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:
Nov. 13, 2001
Filed:
Oct. 20, 1997
Applicant:
Inventor:
Gerhard Lugert, Nürnberg, DE;
Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C08D 1/300 ;
U.S. Cl.
CPC ...
C08D 1/300 ;
Abstract
A simplified method for producing a lead for color pencils, cosmetic pencils and colored chalk with good down stroke behavior involves mixing powdered or granular base materials containing a thermolabile, polymeric binding agent, inorganic filler materials and a coloring agent with water and then extruding the mixed materials to form raw leads, which extruded material is subsequently heat treated at the binding agent decomposition temperature for a time sufficient to partially decompose the binding agent. Enough water is mixed with the base material to achieve a lead mass of approximately 5 parts by weight of base material and 1 part by weight of water.