Vinyl-chloride-based resin composition and vinyl-chloride-based resin molded body

Abstract

Provided is a vinyl-chloride-based resin composition capable of enhancing both static thermal stability and dynamic thermal stability and enhancing the heat resistance of a resulting vinyl-chloride-based resin molded body.　A vinyl-chloride-based resin composition according to the present invention contains: a chlorinated vinyl-chloride-based resin; an aminouracil compound or an aminothiouracil compound; a perchloric-acid-carrying hydrotalcite compound or a perchlorate; and an alkaline earth metal hydroxide or an alkaline earth metal oxide. The ratio of the aminouracil compound content or the aminothiouracil compound content to the perchloric-acid-carrying hydrotalcite compound content is 3.5 or less, or the ratio of the aminouracil compound content or the aminothiouracil compound content to the perchlorate content is 30.0 or less.

Description

Vinyl chloride resin composition and vinyl chloride resin molded article

[0001] The present invention relates to a vinyl chloride resin composition and a vinyl chloride resin molded article using the vinyl chloride resin composition.

[0002] Vinyl chloride resins are processed into various molded articles such as joints, pipes, plates, containers, etc., and are used in many fields. Vinyl chloride resins are particularly suitable for use in pipes because of their excellent mechanical strength, weather resistance, heat resistance, and chemical resistance.

[0003] When vinyl chloride resins are used to produce molded articles, stable molding can be difficult because vinyl chloride resins have low thermal stability and are prone to thermal decomposition due to the elimination of hydrogen chloride during heat molding, which can result in reduced mechanical strength and discoloration of the resulting molded articles.

[0004] To enhance the thermal stability of vinyl chloride resins, heat stabilizers are sometimes used together with vinyl chloride resins. Known examples of such heat stabilizers include amino-based heat stabilizers, tin-based heat stabilizers, calcium-zinc-based heat stabilizers, barium-zinc-based heat stabilizers, and barium-cadmium-based heat stabilizers.

[0005] Patent Document 1 listed below discloses a stabilizer composition containing a substantially metal-free perchlorate, a first amine-containing stabilizer, and a second amine-containing stabilizer, wherein the first amine-containing stabilizer and the second amine-containing stabilizer are aminoalcohols, dihydropyridines, aminocrotonates, aminouracils, phenylindoles, or mixtures containing at least one of these, and the first amine-containing stabilizer and the second amine-containing stabilizer are different types of stabilizers.

[0006] Japanese Patent Application Laid-Open No. 2006-104474

[0007] Generally, known indicators of thermal stability include static thermal stability (gear oven heat resistance), which is an indicator of the thermal stability during the period in which a resin molded article formed from a resin composition is in use, and dynamic thermal stability (plast heat resistance), which is an indicator of the thermal stability of a resin composition during heat molding.

[0008] When a heat stabilizer such as that described in Patent Document 1 is used, a stabilizer containing perchlorate and an amine, which has the function of capturing hydrogen chloride, is used, so that decomposition of the vinyl chloride resin in the resulting vinyl chloride resin molded article can be suppressed and the static heat stability (heat stability of the vinyl chloride resin molded article during use) can be increased to a certain extent.

[0009] However, it is difficult to sufficiently enhance the dynamic thermal stability of vinyl chloride resin compositions (thermal stability of vinyl chloride resin compositions during heat molding) using conventional heat stabilizers. In particular, when a chlorinated vinyl chloride resin is used as the vinyl chloride resin, higher temperatures (e.g., 190°C to 220°C) are required during molding, which makes it easy for the chlorinated vinyl chloride resin to undergo thermal decomposition during heat molding, resulting in the problem of discoloration of the resulting resin molded article to black. In other words, it is difficult to enhance both static and dynamic thermal stability of resin compositions containing chlorinated vinyl chloride resins using conventional heat stabilizers.

[0010] Furthermore, resin compositions using conventional heat stabilizers have the problem that they are unable to sufficiently increase heat resistance and softening temperature.

[0011] An object of the present invention is to provide a vinyl chloride resin composition that can improve both static thermal stability and dynamic thermal stability and can improve the heat resistance of the resulting vinyl chloride resin molded article. Another object of the present invention is to provide a vinyl chloride resin molded article using the vinyl chloride resin composition.

[0012] This specification discloses the following vinyl chloride resin composition and vinyl chloride resin molded article.

[0013] Item 1. A vinyl chloride resin composition comprising a chlorinated vinyl chloride resin, an aminouracil compound or an aminothiouracil compound, a hydrotalcite compound or a perchlorate salt supporting perchloric acid, and an alkaline earth metal hydroxide or an alkaline earth metal oxide, and having the following structure A or structure B:

[0014] Configuration A: The vinyl chloride resin composition contains the hydrotalcite-based compound supporting perchloric acid, and the ratio of the content of the aminouracil compound or the aminothiouracil compound to the content of the hydrotalcite-based compound supporting perchloric acid is 3.5 or less.

[0015] Configuration B: The vinyl chloride resin composition contains the perchlorate, and the ratio of the content of the aminouracil compound or the aminothiouracil compound to the content of the perchlorate is 30.0 or less.

[0016] Item 2. The vinyl chloride resin composition according to Item 1, wherein the vinyl chloride resin composition contains the alkaline earth metal hydroxide, and the alkaline earth metal hydroxide contains magnesium hydroxide or calcium hydroxide.

[0017] Item 3. The vinyl chloride resin composition according to Item 1 or 2, wherein the ratio of the content of the aminouracil compound or the aminothiouracil compound to the content of the alkaline earth metal hydroxide or the alkaline earth metal oxide is 5.0 or less.

[0018] Item 4. The vinyl chloride resin composition according to any one of Items 1 to 3, wherein the chlorinated vinyl chloride resin has a chlorine content of 60% by weight or more.

[0019] Item 5. The vinyl chloride resin composition according to Item 4, wherein the chlorinated vinyl chloride resin has a chlorine content of 64% by weight or more.

[0020] Item 6. The vinyl chloride resin composition according to any one of Items 1 to 5, wherein the vinyl chloride resin composition contains an impact modifier, and the content of the impact modifier is 1 part by weight or more and 20 parts by weight or less per 100 parts by weight of the chlorinated vinyl chloride resin.

[0021] Item 7. A vinyl chloride resin molded article, which is a molded article of the vinyl chloride resin composition according to any one of Items 1 to 6.

[0022] The vinyl chloride resin composition according to the present invention comprises a chlorinated vinyl chloride resin, an aminouracil compound or an aminothiouracil compound, a hydrotalcite compound carrying perchloric acid or a perchlorate, and an alkaline earth metal hydroxide or an alkaline earth metal oxide. The vinyl chloride resin composition according to the present invention has specific structure A or specific structure B. Because the vinyl chloride resin composition according to the present invention has the above-mentioned structure, it is possible to improve both the static thermal stability and the dynamic thermal stability, and to improve the heat resistance of the resulting vinyl chloride resin molded article.

[0023] The present invention will be described in detail below.

[0024] (Vinyl chloride resin composition) The vinyl chloride resin composition according to the present invention comprises a chlorinated vinyl chloride resin, an aminouracil compound or an aminothiouracil compound, a hydrotalcite compound carrying perchloric acid or a perchlorate, and an alkaline earth metal hydroxide or an alkaline earth metal oxide. The vinyl chloride resin composition according to the present invention has the following structure A or the following structure B.

[0025] Configuration A: The vinyl chloride resin composition contains the hydrotalcite-based compound carrying perchloric acid, and the ratio of the content of the aminouracil compound or the aminothiouracil compound to the content of the hydrotalcite-based compound carrying perchloric acid is 3.5 or less.

[0026] Configuration B: The vinyl chloride resin composition contains the perchlorate, and the ratio of the content of the aminouracil compound or the aminothiouracil compound to the content of the perchlorate is 30.0 or less.

[0027] That is, the vinyl chloride resin composition according to the present invention contains the following components:

[0028] (A) Chlorinated vinyl chloride resin (B1) An aminouracil compound, or (B2) An aminothiouracil compound (C1) A hydrotalcite compound carrying perchloric acid, or (C2) A perchlorate (D1) An alkaline earth metal hydroxide, or (D2) An alkaline earth metal oxide

[0029] The vinyl chloride resin composition contains an aminouracil compound (B1) or an aminothiouracil compound (B2). The vinyl chloride resin composition may contain an aminouracil compound (B1), an aminothiouracil compound (B2), or both an aminouracil compound (B1) and an aminothiouracil compound (B2). The vinyl chloride resin composition may contain only one of an aminouracil compound (B1) and an aminothiouracil compound (B2). The vinyl chloride resin composition contains at least one component (B) selected from the group consisting of an aminouracil compound (B1) and an aminothiouracil compound (B2). The vinyl chloride resin composition contains component (B) as an essential component. The vinyl chloride resin composition may not contain an aminouracil compound (B1) or an aminothiouracil compound (B2). When the vinyl chloride resin composition contains an aminouracil compound (B1), the vinyl chloride resin composition optionally contains an aminothiouracil compound (B2).When the vinyl chloride resin composition contains an aminothiouracil compound (B2), the vinyl chloride resin composition optionally contains an aminouracil compound (B1).

[0030] The vinyl chloride resin composition contains (C1) a hydrotalcite-type compound supporting perchloric acid, or (C2) a perchlorate. The vinyl chloride resin composition may contain (C1) a hydrotalcite-type compound supporting perchloric acid, or (C2) a perchlorate, or may contain both (C1) a hydrotalcite-type compound supporting perchloric acid and (C2) a perchlorate. The vinyl chloride resin composition may contain only one of (C1) a hydrotalcite-type compound supporting perchloric acid and (C2) a perchlorate. The vinyl chloride resin composition contains at least one component (C) selected from the group consisting of (C1) a hydrotalcite-type compound supporting perchloric acid and (C2) a perchlorate. The vinyl chloride resin composition contains component (C) as an essential component. The vinyl chloride resin composition may not contain (C1) a hydrotalcite-type compound supporting perchloric acid, and may not contain (C2) a perchlorate. When the vinyl chloride resin composition contains (C1) a hydrotalcite-type compound supporting perchloric acid, the vinyl chloride resin composition optionally contains (C2) a perchlorate. When the vinyl chloride resin composition contains (C2) a perchlorate, the vinyl chloride resin composition optionally contains (C1) a hydrotalcite-type compound supporting perchloric acid.

[0031] The vinyl chloride resin composition contains (D1) an alkaline earth metal hydroxide or (D2) an alkaline earth metal oxide. The vinyl chloride resin composition may contain (D1) an alkaline earth metal hydroxide, (D2) an alkaline earth metal oxide, or both (D1) an alkaline earth metal hydroxide and (D2) an alkaline earth metal oxide. The vinyl chloride resin composition may contain only one of (D1) an alkaline earth metal hydroxide and (D2) an alkaline earth metal oxide. The vinyl chloride resin composition contains at least one component (D) selected from the group consisting of (D1) an alkaline earth metal hydroxide and (D2) an alkaline earth metal oxide. The vinyl chloride resin composition contains component (D) as an essential component. The vinyl chloride resin composition may not contain (D1) an alkaline earth metal hydroxide or may not contain (D2) an alkaline earth metal oxide. When the vinyl chloride resin composition contains (D1) an alkaline earth metal hydroxide, the vinyl chloride resin composition optionally contains (D2) an alkaline earth metal oxide. When the vinyl chloride resin composition contains (D2) an alkaline earth metal oxide, the vinyl chloride resin composition optionally contains (D1) an alkaline earth metal hydroxide.

[0032] In conventional vinyl chloride resin compositions, when the resin composition contains a chlorinated vinyl chloride resin, it is difficult to improve both the static thermal stability and the dynamic thermal stability.

[0033] Furthermore, resin compositions using conventional heat stabilizers have the problem that they are unable to sufficiently increase heat resistance and softening temperature.

[0034] On the other hand, the vinyl chloride resin composition according to the present invention has the above-mentioned features, and therefore can improve static thermal stability (thermal stability of vinyl chloride resin molded articles during use). Furthermore, the vinyl chloride resin composition according to the present invention has the above-mentioned features, and therefore can improve dynamic thermal stability (thermal stability of vinyl chloride resin compositions during heat molding), despite the inclusion of a chlorinated vinyl chloride resin. That is, the vinyl chloride resin composition according to the present invention has the above-mentioned features, and therefore can improve both static and dynamic thermal stability. As a result, discoloration of the resulting vinyl chloride resin molded articles can be prevented (the occurrence of poor appearance can be prevented).

[0035] Furthermore, since the vinyl chloride resin composition according to the present invention has the above-mentioned features, it is possible to improve the heat resistance of the vinyl chloride resin molded article obtained.Since the vinyl chloride resin composition according to the present invention has the above-mentioned features, it is possible to increase the Vicat softening temperature of the vinyl chloride resin molded article obtained.

[0036] Since the static thermal stability, dynamic thermal stability, and heat resistance can be improved, the vinyl chloride resin composition of the present invention is preferably used to obtain a vinyl chloride resin molded article. A vinyl chloride resin molded article can be obtained using the vinyl chloride resin composition of the present invention. Since the static thermal stability, dynamic thermal stability, and heat resistance can be improved, the vinyl chloride resin composition of the present invention is preferably used to obtain a vinyl chloride resin pipe. A vinyl chloride resin pipe can be obtained using the vinyl chloride resin composition of the present invention.

[0037] Hereinafter, each component contained in the vinyl chloride resin composition will be described.

[0038] <(A) Chlorinated vinyl chloride resin> The vinyl chloride resin composition contains (A) a chlorinated vinyl chloride resin. The chlorinated vinyl chloride resin is a resin obtained by chlorinating a vinyl chloride resin.

[0039] As the vinyl chloride resin, conventionally known vinyl chloride resins can be used. Examples of the vinyl chloride resin include (1) a homopolymer of a vinyl chloride monomer, (2) a copolymer of a vinyl chloride monomer and a monomer having an unsaturated bond copolymerizable with the vinyl chloride monomer, and (3) a graft polymer in which vinyl chloride is graft-polymerized onto a polymer or copolymer other than vinyl chloride. The vinyl chloride resins may be used alone or in combination of two or more.

[0040] Examples of monomers having an unsaturated bond copolymerizable with the vinyl chloride monomer include α-olefin compounds such as ethylene, propylene, and butylene; vinyl ester compounds such as vinyl acetate and vinyl propionate; vinyl ether compounds such as butyl vinyl ether and cetyl vinyl ether; alkyl (meth)acrylate compounds such as methyl (meth)acrylate, ethyl (meth)acrylate, and butyl (meth)acrylate; cyano group-containing compounds such as acrylonitrile; carboxyl group-containing compounds such as itaconic acid, maleic acid, and fumaric acid, aryl (meth)acrylate compounds such as phenyl (meth)acrylate; aromatic vinyl compounds such as styrene and α-methylstyrene; dicarboxylic acid compounds such as maleic anhydride; halogenated vinyl compounds such as vinylidene chloride and vinylidene fluoride; and N-substituted maleimide compounds such as N-phenylmaleimide and N-cyclohexylmaleimide. The monomers having an unsaturated bond copolymerizable with the vinyl chloride monomer may be used alone or in combination of two or more.

[0041] The copolymer of the vinyl chloride monomer and the monomer having an unsaturated bond copolymerizable with the vinyl chloride monomer may be a random copolymer, a block copolymer, or a graft copolymer.

[0042] Examples of the polymers and copolymers other than vinyl chloride include copolymers of an α-olefin compound and a vinyl ester compound, such as ethylene-vinyl acetate copolymer; copolymers of an α-olefin compound, a vinyl ester compound, and carbon monoxide, such as ethylene-vinyl acetate-carbon monoxide copolymer; copolymers of an α-olefin compound and an alkyl (meth)acrylate compound, such as ethylene-methyl methacrylate copolymer and ethylene-ethyl acrylate copolymer; and copolymers of an α-olefin compound, an alkyl (meth)acrylate compound, and carbon monoxide, such as ethylene-butyl acrylate-carbon monoxide copolymer; copolymers of two or more different α-olefin compounds, such as ethylene-propylene copolymer; copolymers of unsaturated nitrile compounds and diene compounds, such as acrylonitrile-butadiene copolymer; polyurethane; and chlorinated polyolefin compounds, such as chlorinated polyethylene and chlorinated polypropylene. The polymers and copolymers other than vinyl chloride may be used alone, or two or more may be used in combination.

[0043] The polymerization method of the vinyl chloride monomer and the polymerization method of the vinyl chloride monomer and the monomer having an unsaturated bond copolymerizable with the vinyl chloride monomer are not particularly limited. Examples of the polymerization method include suspension polymerization, emulsion polymerization, solution polymerization, bulk polymerization, and precipitation polymerization. From the viewpoint of efficiently obtaining a vinyl chloride resin, the polymerization method is preferably suspension polymerization, emulsion polymerization, solution polymerization, or precipitation polymerization.

[0044] The chlorinated vinyl chloride resin is preferably obtained by polymerizing the vinyl chloride monomer or the vinyl chloride monomer with a monomer having an unsaturated bond copolymerizable with the vinyl chloride monomer to obtain a vinyl chloride resin, and then chlorinating the vinyl chloride resin.The chlorinated vinyl chloride resin is preferably obtained by chlorinating a vinyl chloride resin that is a polymer of the vinyl chloride monomer or the vinyl chloride monomer and a monomer having an unsaturated bond copolymerizable with the vinyl chloride monomer.

[0045] The method for chlorinating the vinyl chloride resin is not particularly limited. Examples of the method for chlorinating the vinyl chloride resin include a method in which the vinyl chloride resin is placed in an aqueous solvent to obtain a suspension, and then chlorine is added to react the vinyl chloride resin with chlorine. This chlorination reaction proceeds under heating conditions or light irradiation conditions.

[0046] From the viewpoint of enhancing the thermal stability of the resulting chlorinated vinyl chloride resin and vinyl chloride resin composition, the chlorination reaction is preferably carried out under heating conditions.

[0047] From the viewpoint of increasing the efficiency of the chlorination reaction, the temperature during the heating is preferably 80°C or higher and preferably 140°C or lower.

[0048] The chlorinated vinyl chloride resin preferably has, in its molecular structure, structural units represented by the following formulas (a), (b), and (c) (structural unit (a), structural unit (b), and structural unit (c)).

[0049] -CCl ２ - (a) -CHCl- (b) -CH ２ - (c)

[0050] The contents (mol %) of the structural units (a), (b), and (c) in the chlorinated vinyl chloride resin are indicators reflecting the number of sites into which chlorine is introduced when the vinyl chloride resin is chlorinated. In the vinyl chloride resin before chlorination, the content of the structural unit (a) is preferably 0 mol %, the content of the structural unit (b) is 50.0 mol %, and the content of the structural unit (c) is 50.0 mol %, based on a total of 100 mol % of the structural units (a), (b), and (c). When the vinyl chloride resin is chlorinated, the content of the structural unit (c) decreases and the contents of the structural units (a) and (b) increase. In this case, if the content of the structural unit (a), which is unstable due to significant steric hindrance, becomes too large, or if there is an imbalance between chlorinated and unchlorinated sites within the same molecule of the chlorinated vinyl chloride resin, the non-uniformity of the chlorination state increases. When this non-uniformity is reduced (when uniformity is increased), the thermal stability (static thermal stability and dynamic thermal stability) of the chlorinated vinyl chloride resin and vinyl chloride resin composition can be further improved.

[0051] In the chlorinated vinyl chloride resin, the content of the structural unit (a) is preferably 2.0 mol% or more, preferably 17.5 mol% or less, and more preferably 16.0 mol% or less, based on a total of 100 mol% of the structural units (a), (b), and (c). In the chlorinated vinyl chloride resin, the content of the structural unit (b) is preferably 46.0 mol% or more, more preferably 58.0 mol% or more, even more preferably 63.5 mol% or more, and preferably 70.0 mol% or less, based on a total of 100 mol% of the structural units (a), (b), and (c). In the chlorinated vinyl chloride resin, the content of the structural unit (c) is preferably 1.0 mol% or more, preferably 37.0 mol% or less, more preferably 35.8 mol% or less, and even more preferably 30.5 mol% or less. When the contents of the structural units (a), (b), and (c) in the chlorinated vinyl chloride resin are equal to or greater than the above-mentioned lower limit and equal to or less than the above-mentioned upper limit, the uniformity of the chlorination state of the chlorinated vinyl chloride resin can be increased, thereby further improving the static thermal stability and dynamic thermal stability of the vinyl chloride resin composition and improving the moldability of the vinyl chloride resin composition.

[0052] From the viewpoint of further enhancing the static thermal stability and dynamic thermal stability of the vinyl chloride resin composition, it is particularly preferred that, relative to the total of 100 mol% of the structural units (a), (b), and (c) in the chlorinated vinyl chloride resin, the content of the structural unit (b) is 58.0 mol% or more and the content of the structural unit (c) is 35.8 mol% or less.

[0053] The contents of the structural units (a), (b), and (c) in the chlorinated vinyl chloride resin can be measured by molecular structure analysis using NMR. NMR analysis can be performed in accordance with the method described in R. A. Komoroski, R. G. Parker, and J. P. Shocker, Macromolecules, 1985, 18, 1257-1265.

[0054] The chlorinated vinyl chloride resin may or may not have a structural unit (structural unit (d)) represented by the following formula (d) in its molecular structure. The structural unit (d) is a portion of the repeating unit in the vinyl chloride resin that is not chlorinated. In this specification, the structural unit (d) may be referred to as a VC unit.

[0055] -CH ２ -CHCl- (d)

[0056] The VC units present in the chlorinated vinyl chloride resin serve as the starting point for the hydrogen chloride elimination reaction during heat molding of the vinyl chloride resin composition, and continuous VC units facilitate the occurrence of continuous hydrogen chloride elimination reactions (zipper reactions). In particular, the smaller the amount of VC units with tetrads or more, the less likely the hydrogen chloride elimination reaction will occur, further improving the thermal stability of the chlorinated vinyl chloride resin and vinyl chloride resin composition. Note that VC units with tetrads or more refer to a moiety in which four or more VC units are bonded in succession.

[0057] From the viewpoint of further suppressing a decrease in the thermal stability (particularly, dynamic thermal stability) of the vinyl chloride resin composition, the content of the tetrad or larger VC units in 100 mol% of the molecular weight of the chlorinated vinyl chloride resin is preferably 30.0 mol% or less, more preferably 28.0 mol% or less, and even more preferably 18.0 mol% or less. The lower limit of the content of the tetrad or larger VC units in 100 mol% of the molecular weight of the chlorinated vinyl chloride resin is not particularly limited. The content of the tetrad or larger VC units in 100 mol% of the molecular weight of the chlorinated vinyl chloride resin may be 0 mol% or more, may exceed 0 mol%, may be 1.0 mol% or more, or may be 5.0 mol% or more. The range of the content of the tetrad or larger VC units in 100 mol% of the molecular weight of the chlorinated vinyl chloride resin can be set by appropriately selecting the lower limit and the upper limit.

[0058] The content of the VC units having tetrads or more in 100 mol% of the molecular weight of the chlorinated vinyl chloride resin can be measured by molecular structure analysis using NMR. The NMR analysis can be performed in accordance with the method described in R. A. Komoroski, R. G. Parker, J. P. Shocker, Macromolecules, 1985, 18, 1257-1265.

[0059] The chlorinated vinyl chloride resin contained in the vinyl chloride resin composition is preferably in the form of particles. The volume average particle diameter of the chlorinated vinyl chloride resin is preferably 0.1 μm or more and preferably 500 μm or less. When the volume average particle diameter is equal to or greater than the lower limit, the handleability of the vinyl chloride resin composition can be improved. When the volume average particle diameter is equal to or less than the upper limit, the moldability of the vinyl chloride resin composition can be improved.

[0060] The volume-average particle size of the chlorinated vinyl chloride resin is the average particle size measured on a volume basis, and is the median diameter (D50) at 50%. The volume-average particle size can be measured by a laser diffraction / scattering method or the like.

[0061] The average degree of polymerization of the chlorinated vinyl chloride resin is preferably 500 or more, more preferably 600 or more, even more preferably 700 or more, and preferably 2000 or less, more preferably 1200 or less, even more preferably 1000 or less, and particularly preferably 800 or less. When the average degree of polymerization of the chlorinated vinyl chloride resin is at least the above-mentioned lower limit, the mechanical strength and impact resistance of the obtained vinyl chloride resin molded article can be increased, and long-term performance such as fatigue properties can be made less likely to be impaired. When the average degree of polymerization of the chlorinated vinyl chloride resin is at most the above-mentioned upper limit, the fluidity of the vinyl chloride resin composition can be increased, and moldability can be improved.

[0062] The average degree of polymerization of the chlorinated vinyl chloride resin can be measured, for example, as follows. The chlorinated vinyl chloride resin is dissolved in tetrahydrofuran (THF), and then insoluble components are removed by filtration. The THF in the filtrate is dried and removed to obtain a measurement sample. The average degree of polymerization of the measurement sample measured in accordance with JIS K6721 "Testing Methods for Vinyl Chloride Resins" is taken as the average degree of polymerization of the chlorinated vinyl chloride resin.

[0063] The chlorine content of the chlorinated vinyl chloride resin is preferably 60% by weight or more, more preferably 63% by weight or more, even more preferably 64% by weight or more, particularly preferably 65% ​​by weight or more, and is preferably 72% by weight or less, more preferably 69% by weight or less, and even more preferably 67.5% by weight or less. When the chlorine content of the chlorinated vinyl chloride resin is equal to or greater than the lower limit, the heat resistance of the resulting vinyl chloride resin molded article can be further improved. When the chlorine content of the chlorinated vinyl chloride resin is equal to or less than the upper limit, the moldability of the vinyl chloride resin composition can be improved, and the impact resistance and surface smoothness of the resulting vinyl chloride resin molded article can be improved.

[0064] The chlorine content of the chlorinated vinyl chloride resin can be determined by potentiometric titration in accordance with JIS K7229.

[0065] In ultraviolet-visible spectroscopic measurement (UV-Vis), the absorbance of the chlorinated vinyl chloride resin at a wavelength of 216 nm is preferably 8.0 or less, more preferably 4.0 or less, even more preferably 1.0 or less, and particularly preferably 0.8 or less. When the absorbance of the chlorinated vinyl chloride resin at a wavelength of 216 nm is equal to or less than the above upper limit, the influence of heterogeneous structures in the chlorinated vinyl chloride resin can be suppressed, and the thermal stability (particularly, dynamic thermal stability) of the vinyl chloride resin composition can be further improved. There is no particular limitation on the lower limit of the absorbance of the chlorinated vinyl chloride resin at a wavelength of 216 nm. The absorbance of the chlorinated vinyl chloride resin at a wavelength of 216 nm may be 0.01 or more, or may be 0.1 or more.

[0066] In an ultraviolet absorption spectrum, ultraviolet light with a wavelength of 216 nm is the wavelength at which the heterogeneous structures (-CH=CH-C(=O)- and -CH=CH-CH=CH-) in the chlorinated vinyl chloride resin exhibit absorption. The absorbance of the chlorinated vinyl chloride resin in ultraviolet-visible spectroscopy (UV-Vis) can be used to quantify the heterogeneous structures in the molecular chain during the chlorination reaction of the vinyl chloride resin, and this can be used as an index of the thermal stability of the chlorinated vinyl chloride resin. In the molecular structure of the chlorinated vinyl chloride resin, the chlorine atom bonded to the carbon adjacent to the double-bonded carbon is unstable, and a hydrogen chloride elimination reaction occurs from this chlorine atom during heat molding of the vinyl chloride resin composition. That is, the smaller the absorbance at a wavelength of 216 nm in ultraviolet-visible spectroscopy (UV-Vis), the less likely the hydrogen chloride elimination reaction occurs during heat molding of the vinyl chloride resin composition, and the thermal stability (particularly, dynamic thermal stability) of the vinyl chloride resin composition tends to be further improved.

[0067] The absorbance of the chlorinated vinyl chloride resin at a wavelength of 216 nm can be measured, for example, by the following method. 10 mg of the chlorinated vinyl chloride resin is dissolved in 25 ml of tetrahydrofuran (THF) to obtain a sample. The absorbance of the obtained sample at a wavelength of 216 nm is measured using a spectrophotometer (Hitachi, Ltd., "U-3500").

[0068] In particular, when the chlorine content of the chlorinated vinyl chloride resin is 63% by weight or more and 69% by weight or less (or 64% by weight or more and 69% by weight or less), the absorbance of the chlorinated vinyl chloride resin at a wavelength of 216 nm is preferably 0.8 or less. Furthermore, when the chlorine content of the chlorinated vinyl chloride resin is more than 69% by weight and 72% by weight or less, the absorbance of the chlorinated vinyl chloride resin at a wavelength of 216 nm is preferably 8.0 or less. In these cases, the influence of heterogeneous structures in the chlorinated vinyl chloride resin can be suppressed, and as a result, deterioration in the thermal stability (particularly, dynamic thermal stability) of the vinyl chloride resin composition can be further suppressed.

[0069] From the viewpoint of suppressing a decrease in the thermal stability (particularly, dynamic thermal stability) of the vinyl chloride resin composition, the time required for the total amount of hydrogen chloride desorption from the chlorinated vinyl chloride resin at 190°C to reach 7000 ppm (hydrogen chloride desorption time) is preferably 60 seconds or more, more preferably 70 seconds or more, even more preferably 80 seconds or more, and particularly preferably 100 seconds or more. The upper limit of the hydrogen chloride desorption time is not particularly limited. From the viewpoint of suppressing a decrease in the thermal stability (particularly, dynamic thermal stability) of the vinyl chloride resin composition, the longer the hydrogen chloride desorption time, the better.

[0070] The chlorinated vinyl chloride resin undergoes thermal decomposition at high temperatures, generating HCl gas. Generally, as the degree of chlorination of a chlorinated vinyl chloride resin increases, the number of VC units decreases, resulting in a decrease in the amount of hydrogen chloride released. However, as the degree of chlorination of a chlorinated vinyl chloride resin increases, the amount of non-uniform chlorination and heterogeneous structures increases, and thermal stability tends to decrease. Therefore, by measuring the amount of hydrogen chloride released, the increase in non-uniform chlorination and heterogeneous structures can be analyzed. For example, the hydrogen chloride release time can be used as an indicator of the thermal stability of a chlorinated vinyl chloride resin and a vinyl chloride resin composition.

[0071] In particular, when the chlorine content of the chlorinated vinyl chloride resin is 63% by weight or more and 69% by weight or less (or 64% by weight or more and 69% by weight or less), the hydrogen chloride elimination time is preferably 60 seconds or more, more preferably 70 seconds or more, and even more preferably 80 seconds or more. Furthermore, when the chlorine content of the chlorinated vinyl chloride resin is more than 69% by weight but not more than 72% by weight, the hydrogen chloride elimination time is preferably 100 seconds or more, more preferably 120 seconds or more, and even more preferably 140 seconds or more. In these cases, the thermal stability (particularly the dynamic thermal stability) of the vinyl chloride resin composition can be further improved.

[0072] The hydrogen chloride desorption time can be measured as follows. First, 1 g of chlorinated polyvinyl chloride resin is placed in a test tube and heated to 190°C using an oil bath, and the generated HCl gas is collected. The collected HCl gas is dissolved in 100 ml of ion-exchanged water, and the pH is measured. Based on the measured pH value, the HCl concentration (ppm) (how many grams of HCl are generated per 1 million grams of chlorinated polyvinyl chloride resin) is calculated. The time required for the HCl concentration to reach 7,000 ppm is measured.

[0073]

[0033] The content of the chlorinated vinyl chloride resin in 100% by weight of the vinyl chloride resin composition is preferably 65% ​​by weight or more, more preferably 70% by weight or more, and preferably 99% by weight or less, more preferably 95% by weight or less, and even more preferably 93% by weight or less. When the content of the chlorinated vinyl chloride resin is equal to or greater than the lower limit, the mechanical strength and impact resistance of the resulting vinyl chloride resin molded article can be increased. When the content of the chlorinated vinyl chloride resin is equal to or less than the upper limit, the fluidity of the vinyl chloride resin composition can be increased, resulting in good moldability.

[0074] <(B1) Aminouracil Compound and (B2) Aminothiouracil Compound> The vinyl chloride resin composition contains (B1) an aminouracil compound or (B2) an aminothiouracil compound.

[0075] From the viewpoint of more effectively exerting the effects of the present invention, particularly from the viewpoint of further enhancing the thermal stability of the vinyl chloride resin composition, the (B1) aminouracil compound or the (B2) aminothiouracil compound is preferably a compound having a structure represented by the following formula (1) or formula (2), and more preferably a compound having a structure represented by the following formula (1). The (B1) aminouracil compound is preferably a compound having a structure represented by the following formula (1), in which X in the following formula (1) represents an oxygen atom. The (B2) aminothiouracil compound is preferably a compound having a structure represented by the following formula (1), in which X in the following formula (1) represents a sulfur atom, or a compound having a structure represented by the following formula (2). The (B2) aminothiouracil compound is more preferably a compound having a structure represented by the following formula (1), in which X in the following formula (1) represents a sulfur atom.

[0076]

[0077] In the above formula (1), R1 and R2 represent an alkyl group, an alkenyl group, a cycloalkyl group, a phenylalkyl group, or a hydrogen atom. In the above formula (1), X represents a sulfur atom or an oxygen atom. In the above formula (1), R1 and R2 may have a substituent. In the above formula (1), R1 and R2 may be the same or different.

[0078]

[0079] In the above formula (2), R1 and R2 represent an alkyl group, an alkenyl group, a cycloalkyl group, a phenylalkyl group, or a hydrogen atom. In the above formula (2), R1 and R2 may have a substituent. In the above formula (2), R1 and R2 may be the same or different.

[0080] In the above formula (1) or (2), R1 and R2 are more preferably an alkyl group having 1 to 12 carbon atoms, an alkenyl group having 1 to 12 carbon atoms, a cycloalkyl group having 1 to 12 carbon atoms, a phenylalkyl group having 1 to 12 carbon atoms, or a hydrogen atom. The number of carbon atoms in the alkyl group, alkenyl group, cycloalkyl group, or phenylalkyl group is preferably 1 to 12, more preferably 1 to 8. In these cases, the compatibility of the compound having the structure represented by the above formula (1) or (2) with the chlorinated vinyl chloride resin can be improved, and the thermal stability of the vinyl chloride resin composition can be further improved.

[0081] From the viewpoint of improving the compatibility of the compound having the structure represented by the above formula (1) or (2) with the chlorinated vinyl chloride resin and further increasing the thermal stability of the vinyl chloride resin composition, it is preferable that R1 and R2 in the above formula (1) or (2) are an alkyl group having 1 to 4 carbon atoms, an alkenyl group having 1 to 4 carbon atoms, or a cycloalkyl group having 1 to 4 carbon atoms.

[0082] From the viewpoint of increasing the compatibility between the compound having the structure represented by the above formula (1) or (2) and the chlorinated vinyl chloride resin, and further increasing the thermal stability of the vinyl chloride resin composition, R1 and R2 in the above formula (1) or (2) are preferably alkyl groups, more preferably alkyl groups having 1 to 12 carbon atoms, and even more preferably alkyl groups having 1 to 4 carbon atoms.

[0083] In the above formula (1) or (2), when R1 and R2 are alkyl groups, alkenyl groups, or phenylalkyl groups and have a substituent on the alkyl group moiety in R1 and R2, examples of the substituent include an alkoxy group having 1 to 20 carbon atoms, a cycloalkyl group having 1 to 20 carbon atoms, a hydroxy group, and a halogen atom. In the above formula (1) or (2), when R1 and R2 are phenylalkyl groups and have a substituent on the phenyl group moiety, examples of the substituent include an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a cycloalkyl group having 1 to 20 carbon atoms, a hydroxy group, and a halogen atom.

[0084] Examples of the (B1) aminouracil compound or (B2) aminothiouracil compound having a structure represented by the above formula (1) or (2) include 6-amino-1,3-dialkyluracil, 6-amino-1,3-dialkylthiouracil, 6-aminouracil, and 6-aminothiouracil. The alkyl group in the 6-amino-1,3-dialkyluracil and 6-amino-1,3-dialkylthiouracil may be linear or branched. The alkyl group is preferably an alkyl group having 1 to 12 carbon atoms, and more preferably an alkyl group having 1 to 8 carbon atoms. Examples of the alkyl group having 1 to 8 carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group. The alkyl group is particularly preferably an alkyl group having 1 to 4 carbon atoms. The two alkyl groups in the 6-amino-1,3-dialkyluracil and the 6-amino-1,3-dialkylthiouracil may be the same or different.

[0085] Examples of the (B1) aminouracil compound include 6-amino-1,3-dimethyluracil, 6-amino-1,3-dimyristyluracil, 6-amino-1,3-dipalmityluracil, 6-amino-1,3-distearyluracil, and 6-aminouracil. The (B1) aminouracil compound may be used alone or in combination of two or more.

[0086] Examples of the (B2) aminothiouracil compound include 6-amino-1,3-dimethylthiouracil, 6-amino-1,3-dimyristylthiouracil, 6-amino-1,3-dipalmitylthiouracil, 6-amino-1,3-distearylthiouracil, and 6-aminothiouracil. The (B2) aminothiouracil compound may be used alone or in combination of two or more.

[0087] The vinyl chloride resin composition more preferably contains 6-amino-1,3-dialkyluracil, 6-amino-1,3-dialkylthiouracil, 6-aminouracil, or 6-aminothiouracil, and even more preferably contains 6-amino-1,3-dimethyluracil, 6-amino-1,3-dimethylthiouracil, 6-aminouracil, or 6-aminothiouracil. The vinyl chloride resin composition more preferably contains 6-amino-1,3-dialkyluracil or 6-amino-1,3-dialkylthiouracil, and even more preferably contains 6-amino-1,3-dimethyluracil or 6-amino-1,3-dimethylthiouracil. In these cases, the thermal stability of the vinyl chloride resin composition can be further enhanced, and discoloration of the resulting vinyl chloride resin molded article can be prevented.

[0088] From the viewpoint of further enhancing the thermal stability of the vinyl chloride resin composition and preventing discoloration of the resulting vinyl chloride resin molded article, the vinyl chloride resin composition preferably contains an aminouracil compound (B1). From the viewpoint of further enhancing the thermal stability of the vinyl chloride resin composition and preventing discoloration of the resulting vinyl chloride resin molded article, the vinyl chloride resin composition more preferably contains 6-amino-1,3-dialkyluracil or 6-aminouracil, and even more preferably contains 6-amino-1,3-dimethyluracil or 6-aminouracil. From the viewpoint of further enhancing the thermal stability of the vinyl chloride resin composition and preventing discoloration of the resulting vinyl chloride resin molded article, the vinyl chloride resin composition more preferably contains 6-amino-1,3-dialkyluracil, and even more preferably contains 6-amino-1,3-dimethyluracil.

[0089] The content of the (B1) aminouracil compound or (B2) aminothiouracil compound is preferably 0.1 wt% or more, more preferably 0.3 wt% or more, even more preferably 0.5 wt% or more, and preferably 10.0 wt% or less, more preferably 5.0 wt% or less, even more preferably 3.0 wt% or less, and particularly preferably 2.0 wt% or less, based on 100 wt% of the vinyl chloride resin composition. When the (B1) aminouracil compound is contained in the vinyl chloride resin composition, the content of the (B1) aminouracil compound is preferably 0.1 wt% or more, more preferably 0.3 wt% or more, even more preferably 0.5 wt% or more, and preferably 10.0 wt% or less, more preferably 5.0 wt% or less, even more preferably 3.0 wt% or less, and particularly preferably 2.0 wt% or less, based on 100 wt% of the vinyl chloride resin composition. When the vinyl chloride resin composition contains the aminothiouracil compound (B2), the content of the aminothiouracil compound (B2) is preferably 0.1 wt% or more, more preferably 0.3 wt% or more, even more preferably 0.5 wt% or more, and preferably 10.0 wt% or less, more preferably 5.0 wt% or less, even more preferably 3.0 wt% or less, and particularly preferably 2.0 wt% or less, based on 100 wt% of the vinyl chloride resin composition. When the content of the aminouracil compound (B1) or the aminothiouracil compound (B2) is equal to or greater than the above-mentioned lower limit, the thermal stability (particularly the static thermal stability) of the vinyl chloride resin composition can be further improved. When the content of the aminouracil compound (B1) or the aminothiouracil compound (B2) is equal to or less than the above-mentioned upper limit, discoloration of the resulting vinyl chloride resin molded article can be prevented. In addition, when the vinyl chloride resin composition contains the aminouracil compound (B1) and the aminothiouracil compound (B2), the content of the aminouracil compound (B1) or the aminothiouracil compound (B2) indicates the total content of the aminouracil compound (B1) and the aminothiouracil compound (B2) (the same applies hereinafter).

[0090] The content of the aminouracil compound (B1) or the aminothiouracil compound (B2) relative to 100 parts by weight of the chlorinated vinyl chloride resin is preferably 0.1 part by weight or more, more preferably 0.3 part by weight or more, even more preferably 0.5 part by weight or more, and preferably 10.0 parts by weight or less, more preferably 5.0 parts by weight or less, even more preferably 3.0 parts by weight or less, and particularly preferably 2.0 parts by weight or less. When the vinyl chloride resin composition contains the aminouracil compound (B1), the content of the aminouracil compound (B1) relative to 100 parts by weight of the chlorinated vinyl chloride resin is preferably 0.1 part by weight or more, more preferably 0.3 part by weight or more, even more preferably 0.5 part by weight or more, and preferably 10.0 parts by weight or less, more preferably 5.0 parts by weight or less, even more preferably 3.0 parts by weight or less, and particularly preferably 2.0 parts by weight or less. When the vinyl chloride resin composition contains the aminothiouracil compound (B2), the content of the aminothiouracil compound (B2) is preferably 0.1 parts by weight or more, more preferably 0.3 parts by weight or more, even more preferably 0.5 parts by weight or more, and preferably 10.0 parts by weight or less, more preferably 5.0 parts by weight or less, even more preferably 3.0 parts by weight or less, and particularly preferably 2.0 parts by weight or less, per 100 parts by weight of the chlorinated vinyl chloride resin. When the content of the aminouracil compound (B1) or the aminothiouracil compound (B2) is equal to or greater than the above-mentioned lower limit, the thermal stability (particularly the static thermal stability) of the vinyl chloride resin composition can be further improved. When the content of the aminouracil compound (B1) or the aminothiouracil compound (B2) is equal to or less than the above-mentioned upper limit, discoloration of the resulting vinyl chloride resin molded article can be prevented.

[0091] <(C1) Hydrotalcite-Based Compound Supporting Perchloric Acid and (C2) Perchlorate> The vinyl chloride resin composition contains (C1) a hydrotalcite-based compound supporting perchloric acid or (C2) a perchlorate.

[0092] (C1) A hydrotalcite-based compound carrying perchloric acid (perchloric acid-supported hydrotalcite-based compound) is a compound in which perchloric acid is physically or chemically supported on hydrotalcite particles. In the (C1) hydrotalcite-based compound carrying perchloric acid, the structure of the hydrotalcite is preferably modified by perchloric acid. The (C1) hydrotalcite-based compound carrying perchloric acid is preferably a structurally modified product of hydrotalcites with perchloric acid.

[0093] (C1) The hydrotalcite-based compound supporting perchloric acid preferably contains perchlorate ions.

[0094] From the viewpoint of further improving the thermal stability, particularly the dynamic thermal stability, during hot molding, the hydrotalcite-type compound (C1) supporting perchloric acid preferably contains magnesium and aluminum, and more preferably contains magnesium, zinc, and aluminum. From the viewpoint of further improving the dynamic thermal stability and further improving the heat resistance of the resulting vinyl chloride resin molded article, the hydrotalcite-type compound (C1) supporting perchloric acid is preferably a compound represented by the following formula (11). Only one type of the hydrotalcite-type compound (C1) supporting perchloric acid may be used, or two or more types may be used in combination.

[0095] {(Mg) ｘ (Zn) ｙ} (Al) ｚ (OH) ２ (A ｎ－ ) ｘ / n・mH ２ O... (11)

[0096] In the above formula (11), A ｎ－ represents an n-valent interlayer anion. In the above formula (11), x, y, and z satisfy 0<x<1, 0≦y<1, 0.2≦z≦0.4, and x+y+z=1, and also satisfy (x+y) / z≦2.2. In the above formula (11), n ​​represents an integer of 1 to 4, and m represents an integer of 0 or more.

[0097] In the above formula (11), A ｎ－ As the hydroxide ion (OH －), carbonate ions (CO ３ ２－ ), sulfate ions (SO ４ ２－ ), and perchlorate ion (ClO ４ － In the above formula (11), A ｎ－ may be one kind or two or more kinds.

[0098] From the viewpoint of further increasing the thermal stability (particularly, dynamic thermal stability) of the vinyl chloride resin composition and further increasing the heat resistance of the resulting vinyl chloride resin molded article, it is preferable that A ｎ－ is the perchlorate ion (ClO ４ － ) is preferred.

[0099] The (C1) hydrotalcite-type compound supporting perchloric acid may be a commercially available product. Examples of the (C1) hydrotalcite-type compound supporting perchloric acid include Alkamiser 5 (manufactured by Kyowa Chemical Industry Co., Ltd.).

[0100] The (C1) hydrotalcite-type compound carrying perchloric acid may be a natural product or a synthetic product. The (C1) hydrotalcite-type compound carrying perchloric acid may have its surface coated with a coating agent. Examples of the coating agent include higher fatty acids such as stearic acid, higher fatty acid metal salts such as alkali metal oleates, organic sulfonic acid metal salts such as alkali metal dodecylbenzenesulfonates, higher fatty acid amides, higher fatty acid esters, and waxes.

[0101] (C2) Examples of perchlorates include metal perchlorates and ammonium perchlorate.

[0102] Examples of the metal in the metal perchlorate include lithium, sodium, potassium, calcium, magnesium, strontium, barium, cadmium, and aluminum.

[0103] From the viewpoint of further increasing the static thermal stability and dynamic thermal stability of the vinyl chloride resin composition and further increasing the heat resistance of the resulting vinyl chloride resin molded article, the perchlorate (C2) is preferably sodium perchlorate, calcium perchlorate, or barium perchlorate.

[0104] The metal perchlorate may be an anhydrous or hydrated salt, and may be a metal perchlorate dissolved in an alcohol-based solvent such as butyl diglycol, a metal perchlorate dissolved in an ester-based solvent, or a dehydrate thereof.

[0105] The vinyl chloride resin composition preferably contains (C1) a hydrotalcite-type compound supporting perchloric acid, sodium perchlorate, calcium perchlorate, or barium perchlorate. The vinyl chloride resin composition more preferably contains (C1) a hydrotalcite-type compound supporting perchloric acid or sodium perchlorate, and even more preferably contains (C1) a hydrotalcite-type compound supporting perchloric acid. In these cases, the dynamic thermal stability of the vinyl chloride resin composition can be further improved, and the heat resistance of the resulting vinyl chloride resin molded article can be further improved.

[0106] The content of (C1) the hydrotalcite-type compound carrying perchloric acid or (C2) the perchlorate salt, based on 100% by weight of the vinyl chloride resin composition, is preferably 0.01% by weight or more, more preferably 0.1% by weight or more, even more preferably 0.3% by weight or more, and preferably 10.0% by weight or less, more preferably 5.0% by weight or less, and even more preferably 2.0% by weight or less. When the vinyl chloride resin composition contains (C1) the hydrotalcite-type compound carrying perchloric acid, the content of (C1) the hydrotalcite-type compound carrying perchloric acid, based on 100% by weight of the vinyl chloride resin composition, is preferably 0.01% by weight or more, more preferably 0.1% by weight or more, even more preferably 0.3% by weight or more, and preferably 10.0% by weight or less, more preferably 5.0% by weight or less, and even more preferably 2.0% by weight or less. When the vinyl chloride resin composition contains (C2) perchloric acid, the content of (C2) perchloric acid is preferably 0.01 wt% or more, more preferably 0.1 wt% or more, even more preferably 0.3 wt% or more, and preferably 10.0 wt% or less, more preferably 5.0 wt% or less, and even more preferably 2.0 wt% or less, based on 100 wt% of the vinyl chloride resin composition. When the content of (C1) perchloric acid-supported hydrotalcite-type compound or (C2) perchlorate salt is equal to or greater than the above-mentioned lower limit, the static thermal stability and dynamic thermal stability of the vinyl chloride resin composition can be further improved. When the content of (C1) perchloric acid-supported hydrotalcite-type compound or (C2) perchlorate salt is equal to or less than the above-mentioned upper limit, the flowability of the vinyl chloride resin composition during molding can be improved. In addition, when the vinyl chloride resin composition contains (C1) a hydrotalcite-type compound supporting perchloric acid and (C2) a perchlorate salt, the content of (C1) the hydrotalcite-type compound supporting perchloric acid or (C2) the perchlorate salt indicates the total content of (C1) the hydrotalcite-type compound supporting perchloric acid and (C2) the perchlorate salt (the same applies hereinafter).

[0107] The content of (C1) the hydrotalcite-type compound carrying perchloric acid or (C2) the perchlorate salt is preferably 0.01 part by weight or more, more preferably 0.2 part by weight or more, even more preferably 0.3 part by weight or more, and preferably 10.0 parts by weight or less, more preferably 5.0 parts by weight or less, and even more preferably 2.0 parts by weight or less, relative to 100 parts by weight of the chlorinated vinyl chloride resin. When the vinyl chloride resin composition contains (C1) the hydrotalcite-type compound carrying perchloric acid, the content of (C1) the hydrotalcite-type compound carrying perchloric acid is preferably 0.01 part by weight or more, more preferably 0.2 part by weight or more, even more preferably 0.3 part by weight or more, and preferably 10.0 parts by weight or less, more preferably 5.0 parts by weight or less, and even more preferably 2.0 parts by weight or less, relative to 100 parts by weight of the chlorinated vinyl chloride resin. When the vinyl chloride resin composition contains (C2) perchloric acid, the content of (C2) perchloric acid is preferably 0.01 parts by weight or more, more preferably 0.2 parts by weight or more, even more preferably 0.3 parts by weight or more, and preferably 10.0 parts by weight or less, more preferably 5.0 parts by weight or less, and even more preferably 2.0 parts by weight or less, per 100 parts by weight of the chlorinated vinyl chloride resin. When the content of (C1) perchloric acid-supported hydrotalcite-type compound or (C2) perchlorate salt is equal to or greater than the above-mentioned lower limit, the static thermal stability and dynamic thermal stability of the vinyl chloride resin composition can be further improved. When the content of (C1) perchloric acid-supported hydrotalcite-type compound or (C2) perchlorate salt is equal to or less than the above-mentioned upper limit, the flowability of the vinyl chloride resin composition during molding can be improved.

[0108] The vinyl chloride resin composition has the following structure A or the following structure B. The vinyl chloride resin composition may have the structure A, the structure B, or both the structure A and the structure B.

[0109] Structure A: The vinyl chloride resin composition contains (C1) a hydrotalcite-type compound supporting perchloric acid, and the ratio of the content of (B1) the aminouracil compound or (B2) the aminothiouracil compound to the content of (C1) the hydrotalcite-type compound supporting perchloric acid is 3.5 or less.

[0110] Structure B: The vinyl chloride resin composition contains (C2) a perchlorate, and the ratio of the content of (B1) the aminouracil compound or (B2) the aminothiouracil compound to the content of (C2) the perchlorate is 30.0 or less.

[0111] The ratio of the content of the (B1) aminouracil compound or (B2) aminothiouracil compound to the content of the (C1) perchloric acid-supported hydrotalcite-type compound is defined as the ratio (content of the (B1) aminouracil compound or (B2) aminothiouracil compound / content of the (C1) perchloric acid-supported hydrotalcite-type compound). When the vinyl chloride resin composition contains the (C1) perchloric acid-supported hydrotalcite-type compound, the ratio (content of the (B1) aminouracil compound or (B2) aminothiouracil compound / content of the (C1) perchloric acid-supported hydrotalcite-type compound) is 3.5 or less. The ratio (content of (B1) aminouracil compound or (B2) aminothiouracil compound / content of (C1) perchloric acid-supported hydrotalcite-type compound) is preferably 0.2 or more, more preferably 0.5 or more, even more preferably 1.0 or more, particularly preferably 1.2 or more, and most preferably 1.5 or more, and is preferably 3.0 or less, more preferably 2.8 or less, and even more preferably 2.5 or less. When the ratio (content of (B1) aminouracil compound or (B2) aminothiouracil compound / content of (C1) perchloric acid-supported hydrotalcite-type compound) is at least the lower limit mentioned above, the static thermal stability and dynamic thermal stability of the vinyl chloride resin composition can be further improved, and the heat resistance of the obtained vinyl chloride resin molded article can be further improved. When the ratio (content of the (B1) aminouracil compound or the (B2) aminothiouracil compound / content of the (C1) perchloric acid-supported hydrotalcite compound) is not more than the upper limit, the static thermal stability and dynamic thermal stability of the vinyl chloride resin composition can be further improved, and the heat resistance of the obtained vinyl chloride resin molded article can be further improved.

[0112] The ratio of the content of the (B1) aminouracil compound to the content of the (C1) perchloric acid-supported hydrotalcite-type compound is defined as the ratio ((B1) aminouracil compound content / (C1) perchloric acid-supported hydrotalcite-type compound content). When the vinyl chloride resin composition contains the (B1) aminouracil compound and the (C1) perchloric acid-supported hydrotalcite-type compound, the ratio ((B1) aminouracil compound content / (C1) perchloric acid-supported hydrotalcite-type compound content) is preferably 3.5 or less. The ratio ((B1) aminouracil compound content / (C1) perchloric acid-supported hydrotalcite-type compound content) is preferably 0.2 or more, more preferably 0.5 or more, even more preferably 1.0 or more, particularly preferably 1.2 or more, and most preferably 1.5 or more, and is preferably 3.0 or less, more preferably 2.8 or less, and even more preferably 2.5 or less. When the ratio (content of (B1) aminouracil compound / content of (C1) perchloric acid-supported hydrotalcite-type compound) is at least the lower limit, the static thermal stability and dynamic thermal stability of the vinyl chloride resin composition can be further increased, and the heat resistance of the obtained vinyl chloride resin molded article can be further increased. When the ratio (content of (B1) aminouracil compound / content of (C1) perchloric acid-supported hydrotalcite-type compound) is at most the upper limit, the static thermal stability and dynamic thermal stability of the vinyl chloride resin composition can be further increased, and the heat resistance of the obtained vinyl chloride resin molded article can be further increased.

[0113] The ratio of the content of the (B2) aminothiouracil compound to the content of the (C1) perchloric acid-supported hydrotalcite-type compound is defined as the ratio (content of the (B2) aminothiouracil compound / content of the (C1) perchloric acid-supported hydrotalcite-type compound). When the vinyl chloride resin composition contains the (B2) aminothiouracil compound and the (C1) perchloric acid-supported hydrotalcite-type compound, the ratio (content of the (B2) aminothiouracil compound / content of the (C1) perchloric acid-supported hydrotalcite-type compound) is preferably 3.5 or less. The ratio (content of the (B2) aminothiouracil compound / content of the (C1) perchloric acid-supported hydrotalcite-type compound) is preferably 0.2 or more, more preferably 0.5 or more, even more preferably 1.0 or more, particularly preferably 1.2 or more, and most preferably 1.5 or more, and is preferably 3.0 or less, more preferably 2.8 or less, and even more preferably 2.5 or less. When the ratio (content of the (B2) aminothiouracil compound / content of the (C1) perchloric acid-supported hydrotalcite-type compound) is at least as high as the lower limit, the static thermal stability and dynamic thermal stability of the vinyl chloride resin composition can be further increased, and the heat resistance of the vinyl chloride resin molded article obtained can be further increased. When the ratio (content of the (B2) aminothiouracil compound / content of the (C1) perchloric acid-supported hydrotalcite-type compound) is at most the upper limit, the static thermal stability and dynamic thermal stability of the vinyl chloride resin composition can be further increased, and the heat resistance of the vinyl chloride resin molded article obtained can be further increased.

[0114] The ratio of the content of the (B1) aminouracil compound or (B2) aminothiouracil compound to the content of the (C2) perchlorate is defined as the ratio (content of the (B1) aminouracil compound or (B2) aminothiouracil compound / content of the (C2) perchlorate). When the vinyl chloride resin composition contains the (C2) perchlorate, the ratio (content of the (B1) aminouracil compound or (B2) aminothiouracil compound / content of the (C2) perchlorate) is 30.0 or less. The ratio (content of the (B1) aminouracil compound or (B2) aminothiouracil compound / content of the (C2) perchlorate) is preferably 10.0 or more, more preferably 12.0 or more, even more preferably 15.0 or more, and preferably 27.0 or less, more preferably 26.0 or less, even more preferably 25.0 or less. When the ratio (content of (B1) aminouracil compound or (B2) aminothiouracil compound / content of (C2) perchlorate) is at least the lower limit, the static thermal stability and dynamic thermal stability of the vinyl chloride resin composition can be further increased, and the heat resistance of the obtained vinyl chloride resin molded article can be further increased. When the ratio (content of (B1) aminouracil compound or (B2) aminothiouracil compound / content of (C2) perchlorate) is at most the upper limit, the static thermal stability and dynamic thermal stability of the vinyl chloride resin composition can be further increased, and the heat resistance of the obtained vinyl chloride resin molded article can be further increased.

[0115] The ratio of the content of the (B1) aminouracil compound to the content of the (C2) perchlorate is defined as the ratio (content of the (B1) aminouracil compound / content of the (C2) perchlorate). When the vinyl chloride resin composition contains the (B1) aminouracil compound and the (C2) perchloric acid, the ratio (content of the (B1) aminouracil compound / content of the (C2) perchlorate) is preferably 30.0 or less. The ratio (content of the (B1) aminouracil compound / content of the (C2) perchlorate) is preferably 10.0 or more, more preferably 12.0 or more, even more preferably 15.0 or more, and is preferably 27.0 or less, more preferably 26.0 or less, and even more preferably 25.0 or less. When the ratio (content of the (B1) aminouracil compound / content of the (C2) perchlorate) is equal to or greater than the lower limit, the static thermal stability and dynamic thermal stability of the vinyl chloride resin composition can be further improved, and the heat resistance of the resulting vinyl chloride resin molded article can be further improved. When the ratio (content of (B1) aminouracil compound / content of (C2) perchlorate) is equal to or less than the upper limit, the static thermal stability and dynamic thermal stability of the vinyl chloride resin composition can be further improved, and the heat resistance of the obtained vinyl chloride resin molded article can be further improved.

[0116] The ratio of the content of the (B2) aminothiouracil compound to the content of the (C2) perchlorate is defined as the ratio (content of the (B2) aminothiouracil compound / content of the (C2) perchlorate). When the vinyl chloride resin composition contains the (B2) aminothiouracil compound and the (C2) perchloric acid, the ratio (content of the (B2) aminothiouracil compound / content of the (C2) perchlorate) is preferably 30.0 or less. The ratio (content of the (B2) aminothiouracil compound / content of the (C2) perchlorate) is preferably 10.0 or more, more preferably 12.0 or more, and even more preferably 15.0 or more, and is preferably 27.0 or less, more preferably 26.0 or less, and even more preferably 25.0 or less. When the ratio (content of (B2) aminothiouracil compound / content of (C2) perchlorate) is at least the lower limit, the static thermal stability and dynamic thermal stability of the vinyl chloride resin composition can be further increased, and the heat resistance of the vinyl chloride resin molded article obtained can be further increased. When the ratio (content of (B2) aminothiouracil compound / content of (C2) perchlorate) is at most the upper limit, the static thermal stability and dynamic thermal stability of the vinyl chloride resin composition can be further increased, and the heat resistance of the vinyl chloride resin molded article obtained can be further increased.

[0117] <(D1) Alkaline Earth Metal Hydroxide and (D2) Alkaline Earth Metal Oxide> The vinyl chloride resin composition contains (D1) an alkaline earth metal hydroxide or (D2) an alkaline earth metal oxide.

[0118] Examples of the alkaline earth metal hydroxide (D1) include magnesium hydroxide, calcium hydroxide, barium hydroxide, etc. The alkaline earth metal hydroxide (D1) may be used alone or in combination of two or more.

[0119] Examples of the alkaline earth metal oxide (D2) include magnesium oxide, calcium oxide, barium oxide, etc. The alkaline earth metal oxide (D2) may be used alone or in combination of two or more.

[0120] From the viewpoint of further increasing the static thermal stability and dynamic thermal stability of the vinyl chloride resin composition and further increasing the heat resistance of the resulting vinyl chloride resin molded article, it is preferable that the alkaline earth metal hydroxide (D1) contains magnesium hydroxide or calcium hydroxide.

[0121] From the viewpoint of further increasing the static thermal stability and dynamic thermal stability of the vinyl chloride resin composition and further increasing the heat resistance of the resulting vinyl chloride resin molded article, it is preferable that the alkaline earth metal oxide (D2) contains magnesium oxide or calcium oxide.

[0122] From the viewpoint of further increasing the static thermal stability and dynamic thermal stability of the vinyl chloride resin composition and further increasing the heat resistance of the resulting vinyl chloride resin molded article, the vinyl chloride resin composition preferably contains (D1) an alkaline earth metal hydroxide, and the (D1) alkaline earth metal hydroxide more preferably contains magnesium hydroxide or calcium hydroxide. From the viewpoint of further increasing the static thermal stability and dynamic thermal stability of the vinyl chloride resin composition and further increasing the heat resistance of the resulting vinyl chloride resin molded article, the vinyl chloride resin composition preferably contains (D1) an alkaline earth metal hydroxide, and more preferably contains magnesium hydroxide or calcium hydroxide.

[0123] The content of (D1) alkaline earth metal hydroxide or (D2) alkaline earth metal oxide, based on 100% by weight of the vinyl chloride resin composition, is preferably 0.1% by weight or more, more preferably 0.2% by weight or more, even more preferably 0.3% by weight or more, and preferably 5.0% by weight or less, more preferably 3.0% by weight or less, and even more preferably 2.0% by weight or less. When the vinyl chloride resin composition contains (D1) alkaline earth metal hydroxide, the content of (D1) alkaline earth metal hydroxide, based on 100% by weight of the vinyl chloride resin composition, is preferably 0.1% by weight or more, more preferably 0.2% by weight or more, even more preferably 0.3% by weight or more, and preferably 5.0% by weight or less, more preferably 3.0% by weight or less, and even more preferably 2.0% by weight or less. When the vinyl chloride resin composition contains (D2) an alkaline earth metal oxide, the content of (D2) alkaline earth metal oxide is preferably 0.1 wt% or more, more preferably 0.2 wt% or more, even more preferably 0.3 wt% or more, and preferably 5.0 wt% or less, more preferably 3.0 wt% or less, and even more preferably 2.0 wt% or less, based on 100 wt% of the vinyl chloride resin composition. When the content of (D1) alkaline earth metal hydroxide or (D2) alkaline earth metal oxide is equal to or greater than the above-mentioned lower limit, the static thermal stability and dynamic thermal stability of the vinyl chloride resin composition can be further improved. When the content of (D1) alkaline earth metal hydroxide or (D2) alkaline earth metal oxide is equal to or less than the above-mentioned upper limit, the flowability of the vinyl chloride resin composition during molding can be improved. In addition, when the vinyl chloride resin composition contains (D1) an alkaline earth metal hydroxide and (D2) an alkaline earth metal oxide, the content of (D1) an alkaline earth metal hydroxide or (D2) an alkaline earth metal oxide indicates the total content of (D1) an alkaline earth metal hydroxide and (D2) an alkaline earth metal oxide (the same applies hereinafter).

[0124] The content of (D1) alkaline earth metal hydroxide or (D2) alkaline earth metal oxide is preferably at least 0.1 part by weight, more preferably at least 0.2 part by weight, even more preferably at least 0.3 part by weight, and preferably at most 5.0 parts by weight, more preferably at most 3.0 parts by weight, and even more preferably at most 2.0 parts by weight, per 100 parts by weight of the chlorinated vinyl chloride resin. When the vinyl chloride resin composition contains (D1) alkaline earth metal hydroxide, the content of (D1) alkaline earth metal hydroxide is preferably at least 0.1 part by weight, more preferably at least 0.2 part by weight, even more preferably at least 0.3 part by weight, and preferably at most 5.0 parts by weight, more preferably at most 3.0 parts by weight, and even more preferably at most 2.0 parts by weight, per 100 parts by weight of the chlorinated vinyl chloride resin. When the vinyl chloride resin composition contains (D2) an alkaline earth metal oxide, the content of (D2) alkaline earth metal oxide is preferably at least 0.1 part by weight, more preferably at least 0.2 part by weight, even more preferably at least 0.3 part by weight, and preferably at most 5.0 parts by weight, more preferably at most 3.0 parts by weight, and even more preferably at most 2.0 parts by weight, per 100 parts by weight of the chlorinated vinyl chloride resin. When the content of (D1) an alkaline earth metal hydroxide or (D2) an alkaline earth metal oxide is at least the above-mentioned lower limit, the static thermal stability and dynamic thermal stability of the vinyl chloride resin composition can be further improved. When the content of (D1) an alkaline earth metal hydroxide or (D2) an alkaline earth metal oxide is at most the above-mentioned upper limit, the flowability of the vinyl chloride resin composition during molding can be improved.

[0125] The ratio of the content of the (B1) aminouracil compound or (B2) aminothiouracil compound to the content of the (D1) alkaline earth metal hydroxide or (D2) alkaline earth metal oxide is defined as the ratio (content of the (B1) aminouracil compound or (B2) aminothiouracil compound / content of the (D1) alkaline earth metal hydroxide or (D2) alkaline earth metal oxide). This ratio (content of the (B1) aminouracil compound or (B2) aminothiouracil compound / content of the (D1) alkaline earth metal hydroxide or (D2) alkaline earth metal oxide) is preferably 0.1 or more, more preferably 0.5 or more, and even more preferably 1.0 or more, and is preferably 5.0 or less, more preferably 4.5 or less, and even more preferably 3.0 or less. When the ratio (content of (B1) aminouracil compound or (B2) aminothiouracil compound / content of (D1) alkaline earth metal hydroxide or (D2) alkaline earth metal oxide) is at least the lower limit, the static thermal stability and dynamic thermal stability of the vinyl chloride resin composition can be further improved. When the ratio (content of (B1) aminouracil compound or (B2) aminothiouracil compound / content of (D1) alkaline earth metal hydroxide or (D2) alkaline earth metal oxide) is at most the upper limit, the static thermal stability and dynamic thermal stability of the vinyl chloride resin composition can be further improved.

[0126] <Impact Modifier> The vinyl chloride resin composition preferably contains an impact modifier. When the vinyl chloride resin composition contains the impact modifier, the heat resistance and impact resistance of the resulting vinyl chloride resin molded article can be further improved.

[0127] Examples of the impact modifier include styrene-diene copolymers, acrylic copolymers, silicone-acrylic copolymers, chlorinated polyethylene, etc. The impact modifiers may be used alone or in combination of two or more.

[0128] Examples of the diene component that is a polymerization component of the styrene-diene copolymer include butadiene, isoprene, chloroprene, etc. The content of the diene-derived skeleton (diene component) in 100% by weight of the polymerization components of the styrene-diene copolymer is preferably 55% by weight or more.

[0129] From the viewpoint of further increasing the impact resistance of the resulting vinyl chloride resin molded article, the styrene-diene copolymer is preferably a styrene-conjugated diene copolymer, more preferably a styrene-butadiene copolymer. Examples of the styrene-conjugated diene copolymer include methyl methacrylate-butadiene-styrene copolymer (MBS), acrylonitrile-butadiene-styrene copolymer (ABS), and methyl methacrylate-acrylonitrile-butadiene-styrene copolymer (MABS).

[0130] From the viewpoint of further increasing the impact resistance of the resulting vinyl chloride resin molded article, the impact modifier preferably contains a methyl methacrylate-butadiene-styrene copolymer or an acrylonitrile-butadiene-styrene copolymer.

[0131] The acrylic copolymer may be an acrylic acid ester or a methacrylic acid ester.

[0132] The content of the conjugated diene-derived skeleton in 100% by weight of the styrene-conjugated diene copolymer is preferably 55% by weight or more, and preferably 70% by weight or less. When the content of the conjugated diene-derived skeleton is equal to or more than the above lower limit, the impact resistance of the obtained vinyl chloride resin molded article can be further improved. When the content of the conjugated diene-derived skeleton is equal to or less than the above upper limit, the flowability of the vinyl chloride resin composition during molding can be improved. When the conjugated diene-derived skeleton is a butadiene-derived skeleton, the content of the conjugated diene-derived skeleton indicates the content of the butadiene-derived skeleton.

[0133] When the vinyl chloride resin composition contains an impact modifier, the content of the impact modifier is preferably 1 part by weight or more, more preferably 3 parts by weight or more, and even more preferably 5 parts by weight or more, and is preferably 20 parts by weight or less, more preferably 10 parts by weight or less, relative to 100 parts by weight of the chlorinated vinyl chloride resin. When the content of the impact modifier is equal to or more than the above-mentioned lower limit and equal to or less than the above-mentioned upper limit, the impact resistance of the obtained vinyl chloride resin molded article can be further improved.

[0134] <Other Components> The vinyl chloride resin composition may contain additives as needed. Examples of the additives include heat stabilizers, heat stabilization aids, antioxidants, lubricants, processing aids, heat resistance improvers, UV absorbers, antistatic agents, light stabilizers, fillers, colorants, and plasticizers. The additives may be used alone or in combination of two or more.

[0135] Examples of the heat stabilizer include an organotin-based heat stabilizer, a lead-based heat stabilizer, and an organic acid metal salt-based heat stabilizer. The heat stabilizer may be used alone or in combination of two or more.

[0136] Examples of the heat stabilization aid include β-diketone compounds, epoxidized soybean oil, phosphate esters, hydrotalcite, and zeolites. Examples of the β-diketone compounds include acetylacetone, dibenzoylmethane, steroylbenzoylmethane, and dihydroacetic acid. One type of the heat stabilization aid may be used alone, or two or more types may be used in combination.

[0137] Examples of the antioxidant include phenol-based antioxidants, amine-based antioxidants, phosphorus-based antioxidants, sulfur-based antioxidants, etc. The antioxidants may be used alone or in combination of two or more.

[0138] Examples of the lubricant include internal lubricants and external lubricants. The internal lubricant is used to reduce the flow viscosity of the molten resin during molding and prevent frictional heat generation. Examples of the internal lubricant include butyl stearate, lauryl alcohol, stearyl alcohol, epoxidized soybean oil, glycerin monostearate, stearic acid, and bisamide. The external lubricant is used to improve the sliding effect between the molten resin and the metal surface during molding. Examples of the external lubricant include paraffin wax, polyethylene wax, polyolefin wax, ester wax, and montanic acid wax. Only one type of the lubricant may be used, or two or more types may be used in combination.

[0139] Examples of the processing aid include acrylic processing aids. Examples of the acrylic processing aid include alkyl acrylate-alkyl methacrylate copolymers having a weight-average molecular weight of 100,000 to 2,000,000. Specific examples include n-butyl acrylate-methyl methacrylate copolymers and 2-ethylhexyl acrylate-methyl methacrylate-butyl methacrylate copolymers. Only one type of the processing aids may be used, or two or more types may be used in combination.

[0140] Examples of the heat resistance improver include α-methylstyrene-based and N-phenylmaleimide-based resins, etc. The heat resistance improver may be used alone or in combination of two or more.

[0141] Examples of the ultraviolet absorber include salicylic acid ester-based ultraviolet absorbers, benzophenone-based ultraviolet absorbers, benzotriazole-based ultraviolet absorbers, and cyanoacrylate-based ultraviolet absorbers. The ultraviolet absorbers may be used alone or in combination of two or more.

[0142] Examples of the light stabilizer include hindered amine light stabilizers, etc. The light stabilizers may be used alone or in combination of two or more.

[0143] Examples of the filler include calcium carbonate, talc, etc. The filler may be used alone or in combination of two or more.

[0144] From the viewpoint of cost reduction, the filler preferably contains calcium carbonate.

[0145] The content of the filler in 100% by weight of the vinyl chloride resin composition is preferably 30% by weight or less, more preferably 15% by weight or less, even more preferably 10% by weight or less, and particularly preferably 3% by weight or less. When the content of the filler is equal to or less than the above upper limit, thermal stability during hot molding can be further improved. The lower limit of the content of the filler in 100% by weight of the vinyl chloride resin composition is not particularly limited. The content of the filler in 100% by weight of the vinyl chloride resin composition may be 0% by weight or more, may exceed 0% by weight, or may be 0.1% by weight or more. The range of the content of the filler in 100% by weight of the vinyl chloride resin composition can be set by appropriately selecting the above lower limit and upper limit.

[0146] The vinyl chloride resin composition preferably does not contain the filler or contains 15.0 parts by weight or less of the filler per 100 parts by weight of the chlorinated vinyl chloride resin. The vinyl chloride resin composition more preferably does not contain the filler or contains 8.0 parts by weight or less of the filler per 100 parts by weight of the chlorinated vinyl chloride resin. When the vinyl chloride resin composition contains the filler, the content of the filler per 100 parts by weight of the chlorinated vinyl chloride resin is preferably 15.0 parts by weight or less, more preferably 10.0 parts by weight or less, even more preferably 8.0 parts by weight or less, particularly preferably 6.0 parts by weight or less, and most preferably 5.0 parts by weight or less. When the content of the filler is equal to or less than the upper limit, thermal stability during hot molding can be further improved. When the vinyl chloride resin composition contains the filler, there is no particular lower limit on the content of the filler per 100 parts by weight of the chlorinated vinyl chloride resin. The content of the filler per 100 parts by weight of the chlorinated vinyl chloride resin may be 0 parts by weight or more, more than 0 parts by weight, 0.1 parts by weight or more, or 0.5 parts by weight or more. From the viewpoint of further improving thermal stability during hot molding, it is most preferable that the vinyl chloride resin composition does not contain the filler. The range of the content of the filler per 100 parts by weight of the chlorinated vinyl chloride resin can be set by appropriately selecting the lower limit and the upper limit.

[0147] Examples of the colorant include pigments and dyes. The colorant preferably contains a pigment. Examples of the pigment include organic pigments and inorganic pigments. Examples of the organic pigment include azo-based organic pigments, phthalocyanine-based organic pigments, threne-based organic pigments, and dye lake-based organic pigments. Examples of the inorganic pigment include oxide-based inorganic pigments, molybdenum chromate-based inorganic pigments, sulfide / selenide-based inorganic pigments, and ferrocyanide-based inorganic pigments. Only one type of the colorant may be used, or two or more types may be used in combination.

[0148] From the viewpoint of improving the design of the vinyl chloride resin molded article to be obtained, the vinyl chloride resin composition preferably contains a colorant. The colorant may be a black colorant, a red colorant, a blue colorant, a yellow colorant, or a white colorant. The colorant may also be a gray colorant.

[0149] The content of the colorant is not particularly limited. The content of the colorant in 100% by weight of the vinyl chloride resin composition is preferably 0.02% by weight or more, more preferably 0.05% by weight or more, even more preferably 0.10% by weight or more, and is preferably 10% by weight or less, more preferably 8.0% by weight or less, even more preferably 6.0% by weight or less, and particularly preferably 4.0% by weight or less. When the content of the colorant is equal to or more than the lower limit and equal to or less than the upper limit, it is easy to appropriately color the vinyl chloride resin molded article obtained.

[0150] The content of the colorant relative to 100 parts by weight of the chlorinated vinyl chloride resin is preferably at least 0.02 parts by weight, more preferably at least 0.05 parts by weight, even more preferably at least 0.10 parts by weight, and is preferably at most 10 parts by weight, more preferably at most 8.0 parts by weight, even more preferably at most 6.0 parts by weight, and particularly preferably at most 4.0 parts by weight. When the content of the colorant is at least the above-mentioned lower limit and at most the above-mentioned upper limit, it is easy to appropriately color the obtained vinyl chloride resin molded article.

[0151] The plasticizer may be added to improve processability during molding. Since the addition of a plasticizer may reduce the heat resistance of the molded body, it is preferable to add a small amount of plasticizer. Examples of the plasticizer include dibutyl phthalate, di-2-ethylhexyl phthalate, and di-2-ethylhexyl adipate. Only one type of the plasticizer may be used, or two or more types may be used in combination.

[0152] (Vinyl chloride resin molded article) The vinyl chloride resin molded article according to the present invention is a molded article of the vinyl chloride resin composition described above. The vinyl chloride resin molded article is formed using the vinyl chloride resin composition. The vinyl chloride resin molded article is obtained by molding the vinyl chloride resin composition.

[0153] The vinyl chloride resin molded article according to the present invention has the above-mentioned structure, and therefore can improve static thermal stability and prevent appearance defects.

[0154] Furthermore, since the vinyl chloride resin molded article according to the present invention has the above-mentioned features, it is possible to improve heat resistance and increase the Vicat softening temperature.

[0155] The Vicat softening temperature of the vinyl chloride resin molded article is preferably 108°C or higher, more preferably 110°C or higher. When the Vicat softening temperature is equal to or higher than the lower limit, the heat resistance of the vinyl chloride resin molded article can be further improved. The Vicat softening temperature of the vinyl chloride resin molded article may be 300°C or lower, 220°C or lower, 200°C or lower, 190°C or lower, 180°C or lower, or 150°C or lower. The range of the Vicat softening temperature of the vinyl chloride resin molded article can be set by appropriately selecting the lower limit and the upper limit.

[0156] Examples of the shape of the vinyl chloride resin molded article include a pipe, a plate, and a container. The vinyl chloride resin molded article is preferably in a pipe (tubular) shape. Since the static thermal stability and heat resistance can be improved, the vinyl chloride resin molded article is preferably used as a vinyl chloride resin pipe. Since the static thermal stability and heat resistance can be improved, the vinyl chloride resin molded article is also preferably used as a rain gutter.

[0157] The method for molding the vinyl chloride resin composition is not particularly limited, and examples of the method for molding the vinyl chloride resin composition include extrusion molding, injection molding, calendar molding, blow molding, and press molding.

[0158] Examples of molding machines used for molding include single-screw extruders, twin-screw counter-rotating parallel extruders, twin-screw counter-rotating conical extruders, and twin-screw co-rotating extruders. The heating temperature when molding using the above molding machines is preferably 80°C or higher and preferably 140°C or lower.

[0159] From the viewpoint of more effectively preventing the occurrence of poor appearance of the vinyl chloride resin molded article and further improving the heat resistance, the vinyl chloride resin molded article is preferably a vinyl chloride extrusion molded article of the vinyl chloride resin composition described above.

[0160] Since the static thermal stability and heat resistance can be improved, the vinyl chloride resin molded product according to the present invention is suitable for use as a vinyl chloride resin pipe.Since the static thermal stability and heat resistance can be improved, the vinyl chloride resin molded product according to the present invention is suitable for use as a vinyl chloride resin pipe.

[0161] From the viewpoint of further increasing the mechanical strength and impact resistance of the vinyl chloride resin pipe, the vinyl chloride resin pipe is preferably a rigid vinyl chloride resin pipe. From the viewpoint of further increasing the mechanical strength and impact resistance of the vinyl chloride resin pipe, the molded product of the vinyl chloride resin composition (vinyl chloride resin molded product) is preferably a rigid vinyl chloride resin molded product. From the viewpoint of further increasing the mechanical strength and impact resistance of the vinyl chloride resin pipe, the vinyl chloride resin pipe preferably includes a rigid vinyl chloride resin molded product.

[0162] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples.

[0163] The following materials were prepared:

[0164] (A) Chlorinated vinyl chloride resins Chlorinated vinyl chloride resin A ("HA-57K" manufactured by Tokuyama Sekisui Kogyo Co., Ltd., average degree of polymerization: 1000, chlorine content: 66.5% by weight) Chlorinated vinyl chloride resin B ("HA-57F" manufactured by Tokuyama Sekisui Kogyo Co., Ltd., average degree of polymerization: 1000, chlorine content: 64% by weight)

[0165] (B1) Aminouracil compound 6-amino-1,3-dimethyluracil (Tokyo Chemical Industry Co., Ltd.)

[0166] (C1) Hydrotalcite-type compound supporting perchloric acid: Hydrotalcite supporting perchloric acid ("Alcamizer 5" manufactured by Kyowa Chemical Industry Co., Ltd.)

[0167] (C2) Perchlorate: Sodium perchlorate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.)

[0168] (D1) Alkaline earth metal hydroxides: Magnesium hydroxide (Kisuma 5A, manufactured by Kyowa Chemical Industry Co., Ltd.); Calcium hydroxide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.)

[0169] Impact modifier (methyl methacrylate-butadiene-styrene copolymer (MBS), Kaneka Corporation "Kane Ace-564") Lubricant (ester wax, Emery Oleochemicals "VPN963") Lubricant (polyethylene wax, Mitsui Chemicals "Hiwax 220MP")

[0170] (Example 1) Preparation of vinyl chloride resin composition: The materials shown in Table 1 were blended in the amounts shown in Table 1, and the blended materials were stirred and mixed at 110°C for 5 minutes using a Henschel mixer (manufactured by Kawada Kogyosho) to obtain a vinyl chloride resin composition.

[0171] Examples 2 to 6 and Comparative Examples 1 to 4 Vinyl chloride resin compositions were obtained in the same manner as in Example 1, except that the formulations of the vinyl chloride resin compositions were changed as shown in Tables 1 to 3.

[0172] (Evaluation) (1) Static thermal stability The vinyl chloride resin composition obtained was kneaded under the following conditions to obtain a sheet (vinyl chloride resin molded article) having a thickness of 0.6 mm.

[0173] [Mixing conditions] Mixing roll: manufactured by Yasuda Seiki Seisakusho Co., Ltd. Roll temperature: 190°C Roll time: 3 minutes (after wrapping)

[0174] The obtained sheet was cut into a length of 30 mm and a width of 30 mm to obtain a test sample. The test sample was placed in a Geer oven set at an internal temperature of 200°C and heated. The test sample in the Geer oven was visually inspected for coloration every 10 minutes from the start of heating, and the time until it was confirmed that the sample had turned black (Geer oven heat resistance time) was recorded. The static thermal stability of the vinyl chloride resin composition was evaluated according to the following criteria.

[0175] [Criteria for determining static heat stability] ○: Heat resistance time in a gear oven is 50 minutes or more ×: Heat resistance time in a gear oven is less than 50 minutes

[0176] (2) Dynamic thermal stability: 65 g of the obtained vinyl chloride resin composition was filled into a "Labo Plastomill" manufactured by Toyo Seiki Seisaku-sho, Ltd., and kneaded under the following conditions, and the heat resistance time of the plast until decomposition was recorded. The dynamic thermal stability of the vinyl chloride resin composition was evaluated according to the following criteria.

[0177] [Kneading conditions] Temperature: 200°C, Rotation speed: 50 rpm, Preheating time: 2 minutes

[0178] [Criteria for determining dynamic thermal stability] ○○: Plast heat resistance time is 10 minutes or more ○: Plast heat resistance time is 8 minutes or more but less than 10 minutes ×: Plast heat resistance time is less than 8 minutes

[0179] (3) Heat Resistance The sheet obtained in (1) Evaluation of Static Thermal Stability was molded under the following conditions to obtain a sheet (vinyl chloride resin molded article) having a thickness of 3.0 mm.

[0180] [Molding conditions] Press machine: Kodaira Seisakusho hot press molding machine (press surface material: SUS304) Press temperature: 200°C Press time: preheating 3 minutes + pressure 2 minutes Press pressure: 200 kgf / cm ２

[0181] The obtained sheet was cut into a length of 30 mm and a width of 30 mm to obtain a test sample. The Vicat softening temperature of the test sample was measured in accordance with JIS K7206. The heat resistance of the vinyl chloride resin molded article was evaluated according to the following criteria.

[0182] [Criteria for judging heat resistance] ○○: Vicat softening temperature is 110°C or higher ○: Vicat softening temperature is 108°C or higher and lower than 110°C ×: Vicat softening temperature is lower than 108°C

[0183] The compositions of the vinyl chloride resin compositions and the results are shown in Tables 1 to 3.

[0184]

[0185]

[0186]

[0187] Specific examples are shown in which the vinyl chloride resin composition contains an aminouracil compound (B1). Even when an aminothiouracil compound (B2) is used instead of the aminouracil compound (B1), the static thermal stability, dynamic thermal stability, and heat resistance can be improved.

[0188] Other formulation examples 1 to 5 of vinyl chloride resin compositions are shown below.

[0189]

Claims

1. A vinyl chloride resin composition comprising a chlorinated vinyl chloride resin, an aminouracil compound or an aminothiouracil compound, a hydrotalcite-type compound carrying perchloric acid or a perchlorate, and an alkaline earth metal hydroxide or an alkaline earth metal oxide, and having the following structure A or structure B. Structure A: The vinyl chloride resin composition comprises the hydrotalcite-type compound carrying perchloric acid, and the ratio of the content of the aminouracil compound or the aminothiouracil compound to the content of the hydrotalcite-type compound carrying perchloric acid is 3.5 or less. Structure B: The vinyl chloride resin composition comprises the perchlorate, and the ratio of the content of the aminouracil compound or the aminothiouracil compound to the content of the perchlorate is 30.0 or less.

2. The vinyl chloride resin composition according to claim 1, wherein the vinyl chloride resin composition contains an alkaline earth metal hydroxide, and the alkaline earth metal hydroxide contains magnesium hydroxide or calcium hydroxide.

3. The vinyl chloride resin composition according to claim 1 or 2, wherein the ratio of the content of the aminouracil compound or the aminothiouracil compound to the content of the alkaline earth metal hydroxide or the alkaline earth metal oxide is 5.0 or less.

4. The vinyl chloride resin composition according to any one of claims 1 to 3, wherein the chlorinated vinyl chloride resin has a chlorine content of 60% by weight or more.

5. The vinyl chloride resin composition according to claim 4, wherein the chlorinated vinyl chloride resin has a chlorine content of 64% by weight or more.

6. The vinyl chloride resin composition according to any one of claims 1 to 5, wherein the vinyl chloride resin composition contains an impact modifier, and the content of the impact modifier is 1 part by weight or more and 20 parts by weight or less per 100 parts by weight of the chlorinated vinyl chloride resin.

7. A vinyl chloride resin molded article, which is a molded article of the vinyl chloride resin composition according to any one of claims 1 to 6.

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