Eastman-Kodak Company

Khe C Nguyen

William T Gruenbaum

Thomas R Klose

Jeanne Ellen Kaeding

An electrophotographic coating composition comprising finely-divided photoconductive perylene pigment dispersed in a solvent solution of polymeric binder is prepared by the steps of (1) milling a perylene pigment with milling media comprising inorganic salt and non-conducting particles under shear conditions in the substantial absence of the solvent to provide pigment having a particle size up to 0.2 micrometer, (2) continuing the milling at higher shear at a temperature up to about 50.degree. C., to achieve a perceptible color change of the pigment particles, (3) rapidly reducing the temperature of the milled pigment by at least 10.degree. C., (4) separating the milled pigment from the media and (5) mixing the milled pigment with the solvent solution of polymeric binder to form the coating composition. A very high degree of dispersion of photoconductive perylene pigment in solvent solution of polymeric binder is achieved by this method.

Method for preparing coating compositions containing photoconductive

An electrophographic recording element comprising a combination of photoconductive titanyl phthalocyanine and titanyl fluorophthalocyanine pigments. The pigments or charge-generation materials are dispersed in a binder to form a layer having excellent photosensitivity and resistance to abrasion.

Electrophotographic recording elements containing a combination of

An electrophotographic recording element having a layer formed from a liquid composition comprising polymeric binder and dispersed photoconductive titanyl phthalocyanine particles. The titanyl phthalocyanine particles have a particle size up to about 0.2 micrometer and are characterized by certain X-ray diffraction characteristics and the layers are characterized by certain spectral absorption ranges. The coating composition comprises finely-divided photoconductive titanyl phthalocyanine particles dispersed in a solvent solution of polymeric binder and is prepared by the steps of (1) milling a titanyl phthalocyanine pigment with milling media comprising inorganic salt and non-conducting particles under shear conditions in the substantial absence of the solvent to provide pigment having a particle size up to 0.2 micrometer, (2) continuing the milling at higher shear at a temperature up to about 50.degree. C. to achieve a perceptible color change of the pigment particles, (3) rapidly increasing the temperature of the milled pigment by at least 10.degree. C., (4) separating the milled pigment from the milling media and (5) mixing the milled pigment with the solvent solution of polymeric binder to form the coating composition.

Electrophotographic recording elements containing titanyl phthalocyanine

An electrophotographic recording element having a layer comprising a photoconductive perylene pigment, as a charge generation material, that is sufficiently finely and uniformly dispersed in a polymeric binder to provide the element with excellent electrophotographic speed. The perylene pigments are perylene-3,4,9,10-tetracarboxylic acid imide derivatives.

Electrophotographic recording elements containing photoconductive

An electrophotographic recording element comprising a combination of photoconductive perylene materials that are dispersed in a binder to form layers having excellent photosensitivity and resistance to abrasion. The materials are perylene-3,4,9,10-tetracarboxylic acid imide derivatives that contain a phenethyl radical bonded to a 3,4-dicarboximide nitrogen atom.

Growing community of inventors

Pittsford, NY, United States of America

Khe C Nguyen