Thermal ink jet ink composition

1. A thermal ink jet ink composition comprising:

a volatile organic solvent;

a binder resin, wherein the binder resin is present in an amount from 0.3% to 8% by weight of the ink composition;

a dye;

a humectant in an amount from 1% to 40% by weight of the thermal ink jet ink composition, and

an additive for extending the decap time of the thermal ink jet ink composition, wherein the additive is present in an amount greater than 0.5% by weight of the thermal ink jet ink composition, wherein the additive is selected from the group consisting of aliphatic hydrocarbons, drying oils and mixtures thereof, wherein the additive does not phase separate from the ink jet composition during application of the ink to a substrate in thermal ink jet printing, wherein the ink composition has a decap time of greater than 30 seconds in a thermal ink jet printer, and wherein if water is present, it is present in amount up to 10% by weight of the ink composition.

2. The thermal ink jet ink composition of claim 1 , wherein the ink composition has a decap time of greater than 2 minutes in a thermal ink jet printer.

3. The thermal ink jet ink composition of claim 1 , wherein the ink composition has a dry time of less than 5 seconds in a thermal ink jet printer.

4. The thermal ink jet ink composition of claim 1 , wherein the additive comprises an aliphatic hydrocarbon selected from the group consisting of cyclic hydrocarbons, straight chain hydrocarbons, and mixtures thereof.

5. The thermal ink jet ink composition of claim 1 , wherein the additive comprises a drying oil selected from the group consisting of tung oil, linseed oil, walnut oil, poppy seed oil, perilla oil, and mixtures thereof.

6. A thermal ink jet cartridge including the thermal ink jet ink composition of claim 1 .

7. The thermal ink jet ink composition of claim 1 , wherein the one or more volatile organic solvents are selected from the group consisting of methanol, ethanol, 1-propanol, isopropanol, acetone, methyl ethyl ketone, methyl propyl ketone, methyl i-propyl ketone, 3-pentanone, cyclohexanone, methyl acetate, ethyl acetate and mixtures thereof.

8. The thermal ink jet ink composition of claim 1 , wherein the binder resin is selected from the group consisting of polyamide resins, rosin ester resins, acrylic resins, polyketone resins, cellulose nitrate resins, polyvinyl butyral resins, vinyl resins and mixtures thereof.

9. The thermal ink jet ink composition of claim 1 , wherein the dye is selected from the group consisting of acid dyes, basic dyes, solvent dyes, direct dyes, disperse dyes, mordant dyes, reactive dyes, and mixtures thereof.

10. The thermal ink jet ink composition of claim 9 , wherein the dye is selected from the group consisting of C.I. Solvent Black 29, C.I. Solvent Black 26, C.I. Solvent Black 27, C.I. Solvent Black 48, C.I. Solvent Black 3, C.I. Basic Violet 3, C.I. Solvent Red 49, C.I. Solvent Orange 54, and mixtures thereof.

11. The thermal ink jet ink composition of claim 1 , wherein the additive comprises a petroleum distillate having a boiling point of about 200° C. to about 400° C.

12. The thermal ink jet ink composition of claim 1 , wherein the volatile organic solvents is selected from methanol, ethanol, methyl ethyl ketone, or a mixture thereof.

13. The thermal ink jet ink composition of claim 1 , which further includes a humectant selected from the group consisting of polyol, glycol ether, diacetone alcohol, 2-pyrrolidinone, N-methylpyrrolidone, ethyl lactate, 1,3-dimethyl-2-imidazolidindione, propylene carbonate, alkyl esters, and mixtures thereof.

14. A thermal ink jet ink composition comprising:

a volatile organic solvent;

a binder resin, wherein the binder resin is present in an amount from 0.3% to 8% by weight of the ink composition;

a dye;

a humectant in an amount from 1% to 40% by weight of the thermal ink jet ink composition, and

an additive for extending the decap time of the thermal ink jet ink composition, wherein the additive is present in an amount greater than 0.5% by weight of the thermal ink jet ink composition, wherein the additive is selected from the group consisting of aliphatic hydrocarbons, drying oils, and mixtures thereof, wherein the ink composition has a decap time of greater than 2 minutes in a thermal ink jet printer, and wherein if water is present, it is present in amount up to 10% by weight of the ink composition.

15. The thermal ink jet ink composition of claim 14 , wherein the ink composition has a decap time of greater than 5 minutes in a thermal ink jet printer.

16. The thermal ink jet ink composition of claim 14 , wherein the ink composition has a dry time of less than 5 seconds in a thermal ink jet printer.

17. A method for printing images on a substrate with a thermal ink jet printer comprising:

directing a stream of droplets of a thermal ink jet ink composition to a substrate, wherein the ink composition comprises:

a volatile organic solvent;

a binder resin, wherein the binder resin is present in an amount from 0.3% to 8% by weight of the ink composition;

a dye;

a humectant in an amount less from 1% to by weight of the thermal ink jet ink composition, and

an additive for extending the decap time of the thermal ink jet ink composition, wherein the additive is present in an amount greater than 0.5% by weight of the thermal ink jet ink composition, wherein the additive is selected from the group consisting of aliphatic hydrocarbons, drying oils, and mixtures thereof, and wherein if water is present, it is present in amount up to 10% by weight of the ink composition; and

allowing the ink droplets to dry, thereby printing an image on the substrate,

wherein the decap time of the ink is greater than 2 minutes.

18. The method of claim 17 , wherein the ink composition has a decap time of greater than 5 minutes.

19. The thermal ink jet ink composition of claim 17 , wherein the ink composition has a dry time of less than 5 seconds in a thermal ink jet printer.