Thermoplastic resin composition and molded article thereof

Abstract

To provide a thermoplastic resin composition that enables sheet molding with superior productivity and provides a molded article exhibiting superior chemical resistance, transparency, rigidity, and heat resistance.SOLUTION: A thermoplastic resin composition comprises a vinyl copolymer (A) obtained by copolymerizing an aromatic vinyl monomer and a (meth)acrylic acid ester monomer, a rubber-reinforced graft copolymer (B) obtained by graft copolymerizing an aromatic vinyl monomer, a (meth)acrylic acid ester monomer, and a vinyl cyanide monomer in the presence of a rubbery polymer, and a polyamide elastomer (C), wherein per 100 pts.mass in total of the vinyl copolymer (A), the rubber-reinforced graft copolymer (B), and the polyamide elastomer (C), the total amount of the vinyl copolymer (A) and the rubber-reinforced graft copolymer (B) is 60 to 92 pts.mass, and the polyamide elastomer (C) is 8 to 40 pts.mass.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a thermoplastic resin composition containing a vinyl copolymer, a rubber-reinforced graft copolymer, and a polyamide elastomer. The thermoplastic resin composition of the present invention is excellent in productivity for sheet molding, and can produce molded articles that are excellent in chemical resistance, transparency, and rigidity. The present invention also relates to molded articles obtained by molding the thermoplastic resin composition. [Background technology]

[0002] Rubber-reinforced styrene-based resins, obtained by graft copolymerizing an aromatic vinyl compound such as styrene or α-methylstyrene with a vinyl cyanide compound such as acrylonitrile or methacrylonitrile onto a rubbery polymer such as a diene rubber, are excellent in mechanical strength such as impact resistance and rigidity, moldability, cost performance, etc. For this reason, rubber-reinforced styrene-based resins are widely used in applications such as home appliances, communication-related equipment, shipping containers, general merchandise, and medical-related equipment.

[0003] In such a wide range of applications, rubber-reinforced styrene resins are sometimes used as films or sheets. In this case, from the viewpoint of productivity, it is preferable for the resin to have a relatively low fluidity when molded into sheets or films (hereinafter collectively referred to as "sheet molding"). Therefore, in order to reduce fluidity, the rubber-reinforced styrene resin is designed to have a relatively high ratio of rubbery polymer.

[0004] On the other hand, although rubber-reinforced styrene resins are generally opaque, some products require transparency similar to that of polymethyl methacrylate or polycarbonate resins. To meet such requirements, it is known that transparency can be obtained even in rubber-reinforced styrene resins by adjusting the composition ratio of each component that makes up the resin, as described in Patent Document 1, for example.

[0005] Transparent sheet materials are used in conveying equipment and containers for precision parts. In these applications, the resin may be degraded by the presence of cleaning agents used in the precision parts, resulting in reduced transparency and cracks and breakage. Therefore, chemical resistance is also required to prevent such problems.

[0006] However, conventionally available transparent materials made of rubber-reinforced styrene resins have improved transparency by increasing the ratio of (meth)acrylic acid esters in their compositions, as described in, for example, Patent Documents 2 and 3. However, as a result of increasing the ratio of (meth)acrylic acid esters, chemical resistance to cleaning agents such as isopropyl alcohol has been insufficient.

[0007] Patent Document 3 proposes the following thermoplastic resin composition, which aims to improve adhesiveness to organic solvents, impact resistance, antistatic properties, and color tone, rather than sheet formability or chemical resistance. A vinyl copolymer (A) is obtained by copolymerizing a vinyl monomer mixture (a) containing at least 5 to 40 mass% of an aromatic vinyl monomer (a1), 30 to 80 mass% of a (meth)acrylic acid ester monomer (a2), and 10 to 50 mass% of a vinyl cyanide monomer (a3); a rubber-like polymer (r) is obtained by copolymerizing at least 10 to 30 mass% of an aromatic vinyl monomer (b1), 30 to 80 mass% of a (meth)acrylic acid ester monomer (b2), and 10 to 50 mass% of a vinyl cyanide monomer (b3). 3) A thermoplastic resin composition containing a graft copolymer (B) obtained by graft copolymerization of a vinyl-based monomer mixture (mb) containing 1 to 10 mass% of a vinyl-based monomer, and a polyamide elastomer (C), wherein the thermoplastic resin composition contains 40 to 90 parts by mass of the vinyl-based copolymer (A), 10 to 60 parts by mass of the graft copolymer (B), and 3 parts by mass or more of the polyamide elastomer (C) per 100 parts by mass of the total of the vinyl-based copolymer (A) and the graft copolymer (B). However, the problems of improving productivity in sheet molding and chemical resistance do not exist in Patent Document 3. Moreover, the thermoplastic resin composition of Patent Document 3 has a low molecular weight of the vinyl copolymer (A) and a low proportion of the rubber-reinforced graft copolymer (B) in the resin component, so that the sheet moldability that is the problem of the present invention cannot be obtained.

[0008] Furthermore, Patent Document 4 discloses a technique for specifying the acrylonitrile content in the acetone soluble matter of a thermoplastic resin composition. However, when this technique is used to improve chemical resistance or impart antistatic properties by blending a polyamide elastomer, there is a problem that transparency is significantly impaired. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] Japanese Patent Application Publication No. 4-180907 [Patent Document 2] Japanese Patent Application Laid-Open No. 2003-147152 [Patent Document 3] Japanese Patent Application Publication No. 2017-145365 [Patent Document 4] International Publication No. 2016 / 104259 Summary of the Invention [Problem to be solved by the invention]

[0010] An object of the present invention is to provide a thermoplastic resin composition that is excellent in productivity for sheet molding and that can give molded articles that are excellent in chemical resistance, transparency, rigidity, and heat resistance. [Means for solving the problem]

[0011] The present inventors have found that a thermoplastic resin composition containing a specific vinyl copolymer, a rubber-reinforced graft copolymer, and a polyamide elastomer in predetermined proportions can solve the above problems. That is, the present invention is summarized as follows.

[0012] [1] A vinyl copolymer (A) obtained by copolymerizing a vinyl monomer mixture (ma) containing an aromatic vinyl monomer (a1) and a (meth)acrylic acid ester monomer (a2), a rubber-reinforced graft copolymer (B) obtained by graft copolymerizing a vinyl-based monomer mixture (mb) containing at least an aromatic vinyl-based monomer (b1), a (meth)acrylic acid ester-based monomer (b2), and a vinyl cyanide-based monomer (b3) in the presence of a rubber polymer (r); Polyamide elastomer (C) and A thermoplastic resin composition comprising: The vinyl copolymer (A) is obtained by copolymerizing a vinyl monomer mixture (ma1) containing an aromatic vinyl monomer (a1), a (meth)acrylic acid ester monomer (a2), and a vinyl cyanide monomer (a3), and includes a vinyl copolymer (A1) having a weight average molecular weight of 50,000 to 300,000; per 100 parts by mass of the total of the vinyl copolymer (A), the rubber-reinforced graft copolymer (B), and the polyamide elastomer (C), a total of 60 to 92 parts by mass of a vinyl copolymer (A) and a rubber-reinforced graft copolymer (B); 8 to 40 parts by mass of polyamide elastomer (C) A thermoplastic resin composition comprising:

[0013] [2] Per 100 parts by mass of the total of the vinyl copolymer (A), the rubber-reinforced graft copolymer (B), and the polyamide elastomer (C), The thermoplastic resin composition according to [1], comprising 20 to 65 parts by mass of a vinyl copolymer (A), 5 to 72 parts by mass of a rubber-reinforced graft copolymer (B), and 8 to 30 parts by mass of a polyamide elastomer (C).

[0014] [3] A vinyl copolymer (A) obtained by copolymerizing a vinyl monomer mixture (ma) containing an aromatic vinyl monomer (a1) and a (meth)acrylic acid ester monomer (a2), a rubber-reinforced graft copolymer (B) obtained by graft copolymerizing a vinyl-based monomer mixture (mb) containing at least an aromatic vinyl-based monomer (b1), a (meth)acrylic acid ester-based monomer (b2), and a vinyl cyanide-based monomer (b3) in the presence of a rubber polymer (r); Polyamide elastomer (C) and A thermoplastic resin composition comprising: The vinyl copolymer (A) is obtained by copolymerizing a vinyl monomer mixture (ma1) containing an aromatic vinyl monomer (a1), a (meth)acrylic acid ester monomer (a2), and a vinyl cyanide monomer (a3), and includes a vinyl copolymer (A1) having a weight average molecular weight of 100,000 to 250,000; per 100 parts by mass of the total of the vinyl copolymer (A), the rubber-reinforced graft copolymer (B), and the polyamide elastomer (C), 20 to 40 parts by mass of a vinyl copolymer (A), 47 to 65 parts by mass of a rubber-reinforced graft copolymer (B), 8 to 13 parts by mass of a polyamide elastomer (C), Vinyl copolymer (A1) 35 parts by mass or less The thermoplastic resin composition according to [1] or [2],

[0015] [4] The vinyl copolymer (A) further contains a vinyl copolymer (A2) having a weight average molecular weight of 100,000 to 250,000, which is obtained by copolymerizing a vinyl monomer mixture (ma2) containing an aromatic vinyl monomer (a1), a (meth)acrylic acid ester monomer (a2), and a maleimide monomer (a4); The thermoplastic resin composition according to any one of [1] to [3], comprising 20 parts by mass or less of the vinyl copolymer (A2) per 100 parts by mass of the vinyl copolymer (A), the rubber-reinforced graft copolymer (B), and the polyamide elastomer (C) combined.

[0016] [5] The refractive indexes of the vinyl copolymer (A), the acetone-soluble component of the rubber-reinforced graft copolymer (B), and the polyamide elastomer (C) are in the range of 1.505 to 1.520; The thermoplastic resin composition according to any one of [1] to [4], wherein the difference in refractive index between these components is 0.03 or less.

[0017] [6] The thermoplastic resin composition according to any one of [1] to [5], wherein the content of the vinyl cyanide monomer component in 100% by mass of the acetone soluble matter of the thermoplastic resin composition is 0.5 to 10% by mass.

[0018] [7] A molded article made of the thermoplastic resin composition according to any one of [1] to [6].

[0019] [8] The molded product according to [7], which is a sheet-shaped molded product. [Effects of the Invention]

[0020] The thermoplastic resin composition of the present invention is excellent in productivity for sheet molding, and can provide molded articles, particularly sheet-shaped molded articles, that are excellent in chemical resistance, transparency, rigidity, and heat resistance. DETAILED DESCRIPTION OF THE INVENTION

[0021] Hereinafter, an embodiment of the present invention will be described in detail.

[0022] In this specification, the term "molded article" means an article obtained by molding a thermoplastic resin composition. As used herein, "(co)polymer" and "(co)polymer" mean "homopolymer" and / or "copolymer," and "homopolymer" and / or "copolymer," respectively. "(Meth)acrylic" and "(meth)acrylate" mean "acrylic" and / or "methacrylic," and "acrylate" and / or "methacrylate," respectively. Hereinafter, "sheet molding productivity" may be simply referred to as "sheet moldability."

[0023] [Thermoplastic resin composition] The thermoplastic resin composition of the present invention comprises: a vinyl copolymer (A) obtained by copolymerizing a vinyl monomer mixture (ma) containing an aromatic vinyl monomer (a1) and a (meth)acrylic acid ester monomer (a2); a rubber-reinforced graft copolymer (B) obtained by graft copolymerizing a vinyl-based monomer mixture (mb) containing at least an aromatic vinyl-based monomer (b1), a (meth)acrylic acid ester-based monomer (b2), and a vinyl cyanide-based monomer (b3) in the presence of a rubber polymer (r); Polyamide elastomer (C) and A thermoplastic resin composition comprising: The vinyl copolymer (A) is obtained by copolymerizing a vinyl monomer mixture (ma1) containing an aromatic vinyl monomer (a1), a (meth)acrylic acid ester monomer (a2), and a vinyl cyanide monomer (a3), and includes a vinyl copolymer (A1) having a weight average molecular weight of 50,000 to 300,000; per 100 parts by mass of the total of the vinyl copolymer (A), the rubber-reinforced graft copolymer (B), and the polyamide elastomer (C), a total of 60 to 92 parts by mass of a vinyl copolymer (A) and a rubber-reinforced graft copolymer (B); 8 to 40 parts by mass of polyamide elastomer (C) It is characterized by containing Hereinafter, the rubber-reinforced graft copolymer (B) may be simply referred to as "graft copolymer (B)".

[0024] The thermoplastic resin composition of the present invention contains a vinyl copolymer (A) containing the vinyl copolymer (A1), a rubber-reinforced graft copolymer (B), and a polyamide elastomer (C) in predetermined proportions, and the weight-average molecular weight of the vinyl copolymer (A1) is 50,000 to 300,000, thereby improving the transparency, rigidity, and heat resistance of the resulting molded article. Furthermore, the inclusion of the rubber-reinforced graft copolymer (B) improves the chemical resistance of the molded article and fluidity suitable for sheet molding. Furthermore, the inclusion of the polyamide elastomer (C) improves the chemical resistance of the molded article.

[0025] <Vinyl copolymer (A)> The vinyl copolymer (A) is obtained by copolymerizing a vinyl monomer mixture (ma) containing an aromatic vinyl monomer (a1) and a (meth)acrylic acid ester monomer (a2). The vinyl copolymer (A) is obtained by copolymerizing a vinyl monomer mixture (ma1) containing an aromatic vinyl monomer (a1), a (meth)acrylic acid ester monomer (a2), and a vinyl cyanide monomer (a3), and includes a vinyl copolymer (A1) having a weight average molecular weight of 50,000 to 300,000.

[0026] The vinyl copolymer (A) is preferably a vinyl copolymer (A1) and The vinyl copolymer (A2) is obtained by copolymerizing a vinyl monomer mixture (ma2) containing an aromatic vinyl monomer (a1), a (meth)acrylic acid ester monomer (a2), and a maleimide monomer (a4), and has a weight average molecular weight of 100,000 to 250,000, in a suitable content described below.

[0027] That is, the vinyl copolymer (A) may consist only of the vinyl copolymer (A1) and not contain the vinyl copolymer (A2), or may contain both the vinyl copolymer (A1) and the vinyl copolymer (A2). In the present invention, the vinyl copolymer (A1) may be used alone or in a mixture of two or more types having different monomer compositions, physical properties, etc. The vinyl copolymer (A2) may also be used alone or in a mixture of two or more types having different monomer compositions, physical properties, etc.

[0028] (Vinyl copolymer (A1)) The vinyl copolymer (A1) is a copolymer of a vinyl monomer mixture (ma1) containing an aromatic vinyl monomer (a1), a (meth)acrylic acid ester monomer (a2), and a vinyl cyanide monomer (a3). The vinyl copolymer (A1) is preferably obtained by copolymerizing a vinyl monomer mixture (ma1) containing 5 to 40% by mass of the aromatic vinyl monomer (a1), 30 to 85% by mass of the (meth)acrylic acid ester monomer (a2), and 2 to 30% by mass of the vinyl cyanide monomer (a3) ​​according to a conventional method. The vinyl monomer mixture (ma1) may further contain another vinyl copolymer copolymerizable with the aromatic vinyl monomer (a1), the (meth)acrylic acid ester monomer (a2), and the vinyl cyanide monomer (a3).

[0029] Examples of the aromatic vinyl monomer (a1) include styrene, α-methylstyrene, p-methylstyrene, m-methylstyrene, o-methylstyrene, vinyltoluene, and t-butylstyrene. These may be used alone or in combination of two or more. Among these, styrene is preferred from the viewpoint of improving the moldability of the thermoplastic resin composition and the rigidity of the resulting molded article.

[0030] The content of the aromatic vinyl monomer (a1) in the vinyl monomer mixture (ma1) is preferably 5% by mass or more, more preferably 10% by mass or more, and even more preferably 19% by mass or more, based on 100% by mass of the total vinyl monomer mixture (ma1). If the content of the aromatic vinyl monomer (a1) is equal to or higher than the above lower limit, the moldability of the thermoplastic resin composition (A1) and the rigidity of the resulting molded article can be further improved. The content of the aromatic vinyl monomer (a1) in the vinyl monomer mixture (ma1) is preferably 40% by mass or less, more preferably 30% by mass or less, and even more preferably 27% by mass or less, based on 100% by mass of the total vinyl monomer mixture (ma1). If the content of the aromatic vinyl monomer (a1) is equal to or lower than the above upper limit, the impact resistance and transparency of the resulting molded article can be further improved.

[0031] The (meth)acrylic acid ester monomer (a2) is not particularly limited, but is preferably an ester of an alcohol having 1 to 6 carbon atoms with acrylic acid or methacrylic acid. The ester of an alcohol having 1 to 6 carbon atoms with acrylic acid or methacrylic acid may further have a substituent such as a hydroxyl group or a halogen group. Examples of the ester of an alcohol having 1 to 6 carbon atoms with acrylic acid or methacrylic acid include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, n-butyl (meth)acrylate, t-butyl (meth)acrylate, n-hexyl (meth)acrylate, cyclohexyl (meth)acrylate, chloromethyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2,3,4,5,6-pentahydroxyhexyl (meth)acrylate, and 2,3,4,5-tetrahydroxypentyl (meth)acrylate. These may be used alone or in combination of two or more. Among these, methyl (meth)acrylate is preferred from the viewpoint of improving the transparency of the resulting molded article.

[0032] The content of the (meth)acrylic acid ester monomer (a2) in the vinyl-based monomer mixture (ma1) is preferably 30% by mass or more, more preferably 50% by mass or more, and even more preferably 65% ​​by mass or more, based on 100% by mass of the total vinyl-based monomer mixture (ma1). If the content of the (meth)acrylic acid ester monomer (a2) is equal to or higher than the above-mentioned lower limit, the transparency of the resulting molded article can be further improved. The content of the (meth)acrylic acid ester monomer (a2) in the vinyl-based monomer mixture (ma1) is preferably 85% by mass or less, more preferably 80% by mass or less, and even more preferably 75% by mass or less, based on 100% by mass of the total vinyl-based monomer mixture (ma1). If the content of the (meth)acrylic acid ester monomer (a2) is equal to or lower than the above-mentioned upper limit, the chemical resistance and transparency of the resulting molded article can be further improved.

[0033] Examples of the vinyl cyanide monomer (a3) ​​include acrylonitrile, methacrylonitrile, and ethacrylonitrile. These may be used alone or in combination of two or more. Among these, acrylonitrile is preferred from the viewpoint of further improving the chemical resistance of the resulting molded article.

[0034] The content of the vinyl cyanide monomer (a3) ​​in the vinyl monomer mixture (ma1) is preferably 2 to 30% by mass, based on a total of 100% by mass of the vinyl monomer mixture (ma1). If the content of the vinyl cyanide monomer (a3) ​​is less than 2% by mass, chemical resistance tends to decrease. Therefore, the content of the vinyl cyanide monomer (a3) ​​is preferably 2% by mass or more, more preferably 5% by mass or more, and even more preferably 6% by mass or more. On the other hand, if the content of the vinyl cyanide monomer (a3) ​​exceeds 30% by mass, the yellowness index (YI) of the resulting molded article tends to increase and the color tone tends to decrease. Therefore, the content of the vinyl cyanide monomer (a3) ​​in the vinyl monomer mixture (ma1) is preferably 30% by mass or less, more preferably 20% by mass or less, even more preferably 10% by mass or less, particularly 9% by mass or less, and most preferably 8% by mass or less.

[0035] Other vinyl copolymers copolymerizable with these are vinyl monomers other than the above-mentioned aromatic vinyl monomer (a1), (meth)acrylic acid ester monomer (a2), and vinyl cyanide monomer (a3), and are not particularly limited as long as they do not impair the effects of the present invention. Specific examples include unsaturated fatty acids, acrylamide monomers, and maleimide monomers. These may be used alone or in combination of two or more.

[0036] Examples of unsaturated fatty acids include itaconic acid, maleic acid, fumaric acid, butenoic acid, acrylic acid, and methacrylic acid. Examples of the acrylamide monomer include acrylamide, methacrylamide, and N-methylacrylamide. Examples of maleimide monomers include N-methylmaleimide, N-ethylmaleimide, N-isopropylmaleimide, N-butylmaleimide, N-hexylmaleimide, N-octylmaleimide, N-dodecylmaleimide, N-cyclohexylmaleimide, and N-phenylmaleimide.

[0037] When the vinyl monomer mixture (ma1) contains these other vinyl copolymers, the content of the other vinyl copolymers in 100% by mass of the vinyl monomer mixture (ma1) is preferably 10% by mass or less, more preferably 0 to 5% by mass. When the content of the other vinyl copolymers is not more than the above upper limit, the effect of using the aromatic vinyl monomer (a1), the (meth)acrylic acid ester monomer (a2) and the vinyl cyanide monomer (a3) ​​in a predetermined ratio can be effectively obtained.

[0038] (Vinyl copolymer (A2)) The vinyl copolymer (A2) is a copolymer of a vinyl monomer mixture (ma2) containing an aromatic vinyl monomer (a1), a (meth)acrylic acid ester monomer (a2), and a maleimide monomer (a4). The vinyl copolymer (A2) is preferably obtained by copolymerizing a vinyl monomer mixture (ma2) containing 2 to 30% by mass of the aromatic vinyl monomer (a1), 30 to 80% by mass of the (meth)acrylic acid ester monomer (a2), and 10 to 50% by mass of the maleimide monomer (a4) according to a conventional method. The vinyl monomer mixture (ma2) may further contain other monomers copolymerizable with the aromatic vinyl monomer (a1), the (meth)acrylic acid ester monomer (a2), and the maleimide monomer (a4).

[0039] Examples of the aromatic vinyl monomer (a1) include those exemplified as the aromatic vinyl monomer (a1) used in the vinyl copolymer (A1). As the aromatic vinyl monomer (a1), styrene is preferred.

[0040] The content of the aromatic vinyl monomer (a1) in the vinyl monomer mixture (ma2) is preferably 2% by mass or more, more preferably 5% by mass or more, based on 100% by mass of the total vinyl monomer mixture (ma2). If the content of the aromatic vinyl monomer (a1) is equal to or higher than the above lower limit, the moldability of the thermoplastic resin composition and the rigidity of the resulting molded article can be further improved. The content of the aromatic vinyl monomer (a1) in the vinyl monomer mixture (ma2) is preferably 30% by mass or less, more preferably 20% by mass or less, and even more preferably 15% by mass or less, based on 100% by mass of the total vinyl monomer mixture (ma2). If the content of the aromatic vinyl monomer (a1) is equal to or lower than the above upper limit, the impact resistance and transparency of the resulting molded article can be further improved.

[0041] Examples of the (meth)acrylic acid ester monomer (a2) include those exemplified as the (meth)acrylic acid ester monomer (a2) used in the vinyl copolymer (A1). As the (meth)acrylic acid ester monomer (a2), methyl (meth)acrylate is preferred.

[0042] The content of the (meth)acrylic acid ester monomer (a2) in the vinyl-based monomer mixture (ma2) is preferably 30% by mass or more, more preferably 50% by mass or more, and even more preferably 55% by mass or more, based on 100% by mass of the total vinyl-based monomer mixture (ma2). When the content of the (meth)acrylic acid ester monomer (a2) is equal to or greater than the above-mentioned lower limit, the transparency of the resulting molded article can be further improved. When the content of the (meth)acrylic acid ester monomer (a2) in the vinyl-based monomer mixture (ma2) is equal to or less than 80% by mass, more preferably equal to or less than 75% by mass, and even more preferably equal to or less than 70% by mass, based on 100% by mass of the total vinyl-based monomer mixture (ma2). When the content of the (meth)acrylic acid ester monomer (a2) is equal to or less than the above-mentioned upper limit, the chemical resistance of the resulting molded article can be further improved.

[0043] Examples of the maleimide monomer (a4) include those exemplified as maleimide monomers for other vinyl copolymers that may be used as needed in the vinyl copolymer (A1). Preferred examples of the maleimide monomer (a4) include N-phenylmaleimide.

[0044] The content of the maleimide monomer (a4) in the vinyl monomer mixture (ma2) is preferably 10 to 50% by mass, based on a total of 100% by mass of the vinyl monomer mixture (ma2). If the content of the maleimide monomer (a4) is less than 10% by mass, heat resistance tends to decrease. Therefore, the content of the maleimide monomer (a4) is preferably 10% by mass or more, more preferably 15% by mass or more. If the content of the maleimide monomer (a4) exceeds 50% by mass, the fluidity of the thermoplastic resin composition tends to decrease. Therefore, the content of the maleimide monomer (a4) is preferably 50% by mass or less, more preferably 35% by mass or less, and even more preferably 30% by mass or less.

[0045] Other vinyl copolymers copolymerizable with these are vinyl monomers other than the above-mentioned aromatic vinyl monomer (a1), (meth)acrylic acid ester monomer (a2), and maleimide monomer (a4), and are not particularly limited as long as they do not impair the effects of the present invention. Specific examples include vinyl cyanide monomers, unsaturated fatty acids, and acrylamide monomers.

[0046] Examples of the vinyl cyanide monomer include those exemplified as the vinyl cyanide monomer (a3) ​​used in the vinyl copolymer (A1).

[0047] Examples of the unsaturated fatty acid and acrylamide monomer include those exemplified as other vinyl copolymers used in the vinyl copolymer (A1).

[0048] When the vinyl monomer mixture (ma2) contains these other vinyl copolymers, the content of the other vinyl copolymers in 100% by mass of the vinyl monomer mixture (ma2) is preferably 10% by mass or less, more preferably 0 to 5% by mass. When the content of the other vinyl copolymers is not more than the above upper limit, the effect of using the aromatic vinyl monomer (a1), the (meth)acrylic acid ester monomer (a2), and the maleimide monomer (a4) in a predetermined ratio can be effectively obtained.

[0049] (Physical properties of vinyl copolymer (A)) In the present invention, the weight average molecular weight (Mw) of the vinyl copolymer (A1) is 50,000 to 300,000, preferably 100,000 to 250,000. The weight average molecular weight (Mw) of the vinyl copolymer (A2) is preferably 100,000 to 250,000. When the weight average molecular weights of the vinyl copolymer (A1) and the vinyl copolymer (A2) are each at least the lower limit, the resulting thermoplastic resin composition has low fluidity and excellent sheet formability. When the weight average molecular weights of the vinyl copolymer (A1) and the vinyl copolymer (A2) are each above the upper limit, the flow rate tends to be too low, resulting in poor sheet formability. The vinyl copolymer (A1) having a weight average molecular weight (Mw) of 50,000 to 300,000 and the vinyl copolymer (A2) having a weight average molecular weight (Mw) of 100,000 to 250,000 can be easily produced, for example, by using an initiator or chain transfer agent described later and by setting the polymerization temperature within the preferred range described later.

[0050] The refractive index of the vinyl copolymer (A) is preferably 1.505 to 1.520, more preferably 1.509 to 1.519, and even more preferably 1.510 to 1.517. When the refractive index of the vinyl copolymer (A) is within the above range, the difference in refractive index between the vinyl copolymer (A) and the rubber-reinforced graft copolymer (B) described below can be reduced, and the transparency of the resulting molded article can be improved.

[0051] From the viewpoint of the transparency of the molded article obtained, it is preferable that the difference between the refractive index of the vinyl copolymer (A) and the refractive index of the acetone-soluble portion of the rubber-reinforced graft copolymer (B) described below and the refractive index of the polyamide elastomer (C) is 0.03 or less, particularly 0.01 or less.

[0052] The refractive index of the vinyl copolymer (A) mainly depends on the composition of the vinyl monomers used as raw materials. Therefore, the refractive index can be adjusted to a desired range by appropriately selecting the type and composition ratio of the vinyl monomers.

[0053] The weight average molecular weight (Mw) and refractive index of the vinyl copolymer (A) are measured by the method described in the Examples section below.

[0054] (Method for producing vinyl copolymer (A)) The method for producing the vinyl copolymer (A) is not particularly limited, and it can be produced by a known polymerization method using the above-mentioned vinyl monomer mixture (ma) (vinyl monomer mixture (ma1) or vinyl monomer mixture (ma2)) as a raw material. From the viewpoint of improving the moldability, transparency, and color stability of the resulting thermoplastic resin composition, a continuous bulk polymerization method or a continuous solution polymerization method is preferably used.

[0055] Any method can be used to produce the vinyl copolymer (A) by continuous bulk polymerization or continuous solution polymerization, for example, a method in which a vinyl monomer mixture (ma) is polymerized in a polymerization tank and then subjected to demonomerization (desolvent and devolatilization).

[0056] <Rubber-reinforced graft copolymer (B)> The graft copolymer (B) is obtained by graft copolymerizing a vinyl monomer mixture (mb) containing at least an aromatic vinyl monomer (b1), a (meth)acrylic acid ester monomer (b2) and a vinyl cyanide monomer (b3) in the presence of a rubber polymer (r). The graft copolymer (B) is preferably obtained by graft copolymerizing a vinyl monomer mixture (mb) containing 5 to 40 mass% of an aromatic vinyl monomer (b1), 30 to 85 mass% of a (meth)acrylic acid ester monomer (b2), and 2 to 30 mass% of a vinyl cyanide monomer (b3) in the presence of a rubbery polymer (r). The vinyl monomer mixture (mb) may further contain another vinyl copolymer copolymerizable with the aromatic vinyl monomer (b1), the (meth)acrylic acid ester monomer (b2), and the vinyl cyanide monomer (b3).

[0057] Examples of the rubbery polymer (r) include polybutadiene, polyisoprene, butyl rubber, styrene-butadiene copolymer (preferably having a styrene content of 5 to 60% by mass), styrene-isoprene copolymer, acrylonitrile-butadiene copolymer, ethylene-α-olefin copolymer, ethylene-α-olefin-polyene copolymer, silicone rubber, acrylic rubber, butadiene-(meth)acrylate copolymer, polyisoprene, styrene-butadiene block copolymer, styrene-isoprene block copolymer, hydrogenated styrene-butadiene block copolymer, hydrogenated butadiene polymer, ethylene ionomer, etc. The styrene-butadiene block copolymer and styrene-isoprene block copolymer include those having an AB type, ABA type, tapered type, or radial teleblock type structure. In addition to the hydrogenated block copolymers, the hydrogenated butadiene polymers include hydrogenated products of a polystyrene block and a styrene-butadiene random copolymer block; and hydrogenated products of a polymer comprising a polybutadiene block having a 1,2-vinyl bond content of 20% by mass or less and a polybutadiene block having a 1,2-vinyl bond content of more than 20% by mass.

[0058] Among these, polybutadiene and ethylene-α-olefin copolymers are often used as the rubber polymer (r).

[0059] These rubbery polymers (r) may be used alone or in combination of two or more.

[0060] The amount of rubbery polymer (r) used is preferably 20 to 80 parts by mass relative to 100 parts by mass of the total amount of the rubbery polymer (r) and the vinyl monomer mixture (mb) described below that constitute the rubber-reinforced graft copolymer (B). If the amount of rubbery polymer (r) used is 20 parts by mass or more, the impact resistance of the resulting molded article can be further improved. The content of rubbery polymer (r) is more preferably 35 parts by mass or more. If the content of rubbery polymer (r) is 80 parts by mass or less, the moldability of the thermoplastic resin composition can be further improved. The content of rubbery polymer (r) is more preferably 60 parts by mass or less.

[0061] The volume average particle diameter of the rubbery polymer (r) is not particularly limited, but from the viewpoint of further improving the impact resistance of the obtained molded article, it is preferably 80 nm or more, more preferably 150 nm or more. From the viewpoint of improving the transparency of the obtained molded article, the volume average particle diameter of the rubbery polymer (r) is preferably 500 nm or less, more preferably 350 nm or less, and even more preferably 300 nm or less.

[0062] The volume average particle diameter of the rubber polymer (r) and the rubber-reinforced graft copolymer (B) described later is measured by the method described in the Examples section below.

[0063] Examples of the aromatic vinyl monomer (b1) include those exemplified as the aromatic vinyl monomer (a1). As the aromatic vinyl monomer (b1), styrene is preferred.

[0064] The content of the aromatic vinyl monomer (b1) in the vinyl monomer mixture (mb) is preferably 5% by mass or more, more preferably 10% by mass or more, based on 100% by mass of the total vinyl monomer mixture (mb). When the content of the aromatic vinyl monomer (b1) is equal to or more than the above lower limit, the moldability of the thermoplastic resin composition and the rigidity of the resulting molded article can be further improved. The content of the aromatic vinyl monomer (b1) in the vinyl monomer mixture (mb) is preferably 40% by mass or less, more preferably 30% by mass or less, based on 100% by mass of the total vinyl monomer mixture (mb). When the content of the aromatic vinyl monomer (b1) is equal to or less than the above upper limit, the impact resistance and transparency of the resulting molded article can be further improved.

[0065] Examples of the (meth)acrylic acid ester monomer (b2) include those exemplified as the (meth)acrylic acid ester monomer (a2). As the (meth)acrylic acid ester monomer (b2), methyl (meth)acrylate is preferred.

[0066] The content of the (meth)acrylic acid ester monomer (b2) in the vinyl-based monomer mixture (mb) is preferably 30% by mass or more, more preferably 50% by mass or more, based on 100% by mass of the total vinyl-based monomer mixture (mb). When the content of the (meth)acrylic acid ester monomer (b2) is equal to or higher than the above-mentioned lower limit, the transparency of the resulting molded article can be further improved. When the content of the (meth)acrylic acid ester monomer (b2) in the vinyl-based monomer mixture (mb) is equal to or lower than 85% by mass, more preferably equal to or lower than 75% by mass, based on 100% by mass of the total vinyl-based monomer mixture (mb). When the content of the (meth)acrylic acid ester monomer (b2) is equal to or lower than the above-mentioned upper limit, the chemical resistance of the resulting molded article can be further improved.

[0067] Examples of the vinyl cyanide monomer (b3) include those exemplified as the vinyl cyanide monomer (a3). As the vinyl cyanide monomer (b3), acrylonitrile is preferred.

[0068] The content of the vinyl cyanide monomer (b3) in the vinyl monomer mixture (mb) is preferably 2 to 30% by mass, based on a total of 100% by mass of the vinyl monomer mixture (mb). If the content of the vinyl cyanide monomer (b3) is less than 2% by mass, the chemical resistance and impact resistance of the resulting molded article tend to be reduced. Therefore, the content of the vinyl cyanide monomer (b3) is preferably 2% by mass or more, more preferably 5% by mass or more. If the content of the vinyl cyanide monomer (b3) exceeds 30% by mass, the yellowness index (YI) of the resulting molded article tends to increase, resulting in a reduced color tone. Therefore, the content of the vinyl cyanide monomer unit (b3) is preferably 30% by mass or less, more preferably 20% by mass or less.

[0069] The other monomer copolymerizable therewith is not particularly limited as long as it is a vinyl monomer other than the above-mentioned aromatic vinyl monomer (b1), (meth)acrylic acid ester monomer (b2), and vinyl cyanide monomer (b3), and does not impair the effects of the present invention. Specific examples include those exemplified as other monomers in the vinyl monomer mixture (ma1). When the vinyl monomer mixture (mb) contains these other monomers, the content thereof is preferably 10% by mass or less, more preferably 0 to 5% by mass.

[0070] The weight average molecular weight (Mw) of the acetone soluble portion of the rubber-reinforced graft copolymer (B) is preferably 30,000 to 500,000, more preferably 40,000 to 250,000, and even more preferably 50,000 to 150,000. The rubber-reinforced graft copolymer (B) having a weight average molecular weight of 30,000 to 500,000 can be easily produced, for example, by using an initiator or chain transfer agent described later and by setting the polymerization temperature within the preferred range described later.

[0071] The graft ratio of the rubber-reinforced graft copolymer (B) is not particularly limited, but from the viewpoint of further improving the impact resistance of the resulting molded article, it is preferably from 10 to 150%, more preferably from 40 to 120%.

[0072] The volume average particle size of the rubber-reinforced graft copolymer (B) is preferably 80 to 500 nm, particularly preferably 100 to 300 nm, from the viewpoint of transparency.

[0073] The refractive index of the acetone soluble portion of the rubber-reinforced graft copolymer (B) is preferably 1.505 to 1.520, more preferably 1.509 to 1.519, and even more preferably 1.510 to 1.517. When the refractive index of the acetone soluble portion of the rubber-reinforced graft copolymer (B) is within the above range, a rubber-reinforced graft copolymer (B) with excellent transparency can be obtained.

[0074] As mentioned above, it is preferable that the difference in refractive index between the acetone-soluble components of the vinyl copolymer (A) and the rubber-reinforced graft copolymer (B) and the polyamide elastomer (C) described below is 0.03 or less, particularly 0.01 or less, from the viewpoint of the transparency of the resulting molded article.

[0075] The graft ratio of the graft copolymer (B) and the refractive index of the acetone soluble portion are measured by the method described in the Examples section below.

[0076] In the present invention, the difference in refractive index between the acetone-soluble component, which is the graft component of the rubber-reinforced graft copolymer (B), and the rubbery polymer (r) is preferably 0.03 or less, more preferably 0.01 or less. By making the difference between the refractive index of the rubber-reinforced graft copolymer (B) and the refractive index of the graft component and the rubbery polymer (r) 0.03 or less, the transparency of the resulting molded article can be improved.

[0077] The refractive index of the graft component of the rubber-reinforced graft copolymer (B) depends mainly on the composition of the vinyl monomers used as raw materials. Therefore, the refractive index can be adjusted to the desired range by appropriately selecting the type and composition ratio of the vinyl monomer mixture (mb). In particular, when the polymerization conversion rate is 95% or higher using the emulsion polymerization method, the composition of the graft component becomes almost the same as the composition of the vinyl monomer mixture (mb).

[0078] The refractive index of rubbery polymers (r) is generally given in the literature, e.g., 1.516 for polybutadiene rubber.

[0079] The refractive index of the graft component of the graft copolymer (B) can be measured in the same manner as for the vinyl copolymer (A) for the graft component obtained by dissolving the graft copolymer (B) in acetone, filtering the acetone-soluble component, and drying the residue.

[0080] In the present invention, the method for producing the graft copolymer (B) is not particularly limited, and any method such as emulsion polymerization, suspension polymerization, continuous bulk polymerization, or continuous solution polymerization can be used. Among these, emulsion polymerization or bulk polymerization is preferred, and emulsion polymerization is more preferred. With emulsion polymerization, the particle size of the rubbery polymer (r) can be easily adjusted to a desired range, and polymerization stability can be easily adjusted by heat removal during polymerization.

[0081] When the graft copolymer (B) is produced by emulsion polymerization, the method for charging the rubber polymer (r) and the vinyl monomer mixture (mb) is not particularly limited. For example, they may all be charged at once at the initial stage. Furthermore, to adjust the copolymer composition distribution, a portion of the vinyl monomer mixture (mb) may be charged continuously, or a portion or all of the vinyl monomer mixture (mb) may be charged in portions. Here, "continuously charging a portion of the vinyl monomer mixture (mb)" means that a portion of the vinyl monomer mixture (mb) is charged initially, and the remainder is charged continuously over time. "Charging a portion or all of the vinyl monomer mixture (mb) in portions" means that a portion or all of the vinyl monomer mixture (mb) is charged at a time later than the initial charging.

[0082] In the present invention, the rubber-reinforced graft copolymer (B) may be used alone or in combination of two or more different rubber polymers (r), vinyl monomer compositions, physical properties, etc.

[0083] <Polyamide elastomer (C)> The polyamide elastomer (C) constituting the thermoplastic resin composition of the present invention is preferably, for example, a graft copolymer or block copolymer of an aminocarboxylic acid or lactam having 6 or more carbon atoms, or a salt of a diamine having 6 or more carbon atoms and a dicarboxylic acid, and a poly(alkylene oxide) glycol. As the poly(alkylene oxide) glycol, polyethylene oxide glycol is preferably used.

[0084] Specific examples of salts of aminocarboxylic acids or lactams having 6 or more carbon atoms, or diamines and dicarboxylic acids having 6 or more carbon atoms include aminocarboxylic acids such as ω-aminocaproic acid, ω-aminoenanthic acid, ω-aminocaprylic acid, ω-aminopergonic acid, ω-aminocapric acid, 11-aminoundecanoic acid, and 12-aminododecanoic acid; lactams such as caprolactam, enantholactam, capryllactam, and laurolactam; nylon salts such as hexamethylenediamine adipate, hexamethylenediamine sebacate, and hexamethylenediamine isophthalate; and the like. Two or more of these may be used.

[0085] Examples of poly(alkylene oxide) glycols include polyethylene oxide glycol, poly(1,2-propylene oxide) glycol, poly(1,3-propylene oxide) glycol, poly(tetramethylene oxide) glycol, poly(hexamethylene oxide) glycol, block or random copolymers of ethylene oxide and propylene oxide, and block or random copolymers of ethylene oxide and tetrahydrofuran. Two or more of these may be used. Furthermore, alkylene oxide adducts of bisphenol A or fatty acids may be copolymerized.

[0086] From the viewpoint of improving the mechanical properties of the polyamide elastomer (C), the number average molecular weight of the poly(alkylene oxide) glycol is preferably 200 or more, more preferably 300 or more. From the viewpoint of further improving chemical resistance, the number average molecular weight of the poly(alkylene oxide) glycol is preferably 6,000 or less, more preferably 4,000 or less.

[0087] Both ends of the poly(alkylene oxide) glycol may be aminated or carboxylated as needed.

[0088] In the present invention, the bond between the aminocarboxylic acid or lactam having 6 or more carbon atoms, or the salt of a diamine having 6 or more carbon atoms and a dicarboxylic acid, and the poly(alkylene oxide) glycol is usually an ester bond or an amide bond, although it is not limited to these.

[0089] A third component, such as a dicarboxylic acid or diamine, can also be used as a reactant. For example, terephthalic acid (a dicarboxylic acid) can be added to bond nylon 6 and polyethylene glycol.

[0090] When a third component such as a dicarboxylic acid or a diamine is used as a reaction component, the dicarboxylic acid is preferably a dicarboxylic acid having 4 to 20 carbon atoms, from the viewpoint of further improving polymerizability, color tone, and physical properties. Examples include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, phthalic acid, naphthalene-2,7-dicarboxylic acid, diphenyl-4,4-dicarboxylic acid, diphenoxyethanedicarboxylic acid, and sodium 3-sulfoisophthalate; alicyclic dicarboxylic acids such as 1,4-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, and dicyclohexyl-4,4-dicarboxylic acid; and aliphatic dicarboxylic acids such as succinic acid, oxalic acid, adipic acid, sebacic acid, and 1,10-decanedicarboxylic acid.

[0091] As the diamine, aromatic, alicyclic and aliphatic diamines can be used, among which the aliphatic diamine hexamethylenediamine is preferably used.

[0092] The method for producing the polyamide elastomer (C) is not particularly limited, and known production methods can be used. For example, in the case of a graft copolymer or a block copolymer containing poly(alkylene oxide) glycol as a constituent component, the following methods (1) to (3) can be mentioned. (1) (i) an aminocarboxylic acid or a salt of a lactam or a diamine having 6 or more carbon atoms and a dicarboxylic acid; (ii) dicarboxylic acid to obtain a polyamide prepolymer having carboxylic acid groups at both ends, (iii) poly(alkylene oxide) glycol Reacting under vacuum (2) A method in which the above compounds (i), (ii), and (iii) are charged into a reaction vessel and reacted at high temperature in the presence or absence of water to produce a carboxylic acid-terminated polyamide elastomer, and then polymerization is carried out under normal or reduced pressure. (3) A method in which the above compounds (i), (ii), and (iii) are simultaneously charged into a reaction vessel, melt-polymerized, and then polymerized all at once under high vacuum.

[0093] From the viewpoint of sheet formability, the melting point of the polyamide elastomer (C) is preferably 140° C. or higher, more preferably 180° C. or higher, and even more preferably 190° C. or higher. There is no particular upper limit to the melting point of the polyamide elastomer (C), but it is usually 220° C. or lower.

[0094] The refractive index of the polyamide elastomer (C) is preferably 1.505 to 1.520, more preferably 1.509 to 1.519, and even more preferably 1.510 to 1.517. When the refractive index of the polyamide elastomer (C) is within the above range, the difference in refractive index between the polyamide elastomer (C) and the rubber-reinforced graft copolymer (B) can be reduced, which is preferable from the viewpoint of the transparency of the resulting molded article.

[0095] As mentioned above, it is preferable that the difference between the refractive index of the vinyl copolymer (A), the refractive index of the acetone-soluble portion of the rubber-reinforced graft copolymer (B), and the refractive index of the polyamide elastomer (C) is 0.03 or less, particularly 0.01 or less, from the viewpoint of the transparency of the resulting molded article.

[0096] The melting point of the polyamide elastomer (C) is measured by the method described in the Examples section below. The refractive index of the polyamide elastomer (C) can be measured by the method described in the Examples section below. However, for commercially available products, catalog values ​​can be used.

[0097] In the present invention, the polyamide elastomer (C) may be used alone or in combination of two or more types having different segment compositions, physical properties, etc. For example, a nylon 6 polyamide elastomer and a nylon 12 polyamide elastomer may be used in combination, or polyamide elastomers with different melting points may be used in combination.

[0098] The polyamide elastomer (C) may be a commercially available product, such as Pellestat M-140, Pellestat NC6321, Pellestat M-330, Pellestat N1200, or Pelestat AS, manufactured by Sanyo Chemical Industries, Ltd.

[0099] <Mixing ratio> The thermoplastic resin composition of the present invention is a thermoplastic resin composition containing 60 to 92 parts by mass of the vinyl copolymer (A) and the rubber-reinforced graft copolymer (B) in total and 8 to 40 parts by mass of the polyamide elastomer (C) relative to 100 parts by mass of the total of the vinyl copolymer (A) (the vinyl copolymer (A) may be only the vinyl copolymer (A1) or may be composed of the vinyl copolymer (A1) and the vinyl copolymer (A2)), the rubber-reinforced graft copolymer (B), and the polyamide elastomer (C) (hereinafter, sometimes referred to as the "total of (A) to (C)").

[0100] (Ratio of vinyl copolymer (A) and rubber-reinforced graft copolymer (B)) In the thermoplastic resin composition of the present invention, the proportion of the vinyl copolymer (A) is preferably 20 to 80 mass%, more preferably 25 to 75 mass%, and even more preferably 30 to 70 mass%, of the total of 100 mass% of the vinyl copolymer (A) and the rubber-reinforced graft copolymer (B). On the other hand, the proportion of the rubber-reinforced graft copolymer (B) is preferably 20 to 80 mass%, more preferably 25 to 75 mass%, and even more preferably 30 to 70 mass%. This is because, when the content ratio of the vinyl copolymer (A) and the rubber-reinforced graft copolymer (B) is within the above range, the chemical resistance and transparency are excellent.

[0101] (The total of vinyl copolymer (A) and rubber-reinforced graft copolymer (B) and the content ratio of polyamide elastomer (C)) The thermoplastic resin composition of the present invention contains 60 to 92 parts by mass of the vinyl copolymer (A) and the rubber-reinforced graft copolymer (B) in total, and 8 to 40 parts by mass of the polyamide elastomer (C), based on a total of 100 parts by mass of (A) to (C). This blending ratio can be adjusted appropriately within the above range depending on the purpose.

[0102] (Rubber content in thermoplastic resin composition) The content of the rubbery polymer (r) in 100% by mass of the thermoplastic resin composition of the present invention (hereinafter sometimes referred to as "rubber content") is preferably 8 to 35% by mass, more preferably 10 to 30% by mass. The lower limit of the content of the rubbery polymer (r) is more preferably 11% by mass or more, particularly preferably 12% by mass or more, and most preferably 13% by mass or more. The upper limit of the content of the rubbery polymer (r) is more preferably 28% by mass or less, particularly preferably 25% by mass or less, and most preferably 23% by mass or less. This is because, when the content of the rubbery polymer (r) in the thermoplastic resin composition is within the above range, the composition has excellent chemical resistance, transparency, and sheet appearance.

[0103] The rubber content in the thermoplastic resin composition can be determined by a method of calculating the content of the rubber polymer (r) in the rubber-reinforced graft copolymer (B) from the compounding ratio, or by measuring the rubber content using an infrared spectroscopic analyzer.

[0104] (Vinyl cyanide monomer content in acetone soluble matter of thermoplastic resin composition) The content of the vinyl cyanide-based monomer component in 100% by mass of the acetone-soluble matter of the thermoplastic resin composition is preferably 0.5 to 10% by mass. If the content of the vinyl cyanide-based monomer component is less than 0.5% by mass, dispersibility will be poor when mixed with the polyamide elastomer (C), making it difficult to obtain antistatic properties. The content of the vinyl cyanide-based monomer component is more preferably 1.0% by mass or more, even more preferably 2.0% by mass or more, particularly preferably 3.0% by mass or more, and most preferably 4.0% by mass or more. On the other hand, if the content of the vinyl cyanide-based monomer component exceeds 10% by mass, processability and transparency during sheet processing will decrease. The content of the vinyl cyanide-based monomer component is more preferably 9.0% by mass or less, even more preferably 8.0% by mass or less, particularly preferably 7.0% by mass or less, and most preferably 6.5% by mass or less, with 6.0% by mass or less, 5.5% by mass or less, and 5.0% by mass or less being more preferred in that order.

[0105] By setting the content of the vinyl cyanide monomer component in 100% by mass of the acetone soluble matter of the thermoplastic resin composition within the above range, it is possible to maintain transparency and also exhibit sufficient chemical resistance during sheet processing, which involves lower shear forces than those used in injection molding.

[0106] The content of the vinyl cyanide monomer component in the acetone soluble matter in the thermoplastic resin composition is measured by preparing a calibration curve or the like in advance using an infrared spectrometer, extracting the acetone soluble polymer, and then measuring it with a measuring device or the like described in the Examples section below.

[0107] In the examples given later, the extraction of the acetone-soluble polymer was carried out as follows. 2 g of each thermoplastic resin composition obtained in the Examples and Comparative Examples was added to 40 mL of acetone, shaken for 2 hours using a shaker at 25°C, and then centrifuged for 60 minutes using a centrifuge (rotation speed: 23,000 rpm) at 5°C to separate the acetone-soluble and acetone-insoluble components. The resulting acetone-soluble components were added dropwise to methanol to precipitate the polymer components, which were then filtered and collected. The solids were dried in a vacuum dryer for 24 hours, and the resulting precipitate was extracted as the acetone-soluble polymer component in the thermoplastic resin composition. The content of the vinyl cyanide monomer component in the acetone soluble matter can be determined by the method of direct extraction and measurement as described above, or by a method of calculating from the blending ratio using the content of the vinyl cyanide monomer component in the acetone soluble matter of each raw material used.

[0108] (Weight average molecular weight of acetone soluble matter in thermoplastic resin composition) The weight-average molecular weight of the acetone-soluble portion of the thermoplastic resin composition is preferably 60,000 to 280,000. This range is preferable because transparency can be maintained during sheet molding and subsequent processing steps. The weight-average molecular weight of the acetone-soluble portion is more preferably 65,000 to 250,000, even more preferably 70,000 to 200,000, and particularly preferably 75,000 to 150,000.

[0109] The weight-average molecular weight of the acetone-soluble portion in the thermoplastic resin composition can be measured as a polystyrene-equivalent value by GPC. The weight-average molecular weight of the acetone-soluble portion can be measured after extracting the acetone-soluble polymer by the above-mentioned method, using a measuring device described in the Examples section below.

[0110] (Content of each ingredient) The thermoplastic resin composition of the present invention preferably contains 20 to 65 parts by mass of vinyl copolymer (A), 5 to 72 parts by mass of rubber-toughened graft copolymer (B), and 8 to 30 parts by mass of polyamide elastomer (C) relative to 100 parts by mass of the total of (A) to (C), more preferably 20 to 60 parts by mass of vinyl copolymer (A), 15 to 72 parts by mass of rubber-toughened graft copolymer (B), and 8 to 25 parts by mass of polyamide elastomer (C), and even more preferably 20 to 55 parts by mass of vinyl copolymer (A), 25 to 72 parts by mass of rubber-toughened graft copolymer (B), and 8 to 20 parts by mass of polyamide elastomer (C). The thermoplastic resin composition of the present invention may contain, relative to 100 parts by mass of the total of (A) to (C), 20 to 40 parts by mass of vinyl copolymer (A), 47 to 65 parts by mass of rubber-toughened graft copolymer (B), 8 to 13 parts by mass of polyamide elastomer (C), and 35 parts by mass or less of vinyl copolymer (A1) in vinyl copolymer (A).

[0111] If the content of the vinyl copolymer (A) in 100 parts by mass of the total of (A) to (C) is less than the above lower limit, the effect of containing the vinyl copolymer (A) in improving the rigidity and heat resistance of the obtained molded article cannot be fully obtained. If the content of the vinyl copolymer (A) exceeds the above upper limit, the moldability of the sheet decreases. The more preferable content of the vinyl copolymer (A) in 100 parts by mass of the total of (A) to (C) is as described above.

[0112] From the viewpoint of transparency and rigidity of the resulting molded article, the content of the vinyl copolymer (A1) in the vinyl copolymer (A) is preferably 35 parts by mass or less, more preferably 30% by mass or less, per 100 parts by mass of the total of (A) to (C). When the vinyl copolymer (A) contains a vinyl copolymer (A1) and a vinyl copolymer (A2), the content of the vinyl copolymer (A2) is preferably 20 parts by mass or less, more preferably 5 to 20 parts by mass, and even more preferably 8 to 18 parts by mass, per 100 parts by mass of the total of (A) to (C), from the viewpoints of heat resistance, chemical resistance, and sheet formability.

[0113] If the content of graft copolymer (B) in 100 parts by mass of the total of (A) to (C) is less than the above lower limit, the effect of containing the rubber-reinforced graft copolymer (B) in improving the chemical resistance of the molded article and the flowability suitable for sheet molding cannot be fully obtained. If the content of graft copolymer (B) exceeds the above upper limit, the effect of improving the rigidity and heat resistance of the molded article cannot be fully obtained. The more preferred content of graft copolymer (B) in 100 parts by mass of the total of (A) to (C) is as described above.

[0114] If the content of polyamide elastomer (C) in a total of 100 parts by mass of (A) to (C) is less than 8 parts by mass, the effect of improving chemical resistance due to the inclusion of polyamide elastomer (C) cannot be fully obtained, and the chemical resistance of the obtained molded article will be reduced. The content of polyamide elastomer (C) is preferably 8 parts by mass or more, and particularly preferably 10 parts by mass or more. On the other hand, from the viewpoint of improving the rigidity of the obtained molded article, the content of polyamide elastomer (C) in a total of 100 parts by mass of (A) to (C) is 40 parts by mass or less, preferably 30 parts by mass or less, more preferably 25 parts by mass or less, even more preferably 20 parts by mass or less, particularly preferably 18 parts by mass or less, and particularly preferably 13 parts by mass or less.

[0115] <Other ingredients> The thermoplastic resin composition of the present invention may contain resins and elastomers other than the vinyl copolymer (A), the graft copolymer (B), and the polyamide elastomer (C) within the range that does not impair the effects of the present invention. These other resins and elastomers include one or more transparent resins such as polycarbonate resins and polymethyl methacrylate.

[0116] When the thermoplastic resin composition of the present invention contains these resins or elastomers, the content thereof is preferably 10 parts by mass or less per 100 parts by mass of the total of the vinyl copolymer (A), the graft copolymer (B), the polyamide elastomer (C), and the other resins or elastomers. When the content is equal to or less than the above upper limit, the effects of the present invention can be effectively obtained by using the vinyl copolymer (A), the graft copolymer (B), and the polyamide elastomer (C) in the predetermined ratio.

[0117] The thermoplastic resin composition of the present invention may also contain, within the scope of the present invention, antioxidants such as hindered phenols, sulfur-containing organic compounds, and phosphorus-containing organic compounds; heat stabilizers such as phenols and acrylates; ultraviolet absorbers such as benzotriazoles, benzophenones, and salicylates; various stabilizers such as organic nickel and hindered amine light stabilizers; lubricants such as metal salts of higher fatty acids and higher fatty acid amides; plasticizers such as phthalates and phosphate esters; anti-drip agents such as polytetrafluoroethylene; nonionic, anionic, cationic, or amphoteric surfactants; pigments and dyes such as carbon black and titanium oxide; and liquids such as water, silicone oil, and liquid paraffin. Fillers may also be added.

[0118] Examples of fillers include fibrous, plate-like, powdery, and granular fillers, and any of these may be used in the present invention. Specific examples include polyacrylonitrile (PAN) and pitch-based carbon fibers; metal fibers such as stainless steel fibers, aluminum fibers, and brass fibers; organic fibers such as aromatic polyamide fibers; fibrous or whisker-like fillers such as gypsum fibers, ceramic fibers, asbestos fibers, zirconia fibers, alumina fibers, silica fibers, titanium oxide fibers, silicon carbide fibers, glass fibers, rock wool, potassium titanate whiskers, barium titanate whiskers, aluminum borate whiskers, and silicon nitride whiskers; and powdery, granular, or plate-like fillers such as mica, talc, kaolin, silica, calcium carbonate, glass flakes, glass beads, glass microballoons, clay, molybdenum disulfide, wollastonite, montmorillonite, titanium oxide, zinc oxide, barium sulfate, calcium polyphosphate, and graphite. Two or more of these may be used. Among these, glass fibers are preferred. The type of glass fiber is not particularly limited as long as it is generally used to reinforce resins, and examples thereof include chopped strands of long fiber type and short fiber type, milled fiber, and the like.

[0119] The surface of the filler may be treated with any coupling agent (e.g., silane-based coupling agent, titanate-based coupling agent, etc.) or other surface treatment agent. The filler may be coated or bundled with a thermoplastic resin such as ethylene / vinyl acetate copolymer or a thermosetting resin such as epoxy resin. The filler may be treated with a coupling agent such as aminosilane or epoxysilane.

[0120] When the thermoplastic resin composition of the present invention contains a filler, the content thereof is preferably 0.01 to 10 parts by mass per 100 parts by mass of the total of the vinyl copolymer (A), the graft copolymer (B), and the polyamide elastomer (C). By setting the content of the filler within the above range, the rigidity and heat resistance of the obtained molded article can be further improved.

[0121] <Method of producing thermoplastic resin composition> There are no particular limitations on the method for producing the thermoplastic resin composition. The thermoplastic resin composition of the present invention is produced by blending the vinyl copolymer (A), the graft copolymer (B), the polyamide elastomer (C), and other components used as needed in the above-mentioned predetermined ratios.

[0122] From the viewpoint of productivity, a method of melt-kneading the vinyl copolymer (A), the graft copolymer (B), the polyamide elastomer (C), and other components as required is generally used. When the above-mentioned additives are blended, the blending method is not particularly limited, and various methods can be used.

[0123] <Method for molding thermoplastic resin composition> The thermoplastic resin composition of the present invention can be molded by known methods such as injection molding, extrusion molding, calendar molding, blow molding, vacuum molding, compression molding, and gas-assisted molding.

[0124] <Physical properties of thermoplastic resin composition> The melt volume rate (MVR) of the thermoplastic resin composition of the present invention, measured by the method described in the Examples section below, is preferably 50 cm from the viewpoint of sheet formability. 3 / 10 minutes or less, preferably 30cm 3 / 10 minutes or less, more preferably 20cm 3 On the other hand, the MVR of the thermoplastic resin composition of the present invention is 2 cm / 10 minutes or less from the viewpoint of sheet formability and sheet appearance. 3 / 10 minutes or more is preferable, 4cm 3 / 10 minutes or more is preferable, and 6cm 3 It is more preferable that the time is 10 minutes or more.

[0125] From the viewpoint of transparency, the total light transmittance of the thermoplastic resin composition of the present invention, measured by the method described in the Examples section below, is preferably 85% or more, and more preferably 87% or more.

[0126] From the viewpoint of rigidity, the flexural modulus of the thermoplastic resin composition of the present invention, measured by the method described in the Examples section below, is preferably 900 MPa or more, and more preferably 1,000 MPa or more.

[0127] From the viewpoint of heat resistance, the heat distortion temperature of the thermoplastic resin composition of the present invention, measured by the method described in the Examples section below, is preferably 58°C or higher, more preferably 60°C or higher, and even more preferably 63°C or higher.

[0128] [Molded products] The molded article of the present invention is obtained by molding the thermoplastic resin composition of the present invention by any of the various molding methods described above. The molded article of the present invention can be used in a wide range of fields, such as home appliances, communication-related equipment, transport containers, general merchandise, and medical-related equipment.

[0129] In particular, the thermoplastic resin composition of the present invention is preferably used as a film or sheet by T-die molding or calendar molding because of its excellent sheet formability, chemical resistance, transparency, rigidity, and heat resistance. The molded article of the present invention is particularly preferred as a conveying device or transport container for precision parts, and in this case, even if chemical solutions such as detergents adhere to the composition, it can maintain high transparency and prevent cracks and breakage. The molded article of the present invention can be widely used not only for general-purpose products such as transparent storage cases, but also as parts for producing industrial products such as photomasks. [Example]

[0130] The present invention will be described in more detail below with reference to examples and comparative examples. The present invention is not limited to the following examples in any way as long as the gist of the invention is not exceeded. In the following description, "parts" means "parts by mass" and "%" means "% by mass".

[0131] [Measurement and evaluation method] The various measurement and evaluation methods used in the following examples and comparative examples are as follows.

[0132] <Volume average particle size> The value was determined by dynamic light scattering using Nanotrac UPA-EX150 manufactured by Nikkiso Co., Ltd.

[0133] <Grafting rate> 1 g (W: sample weight) of graft copolymer (B) was added to 80 mL of acetone and heated to reflux at 65 to 70°C for 3 hours. The resulting acetone suspension was centrifuged at 14,000 rpm for 30 minutes using a centrifuge (Hitachi Koki Co., Ltd., "CR21E") to separate the precipitate (acetone insoluble matter) and the acetone solution (acetone soluble matter). The precipitate (acetone insoluble matter) was then dried and its weight (Q (g)) was measured, and the graft ratio was calculated using the following formula (1): In formula (1), Q is the weight (g) of the acetone-insoluble portion of the graft copolymer (B). W is the total weight (g) of the graft copolymer (B) used to calculate Q. The rubber fraction is the content of the rubbery polymer (r) contained in the graft copolymer (B). Graft rate (%) = {(QW × rubber fraction) / W × rubber fraction} × 100... (1)

[0134] <Polymerization conversion rate> 1 g of the latex of graft copolymer (B) was sampled and weighed, and then dried in a hot air oven at 150°C for 1 hour. The weight after drying was measured as the solid content. The ratio of the weighed weights before and after drying was calculated as the solid content ratio in the latex. Finally, the polymerization conversion rate was calculated using the solid content ratio according to the following formula (2). Polymerization conversion rate (%) = (total weight of raw materials charged × solid component ratio − total weight of raw materials other than monomers) / weight of charged monomer × 100... (2)

[0135] <Infrared spectroscopy> The following measurements (1) and (2) were carried out using an FT-IR "FT-720" Fourier transform infrared spectrophotometer manufactured by Horiba Ltd. (1) Content of vinyl cyanide monomer components in acetone solubles (referred to as "AN content" in Tables 1 to 3). (2) The ratio of the polymer components of the produced vinyl copolymer (A) and rubber-reinforced graft copolymer (B)

[0136] <Weight average molecular weight (Mw)> The weight average molecular weight (Mw) was measured in terms of polystyrene using GPC (GPC: "GPC / V2000" manufactured by Waters, column: "Shodex AT-G+AT-806MS" manufactured by Showa Denko KK).

[0137] <Refractive index> Measurements were taken at 23°C using an Abbe refractometer "KPR-30A" manufactured by Shimadzu Corporation. The refractive index of each copolymer was measured by precipitating and recovering the copolymer from an aqueous dispersion of the vinyl copolymer (A1) or the graft copolymer (B) with isopropyl alcohol, and then drying the copolymer.

[0138] <Glass transition temperature> The glass transition temperature (Tg) of the vinyl copolymer (A-2-1) was measured by differential scanning calorimetry (DSC) by heating a sample from 35°C to 250°C at a rate of 10°C / min under a nitrogen atmosphere, then cooling it to 35°C, and heating it again to 250°C.

[0139] <Melting point (Tm)> According to JIS K 7121-1987, the endothermic change was measured at a constant temperature increase rate of 20°C per minute using a DSC (differential scanning calorimeter), and the peak temperature of the obtained endothermic pattern was taken as the melting point (Tm).

[0140] <Liquidity (MVR)> The MVR of the thermoplastic resin composition obtained by melt-kneading was measured at 220°C and 10 kgf in accordance with ISO 1133. The MVR is an index of the fluidity of the thermoplastic resin composition.

[0141] <Total light transmittance> Measurement was carried out in accordance with ASTM 1003. The thickness of the test piece was 2.5 mm. In addition, the following environmental impacts were assessed: After measuring the total light transmittance of the test piece, the test piece was placed in a constant temperature and humidity chamber at a temperature of 40°C and a humidity of 70% for one week. The test piece was then removed and the total light transmittance was measured again. The difference between the total light transmittance before and after placing in the constant temperature and humidity chamber was confirmed and ranked according to the following criteria. The smaller this difference, the smaller the environmental impact, with A being the most excellent. A: 1% or less B: Over 1% and 3% C: Over 3% and 5% D: More than 5%

[0142] <Sheet molding> Each resin composition was extrusion molded to form a resin sheet of 220 mm (width) x 320 mm (length) x 1 mm (thickness). (Evaluation-1: Seat appearance) The appearance of the resin sheet was visually observed and judged according to the following criteria: A is excellent A: Good (no problems) B: Some minor defects are observed (can be used depending on the application) C: The area where small defects occur is large (usable with very limited applications) D: Defective (cannot be used as a product)

[0143] (Rating -2: Readability: 2D barcode) A 2D barcode (13 x 13 mm) and a smartphone were placed face-to-face and fixed at a distance of 130 mm. A resin sheet was inserted between them, and the resin sheet was moved from the smartphone side to the 2D barcode side. The distance from the 2D barcode to the resin sheet was measured when the smartphone read the 2D barcode. The greater this distance, the easier it is for the image information of the 2D barcode to be transmitted, and the better it is. ND indicates that reading was not possible. This evaluation assumes that the sheet is set up as a product (transparent case) and a part with a 2D barcode is stored inside it, and that it can be read by an external camera.

[0144] <Flexural modulus (rigidity)> Measured according to ISO178.

[0145] <Chemical resistance (bending form method)> Test specimens were molded from the pelletized thermoplastic resin composition using an ESC mold (thickness: 2 mm, width: 12 mm, length: 15 mm) and an injection molding machine ("IS55FP-1.5A" manufactured by Toshiba Machine Co., Ltd.). The test specimens were placed in a constant strain jig with a strain rate of 0.2 to 1.6%, and isopropyl alcohol (Wako Pure Chemical Industries, Ltd.) was dripped onto them. After leaving the test specimens in an atmosphere of 23°C and 50% RH for 48 hours, the test specimens were removed from the jig and the critical strain (%) of the material at which degradation and cracking occurred was determined. The higher the critical strain (%), the better the chemical resistance.

[0146] <Heat distortion temperature (HDT)> According to ASTM D648, load 18.56 kg / cm 2 The heat distortion temperature (HDT) was measured at 1 / 2 inch thickness.

[0147] [Manufacturing and preparation of ingredients] In the following Examples and Comparative Examples, the components used in the production of the thermoplastic resin compositions were produced by the following methods, or the following commercially available products were used.

[0148] <Production of vinyl copolymer (A-1-1)> Two 30-liter stainless steel autoclaves equipped with ribbon blades were connected and purged with nitrogen. Then, 21 parts of styrene, 7 parts of acrylonitrile, 72 parts of methyl methacrylate, and 20 parts of toluene were continuously added to the first reactor. A solution of 0.15 parts of tert-dodecyl mercaptan and 5 parts of toluene as a molecular weight modifier and a solution of 0.1 parts of dicumyl peroxide and 5 parts of toluene as a polymerization initiator were continuously fed. The polymerization temperature of the first reactor was controlled at 110°C, and the average residence time was 2.0 hours. The resulting polymer solution was continuously withdrawn from the first reactor using a pump external to the first reactor in an amount equal to the amount of styrene, acrylonitrile, methyl methacrylate, toluene, molecular weight modifier, and polymerization initiator fed, and then fed to the second reactor. The polymerization temperature of the second reactor was set to 130°C. The copolymer solution obtained in the second reaction vessel was directly subjected to devolatilization of unreacted monomers and solvent using a twin-screw, three-stage vented extruder to obtain a vinyl copolymer (A-1-1). The analytical results of this vinyl copolymer (A-1-1) were as follows: Weight average molecular weight (Mw): 120,000 Refractive index: 1.517

[0149] <Production of vinyl copolymer (A-1-2)> A powdery vinyl copolymer (A-1-2) was obtained in the same manner as in the production of the vinyl copolymer (A-1-1), except that 21 parts of styrene, 13 parts of acrylonitrile, 67 parts of methyl methacrylate, 0.4 parts of tert-dodecyl mercaptan, and 0.1 parts of dicumyl peroxide were used. The analytical results of this vinyl copolymer (A-1-2) were as follows: Weight average molecular weight (Mw): 80,000 Refractive index: 1.517

[0150] <Production of vinyl copolymer (A-1-3)> A vinyl copolymer (A-1-3) was obtained in the same manner as in the production of the vinyl copolymer (A-1-1), except that the amount of tert-dodecyl mercaptan used as a molecular weight modifier was 0.27 parts. The analytical results of this vinyl copolymer (A-1-3) were as follows: Weight average molecular weight (Mw): 85,000 Refractive index: 1.517

[0151] <Vinyl copolymer (A-2-1)> The vinyl copolymer (A-2-1) used was "Polyimilex PML203 (refractive index: 1.516)" manufactured by Nippon Shokubai Co., Ltd. The monomer composition (mass ratio) of the vinyl copolymer (A-2-1) was as follows, and the weight average molecular weight (Mw) and glass transition temperature (Tg) were measured and found to be as follows: Monomer composition: methyl methacrylate / N-phenylmaleimide / styrene = 67 / 28 / 5 (mass ratio) Weight average molecular weight (Mw): 200,000 Glass transition temperature (Tg): 140℃

[0152] <Production of Graft Copolymer (B-1)> A 10 L separable flask equipped with a stirrer was charged with latex (r-1) (solids concentration 50%) containing 45 parts of polybutadiene rubber having a volume average particle size of 280 nm and a gel content of 90%, followed by the addition of 0.5 parts of potassium oleate, 0.2 parts of glucose, 0.2 parts of sodium pyrophosphate, 0.01 parts of ferrous sulfate, and 100 parts of deionized water. The mixture was then heated with stirring, and a monomer mixture consisting of 39.1 parts of methyl methacrylate, 12.7 parts of styrene, 3.2 parts of acrylonitrile, 0.4 parts of diisopropylbenzene hydroperoxide, and 0.8 parts of t-dodecyl mercaptan was continuously added over 5 hours, while polymerization was carried out at 70 °C. The obtained latex was coagulated, washed with water, and dried to obtain a powdery graft copolymer (B-1) containing fine particles of grafted polybutadiene and free methyl methacrylate-styrene-acrylonitrile copolymer (polymerization conversion rate 98%). The grafted polybutadiene (acetone insoluble fraction) obtained by acetone treatment of graft copolymer (B-1) had a graft ratio of 52% and a volume average particle diameter of 260 nm. The free methyl methacrylate-styrene-acrylonitrile copolymer (acetone soluble fraction) had a refractive index of 1.517 and a weight average molecular weight of 54,000.

[0153] <Polyamide elastomer (C)> The polyamide elastomer (C) used was "Pelestat M-140 (refractive index: 1.510)" manufactured by Sanyo Chemical Industries, Ltd., which is a nylon 6-based polyether ester amide block polymer. The melting point of this polyamide elastomer (C) was measured and found to be as follows: Melting point: 192°C

[0154] <Lubricant (D-1)> As the lubricant (D-1), "Alflo H50S" manufactured by NOF Corporation was used.

[0155] <Compatibilizer (E-1)> As the compatibilizer (E-1), an acrylonitrile / α-methylstyrene / acrylic acid copolymer (acrylonitrile / α-methylstyrene / acrylic acid=20 / 75 / 5 (mass ratio)), weight average molecular weight: 67,000) was used.

[0156] <Other ingredients> Polyamide: Toray Industries, Inc. "Amilan CM1017" Polyethylene glycol: Sanyo Chemical Industries, Ltd. "PEG6000S"

[0157] [Examples 1 to 24, Comparative Examples 1 to 8] The components shown in Tables 1 to 3 were blended in the amounts shown in Tables 1 to 3, and 0.00005 parts of Solvent Blue 97 was further blended as a dye, followed by mixing at 23°C using a Henschel mixer. The resulting mixture was melt-kneaded at an extrusion temperature of 230°C using a 30 mmφ twin-screw extruder, extruded into strands, and pelletized. The resulting thermoplastic resin composition pellets were evaluated using the methods described above. The results are shown in Tables 1 to 3.

[0158] [Table 1]

[0159] [Table 2]

[0160] [Table 3]

[0161] The following is clear from Tables 1 to 3. Comparative Examples 1, 2 and 4, which do not contain the polyamide elastomer (C), are significantly inferior in chemical resistance. In Comparative Example 3, in which the polyamide elastomer (C) is contained in a small amount, the chemical resistance is poor. Comparative Example 5, in which polyamide, which is the hard segment of polyamide elastomer (C), was used instead of polyamide elastomer (C), was inferior in transparency, and the sheet appearance and readability were also inferior. In Comparative Example 6, in which polyethylene glycol, which is the soft segment of polyamide elastomer (C), was used instead of polyamide elastomer (C), the fluidity (sheet formability) tended to be poor. Moreover, the transparency, sheet appearance, readability, and heat resistance were extremely poor. Comparative Example 7, which does not contain the vinyl copolymer (A1) component, has an excessively low fluidity value, resulting in poor moldability, and is also poor in transparency, sheet appearance, and readability. Comparative Example 8, which contained an excessive amount of polyamide elastomer (C), had poor transparency, sheet appearance, readability, low rigidity, and also poor chemical resistance. The defects of the compositions shown in these comparative examples are not at a level that can be adjusted by setting conditions such as molding processing, and therefore are not practical.

[0162] In contrast, the thermoplastic resin compositions of Examples 1 to 24, which satisfy the requirements of the present invention, are well-balanced and excellent in all of low fluidity (sheet formability), transparency, sheet appearance, readability, impact resistance, chemical resistance, and heat resistance.

[0163] In Example 7, which contains a sufficient amount of polyamide elastomer (C) but a large amount of graft copolymer (B), the heat resistance is slightly inferior to that of the other Examples. In Example 8, which contains a large amount of vinyl copolymer (A1), the sheet formability tends to be inferior, but these are all at a practical level. Example 9, which contains a relatively large amount of polyamide elastomer (C), tends to have inferior rigidity compared to the other examples, but may be usable depending on the application. In Example 10, which uses a vinyl copolymer (A-1-2) with a weight-average molecular weight of 80,000, the flowability (sheet formability) and chemical resistance tend to be poor, but it is usable.

[0164] Examples 11 to 24 are well-balanced and excellent in all of low fluidity (sheet formability), transparency, impact resistance, chemical resistance, and heat resistance. Furthermore, the environmental impact of total light transmittance is small, the sheet appearance is excellent, and the readability (distance) is also excellent. Therefore, they can be suitably used for applications such as photomask cases.

[0165] The polyamide elastomer (C) is also expected to have antistatic properties. For example, a disk (diameter 100 mm, thickness 2 mm) obtained by molding pellets of the thermoplastic resin composition of Example 23 was left for one day under conditions of a temperature of 23°C and a humidity of 50% RH, and then the surface resistivity (Ω) was measured at an applied voltage of 500 V, and was found to be 5×10 10 and showed good values.

[0166] Although the present invention has been described in detail using specific embodiments, it will be apparent to those skilled in the art that various modifications are possible within the scope of the invention. This application is based on Japanese Patent Application No. 2022-148261, filed on September 16, 2022, the entire contents of which are incorporated by reference.

Claims

1. a vinyl copolymer (A) obtained by copolymerizing a vinyl monomer mixture (ma) containing an aromatic vinyl monomer (a1) and a (meth)acrylic acid ester monomer (a2); a rubber-reinforced graft copolymer (B) obtained by graft copolymerizing a vinyl-based monomer mixture (mb) containing at least an aromatic vinyl-based monomer (b1), a (meth)acrylic acid ester-based monomer (b2), and a vinyl cyanide-based monomer (b3) in the presence of a rubber polymer (r); Polyamide elastomer (C) and A thermoplastic resin composition comprising: The vinyl copolymer (A) includes a vinyl copolymer (A1) obtained by copolymerizing a vinyl monomer mixture (ma1) containing an aromatic vinyl monomer (a1), a (meth)acrylic acid ester monomer (a2), and a vinyl cyanide monomer (a3), and has a weight average molecular weight of 50,000 to 300,000; per 100 parts by mass of the total of the vinyl copolymer (A), the rubber-reinforced graft copolymer (B), and the polyamide elastomer (C), a total of 60 to 92 parts by mass of a vinyl copolymer (A) and a rubber-reinforced graft copolymer (B); 8 to 40 parts by mass of polyamide elastomer (C) A thermoplastic resin composition comprising:

2. per 100 parts by mass of the total of the vinyl copolymer (A), the rubber-reinforced graft copolymer (B), and the polyamide elastomer (C), The thermoplastic resin composition according to claim 1, comprising 20 to 65 parts by mass of the vinyl copolymer (A), 5 to 72 parts by mass of the rubber-reinforced graft copolymer (B), and 8 to 30 parts by mass of the polyamide elastomer (C).

3. a vinyl copolymer (A) obtained by copolymerizing a vinyl monomer mixture (ma) containing an aromatic vinyl monomer (a1) and a (meth)acrylic acid ester monomer (a2); a rubber-reinforced graft copolymer (B) obtained by graft copolymerizing a vinyl-based monomer mixture (mb) containing at least an aromatic vinyl-based monomer (b1), a (meth)acrylic acid ester-based monomer (b2), and a vinyl cyanide-based monomer (b3) in the presence of a rubber polymer (r); Polyamide elastomer (C) and A thermoplastic resin composition comprising: The vinyl copolymer (A) includes a vinyl copolymer (A1) obtained by copolymerizing a vinyl monomer mixture (ma1) containing an aromatic vinyl monomer (a1), a (meth)acrylic acid ester monomer (a2), and a vinyl cyanide monomer (a3), and has a weight average molecular weight of 100,000 to 250,000; per 100 parts by mass of the total of the vinyl copolymer (A), the rubber-reinforced graft copolymer (B), and the polyamide elastomer (C), 20 to 40 parts by mass of a vinyl copolymer (A), 47 to 65 parts by mass of a rubber-reinforced graft copolymer (B), 8 to 13 parts by mass of polyamide elastomer (C), 35 parts by mass or less of a vinyl copolymer (A1) The thermoplastic resin composition according to claim 1, comprising:

4. the vinyl copolymer (A) further contains a vinyl copolymer (A2) obtained by copolymerizing a vinyl monomer mixture (ma2) containing an aromatic vinyl monomer (a1), a (meth)acrylic acid ester monomer (a2), and a maleimide monomer (a4), and having a weight average molecular weight of 100,000 to 250,000; 2. The thermoplastic resin composition according to claim 1, comprising 20 parts by mass or less of the vinyl copolymer (A2) per 100 parts by mass of the vinyl copolymer (A), the rubber-reinforced graft copolymer (B), and the polyamide elastomer (C) combined.

5. the refractive indexes of the vinyl copolymer (A), the acetone-soluble component of the rubber-reinforced graft copolymer (B), and the polyamide elastomer (C) are in the range of 1.505 to 1.520; 2. The thermoplastic resin composition according to claim 1, wherein the difference in refractive index between these components is 0.03 or less.

6. 2. The thermoplastic resin composition according to claim 1, wherein the content of the vinyl cyanide monomer component in 100% by mass of the acetone soluble matter of the thermoplastic resin composition is 0.5 to 10% by mass.

7. A molded article made from the thermoplastic resin composition according to any one of claims 1 to 6.

8. The molded article according to claim 7, which is a sheet-like molded article.

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