JP6250417B2 - Thermoplastic resin composition - Google Patents

Description

  The present invention relates to a thermoplastic resin composition, and in particular, relates to an inorganic phosphor-containing thermoplastic resin composition and a molded article excellent in hue.

  Transparent thermoplastic resins such as polycarbonate resins and acrylic resins are used in a wide range of fields such as electric / electronic, mechanical, automotive, optical and medical. For example, in optical applications, it is used for lighting cover members and the like by taking advantage of its excellent transparency. There are various types of lighting covers, such as a transparent cover and a milky white translucent cover with a light diffusion function.

  In recent years, special LED lighting called a remote phosphor system has been adopted. In this remote phosphor system, a resin cover containing a phosphor is installed so as to cover the LED element at a position separated from the LED element, and a part of the light emitted from the LED element is covered by the cover. This is a system that converts the wavelength and finally emits white light or the like (for example, Patent Document 1).

Examples of the inorganic phosphor used for the cover material for remote phosphor include phosphors of various oxides, nitrides, oxynitrides, sulfides, and oxysulfides, such as Y A YAG yellow phosphor having a garnet structure represented by ₃ Al ₅ O ₁₂ : Ce is used.
However, it has been found that when these inorganic phosphors are blended with a transparent thermoplastic resin, the color tends to be changed to a dark color by melt kneading or molding, and partial appearance defects such as black stripes are likely to occur. Such discoloration has been found to be a serious problem because it causes deterioration of light transmission, which is the most important characteristic in lighting cover applications.

JP2012-064345A

  In view of the above situation, the object of the present invention is to use a resin composition comprising an inorganic phosphor in a transparent thermoplastic resin, and to obtain a hue and light transmission of a molded product obtained by melt-kneading, molding, or the like. It is providing the thermoplastic resin composition which can improve property.

As a result of intensive studies to solve the above problems, the present inventor has found that the above defects are caused by friction and high shear in the kneading screw or cylinder when the inorganic phosphor is melt-kneaded with the transparent thermoplastic resin. As a result of inferring that it is due to discoloration caused by force, and further investigations, the hue and light transmittance can be improved by adding a specific amount of fatty acid amide to the transparent thermoplastic resin and inorganic phosphor. As a result, the present invention has been found.
The present invention provides the following thermoplastic resin composition and molded article.

[1] (A) 0.1 to 20 parts by mass of an inorganic phosphor and (C) 0.001 to 3 parts by mass of a fatty acid amide with respect to 100 parts by mass of a transparent thermoplastic resin Thermoplastic resin composition.
[2] The thermoplastic resin composition according to [1], wherein the (A) transparent thermoplastic resin is a polycarbonate resin.
[3] The thermoplastic resin composition according to the above [1] or [2], further comprising (D) a light diffusing agent in an amount of 0.01 to 10 parts by mass with respect to 100 parts by mass of the (A) transparent thermoplastic resin. object.
[4] The thermoplastic resin composition according to any one of [1] to [3], wherein (C) a fatty acid amide is externally added.
[5] A molded product obtained by injection molding the thermoplastic resin composition according to any one of [1] to [4].
[6] The molded article according to [5], which is a lighting cover.
[7] The molded article according to the above [5] or [6], which is a light-transmitting cover for a remote phosphor type LED light-emitting device.

  According to the thermoplastic resin composition of the present invention, it is possible to provide a molded article having high light transmittance and having no problem of discoloration or appearance defect while containing an inorganic phosphor in a transparent thermoplastic resin. In particular, a suitable resin material can be provided as an illumination cover for an LED illumination device, a light-transmitting cover (such as a globe) for a remote phosphor type LED light-emitting device, or the like.

Hereinafter, although an embodiment, an example thing, etc. are shown and explained in detail about the present invention, the present invention is limited to an embodiment, an example, etc. shown below and is not interpreted.
In the present specification, unless otherwise specified, “to” is used in a sense that includes numerical values described before and after it as a lower limit value and an upper limit value. Further, “part” means a part by mass based on the mass standard unless otherwise specified.

[Overview]
The thermoplastic resin composition of the present invention comprises (B) 0.1 to 20 parts by mass of inorganic phosphor and (C) 0.001 to 3 parts by mass of fatty acid amide with respect to 100 parts by mass of (A) transparent thermoplastic resin. It is characterized by containing.

[(A) Transparent thermoplastic resin]
The transparent thermoplastic resin (A) which is the main component of the thermoplastic resin composition of the present invention includes polycarbonate resins; acrylic resins such as polymethyl methacrylate and polymethacrylate; alicyclic polyolefin resins including norbornene and the like. Cyclic polyolefin resins; copolymers of ethylene and methyl-, ethyl-, propyl-, butyl-acrylates or methacrylates, ethylene-acrylic acid copolymers and other ionomer resins; polystyrene resins, ABS resins, AS resins, Styrenic resins such as AAS resin, AES resin, and MBS resin; Polyester resins such as polyethylene terephthalate resin and polybutylene terephthalate resin; Modified polyphenylene ether resin; Polyarylate resin; Polyetherimide resin; , And these one or more blend thereof.
Of these, polycarbonate resins, acrylic resins, and alicyclic polyolefin resins are preferable, and polycarbonate resins are more preferable.

[(A1) Polycarbonate resin]
There is no restriction | limiting in the kind of (A1) polycarbonate resin used for the thermoplastic resin composition of this invention. Moreover, (A1) polycarbonate resin may use 1 type and may use 2 or more types together by arbitrary combinations and arbitrary ratios.
The polycarbonate resin is a polymer having a basic structure having a carbonic acid bond represented by a general formula: — (— O—X—O—C (═O) —) —. In the formula, X is generally a hydrocarbon group, but for imparting various properties, X introduced with a hetero atom or a hetero bond may be used.
The polycarbonate resin can be classified into an aromatic polycarbonate resin in which the carbon directly bonded to the carbonic acid bond is an aromatic carbon, and an aliphatic polycarbonate resin in which the carbon is an aliphatic carbon. From the viewpoint of electrical characteristics and the like, it is preferable to use an aromatic polycarbonate resin.

(A1) Although there is no restriction | limiting in the specific kind of polycarbonate resin, For example, the polycarbonate resin formed by making a dihydroxy compound and a carbonate precursor react is mentioned. At this time, in addition to the dihydroxy compound and the carbonate precursor, a polyhydroxy compound or the like may be reacted. Alternatively, a method of reacting carbon dioxide with a cyclic ether using a carbonate precursor may be used.
Moreover, (A1) polycarbonate resin may be linear or branched. Furthermore, the (A1) polycarbonate resin may be a homopolymer composed of one type of repeating unit or a copolymer having two or more types of repeating units. At this time, the copolymer can be selected from various copolymerization forms such as a random copolymer and a block copolymer. In general, such a polycarbonate polymer is a thermoplastic resin.

(A1) Among the monomers used as the raw material for the polycarbonate resin, examples of the aromatic dihydroxy compound include:
Dihydroxybenzenes such as 1,2-dihydroxybenzene, 1,3-dihydroxybenzene (ie, resorcinol), 1,4-dihydroxybenzene;
Dihydroxybiphenyls such as 2,5-dihydroxybiphenyl, 2,2′-dihydroxybiphenyl, 4,4′-dihydroxybiphenyl;
2,2′-dihydroxy-1,1′-binaphthyl, 1,2-dihydroxynaphthalene, 1,3-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, , 7-dihydroxynaphthalene, dihydroxynaphthalene such as 2,7-dihydroxynaphthalene;

2,2′-dihydroxydiphenyl ether, 3,3′-dihydroxydiphenyl ether, 4,4′-dihydroxydiphenyl ether, 4,4′-dihydroxy-3,3′-dimethyldiphenyl ether, 1,4-bis (3-hydroxyphenoxy) Dihydroxy diaryl ethers such as benzene and 1,3-bis (4-hydroxyphenoxy) benzene;

2,2-bis (4-hydroxyphenyl) propane (ie, bisphenol A),
1,1-bis (4-hydroxyphenyl) propane,
2,2-bis (3-methyl-4-hydroxyphenyl) propane,
2,2-bis (3-methoxy-4-hydroxyphenyl) propane,
2- (4-hydroxyphenyl) -2- (3-methoxy-4-hydroxyphenyl) propane,
1,1-bis (3-tert-butyl-4-hydroxyphenyl) propane,
2,2-bis (3,5-dimethyl-4-hydroxyphenyl) propane,
2,2-bis (3-cyclohexyl-4-hydroxyphenyl) propane,
2- (4-hydroxyphenyl) -2- (3-cyclohexyl-4-hydroxyphenyl) propane,
α, α′-bis (4-hydroxyphenyl) -1,4-diisopropylbenzene,
1,3-bis [2- (4-hydroxyphenyl) -2-propyl] benzene,
Bis (4-hydroxyphenyl) methane,
Bis (4-hydroxyphenyl) cyclohexylmethane,
Bis (4-hydroxyphenyl) phenylmethane,
Bis (4-hydroxyphenyl) (4-propenylphenyl) methane,
Bis (4-hydroxyphenyl) diphenylmethane,
Bis (4-hydroxyphenyl) naphthylmethane,
1,1-bis (4-hydroxyphenyl) ethane,
1,1-bis (4-hydroxyphenyl) -1-phenylethane,
1,1-bis (4-hydroxyphenyl) -1-naphthylethane,
1,1-bis (4-hydroxyphenyl) butane,
2,2-bis (4-hydroxyphenyl) butane,
2,2-bis (4-hydroxyphenyl) pentane,
1,1-bis (4-hydroxyphenyl) hexane,
2,2-bis (4-hydroxyphenyl) hexane,
1,1-bis (4-hydroxyphenyl) octane,
2,2-bis (4-hydroxyphenyl) octane,
1,1-bis (4-hydroxyphenyl) hexane,
2,2-bis (4-hydroxyphenyl) hexane,
4,4-bis (4-hydroxyphenyl) heptane,
2,2-bis (4-hydroxyphenyl) nonane,
1,1-bis (4-hydroxyphenyl) decane,
1,1-bis (4-hydroxyphenyl) dodecane,
Bis (hydroxyaryl) alkanes such as;

1,1-bis (4-hydroxyphenyl) cyclopentane,
1,1-bis (4-hydroxyphenyl) cyclohexane,
1,1-bis (4-hydroxyphenyl) -3,3-dimethylcyclohexane,
1,1-bis (4-hydroxyphenyl) -3,4-dimethylcyclohexane,
1,1-bis (4-hydroxyphenyl) -3,5-dimethylcyclohexane,
1,1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane,
1,1-bis (4-hydroxy-3,5-dimethylphenyl) -3,3,5-trimethylcyclohexane,
1,1-bis (4-hydroxyphenyl) -3-propyl-5-methylcyclohexane,
1,1-bis (4-hydroxyphenyl) -3-tert-butyl-cyclohexane,
1,1-bis (4-hydroxyphenyl) -4-tert-butyl-cyclohexane,
1,1-bis (4-hydroxyphenyl) -3-phenylcyclohexane,
1,1-bis (4-hydroxyphenyl) -4-phenylcyclohexane,
Bis (hydroxyaryl) cycloalkanes such as;

Cardostructure-containing bisphenols such as 9,9-bis (4-hydroxyphenyl) fluorene, 9,9-bis (4-hydroxy-3-methylphenyl) fluorene;

Dihydroxy diaryl sulfides such as 4,4'-dihydroxydiphenyl sulfide, 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfide;

Dihydroxydiaryl sulfoxides such as 4,4'-dihydroxydiphenyl sulfoxide, 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfoxide;

Dihydroxydiaryl sulfones such as 4,4'-dihydroxydiphenyl sulfone and 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfone;

Among these, bis (hydroxyaryl) alkanes are preferable, and bis (4-hydroxyphenyl) alkanes are preferable, and 2,2-bis (4-hydroxyphenyl) propane (ie, from the viewpoint of impact resistance and heat resistance). Bisphenol A) is preferred.
In addition, 1 type may be used for an aromatic dihydroxy compound and it may use 2 or more types together by arbitrary combinations and a ratio.

  (A1) Among the monomers used as the raw material for the polycarbonate resin, carbonyl halides, carbonate esters, and the like are used as examples of carbonate precursors. In addition, 1 type may be used for a carbonate precursor and it may use 2 or more types together by arbitrary combinations and a ratio.

  Specific examples of carbonyl halides include phosgene; haloformates such as bischloroformate of dihydroxy compounds and monochloroformate of dihydroxy compounds.

  Specific examples of the carbonate ester include diaryl carbonates such as diphenyl carbonate and ditolyl carbonate; dialkyl carbonates such as dimethyl carbonate and diethyl carbonate; biscarbonate bodies of dihydroxy compounds, monocarbonate bodies of dihydroxy compounds, and cyclic carbonates. And carbonate bodies of dihydroxy compounds such as

  (A1) The manufacturing method of polycarbonate resin is not specifically limited, A well-known arbitrary method is employable. Examples thereof include an interfacial polymerization method, a melt transesterification method, a pyridine method, a ring-opening polymerization method of a cyclic carbonate compound, and a solid phase transesterification method of a prepolymer.

  (A1) The molecular weight of the polycarbonate resin may be appropriately selected and determined, but is usually 12,000 or more, preferably 15,000 or more, more preferably 17, in terms of viscosity average molecular weight [Mv] converted from the solution viscosity. 000 or more, particularly 20,000 or more, and usually 36,000 or less, preferably 34,000 or less, more preferably 32,000 or less, still more preferably 30,000 or less, particularly preferably 29,000 or less. It is. By setting the viscosity average molecular weight to be equal to or higher than the lower limit of the above range, the mechanical strength of the thermoplastic resin composition can be further improved, which is more preferable when used for applications requiring high mechanical strength. On the other hand, by making the viscosity average molecular weight not more than the upper limit of the above range, it is possible to suppress and improve the fluidity drop of the thermoplastic resin composition of the present invention, so that the molding processability can be improved and the molding process can be easily performed. Become.

In the present invention, the viscosity average molecular weight [Mv] refers to the intrinsic viscosity [η] (unit dl / g) at a temperature of 20 ° C. using a Ubbelohde viscometer using methylene chloride as a solvent. It means a value calculated from the viscosity formula, that is, η = 1.23 × 10 ⁻⁴ Mv ^0.83 . The intrinsic viscosity [η] is a value calculated from the following equation by measuring the specific viscosity [η _sp ] at each solution concentration [C] (g / dl).

  (A1) The polycarbonate resin is a polycarbonate resin alone (a polycarbonate resin alone is not limited to an embodiment containing only one type of polycarbonate resin, and includes, for example, an embodiment containing a plurality of types of polycarbonate resins having different monomer compositions and molecular weights. It may be used in the sense) or may be used in combination with an alloy (mixture) of a polycarbonate resin and another thermoplastic resin. Further, for example, for the purpose of further improving flame retardancy and impact resistance, a polycarbonate resin is copolymerized with an oligomer or polymer having a siloxane structure; for the purpose of further improving thermal oxidation stability and flame retardancy A monomer, oligomer or polymer having a copolymer; a monomer, oligomer or polymer having a dihydroxyanthraquinone structure for the purpose of improving thermal oxidation stability; A copolymer with an oligomer or polymer having an olefin structure; a copolymer with a polyester resin oligomer or polymer for the purpose of improving chemical resistance; Good.

  Further, in order to improve the appearance of the molded product and the fluidity, (A1) the polycarbonate resin may contain a polycarbonate oligomer. The viscosity average molecular weight [Mv] of this polycarbonate oligomer is usually 1,500 or more, preferably 2,000 or more, and usually 9,500 or less, preferably 9,000 or less. Furthermore, the polycarbonate ligomer contained is preferably 30% by mass or less of the polycarbonate resin (including the polycarbonate oligomer).

[(A2) Acrylic resin]
As the (A2) acrylic resin, a (co) polymer containing a methyl methacrylate unit as a main component and containing 0 to 5% by mass of other acrylic ester units is preferable. The acrylic resin preferably has a mass average molecular weight in the range of 30,000 to 250,000. If a material having a mass average molecular weight lower than 30,000 is used, the resulting resin composition tends to have a low mechanical strength. Moreover, in the thing higher than 250,000, the fluidity | liquidity of a resin composition worsens and a moldability tends to deteriorate. In addition, a mass average molecular weight says the value of polystyrene conversion by a gel permeation chromatography (GPC) method.

  The acrylic ester units that can be copolymerized with methyl methacrylate units are specifically methyl acrylate, ethyl acrylate, acrylic acid-n-butyl, acrylic acid-iso-butyl, acrylic acid-t-butyl. , Acrylic acid alkyl esters such as 2-ethylhexyl acrylate, cyclohexyl acrylate, methyl cyclohexyl acrylate, bornyl acrylate, isobornyl acrylate, adamantyl acrylate, cycloalkyl acrylates, phenyl acrylate, acrylic acid Acrylic acid aromatic esters such as benzyl, acrylic acid-substituted aromatic esters such as fluorophenyl acrylate, chlorophenyl acrylate, fluorobenzyl acrylate, chlorobenzyl acrylate, and fluoromethacrylate Acrylic acid alkyl halide esters such as acrylic acid fluoroethyl, hydroxy alkyl acrylate, glycidyl acrylate, ethylene glycol ester and acrylic acid polyethylene glycol esters. These acrylic acid ester units can use 1 type (s) or 2 or more types. Of these, methyl acrylate is preferred.

[(A3) Alicyclic polyolefin resin]
(A3) The alicyclic polyolefin resin is a polyolefin resin containing an alicyclic structure in the main chain, and the alicyclic structure includes a saturated alicyclic hydrocarbon (cycloalkane) structure, an unsaturated alicyclic hydrocarbon. (Cycloalkene) structure and the like can be mentioned. From the viewpoints of mechanical strength and heat resistance, a cycloalkane structure and a cycloalkene structure are preferable, and a cycloalkane structure is most preferable. Although there is no special restriction | limiting in the number of carbon atoms which comprises an alicyclic structure, Usually, 4-30 pieces, Preferably it is 5-20 pieces, More preferably, it is the range of 5-15 pieces.
The proportion of the repeating unit containing the alicyclic structure in the alicyclic polyolefin resin may be appropriately selected according to the purpose of use, but is preferably 55% by mass or more, more preferably 70% by mass or more, particularly Preferably it is 90 mass% or more. When the ratio of the repeating unit having an alicyclic structure in the alicyclic polyolefin resin is within this range, the transparency and heat resistance of the thermoplastic resin composition of the present invention are improved.

  Examples of (A3) alicyclic polyolefin resins include norbornene resins, monocyclic olefin resins, cyclic conjugated diene resins, vinyl alicyclic hydrocarbon resins, and hydrides thereof. . Among these, norbornene-based resins can be suitably used because of their good transparency and moldability.

  Examples of the norbornene-based resin include a ring-opening polymer of a monomer having a norbornene structure, a ring-opening polymer of a monomer having a norbornene structure and another monomer, a hydride thereof, or a norbornene structure. Examples thereof include addition polymers of monomers, addition polymers of monomers having a norbornene structure and other monomers, and hydrides thereof.

Examples of monomers having a norbornene structure include bicyclo [2.2.1] hept-2-ene (common name: norbornene), tricyclo [4.3.0.1 ^2,5 ] deca-3,7-diene. (Common name: dicyclopentadiene), 7,8-benzotricyclo [4.3.0.1 ^2,5 ] dec-3-ene (common name: methanotetrahydrofluorene), tetracyclo [4.4.0. 1 ^2,5 . 1 ^7,10 ] dodec-3-ene (common name: tetracyclododecene), and derivatives of these compounds (for example, those having a substituent in the ring).

Other monomers capable of ring-opening copolymerization with monomers having a norbornene structure include monocyclic olefins such as cyclohexene, cycloheptene, and cyclooctene and derivatives thereof; cyclic conjugated dienes such as cyclohexadiene and cycloheptadiene; Derivatives thereof; and the like.
A ring-opening polymer of a monomer having a norbornene structure and a ring-opening copolymer of a monomer having a norbornene structure and another monomer copolymerizable with the monomer have a known ring-opening polymerization catalyst. It can be obtained by (co) polymerization in the presence.

Examples of other monomers that can be addition copolymerized with a monomer having a norbornene structure include α-olefins having 2 to 20 carbon atoms such as ethylene, propylene, and 1-butene, and derivatives thereof; cyclobutene, cyclopentene, And cycloolefins such as cyclohexene and derivatives thereof; non-conjugated dienes such as 1,4-hexadiene, 4-methyl-1,4-hexadiene, 5-methyl-1,4-hexadiene, and the like. These monomers can be used alone or in combination of two or more. Among these, α-olefin is preferable and ethylene is more preferable.
An addition polymer of a monomer having a norbornene structure and an addition copolymer of a monomer having a norbornene structure with another monomer copolymerizable with a monomer having a norbornene structure are prepared in the presence of a known addition polymerization catalyst. It can be obtained by polymerization.

  A hydrogenated product of a ring-opening polymer of a monomer having a norbornene structure, a hydrogenated product of a ring-opening copolymer of a monomer having a norbornene structure and another monomer capable of ring-opening copolymerization thereof, Hydrogenated products of addition polymers of monomers having a norbornene structure and hydrogenated products of addition polymers of monomers having a norbornene structure and other monomers copolymerizable therewith are not A known hydrogenation catalyst containing a transition metal such as nickel or palladium is added to the combined solution, and the carbon-carbon unsaturated bond is preferably hydrogenated by 90% or more.

  (A3) The molecular weight of the alicyclic polyolefin resin is appropriately selected according to the purpose of use, but is usually a polyisoprene-converted mass average molecular weight (Mw) measured by gel permeation chromatography using cyclohexane as a solvent. It is 10,000 to 100,000, preferably 15,000 to 80,000, more preferably 20,000 to 50,000.

[(B) Inorganic phosphor]
As the (B) inorganic phosphor contained in the thermoplastic resin composition of the present invention, various inorganic phosphors can be used, and various phosphors such as red (orange), green, blue, and yellow can be mentioned.
Examples of red phosphors include CaAlSiN ₃ : Eu (abbreviated as “CASN”), (Sr, Ca) AlSiN ₃ : Eu (abbreviated as “SCASN”), and Ca _1-x Al _{1 1−. x Si 1 + x N 3-} x O x: Eu, CaAlSiN 3: Eu, (Sr, Ba, Ca) 3 SiO 5: Eu , and the like preferably.
Examples of the green phosphor include (Ba, Ca, Sr, Mg) ₂ SiO ₄ : Eu, Si _6-z Al _z N _{8 -z} O _z : Eu, and M ₃ Si ₆ O ₁₂ N ₂ : Eu (M Is preferably an alkaline earth metal element).
As the blue phosphor, (Sr, Ca, Ba) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu ²⁺ and BaMgAl ₁₀ O ₁₇ : Eu can be preferably used.
As the yellow phosphor, a garnet phosphor is preferably used, and in particular, Y ₃ Al ₅ O ₁₂ : Ce (also referred to as “YAG”) is preferably used.
These phosphors can be used alone or in combination of two or more at an arbitrary ratio.

  (B) Although there is no limitation in the magnitude | size of an inorganic fluorescent substance, a magnitude | size is in the range of 0.1-100 micrometers normally with an average particle diameter, Preferably it is 1-50 micrometers. If the average particle size is less than 0.1 μm, the wavelength conversion efficiency tends to be insufficient. On the other hand, if it exceeds 100 μm, it is difficult to obtain the hue improving effect of the present invention, and the mechanical strength of the resulting thermoplastic resin composition may be lowered, which is not preferable. (B) The shape of the inorganic phosphor is not particularly limited, but is usually indefinite.

The Mohs hardness of (B) the inorganic phosphor is usually 6 or more, preferably 7 or more, more preferably 8 or more. Since inorganic phosphors with higher Mohs hardness are more likely to cause discoloration problems, it is considered that the effect of improving hue by blending (C) fatty acid amide is great.
Note that the Mohs hardness is an index obtained by quantifying the hardness of a substance, but in the present invention, an index classified into 10 levels is used.

These inorganic phosphors may be those treated with various surface treatment agents such as a silane coupling agent, a titanate coupling agent, methyl hydrogen polysiloxane, silicone oil, and a fatty acid-containing hydrocarbon compound. Among these, in particular, methyltrimethoxysilane, ethyltrimethoxysilane, octyltrimethoxysilane, alkyltrimethoxysilane such as dodecyltrimethoxysilane, methyl having a kinematic viscosity in the range of 5 to 10,000 mm ² / s at 25 ° C. hydrogen polysiloxane, dimethyl silicone oil or methylphenyl silicone oil 5-10000 ^mm 2 / s at a kinematic viscosity of 25 ° C. are preferred, kinematic viscosity at 25 ° C. of 10~1,000mm ² / s methylhydrogenpolysiloxane Polysiloxane is more preferred.
The amount of the surface treatment agent is preferably in the range of 0.001 to 10 parts by mass, more preferably in the range of 0.1 to 3 parts by mass with respect to 100 parts by mass of the inorganic phosphor. A known method can be arbitrarily used for the surface treatment.

  (B) Content of inorganic fluorescent substance is 0.1-20 mass parts with respect to 100 mass parts of (A) transparent thermoplastic resin, Preferably it is 0.5 mass part or more, More preferably, it is 1 mass part or more. And preferably 15 parts by mass or less, more preferably 10 parts by mass or less. If the content is less than 0.1 parts by mass, the wavelength conversion efficiency of light is insufficient, and if it is more than 20 parts by mass, the mechanical strength of the resulting thermoplastic resin composition is greatly reduced, which is not preferable.

[(C) Fatty acid amide]
The fatty acid amide (C) contained in the thermoplastic resin composition of the present invention is a fatty acid amide or a fatty acid bisamide, and a compound obtained by a dehydration reaction between a fatty acid and / or a polybasic acid and a diamine is preferred.
The fatty acid is preferably a saturated aliphatic monocarboxylic acid having 16 or more carbon atoms, more preferably 16 to 30 carbon atoms. Specific examples include palmitic acid, stearic acid, behenic acid, and montanic acid.
The polybasic acid is a carboxylic acid of dibasic acid or more, for example, aliphatic dicarboxylic acids such as malonic acid, succinic acid, adipic acid, sebacic acid, pimelic acid, azelaic acid, and aromatics such as phthalic acid and terephthalic acid. Examples thereof include dicarboxylic acids and alicyclic dicarboxylic acids such as cyclohexyl dicarboxylic acid and cyclohexyl succinic acid.
Examples of the amine include methylamine, ethylamine, propylamine, butylamine, hexylamine, octylamine, decylamine, stearylamine, dimethylamine, diethylamine, dipropylamine, dibutylamine and the like.
Examples of the diamine include ethylenediamine, 1,3-diaminopropane, 1,4-diaminobutane, hexamethylenediamine, metaxylylenediamine, tolylenediamine, paraxylylenediamine, phenylenediamine, and isophoronediamine. Among these, a linear saturated aliphatic diamine having 2 to 20 carbon atoms is preferable.

Specific examples of (C) fatty acid amides include stearic acid amide, behenic acid amide, and montanic acid amide, and fatty acid bisamides include the above fatty acids and 1 to 10 carbon atoms, preferably Include fatty acid bisamides obtained by reaction with aliphatic diamines having 1 to 6 carbon atoms, specifically methylene bis stearic acid amide, ethylene bis stearic acid amide, ethylene bis behenic acid amide, ethylene bis palmitic acid. And acid amide, ethylene bis (12-hydroxystearic acid amide), hexamethylene bis (12-hydroxystearic acid amide) and the like. Of these, stearamide and ethylene bis stearamide are preferable.
These fatty acid amides may be used alone or in combination of two or more.

  (C) When fatty acid amide has melting | fusing point, it is preferable that melting | fusing point by a differential scanning calorimeter (DSC) is 40-260 degreeC, 100-230 degreeC is more preferable, It is 120-200 degreeC More preferably. When the melting point is less than 40 ° C., the handling during the production of the thermoplastic resin composition tends to be difficult, and when it exceeds 260 ° C., the friction reducing effect tends to be small, and the hue improving effect of the present invention is reduced. There is a case.

  In this specification, the melting point refers to the melting point by differential scanning calorimetry (DSC), and refers to the peak temperature (° C.) of the main peak of melting. Specifically, it refers to the peak top temperature (° C.) of the exothermic main peak detected when the temperature is raised from 30 ° C. to the expected melting point + 40 ° C. at 20 ° C./min in a nitrogen atmosphere.

  (C) Content of fatty acid amide is 0.001-3 mass parts with respect to 100 mass parts of (A) transparent thermoplastic resin, Preferably it is 0.005 mass part or more, More preferably, 0.01 mass part It is above, Preferably it is 1 mass part or less, More preferably, it is 0.5 mass part or less, More preferably, it is 0.3 mass part or less. When the content is less than 0.001 part by mass, the effect of improving the hue is small, and when the content is more than 3 parts by mass, an increase in heat generation gas or mold contamination due to mold deposits is caused, which is not preferable.

[(D) Light diffusing agent]
The thermoplastic resin composition of the present invention preferably further contains (D) a light diffusing agent. (D) By containing a light diffusing agent, not only can the light diffusibility and glare reduction function be used in applications such as illumination covers, but also (B) the wavelength conversion efficiency of the inorganic phosphor is increased. It is preferable because the content of the inorganic phosphor can be reduced.
(D) The light diffusing agent is fine inorganic or organic particles, and examples thereof include organic fine particles such as calcium carbonate fine particles, glass fine particles, polystyrene resins, (meth) acrylic resins, and silicone resins. Transparent organic fine particles are preferred. Further, the fine particles are preferably spherical in terms of light transmittance and light diffusion effect.
The preferable average particle diameter of the particulate light diffusing agent is 0.1 to 50 μm, more preferably 0.5 to 30 μm, and particularly 1 to 10 μm.

As such organic fine particles, crosslinked organic fine particles that do not melt in the resin even when heated to the molding temperature of the transparent thermoplastic resin are preferable. Specifically, crosslinked (meth) acrylic resins, silicone-based resins are used. Organic fine particles. Specific examples include partially cross-linked polymethyl methacrylate polymer fine particles, cross-linked silicone resin particles, silicone rubber powder obtained by coating a silicone rubber with a silicone resin, and the like.
Among these, silicone resin organic fine particles are preferable, polyorganosilsesquioxane particles are more preferable, and polymethylsilsesquioxane particles are particularly preferable from the viewpoint of excellent thermal stability.

  (D) The preferable content of the light diffusing agent is 0.01 to 10 parts by mass, and more preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of the (A) transparent thermoplastic resin. When the content ratio of the light diffusing agent is less than 0.01 parts by mass, the light diffusibility is insufficient, the high-brightness LED light source is easily seen through, the dazzling reduction effect is insufficient, and (B) the inorganic phosphor The blending effect of the light diffusing agent is difficult to obtain, such as when it is necessary to blend a large amount. On the other hand, when there is too much content of a light-diffusion agent, transparency and a fluid fall may be caused, and it is unpreferable.

[Other additives]
Moreover, in the range which does not impair the effect of this invention, (A) thermoplastic resins other than a transparent thermoplastic resin, and also various additives may be contained. Examples of such additives include heat stabilizers, antioxidants, (C) mold release agents other than fatty acid amides, flame retardants, ultraviolet absorbers, dyes and pigments, fluorescent whitening agents, antistatic agents, antifogging agents, Examples thereof include a lubricant, an antiblocking agent, a fluidity improver, a plasticizer, a dispersant, an antibacterial agent, a reinforcing filler, and an elastomer.

-Heat stabilizer As a heat stabilizer, a phosphorus compound is mentioned, for example. Any known phosphorous compound can be used. Specific examples include phosphorus oxo acids such as phosphoric acid, phosphonic acid, phosphorous acid, phosphinic acid, and polyphosphoric acid; acidic pyrophosphate metal salts such as acidic sodium pyrophosphate, acidic potassium pyrophosphate, and acidic calcium pyrophosphate; phosphoric acid Examples thereof include phosphates of Group 1 or Group 10 metals such as potassium, sodium phosphate, cesium phosphate, and zinc phosphate; organic phosphate compounds, organic phosphite compounds, and organic phosphonite compounds.

  Among them, triphenyl phosphite, tris (monononylphenyl) phosphite, tris (monononyl / dinonyl phenyl) phosphite, tris (2,4-di-tert-butylphenyl) phosphite, monooctyl diphenyl phosphite, Dioctyl monophenyl phosphite, monodecyl diphenyl phosphite, didecyl monophenyl phosphite, tridecyl phosphite, trilauryl phosphite, tristearyl phosphite, 2,2-methylenebis (4,6-di-tert-butylphenyl) ) Organic phosphites such as octyl phosphite are preferred.

  The blending amount of the heat stabilizer is usually 0.001 parts by mass or more, preferably 0.005 parts by mass or more, more preferably 0.01 parts by mass or more with respect to 100 parts by mass of the (A) transparent thermoplastic resin. Moreover, it is 1 mass part or less normally, Preferably it is 0.5 mass part or less, More preferably, it is 0.3 mass part or less. If there is too little heat stabilizer, the blending effect of the heat stabilizer will be insufficient, and the hue may deteriorate due to retention at high temperature. If there is too much heat stabilizer, the heat stability will decrease and the hue will decrease. It may get worse.

-Antioxidant As an antioxidant, a hindered phenolic antioxidant is mentioned, for example. Specific examples thereof include pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl). ) Propionate, thiodiethylenebis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], N, N′-hexane-1,6-diylbis [3- (3,5-di-) tert-butyl-4-hydroxyphenylpropionamide), 2,4-dimethyl-6- (1-methylpentadecyl) phenol, diethyl [[3,5-bis (1,1-dimethylethyl) -4-hydroxyphenyl ] Methyl] phosphoate, 3,3 ′, 3 ″, 5,5 ′, 5 ″ -hexa-tert-butyl-a, a ′, a ″-(me Citylene-2,4,6-triyl) tri-p-cresol, 4,6-bis (octylthiomethyl) -o-cresol, ethylenebis (oxyethylene) bis [3- (5-tert-butyl-4- Hydroxy-m-tolyl) propionate], hexamethylenebis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], 1,3,5-tris (3,5-di-tert- Butyl-4-hydroxybenzyl) -1,3,5-triazine-2,4,6 (1H, 3H, 5H) -trione, 2,6-di-tert-butyl-4- (4,6-bis ( Octylthio) -1,3,5-triazin-2-ylamino) phenol and the like.

  Among them, pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate preferable.

  The content of the antioxidant is usually 0.001 parts by mass or more, preferably 0.01 parts by mass or more, and usually 1 part by mass or less, preferably 100 parts by mass of the transparent thermoplastic resin (A). Is 0.5 parts by mass or less. When the content of the antioxidant is less than the lower limit of the above range, the effect as an antioxidant may be insufficient, the hue may deteriorate due to retention at high temperatures, and the improvement of heat aging properties may be insufficient. If the content of the antioxidant exceeds the upper limit of the above range, the effect reaches its peak and may not be economical.

-Release agent (C) Examples of release agents other than fatty acid amides include aliphatic carboxylic acids, esters of aliphatic carboxylic acids and alcohols, aliphatic hydrocarbon compounds having a number average molecular weight of 200 to 15,000, poly Examples thereof include siloxane-based silicone oil.

  Examples of the aliphatic carboxylic acid include saturated or unsaturated aliphatic monovalent, divalent or trivalent carboxylic acid. Here, the aliphatic carboxylic acid includes alicyclic carboxylic acid. Among these, preferable aliphatic carboxylic acids are monovalent or divalent carboxylic acids having 6 to 36 carbon atoms, and aliphatic saturated monovalent carboxylic acids having 6 to 36 carbon atoms are more preferable. Specific examples of such aliphatic carboxylic acids include palmitic acid, stearic acid, caproic acid, capric acid, lauric acid, arachidic acid, behenic acid, lignoceric acid, serotic acid, mellicic acid, tetrariacontanoic acid, montanic acid, adipine Examples include acids and azelaic acid.

  As aliphatic carboxylic acid in ester of aliphatic carboxylic acid and alcohol, the same thing as the said aliphatic carboxylic acid can be used, for example. On the other hand, examples of the alcohol include saturated or unsaturated monohydric or polyhydric alcohols. These alcohols may have a substituent such as a fluorine atom or an aryl group. Among these, a monovalent or polyvalent saturated alcohol having 30 or less carbon atoms is preferable, and an aliphatic or alicyclic saturated monohydric alcohol or aliphatic saturated polyhydric alcohol having 30 or less carbon atoms is more preferable.

  Specific examples of such alcohols include octanol, decanol, dodecanol, stearyl alcohol, behenyl alcohol, ethylene glycol, diethylene glycol, glycerin, pentaerythritol, 2,2-dihydroxyperfluoropropanol, neopentylene glycol, ditrimethylolpropane, dipentaerythritol, and the like. Is mentioned.

  Specific examples of esters of aliphatic carboxylic acids and alcohols include beeswax (a mixture based on myricyl palmitate), stearyl stearate, behenyl behenate, stearyl behenate, glycerin monopalmitate, glycerin monostearate Examples thereof include rate, glycerol distearate, glycerol tristearate, pentaerythritol monopalmitate, pentaerythritol monostearate, pentaerythritol distearate, pentaerythritol tristearate, pentaerythritol tetrastearate and the like. The ester of the aliphatic carboxylic acid and the alcohol is preferably a full ester.

Examples of the aliphatic hydrocarbon having a number average molecular weight of 200 to 15,000 include liquid paraffin, paraffin wax, microwax, polyethylene wax, Fischer-Tropsch wax, and α-olefin oligomer having 3 to 12 carbon atoms. Here, the aliphatic hydrocarbon includes alicyclic hydrocarbons.
Among these, paraffin wax, polyethylene wax, or a partial oxide of polyethylene wax is preferable, and paraffin wax and polyethylene wax are more preferable.
The number average molecular weight of the aliphatic hydrocarbon is preferably 5,000 or less.

  The content of the release agent is preferably 0.001 to 3 parts by mass, more preferably 0.01 parts by mass or more, and more preferably with respect to 100 parts by mass of (A) the transparent thermoplastic resin. Is 2 parts by mass or less, more preferably 1 part by mass or less. If the content of the release agent is less than the lower limit of the above range, the effect of releasability may not be sufficient, and if the content of the release agent exceeds the upper limit of the above range, Mold contamination may occur.

UV absorbers Examples of UV absorbers include inorganic UV absorbers such as cerium oxide and zinc oxide; benzotriazole compounds, benzophenone compounds, salicylate compounds, cyanoacrylate compounds, triazine compounds, oxanilide compounds, malonic ester compounds, hindered amines Examples include organic ultraviolet absorbers such as compounds. Of these, organic ultraviolet absorbers are preferred, and benzotriazole compounds are more preferred. By selecting an organic ultraviolet absorber, transparency and mechanical properties are improved.

  Specific examples of the benzotriazole compound include, for example, 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, 2- [2′-hydroxy-3 ′, 5′-bis (α, α-dimethylbenzyl). ) Phenyl] -benzotriazole, 2- (2′-hydroxy-3 ′, 5′-di-tert-butyl-phenyl) -benzotriazole, 2- (2′-hydroxy-3′-tert-butyl-5 ′) -Methylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3 ', 5'-di-tert-butyl-phenyl) -5-chlorobenzotriazole), 2- (2'-hydroxy-3 ', 5'-di-tert-amyl) -benzotriazole, 2- (2'-hydroxy-5'-tert-octylphenyl) benzotriazole, 2,2′-methylenebis [4- (1,1,3,3-tetramethylbutyl) -6- (2N-benzotriazol-2-yl) phenol] and the like, among others, 2- (2′- Hydroxy-5'-tert-octylphenyl) benzotriazole, 2,2'-methylenebis [4- (1,1,3,3-tetramethylbutyl) -6- (2N-benzotriazol-2-yl) phenol] And 2- (2′-hydroxy-5′-tert-octylphenyl) benzotriazole is particularly preferable.

  The content of the ultraviolet absorber is preferably 0.05 parts by mass or more, more preferably 0.1 parts by mass or more with respect to 100 parts by mass of the (A) transparent thermoplastic resin, and the upper limit is preferably 1 part by mass or less, more preferably 0.5 part by mass or less. If the content of the ultraviolet absorber is less than the lower limit of the range, the effect of improving the weather resistance may be insufficient, and if the content of the ultraviolet absorber exceeds the upper limit of the range, the mold Debogit etc. may occur and cause mold contamination. In addition, 1 type may contain the ultraviolet absorber and 2 or more types may contain it by arbitrary combinations and a ratio.

Flame retardant Examples of the flame retardant include halogen-based, phosphorus-based, silicone-based, nitrogen-based, metal salt-based flame retardants, and the like, and any known amount can be blended in a necessary amount.
For example, when a polycarbonate resin is used as the transparent thermoplastic resin, condensed phosphate ester, phosphazene, silicone compound, sulfonic acid metal salt, polytetrafluoroethylene and the like are preferably used. The resin composition which has desired flame retardance can be obtained by using these individually or in combination of multiple types.

  When the flame retardant is a sulfonic acid metal salt, a silicone compound, or polytetrafluoroethylene, the content of the flame retardant is preferably 0.01 parts by mass or more with respect to 100 parts by mass of the (A) transparent thermoplastic resin. More preferably, it is 0.03 mass part or more, and the upper limit becomes like this. Preferably it is 5 mass parts or less, More preferably, it is 2 mass parts or less. When the flame retardant is a condensed phosphate ester or phosphazene, it is preferably 1 part by mass or more, more preferably 5 parts by mass or more, and the upper limit is preferably 100 parts by mass of the transparent thermoplastic resin (A). Is 30 parts by mass or less, more preferably 15 parts by mass or less. When the flame retardant content is less than the lower limit of the above range, it is difficult to obtain an effect of improving flame retardancy, and when it exceeds the upper limit, mechanical strength, heat and humidity resistance, thermal stability, etc. may be reduced. is there. In addition, 1 type may be contained for a flame retardant, and 2 or more types may be contained by arbitrary combinations and ratios.

[Production of resin composition]
There is no particular limitation on the method for producing the thermoplastic resin composition of the present invention, for example,
(I) (A) 0.1 to 20 parts by mass of (B) inorganic phosphor and (C) 0.001 to 3 parts by mass of fatty acid amide, and further, as desired, with respect to 100 parts by mass of the transparent thermoplastic resin. Or (ii) (A) 100 parts by mass of the transparent thermoplastic resin (B) Inorganic phosphor 0.1 to 20 parts by mass, and if necessary, (C) a method of externally adding a fatty acid amide to a thermoplastic resin composition pellet obtained by blending a desired additive and the like and melt-kneading,
Is preferably adopted. (C) Adding fatty acid amide externally means mixing (C) fatty acid amide with resin pellets using a blender mixer, tumbler mixer, or the like before or at the time of charging the resin pellets into the hopper of the molding machine. That is.

  There is no limitation on the method for producing a thermoplastic resin composition by melt-kneading, and a known method for producing a thermoplastic resin composition (pellet) can be widely adopted, and the above-described components and blended as necessary. Other components are mixed in advance using various mixers such as tumblers and Henschel mixers, and then melt-kneaded with a mixer such as a Banbury mixer, roll, brabender, single-screw kneading extruder, twin-screw kneading extruder, or kneader. The method of doing is mentioned. Among them, it is preferable to use a single-screw kneading extruder and a twin-screw kneading extruder because of excellent productivity. The material and structure of the screw or cylinder can be selected as appropriate, and the raw materials may be charged from the base of the kneading extruder or a part or all of the raw materials may be charged from the middle of the kneading extruder. The temperature for melt kneading is not particularly limited, but in the case of a polycarbonate resin composition, it is usually in the range of 240 to 320 ° C.

In the present invention, it is particularly preferable to employ the method (ii) above to produce a thermoplastic resin composition because it becomes easier to provide a molded product with reduced discoloration and appearance defects. In the method (ii), when (C) the fatty acid amide is externally added, if a liquid substance such as liquid paraffin is used as a spreading agent at room temperature, the externally added (C) fatty acid amide is pelleted. It is more preferable because it is difficult to desorb and classify from the surface.
In the melt-kneading, it is preferable to melt so as not to apply an excessive shearing force as much as possible. Therefore, it is preferable to select an apparatus and conditions. Excessive shearing load is not preferable because the resin composition may be changed to a dark color.

  (C) When fatty acid amide is added externally, the thermoplastic resin pellets are sheared and melted during molding to wet the cylinder inner wall and screw surface of the molding machine, and this enables smooth plasticization. It is considered a thing.

  The size and shape of the thermoplastic resin composition pellets thus obtained are not particularly limited and may be any, but usually the pellet length is 0.01 to 10 mm, preferably 1 to 1. The range is 7 mm. Even if the length is smaller or larger than this, the bite into the screw at the time of molding may be lowered, which is not preferable. Further, the shape of the pellet cross section may be a circle, or may be a flat shape such as an ellipse or an oval.

[Molding]
The obtained thermoplastic resin composition of the present invention is made into various molded products by applying various molding methods. The molding method is preferably a molding method such as an injection molding method, an extrusion molding method, a hollow molding method, an injection compression molding method, or a transfer molding method. Of these, the injection molding method is particularly preferable. In the molding process, it is preferable to melt so as not to apply an excessive shearing force as much as possible. For this purpose, it is preferable to select an apparatus and conditions. Excessive shearing force loading is not preferable because it may cause the molded product to discolor to a dark color system.

  In the case of using the injection molding method, as the molding machine, for example, a method of adopting a screw of a looser compression type so that rapid shearing is not applied to the unmelted resin can be preferably used.

In adjusting the molding conditions, it is particularly preferable to avoid plasticization and injection at a high shear rate. As conditions at the time of plasticization, measurement, and injection, for example, it is preferable to adjust the cylinder temperature, back pressure, screw rotation speed, and the like. Although it is necessary to adjust suitably according to the kind of (A) transparent thermoplastic resin to be used, for example, when (A) transparent thermoplastic resin is a polycarbonate resin, it is preferable to employ the following conditions. .
The cylinder temperature is preferably set to 240 to 320 ° C, more preferably 260 to 300 ° C. When adjusting the back pressure, it is preferably set to ¹ to ²⁰ kg / cm ² , more preferably 3 to 15 kg / cm ² . When adjusting a screw rotation speed, Preferably it sets to 30-200 rpm, More preferably, it sets to 50-150 rpm.

  By adjusting any of the molding conditions such as molding machine conditions, cylinder temperature, back pressure, screw rotation speed, etc. within the above preferred range, or by combining two or more conditions within these preferred ranges, It becomes easier to obtain a molded article having excellent appearance and free from problems of coloring and discoloration. In the present invention, among these conditions, the method of adjusting the back pressure is particularly preferable.

  The molded product thus obtained can be applied to various applications, such as electric / electronic equipment, OA equipment, information terminal equipment, machine parts, home appliances, vehicle parts, building members, various containers, leisure goods and miscellaneous goods. It can be applied to parts such as lighting equipment. Among these, it is suitable for parts such as electrical and electronic equipment, OA equipment, information terminal equipment, home appliances, and lighting equipment, and in particular, a light-transmitting cover (globe) that covers LED elements in remote phosphor lighting equipment. It is suitable for.

  Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not construed as being limited to the following examples.

The raw material components used in the following examples and comparative examples are as shown in Table 1 below.

[Examples 1-3 and Comparative Examples 1-6]
1. Blend for melt kneading (Examples 1 to 3)
A predetermined amount (parts by mass) described in Table 2 below was weighed and mixed in a tumbler mixer, except for (C) ethylenebisstearic acid amide in each component described in Table 2 below.
(Comparative Examples 1-5)
In Example 1, (C) instead of 0.01 parts by mass of ethylenebisstearic acid amide, Comparative Example 1 was a heat stabilizer, Comparative Example 2 was a release agent-1, Comparative Example 3 was calcium stearate, Comparative Example 4 In Comparative Example 5, 0.03 parts by mass of polyethylene wax was used. (C) Except for these components used in place of ethylenebisstearic acid amide, predetermined amounts (parts by mass) shown in Table 2 below were weighed and mixed with a tumbler mixer.
(Comparative Example 6)
Each component described in Table 2 below was weighed in a predetermined amount (parts by mass) described in Table 2 below and mixed with a tumbler mixer.

2. Melt kneading (conditions for pellet production)
(Examples 1-3 and Comparative Examples 1-6)
1 above. The mixture obtained by the above method is supplied from the base of a single-screw extruder “VS40” (screw pattern: full flight) manufactured by Isuzu Koki Co., Ltd., kneaded at a screw rotational speed of 75 rpm and a melt-kneading temperature of 280 ° C. The molten resin composition extruded into a shape was quenched in a water tank and pelletized using a pelletizer.

3. External addition of component (C) to pellets (Examples 1-3)
2. (C) Ethylene bis-stearic acid amide was mix | blended with the ratio of Table 2 with respect to the thermoplastic resin pellet obtained by the method of (2), and it mixed with the tumbler mixer.
(Comparative Examples 1-5)
(C) The heat stabilizer of Comparative Example 1, the release agent-1 of Comparative Example 2, the calcium stearate of Comparative Example 3, the polyethylene wax of Comparative Example 4 used in place of (C) ethylenebisstearic acid amide of Example 1 In the ratio of 0.03 parts by mass of the oxidized polyethylene wax of Comparative Example 5, respectively. It mix | blended with the thermoplastic resin pellet obtained by the method of (2), and mixed with the tumbler mixer.

4). Injection Molding The thermoplastic resin pellets obtained through the above methods 1 to 3 were dried and injection molded under the following conditions to produce the following flat plate-shaped molded product.
・ Material drying: 5 hours by hot air drying at 120 ° C. ・ Molding machine: Injection molding machine “NS40” manufactured by Nissei Plastic Industry Co., Ltd.
Molded product: 1 mm thickness x 30 mm length x 50 mm width flat plate shaped product Molding temperature: 280 ° C
・ Mold temperature: 80 ℃
-Screw rotation speed: 120rpm
・ Back pressure (gauge pressure): 5 kg / cm ²
・ Injection time: 12 sec
・ Cooling time: 15 sec

5). Characteristic Evaluation The obtained molded product was evaluated by measuring the total light transmittance and appearance by the following method.
・ Total light transmittance:
The total light transmittance (unit:%) was measured with a D65 light source using a Nippon Denshoku HAZE meter “NDH-4000”.
·appearance:
The hue of the molded product was visually evaluated, and whether or not the hue was dark was determined, and the vividness of the hue was determined and evaluated according to the following criteria.
Judgment criteria:
◯: The hue is not dark and vivid.
Δ: Slightly dark
X: It is quite dark and dark.
The above evaluation results are shown in Table 2 below.

From the results of Table 2, it can be seen that the molded products obtained from the thermoplastic resin composition of the present invention have no darkness, all have improved hue, excellent appearance, and high total light transmittance. (Examples 1-3).
On the other hand, the comparative example 6 which does not contain (C) fatty acid amide was quite dark, had a blackish appearance, and the total light transmittance was greatly reduced. Further, instead of externally adding (C) fatty acid amide, Comparative Examples 1 to 5 in which a heat stabilizer, a release agent-1, calcium stearate, and (oxidized) polyethylene wax were externally added had reduced total light transmittance. The appearance was slightly dark and the hue was better than Comparative Example 6, but the improvement effect was insufficient.

  Since the thermoplastic resin composition of the present invention is a thermoplastic resin composition that contains an inorganic phosphor and has no problem of coloring or discoloration, it is an electrical / electronic device, OA device, information terminal device, mechanical component, home appliance. Suitable for products, vehicle parts, building materials, various containers, leisure goods / miscellaneous goods, lighting equipment parts, especially light covers for LED lighting devices and light-transmitting covers for remote phosphor-type LED light-emitting devices (such as gloves) The industrial applicability is very high.

Claims (7)

  (A) A thermoplastic resin comprising 0.1 to 20 parts by weight of an inorganic phosphor and (C) 0.001 to 3 parts by weight of a fatty acid amide with respect to 100 parts by weight of a transparent thermoplastic resin. Composition.   (A) The thermoplastic resin composition according to claim 1, wherein the transparent thermoplastic resin is a polycarbonate resin.   Furthermore, the thermoplastic resin composition of Claim 1 or 2 which contains 0.01-10 mass parts of (D) light-diffusion agents with respect to 100 mass parts of (A) transparent thermoplastic resin. (C) The method for producing a thermoplastic resin composition according to any one of claims 1 to 3 fatty acid amide is externally added. The molded article formed by injection-molding the thermoplastic resin composition of any one of Claims 1-3 .   The molded article according to claim 5, which is a lighting cover. The molded article according to claim 5 or 6, which is a light-transmitting cover of a remote phosphor type LED light emitting device.