JP7380301B2 - Method for manufacturing liquid crystal cured product laminate - Google Patents

Description

The present invention relates to a liquid crystal cured product laminate including a liquid crystal cured product layer. The present invention also relates to a method for manufacturing a liquid crystal cured product laminate including a liquid crystal cured product layer.

BACKGROUND ART Conventionally, a liquid crystal composition containing a liquid crystal compound is cured to obtain a liquid crystal cured product, and this is used as a film having optical anisotropy. For example, a film of a cured liquid crystal product can be obtained by applying a liquid crystal composition to a support base material having an alignment regulating ability and curing the composition in a state in which the liquid crystal compound is oriented. Such a film can exhibit functions such as circularly polarized light separation and a retardation plate, and therefore can be used in various applications such as optical films and decorative materials. Since such films usually have low mechanical strength, they are used in a state where they are laminated on the surface of a base material that provides strength. The properties of the support base material used for curing the liquid crystal composition may not be compatible with the intended use of the final product, and the liquid crystal composition obtained by curing the liquid crystal composition on the surface of the support base material may not be compatible with the intended use of the final product. In many cases, the adhesion of the product to the supporting substrate is insufficient as it is. Therefore, a layer of liquid crystal cured material is transferred to another base material (for example, Patent Document 1).

Japanese Patent Application Publication No. 2019-188740

In Patent Document 1, the liquid crystal cured material layer and the support base material are bonded together via a specific adhesive layer, thereby achieving high adhesion. In the prior art, when a liquid crystal cured material layer is bonded directly to a support substrate without using such an adhesive layer, sufficient adhesion cannot be obtained. Therefore, a laminate in which a liquid crystal cured material layer is directly bonded to a supporting base material and has sufficient adhesion has not been obtained so far. On the other hand, the adhesive layer has a certain thickness and is generally prone to deterioration over time. Therefore, when an adhesive layer is provided, the thickness of the resulting laminate increases undesirably, and the durability of the laminate increases. performance may decrease. Further, a process for providing an adhesive layer is required, which increases costs.

Therefore, an object of the present invention is to provide a liquid crystal cured product laminate having a base material and a liquid crystal cured product layer, which has a simple structure, has high durability, and is thin. .

A further object of the present invention is to provide a liquid crystal cured product laminate having a base material and a liquid crystal cured product layer, which has a simple structure, has high durability, and can easily produce a thin laminate. The purpose is to provide a method.

According to the present invention, the following is provided.

[1] A liquid crystal cured product laminate comprising a base material A and a liquid crystal cured product layer provided directly on the surface of the base material A,
The liquid crystal cured product layer is a layer of a cured product obtained by aligning and polymerizing a polymerizable liquid crystal compound,
A liquid crystal cured material laminate, wherein the adhesiveness of the liquid crystal cured material layer to the substrate A is higher than classification 1 in an adhesion test according to JIS K5600-5-6.
[2] The liquid crystal cured product laminate according to [1], wherein the liquid crystal cured product layer is a layer of a resin having cholesteric regularity.
[3] The material constituting the base material A is a resin containing an alicyclic structure-containing polymer, an acrylic resin, a polyethylene terephthalate resin, a triacetyl cellulose resin, glass, or a combination thereof, [1] or [2] The liquid crystal cured product laminate described in ].
[4] A method for manufacturing a liquid crystal cured product laminate, comprising a base material A and a liquid crystal cured product layer provided directly on the surface of the base material A, comprising:
Step 1: Applying a liquid crystal composition containing a polymerizable liquid crystal compound onto the surface of the base material B to form a layer of the liquid crystal composition,
Step 2: Orienting the polymerizable liquid crystal compound in the layer of the liquid crystal composition,
Step 3: In an atmosphere containing oxygen, the layer of the liquid crystal composition is irradiated with energy rays to cure the layer of the liquid crystal composition to form a cured liquid crystal layer, and the substrate B and the cured liquid crystal layer are cured. and Step 4: Pressing the multilayer and the base material A in a direction in which the surface on the liquid crystal cured material layer side contacts the base material A, in this order. Production method.
[5] The manufacturing method according to [4], further comprising a step 5 of peeling the base material B from the cured liquid crystal layer after the step 4.
[6] The manufacturing method according to [4] or [5], wherein the surface of the multilayer product obtained in step 3 on the liquid crystal cured material layer side has tackiness.
[7] The manufacturing method according to any one of [4] to [6], wherein the energy ray in the step 3 is ultraviolet light, and the irradiation amount is 100 mJ/cm ² or more.
[8] The manufacturing method according to any one of [4] to [7], further comprising a step 6 of additionally irradiating the liquid crystal cured material layer with energy rays after the step 4.

According to the present invention, it is possible to provide a liquid crystal cured product laminate having a base material and a liquid crystal cured product layer, which has a simple configuration, has high durability, and is thin.

According to the present invention, a liquid crystal cured material laminate having a base material and a liquid crystal cured material layer, which has a simple structure, high durability, and a thin thickness, can be easily manufactured. method can be provided. In particular, according to the production method of the present invention, it is possible to easily produce a high-quality liquid crystal cured product laminate in which disordered orientation in the liquid crystal cured product layer is suppressed while utilizing the tackiness of the liquid crystal cured product layer. be able to.

Hereinafter, the present invention will be described in detail by showing embodiments and examples. However, the present invention is not limited to the embodiments and examples shown below, and may be implemented with arbitrary changes within the scope of the claims of the present invention and equivalents thereof.

In the following description, "(meth)acrylic" means "acrylic", "methacrylic", or a mixture thereof. "(thio)epoxy" means "epoxy", "thioepoxy", or mixtures thereof. Moreover, "iso(thio)cyanate" means "isocyanate", "isothiocyanate", or a mixture thereof.

In the following description, the adhesive layer is a layer of adhesive, and unless otherwise specified, adhesive is defined as an adhesive in the narrow sense (after energy ray irradiation or heat treatment, the shear storage modulus at 23°C is It includes not only adhesives having a shear storage modulus of 1 MPa to 500 MPa, but also adhesives having a shear storage modulus of less than 1 MPa at 23°C.

[Overview of liquid crystal cured product laminate]
The liquid crystal cured product laminate of the present invention includes a base material A and a liquid crystal cured product layer provided directly on the surface of the base material A.

[Base material A]
When manufacturing a liquid crystal cured product laminate using the manufacturing method of the present invention, the surface of the base material A does not need to have an alignment regulating force to orient the polymerizable liquid crystal compound, and has high tackiness like an adhesive layer. There's no need. Therefore, the material of the base material A is not limited to those that can provide such surface performance. Therefore, as the material for the base material A, a material that can impart desired physical properties to the liquid crystal cured product laminate as a product can be selected from a wide range of options.

Specific examples of the material for the base material A include resins containing alicyclic structure-containing polymers, acrylic resins, polyethylene terephthalate (PET) resins, triacetyl cellulose (TAC) resins, glass, and combinations thereof. Among these, resins containing alicyclic structure-containing polymers are preferred because they have excellent optical properties and mechanical properties. Specific examples of materials constituting the base material A, such as the alicyclic structure-containing polymer, optional components of the resin, and their ratios, include those described in JP 2019-188740A. In particular, preferred specific examples of resins containing alicyclic structure-containing polymers include cycloolefin polymer-containing resins such as "Zeonor" manufactured by Nippon Zeon; "Arton" manufactured by JSR; and "TOPAS" manufactured by TOPAS ADVANCED POLYMERS. Can be mentioned. Among acrylic resins, polymethyl methacrylate resin is particularly preferred because it has excellent optical properties and mechanical properties.

Substrate A may include an adhesion-enhancing layer provided on its surface. In that case, the surface on the adhesion improving layer side can be the surface on which the liquid crystal cured material layer is provided.
Examples of adhesion-improving layers include various layers known as layers that can be provided on the surface of a base material to improve the adhesive force between the base material and other materials via adhesives, and layers on the surface of the base material. Various known layers can be cited as layers that can improve the adhesive force between the base material and the ink layer by providing the layer.
A more specific example of the adhesion-improving layer is an easy-adhesion layer coated on the surface of the base material. Examples of films provided with an easily adhesive layer that can be used as the substrate A include various commercially available polyethylene terephthalate resin film substrates provided with an easily adhesive layer. Specific examples thereof include Cosmoshine A4100 and A4300 (manufactured by Toyobo), Lumirror U34 (manufactured by Toray Industries), and Diafoil O-100E and T-600E (manufactured by Mitsubishi Gas Chemical). The adhesion-improving layer provided on these films is solid and has no tackiness, so if the surface of the cured liquid crystal layer is completely cured, there will be a gap between the base material A and the cured liquid crystal layer. Although sufficient adhesive strength cannot be obtained, the desired adhesive strength can be obtained by using the manufacturing method of the present invention.

The substrate A may be one in which the surface on the side on which the liquid crystal cured material layer is provided has been subjected to a surface treatment in order to improve adhesion. Specific examples of such surface treatments include corona treatment and saponification treatment. For example, when the base material A is a triacetyl cellulose film, it is particularly preferable to saponify the surface thereof from the viewpoint of improving adhesion.

The thickness of the base material A is not particularly limited, and can be set to a desired thickness depending on the application. When the liquid crystal cured product laminate is used as an optical member, the thickness of the base material A is preferably 1 μm or more, more preferably 10 μm or more, and preferably 1000 μm or less, more preferably 500 μm or less.

[Liquid crystal cured material layer]
The liquid crystal cured product layer is a layer of a cured product obtained by aligning and polymerizing a polymerizable liquid crystal compound. Specifically, the liquid crystal cured material layer can be formed by forming a liquid crystal composition containing a polymerizable liquid crystal compound into a layer, aligning the polymerizable liquid crystal compound in the layer, and polymerizing it.

Preferably, the liquid crystal composition is a cholesteric liquid crystal composition. A cholesteric liquid crystal composition refers to a composition in which the polymerizable liquid crystal compound can exhibit a liquid crystal phase with cholesteric regularity (cholesteric liquid crystal phase) when the polymerizable liquid crystal compound contained in the liquid crystal composition is oriented. . When molecules in a layer of a liquid crystal composition "have cholesteric regularity", it means that molecules in the layer have a specific regularity as described below. When the molecules within a layer have cholesteric regularity, the molecules are arranged within the layer in a multilayered manner. In each molecular layer, the molecules are aligned so that their molecular axes are oriented in a fixed direction. The alignment direction in a second plane that overlaps the first plane is slightly angularly shifted from the alignment direction in a first plane inside the layer of the liquid crystal composition. The orientation direction in the next third plane that further overlaps the second plane is further shifted by a slight angle from the orientation direction in the second plane. In this way, in a plurality of planes arranged in an overlapping manner, the angles of the molecular axes in the planes are sequentially shifted (twisted). A structure in which the direction of the molecular axis is twisted in this way becomes an optically chiral structure.

When a cholesteric liquid crystal composition is used as the liquid crystal composition, when a layer of the liquid crystal composition is formed, the polymerizable liquid crystal compound can exhibit a cholesteric liquid crystal phase in the layer. Therefore, when this liquid crystal composition is cured, the polymerizable liquid crystal compound is polymerized in a state exhibiting a cholesteric liquid crystal phase, so that a cholesteric resin layer, that is, a layer of resin having cholesteric regularity can be obtained as a liquid crystal cured product layer. . The layer of resin having cholesteric regularity has cholesteric regularity and is itself a non-liquid crystal layer.

The cholesteric resin layer usually has a circularly polarized light separating function. That is, it has the property of transmitting one of right-handed circularly polarized light and left-handed circularly polarized light, and reflecting a part or all of the other circularly polarized light. Such reflection in the liquid crystal cured material layer reflects circularly polarized light while maintaining its chirality.

As the polymerizable liquid crystal compound, a photopolymerizable liquid crystal compound is preferable. As the photopolymerizable liquid crystal compound, any compound that can be polymerized by irradiation with energy rays, either by itself or in combination with a polymerization initiator, can be used. Among these, as the photopolymerizable liquid crystal compound suitably used in the cholesteric liquid crystal composition, a rod-like liquid crystal compound having two or more reactive groups in one molecule is preferable, and a compound represented by formula (1) is particularly preferable. .
R ³ -C ³ -D ³ -C ⁵ -MC ⁶ -D ⁴ -C ⁴ -R ⁴ Formula (1)

In formula (1), R ³ and R ⁴ are reactive groups, and each independently represents a (meth)acrylic group, a (thio)epoxy group, an oxetane group, a thietanyl group, an aziridinyl group, a pyrrole group, a vinyl group. , allyl group, fumarate group, cinnamoyl group, oxazoline group, mercapto group, iso(thio)cyanate group, amino group, hydroxyl group, carboxyl group, and alkoxysilyl group. By having these reactive groups, a cured liquid crystal layer with high mechanical strength can be obtained when the liquid crystal composition is cured.

In formula (1), D ³ and D ⁴ each independently represent a single bond, a linear or branched alkyl group having 1 to 20 carbon atoms, and 1 to 20 carbon atoms. represents a group selected from the group consisting of linear or branched alkylene oxide groups.

In formula (1), C ³ to C ⁶ each independently represent a single bond, -O-, -S-, -S-S-, -CO-, -CS-, -OCO-, -CH ₂ -, -OCH ₂ -, -CH=N-N=CH-, -NHCO-, -O-(C=O)-O-, -CH ₂ -(C=O)-O-, and -CH ₂ Represents a group selected from the group consisting of O-(C=O)-.

In formula (1), M represents a mesogenic group. Specifically, M is azomethines, azoxys, phenyls, biphenyls, terphenyls, naphthalenes, anthracenes, benzoic acid esters, cyclohexane carbon, which may be unsubstituted or have a substituent. 2 to 4 that are the same or different from each other selected from the group consisting of acid phenyl esters, cyanophenylcyclohexanes, cyano-substituted phenylpyrimidines, alkoxy-substituted phenylpyrimidines, phenyldioxanes, tolanes, and alkenylcyclohexylbenzonitrile. The skeletons are -O-, -S-, -S-S-, -CO-, -CS-, -OCO-, -CH ₂ -, -OCH ₂ -, -CH=N-N=CH- , -NHCO-, -O-(C=O)-O-, -CH ₂ -(C=O)-O-, and -CH ₂ O-(C=O)-, etc. represents a group.

Examples of the substituent that the mesogenic group M may have include a halogen atom, an alkyl group having 1 to 10 carbon atoms which may have a substituent, a cyano group, a nitro group, -O-R ⁵ , - OC(=O)-R ⁵ , -C(=O)-OR ⁵ , -OC(=O)-OR ⁵ , -NR ⁵ -C(=O)-R ⁵ , -C(=O)-NR ⁵ R ⁷ or -OC(=O)-NR ⁵ R ⁷ is exemplified. Here, R ⁵ and R ⁷ represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms. When R ⁵ and R ⁷ are alkyl groups, the alkyl groups include -O-, -S-, -O-C(=O)-, -C(=O)-O-, -O-C (=O)-O-, -NR ⁶ -C(=O)-, -C(=O)-NR ⁶ -, -NR ⁶ -, or -C(=O)- may be present (However, this excludes cases where two or more of each of -O- and -S- are interposed adjacent to each other.) Here, R ⁶ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.

Examples of the substituents in the "alkyl group having 1 to 10 carbon atoms which may have a substituent" include halogen atoms, hydroxyl groups, carboxyl groups, cyano groups, amino groups, and 1 to 10 carbon atoms. 6 alkoxy groups, alkoxyalkoxy groups having 2 to 8 carbon atoms, alkoxyalkoxyalkoxy groups having 3 to 15 carbon atoms, alkoxycarbonyl groups having 2 to 7 carbon atoms, 2 carbon atoms Examples thereof include an alkylcarbonyloxy group having 2 to 7 carbon atoms, an alkoxycarbonyloxy group having 2 to 7 carbon atoms, and the like.

Moreover, it is preferable that the rod-shaped liquid crystal compound has an asymmetric structure. Here, the asymmetric structure means, in formula (1), R ³ -C ³ -D ³ -C ⁵ -M- and -MC ⁶ -D ⁴ -C ⁴ -R ⁴ with the mesogenic group M as the center. When compared, these are different structures. By using a rod-like liquid crystal compound having an asymmetric structure, alignment uniformity can be further improved.

Preferred specific examples of rod-like liquid crystal compounds include the following compounds (B1) to (B10). Further, these may be used alone or in combination of two or more in any ratio.

When the liquid crystal composition contains the above-described rod-like liquid crystal compound, the liquid crystal composition preferably contains a compound represented by formula (2) as an alignment aid in combination with the rod-like liquid crystal compound.
R ¹ -A ¹ -B-A ² -R ² (2)

In formula (2), R ¹ and R ² are each independently a linear or branched alkyl group having 1 to 20 carbon atoms, or a linear or branched alkyl group having 1 to 20 carbon atoms. or a branched alkylene oxide group, a hydrogen atom, a halogen atom, a hydroxyl group, a carboxyl group, a (meth)acrylic group that may have an optional bonding group, an epoxy group, a mercapto group, an isocyanate group, an amino group, and a cyano group.

The alkyl group and alkylene oxide group may be unsubstituted or substituted with one or more halogen atoms. Furthermore, the halogen atom, hydroxyl group, carboxyl group, (meth)acrylic group, epoxy group, mercapto group, isocyanate group, amino group, and cyano group are an alkyl group having 1 to 2 carbon atoms, and an alkylene oxide group. It may be bonded to a group.

Preferred examples of R ¹ and R ² include a halogen atom, a hydroxyl group, a carboxyl group, a (meth)acrylic group, an epoxy group, a mercapto group, an isocyanate group, an amino group, and a cyano group.

Moreover, it is preferable that at least one of R ¹ and R ² is a reactive group. By having a reactive group as at least one of R ¹ and R ² , the compound represented by formula (2) is fixed in the liquid crystal cured material layer during curing, and a stronger layer can be formed. Examples of the reactive group include a carboxyl group, a (meth)acrylic group, an epoxy group, a mercapto group, an isocyanate group, and an amino group.

In formula (2), A ¹ and A ² each independently represent a 1,4-phenylene group, a 1,4-cyclohexylene group, a cyclohexene-1,4-ylene group, a 4,4'-biphenylene group, or a 4,4-phenylene group. , 4'-bicyclohexylene group, and 2,6-naphthylene group. The 1,4-phenylene group, 1,4-cyclohexylene group, cyclohexene-1,4-ylene group, 4,4'-biphenylene group, 4,4'-bicyclohexylene group, and 2,6-naphthylene group is unsubstituted or substituted with one or more substituents such as halogen atom, hydroxyl group, carboxyl group, cyano group, amino group, alkyl group having 1 to 10 carbon atoms, halogenated alkyl group, etc. You can leave it there. When two or more substituents are present in each of A ¹ and A ² , they may be the same or different.

Particularly preferred as A ¹ and A ² are groups selected from the group consisting of 1,4-phenylene group, 4,4'-biphenylene group, and 2,6-naphthylene group. These aromatic ring skeletons are relatively rigid compared to alicyclic skeletons, and have a high affinity with the mesogen of the rod-shaped liquid crystal compound, resulting in higher alignment uniformity.

In formula (2), B is a single bond, -O-, -S-, -S-S-, -CO-, -CS-, -OCO-, -CH ₂ -, -OCH ₂ -, -CH =N-N=CH-, -NHCO-, -O-(C=O)-O-, -CH ₂ -(C=O)-O-, and -CH ₂ O-(C=O)- selected from the group.
Particularly preferable examples of B include a single bond, -O-(C=O)-, and -CH=N-N=CH-.

Particularly preferred specific examples of the compound represented by formula (2) include the following compounds (A1) to (A10). These may be used alone or in combination of two or more in any ratio.

In the above compound (A3), "*" represents a chiral center.

The weight ratio represented by (total weight of compounds represented by formula (2))/(total weight of rod-like liquid crystal compounds) is preferably 0.001 or more, more preferably 0.01 or more, and still more preferably 0.001 or more. 05 or more, preferably 1 or less, more preferably 0.65 or less. By setting the weight ratio above the lower limit, alignment uniformity can be improved in the layer of the liquid crystal composition. Further, by setting the amount to be equal to or less than the upper limit, alignment uniformity can be increased. Furthermore, the stability of the liquid crystal phase of the liquid crystal composition can be increased. Furthermore, since the refractive index anisotropy Δn of the liquid crystal composition can be increased, it is possible to stably obtain a liquid crystal cured material layer having desired optical performance, such as selective reflection performance for circularly polarized light, for example. Here, the total weight of the compounds represented by formula (2) refers to the weight when only one type of compound represented by formula (2) is used, and the total weight when two or more types are used. Shows total weight. Similarly, the total weight of rod-like liquid crystal compounds refers to the weight when only one type of rod-like liquid crystal compound is used, and the total weight when two or more types are used.

Furthermore, when the compound represented by formula (2) and a rod-like liquid crystal compound are used in combination, it is preferable that the molecular weight of the compound represented by formula (2) is less than 600, and the molecular weight of the rod-like liquid crystal compound is 600 or more. It is preferable that Thereby, the compound represented by formula (2) can enter into the gaps between the rod-like liquid crystal compounds having a larger molecular weight than the compound represented by the formula (2), so that alignment uniformity can be improved.

The liquid crystal composition may include a polymerization initiator. As the polymerization initiator, a compound capable of generating radicals or acids by energy rays such as ultraviolet rays can be used. From the viewpoint of ease of controlling irradiation, etc., a polymerization initiator capable of polymerization by ultraviolet rays is particularly preferred. In the production method of the present invention, radical polymerization initiators are preferred from the viewpoint of utilizing polymerization inhibition by oxygen.

Specific examples of radical polymerization initiators include benzoin, benzyl dimethyl ketal, benzophenone, biacetyl, acetophenone, Michler's ketone, benzyl, benzyl isobutyl ether, tetramethylthiuram mono(di)sulfide, 2,2-azobisisobutyronitrile, 2,2-azobis-2,4-dimethylvaleronitrile, benzoyl peroxide, di-tert-butyl peroxide, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one , 1-(4-isopropylphenyl)-2-hydroxy-2-methylpropan-1-one, thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-diethylthioxanthone, methylbenzoyl formate, 2,2 -diethoxyacetophenone, β-ionone, β-bromostyrene, diazoaminobenzene, α-amylcinnamic aldehyde, p-dimethylaminoacetophenone, p-dimethylaminopropiophenone, 2-chlorobenzophenone, pp'-dichlorobenzophenone, pp'-bisdiethylaminobenzophenone, benzoin ethyl ether, benzoin isopropyl ether, benzoin n-propyl ether, benzoin n-butyl ether, diphenyl sulfide, bis(2,6-methoxybenzoyl)-2,4,4-trimethyl-pentylphosphine oxide, 2,4,6-trimethylbenzoyldiphenyl-phosphine oxide, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, 2-methyl-1[4-(methylthio)phenyl]-2-morpho Linopropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one, anthracenebenzophenone, α-chloroanthraquinone, diphenyl disulfide, hexachlorobutadiene, pentachlorobutadiene , octachlorobutene, 1-chloromethylnaphthalene, and 1,2-octanedione-1-[4-(phenylthio)-2-(o-benzoyloxime)] and 1-[9-ethyl-6-(2- Examples include carbazole oxime compounds such as methylbenzoyl)-9H-carbazol-3-yl]ethanone 1-(o-acetyloxime). On the other hand, specific examples of cationic polymerization initiators include (4-methylphenyl)[4-(2-methylpropyl)phenyl]iodonium hexafluorophosphate, 3-methyl-2-butynyltetramethylenesulfonium hexafluoroantimonate, Examples include diphenyl-(p-phenylthiophenyl)sulfonium hexafluoroantimonate. Further, one type of these may be used alone, or two or more types may be used in combination in any ratio. Furthermore, if necessary, curability may be controlled using a tertiary amine compound as a photosensitizer or polymerization accelerator.

Commercially available products can be used as polymerization initiators. Commercially available products include "N-1414", "N-1717", "N-1919", "PZ-408", "NCI-831", "NCI-930" (manufactured by ADEKA); "Irgacure 369" ", "Irgacure 907," "Irgacure OXE 01," "Irgacure OXE 02," "Irgacure 379 EG" (manufactured by BASF), and the like.

The liquid crystal composition may further include chiral agents, surfactants, and other optional components. Specific examples of these and their content ratios include those exemplified in JP-A No. 2019-188740.

The thickness of the liquid crystal cured material layer is preferably 0.5 μm or more, more preferably 0.7 μm or more, even more preferably 1.0 μm or more, and preferably 10.0 μm or less, more preferably 7.0 μm or less, and even more preferably is 5.0 μm or less. When the thickness of the liquid crystal cured material layer is at least the lower limit of the above range, effective optical properties can be obtained. For example, when the liquid crystal cured material layer is a layer having a circularly polarized light separation function, Can effectively reflect polarized light. Furthermore, by setting the thickness of the liquid crystal cured product layer to be less than or equal to the upper limit of the above range, the transmittance of light in a wavelength band other than the selective reflection band can be increased.

From the viewpoint of using the liquid crystal cured material layer for optical purposes, the liquid crystal cured material layer is preferably a transparent layer without clouding. Specifically, when measuring the haze of the liquid crystal cured material layer, the value is preferably 2% or less, more preferably 1.5% or less, and most preferably 1.0% or less. preferable. If the orientation of the molecules in the cured liquid crystal product is insufficient, haze may increase and the transparency of the appearance may be impaired. By employing the manufacturing method of the present invention as a method for manufacturing a liquid crystal cured product laminate, a liquid crystal cured product laminate having such a low haze liquid crystal cured product layer can be easily produced.

[Adhesion]
In the liquid crystal cured product laminate of the present invention, the liquid crystal cured product layer is provided directly on the surface of the base material A. Directly means that no other layer is interposed between the liquid crystal cured material layer and the base material A, and specifically, the liquid crystal cured material layer and the base material A are bonded between them. layer or structural layer used to form the liquid crystal cured material layer, such as a liquid crystal alignment layer.

In the liquid crystal cured product laminate of the present invention, the adhesion of the liquid crystal cured product layer to the substrate A is higher than Class 1 in the adhesion test according to JIS K5600-5-6. That is, the adhesion between the base material A and the liquid crystal cured material layer of the liquid crystal cured product laminate of the present invention was determined according to JIS K5600-5-6 (1999) "Adhesion (crosscut method)" according to classification 0 to classification 5. When evaluated on a 6-level scale, the results fall under category 0 or category 1. The adhesion is more preferably of a class 0 high. A more specific test method may be as described in the Examples of the present application.

A liquid crystal cured product laminate having a structure in which a liquid crystal cured product layer is directly provided on the surface of the base material A and having such high adhesion has not been obtained so far. The liquid crystal cured product laminate of the present invention has high adhesion due to direct contact between the liquid crystal cured product layer and the base material, so it has a simple structure, high durability, and a thin thickness. It can be a laminate.

[Optional component]
The liquid crystal cured product laminate of the present invention may include arbitrary constituent elements in addition to the base material A and the liquid crystal cured product layer.
For example, the liquid crystal cured material laminate may include an additional layer provided on the surface of the substrate A opposite to the liquid crystal cured material layer. Such an additional layer may be, for example, a layer that supplements the mechanical strength of the liquid crystal cured product laminate together with the base material A, or a layer that adds further optical function to the liquid crystal cured product laminate.
For example, the liquid crystal cured product laminate may include an additional layer provided on the surface of the liquid crystal cured product layer on the side opposite to the base material A. Such an additional layer may be, for example, a layer that protects the cured liquid crystal layer. For this layer, the base material B used in the manufacturing method described below may be used as it is, or another release film provided after the base material B is peeled off.

[Applications of liquid crystal cured product laminate]
The liquid crystal cured product laminate of the present invention can be used as an optical member that utilizes the optical anisotropy of the liquid crystal cured product layer. Specific examples of the optical member include a circularly polarized light separating film, a retardation plate, a decorative material having an optical effect, and the like.

[Method for manufacturing liquid crystal cured product laminate]
The method for producing a liquid crystal cured product laminate of the present invention is a method for producing a liquid crystal cured product laminate comprising a base material A and a liquid crystal cured product layer provided directly on the surface of the base material A, comprising the following steps. Steps 1 to 4 are included in this order.
Step 1: Step of applying a liquid crystal composition containing a polymerizable liquid crystal compound onto the surface of base material B to form a layer of the liquid crystal composition Step 2: Orienting the polymerizable liquid crystal compound in the layer of the liquid crystal composition Step 3: In an atmosphere containing oxygen, the layer of the liquid crystal composition is irradiated with energy rays to cure the layer of the liquid crystal composition to form a cured liquid crystal layer. Step of obtaining a layered product Step 4: Step of crimping the multilayered product and the base material A in the direction in which the surface on the liquid crystal cured material layer side and the base material A are in contact with each other.

The method for producing a liquid crystal cured product laminate of the present invention may include the following Step 5, Step 6, or both of these as optional steps.
Step 5: After Step 4, the step of peeling the base material B from the liquid crystal cured material layer. Step 6: After Step 4, the step of additionally irradiating the liquid crystal cured material layer with energy rays.

According to the method for manufacturing a liquid crystal cured product laminate of the present invention, the liquid crystal cured product layer has a structure in which it is directly provided on the surface of the base material A, and has a high adhesion property (for example, adhesion according to JIS K5600-5-6). A liquid crystal cured product laminate having a classification of 1 or higher in the properties test can be easily obtained.

[Base material B]
As the base material B, a plate-like or film-like base material having properties suitable for carrying out the production method of the present invention can be appropriately selected and used. As the material constituting the base material B, a base material that has alignment regulating power on its surface and has durability against the liquid crystal composition can be appropriately selected. By having the alignment regulating power, it is possible to regulate the alignment direction of the polymerizable liquid crystal compound and obtain a well-aligned liquid crystal cured product layer. Specifically, the durability of a liquid crystal composition refers to the degree to which the liquid crystal composition is eroded by components such as a solvent when the liquid crystal composition is applied to the surface of the liquid crystal composition. means as low as possible. The base material B may consist of a single layer or a plurality of layers.

As the material constituting the base material B, from among the materials exemplified as the materials constituting the base material A, those that can impart an alignment regulating force to the surface and have durability against the liquid crystal composition can be appropriately selected and used. . Specifically, plastic materials such as PET resin and resin containing an alicyclic structure-containing polymer can be used.

The base material B may have an alignment film on its surface. For example, the base material B can be a base material comprising the above-mentioned plastic material and an alignment film provided on its surface.

Prior to step 1, the base material B may be subjected to treatments for imparting alignment regulating force, improving surface wettability, and the like. Specifically, a treatment for imparting an orientation regulating force such as a rubbing treatment or a stretching treatment may be performed.

[Step 1 and Step 2]
As the liquid crystal composition and the polymerizable liquid crystal compound contained therein used in Step 1, those described above can be appropriately employed. In particular, those in which polymerization is inhibited by oxygen are preferably those in which polymerization is achieved by radical polymerization. Specifically, as the polymerizable liquid crystal compound and the optional polymerization initiator, those in which the polymerization reaction proceeds by radical polymerization can be appropriately selected.

Examples of coating methods in step 1 include wire bar coating, dip coating, spray coating, spin coating, roll coating, gravure coating, air knife coating, curtain coating, slide coating, and extrusion coating. An example is the coat method. The thickness of the layer of the liquid crystal composition formed by coating can be adjusted as appropriate so that the thickness of the cured liquid crystal layer in the cured liquid crystal laminate as a product becomes a desired thickness.

If the orientation of the polymerizable liquid crystal compound is achieved immediately after coating, the specific operation in step 2 is not necessary, but if necessary, a step such as heating the layer of the liquid crystal composition may be performed to achieve orientation. May be achieved. For example, when the liquid crystal composition contains a solvent, it is preferable to perform heating in step 2 to volatilize the solvent.

[Step 3]
The energy ray irradiation in step 3 is performed in an atmosphere containing oxygen. By performing the irradiation in an atmosphere containing oxygen, tackiness can be easily imparted to the surface of the resulting cured liquid crystal layer. To explain this point specifically, one surface of the layer of the liquid crystal composition provided on the substrate B is in contact with the substrate B, and the other surface is exposed and in contact with gas in the atmosphere. Here, by using a liquid crystal composition that has a property that polymerization of its components is inhibited by oxygen, and by performing irradiation in an atmosphere containing oxygen, polymerization occurs only on the exposed surface of the layer of the liquid crystal composition. The polymerization reaction can be achieved in an inhibited manner. As a result, in the resulting cured liquid crystal layer, a portion with a low degree of polymerization and tackiness is formed only in a shallow region from the exposed surface, and a portion with a high degree of polymerization and sufficient tackiness is formed in a deeper region. A part with a certain hardness is formed.

The energy rays used in step 3 may be appropriately selected from those suitable for polymerizing the photopolymerizable liquid crystal compound. Specifically, energy rays such as visible rays, ultraviolet rays, and infrared rays may be employed. Ultraviolet light is particularly preferred from the viewpoint of ease of use of a polymerization initiator and ease of controlling irradiation.

In the case of irradiating ultraviolet rays in step 3, the amount of ultraviolet irradiation is preferably 100 mJ/cm ² or more, more preferably 200 mJ/cm ² or more, and most preferably 300 mJ/cm ² or more. By setting the amount of ultraviolet irradiation to the above-mentioned lower limit or more, it is possible to suppress the disorder of molecular orientation in the liquid crystal cured material layer in step 4, and to suppress the occurrence of whitening and hue unevenness of the liquid crystal cured material layer. can. The upper limit of the amount of ultraviolet irradiation can be set within a range that can maintain desired tackiness on the surface of the cured liquid crystal layer. Further, from the viewpoint of productivity, the upper limit of the irradiation amount is preferably 5000 mJ/cm ² or less, more preferably 3500 mJ/cm ² or less.

The oxygen concentration in the atmosphere during the irradiation in step 3 is preferably 1% or more, more preferably 10% or more, from the viewpoint of maintaining the tackiness of the surface of the cured liquid crystal layer. Further, from the viewpoint of easily securing an atmosphere, the oxygen concentration in air, that is, about 21% is particularly preferable. The upper limit is not particularly limited, and may be, for example, 100%.

When carrying out step 3, it is preferable to control the temperature of the liquid crystal composition layer and the liquid crystal cured material layer formed as a result of curing within a desired range. By controlling the temperature in this manner, undesirable progress of polymerization on the surface of the cured liquid crystal layer can be suppressed, and the tackiness of the surface of the cured liquid crystal layer can be maintained. Specifically, since the layer of the liquid crystal composition is usually heated by irradiation with energy rays, it is preferable to cool the layer. It is preferable to maintain the temperature at about 15° C. to 30° C. by cooling. More specifically, a small amount of water at a predetermined temperature is poured on the upper surface of a plate placed horizontally, and a multilayered material including a layer of base material B and a liquid crystal composition is placed on top of the top surface of the board on the side of base material B. Such cooling can be achieved by placing the composite layer in a downward direction, thereby placing the composite through a layer of water. Moreover, as another aspect, such cooling can also be achieved by bringing the multilayer material into close contact with the surface of a roll whose temperature is controlled to a predetermined temperature so that the surface on the base material B side is in contact with the roll surface.

As a result of carrying out step 3, the layer of the liquid crystal composition is cured to become a cured liquid crystal layer, and a multilayer product including the base material B and the cured liquid crystal layer is obtained. Preferably, the surface of the multilayer material on the liquid crystal cured material layer side has tackiness. The presence or absence of tackiness can be determined by pressing a finger against the surface and then releasing it. If the uneven pattern of a fingerprint remains, it can be determined that tackiness is present, and if it does not, it can be determined that tackiness is not present. Evaluation of tackiness can be performed at room temperature of about 24°C.

[Step 4]
In step 4, the base material A is pressure-bonded to the multi-layered product including the base material B and the liquid crystal cured material layer obtained in step 3. The pressure bonding is performed in a direction in which the surface on the liquid crystal cured material layer side and the base material A are in contact with each other. By performing such pressure bonding, it is possible to achieve adhesion of the liquid crystal cured material layer to the base material A by utilizing the tackiness of the liquid crystal cured material layer. On the other hand, in step 3, in the deeper region of the liquid crystal cured material layer than the tacky part, a part with a high degree of polymerization and sufficient hardness is formed, so that the deformation of the liquid crystal cured material layer and the layer Undesirable phenomena such as disordered orientation of molecules within the substrate are suppressed.

Prior to step 4, one or both of the bonding surfaces may be subjected to surface treatment. An example of surface treatment is corona treatment. By performing the surface treatment, the adhesion of the liquid crystal cured material layer to the base material A can be further improved.

The temperature at which Step 4 is performed is not particularly limited, and can be adjusted as appropriate to a temperature that achieves good pressure bonding. When the liquid crystal cured material layer has tackiness, pressure bonding can be performed at a room temperature of about 15°C to 30°C. Moreover, when the tackiness of the liquid crystal cured material layer is insufficient, heating may be performed and pressure bonding may be performed at a high temperature, thereby achieving good adhesion of the liquid crystal cured material layer to the base material A. The heating temperature range can be appropriately adjusted within a temperature range in which significant deterioration of the base material A and the liquid crystal cured material layer does not occur. Specifically, the temperature may preferably be 150°C or lower.

As a result of carrying out step 4, the layer structure is (base material B) / (liquid crystal cured product layer) / (base material A), and the liquid crystal cured product layer is provided directly on the surface of base material A. A laminate is obtained. This may be used as a liquid crystal cured product laminate as it is, or it may be further subjected to an arbitrary process and then used as a liquid crystal cured product laminate.

[Optional process]
As an optional step, after step 4, step 5 of peeling the base material B from the cured liquid crystal layer may be performed. That is, the base material B can be removed from the laminate having the layer structure of (base material B)/(cured liquid crystal layer)/(base material A) obtained in step 4. As a result of this step, a liquid crystal cured product laminate having a layer structure of (liquid crystal cured product layer)/(substrate A) can be obtained.

As another optional step, after step 4, step 6 may be performed in which the liquid crystal cured material layer is additionally irradiated with energy rays. By performing additional irradiation with energy rays after step 4, it is possible to achieve a sufficient degree of polymerization in the liquid crystal cured product laminate as a product while enjoying the adhesion benefits of tackiness in step 4.

If both Step 5 and Step 6 are performed, Step 6 may be performed at any stage after Step 4 is completed. For example, if the adhesion of the liquid crystal cured material layer to the substrate A is weakened by additional irradiation, the peeling operation in step 5 can be easily achieved by performing step 5 before performing step 6. can. For example, if the durability of the cured liquid crystal layer against the peeling operation is insufficient before carrying out step 6, step 6 may be carried out before carrying out step 5 to increase the strength of the cured liquid crystal layer. Accordingly, the durability of the cured liquid crystal product against peeling operations can be increased.

In the case of irradiating ultraviolet rays in step 6, the amount of ultraviolet irradiation is preferably 100 mJ/cm ² or more, more preferably 200 mJ/cm ² or more. By setting the amount of ultraviolet irradiation to the above-mentioned lower limit or more, the durability of the obtained liquid crystal cured product laminate in the usage environment can be improved. For example, when using a liquid crystal cured product laminate, it is possible to suppress deterioration of the liquid crystal cured product layer due to heat and ultraviolet rays, and as a result, it is possible to maintain good optical properties and appearance of the liquid crystal cured product layer for a long period of time. I can do it. From the viewpoint of productivity, the upper limit of the irradiation amount is preferably 1000 mJ/cm ² or less, more preferably 500 mJ/cm ² or less.

The present invention will be specifically described below with reference to Examples. However, the present invention is not limited to the following examples, and may be implemented with arbitrary changes within the scope of the claims of the present invention and equivalents thereof.
In the following description, "%" and "part" expressing amounts are based on weight, unless otherwise specified. Further, the operations described below were performed at normal temperature and normal pressure in the atmosphere unless otherwise specified.

〔Evaluation methods〕
[Exterior observation]
The liquid crystal cured material layer was observed with illumination applied from an oblique direction, and the presence or absence of cloudiness was observed. If no clouding was observed, it was determined that there was no clouding. If cloudiness was observed, its degree was observed. The degree of cloudiness observed in the appearance after transfer in Example 2 was determined to be "slightly cloudy." If the degree of cloudiness was higher than that, and the degree of cloudiness was observed in the appearance after transfer in Example 1, it was determined to be "slightly cloudy." If the degree of cloudiness was higher than that, and the degree of cloudiness was observed in the appearance after transfer in Comparative Example 6, it was determined to be "cloudy". If the degree of cloudiness was higher than that, and the degree of cloudiness was observed in the appearance after transfer in Comparative Example 2, it was determined that there was "severe cloudiness".

[Tackiness]
A finger was pressed against the surface of the cured liquid crystal layer (the exposed surface opposite to the base material side) and then released. If no fingerprint pattern remained, the tackiness was determined to be "none." If an uneven pattern remained, its degree was observed. If the result was comparable to that of Example 1, it was rated as "Yes," and if there was tackiness, but it was clearly lower than the result of Example 1, it was rated as "Slightly." Evaluation of tackiness was performed at about 24°C.

[Adhesion]
Adhesion was evaluated based on JIS K5600-5-6 "Adhesion - Crosscut method".
The liquid crystal cured material layer of the liquid crystal cured material laminate was cut using a cross-cut guide to produce 25 grids (square sections) each side of which was 2 mm. Next, an adhesive tape was strongly pressed onto the parts of the laminate formed in a grid pattern. Next, the end of the adhesive tape is held at 60° to the surface of the liquid crystal cured product laminate (as specified in JIS K5600-5-6, an unbent state is 180°, and a completely folded state is 0°). The adhesive tape was peeled off from the laminate at once by pulling it at an angle of (defined angle), and the condition of the peeled surface was evaluated in the following 6 grades from Class 0 to Class 5. As the adhesive tape, cellophane adhesive tape (manufactured by Nichiban Co., Ltd., trade name "CT405AP-24", width 24 mm) was used.

Category 0: The edges of the cut are completely smooth and there is no peeling at any of the grid points.
Category 1: Small peeling of the paint film at the intersection of cuts. The cross-cut area is clearly affected by no more than 5%.
Category 2: The coating is peeling off along the edges of the cut and/or at the intersections. The cross-cut portion is clearly affected by more than 5%, but not more than 15%.
Category 3: The paint film is partially or completely peeled off along the edges of the cut, and/or various parts of the eye are partially or completely peeled off. The cross-cut area is clearly affected by more than 15%, but never more than 35%.
Category 4: The paint film has partially or completely peeled off along the edge of the cut, and/or some spots have partially or completely peeled off. The cross-cut area is clearly affected by no more than 65%.
Category 5: Any degree of peeling that cannot be classified even in Category 4.

[Example 1]
(1-1. Liquid crystal composition)
The polymerizable liquid crystal compound and other components were mixed in the ratios shown in Table 1, and stirred at a temperature of about 24° C. for 1 hour to obtain a uniform liquid crystal composition.

Compound (B5) was produced according to the method described in International Publication No. WO2009/041512. The compound (A10) used was one produced according to the method described in JP-A-11-100575.

(1-2. Steps 1 and 2)
As the substrate B, a cycloolefin film (trade name "Zeonor ZF16-100", manufactured by Nippon Zeon, thickness 100 μm, same hereinafter) was prepared, and the surface was subjected to a rubbing treatment. The liquid crystal composition obtained in (1-1) was applied onto the rubbed surface using a No. 6 wire bar, and dried at 80° C. for 3 minutes. As a result, a layer of a liquid crystal composition containing a polymerizable liquid crystal compound oriented in a cholesteric liquid crystal phase was formed, and a composite 1 including a base material B and a layer of the liquid crystal composition was obtained.

(1-3. Process 3)
A SUS plate was placed horizontally, and a small amount of water at room temperature (approximately 24° C.) was poured on the top surface. The composite layer 1 was placed thereon so that the surface on the base material B side faced downward. Thereby, the composite layer 1 was placed on the surface of the SUS plate with a layer of water interposed therebetween.

In this state, the layer of the liquid crystal composition was irradiated with ultraviolet rays. Irradiation was performed in air. A metal halide lamp was used as the irradiation light source. Irradiation was performed from above onto the layer of the liquid crystal composition under conditions such that the cumulative illuminance was 100 mJ/cm ² . Thereby, the layer of the liquid crystal composition was cured to form a cured liquid crystal product, and a multilayered product 2 including the base material B and the cured liquid crystal layer was obtained.

In the liquid crystal cured material layer of the obtained composite 2, the polymerizable liquid crystal compound polymerizes while maintaining the cholesteric liquid crystal phase, and as a result, the liquid crystal cured material layer becomes a cholesteric resin layer having a circularly polarized light separating function. was. Upon appearance observation at this point, the cured liquid crystal layer was evaluated to be a transparent layer with no clouding. The surface of the cured liquid crystal layer had tackiness. The thickness of the liquid crystal cured product layer was 1.6 μm.

(1-4. Process 4)
As the base material A, another cycloolefin film was prepared. One surface of the base material A and the surface of the liquid crystal cured material layer side of the multilayer material 2 obtained in (1-3) were each subjected to corona treatment. These were stacked so that their treated surfaces were in contact with each other, and pressed together using a rubber hand roller at room temperature (approximately 24° C.). As a result, a multilayer material 3 having a layer structure of (base material B)/(cured liquid crystal layer)/(substrate A) was obtained.

(1-5. Process 5)
The base material B was peeled off from the composite layer 3. Thereby, a liquid crystal cured product laminate including the liquid crystal cured product layer and the base material A was obtained.
The adhesion between the liquid crystal cured product layer and the substrate A of the obtained liquid crystal cured product laminate was classified as 0. At this point, the appearance of the cured liquid crystal layer was evaluated to be slightly cloudy.

[Examples 2 to 18]
The production of a liquid crystal cured product laminate and each process were carried out in the same manner as in Example 1, except that the integrated illuminance in step (1-3) and the material of the base material A were changed as shown in Tables 2 and 3. We conducted an evaluation. The evaluation results are shown in Tables 2 and 3.

[Comparative example 1]
A multilayer product comprising a liquid crystal cured material layer and base material B was obtained by the same operations as in (1-1) to (1-3) (i.e., steps 1 to 3) of Example 1, except for the following changes. Ta.
- In (1-3), irradiation was performed not in air but in a nitrogen atmosphere.
- In (1-3), the integrated illuminance was changed to 450mJ/ ^cm2 .
The resulting multilayer product was used as a cured liquid crystal laminate without going through steps 4 and 5, and its adhesion and appearance were evaluated. The results are shown in Table 4.

[Comparative example 2]
A multilayered product comprising a liquid crystal cured material layer and base material B was obtained by the same operations as in (1-1) to (1-3) of Example 1, except for the following changes.
- In (1-2), the surface of the base material B was subjected to corona treatment before the rubbing treatment on the surface of the base material B.
- In (1-3), irradiation was performed not in air but in a nitrogen atmosphere.
- In (1-3), the integrated illuminance was changed to 450mJ/ ^cm2 .
The resulting multilayer product was used as a cured liquid crystal laminate without going through steps 4 and 5, and its adhesion and appearance were evaluated. The results are shown in Table 4.

[Comparative example 3]
A multilayered product comprising a liquid crystal cured material layer and base material B was obtained by the same operations as in (1-1) to (1-3) of Example 1, except for the following changes.
- In (1-2), after rubbing the surface of the substrate B and before applying the liquid crystal composition, the surface of the substrate B was subjected to corona treatment.
- In (1-3), irradiation was performed not in air but in a nitrogen atmosphere.
- In (1-3), the integrated illuminance was changed to 450mJ/ ^cm2 .
The resulting multilayer product was used as a cured liquid crystal laminate without going through steps 4 and 5, and its adhesion and appearance were evaluated. The results are shown in Table 4.

[Comparative Examples 4 to 6]
A liquid crystal cured product layer was prepared in the same manner as in Comparative Examples 1 to 3, except that a PET film (trade name "Cosmoshine A4100", manufactured by Toyobo, thickness 100 μm, with an easily adhesive layer on one side) was used as the substrate B. A multi-layered product including the base material B and the base material B was obtained. The surface treatment and the formation of the liquid crystal composition layer were performed on the side of the PET film that did not have the easily adhesive layer.

[Comparative example 7]
In (1-3), a liquid crystal cured product laminate was produced and each step was evaluated in the same manner as in Example 2, except that the irradiation was performed in a nitrogen atmosphere instead of in air. The evaluation results are shown in Table 4.

[Comparative example 8]
In (1-3), an attempt was made to manufacture a liquid crystal cured product laminate and evaluate each step using the same operations as in Example 3, except that the irradiation was performed under a nitrogen atmosphere instead of in air. However, because the liquid crystal cured material layer did not adhere to the substrate A by the pressure bonding in (1-4), it was not possible to obtain a liquid crystal cured material laminate comprising the liquid crystal cured material layer and the substrate A. The evaluation results are shown in Table 4.

COP: Cycloolefin film (trade name "Zeonor ZF16-100", manufactured by Nippon Zeon, thickness 100 μm)
PET: In Examples 6, 11, and 16 of PET film (trade name "Cosmoshine A4100", having an easily adhesive layer on one side), the liquid crystal cured material layer was transferred to the side having the easily adhesive layer. In Comparative Examples 4 to 6, the surface treatment and the formation of the liquid crystal composition layer were performed on the side of the PET film that did not have the easy-adhesion layer.
Acrylic: Acrylic board (product name "Acrylite E", Mitsubishi Rayon, thickness 2mm)
Glass: Glass plate (soda glass), thickness 0.7mm
TAC: TAC film (product name "TACPHAN PLC905GL", manufactured by LOHO, thickness 40 μm)

As is clear from the results of Examples and Comparative Examples, the liquid crystal cured product laminate of the present invention obtained by the method for producing a liquid crystal cured product laminate of the present invention is advantageous in reducing the thickness without using an adhesive layer. Although it has a simple structure, it can be highly durable. Further, it is possible to suppress the occurrence of clouding in the liquid crystal cured material layer during the manufacturing process, and in this respect, it is possible to easily produce a high quality liquid crystal cured material laminate.

Claims (4)

A method for producing a liquid crystal cured product laminate, comprising a base material A and a liquid crystal cured product layer provided directly on the surface of the base material A,
Step 1: Applying a liquid crystal composition containing a polymerizable liquid crystal compound onto the surface of the base material B to form a layer of the liquid crystal composition,
Step 2: Orienting the polymerizable liquid crystal compound in the layer of the liquid crystal composition,
Step 3: In an atmosphere containing oxygen, the layer of the liquid crystal composition is irradiated with ultraviolet rays to cure the layer of the liquid crystal composition to form a cured liquid crystal layer, and the substrate B and the cured liquid crystal layer are cured. and Step 4: Press-bonding the multilayer and the base material A in a direction in which the surface on the liquid crystal cured material layer side and the base material A are in contact with each other, in this order. ,
The step 3 is carried out by controlling the temperature of the layer of the liquid crystal composition and the cured liquid crystal layer formed as a result of curing at 15° C. to 30° C., and the amount of ultraviolet ray irradiation is 400 mJ/cm ² The above is the manufacturing method. The manufacturing method according to claim 1 , further comprising a step 5 of peeling the base material B from the liquid crystal cured material layer after the step 4. The manufacturing method according to claim 1 or 2 , wherein the surface of the multilayered product obtained in the step 3 on the liquid crystal cured material layer side has tackiness. The manufacturing method according to any one of claims 1 to 3 , further comprising a step 6 of additionally irradiating the liquid crystal cured material layer with energy rays after the step 4.