METHOD OF EJECTING SOLVENT-BASED INK COMPOSITION COMPRISING ACETATE SOLVENT

1 . A method of ejecting ink from a thermal inkjet printhead, said method comprising the steps of:

(i) supplying an ink to at least one nozzle chamber of said printhead; and

(ii) actuating a heater element in said nozzle chamber and heating said ink to a temperature sufficient to form a bubble therein, thereby causing said ink to be ejected from a nozzle opening associated with said nozzle chamber, wherein said ink is a solvent-based ink composition comprising:

(a) 20-80 wt. % of a compound of formula (C);

wherein:

R 7 is a C 2-12 alkyl group interrupted with 0, 1, 2 or 3 oxygen atoms;

(b) 10-70 wt. % of a C 1-6 alcohol; and

(c) 0.01-25 wt. % of a colorant.

2 . The method of claim 2 , wherein said ink is ejected onto a non-porous or a semi-porous substrate.

3 . The method of claim 2 , wherein said ink adheres to said substrate.

4 . The method of claim 2 , wherein said substrate is a plastics substrate.

5 . The method of claim 2 , wherein said substrate is comprised of untreated vinyl or polyester.

6 . The method of claim 1 , wherein said heater element has a mass of less than 1 nanogram.

7 . The method of claim 1 , wherein said heater element is suspended in said ink chamber, such that said ink composition envelops said heater element.

8 . The method of claim 1 , wherein an actuation energy for said heater element is less than 500 nJ.

9 . The method of claim 1 , wherein said printhead is a stationary pagewidth printhead.

10 . The method of claim 1 , wherein said printhead comprises at least 50,000 nozzles.

11 . The method of claim 1 , wherein R 7 is a C 4-8 alkyl group interrupted with 0, 1 or 2 oxygen atoms.

12 . The method of claim 1 , wherein said compound of formula (C) is selected from the group consisting of: hexyl acetate; carbitol acetate; butyldiglycol acetate; and methoxypropyl acetate.

13 . The method of claim 1 , wherein said C 1-6 alcohol is ethanol.

14 . The method of claim 1 , further comprising:

0.001-10 wt. % of a surfactant.

15 . The method of claim 1 , wherein said ink composition does not comprise an acrylate polymer or copolymer.

16 . The method of claim 1 , wherein said ink composition does not comprise any polymers.

17 . The method of claim 1 , wherein said ink composition consists only of said compound of formula (C), said C 1-6 alcohol and said colorant.

18 . The method of claim 1 , wherein said ink composition consists only of said compound of formula (C), said C 1-6 alcohol, said colorant and 0.01-10 wt. % of a surfactant.

19 . An inkjet printer comprising:

an ink reservoir containing a respective ink; and

a thermal inkjet printhead in fluid communication with said ink reservoir, wherein said ink is a solvent-based ink composition comprising:

(a) 20-80 wt. % of a compound of formula (C);

wherein:

R 7 is a C 2-12 alkyl group interrupted with 0, 1, 2 or 3 oxygen atoms;

(b) 10-70 wt. % of a C 1-6 alcohol; and

(c) 0.01-25 wt. % of a colorant.

20 . The inkjet printer of claim 19 , wherein said thermal inkjet printhead comprises a plurality of nozzles, each of said plurality of nozzles comprising:

a nozzle chamber containing said ink, said nozzle chamber having a nozzle opening for ejection of said ink; and

a heater element in contact with said ink, said heater element being configured for heating said ink to a temperature sufficient to form a bubble therein and thereby cause ejection of said ink from said nozzle opening.