PREPARATION FOR POLYESTER FILM,申请号JP19820175975-传众专利搜索

PREPARATION FOR POLYESTER FILM

申请公布号：JPS5967018(A)

申请号：JP19820175975

申请日期：1982.10.06

申请公布日期：1984.04.16

申请人：

DAIAFOIL KK

发明人：UCHIUMI SHIGEO;KANEZAKI TAKEO

分类号：B29C49/00;B29C55/00;B29C55/14;C08J5/18

主分类号：B29C49/00

摘要：PURPOSE:To contrive to raise productivity by increasing the ratio of stretching by such an arrangement wherein after a film which is prepared by melting and extruding polyester is stretched in one axial direction, it is further stretched by the second stage of operation at higher temperature, and next, it is stretched in the direction perpendicular to the previous direction and then fixed. CONSTITUTION:An amorphous non-stretched film is prepared by melting and extruding polyester containing less than 0.10wt% of infusible particles, and this film is stretched by the first stage in one axial direction until its double refractive index becomes 15X10<-3>-30X10<-3> and then it is heat-treated at such temperature higher than that of the first stage stretching so that its degree of crystallization becomes 2-15%, and after that it is further stretched by the second stage in the same direction as previous one until its double refractive index becomes higher than 80X10<-3>, and after that, it is stretched in the direction perpendicular to the previous direction and it is thermally fixed. Thermal fixation is normally carried out at 180-245 deg.C, and by this, stretching distortion of the film is removed and crystallization progresses. Thereby, it becomes possible to form a smooth film from polyeser which substantially doesn't contain infusible particles. Since projections of this film are composed of polyester itself, the film is excellent in wear resistibility.