JP2009300923A - Laminated structure material for preventing forgery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laminated structure material for preventing forgery, which shows an authentication image having high resolution and excellent heat resistance and being hardly forged and which can be hardly applied to other purpose. <P>SOLUTION: The laminated structure material includes an optical stress-sensitive layer, which is a patterned adhesive layer having a plurality of regions having adhesive strength different from each other or a layer exhibiting optical anisotropy by applying stress, and a patterned optically anisotropic layer containing regions different in birefringence in a patterned manner. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention relates to a laminated structure for preventing forgery.

A sticker that displays an image that is difficult to imitate is used to prevent forgery of the article by being affixed to the article, but since it is in a seal form, diversion to a forged article is also conceivable. As a technique for preventing diversion, Patent Document 1 discloses a brittle seal including a partially formed release layer. After forming a partially formed release layer that can peel a part of a partial functional layer on a functional layer made of a plurality of ceramic materials with different refractive indexes for authenticity determination, the peeled part And the display visualized by the difference in the optical characteristics of the peeled portion serves as a mark to prevent diversion. However, laminates having different refractive indexes do not have a latent image that can be clearly discriminated by a polarizing plate or the like, and are not optimal for application to authenticity determination.

Moreover, in patent document 2, in the seal | sticker which performs authenticity determination with the hologram provided on the base material, the surface where the adhesive force of a base material and a hologram formation layer differs is processed by a base material (for example, corona processing). The providing technique is disclosed. Due to the difference in adhesion between the treated part and the non-treated part, the seal is broken when the seal is peeled off. However, holograms have become easier to manufacture with the spread of technology, and holograms for visual observation that are indistinguishable from genuine ones have been manufactured.

A birefringence pattern in which a latent image is visualized by a polarizing plate is one of those proposed as authentic authentication images (Patent Document 3). However, a seal having a birefringence pattern that can withstand application to authenticity determination, has a high resolution and excellent heat resistance, and can prevent diversion to a fake article is not known.
JP-A-8-95491 Japanese Patent Laid-Open No. 9-244519 JP 2007-1130 A

  An object of the present invention is to provide an anti-counterfeit laminated structure that shows an authentication image that has high resolution, excellent heat resistance, and is difficult to counterfeit, and that is difficult to divert.

That is, the present invention provides the following [1] to [9].
[1] A laminated structure including an optical stress sensitive layer and a patterned optically anisotropic layer having regions having different birefringence in a pattern.
[2] The laminated structure according to claim 1, comprising a reflective layer.
[3] The laminated structure according to [1] or [2], wherein the regions having different birefringence are regions having different retardations.
[4] The laminated structure according to any one of [1] to [3], wherein the patterned optically anisotropic layer is produced by a method including the following steps in this order:
(1) preparing a birefringence pattern builder including an optically anisotropic layer containing a polymer having a reactive group;
(2) A step of subjecting the birefringence pattern builder to pattern heat treatment or pattern ionizing radiation irradiation;
(3) A step of reacting or deactivating the remaining reactive groups in the optically anisotropic layer.

[5] The laminated structure according to any one of [1] to [4], wherein the optical stress sensitive layer is a layer that exhibits optical anisotropy by stress.
[6] The laminated structure according to any one of [1] to [5], which has an adhesive layer.
[7] The laminated structure according to any one of [1] to [4], wherein the optical stress sensitive layer is a patterned adhesive layer having a plurality of regions having different adhesive strengths.
[8] The laminated structure according to any one of [1] to [4], wherein the optical stress sensitive layer includes an adhesive layer and a patterned release layer.
[9] The laminated structure according to any one of [6] to [8], which is used as a forgery prevention seal.

The laminated structure which has a birefringence pattern which can prevent diversion is provided by this invention. The laminated structure of the present invention is useful as an anti-counterfeit seal.

Hereinafter, the present invention will be described in detail.
In the present specification, “to” is used to mean that the numerical values described before and after it are included as a lower limit value and an upper limit value.

  In this specification, the “laminated structure” means a structure having a planar shape or a sheet shape. In this invention, it is preferable that a laminated structure is a structure which can adhere | attach or adhere to articles | goods using an adhesive agent or an adhesive especially. In the present invention, it is also preferable that the laminated structure itself has an adhesive layer and has a form having adhesive strength. The adhesive layer may be capable of adhering the laminated structure to the article.

In this specification, the birefringence pattern means a pattern including a plurality of regions having different birefringence. The birefringence pattern usually has a patterned optically anisotropic layer, that is, a layer including a plurality of regions having different birefringence. The regions having different birefringence may be regions having different retardation and / or optical axis directions, and are preferably regions having different retardations. In addition, since the above region is recognized when a birefringence pattern is observed from the normal direction of the laminated structure, the region is divided by a plane parallel to the normal of the laminated structure plane. Good.
In the present specification, retardation or Re represents in-plane retardation. In-plane retardation (Re (λ)) is measured by making light having a wavelength of λ nm incident in the normal direction of the film in KOBRA 21ADH or WR (manufactured by Oji Scientific Instruments). Retardation or Re in this specification means those measured at wavelengths of 611 ± 5 nm, 545 ± 5 nm, and 435 ± 5 nm for R, G, and B, respectively. It means that measured at a wavelength of 5 nm or 590 ± 5 nm.

  In this specification, “substantially” for the angle means that the error from the exact angle is within a range of less than ± 5 °. Furthermore, the error from the exact angle is preferably less than 4 °, more preferably less than 3 °. With regard to retardation, “substantially” means that the retardation is within ± 5%. Furthermore, Re is not substantially 0 means that Re is 5 nm or more. In addition, the measurement wavelength of the refractive index indicates an arbitrary wavelength in the visible light region unless otherwise specified. In the present specification, “visible light” refers to light having a wavelength of 400 to 700 nm.

  In the present specification, the “optical stress sensitive layer” means a layer exhibiting a property capable of optically detecting stress. In the laminated structure of the present invention, the optical stress sensitive layer is provided as a layer for detecting peeling.

  In the present specification, the “retardation disappearance temperature” means the retardation of the optically anisotropic layer at a certain temperature when the temperature of the optically anisotropic layer is increased from 20 ° C. at a rate of 20 ° C. per minute. Means a temperature at which the retardation of the optically anisotropic layer at 20 ° C. is 30% or less.

  In the present specification, “the retardation disappearance temperature is not in a temperature range of 250 ° C. or lower” means that the letter of the optical anisotropic layer is not increased even when the temperature of the optical anisotropic layer is raised to 250 ° C. It means that the foundation does not become 30% or less of the retardation at 20 ° C.

[Birefringence pattern builder]
FIG. 1 is a schematic cross-sectional view of several examples of a birefringence pattern builder. The birefringence pattern builder is a material for producing a birefringence pattern, and a material capable of producing a birefringence pattern through a predetermined process. The birefringence pattern builder shown in FIG. 1A is an example having an optically anisotropic layer 12 on a support 11. The birefringence pattern builder shown in FIG. 1B is an example having an alignment layer 13. When the alignment layer 13 is formed by applying and drying a solution containing a liquid crystal compound as the optically anisotropic layer 12 to form a liquid crystal phase and then polymerizing and fixing by irradiation with heat or ionizing radiation, the liquid crystal compound is used. Functions as a layer to help the orientation of the film.

The birefringence pattern builder shown in FIG. 1C is an example in which a reflective layer 35 is further provided on the support 11. The birefringence pattern builder shown in FIG. 1D is an example having a reflective layer 35 under the support 11. The birefringence pattern builder shown in FIG. 1 (e) is an example having a transfer adhesive layer 14 between the support 11 and the optically anisotropic layer 12 because it is made of a transfer material. The birefringence pattern builder shown in FIG. 1 (f) is an example having a plurality (12F, 12S) of optically anisotropic layers. The birefringence pattern builder shown in FIG. 1G is an example having a reflective layer 35 under the self-supporting optically anisotropic layer 12.

The birefringence pattern builder shown in FIG. 1 (h) is an optical stress-sensitive layer between the support 11 and the optically anisotropic layer 12 of the birefringence pattern builder shown in FIG. It is an example which has the layer 10 which expresses optical anisotropy. Further, the birefringence pattern builder shown in FIG. 1 (i) is an example having a reflective layer in addition to the example shown in FIG. 1 (h).

[Birefringence pattern builder used as transfer material]
FIG. 2 is a schematic sectional view of several examples of the birefringence pattern material of the present invention used as a transfer material. By using a birefringence pattern builder as a transfer material, a birefringence pattern builder having an optically anisotropic layer on a desired support, a birefringence pattern builder having a plurality of optically anisotropic layers, or birefringence An article having a plurality of layers having a pattern can be easily manufactured.

  The birefringence pattern builder shown in FIG. 2A is an example having the optically anisotropic layer 12 on the temporary support 21. The birefringence pattern builder shown in FIG. 2B is an example in which a transfer adhesive layer 14 is further provided on the optically anisotropic layer 12. The birefringence pattern builder shown in FIG. 2C is an example in which a surface protective layer 18 is further provided on the transfer adhesive layer 14. The birefringence pattern builder shown in FIG. 2D is an example in which an alignment layer 22 on the temporary support 21 is further provided between the temporary support 21 and the optically anisotropic layer 12. The birefringence pattern builder shown in FIG. 2 (e) is an example in which a mechanical property control layer 23 is further provided between the temporary support 21 and the alignment layer 22 on the temporary support. The birefringence pattern builder shown in FIG. 2F is an example having a plurality of optically anisotropic layers (12F, 12S). The birefringence pattern builder shown in FIG. 2G is an example having a layer 10 that exhibits optical anisotropy by stress as an optical stress sensitive layer.

[Birefringence pattern]
FIG. 3 is a schematic cross-sectional view of several examples of birefringence patterns obtained by a manufacturing method using a birefringence pattern builder. The birefringence pattern has at least one patterned optically anisotropic layer 112. In the present specification, the “patterned optically anisotropic layer” means “an optically anisotropic layer having regions having different birefringence in a pattern”. The birefringence pattern shown in FIG. 3A is an example composed of only the patterned optically anisotropic layer 112. The exposed portion 112-A and the unexposed portion 112-B shown in the figure have different birefringence. The different birefringence for each region in the patterned optically anisotropic layer may be formed by pattern heating or the like. The birefringence pattern shown in FIG. 3B is an example in which the reflective layer 35, the transfer adhesive layer 14, and the patterned optically anisotropic layer 112 are provided on the support 11 in this order from the support side. The birefringence pattern may have a plurality of patterned optically anisotropic layers. By having a plurality of patterned optically anisotropic layers, a more complicated latent image can be provided.

The birefringence pattern shown in FIG. 3C is an example in which the same pattern is given by pattern exposure after laminating a plurality of optically anisotropic layers. Such an example is useful, for example, for producing a pattern including a region having a large retardation that cannot be produced by a single optically anisotropic layer. The birefringence pattern shown in FIG. 3D is an example in which independent patterns are given to a plurality of optically anisotropic layers. For example, this is a useful example when two or more optically anisotropic layers having different retardation or slow axis directions are provided and independent patterns are desired. The patterns independent from each other include, for example, a process of forming an optically anisotropic layer (including transfer), a process of performing pattern exposure or pattern heating to form regions with different retardation, and a post-processing process such as baking. Can be repeated a plurality of times in this order. The birefringence pattern shown in FIG. 3 (e) is an example in which patterning is performed by a single baking after the necessary number of optical anisotropic layer formation (including transfer) and pattern exposure are alternately performed. By the same method, the necessary number of regions having different retardations can be produced while minimizing the number of bakings with a large process load.
FIG. 3F and FIG. 3G are examples in which a layer 10 that exhibits optical anisotropy by stress as an optical stress sensitive layer is adjacent to the patterned optical anisotropic layer.

[Laminated structure having birefringence pattern]
FIG. 4-6 shows schematic sectional views of examples of the laminated structure of the present invention. The birefringence pattern 5 may be, for example, any one of the birefringence patterns illustrated in FIG.
FIG. 4 shows an example in which a patterned adhesive layer 6 having a plurality of regions having different adhesive strengths as an optical stress sensitive layer is provided on the support side of a birefringent pattern. By sticking with such a patterned adhesive layer, when the laminated structure is peeled off, the latent image due to the birefringence pattern is distorted, making it difficult to divert by reuse. In addition, by using a patterned adhesive layer having an adhesive strength that has a region stronger than the birefringent pattern or a force that breaks the support in the birefringent pattern and a weak region, the birefringence can be obtained when peeling the laminated structure. The pattern can be broken.

FIG. 5 shows an example in which an adhesive layer and a layer including a release layer on a part of the adhesive layer are used as the optical stress sensitive layer. Only the peeling layer portion makes it easy to peel off the pressure-sensitive adhesive layer and the birefringence pattern when peeling the laminated structure, and the latent image due to the birefringence pattern is distorted, making it difficult to divert by reuse. Further, by making the adhesive strength of the adhesive layer stronger than the birefringence pattern or the force that breaks the support in the birefringence pattern, the birefringence pattern is removed when the laminated structure adhered to the article by the adhesive layer is peeled off. Can be broken.

FIG. 6 shows an example in which a layer that exhibits optical anisotropy by stress is used as the optical stress sensitive layer. Since the layer exhibits optical anisotropy due to stress when peeling the laminated structure, the birefringence pattern may be used for another article after peeling the laminated structure adhered or adhered to the article once. Due to the presence of the above-described layer exhibiting optical anisotropy, the same latent image as the latent image before peeling cannot be provided, and as a result, diversion becomes impossible.

[Method for producing birefringence pattern]
The birefringence pattern includes, for example, a step of preparing a birefringence pattern builder having an optically anisotropic layer, and a step of performing processing such as pattern exposure or pattern heating for forming regions having different retardations in this order. Can be produced.
Hereinafter, the birefringence pattern builder and the birefringence pattern manufacturing method will be described in detail. However, the present invention is not limited to this embodiment, and other embodiments can be carried out with reference to the following description and conventionally known methods, and the present invention is limited to the embodiments described below. It is not something.

[Optically anisotropic layer]
The optically anisotropic layer in the birefringence pattern builder is a layer having optical characteristics that are not isotropic, in which there is even one incident direction in which Re is not substantially 0 when the phase difference is measured. The optically anisotropic layer preferably has a retardation disappearance temperature. When the optically anisotropic layer has a retardation disappearance temperature, it is possible to eliminate the retardation of a part of the optically anisotropic layer by, for example, pattern heating. The retardation disappearance temperature is preferably greater than 20 ° C. and 250 ° C. or less, more preferably 40 ° C. to 245 ° C., further preferably 50 ° C. to 245 ° C., and 80 ° C. to 240 ° C. Is most preferred.

  Further, as the optically anisotropic layer in the birefringence pattern builder, it is preferable to use an optically anisotropic layer in which the retardation disappearing temperature rises when the birefringence pattern builder is exposed. As a result, a difference occurs in the retardation disappearance temperature between the exposed portion and the unexposed portion by pattern exposure, and baking is performed at a temperature higher than the retardation disappearance temperature of the unexposed portion and lower than the retardation disappearance temperature of the exposed portion. As a result, only the retardation of the unexposed portion can be selectively lost.

  The optically anisotropic layer in the birefringence pattern builder preferably contains a polymer. By including a polymer, different types of requirements such as birefringence, transparency, solvent resistance, toughness and flexibility can be met. The polymer in the optically anisotropic layer preferably has an unreacted reactive group. This is because it is considered that the unreacted reactive group reacts upon exposure to cause crosslinking of the polymer chain, and as a result, the retardation disappearance temperature is likely to increase.

The method for producing the optically anisotropic layer is not particularly limited, but a solution containing a liquid crystalline compound having at least one reactive group is applied and dried to form a liquid crystal phase, and then polymerized by irradiation with heat or ionizing radiation. Method of immobilizing and preparing; Method of stretching a layer in which a monomer having at least two or more reactive groups is polymerized and immobilizing; Stretching after introducing a reactive group into a polymer layer using a coupling agent A method; or a method of introducing a reactive group using a coupling agent after stretching a layer made of a polymer.
As will be described later, the optically anisotropic layer may be formed by transfer.

[Optically anisotropic layer formed by polymerizing and fixing a composition containing a liquid crystalline compound]
When producing a liquid crystal phase by applying and drying a solution containing a liquid crystalline compound having at least one reactive group as a method for producing an optically anisotropic layer, followed by irradiation with heat or ionizing radiation and fixing by polymerization Is described below. In this production method, it is easy to obtain an optically anisotropic layer having a thin film thickness and an equivalent retardation as compared with a production method of obtaining an optically anisotropic layer by stretching a polymer described later.

[Liquid crystal compounds]
In general, liquid crystal compounds can be classified into a rod type and a disk type from the shape. In addition, there are low and high molecular types, respectively. Polymer generally refers to a polymer having a degree of polymerization of 100 or more (Polymer Physics / Phase Transition Dynamics, Masao Doi, 2 pages, Iwanami Shoten, 1992). In the present invention, any liquid crystal compound can be used, but a rod-like liquid crystal compound or a disk-like liquid crystal compound is preferably used. Two or more kinds of rod-like liquid crystalline compounds, two or more kinds of disc-like liquid crystalline compounds, or a mixture of a rod-like liquid crystalline compound and a disk-like liquid crystalline compound may be used. It is more preferable to use a rod-like liquid crystal compound or a disk-like liquid crystal compound having a reactive group since temperature change and humidity change can be reduced, and at least one of the reactive groups in one liquid crystal molecule is 2 or more. More preferably it is. The liquid crystal compound may be a mixture of two or more, and in that case, at least one preferably has two or more reactive groups.

It is also preferable that the liquid crystal compound has two or more reactive groups having different polymerization conditions. In this case, it is possible to produce an optically anisotropic layer including a polymer having an unreacted reactive group by selecting conditions and polymerizing only a part of plural types of reactive groups. . The polymerization conditions used may be the wavelength range of ionizing radiation used for polymerization immobilization, or the difference in polymerization mechanism used, but preferably a radical reaction group and a cationic reaction that can be controlled by the type of initiator used. A combination of groups is good. A combination in which the radical reactive group is an acrylic group and / or a methacryl group and the cationic group is a vinyl ether group, an oxetane group and / or an epoxy group is particularly preferable because the reactivity can be easily controlled.

Examples of rod-like liquid crystalline compounds include azomethines, azoxys, cyanobiphenyls, cyanophenyl esters, benzoic acid esters, cyclohexanecarboxylic acid phenyl esters, cyanophenylcyclohexanes, cyano-substituted phenylpyrimidines, alkoxy-substituted phenylpyrimidines. , Phenyldioxanes, tolanes and alkenylcyclohexylbenzonitriles are preferably used. Not only the above low-molecular liquid crystalline compounds but also high-molecular liquid crystalline compounds can be used. The polymer liquid crystal compound is a polymer compound obtained by polymerizing a rod-like liquid crystal compound having a low molecular reactive group. The rod-like liquid crystalline compound having a low-molecular reactive group that is particularly preferably used is a rod-like liquid crystalline compound represented by the following general formula (I).
Formula (I): Q ¹ -L ¹ -A ¹ -L ³ -ML ⁴ -A ² -L ² -Q ²
In the formula, Q ¹ and Q ² are each independently a reactive group, and L ¹ , L ² , L ³ and L ⁴ each independently represent a single bond or a divalent linking group. A ¹ and A ² each independently represent a spacer group having 2 to 20 carbon atoms. M represents a mesogenic group.
Hereinafter, the rod-like liquid crystal compound having a reactive group represented by the general formula (I) will be described in more detail. In the formula, Q ¹ and Q ² are each independently a reactive group. The polymerization reaction of the reactive group is preferably addition polymerization (including ring-opening polymerization) or condensation polymerization. In other words, the reactive group is preferably a reactive group capable of addition polymerization reaction or condensation polymerization reaction. Examples of reactive groups are shown below.

Examples of the divalent linking group represented by L ¹ , L ² , L ³ and L ⁴ include —O—, —S—, —CO—, —NR ² —, —CO—O—, and —O—CO. —O—, —CO—NR ² —, —NR ² —CO—, —O—CO—, —O—CO—NR ² —, —NR ² —CO—O—, and NR ² —CO—NR ^2. A divalent linking group selected from the group consisting of-is preferred. R ² is an alkyl group having 1 to 7 carbon atoms or a hydrogen atom. In the formula (I), Q ¹ -L ¹ and Q ² -L ² -are CH ₂ ═CH—CO—O—, CH ₂ ═C (CH ₃ ) —CO—O—, and CH ₂ ═C ( Cl) -CO-O-CO- O- are _{preferable, CH 2 = CH-CO-} O- is most preferable.

A ¹ and A ² represent spacer groups having 2 to 20 carbon atoms. An alkylene group having 2 to 12 carbon atoms, an alkenylene group, and an alkynylene group are preferable, and an alkylene group is particularly preferable. The spacer group is preferably a chain and may contain oxygen atoms or sulfur atoms that are not adjacent to each other. The spacer group may have a substituent and may be substituted with a halogen atom (fluorine, chlorine, bromine), a cyano group, a methyl group, or an ethyl group.
Examples of the mesogenic group represented by M include all known mesogenic groups. In particular, a group represented by the following general formula (II) is preferable.
Formula (II): - (- W 1 -L 5) n -W 2 -
In the formula, W ¹ and W ² each independently represent a divalent cyclic alkylene group or a cyclic alkenylene group, a divalent aryl group or a divalent heterocyclic group, and L ⁵ represents a single bond or a linking group. Specific examples of the linking group include specific examples of groups represented by L ^{1 to} L ⁴ in the formula (I), —CH ₂ —O—, and —O—CH ₂ —. n represents 1, 2 or 3.

W ¹ and W ² include 1,4-cyclohexanediyl, 1,4-phenylene, pyrimidine-2,5-diyl, pyridine-2,5diyl, 1,3,4-thiadiazole-2,5-diyl, 1,3,4-oxadiazole-2,5-diyl, naphthalene-2,6-diyl, naphthalene-1,5-diyl, thiophene-2,5-diyl, pyridazine-3,6-diyl . In the case of 1,4-cyclohexanediyl, there are trans isomers and cis isomers, but either isomer may be used, and a mixture in any proportion may be used. More preferably, it is a trans form. W ¹ and W ² may each have a substituent. Examples of the substituent include a halogen atom (fluorine, chlorine, bromine, iodine), a cyano group, an alkyl group having 1 to 10 carbon atoms (methyl group, ethyl group, propyl group, etc.), and an alkoxy group having 1 to 10 carbon atoms. (Methoxy group, ethoxy group, etc.), C1-10 acyl group (formyl group, acetyl group, etc.), C1-10 alkoxycarbonyl group (methoxycarbonyl group, ethoxycarbonyl group, etc.), carbon atom Examples thereof include an acyloxy group of 1 to 10 (acetyloxy group, propionyloxy group, etc.), nitro group, trifluoromethyl group, difluoromethyl group and the like.
Preferred examples of the basic skeleton of the mesogenic group represented by the general formula (II) are shown below. These may be substituted with the above substituents.

  Examples of the compound represented by the general formula (I) are shown below, but the present invention is not limited thereto. In addition, the compound represented by general formula (I) is compoundable by the method as described in Japanese National Patent Publication No. 11-513019 (WO97 / 00600).

  As another aspect of the present invention, there is an aspect in which a discotic liquid crystal is used for the optically anisotropic layer. The optically anisotropic layer is preferably a layer of a low molecular weight liquid crystal discotic compound such as a monomer or a polymer layer obtained by polymerization (curing) of a polymerizable liquid crystal discotic compound. Examples of the discotic (discotic) compound include C.I. Destrade et al., Mol. Cryst. 71, 111 (1981), benzene derivatives described in C.I. Destrade et al., Mol. Cryst. 122, 141 (1985), Physicslett, A, 78, 82 (1990); Kohne et al., Angew. Chem. 96, page 70 (1984) and the cyclohexane derivatives described in J. Am. M.M. Lehn et al. Chem. Commun. , 1794 (1985), J. Am. Zhang et al., J. Am. Chem. Soc. 116, page 2655 (1994), and azacrown-based and phenylacetylene-based macrocycles. The above discotic (discotic) compounds generally have a discotic nucleus at the center of the molecule, and groups (L) such as linear alkyl groups, alkoxy groups, and substituted benzoyloxy groups are substituted in a radial pattern. In other words, it has liquid crystallinity and generally includes a so-called discotic liquid crystal. However, when such an aggregate of molecules is uniformly oriented, it exhibits negative uniaxiality, but is not limited to this description. Further, in the present invention, it is not necessary that the final product is formed from a discotic compound, for example, the low molecular discotic liquid crystal has a group that reacts with heat, light, or the like. As a result, it may be polymerized or cross-linked by reaction with heat, light or the like, resulting in high molecular weight and loss of liquid crystallinity.

In the present invention, it is preferable to use a discotic liquid crystalline compound represented by the following general formula (III).
Formula (III): D (-LP) _n
In the formula, D is a discotic core, L is a divalent linking group, P is a polymerizable group, and n is an integer of 4 to 12.
In the formula (III), preferred specific examples of the discotic core (D), the divalent linking group (L) and the polymerizable group (P) are (D1) described in JP-A No. 2001-4837, respectively. To (D15), (L1) to (L25), (P1) to (P18), and the disk-shaped core (D), divalent linking group (L) and polymerizable group ( The contents regarding P) can be preferably applied here.
Preferable examples of the discotic compound include compounds described in [0045] to [0055] of JP-A-2007-121986.

The optically anisotropic layer is formed by applying a composition containing a liquid crystal compound (for example, a coating solution) to the surface of an alignment layer described later to obtain an alignment state exhibiting a desired liquid crystal phase, and then changing the alignment state to heat or A layer prepared by fixing by irradiation with ionizing radiation is preferred.
When a discotic liquid crystalline compound having a reactive group is used as the liquid crystalline compound, it may be fixed in any alignment state of horizontal alignment, vertical alignment, inclined alignment, and twist alignment. In the present specification, “horizontal alignment” means that in the case of a rod-like liquid crystal, the molecular long axis is parallel to the horizontal plane of the support. In the case of a disc-like liquid crystal, the disc surface of the core of the disc-like liquid crystal compound. The horizontal plane of the support is parallel, but it is not required to be strictly parallel, and in this specification, it means an orientation with an inclination angle of less than 10 degrees with the horizontal plane. . The inclination angle is preferably 0 to 5 degrees, more preferably 0 to 3 degrees, further preferably 0 to 2 degrees, and most preferably 0 to 1 degree.

  When two or more optically anisotropic layers comprising a composition containing a liquid crystalline compound are laminated, the combination of the liquid crystalline compounds is not particularly limited, and a laminate of all layers made of a discotic liquid crystalline compound, all having rod-like properties. It may be a laminate of a layer made of a liquid crystal compound, a laminate of a layer made of a composition containing a discotic liquid crystal compound and a layer made of a composition containing a rod-like liquid crystal compound. The combination of the alignment states of the layers is not particularly limited, and optically anisotropic layers having the same alignment state may be stacked, or optically anisotropic layers having different alignment states may be stacked.

  The optically anisotropic layer is preferably formed by applying a coating liquid containing a liquid crystalline compound and the following polymerization initiator and other additives onto a predetermined alignment layer described later. As the solvent used for preparing the coating solution, an organic solvent is preferably used. Examples of organic solvents include amides (eg, N, N-dimethylformamide), sulfoxides (eg, dimethyl sulfoxide), heterocyclic compounds (eg, pyridine), hydrocarbons (eg, benzene, hexane), alkyl halides (eg, , Chloroform, dichloromethane), esters (eg, methyl acetate, butyl acetate), ketones (eg, acetone, methyl ethyl ketone), ethers (eg, tetrahydrofuran, 1,2-dimethoxyethane). Alkyl halides and ketones are preferred. Two or more organic solvents may be used in combination.

[Fixation of alignment state of liquid crystalline compounds]
The aligned liquid crystalline compound is preferably fixed while maintaining the alignment state. The immobilization is preferably carried out by a polymerization reaction of a reactive group introduced into the liquid crystal compound. The polymerization reaction includes a thermal polymerization reaction using a thermal polymerization initiator and a photopolymerization reaction using a photopolymerization initiator, and a photopolymerization reaction is more preferable. The photopolymerization reaction may be either radical polymerization or cationic polymerization. Examples of radical photopolymerization initiators include α-carbonyl compounds (described in US Pat. Nos. 2,367,661 and 2,367,670), acyloin ethers (described in US Pat. No. 2,448,828), α-hydrocarbon substituted aromatics. An acyloin compound (described in US Pat. No. 2,722,512), a polynuclear quinone compound (described in US Pat. Nos. 3,046,127 and 2,951,758), a combination of a triarylimidazole dimer and p-aminophenyl ketone (US Pat. No. 3,549,367) Acridine and phenazine compounds (JP-A-60-105667, US Pat. No. 4,239,850) and oxadiazole compounds (US Pat. No. 4,212,970). Examples of the cationic photopolymerization initiator include organic sulfonium salt systems, iodonium salt systems, phosphonium salt systems, and the like. Organic sulfonium salt systems are preferable, and triphenylsulfonium salts are particularly preferable. As counter ions of these compounds, hexafluoroantimonate, hexafluorophosphate, and the like are preferably used.

It is preferable that the usage-amount of a photoinitiator is 0.01-20 mass% of solid content of a coating liquid, and it is further more preferable that it is 0.5-5 mass%. Light irradiation for the polymerization of the liquid crystalline compound is preferably performed using ultraviolet rays. Irradiation energy is preferably ^{10mJ / cm 2 ~10J / cm 2} , further preferably 25~800mJ / cm ^2. Illuminance is preferably 10 to 1,000 / cm ^2, more preferably 20 to 500 mW / cm ^2, further preferably 40~350mW / cm ^2. The irradiation wavelength preferably has a peak at 250 to 450 nm, and more preferably has a peak at 300 to 410 nm. In order to accelerate the photopolymerization reaction, light irradiation may be performed under an inert gas atmosphere such as nitrogen or under heating conditions.

[Fixing of alignment state of liquid crystal compound having radical reactive group and cationic reactive group]
As described above, it is also preferable that the liquid crystalline compound has two or more kinds of reactive groups having different polymerization conditions. In this case, it is possible to produce an optically anisotropic layer including a polymer having an unreacted reactive group by selecting conditions and polymerizing only a part of plural types of reactive groups. . Polymerization particularly suitable when such a liquid crystalline compound is a liquid crystalline compound having a radical reactive group and a cationic reactive group (specific examples are, for example, the aforementioned I-22 to I-25). The immobilization conditions will be described below.

  First, as the polymerization initiator, it is preferable to use only a photopolymerization initiator that acts on a reactive group intended to be polymerized. That is, it is preferable to use only a radical photopolymerization initiator when selectively polymerizing radical reactive groups and only a cationic photopolymerization initiator when selectively polymerizing cationic reactive groups. The amount of the photopolymerization initiator used is preferably 0.01 to 20% by mass, more preferably 0.1 to 8% by mass, and 0.5 to 4% by mass of the solid content of the coating solution. It is particularly preferred.

Next, it is preferable to use ultraviolet rays for light irradiation for polymerization. At this time, if the irradiation energy and / or illuminance is too strong, both the radical reactive group and the cationic reactive group may react non-selectively. Accordingly, the irradiation energy is preferably ^{5mJ / cm 2 ~500mJ / cm 2} , more preferably 10 to 400 mJ / cm ^2, and particularly preferably ^{20mJ / cm 2 ~200mJ / cm 2} . The illuminance is preferably 5 to 500 mW / cm ^2, more preferably 10 to 300 mW / cm ^2, and particularly preferably 20 to 100 mW / cm ^2. The irradiation wavelength preferably has a peak at 250 to 450 nm, and more preferably has a peak at 300 to 410 nm.

  Of the photopolymerization reactions, reactions using radical photopolymerization initiators are inhibited by oxygen, and reactions using cationic photopolymerization initiators are not inhibited by oxygen. Therefore, when a liquid crystal compound having a radical reactive group and a cationic reactive group is used as the liquid crystalline compound and one kind of the reactive group is selectively polymerized, the radical reactive group is selectively polymerized. In some cases, it is preferable to perform light irradiation in an inert gas atmosphere such as nitrogen, and in the case of selectively polymerizing a cationic reactive group, light irradiation is performed under an oxygen-containing atmosphere (for example, in the air). It is preferable.

[Horizontal alignment agent]
In the composition for forming the optically anisotropic layer, compounds represented by general formulas (1) to (3) described in [0068] to [0072] of JP-A-2007-121986 and the following general formula By containing at least one fluorine-containing homopolymer or copolymer using the monomer (4), the molecules of the liquid crystal compound can be substantially horizontally aligned.

In the formula, R represents a hydrogen atom or a methyl group, X represents an oxygen atom or a sulfur atom, Z represents a hydrogen atom or a fluorine atom, m is an integer of 1 to 6, and n is an integer of 1 to 12. Represents. In addition to the fluorine-containing polymer containing the general formula (4), the compounds described in JP-A-2005-206638 and JP-A-2006-91205 can be used as the unevenness improving polymer in coating as a horizontal alignment agent. Are also described in the specification.
The addition amount of the horizontal alignment agent is preferably 0.01 to 20% by mass, more preferably 0.01 to 10% by mass, and particularly preferably 0.02 to 1% by mass of the mass of the liquid crystal compound. In addition, the compounds represented by the general formulas (1) to (4) may be used alone or in combination of two or more.

[Optically anisotropic layer produced by stretching]
The optically anisotropic layer may be prepared by stretching a polymer. As described above, the optically anisotropic layer preferably has at least one unreacted reactive group. However, when preparing such a polymer, the polymer having a reactive group may be stretched in advance. Alternatively, a reactive group may be introduced into the optically anisotropic layer after stretching using a coupling agent or the like. Features of the optically anisotropic layer obtained by the stretching method include low cost and self-supporting property (no support is required for forming and maintaining the optically anisotropic layer).

[Post-treatment of optically anisotropic layer]
Various post-treatments may be performed in order to modify the produced optically anisotropic layer. Examples of post-treatment include corona treatment for improving adhesion, addition of a plasticizer for improving flexibility, addition of a thermal polymerization inhibitor for improving storage stability, and a coupling treatment for improving reactivity. It is done. Further, when the polymer in the optically anisotropic layer has an unreacted reactive group, addition of a polymerization initiator corresponding to the reactive group is also an effective modifying means. For example, adding a radical photopolymerization initiator to an optically anisotropic layer obtained by polymerizing and fixing a liquid crystalline compound having a cationic reactive group and a radical reactive group using a cationic photopolymerization initiator Thus, the reaction of an unreacted radical reactive group when pattern exposure is performed later can be promoted. Examples of the means for adding the plasticizer and the photopolymerization initiator include a means for immersing the optically anisotropic layer in a solution of the corresponding additive and a solution of the corresponding additive on the optically anisotropic layer. And means for infiltration. In addition, when another layer is applied on the optically anisotropic layer, an additive may be added to the coating solution of the layer and immersed in the optically anisotropic layer.

[Birefringence pattern builder]
The birefringence pattern builder is a material for producing a birefringence pattern, and a material capable of obtaining a birefringence pattern through a predetermined process. The birefringence pattern builder may be usually a film or a sheet. In addition to the optically anisotropic layer described above, the birefringence pattern builder may have a functional layer capable of imparting various secondary functions. Examples of the functional layer include a support, an alignment layer, a reflective layer, and a back adhesive layer. In addition, a birefringence pattern builder used as a transfer material or a birefringence pattern builder made using a transfer material may have a temporary support, a transfer adhesive layer, or a mechanical property control layer. Good.

[Support]
The birefringence pattern builder may have a support for the purpose of maintaining mechanical stability. The support used for the birefringence pattern builder is not particularly limited and may be rigid or flexible, but a support suitable for adhesion or adhesion to an article in which the laminated structure of the present invention is used is preferable. . The rigid support is not particularly limited, but is a known glass plate such as a soda glass plate having a silicon oxide film on its surface, a low expansion glass, a non-alkali glass, a quartz glass plate, a metal such as an aluminum plate, an iron plate, or a SUS plate. A board, a resin board, a ceramic board, a stone board, etc. are mentioned. There are no particular limitations on the flexible support, but cellulose esters (eg, cellulose acetate, cellulose propionate, cellulose butyrate), polyolefins (eg, norbornene polymers), poly (meth) acrylic acid esters (eg, polymethyl) Methacrylate), polycarbonate, polyester and polysulfone, norbornene polymers and other plastic films, paper, aluminum foil, cloth and the like. In view of ease of handling, the thickness of the rigid support is preferably 100 to 3000 μm, and more preferably 300 to 1500 μm. As a film thickness of a flexible support body, 3-500 micrometers is preferable and 10-200 micrometers is more preferable. The support preferably has heat resistance sufficient not to be colored or deformed by baking to be described later. Further, the support may also serve as a reflection layer described later.

[Alignment layer]
As described above, an alignment layer may be used for forming the optically anisotropic layer. The alignment layer is generally provided on a support or temporary support or an undercoat layer coated on the support or temporary support. The alignment layer functions so as to define the alignment direction of the liquid crystal compound provided thereon. The orientation layer may be any layer as long as it can impart orientation to the optically anisotropic layer. Preferred examples of the alignment layer include a rubbing treatment layer of an organic compound (preferably a polymer), an oblique deposition layer of an inorganic compound, and a layer having a microgroove, and ω-tricosanoic acid, dioctadecylmethylammonium chloride and stearyl. Examples include a cumulative film formed by Langmuir-Blodgett method (LB film) such as methyl acid, or a layer in which a dielectric is oriented by applying an electric field or a magnetic field.

  Examples of organic compounds for the alignment layer include polymethyl methacrylate, acrylic acid / methacrylic acid copolymer, styrene / maleimide copolymer, polyvinyl alcohol, poly (N-methylolacrylamide), polyvinylpyrrolidone, styrene / vinyltoluene. Copolymer, chlorosulfonated polyethylene, nitrocellulose, polyvinyl chloride, chlorinated polyolefin, polyester, polyimide, vinyl acetate / vinyl chloride copolymer, ethylene / vinyl acetate copolymer, carboxymethyl cellulose, polyethylene, polypropylene, polycarbonate, etc. And polymers such as silane coupling agents. Examples of preferable polymers include polyimide, polystyrene, polymers of styrene derivatives, gelatin, polyvinyl alcohol, and alkyl-modified polyvinyl alcohol having an alkyl group (preferably having 6 or more carbon atoms).

  A polymer is preferably used for forming the alignment layer. The type of polymer that can be used can be determined according to the orientation (particularly the average tilt angle) of the liquid crystal compound. For example, in order to align the liquid crystalline compound horizontally, a polymer that does not decrease the surface energy of the alignment layer (ordinary alignment polymer) is used. Specific types of polymers are described in various documents about liquid crystal cells or optical compensation sheets. For example, polyvinyl alcohol or modified polyvinyl alcohol, a copolymer with polyacrylic acid or polyacrylate, polyvinyl pyrrolidone, cellulose, or modified cellulose are preferably used. The alignment layer material may have a functional group capable of reacting with the reactive group of the liquid crystal compound. The reactive group can be introduced by introducing a repeating unit having a reactive group in the side chain or as a substituent of a cyclic group. It is more preferable to use an alignment layer that forms a chemical bond with the liquid crystal compound at the interface. Such an alignment layer is described in JP-A-9-152509, and acid chloride or Karenz MOI (manufactured by Showa Denko KK). The modified polyvinyl alcohol in which an acrylic group is introduced into the side chain by using The thickness of the alignment layer is preferably 0.01 to 5 μm, and more preferably 0.05 to 2 μm. The alignment layer may have a function as an oxygen blocking film.

  A polyimide film (preferably fluorine atom-containing polyimide) widely used as an alignment layer for LCD is also preferable as the organic alignment layer. This is a polyamic acid (for example, LQ / LX series manufactured by Hitachi Chemical Co., Ltd., SE series manufactured by Nissan Chemical Co., Ltd., etc.) is applied to the support surface and baked at 100 to 300 ° C. for 0.5 to 1 hour. And then obtained by rubbing.

  Moreover, the rubbing process can utilize a processing method widely adopted as a liquid crystal alignment process of LCD. That is, a method of obtaining the orientation by rubbing the surface of the orientation layer in a certain direction using paper, gauze, felt, rubber, nylon, polyester fiber or the like can be used. Generally, it is carried out by rubbing several times using a cloth or the like in which fibers having a uniform length and thickness are planted on average.

Moreover, as a vapor deposition material for the inorganic oblique vapor deposition film, SiO ₂ is representative, and metal oxides such as TiO ₂ and ZnO ₂ , fluorides such as MgF ₂ , and metals such as Au and Al. The metal oxide can be used as an oblique deposition material as long as it has a high dielectric constant, and is not limited to the above. The inorganic oblique deposition film can be formed using a deposition apparatus. An inorganic oblique vapor deposition film can be formed by fixing the film (support) and performing vapor deposition, or moving the long film and performing continuous vapor deposition.

[Reflective layer]
The birefringence pattern builder may have a reflective layer. Although it does not specifically limit as a reflection layer, For example, metal layers, such as aluminum and silver, are mentioned.

[Two or more optically anisotropic layers]
The birefringence pattern builder may have two or more optically anisotropic layers. Two or more optically anisotropic layers may be adjacent to each other in the normal direction, or another functional layer may be sandwiched therebetween. Two or more optically anisotropic layers may have almost the same retardation or different retardations. Further, the slow axis directions may be in substantially the same direction, or may be in different directions.

[Production method of birefringence pattern builder]
The method for producing the birefringence pattern builder is not particularly limited, but for example, an optically anisotropic layer is directly formed on the support, and another birefringence pattern builder is used as a transfer material for optical on the support. Self-supporting optical anisotropy layer forming other functional layer on self-supporting optical anisotropy layer, forming an anisotropic layer as a self-supporting optical anisotropic layer And a method such as bonding to a support. Among these, from the point of not restricting the physical properties of the optically anisotropic layer, a method of directly forming the optically anisotropic layer on the support and a transfer material are used to transfer the optically anisotropic layer onto the support. A method is preferable, and a method of transferring an optically anisotropic layer onto a support using a transfer material is more preferable because there are few restrictions on the support.

As a method for producing a birefringence pattern builder comprising two or more optically anisotropic layers, another birefringence pattern builder is used as a transfer material, in which an optically anisotropic layer is directly formed on a birefringence pattern builder. And a method of transferring the optically anisotropic layer onto the birefringence pattern builder. Among these, a method of transferring an optically anisotropic layer onto a birefringence pattern builder using a birefringence pattern builder as a transfer material is more preferable.
The birefringence pattern builder used as a transfer material will be described below. Note that the birefringence pattern builder used as a transfer material may be referred to as a “birefringence pattern builder” in Examples and the like to be described later.

[Temporary support]
The birefringence pattern builder used as a transfer material preferably has a temporary support. The temporary support may be transparent or opaque and is not particularly limited. Examples of polymers constituting the temporary support include cellulose esters (eg, cellulose acetate, cellulose propionate, cellulose butyrate), polyolefins (eg, norbornene-based polymers), poly (meth) acrylic acid esters (eg, poly Methyl methacrylate), polycarbonate, polyester and polysulfone, norbornene-based polymers. For the purpose of inspecting optical properties in the production process, the transparent support is preferably a transparent and low birefringent material, and from the viewpoint of low birefringence, cellulose ester and norbornene are preferred. As a commercially available norbornene-based polymer, Arton (manufactured by JSR Co., Ltd.), Zeonex, Zeonore (manufactured by Nippon Zeon Co., Ltd.), or the like can be used. Inexpensive polycarbonate, polyethylene terephthalate, and the like are also preferably used.

[Transfer adhesive layer]
The transfer material preferably has a transfer adhesive layer. The transfer adhesive layer is not particularly limited as long as it is transparent, uncolored, and has sufficient transferability, and examples thereof include a photosensitive resin layer, an adhesive layer using an adhesive, a pressure-sensitive resin layer, and a heat-sensitive resin layer. However, a photosensitive or heat-sensitive resin layer is desirable from the viewpoint of baking resistance.

  The photosensitive resin layer is made of a photosensitive resin composition, and may be positive type or negative type, and is not particularly limited, and a commercially available resist material can also be used. When used as a transfer adhesive layer, it is preferable to exhibit adhesiveness by light irradiation. The photosensitive resin layer is preferably formed from a resin composition containing at least a polymer, a monomer or an oligomer, and a photopolymerization initiator or a photopolymerization initiator system. Regarding the polymer, monomer or oligomer, and photopolymerization initiator or photopolymerization initiator system, the description of [0082] to [0085] of JP-A-2007-121986 can be referred to.

  The photosensitive resin layer preferably contains an appropriate surfactant from the viewpoint of effectively preventing unevenness. As the surfactant, reference can be made to the descriptions of [0095] to [0105] of JP-A-2007-121986.

As the pressure-sensitive adhesive for the pressure-sensitive adhesive layer, for example, those having excellent optical transparency and exhibiting appropriate wettability, cohesiveness and adhesive pressure-sensitive adhesive properties are preferable. Specific examples include pressure-sensitive adhesives that are appropriately prepared using a polymer such as an acrylic polymer, silicone polymer, polyester, polyurethane, polyether, and synthetic rubber as a base polymer. Control of the adhesive properties of the pressure-sensitive adhesive layer can be achieved by, for example, controlling the degree of crosslinking and molecular weight depending on the composition and molecular weight of the base polymer forming the pressure-sensitive adhesive layer, the crosslinking method, the content ratio of the crosslinkable functional group, the blending ratio of the crosslinking agent, etc. It can be suitably performed by a conventionally known method such as adjustment.

The pressure-sensitive resin layer is not particularly limited as long as adhesiveness is exhibited by applying pressure, and rubber-based, acrylic-based, vinyl ether-based, and silicone-based pressure-sensitive adhesives can be used as the pressure-sensitive adhesive. In the production stage and coating stage of adhesives, solvent-based adhesives, non-aqueous emulsion adhesives, water-based emulsion adhesives, water-soluble adhesives, hot melt adhesives, liquid curable adhesives, and delayed A tack-type adhesive can be used. The rubber-based pressure-sensitive adhesive is disclosed in New Polymer Library 13 “Adhesion Technology”, Kobunshi Publishing Co., Ltd. 41 (1987). The vinyl ether-based pressure-sensitive adhesive includes those having a main component of an alkyl vinyl ether polymer having 2 to 4 carbon atoms, vinyl chloride / vinyl acetate copolymer, vinyl acetate polymer, polyvinyl butyral and the like mixed with a plasticizer. As the silicone-based pressure-sensitive adhesive, a rubber-like siloxane can be used to give film formation and film condensing power, and a resin-like siloxane can be used to give stickiness and adhesion.

The heat-sensitive resin layer is not particularly limited as long as it exhibits adhesiveness by applying heat, and examples of the heat-sensitive adhesive include hot-melt compounds and thermoplastic resins. Examples of the heat-meltable compound include low molecular weight products of thermoplastic resins such as polystyrene resin, acrylic resin, styrene-acrylic resin, polyester resin, and polyurethane resin, carnauba wax, molasses, candelilla wax, rice wax, and Plant waxes such as aucuric wax, beeswax, insect wax, shellac, and animal waxes such as whale wax, paraffin wax, microcrystalline wax, polyethylene wax, Fischer-Tropsch wax, ester wax, and oxidation Examples include various waxes such as petroleum waxes such as waxes, and mineral waxes such as montan wax, ozokerite, and ceresin wax. Furthermore, rosin derivatives such as rosin, hydrogenated rosin, polymerized rosin, rosin modified glycerin, rosin modified maleic resin, rosin modified polyester resin, rosin modified phenolic resin and ester gum, phenol resin, terpene resin, ketone resin, cyclopentadiene Examples thereof include resins, aromatic hydrocarbon resins, aliphatic hydrocarbon resins, and alicyclic hydrocarbon resins.

  These heat-meltable compounds preferably have a molecular weight of usually 10,000 or less, particularly 5,000 or less and a melting point or softening point in the range of 50 to 150 ° C. These hot melt compounds may be used alone or in combination of two or more. Examples of the thermoplastic resin include ethylene copolymers, polyamide resins, polyester resins, polyurethane resins, polyolefin resins, acrylic resins, and cellulose resins. Of these, ethylene copolymers and the like are particularly preferably used.

[Mechanical property control layer]
It is preferable to form a mechanical property control layer between the temporary support and the optically anisotropic layer of the transfer material in order to control the mechanical properties and the uneven followability. As the mechanical property control layer, those exhibiting flexible elasticity, those softened by heat, those exhibiting fluidity by heat, and the like are preferable, and a thermoplastic resin layer is particularly preferable. As the component used for the thermoplastic resin layer, organic polymer materials described in JP-A-5-72724 are preferable. It is particularly preferable that the softening point by the measurement method is selected from organic polymer substances having a temperature of about 80 ° C. or less. Specifically, polyolefins such as polyethylene and polypropylene, ethylene copolymers such as ethylene and vinyl acetate or saponified products thereof, ethylene and acrylic acid esters or saponified products thereof, polyvinyl chloride, vinyl chloride and vinyl acetate and saponified products thereof. Vinyl chloride copolymer such as fluoride, polyvinylidene chloride, vinylidene chloride copolymer, polystyrene, styrene copolymer such as styrene and (meth) acrylic acid ester or saponified product thereof, polyvinyl toluene, vinyl toluene and (meta ) Vinyl toluene copolymer such as acrylic ester or saponified product thereof, poly (meth) acrylic ester, (meth) acrylic ester copolymer such as butyl (meth) acrylate and vinyl acetate, vinyl acetate copolymer Combined nylon, copolymer nylon, N-alkoxy Chill nylon, and organic polymeric polyamide resins such as N- dimethylamino nylon.

[Middle layer]
In the transfer material, it is preferable to provide an intermediate layer for the purpose of preventing mixing of components during application of a plurality of application layers and during storage after application. As the intermediate layer, it is preferable to use an oxygen barrier film having an oxygen barrier function described in JP-A-5-72724 as an “isolation layer” or the alignment layer for forming the optical anisotropy. Of these, a layer formed by mixing polyvinyl alcohol or polyvinylpyrrolidone and one or more of these modified products is particularly preferable. The thermoplastic resin layer, the oxygen blocking film, and the alignment layer can also be used.

[Layer Formation Method]
Each layer such as an optically anisotropic layer, a photosensitive resin layer, a transfer adhesive layer, an adhesive layer described later and an orientation layer formed as desired, a thermoplastic resin layer, a mechanical property control layer, and an intermediate layer are formed by dip coating, air It can be formed by coating by a knife coating method, spin coating method, slit coating method, curtain coating method, roller coating method, wire bar coating method, gravure coating method or extrusion coating method (US Pat. No. 2,681,294). . Two or more layers may be applied simultaneously. The methods for simultaneous application are described in US Pat. Nos. 2,761,791, 2,941,898, 3,508,947, and 3,526,528 and Yuji Harasaki, Coating Engineering, page 253, Asakura Shoten (1973).
In addition, when applying a layer (for example, a transfer adhesive layer) to be applied on the optically anisotropic layer, by adding a plasticizer or a photopolymerization initiator to the coating solution, the optical by immersion of these additives is added. The anisotropic layer may be modified at the same time.

[Method of transferring transfer material onto transfer material]
The method for transferring the transfer material onto a transfer material such as a support (substrate) is not particularly limited, and the method is not particularly limited as long as the optically anisotropic layer can be transferred onto the substrate. For example, a transfer material formed in a film shape can be attached by pressing or thermocompression bonding with a roller or flat plate heated and / or pressurized using a laminator with the transfer adhesive layer surface side of the transfer material surface side. . Specific examples include laminators and laminating methods described in JP-A-7-110575, JP-A-11-77942, JP-A-2000-334836, and JP-A-2002-148794. From this point of view, it is preferable to use the method described in JP-A-7-110575.
Examples of the material to be transferred include a support, a laminate including a support and another functional layer, or a birefringence pattern builder.

[Transfer process]
After transferring the birefringence pattern transfer material onto the transfer material, the temporary support may or may not be peeled off. However, when it does not peel, it is preferable that the temporary support has transparency suitable for subsequent pattern exposure, heat resistance that can withstand baking, and the like. Further, there may be a step of removing unnecessary layers transferred together with the optically anisotropic layer. For example, when a copolymer of polyvinyl alcohol and polyvinyl pyrrolidone is used as the alignment layer, the layer above the alignment layer can be removed by development with a weak alkaline aqueous developer. As a development method, a known method such as paddle development, shower development, shower & spin development, dip development or the like can be used. The liquid temperature of the developer is preferably 20 ° C. to 40 ° C., and the pH of the developer is preferably 8 to 13.

  Further, after transfer, another layer may be formed on the surface after the temporary support is peeled off or the unnecessary layer is removed as necessary. Alternatively, the transfer material may be transferred to the surface after the temporary support is removed or the unnecessary layer is removed as necessary. The transfer material used at this time may be the same as or different from the transfer material previously transferred. Further, the slow axis of the optically anisotropic layer of the transfer material previously transferred and the optically anisotropic layer and slow axis of the newly transferred transfer material may be in the same direction or in different directions. As described above, transferring a plurality of optically anisotropic layers means that a birefringence pattern having a large retardation and a slow axis having a large retardation formed by laminating a plurality of optically anisotropic layers having the same slow axis direction. This is useful for producing a special birefringence pattern in which a plurality of layers having different directions are laminated.

[Preparation of birefringence pattern]
Using the birefringence pattern builder, a process of pattern heat treatment or pattern ionizing radiation irradiation, and a process of reacting or deactivating the remaining unreacted reactive groups in the optically anisotropic layer in this order A birefringence pattern can be produced by performing the method including the method. In particular, when the optically anisotropic layer has a retardation disappearance temperature and the retardation disappearance temperature is increased by irradiation with ionizing radiation (or heat treatment below the retardation disappearance temperature), a birefringence pattern can be easily produced. it can.

  Examples of the patterning ionizing radiation irradiation include exposure (pattern exposure). Thereafter, as a step of reacting or deactivating the remaining unreacted reactive groups in the optically anisotropic layer, a full exposure or a full heat treatment (baking) may be performed. In order to save costs, it is preferable that heating to a temperature higher than the retardation disappearance temperature of the unexposed portion and lower than the retardation disappearance temperature of the exposed portion also serves as a heat treatment for the reaction as it is.

  As the pattern-like heat treatment, heating of a partial region is first performed at a temperature close to the retardation disappearance temperature to lower or eliminate the retardation, and then the temperature in the optically anisotropic layer is lower than the retardation disappearance temperature. There is also a technique for obtaining a birefringence pattern by performing a process (full exposure or full heating) of reacting or deactivating the remaining unreacted reactive groups. In this case, it is possible to obtain a pattern in which only the previously heated portion has lost retardation.

[Pattern exposure]
Pattern exposure for producing a birefringence pattern is performed so as to expose a region where birefringence is to be left in the birefringence pattern builder. The retardation disappearance temperature rises in the optically anisotropic layer in the exposed area. As a pattern exposure method, contact exposure using a mask, proxy exposure, projection exposure, or the like may be used, or direct drawing may be performed by focusing on a predetermined position without using a mask using a laser or an electron beam. The irradiation wavelength of the light source for the exposure preferably has a peak at 250 to 450 nm, and more preferably has a peak at 300 to 410 nm. In the case where a step is simultaneously formed by the photosensitive resin layer, it is also preferable to irradiate light in a wavelength region that can cure the resin layer (eg, 365 nm, 405 nm, etc.). Specifically, an ultrahigh pressure mercury lamp, a high pressure mercury lamp, a metal halide lamp, a blue laser, and the like can be given. Usually 3~2000mJ / cm ² about the preferred amount of exposure, and more preferably 5~1000mJ / cm ² or so, more preferably 10 to 500 mJ / cm ² or so, and most preferably at about 10 to 100 mJ / cm ² .

  A new birefringence pattern transfer material may be transferred onto a laminate obtained by pattern exposure of the birefringence pattern builder, and then a new pattern exposure may be performed. In this case, the first and second unexposed areas (normally the lowest retardation value), the first exposed area and the second unexposed area, and the first and second time. The retardation value remaining after baking can be effectively changed in an area that is an exposed area (usually the highest retardation value). It should be noted that the region that is the unexposed portion at the first time and the exposed portion at the second time is considered to be the same as the region that is the exposed portion at the first time and the second time by the second exposure. Similarly, four or more regions can be easily formed by alternately performing transfer and pattern exposure three times and four times.

[Entire heat treatment (bake)]
A birefringence pattern can be prepared by heating the birefringence pattern builder subjected to pattern exposure to 50 ° C. or higher and 400 ° C. or lower, preferably 80 ° C. or higher and 400 ° C. or lower. When the retardation disappearance temperature before exposure of the optical anisotropic layer of the birefringence pattern builder used for birefringence pattern fabrication is T1 [° C.] and the retardation disappearance temperature after exposure is T2 [° C.] (retardation) When the disappearing temperature is not in the temperature range of 250 ° C. or lower, T2 = 250), and the baking temperature is preferably T1 ° C. or higher and T2 ° C. or lower, more preferably (T1 + 10) ° C. or higher and (T2-5) ° C. or lower, Most preferable is (T1 + 20) ° C. or higher and (T2-10) ° C. or lower.
Baking reduces the retardation of the unexposed area in the birefringence pattern builder, while the exposed area where the retardation disappearance temperature has increased in the previous pattern exposure has little or no decrease in retardation. As a result, the retardation of the unexposed area becomes smaller than that of the exposed area, and a birefringence pattern (patterned optically anisotropic layer) is produced.

  Alternatively, a new birefringence pattern transfer material may be transferred onto the baked birefringence pattern material, and then a new pattern exposure and baking may be performed. In this case, the first and second unexposed areas, the first exposed area and the second unexposed area, the first unexposed area and the second exposed area ( The retardation of the first unexposed portion has already disappeared by baking), and the retardation value remaining after the second baking can be effectively changed in the first and second exposed regions. This method is useful when, for example, two regions having birefringences having different slow axis directions are not overlapped with each other.

[Pattern heat treatment (thermal pattern writing)]
The heating temperature at the time of the patterned heat treatment is not particularly limited as long as it causes a difference in the retardation between the heated part and the non-heated part. In particular, when the retardation of the heating part is desired to be substantially 0 nm, it is preferable to heat at a temperature equal to or higher than the retardation disappearance temperature of the optically anisotropic layer of the birefringence pattern builder used. On the other hand, the heating temperature is preferably less than the temperature at which the optically anisotropic layer is burned or colored. In general, heating at about 120 ° C. to 260 ° C. may be performed, 150 ° C. to 250 ° C. is more preferable, and 180 ° C. to 230 ° C. is more preferable.

  A method for heating a part of the birefringence pattern builder is not particularly limited, but a method in which the heating body is brought into contact with the birefringence pattern builder, or a method in which the heating body is positioned very close to the birefringence pattern builder. And a method of partially heating the birefringence pattern builder using heat mode exposure.

[Full-surface heat treatment (baking) at a temperature below the retardation disappearance temperature or reaction treatment by full-surface exposure]
In the optically anisotropic layer that has been subjected to the patterned heat treatment, the region where the heat treatment has not been performed has an unreacted reactive group while having retardation, and is still in an unstable state. In order to react or deactivate the unreacted reactive groups remaining in the untreated region, it is preferable to perform a heat treatment or a reaction treatment by a full exposure.

  The reaction treatment by the overall heat treatment is a temperature lower than the retardation disappearance temperature of the optically anisotropic layer of the birefringence pattern builder used, and the temperature at which the reaction or deactivation of the unreacted reactive group proceeds efficiently. Is preferred. Generally, heating at about 120 to 180 ° C. may be performed, 130 to 170 ° C. is more preferable, and 140 to 160 ° C. is more preferable, but the required birefringence (retardation) and the optically anisotropic layer to be used The suitable temperature differs depending on the thermosetting reactivity. The heat treatment time is not particularly limited, but is preferably 1 minute to 5 hours, more preferably 3 minutes to 3 hours, and particularly preferably 5 minutes to 2 hours.

The reaction treatment can be performed by whole surface exposure instead of the whole surface heat treatment. In this case, the irradiation wavelength of the light source preferably has a peak at 250 to 450 nm, and more preferably has a peak at 300 to 410 nm. In the case where a step is simultaneously formed by the photosensitive resin layer, it is also preferable to irradiate light in a wavelength region that can cure the resin layer (eg, 365 nm, 405 nm, etc.). Specifically, an ultrahigh pressure mercury lamp, a high pressure mercury lamp, a metal halide lamp, a blue laser, and the like can be given. Usually 3~2000mJ / cm ² about the preferred amount of exposure, and more preferably 5~1000mJ / cm ² or so, more preferably 10 to 500 mJ / cm ² or so, and most preferably at about 10 to 300 mJ / cm ² .

[Finish heat treatment]
If you want to further improve the stability of the birefringence pattern produced in the previous steps, increase the durability by further reacting the unreacted reactive groups still remaining after immobilization. Finishing heat treatment may be performed for the purpose of removing unnecessary components by vaporizing or burning them. This is particularly effective when a birefringence pattern is produced by pattern exposure and heating overall exposure, or pattern-like heat treatment and overall exposure. The finishing heat treatment may be performed at a temperature of about 180 to 300 ° C, more preferably 190 to 260 ° C, and even more preferably 200 to 240 ° C. The heat treatment time is not particularly limited, but is preferably 1 minute to 5 hours, more preferably 3 minutes to 3 hours, and particularly preferably 5 minutes to 2 hours.

[Birefringence pattern]
The birefringence pattern obtained by exposing and baking the birefringence pattern builder as described above is usually almost colorless and transparent, and when there is a reflective layer, it may only show its color, When sandwiched between polarizing plates, or sandwiched between a reflective layer and a polarizing plate, it shows a characteristic brightness or darkness or color and can be easily recognized visually. Taking advantage of this property, the birefringence pattern obtained by the above manufacturing method can be used, for example, as a forgery prevention means. That is, while the birefringence pattern is usually almost invisible by visual observation, a multicolor image can be easily identified through the polarizing plate. When the birefringence pattern is copied without passing through the polarizing plate, nothing is reflected. Conversely, when the birefringence pattern is copied through the polarizing plate, it remains as a permanent pattern, that is, a visible pattern without the polarizing plate. Therefore, it is difficult to duplicate a birefringence pattern. Since a method for producing such a birefringence pattern is not widespread and the material is also special, it is considered suitable for use as a forgery prevention means.

[Functional layer laminated on birefringence pattern]
The birefringence pattern builder may be further laminated with functional layers having various functions after the birefringence pattern is produced as described above. Although it does not specifically limit as a functional layer, For example, the hard-coat layer which prevents the damage | wound of a surface, the reflection layer which makes easy the visual recognition of a birefringence pattern etc. are mention | raise | lifted. In order to facilitate identification, it is particularly preferable to have a reflective layer under the birefringence pattern.

[Method for producing laminated structure having birefringence pattern]
The laminated structure of the present invention can be formed by providing an optical stress sensitive layer for visualizing that the layer has been peeled off on the birefringence pattern produced as described above. The laminated structure of the present invention may further have an adhesive layer for attaching to an article, if necessary. The optical stress sensitive layer may also serve as the adhesive layer.

[Adhesive layer]
The material for forming the adhesive layer is not limited to the above, and is not particularly limited as long as it does not alter or affect the aluminum foil. For example, butyl rubber-based, natural rubber-based, silicone-based, polyisobutyl-based adhesive components, alkyl methacrylate, vinyl ester, acrylonitrile, styrene, vinyl monomer and other aggregate components, unsaturated carboxylic acid, hydroxyl group-containing monomer, A pressure-sensitive adhesive layer to which additives such as a modifying component typified by acrylonitrile and the like, a polymerization initiator, a plasticizer, a curing agent, a curing accelerator, and an antioxidant are added as necessary can be formed. Specifically, emulsions made by adding microspheres to the adhesive (B-7589 made by Nippon Carbide Co., Ltd.) or those containing a curing agent added to the adhesive (such as 2-ethylhexyl acrylate) are emulsified. Etc.) can be used.
In addition, what is necessary is just to use the composition similar to the composition which forms said adhesive layer as an adhesive agent when sticking the laminated structure of this invention which does not have an adhesive layer to articles | goods. A commercially available adhesive may be appropriately selected and used.

[Patterned adhesive layer]
The adhesive layer may be a patterned adhesive layer having regions with different adhesive strengths, and may be an optical stress sensitive layer. By providing a patterned adhesive layer, it is possible to form a brittle laminated structure in which the birefringence pattern changes due to peeling or the birefringence pattern is ruptured by peeling. The patterned adhesive layer may be formed by selecting two or more different adhesive strengths from the adhesive layer forming composition formed as described above. The adhesive strength of the composition can be adjusted by the adhesive component or the concentration of the adhesive component. The maximum adhesive strength in the patterned adhesive layer is preferably stronger than the force for breaking the reflective layer, and the minimum adhesive strength is preferably weaker than the force for breaking the reflective layer.

The patterned adhesive layer may also serve as a layer that exhibits optical anisotropy by stress.
When the patterned adhesive layer is treated with the selected release agent, the laminated structure may be peeled off without any effect of peeling detection such as breakage of the reflective layer. Therefore, when a release agent having a release action can be predicted for the composition for forming an adhesive layer selected for creating a patterned adhesive layer, by touching a component such as an organic solvent contained in the release agent, It is also preferable to add a layer that swells to change birefringence, swells, or causes whitening / yellowing to the laminated structure.

[Peeling layer]
The adhesive layer and the release layer can be combined to form an optical stress sensitive layer that gives regions having different adhesive strengths. That is, by providing a pattern-like release layer on the adhesive layer and making the release layer forming part and the release layer non-forming part exist on the adhesive layer, a difference in adhesive strength is provided, resulting in a latent image with a birefringence pattern. Distortion can also occur.
The release layer may be provided on either the birefringence pattern side or the side on which the laminated structure is adhered to the article as viewed from the adhesive layer, but is preferably provided on the birefringence pattern side. The release layer and the adhesive layer are preferably in contact with each other.
Materials for forming the release layer include aluminum foil and poorly adhesive acrylic resin, chlorinated rubber resin, vinyl chloride-vinyl acetate copolymer resin, cellulose resin, chlorinated propylene resin, silicone resin, and other resins. Examples thereof include a resin mixed with silicon oil, fatty acid amide and zinc stearate, or a fragile resin mixed with a large amount of an inorganic filler.

  The birefringence pattern builder used as a transfer material may have a release layer (not in a pattern) on the temporary support. The release layer controls the adhesion between the temporary support and the release layer, or between the release layer and the layer immediately above the release layer, and serves to assist the release of the temporary support after transferring the optically anisotropic layer. In addition, the other functional layers described above, such as an alignment layer and a mechanical property control layer, may have a function as a release layer.

[Layer expressing optical anisotropy by stress]
Examples of the layer that exhibits optical anisotropy by stress include, for example, a layer that exhibits birefringence by stress such as stretching or photoelasticity caused by a pulling operation at the time of peeling, and a layer in which birefringence that remains after peeling remains. The layer shape etc. which change the optical path at the time of visual recognition by deform | transforming a layer shape by these are mentioned.
There are no particular limitations on the material and method for producing a layer that exhibits optical anisotropy due to stress. The position where a layer that exhibits optical anisotropy due to stress is provided can exhibit optical anisotropy under stress due to peeling, and affect the latent image provided by the birefringence pattern after peeling. Although it will not specifically limit if it is a position which can do, It is preferable that it exists in the vicinity of the patterned optically anisotropic layer, especially the position adjacent to the patterned optically anisotropic layer. Moreover, the arrangement | positioning by the side of a support body which receives a bigger stress by peeling operation | movement rather than arrangement | positioning by the side of visual recognition is preferable.

What is necessary is just to provide the layer which expresses optical anisotropy by stress on the birefringence pattern produced as mentioned above. A reflective layer or a support having a reflective function, and an adhesive layer can be further provided on the layer that exhibits optical anisotropy by the provided stress, if necessary.
As shown in FIGS. 1 (h), 1 (i), and 2 (g), the layer that develops optical anisotropy due to stress is a position adjacent to the optical anisotropic layer in the birefringence pattern forming material. It is also preferable to be provided. This is because it can be easily provided at a position adjacent to the patterned optically anisotropic layer. However, in this case, it is necessary that the property of developing optical anisotropy due to stress does not disappear due to the processing in the manufacturing process of the patterned optically anisotropic layer.

[Surface protective layer]
A thin surface protective layer (protective film) is preferably provided on a resin layer such as an adhesive layer in order to protect it from contamination and damage during storage. The property of the surface protective layer is not particularly limited and may be made of the same or similar material as that of the temporary support, but it should be easily separated from an adjacent layer (for example, an adhesive layer). As a material for the surface protective layer, for example, PET (polyethylene terephthalate), silicon paper, polyolefin or polytetrafluoroethylene sheet is suitable.

[Article to which the laminated structure is adhered]
The article to which the laminated structure is adhered is not particularly limited, and examples thereof include an ink jet cartridge.
A laminated structure having a reflective layer is preferable because it can adhere to many articles and a latent image can be visualized with a single polarizing plate.
The laminated structure produced in a form having no reflective layer can be used by sticking to a transparent article. The birefringence pattern in a laminated structure produced without a reflective layer is such that the latent image can be visualized with the laminated structure placed between two polarizing plates stacked so that the absorption axes are substantially orthogonal to each other. It is preferable that it is designed.

  The present invention will be described more specifically with reference to the following examples. The materials, reagents, amounts and ratios of substances, operations, and the like shown in the following examples can be appropriately changed without departing from the gist of the present invention. Therefore, the scope of the present invention is not limited to the following specific examples.

(Preparation of coating liquid CU-1 for mechanical property control layer (thermoplastic resin layer))
The following composition was prepared, filtered through a polypropylene filter having a pore diameter of 30 μm, and used as a coating liquid CU-1 for a thermoplastic resin layer.
────────────────────────────────── ――――――
Coating composition for mechanical property control layer (mass%)
────────────────────────────────── ――――――
Methyl methacrylate / 2-ethylhexyl acrylate / benzyl methacrylate / methacrylic acid copolymer (copolymerization composition ratio (molar ratio) = 55/30/10/5, weight average molecular weight = 100,000, Tg≈70 ° C.)
5.89
Styrene / acrylic acid copolymer (copolymerization composition ratio (molar ratio) = 65/35, weight average molecular weight = 10,000, Tg≈100 ° C.)
13.74
BPE-500 (manufactured by Shin-Nakamura Chemical Co., Ltd.) 9.20
Megafuck F-780-F (manufactured by Dainippon Ink & Chemicals, Inc.) 0.55
Methanol 11.22
Propylene glycol monomethyl ether acetate 6.43
Methyl ethyl ketone 52.97
────────────────────────────────── ――――――

(Preparation of coating liquid AL-1 for alignment layer)
The following composition was prepared, filtered through a polypropylene filter having a pore size of 30 μm, and used as the intermediate layer / alignment layer coating solution AL-1.
──────────────────────────────────――
Coating solution composition for intermediate layer / alignment layer (% by mass)
──────────────────────────────────――
Polyvinyl alcohol (PVA205, manufactured by Kuraray Co., Ltd.) 3.21
Polyvinylpyrrolidone (Luvitec K30, manufactured by BASF) 1.48
Distilled water 52.1
Methanol 43.21
──────────────────────────────────――

(Preparation of coating liquid LC-1 for optically anisotropic layer)
After the following composition was prepared, it was filtered through a polypropylene filter having a pore size of 0.2 μm and used as a coating liquid LC-1 for an optically anisotropic layer.
LC-1-1 was synthesized based on the method described in JP-A No. 2004-123882. LC-1-1 is a liquid crystal compound having two reactive groups. One of the two reactive groups is an acrylic group which is a radical reactive group, and the other is an oxetane group which is a cationic reactive group. is there.
LC-1-2 is Tetrahedron Lett. It was synthesized according to the method described in Journal, Vol. 43, page 6793 (2002).

────────────────────────────────── ――――――
Coating liquid composition for optically anisotropic layer (% by mass)
────────────────────────────────── ――――――
Rod-shaped liquid crystal (LC-1-1) 19.57
Horizontal alignment agent (LC-1-2) 0.01
Cationic photopolymerization initiator (Cyracure UVI 6974, manufactured by Dow Chemical) 0.40
Polymerization control agent (IRGANOX1076, manufactured by Ciba Specialty Chemicals Co., Ltd.) 0.02
Methyl ethyl ketone 80.0
─────────────────────────────────────――

(Preparation of birefringence pattern transfer material TR-1)
On the temporary support of a 100 μm-thick easy-adhesive polyethylene terephthalate film (Cosmo Shine A4100, manufactured by Toyobo Co., Ltd.), in order using a wire bar, the coating liquid CU-1 for the mechanical property control layer, for the alignment layer The coating liquid AL-1 was applied and dried. The dry film thicknesses were 14.6 μm and 1.6 μm, respectively. Next, the coating liquid LC-1 for optically anisotropic layer was applied using a wire bar, dried at a film surface temperature of 105 ° C. for 2 minutes to form a liquid crystal phase, and then an air-cooled metal halide lamp of 160 W / cm in air. The optically anisotropic layer having a thickness of 2.4 μm was formed by fixing the alignment state by irradiating with ultraviolet rays (made by Eye Graphics Co., Ltd.). The illuminance of ultraviolet rays used at this time was 50 mW / cm ² in the UV-B region (integration of wavelengths 280 nm to 320 nm), and the irradiation amount was 35 mJ / cm ² in the UV-B region.

On the optically anisotropic layer formed above, the transfer adhesive layer coating solution AD-1 is applied and dried to form a 1.0 μm transfer adhesive layer, and then a protective film (polypropylene film having a thickness of 12 μm) is pressure-bonded. Then, a birefringence pattern transfer material TR-1 was prepared.
(Preparation of birefringence pattern transfer material TR-6)
A transfer material TR-6 for preparing a birefringence pattern was prepared in the same manner as TR-1, except that the thickness of the optically anisotropic layer was 1.2 μm.

(Preparation of birefringence pattern BP-9 having a reflective layer)
A substrate in which an aluminum foil was temporarily fixed to glass with a heat-resistant tape was produced, and this substrate was heated at 100 ° C. for 2 minutes with a substrate preheating device.
After peeling off the protective film of the birefringence pattern transfer material TR-1, a substrate heated at 100 ° C. for 2 minutes using a laminator (manufactured by Hitachi Industries, Ltd. (Lamic II type)) is heated to a rubber roller temperature of 130. Lamination was performed at a temperature of 100 ° C., a linear pressure of 100 N / cm, and a conveyance speed of 1.4 m / min.
After lamination, the substrate after peeling the temporary support was subjected to pattern exposure at an exposure amount of 50 mJ / cm ² using Mikasa M-3L mask aligner and photomask IV (FIG. 7).

The birefringence pattern preparation transfer material TR-6 was again laminated on the exposed substrate by the same method. At this time, attention was paid so that the slow axis directions of both the optically anisotropic layer laminated earlier and the optically anisotropic layer laminated later substantially coincided.
After lamination, the substrate after peeling the temporary support was subjected to pattern exposure using an M-3L mask aligner manufactured by Mikasa and a photomask V (FIG. 8) at an exposure amount of 50 mJ / cm ² . Further, after baking for 1 hour in a clean oven at 230 ° C., the aluminum foil on which the birefringence pattern was laminated was removed from the glass plate to produce a multicolor birefringence pattern BP-9 on the reflective layer of the present invention. The enlarged view of the pattern observed through a polarizing plate on BP-9 is shown in FIG. In the figure, while the ground aluminum foil is silver, a two-color pattern is observed in which the lattice portion is dark blue and the shaded portion is yellow or orange.

[Example 1]
Two types of adhesives having different adhesive forces were applied in a pattern on the aluminum foil side of the birefringence pattern obtained above, and a PET film was provided as a protective film on the coated surface for storage. The protective film of the produced seal was peeled off and adhered to the pattern paper. Adhesive with strong adhesive strength when trying to peel aluminum foil as a clue, Adhesive with weak adhesive strength, part of the birefringence pattern layer remains on the application part of Coponel 5411 made by Nippon Synthetic Chemical Industry Only the coated part of Coponil N-3495HS manufactured by Synthetic Chemical Industry Co., Ltd. was peeled off and the birefringence pattern was broken.

[Example 2]
On the aluminum foil side of the birefringence pattern obtained above, the composition for forming a release layer having the composition described above was applied so as to partially cover, and dried at 110 ° C. to form a brittle release layer.
───────────────────────────────────
Release layer forming composition (mass%)
───────────────────────────────────
Acrylic resin (PMMA: Methyl methacrylate resin)
25
Toluene 30
Methyl ethyl ketone 30
Methyl isobutyl ketone 15
───────────────────────────────────

On the aluminum foil on which the release layer was formed, an adhesive layer having the following composition was applied and dried at 110 ° C. to form an adhesive layer.
───────────────────────────────────
(Adhesive layer forming composition) (% by mass)
───────────────────────────────────
Acrylic adhesive (COPONIL NS-004, manufactured by Nippon Synthetic Chemical Industry Co., Ltd.)
24
Methyl ethyl ketone 38
Toluene 38
───────────────────────────────────

Further, a PET film was provided as a protective film on the adhesive layer and stored.
Peel off the produced PET film of the sticker and attach it to the paper pattern so that the adhesive layer is the surface of the paper pattern. Only the part to which the release layer was applied was peeled off and the birefringence pattern was broken.

It is a schematic sectional drawing which shows the example of a birefringence pattern preparation material. It is a schematic sectional drawing of the example of the birefringence pattern preparation material used as a transfer material It is a schematic sectional drawing of the example of a birefringence pattern. It is the figure which showed typically the schematic sectional drawing of the example (example using a patterned adhesion layer) of the laminated structure of this invention, and the state by which this laminated structure is peeled off. It is the figure which showed typically the state from which this laminated structure used as a schematic sectional drawing and a seal | sticker of the example (example using a peeling layer and the adhesion layer) of the laminated structure of this invention was peeled off. Schematic sectional view of an example of a laminated structure of the present invention (an example using a layer that develops optical anisotropy by stress) and a diagram schematically showing a state in which the laminated structure is peeled off, used as a seal It is. It is a figure which shows the shape of the photomask IV used in the Example. The white part is the exposed part and the black part is the unexposed part. It is a figure which shows the shape of the photomask V used in the Example. The white part is the exposed part and the black part is the unexposed part. It is an enlarged view of the pattern observed when the birefringence pattern produced in the Example is observed through a polarizing plate.

Explanation of symbols

5 Birefringence Pattern 6 Patterned Adhesive Layer 7 Peeling Layer 8 Adhesive Layer 9 Optical Stress-Sensitive Layer 10 Layer 10 ′ Expressing Optical Anisotropy by Stress 10 Layer 11 Expressing Optical Anisotropy by Stress Substrate 12 Optically anisotropic layer 12A Optically anisotropic layer exposed portion 12B Optically anisotropic layer unexposed portion 12F First optically anisotropic layer 12S Second optically anisotropic layer 13 Orientation layer (on support)
14 Transfer Adhesive Layer 14F First Transfer Adhesive Layer 14S Second Transfer Adhesive Layer 14T Third Transfer Adhesive Layer 18 Surface Protective Layer 21 Temporary Support 22 Orientation Layer (On Temporary Support)
22F First orientation layer on temporary support 22S First orientation layer on temporary support 23 Mechanical property control layer 112 Patterned optical anisotropic layer 112-A Patterned optical anisotropic layer (exposed part)
112-B Patterned optically anisotropic layer (unexposed part)
112F-A Patterned first optically anisotropic layer (exposed part)
112F-B Patterned first optically anisotropic layer (unexposed part)
112S-A Patterned second optically anisotropic layer (exposed part)
112S-B Patterned second optically anisotropic layer (unexposed part)
112T-A Patterned third optically anisotropic layer (exposed part)
112T-B Patterned third optically anisotropic layer (unexposed part)
35 Reflective layer

Claims (9)

A laminated structure including an optical stress-sensitive layer and a patterned optically anisotropic layer having regions having different birefringence in a pattern. The laminated structure according to claim 1, comprising a reflective layer. The laminated structure according to claim 1 or 2, wherein the regions having different birefringence are regions having different retardations. The laminated structure according to any one of claims 1 to 3, wherein the patterned optically anisotropic layer is produced by a method including the following steps in this order:
(1) preparing a birefringence pattern builder including an optically anisotropic layer containing a polymer having a reactive group;
(2) A step of subjecting the birefringence pattern builder to pattern heat treatment or pattern ionizing radiation irradiation;
(3) A step of reacting or deactivating the remaining reactive groups in the optically anisotropic layer. The laminated structure according to claim 1, wherein the optical stress-sensitive layer is a layer that exhibits optical anisotropy by stress. The laminated structure as described in any one of Claims 1-5 which has an adhesion layer. The laminated structure according to any one of claims 1 to 4, wherein the optical stress sensitive layer is a patterned adhesive layer having a plurality of regions having different adhesive strengths. The laminated structure according to any one of claims 1 to 4, wherein the optical stress sensitive layer includes an adhesive layer and a patterned release layer. The laminated structure according to any one of claims 6 to 8, which is used as a forgery prevention seal.

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