| 摘要 |
PROBLEM TO BE SOLVED: To color by a low cost and simple method and eliminate an ununiform coloration by a method wherein a film, which is obtained by melting, extruding and stretching longitudinally a polypropylene-based resin containing a specified percentage of a propylene component, is coated with a colorant-containing coating solution and, after being dried, stretched laterally. SOLUTION: A film, which is obtained by melting, extruding and stretching longitudinally a polypropylene-based resin containing 98 wt.% or more of propylene component, is subjected to a corona treatment and coated with a colorant-containing coating solution and, after being dried, successively stretched laterally. As the preferable coating solution, the solution of various thermoplastic resins such as a polyolefinic resin, an acrylic resin, a polyester-based resin, a polyvinyl chloride or the like or a dispersion is used in order to improve the fixing of the colorant or, when occasion demands, give a printability and gas barrier properties to the film. The coating method of the coating solution is one with a roll coater, a bar coater, a gravure coater, an air knife coater or the like. |
