KR102047552B1 - Optical film and use thereof - Google Patents

Abstract

An optical film composed of an acrylic resin film having an easy adhesive layer formed on a surface thereof, and providing an optical film having improved adhesion to a functional coating layer.
It is set as the optical film which has the easily bonding layer (a) containing the acrylic resin film comprised of acrylic resin (A), and polyester-acrylic composite resin (B). The optical film of this invention is suitable for use as various protective films, such as a polarizer protective film used for image display apparatuses, such as a liquid crystal display device (LCD), a retardation film, and a polarizing plate.

Description

Optical film and use thereof

The present invention relates to an optical film and its use, and more particularly, an optical film having an acrylic resin film used for a liquid crystal display device or an organic light emitting display device, and an easy adhesive layer containing a polyester-acrylic composite resin, It relates to a polarizer protective film, a polarizing plate and an image display device using the same.

The acrylic resin containing the (meth) acrylic polymer represented by polymethyl methacrylate (PMMA) is excellent in optical characteristics such as light transmittance and at the same time, in balance of mechanical strength, moldability and surface hardness. For this reason, acrylic resins are widely used as transparent materials in various industrial products including automobiles and home appliances. Recently, the use of acrylic resins for optical-related applications is increasing. In particular, the application of acrylic resins to optical films embedded in image display devices such as liquid crystal displays (LCDs), plasma display panels (PDPs), and organic EL displays (OELDs) is progressing.

For example, a polarizer protective film, which is a kind of optical film, is generally used in an image display device in a state of a polarizing plate laminated with a polarizer. The polarizing plate usually has a configuration including a polarizer and a polarizer protective film adhered to the at least one surface of the polarizer through an adhesive layer, and the most surface layer may be a functional coating layer such as a hard coat layer. Patent Document 1 discloses an optical film using an acrylic resin film having such a functional coating layer.

[Patent Document 1] Japanese Patent Application Laid-Open No. 2006-096960 (published April 13, 2006)

Patent Document 1 discloses an acrylic resin film having various functional coating layers, and a method of laminating and coating the various functional coating layers on the optical planar thermoplastic resin molded article described in Patent Document 1, or a member coated with a functional coating layer, using an adhesive or A method of laminating to an optical planar thermoplastic resin molded body through an adhesive is disclosed.

However, there was a problem that the adhesion between the acrylic resin film and the functional coating layer is insufficient.

The present invention has been made in view of the above problems, and an object of the present invention is to provide an optical film composed of an acrylic resin film having an easy adhesive layer formed thereon, and excellent in adhesion to a functional coating layer represented by a hard coat layer.

In order to solve the above problems, the present invention can solve the problems of the present invention using a known easy adhesive composition having a good affinity with a polyvinyl alcohol (PVA) -based adhesive for bonding the optical film and the polarizer. Several reviews were made. As a result, it discovered that adhesiveness of an acrylic resin film and a functional coating layer improves significantly by using the easily bonding layer containing polyester-acrylic composite resin, and came to complete this invention. That is, this invention includes the following structures.

The optical film of the present invention is an optical film having an acrylic resin film composed of an acrylic resin (A) and an easy adhesive layer (a) containing a polyester-acrylic composite resin (B).

In the optical film of the present invention, the polyester-acrylic composite resin (B) preferably has an epoxy group.

In the optical film of the present invention, the polyester-acrylic composite resin (B) further preferably has a carboxyl group.

In the optical film of the present invention, the easy adhesive layer (a) preferably contains fine particles, and the average primary particle diameter of the fine particles contained in the easy adhesive layer (a) is 300 nm or less, and the fine particles contained in the easy adhesive layer (a). The particle size distribution of is more preferably 1.0 to 1.4.

It is preferable that the optical film of this invention has a functional coating layer on the easily adhesive layer (a) containing a polyester-acrylic composite resin (B). That is, an easy adhesive layer (a) containing a polyester-acrylic composite resin (B) is formed on one principal plane of the acrylic resin film, and the acrylic resin film side surface of the easy adhesive layer (a) is formed. It is preferable that a functional coating layer is formed on the surface opposite to.

In the optical film of the present invention, it is preferable that the acrylic resin film further has an easy adhesive layer (b) on the side opposite to the easy adhesive layer (a). That is, it is preferable that the easily adhesive layer (b) is formed in the main surface on the opposite side to the surface in which the said easily adhesive layer (a) of the said acrylic resin film is formed.

As for the optical film of this invention, it is more preferable that the said easily adhesive layer (b) is a urethane resin layer.

In the optical film of the present invention, it is preferable that an adhesive layer is formed on a surface of the easy adhesive layer (b) that faces the surface of the acrylic resin film side.

In the optical film of the present invention, the acrylic resin film preferably contains a (meth) acryl polymer having a ring structure in the main chain.

The optical film of the present invention preferably has at least one member selected from the group consisting of maleic anhydride structure, N-substituted maleimide structure, glutaric anhydride structure, glutarimide structure, and lactone ring structure.

The optical film of the present invention preferably has a light transmittance of 30% or less at 380 nm.

In the optical film of the present invention, it is preferable that the acrylic resin film contains a ultraviolet absorber having a molecular weight of 600 or more.

The polarizer protective film of the present invention has the optical film of the present invention.

The polarizing plate of this invention has the said optical film of this invention.

The image display device of the present invention has the polarizing plate of the present invention.

The optical film which concerns on this invention is a structure which has the acrylic resin film comprised from the acrylic resin (A), and the easily bonding layer (a) containing a polyester-acrylic composite resin (B).

Therefore, it is possible to provide an optical film having excellent adhesion to a functional coating layer such as a hard coat layer and an improved strength, a polarizer protective film, a polarizing plate, and an image display device using the same.

1 shows an example of a first aspect of the optical film of the present invention.
2 shows an example of a second embodiment of the optical film of the present invention.
3 shows an example of a third embodiment of the optical film of the present invention.
4 shows an embodiment of a polarizing plate according to the present invention.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described in detail. Unless stated otherwise in the following description, "%" means "weight%" and "part" means "weight part", respectively. Moreover, "A-B" which shows a range shows that it is A or more and B or less.

As used herein, "resin" is a broader concept than "polymer." Resin may be comprised, for example from 1 type, or 2 or more types of polymer, and if necessary, contains materials other than a polymer, for example, an ultraviolet absorber, antioxidant, fillers, such as fillers, a compatibilizer, a stabilizer, etc. can do.

[One. Optical film]

The optical film according to the present invention has an acrylic resin film composed of an acrylic resin (A) and an easy adhesive layer (a) containing a polyester-acrylic composite resin (B). Hereinafter, the structure of the optical film which concerns on this invention in order of an acrylic resin film and an easily bonding layer is demonstrated.

(1-1.acrylic resin film)

An acrylic resin film is a film comprised from the acrylic resin (A) containing a (meth) acryl polymer. That is, an acrylic resin film is comprised from acrylic resin (A).

An acrylic resin film is obtained by shaping an acrylic resin (A). The content of the (meth) acrylic polymer in the acrylic resin (A) is generally at least 30% by weight, preferably at least 50% by weight, more preferably at least 70% by weight, particularly preferably at least 90% by weight, most preferably Preferably at least 95% by weight. The (meth) acryl polymer has excellent optical properties such as high light transmittance and low wavelength dependence of refractive index. Therefore, the acrylic resin (A) containing a (meth) acryl polymer is suitable for use as an optical film.

The (meth) acrylic polymer is a polymer having a structural unit ((meth) acrylic acid ester unit) derived from a (meth) acrylic acid ester monomer. The content of the (meth) acrylic acid ester unit in the (meth) acrylic polymer is generally at least 10% by weight, preferably at least 30% by weight, more preferably at least 50% by weight, particularly preferably at least 70% by weight.

The (meth) acrylic polymer may have a ring structure in the main chain. The cyclic structure may be, for example, by copolymerizing a monomer having a cyclic structure with a (meth) acrylic acid ester monomer or by polymerizing monomers including a (meth) acrylic acid ester monomer and then carrying out a cyclization reaction to thereby obtain a (meth) acrylic polymer. Is introduced into the main chain. When the polymer has a ring structure in the main chain, the polymer is a (meth) acrylic polymer when the sum of the content of the (meth) acrylic acid ester unit and the ring structure is 50% by weight or more.

The (meth) acrylic acid ester unit is, for example, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, n-butyl (meth) acrylate, t-butyl (meth) acrylate, (meth) N-hexyl acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, chloromethyl (meth) acrylate, 2-chloroethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 3-methacrylate (meth) acrylate It is a structural unit derived from each monomer of hydroxypropyl, (meth) acrylic acid 2,3,4,5,6-pentahydroxyhexyl, and (meth) acrylic acid 2,3,4,5-tetra hydroxypentyl.

It is preferable that the (meth) acryl polymer has a methyl (meth) acrylate unit, and in this case, the optical properties and thermal stability of the finally obtained optical film are improved. The (meth) acrylic polymer may have two or more (meth) acrylic acid ester units.

The (meth) acryl polymer may have structural units other than the (meth) acrylic acid ester unit. Such structural units are, for example, styrene, vinyl toluene, α-methyl styrene, α-hydroxy methyl styrene, α-hydroxy ethyl styrene, acrylonitrile, methacrylonitrile, ethylene, propylene, 4-methyl- It is a structural unit derived from each monomer of 1-pentene, vinyl acetate, 2-hydroxy methyl-1- butene, methyl vinyl ketone, N-vinyl pyrrolidone, and N-vinyl carbazole. The (meth) acryl polymer may have 2 or more types of these structural units. When the (meth) acrylic polymer has N-vinyl pyrrolidone units or N-vinyl carbazole units, the degree of freedom in controlling the birefringence wavelength dispersion in the optical film is improved. For example, a retardation film exhibiting wavelength dispersion (so-called reverse wavelength dispersion) in which birefringence becomes smaller (shorter absolute value of phase difference) becomes smaller as the wavelength of light becomes shorter in the visible light region.

In the case where the ring structure is introduced into the main chain by cyclization reaction after polymerization, the (meth) acryl polymer is preferably formed by copolymerization of a monomer group including a monomer having a hydroxyl group and / or a carboxylic acid group.

Monomers having hydroxyl groups are, for example, methyl 2- (hydroxymethyl) acrylate, ethyl 2- (hydroxymethyl) acrylate, isopropyl 2- (hydroxymethyl) acrylate, butyl 2- (hydroxymethyl), Methyl 2- (hydroxyethyl) acrylate, metall alcohol, allyl alcohol. Monomers having a carboxylic acid group are, for example, acrylic acid, methacrylic acid, crotonic acid, 2- (hydroxymethyl) acrylic acid and 2- (hydroxyethyl) acrylic acid.

You may use 2 or more types of these monomers. In addition, these monomers have a cyclic structure located in the main chain of the (meth) acrylic polymer by the cyclization reaction, but all of the monomers need not be changed to the cyclic structure during the cyclization reaction, and the (meth) acrylic polymer after the cyclization reaction It may have a structural unit derived from these monomers.

Preferably the weight average molecular weight of a (meth) acryl polymer is 10,000-500,000, More preferably, it is 20,000-400,000, More preferably, it is 30,000-300,000.

It is preferable that a (meth) acryl polymer has ring structure in a principal chain. It is preferable that an acrylic resin film contains the (meth) acryl polymer which has a ring structure in a principal chain. In this case, heat resistance and hardness of the optical film are improved. In addition, the ring structure of the main chain contributes to the large retardation of the acrylic resin film by stretching. This feature enables the use of the optical film of the present invention as a polarizer protective film having the function of a retardation film or a retardation film.

The ring structure which may have a (meth) acrylic polymer in the main chain is at least one member selected from, for example, an N-substituted maleimide structure, a maleic anhydride structure, a glutarimide structure, a glutaric anhydride structure, and a lactone ring structure. . The N-substituted maleimide structure is, for example, a cyclohexyl maleimide structure, a methyl maleimide structure, a phenyl maleimide structure, a benzyl maleimide structure.

In view of the heat resistance of the optical film, the ring structure includes a lactone ring structure, a cyclic imide structure (eg, N-alkyl substituted maleimide structure, glutarimide structure), a cyclic anhydride structure (eg, maleic anhydride structure, and Glutaric anhydride structure) is preferred.

In the case where the optical film of the present invention is a retardation film, the ring structure is preferably a lactone ring structure, a glutarimide structure, and a glutaric anhydride structure from the viewpoint of providing a positive retardation with respect to the film.

The following glutaric anhydride structure and glutarimide structure are shown in following formula (1).

In the formula (1), R ¹ and R ² are each independently a hydrogen atom or a methyl group, and X ¹ is an oxygen atom or a nitrogen atom. When X ¹ is an oxygen atom, R ³ does not exist, and when X ¹ is a nitrogen atom, R ³ is a hydrogen atom, a linear alkyl group having 1 to 6 carbon atoms, a cyclopentyl group, a cyclohexyl group, a benzyl group, or a phenyl group.

When X <^1> is an oxygen atom, the ring structure represented by General formula (1) becomes a glutaric anhydride structure. The glutaric anhydride structure can be formed by, for example, dealcoholization condensation of a copolymer of (meth) acrylic acid ester with (meth) acrylic acid.

When X ¹ is a nitrogen atom, the ring structure represented by the formula (1) is a glutarimide structure. A glutarimide structure can be formed by imidating a (meth) acrylic acid ester polymer with imidation agents, such as methyl amine, for example.

In the following formula (2), maleic anhydride structure and N-substituted maleimide structure are shown.

In the formula (2), R ⁴ and R ⁵ are each independently a hydrogen atom or a methyl group, and X ² is an oxygen atom or a nitrogen atom. When X ² is an oxygen atom, R ⁶ is not present, and when X ² is a nitrogen atom, R ⁶ is a hydrogen atom, a linear alkyl group having 1 to 6 carbon atoms, a cyclopentyl group, a cyclohexyl group, a benzyl group, or a phenyl group.

When X ² is an oxygen atom, the ring structure represented by the formula (2) has a maleic anhydride structure. The maleic anhydride structure can be formed by copolymerizing maleic anhydride and a (meth) acrylic acid ester, for example.

When X ² is a nitrogen atom, the ring structure represented by the formula (2) is an N-substituted maleimide structure. The N-substituted maleimide structure can be formed by, for example, polymerizing N-substituted maleimide such as phenyl maleimide and (meth) acrylic acid ester.

In addition, in each method of forming the ring structure illustrated in description of General formula (1), (2), since the polymer used for forming each ring structure all has (meth) acrylic acid ester unit as a structural unit, the said Resin obtained by the method becomes an acrylic resin.

The lactone ring structure that the (meth) acrylic polymer may have in the main chain is not particularly limited, and may be, for example, a 4 to 8 membered ring, but is preferably a 5 or 6 membered ring because of excellent stability of the ring structure. It is more preferable that it is a toric ring.

Although the lactone ring structure which is a 6-membered ring is a structure disclosed by Unexamined-Japanese-Patent No. 2004-168882, for example, the acrylic resin which has a high lactone ring content rate by the polymerization condensation reaction of a precursor is high, The structure shown by following General formula (3) is preferable because it is obtained, the polymer which has a methyl methacrylate unit as a structural unit can be used as a precursor, and the like.

In the above formula (3), R ⁷ , R ⁸ and R ⁹ are each independently a hydrogen atom or an organic residue having 1 to 20 carbon atoms. The organic residue may include an oxygen atom.

The organic residue in the formula (3) is, for example, an unsaturated aliphatic hydrocarbon group or phenyl group having 2 to 20 carbon atoms, such as an alkyl group having 1 to 20 carbon atoms, such as a methyl group, an ethyl group, or a propyl group, an ethenyl group, or a propenyl group. And an aromatic hydrocarbon group having 6 to 20 carbon atoms, such as a naphthyl group, wherein the alkyl group, the unsaturated aliphatic hydrocarbon group, and the aromatic hydrocarbon group have at least one hydrogen atom selected from a hydroxyl group, a carboxyl group, an ether group, and an ester group It may be substituted by one type of group.

Although the content rate of the said ring structure except the lactone ring structure in an acrylic resin (A) is not specifically limited, For example, it is 5 to 90 weight%, Preferably it is 10 to 70 weight%, More preferably, it is 10 to 60 % By weight, even more preferably 10 to 50% by weight.

When the acrylic resin (A) has a lactone ring structure in the main chain, the content rate of the lactone ring structure in the resin is not particularly limited, but is, for example, 5 to 90% by weight, preferably 10 to 80% by weight, More preferably, it is 10 to 70 weight%, More preferably, it is 20 to 60 weight%.

When the content rate of the ring structure in an acrylic resin (A) is excessively low, the heat resistance of a film may fall, solvent resistance, and surface hardness may be inadequate. On the other hand, when the said content rate becomes excessively large, the moldability and mechanical property of a film will fall.

The (meth) acryl polymer which has a ring structure in a principal chain can be formed by a well-known method.

The (meth) acrylic polymer having a glutaric anhydride structure in the main chain is, for example, the polymers described in Japanese Patent Application Laid-Open No. 2006-283013, Japanese Patent Application Laid-Open No. 2006-335902, and Japanese Patent Application Laid-Open No. 2006-274118. It can form by the method described in the publication.

As for the (meth) acryl polymer which has a glutarimide structure in a principal chain, Unexamined-Japanese-Patent No. 2006-309033, Unexamined-Japanese-Patent No. 2006-317560, Unexamined-Japanese-Patent No. 2006-328329, Unexamined-Japanese-Patent No. 2006-328334, It is the polymer described in Unexamined-Japanese-Patent No. 2006-337491, Unexamined-Japanese-Patent No. 2006-337492, Unexamined-Japanese-Patent No. 2006-337493, Unexamined-Japanese-Patent No. 2006-337569, and Unexamined-Japanese-Patent No. 2007-009182. It can be formed by the method.

The (meth) acrylic polymer having a maleic anhydride structure or an N-substituted maleimide structure in its main chain is, for example, the polymers described in JP-A-57-153008 and JP-A-2007-31537. It can be formed by the method described.

Examples of the (meth) acryl polymer having a lactone ring structure in the main chain thereof include JP-A-2000-230016, JP-A-2001-151814, JP-A-2002-120326, JP-A-2002-254544, Japan It is a polymer as described in Unexamined-Japanese-Patent No. 2005-146084, and can be formed by the method as described in the said publication.

The acrylic resin film may contain a thermoplastic polymer other than the (meth) acrylic polymer as long as the effect of the present invention can be obtained.

Other thermoplastic polymers include, for example, olefin polymers such as polyethylene, polypropylene, ethylene-propylene copolymers, poly (4-methyl-1-pentene); Halogenated vinyl polymers such as polyvinyl chloride, polyvinylidene chloride and polyvinyl chloride; Styrene polymers such as polystyrene, styrene-methyl methacrylate copolymer, styrene-acrylonitrile copolymer and acrylonitrile-butadiene-styrene block copolymer; Polyesters such as polyethylene terephthalate, polybutylene terephthalate and polyethylene naphthalate; Cellulose acylates such as cellulose triacetate, cellulose acetate propionate and cellulose acetate butyrate; Polyamides such as nylon 6, nylon 66 and nylon 610; Polyacetals; Polycarbonate; Polyphenylene oxides; Polyphenylene sulfide; Poly ether-ether ketones; Poly sulfone; Polyether sulfones; Polyoxy benzylene; Polyamideimide; It is rubbery polymers, such as ABS resin and ASA resin which mix | blended polybutadiene rubber or acrylic rubber.

It is preferable that the rubbery polymer has a graft portion of a composition compatible with the acrylic resin (A) on the surface, and the average particle diameter of the rubbery polymer is preferably 300 nm or less, more preferably from the viewpoint of transparency improvement when the film is used. Is 200 nm or less, even more preferably 150 nm or less.

In addition, the average particle diameter of a rubbery polymer can be measured by the method similar to obtaining the average primary particle diameter of the microparticle mentioned later.

When the acrylic resin film is a stretched film containing a styrene polymer, the positive phase difference indicated by the (meth) acrylic polymer having a ring structure in the main chain may be offset by the negative phase difference represented by the styrene polymer. Depending on the content of the styrene polymer in the acrylic resin film, the optical film of the present invention, which is a stretched film, may also be a negative polarizer protective film having a low phase difference as well as a negative phase difference film.

When an acrylic resin film contains a styrene polymer, a styrene-acrylonitrile copolymer is preferable as a styrene polymer from a compatibility with a (meth) acryl polymer. When the acrylic resin film contains ABS resin or ASA resin, depending on the content of the resin in the acrylic resin film, the optical film of the present invention, which is a stretched film, may be a positive or negative retardation film or a low retardation film, Its flexibility is also improved.

The content of the other thermoplastic polymer in the acrylic resin film is preferably 0 to 50% by weight, more preferably 0 to 40% by weight, even more preferably 0 to 30% by weight, particularly preferably 0 to 20% by weight. .

The acrylic resin film may have an ultraviolet absorbing function in a range that does not impair heat resistance, physical properties, and optical properties. Specifically, a method of using an ultraviolet absorbent monomer and / or an ultraviolet stable monomer as a monomer component when producing a (meth) acrylic polymer, or a method of blending an ultraviolet absorber and / or an ultraviolet stabilizer into the (meth) acryl polymer. There is this. Moreover, these may use these methods together, as long as there is no obstacle in the optical film containing an acrylic resin film.

Moreover, in order to maintain the said ultraviolet absorbing function, it is preferable to use together an ultraviolet absorbing monomer and an ultraviolet stable monomer, or to use an ultraviolet absorber and an ultraviolet stabilizer together. It is also preferable to use an ultraviolet absorbent and / or an ultraviolet stabilizer together with the ultraviolet absorbent monomer and / or the ultraviolet stable monomer.

As a kind of the said ultraviolet absorbing monomer, the acryl-type monomer which has a benzotriazole type compound, a benzophenone type compound, a triazine type compound, and a polymerizable unsaturated group is mentioned.

As a benzotriazole type compound, it is 2- [2'-hydroxy-5'- (meth) acryloyloxymethylphenyl] -2H-benzotriazole, 2- [2'-hydroxy-5 '-( Meta) acryloyloxyethylphenyl] -2H-benzotriazole, 2- [2'-hydroxy-5 '-(meth) acryloyloxy propylphenyl] -2H-benzotriazole, 2- [2' -Hydroxy-5 '-(meth) acryloyloxy hexylphenyl] -2H-benzotriazole, 2- [2'-hydroxy-3'-tert-butyl-5'-(meth) acryloyloxy Ethylphenyl] -2H-benzotriazole, 2- [2'-hydroxy-5 '-(β- (meth) acryloyloxyethoxy) -3'-tert-butylphenyl] -5-tert-butyl -2H-benzotriazole, 2- [2'-hydroxy-3'-methacrylaminomethyl-5 '-(1 ", 1", 3 ", 3" -tetramethyl) butylphenyl] -2H-benzo Triazoles and the like can be used.

Moreover, as a benzophenone type compound, for example, 2-hydroxy-4- [2- (meth) acryloyloxy] ethoxy benzophenone and 2-hydroxy-4- [2- (meth) acryl Yloxy] butoxybenzophenone, 2,2'-dihydroxy-4- [2- (meth) acryloyloxy] ethoxy benzophenone, 2-hydroxy-4- [2- (meth) acrylo Yloxy] ethoxy-4 '-(2-hydroxyethoxy) benzophenone, etc. can be used.

Moreover, as a triazine type compound, 4-diphenyl-6- [2-hydroxy-4- (2-acryloyloxyethoxy) -s-triazine, 2, 4-bis (2-methylphenyl), for example. ) -6- [2-hydroxy-4- (2-acryloyloxyethoxy)]-s-triazine, 2,4-bis (2-methoxyphenyl) -6- [2-hydroxy- 4- (2-acryloyloxyethoxy)]-s-triazine and the like can be used.

When using such an ultraviolet absorbing monomer, it is preferable that the ultraviolet absorbing monomer is copolymerized 0.1 to 25% by weight of all monomers, and more preferably 1 to 15% by weight. If the content is small, the contribution of improving weather resistance is low. If the content is too high, the hot water resistance and solvent resistance may be lowered or yellowing may occur.

As the ultraviolet stable monomer, a polymerizable unsaturated group bonded to a hindered amine compound may be used, and specific examples thereof include 4- (meth) acryloyloxy-2,2,6,6-tetramethylpy. Ferridine, 4- (meth) acryloylamino-2,2,6,6-tetramethylpiperidine, 4- (meth) acryloyloxy-1,2,2,6,6-pentamethylpi Ferridine, 4- (meth) acryloylamino-1,2,2,6,6-pentamethyl piperidine, 4-cyano-4- (meth) acryloylamino-2,2,6, 6-tetramethyl piperidine, 4-crotonoyloxy-2,2,6,6-tetramethyl piperidine, 4-crotonoylamino-2,2,6,6-tetramethyl piperidine, 1- (meth) acryloyl-4- (meth) acryloylamino-2,2,6,6-tetramethyl piperidine, 1- (meth) acryloyl-4-cyano-4- ( Meta) acryloylamino-2,2,6,6-tetramethyl piperidine, 1-crotonoyl-4-crotonoyloxy-2,2,6,6-tetramethyl piperidine, and the like. do.

In the case of using such an ultraviolet stable monomer, the ultraviolet stable monomer is preferably copolymerized 0.1 to 25% by weight of all monomers, more preferably 1 to 15% by weight. If the content is small, the contribution of improving weather resistance is low, and if the content is too high, the hot water resistance and solvent resistance may decrease or yellowing may occur.

As said ultraviolet absorber, a benzophenone type compound, a salicylate type compound, a benzoate type compound, a triazole type compound, a triazine type compound, etc. can be mentioned.

Examples of the benzophenone compounds include 2,4-dihydroxy benzophenone, 4-n-octyloxy-2-hydroxy benzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2 -Hydroxy-4-n-octyloxy benzophenone, bis (5-benzoyl-4-hydroxy-2-methoxy phenyl) methane, 1,4-bis (4-benzoyl-3-hydroxyphenone) -butane Etc. can be mentioned.

P-t-butylphenyl salicylate etc. are mentioned as a salicylate type compound.

Examples of the benzoate-based compound include 2,4-di-t-butylphenyl-3 ', 5'-di-t-butyl-4'-hydroxy benzoate.

Moreover, as a triazole type compound, 2,2'- methylenebis [4- (1,1,3,3- tetramethylbutyl) -6- (2H- benzotriazol-2-yl) phenol], 2- (3 , 5-di-tert-butyl-2-hydroxyphenyl) -5-chlorobenzotriazole, 2- (2H-benzotriazol-2-yl) -p-cresol, 2- (2H-benzotriazole- 2-yl) -4,6-bis (1-methyl-1-phenylethyl) phenol, 2-benzotriazol-2-yl-4,6-di-tert-butylphenol, 2- [5-chloro ( 2H) -benzotriazol-2-yl] -4-methyl-6-t-butylphenol, 2- (2H-benzotriazol-2-yl) -4,6-di-t-butylphenol, 2- (2H-benzotriazol-2-yl) -4- (1,1,3,3-tetramethylbutyl) phenol, 2- (2H-benzotriazol-2-yl) -4-methyl-6- ( 3,4,5,6-tetrahydrophthalimidylmethyl) phenol, methyl 3- (3- (2H-benzotriazol-2-yl) -5-t-butyl-4-hydroxyphenyl) propionate Reaction product of polyethylene glycol 300, 2- (2H-benzotriazol-2-yl) -6- (straight and branched dodecyl) -4-methylphenol, 2- (5-methyl-2-hydroxyphenyl) Benzotriazole, 2- [2-hydroxy-3,5-bis (α, -Dimethylbenzyl) phenyl] -2H-benzotriazole, 3- (2H-benzotriazol-2-yl) -5- (1,1-dimethylethyl) -4-hydroxy-C7-9 branched and straight chain alkyl Ester is mentioned.

As the triazine-based compound, 2-mono (hydroxyphenyl) -1,3,5-triazine compound, 2,4-bis (hydroxyphenyl) -1,3,5-triazine compound, 2,4, 6-tris (hydroxy phenyl) -1,3,5-triazine compound, specifically, 2,4-diphenyl-6- (2-hydroxy-4-methoxyphenyl) -1 , 3,5-triazine, 2,4-diphenyl-6- (2-hydroxy-4-ethoxyphenyl) -1,3,5-triazine, 2,4-diphenyl- (2-hydrate Hydroxy-4-propoxyphenyl) -1,3,5-triazine, 2,4-diphenyl- (2-hydroxy-4-butoxyphenyl) -1,3,5-triazine, 2,4 -Diphenyl-6- (2-hydroxy-4-butoxyphenyl) -1,3,5-triazine, 2,4-diphenyl-6- (2-hydroxy-4-hexyloxyphenyl)- 1,3,5-triazine, 2,4-diphenyl-6- (2-hydroxy-4-octyloxyphenyl) -1,3,5-triazine, 2,4-diphenyl-6- ( 2-hydroxy-4-dodecyloxyphenyl) -1,3,5-triazine, 2,4-diphenyl-6- (2-hydroxy-4-benzyloxyphenyl) -1,3,5- Triazine, 2,4-diphenyl-6- (2-hydroxy-4-butoxyethoxy) -1,3,5-tria , 2,4-bis (2-hydroxy-4-butoxyphenyl) -6- (2,4-dibutoxyphenyl) -1,3,5-triazine, 2,4,6-tris (2- Hydroxy-4-methoxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-4-ethoxyphenyl) -1,3,5-triazine, 2, 4,6-tris (2-hydroxy-4-propoxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-4-butoxyphenyl) -1,3 , 5-triazine, 2,4,6-tris (2-hydroxy-4-butoxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-4- Hexyloxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-4-octyloxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-4-dodecyloxyphenyl) -1,3,5-triazine, 2,4 6-tris (2-hydroxy-4-benzyloxyphenyl) -1,3,5-triazine , 2,4,6-tris (2-hydroxy-4-ethoxyethoxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-4-butoxy Methoxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-4-propoxyoxyphenyl) -1,3,5-triazine, 2,4,6- Tris 2-hydroxy-4-methoxycarbonyl propyloxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-4-ethoxycarbonylethyloxyphenyl) -1 , 3,5-triazine, 2,4,6-tris (2-hydroxy-4- (1- (2-ethoxyhexyloxy) -1-oxopropan-2-yloxy) phenyl) -1 , 3,5-triazine, 2,4,6-tris (2-hydroxy-3-methyl-4-methoxyphenyl) -1,3,5-triazine, 2,4,6-tris (2 -Hydroxy-3-methyl-4-ethoxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-3-methyl-4-propoxy phenyl) -1, 3,5-triazine, 2,4,6-tris (2-hydroxy-3-methyl-4-butoxyphenyl) -1,3,5-triazine, 2,4,6-tris (2- Hydroxy-3-methyl-4-butoxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-3-methyl-4-hexyloxyphenyl) -1,3 , 5-triazine, 2,4,6-tris (2-hydroxy-3-methyl-4-octyloxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy Oxy-3-methyl-4-dodecyloxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-3-methyl-4-benzyloxy Nil) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-3-methyl-4-ethoxyethoxyphenyl) -1,3,5-triazine, 2,4 , 6-tris (2-hydroxy-3-methyl-4-butoxyethoxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-3-methyl-4 Propoxyoxyphenyl) -1,3,5-triazine, 2,4,6-tris (2-hydroxy-3-methyl-4-methoxycarbonyl propyloxyphenyl) -1,3,5 -Triazine, 2,4,6-tris (2-hydroxy-3-methyl-4-ethoxycarbonyl ethyloxyphenyl) -1,3,5-triazine, 2,4,6-tris (2 -Hydroxy-3-methyl-4- (1- (2-ethoxyhexyloxy) -1-oxo propan-2-yloxy) phenyl) -1,3,5-triazine and the like.

Among them, 2,4-bis (2,4-dimethylphenyl) -6- [2-hydroxy-4- (3- in terms of high compatibility with amorphous thermoplastic resins, especially acrylic resins and excellent absorption characteristics. Ultraviolet absorbers having alkyloxy-2-hydroxypropyloxy) -5-α-cumylphenyl] -s-triazine skeleton (alkyloxy; long-chain alkyl oxy groups such as octyloxy, nonyloxy, decyloxy) Can be.

In addition, a ultraviolet absorber having a 2,4,6-tris (hydroxyphenyl) -1,3,5-triazine skeleton is preferably used, and a 2,4,6-tris (2-hydroxy-4-long chain Alkyloxy group substituted phenyl) -1,3,5-triazine skeleton or 2,4,6-tris (2-hydroxy-3-alkyl-4-long chain alkyloxy group substituted phenyl) -1,3,5- Ultraviolet absorbers having a triazine skeleton are particularly preferred triazine ultraviolet absorbers.

As a commercial item, for example, "Chinvin 1577" "Cinubin 460" "Cinubin 477" (made by BASF Japan) as a triazine-type ultraviolet absorber, "Adecastabu LA-31" (made by ADEKA) as a triazole type ultraviolet absorber, etc. Can be mentioned.

These may be used alone or in combination of two or more. Moreover, it is also preferable to use together the method of copolymerizing the said ultraviolet absorbent monomer with a ultraviolet absorber.

Although the compounding quantity of an ultraviolet-stable monomer ultraviolet absorber is not specifically limited, It is preferable that it is 0.01-25 weight% in the film containing an acrylic resin, More preferably, it is 0.05-10 weight%. If the amount is too small, the contribution of improving weather resistance is low, and if too large, the mechanical strength and yellowing may occur.

The light transmittance at a wavelength of 380 nm of the acrylic resin film containing the ultraviolet absorber is preferably 30% or less, more preferably 20% or less, even more preferably 10% or less, and particularly preferably 5% or less.

When the light transmittance at the wavelength of 380 nm exceeds 30%, deterioration of the polarizer cannot be sufficiently suppressed. More preferably, the said light transmittance is 20% or less, More preferably, it is 10% or less, Most preferably, it is 5% or less.

It is preferable that b value of the optical film of this invention is 2.0% or less. More preferably, b value is 1.5% or less, More preferably, it is 1.0% or less, Most preferably, it is 0.5% or less. By setting the b value to 2.0% or less, the color sensation shown when the present optical film is incorporated in the image display device is excellent.

It is preferable that the said ultraviolet absorber is 600 or more in molecular weight, More preferably, it is 650 or more, More preferably, it is 700 or more.

When the said molecular weight is less than 600, foaming may arise at the time of shape | molding the acrylic resin composition which added the ultraviolet absorber, or a ultraviolet absorber may bleed out. In addition, the ultraviolet absorber may evaporate due to the heat applied during molding, resulting in a decrease in the ultraviolet absorbing function of the obtained resin molded article, or the evaporating ultraviolet absorber may contaminate the molding apparatus.

On the other hand, the upper limit of the molecular weight of the ultraviolet absorber is preferably 10000 or less, more preferably 8000 or less, even more preferably 5000 or less. When the said molecular weight exceeds 10000, compatibility with acrylic resin falls, and optical characteristics, such as the color and turbidity, of the finally obtained resin molded article fall.

The acrylic resin film may contain other additives. Other additives include, for example, antioxidants such as hindered phenol-based, phosphorus-based and sulfur-based; Stabilizers such as light resistance stabilizers, weather resistance stabilizers and heat stabilizers; Reinforcing materials such as glass fibers and carbon fibers; Near infrared absorbers; Flame retardants such as tris (dibromopropyl) phosphate, triaryl phosphate and antimony oxide; Antistatic agents composed of anionic, cationic and nonionic surfactants; Coloring agents such as inorganic pigments, organic pigments, and dyes; Organic fillers, inorganic fillers; Anti blocking agents; Resin modifiers; Organic fillers, inorganic fillers; Plasticizers; Lubricant; It is a phase difference reducing agent.

The content of the other additives in the acrylic resin film is preferably 0 to 5% by weight, more preferably 0 to 2% by weight, still more preferably 0 to 1% by weight.

The glass transition temperature (Tg) of the acrylic resin film is preferably 100 ° C. or higher, more preferably 110 ° C. or higher, even more preferably 115 ° C. or higher, particularly preferably 120 ° C. or higher. Although the upper limit of Tg of an acrylic resin film is not specifically limited, From a stretchability of the said film, Preferably it is 170 degrees C or less.

The (meth) acrylic polymer having a ring structure in the main chain increases the Tg of the acrylic resin film and the optical film composed of the film to improve heat resistance.

The thickness of an acrylic resin film is not specifically limited, Preferably it is 5-200 micrometers, More preferably, it is 10-100 micrometers.

When the thickness is less than 5 μm, sufficient strength as the optical film may not be maintained. If the thickness exceeds 200 μm, the transparency of the film is lowered, which may make it unsuitable for use as an optical film.

In addition, the excessively large thickness of the acrylic resin film inhibits the drying of the adhesive composition used for the adhesive layer when bonding the optical film of the present invention with another member (for example, a functional film). In particular, in the case of using the water-based adhesive composition, it is easy to cause a decrease in the quality and productivity of the optical member having a laminated structure between the optical film of the present invention and another member by slowing the drying of water, which is a solvent or a dispersion medium.

The wet tension of the surface of the acrylic resin film is preferably 40 mN / m or more, more preferably 50 mN / m or more, still more preferably 55 mN / m or more. When the wet tension of the surface is 40 mN / m or more, the adhesion between the optical film of the present invention and another member is further improved.

In order to adjust the surface wet tension, any appropriate surface treatment can be performed on the surface of the acrylic resin film. Surface treatment is corona discharge treatment, plasma treatment, ozone spray, ultraviolet irradiation, flame treatment, chemical treatment, for example. Among them, corona discharge treatment and plasma treatment are preferred.

The acrylic resin film may be an unstretched film or a stretched film. The stretched film may be a uniaxial stretched film or a biaxially stretched film. The biaxially oriented film may be any one of a biaxially oriented film and a continuous biaxially oriented film. In addition, the direction of the retardation axis of a stretched film may be a flow direction of a film, may be a width direction, and may be arbitrary directions further.

When the acrylic resin film is a biaxially stretched film, the mechanical strength of the optical film of the present invention is improved. Depending on the composition of an acrylic resin, expression of phase difference by extending | stretching is suppressed and an optically isotropic optical film can be obtained. When the optical film of the present invention is a retardation film, the acrylic resin film is a stretched film.

An acrylic resin film can be formed by a well-known film film-forming method. Film film-forming techniques are the solution casting method (solution flow lead method), the melt extrusion method, the calender method, and the compression molding method, for example. Among them, the solution cast method and the melt extrusion method are preferable.

The acrylic resin used for film-forming of a film can be formed by a well-known method. For example, an acrylic resin is formed by fully mixing the (meth) acrylic polymer, other thermoplastic polymer, additives, etc. which were mix | blended according to the composition of the obtained acrylic resin by an appropriate mixing method.

The mixing method is, for example, extrusion kneading or mixing in solution. Commercial acrylic resin can be used for film-forming. Commercially available acrylic resins are, for example, acrylic pad VH and acrylic pad VRL20A (both manufactured by Mitsubishi Rayon). Any suitable mixer may be used for the extrusion kneading, for example, an omni mixer, single screw extruder, twin screw extruder, pressurized kneader.

The apparatus for implementing the solution cast method is, for example, a drum type casting machine, a band type casting machine, and a spin coater.

The solvent used for the solution cast method is not limited as long as it melt | dissolves an acrylic resin. The solvent is, for example, aromatic hydrocarbons such as benzene, toluene and xylene; Aliphatic hydrocarbons such as cyclohexane and decalin; Esters such as ethyl acetate and butyl acetate; Ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone; Alcohols such as methanol, ethanol, isopropanol, butanol, isobutanol, methyl cellosolve, ethyl cellosolve and butyl cellosolve; Ethers such as tetrahydrofuran and dioxane; Halogenated hydrocarbons such as dichloromethane, chloroform and carbon tetrachloride; Dimethyl formamide; Dimethyl sulfoxide. Two or more types can use a solvent together.

The melt extrusion method is, for example, the T die method or the inflation method. The molding temperature at the time of melt extrusion is preferably 150 to 350 ° C, more preferably 200 to 300 ° C. When the T-die method is selected, for example, a band-shaped acrylic resin film can be formed by providing a T-die at the tip of a known extruder. The formed strip | belt-shaped acrylic resin film is wound up to a roll, and can also be used for a film roll. In the melt-extrusion method, it can carry out continuously from formation of the acrylic resin by mixing of materials, and shaping | molding of the acrylic resin film using the said resin. A band-like optical film can be obtained by easily forming an adhesive layer on a strip | belt-shaped acrylic resin film.

The acrylic resin film which is a stretched film can be formed by extending | stretching the acrylic resin film obtained as mentioned above. The stretching method is not particularly limited, and a known stretching machine can be used for stretching. When forming an acrylic resin film by the T-die method, the uniaxial stretching and the winding of a film can be performed simultaneously by adjusting the temperature of the roll which winds up the formed film.

When forming an acrylic resin film by melt extrusion, the process from formation of the acrylic resin by mixing of materials, to formation of the acrylic resin film, and to obtaining the optical film which is a stretched film can be performed continuously.

After stretching, heat treatment (annealing) on the film can be carried out to stabilize the optical isotropic and mechanical properties of the film. The method and conditions of the heat treatment can be appropriately selected.

(1-2. Easy Adhesive Layer)

The optical film of the present invention has an easy adhesive layer (a) containing a polyester-acrylic composite resin (B).

Although the thickness of an easily bonding layer (a) is not specifically limited, Although it changes with the thickness of an acrylic resin film, 1 nm-10 micrometers are preferable, 10 nm-5 micrometers are more preferable, 50 nm-1.5 micrometers are still more preferable. In this range, according to the easily bonding layer (a), the effect of improving the adhesion between the optical film and the functional coating layer is good. In addition to this, it is possible to suppress the occurrence of retardation on the easily adhesive layer itself.

The easy adhesion layer (a) may contain microparticles | fine-particles within the range which does not impair the said adhesiveness. Any suitable fine particles may be used as the fine particles, and are preferably water dispersible fine particles. Specifically, any of inorganic fine particles and organic fine particles may be used, and organic inorganic composite fine particles may be used.

Examples of the inorganic fine particles include inorganic oxides such as silica, titania, alumina and zirconia, calcium carbonate, talc, clay, calcined kaolin, calcined calcium silicate, hydrated calcium silicate, aluminum silicate, magnesium silicate and calcium phosphate. have.

As organic type microparticles | fine-particles, silicone type resin, a fluorine type resin, (meth) acrylic resin, etc. are mentioned, for example.

Among these, silica is preferable. This is because the effect on the optical properties of the polarizing plate is smaller because the blocking inhibiting ability is further excellent, the transparency is excellent, no haze is generated, and there is no coloring. In addition, since silica has good dispersibility and dispersion stability in the easy adhesive composition, the workability at the time of forming the easy adhesive layer can be further improved. Silica is also excellent in adhesiveness with an acrylic resin film.

The particle diameter (average primary particle diameter) of the fine particles is 300 nm or less, preferably 10 to 300 nm, more preferably 20 to 200 nm, even more preferably 30 to 150 nm.

By using the fine particles having such fine particle diameters, irregularities are appropriately formed on the surface of the easy adhesive layer, so that the frictional force of the contact surface between the acrylic resin film and the easy adhesive layer and / or the easy adhesive layers can be effectively reduced. As a result, the blocking inhibiting ability can be further excellent. In addition, since the average primary particle diameter is smaller than the visible light wavelength and smaller, the light scattering caused by the particles can be suppressed, so that the influence on the optical properties of the polarizing plate can be further suppressed.

The particle size distribution of the fine particles is preferably 1.0 to 1.4, more preferably 1.0 to 1.2.

The average primary particle diameter and particle size distribution of the fine particles can be obtained by a laser diffraction scattering particle size distribution measuring device (eg, Particle Sizing Systems, Submicron Particle Sizer NICOMP380).

Specifically, the equivalent spherical distribution of the fine particles dispersed in the medium is determined by the measuring device. Next, the particle diameter of the particle | grains of 50% of the integrated volume fraction integrated on the large particle side in the calculated | required distribution is calculated | required, and this is set as the average primary particle diameter (d50) of microparticles | fine-particles.

Apart from this, the particle diameter (d25) of the integrated volume fraction 25% and the particle diameter (d75) of the 75% particle are accumulated, and the ratio (d25 / d75) is calculated as the particle size distribution of the fine particles. Shall be. In addition, the medium may be appropriately selected depending on the configuration and capacity of the particle size distribution device, for example water, but is not limited to liquid.

When the composition for forming the easily adhesive layer (a) is water-based, the fine particles are preferably blended as a water dispersion medium. Specifically, when silica is used as the fine particles, it is preferably blended as colloidal silica. As colloidal silica, a commercial item can be used as it is.

As a commercial item, the Kuotoron PL series of the Fuso Chemical Industries, Snowtex series of Nissan Chemical Industries, Ltd. AERODISP series and AEROSIL series of Nippon Aerodrome, etc. are mentioned, for example.

The upper limit of the content rate of the particles in the easy adhesive layer (a) is preferably less than 10% by weight, more preferably less than 5% by weight, even more preferably less than 2% by weight. When the content rate of the fine particles exceeds 10% by weight, the coating film strength of the easy adhesive layer may be lowered or transparency may be inhibited. 0.1 weight% or more is preferable, as for the minimum of the content rate of microparticles | fine-particles in an easily bonding layer, 0.15 weight% or more is more preferable, 0.2 weight% or more is still more preferable. When content of microparticles | fine-particles becomes less than 0.1 weight%, the blocking resistance of an optical film may fall.

The polyester-acrylic composite resin (B) forming the easily adhesive layer (a) may be formed from a mixture of a polyester resin and an acrylic resin, or may be formed from a resin obtained by copolymerizing a (meth) acryl monomer to a polyester resin. . From the viewpoint of environmental regulation, since the aqueous system is more advantageous than the solvent system when forming the easy adhesive layer, the polyester-acrylic composite resin (B) is preferably water dispersible, and more preferably, the polyester resin is water dispersible.

The dicarboxylic acid component that is a copolymerization component of the polyester resin forming the polyester-acrylic composite resin (B) contains an ester-forming sulfonic acid alkali metal salt compound as an essential component and may be contained in addition to the ester-forming sulfonic acid alkali metal salt compound. Examples of the dicarboxylic acid component include aromatic dicarboxylic acids such as phthalic acid, terephthalic acid, dimethyl terephthalic acid, isophthalic acid, dimethyl isophthalic acid, 2,5-dimethyl terephthalic acid, 2,6-naphthalene dicarboxylic acid, biphenyl dicarboxylic acid and orthophthalic acid. Aliphatic dicarboxylic acids such as carboxylic acid, succinic acid, adipic acid, azelaic acid, sebacic acid and dodicarboxylic acid, and alicyclic dicarboxylic acids such as cyclohexane dicarboxylic acid.

As dicarboxylic acid components other than the ester-forming sulfonic acid alkali metal salt compound, aromatic dicarboxylic acid is preferable, and since the aromatic nucleus of the aromatic dicarboxylic acid has high affinity with hydrophobic plastics, the adhesiveness is improved and the hydrolysis resistance is excellent. There is this. In particular, terephthalic acid and isophthalic acid are preferable.

It is preferable to contain 6-20 mol% of ester-forming sulfonic-acid alkali metal salt compounds in (in the said dicarboxylic acid component) among all the acid components. More preferably, it is 10-18 mol%. When the content of the ester-forming sulfonic acid alkali metal salt compound is less than 6 mol%, the dispersion time of the resin with respect to water becomes long, and it cannot be said that solvent resistance is also sufficient. On the contrary, when it exceeds 20 mol%, there exists a tendency for water resistance to fall.

It is preferable that 80-94 mol% of dicarboxylic acid components other than an ester forming sulfonic-acid alkali metal salt compound are contained in all the acid components.

Examples of the ester-forming sulfonic acid alkali metal salt compound include alkali metal salts such as sulfoterephthalic acid, 5-sulfoisophthalic acid, 4-sulfoisophthalic acid and 4-sulfonaphthalic acid-2,7-dicarboxylic acid (alkali metal salts of sulfonic acid). ) And these ester-forming derivatives, and sodium salt of 5-sulfoisophthalic acid and ester-forming derivatives thereof are more preferably used.

As a diglycol component which is a copolymerization component of a polyester resin, diethylene glycol, C2-C8 aliphatic, or C6-C12 alicyclic glycol etc. are mentioned. Specific examples of aliphatic glycols having 2 to 8 carbon atoms or alicyclic glycols having 6 to 12 carbon atoms include ethylene glycol, 1,3-propanediol, 1,2-propylene glycol, neopentyl glycol, 1,4-butanediol, and 1,4- Cyclohexane dimethanol, 1,3-cyclohexane dimethanol, 1,2-cyclohexane dimethanol, 1,6-hexanediol, p-xylene glycol, triethylene glycol, and the like. More than one species can be used together.

It is preferable that the usage-amount of the said dicarboxylic acid component and the usage-amount of a diglycolic component are 2: 1-1: 3 by molar ratio.

It is preferable to contain 20-80 mol% of diethylene glycol in the total glycol component. Although diethylene glycol can obtain solvent resistance to alcohol outside this range, solvent resistance may be insufficient for aromatic solvents such as toluene and xylene.

The polyester resin needs to have a number average molecular weight of 2,000-30,000, and a preferable number average molecular weight is 2,500-25,000. When the number average molecular weight is less than 2,000, resin physical properties such as water resistance and solvent resistance may be lowered. When the number average molecular weight is more than 30,000, only a resin that is difficult to handle due to difficult water dispersibility may be obtained.

Although polyester resin is manufactured by esterification or transesterification of dicarboxylic acid and diglycol by a well-known manufacturing technique, it is manufactured by polycondensation reaction, However, The manufacturing method is not restrict | limited at all. That is, the target polyester resin can be obtained by esterification or transesterification of the above-mentioned acid component and glycol component at 130-200 degreeC, and then condensation reaction at 200-250 degreeC under reduced pressure conditions.

Reaction catalysts used at this time include metal acetates such as zinc acetate and manganese acetate, metal oxides such as antimony oxide and germanium oxide, and titanium compounds.

When making a polyester resin water dispersible, it is used, disperse | distributing water uniformly to water containing water or an aqueous solvent under 50-90 degreeC warm stirring. Since the water dispersion obtained in this way is difficult to obtain a uniform dispersion when the solid content concentration is high, the polyester solid content concentration is preferably 30% by weight or less.

Specific examples of the aqueous solvent include lower alcohols such as methanol, ethanol, normal propanol and isopropanol, polyhydric alcohols such as ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, glycerin, ethylene glycol monomethyl ether, ethylene glycol monoethyl Ether, propylene glycol monomethyl ether, propylene glycol mono ethyl ether, propylene glycol acetate, diethylene glycol monomethyl ether, dipropylene glycol monomethyl ether and the like.

It is preferable that the acrylic resin composited with polyester resin has an epoxy group. When polyester-acrylic composite resin (B) has an epoxy group, the solvent resistance of the easily bonding layer (a) and adhesiveness with a functional coating layer improve.

The epoxy group-containing acrylic resin is a resin obtained by copolymerizing a homopolymer of an epoxy group-containing radical polymerizable unsaturated monomer or an epoxy group-containing radical polymerizable unsaturated monomer with another radical polymerizable unsaturated monomer copolymerizable thereto.

It is preferable to contain 10-100 weight% in epoxy monomer containing radically polymerizable unsaturated monomers, More preferably, it is 20-100 weight%.

It is thought that an epoxy group containing radically polymerizable unsaturated monomer improves water resistance and solvent resistance by advancing internal crosslinking of an epoxy group containing acrylic resin. In particular, solvent resistance to ketone solvents such as acetone and methyl ethyl ketone and ester solvents such as ethyl acetate and butyl acetate is remarkable.

Solvent resistance to alcohol is obtained even if the content of the epoxy group-containing radically polymerizable unsaturated monomer is less than 10% by weight, but solvent resistance to ketone solvents such as acetone and methyl ethyl ketone, and ester solvents such as ethyl acetate and butyl acetate is obtained. Insufficient

Examples of the epoxy group-containing radically polymerizable unsaturated monomers include glycidyl ethers such as glycidyl acrylate, glycidyl methacrylate and allylglycidyl ether.

Examples of the radical polymerizable unsaturated monomer copolymerizable with the epoxy group-containing radical polymerizable unsaturated monomer include vinyl esters, unsaturated carboxylic acid esters, unsaturated carboxylic acid amides, unsaturated nitriles, unsaturated carboxylic acids, allyl compounds, nitrogen-containing vinyl monomers, And hydrocarbon vinyl monomers or vinylsilane compounds.

Examples of vinyl esters include vinyl propionate, vinyl stearate, higher tertiary vinyl esters, vinyl chloride, and vinyl bromide.

Unsaturated carboxylic acid esters include methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethyl hexyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, butyl maleate, octyl maleate, butyl fumarate, octyl fumarate, Methacrylic acid hydroxyethyl, acrylic acid hydroxyethyl, methacrylic acid hydroxypropyl, hydroxypropyl acrylate, dimethyl aminoethyl methacrylate, dimethylaminoethyl acrylate, ethylene glycol dimethacrylic acid ester, ethylene glycol diacrylic acid ester, Polyethylene glycol dimethacrylic acid ester and polyethylene glycol diacrylic acid ester are mentioned.

Examples of the unsaturated carboxylic acid amide include acrylamide, methacrylamide, methylol acrylamide, and butoxymethylol acrylamide. Acrylonitrile is mentioned as unsaturated nitrile.

Examples of the unsaturated carboxylic acid include acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, maleic acid acid ester, fumaric acid acid ester, and itaconic acid acid ester.

Examples of the allyl compound include allyl acetate, allyl methacrylate, allyl acrylate, and diallyl itaconic acid.

In addition, vinyl pyridine and vinyl imidazole are mentioned as a nitrogen-containing vinyl monomer, and ethylene, propylene, hexene, octene, styrene, vinyl toluene, and butane diene are mentioned as a hydrocarbon vinyl monomer.

Examples of the vinylsilane compound include dimethyl vinyl methoxysilane, dimethyl vinylethoxy silane, methylvinyl dimethoxy silane, methylvinyl diethoxy silane, γ-methacryloxy propyl trimethoxy silane and γ-methacryloxy propyl dimethoxy silane. Can be.

It is preferable that polyester-acrylic composite resin (B) further has a carboxyl group. When a radically polymerizable unsaturated monomer is used, when unsaturated carboxylic acids, such as acrylic acid and methacrylic acid, are used, the effect of improving solvent resistance and adhesiveness with a functional coating layer will be exhibited further by crosslinking with an epoxy group.

It is preferable to contain 5-20 weight% of unsaturated carboxylic monomers in all monomers. If the content of the unsaturated carboxylic acid monomer is less than 5% by weight, no combined effect is observed. If the content of the unsaturated carboxylic acid monomer is more than 20% by weight, the viscosity during polymerization is too high, the liquid gels over time, and the storage stability may be deteriorated.

Although epoxy group containing acrylic resin is manufactured by a well-known manufacturing technique, it does not restrict | limit any about the manufacturing method. Here, the manufacturing method by emulsion polymerization is described.

For example, ion-exchanged water, a polymerization initiator, and a surfactant are put in a reaction chamber, ion-exchanged water and a surfactant are put into a dropping chamber, a monomer is added to prepare an emulsion, and a reaction is performed by dropping an emulsion. . The reaction temperature is 60 ~ 100 ℃, the reaction is carried out for 4 hours to 10 hours.

As surfactant used for emulsion polymerization, 1 type (s) or 2 or more types can be used together with general anionic or nonionic reactive surfactant and non-reactive surfactant.

Specific examples of the reactive surfactant include anionic surfactants such as alkylallylsulfo succinic acid, polyoxy ethylene alkyl propenyl phenyl ether sulfate ester salts, polyoxy alkylene alkenyl ether sulfate, and (meth) acrylate sulfate ester salts, and polyoxy. And nonionic surfactants such as ethylene alkyl propenyl phenyl ether, polyoxy alkylene alkenyl ether, and (meth) acrylate sulfate esters.

Specific examples of the non-reactive surfactants include anionic surfactants such as alkyl sulfate esters, alkyl benzene sulfonic acid salts, alkyl sulfo succinate salts, alkyldiphenyl ether disulfonates, polyoxy ethylene alkyl sulfates and polyoxy ethylene alkyl phosphate esters; And nonionic surfactants such as polyoxy ethylene alkyl ether, polyoxy ethylene alkyl phenyl ether, polyoxy ethylene diphenyl ether, and polyoxy ethylene fatty acid ester.

As a polymerization initiator used for emulsion polymerization, general radically polymerizable initiators, for example, water-soluble peroxides such as potassium persulfate, ammonium persulfate, hydrogen peroxide, or oil-soluble peroxides such as benzoyl peroxide or t-butyl hydroperoxide, or azobis iso Azo compounds, such as butyronitrile, etc. can be mentioned.

The polyester-acrylic composite resin (B) of the present invention preferably has a resin solid content weight ratio of 10 to 80/90 to 20, more preferably 20 to 70/80 to 30, of the polyester resin component and the acrylic resin component. .

If the polyester resin is less than 10% by weight, that is, the acrylic resin is more than 90% by weight, the adhesion to the substrate and the transparency of the coating are lowered. If the polyester resin is more than 80% by weight, the acrylic resin is less than 20% by weight. Sufficient solvent resistance and water resistance cannot be obtained.

The easy adhesive layer (a) may be formed on one main surface of the acrylic resin film. In addition, in this specification, the "main surface" means the surface which is determined by the side of the film in the longitudinal direction and the width direction of a film, ie, the surface and the back surface, not the surface in the thickness direction of a film.

The formation method of the easily adhesive layer with respect to the main surface of an acrylic resin film is not restrict | limited, It can carry out according to a well-known method. The easy adhesive layer is preferably formed by applying the easy adhesive composition containing the polyester-acrylic composite resin (B) to the main surface of the acrylic resin film to form a coating film of the composition, followed by drying the formed coating film. The easy adhesive composition may contain the above fine particles.

The easy adhesive composition is preferably an aqueous composition. Compared with the organic solvent composition, the aqueous composition has less environmental load generated when an easy adhesive layer is formed, and is excellent in workability. An aqueous composition is a dispersion of resin which has easy adhesiveness, for example. Dispersions are typically emulsions of resins with easy adhesion. The emulsion of the polyester-acrylic composite resin becomes a layer containing the polyester-acrylic composite resin (B) by drying. The fine particles contained in the emulsion remain in the resin layer as it is.

When the easily adhesive composition containing the polyester-acrylic composite resin (B) is water-based, it is preferable to use an organic solvent compatible with water. The organic solvent may be, for example, an ester solvent such as ethyl acetate, butyl acetate or ethyl cellosolve acetate; Ketone solvents such as acetone, methyl ethyl ketone and methyl isobutyl ketone; Ether solvents such as dioxane, tetrahydrofuran and propylene glycol monomethyl ether.

The easy adhesion composition may include additives in addition to the resin and the fine particles having easy adhesion. The additives are, for example, dispersion stabilizers, thixotropy agents, antioxidants, ultraviolet absorbers, antifoaming agents, thickeners, dispersants, surfactants, catalysts and antistatic agents.

In the water-based easy adhesive composition used for forming the easy adhesive layer (a) which is a polyester-acrylic composite resin layer, the content of the polyester-acrylic composite resin (B) in the composition is preferably 1 to 20% by weight, , 2 to 15% by weight is more preferable. When the content rate is in these ranges, the coating property at the time of apply | coating an easy adhesive composition to the surface of an acrylic resin film is not only high, but the effect of an easy adhesive layer can fully be ensured.

When such a composition contains a crosslinking agent further, 1-30 weight part is preferable with respect to 100 weight part of polyester-acrylic composite resins (B), and, as for content of a crosslinking agent, 3-20 weight part is more preferable. 0.3-10 weight part is preferable with respect to 100 weight part of polyester-acrylic composite resins (B), and, as for the content rate of the microparticles | fine-particles in the easily adhesive composition containing a polyester-acrylic composite resin, 0.5-1 weight part is more preferable.

In the optical film of the present invention, the easy adhesive layer (b) may be formed on the main surface of the acrylic resin film on the side opposite to the main surface on which the easy adhesive layer (a) is formed. Resin which comprises an easily bonding layer (b) is not specifically limited, Well-known resin which has easy adhesiveness may be sufficient, For example, urethane resin, a cellulose resin, a polyol resin, a polycarboxylic acid resin, a polyester resin, an acryl Resin.

The number average molecular weight of the resin constituting the easy adhesive layer (b) is preferably 0.50,000 to 600,000, more preferably 10,000 to 400,000.

The easy adhesive layer (b) may contain fine particles similarly to the easy adhesive layer (a), and the above fine particles can be enumerated as preferable fine particles.

As for resin which comprises the easily bonding layer (b), urethane resin is preferable. In this case, the adhesiveness to the polarizer is improved than when the easy adhesive layer is another resin layer.

The urethane resin is not particularly limited and is typically a resin obtained by reacting a polyol and a polyisocyanate. The polyol can employ any polyol having two or more hydroxyl groups in the molecule. Polyols are, for example, polyacrylic polyols, polyester polyols, polyether polyols. Two or more polyols can be combined.

Polyacrylic polyols are typically copolymers of (meth) acrylic acid ester monomers with monomers having hydroxyl groups.

The (meth) acrylic acid ester monomer is methyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and cyclohexyl (meth) acrylate, for example.

The monomer having a hydroxyl group may be, for example, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, ( (Meth) acrylic acid hydroxyalkyl esters such as 4-hydroxybutyl methacrylate and 2-hydroxypentyl (meth) acrylate; (Meth) acrylic acid monoesters of polyhydric alcohols such as glycerin and trimethylol propane; N-methylol (meth) acrylamide.

The polyacryl polyol may further be a copolymer with another monomer. The other monomer is not limited as long as possible copolymerization with the (meth) acrylic acid ester monomer and the monomer having a hydroxyl group.

The other monomers include, for example, unsaturated monocarboxylic acids such as (meth) acrylic acid; Unsaturated dicarboxylic acids such as maleic acid and anhydrides thereof, and mono or diesters; Unsaturated nitriles such as (meth) acrylonitrile; Unsaturated amides such as (meth) acrylamide and N-methylol (meth) acrylamide; Vinyl esters such as vinyl acetate and vinyl propionate; Vinyl ethers such as methyl vinyl ether; Α-olefins such as ethylene and propylene; Halogenated α, β-unsaturated aliphatic monomers such as vinyl chloride and vinylidene chloride; Α, β-unsaturated aromatic monomers such as styrene and α-methylstyrene.

Polyester polyols are typically obtainable by reaction of a polybasic acid component with a polyol component. The polybasic acid component is for example orthophthalic acid, isophthalic acid, terephthalic acid, 1,4-naphthalene dicarboxylic acid, 2,5-naphthalene dicarboxylic acid, 2,6-naphthalene dicarboxylic acid, biphenyl dicarboxylic acid Aromatic dicarboxylic acids such as tetrahydro phthalic acid; Oxalic acid, succinic acid, malonic acid, glutaric acid, adipic acid, pimeric acid, sublinic acid, azelaic acid, sebacic acid, decane dicarboxylic acid, dodecane dicarboxylic acid, octadecane dicarboxylic acid, tartaric acid Aliphatic dicarboxylic acids such as alkyl succinic acid, linoleic acid, maleic acid, fumaric acid, mesaconic acid, citraconic acid and itaconic acid; Alicyclic dicarboxylic acids such as hexahydro phthalic acid, tetrahydro phthalic acid, 1,3-cyclohexane dicarboxylic acid and 1,4-cyclohexane dicarboxylic acid; Or reactive derivatives such as acid anhydrides, alkyl esters, and acid halides thereof.

The polyol component is, for example, ethylene glycol, 1,2-propane diol, 1,3-propane diol, 1,3-butanediol, 1,4-butanediol, neopentyl glycol, pentanediol, 1,6-hexanediol , 1,8-octanediol, 1,10-decanediol, 1-methyl-1,3-butylene glycol, 2-methyl-1,3-butylene glycol, 1-methyl-1,4-pentylene glycol , 2-methyl-1,4-pentylene glycol, 1,2-dimethyl-neopentyl glycol, 2,3-dimethyl-neopentyl glycol, 1-methyl-1,5-pentylene glycol, 2-methyl-1 , 5-pentylene glycol, 3-methyl-1,5-pentylene glycol, 1,2-dimethylbutylene glycol, 1,3-dimethyl butylene glycol, 2,3-dimethyl butylene glycol, 1,4- Dimethyl butylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, dipropylene glycol, polypropylene glycol, 1,4-cyclohexane dimethanol, 1,4-cyclohexane diol, bisphenol A, bisphenol F, hydrogenated bisphenol A, hydrogenated bisphenol F.

Polyether polyols are typically obtained by ring-opening polymerization of alkylene oxides to polyhydric alcohols. Polyhydric alcohols are, for example, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, glycerin, trimethylol propane. Alkylene oxide is, for example, ethylene oxide, propylene oxide, butylene oxide, styrene oxide, tetrahydrofuran.

The polyisocyanate is, for example, tetramethylene diisocyanate, dodecamethylene diisocyanate, 1,4-butane diisocyanate, hexamethylene diisocyanate, 2,2,4-trimethyl hexamethylene diisocyanate, 2,4,4-trimethyl Aliphatic diisocyanates such as hexamethylene diisocyanate, lysine diisocyanate, 2-methyl pentane-1,5-diisocyanate, and 3-methylpentane-1,5-diisocyanate; Isophorone diisocyanate, hydrogenated xylene diisocyanate, 4,4'-cyclohexyl methane diisocyanate, 1,4-cyclohexane diisocyanate, methylcyclohexylene diisocyanate, 1,3-bis (isocyanate methyl) cyclohexane, etc. Alicyclic isocyanate; Toylene diisocyanate, 2,2'-diphenylmethane diisocyanate, 2,4'-diphenyl methane diisocyanate, 4,4'-diphenyl methane diisocyanate, 4,4'-diphenyl dimethyl methane diisocyanate, 4 Aromatic diisocyanates such as, 4'-dibenzyl diisocyanate, 1,5-naphthalene diisocyanate, xylene diisocyanate, 1,3-phenyl diisocyanate, 1,4-phenylene diisocyanate; Aromatic aliphatic diisocyanates such as dialkyl diphenyl methane diisocyanate, tetraalkyl diphenyl methane diisocyanate, and α, α, α, α-tetramethyl xylene diisocyanate.

The urethane resin preferably has a carboxyl group. By having a carboxyl group, the performance (easiness of adhesiveness) of an easily bonding layer improves. This effect is particularly noticeable in an environment of high temperature and high humidity.

The urethane resin which has a carboxyl group can be obtained, for example by making the polyol and polyisocyanate react, as well as the chain extender which has a free carboxyl group. The chain extenders with free carboxyl groups are, for example, dihydroxy carboxylic acid, dihydroxy succinic acid. Dihydroxy carboxylic acid is dialkylol alkanoic acid, such as dimethylol alkanoic acid (for example, dimethylol acetic acid, dimethylol butanoic acid, dimethylol propionic acid, dimethylol butyric acid, dimethylol pentanic acid).

The acid value of the urethane resin is preferably 10 or more, more preferably 10 to 50, particularly preferably 20 to 45. In these cases, the performance (e.g., adhesion with other functional films such as polarizers) of the easy adhesive layer is further improved.

In addition to each component mentioned above, a urethane resin may be further obtained by reaction with another polyol or other chain lengthening agent.

Other polyols include, for example, sorbitol, 1,2,3,6-hexane tetraol, 1,4-sorbitan, 1,2,4-butane triol, 1,2,5-pentane triol, glycerin, It is a polyol which has three or more hydroxyl groups, such as trimethylol ethane, a trimethylol propane, penta erythritol.

Other chaining agents are, for example, ethylene glycol, diethylene glycol, triethylene glycol, 1,3-propane diol, 1,3-butanediol, 1,4-butanediol, neopentyl glycol, pentanediol, 1,6-hexane Glycols such as diol and propylene glycol; Aliphatic diamines such as ethylene diamine, propylene diamine, hexamethylene diamine, 1,4-butanediamine and aminoethyl ethanol amine; Alicyclic diamines such as isophorone diamine and 4,4'-dicyclohexyl methane diamine; Aromatic diamines such as xylene diamine and triylene diamine.

The urethane resin can be formed by applying a known method. The method is, for example, a one-shot method in which each component is reacted at once, and a multi-step method in which stepwise reactions are performed. Since the urethane resin which has a carboxyl group is easy to introduce | transduce a carboxyl group, it is preferable to form by the multistep method. The catalyst used for formation of a urethane resin is not specifically limited.

It is preferable that the water-based easy adhesive composition used for formation of the easily adhesive layer (b) which is a urethane resin layer contains a neutralizing agent other than microparticles | fine-particles and a urethane resin. In this case, the stability of the urethane resin in the easily adhesive composition is improved. Neutralizers are, for example, ammonia, N-methyl morpholine, triethyl amine, dimethyl ethanolamine, methyl diethanol amine, triethanol amine, morpholine, tripropyl amine, ethanol amine, triisopropanol amine, 2-amino-2- Methyl-1-propanol.

When the easily adhesive composition containing a urethane resin is water-based, when forming a urethane resin, it is preferable to use the organic solvent which is inert with respect to polyisocyanate and is compatible with water. Organic solvents such as ester solvents such as ethyl acetate, butyl acetate and ethyl cellosolve acetate; Ketone solvents such as acetone, methyl ethyl ketone and methyl isobutyl ketone; Ether solvents such as dioxane, tetrahydrofuran and propylene glycol monomethyl ether.

It is preferable that the easily adhesive composition containing a urethane resin contains a crosslinking agent, and in this case, the performance of an easily adhesive layer improves. The crosslinking agent is not particularly limited. When the urethane resin has a carboxyl group, the crosslinking agent is preferably a polymer having a group capable of reacting with the carboxyl group.

The group which can react with a carboxyl group is an organic amino group, an oxazoline group, an epoxy group, a carbodiimide group, for example, and an oxazoline group is preferable. When the crosslinking agent having an oxazoline group is mixed with the urethane resin, the pot life at room temperature is long, and the workability is good because the crosslinking reaction proceeds by heating. The said polymer is a (meth) acryl polymer and a styrene acrylic polymer, for example, and a (meth) acryl polymer is preferable. When the crosslinking agent is a (meth) acrylic polymer, the performance of the easy adhesive layer is further improved. In addition to this, (meth) acrylic polymers are stably compatible with water-based easy adhesive compositions and crosslink urethane resins well.

In the easily adhesive composition containing the urethane resin, the content of the urethane resin in the composition is preferably 1.5 to 15% by weight, more preferably 2 to 10% by weight. When content rate exists in such a range, coatability at the time of apply | coating an easily adhesive composition to the surface of an acrylic resin film is high. When this composition contains a crosslinking agent further, 1-30 weight part is preferable with respect to 100 weight part of urethane resins (solid content), and, as for content of a crosslinking agent, 3-20 weight part is more preferable. 0.3-10 weight part is preferable with respect to 100 weight part of urethane resins (solid content), and, as for the content rate of the microparticles | fine-particles in the easily adhesive composition containing a urethane resin, 0.5-1 weight part is more preferable.

(1-3.optical film)

The optical film of the present invention is an optical film having an acrylic resin film composed of an acrylic resin (A) and an easy adhesive layer (a) containing a polyester-acrylic composite resin (B).

An example of the optical film of this invention is shown in FIG. The optical film 1a shown in FIG. 1 has a structure in which the easily bonding layer (a) 3 was formed in one surface of the acrylic resin film 2. FIG. The specific structure of the acrylic resin film 2 and the easily bonding layer (a) 3 is as above-mentioned.

The optical film of this invention is a film which has an easily bonding layer (a) which is compatible with blocking resistance and transparency. In terms of transparency, the optical film of the present invention usually has a haze of 1.0% or less. According to the structure of the optical film of this invention, its haze is 0.5% or less, Furthermore, it is 0.3% or less. Haze is measured in accordance with the provisions of JIS K7136.

The optical film of the present invention can improve the adhesive strength with the functional coating layer by having the easy adhesive layer (a), and can also improve the fracture strength of the film. Generally, it is known that the acrylic resin film is improved by stretching the film, but after forming the easy adhesive layer (a) having excellent adhesion with the acrylic resin film, the acrylic resin film is stretched to further improve the fracture resistance. You can.

The optical film of this invention is a polarizer protective film, retardation film, a viewing angle compensation film, a light-diffusion film, a reflective film, an antireflection film, an anti-glare film, a brightness improving film, and a conductive film for touch panels, for example.

The phase difference represented by the optical film of the present invention can be controlled by the composition and the stretched state of the acrylic resin film. The optical film of the present invention may be an optically isotropic film, or may be a film having optical anisotropy (for example, expressing birefringence such as retardation).

The optical film of the present invention may be wound on a roll (may be a film roll). Since the optical film of this invention is excellent in blocking resistance, it is suitable for a film roll.

FIG. 2 shows an embodiment of the optical film according to the present invention, and shows an optical film having a functional coating layer formed on a surface of the easy adhesive layer (a) that faces the surface of the acrylic resin film. That is, the optical film 1b in which the various functional coating layers 4 were formed on the easily bonding layer (a) 3 may be sufficient as the optical film of this invention as shown in FIG.

The functional coating layer may be, for example, an antistatic layer, a hard coat layer, a non-glare layer, an antireflection layer such as a low reflection layer or a moth eye layer, an ultraviolet ray blocking layer, a heat ray blocking layer, an electromagnetic wave blocking layer, a gas barrier layer, It is an antifouling layer, such as a photocatalyst layer, an adhesive agent layer, etc., and can be used suitably for the outermost surface of various image display apparatuses.

In addition, "the surface of the said easily bonding layer (a) which opposes the surface of the said acrylic resin film side" means the surface which faces the surface in close contact with the said acrylic resin film among the surfaces which the easily bonding layer (a) has.

FIG. 3 shows an embodiment of the optical film according to the present invention, wherein an optical film having an adhesive layer formed on a surface of the easy adhesive layer (b) that faces the acrylic resin film side is an adhesive layer. The optical member joined with the other member is shown through. In Fig. 3, 1c is an optical film, 5 is an easy adhesive layer (b), 6 is an adhesive layer, and 7 is another member.

In addition, "the surface of the said easily bonding layer (b) which opposes the surface of the said acrylic resin film side" means the surface which faces the surface in close contact with the said acrylic resin film among the surfaces which the easily bonding layer (b) has.

As shown in FIG. 3, the optical film of the present invention may be bonded to another member 7 such as a functional film to form an optical member. At this time, the surface of the easy adhesion layer (b) 5 side (surface on the opposite side to the surface on which the easy adhesive layer (a) is formed) in the optical film 1c of the present invention is easily provided through the adhesive layer (b) 5 and the adhesive layer 6. It is preferable to join with another member.

As shown in FIG. 3, the optical film of the present invention may be a polarizing plate bonded to the polarizer 7 through an easy adhesive layer (b) and an adhesive layer 6. That is, the other member 7 may be a polarizer.

4 shows an embodiment of the polarizing plate according to the present invention, and shows a polarizing plate obtained by bonding the optical film according to the present invention to a polarizer. In FIG. 4, 1c and 1d are optical films, 5 are easy adhesive layers (b), 6 and 9 are adhesive bonding layers, and 8 are polarizers. The optical films 1c and 1d each have an easy adhesive layer (b) 5, and the adhesive agent layer 6 is formed in the surface of each easy adhesive layer (b) 5 facing the surface of the said acrylic resin film 2 side, The said point The adhesive bond layer 6 is bonding with the surface of the polarizer 8.

The optical film of the present invention is suitable for use in an image display device. The image display device is, for example, an electroluminescence (EL) display panel, a plasma display panel (PDP), a field emission display (FED: Field Emission Display), or an LCD. The LCD has a liquid crystal cell and a polarizing plate disposed on at least one main surface of the liquid crystal cell.

〔2. Polarizer]

The polarizing plate of this invention is demonstrated. The polarizing plate of this invention has the optical film which concerns on this invention. In the LCD, a pair of polarizing plates are arranged to sandwich the liquid crystal cell in accordance with its image display principle. The polarizing plate of the present invention has, for example, a structure in which the optical film (polarizer protective film) of the present invention is laminated on at least one surface of the polarizer via an easy adhesive layer.

Conventionally, a triacetyl cellulose (TAC) film is used for a polarizer protective film. However, the TAC film does not have sufficient heat and moisture resistance, and when the TAC film is used as a polarizer protective film, the characteristics of the polarizing plate may be degraded under high temperature or high humidity environment. In addition, the TAC film has a phase difference in the thickness direction, and the phase difference adversely affects the viewing angle characteristic of an image display device such as an LCD, particularly a large screen image display device.

On the other hand, since the optical film of this invention which is a polarizer protective film consists of an acrylic resin film, compared with a TAC film, it can improve moisture-heat resistance and an optical characteristic.

Polarizing plates are typically produced by laminating an optical film and a polarizer through an adhesive layer (adhesive layer). When the optical film of this invention has an easily bonding layer (b), both are laminated | stacked so that an easily bonding layer (b) may be a polarizer side.

Specifically, for example, after applying the adhesive composition which becomes an adhesive layer (adhesive layer) after drying to either surface chosen from a polarizer or an optical film, both are bonded and dried.

The coating method of the adhesive composition is, for example, a roll method, a spray method, or a dipping method. When the adhesive composition comprises a metal compound colloid, the adhesive composition is applied so that the thickness of the adhesive layer after drying is larger than the average particle diameter of the metal compound colloid particles. The drying temperature is typically 5 to 150 ° C, preferably 30 to 120 ° C. The drying time is typically at least 120 seconds, preferably at least 300 seconds.

The polarizer is not limited, and any appropriate polarizer can be adopted depending on the function required as the polarizing plate. The polarizer is, for example, a hydrophilic polymer film such as a polyvinyl alcohol (PVA) based film, a partially formalized PVA based film, a partial gumification film of ethylene-vinyl acetate copolymer (EVA), or a dichroic dye such as iodine or dichroic dye. A film uniaxially stretched by adsorbing a substance; It is a polyene type orientation film using the dehydration process of PVA or the dehydrochlorination process of polyvinyl chloride. Especially, the film uniaxially stretched by making a dichroic substance adsorb | suck to a PVA system film is preferable as a polarizer. This polarizer shows a high polarization dichroic ratio. The thickness of a polarizer is not limited, Generally, it is about 1-80 micrometers.

The polarizer which uniaxially stretched by adsorbing iodine to a PVA system film can be manufactured by dyeing a PVA system film by immersion in the aqueous solution containing iodine, and uniaxially stretching by 3-7 times the draw ratio.

The aqueous solution used for dyeing may include boric acid, zinc sulfate, zinc chloride and the like as necessary. As an aqueous solution containing iodine, you may use aqueous solution of iodide, such as potassium iodide.

The PVA film can be washed by immersion in water before dyeing. By washing with a PVA-type film, the contamination, an antiblocking agent, etc. which exist in the surface of the said film can be removed. In addition, since the PVA film is expanded by water washing, staining is suppressed during dyeing. Stretching may be performed before dyeing, after dyeing, or simultaneously with dyeing.

The adhesive composition which becomes an adhesive layer (adhesive layer) after drying is not restrict | limited. It is preferable that an adhesive composition contains PVA system resin.

PVA-based resins include, for example, the following polymers: saponified polyvinyl acetate and derivatives thereof; Saponified copolymers of vinyl acetate with other monomers; Modified PVA in which PVA is acetalized, urethaneized, etherified, grafted or phosphoric acid esterified.

The other monomers include, for example, unsaturated carboxylic acids such as maleic acid (anhydride), fumaric acid, crotonic acid, itaconic acid, (meth) acrylic acid and esters thereof; Α-olefins such as ethylene and propylene; (Meth) allyl sulfonic acid (soda), sulfonic acid soda (mono alkyl malate), disulfonic acid soda alkyl ralate, N-methylol acrylamide, acrylamide alkyl sulfonic acid alkali salt, N-vinyl pyrrolidone, N -Vinyl pyrrolidone derivatives. It is preferable that PVA system resin contains acet acetyl group containing PVA. In this case, the adhesiveness of a polarizer and an optical film (acrylic resin film) improves, and the durability of a polarizing plate improves.

The average degree of polymerization of the PVA-based resin is preferably about 100 to 5000, more preferably 1000 to 4000, from the viewpoint of the adhesiveness of the adhesive composition. As for the average gelation degree of PVA system resin, about 85-100 mol% is preferable from a viewpoint of the adhesiveness of an adhesive composition, and 90-100 mol% is more preferable.

Acetic acetyl group containing PVA can be obtained, for example by making PVA and diketone react by arbitrary methods. Specific examples include a method of adding diketene to a dispersion obtained by dispersing PVA in a solvent such as acetic acid; Diketene is added to a solution in which PVA is dissolved in a solvent such as dimethyl formamide or dioxane; It is a method of directly contacting diketene gas or liquid diketene with PVA.

Acetyl acetyl group modification degree in acet acetyl group containing PVA is typically 0.1 mol% or more, preferably 0.1-40 mol%, more preferably 1-20 mol%, still more preferably 2-7 mol% to be. At a degree of denaturation of less than 0.1 mol%, the effect of denaturation (eg, improvement in water resistance) may be insufficient. If the degree of modification exceeds 40 mol%, the water resistance does not improve further. Acetic acetyl group denaturation of PVA can be measured by NMR.

The adhesive composition may comprise a crosslinking agent. The crosslinking agent is not limited, but is a compound having at least two functional groups exhibiting reactivity to the PVA-based resin.

The crosslinking agent may be, for example, an alkylene diamine having an alkylene group and two amino groups, such as ethylene diamine, triethylene diamine, hexa methylene diamine; Toylene diisocyanate, hydrogenated toylene diisocyanate, trimethylol propane triisocyanate aduct, triphenyl methane triisocyanate, methylene bis (4-phenylmethane triisocyanate), isophorone diisocyanate, and ketooxime block water or phenols thereof Isocyanates such as block water; Ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, glycerin diglycidyl ether, glycerin triglycidyl ether, 1,6-hexanediol diglycidyl ether, trimethylol propane triglycidyl ether, di Epoxy, such as glycidyl aniline and diglycidyl amine; Monoaldehydes such as formaldehyde, acetaldehyde, propion aldehyde and butyl aldehyde; Dialdehydes such as glyoxal, malondialdehyde, succinic dialdehyde, glutaric dialdehyde, maleindialdehyde and phthaldialdehyde; Amino-formaldehyde resins such as methylol urea, methylol melamine, alkylated methylol urea, alkylated methylol melamine, acetguanamine, a condensate of benzoguanamine and formaldehyde; Monovalent to trivalent metal salts and oxides such as sodium, potassium, magnesium, calcium, aluminum, iron and nickel.

Especially, a crosslinking agent is amino-formaldehyde resin and dialdehyde. The amino-formaldehyde resin preferably has a methylol group, with methylolmelamine being suitable. Dialdehyde is suitable glyoxal.

The compounding quantity of the crosslinking agent in an adhesive composition can be set suitably according to the kind of PVA-type resin. Generally, it is about 10-60 weight part with respect to 100 weight part of PVA system resin, and 20-50 weight part is preferable. Good adhesiveness is obtained in this range. When the compounding quantity of a crosslinking agent becomes too large, since the reaction through a crosslinking agent advances rapidly, there exists a tendency for an adhesive composition to gelatinize. For this reason, the working time (pot life) as an adhesive composition becomes extremely short, and industrial use may become difficult.

The adhesive composition may comprise a metal compound colloid. The metal compound colloid may be a colloid in which particles of the metal compound are dispersed in a dispersion medium. The metal compound colloid may be a colloid having permanent stability by electrostatic stabilization due to the mutual repulsion of the same kind of charge of the particles. When the adhesive composition contains a colloidal metal compound, even if the compounding amount of the crosslinking agent is large, for example, the stability of the adhesive composition is improved.

The average particle diameter of the colloidal particle in a metal compound colloid can be set in the range which does not adversely affect the optical characteristic (for example, polarization characteristic) to a polarizing plate. 1-100 nm is preferable and, as for the average particle diameter of a colloidal particle, 1-50 nm is more preferable.

In addition, the average particle diameter of the said colloidal particle can be measured by the method similar to the method of obtaining the average primary particle diameter of the above-mentioned microparticles | fine-particles.

These ranges can uniformly disperse the colloidal particles in the adhesive layer. This ensures adhesion and suppresses the occurrence of knick defects. When a clic defect occurs, light omission occurs, for example, in the image display apparatus equipped with the polarizing plate.

The metal compound is not limited, and for example, oxides such as alumina, silica, zirconia, titania and the like; Metal salts such as aluminum silicate, calcium carbonate, magnesium silicate, zinc carbonate, barium carbonate and calcium phosphate; Minerals such as celite, talc, clay and kaolin. Metal compound colloids having an electrostatic charge are preferred. As the metal compound to be a colloid having an electrostatic charge, alumina and titania are preferable, and alumina is particularly preferable.

The metal compound colloid is generally a colloidal solution dispersed in a dispersion medium. The dispersion medium is, for example, water or alcohol. Solid content concentration in a colloidal solution is generally about 1-50 weight%, and 1-30 weight% is preferable. The colloidal solution may include an acid such as nitric acid, hydrochloric acid, acetic acid, etc. as a stabilizer.

As for the compounding quantity (solid content conversion) of the metal compound colloid in an adhesive composition, 200 weight part or less is preferable with respect to 100 weight part of PVA-type resin, 10-200 weight part is more preferable, 20-175 weight part is still more preferable, 30- 150 parts by weight is particularly preferred. These ranges further ensure the adhesion of the adhesive composition, and further suppress the occurrence of cunic defects.

The adhesive composition includes a coupling agent such as a silane coupling agent and a titanium coupling agent; Various tackifiers; Ultraviolet absorbers; Antioxidants; Stabilizers, such as a heat resistant stabilizer and a hydrolysis stabilizer, can be included.

The adhesive composition is preferably an aqueous solution (resin solution). The concentration of the resin in the aqueous solution is preferably from 0.1 to 15% by weight, more preferably from 0.5 to 10% by weight from the viewpoint of coatability and standing stability of the composition.

As for the viscosity of aqueous solution, 1-50 mPa * s is preferable. In the case where the adhesive composition contains a metal compound colloid, even if it is a low viscosity of 1 to 20 mPa · s, the occurrence of clic defects is effectively suppressed.

The pH of the aqueous solution is preferably 2 to 6, more preferably 2.5 to 5, still more preferably 3 to 5, and particularly preferably 3.5 to 4.5. In general, the surface charge of the metal compound colloid is adjusted by adjusting the pH of the aqueous solution. The surface charge is preferably an electrostatic charge. Since the static charge, the occurrence of the clic defect is further suppressed. The surface charge of the metal compound colloid can be confirmed, for example, by measuring the zeta potential with a zeta potential meter.

The adhesive composition which is an aqueous solution (resin solution) can be formed by a well-known method. When an adhesive composition contains a crosslinking agent and a metal compound colloid, the method of mix | blending a metal compound colloid with the solution which mixed PVA system resin and a crosslinking agent to the appropriate density | concentration, for example is taken. After mixing the PVA-based resin and the metal compound colloid, the crosslinking agent may be mixed while considering the use time of the adhesive composition. The concentration of the aqueous solution is adjustable after preparing the aqueous solution.

The thickness of the adhesive layer (adhesive layer) formed from the adhesive composition can be appropriately set according to the composition of the composition. The thickness is preferably 10 to 300 nm, more preferably 10 to 200 nm, particularly preferably 20 to 150 nm. In this range, the adhesive layer (adhesive layer) exhibits sufficient adhesive force.

[3. Image display device]

The image display device of the present invention has a polarizing plate according to the present invention. Image display devices such as electroluminescent (EL) display panels, plasma display panels (PDPs), field emission displays (FEDs), and LCDs.

The structure of the image display apparatus (image display apparatus of the invention) which has a polarizing plate which concerns on this invention is not specifically limited, It can have suitably members, such as a power supply, a backlight part, an operation part, as needed.

[4. Manufacturing Method of Optical Film]

The method for producing an optical film according to the present invention is a step of forming a coating film of the composition by applying an easy adhesive composition containing a polyester-acrylic composite resin (B) to a main surface (surface) of an acrylic resin film (coating step) And drying the formed coating film to form an easy adhesive layer containing the polyester-acrylic composite resin (B) on the surface (drying step). The easy adhesive composition may contain the above-mentioned particles.

In the method for producing an optical film according to the present invention, an optical film (optical film of the present invention) formed of an acrylic resin film having an easy adhesive layer containing the polyester-acrylic composite resin (B) on a main surface (surface) is formed. The easy adhesive layer contains a resin contained in the easy adhesive composition.

In a coating process, the coating film of an easily bonding composition is formed in at least one main surface (surface) of an acrylic resin film. Generally, the said coating film is formed in one main surface (surface) of an acrylic resin film.

A well-known method can be applied to the method of apply | coating an easily adhesive composition in a coating process. The method is, for example, bar coating method, roll coating method, gravure coating method, rod coating method, slot orifice coating method, curtain coat method, fountain coat method. The thickness of the coating film formed in a coating process can be adjusted suitably according to the thickness required when the said coating film becomes an easily bonding layer.

It is preferable that the main surface (surface) to which the easily adhesive composition in an acrylic resin film is apply | coated is surface-treated. The surface treatment is as described above, but corona discharge treatment and plasma treatment are preferred. The conditions of the corona discharge treatment are not limited. 50-150 W / m <2> / min is preferable and, as for the electron irradiation amount in a corona discharge process, 70-100 W / m <2> / min is more preferable.

The drying step can be performed according to a known method. Drying temperature is typically 50 degreeC or more, 90 degreeC or more is preferable, and 110 degreeC or more is more preferable. By setting the drying temperature in these ranges, for example, an optical film excellent in color resistance (especially in an environment of high temperature and high humidity) is obtained. 200 degrees C or less is preferable, and, as for the upper limit of a drying temperature, 180 degrees C or less is more preferable.

When manufacturing an optical film which is a stretched film from an unstretched acrylic resin film according to the manufacturing method of this invention, and when manufacturing an optical film which is a biaxially stretched film from a uniaxially stretched acrylic resin film, at some point You need to stretch. The stretching of the acrylic resin film may be performed before the formation of the easy adhesive layer, or may be performed after the formation of the easy adhesive layer. Formation of an easily bonding layer and extending | stretching of an acrylic resin film can also be performed simultaneously.

Stretching of the acrylic resin film can be performed according to a well-known method. Stretching is, for example, uniaxial stretching or biaxial stretching.

Uniaxial stretching is the free end uniaxial stretching which typically changes the width direction (TD direction) of an acrylic resin film. The fixed end uniaxial stretching which fixed the change of the width direction of an acrylic resin film may be sufficient.

Biaxial stretching is typically continuous biaxial stretching, but simultaneous biaxial stretching, which simultaneously performs longitudinal and transverse stretching, can also be suitably used. Moreover, you may extend | stretch to diagonal direction with respect to a film roll. In addition, in this specification, extending | stretching of the flow direction (MD direction) of an acrylic resin film is called longitudinal stretch, and extending | stretching of the width direction (TD direction) is called lateral stretch. In the case of a strip | belt-shaped acrylic resin film, MD direction is the longitudinal direction of the said film.

A well-known drawing machine can be used for extending | stretching an acrylic resin film. The longitudinal stretching group is not particularly limited, but an oven stretching machine is preferable.

The oven longitudinal stretching machine generally consists of an oven and a conveying roll respectively provided at the inlet side and the outlet side of the oven. The resin film is stretched in the conveyance direction by providing a circumferential speed difference between the conveyance roll on the inlet side of the oven and the conveyance roll on the outlet side.

Although a transverse stretching machine is not specifically limited, A tenter stretching machine is preferable. Although a tenter drawing machine may be a grip type or a pin type | mold, since a tear of a resin film hardly produces, a grip type is preferable. A grip-type tenter drawing machine generally consists of a clip traveling device for lateral drawing and an oven. In the clip traveling apparatus, the resin film is conveyed in a state where the transverse end portion of the resin film is fitted with the clip. At this time, open the guide rail of the clip drive. The resin film is stretched in the lateral direction by widening the distance between the two left and right clips. In the grip-type tenter stretching machine, simultaneous biaxial stretching is also possible by providing a scaling function of the clip with respect to the conveying direction of the resin film. In addition, it may be an inclined stretching machine which draws in the conveying direction of the film at different speeds in the stretching direction of the resin film at different speeds.

As for extending | stretching temperature, Tg vicinity of the acrylic resin which comprises an acrylic resin film is preferable. Specifically, the range of Tg-30 ° C to Tg + 100 ° C is preferable, and the range of Tg-20 ° C to Tg + 80 ° C is more preferable. If the stretching temperature is less than Tg-30 ℃ may not be sufficient stretching ratio. When the stretching temperature exceeds Tg + 100 ° C, the resin constituting the film may flow, and stable stretching may not be performed.

The draw ratio defined by the area ratio is preferably 1.1 to 25 times, more preferably 1.3 to 10 times. When the draw ratio is less than 1.1 times, the improvement of the properties of the optical film expected by the stretching, for example, the toughness, may not be realized. On the other hand, when the draw ratio is more than 25 times, the effect of improving the characteristics of the optical film is usually no longer obtained.

The stretching speed is preferably 10 to 20,000% / min, more preferably 100 to 10,000% / min with respect to unidirectional stretching. If the stretching speed is less than 10% / minute, the time required for stretching the film becomes too long, and the manufacturing cost of the optical film may increase. If the stretching speed exceeds 20,000% / min, the film may break.

When simultaneously forming the easily adhesive layer and stretching the acrylic resin film, for example, an acrylic resin film having a coating film of the easily adhesive composition can be stretched under a heating atmosphere after the coating step. The coating film of the easily bonding composition formed on the surface of the acrylic resin film is dried by the heat applied to the film for stretching, thereby forming the easily bonding layer. In addition, since Tg of an acrylic resin film is 100 degreeC or more normally, the above-mentioned extending | stretching temperature is temperature high enough for an easy adhesive layer to be formed from the coating film of an easily adhesive composition.

The acrylic resin film which forms the coating film of an easily bonding composition in a coating process may be an unstretched film, or the stretched film which has already been stretched. When the acrylic resin film which forms a coating film is a strip | belt-shaped uniaxial stretched film, and produces an optical film which is a biaxially stretched film, the uniaxial stretching direction is MD direction of the said film, and the extending | stretching direction after forming a coating film is its TD direction. It is preferable. As a result, an efficient optical film can be produced.

When forming an acrylic resin film by melt extrusion, the process from formation of an acrylic resin film to obtaining an optical film which is a stretched film can be performed continuously. In this case, it is preferable to continuously perform the process of apply | coating the easily adhesive composition to the surface of an acrylic resin film, and the process of extending | stretching the acrylic resin film which apply | coated the easily adhesive composition under heat environment. The application process of such easily carried out easy adhesive composition is called in-line coating.

When manufacturing the optical film which is a biaxially stretched film by the manufacturing method of this invention, the process of extending | stretching an unstretched film to the acrylic resin film which is a uniaxially stretched film, the process of apply | coating an easily adhesive composition to the surface of the said acrylic resin film, And it is especially preferable to continuously perform the process of extending | stretching the acrylic resin film which apply | coated the easily adhesive composition in a heating atmosphere.

When the acrylic resin film is subjected to surface treatment such as corona discharge treatment or plasma treatment, the unstretched film is stretched to an acrylic resin film which is a uniaxially stretched film, and the surface treatment of the surface of the acrylic resin film is performed. It is preferable to continuously perform the process of apply | coating the easily adhesive composition to the said surface of the processed acrylic resin film, and the process of extending | stretching the acrylic resin film which apply | coated the easily adhesive composition in a heating atmosphere.

The manufacturing method of this invention can include arbitrary processes other than the process mentioned above as long as the effect of this invention can be acquired. The said process is a process of laminating | stacking an additional layer (for example, resin layer) with respect to the formed optical film, or the process of performing post-processing, such as a coating process and a surface treatment, with respect to the formed optical film.

The present invention is not limited to the above-described embodiments, but various modifications are possible within the scope shown in the claims, and the embodiments obtained by appropriately combining the technical means disclosed in the other embodiments are also included in the technical scope of the present invention. do.

Example

Hereinafter, the present invention will be described in more detail with reference to Examples. The invention is not limited to the following examples. First, the evaluation method of the polymer, the optical film, and the optical film roll produced in the present Example is shown.

System: Toshiba GPC System HLC-8220

Measurement side column configuration

Guard column: manufactured by Tosoh Corp, TSKguardcolumn SuperHZ-L

Separation column: Tosoh, TSKgel SuperHZM-M 2 serial connection

   Reference side column configuration

   Reference column: Tosoh, TSKgel SuperH-RC

Developing solvent: Chloroform (made by Wako Pure Chemical Industries, Limited)

Flow rate of developing solvent: 0.6mL / min

Standard sample: TSK standard polystyrene (made of plastic, PS-oligomer kit)

Column temperature: 40 ℃

[Glass Transition Temperature (Tg)

The Tg of the polymer was determined by the initial point law in accordance with the provisions of JIS K7121. Specifically, a differential scanning calorimeter (manufactured by Rigaku, DSC-8230) was used to evaluate a sample of about 10 mg under a nitrogen gas atmosphere from a DSC curve obtained by raising the temperature (at a rate of 20 ° C / min) from room temperature to 200 ° C. Α-alumina was used as a reference.

[Film thickness]

The thickness of the film was measured using Dejima micrometer (made by Mitutoyo Co., Ltd.). Then, the sample for measuring and evaluating the physical property of the film including the physical property which shows an evaluation method was obtained from the center part of the width direction of a film.

[Average Particle Diameter and Particle Size Distribution of Particles]

The average particle diameter and particle size distribution of the fine particles were evaluated using a particle size distribution measuring apparatus (manufactured by Particle Sizing Systems, Submicron Particle Sizer NICOMP380). Specifically, with respect to the fine particles dispersed in water, the equivalent spherical distribution in the range of 100 nm or more is measured by the measuring apparatus as the primary basic particle diameter, and on the large particle side in the obtained distribution. The particle diameter of the particle | grains of 50% of accumulated integrated volume fractions was calculated | required, and this was made into the average primary particle diameter (d50) of microparticles | fine-particles. Apart from this, the particle size (d25) of the particles having a cumulative volume fraction of 25% and the particle size (d75) of the particles (75%) of 75%, which are accumulated on the large particle side in the above distribution, are obtained, and the ratio (d25 / d75) is determined by the particle size distribution of the fine particles. It was set as.

[Haze]

The haze of the produced film was calculated | required based on the provision of JISK7136 using the turbidity meter (made by Japan Coloring Industry, NDH-5000).

[Light Transmittance at Wavelength of 380nm]

The light transmittance at a wavelength of 380 nm was measured using an ultraviolet visible spectrophotometer (manufactured by Shimadzu Corporation, UV-3100).

[Hard Coat Layer Adhesiveness]

The board test was done based on JISK5400 3.5. Specifically, after inserting a 1 mm square checkerboard notch with a sharp blade on the hard coat layer surface, a cellophane tape of 25 mm width in accordance with JIS Z1522 was adhered with a wooden spatula, and then the cellophane tape was removed. Of the 100 masses produced, the number of squares remaining is shown in the "Adhesiveness" column of Tables 1 and 2 below.

The cellophane tape is a commercially available cellophane tape that has passed JIS Z1522.

Adhesion with an Adhesive Adhesive Layer

Polyvinyl alcohol-based resin (average degree of polymerization 1200) was dissolved in pure water to obtain an adhesive composition having a solid content of 4%. The obtained adhesive composition is applied to the easy adhesive layer (b) formed on the surface of the optical film on the side opposite to the surface on which the hard coating layer is formed, so as to have a thickness of 50 nm after drying, and then introduced into a hot air dryer at 80 ° C. for 5 minutes. The film was obtained by drying.

Using the film obtained by the said method as a test sample, the board | substrate test was done based on JISK5400 3.5. Specifically, after inserting a 1 mm square checker-shaped notch with a sharp blade on the adhesive layer surface of the test sample, a 25 mm wide cellophane tape in accordance with JIS Z1522 was brought into close contact with a wooden spatula. After that, the cellophane tape was removed and the state of the layer was observed. Evaluation criteria are as follows.

(Circle): Peeling was not confirmed.

X: Peeling was confirmed.

[Strength strength]

Break strength of the film was performed according to JIS P8115. Specifically, two types of test films having a length of 90 mm and a width of 15 mm whose longitudinal directions are the MD direction and the TD direction are left to stand at 23 ° C. and 50% RH for at least 1 hour, and then used. (Be-201 type), and the test is conducted so that the bending line is parallel to the flow direction of the film at the time of film forming under the condition of 200 g of the load, until the five sample films break. The average value of the number of times was taken as a measurement result.

(Manufacture example 1)

40 parts by weight of methyl methacrylate (MMA), 10 parts by weight of methyl 2- (hydroxymethyl) acrylate (MHMA), a toluene 50 as a polymerization solvent, in a reaction tank equipped with a stirring device, a temperature sensor, a cooling tube and a nitrogen introduction pipe. The weight part and 0.025 weight part of antioxidants (made by ADEKASTAB 2112, ADEKA) were put into it, and it heated up to 105 degreeC, passing nitrogen through this. At the start of reflux at elevated temperature, 0.05 parts by weight of t-amylperoxyisononanoate (Arke Mayo-Shitomi, trade name: Luperose 570) was added as a polymerization initiator, and the t-amylperoxyisonanoate 0.10 was added. The solution polymerization was carried out under reflux at about 105 to 110 ° C. while the weight part was added dropwise over 2 hours, and further aged for 4 hours.

Next, 0.05 part by weight of stearyl phosphate (manufactured by Sakai Chemical, Phoslex A-18) was added as a catalyst (cyclization catalyst) for the cyclization condensation reaction to the obtained polymerization solution, and the lactone ring structure was carried out at reflux of about 90 to 110 ° C for 2 hours. Cyclic condensation reaction was carried out to form.

Subsequently, after completing the cyclization condensation reaction of the polymer solution obtained in the cyclization condensation reaction through a multi-tube heat exchanger heated to 240 ° C, the barrel temperature 240 ° C, a reduced pressure of 13.3 to 400 hPa (10 to 300mmHg), and rear vent 1 number and 4 pore vents (first, second, third, and fourth vents on the upstream side). In the vent type screw twin screw extruder (L / D = 52) with a side feeder installed between the third and fourth vents and a leaf disc polymer filter (filtration accuracy of 5 μm) at the tip, 88 parts / hour ( Devolatilization was carried out by introducing at a processing rate in terms of resin amount).

At that time, ion exchange water was added behind the second vent at an input rate of 1.3 parts / hour, and a cyclization catalyst deactivator solution prepared separately was placed behind the third vent at an input rate of 0.6 parts / hour. A mixed solution of the ultraviolet absorber and the antioxidant was added at the back of the fourth vent at an injection rate of 2.7 parts / hour.

As the cyclization catalyst deactivator solution, a solution obtained by dissolving 1.0 parts by weight of calcium octylate (5% by weight of Nippa Octix calcium, manufactured by Nippon Chemical Industries, Ltd.) as a deactivator was used in 1.8 parts by weight of toluene.

The mixed solution of the ultraviolet absorber and the antioxidant is 0.1 parts by weight of a phenolic antioxidant (BASF Japan, Irganox 1010). 0.1 part by weight of sulfur-based antioxidant (ADEKASTAB AO-412S). 8.55 parts by weight of a UV absorber (BASF Japan, Chinuvin 477) and a solution dissolved in 3.56 parts by weight of toluene were used.

In addition, pellets of styrene-acrylonitrile copolymer (AS resin: styrene unit / acrylonitrile unit ratio of 73 wt% / 27 wt%, weight average molecular weight 220,000) were devised in the side feeder during devolatilization. It was introduced at a feed rate of parts / hour.

After completion of the devolatilization, the heat-melt resin remaining in the extruder is discharged while being filtered through a polymer filter from the tip of the extruder, and pelletized by a molding granulator to form a (meth) acrylic polymer having a lactone ring structure in the main chain. The transparent pellet (A1) of the acrylic resin which made the (content rate 78 weight%) and further contains the styrene acrylonitrile copolymer in the content rate of 12 weight% was obtained. Tg of the acrylic resin which comprises pellet (A1) was 124 degreeC, and the weight average molecular weight was 14.9 million.

Next, the produced pellet A1 was melt-extruded in a T die at 280 degreeC using the single screw extruder, and it discharged on the 110 degreeC cooling roll, and formed the film of 174 micrometers in thickness. Next, the film thus formed was uniaxially stretched at the free end at 136 ° C. in the MD direction so that the draw ratio was 2.2 times to obtain a longitudinally stretched film F1 having a thickness of 116 μm.

(Manufacture example 2)

Melt extrusion was carried out in a T-die at 280 ° C using an acrylic resin (Diesel Evonik, Frekisiimide 8813, manufactured by Daicel Evonik, 8813) having a (meth) acrylic polymer having a glutarimide structure as a main component. It discharged on the cooling roll of degreeC, and formed the film of 174 micrometers in thickness. Next, the film thus formed was uniaxially stretched at the free end at 142 ° C. in the MD direction so that the draw ratio was 2.2 times to obtain a longitudinally stretched film (F2) having a thickness of 116 μm.

(Manufacture example 3)

Polyester-acrylic composite resin having an epoxy group and a carboxyl group (manufactured by Takamatsu Oil Co., Ltd., Pesresin A-647GEX, solid content 20% by weight) 75 parts by weight, emulsion containing amorphous silica particles (Japan catalyst, Shihostar KE-W10 average A particle size (primary particle diameter) of 0.11 μm, a particle size distribution of 1.1, a solid content of 15% by weight) and 1.0 part by weight of pure water were mixed to obtain an easy adhesive composition (B1) which was an emulsion dispersion.

(Manufacture example 4)

75 parts by weight of polyester-acrylic composite resin having epoxy group and carboxyl group (manufactured by Takamatsu Oil Holding Co., Pesresin A-645GEX, solid content 20% by weight), emulsion containing amorphous silica fine particles (Japan catalyst agent, Shihostar KE-W10 average The particle size (primary particle diameter) 0.11 micrometer, particle size distribution 1.1, 15 weight% of solid content) 1.0 weight part, and 74 weight part of pure waters were mixed, and the easily adhesive composition (B2) which is an emulsion-type dispersion was obtained.

(Manufacture example 5)

Polyester-acrylic composite resin having an epoxy group and a carboxyl group (manufactured by Takamatsu Oil Co., Ltd., Pesresin A-645GLX, solid content 20 wt%) 75 parts by weight, emulsion containing amorphous silica particles (Japan catalyst, Shihostar KE-W10 average The particle size (primary particle diameter) 0.11 micrometer, particle size distribution 1.1, 15 weight% of solid content) 1.0 weight part, and 74 weight part of pure waters were mixed, and the easily adhesive composition (B3) which is a dispersion of an emulsion form was obtained.

(Manufacture example 6)

37.5 parts by weight of polyester-acrylic composite resin having epoxy group and carboxyl group (manufactured by Takamatsu Oil Co., Ltd., psresin A-647GEX, solid content 20% by weight), polyester-acrylic composite resin (manufactured by Takamatsu Oil Co., Ltd., p-resin A-645GH, 30 parts by weight solids) 25 parts by weight, emulsion containing amorphous silica particles (manufactured by Nippon Catalyst, Shihostar KE-W10, average particle diameter (primary particle diameter) 0.11μm, particle size distribution 1.1, solids content 15% by weight) 1.0 parts by weight and 86.5 parts by weight of pure water was mixed to obtain an easy adhesive composition (B4) as a dispersion in the form of an emulsion.

(Manufacture example 7)

23 parts by weight of a urethane resin (Daiichi Kogyo Pharmaceutical Co., Ltd., Superflex 210, 35% by weight solid), 16 parts by weight of a crosslinking agent (Japan catalyst, Epocross WS-700, 25% by weight solid), emulsion containing amorphous silica particles (Japanese catalyst, Shihostar KE-W30, average particle diameter (primary particle diameter) 0.28μm, particle size distribution 1.1, solid content 20% by weight) 0.03 parts by weight and 61 parts by weight of pure, easy adhesive composition as a dispersion in the form of emulsion ( B5) was obtained.

(Manufacture example 8)

15 parts by weight of a tetrafunctional acrylate (manufactured by New Nakamura Chemical Co., Ltd., AD-TMP), 0.6 parts by weight of a photopolymerization initiator (Shiba Specialty Chemical, Irgacua 184), and 14.4 parts by weight of methyl ethyl ketone are mixed to form a coating composition for a hard coat ( C1) was obtained.

(Manufacture example 9)

229.6 parts by weight of methyl methacrylate (MMA), 33 parts by weight of methyl 2- (hydroxymethyl) acrylate (MHMA) in a reaction tank having a stirring device, a temperature sensor, a cooling tube and a nitrogen introduction tube, 248.6 weight of toluene as a polymerization solvent. To this, 0.138 parts by weight of an antioxidant (ADECASTAB 2112, manufactured by ADEKA) and 0.1925 parts by weight of n-dodecyl mercaptan were added, and the temperature was raised to 105 ° C while passing nitrogen.

At the beginning of the reflux at elevated temperature, 0.2838 parts by weight of t-amyl peroxy isononanoate (manufactured by Arkema Yoshitomi, trade name: Luperox 570) was added, and the t-amylperoxyisonanoate was added. While 0.5646 weight part and 12.375 weight part of styrene were dripped over 2 hours, solution polymerization was advanced under reflux of about 105-110 degreeC, and further aged for 4 hours.

Next, 0.206 parts by weight of stearyl phosphate (manufactured by Sakai Chemical, Phoslex A-18) was added as a catalyst (cyclization catalyst) for the cyclization condensation reaction to the obtained polymerization solution, and the lactone ring structure was carried out at reflux of about 90 to 110 ° C for 2 hours. Cyclic condensation reaction was carried out to form.

Subsequently, the polymer solution obtained in the cyclization condensation reaction was heated to 240 ° C., and then the cyclization condensation reaction was completed through a multi-tube heat exchanger. Then, the barrel temperature was 250 ° C., the pressure reduction degree was 13.3 to 400 hPa (10 to 300 mmHg), and the number of rear vents was 1. And a number of pore vents (referred to as first, second, third and fourth vents on the upstream side), side feeders are provided between the third and fourth vents, and a leaf disc polymer filter ( A vent type screw twin screw extruder (L / D = 52) having a filtration precision of 5 m) was introduced at a processing speed of 31.2 parts / hour (resin amount conversion) and devolatilized.

At that time, the chlorinated catalyst deactivator solution prepared separately from the second vent at an input rate of 0.47 parts / hour was prepared from the UV absorber solution from behind the third vent at an input rate of 0.18 parts / hour. Each was charged behind the fourth vent at an injection rate of 0.59 parts / hour.

The cyclization catalyst deactivator solution used a solution obtained by dissolving 53.4 parts by weight of calcium octylate (5% by weight of Nippa Octix calcium, manufactured by Nippon Chemical Industries, Ltd.) as 124.5 parts by weight of toluene. As a ultraviolet absorber solution, the solution which melt | dissolved 0.66 weight part of ultraviolet absorbers (made by ADEKA, Adecastar LA-F70) in 1.23 weight part of toluene was used.

After completion of the devolatilization, the heat-melt resin left in the extruder is discharged while filtered by a polymer filter at the tip of the extruder, and pelletized by a molded granulator to form a (meth) acrylic polymer having a lactone ring structure in the cast iron. A transparent pellet (A2) of resin was obtained. Tg of the acrylic resin which comprises pellet (A2) was 121 degreeC, and the weight average molecular weight was 13.1 million.

Next, the produced pellets (A2) were melt-extruded in a T die at 280 ° C using a single screw extruder, and discharged onto a 110 ° C cooling roll to form a film of 174 μm thick. Next, the film formed into a film was uniaxially stretched at the free end at 136 degreeC in MD direction so that draw ratio might be 2.2 times, and the longitudinal stretched film (F19) of 116 micrometers in thickness was obtained.

(Manufacture example 10)

100 parts by weight of an acrylic resin having a (meth) acrylic polymer having a glutaric anhydride structure in its main chain (Sumitomo Chemical, Sumipex TR) and 0.66 parts by weight of an ultraviolet absorber (ADEKA, Adecastab LA-F70) Was supplied to a twin screw extruder at 240 degreeC, and the transparent pellet (A3) of the acrylic resin which consists of a (meth) acryl polymer which has a glutaric anhydride structure in a principal chain was obtained.

Subsequently, melt extrusion was performed at 260 degreeC by T die using a single screw extruder, and it discharged on the 110 degreeC cooling roll, and formed the film of 174 micrometers in thickness. Next, the film thus formed was uniaxially stretched at the free end at 136 ° C. in the MD direction so that the draw ratio was 2.2 times to obtain a longitudinally stretched film (F20) having a thickness of 116 μm.

(Manufacture example 11)

37.5 parts by weight of a polyester-acrylic composite resin having an epoxy group and a carboxyl group (manufactured by Takamatsu Oil, Inc., psresin A-647GEX, solid content 20% by weight), polyester-acrylic composite resin having an epoxy group and not having a carboxyl group , Psresin A-645GH, solid content 30% by weight) 25 parts by weight, emulsion containing amorphous silica particles (manufactured by Nissan Chemical Industries, Snowtex XL, average particle diameter (primary particle diameter) 50nm, solid content 40% by weight) 0.375 parts by weight And 237 parts by weight of pure water was mixed to obtain an easy adhesive composition (B6) which is a dispersion in the form of an emulsion.

(Manufacture example 12)

30 parts by weight of a polyester-acrylic composite resin having an epoxy group and a carboxyl group (manufactured by Takamatsu Oil Co., Ltd., Pestresin A-647GEX, 20 wt% solids), a polyester-acrylic composite resin having an epoxy group and having no carboxyl group , Psresin A-645GH, solids 30 wt%) 30 parts by weight, emulsion containing amorphous silica particles (Japan catalyst product, Sea host KE-W10, average particle diameter (primary particle diameter) 0.11μm, particle size distribution 1.1, solid content 15 Wt%) 1.0 parts by weight and 89 parts by weight of pure water were mixed to obtain an easy adhesive composition (B7) which is a dispersion in the form of an emulsion.

(Manufacture example 13)

30 parts by weight of a polyester-acrylic composite resin having an epoxy group and a carboxyl group (manufactured by Takamatsu Oil Co., Ltd., Pestresin A-647GEX, 20 wt% solids) 36% by weight of petroleum free resin A-647GH, solid content 25% by weight, emulsion containing amorphous silica particles (manufactured by Nippon Catalyst, Shihostar KE-W10, average particle diameter (primary particle diameter): 0.01 μm, particle size distribution 1.1, solid content) 15 weight%) 1.0 weight part and 83 weight part of pure waters were mixed, and the easily bonding composition (B8) which is a dispersion of an emulsion form was obtained.

(Production Example 14)

22.5 parts by weight of a polyester-acrylic composite resin having an epoxy group and a carboxyl group (manufactured by Takamatsu Oil Co., Ltd., Pesresin A-647GEX, solid content 20% by weight), a polyester-acrylic composite resin having an epoxy group and not having a carboxyl group , Psresin A-645GH, solid content 30% by weight) 35 parts by weight, emulsion containing amorphous silica particles (Japan catalyst product, Sea host KE-W10, average particle diameter (primary particle diameter) 0.11μm, particle size distribution 1.1, solid content 15 % By weight), 1.0 parts by weight of an emulsion containing amorphous silica particles (Nissan Chemical Industries, Snowtex C, average particle diameter (primary particle diameter) 15nm, solid content 20% by weight) 15 parts by weight and pure water 76.5 parts by mixing the emulsion form The easy adhesive composition (B9) which is a dispersion of was obtained.

(Production Example 15)

36.4 parts by weight of a urethane resin (Daiichi Industrial Products, Super Flex 210, 35% by weight of solids), 9 parts by weight of a crosslinking agent (Japanese catalyst product, Epocross WS-700, 25% by weight of solids), an emulsion containing amorphous silica particles ( Nippon Catalyst, Shihostar KE-W10, an average particle diameter (primary particle diameter) 0.11μm, particle size distribution 1.1, solid content 15% by weight) 1 part by weight and 103.6 parts by weight of a pure, easily adhesive composition (B10) Got.

(Manufacture example 16)

60 parts by weight of polyester resin (manufactured by Takamatsu Oil Co., Ltd., psresin A-640, solid content 25% by weight), emulsion containing amorphous silica particles (Japan catalyst product, Shihostar KE-W10, average particle diameter (primary particle diameter) 0.11 1 part by weight of μm, a particle size distribution of 1.1, and 15 parts by weight of solid content) and 89 parts by weight of pure water were mixed to obtain an easy adhesive composition (B11) which is a dispersion in the form of an emulsion.

(Manufacture example 17)

48.4 parts by weight of an acrylic resin (Japan catalyst, acrylic set WR705, solid content 31% by weight), emulsion containing amorphous silica particles (Japan catalyst, Seastar KE-W10, average particle diameter (primary particle diameter) 0.11μm, particle size distribution 1.1 parts by weight, 15 parts by weight of solid content) and 100.6 parts by weight of pure water were mixed to obtain an easy adhesive composition (B12) as a dispersion in the form of an emulsion.

(Manufacture example 18)

100 parts by weight of an acrylic resin having a (meth) acrylic polymer having a glutarimide structure in its main chain (Diecel Evonik, Plexiimide 8813) and a 0.66 part by weight ultraviolet absorber (ADEKASTAB LA) -F70) was fed to a twin screw extruder at 260 degreeC, and the transparent pellet (A4) of the acrylic resin which consists of a (meth) acryl polymer which has a glutarimide structure in the principal chain was obtained.

Subsequently, melt extrusion was performed at 280 degreeC by the T die using the single screw extruder, and it discharged to the 110 degreeC cooling roll, and formed the film of 174 micrometers in thickness. Next, the film thus formed was uniaxially stretched at the free end at 142 ° C. in the MD direction so that the draw ratio was 2.2 times to obtain a longitudinally stretched film (F43) having a thickness of 116 μm.

(Example 1)

After applying the easy adhesive composition (B1) prepared in Preparation Example 3 to one main surface of the longitudinally stretched film (F1) prepared in Preparation Example 1 so that the thickness of the coating film was 260 nm, the draw ratio was 2.8 times. The fixed end uniaxial stretching was carried out at 146 degreeC in the TD direction using the tenter stretching machine, and the biaxially stretched optical film (F3) which has an easily bonding layer (a) in the cross section was obtained. The haze of the obtained film (F3) was 41%.

Next, after drying the coating composition (C1) prepared in Preparation Example 8, the film (F3) side of the easy adhesive layer (a) was applied to the opposite side (the easy adhesive layer surface) for 2 minutes at 100 ° C so that the thickness of the coating film was 4 μm. Dried.

Subsequently, UV light having an integrated irradiation amount of 500 mJ / m 2 was irradiated to cure the coating composition (C1) to obtain a hard coat layer on the surface of the optical film (F4). The haze of the obtained film (F4) was 0.5%, and the light transmittance of wavelength 380 nm was 8%. The adhesiveness of the hard coat layer was 100. The fracture strength was 360 times in MD and 316 in TD.

(Example 2)

A biaxially stretched optical film having an easy adhesive layer (a) in the cross section by performing the same operation as in Example 1 except that the easy adhesive composition (B2) prepared in Preparation Example 4 was used instead of the easy adhesive composition (B1). (F5) and the optical film (F6) which has a hard-coat layer on the surface. The haze of the obtained films (F5) and (F6) was 23% and 0.3%, respectively, and the light transmittance at the wavelength of 380 nm was 8%. The adhesiveness of the hard coat layer was 100.

(Example 3)

Instead of the easy adhesive composition (B1), except that the easy adhesive composition (B3) prepared in Preparation Example 5 was used, by carrying out the same operation as in Example 1, biaxial stretching having an easy adhesive layer (a) in the cross section An optical film (F7) and an optical film (F8) having a hard coat layer on the surface were obtained. The haze of the obtained films (F7) and (F8) was 0.4% and 0.5%, respectively, and the light transmittance of wavelength 380 nm was 8%. The adhesiveness of the hard coat layer was 90.

(Example 4)

A biaxially stretched optical having an easy adhesive layer (a) in the cross section by performing the same operation as in Example 1, except that the easy adhesive composition (B4) prepared in Preparation Example 6 was used instead of the easy adhesive composition (B1). The film (F9) and the optical film (F10) which have a hard-coat layer on the surface were obtained. The haze of the obtained films (F9) and (F10) was 0.6% and 0.5%, respectively, and the light transmittance at the wavelength of 380 nm was 8%. The adhesiveness of the hard coat layer was 100.

(Example 5)

On one main surface of the longitudinally stretched film (F1) prepared in Production Example 1, the easy adhesive composition (B4) prepared in Production Example 6 was applied so as to have a thickness of the coating film after drying, and to the other main surface. The easy adhesive composition (B5) prepared in was coated with a coating film thickness of 1250 nm after drying.

Subsequently, the fixed end was uniaxially stretched at 146 degreeC in the TD direction using a tenter drawing machine so that draw ratio might be 2.8 times, and the biaxially stretched optical film (F11) which has an easily bonding layer on both surfaces was obtained. That is, in the biaxially stretched optical film F11, the easily bonding layer (a) is formed in one surface, and the easily bonding layer (b) is formed in the surface on the opposite side to the surface in which the easily bonding layer (a) is formed. The haze of the obtained film (F11) was 0.6%.

Next, the coating composition (C1) prepared in Production Example 8 was dried on the surface on the opposite side of the biaxially stretched optical film (F11) side of the easy adhesive layer (a), and the thickness of the coating film after drying was 4 μm. It applied so that it might become and dried at 100 degreeC for 2 minutes.

Subsequently, UV light having a cumulative irradiation amount of 500 mJ / cm 2 was irradiated to cure the coating composition (C1), thereby obtaining an optical film (F12) having a hard coat layer on the surface and an easy adhesive layer (b) on the opposite side.

The haze of the obtained film (F12) was 0.5%, and the light transmittance of wavelength 380 nm was 8%. The adhesiveness of the hard-coat layer was 100, and the adhesiveness of the adhesive bond layer was (circle).

(Example 6)

After applying the easy adhesive composition (B4) prepared in Preparation Example 6 to one main surface of the longitudinally stretched film (F2) prepared in Preparation Example 2 so that the thickness of the coating film after drying was 260 nm, the tenter was stretched to 2.8 times. The fixed uniaxial stretching was carried out at 152 degreeC in the TD direction using the drawing machine, and the biaxially stretched optical film (F13) which has an easily bonding layer (a) in the cross section was obtained. The haze of the obtained film (F13) was 2.7%.

Next, the coating composition (C1) prepared in Preparation Example 8 was dried on the surface on the opposite side of the film (F13) side of the easy adhesive layer (a) so as to have a thickness of 4 μm after drying. And dried at 100 ° C. for 2 minutes.

Subsequently, UV light having a cumulative irradiation amount of 500 mJ / cm 2 was irradiated to cure the coating composition (C1) to obtain an optical film (F14) having a hard coat layer on the surface. The haze of the obtained film (F14) was 0.7%. The adhesiveness of the hard coat layer was 100.

(Example 7)

Instead of the longitudinally stretched film F1, the same operation as in Example 4 was carried out except that the longitudinally stretched film F19 prepared in Production Example 9 was used, so that the biaxially having an easy adhesive layer (a) on the cross section. The stretched optical film (F21) and the optical film (F22) which have a hard-coat layer were obtained.

The haze of the obtained films (F21) and (F22) was 2.2% and 0.3%, respectively, and the adhesiveness of the hard-coat layer was 100. The light transmittance at the wavelength of 380 nm was 8%.

(Example 8)

Instead of the longitudinally oriented film F1, except that the longitudinally oriented F20 fabricated in Production Example 10 was used, the same operation as in Example 4 was carried out so that the biaxially having an easy adhesive layer (a) in the cross section. Stretched optical film (F23) and optical film (F24) having a hard coat layer were obtained.

Haze of obtained films (F23) and (F24) was 2.5% and 0.3%, respectively, and the adhesiveness of the hard-coat layer was 100. The light transmittance at the wavelength of 380 nm was 8%.

(Example 9)

After applying the easy adhesive composition (B6) prepared in Preparation Example 11 to one main surface of the longitudinally stretched film F1 prepared in Preparation Example 1 so that the thickness of the coating film was 130 nm, the draw ratio was 2.8 times. The tenter was uniaxially stretched at the fixed end part at 146 degreeC in the TD direction, and the biaxially stretched optical film (F25) which has an easily bonding layer (a) in the cross section was obtained. The haze of the obtained film (F25) was 0.8%.

Next, the coating composition (C1) prepared in Production Example 8 was dried on the surface on the side opposite to the surface on the biaxially stretched optical film (F25) side of the easy adhesive layer (a), and the thickness of the coating film after drying It applied so that it might become 4 micrometers, and it dried at 100 degreeC for 2 minutes.

Subsequently, UV light with an integrated irradiation amount of 500 mJ / cm 2 was irradiated to cure the coating composition (C1) to obtain an optical film (F26) having a hard coat layer on the surface. The haze of the obtained film (F26) was 0.2%, and the light transmittance at the wavelength of 380 nm was 8%. The adhesiveness of the hard coat layer was 100.

(Example 10)

Biaxially stretched optical having an easy adhesive layer (a) on the cross section by performing the same operation as in Example 1, except that the easy adhesive composition (B7) prepared in Preparation Example 12 was used instead of the easy adhesive composition (B1). An optical film (F28) having a film (F27) and a hard coat layer was obtained.

Haze of obtained films (F27) and (F28) was 1.2% and 0.2%, respectively, and the adhesiveness of the hard-coat layer was 100. The light transmittance at the wavelength of 380 nm was 8%.

(Example 11)

A biaxially stretched optical film having an easy adhesive layer (a) in the cross section by performing the same operation as in Example 1 except that the easy adhesive composition (B8) prepared in Preparation Example 13 was used instead of the easy adhesive composition (B1). An optical film (F30) having (F29) and a hard coat layer was obtained.

Haze of obtained films (F29) and (F30) was 0.6% and 0.2%, respectively, and the adhesiveness of the hard-coat layer was 100. The light transmittance at a wavelength of 380 nm was 8%.

(Example 12)

A biaxially stretched optical film having an easy adhesive layer (a) in the cross section by performing the same operation as in Example 1 except that the easy adhesive composition (B9) prepared in Preparation Example 14 was used instead of the easy adhesive composition (B1). An optical film (F32) having (F31) and a hard coat layer was obtained.

Haze of obtained films (F31) and (F32) was 1.1% and 0.1%, respectively, and the adhesiveness of the hard-coat layer was 100. The light transmittance at a wavelength of 380 nm was 8%.

(Example 13)

Instead of the longitudinally oriented film F2, by carrying out the same operation as in Example 6 except that the longitudinally oriented film F43 prepared in Production Example 18 was used, the biaxially having an easy adhesive layer (a) in the cross section. An optical film (F45) having a stretched optical film (F44) and a hard coat layer was obtained.

Haze of obtained films (F44) and (F45) was 2.8% and 0.2%, respectively, and the adhesiveness of the hard-coat layer was 100. The light transmittance at a wavelength of 380 nm was 8%.

(Comparative Example 1)

The biaxially stretched optical film (F15) which does not have an easy adhesive layer by uniaxially stretching the longitudinally stretched film (F1) produced in Production Example 1 at 146 ° C in the TD direction using a tenter stretching machine to have a draw ratio of 2.8 times Got it. The haze of the obtained film (F15) was 0.2%.

Next, the coating composition (C1) prepared in Preparation Example 8 was applied to one main surface of the film F15 so as to have a thickness of 4 μm after drying, and dried at 100 ° C. for 2 minutes.

Subsequently, UV light of a cumulative irradiation amount of 500 mJ / cm 2 was irradiated to cure the coating composition (C1) to obtain an optical film (F16) having a hard coat layer on the surface. The haze of the obtained film (F16) was 0.2%. The adhesiveness of the hard coat layer was 30. The fracture strength was 287 MD and 245 TD.

(Comparative Example 2)

The longitudinal stretched film (F2) prepared in Production Example 2 was uniaxially stretched at 152 ° C in the TD direction using a tenter stretching machine so that the draw ratio was 2.8 times, thereby obtaining a biaxially stretched optical film (F17) having no easy adhesive layer. . The haze of the obtained film (F18) was 1.2%.

Next, the coating composition (C1) prepared in Production Example 8 was applied to one main surface of the film F17 so as to have a thickness of 4 μm after drying, and dried at 100 ° C. for 2 minutes.

Subsequently, UV light with an integrated irradiation amount of 500 mJ / cm 2 was irradiated to cure the coating composition (C1), thereby obtaining an optical film (F18) having a hard coat layer on its surface. The haze of the obtained film (F18) was 0.8%. The adhesiveness of the hard coat layer was 30.

(Comparative Example 3)

Instead of the longitudinally stretched film (F1), except that the longitudinally stretched film (F19) prepared in Preparation Example 9 was carried out by the same operation as Comparative Example 1, biaxially stretched optical film having no easy adhesive layer ( F33) and an optical film (F34) having a hard coat layer. The haze of the obtained films (F33) and (F34) was 0.2% and 0.5%, respectively, and the adhesiveness of the hard-coat layer was 20.

(Comparative Example 4)

A biaxially stretched optical film having no easy adhesive layer by performing the same operations as Comparative Example 1 except for using the longitudinally stretched film F20 prepared in Preparation Example 10 instead of the longitudinally stretched film F1 ( F35) and an optical film (F36) having a hard coat layer. The haze of the obtained films (F35) and (F36) was 0.2% and 0.7%, respectively, and the adhesiveness of the hard-coat layer was 15.

(Comparative Example 5)

A biaxially stretched optical film having an easy adhesive layer (a) in the cross section by performing the same operation as in Example 1 except that the easy adhesive composition (B10) prepared in Preparation Example 15 was used instead of the easy adhesive composition (B1). An optical film (F38) having (F37) and a hard coat layer was obtained. Haze of obtained films (F37) and (F38) was 0.2% and 1.3%, respectively, and the adhesiveness of the hard-coat layer was 3.

(Comparative Example 6)

The biaxially stretched optical film F39 having an easy adhesive layer on its cross section by performing the same operation as in Example 1 except that the easy adhesive composition (B11) prepared in Preparation Example 16 was used instead of the easy adhesive composition (B1). ) And an optical film (F40) having a hard coat layer. The haze of the obtained films (F39) and (F40) was 0.5% and 1.2%, respectively, and the adhesiveness of the hard-coat layer was 20.

(Comparative Example 7)

A biaxially stretched optical film having an easy adhesive layer on its cross section by performing the same operation as in Example 1, except that the easy adhesive composition (B12) prepared in Preparation Example 17 was used instead of the easy adhesive composition (B1). F41) and an optical film (F42) having a hard coat layer. The haze of the obtained films (F41) and (F42) was 0.5% and 1.2%, respectively, and the adhesiveness of the hard-coat layer was 12.

(Comparative Example 8)

A biaxially stretched optical film having no easy adhesive layer by performing the same operation as Comparative Example 2 except for using the longitudinally stretched film F43 prepared in Production Example 18 instead of the longitudinally stretched film F2 ( F46) and an optical film (F47) having a hard coat layer. The haze of the obtained films (F46) and (F47) was 0.2% and 0.2%, respectively, and the adhesiveness of the hard-coat layer was 30.

The evaluation results of the optical films prepared in the Examples and Comparative Examples are shown in Tables 1 and 2, respectively. Moreover, the adhesiveness of a hard coat layer should just be 50% or more, and it is preferable that it is 90% or more.

The optical film of the present invention is suitable for use in various protective films such as polarizer protective films used in image display devices such as LCDs, retardation films, and polarizing films.

1a ~ 1d ... optical film of invention
2 ... acrylic resin film
3 ... easy adhesive layer (a)
4 ... functional coating layer
5 ... easy adhesive layer (b)
6 ... adhesive layer
7 ... other members
8 ... polarizer
9 ... adhesive layer

Claims (17)

An acrylic resin film composed of an acrylic resin (A) containing a (meth) acrylic polymer having a ring structure in a main chain, and an easy adhesive layer (a) containing a polyester-acrylic composite resin (B); a) does not contain a sugar alcohol and / or a sugar alcohol derivative, the polyester-acrylic composite resin (B) has an epoxy group and a carboxyl group, and the easy adhesive layer (a) contains fine particles, and the average of the fine particles 1 Difference particle diameter is 110-200 nm, particle size distribution of the fine particles is 1.0-1.4,
The easy adhesive layer (a) is formed on one main surface of the acrylic resin film, characterized in that it has an optical film having a functional coating layer formed on the surface of the easy adhesive layer (a) facing the surface of the acrylic resin film side Polarizer protective film. delete delete delete delete delete The polarizer protective film according to claim 1, wherein an easy adhesive layer (b) is formed on a main surface opposite to a surface on which the easy adhesive layer (a) is formed. The polarizer protective film of claim 7, wherein the easy adhesive layer (b) is a urethane resin layer. The polarizer protective film according to claim 7, wherein an adhesive layer is formed on a surface of the easy adhesive layer (b) that faces the acrylic resin film side. delete The polarizer protection according to claim 1, wherein the ring structure is at least one member selected from the group consisting of maleic anhydride structure, N-substituted maleimide structure, glutaric anhydride structure, glutarimide structure and lactone ring structure. film. The polarizer protective film according to claim 1, wherein the optical transmittance at 380 nm of the optical film is 30% or less. The polarizer protective film according to claim 12, wherein the acrylic resin film of the optical film contains a ultraviolet absorber having a molecular weight of 600 or more. delete The polarizing plate which has a polarizer protective film as described in any one of Claims 1, 7-9, and 11-13. The polarizing plate of Claim 15 is provided, The image display apparatus characterized by the above-mentioned.
The polarizer protective film of claim 1, wherein the functional coating layer is a hard coat layer.

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