| 摘要 |
PROBLEM TO BE SOLVED: To provide a water absorptive sheet, which is useful as a packaging material and a covering material, or a sheet-shape gel agent, and has a heat resistance, and can contract by water. SOLUTION: The water absorptive sheet is composed of an intermediate layer of polyalkylene oxide resin and two polyvinyl alcohol resin layers sandwiching the intermediate layer from both sides thereof. Further, the three layers are formed by extrusion molding at the same time, and are treated by the ionizing radiation irradiating treatment. The three layers may be treated by drawing. In addition, the periphery of the upper and lower polyvinyl alcohol resin layers may be stuck by fusion. COPYRIGHT: (C)2004,JPO
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