TW201800526A - Optical member having adhesive layer - Google Patents

Abstract

The present invention aims at an optical member having an adhesive layer that exhibits high adhesion to liquid crystal cells and the like, and can be easily peeled off right after being joined. The present invention provides an optical member having an adhesive layer, including an optical member, and an adhesive layer laminated on the optical member. After the optical member having an adhesive layer is laminated on an alkali-free glass plate via the adhesive layer and stored for 24 hours at a temperature of 23 DEG C, a peeling force between the optical member having the adhesive layer and the alkali-free glass is set as P23. Also, after the optical member having an adhesive layer is laminated on an alkali-free glass plate via the adhesive layer and stored for 48 hours at a temperature of 50 DEG C, a peeling force between the optical member having the adhesive layer and the alkali-free glass is set as P50. Thus, a ratio of the P50 and P23 (P50/P23) is 4.5 or more.

Description

Optical member with adhesive layer

The invention relates to an optical component with a pressure-sensitive adhesive layer.

A polarizing plate formed by laminating a protective film on one or both sides of a polarizer is widely used as an optical member of an image display device such as a liquid crystal display device, an organic electroluminescence (organic EL) display device, etc. In recent years, it has been widely used in optical components of various mobile devices such as mobile phones, smart phones, and tablet terminal devices. Optical members such as polarizing plates are laminated with an adhesive layer thereon to form an optical member with an adhesive layer, and are mostly used by, for example, bonding to a liquid crystal cell of a liquid crystal display device [for example, refer to Patent Document 1] .

Such an optical member with an adhesive layer is required to exhibit high adhesion after being adhered to a liquid crystal cell or the like. On the other hand, when there is a poor adhesion to the liquid crystal cell or the like, it is required to be able to peel off immediately and easily.

[Prior technical literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2010-066755

However, a conventional optical member with an adhesive layer that exhibits adhesion to a liquid crystal cell or the like exhibits high adhesion immediately after bonding, and is not easily peeled from the liquid crystal cell or the like even after bonding.

An object of the present invention is to provide an optical member with an adhesive layer that can exhibit high adhesion to liquid crystal cells and the like and can be easily peeled off immediately after bonding.

This invention provides the optical member with an adhesive layer shown below.

[1] An optical member with an adhesive layer includes an optical member and an adhesive layer laminated on the optical member, wherein the optical member with the adhesive layer is: when the optical member is to pass through the adhesive layer The peeling force between the above-mentioned optical member with an adhesive layer and the alkali-free glass after being laminated on an alkali-free glass plate and stored in an environment at a temperature of 23 ° C. for 24 hours is set to be P ₂₃ . When the peel force between the above-mentioned optical member with an adhesive layer and the alkali-free glass laminated on an alkali-free glass plate and stored at 50 ° C. for 48 hours is set to P ₅₀ , the above-mentioned P ₅₀ and the above-mentioned P ₂₃ The ratio (P ₅₀ / P ₂₃ ) is 4.5 or more.

The aforementioned P ₂₃ is usually 0.5 N / 25 mm or more.

The pressure-sensitive adhesive layer may be, for example, a constituent unit containing a (meth) acrylic monomer derived from a hydroxyl group, and the content of the constituent unit is The layer composed of the adhesive composition of the (meth) acrylic resin (A) of 3.5% by weight or less may be a layer of the (meth) acrylic resin (A) containing the constituent unit content of more than 3.5% by weight. A layer composed of an adhesive composition.

This adhesive composition contains a crosslinking catalyst (C-1) and an alkoxy group-containing compound (C-2), and may further contain an isocyanate-based crosslinking agent (B-1). This adhesive composition may further contain an ionic compound (D). This adhesive composition may further contain a silane compound (E).

The present invention also provides the following adhesive composition.

[2] An adhesive composition formed on a first film made of a cyclic polyolefin resin in a layered state, and a state in which a first alkali-free glass plate is laminated on the formed first layer The peeling force between the first layer and the first alkali-free glass plate after storage for 24 hours at 23 ° C is set to P _CO23 , and it is molded on a second film made of a cyclic polyolefin resin. Layered, peeling between the second layer and the second alkali-free glass plate after the second alkali-free glass plate is laminated on the formed second layer and stored at 50 ° C for 48 hours. when force is set to _P CO50, with the above-described _P CO50 _P CO23 the ratio of _(P CO50 / P CO23) of 4.5 or more.

According to the present invention, it is possible to provide an optical member with an adhesive layer that can exhibit high adhesion to liquid crystal cells and the like at a high temperature and can be easily peeled off immediately after bonding.

1‧‧‧Polarizer

2‧‧‧ surface treatment layer

3, 4‧‧‧ protective film

7‧‧‧ retardation film

8‧‧‧ interlayer adhesive

10‧‧‧ polarizing plate

20‧‧‧ Adhesive layer

25‧‧‧ polarizing plate with adhesive layer

30‧‧‧ glass substrate

FIG. 1 shows an optical member with an adhesive layer of the present invention. A schematic cross-sectional view of the example.

Fig. 2 is a schematic cross-sectional view showing another example of the optical member with an adhesive layer of the present invention.

Fig. 3 is a schematic sectional view showing still another example of the optical member with an adhesive layer of the present invention.

Fig. 4 is a schematic sectional view showing still another example of the optical member with an adhesive layer of the present invention.

The adhesive layer constituting the optical member with an adhesive layer of the present invention is composed of, for example, an adhesive composition containing a (meth) acrylic resin (A), wherein the (meth) acrylic resin (A) It contains structural units derived from a (meth) acrylic monomer having a hydroxyl group.

<Adhesive composition>

[1] (meth) acrylic resin (A)

The (meth) acrylic resin (A) is a polymer containing as a main component a constituent unit derived from a (meth) acrylic acid ester represented by the following formula (I):

The polymer which further contains the structural unit derived from the (meth) acrylic monomer which has a hydroxyl group is preferable. In this specification, "(meth) acrylic acid" means acrylic acid and / or methacrylic acid. "(Meth)" also has the same meaning in the case of methacrylic acid ester.

In the above formula (I), R ¹ represents a hydrogen atom or a methyl-based, R ² represents an alkyl group may be substituted Department alkoxy of 1 to 10 carbon atoms having 1 to 14 carbon, or carbon may also be An alkoxy group having 1 to 10 substituted aralkyl groups having 7 to 21 carbon atoms. R ² is preferably an alkyl group having 1 to 14 carbon atoms which may be substituted by an alkoxy group having 1 to 10 carbon atoms.

Examples of the (meth) acrylate represented by formula (I) include alkyl (meth) acrylate, and specific examples thereof include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, ( Alkyl parts such as n-propyl (meth) acrylate, n-butyl (meth) acrylate, n-octyl (meth) acrylate, and lauryl (meth) acrylate are linear alkyl (meth) acrylates; For example, isopropyl (meth) acrylate, isobutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, etc. Group) alkyl acrylate and the like. The carbon number of the alkyl portion in the alkyl (meth) acrylate is preferably from 1 to 8, more preferably from 1 to 6.

When R ² is an alkyl group substituted with an alkoxy group, that is, a specific example of the (meth) acrylate represented by the formula (I) when R ² is an alkoxy alkyl group, the (meth) acrylic acid 2 is included. -Methoxyethyl, ethoxymethyl (meth) acrylate, and the like. The carbon number of the alkyl group in the alkoxyalkyl group is preferably from 1 to 8, and more preferably from 1 to 6. The carbon number of the alkoxy group in the alkoxyalkyl group is preferably from 1 to 8, and more preferably from 1 to 4. Specific examples of the (meth) acrylate represented by the formula (I) when R ² is an aralkyl group having 7 to 21 carbon atoms include benzyl (meth) acrylate and the like. The carbon number of the aralkyl group is preferably 7 to 11.

(Meth) acrylate represented by formula (I) can be used alone 1 You can use 2 or more types together. In particular, the (meth) acrylate is preferably an alkyl (meth) acrylate, more preferably an alkyl acrylate, and even more preferably n-butyl acrylate. The (meth) acrylic resin (A) is preferably a constitutional unit derived from n-butyl acrylate in a total constitutional unit constituting the constitutional unit. It goes without saying that, in addition to n-butyl acrylate, a (meth) acrylate represented by the formula (I) can also be used in combination.

The content of the constitutional unit derived from the (meth) acrylic acid ester represented by formula (I) is usually 60% by weight or more and less than 100% by weight in the total constitutional unit constituting the (meth) acrylic resin (A). It is preferably 70 to 99.9% by weight, and more preferably 80 to 99.6% by weight.

The (meth) acrylic resin (A) contains a structural unit derived from a (meth) acrylic monomer having a hydroxyl group. In order to improve the adhesion between the adhesive layer and the optical member and the durability of the adhesive layer, it is advantageous to include the constituent unit. The (meth) acrylic monomer having a hydroxyl group is preferably a (meth) acrylate having a hydroxyl group. Specific examples of the (meth) acrylate having a hydroxyl group include, for example, 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, A hydroxyl-containing alkyl ester of (meth) acrylic acid such as 2- (2-hydroxyethoxy) ethyl (meth) acrylate, 2- or 3-chloro-2-hydroxypropyl (meth) acrylate; and such as Polyfunctional alcohols such as diethylene glycol mono (meth) acrylate and partial esterifications of (meth) acrylic acid and the like. From the viewpoint of the adhesiveness between the adhesive layer and the optical member and the durability (especially heat resistance) of the adhesive layer, the monomer having a hydroxyl group is preferably a (meth) acrylate having a hydroxyl group, and ( Hydroxy-containing alkyl esters of (meth) acrylic acid are preferred. Of an alkyl moiety in a hydroxy-containing alkyl ester of (meth) acrylic acid The carbon number is preferably from 1 to 8, and more preferably from 1 to 6.

The content of the constituent units derived from the (meth) acrylic monomer having a hydroxyl group may be, for example, 3.5% by weight or less, and may be greater than 3.5% of the total constituent units constituting the (meth) acrylic resin (A). It is usually 10% by weight or less.

The (meth) acrylic resin (A) is a structural unit capable of containing a monomer having a polar functional group other than the (meth) acrylic monomer having a hydroxyl group. The monomer having a polar functional group is preferably a (meth) acrylic monomer having a polar functional group.

As a polar functional group which this monomer has, a carboxyl group (free carboxyl group), an amine group, a heterocyclic group (for example, an epoxy group), etc. are mentioned.

Specific examples of the monomer having other polar functional groups include monomers having a carboxyl group such as (meth) acrylic acid, (meth) acrylic acid β-carboxyethyl ester; such as acrylfluorenylmorpholine, and vinylcaprolactone. Amidine, N-vinyl-2-pyrrolidone, vinylpyridine, tetrahydrofurfuryl (meth) acrylate, tetrahydrofurfuryl acrylate modified with caprolactone, 3,4-epoxy (meth) acrylate Cyclohexyl methyl ester, glycidyl (meth) acrylate, 2,5-dihydrofuran and other monomers having heterocyclic groups; such as aminoethyl (meth) acrylate, N (meth) acrylate, Monomers such as N-dimethylaminoethyl ester, dimethylaminopropyl (meth) acrylate, and the like having an amino group different from a heterocyclic ring. The monomers having other polar functional groups may be used alone or in combination of two or more.

In addition to the (meth) acrylic monomer having a hydroxyl group, the use of a monomer having another polar functional group, especially a (meth) acrylic monomer having a carboxyl group, improves the adhesion between the adhesive layer and the optical member. And sticky The durability (especially heat resistance) of the adhesive layer is advantageous.

The content of the constituent units derived from a monomer having another polar functional group (preferably a (meth) acrylic monomer having a carboxyl group) is included in the total constituent units constituting the (meth) acrylic resin (A), It is preferably 5% by weight or less, and more preferably 4% by weight or less. When the content of the constituent unit derived from a monomer having another polar functional group is more than 5% by weight, the durability, especially the heat resistance of the adhesive layer tends to be insufficient. On the other hand, the content of the constituent unit derived from a monomer having another polar functional group is usually 0.1% by weight or more, preferably 0.2% by weight or more, and more preferably 0.3% by weight or more when the constituent unit is contained. When the content of the constituent unit derived from a monomer having another polar functional group is less than 0.1% by weight, the use effect is not easily observed. Of the total constituent units constituting the (meth) acrylic resin (A), the constituent units derived from all monomers having a polar functional group containing a (meth) acrylic monomer having a hydroxyl group are usually 0.1 to 15 % By weight, preferably 0.2 to 10% by weight.

The (meth) acrylic resin (A) may further contain a monomer derived from a monomer having one olefinic double bond and at least one aromatic ring in the molecule (however, the monomer represented by the formula (I) Or a monomer having the above-mentioned polar functional group). A suitable example is a (meth) acrylic monomer having an aromatic ring. Although such a (meth) acrylic monomer having an aromatic ring includes neopentyl glycol benzoate (meth) acrylate and the like, it is particularly a phenoxy-containing ethyl group represented by the following formula (II) (Meth) acrylates such as (meth) acrylates having an aryloxyalkyl group are preferred:

Monomers having a olefinic double bond and at least one aromatic ring in the molecule, such as a phenoxyethyl-containing (meth) acrylate, may be used alone or in combination of two or more.

In the above formula (II), R ³ represents a hydrogen atom or a methyl group, n represents an integer of 1 to 8, and R ⁴ represents a hydrogen atom, an alkyl group, an aralkyl group, or an aryl group. When R ⁴ is an alkyl group, its carbon number can be about 1 to 9; when it is an aralkyl group, its carbon number can be about 7 to 11; and when it is an aryl group, its carbon number can be about 6 to 10.

Examples of the alkyl group having 1 to 9 carbon atoms constituting R ⁴ in the formula (II) include methyl, butyl, nonyl, and the like. Examples of the aralkyl group having 7 to 11 carbon atoms include benzene. A methyl group, a phenethyl group, a naphthylmethyl group, etc. As an aryl group having 6 to 10 carbon atoms, a phenyl group, a tolyl group, a naphthyl group, and the like are mentioned.

Specific examples of the phenoxyethyl group-containing (meth) acrylate represented by formula (II) include 2-phenoxyethyl (meth) acrylate and 2- (2-benzene) (meth) acrylate (Ethoxyethoxy) ethyl ester, (meth) acrylate of ethylene oxide-modified nonylphenol, 2- (o-phenylphenoxy) ethyl (meth) acrylate, and the like. In particular, phenoxyethyl-containing (meth) acrylates include 2-phenoxyethyl (meth) acrylate, 2- (o-phenylphenoxy) ethyl (meth) acrylate, and Preferably, 2- (2-phenoxyethoxy) ethyl (meth) acrylate is used.

The content of the constituent units derived from the monomer having an aromatic ring is usually 0 in the total constituent units constituting the (meth) acrylic resin (A). To 20% by weight (e.g. 6 to 12% by weight). However, in order to make the glass transition temperature of the (meth) acrylic-type resin (A) into the predetermined range mentioned later, it may be preferable not to contain the structural unit derived from the monomer which has an aromatic ring.

The (meth) acrylic resin (A) may contain a monomer derived from a (meth) acrylic monomer other than the above-mentioned formula (I), a monomer having a polar functional group, and a monomer having an aromatic ring. A constituent unit of other monomers (hereinafter also referred to as "other monomers"). Examples of other monomers include a structure derived from a (meth) acrylic monomer having an alicyclic structure in the molecule (preferably (meth) acrylate having an alicyclic structure in the molecule). Unit, a structural unit derived from a styrene-based monomer, a structural unit derived from a vinyl-based monomer, a structural unit derived from a monomer having a plurality of (meth) acrylfluorenyl groups in a molecule, ) The constituent units of the acrylamide compound. Other monomers may be used alone or in combination of two or more.

The alicyclic structure in the (meth) acrylate having an alicyclic structure in the molecule refers to a cycloparaffin structure having a carbon number of usually 5 or more, preferably about 5 to 7. Specific examples of the (meth) acrylic acid ester having an alicyclic structure include isopropyl (meth) acrylate, cyclohexyl (meth) acrylate, dicyclopentyl (meth) acrylate, and (meth) ) Cyclododecyl acrylate, methyl cyclohexyl (meth) acrylate, trimethyl cyclohexyl (meth) acrylate, tertiary butyl cyclohexyl (meth) acrylate, cyclohexyl (meth) acrylate Phenyl ester, cyclohexyl α-ethoxyacrylate, and the like.

Specific examples of the styrene-based monomer include: styrene; for example, methylstyrene, dimethylstyrene, trimethylstyrene, ethylstyrene, diethylstyrene, triethylstyrene, Propylstyrene, butylbenzene Alkyl styrenes such as ethylene, hexyl styrene, heptyl styrene, octyl styrene; halogenated styrenes such as fluorostyrene, chlorostyrene, bromostyrene, dibromostyrene, iodostyrene; nitrobenzene Ethylene, ethenylstyrene, methoxystyrene, divinylbenzene, etc.

Specific examples of vinyl monomers include: vinyl acetate, vinyl propionate, vinyl butyrate, vinyl 2-ethylhexanoate, vinyl laurate, and other fatty acid vinyl esters; such as vinyl chloride and vinyl bromide Isohalogenated ethylene; such as vinylidene chloride and other halogenated vinylidene; such as vinylpyridine, vinylpyrrolidone, vinylcarbazole and other nitrogen-containing aromatic ethylene; such as butadiene, isoprene, chloroprene Iso-conjugated diene monomers; acrylonitrile, methacrylonitrile, etc.

Specific examples of the monomer having a plurality of (meth) acrylfluorene groups in the molecule include, for example, 1,4-butanediol di (meth) acrylate, and 1,6-hexanediol di (methyl) ) Acrylate, 1,9-nonanediol di (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, tetraethylene glycol di (methyl) ) Acrylic ester, tripropylene glycol di (meth) acrylate, etc. monomers having 2 (meth) acrylfluorene groups in the molecule; such as trimethylolpropane tri (meth) acrylate, etc. have 3 in the molecule (Meth) acrylfluorenyl monomers and the like.

Specific examples of the (meth) acrylamide compound include N-hydroxymethyl (meth) acrylamide, N- (2-hydroxyethyl) (meth) acrylamide, N- (3- Hydroxypropyl) (meth) acrylamide, N- (4-hydroxybutyl) (meth) acrylamide, N- (5-hydroxypentyl) (meth) acrylamide, N- (6 -Hydroxyhexyl) (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, N-isopropyl (methyl) Acrylamide, N- (3-di Methylaminopropyl) (meth) acrylamide, N- (1,1-dimethyl-3-butoxybutyl) (meth) acrylamide, N- [2- (2- Pendantoxy-1-imidazolidinyl) ethyl] (meth) acrylamide, 2-propenylamino-2-methyl-1-propanesulfonic acid, N- (methoxymethyl) propene Ammonium amine, N- (ethoxymethyl) (meth) acrylamide, N- (propoxymethyl) (meth) acrylamide, N- (1-methylethoxymethyl) (Meth) acrylamide, N- (1-methylpropoxymethyl) (meth) acrylamide, N- (2-methylpropoxymethyl) (meth) acrylamide [ Alias: N- (isobutoxymethyl) (meth) acrylamide], N- (butoxymethyl) (meth) acrylamide, N- (1,1-dimethylethoxy) Methyl) (meth) acrylamide, N- (2-methoxyethyl) (meth) acrylamide, N- (2-ethoxyethyl) (meth) acrylamide, N- (2-propoxyethyl) (meth) acrylamide, N- [2- (1-methylethoxy) ethyl] (meth) acrylamide, N- [2- ( 1-methylpropoxy) ethyl] (meth) acrylamide, N- [2- (2-methylpropoxy) ethyl] (meth) acrylamide [alias: N- (2 -Isobutoxyethyl) (meth) acrylamide], N- (2-butoxyethyl) (methyl ) Acrylamide, N- [2- (1,1- dimethylethoxy) ethyl] (meth) acrylamide and the like. In particular, N- (methoxymethyl) acrylamide, N- (ethoxymethyl) acrylamide, N- (propoxymethyl) acrylamide, N- (butoxymethyl) Group) acrylamide, N- (2-methylpropoxymethyl) acrylamide.

Of the total constituent units constituting the (meth) acrylic resin (A), the (meth) acrylic resin (A) is usually contained at a ratio of 0 to 20% by weight, preferably 0 to 10% by weight. The constituent units of other monomers.

The adhesive composition may contain two or more kinds of (meth) acrylic resins (meth) acrylic resins (A). The adhesive composition may contain other (meth) groups other than the (meth) acrylic resin (A). Acrylic resin. Examples of other (meth) acrylic resins are (meth) acrylic resins having a structural unit derived from a (meth) acrylic monomer represented by formula (I) and having no polar functional group. However, the adhesive composition preferably contains (meth) acrylic resin (A) as a main component, and the content of (meth) acrylic resin (A) is in the total of all (meth) acrylic resins. It is preferably 60% by weight or more, preferably 80% by weight or more, and more preferably 90% by weight or more.

The (meth) acrylic resin (A) has a glass transition temperature (Tg) measured using a differential scanning calorimeter (DSC) of -10 ° C or lower, preferably -15 ° C or lower, and more preferably -20 ° C or lower. . By the adhesive composition of the present invention containing a (meth) acrylic resin (A) having a Tg of -20 ° C or lower, the adhesiveness between the adhesive layer and the optical member and the durability of the adhesive layer can be improved. From the viewpoint of durability, the Tg of the (meth) acrylic resin (A) is usually -55 ° C or higher, and preferably -50 ° C or higher.

The weight average molecular weight (Mw) of the (meth) acrylic resin (A) as calculated by gel permeation chromatography (GPC) in terms of standard polystyrene is preferably in the range of 500,000 to 2 million. A range of 600,000 to 1.8 million is preferable. When the Mw is 500,000 or more, the adhesiveness between the adhesive layer and the optical member is increased in a high-temperature and high-humidity environment, and the possibility of floating or peeling between the adhesive layer and the optical member tends to decrease, and The reworkability of the adhesive layer tends to be improved. When Mw is 2 million or less, when the adhesive layer is bonded to the optical member, even if the size of the optical member is changed, the adhesive layer is easy to change in accordance with the size change. Therefore, the adhesive layer and the optical member are changed. The adhesion and durability of the adhesive layer are Advantageously, with the above-mentioned followability, when an optical member with an adhesive layer is applied to a liquid crystal display device, the difference between the brightness of the peripheral portion of the liquid crystal cell and the brightness of the center portion disappears and can be suppressed. The tendency to discolor and uneven color. The molecular weight distribution represented by the ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is usually about 2 to 10, preferably 3 to 7.

The (meth) acrylic resin (A) and other (meth) acrylic resins that can be used arbitrarily can be combined using well-known methods such as a solution polymerization method, a block polymerization method, a suspension polymerization method, and an emulsion polymerization method. Manufacturing. In the production of a (meth) acrylic resin, a polymerization initiator can usually be used. The polymerization initiator is used in an amount of about 0.001 to 5 parts by weight based on 100 parts by weight of the total of all the monomers used in the production of the (meth) acrylic resin. Moreover, (meth) acrylic-type resin can also be manufactured using the method which superpose | polymerizes by active energy rays, such as an ultraviolet-ray.

As a polymerization initiator, a thermal polymerization initiator, a photopolymerization initiator, etc. can be used. Examples of the photopolymerization initiator include 4- (2-hydroxyethoxy) phenyl (2-hydroxy-2-propyl) ketone and the like. Examples of the thermal polymerization initiator include, for example, 2,2'-azobisisobutyronitrile, 2,2'-azobis (2-methylbutyronitrile), and 1,1'-azo Bis (cyclohexane-1-carbonitrile), 2,2'-azobis (2,4-dimethylvaleronitrile), 2,2'-azobis (2,4-dimethyl-4 -Methoxyvaleronitrile), azo-2,2'-azobis (2-methylpropionate), 2,2'-azobis (2-hydroxymethylpropionitrile), etc. Compounds; such as lauryl peroxide, third butyl hydroperoxide, benzamidine peroxide, third butyl peroxybenzoate, cumene hydroperoxide, diisopropyl peroxydicarbonate, peroxidation two Organic peroxides such as dipropyl carbonate, tertiary butyl peroxydecanoate, tertiary butyl peroxytrimethylacetate, and peroxy (3,5,5-trimethylhexamidine); such as persulfuric acid Inorganic peroxides such as potassium, ammonium persulfate, and hydrogen peroxide. In addition, a redox-based initiator in which a peroxide and a reducing agent are used in combination can also be used as a polymerization initiator.

As a method for producing a (meth) acrylic resin, among the methods disclosed above, a solution polymerization method is preferred. An example of the solution polymerization method is to mix the monomers used and the organic solvent, add a thermal polymerization initiator under a nitrogen atmosphere, and stir at about 40 to 90 ° C, preferably about 50 to 80 ° C, for 3 to 15 About hours. In order to control the reaction, a monomer or a thermal polymerization initiator may be added continuously or intermittently during the polymerization, or it may be added in a state of being dissolved in an organic solvent. As the organic solvent, for example, aromatic hydrocarbons such as toluene and xylene; esters such as ethyl acetate and butyl acetate; aliphatic alcohols such as propanol and isopropanol; such as acetone and methyl Ketones such as ethyl ketone and methyl isobutyl ketone.

[2] Crosslinking agent (B)

The adhesive composition is prepared by further mixing a crosslinking agent in the (meth) acrylic resin as described above. The cross-linking agent is a compound having at least two functional groups in the molecule, and the functional group is capable of interacting with a constituent unit of the (meth) acrylic resin, and particularly derived from a (meth) acrylic monomer containing a polar functional group. The crosslinking is specifically exemplified by isocyanate compounds, epoxy compounds, metal clamp compounds, aziridine compounds and the like.

Isocyanate-based compounds (hereinafter also referred to as isocyanate-based compounds Crosslinking agent (B-1)) is a compound having at least two isocyanate groups (-NCO) in the molecule. Examples include toluene diisocyanate, hexamethylene diisocyanate, and isophorone diisocyanate. , Xylylene diisocyanate, hydrogenated xylylene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, naphthalene diisocyanate, triphenylmethane triisocyanate, and the like. In addition, an adduct obtained by reacting a polyhydric alcohol such as glycerin and trimethylolpropane with these isocyanate compounds, and an isocyanate compound made into a dimer, trimer, or the like can also be used as an adhesive composition物 的 crosslinking agent. A mixture of two or more isocyanate-based compounds can also be used.

The epoxy-based compound is a compound having at least two epoxy groups in the molecule. Examples of the epoxy-based compound include bisphenol A epoxy resin, ethylene glycol diglycidyl ether, and polyethylene glycol diepoxy. Propyl ether, glycerol diglycidyl ether, glycerol triglycidyl ether, 1,6-hexanediol diglycidyl ether, trimethylolpropane triglycidyl ether, N, N- Diglycidylaniline, N, N, N ', N'-tetraglycidyl-m-xylylenediamine, 1,3-bis (N, N-glycidylaminomethyl) ring Hexane, etc. It is also possible to use a mixture of two or more epoxy-based compounds.

Examples of metal clamp compounds include acetoacetone or acetoacetate which are coordinated to aluminum, iron, copper, zinc, tin, titanium, nickel, antimony, magnesium, vanadium, chromium, or zirconium. Valence metal compounds.

Acrylpropane-based compounds, also known as ethyleneimines, have at least two 3-membered ring skeletons composed of one nitrogen atom and two carbon atoms in the molecule. Examples include diphenylmethane -4,4'-double (1-Acyclopropanecarboxamide), Toluene-2,4-bis (1-Acyclopropanecarboxamide), Triethylene melamine, m-xylylenemethylbis-1- (2-methylazepine) Cyclopropane), ginsane-1-acylcyclopropanephosphine oxide, hexamethylene-1,6-bis (1-acylcyclopropaneformamide), trimethylolpropane-tri-β-acylcyclopropane Propionate, tetramethylolmethane-tri-β-acylcyclopropanepropionate and the like.

Among these cross-linking agents, isocyanate-based cross-linking agents (B-1), particularly xylylene diisocyanate, toluene diisocyanate, or hexamethylene diisocyanate, can be suitably used, or the isocyanate compounds can An adduct obtained by reacting a polyhydric alcohol such as glycerin and trimethylolpropane, and an isocyanate compound made of a dimer, trimer, or the like, or a mixture of such isocyanate compounds. When the (meth) acrylic resin (A) has a polar functional group selected from a free carboxyl group, a hydroxyl group, an amine group, and an epoxy ring, an isocyanate-based crosslinking agent (B-1) is used as the crosslinking agent (B ) Is at least one kind. Examples of suitable isocyanate-based crosslinking agents (B-1) include xylylene diisocyanate, an adduct obtained by reacting xylylene diisocyanate with a polyhydric alcohol, and xylylene diisocyanate. Dimer, terpolymer of xylylene diisocyanate, toluene diisocyanate, adduct obtained by reacting toluene diisocyanate with polyol, dimer of toluene diisocyanate, and terpolymer of toluene diisocyanate Or hexamethylene diisocyanate, an adduct obtained by reacting hexamethylene diisocyanate with a polyol, a dimer of hexamethylene diisocyanate, and a terpolymer of hexamethylene diisocyanate.

The crosslinking agent (B) is usually formulated at a ratio of 0.01 to 5 parts by weight based on 100 parts by weight of the (meth) acrylic resin (A). Crosslinking agent (B) The blending amount is preferably about 0.1 to 5 parts by weight, and more preferably about 0.2 to 3 parts by weight based on 100 parts by weight of the (meth) acrylic resin (A). When the amount of the crosslinking agent (B) is 0.01 parts by weight or more, particularly 0.1 parts by weight or more, based on 100 parts by weight of the (meth) acrylic resin (A), the durability of the adhesive layer tends to be improved. It is preferable, and when it is 5 parts by weight or less, it is preferable because the discoloration becomes inconspicuous when an optical member with an adhesive is applied to a liquid crystal display device.

[3] Compound (C)

The adhesive composition usually contains a crosslinking catalyst (C-1) and an alkoxy group-containing compound (C-2). The adhesive composition of the present invention containing a cross-linking catalyst (C-1) and an alkoxy group-containing compound (C-2) can be easily stored at a high temperature of 50 ° C for 48 hours. The ratio (P ₅₀ / P ₂₃ ) of the peeling force (P ₅₀ ) to the alkali-free glass plate to the peeling force (P ₂₃ ) to the alkali-free glass plate after storage at 23 ° C. for 24 hours becomes 4.5 or more.

As the crosslinking catalyst (C-1), an organic acid salt is usually used, and a salt composed of an organic acid and a base having a carboxylic acid terminal, that is, an organic carboxylic acid salt is preferred. When an organic carboxylate is used as the cross-linking catalyst (C-1), the counter-cation of the carboxylate anion is preferably a trivalent or lower cation. The organic acid salt may be used singly or in combination of two or more kinds.

Examples of the counter cation include a metal ion, an ammonium ion, and a cation having a heterocyclic structure. Preferred examples of the metal ion include alkali metal ions and alkaline earth metal ions. Preferred examples of the cation having a heterocyclic structure include a pyrrolinium ion, an imidazolium ion, a triazolium ion, a pyrrolidinium ion, a pyridinium ion, and piperidine. Onium ion.

As the carboxylate anion of the organic acid salt, for example, straight-chain saturated alkylcarboxylate ions such as formate ion, acetate ion, propionate ion, heptanoate ion, octanoate ion, and laurate ion; (Meth) acrylic acid, oleic acid and other linear unsaturated alkyl carboxylate ions; such as benzoic acid, cinnamic acid and other aromatic carboxylic acid ions; such as nicotinic acid and other heterocyclic structure carboxylic acid ions; such as succinic acid , Fumarate, phthalic acid and other dicarboxylate ions; such as 2- (2-ethoxy) ethoxycarboxylate ions and other anions of carboxylates with an oxyethyl skeleton.

The content of the crosslinking catalyst (C-1) is usually 0.0001 to 5 parts by weight, preferably 0.0005 to 3 parts by weight, and more preferably 0.0007 to 1 with respect to 100 parts by weight of the (meth) acrylic resin (A). It is more preferably 0.001 to 1 part by weight, and particularly preferably 0.0015 to 0.5 part by weight. As long as the content is within this range, the adhesion between the adhesive layer and the optical member can be obtained, and the durability when the adhesive layer is bonded to the optical member is good, and the curing time of the adhesive layer can be shortened. Adhesive composition.

The alkoxy group-containing compound (C-2) is a compound containing at least one alkoxy group in the molecule. The alkyleneoxy group is preferably contained in the compound (C-2) as an alkylenedioxy group (-O-alkylene-O-). Examples of the alkoxy group include ethoxy group, propyleneoxy group, and butyloxy group, but are not limited thereto. Examples of the alkoxy group-containing compound include polyalkylene glycols, and specifically, there are polyethylene glycol, polypropylene glycol, polybutylene glycol, and copolymers of two or more such polyalkylene glycols.

The average number of repeats of the alkoxy groups constituting the polyalkylene glycol is not particularly limited. The limit is usually 1 to 50, preferably 2 to 40, and more preferably 3 to 30. Here, the "average repeat number of alkoxy groups" refers to the average number of repeats of alkoxy groups in the portion of the "polyalkoxy chain" contained in the molecular structure of the polyalkylene glycol. . In addition, at least one of the hydroxyl groups of the polyalkanediol may be substituted with an alkoxy group such as a methoxy group, an ethoxy group, or a propoxy group. Examples include polyalkylene glycol monomethyl ether, polyalkylene glycol monoethyl ether, polyalkylene glycol dimethyl ether, polyalkylene glycol diethyl ether, and the like.

The compound (C-2) containing an alkoxy group may contain at least one double bond in the molecule in addition to the alkoxy group. A preferable example of the double bond is a double bond contained in a (meth) acrylfluorenyl group. The alkoxy group-containing compound (C-2) may be used alone or in combination of two or more. With the adhesive layer composed of the adhesive composition containing the alkoxy group-containing compound (C-2), it is also possible to suppress the peeling force to the adhesive layer from the release film laminated on the surface of the adhesive layer. Strengthened by heat.

From the viewpoints of the adhesiveness between the adhesive layer and the optical member, and the durability when the adhesive layer is bonded to the optical member, a preferable example of the above-mentioned alkylene dioxy group is a carbon number of 1 to 4 The alkanedioxy group is more preferably a straight-chain or branched alkanedioxy group having 1 to 3 carbon atoms, and still more preferably an ethanedioxy group (-OC ₂ H ₄ -O-). In addition, the same applies to the example of an alkoxy group other than the alkoxy group. The alkoxy group is preferably an alkoxy group having 1 to 4 carbon atoms, and more preferably a linear or alkoxy group having 1 to 3 carbon atoms. Branched alkoxy is more preferably ethoxy (-OC ₂ H _4- ).

The compound (C-2) is represented by the following formula (C-2a) from the viewpoints of the adhesiveness between the adhesive layer and the optical member, and the durability when the adhesive layer is bonded to the optical member. The (meth) acrylfluorenyl-containing compound (C-2a) is preferred:

The compound (C-2a) is more preferable. In the formula, h is an integer of 1 to 6, Q ¹ is a hydrogen atom or a methyl group, and Q ⁰ is a group having an h valence of at least one butanedioxy group. The compound (C-2) may contain two or more compounds (C-2a). h is preferably an integer of 1 to 3.

The group represented by Q ⁰ having an h-valence of at least one butanedioxy group can be an h-valent hydrocarbon group having at least one butanedioxy group and having at least one ethylene-dioxy group Preferable to trivalent hydrocarbon group. Examples of the hydrocarbon group include the groups represented by Q ⁰¹ , Q ⁰² , Q ^03, and Q ⁰⁴ described below.

In Q ⁰¹ , Q ² represents an alkyl, aryl, or aralkyl group having 1 to 4 carbon atoms, which may be substituted by an alkoxy group having 1 to 3 carbon atoms, and L represents a single bond or 1 to 4 carbon atoms. Is an integer of 1 to 50 (for example, 1 to 30). The number of carbon atoms of the aryl group capable of forming Q ² is preferably 6 to 20, and the number of carbon atoms of the aralkyl group is preferably 7 to 20. In Q ⁰² , j is an integer representing 1 to 40 (for example, 1 to 30). In Q ⁰³ , y and z are each independently an integer of 1 to 40 (for example, 1 to 30), and y + z can be an integer of 1 to 40 (for example, 1 to 30). In Q ⁰⁴ , e, f, and g each independently represent an integer of 1 to 20 (for example, 1 to 10), and e + f + g can be an integer of 1 to 30 (for example, 1 to 25).

As a compound (C-2a) which can be suitably used, the compound (C-2a-1) represented by the following formula (C-2a-1) can be mentioned:

The compound (C-2) may contain two or more compounds (C-2a-1). The compound (C-2a-1) is a compound in which Q ⁰ is Q ^{01 in} the above formula (C-2a). Formula ^{Q 1, L, i, Q} 2 represents a system with the same meaning. In the compound (C-2a-1), L is preferably a single bond, and i is preferably an integer of 7 to 35, and more preferably an integer of 9 to 25. Q ^{2 is} preferably an alkyl group having 1 to 3 carbon atoms or an aryl group having 6 to 20 carbon atoms. Specific examples of Q ² include methyl, ethyl, n-propyl, isopropyl, phenyl, Biphenyl.

As specific examples of the compound (C-2a-1), Q ¹ , L, i, and Q ² are shown in Table 1 below.

Other examples of the compound (C-2a) that can be suitably used are compounds in which Q ⁰ is Q ^{04 in} the formula (C-2a). At this time, h in the formula (C-2a) is 3. The compound (C-2) may contain two or more compounds in which Q ⁰ is Q ⁰⁴ . In Q ⁰⁴ , e + f + g is preferably an integer of 5 to 25.

Other examples of suitable compounds capable of (C-2a) used, the compound of the above formula (C-2a) in the Q ⁰ to Q ⁰³ of the system. At this time, h in the above formula (C-2a) is 2. The compound (C-2) may contain two or more compounds in which Q ⁰ is Q ⁰³ . In Q ⁰³ , y + z is preferably an integer of 5 to 25.

The content of the compound (C-2) is usually 0.1 to 5 parts by weight, preferably 0.15 to 5 parts by weight, and more preferably 0.2 to 4.5 parts by weight, with respect to 100 parts by weight of the (meth) acrylic resin (A). More preferably, it is 0.5 to 4 parts by weight. As long as the content is within this range, the adhesiveness between the adhesive layer and the optical member can be obtained, and the durability when the adhesive layer is bonded to the optical member is good, and the curing time of the adhesive layer can be shortened. The adhesive composition can also suppress the increase in peeling force.

[4] Ionic compound (D)

The adhesive composition may further contain an ionic compound (D) as an antistatic agent for imparting antistatic properties to the adhesive layer. The ionic compound (D) is a compound having an inorganic cation or an organic cation, and an inorganic anion or an organic anion. Two or more ionic compounds (D) may be used.

Examples of the inorganic cation include alkali metal ions such as lithium cation [Li ⁺ ], sodium cation [Na ⁺ ], and potassium cation [K ⁺ ]; such as beryllium cation [Be ²⁺ ] and magnesium cation [Mg ^{2 +} ], Calcium cations [Ca ²⁺ ] and other alkaline earth metal ions.

Examples of the organic cation include an imidazolium cation, a pyridinium cation, a pyrrolidium cation, an ammonium cation, a sulfonium cation, and a sulfonium cation.

Among the above-mentioned cationic components, an organic cationic component can be suitably used because it has excellent compatibility with the adhesive composition. Among the organic cation components, in particular, from the viewpoint that it is not easy to be charged when the release film provided on the adhesive layer is peeled off, in particular, a pyridinium cation and an imidazolium cation can be suitably used.

As the inorganic anions are, for example, include: chlorine anions [Cl ^-], bromine anion [Br ^-], iodide anion [I ^-], tetrachloroaluminate anion [AlCl ₄ ^-], heptachlor anions aluminum [Al ₂ Cl ₇ ^-], tetrafluoroborate anion [BF ₄ ^-], hexafluorophosphate anions [PF ₆ ^-], perchloric acid anion [ClO ₄ ^-], nitrate anions [NO ₃ ^-], hexafluoro arsenic anion [AsF ₆ ^-], hexafluoroantimonate anion [SbF ₆ ^-], niobium hexafluorophosphate anion [NbF ₆ ^-], six tantalum fluoride anion [TaF ₆ ^-], dicyanamide anion [(CN) ₂ N ^-] and the like.

As the organic anions are, for example, include: acetate anion [CH ₃ COO ^-], trifluoroacetate anion [CF ₃ COO ^-], methanesulfonic acid anion [CH ₃ SO ₃ ^-], triflate anion [CF ₃ SO ₃ ^-], p-toluenesulfonate anion _{[p-CH 3 C 6 H} 4 SO 3 -], bis (sulfo-fluoro-acyl) imide anion ^{_{[(FSO 2) 2 N -}} ], bis (C fluoro methanesulfonamide acyl) imide anion _{[(CF 3 SO 2) 3} N -], reference (trifluoromethanesulfonyl acyl) methanation anions _{[(CF 3 SO 2) 3} C -], dimethylphosphinic anion ^{_{[(CH 3) 2 POO -}} ], ( poly) hydrogen fluoride anion ^{_{[F (HF) n -]}} (n is about 1 to 3), thiocyanate anion [SCN ^-], perfluoro butyl sulfonate anion ^{_{[C 4 F 9 SO 3 -}} ], bis (pentafluoroethane sulfonyl acyl) imide anion _{[(C 2 F 5 SO 2} ) 2 N -], perfluoro acid anions [C ₃ F ₇ COO ^- ], (trifluoromethanesulfonyl acyl) (carbonyl trifluoromethanesulfonyl) imide anion _{[(CF 3 SO 2) (} CF 3 CO) N -], -1,3- perfluoropropane disulfonate anion ^[- O _{3 S (CF 2) 3 SO} 3 -], carbonate anion [CO ₃ ^2-] and the like.

Among the above-mentioned anionic components, an ionic compound (D) having excellent antistatic properties can be supplied, and in particular, an anionic component containing a fluorine atom can be suitably used. Specific examples of the anion component containing a fluorine atom include a bis (fluorosulfonyl) imide anion, a hexafluorophosphate anion, or a bis (trifluoromethanesulfonyl) imide anion.

Specific examples of the ionic compound (D) can be appropriately selected from a combination of the above-mentioned cationic component and anionic component. Examples of the ionic compound (D) having an organic cation are classified according to the structure of each organic cation, and the following are mentioned.

Pyridinium salts: N-hexylpyridinium hexafluorophosphate, N-octylpyridinium hexafluorophosphate, N-octyl-4-methylpyridinium hexafluorophosphate, N-butyl-4-methyl Pyridinium hexafluorophosphate, N-decylpyridinium bis (fluorosulfonyl) imine, N-dodecylpyridinium bis (fluorosulfonyl) imine, N-tetradecylpyridinium bis (fluoro Sulfofluorenyl) imine, N-hexadecylpyridinium bis (fluorosulfonyl) imine, N-dodecyl-4-methylpyridinium bis (fluorosulfonyl) imine, N-tetradecyl-4-methylpyridinium bis (fluorosulfonyl) imine, N-hexadecyl-4-methylpyridinium bis (fluorosulfonyl) imine, N-benzyl- 2-methylpyridinium bis (fluorosulfonyl) imine, N-benzyl-4-methylpyridinium bis (fluorosulfonyl) imine, N-hexylpyridinium bis (trifluoromethanesulfonyl) Group) imine, N-octylpyridinium bis (trifluoromethanesulfonyl) imine, N-octyl-4-methylpyridinium bis (trifluoromethanesulfonyl) imine, N-butyl 4-methylpyridinium bis (trifluoromethanesulfonyl) imine.

Imidazolium salts: 1-ethyl-3-methylimidazolium hexafluorophosphate, 1-ethyl-3-methylimidazolium p-toluenesulfonate, 1-ethyl-3-methylimidazolium bis ( Fluorosulfonyl) imine, 1-ethyl-3-methylimidazolium bis (trifluoromethanesulfonyl) imine, 1-butyl-3-methylimidazolium methanesulfonate, 1-butane 3-methylimidazolium bis (fluorosulfonyl) imine.

Pyrrolidinium salts: N-butyl-N-methylpyrrolidinium hexafluorophosphate, N-butyl-N-methylpyrrolidinium bis (fluorosulfonyl) imine, N-butyl-N -Methylpyrrolidinium bis (trifluoromethanesulfonyl) imine.

Grade 4 ammonium salt: tetrabutylammonium, hexafluorophosphate, Tetrabutylammonium p-toluenesulfonate, (2-hydroxyethyl) trimethylammonium bis (trifluoromethanesulfonyl) imine, (2-hydroxyethyl) trimethylammonium dimethylphosphinate.

Moreover, when the example of the ionic compound (D) which has an inorganic cation is mentioned, it is as follows.

Lithium bromide, lithium iodide, lithium tetrafluoroborate, lithium hexafluorophosphate, lithium thiocyanate, lithium perchlorate, lithium trifluoromethanesulfonate, lithium bis (fluorosulfonyl) imide, bis (trifluoromethanesulfonyl) Lithium imine, lithium bis (pentafluoroethanesulfonyl) imide, lithium ginseng (trifluoromethanesulfonyl) lithium methanide, lithium p-toluenesulfonate, sodium hexafluorophosphate, bis (fluorosulfonyl) imine Sodium, sodium bis (trifluoromethanesulfonyl) imide, sodium p-toluenesulfonate, potassium hexafluorophosphate, potassium bis (fluorosulfonyl) imide, Potassium bis (trifluoromethanesulfonyl) imide, potassium p-toluenesulfonate.

The ionic compound (D) is preferably solid at room temperature. Compared with the case of using the ionic compound (D) which is liquid at normal temperature, it is possible to maintain the antistatic performance for a long period of time. From the viewpoint of such long-term stability of antistatic properties, the ionic compound (D) preferably has a melting point of 30 ° C or higher, and furthermore, 35 ° C or higher. On the other hand, when the melting point is too high, the compatibility with the (meth) acrylic resin (A) becomes poor. Therefore, the melting point is preferably 90 ° C or lower, more preferably 70 ° C or lower, and more preferably less than 50 ° C. ℃.

The content of the ionic compound (D) in the adhesive composition is preferably 0.2 to 8 parts by weight, more preferably 0.2 to 5 parts by weight, and more preferably 100 parts by weight of the (meth) acrylic resin (A). It is preferably 0.3 to 5 parts by weight, and particularly preferably 0.5 to 3 parts by weight. A content of the ionic compound (D) of 0.2 part by weight or more is advantageous for improving the antistatic performance, and 8 parts by weight or less is advantageous for maintaining the durability of the adhesive layer.

[5] Silane compound (E)

The adhesive composition can further contain a silane compound (E). Thereby, the adhesiveness of an adhesive layer and optical members, such as a glass substrate, can be improved.

Examples of the silane compound (E) include vinyltrimethoxysilane, vinyltriethoxysilane, vinyl ginseng (2-methoxyethoxy) silane, and N- (2-amine group). (Ethyl) -3-aminopropylmethyldimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxy Silane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyl Trimethoxysilane, 3-chloropropylmethyldimethoxysilane, 3-chloropropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-hydrothiopropyl Trimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropyldimethoxymethyl Silane, 3-cyclopropoxypropylethoxydimethylsilane, etc. Two or more silane compounds can also be used.

The silane compound (E) may be a silicone oligomer type. When a silicone oligomer is displayed as a (monomer) oligomer, the following are mentioned, for example.

3-hydrothiopropyltrimethoxysilane-tetramethoxysilane copolymer, 3-hydrothiopropyltrimethoxysilane-tetraethoxysilane copolymer, 3-hydrothiopropyltriethoxy Hydroxythiopropyl-containing copolymers such as silane-tetramethoxysilane copolymers, 3-hydrothiopropyltriethoxysilane-tetraethoxysilane copolymers; hydrogenthiomethyltrimethoxy groups Silane-tetramethoxysilane copolymer, hydrogenthiomethyltrimethoxysilane-tetraethoxysilane copolymer, hydrogenthiomethyltriethoxysilane-tetramethoxysilane copolymer, hydrogenthio group Hydrogenthiomethyl-containing copolymers such as methyltriethoxysilane-tetraethoxysilane copolymer; 3-glycidoxypropyltrimethoxysilane-tetramethoxysilane copolymer, 3- Glycidoxypropyltrimethoxysilane-tetraethoxysilane copolymer, 3-glycidoxypropyltriethoxysilane-tetramethoxysilane copolymer, 3-glycidoxypropyltriethoxysilane-tetraethoxysilane copolymer, 3-epoxy Propoxypropylmethyldimethoxysilane-tetramethoxysilane copolymer, 3-glycidoxypropylmethyldimethoxysilane-tetraethoxysilane copolymer, 3-epoxy Propoxypropylmethyldiethoxysilane-tetramethoxysilane copolymer, 3-glycidoxypropylmethyldiethoxysilane-tetraethoxysilane copolymer, etc. Copolymers of oxypropoxypropyl; 3-methacryloxypropyltrimethoxysilane-tetramethoxysilane copolymer, 3-methacryloxypropyltrimethoxysilane-tetraethyl Ethoxysilane copolymer, 3-methacryloxypropyltriethoxysilane-tetramethoxysilane copolymer, 3-methacryloxypropyltriethoxysilane-tetraethoxy Silane copolymer, 3-methacryloxypropylmethyldimethoxysilane-tetramethoxysilane copolymer, 3-methacryloxypropylmethyldimethoxysilane-tetraethyl Oxysilane copolymer, Copolymer of 3-methacryloxypropylmethyldiethoxysilane-tetramethoxysilane, 3-methacryloxypropylmethyldiethoxysilane-tetraethoxysilane copolymer Copolymers such as methacryloxypropyl; 3-acryloxypropyltrimethoxysilane-tetramethoxysilane copolymer, 3-acryloxypropyltrimethoxysilane-tetramethylene Ethoxysilane copolymer, 3-propenyloxypropyltriethoxysilane-tetramethoxysilane copolymer, 3-propenyloxypropyltriethoxysilane-tetraethoxysilane copolymer , 3-propenyloxypropylmethyldimethoxysilane-tetramethoxysilane copolymer, 3-propenyloxypropylmethyldimethoxysilane-tetraethoxysilane copolymer, 3 -Acrylic fluorene containing propylene ethoxypropylmethyldiethoxysilane-tetramethoxysilane copolymer, 3-propylene oxypropylmethyldiethoxysilane-tetraethoxysilane copolymer, etc. Copolymers of oxypropyl groups; vinyltrimethoxysilane-tetramethoxysilane copolymer, vinyltrimethoxysilane-tetraethoxysilane copolymer, vinyltriethoxysilane-tetraethylene Silane copolymer group, vinyl triethoxysilane Silane - tetraethyl orthosilicate copolymer, Vinylmethyldimethoxysilane-tetramethoxysilane copolymer, vinylmethyldimethoxysilane-tetraethoxysilane copolymer, vinylmethyldiethoxysilane-tetramethoxyoxy Silane copolymers, vinyl methyldiethoxysilane-tetraethoxysilane copolymers and other vinyl-containing copolymers; 3-aminopropyltrimethoxysilane-tetramethoxysilane copolymers, 3- Aminopropyltrimethoxysilane-tetraethoxysilane copolymer, 3-aminopropyltriethoxysilane-tetramethoxysilane copolymer, 3-aminopropyltriethoxysilane-tetramethoxysilane Ethoxysilane copolymer, 3-aminopropylmethyldimethoxysilane-tetramethoxysilane copolymer, 3-aminopropylmethyldimethoxysilane-tetraethoxysilane copolymer Copolymers containing amine groups such as 3-aminopropylmethyldiethoxysilane-tetramethoxysilane copolymer, 3-aminopropylmethyldiethoxysilane-tetraethoxysilane copolymer Things.

Most of the silane compounds (E) exemplified above are liquids. The content of the silane compound (E) in the adhesive composition is usually 0.01 to 10 parts by weight, preferably 0.05 to 5 parts by weight, and more preferably 0.2 to 100 parts by weight of the (meth) acrylic resin (A). To 0.4 parts by weight. When the content of the silane compound (E) is 0.01 parts by weight or more, the effect of improving the adhesion between the adhesive layer and the optical member such as a glass substrate is easily obtained. When the content is 10 parts by weight or less, bleeding of the silane compound (E) from the adhesive layer can be suppressed.

[6] other ingredients

Adhesive composition, which can contain cross-linking catalysts, weathering stabilizers, tackifiers, plasticizers, softeners, dyes, pigments, inorganic fillers, Additives such as light-scattering fine particles and resins other than (meth) acrylic resin (A). In addition, it is also useful to mix an ultraviolet curable compound in the adhesive composition to form an adhesive layer, and then irradiate the ultraviolet ray to harden it to become a hard adhesive layer. Examples of the crosslinking catalyst include hexamethylenediamine, ethylenediamine, polyethyleneimine, hexamethylenetetramine, ethylenediamine, triethylenetetramine, and isophor Amine compounds such as ketone diamine, trimethylene diamine, polyamine resin and melamine resin.

<Adhesive layer>

The adhesive layer of the present invention is one containing the above-mentioned adhesive composition of the present invention, and is typically composed of the adhesive composition of the present invention. The adhesive layer can be obtained by dissolving or dispersing each component constituting the above-mentioned adhesive composition in a solvent to form a solvent-containing adhesive composition, and then coating and drying the substrate film. The adhesive layer system of the present invention has excellent adhesion and durability, and can shorten the necessary curing time.

The base film is usually a plastic film, and a typical example thereof is a release film (separator) which has been subjected to a mold release treatment. The release film can be applied to, for example, a surface intended to form an adhesive layer on a film made of various resins such as polyethylene terephthalate, polybutylene terephthalate, polycarbonate, and polyarylate. Released from silicone treatment. For example, it is possible to form an adhesive layer by directly applying an adhesive composition on the release-treated surface of a release film, and to laminate the adhesive layer with a release film on an optical member to obtain an optical member with an adhesive layer. . Alternatively, the adhesive composition may be directly coated on the surface of the optical member to form an adhesive layer, and if necessary, a release film may be laminated on the outer surface of the adhesive layer to form an adhesive layer. Optical component of the adhesive layer. When the adhesive layer is provided on the surface of the optical member, it is better to perform a surface activation treatment such as a plasma treatment or a corona treatment on the bonding surface of the optical member and / or the bonding surface of the adhesive layer. Corona treatment is preferred.

The thickness of the adhesive layer is preferably 5 to 45 μm, more preferably 10 to 30 μm, and even more preferably 15 to 25 μm. When the thickness of the adhesive layer is within this range, it is advantageous for the adhesion between the adhesive layer and the optical member and the durability when the adhesive layer is bonded to the optical member. For the same reason, the gel fraction of the adhesive layer is preferably in the range of 30 to 85%.

In the adhesive composition of the present invention, the adhesive composition is formed into a layer on a first film made of a cyclic polyolefin resin, and the formed layered adhesive composition (the One layer), and the peel force between the first layer and the first alkali-free glass plate after the first alkali-free glass plate is laminated on the first layer and stored at 23 ° C. for 24 hours is set as P _CO23 , this adhesive composition is formed into a layered shape on a second film made of a cyclic polyolefin resin, and is formed into a formed layered adhesive composition (second layer). When the alkali glass plate is laminated on the second layer and stored in a 50 ° C environment for 48 hours, the peeling force between the second layer and the second alkali-free glass plate is set to P _CO50 , P _CO50 and P _CO23 The ratio (P _CO50 / P _CO23 ) is 4.5 or more.

If a resin film included in an optical member such as a polarizing plate is bonded to a liquid crystal cell substrate made of an alkali-free glass through an adhesive layer composed of such an adhesive composition, it is easy to perform the optical member immediately after bonding. The so-called rework which peels and replaces a new optical member. also because After bonding, the peeling force is increased by heating. Therefore, it is preferable that optical members such as a polarizing plate can be more strongly bonded to a liquid crystal cell or the like.

From the viewpoint of being easily bonded to a liquid crystal cell substrate made of an alkali-free glass, etc., P _CO23 is usually 0.5N / 25mm or more, usually 5N / 25mm or less, and preferably 3N / 25mm or less. From the viewpoint of being able to _{adhere to the} liquid crystal cell with sufficient peeling force even at a higher temperature, the P _CO50 is usually 2N / 25mm or more, usually 20N / 25mm or less, and preferably 18N / 25mm or less.

<Optical member with adhesive layer>

The adhesive layer of the present invention can be suitably used as an adhesive layer for bonding an optical member such as a polarizing plate and a liquid crystal cell substrate, particularly a liquid crystal cell substrate made of an alkali-free glass. The optical member with an adhesive layer of the present invention can be formed by laminating an adhesive layer on an optical member such as a polarizing plate, or by laminating and bonding other optical members on the outside of the adhesive layer. Successor.

[1] First embodiment

A preferred embodiment of the optical member with an adhesive layer of the present invention includes a resin film as an optical member and an adhesive layer laminated on at least one side thereof. Examples of the resin film include optical films such as a polarizer, a protective film, and a retardation film, and surface protective films which are bonded to an optical film belonging to a protected body, and are used to protect the surface from damage and pollution. (protect film).

Polarizers are thin films that have the function of extracting linearly polarized light from incident natural light. Suitable examples are iodine and dichroic dyes. A chromic pigment adsorbed and aligned on a uniaxially stretched polyvinyl alcohol resin film. The thickness of the polarizer is not particularly limited, but is usually 0.5 to 35 μm.

The protective film can be made of a resin having translucency (preferably optically transparent) such as a chain polyolefin resin (polypropylene resin, etc.), a cyclic polyolefin resin (norbornene resin, etc.) ) And other polyolefin resins; cellulose resins such as cellulose triacetate and cellulose diacetate; polyester resins; polycarbonate resins; (meth) acrylic resins; polystyrene resins; polyethers Ether ketone resin; a film made of thermoplastic resin such as polyfluorene resin.

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

The cyclic polyolefin resin is a general term for a resin polymerized by using a cyclic olefin as a polymerization unit. Specific examples of cyclic polyolefin resins include ring-opening (co) polymers of cyclic olefins, addition polymers of cyclic olefins, and cyclic olefins and chain olefins such as ethylene and propylene. Copolymers (typically random copolymers), graft polymers obtained by modifying these with unsaturated carboxylic acids or derivatives thereof, and hydrides thereof. In particular, norbornene-based resins using norbornene-based monomers such as norbornene and polycyclic norbornene-based monomers as cyclic olefins can be suitably used.

Examples of the partially or completely esterified cellulose resin-based cellulose include cellulose acetate, propionate, butyrate, and mixed esters thereof. In particular, cellulose triacetate, cellulose diacetate, cellulose acetate propionate, cellulose acetate butyrate, and the like can be suitably used.

Polyester-based resins are resins other than the above-mentioned cellulose-based resins having an ester bond, and are generally composed of a polycondensate of a polycarboxylic acid or a derivative thereof and a polyhydric alcohol. As the polycarboxylic acid or its derivative, a dicarboxylic acid or its derivative can be used, and examples thereof include terephthalic acid, isophthalic acid, dimethyl terephthalate, and dimethyl naphthalate. . As the polyol, a diol can be used, and examples thereof include ethylene glycol, propylene glycol, butylene glycol, neopentyl glycol, and cyclohexanedimethanol.

Specific examples of the polyester resin include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, and polyterephthalic acid. Malonate, polynaphthalate, polycyclohexane dimethyl terephthalate, cyclohexane dimethyl polynaphthalate.

Polycarbonate resins are composed of polymers in which monomer units are bonded through a carbonate group. The polycarbonate-based resin may be a resin called a modified polycarbonate obtained by modifying a polymer skeleton, a copolymerized polycarbonate, or the like.

The (meth) acrylic resin may be a polymer having methacrylate as a main monomer, and preferably a copolymer obtained by copolymerizing a small amount of other comonomer components with it. The (meth) acrylic resin is more preferably a copolymer of methyl methacrylate and methyl acrylate, and it may be further copolymerized with a third monofunctional monomer.

Examples of the third monofunctional monomer include, for example, ethyl methacrylate, butyl methacrylate, cyclohexyl methacrylate, phenyl methacrylate, benzyl methacrylate, and methacrylic acid. 2-ethyl Hexyl ester, 2-hydroxyethyl methacrylate and other methacrylates other than methyl methacrylate; such as ethyl acrylate, butyl acrylate, cyclohexyl acrylate, phenyl acrylate, benzyl acrylate, acrylic acid 2-ethylhexyl ester, 2-hydroxyethyl acrylate and other acrylates other than methyl acrylate; such as 2- (hydroxymethyl) acrylate, 2- (1-hydroxyethyl) acrylate, 2 -Hydroxyalkyl acrylates such as ethyl (hydroxymethyl) acrylate and butyl 2- (hydroxymethyl) acrylate; unsaturated acids such as methacrylic acid and acrylic acid; halogenated benzenes such as chlorostyrene and bromostyrene Ethylene; Substituted styrenes such as vinyl toluene and α-methylstyrene; Unsaturated nitriles such as acrylonitrile and methacrylonitrile; Unsaturated acid anhydrides such as maleic anhydride and citraconic anhydride; Such as phenyl-cis-butene difluorene imine, cyclohexyl-cis-butene difluorene and other unsaturated fluorene imines. The third monofunctional monomer may be used alone or in combination of two or more.

The (meth) acrylic resin may be further copolymerized with a polyfunctional monomer. Examples of the polyfunctional monomer include, for example, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, and tetraethyl Diethylene glycol di (meth) acrylate, nonaethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, etc. Use ethylene or methacrylic acid to separate ethylene glycol or its oligomer Esterified at both ends of hydroxyl groups; Esterified at both ends of propylene glycol or its oligomers using acrylic or methacrylic acid; such as neopentyl glycol di (meth) acrylate, hexanediol di (Meth) acrylates, butanediol di (meth) acrylates, etc., obtained by esterifying hydroxyl groups of diols with acrylic acid or methacrylic acid; bisphenol A, alkylene oxide adducts of bisphenol A , Or use acrylic or methacrylic Those obtained by esterifying the hydroxyl groups at both ends of the halogen substituents; those obtained by esterifying polyhydric alcohols such as trimethylolpropane and neopentyl tetraol using acrylic acid or methacrylic acid; The epoxy group of epoxy ester or glycidyl methacrylate is obtained by ring-opening addition of these terminal hydroxyl groups; the epoxy group of glycidyl acrylate or glycidyl methacrylate is added to succinic acid, Diacids, terephthalic acid, phthalic acid, halogen substituted products such as dibasic acids, and alkylene oxide adducts, etc .; Such as divinylbenzene and other aromatic divinyl compounds. In particular, ethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, and neopentyl glycol dimethacrylate can be suitably used.

The (meth) acrylic resin may be modified to further perform a reaction between the functional groups of the copolymer. Examples of such a responder include a de-methanol condensation reaction within a polymer chain of a methyl group of methyl acrylate and a hydroxyl group of methyl 2- (hydroxymethyl) acrylate, and a carboxyl group of acrylic acid and 2- (hydroxymethyl) ) Dehydration condensation reaction in the polymer chain of the hydroxyl group of methyl acrylate. The (meth) acrylic resin may have any one of a glutarimide derivative, a glutaric anhydride derivative, or a lactone ring structure.

The (meth) acrylic resin may contain additives as needed. Examples of the additive include a slip agent, an anti-caking agent, a heat stabilizer, an antioxidant, an antistatic agent, a light resistance agent, an impact resistance improver, and a surfactant.

(Meth) acrylic resin may contain acrylic rubber pellets from the viewpoints of film forming properties and impact resistance of the film child. The acrylic rubber particles are particles containing an elastic polymer mainly composed of acrylate as an essential component, and examples thereof include those having a single-layer structure consisting essentially of the elastic polymer, and designing the elastic polymer. It is a multi-layer structure with 1 layer. Examples of the elastic polymer include a crosslinked elastic copolymer obtained by copolymerizing an alkyl acrylate as a main component and another copolymerizable vinyl monomer and a crosslinkable monomer. Examples of the alkyl acrylate which is a main component of the elastic polymer include those having an alkyl group having a carbon number of about 1 to 8 such as methyl acrylate, ethyl acrylate, n-butyl acrylate, and 2-ethylhexyl acrylate. Acrylic acid having an alkyl group having 4 or more carbon atoms can be suitably used. Examples of other vinyl monomers that can be copolymerized with the alkyl acrylate include compounds having one polymerizable carbon-carbon double bond in the molecule, and more specifically, such as methyl methacrylate, etc. Methacrylates, aromatic vinyl compounds such as styrene, vinyl cyanide compounds such as acrylonitrile, and the like. Examples of the crosslinkable monomer include crosslinkable compounds having at least two polymerizable carbon-carbon double bonds in the molecule, and more specifically, such as ethylene glycol di (meth) acrylate, (Meth) acrylates of polyhydric alcohols such as butanediol di (meth) acrylate; alkenyl esters of (meth) acrylic acid such as allyl (meth) acrylate; divinylbenzene;

A laminate of a film made of a (meth) acrylic resin containing no rubber particles and a film made of a (meth) acrylic resin containing rubber particles can also be used as the protective film.

The retardation film is an optical film exhibiting optical anisotropy, and may be a resin usable from the above-mentioned protective film and, for example, a polyvinyl alcohol resin, a polyarylate resin, a polyimide resin, or a polyether. Resin films consisting of fluorene-based resin, polyvinylidene fluoride / polymethyl methacrylate-based resin, liquid crystal polyester-based resin, ethylene-vinyl acetate copolymer saponification, and polyvinyl chloride-based resin extend to 1.01 to The stretched film obtained about 6 times. In particular, it is preferable that the polycarbonate resin film, the cyclic polyolefin resin film, the (meth) acrylic resin film, or the cellulose resin film is uniaxially stretched or biaxially stretched. In this specification, a zero retardation film is also included in the retardation film (however, it can also be used as a protective film). In addition, thin films called uniaxial retardation films, wide viewing angle retardation films, low photoelastic modulus retardation films, and the like can also be applied as retardation films.

The zero-hysteresis film refers to a film in which the in-plane retardation value R _e and the thickness direction retardation value R _th are both -15 to 15 nm. This retardation film system can be suitably used for a liquid crystal display device in an IPS mode. The in-plane retardation value R _e and the thickness direction retardation value R _th are both preferably -10 to 10 nm, and more preferably both -5 to 5 nm. Referred to in this plane retardation value of R _e and the thickness direction retardation R _th, it means the wavelength of 590nm.

The in-plane phase difference value R _e and the thickness direction phase difference value R _th are each defined by the following formula: R _e = (n _x -n _y ) × d R _th = [(n _x + n _y ) / 2-n _z ] × d, where n _x is the refractive index in the slow axis direction (x-axis direction) of the film plane, and n _y is the fast axis direction in the film plane (y-axis direction orthogonal to the x-axis in the plane) The refractive index, n _z is the refractive index in the thickness direction of the film (the z-axis direction perpendicular to the film surface), and d is the thickness of the film.

For the zero-lag film, for example, a polyolefin resin such as a cellulose resin, a chain polyolefin resin, and a cyclic polyolefin resin; a polyethylene terephthalate resin or a (meth) acrylic resin can be used. The formed resin film. Since it is easy to control the phase difference value and it is also easy to obtain, a cellulose resin, a polyolefin resin, or a (meth) acrylic resin can be used suitably especially. For example, a (meth) acrylic resin layer can be laminated | stacked on the one or both surfaces of the retardation display layer which consists of resin different from (meth) acrylic resin, and it can also be set as a retardation film.

In addition, a thin film in which optical anisotropy is developed by coating / alignment of a liquid crystalline compound, and a thin film in which optical anisotropy is developed by coating of an inorganic layered compound can also be used as a retardation film. This type of retardation film is called a temperature-compensated retardation film, and it is also formed by oblique alignment of a rod-shaped liquid crystal sold by JX Nippon Nippon Stone Co., Ltd. under the trade name "NH FILM". Films; films made by obliquely aligning disc-shaped liquid crystals sold under the trade name "WV FILM" by Fuji FILM (stock); fully biaxially-aligned types sold by Sumitomo Chemical (stock) under the trade name "VAC FILM" Film; similarly biaxially oriented film sold by Sumitomo Chemical Co., Ltd. under the trade name "new VAC FILM".

On the other hand, the surface protection film is a film used for the purpose of protecting the surface of the optical film and the like that are to be protected from damage and pollution, such as a polarizer, a protective film, and a retardation film that are optical members for a liquid crystal display device. Various optical films, such as light-diffusing sheets and reflective sheets, are usually circulated in a state where the surface protective film is bonded to the surface (when there is an adhesive layer on one side, it is on the side opposite to the adhesive layer). . After the optical film is bonded to a liquid crystal cell or the like, the surface protective film is usually peeled off and removed.

Examples of the base material of the surface protective film include polyolefin resins such as polyethylene, polypropylene, and polymethylpentene; for example, polyvinyl fluoride, polyvinylidene fluoride, and polyvinyl fluoride Fluorinated polyolefin resins such as ethylene, etc .; such as polyethylene naphthalate, polyethylene terephthalate, polybutylene terephthalate, polyethylene terephthalate / m-benzene Polyester resins such as diformate copolymers; Polyamides such as nylon 6, nylon 6,6; polyvinyl chloride, vinyl chloride-vinyl acetate copolymers, ethylene-vinyl acetate copolymers, ethylene- Ethylene polymers such as vinyl alcohol copolymers, polyvinyl alcohol, and vinylylon; cellulose resins such as cellulose triacetate, cellulose diacetate, and cellophane; such as polymethyl methacrylate, (Meth) acrylic resins such as polyethyl methacrylate, polyethyl acrylate, polybutyl acrylate; and thermoplastic resins such as polystyrene, polycarbonate, polyarylate, and polyimide The film. The resin film is an optical member with an adhesive layer of the present invention, which is a surface protective film, and is formed by placing an adhesive layer on the substrate.

In the optical member with an adhesive layer of this embodiment, it is preferable that the above-mentioned release film is pasted on the surface of the adhesive layer in advance, and it is preferably temporarily protected until use. The optical member with an adhesive layer of this embodiment to which a release film is attached can form an adhesive layer by applying an adhesive composition on the release film, and then laminate a resin film on the obtained adhesive. Layer method; and a method of coating an adhesive composition on a resin film to form an adhesive layer, and attaching a release film to the adhesive surface thereof While manufacturing.

The optical member with an adhesive layer of this embodiment is an optical member with an adhesive layer after being stored in an alkali-free glass plate in a state of being laminated with an adhesive layer and having a temperature of 23 ° C. for 24 hours. The peeling force between the member and the alkali-free glass is set to P ₂₃ , and the adhesive is attached after storage for 48 hours in an environment where the alkali-free glass plate is laminated with the adhesive layer constituting it and the temperature is 50 ° C. When the peeling force between the optical member of the layer and the alkali-free glass is P ₅₀ , the ratio of P ₅₀ to P ₂₃ (P ₅₀ / P ₂₃ ) is 4.5 or more, preferably 5.0 or more, and usually 20 or less. When the ratio of P ₅₀ to P ₂₃ (P ₅₀ / P ₂₃ ) is within the above range, the so-called reworking system becomes easy, and the peeling force is increased by heating after bonding, so that optical devices such as polarizing plates can be used. The member is more firmly bonded to a liquid crystal cell substrate made of alkali-free glass.

From the viewpoint of being easily attached to an alkali-free glass liquid crystal cell substrate or the like, P ₂₃ is usually 0.5 N / 25 mm or more, usually 5 N / 25 mm or less, and preferably 3 N / 25 mm or less. From the viewpoint of being able to adhere to the liquid crystal cell with sufficient peeling force even at a higher temperature, P ₅₀ is usually 2N / 25mm or more, usually 20N / 25mm or less, and preferably 15N / 25mm or less.

[2] Second Embodiment

Another preferred embodiment of the optical member with an adhesive layer of the present invention is a laminated body comprising a resin film and an adhesive layer laminated on at least one side thereof. The laminated body of the resin film is preferably a laminated body of an optical film selected from optical films such as a polarizer, a protective film, and a retardation film. A typical example of the laminated body of an optical film is a polarizing plate. Adhesive in this embodiment In the optical member of the layer, it is also preferable to attach a release film on the surface of the adhesive layer in advance, and temporarily adhere and protect it until use.

Examples of the polarizing plate include a linear polarizing plate which has a property of absorbing linearly polarized light having a vibrating surface in a certain direction of the incident film surface and transmitting linearly polarized light having a vibrating surface orthogonal thereto; A polarized light separating plate having the property of reflecting linearly polarized light having a vibrating surface in a certain direction of the incident film surface and transmitting the linearly polarized light having a vibrating surface orthogonal to the polarizing plate; and an elliptical polarizing plate which is a retardation film Laminated on a linear polarizer; etc.

The linear polarizer generally has a configuration in which the above-mentioned protective film is bonded to one or both sides of the polarizer. When the protective film is bonded to both sides of the polarizer, an adhesive layer can be formed on at least one surface of the protective film. When the protective film is bonded only to one side of the polarizer, an adhesive layer can be formed on the surface of the polarizer (the surface on which the protective film is not bonded). The elliptically polarizing plate is obtained by laminating a retardation film on a linear polarizing plate. However, the linear polarizing plate usually has the same structure as the above. When the adhesive layer is laminated on the elliptically polarizing plate, the adhesive layer is usually laminated on the retardation film side.

A specific example of an optical member with an adhesive layer when the optical member is a polarizing plate will be described with reference to the drawings. In the example shown in FIG. 1, a protective film 3 having a surface treatment layer 2 is attached to one surface of a polarizer 1 with a surface opposite to the surface treatment layer 2 to constitute a polarizing plate 10. The adhesive layer 20 is provided on the surface of the polarizer 1 on the side opposite to the protective film 3 to form a polarizing plate (an optical member with an adhesive layer) 25 with an adhesive layer. This adhesive layer 20 can be a surface opposite to the polarizing plate 10 The bonding to the glass substrate 30 will be described later.

The polarizing plate 25 with an adhesive layer shown in FIG. 2 is the same as FIG. 1 except that the polarizing plate 10 includes the second protective film 4 attached to the other side of the polarizer 1. The adhesive layer 20 is laminated on the outer surface of the second protective film 4. The polarizing plate 25 with an adhesive layer shown in FIG. 3 is the same as FIG. 1 except that the polarizing plate 10 is a retardation film 7 attached to the other side of the polarizer 1 through an interlayer adhesive 8. The polarizing plate 25 with an adhesive layer shown in FIG. 4 is the same as FIG. 2 except that the polarizing plate 10 is a retardation film 7 attached to the outer surface of the second protective film 4 through the interlayer adhesive 8. . In the examples shown in FIGS. 3 and 4, the adhesive layer 20 is attached to the retardation film 7.

The surface treatment layer 2 formed on the surface of the protective film 3 can be a hard coat layer, an anti-glare layer, an anti-reflection layer, an antistatic layer, or the like. A plurality of layers can be provided among these. As the examples shown in FIGS. 3 and 4, when the polarizing plate 10 includes a retardation film 7 and a small-to-medium-sized liquid crystal display device, a suitable example of the retardation film 7 can be a 1/4 wavelength plate. . At this time, the absorption axis of the polarizer 1 and the slow axis of the retardation film 7 are usually arranged to intersect at approximately 45 degrees. However, depending on the characteristics of the liquid crystal cell, the angle may be staggered from 45 degrees to some extent. situation. On the other hand, in the case of a large-scale liquid crystal display device such as a television, for the purpose of phase difference compensation and viewing angle compensation of a liquid crystal cell, a phase difference film 7 having various phase difference values can be used in accordance with the characteristics of the liquid crystal cell. At this time, it is usually arranged such that the absorption axis of the polarizer 1 and the slow axis of the retardation film 7 are in a substantially orthogonal or substantially parallel relationship. When the retardation film 7 is configured by a 1/4 wavelength plate, Use a uniaxial or biaxial stretch film. When the retardation film 7 is provided for the purpose of phase difference compensation and viewing angle compensation of the liquid crystal cell, in addition to the uniaxial or biaxially stretched film, it is possible to align not only uniaxial or biaxially stretched films but also the thickness direction. Films formed by applying retardation display materials such as liquid crystals to a support film and fixing the alignment thereof, and the like, which are called optical compensation films, are used as the retardation film 7.

The interlayer adhesive 8 in FIGS. 3 and 4 is generally a general (meth) acrylic adhesive. Of course, the adhesive layer of the present invention can also be used. As described above, when the absorption axis of the polarizer 1 and the slow axis of the retardation film 7 are arranged in a substantially orthogonal or substantially parallel relationship, it is also possible to use an adhesive instead of the interlayer adhesive 8. Examples of the adhesive include a water-based adhesive composed of an aqueous solution or an aqueous dispersion, and exhibiting adhesive force by evaporating water belonging to a solvent; and ultraviolet curing that exhibits adhesive force by curing by ultraviolet irradiation. Type adhesive. The polarizer 1 and the protective films 3 and 4 are usually bonded together using an adhesive.

[3] Third Embodiment

According to still another preferred embodiment of the optical member with an adhesive layer of the present invention, it is on the outside of the adhesive layer in the optical member with an adhesive layer of the first or second embodiment described above, and is further laminated and bonded to other Made of optical components. The other optical member is preferably a glass substrate. FIGS. 1 to 4 show the case where the polarizing plate with an adhesive layer of the second embodiment is bonded to the glass substrate 30.

Examples of the glass substrate 30 include liquid crystal cells. Glass substrates, anti-glare glasses, sunglasses glasses, and the like. Examples of the material of the glass substrate 30 include soda-lime glass, low-alkali glass, and alkali-free glass. In particular, the glass substrate is preferably a glass substrate with a liquid crystal cell.

Liquid crystal cells usually have polarizing plates laminated on both sides through an adhesive layer, but among these polarizing plates, only the polarizing plate disposed on the front side (viewing side) of the liquid crystal cell can be the adhesive layer of the present invention. Polarizing plate; only the polarizing plate arranged on the back side (backlight side) of the liquid crystal cell is the polarizing plate with an adhesive layer of the present invention; or both of them are polarizing light with the adhesive layer of the present invention board. The driving method of the liquid crystal cell may be any of the methods well-known previously. The polarizing plate disposed on the back side (backlight side) does not usually include the surface treatment layer 2. Various optical films known to be arranged on the back side of the liquid crystal cell, such as a brightness enhancement film, a light-condensing film, and a diffusion film, can also be provided on the outside of the polarizing plate arranged on the back side.

An optical member with an adhesive layer, such as a polarizing plate with an adhesive layer, can be suitably used for a liquid crystal display device. The liquid crystal display device can be suitably used as, for example, a personal computer including a notebook, a desktop, a personal digital assistant (PDA: Personal Digital Assistant), various portable devices such as a smart phone, a tablet terminal, and a television; Monitors for automobiles; electronic dictionaries; digital cameras; digital video cameras; desktop computers; liquid crystal display devices for clocks and the like.

[Example]

Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples, but the present invention is not limited to these examples. In the following, "parts" and "%" that indicate the amount or content of use are as long as they are not specifically noted. Volume benchmark.

<Production Examples 1 to 3: Production of (meth) acrylic resin (A) for adhesive layer>

In a reaction vessel equipped with a cooling tube, a nitrogen introduction tube, a thermometer, and a stirrer, 120 parts of ethyl acetate was added, and the air in the apparatus was replaced with nitrogen to be oxygen-free, and then the internal temperature was raised to 75 ° C. A total amount of a solution obtained by dissolving 0.05 part of azobisisobutyronitrile (polymerization initiator) in 5 parts of ethyl acetate was added, and the composition shown in Table 2 was maintained while maintaining the internal temperature at 74 to 76 ° C. The monomer mixture was dropped into the reaction system over 2 hours. Furthermore, the reaction was completed by keeping the internal temperature at 74 to 76 ° C for 5 hours. Finally, ethyl acetate was added and adjusted so that the concentration of the (meth) acrylic resin was 40%, to prepare an ethyl acetate solution of the (meth) acrylic resin (A).

The weight average molecular weight (Mw), number average molecular weight (Mn), and glass transition temperature (Tg) of the (meth) acrylic resin (A) obtained in Production Examples 1 to 3 were measured. Mw and Mn are connected in series by using a total of 5 "Shodex GPC KF-802" made of 4 "TSKgel XL" made by TOSOH (share) and 1 "Showho Denko" (made by) The ground connection was arranged as a column in a GPC device, and tetrahydrofuran was used as the eluent. The measurement was performed under standard polystyrene conversion conditions at a sample concentration of 5 mg / mL, a sample introduction amount of 100 μL, a temperature of 40 ° C, and a flow rate of 1 mL / minute. . Tg is measured using a differential scanning calorimeter (DSC) "EXSTAR DSC6000" manufactured by SII Nano Technology Co., Ltd. under a nitrogen atmosphere. The measurement is performed under the conditions of a range of -80 to 50 ° C and a heating rate of 10 ° C / min. The monomer composition (% by weight) of the monomer mixture used and the Mw, molecular weight distribution Mw / Mn, and Tg of the (meth) acrylic resin (A) obtained in Production Examples 1 to 3 are summarized in Table 2. .

The abbreviations in the column of "monomer composition" in Table 2 mean the following monomers.

BA: n-butyl acrylate, MA: methyl acrylate, PEA: 2-phenoxyethyl acrylate, PEA2: 2- (2-phenoxyethoxy) ethyl acrylate, HEA: 2-hydroxyethyl acrylate BMAA: butoxymethacrylamide, AA: acrylic acid.

<Examples 1 to 10 and Comparative Example 1>

(1) Preparation of adhesive composition

The cross-linking agent (B) and compound shown in Table 3 are shown in Table 3 with respect to 100 parts by weight of the solid content of the (meth) acrylic resin (A) obtained in the production example. (C) and the silane compound (E) were each mixed in an amount (parts by weight) shown in Table 3, and ethyl acetate was added so that the solid content concentration became 28% by weight to prepare a solution of the adhesive composition. The blending amount of each blending ingredient shown in Table 3 is the weight part of the active ingredient contained in the case where the product used contains a solvent or the like.

The details of each of the compounding components shown in Table 3 by abbreviations are as follows.

(Meth) acrylic resin (A) Production Example 1: (meth) acrylic resin (A) and (meth) acrylic resin (A) obtained in Production Example 1 Production Example 2: Production Example 2 (Meth) acrylic resin (A) and (meth) acrylic resin (A) obtained Production Example 3: (meth) acrylic resin (A) and B1: Toluene obtained in Production Example 3 Ethyl acetate solution of trimethylolpropane adduct of isocyanate (solid content concentration 75%), "CORONATE L" obtained from POLYURETHANE (stock), C1: sodium acetate: obtained from Wako Pure Chemical Industries (stock) (The adhesive composition is dissolved in ethanol to prepare a 0.5% by weight solution and added), C2: "AM-230G" (the following formula: obtained from Shin Nakamura Chemical Industry Co., Ltd.)

(Methoxylated polyethylene glycol acrylate shown), C3: "AM-130G" obtained from Shin Nakamura Chemical Industry Co., Ltd. (the following formula:

(Methoxylated polyethylene glycol acrylate shown), C4: "M-130G" (the following formula:

(Methoxylated polyethylene glycol methacrylate), C5: "M-230G" (the following formula:

(Methoxylated polyethylene glycol methacrylate), S1: 3-glycidoxypropyltrimethoxysilane, and "KBM403" obtained from Shin-Etsu Chemical Industry Co., Ltd.

(2) Manufacturing of adhesive layer

Each adhesive composition prepared in the above (1) was applied using an applicator so that the thickness after drying was 20 μm. The release film [PLR-382051 "obtained from LINTEC (stock) was released from the release film made of polyethylene terephthalate film, and was dried at 100 ° C for 1 minute to produce adhesion. Adhesive layer (adhesive sheet).

(3) Manufacturing of polarizing plate with adhesive layer

A 50 μm-thick first protective film made of a cyclic polyolefin resin was bonded to one side of a polarizer having a thickness of 23 μm, which was formed by iodine adsorption and alignment with a uniaxially-stretched polyvinyl alcohol film through an adhesive. In addition, a second protective film with a thickness of 80 μm made of (meth) acrylic resin was bonded to the other surface using an adhesive different from the above to produce a polarizing plate. Next, the outer surface of the first protective film is corona-treated, and the surface of the adhesive layer (adhesive layer) on the opposite side to the separation film (adhesive layer) made in the above (2) is attached to a laminator After the corona-treated surface, it was aged under the conditions of a temperature of 23 ° C. and a relative humidity of 65% to obtain a polarizing plate with an adhesive layer.

(4) Evaluation of durability

After the separation film is peeled off from the polarizer with the adhesive layer made in the above (3), the adhesive layer is attached to the glass substrate for liquid crystal cells so as to become crossed Nicol [CORNING Corporation "Eagle XG" produced on both sides to produce evaluation samples. The following three types of durability tests were performed using this sample.

[Durability test]

． Heat resistance test for 1000 hours under dry conditions at 80 ° C. 1000 hours at 60 ° C and 90% relative humidity Moisture and heat resistance test. The operation of holding for 30 minutes under dry conditions at a temperature of 80 ° C and 30 minutes under dry conditions at a temperature of -40 ° C was set as one cycle, and the heat shock (HS) test was repeated for 500 cycles.

The samples after each test were visually observed, and the durability was evaluated in accordance with the following evaluation criteria. The results are shown in Table 4.

A: No appearance change such as floating, peeling, foaming can be observed at all, B: No appearance change such as floating, peeling, foaming can be observed, C: Many appearance changes such as lifting, peeling, foaming can be observed , D: Changes in appearance such as floating, peeling, and foaming can be noticeably observed.

(5) Evaluation of reworkability

The polarizing plate with an adhesive layer prepared in the above (3) was cut into a test piece having a size of 25 mm × 150 mm. Next, after the separation membrane was peeled off from the test piece, the adhesive layer was attached to a glass substrate for liquid crystal cells ["Eagle XG" by Corning Corporation], and the temperature was 50 ° C and the pressure was 5 kg / cm ² (490.3 kPa ) For autoclave treatment for 20 minutes. Next, after holding in an oven at 50 ° C for 50 hours, the test piece attached to the glass substrate together with the adhesive layer was subjected to a stretching speed of 300 mm / minute under the environment of a temperature of 23 ° C and a relative humidity of 50%. The peeling test was performed in a 180 ° direction (a direction in which the polarizing plate was peeled off and turned over and parallel to the glass substrate surface). The state of the surface of the glass substrate after the peeling test was visually observed, and reworkability was evaluated in accordance with the following evaluation criteria. The results are shown in Table 4.

A: Blur and residue are not observed at all on the surface of the glass plate, B: Blur and residue are almost not observed on the surface of the glass plate, C: Almost no residue is observed on the surface of the glass plate, but can be observed To the blur, D: A residue can be observed on the surface of the glass plate.

(6) Evaluation of peeling force of an optical member with an adhesive layer

A test piece having a width of 25 mm and a length of 150 mm was cut from the polarizer with the adhesive layer produced in the above (3). Next, after the separation membrane was peeled off from the test piece, the adhesive layer was attached to a glass substrate for a liquid crystal cell using a sticking device [trade name "Lamipacker" made by Fujipla Co., Ltd. [trade name "EAGLE XG"]. , Obtained from CORNING, alkali-free glass plate]. The obtained glass substrate-attached test piece (the optical member with an adhesive layer attached to the glass substrate) was pressed in an autoclave at a temperature of 50 ° C. and a pressure of 5 kgf / cm ² (490.3 kPa) for 20 minutes. Furthermore, they were left to stand under the conditions of a temperature of 23 ° C for 24 hours and under the conditions of a temperature of 50 ° C for 48 hours. The sample after standing was chucking in a tensile tester ["AUTOGRAPH AGS-X" manufactured by Shimadzu Corporation], and attached to an environment at a temperature of 23 ° C and a relative humidity of 55%. The test piece of the glass substrate together with the adhesive layer was peeled in a direction of 180 ° at a tensile speed of 300 mm / min. At this time, the measured peeling strength was evaluated as a peeling force (peeling force between a test piece (adhesive layer) and an alkali-free glass plate). Here, the peeling force under the conditions of storage for 24 hours in an environment at a temperature of 23 ° C. is P ₂₃ , and the peeling force under the conditions of storage for 48 hours in an environment at a temperature of 50 ° C. is P ₅₀ . The results are shown in Table 4. Here, P ₂₃ and P ₅₀ are equivalent to P _CO23 and P _CO50 described above.

1‧‧‧Polarizer

2‧‧‧ surface treatment layer

3‧‧‧ protective film

10‧‧‧ polarizing plate

20‧‧‧ Adhesive layer

25‧‧‧ polarizing plate with adhesive layer

30‧‧‧ glass substrate

Claims (9)

An optical member with an adhesive layer includes an optical member and an adhesive layer laminated on the optical member. The optical member with the adhesive layer is: when the optical member is laminated through the adhesive layer, After the alkali-free glass plate is stored in an environment at a temperature of 23 ° C for 24 hours, the peeling force between the aforementioned optical member with an adhesive layer and the alkali-free glass is set to P ₂₃ , and the laminated member is laminated through alkali glass plate and kept at ambient temperature 50 ℃ peel force between the optical member attached to the adhesive layer after 48 hours of non-alkali glass is set to _50, the ratio of the P P ₅₀ and P _{23 is} the sum ( P ₅₀ / P ₂₃ ) is 4.5 or more. The optical member with an adhesive layer according to item 1 of the scope of patent application, wherein the aforementioned P ₂₃ is 0.5 N / 25 mm or more. The optical member with an adhesive layer according to item 1 or 2 of the patent application scope, wherein the adhesive layer is composed of a structural unit containing a (meth) acrylic monomer derived from a hydroxyl group, and the composition The (meth) acrylic resin (A) is an adhesive composition containing more than 3.5 weight% of units. The optical member with an adhesive layer according to any one of claims 1 to 3, wherein the adhesive composition contains a cross-linking catalyst (C-1) and a compound containing an alkoxy group. (C-2). The optical member with an adhesive layer according to item 4 of the scope of patent application, wherein the adhesive composition further contains an isocyanate-based crosslinking agent (B-1). The optical member with an adhesive layer according to any one of claims 3 to 5, wherein the adhesive composition further contains an ionic compound (D). The optical member with an adhesive layer as described in any one of claims 3 to 6, wherein the adhesive composition further comprises a silane compound (E). A laminated optical member is formed by laminating an alkali-free glass plate on the adhesive layer side of the optical structure with an adhesive layer described in any one of the claims 1 to 7 of the application. An adhesive composition formed on a first film made of a cyclic polyolefin resin and formed into a layered state. A state in which a first alkali-free glass plate is laminated on the formed first layer is 23 ° C. The peeling force between the first layer and the first alkali-free glass plate after storage for 24 hours under the environment is set to _PCO23 , and the layer is formed on a second film made of a cyclic polyolefin resin. The peeling force between the second layer and the second alkali-free glass plate after the second alkali-free glass plate was laminated on the formed second layer and stored at 50 ° C. for 48 hours was set. _P CO50, the ratio of the _P CO50 of the preceding _P CO23 _(P CO50 / P CO23) of 4.5 or more.