Other layers can be formed by known methods. For example, a method may be mentioned in which a composition (layer-forming composition) containing the components contained in these layers is applied in a layered manner and then dried.

<Arrangement of each layer>
The arrangement of each layer of the laminate is not limited. Each layer of the laminate may be arranged as follows. "/" indicates a layer boundary. Further, it is assumed that the left side is the viewing side. Further, depending on the purpose of the laminate, each layer may have one layer alone, or two or more layers.
(1) Dichroic dye layer/Layer that expresses structural color (2) Dichroic dye layer/Adhesive layer/Layer that expresses structural color (3) Dichroic dye layer/Layer that expresses structural color/Group Material (4) Dichroic dye layer/Adhesive layer/Layer that expresses structural color/Substrate (5) Dichroic dye layer/Layer that expresses structural color/Adhesive layer/Substrate (6) Dichroic dye Layer/Adhesive layer 1/Layer that expresses structural color/Adhesive layer 2/Substrate (7) Dichroic dye layer/Layer that expresses structural color/Adhesive layer/Colored layer (8) Dichroic dye layer/Adhesive Layer 1/Layer that expresses structural color/Adhesive layer 2/Substrate (9) Dichroic dye layer/Layer that expresses structural color/Substrate/Colored layer (10) Dichroic dye layer/Adhesive layer/Structure Layer that develops color/base material/colored layer (11) Dichroic dye layer/adhesive layer 1/layer that develops structural color/substrate/adhesive layer 2/colored layer (12) Dichroic dye layer 1/ Adhesive layer 1/layer expressing structural color/substrate 1/adhesive layer 2/dichroic dye layer 2/substrate 2
Further, when the laminate is used as a decorative film for a display, for example, the following arrangement can be mentioned.
(13) Substrate 1/dichroic dye layer/adhesive layer/layer expressing structural color/substrate 2/retardation film/display

The example of the above (10) of the laminate will be explained using FIG. 1.
FIG. 1 is a schematic cross-sectional view showing an example of the layer structure of a laminate according to the present disclosure.
The laminate 20 shown in FIG. 1 includes a colored layer 22, a base material 24 on the colored layer 22, a layer 26 that exhibits a structural color on the base material 24, and an adhesive layer on the layer 26 that develops a structural color. 28, and a dichroic dye layer 30 on the adhesive layer 28.

There are no particular limitations on the uses of the laminate according to the present disclosure, and examples include decorative films, decorative panels, electronic devices (e.g., wearable devices, and smartphones), home appliances, audio products, computers, displays, and automotive products. It can be used to decorate display devices such as Among them, the decorative film according to the present disclosure can be suitably used for decorating electronic devices (for example, wearable devices and smartphones).
Furthermore, since the laminate according to the present disclosure has excellent three-dimensional moldability, it is suitable as a decorative film for molding used in molding such as three-dimensional molding and insert molding, and is suitable as a decorative film for three-dimensional molding. It is more suitable as

<Method for manufacturing laminate>
The method for manufacturing the cleaning body according to the present disclosure is not particularly limited, and a known method may be used or the cleaning body may be manufactured by applying a known method. For example, when the layer expressing structural color is a cholesteric liquid crystal layer, a step of preparing a liquid crystal material having a base material, a liquid crystal compound oriented in a cholesteric spiral, and a liquid crystal layer containing a photosensitive chiral agent. (hereinafter also referred to as "liquid crystal material preparation step"), the liquid crystal layer is irradiated with first light to spread a portion of the photosensitive chiral agent from the surface of the liquid crystal layer to the inside in the thickness direction. It includes a step of deactivating (hereinafter also referred to as "first exposure step") and a step of curing the uncured portion by irradiating with second light (hereinafter also referred to as "second exposure step"). is mentioned as a preferable example. With the above method, it is possible to easily produce a decorative film that has a layer that exhibits a structural color that has a portion in which the helical pitch of the cholesteric liquid crystal structure changes gradually (gradation-like) in the thickness direction. can.
The above example will be described in detail below.

Further, in the example of the method for manufacturing a laminate according to the present disclosure described above, it is preferable to include a step of heating the liquid crystal layer to turn it into a cholesteric liquid crystal phase (hereinafter also referred to as "first heating step").

[Liquid crystal material preparation process]
The liquid crystal material preparation step is a step of preparing a liquid crystal material having a base material, a liquid crystal layer containing a cholesteric spirally oriented liquid crystal compound (cholesteric liquid crystal compound), and a photosensitive chiral agent.

-Base material-
As the base material, those mentioned above can be used.

-Liquid crystal layer-
The liquid crystal layer preferably contains a cholesteric liquid crystal compound that can be aligned in a cholesteric spiral and a photosensitive chiral agent, and may contain other components as necessary.

The method for preparing the liquid crystal composition is not particularly limited, and the liquid crystal composition may be prepared, for example, by a method of mixing components such as a cholesteric liquid crystal compound and a chiral agent.
As each component, those mentioned above can be suitably used.

The method for applying the liquid crystal composition to the substrate is not particularly limited, and examples include spray coating, spin coating, blade coating, dip coating, casting, roll coating, bar coating, die coating, and mist coating. method, inkjet method, dispenser method, screen printing method, letterpress printing method, and intaglio printing method.

When the liquid crystal composition contains a solvent, the liquid crystal composition may be applied to the substrate and then dried. Examples of the drying method include heating drying and reduced pressure drying. When drying by heating, the heating temperature and heating time may be adjusted as appropriate depending on the type of solvent. Further, heating drying may be performed as part of the first heating step described below.

[First heating step]
The first heating step is a step of heating the liquid crystal layer to form a cholesteric liquid crystal phase. When a cholesteric liquid crystal compound is heated, as the heating temperature increases, the cholesteric liquid crystal compound changes from a crystalline state to an oriented state, and further from an oriented state to an isotropic state. In the first heating step, by heating the liquid crystal layer containing the cholesteric liquid crystal compound, the cholesteric liquid crystal compound is brought into an oriented state, and the liquid crystal layer is made into a cholesteric liquid crystal phase in which the cholesteric liquid crystal compound is oriented.

The relationship between the change in the state of the cholesteric liquid crystal compound and the heating temperature differs depending on the type of cholesteric liquid crystal compound. Therefore, the heating temperature in the first heating step may be adjusted as appropriate depending on the type of cholesteric liquid crystal compound so that the cholesteric liquid crystal compound is in an oriented state. The heating time in the first heating step may be adjusted as appropriate depending on the heating temperature and the like. Further, the heating means is not particularly limited, and an oven, a hot plate, etc. may be used.

[First exposure step]
The first exposure step is a step of irradiating the liquid crystal layer with first light to deactivate a portion of the photosensitive chiral agent from the surface of the liquid crystal layer toward the inside in the thickness direction.
In the first exposure step, for example, the first light is irradiated from either the base material side or the surface layer side, and the light is absorbed by the photosensitive chiral agent contained in the liquid crystal layer, so that the light is absorbed on the side closer to the light source. The amount of deactivation of the photosensitive chiral agent is made larger than the amount of deactivation of the photosensitive chiral agent on the side far from the light source, preferably in the layer thickness direction, from the surface of the liquid crystal layer on the side irradiated with the first light in a gradation pattern. The amount of the above-mentioned photosensitive chiral agent that is active in the photosensitive material may be increased.
In an embodiment in which the amount of the active photosensitive chiral agent increases in a gradation form from the surface of the liquid crystal layer on the side irradiated with the first light, the amount of the photosensitive chiral agent increases by the time the liquid crystal layer is cured in the second exposure step. The helical rewinding of the cholesteric liquid crystal structure occurs in accordance with the amount, and a liquid crystal layer in which the helical pitch changes in a gradation manner is obtained.
Furthermore, in the first exposure step, the first light may be irradiated only once, or may be irradiated two or more times. When exposure is performed two or more times, the exposure conditions (for example, exposure means, exposure wavelength, exposure amount, exposure atmosphere, etc.) may be adjusted as appropriate for each exposure.

The type of first light is not particularly limited, but in consideration of the reactivity of the components contained in the liquid crystal layer, it is preferable to use ultraviolet light. Examples of ultraviolet light sources include ultra-high pressure mercury lamps, high-pressure mercury lamps, metal halide lamps, and light emission diodes (LEDs).

The wavelength range of the first light is not particularly limited, but when the first light is ultraviolet light, it is preferably 400 nm or less, more preferably 360 nm or less, and even more preferably 300 nm or less. When using light of 300 nm or less, the light absorption of the cholesteric liquid crystal compound makes it easier to control photocuring in the thickness direction. The wavelength range can be adjusted, for example, by using an optical filter, using two or more types of optical filters, or using a light source with a specific wavelength.

The exposure amount of the first light is not particularly limited, and when the first light is ultraviolet light, it is preferably 0.1 mJ/cm ² to 2,000 mJ/cm ² , for example. From the viewpoint of controlling photocuring in the in-plane direction, the parallelism of ultraviolet rays is preferably 20° or less, more preferably 10° or less.

The first exposure step is performed in a low oxygen atmosphere (oxygen concentration 1,000 ppm or less, that is, does not contain oxygen or exceeds 0 ppm and 1,000 ppm The step may be carried out in an atmosphere containing oxygen (an atmosphere containing oxygen), and more preferably carried out in an atmosphere containing oxygen (atmosphere or an atmosphere containing 1000 ppm or more and less than 21% oxygen). Since radical polymerization is inhibited by oxygen, control of photocuring in the thickness direction becomes easier.

The first exposure step is performed in a low oxygen atmosphere (preferably an oxygen concentration of 1,000 ppm or less, that is, an atmosphere containing no oxygen or more than 0 ppm and 1,000 ppm or less of oxygen) from the viewpoint of promoting hardening of the liquid crystal layer. ), and more preferably under a nitrogen atmosphere.

The first exposure step is preferably performed at a temperature of 50°C or lower, more preferably 40°C or lower, and particularly preferably performed at a temperature of 0°C or higher and 35°C or lower, from the viewpoint of maintaining the change in the helical pitch of the liquid crystal layer. .

In the first exposure step, the first light may be irradiated through a first patterning mask having a plurality of regions having different transmittances of the first light. As a result, multiple regions of the liquid crystal layer can be exposed with different exposure doses, so multiple regions with different thicknesses are formed in a single layer in the in-plane direction, and the reflectance in the in-plane direction is can be controlled all at once.
Further, in the first exposure step, the first light may be irradiated through a filter having a different transmittance depending on the wavelength. Furthermore, the filter may be a filter that adjusts the exposure amount of the first light.
For example, a mask may be used in which the transmittance of the wavelength absorbed by the photopolymerization initiator is lowered, for example, to 0%, so as not to generate polymerization initiation species from the photopolymerization initiator used.

Examples of the first patterning mask include a photomask in which a pattern is formed by etching a metal film, and a pattern printed using various printing methods (for example, printing with a laser printer or inkjet printer, gravure printing, and screen printing). Examples include photomasks. A photomask patterned by etching a metal film can be obtained, for example, by forming a metal chromium film on a quartz substrate by sputtering and then patterning the film using a photoresist.
Preferred examples of the filter include those in which a dielectric multilayer film is deposited on a transparent substrate such as glass. Further, as the filter, for example, a known bandpass filter can be used.

When the first patterning mask or filter is used to irradiate the first light, the first patterning mask or filter may be placed on the opposite side of the base material to the side having the liquid crystal layer, and May be placed on the side.

When the first patterning mask or filter is disposed on the side of the base material that has the liquid crystal layer, the first patterning mask or filter may be brought into contact with the liquid crystal layer and the first light may be irradiated, and the liquid crystal layer and the first patterning mask may be placed in contact with each other. The first light may be irradiated with a gap provided between them.

When placing the first patterning mask or filter on the opposite side of the base material to the side that has the liquid crystal layer, it is recommended to use a translucent base material because the liquid crystal layer is exposed to the first light through the base material. preferable.
Regarding the light transmittance of the base material, the transmittance of the first light is not particularly limited, but from the viewpoint of curing the liquid crystal layer more easily, the higher the transmittance is, the more preferable.

When irradiating the first light using the first patterning mask or filter, only one type of first patterning mask or filter may be used, or two or more types of the first patterning mask or filter may be used.
Further, the first patterning mask and the filter may be used together.

[Second exposure process]
The second exposure step is a step of curing the liquid crystal layer by irradiating second light.
The helical pitch of the liquid crystal layer that has changed in the first exposure step can be cured and fixed by irradiation with the second light.

In the second exposure step, not only the uncured portion but also the entire liquid crystal layer may be exposed. For example, the second light may be irradiated from the side of the base material having the liquid crystal layer.

The type of second light is not particularly limited, but in consideration of the reactivity of components that may be included in the liquid crystal compound, it is preferable to use ultraviolet light. Examples of ultraviolet light sources include ultra-high pressure mercury lamps, high-pressure mercury lamps, metal halide lamps, and light emitting diodes (LEDs).

The wavelength range of the second light is not particularly limited, and for example, light in the wavelength range of 250 nm to 400 nm can be used. The wavelength range can be adjusted, for example, by using an optical filter, using two or more types of optical filters, or using a light source with a specific wavelength.

The exposure amount of the second light is not particularly limited, and when the second light is ultraviolet light, it is preferably 5 mJ/cm ² to 2,000 mJ/cm ² , for example.

The second exposure step is performed in a low oxygen atmosphere (preferably an oxygen concentration of 1,000 ppm or less, that is, an atmosphere that does not contain oxygen or contains more than 0 ppm and 1,000 ppm or less of oxygen) in order to accelerate curing. It is preferable that the reaction be carried out under a nitrogen atmosphere, and more preferably that it be carried out under a nitrogen atmosphere.

The second exposure step is preferably performed at a temperature of 50°C or lower, more preferably 40°C or lower, and preferably performed at a temperature of 0°C or higher and 35°C or lower, from the viewpoint of maintaining the change in the helical pitch of the liquid crystal layer until curing. Particularly preferred.

[Dichroic dye layer formation process]
The method for manufacturing a laminate according to the present disclosure includes a dichroic dye layer forming step of forming a dichroic dye layer.
As mentioned above, the dichroic dye layer forming step is a step of applying and drying the composition for forming a dichroic dye layer on the layer expressing a structural color, and polymerizing it by light exposure, if necessary. It is preferable.
The conditions for polymerization by light exposure are preferably the same as in the second exposure step.

[Other processes]
The method for manufacturing a decorative film according to the present disclosure may include steps other than the above steps, as necessary. Other steps include, for example, a step of peeling off the base material from a decorative film produced in an embodiment that includes the base material, and a decorated film that does not include the base material can be produced.
Further, other steps include a colored layer forming step, an alignment layer forming step, and another layer forming step. The details and formation method of the colored layer and alignment layer are as described above. Further, the details of the other layers are as described above, and known methods may be used to form the other layers.

<Decorative films, articles, decorative panels, display devices>
The laminate according to the present disclosure can be used for various purposes, and for example, the laminate can be molded and used as a molded product.
The decorative film according to the present disclosure includes the laminate according to the present disclosure, and may be formed by molding the laminate according to the present disclosure.
The article according to the present disclosure is an article provided with the laminate according to the present disclosure.
Such a laminate can be provided in a variety of articles.
Such articles include, for example, electronic devices such as smartphones, mobile phones, and tablets, automobiles, electrical appliances, packaging containers, etc., and can be particularly preferably used for electronic devices. As the electronic device, display devices such as a display, a smartphone, a mobile phone, and a tablet are more preferably mentioned. Among these, it can be particularly suitably used for ordinary displays or displays in display devices such as smartphones, home appliances, audio products, computers, and in-vehicle products.
Moreover, when using the laminate according to the present disclosure in a display device such as a display or a smartphone, a retardation film may be provided between the laminate according to the present disclosure and a display member such as a display.
As the retardation film, known ones can be used.

The means for molding the laminate according to the present disclosure to obtain a molded body is not particularly limited, and may be, for example, a known method such as three-dimensional molding or insert molding. Furthermore, the means for applying the laminate according to the present disclosure to an article is not particularly limited, and any known method may be used as appropriate depending on the type of article.

A decorative panel according to the present disclosure includes a decorative film according to the present disclosure.
The shape of the decorative panel is not limited. The shape of the decorative panel may be determined depending on the application, for example. The decorative panel may be, for example, flat. Further, the decorative panel may have a curved surface.
Decorative panels can be used, for example, for the interior and exterior of various articles. Articles include those mentioned above (eg, electronic devices, automobiles, and electrical products).

The decorative panel can be manufactured, for example, by bonding the surface of the decorative film on the layer side that exhibits the structural color and the surface of the member that will become the surface layer portion of the decorative panel. Examples of the member that forms the surface layer of the decorative panel include a glass panel. For example, the above-mentioned adhesive layer can be used to bond the decorative film and the member that will become the surface layer of the decorative panel. For example, a molded decorative film may be used alone as a decorative panel without combining the decorative film and other members.
A display device according to the present disclosure is a display device including a decorative panel according to the present disclosure.
Examples of display devices include displays, smartphones, mobile phones, tablets, and the like.

Hereinafter, the present disclosure will be explained in detail with reference to Examples. However, the present disclosure is not limited to the following examples.

<Example 1>
[Preparation of base material]
As a base material, a polyethylene terephthalate (PET) film (Cosmoshine (registered trademark) A4160, manufactured by Toyobo Co., Ltd.) having a thickness of 100 μm and having an easily adhesive layer on one side was prepared and used as the transparent base material 1.

[Formation of undercoat layer 1]
An undercoat layer 1 coating solution having the following composition was continuously applied onto the surface of the transparent substrate 1 without an easy-adhesion layer using a #14 wire bar. It was dried with warm air at 60°C for 60 seconds and then with warm air at 100°C for 120 seconds.

-Composition of undercoat layer 1 coating liquid-
The following modified polyvinyl alcohol (the numbers in the lower right brackets represent mass %): 10 parts by mass Water: 371 parts by mass Methanol: 119 parts by mass Glutaraldehyde: 0.5 parts by mass Photopolymerization initiator (Irgacure 2959, IGM Resins ): 0.3 part by mass

[Formation of layer 1 with structural color (cholesteric liquid crystal layer 1, red-IR pattern)]
Liquid crystal composition 1 having the composition described below was prepared.

-Composition of liquid crystal composition 1-
Liquid crystal compound having the structure shown below 1: 80 parts by mass Liquid crystal compound having the structure shown below 2: 10 parts by mass Compound 3 having the structure shown below: 10 parts by mass Chiral agent 1 (photosensitive chiral agent, shown below) structure): 3.75 parts by mass Chiral agent 2 (LC-756: manufactured by BASF): 3.75 parts by mass Photoinitiator (IRGACURE127: manufactured by BASF): 0.5 parts by mass Surfactant 1 (Compound having the structure shown below): 0.64 parts by mass Organic solvent 1 (methyl ethyl ketone): 205 parts by mass Organic solvent 2 (cyclohexanone): 10 parts by mass

Liquid crystal compound 1: The following compound

Liquid crystal compound 2: The following compound

Compound 3: The following compound

Chiral agent 1: The following compound

Surfactant 1: The following compound

Liquid crystal composition 1 was applied to the surface of transparent substrate 1 with undercoat layer 1 using a #3 wire bar coater. Thereafter, it was dried at 80°C for 120 seconds, and then heated to 25°C using an ultraviolet irradiation device using a metal halide lamp (MAL625NAL, manufactured by GS Yuasa Co., Ltd.), and passed through a bandpass filter 1 having the following characteristics into Table 1. Ultraviolet rays were irradiated with the exposure amount adjusted so that the wavelength was as described. During this irradiation, a film printed with black ink was used as a mask on a polyethylene terephthalate (PET) film so that two different wavelength reflection areas were created between the liquid crystal layer and the ultraviolet irradiation device as shown in Table 1. mediated.
Thereafter, in an atmosphere with an oxygen concentration of 5% by mass or less, 90 mJ/cm ² of ultraviolet rays are irradiated at 120°C using an ultraviolet irradiation device using a metal halide lamp (MAL625NAL, manufactured by GS Yuasa Co., Ltd.). By curing the layer and further performing similar exposure at a low oxygen concentration (1,000 ppm or less), the liquid crystal layer is completely cured, and a layer that expresses structural color has two different wavelength reflection regions. 1 was formed.
The bandpass filter 1 has a dielectric multilayer film deposited on a glass substrate (TEMPAX Float t2.0 mm manufactured by SHOTT), and has a transmittance of 0% for wavelengths of 350 nm to 450 nm or more, and an average transmittance of 70% for wavelengths of 310 nm to 330 nm. ~75%.

[Preparation of base material S-1]
(Production of polyimide powder)
After adding 832 g of N,N-dimethylacetamide (DMAc) to a 1 L reactor equipped with a stirrer, nitrogen injector, dropping funnel, temperature controller, and condenser under a nitrogen stream, the temperature of the reactor was increased to 25°C. It was set to ℃. To this, 64.046 g (0.2 mol) of bistrifluoromethylbenzidine (TFDB) was added and dissolved. While maintaining the resulting solution at 25°C, 31.09 g (0.07 mol) of 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride (6FDA) and biphenyltetracarboxylic dianhydride were added. 8.83 g (0.03 mol) of BPDA was added thereto, and the mixture was stirred for a certain period of time to react. Thereafter, 20.302 g (0.1 mol) of terephthaloyl chloride (TPC) was added to obtain a polyamic acid solution with a solid content concentration of 13% by mass. Next, 25.6 g of pyridine and 33.1 g of acetic anhydride were added to this polyamic acid solution, stirred for 30 minutes, further stirred at 70° C. for 1 hour, and then cooled to room temperature. 20 L of methanol was added thereto, and the precipitated solid content was filtered and pulverized. Thereafter, it was dried in vacuum at 100° C. for 6 hours to obtain 111 g of polyimide powder.

(Preparation of base material S-1)
100 g of the above polyimide powder was dissolved in 670 g of N,N-dimethylacetamide (DMAc) to obtain a 13% by mass solution. The obtained solution was cast onto a stainless steel plate and dried with hot air at 130°C for 30 minutes. After that, the film was peeled off from the stainless steel plate and fixed to the frame with pins, and the frame with the film fixed was placed in a vacuum oven and heated for 2 hours while gradually increasing the heating temperature from 100°C to 300°C. It was cooled to After the cooled film was separated from the frame, it was further heat treated at 300° C. for 30 minutes as a final heat treatment step to obtain a 50 μm thick base material S-1 made of polyimide film.

[Formation of dichroic dye layer 1]
Dichroic dye layer forming composition 1 was applied onto the surface of the substrate S-1 using a bar number selected so that the thickness after drying would be the thickness listed in Table 1. Thereafter, it was dried at 180°C for 20 seconds, and then rapidly cooled to 20°C. Next, after aging at 75°C for 30 seconds, it was rapidly cooled to 20°C. Thereafter, 500 mJ/cm ² of ultraviolet rays were irradiated with an ultraviolet irradiation device using a metal halide lamp (MAL625NAL, manufactured by GS Yuasa Co., Ltd.) at 40°C in an atmosphere with an oxygen concentration of 5% by mass or less. A color pigment layer 1 was formed.

- Dichroic dye layer forming composition 1 (dichroic dye concentration 6.6% by mass) -
Dichroic dye 1: 5.07 parts by mass Liquid crystal compound 2: 45.3 parts by mass Liquid crystal compound 3: 23 parts by mass Photopolymerization initiator (ADEKA Arkles NCI-730, manufactured by ADEKA Corporation) Chloroform 3% by mass Solution: 39 parts by mass 1% by mass solution of surfactant 3 in chloroform: 39 parts by mass 2% by mass solution of alignment agent 1 in chloroform: 41 parts by mass 2% by mass solution of chloroform in alignment agent 2: 41 parts by mass Organic solvent 1 (chloroform ): 758 parts

Dichroic dye 1: The following compound

Liquid crystal compound 2: The following compound (The number to the right of the parentheses representing the structural unit represents the mass ratio, and the number to the right of the parentheses of the ethylene oxide unit represents the number of repetitions.)

Liquid crystal compound 3: The following compound

Surfactant 3: The following compound (The number at the bottom right of the parentheses representing the structural unit represents the mass ratio.)

Aligning agent 1: The following compound

Aligning agent 2: The following compound

[Formation of laminate]
Using an adhesive sheet for optical films (M3D49, manufactured by Bidate Imaging Co., Ltd.), the formed dichroic dye layer 1 and layer 1 expressing structural color were laminated to form a laminate (layer structure: base material S). -1/dichroic dye layer 1/adhesive layer/layer expressing structural color 1/transparent base material 1) was prepared.

<Example 2>
A laminate of Example 2 was produced in the same manner as Example 1 except that the thickness of the dichroic dye layer was changed to 1.8 μm.

<Example 3>
The laminate of Example 3 was prepared in the same manner as in Example 1, except that the layer expressing structural color was produced without using a mask, and Layer 1 having structural color was changed to Layer 2 having structural color. Created.

<Example 4>
A laminate (layer structure: base material S-1/dichroic dye layer 1/Adhesive layer/Dielectric multilayer film/Transparent base material 1) was produced. The dielectric multilayer film was produced by adjusting the film thickness so that the reflection wavelength was the reflection peak wavelength shown in Table 1, with reference to Example 1 of JP-A-2008-200861.

<Comparative example 1>
A laminate of Comparative Example 1 was produced in the same manner as in Example 1, except that no dichroic dye layer was formed (layer structure: base material S-1/adhesive layer/layer 1 expressing structural color). /Transparent base material 1).

<Comparative example 2>
A laminate (layer structure: base material S-1/adhesive layer/layer 1 expressing structural color/transparent base material 1) was produced in the same manner as in Example 3, except that the dichroic dye layer was not formed. did.

<Comparative example 3>
A laminate (layer structure: base material S-1/adhesive layer/dielectric multilayer film/transparent base material 1) was produced in the same manner as in Example 4, except that the dichroic dye layer was not formed.

[Color measurement (viewing angle dependency evaluation)]
A measuring device using an integrating sphere measures the spectral reflectance of the object to be measured and the spectral reflectance of a completely diffuse reflecting surface, calculates a ^* and b ^* based on the following formula, and calculates the following from a ^* and b ^* . The hue angle h was calculated based on Equation 2.

Hue angle h=tan ^-1 (b ^* /a ^* ) Equation 2

At this time, an SR-3 (spectral radiance meter, manufactured by Topcon Technohouse Co., Ltd.) was used as the sensor, and the sample was measured at an angle of declination of 5° and 55°. Evaluation was made based on the difference (°) in hue angle from an angle of 55°.
Note that the above 5° and 55° are angles with respect to the normal direction of the laminate.

[Measurement of 55° absorption spectrum of dichroic dye layer]
Using an automatic absolute reflectance measuring unit ARMN-735 and a spectrophotometer V-670 EX (manufactured by JASCO Corporation), the absorbance was measured from a direction inclined at an angle of 55° with respect to the normal direction of the laminate. , from which the transmittance was calculated.

[Measurement of reflection wavelength of layer expressing structural color]
Using an automatic absolute reflectance measurement unit ARMN-735 and a spectrophotometer V-670 EX (manufactured by JASCO Corporation), reflections from directions inclined at 5° and 55° with respect to the normal direction of the laminate were measured. The spectra were measured, and the peak tops were defined as the reflection wavelength (viewing angle 85°) and the reflection wavelength (viewing angle 35°), respectively.

[Measurement of peak overlap]
Using an automatic absolute reflectance measurement unit ARMN-735 and a spectrophotometer V-670 EX (manufactured by JASCO Corporation), the viewing angle was -90° to +90° (in this case, the normal direction of the laminate was 0°). ), the overlap of the wavelength bands of the absorption peak at absorption peak wavelength A in the absorption area and the absorption peak at reflection peak wavelength B in the reflection area was measured. As shown in Figure 2, the wavelength band overlap is between the wavelength band B of the half-width of the absorption peak of the dichroic dye layer at a viewing angle of 55° and the reflection peak of the layer expressing structural color at a viewing angle of 55°. Evaluation was made using a wavelength band C that overlaps the wavelength band A of the half-width.

The evaluation results are summarized in Table 1.

As shown in Table 1, the laminates of Examples had less viewing angle dependence than the laminates of Comparative Examples.

The disclosure of Japanese Patent Application No. 2022-040583 filed on March 15, 2022 is incorporated herein by reference in its entirety. All documents, patent applications, and technical standards mentioned herein are incorporated by reference to the same extent as if each individual document, patent application, and technical standard were specifically and individually indicated to be incorporated by reference. Incorporated herein by reference.

Claims

a dichroic pigment layer containing a dichroic pigment;
It has a layer that expresses a structural color,
The dichroic dye layer has an absorption peak wavelength A in a wavelength range of 400 nm or more and 700 nm or less,
The layer expressing the structural color has a reflection peak wavelength B in a wavelength range of 400 nm or more and 700 nm or less,
A laminate having a wavelength band in which the absorption peak at wavelength A and the reflection peak at wavelength B at least partially overlap each other when viewed from the side of the dichroic dye layer at a viewing angle of -90° to 90°. .
The laminate according to claim 1, wherein the layer expressing structural color is a layer made of a dielectric multilayer film or a cholesteric liquid crystal layer.
The laminate according to claim 1 or 2, wherein the angle θ between the central axis of transmittance of the dichroic dye layer and the normal direction of the laminate is 0° to 45°.
The laminate according to any one of claims 1 to 3, wherein the layer expressing the structural color has two or more reflective regions having different selective reflection wavelengths.
The laminate according to any one of claims 1 to 4, wherein the dichroic dye layer is a layer formed by polymerizing at least a liquid crystal compound having a polymerizable group.
The laminate according to any one of claims 1 to 5, wherein the layer expressing structural color is a cholesteric liquid crystal layer.
The laminate according to claim 6, wherein the cholesteric liquid crystal layer contains a chiral agent having a site that isomerizes upon irradiation with light.
a dichroic pigment layer containing a dichroic pigment;
a layer that exhibits structural color and has two or more reflective regions with different selective reflection wavelengths;
A laminate having.
The laminate according to claim 8, wherein the angle θ between the transmittance center axis of the dichroic dye layer and the normal direction of the laminate is 0° to 45°.
A decorative film comprising the laminate according to any one of claims 1 to 9.
An article comprising the laminate according to any one of claims 1 to 9.
A decorative panel comprising the decorative film according to claim 10.
A display device comprising the decorative panel according to claim 12.