摘要 |
PURPOSE:To form a cellular film having high moisture and air permeability by coating the surface of a substrate with a solution of a resin containing an amino acid and a solution containing a phase separation nucleating agent in an organic solvent, drying the coated substrate and causing phase separation. CONSTITUTION:A solution of a phase separation nucleating agent (preferred example; urea) in an organic solvent of N,N-dimethylformamide is added to a solution of a polyamino acid component, such as poly-gamma-methyl-L-glutamate, as a typical example in dimethylformamide and the obtained mixture is homogeneously mixed. The resultant blended solution is then applied to a polyester- based synthetic resin film and subsequently dried to cause phase separation. Thereby, a cellular film having high moisture and air permeability is formed. |