JP7399655B2 - Method for manufacturing optical laminates - Google Patents

Description

The present invention relates to a method for manufacturing an optical laminate.

Display devices such as organic EL display devices and liquid crystal display devices use members containing optically anisotropic films such as polarizing films and retardation films. As such an optically anisotropic film, one in which a layer of a liquid crystal compound is formed on a base film is known. Patent Document 1 describes the use of a liquid crystal material in a retardation layer of an optical film used in a circularly polarizing plate or the like.

JP2014-222282A

An object of the present invention is to provide a method for manufacturing an optical laminate suitable for manufacturing an optical laminate having a liquid crystal layer.

The present invention provides the following method for manufacturing an optical laminate.
[1] A method for producing an optical laminate including a first optical functional layer, an adhesive layer, and a second optical functional layer in this order,
The adhesive layer is an adhesive cured layer in which an adhesive is cured,
At least one of the first optical functional layer and the second optical functional layer includes a liquid crystal layer formed by polymerizing a polymerizable liquid crystal compound on a base layer,
The first optical functional layer and the second optical functional layer each have an adhesive surface on the adhesive layer side,
Only one of the adhesive surfaces is an exposed surface exposed by peeling off the base layer,
providing an adhesive composition layer for forming the adhesive layer on the other adhesive surface of the adhesive surfaces by applying the adhesive;
A method for manufacturing an optical laminate, comprising the step of laminating the first optical functional layer and the second optical functional layer via the adhesive composition layer.

[2] The first optical functional layer includes a first liquid crystal layer formed by polymerizing a polymerizable liquid crystal compound on the first base layer,
The one adhesive surface is an exposed surface exposed by peeling off the first base layer,
The second optical functional layer includes a second liquid crystal layer formed by polymerizing a polymerizable liquid crystal compound on the second base layer,
The method for manufacturing an optical laminate according to [1], wherein the other adhesive surface is a surface of the second liquid crystal layer opposite to the second base layer.

[3] The second optical functional layer is a second liquid crystal layer with a base material layer having the second liquid crystal layer and the second base layer,
The method for producing an optical laminate according to [2], which includes a step of peeling off the second base layer after the laminating step.

[4] The optical system according to [2] or [3], wherein the first optical functional layer includes, in this order, a polarizing functional layer including at least a linear polarizing layer, an adhesive layer for the polarizing functional layer, and the first liquid crystal layer. Method for manufacturing a laminate.

[5] Further, a first base material layer-attached substrate having the polarizing functional layer, the adhesive layer for the polarizing functional layer, the first liquid crystal layer, and the first base material layer in order from the adhesive layer side for the polarizing functional layer. and a liquid crystal layer in this order, the step of preparing a liquid crystal layer with a polarization function layer,
The method for manufacturing an optical laminate according to [4], wherein the one adhesive surface is an exposed surface exposed by peeling off the first base layer from the polarizing functional layer-attached liquid crystal layer.

[6] The method for producing an optical laminate according to [4] or [5], wherein the adhesive layer for polarizing functional layer is an adhesive layer.

[7] The first optical functional layer includes a first liquid crystal layer formed by polymerizing a polymerizable liquid crystal compound on the first base layer,
The one adhesive surface is an exposed surface exposed by peeling off the first base layer,
The method for producing an optical laminate according to [1], wherein the second optical functional layer is a polarizing functional layer containing at least a linearly polarizing layer.

[8] The method for manufacturing an optical laminate according to [7], wherein the first optical functional layer includes the first liquid crystal layer, an adhesive layer for a liquid crystal layer, and a second liquid crystal layer in this order.

[9] Further, it has the first base material layer, the first liquid crystal layer, the adhesive layer for the liquid crystal layer, and the second liquid crystal layer and the second base material layer in order from the adhesive layer for the liquid crystal layer side. a step of preparing a liquid crystal layer laminate with a base material layer having a second liquid crystal layer with a base material layer in this order,
The method for manufacturing an optical laminate according to [8], wherein the one adhesive surface is an exposed surface exposed by peeling off the first base layer from the base layer-attached liquid crystal layer laminate.

[10] The method for producing an optical laminate according to [9], which includes a step of peeling off the second base layer after the laminating step.

[11] The method for producing an optical laminate according to [9] or [10], wherein the adhesive layer for a liquid crystal layer is an adhesive layer.

[12] The optical laminate is a circularly polarizing plate,
The first liquid crystal layer and the second liquid crystal layer have the following [a] or [b]:
[a] The first liquid crystal layer is a half-wave plate, and the second liquid crystal layer is a quarter-wave plate;
[b] One of the first liquid crystal layer and the second liquid crystal layer is a reverse wavelength dispersion quarter-wave plate, and the other is a positive C plate;
The method for producing an optical laminate according to any one of [4] to [6] and [8] to [11], which satisfies the following relationship.

[13] Further, a step of preparing a first liquid crystal layer with a base material layer having the first base material layer and the first liquid crystal layer;
The method for producing an optical laminate according to any one of [2] to [12], comprising the step of peeling off the first base layer.

[14] The method for producing an optical laminate according to [13], wherein the optical laminate includes an alignment layer on the first base layer side of the first liquid crystal layer.

According to the present invention, it is possible to provide a method for manufacturing an optical laminate suitable for manufacturing an optical laminate having a liquid crystal layer.

(a) to (d) are schematic cross-sectional views schematically showing an example of the manufacturing process of the optical laminate of the present invention. (a) to (d) are schematic cross-sectional views schematically showing a continuation of the manufacturing process of the optical laminate shown in FIG. 1. (a) to (c) are schematic cross-sectional views schematically showing a continuation of the manufacturing process of the optical laminate shown in FIG. 2. (a) to (d) are schematic cross-sectional views schematically showing other examples of the manufacturing process of the optical laminate of the present invention. (a) to (d) are schematic cross-sectional views schematically showing a continuation of the manufacturing process of the optical laminate shown in FIG. 4.

Hereinafter, preferred embodiments of the method for manufacturing an optical laminate of the present invention will be described with reference to the drawings. In addition, each embodiment and its modification shown below may be combined arbitrarily. Further, in each embodiment and its modification, the same members as those described in the previous embodiment or its modification are given the same reference numerals, and the description thereof will be omitted.

[Embodiment 1]
1 to 3 are schematic cross-sectional views schematically showing an example (Embodiment 1) of the manufacturing process of the optical laminate of the present invention. In the figure, W represents the width direction. As shown in FIG. 3(b), the optical laminate 52 obtained by the manufacturing method of the present invention includes a polarizing plate 60 in which a protective layer is formed on at least one surface of a polarizing layer (linear polarizing layer, polarizing functional layer). (polarizing functional layer), polarizing plate adhesive layer 36 (polarizing functional layer adhesive layer), first liquid crystal layer 12, liquid crystal layer adhesive layer 30 (adhesive layer), and second liquid crystal layer 22 in this order. The optical laminate 52 is preferably a circularly polarizing plate, and in this case, the first liquid crystal layer 12 and the second liquid crystal layer 22 have the following [a] or [b]:
[a] The first liquid crystal layer 12 is a half-wave plate, and the second liquid crystal layer 22 is a quarter-wave plate.
[b] One of the first liquid crystal layer 12 and the second liquid crystal layer 22 is a quarter-wave plate with reverse wavelength dispersion, and the other is a positive C plate;
It is preferable that the following relationship is satisfied. In the above [b], it is preferable that the first liquid crystal layer 12 is a quarter-wave plate with reverse wavelength dispersion, and the second liquid crystal layer 22 is a positive C plate.

The adhesive layer 30 for the liquid crystal layer of the optical laminate 52 is made by applying an adhesive to the second liquid crystal layer 22 side of the second liquid crystal layer 20 with a base material layer, and curing the applied adhesive, as described later. This is a hardened layer. In this specification, "adhesive" is used separately from "adhesive". In this specification, the term adhesive refers to an agent that joins and integrates two members by solidifying through a chemical reaction or the like, and its state changes before and after joining. In this specification, this solidified adhesive is referred to as an adhesive cured layer. In this specification, an adhesive refers to an agent that joins two members together due to its high viscosity without undergoing a solidification process, and does not change its state before and after joining. In this specification, a layer formed of this adhesive is referred to as an adhesive layer.

The optical laminate obtained by the manufacturing method of the present invention has a second base material on the opposite side of the second liquid crystal layer 22 from the adhesive layer 30 for the liquid crystal layer, as shown in FIG. 2(d) and FIG. 3(c). It may include the layer 21 and the adhesive composition layer 35 for optical elements. The polarizing layer included in the polarizing plate 60 may be a cured film (liquid crystal layer) in which a dichroic dye is oriented on a polymerizable liquid crystal compound, but it may be a cured film (liquid crystal layer) in which a dichroic dye is oriented in a polyvinyl alcohol resin film. It may also be a film. Details of the polarizing layer will be described later.

In the method for manufacturing the optical laminate 52 shown in FIG. 3(b), first, a polarizing plate adhesive composition layer 36a for forming a polarizing plate adhesive layer 36 on one surface of a polarizing plate 60 is prepared. A step of preparing a polarizing plate 61 with a material layer (FIG. 1(a)), and a step of preparing a polarizing plate 61 with a material layer, and a step of preparing a polarizing plate 61 with a material layer, and a step of preparing a polarizing plate 61 with a material layer, in which a first liquid crystal layer 12 (liquid crystal layer) is formed on a first base material layer 11 (base material layer). A step of preparing the first liquid crystal layer 10 (FIG. 1(b)) is performed.

When the polarizing plate adhesive layer 36 of the optical laminate 52 is an adhesive cured layer, the step of preparing the polarizing plate 61 with a composition layer includes a step of applying an adhesive to one surface of the polarizing plate 60. It may also include a step of drying the applied adhesive, if necessary. Further, the step of preparing the polarizing plate 61 with a composition layer is a step of applying an adhesive to one surface of the polarizing plate 60 when the polarizing plate adhesive layer 36 of the optical laminate 52 is an adhesive layer. Alternatively, the adhesive layer may be formed on the release-treated surface of the release film, and the adhesive layer of the release film may be coated with a polarizing plate. 60 may be included. In this embodiment, the surface of the polarizing plate 60 on which the polarizing plate adhesive composition layer 36a is provided is the exposed surface exposed by peeling off the base layer after polymerizing the polymerizable liquid crystal compound on the base layer. shall not be.

The step of preparing the first liquid crystal layer 10 with a base material layer includes the first base material layer 11 and the first liquid crystal layer 12 obtained by polymerizing a polymerizable liquid crystal compound on the first base material layer 11. It is only necessary to prepare the first liquid crystal layer 10 with a base material layer, and it may include a step of polymerizing a polymerizable liquid crystal compound on the first base material layer 11 to form the first liquid crystal layer 12. When polymerizing the polymerizable liquid crystal compound on the first base layer 11, a composition for forming a liquid crystal layer containing the polymerizable liquid crystal compound is applied onto the first base layer 11 and dried, and then the polymerizable liquid crystal compound is The first liquid crystal layer 12 may be formed by polymerizing a liquid crystal compound. The composition for forming a liquid crystal layer may contain, in addition to the polymerizable liquid crystal compound, a solvent, a polymerization initiator, a reactive additive, a leveling agent, a polymerization inhibitor, and the like.

Next, a first liquid crystal layer with a polarizing plate 41 (liquid crystal layer with a polarizing function layer) is prepared. The first liquid crystal layer with a polarizing plate 41 is formed by bonding the adhesive composition layer for polarizing plate 36a of the polarizing plate with a composition layer 61 and the first liquid crystal layer 12 side of the first liquid crystal layer with a base material layer 10. (FIG. 1(c)), and further, an adhesive layer 36 for a polarizing plate can be formed from the adhesive composition layer 36a for a polarizing plate (FIG. 1(d)). The method for forming the polarizing plate adhesive layer 36 from the polarizing plate adhesive composition layer 36a may be selected depending on the components contained in the polarizing plate adhesive composition layer 36a. The layer 36a may be cured, or if the component does not require curing, the polarizing plate adhesive composition layer 36a may be used as the polarizing plate adhesive layer 36 without any special treatment. The first polarizing plate-equipped liquid crystal layer 41 includes a polarizing plate 60, a polarizing plate adhesive layer 36, a first liquid crystal layer 12, and a first base layer 11 in this order, as shown in FIG. 1(d).

Thereafter, by peeling off the first base layer 11 from the first polarizing plate-equipped liquid crystal layer 41, a second polarizing plate including the polarizing plate 60, the polarizing plate adhesive layer 36, and the first liquid crystal layer 12 in this order is obtained. A liquid crystal layer 42 (first optical functional layer) is obtained (FIG. 2(a)).

Next, a step of preparing a second liquid crystal layer 20 with a base material layer (second optical functional layer) in which a second liquid crystal layer 22 (liquid crystal layer) is formed on the second base material layer 21 (base material layer) is performed. (Figure 2(b)). The step of preparing the second liquid crystal layer 20 with a base material layer is similar to the step of preparing the first liquid crystal layer 10 with a base material layer, in which a polymerizable liquid crystal compound is polymerized on the second base material layer 21 to form a second It may include a step of forming the liquid crystal layer 22, in which a composition for forming a liquid crystal layer containing a polymerizable liquid crystal compound is applied onto the second base layer 21 and dried, and then the polymerizable liquid crystal compound is polymerized. The second liquid crystal layer 22 may be formed by using the same method.

Thereafter, an adhesive composition for a liquid crystal layer is used to form an adhesive layer 30 for a liquid crystal layer, which is an adhesive cured layer, on the second liquid crystal layer 22 side (the other adhesive surface) of the second liquid crystal layer 20 with a base material layer. A step of obtaining a liquid crystal layer 25 with a composition layer provided with the layer 30a (adhesive composition layer) is performed (FIG. 2(c)). The step of forming the adhesive composition layer 30a for a liquid crystal layer on the second liquid crystal layer 22 of the second liquid crystal layer 20 with a base material layer includes applying an adhesive to the second liquid crystal layer 22 side of the second liquid crystal layer 20 with a base material layer. The method may include a step of applying the adhesive and, if necessary, a step of drying the applied adhesive. As shown in FIG. 2(c), the composition-layered liquid crystal layer 25 includes a liquid crystal layer adhesive composition layer 30a, a second liquid crystal layer 22, and a second base material layer 21 in this order.

Next, the adhesive composition layer 30a for a liquid crystal layer of the liquid crystal layer 25 with a composition layer and the first liquid crystal layer 12 of the liquid crystal layer 42 with a second polarizing plate (first optical functional layer) shown in FIG. (FIG. 2(d)), forming an adhesive layer 30 for a liquid crystal layer from the adhesive composition layer 30a for a liquid crystal layer, and forming an optical fiber with a base material layer. A laminate 51 (optical laminate) is obtained (FIG. 3(a)). The method for forming the liquid crystal layer adhesive layer 30, which is an adhesive cured layer, from the liquid crystal layer adhesive composition layer 30a may be selected depending on the components contained in the liquid crystal layer adhesive composition layer 30a, for example, What is necessary is just to perform the process of curing the adhesive composition layer 30a for liquid crystal layer. As shown in FIG. 3A, the optical laminate 51 with a base material layer includes a polarizing plate 60, a polarizing plate adhesive layer 36, a first liquid crystal layer 12, a liquid crystal layer adhesive layer 30, a second liquid crystal layer 22, and the second base material layer 21 in this order.

The adhesive (adhesive composition) for forming the adhesive layer 30 for a liquid crystal layer, which is an adhesive cured layer, is especially suitable as long as it has fluidity to form the adhesive composition layer 30a for a liquid crystal layer by coating. Although not limited, a liquid adhesive having a suitable viscosity for application is preferred. Since the adhesive layer 30 for liquid crystal layer is used for an optical laminate, it is preferably transparent, and for example, a known adhesive used in the optical field can be used.

The adhesive can be formed, for example, by combining one or more of water-based adhesives, active energy ray-curable adhesives, pressure-sensitive adhesives, and the like. Examples of water-based adhesives include polyvinyl alcohol resin aqueous solutions, water-based two-component urethane emulsion adhesives, and the like. Active energy ray-curable adhesives are adhesives that are cured by irradiation with active energy rays such as ultraviolet rays, such as those containing a polymerizable compound and a photopolymerization initiator, those containing a photoreactive resin, Examples include those containing a binder resin and a photoreactive crosslinking agent. Examples of the polymerizable compound include photopolymerizable monomers such as photocurable epoxy monomers, photocurable acrylic monomers, and photocurable urethane monomers, and oligomers derived from these monomers. Examples of the photopolymerization initiator include those containing substances that generate active species such as neutral radicals, anion radicals, and cation radicals upon irradiation with active energy rays such as ultraviolet rays.

The adhesive layer 30 for the liquid crystal layer, which is an adhesive cured layer, is preferably formed using an active energy ray-curable adhesive, particularly an adhesive containing an ultraviolet curable epoxy monomer and a photocationic polymerization initiator. It is preferable to form using.

The surface to which the adhesive is applied, such as the second liquid crystal layer 22 side of the second liquid crystal layer 20 with a base material layer, may be subjected to surface treatment such as corona treatment, plasma treatment, flame treatment, etc. as necessary. good.

The adhesive coating device is not particularly limited, and for example, a known coating device used in the optical field can be used. Specific examples of coating devices include bar coaters, die coaters, comma coaters, gravure coaters, and the like. Among these, it is preferable to use a bar coater or a gravure coater in consideration of the uniformity of the thickness of the resulting adhesive cured layer.

The method for manufacturing the optical laminate 52 further includes a step of peeling off the second base layer 21 from the base layer-attached optical laminate 51 (FIG. 3(b)), and a step of peeling off the second base layer 21. A step of forming an optical element adhesive composition layer 35 on the exposed surface of the second base layer 21 side of the exposed second liquid crystal layer 22 to obtain an optical laminate 53 with an adhesive composition layer (optical laminate) ( 3(c)). As shown in FIG. 3C, the optical laminate 53 with an adhesive composition layer includes a polarizing plate 60, an adhesive layer for polarizing plate 36, a first liquid crystal layer 12, an adhesive layer for liquid crystal layer 30, and a second liquid crystal layer 22. , and an optical element adhesive composition layer 35 in this order.

The present inventors have proposed a liquid crystal layer formed by polymerizing a polymerizable liquid crystal compound on a base material layer, such as the first liquid crystal layer 10 with a base material layer and the second liquid crystal layer 20 with a base material layer described above. In the liquid crystal layer with a base material layer, the exposed surface exposed by peeling off the base material layer from the liquid crystal layer with a base material layer is compared to the opposite side (the side exposed to the atmosphere during polymerization of the polymerizable liquid crystal compound). It was also found that the adhesive composition is easily scratched by the coating device that applies the adhesive composition and the conveyor roll that conveys the liquid crystal layer with the base layer. Scratches that occur in the liquid crystal layer may cause problems such as deteriorating the appearance of the optical laminate or deteriorating the optical performance of the optical laminate.

Therefore, in the method for manufacturing the optical laminate 52, as shown in FIGS. 2(a) to 2(c), the second liquid crystal layer 20 with a base material layer and the liquid crystal layer 42 with a second polarizing plate are bonded together using adhesive for the liquid crystal layer. When laminating via the composition layer 30a, the liquid crystal layer adhesive composition layer 30a is formed on the second liquid crystal layer 22 side of the second liquid crystal layer 20 with a base material layer. In this way, the second liquid crystal layer 22 side of the second liquid crystal layer 20 with a base material layer and the first liquid crystal layer 12 side of the second liquid crystal layer 42 with a polarizing plate are connected to each other via the liquid crystal layer adhesive composition layer 30a. When laminating, the exposed surface exposed by peeling off the first base material layer 11 from the first liquid crystal layer 41 with a polarizing plate, and the second base material layer 21 of the second liquid crystal layer 20 with a base material layer. The adhesive composition layer 30a for liquid crystal layer is not formed on the exposed surface exposed by peeling off, and the liquid crystal layer 22 is not formed on the surface other than these exposed surfaces, which is the side opposite to the second base material layer 21 of the second liquid crystal layer 22. A layer adhesive composition layer 30a is formed. Therefore, in the method for manufacturing the optical laminate 52 described above, it is possible to suppress scratches on the first liquid crystal layer 12 and the second liquid crystal layer 22, thereby suppressing poor appearance and deterioration of optical performance of the optical laminate. It seems possible.

Furthermore, bonding by applying the adhesive used to form the liquid crystal layer adhesive layer 30, which is an adhesive cured layer, can be carried out using simple equipment, which is industrially advantageous. As described above, the exposed surface exposed by peeling off the base material layer from the liquid crystal layer with the base material layer is easily damaged by the coating device that applies adhesive, etc., but according to the manufacturing method of the present invention, the As the surface to which the agent is applied, a surface that is not the exposed surface exposed by peeling off the base material layer from the liquid crystal layer with the base material layer is selected. Therefore, even when an adhesive is used to form the adhesive layer 30 for a liquid crystal layer, it is considered that it is easy to suppress poor appearance and deterioration of optical performance of the optical laminate 52.

Furthermore, an adhesive layer formed using an adhesive generally has lower rigidity than an adhesive cured layer formed using an adhesive. Therefore, when the polarizing plate adhesive layer 36 is an adhesive layer, the liquid crystal layer adhesive composition layer 30a is formed on the first liquid crystal layer 12 side of the second polarizing plate attached liquid crystal layer 42 shown in FIG. 2(a). Then, it is estimated that the first liquid crystal layer 12 is more likely to be damaged than when the polarizing plate adhesive layer 36 is a cured adhesive layer. In the method for manufacturing the optical laminate 52 of this embodiment, even when the second liquid crystal layer 42 with a polarizing plate is a layer in which the first liquid crystal layer 12 and the polarizing plate 60 are laminated with an adhesive layer interposed therebetween, , since the liquid crystal layer adhesive composition layer 30a is formed on the second liquid crystal layer 22 side of the second liquid crystal layer 20 with a base material layer, the second liquid crystal layer 42 with a polarizing plate and the second liquid crystal layer with a base material layer It is considered that when laminating the layer 20, it is easy to prevent the first liquid crystal layer 12 and the second liquid crystal layer 22 from being scratched, and it is easy to prevent the optical laminate from having poor appearance or deteriorating its optical performance.

In addition, the polarizing plate 61 with a composition layer, the 1st liquid crystal layer 10 with a base material layer, the 2nd liquid crystal layer 20 with a base material layer, and the liquid crystal with a composition layer used for manufacturing an optical laminate in this embodiment The layer 25 and the film-like products such as laminates obtained using these are preferably long film-like products, and it is preferable to carry out each step while continuously transporting them. The width direction W is a direction perpendicular to the length direction of the film-like material.

The method for manufacturing an optical laminate according to this embodiment may be modified as shown in the following modification example. Furthermore, the embodiments described above and the modifications shown below may be combined arbitrarily.

(Modification 1 of Embodiment 1)
In the above, when obtaining the first liquid crystal layer 41 with a polarizing plate shown in FIG. 1(d), the polarizing plate 61 with a composition layer (FIG. Although the case where (a)) is used has been described as an example, the present invention is not limited to this. The adhesive composition layer for a polarizing plate may be formed on the first liquid crystal layer 12 side of the first liquid crystal layer 10 with a base material layer, and the adhesive composition layer for a polarizing plate 60 and the first liquid crystal layer of the first liquid crystal layer 12 with a base material layer may be formed on the first liquid crystal layer 12 side of the first liquid crystal layer 10 with a base material layer. It may be formed on both sides. Then, the first liquid crystal layer 12 side of the first liquid crystal layer 10 with a base material layer and the polarizing plate 60 are laminated via this adhesive composition layer for a polarizing plate, and the polarized light is emitted from the adhesive composition layer for a polarizing plate. What is necessary is to form an adhesive layer for the board.

In addition, in the first polarizing plate-equipped liquid crystal layer 41 (optical laminate), the surface of the polarizing plate 60 on the polarizing plate adhesive composition layer 36a side is bonded to the base material after the polymerizable liquid crystal compound is polymerized on the base material layer. In the case where the exposed surface is exposed by peeling off the layer, instead of providing the polarizing plate adhesive composition layer 36a on the polarizing plate 60 (first optical functional layer), the first liquid crystal layer 10 with a base material layer (first optical functional layer) is provided. An adhesive composition layer 36a for a polarizing plate is provided on the first liquid crystal layer 12 (optical functional layer 2). In this case, the first liquid crystal layer 41 with a polarizing plate or the second liquid crystal layer 42 with a polarizing plate can be the optical laminate of the present invention, and the polarizing plate 60 can be the first optical functional layer and the first liquid crystal layer with a base material layer. The liquid crystal layer 10 or the first liquid crystal layer 12 can serve as the second optical functional layer. Also in the case of this modification, after polymerizing the polymerizable liquid crystal compound on the base material layer, the adhesive composition layer 36a for a polarizing plate is not formed on the exposed surface exposed by peeling off the base material layer, and the exposed surface is An adhesive composition layer 36a for a polarizing plate is formed on the other surface. Therefore, it is thought that it is possible to suppress the first liquid crystal layer 12 from being scratched, thereby suppressing poor appearance and deterioration of optical performance of the optical laminate.

(Modification 2 of Embodiment 1)
In the above, the first liquid crystal layer with a base material layer 10 (FIG. 1(b)) in which the first liquid crystal layer 12 is formed on the first base material layer 11, and the second liquid crystal layer on the second base material layer 21 are described. Although the case where the second liquid crystal layer 20 with a base material layer (FIG. 2(b)) in which the layer 22 is formed is used has been described as an example, the present invention is not limited thereto. The first liquid crystal layer with a base material layer may have a first alignment layer between the first base material layer and the first liquid crystal layer, and the second liquid crystal layer with a base material layer may have a first alignment layer between the first base material layer and the first liquid crystal layer. A second alignment layer may be provided between the layer and the second liquid crystal layer.

When the first liquid crystal layer 10 with a base material layer has a first alignment layer, the optical laminate may or may not have the first alignment layer. When the optical laminate has a first alignment layer, when the first base layer is peeled off from the first liquid crystal layer 41 with a polarizing plate, the first alignment layer remains on the first liquid crystal layer 12. If the optical laminate does not have a first alignment layer, when the first base layer is peeled off from the first polarizing plate-attached liquid crystal layer 41, the adhesion strength of the first base layer and the first base layer may be adjusted. The adhesion between each layer may be adjusted so that one orientation layer can be peeled off. When the optical laminate has a first alignment layer, the first alignment layer is provided between the first liquid crystal layer 12 and the liquid crystal layer adhesive layer 30. The present inventors have discovered that when the exposed surface of the second polarizing plate-equipped liquid crystal layer formed by peeling off the first base material layer from the first polarizing plate-equipped liquid crystal layer is the first alignment layer, It has also been confirmed that the side of the first liquid crystal layer opposite to the first base layer is more easily scratched by the coating device that applies the adhesive composition and the conveyance roll. Therefore, even when the exposed surface of the liquid crystal layer with a second polarizing plate is the first alignment layer, the second base material of the second liquid crystal layer is not on the first alignment layer but on the surface other than the first alignment layer. By forming the adhesive composition layer for a liquid crystal layer on the opposite side of the layer, it is possible to suppress damage to the first liquid crystal layer and the first alignment layer.

When the second liquid crystal layer 20 with a base material layer has a second alignment layer, the optical laminate may or may not have the second alignment layer. When the optical laminate has a second alignment layer, the adhesion between each layer is adjusted such that the second alignment layer remains on the second liquid crystal layer when the second base layer is peeled off from the optical laminate with a base layer. If the optical laminate does not have a second alignment layer, when peeling the second base layer from the optical laminate with a base layer, the second alignment layer is peeled off together with the second base layer. The adhesion between each layer may be adjusted to achieve this. When the optical laminate includes a second alignment layer, the second alignment layer is provided on the side of the second liquid crystal layer opposite to the liquid crystal layer adhesive layer, and an optical element adhesive composition layer is provided on the second alignment layer. It is formed.

The adhesion between each layer can be adjusted by the components contained in each layer and the surface treatment performed on the surface of each layer. For example, the close contact between the alignment layer (first alignment layer or second alignment layer), base material layer (first base material layer or second base material layer) and liquid crystal layer (first liquid crystal layer or second liquid crystal layer) The force depends on the type and amount of additives such as polymerization initiators, reactive additives, leveling agents, and polymerization inhibitors contained in the alignment layer and liquid crystal layer, the surface of the substrate layer on the alignment layer side, and the amount on the substrate layer. It can be adjusted by surface treatment such as corona treatment, plasma treatment, flame treatment, etc. performed on the surface of the provided alignment layer.

[Embodiment 2]
4 to 5 are schematic cross-sectional views schematically showing an example (Embodiment 2) of the manufacturing process of the optical laminate of the present invention. In the figure, W represents the width direction. As shown in FIG. 5(c), the layer structure of the optical laminate 57 obtained by the manufacturing method of the present invention has a protective layer formed on at least one surface of the polarizing layer (linear polarizing layer, polarizing functional layer). Includes a polarizing plate 60 (polarizing functional layer), a polarizing plate adhesive layer 36 (adhesive layer, polarizing functional layer adhesive layer), a first liquid crystal layer 12, a liquid crystal layer adhesive layer 34, and a second liquid crystal layer 22 in this order. . The optical laminate 57 is preferably a circularly polarizing plate, and in this case, the first liquid crystal layer 12 and the second liquid crystal layer 22 have the following [a] or [b]:
[a] The first liquid crystal layer 12 is a half-wave plate, and the second liquid crystal layer 22 is a quarter-wave plate.
[b] One of the first liquid crystal layer 12 and the second liquid crystal layer 22 is a quarter-wave plate with reverse wavelength dispersion, and the other is a positive C plate;
It is preferable that the following relationship is satisfied. In the above [b], it is preferable that the first liquid crystal layer 12 is a quarter-wave plate with reverse wavelength dispersion, and the second liquid crystal layer 22 is a positive C plate.

The polarizing plate adhesive layer 36 of the optical laminate 57 is a cured adhesive layer in which an adhesive is applied to the polarizing plate 60 and the applied adhesive is cured, as will be described later. As shown in FIGS. 5(b) and 5(d), the optical laminate obtained by the manufacturing method of the present invention has a second base material layer 21 on the opposite side of the second liquid crystal layer 22 from the liquid crystal layer adhesive layer 34. It may also include an adhesive composition layer 35 for optical elements.

In the method for manufacturing an optical laminate shown in FIG. 5(c), a base material in which the first liquid crystal layer 12 (liquid crystal layer) is formed on the first base layer 11 (base material layer) described in the previous embodiment is used. The step of preparing the first layered liquid crystal layer 10 (FIG. 1(b)), the step of preparing the first liquid crystal layer 10 with a base material layer, in which the second liquid crystal layer 22 (liquid crystal layer) is formed on the second base material layer 21 (base material layer). 2. A step of preparing a second liquid crystal layer 20 (FIG. 2(b)), and a liquid crystal layer for forming a liquid crystal layer adhesive layer 34 on the second liquid crystal layer 22 side of the second liquid crystal layer 20 with a base material layer. A step (FIG. 4(a)) of obtaining a liquid crystal layer 26 with a composition layer provided with an adhesive composition layer 34a is performed. The step of preparing the first liquid crystal layer 10 with a base material layer may include the step of polymerizing a polymerizable liquid crystal compound on the first base layer 11 to form the first liquid crystal layer 12 . Similarly, the step of preparing the second liquid crystal layer 20 with a base layer may include the step of polymerizing a polymerizable liquid crystal compound on the second base layer 21 to form the second liquid crystal layer 22. .

When the liquid crystal layer adhesive layer 34 of the optical laminate 57 is an adhesive cured layer, the step of obtaining the liquid crystal layer 26 with a composition layer is performed on the second liquid crystal layer 22 side of the second liquid crystal layer 20 with a base material layer. The method may include a step of applying an adhesive to the substrate, and may also include a step of drying the applied adhesive, if necessary. Further, in the case where the liquid crystal layer adhesive layer 34 of the optical laminate 57 is an adhesive layer, the step of obtaining the liquid crystal layer 26 with a composition layer includes the step of obtaining the second liquid crystal layer 26 of the second liquid crystal layer 20 with a base material layer. It may include a step of applying an adhesive to the side and, if necessary, a step of drying the applied adhesive, or forming an adhesive layer on the release-treated surface of the release film and releasing the adhesive. It may include a step of transferring the adhesive layer of the film to the second liquid crystal layer 20 with a base material layer.

Subsequently, a liquid crystal layer laminate 46 with a base material layer is prepared. The liquid crystal layer laminate 46 with a base material layer has a base material such that the first liquid crystal layer 12 and the second liquid crystal layer 22 face each other via the adhesive composition layer 34a for liquid crystal layer of the liquid crystal layer 26 with a composition layer. It can be obtained by laminating the first layered liquid crystal layer 10 and the liquid crystal layer 26 with a composition layer (FIG. 4(b)), and forming the adhesive layer 34 for a liquid crystal layer from the adhesive composition layer 34a for a liquid crystal layer. (Figure 4(c)). As shown in FIG. 4C, the liquid crystal layer laminate 46 with a base material layer includes a first base material layer 11, a first liquid crystal layer 12, an adhesive layer for liquid crystal layer 34, a second liquid crystal layer 22, and a second liquid crystal layer. The base material layer 21 is included in this order.

Thereafter, by peeling off the first base layer 11 from the base layer-attached liquid crystal layer laminate 46, the first liquid crystal layer 12, the liquid crystal layer adhesive layer 34, the second liquid crystal layer 22, and the second base layer 21 are removed. A liquid crystal layer laminate 47 (first optical functional layer) containing these in this order is obtained (FIG. 4(d)).

Next, a step of preparing a polarizing plate 61 with a composition layer (FIG. 1(a)) is performed. As described in the previous embodiment, the step of preparing the polarizing plate 61 with a composition layer includes applying the polarizing plate adhesive layer 36 on one surface (the other adhesive surface) of the polarizing plate 60 (second optical functional layer). This is a step of providing an adhesive composition layer 36a (adhesive composition layer) for a polarizing plate to form a polarizing plate. In this embodiment, the polarizing plate adhesive layer 36 is a cured adhesive layer, and the polarizing plate adhesive composition layer 36a is formed by applying an adhesive to one surface of the polarizing plate 60. In this embodiment, the surface of the polarizing plate 60 on which the polarizing plate adhesive composition layer 36a is provided is the exposed surface exposed by peeling off the base layer after polymerizing the polymerizable liquid crystal compound on the base layer. shall not be. Thereafter, the polarizing plate adhesive composition layer 36a of the prepared polarizing plate 61 with a composition layer and the first liquid crystal layer 12 side (one adhesive surface, exposed surface) of the liquid crystal layer laminate 47 (first optical functional layer) (FIG. 5(a)), and form an adhesive layer 36 for a polarizing plate from the adhesive composition layer 36a for a polarizing plate to obtain an optical laminate 56 with a base material layer (optical laminate). (Figure 5(b)). As shown in FIG. 5B, the optical laminate 56 with a base material layer includes a polarizing plate 60, a polarizing plate adhesive layer 36, a first liquid crystal layer 12, a liquid crystal layer adhesive layer 34, a second liquid crystal layer 22, and the second base material layer 21 in this order.

The adhesive for forming the adhesive layer 36 for a polarizing plate, the adhesive coating device, and the method for forming the adhesive layer 36 for a polarizing plate from the adhesive composition layer 36a for a polarizing plate are described in the previous embodiment. This can be carried out in the same manner as in the case of forming the adhesive layer 30 for liquid crystal layer which is a hardened layer.

The method for manufacturing the optical laminate 57 further includes a step of peeling off the second base layer 21 from the base layer-attached optical laminate 56 (FIG. 5(c)), and a step of peeling off the second base layer 21. It includes a step (FIG. 5(d)) of forming an adhesive composition layer 35 for optical elements on the exposed second liquid crystal layer 22 side to obtain an optical laminate 58 (optical laminate) with an adhesive composition layer. Good too. As shown in FIG. 5D, the optical laminate 58 with an adhesive composition layer includes a polarizing plate 60, an adhesive layer for polarizing plate 36, a first liquid crystal layer 12, an adhesive layer for liquid crystal layer 34, and a second liquid crystal layer 22. , and an optical element adhesive composition layer 35 in this order.

In the method for manufacturing the optical laminate 57 of this embodiment, as shown in FIGS. In the case where the polarizing plate adhesive composition layer 36a is laminated via the polarizing plate adhesive composition layer 36a, the polarizing plate adhesive composition layer 36a is formed on the polarizing plate 60. In this way, when laminating the first liquid crystal layer 12 side of the liquid crystal layer laminate 47 and the polarizing plate 60 via the polarizing plate adhesive composition layer 36a, The polarizing plate adhesive composition layer 36a is not formed on the exposed surface exposed by peeling off the first base layer 11, and the polarizing plate adhesive composition layer 36a is not formed on one surface of the polarizing plate 60 other than this exposed surface. A material layer 36a is formed. Therefore, in the method for manufacturing the optical laminate 57 described above, damage to the first liquid crystal layer 12 by the coating device that applies the adhesive composition for a polarizing plate and the conveyance roll that conveys the liquid crystal layer laminate 47 is suppressed. It is thought that it is possible to suppress poor appearance and deterioration of optical performance of the optical laminate.

Furthermore, bonding by applying the adhesive used to form the polarizing plate adhesive layer 36, which is an adhesive cured layer, can be carried out using simple equipment, which is industrially advantageous. As described above, the exposed surface exposed by peeling off the base material layer from the liquid crystal layer with the base material layer is likely to be scratched by an adhesive coating device, etc., but according to the manufacturing method of the present invention, the adhesive As the surface to which the agent is applied, a surface that is not the exposed surface exposed by peeling off the base material layer from the liquid crystal layer with the base material layer is selected. Therefore, even when an adhesive is used to form the polarizing plate adhesive layer 36, it is considered that it is easy to suppress poor appearance and deterioration of optical performance of the optical laminate 57.

Further, when the liquid crystal layer adhesive layer 34 is an adhesive layer, if the liquid crystal layer adhesive composition layer 34a is formed on the first liquid crystal layer 12 side of the liquid crystal layer laminate 47 shown in FIG. 4(d), the liquid crystal layer It is presumed that the first liquid crystal layer 12 is more likely to be damaged because the adhesive layer 34 has lower rigidity than when it is a cured adhesive layer. In the method for manufacturing the optical laminate 57 of the present embodiment, even when the liquid crystal layer laminate 47 is one in which the first liquid crystal layer 12 and the second liquid crystal layer 22 are laminated via an adhesive layer, the polarized light Since the polarizing plate adhesive composition layer 36a is formed on the plate 60, when the liquid crystal layer laminate 47 and the polarizing plate 60 are laminated, damage to the first liquid crystal layer 12 can be easily suppressed, and optical It is thought that poor appearance and deterioration of optical performance of the laminate can be easily suppressed.

In addition, the first liquid crystal layer with a base material layer 10, the second liquid crystal layer with a base material layer 20, the liquid crystal layer with a composition layer 26, and the polarized light with a composition layer, which are used to manufacture the optical laminate in this embodiment. It is preferable that the plate 61 and the film-like product such as a laminate obtained using the plate 61 are long film-like products, and it is preferable to carry out each step while continuously conveying these. The width direction W is a direction perpendicular to the length direction of the film-like material.

The method for manufacturing an optical laminate according to this embodiment may be modified as shown in the following modification example. Furthermore, the embodiments described above and the modifications shown below may be combined arbitrarily.

(Modification 1 of Embodiment 2)
In the above, when obtaining the liquid crystal layer laminate 46 with a base material layer, the liquid crystal layer 26 with a composition layer in which the adhesive composition layer 34a for a liquid crystal layer is formed on the second liquid crystal layer 20 with a base material layer (see FIG. Although the case where a)) is used has been described as an example, the present invention is not limited thereto. The adhesive composition layer for a liquid crystal layer may be formed on the first liquid crystal layer 12 side of the first liquid crystal layer 10 with a base material layer, or on the first liquid crystal layer 12 side of the first liquid crystal layer 10 with a base material layer and the base material layer. It may be formed on both sides of the second liquid crystal layer 22 of the second liquid crystal layer 20 with a material layer. Then, the first liquid crystal layer 12 side of the first liquid crystal layer 10 with a base material layer and the second liquid crystal layer 22 side of the second liquid crystal layer 20 with a base material layer are pasted via this adhesive composition layer for liquid crystal layer. In addition, an adhesive layer for a liquid crystal layer may be formed from the adhesive composition layer for a liquid crystal layer. In this case as well, the exposed surface exposed by peeling off the first base layer 11 from the first liquid crystal layer with base layer 10 or the exposed surface exposed by peeling off the second base layer 21 from the second liquid crystal layer with base layer 20 Since the liquid crystal layer adhesive composition layer 34a is not formed on the exposed surfaces, and the liquid crystal layer adhesive composition layer is formed on surfaces other than these exposed surfaces, the first liquid crystal layer 12 and the second liquid crystal layer It is believed that by suppressing the liquid crystal layer 22 from being scratched, it is possible to suppress poor appearance and deterioration of optical performance of the optical laminate.

(Modification 2 of Embodiment 2)
Similarly to the previous embodiment, in this embodiment as well, the first liquid crystal layer with a base material layer may have a first alignment layer between the first base material layer and the first liquid crystal layer, The second liquid crystal layer with a base layer may have a second alignment layer between the second base layer and the second liquid crystal layer. The description of the case where the first orientation layer and the second orientation layer are provided is the same as that described in the modification of the previous embodiment, so the description thereof will be omitted.

Although the embodiments of the present invention and their modifications have been described above, the present invention is not limited to these embodiments and their modifications. For example, each structure and modification of each of the above embodiments and its modifications It is also possible to perform each step in combination. Hereinafter, each matter common to all the embodiments and their modifications will be described in detail.

(optical laminate)
The optical laminate is not particularly limited as long as it includes a first optical functional layer, an adhesive layer that is a cured adhesive layer, and a second optical functional layer. For example, in the optical laminate 52 shown in FIG. 3(b) and the optical laminate 57 shown in FIG. 5(b), the polarizing plate 60 is a linear polarizing plate, the first liquid crystal layer 12 is a 1/2 wavelength plate, and the By using the second liquid crystal layer 22 as a quarter wavelength plate, the optical laminates 52 and 57 can be used as circularly polarizing plates. Alternatively, the polarizing plate 60 may be a linear polarizing plate, the first liquid crystal layer 12 may be a quarter wavelength plate with reverse wavelength dispersion, and the second liquid crystal layer 22 may be a positive C plate, or the first liquid crystal layer 12 may be a positive C plate. The optical laminates 52 and 57 can also be made into circularly polarizing plates by using a C plate and using the second liquid crystal layer 22 as a quarter-wave plate with reverse wavelength dispersion.

(First optical functional layer and second optical functional layer)
The first optical functional layer and the second optical functional layer (hereinafter both may be collectively referred to as "optical functional layer") include a liquid crystal layer; a polarizing layer, and a polarizing layer with a protective layer formed on at least one side of the polarizing layer. Polarizing functional layer such as a polarizing plate with a protective film in which a protective film is laminated on at least one side of the plate or polarizing plate; reflective film; transflective film; brightness enhancement film; optical compensation film; film with anti-glare function; retardation Examples include films, etc., and may include one of these, or may have a multilayer structure including two or more. Further, when the optical functional layer includes a liquid crystal layer, this liquid crystal layer may be a retardation layer or a polarizing layer. In this specification, the term "polarizing layer" refers to a linearly polarizing layer that has the property of transmitting linearly polarized light having a plane of vibration perpendicular to the absorption axis when unpolarized light is incident thereon.

(Linear polarizing layer (polarizing layer))
The polarizing layer (linearly polarizing layer) is preferably one in which a dichroic dye such as iodine is adsorbed and oriented on an oriented polyvinyl alcohol resin film. The polarizing layer may be a single-layer polyvinyl alcohol resin film (orientated polyvinyl alcohol molecules contained in the polyvinyl alcohol resin film) in which a dichroic dye is adsorbed and oriented. It may be a laminated film of two or more layers provided with a polyvinyl alcohol resin layer in which a sex dye is adsorbed and oriented. Further, the polarizing layer may be a cured film obtained by aligning a dichroic dye to a polymerizable liquid crystal compound and polymerizing the polymerizable liquid crystal compound. Such polarizing layers can be manufactured by various methods known in the art.

(Polarizer)
A polarizing plate is typically a polarizing plate formed by laminating a protective layer (protective film) on one or both sides of a polarizing layer in which a dichroic dye is adsorbed and oriented on a polyvinyl alcohol resin film. As this protective layer, for example, one made of a resin material having excellent transparency, mechanical strength, thermal stability, stretchability, etc. is used. Specifically, polyolefin resins such as polyethylene and polypropylene; cyclic polyolefin resins such as norbornene polymers; polyester resins such as polyethylene terephthalate and polyethylene naphthalate; (meth)acrylic acid, poly(meth)methyl acrylate, etc. (meth)acrylic acid resins; cellulose ester resins such as triacetyl cellulose, diacetyl cellulose and cellulose acetate propionate; vinyl alcohol resins such as polyvinyl alcohol and polyvinyl acetate; polycarbonate resins; polystyrene resins; Arylate resins; polysulfone resins; polyethersulfone resins; polyamide resins; polyimide resins; polyetherketone resins; polyphenylene sulfide resins; polyphenylene oxide resins, and mixtures and copolymers thereof. I can do it. Among these resins, it is preferable to use any one of a cyclic polyolefin resin, a polyester resin, a cellulose ester resin, and a (meth)acrylic acid resin, or a mixture thereof. In addition, the above-mentioned "(meth)acrylic acid" means "at least one kind of acrylic acid and methacrylic acid."

The protective layer may be a single layer made of one type of resin material or a mixture of two or more types, or may have a multilayer structure of two or more layers. When having a multilayer structure, the resins forming each layer may be the same or different. When the protective layer is a film made of a resin material, arbitrary additives may be added to the protective layer. Examples of additives include ultraviolet absorbers, antioxidants, lubricants, plasticizers, mold release agents, color inhibitors, flame retardants, nucleating agents, antistatic agents, pigments, and colorants.

The thickness of the polarizing layer in which a dichroic dye is adsorbed and oriented on a polyvinyl alcohol resin film is preferably 20 μm or less, more preferably 10 μm or less.

Particularly preferred are polarizing plates and polarizing layers with a protective layer bonded to only one side (hereinafter referred to as "single-protected polarizing plate"). As described above, the first liquid crystal layer and the second liquid crystal layer are formed from a polymerizable liquid crystal compound and are extremely thin films. When the linear polarizing plate is a single-protection polarizing plate, its thickness is small, and as a result, the thickness of the optical laminate of the present invention can be reduced. Therefore, for example, when the optical laminate of the present invention is a circularly polarizing plate and an organic EL display device equipped with this circularly polarizing plate is a flexible organic EL display device that can be folded or rolled, It is extremely advantageous because it hardly affects bending, winding, etc. The thickness of the protective layer in the single protection polarizing plate can be optimized depending on the thickness of the polarizing layer itself, but in order to ensure good flexibility of the optical laminate of the present invention, the thickness is preferably 50 μm or less, More preferably, the thickness is 30 μm or less.

As the above-mentioned single-protection polarizing plate, for example, one disclosed in JP-A No. 2016-122025 and the like can be used.

Furthermore, as described above, the polarizing layer may be a cured film obtained by aligning a dichroic dye to a polymerizable liquid crystal compound and polymerizing the polymerizable liquid crystal compound. In this case, the polarizing layer is usually formed by coating a composition containing a polymerizable liquid crystal compound and a dichroic dye on a base material layer or an alignment layer provided thereon, and drying it. It can be obtained by polymerizing and curing the polymerizable liquid crystal compound contained in the coating film by irradiating energy rays. The thus obtained laminate of the base material and the polarizing layer (cured film) can be used as a single-protection polarizing plate.

The thickness of the base material layer for forming the above-mentioned cured film is not particularly limited, but in general, from the viewpoint of workability such as strength and handleability, it is preferably 1 to 300 μm, more preferably 10 to 200 μm. The thickness is preferably 30 to 120 μm, and more preferably 30 to 120 μm.

(First base layer and second base layer)
The first base layer and the second base layer (hereinafter both may be collectively referred to as "base layer") are preferably films made of a resin material. Similar to the material forming the protective film of the polarizing plate described above, this resin material is also a resin material that is excellent in transparency, mechanical strength, thermal stability, stretchability, etc., for example. As typical examples and preferred examples of the resin material, the resin materials exemplified as the protective layer of the polarizing plate can be used.

The base material layer may be a single layer made of one type of resin material or a mixture of two or more types, or may have a multilayer structure of two or more layers. When having a multilayer structure, the resin materials forming each layer may be the same or different. When the base layer is a film made of a resin material, arbitrary additives may be added to the base layer. Examples of additives include ultraviolet absorbers, antioxidants, lubricants, plasticizers, mold release agents, color inhibitors, flame retardants, nucleating agents, antistatic agents, pigments, and colorants.

The thickness of the base material layer for forming the liquid crystal layer is not particularly limited, but in general, from the viewpoint of workability such as strength and handleability, it is preferably 1 to 300 μm, more preferably 10 to 200 μm, More preferably, the thickness is 30 to 120 μm.

(First alignment layer and second alignment layer)
The first alignment layer and the second alignment layer (hereinafter, both may be collectively referred to as "alignment layers") that may be included in the optical laminate are polymerizable layers contained in the liquid crystal layer formed thereon. It has alignment regulating power to align the liquid crystal compound in a desired direction. Examples of the alignment layer include an alignment polymer layer formed of an alignment polymer, a photoalignment polymer layer formed of a photoalignment polymer, and a groove alignment layer having an uneven pattern or a plurality of grooves on the layer surface. I can do it. The thickness of the alignment layer is usually 10 to 500 nm, preferably 10 to 200 nm.

The oriented polymer layer can be formed by applying a composition in which an oriented polymer is dissolved in a solvent to the base layer, removing the solvent, and performing a rubbing treatment if necessary. In this case, in an oriented polymer layer formed of an oriented polymer, the alignment regulating force can be arbitrarily adjusted by adjusting the surface condition of the oriented polymer and rubbing conditions.

The photo-alignable polymer layer can be formed by applying a composition containing a polymer having a photo-reactive group or a monomer and a solvent to a base layer and irradiating the layer with polarized light. In this case, the alignment regulating force in the photo-alignable polymer layer can be arbitrarily adjusted by adjusting the polarized light irradiation conditions for the photo-alignable polymer.

The groove alignment layer can be formed, for example, by exposing and developing the surface of a photosensitive polyimide film through an exposure mask having pattern-shaped slits to form a concavo-convex pattern, or by applying activation to a plate-shaped master having grooves on the surface. A method of forming an uncured layer of energy ray curable resin, transferring this layer to a base material layer and curing it, forming an uncured layer of active energy ray curable resin on the base material layer, It can be formed by a method of forming unevenness by pressing a roll-shaped master having unevenness, etc., and then hardening it.

(First liquid crystal layer and second liquid crystal layer)
The first liquid crystal layer and the second liquid crystal layer (hereinafter, both may be collectively referred to as "liquid crystal layer") are both formed using a polymerizable liquid crystal compound, and this polymerizable liquid crystal compound is a well-known polymerizable liquid crystal compound. You can use the following. The type of polymerizable liquid crystal compound is not particularly limited, and rod-like liquid crystal compounds, discotic liquid crystal compounds, and mixtures thereof can be used. Here, the polymerizable liquid crystal compound for forming the quarter wavelength plate with reverse wavelength dispersion is preferably a rod-shaped liquid crystal compound, for example, the polymerizable liquid crystal compound described in JP-A-2011-207765. When using such a polymerizable liquid crystal compound, a composition for forming a liquid crystal layer containing a polymerizable liquid crystal compound, a solvent, and optionally various additives is applied onto the alignment layer to form a coating film. By curing this coating film, a liquid crystal layer, which is a cured liquid crystal layer, can be formed. Alternatively, the liquid crystal layer may be formed by coating the composition for forming a liquid crystal layer on the base material layer to form a coating film, and stretching this coating film together with the base material layer. The liquid crystal layer may be a retardation layer.

The composition for forming a liquid crystal layer may contain a polymerization initiator, a reactive additive, a leveling agent, a polymerization inhibitor, etc. in addition to the above-described polymerizable liquid crystal compound and solvent. As the polymerizable liquid crystal compound, solvent, polymerization initiator, reactive additive, leveling agent, polymerization inhibitor, etc., known ones can be used as appropriate.

(Adhesive layer for polarizing plate)
The adhesive layer for a polarizing plate can be formed from an adhesive, a pressure-sensitive adhesive, or a combination thereof, and is usually one layer, but may be two or more layers. When the adhesive layer for a polarizing plate consists of two or more layers, each layer may be formed of the same material or different materials. Examples of the adhesive for forming the adhesive layer for the polarizing plate include the same adhesives as those used for the adhesive layer for the liquid crystal layer described above.

The adhesive used in the adhesive layer for polarizing plates is a composition that uses (meth)acrylic resin, styrene resin, silicone resin, etc. as a base polymer and adds a crosslinking agent such as an isocyanate compound, epoxy compound, or aziridine compound. can be mentioned.

The surface of the layer on which the adhesive layer for polarizing plate is formed may be subjected to surface treatment such as corona treatment, plasma treatment, flame treatment, etc., if necessary.

(Adhesive layer for liquid crystal layer)
The adhesive layer for liquid crystal layer is an adhesive layer provided between the first liquid crystal layer and the second liquid crystal layer and used for bonding these two liquid crystal layers together. The liquid crystal layer adhesive layer may be in direct contact with the first liquid crystal layer and the second liquid crystal layer, but may be in direct contact with the first alignment layer provided on the first liquid crystal layer or the second alignment layer provided on the second liquid crystal layer. It may be in direct contact with the alignment layer.

The adhesive layer for the liquid crystal layer can be formed from an adhesive, a pressure-sensitive adhesive, or a combination thereof, and is usually one layer, but may be two or more layers. When the adhesive layer for a liquid crystal layer consists of two or more layers, each layer may be formed of the same material or different materials. Examples of the adhesive forming the adhesive layer for the liquid crystal layer include those similar to the adhesives and pressure-sensitive adhesives used for the adhesive layer for the liquid crystal layer and the adhesive layer for the polarizing plate described above. The surface of the layer on which the adhesive layer for a liquid crystal layer is formed may be subjected to surface treatment such as corona treatment, plasma treatment, flame treatment, etc., if necessary.

The optical laminate of the present invention is a circularly polarizing plate, and when this circularly polarizing plate is applied to a flexible organic EL display device that can be bent or wound, the adhesive layer for the liquid crystal layer is an adhesive cured layer. It is preferable that This also occurs when the optical laminate, which is a circularly polarizing plate, is bent or wound as the flexible organic EL display device is bent or wound. This is because it is easy to suppress the formation of wrinkles in between.

(Adhesive composition layer for optical elements)
The adhesive composition layer for optical elements can be formed from an adhesive, a pressure-sensitive adhesive, or a combination thereof, and is usually one layer, but may be two or more layers. When the adhesive composition layer for optical elements consists of two or more layers, each layer may be formed of the same material or different materials. Examples of the adhesive and pressure-sensitive adhesive constituting the adhesive composition layer for optical elements include those similar to the adhesives and pressure-sensitive adhesives used in the above-described adhesive layer for liquid crystal layer and adhesive layer for polarizing plate. The adhesive composition layer for optical elements is preferably formed using an adhesive. The surface of the layer on which the adhesive composition layer for optical elements is formed may be subjected to surface treatment such as corona treatment, plasma treatment, flame treatment, etc., if necessary. The optical element adhesive composition layer is preferably an adhesive layer formed using an adhesive.

EXAMPLES Hereinafter, the present invention will be explained in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples. "%" and "parts" in the examples are mass % and parts by mass unless otherwise specified.

[Preparation of adhesive composition]
After mixing the cationic curable components a1 to a3 shown below and a cationic polymerization initiator, the cationic polymerization initiator and sensitizer shown below are further mixed and defoamed to prepare a photocurable adhesive composition. did. Note that the following blending amounts are based on the solid content.
・Cationic curable component a1 (70 parts):
3',4'-epoxycyclohexylmethyl 3',4'-epoxycyclohexane carboxylate (product name: CEL2021P, manufactured by Daicel Corporation)
・Cationic curable component a2 (20 parts):
Neopentyl glycol diglycidyl ether (trade name: EX-211, manufactured by Nagase ChemteX Co., Ltd.)/Cationic curable component a3 (10 parts):
2-Ethylhexyl glycidyl ether (product name: EX-121, manufactured by Nagase ChemteX Corporation)
・Cationic polymerization initiator (2.25 parts (solid content)):
Product name: CPI-100 (manufactured by San-Apro Co., Ltd.) 50% propylene carbonate solution/sensitizer (2 parts):
1,4-diethoxynaphthalene

・溶剤（９５部）：シクロペンタノン [Example 1]
(Preparation of composition for forming photoalignment layer)
A composition for forming a photo-alignment layer was obtained by mixing the following components and stirring the resulting mixture at a temperature of 80° C. for 1 hour.
・Photoalignable material (5 parts):

・Solvent (95 parts): cyclopentanone

・重合性液晶化合物Ａ２（２０部）：

・重合開始剤（６部）：
２－ジメチルアミノ－２－ベンジル－１－（４－モルホリノフェニル）ブタン－１－オン（イルガキュア３６９；チバスペシャルティケミカルズ社製）
・レベリング剤（０．１部）：
ポリアクリレート化合物（ＢＹＫ－３６１Ｎ；ＢＹＫ－Ｃｈｅｍｉｅ社製）
・溶剤（４００部）：シクロペンタノン (Preparation of liquid crystal layer forming composition (A))
A liquid crystal layer forming composition (A) was obtained by mixing the following components and stirring the resulting mixture at 80° C. for 1 hour. Polymerizable liquid crystal compound A1 can be synthesized by the method for synthesizing compound (A11-1) described in JP-A-2011-207765. Polymerizable liquid crystal compound A2 can be synthesized by the method for synthesizing compound (x-1) described in JP-A-2010-31223.
・Polymerizable liquid crystal compound A1 (80 parts):

・Polymerizable liquid crystal compound A2 (20 parts):

・Polymerization initiator (6 parts):
2-dimethylamino-2-benzyl-1-(4-morpholinophenyl)butan-1-one (Irgacure 369; manufactured by Ciba Specialty Chemicals)
・Leveling agent (0.1 part):
Polyacrylate compound (BYK-361N; manufactured by BYK-Chemie)
・Solvent (400 parts): cyclopentanone

(Manufacture of liquid crystal layer with base layer (1))
A polyethylene terephthalate (PET) film with a thickness of 100 μm was used as the base layer, and this PET film was treated with a corona treatment device (AGF-B10, manufactured by Kasuga Denki Co., Ltd.) at an output of 0.3 kW and a processing speed of 3 m/min. Treated once. The composition for forming a photo-alignment layer was applied to the corona-treated surface using a bar coater, dried at 80°C for 1 minute, and then irradiated with a polarized UV irradiation device (SPOT CURE SP-7; manufactured by Ushio Inc.). A photo-alignment layer was obtained by performing polarized UV exposure with an integrated light amount of 100 mJ/cm ² using the photo-alignment layer. The thickness of the obtained photo-alignment layer was measured using a laser microscope (LEXT, manufactured by Olympus Corporation) and was found to be 100 nm.

Subsequently, the liquid crystal layer forming composition (A) was applied onto the photo-alignment layer using a bar coater, dried at 120°C for 1 minute, and then heated using a high-pressure mercury lamp (Unicure VB-15201BY-A, Ushio Inc.). A liquid crystal layer as a retardation layer is formed by irradiating ultraviolet rays (under a nitrogen atmosphere, wavelength: 365 nm, cumulative light amount at wavelength 365 nm: 1000 mJ/cm ² ), and a base material layer is attached. A liquid crystal layer (1) was obtained. The thickness of the liquid crystal layer was 2 μm.

Regarding the obtained liquid crystal layer with a base material layer (1), the adhesive composition described above was applied to the opposite side of the liquid crystal layer from the base material layer using a bar coater, and the coated surface was visually observed, and no scratches were found. was not often observed.

[Comparative example 1]
A liquid crystal layer with a base material layer (1) was obtained in the same manner as in Example 1. The liquid crystal layer side of the obtained liquid crystal layer with base material layer (1) was bonded to a glass substrate [alkali-free glass manufactured by Corning Corporation] via a sheet-like adhesive having a thickness of 5 μm [NCF #L2 manufactured by Lintec Corporation]. Eagle Only the base layer was peeled off, and the photoalignment layer remained without being peeled off. The adhesive composition described above was applied to the peeling side of the base material layer of the liquid crystal layer with a glass substrate using a bar coater, and the coated surface was visually observed. As a result, the base material layer observed in Example 1 was More scratches were observed on the liquid crystal layer side of the attached liquid crystal layer (1) than on the surface to which the adhesive composition was applied.

From the results of Example 1 and Comparative Example 1, the surface of the liquid crystal layer opposite to the base material layer is less likely to be damaged by coating equipment or conveyance rolls, so when used in optical laminates, there is a risk of poor appearance or poor optical performance. It is thought that it is unlikely to cause a decline.

[Example 2]
(Preparation of composition for forming alignment layer)
A composition for forming an alignment layer was obtained by adding 2-butoxyethanol to Sunever SE-610 (manufactured by Nissan Chemical Industries, Ltd.), which is a commercially available alignment polymer. The resulting composition for forming an alignment layer had a solid content of 1% based on the total amount of the composition, and a solvent content of 99% based on the total amount of the composition. The solid content of Sunever SE-610 was calculated from the concentration stated in the delivery specifications.

・重合開始剤（０．５％）：
イルガキュア（登録商標）９０７（ＢＡＳＦジャパン社製）
・レベリング剤（０．１％）：
ＢＹＫ３６１Ｎ（ビックケミージャパン製）
・反応添加剤（１．１％）：
Ｌａｒｏｍｅｒ（登録商標）ＬＲ－９０００（ＢＡＳＦジャパン社製）
・溶剤（７９．１％）：プロピレングリコール１－モノメチルエーテル２－アセタート
厚み３８μｍのポリエチレンテレフタレート（ＰＥＴ）フィルムを、コロナ処理装置（ＡＧＦ－Ｂ１０、春日電機株式会社製）を用いて出力０．３ｋＷ、処理速度３ｍ／分の条件で１回処理した。コロナ処理を施した表面に、配向層形成用組成物をバーコーターを用いて塗布し、９０℃で１分間乾燥し、配向層を得た。得られた配向層の厚みをレーザー顕微鏡（ＬＥＸＴ、オリンパス株式会社製）で測定したところ、３４ｎｍであった。 (Preparation of liquid crystal layer forming composition (B))
The following components were mixed, and the resulting mixture was stirred at 80° C. for 1 hour, and then cooled to room temperature to obtain a composition for forming a liquid crystal layer (B).
・Polymerizable liquid crystal compound LC242 (manufactured by BASF) (19.2%):

・Polymerization initiator (0.5%):
Irgacure (registered trademark) 907 (manufactured by BASF Japan)
・Leveling agent (0.1%):
BYK361N (manufactured by BYK Chemie Japan)
・Reactive additive (1.1%):
Laromer (registered trademark) LR-9000 (manufactured by BASF Japan)
・Solvent (79.1%): Propylene glycol 1-monomethyl ether 2-acetate Polyethylene terephthalate (PET) film with a thickness of 38 μm was treated with a corona treatment device (AGF-B10, manufactured by Kasuga Denki Co., Ltd.) with an output of 0.3 kW. , and was processed once at a processing speed of 3 m/min. A composition for forming an alignment layer was applied to the corona-treated surface using a bar coater and dried at 90° C. for 1 minute to obtain an alignment layer. The thickness of the obtained alignment layer was measured with a laser microscope (LEXT, manufactured by Olympus Corporation) and was found to be 34 nm.

Subsequently, the liquid crystal layer forming composition (B) was applied onto the alignment layer using a bar coater, dried at 90°C for 1 minute, and then heated using a high-pressure mercury lamp (Unicure VB-15201BY-A, Ushio Inc. A liquid crystal layer as a retardation layer is formed by irradiating ultraviolet rays (under nitrogen atmosphere, wavelength: 365 nm, cumulative light amount at wavelength 365 nm: 1000 mJ/cm ² ) using Layer (2) was obtained. The thickness of the liquid crystal layer was 1 μm.

Regarding the obtained liquid crystal layer with a base layer (2), the adhesive composition described above was applied to the opposite side of the liquid crystal layer from the base layer using a bar coater, and the coated surface was visually observed, and no scratches were found. was not often observed.

[Comparative example 2]
A liquid crystal layer with a base layer (2) was obtained in the same manner as in Example 2. The liquid crystal layer side of the obtained liquid crystal layer with base material layer (1) was bonded to a glass substrate [alkali-free glass manufactured by Corning Corporation] via a sheet-like adhesive having a thickness of 5 μm [NCF #L2 manufactured by Lintec Corporation]. Eagle The orientation layer was also peeled off along with the peeling of the base layer. The adhesive composition described above was applied to the peeling side of the base layer of the liquid crystal layer with a glass substrate using a bar coater, and the coated surface was visually observed. More scratches were observed on the liquid crystal layer side of the attached liquid crystal layer (2) than on the surface to which the adhesive composition was applied.

From the results of Example 2 and Comparative Example 2, the surface of the liquid crystal layer opposite to the base material layer is less likely to be damaged by coating equipment or conveyance rolls, so when used in optical laminates, there is no possibility of poor appearance or poor optical performance. It is thought that it is unlikely to cause a decline.

10 first liquid crystal layer with base material layer, 11 first base material layer (base material layer), 12 first liquid crystal layer (liquid crystal layer), 20 second liquid crystal layer with base material layer (second optical functional layer), 21 2nd base material layer, 22 2nd liquid crystal layer (liquid crystal layer), 25 liquid crystal layer with composition layer, 26 liquid crystal layer with composition layer, 30 adhesive layer for liquid crystal layer (adhesive layer), 30a adhesive composition for liquid crystal layer layer (adhesive composition layer), 34 adhesive layer for liquid crystal layer, 34a adhesive composition layer for liquid crystal layer, 35 adhesive composition layer for optical element, 36 adhesive layer for polarizing plate (adhesive layer, adhesive layer for polarizing functional layer) , 36a adhesive composition layer for polarizing plate (adhesive composition layer), 41 first liquid crystal layer with polarizing plate (liquid crystal layer with polarizing function layer, optical laminate), 42 second liquid crystal layer with polarizing plate (first optical functional layer, optical laminate), 46 liquid crystal layer laminate with base material layer, 47 liquid crystal layer laminate (first optical functional layer), 51 optical laminate with base material layer (optical laminate), 52 optical laminate , 53 Optical laminate with adhesive composition layer (optical laminate), 56 Optical laminate with base layer (optical laminate), 57 Optical laminate, 58 Optical laminate with adhesive composition layer (optical laminate), 60 Polarizing plate (first optical functional layer, second optical functional layer, polarizing functional layer), 61 Polarizing plate with composition layer (second optical functional layer), W width direction.

Claims (6)

A method for producing an optical laminate including a first optical functional layer, an adhesive layer, and a second optical functional layer in this order,
The adhesive layer is an adhesive cured layer in which an adhesive is cured,
The first optical functional layer includes a first liquid crystal layer formed by polymerizing a polymerizable liquid crystal compound on the first base layer, an adhesive layer for the liquid crystal layer, and a polymerizable liquid crystal compound formed on the second base layer. a second liquid crystal layer formed by polymerizing in this order,
The second optical functional layer is a polarizing functional layer including at least a linearly polarizing layer,
The first optical functional layer and the second optical functional layer each have an adhesive surface on the adhesive layer side,
A base layer-attached second base layer comprising the first base layer, the first liquid crystal layer, the liquid crystal layer adhesive layer, the second liquid crystal layer and the second base layer in order from the liquid crystal layer adhesive layer side. a step of preparing a liquid crystal layer laminate with a base material layer having two liquid crystal layers in this order,
One of the adhesive surfaces is an exposed surface exposed by peeling off the first base layer from the base layer-attached liquid crystal layer laminate,
providing an adhesive composition layer for forming the adhesive layer on the other adhesive surface of the adhesive surfaces by applying the adhesive with a bar coater or a gravure coater ;
After laminating the first optical functional layer and the second optical functional layer by laminating the one adhesive surface onto the adhesive composition layer provided on the other adhesive surface, the adhesive composition layer is laminated. A method for producing an optical laminate, comprising: curing the laminate. The method for manufacturing an optical laminate according to claim 1 , further comprising a step of peeling off the second base layer after the curing step. The method for manufacturing an optical laminate according to claim 1 or 2 , wherein the adhesive layer for liquid crystal layer is an adhesive layer. The optical laminate is a circularly polarizing plate,
The first liquid crystal layer and the second liquid crystal layer have the following [a] or [b]:
[a] The first liquid crystal layer is a half-wave plate, and the second liquid crystal layer is a quarter-wave plate.
[b] One of the first liquid crystal layer and the second liquid crystal layer is a reverse wavelength dispersion quarter-wave plate, and the other is a positive C plate;
The method for producing an optical laminate according to any one of claims 1 to 3 , which satisfies the following relationship. Further, a step of preparing a first liquid crystal layer with a base material layer having the first base material layer and the first liquid crystal layer;
The method for producing an optical laminate according to any one of claims 1 to 4 , comprising the step of peeling off the first base layer. 6. The method for manufacturing an optical laminate according to claim 1 , wherein the optical laminate includes an alignment layer on the first base layer side of the first liquid crystal layer.

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