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. 03, 1984
Filed:
Jun. 21, 1982
Edward Hatchadoorian, Wilmington, DE (US);
George J Ostapchenko, Wilmington, DE (US);
James L Patton, Wilmington, DE (US);
Harlan S Young, Wilmington, DE (US);
E. I. DuPont de Nemours and Company, Wilmington, DE (US);
Abstract
Reinforced poly(ethylene terephthalate) sheets are thermoformed to articles having one or more surfaces in contact with the mold of such a degree of smoothness that they virtually completely replicate the mold face. When the mold face is completely smooth, the concave imperfections caused by air entrapment in the plastic material account for less than 6% of the surface area. Composite articles consisting of a face member and a backing member are made by thermoforming in a single mold a face member having one or more surfaces in contact with the mold face of such a degree of smoothness that it completely replicates the mold face, and its proportion of concave imperfections is less than about 6% of the surface area. The backing member is bonded in the mold with an adhesive to the face member, and the composite structure is allowed to remain in the mold for a sufficient time to permit subsequent removal without distortion. The initial polymer sheets are less than about 5% crystalline, but the thermoformed article is left in the mold until it crystallizes to the desired degree.