KR20120089737A

KR20120089737A - Polycarbonate resin composition

Info

Publication number: KR20120089737A
Application number: KR1020127013575A
Authority: KR
Inventors: 노리타다 다케우치; 세이이치 젬바
Original assignee: 이데미쓰 고산 가부시키가이샤
Priority date: 2009-11-27
Filing date: 2010-11-11
Publication date: 2012-08-13
Also published as: CN102612543A; TW201125923A; JP2011111560A; WO2011065231A1

Abstract

This invention is thin flame retardance, heat conductivity, which mix | blends 28-90 mass parts of (B) graphite, and 9-20 mass parts of (C) polytetrafluoroethylene with respect to 100 mass parts of (A) aromatic polycarbonate resins, It is a polycarbonate resin composition excellent in mold release property and impact characteristic, and the molded object which consists of it.

Description

Polycarbonate resin composition {POLYCARBONATE RESIN COMPOSITION}

BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a polycarbonate resin composition and a molded article made of the resin composition, and in particular, to a polycarbonate resin composition excellent in moldability such as flame retardancy, thermal conductivity, impact properties, and fluidity or mold release property, and a molded article formed therefrom. will be.

In product development in the field of electronics and electronics, the focus is on heat dissipation measures, such as high pixel size and high speed processing in digital cameras and digital video cameras, miniaturization of projectors, high speed processing in PCs and mobile devices, and LED lighting of various light sources. Was laid.

The countermeasure for constituting a heat dissipation circuit in a metal part has also been taken. In a miniaturized device, since the heat dissipation circuit becomes complicated, a resin material having excellent thermal conductivity and excellent mechanical strength as a casing can be integrated with the resin casing. It is required.

In addition, in a small electronic device, thinning is also required in the casing and the chassis, and accordingly, the flame retardancy in the molded body of thin is also required.

Polycarbonate resins are widely used in casings of electronic devices, and the like. As a method of improving the flame retardancy of polycarbonate resins, halogen-based flame retardants such as halogenated bisphenol A and halogenated polycarbonate oligomers have a flame retardant such as antimony oxide in terms of flame retardant efficiency. Has been used together. However, in recent years, from the viewpoint of safety and impact on the environment during disposal and incineration, a flame retardant method using a flame retardant containing no halogen has been demanded in the market. As such a non-halogen flame retardant, an organophosphorous flame retardant, especially an organic phosphate ester compound, exhibits excellent flame retardancy when blended with a polycarbonate resin composition, and also acts as a plasticizer, but needs to be blended in a relatively large amount. Moreover, since polycarbonate resin has high molding temperature and high melt viscosity, it exists in the tendency for molding temperature to become high. Although phosphate ester compounds generally contribute to flame retardancy, there may be cases in which the phosphate ester compound is not necessarily sufficient in the molding environment and the appearance of the molded article, such as mold corrosion and gas generation during molding. In addition, problems such as a decrease in impact strength and generation of discoloration have been pointed out when the molded article is placed under a high temperature environment.

In addition, the recent demand for recycling aptitude in resource saving has left a problem such that recycling is difficult due to insufficient thermal stability.

Therefore, without using a halogen compound or a phosphate ester compound as a flame retardant, it is desired to find out the polycarbonate resin composition which is excellent in thermal conductivity while achieving the flame retardancy in the molded molded article of thin thickness.

It is known to mix | blend graphite as a means of providing the said heat dissipation property to thermoplastic resins, such as a polycarbonate resin (refer patent document 1, patent document 2). Patent Document 1 discloses that a thermoplastic resin composition having low metal corrosiveness and excellent thermal conductivity is obtained by blending specific graphite with a thermoplastic resin, but in order to improve flame retardancy, organic materials such as halogenated carbonate oligomers and halogenated epoxy compounds are disclosed. It is described that it is preferable to use a halogen flame retardant or a phosphate ester flame retardant, and it does not disclose the technique which does not use a chlorine flame retardant, a bromine flame retardant, and a phosphorus flame retardant.

In addition, Patent Document 2 relates to a heat dissipation casing in which a heating element is accommodated, and there is no description of flame retardancy required for casings such as electronic devices. Flame retardants such as organic bromine flame retardants and phosphorus flame retardants are used as additives blended as necessary. Although it discloses, it does not disclose the technique which does not actively use a chlorine flame retardant, a bromine flame retardant, and a phosphorus flame retardant, and since it does not add a flame retardant and an anti-drip agent in the Example, it is thought that it does not have sufficient flame retardance.

In addition, Patent Literature 3 discloses a flame retardant resin composition comprising a polycarbonate resin, graphite, and an organic sulfonic acid alkali (soil) metal salt as a technique that does not actively use a chlorine flame retardant, a bromine flame retardant, and a phosphorus flame retardant. In the evaluation, only evaluation by a molded article having a thickness of 2.5 mm is made, and sufficient flame retardancy is not obtained at a thickness of about 1.5 mm required for a casing such as an electronic device. Moreover, although it is described in patent document 3 to contain a fluorine-containing anti-dropping agent, it is described that a compounding quantity is 0.01-5 mass parts in order to make a melt dropping prevention effect and a flow characteristic compatible.

Japanese Unexamined Patent Publication No. 2007-31611 Japanese Laid-Open Patent Publication No. 2008-31358 Japanese Laid-Open Patent Publication No. 2006-273931

The present invention is excellent in flame retardancy (thickness 1.2 to 1.0 mm, V-0 to V-1; hereinafter referred to as "thin flame retardancy") in a thin molded body without using a chlorine flame retardant, a bromine flame retardant, and a phosphorus flame retardant, and has high thermal conductivity. It aims at providing the polycarbonate resin composition which has a shock absorbing property, and excellent moldability, such as fluidity | liquidity and mold release property, and its molded object.

MEANS TO SOLVE THE PROBLEM As a result of earnestly researching in order to achieve the said objective, the present inventors mix | blended graphite and polytetrafluoroethylene more than the quantity normally used as an antidropping agent, and it is excellent in thin flame retardance, The polycarbonate resin composition which was excellent also in heat conductivity, impact characteristic, and moldability, such as fluidity | liquidity and mold release property, was found and the present invention was completed.

That is, the present invention,

(1) Polycarbonate resin composition which mix | blends 28-90 mass parts of (B) graphite, and 9-20 mass parts of (C) polytetrafluoroethylene with respect to 100 mass parts of (A) aromatic polycarbonate resins,

(2) The polycarbonate resin composition according to the above (1), further comprising (D) 0.1 to 0.5 parts by mass of an organic alkali (earth) metal salt,

(3) the polycarbonate resin composition according to the above (1) or (2), wherein the graphite is natural graphite;

(4) the polycarbonate resin composition according to the above (1) or (2), wherein the graphite is artificial graphite;

(5) The polycarbonate resin composition according to the above (2), wherein the organic alkali metal salt and / or organic alkaline earth metal salt is at least one member selected from sulfonic acid alkali metal salts, sulfonic acid alkaline earth metal salts, polystyrene sulfonic acid alkali metal salts and polystyrene sulfonic acid alkaline earth metal salts,

(6) The polycarbonate resin composition according to the above (5), wherein the sulfonic acid alkali metal salt is a paratoluene sulfonate sodium salt,

(7) A molded article made of the polycarbonate resin composition according to any one of the above (1) to (6),

(8) The molded article according to the above (7), which is a component for an electric and electronic device,

(9) The molded article according to the above (7), which is a casing for an electric and electronic device,

(10) The molded article according to (7), which is a chassis for electrical and electronic equipment.

To provide.

ADVANTAGE OF THE INVENTION According to this invention, the resin composition and molded object which are excellent in moldability, such as thin flame retardance, heat conductivity, fluidity | liquidity, and mold release property, can be obtained, without impairing the original mechanical property which polycarbonate resin has.

Hereinafter, the present invention will be described in detail.

The polycarbonate resin of the present invention (hereinafter sometimes abbreviated as "PC resin") is a composition comprising (A) aromatic polycarbonate resin, (B) graphite, and (C) polytetrafluoroethylene as essential components. It is a carbonate resin composition.

There is no restriction | limiting in particular as aromatic polycarbonate resin used as (A) component in this invention, Various things are mentioned, Usually, the aromatic polycarbonate manufactured by reaction of a bivalent phenol and a carbonate precursor can be used. Can be. For example, dihydric phenol and a carbonate precursor can be used by the solution method or the melting method, specifically, the thing manufactured by reaction of dihydric phenol and phosgene, and transesterification reaction, such as dihydric phenol and diphenyl carbonate.

Various examples of the dihydric phenol include 2,2-bis (4-hydroxyphenyl) propane [bisphenol A], bis (4-hydroxyphenyl) methane and 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) sulfide, bis (4-hydroxyphenyl) sulfone, bis (4-hydroxyphenyl) sulfoxide, bis (4-hydroxyphenyl) ether, bis (4-hydroxyphenyl) ketone Etc. can be mentioned.

Among these, as a particularly preferable dihydric phenol, bis (hydroxyphenyl) alkane type | system | group, especially bisphenol A is made into a main raw material.

In addition, hydroquinone, resorcin, catechol, etc. are mentioned as bivalent phenol. These dihydric phenols may be used independently, respectively and may mix and use 2 or more types. Moreover, you may use a suitable branching agent with the said dihydric phenol, As this branching agent, a trivalent or more polyhydric phenol, specifically 1,1,1- tris (4-hydroxyphenyl) ethane, (alpha), (alpha) ' , α ''-tris (4-hydroxyphenyl) -1,3,5-triisopropylbenzene, 1- [α-methyl-α- (4'-hydroxyphenyl) ethyl] -4- [α ' , α'-bis (4 ''-hydroxyphenyl) ethyl] benzene, phloroglucine, isatinbis (o-cresol) and the like.

Examples of the carbonate precursor include carbonyl halide, carbonyl ester, haloformate, and the like, and specific examples thereof include phosgene and dihaloformate of dihydric phenol, diphenyl carbonate, dimethyl carbonate and diethyl carbonate. .

As a molecular weight regulator used as a molecular terminal group in PC resin of the said (A) component, what is necessary is just what is normally used for superposition | polymerization of polycarbonate, and various monovalent phenols can be used. Specifically, phenol, p-cresol, p-tert-butylphenol, p-tert-octylphenol, p-cumylphenol, bromophenol, tribromophenol, nonylphenol, etc. are mentioned, for example.

In the PC resin composition of this invention, in addition to the said aromatic PC resin, bifunctional carboxyl, such as the polycarbonate-polyorganosiloxane copolymer which has a polyorganosiloxane part, terephthalic acid, in the range in which the objective of this invention is not impaired. Copolymerization resin, such as polyester-polycarbonate resin obtained by superposing | polymerizing polycarbonate in presence of ester precursors, such as an acid or its ester forming derivative, or other polycarbonate resin can be contained suitably.

Since the said (A) aromatic PC resin used by this invention acquires high impact strength, it is preferable that raw material molecular weight (viscosity average molecular weight) [Mv] is 17,000-30,000. Here, when using natural graphite as (B) graphite demonstrated next, it is preferable from a viewpoint of moldability and impact strength that the said raw material molecular weight (viscosity average molecular weight) [Mv] is 19,000-26,000. When using artificial graphite, it is preferable that it is 18,500-23,000, and when molecular weight is too high, it exists in the tendency for flame retardance to fall easily.

This viscosity average molecular weight (Mv) measures the viscosity of the methylene chloride solution in 20 degreeC using a ubelide-type viscometer, and calculates an intrinsic viscosity [(eta)] from this, and calculates it by following Formula.

[η] = 1.23 × 10 ^-5 Mv ^0.83

Graphite is mix | blended with the polycarbonate resin composition of this invention mainly as (B) component in order to provide thermal conductivity.

As graphite, any of natural graphite or various artificial graphites can be used. As natural graphite, any of earth graphite, impression graphite (Vein Graphite also called block graphite), and flaky graphite (Flake Graphite) can be used. In the natural graphite exemplified above, flaky graphite can be preferably used. By application of natural graphite, higher thermal conductivity and high modulus of elasticity can be obtained.

Artificial graphite heat-treats amorphous carbon to artificially align irregular graphite crystals, and includes not only artificial graphite used for general carbon materials but also kishi graphite, decomposed graphite, pyrolytic graphite, and the like. Artificial graphite used for general carbon materials is usually produced by graphitization treatment using petroleum coke or coal-based pitch coke as a main raw material.

This artificial graphite has a merit that high weld strength can be obtained, although the bending elastic modulus and the thermal conductivity are lower than those of the natural graphite.

The compounding quantity of (B) component needs to be 28-90 mass parts with respect to 100 mass parts of (A) component mentioned above, Preferably it is the range of 30-70 mass parts. If the blending amount is less than 28 parts by mass, sufficient thermal conductivity is hardly obtained, and if it is more than 90 parts by mass, there is a problem that the impact strength is easily lowered. Here, in the case of the resin composition which mix | blended the said natural graphite in the range of 40-60 mass parts, a flame retardance improvement effect becomes remarkable, and flame retardancy evaluation (UL standard 94) in thickness (thickness 1.2mm) can achieve V-0. It becomes possible.

In the present invention, the particle size of the graphite can be preferably used having a 50% cumulative diameter of 30 ~ 180 ㎛. The fixed carbon amount of the graphite is preferably 80% by weight or more, more preferably 90% by weight or more, even more preferably 98% by weight or more. In addition, the volatile matter of the graphite of the present invention is preferably 3% by weight or less, more preferably 1.5% by weight or less, still more preferably 1% by weight or less.

In addition, the surface of the graphite may be treated with a surface treatment such as an epoxy treatment, a urethane treatment, a silane coupling treatment, an oxidation treatment, or the like in order to increase the affinity with the thermoplastic resin as long as the characteristics of the composition of the present invention are not impaired. You may carry out.

(C) polytetrafluoroethylene (PTFE) is mix | blended with the polycarbonate resin composition of this invention in order to improve flame retardance. This (C) component gives a resin dripping prevention effect to the resin composition of this invention, and expresses the outstanding thin flame retardance.

It is preferable that (C) component has fibril formation ability. Here, the "fibril formation ability" means what shows the tendency for resins to couple | bond and become fibrous by external effects, such as a shearing force. As (C) component of this invention, a polytetrafluoroethylene, a tetrafluoroethylene-type copolymer (for example, tetrafluoroethylene / hexafluoropropylene copolymer etc.) etc. are mentioned, for example. Among these, polytetrafluoroethylene is preferable.

PTFE having fibril-forming ability has a very high molecular weight and is a number average molecular weight determined from standard specific gravity, and is usually 500,000 or more, preferably 500,000 to 15 million, and more preferably 1 million to 10 million. Specifically, tetrafluoroethylene is used in an aqueous solvent in the presence of sodium, potassium or ammonium peroxydisulfide under a pressure of about 7 to 700 kPa, at a temperature of about 0 to 200 ° C, preferably at 20 to 100 ° C. It can obtain by superposing | polymerizing.

In addition to the solid form, an aqueous dispersion may also be used, and those classified as Type 3 according to ASTM standards may be used. As a commercial item classified into this type 3, for example, "Teflon 6-J" [brand name, Mitsui Dupont Floro Chemical Co., Ltd.], "polypron D-1", and "polyfron F-103" , Daikin Industries Co., Ltd.], etc. are mentioned. Moreover, other than Type 3, "Algopron F5" (brand name, the product made by Solvay Sollexis Co., Ltd.), "Polyphron MPAFA-100" (brand name, Daikin Industries Co., Ltd. product), etc. are mentioned.

The PTFE may be used alone or in combination of two or more thereof.

The compounding quantity of (C) component needs to be in the range of 9-20 mass parts with respect to 100 mass parts of above-mentioned (A) component, Preferably it is 10-18 mass parts. If the compounding quantity is less than 9 mass parts, it will become impossible to ensure thin flame retardance, and if it exceeds 20 mass parts, the flow characteristic of a molten resin composition will fall and moldability will deteriorate.

This compounding amount is very large compared to the amount of PTFE that is normally formulated as a dropping inhibitor (usually 0.5 mass% or less of the whole PC resin composition), but depending on the range of the compounding amount, the dynamic friction coefficient in addition to the thin flame retardancy decreases. There is an advantage that the release action at the time of molding is improved.

As mentioned above, when the compounding quantity of graphite of the above-mentioned (B) component is 28-90 mass parts with respect to 100 mass parts of (A) component, and 9-20 mass parts of (C) component are mix | blended, it is normally used by PC resin. Even if it does not mix | blend a flame retardant, for example, the following organic alkali (earth) metal salt, flame retardancy evaluation (UL standard 94) in a thin thickness (1.2 mm) can achieve V-1.

In order to further improve the thin flame retardance of the polycarbonate resin composition of the present invention, it is preferable to mix (D) an organic alkali metal salt and / or an organic alkaline earth metal salt.

Examples of the organic alkali metal salts and / or organic alkaline earth metal salts include various types of organic acids having at least one carbon atom, or alkali metal salts and organic alkaline earth metal salts of organic acid esters.

Here, the organic acid or organic acid ester is organic sulfonic acid, organic carboxylic acid or the like. On the other hand, alkali metals are lithium, sodium, potassium, cesium and the like, and alkaline earth metals are magnesium, calcium, strontium, barium and the like, and among these, salts of sodium and potassium are preferably used. The salt of the organic acid may be substituted with halogen such as fluorine, chlorine, and bromine. Alkali metal salt and organic alkaline-earth metal salt can be used individually by 1 type or in combination of 2 or more type.

Among the various organic alkali metal salts and organic alkaline earth metal salts, for example, in the case of organic sulfonic acid, paratoluene sulfonic acid, 2,5-dichlorobenzene sulfonic acid; 2,4,5-trichlorobenzene sulfonic acid; Diphenylsulfone-3-sulfonic acid; Diphenylsulfone-3,3'- disulfonic acid; Alkali metal salts of organic sulfonic acids, such as naphthalene trisulfonic acid, etc. are mentioned.

Moreover, as organic carboxylic acid, for example, perfluoro formic acid, perfluoromethane carboxylic acid, perfluoroethane carboxylic acid, perfluoro propane carboxylic acid, perfluorobutane carboxylic acid, purple Luoromethylbutanecarboxylic acid, perfluorohexane carboxylic acid, perfluoroheptancarboxylic acid, perfluorooctane carboxylic acid, etc. are mentioned, The alkali metal salt of these organic carboxylic acids is used.

Next, as an alkali metal salt and / or alkaline earth metal salt of polystyrene sulfonic acid which can be used for (D) component, the sulfonic acid base containing aromatic vinyl resin represented by following General formula (1) can be used.

[Formula 1]

In said formula (1), Z <^1> shows a sulfonic acid base and Z <^2> represents a hydrogen atom or a C1-C10 hydrocarbon group. g is an integer of 1-5. h represents a mole fraction and 0 <h ≦ 1.

Here, the sulfonic acid base is an alkali metal salt and / or alkaline earth metal salt of sulfonic acid, and examples of the metal include sodium, potassium, lithium, rubidium, cesium, beryllium, magnesium, calcium, strontium and barium.

In formula, Z <^2> is a hydrogen atom or a C1-C10 hydrocarbon group, Preferably it is a hydrogen atom or a methyl group. In addition, g is an integer of 1-5, h is a relationship of 0 <h <= 1. That is, the sulfonic acid base (Z ¹ ) may be completely substituted with or partially substituted with the aromatic ring.

In order to further enhance the effect of thin flame retardancy of the polycarbonate resin composition of the present invention, the substitution ratio of the sulfonic acid base is determined in consideration of the content of the sulfonic acid base-containing aromatic vinyl resin, and the like, and generally 10 to 100% substitution is used. do.

Moreover, in the alkali metal salt and / or alkaline earth metal salt of polystyrene sulfonic acid, the sulfonic acid base containing aromatic vinyl resin is not limited to the polystyrene resin of the said General formula (1), but is copolymer of the other monomer copolymerizable with a styrene monomer. It may be.

Here, as a manufacturing method of a sulfonic acid base containing aromatic vinyl resin, (I) the method of superposing | polymerizing or copolymerizing the aromatic vinyl monomer which has the said sulfonic acid group etc., or another monomer copolymerizable with these, (II) aromatic vinyl polymer Or a copolymer of an aromatic vinyl monomer and another copolymerizable monomer, or a mixed polymer thereof, and a method of sulfonating and neutralizing an alkali metal compound and / or an alkaline earth metal compound.

For example, in the method of the above (II), a polystyrene sulfone oxide is produced by adding a mixed solution of concentrated sulfuric acid and acetic anhydride to a 1,2-dichloroethane solution of a polystyrene resin and heating it for reaction for several hours. Subsequently, potassium polystyrene sulfonate salt or sodium salt can be obtained by neutralizing with sulfonic acid group and sugar molar amount of potassium hydroxide or sodium hydroxide.

As a weight average molecular weight of the sulfonic acid base containing aromatic vinyl type resin used by this invention, it is about 1,000-300,000, Preferably it is about 2,000-200,000.

In addition, a weight average molecular weight can be measured by GPC method.

1 type may be used for the said (D) component, and may be used for it in combination of 2 or more type. Moreover, the content is 0.1-0.5 mass part with respect to 100 mass parts of (A) component, Preferably it is 0.2-0.4 mass part. If the said content is 0.1 mass part or more, the improvement effect of a thin flame retardance can be seen, and a thermal stability can be ensured at 0.5 mass part or less.

In the polycarbonate resin composition of the present invention, for the purpose of moldability, impact resistance, appearance improvement, weather resistance improvement, rigidity improvement, etc., an essential component consisting of the above-mentioned (A) to (C), further formulated as necessary ( In addition to the component D), a phenol-based, phosphorus-based, sulfur-based (E) antioxidant and (F) release agent can be contained.

The amount of the antioxidant (E) is preferably 0.001 to 0.5 parts by mass in the phosphorus antioxidant. At 0.001 parts by mass or more, the thermal stability in the granulation step and the molding step can be maintained, and less than 0.5 parts by mass hardly causes a molecular weight decrease. Moreover, in a phenolic antioxidant, addition of 0.001-0.5 mass part is preferable, and impact strength tends to improve.

(F) The mold release agent is not particularly limited as long as it can be blended with a polycarbonate resin to improve mold release properties during molding. In particular, excellent release properties of organic compounds such as beeswax, glycerin monostearate, glycerin tristearate, pentaerythritol monostearate, pentaerythritol tristearate, pentaerythritol tetrastearate, montan ester wax, and carboxylic acid ester It is used preferably. These are, for example, the "waxy? Golden brand" manufactured by Mickey Chemical Industry Co., Ltd., the "Rikemal S-100A", the "Rikemal SL-900", and the "Rikesta EW-440A" manufactured by Riken Vitamin Co., Ltd. The "Roxyol VPG861" by the Japan company, "Licowax E" by the Clarity Japan company, and the "Roxyol EP-32" by the Kogunis Japan company are mentioned. As for the compounding quantity, 0.001-2 mass parts is preferable.

Moreover, you may contain the additive component compatible with other synthetic resin, an elastomer, and a thermoplastic resin as needed. The additives include antistatic agents, polyamide polyether block copolymers (giving permanent antistatic performance), benzotriazole type or benzophenone type ultraviolet absorbers, hindered amine type light stabilizers (weathering agents), plasticizers, antibacterial agents, compatibilizers and Coloring agents (dyes, pigments) and the like.

There is no restriction | limiting in particular if the compounding quantity of the said arbitrary component is a range in which the characteristic of the polycarbonate resin composition of this invention is maintained.

Next, the manufacturing method of the polycarbonate resin composition of this invention is demonstrated.

The polycarbonate resin composition of this invention mix | blends the said (A)-(C) component and (D) component as needed in the said ratio, and mix | blends various arbitrary components used as needed in a suitable ratio, and knead | mixes it Obtained.

Mixing and kneading | mixing are premixed with the apparatus currently used, for example, a ribbon blender, a drum tumbler, etc., and the method of using a Henschel mixer, a Banbury mixer, a single screw extruder, a twin screw extruder, a multi-screw screw extruder, a cornider, etc. Can be carried out. The heating temperature at the time of kneading | mixing is suitably selected normally in the range of 240-320 degreeC. As this melt-kneading molding, use of an extrusion molding machine, particularly a vented extrusion molding machine, is preferable.

Incidentally, other components other than the polycarbonate resin may be added in advance as melt kneading, that is, as a master batch, with the polycarbonate resin or another thermoplastic resin.

The polycarbonate resin composition of the present invention can produce various molded articles by injection molding method, injection compression molding method, extrusion molding method, blow molding method, press molding method, vacuum molding method and foam molding method using the melt kneading molding machine or the obtained pellet as a raw material. Can be. In particular, the obtained pellets can be suitably used for the production of injection molded articles by injection molding and injection compression molding.

The molded object which consists of a polycarbonate resin composition of this invention is, for example

(1) parts for electrical and electronic equipment such as televisions, radio cassettes, video cameras, video tape recorders, audio players, DVD players, air conditioners, mobile phones, displays, computers, registers, electronic calculators, copiers, printers, facsimiles,

(2) the casing for electrical and electronic equipment described in 1 above;

(3) Chassis for electric and electronic devices described in 1 above.

Etc., it can be used preferably.

Example

Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated more concretely, this invention is not restrict | limited at all by these.

A performance evaluation method and the raw material used are shown next.

[Performance Evaluation Method]

(1) thin flame retardant

The vertical combustion test was done using the test piece (127 mm in length, 12.7 mm in width, 1.2 mm in thickness) manufactured according to UL specification 94. Based on the test result, it evaluated by the grade of UL94 V-0, V-1, or V-2, and set it as V-2out which did not reach V-2.

In addition, UL standard 94 is a method of evaluating flame retardancy from the residual flame time after flame-burning the flame of a burner for 10 second by the test piece of the predetermined | prescribed magnitude | size maintained perpendicularly | vertically.

(2) thermal conductivity

It measured by the hot-disk method using the thermal conductivity measuring apparatus "TPA-501" [Kyoto Electronics Co., Ltd. product].

(3) tensile properties

It measured based on ASTMD638.

(4) bending characteristics

a) bending strength

It measured according to ASTMD790.

b) bending modulus

Using a test piece having a thickness of 4 mm and a length of 130 mm manufactured by an injection molding machine, a three-point bending test was conducted in accordance with ASTM Standard D-790 at a distance of 90 mm between points and a load speed of 20 mm / min. Flexural modulus was calculated from the gradient of the strain curve.

(5) weld characteristics

The test piece was shape | molded so that a weld was possible in the center part of the test piece of length 127mm, width 12.3mm, and thickness 1.2mm, and the weld strength (bending strength) was measured based on ASTMD790.

(6) impact characteristics

a) Notched Izo Impact Strength (IZOD)

The impact strength was measured at the measurement temperature of 23 degreeC based on ASTM specification D-256 using the test piece of thickness 3.2mm (1/8 inch) manufactured with the injection molding machine.

b) Isolation impact strength without notch (IZOD)

c) Charpy (flatwise method) impact strength

The impact strength was measured by the flat-wise method based on JISK7111 using the test piece of thickness 3.2mm (1/8 inch) manufactured with the injection molding machine.

(7) Flow characteristic (flow value)

The solidified flow tester was used and it measured by the load of 100 kg at the temperature of 320 degreeC based on JIS-K7210.

(8) release

According to JIS K7218-A method, the counterpart material was made of SUS304 at normal temperature, the sliding test was performed by surface pressure of 250 kPa, and the speed of 0.5 m / sec, and the dynamic friction coefficient was measured.

[Used raw materials]

(A) component

A-1: Aromatic Polycarbonate Resin [manufactured by Idemitsu Heungsan Co., Ltd., "FN1900A", Mv = 19,500]

A-2: Aromatic Polycarbonate Resin [manufactured by Idemitsu Heungsan Co., Ltd., "FN2200A", Mv = 21,500]

A-3: Aromatic Polycarbonate Resin [manufactured by Idemitsu Heungsan Co., Ltd., "FN2500A", Mv = 24,500]

A-4: Aromatic Polycarbonate Resin [manufactured by Idemitsu Heungsan Co., Ltd., "FN2600A", Mv = 26,000]

(B) component graphite

B-1: Natural graphite ["CB-150" by Nippon Graphite Industry Co., Ltd .; Flaky, particle size distribution 63 µm or less 77-87%, 106 µm or more 5% or less, apparent density 0.2-0.3 g / cm 3, 50% cumulative diameter 31-48 µm, fixed carbon 98 mass% or more, ash content 1 mass% or less , Volatile matter 1 mass% or less]

B-2: Artificial graphite ["PAG-420" by Nippon Graphite Industry Co., Ltd .; Indeterminate, 50% cumulative diameter 30-40 µm (50 µm or more and 50% or less), apparent density 0.29-0.37 g / cm 3, fixed carbon 99.4 mass% or more, ash 0.3 mass% or less, volatile matter 0.3 mass% or less]

(C) Component PTFE

PTFE ["Algopron F5" by Solvay Solesis); Algopron F5 is agglomerated, so once master batched with PC flakes (mixing ratio (mass) PC: PTFE = 90: 10 ~ 80: 20) then blended]

(D) component organic alkali (soil) metal salt

Paratoluene sulfonate sodium salt [manufactured by DAH DIING CHEMICAL INDUSTRY, purity of 93% product, sodium sulfate 3 mass% or less, moisture 5 mass% or less]

(E) Component Other Additives Antioxidant

E-1: Phosphorus antioxidant (diphenylisooctyl phosphite) [ADEKASTAB C, made by ADEKA STAB]

E-2: Phenolic antioxidant (octadecyl-3- (3,5-di-t-butyl-hydroxyphenyl) propionate) ["Irganox1076" by Chiba Japan Co., Ltd.]

(F) Component Other Additives Release Agent

F-1: Stearic acid monoglyceride [Likenmal S-100A manufactured by Riken Vitamin Co., Ltd.]

F-2: Pentaerythritol tetrastearate [Riquesta EW-440A, manufactured by Riken Vitamin Co., Ltd.]

Examples 1-15 and Comparative Examples 1-9

Each component is mixed by the ratio shown to Table 1 and Table 2, and it supplies to a vent type biaxial extrusion molding machine [made by Toshiba Machine Co., Ltd .: TEM35], barrel temperature 300-320 degreeC, screw rotation speed 200-600 rotation, discharge amount 10 It melt-kneaded at -30 kg / hr, and obtained the pellet sample for evaluation.

Using this pellet sample for evaluation, the test piece for each test was produced at the molding resin temperature of 320 degreeC with the injection molding machine, and each test was implemented. The results are shown in Table 1 and Table 2.

The following were proved from Table 1 and Table 2.

In Example 1-Example 15, all the evaluation items are excellent, especially in Example 1-Example 6 which contains the component (A)-(C), even if it does not contain the (D) component of a flame retardant, thickness (thickness 1.2) Mm) A polycarbonate resin composition excellent in flame retardancy, thermal conductivity, bending characteristics, and impact strength is obtained. In Examples 8 to 10, the thin flame retardancy was particularly excellent, and V-0 could be achieved.

In Comparative Example 1 and Comparative Example 7 with little graphite content of (B) component, thermal conductivity falls, and in Comparative Example 2 and Comparative Example 8 with too many component (B), impact characteristic falls. In Comparative Example 3, Comparative Example 5, and Comparative Example 6 in which the PTFE content of the component (C) is low, the thin flame retardancy is lowered. Bad sex

Moreover, from comparison of Example 1, Example 4, and Example 5, and the comparative example 3, by making PTFE of (C) component into the quantity within the range of this invention, a dynamic friction coefficient becomes small and a releasability improves. I understand.

Claims

The polycarbonate resin composition formed by mix | blending 28-90 mass parts of (B) graphite, and 9-20 mass parts of (C) polytetrafluoroethylene with respect to 100 mass parts of (A) aromatic polycarbonate resin.

The method of claim 1,
(D) Polycarbonate resin composition which mix | blends 0.1-0.5 mass part of organic alkali (earth) metal salts.

The method according to claim 1 or 2,
Polycarbonate resin composition in which graphite is natural graphite.

The method according to claim 1 or 2,
Polycarbonate resin composition whose graphite is artificial graphite.

The method of claim 2,
The polycarbonate resin composition in which an organic alkali metal salt and / or an organic alkaline earth metal salt is at least 1 sort (s) chosen from a sulfonic acid alkali metal salt, a sulfonic acid alkaline earth metal salt, a polystyrene sulfonic acid alkali metal salt, and a polystyrene sulfonic acid alkaline earth metal salt.

The method of claim 5, wherein
The polycarbonate resin composition wherein the sulfonic acid alkali metal salt is a paratoluene sulfonate sodium salt.

The molded object which consists of a polycarbonate resin composition in any one of Claims 1-6.

The method of claim 7, wherein
Molded product that is a part for electric and electronic devices.

The method of claim 7, wherein
Molded product which is a casing for electrical and electronic equipment.

The method of claim 7, wherein
Molded product that is a chassis for electrical and electronic devices.