JP2010270180A - Aromatic polycarbonate resin composition and molded article - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an aromatic polycarbonate resin composition giving a product that maintains characteristics inherent to the polycarbonate resin, and has excellent light reflectivity, flame retardancy, impact resistance and thermal stability even in a thin molded article, and good appearance. <P>SOLUTION: The aromatic polycarbonate resin composition comprises 100 parts by mass of an aromatic polycarbonate resin (A) with 3 to 30 parts by mass of a titanium oxide additive (B) prepared by surface-treating titanium oxide with an alumina-based surface treating agent and an organosiloxane surface treating agent, 0.01 to 1.0 part by mass of an aromatic sulfonic acid metal salt compound (C) and 0.01 to 1.5 parts by mass of polyfluoroethylene (D), wherein an aromatic ring of the aromatic sulfonic acid metal salt compound (C) does not includes a substituent, or includes only a 1-4C alkyl group as a substituent; and the aromatic sulfonic acid metal salt compound (C) in an aqueous solution shows a pH of 6.0 to 8.5. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an aromatic polycarbonate resin having improved thermal stability by the combined use of titanium oxide and an aromatic sulfonic acid metal salt having a specific hydrogen ion concentration index range, and improved flame retardancy by blending with polyfluoroethylene. The present invention relates to a composition and an aromatic polycarbonate resin molded body obtained by molding the composition, specifically to a light reflecting member. More specifically, the present invention provides an aromatic polycarbonate resin having excellent light reflectivity, light shielding properties, light resistance, hue, and other optical properties as well as thermal stability and flame retardancy while maintaining the original properties of the polycarbonate resin. The present invention relates to a composition and a molded body thereof.

  Polycarbonate resin is a general-purpose engineering plastic that has excellent transparency, mechanical strength, electrical properties, heat resistance, dimensional stability, etc., so electrical / electronic equipment parts, OA equipment, machine parts, vehicle parts, building parts, It is used in a wide range of fields such as various containers, leisure goods and miscellaneous goods.

  Among these fields of use, thin film transistors (TFTs) and other information display devices such as computers and televisions, such as backlight reflectors for liquid crystal display devices, reflective push switches and reflectors for photoelectric switches, Display devices incorporating reflectors that require a high light reflectance are becoming common.

  These light reflecting members that require a high degree of light reflectivity are resin molded bodies formed by molding a polycarbonate resin composition containing a large amount of fine particles such as titanium oxide in terms of light reflectivity, moldability, and impact strength. Is used.

  On the other hand, in the light reflecting member made of a polycarbonate resin composition, there is a strong demand for flame retardant resin materials, and in order to meet these demands, an aromatic polycarbonate resin, a halogen compound, a phosphorus compound, Many techniques for making flame retardant by blending siloxane compounds, polyfluoroethylene and the like have been proposed. Recently, in consideration of the environment, a flame retardant resin composition using another flame retardant without using a brominated flame retardant or a phosphorus flame retardant has been desired.

  For example, Patent Document 1 describes a resin composition obtained by blending polycarbonate resin with aromatic sodium sulfonate as a flame retardant and polytetrafluoroethylene. However, in Patent Document 1, since there is no addition of titanium oxide, the reflection characteristics and the flame retardance with a thin wall are inferior, and thus it cannot be said that it is sufficient as a flame retardant light reflecting material.

  Patent Document 2 discloses an aromatic sulfonic acid metal salt (specifically, a branched sodium dodecylbenzenesulfonate) (B) and polytetrafluoroethylene having a pH of 6.4 to 7.5 in the polycarbonate resin (A). It describes about the resin composition which mix | blended. However, even in this Patent Document 2, since there is no addition of titanium oxide, the flammability at a thickness of less than 1.5 mm does not become V-0 and is not suitable for thin-walled applications.

  On the other hand, Patent Documents 3 and 4 are given as examples of the flame retardant polycarbonate resin composition in which an organic metal salt and titanium oxide are used in combination, but none of them has sufficient performance as described below. .

  That is, Patent Document 3 describes a resin composition obtained by adding (B) titanium oxide and (C) alkylbenzene sulfonic acid antistatic agent 1 to 8 parts by weight (parts by mass) to (A) polycarbonate resin. Yes. However, in this patent document 3, since there is much addition amount of an alkali metal salt, the molecular weight fall of a polycarbonate resin composition is large at the time of shaping | molding, and a moldability and a flame retardance performance fall.

  Patent Document 4 discloses a resin composition in which polytetrafluoroethylene (B), an organic metal salt (E), a silicone compound (D), and a specific titanium oxide (C) are added to a polycarbonate resin (A). Are listed. However, in this patent document 4, the appearance defect such as silver streak largely depends on the state of secondary aggregation of titanium oxide, and satisfactory results cannot be obtained with the titanium oxide described in the claims. Further, the addition of the silicone compound tends to cause poor appearance.

JP 2000-239509 A JP 2007-119554 A JP-A-11-181267 JP 2006-241262 A

  The object of the present invention is to maintain the original characteristics of a polycarbonate resin, and to produce a product having a good appearance even if it is a thin molded article, excellent in light reflectivity, flame retardancy, impact resistance, and thermal stability. An object of the present invention is to provide a polycarbonate resin composition to be obtained and a resin molded body obtained by molding the polycarbonate resin composition, specifically, a light reflecting member.

  In order to solve the above-mentioned problems, the present inventors diligently studied the blending components of the aromatic polycarbonate resin composition. And paying attention to the hydrogen ion concentration index of aromatic sulfonic acid metal salt as flame retardant, while controlling this value, by combining titanium oxide and polyfluoroethylene, light reflectance, flame retardancy The present inventors have found that molded articles such as an aromatic polycarbonate resin composition and a light reflecting member that are excellent in impact resistance and thermal stability and have a good appearance can be obtained.

  That is, the gist of the present invention is that a titanium oxide-based additive (B) obtained by surface-treating titanium oxide with an alumina-based surface treating agent and an organosiloxane-based surface treating agent with respect to 100 parts by mass of the aromatic polycarbonate resin (A). Comprising 3 to 30 parts by mass, 0.01 to 1.0 part by mass of an aromatic sulfonic acid metal salt compound (C), and 0.01 to 1.5 parts by mass of polyfluoroethylene (D), The aromatic ring of the aromatic sulfonic acid metal salt compound (C) does not have a substituent or has only an alkyl group having 1 to 4 carbon atoms as a substituent, and the aromatic sulfonic acid metal salt compound (C ) In an aqueous solution is 6.0 to 8.5, and a molded article obtained from the aromatic polycarbonate resin composition.

  The aromatic polycarbonate resin composition of the present invention is excellent in light resistance, light shielding properties, light reflectivity, hue, flame retardancy, molding stability, and in addition, impact resistance, heat resistance, dimensions inherent in aromatic polycarbonate resins. At the same time, stability and appearance characteristics are maintained. Therefore, the molded product of the present invention formed by molding the aromatic polycarbonate resin composition of the present invention takes advantage of these features to provide a light reflecting plate, a light reflecting frame or a light reflecting sheet for a backlight of a liquid crystal display device, -It can be widely used as a light reflection member for electronic devices, lighting devices such as advertising lights, and automotive devices such as automotive meter panels.

  Hereinafter, embodiments of the present invention will be described in detail.

[Aromatic polycarbonate resin composition]
The aromatic polycarbonate resin composition of the present invention is a titanium oxide-based additive obtained by surface-treating titanium oxide with an alumina-based surface treatment agent and an organosiloxane-based surface treatment agent with respect to 100 parts by mass of the aromatic polycarbonate resin (A). (B) 3-30 parts by mass, 0.01-1.0 parts by mass of aromatic sulfonic acid metal salt compound (C) and 0.01-1.5 parts by mass of polyfluoroethylene (D) The aromatic ring of the aromatic sulfonic acid metal salt compound (C) does not have a substituent or has only an alkyl group having 1 to 4 carbon atoms as a substituent, and the aromatic sulfonic acid metal salt The pH of the compound (C) in an aqueous solution is 6.0 to 8.5.

<Aromatic polycarbonate resin (A)>
The aromatic polycarbonate resin (A) used in the present invention is a thermoplastic heavy chain which may be branched, obtained by reacting an aromatic dihydroxy compound or a small amount thereof with phosgene or a carbonic acid diester. It is a coalescence or copolymer. The production method of the aromatic polycarbonate resin is not particularly limited, and those produced by a conventionally known phosgene method (interfacial polymerization method) or melting method (transesterification method) can be used. Further, when the melting method is used, a polycarbonate resin in which the amount of OH groups of terminal groups is adjusted can be used.

  As the raw material aromatic dihydroxy compound, 2,2-bis (4-hydroxyphenyl) propane (= bisphenol A), tetramethylbisphenol A, bis (4-hydroxyphenyl) -p-diisopropylbenzene, hydroquinone, resorcinol, 4 , 4-dihydroxydiphenyl and the like, preferably bisphenol A. In addition, a compound in which one or more tetraalkylphosphonium sulfonates are bonded to the above aromatic dihydroxy compound can also be used. These aromatic dihydroxy compounds may be used individually by 1 type, and 2 or more types may be mixed and used for them.

  In order to obtain a branched aromatic polycarbonate resin, a part of the above-mentioned aromatic dihydroxy compound is mixed with the following branching agents, that is, phloroglucin, 4,6-dimethyl-2,4,6-tri (4-hydroxyphenyl). Heptene-2,4,6-dimethyl-2,4,6-tri (4-hydroxyphenyl) heptane, 2,6-dimethyl-2,4,6-tri (4-hydroxyphenylheptene-3,1, Polyhydroxy compounds such as 3,5-tri (4-hydroxyphenyl) benzene and 1,1,1-tri (4-hydroxyphenyl) ethane, and 3,3-bis (4-hydroxyaryl) oxindole (= isa) Chin bisphenol), 5-chloruisatin, 5,7-dichlorouisatin, 5-bromoisatin, etc. These branching agents are one kind. These branching agents may be used alone or in a mixture of two or more, and the amount of the branching agent used is 0.01 to 10 mol%, preferably 0, based on the aromatic dihydroxy compound. .1 to 2 mol%.

  In order to adjust the molecular weight of the aromatic polycarbonate resin, a monovalent aromatic hydroxy compound may be used. Examples of the monovalent aromatic hydroxy compound for adjusting the molecular weight include m- and p-methylphenol. , M- and p-propylphenol, p-tert-butylphenol, p-long chain alkyl-substituted phenol, and the like. These may be used alone or in combination of two or more.

  As aromatic polycarbonate resin (A), among the above-mentioned, polycarbonate resin derived from 2,2-bis (4-hydroxyphenyl) propane, or 2,2-bis (4-hydroxyphenyl) propane and other Polycarbonate copolymers derived from aromatic dihydroxy compounds are preferred. Further, it may be a copolymer mainly composed of a polycarbonate resin, such as a copolymer with a polymer or oligomer having a siloxane structure.

  The aromatic polycarbonate resin mentioned above may be used individually by 1 type, and 2 or more types may be mixed and used for it.

The molecular weight of the aromatic polycarbonate resin (A) used in the present invention is arbitrary depending on its use and may be appropriately selected and determined. From the viewpoint of moldability, strength, etc., the molecular weight of the aromatic polycarbonate resin (A) Is a viscosity average molecular weight [Mv] converted from the solution viscosity measured at a temperature of 25 ° C. using methylene chloride as a solvent, and preferably 10,000 to 40,000, more preferably 10,000 to 30,000. As described above, when the viscosity average molecular weight is 10,000 or more, the mechanical strength tends to be further improved, and the viscosity average molecular weight is more preferable when used for an application requiring high mechanical strength. On the other hand, by setting the viscosity average molecular weight to 40000 or less, there is a tendency to further suppress and improve fluidity reduction, which is more preferable from the viewpoint of easy molding processability.
Among them, the viscosity average molecular weight of the aromatic polycarbonate resin (A) is preferably 10,000 to 22,000, more preferably 12,000 to 22,000, and particularly preferably 14,000 to 20,000.

  In addition, you may mix and use 2 or more types of aromatic polycarbonate resin from which a viscosity average molecular weight differs, In this case, you may mix the aromatic polycarbonate resin whose viscosity average molecular weight is outside the said suitable range. In this case, the viscosity average molecular weight of the mixture is preferably within the above range.

<Titanium oxide-based additive (B)>
The titanium oxide-based additive (B) in the present invention is obtained by surface-treating titanium oxide with an alumina-based surface treatment agent and an organosiloxane-based surface treatment agent, and is a molded product obtained from the aromatic polycarbonate resin composition of the present invention. It functions to improve the light shielding properties, whiteness, light reflection characteristics, etc.

  The production method, crystal form, average particle size, and the like of titanium oxide used for the titanium oxide-based additive (B) are not particularly limited, but are preferably as follows.

  There are sulfuric acid method and chlorine method in the production method of titanium oxide, but titanium oxide produced by sulfuric acid method tends to be inferior in whiteness of the composition to which this is added, so the object of the present invention is effective. In order to achieve the above, those produced by the chlorine method are preferred.

  Further, the crystal form of titanium oxide includes a rutile type and an anatase type, but a rutile type crystal form is preferable from the viewpoint of light resistance.

The average particle diameter of the titanium oxide constituting the titanium oxide-based additive (B) is usually 0.1 to 0.7 μm, preferably 0.1 to 0.4 μm. When the average particle diameter of titanium oxide is less than 0.1 μm, the resulting molded article has poor light shielding properties. When it exceeds 0.7 μm, the surface of the molded article is roughened, and the mechanical strength of the molded article is reduced. Or Here, the average particle diameter of titanium oxide is an average value of primary particle diameters measured and observed by a transmission electron microscope (TEM).
In the present invention, two or more types of titanium oxide having different average particle diameters may be mixed and used.

  The titanium oxide-based additive (B) used in the present invention is obtained by surface-treating titanium oxide with an alumina-based surface treatment agent and an organosiloxane-based surface treatment agent. It is preferable that the surface treatment is performed with the organosiloxane surface treatment agent described later after the pretreatment with the system surface treatment agent and the silicic acid surface treatment agent. Titanium oxide pretreated with an alumina surface treatment agent and, if necessary, a silicic acid surface treatment agent is further surface treated with an organosiloxane surface treatment agent, greatly improving thermal stability. In addition, it is possible to improve the uniform dispersibility and stability of the dispersed state in the aromatic polycarbonate resin composition.

  Here, alumina hydrate is preferably used as the alumina-based surface treatment agent. As the silicic acid-based surface treatment agent, silicic acid hydrate is preferably used. The pretreatment method is not particularly limited, and any method can be used. Pretreatment with an alumina-based surface treatment agent such as alumina hydrate and, if necessary, a silicic acid-based surface treatment agent such as silicic acid hydrate is preferably performed in a range of 1 to 15% by mass with respect to titanium oxide. . That is, when the pretreatment is performed only with the alumina-based surface treatment agent, the alumina-based surface treatment agent is preferably used in an amount of 1 to 15% by mass with respect to the titanium oxide-based additive. When using a silicic acid system surface treating agent together, it is preferable to carry out using these so that these may become 1-15 mass% with respect to a titanium oxide type additive. In addition, when using together an alumina type surface treating agent and a silicic acid type surface treating agent, the use ratio is 35-90 mass of silicic acid type surface treating agents with respect to the sum of an alumina type surface treating agent and a silicic acid type surface treating agent. It is preferable that the amount be about%.

  On the other hand, a polyorganohydrogensiloxane compound is preferably used as the organosiloxane surface treating agent.

Surface treatment methods using an organosiloxane surface treatment agent for titanium oxide include a wet method and a dry method.
The wet method is a method in which a pretreated titanium oxide is added to a mixed liquid of an organosiloxane surface treating agent and a solvent, and after stirring, the solvent is removed, followed by heat treatment at 100 to 300 ° C. The dry method is a method in which pretreated titanium oxide and an organosiloxane surface treatment agent are mixed with a Henschel mixer or the like, and an organic solvent of an organosiloxane surface treatment agent is sprayed on and adhered to the pretreated titanium oxide, The method of heat-processing at 100-300 degreeC etc. are mentioned.

  The degree of surface treatment of the pretreated titanium oxide-based additive with the organosiloxane surface treatment agent is not particularly limited, but considering the reflectivity of titanium oxide, the moldability of the resulting resin composition, etc. The amount of the organosiloxane surface treatment agent for titanium oxide is usually in the range of 1 to 5% by mass.

  Among these, it is preferable that the titanium oxide-based additive (B) used in the present invention has the following physical properties because it exhibits excellent effects in improving thermal stability, flame retardancy, and light reflectivity.

An aluminum content a (mass%) in the titanium oxide additive (B) obtained by fluorescent X-ray analysis of the titanium oxide additive (B) and the titanium oxide additive (B) at high frequency Carbon amount c (mass%) in the titanium oxide-based additive obtained by analysis using a combustion-type carbon analyzer, and the average particle diameter d (μm) of titanium oxide in the titanium oxide-based additive (B) Satisfies the following (formula 1) and (formula 2).
(Formula 1) 6.5 ≦ (a / d ² ) ≦ 15
(Formula 2) 5 ≦ (c / d ² ) ≦ 25

Furthermore the value of (c / d ²⁾ in order to obtain a good thermal stability is preferably the value of (formula 1) (a / d ²⁾ is 8 or more, (Equation 2) is preferably It is less than 20, more preferably less than 15.

The average particle size and surface area of titanium oxide are correlated, and the surface area increases as the average particle size decreases. In the present invention, an excellent light reflectivity can be obtained by using a titanium oxide having a relatively small average particle diameter, that is, a fine particle diameter, and dispersing an appropriate amount of aluminum or the like on the surface of the titanium oxide having a small particle diameter. . (A / d ² ) in (Formula 1) represents the amount of aluminum contained in the alumina-based surface treatment agent relative to the unit surface area of titanium oxide, and (c / d ² ) in (Formula 2) represents the titanium oxide. This represents the amount of organic carbon contained in the organosiloxane surface treatment agent per unit surface area.
When (Formula 1) and (Formula 2) satisfy the above ranges, the surface treatment for titanium oxide becomes appropriate, and a polycarbonate resin composition excellent in thermal stability, flame retardancy, and light reflectivity can be obtained. Become.

When the value of (a / d ²⁾ is less than 6.5, becomes insufficient dispersion of titanium oxide in the composition, no satisfactory molded article occurred easily appearance and reflectivity secondary aggregation is obtained. Moreover, since the basicity of a titanium oxide particle will increase more by the process by an alumina type surface treating agent when it exceeds 15, the thermal stability of a resin composition may fall and it may be inferior to impact property and shaping | molding stability. When the value of (c / d ² ) is less than 5, the surface activity of titanium oxide and the activity of titanium oxide particles imparted with basicity by an alumina surface treatment agent cannot be sufficiently covered. Stability and adhesion may be reduced, and impact and molding stability may be inferior. On the other hand, if it exceeds 25, the organosiloxane surface treatment agent that is not chemically bonded to titanium oxide tends to volatilize during molding, causing mold contamination.

  In this invention, the compounding quantity of a titanium oxide type additive (B) is the range of 3-30 mass parts with respect to 100 mass parts of aromatic polycarbonate resin (A). When the blending amount of the titanium oxide-based additive (B) is less than 3 parts by mass, the resulting molded article has insufficient light shielding properties and reflection characteristics, and when it exceeds 30 parts by mass, the impact resistance is insufficient. . The preferable compounding quantity of a titanium oxide type additive (B) is 3-25 mass parts with respect to 100 mass parts of aromatic polycarbonate resin, More preferably, it is 5-20 mass parts. In addition, the mass of the titanium oxide-based additive (B) means a mass including an alumina-based, silicic acid-based, and organosiloxane-based surface treatment agent that has been surface-treated with titanium oxide.

<Aromatic sulfonic acid metal salt compound (C)>
The aromatic sulfonic acid metal salt compound (C) used in the present invention functions as a flame retardant for improving the flame retardancy of the aromatic polycarbonate resin, and the aromatic sulfonic acid metal salt compound (C) The aromatic ring does not have a substituent or has only an alkyl group having 1 to 4 carbon atoms as a substituent, and the pH (hydrogen ion concentration) of the aromatic sulfonic acid metal salt compound (C) in an aqueous solution The index) is 6.0 to 8.5, preferably 6.5 to 8.0.
In addition, the aromatic ring of the aromatic sulfonic acid metal salt compound (C) is not limited to a single ring, and may be a bonded ring in which two or more aromatic rings are bonded. In addition, the aromatic sulfonic acid metal salt compound (C) is not limited to having only one aromatic ring, but may have two or more. Moreover, the aromatic sulfonic acid metal salt compound (C) in the present invention includes an aromatic sulfonic acid metal salt compound and a derivative thereof.

  Here, the pH in the aqueous solution of the aromatic sulfonic acid metal salt compound (C) refers to the pH at 23 ° C. of the 10% by mass aqueous solution of the aromatic sulfonic acid metal salt compound (C). It is measured with a meter.

  When the pH of the aromatic sulfonic acid metal salt compound (C) is less than 6.0, the reaction activity between the aromatic sulfonic acid metal salt compound (C) and the aromatic polycarbonate resin decreases during combustion, and thus flame retardant. When the pH is more than 8.5, the decomposition reaction of the aromatic polycarbonate resin by the aromatic sulfonic acid metal salt compound (C) greatly proceeds, so that the flame retardancy and thermal stability are inferior.

  The aromatic ring of the aromatic sulfonic acid metal salt compound (C) has no substituent, or when the substituent is bonded, the substituent is an alkyl group having 1 to 4 carbon atoms (methyl group). , Ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group). In the aromatic sulfonic acid metal salt compound (C) having an alkyl group having 5 or more carbon atoms and other substituents on the aromatic ring, the flame retardancy is lowered due to the influence of the aliphatic groups and other substituents. In addition, if a substituent is a C1-C4 alkyl group, you may substitute 2 or more by one aromatic ring.

  The metal of the aromatic sulfonic acid metal salt compound (C) is preferably an alkali metal or an alkaline earth metal. Examples of the alkali metal and alkaline earth metal include sodium, lithium, potassium, rubidium, cesium, beryllium, magnesium, calcium, strontium, and barium. Among them, sodium and potassium are preferable as the alkali metal, and magnesium, calcium and cesium are preferable as the alkaline earth metal from the viewpoint of compatibility with the polycarbonate resin and imparting flame retardancy.

Examples of aromatic sulfonic acid metal salt compounds (C) include diphenylsulfone-3-sulfonic acid sodium salt, diphenylsulfone-3-sulfonic acid potassium salt, diphenylsulfone-3,3′-disulfonic acid disodium salt, diphenylsulfone -3,3'-disulfonic acid dipotassium salt. Among these, paratoluenesulfonic acid sodium salt or paratoluenesulfonic acid potassium salt is preferably used from the viewpoints of flame retardancy, thermal stability, and handleability.
These aromatic sulfonic acid metal salt compounds (C) may be used singly or in combination of two or more.

  In this invention, the compounding quantity of an aromatic sulfonic acid metal salt compound (C) is 0.01-1.0 mass part with respect to 100 mass parts of aromatic polycarbonate resin composition (A). If the blending amount is less than 0.01 parts by mass, the effect of improving flame retardancy is insufficient, and if it exceeds 1.0 parts by mass, the thermal stability during molding of the aromatic polycarbonate resin composition and the physical properties in the wet heat test are May decrease. Especially, an aromatic sulfonic acid metal salt compound (C) is 0.03-0.8 mass part with respect to 100 mass parts of aromatic polycarbonate resin (A), Especially in the range of 0.05-0.6 mass part. It is preferable to be used.

<Polyfluoroethylene (D)>
In the present invention, the polyfluoroethylene (D) is preferably polytetrafluoroethylene having fibril forming ability. Polytetrafluoroethylene having fibril-forming ability is classified as type 3 according to the ASTM standard. Examples of polytetrafluoroethylene having fibril-forming ability include Teflon (registered trademark) 6J manufactured by Mitsui / Dupont Fluorochemical, and Polyflon F201L, FA500B, and FA500C manufactured by Daikin Chemical Industries. Examples of the aqueous dispersion of polytetrafluoroethylene include Fluon D-1 manufactured by Daikin Chemical Industries, Ltd. and polyfluoroethylene compounds having a multilayer structure formed by polymerizing vinyl monomers. Any type can be used for the resin composition of this invention, and these may be used individually by 1 type and may be used in mixture of 2 or more types.

  In order to further improve the appearance of a molded article obtained by injection molding a flame retardant resin composition containing polyfluoroethylene, a specific coated polyfluoroethylene (hereinafter referred to as “coated polyfluoroethylene”) coated with an organic polymer is used. Can be abbreviated as ")". This coated polyfluoroethylene has a polyfluoroethylene content in the coated polyfluoroethylene in the range of 40 to 95% by mass, particularly 43 to 80% by mass, more preferably 45 to 70% by mass, and particularly 47 to 60% by mass. % Is preferable. As such a coated polyfluoroethylene, for example, Metablene A-3800, A-3700, KA-5503 manufactured by Mitsubishi Rayon Co., Poly TS AD001 manufactured by PIC Co., etc. can be used.

  In this invention, the compounding quantity of polyfluoroethylene (D) is 0.01-1.5 mass parts with respect to 100 mass parts of aromatic polycarbonate resin (A), 0.05-0.9 mass part is Preferably, 0.1-0.7 mass part is especially preferable. In the case of coated polyfluoroethylene, the blending amount corresponds to the amount of pure polyfluoroethylene. When the blending amount of polyfluoroethylene (D) is less than 0.01 parts by mass, flame retardancy may be reduced. On the other hand, when it exceeds 1.5 parts by mass, the appearance of the molded article may be deteriorated. is there.

<Other ingredients>
To the aromatic polycarbonate resin composition of the present invention, if necessary, in addition to the above-described components, in addition to the above-described components, other resins other than the aromatic polycarbonate resin and various resin additions may be added. An agent or the like may be used.

  Examples of other resins include polyolefin resins such as polyethylene resins and polypropylene resins, polyamide resins, polyimide resins, polyetherimide resins, polyurethane resins, polyphenylene ether resins, polyphenylene sulfide resins, polysulfone resins, polymethacrylate resins, and polyester resins. And acrylonitrile-styrene-butadiene copolymer resin (ABS). Further, polycarbonate resins other than aromatic polycarbonate resins may be used. These may be used alone or in combination of two or more.

  When a resin other than the aromatic polycarbonate resin is used for the aromatic polycarbonate resin composition of the present invention, the blending amount thereof is the sum of the aromatic polycarbonate resin and the other resin in order not to impair the characteristics of the aromatic polycarbonate resin. On the other hand, it is preferably 30% by mass or less.

Resin additives include impact resistance improvers, mold release agents, dyes and pigments, flame retardants, antistatic agents, antifogging agents, lubricants / antiblocking agents, fluidity improvers, plasticizers, dispersants, anti-proofing agents. Examples include fungicides, fluorescent brighteners, and UV absorbers.
Furthermore, as inorganic resin additives, glass fiber, glass milled fiber, glass flake, glass bead, carbon fiber, silica, alumina, calcium sulfate powder, gypsum, gypsum whisker, barium sulfate, talc, mica, calcium silicate, carbon Examples thereof include inorganic fillers such as black and graphite. These may be used alone or in combination of two or more.

(Thermal stabilizer / antioxidant)
The aromatic polycarbonate resin composition of the present invention contains a thermal stabilizer and an antioxidant for the purpose of suppressing yellowing that occurs during melt processing and when used for a long period of time at a high temperature, and further suppressing mechanical strength reduction. It is preferable to contain.

  As the heat stabilizer and the antioxidant, any conventionally known one can be used. As the heat stabilizer, a phosphorus compound is preferable, and as the antioxidant, a phenol compound is preferable, and these may be used in combination.

  Phosphorus compounds are generally effective in improving the residence stability at high temperatures and heat stability when using resin moldings when melt-kneading polycarbonate resins, and phenol compounds are generally effective in heat aging resistance, etc. The heat resistance stability when using the polycarbonate resin molded body is high. In addition, the combined use of the phosphorus compound and the phenol compound further improves the effect of improving the colorability.

  Examples of the phosphorus compound used in the present invention include phosphorous acid, phosphoric acid, phosphite ester, phosphate ester, etc. Among them, phosphite contains trivalent phosphorus and easily exhibits a discoloration suppressing effect. Phosphites such as phosphonite and acid phosphate are preferred.

  Specific examples of the phosphite include triphenyl phosphite, tris (nonylphenyl) phosphite, dilauryl hydrogen phosphite, triethyl phosphite, tridecyl phosphite, tris (2-ethylhexyl) phosphite, and tris. (Tridecyl) phosphite, tristearyl phosphite, diphenyl monodecyl phosphite, monophenyl didecyl phosphite, diphenyl mono (tridecyl) phosphite, tetraphenyl dipropylene glycol diphosphite, tetraphenyl tetra (tridecyl) pentaerythritol tetra Phosphite, hydrogenated bisphenol A phenol phosphite polymer, diphenyl hydrogen phosphite, 4,4′-butylidene-bis (3-methyl-6-t rt-butylphenyldi (tridecyl) phosphite) tetra (tridecyl), 4,4'-isopropylidenediphenyldiphosphite, bis (tridecyl) pentaerythritol diphosphite, bis (nonylphenyl) pentaerythritol diphosphite, di Lauryl pentaerythritol diphosphite, distearyl pentaerythritol diphosphite, tris (4-tert-butylphenyl) phosphite, tris (2,4-di-tert-butylphenyl) phosphite, hydrogenated bisphenol A pentaerythritol phosphite Phytopolymer, bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite, bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite Phosphite, 2,2'-methylenebis (4,6-di -tert- butylphenyl) octyl phosphite, bis (2,4-dicumylphenyl) pentaerythritol diphosphite and the like.

  Examples of phosphonites include tetrakis (2,4-di-iso-propylphenyl) -4,4′-biphenylenediphosphonite, tetrakis (2,4-di-n-butylphenyl) -4,4′-biphenyl. Range phosphonite, tetrakis (2,4-di-tert-butylphenyl) -4,4'-biphenylene diphosphonite, tetrakis (2,4-di-tert-butylphenyl) -4,3'-biphenylene diphospho Knight, tetrakis (2,4-di-tert-butylphenyl) -3,3'-biphenylenediphosphonite, tetrakis (2,6-di-iso-propylphenyl) -4,4'-biphenylenediphosphonite, Tetrakis (2,6-di-n-butylphenyl) -4,4′-biphenylenediphosphonite, tetrakis (2,6- -Tert-butylphenyl) -4,4'-biphenylenediphosphonite, tetrakis (2,6-di-tert-butylphenyl) -4,3'-biphenylenediphosphonite, tetrakis (2,6-di-tert) -Butylphenyl) -3,3'-biphenylenediphosphonite and the like.

  Examples of the acid phosphate include methyl acid phosphate, ethyl acid phosphate, propyl acid phosphate, isopropyl acid phosphate, butyl acid phosphate, butoxyethyl acid phosphate, octyl acid phosphate, 2-ethylhexyl acid phosphate, decyl acid phosphate, and lauryl phosphate. Phosphate, stearyl acid phosphate, oleyl acid phosphate, behenyl acid phosphate, phenyl acid phosphate, nonyl phenyl acid phosphate, cyclohexyl acid phosphate, phenoxyethyl acid phosphate, alkoxy polyethylene glycol acid phosphate, bisphenol A acid Sulfate, dimethyl acid phosphate, diethyl acid phosphate, dipropyl acid phosphate, diisopropyl acid phosphate, dibutyl acid phosphate, dioctyl acid phosphate, di-2-ethylhexyl acid phosphate, dioctyl acid phosphate, dilauryl acid phosphate, distearyl acid phenyl Acid phosphate, bisnonylphenyl acid phosphate, etc. are mentioned.

  Among the phosphites, distearyl pentaerythritol diphosphite, tris (2,4-di-tert-butylphenyl) phosphite, bis (2,6-di-tert-butyl-4-methylphenyl) penta Erythritol diphosphite, 2,2′-methylenebis (4,6-di-tert-butylphenyl) octyl phosphite, bis (2,4-dicumylphenyl) pentaerythritol diphosphite are preferable, and heat resistance is good. Tris (2,4-di-tert-butylphenyl) phosphite is particularly preferred in that it is difficult to hydrolyze.

  As the antioxidant, a phenol compound having a specific structure in the molecule is preferable. Specifically, 2,2′-methylenebis (4-methyl-6-tert-butylphenol), 4,4′-butylidenebis (6-tert- Butyl-3-methylphenol), 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, 3,9-bis [2- {3- (3-tert-butyl) -4-hydroxy-5-methylphenyl) propionyloxy} -1,1-dimethylethyl] -2,4,8,10-tetraoxaspiro [5.5] undecane, triethylene glycol bis [β- (3- tert-butyl-4-hydroxy-5-methylphenyl) propionate], 1,6-hexanediol bis [β- (3-tert-butyl-4 -Hydroxy-5-methylphenyl) propionate], pentaerythritol-tetrakis [β- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionate], octadecyl [β- (3-tert-butyl-4- Hydroxy-5-methylphenyl) propionate] and the like.

  Among these, 4,4′-butylidenebis (6-tert-butyl-3-methylphenol), 1,1,3-tris (2-methyl-4-) is preferred in terms of suppressing yellowing when kneaded with a polycarbonate resin. Hydroxy-5-tert-butylphenyl) butane, 3,9-bis [2- {3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy} -1,1-dimethylethyl]- 2,4,8,10-Tetraoxaspiro [5.5] undecane is preferred, especially 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, 3,9 -Bis [2- {3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy} -1,1-dimethylethyl] -2,4,8,10-teto Oxaspiro [5.5] undecane is preferred.

  One of these thermal stability and antioxidant may be used alone, or two or more thereof may be mixed and used.

  The content of the heat stabilizer and the antioxidant may be appropriately selected and determined. Usually, the total amount is 0.0001 to 0.5 with respect to 100 parts by mass of the aromatic polycarbonate resin composition (A). It is a mass part, 0.0003-0.3 mass part is preferable and 0.001-0.1 mass part is especially preferable. If the content of the heat stabilizer or the antioxidant is too small, the effect is insufficient. On the other hand, if the content is too large, the molecular weight of the polycarbonate resin may be lowered or the hue may be lowered.

(Release agent)
As the release agent, at least one selected from aliphatic carboxylic acids, aliphatic carboxylic acid esters, and polysiloxane-based silicone oils is used. Among these, at least one selected from aliphatic carboxylic acids and aliphatic carboxylic acid esters is preferably used.

  Examples of the aliphatic carboxylic acid include saturated or unsaturated aliphatic monocarboxylic acid, dicarboxylic acid, and tricarboxylic acid. Here, the aliphatic carboxylic acid also includes an alicyclic carboxylic acid. Of these, preferred aliphatic carboxylic acids are mono- or dicarboxylic acids having 6 to 36 carbon atoms, and aliphatic saturated monocarboxylic acids having 6 to 36 carbon atoms are more preferred. Specific examples of such aliphatic carboxylic acids include palmitic acid, stearic acid, valeric acid, caproic acid, capric acid, lauric acid, arachidic acid, behenic acid, lignoceric acid, serotic acid, melicic acid, tetratriacontanoic acid. , Montanic acid, glutaric acid, adipic acid, azelaic acid and the like.

  As the aliphatic carboxylic acid component constituting the aliphatic carboxylic acid ester, the same aliphatic carboxylic acid as that described above can be used. On the other hand, examples of the alcohol component constituting the aliphatic carboxylic acid ester include saturated or unsaturated monohydric alcohols and saturated or unsaturated polyhydric alcohols. These alcohols may have a substituent such as a fluorine atom or an aryl group. Among these alcohols, monovalent or polyvalent saturated alcohols having 30 or less carbon atoms are preferable, and aliphatic saturated monohydric alcohols or polyhydric alcohols having 30 or less carbon atoms are more preferable. Here, the aliphatic alcohol also includes an alicyclic alcohol.

  Specific examples of these alcohols include octanol, decanol, dodecanol, stearyl alcohol, behenyl alcohol, ethylene glycol, diethylene glycol, glycerin, pentaerythritol, 2,2-dihydroxyperfluoropropanol, neopentylene glycol, ditrimethylolpropane, dipentaerythritol. Etc.

  The aliphatic carboxylic acid ester may contain an aliphatic carboxylic acid and / or alcohol as an impurity, or may be a mixture of a plurality of compounds.

  Specific examples of the aliphatic carboxylic acid ester include beeswax (mixture based on myricyl palmitate), stearyl stearate, behenyl behenate, octyldodecyl behenate, glycerin monopalmitate, glycerin monostearate, glycerin Examples thereof include distearate, glycerin tristearate, pentaerythritol monopalmitate, pentaerythritol monostearate, pentaerythritol distearate, pentaerythritol tristearate, pentaerythritol tetrastearate and the like.

  The compounding quantity of a mold release agent is 2 mass parts or less with respect to 100 mass parts of aromatic polycarbonate resin (A), Preferably it is 1 mass part or less. When the blending amount of the release agent exceeds 2 parts by mass, there are problems such as degradation of hydrolysis resistance and mold contamination during injection molding. The release agent can be used alone or in combination.

<Manufacturing method>
The aromatic polycarbonate resin composition of the present invention is produced by mixing and melting and kneading each component constituting the aromatic polycarbonate resin composition. As the method, a method applied to a conventionally known thermoplastic resin composition can be applied. Examples thereof include a method using a ribbon blender, a Henschel mixer, a Banbury mixer, a drum tumbler, a single-screw or twin-screw extruder, a kneader, and the like. The temperature for melt kneading is not particularly limited, but is usually in the range of 240 to 320 ° C.

<Molding method>
The aromatic polycarbonate resin composition of the present invention can be used as a molding material for various molded articles. In that case, the applicable molding method can be applied as it is to the method of molding a thermoplastic resin as it is, injection molding method, extrusion molding method, hollow molding method, rotational molding method, compression molding method, differential pressure molding method And transfer molding method.

[Aromatic polycarbonate resin molding]
The molded product of the present invention is formed by molding the above-described aromatic polycarbonate resin composition of the present invention, and is excellent in light resistance, light shielding properties, light reflectivity, hue, flame retardancy, and molding stability. In addition, the impact resistance, heat resistance, dimensional stability, appearance characteristics, etc. inherent to polycarbonate resin are maintained at the same time. Taking advantage of these features, light reflectors and backlight frames for backlights of liquid crystal display devices are used. Or, it can be widely used as a light reflecting member for lighting devices such as light reflecting sheets, electric / electronic devices, advertising lamps, and automotive devices such as automotive meter panels, especially its excellent flame retardancy, Because of its light reflectivity and impact resistance, it is useful for light reflectors for liquid crystal backlights and reflector frame parts.

  EXAMPLES The present invention will be described more specifically below with reference to examples and comparative examples. However, the present invention is not limited to the following examples unless it exceeds the gist. In the following examples and comparative examples, “parts” and “%” mean “parts by mass” and “% by mass” unless otherwise specified.

[raw materials]
<Aromatic polycarbonate resin (A)>
Poly-4,4-isopropylidene diphenyl carbonate: Mitsubishi Engineering Plastics, trade name “Iupilon (registered trademark) H-3000”, viscosity average molecular weight 18,000

<Titanium oxide-based additive (B)>
Product name “Kronos 2233” manufactured by Kronos
Aluminum content a (mass%) in the titanium oxide-based additive obtained by fluorescent X-ray analysis, carbon content in the titanium oxide-based additive obtained by analysis using a high-frequency combustion carbon analyzer When c (mass%) and the average particle diameter (μm) of titanium oxide are d, d = 0.20 μm, a / d ² = 11.4, c / d ² = 12.25.

<Aromatic sulfonic acid metal salt compound (C)>
Aromatic sulfonic acid metal salt compounds (C-1) to (C-5)
Aromatic sulfonic acid metal salts having different pHs were prepared as follows.
Paratoluenesulfonic acid was dissolved in ion exchange water to prepare a 20% aqueous solution. Thereafter, an aqueous sodium hydroxide solution was added, and an aqueous sodium paratoluenesulfonate solution having different pH was prepared by adjusting the addition amount. Then, paratoluenesulfonic acid sodium salt (C-1)-(C-5) from which pH differs was obtained by heat-processing an aqueous solution and volatilizing a water | moisture content.

The prepared paratoluenesulfonic acid sodium salts (C-1) to (C-5) were each dissolved again with ion-exchanged water to prepare 10% aqueous solution, and the pH at 23 ° C. was measured using a pH meter. . In order to confirm that the neutralization reaction was completed, it was confirmed that the pH values of the 10% aqueous solution and 20% aqueous solution of paratoluenesulfonic acid sodium salt were almost the same. The pH of each paratoluenesulfonic acid sodium salt (C-1) to (C-5) was as follows.
(C-1): pH = 7.8
(C-2): pH = 6.7
(C-3): pH = 8.3
(C-4): pH = 5.6
(C-5): pH = 8.7

Aromatic sulfonic acid metal salt compound (C-6):
Paratoluenesulfonic acid sodium salt, manufactured by Chemebridge International, trade name “Chemguard NATS” (pH measured by the above method = 7.6)
Aromatic sulfonic acid metal salt compound (C-7):
Paratoluenesulfonic acid potassium salt, manufactured by Chemebridge International, trade name “Chemguard PABS” (pH measured by the above method = 7.4)
Aromatic sulfonic acid metal salt compound (C-8):
Branching sodium dodecylbenzenesulfonate (chemical _{formula: (CH 3) 2 CH-} C (CH 3) 2 -C (CH 3) 2 -C (CH 3) 2 -C 6 H 5 -SO 3 Na) ( the PH measured by the method = 6.8)

<Polyfluoroethylene (D)>
Product name "Polyflon FA-500B", manufactured by Daikin Industries

<Thermal stabilizer (E)>
Thermal stabilizer (E-1):
Tris (2,4-di-tert-butylphenyl) phosphite, manufactured by ADEKA, trade name “AS2112”
Thermal stabilizer (E-2):
Bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite, manufactured by ADEKA, trade name “PEP36”

<Release agent (F)>
Pentaerythritol distearate, manufactured by NOF Corporation, trade name “Unistar H476D”

[Examples 1-7 and Comparative Examples 1-5]
Aromatic polycarbonate resin (A), titanium oxide-based additive (B), aromatic sulfonic acid metal salt compound (C), polyfluoroethylene (D), heat so as to have the ratio (mass ratio) shown in Table 1 Stabilizer (E) and mold release agent (F) were blended and mixed with a tumbler, and then charged into a hopper of a twin screw extruder (12 blocks, TEX30XCT). Each resin component was melt-kneaded under the conditions of a cylinder temperature of 270 ° C., 200 rpm, and an extrusion rate of 25 kg / hour to obtain resin composition pellets.
The obtained resin composition was subjected to various evaluations by the following methods.
The results are shown in Table 1.

[Method for evaluating physical properties of molded products]
(1) Combustibility About each resin composition obtained in Examples and Comparative Examples, injection molding is performed under the conditions of a set temperature of 280 ° C. and a mold temperature of 80 ° C. using an injection molding machine J50 manufactured by Nippon Steel Works. A molded body having a length of 127 mm, a width of 12.7 mm, and a thickness of 1.0 mm was obtained as a test piece. About the obtained test piece, the vertical combustion test based on UL94 was done. The test results were set to V-0, V-1, and V-2 in order of goodness, and those outside the standard were classified as NG.

(2) Flow value As an evaluation of the fluidity and thermal stability of each resin composition obtained in the examples and comparative examples, the flow value (Q value) of the pellet was evaluated by the method described in Appendix C of JIS K7210. did. The measurement was performed using a flow tester CFD500D manufactured by Shimadzu Corporation, using a die having a hole diameter of 1.0 mmφ and a length of 10 mm, at test temperatures of 280 ° C., 300 ° C., and 320 ° C., with a test force of 160 kg / cm ² , a residual heat. The amount of molten resin discharged (x 0.01 cc / sec) was measured under the condition of 420 seconds.
The Q value of the aromatic polycarbonate resin (A) (Iupilon (registered trademark) H-3000) used for the preparation of the aromatic polycarbonate resin composition was 17 (× 0.01 cc / sec).

(3) Appearance About each resin composition obtained in the examples and comparative examples, using an injection molding machine J50 manufactured by Nippon Steel Works, the cylinder temperature is 280 ° C, the mold temperature is 80 ° C, and the thickness is 1 mm and 3 mm. A two-stage plate was molded and visually observed to evaluate the appearance of the molded body. Silver and resin burns were not recognized, and those with good appearance were evaluated as “◯”, and those with large appearance defects were determined as “x”.

(4) Reflectance The reflectance of the 3 mm thick part of the plate used in the appearance evaluation was measured. The measurement was performed using a spectrocolorimeter CM3600d manufactured by Konica Minolta, in a D65 / 10 degree field of view and SCI normal measurement mode, and a reflectance value at a wavelength of 440 nm was used.

From the results in Table 1, the following can be understood.
The resin compositions of Examples 1 to 7 that satisfy the conditions of the present invention have excellent flammability, thermal stability, appearance, and reflection characteristics. In Example 6, the metal of the sulfonic acid metal salt was made different, but the same effect as in Examples 1 and 2 was exhibited. Example 7 is obtained by increasing the amount of the titanium oxide-based additive in Example 1, and has more excellent reflection characteristics while having the same thermal stability as Example 1.

  On the other hand, Comparative Example 1 is inferior in reflectivity because the amount of the titanium oxide-based additive is insufficient, and Comparative Example 2 cannot obtain sufficient combustibility because the amount of the aromatic sulfonic acid metal salt is insufficient. . Comparative Example 3 cannot exhibit sufficient flammability because the pH of the aromatic sulfonic acid metal salt is low, and Comparative Example 4 is poor in thermal stability because of the high pH, and the appearance and reflectance are reduced. Since Comparative Example 5 uses dodecylbenzenesulfonic acid sodium salt having an alkyl group having 10 carbon atoms as a substituent as the aromatic sulfonic acid metal salt, the flame retardancy is inferior, and the reflectance decreases due to coloring.

  As described above, since the aromatic polycarbonate resin composition of the present invention is superior in thermal stability, flame retardancy, appearance, and light reflectance as compared with conventional aromatic polycarbonate resin compositions, liquid crystal display members It can be said that this is a suitable material for the reflecting member. Therefore, the industrial value of the present invention is remarkable.

Claims (5)

3 to 30 parts by mass of a titanium oxide-based additive (B) obtained by surface-treating titanium oxide with an alumina-based surface treatment agent and an organosiloxane-based surface treatment agent with respect to 100 parts by mass of the aromatic polycarbonate resin (A); Group 0.01-1.0 part by mass of a sulfonic acid metal salt compound (C) and polyfluoroethylene (D) 0.01-1.5 part by mass,
The aromatic ring of the aromatic sulfonic acid metal salt compound (C) does not have a substituent or has only an alkyl group having 1 to 4 carbon atoms as a substituent, and the aromatic sulfonic acid metal salt compound (C ) In an aqueous solution is 6.0 to 8.5, an aromatic polycarbonate resin composition. An aluminum content a (mass%) in the titanium oxide additive (B) obtained by fluorescent X-ray analysis of the titanium oxide additive (B) and the titanium oxide additive (B) at high frequency Carbon amount c (mass%) in the titanium oxide-based additive obtained by analysis using a combustion-type carbon analyzer, and the average particle diameter d (μm) of titanium oxide in the titanium oxide-based additive (B) Satisfies the following (formula 1) and (formula 2). The aromatic polycarbonate resin composition according to claim 1, wherein:
(Formula 1) 6.5 ≦ (a / d ² ) ≦ 15
(Equation ^{2) 5 ≦ (c / d} 2) ≦ 25   The aromatic polycarbonate resin composition according to claim 1 or 2, wherein the aromatic sulfonic acid metal salt compound (C) is toluenesulfonic acid sodium salt and / or toluenesulfonic acid potassium salt.   The molded object obtained from the aromatic polycarbonate resin composition of any one of Claim 1 thru | or 3.   The molded article according to claim 4, which is a light reflecting member.