Manufacture of composite film having water proofing property and air permeability

Abstract

Abstract PURPOSE:To obtain a composite film having an excellent stretching property, air permeability and water proofing property by fixing a specific foamed film on a stretching fabric or non-woven fabric, after that, drawing it in the stretching direction of the stretching fabric or non-woven fabric. CONSTITUTION:A foamed film is formed of a composition consisting of 35-65wt.% of ethylene-propylene-diene copolymer A 30-55wt.% of ethylene-vinyl acetate copolymer B, 1-10wt.% of linear low density polyethylene C and 0.1-1.0 pts.wt. of foaming agent D relative to A+B+C 100 pts.wt., and the foamed film and the stretching fabric or non-woven fabric 2 are hot pressed of adhering both of them. Afterwards fine communicating holes 4 are formed in the foamed film by drawing it in the stretching direction of the stretching fabric or non- woven fabric 2. At this time, stretching is carried out in the range of 1.2-2 times, so that fracture occurs on the wall between the fine cells 3 of the foamed film and they connect mutually, and thus, fine communicating holes 4 are formed. Air flows through the communicating holes 4, air permeability is given, however, since the diameter of the fine cells 3 are extremely small, the communicating holes 4 can prevent the current of water.

Inventors

• 👤 Seiji Kagawa
• 👤 清二 加川

Bibliographic Details