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:
Apr. 23, 1996
Filed:
May. 27, 1994
Applicant:
Inventor:
Seizo Seki, Miyagi, JP;
Assignee:
Sony Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B44C / ;
U.S. Cl.
CPC ...
426 67 ; 428 76 ; 206497 ; 206813 ; 2063871 ; 229 8705 ; 426413 ; 426414 ; 426513 ; 426412 ;
Abstract
A partly-overlapped portion of a sheath film is meltbonded by heat to provide a seal which a user can tear open with ease. A heat sealing area of the sheath film is halftone printed to reduce the bonding area, thereby decreasing the bonding strength. A tearing portion is provided along the heat seal which is printed so that it has a bonding strength which gradually increases along the tear part until it reaches the bonding strength of the remainder of the heat seal. A curl section having minimal bonding strength relative to the tearing portion of the heat seal is induced to curl up using heat treatment to allow the user to grasp the sheath film at the tear part.