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:
Jan. 11, 2005
Filed:
Oct. 01, 1999
Takashi Fujimaki, Kanagawa-ken, JP;
Yoshitomo Urata, Kanagawa-ken, JP;
Takashi Fujimaki, Kanagawa-ken, JP;
Yoshitomo Urata, Kanagawa-ken, JP;
DJK Techno Science Laboratories, Inc., Kanagawa-Ken, JP;
Abstract
The invention provides a method for producing a foamed article comprising the steps of: heating a mixture comprising (a) 100 parts by weight of linear saturated polyester, (b) 0.1 to 10 parts by weight of a mixture as a coupling agent of 0 to 100% by weight of a compound having two epoxy groups in the molecule, and 100 to 0% by weight of a compound having two or more epoxy groups, and (c) 0.01 to 5 parts by weight of a metal salt of a carboxylic acid as a coupling reaction catalyst, at a temperature of a melting point of the polyester or more to provide a melt flow rate of 50 g/10 minutes or less and swell of 10 to 200%, whereby a polyester resin is formed; and heating and foaming the polyester resin using a foaming agent . A foamed article useful as cushioning material, heat insulating material, packaging material, food container, and dividers can be produced by increasing the molecular weight, melt viscosity, and swell (degree of swelling) of PET-based polyesters that have relatively low molecular weight and are brittle, especially recovered polyester, that is used as a prepolymer.