| 摘要 |
SUBSTANTIALLY FLUID-IMPERVIOUS MICROBUBBLED POLYMERIC WEB EXHIBITING LOW LEVELS OF NOISE WHEN SUBJECTED TO MOVEMENT A microbubbled, substantially fluid-impervious polymeric web exhibiting substantially the same consumer preferred soft and cloth-like tactile impression and low noise generation levels heretofore only achievable in microapertured, and hence substantially fluid pervious, polymeric webs. In a particularly preferred embodiment, the present invention pertains to a microbubbled polymeric web exhibiting a fine-scale pattern of discrete mushroom-shaped surface aberrations, each of said surface aberrations having its amplitude oriented substantially perpendicular to the surface in which the surface aberration originates. However, unlike microapertured webs which are fluid pervious, at least one tiny, continuous membrane bubble, i.e., a microbubble, is provided substantially coincidental with the maximum amplitude of each surface aberration. Thus, the microbubbled web is substantially fluid-impervious. In addition, such a web employing the fine-scale pattern of microbubbled surface aberrations does not exhibit the "rattling" or "rustling" noises typically exhibited by prior art fluid-impervious polymeric webs when subjected to movement. As a result, webs of the present invention have particular utility in environments such as substantially fluid-impervious backsheets for disposable infant diapers and adult incontinent diapers. Preferred method and apparatus for producing microbubbled webs either in "planar" or "macroscopically expanded" form are also disclosed. |
