| 摘要 |
PURPOSE:To produce a synthetic paper excellent in foldability. CONSTITUTION:Apolypropylene-based synthetic paper is produced by compounding 100 pts.wt. crystalline polypropylene resin with 50-200 pts.wt. the sum of 30-180 pts.wt. cyclopentadiene petroleum resin having a softening point (ring and ball method) and 20-170 pts.wt. inorg. filler powder, forming the resulting compsn. into a sheet, stretching the sheet to an areal stretching ratio of 9 or higher to give a stretched sheet with a density of 0.05-0.6g/cm<3>, and thermaly compressing the stretched sheet at 80-160 deg.C under a pressure not making the sheet transparent. |
