Michele J Shepard

US Patent:

51804255, Jan 19, 1993

Filed:

Nov 5, 1991

Appl. No.:

7/788141

Inventors:

Howard Matrick - Highlands NJ
Michele E. Shepard - Escondido CA
Young S. You - Los Altos CA

Assignee:

E. I. Du Pont de Nemours and Company - Wilmington DE

International Classification:

C09D 1100
C08K 500

US Classification:

106 22R

Abstract:

An ink for ink jet printers which comprises an aqueous carrier medium, pigment dispersion or dye and a polyol/alkylene oxide condensate cosolvent which eliminates film formation on thermal ink jet resistor surfaces thereby eliminating non-uniformity in optical density. The cosolvent present at least 5% has a solubility in water of at least 4. 5 parts in 100 parts of water at 25. degree. C. and a general formula: ##STR1## wherein X=--H or --CH. sub. 3 ; R=--H, --CH. sub. 3, --C. sub. 2 H. sub. 5, --C. sub. 3 H. sub. 7, --C. sub. 4 H. sub. 9, or --CH. sub. 2 O(CH. sub. 2 CH. sub. 2 O). sub. e H; b=0 or 1, a+d+f(c+e)=2-100; and f=1-6, the cosolvent being present in the amount of at least 4. 5% based on the total weight of the ink jet ink composition. These inks exhibit freedom from thermal resistor film formation, have excellent decap performance, are storage stable and give images having excellent print quality.

US Patent:

52213340, Jun 22, 1993

Filed:

Jun 13, 1991

Appl. No.:

7/714878

Inventors:

Howard Matrick - Highlands NJ
Arthur C. Shor - Concordville PA
Harry J. Spinelli - Wilmington DE
Michele E. Shepard - Escondido CA
Jerome Hochberg - Wilmington DE

Assignee:

E. I. Du Pont de Nemours and Company - Wilmington DE

International Classification:

C09D 1100
C09D 1110

US Classification:

106 20D

Abstract:

A pigmented ink for ink jet printers which comprises an aqueous carrier medium, pigment particles dispersed in an AB or BAB block copolymer having a hydrophilic segment and a segment that links to the pigment, and an effective amount of a surfactant sufficient to decrease the drying time of the ink. The A block and the B block(s) have molecular weights of at least 300. These inks give images having good print quality, water and smear resistance, lightfastness, and storage stability.