| 摘要 |
PROBLEM TO BE SOLVED: To reduce light transmittance with little pigment, to raise a strength and to optimize for a perfecting printing by sheet molding resin containing dark color pigment and having specific light transmittance and resin containing tint pigment by coextrusion. SOLUTION: Resin containing dark color pigment and having 1% or less of light transmittance and resin containing tint pigment are sheet molded by coextrusion. The dark color pigment is generally carbon. The resin mixed with the dark color resin is normally polyolefin such as polyethylene or polypropylene. The tint pigment is generally titanium white. As the resin, the same type as the resin mixed with the dark color pigment is preferable to eliminate adhesive properties and a difference of expansion or contraction due to heat to coextrude it. And, the sheet has a thickness of about 0.1 to 3.0mm. Dark color sheet may have a thickness of about 1 to 20% of the entirety. A product of the coextruded sheet 1 is obtained, for example, by sandwiching a resin layer 2 containing the dark color pigment between resin layers 3 each containing the tint pigment. |
