JPH0739515B2 - Matte molding material composition - Google Patents

Description

TECHNICAL FIELD The present invention relates to a matte molding material composition having a matte effect on the surface of a molded article by a thermoplastic resin composed of polyethylene, polypropylene or polystyrene, and particularly to a moldability or The present invention relates to a matte molding material composition capable of producing a matte effect on the surface of a molded product without impairing the physical properties of the molded product.

[Prior Art] When molding a molded product by injection molding, extrusion molding or the like using a thermoplastic resin, in order to change the texture of the molded product or to give a feeling of weight or luxury, for example, a piano, an electric tone, etc. Matte treatment may be applied to the surface of keyboards, molded products such as televisions and office automation equipment.

As the above-mentioned delustering treatment, a method of embossing the surface of a mold or a calendar roll to form a fine pattern on the surface of the molded article has been conventionally used.

There has also been an attempt to mix an inorganic filler such as calcium carbonate or talc into a thermoplastic resin so that the resin itself has a matting effect.

[Problems to be solved by the invention]

However, the former method has the drawbacks that the cost of engraving a pattern on the surface of a mold, a calendar roll, etc. is high, and that it is difficult to make fine joints.

In the latter method, the matting effect of the above-mentioned inorganic filler is small, so that the blending ratio becomes high, which results in deterioration of the physical properties and moldability of the obtained molded product, resulting in poor practicability.

Therefore, the present inventor has conducted extensive studies to improve the above-mentioned drawbacks, and by selecting a calcium oxide powder having a specific particle size as a matting material, it is possible to achieve an excellent matting effect with a small amount of compounding, Therefore, they have found that a matting effect can be achieved without deteriorating the physical properties and moldability of the obtained molded product, and completed the present invention.

An object of the present invention is to provide a matting molding material composition which can exert a matting effect on the surface of a molded product without impairing moldability or physical properties of the molded product, and which has improved the above-mentioned drawbacks in the known art. .

[Means for solving problems]

In order to achieve the above-mentioned object, according to the present invention, in a matting molding material composition comprising a calcium oxide powder mixed with a thermoplastic resin composed of polyethylene, polypropylene or polystyrene, the calcium oxide powder has a particle size of 300μ. It is characterized in that the content is 0.5 to 30% by weight.

The thermoplastic resin used in the present invention is polyethylene, polypropylene or polystyrene.

When the particle size of calcium oxide is larger than 300μ, coarse particles are conspicuous and the surface of the molded product is roughened, and the matting effect is small, and when the compounding amount is 0.5% by weight or less, the matting effect does not appear and %, The physical properties and moldability of the obtained molded product are deteriorated. Therefore, the calcium oxide suitable for the present invention has a particle size of 300 μ or less, preferably 100 μ or less, and a compounding amount of 0.5 to 30% by weight, preferably 1 to 10% by weight. %.

Since the above-mentioned calcium oxide has high reactivity with water, it is particularly preferable that the calcium oxide is surface-treated with a silane coupling agent, an oil agent, liquid paraffin or the like in view of its handling.

Further, in the present invention, known colorants, stabilizers, dispersants and the like can be added in appropriate amounts in addition to the above-mentioned calcium oxide.

The above-mentioned composition of the present invention is mixed with a two-roll mill or the like and used as a molding material for injection molding, extrusion molding or the like to obtain a molded article having a matt surface.

[Action]

In the above-mentioned molding material composition of the present invention, since the particle size of calcium oxide used is small particles of 300 μ or less, the roughness of the surface of the molded product is prevented and the matting effect is increased, and the compounding amount is 0.5 to 30. Since it is a small amount by weight, the moldability is good, and the physical properties of the molded product are not deteriorated.

〔Example〕

 Hereinafter, the present invention will be described in detail with reference to examples.

Example-1 (1) High-density polyethylene (Hi-Zex 2100J manufactured by Mitsui Petrochemical Industry Co., Ltd.) was crushed to a particle size of 74 μm or less (20
30 wt% calcium oxide adjusted to 0 mesh pass)
Was mixed on two rolls with a roll temperature of 180 ° C., formed into a sheet, and then pelletized into square pellets with a square pelletizer.

(2) Next, low density polyethylene (Novatech LF261
30% by weight of Furness Black (Mitsubishi Carbon ^# 40B, manufactured by Mitsubishi Kasei Co., Ltd.) is mixed and dispersed in 1.7 test banbury to make a sheet with two rolls and then made into square pellets with a square pelletizer. Got

(3) Blend 2% by weight of the carbon masterbatch prepared in (2) to the pellet of (1), and measure 6.5cm × 5cm × 0.2c
A test piece of m was prepared by injection molding.

Example-2 As a molding pellet of Example-1, HiZex 2100
Same as J except that 33.33% by weight of pellets containing 30% by weight of calcium oxide obtained in Example-1 (1) and 2% by weight of the carbon masterbatch prepared in Example-1 (2) were blended in J A test piece was obtained.

Example-3 In Example-2, as calcium oxide, it was crushed and the particle size was
A test piece was obtained in the same manner except that calcium oxide having a particle size of 300 μ or less (50 mesh pass) was used.

Example-4 A test piece was obtained in the same manner as in Example-2, except that polypropylene (Sumitomo Noblen AH-561 manufactured by Sumitomo Chemical Co., Ltd.) was used instead of Hi-Zex 2100J in Examples-1 and-2.

Example-5 A test piece was obtained in the same manner as in Example-2, except that HI polystyrene (manufactured by Dialex HT-88 Mitsubishi Monsanto Kasei Co., Ltd.) was used instead of Hi-Zex 2100J in Example-1 and Example-2. .

Example-6 A test piece was obtained in the same manner as in Example-2 except that the pellet obtained in Example-1 (1) was changed to 10% by weight.

Example-7 A test piece was obtained in the same manner as in Example-2, except that the amount of the pellet obtained in Example-1 (1) was 2% by weight.

Comparative Example-1 Hi-Zex 2100J was blended with 2% by weight of the carbon masterbatch prepared in Example-1 (2), and a test piece was obtained by injection molding.

Comparative Example-2 In Comparative Example-1, HiZex 2100J was added to Sumitomo Noblen AH-5.
A test piece was obtained in the same manner except that 61 was replaced.

Comparative Example-3 Hi-Zex 2100J was used in Comparative Example-1 and Dialex HT-8
A test piece was obtained in the same manner except that it was replaced with 8.

Comparative Example-4 A test piece was obtained in the same manner as in Comparative Example-1, except that Hi-Zex 2100J was replaced with Clarastic SHF.

Comparative Example-5 A test piece was obtained in the same manner as in Example-2 except that the pellet obtained in Example-1 (1) was changed to 1%.

Comparative Example-6 In Example-2, calcium oxide was pulverized to give a particle size of 300.
A test piece was obtained in the same manner except that calcium oxide having a size of μ or more (50 mesh on) was used.

Comparative Example-7 A test piece was obtained in the same manner as in Example-2 except that calcium carbonate (Mamacarso Nitto Koka Kogyo Co., Ltd.) was used instead of calcium oxide.

Comparative Example-8 In Example-2, talc (talc) was used instead of calcium oxide.
A test piece was obtained in the same manner except that MS Shiraishi Calcium Industry Co., Ltd.) was used.

With respect to the above test pieces, the appearance (image) of the light source (fluorescent lamp) and the presence / absence of gloss were visually evaluated in five levels.

The results are shown in Table-1.

It can be seen from Table 1 that if the calcium oxide has a specific particle size of the present invention or less, the appearance of the molded article is not impaired and a matting effect is obtained with a low compounding amount. It is also superior to other fillers and its characteristics are clear.

In addition, in the above-mentioned examples, all have good moldability,
The physical properties of the obtained sample were not deteriorated.

〔effect〕

As described above, since the molding material composition of the present invention uses a specific small amount of calcium oxide powder having a particle size of 300 μ or less, the moldability is good, the matting effect is excellent, and the physical properties are not deteriorated.

Claims (1)

[Claims] 1. A matting molding material composition comprising a thermoplastic resin made of polyethylene, polypropylene or polystyrene, and calcium oxide powder blended therein, wherein the calcium oxide powder has a particle size of 300 μm or less and a blending amount of
Matting molding material composition, characterized in that it is 0.5 to 30% by weight.