摘要 |
BREATHABLE MICROPOROUS FILM AND A METHOD FOR MAKING IT A method for making soft, flexible, microporous films having high tensile strength and high breathability levels for air and water vapor and high hydrostatic resistance to penetration by liquid water, in which a film fabricated by blending a mixture of a polymer or copolymer of an alphaolefin with 60 to 75% by weight of an inorganic filler or glass beads having particle sizes within the range of 10 to 15 micrometers and calcium stearate as a processing aid is biaxially stretched from about 1.5 to about 7 times in each direction at a temperature of from about 200 to about 160.degree.C, and the moisture level in the blended composition is maintained below 700 parts per million before fabricating the film; the film so made having a Gurley porosity of from 0.1 to 20 seconds; and its use in disposable items such as panty liners, diapers, bed sheets, and hospital gowns, or, if the filler consists of glass beads, its use as a battery separator. |