| 摘要 |
PROBLEM TO BE SOLVED: To provide a resin molding, which is equipped with various characteristics intrinsic to the resin and excellent in solvent resistance. SOLUTION: The manufacturing method of this resin molding is to produce a compressive stress of 10 kgf/cm<2> or more between arbitrary two points, which locate below the surface of the resin molding by 0.1 mm or less and are parallel to the surface. This resin molding is obtained by heating up to the glass transition temperature of the resin or higher and then cooling down to the temperature lower than the glass transition temperature. As the resin composing this resin molding, publicly known polymer compounds such as polymethyl methacrylate, polystyrene, polycarbonate, polyethylene terephthalate and the like are exampled and especially acryl-based (co)polymer, which is mainly made of a methyl methacrylate unit (or includes 80 wt.% or more of this unit) and excellent in transparency, is suitable. Further, the effective bestowal of surface compressive stress can become possible. |
