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:
Dec. 22, 1998
Filed:
Nov. 07, 1997
Joseph Arthur LaRose, Ravenna, OH (US);
Eric Alan Overholt, Bath, PA (US);
Lawrence Joseph Schnieders, Eastlake, OH (US);
Avery Dennison Corporation, Pasadena, CA (US);
Abstract
The present invention relates to a process for producing a polymer film from an aqueous polymer composition wherein the process comprises the steps of: (A) introducing an aqueous composition comprising water and a polymer through at least one feed unit in one or more upstream sections of an extruder comprising a plurality of interconnecting sections wherein at least one downstream section comprises a homogenizer mixer; (B) conveying the composition through the extruder; (C) maintaining the composition at a temperature of from about 60.degree. C. to about 160.degree. C. as it is conveyed through the extruder; (D) reducing the pressure in at least one section of the extruder downstream of the feed units sufficiently to evaporate at least a portion of the water in the composition conveyed through that section; (E) removing the evaporated water from the extruder through at least one vent in a downstream section to form a water-reduced composition; and (F) extruding the water-reduced composition through a die thereby to produce a film. In other embodiments, the invention relates to a process for producing sheets of a pressure-sensitive adhesive composition and to a process for coating a composition such as a pressure-sensitive adhesive composition onto a support web. In each of the embodiments of the invention, a film, sheet or coating composition is formed from an aqueous composition containing large amounts of water, and the product obtained is essentially water-free.