Ink jet ink composition
AssigneeLexmark International, Inc.
InventorsSusan Hardin Butler, Jing X. Sun
Life of this patent
Estimating the term…
Abstract
The invention provides an ink composition having improved printing performance. The ink composition includes an ink vehicle, from about 0.1 to about 10% by weight self-dispersed ink pigment, from about 0.1 to about 10% by weight dye, a humectant, and a penetrant, wherein the weight ratio of ink pigment to dye ranges from greater than about 0.75:1 to less than about 2.5:1. Such ink compositions exhibit substantially improved permanence, decreased drying time, and high optical density compared to ink compositions containing only ink pigment or dye.
Claims20
An ink jet ink composition comprising an ink vehicle, from about 0.1 to about 10% by weight self-dispersed ink pigment;
- from about 0.1 to about 10% by weight dye;
- a humectant selected from the group consisting of dipropylene glycol, tripropylene glycol, triethylene glycol, tetraethylene glycol, 1,(2,-hydroxyethyl)-2-pyrrolidone, trimethyolpropane, 1,2-propanediol, 1,3-propanediol, 1,5-pentanediol, 2-pyrrolidone, polyethylene glycol, diethylene glycol, 2,2-thiodiethanol, and mixtures thereof;
- and a penetrant selected from the group consisting of 1,2-hexandiol, hexyl carbitol, diethylene glycol butyl ether, diethylene glycol benzyl ether, n-propyl alcohol, secondary alcohol ethoxylates, ethoxylated acetylenic diols, polyalkyleneoxide-modified heptamethyl-trisiloxane, and mixtures thereof, wherein the weight ratio of ink pigment to dye ranges from greater than about 0.75:1 to less than about 2.5:1, and wherein the self-dispersed ink pigment comprises an oxidized carbon black having a surface containing a steric inducing group thereon obtained by reacting the carbon black with thionyl halide and a steric inducing compound selected from the group consisting of a monoalkoxy-terminated polyalkylene glycol, a mono-amine terminated polyalkylene glycol compound, 2-hydroxyethylpyrrolidinone, 2-hydroethylmorpholine, and 2-hydroxyethyloxazolidone.
A method for improving the printing characteristics of an ink jet ink composition comprising preparing an ink formulation containing from about 0.1 to about 10% by weight self-dispersed ink pigment, from about 0.1 to about 10% by weight dye, and water and mixing a humectant, a penetrant, and optionally a biocide with the ink formulation to provide an ink composition, wherein the weight ratio of ink pigment to dye in the ink composition ranges from greater than about 0.75:1 to less than about 2.5:1, and wherein the self-dispersed ink pigment comprises self-dispersed carbon black having a surface modified by reacting the self-dispersed carbon black with thionyl halide and then with a steric inducing compound selected from the group consisting of a monoalkoxy-terminated polyalkylene glycol compound, a mono-amine terminated compound, 2-hydroxyethylpyrrolidinone, 2-hydroethylmorpholine, and 2-hydroxyethyloxazolidone to provide a steric inducing group on the carbon black.
An ink jet printer containing an ink jet ink composition comprising an ink vehicle, from about 0.1 to about 10% by weight self-dispersed ink pigment;
- from about 0.1 to about 10% by weight dye;
- a humectant selected from the group consisting of dipropylene glycol, tripropylene glycol, triethylene glycol, tetraethylene glycol, 1,(2,-hydroxyethyl)-2-pyrrolidone, trimethyolpropane, 1,2-propanediol, 1,3-propanediol, 1,5-pentanediol, 2-pyrrolidone, polyethylene glycol, diethylene glycol, 2,2-thiodiethanol, and mixtures thereof;
- and a penetrant selected from the group consisting of 1,2-hexandiol, hexyl carbitol, diethylene glycol butyl ether, diethylene glycol benzyl ether, n-propyl alcohol, secondary alcohol ethoxylates, ethoxylated acetylenic diols, polyalkyleneoxide-modified heptamethyl-trisiloxane, and mixtures thereof, wherein the weight ratio of ink pigment to dye ranges from greater than about 0.75:1 to less than about 2.5:1, and wherein the self-dispersed ink pigment comprises an oxidized carbon black having a surface containing a steric inducing group thereon obtained by reacting the carbon black with thionyl halide and a steric inducing compound selected from the group consisting of a monoalkoxy-terminated polyalkylene glycol, a mono-amine terminated polyalkylene glycol compound, 2-hydroxyethylpyrrolidinone, 2-hydroethylmorpholine, and 2-hydroxyethyloxazolidone.
Dependencies are inferred from the claim text.