Electrophotographic liquid developer comprising acrylic or methacrylic acid ester of hydrogenated abietyl alcohol polymer
AssigneeAgfa-Gevaert
InventorsJan J. Priem, Noel J. De Volder, Yvan K. Gilliams, Walter F. De Winter
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Abstract
An electrostatic liquid developer for the development of electrostatic charge patterns comprises an electrically insulating carrier liquid having a dielectric constant of less than 3 and a volume resistivity in excess of 10.sup.9 Ohm.cm. In this electrically insulating carrier liquid are dispersed resin-precoated toner particles formed of a pigment or coloring agent precoated with a polymer of an acrylic or methacrylic acid ester of hydrogenated abietyl alcohol.
Claims11
An electrostatic liquid developer for the development of electrostatic charge patterns of the type comprising an electrically insulating carrier liquid having a dielectric constant of less than 3 and a volume resistivity in excess of 10.sup.9 Ohm.cm, and suspended within said electrically insulating carrier liquid resin-precoated toner particles, said particles comprising coloring matter dispersed within and precoated by a said polymer, wherein said precoating polymer is a polymer of a monomeric acrylic or methacrylic acid ester of hydrogenated abietyl alcohol and is obtained by in situ polymerization accompanied by mechanical mixing in the presence of said coloring matter and a polymerization initiator, said precoating polymer being generally insoluble in said carrier liquid.
A method of liquid development of an electrostatic charge pattern which comprises the steps of bringing the charge pattern in contact with a liquid developing composition comprising an electrically insulating carrier liquid having a dielectric constant of less than 3 and a volume resistivity in excess of 10.sup.9 Ohm. cm and resin-precoated toner particles suspended in said carrier liquid, said toner particles comprising colouring mattern dispersed in and precoated by a solid polymer, wherein said precoating polymer is a polymer of an acrylic or methacrylic acid ester of hydrogenated abietyl alcohol and is obtained by in situ polymerization accompanied by mechanical mixing in the presence of said coloring matter and a polymerization initiator, said precoating polymer being generally insoluble in said carrier liquid.
Dependencies are inferred from the claim text.