| 摘要 |
PURPOSE:To prevent plastic material from whitening by a method wherein synthetic resin film or sheet is kneaded with white pigment during the plastic working of plastic material, which contains at least synthetic resin film or sheet, under pressure without heating. CONSTITUTION:Plastic material concerned contains at least synthetic resin film or sheet. Composite material produced by gluing metallic material such as metallic foil, metallic plate or the like to synthetic resin film or sheet may be acceptable. Film or sheet made of polypropylene, polyethylene or the like is employed as the synthetic resin film or sheet. Said synthetic film or sheet is kneaded with whit pigment. As the white pigment, titanium oxide, zinc white or the like is used. In addition, the preferable amount of the white pigment to be kneaded is about 0.5-2pts.wt. of the pigment to 100pts.wt. of synthetic resin. Thus, even when polymeric chains are oriented and whitened during plastic working, especially stretching, the color of the synthetic film or sheet does not change. |
