JP7196492B2 - Resin composition and molded article thereof - Google Patents

Description

The present invention relates to a resin composition, more specifically, a resin composition containing polyester and polysiloxane, and the molded article thereof has improved dust resistance and washability against sebum stains, as well as high impact resistance. It relates to a resin composition that imparts and a molded article thereof.

Polyester is widely used in various fields such as OA (office automation) equipment, information and communication equipment, electrical and electronic equipment, automobiles, and construction due to its excellent heat resistance, mechanical properties, and electrical properties. . Polyester has a high surface specific resistance, and the static electricity induced by contact or friction causes dust to adhere to the surface of the molded product. For this reason, electronic devices such as ATMs and POS terminals, which are touched by an unspecified number of people, are required to be resistant to adhesion of dust and washable to remove sebum stains. In order to meet these demands, it is desired to impart antistatic properties and detergency to remove sebum stains and the like while maintaining the mechanical properties inherent in polyester. In other words, there is a demand for a resin composition that gives molded articles that have good antistatic properties and washability, as well as excellent impact resistance.

In order to modify the polyester, it is known to mix a polysiloxane compound with the polyester to obtain a polysiloxane-modified polyester. For example, a linear polyester resin is reacted with a specific polysiloxane compound to impart wear resistance to polysiloxane-modified polyester (Patent Document 1), and a polysiloxane structure is introduced into the main chain to reduce the strength of the molded product. polyester resin composition (Patent Documents 2 and 3), etc., a silicon-modified polyester containing a segment composed of polyester units and a segment of reactive group-containing organopolysiloxane and having excellent moldability (Patent Document 4), polylactic acid and a polylactic acid-based resin composition containing a base resin and an organic polysiloxane and having impact resistance and the like (Patent Documents 5 to 7).

On the other hand, as a method for preventing adhesion of stains to polyester molded articles, a method is known in which an ionic surfactant such as an alkali metal sulfonate or a phosphonium sulfonate is blended to prevent electrification. The antistatic performance of such an ionic surfactant is exhibited when a part of the surfactant is deposited on the surface from a molded article of a resin composition containing the surfactant. However, in a molded article of a resin composition in which a compound with low surface tension such as a polysiloxane compound is added to polyester, the polysiloxane compound precipitates on the surfactant deposited on the surface of the molded article, so the antistatic performance is poor. drops markedly. A molded article obtained from a resin composition containing a polyester having a polysiloxane structure is required to suppress bleed-out, have impact resistance, have an antistatic function, and further have dust resistance and washability. .

By the way, in order to produce a polysiloxane-modified polyester, generally, (1) a method of directly kneading a polysiloxane compound and a polyester, or (2) when obtaining a polyester by a polycondensation reaction, a reactive functional group A method of producing a polysiloxane-modified polyester by adding a polysiloxane compound having as one of the reaction components to the reaction system and chemically bonding the polysiloxane compound to the resulting polyester.

However, although the method (1) is a simple method, the resulting polysiloxane-modified polyester may simply be a blend of the polyester and the polysiloxane compound, or the polysiloxane compound and the polyester may react. , only a very small portion of the polyester compound is chemically reacted, and a large amount of unreacted polysiloxane compound is mixed. Therefore, when the obtained polysiloxane-modified polyester is used as a molded product, there is a problem that the polysiloxane compound bleeds out onto the surface of the molded product, causing a phenomenon called bleed-out. Furthermore, as described above, deposition of the surfactant on the surface of the molded article is hindered, resulting in a significant reduction in antistatic performance. The method (2) also has a problem in the reactivity of the polysiloxane compound in the polycondensation of the polyester, and it is difficult to obtain the desired polysiloxane-modified polyester. Therefore, if the proportion of the polysiloxane compound used relative to the monomers forming the polyester is increased in an attempt to obtain a polysiloxane-modified polyester having the desired modification effect, the degree of polymerization of the obtained polyester is lowered, and as a result, , there is also the problem that the properties of the polyester are impaired.

The present inventors have developed a polysiloxane-modified polylactic acid-based composition (Patent Documents 8 and 9) and a polycarbonate resin composition (Patent Document 10) has already been disclosed. However, with these resin compositions, it has not been possible to obtain a resin molded article having antistatic properties, dust resistance, and washability.

JP-A-09-316185 JP-A-10-95902 JP-A-10-100168 JP-A-03-205426 JP-A-11-116786 Japanese Patent Application Laid-Open No. 2004-352908 Japanese Patent Application Laid-Open No. 2007-262200 Japanese Patent No. 5573833 JP 2012-072351 A JP-A-2004-035726

An object of the present invention is to provide a resin composition that suppresses the adhesion of dust, that is, has dust resistance, has the ability to wash off adhered sebum, and can improve impact resistance in molded articles of resins containing polyester. It is to provide the molded product.

The present inventors have made intensive studies to improve the impact resistance, dust resistance, washability, flame retardancy, etc. of polyester. As a result, for a siloxane compound having a specific structure, the molecular weight and molecular structure are selected, and optionally, a specific sulfonate is melt-kneaded into the polyester to suppress bleed out and improve antistatic performance. The present inventors have found that a molded article having excellent dust resistance and washability against sebum and remarkably improved impact resistance can be obtained by providing it, and have completed the present invention.

That is, the present invention blends a polyester and a polysiloxane compound represented by the formula (1) in the range of 0.1% by mass or more and 6% by mass or less with respect to the polyester, and the formula (1) The represented polysiloxane compound relates to a resin composition having a number average molecular weight of 900 or more and 120,000 or less.

(wherein R ₃ , R ₄ , R ₅ , R ₆ and R ₇ are alkyl groups, alkenyl groups, aryl groups, aralkyl groups, alkylaryl groups having 18 or less carbon atoms, or -(CH ₂ ) _α -NH-C ₆ H ₅ (α is an integer of 1 to 8), which may be the same or different, may be wholly or partially substituted with halogen atoms, and R ₈ and R ₉ are divalent organic groups; and m and p represent numerical values of m≧0 and p>0, respectively.)

The present invention also relates to a molded article molded from the above resin composition.

According to the resin composition of the present invention, the polyester acts on the polysiloxane compound represented by the highly polar formula (1), and the polyester and the polysiloxane compound efficiently interact through chemical bonds or hydrogen bonds. Therefore, the resin composition can be advantageously obtained. Therefore, in the molded article of the resin composition of the present invention, the deposition of the polysiloxane compound on the surface of the molded article is suppressed. Without impairing mechanical properties such as impact resistance, it has various excellent properties provided by the polysiloxane structure, and has excellent antifouling properties and detergency against sebum.

The resin composition of the present embodiment comprises a polyester and a polysiloxane compound represented by the formula (1) in a range of 0.1% by mass or more and 6% by mass or less with respect to the polyester, and the formula ( The polysiloxane compound represented by 1) is a resin composition having a number average molecular weight of 900 or more and 120,000 or less.

(wherein R ₃ , R ₄ , R ₅ , R ₆ and R ₇ are alkyl groups, alkenyl groups, aryl groups, aralkyl groups, alkylaryl groups having 18 or less carbon atoms, or -(CH ₂ ) _α -NH-C ₆ H ₅ (α is an integer of 1 to 8), which may be the same or different, may be wholly or partially substituted with halogen atoms, and R ₈ and R ₉ are divalent organic groups; and m and p represent numerical values of m≧0 and p>0, respectively.)

The resin composition of the present embodiment further contains a sulfonate represented by formula (2) in a range of 0.01% by mass or more and 6% by mass or less with respect to the polyester. good.
R ₁₀ -SO ₃ M ⁺ (2)
(In the formula, R ₁₀ represents an alkyl group having 1 to 40 carbon atoms, an aralkyl group having 6 to 40 carbon atoms, or an aryl group having 6 to 40 carbon atoms, and M ⁺ represents a metal ion or an organic onium ion.)

Usual thermoplastic polyesters are used as the polyester, and there is no particular limitation. For example, polyalkylene terephthalates such as polyethylene terephthalate, polybutylene terephthalate, and polycyclohexanedimethylene terephthalate; polyalkylene naphthalates such as polyethylene naphthalate and polybutylene naphthalate; aromatic polyesters such as polycarbonate; polyester constituents and other acids components and/or glycol components (e.g. acid components such as isophthalic acid, adipic acid, sebacic acid, glutaric acid, diphenylmethanedicarboxylic acid, dimer acid, glycols such as hexamethylene glycol, bisphenol A, neopentyl glycol alkylene oxide adducts). Polyether ester resin copolymerized with component); degradable polyhydroxybutyrate, polycaprolactone, polybutylene succinate, polyethylene succinate, polylactic acid, polymalic acid, polyglycolic acid, polydioxanone, poly(2-oxetanone), etc. A wide range of polyesters such as aliphatic polyesters, aromatic polyester/polyether block copolymers, aromatic polyester/polylactone block copolymers, and polyarylates can be mentioned. Among these, at least one selected from the group consisting of polylactic acid, polycarbonate, polyethylene terephthalate, polybutylene terephthalate and polyethylene naphthalate is preferred.

In addition, such a thermoplastic polyester is a single or a blend of multiple resins (for example, a blend of polylactic acid and polycarbonate), or a copolymer thereof (for example, a copolymer of polybutylene terephthalate and polytetramethylene glycol). may be In particular, those having a melting point of 170° C. to 300° C. are preferable because they exhibit heat resistance properties. These may be used alone or in combination of two or more, but those not substituted with halogen atoms are preferred from the standpoint of preventing emissions of halogen-containing gases, which may be a concern during combustion, into the environment.

The number average molecular weight of the polyester is preferably 15,000 or more and 1,000,000 or less, more preferably 15,000 or more and 200,000 or less, and still more preferably 15,000 or more and 100,000 or less. A polyester having such an average molecular weight can be adjusted in molecular weight by using a molecular weight modifier, a catalyst, etc. as necessary during production. A polyester having such a molecular weight has excellent mechanical properties such as impact resistance.

In addition, when the following thermoplastic polyester is used as the polyester, the surface resistivity is low and the antistatic function is excellent. Sufficient dust resistance is obtained even without the combined use of the sulfonate represented by formula (2). Therefore, by melt-kneading the thermoplastic polyester with the polysiloxane compound represented by the formula (1), a resin composition having excellent antifouling properties can be obtained. Such thermoplastic polyesters include at least one dicarboxylic acid monomer selected from the group consisting of dicarboxylic acid derivatives such as terephthalic acid (TPA), isophthalic acid (IPA), and dimethyl terephthalate (DMT). at least one selected from ethylene glycol, diethylene glycol (DEG), cyclohexanedimethanol (CHDM) and 2,2,4,4-tetramethyl-1,3-cyclobutanediol (TMCD) as a dicarboxylic acid and a diol monomer; At least one diol and a thermoplastic polyester obtained from raw materials can be mentioned.

The polysiloxane compound represented by formula (1) has a side chain containing a diamino group in at least part of the side chain of the polysiloxane structure. Here, the side chain containing a diamino group is one containing an amino group (--NH ₂ ) at the end of the side chain and an imino group (--NH--) in the main chain of the side chain.

In formula (1), R ₃ , R ₄ , R ₅ , R ₆ and R ₇ are alkyl groups, alkenyl groups, aryl groups, aralkyl groups, alkylaryl groups or —(CH ₂ ) _α — having 18 or less carbon atoms. NH—C ₆ H ₅ (α is an integer of 1 to 8), which may be the same or different, and may be wholly or partially substituted with halogen atoms such as fluorine and chlorine atoms. Alkyl groups, alkenyl groups, aryl groups, aralkyl groups and alkylaryl groups may have 18 or less carbon atoms. In —(CH ₂ ) _α —NH—C ₆ H ₅ , α may be an integer of 1-8. Among these, R ₃ , R ₄ , R ₅ , R ₆ and R ₇ are preferably methyl groups or phenyl groups.

R ₈ and R ₉ may be any divalent organic group that constitutes a side chain containing a diamino group of the polysiloxane compound represented by formula (1), and specific examples thereof include an alkenyl group and the like. can.

p represents a numerical value of p>0, and is appropriately selected in relation to the diamino group. m represents a numerical value of m≧0. p and m are appropriately selected in relation to the molecular weight of the polysiloxane compound.

The polysiloxane compound represented by formula (1) is blended in a range of 0.1% by mass or more and 6% by mass or less with respect to the polyester. The blending amount of the polysiloxane compound is preferably 0.5% by mass or more and 6% by mass or less, more preferably 1% by mass or more and 5.5% by mass or less, relative to the polyester.

The polysiloxane compound represented by formula (1) has a number average molecular weight of 900 or more and 120,000 or less. The number average molecular weight is preferably 900 or more and 30000 or less, more preferably 900 or more and 8000 or less. By having such a number-average molecular weight, the polysiloxane compound can efficiently bond to the polyester and interact with the polyester through hydrogen bonding, thereby imparting dust resistance and washability to the molded article. can. That is, in the resin composition of the present embodiment, it is preferable that the polyester and the polysiloxane compound interact with each other through chemical bonds or hydrogen bonds.

In the sulfonate represented by formula (2), R ₁₀ represents an alkyl group having 1 to 40 carbon atoms, an aralkyl group having 6 to 40 carbon atoms, or an aryl group having 6 to 40 carbon atoms. Examples of alkyl groups having 1 to 40 carbon atoms include dodecyl group, decyl group, butyl group and ethyl group, with dodecyl group and decyl group being particularly preferred. Examples of the aralkyl group having 6 to 40 carbon atoms include benzyl group and phenethyl group, with benzyl group being particularly preferred. Examples of the aryl group having 6 to 40 carbon atoms include phenyl group, naphthyl group, tolyl group, dodecylphenyl group and the like, and dodecylphenyl group is particularly preferred. Some of the hydrogen atoms in these alkyl groups, aralkyl groups and aryl groups may be substituted with halogen atoms such as fluorine atoms, and the aralkyl groups and aryl groups may contain heteroatoms. Specific examples of the sulfonic acid component include dodecylbenzenesulfonic acid and perfluoroalkanesulfonic acid.

In formula (2), examples of the metal component of the metal ion in M ⁺ include alkali metals and alkaline earth metals such as potassium, sodium, cesium, and rubidium, and examples of the onium component of the organic onium ion include phosphonium , ammonium and the like. Among these, sodium, potassium, phosphonium and ammonium are preferred, and sodium is particularly preferred. These can be used alone or in combination of two or more.

When the resin composition of the present embodiment contains a sulfonate represented by formula (2), the sulfonate is blended in the range of 0.01% by mass or more and 6% by mass or less with respect to the polyester. . The content of the sulfonate is preferably 0.1% by mass or more and 5% by mass or less, more preferably 1% by mass or more and 4% by mass or less, relative to the polyester.

In addition to the polysiloxane compound represented by the above formula (1), the resin composition of the present embodiment contains a polysiloxane compound having no diamino group and other resins within a range that does not impede the effects of the present invention. may have been Additives such as various heat stabilizers, antioxidants, colorants, fluorescent whitening agents, fillers, release agents, softeners, antistatic agents, anti-drip agents, impact modifiers, and other polymers etc. may be blended.

Examples of the heat stabilizer include metal hydrogensulfate salts such as sodium hydrogensulfate, potassium hydrogensulfate and lithium hydrogensulfate, and metal sulfates such as aluminum sulfate. These heat stabilizers are used in the range of 0% by mass or more and 0.5% by mass or less with respect to 100% by mass of polyester.

Examples of fillers include glass fibers, glass beads, glass flakes, carbon fibers, talc powder, clay powder, mica, potassium titanate whiskers, wollastonite powder, silica powder, and aluminum borate whiskers.

Examples of impact modifiers include acrylic elastomers, polycarbonate elastomers, core-shell type methyl methacrylate-butadiene-styrene copolymers, methyl methacrylate-acrylonitrile-styrene copolymers, ethylene-propylene rubbers, ethylene-propylene-diene-based Rubber and the like can be mentioned.

Anti-drip agents include, for example, fiber-forming fluoropolymers that form a fiber structure (fibril-like structure) in a resin. By blending such a fiber-forming fluoropolymer, the drip phenomenon during combustion can be suppressed. Examples of the fiber-forming fluoropolymer include tetrafluoroethylene copolymers such as polytetrafluoroethylene and tetrafluoroethylene-hexafluoropropylene copolymers.

Other polymers include, for example, polyesters such as polyethylene terephthalate and polybutylene terephthalate; polystyrene, high impact polystyrene, acrylonitrile-styrene copolymers and acrylic rubber modified products thereof, acrylonitrile-butadiene-styrene copolymers, acrylonitrile-ethylene- Styrene-based polymers such as propylene-diene-based rubber (EPDM) and styrene copolymers, polypropylene, and polymers commonly used as alloys with polyesters can be mentioned.

The method for producing the resin composition of the present embodiment includes a polyester, a polysiloxane compound represented by formula (1), and, if necessary, a sulfonate represented by formula (2) and a fiber-forming type. A method of melting a fluoropolymer and applying a shearing action to mix and stir can be used. As a method for heating the polyester to its melting temperature or higher, first, the polyester is supplied to an extruder whose cylinder temperature is set to a temperature higher than its melting temperature, for example, 250° C. or higher. After melting the polyester, the extruder is fed with predetermined amounts of the polysiloxane compound represented by formula (1) and, optionally, the sulfonate represented by formula (2). Then, the screw is rotated at a predetermined speed to apply a shearing force to the reactants to knead them to produce a resin composition. Since the polyester is in a molten state, a graft polymer in which the polysiloxane compound is efficiently bonded or a state in which the polysiloxane compound and the polyester interact through hydrogen bonding can be obtained.

The molded article of the present embodiment is not limited as long as it is obtained by molding the above resin composition, and electrical and electronic equipment such as OA (office automation) equipment, information and communication equipment, and electrical appliances. , automobile field, construction field. As the molded article, electronic devices that can be operated by an unspecified number of people, such as ATM terminals, POS terminals, multifunction copiers, servers, smart phone terminals, tablet terminals, etc., are particularly suitable. These parts have excellent mechanical strength such as impact resistance, excellent dust resistance and washability, and excellent flame retardancy.

These molded articles can be produced using, for example, an injection molding method, an injection/compression molding method, or the like.

The resin composition of the present invention will be specifically described. Materials used in Examples and Comparative Examples are as follows.

<1. Polyester>
- PLA: polylactic acid compound (manufactured by NatureWorks, trade name: INGEO3251D, melting point: 170°C, number average molecular weight: 20000)
· Copolyester: manufactured by Eastman Chemical Company, trade name: Tritan TX1501HF, number average molecular weight: 25000
<2. Sulfonate Represented by Formula (2)>
・B: Sulfonate (Sodium linear alkylbenzene sulfonate, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.)
<3. Amino Group-Containing Polysiloxane Compound Represented by Formula (1)>
C1: Side-chain diamino-type polysiloxane compound (manufactured by Dow Corning Toray Co., Ltd., trade name: FZ-3705, viscosity (25° C.): 230 mm ² /s, amino equivalent: 4000 g/mol, number average molecular weight: 8000)

The amino group-containing polysiloxane compound can be produced according to the description in Silicone Handbook (published by Nikkan Kogyo Shimbun, p.165). Specifically, an amino group-containing polysiloxane compound having an amino group in a side chain is synthesized using a siloxane oligomer obtained by hydrolysis of aminoalkylmethyldimethoxysilane, a cyclic siloxane, and a basic catalyst. Also, by using bis(aminopropyl)tetramethyldisiloxane, a cyclic siloxane and a basic catalyst, a polysiloxane compound having amino groups at both ends can be obtained. Furthermore, depending on the molecular weight of the siloxane compound component and the ratio of M units and D units constituting the siloxane compound, an appropriate amount of a partial hydrolyzed condensate of diorganodichlorosilane is dissolved in an organic solvent, and water is added to add water. A siloxane compound is decomposed and partially condensed, and then triorganomonochlorosilane is added for reaction. After completion of polymerization, the solvent is separated by distillation or the like to obtain a polysiloxane compound.

<4. Polysiloxane compound according to Comparative Example>
C2: side chain monoamino type polysiloxane compound (manufactured by Shin-Etsu Chemical Co., Ltd., trade name: KF-865, viscosity (25° C.): 110 mm ² /s, amino equivalent: 5000 g/mol, number average molecular weight: 4000)
D: Epoxy group-containing polysiloxane compound (manufactured by Dow Corning Toray Co., Ltd., trade name: SF-8411, viscosity (25° C.): 8000 mm ² /s, epoxy equivalent: 3000 g/mol)
E: Polydimethylsiloxane compound (manufactured by Shin-Etsu Chemical Co., Ltd., trade name: KF96, viscosity (25°C): 200 mm ² /s)

[Example 1]
A polylactic acid-based compound (PLA) and a side chain diamino-type polysiloxane compound (C1) are mixed with a continuous kneading extruder (manufactured by KCK Co., Ltd., trade name: KCK80X2-35VVEX (7 )), the polylactic acid-based compound (PLA) was supplied from the hopper port, and the side-chain diamino-type polysiloxane compound (C1) was supplied from the vent port. At this time, the linear alkylbenzene sulfonate sodium (B) is added to the resin composition (total amount) at a rate of 3.0% by mass, and the side chain diamino type polysiloxane compound (C1) is added to the resin composition ( total amount), and the total amount supplied per hour was 6 kg. The screw was then rotated at 32 rpm to knead these materials under melt shear and then extruded through the die mouth of the extruder into strands which were cooled in water and cut into pellets. After drying the obtained resin composition at 80° C. for 5 hours, using a 20-ton injection molding machine (trade name: EC20P-0.4A, manufactured by Toshiba Machine Co., Ltd.), cylinder temperature: 200° C., gold Mold setting temperature: molding was performed under the condition of 70°C to prepare a test piece.

The properties of the obtained test pieces were investigated by measuring the Charpy impact strength, measuring the surface resistivity and washability, and observing the state of bleeding according to the methods described below. Table 1 shows the results.

(Charpy impact strength)
The Charpy impact strength was measured according to ISO179 by notching a test piece (10 mm×80 mm×4.0 mm).

(Surface resistivity)
The surface resistivity was measured according to ASTM D257 on a test piece (70 mm x 70 mm x 2.0 mm).

(washability)
Detergency was measured using a test piece (70 mm x 70 mm x 2.0 mm) with reference to the JIS L1919C method as follows. At the center of the test piece, 30 mg of oleic acid or 10 mg of artificial sebum (the composition is shown below) colored with a red dye was applied as evenly as possible in a circle with a diameter of about 40 mm as artificial dirt. Using a towel sprayed with water, the artificial dirt on the surface of the test piece was wiped once or three times. After the wiping operation, the artificial dirt remaining on the surface of the test piece was wiped off with tissue paper attached to the surface of a disk with a diameter of 20 mm, the whiteness of the tissue paper was measured with a color difference meter, and the removal rate was calculated by the following formula.

・Composition of artificial sebum: 23% triolein, 21% paraffin wax, 6% monoolein, 10% squalene, 9% oleic acid, 9% stearic acid, 9% linoleic acid, 9% palmitic acid, 2% cholesterol, liquid 2% paraffin
・ Removal rate (%) = (A - B) / (whiteness of tissue - B) x 100
A: Whiteness of the tissue paper after wiping the artificial dirt with a towel and wiping off the artificial dirt remaining on the test piece. Whiteness of tissue paper after wiping artificial dirt on test piece

(bleed)
After heating the test piece in a hot air circulating oven at 100° C. for 100 hours, the surface of the test piece was observed with the naked eye and a microscope, and the degree of bleeding to the surface of the test piece was evaluated according to the following criteria.
○: No ooze on the surface △: Slight ooze on the surface ×: Significant ooze on the surface

[Examples 2 and 3, Comparative Examples 1 to 6]
Polylactic acid-based compound (PLA), sodium linear alkylbenzene sulfonate (B), side chain diamino polysiloxane compound (C1), side chain monoamino polysiloxane compound (C2), epoxy group-containing polysiloxane compound (D), and polydimethylsiloxane compound (E) were blended in the amounts shown in Tables 1 and 2, respectively. The results are shown in Tables 1 and 2.

From the results of Examples 1 to 3, the polylactic acid compound (PLA) was added with 3.0% by mass of linear alkylbenzene sulfonate sodium (B) and 1.0 to 5.0 of the side chain diamino type polysiloxane compound (C1). The resin composition containing % by mass has high impact strength, a surface resistivity of 10 ¹⁴ Ω or less, excellent dust resistance, and oleic acid, which is the main component of sebum, and artificial sebum by wiping with water. It was found that the removal rate was 85% or more, indicating excellent detergency.

On the other hand, from the results of Comparative Example 1, it was found that the resin composition consisting only of polylactic acid compound (PLA) had low impact strength, surface resistivity of 10 ¹⁷ Ω or more, and poor dust resistance. In addition, it was found that the removal rate of oleic acid and artificial sebum, which are the main components of sebum, by wiping with a damp cloth was 45% or more and less than 65%, indicating poor detergency. Further, from the results of Comparative Example 2, the resin composition containing only the polylactic acid-based compound (PLA) and the sodium linear alkylbenzene sulfonate (B) has a surface resistivity of 10 ¹⁴ Ω or less, which is excellent in dust resistance, and It was found that the removal rate of oleic acid and artificial sebum, which are the main components of sebum, by wiping with water was 65% or more, indicating relatively excellent detergency, but significantly inferior impact resistance. Furthermore, from the results of Comparative Example 3, the resin composition containing 3.0% by mass of sodium linear alkylbenzenesulfonate (B) and 7.0% by mass of side-chain diamino-type polysiloxane compound (C1) had impact strength. Although high, the surface resistivity was 10 ¹⁶ Ω or more, indicating poor dust resistance. In addition, it was found that the removal rate of oleic acid and artificial sebum, which are the main components of sebum, by wiping with a damp cloth was less than 65%, indicating poor detergency and bleeding.

From the results of Comparative Example 4, the resin composition containing 3.0% by mass of linear sodium alkylbenzenesulfonate (B) and 3.0% by mass of side-chain monoamino-type polysiloxane compound (C2) has excellent impact resistance. , the surface resistivity is 10 ¹⁶ Ω or more, which is poor in dust resistance, and the removal rate of oleic acid and artificial sebum, which are the main components of sebum, by wiping with water is 50 to 61%, which is poor in cleanability, and bleeding occurs. I found out. Further, from the results of Comparative Examples 5 and 6, 3.0% by mass of sodium linear alkylbenzenesulfonate (B) and 3.0% by mass of epoxy group-containing polysiloxane compound (D), or polydimethylsiloxane compound (E) A resin composition containing 3.0% by mass has excellent impact resistance, but has a surface resistivity of 10 ¹⁶ Ω or more, which is poor in dust resistance, and removes oleic acid and artificial sebum, which are the main components of sebum, by wiping with water. It was found that the washing rate was 47 to 64%, and not only was the cleaning property inferior, but bleeding occurred.

[Example 4]
Copolyester (manufactured by Eastman Chemical Co., trade name: Tritan TX1501HF) and a side chain diamino-type polysiloxane compound (C1) were mixed together in a continuous kneading extruder (manufactured by KCK Co., Ltd.) with a cylinder temperature of 270 ° C. , trade name: KCK80X2-35VVEX (7)), the copolyester was supplied from the hopper port, and the side chain diamino type polysiloxane compound (C1) was supplied from the vent port. At this time, the side chain diamino-type polysiloxane compound (C1) is supplied at a rate of 1.0% by mass with respect to the mass of the resin composition (total amount), and the total amount supplied per hour is 6 kg. did. The screw was then rotated at 32 rpm to knead these materials under melt shear and then extruded through the die mouth of the extruder into strands which were cooled in water and cut into pellets. After drying the obtained resin composition at 80° C. for 5 hours, a 20-ton injection molding machine (manufactured by Toshiba Machine Co., Ltd., trade name: EC20P-0.4A) was used to press the cylinder temperature: 280° C., gold Mold setting temperature: molding was performed under the condition of 60°C to prepare a test piece. The obtained test piece was evaluated in the same manner as in Example 1, and its properties were examined. Table 3 shows the results.

[Examples 5-7, Comparative Examples 7-8]
Copolyester (manufactured by Eastman Chemical Co., trade name: Tritan TX1501HF), sodium linear alkylbenzene sulfonate (B), and side-chain diamino-type polysiloxane compound (C1) were blended in amounts shown in Table 3, respectively. Except for that, a test piece was prepared in the same manner as in Example 4, evaluated, and its properties were investigated. Table 3 shows the results.

From the results of Examples 4, 5 and 7, the resin composition obtained by blending 1.0 to 5.0% by mass of the side chain diamino type polysiloxane compound (C1) with the copolyester (Tritan TX1501HF) has high impact strength. In addition, it has a surface resistivity of 10 ¹⁴ Ω or less, which is excellent in dust resistance, and the removal rate of oleic acid and artificial sebum, which are the main components of sebum, by wiping with water is 80% or more. rice field. Further, from the results of Example 6, the resin composition obtained by blending 3.0% by mass of linear alkylbenzene sulfonate sodium (B) and 3.0% by mass of side chain diamino-type polysiloxane compound (C1) in copolyester is , It has high impact strength, has a surface resistivity of 10 ¹⁴ Ω or less, is excellent in dust resistance, and is washable with a removal rate of 80% or more of oleic acid and artificial sebum, which are the main components of sebum, by wiping with water. was found to be superior to

On the other hand, from the results of Comparative Example 7, the resin composition consisting only of copolyester (Tritan TX1501HF) has high impact strength and excellent dust resistance with a surface resistivity of 10 ¹⁴ Ω or less. It was found that the removal rate of oleic acid and artificial sebum by wiping with water was 40% or more and less than 65%, indicating that the detergency was poor. Further, from the results of Comparative Example 8, the resin composition containing 7.0% by mass of the side-chain diamino-type polysiloxane compound (C1) has high impact strength and a surface resistivity of 10 ¹⁴ Ω or less, and is dustproof. It was found that, although it had excellent properties, the removal rate of oleic acid and artificial sebum, which are the main components of sebum, by wiping with a damp cloth was less than 50%, indicating poor detergency and bleeding.

OA (office automation) equipment, information/communication equipment, electric/electronic equipment such as electrical equipment, vehicle field, construction field, etc. Applicable to various fields, especially electronic equipment that can be operated by an unspecified number of people, such as It is suitable for parts of ATM terminals, POS terminals, multifunction copiers, servers, smartphone terminals, tablet terminals, and the like.

Claims (4)

A polyester and a polysiloxane compound represented by the formula (1) in the range of 0.1% by mass or more and 6% by mass or less with respect to the polyester are blended, and the polysiloxane compound represented by the formula (1) is a resin composition having a number average molecular weight of 900 or more and 120000 or less, wherein the polyester comprises at least one dicarboxylic acid selected from the group consisting of terephthalic acid, isophthalic acid and dimethyl terephthalate, ethylene glycol and diethylene glycol. , cyclohexanedimethanol and at least one diol selected from 2,2,4,4-tetramethyl-1,3-cyclobutanediol, and a thermoplastic polyester that is a reaction product of the resin composition.

(wherein R ₃ , R ₄ , R ₅ , R ₆ and R ₇ are alkyl groups, alkenyl groups, aryl groups, aralkyl groups, alkylaryl groups having 18 or less carbon atoms, or -(CH ₂ ) _α -NH-C ₆ H ₅ (α is an integer of 1 to 8), which may be the same or different, may be wholly or partially substituted with halogen atoms, and R ₈ and R ₉ are divalent organic groups; and m and p represent numerical values of m≧0 and p>0, respectively.) 2. The resin composition according to claim 1 , further comprising a sulfonate represented by the formula (2) in an amount of 0.01% by mass or more and 6% by mass or less based on the polyester.
R10 _{- SO3M} ⁺ (2)
(In the formula, R ₁₀ represents an alkyl group having 1 to 40 carbon atoms, an aralkyl group having 6 to 40 carbon atoms, or an aryl group having 6 to 40 carbon atoms, and M ⁺ represents a metal ion or an organic onium ion.) 3. The resin composition according to claim 1, wherein said polyester and said polysiloxane compound interact with each other through chemical bonds or hydrogen bonds. A molded article molded from the resin composition according to any one of claims 1 to 3 .