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:
May. 11, 1982
Filed:
Apr. 03, 1980
Frank A Muller, Los Angeles, CA (US);
Scripto, Inc., Doraville, GA (US);
Abstract
A ballpoint writing instrument containing a supply of ink capable of producing an intense colored line when deposited on a writing paper surface that is capable of erasure within several hours after deposit by the use of a conventional pencil eraser without causing damage to the writing paper surface but which thereafter sets up to produce a permanent non-erasable line. The ink includes an elastomeric polymer such as Cis-1.4 Polyisoprene dissolved in an essentially non-volatile hydrocarbon solvent or plasticizer such as a light mineral oil and a colorant such as pigment particles evenly dispersed in the plasticized elastomeric polymer solution. The elastomeric polymer prevents the pigment colorant from penetrating into the writing paper surface. The preferred ink formulations also avoid or limit the use of volatile solvents which are detrimental to smooth writing characteristics for a ballpoint pen.