KR-102961414-B1 - Method for manufacturing an optical laminate

KR102961414B1KR 102961414 B1KR102961414 B1KR 102961414B1KR-102961414-B1

Abstract

[Problem] The present invention has the objective of providing a method for manufacturing an optical laminate having a phase difference layer comprising an optical film and a cured layer of a polymerizable liquid crystal compound, wherein wrinkle defects do not easily occur even when the optical laminate is bent with a small radius of curvature. [Solution] A method for manufacturing an optical laminate is provided, wherein the optical laminate comprises, in this order, an optical film, a cured adhesive layer which is a cured layer of an active energy beam curable adhesive, and a phase difference layer which is a cured layer of a polymerizable liquid crystal compound. The manufacturing method comprises, in this order, a process of laminating the optical film, the active energy beam curable adhesive layer, and the phase difference layer so that the active energy beam curable adhesive layer and the phase difference layer are in contact, a process of maintaining under conditions satisfying at least one of (1) maintaining at a temperature of 30°C or higher for 2 hours or more, (2) maintaining under vibration conditions for 2 hours or more, and (3) maintaining for 48 hours or more, and a process of curing the active energy beam curable adhesive layer to form a cured adhesive layer.

Inventors

가토 신야
데자키 히카리

Assignees

스미또모 가가꾸 가부시키가이샤

Dates

Publication Date: 20260507
Application Date: 20201111
Priority Date: 20191223

Claims (7)

As a method for manufacturing an optical laminate, The above optical laminate comprises, in this order, an optical film, a cured adhesive layer which is a cured layer of an active energy beam curable adhesive, and a phase difference layer which is a cured layer of a polymerizable liquid crystal compound. The above manufacturing method is, A process of laminating the above optical film, the active energy beam curable adhesive layer, and the phase difference layer such that the active energy beam curable adhesive layer and the phase difference layer are in contact, and (1) ~ (3) : (1) Maintain at a temperature of 30℃ or higher for at least 2 hours, (2) Maintain for at least 2 hours under vibration conditions with a frequency of 5 Hz or higher and an amplitude of 0.5 mm or higher. (3) Maintain at 5℃ or higher for at least 48 hours. A process maintained under conditions satisfying one or more of the following, and A process of curing the active energy beam curable adhesive layer to form the cured adhesive layer. A method for manufacturing an optical laminate comprising in this order.
As a method for manufacturing an optical laminate, The above optical laminate comprises, in this order, an optical film, a cured adhesive layer which is a cured layer of an active energy beam curable adhesive, and a phase difference layer which is a cured layer of a polymerizable liquid crystal compound. The above manufacturing method is, A process for preparing a laminate comprising a base film and a phase difference layer laminated thereon, and A process of peeling the substrate film from the phase difference layer at a peeling speed of 50 m/min or more, and A process of laminating an optical film through an active energy beam curable adhesive layer on the peeled surface of the phase difference layer after peeling off the above-mentioned film, and A process of curing the active energy beam curable adhesive layer to form the cured adhesive layer. A method for manufacturing an optical laminate comprising in this order.
In paragraph 1 or 2, A method for manufacturing an optical laminate, wherein the above optical film includes a linear polarizer.
In paragraph 3, A method for manufacturing an optical laminate, wherein, in the above lamination process, the optical film, the active energy line curable adhesive layer, and the phase difference layer are laminated such that the linear polarizer and the active energy line curable adhesive layer are in contact.
A phase difference layer comprising an optical film, a cured adhesive layer which is a cured layer of an active energy beam curable adhesive, and a cured layer of a polymerizable liquid crystal compound is provided in this order. The above-mentioned cured adhesive layer and the above-mentioned phase difference layer are in contact, and The surface on the cured adhesive layer side in the phase difference layer above is as follows (a) to (d): (a) Arithmetic mean roughness Sa is 0.065 μm or greater and 0.150 μm or less, (b) The root mean square height Sq is greater than or equal to 0.085 μm, (c) The interface development area ratio Sdr is 0.2% or more, (d) The root mean square slope Sdq is 0.065 or greater. An optical laminate satisfying one or more of the following.
In paragraph 5, An optical laminate comprising a linear polarizer in the above optical film.
In paragraph 6, An optical laminate in which the above linear polarizer and the above cured adhesive layer are in contact.

Description

Method for manufacturing an optical laminate The present invention relates to a method for manufacturing an optical laminate and also to an optical laminate. In image display devices such as organic EL display devices, an optical laminate (elliptical polarizer) combining a polarizer (linear polarizer) and a phase difference layer is sometimes used for purposes such as preventing external light reflection by metal electrodes. For example, Japanese Patent Publication No. 2018-017996 (Patent Document 1) describes manufacturing an elliptical polarizer by laminating a polarizer and a phase difference layer formed of a polymerizable liquid crystal compound through a UV-curable adhesive layer, and curing the adhesive layer by UV irradiation. [Fig. 1] This is a schematic cross-sectional view illustrating an example of the layer structure of a laminate obtained by the lamination process in Embodiment 1. [Fig. 2] This is a schematic cross-sectional view illustrating an example of the layer configuration of an optical laminate. [Fig. 3] This is a schematic cross-sectional view illustrating an example of the layer configuration of a laminate prepared in the preparation process of Embodiment 2. [Fig. 4] This is a schematic cross-sectional view illustrating an example of the layer configuration of a straight polarizer. [Fig. 5] This is a schematic cross-sectional view illustrating an example of the layer configuration of a phase difference laminate. [Fig. 6] This is a schematic cross-sectional view illustrating another example of the layer configuration of an optical laminate. [Fig. 7] This is a schematic cross-sectional view illustrating another example of the layer configuration of an optical laminate. [Fig. 8] This is a schematic diagram illustrating the method for evaluating wrinkle defects. [Fig. 9] This is a schematic diagram illustrating the directions of the absorption axis and the ground axis in an optical laminate. Method for manufacturing an optical laminate An optical laminate manufactured by the manufacturing method according to the present invention comprises, in this order, an optical film, a cured adhesive layer (hereinafter also simply referred to as the "cured adhesive layer") which is a cured layer of an active energy beam curable adhesive, and a phase difference layer (hereinafter also simply referred to as the "phase difference layer") which includes a cured layer of a polymerizable liquid crystal compound. The optical laminate manufactured by the manufacturing method according to the present invention can be suitably applied to image display devices such as organic EL display devices. Hereinafter, embodiments of a method for manufacturing an optical laminate according to the present invention will be described with reference to the drawings. Each embodiment shown below may be combined arbitrarily. All drawings are schematic diagrams and may not show actual dimensions. In each of the embodiments described below, the film or layer used in each process may be a long material and the process may be performed continuously, or the film or layer used in each process may be a single sheet and the process may be performed discontinuously. The single sheet may be cut from a long material. [Embodiment 1] The method for manufacturing an optical laminate according to the present embodiment includes the following processes in the order described below. A process of laminating a phase difference layer comprising an optical film, an active energy beam curable adhesive layer, and a cured layer of a polymerizable liquid crystal compound such that the active energy beam curable adhesive layer and the phase difference layer are in contact [lamination process], (1) ~ (3) : (1) Maintain at a temperature of 30℃ or higher for at least 2 hours, (2) Maintain for more than 2 hours under vibration conditions, (3) Maintain for at least 48 hours. A process [maintenance process] maintained under conditions satisfying one or more of the above, and A process for forming a cured adhesive layer by curing an active energy beam-curable adhesive layer [curing process]. [1] Lamination process FIG. 1 is a schematic cross-sectional view illustrating an example of the layer structure of a laminate obtained by the lamination process in the present embodiment. The lamination process is a process of laminating an optical film (10) and a phase difference layer (30) through an active energy beam curable adhesive layer (20) (hereinafter also simply referred to as the "adhesive layer"). In this specification, the active energy beam curable adhesive layer refers to a layer composed of an active energy beam curable adhesive. As the active energy beam curable adhesive, one having the ability to bond the phase difference layer (30) and the optical film (10) is used. In the lamination process, the optical film (10), the adhesive layer (20), and the phase difference layer (30) are laminated so that the adhesive layer (20) and the phase difference layer