JP2021126877A - Method for producing molded product - Google Patents

Abstract

To provide a method for producing a molded product, which can more easily produce a molded product containing a polycarbonate resin and a (meth) acrylic resin, and is excellent in transparency in a larger area.SOLUTION: There is provided a method for producing a molded product, which comprises a step of injection molding a resin composition under the condition of a formula (1), in which the resin composition contains (meth)acrylic resin and polycarbonate resin, a content of the (meth)acrylic resin is 5 to 40 pts.mass based on the total content of 100 pts.mass of the (meth)acrylic resin and the polycarbonate resin, and a content of the polycarbonate resin is 60 to 95 pts.mass. Formula (1): Tgresin-15≤Tmold≤Tgresin+30. (In the formula, Tgresin is a glass transition temperature (°C) of the resin composition, and Tmold is a temperature of a mold in contact with the injected resin composition.)SELECTED DRAWING: None

Description

The present invention relates to a method for producing a molded product of a resin composition containing a (meth) acrylic resin and a polycarbonate resin.

Methacrylic resins are generally known to be excellent in transparency, surface hardness, ultraviolet resistance, weather resistance, chemical properties, etc., but are insufficient in dimensional stability, impact resistance, low temperature resistance, and the like. On the other hand, aromatic polycarbonate resins are generally excellent in high temperature stability, dimensional stability, impact resistance, rigidity, transparency, etc., but are insufficient in scratch resistance and long-term ultraviolet resistance, and stress birefringence occurs. It's easy to do.

In view of the above-mentioned characteristics of both resins, it is expected that the resin composition containing the methacrylic resin and the aromatic polycarbonate resin can be used for various purposes by compensating for the defects of one component of the other component. .. However, since the methacrylic resin and the aromatic polycarbonate resin are mutually incompatible resins, when both are mixed, the obtained resin composition generally becomes opaque and cannot be used in applications requiring transparency.

Further, a resin composition containing an aromatic polycarbonate resin and a methacrylic resin usually has a property of becoming cloudy when heated above a certain temperature (Lower Critical Solution Temperature), and is abbreviated as "LCST behavior". ”). Therefore, the clouding temperature (that is, the clouding point) exceeds the upper limit of the temperature range usually set in the molding method for molding the resin composition such as the injection molding method, the press molding method, and the melt extrusion molding method. If there is, when the resin composition is molded by the above molding method, the obtained molded product may become cloudy and opaque.

Therefore, various techniques have been developed in order to obtain a transparent resin composition containing a methacrylic resin and an aromatic polycarbonate resin. As such a technique, for example, adjusting the molecular weight and child monomer of the methacrylic resin, improving the molding conditions, and the like are known.

For example, Patent Document 1 discloses an aromatic (meth) acrylate unit (a1) of 5 to 80% by mass and a methyl methacrylate unit (a2) 20 in order to efficiently and inexpensively produce a molded product having excellent surface hardness and transparency. A surface hardness improver containing a polymer containing ~ 95% by mass and having a mass average molecular weight of 5,000 to 30,000, the surface hardness improving agent thereof is 5 to 60% by mass, and the polycarbonate resin is 40 to 95% by mass. Discloses a thermoplastic resin composition containing%, and a molded product obtained by molding the thermoplastic resin composition (see Patent Document 1, Claims 1 to 3, [0007], etc.). Further, Patent Document 1 discloses that an injection molding was used as a molding method to obtain a molded product at an injection temperature of 280 ° C. and a mold temperature of 90 ° C. (see Patent Document 1 [0047]).

Japanese Unexamined Patent Publication No. 2014-111799

However, when the manufacturing method described in Patent Document 1 is used, a molded product having transparency and a certain area can be obtained, but the molded product also has an opaque portion, and the production efficiency is not sufficient. rice field. Therefore, it was not easy to obtain a molded product having a larger area.

The present invention provides a method for producing a molded article having a wider area and excellent transparency, which can more easily produce a molded article containing a polycarbonate resin and a (meth) acrylic resin, and which is more efficient in producing the molded article. With the goal.

As a result of diligent studies, the present inventors have conducted injection molding of a resin composition containing a (meth) acrylic resin and a polycarbonate resin under specific conditions to obtain a polycarbonate resin and (meth) which are excellent in transparency over a wider area. ) We have found that a molded product containing an acrylic resin can be produced more easily and more efficiently, and have completed the present invention.

（式中、
Ｒ^１は、水素原子またはメチル基を表す。
Ｒ^２は、炭化水素環構造を有する基を表す。）
３．式（Ｉ）のＲ^２が、シクロアルキル基で置換されたアルキル基、シクロアルキル基、アルキル基で置換されたシクロアルキル基、フェニル基で置換されたアルキル基、フェニル基、アルキル基で置換されたフェニル基、ナフチル基で置換されたアルキル基、ナフチル基、アルキル基で置換されたナフチル基、ジシクロペンタニル基またはジシクロペンテニル基を表す、上記２に記載の成形体の製造方法。
４．前記式（Ｉ）で表される（メタ）アクリル酸エステルが、メタクリル酸シクロヘキシル、メタクリル酸ベンジル、メタクリル酸フェニルまたはメタクリル酸ナフチルである、上記２に記載の成形体の製造方法。
５．前記（メタ）アクリル酸アルキルが、アクリル酸メチルである上記２〜４のいずれか一項に記載の成形体の製造方法。
６．前記ポリカーボネート樹脂が、芳香族ポリカーボネート樹脂である、上記１〜５のいずれか一に記載の成形体の製造方法。
７．前記射出成形する工程が、ヒートアンドクール成形である、上記１〜６のいずれか一に記載の成形体の製造方法。 That is, the present specification includes the following embodiments.
1. 1. Contains (meth) acrylic resin and polycarbonate resin,
A resin having a (meth) acrylic resin content of 5 to 40 parts by mass and a polycarbonate resin content of 60 to 95 parts by mass with respect to a total content of 100 parts by mass of the (meth) acrylic resin and the polycarbonate resin. The composition,
A method for producing a molded product, which comprises a step of injection molding under the condition of satisfying the following formula (1).

Tg ^resin -15 ≤ T ^mold ≤ Tg ^resin +30 (1)
(During the ceremony,
Tg ^resin represents the glass transition temperature (° C.) of the resin composition.
T ^mold represents the temperature (° C.) of the mold that comes into contact with the injected resin composition. )
2. The (meth) acrylic resin
Monomer unit derived from methyl methacrylate is 55% by mass or more.
The monomer unit based on the (meth) acrylic acid ester represented by the following formula (I) is 10 to 40% by mass.
Contains 0.1 to 35% by weight of monomeric units based on alkyl (meth) acrylate (excluding methyl methacrylate and the (meth) acrylic acid ester represented by formula (I)).
The method for producing a molded product according to 1 above.

(During the ceremony,
R ¹ represents a hydrogen atom or a methyl group.
R ² represents a group having a hydrocarbon ring structure. )
3. 3. ^{R 2 of} formula (I) is substituted with an alkyl group substituted with a cycloalkyl group, a cycloalkyl group, a cycloalkyl group substituted with an alkyl group, an alkyl group substituted with a phenyl group, a phenyl group, or an alkyl group. The method for producing a molded product according to 2 above, which represents a phenyl group, an alkyl group substituted with a naphthyl group, a naphthyl group, a naphthyl group substituted with an alkyl group, a dicyclopentanyl group or a dicyclopentenyl group.
4. The method for producing a molded product according to 2 above, wherein the (meth) acrylic acid ester represented by the formula (I) is cyclohexyl methacrylate, benzyl methacrylate, phenyl methacrylate or naphthyl methacrylate.
5. The method for producing a molded product according to any one of 2 to 4 above, wherein the alkyl (meth) acrylate is methyl acrylate.
6. The method for producing a molded product according to any one of 1 to 5 above, wherein the polycarbonate resin is an aromatic polycarbonate resin.
7. The method for producing a molded product according to any one of 1 to 6 above, wherein the injection molding step is heat and cool molding.

By using the production method of the embodiment of the present invention, a molded product containing a polycarbonate resin and a (meth) acrylic resin, which has a larger area and is excellent in transparency, can be produced more easily and more efficiently. Optimal optical characteristics such as heat resistance, impact resistance, chemical resistance, hygroscopicity, surface hardness, and birefringence characteristics are suitable in combination with polycarbonate resin while maintaining the original excellent transparency of (meth) acrylic resin. It is possible to manufacture an improved molded product.

FIG. 1 schematically shows a method for producing a molded product according to the first embodiment of the present invention. FIG. 2 (A) shows the molded product of Example 8, and FIG. 2 (B) shows the molded product of Comparative Example 1.

The method for producing a molded product according to the embodiment of the present invention is as follows.
Contains (meth) acrylic resin and polycarbonate resin,
Specific specification that the content of the (meth) acrylic resin is 5 to 40 parts by mass and the content of the polycarbonate resin is 60 to 95 parts by mass with respect to the total content of 100 parts by mass of the (meth) acrylic resin and the polycarbonate resin. Includes a step of injection molding the resin composition of the above under specific conditions.
First, the (meth) acrylic resin and the polycarbonate resin will be described.

[Polycarbonate resin]
As used herein, the "polycarbonate resin" is a polycarbonate resin containing a structural unit derived from a dihydroxy compound. The polycarbonate resin is obtained by reacting, for example, a dihydroxy compound such as divalent phenol or isosorbide with a carbonylating agent by an interfacial polycondensation method or a molten ester exchange method; a carbonate prepolymer is replaced with a solid phase ester. Examples thereof include those obtained by polymerizing by a method or the like; and those obtained by polymerizing a cyclic carbonate compound by a ring-opening polymerization method. The polycarbonate resin is preferably an aromatic polycarbonate resin.

Examples of the divalent phenol include hydroquinone, resorcinol, 4,4'-dihydroxydiphenyl, bis (4-hydroxyphenyl) methane, bis {(4-hydroxy-3,5-dimethyl) phenyl} methane, 1,1-. Bis (4-hydroxyphenyl) ethane, 1,1-bis (4-hydroxyphenyl) -1-phenyl ethane, 2,2-bis (4-hydroxyphenyl) propane (commonly known as bisphenol A), 2,2-bis { (4-Hydroxy-3-methyl) phenyl} propane, 2,2-bis {(4-hydroxy-3,5-dimethyl) phenyl} propane, 2,2-bis {(4-hydroxy-3,5-dibromo) ) Phenyl} propane, 2,2-bis {(3-isopropyl-4-hydroxy) phenyl} propane, 2,2-bis {(4-hydroxy-3-phenyl) phenyl} propane, 2,2-bis (4) -Hydroxyphenyl) butane, 2,2-bis (4-hydroxyphenyl) -3-methylbutane, 2,2-bis (4-hydroxyphenyl) -3,3-dimethylbutane, 2,4-bis (4-hydroxy) Phenyl) -2-methylbutane, 2,2-bis (4-hydroxyphenyl) pentane, 2,2-bis (4-hydroxyphenyl) -4-methylpentane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 1,1-bis (4-hydroxyphenyl) -4-isopropylcyclohexane, 1,1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane, 9,9-bis (4-hydroxyphenyl) fluorene , 9,9-Bis {(4-Hydroxy-3-methyl) phenyl} fluorene, α, α'-bis (4-hydroxyphenyl) -o-diisopropylbenzene, α, α'-bis (4-hydroxyphenyl) -M-diisopropylbenzene, α, α'-bis (4-hydroxyphenyl) -p-diisopropylbenzene, 1,3-bis (4-hydroxyphenyl) -5,7-dimethyladamantan, 4,4'-dihydroxydiphenyl Examples include sulfone, 4,4'-dihydroxydiphenylsulfoxide, 4,4'-dihydroxydiphenylsulfide, 4,4'-dihydroxydiphenylketone, 4,4'-dihydroxydiphenyl ether, and 4,4'-dihydroxydiphenyl ester. These may be used alone or in combination of two or more.

Among these divalent phenols, bisphenol A, 2,2-bis {(4-hydroxy-3-methyl) phenyl} propane, 2,2-bis (4-hydroxyphenyl) butane, 2,2-bis (4) -Hydroxyphenyl) -3-methylbutane, 2,2-bis (4-hydroxyphenyl) -3,3-dimethylbutane, 2,2-bis (4-hydroxyphenyl) -4-methylpentane, 1,1-bis (4-Hydroxyphenyl) -3,3,5-trimethylcyclohexane and α, α'-bis (4-hydroxyphenyl) -m-diisopropylbenzene are preferred. In particular, bisphenol A alone, bisphenol A and 1,1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane, 2,2-bis{(4-hydroxy-3-methyl) phenyl } It is preferable to use in combination with at least one selected from the group consisting of propane and α, α'-bis (4-hydroxyphenyl) -m-diisopropylbenzene.

Examples of the carbonylating agent include carbonyl halides (such as phosgene), carbonate esters (such as diphenyl carbonate), and haloformates (such as dihaloformates of divalent phenols). These may be used alone or in combination of two or more.

The polycarbonate resin preferably has a standard polystyrene-equivalent mass average molecular weight of 10,000 to 50,000 as measured by gel permeation chromatography (GPC). When producing such an aromatic polycarbonate resin, a molecular weight modifier, a catalyst, or the like can be used as needed.

Polycarbonate resin, 300 ° C., a melt volume flow rate measured by 1.2kg load (MVR) is preferably in the 2~280cm ^3/10 min is preferably 2~100cm ^3/10 min. A polycarbonate resin having an MVR in such a range has excellent fluidity and is easily melt-kneaded when mixed with a methacrylic resin. Further, when a polycarbonate resin having an MVR in such a range is used, the molded product of the present embodiment has excellent mechanical strength.

[(Meta) acrylic resin]
As used herein, the term "(meth) acrylic resin" includes acrylic resins and methacrylic resins.
The acrylic resin is a polymer containing a monomer unit derived from a monomer having an acrylic group, and the monomer unit derived from the monomer having an acrylic group has a weight of more than 50 mol% of all the monomer units. It is a coalescence.
The methacrylic resin is a polymer having a monomer unit derived from a monomer having a methacrylic group, and the monomer unit derived from the monomer having a methacrylic group is 50 mol% or more of all the monomer units. It is a polymer.

[acrylic resin]
Examples of the acrylic resin include homopolymers of acrylic monomers such as acrylic acid, acrylic acid ester, and acrylonitrile, copolymers of two or more kinds, and copolymers of acrylic monomers and other monomers. ..

[Methyl resin]
The mass average molecular weight of the methacryl resin is preferably 10,000 to 30,000. In the present specification, "molecular weight", "mass average molecular weight", "number average molecular weight" and "molecular weight distribution index" for methacrylic resin are measured by gel permeation chromatography (GPC), respectively, and are standard polymethyl methacrylate. (PMMA) means converted molecular weight.

The methacrylic resin is a homopolymer or copolymer containing a monomer unit derived from methyl methacrylate as a main component. Since the methacrylic resin has good transparency and weather resistance, it preferably contains 55% by mass or more of a monomer unit derived from methyl methacrylate, more preferably 60% by mass or more, and 65% by mass or more. Is even more preferable. As the methyl methacrylate, a commercially available product may be used as it is, or a product synthesized according to a conventionally known method may be used.

When the methacrylic resin is a copolymer containing a monomer unit derived from methyl methacrylate as a main component, the other monomer unit is a single amount derived from a (meth) acrylic acid ester other than methyl methacrylate. The body unit can be mentioned. The content of the monomer unit derived from the (meth) acrylic acid ester other than methyl methacrylate is preferably 0.1% by mass or more, preferably 0.1 to 45% by mass, and 10 to 10% by mass. More preferably, it is 40% by mass.

Examples of the monomer unit derived from the (meth) acrylic acid ester other than methyl methacrylate include a group in which the alcohol residue constituting the ester has a hydrocarbon ring structure. Specifically, it is represented by the formula (I). Examples thereof include monomeric units derived from the represented (meth) acrylic acid ester.

（式中、
Ｒ^１は、水素原子またはメチル基を表す。
Ｒ^２は、炭化水素環構造を有する基を表す。）

(During the ceremony,
R ¹ represents a hydrogen atom or a methyl group.
R ² represents a group having a hydrocarbon ring structure. )

The methacrylic resin contains a monomer unit derived from methyl methacrylate and a monomer unit derived from the (meth) acrylic acid ester represented by the formula (I), so that the compatibility with the polycarbonate resin is improved. It will be improved.

As the (meth) acrylic acid ester represented by the formula (I), a commercially available product may be used as it is, or a product synthesized according to a conventionally known method may be used.

R ¹ is preferably a methyl group.

Groups having a hydrocarbon ring structure of R ² include an alkyl group substituted with a cycloalkyl group, a cycloalkyl group, a cycloalkyl group substituted with an alkyl group, an alkyl group substituted with a phenyl group, a phenyl group, an alkyl group It is preferable to represent a phenyl group substituted with, an alkyl group substituted with a naphthyl group, a naphthyl group, a naphthyl group substituted with an alkyl group, a dicyclopentanyl group or a dicyclopentenyl group.

When R ² is an alkyl group substituted with a cycloalkyl group, an alkyl group substituted with a phenyl group, or an alkyl group substituted with a naphthyl group, each alkyl group may have 1 to 4 carbon atoms. .. Examples of such an alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group and a tert-butyl group.

When R ² is an alkyl group substituted with a cycloalkyl group, the cycloalkyl group may have 5 to 12 carbon atoms. Examples of such a cycloalkyl group include a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, and a cyclododecyl group. As the alkyl group substituted with a cycloalkyl group represented by R ^2, for example, a methyl group in which at least one hydrogen atom is substituted with a cycloalkyl group of the above carbon atoms 5 to 12, ethyl group, n- propyl group , Isobutyl group, n-butyl group, isobutyl group, tert-butyl group.

As the alkyl group substituted with a phenyl group represented by R ^2, for example, a methyl group in which at least one hydrogen atom is substituted with a phenyl group, an ethyl group, n- propyl group, an isopropyl group, n- butyl group, isobutyl A group, a tert-butyl group, and more specifically, a benzyl group and a phenethyl group can be mentioned.

As the alkyl group substituted with a naphthyl group represented by R ^2, for example, a methyl group in which at least one hydrogen atom is substituted with a naphthyl group, an ethyl group, n- propyl group, an isopropyl group, n- butyl group, isobutyl Groups and tert-butyl groups are mentioned, and more specific examples thereof include 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group and 2-naphthylethyl group.

When R ² is a cycloalkyl group, the cycloalkyl group may have 5 to 12 carbon atoms. Examples of such a cycloalkyl group include a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, and a cyclododecyl group. These cycloalkyl groups may have substituents such as a hydroxyl group, an amino group, and a sulfonic acid group, if necessary.

When R ² is a cycloalkyl group substituted with an alkyl group, the cycloalkyl group may have 5 to 12 carbon atoms. Examples of such a cycloalkyl group include the same groups as described above. The alkyl group which is a substituent of the cycloalkyl group may have 1 to 4 carbon atoms. Examples of such an alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group and a tert-butyl group. Examples of the cycloalkyl group substituted with the alkyl group represented by R ² include a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclol group in which at least one hydrogen atom is substituted with the above-mentioned alkyl group having 1 to 4 carbon atoms. Examples thereof include an octyl group and a cyclododecyl group.

When R ² is an alkyl-substituted phenyl group or an alkyl group-substituted naphthyl group, the alkyl group bonded to the phenyl group or naphthyl group may have 1 to 4 carbon atoms. Examples of such an alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group and a tert-butyl group.

As the phenyl group substituted with an alkyl group represented by R ^2, and more specifically, o- tolyl, m- tolyl group and a p- tolyl group. More specific examples of the naphthyl group substituted with the alkyl group represented by R ^{2 include a methylnaphthyl group and an ethylnaphthyl group.}

When R ² is a phenyl group or a naphthyl group, the phenyl group and the naphthyl group may have a substituent such as a hydroxyl group, an amino group or a sulfonic acid group, if necessary.

When R ² is a dicyclopentanyl group or a dicyclopentenyl group, these groups may have substituents such as an alkyl group, a hydroxyl group, an amino group and a sulfonic acid group, if necessary. .. The alkyl group, which is a substituent, may have 1 to 4 carbon atoms. Examples of the alkyl group as the substituent include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group and a tert-butyl group.

R ² is preferably a cycloalkyl group, a benzyl group, a dicyclopentanyl group, a phenyl group or a naphthyl group, more preferably a cyclohexyl group, a phenyl group or a naphthyl group, and even more preferably a cyclohexyl group or a cyclohexyl group. It is a phenyl group.

Preferred specific examples of the (meth) acrylic acid ester represented by the formula (I) include cyclohexyl methacrylate, benzyl methacrylate, dicyclopentanyl methacrylate, phenyl methacrylate and naphthyl methacrylate. Among these, cyclohexyl methacrylate, dicyclopentanyl methacrylate, phenyl methacrylate or naphthyl methacrylate are preferable, and cyclohexyl methacrylate or phenyl methacrylate is more preferable.

The (meth) acrylic acid ester represented by the formula (I) may be used alone or in combination of two or more.

When methyl methacrylate and the (meth) acrylic acid ester represented by the formula (I) are copolymerized, the content of the monomer unit derived from the (meth) acrylic acid ester represented by the formula (I). Is preferably 10 to 40% by mass, and more preferably 15 to 35% by mass. When two or more kinds of (meth) acrylic acid esters represented by the formula (I) are used in combination, the total content of the monomer units derived from the (meth) acrylic acid ester represented by the formula (I) is 10. It is preferably ~ 40% by mass, and more preferably 15 to 35% by mass.

Further, the methacrylic resin can contain a monomer unit derived from a (meth) acrylic acid ester other than methyl methacrylate (excluding the (meth) acrylic acid ester represented by the formula (I)). A preferred form of the (meth) acrylic acid ester (excluding methyl methacrylate and the (meth) acrylic acid ester represented by the formula (I)) is alkyl (meth) acrylic acid. As the alkyl (meth) acrylate, a commercially available product may be used as it is, or a product synthesized according to a conventionally known method may be used.

The alkyl (meth) acrylate is not particularly limited as long as it can be copolymerized with methyl methacrylate. For example, an alkyl acrylate having an alkyl moiety having 1 to 12 carbon atoms and an alkyl moiety having 2 to 12 carbon atoms. Alkyl methacrylate is mentioned. The alkyl moiety may be linear or branched.

Specific examples of the alkyl (meth) acrylate include methyl acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, and (meth) acrylic. Examples thereof include n-butyl acid acid, isobutyl (meth) acrylate, sec-butyl (meth) acrylate, tert-butyl (meth) acrylate, and 2-ethylhexyl (meth) acrylate. Among these, alkyl (meth) acrylate having an alkyl moiety having 1 to 4 carbon atoms is preferable, alkyl (meth) acrylate having an alkyl moiety having 1 to 3 carbon atoms is more preferable, and methyl acrylate, (meth). Ethyl acrylate or butyl (meth) acrylate is more preferred, and methyl acrylate, ethyl acrylate or butyl acrylate are particularly preferred. These alkyl (meth) acrylates may be used alone or in combination of two or more.

When methyl methacrylate and alkyl (meth) acrylate (excluding methyl methacrylate and the (meth) acrylic acid ester represented by the formula (I)) are copolymerized, a simple substance derived from alkyl (meth) acrylate is used. The content of the body unit is preferably 0.1 to 45% by mass, preferably 0.1 to 35% by mass, preferably 0.1 to 30% by mass, and 0.1. It is preferably ~ 25% by mass, more preferably 0.1 to 15% by mass, further preferably 0.1 to 5% by mass, and particularly preferably 0.1 to 1% by mass. It is preferably 0.4 to 0.8% by mass, and particularly preferably 0.4 to 0.8% by mass.

Methyl methacrylate, (meth) acrylic acid ester represented by the formula (I), and alkyl (meth) acrylate (excluding methyl methacrylate and the (meth) acrylic acid ester represented by the formula (I)). May be copolymerized. The alkyl (meth) acrylate is preferably methyl acrylate. In this case, the content of the monomer unit derived from methyl methacrylate is 55% by mass or more, and the content of the monomer unit derived from the (meth) acrylic acid ester represented by the formula (I) is 10. It is preferably ~ 40% by mass, the monomer unit derived from alkyl (meth) acrylate is preferably 0.1 to 35% by mass, and the content of the monomer unit derived from methyl methacrylate is 60% by mass. % Or more, and the content of the monomer unit derived from the (meth) acrylic acid ester represented by the formula (I) is 10 to 35% by mass, and the monomer derived from the alkyl (meth) acrylate. The unit is more preferably 0.1 to 30% by mass, the content of the monomer unit derived from methyl methacrylate is 65% by mass or more, and the (meth) acrylic acid represented by the formula (I). It is more preferable that the content of the monomer unit derived from the ester is 15 to 30% by mass, and the monomer unit derived from alkyl (meth) acrylate is 0.1 to 25% by mass.

Methacrylic resins are methyl methacrylate, (meth) acrylic acid ester represented by formula (I) and alkyl (meth) acrylate (excluding methyl methacrylate and (meth) acrylic acid ester represented by formula (I)). It may contain a monomer unit based on a monomer other than the above.

There is no limitation on the polymerization method when polymerizing the monomer, and for example, known polymerization methods such as bulk polymerization, solution polymerization, suspension polymerization, and emulsion polymerization can be adopted. A radical polymerization initiator is usually used for the polymerization, and a chain transfer agent is preferably used in addition to the radical polymerization initiator.

As the radical polymerization initiator, for example, an azo compound such as azobisisobutyronitrile, a lauroyl peroxide, and an organic peroxide such as 1,1-di (tert-butylperoxy) cyclohexane are preferably used. The polymerization initiator may be used alone or in combination of two or more. The amount of the polymerization initiator used may be appropriately determined according to the type of the monomer and the ratio thereof.

As the chain transfer agent, for example, mercaptans such as n-butyl mercaptan, n-octyl mercaptan, n-dodecyl mercaptan, and 2-ethylhexylthioglycolate are preferably used. The chain transfer agent may be used alone or in combination of two or more. The amount of the chain transfer agent used may be appropriately determined according to the type of monomer and its ratio.

The polymerization temperature, polymerization time, etc. when polymerizing the monomer may be appropriately set according to the type of monomer, the proportion of the monomer, and the like, and are not particularly limited.

The mass average molecular weight of the methacryl resin is preferably 10,000 to 30,000, more preferably 10,000 to 20,000. Such a methacrylic resin has excellent fluidity and can be easily melt-kneaded when mixed with a polycarbonate resin. Further, such a methacrylic resin is excellent in processability, and a molded product using such a methacrylic resin is excellent in transparency.

Two or more kinds of methacrylic resins having different mass average molecular weights may be used in combination. The method of mixing two or more kinds of methacryl resins is not particularly limited, and for example, a melt kneading method, a solvent kneading method, a dry blend method and the like can be adopted, but from the viewpoint of productivity, melt kneading can be adopted. The method or the dry blend method is preferably used. A normal mixer or kneader can be used to mix two or more types of methacrylic resin. Specifically, a uniaxial kneading extruder, a twin screw kneading extruder, a ribbon blender, a Henschel mixer, a tumbler mixer, and a drum. A tumbler or the like can be used. The two or more kinds of methacrylic resins may be mixed individually, or may be mixed with the polycarbonate resin at the same time.

The methacrylic resins having different mass average molecular weights may have different composition of monomer units.

[Resin composition]
The resin composition contains a (meth) acrylic resin and a polycarbonate resin, and the content of the (meth) acrylic resin is 5 to 40 with respect to a total content of 100 parts by mass of the (meth) acrylic resin and the polycarbonate resin. It is a part by mass, and the content of the polycarbonate resin is 60 to 95 parts by mass. The content of the (meth) acrylic resin is preferably 20 to 40 parts by mass, and the content of the polycarbonate resin is preferably 60 to 80 parts by mass. When the content of the (meth) acrylic resin exceeds 40 parts by mass, the impact resistance of the molded product obtained by injection molding the resin composition is lowered.

In addition to (meth) acrylic resin and polycarbonate resin, the resin composition includes ultraviolet absorbers, antioxidants, compatibilizers, stabilizers, colorants, foaming agents, lubricants, mold release agents, antistatic agents, and flame retardants. , Additives such as flame retardant aid may be contained. Further, the resin composition may contain a thermoplastic resin in addition to the (meth) acrylic resin and the polycarbonate resin. The additive and the thermoplastic resin may be added at the time of melt-kneading of the resin mixture containing the (meth) acrylic resin and the polycarbonate resin, may be added before the melt-kneading, or may be added after the melt-kneading. When the additive or thermoplastic resin is mixed, the total content of the (meth) acrylic resin and the polycarbonate resin should be 70 to 99.995 parts by mass with respect to 100 parts by mass of the total amount of the resin composition. Is preferable.

Examples of the ultraviolet absorber include a triazine-based ultraviolet absorber, a benzophenone-based ultraviolet absorber, a benzotriazole-based ultraviolet absorber, a benzoate-based ultraviolet absorber, and a cyanoacrylate-based ultraviolet absorber. These may be used alone or in combination of two or more.

Specific examples of the triazine-based ultraviolet absorbers include 2,4-diphenyl-6- (2-hydroxy-4-methoxyphenyl) -1,3,5-triazine and 2,4-diphenyl-6- (2-hydroxy). -4-ethoxyphenyl) -1,3,5-triazine, 2,4-diphenyl-6- (2-hydroxy-4-propoxyphenyl) -1,3,5-triazine, 2,4-diphenyl-6- (2-Hydroxy-4-butoxyphenyl) -1,3,5-triazine, 2,4-diphenyl-6- (2-hydroxy-4-hexyloxyphenyl) -1,3,5-triazine, 2,4 −Diphenyl-6- (2-hydroxy-4-octyloxyphenyl) -1,3,5-triazine, 2,4-diphenyl-6- (2-hydroxy-4-dodecyloxyphenyl) -1,3,5 -Triazine, 2,4-diphenyl-6- (2-hydroxy-4-benzyloxyphenyl) -1,3,5-triazine, 2,4-bis (2,4-dimethylphenyl) -6- (2-) Hydrox-4-octyloxyphenyl) -1,3,5-triazine and 2,4,6-tris (2-hydroxy-4-hexyloxy-3-methyl) -1,3,5-triazine can be mentioned.

Specific examples of the benzophenone-based ultraviolet absorber include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octyloxybenzophenone, 2-hydroxy-4-dodecyloxybenzophenone, and 2, -Hydroxy-4-octadecyloxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2,2', 4,4'-tetrahydroxybenzophenone Can be mentioned.

Specific examples of the benzotriazole-based ultraviolet absorber include 2- (2-hydroxy-5-methylphenyl) benzotriazole, 2- (2-hydroxy-3,5-di-tert-butylphenyl) benzotriazole, 2-. (2-Hydroxy-3-tert-butyl-5-methylphenyl) benzotriazole, 2- (2-hydroxy-5-methylphenyl) benzotriazole, 2- (2-hydroxy-3,5-di-tert-butyl) Phenyl) benzotriazole, 2- (2-hydroxy-3,5-di-tert-butylphenyl) -5-chlorobenzotriazole, 2- [2-hydroxy-3- (3,4,5,6-tetrahydrophthalimide) Methyl) -5-methylphenyl] benzotriazole, 2,2'-methylenebis [4- (1,1,3,3-tetramethylbutyl) -6- (2H-benzotriazole-2-yl) phenol], 2 -(2-Hydroxy-3-tert-butyl-5-methylphenyl) -5-chlorobenzotriazole, 2- (2-hydroxy-3,5-di-tert-amylphenyl) -5-chlorobenzotriazole, etc. Be done.

Specific examples of the benzoate-based ultraviolet absorber include 2,4-di-tert-butylphenyl 3', 5'-di-tert-butyl-4'-hydroxybenzoate, and 2,6-di-tert-butylphenyl 3. ', 5'-Di-tert-butyl-4'-hydroxybenzoate, n-hexadecyl 3,5-di-tert-butyl-4-hydroxybenzoate, n-octadecyl 3,5-di-tert-butyl-4- Hydroxybenzoate can be mentioned.

Specific examples of the cyanoacrylate-based ultraviolet absorber include 2'-ethylhexyl 2-cyano-3,3-diphenyl acrylate and ethyl 2-cyano-3- (3,4-methylenedioxyphenyl) acrylate.

Most of these UV absorbers are commercially available, and are triazine-based UV absorbers "KEMISORB 102" sold by Chemipro Kasei Co., Ltd. and triazine-based UV absorbers sold by ADEKA Corporation. Those having a relatively large molecular weight, such as "ADEKA STAB LA-F70" and "ADEKA STAB LA-31", which is a benzotriazole-based ultraviolet absorber sold by ADEKA Corporation, are preferable.

The molecular weight of the ultraviolet absorber (in the case of a mixture or oligomer, the mass average molecular weight) is preferably in the range of 500 to 1,000, more preferably in the range of 550 to 700. If the molecular weight of the ultraviolet absorber is small, it tends to volatilize during molding, while if the molecular weight of the ultraviolet absorber is large, the compatibility with the (meth) acrylic resin or polycarbonate resin tends to decrease.

Examples of the antioxidant include a hindered phenol-based antioxidant, a phosphorus-based antioxidant, and a sulfur-based antioxidant. These antioxidants also function as heat stabilizers for (meth) acrylic or polycarbonate resins. These may be used alone or in combination of two or more.

Various types of hindered phenolic antioxidants are commercially available. Examples of commercially available products are "IRGANOX 1010", "IRGANOX 1035", "IRGANOX 1076" and "IRGANOX 1222" sold by BASF. , "Sumirazer GM", "Sumilyzer GS" and "Sumirazer GA80" sold by Sumitomo Chemical Co., Ltd., "Adekastab AO-70" and "Adekastab AO-80" sold by ADEKA Corporation, etc. There is.

Specific examples of phosphorus-based antioxidants include tris (2,4-di-tert-butylphenyl) phosphite, 2-[{2,4,8,10-tetrakis (1,1-dimethylethyl) dibenzo. [D, f] [1,3,2] dioxaphosphine-6-yl} oxy] -N, N-bis [2-[{2,4,8,10-tetrakis (1,1-dimethyl) Ethyl) Dibenzo [d, f] [1,3,2] dioxaphosphine-6-yl} oxy] -ethyl] etanamin, diphenyltridecylphosphite, triphenylphosphine, 2,2'-methylenebis (ethyl) There are 4,6-di-tert-butylphenyl) octylphosphine, bis (2,6-di-tert-butyl-4-methylphenyl) pentaeristol diphosphite and the like. Among these, 2,2'-methylenebis (4,6-di-tert-butylphenyl) octylphosphite is preferable.

Specific examples of sulfur-based antioxidants include dimethyl disulfide, diethyl disulfide, di-n-propyl disulfide, di-n-butyl disulfide, di-sec-butyl disulfide, di-tert-butyl disulfide, and di-tert-. There are amyl disulfide, dicyclohexyl disulfide, di-tert-octyl disulfide, di-n-dodecyl disulfide, di-tert-dodecyl disulfide and the like. Among these, di-tert-alkyl disulfide is preferable, and di-tert-dodecyl disulfide is more preferable.

In addition to the antioxidants described above, aromatic amine compounds known as antioxidants for rubber can also be used as heat stabilizers for methacrylic resins or resin compositions. Specific examples of aromatic amine-based heat stabilizers (anti-aging agents) include N, N'-diphenyl-p-phenylenediamine, N-phenyl-N'-isopropyl-p-phenylenediamine, 2,2. There are polymers of 4-trimethyl-1,2-dihydroquinoline and the like. These are sold by Sumitomo Chemical Co., Ltd. under the trade names of "ANTIGENE P", "ANTIGENE 3C", and "ANTIGENE FR", respectively.

The glass transition temperature (Tg ^resin , ° C.) of the resin composition is preferably 100 to 150 ° C., more preferably 110 to 150 ° C.

In the resin composition, the temperature (cloud point) at which phase separation of the resin starts and becomes cloudy is preferably 280 ° C. or higher, more preferably 300 ° C. or higher.

The resin composition preferably has a viscosity value of 5000 Pa · s or less at 230 ° C. and a shear rate of 100 sec- ¹ o'clock, and a viscosity value of 3000 Pa · s or less at 250 ° C. and a shear rate of 100 sec- ¹ o'clock. It is preferable that the viscosity value at 270 ° C. and a shear rate of 100 sec- ¹ is 1000 Pa · s or less.

[Manufacturing method of resin composition]
The resin composition can be produced by melt-kneading a resin mixture containing a (meth) acrylic resin and a polycarbonate resin. Melt kneading is usually carried out under temperature conditions of 180 to 320 ° C., preferably 200 to 300 ° C., at ^{a shear rate of usually 10 to 200 sec -1} , preferably 30 to 150 sec ^-1.

For melt-kneading of a resin mixture containing a (meth) acrylic resin and a polycarbonate resin, a device known as an ordinary mixer or a kneader can be used. Specific examples thereof include a single-screw kneading extruder, a twin-screw kneading extruder, a ribbon blender, a Henschel mixer, a Banbury mixer, a drum tumbler, and the like. Among these, a twin-screw kneading extruder is preferable. Further, the melt-kneading can be carried out in an atmosphere of an inert gas such as nitrogen gas, argon gas or helium gas, if necessary.

[Molded product]
The molded product of the present embodiment contains a (meth) acrylic resin and a polycarbonate resin, and the content of the (meth) acrylic resin is higher than the total content of 100 parts by mass of the (meth) acrylic resin and the polycarbonate resin. It includes a step of injection molding a resin composition having 5 to 40 parts by mass and a polycarbonate resin content of 60 to 95 parts by mass under specific conditions satisfying the following formula (1).

Tg ^resin +30 ≧ T ^mold ≧ Tg ^resin -15

(In the formula, T ^mold represents the temperature (° C.) of the mold in contact with the injected resin composition. Tg ^resin represents the glass transition temperature (° C.) of the resin composition.)

The manufacturing method of the first embodiment of the present invention uses injection molding, which will be described with reference to FIG. The injection molding machine (1) has a hopper (2) for supplying pellets (4) of the resin composition, and a cylinder (6) for melting the resin pellets (4). The tip of the cylinder (6) is connected to the mold (11). The mold (11) has a space inside which a resin is filled to obtain a molded product. Resin pellets (4) are supplied from pellets (2). The pellet (4) is melted in the cylinder (6), and the resin (4) is supplied (or injected) to the mold (11) from the tip of the cylinder. The mold (11) is filled with the resin (4) to produce a molded product. In the production method of the embodiment of the present invention, for example, when the resin is supplied from the cylinder (6) to the mold (11), the Tg of the resin composition and the temperature of the mold (11) are set to the formula (1). Including the step of injection molding under specific conditions to be met.

In the injection molding step, the injection temperature for injection is preferably 230 ° C. to 300 ° C. The mold temperature is preferably 80 ° C. or higher, more preferably 100 ° C. or higher, and further preferably 120 ° C. or higher.

When the mold temperature is 100 ° C. or higher, heat and cool molding is preferable as the injection molding step. Heat-and-cool molding refers to a manufacturing method in which a molten resin composition is injected into a mold in which the surface of the mold is heated in advance, and then the mold is cooled to take out a molded product. Explaining the heat-and-cool molding with reference to FIG. 1, for example, after heating the mold (11) in advance, the resin composition is supplied from the cylinder (6) to the heated mold (11). After that, the mold (11) is cooled and the molded product is taken out. In particular, it is preferably used in the case of producing a thin-walled molded product or a molded product having a weld portion, and an injection molded product having a high appearance can be obtained more easily. The mold temperature during heating is preferably 100 to 180 ° C, and the temperature during cooling is preferably 50 ° C to 80 ° C.

In the embodiment of the present invention, when heat and cool molding is performed, ^{it is preferable that the temperature of the preheated mold} (also referred to as T mold (H)) satisfies the above formula (1). That is, ^{it is preferable that Tg resin} +30 ≧ T ^mold (H) ≧ Tg ^{resin -15, and the temperature of the cooled mold} (T mold (C)) at the time of taking out the molded product does not necessarily have the formula (1). There is no need to meet.

The injection speed is preferably 10 mm / s to 300 mm / s, more preferably 10 mm / s to 100 mm / s, and even more preferably 10 mm / s to 50 mm / s.

Volume flow is ^preferably 20cm ³ ~600cm ^3, more preferably 20cm ³ ~200cm ^3, further preferably 20 cm 3 100 cm ^3.

The injection pressure is preferably 100 MPa to 300 MPa.

The holding pressure is preferably 50 MPa to 200 MPa.

The molded body of this embodiment is useful as an electro-optical material (material for lenses, optical disk substrates, light guide plates, etc.), cover material (material for covers such as displays), materials for medical products / cosmetic containers, resin glazing materials, and the like. Is.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to these examples. In the examples, the portion indicating the amount used or the content,% and ppm are based on mass unless otherwise specified. The methods for measuring and evaluating various physical properties of the resin composition and the molded product are as follows.

[Molecular weight of methacryl resin]
The molecular weight of the methacryl resin was determined using a gel permeation chromatograph [“HLC-8320GPC EcoSEC” manufactured by Tosoh Corporation]. The measurement conditions were such that tetrahydrofuran was circulated as a mobile phase on a column maintained at 40 ° C. at a flow rate of 0.350 mL / min and detected by an RI (differential refractometer) detector to obtain a chromatogram. The columns used were two "TSKgel SuperMultipore HZ-M" manufactured by Tosoh Corporation and one "TSKgel SuperHZ2500" connected in series. For the quantification of the molecular weight, a calibration curve was prepared using a set of standard PMMA "STANDARD M-75" manufactured by Showa Denko KK, and the molecular weight was calculated based on the chromatogram value and the calibration curve.

[Cloud point of resin composition]
A resin composition produced by mixing a methacrylic resin and a polycarbonate resin is dried at 90 ° C. for 12 hours, and then a press molding machine [“Shinto type ASF type hydraulic press” manufactured by Shinto Metal Industry Co., Ltd.] is used. The press molding was performed at a press temperature of 220 ° C. to obtain at least five molded pieces having a thickness of 3 mm. Next, the obtained molded pieces were press-molded again using the same press molding machine at press temperatures of 280 ° C., 290 ° C., 300 ° C., 310 ° C. and 320 ° C., and each test having a thickness of 2 mm and a 40 mm square was performed. I got a piece. The appearance of each of the obtained test pieces was visually evaluated, and the highest press temperature among the press temperatures at which a transparent test piece without white turbidity was obtained was defined as the cloud point of the resin composition.

[Glass transition temperature of resin composition]
^{The glass transition temperature (Tg resin} , ° C.) of the resin composition produced by mixing the methacrylic resin and the polycarbonate resin was measured according to JIS-K7121. For the measurement, a differential scanning calorimeter (“DSC7020” manufactured by Hitachi High-Tech Science Corporation) was used under the condition of a nitrogen gas flow rate of 50 mL / min. First, the temperature is raised from room temperature (23 ° C.) to 150 ° C. (primary temperature rise) at 20 ° C./min and held at 150 ° C. for 5 minutes to completely melt the resin composition, and then 10 ° C./min. The temperature was lowered from 150 ° C. to −35 ° C., held at −35 ° C. for 1 minute, and then raised again to 210 ° C. at 10 ° C./min (secondary temperature rise). Of the DSC curves drawn during this period, the intersection (intermediate point glass transition temperature) between the stepwise change partial curve at the time of secondary temperature rise and the straight line at equal distances in the vertical axis direction from each baseline extension line is the glass transition temperature. It was measured as (Tmg) (° C.). The measurement was performed twice per resin composition, and the arithmetic mean (rounded to the nearest whole number) of the two values was used as the measured value.

[Appearance of molded product]
The appearance of the molded product was visually evaluated. In Table 2, those having almost no cloudy area of the molded product were indicated by "⊚", those that could be confirmed lightly were indicated by "○", and those that were significantly cloudy were indicated by "x".

[Synthetic example]: Production of methacrylic resin (A-1) In a reactor having an internal volume of 200 liters, 95.4 kg of ion-exchanged water, 48 g of polysodium polymethacrylate (1% aqueous solution viscosity: 30 Stokes) as a suspension stabilizer, An aqueous phase consisting of 7.7 g of hydroxypropylmethylcellulose (“Metro's 90SH” manufactured by Shin-Etsu Chemical Co., Ltd.), 230 g of sodium dihydrogen phosphate (anhydrous), and 269 g of sodium dihydrogen phosphate (hepatohydrate) was charged. After that, 44.7 kg (73% by mass) of methyl methacrylate, 13.4 kg (22% by mass) of cyclohexyl methacrylate, 2.6 kg (4% by mass) of phenyl methacrylate, 320 g (0.5% by mass) of methyl acrylate, An oil phase consisting of 448 g of lauroyl peroxide and 2.56 kg of n-octyl mercaptan was charged. Then, while stirring at 250 rpm, the temperature was raised to 83 ° C., held for 1.5 hours, and then cooled to room temperature. The obtained slurry was injected into a tank containing water → separation → injected into a tank containing water → solid-liquid separation was performed by a separation centrifuge, and granular beads were collected as a solid. The collected granular beads were placed in a large vat, 4800 g of ion-exchanged water was added thereto, and the mixture was stirred for 5 minutes, then solid-liquid separated by a centrifuge again, and a series of washing operations for collecting the granular beads was repeated three times. .. The washed granular beads were dried under reduced pressure in a vacuum dryer set at 60 ° C. to obtain a methacrylic resin (A-1). The weight average molecular weight was 12,000.

Polycarbonate resin (B-1)
As the polycarbonate resin (B-1), "SD Polyca 301-10" sold by Sumika Polycarbonate Limited, Melt Volume Flow Rate MVR = 10 g / 10 minutes] was used.

[Production Examples 1 and 2]: Resin Composition Containing Methacrylic Resin and Polycarbonate Resin A biaxial kneader (trade name "TEX-30", stock name "TEX-30") is prepared by mixing a methacrylic resin and a polycarbonate resin according to the composition ratios shown in Table 1. Using a company manufactured by Japan Steel Works, Ltd., melt-kneading was performed at a rotation speed of 150 rpm (shearing speed 122 sec-1) and 250 ° C. After melt-kneading, the obtained melt was extruded into a strand shape, cooled, and cut with a strand cutter to prepare a pellet-shaped resin composition.

[Examples 1 to 4 and Comparative Example 1]
Heat and cool molding was carried out under the following conditions, and the appearance of the obtained molded product was evaluated.
Equipment: NADEM2800II-DM (manufactured by Meiki Seisakusho Co., Ltd.)
Mold: 248 mm x 198 mm x 3 mm
Injection temperature: 230 ° C, 250 ° C
Injection pressure: 200 MPa
Rotation speed: 100 rpm
Holding pressure: 130 MPa
Mold temperature (high temperature, at the time of injection): 80 ° C, 120 ° C, 140 ° C
Mold temperature (low temperature, at the time of removal): 80 ° C

It can be seen that the resin compositions of Production Examples 1 and 2 obtained in Table 1 were able to suppress white turbidity by setting the mold temperature in a specific temperature range in Examples 1 to 8 as shown in Table 2. ..
For example, the molded product of Example 8 is shown in FIG. 2 (A), and the molded product of Comparative Example 1 is shown in FIG. 2 (B). It can be seen that the molded product of Example 8 has almost no cloudiness over the entire surface of the molded product, whereas the molded product of Comparative Example 1 is largely cloudy on the left side and the right side of the molded product. It has been clarified that by using the production method of the example, a molded product containing a polycarbonate resin and a (meth) acrylic resin, which has a larger area and is excellent in transparency, can be produced more easily.

By using the production method of the embodiment of the present invention, a molded product containing a polycarbonate resin and a (meth) acrylic resin, which has a larger area and is excellent in transparency, can be produced more easily and more efficiently. Optimal optical characteristics such as heat resistance, impact resistance, chemical resistance, hygroscopicity, surface hardness, and birefringence characteristics are suitable in combination with polycarbonate resin while maintaining the original excellent transparency of (meth) acrylic resin. It is possible to manufacture an improved molded product.

1 Injection molding machine 2 Hopper 4 Pellet 6 Cylinder 11 Mold

Claims (7)

Contains (meth) acrylic resin and polycarbonate resin,
A resin having a (meth) acrylic resin content of 5 to 40 parts by mass and a polycarbonate resin content of 60 to 95 parts by mass with respect to a total content of 100 parts by mass of the (meth) acrylic resin and the polycarbonate resin. The composition,
A method for producing a molded product, which comprises a step of injection molding under the condition of satisfying the following formula (1).

Tg ^resin -15 ≤ T ^mold ≤ Tg ^resin +30 (1)
(During the ceremony,
Tg ^resin represents the glass transition temperature (° C.) of the resin composition.
T ^mold represents the temperature (° C.) of the mold that comes into contact with the injected resin composition. ) The (meth) acrylic resin
Monomer unit derived from methyl methacrylate is 55% by mass or more.
The monomer unit based on the (meth) acrylic acid ester represented by the following formula (I) is 10 to 40% by mass.
Contains 0.1 to 35% by weight of monomeric units based on alkyl (meth) acrylate (excluding methyl methacrylate and the (meth) acrylic acid ester represented by formula (I)).
The method for producing a molded product according to claim 1.

(During the ceremony,
R ¹ represents a hydrogen atom or a methyl group.
R ² represents a group having a hydrocarbon ring structure. ) ^{R 2 of} formula (I) is substituted with an alkyl group substituted with a cycloalkyl group, a cycloalkyl group, a cycloalkyl group substituted with an alkyl group, an alkyl group substituted with a phenyl group, a phenyl group, or an alkyl group. The method for producing a molded product according to claim 2, which represents a phenyl group, an alkyl group substituted with a naphthyl group, a naphthyl group, a naphthyl group substituted with an alkyl group, a dicyclopentanyl group or a dicyclopentenyl group. The method for producing a molded product according to claim 2, wherein the (meth) acrylic acid ester represented by the formula (I) is cyclohexyl methacrylate, benzyl methacrylate, phenyl methacrylate or naphthyl methacrylate. The method for producing a molded product according to any one of claims 2 to 4, wherein the alkyl (meth) acrylate is methyl acrylate. The method for producing a molded product according to any one of claims 1 to 5, wherein the polycarbonate resin is an aromatic polycarbonate resin. The method for producing a molded product according to any one of claims 1 to 6, wherein the injection molding step is heat and cool molding.

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