| 摘要 |
PROBLEM TO BE SOLVED: To provide a rigid polyvinyl chloride resin sheet which is free from creases which would otherwise be generated at the time of vacuum molding or air-pressure forming, due to insufficient shrinkage in the width direction following the stretching of the sheet subsequent to the process of sheet shrinkage generated by the heating of a molding machine, in molding the rigid polyvinyl chloride resin sheet into a vessel-like form and its manufacturing method. SOLUTION: This manufacturing method eliminates the generation of creases during vacuum molding or air-pressure forming due to the significant influence of a thermal shrinkage factor in the width direction, with the use of the rigid polyvinyl chloride resin sheet which shows a thermal shrinkage factor in the width direction of -2 to +1 % when the sheet is soaked in an oil bath at 80 to 160°C for 3 to 5 min and further, a thermal shrinkage factor in the flow direction of -4 to -10% when the sheet is soaked in the oil bath at 130°C for 3 to 5 min. COPYRIGHT: (C)2005,JPO&NCIPI |
