JPS5996151A - Resin composition for obtaining colored polyvinyl chloride molding - Google Patents

Abstract

PURPOSE:To provide the titled resin compsn. which gives colored moldings having excellent appearance without causing any depositions of foreign matters on dies during molding, by blending a polysiloxane-treated inorg. pigment as a colorant. CONSTITUTION:0.1-10pts.wt. heat-curable (or catalyst-curable) polysiloxane such as methylhydrogenpolysiloxane and a dispersion aid such as polyethylene wax are added to 100pts.wt. inorg. pigment such as titanium dioxide, red iron oxide or carbon black, and the mixture is kneaded to obtain a colorant composed of the polysiloxane-treated inorg. pigment. The colorant is blended with a rigid polyvinyl chloride compound [a compsn. consisting of vinyl chloride (co)polymer having an average degree of polymn. of 700-1,300, a lead salt stabilizer, a lubricant, etc.].

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a resin composition for colored extrusion molding or injection molding of hard polyvinyl chloride resin.

Conventionally, hard polyvinyl chloride resin has been colored and molded with various organic and inorganic pigments to produce various molded products such as rain gutters and pipes.

However, when extrusion or injection molding is carried out using hard PVC compounds containing lead-based stabilizers, especially inorganic pigments as colorants, some of the molding screws, cylinders, etc. part, breaker
Foreign matter accumulates in the plate section, nozzle section, and die section. This foreign matter was then discharged onto the surface of the polyvinyl chloride molded product, significantly impairing the appearance of the resulting molded product.

The inventors of the present invention have carried out various studies to solve these conventional drawbacks, and have found that by using an inorganic pigment that has been particularly treated with polysiloxane as a coloring agent for polyvinyl chloride, it has been found that The present invention was achieved based on the finding that no foreign matter adheres.

That is, the present invention provides a colored molding resin composition in which a coloring agent is blended with a hard polyvinyl chloride compound containing a lead-based stabilizer, in which an inorganic pigment treated with a heat-curable or catalyst-curable polysiloxane is used as the colorant. The present invention relates to a polyvinyl chloride colored molding resin composition characterized in that it is used.

The hard vinyl chloride compound used in the present invention is a vinyl chloride resin alone or a copolymer of styrene, ethyl acrylate, methyl acrylate, methyl methacrylate, acrylonitrile, acrylamide, vinyl acetate, etc. with an average degree of polymerization of 700 to 130 degrees, and a lead salt-based compound. stabilizer,
Contains lubricants such as metal soap stabilizers, calcium carbonate, and stearic acid.

The polysiloxane used in the present invention is a polysiloxane that forms a hydrophobic film by being cured by heating and/or a suitable catalyst, such as methylhydrodiene polysiloxane, ethylhydrodiene polysiloxane, etc. Particularly effective are alkylhydride tetradiene polysiloxanes, organopolysiloxanes containing reactive groups such as vinyl groups and epoxy groups, and the most preferred is methylhydrodiene polysiloxane.

Preferably, such polysiloxanes are used in an amount of about 0.1 to 10.0 parts by weight per 100 parts by weight of inorganic pigment.

In the present invention, examples of the inorganic pigments treated with the polysiloxane include titanium dioxide pigments, titanium yellow pigments,
Examples include cobalt blue pigment, red iron, yellow lead, and carbon black.

The inorganic pigment may be treated directly with the polysiloxane according to a conventional method, but when dispersing the inorganic pigment in polyvinyl chloride resin, a resinous dispersion aid may be used. Dispersion aids include low molecular weight polyethylene, low molecular weight polypropylene, and polybutene.
1. An ethylene-vinyl acetate copolymer and a mixture thereof, which improves the dispersibility of the pigment in the polyvinyl chloride resin, and the amount used is about 5 to 100 parts by weight of the pigment. Preferably, it is used in a proportion of 50 parts by weight.

Furthermore, in the present invention, when the inorganic pigment is treated with polysiloxane, in addition to the resinous dispersion aid described above, aids such as metal stearate, calcium carbonate, magnesium carbonate, clay, zinc white, etc. are used. Ru.

The colorant used to obtain the polyvinyl chloride colored molding resin composition of the present invention may be in any form, but is most preferably a powder type, for example, a predetermined amount of pigment, polysiloxane and dispersion. After mixing the auxiliary agent with a mixer with strong shearing force (heated mixing roll, etc.), it is cooled and
Grind to obtain powdered colorant.

Then, in order to obtain the polyvinyl chloride colored molding resin composition according to the present invention by blending the coloring agent into a polyvinyl chloride resin compound, the powder coloring agent is blended into the polyvinyl chloride resin compound, and this is then mixed at high speed. This is accomplished by mixing at room temperature using a mixer (for example, Nisper Mixer (trade name, manufactured by Kakuda Seisakusho)).

When the polyvinyl chloride colored resin composition for molding of the present invention obtained as described above is used as a material for extrusion molding or injection molding according to a conventionally known method, the screw of the molding machine can be used even after long continuous molding operations. No accumulation of foreign matter was observed in some parts of the cylinder, breaker plate, nozzle, die, etc., and a colored polyvinyl chloride molded product with an excellent appearance was obtained. Furthermore, since the processing agent used in the present invention is used in a relatively small amount, the various other performances of the inorganic pigment are not impaired at all, and the processing agent does not deteriorate the physical properties of the polyvinyl chloride resin.

Next, the present invention will be specifically explained with reference to Examples.

Note that parts in the text refer to parts by weight.

Example 1 Polyethylene wax (product name: Sunwax 151P
27.5 parts of Sanyo Chemical Co., Ltd. product), 70 parts of titanium dioxide, 2.5 parts of silicone oil KF99 (product name of Shin-Etsu Chemical Co., Ltd.), 11 parts of silicone oil KF99
The mixture was mixed three times with three heated rolls at 0° C., then cooled and pulverized to obtain a white coloring agent. 2 parts of this coloring agent were mixed with 100 parts of a polyvinyl chloride compound of the following composition prepared separately, and this was further placed in a high-speed mixer (product name: J Super Mixer Gogo Manufacturing Co., Ltd.) and mixed for 3 minutes at room temperature to form a polyvinyl chloride compound. A resin composition for colored vinyl chloride molding was obtained.

[Polyvinyl chloride compound composition]

Polyvinyl chloride resin 100 parts (average degree of polymerization 800) Lead stearate 1.5 parts Tribase
2 parts dibasic lead phosphite
1 part dibasic lead stearate 1 part calcium carbonate 5 parts stearic acid
0.5 parts Example 2 70 parts of yellow lead, 22 parts of calcium stearate, 3 parts of calcium carbonate, and 5 parts of methylhydrodiene polysiloxane (trade name: Silicone Oil KF 99, product of Shin-Etsu Chemical Co., Ltd.) were mixed in a high-speed mixer (trade name: The mixture was mixed and ground for 10 minutes using a Henschel mixer (manufactured by Mitsui Miike Seisakusho) to obtain a yellow coloring agent. 1.5 parts of this coloring agent was blended with 100 parts of a separately prepared polyvinyl chloride compound having the following composition, and this was further placed in a high-speed mixer (trade name: Super Mixer Yoda Seisakusho product) and mixed for 3 minutes at room temperature. A polyvinyl chloride colored molding resin composition was obtained.

[Polyvinyl chloride compound composition]

Polyvinyl chloride resin 90 parts (average degree of polymerization 800) Acrylic modifier 10 parts (product name;
Paraloid KM323 (Om & Haas product) Lead stearate 2 parts tribase
3-part dibasic lead phosphite
1.5 parts calcium carbonate
10 parts Example 3 Polyethylene wax (product name: Sunwax 151P
; Sanyo Chemical Co. product) 18 parts, polyethylene wax (product name: Hiwax Mitsui Petrochemical Co. product) 13.
5 parts, red iron oxide, 50 parts, calcium carbonate, 15 parts, and 3.5 parts of methylhydrodiene polysiloxane (trade name: Silicon SH1107, a product of Toray Silicon Co., Ltd.) at 110°C.
The mixture was mixed three times with three heated rolls, cooled, and crushed to obtain a brown coloring agent. Two parts of this colorant were blended with 100 parts of the same polyvinyl chloride compound used in Example 1, and a colored polyvinyl chloride molding resin composition was obtained in the same manner as in Example 1.

Comparative Example 1 Polyethylene wax (product name: Sunwax 151P
, a product of Sanyo Chemical Co., Ltd.) and 70 parts of titanium dioxide were blended with 30 parts of titanium dioxide, mixed three times with a heated triple roll at 110° C., cooled, and crushed to obtain a white colorant. Using this colorant, a colored polyvinyl chloride molding resin composition was obtained in the same manner as in Example 1 except for the above.

Comparative Example 2 70 parts of yellow lead, 20 parts of calcium stearate, and 10 parts of calcium carbonate were mixed and pulverized for 10 minutes using a high-speed mixer (trade name: Henschel mixer manufactured by Mitsui Miike Seisakusho) to obtain a yellow colorant. Using this colorant, the others were Example 2.
A polyvinyl chloride colored molding resin composition was obtained in the same manner as above.

Usage Examples The polyvinyl chloride colored molding resin compositions obtained in Examples 1 to 3 and Comparative Examples 1 to 2 were each 30 mm and 12 rL = 2
temperature condition C1 = 160°C, c
2=iso℃, C3=190℃, die part 180℃ 2
Continuous extrusion was carried out for 4 hours to form a tube with a diameter of 8 mm 2 /l, and the state of adhesion of foreign matter on the screw tip, the maker plate, and the die surface was observed. The results are shown in Table 1.

Chapter - Table

Claims (2)

[Claims] (1) In a colored molding resin composition in which a colorant is blended with a hard polyvinyl chloride compound containing a lead-based stabilizer, an inorganic pigment treated with heat-curable or catalyst-curable polysiloxane is used as the colorant. A polyvinyl chloride colored molding resin composition characterized by: (2) The colored polyvinyl chloride molding resin composition according to claim 1, wherein the polysiloxane is methylhydrodiene polysiloxane.