JP7646417B2 - Decorative sheet for molding, moldings and electronic devices - Google Patents

Description

This disclosure relates to decorative sheets for molding, molded products, and electronic devices.

For example, the following technologies are known as technologies related to decorative materials that utilize a cholesteric liquid crystal phase. Patent Document 1 discloses a cholesteric resin laminate having a substrate, an intermediate layer, and a cholesteric resin layer in this order, in which the difference in the central wavelength of the reflection band of the cholesteric resin layer before and after heating the laminate at 130°C for 8 hours is 50 nm or less. Patent Document 2 discloses a molding decorative film having a cholesteric liquid crystal layer on a substrate, the cholesteric liquid crystal layer being a layer formed by curing a liquid crystal composition containing 25% by mass or more of a cholesteric liquid crystal compound having one ethylenically unsaturated group or one cyclic ether group relative to the total solid content of the liquid crystal composition.

International Publication No. 2017/018468 International Publication No. 2020/122235

A decorative material may be molded when decorating an object or before decorating the object. During the molding process, the decorative material needs to be deformed to follow the shape of a three-dimensional object (e.g., a mold and an object to be decorated), so the moldability of the decorative material tends to depend on the stretchability of the decorative material. However, in a study on the moldability of a decorative material, it was revealed that, for example, while the moldability of the decorative material is improved by reducing the crosslink density of the cholesteric liquid crystal layer, the color of the decorative material (including the hue, saturation, and brightness of the decorative material as perceived by the observer's eyes; the same applies below) is likely to change in a thermal environment. For these reasons, it is necessary to achieve both moldability and thermal durability (the property of the decorative material that the color does not change easily in a thermal environment; the same applies below).

The present disclosure aims to provide a moldable decorative sheet that has excellent moldability and thermal durability, a molded product obtained by molding the moldable decorative sheet, and an electronic device that includes the molded product.

Means for solving the above problems include the following aspects.
<1> A decorative sheet for molding comprising, in this order, a cholesteric liquid crystal layer, an intermediate layer in contact with the cholesteric liquid crystal layer, and an adhesive layer in contact with the intermediate layer, wherein the intermediate layer comprises a polymer having an SP value of 23.0 ^{MPa 1/2} or more, a ratio of a total amount of the polymer to a total amount of solids of the intermediate layer is 60 mass% or more, and a breaking elongation measured in an environment of 80°C is 10% or more.
<2> The moldable decorative sheet according to <1>, wherein the polymer comprises at least one selected from the group consisting of polyvinyl alcohol and modified polyvinyl alcohol.
<3> The moldable decorative sheet according to <1> or <2>, wherein the polymer comprises a modified polyvinyl alcohol having at least one selected from the group consisting of an ethylenically unsaturated group and a cyclic ether group.

<4> The moldable decorative sheet according to any one of <1> to <3>, wherein the polymer contains a modified polyvinyl alcohol represented by the following formula (I):

In formula (I), L ¹¹ represents a linking group containing an amide bond, an ether bond, a urethane bond, or an ester bond; R ¹¹ represents an alkylene group or an alkyleneoxy group; L ¹² represents a single bond or a linking group; Q ¹¹ represents an ethylenically unsaturated group or a cyclic ether group; on the premise that x1+y1+z1=100 mol%, x1 represents 10 mol% to 99.9 mol%, y1 represents 0.01 mol% to 80 mol%, z1 represents 0 mol% to 70 mol%, k is 0 or 1, and h is 0 or 1.

<5> The moldable decorative sheet according to <4>, wherein y1 is 0.5 mol % to 15 mol %.
<6> The moldable decorative sheet according to any one of <1> to <5>, wherein the central wavelength of the reflection band is 350 nm to 1,200 nm.
<7> The moldable decorative sheet according to any one of <1> to <6>, wherein the absolute value of the difference between the reflection band center wavelength measured before a heating test for 500 hours in an 80°C environment and the reflection band center wavelength measured after a heating test for 500 hours in an 80°C environment is 0 nm to 15 nm.
<8> The moldable decorative sheet according to any one of <1> to <7>, wherein the absolute value of the difference between the reflection band center wavelength measured before a heating test for 500 hours under an environment of 60°C and 90% RH and the reflection band center wavelength measured after a heating test for 500 hours under an environment of 60°C and 90% RH is 0 nm to 15 nm.
<9> A molded product obtained by molding the moldable decorative sheet according to any one of <1> to <8>.
<10> An electronic device comprising the molded article according to <9>.

The present disclosure provides a moldable decorative sheet having excellent moldability and thermal durability, a molded product obtained by molding the moldable decorative sheet, and an electronic device including the molded product.

The following describes in detail the embodiments of the present disclosure. The present disclosure is not limited to the following embodiments. The following embodiments may be modified as appropriate within the scope of the purpose of the present disclosure.

In this disclosure, a numerical range indicated using "~" indicates a range that includes the numerical values before and after "~" as the lower and upper limits, respectively. In the numerical ranges described in stages in this disclosure, the upper or lower limit value described in a certain numerical range may be replaced with the upper or lower limit value of another numerical range described in stages. In addition, in the numerical ranges described in this disclosure, the upper or lower limit value described in a certain numerical range may be replaced with a value shown in the examples.

In this disclosure, when multiple substances corresponding to each component are present in the composition, the amount of each component in the composition means the total amount of the multiple substances present in the composition, unless otherwise specified.

In this disclosure, the term "process" includes not only independent processes, but also processes that cannot be clearly distinguished from other processes as long as the intended purpose of the process is achieved.

In this disclosure, "mass %" and "weight %" are synonymous, and "parts by mass" and "parts by weight" are synonymous.

In this disclosure, "solids" refers to components other than solvents. Liquid components that do not fall under the category of solvents are considered to be solids.

In this disclosure, groups (atomic groups) that are not marked with the terms "substituted" or "unsubstituted" include groups that have a substituent and groups that do not have a substituent. For example, an "alkyl group" includes alkyl groups that have a substituent and alkyl groups that do not have a substituent.

In this disclosure, a combination of two or more preferred aspects is a more preferred aspect.

Unless otherwise specified, the weight average molecular weight (Mw) and number average molecular weight (Mn) in this disclosure are molecular weights detected by a gel permeation chromatography (GPC) analyzer using columns of TSKgel GMHxL, TSKgel G4000HxL, or TSKgel G2000HxL (all product names manufactured by Tosoh Corporation) in THF (tetrahydrofuran) as a solvent and a differential refractometer, and converted using polystyrene as a standard substance.

In this disclosure, "(meth)acrylate" includes acrylate and methacrylate.

In this disclosure, "(meth)acrylic" includes acrylic and methacrylic.

In this disclosure, "(meth)acryloyl" includes acryloyl and methacryloyl.

In this disclosure, "SP value" means solubility parameter.

<Decorative sheet for molding>
The moldable decorative sheet according to one embodiment of the present disclosure includes a cholesteric liquid crystal layer, an intermediate layer in contact with the cholesteric liquid crystal layer, and an adhesive layer in contact with the intermediate layer, in this order, the intermediate layer includes a polymer having an SP value of 23.0 MPa ^1/2 or more, the ratio of the total amount of the polymer to the total amount of solids of the intermediate layer is 60 mass% or more, and the breaking elongation measured in an environment of 80°C is 10% or more. According to the above embodiment, a moldable decorative sheet having excellent moldability and heat durability is provided. Hereinafter, the "polymer having an SP value of 23.0 MPa ^1/2 or more" may be referred to as a "specific polymer".

The reason why the present disclosure provides a moldable decorative sheet with excellent moldability and thermal durability is presumed to be as follows. In the study of the moldability of a decorative material containing a cholesteric liquid crystal layer, for example, (1) a method of reducing the crosslink density of the cholesteric liquid crystal layer and (2) a method of contacting the cholesteric liquid crystal layer and the adhesive layer in the moldable decorative sheet have been attempted. However, in the above-mentioned methods, when the crosslink density of the cholesteric liquid crystal layer is reduced, the low molecular weight compound contained in the cholesteric liquid crystal layer is likely to move to the adhesive layer in a thermal environment. When the low molecular weight compound moves as described above, the helical pitch in the cholesteric liquid crystal phase changes, and the color of the decorative material changes. On the other hand, in the moldable decorative sheet according to one embodiment of the present disclosure, an intermediate layer containing 60% or more by mass of a specific polymer is disposed between the cholesteric liquid crystal layer and the adhesive layer. Since many of the low molecular weight compounds in the cholesteric liquid crystal layer exhibit a polarity lower than that of the specific polymer, the specific polymer in the intermediate layer suppresses the migration of the low molecular weight compounds contained in the cholesteric liquid crystal layer to the adhesive layer through the intermediate layer in a thermal environment, and as a result, suppresses the color of the molded decorative sheet from changing in a thermal environment. Furthermore, in the molded decorative sheet according to one embodiment of the present disclosure, the breaking elongation measured in an environment of 80°C is 10% or more, thereby improving the stretchability and also improving the ability to follow the shape of a three-dimensional object (e.g., a mold and an object to be decorated). Therefore, according to one embodiment of the present disclosure, a molded decorative sheet with excellent moldability and heat durability is provided.

(Elongation at break)
In the moldable decorative sheet according to one embodiment of the present disclosure, the breaking elongation measured in an environment of 80° C. is 10% or more. When the breaking elongation is 10% or more, the extensibility is improved, and as a result, the moldability is improved. From the viewpoint of improving the moldability, the breaking elongation measured in an environment of 80° C. is preferably 15% or more, and more preferably 20% or more. For the purpose of moldability, the upper limit of the breaking elongation is not limited. From the viewpoint of controlling the thickness of the moldable decorative sheet before and after molding, the breaking elongation measured in an environment of 80° C. may be 300% or less or 200% or less.

In the present disclosure, the breaking elongation is measured by the following method. The molded decorative sheet is cut into a size of 10 mm x 50 mm to prepare a sample. A tensile test is performed on the obtained sample at a speed of 1,000 mm/sec in an atmosphere of 80 ° C. using a thermo-tensilon (RTF-1310 manufactured by A & D Co., Ltd. and a thermostatic tester TKC). The maximum value that the sample can be stretched without breaking is measured, and the obtained value is adopted as the breaking elongation. In addition, when the molded decorative sheet includes a peelable substrate as the outermost layer, it is preferable to peel off the peelable substrate arranged as the outermost layer before cutting the molded decorative sheet. Furthermore, when peeling off the peelable substrate arranged as the outermost layer, for the convenience of measuring the breaking elongation, the peelable substrate arranged as the outermost layer may be replaced with a substrate having high extensibility (for example, a substrate made of a resin such as acrylic, polyethylene, polypropylene, polyurethane, or amorphous polyethylene terephthalate). The breaking elongation measured using a sample that does not include a peelable substrate (including a sample in which a substrate with high extensibility is used instead of a peelable substrate) is considered to be the breaking elongation of the molding decorative sheet.

(Reflection band center wavelength)
The mold-forming decorative sheet according to an embodiment of the present disclosure preferably has selective reflectivity in a specific wavelength range. In the mold-forming decorative sheet according to an embodiment of the present disclosure, the reflection band center wavelength is preferably 350 nm to 1,200 nm, more preferably 380 nm to 950 nm, and even more preferably 380 nm to 780 nm.

In the present disclosure, the central wavelength of the reflection band of the decorative sheet for molding is measured by the following method. A spectrophotometer (e.g., UV-3100PC, manufactured by Shimadzu Corporation) is used to measure the transmission spectrum of the decorative sheet for molding. The intensity of the obtained transmittance spectrum is inverted and treated as the reflection spectrum of the decorative sheet for molding. Using the reflection spectrum, the maximum value of the reflectance is taken as R _max (%), and the average value of two wavelengths showing the half-value reflectance R ^1/2 (%) expressed by the following formula is taken as the central wavelength of the reflection band.
Formula: R ^1/2 = R _max ÷2

In the moldable decorative sheet according to one embodiment of the present disclosure, the absolute value of the difference between the reflection band central wavelength measured before a 500-hour heating test in an 80°C environment and the reflection band central wavelength measured after a 500-hour heating test in an 80°C environment is preferably 0 nm to 15 nm, more preferably 0 nm to 10 nm, and even more preferably 0 nm to 5 nm. The heating test is carried out using an incubator (e.g., SH-221 manufactured by Espec Corporation).

The absolute value of the difference between the reflection band central wavelength measured before a 500-hour heating test in an environment of 60°C and 90% RH and the reflection band central wavelength measured after a 500-hour heating test in an environment of 60°C and 90% RH is preferably 0 nm to 15 nm, more preferably 0 nm to 10 nm, and even more preferably 0 nm to 5 nm. The heating test is carried out using a thermo-hygrostat (e.g., SH-221 manufactured by Espec Corporation). "% RH" represents relative humidity.

(Thickness)
From the viewpoint of moldability and ease of handling, the thickness of the moldable decorative sheet according to one embodiment of the present disclosure is preferably 25 μm to 300 μm, more preferably 30 μm to 200 μm, and even more preferably 40 μm to 150 μm.

In this disclosure, the thickness of the moldable decorative sheet is represented by the arithmetic average of the thicknesses of the moldable decorative sheet measured at three points based on a cross-sectional image obtained using a scanning electron microscope (e.g., model "S-5500", manufactured by Hitachi High-Tech Corporation). A sample is obtained by cutting the moldable decorative sheet to a size of 5 mm wide x 2 mm long, embedding the obtained test piece in epoxy resin, and then cutting the moldable decorative sheet in the thickness direction using a microtome (e.g., product name "RM2265", manufactured by Leica). In this disclosure, the thickness of each component of the moldable decorative sheet is also measured by a method similar to the above-mentioned method.

(Cholesteric Liquid Crystal Layer)
The moldable decorative sheet according to one embodiment of the present disclosure includes a cholesteric liquid crystal layer. The cholesteric liquid crystal layer is a layer that includes a cholesteric liquid crystal phase. The cholesteric liquid crystal phase is confirmed by known means (e.g., a polarizing microscope and a scanning electron microscope).

It is known that a cholesteric liquid crystal phase is formed by arranging multiple liquid crystal compounds in a spiral shape. The orientation state of the liquid crystal compounds in the cholesteric liquid crystal phase may be an orientation state that reflects right-handed circularly polarized light, left-handed circularly polarized light, or both right-handed and left-handed circularly polarized light. The orientation state of the liquid crystal compounds in the cholesteric liquid crystal phase may be fixed. The orientation state of the liquid crystal compounds is fixed, for example, by polymerization or crosslinking of the liquid crystal compounds. The liquid crystallinity of the liquid crystal compounds may be lost in some or all of the liquid crystal compounds whose orientation state is 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 color change of the decorative material depending on the observation 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 compound added. The relationship between the helical structure and the chiral compound is described, for example, in "Fujifilm Research Report, No. 50 (2005), pp. 60-63." The helical pitch may also be adjusted by conditions such as temperature, illuminance, and exposure time when fixing the cholesteric liquid crystal phase.

The moldable decorative sheet according to one embodiment of 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 moldable decorative sheet 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 ranges described above.

The components of the cholesteric liquid crystal layer are selected from known cholesteric liquid crystal layer components, for example, depending on the desired properties of the cholesteric liquid crystal layer. Examples of the components of the cholesteric liquid crystal layer include the 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 an oligomer) 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 a "liquid crystal composition"). The following is a detailed description of the liquid crystal composition.

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 (i.e., cholesteric liquid crystal compounds) depending on the characteristics of the desired cholesteric liquid crystal layer. Examples of liquid crystal compounds include liquid crystal compounds having at least one type selected from the group consisting of ethylenically unsaturated groups and cyclic ether groups. From the viewpoint of improving moldability, it is preferable that the liquid crystal compound includes a cholesteric liquid crystal compound having one ethylenically unsaturated group or one cyclic ether group (hereinafter, sometimes referred to as a "specific liquid crystal compound").

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, more preferably a (meth)acryloyloxy group or a (meth)acrylamide group, even more preferably a (meth)acryloyloxy group, and particularly preferably 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, it is preferable that the liquid crystal compound contains a liquid crystal compound having one ethylenically unsaturated group. Furthermore, it is preferable that the ratio of the total amount of the liquid crystal compound having one ethylenically unsaturated group to the total amount of solids in the liquid crystal composition is 25 mass% or more.

When the number of ethylenically unsaturated groups contained in a molecule is one, the specific liquid crystal compound may have a functional group other than the ethylenically unsaturated group (e.g., a polymerizable 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 a molecule is one, the specific liquid crystal compound may have a functional group other than the cyclic ether group (e.g., a polymerizable 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 preferably includes a liquid crystal compound having one ethylenically unsaturated group and no cyclic ether group, a liquid crystal compound having one cyclic ether group and no ethylenically unsaturated group, or a liquid crystal compound having one ethylenically unsaturated group and one cyclic ether group. Furthermore, the liquid crystal compound preferably includes a liquid crystal compound having one ethylenically unsaturated group and no cyclic ether group.

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

Preferred rod-shaped 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-substituted phenylpyrimidine compounds, phenyldioxane compounds, tolane compounds, and alkenylcyclohexylbenzonitrile compounds. The rod-shaped liquid crystal compounds are not limited to low molecular weight compounds, and may be polymeric compounds.

Rod-shaped liquid crystal compounds are described, for example, in "Makromol. Chem., Vol. 190, p. 2255 (1989)" and "Advanced Materials 5, p. 107 (1993)", U.S. Pat. No. 4,683,327, U.S. Pat. No. 5,622,648, U.S. Pat. No. 5,770,107, WO 95/22586, WO 95/24455, WO 97/00600, WO 98/23580, WO 98/52905, JP-A-1-272551, JP-A-6-16616, JP-A-7-110469, JP-A-11-80081, and JP-A-2001-328973 may be selected from compounds having one ethylenically unsaturated group and compounds having one cyclic ether group. Preferred rod-shaped liquid crystal compounds may be selected from compounds having one ethylenically unsaturated group and compounds having one cyclic ether group, for example, as described in JP-T-11-513019 and JP-A-2007-279688.

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

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

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

From the viewpoint of improving stretchability and thermal durability, the ratio of the total amount of the specific liquid crystal compound to the total amount of solids in 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. Furthermore, the ratio of the total amount of the specific liquid crystal compound to the total amount of solids in the liquid crystal composition is preferably 60% by mass to 99% by mass, and more preferably 80% by mass to 98% by mass.

The liquid crystal composition may contain other liquid crystal compounds. Other liquid crystal compounds refer to liquid crystal compounds other than the specific liquid crystal compound. Examples of other liquid crystal compounds include liquid crystal compounds that have no ethylenically unsaturated groups and no cyclic ether groups, liquid crystal compounds that have two or more ethylenically unsaturated groups and no cyclic ether groups, liquid crystal compounds that have two or more cyclic ether groups and no ethylenically unsaturated groups, and liquid crystal compounds that have two or more ethylenically unsaturated groups and two or more cyclic ether groups.

From the viewpoint of suppressing changes in reflectance and color after molding, the other liquid crystal compound is preferably at least one selected from the group consisting of liquid crystal compounds having no ethylenically unsaturated groups and no cyclic ether groups, liquid crystal compounds having two or more ethylenically unsaturated groups and no cyclic ether groups, and liquid crystal compounds having two or more cyclic ether groups and no ethylenically unsaturated groups. The other liquid crystal compound is more preferably at least one selected from the group consisting of liquid crystal compounds having no ethylenically unsaturated groups and no cyclic ether groups, liquid crystal compounds having two ethylenically unsaturated groups and no cyclic ether groups, and liquid crystal compounds having two cyclic ether groups and no ethylenically unsaturated groups. The other liquid crystal compound is even more preferably at least one selected from the group consisting of liquid crystal compounds having no ethylenically unsaturated groups and no cyclic ether groups, and liquid crystal compounds having two ethylenically unsaturated groups and no cyclic ether groups.

Other rod-shaped liquid crystal compounds are described, for example, in "Makromol. Chem., Vol. 190, p. 2255 (1989)" and "Advanced Materials 5, p. 107 (1993) ", U.S. Pat. No. 4,683,327, U.S. Pat. No. 5,622,648, U.S. Pat. No. 5,770,107, WO 95/22586, WO 95/24455, WO 97/00600, WO 98/23580, WO 98/52905, JP-A-1-272551, JP-A-6-16616, JP-A-7-110469, JP-A-11-80081 and JP-A-2001-328973 may be selected from the compounds described therein. Preferred rod-shaped liquid crystal compounds among the other liquid crystal compounds may be selected from compounds described in, for example, JP-T-11-513019 and JP-A-2007-279688.

Preferred discotic liquid crystal compounds among other liquid crystal compounds may be selected from the compounds described in, for example, JP-A-2007-108732 or JP-A-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 specific examples below.

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 amount of solids in the liquid crystal composition is preferably 70% by mass or less, more preferably 50% by mass or less, even more preferably 30% by mass or less, and particularly preferably 20% by mass or less. 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 contain a specific liquid compound and other liquid crystal compounds.

The ratio of the total amount of liquid crystal compounds to the total amount of solids in 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. Furthermore, the ratio of the total amount of liquid crystal compounds to the total amount of solids in the liquid crystal composition is preferably 60% by mass to 99% by mass, and more preferably 80% by mass to 98% by mass.

(Component of liquid crystal composition: chiral compound)
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 compound (that is, an optically active compound).

The type of chiral compound may be determined, for example, according to the type of liquid crystal compound and the desired helical structure (for example, the twisting method and pitch of the helix). Examples of chiral compounds include known compounds (for example, compounds described in Liquid Crystal Device Handbook, Chapter 3, Section 4-3, Chiral Compounds for TN (twisted nematic) and STN (super-twisted nematic), p. 199, edited by Committee 142 of the Japan Society for the Promotion of Science, 1989), isosorbide derivatives, and isomannide derivatives.

Chiral compounds generally contain an asymmetric carbon atom. However, axially asymmetric compounds and planarly asymmetric compounds that do not contain an asymmetric carbon atom can also be used as chiral compounds. Preferred examples of axially asymmetric compounds and planarly asymmetric compounds include binaphthyl compounds, helicene compounds, and paracyclophane compounds.

From the viewpoint of improving thermal durability, the liquid crystal composition may contain a chiral compound having a polymerizable group. From the viewpoint of improving reactivity and thermal 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 compound 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 compound is the same as the preferred embodiment of the cyclic ether group in the specific liquid crystal compound described above.

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

From the viewpoint of improving moldability, the chiral compound having a polymerizable group preferably includes a chiral compound having one ethylenically unsaturated group and no cyclic ether group, a chiral compound having one cyclic ether group and no ethylenically unsaturated group, or a chiral compound having one ethylenically unsaturated group and one cyclic ether group. Furthermore, the chiral compound having a polymerizable group preferably includes a chiral compound having one ethylenically unsaturated group and no cyclic ether group.

The chiral compound may be a liquid crystal compound.

The liquid crystal composition may contain a photosensitive chiral compound. The photosensitive chiral compound is sensitive to light and can change the helical pitch in the cholesteric liquid crystal phase. The photosensitive chiral compound changes its structure by, for example, absorbing light. The photosensitive chiral compound is preferably a compound that causes at least one reaction selected from the group consisting of a photoisomerization reaction, a photodimerization reaction, and a photodecomposition reaction. A compound that causes a photoisomerization reaction refers to a compound that causes stereoisomerization or structural isomerization by the action of light. Examples of compounds that cause a photoisomerization reaction include azobenzene compounds and spiropyran compounds. A compound that causes a photodimerization reaction refers to a compound that undergoes an addition reaction between two groups and is cyclized by irradiation with light. Examples of compounds that cause a photodimerization reaction include cinnamic acid derivatives, coumarin derivatives, chalcone derivatives, and benzophenone derivatives. Examples of light include ultraviolet light, visible light, and infrared light.

Preferred photosensitive chiral compounds include, for example, chiral compounds represented by the following formula (CH1). The chiral compounds represented by the following formula (CH1) can change the helical pitch in the cholesteric liquid crystal phase depending on the amount of light when irradiated with light.

In formula (CH1), Ar ^{1 CH1} and Ar ^{2 CH2} each independently represent an aryl group or a heteroaromatic ring group, and R ^{1 CH1} and R ^{2 CH2} each independently represent a hydrogen atom or a cyano group.

In formula (CH1), Ar ^CH1 and Ar ^CH2 are each preferably independently an aryl group. The total number of carbon atoms in the aryl group is preferably 6 to 40, more preferably 6 to 30. The aryl group may have a substituent. The substituent is preferably a halogen atom, an alkyl group, an alkenyl group, an alkynyl group, an alkoxy group, a hydroxy group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an acyloxy group, a carboxy group, a cyano group, or a heterocyclic group, and more preferably a halogen atom, an alkyl group, an alkenyl group, an alkoxy group, a hydroxy group, an acyloxy group, an alkoxycarbonyl group, or an aryloxycarbonyl group. ^{Ar CH1} and Ar ^CH2 are each preferably independently an aryl group represented by the following formula (CH2) or formula (CH3).

In formula (CH2) and formula (CH3), R ^CH3 and R ^CH4 each independently represent a hydrogen atom, a halogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a heterocyclic group, an alkoxy group, a hydroxy group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an acyloxy group, a carboxy group, or a cyano group; L ^CH1 and L ^CH2 each independently represent a halogen atom, an alkyl group, an alkoxy group, or a hydroxy group; nCH1 represents an integer of 0 to 4; nCH2 represents an integer of 0 to 6; and * represents the bonding position with respect to the ethylenically unsaturated bond in formula (CH1).

R ^CH3 and R ^CH4 in formula (CH2) and formula (CH3) are each independently preferably a hydrogen atom, a halogen atom, an alkyl group, an alkenyl group, an aryl group, an alkoxy group, a hydroxy group, an alkoxycarbonyl group, an aryloxycarbonyl group, or an acyloxy group, more preferably an alkoxy group, a hydroxy group, or an acyloxy group, and further preferably an alkoxy group.

It is preferable that L ^CH1 and L ^CH2 in formula (CH2) and formula (CH3) are each independently an alkoxy group having 1 to 10 carbon atoms or a hydroxy group.

In formula (CH2), nCH1 is preferably 0 or 1.

In formula (CH3), nCH2 is preferably 0 or 1.

The total number of carbon atoms in the heteroaromatic ring group in Ar ^CH1 and Ar ^CH2 of formula (CH1) is preferably 4 to 40, more preferably 4 to 30. The heteroaromatic ring group may have a substituent. The substituent is preferably a halogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, an alkoxy group, a hydroxy group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an acyloxy group, or a cyano group, more preferably a halogen atom, an alkyl group, an alkenyl group, an aryl group, an alkoxy group, or an acyloxy group. The heteroaromatic ring group is preferably a pyridyl group, a pyrimidinyl group, a furyl group, or a benzofuranyl group, more preferably a pyridyl group or a pyrimidinyl group.

In formula (CH1), R 3 ^CH1 and R ^{3 CH2} are each preferably independently a hydrogen atom.

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

The content of the chiral compound may be determined, for example, according to 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 the chiral compound to the total amount of solids in the liquid crystal composition is preferably 1% by mass to 20% by mass, more preferably 2% by mass to 15% by mass, and even more preferably 3% by mass to 10% by mass.

The helical pitch in the cholesteric liquid crystal phase and the selective reflection wavelength of the cholesteric liquid crystal layer can be easily adjusted not only by the type of liquid crystal compound but also by the content of the chiral compound. For example, if the content of the chiral compound in the liquid crystal composition is doubled, the helical pitch will be halved and the central value of the selective reflection wavelength may also be halved.

The liquid crystal composition preferably contains a polymerization initiator. The polymerization initiator promotes the curing reaction of the liquid crystal composition.

When the liquid crystal composition is cured by exposure to light, it is preferable that the liquid crystal composition contains a photopolymerization initiator. Examples of photopolymerization initiators include photoradical polymerization initiators and photocationic polymerization initiators.

Examples of photopolymerization initiators include α-carbonyl compounds (e.g., U.S. Pat. Nos. 2,367,661 and 2,367,670), acyloin ether compounds (e.g., U.S. 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. Nos. 3,046,127 and 2,951,758), combinations of triaryl imidazole dimers and p-aminophenyl ketones (e.g., U.S. Pat. No. 3,549,367), oxadiazole compounds (e.g., U.S. Pat. No. 4,212,970), acridine compounds, and phenazine compounds (e.g., JP-A-60-105667 and U.S. Pat. No. 4,239,850).

Preferred photoradical polymerization 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 photoradical polymerization initiator or a photocationic polymerization initiator.

From the viewpoint of improving thermal durability, a 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 polymerization initiators.

The content of the polymerization initiator may be determined, for example, according to the structure of the specific liquid crystal compound and the desired helical pitch. From the viewpoints of ease of forming a 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 the polymerization initiator to the total amount of solids in the liquid crystal composition is preferably 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% by mass to 2% by mass, and particularly preferably 0.2% by mass to 1% by mass.

From the viewpoint of improving the strength and durability of the cured cholesteric liquid crystal layer, the liquid crystal composition may contain a crosslinking agent. Preferred crosslinking agents include 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 isocyanate)
(5) Polyoxazoline compounds having an oxazoline group on the side chain. (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 the strength and durability of the cholesteric liquid crystal layer, the ratio of the total amount of the crosslinking agent to the total amount of solids in the liquid crystal composition is preferably 1% by mass to 20% by mass, and more preferably 3% by mass to 15% by mass.

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 improve productivity in addition to improving the strength and durability of the cholesteric liquid crystal layer.

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 the two or more polymerizable groups contained in the polyfunctional polymerizable compound are the same.

Examples of polyfunctional polymerizable compounds include liquid crystal compounds having two or more ethylenically unsaturated groups and no cyclic ether groups, liquid crystal compounds having two or more ethylenically unsaturated groups and two or more cyclic ether groups, liquid crystal compounds having two or more ethylenically unsaturated groups and two or more cyclic ether groups, chiral compounds having two or more polymerizable groups, and crosslinkers having two or more polymerizable groups. The polyfunctional polymerizable compound preferably includes at least one selected from the group consisting of liquid crystal compounds having two or more ethylenically unsaturated groups and no cyclic ether groups, liquid crystal compounds having two or more cyclic ether groups and no ethylenically unsaturated groups, and chiral compounds having two or more polymerizable groups, and more preferably includes a chiral compound having 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 the orientation structure after polymerization, the ratio of the total amount of the polyfunctional polymerizable compound to the total amount of the solid content of the liquid crystal composition is preferably 0.5% by mass to 50% by mass, more 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. When the ratio of the total amount of the polyfunctional polymerizable compound to the total amount of the solid content of the liquid crystal composition is small, the crosslink density of the cholesteric liquid crystal layer is reduced. 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 the solid content of the liquid crystal composition is large, the orientation structure of the cholesteric liquid crystal layer is more likely to be maintained after polymerization. From the viewpoint of improving moldability, it is preferable that the content of the compound having two or more ethylenically unsaturated groups, the compound having two or more cyclic ether groups, and the compound having one or more ethylenically unsaturated groups and one or more cyclic ether groups is regulated among the polyfunctional polymerizable compounds. That is, the ratio of "the total amount of 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 cyclic ether groups" to the total amount of solids in the liquid crystal composition is preferably 0.5% by mass to 50% by mass, more 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.

The liquid crystal composition may contain other additives as necessary. Examples of the other additives include surfactants, polymerization inhibitors, antioxidants, horizontal alignment agents, UV absorbers, light stabilizers, colorants, and metal oxide particles. The liquid crystal composition may contain one or more other additives.

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

The liquid crystal composition may contain one or more solvents.

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

The ratio of the total amount of solids in 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% by mass to 80% by mass, and even more preferably 10% by mass to 80% by mass.

When the liquid crystal composition is cured during the formation of the cholesteric liquid crystal layer, the ratio of the total amount of the solvent to the total amount of solids in the liquid crystal composition when the liquid crystal composition is cured is preferably 5% by mass or less, more preferably 3% by mass or less, even more preferably 2% by mass or less, and particularly preferably 1% by mass or less.

The ratio of the total amount of the 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 particularly preferably 1% by mass or less.

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

The liquid crystal composition is cured, for example, by exposure. The exposure is performed, for example, by irradiating the liquid crystal composition with light. A preferred light source is, for example, a light source capable of irradiating at least one type of light 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 dose is preferably 5 mJ/cm ² to 2,000 mJ/cm ² , and more preferably 10 mJ/cm ² to 1,000 mJ/cm ^2. As an exposure method, for example, the method described in paragraphs 0035 to 0051 of JP-A-2006-23696 may be applied.

In order to facilitate the alignment of the liquid crystal compounds, it is preferable to expose the liquid crystal composition while heating it. The heating temperature is determined, for example, according to the composition of the liquid crystal composition. The heating temperature is, for example, 60°C to 120°C. Examples of heating means include a heater, an oven, a hot plate, an infrared lamp, and an infrared laser.

The liquid crystal composition may be cured, 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 already described.

The liquid crystal composition may be dried by a known method before curing. The liquid crystal composition may be dried by leaving it or air drying. The liquid crystal composition may be dried by heating.

(Middle class)
The decorative sheet for molding according to an embodiment of the present disclosure includes an intermediate layer in contact with a cholesteric liquid crystal layer, the intermediate layer suppressing migration of a low molecular weight compound contained in the cholesteric liquid crystal layer to an adhesive layer through the intermediate layer under a thermal environment, and improving thermal durability.

The intermediate layer contains a polymer (i.e., a specific polymer) having an SP value of 23.0 MPa ^1/2 or more. From the viewpoint of improving heat durability, the SP value of the specific polymer is preferably 23.0 MPa ^1/2 or more, more preferably 23.2 MPa ^1/2 or more, and even more preferably 23.5 MPa ^1/2 or more. For the purpose of improving heat durability, the upper limit of the SP value of the specific polymer is not limited. The upper limit of the SP value of the specific polymer may be 28.0 MPa ^1/2 or 26.0 MPa ^1/2 .

In this disclosure, the SP value is calculated by the Hoy method described in the "Polymer Handbook fourth edition" based on the molecular structure of the target compound. When the target compound is a polymer containing multiple types of structural units, the SP value is represented by the sum of the values obtained by multiplying the SP value of each structural unit by the molar ratio of the structural unit. In a polymer containing multiple types of structural units, the sum of the molar ratios of each structural unit is 1.0. For example, the SP value of a polymer containing structural units X1 and X2 (wherein the sum of the molar ratio of structural unit X1 and the molar ratio of structural unit X2 is 1.0) is represented by the sum of the value obtained by multiplying the SP value of structural unit X1 by the molar ratio of structural unit X1 and the value obtained by multiplying the SP value of structural unit X2 by the molar ratio of structural unit X2. The molecular structure of the target compound (including the molar ratio of the constituent units) is analyzed by pyrolysis gas chromatography/mass spectrometry (i.e., pyrolysis GC/MS) and nuclear magnetic resonance (NMR) using samples collected from the intermediate layer.

The type of the specific polymer is not limited as long as the SP value is 23.0 MPa ^1/2 or more. Examples of the specific polymer include polyvinyl alcohol and modified polyvinyl alcohol. From the viewpoint of storage stability, the specific polymer preferably contains at least one selected from the group consisting of polyvinyl alcohol and modified polyvinyl alcohol, and more preferably contains modified polyvinyl alcohol.

From the viewpoint of adhesion between the intermediate layer and the cholesteric liquid crystal layer, the specific polymer preferably contains a modified polyvinyl alcohol having at least one selected from the group consisting of an ethylenically unsaturated group and a cyclic ether group, and more preferably contains a modified polyvinyl alcohol having an ethylenically unsaturated group. Examples of the ethylenically unsaturated group 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 an acryloyloxy group or a methacryloyloxy group, and more preferably a methacryloyloxy group. Examples of the cyclic ether group 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. The type of polymerizable group in the specific polymer is preferably the same as the type of polymerizable group in the specific liquid crystal compound of the cholesteric liquid crystal layer. Furthermore, the polymerizable group in the chiral compound is preferably the same as the polymerizable group in the specific liquid crystal compound of the cholesteric liquid crystal layer.

From the viewpoint of solubility and adhesion between the intermediate layer and the cholesteric liquid crystal layer, it is preferable that the specific polymer contains a modified polyvinyl alcohol represented by the following formula (I).

In formula (I), L ¹¹ represents a linking group containing an amide bond, an ether bond, a urethane bond, or an ester bond; R ¹¹ represents an alkylene group or an alkyleneoxy group; L ¹² represents a single bond or a linking group; Q ¹¹ represents an ethylenically unsaturated group or a cyclic ether group; on the premise that x1+y1+z1=100 mol%, x1 represents 10 mol% to 99.9 mol%, y1 represents 0.01 mol% to 80 mol%, z1 represents 0 mol% to 70 mol%, k is 0 or 1, and h is 0 or 1.

The linking group represented by L ¹¹ in formula (I) preferably has 1 to 8 carbon atoms, more preferably 2 to 6 carbon atoms, and even more preferably 2 to 4 carbon atoms.

The linking group represented by L ¹¹ in formula (I) may contain other atomic groups in addition to an amide bond, an ether bond, a urethane bond, or an ester bond. Examples of other atomic groups include alkylene groups. The alkylene group may be a linear or branched alkylene group. The number of carbon atoms in the alkylene group is preferably 1 to 8. Examples of linking groups containing an amide bond and an alkylene group include -(CH ₂ ) _n -CO-NH-. n in "-(CH ₂ ) _n -CO-NH-" represents an integer of 1 to 8. n is preferably 1 to 6, more preferably 1 to 4, even more preferably 1 or 2, and particularly preferably 1.

In formula (I), L ¹¹ is preferably a linking group containing an amide bond, more preferably a linking group containing an amide bond and an alkylene group, further preferably —(CH ₂ ) _n —CO—NH—, and particularly preferably —CH ₂ —CO—NH—.

The alkylene group represented by R ¹¹ in formula (I) may be a linear or branched alkylene group. The alkylene group is preferably a linear alkylene group. The number of carbon atoms in the alkylene group is preferably 1 to 6, more preferably 2 to 4, and even more preferably 2. Examples of the alkylene group include -CH ₂ -, -C ₂ H ₄ -, -C ₃ H ₆ -, and -C ₄ H ₈ -.

The alkyleneoxy group represented by R ¹¹ in formula (I) may be a linear or branched alkyleneoxy group. The number of carbon atoms in the alkyleneoxy group is preferably 1 to 6, more preferably 2 to 4, and even more preferably 2. Examples of the alkyleneoxy group include -CH ₂ -O-, -C ₂ H ₄ -O-, -C ₃ H ₆ -O-, and -C ₄ H ₈ -O-.

The number of carbon atoms in the linking group represented by ^L12 in formula (I) is preferably 1 to 8, more preferably 1 to 4, and further preferably 1 or 2. Examples of the linking group include -CO-NH-, -O-, -NH-CO-O-, -CO-O-, an alkylene group, and an alkyleneoxy group.

Examples of the ethylenically unsaturated group represented by ^Q11 in formula (I) 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 an acryloyloxy group or a methacryloyloxy group.

Examples of the cyclic ether group represented by ^Q11 in formula (I) 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 thermal durability, x1 in formula (I) is preferably 40 mol% to 95 mol%, more preferably 60 mol% to 95 mol%, and even more preferably 80 mol% to 95 mol%.

From the viewpoint of achieving both adhesion and moldability, y1 in formula (I) is preferably 0.5 mol% to 25 mol%, more preferably 0.5 mol% to 20 mol%, and even more preferably 0.5 mol% to 15 mol%.

From the viewpoint of solubility in a solvent, z1 in formula (I) is preferably 0.1 mol% to 50 mol%, more preferably 1 mol% to 30 mol%, and even more preferably 3 mol% to 20 mol%.

In formula (I), k is preferably 1.

In formula (I), h is preferably 0.

The intermediate layer may contain one or more specific polymers.

From the viewpoint of thermal durability, the degree of polymerization of the specific polymer is preferably 100 to 1500, more preferably 100 to 1000, and even more preferably 100 to 700. When the degree of polymerization is 100 or more, the thermal durability is improved. When the degree of polymerization is 1500 or less, the viscosity decreases and air bubbles are less likely to remain during the film formation process, resulting in improved thermal durability.

The ratio of the total amount of the specific polymer to the total amount of solids in the intermediate layer is 60% by mass or more. When the above ratio is 60% by mass or more, the low molecular weight compound contained in the cholesteric liquid crystal layer is further suppressed from migrating to the adhesive layer through the intermediate layer in a thermal environment, and the thermal durability is improved. The above ratio is preferably 70% by mass or more, more preferably 80% by mass or more, and even more preferably 85% by mass or more. For the purpose of improving the thermal durability, the upper limit of the above ratio is not limited. The above ratio may be 100% by mass or less. The above ratio may be 95% by mass or less.

The intermediate layer may further contain other components as necessary, such as a polymer other than the specific polymer (e.g., a polymer having an SP value of less than 23.0 MPa ^1/2 ), a polymerization initiator, a solvent, a crosslinking agent (e.g., glutaraldehyde), a catalyst for the crosslinking agent (e.g., a citrate ester), and the like.

From the viewpoints of heat durability, wet heat durability, and adhesion, the thickness of the intermediate layer is preferably 0.1 μm to 10 μm, more preferably 0.3 μm to 7 μm, and even more preferably 0.5 μm to 3 μm.

As long as the desired intermediate layer can be obtained, the method for producing the intermediate layer is not limited. The intermediate layer is formed, for example, using a composition for forming an intermediate layer. The composition for forming an intermediate layer is produced, for example, by mixing a specific polymer with other components as necessary. The mixing method may be selected from known mixing methods. The composition for forming an intermediate layer may be dried by a known method. The composition for forming an intermediate layer may be dried by leaving it or air drying. The composition for forming an intermediate layer may be dried by heating.

(Adhesive layer)
The decorative sheet for molding according to an embodiment of the present disclosure includes an adhesive layer in contact with the intermediate layer. Examples of components of the adhesive layer include an adhesive and an adhesive.

Examples of adhesives include acrylic adhesives, rubber adhesives, and silicone adhesives. Examples of adhesives include the acrylic adhesives, ultraviolet (UV) curing adhesives, and silicone adhesives described in Chapter 2 of "Evaluation of Properties of Release Paper, Release Film, and Adhesive Tape and Technology for Controlling Them," Information Agency, 2004. Note that an acrylic adhesive refers to an adhesive that contains a polymer of a (meth)acrylic monomer ((meth)acrylic polymer). When the adhesive layer contains an adhesive, the adhesive layer may further contain a tackifier.

Examples of adhesives include urethane resin adhesives, polyester adhesives, acrylic resin adhesives, ethylene vinyl acetate resin adhesives, polyvinyl alcohol adhesives, polyamide adhesives, and silicone adhesives. From the viewpoint of higher adhesive strength, urethane resin adhesives and silicone adhesives are preferred.

There are no limitations on the method for producing the adhesive layer as long as the desired adhesive layer can be obtained. The adhesive layer is formed, for example, using a composition containing at least one selected from the group consisting of adhesives and adhesives. The adhesive layer may be formed, for example, using a sheet-shaped adhesive or adhesive. An example of a commercially available sheet-shaped adhesive is molding substrate-less double-sided tape G25 (Nichiei Shinka Co., Ltd.).

In order to achieve both adhesive strength and ease of handling, it is preferable that the thickness of the adhesive layer is 5 μm to 100 μm.

(Substrate)
The decorative sheet for molding according to an embodiment of the present disclosure may include a substrate as necessary. The substrate may be a substrate having releasability. The substrate is preferably a resin substrate, and more preferably a resin film.

Examples of components of the substrate include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), acrylic resin, polyurethane, urethane-acrylic resin, polycarbonate (PC), acrylic-polycarbonate resin, triacetyl cellulose (TAC), cycloolefin polymer (COP), and acrylonitrile/butadiene/styrene copolymer resin (ABS resin). From the viewpoint of moldability and strength, the substrate preferably contains at least one selected from the group consisting of polyethylene terephthalate, acrylic resin, polyurethane, urethane-acrylic resin, polycarbonate, acrylic-polycarbonate resin, and polypropylene resin, and more preferably contains at least one selected from the group consisting of acrylic resin, polycarbonate, and acrylic-polycarbonate resin.

From the viewpoint of improving moldability, the substrate is preferably a substrate having high extensibility. The breaking elongation of the substrate measured in an environment of 80°C is preferably 10% or more, more preferably 15% or more, and even more preferably 20% or more. For the purpose of moldability, the upper limit of the breaking elongation is not limited. From the viewpoint of controlling the thickness of the decorative sheet before and after molding, the breaking elongation of the substrate measured in an environment of 80°C may be 300% or less or 200% or less. Examples of substrates having high extensibility include polycarbonate (PC) and polymethyl methacrylate (PMMA). The breaking elongation of the substrate is measured by a method similar to the method for measuring the breaking elongation of the decorative sheet for molding described above.

The substrate may be a laminated resin substrate having two or more layers. For example, a preferred example of the laminated resin substrate is an acrylic resin/polycarbonate laminate film.

The substrate 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; halogen-based and phosphorus-based organic flame retardants; organic or inorganic fillers such as metal powder, talc, calcium carbonate, potassium titanate, glass fiber, carbon fiber, and wood powder; additives such as antioxidants, ultraviolet inhibitors, lubricants, dispersants, coupling agents, foaming agents, and colorants; and engineering plastics other than the above-mentioned resins, such as polyolefins, polyesters, polyacetals, polyamides, and polyphenylene ethers.

The substrate may be a commercially available product. Examples of commercially available products include the Technoloy (registered trademark) series (acrylic resin film or acrylic resin/polycarbonate resin laminated film, manufactured by Sumitomo Chemical Co., Ltd.), ABS film (manufactured by Okamoto Corporation), ABS sheet (manufactured by Sekisui Seikei Kogyo Co., Ltd.), Teflex (registered trademark) series (PET film, manufactured by Teijin Film Solutions Co., Ltd.), Lumirror (registered trademark) easy-form type (PET film, manufactured by Toray Industries, Inc.), and Pure Thermo (polypropylene film, manufactured by Idemitsu Unitech Co., Ltd.). Examples of commercially available products include Cosmoshine (manufactured by Toyobo Co., Ltd.). Examples of commercially available substrates having high extensibility include A-PET film (manufactured by Mineron Chemical Industry Co., Ltd.).

The thickness of the substrate is determined, for example, according to the application of the molded product to be produced and the handleability of the sheet. The thickness of the substrate is preferably 1 μm or more, more preferably 10 μm or more, even more preferably 20 μm or more, and particularly preferably 50 μm or more. The thickness of the substrate is preferably 500 μm or less, more preferably 450 μm or less, and even more preferably 200 μm or less.

(Other layers)
The molded decorative sheet according to an embodiment of the present disclosure may include other layers as necessary. The other layers may be selected from layers contained in known decorative materials, for example. Examples of the other layers include an orientation layer, a colored layer, a protective layer, a resin layer, an ultraviolet absorbing layer, a reflective layer, a self-repairing layer, an antistatic layer, an antifouling layer, an electromagnetic wave-proof layer, and a conductive layer. Preferred aspects of the orientation layer, the colored layer, the protective layer, the resin layer, and the ultraviolet absorbing layer are described, for example, in International Publication No. WO 2020/122232. The contents of the above documents are incorporated herein by reference.

(Layout of each layer)
As long as the cholesteric liquid crystal layer, the intermediate layer in contact with the cholesteric liquid crystal layer, and the adhesive layer in contact with the intermediate layer are arranged in this order, the arrangement of each layer of the moldable decorative sheet is not limited. The layers of the moldable decorative sheet may be arranged as follows. "/" indicates the boundary between layers.
(1) cholesteric liquid crystal layer/intermediate layer/adhesive layer (2) substrate/cholesteric liquid crystal layer/intermediate layer/adhesive layer (3) cholesteric liquid crystal layer/intermediate layer/adhesive layer/substrate (4) substrate/cholesteric liquid crystal layer/intermediate layer/adhesive layer/substrate (5) colored layer/cholesteric liquid crystal layer/intermediate layer/adhesive layer (6) adhesive layer/intermediate layer/cholesteric liquid crystal layer/intermediate layer/adhesive layer (7) cholesteric liquid crystal layer/intermediate layer/adhesive layer/intermediate layer/cholesteric liquid crystal layer/substrate

(Method of manufacturing decorative sheet for molding)
As long as the desired moldable decorative sheet can be obtained, the manufacturing method of the moldable decorative sheet is not limited. The manufacturing method of the moldable decorative sheet according to one embodiment of the present disclosure preferably includes applying a composition containing a liquid crystal composition (i.e., a liquid crystal composition) onto a substrate, curing the liquid crystal composition applied onto the substrate to form a cholesteric liquid crystal layer, forming an intermediate layer on the cholesteric liquid crystal layer, and forming an adhesive layer on the intermediate layer.

The liquid crystal composition is described in the "Cholesteric Liquid Crystal Layer" section above. The preferred liquid crystal composition is the same as the preferred liquid crystal composition described in the "Cholesteric Liquid Crystal Layer" section above.

Examples of substrates include those described in the "Substrate" section above.

Examples of the method for applying the liquid crystal composition include roll coating, gravure printing, and spin coating. Examples of the method for applying the liquid crystal composition include wire bar coating, extrusion coating, direct gravure coating, reverse gravure coating, and die coating. The liquid crystal composition may be ejected from a nozzle using an inkjet device.

The liquid crystal composition applied onto the substrate may be dried by a known method before curing. The liquid crystal composition is dried, for example, by the method described in the "Cholesteric Liquid Crystal Layer" section above.

There are no limitations on the method for curing the liquid crystal composition applied onto the substrate. The liquid crystal composition can be cured, for example, by the method described in the "Cholesteric Liquid Crystal Layer" section above.

The intermediate layer is formed, for example, by the method described in the above "Intermediate layer" section. In the present disclosure, it is preferable to form an intermediate layer on the cholesteric liquid crystal layer by laminating the cholesteric liquid crystal layer and the intermediate layer. In laminating the cholesteric liquid crystal layer and the intermediate layer, it is preferable to use a laminate including a substrate and an intermediate layer. The laminate including the substrate and the intermediate layer is manufactured, for example, by applying a composition for forming an intermediate layer onto the substrate. The cholesteric liquid crystal layer and the intermediate layer may be laminated using a known laminator. The cholesteric liquid crystal layer and the intermediate layer may be laminated under heating conditions.

The adhesive layer is formed, for example, by the method described in the "Adhesive Layer" section above. In the present disclosure, it is preferable to form an adhesive layer on the intermediate layer by laminating the intermediate layer and the adhesive layer. The intermediate layer and the adhesive layer may be laminated using a known laminator. The intermediate layer and the adhesive layer may be laminated under heating conditions.

(Applications of molding decorative sheets)
The moldable decorative sheet according to an embodiment of the present disclosure can decorate an object through molding. Examples of the object include automobiles (e.g., the interior and exterior of an automobile), electronic devices (e.g., the housing of an electronic device), and packaging containers. The moldable decorative sheet according to an embodiment of the present disclosure may be molded when decorating the object. The moldable decorative sheet according to an embodiment of the present disclosure may be molded before decorating the object. A preferred molding method is described in the "Molded Object" section below.

<Molded products>
A molded product according to an embodiment of the present disclosure is a molded product obtained by molding the moldable decorative sheet according to an embodiment of the present disclosure.

The form of the moldable decorative sheet is described in the above section "Moldable decorative sheet". The preferred form of the moldable decorative sheet is the same as the preferred form of the moldable decorative sheet described in the above section "Moldable decorative sheet".

The molding method of the moldable decorative sheet is not limited. The moldable decorative sheet may be molded by a known method. Preferred molding methods include, for example, three-dimensional molding and insert molding.

Examples of three-dimensional molding include thermoforming, vacuum molding, pressure molding, and vacuum pressure molding. Vacuum refers to a state in which the chamber is evacuated to a vacuum level of 100 Pa or less.

The temperature during three-dimensional molding is preferably 60°C or higher, more preferably 80°C or higher, and even more preferably 100°C or higher. The upper limit of the temperature during three-dimensional molding is preferably 200°C.

The vacuum molding is preferably performed, for example, under a heated vacuum. The vacuum molding is performed, for example, using a vacuum molding technique that is widely known in the molding field. The vacuum molding may be performed, for example, using a Formech 508FS manufactured by Nippon Duki Kogyo Co., Ltd.

In insert molding, a molded product is obtained, for example, by placing a mold decorative sheet in a mold in advance and then injection molding a base resin into the mold. Insert molding produces a molded product in which a mold decorative sheet is integrated with the surface of a resin molded product. A preferred embodiment of insert molding is described, for example, in WO 2020/122232. The contents of the above documents are incorporated herein by reference.

Applications of the molded article according to one embodiment of the present disclosure include, for example, automobiles (e.g., the interior and exterior of automobiles), electronic devices (e.g., housings for electronic devices), and packaging containers. However, the applications of the molded article according to one embodiment of the present disclosure are not limited to the specific examples described above.

<Molded products>
An electronic device according to an embodiment of the present disclosure includes a molded article according to an embodiment of the present disclosure. The aspects of the molded article are described in the above "Molded Article" section. The arrangement and shape of the molded article in the electronic device may be determined according to the purpose. The molded article may be included in the housing of the electronic device. Examples of the electronic device include a smartphone, a mobile phone, and a tablet.

The present disclosure will be described in detail below with reference to examples, but the present disclosure is not limited to these. In the following description, unless otherwise specified, "%" means "% by mass" and "parts" means "parts by mass."

<Ingredients>
(Liquid Crystal Compound 1)
Liquid crystal compound 1 is represented by the following chemical formula.

(Liquid Crystal Compound 2)
The liquid crystal compound 2 is represented by the following chemical formula.

(Liquid Crystal Compound 3)
The liquid crystal compound 3 is represented by the following chemical formula.

(Chiral Compound 1)
Chiral compound 1 is represented by the following chemical formula:

(Chiral Compound 2)
Chiral compound 2 is represented by the following chemical formula:

(Surfactant 1)
Surfactant 1 is represented by the following chemical formula:

(Surfactant 2)
Surfactant 2 is represented by the following chemical formula:

(Modified polyvinyl alcohol 1)
Modified polyvinyl alcohol 1 is represented by the following chemical formula. The unit of the number written to the lower right of each constitutional unit represents mol%. The SP value of modified polyvinyl alcohol 1 is 24.0 MPa ^1/2 . Modified polyvinyl alcohol 1 is a specific polymer in the present disclosure. The polymerization degree of modified polyvinyl alcohol 2 is 400.

(Modified polyvinyl alcohol 2)
Modified polyvinyl alcohol 2 is represented by the following chemical formula. The unit of the number written to the lower right of each constitutional unit represents mol%. The SP value of modified polyvinyl alcohol 2 is 24.0 MPa ^1/2 . Modified polyvinyl alcohol 2 is a specific polymer in the present disclosure and is included in the modified polyvinyl alcohol represented by formula (I). The polymerization degree of modified polyvinyl alcohol 2 is 280.

(Modified polyvinyl alcohol 3)
Modified polyvinyl alcohol 3 is represented by the following chemical formula. The unit of the number written to the lower right of each constitutional unit represents mol%. The SP value of modified polyvinyl alcohol 2 is 24.1 MPa ^1/2 . Modified polyvinyl alcohol 3 is a specific polymer in the present disclosure and is included in the modified polyvinyl alcohol represented by formula (I). The polymerization degree of modified polyvinyl alcohol 3 is 350.

(Modified Polyvinyl Alcohol 4)
Modified polyvinyl alcohol 4 is represented by the following chemical formula. The unit of the number written to the lower right of each constitutional unit represents mol%. The SP value of modified polyvinyl alcohol 4 is 23.8 MPa ^1/2 . Modified polyvinyl alcohol 4 is a specific polymer in the present disclosure and is included in the modified polyvinyl alcohol represented by formula (I). The polymerization degree of modified polyvinyl alcohol 4 is 300.

(Comparative Compound 1)
Comparative compound 1 is represented by the following chemical formula: Comparative compound 1 has an SP value of 22.8 MPa ^1/2 and a weight average molecular weight of 300.

Example 1
A laminate 1A including, in this order, a cholesteric liquid crystal layer-forming substrate, a cholesteric liquid crystal layer 1, an intermediate layer 1, an adhesive layer, and a transparent PET heavy-duty release film was obtained according to the following procedure. "PET" is an abbreviation for polyethylene terephthalate.

(Preparation of substrate for forming cholesteric liquid crystal layer)
Cosmoshine A4160 (thickness: 100 μm, one-sided easy-adhesion treated polyethylene terephthalate film, manufactured by Toyobo Co., Ltd.) was cut to a width of 210 mm and a length of 300 mm to prepare a substrate for forming a cholesteric liquid crystal layer (hereinafter referred to as "substrate" in this paragraph). Next, the surface opposite to the easy-adhesion treated surface of the substrate was subjected to a rubbing treatment (rayon cloth, pressure: 0.1 kgf, rotation speed: 1,000 rpm (revolutions per minute, the same applies below), conveying speed: 10 m/min, number of times: 1 time) in a direction rotated 3° counterclockwise based on the short side direction of the substrate.

(Preparation of Liquid Crystal Composition)
A liquid crystal composition 1 having the following composition was prepared. The ratio of the total amount of the polyfunctional polymerizable compound to the total amount of the solid content of the liquid crystal composition 1 was 17.6 mass %. The "polyfunctional polymerizable compound" in this paragraph specifically means the liquid crystal compound 3.
Liquid crystal compound 1: 10.59 parts by mass Liquid crystal compound 2: 10.59 parts by mass Liquid crystal compound 3: 5.29 parts by mass Chiral compound 1: 2.65 parts by mass Photopolymerization initiator (2,4-diethyl-9H-thioxanthen-9-one): 0.79 parts by mass Surfactant 1: 0.08 parts by mass Surfactant 2: 0.01 parts by mass Organic solvent 1 (methyl ethyl ketone): 63.00 parts by mass Organic solvent 2 (cyclohexanone): 7.00 parts by mass

(Formation of Cholesteric Liquid Crystal Layer)
Liquid crystal composition 1 was applied to the rubbed surface of the cholesteric liquid crystal layer forming substrate using a wire bar (number #7), and then dried for 2 minutes at 80° C. to obtain a laminate including the cholesteric liquid crystal layer forming substrate and a liquid crystal layer. Next, the laminate was placed on a hot plate at 60° C., and the liquid crystal layer of the laminate was irradiated with light at an exposure dose of 300 mJ/cm ² using a metal halide lamp (MAL625NAL manufactured by GS Yuasa Corporation) in a low-oxygen atmosphere (oxygen concentration: 1,000 ppm or less), to harden the liquid crystal layer, thereby forming a cholesteric liquid crystal layer 1.

(Preparation of substrate for forming intermediate layer)
Technoloy C000 (thickness: 100 μm, polycarbonate film, manufactured by Sumika Acrylic Sales Co., Ltd.) was cut to a width of 210 mm and a length of 300 mm to prepare a substrate for forming an intermediate layer.

(Preparation of composition for forming intermediate layer)
An intermediate layer forming composition 1 having the following composition was prepared.
Modified polyvinyl alcohol 1: 3.00 parts by weight Water (solvent): 67.90 parts by weight Methanol (solvent): 29.10 parts by weight

(Formation of intermediate layer)
The intermediate layer forming composition 1 was applied to the intermediate layer forming substrate using a wire bar (number #14), and then dried at 100 ° C for 2 minutes to obtain a laminate including the intermediate layer forming substrate and the intermediate layer 1. Corona treatment was performed on each of the surfaces of the cholesteric liquid crystal layer 1 and the intermediate layer 1 using a tabletop corona treatment device (TEC-8XA, manufactured by Kasuga Electric Co., Ltd., set output: 70 W, operation speed: 1 m / min, number of times: 5 reciprocations). With the cholesteric liquid crystal layer 1 and the intermediate layer 1 facing each other, the cholesteric liquid crystal layer 1 and the intermediate layer 1 were bonded together using a laminator (PROTEUS A3 manufactured by FELLOWES Co., Ltd.) heated to 80 ° C. The obtained laminate includes the cholesteric liquid crystal layer forming substrate, the cholesteric liquid crystal layer 1, the intermediate layer 1, and the intermediate layer forming substrate in this order.

(Formation of adhesive layer)
G25 (acrylic adhesive, adhesive layer thickness: 25 μm, layer structure: transparent PET light release film/adhesive layer/transparent PET heavy release film) manufactured by Nikkei Shinka Co., Ltd. was cut to a width of 210 mm and a length of 300 mm to prepare an adhesive sheet. The intermediate layer forming substrate was peeled off from the intermediate layer 1. The transparent PET light release film was peeled off from the adhesive sheet. With the intermediate layer and the adhesive layer facing each other, the intermediate layer 1 and the adhesive layer were bonded together using a laminator (PROTEUS A3 manufactured by FELLOWES Co., Ltd.) at room temperature. The obtained laminate 1A includes, in this order, the cholesteric liquid crystal layer forming substrate, the cholesteric liquid crystal layer 1, the intermediate layer 1, the adhesive layer, and the transparent PET heavy release film.

Example 2
A laminate 2A including, in this order, a cholesteric liquid crystal layer-forming substrate, a cholesteric liquid crystal layer 1, an intermediate layer 2, an adhesive layer, and a transparent PET heavy-duty release film was obtained according to the same procedure as in Example 1, except that the intermediate layer-forming composition 1 was changed to the intermediate layer-forming composition 2. The composition of the intermediate layer-forming composition 2 is shown below.
Modified polyvinyl alcohol 2: 2.63 parts by weight; Citric acid ester (AS3, manufactured by Sankyo Chemical Co., Ltd.): 0.05 parts by weight; Glutaraldehyde: 0.13 parts by weight; Photopolymerization initiator (Omnirad 2959, manufactured by IGM Resins B.V.): 0.20 parts by weight; Water (solvent): 67.90 parts by weight; Methanol (solvent): 29.10 parts by weight

Example 3
A laminate 3A including, in this order, a cholesteric liquid crystal layer-forming substrate, a cholesteric liquid crystal layer 1, an intermediate layer 3, an adhesive layer, and a transparent PET heavy-duty release film was obtained according to the same procedure as in Example 2, except that intermediate layer-forming composition 2 was changed to intermediate layer-forming composition 3. The composition for intermediate layer-forming composition 3 has the same composition as intermediate layer-forming composition 2, except that modified polyvinyl alcohol 2 was changed to modified polyvinyl alcohol 3.

Example 4
A laminate 4A including, in this order, a cholesteric liquid crystal layer-forming substrate, a cholesteric liquid crystal layer 1, an intermediate layer 4, an adhesive layer, and a transparent PET heavy-duty release film was obtained according to the same procedure as in Example 2, except that the intermediate layer-forming composition 2 was changed to the intermediate layer-forming composition 4. The composition for forming an intermediate layer 4 has the same composition as the intermediate layer-forming composition 2, except that the modified polyvinyl alcohol 2 was changed to the modified polyvinyl alcohol 4.

Example 5
A liquid crystal composition 2 having the following composition was prepared. The ratio of the total amount of the polyfunctional polymerizable compound to the total amount of the solid content of the liquid crystal composition 2 was 35.3 mass %. The "polyfunctional polymerizable compound" in this paragraph specifically means the liquid crystal compound 3.
Liquid crystal compound 1: 7.94 parts by mass Liquid crystal compound 2: 7.94 parts by mass Liquid crystal compound 3: 10.58 parts by mass Chiral compound 1: 2.65 parts by mass Photopolymerization initiator (2,4-diethyl-9H-thioxanthen-9-one): 0.79 parts by mass Surfactant 1: 0.08 parts by mass Surfactant 2: 0.01 parts by mass Organic solvent 1 (methyl ethyl ketone): 63.00 parts by mass Organic solvent 2 (cyclohexanone): 7.00 parts by mass

Except for changing liquid crystal composition 1 to liquid crystal composition 2, the same procedure as in Example 4 was followed to obtain a laminate 5A including, in this order, a substrate for forming a cholesteric liquid crystal layer, a cholesteric liquid crystal layer 2, an intermediate layer 4, an adhesive layer, and a transparent PET heavy-duty release film.

Example 6
According to the method described in the section "Preparation of substrate for forming cholesteric liquid crystal layer" of Example 1, a substrate for forming a cholesteric liquid crystal layer (i.e., Cosmoshine A4160. Hereinafter, referred to as "substrate" in this paragraph) that was rubbed was prepared. According to the description of Example 4, a composition for forming an intermediate layer 4 was prepared. The composition for forming an intermediate layer 4 was applied to the rubbed surface of the substrate using a wire bar (number #14), and dried at 100°C for 2 minutes to form an intermediate layer 4A. The surface of the intermediate layer 4A was subjected to rubbing treatment (rayon cloth, pressure: 0.1 kgf, rotation speed: 1,000 rpm, conveying speed: 10 m/min, number of times: 1 time) in a direction rotated 3° counterclockwise based on the short side direction of the substrate. By the above procedure, a laminate including the substrate and the intermediate layer 4A was obtained.

A laminate including, in this order, a substrate for forming a cholesteric liquid crystal layer, an intermediate layer 4A, a cholesteric liquid crystal layer 1, an intermediate layer 4, an adhesive layer, and a transparent PET heavy-duty release film was obtained according to the same procedure as in Example 4, except that the substrate for forming a cholesteric liquid crystal layer was changed to the laminate already described.

The substrate for forming the cholesteric liquid crystal layer was peeled off from the intermediate layer 4A. The transparent PET light release film was peeled off from a separately prepared G25 manufactured by Nikkei Shinka Co., Ltd. to expose the surface of the adhesive layer. With the intermediate layer 4A and the adhesive layer facing each other, they were bonded together using a room temperature laminator (PROTEUS A3 manufactured by FELLOWES). The obtained laminate 6A contains, in this order, the transparent PET heavy release film, the adhesive layer, the intermediate layer 4A, the cholesteric liquid crystal layer 1, the intermediate layer 4, the adhesive layer, and the transparent PET heavy release film.

Example 7
Except for changing the wire bar (size #14) used to apply the composition for forming an intermediate layer to a wire bar (size #7), the same procedure as in Example 4 was followed to obtain a laminate 7A including, in this order, a substrate for forming a cholesteric liquid crystal layer, a cholesteric liquid crystal layer 1, an intermediate layer 4, an adhesive layer, and a transparent PET heavy-duty release film.

Example 8
A liquid crystal composition 3 having the following composition was prepared. The ratio of the total amount of the polyfunctional polymerizable compound to the total amount of the solid content of the liquid crystal composition 3 was 18.1% by mass. The "polyfunctional polymerizable compound" in this paragraph specifically means the liquid crystal compound 3 and the chiral compound 2.
Liquid crystal compound 1: 10.87 parts by mass Liquid crystal compound 2: 10.87 parts by mass Liquid crystal compound 3: 5.44 parts by mass Chiral compound 2: 1.90 parts by mass Photopolymerization initiator (2,4-diethyl-9H-thioxanthen-9-one): 0.82 parts by mass Surfactant 1: 0.08 parts by mass Surfactant 2: 0.01 parts by mass Organic solvent 1 (methyl ethyl ketone): 63.00 parts by mass Organic solvent 2 (cyclohexanone): 7.00 parts by mass

A laminate was obtained that included, in this order, a substrate for forming a cholesteric liquid crystal layer, a cholesteric liquid crystal layer 3, an intermediate layer 4, an adhesive layer, and a transparent PET heavy-duty release film, following the same procedure as in Example 4, except that liquid crystal composition 1 was changed to liquid crystal composition 3.

Furthermore, a laminate including, in this order, an intermediate layer 4A, a cholesteric liquid crystal layer 1, an intermediate layer 4, an adhesive layer, and a transparent PET heavy-duty release film was obtained by following the same procedure as in Example 6, except for omitting the step of bonding the intermediate layer 4A and the adhesive layer.

The transparent PET peelable film of the laminate containing, in this order, a substrate for forming a cholesteric liquid crystal layer, a cholesteric liquid crystal layer 3, an intermediate layer 4, an adhesive layer, and a transparent PET peelable film was peeled off to expose the surface of the adhesive layer. With the intermediate layer 4A and the exposed adhesive layer facing each other, the intermediate layer 4A and the adhesive layer were bonded together using a room temperature laminator (PROTEUS A3 manufactured by FELLOWES). The resulting laminate 8A contains, in this order, a substrate for forming a cholesteric liquid crystal layer, a cholesteric liquid crystal layer 3, an intermediate layer 4, an adhesive layer, an intermediate layer 4A, a cholesteric liquid crystal layer 1, an intermediate layer 4, an adhesive layer, and a transparent PET peelable film.

<Comparative Example 1>
A laminate 1B including, in this order, a cholesteric liquid crystal layer-forming substrate, a cholesteric liquid crystal layer 1, an intermediate layer 5, an adhesive layer, and a transparent PET heavy-duty release film was obtained according to the same procedure as in Example 1, except that the intermediate layer-forming composition 1 was changed to the intermediate layer-forming composition 5. The composition of the intermediate layer-forming composition 5 is shown below.
Comparative compound 1: 2.79 parts by mass Photopolymerization initiator (Omnirad 2959, manufactured by IGM Resins B.V.): 0.21 parts by mass Acetone (solvent): 97.00 parts by mass

<Comparative Example 2>
A laminate 2B was obtained by following the same procedure as in Example 1, except that no intermediate layer was provided and an adhesive layer was brought into contact with the cholesteric liquid crystal layer 1, a substrate for forming a cholesteric liquid crystal layer, a cholesteric liquid crystal layer 1, an adhesive layer, and a transparent PET heavy-duty release film, in that order.

<Comparative Example 3>
A liquid crystal composition 4 having the following composition was prepared. The composition of the liquid crystal composition 4 is shown below. The ratio of the total amount of the polyfunctional polymerizable compound to the total amount of the solid content of the liquid crystal composition 4 is 52.9 mass %. In this paragraph, the "polyfunctional polymerizable compound" specifically means the liquid crystal compound 3.
Liquid crystal compound 1: 5.29 parts by mass Liquid crystal compound 2: 5.29 parts by mass Liquid crystal compound 3: 15.88 parts by mass Chiral compound 1: 2.65 parts by mass Photopolymerization initiator (2,4-diethyl-9H-thioxanthen-9-one): 0.79 parts by mass Surfactant 1: 0.08 parts by mass Surfactant 2: 0.01 parts by mass Organic solvent 1 (methyl ethyl ketone): 63.00 parts by mass Organic solvent 2 (cyclohexanone): 7.00 parts by mass

Except for changing liquid crystal composition 1 to liquid crystal composition 4, the same procedure as in Comparative Example 2 was followed to obtain laminate 3B including, in this order, a substrate for forming a cholesteric liquid crystal layer, a cholesteric liquid crystal layer 4, an adhesive layer, and a transparent PET heavy-duty release film.

<Comparative Example 4>
Except for changing liquid crystal composition 1 to liquid crystal composition 4, the same procedure as in Example 4 was followed to obtain a laminate 4B including, in this order, a substrate for forming a cholesteric liquid crystal layer, a cholesteric liquid crystal layer 4, an intermediate layer 4, an adhesive layer, and a transparent PET heavy-duty release film.

<Comparative Example 5>
According to the description of Example 1, a cholesteric liquid crystal layer 1 was formed on a substrate for forming a cholesteric liquid crystal layer (hereinafter referred to as "substrate" in this paragraph). According to the description of Example 1, an adhesive sheet was prepared, and a transparent PET light release film was peeled off from the adhesive sheet. With the substrate and the adhesive layer facing each other, the substrate and the adhesive layer were bonded together using a laminator (PROTEUS A3 manufactured by FELLOWES) at room temperature. The obtained laminate 5B includes a transparent PET heavy release film, an adhesive layer, a substrate, and a cholesteric liquid crystal layer 1 in this order.

<Comparative Example 6>
A laminate 6B including, in this order, a cholesteric liquid crystal layer-forming substrate, a cholesteric liquid crystal layer 1, an intermediate layer 6, an adhesive layer, and a transparent PET heavy-duty release film was obtained according to the same procedure as in Example 4, except that the intermediate layer-forming composition 4 was changed to the intermediate layer-forming composition 6. The composition for forming an intermediate layer 6 has the same composition as that for forming an intermediate layer 4, except that 1.58 parts by mass of the 2.63 parts by mass of the modified polyvinyl alcohol 4 was replaced with the comparative compound 1.

<Measurement of Intermediate Layer Thickness>
Using a roller cutter, a sample piece of width 5 mm x length 2 mm was cut out from the laminate. The sample piece was embedded in epoxy resin and cut in the thickness direction of the laminate using a microtome (product name "RM2265", manufactured by Leica). The thickness of the intermediate layer was measured by observing an SEM image of the cross section using a scanning electron microscope (model "S-5500", manufactured by Hitachi High-Technologies Corporation, observation magnification: 10,000 times, acceleration voltage: 2.0 kV). The measurement results are shown in Tables 1 and 2. For laminates including multiple intermediate layers, the thickness of the intermediate layer shown in Tables 1 and 2 indicates the thickness of each intermediate layer unless otherwise specified.

<Evaluation>
The laminates obtained in the examples and comparative examples (that is, laminates 1A to 8A and 1B to 6B) were used to carry out the following evaluations.

(Reflection band center wavelength)
The transmission spectrum of the laminate was measured using an ultraviolet-visible-near infrared spectrophotometer UV-3100PC (manufactured by Shimadzu Corporation). The intensity of the obtained transmittance spectrum was inverted and treated as the reflection spectrum of the laminate. Using the reflection spectrum, the maximum and maximum value of the reflectance was determined as R _max (%), and the average value of two wavelengths showing the half-value reflectance R ^1/2 (%) expressed by the following formula was determined as the central wavelength of the reflection band. The measurement results are shown in Tables 1 and 2.
Formula: R ^1/2 = R _max ÷2

(Heat durability)
After peeling off the transparent PET heavy-duty release film from the laminate, the exposed adhesive layer and a PET film (thickness: 100 μm, Cosmoshine A4360, manufactured by Toyobo Co., Ltd.) were bonded together. For the laminate obtained in Example 6, after peeling off two transparent PET heavy-duty release films from the laminate, each of the two exposed adhesive layers was bonded to a PET film. The transmission spectrum of the obtained laminate was measured using a UV-3100PC ultraviolet-visible near-infrared spectrophotometer (manufactured by Shimadzu Corporation). Next, the laminate was left to stand in an oven at 80° C. for 500 hours. SH-221 manufactured by Espec Corporation was used as the oven. After 500 hours, the transmission spectrum of the laminate was measured according to the method described above. The intensity of the obtained transmittance spectrum was inverted and treated as the reflection spectrum of the laminate. Using the reflection spectrum, the maximum value of the reflectance was determined as R _max (%), and the average value of two wavelengths showing the half-value reflectance R ^1/2 (%) expressed by the following formula was determined as the central wavelength of the reflection band.
Formula: R ^1/2 = R _max ÷2

The absolute value of the difference between the reflection band central wavelength λ1 calculated based on the transmission spectrum of the laminate before heating and the reflection band central wavelength λ2 calculated based on the transmission spectrum of the laminate after heating was determined. The heat durability was evaluated according to the following criteria based on the absolute value of the difference between λ1 and λ2 (|λ1-λ2|), i.e., the degree of change in the reflection band central wavelength. The evaluation results are shown in Tables 1 and 2. A and B are pass levels.
・A: |λ1-λ2|≦5nm
・B: 5nm<|λ1-λ2|≦15nm
・C: 15nm<|λ1-λ2|

(Heat and humidity durability)
The moist heat durability was evaluated according to the method and criteria described in the above section "Heat durability", except that the method of heating the laminate in an oven at 80°C was changed to a method of heating the laminate in a moist heat oven at 60°C and 90% RH. SH-221 manufactured by Espec Corporation was used as the moist heat oven. The evaluation results are shown in Tables 1 and 2.

(Moldability)
After peeling the transparent PET heavy-release film from the laminate, the exposed adhesive layer and A-PET film (thickness: 200 μm, manufactured by Mineron Chemical Industry Co., Ltd.) were bonded together. For the laminate obtained in Example 6, after peeling two transparent PET heavy-release films from the laminate, each of the two exposed adhesive layers was bonded together with an A-PET film. Furthermore, the substrate for forming a cholesteric liquid crystal layer of the laminate (excluding the laminate obtained in Example 6 and Comparative Example 5) was peeled off. The laminate was cut into a size of 10 mm x 50 mm, and a tensile test was performed at a speed of 1,000 mm/sec in an atmosphere of 80°C using a thermo-tensilon (RTF-1310 manufactured by A&D Co., Ltd. and a thermostatic tester TKC). The maximum value at which the sample could be stretched without breaking was measured, and the obtained value was adopted as the breaking elongation. The moldability was evaluated according to the following criteria. The evaluation results are shown in Tables 1 and 2. A and B are pass levels.
A: 20%≦breaking elongation B: 10%≦breaking elongation<20%
C: Breaking elongation < 10%

(Adhesion)
After peeling off the transparent PET heavy-release film of the laminate (excluding the laminate obtained in Example 6), the exposed adhesive layer was attached to glass. For the laminate obtained in Example 6, the transparent PET heavy-release film close to the intermediate layer 4A based on the cholesteric liquid crystal layer was peeled off, and the exposed adhesive layer was attached to glass. Furthermore, after peeling off the transparent PET heavy-release film close to the intermediate layer 4 based on the cholesteric liquid crystal layer, a PET film (thickness: 38 μm, Cosmoshine A4360, manufactured by Toyobo Co., Ltd.) was attached to the exposed adhesive layer. Next, the substrate for forming the cholesteric liquid crystal layer of the laminate (excluding the laminate obtained in Example 6 and Comparative Example 5) was peeled off. A cross-cut test was performed according to the method specified in "JIS K 5600", and the adhesion of the laminate to the glass was evaluated according to the following criteria. The evaluation results are shown in Tables 1 and 2.
A: The number of peeled squares was 0 out of 100 squares.
B: The number of peeled squares was 1 to 19 out of 100 squares.
C: The number of peeled squares was 20 or more out of 100 squares.

The following terms in Tables 1 and 2 have the following meanings:
"Substrate": Substrate for forming a cholesteric liquid crystal layer "Liquid crystal layer": Cholesteric liquid crystal layer "Release film": Transparent PET heavy release film "Content of polyfunctional polymerizable compound": Proportion of the total amount of polyfunctional polymerizable compound to the total amount of solid content of the liquid crystal composition "Content of specific polymer": Proportion of the total amount of specific polymer to the total amount of solid content of the intermediate layer "SP value": SP value of specific polymer or comparative compound "y1": y1 (unit: mol%) in modified polyvinyl alcohol represented by formula (I)

Tables 1 and 2 show that Examples 1 to 8 have superior moldability and heat durability compared to Comparative Examples 1 to 6.

Claims (10)

A cholesteric liquid crystal layer;
an intermediate layer in contact with the cholesteric liquid crystal layer;
an adhesive layer in contact with the intermediate layer,
the intermediate layer comprises a polymer having an SP value of 23.0 MPa ^1/2 or more,
The ratio of the total amount of the polymer to the total amount of solids in the intermediate layer is 60 mass% or more,
The breaking elongation measured in an environment of 80°C is 10% or more,
the absolute value of the difference between the reflection band center wavelength measured before a heating test for 500 hours in an environment at 80° C. and the reflection band center wavelength measured after a heating test for 500 hours in an environment at 80° C. is 0 nm to 15 nm;
Decorative sheet for molding. A cholesteric liquid crystal layer;
an intermediate layer in contact with the cholesteric liquid crystal layer;
an adhesive layer in contact with the intermediate layer,
the intermediate layer comprises a polymer having an SP value of 23.0 MPa ^1/2 or more,
The ratio of the total amount of the polymer to the total amount of solids in the intermediate layer is 60 mass% or more,
The breaking elongation measured in an environment of 80°C is 10% or more,
the absolute value of the difference between the reflection band center wavelength measured before a heating test for 500 hours in an environment of 60°C and 90% RH and the reflection band center wavelength measured after a heating test for 500 hours in an environment of 60°C and 90% RH is 0 nm to 15 nm;
Decorative sheet for molding. 3. The moldable decorative sheet according to claim 1, wherein the polymer comprises at least one selected from the group consisting of polyvinyl alcohol and modified polyvinyl alcohol. The moldable decorative sheet according to any one of claims 1 to 3, wherein the polymer comprises a modified polyvinyl alcohol having at least one selected from the group consisting of an ethylenically unsaturated group and a cyclic ether group. The moldable decorative sheet according to any one of claims 1 to 4 , wherein the polymer comprises a modified polyvinyl alcohol represented by the following formula (I):


In formula (I), L ¹¹ represents a linking group containing an amide bond, an ether bond, a urethane bond, or an ester bond; R ¹¹ represents an alkylene group or an alkyleneoxy group; L ¹² represents a single bond or a linking group; Q ¹¹ represents an ethylenically unsaturated group or a cyclic ether group; on the premise that x1+y1+z1=100 mol%, x1 represents 10 mol% to 99.9 mol%, y1 represents 0.01 mol% to 80 mol%, z1 represents 0 mol% to 70 mol%, k is 0 or 1, and h is 0 or 1. The molding decorative sheet according to claim 5 , wherein y1 is 0.5 mol% to 15 mol%. The molding decorative sheet according to any one of claims 1 to 6 , wherein the central wavelength of the reflection band is 350 nm to 1,200 nm. The decorative sheet for molding according to any one of claims 1 to 7, wherein the thickness of the intermediate layer is 0.5 µm to 0.7 µm. A molded product obtained by molding the moldable decorative sheet according to any one of claims 1 to 8. An electronic device comprising the molded article according to claim 9.