JP2007297619A - Thermoplastic resin composition, and extruded film or sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermoplastic resin composition having both high transparency and high heat resistance enabling the composition to be used for various kinds of optical materials, and also having ultraviolet-absorbing ability; and to provide an extruded film or sheet. <P>SOLUTION: The thermoplastic resin composition is composed of at least (A) an acrylic resin and (B) an ultraviolet-absorbing resin having ≤10% light transmittance at 380 nm wavelength in 50 μm thickness, and has (a) ≥110°C glass transition temperature and (b) ≥80% light transmittance at 500 nm wavelength and ≤30% light transmittance at 380 nm wavelength in 50 μm thickness. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a thermoplastic resin composition and an extruded film or sheet. More specifically, the present invention relates to a thermoplastic resin composition suitably used as an optical material required to have excellent optical properties, and an extruded film or sheet comprising the same.

  Acrylic resins represented by PMMA (polymethylmethacrylate) are excellent in optical properties such as high light transmittance, and are well-balanced in mechanical strength, molding processability, and surface hardness. Was made. However, when exposed to light containing ultraviolet rays, there was a problem that transparency was lowered due to yellowing. For this reason, generally UV absorbers are added to acrylic resins, but these UV absorbers are low in molecular weight, so bleed-out is likely to occur, and the addition amount decreases due to transpiration during molding, There were various problems such as a decrease in ultraviolet absorption ability and contamination of the production process.

  As an attempt to solve such a problem, a method in which an ultraviolet absorbing monomer is used alone or copolymerized is known (for example, see Patent Document 1). However, since general acrylic resins have low heat resistance, the resins themselves have poor shape stability at high temperatures, and there has been only a method of kneading, laminating or coating with other resins.

  On the other hand, a lactone ring-containing polymer obtained by subjecting a polymer having a hydroxyl group and an ester group in a molecular chain to a lactone cyclization condensation reaction is known as an acrylic resin having both transparency and heat resistance. (For example, refer to Patent Documents 2 to 4.) Moreover, the polymer which copolymerized N-substituted maleimide and methacrylic acid ester is also known (for example, refer patent document 5). However, since these polymers have high heat resistance, the molding temperature is higher than that of a general acrylic resin, and transpiration due to a low molecular weight UV absorber and the contamination of the production process due to this are more likely to occur.

JP-A-5-170941 (page 1-2) JP 2000-230016 (page 1-2) JP 2001-151814 A (page 1-2) JP 2002-120326 A (page 1-2) Japanese Patent Laid-Open No. 9-324016 (page 1-2)

  The present invention has been made in view of the above situation, and an object of the present invention is to provide a thermoplastic resin composition, an extruded film, or a sheet that have both high transparency and heat resistance, and have ultraviolet absorption ability.

  As a result of various studies on amorphous thermoplastic resins, the present inventors have found that acrylic resins and ultraviolet absorbing resins are excellent in compatibility. In particular, the present inventors have found that an acrylic resin having a lactone ring structure is excellent in transparency, heat resistance, and compatibility with an ultraviolet absorbing resin.

That is, the present invention comprises at least (A) an acrylic resin,
(B) a composition comprising an ultraviolet absorbing resin having a light transmittance of 380 nm at a thickness of 50 μm and a wavelength of 10% or less, wherein the composition has (a) a glass transition temperature of 110 ° C. or higher,
(B) The light transmittance at a wavelength of 500 nm at a thickness of 50 μm is 80% or more,
The light transmittance at a wavelength of 380 nm is 30% or less,
This is a thermoplastic resin composition.

  Furthermore, the present invention is characterized in that the acrylic resin (A) constituting the thermoplastic resin composition has a ring structure in the main chain.

  Furthermore, the present invention is characterized in that the acrylic resin (A) constituting the thermoplastic resin composition has a lactone ring structure.

  Furthermore, the present invention is an extruded film or sheet comprising the thermoplastic resin composition.

  The thermoplastic resin composition of the present invention provides a resin composition that has both high transparency and heat resistance, and has ultraviolet absorbing ability.

  In the present application, the main component is defined as containing 50% by weight or more, “part by mass” and “part by weight” are synonymous, and N to M are defined as including N and N or more and including M and M or less. Moreover, the measurement of the light transmittance in this application means the transmittance | permeability of the designated wavelength at the time of shape | molding to the film of designated thickness.

[Acrylic resin]
The acrylic resin used in the present invention is a resin obtained by polymerizing acrylic acid, methacrylic acid and a derivative thereof as a main component, and a derivative thereof, and is not particularly limited unless the effects of the present invention are impaired. A publicly known acrylic resin can be used. Preferable specific examples of the derivatives of acrylic acid and methacrylic acid include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, n-butyl (meth) acrylate, and (meth) acrylic. T-butyl acid, n-hexyl (meth) acrylate, cyclohexyl (meth) acrylate, chloromethyl (meth) acrylate, 2-chloroethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, (meth ) 3-hydroxypropyl acrylate, 2,3,4,5,6-pentahydroxyhexyl (meth) acrylate, 2,3,4,5-tetrahydroxypentyl (meth) acrylate, and the like. One of them may be contained alone or two or more of them may coexist. Among these, methyl methacrylate is most preferable in that the resin obtained by polymerization is excellent in optical properties and thermal stability.

  The acrylic resin according to the present invention preferably has a weight average molecular weight of 1,000 to 300,000, more preferably 5,000 to 250,000, still more preferably 10,000 to 200,000, and particularly preferably 50. , 000-200,000.

  The acrylic resin according to the present invention preferably has a 5% weight loss temperature in thermogravimetric analysis (TG) of 280 ° C. or higher, more preferably 290 ° C. or higher, and further preferably 300 ° C. or higher. The 5% weight loss temperature in thermogravimetric analysis (TG) is an index of thermal stability, and if it is less than 280 ° C., sufficient thermal stability may not be exhibited.

  The glass transition temperature (Tg) of the acrylic resin according to the present invention is preferably 110 ° C. or higher, more preferably 115 ° C. or higher, further preferably 120 ° C. or higher, more preferably 125 ° C. or higher, and most preferably 130 ° C. or higher. It is. Here, the glass transition temperature is a temperature at which polymer molecules start micro-Brownian motion, and there are various measurement methods. In the present invention, a differential scanning calorimeter (DSC) is used in accordance with ASTM-D-3418. It is defined as the temperature obtained by the midpoint method. Although a plurality of glass transition temperatures may be observed, in the present invention, a main transition temperature having a larger endothermic amount is adopted.

  The acrylic thermoplastic resin according to the present invention preferably has a ring structure in the main chain (also referred to as a polymer main skeleton or a molecular chain) from the viewpoint of heat resistance. In order to introduce a ring structure into the main chain, N-substituted maleimides such as phenylmaleimide, cyclohexylmaleimide, and methylmaleimide may be copolymerized, or a ring formation reaction may be performed after polymerization to produce a lactone ring structure, glutaric acid. An anhydride structure, glutarimide structure, and maleimide structure may be introduced. Especially, the structure which does not contain a nitrogen atom from the point of the difficulty of coloring (yellowing) of a film is preferable. Moreover, it is preferable that it has a lactone ring structure from a moldability and an optical characteristic, and a lactone ring structure is general formula (in terms of good copolymerizability with (meth) acrylic acid esters, such as methyl methacrylate. The structure represented by 1) is preferable.

(In the formula, R1, R2, and R3 are the same or different and each represents a hydrogen atom or an organic residue having 1 to 20 carbon atoms. The organic residue may contain an oxygen atom.)
In this specification, the organic residue specifically includes an alkyl group having 1 to 20 carbon atoms such as a methyl group, an ethyl group, and a propyl group; an ethenyl group, a propenyl group, and the like having 1 to 1 carbon atoms. 20 unsaturated aliphatic hydrocarbon groups; aromatic hydrocarbon groups having 1 to 20 carbon atoms, such as phenyl groups and naphthyl groups; hydrogens of the alkyl groups, unsaturated hydrocarbon groups, and aromatic hydrocarbon groups A group in which one or more atoms are substituted with a hydroxyl group; a group in which one or more hydrogens in the alkyl group, the unsaturated hydrocarbon group, or the aromatic hydrocarbon group are substituted with a carboxyl group; the alkyl group, A group in which one or more hydrogens of a saturated hydrocarbon group or an aromatic hydrocarbon group are substituted with an ether group; one or more hydrogens in the alkyl group, the unsaturated hydrocarbon group or the aromatic hydrocarbon group are esters. Substituted with a group It is preferable that. That is, an alkyl group having 1 to 20 carbon atoms, an unsaturated aliphatic hydrocarbon group having 1 to 20 carbon atoms, an aromatic hydrocarbon group having 1 to 20 carbon atoms, or at least one of these groups , A hydroxyl group, a carboxyl group, an ether group, or a group substituted with an ester group.

  The content of the lactone ring structure in the lactone ring-containing polymer is preferably 5 to 90% by weight, more preferably 10 to 70% by weight, still more preferably 10 to 60% by weight, and particularly preferably 10 to 50% by weight. . If the content of the lactone ring structure represented by the above formula (1) is less than 5% by weight, the heat resistance, solvent resistance and surface hardness may be insufficient, which is not preferable.

  The lactone ring-containing polymer may have a structure other than the structure represented by the above formula (1). Examples of the structure other than the lactone ring structure represented by the above formula (1) include, for example, a (meth) acrylic acid ester, a hydroxyl group-containing monomer, and an unsaturated carboxylic acid as described later as a method for producing a lactone ring-containing polymer. A polymer structural unit (repeating unit) constructed by polymerizing at least one selected from monomers represented by the following formula (2) is preferred.

(In the formula, R 4 represents a hydrogen atom or a methyl group, and X represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group, an —OAc group, a —CN group, a —CO—R 5 group, or —C— O-R6 group is represented, Ac group represents an acetyl group, R5 and R6 represent a hydrogen atom or a C1-C20 organic residue.)
The content ratio of the structure other than the lactone ring structure represented by the above formula (1) in the lactone ring-containing polymer structure is a polymer structural unit (repeated structural unit) constructed by polymerizing (meth) acrylic acid ester. In this case, it is preferably 10 to 95% by weight, more preferably 10 to 90% by weight, still more preferably 40 to 90% by weight, and particularly preferably 50 to 90% by weight. In the case of the polymer structural unit to be constructed (repeating structural unit), preferably 0 to 30% by weight, more preferably 0 to 20% by weight, still more preferably 0 to 15% by weight, particularly preferably 0 to 10% by weight. It is. In the case of a polymer structural unit (repeating structural unit) constructed by polymerizing an unsaturated carboxylic acid, preferably 0 to 30% by weight, more preferably 0 to 20% by weight, still more preferably 0 to 15% by weight, Particularly preferably, it is 0 to 10% by weight. In the case of a polymer structural unit (repeating structural unit) constructed by polymerizing the monomer represented by the general formula (2a), it is preferably 0 to 30% by weight, more preferably 0 to 20% by weight, still more preferably. Is 0 to 15% by weight, particularly preferably 0 to 10% by weight.

The method for producing the lactone ring-containing polymer is not particularly limited. Preferably, the polymer (g) having a hydroxyl group and an ester group in the molecular chain is obtained by a polymerization step, and then the obtained polymer ( It is obtained by carrying out a lactone cyclization condensation reaction step for introducing a lactone ring structure into the polymer by heat-treating g).
In the polymerization step, a polymer having a hydroxyl group and an ester group in the molecular chain is obtained by conducting a polymerization reaction of a monomer component containing a monomer represented by the following formula (3).

(In the formula, R7 and R8 each independently represent a hydrogen atom or an organic residue having 1 to 20 carbon atoms.)
Examples of the monomer represented by the above formula (3) include methyl 2- (hydroxymethyl) acrylate, ethyl 2- (hydroxymethyl) acrylate, isopropyl 2- (hydroxymethyl) acrylate, 2- ( Hydroxymethyl) normal butyl acrylate, tertiary butyl 2- (hydroxymethyl) acrylate, and the like. Among these, methyl 2- (hydroxymethyl) acrylate and 2- (hydroxymethyl) ethyl acrylate are particularly preferable, and methyl 2- (hydroxymethyl) acrylate is particularly preferable in terms of high heat resistance improvement effect. As the monomer represented by the above formula (3), only one type may be used, or two or more types may be used.

  The content ratio of the monomer represented by the above formula (3) in the monomer component used in the polymerization step is preferably 5 to 90% by weight, more preferably 10 to 70% by weight, and still more preferably 10 to 70% by weight. 60% by weight, particularly preferably 10 to 50% by weight. When the content of the monomer represented by the above formula (3) in the monomer component to be used in the polymerization step is more than 90% by weight, gelation may occur during polymerization or lactone cyclization, or obtained. The molding processability of the polymer may be poor, which is not preferable.

  The monomer component provided in the polymerization step may contain a monomer other than the monomer represented by the above formula (3). Examples of such monomers include (meth) acrylic acid esters, hydroxyl group-containing monomers, unsaturated carboxylic acids, and monomers represented by the above formula (2). Only one type of monomer other than the monomer represented by the above formula (3) may be used, or two or more types may be used in combination.

  The (meth) acrylic acid ester is not particularly limited as long as it is a (meth) acrylic acid ester other than the monomer represented by the above formula (3). For example, methyl acrylate, ethyl acrylate, acrylic acid acrylic esters such as n-butyl, isobutyl acrylate, t-butyl acrylate, cyclohexyl acrylate, benzyl acrylate; methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, methacryl Methacrylic acid esters such as t-butyl acid, cyclohexyl methacrylate, benzyl methacrylate; and the like. These may be used alone or in combination of two or more. Among these, methyl methacrylate is particularly preferable from the viewpoint of excellent heat resistance and transparency.

  When (meth) acrylic acid ester other than the monomer represented by the above formula (3) is used, the content ratio in the monomer component to be subjected to the polymerization step is sufficient to exert the effect of the present invention. The amount is preferably 10 to 95% by weight, more preferably 10 to 90% by weight, and still more preferably 40 to 90% by weight.

  The hydroxyl group-containing monomer is not particularly limited as long as it is a hydroxyl group-containing monomer other than the monomer represented by the above formula (3). For example, α-hydroxymethyl styrene, α-hydroxyethyl styrene, Examples thereof include 2-hydroxyethyl acrylate and 2-hydroxyethyl methacrylate, and these may be used alone or in combination of two or more.

  In the case of using a hydroxyl group-containing monomer other than the monomer represented by the above formula (3), the content ratio in the monomer component to be subjected to the polymerization step is sufficient to exert the effect of the present invention. Preferably, it is 0 to 30% by weight, more preferably 0 to 20% by weight, still more preferably 0 to 15% by weight, and particularly preferably 0 to 10% by weight.

  Examples of the unsaturated carboxylic acid include acrylic acid, methacrylic acid, crotonic acid, α-substituted acrylic acid, α-substituted methacrylic acid, etc., and these may be used alone or in combination of two types. May be. Among these, acrylic acid and methacrylic acid are particularly preferable in that the effects of the present invention are sufficiently exhibited.

  When using unsaturated carboxylic acid, the content ratio in the monomer component to be subjected to the polymerization step is preferably 0 to 30% by weight, more preferably 0 to 20% by weight, in order to sufficiently exhibit the effects of the present invention. %, More preferably 0 to 15% by weight, particularly preferably 0 to 10% by weight.

  Examples of the monomer represented by the formula (2) include styrene, vinyl toluene, α-methyl styrene, acrylonitrile, methyl vinyl ketone, ethylene, propylene, vinyl acetate, and the like. May be used, or two or more of them may be used in combination. Among these, styrene and α-methylstyrene are particularly preferable in that the effects of the present invention are sufficiently exhibited.

  When using the monomer represented by the above formula (2), the content ratio in the monomer component to be subjected to the polymerization step is preferably 0 to 30% by weight in order to sufficiently exhibit the effects of the present invention. More preferably, it is 0 to 20% by weight, still more preferably 0 to 15% by weight, and particularly preferably 0 to 10% by weight.

The form of the polymerization reaction for polymerizing the monomer component to obtain a polymer having a hydroxyl group and an ester group in the molecular chain is preferably a polymerization form using a solvent, and solution polymerization is particularly preferred.
The polymerization temperature and polymerization time vary depending on the type of monomer used, the ratio of use, etc., but preferably the polymerization temperature is 0 to 150 ° C. and the polymerization time is 0.5 to 20 hours, more preferably polymerization. The temperature is 80 to 140 ° C. and the polymerization time is 1 to 10 hours.

  In the case of a polymerization form using a solvent, the polymerization solvent is not particularly limited. For example, aromatic hydrocarbon solvents such as toluene, xylene, and ethylbenzene; ketone solvents such as methyl ethyl ketone and methyl isobutyl ketone; ether solvents such as tetrahydrofuran Etc., and only one of these may be used, or two or more may be used in combination. Moreover, since the residual volatile matter of the lactone ring containing polymer finally obtained will increase when the boiling point of the solvent to be used is too high, a thing with a boiling point of 50-200 degreeC is preferable.

  During the polymerization reaction, a polymerization initiator may be added as necessary. The polymerization initiator is not particularly limited. For example, t-amylperoxy-2-ethylhexanoate, t-amylperoxyisononanoate, t-amylperoxyacetate, cumene hydroperoxide, diisopropylbenzene hydroperoxide , Organic peroxides such as di-t-butyl peroxide, lauroyl peroxide, benzoyl peroxide, t-butyl peroxyisopropyl carbonate; 2,2'-azobis (isobutyronitrile), 1,1'-azobis (Cyclohexanecarbonitrile), azo compounds such as 2,2′-azobis (2,4-dimethylpareronitrile), and the like. These may be used alone or in combination of two or more. May be. What is necessary is just to set the usage-amount of a polymerization initiator suitably according to the combination of the monomer to be used, reaction conditions, etc., and it does not specifically limit. Further, a chain transfer agent may be used for controlling the molecular weight of the polymer, and examples thereof include alkyl mercaptans such as butyl mercaptan, octyl mercaptan, dodecyl mercaptan, α-styrene dimer, and the like.

  When performing the polymerization, it is preferable to control the concentration of the produced polymer in the polymerization reaction mixture to be 70% by weight or less in order to suppress gelation of the reaction solution. Specifically, when the concentration of the produced polymer in the polymerization reaction mixture exceeds 70% by weight, it is preferable to add a polymerization solvent to the polymerization reaction mixture and control it to be 70% by weight or less. . The concentration of the produced polymer in the polymerization reaction mixture is more preferably 60% by weight or less, still more preferably 55% by weight or less. Note that if the concentration of the polymer in the polymerization reaction mixture is too low, the productivity is lowered. Therefore, the concentration of the polymer in the polymerization reaction mixture is preferably 10% by weight or more, and more preferably 20% by weight or more. It is more preferable.

  The form in which the polymerization solvent is appropriately added to the polymerization reaction mixture is not particularly limited, and the polymerization solvent may be added continuously or intermittently. By controlling the concentration of the produced polymer in the polymerization reaction mixture in this way, the gelation of the reaction solution can be more sufficiently suppressed, and in particular, to increase the lactone ring content and improve the heat resistance. Even when the ratio of the hydroxyl group to the ester group in the molecular chain is increased, gelation can be sufficiently suppressed. The polymerization solvent to be added may be the same type of solvent used during the initial charging of the polymerization reaction or may be a different type of solvent, but is the same as the solvent used during the initial charging of the polymerization reaction. It is preferable to use different types of solvents. Further, the polymerization solvent to be added may be only one type of solvent or a mixed solvent of two or more types.

  The polymerization reaction mixture obtained when the above polymerization step is completed usually contains a solvent in addition to the obtained polymer, but it is necessary to completely remove the solvent and take out the polymer in a solid state. Rather, it is preferably introduced into the subsequent lactone cyclization condensation step in a state containing a solvent. If necessary, after taking out in a solid state, a solvent suitable for the subsequent lactone cyclization condensation step may be added again.

  The polymer obtained in the polymerization step is a polymer (g) having a hydroxyl group and an ester group in the molecular chain, and the weight average molecular weight of the polymer (g) is preferably 1,000 to 300,000, More preferably, it is 5,000-250,000, More preferably, it is 10,000-200,000, Most preferably, it is 50,000-200,000. The polymer (g) obtained in the polymerization step is subjected to heat treatment in the subsequent lactone cyclization condensation step, whereby a lactone ring structure is introduced into the polymer to become a lactone ring-containing polymer.

In the reaction for introducing a lactone ring structure into the polymer (g), a hydroxyl group and an ester group or a carboxyl group existing in the molecular chain of the polymer (g) are cyclized and condensed to form a lactone ring structure by heating. The reaction is a by-product of alcohol or water. By forming the lactone ring structure in the molecular chain of the polymer (in the main skeleton of the polymer), high heat resistance is imparted. If the reaction rate of the cyclization condensation reaction leading to the lactone ring structure is insufficient, the heat resistance will not be improved sufficiently, or the condensation reaction will occur during the molding by the heat treatment during molding, and the resulting alcohol will be in the molded product It is not preferable because it is present as bubbles or silver streaks.
The lactone ring-containing polymer obtained in the lactone cyclization condensation step preferably has a lactone ring structure represented by the above formula (1).

  The method for heat-treating the polymer (g) is not particularly limited. For example, a known method can be used, and the polymerization reaction mixture containing the solvent obtained by the polymerization step may be heat-treated as it is. Moreover, you may heat-process using a ring-closing catalyst as needed in presence of a solvent. Further, the heat treatment can be performed using a heating furnace or reaction apparatus having a vacuum apparatus or a devolatilizing apparatus for removing volatile components, an extruder having a devolatilizing apparatus, or the like.

  When the cyclization condensation reaction is performed, in addition to the polymer (g), another thermoplastic resin may coexist. Further, when performing the cyclization condensation reaction, if necessary, an esterification catalyst or a transesterification catalyst such as p-toluenesulfonic acid generally used as a catalyst for the cyclization condensation reaction may be used. Organic carboxylic acids such as propionic acid, benzoic acid, acrylic acid, and methacrylic acid may be used as a catalyst. Moreover, you may use a basic compound, organic carboxylate, carbonate, etc. When a basic compound, organic carboxylate, carbonate, or the like is used, it may be as described in JP-A-61-254608 or JP-A-61-261303.

  In carrying out the cyclization condensation reaction, it is preferable to use an organic phosphorus compound as a catalyst. When an organophosphorus compound is used as a catalyst, it may be as disclosed in JP-A-2001-151814. By using an organophosphorus compound as a catalyst, the cyclization condensation reaction rate can be improved, and coloring of the resulting lactone ring-containing polymer can be greatly reduced. Furthermore, by using an organophosphorus compound as a catalyst, it is possible to suppress a decrease in molecular weight that can occur when a devolatilization step described later is used in combination, and to impart excellent mechanical strength.

  The amount of the catalyst used in the cyclization condensation reaction is not particularly limited, but is preferably 0.001 to 5% by weight, more preferably 0.01 to 2.5% by weight, based on the polymer (g). More preferably, it is 0.01 to 1% by weight, particularly preferably 0.05 to 0.5% by weight. If the amount of the catalyst used is less than 0.001% by weight, the reaction rate of the cyclization condensation reaction may not be sufficiently improved. On the other hand, if it exceeds 5% by weight, it may cause coloring or heavy load. This is not preferable because it is difficult to melt and form by cross-linking of the coalescence.

  The addition timing of the catalyst is not particularly limited, and it may be added at the beginning of the reaction, during the reaction, or both.

  It is preferable to carry out the cyclization condensation reaction in the presence of a solvent and to use a devolatilization step in combination with the cyclization condensation reaction. In this case, a mode in which the devolatilization step is used throughout the cyclization condensation reaction and a mode in which the devolatilization step is not used throughout the entire cyclization condensation reaction and are used only in a part of the process. In the method using the devolatilization step in combination, the alcohol produced as a by-product in the condensation cyclization reaction is forcibly devolatilized and removed, so that the equilibrium of the reaction is advantageous for the production side.

  The devolatilization step refers to a step of removing volatile components such as a solvent and residual monomer and alcohol produced as a by-product by a cyclocondensation reaction leading to a lactone ring structure, if necessary under reduced pressure heating conditions. If this removal treatment is insufficient, the residual volatile components in the produced resin increase, resulting in problems such as coloration due to alteration during molding, and molding defects such as bubbles and silver streaks.

  In the case of a form in which a devolatilization step is used throughout the cyclization condensation reaction, the apparatus to be used is not particularly limited. It is preferable to use an extruder equipped with a vent or the above-mentioned devolatilizer and the above-mentioned extruder in series, and it is more preferable to use a devolatilizer comprising a heat exchanger and a devolatilizer or a vented pusher. preferable.

  The reaction treatment temperature for the field using the devolatilizer composed of the heat exchanger and the devolatilizer is preferably in the range of 150 to 350 ° C, more preferably in the range of 200 to 300 ° C. If the reaction treatment temperature is lower than 150 ° C., the cyclization condensation reaction may be insufficient and the remaining volatile content may be high, and if it is higher than 350 ° C., coloring or decomposition may occur.

  When using a devolatilizer comprising the heat exchanger and the devolatilizer, the pressure during the reaction treatment is preferably in the range of 931 to 1.33 hPa (700 to 1 mmHg), and 798 to 66.5 hPa (600 to 50 mmHg). A range is more preferred. When the pressure is lower than 931 hPa, there is a problem that volatile components including alcohol easily remain, and when the pressure is lower than 1.33 hPa, there is a problem that industrial implementation becomes difficult.

  When using the extruder with a vent, one or a plurality of vents may be used, but it is preferable to have a plurality of vents.

  In the case of using the vented extruder, the reaction treatment temperature is preferably in the range of 150 to 350 ° C, more preferably in the range of 200 to 300 ° C. If the temperature is lower than 150 ° C, the cyclization condensation reaction may be insufficient and the residual volatile matter may increase. If the temperature is higher than 350 ° C, coloring or decomposition may occur.

  In the case of using the extruder with a vent, the pressure during reaction treatment is preferably in the range of 931 to 1.33 hPa (700 to 1 mmHg), and more preferably in the range of 798 to 13.3 hPa (600 to 10 mmHg). When the pressure is higher than 931 hPa, there is a problem that volatile components including alcohol easily remain, and when the pressure is lower than 1.33 hPa, there is a problem that industrial implementation becomes difficult.

  In the case of using the devolatilization step throughout the entire cyclization condensation reaction, the physical properties of the lactone ring-containing polymer obtained may be deteriorated under severe heat treatment conditions, as described later. It is preferable to use a reaction catalyst and use a vented extruder or the like under the mildest conditions possible.

  In the case of using the devolatilization step throughout the entire cyclization condensation reaction, preferably, the polymer (g) obtained in the polymerization step is introduced into the cyclization condensation reactor system together with the solvent. If necessary, it may be passed through the reactor system such as a vented extruder once again.

  You may perform the form used together only in a part of process, without using a devolatilization process over the whole process of cyclization condensation reaction. For example, the apparatus for producing the polymer (g) is further heated, and if necessary, a part of the devolatilization step is used together to advance the cyclization condensation reaction to some extent in advance, and then the devolatilization step. Is a form in which a cyclization condensation reaction is simultaneously used to complete the reaction.

  In the form of using the devolatilization step throughout the cyclization condensation reaction described above, for example, when the polymer (g) is heat-treated at a high temperature close to 250 ° C. or higher using a twin-screw extruder. Depending on the difference in thermal history, partial decomposition or the like may occur before the cyclization condensation reaction occurs, and the physical properties of the resulting lactone ring-containing polymer may be deteriorated. Therefore, if the cyclization condensation reaction is allowed to proceed to some extent before the cyclization condensation reaction using the devolatilization step at the same time, the latter reaction conditions can be relaxed and the physical properties of the resulting lactone ring-containing polymer deteriorated. Is preferable. As a particularly preferred embodiment, the devolatilization step is started after a lapse of time from the start of the cyclization condensation reaction, that is, the hydroxyl group and ester group present in the molecular chain of the polymer (g) obtained in the polymerization step. A mode in which the cyclization condensation reaction rate obtained by the cyclization condensation reaction in advance is increased to some extent, and then the cyclization condensation reaction using the devolatilization step simultaneously is performed. Specifically, for example, a cyclization condensation reaction is allowed to proceed to a certain reaction rate in the presence of a solvent in advance using a kettle-type reactor, and then a reactor equipped with a devolatilizer, for example, a heat The form which completes a cyclization condensation reaction with the devolatilizer which consists of an exchanger and a devolatilization tank, the extruder with a vent, etc. is mentioned. Particularly in this form, it is more preferable that a catalyst for the cyclization condensation reaction is present.

  As described above, the hydroxyl group and ester group present in the molecular chain of the polymer (g) obtained in the polymerization step are subjected to a cyclization condensation reaction in advance to increase the cyclization condensation reaction rate to some extent. The method of carrying out the cyclization condensation reaction using the steps at the same time is a preferred form in obtaining a lactone ring-containing polymer in the present invention. With this form, a lactone ring-containing polymer having a higher glass transition temperature, a higher cyclization condensation reaction rate, and excellent heat resistance can be obtained.

  The reactor that can be employed in the cyclization condensation reaction that is performed in advance before the cyclization condensation reaction using the devolatilization process at the same time is not particularly limited, but preferably an autoclave, a kettle reactor, a heat exchanger, and a devolatilization tank A vented extruder suitable for a cyclocondensation reaction using a devolatilization step at the same time can also be used. More preferred are autoclaves and kettle reactors. However, even when using a reactor such as an extruder with a vent, by adjusting the temperature condition, barrel condition, screw shape, screw operating condition, etc. It is possible to carry out the cyclization condensation reaction in the same state as the reaction state in the kettle reactor.

In the case of the cyclization condensation reaction carried out in advance before the cyclization condensation reaction using the devolatilization step at the same time, preferably, a mixture containing the polymer (g) obtained in the polymerization step and the solvent is used as (i). Examples thereof include a method in which a catalyst is added and subjected to a heat reaction, (ii) a method in which a catalyst is heated and reacted, and a method in which the above (i) or (ii) is performed under pressure.
The “mixture containing the polymer (g) and the solvent” introduced into the cyclization condensation reaction in the lactone cyclization condensation step may be the polymerization reaction mixture obtained in the polymerization step as it is, or once It means that a solvent suitable for the cyclocondensation reaction may be added again after removing the solvent.

  The solvent that can be re-added in the cyclization condensation reaction that is carried out in advance before the cyclization condensation reaction simultaneously used in the devolatilization step is not particularly limited, and examples thereof include aromatic hydrocarbons such as toluene, xylene, and ethylbenzene; Ketones such as methyl ethyl ketone and methyl isobutyl ketone: chloroform, DMSO (dimethyl sulfoxide), tetrahydrofuran and the like may be used, but the same solvent as that used in the polymerization step is preferable.

  Examples of the catalyst to be added in the above method (i) include esterification catalysts or transesterification catalysts such as p-toluenesulfonic acid, basic compounds, organic carboxylates, and carbonates that are generally used. Is preferably the above-described organophosphorus compound.

  The addition timing of the catalyst is not particularly limited, and it may be added at the beginning of the reaction, during the reaction, or both. The amount of the catalyst to be added is not particularly limited, but is preferably 0.001 to 5% by weight, more preferably 0.01 to 2.5% by weight, and still more preferably 0.01 to the weight of the polymer (g). -1% by weight, particularly preferably 0.05-0.5% by weight.

  The heating temperature and heating time of the above method (i) are not particularly limited, but the heating temperature is preferably room temperature or higher, more preferably 50 ° C. or higher, and the heating time is preferably 1 to 20 hours, more preferably. Is 2 to 10 hours. If the heating temperature is low or the heating time is short, the cyclization condensation reaction rate is lowered, which is not preferable. Further, if the heating time is too long, the resin may be colored or decomposed, which is not preferable.

  Examples of the method (ii) include a method of heating the polymerization reaction mixture obtained in the polymerization step as it is using a pressure-resistant kettle or the like. The heating temperature is preferably 100 ° C. or higher, more preferably 150 ° C. or higher. The heating time is preferably 1 to 20 hours, more preferably 2 to 10 hours. If the heating temperature is low or the heating time is short, the cyclization condensation reaction rate is lowered, which is not preferable. Further, if the heating time is too long, the resin may be colored or decomposed, which is not preferable.

  In both the above methods (i) and (ii), there is no problem even under pressure depending on conditions. In the case of the cyclization condensation reaction performed in advance before the cyclization condensation reaction using the devolatilization process at the same time, there is no problem even if a part of the solvent volatilizes naturally during the reaction.

  The weight reduction rate between 150 and 300 ° C. in the dynamic TG measurement at the end of the cyclization condensation reaction performed in advance before the cyclization condensation reaction simultaneously using the devolatilization step, that is, before the start of the devolatilization step is: It is preferably 2% or less, more preferably 1.5% or less, and still more preferably 1% or less. When the weight reduction rate is higher than 2%, the cyclization condensation reaction rate does not rise to a sufficiently high level even if the cyclization condensation reaction is performed simultaneously with the devolatilization step, and the physical properties of the resulting lactone ring-containing polymer. May decrease. In addition, when performing said cyclization condensation reaction, in addition to a polymer (g), you may coexist other thermoplastic resins.

  The hydroxyl group and ester group present in the molecular chain of the polymer (g) obtained in the polymerization step were subjected to a cyclization condensation reaction in advance to increase the cyclization condensation reaction rate to some extent, and then the devolatilization step was simultaneously used in combination. In the case of a form in which a cyclization condensation reaction is performed, a polymer obtained by a cyclization condensation reaction performed in advance (a polymer in which at least a part of a hydroxyl group and an ester group present in a molecular chain are subjected to a cyclization condensation reaction) and a solvent, The devolatilization step may be used as it is, and may be introduced into the cyclization condensation reaction. If necessary, the polymer (at least a part of the hydroxyl group and ester group present in the molecular chain is subjected to cyclization condensation reaction). You may introduce | transduce into the cyclocondensation reaction which used the devolatilization process together after passing through other processes, such as adding a solvent again after isolating a compound.

  The devolatilization step is not limited to being completed at the same time as the cyclization condensation reaction, and may be completed after a lapse of time from the completion of the cyclization condensation reaction.

  When the acrylic resin has a ring structure such as a lactone ring in the main chain, a cyclization catalyst may be used. However, a small amount of unreacted reactive group is present even after the catalyst is added and the cyclization condensation reaction is sufficiently performed. It is preferable to add a deactivator for the cyclization condensation catalyst because problems such as foaming and thickening due to cross-linking between polymers may occur during molding. In many cases, an acid catalyst or a basic catalyst is used in the cyclization condensation reaction. In this case, the deactivator deactivates the catalyst by a neutralization reaction. May be a basic substance. Conversely, when the catalyst is a basic substance, an acidic substance may be used as the deactivator. The deactivator is not particularly limited as long as it does not generate a substance that inhibits the physical properties of the resin composition during heat processing, but when a basic substance is used as the deactivator, for example, a metal carboxylate , Metal complexes, metal oxides, and the like, metal carboxylates and metal oxides are preferable, and metal carboxylates are particularly preferable. Here, the metal is not particularly limited as long as it does not inhibit the physical properties of the resin composition and does not cause environmental pollution at the time of disposal. For example, alkali metals such as lithium, sodium, and potassium; magnesium Alkaline earth metals such as calcium, strontium and barium; zinc; zirconium; and the like. The carboxylic acid constituting the metal carboxylate is not particularly limited. For example, formic acid, acetic acid, propionic acid, butyric acid, valeric acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, Lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid, tridecanoic acid, pentadecanoic acid, heptadecanoic acid, lactic acid, malic acid, citric acid, oxalic acid, malonic acid, succinic acid, fumaric acid, maleic acid, adipic acid, etc. Is mentioned. The organic component in the metal complex is not particularly limited, and examples thereof include acetylacetone. Examples of the metal oxide include zinc oxide, calcium oxide, magnesium oxide and the like, and zinc oxide is preferable. On the other hand, when an acidic substance is used for the deactivator, for example, an organic phosphoric acid compound or a carboxylic acid can be used. A quencher may be used independently or may use 2 or more types together. The quenching agent may be added in any form such as a solid, powder, dispersion, suspension, aqueous solution, etc., and is not particularly limited.

  The blending amount of the deactivator may be appropriately adjusted according to the catalyst used for the cyclization condensation, and is not particularly limited, but is preferably 10 to 10,000 ppm, more preferably based on the acrylic resin. Is 50 to 5,000 ppm, more preferably 100 to 3,000 ppm. If the amount of the deactivator is less than 10 ppm, the action of the deactivator is insufficient, and foaming or thickening due to cross-linking between polymers may occur during molding. On the contrary, when the compounding amount of the deactivator exceeds 10,000, the deactivator is used more than necessary, and the physical properties of the resin composition may be inhibited such as a decrease in molecular weight.

  The timing of adding the deactivator is, in particular, as long as it is after the catalyst is added and the cyclization condensation reaction is sufficiently performed in the production of the acrylic resin, and before the obtained resin composition is thermally processed. It is not limited. For example, a deactivator is added at a predetermined stage during the production of an acrylic resin, or after producing an acrylic resin, the acrylic resin, the deactivator, other components, etc. are simultaneously heated and melted and kneaded. A method of heating and melting an acrylic resin and other components, adding a deactivator thereto and kneading the mixture; an acrylic resin being heated and melted, and a deactivator and other components there And the like. In this case, it is preferable to provide a devolatilization step after kneading the thermoplastic resin and the quenching agent. This is because the obtained thermoplastic resin hardly causes a foaming phenomenon during heat processing. Examples of the devolatilization step include the devolatilization step described above as the devolatilization step performed in the production of the lactone ring-containing polymer.

  The lactone ring-containing polymer preferably has a weight loss rate of 150 to 300 ° C. in dynamic TG measurement of 1% by weight or less, more preferably 0.5% by weight or more, and still more preferably 0.3% by weight. % Or less.

  Since the lactone ring-containing polymer has a high cyclization condensation reaction rate, it is possible to avoid the disadvantage that bubbles and silver streaks enter the molded product after molding. Furthermore, since the lactone ring structure is sufficiently introduced into the polymer due to a high cyclization condensation reaction rate, the obtained lactone ring-containing polymer has sufficiently high heat resistance.

  The acrylic resin according to the present invention has high heat resistance even if it is a copolymer of an N-substituted maleimide and an acrylic monomer, and is effective, but in terms of transparency, mechanical properties, etc. A lactone ring-containing polymer is more preferred.

  In addition, the acrylic resin may have an ultraviolet absorbing ability as long as the heat resistance, physical properties, and optical properties are not impaired.

[Ultraviolet absorbing resin]
The ultraviolet absorbing resin according to the present invention has a polymer structural unit (repeating structural unit) constructed by polymerizing an ultraviolet absorbing monomer. Any UV-absorbing monomer can be used as long as it exhibits UV-absorbing properties, but those having a polymerizable group introduced into a benzotriazole derivative, benzophenone derivative, or triazine derivative are preferred. The UV-absorbing resin preferably has a light transmittance of 380 nm at a thickness of 50 μm of 10% or less, more preferably 5% or less, and most preferably 1% or less.

  Specific examples of the ultraviolet absorbing monomer include 2- [2′-hydroxy-5′-methacryloyloxy] ethylphenyl] -2H-benzotriazole, 2- [2′-hydroxy-5′-methacryloyloxy]. Benzotriazole-based ultraviolet absorbing monomers such as [phenyl] -2H-benzotriazole, 2- [2′-hydroxy-3′-t-butyl-5′-methacryloyloxy] phenyl] -2H-benzotriazole; -Diphenyl-6- [2-hydroxy-4- (2-acryloyloxyethoxy)]-s-triazine, 2,4-bis (2-methylphenyl) -6- [2-hydroxy-4- (2-acryloyl) Oxyethoxy)]-s-triazine, 2,4-bis (2-methoxyphenyl) -6- [2-hydroxy-4- (2-actyl) Royloxyethoxy)]-s-triazine, 2,4-bis (2-ethylphenyl) -6- [2-hydroxy-4- (2-acryloyloxyethoxy)]-s-triazine, 2,4-bis ( 2-Ethoxyphenyl) -6- [2-hydroxy-4- (2-acryloyloxyethoxy)]-s-triazine, 2,4-diphenyl-6- [2-hydroxy-4- (2-methacryloyloxyethoxy) ] -S-triazine, 2,4-bis (2-methylphenyl) -6- [2-hydroxy-4- (2-methacryloyloxyethoxy)]-s-triazine, 2,4-bis (2-methoxyphenyl) ) -6- [2-hydroxy-4- (2-methacryloyloxyethoxy)]-s-triazine, 2,4-bis (2-ethylphenyl) -6- [2-hydride Roxy-4- (2-methacryloyloxyethoxy)]-s-triazine, 2,4-bis (2-ethoxyphenyl) -6- [2-hydroxy-4- (2-methacryloyloxyethoxy)]-s-triazine 2,4-bis (2,4-dimethoxyphenyl) -6- [2-hydroxy-4- (2-acryloyloxyethoxy)]-s-triazine, 2,4-bis (2,4-dimethylphenyl) -6- [2-hydroxy-4- (2-acryloyloxyethoxy) -s-triazine, 2,4-bis (2,4-diethoxyphenyl) -6- [2-hydroxy-4- (2-acryloyl) Oxyethoxy)]-s-triazine, 2,4-bis (2,4-diethylphenyl) -6- [2-hydroxy-4- (2-acryloyloxyethoxy)]-s- Riazine, 2- [2-hydroxy-4- (11-acryloyloxy-undecyloxy) phenyl] -4,6-diphenyl-1,3,5-triazine, 2- [2-hydroxy-4- (11- Methacryloyloxy-undecyloxy) phenyl] 4,6-diphenyl-1,3,5-triazine, 2- [2-hydroxy-4- (2-methacryloyloxyethoxy) phenyl] -4,6-diphenyl-1, 3,5-triazine, 2- [2-hydroxy-4- (11-acryloyloxy-undecyloxy) phenyl] 4,6-bis (2,4-dimethylphenyl) 1,3,5-triazine, 2, 4-Bis (2,4-dimethylphenyl) -6- [2-hydroxy-4- (11-methacryloyloxyundecyloxy) phenyl] -1,3,5 Triazine, 2,4-bis (2,4-dimethylphenyl) -6 may be mentioned [2-hydroxy-4- (2-methacryloyloxy) phenyl] -1,3,5-triazine.

  These ultraviolet absorbing monomers may be used alone or in combination of two or more.

  As for the content rate of the ultraviolet absorptive monomer unit contained in the ultraviolet absorptive resin concerning this invention, it is preferable that a minimum is 20 mass% and an upper limit is 90 mass%. If it is less than 20% by mass, the UV blocking ability may not be sufficiently exhibited, and if it exceeds 90% by mass, the acrylic resin composition may be yellowed. A more preferable lower limit is 30% by mass, and an upper limit is 80% by mass.

  The ultraviolet-absorbing resin according to the present invention is obtained by copolymerizing an ultraviolet-absorbing monomer alone or a monomer other than the ultraviolet-absorbing monomer and the ultraviolet-absorbing monomer. A known monomer can be used as the monomer other than the UV-absorbing monomer, but from the viewpoint of compatibility with the acrylic resin, acrylic acid, methacrylic acid and derivatives thereof, and cyanide are used. Vinyl monomers and aromatic vinyl monomers are preferred. When using acrylic acid, methacrylic acid and its derivatives as monomers other than UV-absorbing monomers, UV-absorbing resins containing UV-absorbing monomers and methyl methacrylate in terms of excellent optical properties and thermal stability Is most preferred. Or, when a vinyl cyanide monomer and an aromatic vinyl monomer are used as monomers other than the UV-absorbing monomer, the UV absorption includes a UV-absorbing monomer, a monomer containing acrylonitrile and styrene. Is preferred. In addition, since an ultraviolet absorbing resin containing an ultraviolet absorbing monomer may have insufficient heat resistance and thermal stability, it may have a ring structure in the main chain. In order to introduce a ring structure, N-substituted maleimides such as phenylmaleimide, cyclohexylmaleimide, and methylmaleimide may be copolymerized, or in a molecular chain (also referred to as a polymer main skeleton or main chain). ) May be introduced with a lactone ring structure, a glutaric anhydride structure, a glutarimide structure, or a maleimide structure.

[Thermoplastic resin composition]
The content of the acrylic resin in the thermoplastic resin composition according to the present invention is not particularly limited as long as it satisfies the requirements of heat resistance and light transmittance, but is preferably 50% by weight or more, and 60% by weight or more. Further preferred. 70% by weight or more is particularly preferable. If it is less than 50% by weight, the expected heat resistance may not be exhibited, and the resin composition tends to be inferior in mechanical strength and transparency.

  The content of the ultraviolet absorbing resin in the thermoplastic resin composition according to the present invention is not particularly limited as long as it satisfies the requirements of heat resistance and light transmittance, but the lower limit is preferably 1% by weight or more. More preferred is wt% or more. The upper limit is preferably 50% by weight or less, more preferably 40% by weight or less, and further preferably 30% by weight or less. If it exceeds 50% by weight, there is a risk of problems in terms of mechanical strength and yellowing.

  The refractive index of the acrylic resin in the thermoplastic resin composition according to the present invention is preferably such that the difference (absolute value) from the refractive index of the ultraviolet absorbing resin is 0.030 or less, more preferably 0.025. Hereinafter, it is more preferably 0.020 or less. When the difference in refractive index exceeds 0.030, the transparency of the resin composition obtained when the acrylic resin and the ultraviolet absorbing resin are not thermodynamically compatible may be impaired.

  The glass transition temperature (Tg) of the thermoplastic resin composition according to the present invention is preferably 110 ° C. or higher, more preferably 115 ° C. or higher, still more preferably 120 ° C. or higher, still more preferably 125 ° C. or higher, and most preferably 130. It is above ℃. Here, the glass transition temperature is as described above.

  In the thermoplastic resin composition according to the present invention, the acrylic resin and the UV-absorbing resin are thermodynamically compatible with each other, so that a resin composition with excellent transparency and molding processability can be obtained. This is preferable. The thermodynamic compatibility of the acrylic resin and the ultraviolet absorbing resin can be confirmed by measuring the glass transition point of a thermoplastic resin composition obtained by mixing them. Specifically, it can be said that the glass transition point measured by DSC is thermodynamically compatible by observing only one point in the mixture of the acrylic resin and the ultraviolet absorbing resin.

  Further, the thermoplastic resin composition according to the present invention may contain other resin components. Examples of other resin components include olefin polymers such as polyethylene, polypropylene, ethylene-propylene copolymer, and poly (4-methyl-1-pentene); halogen-containing polymers such as vinyl chloride and chlorinated vinyl resins; Acrylic polymers such as polymethyl methacrylate; styrene polymers such as polystyrene, styrene-methyl methacrylate copolymer, styrene-acrylonitrile copolymer, acrylonitrile-butadiene-styrene block copolymer; polyethylene terephthalate, polybutylene terephthalate, Polyesters such as polyethylene naphthalate; polyamides such as nylon 6, nylon 66, nylon 610; polyacetal: polycarbonate; polyphenylene oxide; polyphenylene sulfide: polyether Polyether ketone; polysulfone; polyether sulfone: polyoxyethylene Penji alkylene; polyamideimide; polybutadiene rubber, rubber-like polymer such as acrylic rubber ABS resin or ASA resin blended with; and the like. The rubbery polymer preferably has a graft portion having a composition compatible with the lactone ring polymer of the present invention on the surface, and the average particle size of the rubbery polymer is transparent when formed into an extruded film. From the viewpoint of improving the properties, the thickness is preferably 100 nm or less, and more preferably 70 nm or less.

  The thermoplastic resin composition according to the present invention may contain other additives. Other additives include, for example, hindered phenol-based, phosphorus-based, sulfur-based antioxidants; light stabilizers, weather stabilizers, heat stabilizers, and other stabilizers: reinforcing materials such as glass fibers and carbon fibers. : Near-infrared absorbers; flame retardants such as tris (dibromopropyl) phosphate, triallyl phosphate, antimony oxide; antistatic agents such as anionic, cationic and nonionic surfactants; inorganic pigments, organic pigments, dyes, etc. Organic fillers and inorganic fillers: resin modifiers; organic fillers and inorganic fillers; plasticizers; lubricants; antistatic agents; flame retardants;

  The content of other additives in the amorphous thermoplastic resin molded body is preferably 0 to 5% by weight, more preferably 0 to 2% by weight, and still more preferably 0 to 0.5% by weight.

[Use and molding of thermoplastic resin composition]
The thermoplastic resin composition of the present invention is not only excellent in transparency and heat resistance, but also has properties such as low colorability, mechanical strength and molding processability, and has an ultraviolet absorbing ability, so it is an extruded film or sheet. It is also useful. That is, a preferred embodiment of the thermoplastic resin composition of the present invention is an extruded film or sheet made of the thermoplastic resin composition.

  As an example of a preferred application, a method for producing an extruded film from the thermoplastic resin composition of the present invention will be described in detail below.

[Extruded film]
A method for producing an extruded film from the thermoplastic resin composition of the present invention is not particularly limited. For example, a thermoplastic resin composition having a glass transition temperature of 110 ° C. or higher, other thermoplastic resins and other additives, and the like. Then, it can be mixed by a conventionally known mixing method to produce an extruded film. As a method for producing this acrylic resin composition, for example, a method of pre-blending with a mixer such as an omni mixer and then extruding and kneading the obtained mixture can be employed. In this case, the kneader used for extrusion kneading is not particularly limited. For example, a conventionally known kneader such as an extruder such as a single screw extruder or a twin screw extruder or a pressure kneader is used. Can do.

  Examples of the melt extrusion method include a T-die method and an inflation method, and the molding temperature of the extruded film at that time is preferably 150 to 350 ° C., more preferably 200 to 300 ° C.

  When the extruded film is formed by the T-die method, a T-die is attached to the tip of a known single-screw extruder or biaxial extruder, and a film in the form of a take-up roll can be obtained from the extruded film. . At this time, it is possible to adjust the temperature of the winding roll as appropriate and apply stretching in the extruding direction so that a uniaxial stretching process can be performed. Moreover, it is also possible to add processes, such as sequential biaxial stretching and simultaneous biaxial stretching, by adding the process of extending | stretching a film in the direction perpendicular | vertical to an extrusion direction.

  The extruded film of the present invention may be an unstretched film or a court stretch film. When stretching, a uniaxially stretched film or a biaxially stretched film may be used. In the case of a biaxially stretched film, it may be a film that has been simultaneously biaxially stretched or a film that has been successively biaxially stretched. In the case of biaxial stretching, the mechanical strength is improved and the film performance is improved. The optical film of the present invention can suppress an increase in retardation even when stretched by mixing other amorphous thermoplastic resin, and can maintain optical isotropy.

  The stretching temperature is preferably near the glass transition temperature of the extruded film raw material thermoplastic resin composition, specifically, (glass transition temperature-30) ° C. to (glass transition temperature + 100) ° C. Preferably, it is (glass transition temperature−20) ° C. to (glass transition temperature + 80) ° C. When it is lower than (glass transition temperature-30) ° C., a sufficient draw ratio cannot be obtained, which is not preferable. When the temperature is higher than (glass transition humidity + 100) ° C., resin flow occurs and stable stretching cannot be performed.

  The court stretch ratio defined by the area ratio is preferably in the range of 1.1 to 25 times, more preferably in the range of 1.3 to 10 times. When it is less than 1.1 times, it is not preferable because it does not lead to improvement of toughness accompanying stretching. If it is larger than 25 times, the effect of increasing the draw ratio is not recognized.

  The stretching speed (one direction) is preferably in the range of 10 to 20000% / min, more preferably in the range of 100 to 10000% / min. If it is slower than 10% / min, it takes time to obtain a sufficient draw ratio, and the production cost is increased, which is not preferable. If it is faster than 20000% / min, the stretched extruded film may be broken, which is not preferable.

  In order to stabilize the optical isotropy and mechanical properties of the extruded film, heat treatment (annealing) or the like can be performed after the stretching treatment.

  Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples, but the present invention is not limited to these. Hereinafter, for convenience, “part by weight” may be simply referred to as “part”, and “liter” may be simply referred to as “L”.

<Weight average molecular weight>
The weight average molecular weight of the polymer was determined by polystyrene conversion of GPC (GPC system manufactured by Tosoh Corporation). Chloroform was used as the developing solution.

<Thermal analysis of resin>
The thermal analysis of the resin was performed using DSC (manufactured by Rigaku Corporation, apparatus name: DSC-8230) under conditions of about 10 mg of sample, a heating rate of 10 ° C./min, and a nitrogen flow of 50 cc / min. The glass transition temperature (Tg) was determined by the midpoint method according to ASTM-D-3418.

<Measurement of volatile content in resin>
The amount of residual volatile components contained in the resin was measured using gas chromatography (manufactured by Shimadzu Corporation, apparatus name: GC14A).

<Coloring degree of resin (YI)>
The degree of coloration (YI) of the resin is obtained by dissolving the resin in chloroform and placing it in a quartz cell as 15% by weight. According to JIS-K-7103, a color difference meter (manufactured by Nippon Denshoku Industries Co., Ltd., apparatus name: SZ-Σ90) is used. And measured with transmitted light.

<Light transmittance>
A film having a thickness of 50 μm was prepared by melt extrusion molding, and light transmittances of 380 nm and 500 nm were measured using a spectrophotometer (manufactured by Shimadzu Corporation, apparatus name: UV-3100).

<Content of lactone ring structural unit>
First, based on the weight loss that occurs when all the hydroxyl groups are dealcoholated as methanol from the polymer composition obtained by polymerization, before the decomposition of the polymer starts from 150 ° C. before the weight reduction starts in dynamic TG measurement. From the weight loss due to the dealcoholization reaction up to 300 ° C., the dealcoholization reaction rate was determined.

That is, in the dynamic TG measurement of the polymer having a lactone ring structure, the weight reduction rate between 150 ° C. and 300 ° C. is measured, and the obtained actual weight reduction rate is defined as (X). On the other hand, from the composition of the polymer, all the hydroxyl groups contained in the polymer composition are involved in the formation of the lactone ring, so that it becomes an alcohol and is dealcoholized. (Y) is the weight loss rate calculated on the assumption that the% dealcoholization reaction has occurred. The theoretical weight reduction rate (Y) is more specifically the molar ratio of raw material monomers having a structure (hydroxyl group) involved in the dealcoholization reaction in the polymer, that is, the raw material unit in the polymer composition. It can be calculated from the content of the monomer. These values (X, Y) are calculated from the dealcoholization formula:
1- (actual weight reduction rate (X) / theoretical weight reduction rate (Y))
Substituting into, the value is obtained and expressed in% to obtain the dealcoholization reaction rate.

  As an example, the proportion of the lactone ring structure in the pellet obtained in Synthesis Example 1 described later is calculated. When the theoretical weight loss rate (Y) of this polymer was determined, the molecular weight of methanol was 32, the molecular weight of methyl 2- (hydroxymethyl) acrylate was 116, and methyl 2- (hydroxymethyl) acrylate. Since the content (weight ratio) in the polymer is 20% by weight in terms of composition, (32/116) × 20≈5.52% by weight. On the other hand, the actual weight loss rate (X) by dynamic TG measurement was 0.18% by weight. When these values are applied to the above-described dealcoholization calculation formula, 1− (0.18 / 5.52) ≈0.967, and the dealcoholization reaction rate is 96.7%.

  And the content rate (weight ratio) in the said copolymerization composition of the raw material monomer which has the structure (hydroxy group) which participates in lactone cyclization as what the predetermined | prescribed lactone cyclization was performed by this dealcoholization reaction rate ) Is multiplied by the dealcoholization reaction rate and converted to the content (weight ratio) of the structure of the lactone ring unit, the content of the lactone ring structure in the copolymer can be calculated. In the case of Synthesis Example 1, the content of 2- (hydroxymethyl) methyl acrylate in the copolymer is 20.0 wt%, the calculated dealcoholization reaction rate is 96.7 wt%, and the molecular weight is 116 Since the formula amount of the lactone cyclized structural unit produced when methyl hydroxymethyl) is condensed with methyl methacrylate is 170, the content of the lactone ring in the copolymer is 28.3 (20. 0 × 0.967 × 170/116) wt%.

[Synthesis Example 1]
In a 30 L reaction kettle equipped with a stirrer, temperature sensor, condenser, and nitrogen inlet, 40 parts methyl methacrylate (MMA), 10 parts methyl 2- (hydroxymethyl) methyl acrylate (MHMA), 50 parts toluene The mixture was heated up to 105 ° C. while refluxing nitrogen and refluxed, and 0.05 part of t-amylperoxyisononanoate (manufactured by Arkema Yoshitomi Co., Ltd., trade name: Lupazole 570) was used as an initiator. At the same time, while 0.10 parts of t-amylperoxyisononanoate was added dropwise over 2 hours, solution polymerization was performed under reflux (about 105 to 110 ° C.), followed by further aging for 4 hours. It was.

  To the obtained polymer solution, 0.05 part of 2-ethylhexyl phosphate (manufactured by Sakai Chemical Industry Co., Ltd., trade name: Phoslex A-8) was added and refluxed (about 90 to 110 ° C.) for 5 hours. A cyclization condensation reaction was performed. Subsequently, the polymer solution obtained by the cyclization condensation reaction was subjected to a vent 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 It is introduced into a 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 amount, and cyclization condensation reaction and devolatilization are carried out in the extruder. By extrusion, transparent lactone ring-containing acrylic resin pellets (1A) were obtained. The obtained pellets had a glass transition temperature of 130 ° C.

[Synthesis Example 2]
The ultraviolet absorbing resin having the composition shown in Table 1 was polymerized by the same solution polymerization as in Synthesis Example 1, and devolatilized by a vent-type screw twin screw extruder in the same manner as in Synthesis Example 1 to obtain ultraviolet absorbing resin pellets (1B To 5B). Their physical properties are summarized in Table 1.

[Examples 1 to 5]
The pellets obtained in Synthesis Examples 1 and 2 were 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 with the composition shown in Table 2, and an extruded film having a thickness of 50 μm. It was created.
Table 2 shows the glass transition temperature of the obtained extruded film and the light transmittance at 500 nm and 380 nm.

[Comparative Example 1]
Similarly to the example, 2- (5-methyl-2-hydroxyphenyl) benzotriazole (manufactured by Ciba Specialty Chemicals Co., Ltd., trade name: Tinuvin P) was blended with the composition of Table 2, and the same as in Example 1 An extruded film was produced under the conditions.
Table 2 shows the glass transition temperature of the obtained extruded film and the light transmittance at 500 nm and 380 nm.

[Synthesis Example 3]
In a 30 L reaction kettle equipped with a stirrer, temperature sensor, cooling pipe, nitrogen introduction pipe, 42 parts of methyl methacrylate (MMA), 6 parts of methyl 2- (hydroxymethyl) acrylate (MHMA), 2 parts of 3 -(2H-1,2,3-benzotriazol-2-yl) -4-hydroxyphenethyl methacrylate (manufactured by Otsuka Chemical Co., Ltd., trade name: RUVA-93), 50 parts of toluene, 0.025 parts Adekastab 2112 (manufactured by Asahi Denka Kogyo Co., Ltd.) and 0.025 part of n-dodecyl mercaptan were charged, and the temperature was raised to 105 ° C. while refluxing nitrogen. When refluxed, 0.05 part of t-amyl was used as an initiator. While adding peroxyisononanoate (Arkema Yoshitomi Co., Ltd., trade name: Lupazole 570), 0.10 parts of t-amylperoxyisonononoe Dropwise over bets 3 hours, subjected to solution polymerization under reflux (about devices 105 through 110 ° C.), the mixture was aged over an additional 4 hours.

  0.05 parts of stearyl phosphate (manufactured by Sakai Chemical Industry Co., Ltd., trade name: Phoslex A-18) was added to the obtained polymer solution, and the mixture was refluxed (about 90 to 110 ° C.) for 2 hours. A polycondensation reaction was performed. Subsequently, heat treatment was performed at 240 ° C. for 30 minutes by an autoclave to complete the cyclization condensation reaction.

  Subsequently, the polymer solution obtained by the cyclization condensation reaction was prepared by adding 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 (upstream). From the side, referred to as the first, second, third and fourth vents) vent type screw twin screw extruder (φ = 29.75 mm, L / D = 30) It was introduced at a treatment rate and devolatilized. At that time, the separately prepared antioxidant / deactivator mixed solution was injected after the first vent at a charging rate of 0.02 kg / hour using a high-pressure pump. Further, after the third vent, ion exchange water was injected at a charging rate of 0.01 kg / hour using a high pressure pump.

  Antioxidant / deactivator mixed solution is 40 parts of Sumilizer GS (manufactured by Sumitomo Chemical Co., Ltd.), 17.5 parts of zinc octylate (3.6% of Nikka octix zinc, manufactured by Nippon Chemical Industry Co., Ltd.) as toluene. What was dissolved in 200 parts was used.

  A transparent lactone ring-containing heat-resistant acrylic resin pellet (2A) was obtained by the devolatilization operation. The obtained pellet had a glass transition temperature of 128 ° C. Further, an extruded film having a thickness of 50 μm was produced from the obtained pellets under the same conditions as in Example 1. The light transmittance at 380 nm of the obtained film was 20.6%.

[Synthesis Example 4]
In a 30 L reaction kettle equipped with a stirrer, temperature sensor, cooling pipe, and nitrogen introduction pipe, 42.5 parts of methyl methacrylate, 5 parts of N-phenylmaleimide, 2.5 parts of styrene, 50 parts of toluene, acetic anhydride as an organic acid 0.2 part, 0.06 part of n-dodecyl mercaptan was charged as a chain transfer agent, and nitrogen gas was bubbled for 10 minutes while stirring, and then the temperature was raised under a nitrogen atmosphere. When the temperature in the reaction kettle reached 100 ° C., 0.075 part of t-butylperoxyisopropyl carbonate was added into the reaction kettle, and at the same time, 2 parts of styrene and t-butyl bubbled with nitrogen gas in a dropping tank. A mixed solution of 0.075 part of butyl peroxyisopropyl carbonate was added at a constant rate over 5 hours. The polymerization reaction was carried out at a polymerization temperature of 105 to 110 ° C. for 15 hours under reflux. Thereafter, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (manufactured by Sanko Co., Ltd., trade name: HCA) is 0 as a phosphorus-based antioxidant. 0.1% by weight, pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate (Asahi Denka Kogyo Co., Ltd., trade name: AO-) as a phenolic antioxidant 60) was added and mixed at 0.02% by weight. Subsequently, the obtained polymerization liquid 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, a fore vent number of 4 (first and second from the upstream side). , Referred to as “3rd, 4th vent”), is supplied to a vent type screw twin screw extruder (φ = 29.75 mm, L / D = 30), vacuum devolatilized from the vent port, and the extruded strand is pelletized Thus, heat-resistant acrylic resin pellets (3A) were obtained. The obtained pellet had a glass transition temperature of 132 ° C.

[Synthesis Example 5]
In a 30 L reaction kettle equipped with a stirrer, a temperature sensor, a cooling pipe, and a nitrogen introduction pipe, 32.5 parts of styrene (ST), 10.0 parts of acrylonitrile (AN), 7.5 parts of UVA-1, 50 Part of toluene, 0.025 part Adeka Stub 2112 (Asahi Denka Kogyo Co., Ltd.) was charged, and the temperature was raised to 110 ° C. while passing through nitrogen, and when refluxed, 0.03 part t-amyl was used as an initiator. While adding peroxyisononanoate (Arkema Yoshitomi Corp., trade name: Lupazole 570), 0.10 parts of t-amyl peroxyisononanoate was added dropwise over 5 hours while refluxing (about Solution polymerization at 115 to 100 ° C., followed by further aging for 4 hours.

  Next, the obtained polymer 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, a fore vent number of 4 (first and 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, after the first, second, and third vents, ion exchange water was injected at a charging rate of 0.01 kg / hour using a high-pressure pump, respectively.

  By the above devolatilization operation, a transparent ultraviolet absorbing resin pellet (6B) was obtained. A film was formed from the obtained pellets under the same conditions as in Example 1, but the light transmittance at 380 nm at a thickness of 50 μm was 1% or less.

[Synthesis Example 6]
Synthesis Example 4 except that the monomer composition charged was 28.1 parts styrene (ST), 9.4 parts acrylonitrile (AN), 5 parts phenylmaleimide (PMI), and 7.5 parts UVA-1. In the same manner as above, a transparent ultraviolet absorbing resin pellet (7B) was obtained. A film was formed from the pellets obtained, and the light transmittance at 380 nm at a thickness of 50 μm was 1% or less.

[Synthesis Example 7]
Transparent UV-absorbing resin in the same manner as in Synthesis Example 4 except that the monomer composition was 32 parts styrene (ST), 10.5 parts acrylonitrile (AN), and 7.5 parts UVA-2. Pellets (8B) were obtained. A film was formed from the pellets obtained, and the light transmittance at 380 nm at a thickness of 50 μm was 1% or less.

  Table 3 summarizes the compositions and light transmittances of the ultraviolet absorbing resins 6B to 8B.

[Examples 6 to 9]
Heat-resistant acrylic resins (2A, 3A) obtained in Synthesis Examples 3 and 4 and obtained in Synthesis Examples 5 to 7

UV-absorbing resins (6B, 7B, 8B) were blended as shown in Table 4 and melt kneaded using a twin screw extruder having a 20 mmφ screw, melt extruded from a coat hanger type T die having a width of 150 mm, thickness A 50 μm extruded film was prepared.

  Table 4 shows the glass transition temperature of the obtained extruded film and the light transmittance at 500 nm and 380 nm.

  The thermoplastic resin composition and the extruded film or sheet according to the present invention are suitably used as an optical material.

Claims (4)

At least (A) an acrylic resin;
(B) a composition comprising an ultraviolet absorbing resin having a light transmittance of 380 nm at a thickness of 50 μm and a wavelength of 10% or less, wherein the composition has (a) a glass transition temperature of 110 ° C. or higher,
(B) The light transmittance at a wavelength of 500 nm at a thickness of 50 μm is 80% or more,
The light transmittance at a wavelength of 380 nm is 30% or less,
Thermoplastic resin composition characterized in that The thermoplastic resin composition according to claim 1, wherein (A) the acrylic resin according to claim 1 has a ring structure in the main chain. The thermoplastic resin composition according to claim 1, wherein the acrylic resin (A) according to claim 1 or 2 has a lactone ring structure. An extruded film or sheet comprising the thermoplastic resin composition according to any one of claims 1 to 3.