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:
Jul. 27, 1976
Filed:
Aug. 17, 1973
Masahide Yazawa, Tokyo, JA;
Polymer Processing Research Institute Ltd., Tokyo, JA;
Abstract
Flat plate-type, rod-type or shaped articles of polystyrene foam are continuously produced from preliminarily expanded beads of polystyrene or a mixture of said preliminarily expanded beads with foamed polystyrene pieces recovered for reuse as raw materials by enveloping the beads with a circulating steam-permeable belt, such as cloth belt, passing the enveloped beads through a pressure sealing conduit capable of throttling and succesively a heating zone in a pressure steam chamber at a temperature between 100.degree. and 125.degree.C, thereby softening and re-expanding the preliminarily expanded beads by steam heating, reducing the apparent volume of the enveloped re-expanded beads in a course towards a pressure sealing conduit at an outlet of the pressure steam chamber, thereby allowing the softened and re-expanded beads to adhere tightly one to another in a continuous foamed mass, or also additionally to a liner material, when accompanied therewith, cooling the enveloped foamed mass while maintaining a limited volume of the enveloped foamed mass, and separating the resulting shaped product of foamed mass from the belt by a set of rollers at the end of processing line.