JP2021017464A - Thermoplastic resin composition, molded article and product - Google Patents

Abstract

To provide a thermoplastic resin composition which prevents adhesion of both hydrophilic dust stains and hydrophobic dust stains to a molded article.SOLUTION: There is provided a thermoplastic resin composition comprising a styrene-based resin (A), a hydrophilic copolymer (B) having a polyoxyethylene chain, a fatty acid metal sat (C) represented by the following formula (1) and a styrene-based thermoplastic elastomer (D): M(OH)y(R-COO)x (1)(wherein, R is an alkyl group or an alkenyl group having 6 to 40 carbon atoms, M is at least one metal element selected from the group consisting of aluminum, zinc, calcium, magnesium, lithium and barium, x and y each independently is an integer of 0 or more and satisfies the relation of x+y=[the valence of M].)SELECTED DRAWING: Figure 1

Description

The present invention relates to thermoplastic resin compositions, articles and products.

Molded products of styrene-based resins such as general-purpose polystyrene resin (GPPS), impact-resistant polystyrene resin (HIPS), and acrylonitrile-butadiene-styrene resin (ABS) are used for internal parts of products such as home appliances and OA equipment, housings, etc. It is used for various purposes and in various environments.

Dust stains such as dust, dust, soot, and oil smoke may adhere to these styrene-based resin molded products depending on the usage environment and usage method. If dust stains adhere to the molded product, the appearance may be deteriorated and the performance of the product may be deteriorated.

Therefore, in order to suppress the adhesion of dust stains, an attempt has been made to impart antistatic performance to a molded product of a styrene resin by using an antistatic agent.

For example, there is known a method of imparting antistatic performance to a molded product by spraying, dipping, coating or the like an antistatic agent on the surface of the molded product. However, in the method of attaching an antistatic agent to the surface of a molded product, most of the antistatic agents are water-soluble surfactants, and the antistatic agent is removed by wiping, washing, etc., and the antistatic effect is lost. There's a problem.

On the other hand, there is also known a method (kneading method) of imparting antistatic performance to a molded product of a styrene resin by blending an antistatic agent as an additive with the styrene resin. This kneading method has attracted attention in recent years because of its high antistatic effect.

Various compounds are known as antistatic agents used in the kneading method. For example, Patent Document 1 (Japanese Unexamined Patent Publication No. 2011-256293) discloses a fatty acid amide compound of aminoethylethanolamine. Patent Document 2 (Japanese Patent Laid-Open No. 58-118838) and Patent Document 3 (Japanese Patent Laid-Open No. 3-290464) disclose polyether ester amides. Patent Document 4 (Japanese Patent Laid-Open No. 2001-278985), Patent Document 5 (International Publication No. 2014/115745) and Patent Document 6 (International Publication No. 2014/148454) describe a block of olefins and a block of hydrophilic polymers. Block copolymers and the like comprising the above are disclosed, and Patent Documents 5 and 6 disclose a polyether ester-based polymer-type antistatic agent.

In addition, Patent Document 1 discloses that an alkali metal compound, an alkaline earth metal compound (for example, calcium stearate) and the like are used in combination in order to improve the antistatic effect of the fatty acid amide compound of aminoethylethanolamine. There is. Further, in Patent Document 4, in order to improve the antistatic effect of a block copolymer composed of a block of an olefin and a block of a hydrophilic polymer, an alkali metal compound such as lithium chloride, potassium acetate, or sodium dodecylbenzenesulfonate is used in combination. It is disclosed to do. Further, Patent Documents 5 and 6 disclose that an alkali metal compound such as potassium acetate or sodium dodecylbenzenesulfonate is blended with a polyether ester-based polymer-type antistatic agent.

Japanese Unexamined Patent Publication No. 2011-256293 Japanese Unexamined Patent Publication No. 58-118838 Japanese Unexamined Patent Publication No. 3-290464 Japanese Unexamined Patent Publication No. 2001-278985 International Publication No. 2014/115745 International Publication No. 2014/148454

However, although all of the above antistatic agents are effective in suppressing the adhesion of hydrophilic dust stains such as dust and dirt, they are effective in suppressing the adhesion of hydrophobic dust stains such as soot and oil smoke. , Almost no recognition. That is, no resin composition has been provided in which both hydrophilic dust stains and hydrophobic dust stains are difficult to adhere to.

Therefore, an object of the present invention is to suppress adhesion of both hydrophilic dust stains and hydrophobic dust stains to a molded product made of a thermoplastic resin composition.

Styrene resin (A) and
Hydrophilic copolymer (B) having a polyoxyethylene chain and
The fatty acid metal salt (C) represented by the following formula (1) and
A thermoplastic resin composition containing a styrene-based thermoplastic elastomer (D).

M (OH) y (R-COO) x ... (1)

(In formula (1), R is an alkyl group or an alkenyl group having 6 to 40 carbon atoms. M is at least one metal selected from the group consisting of aluminum, zinc, calcium, magnesium, lithium and barium. It is an element. X and y are independent integers of 0 or more, and satisfy the relationship of x + y = [valence of M].)

In the present invention, the styrene resin (A) is composed of a thermoplastic resin composition by blending a hydrophilic copolymer (B), a fatty acid metal salt (C) and a styrene thermoplastic elastomer (D). Adhesion of both hydrophilic dust stains and hydrophobic dust stains to the molded product can be suppressed.

It is sectional drawing which shows an example of the molded article which concerns on Embodiment 2. FIG. It is a schematic graph which shows the composition distribution in the depth direction about the example of the molded article which concerns on Embodiment 2. It is a conceptual diagram for demonstrating the thermoplastic resin composition which concerns on embodiment. It is a conceptual diagram for demonstrating the thermoplastic resin composition which concerns on embodiment. It is sectional drawing which shows an example of the air conditioner which concerns on Embodiment 3. FIG. It is a conceptual diagram for demonstrating the thermoplastic resin composition which concerns on embodiment.

Hereinafter, embodiments of the present invention will be described. In the drawings, the dimensional relationships such as length, width, thickness, and depth are appropriately changed for the purpose of clarifying and simplifying the drawings, and do not represent the actual dimensional relationships.

Embodiment 1.
The thermoplastic resin composition of the present embodiment is
Styrene resin (A) and
Hydrophilic copolymer (B) having a polyoxyethylene chain and
Fatty acid metal salt (C) and
It contains a styrene-based thermoplastic elastomer (D).

The molded product made of the thermoplastic resin composition of the present embodiment can also have better mechanical strength such as impact resistance.

<Styrene resin (A)>
The main components of the styrene resin (A) of the present embodiment include, for example, polystyrene resin (PS), impact-resistant polystyrene resin (HIPS), alkyl (meth) acrylate monomer and aromatic vinyl monomer. Copolymer (MS), Copolymer of vinyl cyanide compound and aromatic vinyl compound (AS), Copolymer of vinyl cyanide compound containing diene rubber component and aromatic vinyl compound (ABS) , Copolymer of vinyl cyanide compound containing ethylene-α olefin rubber component and aromatic vinyl compound (AES), Copolymer of vinyl cyanide compound containing acrylic rubber component and aromatic vinyl compound (ASA), Copolymer (MBS) of alkyl (meth) acrylate monomer containing diene rubber component and aromatic vinyl compound, alkyl (meth) acrylate monomer containing diene rubber component, vinyl cyanide compound and aromatic Examples thereof include a copolymer (MABS) with a vinyl compound, a copolymer (MAS) of an alkyl (meth) acrylate monomer containing an acrylic rubber component and an aromatic vinyl compound, and the like.

The main component is the component having the largest mass, and the content of the main component in the styrene resin (A) is preferably 90% by mass or more, more preferably 95% by mass or more.

The styrene-based resin (A) may be a resin having high stereoregularity such as syndiotactic polystyrene, which is obtained by using a catalyst such as a metallocene catalyst at the time of its production. Further, the styrene resin (A) is a polymer having a narrow molecular weight distribution, a copolymer and a block copolymer, or a polymer having high stereoregularity, which is obtained by a method such as anion living polymerization or radical living polymerization. And may be a copolymer.

The polystyrene resin (PS) is a polymer obtained by polymerizing at least one kind of aromatic vinyl compound by a polymerization method such as solution polymerization, bulk polymerization, suspension polymerization, or bulk-suspension polymerization. Preferred aromatic vinyl compounds include, for example, alkyl styrene such as styrene, α-methylstyrene, methylstyrene, ethylstyrene, isopropylstyrene, tertiary butylstyrene, phenylstyrene, vinylstyrene, chlorostyrene, bromostyrene, fluorostyrene, and the like. Examples thereof include chloromethylstyrene, methoxystyrene and ethoxystyrene. These may be used alone or in combination of two or more. Of these, particularly preferable aromatic vinyl compounds are styrene, p-methylstyrene, m-methylstyrene, p-terrary butylstyrene, p-chlorostyrene, m-chlorostyrene, and p-fluorostyrene, and styrene is particularly preferable. preferable.

The molecular weight of the polystyrene resin (PS) is not particularly limited, but the polystyrene-equivalent mass average molecular weight measured by the GPC (gel permeation chromatography) method at 135 ° C. using trichlorobenzene as a solvent is preferably 100, It is 000 or more, more preferably 150,000 or more. The width of the molecular weight distribution is not limited.

Impact-resistant polystyrene resin (HIPS) is a polymer in which a rubber-like polymer made of butadiene rubber or the like is dispersed in particles in a matrix made of an aromatic vinyl polymer such as PS. HIPS can be obtained, for example, by dissolving a rubber-like polymer in a mixed solution of an aromatic vinyl monomer and an inert solvent and stirring the mixture to carry out bulk polymerization, suspension polymerization, solution polymerization and the like. Further, HIPS is, for example, a mixture obtained by dissolving a rubber-like polymer in a mixed solution of an aromatic vinyl monomer and an inert solvent, and mixing a separately obtained aromatic vinyl polymer with the polymer obtained. There may be.

In HIPS, the matrix portion composed of an aromatic vinyl polymer is not particularly limited, but the polystyrene-equivalent mass average molecular weight measured by the GPC (gel permeation chromatography) method at 135 ° C. using trichlorobenzene as a solvent is determined. It is preferably 100,000 or more, and more preferably 150,000 or more. The average particle size of the rubber-like polymer is not particularly limited, but is generally 0.4 to 6.0 μm.

As the above aromatic vinyl monomer, styrene and its derivatives (for example, o-methylstyrene, m-methylstyrene, p-methylstyrene, 2,4-dimethylstyrene, etc.) can be used, but styrene is the most. Suitable. Two or more of these monomers may be used in combination.

As the rubber-like polymer, polybutadiene, polyisoprene, styrene-butadiene copolymer and the like can be used. Examples of the polybutadiene include high cis polybutadiene having a high cis bond content and low cis polybutadiene having a low cis bond content.

Among these, polybutadiene containing 70% by mass or more of high cis polybutadiene rubber having 90 mol% or more of cis-1,4 bonds in 100% by mass of the rubber-like polymer is preferably used.

Specifically, a rubber-modified styrene-based resin obtained by using high-cis polybutadiene rubber alone, a rubber-modified styrene-based resin obtained by using a mixture of high-cis polybutadiene rubber and low-cis polybutadiene rubber, or high-cis polybutadiene rubber. 100 mass of rubber-like polymer present in the rubber-modified styrene-based resin in any of the mixture of the rubber-modified styrene-based resin obtained by using the above and the rubber-modified styrene-based resin obtained by using the locis polybutadiene rubber. It is preferable that 70% by mass or more of high cis polybutadiene rubber is contained in%. Here, the high cis polybutadiene rubber means, for example, a polybutadiene rubber containing cis-1,4 bonds in a ratio of 90 mol% or more. The low cis polybutadiene rubber means, for example, a polybutadiene rubber having a content of 1,4-cis bond in an amount of 10 to 40 mol%.

In the copolymer (MS) of the alkyl (meth) acrylate monomer and the aromatic vinyl monomer, the alkyl (meth) acrylate monomer is selected from, for example, methyl (meth) acrylate and phenyl (meth) acrylate. At least one monomer to be made. In particular, it is preferable to use methyl (meth) acrylate. The notation "(meth) acrylate" means that both methacrylate and acrylate are included.

Examples of the aromatic vinyl monomer include styrene, α-methylstyrene, o-methylstyrene, p-methylstyrene, vinylxylene, ethylstyrene, dimethylstyrene, p-tert-butylstyrene, vinylnaphthalene, and methoxystyrene. Can be used, and styrene is particularly preferable. These can be used alone or in combination of two or more.

The mass average molecular weight of the MS and the composition ratio of methyl (meth) acrylate / styrene are not particularly limited, but the mass average molecular weight is preferably 80,000 to 300,000, more preferably 100,000 to 200,000. The composition ratio of methyl (meth) acrylate / styrene is preferably 80/20 to 40/60, and more preferably 70/30 to 50/50.

In the copolymer (AS) of the vinyl cyanide compound and the aromatic vinyl compound, acrylonitrile is particularly preferably used as the vinyl cyanide compound. Further, as the aromatic vinyl compound, styrene and α-methylstyrene can be preferably used.

As for the ratio of each component in AS, when the whole is 100% by mass, the ratio of the vinyl cyanide compound is preferably 5 to 50% by mass, more preferably 15 to 35% by mass, and the aromatic vinyl compound. The ratio of is preferably 95 to 50% by mass, more preferably 85 to 65% by mass.

Further, these vinyl compounds may be mixed with the above-mentioned other copolymerizable vinyl compounds. In this case, the content ratio of the other vinyl compound is preferably 15% by mass or less in AS.

The AS may be produced by any method such as bulk polymerization, suspension polymerization, emulsion polymerization, etc., but is preferably carried out by bulk polymerization. Further, the copolymerization method may be either one-stage copolymerization or multi-stage copolymerization.

The reduced viscosity of AS is preferably 0.2 to 1.0 dL / g (20 to 100 mL / g), more preferably 0.3 to 0.5 dL / g (30 to 50 mL / g). If the reducing viscosity is less than 0.2 dL / g (20 mL / g), the impact is lowered, and if it exceeds 1.0 dL / g (100 mL / g), the workability is deteriorated.

The reduced viscosity was determined by measuring 0.25 g of a copolymer (AS) obtained by copolymerizing a vinyl cyanide compound and an aromatic vinyl compound, and dissolving the solution in 50 mL of dimethylformamide over 2 hours with an Ubbelohde viscous meter. It was measured in an environment of 30 ° C. using. The viscometer used has a solvent flow time of 20 to 100 seconds. The reduced viscosity is calculated by the following formula from the number of seconds of solvent flowing down (t ₀ ) and the number of seconds of solution flowing down (t).
Reduced viscosity (η _sp / C) = {(t / t ₀ ) -1} / 0.5

In addition, a copolymer (ABS) of a vinyl cyanide compound containing a diene rubber component and an aromatic vinyl compound, and a copolymer of a vinyl cyanide compound containing an ethylene-α olefin rubber component and an aromatic vinyl compound (AES). ), A copolymer of a vinyl cyanide compound containing an acrylic rubber component and an aromatic vinyl compound (ASA), a copolymer of an alkyl (meth) acrylate monomer containing a diene rubber component and an aromatic vinyl compound ( MBS), a copolymer (MABS) of an alkyl (meth) acrylate monomer containing a diene rubber component, a vinyl cyanide compound, and an aromatic vinyl compound, and an alkyl (meth) acrylate monomer containing an acrylic rubber component. A copolymer of a body and an aromatic vinyl compound (MAS) is a thermoplastic copolymer.

In the present embodiment, the proportion of various rubber components contained in ABS, AES, ASA, MBS, MABS and MAS is preferably 5 to 80% by mass, more preferably 8 to 50% by mass, and particularly preferably 10 to 10. It is 30% by mass.

As the vinyl cyanide compound grafted on the rubber component, acrylonitrile is particularly preferable. Further, as the aromatic vinyl compound grafted on the rubber component, styrene and α-methylstyrene can be particularly preferably used.

Further, as the alkyl (meth) acrylate monomer, methyl (meth) acrylate and ethyl (meth) acrylate can be particularly preferably used.

The ratio of the component grafted to the rubber component is preferably 20 to 95% by mass, and more preferably 50 to 90% by mass with respect to 100% by mass of the styrene resin (A).

In ABS, AES, ASA, MBS, MABS and MAS, the rubber component exists in the form of particles. The particle size of the rubber component is preferably 0.1 to 5.0 μm, more preferably 0.15 to 1.5 μm, and particularly preferably 0.2 to 0.8 μm. Here, the distribution of the particle size of the rubber component may be a single distribution or may have a plurality of peaks of two or more. Further, in the morphology of the particle size of the rubber component, the rubber particles may form a single phase, or may have a salami structure by containing an occlude phase around the rubber particles.

In addition, ABS, AES, ASA, MBS, MABS and MAS may contain a free polymer component (aromatic vinyl compound or the like) generated at the time of polymerization.

The reduction viscosity of ABS, AES, ASA, MBS, MABS and MAS (reduction viscosity at 30 ° C. determined by the method described above) is preferably 0.2 to 1.0 dL / g (20 to 100 mL / g). , More preferably 0.3 to 0.7 dL / g (30 to 70 mL / g).

The proportion (graft ratio) of the aromatic vinyl compound or the like grafted on the rubber component is preferably 20 to 200% by mass, more preferably 20 to 70% by mass, based on the rubber component.

Further, ABS, AES, ASA, MBS, MABS and MAS may be produced by any of bulk polymerization, suspension polymerization and emulsion polymerization. In particular, ABS is preferably produced by bulk polymerization. As typical massive polymerization methods, for example, the continuous massive polymerization method (so-called Toray method) described in Chemical Engineering Vol. 48, No. 6, p. 415 (1984), Chemical Engineering Vol. 53, No. 6, p. 423 ( The continuous massive polymerization method (so-called Mitsui Toatsu method) described in 1989) and the like can be mentioned.

In the present embodiment, ABS, AES, ASA, MBS, MABS and MAS can all be suitably used as the styrene resin (A). Further, the copolymerization method may be one-step copolymerization or multi-step copolymerization. Further, ABS, AES, ASA, MBS, MABS and MAS obtained by such a production method are blended with a vinyl compound polymer obtained by separately copolymerizing an aromatic vinyl compound and a vinyl cyanide component or the like. The resin can also be preferably used as the styrene resin (A).

For AS, ABS, AES, ASA, MBS, MABS and MAS, it is preferable that the content of the alkali (earth) metal is low from the viewpoint of good thermal stability and hydrolysis resistance. The content of the alkali (earth) metal in the styrene resin (A) is preferably less than 100 ppm, more preferably less than 80 ppm, still more preferably less than 50 ppm, and particularly preferably less than 10 ppm. As described above, the massive polymerization method is preferably used from the viewpoint of reducing the content of the alkali (earth) metal.

When an emulsifier is used in AS, ABS and the like in relation to such good thermal stability and hydrolysis resistance, the emulsifier is preferably sulfonates, more preferably alkyl sulfonates. When a coagulant is used, sulfuric acid or an alkaline earth metal salt of sulfuric acid is preferable as the coagulant.

The rubber components contained in ABS, AES, ASA, MBS, MABS and MAS include polybutadiene, polyisoprene, diene-based copolymers, copolymers of ethylene and α-olefin, and ethylene and unsaturated carboxylic acid esters. Examples thereof include copolymers, copolymers of ethylene and aliphatic vinyl (for example, ethylene-vinyl acetate copolymers), non-conjugated dienter polymers of ethylene and propylene, acrylic rubbers, silicone rubbers and the like.

Examples of the diene-based copolymer include a random copolymer and block copolymer of styrene-butadiene, an acrylonitrile-butadiene copolymer, and a copolymer of (meth) acrylic acid alkyl ester and butadiene.

Examples of the copolymer of ethylene and α-olefin include ethylene-propylene random copolymer and block copolymer, ethylene-butene random copolymer and block copolymer and the like.

Examples of the copolymer of ethylene and unsaturated carboxylic acid ester include ethylene-methacrylate copolymer and ethylene-butyl acrylate copolymer.

Examples of the non-conjugated dienter polymer of ethylene and propylene include an ethylene-propylene-hexadiene copolymer.

Examples of the acrylic rubber include polybutyl acrylate, poly (2-ethylhexyl acrylate), and a copolymer of butyl acrylate and 2-ethylhexyl acrylate.

As the silicone-based rubber, for example, an IPN type rubber composed of a polyorganosiloxane rubber, a polyorganosiloxane rubber component and a polyalkyl (meth) acrylate rubber component (that is, a structure in which the two rubber components are intertwined with each other so as not to be separated). , IPN type rubber composed of a polyorganosiloxane rubber component and a polyisobutylene rubber component, and the like.

The rubber component is preferably selected from the group consisting of polydiene rubber (polybutadiene and the like), acrylic rubber, and ethylene-propylene rubber. The glass transition temperature of the rubber component is typically, for example, −10 ° C. to −20 ° C. for acrylic rubber, −50 ° C. to −58 ° C. for ethylene-propylene rubber, and about −50 ° C. to −58 ° C. for butadiene rubber. -100 ° C.

The content of the rubber component in ABS, AES, ASA, MBS, MABS and MAS used in this embodiment is preferably 4% by mass to 25% by mass. The content of the rubber component can be adjusted, for example, by adjusting the amount of the rubber component at the time of copolymerization. Further, for example, the content of the rubber component can be adjusted by mixing the aromatic vinyl copolymer containing the rubber component and the aromatic vinyl polymer or the copolymer not containing the rubber component. is there.

<Hydrophilic copolymer (B)>
The hydrophilic copolymer (B) has a polyoxyethylene chain. Since the polyoxyethylene chain functions as a hydrophilic segment, having the polyoxyethylene chain exhibits antistatic performance and suppresses the adhesion of hydrophilic dust stains.

Examples of the hydrophilic copolymer (B) include a hydrophilic copolymer (B1) in which a polyolefin and a hydrophilic polymer having a polyoxyethylene chain are repeatedly and alternately bonded to each other, a polyether ester amide, and the like.

The hydrophilic copolymer (B) preferably contains the above-mentioned hydrophilic copolymer (B1). In other words, the hydrophilic copolymer (B1) is a copolymer having a plurality of blocks derived from polyolefin and a plurality of blocks derived from a hydrophilic polymer having a polyoxyethylene chain alternately. By using the hydrophilic copolymer (B1), the antifouling effect of the thermoplastic resin composition (molded product) is further enhanced.

The hydrophilic copolymer (B) having a polyoxyethylene chain (particularly, the above-mentioned hydrophilic copolymer (B1)) has a higher heat when mixed with the styrene resin (A) than other hydrophilic polymers or antistatic agents. It is characterized by easily gathering on the surface of a molded product made of a plastic resin composition. That is, the hydrophilic copolymer (B) having a polyoxyethylene chain is present in a large amount on the surface of the molded product without being embedded in the molded product, as compared with other hydrophilic polymers and antistatic agents. Therefore, the antifouling effect is efficiently exhibited with respect to the amount of the hydrophilic copolymer (B) having a polyoxyethylene chain added. Therefore, the amount of the hydrophilic copolymer (B) required to obtain the same antifouling performance may be smaller than that of other hydrophilic polymers.

Hydrophilic copolymers (B1) in which polyolefins and hydrophilic polymers having polyoxyethylene chains are repeatedly and alternately bonded are described in, for example, JP-A-2001-278985 and JP-A-2003-48990. It can be obtained by acid-denaturing polypropylene or polyethylene and reacting it with polyalkylene glycol.

Further, the polyether ester amide is a block-type copolymer having a polyoxyethylene chain as a hydrophilic segment, and can be obtained, for example, by the methods described in JP-A-49-8472 and JP-A-6-287547. it can.

The mass average molecular weight of the polyoxyethylene chain is preferably 1,000 to 15,000 from the viewpoint of heat resistance and reactivity with the polyolefin chain.

Since the hydrophilic copolymer (B) of the present embodiment exhibits an effect of suppressing adhesion to hydrophilic dust stains by being dispersed in the thermoplastic resin composition, the surface resistance value of the hydrophilic copolymer (B) itself is high. Usually, it is preferable to be as low as possible. The surface resistance value of the hydrophilic copolymer (B) is preferably 1 × 10 ⁴ to 1 × 10 ¹⁰ Ω, and more preferably 1 × 10 ⁴ to 1 × 10 ⁷ Ω.

For the purpose of improving the effect of suppressing adhesion to hydrophilic dust stains, the thermoplastic resin composition may further contain an antistatic agent other than the above-mentioned hydrophilic polymer. Examples of other antistatic agents include surfactants (anionic surfactants, cationic surfactants, nonionic surfactants, amphoteric surfactants, etc.), ionic liquids, and the like.

In addition, the hydrophilic copolymer (B) having a polyoxyethylene chain also has another special effect.

In order to obtain amphoteric (hydrophilic and hydrophobic) antifouling properties, both a hydrophilic copolymer (B) and a fatty acid metal salt (C) described later are required, but the fatty acid metal salt (C) is hydrophilic. Since the molecular weight is smaller than that of the copolymer (B) and the entanglement with the styrene resin (A) is small, it may fall off from the surface of the molded product or deteriorate. However, a large amount of the hydrophilic copolymer (B) is present on the surface of the molded product, and the fatty acid metal salt (C) is added to the hydrophilic group of the hydrophilic copolymer (B) which prevents the adhesion of hydrophilic dust stains by the antistatic effect. By adhering the hydrophilic group, the fatty acid metal salt (C) can be stably present on the surface without falling off.

On the opposite side of the hydrophilic group of the fatty acid metal salt (C), there is R, which is a non-polar hydrophobic group of the fatty acid metal salt (C), so that it has a high adhesion suppressing effect on hydrophobic dust stains. A new effect that cannot be obtained by B) alone can be obtained.

That is, the hydrophilic copolymer (B) having a polyoxyethylene chain and the fatty acid metal salt (C) are both present on the surface of the molded product and exert a synergistic effect with each other, thereby highly suppressing adhesion to dust stains of both sexes. The effect (antifouling property) is exhibited.

<Fatty acid metal salt (C)>
The fatty acid metal salt (C) is a compound represented by the following formula (1).

M (OH) y (R-COO) x ... (1)

(In formula (1), R is an alkyl group or an alkenyl group having 6 to 40 carbon atoms. M is at least one metal selected from the group consisting of aluminum, zinc, calcium, magnesium, lithium and barium. It is an element. X and y are independent integers of 0 or more, and satisfy the relationship of x + y = [valence of M].)

Only by using the above-mentioned hydrophilic polymer or antistatic agent as an additive, the effect of suppressing the adhesion of hydrophilic dust stains can be obtained, but the effect of suppressing the adhesion of hydrophobic dust stains is low, and a comparative example described later In this case, the amount of hydrophobic dust adhered is not less than half, so new means are required.

In addition, additives that generally have water and oil repellency effects include silicone oil, fluororesin such as PTFE, and hydrophobic silica such as fumed silica, but all of these additives are hydrophobic dust. The effect of suppressing the adhesion of dirt was not obtained either. This is because when added to the resin, it is buried inside the resin and the above-mentioned additive does not appear on the surface. A fatty acid metal salt (C) is blended with a styrene resin (A) and a hydrophilic copolymer (B) as a material that can be present on the surface at a high concentration and has hydrophobicity and water / oil repellency. By doing so, the problem can be solved.

The fatty acid metal salt used in this embodiment is a fatty acid metal salt represented by the formula (1).

M (OH) y (R-COO) x ... (1)

(In formula (1), R is an alkyl group or an alkenyl group having 6 to 40 carbon atoms. M is at least one metal selected from the group consisting of aluminum, zinc, calcium, magnesium, lithium and barium. It is an element. X and y are independent integers of 0 or more, and satisfy the relationship of x + y = [valence of M].)

In the formula (1), the carbon number of R is 6 to 40, preferably 11 to 27, and more preferably 15 to 20. When the carbon number of R is smaller than 6, or when the carbon number is larger than 40, the effect of preventing the adhesion of dust becomes small, which is not preferable. Further, R is an alkyl group or an alkenyl group, preferably an alkyl group.

Generally, when the contact angle with water is higher than that of petroleum or mineral oil, it is said to have water and oil repellency, and when the contact angle with water is higher than 90 degrees, it is said to be hydrophobic. The fatty acid metal salt (C) corresponds to this.

(Metal element M)
In formula (1), M is at least one metal element selected from the group consisting of aluminum, zinc, calcium, magnesium, lithium and barium.

M is preferably at least one metal element selected from aluminum and zinc. In this case, the thermoplastic resin composition can exhibit higher antifouling performance. Further, M is more preferably aluminum. In this case, the thermoplastic resin composition can exhibit even higher antifouling performance.

With reference to FIG. 3, when the ionic radius of M is small (FIGS. 3 (a1) and (a2)), the heat is higher than when the ionic radius of M is large (FIGS. 3 (b1) and (b2)). This is because the non-polar groups (hydrophobic groups) of the fatty acid metal salt can be densely arranged on the surface of the molded product made of the plastic resin composition. When the hydrophobic groups become dense, the effect of suppressing the adhesion of hydrophobic dust stains is enhanced. The ionic radii of M are 54 for aluminum, 74 for zinc, 100 for calcium, and 135 for barium, respectively, with aluminum being the smallest and zinc being the smallest. Therefore, in order to enhance the antifouling effect, aluminum is the most suitable as the metal element M, followed by zinc.

(fatty acid)
Examples of the fatty acid constituting the fatty acid metal salt (C) of the present embodiment include caproic acid, caproic acid, lauric acid, palmitic acid, stearic acid, behenic acid, lignoceric acid, montanic acid, oleic acid, linoleic acid and the like. Can be mentioned. The fatty acid is preferably a long chain fatty acid (fatty acid having 12 or more carbon atoms) such as stearic acid, behenic acid, and montanic acid. In particular, stearic acid is more preferable for production because it is easily available and inexpensive.

Examples of the fatty acid metal salt (C) include zinc stearate, zinc 12-hydroxystearate, zinc laurate, zinc oleate, zinc 2-ethylhexarate, aluminum tristearate, and aluminum monostearate (dihydroxy). Examples thereof include aluminum distearate (hydroxy), aluminum 12-hydroxystearate, aluminum laurate, aluminum oleate, and aluminum 2-ethylhexanoate. The fatty acid metal salt (C) is preferably zinc stearate, aluminum tristearate, aluminum monostearate (dihydroxy), and aluminum distearate (hydroxy), and more preferably aluminum distearate (hydroxy). is there. The fatty acid metal salt (C) may be used alone or in combination of two or more.

Aluminum stearate, zinc stearate, calcium stearate, and barium stearate are characterized by smoothness, high water repellency, and low surface free energy (approximately 21.2 mN / m). A material having a low surface free energy has a stable surface state such as fluororesin (surface free energy: about 21.5 mN / m), so that dirt does not easily adhere to it. By forming a layer of aluminum stearate having a low surface free energy on the surface of a molded product made of a thermoplastic resin composition, the effect of preventing the adhesion of hydrophobic dust stains such as carbon black, soot, and oil smoke is exhibited. Further, since the surface free energy is lowered, hydrophilic dust stains such as dust, dust, and soil are less likely to adhere. Therefore, in addition to the static elimination effect of the hydrophilic copolymer (B) blended in the thermoplastic resin composition, the antifouling property against hydrophobic dust stains and hydrophilic dust stains is further improved.

(Valence)
In the formula (1), x and y are independent integers of 0 or more, and satisfy the relationship of x + y = [valence of M].

When the valence of M is 1, y is 0, but when the valence of M is 2 or more, y is 0 or an integer of 1 or more. When the valence of M is 3 or more, y is preferably 1. In this case, the thermoplastic resin composition can exhibit higher antifouling performance.

As an example, aluminum stearate, which is a long chain fatty acid salt of aluminum having a valence of M of 3, will be described.

As aluminum stearate, monotype aluminum monostearate containing one stearic acid [Al (C ₁₇ H ₃₅ COO) (OH) ₂ ] and ditype aluminum distearate containing two stearic acid [Al (C ₁₇₎ There are H ₃₅ COO) ₂ (OH)] and tritype aluminum tristearate [Al (C ₁₇ H ₃₅ COO) ₃ ] containing three stearic acids.

With reference to FIG. 4, aluminum tristearate is difficult to migrate to the surface of the molded product due to the large amount of non-polar groups (FIG. 4A), and is an unstable substance, so that the moisture in the air Hydrolyzes to form a mixture with aluminum monostearate or aluminum distearate. Therefore, in the case of aluminum distearate, it is easier to migrate to the surface of the molded product (FIG. 4B), and the dust suppressing effect of both sexes is higher than that of aluminum tristearate. Similarly, even when the valence of M is more than 3, the ditype fatty acid metal salt having a smaller number of fatty acids than the tritype has a higher effect of suppressing dust of both sexes.

On the other hand, aluminum monostearate has a smaller number of R, which is a non-polar group (hydrophobic group), than aluminum distearate when the number of aluminum is the same (FIG. 4 (c)). Therefore, the case of aluminum distearate has a higher effect of suppressing amphoteric dust than aluminum monostearate.

When the vicinity of the surface of the molded product was actually measured using time-of-flight secondary ion mass spectrometry (TOF-SIMS), C ₁₈ H ₃₅ O ₂ ⁻ derived from stearic acid was detected as a secondary ion. Since the detection depth of TOF-SIMS is generally 1 to 2 nm, it was confirmed that stearic acid is present on the outermost surface of the molded product.

The secondary ion intensity ratio of C ₁₈ H ₃₅ O ₂ ^{− based on} the ion intensity of C ₂ H ⁻ , which is the main peak in polystyrene analysis, is 0.341 in the case of a molded product using aluminum distearate. This was 2 to 4 times or more as compared with the case of the molded product using aluminum monostearate (0.0687) and the case of the molded product using aluminum tristearate (0.172). Therefore, in the molded product using aluminum distearate having y = 1, many non-polar groups (hydrophobic groups) are present on the surface, and the dust suppressing effect is most likely to be exhibited.

For the same reason as in the case where the valence of M is 3 or more, the ditype fatty acid metal salt suppresses the dust of both sexes more than the monotype fatty acid metal salt even when the valence of M is 2. Highly effective. Therefore, when the valence of M is 2, y is preferably 0 (x is 2).

<Styrene-based thermoplastic elastomer (D)>
The styrene-based thermoplastic elastomer (D) of the present invention is preferably a block copolymer represented by the following general formula (I) or (II).

X- (YX) n ... (I)

(XY) n ... (II)

In the general formulas (I) and (II), X is an aromatic vinyl polymer block, and Y is a polymer block different from X. n is an integer of 1 or more. In addition, in the general formula (I), the degree of polymerization may be the same or different in each block.

Here, the "aromatic vinyl polymer block" is a block made of a polymer mainly composed of vinyl aromatic hydrocarbons. The aromatic vinyl polymer block is, for example, a block made of a copolymer of a vinyl aromatic hydrocarbon and other polymerization components, or a block made of a polymer containing only a vinyl aromatic hydrocarbon. When the aromatic vinyl polymer block is a block composed of a copolymer of a vinyl aromatic hydrocarbon and other polymerization components, the ratio of the vinyl aromatic hydrocarbon is preferably 60% by mass or more.

Specific examples of vinyl aromatic hydrocarbons include styrene, o-methylstyrene, p-methylstyrene, p-tert-butylstyrene, 1,3-dimethylstyrene, α-methylstyrene, vinylnaphthalene, vinylanthracene, and the like. Examples thereof include 1,1-diphenylethylene, but the present invention is not particularly limited thereto. Among these, styrene and p-methylstyrene are preferable. These can be used alone or in combination of two or more.

In the general formula (I) or (II), Y is, for example, a butadiene polymer block, an isoprene polymer block, a butadiene / isoprene copolymer block, a hydrogenated butadiene polymer block, or a hydrogenated isoprene weight. From coalesced blocks, hydrogenated butadiene / isoprene copolymer blocks, partially hydrogenated butadiene polymer blocks, partially hydrogenated isoprene polymer blocks, and partially hydrogenated butadiene / isoprene copolymer blocks. At least one species selected from the group of

Specific examples of the block copolymer represented by the general formula (I) or (II) include styrene-ethylene / butylene-styrene copolymer, styrene-ethylene / propylene-styrene copolymer, and styrene-ethylene. Ethylene-propylene-styrene copolymer, styrene-butadiene-butene-styrene copolymer, styrene-butadiene-styrene copolymer, styrene-isoprene-styrene copolymer, styrene-hydrogenated butadiene diblock copolymer, styrene -Hydrogenized isoprenic block copolymer, styrene-butadiene diblock copolymer, styrene-isopregen block copolymer and the like can be mentioned. Among them, styrene-butadiene block copolymers and styrene-butadiene-styrene copolymers are the most suitable.

The styrene-based thermoplastic elastomer (D) preferably contains a modified styrene-based thermoplastic elastomer obtained by graft-modifying the styrene-based thermoplastic elastomer with an unsaturated carboxylic acid or a derivative thereof.

Examples of unsaturated carboxylic acids include unsaturated dicarboxylic acids and unsaturated monocarboxylic acids.

Examples of unsaturated dicarboxylic acids include maleic acid, fumaric acid, tetrahydrophthalic acid, itaconic acid, citraconic acid and the like.

Examples of unsaturated monocarboxylic acids include acrylic acid, methacrylic acid, crotonic acid, and isocrotonic acid.

Examples of the derivative of the unsaturated carboxylic acid include an acid anhydride of the unsaturated carboxylic acid, an acid halide compound, an amide compound, an imide compound, and an ester compound.

Specific examples of unsaturated carboxylic acid derivatives include maleic anhydride, maleyl chloride, maleimide, itaconic anhydride, glutaconic anhydride, citraconic anhydride, aconitic anhydride, hymic anhydride, monomethyl maleate, dimethyl maleate, and glycidyl. Maleic anhydride and the like.

Among these unsaturated carboxylic acids or derivatives thereof, unsaturated dicarboxylic acid or acid anhydride thereof is preferable, maleic acid or acid anhydride thereof is more preferable, and acid anhydride of maleic acid (maleic anhydride) is further preferable.

Since the unsaturated dicarboxylic acid or its acid anhydride functions as a compatibilizer, the hydrophilic copolymer (B) is widely dispersed, and the effect of suppressing the adhesion of dust stains is improved as an effect different from the strength improvement.

Further, when the unsaturated carboxylic acid or a derivative thereof is an unsaturated dicarboxylic acid or an acid anhydride thereof, the effect of improving the hue can be obtained as compared with the case where the unsaturated carboxylic acid or a derivative thereof is an unsaturated carboxylic acid or a derivative thereof.

Further, when the unsaturated carboxylic acid or its derivative is an unsaturated dicarboxylic acid or an acid anhydride thereof, the adhesion of dust stains is suppressed with a small amount of addition as compared with the case where the unsaturated carboxylic acid or its derivative is another unsaturated carboxylic acid or its derivative. An effect (antifouling effect) can be obtained. Further, when the unsaturated carboxylic acid or a derivative thereof is maleic acid or an acid anhydride thereof, a higher antifouling effect can be obtained. Further, when the unsaturated carboxylic acid or a derivative thereof is an acid anhydride of maleic acid, the hydrophilic block polymer (B) has good dispersibility and has the highest antifouling effect.

The graft modified product (group modified product) of the styrene-based thermoplastic elastomer includes, for example, a polymer block mainly composed of at least one vinyl aromatic hydrocarbon and a polymer block mainly composed of at least one conjugated diene. A composition prepared by mixing a block copolymer containing, with an acid anhydride group-containing compound and a peroxide compound is supplied to a single-screw or twin-screw extruder, heated, melted, and kneaded. Can be obtained by The mixing can be performed by, for example, a kneader (kneader, Banbury mixer, roll, etc.), a mixer (ribbon blender, Henschel mixer, etc.) or the like.

The amount of the acid anhydride group added to the styrene-based thermoplastic elastomer can be determined by, for example, an infrared spectroscopic analysis method and a calibration curve method based on the absorption derived from the acid anhydride group in the vicinity of 1790 cm- ^1. ..

In the styrene-based thermoplastic elastomer to which the acid anhydride group is added, the addition ratio of the acid anhydride group is preferably 0.5 to 5% by mass. In the range of 0.5 to 5% by mass, the hue of the thermoplastic resin composition and its molded product tends to be good.

The content of the rubber component in the styrene-based thermoplastic elastomer is usually 75 to 25% by mass. One or more types of styrene-based thermoplastic elastomer (D) can be selected and used. When two or more types of styrene-based thermoplastic elastomers are used, their constituent components may be the same or different.

The mass average molecular weight of the styrene-based thermoplastic elastomer is preferably 250,000 or less, more preferably 200,000 or less, still more preferably 150,000 or less. If the mass average molecular weight exceeds 250,000, the compatibility improving effect may be reduced. The lower limit of the mass average molecular weight is not particularly limited, but the mass average molecular weight is preferably 40,000 or more, more preferably 50,000 or more. The mass average molecular weight can be calculated by measuring the molecular weight in terms of polystyrene with a gel permeation chromatograph.

<Contents of each component>
In the thermoplastic resin composition of the present embodiment, the blending amount of the hydrophilic copolymer (B) is preferably 1 to 20 parts by mass, more preferably 1 part by mass, based on 100 parts by mass of the styrene resin (A). ~ 17 parts by mass.

The amount of the fatty acid metal salt (C) to be blended is preferably 0.5 to 10 parts by mass, and more preferably 1 to 8 parts by mass with respect to 100 parts by mass of the styrene resin (A).

The amount of the styrene-based thermoplastic elastomer (D) to be blended is preferably 0.5 to 20 parts by mass, and more preferably 1 to 15 parts by mass with respect to 100 parts by mass of the styrene-based resin (A). ..

The thermoplastic resin composition of the present embodiment particularly comprises 100 parts by mass of the styrene resin (A), 1 to 20 parts by mass of the hydrophilic copolymer (B), and 0.5 to 10 parts by mass of the fatty acid metal salt (C). It is preferable to contain 0.5 to 20 parts by mass of the styrene-based thermoplastic elastomer (D).

The fatty acid metal salt (C) is generally blended in a thermoplastic resin composition in an amount of 0.5% by mass or less (particularly about 0.1%) as a lubricant, a mold release agent, etc. for improving moldability. In some cases, by blending more than 0.5% by mass of the fatty acid metal salt (C), both the hydrophilic copolymer (B) and the fatty acid metal salt (C) are concentrated on the surface of the molded product at a high concentration. The action of making it exist is exerted, and the antifouling effect of both sexes is further improved.

When the blending amount of the hydrophilic copolymer (B) exceeds 20 parts by mass, the mechanical strength such as elastic modulus decreases, and when it is less than 1 part by mass, the effect of suppressing the adhesion of dust is observed. become.

When the amount of the fatty acid metal salt (C) is more than 10 parts by mass, the heat resistance and impact resistance are lowered, and when it is less than 0.5 parts by mass, the effect of suppressing dust adhesion is lowered. Will be able to.

As described above, the fatty acid metal salt (C) is generally used for a purpose different from the object of the present embodiment, which is to suppress the adhesion of amphoteric dust stains of hydrophilic dust stains and hydrophobic dust stains. There are times. It is used, for example, as a lubricant, a molding improver, a mold release agent, an anti-fog agent, etc., as disclosed in JP-A-2004-168555, JP-A-2003-183529, and the like. In this case, the blending amount of the fatty acid metal salt (C) is less than 0.5 parts by mass with respect to 100 parts by mass of the styrene resin (A). Furthermore, it is 0.1 parts by mass or less in general usage related to the manufacturing industry. Further, the effect of suppressing the adhesion of dust of the fatty acid metal salt (C) has not been known so far.

In the present embodiment, for a purpose completely different from the conventional usage, in order to obtain the effect of suppressing the adhesion of both hydrophilic dust stains and hydrophobic dust stains, a fatty acid metal salt (more than a generally used amount) It has been found that the effect of suppressing adhesion to dust stains of both sexes can be obtained for the first time by sufficiently increasing the amount of C). Therefore, the blending amount of the fatty acid metal salt (C) is preferably 0.5 parts by mass or more, and more preferably 1 to 8 parts by mass with respect to 100 parts by mass of the styrene resin (A). In this case, a good dust suppression effect equal to or higher than that obtained by coating the surface of the molded product with dust suppression coating can be obtained. No example has been known so far in which 1 part by mass or more of the fatty acid metal salt (C) is blended with 100 parts by mass of the thermoplastic resin for the purpose of suppressing dust.

The non-polar hydrophobic group R of the fatty acid metal salt, which is suitable for the air, has a new effect of suppressing the adhesion of hydrophobic dust stains. By adding 0.5% by mass or more of the fatty acid metal salt (C) to the styrene resin (A), many hydrophobic groups can be densely arranged on the surface of the molded product made of the thermoplastic resin composition. This makes it possible to enhance the effect of suppressing the adhesion of hydrophobic dust stains.

As will be described later, the antistatic effect of the hydrophilic copolymer (B) having a polyoxyethylene chain enhances the effect of suppressing the adhesion of hydrophilic dust stains, and the addition of the fatty acid metal salt (C) makes it hydrophobic. The effect of suppressing the adhesion of dust stains is enhanced, and a new effect that is strong against stains of both sexes can be obtained.

Therefore, the composition containing the styrene resin (A) and the hydrophilic copolymer (B) has a higher effect of suppressing the adhesion of dust stains (antifouling effect) than the styrene resin (A) alone, and the styrene resin (A). ), The hydrophilic copolymer (B), and the fatty acid metal salt (C) are more effective in suppressing the adhesion of dust stains.

When the blending amount of the styrene-based thermoplastic elastomer (D) is less than 0.5 parts by mass, the effect of improving the dispersibility of the hydrophilic copolymer (B) component in the styrene-based resin (A) is reduced, and antifouling is prevented. Deterioration of effect, impact strength improving effect, thermal stability improving effect, etc. may be observed. Further, even if the styrene-based thermoplastic elastomer (D) is blended in an amount of more than 20 parts by mass, no further effect of improving dispersibility is observed, and a decrease in elastic modulus is observed.

The thermoplastic resin composition of the present embodiment contains a styrene resin (A), a hydrophilic copolymer (B), a fatty acid metal salt (C), and a styrene thermoplastic elastomer (D). Therefore, not only the effect of suppressing adhesion to dust and dirt of both sexes can be obtained, but also the effect of improving the impact strength (effect of maintaining mechanical strength such as impact resistance) can be obtained.

<Arbitrary ingredient>
The thermoplastic resin composition of the present embodiment has, as an optional component, for example, a heat stabilizer, an ultraviolet absorber, a light stabilizer, an antibacterial agent, an antifungal agent, and an inorganic substance, as long as the object of the present embodiment is not impaired. It may contain components such as a filler.

(Heat stabilizer)
The thermoplastic resin composition of the present embodiment may contain a heat stabilizer in order to improve the heat stability during production and the like.

As the heat stabilizer, it is preferable to use a phosphorus-based stabilizer and / or a hindered phenol-based antioxidant, and it is more preferable to use these in combination.

The amount of the phosphorus-based stabilizer and / or the hindered phenol-based antioxidant added to the thermoplastic resin composition of the present embodiment is not particularly limited.

Since the effect of improving thermal stability can be effectively obtained and the blending amount of each of the above essential components is not affected, it is preferably 0.01 to 1 with respect to 100 parts by mass of the thermoplastic resin composition. It is by mass, more preferably 0.01 to 0.6 parts by mass.

Examples of the phosphorus-based stabilizer include phosphorous acid, phosphoric acid, phosphonic acid, phosphonic acid, and esters, phosphonite compounds thereof, tertiary phosphine and the like.

Examples of phosphite (phosphite compounds) include triphenylphosphite, tris (nonylphenyl) phosphite, tridecylphosphite, distearylpentaerythritol diphosphite, and bis (2,4-di-tert-butylphenyl). ) Pentaerythritol diphosphite, bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite, bis {2,4-bis (1-methyl-1-phenylethyl) phenyl} penta Examples thereof include erythritol diphosphite, phenylbisphenol A pentaerythritol diphosphite, bis (nonylphenyl) pentaerythritol diphosphite, and dicyclohexylpentaerythritol diphosphite.

As the phosphite ester (phosphite compound), in addition to the above, those having a cyclic structure by reacting with dihydric phenols can also be used.

For example, 2,2'-methylenebis (4,6-di-tert-butylphenyl) (2,4-di-tert-butylphenyl) phosphite, 2,2'-methylenebis (4,6-di-tert-). Examples thereof include butylphenyl) (2-tert-butyl-4-methylphenyl) phosphite and 2,2-methylenebis (4,6-di-tert-butylphenyl) octylphosphite.

Examples of the phosphoric acid ester (phosphate compound) include triphenyl phosphate and trimethyl phosphate.

Examples of the phosphonite compound include tetrakis (di-tert-butylphenyl) -biphenylenediphosphonite and bis (di-tert-butylphenyl) -phenyl-phenylphosphonite.

The phosphonite compound can be used in combination with the above-mentioned phosphite compound having an aryl group in which two or more alkyl groups are substituted, and is preferable.

Examples of the phosphonate ester (phosphonate compound) include dimethyl benzenephosphonate, diethyl benzenephosphonate, and dipropyl benzenephosphonate.

Examples of the tertiary phosphine include triphenylphosphine and the like.

Among the above phosphorus-based stabilizers, a phosphonite compound or a phosphite compound represented by the following general formula (2) is preferable.

(In the formula (2), R and R'represent an alkyl group having 6 to 30 carbon atoms or an aryl group having 6 to 30 carbon atoms, and may be the same or different from each other.)

As described above, the phosphonite compound is preferably tetrakis (2,4-di-tert-butylphenyl) -biphenylenediphosphonite.

More suitable phosphite compounds in the above formula (2) are distearyl pentaerythritol diphosphite, bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite, and bis (2,6-di-). tert-Butyl-4-methylphenyl) pentaerythritol diphosphite, and bis {2,4-bis (1-methyl-1-phenylethyl) phenyl} pentaerythritol diphosphite.

Examples of the hindered phenol compound include tetrakis [methylene-3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionate] methane and octadecyl-3- (3,5-di-tert-butyl-4-4). Hydroxyphenyl) propionate, and 3,9-bis [2- {3- (3-t-butyl-4-hydroxy-5-methylphenyl) propionyloxy} -1,1-dimethylethyl] -2,4,8 , 10-Tetraoxaspiro [5,5] undecane and the like.

The thermoplastic resin composition of the present embodiment may contain other thermal stabilizers other than the phosphorus-based stabilizer and the hindered phenol-based antioxidant, if necessary.

The other heat stabilizer is preferably used in combination with at least one of a phosphorus-based stabilizer and a hindered phenol-based antioxidant, and particularly preferably in combination with both.

Other heat stabilizers include lactone-based stabilizers typified by the reaction product of 3-hydroxy-5,7-di-tert-butyl-furan-2-one and o-xylene (details of this stabilizer). For reference, refer to Japanese Patent Application Laid-Open No. 7-233160).

Regarding the lactone-based stabilizer, Irganox HP-136 (registered trademark, manufactured by CIBA SPECIALTY CHEMICALS) and the like are commercially available.
Irganox HP-2921 (registered trademark, manufactured by CIBA SPECIALTY CHEMICALS) and the like are commercially available as stabilizers in which the above-mentioned lactone-based stabilizers, phosphite compounds, and hindered phenol compounds are mixed.

The amount of the lactone-based stabilizer added is preferably 0.0005 to 0.05 parts by mass, and more preferably 0.001 to 0.03 parts by mass with respect to 100 parts by mass of the thermoplastic resin composition.

Other stabilizers include sulfur-containing stabilizers such as pentaerythritol tetrakis (3-mercaptopropionate), pentaerythritol tetrakis (3-laurylthiopropionate), and glycerol-3-stearylthiopropionate. Be done.

The amount of the stabilizer other than the phosphorus-based stabilizer and / or the hindered phenol-based antioxidant in the thermoplastic resin composition of the present embodiment is not particularly limited, and is added to 100 parts by mass of the thermoplastic resin composition. On the other hand, it is preferably 0.0005 to 0.1 parts by mass, more preferably 0.001 to 0.08 parts by mass, and particularly preferably 0.001 to 0.05 parts by mass.

(UV absorber)
The thermoplastic resin composition of the present embodiment may contain an ultraviolet absorber. Since the thermoplastic resin composition of the present embodiment may be inferior in weather resistance due to the influence of the rubber component and the like, it is effective to add an ultraviolet absorber in order to improve the weather resistance.

Examples of the ultraviolet absorber of the present embodiment include a benzophenone-based ultraviolet absorber, a benzotriazole-based ultraviolet absorber, a hydroxyphenyltriazine-based ultraviolet absorber, a cyclic iminoester-based ultraviolet absorber, and a cyanoacrylate-based ultraviolet absorber. Examples include an ultraviolet absorber.

Examples of benzophenone-based ultraviolet absorbers include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 2-hydroxy-4-benzyloxybenzophenone, and 2-hydroxy. -4-methoxy-5-sulfoxybenzophenone, 2-hydroxy-4-methoxy-5-sulfoxitrihydride benzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, 2,2', 4,4'- Tetrahydroxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxy-5-sodium sulfoxybenzophenone, bis (5-benzoyl-4-hydroxy) Examples include -2-methoxyphenyl) methane, 2-hydroxy-4-n-dodecyloxybenzophenone, and 2-hydroxy-4-methoxy-2'-carboxybenzophenone.

Examples of the benzotriazole-based ultraviolet absorber include 2- (2-hydroxy-5-methylphenyl) benzotriazol, 2- (2-hydroxy-5-tert-octylphenyl) benzotriazol, and 2- (2). -Hydroxy-3,5-dicumylphenyl) phenylbenzotriazole, 2- (2-hydroxy-3-tert-butyl-5-methylphenyl) -5-chlorobenzotriazole, 2,2'-methylenebis [4-( 1,1,3,3-Tetramethylbutyl) -6- (2H-benzotriazole-2-yl) phenol], 2- (2-hydroxy-3,5-di-tert-butylphenyl) benzotriazol, 2- (2-Hydroxy-3,5-di-tert-butylphenyl) -5-chlorobenzotriazole, 2- (2-hydroxy-3,5-di-tert-amylphenyl) benzotriazol, 2-( 2-Hydroxy-5-tert-octylphenyl) benzotriazole, 2- (2-hydroxy-5-tert-butylphenyl) benzotriazole, 2- (2-hydroxy-4-octoxyphenyl) benzotriazole, 2,2'-Methylenebis (4-cumyl-6-benzotriazolephenyl), 2,2'-p-phenylenebis (1,3-benzoxazine-4-one), 2- [2-hydroxy-3-( 3,4,5,6-Tetrahydrophthalimidemethyl) -5-methylphenyl] Benzotriazole and the like can be mentioned. Examples of other benzotriazole-based ultraviolet absorbers include polymers having a 2-hydroxyphenyl-2H-benzotriazole skeleton. Examples of the polymer having a 2-hydroxyphenyl-2H-benzotriazole skeleton include 2- (2'-hydroxy-5-methacryloxyethylphenyl) -2H-benzotriazole and a vinyl-based monomer copolymerizable with the monomer. Examples thereof include a copolymer of 2- (2'-hydroxy-5-acryloxyethylphenyl) -2H-benzotriazole and a vinyl-based monomer copolymerizable with the monomer.

Examples of the hydroxyphenyltriazine-based ultraviolet absorber include 2- (4,6-diphenyl-1,3,5-triazine-2-yl) -5-hexyloxyphenol and 2- (4,6-diphenyl-). 1,3,5-Triazine-2-yl) -5-methyloxyphenol, 2- (4,6-diphenyl-1,3,5-triazine-2-yl) -5-ethyloxyphenol, 2-( 4,6-diphenyl-1,3,5-triazine-2-yl) -5-propyloxyphenol, and 2- (4,6-diphenyl-1,3,5-triazine-2-yl) -5- Examples include butyloxyphenol. Further, the phenyl groups of the compounds exemplified above, such as 2- (4,6-bis (2,4-dimethylphenyl) -1,3,5-triazine-2-yl) -5-hexyloxyphenol, are 2, Compounds substituted with 4-dimethylphenyl groups are exemplified.

Examples of the cyclic iminoester-based UV absorber include 2,2'-p-phenylene bis (3,1-benzoxazine-4-one) and 2,2'-(4,4'-diphenylene) bis ( 3,1-benzoxazine-4-one), 2,2'-(2,6-naphthalene) bis (3,1-benzoxazine-4-one) and the like can be mentioned.

Examples of the cyanoacrylate-based UV absorber include 1,3-bis-[(2'-cyano-3', 3'-diphenylacryloyl) oxy] -2,2-bis [(2-cyano-3,). Examples thereof include 3-diphenylacryloyl) oxy] methyl) propane and 1,3-bis-[(2-cyano-3,3-diphenylacryloyl) oxy] benzene.

Further, the ultraviolet absorber is a polymer-type ultraviolet absorber obtained by copolymerizing a photostable monomer having an ultraviolet absorbing monomer and / or a hindered amine structure with a monomer such as alkyl (meth) acrylate. It may be an agent. As the ultraviolet absorbing monomer, a compound which is a (meth) acrylic acid ester and contains a benzotriazole skeleton, a benzophenone skeleton, a triazine skeleton, a cyclic imino ester skeleton, and a cyanoacrylate skeleton in the ester substituent is preferable. Illustrated.

Among the above, benzotriazole-based and hydroxyphenyltriazine-based UV absorbers are preferable in terms of UV absorption ability, and cyclic iminoester-based and cyanoacrylate-based UV absorbers are preferable in terms of heat resistance and hue (transparency). Is preferable. The above-mentioned ultraviolet absorber may be used alone or in a mixture of two or more kinds.

The content of the ultraviolet absorber is preferably 0.01 to 2 parts by mass, more preferably 0.02 to 2 parts by mass, still more preferably 0.03 to 1 part by mass, based on 100 parts by mass of the thermoplastic resin composition. Parts, particularly preferably 0.05 to 0.5 parts by mass.

(Light stabilizer)
The thermoplastic resin composition of the present embodiment may contain a light stabilizer. Since the thermoplastic resin composition of the present embodiment may cause yellowing in a dark place, it is effective to add a light stabilizer in order to prevent such deterioration.

As such a light stabilizer, a hindered amine light stabilizer (HALS) can be preferably used. HALS is, for example, a compound represented by the following general formulas (3) to (6), and a combination of two or more of these compounds.

In the general formulas (3) to (6), R _{1 to} R ₃ are independent substituents.

Examples of the substituent include hydrogen, ether group, ester group, amine group, amide group, alkyl group, alkenyl group, alkynyl group, aralkyl group, cycloalkyl group, and aryl group.

These substituents may contain functional groups. Examples of the functional group include alcohol, ketone, anhydride, imine, siloxane, ether, carboxyl group, aldehyde, ester, amide, imide, amine, nitrile, ether, urethane, and a combination thereof.

As the hindered amine light stabilizer (HALS), a compound derived from a substituted piperidine compound is preferable, and a compound derived from an alkyl-substituted piperidyl, piperidinyl or piperazinone compound, and a substituted alkoxypiperidinyl compound is more preferable.

The hindered amine light stabilizer is, but is not limited to, for example, 2,2,6,6-tetramethyl-4-piperidone; 2,2,6,6-tetramethyl-4-piperidinol; bis. -(1,2,2,6,6-pentamethylpiperidyl)-(3', 5'-di-t-butyl-4'-hydroxybenzyl) butylmalonate; di- (2,2,6,6) -Tetramethyl-4-piperidyl) sebacate; N- (2-hydroxyethyl) -2,2,6,6-tetramethyl-4-piperidinol and succinic acid oligomer; cyanulic acid and N, N-di (2,) 2,6,6-Tetramethyl-4-piperidyl) -hexamethylenediamine oligomer; bis- (2,2,6,6-tetramethyl-4-piperidinyl) succinate; bis- (1-octyloxy-2, 2,6,6-tetramethyl-4-piperidinyl) sebacate; bis- (1,2,2,6,6-pentamethyl-4-piperidinyl) sebacate; tetrakis- (2,2,6,6-tetramethyl-) 4-Piperidyl) -1,2,3,4-butanetetracarboxylate; N, N'-bis- (2,2,6,6-tetramethyl-4-piperidyl) -hexane-1,6-diamine; N-butyl-2,2,6,6-tetramethyl-4-piperidinamine; 2,2'-[(2,2,6,6-tetramethyl-piperidinyl) -imino] -bis- [ethanol]; Poly ((6-morpholin-S-triazine-2,4-diyl) (2,2,6,6-tetramethyl-4-piperidinyl) -iminohexamethylene- (2,2,6,6-tetramethyl-) 4-Piperidinyl) -imino); 5- (2,2,6,6-tetramethyl-4-piperidinyl) -2-cyclo-undecyl-oxazole); 1,1'-(1,2-ethane-di-) Il) -bis- (3,3', 5,5'-tetramethyl-piperazinone); 8-acetyl-3-dodecyl-7,7,9,9-tetramethyl-1,3,8-triazaspiro (4) .5) Decane-2,4-dione; polymethylpropyl-3-oxy- [4 (2,2,6,6-tetramethyl) -piperidinyl] siloxane; 1,2,3,4-butane-tetracarboxylic Acid-1,2,3-tris (1,2,2,6,6-pentamethyl-4-piperidinyl) -4-tridecyl ester; α-methylstyrene-N- (2,2,6,6-tetra Methyl-4-piperidinyl) maleimide and N-stearyl Copolymer with Maleimide; 1,2,3,4-butanetetracarboxylic acid-β, β, β', β'-tetramethyl-2,4,8,10-tetraoxaspiro [5.5] undecane-3 , 9-Diethanol and 1,2,2,6,6-pentamethyl-4-piperidinyl ester copolymer; 2,4,8,10-tetraoxaspiro [5.5] undecane-3,9-diethanol Β, β, β', β'-tetramethyl-polymer with 1,2,3,4-butanetetracarboxylic acid, 2,2,6,6-tetramethyl-4-piperidinyl ester; D-glucitol, 1,3: 2,4-bis-o- (2,2,6,6-tetramethyl-4-piperidinylidene)-; 7-oxa-3,20-diazadispiro [5.1.11.2 ] -Ompartium of heneicosan-21-one-2,2,4,4-tetramethyl-20- (oxylanylmethyl); propanic acid, [(4-methoxyphenyl) methylene]-, bis (1,2) , 2,6,6-pentamethyl-4-piperidinyl) ester; formamide, N, N'-1,6-hexanediylbis [N- (2,2,6,6-tetramethyl-4-piperidinyl; 1, 3,5-triazine-2,4,6-triamine, N, N'''-[1,2-ethanediylbis [[[4,6-bis [butyl (1,2,2,6,6-pentamethyl-) 4-piperidinyl) amino] -1,3,5-triazin-2-yl] imino] -3,1-propanediyl]]-bis [N', N''-dibutyl-N', N''-bis (1,2,2,6,6-pentamethyl-4-piperidinyl); poly [[6-[(1,1,3,33-tetramethylbutyl) amino] -1,3,5-triazine-2, 4-Diyl] [(2,2,6,6-tetramethyl-4-piperidinyl) -imino] -1,6-hexanediyl [(2,2,6,6-tetramethyl-4-piperidinyl) imino] ]; 1,5-Dioxaspiro (5.5) undecane 3,3-dicarboxylic acid, bis (2,2,6,6-tetramethyl-4-piperidinyl) ester; 1,5-dioxaspiro (5.5) undecane 3,3-Dicarboxylic acid, bis (1,2,2,6,6-pentamethyl-4-piperidinyl) ester; N-2,2,6,6-tetramethyl-4-piperidinyl-N-amino-oxamid; 4-Acryloyloxy-1,2,2,6,6-pentamethyl-4-piperidin; 1,5,8,12 -Tetrakiss [2', 4'-bis (1'', 2'', 2'', 6'', 6''-pentamethyl-4''-piperidinyl (butyl) amino) -1', 3', 5'-Triazine-6'-yl] -1,5,8,12-tetraazadodecane; 3-dodecyl-1- (2,2,6,6-tetramethyl-4-piperidyl) -pyrrolidin-2, 5-dione; 1,1'-(1,2-ethane-diyl) -bis- (3,3', 5,5'-tetra-methyl-piperazinone); 1,1'1''-( 1,3,5-triazine-2,4,6-triyltris ((cyclohexylimino) -2,1-ethanediyl) tris (3,3,5-5-tetramethylpiperazinone); 1,1', 1 ''-(1,3,5-triazine-2,4,6-triyltris ((cyclohexylimino) -2,1-ethanediyl) tris (3,3,4,5,5-tetramethylpiperazinone), etc. Can be mentioned.

The amount of the hindered amine light stabilizer (HALS) added is preferably 0.01 to 5 parts by mass, more preferably 0.05 to 3 parts by mass, still more preferably 0, with respect to 100 parts by mass of the thermoplastic resin composition. It is 1 to 1 parts by mass.

(Antibacterial agent)
The thermoplastic resin composition of the present embodiment may contain an antibacterial agent. The antibacterial agent is not particularly limited, but for example, antibacterial metals such as zinc oxide, silver, copper, and zinc can be used as crystalline aluminosilicates, amorphous aluminosilicates, silica gel, activated alumina, and ceramics. Examples thereof include inorganic antibacterial agents supported on soil, activated carbon, zirconium phosphate, hydroxyapatite, magnesium oxide, magnesium perchlorate, glass and the like. Zinc oxide is preferable as the antibacterial metal.

Zinc oxide is not particularly limited and may be commercially available. For example, metallic zinc is heated and vaporized and burned in air, or zinc sulfate or zinc nitrate is heated. It may be prepared by Further, as the zinc oxide, for example, various shapes such as fibrous, plate-shaped, particle-shaped, and tetrapod-shaped can be used. The zinc oxide used in this embodiment may be surface-treated with silicon oxide, silicone oil, an organosilicon compound, an organotitanium compound, or the like.

Examples of commercially available zinc oxide include "type 1 zinc oxide", "type 2 zinc oxide", and "type 3 zinc oxide" classified by JIS K-1410, and the Japanese Pharmacopoeia. Examples thereof include zinc oxide and anisotropic (columnar, plate-shaped, tetrapot-shaped) zinc oxide (zinc oxide having shape anisotropy) prepared through a hydrothermal synthesis step. Of these zinc oxides, particulate zinc oxide having an average particle size of 50 to 200 nm is preferable, and particulate zinc oxide having an average particle size of 100 to 150 nm is particularly preferable. The average particle size referred to here is a particle size in which the integrated mass distribution is 50% in the particle size distribution obtained by measuring with a laser diffraction / scattering type particle size distribution measuring device.

The blending amount of zinc oxide is preferably 0.01 to 1 part by mass, more preferably 0.05 to 0.5 part by mass, and further preferably 0.1 to 0 with respect to 100 parts by mass of the thermoplastic resin composition. .3 parts by mass.

(Inorganic filler)
The thermoplastic resin composition of the present embodiment may contain an inorganic filler as a reinforced filler for the purpose of imparting rigidity and improving strength.

Examples of the inorganic filler include talc, wallastnite, mica, clay, montmon lilonite, smectite, kaolin, calcium carbonate, glass fiber, glass bead, glass balloon, glass milled fiber, glass flake, carbon fiber, and carbon flake. , Carbon beads, carbon milled fiber, metal flakes, metal fiber, metal coated glass fiber, metal coated carbon fiber, metal coated glass flakes, silica, ceramic particles, ceramic fiber, ceramic balloon, aramid particles, aramid fiber, polyarylate fiber, Examples thereof include various whiskers such as graphite, potassium titanate whiskers, aluminum borate whiskers, and basic magnesium sulfate. Of these, silicate-based fillers such as talc, wallastnite, mica, glass fiber, and glass milled fiber are preferably used. Of these, talc, wallastnite and mica are particularly preferred.

When an inorganic filler is blended, the thermoplastic resin composition of the present embodiment contains an additive containing an acidic group such as a carboxylic acid anhydride group or a sulfonic acid group in order to improve the wettability of the inorganic filler. Can be included.

The content of the inorganic filler in the present embodiment is preferably 0.1 to 30 parts by mass, more preferably 0.5 to 20 parts by mass, and further preferably 1 to 1 part by mass with respect to 100 parts by mass of the thermoplastic resin composition. It is 10 parts by mass. If the blending amount is less than 0.1 parts by mass, there is no reinforcing effect of the filler, and if it exceeds 30 parts by mass, the impact strength is remarkably lowered, which is not preferable.

(Other optional ingredients)
Other optional components that can be used in this embodiment include dyes, pigments, antifoaming agents, plasticizers, lubricants, mold release agents, flame retardants, and the like for coloring. Further, it is also possible to blend a thermoplastic resin other than the styrene resin (A), the hydrophilic copolymer (B) and the styrene thermoplastic elastomer (D) within a range that does not impair the object of the present embodiment.

As such a thermoplastic resin, a thermoplastic resin used in home appliances and OA equipment can be used as a general-purpose resin.

Examples of such a thermoplastic resin include
Polyolefin resins (high density polyethylene, low density polyethylene, polypropylene, etc.), cyclic olefin resins, and polyester resins (polylactic acid, polyethylene terephthalate, polybutylene terephthalate, etc.), which are olefin resins,
Polystyrene (PS resin), acrylonitrile butadiene styrene (ABS resin), and acrylonitrile styrene (AS resin), which are styrene-based resins,
ASA resin made by polymerizing acrylic rubber instead of ABS resin butadiene,
AES resin obtained by polymerizing ethylene-based rubber instead of ABS resin butadiene,
Examples thereof include methyl methacrylate butadiene styrene (MBS resin).

Examples of other general-purpose resins include polyvinyl chloride resins (polyvinyl chloride, polyvinylidene chloride, etc.), polymethylmethacrylate resins, polyvinyl alcohols, polyethylene terephthalate (PET resin), and polybutylene terephthalate (PBT resin). ..

Further, as examples of engineering plastics having particularly excellent strength and enhanced functions such as heat resistance, polycarbonate resins (BPA type polycarbonate, aliphatic polycarbonate, etc.), polyamide resins, polyphenylene ether resins (PPE resins), etc. Examples thereof include polyoxymethylene resin (polyacetal and the like), polyphenylene sulfide resin, polyetherimide resin, aromatic polyether ketone resin, polysulfone resin, polyamideimide resin and the like.

These resins may be used alone or in combination of a plurality of resins as raw materials for the thermoplastic resin composition of the present embodiment. The plurality of resins are polymer alloys such as PC / ABS and PC / AS. Such polymer alloys have the features of both polycarbonate (PC resin) and styrene resin (ABS resin, AS resin, etc.), and are used for electrical / electronic related products, OA equipment, lighting equipment, precision machinery, automobile parts, etc. Used in a wide range of fields such as household products.

Since the molecular weight of the fatty acid metal salt (C) is lower than that of the resin (A) and the hydrophilic copolymer (B) having a polyoxyethylene chain, the fatty acid metal salt (C) can be used as a raw material regardless of which resin is used as the raw material. Is easily exposed on the surface of the molded product, so that various resins can be blended into the thermoplastic resin composition.

In addition, referring to FIG. 6, the fatty acid metal salt (C) and the hydrophilic copolymer (B) have different melt viscosities at the time of molding. At the time of molding, the resin (A) injected into the mold first solidifies, then the hydrophilic copolymer (B) solidifies, and then the fatty acid metal salt (C) having a low molecular weight solidifies. That is, the hydrophilic copolymer (B) and the fatty acid metal salt (C) have a slower solidification rate than the resin (A), and therefore tend to be easily exposed on the surface of the molded product. As described above, the hydrophilic copolymer (B) and the fatty acid metal salt (C) can be blended with the resin (A) because the melt viscosities at the time of molding are different from those of the resin (A).

On the other hand, for example, a resin raw material having a high melting point (for example, about 320 ° C. or higher) and an extremely high polarity is difficult to disperse, so that it is difficult to obtain a desired dust suppressing effect. That is, since the hydrophilic copolymer (B) and the fatty acid metal salt (C) are more likely to gather near the surface layer of the molded product than the above resin (A), the dust suppressing effect is more likely to be exhibited.

On the contrary, if the resin raw material has a high melting point of about 320 ° C. or higher and an extremely high polarity, it is difficult to disperse the resin raw material, so that it is difficult to obtain the desired dust suppressing effect.

That is, since the hydrophilic copolymer (B) and the fatty acid metal salt (C) are more likely to gather near the surface layer than the inside of the molded product than the above resin (A), the dust suppressing effect is likely to be exhibited.

Further, the polar group of the low molecular weight fatty acid metal salt (C) and the hydrophilic copolymer (B) having a polyoxyethylene chain have an affinity. Therefore, when the hydrophilic copolymer (B) adheres to the fatty acid metal salt (C), the hydrophilic copolymer (B) and the fatty acid metal salt (C) are prevented from being desorbed, and a large amount is present near the surface layer of the molded product. Can exist in. Therefore, the adhesion suppressing effect is likely to be exhibited against both hydrophilic and hydrophobic dust stains.

Embodiment 2.
The molded product according to the present embodiment comprises the above-mentioned thermoplastic resin composition. The molded product according to the present embodiment has the effect of suppressing the adhesion of both hydrophilic dust stains and hydrophobic dust stains by being composed of the above-mentioned thermoplastic resin composition.

In the molded product according to the present embodiment, the concentration of the fatty acid metal salt (C) (content in the thermoplastic resin composition) near the surface of the molded product (the portion from the surface to a certain depth) is the molded product. It is preferable that the concentration is higher than the concentration of the fatty acid metal salt (C) in the inside (a portion deeper than a certain depth from the surface). Specifically, for example, the concentration of the fatty acid metal salt (C) in the portion within 10 nm from the surface of the molded product may be higher than the concentration of the fatty acid metal salt (C) in the portion deeper than 10 nm from the surface of the molded product. preferable.

Such a difference in the concentration of the fatty acid metal salt (C) in the depth direction of the molded product is, for example, in the molded product in a state where the surface of the molded product is scraped with Ar ions to each depth. It can be confirmed by performing elemental analysis of the metal element M (measurement of the area ratio of the metal element M) on the surface using X-ray photoelectron spectroscopy (XPS) (see FIG. 2).

For example, as shown in FIG. 1, the concentration of the fatty acid metal salt (C) (area ratio of the metal element M) at each depth is measured for a portion within 10 nm from the surface of the molded product (measurement depth A). Then, find the highest concentration among them. On the other hand, the concentration of the fatty acid metal salt (C) is measured at a depth (L / 2: measurement depth B) of half the thickness L of the molded product shown by the dotted line in FIG. By comparing the measured values of these concentrations, it is possible to confirm the difference in the concentration of the fatty acid metal salt (C) in the depth direction of the molded product.

For example, in a sample (test piece) of a molded product having an antifouling effect on both sexes, which will be described later in the examples, the concentration of the fatty acid metal salt (C) within 10 nm from the surface is 10 nm from the surface of the molded product. It was more than twice the concentration of the fatty acid metal salt (C) in the deep part. In a specific example, the concentration of the fatty acid metal salt (C) in the portion within 10 nm from the surface is a maximum of 3.2% by mass, and the concentration of the fatty acid metal salt (C) in the portion deeper than 10 nm from the surface of the molded product. The concentration was about 0.3% by mass to 0.6% by mass, and the former was about 5 to 10 times the latter.

In the fatty acid metal salt (C), the R portion is a non-polar group and the remaining portion is a polar group. During molding, it is considered that the fatty acid metal salt (C) is aligned with the polar group attached to the mold and the non-polar group directed toward the inside of the thermoplastic resin composition. Further, after molding, other fatty acid metal salts (C) melted inside the thermoplastic resin composition are transferred to the surface.

Further, since the fatty acid metal salt (C) has low compatibility with the resin, if it is blended in an amount equal to or higher than the critical solubility (concentration), it is diffused on the surface of the thermoplastic resin composition (molded article). In the vicinity of the surface of the thermoplastic resin composition, a plurality of fatty acid metal salts (C) are bonded to each other with their polar groups, and the hydrophobic groups R, which are non-polar groups, are arranged on the outside (air side) of the molded product. Conceivable.

Therefore, in the vicinity of the surface of the molded product, the concentration of the fatty acid metal salt (C) in the thermoplastic resin composition is higher than that inside the molded product, and the surface of the molded product to which dust stains adhere is efficiently surfaced. It is possible to reduce energy and obtain water and oil repellent effects. As a result, unlike the case where the fatty acid metal salt (C) is used as a lubricant, a mold release agent, etc., which are generally used, a new effect of suppressing the adhesion of hydrophobic dust stains on the surface of the molded product is obtained. can get.

Embodiment 3.
The product of the present embodiment includes the above-mentioned molded product. That is, the above-mentioned molded product is used, for example, as a resin part (internal part, housing, etc.) of a product such as a home electric appliance or an OA device. By providing the above-mentioned molded product, the product of the present embodiment has the effect of improving cleanliness and reducing the frequency of maintenance.

Products include, for example, personal computers, laptop computers, CRT displays, printers, mobile terminals, mobile phones, copiers, fax machines, recording medium (CD, CD-ROM, DVD, PD, FDD, etc.) drives, parabolic antennas, electric tools. , VTR, TV, iron, hair dryer, rice cooker, microwave oven, audio equipment, audio equipment (audio, laser disc (registered trademark), compact disc, etc.), lighting equipment (LED), remote control, ventilation fan, range hood, refrigerator , Air conditioners (air conditioners, dehumidifiers, humidifiers, etc.), air purifiers, vacuum cleaners, rice cookers, cooking heaters, bath products, toilet products, jet towels, electric fans, typewriters, word processors, automobiles, vehicles Equipment (car navigation, car stereo, etc.), miscellaneous goods, etc. can be mentioned.

Further, for example, if the above molded products are applied to resin parts such as air conditioners, doors, display devices, insulators, mirrors, measuring instruments, and operation parts of various devices, the adhesion of dust stains is reduced and cleanliness is reduced. Can be improved and maintenance frequency can be reduced. In particular, the above-mentioned molded product is useful as a resin part of a product that cannot be maintained by a user or a trader for a long period of time.

The molded product made of the above-mentioned thermoplastic resin composition of the present embodiment can be applied as long as the product is provided with resin parts, and can be widely applied not only to the above-mentioned applications.

Further, since the antifouling effect can be easily obtained only by molding, there is an advantage that complicated processes such as moving and applying the molded product are overwhelmingly less than those of painting or coating having an antifouling effect. Therefore, the molded product made of the above-mentioned thermoplastic resin composition is suitable for mass production of products and has extremely high practicality. Further, the molded product made of the above-mentioned thermoplastic resin composition is applied as an exterior member without worrying about uneven coating, rainbow pattern, glossiness, etc. on the surface as compared with coatings and coatings having an antifouling effect. Due to its easy advantage, it is suitable for mass production of products and is extremely practical.

FIG. 5 is a schematic cross-sectional view of the air conditioner according to the present embodiment. As shown in FIG. 5, the main body case 10 of the indoor unit of the air conditioner is formed in a horizontally long substantially rectangular parallelepiped shape, an air suction port 11 is provided on the upper surface thereof, and an air outlet 12 is provided on the lower surface thereof. Is provided. A pre-filter 17 is provided from the downstream side of the air suction port 11 to the front side of the main body case 10. Further, a front panel 14 that covers the front surface of the main body case 10 is provided.

Inside the main body case 10, a fan 13 for sucking indoor air sucked from the air suction port 11 into the room from the air outlet 12 is provided. A heat exchanger 22 is arranged on the upstream side of the fan 13, and an air passage 21 is provided on the downstream side of the fan 13, and air passes through the air passage 21. A drain pan 18 is provided under the heat exchanger 22.

Although not shown, a fan motor for driving the fan 13, a control unit for controlling the operation of the air conditioner, and the like are provided in the main body case 10.

The vertical wind direction plates 15 and 16 adjust the vertical blowing angle of the air blown from the air outlet 12. The left and right wind direction plates 19 adjust the blowing angle of the air blown from the air outlet 12 in the left-right direction. Support shafts are provided at the ends of the upper and lower wind direction plates 15 and 16, respectively, and are rotatably and detachably supported by bearings provided on the side wall of the air outlet 12, and the left and right wind direction plates 19 are fixed. In some cases, the direction can be set manually, and in other cases, it can be driven by a motor to automatically rotate in the left-right direction.

When the fan 13 is driven, indoor air is sucked from the air suction port 11, and the pre-filter 17, heat exchanger 22, fan 13, air passage 21, air outlet 12, left and right air direction plates 19, vertical air direction plates 15, 16 The wind blows into the room as it passes through in order. Since hydrophilic dust stains such as dust, dust, and fibers, and hydrophobic dust stains such as oil smoke, soot, sebum, and tobacco come into contact with various air conditioner members together with the air, the air suction port 11, The pre-filter 17, heat exchanger 22, fan 13, air passage 21, air outlet 12, left and right wind direction plates 19, and vertical air direction plates 15 and 16 are constantly soiled. Further, since the sucked air also contacts the back wall 20 facing the pre-filter 17 of the front panel 14, the back wall 20 also continues to be polluted.

A styrene resin such as PS or ABS may be used as a constituent material of the front panel 14, the air outlet 12, the left and right wind direction plates 19, the vertical wind direction plates 15, 16, the air passage 21, and the back wall 20. There are many. An olefin resin such as polypropylene (PP) is often used as a constituent material for the frame of the prefilter 17. As a constituent material of the fan 13, an olefin resin such as PP or a styrene resin such as AS is often used.

A molded product made of the above-mentioned thermoplastic resin composition can be preferably used for a product such as an air conditioner that is constantly contaminated.

As an effect when the molded product made of the above-mentioned thermoplastic resin composition is applied to the air conditioner, it is possible to reduce the dirt on the members, so that improvement in cleanliness and reduction in maintenance frequency can be expected. Further, since the dirt is not re-scattered, the discomfort caused when the odor caused by the dirt reaches with the wind is reduced. In addition, it is possible to suppress the generation of mold that nourishes the attached dirt. In addition, products installed at a high position on the ceiling, such as air conditioners, need to be cleaned by the user using a stepladder or the like, which makes cleaning difficult. However, due to the application of the above molded products, the frequency of cleaning is high. Can be lowered, which is particularly preferable for elderly people.

In addition, if dirt accumulates in the gaps of the fan 13 and fills the gaps, or if dirt accumulates on the surfaces of various air passages and the air passage is narrowed, the cooling and heating capacity decreases due to the decrease in air volume. However, there is a problem that the power consumption of the fan increases, but by suppressing the dirt by applying the above-mentioned molded product, the air volume at the initial stage of purchase can be maintained and the increase in power consumption can be suppressed.

In addition, for example, styrene-based resins such as ABS and PS or olefin-based resins such as PP are often used for vegetable trays in refrigerators. For the dust box of a vacuum cleaner, a styrene resin such as ABS or PS or an olefin resin such as PP is often used. Olefin resins such as PP are often used for sirocco fans of various ventilation fans and fans of electric fans. By reducing dirt in both cases, maintenance work can be reduced.

<Evaluation method>
(1) Charpy impact strength The notched Charpy impact strength was measured according to ISO 179.

(2) Tensile strength The tensile strength (tensile yield strength) was measured according to ISO 527-1 and ISO 527-1. The measured values were compared with the tensile strength of the styrene resin (component A) alone, and the evaluation was made based on the following criteria.

[Evaluation criteria for tensile strength]
A: Retention rate is 95% or more, B: Retention rate is less than 95%, 90% or more, C: Retention rate is less than 90%, 85% or more, D: Less than 85%

(3) Surface impact strength A square plate of 150 mm × 150 mm × 2 mm (thickness) is molded using an injection molding machine, a high-speed surface impact test is performed at N = 5, and the surface impact strength (destructive energy) is measured. , The average value of N = 5 was calculated. In addition, the fracture form was evaluated based on the following criteria.

[Evaluation criteria for fracture form]
A: Longitudinal fracture, B: Mixing of ductile fracture and brittle fracture (progressive fracture number> brittle fracture number), C: Mixing of ductile fracture and brittle fracture (brittle fracture number) > Permanent fracture number), D: Brittle fracture

In the evaluation of the fracture form, the test piece does not crack and scatter after the impact test, and the striking core penetrating portion shows a form in which the striking core penetrates uniformly and remains. A brittle fracture was defined as a fracture in which the test piece broke due to its shape, etc., and the end face of the penetration portion was sharp while the strike core penetration portion was flat. As for the fracture form, a ductile fracture form is preferable to a brittle fracture form.

A high-speed surface impact tester Hydroshot HTM-1 (manufactured by Shimadzu Corporation) was used as the testing machine. As the test conditions, the collision speed of the striking core was 7 m / sec, a striking core having a semicircular tip and a radius of 6.35 mm was used, and the pedestal hole diameter was 25.4 mm.

(4) Flexural modulus The flexural modulus was measured according to ISO 178 (test piece dimensions: length 80 mm × width 10 mm × thickness 4 mm). The measured flexural modulus was evaluated based on the following criteria. It is preferable that the flexural modulus is high.

[Evaluation criteria for flexural modulus]
A: 1900 MPa% or more, B: less than 1900 MPa%, 1800 MPa% or more, C: less than 1800 MPa%, 1700 MPa% or more, D: less than 1700 MPa%

(5) Deflection temperature under load The deflection temperature under load was measured according to ISO 75-1 and 75-2. The measured load was 1.80 MPa.

(6) Evaluation of Dust Adhesion A 150 mm × 150 mm × 2 mm (thickness) square plate is prepared and left in an environment of 23 ° C. and 50% humidity for one week, and then a dust adhesion test is carried out on the square plate. did. Kanto loam (11 types of JIS test powder) was used for the evaluation of hydrophilic dust adhesion, and carbon black (12 types of JIS test powder) was used for the evaluation of hydrophobic dust adhesion.
To evaluate the adhesion of dust, after spraying a certain amount (5 g) of dust on the surface of the molded product with air, the surface of the molded product is observed at 100 times with a KEYENCE digital microscope VHX-5000, and dust adhered by image processing. The area ratio was calculated and evaluated based on the following criteria.

[Evaluation criteria for dust adhesion]
A: Dust adhesion area ratio is less than 3%, B: Dust adhesion area ratio is less than 3 to 6%, C: Dust adhesion area ratio is less than 6 to 8%, D: Dust adhesion area ratio is 8% or more

(7) Humor A molded product continuously molded by an injection molding machine at a cylinder temperature of 240 ° C., a mold temperature of 50 ° C., and an injection speed of 20 mm / s, and molding after the resin is retained in the cylinder for 10 minutes under the same conditions. The hue change (ΔE) of the product was measured. For the measurement, "Spectro Photo Meter TC-1800MKII" manufactured by Tokyo Denshoku Co., Ltd. was used. The smaller the value of the hue change (ΔE), the better the thermal stability.

[Evaluation of thermal stability]
A: Hue change (ΔE) is less than 1, B: Hue change (ΔE) is 1 or more and less than 2, C: Hue change (ΔE) is 2 or more and less than 3, D: Hue change (ΔE) is 3 or more.

<Examples 1 to 60, Comparative Examples 1 to 62>
100 parts by mass of A to D components (total amount of A to D components) shown in Tables 1 to 6, 0.3 parts by mass of mold release agent [Rikken Vitamin Co., Ltd .: Riquester EW400 (product name)], phosphorus-based heat Stabilizer [IRGAFOS168 (product name) manufactured by BASF] 0.1 part by mass, phenol-based heat stabilizer [BASF; IRGANOX1076 (product name)] 0.1 part by mass, hindered amine-based light stabilizer [ADEKA ADEKA Co., Ltd. LA-57 (product name)] 0.2 parts by mass and bendtriazole-based ultraviolet absorber [SEESORB701 (product name) manufactured by Cipro Chemical Co., Ltd.] 0.1 parts by mass are mixed with a V-type blender to mix the mixture. Obtained.

The obtained mixture was supplied from the first supply port of the extruder. The supply amount of the raw material (mixture) was precisely measured by a measuring instrument [CWF manufactured by Kubota Co., Ltd.]. A vent type twin-screw extruder with a diameter of 30 mm (TEX30α-38.5BW-3V, Japan Steel Works, Ltd.) is used to extrude the raw material, the screw rotation speed is 200 rpm, the discharge rate is 20 kg / h, and the vent vacuum The raw materials were melt-kneaded under the condition of 3 kPa to obtain pellets of the thermoplastic resin composition. Regarding the extrusion temperature, the temperature from the first supply port to the die portion was set to 220 ° C.

A part of the obtained pellets is dried by a hot air circulation type dryer at 80 ° C. for 4 hours, and then a test piece for evaluation (Examples 1 to 60) using an injection molding machine (FANUC Co., Ltd. T-150D). And as Comparative Examples 1 to 62). The basic conditions for injection molding were a cylinder temperature of 200 ° C., a mold temperature of 50 ° C., and an injection speed of 20 mm / s.

The components A to D (each component of the symbol notation) shown in Tables 1 to 6 are as follows.

[Component A]
(HIPS)
High impact polystyrene resin [manufactured by PS Japan Corporation, H8762 (product name), rubber content: 9% by mass]
(PS)
Polystyrene resin [manufactured by PS Japan Corporation, H77 (product name)]
(ABS)
ABS resin [Made by Japan A & L Co., Ltd., Clarastic SXH-330 (trade name), mass average molecular weight converted to standard polystyrene by GPC: 90,000, butadiene rubber component about 17.5 mass%, mass average rubber particle diameter Is 0.40 μm]

[B component]
(PEPO-1)
Copolymer having a structure bonded alternately repeating a block of a polyolefin and a block of a hydrophilic polymer [manufactured by Sanyo Chemical Industries, Bae Rekutoron HS (trade name), a surface resistance value = 4 × 10 ⁵ Ω]
(PEPO-2)
Polyetheresteramide [manufactured by Sanyo Chemical Industries, Pelestat NC6321 (trade name), a surface resistivity = 1 × 10 ⁹ Ω]

[C component]
(StZn)
Zinc stearate [manufactured by NOF CORPORATION, zinc stearate (product name), metal content = 10.5-11.3%, free fatty acid = 0.5% or less]
(StAl-1)
Aluminum monostearic acid (dihydroxy) [manufactured by NOF CORPORATION, aluminum stearate 300 (product name), metal content = 10.0 to 11.5%, free fatty acid = 8.0% or less]
(StAl-2)
Aluminum distearate (hydroxy) [manufactured by NOF CORPORATION, aluminum stearate 600 (product name), metal content = 8.5-10.0%, free fatty acid = 12.0% or less]
(StAl-3)
Aluminum monostearate [manufactured by NOF CORPORATION, aluminum stearate 900 (product name), metal content = 6.5-8.0%, free fatty acid = 20-30%]

[D component]
(MH-SEBS)
Maleic acid-modified styrene-ethylene / butylene-styrene block copolymer obtained by graft modification with maleic anhydride (acid anhydride of unsaturated dicarboxylic acid) [Kraton Polymer Co., Ltd., FG1901GT (product name), rubber component content = 70 wt%]
(AC-SBS)
Acrylic acid-modified styrene-butadiene-styrene block copolymer obtained by graft modification with acrylic acid (acid anhydride of unsaturated monocarboxylic acid) ["Toughprene A" (product name) manufactured by Asahi Kasei Chemicals Co., Ltd. is used as xylene. The mixture was heated and stirred at 130 ° C. under a nitrogen stream. Acrylic acid and di-2-ethylhexyl peroxydicarbonate were added dropwise thereto, and then stirring was continued to proceed with the reaction. Then, the content was lowered to room temperature, charged into acetone, and filtered to obtain an acrylic acid-modified styrene-butadiene-styrene block copolymer. The amount of acrylic acid added was 2% by mass. ]
(SBS)
Styrene-butadiene-styrene block copolymer [manufactured by Asahi Kasei Chemikels Co., Ltd., Toughprene A (product name), rubber component content = 60 wt%]

The evaluation results of (1) to (6) above for the obtained test pieces for evaluation (Examples 1 to 60 and Comparative Examples 1 to 62) are shown in Tables 1 to 6.

From the evaluation results shown in Tables 1 to 6, the thermoplastic containing the styrene resin (A), the hydrophilic copolymer (B), the fatty acid metal salt (C), and the styrene thermoplastic elastomer (D). In the example of the molded product made of the resin composition, it can be confirmed that an excellent adhesion suppressing effect (antifouling effect) can be obtained against hydrophilic and hydrophobic dust stains. Further, in the examples, it can be confirmed that an excellent antifouling effect can be obtained without lowering the mechanical strength such as the impact strength.

Further, when the styrene-based thermoplastic elastomer (D) contains a styrene-based thermoplastic elastomer graft-modified with an unsaturated carboxylic acid or a derivative thereof, the values of Charpy impact strength and surface impact strength (fracture energy) are improved. As a result, the fracture form in the high-speed surface impact test becomes good.

Further, as compared with the case where the styrene-based thermoplastic elastomer (D) is "AC-SBS" (when unsaturated monocarboxylic acid or its acid anhydride is used for graft modification), the styrene-based thermoplastic elastomer (D) When is MH-SEBS (when unsaturated dicarboxylic acid or its acid anhydride is used for graft modification), the values of Charpy impact strength and surface impact strength (fracture energy) are further improved, and the speed is higher. The fracture form in the surface impact test is good.

Further, the hue change (ΔE) is smaller when the styrene-based thermoplastic elastomer (D) is MH-SEBS than when it is “AC-SBS”, and the evaluation of thermal stability is better. .. Among unsaturated dicarboxylic acids or acid anhydrides thereof, maleic acid or acid anhydrides thereof is particularly preferable.

When aluminum distearate (hydroxy) is used as the fatty acid metal salt (C) (that is, when the valence of the metal element M is 3, and a metal salt containing two fatty acids is used), Compared with the case of using zinc stearate, aluminum monostearate or aluminum tristearate, there is a tendency that the adhesion suppressing effect (antifouling effect) on both hydrophilic dust stains and hydrophobic dust stains is superior. ..

The embodiments and examples disclosed this time should be considered to be exemplary and not restrictive in all respects. The scope of the present invention is shown by the scope of claims rather than the above description, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

10 Main body case, 11 Air inlet, 12 Air outlet, 13 Fan, 14 Front panel, 15, 16 Vertical air direction plate, 17 Pre-filter, 18 Drain pan, 19 Left and right air direction plate, 20 Back wall, 21 Air passage, 22 Heat Exchanger.

Claims (11)

Styrene resin (A) and
Hydrophilic copolymer (B) having a polyoxyethylene chain and
The fatty acid metal salt (C) represented by the following formula (1) and
A thermoplastic resin composition containing a styrene-based thermoplastic elastomer (D).

M (OH) y (R-COO) x ... (1)

(In formula (1), R is an alkyl group or an alkenyl group having 6 to 40 carbon atoms. M is at least one metal selected from the group consisting of aluminum, zinc, calcium, magnesium, lithium and barium. It is an element. X and y are independent integers of 0 or more, and satisfy the relationship of x + y = [valence of M].) 100 parts by mass of the styrene resin (A), 1 to 20 parts by mass of the hydrophilic copolymer (B), 0.5 to 10 parts by mass of the fatty acid metal salt (C), and the styrene thermoplastic elastomer (D). The thermoplastic resin composition according to claim 1, which comprises 0.5 to 20 parts by mass. The thermoplastic resin composition according to claim 1 or 2, wherein the styrene-based thermoplastic elastomer (D) contains a styrene-based thermoplastic elastomer graft-modified with an unsaturated carboxylic acid or a derivative thereof. The thermoplastic resin composition according to claim 3, wherein the unsaturated carboxylic acid or a derivative thereof is an unsaturated dicarboxylic acid or an acid anhydride thereof. The thermoplastic resin composition according to claim 4, wherein the unsaturated dicarboxylic acid or an acid anhydride thereof is maleic acid or an acid anhydride thereof. The thermoplastic resin composition according to claim 5, wherein the maleic acid or an acid anhydride thereof is maleic anhydride. The thermoplastic resin composition according to any one of claims 1 to 6, wherein the styrene resin (A) is at least one selected from the group consisting of polystyrene resin and impact-resistant polystyrene resin. The thermoplastic resin composition according to any one of claims 1 to 7, wherein in the formula (1), M is at least one metal element selected from aluminum and zinc. The invention according to any one of claims 1 to 8, wherein the hydrophilic copolymer (B) is a hydrophilic copolymer (B1) in which a polyolefin and a hydrophilic polymer having a polyoxyethylene chain are repeatedly and alternately bonded. Thermoplastic resin composition. A molded product comprising the thermoplastic resin composition according to any one of claims 1 to 9. A product comprising the molded product according to claim 10.

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