Process for microaperaturing and microembossing a polymeric web

Claim 1

A continuous, multi-phase process for perforating and embossing a substantially continuous web of substantially planar polymeric film to form a microapertured and microembossed polymeric web, said process comprising the steps of: (a) continuously supporting said web of film on a first forming structure exhibiting a multiplicity of fine-scale apertures which place the opposed surfaces of said first forming structure in fluid communication with one another, said first forming structure moving in a direction parallel to the direction of travel of said web of film and carrying said web of film in said direction, said first forming structure including a woven wire mesh having a predetermined mesh count; (b) substantially continuously applying a first fluid pressure differential across the thickness of said web of film along said direction of movement of said first forming structure exhibiting said fine-scale apertures, said first fluid pressure differential being sufficiently great to cause said web of film to rupture in those areas coinciding with said fine-scale apertures in said forming structure forming a microapertured web; (c) continuously supporting said microapertured web of film on a second forming structure exhibiting a multiplicity of fine-scale apertures which place the opposed surfaces of said second forming structure in fluid communication with one another, said second forming structure moving in a direction parallel to the direction of travel of said microapertured web of film and carrying said microapertured web of film in said direction, said second forming structure including a woven wire mesh having a predetermined mesh count, said predetermined mesh count of said second forming structure being at least about 20 filaments per square inch less than said predetermined mesh count of said first forming structure; and (d) substantially continuously applying a second fluid pressure differential across the thickness of said microapertured web of film along said direction of movement of said second forming structure, said second fluid pressure differential being sufficiently great to cause said microapertured web of film to be urged into substantial conformance with the fine-scale apertures of said second forming structure to form a pattern of fine-scale microembossments superimposed upon a pattern of fine-scale microapertures, said pattern of fine-scale microembossments having a pattern density of at least about 20 filaments per square inch less than a corresponding pattern density of said pattern of fine-scale microapertures, while substantially maintaining the integrity of said fine-scaleapertures formed by said first fluid pressure differential forming a microapertured and microembossed web of film.