TWI860983B - Curable composition, optical laminate and image display device - Google Patents

Abstract

The present invention provides a curable composition containing an oxazoline group-containing polymer (A) and an iodine compound (B); and an optical laminate comprising an optical film and a first cured product layer composed of a cured product of the curable composition; and an image display device containing the same.

Description

Curable composition, optical laminate and image display device

The present invention relates to a curable composition. Furthermore, the present invention relates to an optical laminate including a cured material layer formed by a cured product of the curable composition, and an image display device including the optical laminate.

In recent years, image display devices have been developed for mobile device applications represented by smartphones and tablet-type terminal devices, and for vehicle applications represented by car navigation systems. In these applications, since they may be exposed to harsh environments compared to previous indoor TV applications, improving the durability of the device has become a topic.

Optical components such as optical multilayers that constitute liquid crystal display devices are also required to have similar durability. That is, optical components assembled in liquid crystal display devices are placed in high temperature or high temperature and high humidity environments, or in environments with repeated high and low temperatures. Optical components are required not to deteriorate their optical properties even in such environments.

An optical laminate may include an optical laminate including a cured material layer composed of a cured material of a curable composition. An example of such an optical laminate is a polarizing plate. For example, Japanese Patent Publication No. 2009-008860 (Patent Document 1) discloses a polarizing plate in which a transparent protective film is laminated on a polarizer via a cured material layer (adhesive layer).

[Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Publication No. 2009-008860

The object of the present invention is to provide a curable composition that can provide an optical laminate having a cured layer composed of a cured product of the curable composition and having good moisture and heat resistance (durability in a high temperature and high humidity environment).

Another object of the present invention is to provide an optical laminate having a cured material layer composed of a cured material of a curable composition and having good moisture and heat resistance, and an image display device including the optical laminate.

The present invention provides a curable composition, an optical laminate, an image display device, and an adhesive composition for a polarizing plate as shown below.

唑啉基的聚合物(A)、及碘化合物(B)。 [1] A hardening composition comprising:

An oxazoline-based polymer (A), and an iodine compound (B).

[2] The curable composition as described in [1] further comprises: at least one selected from the group consisting of a compound (C) having a carboxyl group and an anhydride of the compound (C).

唑啉基的聚合物(A)的

唑啉基與具有羧基的化合物(C)的羧基反應之化合物(D)。 [3] The hardening composition as described in [2] further comprises:

Oxazoline-based polymer (A)

A compound (D) obtained by reacting an oxazoline group with the carboxyl group of a compound (C) having a carboxyl group.

[4] An optical laminate comprising an optical film and a first cured material layer formed of a cured product of the curable composition described in any one of [1] to [3].

[5] The optical laminate as described in [4] comprises the aforementioned optical film, the aforementioned first hardened material layer, and the first thermoplastic resin film in sequence.

[6] The optical laminate as described in [5] comprises, in order, a second thermoplastic resin film, a second cured layer, the optical film, the first cured layer, and the first thermoplastic resin film.

[7] An optical laminate as described in any one of items [4] to [6], wherein the optical film is a polarizer.

[8] An image display device comprising an optical multilayer body as described in any one of items [4] to [7], and an image display element.

唑啉基的聚合物(A)、及碘化合物(B)。 [9] A polarizing plate adhesive composition comprising

An oxazoline-based polymer (A), and an iodine compound (B).

The present invention can provide a curable composition that can provide an optical laminate having a cured layer composed of a cured product of the curable composition and having good moisture and heat resistance.

The present invention can provide an optical laminate having good moisture and heat resistance and including a cured material layer composed of a cured material of a curable composition, and an image display device including the optical laminate.

10: Thermoplastic resin film No. 1

15: First hardened layer

20: Second thermoplastic resin film

25: Second hardened layer

30: Optical film

40: Adhesive layer

Figure 1 is a schematic cross-sectional view showing an example of the optical multilayer body of the present invention.

Figure 2 is a schematic cross-sectional view showing another example of the layered structure of the optical laminate of the present invention.

Figure 3 is a schematic cross-sectional view showing another example of the layered structure of the optical laminate of the present invention.

Figure 4 is a schematic cross-sectional view showing another example of the layer structure of the optical laminate of the present invention.

Figure 5 is a schematic cross-sectional view showing another example of the layered structure of the optical laminate of the present invention.

Figure 6 is a schematic cross-sectional view showing another example of the layer structure of the optical laminate of the present invention.

<Hardening composition>

唑啉基的聚合物(A)、及碘化合物(B)。 The curable composition of the present invention contains

An oxazoline-based polymer (A), and an iodine compound (B).

Hereinafter, the curable composition of the present invention is also referred to as "curable composition (S)". The cured material layer formed by the cured material of the curable composition (S) is also referred to as "first cured material layer".

If the optical laminate contains the first hardened material layer, it can provide an optical laminate having excellent moisture and heat resistance.

唑啉基的聚合物(A) [1]

Oxazoline-based polymer (A)

唑啉基的聚合物(A)係在分子內具有

唑啉基之聚合物，以在側鏈具有

唑啉基之聚合物為佳。 Contains

The oxazoline-based polymer (A) has

Azoline-based polymer having a side chain

Azoline-based polymers are preferred.

唑啉基的聚合物(A)的骨架結構係沒有特別限制，例如能夠包含選自(甲基)丙烯酸骨架、苯乙烯骨架、烯烴骨架、酯骨架、碳酸酯骨架等之1種以上的骨架。 Contains

The skeleton structure of the oxazoline-based polymer (A) is not particularly limited, and may include, for example, one or more skeletons selected from a (meth)acrylic skeleton, a styrene skeleton, an olefin skeleton, an ester skeleton, a carbonate skeleton, and the like.

In this specification, "(meth)acrylic acid" means at least one selected from the group consisting of acrylic acid and methacrylic acid. The same applies to "(meth)acryl" and "(meth)acrylate".

唑啉基的聚合物(A)係可在上述骨架結構的側鏈具有

唑啉基。 Contains

The oxazoline-based polymer (A) may have a

Oxazoline.

唑啉基的聚合物(A)亦可含有在側鏈具有

唑啉基的結構單元(源自含

唑啉基的單體之結構單元)、及不具有

唑啉基的結構單元。 Contains

The oxazoline-containing polymer (A) may also contain a

The structural unit of the oxazoline group (derived from

The structural unit of the monomer of oxazoline group), and does not have

The structural unit of the oxazoline group.

唑啉基的聚合物(A)的較佳一個例子為含

唑啉基的(甲基)丙烯酸系聚合物，該含

唑啉基的(甲基)丙烯酸系聚合物係含有由(甲基)丙烯酸骨架所構成的骨架結構作為結構單元的主成分之共聚合成分，且在側鏈導入有具有

唑啉基的結構單元(源自含

唑啉基的單體之結 構單元)。 Contains

A preferred example of the oxazoline-containing polymer (A) is

A (meth) acrylic polymer containing an oxazoline group, the

The oxazoline-based (meth) acrylic polymer is a copolymer component containing a skeleton structure composed of a (meth) acrylic acid skeleton as a main component of the structural unit, and a (meth) acrylic acid skeleton is introduced into the side chain.

The structural unit of the oxazoline group (derived from

(a structural unit of a monomer containing an oxazoline group).

唑啉基的聚合物(A)，係除了由含

唑啉基的單體共聚合而成者以外，亦可為藉由將聚合物的側鏈官能基改性而使其含有

唑啉基而成者。 As containing

The oxazoline-based polymer (A) is composed of

In addition to being copolymerized with monomers containing oxazoline groups, the side chain functional groups of the polymers may be modified to contain

Oxazoline group.

唑啉基例如可舉出2-

唑啉基、3-

唑啉基、4-

唑啉基等。

唑啉基係較佳為2-

唑啉基等。 As

Examples of the oxazoline group include 2-

Oxazoline, 3-

Oxazoline, 4-

Oxazoline, etc.

The oxazoline group is preferably 2-

Oxazoline, etc.

唑啉基的單體可舉出2-異丙烯基-2-

唑啉、乙烯基-2-

唑啉等。 As the above mentioned

The monomers of oxazoline group include 2-isopropenyl-2-

Oxazoline, vinyl-2-

Oxazoline, etc.

唑啉基的聚合物(A)之重量平均分子量係以5000以上為佳，較佳為10000以上。從提高光學積層體的耐濕熱性、在光學積層體中光學膜與第1硬化物層之間的密著性、第1硬化物層與第1熱塑性樹脂膜之間的密著性的觀點而言，重量平均分子量為上述範圍是有利。 Contains

The weight average molecular weight of the oxazoline-based polymer (A) is preferably 5000 or more, more preferably 10000 or more. The weight average molecular weight within the above range is advantageous from the viewpoint of improving the moisture and heat resistance of the optical laminate, the adhesion between the optical film and the first cured layer in the optical laminate, and the adhesion between the first cured layer and the first thermoplastic resin film.

唑啉基的聚合物(A)的重量平均分子量通常為1000000以下。 Contains

The weight average molecular weight of the oxazoline group polymer (A) is usually 1,000,000 or less.

唑啉基的聚合物(A)的重量平均分子量係能夠以使用凝膠滲透層析法(GPC)而得到的標準聚苯乙烯換算值之方式測定。 Contains

The weight average molecular weight of the oxazoline group-containing polymer (A) can be measured as a standard polystyrene conversion value obtained by gel permeation chromatography (GPC).

唑啉基的聚合物(A)之

唑啉基量(含

唑啉基的聚合物(A)之每1g固形物的

唑啉基的莫耳數)係較佳為0.4mmol/g‧solid以上。

唑啉基量小於上述範圍時，對光學積層體的耐濕熱性為不利。從該觀點而言，含

唑啉基的聚合物之

唑啉基量係較佳為3mmol/g‧solid以上，更佳為5mmol/g‧solid以上且9mmol/g‧solid以下。 Contains

Azoline-based polymer (A)

Azoline base content (including

Per 1g solid content of oxazoline-based polymer (A)

The molar number of the oxazoline group is preferably 0.4 mmol/g‧solid or more.

When the amount of oxazoline groups is less than the above range, it is not favorable for the moisture and heat resistance of the optical laminate.

Azoline-based polymer

The amount of oxazoline groups is preferably 3 mmol/g‧solid or more, more preferably 5 mmol/g‧solid or more and 9 mmol/g‧solid or less.

唑啉基量的上限係沒有特別限制，通常為50mmol/g‧ solid以下。

There is no particular upper limit on the amount of oxazoline groups, but it is usually below 50 mmol/g‧ solid.

唑啉基的聚合物(A)係以水系亦即水溶性聚合物、或水分散性的聚合物為佳。從第1硬化物層的光學特性之觀點而言，含

唑啉基的聚合物(A)係較佳為水溶性聚合物。 Contains

The oxazoline-based polymer (A) is preferably a water-based, i.e., water-soluble, or water-dispersible polymer.

The oxazoline-based polymer (A) is preferably a water-soluble polymer.

唑啉基的聚合物(A)，亦可使用市售品。具體而言，可舉出：日本觸媒股份有限公司製EPOCROSS WS-300、EPOCROSS WS-500、EPOCROSS WS-700(均為商品名)等含

唑啉基的丙烯酸聚合物；日本觸媒股份有限公司製EPOCROSS K-1000 Series、EPOCROSS K-2000 Series、EPOCROSS RPS Series(均為商品名)等含

唑啉基的丙烯酸/苯乙烯聚合物。 As containing

The polymer (A) containing an oxazoline group may be a commercially available product. Specifically, EPOCROSS WS-300, EPOCROSS WS-500, EPOCROSS WS-700 (all trade names) manufactured by Nippon Catalyst Co., Ltd.

Acrylic polymers containing oxazoline; EPOCROSS K-1000 Series, EPOCROSS K-2000 Series, EPOCROSS RPS Series (all trade names) manufactured by Japan Catalyst Co., Ltd.

Oxazoline-based acrylic/styrene polymer.

唑啉基的聚合物(A)係能夠併用2種以上而使用。 Contains

The oxazoline group-based polymer (A) may be used in combination of two or more types.

唑啉基的聚合物(A)係以EPOCROSS WS-300、EPOCROSS WS-500、EPOCROSS WS-700等含

唑啉基的丙烯酸聚合物為佳。 From the viewpoints of the moisture and heat resistance and optical properties of the optical laminate, the adhesion between the optical film and the first cured layer in the optical laminate, the adhesion between the first cured layer and the first thermoplastic resin film, and the water resistance of the first cured layer, the optical laminate having the optical film and the first cured layer has the optical film and the first cured layer having the optical film and the first cured layer has the optical film.

The oxazoline-based polymer (A) is EPOCROSS WS-300, EPOCROSS WS-500, EPOCROSS WS-700, etc.

Azoline-based acrylic polymers are preferred.

唑啉基的聚合物(A)之含量係以5質量%以上且95質量%以下為佳，較佳為10質量%以上且90質量%以下，更佳為20質量%以上且85質量%以下。使含

唑啉基的聚合物(A)之含量成為上述範圍內，從提升光學積層體的耐濕熱性、在光學積層體中光學膜與第1硬化物層之間的密著性、第1硬化物層與第1熱塑性樹脂膜之間的密著性之觀點而言是較佳。 When the solid content of the curable composition (S) is 100% by mass,

The content of the oxazoline group-containing polymer (A) is preferably 5 mass % or more and 95 mass % or less, more preferably 10 mass % or more and 90 mass % or less, and even more preferably 20 mass % or more and 85 mass % or less.

The content of the oxazoline-based polymer (A) within the above range is preferred from the viewpoint of improving the moisture and heat resistance of the optical laminate, the adhesion between the optical film and the first cured layer in the optical laminate, and the adhesion between the first cured layer and the first thermoplastic resin film.

The so-called solid concentration refers to the total concentration of components other than the solvent contained in the curable composition (S).

[2] Iodine compounds (B)

The iodine compound (B) is a compound containing iodine element. The curable composition (S) may contain one iodine compound (B) or two or more iodine compounds (B).

Examples of iodine compounds (B) include the following.

a) Inorganic iodide salts

Iodide alkali metal salts such as lithium iodide, sodium iodide, potassium iodide, cadmium iodide, cesium iodide, etc.; Iodide alkali earth metal salts such as curium iodide, magnesium iodide, calcium iodide, barium iodide, strontium iodide, etc.; Iodide light metal salts or heavy metal salts such as boron iodide, aluminum iodide, zinc iodide, titanium iodide, copper iodide, vanadium iodide, chromium iodide, manganese iodide, nickel iodide, etc.; Ammonium iodide

b) Other inorganic iodine compounds

Iodine (I ₂ ), hydrogen iodide, iodic acid, sodium iodate, potassium iodate, calcium iodate

c) Organic iodide salts

Ammonium salts of iodides such as ammonium iodide, tetraethylammonium iodide, tetrabutylammonium iodide, and ammonium iodate; phosphonium salts of iodides such as tetrabutylphosphine and tetraphenylphosphine; trimethylsulfoxonium iodide; imidazolinium iodide; pyridinium iodide; cobalt iodide

d) Other organic iodine compounds

Iodinated alkyls such as iodinated methyl iodide, iodinated ethyl iodide, iodinated butyl iodide; aromatic iodine compounds such as iodinated naphthalene, iodinated benzene, iodinated benzoic acid, iodinated salicylic acid, iodinated phenol; iodinated acetic acid, iodinated propionic acid, 2-iodobutyric acid, 2-iodo-2-phenylacetic acid

As described later, the curable composition (S) is preferably an aqueous composition. When the curable composition (S) is an aqueous composition, from the perspective of solubility or dispersibility of the composition, the iodine compound (B) is preferably an iodide salt, and more preferably an inorganic iodide salt. For the same reason, the iodine compound (B) is preferably water-soluble.

唑啉基的聚合物(A)100質量份，通常為1質量份以上且300質量份以下，以2質量份以上且250質量份以下為佳，較佳為5質量份以上且200質量份以下，更佳為10質量份以上且180質量份以下，又更佳為10質量份以上且150質量份以下。 From the viewpoint of improving the moisture and heat resistance of the optical laminate, the content of the iodine compound (B) in the curable composition (S) is relatively

The amount of the oxazoline-based polymer (A) is usually 1 part by mass or more and 300 parts by mass or less, preferably 2 parts by mass or more and 250 parts by mass or less, more preferably 5 parts by mass or more and 200 parts by mass or less, more preferably 10 parts by mass or more and 180 parts by mass or less, and even more preferably 10 parts by mass or more and 150 parts by mass or less.

唑啉基的聚合物(A)100質量份，為10質量份以上且160質量份以下，10質量份以上且150質量份以下，10質量份以上且140質量份以下或10質量份以上且120質量份以下。 In one embodiment, the content of the iodine compound (B) is relative to the content of

The amount of the oxazoline group-containing polymer (A) is 10 to 160 parts by mass, 10 to 150 parts by mass, 10 to 140 parts by mass, or 10 to 120 parts by mass, based on 100 parts by mass of the oxazoline group-containing polymer (A).

When the content of the iodine compound (B) is too low, it is difficult to obtain the effect of improving the moisture and heat resistance of the optical laminate by containing the iodine compound (B). In addition, when the content of the iodine compound (B) is too high, at least one of the adhesion between the optical film and the first cured layer and the adhesion between the first cured layer and the first thermoplastic resin film in the optical laminate tends to be easily reduced.

[3] A compound (C) having a carboxyl group and an acid anhydride of the compound (C)

The curable composition (S) may further contain at least one selected from a compound (C) having a carboxyl group and an acid anhydride of the compound (C). Hereinafter, the compound (C) having a carboxyl group is also referred to as "compound (C)".

唑啉基的聚合物(A)的

唑啉基反應的羧基之化合物。在此，所謂羧基亦包含羧基的衍生物，但是不包含化合物(C)的酸酐。 Compound (C) is capable of

Oxazoline-based polymer (A)

The carboxyl compound of the oxazoline group is reactive. Here, the carboxyl group also includes the derivative of the carboxyl group, but does not include the anhydride of the compound (C).

As derivatives of carboxyl groups, carboxylate anions can be cited. As cations of the opposite ions of carboxylate anions, metal ions such as lithium ions, sodium ions, and potassium ions; organic cations such as ammonium ions, cobalt ions, and phosphonium ions, etc.

The curable composition (S) may contain one compound (C) or two or more compounds (C). The curable composition (S) may contain one anhydride of the compound (C) or two or more anhydrides of the compound (C). The curable composition (S) may contain one or more compounds (C) and one or more anhydrides of the compound (C).

In particular, from the viewpoint of improving the moisture and heat resistance of the optical laminate, the adhesion between the optical film and the first cured layer in the optical laminate, the adhesion between the first cured layer and the first thermoplastic resin film, and the water resistance of the first cured layer, the compound (C) is preferably a compound having two or more carboxyl groups (or their derivatives) in the molecule (polyfunctional carboxylic acid compound).

An example of a polyfunctional carboxylic acid compound is a dicarboxylic acid compound. Examples of the dicarboxylic acid compound include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, phthalic acid, isophthalic acid, terephthalic acid, tartaric acid, glutamic acid, apple acid, cis-1,1-dicarboxylic acid, fumaric acid, itaconic acid, muconic acid, 1,4-cyclohexanedicarboxylic acid, 1,4-naphthalene dicarboxylic acid, 2,6-naphthalene dicarboxylic acid, 2,7-naphthalene dicarboxylic acid, 4,4'-biphenyl dicarboxylic acid, 2,5-pyridine dicarboxylic acid, 3,5-pyridine dicarboxylic acid, diphenyl sulfonic acid, diphenyl methane dicarboxylic acid, oxalacetic acid, methyl fumaric acid, 2,6-pyridine dicarboxylic acid, and the like.

Another example of a polyfunctional carboxylic acid compound is a tricarboxylic acid compound. Examples of the tricarboxylic acid compound include citric acid, aconitic acid, propane-1,2,3-tricarboxylic acid, trimellitic acid, 1,3,5-benzenetricarboxylic acid, 1,2,3-benzenetricarboxylic acid (hemimellitic acid), biphenyl-3,4',5-tricarboxylic acid, and 1,3,5-cyclohexanetricarboxylic acid.

Another example of a polyfunctional carboxylic acid compound is a tetracarboxylic acid compound. Examples of the tetracarboxylic acid compound include pyrohexadecene tetracarboxylic acid, diphenyl tetracarboxylic acid, diphenyl ketone tetracarboxylic acid, naphthalene tetracarboxylic acid, thiophene tetracarboxylic acid, butane tetracarboxylic acid, and 1,2,4,5-tetrakis(4-carboxyphenyl)benzene.

In the polyfunctional carboxylic acid compounds exemplified above, at least one carboxyl group may be a derivative thereof.

Compound (C) may also have other functional groups besides the carboxyl group. An example of other functional groups is a hydroxyl group.

From the perspective of the moisture and heat resistance of the optical laminate, the number of carboxyl groups possessed by the compound (C) is preferably 2 or 3.

The polyfunctional carboxylic acid compound may also be a polymer having two or more carboxyl groups (or their derivatives) in the molecule. An example of such a polymer is a carboxyl-modified polymer. An example of a carboxyl-modified polymer is a carboxyl-modified polyvinyl alcohol polymer.

Carboxyl-modified polyvinyl alcohol polymers are polyvinyl alcohol polymers that have been modified by introducing carboxyl groups or their derivatives into the side chains.

As a derivative of the carboxyl group, a carboxylate anion group can be cited. Examples of cations of the counter ions of the carboxylate anion group are as described above. An example of a preferred cation is a sodium ion.

The polyvinyl alcohol polymer constituting the main chain of the carboxyl-modified polyvinyl alcohol polymer may be a vinyl alcohol homopolymer (completely saponified polyvinyl alcohol or partially saponified polyvinyl alcohol) obtained by saponifying polyvinyl acetate, which is a homopolymer of vinyl acetate, or a polyvinyl alcohol copolymer obtained by saponifying a copolymer of vinyl acetate and other monomers copolymerizable therewith.

Other monomers that can be copolymerized with vinyl acetate include unsaturated carboxylic acids, olefins, vinyl ethers, unsaturated sulfonic acids, and (meth)acrylamides having ammonium groups.

The saponification degree of the carboxyl-modified polyvinyl alcohol polymer is usually 80 mol% or more and 100 mol% or less, preferably 85 mol% or more (e.g. 88 mol% or more).

The saponification degree of carboxyl-modified polyvinyl alcohol polymer can be measured according to JIS K 6726:1994.

The degree of modification (modification amount) of the carboxyl-modified polyvinyl alcohol-based polymer by carboxyl groups (or their derivatives) is usually 0.1 mol% or more. From the viewpoint of improving the moisture and heat resistance of the optical laminate, the adhesion between the optical film and the first cured layer in the optical laminate, the adhesion between the first cured layer and the first thermoplastic resin film, and the water resistance of the first cured layer, the degree of modification of the carboxyl-modified polyvinyl alcohol-based polymer is preferably 0.5 mol% or more and 40 mol% or less, and more preferably 1 mol% or more and 20 mol% or less. The degree of modification can be measured, for example, by ¹ H-NMR.

The average degree of polymerization of carboxyl-modified polyvinyl alcohol polymers is usually greater than 100 and less than 3000.

The average degree of polymerization of carboxyl-modified polyvinyl alcohol polymers can be measured in accordance with JIS K 6726:1994.

In a preferred embodiment, the molecular weight of compound (C) is less than 1000. The molecular weight is calculated from the chemical formula, but when compound (C) is a polymer, it can also be a number average molecular weight measured by using a standard polystyrene conversion value obtained by gel permeation chromatography (GPC).

In terms of improving the moisture and heat resistance of the optical laminate, it is advantageous to use a compound (C) with a molecular weight of 1000 or less. From the perspective of the moisture and heat resistance of the optical laminate, the molecular weight of the compound (C) is preferably 800 or less, more preferably 500 or less.

Furthermore, from the viewpoint of the moisture and heat resistance of the optical laminate, the adhesion between the optical film and the first cured layer in the optical laminate, and the adhesion between the first cured layer and the first thermoplastic resin film, the molecular weight of the compound (C) is preferably 90 or more, more preferably 100 or more.

Preferred examples of compound (C) are citric acid, malic acid, maleic acid, and tartaric acid.

As the acid anhydride of compound (C), carboxylic anhydride can be cited. Examples of carboxylic anhydride include acetic anhydride, propionic anhydride, oxalic anhydride, succinic anhydride, maleic anhydride, phthalic anhydride, benzoic anhydride, etc.

唑啉基的聚合物(A)100質量份，以0.01質量份以上且30質量份為佳，較佳為0.1質量份以上且25質量份以下，更佳為0.2質量份以上且20質量份以下，又更佳為0.2質量份以上且15質量份以下，特佳為0.3質量份以上且15質量份 以下。 From the viewpoint of improving the moisture and heat resistance of the optical laminate, the content of at least one selected from the compound (C) and the anhydride of the compound (C) is 2.5% relative to the content of the compound (C).

The amount of the oxazoline-based polymer (A) is preferably 0.01 to 30 parts by mass, more preferably 0.1 to 25 parts by mass, more preferably 0.2 to 20 parts by mass, still more preferably 0.2 to 15 parts by mass, and particularly preferably 0.3 to 15 parts by mass.

唑啉基的聚合物(A)100質量份，為0.3質量份以上且10質量份以下，或為0.5質量份以上且10質量份以下，或為0.5質量份以上且8質量份以下，或為1質量份以上且8質量份以下。 In one embodiment, the content of at least one selected from compound (C) and the anhydride of compound (C) is relative to the content of

The amount of the oxazoline group-containing polymer (A) is 0.3 to 10 parts by mass, or 0.5 to 10 parts by mass, or 0.5 to 8 parts by mass, or 1 to 8 parts by mass, based on 100 parts by mass of the oxazoline group-containing polymer (A).

When the content of at least one selected from compound (C) and the anhydride of compound (C) is too small, it is difficult to obtain the effect of improving the moisture-heat resistance of the optical laminate. On the other hand, when the content of at least one selected from compound (C) and the anhydride of compound (C) is too large, the effect of improving the moisture-heat resistance of the optical laminate tends to be reduced.

唑啉基的聚合物(A)之

唑啉基與具有羧基的化合物(C)的羧基反應之化合物(D) [4] Promote

Azoline-based polymer (A)

Compound (D) obtained by reacting an oxazoline group with the carboxyl group of a compound (C) having a carboxyl group

唑啉基的聚合物(A)之

唑啉基與具有羧基的化合物(C)的羧基反應之化合物(D)。以下，將該化合物亦稱為「化合物(D)」。在此所稱之促進亦包含使該反應開始之情況。 The hardening composition (S) may further contain:

Azoline-based polymer (A)

A compound (D) in which an oxazoline group reacts with a carboxyl group of a compound (C) having a carboxyl group. Hereinafter, the compound is also referred to as "compound (D)". The term "promotion" as used herein also includes the case of initiating the reaction.

When the curable composition (S) contains the acid anhydride of the compound (C), the compound (D) starts to react with the carboxyl group in the carboxylic acid generated by hydrolysis of at least a part of the acid anhydride of the compound (C) to start or promote the reaction.

唑啉基的聚合物(A)的

唑啉基、與化合物(C)的羧基及/或化合物(C)的酸酐因水解而產生的羧基反應之觸媒的功能之化合物。 Preferred examples of compound (D) include acid compounds.

Oxazoline-based polymer (A)

A compound having a catalyst function for the reaction between an oxazoline group and a carboxyl group of the compound (C) and/or a carboxyl group generated by hydrolysis of an acid anhydride of the compound (C).

Examples of the above-mentioned acid compounds include inorganic acids such as sulfuric acid, hydrogen chloride, nitric acid, phosphoric acid, phosphorous acid, and boric acid; and organic acids such as p-toluenesulfonic acid, dodecylbenzenesulfonic acid, naphthalenesulfonic acid, methanesulfonic acid, benzenesulfonic acid, phenylphosphoric acid, p-aminobenzenesulfonic acid (sulfanilic acid), phenylphosphonic acid, acetic acid, and propionic acid.

The curable composition (S) may contain one compound (D) or two or more compounds (D).

The compound (D) can also be formulated in the curable composition (S) in the form of a solution (e.g., aqueous solution) containing the compound (D).

In particular, from the perspective of improving the moisture and heat resistance of the optical laminate, the adhesion between the optical film and the first cured layer in the optical laminate, and the adhesion between the first cured layer and the first thermoplastic resin film, the compound (D) is preferably a stronger acid. Examples of such acid compounds include sulfuric acid, hydrochloric acid, nitric acid, and p-toluenesulfonic acid.

When a strong acid such as the above is used as compound (D), it tends to improve the adhesion between the optical film and the first cured layer, and the adhesion between the first cured layer and the first thermoplastic resin film in the optical laminate.

唑啉基的聚合物(A)100質量份，通常為1質量份以上且150質量份以下，從提高光學積層體的耐濕熱性、在光學積層體中光學膜與第1硬化物層之間的密著性、第1硬化物層與第1熱塑性樹脂膜之間的密著性之觀點而言，係以3質量份以上且100質量份以下為佳，較佳為5質量份以上且100質量份以下，更佳為10質量份以上且100質量份以下。 The content of the compound (D) in the curable composition (S) is relative to the content of

The amount of the oxazoline-based polymer (A) is 100 parts by mass, and is usually 1 part by mass or more and 150 parts by mass or less. From the viewpoint of improving the moisture and heat resistance of the optical laminate, the adhesion between the optical film and the first cured layer in the optical laminate, and the adhesion between the first cured layer and the first thermoplastic resin film, it is preferably 3 parts by mass or more and 100 parts by mass or less, more preferably 5 parts by mass or more and 100 parts by mass or less, and even more preferably 10 parts by mass or more and 100 parts by mass or less.

唑啉基的聚合物(A)100質量份，為10質量份以上且80質量份以下或10質量份以上且50質量份以下。 In a preferred embodiment, from the viewpoint of improving the moisture and heat resistance of the optical laminate, the content of the compound (D) is

The amount of the oxazoline group-containing polymer (A) is 10 parts by mass or more and 80 parts by mass or more, or 10 parts by mass or more and 50 parts by mass or less, based on 100 parts by mass of the oxazoline group-containing polymer (A).

When the content of compound (D) is too small, it is difficult to obtain the effect of improving the moisture and heat resistance of the optical laminate by containing compound (D). Moreover, when the content of compound (D) is too small, it is difficult to obtain the effect of improving the adhesion between the optical film and the first cured layer of the optical laminate, and the effect of improving the adhesion between the first cured layer and the first thermoplastic resin film by containing compound (D).

When the content of compound (D) is too high, at least one of the adhesion between the optical film and the first cured layer and the adhesion between the first cured layer and the first thermoplastic resin film in the optical laminate tends to be reduced.

[5] Other ingredients

唑啉基的聚合物(A)、碘化合物(B)、化合物(C)、化合物(C)的酸酐及化合物(D)以外之其它成分。 The hardening composition (S) may contain

The other components except the oxazoline-based polymer (A), the iodine compound (B), the compound (C), the anhydride of the compound (C) and the compound (D).

Other components include: polyaldehydes, melamine compounds, zirconium oxide compounds, iodine compounds, aziridine compounds, glyoxal, glyoxal derivatives, water-soluble epoxy resins and other curing components and crosslinking agents; modified polyvinyl alcohol polymers other than carboxyl-modified polyvinyl alcohol polymers; coupling agents, adhesion agents, antioxidants, ultraviolet absorbers, heat stabilizers, anti-hydrolysis agents and other additives.

The curable composition (S) may contain one or more other components.

The curable composition (S) preferably contains a solvent. Examples of the solvent include water, an organic solvent, or a mixture thereof. The solvent preferably contains water, but water and a water-soluble organic solvent may also be used together. Examples of the organic solvent include alcohol solvents such as ethanol and 1-methoxy-2-propanol.

The main component of the solvent is preferably water. The so-called main component means that it accounts for more than 50% by mass of the total solvent.

The solid content of the curable composition (S) is usually 0.5% by mass or more and 20% by mass or less, preferably 1% by mass or more and 15% by mass or less.

The curable composition (S) can be used as a coating liquid for forming a coating film (coating layer) on a substrate. For example, the coating film can be formed by applying the curable composition (S) on the substrate and curing the coating layer. The substrate is preferably an optical film. The optical film is described below. At this time, the optical laminate includes an optical film and a first cured layer composed of a cured product of the curable composition (S).

The curable composition (S) can also be used as an adhesive composition. In one embodiment, the curable composition (S) is an adhesive composition for bonding the optical film to the first thermoplastic resin film. In this case, the optical laminate includes the optical film, the first cured material layer (adhesive layer) composed of the cured material of the curable composition (S), and the first thermoplastic resin film in sequence. The optical laminate can be manufactured by coating a curable composition (S) on the bonding surface of at least one of the optical film and the first thermoplastic resin film, laminating the optical film and the first thermoplastic resin film via the coating layer to obtain a laminate, and then curing the coating layer.

The optical laminate is preferably a polarizing plate with an optical film as a polarizer. The so-called polarizing plate is an optical laminate including a polarizer and a first hardened layer (a hardened layer composed of a hardened material of a hardening composition (S)) stacked on at least one side thereof.

The curable composition (S) of the adhesive composition is preferably an adhesive composition for polarizing plates, that is, an adhesive composition for manufacturing polarizing plates. In this case, the curable composition (S) is used, for example, to bond the polarizing plate to the first thermoplastic resin film.

The curable composition (S) is preferably a water-based composition. That is, the curable composition (S) is preferably a solution in which the formulation components are dissolved in a solvent containing water, or a dispersion (e.g., an emulsion) in which the formulation components are dispersed in a solvent containing water.

The viscosity of the curable composition (S) at 25°C is preferably below 50mPa‧sec, more preferably above 1mPa‧sec and below 30mPa‧sec, and even more preferably above 2mPa‧sec and below 20mPa‧sec. When the viscosity at 25°C is greater than 50mPa‧sec, it is difficult to apply evenly and there is a possibility of uneven application, and there is a possibility of blockage of the holes in the piping and other undesirable conditions.

The viscosity of the curable composition (S) at 25°C can be measured using an E-type viscometer.

<Optical layered structure>

The optical laminate of the present invention comprises an optical film and a first cured layer (a cured layer composed of a cured product of a curable composition (S)) laminated on at least one side thereof.

According to the present invention, since the cured material layer contained in the optical laminate is composed of a cured material of the curable composition (S), the moisture and heat resistance of the optical laminate can be improved.

[1] Composition of optical laminates

Examples of the layer structure of optical laminates are shown in Figures 1 to 5.

The optical laminate shown in FIG. 1 includes an optical film 30 and a first hardened layer 15 stacked on one surface thereof. The first hardened layer 15 can function as a protective layer for covering and protecting the surface of the optical film 30 and as an optical functional layer for adding optical functions to the optical film 30.

It is preferred that the optical film 30 and the first hardened layer 15 are in direct contact.

The optical laminate shown in FIG. 2 includes an optical film 30 and a first thermoplastic resin film 10 laminated on one side of the optical film 30 via a first curing layer 15. The first curing layer 15 can function as an adhesive layer that connects the optical film 30 to the first thermoplastic resin film 10.

It is preferred that the first hardened material layer 15 and the first thermoplastic resin film 10 are in direct contact.

It is preferred that the optical film 30 and the first hardened layer 15 are in direct contact.

The optical laminate shown in FIG. 3 includes an optical film 30, a first thermoplastic resin film 10 laminated on one side of the optical film 30 via a first curing layer 15, and a second thermoplastic resin film 20 laminated on the other side of the optical film 30 via a second curing layer 25. That is, the optical laminate of the present invention may also include the second thermoplastic resin film 20, the second curing layer 25, the optical film 30, the first curing layer 15, and the first thermoplastic resin film 10 in sequence. The first cured layer 15 and the second cured layer 25 can function as an adhesive layer for bonding the optical film 30 to the first thermoplastic resin film 10 and as an adhesive layer for bonding the optical film 30 to the second thermoplastic resin film 20, respectively.

It is preferred that the first hardened material layer 15 and the first thermoplastic resin film 10 are in direct contact.

It is preferred that the optical film 30 and the first hardened layer 15 are in direct contact.

It is preferred that the second hardened material layer 25 and the second thermoplastic resin film 20 are in direct contact.

It is preferred that the optical film 30 and the second hardened layer 25 are in direct contact.

The optical laminate shown in FIG. 4 includes an optical film 30, a first cured layer 15 laminated on one side thereof, and a second thermoplastic resin film 20 laminated on the other side of the optical film 30 via a second cured layer 25. The first cured layer 15 can function as a protective layer for covering and protecting the surface of the optical film 30, and as an optical functional layer for adding an optical function to the optical film 30. The second cured layer 25 can function as an adhesive layer for bonding the optical film 30 to the second thermoplastic resin film 20.

It is preferred that the optical film 30 and the first hardened layer 15 are in direct contact.

It is preferred that the second hardened material layer 25 and the second thermoplastic resin film 20 are in direct contact.

It is preferred that the optical film 30 and the second hardened layer 25 are in direct contact.

The optical laminate shown in FIG. 5 includes an optical film 30, a first cured layer 15 deposited on one side thereof, and a second cured layer 25 deposited on the other side of the optical film 30. The first cured layer 15 and the second cured layer 25 can function as a protective layer for covering and protecting the surface of the optical film 30, and as an optical functional layer for adding optical functions to the optical film 30.

It is preferred that the optical film 30 and the first hardened layer 15 are in direct contact.

It is preferred that the optical film 30 and the second hardened layer 25 are in direct contact.

The optical film 30 may also be various optical films (thin films with optical properties) that can be assembled in image display devices such as liquid crystal display devices. Examples of the optical film 30 include polarizers, phase difference films, brightness enhancement films, anti-glare films, anti-reflection films, diffusion films, and light-gathering films.

The optical laminate can include other layers (or films) other than those mentioned above. Examples of other layers include: an adhesive layer deposited on the outer surface of the first thermoplastic resin film 10, the second thermoplastic resin film 20, the first hardened layer 15, the second hardened layer 25, and/or the optical film 30; a separator film (also called a "peeling film") deposited on the outer surface of the adhesive layer; a separator film deposited on the outer surface of the first thermoplastic resin film 10, the second thermoplastic resin film 20, the first hardened layer 15, the second hardened layer 25, and/or the optical film 30; A protective film (also referred to as a "surface protective film") on the outer surface of the cured layer 15, the second cured layer 25 and/or the optical film 30; an optical functional film (or layer) laminated on the outer surface of the first thermoplastic resin film 10, the second thermoplastic resin film 20, the first cured layer 15, the second cured layer 25 and/or the optical film 30 via a bonding agent layer and an adhesive layer, etc.

[2] Polarizer

Polarizer is a layer or film that has the function of selectively transmitting linear polarized light from a certain direction of natural light.

As a polarizer, for example, a film formed by adsorbing/aligning a dichroic pigment on a polyvinyl alcohol resin film can be cited. As a dichroic pigment, iodine, dichroic organic dyes, etc. can be cited.

In addition, the polarizer can also be a coated polarizing film formed by coating a dichroic dye in a lyotropic liquid crystal state on a substrate film and aligning/fixing it.

The above polarizers are called absorption polarizers because they selectively transmit linear polarized light from a certain direction of natural light and absorb linear polarized light from another direction.

The polarizer is not limited to an absorption type polarizer, and may also be a reflection type polarizer that selectively transmits linear polarization from a certain direction of natural light and reflects linear polarization from another direction, or a scattering type polarizer that scatters linear polarization from another direction. However, in terms of excellent viewing, an absorption type polarizer is preferred. In particular, a polyvinyl alcohol polarizing film composed of a polyvinyl alcohol resin film is preferred, and a polyvinyl alcohol polarizing film formed by adsorbing/aligning dichroic pigments such as iodine and dichroic dyes on the polyvinyl alcohol resin film is more preferred, and a polyvinyl alcohol polarizing film formed by adsorbing/aligning iodine on the polyvinyl alcohol resin film is particularly preferred.

As the polyvinyl alcohol resin, a polyvinyl acetate resin obtained by saponification can be used. As for the polyvinyl acetate resin, in addition to polyvinyl acetate which is a homopolymer of vinyl acetate, copolymers of vinyl acetate and other monomers copolymerizable with the vinyl acetate can also be cited. Other monomers copolymerizable with vinyl acetate include unsaturated carboxylic acids, olefins, vinyl ethers, unsaturated sulfonic acids, and (meth)acrylamides having an ammonium group, etc.

The saponification degree of polyvinyl alcohol resin is usually 85 mol% or more and 100 mol% or less, preferably 98 mol% or more. Polyvinyl alcohol resin can also be modified, for example, aldehyde-modified polyvinyl formaldehyde or polyvinyl acetal can be used. The average polymerization degree of polyvinyl alcohol resin is usually 1000 or more and 10000 or less, preferably 1500 or more and 5000 or less.

The average degree of polymerization of polyvinyl alcohol-based resins can be obtained according to JIS K 6726:1994.

The film formed by such a polyvinyl alcohol resin is used as a raw film of a polarizing film composed of a polyvinyl alcohol resin film. The method of forming a polyvinyl alcohol resin film is not particularly limited, and a well-known method can be adopted. The thickness of the polyvinyl alcohol raw film is, for example, less than 150 μm, preferably less than 100 μm (for example, less than 50 μm) and more than 5 μm.

The polarizing film composed of a polyvinyl alcohol resin film can be manufactured by a well-known method. Specifically, it can be manufactured by a method comprising the following steps: a step of uniaxially stretching the polyvinyl alcohol resin film; a step of dyeing the polyvinyl alcohol resin film with a dichroic dye to adsorb the dichroic dye; a step of treating the polyvinyl alcohol resin film adsorbed with the dichroic dye with a boric acid aqueous solution (crosslinking treatment); and, after the treatment, a step of washing with a boric acid aqueous solution.

The thickness of the polarizer can be set to 40 μm or less, preferably 30 μm or less (e.g., 20 μm or less, preferably 15 μm or less, and more preferably 10 μm or less or 8 μm or less). By using the method described in Japanese Patent Publication No. 2000-338329 or Japanese Patent Publication No. 2012-159778, it is easier to manufacture a thin film polarizer, and it is easier to make the thickness of the polarizer e.g., 20 μm or less, preferably 15 μm or less, and more preferably 10 μm or less or 8 μm or less. The thickness of the polarizer is usually 2 μm or more. Reducing the thickness of the polarizer is beneficial to the thinning of the optical laminate (polarizing plate) and the image display device including the optical laminate.

[3] Phase difference film

Examples of phase difference films include: stretched films formed by uniaxially or biaxially stretching a light-transmitting thermoplastic resin; films formed by aligning and fixing liquid crystal compounds such as discotic liquid crystals or nematic liquid crystals; and films having the above-mentioned liquid crystal layer formed on a substrate film. In addition, in this specification, phase difference films also include zero hysteresis films.

The substrate film is usually a film made of a thermoplastic resin. An example of the thermoplastic resin is a cellulose ester resin such as cellulose triacetate.

Examples of the light-transmitting thermoplastic resin include the resin constituting the first thermoplastic resin film 10 described later.

The so-called zero hysteresis film refers to a film with an in-plane phase difference _Re and a thickness direction phase difference _Rth of -15 to 15nm. The phase difference film is suitable for use in IPS mode liquid crystal display devices. The in-plane phase difference _Re and the thickness direction phase difference _Rth are preferably both -10 to 10nm, and more preferably -5 to 5nm. Here, the in-plane phase difference _Re and the thickness direction phase difference _Rth are values at a wavelength of 590nm.

The in-plane phase difference value _Re and the thickness direction phase difference value _Rth are defined by the following formulas: _Re = ( _nx - _ny ) × d

_Rth =[( _nx + _ny )/2- _nz ]×d

Where _nx is the refractive index in the slow axis direction (x-axis direction) within the film plane, _ny is the refractive index in the fast axis direction (y-axis direction orthogonal to the x-axis within the plane), _nz is the refractive index in the thickness direction (z-axis direction perpendicular to the film plane), and d is the film thickness.

Zero hysteresis film is a resin film composed of, for example, cellulose resin, chain polyolefin resin, cyclic polyolefin resin, etc., polyethylene terephthalate resin, or (meth) acrylic resin. In particular, cellulose resin, polyolefin resin, or (meth) acrylic resin is suitable because it is easy to control the phase difference value and is also easy to obtain.

As thin films that show optical anisotropy by coating/alignment of liquid crystal compounds, the following thin films can be cited: first form: phase difference film in which rod-shaped liquid crystal compounds are aligned in a direction horizontal to the supporting substrate, second form: phase difference film in which rod-shaped liquid crystal compounds are aligned in a direction perpendicular to the supporting substrate, third form: phase difference film in which rod-shaped liquid crystal compounds change their alignment direction in a spiral shape within the plane, fourth form: phase difference film in which disc-shaped liquid crystal compounds are aligned in a tilted direction, fifth form: biaxial phase difference film in which disc-shaped liquid crystal compounds are aligned in a direction perpendicular to the supporting substrate.

For example, as an optical film used in an organic electroluminescent display, the first form, the second form, and the fifth form are suitable. Alternatively, they can be layered and used.

When the phase difference film is a layer composed of polymers of polymerizable liquid crystal compounds in an aligned state (hereinafter, sometimes referred to as "optically anisotropic layer"), the phase difference film preferably has reverse wavelength dispersion. The so-called reverse wavelength dispersion is an optical property that the phase difference value in the plane of liquid crystal alignment at a short wavelength is smaller than the phase difference value in the plane of liquid crystal alignment at a long wavelength. It is preferred that the phase difference film satisfies the following formula (1) and formula (2). In addition, _Re (λ) represents the in-plane phase difference value relative to light of wavelength λnm.

_Re (450)/ _Re (550)≦1 (1)

1≦ _Re (630)/ _Re (550) (2)

When the retardation film is in the first form and has reverse wavelength dispersion, coloring is reduced when the display device is on a black screen, which is preferred. In formula (1), 0.82≦R _e (450)/R _e (550)≦0.93 is preferred, and 120≦R _e (550)≦150 is more preferred.

As polymerizable liquid crystal compounds when the phase difference film is a thin film having an optically anisotropic layer, there can be cited compounds having a polymerizable group among the compounds described in "3.8.6 Network (Completely Crosslinked Type)" and "6.5.1 Liquid Crystal Material b. Polymerizable Nematic Liquid Crystal Material" in the Liquid Crystal Handbook (Edited by Liquid Crystal Handbook Editorial Committee, published by Maruzen Co., Ltd. on October 30, 2001), and compounds described in Japanese Patent Application Laid-Open No. Polymerizable liquid crystal compounds described in Japanese Patent Publication No. 2010-31223, Japanese Patent Publication No. 2010-270108, Japanese Patent Publication No. 2011-6360, Japanese Patent Publication No. 2011-207765, Japanese Patent Publication No. 2016-81035, International Publication No. 2017/043438, and Japanese Patent Table No. 2011-207765.

The method of manufacturing a phase difference film from a polymer in an aligned state of a polymerizable liquid crystal compound can be exemplified by the method described in Japanese Patent Publication No. 2010-31223.

In the second form, the in-plane phase difference value _Re (550) can be adjusted within the range of 0 to 10 nm, preferably within the range of 0 to 5 nm, and the thickness direction phase difference value R _th can be adjusted within the range of -10 to -300 nm, preferably within the range of -20 to -200 nm.

The thickness direction retardation value R _th , which means the refractive index anisotropy in the thickness direction, can be calculated from the retardation value R ₅₀ measured by tilting the in-plane fast axis by 50 degrees to the tilt axis and the in-plane retardation value _Re . That is, the thickness direction retardation value R _th can be calculated by obtaining n x , ny and nz from the in-plane retardation value _Re , the retardation value R ₅₀ measured by tilting the fast axis by 50 degrees to the tilt axis, the thickness d of the retardation film, and the average refractive index n ₀ of the retardation film according to the following equations ( ₄ ) to (6 ₎ , and substituting _{these n x , ny} and _nz into equation (3).

R _th =[(n _x +n _y )/2-n _z ]×d (3)

_Re =( _nx - _ny )×d (4)

R ₅₀ =(n _x -n _y ')×d/cos(φ) (5)

(n _x +n _y +n _z )/3=n ₀ (6)

Here, φ=sin ^-1 〔sin(40°)/n ₀ 〕

n _y '=n _y ×n _z /〔n _y ² ×sin ² (φ)+n _z ² ×cos ² (φ)〕 ^1/2

The phase difference film may also be a multi-layer film having two or more layers. For example, a protective film is laminated on one or both sides of the phase difference film; and a phase difference film is laminated with two or more layers of phase difference films separated by an adhesive or bonding agent.

[4] First hardened layer

The first hardened material layer 15 is a hardened material layer composed of a hardened material of a hardening composition (S). The hardening composition (S) is as described above. The hardening composition (S) can be hardened, for example, by heat.

[5] Thermoplastic resin film

The first thermoplastic resin film 10 and the second thermoplastic resin film 20 can be thin films respectively made of: light-transmitting (preferably optically transparent) thermoplastic resins, such as polyolefin resins such as chain polyolefin resins (polypropylene resins, etc.) and cyclic polyolefin resins (norbornene resins, etc.); cellulose ester resins such as cellulose triacetate and cellulose diacetate; polyester resins such as polyethylene terephthalate, polyethylene naphthalate, and polybutylene terephthalate; polycarbonate resins; (meth) acrylic resins; polystyrene resins; or mixtures and copolymers of these resins.

The first thermoplastic resin film 10 and the second thermoplastic resin film 20 can each be an unstretched film, or a uniaxially or biaxially stretched film. Biaxial stretching can be simultaneous biaxial stretching in two stretching directions at the same time, or can be sequential biaxial stretching in which the film is stretched in a first direction and then stretched in a different second direction.

The first thermoplastic resin film 10 and/or the second thermoplastic resin film 20 may also be a protective film that plays a role in protecting the optical film 30, and may also be a protective film that also has optical functions such as a phase difference film.

Regarding the phase difference film, the above-mentioned description [4] is cited.

Examples of chain polyolefin resins include homopolymers of chain olefins such as polyethylene resin and polypropylene resin, and copolymers composed of two or more chain olefins.

Cyclic polyolefin resins are a general term for resins containing cyclic alkenes as polymerized units, with norbornene, tetracyclododecene (also known as dimethano octahydronaphthalene) or their derivatives as representative examples. Examples of cyclic polyolefin resins include ring-opening (co)polymers of cyclic alkenes and their hydrogenates, addition polymers of cyclic alkenes, copolymers of cyclic alkenes with chain alkenes such as ethylene and propylene or aromatic compounds having a vinyl group, and modified (co)polymers of these polymers modified with unsaturated carboxylic acids or their derivatives.

In particular, it is suitable to use a norbornene resin having norbornene monomers such as norbornene and polycyclic norbornene monomers as the cyclic olefin.

Cellulose ester resins are resins in which at least a portion of the hydroxyl groups in cellulose are esterified with acetic acid, or they may be mixed esters in which a portion is esterified with acetic acid and a portion is esterified with other acids. Cellulose ester resins are preferably cellulose acetate resins.

Examples of cellulose acetate resins include cellulose triacetate, cellulose diacetate, cellulose acetate propionate, and cellulose acetate butyrate.

Polyester resins are resins other than the above-mentioned cellulose ester resins that have ester bonds, and are usually composed of polycondensates of polycarboxylic acids or their derivatives and polyols.

Examples of polyester resins include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polytrimethylene terephthalate, polytrimethylene naphthalate, polycyclohexane dimethyl terephthalate, and polycyclohexane dimethyl naphthalate.

In particular, from the perspectives of mechanical properties, solvent resistance, scratch resistance, and cost, polyethylene terephthalate is suitable for use. Polyethylene terephthalate refers to a resin in which more than 80 mol% of the repeating units are composed of ethylene terephthalate, and may also contain structural units derived from other copolymer components (dicarboxylic acid components such as isophthalic acid; glycol components such as propylene glycol, etc.).

Polycarbonate resins are polyesters formed from carbonic acid and diols or bisphenols. From the perspective of heat resistance, weather resistance, and acid resistance, aromatic polycarbonates with diphenylalkane in the molecular chain are particularly suitable.

Examples of polycarbonates include polycarbonates derived from bisphenols such as 2,2-bis(4-hydroxyphenyl)propane (also known as bisphenol A), 2,2-bis(4-hydroxyphenyl)butane, 1,1-bis(4-hydroxyphenyl)cyclohexane, 1,1-bis(4-hydroxyphenyl)isobutane, and 1,1-bis(4-hydroxyphenyl)ethane.

(Meth)acrylic resins are polymers containing structural units derived from (meth)acrylic monomers. Examples of (meth)acrylic monomers include methacrylate and acrylate.

Examples of methacrylates include methyl methacrylate, ethyl methacrylate, n-butyl, iso-butyl or tert-butyl methacrylate, cyclohexyl methacrylate, phenyl methacrylate, benzyl methacrylate, 2-ethylhexyl methacrylate, 2-hydroxyethyl methacrylate, and the like.

Examples of acrylates include ethyl acrylate, n-butyl, iso-butyl or tert-butyl acrylate, cyclohexyl acrylate, phenyl acrylate, benzyl acrylate, 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, etc.

(Meth) acrylic resins may be polymers composed only of structural units derived from (meth) acrylic acid monomers, or may contain other structural units.

In a preferred embodiment, the (meth) acrylic resin contains methyl methacrylate as a copolymer component, or contains methyl methacrylate and methyl acrylate as copolymer components.

In a preferred embodiment, the (meth) acrylic resin can be a polymer having methacrylate as the main monomer (containing 50% by mass or more), preferably a copolymer obtained by copolymerizing methacrylate with other copolymer components.

The glass transition temperature of (meth)acrylic resin is preferably above 80°C and below 160°C. The glass transition temperature can be controlled by adjusting the polymerization ratio of methacrylate monomers and acrylate monomers, the carbon chain length of each ester group and the type of functional groups possessed by these monomers, and the polymerization ratio of multifunctional monomers relative to the total monomers.

As a means to increase the glass transition temperature of (meth) acrylic resin, it is also effective to introduce a ring structure into the main chain of the polymer. The ring structure is preferably a mixed ring structure such as a cyclic anhydride structure, a cyclic imide structure, and a lactone structure. Specifically, there can be cited: cyclic anhydride structures such as glutaric anhydride structure and succinic anhydride structure; cyclic imide structures such as glutarimide structure and succinimide structure; lactone ring structures such as butyrolactone and valerolactone.

As the content of the ring structure in the main chain increases, the glass transition temperature of the (meth)acrylic resin tends to increase.

The cyclic anhydride structure and cyclic imide structure can be introduced by the following methods: a method of introducing by copolymerizing monomers having a cyclic structure such as maleic anhydride and maleic imide; a method of introducing a cyclic anhydride structure by dehydration/demethylation condensation reaction after polymerization; and a method of introducing a cyclic imide structure by reacting an amino compound, etc.

The resin (polymer) having a lactone ring structure can be obtained by the following method: after preparing a polymer having a hydroxyl group and an ester group in the polymer chain, the hydroxyl group and the ester group in the obtained polymer are subjected to cyclocondensation by heating and optionally in the presence of a catalyst such as an organic phosphorus compound to form a lactone ring structure.

The (meth)acrylic resin and the thermoplastic resin film formed by the (meth)acrylic resin may also contain additives as needed. Examples of additives include lubricants, anti-caking agents, heat stabilizers, antioxidants, antistatic agents, light-resistant agents, impact resistance improvers, surfactants, etc.

These additives can also be used as a thermoplastic resin constituting a thermoplastic resin film when using a thermoplastic resin other than a (meth)acrylic resin.

From the perspective of film forming properties and impact resistance of the film, (meth) acrylic resins may also contain acrylic rubber particles as an impact modifier. The so-called acrylic rubber particles are particles that have an elastic polymer with acrylate as the main component as an essential component. They can be single-layer structures that are essentially composed of the elastic polymer alone, or multi-layer structures that have the elastic polymer as one layer.

Examples of the above-mentioned elastic polymer include crosslinked elastic copolymers obtained by copolymerizing alkyl acrylate as a main component with other vinyl monomers and crosslinking monomers that can copolymerize with the alkyl acrylate.

Alkyl acrylates as the main component of the elastic polymer include methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, etc., whose alkyl groups have carbon numbers of 1 or more and 8 or less. Alkyl acrylates having alkyl groups of 4 or more carbon numbers are suitable.

As other vinyl monomers that can be copolymerized with the above-mentioned alkyl acrylates, compounds having one polymerizable carbon-carbon double bond in the molecule can be cited, more specifically: methacrylates such as methyl methacrylate; aromatic vinyl compounds such as styrene; vinyl cyanide compounds such as acrylonitrile, etc.

As the above-mentioned crosslinking monomer, crosslinking compounds having at least two polymerizable carbon-carbon double bonds in the molecule can be cited, and more specifically, (meth)acrylates of polyols such as ethylene glycol di(meth)acrylate and butanediol di(meth)acrylate; (meth)acrylate esters such as allyl (meth)acrylate; divinylbenzene, etc. can be cited.

A laminate of a film made of (meth)acrylic resin without rubber particles and a film made of (meth)acrylic resin containing rubber particles can be used as a thermoplastic resin film to be bonded to the optical film 30. In addition, a (meth)acrylic resin layer formed on one or both sides of a phase difference display layer made of a resin different from (meth)acrylic resin and showing phase difference can be used as a thermoplastic resin film to be bonded to the optical film 30.

The first thermoplastic resin film 10 and the second thermoplastic resin film 20 are preferably films containing at least one thermoplastic resin selected from the group consisting of cellulose ester resins, polyester resins, (meth) acrylic resins and cyclic polyolefin resins, and preferably cellulose ester resin films, polyester resin films, (meth) acrylic resin films or cyclic polyolefin resin films.

The first thermoplastic resin film 10 and/or the second thermoplastic resin film 20 may also contain ultraviolet absorbers, infrared absorbers, organic dyes, pigments, inorganic pigments, antioxidants, antistatic agents, surfactants, lubricants, dispersants, thermal stabilizers, etc. When the optical multilayer body is applied to an image display device, by arranging the thermoplastic resin film containing ultraviolet absorbers on the viewing side of the image display element (such as a liquid crystal unit, an organic EL display element, etc.), the image display element can be inhibited from being degraded by ultraviolet rays.

Examples of ultraviolet absorbers include salicylate compounds, diphenyl ketone compounds, benzotriazole compounds, cyanoacrylate compounds, and nickel cerium salt compounds.

The first thermoplastic resin film 10 and the second thermoplastic resin film 20 may be films made of the same thermoplastic resin or different thermoplastic resins. The first thermoplastic resin film 10 and the second thermoplastic resin film 20 may be the same or different in thickness, presence or absence of additives and their types, phase difference characteristics, etc.

The first thermoplastic resin film 10 and/or the second thermoplastic resin film 20 may also have a surface treatment layer (coating layer) such as a hard coating layer, an anti-glare layer, an anti-reflection layer, a light diffusion layer, an antistatic layer, an antifouling layer, a conductive layer, etc. on its outer surface (the surface opposite to the optical film 30).

The thickness of the first thermoplastic resin film 10 and the second thermoplastic resin film 20 is usually 5 μm or more and 200 μm or less, preferably 10 μm or more and 120 μm or less, more preferably 10 μm or more and 85 μm or less, and more preferably 15 μm or more and 65 μm or less. The thickness of the first thermoplastic resin film 10 and the second thermoplastic resin film 20 can be 50 μm or less, or 40 μm or less. Reducing the thickness of the first thermoplastic resin film 10 and the second thermoplastic resin film 20 is beneficial to the thinning of the optical laminate (polarizing plate) and the image display device including the optical laminate.

From the perspective of improving adhesion, the surfaces of the first thermoplastic resin film 10 and the second thermoplastic resin film 20 to be coated with the curable composition can be subjected to surface modification treatments such as saponification treatment, plasma treatment, corona treatment, and primer treatment. From the perspective of simplifying the steps, surface modification treatment can also be performed. The bonding surface of the optical film 30 can also be subjected to surface modification treatment to replace the bonding surface of the thermoplastic resin film, or the bonding surface of the thermoplastic resin film and the bonding surface of the optical film 30 can be subjected to surface modification treatment together.

When the first thermoplastic resin film 10 or the second thermoplastic resin film 20 is a cellulose ester resin film, it is preferable to perform a saponification treatment from the viewpoint of improving adhesion. As a saponification treatment, a method of immersing in an alkaline aqueous solution such as sodium hydroxide and potassium hydroxide can be cited.

[6] Second hardened layer

The curable composition forming the second cured layer 25 may be the above-mentioned curable composition (S) or another curable composition different therefrom. From the perspective of the moisture and heat resistance of the optical laminate, the second cured layer 25 is preferably a cured layer of the curable composition (S).

When the first hardened material layer 15 and the second hardened material layer 25 are formed of hardening compositions (S), the hardening compositions may be of the same composition or of different compositions.

As other curable compositions, there can be cited well-known water-based compositions (containing water-based adhesives) containing curable resin components dissolved or dispersed in water and well-known active energy ray-curable compositions (containing active energy ray-curable adhesives) containing active energy ray-curable compounds, etc.

Examples of the resin component contained in the water-based composition include polyvinyl alcohol-based resins, urethane resins, and the like.

In order to improve adhesion and bonding, the water-based composition containing polyvinyl alcohol resin can further contain hardening components or crosslinking agents such as polyaldehydes, melamine compounds, zirconium oxide compounds, iodine compounds, glyoxal, glyoxal derivatives, and water-soluble epoxy resins.

As an aqueous composition containing urethane resin, there can be cited an aqueous composition containing polyester-based ionic polymer type urethane resin and a compound having a glycidoxy group. The so-called polyester-based ionic polymer type urethane resin is a urethane resin having a polyester skeleton and into which a small amount of ionic components (hydrophilic components) are introduced.

The active energy ray-curable composition is a composition that is cured by irradiation with active energy rays such as ultraviolet rays, visible light, electron rays, and X-rays. When the active energy ray-curable composition is used, the second cured layer 25 is a cured layer of the composition.

The active energy ray-curable composition can be a composition containing an epoxy compound that cures by cationic polymerization as a curable component, preferably a UV-curable composition containing such an epoxy compound as a curable component. The so-called epoxy compound means a compound having an average of more than one, preferably more than two epoxy groups in the molecule. Only one epoxy compound may be used or two or more epoxy compounds may be used in combination.

Examples of epoxy compounds include: hydrogenated epoxy compounds (epoxypropyl ethers of polyols having an alicyclic ring) obtained by reacting an alicyclic polyol obtained by hydrogenating the aromatic ring of an aromatic polyol with epichlorohydrin; aliphatic epoxy compounds such as polyepoxypropyl ethers of aliphatic polyols or epoxide adducts thereof; and epoxy compounds having one or more epoxy groups bonded to an alicyclic ring in the molecule, i.e., alicyclic epoxy compounds, etc.

The active energy ray-curable composition may contain a radically polymerizable (meth)acrylic compound as a curable component in place of the above-mentioned epoxy compound, or contain the epoxy compound and a radically polymerizable (meth)acrylic compound as a curable component. Examples of (meth)acrylic compounds include: (meth)acrylic ester monomers having one or more (meth)acrylic ester groups in the molecule; and (meth)acrylic ester oligomers having at least two (meth)acrylic ester groups in the molecule obtained by reacting two or more functional group-containing compounds.

When the active energy ray-curable composition contains an epoxy compound that cures by cationic polymerization as a curable component, it is preferable to contain a photocationic polymerization initiator. Examples of photocationic polymerization initiators include: aromatic diazonium salts; aromatic iodonium salts, aromatic stibnium salts, etc.; iron-aromatic hydrocarbon complexes, etc.

When the active energy ray-curable composition contains a radical polymerizable component such as a (meth) acrylic acid compound, it is preferable to contain a photoradical polymerization initiator. Examples of the photoradical polymerization initiator include acetophenone-based initiators, diphenyl ketone-based initiators, benzoin ether-based initiators, thioxanthrone-based initiators, oxanthrone, fluorenone, camphorquinone, benzaldehyde, anthraquinone, etc.

The optical laminate may also contain an adhesive layer instead of the second cured layer 25. That is, the optical film 30 may be bonded to the second thermoplastic resin film 20 via the adhesive layer. The adhesive layer is described below.

[7] Fabrication of optical laminates

By laminating the first thermoplastic resin film 10 on one side of the optical film 30 via the first curing layer 15, the optical laminate having the structure shown in FIG. 2 can be obtained, and by further laminating the second thermoplastic resin film 20 on the other side of the optical film 30 via the second curing layer 25, the optical laminate having the structure shown in FIG. 3 can be obtained.

When manufacturing an optical laminate having both the first thermoplastic resin film 10 and the second thermoplastic resin film 20, the films can be layered one side at a time in stages, or the films can be layered on both sides at the same time.

As a method for bonding the optical film 30 to the first thermoplastic resin film 10, a method of applying a curable composition (S) to one or both of the bonding surfaces of the optical film 30 and the first thermoplastic resin film 10, laminating it on the bonding surface of the other, and bonding them by pressing from top to bottom using, for example, a bonding roller.

The curable composition (S) can be applied by various coating methods such as a doctor blade, a wire rod, a die-stitch coating machine, a notch wheel coating machine, a gravure coating machine, etc. Alternatively, the optical film 30 and the first thermoplastic resin film 10 may be continuously supplied with the bonding surface of the two facing inward, and the curable composition (S) may be cast between them.

After the optical film 30 and the first thermoplastic resin film 10 are bonded together, it is preferred to heat the laminate including the optical film 30, the first curing layer 15 and the first thermoplastic resin film 10. The temperature of the heat treatment is, for example, above 40°C and below 100°C, preferably above 50°C and below 90°C. The heat treatment can remove the solvent contained in the curable composition layer. Moreover, the heat treatment can cause the curable composition to undergo a curing/crosslinking reaction.

The above bonding method can also be applied to the bonding of the optical film 30 and the second thermoplastic resin film 20.

When an active energy ray-curable composition is used as the curable composition constituting the second curable layer, the curable composition layer is dried as necessary and then irradiated with active energy rays to cure the curable composition layer.

The light source used for irradiating active energy rays can be any light source that can generate ultraviolet rays, electron rays, X-rays, etc. Particularly suitable are those with luminescence distribution below 400nm, such as low-pressure mercury lamps, medium-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, chemical lamps, black light lamps, microwave-excited mercury lamps, and halogenated metal lamps.

As shown in FIG. 1, an optical laminate having no first thermoplastic resin film on the first curing layer 15 can be manufactured by applying a curable composition (S) on the surface of an optical film 30 and subjecting the obtained laminate to a heat treatment at 80°C for 300 seconds, for example, using a hot air dryer. In addition, after manufacturing a laminate consisting of a separator film/curable composition (S)/optical film 30, the optical laminate shown in FIG. 1 can also be manufactured by peeling off the separator film and then subjecting the laminate to a heat treatment.

The thickness of the first hardened layer 15 formed by the hardening composition (S) is, for example, 1 nm or more and 20 μm or less, preferably 5 nm or more and 10 μm or less, more preferably 10 nm or more and 5 μm or less, and even more preferably 20 nm or more and 1 μm or less. The hardened layer formed by the above-mentioned well-known aqueous composition can also have the same thickness.

The thickness of the hardened layer formed by the active energy ray-hardening composition is, for example, greater than 10 nm and less than 20 μm, preferably greater than 100 nm and less than 10 μm, and more preferably greater than 500 nm and less than 5 μm.

The thickness of the first hardened layer 15 and the second hardened layer 25 may be the same or different.

[8]Other components of optical multilayers

[8-1]Optical functional films

In addition to the optical film 30 (such as a polarizer) that is used to impart the required optical function, the optical laminate can also have other optical functional films, a preferred example of which is a phase difference film.

As described above, the first thermoplastic resin film 10 and/or the second thermoplastic resin film 20 can also serve as a phase difference film, but these films can also be laminated with a phase difference film. In the latter case, the phase difference film can be laminated on the outer surface of the first thermoplastic resin film 10, the second thermoplastic resin film 20, the first cured layer 15 and/or the second cured layer 25 via an adhesive layer or a bonding agent layer. The description of the phase difference film is cited from the above [4].

Examples of other optical functional films (optical components) that may be contained in optical laminates such as polarizing plates include focusing plates, brightness enhancement films, reflective layers (reflective films), semi-transmissive reflective layers (semi-transmissive reflective films), light diffusion layers (light diffusion films), etc.

The focusing plate is used for the purpose of light path control, etc. It can be a prism array sheet, a lens array sheet, a sheet with spots, etc.

Brightness enhancement films are used to enhance the brightness of image display devices that use optical laminates such as polarizing plates. Specifically, they include: reflective polarizing separation sheets designed to produce anisotropy in reflectivity by stacking multiple thin films with different refractive indices; and circular polarizing separation sheets formed by supporting an alignment film of cholesterol-type liquid crystal polymer or its alignment liquid crystal layer on a substrate film, etc.

The reflective layer, semi-transmissive reflective layer, and light diffusion layer are respectively used to set the polarizer as a reflective, semi-transmissive, or diffusion optical component. The reflective polarizer is used in a liquid crystal display device that reflects incident light from the viewing side and displays it. Since the light source such as the backlight can be omitted, it is easy to make the liquid crystal display device thinner. The semi-transmissive polarizer is used in a liquid crystal display device that is reflective in bright places and uses light from the backlight to display in dark places. In addition, the diffusion polarizer is used in a liquid crystal display device that gives light diffusion properties to suppress display defects such as moire. The reflective layer, semi-transmissive reflective layer, and light diffusion layer can be formed using well-known methods.

[8-2] Adhesive layer

The optical multilayer body can contain an adhesive layer. The adhesive layer may be an adhesive layer for bonding the optical multilayer body to a liquid crystal unit, an organic EL display element or other image display element, or other optical components. The adhesive layer can be deposited on the outer surface of the optical film 30 in the optical laminate shown in FIGS. 1 and 2, can be deposited on the outer surface of the first thermoplastic resin film 10 or the second thermoplastic resin film 20 in the optical laminate shown in FIG. 3, can be deposited on the outer surface of the first hardened layer 15 or the second thermoplastic resin film 20 in the optical laminate shown in FIG. 4, and can be deposited on the outer surface of the first hardened layer 15 or the second hardened layer 25 in the optical laminate shown in FIG. 5.

FIG6 shows an example of an adhesive layer 40 being deposited on the outer surface of the second thermoplastic resin film 20 of the optical laminate shown in FIG3.

As the adhesive used in the adhesive layer, (meth)acrylic resins, silicone resins, polyester resins, polyurethane resins, polyether resins, etc. can be used as base polymers. In particular, (meth)acrylic adhesives are preferred from the perspectives of transparency, adhesion, reliability, weather resistance, heat resistance, reprocessability, etc.

In the (meth)acrylic adhesive, a (meth)acrylic acid alkyl ester having an alkyl group with a carbon number of 20 or less, such as methyl, ethyl, n-, iso- or t-butyl, and a (meth)acrylic acid monomer containing a functional group, such as (meth)acrylic acid and (meth)ethyl hydroxyacrylate, is preferably prepared so that the glass transition temperature is below 25°C, more preferably below 0°C, to obtain a (meth)acrylic resin with a weight average molecular weight of 100,000 or more, which is suitable for use as a base polymer.

The adhesive layer can be formed on the optical laminate by the following methods: for example, dissolving or dispersing the adhesive composition in an organic solvent such as toluene or ethyl acetate to prepare an adhesive liquid, and directly applying the adhesive liquid on the target surface of the optical laminate to form the adhesive layer; and forming the adhesive layer into a thin sheet on a release film that has been subjected to a mold release treatment, and transferring it to the target surface of the optical laminate, etc.

The thickness of the adhesive layer is determined according to its adhesion, etc., and is preferably in the range of 1μm or more and 50μm or less, and more preferably in the range of 2μm or more and 40μm or less.

The optical laminate can include the above-mentioned isolation film. The isolation film can be a film made of polyethylene resins such as polyethylene, polypropylene resins such as polypropylene, polyester resins such as polyethylene terephthalate, etc. In particular, a stretched film of polyethylene terephthalate is preferred.

The adhesive layer may contain fillers composed of glass fibers, glass beads, resin beads, metal powders, other inorganic powders, pigments, colorants, antioxidants, ultraviolet absorbers, antistatic agents, etc. as needed.

[8-3] Protective film

The optical laminate can contain a protective film for protecting its surface (typically the surface of the first thermoplastic resin film 10, the second thermoplastic resin film 20, the first hardened layer 15 and/or the second hardened layer 25). The protective film is, for example, removed together with the adhesive layer after the optical laminate is bonded to an image display device or other optical components.

The protective film is composed of, for example, a substrate film and an adhesive layer deposited on the substrate film. The above description is used for the adhesive layer.

The resin constituting the substrate film is a thermoplastic resin such as polyethylene resin such as polyethylene, polypropylene resin such as polypropylene, polyester resin such as polyethylene terephthalate or polyethylene naphthalate, polycarbonate resin, etc. Polyester resin such as polyethylene terephthalate is preferred.

<Image display device>

The optical multilayer body of the present invention can be applied to an image display device. In this case, the image display device includes an optical multilayer body and an image display element. As the image display element, a liquid crystal unit, an organic EL display element, etc. can be cited. As for such image display elements, previously known ones can be used.

When the optical laminate of the polarizing plate is applied to a liquid crystal display device, the optical laminate can be arranged on the backlight side (back side) of the liquid crystal unit, or on the viewing side, or on both the back side and the viewing side. When the optical laminate of the polarizing plate is applied to an organic EL display device, the optical laminate is usually arranged on the viewing side of the organic EL display element.

[Implementation example]

The following discloses examples to more specifically describe the present invention, but the present invention is not limited to these examples. In the examples, the % and parts indicating the content or usage amount are based on the quality standard unless otherwise specified.

唑啉基的聚合物(A)、碘化合物(B)、具有羧基的化合物(C)、及促進含

唑啉基的聚合物(A)的

唑啉基與化合物(C)的羧基反應之化合物(D)，係各自簡記為(A)、(B)、(C)、(D)。 In Table 1,

A polymer containing an oxazoline group (A), an iodine compound (B), a compound having a carboxyl group (C), and a catalyst containing

Oxazoline-based polymer (A)

The compound (D) obtained by reacting the oxazoline group with the carboxyl group of the compound (C) are abbreviated as (A), (B), (C), and (D), respectively.

(Manufacturing example: manufacturing of polarizer)

A 60μm thick polyvinyl alcohol film (average degree of polymerization: about 2,400, saponification degree: 99.9 mol% or more) was immersed in 30°C pure water, and then immersed in a 30°C aqueous solution with a mass ratio of iodine/potassium iodide/water of 0.02/2/100. Subsequently, it was immersed in a 56.5°C aqueous solution with a mass ratio of potassium iodide/boric acid/water of 12/5/100. Then, after washing with 8°C pure water, it was dried at 65°C to obtain a 23μm thick polarizer with iodine adsorption alignment on the polyvinyl alcohol film. The stretching was mainly carried out in the steps of iodine dyeing and boric acid treatment, and the total stretching ratio was 5.5 times.

<Implementation Examples 1 to 6, Comparative Example 1>

(1) Preparation of hardening composition

The components shown in Table 1 were mixed with pure water as a solvent in the amounts shown in Table 1 to prepare a curable composition (aqueous adhesive solution). The units of the amounts of the components shown in Table 1 are parts by mass, and the amounts of the components are amounts converted to solids. In Example 1, the concentration of (A) in the obtained curable composition was set to 4.0% by mass, the concentration of (A) in Example 2 was set to 5.0% by mass, the concentration of (A) in Example 3 was set to 6.0% by mass, the concentration of (A) in Examples 4 and 5 was set to 7.0% by mass, and the concentration of (A) in Example 6 was set to 5.0% by mass. In Comparative Example 1, the concentration of (X) in the curable composition is set to 3.0 mass %.

(2) Manufacturing of polarizing plates

After saponification treatment was applied to one side of a triacetate cellulose (TAC) film [trade name "KC4UAW" manufactured by Konica Minolta Opto Co., Ltd., thickness: 40 μm], the curable composition prepared in the above (1) was applied to the saponification-treated side using a bar coater, and at the same time, a zero retardation film composed of a cyclic polyolefin resin [trade name "ZEONOR" manufactured by ZEON Co., Ltd., thickness: 23 μm] was subjected to a corona treatment, and the curable composition prepared in the above (1) was applied to the corona-treated side using a bar coater. The TAC film layer that has been saponified is deposited on one side of the polarizer and the zero phase difference film layer that has been corona treated is deposited on the other side so that the curable composition becomes the polarizer side, thereby obtaining a laminate having a layer structure of zero phase difference film/curable composition layer/polarizer/curable composition layer/TAC film. The laminate is heated at 80°C for 300 seconds using a hot air dryer to manufacture a polarizing plate having a layer structure of zero phase difference film/cured layer/polarizer/cured layer/TAC film. The thickness of each cured layer in the manufactured polarizing plate is 20 to 60nm.

(3) Evaluation of optical durability (moisture and heat resistance)

After cutting the obtained polarizing plate into a size of 30 mm × 30 mm, the zero phase difference film side was bonded to the glass substrate via a (meth) acrylic adhesive to obtain a test sample. The layer structure of the test sample is glass substrate/(meth) acrylic adhesive layer/zero phase difference film/cured layer/polarizer/cured layer/TAC film. The glass substrate used is an alkali-free glass substrate [trade name "Eagle XG" manufactured by Corning].

The obtained measurement sample was measured for MD transmittance and TD transmittance in the wavelength range of 380 to 780 nm using a spectrophotometer with an integrating sphere [product name "V7100" manufactured by JASCO Corporation], and the polarization degree at each wavelength was calculated. The calculated polarization degree was corrected for the luminescence factor using the 2 degree area (C light source) of JIS Z 8701:1999 "Methods of expressing colors - _XYZ colorimetric system and _{X10Y10Z10 colorimetric} system" to obtain the luminescence factor corrected polarization degree Py before the moisture and heat resistance test. The measurement sample was mounted on the spectrophotometer with an integrating sphere in such a manner that the TAC film side of the polarizing plate was used as the detection side and light was incident from the glass substrate side.

Polarization degree (%) is defined by the following formula: Polarization degree 100×(Tp(λ)-Tc(λ))/(Tp(λ)+Tc(λ)).

Tp(λ) is the transmittance (%) of the test sample measured under the relationship between linear polarization and parallel polarization of incident wavelength λ(nm).

Tc(λ) is the transmittance (%) of the test sample measured under the relationship between linear polarization and orthogonal polarization of incident wavelength λ(nm).

Next, the test sample was placed in a high temperature and high humidity environment of 85°C and 85%RH for 500 hours, and then placed in an environment of 23°C and 50%RH for 24 hours for a moisture and heat resistance test. After the moisture and heat resistance test, the luminescence factor correction polarization degree Py was obtained by the same method as before the moisture and heat resistance test.

Calculate the absolute value of the difference between the luminous factor correction luminance Py after the heat and humidity resistance test and the luminous factor correction luminance Py before the heat and humidity resistance test (｜△Py｜).

Next, from the obtained |△Py| value, the "△Py change rate" (%) of each example based on the |△Py| of Comparative Example 1 was calculated according to the following formula. The calculated values of the △Py change rate are shown in Table 1. The larger the △Py change rate, the better the moisture and heat resistance.

The △Py change rate of each example (%) = 100 × | {(｜△Py｜ of each example) - (｜△Py｜ of Comparative Example 1) } | / (｜△Py｜ of Comparative Example 1) Moreover, in any of the embodiments and comparative examples, △Py shows a negative value.

The detailed information of each component shown in Table 1 is as follows.

唑啉基作為側鏈之含

唑啉基的丙烯酸系聚合物的水溶液、固形物濃度：10質量%、

唑啉價(理論值)：130g solid/eq.、

唑啉基量(理論值)：7.7mmol/g,solid、數量平均分子量：4×10⁴、重量平均分子量：12×10⁴)] a1: EPOCROSS WS-300 manufactured by Japan Catalyst Co., Ltd. [with 2-

Oxazoline as a side chain

Aqueous solution of oxazoline-based acrylic acid polymer, solid concentration: 10% by mass

Oxazoline value (theoretical value): 130g solid/eq.

Azoline group content (theoretical value): 7.7mmol/g, solid, number average molecular weight: 4×10 ⁴ , weight average molecular weight: 12×10 ⁴ )]

b1: Zinc iodide (ZnI ₂ )

b2: Titanium iodide (TiI ₄ )

c1: citric acid

d1: sulfuric acid

x1: "Gohsefimer Z-200" manufactured by Nippon Synthetic Chemical Industry Co., Ltd. [acetyl acetyl modified polyvinyl alcohol, average degree of polymerization: 1100, saponification degree: 98.5 mol% or more]

y1: Glyoxal

<Implementation Examples 7 to 11>

(1) Preparation of curable composition

The components shown in Table 2 are mixed with pure water as a solvent in the amounts shown in Table 2 to prepare a hardening composition (adhesive aqueous solution). The units of the amounts of each component shown in Table 2 are parts by mass, and the amounts of each component are converted into solid forms. The concentration of (A) in the hardening composition obtained in Example 7 is set to 8.0% by mass, the concentration of (A) in the hardening composition of Examples 8 and 10 is set to 5.0% by mass, and the concentration of (A) in the hardening composition of Examples 9 and 11 is set to 7.0% by mass.

(2) Production of polarizing plates

After saponification treatment was applied to one side of a triacetate cellulose (TAC) film [Konical Minolta Opto Co., Ltd., trade name "KC4UAW", thickness: 40 μm], the curable composition prepared in the above-mentioned (1) was applied to the saponification-treated side using a bar coater. At the same time, a zero-retardation film composed of a cyclic polyolefin resin [ZEONOR, Nippon Zeon Co., Ltd., trade name "ZEONOR", thickness: 23 μm] was applied to one side of the film, and the curable composition prepared in the above-mentioned (1) was applied to the corona-treated side using a bar coater. The TAC film layer that has been saponified is deposited on one side of the polarizer and the zero phase difference film layer that has been corona treated is deposited on the other side so that the curable component layer becomes the polarizer side, thereby obtaining a laminate having a layer structure of zero phase difference film/curable component layer/polarizer/curable component layer/TAC film. The laminate is heated at 80°C for 300 seconds using a hot air dryer to manufacture a polarizing plate having a layer structure of zero phase difference film/curable layer/polarizer/curable layer/TAC film. The thickness of each cured layer in the manufactured polarizing plate is 20 to 60nm.

(3) Evaluation of optical durability (moisture and heat resistance)

After cutting the obtained polarizing plate into a size of 30mm×30mm, the zero phase difference film side was bonded to a glass substrate via a (meth) acrylic adhesive to obtain a test sample. The layer structure of the test sample is glass substrate/(meth) acrylic adhesive layer/zero phase difference film/cured layer/polarizer/cured layer/TAC film. The glass substrate used is an alkali-free glass substrate [Corning's product name "Eagle XG"].

The obtained measurement sample was measured using a spectrophotometer with an integrating sphere (product name "V7100" manufactured by JASCO Corporation) to measure the MD transmittance and TD transmittance in the wavelength range of 380 to 780 nm, and the polarization degree of each wavelength was calculated. The calculated polarization degree was corrected for the luminescence factor in the 2-degree area (C light source) of JIS Z ₈₇₀₁ :1999 "Color display method - XYZ colorimetric system and _{X10Y10Z10 colorimetric} system" to obtain the luminescence factor corrected polarization degree Py before the moisture and heat resistance test. In addition, the measurement sample was mounted on the spectrophotometer with an integrating sphere in such a way that the TAC film side of the polarizing plate was used as the tester side and the light was incident from the glass substrate side.

Polarization degree (%) is defined by the following formula: Polarization degree (λ) = 100 × (Tp (λ) - Tc (λ)) / (Tp (λ) + Tc (λ)).

Tp(λ) is the transmittance (%) of the test sample measured under the relationship between linear polarization and parallel polarization of incident wavelength λ(nm).

Tc(λ) is the transmittance (%) of the test sample measured under the relationship between linear polarization and orthogonal polarization of incident wavelength λ(nm).

Then, the test sample was placed in a high temperature and high humidity environment of 85°C and 85%RH for 500 hours, and then placed in an environment of 23°C and 50%RH for 24 hours for moisture and heat resistance test. After the moisture and heat resistance test, the luminous factor correction polarization degree Py was obtained by the same method as before the moisture and heat resistance test.

Calculate the absolute value of the difference between the luminous factor-corrected polarization degree Py after the moisture and heat resistance test and the luminous factor-corrected polarization degree Py before the moisture and heat resistance test (｜△Py｜).

Next, from the obtained |△Py| value, the "△Py change rate" (%) of each example based on the |△Py| of Comparative Example 1 was calculated according to the following formula. The calculated values of the △Py change rate are shown in Table 2. The larger the △Py change rate, the better the moisture and heat resistance.

The △Py change rate of each case (%) = 100×｜{(｜△Py of each case｜)-(｜△Py of comparison case 1｜)}｜/(｜△Py of comparison case 1｜)

The details of each ingredient shown in Table 2 are as follows.

唑啉基作為側鏈之含

唑啉基的丙烯酸系聚合物的水溶液、固形物濃度：10質量%、

唑啉價(理論值)：130g solid/eq.、

唑啉基量(理論值)： 7.7mmol/g,solid、數量平均分子量：4×10⁴、重量平均分子量：12×10⁴)〕 a1: Epocros WS-300 manufactured by Japan Catalyst Co., Ltd.

Oxazoline as a side chain

Aqueous solution of oxazoline-based acrylic acid polymer, solid concentration: 10% by mass

Oxazoline value (theoretical value): 130g solid/eq.

Amount of oxazoline group (theoretical value): 7.7mmol/g, solid, number average molecular weight: 4×10 ⁴ , weight average molecular weight: 12×10 ⁴ )〕

b1: Zinc iodide (ZnI ₂ )

b3: cesium iodide

b4: Ammonium iodide

c1: citric acid

d1: sulfuric acid

15‧‧‧The first hardened layer

30‧‧‧Optical film

Claims (9)

A hardening composition comprising

A polymer containing oxazoline (A), and an iodine compound (B), wherein the content of the iodine compound (B) is relative to the content of

The amount of the oxazoline-based polymer (A) is 100 parts by mass, 1 part by mass or more and 300 parts by mass or less, and the iodine compound (B) is at least one selected from the group consisting of alkali metal iodide, alkali earth metal iodide, boron iodide, aluminum iodide, zinc iodide, titanium iodide, copper iodide, vanadium iodide, chromium iodide, manganese iodide and nickel iodide. The curable composition as described in Item 1 of the patent application further contains: at least one selected from the group consisting of a compound (C) having a carboxyl group and an acid anhydride of the compound (C). The hardening composition as described in item 2 of the patent application further comprises:

Oxazoline-based polymer (A)

A compound (D) obtained by reacting an oxazoline group with the carboxyl group of a compound (C) having a carboxyl group. An optical laminate includes an optical film and a first hardened material layer composed of a hardened material of a hardening composition described in any one of items 1 to 3 of the patent application scope. The optical laminate as described in Item 4 of the patent application scope includes the aforementioned optical film, the aforementioned first hardened material layer, and the first thermoplastic resin film in sequence. The optical laminate as described in Item 5 of the patent application scope comprises, in sequence, a second thermoplastic resin film, a second hardened material layer, the aforementioned optical film, the aforementioned first hardened material layer, and the aforementioned first thermoplastic resin film. An optical laminate as described in any one of items 4 to 6 of the patent application, wherein the optical film is a polarizer. An image display device includes an optical multilayer body as described in any one of items 4 to 7 of the patent application scope, and an image display element. A polarizing plate adhesive composition comprising

A polymer containing oxazoline (A), and an iodine compound (B), wherein the content of the iodine compound (B) is relative to the content of

The amount of the oxazoline-based polymer (A) is 100 parts by mass, 1 part by mass or more and 300 parts by mass or less, and the iodine compound (B) is at least one selected from the group consisting of alkali metal iodide, alkali earth metal iodide, boron iodide, aluminum iodide, zinc iodide, titanium iodide, copper iodide, vanadium iodide, chromium iodide, manganese iodide and nickel iodide.

Images