| 摘要 |
PURPOSE: To obtain a porous film or sheet which does not allow cracks, uneveness, etc., to occur, has uniform pore sizes, and is gas- and liq.-permeable by stretching a resin contg. a specific precipitated calcium carbonate. CONSTITUTION: This film or sheet is obtd. by stretching a resin (e.g. a polyolefin) contg. a precipitated calcium carbonate which contains at least 50wt.% particles with particle sizes of 0.5-3μm and has a max. particle size of 8μm or smaller, an average ratio of L/D (wherein L is the major axis of the particle; and D is the minor axis) of 1.6 or smaller, and a specific surface area of 15m<2> /g or smaller. |
