Hp Indigo B.v.

Hewlett-packard Indigo B.v.

Hewlett-packard Development Company, L.P.

Olga Kagan

Yaron Grinwald

Rada Nuchimov

Shiran Zabar

Albert Teishev

Emad Masoud

Vladislav Kaploun

Eyal Negreanu

Danny Feldman

Guy Nesher

Haim Yosef Cohen

Reut Avigdor

Marc Klein

Gleb Romantcov

Samer Farran

Michael Kokotov

Yana Reznick

Adi Vinegrad

Adi Mann

Eyal Handel

Neta Filip-Granit

Yelena Litichevski

Ofir Bros

Ruslan Tovberg

A method for producing a conductive liquid electrophotographic ink composition is described, the method comprising: heating a polymer resin in a carrier fluid to dissolve the polymer resin; adding conductive metallic pigment particles to be coated to the carrier fluid; cooling the carrier fluid to effect precipitation of the polymer resin from the carrier fluid such that a coating of the resin is at least partially formed on the conductive metallic pigment particles; reheating the suspension of partially coated conductive metallic pigment particles in the carrier fluid; and cooling the carrier fluid at a controlled rate to effect precipitation of the polymer resin from the carrier fluid such that a coating of the resin is formed on the conductive metallic pigment particles, thereby producing the conductive liquid electrophotographic ink composition.

Metallic pigment particles

According to an example, a resin, a carrier liquid, and a pearlescent pigment may be mixed to form a liquid electrophotographic ink.

Electrophotographic ink including pearlescent pigment

Disclosed herein is an electrostatic ink composition. The composition may comprise a carrier liquid, which has suspended therein: thermochromic pigment particles having a layer of thermoplastic resin thereon. Method for forming electrostatic ink composition and a substrate having the electrostatic ink composition printed thereon are also disclosed herein.

Electrostatic ink compositions

Provided in one example herein is a liquid electrophotographic ink composition. The composition comprises: a carrier fluid comprising a polymer; ink particles each comprising a non-aqueous polymeric resin and pigment particles distributed in the polymeric resin; and a charge director. The pigment particles comprise a metal oxide and have a hydrophobic surface. The hydrophobic surface comprises at least one of the following: (i) nanoparticles attached to each of the pigment particles, the nanoparticles comprising at least one of an oxide, a phosphate, and a nitrate; (ii) a coating disposed over each of the pigment particles, the coating comprising at least one of an oxide, a phosphate, and a nitrate; and (iii) a coating disposed over each of the pigment particles, the coating comprising at least one of a polymer and an oligomer.

Ink composition with pigment particles having a hydrophobic surface

A method for coating pigment particles is provided, the method comprising heating a polymer resin in a carrier fluid to dissolve the polymer resin, suspending in the carrier fluid the pigment particles to be coated; and effecting precipitation of the polymer resin from the carrier fluid, such that a coating of the resin is formed on the pigment particles.

Liquid electrophotographic ink composition

The application relates to a method of producing an electrostatic ink composition, the method comprising: mixing a resin and a conductive pigment in a continuous mixer to form a compounded mixture comprising particles comprising the resin and the pigment; adding a liquid carrier to the compounded mixture, such that the particles comprising the resin and the conductive pigment are dispersed in the liquid carrier; and, before, during or after adding the liquid carrier to the compounded mixture: imparting a charge on the particles comprising the resin and the pigment.

Electrostatic inks and method for their production

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Nes Ziona, Israel

Olga Kagan