Polyurethane condom of welded polyurethane film
AssigneePolygenex International, Inc.
InventorTilak M. Shah
Life of this patent
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Abstract
A method of welding at least two layers of a thin thermoplastic polyurethane elastomer (10A, B) to form a weld seam (12) to produce polyurethane barrier products such as, but not limited to, gloves (20), condoms (30), inflatable catheter balloon cuffs (48A, B), ostomy pouches (50), organ bags (60), and instrument covers (70) through a process of pre-heating a sealing die platen, the at least two layers of the polyurethane (10A, B) softened while under pressure from the preheated die platen, followed by welding the at least two layers of polyurethane (10A, B) film by transmission of a radio-frequency energy to the film (10A, B) to produce a weld seam (12) and then allowing the weld seam (12) to cool, the resultant product having seam integrity.
Claims8
A polyurethane condom comprising:
- A. An elongated tubular structure having one open base end and one dosed distal end, said structure being formed of two generally flat sheets of a polyurethane elastomer film having a thickness of from about 0.5 to 5 mils;
- B. A continuous radio frequency weld joining said two sheets along the periphery thereof starting at said open base end and extending axially to the distal end, extending around the periphery of said distal end, and axially from said distal end to said open base end, said weld having an elongated generally U shape, leaving said open end unwelded, such that the facing surfaces of said sheets define the interior of said condom;
- C. Said radiofrequency weld having a width of two to ten times the thickness of said polyurethane film and a bond strength substantially the same as the unwelded film.
Dependencies are inferred from the claim text.