Ink jet ink containing at least one pigment and at least one oxidized carbon black. The ink jet ink is prepared in a process wherein the pigment is dispersed in at least one solvent, followed by addition of the oxidized carbon black and renewed dispersing. The ink jet ink can be used for printing textiles, metal, foil, film, sheet, glass and paper.
1. An ink jet ink, comprising at least one pigment and at least one oxidized carbon black, wherein said oxidized carbon black:
a) is obtained by a process consisting of treating a carbon black with one or more oxidizing agents; and
b) has a pH in the range of from 1 to 5 as measured according to ISO787-9;
c) has a volatiles content in the range of from 10% to 30%.
2. The ink jet ink of claim 1 , wherein said oxidized carbon black has a volatiles content in the range of from 15% to 25%.
3. The ink jet ink of claim 1 , wherein said one or more oxidizing agents are selected from the group consisting of: ammonium peroxodisulphate, hydrogen peroxide, ozone, oxygen (pure or as air), potassium bromate and sodium perborate.
4. The ink jet ink of claim 2 , wherein the weight ratio of pigment to oxidized carbon black is in the range of from 0.5 to 0.1.
5. The ink jet ink of claim 1 , wherein the oxidized carbon black content in said ink jet ink is in the range of from of 0.5% to 5.6% by weight.
6. The ink jet ink of claim 5 , wherein said oxidized carbon black has a volatiles content in the range of from 15% to 25%.
7. The ink jet ink of claim 6 , wherein the weight ratio of pigment to oxidized carbon black is in the range of from 0.5 to 0.1.
8. The ink jet ink of claim 5 , wherein the weight ratio of pigment to oxidized carbon black is in the range of from 0.5 to 0.1.
9. The ink jet ink of claim 1 , wherein the pigment content is in the range from 0.05% to 2.8% by weight.
10. The ink jet ink of claim 9 , wherein said oxidized carbon black has a volatiles content in the range of from 15% to 25% and the weight ratio of pigment to oxidized carbon black is in the range of from 0.5 to 0.1.
11. The ink jet ink of claim 9 , wherein the oxidized carbon black content in said ink jet ink is in the range of from of 0.5% to 5.6% by weight; and said oxidized carbon black has a volatiles content in the range of from 15% to 25%.
12. The ink jet ink of claim 11 , wherein the weight ratio of pigment to oxidized carbon black is in the range of from 0.5 to 0.1.
13. A process for preparing the ink jet ink of claim 1 , comprising:
a) dispersing a pigment in at least one solvent;
b) adding an oxidized carbon black, wherein said oxidized carbon black:
i) is obtained by a process consisting of treating a carbon black with one or more oxidizing agents; and
ii) has a pH in the range of from 1 to 5 as measured according to ISO787-9; and
c) dispersing said pigment and said oxidized carbon black in said solvent.
14. In an ink jet printing process, the improvement comprising reducing intercolour bleeding by using an ink comprising at least one pigment and at least one oxidized carbon black, wherein said oxidized carbon black:
a) is obtained by a process consisting of treating a carbon black with one or more oxidizing agents; and
b) has a pH in the range of from 1 to 5 as measured according to ISO787-9;
c) has a volatiles content in the range of from 10% to 30%.
15. The improvement of claim 14 , wherein said oxidized carbon black in said ink has a volatiles content in the range of from 15% to 25%.
16. The improvement of claim 14 , wherein the weight ratio of pigment to oxidized carbon black in said ink is in the range of from 0.5 to 0.1.
17. The improvement of claim 15 , wherein the weight ratio of pigment to oxidized carbon black in said ink is in the range of from 0.5 to 0.1.
18. The improvement in claim 14 , wherein the oxidized carbon black content in said ink jet ink is in the range of from of 0.5% to 5.6% by weight.
19. The improvement of claim 14 , wherein said ink jet ink printing process is used for printing textiles, metal, foil, film, sheet, glass or paper.
20. The improvement of claim 14 , wherein:
a) said oxidized carbon black in said ink has a volatiles content in the range of from 15% to 25%;
b) the weight ratio of pigment to oxidized carbon black in said ink is in the range of from 0.5 to 0.1; and
c) the oxidized carbon black content in said ink jet ink is in the range of from of 0. 5% to 5.6% by weight.