JP2000143963A - Frame-retarded resin composition and injection molded product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flame-retarded resin composition that comprises a polycarbonate resin, a styrene resin and phosphoric acid ester, has excellent heat stability, can be recycled, particularly can be stably molded in the injection molding with a hot-runner mold without occurrence of scorching and silvering and produce injection-molded products using the same. SOLUTION: This flame-retarded resin composition comprises (A) 60-97 wt.% of a polycarbonate and (B) 40-3 wt.% of a styrene resin and (C) 1-30 pts.wt., per 100 pts.wt. of the components A and B, of a phosphoric acid ester and the weight reduction in the heating at 260 deg.C for 60 min is <=1 wt.%. In a preferred embodiment, a phosphorous acid ester is mixed as the component (D) in addition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flame-retardant resin composition, and more particularly to a flame-retardant resin composition having excellent thermal stability suitable for molding thin-walled molded articles and large-sized molded articles by injection molding, and the composition. The present invention relates to a flame-retardant injection-molded article having good appearance obtained by injection-molding, particularly, injection molding using a hot runner mold.

[0002]

2. Description of the Related Art Polycarbonate resin has excellent impact resistance, heat resistance, electrical characteristics, and dimensional stability.
It is widely used in various fields such as OA (office automation) devices, information and communication devices, electric and electronic devices, home electric appliances, automobile fields, and construction fields. Polycarbonate resin is generally a self-extinguishing resin, but there are fields where high flame retardancy is required, especially in OA equipment, information and communication equipment, electric and electronic equipment, and home appliances. The improvement has been achieved by adding a flame retardant.

On the other hand, recently, when molded articles are OA equipment such as copying machines, fax machines, personal computers, etc., information and communication equipment such as telephones and communication equipment, electric and electronic equipment, and parts and housings for home electric appliances, etc. Is that the shape becomes complicated, irregularities such as ribs and bosses are formed on the molded product,
From the viewpoints of weight reduction and resource saving, molded articles have been required to have improved melt fluidity, that is, injection moldability, of polycarbonate resins for reasons such as thinning, enlargement, and complexity of molded articles. In order to improve the moldability, many compositions having a rubber-modified styrene resin have been proposed in consideration of physical properties such as impact resistance.

In order to improve the melt fluidity of polycarbonate resin, acrylonitrile-butadiene-styrene resin (ABS resin), rubber-modified polystyrene resin (HIP
S), a composition in which a styrene-based resin such as an acrylonitrile-styrene resin (AS resin) is blended with a polycarbonate resin is used as a polymer alloy in many molded article fields by utilizing its heat resistance and impact resistance properties. Is coming. On the other hand, among these uses, in the case of OA equipment, information equipment, electric / electronic equipment, etc., a certain level of flame retardancy is required in order to enhance the safety of the products.

[0005] As a method for improving the flame retardancy of a resin composition containing a polycarbonate resin as a main component, halogenated flame retardants such as halogenated bisphenol A and halogenated polycarbonate oligomers are difficult to use such as antimony oxide in view of flame retardant efficiency. It has been used with fuel aids. However, in recent years, from the viewpoints of safety at the time of disposal and incineration and adverse effects on the environment, a flame retardant method using a halogen-free flame retardant has been demanded from the market. As a non-halogen flame retardant, an organic phosphorus flame retardant, particularly a polycarbonate resin composition containing an organic phosphate compound exhibits excellent flame retardancy, and many methods have been proposed.

For example, JP-A-61-55145 discloses (A) an aromatic polycarbonate resin and (B) an ABS resin.
Resin, (C) AS resin, (D) halogen compound, (E)
A thermoplastic resin composition comprising a phosphate ester and (F) a polytetrafluoroethylene component is described. JP-A-2-32154 discloses (A) an aromatic polycarbonate resin, (B) an ABS resin, (C) an AS resin,
A flame-retardant high-impact polycarbonate molding composition comprising (D) a phosphate ester and (E) a polytetrafluoroethylene component is described. JP-A-8-239565 discloses (A) an aromatic polycarbonate, (B) a high-impact polystyrene resin containing a rubber-like elastic material, (C) a halogen-free phosphate ester, and (D) a core shell type graft rubber. It describes a polycarbonate resin composition containing an elastic body and (D) talc.

These are all aimed at improving moldability, impact resistance and flame retardancy by improving the melt fluidity of polycarbonate resins, and have been used as various molded articles by taking advantage of their excellent effects. ing. However, when a good melt flowable composition comprising a polycarbonate resin and a (rubber-modified) styrene resin is made flame-retardant with an organic phosphorus-based flame retardant, it is necessary to mix a relatively large amount of a phosphate ester compound. Further, the phosphate compound contributes not only to flame retardancy but also to a plasticizer, and improves melt moldability, that is, injection moldability.

[0008] However, although the resin composition obtained by blending a phosphate ester compound as a flame retardant with a polycarbonate resin and a styrene-based resin composition satisfies the injection moldability itself, it depends on the shape of the molded product and the mold structure. Has poor thermal stability, especially like hot runner molds,
In the case of injection molding in which molten resin stays, burns or silver may easily occur on the surface of the molded product. Therefore, it is difficult to stably mold a molded article having an excellent appearance, and this may not always be satisfactory because it may cause defective products.

Further, depending on the type of the phosphate ester compound, there is also a problem of blooming, and a method has been proposed in which the phosphate ester compound having a high melting point, the monomer and the content of impurities are regulated. However, since the resin composition comprising a polycarbonate resin and a styrene-based resin has a relatively high molding temperature, it is difficult to sufficiently solve the problem of thermal stability by merely selecting a phosphate ester compound.

[0010] For this reason, Japanese Patent Application Laid-Open No. 9-249768 discloses a phosphate ester oligomer cross-linked by the residue of bisphenol A, wherein the content of the specific phosphate ester monomer is 1% by weight or less, and The content is 30 wt ppm or less and heated to 300 ° C. in an inert gas atmosphere at a rate of 100 ° C./min by TGA.
Flame retardants for resins having a weight loss rate of 15% by weight or less for 20 minutes have been proposed. However, no matter how much the phosphoric ester compound is specified as the flame retardant, there is a problem that the thermal stability of the composition of the polycarbonate resin and the styrene resin cannot always be satisfied.

[0011]

SUMMARY OF THE INVENTION Under the above-mentioned circumstances, the present invention relates to a method for flame retarding a composition comprising a polycarbonate resin and a styrene resin, particularly a rubber-modified styrene resin, using a phosphate compound. A flame-retardant resin composition which has excellent heat stability, is recyclable, and can be molded stably without generating burns or silver, even in injection molding using a hot runner mold; and The purpose is to provide injection molded products.

[0012]

Means for Solving the Problems In order to achieve the object of the present invention, the present inventors have studied the heat stability during molding in the flame retardation of a resin comprising a polycarbonate resin and a styrene resin by a phosphate compound. And the appearance of the molded product were studied diligently. As a result, the present inventors have found that a resin composition containing a polycarbonate resin containing a phosphate ester compound as a flame retardant and a styrene-based resin can satisfy the above-mentioned problems when specific conditions are satisfied. completed.

That is, the present invention relates to (1) a phosphoric acid ester (C) based on 100 parts by weight of a resin consisting of (A) 60 to 97% by weight of a polycarbonate resin and (B) 40 to 3% by weight of a styrene resin. Compound 1
A flame-retardant resin composition containing -30 to 30 parts by weight and having a heating loss of 1% by weight or less at a temperature of 260 ° C for 60 minutes. (2) Further, (D) a heat stabilizer is added to (A) and (B)
The flame-retardant resin composition according to the above (1), which is contained in an amount of 0.01 to 2 parts by weight based on 100 parts by weight of the resin comprising: (3) The flame-retardant resin composition according to the above (2), wherein the heat stabilizer is a phosphite compound. (4) Further, (E) fluoroolefin resin,
The flame-retardant resin composition according to any one of the above (1) to (3), which contains 0.05 to 5 parts by weight based on 100 parts by weight of the resin composed of (A) and (B). (5) An injection-molded article obtained by injection-molding the flame-retardant resin composition according to any one of the above (1) to (4). (6) An injection-molded product obtained by injection-molding the flame-retardant resin composition according to any one of (1) to (4) using a hot runner mold. (7) OA equipment, information / communication equipment, electric / electronic equipment or home electric appliance obtained by injection-molding the flame-retardant resin composition according to any of the above (1) to (4) using a hot runner mold. Housings or parts thereof.

Hereinafter, the present invention will be described in detail. (A) Polycarbonate resin The polycarbonate resin (PC) as the component (A) constituting the flame-retardant resin composition of the present invention is not particularly limited, and various ones can be mentioned. Usually, an aromatic polycarbonate produced by a reaction between a dihydric phenol and a carbonate precursor can be used. That is, a product prepared by reacting a dihydric phenol with a carbonate precursor by a solution method or a melting method, that is, a reaction of a dihydric phenol and phosgene by a transesterification method of a dihydric phenol and diphenyl carbonate or the like is used. be able to.

As the dihydric phenol, various ones can be mentioned. In particular, 2,2-bis (4-hydroxyphenyl) propane [bisphenol A], bis (4-hydroxyphenyl) methane, 1,1-bis ( 4-hydroxyphenyl) ethane, 2,2-bis (4-hydroxy-
3,5-dimethylphenyl) propane, 4,4'-dihydroxydiphenyl, bis (4-hydroxyphenyl)
Cycloalkane, bis (4-hydroxyphenyl) oxide, bis (4-hydroxyphenyl) sulfide, bis (4-hydroxyphenyl) sulfone, bis (4-hydroxyphenyl) sulfoxide, bis (4-hydroxyphenyl) ether, bis ( 4-hydroxyphenyl) ketone and the like.

Particularly preferred divalent phenols are bis (hydroxyphenyl) alkanes, particularly those containing bisphenol A as a main raw material. Examples of the carbonate precursor include carbonyl halide, carbonyl ester, and haloformate, and specifically, phosgene, dihaloformate of dihydric phenol, diphenyl carbonate, dimethyl carbonate, and diethyl carbonate. In addition, examples of the dihydric phenol include hydroquinone, resorcin, and catechol. These dihydric phenols may be used alone or in combination of two or more.

The polycarbonate resin may have a branched structure. Examples of the branching agent include 1,1,1-tris (4-hydroxyphenyl) ethane, α, α ′,
α "-tris (4-hydroxyphenyl) -1,3,5
-Triisopropylbenzene, phloroglysin, trimellitic acid, isatin bis (o-cresol) and the like. In order to control the molecular weight, phenol and p-
t-butylphenol, pt-octylphenol,
For example, p-cumylphenol is used.

The polycarbonate resin used in the present invention may be a copolymer having a polycarbonate portion and a polyorganosiloxane portion, or a polycarbonate resin containing this copolymer. Further, it may be a polyester-polycarbonate resin obtained by polymerizing polycarbonate in the presence of a bifunctional carboxylic acid such as terephthalic acid or an ester precursor such as an ester-forming derivative thereof. Also, a mixture of various polycarbonate resins can be used. The polycarbonate resin of the component (A) used in the present invention preferably has substantially no halogen in the structure. Further, from the viewpoint of mechanical strength and moldability, its viscosity average molecular weight is from 10,000 to 100,0.
00, preferably 15,000 to 40,000, particularly preferably 16,000 to 30,000.

(B) Styrene Resin The styrene resin as the component (B) constituting the flame-retardant resin composition of the present invention may be a monovinyl aromatic monomer such as styrene or α-methylstyrene of 20 to 100. % By weight, 0 to 60% by weight of a vinyl cyanide monomer such as acrylonitrile and methacrylonitrile, and 0 to 50 of another vinyl monomer such as maleimide and methyl (meth) acrylate copolymerizable therewith. There is a polymer obtained by polymerizing a monomer or a monomer mixture consisting of wt%. Examples of these polymers include polystyrene (GPPS) and acrylonitrile-styrene copolymer (AS resin).

As the styrene resin, a rubber-modified styrene resin can be preferably used. The rubber-modified styrene resin is preferably an impact-resistant styrene resin obtained by graft-polymerizing at least a styrene monomer onto rubber. Examples of the rubber-modified styrene resin include impact-resistant polystyrene (HIPS) in which styrene is polymerized in rubber such as polybutadiene, ABS resin in which acrylonitrile and styrene are polymerized in polybutadiene, and MBS in which methyl methacrylate and styrene are polymerized in polybutadiene. Resin, rubber-modified styrenic resin,
Two or more of them can be used in combination, and can also be used as a mixture with the above-mentioned rubber-unmodified styrene resin.

The rubber content in the rubber-modified styrenic resin is, for example, 2 to 50% by weight, preferably 5 to 30% by weight, particularly 5 to 15% by weight. 2% by weight of rubber
When the amount is less than 50%, the impact resistance becomes insufficient. When the amount exceeds 50% by weight, problems such as a decrease in thermal stability, a decrease in melt fluidity, generation of a gel, and coloring may occur.
Specific examples of the rubber include a rubber polymer containing polybutadiene, acrylate and / or methacrylate, styrene-butadiene-styrene rubber (SB
S), styrene-butadiene rubber (SBR), butadiene-acrylic rubber, isoprene rubber, isoprene-styrene rubber, isoprene-acrylic rubber, ethylene-propylene rubber and the like. Among them, particularly preferred is polybutadiene. The polybutadiene used here is a low cis polybutadiene (for example, 1 to 30 mol% of 1,2-vinyl bond and 30 to 42% of 1,4-cis bond).
Mol%) or high cis polybutadiene (for example, those containing 1,2-vinyl bonds of 20 mol% or less and 1,4-cis bonds of 78 mol% or more). May be used.

The flame-retardant resin composition of the present invention improves the melt fluidity of the resin composition by blending a styrene resin with a polycarbonate resin. here,
The mixing ratio of both resins is (A) polycarbonate resin 60 to
97% by weight, preferably 70 to 95% by weight, and (B) the styrene resin is 40 to 3% by weight, preferably 30 to 5% by weight. Here, when the content of the polycarbonate resin as the component (A) is less than 60% by weight, heat resistance and strength are not sufficient.
If the amount of the styrene resin (B) is less than 3% by weight, the effect of improving the moldability is insufficient. In this case, as the styrene resin (B), the above-mentioned rubber-modified styrene resin is preferably used. These compounding ratios are appropriately determined in consideration of the molecular weight of the polycarbonate resin, the type and molecular weight of the styrene resin, the melt index, the rubber content, the use of the molded product, the size, the thickness, and the like.

(C) Phosphate Ester Compound The phosphate ester compound of component (C) constituting the flame-retardant resin composition of the present invention is not particularly limited, and is preferably a compound containing no halogen. (1)

[0024]

Embedded image

(Where R ¹ , R ² , R ³ , and R ⁴ each independently represent a hydrogen atom or an organic group, and X represents 2
Represents an organic group having a valence of at least 1, p is 0 or 1, and q is 1
And r represents an integer of 0 or more. ). In equation (1),
The organic group includes an alkyl group, a cycloalkyl group and an aryl group which may or may not be substituted. Examples of the substituent when it is substituted include an alkyl group, an alkoxy group, an aryl group, an aryloxy group, and an arylthio group. Further, those having a substituent such as an arylalkoxyalkyl group which is a group obtained by combining these substituents, or an arylsulfonylaryl group obtained by combining these substituents by bonding with an oxygen atom, a nitrogen atom, a sulfur atom, or the like. and so on.

In the formula (1), as the divalent or higher valent organic group X, a divalent or higher valent group formed by removing one or more hydrogen atoms bonded to a carbon atom from the above-mentioned organic groups is used. means. For example, those derived from an alkylene group, a (substituted) phenylene group, and bisphenols which are polynuclear phenols. Preferred are bisphenol A, hydroquinone, resorcinol, diphenylmethane, dihydroxydiphenyl, dihydroxynaphthalene and the like.

The phosphate compound may be a monomer, oligomer, polymer or a mixture thereof. Specifically, trimethyl phosphate, triethyl phosphate, tributyl phosphate, trioctyl phosphate, tributoxyethyl phosphate, triphenyl phosphate, tricresyl phosphate, cresyl diphenyl phosphate, octyl diphenyl phosphate, tri (2-ethylhexyl) phosphate, diisopropyl Phenyl phosphate, trixylenyl phosphate, tris (isopropylphenyl) phosphate, trinaphthyl phosphate, bisphenol A bisphosphate, hydroquinone bisphosphate, resorcin bisphosphate, resorcinol-diphenyl phosphate, trioxybenzene triphosphate, cresyl diphenyl phosphate, or these Substitutes, condensates, etc. It can be exemplified.

Here, commercially available halogen-free phosphate ester compounds include, for example, TPP [triphenyl phosphate], TXP manufactured by Daihachi Chemical Industry Co., Ltd.
[Trixylenyl phosphate], PFR [resorcinol (diphenyl phosphate)], PX200 [1,
3-phenylene-teslakis (2,6-dimethylphenyl) phosphate, PX201 [1,4-phenylene-tetrakis (2,6-dimethylphenyl) phosphate, PX202 [4,4'-biphenylene-teslakis) 2 , 6-dimethylphenyl) phosphate and the like.

The content of the phosphoric acid ester compound as the component (C) is 1 to 100 parts by weight of the resin (A) containing the polycarbonate resin and (B) the styrene resin.
It is 30 parts by weight, preferably 3 to 20 parts by weight, more preferably 5 to 15 parts by weight. Here, if the content is less than 1 part by weight, the flame retardancy of the molded article is not sufficient, and if it exceeds 30 parts by weight, the strength such as heat resistance and impact resistance of the molded article may be reduced.

The flame-retardant resin composition of the present invention comprises (A)
It is obtained by melt-kneading the resin component consisting of (B) and (C). The kneading method is not particularly limited, and (1) a method in which the three components are simultaneously mixed and supplied to various melt-kneading apparatuses to produce. (2) A method in which a polycarbonate resin and a styrene-based resin are melt-kneaded, and then a phosphate ester compound is added and melt-kneaded. (3) A method in which a polycarbonate resin and a styrene-based resin are supplied to a kneader, melt-kneaded, and a phosphate ester compound is supplied in a solid, liquid, or molten state and kneaded in the middle of the kneader. (4)
For example, a method in which a phosphate ester compound is melt-kneaded in a polycarbonate resin in advance and then a styrene resin is added and kneaded. The flame-retardant resin composition of the present invention is generally prepared by these melt-kneading methods,
As a pellet of an arbitrary shape, it is used as a molding raw material for molding a final molded article.

The feature of the flame-retardant resin composition of the present invention resides in that the loss on heating at 260 ° C. for 60 minutes is controlled to 1% by weight or less. If the weight loss on heating exceeds 1% by weight, silver, which is considered to be due to gas generated during molding, may be generated on the surface of the molded product, and burning may occur depending on molding conditions. In addition, the molded product adheres to the surface of the mold during molding, and the releasability is deteriorated, so that continuous molding cannot be performed and productivity may be reduced. Furthermore, when recycled, the color tone may change significantly. Therefore, the heat loss is preferably 0.8% by weight or less, particularly preferably 0.6% by weight or less.

Here, the weight loss by heating means that the composition sample is
It can be measured by analyzing with a (thermal balance). That is, it can be defined as the weight loss% when about 20 mg of the composition sample is heated to 260 ° C. in a stream of nitrogen or helium at a rate of 100 ° C./min and held for 60 minutes. . In addition, the composition sample is previously 80
Pretreatment of drying at 8 ° C. for 8 hours removes moisture absorption and the like.

The flame-retardant resin composition of the present invention can be produced by employing various means as long as the above-mentioned heat loss is satisfied. Examples of these means include selection of a raw material resin and a phosphate compound, selection of a melt-kneading apparatus for producing a composition, selection of melt-kneading conditions, addition of an additive, or a combination thereof. Especially, addition of a heat stabilizer etc. as an additive is preferable.

(D) Heat stabilizer The heat stabilizer is an additive for preventing thermal oxidative deterioration of the flame-retardant resin composition, and includes a phosphorus-based antioxidant, a phenol-based antioxidant, and a sulfur-based antioxidant. And the like. Among them, phosphorus antioxidants, particularly phosphite compounds are preferably used. The phosphite compound is an ester compound in which hydrogen of phosphorous acid is independently substituted with an alkyl group, an aryl group, an alkyl-substituted aryl group, or the like.

As these phosphite compounds,
Trimethyl phosphite, triethyl phosphite, tributyl phosphite, tri (2-ethylhexyl) phosphite, tributoxyethyl phosphite, triphenyl phosphite, tricresyl phosphite, trixylenyl phosphite, tris (isopropylphenyl) phosphite Phytite, tris nonylphenyl phosphite, tris (2,4-di-t-butylphenyl) phosphite, trinaphthyl phosphite, cresyl diphenyl phosphite, xylenyl diphenyl phosphite,
Dibutyl phosphite, distearyl pentaerythritol diphosphite, bis (2,4-di-t-butylphenyl) pentaerythritol phosphite, bis (2,6-di-t-butyl-4-methylphenyl) pentaerythritol phosphite Phyte, 2,2-methylenebis (4,6-di-butylphenyl) octyl phosphite, tetrakis (2,4-di-t-butylphenyl)-
4,4'-biphenylene-di-phosphite and the like can be exemplified. Among these, triphenyl phosphite,
Tricresyl phosphite, trisnonylphenyl phosphite, tris (2,4-di-tert-butylphenyl)
Phosphite and the like are preferably used.

The content of the phosphite compound is 0.01 to 2 parts by weight, preferably 0.1 to 1 part by weight, based on 100 parts by weight of the polycarbonate resin (A) and the styrene resin. . Here, if the content of the phosphite compound is less than 0.01 part by weight, the effect of improving the thermal oxidation stability is small, and if it exceeds 2 parts by weight, the heat resistance is reduced and inconveniences such as gas generation during molding may occur. There may be.

For the flame-retardant resin composition of the present invention, it is desirable to select a raw material having a low molecular weight component in the polycarbonate resin as a raw material. Further, as a styrene-based resin, as a polymerization method, compared with a polymerization method using a suspension or emulsion stabilizer such as suspension polymerization or emulsion polymerization, these additives are not required, obtained by bulk polymerization. It is preferable to use a resin. As for the styrene resin, it is preferable to select a resin having a low content of a low molecular component, as in the case of the polycarbonate resin. It is also important to avoid selecting highly volatile compounds as phosphate compounds.

In order to obtain the flame-retardant resin composition of the present invention, in addition to the selection of the raw material resin and the addition of the heat stabilizer, melt kneading conditions include a melt kneading molding machine with a vent, particularly a melt kneading with a vent. It is preferable to forcibly evacuate from the vent during melt-kneading using an extruder to remove volatile components to a certain level as much as possible. The flame-retardant resin composition of the present invention may further contain (E) a fluoroolefin resin for the purpose of preventing melting and dropping during combustion. Here, (E) the fluoroolefin resin is usually a polymer or copolymer containing a fluoroethylene structure, for example, a difluoroethylene polymer, a tetrafluoroethylene polymer, a tetrafluoroethylene-hexafluoropropylene copolymer, It is a copolymer of tetrafluoroethylene and an ethylene monomer containing no fluorine. Preferably, it is polytetrafluoroethylene (PTFE), and the average molecular weight is preferably 500,000 or more, and particularly preferably 500,000 to 10,000.
00,000.

When polytetrafluoroethylene having a fibril-forming ability is used, higher anti-dripping properties can be imparted. Polytetrafluoroethylene (PTF) having fibril-forming ability
E) is not particularly limited, and includes, for example, those classified into type 3 in the ASTM standard. Specific examples thereof include, for example, Teflon 6-J (manufactured by Dupont Fluorochemicals Mitsui), Polyflon D-1, Polyflon F-103, Polyflon F201L (manufactured by Daikin Industries, Ltd.), and CD076 (Asahi ICI Fluoropolymers Co., Ltd.) Manufactured by a company).

Other than those classified into the above-mentioned type 3, for example, Algoflon F5 (manufactured by Montefluos), polyflon MPA, polyflon FA-100
(Manufactured by Daikin Industries, Ltd.). These polytetrafluoroethylene (PTFE) may be used alone or in combination of two or more. Polytetrafluoroethylene (PTFE) having a fibril-forming ability as described above can be obtained, for example, by mixing tetrafluoroethylene in an aqueous solvent in the presence of sodium, potassium, and ammonium peroxydisulfide at 1 to 100 psi.
Under a pressure of 0 to 200 ° C., preferably 20 to 100 ° C.
It is obtained by polymerizing at ° C.

Here, the content of the fluoroolefin resin is from 0.05 to 5 parts by weight, preferably from 0.1 to 5 parts by weight, based on 100 parts by weight of the resin consisting of (A) and (B).
2 parts by weight. Here, if the amount is less than 0.05 part by weight, the melt dripping resistance in the intended flame retardancy may not be sufficient. Even if the amount exceeds 5 parts by weight, the effect corresponding thereto is not improved, and The impact and the appearance of the molded product may be adversely affected. Therefore, the degree of flame retardancy required for each molded article, for example, V-0 and V- of UL-94.
It can be appropriately determined in consideration of the amount of other components to be used and the like according to 1, V-2, and the like.

The flame-retardant resin composition of the present invention further comprises:
The rubber-like elastic body as the component (F) can be contained for further improving the impact resistance of the flame-retardant resin composition. The content is 1 to 30 parts by weight, preferably 2 to 20 parts by weight, based on 100 parts by weight of the resin composed of (A) and (B). The content of this rubber-like elastic body is
Determined in comprehensive consideration of the impact resistance, heat resistance, rigidity, etc. required for the target molded product. Examples of the rubber-like elastic body include polybutadiene, polyisoprene, styrene / butadiene / styrene rubber (SBS), styrene / butadiene rubber (SBR), butadiene / acrylic rubber, isoprene / styrene rubber, isoprene / acrylic rubber, ethylene / propylene rubber, Examples include ethylene propylene diene rubber and siloxane rubber.

The rubber-like elastic body of the component (F) has a two-layer structure composed of a core and a shell, and the core is in a soft rubber state. The shell part is preferably a hard resin state, and the elastic body itself is preferably a core-shell type graft rubber-like elastic body in a powder state (particle state). Even after the rubber-like elastic body is melt-blended with the polycarbonate resin, the particle state of the rubber-like elastic body mostly maintains its original form. Since most of the compounded rubber-like elastic body maintains the original shape, an effect of preventing surface layer peeling can be obtained.

Various examples of the core-shell type graft rubber-like elastic body can be given. Examples of commercially available products include Hybrene B621 (manufactured by Zeon Corporation), KM-330 (manufactured by Rohm & Haas Co., Ltd.), Metablen W529, Metablen S2001, Metablen C223, and Metablen B621 (manufactured by Mitsubishi Rayon Co., Ltd.). Can be

Among them, for example, one or more vinyl monomers are added in the presence of a rubbery polymer obtained from a monomer mainly composed of alkyl acrylate, alkyl methacrylate or dimethyl siloxane. Examples include those obtained by polymerization. Here, alkyl acrylates and acrylic methacrylates have 2 to 1 carbon atoms.
Those having a zero alkyl group are preferred. In particular,
For example, ethyl acrylate, butyl acrylate, 2-
Examples include ethylhexyl acrylate and n-octyl methacrylate. The rubber-like elastic material obtained from these monomers mainly composed of alkyl acrylates includes 70% by weight or more of alkyl acrylates and another vinyl monomer copolymerizable therewith, such as methyl methacrylate and acrylonitrile. , Vinyl acetate, styrene, and the like, and 30% by weight or less. In this case, a polyfunctional monomer such as divinylbenzene, ethylene dimethacrylate, triallyl cyanurate, triallyl isocyanurate or the like may be appropriately added as a crosslinking agent and reacted.

Examples of the vinyl monomer to be reacted in the presence of the rubbery polymer include aromatic vinyl compounds such as styrene and α-methylstyrene, acrylates such as methyl acrylate and ethyl acrylate, and methacrylic acid. And methacrylates such as methyl acrylate and ethyl methacrylate. These monomers may be used alone or in combination of two or more. Further, other vinyl polymers such as vinyl cyanide compounds such as acrylonitrile and methacrylonitrile, vinyl acetate, and propionic acid It may be copolymerized with a vinyl ester compound such as vinyl. This polymerization reaction can be performed by various methods such as bulk polymerization, suspension polymerization, and emulsion polymerization. In particular,
Emulsion polymerization is preferred.

The core-shell type graft rubber-like elastic material thus obtained preferably contains the rubber-like polymer in an amount of 20% by weight or more. Specific examples of such a core-shell type graft rubber-like elastic material include M-polymers such as a graft copolymer of 60 to 80% by weight of n-butyl acrylate, styrene and methyl methacrylate.
AS resin elastic body is mentioned. Above all, the polysiloxane rubber component has a structure in which 5-95% by weight of the polyacryl (meth) acrylate rubber component and 95-5% by weight of the polyacryl (meth) acrylate rubber component are entangled with each other so as to be inseparable.
A composite rubber-based graft copolymer obtained by graft-polymerizing at least one vinyl monomer on a composite rubber having a size of about 01 to 1 μm is preferable. The copolymer has a higher impact resistance improving effect than the graft copolymer of each rubber alone.
This composite rubber-based graft copolymer, as a commercial product,
Available as Mitsubishi Rayon Co., Ltd. Metablen S-2001.

Further, the flame-retardant resin composition of the present invention may further contain an inorganic filler in order to further improve the rigidity and the flame retardancy of the molded article. Here, as the inorganic filler, talc, mica, kaolin,
Diatomaceous earth, calcium carbonate, calcium sulfate, barium sulfate, glass fiber, carbon fiber, potassium titanate fiber and the like can be mentioned. Above all, plate-like talc,
Mica and the like and fibrous fillers are preferred. As the talc, a hydrated silicate of magnesium, which is generally commercially available, can be used. The average particle size of the inorganic filler such as talc is 0.1 to 50 μm, preferably 0.2 to 20 μm. These inorganic fillers,
In particular, by adding talc, in addition to the effect of improving rigidity, the amount of the phosphate compound as a flame retardant can be reduced.

Here, the content of the inorganic filler is 1 to 100 parts by weight, preferably 2 to 50 parts by weight, based on 100 parts by weight of the resin composed of the above (A) and (B). If the amount is less than 1 part by weight, the intended effect of improving the rigidity and the flame retardancy may not be sufficient. If the amount exceeds 100 parts by weight, the impact resistance and the melt fluidity may decrease. It can be appropriately determined in consideration of the required properties and moldability of the molded article, such as the thickness of the article and the resin flow length.

The flame-retardant resin composition of the present invention is used for improving moldability, impact resistance, appearance, weather resistance, rigidity and the like.
The essential components consisting of the above (A) to (C) include (D) to
(F) In addition, inorganic fillers and various additive components commonly used in thermoplastic resins can be contained as necessary. For example, an antistatic agent, a polyamide polyether block copolymer (providing permanent antistatic performance), a benzotriazole-based or benzophenone-based ultraviolet absorber, a hindered amine-based light stabilizer (weathering agent), an antibacterial agent, a compatibilizer,
Coloring agents (dyes, pigments) and the like can be mentioned. The amount of the optional component is not particularly limited as long as the properties of the flame-retardant resin composition of the present invention are maintained.

Next, a method for producing the flame-retardant resin composition of the present invention will be described. The flame-retardant resin composition of the present invention comprises the above-mentioned components (A) to (C) in the above-mentioned proportions, and various optional components (D) to (F) used as needed. By mixing and kneading the components in an appropriate ratio. The compounding and kneading at this time are preliminarily mixed with a commonly used device, for example, a ribbon blender, a drum tumbler, etc., and a Henschel mixer, a Banbury mixer, a single screw extruder, a twin screw extruder, a multi-screw extrusion. Can be carried out by using a machine, a kneader or the like. However, as described above, it is preferable to employ a continuous extruder such as a single-screw extruder or a multi-screw extruder, which employs a forced-vent exhaust type. Further, as the extruder, one having a plurality of raw material supply units in the flow direction of the forming raw material can also be suitably used. For example, a method in which raw material components other than the phosphate compound are melt-kneaded, a method in which the phosphate compound is supplied to the kneaded product, preferably in a molten state, the polycarbonate resin and the phosphate compound are first melt-kneaded, and then the styrene-based compound is mixed. A method of kneading with a resin can be exemplified.

The heating temperature during the melt-kneading is usually from 240 to
It is appropriately selected within a range of 300 ° C. The components other than the polycarbonate resin and the styrene-based resin may be previously melt-kneaded with the polycarbonate resin, the styrene-based resin, or another thermoplastic resin, that is, added as a master batch. The flame-retardant resin composition of the present invention is obtained by using the above-mentioned melt-kneading molding machine, or the obtained pellets as a raw material, by using an injection molding method, an injection compression molding method, an extrusion molding method, a blow molding method, a press molding method, and a vacuum molding method. Various molded products can be manufactured by a molding method, a foam molding method, or the like. However, the flame-retardant resin composition of the present invention is, by the above-described melt-kneading method, a pellet-shaped composition molding raw material,
Then, the pellets can be suitably used for the production of injection molded products by injection molding or injection compression molding. In addition, as the injection molding method, gas injection molding for preventing sink marks on the appearance or for reducing the weight can be employed.

Therefore, the flame-retardant resin composition of the present invention is a molded product after melt-kneading or a pellet-shaped molding raw material after melt-kneading, wherein the heated raw material at 260 ° C. for 60 minutes is 1% by weight or less. It is. By satisfying this condition, the flame-retardant resin composition of the present invention can be suitably used not only for a direct gate type but also for molding a molded product using a hot runner mold. That is,
In the hot runner mold, due to the stagnation of the molten resin in the hot runner, it is susceptible to heat history and is liable to generate gas and coloring due to decomposition of the resin and the like, and it is difficult to mold a molded article having a good appearance, The present invention solves these problems. Therefore, the flame-retardant resin composition of the present invention can enable the molding of a thin-walled molded product or a large-sized molded product using a hot runner mold.

Injection molded articles (including injection compression) obtained from the flame-retardant resin composition of the present invention include copying machines, fax machines, televisions, radios, tape recorders, video decks, personal computers, printers, telephones, and information terminals. It is also used in other fields such as machines, refrigerators, OA devices such as microwave ovens, information and communication devices, electric and electronic devices or housings for home electric appliances or various components thereof, and also automotive parts.

[0055]

EXAMPLES The present invention will be described more specifically with reference to examples and comparative examples, but the present invention is not limited thereto. Examples 1 to 3 and Comparative Examples 1, 2 and 4 [Blends in the proportions shown in Table 1 (components (A) and (B) are% by weight,
The other components are shown in parts by weight based on 100 parts by weight of the resin composed of (A) and (B). ] To obtain a composition, a biaxial (co-rotating) screw extruder [TEM-35,
L / D = 32, equipped with a first raw material supply port (hopper), a forced exhaust vent hole, and a second raw material supply port (liquid side feed). ] To perform melt-kneading extrusion. Raw material components other than the phosphate ester compound were supplied from the first raw material supply port, and the phosphate ester compound was supplied from the second raw material supply port. The melt-kneading temperature is 2
80 ° C., rear part: 260 ° C.

After the obtained pellets were dried at 80 ° C. for 8 hours, the loss on heating at 260 ° C. for 60 minutes was measured using TGA (thermal analysis) under the conditions described above. The results are shown in Table 1. Show. Further, using these pellets, an injection molding machine [Toshiba IS650t]: injection molding is performed at a molding temperature of 240 ° C., a hot runner temperature of 260 ° C., and a mold temperature of 60 ° C. using a hot runner type OA housing molding die.
A housing (for CRT) was obtained. Table 1 shows the evaluation results of the appearance of the molded product. Next, a molding temperature of 260 ° C. and a mold temperature of 4
The OA housing was similarly molded at 0 ° C., and the results of visual observation of the mold surface after 100 shots are shown in Table 1. Also, the OA housing, which is a molded product, is pulverized to 100%
The OA housing was molded under the former condition by using it as a recycled material, and the change in color tone before and after was measured. In addition, a test piece was separately molded using a general mold for molding a test piece, and the flame retardancy and impact strength were measured.
Shown in

Comparative Example 3 The procedure of Example 1 was repeated, except that all of the molding raw materials were supplied from the first raw material supply port, and no forced exhaust was performed through the vent hole. Table 1 shows the evaluation results. In all Examples and Comparative Examples, 0.2 parts by weight of Irganox 1076 (manufactured by Ciba Specialty Chemicals) was added as an antioxidant.

The molding raw materials used and the performance evaluation methods are shown below. (A) Polycarbonate resin PC: Toughlon (A1900: manufactured by Idemitsu Petrochemical Co., Ltd.), bisphenol A polycarbonate resin, MI:
20 g / 10 min (300 ° C., 1.2 Kg load), viscosity average molecular weight: 19000 (B) Styrene resin HIPS: Impact resistant polystyrene resin (IDEMITSU)
PS IT44: manufactured by Idemitsu Petrochemical Co., Ltd.), polybutadiene grafted with styrene, rubber content: 10% by weight, MI: 8 g / 10 min (200 ° C., 5
ABS-1: Acrylonitrile butadiene styrene copolymer obtained by bulk polymerization (AT-05: manufactured by Mitsui Chemicals, Inc.), MI: 5 g / 10 min (200 ° C., 5 Kg load) ABS-2: Emulsion polymerization Acrylonitrile butadiene styrene copolymer (DP-611: manufactured by Techno Polymer Co., Ltd.), MI: 2 g / 10 min (200 ° C., 5K
g load)

(C) Phosphate ester compound P-1: resorcinol bis (diphenyl phosphate): phosphate ester PFR (manufactured by Asahi Denka Kogyo Co., Ltd.) P-2: triphenyl phosphate: TPP (manufactured by Daihachi Chemical Co., Ltd.) (D) Phosphorous ester compound Tris (2,4-di-t-butylphenyl) phosphite: Irgafos 168 (manufactured by Ciba Specialty Chemicals) (E) Fluoroolefin resin PTFE: F201L (Daikin Chemical Industries) (F) Rubber-like elastic material (core-shell type graft rubber-like elastic material) Composite rubber-based graft copolymer (METABLEN S2001:
Mitsubishi Rayon Co., Ltd.), polydimethylsiloxane content: 50% by weight or more

[Performance Evaluation Method] (1) Moldability (molded product appearance): Observation of appearance (2) Moldability (mold adhesion): (3) Recyclability [Color tone change ΔE]: JIS K
The hue (L, a, b) of the molded article was measured with a color difference meter in accordance with 7103 (Yellowness degree test method) and calculated as a hue change ΔE. (5) Flame retardancy Compliant with UL94 combustion test (test piece thickness: 1.5 mm) (6) IZOD impact strength According to ASTM D256, 23 ° C (1/8 inch wall thickness), unit kJ / m ²

[0061]

[Table 1]

As is clear from the results shown in Table 1, the molded article made of the flame-retardant resin composition of the present invention shows no generation of silver and no burning while using the hot runner mold.
In addition, the color tone change ΔE at the time of recycling is small, and reuse becomes possible.

[0063]

Industrial Applicability The flame-retardant resin composition of the present invention is halogen-free, has excellent flame retardancy and impact strength, suppresses decomposition of resin and the like at the time of molding due to improved heat resistance, and provides a molded article appearance. Excellent. In particular, even in molding using a hot runner mold that has been frequently used recently, molding can be performed with almost no occurrence of burning, silver, and adhesion to the mold. Therefore, it can sufficiently cope with the increase in size and thickness of OA equipment, information / communication equipment, electric / electronic equipment, home electric appliances, automobile parts, and the like, and its application fields are expected to expand.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat (Reference) C08L 25:04 27:12) B29K 69:00 B29L 31:00 F term (Reference) 4F206 AA12 AA13 AA28 AB05 AC01 AH33 AH41 AH42 AH53 JA07 JF01 JF02 JL02 JQ81 4J002 BC032 BC042 BC062 BD154 BD164 CG011 CG021 CQ013 EW046 EW056 EW067 FD067 FD133 FD136 GQ01

Claims (7)

[Claims] 1. (A) polycarbonate resin 60 to 97
(C) 1 to 30 parts by weight of a phosphoric ester compound with respect to 100 parts by weight of a resin composed of 40 to 3% by weight of a styrene resin, and heating at 260 ° C. for 60 minutes. A flame-retardant resin composition having a weight loss of 1% by weight or less. 2. The method according to claim 1, further comprising adding (D) a heat stabilizer to 0.01 parts by weight of the resin comprising (A) and (B).
The flame-retardant resin composition according to claim 1, wherein the composition comprises from 2 to 2 parts by weight. 3. The flame-retardant resin composition according to claim 2, wherein the heat stabilizer is a phosphite compound. 4. The method according to claim 1, further comprising 0.05 to 5 parts by weight of the fluoroolefin resin (E) based on 100 parts by weight of the resin comprising (A) and (B). The flame-retardant resin composition according to the above. 5. An injection-molded product obtained by injection-molding the flame-retardant resin composition according to claim 1. 6. An injection-molded article obtained by injection-molding the flame-retardant resin composition according to claim 1 by using a hot runner mold. 7. An OA device, an information / communication device, an electric / electronic device or a home electric appliance obtained by injection-molding the flame-retardant resin composition according to claim 1 using a hot runner mold. Housings or their parts.