The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 14, 1989
Filed:
Apr. 11, 1988
Timothy R Woods, Midland, MI (US);
R Douglas Behr, Midland, MI (US);
The Dow Chemical Company, Midland, MI (US);
Abstract
A process and apparatus is provided for cutting multiple plies of thermoplastic material having thickened sections, such as defined by cross-sections of matable parts of a zipper closure formed in the material, and for concurrently sealing the severed margins of the material which includes sealing the severed zipper closure portions thereof. The process and apparatus perform the operative steps of: first, preblocking the thickened material adjacent to the zipper closure portions of the material in areas thereof to be severed and sealed; then, applying heat and pressure to the thickened material and remaining sections of the material in those areas to render the material tacky and temporarily stick the multiple plies together in those areas; and, thereafter, contacting those areas of the material with a heated cutting and sealing element in order to sever all of the multiple plies and seal the severed margins thereof. Further, after the application of heat and pressure, the zipper closure portions of the material in the areas thereof to be severed and sealed are preheated. Also, after the margins of the multiple plies of material are severed and sealed, pressure is applied to the zipper closure portions at the severed and sealed margins to ensuring sealing thereof.