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.

Date of Patent:
Dec. 15, 1981

Filed:

Dec. 28, 1979
Applicant:
Inventor:

Edwin C McLaren, Apple Valley, MN (US);

Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B31F / ; B32B / ;
U.S. Cl.
CPC ...
156227 ; 53458 ; 156 69 ; 1563096 ; 229-45 ; 229-55 ; 229 24 ; 229 / ; 428 35 ; 428121 ; 493133 ; 493140 ; 493152 ;
Abstract

A multi-piece, tub shaped paperboard container having a circular opening in the top thereof is provided with a multi-piece, reinforced rim coated with a layer of meltable plastic and is assembled by applying heat to overlapping seams in order to melt the plastic coating and thereby seal the seams. Heat is applied evenly around the entire periphery of the rim by a 2-piece, annularly shaped, heated collar which may be selectively shifted into conforming engagement with the container. The even application of heat around the entire periphery of the rim equalizes the surface tension of the plastic coating during melting thereof to avoid deformation of the rim during the heat sealing process.


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