TW201623415A - Acrylic film - Google Patents

Abstract

To provide an acrylic film with high glass transition temperature, and having chemical resistance, whitening resistance and high surface hardness. An acrylic film obtained from a methacrylic resin composition containing a methacrylic resin [1] with a triad syndiotacticity (rr) of at least 65% and an elastomer component [2] containing at least 30 mass% of structural units derived from an acrylic acid ester in a proportion of 60/40-99/1 methacrylic resin [1]/elastomer component [2] mass ratio. The length of dispersed phases derived from the elastomer component [2] when test pieces of the acrylic film were stained with phosphotungstic acid being 10-300 nm.

Description

Acrylic film

The present invention relates to an acrylic film comprising a methacrylic resin composition, and more particularly to an acrylic system having high transparency, bending whitening resistance, high rigidity, high heat resistance and excellent surface smoothness. film.

The methacrylic resin has high transparency and can be used as a material of a molded body used in an optical member, an illumination member, a sign member, a decorative member, or the like. However, since the glass transition temperature is about 110 ° C, the molding system containing the methacrylic resin has a problem that it is easily deformed by heat.

A methacrylic resin having a high degree of glass transition temperature is known as a methacrylic resin having a high degree of syndiotacticity. The method for producing a methacrylic resin having a high degree of syndiotacticity is, for example, a method of anionic polymerization (see Patent Documents 1 and 2). In addition, a resin composition in which a reinforcing agent having a multilayer structure is blended in a methacrylic resin having a high degree of syndiotacticity to improve impact strength and bending strength is known (see Patent Document 3). Further, an acrylic film in which an acrylic block copolymer is blended in a methacrylic resin is also known (see Patent Document 4).

However, in the technique of Patent Document 3, for the preferred reinforcement The disclosure of the agent is not sufficient. Further, in the technique of Patent Document 4, heat resistance is insufficient, and the use of the obtained acrylic film is limited.

In addition, in recent years, as the thin film formation of a liquid crystal display device or the like progresses, the film used for the polarizer protective film or the like tends to be thinned. In such a case, there is a problem in that the quality of the polarizer is lowered in order to elongate the film containing the cellulose triacetate which has been used conventionally. Therefore, in the thinning of the liquid crystal display device, development of a polarizer protective film in place of cellulose triacetate has been a problem.

Therefore, the acrylic film is reviewed as a candidate for a new polarizer protective film. However, in addition to being brittle, the acrylic film has a problem that the rigidity of the film itself is lowered by film formation, resulting in a decrease in surface hardness.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. Hei 3-263412

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2002-327012

[Patent Document 3] Japanese Patent Laid-Open No. Hei 6-287398

[Patent Document 4] International Publication Bulletin 2014/073216

An object of the present invention is to provide an acrylic film having high transparency, high glass transition temperature, and having chemical resistance, whitening resistance, and high surface hardness.

In order to achieve the above object, the results of the research are focused on, and the present invention has been completed. The following describes its aspect.

(1): an acrylic film comprising a ternary display between the methacrylic resin [1]/elastomer component [2] in a mass ratio of 60/40 to 99/1 (rr) An acrylic film having a methacrylic resin [6] of 65% or more and a methacrylic resin composition containing 30% by mass or more of the elastomer component [2] derived from the acrylate structural unit, characterized in that the acrylic acid When the thin film of the film is dyed with phosphotungstic acid, the long axis of the dispersed phase derived from the above elastomer component [2] is 10 to 300 nm.

(2) The acrylic film according to (1), wherein the methacrylic resin [1] has a molecular weight distribution of 1.5 or less.

(3) The acrylic film according to (1) or (2), wherein the mass ratio of the methacrylic resin [1] / elastomer component [2] is from 80/20 to 99/1.

(4) The acrylic film according to any one of (1) to (3), wherein the elastomer component [2] contains a polymer (b1) comprising a structural unit having a methacrylate as a main component. a block copolymer in combination with a polymer (b2) having a structural unit containing an acrylate.

(5) The acrylic film according to any one of (1) to (4) wherein the elastomer component [2] contains a core-shell graft copolymer.

(6) The acrylic film according to any one of (1) to (5), wherein the methacrylic resin composition further contains an ultraviolet absorber.

(7) The acrylic film according to any one of (1) to (6) wherein the methacrylic resin composition is the same as the above methacrylic resin [1] The total amount of the elastomer component [2] is 100 parts by mass, and further contains 1 to 10 parts by mass of the polycarbonate resin.

(8): A laminated film using the acrylic film according to any one of (1) to (7).

(9): A polarizer protective film comprising the acrylic film according to any one of (1) to (7).

(10): A method for producing an acrylic film, which is obtained by melt-kneading a triplet between a methacrylic resin [1]/elastomer component [2] at a mass ratio of 60/40 to 99/1 a methacrylic resin [1] having a degree of (rr) of 65% or more and an elastomer component [2] containing 30% by mass or more of a structural unit derived from an acrylate to obtain a methacrylic resin composition, and then the composition A method for producing an acrylic film obtained by molding a base acrylic resin composition, wherein a long axis of the dispersed phase derived from the elastomer component [2] when the sheet of the acrylic film is dyed with phosphotungstic acid is 10 to 300 nm.

(11) The method for producing an acrylic film according to (10), wherein the acrylic film is further extended.

(12) The method for producing an acrylic film according to (10) or (11), which further comprises melt-kneading the polycarbonate resin to obtain the methacrylic resin composition.

(13) The method for producing an acrylic film according to any one of (10) to (12), wherein, by a unit comprising a polymer (b1) constituting a structural unit having a methacrylate as a main component a step of polymerizing and a step of polymerizing a monomer constituting the polymer (b2) having a structural unit mainly composed of an acrylate to produce a block copolymer (B), and It is contained as the above elastomer component [2].

The acrylic film of the present invention has high transparency, high glass transition temperature, chemical resistance, whitening resistance, and high surface hardness.

[Formation of the Invention]

The acrylic film of the present invention contains a methacrylic resin composition containing a methacrylic resin [1] and an elastomer component [2]. In other words, the acrylic film of the present invention contains a methacrylic resin [1] and an elastomer component [2].

The methacrylic resin [1] is a triad exhibiting a degree of (rr) of 65% or more, preferably 70 to 90%, more preferably 72 to 85%. When the degree is between 65% or more, the glass transition temperature of the methacrylic resin composition of the present invention can be increased, and the composition is excellent in heat resistance. Moreover, it tends to be excellent in drug resistance.

Here, the triplet shows the degree of agreement (rr) (hereinafter, also referred to as "syntax (rr)"), which is a chain of three consecutive structural units (triad: triad). The two chains (dual group: diad) are all ratios of racemic (labeled rr). Further, in the chain of structural units (dual group: diad) in the polymer molecule, the same stereo arrangement is referred to as meso (meso), and the opposite is referred to as racem (racemo), respectively denoted as m, r. The triad shows the degree of agreement (rr) (%) in deuterated chloroform, and the 1H-NMR spectrum was measured at 30 ° C. From the spectrum, TMS was measured at 0 ppm, 0.6~ The area (X) of the region of 0.95 ppm and the area (Y) of the region of 0.6 to 1.35 ppm can be obtained by the formula: (X/Y) × 100.

The amount of the methacrylic resin [1] contained in the acrylic film of the present invention is preferably 60 to 99% by mass, and is 70 to 99 by mass from the viewpoint of achieving high glass transition temperature and good moldability. % is better, preferably 80 to 99% by mass. When it is less than 60% by mass, the surface hardness and rigidity of the acrylic film are not preferable. When it exceeds 99% by mass, the toughness such as the punching workability of the acrylic film is impaired.

The weight average molecular weight of the methacrylic resin [1] (hereinafter, referred to simply as "Mw") is preferably 40,000 to 150,000, more preferably 40,000 to 120,000, and even more preferably 50,000 to 100,000. When the Mw is less than 40,000, the toughness such as the punching workability of the acrylic film tends to decrease, and when it exceeds 150,000, the film formation tends to be difficult and the processing condition range tends to be narrow.

The methacrylic resin [1] is a ratio of Mw to a number average molecular weight (hereinafter, referred to simply as "Mn") (Mw/Mn; hereinafter, this value is referred to as a "molecular weight distribution"). 1.01~1.8 is better, 1.03~1.5 is better, and 1.05~1.3 is better. When a methacrylic resin [1] having a molecular weight distribution within this range is used, a molded article excellent in mechanical strength and particularly excellent in mechanical properties and latent properties at a high temperature can be easily obtained. Moreover, it is easy to obtain a film excellent in drug resistance. Mw and Mn can be controlled by adjusting the kind and amount of the polymerization initiator used in the production of the methacrylic resin [1]. Further, Mw and Mn are values converted to the molecular weight of standard polystyrene by a chromatogram measured by a gel permeation chromatography (GPC).

The glass transition temperature of the methacrylic resin [1] is preferably 125 ° C or more, more preferably 128 ° C or more, and still more preferably 130 ° C or more. The upper limit of the glass transition temperature of the methacrylic resin [1] is preferably 140 ° C or more. The glass transition temperature can be controlled by adjusting the molecular weight and the degree of syntax (rr). As the glass transition temperature of the methacrylic resin [1] becomes higher, the glass transition temperature of the obtained methacrylic resin composition increases, and the acrylic film composed of the methacrylic resin composition is less likely to cause heat shrinkage or the like. Deformation.

The content of the methacrylic resin [1] derived from the structural unit derived from methacrylate is preferably 90% by mass or more, more preferably 95% by mass or more, even more preferably 98% by mass or more, and particularly preferably 99% by mass or more. It is especially good, and 100% by mass is the best. Examples of the methacrylates include alkyl methacrylates such as methyl methacrylate, ethyl methacrylate and butyl methacrylate; aryl methacrylates such as phenyl methacrylate; and methacrylic rings. A cycloalkyl methacrylate such as hexyl ester or decyl methacrylate. Among these, alkyl methacrylate is preferred, and methyl methacrylate is preferred.

In the structural unit derived from the above methacrylic acid ester, the content of the structural unit derived from methyl methacrylate is preferably 90% by mass or more, more preferably 95% by mass or more, and more preferably 95% by mass or more. 98% by mass or more is more preferable, and more preferably 99% by mass or more, and 100% by mass is most preferable.

The methacrylic resin [1] may contain structural units other than the structural unit derived from methacrylate, and examples thereof include methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, and propylene. An alkyl acrylate such as 2-ethylhexyl acrylate; an aryl acrylate such as phenyl acrylate; a cycloalkyl acrylate such as cyclohexyl acrylate or decyl acrylate; an aromatic vinyl compound such as styrene or α-methyl styrene; A structural unit derived from a vinyl monomer having only one carbon-carbon double bond in one of propyleneamine, methacrylamide, acrylonitrile, methacrylonitrile or the like.

The production method of the methacrylic resin [1] is not particularly limited. From the viewpoint of productivity, in the anionic polymerization method, a methacrylic resin is produced by adjusting the polymerization temperature, the polymerization time, the type and amount of the chain transfer agent, and the type and amount of the polymerization initiator [1]. The method is better.

Examples of the anionic polymerization method include an anion polymerization method in which an organic alkali metal compound is used as a polymerization initiator in the presence of an inorganic acid salt such as an alkali metal or an alkaline earth metal salt (refer to Japanese Special Fair 7-25859). No.) a method of performing anionic polymerization in the presence of an organoaluminum compound using an organic alkali metal compound as a polymerization initiator (refer to Japanese Patent Laid-Open No. Hei 11-335432); using an organic rare earth metal complex as a polymerization initiator; A method of performing anionic polymerization (refer to Japanese Patent Laid-Open No. Hei 6-93060) and the like.

In order to produce a methacrylic resin [1], an anionic polymerization method is preferably carried out using an alkyl lithium such as n-butyllithium, a second butyllithium, an isobutyllithium or a t-butyllithium as a polymerization initiator. . Further, from the viewpoint of productivity, it is preferred that the organoaluminum compound coexist. The organoaluminum compound may be exemplified by the following formula: A1R1R2R3 (wherein R1, R2 and R3 are each independently represent an alkyl group which may have a substituent, a cycloalkyl group which may have a substituent, and An aryl group having a substituent, an aralkyl group which may have a substituent, an alkoxy group which may have a substituent, an aryloxy group which may have a substituent, or an N,N-disubstituted amine group. Further, R2 and R3 are compounds represented by the above-exemplified aryldioxy group which may have a substituent.

Specific examples of the organoaluminum compound include, for example, isobutylbis(2,6-di-tert-butyl-4-methylphenoxy)aluminum, isobutylbis(2,6-di-third Butylphenoxy)aluminum, isobutyl [2,2'-methylenebis(4-methyl-6-t-butylphenoxy)]aluminum, and the like. Further, in the anionic polymerization method, in order to control the polymerization reaction, an ether or a nitrogen-containing compound may be allowed to coexist.

The elastomer component [2] contained in the acrylic film of the present invention is important to contain 30% by mass or more of the structural unit derived from the acrylate. When the amount is less than 30% by mass, the obtained acrylic film is inferior in toughness, and for example, it is liable to be defective or broken due to a punching test or the like. The content of the structural unit derived from the acrylate in the elastomer component [2] is preferably 35 mass% or more and 90 mass% or less, more preferably 40 mass% or more and 80 mass% or less.

Examples of the acrylates include alkyl acrylates such as methyl acrylate, ethyl acrylate and butyl acrylate; aryl acrylates such as phenyl acrylate and benzyl acrylate; and cycloalkyl acrylates such as cyclohexyl acrylate and decyl acrylate. Preferably, the alkyl acrylate is preferred, and the butyl acrylate is preferred.

The elastomer component [2] may contain structural units other than the structural unit derived from the acrylate, and examples thereof include methyl methacrylate, ethyl methacrylate, propyl methacrylate, and butyl methacrylate. , alkyl methacrylate such as 2-ethylhexyl methacrylate; methyl propyl acrylate Aryl methacrylate such as phenyl acrylate; cycloalkyl methacrylate such as cyclohexyl methacrylate or decyl methacrylate; aromatic vinyl compound such as styrene or α-methyl styrene; A structural unit derived from a vinyl monomer having only one carbon-carbon double bond in one of a molecule such as an amine, methacrylamide, acrylonitrile or methacrylonitrile.

The dispersion form of the dispersed phase derived from the elastomer component [2] in the acrylic film of the present invention is not particularly limited, and examples thereof include a spherical shape, an ellipsoid shape, a rod shape, a flat shape, and a rope shape. The size of the dispersed phase derived from the elastomer component [2], particularly the major axis of the dispersed phase, is important because it affects the properties of the film such as transparency and bending whitening resistance. Therefore, when the sheet of the acrylic film of the present invention is subjected to phosphotungstic acid dyeing, it is important that the long axis of the dispersed phase of the elastomer component [2] is 10 to 300 nm. The major axis size of the dispersed phase was measured by the following method.

The sheet used for the measurement of the phosphotungstic acid dyeing was prepared in the following manner. The sheet A was obtained by cutting with a microtome in the thickness direction of the film and in the extrusion direction. The sheet B is obtained by cutting with a microtome in the thickness direction of the film and in a direction perpendicular to the extrusion direction. Sheets A and B were each stained with phosphotungstic acid and observed under a transmission electron microscope. In the sheet A, 100 dispersed phases in which the film was dyed in the extrusion direction were extracted, and an average of the major axes was obtained, and the long axis average value (A-Av) was obtained. In the sheet B, 100 pieces of the dispersed phase in which the film was dyed in the direction perpendicular to the extrusion direction were extracted, and the average of the major axes was obtained, and the long axis average value (B-Av) was obtained. The larger of the long axis average value (A-Av) and the long axis average value (B-Av) is taken as the long axis derived from the dispersed phase of the elastomer component [2]. Moreover, when dyeing with phosphotungstic acid, especially butyl acrylate is effectively dyed to accurately grasp the elastomer component [2] The state of the dispersed phase.

When the long axis of the dispersed phase derived from the elastomer component [2] according to the above measurement method is less than 10 nm, the transparency is excellent and brittle, which is not preferable. On the other hand, when it exceeds 300 nm, it is not preferable because the whitening property of the bending is poor. The value is preferably 50 nm or more and 290 nm or less, and more preferably 100 nm or more and 270 nm or less.

The amount of the elastomer component [2] contained in the acrylic film of the present invention is preferably 40 to 1% by mass, more preferably 30 to 1% by mass, still more preferably 20 to 1% by mass. When the elastomer component exceeds 40% by mass, the chemical resistance and heat resistance are not preferable, and when it is less than 1% by mass, the toughness is not preferable. Further, when the acrylic film of the present invention is stretched, the puncture property can be maintained even if the amount of the elastomer component [2] is reduced. Therefore, in the acrylic film of the present invention to be extended, the content of the elastomer component [2] is preferably from 1 to 20% by mass, more preferably from 1 to 10% by mass.

The elastomer component [2] is not particularly limited as long as the content of the structural unit derived from the acrylate is 30% by mass or more, and examples thereof include a linear polymer, a graft copolymer containing a core-shell type, and a soft block. A block copolymer composed of a hard block or the like may also be a mixture thereof. Among them, a block copolymer composed of a soft block and a hard block, a core-shell type graft copolymer, and a mixture thereof are preferable in that impact resistance and toughness can be imparted without impairing other physical properties.

The glass transition temperature on the low temperature side of the elastomer component [2] is preferably 20 ° C or lower, more preferably -20 ° C or lower. When it is 20 ° C or more, the toughness which impairs the punching workability and the like is not preferable.

Methacrylic acid contained in the acrylic film of the present invention The total amount of the resin [1] and the elastomer component [2] is preferably 80% by mass or more, more preferably 85% by mass or more, even more preferably 90% by mass or more, and particularly preferably 95% by mass or more. 98.5 mass% or more is the best.

Only the methacrylic resin [1] and the elastomer component [2] are kneaded, and the melt flow rate in the conditions of 230 ° C and 3.8 kg load is preferably 0.1 g/10 min or more, and 0.2 to 30 g / 10 minutes is better, preferably 0.5 to 20 g/10 minutes, and 1.0 to 10 g/10 minutes is the best.

Further, in the case where only the methacrylic resin [1] and the elastomer component [2] are kneaded, the glass transition temperature is preferably 120 ° C or higher, more preferably 123 ° C or higher, and even more preferably 124 ° C or higher, and 130 ° C. The above is the best.

The block copolymer which is one of the best forms of the elastomer component [2] used in the present invention will be described.

The block copolymer (B) which can be used as the elastomer component [2] used in the present invention is a block copolymer having a methacrylate polymer block (b1) and an acrylate polymer block (b2). . The block copolymer (B) may have only one methacrylate polymer block (b1), or may have plural. Further, the block copolymer (B) may have only one acrylate polymer block (b2), or may have plural numbers.

The methacrylate polymer block (b1) is a polymer having a structural unit mainly composed of methacrylate. The proportion of the structural unit derived from the methacrylate in the methacrylate polymer block (b1) is preferably 80% by mass or more, more preferably 90% by mass or more, and even more preferably 95% by mass or more. It is particularly preferable to be 98% by mass or more.

Examples of the methacrylate include methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, and methyl propyl acrylate. Isoic acid acrylate, n-butyl methacrylate, isobutyl methacrylate, butyl methacrylate, butyl methacrylate, amyl methacrylate, isoamyl methacrylate, A N-hexyl acrylate, cyclohexyl methacrylate, 2-ethylhexyl methacrylate, pentadecyl methacrylate, dodecyl methacrylate, isodecyl methacrylate, phenyl methacrylate , benzyl methacrylate, phenoxyethyl methacrylate, 2-hydroxyethyl methacrylate, 2-methoxyethyl methacrylate, glycidyl methacrylate, allyl methacrylate Wait. Among these, from the viewpoint of improving transparency and heat resistance, methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, and tertiary butyl methacrylate are used. An alkyl methacrylate such as cyclohexyl methacrylate or isodecyl methacrylate is preferred, and methyl methacrylate is more preferred. These methacrylates may be polymerized in a single type or in combination of two or more kinds to form a methacrylate polymer block (b1).

The methacrylate polymer block (b1) may contain constituent units derived from monomers other than methacrylate without impairing the object and effect of the present invention. The ratio of the constituent units of the monomer other than the methacrylate contained in the methacrylate polymer block (b1) is 20% by mass or less, preferably 10% by mass or less, and 5% by mass or less. Preferably, the range of 2% by mass or less is particularly preferred.

Examples of the monomer other than the methacrylate include an acrylate, an unsaturated carboxylic acid, an aromatic vinyl compound, an olefin, a conjugated diene, acrylonitrile, methacrylonitrile, acrylamide, and methyl group. Acrylamide, vinyl acetate, vinyl pyridine, vinyl ketone, vinyl chloride, dichloroethylene, and difluoroethylene. By using the methacrylate The monomers may be copolymerized with the above methacrylate in a single type or in combination of two or more kinds to form a methacrylate polymer block (b1).

From the viewpoint of improving the transparency of the methacrylic resin composition, the methacrylate polymer block (b1) is preferably a polymer having a refractive index of 1.485 to 1.495.

The weight average molecular weight of the methacrylate polymer block (b1) is preferably 5,000 or more and 150,000 or less, more preferably 8,000 or more and 120,000 or less, still more preferably 12,000 or more and 100,000 or less.

When the methacrylate polymer block (b1) in the block copolymer (B) is plural, the composition ratio and molecular weight of each structural unit constituting the methacrylate polymer block (b1) may be the same or Different.

When the methacrylate polymer block (b1) is plural, the maximum weight average molecular weight Mw (b1) is preferably 12,000 or more and 150,000 or less, more preferably 15,000 or more and 120,000 or less, and still more preferably 20,000 or more and 100,000 or less. . When there is only one methacrylate polymer block (b1) in the block copolymer (B), the weight average molecular weight of the methacrylate polymer block (b1) becomes Mw (b1). Further, when the plurality of methacrylate polymer blocks (b1) are present in the block copolymer (B), when the weight average molecular weights of the plurality of methacrylate polymer blocks (b1) are the same, The weight average molecular weight becomes Mw (b1).

In the methacrylic resin composition used in the present invention, the ratio of the weight average molecular weight Mw[1] to Mw(b1) of the methacrylic resin [1], that is, Mw[1]/Mw(b1) is 0.5 or more. 2.5 or less is preferably 0.6 or more and 2.3 or less, and more preferably 0.7 or more and 2.2 or less. Acrylic film made of methacrylic resin composition when Mw[1]/Mw(b1) is less than 0.5 There is a tendency that the impact resistance is lowered and the surface smoothness is lowered. On the other hand, when Mw[1]/Mw(b1) is too large, the molded article produced from the methacrylic resin composition tends to have surface smoothness and temperature dependency of haze. It is considered that when Mw[1]/Mw(b1) is in the above range, the size of the dispersibility of the block copolymer (B) in the methacrylic resin (A) becomes small, so that low haze regardless of temperature change is exhibited. The change in haze over a wide temperature range is reduced.

The ratio of the methacrylate polymer block (b1) in the block copolymer (B) is 40% by mass or more and 90% by mass or less from the viewpoints of transparency, flexibility, moldability, and surface smoothness. Preferably, it is more preferably 45 mass% or more and 80 mass% or less. When the ratio of the methacrylate polymer block (b1) in the block copolymer (B) is within the above range, the methacrylic resin composition of the present invention or the molded article formed therefrom may have transparency. Flexibility, bending resistance, impact resistance, flexibility, and the like are excellent. When a plurality of methacrylate polymer blocks (b1) are contained in the block copolymer (B), the above ratio is calculated based on the total mass of the methacrylate polymer blocks (b1).

The acrylate polymer block (b2) is a polymer having a structural unit mainly composed of an acrylate. The ratio of the structural unit derived from the acrylate of the acrylate polymer block (b2) is preferably 45 mass% or more, more preferably 50 mass% or more, and 60 mass% or more, more preferably 90 mass% or more. It is especially good.

Examples of the acrylate include methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, secondary butyl acrylate, and tertiary butyl acrylate. Ester, amyl acrylate, isoamyl acrylate, n-hexyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, pentadecyl acrylate, lauryl acrylate, isodecyl acrylate, phenyl acrylate, acrylic acid Benzyl ester, phenoxyethyl acrylate, 2-hydroxyethyl acrylate, 2-methoxyethyl acrylate, glycidyl acrylate, allyl acrylate, and the like. These acrylates may be polymerized in a single type or in combination of two or more kinds to form an acrylate polymer block (b2).

The acrylate polymer block (b2) may contain a structural unit derived from a monomer other than the acrylate, as long as the object and effect of the present invention are not impaired. The ratio of the structural unit derived from the monomer other than the acrylate contained in the acrylate polymer block (b2) is preferably 55% by mass or less, more preferably 50% by mass or less, and even more preferably 40% by mass or less. Preferably, it is particularly good at 10% by mass or less.

Examples of the single system other than the acrylate include methacrylate, unsaturated carboxylic acid, aromatic vinyl compound, olefin, conjugated diene, acrylonitrile, methacrylonitrile, acrylamide, and methacryl Amine, vinyl acetate, vinyl pyridine, vinyl ketone, vinyl chloride, dichloroethylene and difluoroethylene. The acrylate polymer block (b2) is formed by copolymerizing the monomers other than the acrylates in a single type or in combination of two or more kinds thereof with the acrylate.

The acrylate polymer block (b2) contains an alkyl acrylate and a (meth)acrylic acid aromatic acid, and the viewpoint of improving the refractive index of the methacrylic resin composition used in the present invention or improving transparency. Ester is better. Examples of the alkyl acrylate system include methyl acrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate, and 2-ethyl acrylate. Hexyl hexyl ester and lauryl acrylate. Among these, n-butyl acrylate and 2-ethylhexyl acrylate are preferred.

The (meth)acrylic aromatic ester is an aromatic acrylate or a (meth)acrylic aromatic ester, and the compound containing an aromatic ring is a combination of (meth)acrylic acid and an ester. Examples of the (meth)acrylic aromatic esters include phenyl acrylate, benzyl acrylate, phenoxyethyl acrylate, styrene acrylate, phenyl methacrylate, benzyl methacrylate, and methyl group. Phenyloxyethyl acrylate and styrene methacrylate. Among them, phenyl methacrylate, benzyl methacrylate, phenoxyethyl methacrylate, and benzyl acrylate are preferred. When the acrylate polymer block (b2) is composed of an alkyl acrylate and an aromatic (meth) acrylate, the acrylate polymer block (b2) is composed of a structural unit 50~ derived from an alkyl acrylate. 90% by mass and 50 to 10% by mass of the structural unit derived from the (meth)acrylic acid aromatic ester are preferably included, and the structural unit derived from the alkyl acrylate is 60 to 80% by mass and derived from the (meth)acrylic acid aromatic group. The structural unit of the group ester is preferably 40 to 20% by mass.

From the viewpoint of improving the transparency of the methacrylic resin composition of the present invention, the acrylate polymer block (b2) is preferably a polymer having a refractive index of 1.485 to 1.495.

The weight average molecular weight of the acrylate polymer block (b2) is 5,000 or more and 120,000 or less, preferably 15,000 or more and 110,000 or less, and more preferably 30,000 or more and 100,000 or less.

When a plurality of acrylate polymer blocks (b2) are present in the block copolymer (B), the composition ratio and molecular weight of the structural units constituting the acrylate polymer block (b2) may be the same or different from each other.

When there are a plurality of acrylate polymer blocks (b2), the largest weight average molecular weight Mw (b2) thereof is 30,000 or more and 120,000 or less, preferably 40,000 or more and 110,000 or less, and more preferably 50,000 or more and 100,000 or less. When Mw (b2) is small, the acrylic film produced from the methacrylic resin composition tends to have low impact resistance. On the other hand, when Mw (b2) is large, the molded article produced from the methacrylic resin composition tends to have a low surface smoothness. When there is only one methacrylate polymer block (b2) in the block copolymer (B), the weight average molecular weight of the methacrylate polymer block (b2) becomes Mw (b2). Further, when the plurality of methacrylate polymer blocks (b1) are present in the block copolymer (B), when the weight average molecular weights of the plurality of methacrylate polymer blocks (b1) are the same, The weight average molecular weight becomes Mw (b2).

Further, the weight average molecular weight of the methacrylate polymer block (b1) and the weight average molecular weight of the acrylate polymer block (b2) are in the process of producing the block copolymer (B), during polymerization, and polymerization. The value calculated from the weight average molecular weight of the intermediate product and the final product (block copolymer (B)) measured after sampling. Each weight average molecular weight is a value converted to a standard polystyrene measured by GPC (gel permeation chromatography).

The ratio of the acrylate polymer block (b2) in the block copolymer (B) is preferably 10% by mass or more and 60% by mass or less from the viewpoints of transparency, flexibility, moldability, and surface smoothness. It is more preferably 20% by mass or more and 55% by mass or less. When the ratio of the acrylate polymer block (b2) in the block copolymer (B) is in the above range, the methacrylic resin composition of the present invention or the molded article formed therefrom has impact resistance and The softness and the like are excellent. When a plurality of acrylate polymer blocks (b2) are contained in the block copolymer (B), the above ratio is calculated based on the total mass of all the acrylate polymer blocks (b2).

The block copolymer (B) is not particularly limited depending on the form of bonding of the methacrylate polymer block (b1) and the acrylate polymer block (b2). For example, one of the ends of the acrylate polymer block (b2) is attached to one end of the methacrylate polymer block (b1) (the diblock copolymer of the (b1)-(b2) structure); One end of the acrylate polymer block (b2) is bonded to both ends of the methacrylate polymer block (b1) ((b2)-(b1)-(b2) structure triblock copolymer) a one-block copolymer of (b1)-(b2)-(b1) structure in which one end of the methacrylate polymer block (b1) is attached to both ends of the acrylate polymer block (b2) And a block copolymer in which the methacrylate polymer block (b1) and the acrylate polymer block (b2) are linked in a row.

Further, for example, a block copolymer in which a plurality of (b1)-(b2) structure block copolymers are joined to form a radial structure ([(b1)-(b2)-]nX structure); One end of the block copolymer of the (b2)-(b1) structure is bonded to a block copolymer of a radial structure ([(b2)-(b1)-]nX structure); plural (b1)-(b2) One-end of the block copolymer of the structure -(b1) is bonded to a block copolymer of a radial structure ([(b1)-(b2)-(b1)-]nX structure); plural (b2)-( One end of the block copolymer of the b1)-(b2) structure is bonded to a star-shaped block copolymer of a radial structure block copolymer ([(b2)-(b1)-(b2)-]nX structure)) Or a block copolymer having a branched structure or the like. Moreover, X here represents a coupling agent residue. Among these, diblock copolymers, triblock copolymers, and star inlays The segment copolymer is preferably a diblock copolymer of (b1)-(b2) structure, a triblock copolymer of (b1)-(b2)-(b1) structure, [(b1)-(b2)- The star-type block copolymer of the nX structure and the star block copolymer of the [(b1)-(b2)-(b1)-]nX structure are more preferable.

Further, the block copolymer (B) may be a polymer block (b3) having a methacrylate polymer block (b1) and an acrylate polymer block (b2). The main structural unit constituting the polymer block (b3) is a structural unit derived from a monomer other than methacrylate and acrylate. Examples of the monomer include olefins such as ethylene, propylene, 1-butene, isobutylene, and 1-octene; conjugated dienes such as butadiene, isoprene, and geranene; and styrene and α. - aromatic vinyl compounds such as methyl styrene, p-methyl styrene and m-methyl styrene; vinyl acetate, vinyl pyridine, acrylonitrile, methacrylonitrile, ketene, vinyl chloride, dichloroethylene, Fluorine, acrylamide, methacrylamide, ε-caprolactone, and valerolactone.

In the block copolymer (B), the form of bonding of the methacrylate polymer block (b1), the acrylate polymer block (b2), and the polymer block (b3) is not particularly limited. The bonding form of the block copolymer (B) comprising the methacrylate polymer block (b1), the acrylate polymer block (b2) and the polymer block (b3) may, for example, be: (b1) a block copolymer of the structure -(b2)-(b1)-(b3), a block copolymer of the structure of (b3)-(b1)-(b2)-(b1)-(b3), and the like. When the number of the polymer blocks (b3) in the block copolymer (B) is plural, the composition ratio and molecular weight of the structural units constituting the polymer block (b3) may be the same or different from each other.

The block copolymer (B) can be in the molecular chain as needed or The terminal of the molecular chain has a functional group such as a hydroxyl group, a carboxyl group, an acid anhydride, and an amine group.

The weight average molecular weight Mw (B) of the block copolymer (B) is preferably 52,000 or more and 400,000 or less, more preferably 60,000 or more and 300,000 or less. When the weight average molecular weight of the block copolymer (B) is small, sufficient melt tension cannot be maintained in melt extrusion molding, and a good acrylic film cannot be obtained, and the mechanical properties such as the breaking strength of the obtained acrylic film are Reduce the tendency. On the other hand, when the weight average molecular weight of the block copolymer (B) is large, the viscosity of the molten resin becomes high, and irregularities or unmelted substances (high molecular weight) due to fine wrinkles are generated on the surface of the acrylic film obtained by melt extrusion molding. The protrusion caused by the material tends to fail to obtain a good plate-shaped formed body.

Further, the molecular weight distribution of the block copolymer (B) is preferably 1.01 or more and 2.00 or less, more preferably 1.05 or more and 1.60 or less. When the molecular weight distribution is within such a range, the content of the unmelted material which causes the formation of the projections in the acrylic film of the present invention can be made extremely small. Further, the molecular weight distribution is a ratio of the weight average molecular weight to the number average molecular weight, which is a value obtained by converting the molecular weight of the standard polystyrene measured by GPC (gel permeation chromatography).

The refractive index of the above block copolymer (B) is preferably 1.485 to 1.495, more preferably 1.487 to 1.493. When the refractive index is within this range, the transparency of the methacrylic resin composition is improved. Further, the "refractive index" in the present specification means a value measured at a measurement wavelength of 587.6 nm (氘 line: d-line) as described in the following examples.

The method for producing the block copolymer (B) is not particularly limited, and a method according to a conventional method can be employed. Generally used, for example: will constitute each A method of living polymerization of a monomer of a polymer block. The method of the living polymerization is, for example, a method of performing anionic polymerization in the presence of an inorganic acid salt such as an alkali metal or an alkaline earth metal salt using an organic alkali metal compound as a polymerization initiator; and using an organic alkali metal compound as a polymerization. a method of performing anion polymerization in the presence of an organoaluminum compound; a method of polymerizing using an organic rare earth metal complex as a polymerization initiator; using an α-haloester compound as a starter in the presence of a copper compound A method of performing radical polymerization or the like is carried out. Further, for example, a monomer constituting each block may be polymerized using a polyvalent radical polymerization initiator or a polyvalent radical chain transfer agent to produce a mixture containing the block copolymer (B) used in the present invention. Method and so on. Among these methods, in particular, the block copolymer (B) is obtained in high purity, and the control of molecular weight and composition ratio is easy and economical, and an organic alkali metal compound is used as a polymerization initiator in the organoaluminum. A method of performing anionic polymerization in the presence of a compound is preferred.

Next, a core-shell type graft copolymer which is one of the preferred forms of the elastomer [2] used in the present invention will be described. The laminated structure of the core-shell type graft copolymer is not particularly limited as long as it has the outermost layer and the inner layer. For example, the core (inner layer) is a crosslinked rubber polymer (I) - the shell (the outermost layer) is a thermoplastic polymer (II) of two layers of polymer particles, and the core (inner layer) is a polymer (III) - inner shell (inner layer) is a crosslinked rubber polymer (I) - outer shell (outermost layer) is a thermoplastic polymer (II) of three layers of polymer particles, core (inner layer) is crosslinked rubber polymer (I) - first The inner shell (inner layer) is a polymer (III) - the second inner shell (inner layer) is a crosslinked rubber polymer (I) - the outer shell (outermost layer) is a thermoplastic polymer (II) of 4 layers of polymer particles, etc. A variety of laminate structures. Such In the core (inner layer), the polymer (III)-inner shell (inner layer) is a crosslinked rubber polymer (I) - the outermost layer (outermost layer) is a thermoplastic polymer (II) Preferably, the three-layer polymer particles composed of the following layers are more preferable: the core (inner layer) is an alkyl acrylate containing 80 to 99.95 mass% of methyl methacrylate and having an alkyl group having 1 to 8 carbon atoms. a layer of a polymer (III) obtained by polymerizing a monomer of 0 to 19.95 mass% and a crosslinking monomer of 0.05 to 2 mass%; and an inner shell (inner layer) containing an alkyl group having a carbon number of 1 to 8 a layer of a crosslinked rubber polymer (I) obtained by polymerizing 80% to 98% by mass of an alkyl acrylate monomer, 1 to 19% by mass of an aromatic vinyl monomer, and 1 to 5% by mass of a crosslinkable monomer; The outer shell (outermost layer) is a thermoplastic polymer (II) obtained by polymerizing 0 to 20% by mass of an alkyl acrylate monomer having 80 to 100% by mass of methyl methacrylate and having an alkyl group having 1 to 8 carbon atoms. Into the layer. From the viewpoint of the transparency of the core-shell type graft copolymer, it is preferred to select the difference in refractive index of the adjacent layers to be less than 0.005, more preferably less than 0.004, and more preferably less than 0.003 in each layer. The polymer is better.

The mass ratio of the inner layer to the outermost layer of the core-shell graft copolymer is preferably 60/40 to 95/5, more preferably 70/30 to 90/10. In the inner layer, the proportion of the layer containing the crosslinked rubber polymer (I) is preferably 20 to 70% by mass, more preferably 30 to 50% by mass.

The average particle size of the core-shell graft copolymer is preferably from 0.05 to 1 μm, more preferably from 0.07 to 0.5 μm, still more preferably from 0.10 to 0.4 μm. When a core-shell type graft copolymer having an average particle diameter within such a range, particularly, an average particle diameter of 0.15 to 0.3 μm is used, the toughness can be exhibited by mixing in a small amount, thereby impairing rigidity and surface hardness. In addition, the average particle diameter in the present specification is a volume-based particle diameter measured by a light scattering method. The arithmetic mean of the cloth.

The method for producing the core-shell type graft copolymer is not particularly limited, but is preferably an emulsion polymerization method. Specifically, it can be obtained by emulsion polymerization of a monomer constituting the crosslinked rubber polymer (I). Further, the core-shell type graft copolymer which is a component of the crosslinked rubber particles is obtained by emulsion-polymerizing a monomer constituting the innermost layer of the core-shell type graft copolymer to obtain seed particles, and is sequentially added in the presence of the seed particles. The monomers constituting each layer are obtained by sequentially polymerizing to the outermost layer.

Examples of the emulsifier used in the emulsion polymerization method include dialkyl sulfosuccinate such as sodium octyl sulfosuccinate and sodium dilauryl sulfosuccinate, and dodecylbenzene. An alkyl sulfonate such as sodium sulfonate or an alkyl sulfate such as sodium lauryl sulfate; a polyoxyethylene alkyl ether of a nonionic emulsifier; a polyoxyethylene nonylphenyl ether; and the like; Polyoxyethylene nonylphenyl ether sulfate such as polyoxyethylene nonylphenyl ether sulfate, emulsifier, polyoxyethylene alkyl ether sulfate such as sodium polyoxyethylene alkyl ether sulfate, and polyoxyethylene tridecane An alkyl ether carboxylate such as sodium acetate. These may be used alone or in combination of two or more. Further, the average number of repeating units of the ethylene oxide unit in the exemplary compounds of the anionic emulsifier and the nonionic-anionic emulsifier is preferably 30 or less, and 20 or less, in order to prevent the foaming property of the emulsifier from being excessively large. More preferably, it is better to be 10 or less.

The polymerization initiator used in the emulsion polymerization is not particularly limited. For example, a persulfate-based initiator such as potassium persulfate or ammonium persulfate; a redox-based initiator such as persulfate (organic peroxide), persulfate/sulfite or the like.

The separation of the core-shell type graft copolymer of the polymer latex obtained by emulsion polymerization can be carried out by a conventional method such as a salting-out solidification method, a freeze-solidification method, and a spray drying method. Among these, from the viewpoint of easily removing impurities contained in the crosslinked rubber particle component by washing with water, the salting-out coagulation method and the freeze-solid method are preferred, and the freeze-solidification method is more preferable. In the freeze-solidification method, an acrylic resin film excellent in water resistance can be easily obtained without using a coagulant. Further, in order to remove the foreign matter mixed in the polymer latex before the solidification step, it is preferred to filter the polymer latex with a mesh of 50 μm or less. From the viewpoint of being easily dispersed uniformly in the melt kneading with the methacrylic resin [1], it is preferable to take the core-shell type graft copolymer as agglomerated particles of 1000 μm or less, and to extract it as agglomerated particles of 500 μm or less. . Further, the form of the agglomerated particles is not particularly limited. For example, the outermost layer may be in the form of particles in a state of being welded to each other, and may be a powdery or granular powder.

The elastomer component [2] used in the present invention can be used in combination with the above-mentioned block copolymer (B) and a core-shell graft copolymer.

Examples of the components other than the methacrylic resin [1] and the elastomer component [2] which may be contained in the acrylic film of the present invention include other polymers, fillers, antioxidants, thermal deterioration inhibitors, and ultraviolet absorption. Agents, light stabilizers, lubricants, mold release agents, polymer processing aids, antistatic agents, flame retardants, dyes and pigments, light diffusing agents, organic pigments, matting agents, impact modifiers and phosphors Additives such as. These may be added to either or both of the polymerization reaction liquids at the time of production of the methacrylic resin [1] or the elastomer component [2], or may be added to the methacrylic resin produced by the polymerization reaction [1]. Or any of the elastomer components [2] It may be added to the square or both, and may be added to the kneaded material of the methacrylic resin [1] or the elastomer component [2].

Examples of the other polymer include methacrylic resin other than methacrylic resin [1], polyethylene, polypropylene, polybutene-1, poly-4-methylpentene-1, polydecene, and the like. Polyolefin resin; ethylene ionomer; polystyrene, styrene-maleic anhydride copolymer, high impact polystyrene, AS resin, ABS resin, AES resin, AAS resin, ACS resin, MBS resin, etc. Ethylene resin; methyl methacrylate polymer, methyl methacrylate-styrene copolymer; polyester resin such as polyethylene terephthalate or polybutylene terephthalate; nylon 6, Polyamide, such as nylon 66, polyamide elastomer, polycarbonate, polyvinyl chloride, polyvinyl dichloride, polyvinyl alcohol, ethylene-vinyl alcohol copolymer, polyacetal, polydifluoroethylene, polyamine Formate, modified polyphenylene ether, polyphenylene sulfide, polyoxymethylene modified resin, polyvinyl butyral resin, polyethylene acetal resin; elastomer component other than elastomer component [2], Polyoxyethylene rubber; styrene-based thermoplastic elastomers such as SEPS, SEBS, SIS; olefins such as IR, EPR, and EPDM Such as plastic. The amount of the other polymer which may be contained in the methacrylic resin composition of the present invention is preferably 10 parts by mass or less based on 100 parts by mass of the total amount of the methacrylic resin [1] and the elastomer component [2]. .

A methacrylic resin composition according to a preferred embodiment of the present invention contains a polycarbonate resin, a phenoxy resin, a polyester resin, and a polyether in addition to the methacrylic resin [1] and the elastomer component [2]. Vinyl alcohol butyral resin, polyethylene acetal resin. By containing a polycarbonate resin, a phenoxy resin, a polyester resin, a polyvinyl butyral resin, Polyacetamide acetal resin can adjust the phase difference of the acrylic film. The amount of the polycarbonate resin, the phenoxy resin, the polyester resin, the polyvinyl butyral resin, and the polyethylene acetal resin is based on the total amount of the methacrylic resin [1] and the elastomer component [2]. The amount of 100 parts by mass is preferably from 1 to 10 parts by mass, more preferably from 2 to 7 parts by mass, even more preferably from 3 to 6 parts by mass.

The methacrylic resin composition of a further embodiment of the present invention contains a methacrylic resin [1], an elastomer component [2] and a polycarbonate resin. The polycarbonate resin used in the present invention is preferably an aromatic polycarbonate resin from the viewpoint of compatibility. The polycarbonate resin is a polymer obtained by a reaction of a polyfunctional hydroxy compound and a carbonate-forming compound. The amount of the polycarbonate resin is from 1 to 10 parts by mass based on 100 parts by mass of the total amount of the methacrylic resin [1] and the elastomer component [2], from the viewpoint that the phase difference of the molded article is small. Preferably, it is preferably 2 to 7 parts by mass, and more preferably 3 to 6 parts by mass.

The aromatic polycarbonate resin used in the present invention is not particularly limited depending on the method of production. For example, a phosgene method (interfacial polymerization method), a melt polymerization method (transesterification method), and the like can be mentioned. Further, the aromatic polycarbonate resin to be used in the present invention may be a post-treatment agent which is subjected to a polycarbonate resin produced by a melt polymerization method to adjust the amount of terminal hydroxyl groups.

The aromatic polycarbonate resin used in the present invention has a MVR value of 300 ° C and 1.2 kg, from the viewpoint of easily controlling a phase difference to a desired value and obtaining a molded article having excellent transparency. 80~400cm ³ /10 minutes is better, 100~300cm ³ /10 minutes is better, 130~250cm ³ /10 minutes is better, 150~230cm ³ /10 minutes is the best polycarbonate resin; Alternatively, the weight average molecular weight of the molecular weight converted to the standard polystyrene by the gel permeation chromatography (GPC) is preferably 13,000 to 32,000, more preferably 14,000 to 30,000, and even more preferably 15,000 to 28,000. The best polycarbonate resin is 18000~27000. The adjustment of the MVR value or molecular weight of the polycarbonate resin can be carried out by adjustment of an end terminator or a branching agent.

Examples of the filler include calcium carbonate, talc, carbon black, titanium oxide, cerium oxide, clay, barium sulfate, and magnesium carbonate. The amount of the filler which can be contained in the acrylic film of the present invention is preferably 3% by mass or less, more preferably 1.5% by mass or less.

The antioxidant is inherently effective in preventing oxidative degradation of the resin in the presence of oxygen. For example, a phosphorus-based antioxidant, a hindered phenol-based antioxidant, a thioether-based antioxidant, or the like can be given. These antioxidants may be used alone or in combination of two or more. Among them, a phosphorus-based antioxidant and a hindered phenol-based antioxidant are preferable from the viewpoint of preventing the effect of deterioration of optical properties due to coloring, and it is more preferable to use a phosphorus-based antioxidant together with a hindered phenol-based antioxidant. When a phosphorus-based antioxidant and a hindered phenol-based antioxidant are used in combination, the amount of the phosphorus-based antioxidant used: the amount of the hindered phenol-based antioxidant used is preferably 1:5 to 2:1 by mass ratio, and is 1 : 2~1:1 is better.

The phosphorus-based antioxidant is 2,2-methylenebis(4,6-di-t-butylphenyl)octylphosphite (manufactured by ADEKA Corporation; trade name: Adekastab HP-10), and reference (2, 4-Di-tert-butyl-phenyl) phosphite (manufactured by BASF Corporation; trade name: IRGAFOS 168) or the like is preferred.

The hindered phenolic antioxidant is neopentyl alcohol-tetra [3-(3,5- Di-tert-butyl-4-hydroxyphenyl)propionate] (manufactured by BASF Corporation; trade name: IRGANOX1010), octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl) Propionate (manufactured by BASF Corporation; trade name: IRGANOX 1076) is preferred.

The thermal deterioration inhibitor can prevent thermal deterioration of the resin by trapping polymer radicals generated when exposed to a high temperature in a substantially oxygen-free state. The thermal deterioration inhibitor is 2-tert-butyl-6-(3'-t-butyl-5'-methyl-hydroxybenzyl)-4-methylphenyl acrylate (manufactured by Sumitomo Chemical Co., Ltd.; Trade name: Sumilizcr GM), 2,4-di-p-pentyl-6-(3',5'-di-p-pentyl-2'-hydroxy-α-methylbenzyl)phenyl acrylate (Sumitomo Manufactured by a chemical company; trade name: Sumilizer GS).

The ultraviolet absorber is a compound having an ability to absorb ultraviolet rays. The ultraviolet absorber is mainly a compound having a function of converting light energy into heat energy. Examples of the ultraviolet absorber include diphenyl ketones, benzotriazoles, and trisole. Classes, benzoates, salicylates, cyanoacrylates, oxalic acid anilines, malonic esters, and formazan. These may be used alone or in combination of two or more. Among these, benzotriazoles, three The ultraviolet absorber having a maximum value εmax of the type or the wavelength of 380 to 450 nm is preferably 1200 dm ³ ‧ mol ^-1 cm ^-1 or less.

Since the benzotriazole has a high effect of suppressing the deterioration of optical characteristics such as coloring by ultraviolet irradiation, it is preferable to use the ultraviolet absorbing agent used when the methacrylic resin composition of the present invention is used in applications requiring such characteristics. The benzotriazole is 2-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)phenol (manufactured by BASF Corporation; trade name: TINUVIN329), 2-(2H-benzotriazol-2-yl)-4,6-bis(1-methyl-1-phenylethyl)phenol (manufactured by BASF Corporation; trade name: TINUVIN234), etc. .

Further, the ultraviolet absorber having a maximum value εmax of the Mohr absorption coefficient of 380 to 450 nm of 1200 dm ³ ‧ mol ^-1 cm ^-1 or less can suppress yellowing of the obtained molded body. Examples of such an ultraviolet absorber include 2-ethyl-2'-ethoxy-oxabenzidine (manufactured by Clariant Japan Co., Ltd.; trade name: Sandeyuboa VSU). Among these ultraviolet absorbers, benzotriazoles are suitable from the viewpoint of suppressing deterioration of the resin irradiated with ultraviolet rays.

Further, in order to effectively absorb a wavelength near a wavelength of 380 nm, a triazole-based ultraviolet absorber is suitable. Such a UV absorber may, for example, be 2,4,6-gin(2-hydroxy-4-hexyloxy-3-methylphenyl)-1,3,5-tri (Manufactured by ADEKA Corporation; LA-F70), 2,4-bis(2-hydroxy-4-butoxyphenyl)-6-2,4-bis(butoxyphenyl)-1,3,5- three Hydroxyphenyl three It is a UV absorber (manufactured by BASF Corporation; trade name: TINUVIN 460, TINUVIN 479).

In addition, in order to absorb light of a wavelength of 380 nm to 400 nm particularly effectively, WO 2011-089794, WO 2012-124395, JP-A-2012-012476, JP-A-2013-023461, JP-A-2013-112790, and JP-A are used. A metal complex containing a hetero-complex ring having a specific structure described in JP-A-2014-88542, JP-A-2014-88542, and JP-A-2014-88543 is preferably used as the ultraviolet absorber. The compound heterocyclic ring of a specific structure may, for example, be 2,2'-iminobisbenzoquinone or 2-(2-benzothiazolylamino)phenylhydrazine. Oxazole, 2-(2-benzothiazolylamino)benzimidazole, (2-benzoquinazolyl)(2-benzoimidazolyl)methane, bis(2-phenylhydrazine) Azolyl)methane, bis(2-benzothiazolyl)methane, bis[2-(N-substituted)benzimidazolyl]methane, and the like, and derivatives thereof. The central metal of such a metal complex is suitable for copper, nickel, cobalt and zinc. Further, the metal complex is preferably a user in a state in which the composition is dispersed in a medium (low molecular compound or polymer) for dispersing the metal complex.

The amount of the metal complex compound to be added is preferably 0.01 parts by mass to 5 parts by mass, based on 100 parts by mass of the total amount of the methacrylic resin [1] and the elastomer component [2] of the present invention. The mass parts are preferably 2 parts by mass. Since such a metal complex has a large molar absorption coefficient at a wavelength of 380 nm to 400 nm, the amount of addition can be reduced. Since the amount of addition can be reduced, deterioration of the appearance of a molded article such as a film due to bleeding can be suppressed. Further, since the heat resistance is high, deterioration and decomposition at the time of molding processing are small, and the light resistance is high, so that the performance can be maintained for a long period of time.

Further, the maximum value εmax of the molar absorption coefficient of the ultraviolet absorber was measured as follows. To the 1 L of cyclohexane, 10.00 mg of an ultraviolet absorber was added, and it was dissolved by visually observing the absence of undissolved matter. This solution was poured into a quartz glass tank of 1 cm × 1 cm × 3 cm, and the absorbance at a wavelength of 380 nm to 450 nm was measured using a U-3410 spectrophotometer manufactured by Hitachi, Ltd. The molecular weight (MUV) of the ultraviolet absorber and the maximum value (Amax) of the measured absorbance were calculated by the following formula, and the maximum value εmax of the molar absorption coefficient was obtained.

Εmax=[Amax/(10×10 ^-3 )]×MUV

Light stabilizers are mainly produced by trapping and passing light and oxidizing a compound of free radical function. A preferred light stabilizer is a hindered amine such as a compound having a 2,2,6,6-tetraalkylpiperidine skeleton.

Examples of the lubricant include stearic acid, diced acid, stearylamine, methylenebisstearylamine, hydroxystearic acid triglyceride, paraffin wax, ketone wax, octanol, and hardened oil.

Examples of the release agent include higher alcohols such as cetyl alcohol and stearyl alcohol; glycerin higher fatty acid esters such as stearic acid monoglyceride and stearic acid diglyceride. In the present invention, the release agent is preferably a combination of a higher alcohol and a glycerin fatty acid monoester. When a higher alcohol and a glycerin fatty acid monoester are used in combination, the ratio thereof is not particularly limited, but the amount of the higher alcohol used: the amount of the glycerin fatty acid monoester used, in terms of mass ratio, is 2.5:1 to 3.5:1. Good, better with 2.8:1~3.2:1.

The polymer processing aid is usually a polymer particle having a particle diameter of 0.05 to 0.5 μm which can be produced by an emulsion polymerization method. The polymer particles may be a single layer of particles composed of a single composition ratio and a single ultimate viscosity polymer, and may be a multilayer particle composed of two or more kinds of polymers having different composition ratios or ultimate viscosity. Among these, a polymer layer having a low viscosity at the inner layer and a two-layer structure particle having a polymer layer having a high ultimate viscosity of 5 dl/g or more are preferable. It is preferred that the polymer processing aid has an ultimate viscosity of 3 to 6 dl/g. When the ultimate viscosity is too small, the effect of improving the formability tends to be low. When the ultimate viscosity is too large, the formability of the methacrylic resin composition tends to be lowered.

The organic dye is preferably a compound having a function of converting ultraviolet rays into visible light.

Examples of the light diffusing agent and the matting agent include glass fine particles, polyoxyalkylene-based crosslinked fine particles, crosslinked polymer fine particles, talc, calcium carbonate, and barium sulfate.

Examples of the fluorescent system include fluorescent pigments, fluorescent dyes, fluorescent white dyes, fluorescent whitening agents, and fluorescent bleaching agents.

Antioxidant, thermal deterioration inhibitor, ultraviolet absorber, light stabilizer, lubricant, mold release agent, polymer processing aid, antistatic agent, flame retardant, dye and pigment which may be contained in the acrylic film of the present invention The total amount of the light diffusing agent, the organic dye, the matting agent, the impact modifier, and the phosphor is preferably 7% by mass or less, more preferably 5% by mass or less, and still more preferably 4% by mass or less.

The method for producing the methacrylic resin composition constituting the acrylic film of the present invention is not particularly limited. For example, a methacrylic resin composition can be produced by melt-kneading a methacrylic resin [1] and an elastomer component [2] with another polymer such as a polycarbonate resin. The melt kneading system can be carried out using, for example, a kneader-ruder, an extruder, a mixing roll, a Banbury mixer or the like. The temperature at the time of kneading can be appropriately adjusted according to the softening temperature of the methacrylic resin [1], the elastomer component [2], and other polymers, and is generally kneaded at a temperature in the range of 150 ° C to 300 ° C.

Another method for producing a methacrylic resin composition is to produce a methacrylic resin by polymerizing a monomer of a raw material of the elastomer component [2] in the presence of a methacrylic resin [1] and other polymers. The method of things. This polymerization can be carried out in the same manner as the polymerization method for producing the methacrylic resin [2]. In methacrylic resin [1] And a method for polymerizing a monomer of a raw material of the elastomer component [2] in the presence of another polymer, and melting and kneading the methacrylic resin [1], the elastomer component [2], and other polymers. In the method of production, since the thermal history of the methacrylic resin is shortened, the thermal decomposition of the methacrylic resin is suppressed, and a molded article having less coloration and foreign matter is easily obtained.

The acrylic film of the present invention can be produced by a solution casting method, a melt casting method, an extrusion molding method, an inflation molding method, a blow molding method, or the like. Among these, from the viewpoint of obtaining a film having excellent transparency, improved toughness, excellent handleability, and excellent balance between toughness and surface hardness and rigidity, an extrusion molding method is preferred. The temperature of the methacrylic resin composition discharged from the extruder is preferably 200 to 300 ° C, more preferably 250 to 280 ° C.

Among the extrusion molding methods, from the viewpoint of obtaining a film having good surface smoothness, good specular gloss, and low haze, the methacrylic resin composition is extruded from a T die in a molten state, and then this is A method of forming by sandwiching two or more mirror rolls or mirror belts or a combination thereof is preferred.

The mirror roll is preferably a metal elastic roll having a mirror-like film in a general metal rigid roll or an outer tube. The line pressure between the pair of mirror rollers or the mirror belt is preferably 2 to 100 N/mm, more preferably 10 to 60 N/mm, and even more preferably 25 to 45 N/mm. When it is less than 2N/mm, it is not good due to insufficient transfer of the mirror surface. On the other hand, when it is 100 N/mm or more, the stress remaining on the film is large and it is easy to thermally shrink, which is not preferable.

Moreover, the surface temperature of a pair of mirror rollers or mirror belts It is preferably from 50 ° C to 130 ° C, and more preferably from 60 ° C to 100 ° C. When such a surface temperature is set, the methacrylic resin composition discharged from the extruder can be cooled at a faster rate than natural cooling, and a film having excellent surface smoothness and low haze can be easily produced. The thickness of the unstretched film obtained by extrusion molding is preferably from 10 to 300 μm, more preferably from 15 to 100 μm. The haze of the film is generally 1.0% or less, preferably 0.5% or less, more preferably 0.3% or less.

The acrylic film of the present invention can be subjected to an extension treatment after forming a film. By increasing the mechanical strength by the stretching treatment, a film which is not easily cracked can be obtained. The stretching method is not particularly limited, and examples thereof include a simultaneous biaxial stretching method, a sequential biaxial stretching method, and a tubular stretching method. From the viewpoint of being able to uniformly extend to obtain a high-strength film, the lower temperature limit at the time of stretching is a temperature higher than the glass transition temperature of the methacrylic resin composition by 10 ° C, and the upper limit of temperature at the time of stretching is a ratio of the methacrylic resin composition. The glass transition temperature is 40 ° C higher. The extension is generally carried out at 100 to 5000%/min. After the stretching, a film having less heat shrinkage can be obtained by heat setting. The film thickness after stretching is preferably from 10 to 200 μm.

Further, the acrylic film of the present invention can be subjected to treatments such as easy adhesion treatment, hard coat treatment, and knurling processing.

Since the acrylic film of the present invention has high transparency and heat resistance, it is suitable for use in optical applications, and is particularly suitable for a polarizer protective film, a liquid crystal protective sheet, a surface material of a portable information terminal, and a display window protection of a portable information terminal. A thin film, a light guiding film, a transparent conductive film coated with a silver nanowire or a carbon nanotube, and a panel for various displays. In particular, the film of the present invention comprising a methacrylic resin composition comprising a methacrylic resin and a polycarbonate resin can be applied to an optical use such as a polarizer protective film or a retardation film, by imparting a desired phase difference. Since the film of the present invention has high transparency and heat resistance, it can be used as an infrared cut film, an anti-theft film, a shatterproof film, a decorative film, a metal decorative film, a back sheet of a solar cell, or the like for applications other than optical use. A panel for a flexible solar cell, a shrink film, and a film for an in-mold label.

[Examples]

Hereinafter, the present invention will be specifically described based on examples and comparative examples, but the present invention is not limited to the following examples. Further, the measurement of the physical property value or the like is carried out by the following method.

(polymerization conversion rate)

Gas chromatograph GC-14A manufactured by Shimadzu Corporation was connected to InertCap1 (df = 0.4 μm, 0.25 mm I.D. × 60 m) manufactured by GL Sciences Inc. as a column, and heated to 180 ° C at an injection temperature. The temperature was raised to 180 ° C, and the column temperature was measured from 60 ° C (for 5 minutes) at a temperature increase rate of 10 ° C /min to 200 ° C for 10 minutes, and the polymerization conversion ratio was calculated from the results.

(Mw, molecular weight distribution)

Mw and molecular weight distribution were measured by a gel permeation chromatography (GPC) under the following conditions to obtain a value converted to the molecular weight of standard polystyrene.

GPC device: HLC-8320 manufactured by Tosoh Corporation

Detector: differential refractive index detector

Pipe column: manufactured by 2 Dongcao Co., Ltd. TSKgel SuperMultipore HZMM is connected in series with SuperHZ4000.

Eluent: tetrahydrofuran

Eluent flow rate: 0.35ml/min

Column temperature: 40 ° C

Standard curve: Draw data using standard polystyrene 10 points

(Triple shows the degree of agreement (rr))

The methacrylic resin obtained in each of the production examples was subjected to 1H-NMR measurement. The area (X) of 0.6 to 0.95 ppm and the area (Y) of 0.6 to 1.35 ppm when TMS is 0 ppm are measured, and the value calculated by the formula: (X/Y) × 100 is used as a triplet display. Rule (rr) (%).

Device: Nuclear Magnetic Resonance Device (manufactured by Bruker; ULTRA SHIELD 400PLUS)

Solvent: deuterated chloroform

Measuring nuclear species: 1H

Measuring temperature: room temperature

Cumulative number: 64 times

(glass transition temperature)

The methacrylic resin obtained in each of the production examples was subjected to a differential scanning calorimeter (manufactured by Shimadzu Corporation; DSC-50 (product number)) according to JIS K7121. The temperature was once raised to 230 ° C, and then cooled to room temperature, and then, The DSC curve was measured at a temperature of from room temperature to 230 ° C at 10 ° C /min. The intermediate point glass transition temperature obtained from the DSC curve measured at the second temperature rise is taken as the glass transition temperature of the present invention.

(thickness measurement)

The thickness measurement of the acrylic film was measured using a microgauge.

(the size of the dispersed phase (elastomer dispersed phase) derived from the elastomer component)

Determined by phosphotungstic acid staining. The sheets used in the two measurements were prepared in the following manner. The sheet A was obtained by using a microtome in the thickness direction of the film and in the extrusion direction of the film. The sheet B was obtained by using a microtome in the thickness direction of the film and in a direction perpendicular to the extrusion direction.

Next, the sheets A and B were respectively immersed in a phosphotungstic acid solution (manufactured by TABB Co., Ltd.; PHOSPHOTUNGSTATEACIDEM) (15% by mass, ion-exchanged water: 2% by mass, and 83% by mass of methanol) for dyeing for 15 minutes, and were subjected to transmission electron microscopy (Japan). Manufactured by an electronics company; JSM-7600) was observed at an acceleration voltage of 25 kV and a magnification of 30000-100000.

In the sheet A, 100 dispersed phases dyed in the extrusion direction of the film were taken, and the long axis average was taken to obtain the long axis average value (A-Av).

In the sheet B, 100 dispersed phases which were dyed in the direction perpendicular to the extrusion direction of the film were taken, and the average of the long axes was taken to obtain the long-axis average value (B-Av).

The larger of the long axis average (A-Av) and the long axis average (B-Av) is the long axis derived from the dispersed phase of the elastomer component [2].

(pencil hardness)

The acrylic film was measured in accordance with JIS K5600-5-4.

(punching)

The acrylic film was drilled with a punch and the following evaluation was performed with the naked eye.

○: Good.

△: A slight gap appears.

×: A crack is generated from the punched portion.

(bending whitening)

The acrylic film was bent 180 degrees and the degree of whitening was evaluated by the naked eye by the following.

○: No whitening.

△: It is slightly whitened.

×: Whitening is remarkable.

-: The bend is broken.

(drug resistance)

The drug system is isopropyl alcohol (manufactured by Wako Pure Chemical Industries, Ltd.; first-grade reagent: IPA for short) and xylene (manufactured by Wako Pure Chemical Industries, Ltd.; primary reagent), and the following method (Drip-in method) of JIS K5600-6-1 Evaluation.

○: There is no change in appearance.

△: A little whitening.

×: Significant whitening or dissolution and residual marks.

Manufacturing example 1

[Synthesis of methacrylic resin [A-1]]

A 5 m ³ reaction vessel made of a glass lining equipped with a brine-coolable jacket and a stirrer was replaced with nitrogen. Here, 1600 kg of toluene, 3.19 kg of 1,1,4,7,10,10-hexamethyltriethylenetetramine (13.9 m), and isobutyl bis of 0.45 M were fed at room temperature (2, 68.6 g (39.6 mol) of a toluene solution of 6-di-tertiary butyl-4-methylphenoxy)aluminum and a solution of a secondary butyllithium having a concentration of 1.3 M (solvent: 95% by mass of cyclohexane, N-hexane 5 mass%) 7.91 kg (13.2 mol). While stirring, while maintaining 20 ° C, it took 30 minutes to drip 550 kg of distilled methyl methacrylate. After the completion of the dropwise addition, the mixture was stirred at 20 ° C for 90 minutes. The color of the solution changes from yellow to colorless. At this point, the polymerization conversion ratio of methyl methacrylate was 100%.

To the resulting solution, 1500 kg of toluene was added and diluted. Next, the diluted solution was poured into a large amount of methanol to obtain a precipitate. The obtained precipitate was dried at 80 ° C and 140 Pa for 24 hours to obtain Mw of 58900, molecular weight distribution of 1.06, ternary group showing a degree of (rr) of 74%, glass transition temperature of 130 ° C, and derived from A. The proportion of the constituent unit of the methyl acrylate is 100% by mass of the methacrylic resin [A-1].

Manufacturing Example 2

[Synthesis of methacrylic resin [A-2]]

A 5 m ³ reaction vessel made of a glass lining equipped with a brine-coolable jacket and a stirrer was replaced with nitrogen. Here, 1600 kg of toluene, 2.49 kg of 1,1,4,7,10,10-hexamethyltriethylenetetramine (10.8 mol), and isobutyl bis of 0.45 M were fed at room temperature. 53.5 kg (30.9 mol) of a toluene solution of 6-di-tris-butyl-4-methylphenoxy)aluminum and a solution of a secondary butyllithium having a concentration of 1.3 M (solvent: 95% by mass of cyclohexane, N-hexane 5 mass%) 6.17 kg (10.3 mol). While stirring, 550 kg of distilled methyl methacrylate was dropped into the mixture while maintaining the temperature at 20 ° C for 30 minutes. After the completion of the dropwise addition, the mixture was stirred at 20 ° C for 90 minutes. The color of the solution changes from yellow to colorless. At this point, the polymerization conversion ratio of methyl methacrylate was 100%.

To the resulting solution, 1500 kg of toluene was added and diluted. Next, the diluted solution was poured into a large amount of methanol to obtain a precipitate. Sink The precipitate was dried at 80 ° C, 140 Pa for 24 hours to obtain a Mw of 81,400, a molecular weight distribution of 1.08, a ternary group showing a rule (rr) of 73%, a glass transition temperature of 131 ° C, and a source of methacrylic acid. The ratio of the constituent units of the methyl ester was 100% by mass of methacrylic resin [A-2].

Manufacturing Example 3

[Synthesis of methacrylic resin [A-3]]

A 5 m ³ reaction vessel made of a glass lining equipped with a brine-coolable jacket and a stirrer was replaced with nitrogen. Here, 1600 kg of toluene, 2.49 kg of 1,1,4,7,10,10-hexamethyltriethylenetetramine (10.8 mol), and isobutyl bis of 0.45 M were fed at room temperature. 53.5 kg (30.9 mol) of a toluene solution of 6-di-tris-butyl-4-methylphenoxy)aluminum and a solution of a secondary butyllithium having a concentration of 1.3 M (solvent: 95% by mass of cyclohexane, N-hexane 5 mass%) 6.17 kg (10.3 mol). While stirring, 550 kg of distilled methyl methacrylate was added dropwise thereto while maintaining the temperature at -20 ° C for 30 minutes. After the completion of the dropwise addition, the mixture was stirred at -20 ° C for 180 minutes. The color of the solution changed from yellow to colorless. At this point, the polymerization conversion ratio of methyl methacrylate was 100%.

To the resulting solution, 1500 kg of toluene was added and diluted. Next, the diluted solution was poured into a large amount of methanol to obtain a precipitate. The obtained precipitate was dried at 80 ° C and 140 Pa for 24 hours to obtain Mw of 96100, a molecular weight distribution of 1.07, a ternary group showing a degree of (rr) of 83%, a glass transition temperature of 133 ° C, and a The proportion of the constituent unit of the methyl acrylate is 100% by mass of the methacrylic resin [A-3].

Manufacturing Example 4

[Synthesis of methacrylic resin [A-4]]

The inside of the autoclave equipped with a stirrer and a sampling tube was replaced with nitrogen. Here, 100 parts by mass of purified methyl methacrylate and 2,2'-azobis(2-methylpropionitrile (hydrogen-recovering function: 1%, 1 hour half-life temperature: 83 ° C) 0.0052 mass are fed. The fraction and 0.28 parts by mass of n-octyl mercaptan were stirred to obtain a raw material liquid, and nitrogen was fed into the raw material liquid to remove dissolved oxygen in the raw material liquid.

The raw material liquid was fed to a tank type reactor connected to the autoclave to 2/3 of the capacity. The temperature was maintained at 140 ° C and the polymerization was first started in batch mode. When the polymerization conversion ratio is 55 mass%, the raw material liquid is supplied from the autoclave to the tank reactor at a flow rate of an average residence time of 150 minutes, and the raw material liquid is discharged from the tank type at a flow rate corresponding to the supply flow rate of the raw material liquid. The reactor was extracted and maintained at a temperature of 140 ° C, switching to a continuous flow mode of polymerization. After the switching, the polymerization conversion rate in the steady state was 55 mass%.

The reaction liquid taken out from the tank reactor which was in a stable state was supplied to a multi-tube heat exchanger having an internal temperature of 230 ° C at a flow rate of 2 minutes on average to increase the temperature. Then, the warmed reaction liquid is introduced into a flash evaporator, and volatile matter containing unreacted monomers as a main component is removed to obtain a molten resin. The molten resin from which the volatile matter was removed was supplied to a biaxial extruder having an internal temperature of 260 ° C to be discharged into a strand shape, and then cut by a pelletizer to obtain a granular Mw of 82,000, a molecular weight distribution of 1.85, and a ternary display. The methacrylic resin [A-4] having a constitution (rr) of 52%, a glass transition temperature of 120 ° C, and a content of a constituent unit derived from methyl methacrylate of 100% by mass.

The obtained methacrylic resin [A-1] to [A-4] is as follows.

Manufacturing Example 5

[Synthesis of Block Copolymer (B-1)]

735 kg of dry toluene and 0.4 kg of hexamethyltriethylenetetramine were added to a 3 m ³ reaction vessel made of a glass lining equipped with a brine-coolable jacket and a stirrer, which was degassed and replaced with nitrogen. And isobutyl bis(2,6-di-tert-butyl-4-methylphenoxy)aluminum 20 mol of toluene solution 39.4 kg, further added to the secondary butyl lithium 1.17 mol. Here, 35.0 kg of methyl methacrylate was added, and the mixture was reacted at room temperature for 1 hour. The polymer contained in the reaction liquid was sampled, and the weight average molecular weight (hereinafter referred to as Mw (b1-1)) was measured to be 40,000. When the methyl methacrylate polymer is further subjected to block copolymerization with an acrylate, the methyl methacrylate polymer becomes a methacrylate polymer block (b1) (hereinafter referred to as "methyl methacrylate polymer" Block (b1-1)").

Next, while maintaining the reaction liquid at -25 ° C, 35 kg of n-butyl acrylate was dropped over 0.5 hours. Immediately after the dropwise addition, the polymer contained in the reaction liquid was sampled, and the weight average molecular weight was determined to be 80,000. Since the weight average molecular weight of the methyl methacrylate polymer block (b1-1) is 40,000, the weight average molecular weight (Mw (b2)) of the acrylate polymer block (b2) containing n-butyl acrylate is determined as 40,000.

Next, 35.0 kg of methyl methacrylate was added, and the reaction liquid was returned to room temperature, and stirred for 8 hours to form a second methacrylate polymer block (b1) (hereinafter referred to as "methyl methacrylate polymerization". Block (b1-2)"). Then, 4 kg of methanol was added to the reaction liquid to stop the polymerization, and then the reaction liquid was poured into a large amount of methanol to form a block copolymer (B) of a triblock copolymer (hereinafter referred to as "block copolymer (B-). 1)") was separated, filtered, and dried by drying at 80 ° C, 1 Torr (about 133 Pa) for 12 hours. The weight average molecular weight Mw (B) of the obtained block copolymer (B-1) was 120,000. Since the weight average molecular weight of the diblock copolymer was 80,000, the weight average molecular weight (Mw (b1-2)) of the methyl methacrylate polymer block (b1-2) was determined to be 40,000. The weight average molecular weight Mw (b1-1) of the methyl methacrylate polymer block (b1-1) and the weight average molecular weight Mw of the methyl methacrylate polymer block (b1-2) (b1-2) ) are 40,000, so Mw (b1) is 40,000. The content of the acrylate in the block copolymer was 33%.

Manufacturing Example 6

[Synthesis of Block Copolymer (B-2)]

Inside degassed and purged with nitrogen with the inner 3m ³ glass lining reaction vessel may be made of brine-cooled jacket of the stirrer and, at room temperature was added dry toluene containing 735kg, hexamethyl triethylenetetramine 0.4kg And isobutyl bis(2,6-di-tert-butyl-4-methylphenoxy)aluminum 20 mol of toluene solution 39.4 kg, further added to the secondary butyl lithium 1.17 mol. Here, 35.0 kg of methyl methacrylate was added, and the mixture was reacted at room temperature for 1 hour. The polymer contained in the reaction liquid was sampled, and the weight average molecular weight (hereinafter referred to as Mw (b1-1)) was measured to be 40,000. When the methyl methacrylate polymer is further subjected to block copolymerization with an acrylate, the methyl methacrylate polymer becomes a methacrylate polymer block (b1) (hereinafter referred to as "methyl methacrylate polymer" Block (b1-1)").

Next, while maintaining the reaction liquid at -25 ° C, a mixed liquid of 24.5 kg of n-butyl acrylate and 10.5 kg of benzyl acrylate was added dropwise over 0.5 hours. Immediately after the dropwise addition, the polymer contained in the reaction liquid was sampled, and the weight average molecular weight was determined to be 80,000. Since the weight average molecular weight of the methyl methacrylate polymer block (b1-1) is 40,000, the weight average molecular weight of the acrylate polymer block (b2) comprising a copolymer of n-butyl acrylate and benzyl acrylate ( Mw (b2)) was determined to be 40,000. The content of the acrylate in the block copolymer was 50%.

Manufacturing Example 7

[Synthesis of core-shell graft copolymer (B-3)]

(1) feeding 1050 parts by mass of ion-exchanged water and 0.6 parts by mass of polyoxyethylene tridecyl ether acetate in a reactor equipped with a stirrer, a thermometer, a nitrogen introduction tube, a monomer introduction tube, and a reflux condenser; 0.7 parts by mass of sodium carbonate was sufficiently replaced in the reactor with nitrogen. Next, the internal temperature was made 80 °C. Here, 0.25 parts by mass of potassium persulfate was added, followed by stirring for 5 minutes. Thereto, 245 parts by mass of a monomer mixture containing 95.4% by mass of methyl methacrylate, 4.4% by mass of methyl acrylate, and 0.2% by mass of allyl methacrylate was continuously dropped over 60 minutes. After the completion of the dropwise addition, the polymerization reaction was further carried out for 30 minutes so that the polymerization conversion ratio became 98% or more.

(2) Next, 0.32 parts by mass of potassium persulfate was placed in the same reactor and stirred for 5 minutes. Then, 80.5% by mass of butyl acrylate, 17.5% by mass of styrene, and 2 mass of allyl methacrylate were continuously dropped in 60 minutes. 5% by mass of a monomer mixture of %. After the completion of the dropwise addition, the polymerization reaction was further carried out for 30 minutes so that the polymerization conversion ratio became 98% or more.

(3) Next, 0.14 parts by mass of potassium persulfate was introduced into the reactor and stirred for 5 minutes. Then, 140 parts by mass of a monomer mixture containing 95.2% by mass of methyl methacrylate, 4.4% by mass of methyl acrylate and 0.4% by mass of n-octyl mercaptan was continuously added dropwise over 30 minutes. After the completion of the dropwise addition, the polymerization reaction was further carried out for 60 minutes so that the polymerization conversion ratio became 98% or more. By the above operation, a latex containing the crosslinked rubber particles (A1) was obtained. The latex containing the crosslinked rubber particles (A1) is frozen and solidified. Subsequently, it was washed with water and dried to obtain a core-shell type graft copolymer. The graft copolymer had an average particle diameter of 0.09 μm. Further, the content of the acrylate in the core-shell type graft copolymer was 39%.

Manufacturing Example 8

[Synthesis of core-shell graft copolymer (B-4)]

(1) feeding 1050 parts by mass of ion-exchanged water and 0.1 parts by mass of sodium polyoxyethylene tridecyl ether acetate in a reactor equipped with a stirrer, a thermometer, a nitrogen introduction tube, a monomer introduction tube, and a reflux condenser; 0.7 parts by mass of sodium carbonate was sufficiently replaced in the reactor with nitrogen. Next, the internal temperature was made 80 °C. Here, 0.25 parts by mass of potassium persulfate was added, followed by stirring for 5 minutes. Thereto, 245 parts by mass of a monomer mixture containing 95.4% by mass of methyl methacrylate, 4.4% by mass of methyl acrylate, and 0.2% by mass of allyl methacrylate was continuously dropped over 60 minutes. After the completion of the dropwise addition, the polymerization reaction was further carried out for 30 minutes so that the polymerization conversion ratio became 98% or more.

(2) Next, 0.32 parts by mass of potassium persulfate was placed in the same reactor and stirred for 5 minutes. Then, continuously instilling butyl acrylate in 60 minutes 315 parts by mass of a monomer mixture of 80.5 mass%, styrene 17.5% by mass, and methacrylic acid allyl ester 2 mass%. After the completion of the dropwise addition, the polymerization reaction was further carried out for 30 minutes so that the polymerization conversion ratio became 98% or more.

(3) Next, 0.14 parts by mass of potassium persulfate was introduced into the reactor and stirred for 5 minutes. Then, 140 parts by mass of a monomer mixture containing 95.2% by mass of methyl methacrylate, 4.4% by mass of methyl acrylate and 0.4% by mass of n-octyl mercaptan was continuously added dropwise over 30 minutes. After the completion of the dropwise addition, the polymerization reaction was further carried out for 60 minutes so that the polymerization conversion ratio became 98% or more. By the above operation, a latex containing the crosslinked rubber particles (A1) was obtained. The latex containing the crosslinked rubber particles (A1) is frozen and solidified. Subsequently, it was washed with water and dried to obtain a core-shell type graft copolymer. The graft copolymer had an average particle diameter of 0.35 μm. Further, the content of the acrylate in the core-shell type graft copolymer was 39%.

[Synthesis of core-shell graft copolymer (B-5)]

(1) feeding 1050 parts by mass of ion-exchanged water and 1.0 part by mass of polyoxyethylene tridecyl ether acetate in a reactor equipped with a stirrer, a thermometer, a nitrogen introduction tube, a monomer introduction tube, and a reflux condenser; 0.7 parts by mass of sodium carbonate was sufficiently replaced in the reactor with nitrogen. Next, the internal temperature was made 80 °C. Here, 0.25 parts by mass of potassium persulfate was added, followed by stirring for 5 minutes. Among them, 445 parts by mass of a monomer mixture containing 95.4% by mass of methyl methacrylate, 4.4% by mass of methyl acrylate, and 0.2% by mass of allyl methacrylate was continuously dropped over 60 minutes. After the completion of the dropwise addition, the polymerization reaction was further carried out for 30 minutes so that the polymerization conversion ratio became 98% or more.

(2) Next, 0.32 parts by mass of potassium persulfate was placed in the same reactor and stirred for 5 minutes. Then, continuously instilling butyl acrylate in 60 minutes 115 parts by mass of a monomer mixture of 80.5 mass%, styrene 17.5% by mass, and methacrylic acid allyl ester 2 mass%. After the completion of the dropwise addition, the polymerization reaction was further carried out for 30 minutes so that the polymerization conversion ratio became 98% or more.

(3) Next, 0.14 parts by mass of potassium persulfate was introduced into the reactor and stirred for 5 minutes. Then, 140 parts by mass of a monomer mixture containing 95.2% by mass of methyl methacrylate, 4.4% by mass of methyl acrylate and 0.4% by mass of n-octyl mercaptan was continuously added dropwise over 30 minutes. After the completion of the dropwise addition, the polymerization reaction was further carried out for 60 minutes so that the polymerization conversion ratio became 98% or more. By the above operation, a latex containing the crosslinked rubber particles (A1) was obtained. The latex containing the crosslinked rubber particles (A1) is frozen and solidified. Subsequently, it was washed with water and dried to obtain a core-shell type graft copolymer. The graft copolymer had an average particle diameter of 0.09 μm. Further, the content of the acrylate in the core-shell type graft copolymer was 17%.

The obtained elastomer component and (B-1) to (B-5) are shown below.

The following applies to the ultraviolet absorber.

D-1: UV absorber ATNUVIN460 manufactured by BASF

D-2: BASF UV absorbers TINUVIN479

<Example 1>

85 parts by mass of methacrylic resin [A-1], 15 parts by mass of block copolymer (B-1), and 1 part by mass of ultraviolet absorber [D-1] were mixed in a tumbler at 250 ° C in two-axis The extruder (Toshiba Machine Co., Ltd. TEM-41SS) was extruded at a set temperature of 250 ° C to produce a methacrylic resin composition.

The methacrylic acid composition was melt-extruded in a 65φmm single-axis extruder having a T-die at a cylinder temperature of 250 ° C and a die temperature of 260 ° C to set a metal elastic roller of 80 ° C and set to 80 ° C. The metal rigid roller was held to produce a film having a thickness of 40 μm. The results of this evaluation are shown in Table 3.

<Examples 2 to 6>

The same procedure as in Example 1 was carried out in the same manner as in Example 1 to prepare a methacrylic resin composition, and a film of each thickness was obtained under the same temperature conditions as in Example 1. The results are summarized in Table 3.

<Comparative Examples 1 to 6>

The same procedure as in Example 1 was carried out in the same manner as in Example 1 to prepare a methacrylic resin composition, and a film of each thickness was obtained by using the same apparatus as in Example 1. The results are summarized in Table 4.

From the above results, it was found that the film having a range exceeding the range specified by the acrylic film of the present invention was inferior in pencil hardness and chemical resistance (Comparative Example 1), punching property, and inferior bending whitening (Comparative Examples 2, 3, and 6). The glass transition temperature was lowered and the resistance to p-xylene was lowered (Comparative Examples 4 and 5).

<Examples 7 to 11>

The same operation as in Example 1 was carried out in the formulation shown in Table 5, and the manufacturing was carried out. A film of 80 μm was produced in the same manner as in Example 1 for the methacrylic resin composition. Then, the film was heated at 140 ° C and biaxially stretched in a widthwise manner by a tenter method to obtain a film of 20 μm. The evaluation results of the obtained film are shown in Table 5.

It can be seen from Examples 7 to 11 that when the film is biaxially stretched, the amount of the elastomer component is small, the punching property is good, and the pencil hardness is high. The rigidity is high, and the surface hardness is also high.

<Example 12>

The same composition as in Example 7, and further adding 100 parts by mass of the polycarbonate Iupilon manufactured by Mitsubishi Engineering Plastics Co., Ltd. with respect to the methacrylic resin [A-1] and the block copolymer (B-3) 6 parts by weight of HL-8000 was melt-kneaded to prepare a methacrylic resin composition [C-1], and a film of 80 μm was produced in the same manner as in Example 7. Then, the film was heated at 140 ° C and biaxially stretched in a widthwise manner by a tenter method to obtain a film of 20 μm.

As a result of evaluation of the obtained film, the size of the dispersed phase of the elastomer was 250 nm, the punch hardness of the pencil hardness was ○, the whitening of the bend was ○, and the resistance to IPA and xylene was ○.

<Example 13>

The polycarbonate was used in the same manner as in Example 12 except that SDPOLYCATR-2000 manufactured by Sumika Styron Polycarbonate Co., Ltd. was used in place of the polycarbonate Iupilon HL-8000 manufactured by Mitsubishi Engineering Plastics Co., Ltd., except that the amount thereof was 4 parts by weight. The methacrylic resin composition (C-2) was produced, and a film of 20 μm was produced in the same manner as in Example 12. As a result of evaluation of the obtained film, the size of the dispersed phase of the elastomer was 250 nm, the punch hardness of the pencil hardness was ○, the whitening of the bend was ○, and the resistance to IPA and xylene was ○.

From the above results, it is understood that the methacrylic resin [1] and the elastomer component [2] having a gradation (rr) of 65% or more in the triad display have a mass ratio of 60/99 to 40/1 ( a methacrylic resin composition of methacrylic resin [1] / elastomer component [2]), by blending a polycarbonate tree The fat can also obtain a film having excellent glass transition temperature, pencil hardness, punching property, bending whitening, and chemical resistance.

Claims (13)

An acrylic film comprising a ternary group having a mass ratio of 60/40 to 99/1 in a ratio of a methacrylic resin [1]/elastomer component [2] to a scale (rr) of 65 An acrylic film having a methacrylic resin [1] or more and a methacrylic resin composition containing an elastomer component [2] derived from 30% by mass or more of a structural unit derived from an acrylate, characterized in that the acrylic film is When the sheet is dyed with phosphotungstic acid, the long axis of the dispersed phase derived from the elastomer component [2] is from 10 to 300 nm. The acrylic film according to claim 1, wherein the methacrylic resin [1] has a molecular weight distribution of 1.5 or less. The acrylic film according to claim 1 or 2, wherein the mass ratio of the methacrylic resin [1] / elastomer component [2] is from 80/20 to 99/1. The acrylic film according to any one of claims 1 to 3, wherein the elastomer component [2] contains a polymer (b1) comprising a structural unit having a methacrylate as a main component, and having an acrylate. A block copolymer of a combination of polymers (b2) of structural units. The acrylic film according to any one of claims 1 to 4, wherein the elastomer component [2] contains a core-shell type graft copolymer. The acrylic film according to any one of claims 1 to 5, wherein the methacrylic resin composition further contains an ultraviolet absorber. The acrylic film according to any one of claims 1 to 6, wherein the methacrylic resin composition is further 100 parts by mass based on the total amount of the methacrylic resin [1] and the elastomer component [2]. It contains 1 to 10 parts by mass of a polycarbonate resin. A laminated film using the same according to any one of claims 1 to 7 An olefinic film. A polarizer protective film comprising the acrylic film according to any one of claims 1 to 7. A method for producing an acrylic film, which is obtained by melt-kneading a triplet between the methacrylic resin [1]/elastomer component [2] at a mass ratio of 60/40 to 99/1 (rr) 65% or more of the methacrylic resin [1] and the elastomer component [2] containing 30% by mass or more of the structural unit derived from the acrylate, the methacrylic resin composition is obtained, and the methacrylic resin composition is further obtained. A method for producing a formed acrylic film, wherein the longitudinal direction of the dispersed phase derived from the elastomer component [2] when the sheet of the acrylic film is dyed with phosphotungstic acid is 10 to 300 nm. The method for producing an acrylic film according to claim 10, wherein the acrylic film is further extended. The method for producing an acrylic film according to claim 10 or 11, which further comprises melt-kneading the polycarbonate resin to obtain the methacrylic resin composition. The method for producing an acrylic film according to any one of claims 10 to 12, wherein the step of polymerizing a monomer constituting the polymer (b1) having a structural unit having a methacrylate as a main component is carried out, The block copolymer (B) is produced by a step of polymerizing a monomer constituting the polymer (b2) having a structural unit mainly composed of an acrylate, and is contained as the elastomer component [2].