JP2002138179A - Vinyl chloride resin composition and molded article using the same - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To have an excellent woody feeling and to prevent discoloration, fading or chalking even when irradiated with ultraviolet rays for a long time.
To provide a vinyl chloride resin composition containing a lead-free heat stabilizer and a molded article thereof. SOLUTION: Per 100 parts by weight of vinyl chloride resin,
5-150 parts by weight of wood flour, calcium-zinc heat stabilizer
A vinyl chloride resin composition containing 5 to 5 parts by weight and 0.1 to 10 parts by weight of an oxide or hydroxide of a long-period Group 2 element.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vinyl chloride resin composition having good weather resistance and a molded article using the same. More specifically, the invention relates to wood flour and calcium-
A vinyl chloride resin composition containing a zinc heat stabilizer and a molded article thereof, even if exposed to ultraviolet rays for a long time, discoloration,
The present invention relates to a vinyl chloride resin composition which is less likely to cause fading or chalking and has a rich woody feel, and a molded product thereof.

[0002]

2. Description of the Related Art In recent years, it has been frequently practiced to mix wood powder with a vinyl chloride resin for the purpose of producing an appearance and feel similar to wood and for protecting wood resources. . When a deck material, a door frame, a bay window frame, a baseboard and the like formed from a vinyl chloride resin composition containing wood powder are used in a sunny place, there is a problem that discoloration, fading or chalking occurs after a long period of time. . Therefore, as a vinyl chloride resin composition having little chalking, a composition containing copper acetate (JP-B-62-41532) has been used.
JP-A-6-322206), a composition containing copper acetate and a hydrotalcite compound (JP-A-6-322206), and a composition containing copper acetate and magnesium oxide and / or magnesium hydroxide (JP-A-11-332050). ), A composition containing an A-type zeolite substituted with copper or cobalt (Japanese Patent Publication No. 1-44211), a composition containing a copper-containing zeolite, basic copper carbonate or copper aromatic carboxylate (Japanese Patent Application Laid-Open No. No. 302486) has been proposed. However, even with these, discoloration, fading, chalking and the like could not be prevented in the vinyl chloride resin composition containing wood powder.

[0003] The applicant of the present invention has previously disclosed in a vinyl chloride resin composition containing wood flour, a lower fatty acid copper [II] salt and specific pigments such as quinacridone pigments and perylene pigments in addition to hydrotalcite. It has been disclosed that when added, a molded article having good weather resistance, in which discoloration, fading, chalking and the like are less likely to occur outdoors, can be obtained (JP-A-10-15).
No. 2593). Such an effect in blending wood flour is particularly large when a lead-based heat stabilizer is used. However, in the PVC resin processing industry, lead-based thermal stabilizers are now being replaced with non-lead-based thermal stabilizers in order to prevent the occurrence of disasters such as contamination of groundwater by elution of stabilizers from plastic waste. Investigations have been made to replace it with an agent, and again, there is an increasing demand for improving the weather resistance of a vinyl chloride resin composition containing wood flour.

[0004]

DISCLOSURE OF THE INVENTION The present invention relates to a vinyl chloride blended with a lead-free heat stabilizer which has an excellent woody feel and does not easily cause discoloration, fading or chalking even when used outdoors for a long period of time. The object of the present invention is to provide a resin composition and a molded product thereof. The present inventors have conducted intensive studies to solve the above problems, and as a result of blending magnesium oxide with a calcium-zinc heat stabilizer in a vinyl chloride resin composition containing wood flour, The present inventors have found that a molded article which hardly causes discoloration, fading and chalking even when used can be obtained, and based on this finding, the present invention has been completed.

[0005]

That is, according to the present invention, the following (1) to (4) are provided. (1) A vinyl chloride resin composition comprising at least a vinyl chloride resin, wood flour, a calcium-zinc heat stabilizer, and a compound of a long-period Group 2 element, wherein each of the compositions is based on 100 parts by weight of the vinyl chloride resin. Wood flour: 5-150 parts by weight, Calcium-Zinc heat stabilizer: 0.5-5 parts by weight, Long-period Group 2 element oxide or hydroxide: 0.1-10
Parts by weight, (2) vinyl chloride resin 1
At least one part selected from the group consisting of quinacridone pigments, perylene pigments, polyazo condensed pigments, isoindolinone pigments, copper phthalocyanine pigments, cadmium pigments, titanium white and carbon black, relative to 00 parts by weight. (3) The vinyl chloride resin composition according to (1), wherein the pigment contains 0.1 to 10 parts by weight of a pigment, (3) the chloride according to (1) or (2), wherein the long-period Group 2 element is magnesium. Vinyl resin composition, and (4)
A molded article obtained by molding the vinyl chloride resin composition according to any one of the above (1) to (3).

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail. Examples of the vinyl chloride resin used in the composition of the present invention include vinyl chloride homopolymers and vinyl chloride copolymers having a vinyl chloride repeating unit of 50% by weight or more. Examples of monomers copolymerized with vinyl chloride include α-olefins such as ethylene and propylene;
Halogenated olefins such as allyl chloride, vinylidene chloride, vinyl fluoride and ethylene trifluoride; vinyl acetate;
Carboxylic acid vinyl esters such as vinyl propionate; vinyl ethers such as isobutyl vinyl ether and cetyl vinyl ether; allyl ethers such as allyl-3-chloro-2-oxypropyl ether and allyl glycidyl ether; (meth) acrylic acid (acrylic acid) And / or methacrylic acid; the same shall apply hereinafter), unsaturated carboxylic acids such as maleic acid, itaconic acid and maleic anhydride and their acid anhydrides; 2-hydroxyethyl (meth) acrylate, (meth) acrylic acid Esters of unsaturated carboxylic acids such as methyl acrylate, monomethyl maleate and diethyl maleate; unsaturated nitriles such as (meth) acrylonitrile; acrylamide, N-methylolacrylamide, acrylamide-2-methylpropanesulfonic acid, (meth) Acri Acrylamides such as amidopropyl trimethyl ammonium chloride; allyl amine benzoates, and the like allylamine and its derivatives such as diallyl dimethyl ammonium chloride. One or more of these monomers can be used.

The vinyl chloride resin used in the present invention includes resins such as ethylene-vinyl acetate copolymer, ethylene-methyl methacrylate copolymer, ethylene-ethyl acrylate copolymer, and chlorinated polyethylene. A resin obtained by graft polymerization of vinyl chloride or the above-described copolymerizable monomer with vinyl chloride is also included. These vinyl chloride resins may be produced by any conventionally known production method such as suspension polymerization, emulsion polymerization, solution polymerization, or bulk polymerization. The average degree of polymerization of the vinyl chloride resin is JIS K
The value measured according to 6721 is preferably from 400 to 1,500, more preferably from 600 to 1,100. If the average degree of polymerization of the vinyl chloride resin is excessively small, the resulting molded article may have poor mechanical properties, resulting in poor color fastness and chalking resistance. If the average polymerization degree of the vinyl chloride resin is excessively large, kneading and molding become difficult, and it may be difficult to uniformly disperse the wood powder in the resin composition.

[0008] In the present invention, wood flour is blended. There is no particular limitation on the tree species of the wood flour used in the present invention, for example, cedar, hemlock, timber pieces of coniferous or hardwood such as Lauan,
Planes, sawdust and the like can be used. In order to obtain wood flour from these woods, for example, the wood is made into a powder having an average particle size of preferably 30 to 500 μm, more preferably 50 to 100 μm using a crusher. The shape of the wood flour is preferably relatively round. The average particle size of the wood flour refers to a reading of the value of the mesh corresponding to 50% by weight of the powder by classifying the powder with a sieve to form a cumulative weight% curve with respect to the mesh. If the average particle size of the wood flour is excessively small, the bulk specific gravity becomes small and the mixing operability for preparing the composition may be deteriorated. If the average particle size of the wood flour is excessively large, the surface of the molded product may be roughened and the woody feeling may be reduced.

[0009] In the present invention, as wood powder, Japanese Patent Application Laid-Open Nos. 5-177610 and 5-26170
As disclosed in Japanese Patent Publication No. 8-86, wood powder having hard small particles adhered to the surface can be used. In the present invention, the amount of the wood flour is 5 to 150 parts by weight, preferably 15 to 120 parts by weight per 100 parts by weight of the vinyl chloride resin,
More preferably, it is 25 to 100 parts by weight. If the content of the wood powder is excessively small, it may be difficult to give the molded article a good woody feel and appearance close to that of natural wood. On the other hand, when the content of the wood powder is excessively large, the dispersibility of the wood powder in the resin becomes uneven, and the mechanical strength of the molded product may be reduced. The water content of the wood flour is preferably 10% by weight or less, more preferably 5% by weight or less.

In the present invention, a calcium-zinc heat stabilizer, which is a non-toxic heat stabilizer, is blended. The calcium-zinc heat stabilizer used in the present invention is, for example, a heat stabilizer comprising a coprecipitated compound of calcium and zinc, or a mixture of a calcium compound and a zinc compound. As the calcium compound and the zinc compound, lauric acid, stearic acid, 2-
10 to 10 carbon atoms such as ethylhexenoic acid and ricinoleic acid
Examples include 22 saturated or unsaturated fatty acid salts, naphthenates, phenates, organic phosphites, and the like. Zinc compounds generally do not easily cause initial coloring when heated alone when blended with vinyl chloride resin, but zinc chloride, which immediately reacts with hydrochloric acid generated by the thermal decomposition of vinyl chloride resin, causes decomposition of the vinyl chloride resin. Has a promoting feature. On the other hand, calcium compounds generally tend to cause yellow to light brown initial coloring when heated alone when blended with vinyl chloride resin, but the continuous thermal stabilization of vinyl chloride resin has relatively good characteristics. I have.

In the case of a calcium-zinc heat stabilizer comprising a mixture of a calcium compound and a zinc compound in the calcium-zinc heat stabilizer, hydrochloric acid produced by the thermal decomposition of a vinyl chloride resin immediately converts the hydrochloric acid to a zinc compound such as stearic acid. Reacts with zinc and is trapped as zinc chloride.At the same time, the growth of the polyene produced by the dehydrochlorination of the vinyl chloride resin is stopped by the binding of stearic acid residues to suppress color development. For example, it reacts with calcium stearate to form calcium chloride and zinc stearate. Therefore, the calcium-zinc heat stabilizer, while taking advantage of the rapid hydrochloric acid scavenging action of the zinc compound,
It is known that zinc chloride has a remarkable synergistic effect because the effect of promoting thermal decomposition of zinc chloride is eliminated.

The weight ratio of the calcium element to the zinc element in the calcium-zinc heat stabilizer is usually 3/1 to 1/1, preferably 2/1.
/ 1 to 1.5 / 1. If the amount of the zinc compound is excessively small, the molded article obtained by the present invention may take on initial coloring by heating.On the other hand, if the amount of the zinc compound is excessively large, the thermal stability of the molded article may deteriorate and discoloration may occur. Is not preferred. The blending amount of the calcium-zinc heat stabilizer in the present invention is 0.5 to 5 parts by weight, preferably 1 to 4 parts by weight, more preferably 2 to 3.5 parts by weight, per 100 parts by weight of the vinyl chloride resin. If the amount of the calcium-zinc heat stabilizer is excessively small, the molded article obtained by the present invention may cause thermal decomposition by heating. Conversely, if the amount is excessively large, plate-out may occur. It is not preferable.

In the present invention, an oxide or hydroxide of a long-period Group 2 element is blended. Examples of the long-period Group 2 element include beryllium, magnesium, calcium, strontium, barium and the like. Among these, oxides or hydroxides of magnesium and barium are preferred, oxides or hydroxides of magnesium are more preferred, and oxides of magnesium are particularly preferred. The compounding amount of the long-period Group 2 element oxide or hydroxide is 0.1 to 10 parts by weight per 100 parts by weight of the vinyl chloride resin,
Preferably it is 0.5 to 7 parts by weight, more preferably 2 to 5 parts by weight. If the amount is too small, the effect of preventing discoloration, fading, chalking, etc. of the molded article may be insufficient.On the other hand, if the amount is too large, the melt viscosity of the vinyl chloride resin composition may be insufficient. Is undesirably increased due to an excessive increase in the moldability.

In the present invention, a quinacridone pigment,
Perylene pigments, polyazo condensation pigments, isoindolinone pigments, copper phthalocyanine pigments, cadmium pigments,
By blending at least one pigment selected from the group consisting of titanium white and carbon black,
The design of the molded article can be enhanced to further enhance the wooden texture. The quinacridone pigment is obtained by treating p-phenylenedianthranilic acids with concentrated sulfuric acid, and is a pigment having a yellowish red to reddish purple hue. For example,
Quinacridone red, quinacridone magenta, quinacridone violet and the like. The perylene pigment is obtained by a condensation reaction of perylene-3,4,9,10-tetracarboxylic anhydride and an aromatic primary amine, and has a hue ranging from red to reddish purple and brown, perylene red and perylene orange. , Perylene maroon, perylene vermilion, perylene bordeaux and the like.

The polyazo condensed pigment is obtained by condensing an azo dye in a solvent to have a high molecular weight, and has a hue of a yellow or red pigment, such as polyazo red, polyazo yellow, chromophthal orange, chromophthal red, or chromo red. There is phthal scarlet. Isoindolinone pigments are
It is obtained by a condensation reaction of 4,5,6,7-tetrachloroisoindolinone and an aromatic primary diamine, and its hue ranges from greenish yellow to red and brown, and includes isoindolinone yellow.

The copper phthalocyanine-based pigment is a pigment in which copper is coordinated to a phthalocyanine, and its hue ranges from yellowish green to vivid blue, and includes phthalocyanine green and phthalocyanine blue. The cadmium pigment is a pigment formed of a solid solution containing cadmium sulfide and has a hue range of yellow, red, and maroon, and includes cadmium red, cadmium orange, and cadmium yellow. Titanium white is a white pigment made of titanium dioxide, which has a large hiding power and has an anatase type and a rutile type. Carbon black is a black pigment containing carbon as a main component and containing oxygen, hydrogen, nitrogen and the like, and includes thermal black, acetylene black, channel black, furnace black, lamp black, bone black and the like.

In the present invention, by blending the above-mentioned pigment, the molded article is beautifully colored, and is less likely to be discolored or faded even when used outdoors for a long period of time, and hardly causes chalking.

The amount of the pigment in the present invention is 0.1 to 10 parts by weight, preferably 1 to 5 parts by weight, more preferably 1.5 to 5 parts by weight, per 100 parts by weight of the vinyl chloride resin.
3 parts by weight. If the amount of the pigment is too small,
The molded article may be discolored, faded or chalked. Conversely, an excessively large amount of the pigment is not preferred because the natural woody feeling of the molded article may be impaired.

In the present invention, other known additives can be blended. Specifically, a heat stabilizing aid, a lubricant, an antioxidant, an ultraviolet absorber, a foaming agent, a plasticizer, an antibacterial agent, a fungicide, a flame retardant, an antistatic agent, an impact resistance enhancer, and a filler are appropriately used. Is added.

In the present invention, in addition to the calcium-zinc heat stabilizer, a β-diketone compound, hydrotalcite, an organic phosphite, an organic phosphate, a polyol, an epoxy compound and the like are blended.
Further, the protective power against discoloration, fading, chalking and the like can be further enhanced. Particularly, addition of a β-diketone compound and / or hydrotalcite is preferred.

The β-diketone compound is not particularly limited as long as it has one ketone group between three carbon atoms, and examples thereof include acetylacetone, acetylcyclohexanone, acetylstearoylmethane, 1,3-
Cyclohexanedione, dibenzoylmethane, stearoyltetralone, stearoylbenzoylmethane, dehydroacetic acid, palmitoyltetralone, tribenzoylmethane, 2-benzoylcyclohexanone, 2-benzoylcyclopentanone, benzoyltetralone, 4-methoxybenzoylbenzoylmethane, etc. Can be used. The compounding amount of the β-diketone compound is usually 0.02 to 0.5 part by weight, preferably 0.05 to 0.4 part by weight, more preferably 0.1 to 0.4 part by weight, per 100 parts by weight of the vinyl chloride resin. 3 parts by weight. An excessively large amount of the β-diketone compound is not preferred because the thermal stability of the molded article may decrease.

Hydrotalcite is a double salt composed of hydroxides and carbonates of magnesium and aluminum, and a type in which part of carbonate ions are replaced by perchlorate ions is also effective. The amount of the hydrotalcite is usually 0.3 to 5 parts by weight per 100 parts by weight of the vinyl chloride resin,
Preferably it is 1-3 parts by weight, more preferably 1.5-2 parts by weight.

The organic phosphite is represented by the general formula P (OR
¹ ) (OR ² ) (OR ³ ) or HPO (OR ¹ )
Compounds represented by (OR ² ) and their oligo (glycols, bisphenols, triphenols or polyols). R ¹ , R ² and R ³ are each independently an alkyl group having 1 to 18 carbon atoms, an aryl group or an aralkyl group having an alkyl group having 1 to 12 carbon atoms.
Specifically, triisooctyl phosphite, triisodecyl phosphite, triphenyl phosphite, tribenzyl phosphite, trisnonyl phenyl phosphite, diphenyl isooctyl phosphite, diisodecyl pentaerythritol diphosphite, tetraphenyl dipropylene Glycol diphosphite, poly (dipropylene glycol) phenyl phosphite, distearyl pentaerythritol diphosphite, tri-
2,4-di-t-butylphenyl phosphite and the like can be mentioned. The amount of the organic phosphite is usually 0.2 parts per 100 parts by weight of the vinyl chloride resin.
To 5 parts by weight, preferably 0.5 to 3 parts by weight.

Examples of the organic phosphoric acid ester salts include mono- or di-ester salts of calcium, magnesium, barium or zinc, such as isooctyl phosphate and isotridecyl phosphate. The amount of the organic phosphoric acid ester salt is usually per 100 parts by weight of the vinyl chloride resin,
It is 0.2 to 5 parts by weight, preferably 0.5 to 3 parts by weight. As the polyol, an organic compound having two or more hydroxyl groups in the molecule, pentaerythritol,
Dipentaerythritol, glycerin, mannitol,
Sorbitol, trehalose and these and carboxylic acids,
Examples include a partial ester compound with an amino acid or rosin acid. The amount of the polyol is 10
The amount is usually 0.2 to 5 parts by weight, preferably 0.5 to 3 parts by weight per 0 parts by weight.

As the lubricant, any lubricant usually used for processing vinyl chloride resin can be used. Specific examples of the lubricant include soaps of metals other than calcium and zinc, such as lithium stearate, magnesium stearate, aluminum stearate, barium laurate, and barium ricinoleate; n-butyl stearate, methylhydroxystearate, Fatty acid esters such as polyhydric alcohol fatty acid esters; stearic acid,
Fatty acids such as hydroxystearic acid; amide compounds such as stearoamide, oxystearamide, oleylamide, and ethylenebisstearamide; and waxes such as polyethylene wax and paraffin wax. In particular, it is preferable to add 0.5 to 10 parts by weight of the metal soap per 100 parts by weight of the vinyl chloride resin because the processability is improved. In addition, it is preferable to add 0.1 to 5 parts by weight of polyethylene wax because the processability is further improved and the mechanical strength of the molded product is increased.

In order to obtain a foam molded product,
A thermal decomposition type foaming agent is blended. As the thermal decomposition type foaming agent, a thermal decomposition type organic foaming agent and / or a thermal decomposition type inorganic foaming agent are used. Examples of the former include N, N'-dinitrosopentamethylenetetramine, N, N'-dimethyl-N, N '
-Nitroso compounds such as dinitrosoterephthalamide; azo compounds such as azodicarbonamide, azobisisobutyronitrile, benzenesulfonyl hydrazide, p, p '
And sulfonyl hydrazides such as -oxybis (benzenesulfonyl hydrazide) and toluenesulfonyl hydrazide. Examples of the latter include sodium bicarbonate, ammonium bicarbonate, ammonium carbonate and the like. It is preferable to use one or more selected from the group of the organic or / and inorganic pyrolytic foaming agents. The amount of these pyrolytic foaming agents is usually 0.1 parts by weight per 100 parts by weight of the vinyl chloride resin as the component (A).
To 5 parts by weight, preferably 0.5 to 3 parts by weight.

In the present invention, the (meth) acrylate resin is used to uniformly disperse the wood powder and to exhibit a fine and uniform foam cell structure when the above-mentioned foaming agent is blended. It is preferred to add. (Meta)
The acrylate-based resin preferably contains 60% by weight or more of (meth) acrylate units having an alkyl group having 1 to 8 carbon atoms such as ethyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, and ethyl methacrylate. Is a copolymer with 65 to 90% by weight of another copolymerizable monomer. The (meth) acrylate resin preferably has a specific viscosity at 25 ° C. of a chloroform solution having a concentration of 0.2 g / dl of 1.5 to 4.0, and more preferably 2.0 to 3.0. Is more preferable. The amount of the (meth) acrylate-based resin to be added is generally 1 to 20 parts by weight, preferably 3 to 10 parts by weight, per 100 parts by weight of the vinyl chloride resin.

In order to prepare the vinyl chloride resin composition of the present invention, a vinyl chloride resin, wood flour, a calcium-zinc heat stabilizer, an oxide or hydroxide of a long-period Group 2 element, and various Other compounding agents such as a pigment and a heat stabilization aid are collectively put into a mixer such as a Henschel mixer,
The temperature is raised to 120 to 160 ° C. by high-speed stirring and mixing. During this mixing process, the moisture absorbed by the wood flour is volatilized. By high-speed stirring and mixing, a mixture having a large bulk specific gravity and uniformly dispersing each compounding agent can be obtained. After reaching the above temperature, transfer the mixture to a cooling mixer,
Further, if necessary, a pyrolytic foaming agent is added, and 50
Reduce temperature to ~ 60 ° C. After the temperature of the mixture in the cooling mixer has sufficiently decreased, the mixture is taken out of the cooling mixer in the form of a powder. The powdery mixture taken out can be used as a molding compound as it is, but it is usually preferable to subsequently pelletize it. As a preferable method of pelletizing, for example, a single screw extruder or a twin screw extruder with a vent is used.

Using the vinyl chloride resin composition of the present invention,
There is no particular limitation on a molding method for obtaining a vinyl chloride resin molded article having a woody texture similar to natural wood, and usually molded by an extrusion molding method, a calender roll molding method, an injection molding method, a vacuum molding method, or the like. be able to. Thus,
Deck materials, window frames, door frames, wainscots, skirting boards, handrails, and other building materials, fittings, table tops, door stops, etc. that are not prone to discoloration, fading, or chalking even if exposed to sunlight for a long period of time Furniture and the like can be obtained.

[0030]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, which should not be construed as limiting the present invention. In Examples and Comparative Examples, parts and% are based on weight. The color fastness and the degree of chalking were evaluated by the following methods. (1) Color Fastness Evaluated according to JIS K 7102. That is,
A sheet molded from a vinyl chloride resin composition is 60 mm ×
A specimen cut to 120 mm was used as a test piece, and was subjected to water spraying under a condition of spraying water using a sunshine carbon arc lamp type weather resistance tester [Due cycle sunshine weather meter WEL-SUN-DC, Suga Test Machine Co., Ltd.].
Irradiation was performed for 00 hours, and a color computer [SM-4-2, manufactured by Suga Test Instruments Co., Ltd.] was obtained for the test pieces before and after irradiation.
Was used to measure the color difference ΔE. If the degree of color difference is 5 or less, it can be seen that there is almost no discoloration or fading.

(2) Degree of Chalking The test pieces for which the color fastness was examined were evaluated for the degree of choking according to the following criteria. A: No choking at all. ：: Slight chalking. Δ: fairly choking. ×: There is significant choking.

Example 1 100 parts of vinyl chloride resin, 50 parts of wood flour, 4 parts of calcium-zinc heat stabilizer (2 parts of calcium stearate, 2 parts of zinc stearate), 2 parts of magnesium oxide, 0.1 part of dibenzoylmethane , 0.5 parts of hydrotalcite, 2 parts of methacrylic acid ester resin, 1 part of polyhydric alcohol fatty acid ester, 0.2 parts of polyethylene wax, 5 parts of calcium carbonate and 4 parts of quinacridone red are charged into a Henschel mixer and mixed. Water vapor was stripped off. After the temperature rose to 140 ° C., the mixture was transferred to a cooling mixer and cooled while further mixing to obtain a powdery mixture. The obtained powdery mixture was transferred to a cylinder having a cylinder diameter of 6.
Pelletization was performed using a 5 mm vented single screw extruder under the following conditions. In addition, the moisture remaining in the wood powder was volatilized from the vent hole. Screw: L / D = 24, compression ratio 2.5, rotation speed 30
rpm Set temperature: cylinder 145 ° C., head 160 ° C., die 160 ° C. Dice: diameter 3 mm × 12 holes Land length: 10 mm The obtained pellets are 160 ° C. using an 8-inch roll.
For 5 minutes to form a 1 mm thick sheet.
It was pressed at 5 ° C. for 5 minutes to obtain a red sheet rich in woody texture with a thickness of 1 mm. For the obtained sheet, 2,000
A 0 hour accelerated weathering test was performed. The color difference ΔE after the accelerated weathering test was 2.5, and no choking was observed.

Examples 2 to 5 A sheet having a thickness of 1 mm was prepared from the composition having the composition shown in Table 1 in the same manner as in Example 1, and an accelerated weathering test was conducted for 2,000 hours. The subsequent color difference ΔE and the degree of choking were determined. Table 1 shows the results. The notes in the table are the same as in Example 1.

[0034]

[Table 1]

Note * 1: ZEST 700L, Shin-Daiichi Vinyl Co., Ltd., vinyl chloride homopolymer, average degree of polymerization 680. * 2: Sellund, Shimada Shokai, average particle size 80μ
m, water content 5% by weight. * 3: E60-T5-3, manufactured by Misawa Techno Co., titanium oxide particles 5% adhered, average particle diameter 60 μm, water content 5%. * 4: DHT-6, manufactured by Kyowa Chemical Industry Co., Ltd., synthetic hydrotalcite, _{Mg 4. 5} Al ₂ (OH) ₁₃ CO _3.
3.5H ₂ O, average particle size 0.5 μm. * 5: Hybrene B403, a copolymer having about 90% by weight of methyl methacrylate units, manufactured by Zeon Corporation, specific viscosity 2.06. * 6: Roxyl VPN963, manufactured by Cognis Japan, polyhydric alcohol fatty acid ester. * 7: ACPE # 6A, manufactured by Allied Chemical Company, polyethylene wax. * 8: MSKP, manufactured by Maruo Calcium Co., Ltd.
2 μm.

Examples 6 to 10 In the same manner as in Example 1, a sheet having a thickness of 1 mm was prepared from the composition having the composition shown in Table 2, and an accelerated weathering test was performed for 2,000 hours. And the degree of choking were determined. Table 2 shows the results. The notes in the table are the same as in Example 1.

[0037]

[Table 2]

Examples 11 to 15 A sheet having a thickness of 1 mm was prepared from the composition having the composition shown in Table 3 in the same manner as in Example 1, and an accelerated weathering test was performed for 2,000 hours. And the degree of choking were determined. Table 3 shows the results. The notes in the table are the same as in Example 1.

[0039]

[Table 3]

Examples 16 to 21 In the same manner as in Example 1, a sheet having a thickness of 1 mm was prepared from the composition having the composition shown in Table 4, and an accelerated weathering test was performed for 2,000 hours. And the degree of choking were determined. Table 4 shows the results. The notes in the table are the same as in Example 1.

[0041]

[Table 4]

Comparative Examples 1 to 5 A sheet having a thickness of 1 mm was prepared from the composition having the composition shown in Table 5 in the same manner as in Example 1, and an accelerated weathering test was performed for 2,000 hours. The subsequent color difference ΔE and the degree of choking were determined. Table 5 shows the results. The notes in the table are the same as in Example 1.

[0043]

[Table 5]

As shown in Tables 1 to 4, a molded article obtained by adding magnesium oxide, magnesium hydroxide or barium oxide to a vinyl chloride resin composition containing wood flour, together with a calcium-zinc heat stabilizer, There was almost no discoloration and no fading, and no chalking occurred (Examples 1 to 21). When the quinacridone pigment, the perylene pigment, the polyazo condensed pigment, the isoindolinone pigment, the copper phthalocyanine pigment, the cadmium pigment, the titanium white and the carbon black are individually blended, Examples 1 to 1
5) In a case where a plurality of types are used in combination (Examples 16 to 19), the weather resistance was particularly good. On the other hand, all the molded articles of the composition in which cadmium oxide was blended in place of the long-period Group 2 element exhibited deterioration phenomena such as chalking (Comparative Examples 1 to 5).
3). On the other hand, if the amount of magnesium oxide is too small, the choking of the vinyl chloride resin composition becomes remarkable (Comparative Example 4), and if it is too large, the surface condition of the sheet becomes poor due to an increase in melt viscosity (Comparative Example 5). .

[0045]

As described above, according to the present invention, there is provided a vinyl chloride resin composition having excellent woody feeling and hardly causing discoloration, fading or chalking even when irradiated with ultraviolet rays for a long time, and a molded article thereof. .

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08L 97/02 C08L 97/02 F-term (Reference) 4F071 AA24 AA73 AB03 AB18 AC09 AE09 AF57 AH08 BA01 BB03 BC01 4J002 AH00X BD03W BD04W BD05W BD06W BD07W BD08W BD09W DA038 DE077 DE087 DE097 DE138 EG036 EG046 EG076 EG086 EW066 FD060 FD066 FD098 FD170 FD320 GL00 GL01

Claims (4)

[Claims] 1. A vinyl chloride resin composition comprising at least a vinyl chloride resin, wood flour, a calcium-zinc heat stabilizer, and a compound of a long-period Group 2 element, wherein the vinyl chloride resin is 100 parts by weight. The content of each component is as follows: wood flour: 5-150 parts by weight, calcium-zinc heat stabilizer: 0.5-5 parts by weight, oxide or hydroxide of long-period Group 2 element: 0.1- 10
Parts by weight of a vinyl chloride resin composition. 2. With respect to 100 parts by weight of a vinyl chloride resin,
0.1 to 10 pigments selected from the group consisting of quinacridone pigments, perylene pigments, polyazo condensation pigments, isoindolinone pigments, copper phthalocyanine pigments, cadmium pigments, titanium white and carbon black The vinyl chloride resin composition according to claim 1, which contains parts by weight. 3. The vinyl chloride resin composition according to claim 1, wherein the long-period Group 2 element is magnesium. 4. A molded article obtained by molding the vinyl chloride resin composition according to claim 1.