Tracy E Wilson

US Patent:

61799394, Jan 30, 2001

Filed:

May 12, 1997

Appl. No.:

8/854460

Inventors:

Billy Ray Jones - Cumming GA
Rob Lee Jacobs - Woodstock GA
Tracy Neal Wilson - Woodstock GA

Assignee:

Kimberly-Clark Worldwide, Inc. - Neenah WI

International Classification:

B29C 5506
B29C 6508
B29C 6720

US Classification:

156 731

Abstract:

Breathable barriers, comprising a thermoplastic polymer and at least 30% by weight filler, are stretched in one direction in multiple discrete steps wherein the strain rate of each discrete stretching step is less than about 100,000%/minute and wherein the line speed of the last stretching step is in excess of 500 feet per minute. The resulting films may be stretched, as a result of the cumulative discrete stretching operations, from about 2 to 7 times its original length in order to create a breathable barrier having a WVTR in excess of 800 g/m. sup. 2 /day and a hydrohead of at least 60 cm.