JP3432069B2 - Polycarbonate flame retardant resin composition - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a polycarbonate-based flame-retardant resin composition having excellent heat resistance and impact resistance and high flame retardancy.

[0002]

2. Description of the Related Art A blend of a polycarbonate resin and a styrene resin represented by ABS resin has high heat resistance and impact resistance.
It is widely used in various molded products such as automobiles, electric and electronic parts. The polymer alloy is electrically
Flame retardancy is required when used for housings, enclosures, chassis of electronic parts and office automation (OA) equipment.

In particular, in recent years, in order to improve the safety of products,
Molded products such as OA equipment and home appliances may be required to certify the flame retardancy level V-0 or 5V based on Subject 94 of Underwriters Laboratories (UL), which is a flame retardancy standard in the United States. Many.

On the other hand, in order to reduce the amount of materials used,
It is useful to reduce the size and thickness of parts and housings. However, during combustion, molten dripping (drip) of the resin occurs from the thin portion of the molded product, and there is a risk of spreading other combustible materials.
Therefore, the flame-retardant resin composition is also required to have a high degree of flame-retardant property without dripping.

In order to impart flame retardancy, a halogen compound is usually added to the polymer alloy of polycarbonate and styrene resin. However, the halogen-based compound has a drawback that a corrosive or toxic gas is generated during processing or combustion. Therefore, development of a non-halogen flame retardant with less of these drawbacks is desired.

Organophosphorus compounds are used as non-halogen flame retardants. Triphenyl phosphate is well known as a typical organic phosphorus compound,
Triphenyl phosphate has the disadvantages of poor heat resistance and high volatility.

As the organic phosphoric acid compound having low volatility,
There are condensed phosphoric acid esters described in US Pat. No. 5,204,394 and US Pat. No. 5,122,556. These have better heat resistance than triphenyl phosphate,
Considering the balance with flame retardancy, it is not enough yet. Further, many of these condensed phosphoric acid esters are liquid compounds, which lowers the physical properties of the resin such as lowering the heat distortion temperature of the resin compound.

[0008]

Therefore, the object of the present invention is to provide a polycarbonate having high heat resistance and impact resistance, which does not generate corrosive or toxic gas upon combustion and has excellent flame retardancy. An object is to provide a flame-retardant resin composition.

[0009]

Means for Solving the Problems The inventors of the present invention have conducted extensive studies to achieve the above object, and as a result, by using a condensed phosphoric acid ester compound in combination with a specific organic phosphorus compound as a non-halogen flame retardant. The inventors have completed the present invention by finding that molded products having excellent heat resistance and impact resistance, which are not obtained by using each of them alone, and having high flame retardancy can be obtained.

That is, the present invention includes (A) an aromatic polycarbonate, (B) a styrene resin, (C) the following general formula (I):
A condensed phosphoric acid ester compound represented by (D) an organic phosphorus compound represented by the following general formula (II), and optionally a resin composition composed of (E) a fluororesin, In addition, (D) the organophosphorus compound in the resin composition and (C)
The present invention relates to a polycarbonate-based flame-retardant resin composition having a phosphorus concentration ratio (P _D / P _C ) with a condensed phosphoric acid ester compound of less than 2 (not substantially including 0).

[0011]

[Chemical 3]

[Wherein R ^{1 to} R ⁴ are phenyl groups which may have an alkyl group having 1 to ⁴ carbon atoms, and R ^{1 to} R ⁴ may be the same or different, and A is A phenylene group, n is an integer of 1 to 5. ]

[0013]

[Chemical 4]

[In the formula, R ⁵ and R ⁶ are phenyl groups which may have 1 to 3 alkyl groups having 1 to 4 carbon atoms, and R ⁵ and R ⁶ may be the same or different. . ]

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The aromatic polycarbonate which is the component A of the present invention is obtained by a reaction of various dihydroxyaryl compounds with phosgene, or obtained by a transesterification reaction of a dihydroxyaryl compound and diphenyl carbonate. There are things.
A typical example is a polycarbonate obtained by the reaction of 2,2'-bis (4-hydroxyphenyl) propane and phosgene.

Examples of dihydroxyaryl compounds used as raw materials for polycarbonate include bis (4-hydroxyphenyl) methane and 1,1'-bis (4-hydroxyphenyl)
Ethane, 2,2'-bis (4-hydroxyphenyl) propane, 2,2'-bis (4-hydroxyphenyl) butane, 2,
2'-bis (4-hydroxyphenyl) octane, 2,2'-
Bis (4-hydroxy-3-methylphenyl) propane, 2,2'-bis (4-hydroxy-3-t-butylphenyl) propane, 2,2'-bis (3,5-dimethyl-4-hydroxyphenyl) ) Propane, 2,2'-bis (4-hydroxy-3-cyclohexylphenyl) propane, 2,2'-bis (4-hydroxy-3-methoxyphenyl) propane, 1,1'-bis (4-hydroxyphenyl) ) Cyclopentane, 1,1'-bis (4-hydroxyphenyl) cyclohexane, 1,1'-bis (4-hydroxyphenyl) cyclododecane, 4,4'-dihydroxyphenyl ether, 4,4 '
-Dihydroxy-3,3'-dimethylphenyl ether, 4,
4'-dihydroxydiphenyl sulfide, 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfide, 4,4'-
Examples include dihydroxydiphenyl sulfoxide, 4,4′-dihydroxydiphenyl sulfone, and bis (4-hydroxyphenyl) ketone. These dihydroxyaryl compounds may be used alone or in combination of two or more.

Preferred dihydroxyaryl compounds include bisphenols, which form highly heat-resistant aromatic polycarbonate, bis (hydroxyphenyl) alkanes such as 2,2'-bis (4-hydroxyphenyl) propane, and bis (4-hydroxy). And bis (hydroxyphenyl) cycloalkanes such as phenyl) cyclohexane, dihydroxydiphenyl sulfide, dihydroxydiphenyl sulfone, dihydroxydiphenyl ketone, and the like. Particularly preferred dihydroxyaryl compounds include
Form bisphenol A type aromatic polycarbonate
2,2'-bis (4-hydroxyphenyl) propane is included.

In the production of the bisphenol A type aromatic polycarbonate, a part of the bisphenol A may be replaced with another dihydroxyaryl compound as long as the heat resistance and the mechanical strength are not impaired.

The styrene resin which is the component B of the present invention is a homopolymer or copolymer of styrene or a styrene derivative such as α-methylstyrene or vinyltoluene, and these monomers and acrylonitrile or methylmethacrylate. Copolymers with vinyl monomers, diene rubbers such as polybutadiene, ethylene / propylene rubbers, acrylic rubbers, etc. with styrene and / or styrene derivatives,
Alternatively, it is a product obtained by graft-polymerizing styrene and / or a styrene derivative and another vinyl monomer, for example, polystyrene, high-impact polystyrene, AS resin, ABS.
Resin, AAS resin, AES resin, etc.

The above-mentioned (A) aromatic polycarbonate and (B)
When a styrene resin is melt-mixed, a so-called polymer alloy is formed, and a molded article having high heat resistance and impact resistance can be obtained. The ratio of the aromatic polycarbonate to the styrene resin can be selected within a range that does not impair heat resistance, impact resistance, melt fluidity, etc., for example, A / B = 40 to 95/60 to 5 (wt%), preferably It is about 50 to 95/50 to 5 (% by weight), and more preferably about 55 to 85/45 to 15 (% by weight). When the content of the aromatic polycarbonate is less than 40% by weight, the melt flowability is high, but the heat resistance and impact resistance of the molded product are liable to decrease, and when it exceeds 95% by weight, the melt flowability in the molding process decreases. Cheap.

The feature of the present invention is that by using the condensed phosphoric acid ester compound which is the C component and the organic phosphorus compound which is the D component in combination, excellent mechanical properties and high difficulty which cannot be obtained by using each independently. The point is that a resin molded product having both flammability can be obtained.

The condensed phosphoric acid ester compound (C) is represented by the following general formula (I).

[0023]

[Chemical 5]

[Wherein, R ^{1 to} R ⁴ are phenyl groups which may have an alkyl group having 1 to ⁴ carbon atoms, and R ^{1 to} R ⁴ may be the same or different, and A is A phenylene group, n is an integer of 1 to 5. In the general formula (I), examples of the alkyl group which may be substituted on the phenyl group represented by R ^{1 to} R ⁴ include, for example, methyl, ethyl, propyl, isopropyl, butyl, isobutyl and s.
Examples thereof include lower alkyl groups having about 1 to 4 carbon atoms such as -butyl and t-butyl groups. Among these alkyl groups, alkyl groups having 1 to 3 carbon atoms, particularly methyl group and / or ethyl group are preferable. The number of substitutions of such an alkyl group is about 1 to 5, preferably about 1 to 3 (for example, 2) for each phenyl group.

In the general formula (I), A represents a phenylene group, such as a 1,3-phenylene group and a 1,4-phenylene group.

Examples of the phenyl group having 1 to 5 alkyl groups having 1 to 4 carbon atoms include 2-methylphenyl group, 3-methylphenyl group, 4-methylphenyl group, 2-ethylphenyl group and 3-ethyl group. Phenyl group, 4-ethylphenyl group, 2-propylphenyl group, 3-propylphenyl group, 4-propylphenyl group, 2-isopropylphenyl group, 3-isopropylphenyl group, 4-isopropylphenyl group, 2-butylphenyl group , 3-butylphenyl group, 4-butylphenyl group, 2-isobutylphenyl group, 3-isobutylphenyl group, 4-isobutylphenyl group, 2-s-butylphenyl group, 3-s-butylphenyl group, 4-s -Butylphenyl group, 2-t-butylphenyl group, 3-t-butylphenyl group, 4-t-butylphenyl group, etc. Alkylphenyl group; 2,3-dimethylphenyl group, 2,3-diethylphenyl group, 2,3-dipropylphenyl group, 2,3-diisopropylphenyl group, 2-ethyl-3-methylphenyl group, 3-ethyl −
2,3-Dialkylphenyl group such as 2-methylphenyl group; 2,4-dimethylphenyl group, 2,4-diethylphenyl group, 2,4-dipropylphenyl group, 2,4-diisopropylphenyl group, 2- Ethyl-4-methylphenyl group,
2,4-Dialkylphenyl group such as 4-ethyl-2-methylphenyl group; 2,5-dimethylphenyl group, 2,5-diethylphenyl group, 2,5-dipropylphenyl group, 2,5
-Diisopropylphenyl group, 2-ethyl-5-methylphenyl group, 5-ethyl-2-methylphenyl group, etc.
2,5-dialkylphenyl group; 2,6-dimethylphenyl group, 2,6-diethylphenyl group, 2,6-dipropylphenyl group, 2,6-diisopropylphenyl group, 2,6-dibutylphenyl group, 2 , 6-diisobutylphenyl group, 2,6
-Di-s-butylphenyl group, 2,6-di-t-butylphenyl group, 2-ethyl-6-methylphenyl group and the like 2,
6-dialkylphenyl group; 3,4-dimethylphenyl group, 3,4-diethylphenyl group, 3,4-dipropylphenyl group, 3,4-diisopropylphenyl group, 3-ethyl-4-methylphenyl group, 4 -Ethyl-3-methylphenyl group and other 3,4-dialkylphenyl groups; 3,5-dimethylphenyl group, 3,5-diethylphenyl group, 3,5-dipropylphenyl group, 3,5-diisopropylphenyl group A 3,5-dialkylphenyl group such as a 3-ethyl-5-methylphenyl group; a 2,3,4-trimethylphenyl group;
2,3,5-trimethylphenyl group, 2,3,6-trimethylphenyl group, 2,4,5-trimethylphenyl group, 2,4,6-trimethylphenyl group, 3,4,5-trimethylphenyl group,
Trialkylphenyl groups such as 4-ethyl-2,6-dimethylphenyl group, 2,6-diethyl-4-methylphenyl group and 4-methyl-2,6-diisopropylphenyl group are included.

Among these, phenyl groups having two alkyl groups having 1 to 3 carbon atoms such as methyl, ethyl and propyl groups (eg, 2,6-dimethylphenyl group, 3,5-dimethylphenyl group, 2, (Dimethylphenyl group such as 4-dimethylphenyl group) and the like are preferable. When a compound having a phenyl group having two alkyl groups having 1 to 3 carbon atoms, particularly a dimethylphenyl group, is used, the heat resistance of the molded product is significantly improved. As the phenyl group having two alkyl groups having 1 to 3 carbon atoms, the alkyl group is 2
In many cases, a phenyl group at the 6- and 6-positions (eg, 2,6-dimethylphenyl group, 2,6-diethylphenyl group, 2-ethyl-6-methylphenyl group, etc.) is used.

The substituents R ^{1 to} R ⁴ are phenyl groups which may have an alkyl group having 1 to ⁴ carbon atoms, and R ^{1 to} R ⁴ may be the same or different. The substituents R ^{1 to} R ⁴ have ^{1 to 4} carbon atoms
When a compound which is a phenyl group having 1 to 5 alkyl groups is used, melt flowability and light resistance of a molded product can be remarkably improved.

In the above general formula (I), the repeating unit n
Is an integer of 1 to 5, but it is preferably an integer of 1 to 3, especially 1 or 2 and particularly 1 because it constitutes a phosphoric acid ester oligomer type flame retardant. The aromatic phosphate ester flame retardant (C) may be used alone or in combination of two or more.

The condensed phosphoric acid ester compound (C) can be prepared by various methods, for example, phenols corresponding to R ¹ , R ² , R ³ and R ⁴ as described in JP-A No. 5-1079. It can be produced by reacting a compound (for example, phenol, cresol, xylenol, etc.) with phosphorus oxychloride and resorcinol.

The organic phosphorus compound (D) in the present invention is represented by the following general formula (II).

[0032]

[Chemical 6]

[In the formula, R ⁵ and R ⁶ are phenyl groups which may have 1 to 3 alkyl groups having 1 to 4 carbon atoms, and R ⁵ and R ^{6 are}
May be the same or different. The (D) organophosphorus compound can be produced by a known method.
For example, according to the method described in US Pat. No. 3,090,799, pentaerythritol and phosphorus oxychloride are reacted as shown in the following formula,

[0034]

[Chemical 7]

Then, as shown in the following formula, it can be produced by reacting the above intermediate product with a monohydric phenol.

[0036]

[Chemical 8]

[In the formula, R represents an aromatic group. In the present invention, R is an alkyl group having 1 to 4 carbon atoms
~ 3 phenyl groups which may have, for example, phenyl, 2-methylphenyl, 4-methylphenyl, 2,6-
Dimethylphenyl, 2,4,6-trimethylphenyl, 2,6
-Di-tert-butylphenyl, 2,4,6-tri-tert-butylphenyl and the like.

In the resin composition of the present invention, the compounding amount of the (C) condensed phosphoric acid ester compound is 100 parts by weight of a thermoplastic resin mixture comprising (A) an aromatic polycarbonate and (B) a styrene resin. , 5 to 50 parts by weight. If the blending amount is less than 5 parts by weight, the flame retardant effect is not sufficient, and if it exceeds 50 parts by weight, the electrical characteristics are deteriorated, which is not preferable.

Further, the compounding amount of the (D) organophosphorus compound is
0.5 to 30 parts by weight per 100 parts by weight of a thermoplastic resin mixture comprising (A) an aromatic polycarbonate and (B) a styrene resin.
Parts by weight. If the blending amount is less than 0.5 part by weight, the synergistic effect of improving flame retardancy due to the combined use with the (C) condensed phosphoric acid ester compound cannot be obtained, and if it exceeds 30 parts by weight, the mechanical strength such as impact resistance is deteriorated. It is not preferable because it significantly decreases.

In the present invention, the compounding ratio of the (C) condensed phosphoric acid ester compound and the (D) organic phosphorus compound is as follows:
The phosphorus concentration ratio (P _D / P _C ) of the (D) organophosphorus compound and the (C) condensed phosphoric acid ester compound in the resin composition is less than 2 (substantially not including 0), preferably 0.1 to 1.9, more preferably 0.5 to 1.0. When the phosphorus concentration ratio (P _D / P _C ) exceeds 2, the synergistic effect of improving the flame retardancy due to the combined use of the (C) condensed phosphoric acid ester compound and the (D) organic phosphorus compound is reduced.

The fluororesin which is the E component of the present invention functions as a flame retardant aid because it suppresses the ignition of the fire and the dropping (drip) of the melt. The fluororesin, for example, tetrafluoroethylene, chlorotrifluoroethylene, vinyl fluoride, vinylidene fluoride, hexafluoropropylene, a homo- or copolymer of fluorine-containing monomers such as perfluoroalkyl vinyl ether and the fluorine-containing monomer, Copolymers with polymerizable monomers such as ethylene, propylene and acrylate are included. Typical examples of the fluororesin include homopolymers such as polytetrafluoroethylene, polychlorotrifluoroethylene, and polyvinylidene fluoride, tetrafluoroethylene-hexafluoropropylene copolymer, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer. Coalescing,
Tetrafluoroethylene-hexafluoropropylene-
Perfluoroalkyl vinyl ether copolymers, ethylene-tetrafluoroethylene copolymers, ethylene-chlorotrifluoroethylene copolymers and the like. These fluororesins can be used alone or in combination of two or more. Among these fluororesins, polytetrafluoroethylene is preferred.

The fluororesin is prepared by a conventional method, for example,
It can be obtained by the emulsion polymerization method described in US Pat. No. 2,393,967.

The fluororesin may be mixed by melt-mixing with an aromatic polycarbonate and a styrene resin, but it is granular, for example, an average particle size of 10 to 5000 μm, preferably 100 to 1000 μm, more preferably 200 to 700. It is often used as a powder or granule of about μm.

(E) The amount of fluororesin used is, for example, (A)
0.05 to 5 parts by weight, preferably 0.1 to 2 parts by weight, more preferably 0.2, based on 100 parts by weight of the thermoplastic resin mixture comprising aromatic polycarbonate and (B) styrene resin.
It is about 1 part by weight. If the amount of fluororesin added is less than 0.05 parts by weight, the drip prevention effect is small and it is difficult to impart high flame retardancy to the molded product. If it exceeds 5 parts by weight, the thermal contraction of the molded product is large, and Not only the dimensional accuracy decreases, but also the cost increases.

The flame-retardant resin composition of the present invention contains various additives, for example, antioxidants, ultraviolet absorbers, deterioration inhibitors such as light stabilizers, lubricants, antistatic agents, release agents and plasticizers. Agents, reinforcing fibers such as glass fibers, carbon fibers, polyamide fibers and polyester fibers, fillers such as calcium carbonate and talc, and coloring agents such as pigments may be added. The amount of the additive used can be appropriately selected according to the type of the additive within a range that does not impair heat resistance, impact resistance, mechanical strength and the like.

[Preparation of flame-retardant resin composition] The flame-retardant resin composition of the present invention comprises (A) an aromatic polycarbonate, (B) a styrene resin, (C) a condensed phosphoric acid ester compound and (D).
It may be a composition prepared by preliminarily mixing an organophosphorus compound and, if necessary, (E) a fluororesin with a mixer such as a V-type blender, a super mixer, a super floater or a Henschel mixer. It is often a mixture in which the mixture is melt-mixed uniformly. Such a mixture can be obtained by melt-kneading the pre-mixture at a temperature of, for example, 200 to 300 ° C, preferably 220 to 280 ° C using a kneading means, and pelletizing. As the kneading means, various melt mixers, for example,
A kneader, a single-screw or twin-screw extruder can be used, but in many cases, the resin composition is melted and extruded using a twin-screw extruder and pelletized by a pelletizer.

The flame-retardant resin composition of the present invention is useful as a material for molding various molded products such as home electric appliances, housings and enclosures of OA equipment, housings and casings of mobile phones and the like. Such a molded article can be produced by a conventional method, for example, by injection-molding a pellet-shaped flame-retardant resin composition using an injection molding machine at a cylinder temperature of about 220 to 280 ° C.

[0048]

The present invention will be described in more detail with reference to the following examples, but the scope of the present invention is not limited to these examples.

The resin compositions of the following Examples and Comparative Examples were evaluated in the following manner.

(1) Heat distortion temperature The heat distortion temperature was 18.6 kg / cm ² on a test piece with a thickness of 1/4 inch.
And was measured according to ASTM D-256.

(2) Izod Impact Strength The Izod impact strength was measured according to ASTM D-256 using a test piece with a cutting notch having a thickness of 1/4 inch.

(3) Flame retardancy Flame retardance was measured using a 1 / 16-inch thick test piece, and as a flame retardancy evaluation scale, a vertical combustion test (94V) specified in UL-94 of the UL standard of the United States was used. -0).

Production Example of Thermoplastic Resin Mixture Polycarbonate resin Tufflon FN2700 (trade name, Idemitsu Petrochemical Co., Ltd., bisphenol A type polycarbonate, viscosity average molecular weight 27,000) (A1), styrene 75 Wt% and acrylonitrile 25
% Of styrene and 45 parts by weight of styrene and 15 parts by weight of acrylonitrile in the presence of a polymer (B1) polymerized by a suspension polymerization method in a calcium phosphate-based dispersant aqueous solution and a polybutadiene rubber latex (40 parts by weight in terms of solid content). And a polymer (B2) graft-polymerized by the emulsion polymerization method are mixed at a ratio of A1 / B1 / B2 = 80/13/7 and 70/20/10 (weight ratio) to prepare a resin mixture. (Each resin mixture was designated as AB-1 and AB-2).

Examples 1 to 4, Comparative Examples 1 to 6 The thermoplastic resin mixture (AB-1, AB-2), (C) PX-200 (trade name, Daihachi Chemical Industry Co., Ltd.) as a condensation type phosphoric acid ester compound (Melting point: 100 ° C), (D) Diphenyl pentaerythritol diphosphate as an organic phosphorus compound (melting point)
197 ° C), (E) Polytetrafluoroethylene as a fluororesin (manufactured by Daikin Industries, Ltd., trade name: Polyflon TF
E, average particle diameter of about 500 μm), antioxidant and heat stabilizer were added, and premixed for 40 minutes with a V-type blender. This preliminary mixture was melt extruded using a twin-screw kneading extruder and pelletized. The above flame retardant PX-200 is represented by the general formula
In (I), R ¹ , R ² , R ³ and R ⁴ are 2,6-dimethylphenyl groups, A is a 1,3-phenylene group, and n = 1
Is a compound of. After drying the obtained pellets in an oven at 80 ° C for 4 hours or more, an injection molding machine (cylinder temperature 2
A test piece for general physical properties was prepared at 50 ° C. and a mold temperature of 60 ° C., and the physical properties were measured according to standard methods. The results are shown in Table 1.

[0055]

[Table 1]

[0056]

EFFECTS OF THE INVENTION By combining a specific phosphorus compound, no corrosive or toxic gas is generated during processing or combustion, excellent flame retardancy, and physical resistance such as heat resistance and impact resistance. It is possible to obtain a polycarbonate-based resin composition that does not deteriorate in properties and does not contain halogen.

─────────────────────────────────────────────────── ─── Continuation of front page (56) Reference JP-A-7-82466 (JP, A) US Patent 5204394 (US, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) C08L 69 / 00

Claims (6)

(57) [Claims] 1. An aromatic polycarbonate, (B) a styrene resin, (C) a condensed phosphoric acid ester compound represented by the following general formula (I), and (D) a general formula (II) below. A resin composition composed of an organic phosphorus compound represented by, and in the resin composition, the phosphorus concentration ratio of the (D) organic phosphorus compound and the (C) condensed phosphoric acid ester compound (P _D / A polycarbonate-based flame-retardant resin composition having a P _C ) of less than 2 (not substantially including 0). [Chemical 1] [In the formula, R ^{1 to} R ⁴ are phenyl groups which may have an alkyl group having 1 to ⁴ carbon atoms, and R ^{1 to} R ⁴ may be the same or different, A is a phenylene group, n represents an integer of 1 to 5. ] [Chemical 2] [In the formula, R ⁵ and R ⁶ are phenyl groups which may have 1 to 3 alkyl groups having 1 to 4 carbon atoms, and R ⁵ and R ⁶ may be the same or different. ] 2. The flame-retardant polycarbonate resin composition according to claim 1, wherein the aromatic polycarbonate (A) is a bisphenol A type aromatic polycarbonate. 3. The polycarbonate-based flame-retardant resin composition according to claim 1, further comprising (E) a fluororesin. 4. The polycarbonate flame-retardant resin composition according to claim 3, wherein the fluororesin (E) is powdery polytetrafluoroethylene. 5. A (C) condensed phosphoric acid based on 100 parts by weight of a thermoplastic resin mixture composed of (A) 40 to 95% by weight of an aromatic polycarbonate and (B) 60 to 5% by weight of a styrene resin. 5 to 50 parts by weight of ester compound, and (D) organophosphorus compound
The polycarbonate flame-retardant resin composition according to claim 1 or 2, which is contained in a proportion of 0.5 to 30 parts by weight. 6. A (C) condensed phosphoric acid based on 100 parts by weight of a thermoplastic resin mixture composed of (A) 40 to 95% by weight of an aromatic polycarbonate and (B) 60 to 5% by weight of a styrene resin. 5 to 50 parts by weight of ester compound, (D) organophosphorus compound 0.5
To 30 parts by weight, and (E) a fluororesin of 0.05 to 5 parts by weight, the polycarbonate flame-retardant resin composition according to claim 3 or 4.