JP7053870B2 - Manufacturing method of laminated body, manufacturing method of optical member - Google Patents

Description

The present invention relates to a method for manufacturing a laminated body and a method for manufacturing an optical member.

The layer in which the cholesteric liquid crystal phase is fixed (hereinafter, also referred to as "cholesteric liquid crystal layer") is a layer having a property of selectively reflecting either right-handed circularly polarized light or left-handed circularly polarized light in a specific wavelength range. It is known and has been developed for various uses.
For example, Patent Document 1 discloses an embodiment in which a liquid crystal compound having a polymerizable group is polymerized on a substrate to obtain a cholesteric liquid crystal layer.

Japanese Unexamined Patent Publication No. 2013-500152

In recent years, thinning of products using a cholesteric liquid crystal layer has been used. Therefore, it is desirable that only the cholesteric liquid crystal layer can be transferred onto the substrate after the cholesteric liquid crystal layer is formed on the support.
When the present inventors examined the transferability of the cholesteric liquid crystal layer disclosed in Patent Document 1, the adhesion to other substrates was inferior and the transferability was inferior.
In addition to the cholesteric liquid crystal layer, there has been a demand for similar improvement in transferability for a retardation layer having a retardation. The retardation layer means a layer other than the cholesteric liquid crystal layer and having a retardation in the in-plane direction or the thickness direction.

In view of the above circumstances, the present invention provides a method for producing a laminate having excellent transferability to another substrate of an optical layer including a functional layer selected from the group consisting of a cholesteric liquid crystal layer and a retardation layer. That is the issue.
Another object of the present invention is to provide a method for manufacturing an optical member.

The present inventors have conducted diligent studies on the above-mentioned problems, and found that the above-mentioned problems can be solved by the following configuration.

(1) Temporary support and
Includes an optical layer, which is adjacently placed on the temporary support.
The optical layer includes a functional layer selected from the group consisting of a cholesteric liquid crystal layer and a retardation layer.
A method for manufacturing a laminated body in which the functional layer is arranged at the position farthest from the temporary support in the optical layer.
A step of forming a precursor layer containing a liquid crystal compound having a polymerizable group directly on the temporary support or via another layer, and
A step of orienting the liquid crystal compound in the precursor layer and then irradiating the precursor layer with light from the surface opposite to the temporary support side of the precursor layer to carry out a curing treatment to obtain a functional layer. Have,
The precursor layer contains a partial structure represented by the formula (1) described later.
The light at the time of light irradiation includes light having a wavelength of 265 nm, and contains light.
A method for producing a laminate, wherein the irradiation amount of light having a wavelength of 265 nm is 5 mJ / cm ² or more.
(2) The precursor layer further contains a surfactant and contains
The method for producing a laminate according to (1), wherein at least one of the liquid crystal compound and the surfactant has a partial structure.
(3) The method for producing a laminate according to (1) or (2), wherein the functional layer is a cholesteric liquid crystal layer.
(4) The precursor layer contains a chiral agent whose spiral-inducing force is changed by light irradiation.
The method for producing a laminate according to (3), wherein the cholesteric liquid crystal layer has a pitch gradient structure in which the spiral pitch changes in the thickness direction.
(5) The method for producing a laminate according to (4), wherein the half width of the integrated reflection spectrum of the cholesteric liquid crystal layer is 80 nm or more.
(6) The section according to any one of (1) to (5), wherein at least a part of the bright part and the dark part derived from the cholesteric liquid crystal phase has a wavy structure in the cross section of the cholesteric liquid crystal layer observed by the scanning electron microscope. Method of manufacturing a laminate of.
(7) The precursor layer is arranged on the temporary support via another layer, and the precursor layer is arranged on the temporary support.
The method for producing a laminate according to any one of (1) to (6), wherein the other layer is a cholesteric liquid crystal layer.
(8) The method for manufacturing a laminate according to (7), wherein the twisting direction of the spiral of the cholesteric liquid crystal layer, which is a functional layer, and the twisting direction of the spiral of the cholesteric liquid crystal layer, which is another layer, are opposite to each other.
(9) The method for producing a laminate according to (7) or (8), wherein the cholesteric liquid crystal layer, which is another layer, has a pitch gradient structure in which the spiral pitch changes in the thickness direction.
(10) The optical layer in the laminate obtained by the production method according to any one of (1) to (9) is brought into contact with the base material directly or via another layer to peel off the temporary support. A method for manufacturing an optical member, which comprises a step of obtaining an optical member including a base material and an optical layer.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a method for producing a laminate having excellent transferability to another substrate of an optical layer including a functional layer selected from the group consisting of a cholesteric liquid crystal layer and a retardation layer.
Further, according to the present invention, it is possible to provide a method for manufacturing an optical member.

It is a schematic diagram for demonstrating process 1-1. It is a schematic diagram for demonstrating the method of light irradiation in a step 2. It is a schematic diagram for demonstrating the laminated body obtained by the step 2. It is a schematic diagram for demonstrating the structure of a cholesteric liquid crystal layer. It is a schematic diagram for demonstrating process 1-2.

Hereinafter, the present invention will be described in detail. In addition, the numerical range represented by using "-" in this specification means the range including the numerical values before and after "-" as the lower limit value and the upper limit value.

In the present invention, the visible light is light having a wavelength visible to the human eye among electromagnetic waves, and is light having a wavelength range of 380 to 780 nm. Ultraviolet rays are light in a wavelength region of 10 nm or more and less than 380 nm.

A feature of the production method of the present invention is that it irradiates light containing light having a wavelength of 265 nm during the curing treatment of the precursor layer containing the partial structure represented by the formula (1) described later. By irradiating the precursor layer with light having a wavelength of 265 nm, the optical Fries rearrangement proceeds with the curing of the precursor layer. Examples of the optical Fries rearrangement include dislocations represented by the following scheme.

Due to the occurrence of optical Fries rearrangement, a partial structure having a phenolic hydroxyl group is formed. Therefore, many partial structures having phenolic hydroxyl groups are generated on the surface of the functional layer on the light irradiation surface side, and as a result, the adhesion to other base materials is improved.

Hereinafter, the production method of the present invention will be described for each embodiment.
The first embodiment of the manufacturing method of the present invention represents an embodiment in which a precursor layer is directly formed on a temporary support, and the second embodiment of the manufacturing method of the present invention comprises another layer on a temporary support. It represents an embodiment of forming a precursor layer through.
In the following, first, the first embodiment will be described in detail.

<< First Embodiment >>
The first embodiment of the manufacturing method of the present invention includes steps 1-1 to 2 described later.
Hereinafter, the procedure of each step will be described in detail.

<Process 1-1>
Step 1-1 is a step of forming a precursor layer containing a liquid crystal compound having a polymerizable group directly on the temporary support. By carrying out this step, a precursor layer, which is a layer to be cured, is formed. More specifically, by carrying out this step, the precursor layer 12 is formed directly on the temporary support 10 as shown in FIG.
In the following, first, the members and materials used in this step will be described in detail.

(Temporary support)
The temporary support is a base material that supports the precursor layer, and is detachably adhered to the optical layer described later. In other words, the temporary support is a detachable support. As will be described later, when the optical layer is transferred, it is separated into a temporary support and an optical layer.

The material constituting the temporary support is not particularly limited, and is, for example, a polyester resin, a cellulose resin, a (meth) acrylic resin, a polycarbonate resin, a styrene resin, a polyolefin resin, a vinyl chloride resin, and an amide. Examples include based resins.
The (meth) acrylic resin is a general term for acrylic resins and methacrylic resins.

The temporary support may have a single-layer structure or a multi-layer structure.
When the temporary support has a multi-layer structure, the temporary support may include a substrate and a base layer containing a resin arranged on the substrate. By providing the base layer (particularly, the base layer that has not been subjected to the rubbing treatment), the wavy structure described later is likely to be formed in the cholesteric liquid crystal layer arranged on the surface of the base layer.
In the above description, the base layer is described as an example of the layer constituting the temporary support, but as will be described later, the base layer may be a part of the optical layer depending on the components constituting the base layer.

The material constituting the substrate is not particularly limited, and examples thereof include the materials constituting the support described above.
The thickness of the substrate is preferably 20 to 1000 μm, more preferably 40 to 500 μm.
The type of resin contained in the base layer is not particularly limited, and examples thereof include materials constituting the above-mentioned temporary support. Among them, the (meth) acrylic resin is preferable as the resin contained in the base layer.
The thickness of the base layer is preferably 0.01 to 5.0 μm, more preferably 0.05 to 3.0 μm.
When the functional layer is a retardation layer, a temporary support whose surface has been subjected to a rubbing treatment may be used as the temporary support. Alternatively, the base layer may be an alignment layer (for example, a resin layer that has been subjected to a rubbing treatment).

(Precursor layer)
The precursor layer is a layer that is placed directly on the temporary support. As will be described later, in the second embodiment, the precursor layer is arranged on the temporary support via another layer.
The precursor layer contains a liquid crystal compound having a polymerizable group (hereinafter, also referred to as “polymerizable liquid crystal compound”).
The type of the polymerizable group is not particularly limited, and examples thereof include a radically polymerizable group and a cationically polymerizable group, including a (meth) acryloyloxy group, a vinyl group, a maleimide group, an acetyl group, a styryl group, an allyl group, an epoxy group, and a group. , Oxetane group.
(Meta) Acryloyloxy group is a general term for acryloyloxy group and methacryloyloxy group.
The number of polymerizable groups contained in the polymerizable liquid crystal compound is not particularly limited, and is preferably 1 to 6 and more preferably 1 to 3.

The polymerizable liquid crystal compound may be a rod-shaped liquid crystal compound or a disk-shaped liquid crystal compound, but a rod-shaped liquid crystal compound is preferable. Examples of the rod-shaped liquid crystal compound include azomethines, azoxys, cyanobiphenyls, cyanophenyl esters, benzoic acid esters, cyclohexanecarboxylic acid phenyl esters, cyanophenylcyclohexanes, cyano-substituted phenylpyrimidins, and alkoxy-substituted phenylpyrimidins. Phenyldioxans, trans, or alkenylcyclohexylbenzonitriles are preferred.
As the liquid crystal compound, not only a small molecule liquid crystal compound but also a high molecular weight liquid crystal compound can be used.

The precursor layer contains a partial structure (phenyl ester structure) represented by the formula (1).
The partial structure represented by the formula (1) may be contained in the above-mentioned polymerizable liquid crystal compound, or may be contained in another compound. Examples of other compounds include surfactants described later.

In formula (1), R represents a substituent. The type of the substituent is not particularly limited, and is a halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom, etc.), alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, alkynyl group, aryl group, hetero. Ring group, cyano group, hydroxyl group, nitro group, carboxyl group, alkoxy group, aryloxy group, silyloxy group, heterocyclic oxy group, acyloxy group, carbamoyloxy group, amino group (including alkylamino group and anilino group), acylamino Group, aminocarbonylamino group, alkoxycarbonylamino group, aryloxycarbonylamino group, sulfamoylamino group, alkyl or arylsulfonylamino group, mercapto group, alkylthio group, arylthio group, heterocyclic thio group, sulfamoyl group, sulfo group , Alkyl or arylsulfinyl group, alkyl or arylsulfonyl group, acyl group, aryloxycarbonyl group, alkoxycarbonyl group, carbamoyl group, aryl or heterocyclic azo group, imide group, phosphino group, phosphinyl group, phosphinyloxy group, Examples thereof include a phosphinylamino group and a silyl group.
n1 represents an integer of 0 to 4, and n2 represents an integer of 0 to 4.
Among them, n1 is preferably 0 to 2, more preferably 0 to 1. n2 is preferably 0 to 2, more preferably 1.
n1 + n2 represents 4 or less. That is, the total of n1 and n2 is 4 or less. Of these, 1 to 2 is preferable, and 1 is preferable.
* Represents the bond position.

In formula (1), n2 represents the number of bonds linked to the benzene ring. For example, when the partial structure represented by the formula (1) is a divalent group, n2 is 1, and the partial structure represented by the formula (2) (a divalent group represented by the formula (2)). ) May be contained in the compound.

As an example in which the partial structure represented by the above formula (1) (or the partial structure represented by the above formula (2)) is contained in the compound, for example, in the following compounds, the broken line portion is the above-mentioned portion. Corresponds to the structure.

As the polymerizable liquid crystal compound having a partial structure represented by the formula (1), the compound represented by the formula (A) is preferable.
Equation (A) P ¹ -L ¹ -ML ² -P ²
In formula (A), P ¹ and P ² each independently represent a hydrogen atom or a polymerizable group, and at least one of P ¹ and P ² represents a polymerizable group. The definition of the polymerizable group is as described above.

L ¹ and L ² each independently represent a single bond or a divalent linking group. The divalent linking group is not particularly limited, but is any one selected from the group consisting of, for example, -O-, -CO-, -NR ^A- , -N = CH-, and a divalent hydrocarbon group. A group of species or a combination of two or more (eg, -CO-O-, -O-2 valent hydrocarbon group-, -O-2-valent hydrocarbon group -O-,-(O-2-valent hydrocarbon group) Hydrocarbon group) _n3- (n3 represents an integer of 2 to 10)). ^RA represents a hydrogen atom or an alkyl group.
Examples of the divalent hydrocarbon group include an alkylene group, an alkenylene group (example: -CH = CH-), an alkynylene group (example: -C≡C-), and an arylene group (example: phenylene group). Can be mentioned. The alkylene group may be linear, branched, or cyclic. The number of carbon atoms thereof is preferably 1 to 10, more preferably 1 to 6, and even more preferably 1 to 4.

M represents a divalent mesogen group having a partial structure represented by the formula (2).
A mesogen group is a functional group that is rigid and has orientation. The mesogen group may be a rod-shaped mesogen group or a disk-shaped mesogen group. The rod-shaped mesogen group is intended to be a mesogen group having a structure in which the main skeleton portion is linear, and the disk-shaped mesogen group is intended to be a mesogen group having a structure in which the main skeleton portion is radially spread.
More specifically, the structure of the mesogen group includes a plurality of groups, directly or 2 groups selected from the group consisting of aromatic ring groups (aromatic hydrocarbon ring groups and aromatic heterocyclic groups) and alicyclic groups. Valuable linking group (eg, -CO-, -O-, -NR ^A- ( ^RA represents a hydrogen atom or an alkyl group), or a group combining these (-CO-O-)) There is a structure connected through.
More specifically, examples of the mesogen group include a group represented by the formula (B).
Equation (B)-(L ³ -L ⁴ ) _m-
^L3 represents a divalent aromatic ring group which may have a substituent or a divalent alicyclic group which may have a substituent.
L ⁴ represents a single bond, -CO-, -O-, -NR ^A- , or a group combining these (eg, -CO-O-). ^RA represents a hydrogen atom or an alkyl group. m represents an integer of 2 or more.
However, at least one of the units represented by m (L ³ -L ⁴ ) represents the partial structure represented by the equation (2).

Examples of the divalent aromatic ring group include a divalent aromatic hydrocarbon ring group (for example, a phenylene group) and a divalent aromatic heterocyclic group.
Examples of the divalent alicyclic group include a cyclohexylene group.
The divalent aromatic ring group or the divalent alicyclic group may further have a substituent. The definition of the substituent is the same as the definition of the substituent represented by R in the formula (1).
For m, an integer of 2 to 5 is preferable, and an integer of 2 to 3 is more preferable.

The precursor layer may contain a compound other than the polymerizable liquid crystal compound.
The polymerizable liquid crystal compound may contain a surfactant.
As the surfactant, a surfactant containing a fluorine atom (fluorine-based surfactant) or a surfactant containing a silicon atom (silicon-based surfactant) is preferable, and a surfactant containing a fluorine atom is more preferable.
The surfactant is preferably a compound having at least two substituents containing a perfluoroalkyl group.
As the substituent containing a perfluoroalkyl group, a group represented by the formula (C) is preferable.
Equation (C) C _p F _{2p + 1} -L ^5- *
L ⁵ represents a divalent linking group. The definition of a divalent linking group is the same as the definition of a divalent linking group represented by L ¹ and L ² . L ⁵ includes -CH _2- , -O-, -CO-, and combinations thereof (for example, -CO-O-, -O-2-valent hydrocarbon group-, -O-2-valent hydrocarbon". Hydrogen groups -O-,-(O-2 valent hydrocarbon groups) _n3- (n3 represents an integer of 2 to 10),-(O-CO-2 valent hydrocarbon groups) _n4- (n4) Represents an integer of 1 to 10.))) is preferable.
p represents an integer of 1 or more. As p, an integer of 1 to 20 is preferable, and an integer of 1 to 10 is more preferable.
The surfactant preferably contains a benzene ring or a triazine ring.
The molecular weight of the surfactant is preferably 3000 or less, more preferably 2000 or less. The lower limit is not particularly limited, but is preferably 300 or more.

The surfactant preferably has a partial structure represented by the above-mentioned formula (1).
As the surfactant, a compound represented by the formula (D) is preferable.
Equation (D) (C _p F _{2p + 1} -L ⁵ ) _q1 -Ar ^1- (L ⁶ -L ⁷ ) _r -Ar ^2- (L ⁵ -C _p F _{2p + 1} ) _q2
^In formula (D), the definitions of p and L5 are as described above.
Ar ¹ represents a q1 + 1 valent benzene ring. The benzene ring may have a substituent other than the group represented by (C _p F _{2p + 1} -L ⁵ ).
Ar ² represents a q2 + 1 valent benzene ring. The benzene ring may have a substituent other than the group represented by (C _p F _{2p + 1} -L ⁵ ).
L ⁶ represents a divalent aromatic ring group which may have a substituent or a divalent alicyclic group which may have a substituent. Examples of the divalent aromatic ring group include a divalent aromatic hydrocarbon ring group (for example, a phenylene group) and a divalent aromatic heterocyclic group. The divalent aromatic ring group or the divalent alicyclic group may further have a substituent. The definition of the substituent is the same as the definition of the substituent represented by R in the formula (1).
L ⁷ represents a single bond, -CO-, -O-, -NR ^A- , or a group combining these (eg, -CO-O-). ^RA represents a hydrogen atom or an alkyl group. n represents an integer of 2 or more.
However, at least one of the units represented by r (L ⁶ -L ⁷ ) represents the partial structure represented by the equation (2).
r represents an integer of 1 to 3. Of these, 1 or 2 is preferable.
q1 and q2 each independently represent an integer of 1 to 5. Of these, an integer of 1 to 3 is preferable.

When the precursor layer contains a surfactant, the content of the surfactant in the precursor layer is not particularly limited, but is preferably 0.01 to 5% by mass, preferably 0, based on the total mass of the polymerizable liquid crystal compound. .1 to 3% by mass is more preferable.
The surfactant may be used alone or in combination of two or more.

The precursor layer may contain a polymerization initiator.
As the polymerization initiator, a photopolymerization initiator capable of initiating a polymerization reaction by irradiation with ultraviolet rays is preferable. Examples of the photopolymerization initiator include α-carbonyl compounds, acidoin ethers, α-hydrocarbon-substituted aromatic acidoin compounds, polynuclear quinone compounds, phenazine compounds, oxadiazole compounds, and compounds having an oxime ester structure. Be done.
When the precursor layer contains a polymerization initiator, the content of the polymerization initiator in the precursor layer is not particularly limited, but is preferably 0.1 to 20% by mass with respect to the total mass of the polymerizable liquid crystal compound. -8% by mass is more preferable.
The polymerization initiator may be used alone or in combination of two or more.

The precursor layer may contain a chiral agent. If the precursor layer contains a chiral agent, a cholesteric phase can be formed.
The type of chiral auxiliary is not particularly limited. The chiral agent may be liquid crystal or non-liquid crystal. Chiral agents generally contain asymmetric carbon atoms. However, an axial asymmetric compound or a planar asymmetric compound that does not contain an asymmetric carbon atom can also be used as a chiral agent. Examples of the axial asymmetric compound or the planar asymmetric compound include binaphthyl, helicene, paracyclophane, and derivatives thereof. The chiral agent may have a polymerizable group.
As the chiral agent, a chiral agent whose spiral-inducing force changes by light irradiation (hereinafter, also referred to as “photosensitive chiral agent”) is preferable. For example, a chiral agent whose spiral-inducing force is reduced by light irradiation and a chiral agent whose spiral-inducing force is increased by light irradiation can be mentioned.
The spiral-inducing force (HTP) of the chiral agent is a factor indicating the spiral orientation ability represented by the following formula (X).
Formula (X) HTP = 1 / (length of spiral pitch (unit: μm) × concentration of chiral agent in precursor layer (mass%)) [μm ^-1 ]
The length of the spiral pitch means the length of the pitch P (= spiral period) of the spiral structure of the cholesteric liquid crystal phase, and can be measured by the method described on page 196 of the Liquid Crystal Handbook (published by Maruzen Co., Ltd.).

Examples of the photosensitive chiral agent include so-called photoreactive chiral agents. The photoreactive chiral agent is a compound having a chiral portion and a photoreactive portion whose structure is changed by light irradiation, and for example, a compound that greatly changes the torsional force of the liquid crystal compound according to the amount of irradiation light.
Examples of photochemical compounds whose structure changes due to light irradiation are photochromic compounds (Kingo Uchida, Masahiro Irie, Chemical Industry, vol.64, 640p, 1999, Kingo Uchida, Masahiro Irie, Fine Chemicals, vol.28 (9), 15p. , 1999) and the like. Further, the structural change means decomposition, addition reaction, isomerization, dimerization reaction, etc. caused by irradiation of the photoreactive site with light, and the structural change may be irreversible. Examples of the chiral site include Hiroyuki Nohira, Review of Chemistry, No. 22 Liquid crystal chemistry, 73p: 1994, corresponds to the asymmetric carbon and the like.

As the photosensitive chiral agent, a compound having at least one photoisomerization site is preferable. The photoisomerization site includes a cinnamoyl site, a chalcone site, an azobenzene site, and a stilbene site in that the absorption of visible light is small, photoisomerization is likely to occur, and the difference in spiral induced force before and after light irradiation is large. Alternatively, a coumarin moiety is preferable, and a cinnamoyl moiety or a chalcone moiety is more preferable.
The photoisomerization site corresponds to a photoreaction site whose structure changes due to light irradiation.

In addition to the above-mentioned components, the precursor layer includes antioxidants, ultraviolet absorbers, sensitizers, stabilizers, plasticizers, chain transfer agents, polymerization inhibitors, defoamers, thickeners, flame retardants, and dispersants. , And other additives such as colorants such as dyes and pigments.

(Procedure of step 1-1)
The method for forming the precursor layer is not particularly limited, but from the viewpoint that the film thickness of the precursor layer can be easily controlled, a composition for forming a precursor layer containing a predetermined component is applied onto the temporary support to temporarily control the film thickness. A method of forming a precursor layer on the support is preferred.
Examples of the components contained in the composition for forming the precursor layer include the components that can be contained in the precursor layer described above.
The composition for forming a precursor layer may contain a solvent. Examples of the solvent include water and organic solvents. Examples of the organic solvent include amides such as N, N-dimethylformamide; sulfoxides such as dimethyl sulfoxide; heterocyclic compounds such as pyridine; hydrocarbons such as benzene and hexane; alkyl halides such as chloroform and dichloromethane; methyl acetate, Esters such as butyl acetate and propylene glycol monoethyl ether acetate; ketones such as acetone, methyl ethyl ketone, cyclohexanone and cyclopentanone; ethers such as tetrahydrofuran and 1,2-dimethoxyethane.

Examples of the method for applying the precursor layer forming composition include a wire bar coating method, an extrusion coating method, a direct gravure coating method, a reverse gravure coating method, and a die coating method.

If necessary, after applying the precursor layer forming composition, a treatment for drying the precursor layer formed on the temporary support may be carried out. By carrying out the drying treatment, the solvent can be removed from the precursor layer.

The film thickness of the precursor layer is not particularly limited, but is preferably 0.1 to 20 μm, more preferably 0.2 to 15 μm.

<Step 2>
In step 2, after the liquid crystal compound in the precursor layer is oriented, the precursor layer is irradiated with light from the surface opposite to the temporary support side of the precursor layer to carry out a curing treatment, and the function is as follows. This is the process of obtaining a layer. More specifically, after orienting the liquid crystal compound in the precursor layer, as shown in FIG. 2, a white arrow indicates from the surface 12a of the precursor layer 12 opposite to the temporary support 10 side. As described above, the precursor layer 12 is subjected to a curing treatment by irradiating it with light. As a result, as shown in FIG. 3, the functional layer 14 is formed on the temporary support 10, and the laminated body 18A is obtained. As described above, in the vicinity of the surface 14a on the side opposite to the temporary support 10 side of the functional layer 14, many phenolic hydroxyl groups are present due to optical Fries rearrangement, and other groups on the surface 14a side of the functional layer 14 are present. Adhesion to the material is improved.
Hereinafter, the procedure of this step will be described in detail.

The method for orienting the liquid crystal compound in the precursor layer is not particularly limited, and examples thereof include a method in which the precursor layer is heat-treated. The conditions of the heat treatment vary depending on the type of the polymerizable liquid crystal compound and the components used, but the heating temperature is preferably 10 to 250 ° C, more preferably 50 to 150 ° C. The heating time is preferably 0.5 to 5 minutes, more preferably 0.5 to 2 minutes.
The orientation state of the liquid crystal compound differs depending on the components used, and when the precursor layer contains a chiral agent, the liquid crystal compound is cholesteric oriented. Further, when a temporary support including an alignment layer is used as the temporary support and the precursor layer does not contain a chiral agent, the liquid crystal compound is homogenically oriented.

Next, the precursor layer in which the liquid crystal compound is oriented is irradiated with light from the surface of the precursor layer opposite to the temporary support side to carry out the curing treatment.
The light applied to the precursor layer includes light having a wavelength of 265 nm. By irradiating the precursor layer with light having a wavelength of 265 nm, the above-mentioned optical Fries rearrangement proceeds.
The irradiation amount of light having a wavelength of 265 nm is 5 mJ / cm ² or more, and 10 mJ / cm ² or more is preferable, and 20 mJ / cm is preferable in that the optical Fries rearrangement proceeds better and the transferability of the optical layer is further improved. ² or more is more preferable. The upper limit is not particularly limited, but in terms of productivity, 500 mJ / cm ² or less is preferable, and 150 mJ / cm ² or less is more preferable.

The light irradiated to the precursor layer may contain light having a wavelength of 265 nm, but ultraviolet rays are preferable because the curing of the precursor layer proceeds more satisfactorily, and light containing light having a wavelength of 365 nm (ultraviolet rays) is preferable. More preferred.
The irradiation amount of light having a wavelength of 365 nm is preferably 20 mJ / cm ² or more, and more preferably 50 mJ / cm ² or more, from the viewpoint that the curing of the precursor layer proceeds more satisfactorily. The upper limit is not particularly limited, but 1500 mJ / cm ² or less is preferable in terms of productivity.

The temperature of the precursor layer at the time of light irradiation is not particularly limited, and is preferably a temperature at which the orientation state of the liquid crystal compound is maintained, for example, preferably 10 to 250 ° C, more preferably 20 to 150 ° C.

By going through the above-mentioned steps 1-1 and 2, the temporary support and the functional layer selected from the group consisting of the cholesteric liquid crystal layer and the retardation layer arranged adjacent to the temporary support are included. A laminate is formed. In this aspect, the functional layer itself corresponds to an optical layer which is a transfer material. That is, the functional layer is transferred from the temporary support onto another substrate.
As will be described later, many phenolic hydroxyl groups derived from optical Fries rearrangements are present on the surface of the functional layer opposite to the temporary support side. Therefore, the functional layer can be transferred onto the base material by contacting the surface of the functional layer on the side opposite to the temporary support side with the base material and then peeling off the temporary support.

When the precursor layer contains a photosensitive chiral agent, the cholesteric liquid crystal layer formed through the above steps has a pitch gradient structure (hereinafter, also referred to as "PG structure") in which the spiral pitch changes in the thickness direction. It is preferable to have.).
For example, when a chiral agent whose spiral-inducing force is lower than that of light irradiation is used as the photosensitive chiral agent, the spiral pitch gradually increases from the temporary support side to the opposite side in the formed cholesteric liquid crystal layer. There is. That is, in the cholesteric liquid crystal layer, the selective reflection wavelength (that is, the wavelength band of the light selectively reflected) gradually becomes a long wavelength from the temporary support side to the opposite side.
The reason why the above structure can be obtained will be described below.
Normally, the light emitted to the precursor layer is absorbed by the material forming the precursor layer. Therefore, when the precursor layer is irradiated with light, the amount of light irradiation gradually decreases from the precursor layer side to the temporary support side. That is, the amount of decrease in HTP of the chiral agent gradually decreases from the precursor layer side to the temporary support side. Therefore, in the region on the side opposite to the temporary support side where the HTP is greatly reduced, the spiral induction is small and the spiral pitch is long, and in the region on the temporary support side where the decrease in HTP is small, the chiral agent originally has HTP. Since the spiral is induced by, the spiral pitch becomes short.
That is, in this case, the cholesteric liquid crystal layer selectively reflects long-wavelength light on the side opposite to the temporary support side, and selectively reflects short-wavelength light on the temporary support side as compared to the upper side. do. Therefore, by using the cholesteric liquid crystal layer having a PG structure in which the spiral pitch changes in the thickness direction, light in a wide wavelength band can be selectively reflected.

When the precursor layer contains a photosensitive chiral agent, the cholesteric liquid crystal layer formed through the above steps has an in-plane pattern of a selective reflection wavelength and a half-value width in the selective reflection wavelength band. You may.
For example, when a chiral agent having a lower spiral-inducing force than light irradiation is used as the photosensitive chiral agent, an exposure mask or the like is used to pattern the amount of light irradiation having a wavelength that lowers the spiral-inducing force of the photosensitive chiral agent. , Spiral pitch patterning can be applied in the plane. In this case, it is possible to form a cholesteric liquid crystal layer that selectively reflects long-wavelength light in a place with a large amount of light irradiation and selectively reflects short-wavelength light in a place with a small amount of light irradiation. Further, it is preferable to carry out the curing treatment by irradiating the precursor layer with light having a wavelength for curing.

The selective reflection wavelength of the cholesteric liquid crystal layer formed as the functional layer and the full width at half maximum in the selective reflection wavelength band may be obtained by the following method.
That is, when the integrated reflectance is measured by the method described later, a spectral waveform of the integrated reflectance, which is a mountain shape (upwardly convex) with the wavelength as the horizontal axis, can be obtained. The average reflectance (arithmetic average) of the maximum and minimum values of the integrated reflectance at this time is obtained, and the value of the wavelength on the short wave side of the two wavelengths at the two intersections of the waveform and the average reflectance is λα (nm). , The value of the wavelength on the long wave side is λβ (nm), and it is calculated by the following formula.
Selective reflection wavelength = (λα + λβ) / 2
Half width = (λβ-λα)
Here, in the case of a sample having low diffuse reflectance and strong specular reflectance (normal reflectance), the waveform of the integrated reflection spectrum of the integrated reflectance may be disturbed in a serrated manner. In such a case, the average reflectance (arithmetic average) of the maximum and minimum values of the mirror reflectance is obtained from the above-mentioned spectral reflectance of the mirror reflectance, and the two wavelengths of the two intersections of the waveform and the average reflectance are obtained. Of these, the selective reflection wavelength may be calculated by the above formula, where the wavelength value on the short wave side is λα (nm) and the wavelength value on the long wave side is λβ (nm).
As another method, a method of measuring the selective reflection wavelength and the full width at half maximum by measuring the transmission spectrum of the sample with Axoscan of Axometrix or the like is exemplified. When the transmission spectrum is measured, a transmission spectrum waveform having a valley shape (convex downward) with the wavelength on the horizontal axis can be obtained. The average reflectance (arithmetic average) of the maximum and minimum values of the transmittance at this time is obtained, and of the two wavelengths at the two intersections of the waveform and the average transmittance, the wavelength value on the short wave side is λα (nm) and the long wave. By setting the value of the wavelength on the side to λβ (nm), the selective reflection wavelength and the half-value range are calculated by the above-mentioned equation.
For the integrated reflectance at wavelength λ, a large integrating sphere device (ILV-471, manufactured by Nippon Spectroscopy Co., Ltd.) was attached to the spectrophotometer (V-550, manufactured by Nippon Spectroscopy Co., Ltd.) so that light was incident on the cholesteric liquid crystal layer surface. It may be measured by an optical trap using the attached one.

The half width of the integrated reflection spectrum of the cholesteric liquid crystal layer is not particularly limited, but is preferably 50 nm or more, more preferably 80 nm or more, still more preferably 100 nm or more. The upper limit is not particularly limited, but it is often 500 nm or less.

Further, the cholesteric liquid crystal layer, which is a functional layer, is derived from the cholesteric liquid crystal phase in the cross section observed with a scanning electron microscope (SEM), and has a bright portion B (bright line) and a dark portion D (dark line) in the thickness direction. A striped pattern in which is alternately laminated is observed.
It is preferable that the cholesteric liquid crystal layer has a wavy structure in at least a part of the bright part and the dark part derived from the cholesteric liquid crystal phase in the cross section observed by SEM.
That is, the cholesteric liquid crystal layer is preferably a layer having a cholesteric liquid crystal structure and having a structure in which the angle formed by the spiral axis and the surface of the cholesteric liquid crystal layer changes periodically. In other words, the cholesteric liquid crystal layer has a cholesteric liquid crystal structure, and the cholesteric liquid crystal structure gives a striped pattern of a bright part B and a dark part D in a cross-sectional view of the cholesteric liquid crystal layer observed by SEM, and a line formed by the dark part. It is preferable that the layer has a periodic change in the angle between the normal line and the surface of the cholesteric liquid crystal layer.
Preferably, the wavy structure includes at least one region M in which the absolute value of the inclination angle of the cholesteric liquid crystal layer with respect to the plane is 5 ° or more in the continuous line of the bright portion B or the dark portion D forming the striped pattern. , A structure in which a peak or valley having an inclination angle of 0 °, which is located closest to the region M in the plane direction, is specified.
A mountain or valley with an inclination angle of 0 ° includes convex and concave points, but if the inclination angle is 0 °, it also includes stair-like and shelf-like points. It is preferable that the wavy structure repeats a plurality of regions M in which the absolute value of the inclination angle is 5 ° or more and the peaks or valleys sandwiching the regions M in the continuous line of the bright portion B or the dark portion D of the striped pattern.

FIG. 4 conceptually shows a cross section of a cholesteric liquid crystal layer having a wavy structure and a PG structure.
As described above, as shown in FIG. 4, when the cross section of the cholesteric liquid crystal layer 14A is observed by SEM, a striped pattern of a bright portion B and a dark portion D is observed. That is, in the cross section of the cholesteric liquid crystal layer 14A, a layered structure in which bright portions B and dark portions D are alternately laminated in the thickness direction is observed.
In the cholesteric liquid crystal layer 14A, two repetitions of the bright portion B and the dark portion D correspond to the spiral pitch. From this, the spiral pitch of the cholesteric liquid crystal layer, that is, the reflective layer can be measured from the SEM cross-sectional view. The two repetitions of the bright part B and the dark part D are, that is, two bright parts and two dark parts.
In the cholesteric liquid crystal layer 14A, since the bright portion B and the dark portion D have a wavy structure (undulation structure), the spiral axis of the liquid crystal compound is tilted when light is incident from the normal direction of the cholesteric liquid crystal layer 14A. Due to the area, part of the incident light is reflected diagonally.
That is, in the cholesteric liquid crystal layer 14A, the bright portion B and the dark portion D have a wavy structure, so that a reflective layer having high diffuse reflectance can be realized.

The cholesteric liquid crystal layer having a wavy structure can be formed by forming the cholesteric liquid crystal layer on a forming surface that is not subjected to an orientation treatment such as rubbing. For example, a cholesteric liquid crystal layer having a wavy structure can be formed by forming a cholesteric liquid crystal layer using a temporary support including a base layer that has not been subjected to a rubbing treatment.
When the cholesteric liquid crystal layer is formed on the base layer that is not subjected to the alignment treatment, there is no orientation restricting force on the liquid crystal compound. Therefore, the orientation direction of the liquid crystal compound on the surface of the base layer varies depending on the physical properties of the base layer. become. When the cholesteric liquid crystal layer is formed in such a state, the spiral axes of the liquid crystal compounds constituting the cholesteric liquid crystal phase are oriented in various directions, and as a result, the striped pattern of the bright portion B and the dark portion D becomes a wavy structure.

When the functional layer is a retardation layer, the in-plane retardation of the retardation layer is not particularly limited, but when the retardation layer functions as a so-called λ / 4 plate, the in-plane retardation at a wavelength of 550 nm is 100 to 160 nm. Is preferable. When the retardation layer functions as a so-called λ / 2 plate, the in-plane retardation at a wavelength of 550 nm is preferably 200 to 320 nm.

<< Second Embodiment >>
As described above, the second embodiment of the production method of the present invention represents an embodiment in which a precursor layer is formed on a temporary support via another layer.
The second embodiment of the manufacturing method of the present invention includes the following steps 1-2 and 2.
Step 1-2: Forming a precursor layer containing a liquid crystal compound having a polymerizable group on the temporary support via another layer Step 2: After orienting the liquid crystal compound in the precursor layer, the precursor A step of irradiating a body layer with light from a surface of the precursor layer opposite to the temporary support side to carry out a curing treatment to obtain a functional layer. Since it is the same as the first embodiment except that it forms a layer, the description thereof will be omitted below, and the differences between the two will be mainly described below.

In step 1-2 of the second embodiment, a precursor layer is formed on the temporary support via another layer.
The types of other layers are not particularly limited, and examples thereof include a cholesteric liquid crystal layer and a retardation layer. In addition to the above layer, examples of the other layer include the above-mentioned base layer, adhesive layer, and pressure-sensitive adhesive layer. As will be described later, the other layers arranged on the temporary support are peeled off from the temporary support as a part of the optical layer and transferred to the base material.
When the other layer is a cholesteric liquid crystal layer, the cholesteric liquid crystal layer may have the above-mentioned PG structure. Further, in the cross section of the cholesteric liquid crystal layer observed by the scanning electron microscope, at least a part of the bright part and the dark part derived from the cholesteric liquid crystal phase may have a wavy structure.
When the other layer is a cholesteric liquid crystal layer and the functional layer is a cholesteric liquid crystal layer, the twist direction of the spiral of the cholesteric liquid crystal layer which is the other layer and the twist of the spiral of the cholesteric liquid crystal layer which is the functional layer. The direction may be the opposite direction or the same direction, but the opposite direction is preferable in terms of excellent reflection characteristics.
Further, when the other layer is a cholesteric liquid crystal layer and the functional layer is a cholesteric liquid crystal layer, the selective reflection wavelength of the cholesteric liquid crystal layer which is the other layer and the selective reflection wavelength of the cholesteric liquid crystal layer which is the functional layer are used. The difference between them is preferably 400 nm or less.

The other layer may be a single layer or a multi-layer. In the case of a multilayer, the layers constituting the multilayer may be layers of the same type (for example, cholesteric liquid crystal layers) or different types of layers (for example, a combination of a cholesteric liquid crystal layer and a retardation layer). You may.

The method for forming the other layer is not particularly limited, and a known method is adopted.

By the above procedure, as shown in FIG. 5, a laminated body 18B having a temporary support 10 and another layer 16 and a functional layer 14 arranged on the temporary support 10 is obtained. In the laminated body 18B, the other two layers 14 and the functional layer 16 correspond to the optical layer 20 which is a transfer material. That is, the optical layer is transferred from the temporary support onto another substrate.

By the procedure of the first embodiment and the second embodiment described above, a laminated body having a temporary support and an optical layer arranged adjacently on the temporary support is obtained.
In both the first embodiment and the second embodiment, the functional layer is arranged at the position farthest from the temporary support in the optical layer.
Further, as described above, many phenolic hydroxyl groups derived from optical Fries rearrangements are present on the surface of the functional layer opposite to the temporary support side.
Therefore, by bringing the surface of the optical layer (specifically, the surface of the functional layer opposite to the temporary support side) into contact with the base material directly or via another layer, the temporary support is peeled off. , An optical member including a base material and an optical layer can be obtained. More specifically, in the laminated body 18A shown in FIG. 3, the surface 14a of the functional layer 14 corresponding to the optical layer is brought into contact with the base material directly or via another layer, and then the temporary support 10 is attached. By peeling off, an optical member including a base material and an optical layer can be obtained. Further, in the laminated body 18B shown in FIG. 5, the surface 20a of the optical layer 20 composed of the functional layer 14 and the other layer 16 is brought into contact with the base material directly or via another layer, and then the optical layer 20 is formed. By peeling off the temporary support 10 at the interface between the temporary support 10 and the temporary support 10, an optical member including a base material and an optical layer can be obtained. In addition, in the form of FIG. 5, the embodiment in which the optical layer is two layers is described, but the optical layer may be three or more layers, and the optical layer may be a single layer or a single layer arranged adjacently on the temporary support. It corresponds to a multi-layered layer. Examples of the method of forming the optical layer into three or more layers include a method of forming a precursor layer on the temporary support via another layer of two layers.
Examples of the other layers include a cholesteric liquid crystal layer, a retardation layer, a base layer, an adhesive layer, and an adhesive layer, as described above. When another layer is arranged on the temporary support, the other layer is transferred onto the base material as a part of the optical layer.

The functional layer can be applied to various uses. For example, when the functional layer is a cholesteric liquid crystal layer, various uses such as a decorative sheet, a light reflecting member, a light diffusing plate, a half mirror, a transparent screen, an image pickup element, a sensor, an optical device, and other optical elements. It is available for. For example, the functional layer in the laminate produced by the production method of the present invention can be used for an optical device having a functional layer and an element that utilizes light transmitted through the functional layer.
The element that utilizes the light transmitted through the functional layer is not particularly limited, and various elements such as an image pickup element and a sensor can be mentioned. At this time, for example, the laminate produced by the manufacturing method of the present invention is attached to an optical filter such as an SC filter (manufactured by Fujifilm) and an IR filter (manufactured by Fujifilm), and the temporary support is peeled off. The functional layer may be used as a decorative sheet. This makes it possible to decorate the image sensor and the sensor and other elements according to the light receiving wavelength.

Further, the functional layer in the laminated body produced by the manufacturing method of the present invention and the image display element may be used as an image display device.
As the image display element, various known image display elements can be used. As an example, a liquid crystal display element, an organic electroluminescence display element, and the like are exemplified.

Further, the functional layer in the laminate produced by the production method of the present invention can also be used for optical element applications. For example, it can be used as a general half mirror and also used as described in paragraph 0017 of JP-A-2017-092021.

Hereinafter, the present invention will be described in more detail based on examples. The materials, amounts, ratios, treatment contents, and treatment procedures shown in the following examples can be appropriately changed as long as they do not deviate from the gist of the present invention. Therefore, the scope of the present invention should not be construed as limiting by the examples shown below.

<Comparative Example 1>
(Preparation of base layer 1)
PET (polyethylene terephthalate) (Cosmo Shine A4100, manufactured by Toyobo Co., Ltd.) was prepared as a substrate having a thickness of 50 μm and used as the transparent support 1. The transparent support 1 corresponds to a so-called temporary support.
On the surface of the transparent support 1 without the easy-adhesive layer, the base layer coating liquid 1 having the following composition was applied with a wire bar coater of # 3.6. Then, the transparent support 1 coated with the base layer coating liquid 1 is dried at 45 ° C. for 60 seconds, and the transparent support 1 subjected to the above drying treatment is 500 mJ / cm using an ultraviolet irradiation device at 25 ° C. The transparent support 1 with a base layer was produced by irradiating with the ultraviolet rays of ² .

(Undercoat layer coating liquid 1)
KAYARAD PET30 (manufactured by Nippon Kayaku Co., Ltd.) 100 parts by mass IRGACURE 907 (manufactured by Ciba Geigy) 3.0 parts by mass KayaCure DETX (manufactured by Nippon Kayaku Co., Ltd.) 1.0 part by mass Surfactant F10 with the following structure 0.01 parts by mass Methyl isobutyl ketone 243 parts by mass

Surfactant F1 (hereinafter referred to as structural formula)

(Preparation of cholesteric liquid crystal layer Ch1)
The components shown below were stirred in a container kept warm at 25 ° C. to prepare a coating liquid Ch1 for a cholesteric liquid crystal layer.

(Cholesteric liquid crystal layer coating liquid Ch1)
Methyl ethyl ketone 125.0 parts by mass Cyclohexanone 18.7 parts by mass Mix of the following rod-shaped liquid crystal compounds 100.0 parts by mass IRGACURE 907 (manufactured by Ciba Geigy) 0.0375 parts by mass Kayacure DETX (manufactured by Nippon Kayaku Co., Ltd.) 0.0125 Parts by mass Chiral agent B with the following structure 6.06 parts by mass Surface active agent with the above structure F1 0.027 parts by mass Surface active agent with the following structure F2 0.067 parts by mass

Rod-shaped liquid crystal compound (hereinafter referred to as structural formula)

The numerical value is mass%. Further, R is a group bonded with an oxygen atom.

Chiral agent B (hereinafter referred to as structural formula)

The chiral agent B is a chiral agent that forms a right-handed spiral. The chiral agent B is a chiral agent having a cinnamate group.

Surfactant F2

The coating liquid Ch1 for the cholesteric liquid crystal layer prepared above was applied to the surface of the transparent support 1 with a base layer on the base layer with a # 12 wire bar coater. Then, the transparent support 1 with an underlying layer coated with the coating liquid Ch1 for the cholesteric liquid crystal layer was dried at 105 ° C. for 60 seconds, and a short wavelength cut filter (TEMPAX, manufactured by Shot) at an oxygen concentration of 200 ppm or less and 85 ° C. The cholesteric liquid crystal layer Ch1 was produced by irradiating the ultraviolet rays of a high-pressure mercury lamp having an irradiation amount of 459 mJ / cm ² at a wavelength of 365 nm and an irradiation amount of 2.4 mJ / cm ² at a wavelength of 265 nm.

(Preparation of cholesteric liquid crystal layer Ch2)
The components shown below were stirred in a container kept warm at 25 ° C. to prepare a coating liquid Ch2 for a cholesteric liquid crystal layer.

(Cholesteric liquid crystal layer coating liquid Ch2)
Methyl ethyl ketone 132.4 parts by mass Cyclohexanone 19.8 parts by mass 100.0 parts by mass of the above rod-shaped liquid crystal compound Kayacure DETX (manufactured by Nippon Kayaku Co., Ltd.) 0.5 parts by mass Chiral agent C 11.87 parts by mass Surfactant F1 0.027 parts by mass of the above structure Surfactant F2 0.067 parts by mass of the above structure

Chiral agent C (hereinafter referred to as structural formula)

The chiral agent C is a chiral agent that forms a left-handed spiral. Further, the chiral agent C is a chiral agent having a cinnamate group.

On the cholesteric liquid crystal layer Ch1, the coating liquid Ch2 for the cholesteric liquid crystal layer prepared above was applied with a # 5 wire bar coater. Then, the transparent support 1 with an underlying layer coated with the coating liquid Ch2 for the cholesteric liquid crystal layer is dried at 105 ° C. for 60 seconds, and the short wavelength cut filter (TEMPAX, Shot Co., Ltd.) has an oxygen concentration of 200 ppm or less and 85 ° C. Cholesteric liquid crystal layer Ch2 was produced by irradiating ultraviolet rays from a high-pressure mercury lamp having an irradiation amount of 459 mJ / cm ² at a wavelength of 365 nm and an irradiation amount of 2.4 mJ / cm ² at a wavelength of 265 nm. The laminate of Example 1 was prepared.

<Comparative Example 2>
Except that the ultraviolet irradiation of the cholesteric liquid crystal layer Ch2 is the ultraviolet irradiation of a high-pressure mercury lamp having an irradiation amount of 50 mJ / cm ² at a wavelength of 365 nm and an irradiation amount of 3.8 mJ / cm ² at a wavelength of 265 nm without using a filter. The cholesteric liquid crystal layer Ch2 was prepared in the same manner as in Comparative Example 1, and the laminated body of Comparative Example 2 was prepared.

<Example 1>
Except that the ultraviolet irradiation of the cholesteric liquid crystal layer Ch2 is the ultraviolet irradiation of a high-pressure mercury lamp having an irradiation amount of 100 mJ / cm ² at a wavelength of 365 nm and an irradiation amount of 7.7 mJ / cm ² at a wavelength of 265 nm without using a filter. The cholesteric liquid crystal layer Ch2 was prepared in the same manner as in Comparative Example 1, and the laminated body of Example 1 was prepared.

<Example 2>
Except that the ultraviolet irradiation of the cholesteric liquid crystal layer Ch2 is the ultraviolet irradiation of a high-pressure mercury lamp having an irradiation amount of 500 mJ / cm ² at a wavelength of 365 nm and an irradiation amount of 38.3 mJ / cm ² at a wavelength of 265 nm without using a filter. The cholesteric liquid crystal layer Ch2 was prepared in the same manner as in Comparative Example 1, and the laminated body of Example 2 was prepared.

<Evaluation>
The table below shows the results of evaluation using each of the laminates produced in Examples and Comparative Examples.
In Examples 1 and 2, the optical layer to be transferred includes a base layer, a cholesteric liquid crystal layer Ch1 and a cholesteric liquid crystal layer Ch2.

(Removability)
PET (Cosmo Shine A4100, manufactured by Toyobo Co., Ltd.) was prepared as a transfer substrate, and the cholesteric liquid crystal layer Ch2 of the laminate was used as an adhesive via an adhesive (SK-2057, manufactured by Soken Chemical Co., Ltd.). The number of defects when the transparent support 1 was peeled off in the direction of 180 degrees at a speed of 5 m / min was evaluated from the following viewpoints. The results are shown in Table 1.
A: There are 0 to 1 defects per square meter due to poor peeling.
B: 2 to 5 defects per square meter due to poor peeling.
C: There are 6 or more defects per square meter due to poor peeling.
Here, it is assumed that the number of defects due to poor peeling is 0 per square meter if the transparent support 1 is peeled off without remaining at the interface between the transparent support 1 and the base layer. Defects due to poor peeling are not the interface between the transparent support 1 and the base layer, but the optical layer that is peeled off at another interface (for example, the interface between the adhesive and the cholesteric liquid crystal layer Ch2) and should be transferred. It refers to the part that remains on the transparent support 1 side.

In Table 1, the column "Irradiation amount 365 nm (mJ / cm ² )" represents the irradiation amount of light having a wavelength of 365 nm.
The “Irradiation amount 265 nm (mJ / cm ² )” column represents the irradiation amount of light having a wavelength of 265 nm.
The "PG structure" column indicates the presence or absence of the PG structure of the obtained cholesteric liquid crystal layer, and "A" indicates that the cholesteric liquid crystal layer has a PG structure, and "B" indicates that the cholesteric liquid crystal layer does not have a PG structure.
The "wavy structure" column indicates the presence or absence of a wavy structure in the obtained cholesteric liquid crystal layer, and "A" indicates that the cholesteric liquid crystal layer has a wavy structure, and "B" indicates that the cholesteric liquid crystal layer does not have a wavy structure.

As shown in the above table, according to the production method of the present invention, a laminate showing a desired effect was obtained.
Above all, it was confirmed that the effect was more excellent when the irradiation amount of light having a wavelength of 265 nm was 10 mJ / cm ² or more.

10 Temporary support 12 Precursor layer 14 Functional layer 14A Cholesteric liquid crystal layer 16 Other layers 18A, 18B Laminated body 20 Optical layer

Claims (10)

Temporary support and
Includes an optical layer, which is adjacently arranged on the temporary support.
The optical layer includes a functional layer selected from the group consisting of a cholesteric liquid crystal layer and a retardation layer.
A method for manufacturing a laminated body, wherein the functional layer is arranged at a position farthest from the temporary support in the optical layer.
A step of forming a precursor layer containing a liquid crystal compound having a polymerizable group directly or via another layer on the temporary support.
After orienting the liquid crystal compound in the precursor layer, the precursor layer is irradiated with light from the surface opposite to the temporary support side of the precursor layer to carry out a curing treatment. Has a process to obtain a functional layer,
The precursor layer contains a partial structure represented by the formula (1).
The light at the time of the light irradiation includes light having a wavelength of 265 nm, and includes light having a wavelength of 265 nm.
A method for producing a laminate, wherein the irradiation amount of light having a wavelength of 265 nm is 5 mJ / cm ² or more.

In formula (1), R represents a substituent. n1 represents an integer of 0 to 4, n2 represents an integer of 0 to 4, and n1 + n2 represents 4 or less. * Represents the bond position. The precursor layer further comprises a surfactant and
The method for producing a laminate according to claim 1, wherein at least one of the liquid crystal compound and the surfactant has the partial structure. The method for producing a laminate according to claim 1 or 2, wherein the functional layer is a cholesteric liquid crystal layer. The precursor layer contains a chiral agent whose spiral-inducing force is changed by the light irradiation.
The method for producing a laminate according to claim 3, wherein the cholesteric liquid crystal layer has a pitch gradient structure in which the spiral pitch changes in the thickness direction. The method for producing a laminate according to claim 4, wherein the half width of the integrated reflection spectrum of the cholesteric liquid crystal layer is 80 nm or more. The laminate according to any one of claims 1 to 5, wherein at least a part of the bright part and the dark part derived from the cholesteric liquid crystal phase has a wavy structure in the cross section of the cholesteric liquid crystal layer observed by the scanning electron microscope. How to make a body. The precursor layer is arranged on the temporary support via the other layer.
The method for producing a laminate according to any one of claims 1 to 6, wherein the other layer is a cholesteric liquid crystal layer. The method for manufacturing a laminate according to claim 7, wherein the twisting direction of the spiral of the cholesteric liquid crystal layer, which is the functional layer, and the twisting direction of the spiral of the cholesteric liquid crystal layer, which is the other layer, are opposite to each other. The method for producing a laminate according to claim 7 or 8, wherein the cholesteric liquid crystal layer, which is the other layer, has a pitch gradient structure in which the spiral pitch changes in the thickness direction. The optical layer in the laminate obtained by the production method according to any one of claims 1 to 9 is brought into contact with the base material directly or via another layer to peel off the temporary support. A method for manufacturing an optical member, which comprises a step of obtaining an optical member including the base material and the optical layer.

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