JP2009052021A - Thermoplastic resin composition, and resin molded article and polarizer protecting film using it, as well as manufacturing method of resin molded article - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin composition, containing a thermoplastic acrylic resin and an ultraviolet absorber (UVA), which has the excellent heat resistance due to the glass transition temperature, and which is suppressed in the occurrence of foaming and bleeding out even at the time of molding at a high temperature, and also which is reduced in the occurrence of the problem resulting from the transpiration of UVA. <P>SOLUTION: The thermoplastic resin composition contains a thermoplastic acrylic resin and an ultraviolet absorber with a molecular weight of 700 or more, and has a glass transition temperature of 110°C or higher. The above ultraviolet absorber has preferably a hydroxyphenyl triazine skeleton. The above acrylic resin has preferably in the main chain the cyclic structure which is, for example, at least one kind selected from a lactone ring structure, a glutaric anhydride structure, a glutarimide structure, an N-substituted maleimide structure and a maleic anhydride structure. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a thermoplastic resin composition suitable as a heat-resistant transparent material, a resin molded product comprising the composition, and a polarizer protective film as a specific example of the resin molded product. Moreover, this invention relates to the polarizing plate provided with the said protective film, an image display apparatus provided with the said polarizing plate, and also relates to the manufacturing method of a resin molded product.

  Thermoplastic acrylic resin represented by polymethyl methacrylate (PMMA) (hereinafter also simply referred to as “acrylic resin”) has excellent optical properties such as high light transmittance, mechanical strength, and moldability. In addition, because of its excellent balance of surface hardness, it is widely used as a transparent material in various industrial products such as automobiles and home appliances. In recent years, the use of optical members such as optical members used in image display devices has increased.

  Acrylic resin may turn yellow when exposed to light containing ultraviolet rays, resulting in a decrease in transparency. As a method for preventing this, a method of adding an ultraviolet absorber (UVA) is known. However, in general UVA, foaming may occur or UVA may bleed out when an acrylic resin composition to which UVA is added is molded. In addition, UVA may evaporate due to heat applied at the time of molding, resulting in a problem that the ultraviolet absorption ability of the obtained resin molded product is lowered or the molding apparatus is contaminated by the evaporated UVA.

  By the way, as an acrylic resin having both transparency and heat resistance, a resin having a ring structure in the main chain is known. A resin having a ring structure in the main chain has a higher glass transition temperature (Tg) than a resin having no ring structure in the main chain. For example, it is easy to dispose a resin near a heat generating part such as a light source in an image display device. It has various practical advantages such as. JP 2007-31537 A (Patent Document 1) discloses an acrylic resin having an N-substituted maleimide structure in the main chain as a ring structure, and JP 2006-328334 A (Patent Document 2). An acrylic resin having a glutarimide structure as a ring structure in the main chain is disclosed. Japanese Unexamined Patent Publication No. 2000-230016 (Patent Document 3) and Japanese Unexamined Patent Publication No. 2006-96960 (Patent Document 4) disclose acrylic resins having a lactone ring structure in the main chain as a ring structure. The lactone ring structure can be formed, for example, by subjecting a polymer having a hydroxyl group and an ester group in the molecular chain to a lactone cyclization condensation reaction.

  As the Tg of the resin or resin composition increases, a higher molding temperature is required. For this reason, when UVA is added to an acrylic resin having a ring structure in the main chain, foaming or UVA bleed-out tends to occur in the obtained resin molded product. In addition, UVA transpiration during molding is likely to decrease, resulting in a decrease in ultraviolet absorption capacity and contamination of the molding apparatus.

In consideration of these problems, triazine compounds, benzotriazole compounds, and benzophenone compounds, which are considered to have a high ultraviolet absorption effect when added in a small amount, have been used in combination with acrylic resins as UVA. . The above compounds are also disclosed in JP-A-2006-328334 described above.
JP 2007-31537 A JP 2006-328334 A JP 2000-230016 A JP 2006-96960 A

  However, these compounds have a problem in compatibility with an acrylic resin having a ring structure in the main chain. Suppressing the occurrence of foaming and bleeding out during molding at high temperatures is not necessarily sufficient. In addition, when an optical member is formed from a resin composition containing an acrylic resin and UVA, the resin composition may be filtered with a polymer filter for the purpose of reducing defects in appearance of the obtained member. However, in this case, it is necessary to further increase the molding temperature of the resin composition. When the molding temperature becomes high, foaming and bleed-out are likely to occur, and problems associated with UVA transpiration (decrease in ultraviolet absorption ability in the obtained resin molded product, contamination of the molding apparatus due to transpiration UVA) are likely to occur. .

  The present invention is a resin composition containing an acrylic resin and UVA, and has excellent heat resistance based on the high glass transition temperature, and the occurrence of foaming, bleed-out, etc. even during molding at high temperatures. An object of the present invention is to provide a resin composition that can suppress the occurrence of problems due to UVA transpiration.

  The resin composition of the present invention includes a thermoplastic acrylic resin (resin (A)) and an ultraviolet absorber (UVA (B)) having a molecular weight of 700 or more, and has a glass transition temperature (Tg) of 110 ° C. or more. .

  The resin molded product of the present invention comprises the resin composition of the present invention. The resin molded product of the present invention is, for example, a film or a sheet.

  The polarizer protective film of this invention is 1 type of the resin molded product of this invention, and consists of the resin composition of the said invention.

  The polarizing plate of the present invention includes a polarizer and the polarizer protective film of the present invention.

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

  In the method for producing a resin molded product of the present invention, the resin composition of the present invention is extruded to form a molded product.

  The resin composition of the present invention exhibits excellent heat resistance based on a high Tg of 110 ° C. or higher, suppresses the occurrence of foaming and bleed-out even during molding at high temperature, and causes less problems due to UVA transpiration. .

  The resin molded product of the present invention composed of such a resin composition has excellent heat resistance based on the height of Tg, high ultraviolet absorbing ability based on UVA (B), and high transparency based on resin (A), machine Strength and moldability. Further, the resin molded product of the present invention has few defects in appearance or optical defects due to foaming or bleed out, and this effect is particularly effective when the resin molded product of the present invention is a film or sheet. In the case of an optical member such as

  In the following description, “%” means “% by weight” and “parts” means “parts by weight” unless otherwise specified.

[Resin composition]
The resin composition of the present invention will be described in detail.

[Resin (A)]
The resin (A) is not particularly limited as long as it is a thermoplastic acrylic resin. However, the resin (A) needs to be an acrylic resin having a Tg of 110 ° C. or more as the resin composition.

  The acrylic resin is a resin having a (meth) acrylic acid ester unit and / or a (meth) acrylic acid unit as a structural unit, and is derived from a (meth) acrylic acid ester or a derivative of (meth) acrylic acid. You may have a unit. The total of the proportion of the structural units derived from the (meth) acrylic acid ester unit, the (meth) acrylic acid unit and the derivative in all the structural units possessed by the acrylic resin is usually 50% or more, preferably 60% or more, More preferably, it is 70% or more.

  The (meth) acrylic acid ester unit is, for example, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, n-butyl (meth) acrylate, t-butyl (meth) acrylate. , N-hexyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, chloromethyl (meth) acrylate, 2-chloroethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate , (Meth) acrylic acid 3-hydroxypropyl, (meth) acrylic acid 2,3,4,5,6-pentahydroxyhexyl, (meth) acrylic acid 2,3,4,5-tetrahydroxypentyl, 2- ( A structural unit derived from monomers such as hydroxymethyl) methyl acrylate and 2- (hydroxyethyl) methyl acrylate That. Resin (A) may have two or more of these structural units as a (meth) acrylic acid ester unit. The resin (A) preferably has a methyl (meth) acrylate unit. In this case, a resin composition containing the resin (A) and the resin (A) and a resin molded product obtained by molding the composition Thermal stability is improved.

  The Tg of the resin (A) is usually 110 ° C. or higher because the Tg of the resin composition containing UVA (B) is 110 ° C. or higher. Since Tg as a resin composition can be improved, 115 degreeC or more is preferable, as for Tg of resin (A), 120 degreeC or more is more preferable, and 130 degreeC or more is further more preferable. Note that Tg of polymethyl methacrylate (PMMA) which is a typical acrylic resin is 105 ° C.

  The resin (A) may have a ring structure in the main chain. In this case, Tg of resin (A) and a resin composition becomes high, and the heat resistance of the resin molded product obtained from the said composition improves. Thus, a resin molded product obtained from a resin composition containing a resin (A) having a ring structure in the main chain, such as a resin film, can be easily arranged in the vicinity of a heat generating part such as a light source in an image display device, etc. Suitable for use as an optical member.

  By the way, when Tg of a resin composition becomes high because resin (A) has a ring structure, it is necessary to raise the molding temperature of the composition (an acrylic resin composition is usually formed into a molded product by extrusion molding). However, in this case, a molding temperature equal to or higher than Tg of the composition is required). When the molding temperature is high, foaming and UVA bleed out are likely to occur during molding, and UVA transpiration tends to be strong. However, in the resin composition of the present invention, even in such a case, the occurrence of foaming and bleeding out is small, and the occurrence of problems due to UVA evaporation can be suppressed.

  Although the kind of ring structure is not specifically limited, For example, it is at least 1 sort (s) chosen from lactone ring structure, glutaric anhydride structure, glutarimide structure, N-substituted maleimide structure, and maleic anhydride structure.

  Since the Tg of the resin (A) and the resin composition is further improved, the ring structure is preferably at least one selected from a glutarimide structure, a glutaric anhydride structure, and a lactone ring structure. Further, since the structure does not contain a nitrogen atom, coloring (yellowing) is unlikely to occur, and the optical characteristics when the resin molded product is obtained are excellent, and the ring structure is preferably a lactone ring structure. That is, the resin (A) is preferably an acrylic resin having a lactone ring structure in the main chain.

  The following formula (1) shows a glutarimide structure and a glutaric anhydride structure.

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

When X ¹ is a nitrogen atom, the ring structure represented by the formula (1) is a glutarimide structure. The glutarimide structure can be formed, for example, by imidizing a (meth) acrylic acid ester polymer with an imidizing agent such as methylamine.

When X ¹ is an oxygen atom, the ring structure represented by the formula (1) is a glutaric anhydride structure. The glutaric anhydride structure can be formed, for example, by subjecting a copolymer of (meth) acrylic acid ester and (meth) acrylic acid to dealcoholization cyclocondensation within the molecule.

  The following formula (2) shows an N-substituted maleimide structure and a maleic anhydride structure.

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

When X ² is a nitrogen atom, the ring structure represented by the formula (2) is an N-substituted maleimide structure. The acrylic resin having an N-substituted maleimide structure in the main chain can be formed, for example, by copolymerizing an N-substituted maleimide and a (meth) acrylic ester.

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

  In each method for forming a ring structure exemplified in the description of formulas (1) and (2), all the polymers used for forming each ring structure have (meth) acrylate units as constituent units. The resin obtained by this method is an acrylic resin.

  The lactone ring structure that the resin (A) may have in the main chain is not particularly limited, and may be, for example, a 4- to 8-membered ring. However, since it is excellent in stability as a ring structure, a 5-membered ring or A 6-membered ring is preferable, and a 6-membered ring is more preferable. The 6-membered lactone ring structure is, for example, the structure disclosed in Japanese Patent Application Laid-Open No. 2004-168882, but the precursor (the lactone ring structure is converted into the main chain by cyclization condensation reaction of the precursor). The polymerization yield of the resin (A) is high), the resin (A) having a high lactone ring content can be obtained by the cyclocondensation reaction of the precursor, and the methyl methacrylate unit is a structural unit. A structure represented by the following formula (3) is preferable because the polymer can be used as a precursor.

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

  The organic residue in Formula (3) is, for example, an alkyl group having 1 to 20 carbon atoms such as a methyl group, an ethyl group, or a propyl group; and an alkyl group having 1 to 20 carbon atoms such as an ethenyl group or a propenyl group. An unsaturated aliphatic hydrocarbon group; an aromatic hydrocarbon group having 1 to 20 carbon atoms such as a phenyl group and a naphthyl group; in the alkyl group, the unsaturated aliphatic hydrocarbon group, and the aromatic hydrocarbon group , A group in which one or more of hydrogen atoms are substituted with at least one group selected from a hydroxyl group, a carboxyl group, an ether group and an ester group.

Although the content rate of the said ring structure (except a lactone ring structure) in resin (A) is not specifically limited, For example, it is 5-90%, 10-70% is preferable, 10-60% is more preferable,
10 to 50% is more preferable.

  When the resin (A) has a lactone ring structure in the main chain, the content of the lactone ring structure in the resin is not particularly limited, but is, for example, 5 to 90%, 20 to 90%, 30 to 90%, 35 to 35%. 90%, 40 to 80%, and 45 to 75% are more preferable.

  When the content of the ring structure in the resin (A) is excessively small, the heat resistance of the resin composition and a resin molded product obtained by molding the composition is lowered, or the solvent resistance and surface hardness are insufficient. May be. On the other hand, when the said content rate becomes large too much, the moldability and handling property of a resin composition will fall.

  The resin (A) having a ring structure in the main chain can be produced by a known method. The resin (A) whose ring structure is a lactone ring structure is, for example, a method described in JP 2006-96960 A (WO 2006/025445), JP 2006-171464 A, or JP 2007-63541 A. Can be manufactured. The resin (A) whose ring structure is an N-substituted maleimide structure, a glutaric anhydride structure or a glutarimide structure is, for example, a method described in JP2007-31537A, WO2007 / 26659, or WO2005 / 108438. Can be manufactured. The resin (A) whose ring structure is a maleic anhydride structure can be produced, for example, by the method described in JP-A-57-153008.

  The resin (A) may have a structural unit other than the (meth) acrylic acid ester unit and the (meth) acrylic acid unit. Examples of such a structural unit include styrene, vinyltoluene, and α-methylstyrene. , Acrylonitrile, methyl vinyl ketone, ethylene, propylene, vinyl acetate, methallyl alcohol, allyl alcohol, 2-hydroxymethyl-1-butene, α-hydroxymethylstyrene, α-hydroxyethylstyrene, 2- (hydroxyethyl) acrylic acid It is a structural unit derived from monomers such as 2- (hydroxyalkyl) acrylic acid ester such as methyl and 2- (hydroxyalkyl) acrylic acid such as 2- (hydroxyethyl) acrylic acid. The resin (A) may have two or more of these structural units.

  Resin (A) may have a structural unit having an effect of giving negative intrinsic birefringence to the resin. In this case, the degree of freedom in controlling the birefringence of the resin composition and the resin molded product obtained by molding the composition is improved, and the resin molded product (for example, resin film) formed from the resin composition of the present invention. Use as an optical member is expanded.

  Intrinsic birefringence refers to the orientation axis from the refractive index n1 of light in a direction parallel to the direction (orientation axis) in which molecular chains are oriented in a layer (for example, a sheet or film) in which resin molecular chains are uniaxially oriented. A value obtained by subtracting the refractive index n2 of the light in the direction perpendicular to (i.e., "n1-n2"). The sign of the intrinsic birefringence of the resin (A) itself is determined by the balance between the action of the structural unit with respect to the intrinsic birefringence and the action of the other structural unit of the resin (A).

  An example of a structural unit having an effect of giving negative intrinsic birefringence to the resin (A) is a styrene unit.

  The resin (A) may have a structural unit (UVA unit) having ultraviolet absorbing ability. In this case, the ultraviolet absorbing ability of the resin composition and the resin molded product obtained by molding the composition is further improved. Depending on the structure of the UVA unit, the compatibility between the resin (A) and the UVA (B) is improved.

The monomer (C) that is the source of the UVA unit is not particularly limited, and is, for example, a benzotriazole derivative, a triazine derivative, or a benzophenone derivative into which a polymerizable group is introduced. The polymerizable group to be introduced can be appropriately selected according to the structural unit of the resin (A).

  Specific examples of the monomer (C) include 2- (2′-hydroxy-5′-methacryloyloxy) ethylphenyl-2H-benzotriazole (manufactured by Otsuka Chemical Co., Ltd., trade name RUVA-93), 2- (2′- Hydroxy-5'-methacryloyloxy) phenyl-2H-benzotriazole, 2- (2'-hydroxy-3'-t-butyl-5'-methacryloyloxy) phenyl-2H-benzotriazole.

  Specific examples of the monomer (C) other than the above are triazine derivatives represented by the following formulas (4), (5) and (6) or benzotriazole derivatives represented by the following formula (7). .

  The monomer (C) is preferably 2- (2'-hydroxy-5'-methacryloyloxy) ethylphenyl-2H-benzotriazole because of its high ultraviolet absorption ability. According to the UVA unit having a high ultraviolet absorbing ability, the desired ultraviolet absorbing effect can be obtained even when the content of the UVA unit in the resin (A) is low. That is, even when the resin (A) contains a UVA unit, the content of constituent units other than the UVA unit can be relatively increased, and characteristics (for example, thermoplasticity and heat resistance) suitable for various uses such as an optical member can be obtained. It becomes easy to obtain the resin composition which has. Further, since the coloration of the resin composition tends to occur when the content of the UVA unit is increased, the UVA unit having a high ultraviolet absorption ability can suppress the coloring of the resin molded product finally obtained, The molded article is suitable for use as an optical member.

  When resin (A) contains a UVA unit, the content of the unit in resin (A) is preferably 20% or less, and more preferably 15% or less. When the content of the UVA unit in the resin (A) exceeds 20%, the heat resistance as the resin composition is lowered.

  The weight average molecular weight of the resin (A) is, for example, in the range of 1,000 to 300,000, preferably in the range of 5,000 to 250,000, more preferably in the range of 10,000 to 200,000, and still more preferably in the range of 50,000 to 200,000.

[UVA (B)]
The molecular weight of UVA (B) is 700 or more. The molecular weight is preferably 800 or more, and more preferably 900 or more. On the other hand, when the molecular weight exceeds 10,000, the compatibility with the resin (A) is lowered, so that optical properties such as hue and turbidity of the finally obtained resin molded product are lowered. The upper limit of the molecular weight of UVA (B) is preferably 8000 or less, and more preferably 5000 or less.

  It is preferable that UVA (B) does not contain a repeating unit derived from a monomer (that is, it is not a polymer). When a repeating unit derived from a monomer is included, the resin composition tends to be colored during molding by a polymerization initiator or a chain transfer agent remaining in UVA.

  UVA (B) may be a mixture of two or more compounds, and in this case, the molecular weight of the main component compound may be 700 or more. In addition, the main component in this specification means a component with most content (content rate), and the content rate is typically 50% or more.

  UVA (B) may be solid or liquid at room temperature, but solid UVA is preferably liquid at room temperature because sublimation during molding tends to be a problem.

In UVA (B), the molar extinction coefficient of the maximum absorption wavelength for light in the wavelength range of 300 nm to 380 nm is preferably 10,000 (L · mol ⁻¹ · cm ⁻¹ ) or more in the chloroform solution.

  The structure of UVA (B) is not particularly limited as long as the molecular weight is 700 or more, but UVA (B) preferably has a hydroxyphenyltriazine skeleton. The hydroxyphenyl triazine skeleton is a skeleton ((2-hydroxyphenyl) -1,3,5-triazine skeleton) composed of triazine and three hydroxyphenyl groups bonded to the triazine. The hydrogen atom of the hydroxyl group in the hydroxyphenyl group forms a hydrogen bond with the nitrogen atom of triazine, and the formed hydrogen bond increases the action of the phenyl triazine as a chromophore. Since three hydrogen bonds are formed in UVA (B), the action as a chromophore possessed by phenyltriazine can be further increased, and a high ultraviolet absorbing ability can be obtained with a small addition amount. In addition, when UVA (B) consists of a mixture of 2 or more types of compounds, it is preferable that the compound which is at least a main component has a hydroxyphenyl triazine skeleton.

The hydroxyphenyl group in the hydroxyphenyltriazine skeleton may be bonded to a substituent such as an alkyl group or an alkyl ester group, but the substituent does not have a structure that can serve as a crosslinking point with the resin (A). It is preferable. The structure that can be a crosslinking point is, for example, a functional group such as a hydroxyl group, a thiol group, or an amine group, or a double bond. The alkyl ester group is preferably a group represented by the formula “—CH (—R ¹⁰ ) C (═O) OR ¹¹ ”. In the above formula, R ¹⁰ is a hydrogen atom or a methyl group, and R ¹¹ is a linear or branched alkyl group.

  Although the resin composition of the present invention contains a thermoplastic acrylic resin (A) and UVA (B), the Tg as the composition is 110 ° C. or higher, and the temperature required for molding (for example, extrusion molding) is high. Gel may form during molding. Gels tend to form as the molding temperature increases. That is, in the case where the resin (A) has a ring structure in the main chain, the higher the Tg of the composition, the higher the required molding temperature and the easier the gel is formed.

If there is a structure that can be a crosslinking point with the resin (A) in the substituent of the hydroxyphenyl group in the hydroxyphenyltriazine skeleton, the possibility of generating a gel during molding of the resin composition increases. In other words, by using UVA (B) that does not have a structure that can be a crosslinking point with the resin (A) in the substituent, it is possible to suppress the occurrence of gel during molding of the resin composition and A resin film (for example, a polarizer protective film) with few defects is obtained. Moreover, since the molding temperature of the composition can be further increased by suppressing the generation of gel, (1) the melt viscosity of the composition during molding is lowered and the productivity of the resin molded product is improved. (2) When filtering with a polymer filter at the time of molding for the purpose of removing foreign substances such as gel, effects such as a longer filter replacement cycle can be obtained by suppressing the generation of gel.

  The hydroxyphenyl group has a hydroxyl group as a substituent, but the hydroxyl group directly bonded to the benzene ring does not form a crosslinked structure with the resin (A), and therefore is treated as a structure that can be a crosslinking point with the resin (A). Absent.

  By the way, there is triacetyl cellulose (TAC) as one of the materials used as an optical member. However, since TAC has a decomposition temperature as low as about 250 ° C., extrusion molding cannot be used. It is formed into a film by (cast method). That is, since the TAC itself is not exposed to a high temperature during the formation of the TAC film, whether or not there is a structure in the UVA that can be a crosslinking point with the TAC depends on the occurrence frequency and productivity of optical defects in the TAC film. Does not affect.

  UVA (B) has, for example, a structure represented by the following formula (8).

  Examples of the commercially available ultraviolet absorber containing UVA (B) represented by the above formula (8) as a main component include CGL777MPA (manufactured by Ciba Specialty Chemicals) or CGL777MPAD (manufactured by Ciba Specialty Chemicals).

[Resin composition]
Although content of UVA (B) in the resin composition of this invention is not specifically limited, For example, it is 0.1-5 parts with respect to 100 parts of thermoplastic resins including resin (A). If the content of UVA (B) is excessively small, sufficient ultraviolet absorbing ability cannot be obtained. On the other hand, when the content of UVA (B) becomes excessively large, the demerit that foaming or bleed out occurs at the time of molding becomes larger than the merit of improving the ultraviolet absorbing ability.

  The UVA (B) content in the resin composition of the present invention is preferably 0.5 to 5 parts UVA (B) with respect to 100 parts of the thermoplastic resin, 0.7 to 3 parts, 1 to 3 parts, It is more preferable that it is ˜2 parts.

The main component of the thermoplastic resin contained in the resin composition of the present invention is the resin (A). Specifically, the ratio of the resin (A) in the entire thermoplastic resin contained in the resin composition of the present invention is usually 60% or more, preferably 70% or more, more preferably 85% or more. In other words, the resin composition of the present invention has a thermoplastic resin other than the resin (A) in a proportion of less than 40% (preferably less than 30%) as a percentage of the entire thermoplastic resin contained in the composition. Range, more preferably less than 15%).

  Such thermoplastic resins include, for example, olefin polymers such as polyethylene, polypropylene, ethylene-propylene copolymer, poly (4-methyl-1-pentene); halogen-containing polymers such as vinyl chloride and chlorinated vinyl resins; polystyrene Styrene polymer such as styrene-methyl methacrylate copolymer, styrene-acrylonitrile copolymer, acrylonitrile-butadiene-styrene block copolymer; polyester such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate; nylon 6, nylon 66 , Polyamides such as nylon 610; polyacetal: polycarbonate; polyphenylene oxide; polyphenylene sulfide: polyetheretherketone; polysulfone; Rusaruhon; polyoxyethylene Penji alkylene; polyamideimide; polybutadiene rubber or ABS resin containing an acrylic rubber, rubber-like polymer such as ASA resin; and the like. The rubbery polymer preferably has on its surface a graft portion having a composition compatible with the resin (A). When the rubbery polymer is in the form of particles, the average particle size is determined according to the present invention. From the viewpoint of improving transparency when the resin composition is a resin film, 300 nm or less is preferable, and 150 nm or less is more preferable.

  Among the above-exemplified thermoplastic resins, compatibility with the resin (A), in particular, compatibility with the resin (A) having a lactone ring structure in the main chain, is derived from the vinyl cyanide monomer. A copolymer containing a structural unit and a structural unit derived from an aromatic vinyl monomer is preferred. The copolymer is, for example, a styrene-acrylonitrile copolymer or a vinyl chloride resin.

  The resin composition of the present invention has a high glass transition temperature (Tg) of 110 ° C. or higher. Depending on the composition of the resin (A) (for example, whether the resin (A) has a ring structure in the main chain, or the content of the ring structure when the resin (A) has a ring structure in the main chain). The Tg of the resin composition of the present invention is 115 ° C or higher, 120 ° C or higher, and further 130 ° C or higher. In addition, Tg in this specification shall be the value calculated | required by the starting point method using the differential scanning calorimeter (DSC) based on prescription | regulation of JISK7121.

  The resin composition of the present invention has an ultraviolet absorbing ability based on UVA (B). For example, when the film has a thickness of 100 μm, the transmittance of light having a wavelength of 380 nm is less than 30%, and in some cases, 20%. Less than, or even less than 10% and less than 1%. What is necessary is just to measure this transmittance | permeability based on prescription | regulation of JISK7361: 1997.

  The resin composition of the present invention has a high visible light transmittance based on the compatibility between the resin (A) and the UVA (B). For example, when the film has a thickness of 100 μm, it transmits light having a wavelength of 500 nm. The rate can be 80% or more, in some cases 85% or more, and even 90% or more. This transmittance can be measured in the same manner as the transmittance of light having a wavelength of 380 nm.

  With the resin composition of the present invention, sublimation of UVA (B) during and after molding can be suppressed. For example, although details will be described later in Examples, when a film having a predetermined size is obtained, a volatile component obtained by heating the film at 150 ° C. for 10 hours is dissolved in a volume of 1 mL of a solvent (for example, chloroform) to obtain a film. The absorbance of light having a wavelength of 350 nm as measured with an absorptiometer when the obtained solution is accommodated in a quartz cell having an optical path length of 1 cm can be less than 0.05. Note that when the amount of sublimation of UVA increases, the amount of UVA in the volatile component increases, and thus the absorbance of the solution in which the component is dissolved increases.

  In the resin composition of the present invention, the hue of the composition and a resin molded product obtained by molding the composition can be improved by the combination of the resin (A) and the UVA (B).

  The resin composition of the present invention is less colored at the time of molding. For example, the b value in the Lab color system (hunter color system) when it is a film having a thickness of 100 μm is 3.0 or less, and in some cases, 2.0. It can be as follows. Conventional acrylic resin compositions having ultraviolet absorbing ability are often colored (yellowing) during molding, but such coloration can be suppressed in the resin composition of the present invention.

  The resin composition of the present invention is excellent in thermal stability, and the 5% weight loss temperature evaluated by thermogravimetric analysis (TG) is 280 ° C or higher, in some cases 290 ° C or higher, further 300 ° C or higher. it can.

  In the resin composition of the present invention, the total content of components having a boiling point of Tg or less of the composition is preferably 5000 ppm or less, and more preferably 3000 ppm or less. When the total content of the above components exceeds 5000 ppm, coloring may occur during molding, or molding defects such as silver streak may occur.

  The resin composition of the present invention may contain a polymer having negative intrinsic birefringence. In this case, the freedom degree of control of the birefringence (for example, phase difference) in the resin composition and the resin molded product obtained by molding the composition is improved.

  The polymer having negative intrinsic birefringence is, for example, a copolymer of a vinyl cyanide monomer and an aromatic vinyl monomer. The copolymer is, for example, a styrene-acrylonitrile copolymer, and the styrene-acrylonitrile copolymer is excellent in compatibility with the resin (A) in a wide range of copolymer compositions.

  The styrene-acrylonitrile copolymer can be produced by various polymerization methods such as emulsion polymerization, suspension polymerization, solution polymerization, and bulk polymerization. When a resin molded article formed from the resin composition of the present invention is used as an optical member, it is preferable to use a styrene-acrylonitrile copolymer produced by solution polymerization or bulk polymerization because transparency and optical properties are improved. .

  The resin composition of the present invention may contain an antioxidant. Although antioxidant is not specifically limited, For example, well-known antioxidants, such as a hindered phenol type, a phosphorus type, or a sulfur type, can be used by 1 type or in combination of 2 or more types. In particular, 2,4-di-t-amyl-6- [1- (3,5-di-t-amyl-2-hydroxyphenyl) ethyl] phenyl acrylate (e.g., Sumitizer GS manufactured by Sumitomo Chemical), and 2-t-butyl-6- (3-t-butyl-2-hydroxy-5-methylbenzyl) -4-methylphenyl acrylate (for example, Sumitizer GM manufactured by Sumitomo Chemical Co., Ltd.) is a resin composition during high temperature molding. It is preferable because it has a high effect of suppressing the deterioration.

The antioxidant may be a phenolic antioxidant. Examples of the phenolic antioxidant include n-octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) -propionate and n-octadecyl-3- (3,5-di-t-butyl. -4-hydroxyphenyl) -acetate, n-octadecyl-3,5-di-t-butyl-4-hydroxybenzoate, n-hexyl-3,5-di-t-butyl-4-hydroxyphenylbenzoate, n- Dodecyl-3,5-di-t-butyl-4-hydroxyphenylbenzoate, neo-dodecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, dodecyl-β (3,5- Di-t-butyl-4-hydroxyphenyl) propionate, ethyl-α- (4-hydroxy-3,5-di-t-butylphenyl) isobutyrate Octadecyl-α- (4-hydroxy-3,5-di-t-butylphenyl) isobutyrate, octadecyl-α- (4-hydroxy-3,5-di-t-butyl-4-hydroxyphenyl) propionate, 2 -(N-octylthio) ethyl-3,5-di-t-butyl-4-hydroxy-benzoate, 2- (n-octylthio) ethyl-3,5-di-t-butyl-4-hydroxy-phenylacetate, 2- (n-octadecylthio) ethyl-3,5-di-t-butyl-4-hydroxyphenyl acetate, 2- (n-octadecylthio) ethyl-3,5-di-t-butyl-4-hydroxybenzoate 2- (2-hydroxyethylthio) ethyl-3,5-di-t-butyl-4-hydroxybenzoate, diethyl glycol-bis- (3 , 5-Di-tert-butyl-4-hydroxy-phenyl) propionate, 2- (n-octadecylthio) ethyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, stearamide-N , N-bis- [ethylene-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], n-butylimino-N, N-bis- [ethylene-3- (3,5-di -T-butyl-4-hydroxyphenyl) propionate], 2- (2-stearoyloxyethylthio) ethyl-3,5-di-t-butyl-4-hydroxybenzoate, 2- (2-stearoyloxyethylthio) Ethyl-7- (3-methyl-5-tert-butyl-4-hydroxyphenyl) heptanoate, 1,2-propylene glycol-bis- [3- ( , 5-di-t-butyl-4-hydroxyphenyl) propionate], ethylene glycol-bis- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], neopentyl glycol-bis- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], ethylene glycol-bis- (3,5-di-t-butyl-4-hydroxyphenyl acetate), glycerin-1-n -Octadecanoate-2,3-bis- (3,5-di-t-butyl-4-hydroxyphenylacetate), pentaerythritol-tetrakis- [3- (3 ', 5'-di-t-butyl) -4'-hydroxyphenyl) propionate], 1,1,1-trimethylolethane-tris- [3- (3,5-di-t-butyl-4- Droxyphenyl) propionate], sorbitol hexa- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 2-hydroxyethyl-7- (3-methyl-5-t-butyl- 4-hydroxyphenyl) propionate, 2-stearoyloxyethyl-7- (3-methyl-5-tert-butyl-4-hydroxyphenyl) heptanoate, 1,6-n-hexanediol-bis [(3 ', 5' -Di-t-butyl-4-hydroxyphenyl) propionate], pentaerythritol-tetrakis (3,5-di-t-butyl-4-hydroxyhydrocinnamate), 3,9-bis [1,1-dimethyl- 2- [β- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy] ethyl] 2,4,8 10-tetraoxaspiro [5,5] - undecanoic.

  The phenolic antioxidant is preferably used in combination with a thioether antioxidant or a phosphoric acid antioxidant. The amount of the antioxidant added in combination is, for example, 0.01 parts or more of each of the phenolic antioxidant and the thioether antioxidant with respect to 100 parts of the resin (A), or 100 parts of the resin (A). On the other hand, each of the phenolic antioxidant and the phosphoric acid antioxidant is 0.025 part or more.

  Examples of the thioether-based antioxidant include pentaerythrityl tetrakis (3-laurylthiopropionate), dilauryl-3,3′-thiodipropionate, dimyristyl-3,3′-thiodipropionate, distearyl- 3,3′-thiodipropionate.

Examples of the phosphoric acid antioxidant include tris (2,4-di-t-butylphenyl) phosphite, 2-[[2,4,8,10-tetrakis (1,1-dimethylethyl) dibenzo [d. , F] [1,3,2] dioxaphosphin-6-yl] oxy] -N, N-bis [2-[[2,4,8,10-tetrakis (1,1 dimethylethyl) dibenzo [D, f] [1,3,2] dioxaphosphin-6-yl] oxy] -ethyl] ethanamine, diphenyltridecyl phosphite, triphenyl phosphite, 2,2-methylenebis (4,6- Di-t-butylphenyl) octyl phosphite, bis (2,6-di-t-butyl-4-methylphenyl) pentaerythritol diphosphite, distearyl pentaerythritol diphosphite Cyclic neopentanetetraylbis is (2,6-di -t- butyl-4-methylphenyl) phosphite.

  The addition amount of the antioxidant in the resin composition of the present invention is, for example, 0 to 10%, preferably 0 to 5%, more preferably 0.01 to 2%, and further preferably 0.05 to 1%. When the amount of the antioxidant added is excessively large, the antioxidant bleed out or silver streaks may occur during molding.

  The resin composition of the present invention may contain other additives. Other additives include, for example, a stabilizer such as a light stabilizer, a weather stabilizer, and a heat stabilizer; a reinforcing material such as a glass fiber and a carbon fiber; a near infrared absorber; a tris (dibromopropyl) phosphate, a triallyl phosphate, Flame retardants such as antimony oxide; antistatic agents typified by anionic, cationic, and nonionic surfactants; colorants such as inorganic pigments, organic pigments, dyes; organic fillers, inorganic fillers; resin modifiers; Plasticizers; lubricants; flame retardants. The addition amount of the other additives in the resin composition of the present invention is, for example, 0 to 5%, preferably 0 to 2%, and more preferably 0 to 0.5%.

  The resin composition of the present invention can be formed into an arbitrary shape such as a film or sheet by a known molding technique such as injection molding, blow molding, extrusion molding or cast molding. The molding temperature may be appropriately set according to the Tg and characteristics of the resin composition, and is not particularly limited, but is, for example, 150 to 350 ° C, and preferably 200 to 300 ° C.

  The resin molded product obtained by molding the resin composition of the present invention has few defects such as foaming and bleed out, and has high ultraviolet absorption ability, heat resistance and transparency.

[Method for Producing Resin Composition]
The resin composition of the present invention can be produced by mixing a thermoplastic resin mainly composed of the resin (A) and UVA (B) by a known method. The produced resin composition may be pelletized with a pelletizer or the like, if necessary.

  The timing which mixes a thermoplastic resin and UVA (B) is not specifically limited unless the above-mentioned various characteristics as a resin composition are inhibited. UVA (B) may be added during polymerization of a thermoplastic resin (for example, resin (A)), or after polymerization of the thermoplastic resin, the obtained thermoplastic resin and UVA (B) are mixed (for example, Melt kneading). The specific method for melt-kneading the thermoplastic resin and UVA (B) is not particularly limited. For example, the thermoplastic resin, UVA (B) and other components to be added may be simultaneously heated and melted and kneaded. Alternatively, after the thermoplastic resin and other components to be added are heated and melted, UVA (B) may be further added thereto and kneaded. Further, after the thermoplastic resin is heated and melted, UVA (B) and other components to be added may be further added and kneaded.

[Resin molding]
The resin molded product of the present invention comprises the resin composition of the present invention. The resin molded product of the present invention has various characteristics based on the characteristics of the above-described resin composition of the present invention. For example, the resin molded product of the present invention has high ultraviolet absorption ability, heat resistance and transparency. For example, the resin molded product of the present invention has few defects such as foaming and bleeding out.

  Due to these characteristics, the resin molded product of the present invention can be suitably used as an optical member. Further, due to the high heat resistance, it can be placed close to a heat generating part such as a light source.

  The shape of the resin molded product of the present invention is not particularly limited, and is, for example, a film or a sheet.

  The thickness of the resin molded product of the present invention that is a film is, for example, 1 μm or more and less than 350 μm, and preferably 10 μm or more and less than 350 μm. When the thickness is less than 1 μm, the strength as a resin film may be insufficient, and breakage or the like is likely to occur during post-processing such as stretching.

  The thickness of the resin molded product of the present invention which is a sheet is, for example, 350 μm or more and 10 mm or less, preferably 350 μm or more and 5 mm or less. When the thickness exceeds 10 mm, it becomes difficult to make the sheet thickness uniform, and it becomes difficult to use the resin sheet as an optical member.

  The resin sheet and the resin film can be formed, for example, by extruding the resin composition of the present invention.

  The resin molded product of the present invention has a high Tg, for example, a value of 110 ° C. or higher. Depending on the composition of the resin composition constituting the resin sheet and the resin film, Tg is 115 ° C. or higher, 120 ° C. or higher, and further 130 ° C. or higher.

  The resin molded product of the present invention has a high ultraviolet absorbing ability. For example, when the film has a thickness of 100 μm, the transmittance of light having a wavelength of 380 nm can be less than 30%, sometimes less than 20%, further less than 10%, and less than 1%.

  The resin molded product of the present invention has a high visible light transmittance. For example, when a film having a thickness of 100 μm is used, the transmittance of light having a wavelength of 500 nm can be 80% or more, in some cases 85% or more, 90% or more, and further 92% or more. The transmittance of the film (sheet) with respect to light having a wavelength of 380 nm and light having a wavelength of 500 nm may be measured according to the method described above.

  The resin molded product of the present invention preferably has a tensile strength measured according to ASTM-D-882-61T of 10 MPa or more and less than 100 MPa, and more preferably 30 MPa or more and less than 100 MPa. When the said tensile strength is less than 10 Mpa, the mechanical strength as a resin sheet (film) may become inadequate. On the other hand, when the tensile strength exceeds 100 MPa, the workability decreases.

  The resin molded article of the present invention preferably has an elongation percentage measured according to ASTM-D-882-61T of 1% or more. Although the upper limit of the said elongation rate is not specifically limited, Usually, it is 100% or less. When the said elongation rate is less than 1%, the toughness as a resin sheet (film) may become inadequate.

  The resin molded product of the present invention preferably has a tensile elastic modulus measured according to ASTM-D-882-61T of 0.5 GPa or more, more preferably 1 GPa or more, and 2 GPa or more. More preferably. Although the upper limit of the said tensile elasticity modulus is not specifically limited, Usually, it is 20 GPa or less. When the said tensile elasticity modulus is less than 0.5 GPa, the mechanical strength as a resin sheet (film) may become inadequate.

  Various functional coating layers may be formed on the surface of the resin molded product of the present invention which is a sheet or a film, if necessary. Functional coating layers include, for example, antistatic layers, adhesive layers, adhesive layers, easy adhesion layers, antiglare (non-glare) layers, antifouling layers such as photocatalyst layers, antireflection layers, hard coat layers, and UV shielding layers. Layers, heat ray shielding layers, electromagnetic wave shielding layers, gas barrier layers, and the like. Moreover, the member which has the functional coating layer mentioned above may be laminated | stacked on the resin molded product of this invention. Lamination of the member can be performed via an adhesive or an adhesive.

  Although the use of the resin molded product of the present invention which is a sheet or a film is not particularly limited, it can be suitably used as an optical member due to its high transparency, heat resistance and ultraviolet absorbing ability. The optical member is, for example, an optical protective film (sheet), specifically, a protective film for various optical disk (VD, CD, DVD, MD, LD, etc.) substrates, and an image display device such as a liquid crystal display (LCD). It is a polarizer protective film used for the polarizing plate with which is provided. Retardation film, viewing angle compensation film, light diffusion film, reflection film, antireflection film, antiglare film, brightness enhancement film, optical film such as touch panel conductive film, or diffusion plate, light guide, retardation plate The resin molded product of the present invention may be used as an optical sheet such as a prism sheet.

  A polarizer protective film will be described as an example. A pair of polarizing plates is arranged in the LCD so as to sandwich the liquid crystal cell based on the principle of image display. The polarizing plate generally includes a polarizer made of a resin film such as polyvinyl alcohol, and a polarizer protective film for protecting the polarizer. According to the polarizer protective film of the present invention, deterioration of the polarizer due to ultraviolet rays can be suppressed due to its high ultraviolet absorbing ability. Further, the high heat resistance makes it possible to dispose the polarizing plate close to the light source, and the high transparency makes it possible to form an image display device having excellent image display characteristics.

  Conventionally, a triacetyl cellulose (TAC) film has been used as the polarizer protective film. However, the TAC film does not have sufficient moisture and heat resistance, and when the TAC film is used as a polarizer protective film, the characteristics of the polarizing plate may be deteriorated under a high temperature or high humidity environment. Further, the TAC film has a retardation in the thickness direction, and this retardation adversely affects the viewing angle characteristics of an image display device such as an LCD, particularly a large screen image display device. On the other hand, since the polarizer protective film of this invention consists of a resin composition which has an acrylic resin as a main component, it can improve heat-and-moisture resistance and optical characteristics compared with a TAC film.

  The structure of the polarizing plate including the polarizer protective film of the present invention (the polarizing plate of the present invention) is not particularly limited, and may be a structure in which a polarizer protective film is laminated on one surface of the polarizer. The polarizer may be sandwiched between the polarizer protective films. A typical example of the structure of the polarizing plate of the present invention is an adhesive on one or both sides of a polarizer obtained by uniaxially stretching a polyvinyl alcohol film dyed with a dichroic substance such as iodine or a dichroic dye. It is the structure which joined the polarizer protective film of this invention through the layer or the easily bonding layer.

  The polarizer is not particularly limited. For example, a polarizer obtained by dyeing and stretching a polyvinyl alcohol film; a polyene polarizer such as dehydrated polyvinyl alcohol or dehydrochlorinated polyvinyl chloride; a multilayer laminate or a cholesteric liquid crystal It is a known polarizer such as a reflective polarizer used; a polarizer comprising a thin film crystal film; Among these, a polarizer obtained by dyeing and stretching polyvinyl alcohol is preferable. The thickness of the polarizer is not particularly limited, and is generally about 5 to 100 μm.

When the polarizer and the polarizer protective film are bonded, the adhesive used for bonding is not particularly limited. The adhesive is, for example, an adhesive based on a resin such as polyurethane, polyester, or polyacryl, or various pressure-sensitive adhesives such as acrylic, silicon, or rubber. The polarizer and the polarizer protective film may be joined by thermocompression bonding as long as the function of the polarizer is not impaired.

  The method for bonding the polarizer and the polarizer protective film may be in accordance with a known method. For example, the polarizer, the casting method, the Meyer bar coating method, the gravure coating method, the die coating method, the dip coating method, the spraying method, etc. And after apply | coating an adhesive agent to the adhesive surface of a polarizer protective film, both should just be piled up. In addition, the casting method at the time of apply | coating an adhesive agent is a method of flowing down and spreading an adhesive agent on the surface, moving the film which is application object.

  When bonding the polarizer and the polarizer protective film, the surface of the polarizer protective film on which the polarizer is bonded may be subjected to an easy adhesion treatment. In this case, the adhesiveness between the two is improved. The easy adhesion treatment is, for example, plasma treatment, corona treatment, ultraviolet irradiation treatment, flame (flame) treatment, saponification treatment, or anchor layer formation treatment. Two or more treatments may be used in combination. Among these, a corona treatment, an anchor layer formation treatment, and a method using these in combination are preferable.

  The polarizing plate of the present invention may have any member in addition to the polarizer and the polarizer protective film of the present invention. The member is, for example, a TAC film, a polycarbonate film, a cyclic polyolefin film, an acrylic resin film, a polyethylene terephthalate film, or a polynaphthalene terephthalate film. Especially, since it is excellent in the optical characteristic as a polarizing plate, an acrylic resin film is preferable. Further, since the viewing angle characteristics of the image display device are improved, a low retardation film having a value of 10 nm or less or a specific retardation value in a plane and in a thickness direction (a phase difference per 100 μm thickness with respect to light having a wavelength of 589 nm) is specified. A form having a retardation film having a retardation of 1 is also preferred. These arbitrary films may or may not function as a polarizer protective film.

  The polarizing plate of the present invention may have a hard coat layer for the purpose of improving its surface characteristics, for example, scratch resistance. The hard coat layer is made of, for example, a silicone resin, an acrylic resin, an acrylic silicone resin, an ultraviolet curable resin, or a urethane hard coat agent. Examples of the ultraviolet curable resin include ultraviolet curable acrylic urethane, ultraviolet curable epoxy acrylate, ultraviolet curable (poly) ester acrylate, and ultraviolet curable oxetane. The thickness of the hard coat layer is usually 0.1 to 100 μm. Before the hard coat layer is formed, the underlying layer may be subjected to a primer treatment, and the layer may be subjected to a known anti-glare treatment such as an antireflection treatment or a low reflection treatment.

  The polarizing plate of the present invention may have an adhesive layer in at least one outermost layer. In this case, the polarizing plate of the present invention can be bonded to a liquid crystal cell or other optical member. The pressure-sensitive adhesive layer includes a pressure-sensitive adhesive based on, for example, an acrylic resin, silicone polymer, polyester, polyurethane, polyamide, polyether, fluororesin, rubber or the like.

  The pressure-sensitive adhesive layer can be formed by a known method. For example, the pressure-sensitive adhesive is dissolved or dispersed in a solvent containing a solvent such as toluene or ethyl acetate to prepare a pressure-sensitive adhesive solution having a concentration of about 10 to 40%, and the prepared solution is cast or coated to form a pressure-sensitive adhesive layer. And it is sufficient. The pressure-sensitive adhesive layer can also be formed by transferring a layer obtained by casting or coating the prepared solution onto the separator from the separator.

An anchor layer may be provided between the pressure-sensitive adhesive layer and the underlying layer in order to improve the adhesion between them. The anchor layer is made of, for example, polyurethane, polyester, or a polymer having an amino group in the molecule. Of these, an anchor layer made of a polymer having an amino group in the molecule is preferable. Since the amino group in the polymer reacts with a polar group (for example, a carboxyl group) in the pressure-sensitive adhesive or exhibits an ionic interaction with the polar group, good adhesion is ensured.

  The polymer having an amino group in the molecule is, for example, polyethyleneimine, polyallylamine, polyvinylamine, polyvinylpyridine, polyvinylpyrrolidine, and may be a polymer of a monomer containing an amino group such as dimethylaminoethyl acrylate. .

  The polarizing plate of the present invention can be used for image display devices including LCDs. When the polarizing plate of the present invention is used for an LCD, the polarizing plate may be disposed on only one of the viewing side or the backlight side of the liquid crystal cell, or on both sides.

  The image display apparatus in which the polarizing plate of the present invention can be used is not particularly limited, and examples thereof include reflective, transmissive, and transflective LCDs; TN, STN, OCB, HAN, VA, IPS, and the like. An LCD having various driving methods; an electroluminescence (EL) display; a plasma display (PD); a field emission display (FED).

  The configuration of the image display device including the polarizing plate of the present invention (the image display device of the present invention) is not particularly limited as long as members such as a retardation plate, an optical compensation sheet, and a backlight unit are appropriately provided as necessary. Good.

  FIG. 1 shows an example of the structure of the image display unit in the image display apparatus of the present invention. An image display unit 11 illustrated in FIG. 1 is an image display unit of an LCD, and includes a liquid crystal cell 4, a pair of polarizing plates 9 and 10 disposed so as to sandwich the liquid crystal cell 4, and the liquid crystal cell 4 and the polarizing plate 9. 10 and a backlight 8 disposed on one surface of the laminated body. Each polarizing plate 9, 10 includes polarizers 2, 6 and a pair of polarizer protective films 1, 3, 5, 7 arranged so as to sandwich the polarizer. The liquid crystal cell 4 has a known structure, and includes, for example, a liquid crystal layer, a glass substrate, a transparent electrode, an alignment film, and the like. The backlight 8 has a known structure, and includes, for example, a light source, a reflection sheet, a light guide plate, a diffusion plate, a diffusion sheet, a prism sheet, and a brightness enhancement film.

  In the image display unit 11, at least one selected from the four polarizer protective films may be the polarizer protective film of the present invention, and all the polarizer protective films are preferably the polarizer protective films of the present invention. When ultraviolet rays incident on the image display unit 11 from the outside become a problem, the polarizer of the polarizing plate 9 located on the viewing side (external side) among the polarizing plates 9 and 10 disposed on both sides of the liquid crystal cell 4. The protective film is preferably the polarizer protective film of the present invention, and among the polarizer protective films 1 and 3 of the polarizing plate 9, at least the film 1 positioned on the outer side is the polarizer protective film of the present invention. More preferred.

  The image display unit 11 may further include an arbitrary optical member such as a retardation plate or an optical compensation sheet as necessary.

[Production method of resin molded product]
As described above, the method for producing a resin molded product of the present invention is not particularly limited, but an example of a method for producing a resin film as a resin molded product will be shown below. This manufacturing method can also be applied to a method for manufacturing a resin sheet.

As a method for producing a resin film from the resin composition of the present invention, there is an extrusion molding method. As a specific example, after each component constituting the resin composition is pre-blended with a mixer such as an omni mixer, the resulting mixture may be extrusion kneaded from a kneader. The kneader used for the extrusion kneading is not particularly limited, and for example, a known kneader such as a single screw extruder, a twin screw extruder, or a pressure kneader can be used.

  Alternatively, a separately formed resin composition may be melt-extruded. Examples of the melt extrusion method include a T-die method and an inflation method, and the molding temperature at that time is preferably 200 to 350 ° C., more preferably 250 to 300 ° C., further preferably 255 to 300 ° C., particularly Preferably it is 260 to 300 degreeC.

  When the T-die method is used, a resin film wound into a roll can be obtained by attaching a T-die to the tip of the extruder and winding the film extruded from the T-die. At this time, it is also possible to control the temperature and speed of winding and to stretch (uniaxial stretching) in the extrusion direction of the film. Further, the film may be stretched in a direction perpendicular to the extrusion direction, and sequential biaxial stretching or simultaneous biaxial stretching may be performed.

  When an extruder is used for extrusion molding, the type is not particularly limited and may be uniaxial, biaxial, or multiaxial, but its L / D value is (L is the value of the extruder) In order to sufficiently plasticize the resin composition to obtain a good kneaded state, the length of the cylinder, D is the cylinder inner diameter) is preferably 10 or more and 100 or less, more preferably 20 or more and 50 or less, and further preferably 25 or more and 40 or less. . When the L / D value is less than 10, the resin composition cannot be sufficiently plasticized and a good kneaded state may not be obtained. On the other hand, if the L / D value exceeds 100, the resin in the composition may be thermally decomposed due to excessive generation of shear heat to the resin composition.

  In this case, the set temperature of the cylinder is preferably 200 ° C. or higher and 300 ° C. or lower, and more preferably 250 ° C. or higher and 300 ° C. or lower. If setting temperature is less than 200 degreeC, the melt viscosity of a resin composition will become high too much, and the productivity of a resin film will fall. On the other hand, if the set temperature exceeds 300 ° C., the resin in the resin composition may be thermally decomposed.

  When an extruder is used for extrusion molding, the shape is not particularly limited, but the extruder preferably has one or more open vent portions. By using such an extruder, the decomposition gas can be sucked from the open vent portion, and the amount of volatile components remaining in the obtained resin film can be reduced. In order to suck the decomposition gas from the open vent portion, for example, the open vent portion may be in a reduced pressure state, and the degree of pressure reduction is 931 to 1.3 hPa (700 to 1 mmHg) as the pressure of the open vent portion. The range is preferable, and the range of 798 to 13.3 hPa (600 to 10 mmHg) is more preferable. When the pressure in the open vent portion is higher than 931 hPa, volatile components or monomer components generated by decomposition of the resin tend to remain in the resin composition. On the other hand, it is industrially difficult to keep the pressure of the open vent part lower than 1.3 hPa.

  When producing a resin film used as an optical member such as an optical film, a resin composition filtered with a polymer filter may be molded. Since the foreign matter present in the resin composition can be removed by the polymer filter, defects in the appearance of the obtained film can be reduced. In addition, the resin composition will be in a high temperature molten state at the time of filtration with a polymer filter. For this reason, the resin composition deteriorates when passing through the polymer filter, gas components and colored deterioration products formed by the deterioration flow into the composition, and the resulting film is perforated, flow pattern, flow Defects such as streaks may be observed. This defect is particularly easily observed during continuous molding of a resin film. For this reason, when molding the resin composition filtered through the polymer filter, the molding temperature decreases the melt viscosity of the resin composition and shortens the residence time of the resin composition in the polymer filter, for example, 255. It is -300 degreeC and 260-320 degreeC is preferable.

  The configuration of the polymer filter is not particularly limited, but a polymer filter in which a large number of leaf disk filters are arranged in a housing can be suitably used. The filter material of the leaf disk type filter may be any of a type in which a metal fiber nonwoven fabric is sintered, a type in which metal powder is sintered, a type in which several metal meshes are laminated, or a hybrid type in which they are combined. The sintered type is most preferred.

  The filtration accuracy by the polymer filter is not particularly limited, but is usually 15 μm or less, preferably 10 μm or less, more preferably 5 μm or less. When the filtration accuracy is 1 μm or less, the residence time of the resin composition becomes longer, so that the thermal degradation of the composition increases and the productivity of the resin film decreases. On the other hand, when the filtration accuracy exceeds 15 μm, it is difficult to remove foreign substances in the resin composition.

The filtration area with respect to the resin treatment amount per hour in the polymer filter is not particularly limited, and can be appropriately set according to the treatment amount of the resin composition. The filtration area is, for example, 0.001 to 0.15 m ² / (kg / h).

  The shape of the polymer filter is not particularly limited. For example, an inner flow type having a plurality of resin flow ports and a resin flow path in the center pole; an inner peripheral surface of the leaf disk filter at a plurality of vertices or faces And an external flow type having a resin flow path on the outer surface of the center pole. In particular, it is preferable to use an external flow type in which the resin stays are small.

  Although there is no restriction | limiting in particular in the residence time of the resin composition in a polymer filter, 20 minutes or less are preferable, 10 minutes or less are more preferable, and 5 minutes or less are further more preferable. Moreover, the filter inlet pressure and the filter outlet pressure at the time of filtration are, for example, 3 to 15 MPa and 0.3 to 10 MPa, respectively, and the pressure loss (pressure difference between the filter inlet pressure and the outlet pressure) is 1 MPa to 15 MPa. A range is preferred. When the pressure loss is 1 MPa or less, the resin composition tends to be biased in the flow path through the filter, and the quality of the obtained resin film tends to deteriorate. On the other hand, when the pressure loss exceeds 15 MPa, the polymer filter is easily damaged.

  What is necessary is just to set suitably the temperature of the resin composition introduce | transduced into a polymer filter according to the melt viscosity, for example, it is 250-300 degreeC, 255-300 degreeC is preferable and 260-300 degreeC is more preferable.

  The specific process of obtaining a resin film with few foreign substances and colored substances by filtration using a polymer filter is not particularly limited. For example, (1) a process in which a resin composition is formed and filtered in a clean environment, and then the resin composition is molded in a clean environment; (2) a resin composition having foreign matters or colored substances is cleaned A process in which the resin composition is subsequently molded in a clean environment after being filtered in an environment; (3) a process in which a resin composition having a foreign substance or a colored product is simultaneously filtered and molded in a clean environment; Etc. You may perform the filtration process of the resin composition by a polymer filter in multiple times for each process.

  When filtering the resin composition with the polymer filter, it is preferable to install a gear pump between the extruder and the polymer filter to stabilize the pressure of the resin composition in the filter.

The resin composition of the present invention is preferably extruded as it is after the production to obtain a resin film. Since heat history can be reduced as compared with the case where a resin film is formed by remelting the pellet obtained after pelletizing the resin composition, thermal deterioration of the resin composition can be suppressed. Moreover, in this method, since mixing of the foreign material from an environment can be suppressed, it can suppress that a foreign material exists in the obtained resin film, or coloring of the obtained resin film. A gear pump and a polymer filter are preferably arranged between the extruder and the T die.

  The resin film obtained by extrusion may be stretched as necessary. The type of stretching is not particularly limited, and may be uniaxial stretching or biaxial stretching. The mechanical strength of the resin film can be improved by stretching, and in some cases, birefringence can be imparted to the resin film. In addition, the resin composition of this invention can maintain optical isotropy after extending | stretching depending on the composition. The stretching temperature is not particularly limited, and a temperature in the vicinity of Tg of the resin composition is preferable. The draw ratio and the draw speed are not particularly limited.

  In order to stabilize the optical properties and mechanical properties of the resin film, heat treatment (annealing) may be performed as necessary after stretching.

  Hereinafter, the present invention will be described in more detail with reference to examples. The present invention is not limited to the examples shown below.

  Initially, the evaluation method of the resin composition sample produced in the present Example is shown.

[Glass-transition temperature]
The glass transition temperature (Tg) of each sample was determined in accordance with JIS K7121 regulations. Specifically, a differential scanning calorimeter (manufactured by Rigaku Corporation, DSC-8230) is used to raise a temperature of about 10 mg from room temperature to 200 ° C. (temperature increase rate: 20 ° C./min) in a nitrogen gas atmosphere. From the obtained DSC curve, it evaluated by the starting point method. Α-alumina was used as a reference. In addition, evaluation of Tg with respect to the film produced by the manufacture example was performed similarly.

[Light transmittance]
The light transmittance of each sample was obtained by forming the film with a thickness of 100 μm by extrusion molding, and then using the spectrophotometer (manufactured by Shimadzu Corporation, UV-3100) to determine the transmittance of the film with respect to light with wavelengths of 380 nm and 500 nm. It evaluated by measuring. A specific method for forming a 100 μm thick film from each sample will be described later.

  In addition, evaluation of the light transmittance with respect to the film produced by the manufacture example may be basically the same although the thickness of the film which is an evaluation object may differ.

[Foaming]
The foamability of each sample was evaluated as follows. First, the pellet-shaped resin composition was dried with a circulating hot air dryer (80 ° C., 5 hours), and 6 g of the dried pellets were put into a melt indexer defined in JIS K7210 whose temperature was controlled at 280 ° C. . After the charging, the melt indexer was held at 280 ° C. for 20 minutes, and then the molten resin composition was extruded into a strand shape with a load of 4.85 kg, and the foamed state of the formed strand was visually observed. When there are 20 or more bubbles having a diameter of 0.5 mm or more within 10 cm from the lower marked line of the melt indexer piston in the strand, “with foaming”, and when there are less than 20 bubbles, “no foaming” did.

[Sublimation]
The sublimation property of UVA in each sample was evaluated as follows. First, each sample was formed into a film having a thickness of 100 μm by extrusion, and a part (size: 1 cm × 3 cm) was cut out. Next, after the cut film was sealed in a test tube, it was heated in a metal bath at 150 ° C. for 10 hours. Next, after taking out the film from the test tube, 1 mL of chloroform was put into the test tube, and UVA sublimated from the film and adhered to the inner wall of the test tube was dissolved in chloroform. Next, chloroform in which UVA was dissolved was accommodated in a quartz cell having an optical path length of 1 cm, and the absorbance with respect to light having a wavelength of 350 nm was measured using an absorptiometer (manufactured by Shimadzu Corporation, UV-3100). The greater the UVA sublimation amount, the greater the measured absorbance.

[Spattering]
The degree of contamination of the molding apparatus when molding each sample was evaluated by measuring the amount of UVA attached to the cast roll (the metal roll with which the molten resin film extruded from the T-die first contacts). The amount of adhesion was evaluated as follows. First, after a resin film was continuously extrusion-molded for 1 hour by a molding apparatus equipped with a cast roll, a 10 cm × 10 cm range at the center of the roll was wiped off with a cellulose wiper dipped in chloroform. Next, the wiper used for wiping was immersed in 30 mL of chloroform, and UVA wiped off from the cast roll was dissolved in chloroform. Next, chloroform in which UVA was dissolved was accommodated in a quartz cell having an optical path length of 1 cm, and the absorbance with respect to light having a wavelength of 350 nm was measured using an absorptiometer (manufactured by Shimadzu Corporation, UV-3100). The greater the amount of UVA attached to the cast roll (ie, the higher the UVA scattering property), the greater the measured absorbance.

[Weight average molecular weight]
The weight average molecular weight of the acrylic resin was determined by gel permeation chromatography (GPC) under the following conditions.
System: Made by Tosoh Developing solvent: Chloroform (made by Wako Pure Chemical Industries, special grade), flow rate 0.6 ml / min
Standard sample: TSK standard polystyrene (Tosoh, PS-oligomer kit 12 type)
Column configuration (measurement side): Guard column (TSKGuardcolumn SuperH-H), two separation columns (TSKgel SuperHM-M) connected in series Column configuration (reference side): Reference column (TSKgel SuperH-RC)

[Content of lactone ring structure]
The content of the lactone ring structure in the acrylic resin was determined by the dynamic TG method as follows. First, a dynamic TG measurement was performed on an acrylic resin having a lactone ring structure, a weight reduction rate between 150 ° C. and 300 ° C. was measured, and the obtained value was defined as an actual weight reduction rate (X). . 150 ° C. is a temperature at which hydroxyl groups and ester groups remaining in the resin start a cyclization condensation reaction, and 300 ° C. is a temperature at which thermal decomposition of the resin begins. Separately, assuming that all the hydroxyl groups contained in the precursor polymer have undergone a dealcoholization reaction to form a lactone ring, the rate of weight loss due to the reaction (ie, dealcoholization of the precursor) The weight reduction rate assuming that the condensation reaction rate was 100%) was calculated and used as the theoretical weight reduction rate (Y). Specifically, the theoretical weight reduction rate (Y) can be determined from the content of the structural unit having a hydroxyl group involved in the dealcoholization reaction in the precursor. Note that the composition of the precursor was derived from the composition of the acrylic resin to be measured. Next, the dealcoholization reaction rate of the acrylic resin was determined by the formula [1- (actually measured weight reduction rate (X) / theoretical weight reduction rate (Y))] × 100 (%). In the acrylic resin to be measured, it is considered that a lactone ring structure is formed as much as the determined dealcoholization reaction rate. Therefore, the content of the structural unit having a hydroxyl group involved in the dealcoholization reaction in the precursor is multiplied by the obtained dealcoholization reaction rate and converted to the weight of the lactone ring structure, thereby containing the lactone ring structure in the acrylic resin. Rate.

As an example, the dealcoholization reaction rate of the resin (A-5) prepared in Comparative Example 1 described later is obtained. The molecular weight of methanol produced by the dealcoholization reaction is 32, and the content of the MHMA unit, which is a constituent unit having a hydroxyl group involved in the dealcoholization reaction, in the precursor (copolymer of MHMA and MMA) is 20.0. Since the molecular weight of the MHMA unit in terms of monomer is 116, the theoretical weight reduction rate (Y) of the resin (A) is (32/116) × 20 = 5.52%. On the other hand, since the actual weight loss rate (X) of the resin (A) was 0.18%, the dealcoholization reaction rate was 96.7% (= (1−0.18 / 5.52) × 100 ( %)).

  Next, the content rate of the lactone ring structure in the resin (A) is determined. Since the MHMA unit content in the precursor is 20.0%, the molecular weight of the MHMA unit in terms of monomer is 116, the dealcoholization reaction rate is 96.7%, and the formula weight of the lactone ring structure is 170. The content of the lactone ring structure in the resin (A) is 28.3% (= 20.0 × 0.967 × 170/116).

[Dynamic TG measurement]
The dynamic TG measurement of the acrylic resin was performed as follows.

The prepared acrylic resin pellets or the polymerization solution before the pellets were dissolved in tetrahydrofuran (THF) (or diluted with THF), and then the resin was precipitated using excess hexane or methanol. Next, the precipitate is vacuum dried (pressure 1.33 hPa, 80 ° C., 3 hours or more) to remove volatile components, and the obtained white solid resin is subjected to dynamic TG measurement under the following measurement conditions. Went.
Measuring device: Rigaku, Thermo Plus 2 TG-8120 Dynamic TG
Sample weight: 5-10mg
Temperature increase rate: 10 ° C./min Atmosphere: under nitrogen flow (200 ml / min) Measurement method: step-like isothermal control method (controlled at 60 to 500 ° C. with a weight reduction rate value of 0.005% / sec or less)

[Film thickness]
The thickness of the film was measured using a Digimatic Micrometer (manufactured by Mitutoyo Corporation).

[Change in turbidity of film]
The amount of change in turbidity of the film formed from each sample was evaluated as follows. First, each sample was formed into a film having a thickness of 100 μm by extrusion, and a part (size: 5 cm × 5 cm) was cut out. Next, the turbidity of the cut out film was measured using a turbidimeter (Nippon Denshoku Industries Co., Ltd., NDH-1001DP), and the measured value was taken as the initial value. Next, the cut film is left in a hot air dryer (made by Tabai Co., Ltd.) maintained at 100 ° C. for 200 hours, and then the turbidity of the film after being left is measured again to determine the amount of change from the initial value. Asked. As a factor that changes the turbidity of the film after molding, bleedout of UVA due to heat can be considered.

  In addition, the turbidity of the film produced by the manufacture example was also measured with the said turbidimeter.

(Example 1)
40 parts of methyl methacrylate (MMA), 10 parts of methyl 2- (hydroxymethyl) acrylate (MHMA), polymerization in a 30 L internal reaction vessel equipped with a stirrer, temperature sensor, cooling pipe and nitrogen introduction pipe As a solvent, 50 parts of toluene and 0.025 part of an antioxidant (Asahi Denka Kogyo Co., Ltd., ADK STAB 2112) were charged, and nitrogen was passed through this,
The temperature was raised to. When the reflux with the temperature increase started, 0.05 part of t-amyl peroxyisononanoate (manufactured by Arkema Yoshitomi, trade name: Luperox 570) was added as a polymerization initiator, and 0.10 part of t- While amyl peroxy isononanoate was added dropwise over 3 hours, solution polymerization was allowed to proceed under reflux at about 105 to 110 ° C., followed by further aging for 4 hours.

  Next, 0.05 part of 2-ethylhexyl phosphate (manufactured by Sakai Chemical Industry Co., Ltd., Phoslex A-8) is added to the resulting polymerization solution as a catalyst for the cyclization condensation reaction (cyclization catalyst). The cyclization condensation reaction was allowed to proceed for 2 hours under reflux at 0 ° C., and then the polymerization solution was heated for 30 minutes in an autoclave at 240 ° C. to further proceed the cyclization condensation reaction.

  Next, the obtained polymerization solution was subjected to a barrel temperature of 240 ° C., a rotation speed of 100 rpm, a degree of vacuum of 13.3 to 400 hPa (10 to 300 mmHg), a rear vent number of 1 and a fore vent number of 4 (first, first from the upstream side, Introduced into a vent type screw twin screw extruder (Φ = 29.75 mm, L / D = 30) at a processing rate of 2.0 kg / hour in terms of resin, Devolatilization was performed. At that time, a separately prepared UVA solution was added from the rear of the first vent at a charging rate of 0.03 kg / hour with a separately prepared mixed solution of antioxidant / cyclization catalyst deactivator. Ion exchange water was charged from behind the third vent at a charging rate of 05 kg / hr from the back of the third vent at a charging rate of 0.01 kg / hr.

  In the mixed solution of antioxidant / cyclization catalyst deactivator, 50 parts of antioxidant (Sumitizer GS manufactured by Sumitomo Chemical Co., Ltd.) and 35 parts of zinc octylate (manufactured by Nippon Kagaku Sangyo Co., Ltd., Nikka Octix) Zinc (3.6%) was dissolved in 200 parts of toluene.

  In the UVA solution, the CGL777MPA (manufactured by Ciba Specialty Chemicals, 80% active ingredient) having the ultraviolet absorber (molecular weight 958) represented by the above formula (8) as a main component and the ultraviolet absorber having a molecular weight of 773 and a molecular weight of 1142 as subcomponents is used. A solution prepared by dissolving 37.5 parts in 12.5 parts of toluene was used.

  Next, after the devolatilization is completed, the resin in the molten state left in the extruder is discharged from the tip of the extruder, pelletized by a pelletizer, and an acrylic resin having a lactone ring structure in the main chain (A-1) And a transparent resin composition pellet containing UVA (B) having a molecular weight of 700 or more. The weight average molecular weight of the resin (A-1) was 148,000, and the glass transition temperature (Tg) of the resin (A-1) and the resin composition was 128 ° C.

(Example 2)
Acrylic resin (A-1) having a lactone ring structure in the main chain and UVA (B) having a molecular weight of 700 or more are included in the same manner as in Example 1 except that the charging speed of the UVA solution is changed to 0.1 kg / hour. A transparent resin composition pellet was obtained. The glass transition temperature (Tg) of the resin composition was 127 ° C.

(Example 3)
In a reaction vessel having an internal volume of 30 L equipped with a stirrer, a temperature sensor, a cooling pipe and a nitrogen introduction pipe, 41.5 parts of methyl methacrylate (MMA) and 6 parts of methyl 2- (hydroxymethyl) acrylate (MHMA) 2.5 parts of 2- [2′-hydroxy-5′-methacryloyloxy] ethylphenyl] -2H-benzotriazole (trade name: RUVA-93, manufactured by Otsuka Chemical), 50 parts of toluene as a polymerization solvent, 0 0.025 part of an antioxidant (manufactured by Asahi Denka Kogyo Co., Ltd., Adeka Stub 2112) and 0.025 part of n-dodecyl mercaptan were charged as a chain transfer agent, and the temperature was raised to 105 ° C. through nitrogen. When the reflux with the temperature increase started, 0.05 part of t-amyl peroxyisononanoate (manufactured by Arkema Yoshitomi, trade name: Luperox 570) was added as a polymerization initiator, and 0.10 part of t- While amyl peroxy isononanoate was added dropwise over 3 hours, solution polymerization was allowed to proceed under reflux at about 105 to 110 ° C., followed by further aging for 4 hours.

  Next, 0.05 part of 2-ethylhexyl phosphate (manufactured by Sakai Chemical Industry Co., Ltd., Phoslex A-8) is added to the resulting polymerization solution as a catalyst for the cyclization condensation reaction (cyclization catalyst). The cyclization condensation reaction was allowed to proceed for 2 hours under reflux at 0 ° C., and then the polymerization solution was heated for 30 minutes in an autoclave at 240 ° C. to further proceed the cyclization condensation reaction. Next, 0.94 parts of the CGL777MPA as UVA (B) was mixed with the polymerization solution after the reaction proceeded.

Next, the obtained polymerization solution was subjected to a barrel temperature of 240 ° C., a rotation speed of 100 rpm, a degree of vacuum of 13.3 to 400 hPa (10 to 300 mmHg), a rear vent number of 1 and a forevent number of 4 (first and 2, third and fourth vents), a vent type screw twin screw extruder (Φ = 50.0 mm) in which a leaf disk type polymer filter (filtration accuracy 5 μ, filtration area 1.5 m ² ) is arranged at the tip. L / D = 30) was introduced at a treatment rate of 45 kg / hr in terms of resin amount, and devolatilization was performed. At that time, a separately prepared mixed solution of antioxidant / cyclization catalyst deactivator was charged at a rate of 0.68 kg / hour from the back of the first vent, and ion-exchanged water was charged at 0.22 kg / hour. Each was fed from behind the third vent at a speed. The same antioxidant / cyclization catalyst deactivator mixed solution as in Example 1 was used.

  Next, after completion of devolatilization, the resin in the hot melt state remaining in the extruder is discharged while being filtered through a polymer filter from the tip of the extruder, pelletized by a pelletizer, and has a lactone ring structure in the main chain A transparent resin composition pellet containing acrylic resin (A-2) and UVA (B) having a molecular weight of 700 or more was obtained. The weight average molecular weight of the resin (A-2) was 145000, and the glass transition temperature (Tg) of the resin (A-2) and the resin composition was 122 ° C.

Example 4
40 parts of methyl methacrylate (MMA), 10 parts of methyl 2- (hydroxymethyl) acrylate (MHMA), polymerization were carried out in a reaction vessel with an internal volume of 1000 L equipped with a stirrer, temperature sensor, cooling pipe and nitrogen introduction pipe. As a solvent, 50 parts of toluene and 0.025 part of an antioxidant (manufactured by Asahi Denka Kogyo Co., Ltd., Adeka Stub 2112) were charged, and the temperature was raised to 105 ° C. while introducing nitrogen. When the reflux with the temperature increase started, 0.05 part of t-amyl peroxyisononanoate (manufactured by Arkema Yoshitomi, trade name: Luperox 570) was added as a polymerization initiator, and 0.10 part of t- While amyl peroxy isononanoate was added dropwise over 3 hours, solution polymerization was allowed to proceed under reflux at about 105 to 110 ° C., followed by further aging for 4 hours.

  Next, 0.05 part of 2-ethylhexyl phosphate (manufactured by Sakai Chemical Industry Co., Ltd., Phoslex A-8) is added to the resulting polymerization solution as a catalyst for the cyclization condensation reaction (cyclization catalyst). The cyclization condensation reaction was allowed to proceed for 2 hours under reflux at 0 ° C., and then the polymerization solution was heated for 30 minutes in an autoclave at 240 ° C. to further proceed the cyclization condensation reaction. Next, 0.94 parts of the CGL777MPA as UVA (B) was mixed with the polymerization solution after the reaction proceeded.

Next, the obtained polymerization solution was subjected to a barrel temperature of 240 ° C., a rotation speed of 100 rpm, a degree of vacuum of 13.3 to 400 hPa (10 to 300 mmHg), a rear vent number of 1 and a forevent number of 4 (first and 2, third and fourth vents), a vent type screw twin screw extruder (Φ = 50.0 mm) in which a leaf disk type polymer filter (filtration accuracy 5 μ, filtration area 1.5 m ² ) is arranged at the tip. L / D = 30) was introduced at a treatment rate of 45 kg / hr in terms of resin amount, and devolatilization was performed. At that time, a separately prepared mixed solution of antioxidant / cyclization catalyst deactivator was charged at a rate of 0.68 kg / hour from the back of the first vent, and ion-exchanged water was charged at 0.22 kg / hour. Each was fed from behind the third vent at a speed. The same antioxidant / cyclization catalyst deactivator mixed solution as in Example 1 was used.

  Next, after completion of devolatilization, the resin in the hot melt state remaining in the extruder is discharged while being filtered through a polymer filter from the tip of the extruder, pelletized by a pelletizer, and has a lactone ring structure in the main chain A transparent resin composition pellet containing acrylic resin (A-3) and UVA (B) having a molecular weight of 700 or more was obtained. The weight average molecular weight of the resin (A-3) was 140,000, and the glass transition temperature (Tg) of the resin (A-3) and the resin composition was 128 ° C.

(Example 5)
40 parts of methyl methacrylate (MMA), 10 parts of methyl 2- (hydroxymethyl) acrylate (MHMA), polymerization were carried out in a reaction vessel with an internal volume of 1000 L equipped with a stirrer, temperature sensor, cooling pipe and nitrogen introduction pipe. As a solvent, 50 parts of toluene and 0.025 part of an antioxidant (manufactured by Asahi Denka Kogyo Co., Ltd., Adeka Stub 2112) were charged, and the temperature was raised to 105 ° C. while introducing nitrogen. When the reflux with the temperature increase started, 0.05 part of t-amyl peroxyisononanoate (manufactured by Arkema Yoshitomi, trade name: Luperox 570) was added as a polymerization initiator, and 0.10 part of t- While amyl peroxy isononanoate was added dropwise over 3 hours, solution polymerization was allowed to proceed under reflux at about 105 to 110 ° C., followed by further aging for 4 hours.

  Next, 0.05 part of 2-ethylhexyl phosphate (manufactured by Sakai Chemical Industry Co., Ltd., Phoslex A-8) is added to the resulting polymerization solution as a catalyst for the cyclization condensation reaction (cyclization catalyst). The cyclization condensation reaction was allowed to proceed for 2 hours under reflux at 0 ° C., and then the polymerization solution was heated for 30 minutes in an autoclave at 240 ° C. to further proceed the cyclization condensation reaction.

Next, the obtained polymerization solution was subjected to a barrel temperature of 240 ° C., a rotation speed of 100 rpm, a degree of vacuum of 13.3 to 400 hPa (10 to 300 mmHg), a rear vent number of 1 and a forevent number of 4 (first and 2, a third and a fourth vent), a side feeder is provided between the third vent and the fourth vent, and a leaf disk type polymer filter (filtration accuracy 5 μ, filtration area 1.5 m at the tip) ² ) was introduced into a vent type screw twin screw extruder (Φ = 50.0 mm, L / D = 30) at a processing rate of 45 kg / hour in terms of resin amount, and devolatilization was performed. At that time, a separately prepared UVA solution was prepared from the rear of the first vent at a charging rate of 0.68 kg / hour with a separately prepared mixed solution of antioxidant / cyclization catalyst deactivator. Ion exchange water was charged from behind the third vent at a charging rate of 25 kg / hour from the back of the third vent at a charging rate of 0.22 kg / hour. The same antioxidant / cyclization catalyst deactivator mixed solution and UVA solution were used as in Example 1. Further, styrene-acrylonitrile (AS) resin pellets (manufactured by Asahi Kasei Chemicals Co., Ltd., Stylac AS783) were charged from the side feeder at a charging speed of 5 kg / hour.

  Next, after devolatilization is completed, the resin in the molten state remaining in the extruder is discharged from the tip of the extruder while being filtered through a polymer filter, pelletized by a pelletizer, and acrylic having a lactone ring structure in the main chain. A transparent resin composition pellet containing resin (A-4) and UVA (B) having a molecular weight of 700 or more was obtained. The weight average molecular weight of the resin (A-4) was 145000, and the Tg of the resin (A-4) and the resin composition was 126 ° C.

(Comparative Example 1)
40 parts of methyl methacrylate (MMA), 10 parts of methyl 2- (hydroxymethyl) acrylate (MHMA), polymerization in a 30 L internal reaction vessel equipped with a stirrer, temperature sensor, cooling pipe and nitrogen introduction pipe As a solvent, 50 parts of toluene and 0.025 part of an antioxidant (Asahi Denka Kogyo Co., Ltd., ADK STAB 2112) were charged, and nitrogen was passed through this,
The temperature was raised to. When the reflux with the temperature increase started, 0.05 part of t-amyl peroxyisononanoate (manufactured by Arkema Yoshitomi, trade name: Luperox 570) was added as a polymerization initiator, and 0.10 part of t- While amyl peroxy isononanoate was added dropwise over 3 hours, solution polymerization was allowed to proceed under reflux at about 105 to 110 ° C., followed by further aging for 4 hours.

  Next, 0.05 part of 2-ethylhexyl phosphate (manufactured by Sakai Chemical Industry Co., Ltd., Phoslex A-8) is added to the resulting polymerization solution as a catalyst for the cyclization condensation reaction (cyclization catalyst). The cyclization condensation reaction was allowed to proceed for 2 hours under reflux at 0 ° C., and then the polymerization solution was heated for 30 minutes in an autoclave at 240 ° C. to further proceed the cyclization condensation reaction.

  Next, the obtained polymerization solution was subjected to a barrel temperature of 240 ° C., a rotation speed of 100 rpm, a degree of vacuum of 13.3 to 400 hPa (10 to 300 mmHg), a rear vent number of 1 and a fore vent number of 4 (first, first from the upstream side, Introduced into a vent type screw twin screw extruder (Φ = 29.75 mm, L / D = 30) at a processing rate of 2.0 kg / hour in terms of resin, Devolatilization was performed. At that time, a separately prepared mixed solution of antioxidant / cyclization catalyst deactivator was charged at a rate of 0.03 kg / hour from the back of the first vent, and ion-exchanged water was charged at 0.01 kg / hour. Each was fed from behind the third vent at a speed. The same solution as in Example 1 was used as the mixed solution of the antioxidant / cyclization catalyst deactivator.

  Next, after the devolatilization is completed, the resin in the hot melt state remaining in the extruder is discharged from the tip of the extruder, pelletized by a pelletizer, and an acrylic resin having a lactone ring structure in the main chain (A-5) Got. The weight average molecular weight of the resin (A-5) was 148,000.

  100 parts of the resin (A-5) thus obtained was dry blended with 1.5 parts of UVA having a benzotriazole skeleton (manufactured by ADEKA, Adeka Stub LA-31, molecular weight 659), and the resin (A-5) And a UVA resin composition were obtained. Tg of the resin (A-5) and the resin composition was 128 ° C.

(Comparative Example 2)
A resin composition of resin (A-5) and UVA was obtained in the same manner as in Example 1 except that the amount of UVA to be dry blended with resin (A-5) was changed to 3.0 parts. The Tg of the resin composition was 127 ° C.

(Comparative Example 3)
100 parts of the resin (A-5) obtained in Comparative Example 1 was dry blended with 1.5 parts of UVA (Sumitomo Chemical, Sumisorb 300, molecular weight 315) having a benzotriazole skeleton, and the resin (A-5) and UVA And a resin composition were obtained. The Tg of the resin composition was 128 ° C.

(Comparative Example 4)
To 100 parts of the resin (A-5) obtained in Comparative Example 1, 1.5 parts of UVA (CGL479 (TINUVIN479, manufactured by Ciba Specialty Chemicals, molecular weight 676)) having a skeleton in which one hydroxyphenyl group is bonded to triazine is dried. By blending, a resin composition of resin (A-5) and UVA was obtained. The Tg of the resin composition was 128 ° C.

  The results of evaluating the above properties for the resin compositions obtained in Examples 1 to 5 and Comparative Examples 1 to 4 are shown in Table 1 below.

  The resin film having a thickness of 100 μm used for the evaluation of characteristics was produced by extrusion molding the resin compositions obtained in the respective examples and comparative examples. A specific extrusion method is as follows.

In Examples 4 and 5, first, the obtained resin composition was introduced into a single-screw extruder with a vent having a barrier flight type screw at a treatment rate of 30 kg / hour, and suction was performed from a vent port at a pressure of 10 mmHg. The resin composition was melt kneaded. Thereafter, the resin composition in the melted state in the extruder is filtered by a gear pump through a leaf disk type polymer filter having a filtration accuracy of 5 μm and a filtration area of 0.75 m ² , and the filtered composition is T-die (width 700 mm). Were discharged onto a cooling roll having a temperature of 90 ° C. to obtain a resin film having a thickness of 100 μm. At this time, the temperature of the cylinder, gear pump, polymer filter, and T-die was set to 265 ° C.

  In each of the examples and comparative examples other than Examples 4 and 5, first, the obtained resin composition was introduced into a single screw extruder having a cylinder diameter of 20 mm, and the resin composition was melted. Thereafter, the resin composition in a heat-melted state in the extruder was discharged from a T die (width 120 mm) onto a cooling roll having a temperature of 110 ° C. to obtain a resin film having a thickness of 100 μm. At this time, the temperature of the cylinder and the T-die was 280 ° C.

  As shown in Table 1, in the resin compositions of the examples, UVA sublimation and scattering properties at the time of molding are suppressed as compared with the comparative examples while realizing a high glass transition temperature, ultraviolet absorption ability and visible light transmission. did it. Moreover, in the resin composition of an Example, generation | occurrence | production of the foaming at the time of shaping | molding was suppressed.

  The amount of change in turbidity of the resin film prepared from the resin composition of the example was smaller than that of the resin film prepared from the resin composition of the comparative example (excluding Comparative Example 1). In the resin films produced from the resin compositions of the examples, it is considered that UVA bleed-out due to heat after film formation was suppressed as compared with the comparative examples.

(Production Example 1)
The pellet of the resin composition produced in Example 3 was melt-extruded from a coat hanger type T die having a width of 150 mm using a twin-screw extruder having a screw diameter of 20 mmφ to produce a resin film having a thickness of about 160 μm. .

  Next, the obtained unstretched resin film was cut into a square having a side length of 127 mm, and then set on a chuck of a corner stretch type biaxial stretching test apparatus (X6-S, manufactured by Toyo Seiki Seisakusho). The distance between the chucks was 110 mm both vertically and horizontally. The set resin film was preheated at 160 ° C. for 3 minutes, and then the first uniaxial stretching at a stretching ratio of 2.0 times was performed in a stretching time of 1 minute. At this time, the width direction of the film (the direction orthogonal to the stretching direction) was not shrunk.

  After stretching, the uniaxially stretched resin film was quickly taken out from the test apparatus and cooled. Next, the cooled film was cut into a square having a side length of 97 mm, and the second stage of uniaxial stretching was performed in the same manner as the uniaxial stretching. The stretching direction of the second stage was a direction orthogonal to the stretching direction of the first stage, and the distance between the chucks when setting the film on the test apparatus was 80 mm both vertically and horizontally. As in the first stage, preheating was performed at 160 ° C. for 3 minutes, the draw ratio was 2.0 times, and the draw time was 1 minute. Moreover, the width direction of the film was not shrunk during stretching.

  After the second stage of stretching, the resin film was quickly removed from the test apparatus and cooled. When the physical properties of the biaxially stretchable resin film thus obtained were measured, the thickness was 40 mm, the haze (turbidity) was 0.3%, the glass transition temperature was 128 ° C., and the transmittance for light at 380 nm was The transmittance for light of 5.8% and 500 nm was 92.2%.

(Production Example 2)
A polyvinyl alcohol (PVA) unstretched film having a saponification degree of 99% and a thickness of 75 μm was washed with water at room temperature, and then uniaxially stretched in the MD direction (stretching ratio 5 times). The stretched film is immersed in an iodine / potassium iodide aqueous solution (iodine concentration of 0.5%, potassium iodide concentration of 5%) while maintaining the tension state, and the dichroic dye is adsorbed on the PVA film. It was. Subsequently, the film on which the dye was adsorbed was immersed in a boric acid / potassium iodide aqueous solution at a temperature of 50 ° C. (boric acid concentration: 10%, potassium iodide concentration: 5%) to perform a crosslinking treatment for 5 minutes, A polarizer based on a PVA stretched film was obtained.

(Production Example 3)
In a four-necked flask equipped with a thermometer, stirrer, cooler, dropping funnel and nitrogen gas inlet tube, 200 parts of toluene and 100 parts of isopropyl alcohol as solvents, 80 parts of butyl methacrylate and 25 parts of butyl acrylate as monomers Then, 75 parts of methyl methacrylate and 20 parts of methacrylic acid were added, and then the whole was heated to 85 ° C. with stirring while introducing nitrogen gas into the flask.

Next, a mixture consisting of 0.005 part of 2,2′-sobisisobutyronitrile (trade name: ABN-R, manufactured by Nippon Hydrazine Kogyo) and 10 parts of toluene as a polymerization initiator was placed in the flask over 7 hours. Divided into two. Next, after aging at 85 ° C. for 3 hours, the mixture was cooled to room temperature to obtain a polymer having a weight average molecular weight of 90000.

  Next, after raising the temperature of the flask containing the polymer to 40 ° C., 20 parts of ethyleneimine was dropped into the flask over 1 hour, and the temperature was maintained for 1 hour. The temperature was raised to 75 ° C. and aging was performed for 4 hours. Next, a distillation apparatus was set in the flask and heated under reduced pressure to discharge isopropyl alcohol and unreacted ethyleneimine out of the system. Finally, the easy-adhesion layer coating composition (D-1) containing an ethyleneimine-modified acrylic polymer (having an amino group in the side chain) is prepared by adjusting the concentration of the non-volatile component to 10% with toluene. It was.

(Production Example 4)
In a reactor equipped with a thermometer, a nitrogen gas inlet tube and a stirrer, while introducing nitrogen gas into the reactor, 367.2 parts of 1,4-butanediol, 166 parts of isophthalic acid and 0.05 part of dibutyltin oxide were added. The mixture was melted with heating and stirring, and a condensation reaction was performed at 200 ° C. for 8 hours until the acid value became 1.1. Next, the reactor is cooled to 120 ° C., 584 parts of adipic acid and 268 parts of 2,2-dimethylolpropionic acid are added, and then the temperature is raised again to 170 ° C., and the reaction is carried out at that temperature for 23 hours. A polyester polyol having a value of 102.0 and an acid value of 93.5 was obtained. Next, 55 parts of the obtained polyester polyol was dehydrated at 100 ° C. under reduced pressure, cooled to 60 ° C., and 6.58 parts of 1,4-butanediol were further added, and the whole was sufficiently stirred and mixed. Next, after adding 35.17 parts of hexamethylene diisocyanate, the reactor was heated to 100 ° C. and reacted at this temperature for 4.5 hours to obtain an NCO-terminated urethane prepolymer. After completion of the reaction, the mixture was cooled to 40 ° C. and 96.75 parts of acetone was added to dilute the whole to obtain a prepolymer solution. Next, a prepolymer solution prepared by dissolving 7.04 parts of piperazine and 10.19 parts of triethylamine in 245.19 parts of water in advance is gradually poured into the solution to gradually extend and neutralize the chain. went. After removing acetone from this reaction product at 50 ° C. under reduced pressure, water is added, and a polyester ionomer type urethane resin having a non-volatile component concentration of 30%, a viscosity of 60 mPa · s / 25 ° C., and a pH of 7.1. An aqueous dispersion was obtained. Next, 20 parts of the obtained aqueous dispersion and 1.2 parts of self-emulsifying polyisocyanate are dispersed in 14.8 parts of deionized water, and an adhesive (D-2) having a non-volatile component concentration of 20% is obtained. Obtained.

(Production Example 5)
MMA 8000 g, MHMA 2000 g and toluene 10000 g as a polymerization solvent were charged into a reaction vessel having an internal volume of 30 L equipped with a stirrer, a temperature sensor, a cooling pipe and a nitrogen introduction pipe, and the temperature was raised to 105 ° C. while passing nitrogen through the reactor. When the reflux accompanying the temperature rise began, 10.0 g of t-amylperoxyisonononanoate was added as a polymerization initiator, and a solution comprising 20.0 g of t-amylperoxyisonononanoate and 100 g of toluene was added. While dropping over time, solution polymerization was allowed to proceed under reflux at about 105 to 110 ° C., and further aging was performed for 4 hours. The polymerization reaction rate was 96.6%, and the content (weight ratio) of MHMA in the obtained polymer was 20.0%.

  Next, 10 g of stearyl phosphate / distearyl phosphate mixture (Phoslex A-18, manufactured by Sakai Chemical Industry Co., Ltd.) as a cyclization catalyst is added to the resulting polymerization solution, and the mixture is refluxed at about 80 to 100 ° C. for 5 hours. The cyclization condensation reaction was allowed to proceed.

Next, the obtained polymerization solution was subjected to a barrel type screw twin screw extruder having a barrel temperature of 260 ° C., a rotation speed of 100 rpm, a degree of vacuum of 13.3 to 400 hPa (10 to 300 mmHg), a rear vent number of 1, and a forevent number of 4. (Φ = 29.75 mm, L / D = 30) was introduced at a treatment rate of 2.0 kg / hour in terms of resin amount, and cyclization condensation reaction and devolatilization were performed in the extruder. Next, after completion of devolatilization, the resin in the molten state left in the extruder is discharged from the tip of the extruder, pelletized by a pelletizer, and transparent pellets made of an acrylic resin having a lactone ring structure in the main chain Got. The weight average molecular weight of this resin is 148,000, the melt flow rate (based on JIS K7120, the test temperature is 240 ° C., the load is 10 kg, the same applies to the following production examples) is 11.0 g / 10 min, glass transition The temperature was 130 ° C.

  Next, the obtained pellets and AS resin (product name: Toyo AS AS20, manufactured by Toyo Styrene Co., Ltd.) were kneaded using a single screw extruder (φ = 30 mm) at a weight ratio of pellet / AS resin = 90/10. As a result, a transparent pellet (E) having a glass transition temperature of 127 ° C. was obtained.

  Next, the obtained pellet (E) was melt-extruded from a coat hanger type T die having a width of 150 mm using a twin-screw extruder having a 20 mmφ screw to obtain a film having a thickness of about 160 μm.

  Next, the obtained film was cut into a square having a side of 97 mm, and then set on the chuck of the stretching test apparatus used in Production Example 1. The distance between the chucks was 80 mm both vertically and horizontally. After the set film was preheated at 160 ° C. for 3 minutes, simultaneous biaxial stretching was performed in a stretching time of 1 minute so that the stretching ratios in the longitudinal and transverse directions (MD / TD directions) were both 2.0 times. After stretching, the simultaneously biaxially stretched film was quickly removed from the test apparatus and cooled.

  The biaxially stretchable film thus obtained has a thickness of 40 μm, an in-plane retardation of 2 nm, a thickness direction retardation of 3 nm, a total light transmittance of 92%, a haze of 0.3%, and a glass transition. The temperature was 127 ° C.

  The in-plane retardation and the retardation in the thickness direction are values per 100 μm of film thickness with respect to light having a wavelength of 589 nm, and were evaluated using a retardation measuring apparatus (manufactured by Oji Scientific Instruments, KOBRA-WR). The total light transmittance was evaluated using a turbidimeter (Nippon Denshoku Industries Co., Ltd., NDH-1001DP). The method for measuring the phase difference and the total light transmittance is the same in the following production examples. Moreover, the value of retardation is a value per 100 μm of film thickness with respect to light having a wavelength of 589 nm in all of the following production examples.

(Production Example 6)
A reaction vessel having an internal volume of 30 L equipped with a stirrer, a temperature sensor, a cooling pipe, and a nitrogen introduction pipe was charged with 7950 g of MMA, 1500 g of MHMA, 550 g of styrene (St), and 10,000 g of toluene as a polymerization solvent. The temperature was raised to 105 ° C. When the temperature reached 105 ° C., 12 g of t-amyl peroxyisonanoate was added as a polymerization initiator, and a solution consisting of 24 g of t-amyl peroxyisonanoate and 136 g of toluene was added dropwise over 2 hours. However, the solution polymerization was allowed to proceed under reflux at about 105 to 110 ° C., and further aging was performed for 4 hours.

  Next, 10 g of octyl phosphate (Phoslex A-8, manufactured by Sakai Chemical Industry Co., Ltd.) is added to the resulting polymerization solution as a cyclization catalyst, and the cyclization condensation reaction is allowed to proceed at about 120 ° C. for 5 hours under pressure. It was.

Next, the obtained polymerization solution was placed in a vent type screw twin screw extruder (φ = 29.75 mm, L / D = 30) having 1 rear vent and 4 forevents in an amount of 2.0 kg in terms of resin amount. It was introduced at a processing speed of / hour, and devolatilization was performed at a barrel temperature of 240 ° C., a rotation speed of 120 rpm, and a degree of vacuum of 13.3 to 400 hPa (10 to 300 mmHg). In the case of devolatilization, zinc octylate (manufactured by Nippon Kagaku Sangyo Co., Ltd., Nikka octix zinc) is used as a foaming inhibitor so that the concentration is 1400 ppm (weight basis) with respect to the resin obtained in the form of a toluene solution. Injected from between the second and third for vents.

  Place a water tank filled with filtered cooling water at the tip of the twin-screw extruder, cool the strand discharged from the tip of the extruder in the water tank, and then introduce the cooled strand into the pelletizer. A transparent pellet (F) made of an acrylic resin having a lactone ring structure in the main chain was obtained. A clean space was provided from the die at the tip of the extruder to the pelletizer so that the environmental cleanliness was 5000 or less. The obtained resin had a weight average molecular weight of 137,000 and a glass transition temperature of 125 ° C. Further, the number of foreign matters having a particle diameter of 20 μm or more contained per 100 g of pellets as observed with an optical microscope was 35.

  Next, the obtained pellet (F) was melt-extruded from a coat hanger type T die having a width of 150 mm using a twin screw extruder having a 20 mmφ screw to obtain a film having a thickness of about 160 μm.

  Next, the obtained film was cut into a square having a side of 97 mm, and then set on the chuck of the stretching test apparatus used in Production Example 1. The distance between the chucks was 80 mm both vertically and horizontally. The set film was preheated at 155 ° C. for 3 minutes, and then subjected to simultaneous biaxial stretching with a stretching time of 1 minute so that the stretching ratios in the longitudinal and transverse directions (MD / TD directions) were both 2.0 times. After stretching, the simultaneously biaxially stretched film was quickly removed from the test apparatus and cooled.

  The biaxially stretchable film thus obtained has a thickness of 40 μm, an in-plane retardation of 3 nm, a thickness direction retardation of 2 nm, a total light transmittance of 92%, a haze of 0.4%, and a glass transition. The temperature was 125 ° C.

(Production Example 7)
Into a reaction vessel having an internal volume of 30 L equipped with a stirrer, a temperature sensor, a cooling pipe and a nitrogen introduction pipe, 5000 g of MMA, 3000 g of MHMA, 2000 g of benzyl methacrylate (BzMA) and 10,000 g of toluene as a polymerization solvent were charged. The temperature was raised to 105 ° C. while passing nitrogen through. At the beginning of the reflux with temperature rise, t-amyl peroxy isononanoate (trade name: Lupazole 570, manufactured by Atofina Yoshitomi) as a polymerization initiator was added at 6.0 g, and t-amyl peroxy isonononate 12 While a polymerization initiator solution consisting of 0.0 g and 100 g of toluene was added dropwise over 6 hours, solution polymerization was carried out under reflux at about 105 to 110 ° C., followed by aging for 2 hours.

  Next, 10 g of octyl phosphate / dioctyl phosphate mixture (manufactured by Sakai Chemical Industry, Phoslex A-8) is added to the resulting polymerization solution as a cyclization catalyst, and the mixture is refluxed at about 80 to 105 ° C. for 2 hours. After allowing the cyclization condensation reaction to proceed, the polymerization solution was heated for 1.5 hours under pressure (up to 1.6 MPa as a gauge pressure) by an autoclave at 240 ° C. to further proceed the cyclization condensation reaction.

  Next, the polymerization solution obtained was a vent type screw twin screw extruder having a barrel temperature of 250 ° C., a rotation speed of 100 rpm, a degree of vacuum of 13.3 to 400 hPa (10 to 300 mmHg), a rear vent number of 1 and a forevent number of 4 (Φ = 29.75 mm, L / D = 30) was introduced at a treatment rate of 2.0 kg / hour in terms of resin amount, and devolatilization was performed.

  Next, after completion of devolatilization, the resin in the molten state left in the extruder is discharged from the tip of the extruder, pelletized by a pelletizer, and transparent pellets made of an acrylic resin having a lactone ring structure in the main chain (G) was obtained. The weight average molecular weight of the obtained resin was 130,000, and the glass transition temperature was 135 ° C.

(Production Example 8)
In a pressure-resistant reaction vessel, 70 parts of deionized water, 0.5 part of sodium pyrophosphate, 0.2 part of potassium oleate, 0.005 part of ferrous sulfate, 0.2 part of dextrose, p-menthane hydroperoxide After adding a reaction mixture consisting of 1 part and 28 parts of 1,3-butadiene, the whole was heated to 65 ° C. and polymerized for 2 hours. Next, 0.2 part of p-hydroperoxide was added to the reaction product in the container, and then 72 parts of 1,3-butadiene, 1.33 parts of potassium oleate and 75 parts of deionized water were continuously added over 2 hours. Dripped. The reaction was continued for 21 hours from the start of polymerization to obtain a butadiene-based rubber polymer latex (average particle size 0.240 μm).

  Next, in a polymerization vessel equipped with a cooler and a stirrer, 50 parts of the latex as a solid content, 120 parts of deionized water, 1.5 parts of potassium oleate, and 0.6 parts of sodium formaldehyde sulfoxylate (SFS) And the inside of the polymerization vessel was sufficiently replaced with nitrogen gas. Next, after raising the temperature in the container to 70 ° C., a mixed monomer solution consisting of 36.5 parts of styrene and 13.5 parts of acrylonitrile, 0.27 parts of cumene hydroxyperoxide and 20.0 parts of deionized water The polymerization reaction was advanced while continuously dropping the polymerization initiator solution consisting of 2 over 2 hours. After completion of the dropwise addition of the mixed monomer solution and the polymerization initiator solution, the temperature in the container was raised to 80 ° C. and polymerization was continued for another 2 hours. Then, after the temperature in the container was cooled to 40 ° C., the obtained polymerization solution was passed through a 300-mesh wire mesh to obtain an emulsion polymerization solution of elastic organic fine particles.

  Next, the obtained emulsion polymerization solution was salted out and coagulated with calcium chloride, further washed with water and dried to obtain powdery elastic organic fine particles (P). The average particle size of the obtained elastic organic fine particles (P) was 0.260 μm. For measurement of the average particle size of the elastic organic fine particles, a particle size distribution measuring device (Submicron Particle Sizer NICOMP380) manufactured by NICOMP was used.

  The elastic organic fine particles (P) thus obtained and the pellets (G) produced in Production Example 7 are fed using a feeder so that the weight ratio is (P) / (G) = 30/70. The mixture was kneaded at 280 ° C. using a twin screw extruder having a cylinder diameter of 20 mm to obtain pellets (H) containing elastic organic fine particles.

  Next, the obtained pellet (H) was melt-extruded from a coat hanger type T die having a width of 150 mm using a twin-screw extruder having a 20 mmφ screw to produce a film having a thickness of about 140 μm. The in-plane retardation of the produced unstretched film was 3 nm.

  Next, the obtained unstretched film was uniaxially stretched at 136 ° C. using an autograph (manufactured by Shimadzu Corporation, AGS-100D) to obtain a uniaxially stretchable film having a thickness of 88 μm. The draw ratio was 2.5 times and the draw speed was 400% / min. The obtained stretched film had an in-plane retardation of 476 nm (measured 419 nm), a thickness direction retardation of 246 nm, a total light transmittance of 92%, and a haze of 0.6%.

(Production Example 9)
7000 g of MMA, 3000 g of MHMA, and 12000 g of toluene as a polymerization solvent were charged into a reaction vessel having an internal volume of 30 L equipped with a stirrer, a temperature sensor, a cooling pipe, and a nitrogen introduction pipe, and the temperature was raised to 105 ° C. through nitrogen. Allowed to warm. When refluxing with a rise in temperature began, 6.0 g of t-amylperoxyisononanoate (manufactured by Atofina Yoshitomi, Lupazole 570) was added as a polymerization initiator, and 12.0 g of t-amylperoxyisonononanoate was added. While a solution consisting of 100 g of toluene was added dropwise over 2 hours, solution polymerization was allowed to proceed under reflux at about 105 to 110 ° C., followed by further aging for 4 hours.

  Next, 20 g of an octyl phosphate / dioctyl phosphate mixture (manufactured by Sakai Chemical Industry Co., Ltd., trade name: Phoslex A-8) is added to the resulting polymerization solution as a cyclization catalyst. The cyclization condensation reaction was allowed to proceed for 2 hours. Next, the whole is diluted by adding 4000 g of methyl ethyl ketone, and then the polymerization solution is heated for 1.5 hours under pressure (up to about 2 MPa in terms of gauge pressure) by an autoclave at 240 ° C. to further carry out the cyclization condensation reaction. Proceeded.

  Next, after the obtained polymerization solution was diluted with methyl ethyl ketone, (1) 26.5 g of zinc octylate (manufactured by Nippon Chemical Industry Co., Ltd., Nikka Octix zinc 18%) and IRGANOX 1010 (manufactured by Ciba Specialty Chemicals) as an antioxidant 2.2 g and ADK STAB AO-412S (manufactured by ADEKA) 2.2 g and a solution composed of 61.6 g of toluene as a solvent were charged at a rate of 20 g / hr, (2) the barrel temperature was 250 ° C., Except that, transparent pellet (I) made of an acrylic resin having a lactone ring structure in the main chain was obtained in the same manner as in Production Example 5.

  When the obtained pellet (I) was measured for dynamic TG, a weight loss of 0.21% was detected. The obtained resin had a weight average molecular weight of 110,000, a melt flow rate of 8.7 g / 10 minutes, and a glass transition temperature of 142 ° C.

Next, the obtained pellet (I) was extruded under the following conditions using a single-screw extruder having a cylinder diameter of 20 mm to produce an unstretched film (J) having a thickness of about 400 μm.
Extrusion conditions-cylinder temperature: 280 ° C
Die: Coat hanger type, width 150mm, temperature 290 ° C
Casting: Keep two rolls with gloss, the first roll and the second roll at 130 ° C.

  In addition, the obtained film (J) is strip | belt shape, the width direction in the said film is a TD direction, and the direction (direction orthogonal to the TD direction in a film surface) where a film is extended is MD direction.

  The in-plane retardation of the obtained unstretched film (J) is 0.3 nm (measured 1.3 nm), the thickness direction retardation is 0.5 nm (measured 2.2 nm), the thickness is 433 μm, and the glass transition temperature. Was 142 ° C.

(Production Example 10)
The unstretched film (J) produced in Production Example 9 was successively biaxially stretched using the stretching test apparatus used in Production Example 1.

  Specifically, the film (J) was cut into a square having a side length of 127 mm, and then set on the chuck of the test apparatus so that the MD direction was the stretching direction. The distance between the chucks was 110 mm both vertically and horizontally. The set resin film was preheated at 165 ° C. for 3 minutes, and then the first uniaxial stretching at a stretching ratio of 3.0 was performed for a stretching time of 10 seconds. At this time, the width direction (TD direction) of the film was not shrunk.

After stretching, the uniaxially stretched resin film was quickly taken out from the test apparatus and cooled. Next, the cooled film was cut into a square having a side length of 97 mm, and the second stage of uniaxial stretching was performed in the same manner as the uniaxial stretching. The stretching direction of the second stage was a direction (TD direction) perpendicular to the stretching direction of the first stage, and the distance between the chucks when setting the film on the test apparatus was 80 mm both vertically and horizontally. Preheating was performed at 145 ° C. for 3 minutes, the stretching ratio was 2.2 times, and the stretching time was 1 minute. Moreover, at the time of extending | stretching, it was made not to shrink | contract in the direction (MD direction) orthogonal to the extending | stretching direction in a film similarly to the extending | stretching of the 1st step.

  The biaxially stretchable film thus obtained has an in-plane retardation of 282 nm (measured 135 nm), a thickness direction retardation of 307 nm (measured 148 nm), a thickness of 48 μm, a total light transmittance of 93%, and a haze. Was 0.3% and the glass transition temperature was 142 ° C.

(Production Example 11)
The unstretched film (J) produced in Production Example 9 was successively biaxially stretched under different stretching conditions from Production Example 10. Specifically, the first stage stretching temperature was 150 ° C., the stretching ratio was 2.5 times, and the stretching time was 1 minute. The second stage stretching temperature was 150 ° C., the stretching ratio was 2.5 times, and the stretching time was 1 minute.

  The biaxially stretchable film thus obtained has an in-plane retardation of 142 nm (measured 91 nm), a thickness direction retardation of 203 nm (measured 130 nm), a thickness of 64 μm, a total light transmittance of 93%, and a haze. Was 0.2% and the glass transition temperature was 142 ° C.

(Production Example 12)
The unstretched film (J) produced in Production Example 9 was simultaneously biaxially stretched under different stretching conditions from Production Example 10. Preheating was performed at 155 ° C. for 3 minutes, the stretching temperature was 155 ° C., the stretching ratio was 2.5 times in both the TD and MD directions, and the stretching time was 1 minute.

  After stretching, the simultaneously biaxially stretched resin film was quickly taken out from the test apparatus and cooled. The biaxially stretched film thus obtained has an in-plane retardation of 21 nm (measured 8 nm), a thickness direction retardation of 213 nm (measured 81 nm), a thickness of 38 μm, a total light transmittance of 93%, and a haze. Was 0.2% and the glass transition temperature was 142 ° C.

(Production Examples 13 to 22)
Using the resin film of 100 μm thickness formed from the resin composition prepared in Examples 2 and 4 and the resin film prepared in Production Examples 1, 5, 6, 8, and 10 to 12 as a polarizer protective film, A polarizing plate was prepared by bonding to both sides of the polarizer produced in Production Example 2, and the adhesive strength between the polarizer and the polarizer protective film in the obtained polarizing plate and the heat and humidity resistance of the obtained polarizing plate were evaluated. .

  The polarizing plate was produced as follows.

  First, the easy-adhesion layer coating composition (D-1) produced in Production Example 3 was applied to the surface of the polarizer protective film to be bonded to the polarizer with a bar coater, and the composition ( D-1) was dried. Next, after applying the adhesive (D-2) produced in Production Example 4 on the dried composition (D-1), the polarizer is brought into contact with the adhesive (D-2). Bonded to a protective film. Joining was performed by wet lamination while extruding excess adhesive using a pressure roller. The surface of the polarizer to which the polarizer protective film is bonded is referred to as “A surface”.

Next, another polarizer protective film is applied to the surface (B surface) opposite to the A surface of the polarizer in the same manner as described above, and the easy-adhesion layer coating composition (D-1) and the adhesive (D-2). ) And then bonded by wet lamination. Next, the whole is dried in a hot air dryer at 60 ° C. for 10 hours, and then dried in an oven maintained at 50 ° C. for 15 hours, so that the polarizer is sandwiched between a pair of polarizer protective films. Got. The thickness of the adhesive (D-2) layer after drying was 50 μm. Table 2 below shows the types of the polarizer protective film bonded to each of the A and B surfaces of the polarizing plate, and the results of evaluating the adhesive strength and heat and humidity resistance of the obtained polarizing plate. In addition, the evaluation method of adhesive strength and heat-and-humidity resistance is as follows.

[Adhesive strength]
After fixing the produced polarizing plate on a polypropylene plate with a double-sided tape, an attempt was made to peel the polarizer protective film from the polarizer. The adhesive strength between the polarizer and the polarizer protective film was evaluated in five stages according to the peeled state at that time. The evaluation criteria are as follows.
1: Easy peeling by pulling the end of the film by hand.
2: Peel when the cutter blade is inserted into the joint surface.
3: The blade of the cutter is inserted into the joint surface between the two, and further peeled when force is applied to the blade.
4: Even if the cutter blade is inserted into the joint surface between the two, only a small piece is peeled off.
5: The blade of the cutter cannot be inserted into the joint surface between the two and does not peel off.

[Heat resistance]
The prepared polarizing plate was cut into a size of 2.5 × 5 cm, and then immersed in warm water at 60 ° C. for 4 hours, thereby attempting to peel off the polarizer and the polarizer protective film. The heat and humidity resistance of the polarizing plate was evaluated in three stages depending on the state of peeling at that time. The evaluation criteria are as follows.
Good (O): No peeling.
Possible (△): There is some peeling.
Impossible (x): The entire surface peels off.

  As shown in Table 2, in all the production examples, excellent adhesive strength and heat and humidity resistance were realized. Moreover, all the polarizer protective films joined to the A surface of the polarizer are the polarizer protective films of the present invention, and since the acrylic resin constituting each film has a ring structure in the main chain, Production Example 13 The polarizing plate produced by ~ 22 has high ultraviolet-absorbing ability, heat resistance, and optical characteristics.

  According to the present invention, it is a resin composition containing a thermoplastic acrylic resin and an ultraviolet absorber, and exhibits excellent heat resistance based on a high glass transition temperature of 110 ° C. or higher, and even at the time of molding at a high temperature, Generation | occurrence | production of foaming, bleed-out, etc. is suppressed, and the resin composition with few generation | occurrence | production of the problem by transpiration of UVA can be provided.

It is a schematic diagram which shows an example of the structure of the image display part in the image display apparatus of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 3, 5, 7 Polarizer protective film 2, 6 Polarizer 4 Liquid crystal cell 8 Backlight 9 Polarizing plate 10 Polarizing plate 11 Image display part

Claims (14)

Including a thermoplastic acrylic resin and an ultraviolet absorber having a molecular weight of 700 or more,
A thermoplastic resin composition having a glass transition temperature of 110 ° C. or higher.   The thermoplastic resin composition according to claim 1, wherein the ultraviolet absorber has a hydroxyphenyltriazine skeleton.   The thermoplastic resin composition according to claim 1, wherein the acrylic resin has a ring structure in the main chain.   The thermoplastic resin composition according to claim 3, wherein the ring structure is at least one selected from a lactone ring structure, a glutaric anhydride structure, a glutarimide structure, an N-substituted maleimide structure, and a maleic anhydride structure.   The thermoplastic resin composition according to claim 3, wherein the structure is a lactone ring structure.   The thermoplastic resin composition according to claim 1, further comprising a copolymer of a vinyl cyanide monomer and an aromatic vinyl monomer.   The thermoplastic resin composition according to claim 1, wherein the acrylic resin has a styrene unit as a constituent unit.   A resin molded article comprising the thermoplastic resin composition according to claim 1.   The resin molded product according to claim 8, which is a sheet or a film. When the film has a thickness of 100 μm, the transmittance of light having a wavelength of 380 nm and 500 nm measured in accordance with JIS K7361: 1997 is 1% or less and 90% or more, respectively.
When a film having a thickness of 100 μm and a size of 1 cm × 3 cm is obtained, a volatile component obtained by heating the film at 150 ° C. for 10 hours is dissolved in a 1 mL volume solvent, and the obtained solution is a quartz cell having an optical path length of 1 cm. The resin molded product according to claim 8, wherein the absorbance to light having a wavelength of 350 nm measured by an absorptiometer is less than 0.05.   A polarizer protective film comprising the thermoplastic resin composition according to claim 1.   A polarizing plate comprising a polarizer and the polarizer protective film according to claim 11.   An image display device comprising the polarizing plate according to claim 12.   A method for producing a resin molded product, wherein the thermoplastic resin according to claim 1 is extruded to obtain a molded product.

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