JP2016008278A - Polycarbonate resin composition and molded article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polycarbonate resin composition which can obtain a molded article having excellent heat resistant colorability, flame retardancy and impact resistance and has low corrosiveness to a metal, and to provide a molded article.SOLUTION: There is provided a polycarbonate resin composition which comprises a polycarbonate resin, a fire retardant, a polytetrafluoroethylene and a rubbery graft polymer, where in the rubbery graft polymer, a rubbery part contains 50 mass% or more of diene structural units and/or 86 mass% or more of alkyl(meth)acrylate structural units, the total amount of sulfate ions and sulfite ions contained in water which are extracted with hot water from the rubbery graft polymer is 3.5 ppm or less and the content of chlorine ions contained in the rubbery graft polymer is 150 ppm or less.

Description

  The present invention relates to a polycarbonate resin composition and a molded article.

  Polycarbonate resin is a general-purpose engineering plastic that excels in transparency, impact resistance, heat resistance, dimensional stability, etc., and its excellent characteristics make it an excellent choice for automobiles, OA equipment such as printers, and electrical and electronic fields such as mobile phones. It is widely used industrially as a material. These materials have recently been thinned year by year for the purpose of reducing the size, weight, and functionality. Therefore, there is a demand for a resin material that is excellent in mechanical properties such as sufficient impact resistance and exhibits excellent heat-resistant coloring property and heat-and-moisture resistance even in a molded product that is thinned and lightened.

For example, Patent Document 1 discloses a polycarbonate resin composition comprising a polycarbonate resin, a rubbery copolymer, a flame retardant, and a fiber-forming fluorine-containing polymer.
Patent Document 2 discloses a polycarbonate resin composition containing a polycarbonate component, a flame retardant, polytetrafluoroethylene, and an impact modifier.
Patent Document 3 discloses a polycarbonate resin composition containing an aromatic polycarbonate resin, a polyorganosiloxane-containing graft copolymer, acrylic-modified polytetrafluoroethylene, and an aromatic phosphate ester flame retardant. Yes.

JP 2003-171547 A International Publication No. 2007/0500412 International Publication No. 2013/129709

  However, molded articles obtained from the polycarbonate resin compositions described in Patent Documents 1 to 3 do not sufficiently satisfy all of the heat resistance coloring property, flame retardancy, and impact resistance. In addition, when injection molding the polycarbonate resin composition, metal pipes on the production line, molds of molding machines, and the like may be corroded.

  The present invention has been made in view of the above circumstances, and can obtain a molded article excellent in heat-resistant colorability, flame retardancy, and impact resistance, and a polycarbonate resin composition having low corrosiveness to metals, and a molded article. The purpose is to provide.

The present invention has the following aspects.
[1] A polycarbonate resin composition comprising a polycarbonate resin, a flame retardant, polytetrafluoroethylene, and a rubbery graft polymer, wherein the rubbery graft polymer has a diene structural unit of 50 A total amount of sulfate ion and sulfite ion contained in water which is a polymer containing at least 86% by mass or 86% by mass or more of an alkyl (meth) acrylate structural unit and extracted from the rubbery graft polymer by hot water extraction by the following extraction treatment Is 3.5 ppm or less, and the content of chlorine ions contained in the rubber-like graft polymer is 150 ppm or less.
(Extraction process)
200 ml of deionized water is added to 20.0 g of the rubbery graft polymer and extracted at 95 ° C. for 20 hours.
[2] A molded product obtained by molding the polycarbonate resin composition according to [1].

  ADVANTAGE OF THE INVENTION According to this invention, the molded product excellent in heat-resistant coloring property, a flame retardance, and impact resistance can be obtained, and the polycarbonate resin composition and molded product with low corrosiveness with respect to a metal can be provided.

Hereinafter, the present invention will be described in detail.
In addition, this invention is not limited to the following embodiment, It can implement by changing variously within the range of the summary.
Moreover, in the following description, the “molded product” is obtained by molding the polycarbonate resin composition of the present invention.

"Polycarbonate resin composition"
The polycarbonate resin composition of the present invention contains a polycarbonate resin, a flame retardant, polytetrafluoroethylene, and a rubbery graft polymer.

<Polycarbonate resin>
As the polycarbonate resin, any conventionally known one can be used, and specifically, an aromatic polycarbonate resin, an aliphatic polycarbonate resin, an aromatic-aliphatic polycarbonate resin, or the like can be used.

  The polycarbonate resin is obtained, for example, by a phosgene method in which various dihydroxy diaryl compounds and phosgene are reacted, or a transesterification method in which a dihydroxy diaryl compound is reacted with a carbonate such as diphenyl carbonate. A typical polycarbonate resin includes a polycarbonate produced from 2,2-bis (4-hydroxyphenyl) propane (bisphenol A).

  Examples of the dihydroxydiaryl compound include bisphenol A, bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane, 2,2-bis (4-hydroxyphenyl) butane, and bis (4- Hydroxyphenyl) phenylmethane and the like. These may be used alone or in combination of two or more.

The viscosity average molecular weight of the polycarbonate resin is preferably 10,000 to 40,000, and more preferably 15,000 to 30,000. When the viscosity average molecular weight of the polycarbonate resin is 10,000 or more, the molecular weight is hardly lowered when the polycarbonate resin composition is molded at a high temperature, and the impact strength retention rate and heat resistance colorability of the obtained molded product are further improved. . On the other hand, when the viscosity average molecular weight of the polycarbonate resin is 40,000 or less, a polycarbonate resin composition having excellent melt fluidity can be obtained.
The “viscosity average molecular weight” is a molecular weight obtained by conversion from solution viscosity measured at a temperature of 25 ° C. using methylene chloride as a solvent.

<Flame Retardant>
As the flame retardant, almost all known flame retardants can be used, and specifically, halogenated compounds such as halogenated bisphenol A, halogenated polycarbonate oligomers, brominated epoxy compounds, and antimony oxide. Halogen flame retardants in combination with flame retardant aids; organic salt flame retardants; phosphorus flame retardants such as phosphate ester flame retardants, halogenated phosphate ester type flame retardants; metal salts of aromatic sulfonic acids, Examples include sulfonic acid-based flame retardants such as metal salts of perfluoroalkanesulfonic acid; silicone-based flame retardants such as branched-type phenyl silicone compounds and organopolysiloxanes such as phenyl silicone resins. These may be used alone or in combination of two or more.
Among these flame retardants, phosphorus-based flame retardants and sulfonic acid-based flame retardants are preferable, and phosphorus-based flame retardants are more preferable in terms of further improving the flame resistance of the obtained molded product.

  0.01-20 mass parts is preferable with respect to 100 mass parts of polycarbonate resin, and, as for content of a flame retardant, 0.1-10 mass parts is more preferable. If content of a flame retardant is 0.01 mass part or more, the flame retardance of a molded article will improve more. On the other hand, if content of a flame retardant is 20 mass parts or less, the fall of mechanical characteristics, such as impact strength of a molded article, can be suppressed.

<Polytetrafluoroethylene>
Polytetrafluoroethylene mainly plays the role of an anti-drip agent.
Polytetrafluoroethylene is a polymer having a unit represented by the following general formula (1) or a derivative thereof.
_{(-CF 2 -CF 2 -) ···} (1)

  Polytetrafluoroethylene is obtained, for example, by emulsion polymerization of a tetrafluoroethylene monomer. In the case of emulsion polymerization, fluorine-containing olefins such as hexafluoropropylene, chlorotrifluoroethylene, fluoroalkylethylene, perfluoroalkyl vinyl ether, and perfluoroalkyl are used as copolymerization components as long as the properties of polytetrafluoroethylene are not impaired. Fluorine-containing alkyl (meth) acrylates such as (meth) acrylate can be used. The ratio of these copolymer components is preferably 10 parts by mass or less with respect to 100 parts by mass of tetrafluoroethylene.

As polytetrafluoroethylene, known ones can be used, and those synthesized appropriately may be used, or commercially available products may be used. Various modified polytetrafluoroethylenes may also be used.
Examples of commercially available products of polytetrafluoroethylene include: unmodified polytetrafluoroethylene such as “Polyflon FA-500” manufactured by Daikin Industries, Ltd .; SAN modified polytetrafluoroethylene such as “BLENDEX B449” manufactured by Galata Chemicals; Examples thereof include acrylic-modified polytetrafluoroethylene such as “Methbrene A-3000”, “Methbrene A-3750”, “Methbrene A-3800” manufactured by Rayon. These may be used alone or in combination of two or more.
Among these polytetrafluoroethylenes, SAN-modified polytetrafluoroethylene and acrylic-modified are superior in that they are excellent in dispersibility in polycarbonate resin and the mechanical properties, heat resistance, and flame retardancy of the resulting molded product are further improved. Polytetrafluoroethylene is preferable, and acrylic-modified polytetrafluoroethylene is more preferable.

  The content of polytetrafluoroethylene in various modified polytetrafluoroethylenes is preferably 10 to 80% by mass and more preferably 20 to 70% by mass in 100% by mass of the modified polytetrafluoroethylene. . If this content is 10% by mass or more, the obtained molded product is more excellent in flame retardancy. On the other hand, when the content is 80% by mass or less, the resulting molded article has an excellent appearance.

The mass average molecular weight of polytetrafluoroethylene is preferably 1 million to 50 million, more preferably 3 million to 30 million. If the polytetrafluoroethylene has a mass average molecular weight of 1,000,000 or more, the melt tension when blended with the polycarbonate resin is improved, and sufficient anti-drip properties (draw-down preventing properties) are obtained. On the other hand, when the mass average molecular weight of polytetrafluoroethylene is 50 million or less, the dispersibility of polytetrafluoroethylene when blended in a polycarbonate resin is excellent, and the surface appearance of the obtained molded product is excellent.
The “mass average molecular weight” is calculated, for example, from the heat of crystallization measured by differential thermal analysis as described on page 36 of the fluorine resin handbook (Satokawa edition, Nikkan Kogyo Shimbun, 1990). Value.

  0.01-20 mass parts is preferable with respect to 100 mass parts of polycarbonate resin, and, as for content of polytetrafluoroethylene, 0.05-10 mass parts is more preferable. If content of polytetrafluoroethylene is 0.01 mass part or more, the moldability of the obtained polycarbonate resin composition and the flame retardance of the molded product obtained will be more excellent. On the other hand, when the content of polytetrafluoroethylene is 20 parts by mass or less, the dispersibility of polytetrafluoroethylene in the polycarbonate resin is excellent, and the surface appearance of the obtained molded product is excellent.

<Rubber graft polymer>
The rubber-like graft polymer mainly exhibits an effect of suppressing a decrease in heat-resistant colorability of the molded product.
The rubber-like graft polymer has a diene structural unit of 50 mass when the rubber-like portion (hereinafter also referred to as “rubber portion”) is 100 mass% of all monomer units constituting the rubber-like portion. % Or a polymer containing 86% by mass or more of an alkyl (meth) acrylate structural unit. Thereby, the impact resistance of the molded product is improved. The rubber part preferably contains 60% by mass or more of diene structural units or 90% by mass or more of alkyl (meth) acrylate structural units.

The total amount (g / g) of sulfate ion (SO ₄ ²⁻ ) and sulfite ion (SO ₃ ²⁻ ) contained in water extracted from the rubber graft polymer by hot water extraction by the following extraction process is 3.5 ppm or less. Yes, 3.0 ppm or less is preferable, and 2.5 ppm or less is more preferable.
(Extraction process)
200 ml of deionized water is added to 20.0 g of the rubbery graft polymer and extracted at 95 ° C. for 20 hours.

When a rubber-like graft polymer in which the total amount of sulfate ions and sulfite ions contained in water exceeds 3.5 ppm is added to the polycarbonate resin, the polycarbonate resin is easily decomposed by these ions. As a result, the heat resistant colorability of the molded product is lowered, or the flame retardancy is lowered.
In particular, when the rubbery part of the rubbery graft polymer contains a diene structural unit, if the total amount of sulfate ion and sulfite ion exceeds 3.5 ppm, the rubbery part (eg, butadiene rubber) is oxidized by these ions. Easy to deteriorate. As a result, the heat resistant colorability of the molded product is lowered.
If the total amount of sulfate ions and sulfite ions is 3.5 ppm or less, the heat resistant colorability and flame retardancy can be maintained.
The present invention is particularly effective when the rubbery portion contains a diene structural unit.

The content (g / g) of chlorine ions (Cl ⁻ ) contained in the rubber-like graft polymer is 150 ppm or less, preferably 100 ppm or less, and more preferably 50 ppm or less. When the content of chloride ions exceeds 150 ppm, when manufacturing a rubber-like graft polymer or when injection-molding the polycarbonate resin composition of the present invention, a metal pipe of a production line, a mold of a molding machine, etc. Corrodes.

The total amount of sulfate ions and sulfite ions, and the content of chloride ions can be adjusted by the type and amount of emulsifier and coagulant used in producing the rubber graft polymer.
Here, an example of the manufacturing method of a rubber-like graft polymer is demonstrated.

<< Rubber graft polymer production method >>
The rubber-like graft polymer is obtained by selecting an emulsifier used in the polymerization and a coagulant used in the powder recovery. For example, a vinyl monomer component is polymerized in the presence of rubber latex. can get. In particular, it is preferable to manufacture by a method including the following steps (a) to (c).
Step (a): A step of preparing a rubber latex.
Step (b): A step of obtaining a rubbery graft polymer latex by emulsion polymerization of a vinyl monomer component in the presence of a rubber latex containing an emulsifier which is a salt of a weak acid and a strong base or a nonionic emulsifier.
Step (c): A step of recovering the rubber-like graft polymer latex by spray recovery or using a coagulant which is a salt of a weak acid and a strong base.

(Process (a))
An elastomer is preferably used for the rubber part of the rubber-like graft polymer, and among these, a thermoplastic elastomer is preferably used. As the thermoplastic elastomer, various copolymer resins are used. The glass transition temperature is usually −20 ° C. or lower, preferably −30 ° C. or lower, more preferably −50 ° C. or lower, and more preferably −70 ° C. The following are more preferable.

The rubber part of the rubber-like graft polymer contains a diene structural unit and an alkyl (meth) acrylate structural unit. In particular, a polymer having a structural unit having a glass transition temperature of −20 ° C. or lower is preferable. Moreover, the rubber part may have another vinyl monomer structural unit as needed. The structural unit of the rubber part can be used alone or in combination of two or more.
Here, the diene structural unit means a structural unit derived from a diene monomer used in the production of rubber latex described later, and the alkyl (meth) acrylate structural unit means an alkyl (meta) used in the production of rubber latex. ) Means a structural unit derived from an acrylate monomer, and the other vinyl monomer structural unit means a structural unit derived from another vinyl monomer used as necessary for the production of rubber latex. .

From the viewpoint of improving the impact resistance of the molded product, the rubber part of the rubber graft polymer has a diene structural unit of 50% by mass or more when the total monomer units constituting the rubber component are 100% by mass or 86 mass% or more of alkyl (meth) acrylate structural units are included. The rubber part preferably contains 60% by mass or more of diene structural units or 90% by mass or more of alkyl (meth) acrylate structural units. In particular, from the viewpoints of low-temperature impact strength development and color developability of the polycarbonate resin composition, it is preferable to include a diene structural unit, and more preferably to include a butadiene structural unit.
When the rubber part of the rubber-like graft polymer contains a butadiene structural unit, the total monomer unit constituting the rubber part is preferably 100% by mass, and preferably contains 70% by mass or more of butadiene structural unit, and 80% by mass. % Or more is more preferable, and 90% by mass or more is more preferable. When the rubber part contains 70% by mass or more of butadiene structural units, the impact strength at low temperature of a molded product obtained from the polycarbonate resin composition is further improved.
The rubber part of the rubber-like graft polymer may contain both a diene structural unit and an alkyl (meth) acrylate structural unit. In this case, when the total monomer units constituting the rubber component are 100% by mass, it is preferable to include 90% by mass or more of these structural units in total.

  Although it does not specifically limit as a monomer (diene-type monomer) used as the raw material of a diene structural unit, For example, 1,3-butadiene is mentioned, for example, diene-type monomers, such as a butadiene and isoprene.

Although it does not specifically limit as a monomer (alkyl (meth) acrylate monomer) used as the raw material of an alkyl (meth) acrylate structural unit, For example, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate , 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, stearyl acrylate, and t-butyl acrylate. These may be used alone or in combination of two or more. Among these, from the viewpoint of polymerization stability of emulsion polymerization, an alkyl acrylate having 2 to 8 carbon atoms is preferable, an alkyl acrylate having 3 to 6 carbon atoms is more preferable, and butyl acrylate is particularly preferable.
Here, “(meth) acrylate” is a general term for “acrylate” and “methacrylate”.

  Monomers or other polyfunctional monomers that can be copolymerized with diene monomers or alkyl (meth) acrylate monomers as monomers that serve as raw materials for vinyl monomer structural units (other vinyl monomers) Can be used. Examples of such other vinyl monomers include monofunctional monomers such as acrylonitrile and alkyl methacrylate; divinylbenzene, ethylene glycol dimethacrylate, butylene glycol diacrylate, triallyl cyanurate, triallyl isocyanurate, Examples thereof include polyfunctional monomers such as methylolpropane triacrylate and pentaerythritol tetraacrylate. These may be used alone or in combination of two or more.

The polymerization method for producing rubber latex (latex containing rubber particles) as a raw material for the rubber graft polymer is not particularly limited, and examples thereof include emulsion polymerization and suspension polymerization in aqueous systems and solution polymerization in solution systems. Emulsion polymerization is preferred in terms of controlling the particle size of rubber particles and easily obtaining rubber particles having a core / shell structure.
The polymerization initiator used for the polymerization is not particularly limited, and for example, an azo initiator or a peroxide initiator can be used. These may be used alone or in combination of two or more. The amount of the polymerization initiator used is preferably 0.05 to 1.0 part by mass and more preferably 0.1 to 0.3 part by mass with respect to 100 parts by mass in total of the monomers.

As the emulsifier used in the emulsion polymerization, an emulsifier that is a salt of a weak acid and a strong base or a nonionic emulsifier is preferable.
When an emulsifier that is a salt of a strong acid and a strong base is used as an emulsifier for emulsion polymerization, a trace amount of the strong acid or salt derived from this emulsifier remains in the rubber graft polymer. When a rubbery graft polymer in which a trace amount of a strong acid or salt remains is blended with a polycarbonate resin, the polycarbonate resin is easily decomposed by strongly acidic ions released from the strong acid or salt. As a result, the heat resistant colorability of the molded product is lowered, or the flame retardancy is lowered.
In particular, when the rubber part of the rubber-like graft polymer contains a diene structural unit, the rubber part (for example, butadiene rubber or the like) is likely to be oxidized and deteriorated by the liberated strong acidic ions. As a result, the heat resistant colorability of the molded product is lowered.
In the case of emulsion polymerization of rubber particles as a raw material of the rubber graft polymer, if an emulsifier which is a salt of a weak acid and a strong base or a nonionic emulsifier is used as an emulsifier, sulfate ions and sulfite ions contained in the water are used. A rubbery graft polymer having a total amount of 3.5 ppm or less and a chlorine ion content of 150 ppm or less is easily obtained.

Examples of emulsifiers that are salts of weak acids and strong bases include carboxylic acid-based emulsifiers and phosphoric acid-based emulsifiers. Carboxylic acid-based emulsifiers and phosphoric acid-based emulsifiers have low acidity when ions are liberated.
On the other hand, nonionic emulsifiers do not generate ions.
The sulfonic acid-based emulsifier is preferably not used when the rubber particles are subjected to emulsion polymerization because the acidity is high when ions are liberated.

  Examples of the carboxylic acid-based emulsifier include caprylic acid, pelargonic acid, capric acid, lauric acid, myristic acid, palmitic acid, margaric acid, stearic acid, arachidic acid, behenic acid, lignoceric acid, serotic acid, montanic acid, myristoleic acid , Palmitoleic acid, oleic acid, elaidic acid, vaccenic acid, ricinoleic acid, gadoleic acid, eicosenoic acid, erucic acid, nervonic acid, linoleic acid, eicosadienoic acid, docosadienoic acid, linolenic acid, pinolenic acid, eleostearic acid, mead acid , Eicosatrienoic acid, stearidonic acid, arachidonic acid, eicosatetraenoic acid, adrenic acid, boseopentenoic acid, eicosapentaenoic acid, ozbond acid, sardine acid, tetracosapentaenoic acid, docosahexaenoic acid, nisic acid, etc. ~ 28 a Metal salts of oligo-carboxylic acid compounds such as alkenyl succinic acid; metal salts of saturated / unsaturated fatty acids having Kill group N- lauroyl sarcosine, and metal salts of sarcosine derivatives such as N- cocoyl sarcosine and the like. These may be used alone or in combination of two or more.

  Commercially available carboxylic acid emulsifiers include, for example, “Diprozin K-25” and “Neoscope SLN-100” manufactured by Toho Chemical Industry Co., Ltd .; “Nonsar TK-1” manufactured by Nippon Oil &Fats; “NS” manufactured by Kao Corporation "Soap", "SS-40N", "FR-14", "FR-25", "Latemul ASK" and the like.

  Examples of the phosphoric acid emulsifier include polyoxyethylene phenyl ether phosphoric acid, polyoxyethylene alkyl phenyl ether phosphoric acid, polyoxyethylene alkyl ether phosphoric acid, and alkyl phosphoric acid. These phosphoric acid-based emulsifiers may be in an acid form or a salt form such as a sodium salt or a potassium salt. These may be used alone or in combination of two or more.

  Examples of commercially available phosphoric acid emulsifiers include “Phosphanol ML-200”, “Phosphanol GF-199”, “Phosphanol RA-600”, and “Phosphanol RS-” manufactured by Toho Chemical Industries, Ltd. 610NA "," phosphanol SC-6103 "," phosphanol LP-700 "and the like.

  Nonionic emulsifiers include, for example, polyoxyalkylene alkyl ether, polyoxyethylene alkylene alkyl ether, polyoxyethylene distyrenated phenyl ether, polyoxyethylene tribenzyl phenyl ether, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene Examples thereof include oxyethylene fatty acid esters.

  Examples of commercially available nonionic emulsifiers include “Emulgen 120”, “Emulgen LS-114”, “Emulgen A-90”, “Leodol SP-L10”, “Leodol TW-L120”, “Emanon” manufactured by Kao Corporation. 1112 "or the like.

  Said carboxylic acid type emulsifier, phosphoric acid type emulsifier and nonionic emulsifier may be used independently and may use 2 or more types together. Further, as will be described in detail later, among the above-mentioned emulsifiers, at least one emulsifier selected from carboxylic acid emulsifiers and phosphoric acid emulsifiers is used in order to facilitate coagulation when recovering the rubbery graft polymer. Is preferably used.

  Although the usage-amount of an emulsifier is not specifically limited, 0.1-20.0 mass parts is preferable with respect to 100 mass parts of resin solid content in rubber latex, 0.1-15.0 mass parts is more preferable, 0.1-10.0 mass parts is further more preferable, 0.1-8.0 mass parts is especially preferable, and 1.5-8.0 mass parts is the most preferable. When the amount of the emulsifier used is 0.1 part by mass or more, the emulsion stability is excellent, and when it is 20.0 parts by mass or less, the latex of the rubber-like graft polymer is easily coagulated. Further, the smaller the amount of emulsifier used, the lower the total amount of sulfate ions and sulfite ions contained in the water and the content of chlorine ions in the rubber-like graft polymer.

The volume average particle diameter of the rubber particles in the rubber latex that is a raw material for the rubber graft polymer is preferably 0.1 to 1 μm, and more preferably 0.15 μm or more. The volume average particle diameter of the rubber particles in the rubber latex is more preferably 0.7 μm or less, and further preferably 0.5 μm or less. When the volume average particle diameter of the rubber particles in the rubber latex is 0.1 μm or more, the impact resistance at low temperature of the polycarbonate resin composition of the present invention in which the rubber-like graft polymer is added to the polycarbonate resin can be improved. it can. Further, when the volume average particle diameter of the rubber particles is 1 μm or less, cullet is hardly generated during the production of the rubber-like graft polymer.
Here, the “volume average particle diameter” of the rubber particles in the rubber latex means a 50% volume average particle diameter of the rubber particles in the rubber latex measured using a light scattering particle meter. The measuring method will be described later.

(Rubber particle enlargement)
The volume average particle diameter of the rubber particles in the rubber latex is about 0.1 μm according to ordinary emulsion polymerization. In order to adjust the volume average particle diameter to 0.1 to 1 μm, a method of enlarging rubber particles in the rubber latex with a thickening agent is used. The enlargement of the rubber particles can be performed by adding a thickening agent to the rubber latex. The thickening agent can be arbitrarily selected from known ones, but it is preferable to use an acid group-containing copolymer (K) and / or an oxyacid salt (M).

  The acid group-containing copolymer (K) is preferably a polymer obtained by polymerizing a monomer mixture containing an unsaturated acid, an alkyl acrylate, and, if necessary, other copolymerizable components.

  Examples of the unsaturated acid include acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, cinnamic acid, sorbic acid, and p-styrenesulfonic acid. Among these, acrylic acid and methacrylic acid are preferable from the viewpoint of availability and handleability. These may be used alone or in combination of two or more.

  Examples of the alkyl acrylate include methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, isopropyl acrylate, hexyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, and the like. Among these, alkyl acrylates having 1 to 12 carbon atoms in the alkyl group are preferable. These may be used alone or in combination of two or more.

  The other copolymerizable monomer is not particularly limited as long as it can be copolymerized with an unsaturated acid or alkyl acrylate, and examples thereof include styrene derivatives such as α-methylstyrene, alkyl methacrylate, acrylonitrile and the like. These may be used alone or in combination of two or more.

  The composition of the monomer mixture used for the production of the acid group-containing copolymer (K) is 3 to 40% by weight of unsaturated acid, 35 to 97% by weight of alkyl acrylate, and other copolymerizable monomers. Is preferably 0 to 40% by mass, unsaturated acid is 5 to 35% by mass, alkyl acrylate is 40 to 95% by mass, and other copolymerizable monomers are 0 to 35% by mass. More preferred. If the composition of the monomer mixture is within the above range, the stability of the latex during enlargement is excellent, and the rubber particle diameter of the rubber latex obtained by enlargement can be easily controlled.

  The acid group-containing copolymer (K) can be obtained by polymerizing the monomer mixture having the above composition by a known emulsion polymerization method. The polymerization may be performed in one stage or in multiple stages. By polymerizing in multiple stages, an acid group-containing copolymer (K) having a multilayer structure of two or more layers can be obtained.

When the rubber particles are enlarged, the oxyacid salt (M) can be used as long as the performance of the rubber-like graft polymer is not hindered.
The oxyacid salt (M) is preferably at least one oxyacid salt selected from alkali metal salts or alkaline earth metal salts of oxyacids, or zinc, nickel, and aluminum salts. Examples of such oxyacid salts (M) include salts of sulfuric acid, nitric acid, phosphoric acid and the like with potassium, sodium, magnesium, calcium, nickel, aluminum and the like. Oxygenate (M) is potassium sulfate, sodium sulfate, magnesium sulfate, aluminum sulfate, sodium phosphate in terms of ease of particle size control during enlargement, availability, and ease of handling. Magnesium phosphate and the like are preferable.

  These acid group-containing copolymers (K) and oxyacid salts (M) may be used alone or in combination of two or more. When each of the acid group-containing copolymer (K) and the oxyacid salt (M) is used alone, the addition amount of the acid group-containing copolymer (K) is 100 mass of resin solid content of rubber latex as the polymer solid content. 0.1-5 mass parts is preferable with respect to a part, 0.5-4 mass parts is more preferable, 0.5-3 mass parts is further more preferable. Moreover, 0.1-5 mass parts is preferable with respect to 100 mass parts of resin solid content of rubber latex, and, as for the addition amount of oxyacid salt (M), 0.1-4 mass parts is more preferable. By adding the acid group-containing copolymer (K) and the oxyacid salt (M) within these ranges, the rubber particles in the rubber latex are more efficiently enlarged, and the resulting enlarged rubber latex can be obtained. Stability is also greatly improved.

  In addition, when performing an enlargement process using an acid group containing copolymer (K), it is preferable that pH of rubber latex is 7 or more. When the pH is on the acidic side, the enlargement efficiency may be low even when the acid group-containing copolymer (K) is added. The pH of the rubber latex may be adjusted during the production of the rubber latex, or may be performed separately before the enlargement treatment.

(Process (b))
The rubber-like graft polymer latex is obtained, for example, by polymerizing a vinyl monomer component in the presence of a latex (rubber latex) containing rubber particles composed of a rubber portion. The vinyl monomer component polymerized in the presence of rubber latex is a graft monomer component, and is a single monomer selected from (meth) acrylate, aromatic vinyl monomer, and vinyl cyanide monomer. It preferably includes a body. At least a part of the graft monomer component is preferably grafted to the rubber part to form a graft polymer.

Although it does not specifically limit as (meth) acrylate for grafting, For example, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, i-propyl (meth) acrylate, n-butyl (meth) Examples include acrylate, i-butyl (meth) acrylate, t-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and the like. These may be used alone or in combination of two or more.
Examples of the aromatic vinyl monomer for grafting include styrene, α-methylstyrene, vinyltoluene, chlorostyrene and the like. These may be used alone or in combination of two or more.
Examples of the vinyl cyanide monomer for grafting include acrylonitrile and methacrylonitrile. These may be used alone or in combination of two or more.

  The graft part preferably contains a methyl methacrylate structural unit. The proportion of methyl methacrylate in 100% by mass of the vinyl monomer component for grafting is preferably from 0.1 to 99.9% by mass, and more preferably from 20 to 80% by mass. When the vinyl monomer component contains 0.1% by mass or more of methyl methacrylate, the rubber-like graft polymer can be uniformly dispersed in the polycarbonate resin.

  The ratio of the rubber particles in 100% by mass of the rubber graft polymer can be arbitrarily set, but is preferably 50 to 90% by mass. If this value is 50 mass% or more, it is preferable in terms of strength development. Moreover, if this value is 90 mass% or less, it is preferable from a viewpoint of the dispersibility to polycarbonate resin, coagulation | solidification of a rubber-like graft polymer, and collection | recovery.

  The method of graft polymerization of the vinyl monomer component onto the rubber latex is not particularly limited, but emulsion polymerization is preferred because the particle diameter is controlled and the core / shell structure can be easily formed. As the emulsion polymerization method, generally known emulsion polymerization methods such as batch addition polymerization of monomers, continuous addition polymerization of monomers, and multistage polymerization can be employed. The addition of the emulsifier can employ the same method as the addition of the monomer.

  The graft layer may be one layer or two or more layers. When a rubber having a butadiene structural unit is copolymerized with a vinyl monomer having high hydrophobicity and low polymerization, such as styrene, the butadiene rubber and styrene are copolymerized, and the rubber becomes hard or a rubber-like graft polymer. In some cases, the refractive index of the film tends to fluctuate. For this reason, in graft polymerization, a monomer having high hydrophilicity and high polymerizability and having a high glass transition temperature, for example, a monomer mainly composed of methyl methacrylate, is graft-polymerized, and then hydrophobic such as styrene. It is preferred to polymerize high vinyl monomers.

As the emulsifier used in the emulsion polymerization, an emulsifier that is a salt of a weak acid and a strong base or a nonionic emulsifier is preferable.
When an emulsifier that is a salt of a strong acid and a strong base is used as an emulsifier for emulsion polymerization, as described above, a strong acid or salt derived from this emulsifier is left in a trace amount in the rubber graft polymer, and is released. As a result, the polycarbonate resin is easily decomposed, and as a result, the heat-resistant coloring property of the molded product is lowered or the flame retardancy is lowered. In particular, when the rubber part of the rubber-like graft polymer contains a diene structural unit, the rubber part (for example, butadiene rubber or the like) is likely to be oxidized and deteriorated by the liberated strong acidic ions. As a result, the heat resistant colorability of the molded product is lowered.
When graft polymerization is carried out by emulsion polymerization, if an emulsifier that is a salt of a weak acid and a strong base or a nonionic emulsifier is used as the emulsifier, the total amount of sulfate ions and sulfite ions contained in the water is 3.5 ppm or less. Thus, a rubbery graft polymer having a chlorine ion content of 150 ppm or less is easily obtained.
Examples of emulsifiers that are salts of weak acids and strong bases and nonionic emulsifiers include the carboxylic acid-based emulsifiers, phosphoric acid-based emulsifiers, and nonionic emulsifiers exemplified above in the description of the rubber part.

  Although the usage-amount of an emulsifier is not specifically limited, 0.05-3 mass parts is preferable with respect to 100 mass parts of vinyl monomer components, and 0.1-2 mass parts is more preferable. Further, the smaller the amount of emulsifier used, the lower the total amount of sulfate ions and sulfite ions contained in the water and the content of chlorine ions in the rubber-like graft polymer.

  The polymerization initiator used for the polymerization of the rubber graft polymer latex can be the same as the polymerization initiator used to polymerize the rubber latex, and the amount used is 100 parts by mass of the vinyl monomer component. 0.05-1.0 mass part is preferable and 0.1-0.3 mass part is more preferable.

(Process (c))
The rubber-like graft polymer can be obtained by spray recovery from the rubber-like graft polymer latex obtained as described above, or by coagulating and collecting the rubber-like graft polymer latex. In the present invention, the rubber graft polymer latex used for obtaining the powder may be used alone or in combination of two or more.

  The rubber graft polymer latex was coagulated by, for example, bringing the rubber graft polymer latex into contact with hot water in which the coagulant was dissolved, and coagulating the polymer with stirring to form a slurry. Examples include a method of dehydrating, washing, and drying the precipitate.

If the coagulant used to coagulate the rubber graft polymer latex is a strong acid or a salt of a strong acid and a strong base, a trace amount of strong acid or salt derived from the coagulant remains in the resulting rubber graft polymer. However, the polycarbonate resin tends to be decomposed by strongly acidic ions released from the strong acid or salt. As a result, the heat resistant colorability of the molded product is lowered, or the flame retardancy is lowered. In particular, when the rubber part of the rubber-like graft polymer contains a diene structural unit, the rubber part (for example, butadiene rubber or the like) is likely to be oxidized and deteriorated by the liberated strong acidic ions. As a result, the heat resistant colorability of the molded product is lowered.
Therefore, as the coagulant, a salt of a weak acid and a strong base is preferably used, and an alkali (earth) metal salt of a weak acid is more preferably used. When a salt of a weak acid and a strong base is used as a coagulant, the total amount of sulfate ions and sulfite ions contained in the water is 3.5 ppm or less, and the content of the rubber-like graft weight is 150 ppm or less. Coalescence is easily obtained.

Examples of the coagulant that is a salt of a weak acid and a strong base include alkali (earth) metal salts of organic acids such as sodium acetate, potassium acetate, calcium acetate, magnesium acetate, and barium acetate; sodium phosphate and potassium phosphate And alkali (earth) metal salts of inorganic acids other than sulfuric acid such as calcium phosphate. These may be used alone or in combination of two or more.
Since these coagulants are used as aqueous solutions, it is preferable that they have high water solubility. The coagulant is preferably one that forms a hardly dissociable salt with the emulsifier contained in the rubber graft polymer latex during coagulation. Even if such a coagulant remains in a small amount in the rubber-like graft polymer, it is difficult to reduce the thermal stability of the polycarbonate resin composition obtained by blending the polymer with the polycarbonate resin.
From these viewpoints, among the coagulants, alkaline earth metal salts of organic acids or alkaline earth metal salts of inorganic acids other than sulfuric acid are preferable, among which calcium salts and magnesium salts are more preferable, and calcium acetate is more preferable. .

  The amount of the coagulant used for coagulating the rubber graft polymer latex is not particularly limited as long as the latex is sufficiently coagulated, but the resin solid content in the rubber graft polymer latex is 100 parts by mass. Is preferably 0.1 to 20 parts by mass, more preferably 0.1 to 12 parts by mass, still more preferably 0.5 to 10 parts by mass, and particularly preferably 0.5 to 8 parts by mass. When the amount of the coagulant used is 0.1 parts by mass or more, the powder-recoverability and powder-handling property of the rubber-like graft polymer are good. On the other hand, when the amount of the coagulant used is 20 parts by mass or less, the polycarbonate resin composition obtained by blending the obtained rubber-like graft polymer into the polycarbonate resin has good thermal stability. Further, as the amount of the coagulant used is smaller, the total amount of sulfate ions and sulfite ions contained in the water and the content of chlorine ions in the rubber graft polymer can be reduced.

  The method for washing the coagulated material obtained by the coagulation recovery method is not particularly limited, but water or an alcohol having 4 or less carbon atoms such as methanol, ethanol, isopropyl alcohol, etc., is used in order to increase the washing efficiency. It is preferable to wash with water, and particularly with water and / or methanol.

Recovery of the rubbery graft polymer from the rubbery graft polymer latex may be performed by spray recovery instead of coagulation. This is because spray recovery does not require the use of a strong acid or a salt of a strong acid and a strong base as a coagulant. However, as a method for recovering the rubbery graft polymer, a coagulation recovery method using a coagulant that is a salt of a weak acid and a strong base is preferable to the spray recovery method. This is because the coagulation recovery includes a washing step, so that the amount of ions remaining in the rubber can be further reduced.
Here, “spray recovery” refers to recovering the rubber graft polymer by spraying latex containing the rubber graft polymer into fine droplets and then drying it by applying hot air.

  Examples of the method for spraying rubber graft polymer latex into the spray recovery device in the form of fine droplets include a rotating disk type, a pressure nozzle type, a two-fluid nozzle type, and a pressurized two-fluid nozzle type. It is done. As a capacity | capacitance of a spray collection | recovery apparatus, any from the small capacity | capacitance used in a laboratory to the large capacity | capacitance used industrially may be sufficient. What is necessary is just to select suitably the structure of the supply part of the heating gas for drying in a spray collection | recovery apparatus, and the structure of the discharge part of the heating gas for drying and dry powder according to the objective. The temperature of the heating gas for drying is preferably 200 ° C. or less, and more preferably 120 to 180 ° C.

  Further, in order to improve powder characteristics such as prevention of powder blocking at the time of spray recovery and an increase in bulk specific gravity, inorganic particles such as silica may be added to the rubber-like graft polymer latex for spray recovery. .

<< Antioxidant >>
One or two or more kinds of commonly known antioxidants can be added to the rubbery graft polymer for the purpose of antioxidant. The method of adding the antioxidant to the rubber graft polymer is not particularly limited, but it is added as a powder or tablet having a particle size of several hundred μm, or in a state dispersed in water (a dispersion). The method of doing is mentioned. In the present invention, a method of adding an antioxidant to the rubber graft polymer latex by dispersion is most preferable, and the above-mentioned coagulation or spray recovery of the rubber graft polymer latex to which the antioxidant is added is performed. Thus, a rubbery graft polymer to which an antioxidant is added is obtained. By adding the antioxidant in a dispersion, the antioxidant can be added more uniformly, close to the rubber-like graft polymer, so that oxidative degradation of rubber parts such as butadiene rubber is suppressed, and it is more excellent Heat resistant colorability is obtained.

  The addition amount of the antioxidant is preferably 0.0001 to 10 parts by mass with respect to 100 parts by mass of the rubbery graft polymer, and the lower limit is more preferably 0.001 parts by mass or more, and 0.01 parts by mass or more. More preferably, the upper limit is more preferably 6 parts by mass or less, and still more preferably 3 parts by mass or less. There exists a tendency for the inhibitory effect of the coloring at the time of shaping | molding to become favorable that the addition amount of antioxidant is more than the said lower limit. On the other hand, when the content of the antioxidant is not more than the above upper limit value, a product having a good surface appearance can be obtained by suppressing the deposits on the mold during injection molding.

  The antioxidant is preferably at least one selected from the group consisting of phenolic antioxidants, thioether antioxidants, and phosphate antioxidants, phenolic antioxidants and / or thioethers. Antioxidants are more preferred.

Examples of the phenolic antioxidant include pentaerythritol tetrakis (3-mercaptopropionate), pentaerythritol tetrakis (3-laurylthiopropionate), glycerol-3-stearylthiopropionate, triethylene glycol-bis [ 3- (3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate], 1,6-hexanediol-bis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] , Pentaerythritol-tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, 1 , 3,5-trimethyl-2 4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene, N, N-hexamethylenebis (3,5-di-tert-butyl-4-hydroxy-hydrocinnamide), 3,5-di-tert-butyl-4-hydroxy-benzylphosphonate-diethyl ester, tris (3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate, 4,4′-biphenylenediphosphinic acid tetrakis ( 2,4-di-tert-butylphenyl), 3,9-bis {1,1-dimethyl-2- [β- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy] ethyl} -2,4,8,10-tetraoxaspiro (5,5) undecane and the like.
Among these compounds, an aromatic monohydroxy compound substituted with one or more alkyl groups having 5 or more carbon atoms is preferable, and specific octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) is preferable. Propionate, pentaerythritol-tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], 1,6-hexanediol-bis [3- (3,5-di-tert-butyl- 4-hydroxyphenyl) propionate], 1,3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene and the like. Among these, pentaerythritol-tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] is particularly preferable.

  Examples of the thioether-based antioxidant include dilauryl-3,3′-thiodipropionic acid ester, ditridecyl-3,3′-thiodipropionic acid ester, dimyristyl-3,3′-thiodipropionic acid ester, and distearyl. −3,3′-thiodipropionic acid ester, lauryl stearyl-3,3′-thiodipropionic acid ester, pentaerythritol tetrakis (3-laurylthiopropionate), bis [2-methyl-4- (3- Laurylthiopropionyloxy) -5-tert-butylphenyl] sulfide, octadecyl disulfide, mercaptobenzimidazole, 2-mercapto-6-methylbenzimidazole, 1,1′-thiobis (2-naphthol) (bis [3- (dodecylthio) ) Propionic acid] 2,2-bis [3- (dodecylthio) -1-oxopropyl] methyl] -1,3-propanediyl), and the like. Among these, (bis [3- (dodecylthio) propionic acid] 2,2-bis [[3- (dodecylthio) -1-oxopropyloxy] methyl] -1,3-propanediyl) is preferable.

  As the thioether-based antioxidant, those having a molecular weight of 700 or more are preferable. If the molecular weight is 700 or more, it has low volatility, and thus exhibits superior heat resistant colorability even during high temperature molding of the polycarbonate resin composition.

  Examples of phosphate antioxidants include triphenyl phosphite, trisnonylphenyl phosphite, tris (2,4-di-tert-butylphenyl) phosphite, tridecyl phosphite, trioctyl phosphite, and trioctadecyl phosphite. Didecyl monophenyl phosphite, dioctyl monophenyl phosphite, diisopropyl monophenyl phosphite, monobutyl diphenyl phosphite, monodecyl diphenyl phosphite, monooctyl diphenyl phosphite, bis (2,6-di-tert-butyl- 4-methylphenyl) pentaerythritol diphosphite, 2,2-methylenebis (4,6-di-tert-butylphenyl) octyl phosphite, bis (nonylphenyl) pentaerythritol Diphosphite, bis (2,4-di -tert- butylphenyl) pentaerythritol diphosphite, and distearyl pentaerythritol phosphite. Among these, trisnonylphenyl phosphite, triphenyl phosphite, tris (2,4-di-tert-butylphenyl) phosphite, bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite, Bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite is preferred, and tris (2,4-di-tert-butylphenyl) phosphite is more preferred.

<< Content >>
0.1-30 mass parts is preferable with respect to 100 mass parts of polycarbonate resin, as for content of a rubber-like graft polymer, 0.5 mass part or more is more preferable, and 1 mass part or more is further more preferable. Further, the content of the rubber-like graft polymer is more preferably 20 parts by mass or less, further preferably 15 parts by mass or less, particularly preferably 12.5 parts by mass or less, relative to 100 parts by mass of the polycarbonate resin. The following are most preferred. If the content of the rubber-like graft polymer is not less than the above lower limit value, the impact strength of the molded product is further increased and the molded product is hardly broken. On the other hand, if the content of the rubber-like graft polymer is not more than the above upper limit value, good moldability can be obtained, and it is possible to suppress the occurrence of resin burn or the loss of color developability during molding.

<Other ingredients>
The polycarbonate resin composition may contain other thermoplastic resins other than the polycarbonate (PC) resin, and additives such as an antioxidant and a mold release agent, as long as the effects of the present invention are not impaired.
As the other thermoplastic resins, almost all known thermoplastic resins can be used. Specific examples of other thermoplastic resins include olefin resins such as polypropylene (PP) and polyethylene (PE), polystyrene (PS), high impact polystyrene (HIPS), (meth) acrylic acid ester / styrene copolymer ( MS), styrene / acrylonitrile copolymer (SAN), styrene / maleic anhydride copolymer (SMA), acrylonitrile / butadiene / styrene copolymer (ABS), acrylonitrile / styrene / acrylate copolymer (ASA), acrylonitrile・ Styrene resins (St resin) such as ethylene propylene / styrene copolymer (AES), acrylic resins (Ac resin) such as polymethyl methacrylate (PMMA), polyamide resin (PA resin), polyethylene Terephthalate (PET), polyb Polyester resins (PEs resins) such as terephthalate (PBT), (modified) polyphenylene ether resins (PPE resins), polyoxymethylene resins (POM resins), polysulfone resins (PSO resins), Engineering plastics such as polyarylate resin (PAr resin), polyphenylene resin (PPS resin), thermoplastic polyurethane resin (PU resin), styrene elastomer, olefin elastomer, vinyl chloride elastomer, urethane Elastomers, polyester elastomers, polyamide elastomers, fluorine elastomers, 1,2-polybutadiene, thermoplastic elastomers (TPE) such as trans 1,4-polyisoprene, PC resins such as PC / ABS / St resin alloys PVC resin such as polyvinyl chloride (PVC) / ABS / St resin alloy, PA resin such as PA / ABS / St resin alloy, PA resin / TPE alloy, PA resin such as PA / PP / polyolefin -Based resin alloy, PBT-based resin / TPE, PC-based resin such as PC / PBT / PEs-based resin alloy, polyolefin-based resin / TPE, alloy between olefin-based resins such as PP / PE, PPE / HIPS, PPE / PBT, Examples thereof include polymer alloys such as PPE resin alloys such as PPE / PA, PVC resins such as PVC / PMMA / Ac resin alloys, and hard, semi-rigid and soft vinyl chloride resins. These may be used alone or in combination of two or more. Furthermore, a compatibilizing agent such as a graft copolymer can be used in combination.

  Examples of the additive include an antioxidant, a release agent, an ultraviolet absorber / light stabilizer, and a bluing agent.

(Antioxidant)
As described above, the antioxidant may be added to the rubber graft polymer latex during the production of the rubber graft polymer, or may be blended with polycarbonate resin, flame retardant, polytetrafluoroethylene, rubber graft. When mixing a polymer and manufacturing a polycarbonate resin composition, you may mix | blend by adding to these.

The antioxidant is preferably at least one selected from the group consisting of phenolic antioxidants, phosphate antioxidants, and sulfur antioxidants, phenolic antioxidants and / or phosphates. Antioxidants are more preferred.
Examples of the phenol-based antioxidant and the phosphate-based antioxidant include the phenol-based antioxidant and the phosphate-based antioxidant exemplified above in the description of the rubbery graft polymer, and the same as preferable antioxidants. Can be mentioned.

  Examples of the sulfur-based antioxidant include dilauryl-3,3′-thiodipropionic acid ester, ditridecyl-3,3′-thiodipropionic acid ester, dimyristyl-3,3′-thiodipropionic acid ester, and distearyl. −3,3′-thiodipropionic acid ester, lauryl stearyl-3,3′-thiodipropionic acid ester, pentaerythritol tetrakis (3-laurylthiopropionate), bis [2-methyl-4- (3- Laurylthiopropionyloxy) -5-tert-butylphenyl] sulfide, octadecyl disulfide, mercaptobenzimidazole, 2-mercapto-6-methylbenzimidazole, 1,1′-thiobis (2-naphthol) and the like. Among these, pentaerythritol tetrakis (3-lauryl thiopropionate) is preferable.

  When adding an antioxidant when mixing the polycarbonate resin, flame retardant, polytetrafluoroethylene, and rubbery graft polymer, the added amount of the antioxidant is 0.0001 mass relative to 100 mass parts of the polycarbonate resin. Part or more, preferably 0.001 part by weight or more, more preferably 0.01 part by weight or more. Moreover, 1 mass part or less is preferable with respect to 100 mass parts of polycarbonate resin, and, as for the addition amount of antioxidant, 0.5 mass part or less is more preferable, and 0.3 mass part or less is further more preferable. If the addition amount of the antioxidant is equal to or greater than the above lower limit, the coloring suppression effect at the time of molding tends to be good, but if the content of the antioxidant is larger than the above upper limit value, it is attached to the mold at the time of injection molding. The surface appearance of the product may be impaired due to an increase in the amount of kimono or an increase in the amount of deposits on the roll when the film is formed by extrusion.

(Release agent)
The mold release agent is blended for the purpose of further improving the mold release from the cooling roll during sheet molding or the mold during injection molding.
Examples of the release agent include higher fatty acid esters of mono- or polyhydric alcohols, higher fatty acids, paraffin wax, beeswax, olefin wax, olefin wax containing carboxy group and / or carboxylic anhydride group, silicone oil, And organopolysiloxane. These may be used alone or in combination of two or more.

  The higher fatty acid ester is preferably a partial ester or a total ester of a monovalent or polyhydric alcohol having 1 to 20 carbon atoms and a saturated fatty acid having 10 to 30 carbon atoms. Examples of partial esters or total esters of monohydric or polyhydric alcohols and saturated fatty acids include stearic acid monoglyceride, stearic acid diglyceride, stearic acid triglyceride, stearic acid monosorbate, stearyl stearate, behenic acid monoglyceride, and behenyl behenate. , Pentaerythritol monostearate, pentaerythritol tetrastearate, pentaerythritol tetrapelargonate, propylene glycol monostearate, stearyl stearate, palmityl palmitate, butyl stearate, methyl laurate, isopropyl palmitate, biphenyl biphene And sorbitan monostearate, 2-ethylhexyl stearate and the like. Among these, stearic acid monoglyceride, stearic acid triglyceride, pentaerythritol tetrastearate, and behenyl behenate are preferable. A stearic acid ester is more preferable as a mold release agent from the viewpoints of mold release and transparency.

  As the stearic acid ester, a partial or total ester of a substituted or unsubstituted monovalent or polyhydric alcohol having 1 to 20 carbon atoms and stearic acid is preferable. Examples of the partial ester or total ester of monohydric or polyhydric alcohol and stearic acid include ethylene glycol distearate, stearic acid monoglyceride, stearic acid diglyceride, stearic acid triglyceride, stearic acid monosorbate, stearyl stearate, penta Examples include erythritol monostearate, pentaerythritol tetrastearate, propylene glycol monostearate, stearyl stearate, butyl stearate, sorbitan monostearate, 2-ethylhexyl stearate and the like. Among these, stearic acid monoglyceride, stearic acid triglyceride, pentaerythritol tetrastearate and stearyl stearate are more preferable, and ethylene glycol distearate and stearic acid monoglyceride are more preferable.

  As the higher fatty acid, a substituted or unsubstituted saturated fatty acid having 10 to 30 carbon atoms is preferable, and an unsubstituted saturated fatty acid having 10 to 30 carbon atoms is more preferable. Examples of such higher fatty acids include myristic acid, lauric acid, palmitic acid, stearic acid, and behenic acid. Among these, saturated fatty acids having 16 to 18 carbon atoms are preferable. Examples of such saturated fatty acids include palmitic acid and stearic acid, and stearic acid is particularly preferable.

  The amount of the release agent added is preferably 0.001 part by mass or more, more preferably 0.01 part by mass or more, and further preferably 0.1 part by mass or more with respect to 100 parts by mass of the polycarbonate resin. Further, the amount of the release agent added is preferably 2 parts by mass or less, more preferably 1 part by mass or less, and further preferably 0.5 parts by mass or less with respect to 100 parts by mass of the polycarbonate resin. If the content of the release agent is excessively large, deposits on the mold may increase at the time of molding, and if a large amount of molding is performed, there is a possibility that labor may be required for mold maintenance. Moreover, there is a possibility that the resulting molded product may have a poor appearance. If the content of the release agent in the polycarbonate resin composition is not less than the above lower limit value, there is an advantage that the molded product can be easily released from the mold at the time of molding, and the molded product can be easily obtained.

(UV absorber / light stabilizer)
The discoloration of the polycarbonate resin composition of the present invention by ultraviolet rays is remarkably small as compared with the conventional polycarbonate resin composition, but contains one or more of ultraviolet absorbers and light stabilizers for the purpose of further improvement. May be.
The ultraviolet absorber / light stabilizer is not particularly limited as long as it is a compound having ultraviolet absorbing ability. Examples of the compound having ultraviolet absorbing ability include organic compounds and inorganic compounds. Among these, an organic compound is preferable because it is easy to ensure affinity with the polycarbonate resin and is easily dispersed uniformly.

  The molecular weight of the organic compound having ultraviolet absorbing ability is not particularly limited, but is preferably 200 or more, more preferably 250 or more, preferably 600 or less, more preferably 450 or less, and further preferably 400 or less. If the molecular weight is too small, there is a possibility of causing a decrease in UV resistance performance after long-term use. When the molecular weight is excessively large, there is a possibility that the transparency of the resin composition is lowered after long-term use.

  Examples of the compound having ultraviolet absorbing ability include benzotriazole compounds, benzophenone compounds, malonic acid ester compounds, triazine compounds, benzoate compounds, salicylic acid phenyl ester compounds, cyanoacrylate compounds, oxalic acid anilide compounds, and the like. Is mentioned. Among these, benzotriazole compounds, hydroxybenzophenone compounds, and malonic ester compounds are preferable. These may be used alone or in combination of two or more.

  More specific examples of the benzotriazole compounds include 2- (2′-hydroxy-3′-methyl-5′-hexylphenyl) benzotriazole, 2- (2′-hydroxy-3′-t-butyl- 5'-hexylphenyl) benzotriazole, 2- (2'-hydroxy-3 ', 5'-di-t-butylphenyl) benzotriazole, 2- (2'-hydroxy-3'-methyl-5'-t -Octylphenyl) benzotriazole, 2- (2'-hydroxy-5'-t-dodecylphenyl) benzotriazole, 2- (2'-hydroxy-3'-methyl-5'-t-dodecylphenyl) benzotriazole, 2- (2′-hydroxy-5′-t-butylphenyl) benzotriazole, methyl-3- (3- (2H-benzotriazol-2-yl ) -5-t-butyl-4-hydroxyphenyl) propionate and the like.

  Examples of the benzophenone compounds include hydroxybenzophenone compounds such as 2,2'-dihydroxybenzophenone, 2,2 ', 4,4'-tetrahydroxybenzophenone and 2-hydroxy-4-octoxybenzophenone.

  Examples of the malonic ester compounds include 2- (1-arylalkylidene) malonic esters, tetraethyl-2,2 '-(1,4-phenylene-dimethylidene) -bismalonate, and the like.

  Examples of the triazine compound include 2- [4-[(2-hydroxy-3-dodecyloxypropyl) oxy] -2-hydroxyphenyl] -4,6-bis (2,4-dimethylphenyl) -1,3. , 5-triazine, 2,4-bis (2,4-dimethylphenyl) -6- (2-hydroxy-4-isooctyloxyphenyl) -s-triazine, 2- (4,6-diphenyl-1,3 , 5-triazin-2-yl) -5-[(hexyl) oxy] -phenol (manufactured by Ciba Geigy Japan, "Tinuvin 1577FF").

  Examples of the cyanoacrylate compound include ethyl-2-cyano-3,3-diphenyl acrylate, 2'-ethylhexyl-2-cyano-3,3-diphenyl acrylate, and the like.

  Examples of the oxalic acid anilide compound include 2-ethyl-2'-ethoxy-oxalanilide (manufactured by Clariant, Sanduvor VSU).

  The total addition amount of the ultraviolet absorber and the light stabilizer can be appropriately selected according to the kind of the ultraviolet absorber and the light stabilizer, but is 0.001 to 5 in 100% by mass of the polycarbonate resin composition. % By mass is preferable, and 0.01 to 2 parts by mass is preferable with respect to 100 parts by mass of the polycarbonate resin.

(Bluing agent)
The bluing agent is blended for the purpose of counteracting the yellowness of the molded product.
As the bluing agent, any bluing agent that can be used in conventional polycarbonate resins can be used without any problem. In general, anthraquinone dyes are easily available and preferred.

  Specific examples of the bluing agent include the general name Solvent Violet 13 [CA. No. (Color Index No.) 60725], generic name Solvent Violet 31 [CA. No. 68210], generic name Solvent Violet 33 [CA. No. 60725], generic name Solvent Blue 94 [CA. No. 61500], generic name Solvent Violet 36 [CA. No. 68210], generic name Solvent Blue97 [manufactured by Bayer "Macrolex Violet RR"], generic name Solvent Blue45 [CA. No. 61110].

The addition amount of the bluing agent is preferably 0.1 × 10 ⁻⁴ to 2 × 10 ⁻⁴ parts by mass with respect to 100 parts by mass of the polycarbonate resin.

(Other additives)
In addition to the above-mentioned additives, the polycarbonate resin composition can be used in various known additives such as a flame retardant aid, a hydrolysis inhibitor, an antistatic agent, a foaming agent, a dye, and the like as long as the effects of the present invention are not impaired. A pigment or the like can be contained. The polycarbonate resin composition may contain, for example, a synthetic resin such as aromatic polyester or amorphous polyolefin, or a biodegradable resin such as polylactic acid or polybutylene succinate.

<Production method of polycarbonate resin composition>
The polycarbonate resin composition can be produced by mixing a polycarbonate resin, a flame retardant, polytetrafluoroethylene, and a rubbery graft polymer. Specifically, for example, a pellet-like polycarbonate resin, a flame retardant, polytetrafluoroethylene, and a rubber-like graft polymer are mixed using an extruder, extruded into a strand, and pelletized with a rotary cutter or the like. A polycarbonate resin composition can be obtained by cutting into two.

  Moreover, when a polycarbonate resin composition contains another component, as a blending method of the other component, any method may be used as long as it is a commonly used blending method. For example, a method of mixing and kneading with a tumbler, V-type blender, super mixer, nauter mixer, Banbury mixer, kneading roll, extruder, etc., or a solution mixed in a common good solvent such as methylene chloride Although the blending method etc. are mentioned, this is not specifically limited.

  The polycarbonate resin composition of the present invention thus obtained is further added with various additives as required, and once formed into pellets directly or by a melt extruder, an extrusion molding method, an injection molding method, a compression molding method. It can be formed into a desired shape by a generally known forming method such as a method.

<Effect>
The polycarbonate resin composition of the present invention described above contains a polycarbonate resin, a flame retardant, polytetrafluoroethylene, and the specific rubbery graft polymer described above. A molded article having excellent impact properties can be obtained, and the corrosiveness to metals is low.

"Molding"
The molded article of the present invention is obtained by molding the above-described polycarbonate resin composition of the present invention. Although it does not restrict | limit especially as a shaping | molding method, For example, injection molding is mentioned. With injection molding, a molded product having a complicated shape can be obtained. If it is molded into a complicated shape, stress concentration portions tend to be generated. However, if the polycarbonate resin composition of the present invention is used, an impact strength improvement effect can be obtained, and therefore breakage due to stress concentration can be suppressed. .

  The molded article may be formed into a film or sheet by an extrusion molding method or the like of the polycarbonate resin composition of the present invention, or may be a plate molded by an injection molding method or an extrusion molding method. .

<Effect>
Since the molded article of the present invention described above is formed by molding the polycarbonate resin composition of the present invention, it is excellent in heat-resistant coloring, flame retardancy, and impact resistance.

Hereinafter, the present invention will be described in more detail with reference to examples.
Various measurement / evaluation methods are as follows.

"Measurement and evaluation methods"
(1) Measurement of volume average particle diameter of rubber particles in rubber latex Rubber latex is diluted with deionized water, and rubber diffraction scattering type particle size distribution meter (manufactured by Shimadzu Corporation, trade name: SALD-7100) is used to rubber. The volume average particle diameter of the particles was measured. The volume average particle diameter was calculated with the refractive index of the rubber particles set to 1.50.

(2) Measurement of the volume average particle diameter of the rubber-like graft polymer The latex of the rubber-like graft polymer is diluted with deionized water, and a laser diffraction scattering type particle size distribution analyzer (trade name; SALD-7100, manufactured by Shimadzu Corporation). Was used to measure the volume average particle diameter of the rubber graft polymer. The volume average particle size was calculated by setting the refractive index of the rubbery graft polymer to 1.50.

(3) Measurement of sulfate ion and sulfite ion content in rubbery graft polymer Weigh 20.0 g of rubbery graft polymer into a pressure vessel made of glass, add 200 ml of deionized water to this, And extraction with hot water at 95 ° C. for 20 hours. The solution was cooled to room temperature (25 ° C.) and then filtered through a cellulose mixed ester membrane filter having an opening of 0.2 μm, and the filtrate was used as a sample solution.
The amount of sulfate ion (SO ₄ ²⁻ ) and sulfite ion (SO ₃ ²⁻ ) in the sample solution using an ion chromatograph (manufactured by Nippon Dionex, trade name: IC-20 type, separation column: IonPac AS12A) Was measured. The calibration curve is a standard solution of sodium sulfate (manufactured by Kishida Chemical Co., Ltd., sulfate ion standard solution for ion chromatography (SO ₄ ²⁻ ): 1000 mg / L) and a standard solution of sodium sulfite (manufactured by Kishida Chemical Co., Ltd., sulfurous acid for ion chromatography). An ion standard solution (SO ₃ ²⁻ ): 1000 mg / L) was used, and SO ₄ ²⁻ and SO ₃ ²⁻ : prepared at one point of 20 ppm each. From the concentration determined by ion chromatography, the total amount (g / g) of the sulfate ion amount and sulfite ion amount contained in the rubber graft polymer was calculated.

(4) Measurement of chlorine ion content in rubber-like graft polymer 0.05 g of rubber-like graft polymer was completely burned with a sample combustion device (trade name: QF-02, manufactured by Mitsubishi Chemical Corporation), and the generated gas was discharged. The sample solution was absorbed in 20 ml of 0.3% hydrogen peroxide solution. The amount of chlorine (Cl ⁻ ) in the sample solution was measured using an ion chromatograph (manufactured by Nippon Dionex, trade name: IC-20 type, separation column: IonPac AS12A). A calibration curve was prepared by using a chloride ion standard solution for ion chromatography (Cl ⁻ ): 1000 mg / L, manufactured by Kishida Chemical Co., Ltd., and Cl ⁻ : 20 ppm at one point. The chlorine content (g / g) contained in the rubbery graft polymer was calculated from the concentration determined by ion chromatography.

(5) Evaluation of metal corrosion resistance 10 g of rubber-like graft polymer powder was weighed into a heat-resistant glass container, 10 g of deionized water was added thereto, and a clip made of alloy tool steel was further added. After holding for 10 days at normal temperature (23 ° C.), the corrosion state of the clip made of alloy tool steel was visually confirmed, and the metal corrosion resistance was evaluated according to the following evaluation criteria. The polycarbonate resin composition containing the rubbery graft polymer having an evaluation of “a” means that the corrosiveness to metal is low, that is, the metal corrosion resistance is excellent.
a: No corrosion.
c: Corrosion is present (rust is present).

(6) Preparation method of pellet and test piece 92.5 parts by mass of polycarbonate resin, 4.0 parts by mass of flame retardant, 0.5 parts by mass of polytetrafluoroethylene, and 3.0 parts by mass of rubber-like graft polymer Were mixed with a devolatilizing extruder (trade name; PCM-30, manufactured by Ikegai Co., Ltd.) heated to a barrel temperature of 280 ° C. under a screw rotation speed of 150 rpm to obtain a pellet-shaped polycarbonate resin composition. .
The obtained polycarbonate resin composition in the form of pellets was dried at 80 ° C. for 6 hours using a hot air dryer, and then a cylinder with a 100 t injection molding machine (manufactured by Sumitomo Heavy Industries, Ltd., trade name: SE-100DU). Molded under conditions of a temperature of 260 ° C. and a mold temperature of 70 ° C., a flat test piece 1 (length 100 mm, width 50 mm, thickness 2 mm), test piece 2 (length 80 mm, width 10 mm, thickness 4 mm), A test piece 3 (length 120 mm, width 12.7 mm, thickness 1.6 mm) was obtained.

(7) Evaluation of heat-resistant coloring property The YI value of the test piece 1 conforms to JIS K7105, and using a spectrocolor difference meter (manufactured by Nippon Denshoku Industries Co., Ltd., model name “SE2000”), conditions for a C light source and a two-degree field of view And measured by the reflected light measurement method.
First, heat aging the test piece before the first YI value (YI _B) was measured. Next, the test piece 1 was heat-aged at a temperature of 100 ° C. for 48 hours using a high-temp oven (manufactured by Tabaispec, model name “PMS-B”). Measured YI value of the test piece 1 after heat aging (YI _A), was calculated ΔYI value by the following equation.
ΔYI ₌ YI A -YI _B

(8) Evaluation of impact resistance Notched Charpy impact strength was measured using test piece 2 in accordance with JIS K7111, at measurement temperatures of -30 ° C and 23 ° C.

(9) Evaluation of flame retardancy According to the method of UL-94V, a flame retardance test was performed using five test pieces 3. The determination of flame retardancy was classified into V-0, V-1, V-2, and HB according to the evaluation method described in UL-94V (V-0 indicates the highest flame retardancy). The total combustion time is the total combustion time of five tubes (including the combustion time at the time of the first flame contact and the second flame contact), and the unit is indicated by “second”.

"material"
Table 1 shows the abbreviations of the compounds used in the following Examples and Comparative Examples.

"Manufacture of rubbery graft polymer"
<Production Example 1>
(Manufacture of rubber latex (H-1))
6 types of materials shown in the column of component (1) in Table 2 were charged into an autoclave with a capacity of 70 L, and when the temperature was raised to 43 ° C., 4 shown in the column of component (2) in Table 2 A redox initiator composed of various types of materials was added to the autoclave to initiate polymerization, and the temperature was further raised to 60 ° C. The reaction was carried out for 8 hours from the start of polymerization to obtain a latex (rubber latex (H-1)) containing butadiene rubber particles. The volume average particle diameter of the butadiene rubber particles in the obtained rubber latex (H-1) was 90 nm.

(Production of acid group-containing copolymer latex (K-1))
After charging six kinds of materials shown in the column of component (3) in Table 3 into the reaction vessel and raising the internal temperature to 60 ° C., three kinds of materials shown in the column of component (4) in Table 3 The mixture consisting of was polymerized by dropping continuously over 2 hours. By further stirring for 2 hours, an acid group-containing copolymer latex (K-1) having a monomer conversion of 97% or more was obtained.

(Manufacture of enlarged rubber latex (H-1 ′))
Of the produced rubber latex (H-1), 75 parts by mass of rubber latex (H-1) as a polymer solid is blended in a glass flask, and 2 parts by mass of acid groups as a polymer solid at an internal temperature of 50 ° C. The containing copolymer latex (K-1) was added and held for 30 minutes to enlarge the rubber particles in the rubber latex (H-1) to obtain an enlarged rubber latex (H-1 ′). The volume average particle diameter of the rubber particles in the resulting enlarged rubber latex (H-1 ′) was 200 nm.

(Production of rubber-like graft polymer (A-1))
Subsequently, in the reaction vessel containing the enlarged rubber latex (H-1 ′), three kinds of deionized water, sodium formaldehyde sulfoxylate, and potassium alkenyl succinate shown in the column of initial charge in Table 4 were prepared. The material was added and the temperature was raised to 65 ° C. Next, a mixture composed of three kinds of materials shown in the column of “first stage graft” in Table 4 was dropped over 25 minutes to allow polymerization to proceed, and then held for 40 minutes to perform the first graft polymerization step. .
Thereafter, in the presence of the polymer, a mixture composed of two kinds of materials shown in the column of “second stage graft” in Table 4 was dropped over 30 minutes, and then held for 1 hour, and the second graft polymerization step Went.
Thereafter, in the presence of the polymer, a mixture of two kinds of materials shown in the column of “3rd stage graft” in Table 4 was added dropwise over 10 minutes, and then held for 2 hours to obtain a third graft polymerization step. To obtain a rubber-like graft polymer latex.

  Irg1076 (n-octadecyl-3- (3 ′, 5′di-t-butyl-4′-hydroxyphenyl) propionate) 0.25 parts by mass of the phenolic antioxidant was obtained to the rubbery graft polymer latex obtained. And AO-412S (bis [3- (dodecylthio) propionic acid] 2,2-bis [[3- (dodecylthio) -1-oxopropyloxy] methyl] -1,3-propane, which is a thioether antioxidant 0.75 parts by mass of diyl) was added. This was added to 460 parts by mass of deionized water containing 5 parts by mass of calcium acetate to coagulate the polymer, washed with water, dehydrated, and dried to obtain a rubber graft polymer (A-1). Table 7 shows the types of antioxidants and coagulants and the amounts used.

<Production Examples 2-4, 6, 8>
Except having changed the kind and usage-amount of antioxidant, and the kind of coagulant into the conditions shown in Table 7, it is the same as that of manufacture example 1, rubbery graft polymer (A-2)-(A-4) ), (A′-1) and (A′-3) were obtained.

<Production Example 5>
Rubber graft as in Production Example 1 except that the emulsifier used for the production of rubber latex (H-1) was changed to 2.5 parts by weight of beef tallow fatty acid sodium (trade name: NS soap manufactured by Kao Corporation). A polymer latex was obtained.
The rubbery graft polymer (A-5) was used in the same manner as in Production Example 1 except that the obtained rubbery graft polymer latex was used and the type and amount of the antioxidant were changed to the conditions shown in Table 7. Got.

<Production Example 7>
The same as Production Example 1 except that the emulsifier used for the production of rubber latex (H-1) was changed to 2.5 parts by mass of sodium dodecylbenzenesulfonate (trade name: Neoperex G-15, manufactured by Kao Corporation). Thus, a rubbery graft polymer latex was obtained.
A rubbery graft polymer (A′-2) was prepared in the same manner as in Production Example 1 except that the obtained rubbery graft polymer latex was used and the type and amount of antioxidant were changed to the conditions shown in Table 7. )

<Production Example 9>
(Production of polyorganosiloxane rubber latex (L-1))
5 kinds of materials shown in the column of component (5) in Table 5 were mixed, stirred for 5 minutes at 10000 rpm with a homomixer, and then passed twice through a homogenizer at a pressure of 20 MPa to provide a stable premixed organosiloxane emulsion. Got.
The above emulsion was placed in a separable flask equipped with a cooling condenser, and a mixture of 0.20 parts of sulfuric acid and 49.8 parts of distilled water was added over 3 minutes. While this aqueous solution was heated to 80 ° C., the temperature was maintained for 7 hours and then cooled. The reaction was then held at room temperature for 6 hours and then neutralized with aqueous sodium hydroxide.
The polyorganosiloxane rubber latex (L-1) thus obtained was dried at 180 ° C. for 30 minutes to obtain a solid content of 29.8% by mass. The latex had a number average particle size of 384 nm and a volume average particle size of 403 nm.

(Production of silicone / acrylic composite rubbery graft polymer (S-1))
In the reaction vessel containing 10 parts by mass of the polyorganosiloxane rubber latex (L-1) as the polymer solid content, the remaining four materials shown in the column of “initial charge” in Table 6 are added, and the temperature is set to 65. The temperature was raised to ° C. Next, a mixture composed of four kinds of materials shown in the column of “initiator” in Table 6 was added to allow the polymerization to proceed, and then held for 1 hour to perform a polymerization step for the silicone / acrylic composite rubber part.
Thereafter, in the presence of the polymer, a mixture comprising three kinds of materials shown in the column of “graft” in Table 6 was dropped over 45 minutes, and then held for one and a half hours to perform a graft polymerization step. / Acrylic composite rubbery graft polymer latex was obtained.

  The obtained silicone / acrylic composite rubber-like graft polymer latex is added to 460 parts by mass of deionized water containing 5 parts by mass of calcium acetate to coagulate the polymer, washed with water, dehydrated and dried to obtain a silicone / An acrylic composite rubbery graft polymer (S-1) was obtained. Table 7 shows the type and amount of coagulant.

<Evaluation of rubbery graft polymer>
The volume average particle diameter of the rubber particles in the rubber latex, the volume average particle diameter of the rubber graft polymer, the sulfate ion amount, the sulfite ion amount, and the chlorine ion amount in the rubber graft polymer are measured according to the measurement method, The metal corrosion resistance by the rubber graft polymer was evaluated according to the above evaluation method. The results are shown in Tables 8 and 9.

In Tables 8 and 9, “-ROOK” refers to mixed fatty acid potassium and potassium rosinate, “-ROONa” refers to beef tallow fatty acid sodium, and “—SO ₃ Na” refers to sodium dodecylbenzenesulfonate. It is.

"Examples 1-5, Comparative Examples 1-4"
Using a rubber-like graft polymer of the type shown in Table 10, a pellet-shaped polycarbonate resin composition was obtained according to the method for preparing the pellet.
Using the obtained polycarbonate resin composition, test pieces 1 to 3 were produced according to the production method of the test piece, and impact resistance, flame retardancy, and heat resistance colorability were evaluated according to the evaluation method. The results are shown in Table 10.

From the results shown in Table 10, molded articles (test pieces) excellent in heat-resistant coloring properties, flame retardancy and impact resistance were obtained from the polycarbonate resin compositions of the respective examples. Moreover, the rubber-like graft polymer used in each Example was excellent in metal corrosion resistance.
On the other hand, the polycarbonate resin compositions of Comparative Examples 1 and 2 using rubbery graft polymers (A′-1) and (A′-2) having a total amount of sulfate ions and sulfite ions of more than 3.5 ppm were molded. The molded product (test piece) was inferior in heat-resistant colorability. In particular, the molded product obtained in Comparative Example 1 was inferior in flame retardancy.
The rubber-like graft polymer (A′-3) having a chlorine ion content of more than 150 ppm was inferior in metal corrosion resistance. Moreover, the molded article (test piece) which shape | molded the polycarbonate resin composition of the comparative example 3 using the rubber-like graft polymer (A'-3) was inferior also in the flame retardance.
The molded article (test piece) obtained by molding the polycarbonate resin composition of Comparative Example 4 using the silicone / acrylic composite rubbery graft polymer (S-1) was inferior in impact resistance and flame retardancy. Further, YI _B of the molded product is high, the initial color was bad. This is considered to be due to the large difference in refractive index between the polycarbonate resin and the silicone / acrylic composite rubber-like graft polymer (S-1).

  The polycarbonate resin composition of the present invention can provide a molded article excellent in heat-resistant coloring, flame retardancy and impact resistance, and has low corrosiveness to metals. Molded articles obtained by molding the polycarbonate resin composition of the present invention are excellent in heat-resistant coloring, flame retardancy, and impact resistance, and are used in the fields of automobiles, OA equipment such as printers, and electric / electronic fields such as mobile phones. Can be suitably used.

Claims (2)

A polycarbonate resin composition comprising a polycarbonate resin, a flame retardant, polytetrafluoroethylene, and a rubbery graft polymer,
The rubbery graft polymer is a polymer in which the rubbery part contains 50% by mass or more of a diene structural unit or 86% by mass or more of an alkyl (meth) acrylate structural unit,
The total amount of sulfate ions and sulfite ions contained in water extracted from the rubber graft polymer by hot water extraction by the following extraction treatment is 3.5 ppm or less,
And the polycarbonate resin composition whose content of the chlorine ion contained in the said rubber-like graft polymer is 150 ppm or less.
(Extraction process)
200 ml of deionized water is added to 20.0 g of the rubbery graft polymer and extracted at 95 ° C. for 20 hours.   A molded article obtained by molding the polycarbonate resin composition according to claim 1.