Electrostatic ink compositions

Abstract

A magenta liquid electrostatic ink composition includes chargeable particles having a resin and a pigment; an insulating, non-polar, non-aqueous liquid carrier in which the chargeable particles are dispersed; and a charge director. The resin is formable from polymerizing alkylene monomers and methacrylic or acrylic acid monomers; the pigment is selected from pigment violet 19 type α I , pigment violet 19 type α II , pigment violet 19 type 1, pigment red 177, pigment red 208, and pigment violet 32; and the liquid electrostatic ink composition lacks any other types of pigment.

What is claimed is: 
     
         1 . A magenta liquid electrostatic ink composition, comprising:
 chargeable particles comprising a resin and a pigment;   an insulating, non-polar, non-aqueous liquid carrier in which the chargeable particles are dispersed; and   a charge director;   wherein:
 the resin is formable from polymerizing alkylene monomers and methacrylic or acrylic acid monomers; 
 the pigment is selected from pigment violet 19 type α I , pigment violet 19 type α II , pigment violet 19 type β, pigment red 177, pigment red 208, and pigment violet 32; and 
 the liquid electrostatic ink composition lacks any other types of pigment. 
   
     
     
         2 . The magenta liquid electrostatic ink composition according to  claim 1 , wherein the pigment is a mixture of a plurality of pigments selected from pigment violet 19 type α I , pigment violet 19 type α II , pigment violet 19 type β, pigment red 177, pigment red 208, and pigment violet 32. 
     
     
         3 . The magenta liquid electrostatic ink composition according to  claim 1 , wherein the pigment is a mixture of a first pigment selected from pigment violet 19 type α II , pigment red 177 and pigment red 208, and a second pigment selected from pigment violet 19 type α I , pigment violet 19 type β, pigment red 122, and pigment violet 32. 
     
     
         4 . The magenta liquid electrostatic ink composition according to  claim 1 , wherein the pigment is pigment violet 19 type α II , and wherein the liquid electrostatic ink composition lacks another pigment. 
     
     
         5 . The magenta liquid electrostatic ink composition according to  claim 1  wherein total solids of the magenta liquid electrostatic ink composition consist of:
 a) 1-45 wt % of a pigment, wherein the pigment is selected from pigment violet 19 type α I , pigment violet 19 type α II , pigment violet 19 type β, pigment red 177, pigment red 208, and pigment violet 32; and 
 b) 40-90 wt % of one or more resins; 
 c) 0.0001-20 wt % of one or more charge directors; and 
 d) optionally, up to 10 wt % of other additives, wherein other additives lacks any other types of pigment. 
 
     
     
         6 . The magenta liquid electrostatic ink composition according to  claim 5 , wherein the pigment is a mixture of a plurality of pigments selected from pigment violet 19 type α I , pigment violet 19 type α II , pigment violet 19 type β, pigment red 177, pigment red 208, and pigment violet 32. 
     
     
         7 . The magenta liquid electrostatic ink composition according to  claim 5 , wherein the pigment is a mixture of a first pigment selected from pigment violet 19 type α II , pigment red 177, and pigment red 208, and a second pigment selected from pigment violet 19 type α I , pigment violet 19 type β, pigment red 122, and pigment violet 32. 
     
     
         8 . The magenta liquid electrostatic ink composition according to  claim 5 , wherein the pigment is pigment violet 19 type α II , and wherein the liquid electrostatic ink composition lacks another pigment. 
     
     
         9 . The magenta liquid electrostatic ink composition according to  claim 1 , wherein the magenta liquid electrostatic ink composition further comprises a charge adjuvant in an amount of less than 5 wt % of total solids of the magenta liquid electrostatic ink composition. 
     
     
         10 . The magenta liquid electrostatic ink composition according to  claim 1 , wherein the pigment is present in an amount ranging from 1 wt % to 28.69 wt %, based on a total weight of total solids of the magenta liquid electrostatic ink composition. 
     
     
         11 . The magenta liquid electrostatic ink composition according to  claim 1 , further comprising aluminum tristearate and a palmitate salt. 
     
     
         12 . The magenta liquid electrostatic ink composition according to  claim 11 , wherein the aluminum tristearate and palmitate salt make up 2% of total solids of the magenta liquid electrostatic ink composition. 
     
     
         13 . The magenta liquid electrostatic ink composition according to  claim 1 , wherein the charge director is selected from the group consisting of polybutylene succinimides and glyceride salts. 
     
     
         14 . The magenta liquid electrostatic ink composition according to  claim 1 , wherein the insulating, non-polar, non-aqueous liquid carrier includes an aliphatic hydrocarbon, an isomerized aliphatic hydrocarbon, a branched chain aliphatic hydrocarbon, an aromatic hydrocarbon, an isoparaffinic compound, a paraffinic compound, or a dearomatized hydrocarbon compound. 
     
     
         15 . A method of electrostatic printing, the method comprising:
 a) providing a magenta liquid electrostatic ink composition according to  claim 1 ;   b) contacting the electrostatic ink composition with a latent electrostatic image on a surface to create a developed image; and   c) transferring the developed image to a print substrate.   
     
     
         16 . A print substrate having printed thereon an electrostatic ink composition comprising a resin, a charge director, and a pigment;
 wherein:
 the resin is formable from polymerizing alkylene monomers and methacrylic or acrylic acid monomers; 
 the pigment is selected from pigment violet 19 type α I , pigment violet 19 type α II , pigment violet 19 type β, pigment red 177, pigment red 208, and pigment violet 32; and 
 the electrostatic ink composition lacks any other types of pigment. 
   
     
     
         17 . A magenta liquid electrostatic ink composition, comprising:
 chargeable particles comprising a resin and a pigment;   an insulating, non-polar, non-aqueous liquid carrier in which the chargeable particles are dispersed; and   a charge director;   wherein:
 the resin is formable from polymerizing alkylene monomers and methacrylic or acrylic acid monomers; 
 the pigment is a mixture of pigment red 208 and a second pigment selected from pigment red 122, pigment violet 19 type α I , pigment violet 32, and pigment violet 19 type β; and 
 the liquid electrostatic ink composition lacks any other types of pigment.