Patent ID: 9254607
Filing Date: 2016-02-09
CPC Classification: B29C,B29K,C08J,C08K,Y10T

Claim Text:
1. A method of producing a moisture-permeable and waterproof film, the method comprising the steps of: providing a film comprising polylactic acid and an inorganic filler, wherein the polylactic acid has a melting point of 150° C. to 170° C.; then preheating the film comprising the polyactic acid and inorganic filler at a temperature of 40° C. or higher and below a glass transition temperature of the polylactic acid; and stretching the film by wherein said stretching further form, in the film, projections and recesses alternatingly arranged in the machine direction from the plurality of teeth, the high-stretch regions correspond to regions which undergo essentially stretching of the film and in which the film does not contact tip sections of the plurality of teeth, the low-stretch regions correspond to regions which undergo essentially no stretching of the film and in which the film contact the tip sections of the plurality of teeth, and the film has bending resistance in the range of 15-30 mm, and moisture permeability in the range of 2,000-4,000 g/m