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:
Jan. 15, 1991
Filed:
Dec. 30, 1988
Applicant:
Inventors:
Lyla M El-Sayed, West Chester, PA (US);
Sanford M Marcus, Wilmington, DE (US);
Torence J Trout, Yorklyn, DE (US);
Assignee:
E. I. du Pont de Nemours and Company, Wilmington, DE (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G03G / ;
U.S. Cl.
CPC ...
430115 ; 430126 ;
Abstract
Bipolar liquid electrostatic developer consisting essentially of at least one charge director in a nonpolar liquid having dispersed therein two toner particles having opposite charge polarity which comprise at least one thermoplastic copolymer resin. The particle average by area size is less than 10 .mu.m. The ratio of the two toner particles is 5 to 95 and 95 to 5. A process of simultaneous transfer of such developer is included. The developer is useful in copying.