KR20160147856A - Methacrylic resin composition, method for producing same, molded body, film, and polarizing plate - Google Patents

Abstract

A methacrylic resin composition having high transparency, a small retardation in the thickness direction, and easy stretching. The methacrylic resin composition of the present invention comprises a methacrylic resin having a structural unit derived from methyl methacrylate of 80 mass% or more and a weight average molecular weight of 200000 or less, and a methacrylic resin having a viscosity average molecular weight of 1000 or more and 32000 or less, A polycarbonate resin having a content of 1 to 4 parts by mass relative to 100 parts by mass of a methacrylic resin, and a polymer processing aid having an average degree of polymerization of 3,000 to 40,000 and having a content of 0.3 to 6 parts by mass with respect to 100 parts by mass of the methacrylic resin , And the total amount of the methacrylic resin and the polycarbonate resin contained in the methacrylic resin composition is 80 mass% or more.

Description

Technical Field [0001] The present invention relates to a methacrylic resin composition, a method for producing the same, a molded article, a film, and a polarizing plate,

The present invention relates to a methacrylic resin composition comprising a methacrylic resin and a polycarbonate resin. The present invention also relates to a film made of the methacrylic resin composition, a molded product thereof, and a polarizing plate comprising the film.

Various resin films are used for the liquid crystal display device. Triacetyl cellulose is mainly used as a polarizer protective film. Since the film made of triacetyl cellulose has a high moisture permeability, there is a tendency that the quality of the polarizer deteriorates as the film becomes thinner. The improvement of the polarizer protective film has been a problem in the thinning of the liquid crystal display device.

Thus, a methacrylic resin has been studied as a material for a new polarizer protective film. It is known that a film made of a methacrylic resin is subjected to stretching treatment to increase toughness (see Patent Document 1). However, if a conventional methacrylic resin film is stretched, the phase difference becomes large. For example, in the IPS liquid crystal system, the quality of the screen is degraded.

It is known that by adding a resin such as a polycarbonate resin to a methacrylic resin, it becomes easy to obtain a film having a small retardation (Patent Documents 2 to 5). However, since these methacrylic resin compositions contain a polycarbonate resin having a low molecular weight to ensure transparency, the extensibility is not sufficient. Specifically, when the film is stretched to a thin film, it tends to be easily cracked. Further, in order to increase the strength of the film after stretching, the film tends to be broken when stretching at a lower temperature. In order to improve the heat resistance of the methacrylic resin composition, a methacrylic resin having a high syndiotacticity (rr) in triplet is generally narrower in molecular weight distribution, and is more flexible than a methacrylic resin composition using a conventional methacrylic resin It was not enough.

Japanese Patent Publication No. 57-32942 Japanese Unexamined Patent Publication No. 5-32846 Japanese Laid-Open Patent Publication No. 2012-514759 Japanese Laid-Open Patent Publication No. 2013-148655 Japanese Laid-Open Patent Publication No. 2014-51649

An object of the present invention is to provide a methacrylic resin composition which is high in transparency, has a small retardation in the thickness direction, and is easy to stretch. Another object of the present invention is to provide a film made of a methacrylic resin composition having uniform thickness, excellent surface smoothness, high productivity, and high strength.

Means for Solving the Problems As a result of extensive studies to achieve the above object, the present inventors have completed the present invention including the following aspects.

[1] A methacrylic resin composition containing a methacrylic resin, a polycarbonate resin and a polymer processing aid,

The methacrylic resin preferably has a structural unit derived from methyl methacrylate of 80 mass% or more, a weight average molecular weight of 200,000 or less,

Wherein the polycarbonate resin has a viscosity average molecular weight of 1000 or more and 32000 or less and the content of the polycarbonate resin relative to 100 parts by mass of the methacrylic resin is 1 part by mass or more and 4 parts by mass or less,

Wherein the polymer processing aid has an average degree of polymerization of 3,000 or more and 40,000 or less and the content of the polymer processing aid in relation to 100 parts by mass of the methacrylic resin is 0.3 parts by mass or more and 6 parts by mass or less,

Wherein the total amount of the methacrylic resin and the polycarbonate resin contained in the methacrylic resin composition is 80 mass% or more.

Wherein the methacrylic resin has a syndiotacticity (rr) of at least 50%, a weight average molecular weight of 80,000 to 200,000, and a content of a structural unit derived from methyl methacrylate of 92 By mass or more and 100% by mass or less, based on the total mass of the methacrylic resin composition.

[3] The methacrylic resin composition according to [1] or [2], wherein the methacrylic resin has a syndiotacticity (rr) of 58% or more and 85% or less.

[4] The methacrylic resin composition according to any one of [1] to [3], wherein the content of the structural unit derived from the methacrylic acid methyl group in the methacrylic resin is 99% by mass or more.

[5] The methacrylic resin composition according to any one of [1] to [4], wherein the polycarbonate resin has a viscosity average molecular weight of 5000 or more and 18000 or less.

[6] The methacrylic resin composition according to any one of [1] to [5], wherein the methacrylic resin composition has a weight average molecular weight of 70,000 to 200,000.

[7] The methacrylic resin composition according to any one of [1] to [6], wherein the methacrylic resin composition has a molecular weight distribution of 1.2 to 2.5.

[8] A molded article comprising the methacrylic resin composition according to any one of [1] to [7].

[9] A film comprising the methacrylic resin composition according to any one of [1] to [7].

[10] A film according to [9], wherein the thickness is 10 to 50 μm.

[11] A film according to [9] or [10], wherein the film is biaxially stretched at an area ratio of 1.5 to 8 times.

[12] A film according to any one of [9] to [11], which is used as a polarizer protective film.

[13] A polarizing plate in which at least one film described in [12] is laminated.

[14] 100 parts by mass of a methacrylic resin having a structural unit derived from methyl methacrylate of 80% by mass or more and a weight average molecular weight of 200,000 or less and 100 parts by mass of a polycarbonate resin 1 having a viscosity average molecular weight of 1000 or more and 32000 or less Not less than 4 parts by mass and not less than 3,000 parts by mass and not more than 40,000 parts by mass of at least three components selected from the group consisting of not less than 0.3 parts by mass and not more than 6 parts by mass of a polymer processing aid.

According to the present invention, it is possible to provide a methacrylic resin composition having high transparency, a small retardation in the thickness direction, and easy stretching. In addition, it exerts an excellent effect that a film made of a methacrylic resin composition having uniform thickness, excellent surface smoothness, high productivity, and high strength can be provided.

1 is a cross-sectional view showing an example of a polarizing plate according to an embodiment of the present invention.

The methacrylic resin composition of the present invention contains a methacrylic resin, a polycarbonate resin and a polymer processing aid. The film of the present invention is a film made of the methacrylic resin composition.

The content of the structural unit derived from methyl methacrylate in the methacrylic resin used in the present invention is 80 mass% or more based on the mass of the methacrylic resin, preferably 92 mass% More preferably 95% by mass or more, further preferably 97% by mass or more, particularly preferably 99% by mass or more, and most preferably 100% by mass.

The methacrylic resin used in the present invention may contain structural units other than the structural units derived from methyl methacrylate, and examples thereof include ethyl methacrylate, cyclohexyl methacrylate, t-butyl methacrylate , Methacrylic acid other than methyl methacrylate such as 2-isobornyl methacrylate, 8-tricyclo [5.2.1.0 ^2,6 ] decanyl methacrylate and 4-t-butylcyclohexyl methacrylate Esters; Acrylic acid alkyl esters such as methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate and 2-ethylhexyl acrylate; Acrylic acid aryl esters such as phenyl acrylate; Acrylic acid cycloalkyl esters such as cyclohexyl acrylate and norbornenyl acrylate; Acrylamide; Methacrylamide; Acrylonitrile; Methacrylonitrile; And the like can be given as a structural unit derived from a vinyl-based monomer having only one polymerizable carbon-carbon double bond in one molecule. The structural unit other than the structural unit derived from methyl methacrylate is preferably 8 mass% or less, more preferably 5 mass% or less, further preferably 3 mass% or less, particularly preferably 1 mass% or less, Most preferably 0 mass%.

The methacrylic resin to be used in the present invention is preferably 50%, more preferably 55%, further preferably 58%, further preferably 50%, more preferably 50% , More preferably 59%, and most preferably 60%. The methacrylic resin preferably has an upper limit of syndiotacticity (rr) of 3 symbols in terms of film formability, preferably 99%, more preferably 85%, even more preferably 77%, still more preferably 70 %, Still more preferably 65%, most preferably 64%. Since the methacrylic resin having the syndiotacticity has a narrow molecular weight distribution and the stretchability is not sufficient, the addition of the polymer processing aid exhibits a more effective effect.

The syndiotacticity rr of the triplet display (hereinafter sometimes simply referred to as " syndiotacticity (rr) ") is a value obtained by dividing the number of repeating three structural units (triad) It is the ratio that the chain (two consecutive, diad) is all three (it is denoted rr). In the chain of the structural units (two consecutive diad) in the polymer molecule, the same configuration is referred to as meso, and the opposite configuration is referred to as racemo, and m and r are respectively denoted.

The syndiotacticity (rr) (%) of the methacrylic resin was determined by measuring the ¹ H-NMR spectrum of the deuterated chloroform at 30 ° C from the spectrum and calculating the syndiotacticity of the methacrylic resin in the range of 0.6 to 0.95 ppm The area (X) and the area (Y) in the region of 0.6 to 1.35 ppm can be calculated and can be calculated by the formula: (X / Y) x 100.

The methacrylic resin used in the present invention has a weight average molecular weight (hereinafter sometimes referred to as "Mw") of 200,000 or less, preferably 80,000 to 200,000, more preferably 85,000 to 160,000, and even more preferably 90000 ~ 120000. When the Mw is not less than 80000 and the syndiotacticity (rr) is not less than 50%, the resulting film has high strength, is not easily cracked, and is easily stretched. Therefore, the film can be made thinner. Further, when the Mw is 200,000 or less, the molding processability of the methacrylic resin becomes high, so that the obtained film tends to have a uniform thickness and excellent surface smoothness.

The methacrylic resin used in the present invention has a ratio (Mw / Mn: hereinafter sometimes referred to as "molecular weight distribution") of Mw to number average molecular weight Preferably 1.2 to 2.0, and more preferably 1.3 to 1.7. Since the molecular weight distribution is 1.2 or more, the flowability of the methacrylic resin is improved, and the obtained film tends to have excellent surface smoothness. A film obtained by a molecular weight distribution of 2.0 or less tends to have excellent impact resistance and toughness. Mw and Mn are values obtained by converting the chromatogram measured by gel permeation chromatography (GPC) into the molecular weight of standard polystyrene.

The methacrylic resin used in the present invention preferably has a melt flow rate of 0.1 to 5 g / 10 min, more preferably 0.5 to 4 g / 10 min, at 230 ° C under a load of 3.8 kg in accordance with JIS K7210, 10 min, and most preferably 1.0 to 3 g / 10 min.

The glass transition temperature of the methacrylic resin used in the present invention is preferably at least 110 ° C, more preferably at least 118 ° C, more preferably at least 120 ° C, even more preferably at least 123 ° C, 124 ° C or higher. The upper limit of the glass transition temperature of the methacrylic resin is usually 140 占 폚, preferably 130 占 폚. The glass transition temperature can be controlled by adjusting the molecular weight or syndiotacticity (rr). When the glass transition temperature is within this range, heat shrinkage or the like of the obtained film is hardly deformed. The glass transition temperature is the midpoint glass transition temperature measured by the method described in the Examples.

The method for producing the methacrylic resin is not particularly limited. For example, by adjusting the polymerization temperature, the polymerization time, the kind and amount of the chain transfer agent, and the kind and amount of the polymerization initiator in a known polymerization method such as a radical polymerization method and an anion polymerization method, (Rr) and the like satisfying a desired range can be produced.

For example, in the case of the radical polymerization method, the polymerization temperature is preferably 80 占 폚 or lower, more preferably 70 占 폚 or lower, and still more preferably 60 占 폚 or lower. By adjusting the temperature in this manner, it is easy to increase the syndiotacticity rr.

In the case of the anion polymerization method, it is preferable to use alkyllithium such as n-butyllithium, sec-butyllithium, isobutyllithium, tert-butyllithium as a polymerization initiator. From the viewpoint of productivity, it is preferable to coexist the organoaluminum compound. As the organic aluminum,

AlR ¹ R ² R ³

(Wherein R ¹ , R ² and R ³ each independently represent an alkyl group which may have a substituent, a cycloalkyl group which may have a substituent, an aryl group which may have a substituent, an aralkyl group which may have a substituent, An aryloxy group which may have a substituent, or an N, N-2-substituted amino group, R ² and R ³ may be an arylenedioxy group which may have a substituent and are each bonded to each other.

And the like. Specific examples thereof include isobutylbis (2,6-di-tert-butyl-4-methylphenoxy) aluminum, isobutylbis (2,6- -Methylenebis (4-methyl-6-tert-butylphenoxy)] aluminum.

In the anionic polymerization method, an ether or a nitrogen-containing compound may be coexisted to control the polymerization reaction.

When the methacrylic resin is produced by an anionic polymerization method, the amount of the polymerization initiator is preferably less than the amount of the polymerization initiator in the course of the polymerization reaction, more preferably 1 mol% to 50 mol% Is added in an amount of from 2 mol% to 20 mol%, and more preferably from 5 mol% to 10 mol%, based on the amount of the polymerization initiator added first in the course of the polymerization reaction, The weight average molecular weight can be adjusted by further adding a polymerization initiator in an amount of 50 mol%, more preferably 2 mol% to 20 mol%, and still more preferably 5 mol% to 10 mol%.

As a second method for obtaining a methacrylic resin having desired properties such as weight average molecular weight and syndiotacticity (rr), a methacrylic resin which does not satisfy desired characteristics is mixed in a part, or methacrylic A method of obtaining a methacrylic resin having desired properties (properties such as weight average molecular weight, syndiotacticity (rr)) by appropriately mixing the resins. This method facilitates process control. The mixing of the plural kinds of methacrylic resins can be carried out by a known method, for example, a melt kneading apparatus such as a kneader rudder, an extruder, a mixing roll, and a Banbury mixer. The temperature at the time of kneading can be appropriately adjusted according to the melting temperature of the methacrylic resin to be used, and is usually 150 to 300 占 폚.

A third production method for obtaining a methacrylic resin having desired properties is to polymerize a monomer in the presence of a methacrylic resin deviating from a desired characteristic range to obtain a desired weight average molecular weight and syndiotacticity (rr) Of the methacrylic resin. Such polymerization can be carried out in the same manner as in the above-mentioned radical polymerization method or anion polymerization method. According to the third production method, the thermal history to be applied to the methacrylic resin is shortened as compared with the second production method, so that thermal decomposition of the methacrylic resin is suppressed, and a film having little coloration and foreign matter can be easily obtained.

Among the above methacrylic resin production methods, there are a method of producing a methacrylic resin whose characteristics satisfy the desired range by an anionic polymerization method from the viewpoint of easily producing a methacrylic resin having high transparency; A method of producing a methacrylic resin having characteristics satisfying a specified range by mixing a methacrylic resin produced by an anionic polymerization method with a methacrylic resin produced by radical polymerization; And methacrylic resin produced by an anionic polymerization method and methacrylic resin produced by another anionic polymerization method are mixed with each other to produce a methacrylic resin satisfying a desired range of properties, Methacrylic resin prepared by radical polymerization and a methacrylic resin produced by radical polymerization are mixed with each other to produce a methacrylic resin having characteristics satisfying a desired range.

The polycarbonate resin used in the present invention is a polymer obtained by a reaction between a polyfunctional hydroxy compound and a carbonic acid ester-forming compound. The polycarbonate resin is preferably an aromatic polycarbonate resin from the viewpoint of compatibility with the methacrylic resin and transparency of the resulting film.

The polycarbonate resin used in the present invention has a viscosity average molecular weight (hereinafter sometimes referred to as " Mv ") of 1000 or more, preferably 3000 or more, from the viewpoint that the polycarbonate is difficult to be bleed out from the resulting methacrylic resin composition More preferably 5000 or more, and further preferably 10000 or more. From the viewpoint of compatibility with the methacrylic resin, the viscosity average molecular weight is 32000 or less, preferably 22000 or less, more preferably 18000 or less, further preferably 17000 or less. The higher the syndiotacticity (rr) of the methacrylic resin to be used, the higher the compatibility with the polycarbonate resin and the higher viscosity average molecular weight of the polycarbonate resin can be used. When such a polycarbonate having a relatively small viscosity average molecular weight is added, the extensibility is lowered, so that the addition of the polymer processing aid exhibits more effects.

The viscosity-average molecular weight (Mv) of the polycarbonate resin is, Canon -pentanoic schedule viscometer and using a de viscometer by Ube polycarbonate and the resin 0.5 g Fig η _sp boiling point of the solution, dissolved in 100 ㎖ methylene chloride measured at 20 ℃ , Can be calculated from the intrinsic viscosity [eta] of a methylene chloride solution at 20 [deg.] C as a value satisfying the following Schnell equation.

η _sp / c = [η] + 0.45 × [η] ² c

([Eta] is an intrinsic viscosity, c = 0.5 in the above condition)

[?] = 1.23 10 ^-4 Mv ^0.83

The MVR (melt volume flow rate) value of the polycarbonate resin used in the present invention at 300 캜 and 1.2 kg is preferably 1.0 cm 3/10 min or more, more preferably 10 cm 3 / More preferably 10 minutes or more, still more preferably 25 cm3 / 10 minutes or more, and particularly preferably 33 cm3 / 10 minutes or more. From the viewpoint that the polycarbonate is hardly bleed out from the methacrylic resin composition to be obtained, it is preferably 2 x 10 ⁷ cm 3/10 min or less, more preferably 1 x 10 ⁵ cm 3/10 min or less, and further preferably 10000 cm 3 / More preferably 390 cm < 3 > / 10 minutes or less.

In the polycarbonate resin used in the present invention, the weight average molecular weight (Mw) obtained by converting the chromatogram measured by gel permeation chromatography (GPC) into the molecular weight of standard polystyrene is from the obtained methacrylic resin composition to the polycarbonate resin The Mw is preferably 1300 g / mol or more, more preferably 4700 g / mol or more, still more preferably 8500 g / mol or more, and particularly preferably 19200 g / mol or more from the viewpoint of difficulty in bleeding out. Further, from the viewpoint of compatibility with a methacrylic resin, it is preferably 75000 g / mole or less, more preferably 48300 g / mole or less, still more preferably 38200 g / mole or less, particularly preferably 35700 g / mole or less.

The viscosity average molecular weight, MVR value or weight average molecular weight of the polycarbonate resin can be adjusted by adjusting the amount of the terminal terminator and the branching agent.

The glass transition temperature of the polycarbonate resin used in the present invention is preferably 110 占 폚 or higher, more preferably 125 占 폚 or higher, and even more preferably 140 占 폚 or higher. The upper limit of the glass transition temperature of the polycarbonate resin is usually 180 占 폚.

The production method of the polycarbonate resin is not particularly limited. Examples thereof include a phosgene method (interfacial polymerization method) and a melt polymerization method (ester exchange method). The aromatic polycarbonate resin preferably used in the present invention may be one obtained by subjecting a polycarbonate resin raw material produced by the melt polymerization method to a treatment for adjusting the terminal hydroxy group amount.

Examples of the polyfunctional hydroxy compound as a raw material for producing the polycarbonate resin include 4,4'-hydroxybiphenyls which may have a substituent; Bis (hydroxyphenyl) alkanes which may have a substituent; Bis (4-hydroxyphenyl) ethers which may have a substituent; Bis (4-hydroxyphenyl) sulfide which may have a substituent; Bis (4-hydroxyphenyl) sulfoxide which may have a substituent; Bis (4-hydroxyphenyl) sulfone which may have a substituent; Bis (4-hydroxyphenyl) ketones which may have a substituent; Bis (hydroxyphenyl) fluorenes which may have a substituent; Dihydroxy-p-terphenyl which may have a substituent; Dihydroxy-p-quaterphenyl which may have a substituent; Bis (hydroxyphenyl) pyrazine which may have a substituent; Bis (hydroxyphenyl) mannant which may have a substituent; Bis [2- (4-hydroxyphenyl) -2-propyl] benzenes which may have a substituent; Dihydroxynaphthalenes which may have a substituent; Dihydroxybenzenes which may have a substituent; Polysiloxanes which may have a substituent; Dihydro perfluoroalkane which may have a substituent, and the like.

Among these multifunctional hydroxy compounds, preferred are 2,2-bis (4-hydroxyphenyl) propane, 1,1-bis (4-hydroxyphenyl) cyclohexane, bis Bis (4-hydroxyphenyl) -1-phenylethane, 2,2-bis (4-hydroxy-3-methylphenyl) propane, 2,2- Propane, 4,4'-dihydroxybiphenyl, bis (4-hydroxyphenyl) sulfone, 2,2-bis (3,5-dibromo- (4-hydroxyphenyl) pentane, 9,9-bis (4-hydroxy-3-methylphenyl) fluorene, bis Bis [3- (2-hydroxyphenyl) propyl] poly (2-hydroxyphenyl) propane, 1,1,1,3,3,3-hexafluoropropane, Dimethyl siloxane, resorcin, and 2,7-dihydroxynaphthalene are preferable, and 2,2-bis (4-hydroxyphenyl) propane is particularly preferable.

Examples of the carbonate ester-forming compound include various dihalogenated carbonyls such as phosgene, haloformates such as chloroformate, and carbonate ester compounds such as bisaryl carbonate. The amount of the carbonic ester-forming compound may be appropriately adjusted in consideration of the stoichiometric ratio (equivalence) of the reaction.

The reaction is usually carried out in a solvent in the presence of an acid binder. Examples of the acid coupling agent include alkali metal hydroxides such as sodium hydroxide, potassium hydroxide, lithium hydroxide and cesium hydroxide, alkali metal carbonates such as sodium carbonate and potassium carbonate, and organic bases such as trimethylamine, triethylamine, tributylamine, N, Tertiary amines such as trimethylbenzylammonium chloride, triethylbenzylammonium chloride, tributylbenzylammonium chloride, trioctylmethylammonium chloride, tetrabutylammonium chloride and tetrabutylammonium bromide, and the like, such as trimethylbenzylammonium chloride, cyclohexylamine, pyridine and dimethyl aniline; Quaternary phosphonium salts such as ammonium salts, tetrabutylphosphonium chloride and tetrabutylphosphonium bromide. In addition, a small amount of an antioxidant such as sodium sulfite or hydrosulfide may be added to the reaction system as desired. The amount of the acid binder may be appropriately adjusted in consideration of the stoichiometric ratio (equivalence) of the reaction. Specifically, an acid binding agent may be used in an amount of 1 equivalent or more, preferably 1 to 5 equivalents, per 1 mole of the hydroxyl group of the starting polyfunctional hydroxy compound.

In the reaction, a known terminal terminator or branching agent can be used. Examples of the terminal terminating agent include p-tert-butylphenol, p-phenylphenol, p-cumylphenol, p-perfluorononylphenol, p- (perfluorononylphenyl) phenol, p- (perfluorohexylphenyl ) Phenol, p-tert-perfluorobutylphenol, 1- (P-hydroxybenzyl) perfluorodecane, p- [2- (1H, 1H-perfluorotridodecyloxy) , 3,3,3-hexafluoropropyl] phenol, 3,5-bis (perfluorohexyloxycarbonyl) phenol, p-hydroxybenzoic acid perfluorododecyl, p- (1H, 2, 2H, 9H-perfluorononanic acid, and 1,1,1,3,3,3-tetrafluoro-2-propanol.

Branching agents include, but are not limited to, fluoroglycine, pyrogallol, 4,6-dimethyl-2,4,6-tris (4-hydroxyphenyl) -2-heptene, 2,6- Tris (4-hydroxyphenyl) heptane, 1,3,5-tris (2-hydroxyphenyl) benzene, 1 Tris (4-hydroxyphenyl) benzene, 1,1,1-tris (4-hydroxyphenyl) ethane, tris (4-hydroxyphenyl) phenylmethane, 2,2- Bis (4-hydroxyphenyl) -2-propyl] phenol, 2,6-bis (2-hydroxy- 2- (2,4-dihydroxyphenyl) propane, tetrakis (4-hydroxyphenyl) methane, tetrakis [4- (3-methyl-4-hydroxyphenyl) -2-oxo (2-hydroxyphenyl) isopropoxy) phenoxy] methane, 2,4-dihydroxybenzoic acid, -2,3-dihydroindole, 3,3-bis (4-hydroxy Reel), and the oxy-indole, 5-chloroisatin satin, satin dikeulroroyi 5,7, 5-bromo feeders such as satin.

The polycarbonate resin may contain, in addition to a polycarbonate unit, a unit having a polyester, polyurethane, polyether or polysiloxane structure or the like.

Polymer processing aids are substances that contain high molecular weight components. (Network) between the polymers is generated between the polymer processing aid and the resin material, and the point of intersection functions as a pseudo crosslinking point. Therefore, when the polymer processing aid is added, the resin composition can be uniformly stretched as in the case of deforming the rubber. In the case of a resin material to which a polymer processing aid is not added, since there is no pseudo-crosslinking point, for example, if a thinner portion is present in a film before stretching, stress is concentrated on the portion and stretched locally to break Sometimes a problem arises.

The polymer processing aid used in the present invention is a polymer compound having an average degree of polymerization of 3,000 to 40,000, preferably 60% by mass or more of methyl methacrylate units and 40% by mass or less of vinyl monomer units copolymerizable therewith . The average polymerization degree is preferably 6,000 to 30,000, more preferably 10,000 to 25,000. Examples of the vinyl monomer copolymerizable with methyl methacrylate include methacrylic acid esters such as ethyl methacrylate, butyl methacrylate and cyclohexyl methacrylate, ethyl acrylate, methyl acrylate, butyl acrylate, cyclohexyl acrylate and the like Aromatic vinyl compounds such as acrylic acid ester, styrene, p-methylstyrene and o-methylstyrene, maleimide compounds such as N-propylmaleimide, N-cyclohexylmaleimide and No-chlorophenylmaleimide, Propyleneglycol dimethacrylate, hexanediol dimethacrylate, ethylene glycol diacrylate, propylene glycol diacrylate, triethylene glycol diacrylate, allyl methacrylate, tri And polyfunctional monomers such as allyl isocyanurate. Examples of such a polymer processing aid include Metablen series manufactured by Mitsubishi Rayon Co., Ltd., Parodoid series manufactured by Dow Chemical Co., Ltd. or Kureha Co., In addition, the average degree of polymerization of the polymer processing aid can be determined by measuring the degree of polymerization in terms of PMMA using an automatic dilution type capillary viscometer (Ube Dept.) and measuring chloroform as a solvent at 20 ° C.

The polymerization method for producing the polymer processing aid is not particularly limited, but it is preferable to use emulsion polymerization. Examples of the emulsifier that can be used for the emulsion polymerization include dialkylsulfosuccinates such as sodium dioctylsulfosuccinate and sodium dilaurylsulfosuccinate which are anionic emulsifiers, alkylbenzenesulfonic acid salts such as sodium dodecylbenzenesulfonate, Polyoxyethylene nonylphenyl ether sulfates such as polyoxyethylene nonylphenyl ether sulfates such as polyoxyethylene nonylphenyl ether sulfates which are nonionic and anionic emulsifiers such as polyoxyethylene alkyl ethers and polyoxyethylene nonylphenyl ethers which are nonionic emulsifiers, Polyoxyethylene alkyl ether sulfate such as sodium polyoxyethylene alkyl ether sulfate and alkyl ether carboxylate such as sodium polyoxyethylene tridecyl ether acetate can be used.

When the pH of the polymerization system is changed to the alkaline side depending on the kind of the emulsifier to be used, a suitable pH adjuster may be used to prevent hydrolysis of the alkyl methacrylate ester and the alkyl acrylate ester. Examples of the pH adjuster to be used include boric acid-potassium chloride-potassium hydroxide, potassium dihydrogenphosphate-disodium hydrogenphosphate, boric acid-potassium chloride-potassium carbonate, citric acid-potassium hydrogen citrate, potassium dihydrogenphosphate-boric acid, disodium hydrogenphosphate- Can be used.

As the polymerization initiator, a water-soluble initiator or an oil-soluble initiator may be used alone or in a redox system. Examples of the water-soluble initiator include an inorganic initiator such as a common persulfate, or a sulfoxide, It may be used as a redox type initiator by combination with a thiosulfate or the like.

Examples of the oil-soluble initiator include organic peroxides such as tert-butyl hydroperoxide, cumene hydroperoxide, benzoyl peroxide, and lauroyl peroxide, and azo compounds, or in combination with sodium formaldehyde sulfoxylate May be used as a redox-type initiator. However, the present invention is not limited to these specific examples.

The average polymerization degree of the polymer processing aid can be arbitrarily adjusted by a chain transfer agent such as n-octyl mercaptan, tert-dodecyl mercaptan, or polymerization conditions.

The average degree of polymerization of the polymer processing aid of the present invention is in the range of 3,000 to 40,000. When the average degree of polymerization of the polymer processing aid is less than 3,000, improvement in film forming property when the methacrylic resin composition of the present invention is used as a film may not be confirmed, and improvement in improvement in drawability may not be sufficiently confirmed when stretched . On the other hand, when the average degree of polymerization of the polymer processing aid exceeds 40,000, the transparency is lowered or the melt tension is excessively high, and both ends of the melted curtain tend to be torn at the time of film formation. The blending amount of the polymer processing aid is 0.3 to 6 parts by mass, preferably 0.5 to 3 parts by mass based on 100 parts by mass of the methacrylic resin. If the blending amount of the polymer processing aid is less than 0.3 part by mass, a satisfactory improvement effect of film formability and stretchability of the methacrylic resin composition will not be exhibited. On the other hand, when the blending amount of the polymer processing aid exceeds 6 parts by mass, the glass transition temperature of the methacrylic resin composition is lowered, the transparency is lowered, and the melt tension is excessively high, and both ends of the melted curtain tend to be torn at the time of film formation .

The content of the polycarbonate resin contained in the methacrylic resin composition of the present invention is 1 part by mass or more and 4 parts by mass or less, more preferably 2 parts by mass or more and 3 parts by mass or less based on 100 parts by mass of the methacrylic resin .

The total amount of the methacrylic resin and the polycarbonate resin contained in the methacrylic resin composition of the present invention is 80 mass% or more, preferably 90 mass% or more, more preferably 94 mass% or more, further preferably 96 mass% or more to be. With respect to the upper limit of such a quantity, there is no particular limitation so long as the polymer processing aid can be contained in the methacrylic resin composition of the present invention within the range in which the effect of the present invention can be obtained.

The methacrylic resin composition of the present invention may contain a filler as necessary insofar as the effect of the present invention is not impaired. Examples of the filler include calcium carbonate, talc, carbon black, titanium oxide, silica, clay, barium sulfate, magnesium carbonate and the like. The amount of the filler that can be contained in the methacrylic resin composition of the present invention is preferably 3 mass% or less, more preferably 1.5 mass% or less.

The methacrylic resin composition of the present invention may contain other polymers within the range not hindering the effect of the present invention. Other polymers include polyolefin resins such as polyethylene, polypropylene, polybutene-1, poly-4-methylpentene-1 and polynorbornene; Ethylenic ionomers; Styrene resins such as polystyrene, styrene-maleic anhydride copolymer, high impact polystyrene, AS resin, ABS resin, AES resin, AAS resin, ACS resin and MBS resin; Methyl methacrylate-styrene copolymer; Polyester resins such as polyethylene terephthalate and polybutylene terephthalate; Nylon 6, nylon 66, and polyamide elastomers; Polyvinyl chloride, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, ethylene-vinyl alcohol copolymer, polyacetal, polyvinylidene fluoride, polyurethane, modified polyphenylene ether, polyphenylene sulfide, phenoxy resin, silicone modified resin; Acrylic rubber, acrylic thermoplastic elastomer, silicone rubber; Styrene-based thermoplastic elastomers such as SEPS, SEBS and SIS; And olefin rubbers such as IR, EPR and EPDM. The amount of other polymer that can be contained in the methacrylic resin composition used in the present invention is preferably 10 mass% or less, more preferably 5 mass% or less, and most preferably 0 mass%.

The methacrylic resin composition of the present invention may contain an antioxidant, a thermal deterioration inhibitor, an ultraviolet absorber, a light stabilizer, a lubricant, a release agent, an antistatic agent, a flame retardant, a salt pigment, , A gloss removing agent, an impact resistance modifier, a phosphor, and the like.

The antioxidant is effective in preventing deterioration of the oxidation of the resin in the presence of oxygen. Examples thereof include phosphorus antioxidants, hindered phenol antioxidants, thioether antioxidants and the like. Of these, a phosphorus-based antioxidant and a hindered phenol-based antioxidant are preferable from the viewpoint of an effect of preventing deterioration of optical characteristics due to coloring, and a phosphorus-based antioxidant and a hindered phenol-based antioxidant are more preferably used in combination.

When the phosphorus-based antioxidant and the hindered phenol-based antioxidant are used in combination, the phosphorus-based antioxidant / hindered phenol-based antioxidant is preferably used in a mass ratio of 0.2: 1 to 2: 1, more preferably 0.5: 1 to 1/1 It is more preferable to use it.

Examples of the phosphorus antioxidant include 2,2-methylenebis (4,6-di-tert-butylphenyl) octyl phosphite (trade name: Adekastab HP-10 manufactured by ADEKA), tris (2,4- tert-butylphenyl) phosphite (trade name: IRGAFOS168 manufactured by BASF), 3,9-bis (2,6-di-tert- butyl-4-methylphenoxy) -2,4,8,10- -3,9-diphosphaspiro [5.5] undecane (trade name: Adecastab PEP-36, manufactured by ADEKA).

Examples of the hindered phenol antioxidant include pentaerythrityl-tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] (trade name IRGANOX1010, Decyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate (trade name IRGANOX1076, manufactured by BASF).

As the thermal deterioration preventing agent, thermal degradation of the resin can be prevented by capturing the polymer radical generated when exposed to high temperature under substantially anaerobic conditions.

Examples of the thermal deterioration preventing agent include 2-tert-butyl-6- (3'-tert-butyl-5'-methyl-hydroxybenzyl) -4-methylphenylacrylate (Sumitomo Chemical Co., , 4-di-tert-amyl-6- (3 ', 5'-di-tert-amyl-2'-hydroxy- alpha -methylbenzyl) phenyl acrylate (Sumilizer GS, desirable.

The ultraviolet absorber is a compound having an ability to absorb ultraviolet rays, and is known to have a function of mainly converting light energy into heat energy.

Examples of the ultraviolet absorber include benzophenones, benzotriazoles, triazines, benzoates, salicylates, cyanoacrylates, anilides oxalic acid, malonic acid esters and formamidines. Among them, benzotriazoles, triazines, or ultraviolet absorbers having a maximum molar extinction coefficient ε _max of 100 dm 3 · mol ^-1 cm ^-1 or less at a wavelength of 380 to 450 nm are preferable.

Since benzotriazoles have a high effect of suppressing deterioration of optical properties such as coloration caused by ultraviolet ray irradiation (illumination), they are preferable as ultraviolet absorbers for use in application of the film of the present invention to optical use. Examples of benzotriazoles include 2- (2H-benzotriazol-2-yl) -4- (1,1,3,3-tetramethylbutyl) phenol (trade name: TINUVIN329, Methyl-1-phenylethyl) phenol (trade name: TINUVIN234, manufactured by BASF), 2,2'-methylenebis [6- (2H-benzotriazole (5-octylthio-2H-benzotriazol-2-yl) -6-tert-butyl-4- Methylphenol and the like are preferable.

In addition, the ultraviolet absorber having the maximum value? _Max of the molar extinction coefficient at a wavelength of 380 to 450 nm of 1,200 dm 3 ㏖ ^-1 cm ^-1 or less can suppress discoloration of the resulting film. Examples of such an ultraviolet absorber include 2-ethyl-2'-ethoxy-oxalanilide (manufactured by Clariant Japan Co., Ltd., trade name: SUNDY Boa VSU).

Of these ultraviolet absorbers, benzotriazoles are preferably used from the viewpoint that the resin deterioration due to ultraviolet radiation is inhibited.

In the case where a wavelength near 380 nm is desirably absorbed, a triazine ultraviolet absorber is preferably used. Examples of such ultraviolet absorbers include 2,4,6-tris (2-hydroxy-4-hexyloxy-3-methylphenyl) -1,3,5-triazine (LA- Hydroxyphenyltriazine type ultraviolet absorber (TINUVIN477 or TINUVIN460, manufactured by BASF), 2,4-diphenyl-6- (2-hydroxy-4-hexyloxyphenyl) -1,3,5-triazine And the like.

The maximum value? _Max of the molar extinction coefficient of the ultraviolet absorber is measured as follows. 10.00 mg of an ultraviolet absorber is added to 1 liter of cyclohexane and dissolved by observation with naked eyes so that there is no undissolved product. This solution is poured into a quartz glass cell of 1 cm x 1 cm x 3 cm and the absorbance at a wavelength of 380 to 450 nm and an optical path length of 1 cm is measured using a U-3410 type spectrophotometer manufactured by Hitachi, Ltd. The maximum value? _Max of the molar extinction coefficient is calculated from the molecular weight (M _UV ) of the ultraviolet absorber and the maximum value (A _max ) of the measured absorbance by the following equation.

ε _max = [A _max / (10 × 10 ^-3 )] × M _UV

The light stabilizer is a compound known to have a function of capturing radicals mainly generated by light oxidation. Preferable examples of the light stabilizer include hindered amines such as compounds having a 2,2,6,6-tetraalkylpiperidine skeleton.

Examples of the lubricant include stearic acid, behenic acid, stearoamidoic acid, methylenebisstearoamide, hydroxystearic acid triglyceride, paraffin wax, ketone wax, octyl alcohol, and hardened oil.

The release agent is a compound having a function of facilitating release of a molded article from a mold. Examples of the release agent include higher alcohols such as cetyl alcohol and stearyl alcohol; Stearic acid monoglyceride, stearic acid monoglyceride, and stearic acid diglyceride. In the present invention, it is preferable to use a combination of a higher alcohol and a glycerin fatty acid monoester as a release agent. When the higher alcohols and the glycerin fatty acid monoester are used in combination, the mass ratio of the higher alcohol / glycerin fatty acid monoester is preferably in the range of 2.5 / 1 to 3.5 / 1, more preferably in the range of 2.8 / 1 to 3.2 / Is more preferable.

Examples of the impact resistance modifier include a core cell type modifier containing an acrylic rubber or a diene rubber as a core layer component; A modifier containing a plurality of rubber particles, and the like.

As the organic dye, a compound having a function of converting ultraviolet rays, which are considered harmful to the resin, to visible light is preferably used.

Examples of the light diffusing agent and the gloss removing agent include glass fine particles, polysiloxane crosslinked fine particles, crosslinked polymer fine particles, talc, calcium carbonate, barium sulfate and the like.

Examples of the fluorescent substance include a fluorescent pigment, a fluorescent dye, a fluorescent white dye, a fluorescent whitening agent, and a fluorescent whitening agent.

These additives may be used singly or in combination of two or more. These additives may be added to the polymerization reaction liquid when preparing the methacrylic resin or the polycarbonate resin, or may be added to the produced methacrylic resin or polycarbonate resin, or may be added when preparing the methacrylic resin composition . The total amount of the additives contained in the methacrylic resin composition used in the present invention is preferably 7% by mass or less, more preferably 5% by mass or less, and still more preferably 5% by mass or less, based on the methacrylic resin, Is not more than 4% by mass.

The method for preparing the methacrylic resin composition is not particularly limited. For example, a method of polymerizing a monomer mixture containing methyl methacrylate in the presence of a polycarbonate resin to produce a methacrylic resin, and a method of melt-kneading a methacrylic resin and a polycarbonate resin. Of these, the melt kneading method is preferable because the process is simple. Other polymers and additives may be mixed as needed during the melt-kneading, and the methacrylic resin may be mixed with other polymers and additives and then mixed with the polycarbonate resin. After the polycarbonate resin is mixed with other polymers and additives, It may be mixed with a resin. The kneading can be carried out, for example, by using a known mixing device or a kneading device such as a kneader rudder, an extruder, a mixing roll, a Banbury mixer or the like. Of these, a twin-screw extruder is preferred. The temperature for mixing and kneading can be appropriately adjusted depending on the melting temperature of the methacrylic resin and the polycarbonate resin to be used, and is preferably 110 to 300 占 폚. The methacrylic resin composition prepared as described above may be formed into a film in any form such as pellets, granules, powders, and the like.

The methacrylic resin composition of the present invention has a glass transition temperature of preferably 120 占 폚 or higher, more preferably 123 占 폚 or higher, even more preferably 124 占 폚 or higher. The upper limit of the glass transition temperature of the methacrylic resin composition is not particularly limited, but is preferably 140 占 폚, and more preferably 130 占 폚.

The Mw determined by measuring the methacrylic resin composition of the present invention by GPC is preferably 70,000 to 200,000, more preferably 72,000 to 160,000, and still more preferably 75,000 to 1200,000. The molecular weight distribution determined by measuring the methacrylic resin composition used in the present invention with GPC is preferably 1.2 to 2.5, more preferably 1.3 to 2.0. When the Mw or the molecular weight distribution is in this range, the molding processability of the methacrylic resin composition becomes favorable, and a molded article having excellent impact resistance and toughness is easily obtained.

The melt flow rate determined by measuring the methacrylic resin composition of the present invention under the conditions of a load of 230 캜 and a load of 3.8 ㎏ is preferably 0.1 to 6 g / 10 min, more preferably 0.5 to 5 g / 10 min, And preferably 1.0 to 3 g / 10 min.

The methacrylic resin composition of the present invention preferably has a haze of 1.0 mm in thickness of 1.0% or less, more preferably 0.7% or less, still more preferably 0.5% or less.

The film of the present invention is not particularly limited depending on its production method. The film of the present invention can be obtained, for example, by forming the methacrylic resin composition by a known method such as solution casting, melt casting, extrusion molding, inflation molding and blow molding. Of these, extrusion molding is preferable. According to the extrusion molding method, it is possible to obtain a film excellent in transparency, having improved toughness, excellent handling properties, and excellent balance between toughness, surface hardness and rigidity. The temperature of the methacrylic resin composition discharged from the extruder is preferably set at 160 to 270 캜, more preferably at 220 to 260 캜.

The methacrylic resin composition is extruded from a T-die in a molten state and then sandwiched between two or more of the mirror-surface rolls or the mirror-surface belt in order to obtain a film having good surface smoothness, good mirror gloss and low haze A method including molding is preferable. The mirror-surface roll or mirror-surface belt is preferably made of metal. The linear pressure between the pair of mirror rolls or the mirror-surface belt is preferably 10 N / mm or more, and more preferably 30 N / mm or more.

The surface temperature of the mirror-surface roll or mirror-surface belt is preferably 130 ° C or lower. It is preferable that at least one surface temperature of the pair of mirror-surface rolls or mirror-surface belts is 60 占 폚 or higher. By setting the surface temperature to such a value, the methacrylic resin composition discharged from the extruder can be cooled at a rate faster than the natural freezing, and the film of the present invention having an excellent surface smoothness and a low haze can be easily produced.

The film of the present invention may have been subjected to stretching treatment. The stretching treatment increases the mechanical strength and makes it possible to obtain a film which is hardly cracked. The stretching method is not particularly limited, and examples thereof include uniaxial stretching, simultaneous biaxial stretching, sequential biaxial stretching, and tubular stretching. The temperature at the time of stretching can be uniformly stretched and is preferably from 100 to 200 占 폚, more preferably from 120 to 160 占 폚, from the viewpoint of obtaining a high-strength film. In particular, when it is desired to increase the strength, it is preferable that the temperature is low, for example, 110 to 150 ° C is preferable, and 125 to 140 ° C is more preferable. It is preferable to stretch at a temperature not lower than the glass transition temperature of the methacrylic resin composition. The stretching is usually carried out at 100 to 5000% / min on a length basis. After the stretching, heat fixing is performed, or the film is relaxed, whereby a film with less heat shrinkage can be obtained. There is no limitation on the stretching magnification, but it is ordinarily about 1.5 to 8 times as large as the area ratio.

The amount of the methacrylic resin contained in the film of the present invention is preferably 78 to 98.7 mass%, and more preferably 85 to 97 mass% from the viewpoint of transparency and small retardation in the thickness direction.

The amount of the polycarbonate resin contained in the film of the present invention is preferably 1 to 3.8 mass%, more preferably 2 to 2.9 mass% from the viewpoint of small retardation in the thickness direction.

In the film of the present invention, the amount of the polymer processing aid contained therein is preferably 0.3 to 5.6 mass%, more preferably 0.5 to 2.9 mass% from the viewpoint of stretchability.

The thickness of the film of the present invention is not particularly limited, but when it is used as an optical film, its thickness is preferably 1 to 300 占 퐉, more preferably 10 to 50 占 퐉, and still more preferably 15 to 40 占 퐉.

The film of the present invention has a haze of preferably 0.2% or less, more preferably 0.1% or less at a thickness of 50 占 퐉. Thereby, surface gloss and transparency are excellent. Further, in optical applications such as a liquid crystal protective film and a light guiding film, the utilization efficiency of the light source is increased, which is preferable. In addition, it is preferable since the accuracy of forming the surface is excellent.

The film of the present invention preferably has an in-plane retardation Re in the in-plane directional retardation Re at a wavelength of 590 nm of preferably 40 nm or less, preferably 5 nm or less, more preferably 4 nm or less, still more preferably 3 nm or less, Preferably 2 nm or less, and most preferably 1 nm or less.

The film of the present invention preferably has a retardation Rth in the thickness direction with respect to light having a wavelength of 590 nm of -10 nm to 10 nm, more preferably -5 nm or more and 5 nm or less More preferably -4 nm or more and 4 nm or less, still more preferably -3 nm or more and 3 nm or less, particularly preferably -2 nm or more, 2 nm or less, and most preferably -1 nm or more, 1 nm or less.

When the retardation in the in-plane direction and the retardation in the thickness direction are within such a range, the influence on the display characteristics of the image display apparatus due to the retardation can be remarkably suppressed. More specifically, deformation of the 3D image in the case of unevenness of interference and use in a liquid crystal display device for 3D display can be remarkably suppressed.

The in-plane direction retardation Re and the thickness direction retardation Rth are values defined by the following equations, respectively.

Re = (nx - ny) xd

Rth = ((nx + ny) / 2 - nz) xd

Here, nx is the refractive index in the slow axis direction of the film, ny is the refractive index in the fast axis direction of the film, nz is the refractive index in the thickness direction of the film, and d (nm) is the thickness of the film. The slow axis refers to the direction in which the refractive index in the film plane becomes maximum, and the fast axis refers to the direction perpendicular to the slow axis in the plane.

Since the film of the present invention has high transparency, high heat resistance, small phase difference and thinness, it is preferable for a polarizer protective film and various films to be described later.

The polarizer of the present invention is a laminate of at least one polarizer protective film made of the film of the present invention. Preferably, the polarizer protective film of the present invention and a polarizer formed from a polyvinyl alcohol-based resin are laminated via an adhesive layer.

1, a polarizing plate according to a preferred embodiment of the present invention includes an adhesive layer 12, an easy-to-adhere layer 13, and a polarizer protective film of the present invention 14 are laminated in this order and the adhesive layer 15 and the optical film 16 are laminated in this order on the other surface of the polarizer 11. [

The polarizer formed of the polyvinyl alcohol-based resin can be obtained, for example, by uniaxially stretching a polyvinyl alcohol-based resin film by dying with a dichroic substance (typically, iodine or dichromatic dye). The polyvinyl alcohol based resin film can be obtained by forming a film of a polyvinyl alcohol based resin by any suitable method (for example, a method of forming a flexible film by dissolving a resin in water or an organic solvent, a casting method, an extrusion method) . The degree of polymerization of the polyvinyl alcohol-based resin is preferably 100 to 5000, more preferably 1400 to 4000. The thickness of the polyvinyl alcohol-based resin film used for the polarizer can be suitably set according to the purposes and applications of the LCD in which the polarizing plate is used, but is typically 5 to 80 탆.

The adhesive layer that can be formed on the polarizing plate of the present invention is not particularly limited as far as it is optically transparent. As the adhesive constituting the adhesive layer, for example, an aqueous adhesive, a solvent adhesive, a hot melt adhesive, an active energy ray curable adhesive and the like can be used. Of these, water-based adhesives and active energy ray-curable adhesives are preferred.

The water-based adhesive may be in the form of an aqueous solution or may be a latex. Examples of the water-based adhesive include, but are not limited to, a vinyl polymer type, a gelatin type, a vinyl type latex type, a polyurethane type, an isocyanate type, a polyester type and an epoxy type. If necessary, a catalyst such as a crosslinking agent, other additives, or an acid may be added to such an aqueous adhesive. As the water-based adhesive, it is preferable to use an adhesive containing a vinyl polymer, and as the vinyl polymer, a polyvinyl alcohol-based resin is preferable. The polyvinyl alcohol-based resin may contain a water-soluble crosslinking agent such as boric acid, borax, glutaraldehyde, melamine or oxalic acid. Particularly in the case of using a polyvinyl alcohol-based polymer film as a polarizer, it is preferable to use an adhesive containing a polyvinyl alcohol-based resin in terms of adhesiveness. Furthermore, an adhesive containing a polyvinyl alcohol-based resin having an acetacetyl group is more preferable in terms of improving durability. The water-based adhesive is usually used as an adhesive composed of an aqueous solution, and usually contains 0.5 to 60% by mass of solids.

As the active energy ray curable adhesive, besides the use of a compound having a monofunctional or bifunctional (meth) acryloyl group or a compound having a vinyl group as a curable component, an epoxy compound or an oxetane compound and a photoacid generator as main components Based curing component may be used. As the active energy ray, an electron beam or ultraviolet ray can be used.

The adhesive may contain a metal compound filler. The flowability of the adhesive layer can be controlled by the metal compound filler and the film thickness is stabilized to obtain a polarizing plate having a good appearance and uniform surface irregularity and no deviation in adhesion.

The method of forming the adhesive layer is not particularly limited. For example, it can be formed by applying the adhesive to an object, followed by heating or drying. The application of the adhesive may be carried out with respect to the polarizer protective film or optical film of the present invention, or may be carried out with respect to the polarizer. After the adhesive layer is formed, the polarizer protective film or the optical film and the polarizer can be pushed and aligned to laminate them. For lamination, a roll press machine, a flat press machine, or the like can be used. The heating drying temperature and drying time are appropriately determined depending on the kind of the adhesive.

The thickness of the adhesive layer in the dried state is preferably 0.01 to 10 占 퐉, more preferably 0.03 to 5 占 퐉.

The easy adhesion layer which can be formed on the polarizing plate of the present invention is to improve the adhesion between the polarizing protective film and the surface on which the polarizing film is in contact. The adhesion facilitating layer can be formed by an easy adhesion treatment or the like. Examples of the adhesion facilitating treatment include surface treatments such as corona treatment, plasma treatment, and low-pressure UV treatment. The adhesion-facilitating layer can be formed by a method of forming an anchor layer, or a combination of the surface treatment and the method of forming an anchor layer. Among them, a corona treatment, a method of forming an anchor layer, and a method of using them in combination are preferable.

The anchor layer includes, for example, a silicon layer having a reactive functional group. The material of the silicon layer having a reactive functional group is not particularly limited, and examples thereof include alkoxysilane compounds containing an isocyanate group, amino group-containing alkoxysilanols, mercapto group-containing alkoxysilanols, carboxy-containing alkoxysilanols, Alkoxy silane compounds containing vinyl type unsaturated groups, alkoxy silane compounds containing halogen groups, and alkoxy silane compounds containing isocyanate groups. Of these, amino-based silanol is preferred. By adding a titanium-based catalyst or a tin-based catalyst for efficiently reacting silanol to the silanol, the adhesion can be strengthened. Other additives may be added to the silicon having the reactive functional group. Other additives include tackifier such as terpene resin, phenol resin, terpene-phenol resin, rosin resin and xylene resin; Stabilizers such as ultraviolet absorbers, antioxidants and heat-resistant stabilizers. As the anchor layer, a layer formed by saponifying a cellulose acetate butyrate resin is also exemplified.

The anchor layer is formed by coating and drying by a known technique. The thickness of the anchor layer in the dried state is preferably 1 to 100 nm, more preferably 10 to 50 nm. At the time of coating, the anchor layer forming chemical liquid may be diluted with a solvent. The diluting solvent is not particularly limited, but alcohols may be mentioned. The dilution concentration is not particularly limited, but is preferably 1 to 5% by mass, and more preferably 1 to 3% by mass.

The optical film 16 may be the polarizer protective film of the present invention or any other suitable optical film. The optical film to be used is not particularly limited, and examples thereof include a film made of a cellulose resin, a polycarbonate resin, a cyclic polyolefin resin, a methacrylic resin, or the like.

Cellulose resins are esters of cellulose and fatty acids. Specific examples of the cellulose ester-based resin include cellulose triacetate, cellulose diacetate, cellulose tripropionate, and cellulose dipropionate. Of these, cellulose triacetate is particularly preferable. Many products of cellulose triacetate are commercially available and are advantageous in terms of availability and cost. Examples of commercially available products of cellulose triacetate include UV-50, UV-80, SH-80, TD-80U, TD-TAC and UZ- KC series manufactured by Konica Minolta Co., Ltd., and the like.

The cyclic polyolefin resin is a general term of a resin polymerized by using a cyclic olefin as a polymerization unit and includes, for example, those described in JP-A-1-240517, JP-A-3-14882, JP- 3-122137 and the like. Specific examples thereof include ring-opened (co) polymers of cyclic olefins, addition polymers of cyclic olefins, copolymers of cyclic olefins and? -Olefins such as ethylene and propylene (typically, random copolymers) A graft polymer modified by an unsaturated carboxylic acid or a derivative thereof, and hydrides thereof. Specific examples of cyclic olefins include norbornene monomers.

As the cyclic polyolefin resin, various products are commercially available. Specific examples thereof include trade names "Zeonex" and "Zeonoa" manufactured by Nippon Zeon Corporation, "Aton" manufactured by JSR Corporation, "Topaz" manufactured by Polyplastics Co., and "APEL" have.

As the methacrylic resin used for the optical film such as the optical film 16, any appropriate methacrylic resin may be employed within the range not hindering the effect of the present invention. (Meth) acrylic acid copolymer, methacrylic acid methyl- (meth) acrylate copolymer, methyl methacrylate-acrylate ester- (meth) acrylate copolymer, Styrene copolymer (MS resin), a polymer having an alicyclic hydrocarbon group (e.g., methyl methacrylate-cyclohexyl methacrylate copolymer, methyl methacrylate-methyl methacrylate copolymer, (Meth) acrylate norbornyl copolymer).

As specific examples of the methacrylic resin used for the optical film such as the optical film 16, for example, acrylate VH or acryphet VRL20A manufactured by Mitsubishi Rayon Co., Ltd., Japanese Laid-Open Patent Publication No. 2013-033237 or WO2013 / 005634 An acrylic resin having a ring structure in the molecule described in WO2005 / 108438, an acrylic resin having a ring structure in the molecule described in JP-A-2009-197151, an acrylic resin obtained by copolymerizing methyl methacrylate and maleimide- Methacrylic resin having a high glass transition temperature (Tg) obtained by intramolecular crosslinking or intramolecular cyclization.

As the methacrylic resin, a methacrylic resin having a lactone ring structure may be used. High heat resistance, high transparency, and high mechanical strength by biaxial stretching.

As the methacrylic resin having a lactone ring structure, there can be mentioned, for example, JP-A 2000-230016, JP-A 2001-151814, JP-A 2002-120326, JP-A 2002-254544, And a methacrylic resin having a lactone ring structure described in Patent Publication No. 2005-146084.

The polarizing plate of the present invention can be used in an image display apparatus. Specific examples of the image display device include a self-emission type display device such as an electroluminescence (EL) display, a plasma display (PD), a field emission display (FED), and a liquid crystal display device. The liquid crystal display has a liquid crystal cell and the polarizer disposed on at least one side of the liquid crystal cell.

The methacrylic resin composition of the present invention has a high transparency when the methacrylic resin and the polycarbonate resin are uniformly used and has a high retardation in the thickness direction even when stretched. In addition, the film obtained is highly stretchable. Therefore, according to the methacrylic resin composition of the present invention, a film which is thin, has excellent in-plane uniformity and high surface smoothness can be obtained. Further, stretching at a low temperature becomes possible, and a film having high strength can be obtained. Further, by setting the syndiotacticity (rr) of the methacrylic resin to a specific value, it is possible to provide a film having a high heat resistance and a small heat shrinkage ratio.

Example

Hereinafter, the present invention will be described in detail with reference to examples and comparative examples, but the present invention is not limited to the following examples. The measurement of the physical properties and the like was carried out by the following method.

(Polymerization conversion ratio)

Inert CAP 1 (df = 0.4 μm, 0.25 mm ID × 60 m) manufactured by GL Sciences Inc. was connected as a column to a gas chromatograph GC-14A manufactured by Shimadzu Corporation. The injection temperature was 180 ° C. and the detector temperature The temperature was raised to 180 占 폚, the column temperature was raised from 60 占 폚 (held for 5 minutes) to 200 占 폚 at a temperature raising rate of 10 占 폚 / min, and held for 10 minutes. Measurements were carried out, Respectively.

(Weight average molecular weight (Mw), molecular weight distribution (Mw / Mn))

The Mw and the molecular weight distribution of the methacrylic resin and the methacrylic resin composition obtained in each of Production Examples, Examples and Comparative Examples were measured by gel permeation chromatography (GPC) under the following conditions, and the molecular weight of the standard polystyrene And one value was calculated. The baseline indicates that the slope of the peak on the high molecular weight side of the GPC chart changes from zero to positive when viewed from the fast retention time and from the negative to zero when the slope of the peak on the low molecular weight side is viewed from the fast retention time side And the line connecting the points.

GPC apparatus: manufactured by Toso Co., Ltd., HLC-8320

Detector: differential refractive index detector

Column: TS KGel Super Multipore HZM-M manufactured by Toso Co., Ltd. and Superhz 4000 were connected in series.

Eluent: tetrahydrofuran

Flow rate of eluent: 0.35 ml / min

Column temperature: 40 DEG C

Calibration curve: Created using 10 points of standard polystyrene

(Viscosity average molecular weight (Mv))

The viscosity average molecular weight of the polycarbonate resin was determined by measuring the specific viscosity? _Sp at 20 占 폚 of a solution obtained by dissolving 0.5 g of polycarbonate resin in 100 ml of methylene chloride using a Uberolde viscometer and calculating a value satisfying the following Schnell equation Was calculated from the intrinsic viscosity [?] Of a methylene chloride solution at 20 占 폚.

η _sp / c = [η] + 0.45 × [η] ² c

([Eta] is an intrinsic viscosity, c = 0.5 in the above condition)

[?] = 1.23 10 ^-4 Mv ^0.83

(Syndiotacticity (rr) of three consecutive characters)

The ¹ H-NMR spectrum of the methacrylic resin was measured using a nuclear magnetic resonance apparatus (ULTRA SHIELD 400 PLUS manufactured by Bruker) and deuterated chloroform as a solvent at room temperature and the number of integration times of 64 times. The area X of 0.6 to 0.95 ppm area and the area Y of 0.6 to 1.35 ppm area when TMS was set to 0 ppm were measured from the spectrum and then the syndiotacticity rr of three- Was calculated by the formula: (X / Y) x 100.

(Glass transition temperature Tg)

The methacrylic resin, the polycarbonate resin and the methacrylic resin composition were once heated up to 230 占 폚 by using a differential scanning calorimeter (DSC-50 (part number), manufactured by Shimadzu Corporation) according to JIS K7121, , And then the DSC curve was measured under the condition of raising the temperature from room temperature to 230 캜 at a rate of 10 캜 / minute. The midpoint glass transition temperature, which is obtained from the DSC curve measured at the second rise in temperature, is defined as the glass transition temperature in the present invention.

(Melt mass flow rate (MFR))

In each of the examples and comparative examples, the methacrylic resin as the raw material of the methacrylic resin composition used in the production of the film was measured under the conditions of 230 占 폚 and a load of 3.8 kg for 10 minutes in accordance with JIS K7210.

(Melt Volume Flow Rate (MVR))

The polycarbonate resin as a raw material of the methacrylic resin composition used in the production of the film in each of the examples and comparative examples was measured under the conditions of 300 캜 and 1.2 kg load for 10 minutes in accordance with JIS K7210.

(Surface smoothness)

The surfaces of the biaxially stretched films obtained in each of the Examples and Comparative Examples were visually observed and the surface smoothness was evaluated according to the following criteria.

A: The surface is smooth.

B: The surface has irregularities.

(Average degree of polymerization of the polymer processing aid)

The measurement was carried out at 20 占 폚 using chloroform as a solvent using an auto-dilution type capillary viscometer (Uebero type, capillary inner diameter = 0.5 mm), and the degree of polymerization in terms of PMMA was determined.

(Heat shrinkage ratio)

A test piece of 100 mm x 30 mm was cut out from the biaxially stretched film obtained in each of the Examples and Comparative Examples and a straight line having a length of 70 mm was written on the surface of the biaxially stretched film and heated in a hot air circulating heating oven maintained at a temperature of 110 캜 After heating for 30 minutes, the length (L (mm)) of the straight line written was read in scale, and the heat shrinkage rate was calculated by the following formula.

Heat shrinkage percentage (%) = (70 - L) / 70 x 100

(Total light transmittance)

Test specimens of 50 mm x 50 mm were cut out from the biaxially stretched films obtained in the respective Examples and Comparative Examples and the total light transmittance was measured using a haze meter (HM-150 manufactured by Murakami Color Research Laboratory) according to JIS K7361-1 Respectively. The evaluation of the methacrylic resin composition was carried out by molding a molded article having a thickness of 1.0 mm in a hot press, and measuring the total light transmittance.

(Hayes)

Test specimens of 50 mm x 50 mm were cut out from the biaxially stretched films obtained in the respective Examples and Comparative Examples and the haze thereof was measured using a haze meter (HM-150 manufactured by Murakami Color Research Laboratory) according to JIS K7136. The evaluation of the methacrylic resin composition was carried out by forming a molded article having a thickness of 1.0 mm in a hot press and measuring the haze.

(Thickness direction retardation Rth and in-plane direction retardation Re)

Test specimens of 40 mm x 40 mm were cut out from the biaxially stretched films obtained in each of the Examples and Comparative Examples. Using the automatic birefringence system (KOBRA-WR manufactured by Oji Measurement Co., Ltd.), at a temperature of 23 ± 2 ° C and a humidity of 50 ± 5%, a three-dimensional refractive index nx , ny and nz were determined, and the thickness direction retardation Rth and in-plane direction retardation Re were calculated from the above-mentioned formulas. The thickness d (nm) of the test piece was measured using Digimatic Indicator (manufactured by Mitsutoyo Corporation), and the refractive index n was measured with a digital precision refractometer (KPR-20 manufactured by Curie Optical Co., Ltd.).

(Extensibility)

When the unoriented films obtained in the respective Examples and Comparative Examples were biaxially stretched, the stretchability was evaluated by the following criteria. The unstretched film was cut into 100 mm x 100 mm and stretched by a pantograph type biaxial stretching tester (manufactured by Toyobo Co., Ltd.) at a stretching temperature of glass transition temperature +10 DEG C, a stretching speed of 120% / min in one direction, After being biaxially stretched at a draw ratio of 2 times (four times in area ratio), the resultant was held for 10 seconds and then cooled.

A: It was possible to obtain more than 5 samples out of 10 samples without crack and crack.

B: The film without cracks or cracks could be obtained for only 4 samples out of 10 samples.

PREPARATION EXAMPLE 1 A 5 L glass reaction vessel equipped with a stirring blade and a three-way cock was substituted with nitrogen. To this were added at room temperature 1600 g of toluene, 2.49 g (10.8 mmol) of 1,1,4,7,10,10-hexamethyltriethylenetetramine, 2,6-di-t- 53.5 g (30.9 mmol) of a toluene solution of tert-butyl-4-methylphenoxy) aluminum and a solution of sec-butyllithium at a concentration of 1.3 M (solvent: 95% by mass of cyclohexane and 5% by mass of n-hexane) (10.3 mmol). While stirring, 550 g of methyl methacrylate distilled and purified therefrom was added dropwise at -20 占 폚 for 30 minutes. After completion of the dropwise addition, the mixture was stirred at -20 占 폚 for 180 minutes. The color of the solution changed from yellow to colorless. The polymerization conversion rate of the methyl methacrylate at this point was 100%. To the obtained solution, 1500 g of toluene was added and diluted. Subsequently, the diluted solution was poured into 100 kg of methanol to obtain a precipitate. The obtained precipitate was dried at 80 占 폚 and 140 Pa for 24 hours to obtain a copolymer having Mw of 96100, a molecular weight distribution of 1.07, syndiotacticity (rr) of 83%, a glass transition temperature of 133 占 폚, To obtain a methacrylic resin [PMMA1] having a proportion of the structural units derived from the monomer (A) of 100% by mass.

PREPARATION EXAMPLE 2 A 5 L glass reaction vessel equipped with a stirring blade and a three-way cock was substituted with nitrogen. To this were added at room temperature 1600 g of toluene, 2.49 g (10.8 mmol) of 1,1,4,7,10,10-hexamethyltriethylenetetramine, 2,6-di-t- 6.15 g (10.3 mmol) of a toluene solution of 53.5 g (30.9 mmol) of a toluene solution of tert-butyl-4-methylphenoxy) aluminum and a solution of sec- respectively. While stirring, 550 g of methyl methacrylate distilled and purified therefrom was added dropwise at 20 DEG C over 30 minutes. After completion of dropwise addition, the mixture was stirred at 20 占 폚 for 90 minutes. The color of the solution changed from yellow to colorless. The polymerization conversion rate of the methyl methacrylate at this point was 100%.

To the obtained solution, 1500 g of toluene was added and diluted. Subsequently, the diluted solution was poured into 100 kg of methanol to obtain a precipitate. The resulting precipitate was dried at 80 DEG C and 140 Pa for 24 hours to obtain a copolymer having an Mw of 81400, a molecular weight distribution of 1.08, a syndiotacticity (rr) of 73%, a glass transition temperature of 131 DEG C and a methyl methacrylate To obtain a methacrylic resin [PMMA2] having a content of a structural unit derived from 100% by mass.

PREPARATION EXAMPLE 3 In an autoclave equipped with a stirrer and a sampling tube, nitrogen was substituted. To this, 0.0052 parts by mass of purified methyl methacrylate, 0.0052 parts by mass of 2,2'-azobis (2-methylpropionitrile) (hydrogen-withdrawing ability: 1%, 1 hour half-life temperature: 83 ° C) And 0.28 parts by mass of octyl mercaptan were added and stirred to obtain a raw material liquid. Nitrogen was sent to the raw material liquid to remove dissolved oxygen in the raw material liquid.

The raw material liquid was added to the plastic reactor connected with the autoclave and the piping up to 2/3 of the capacity. The polymerization was first initiated by keeping the temperature at 140 < 0 > C. When the polymerization conversion rate reached 55 mass%, the raw material liquid was supplied from the autoclave to the molding reactor at an average residence time of 150 minutes, and the reaction liquid was discharged from the molding reactor at a flow rate corresponding to the feed flow rate of the raw material liquid The temperature was maintained at 140 캜 and the polymerization reaction was changed to a continuous flow system. After the conversion, the polymerization conversion rate in the steady state was 55 mass%.

The reaction liquid withdrawn from the shaping reactor in the steady state was supplied to a multitubular heat exchanger having a temperature of 230 DEG C, which was cooled to a flow rate at which the average residence time was 2 minutes, and then heated. Subsequently, the warmed reaction liquid was introduced into a flash evaporator, and volatile matter containing an unreacted monomer as a main component was removed to obtain a molten resin. The molten resin from which the volatile components were removed was fed to a twin screw extruder having an internal temperature of 260 DEG C and discharged into a strand shape and cut into a pelletizer to give a pellet-like Mw of 82000, a molecular weight distribution of 1.85, a syndiotacticity (rr) Of 52%, a glass transition temperature of 120 占 폚, and a content of a structural unit derived from methyl methacrylate of 100% by mass.

Production Example 4 The same operations as in Production Example 3 were carried out except that the amount of n-octylmercaptan was changed to 0.225 parts by mass to obtain a copolymer having Mw of 103600, a molecular weight distribution of 1.81 and syndiotacticity (rr) of 52 %, A glass transition temperature of 120 占 폚, and a proportion of a structural unit derived from methyl methacrylate of 100% by mass.

Production Example 5 The same operations as in Production Example 3 were carried out except that the amount of n-octyl mercaptan was changed to 0.30 parts by mass to obtain a copolymer having Mw of 76400, a molecular weight distribution of 1.81, syndiotacticity (rr) of 53 %, A glass transition temperature of 119 占 폚, and a content of a structural unit derived from methyl methacrylate of 100% by mass.

Production Example 6 57 parts by mass of a methacrylic resin [PMMA2] and 43 parts by mass of a methacrylic resin [PMMA4] were mixed and kneaded extruded at 250 占 폚 with a twin screw extruder (trade name: KZW20TW-45MG-NH- To prepare a methacrylic resin [PMMA6].

SUMIPEC MHF (manufactured by Sumitomo Chemical Co., Ltd.) was used as a methacrylic resin [PMMA7].

Table 1 shows the physical properties of the above [PMMA1] to [PMMA7].

The polycarbonate resin used in the examples is described below, and the physical properties thereof are shown in Table 2.

PC1: Toughron LC1700 (product number), manufactured by Idemitsu Kosan Co., Ltd.; MVR (300 캜, 1.2 ㎏) = 40 cm 3/10 min, Mv = 16200

PC2: manufactured by Mitsubishi Engineering Plastic Co., Ltd., YuPiron HL-4000 (part number); MVR (300 캜, 1.2 ㎏) = 60 cm 3/10 min, Mv = 15100

PC3: manufactured by Sumikastar Theory Polycarbonate, SD POLYCA SD-2201

W (part number); MVR (300 캜, 1.2 ㎏) = 115 cm 3/10 min, Mv = 13000

PC4: manufactured by Sumikastar Theory Polycarbonate, SD POLYCA TR-2001

(Part number); MVR (300 캜, 1.2 ㎏) = 200 cm 3/10 min, Mv = 11400

PC5: AL071, manufactured by Mitsubishi Engineering Plastic Co., Ltd.; MVR (300 캜, 1.2 ㎏) = 1000 cm 3/10 min or more (flowability was high and accurate measurement was difficult)

Mv = 5500

PC6: a mixture of 50 parts by mass of PC4 and 50 parts by mass of PC5; MVR (300 占 폚, 1.2 kg) = 1000 cm3 / 10 minutes or more (fluidity was high and accurate measurement was difficult), Mv = 8500

The polymer processing aid used in the examples is described below. Here, MMA means a structural unit derived from methyl methacrylate, and BA means a structural unit derived from butyl acrylate.

B1: Metabrene P570A (average degree of polymerization: 2384, MMA 53 mass% / BA 47 mass%) manufactured by Mitsubishi Rayon Co.,

B2: Metabrene P550A (average polymerization degree: 7734, MMA 88 mass% / BA 12 mass%) manufactured by Mitsubishi Rayon Co.,

B3: Parabolite K125P (average degree of polymerization: 19874, MMA 79 mass% / BA 21 mass%) manufactured by Kureha Co.,

B4: Metabrene P530A (average degree of polymerization: 24455, MMA 80 mass% / BA 20 mass%) manufactured by Mitsubishi Rayon Co.,

B5: Metabrene P531A (average polymerization degree: 37162, MMA 80 mass% / BA 20 mass%) manufactured by Mitsubishi Rayon Co.,

2,4,6-tris (2-hydroxy-4-hexyloxy-3-methylphenyl) -1,3,5-triazine (LA-F70 manufactured by ADEKA) was used as the ultraviolet absorber.

≪ Example 1 >

100 parts by mass of methacrylic resin [PMMA1], 2.5 parts by mass of polycarbonate resin [PC1] and 2 parts by mass of processing aid [B2] were mixed and kneaded in a twin-screw extruder (trade name: KZW20TW-45MG-NH-600) Followed by kneading extrusion at 250 DEG C to prepare a methacrylic resin composition [1]. The obtained methacrylic resin composition [1] was hot-pressed to form a plate-shaped molded article of 50 mm x 50 mm x 1.0 mm, and the total light transmittance, haze and glass transition temperature were measured. Table 3 shows the physical properties of the methacrylic resin composition [1].

The methacrylic resin composition [1] was dried at 80 DEG C for 12 hours. The methacrylic resin composition [1] was extruded from a 150 mm wide T-die at a resin temperature of 260 占 폚 using a 20 mm? Single-axis extruder (manufactured by OCS), rolled with a roll having a surface temperature of 85 占 폚, , And an undrawn film having a thickness of 160 mu m was obtained.

The unstretched film obtained by the above procedure was cut into 100 mm x 100 mm and stretched at a stretching temperature of glass transition temperature + 10 占 폚, a stretching speed of 500% / min in one direction, (Biaxially stretched at a stretching ratio of 2 times in one direction (4 times in terms of area ratio), cooled to 100 占 폚 or less over 2 minutes, and taken out to obtain a biaxially oriented film having a thickness of 40 占 퐉. Table 3 shows the measurement results of the surface smoothness, heat shrinkage percentage, total light transmittance, haze, in-plane retardation Re, thickness direction retardation Rth and stretchability of the stretched film produced from the unstretched film for the obtained biaxial oriented film.

≪ Examples 2 to 11 and Comparative Examples 1 to 7 >

The methacrylic resin compositions [2] to [18] were prepared in the same manner as in Example 1 except that the formulations shown in Tables 3 and 4 were used. The obtained methacrylic resin compositions [2] to [18] were hot-pressed to form a plate-shaped molded body of 50 mm x 50 mm x 1.0 mm, and the total light transmittance, haze and glass transition temperature were measured. The physical properties of the methacrylic resin compositions [2] to [18] are shown in Tables 3 and 4.

A biaxial oriented film was obtained in the same manner as in Example 1 except that the methacrylic resin compositions [2] to [18] were used instead of the methacrylic resin composition [1]. The evaluation results are shown in Tables 3 and 4.

(Polarizer)

A polyvinyl alcohol film having an average degree of polymerization of 2400, a degree of saponification of 99.9 mol% and a thickness of 75 mu m was immersed in hot water at 30 DEG C for 60 seconds to swell. Then, it was stretched to 3.5 times while being dyed in an iodine solution of 0.3 mass% (weight ratio: iodine / potassium iodide = 0.5 / 8) at 30 DEG C for 1 minute. Thereafter, the substrate was immersed in an aqueous solution of 4% by mass of boric acid at 65 캜 for 0.5 minutes, and stretched so as to have a total draw ratio of 6 times. After stretching, the film was dried in an oven at 70 DEG C for 3 minutes to obtain a polarizer having a thickness of 22 mu m.

≪ Production of polarizer X >

The biaxially stretched film of Example 8 was used as the polarizer protective film A. 16.8 g of a polyester urethane (trade name: Superflex 210, solid content: 33%, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) , 2.0 g of 1 mass% of ammonia water, 0.42 g of colloidal silica (manufactured by Fuso Chemical Co., Ltd., Qwatron PL-3, solid content: 20 mass%) and 76.6 g of pure water were mixed to obtain a composition for bonding.

The obtained composition for bonding was applied to the corona discharge treated surface of the biaxially oriented film of Example 8 subjected to the corona discharge treatment with a bar coater so that the thickness after drying was 100 nm. Thereafter, the film was placed in a hot-air dryer (110 ° C), and the composition for adhesion was dried for about 5 minutes to form an easy-to-adhere layer on the biaxially stretched film of Example 8.

Next, 38.3 parts by mass of N-hydroxyethyl acrylamide (manufactured by Kojin Co.), 19.1 parts by mass of tripropylene glycol diacrylate (Aronix M-220, Toagosei Co., Ltd.) and acryloylmorpholine Ltd.) and 1.4 parts by mass of a photopolymerization initiator (trade name: KAYACURE DETX-S, diethyl thioxanthone, manufactured by Nippon Kayaku Co., Ltd.) were mixed and stirred at 50 ° C for 1 hour to obtain an active energy ray curable adhesive.

The active energy ray-curable adhesive was applied to the easy-adhesion layer side of the polarizer protective film A to a thickness of 500 nm after drying. Thereafter, the polarizer protective film A was laminated on both sides of the above-mentioned polarizer with the use of a small-sized laminator via an active energy ray curable adhesive. The active energy ray curable adhesive was cured by irradiating ultraviolet rays of 1000 mJ / cm 2 from the both sides of the bonded polarizer protective film A using an IR heater at 50 캜 and a cumulative irradiation amount of 1000 mJ / cm 2, A polarizing plate X having a transparent polarizer protective film A on both surfaces thereof was obtained. The polarizing plate X thus prepared was placed in a constant-temperature and humidity-humidity chamber at 80 ° C and RH of 90%, and the degree of deterioration of the polarizer after 100 hours was visually observed. As a result, no deterioration was observed.

≪ Production of Polarizer Y >

A triacetylcellulose film having a thickness of 40 占 퐉 was saponified by immersing in a 10% aqueous solution of sodium hydroxide (60 占 폚) for 30 seconds, followed by washing with water for 60 seconds to obtain a polarizer protective film B.

20 parts by mass of methylol melamine was added to 100 parts by mass of a polyvinyl alcohol-based resin having an acetacetyl group (average degree of polymerization: 1200, saponification degree: 98.5 mol%, acetacetyl group degree of deformation: 5 mol% To obtain an aqueous solution having a solid content concentration of 0.5%. The obtained aqueous solution was used as an adhesive composition under a temperature condition of 30 캜.

The polarizer protective film B was applied with the adhesive composition after 30 minutes from the preparation to a thickness of 50 nm after drying. Thereafter, the polarizer protective film B was laminated on both sides of the above-mentioned polarizer via the adhesive composition using a small laminator, put in a hot-air dryer (70 DEG C) and dried for 5 minutes to obtain a polarizing plate Y. [ The prepared polarizing plate Y was placed in a constant temperature and humidity chamber of 80 ° C and 90% RH, and the degree of deterioration of the polarizer after 100 hours was visually observed. As a result, deterioration was observed on the entire surface.

This application claims priority based on Japanese Patent Application No. 2014-88810, filed on April 23, 2014, and incorporates herein all of its disclosure.

Industrial availability

Since the methacrylic resin composition of the present invention has a high transparency, a small retardation in the thickness direction, a high heat resistance and a thin stretchability, the methacrylic resin composition can be used as a polarizer protective film, a retardation film, a liquid crystal protective plate, A light guiding film, a transparent conductive film formed by coating silver nanowires or carbon nanotubes on the surface, and a front plate for various displays. In particular, the film of the present invention is preferable for a polarizer protective film because of a small retardation.

Since the film of the present invention has high transparency and heat resistance, it can be used as an IR cut film, a crime prevention film, a shatterproof film, a decorative film, a metal edible film, a solar cell back sheet, a front sheet for a flexible solar cell, Shrink films, and films for in-mold labeling.

11: Polarizer
12: adhesive layer
13: Adhesion facilitating layer
14: polarizer protective film
15: adhesive layer
16: Optical film

Claims (14)

A methacrylic resin composition containing a methacrylic resin, a polycarbonate resin and a polymer processing aid,
The methacrylic resin preferably has a structural unit derived from methyl methacrylate of 80 mass% or more, a weight average molecular weight of 200,000 or less,
Wherein the polycarbonate resin has a viscosity average molecular weight of 1000 or more and 32000 or less and the content of the polycarbonate resin relative to 100 parts by mass of the methacrylic resin is 1 part by mass or more and 4 parts by mass or less,
The polymer processing aid has an average degree of polymerization of 3,000 or more and 40,000 or less,
Wherein the content of the polymer processing aid in relation to 100 parts by mass of the methacrylic resin is 0.3 parts by mass or more and 6 parts by mass or less,
Wherein the total amount of the methacrylic resin and the polycarbonate resin contained in the methacrylic resin composition is 80 mass% or more. The method according to claim 1,
Wherein the methacrylic resin has a syndiotacticity (rr) of not less than 50% and a content of a structural unit derived from methyl methacrylate of not less than 92 mass% and not more than 100 mass%. 3. The method according to claim 1 or 2,
Wherein the methacrylic resin has a syndiotacticity (rr) of 58% or more and 85% or less. 4. The method according to any one of claims 1 to 3,
Wherein the methacrylic resin has a content of a structural unit derived from methyl methacrylate of 99 mass% or more. 5. The method according to any one of claims 1 to 4,
Wherein the polycarbonate resin has a viscosity average molecular weight of 5000 or more and 18000 or less. 6. The method according to any one of claims 1 to 5,
Wherein the methacrylic resin composition has a weight average molecular weight of 70,000 to 200,000. 7. The method according to any one of claims 1 to 6,
Wherein the methacrylic resin composition has a molecular weight distribution of 1.2 to 2.5. A molded article comprising the methacrylic resin composition according to any one of claims 1 to 7. A film comprising the methacrylic resin composition according to any one of claims 1 to 7. 10. The method of claim 9,
A film having a thickness of 10 to 50 占 퐉. 11. The method according to claim 9 or 10,
Biaxially stretched film with an area ratio of 1.5 to 8 times. 12. The method according to any one of claims 9 to 11,
A film used as a polarizer protective film. 13. A polarizing plate comprising at least one film according to claim 12. 100 parts by mass of a methacrylic resin having a structural unit derived from methyl methacrylate of 80% by mass or more and a weight average molecular weight of 200,000 or less,
1 part by mass or more and 4 parts by mass or less of a polycarbonate resin having a viscosity average molecular weight of 1000 or more and 32000 or less,
And at least three components selected from the group consisting of not less than 0.3 parts by mass and not more than 6 parts by mass of a polymer processing aid having an average degree of polymerization of not less than 3,000 and not more than 40,000.

Images