Use of transition metal compounds in imageable coatings
A process for forming an image on a substrate, which comprises coating the substrate with an amine of molybdenum, tungsten or vanadium that changes colour on heating or irradiation as an aqueous dispersion or suspension or as a solution in an organic solvent. Also described is a coated substrate, wherein the coating is a substantially visible light-transparent layer comprising an amine compound of molybdenum, tungsten or vanadium, and a solution of said amine compound and a thermoplastic polymer or a photo-polymerisable monomer.
1. A method for forming an image on a substrate, which comprises coating the substrate with a substantially visible light-transparent solution, in an organic solvent, of an amine compound of molybdenum, tungsten or vanadium that changes colour on heating or irradiation, and heating or irradiating the coating, wherein the amino is a secondary or tertiary alkylamine in which each alkyl group has up to 12 carbon atoms and the amine has up to 24 carbon atom, wherein the amine is of molybdenum (VI).
2. A method for forming an image on a substrate, which comprises coating the substrate with a substantially visible light-transparent aqueous dispersion or suspension, of an amine compound of molybdenum, tungsten or vanadium that changes colour on heating or irradiation, and heating or irradiating the coating, wherein the amine is a secondary or tertiary alkylamine in which each alkyl group has up to 12 carbon atoms, and the amine has up to 24 carbon atoms wherein the amine compound is of molybdenum (VI).
3. The method according to claim 1 , wherein the coating also comprises the use of an organic polymer binder.
4. Time method according to claim 1 , wherein the coating also comprises the use of a colour-former.
5. The method according to claim 1 wherein the substrate is substantially transparent to visible light.
6. The method according to claim 1 , wherein the coating additionally comprising IR absorber that absorbs laser radiation.
7. A coated substrate, wherein the coating is a substantially visible light-transparent layer comprising an amine compound of molybdenum, tungsten or vanadium that changes colour on heating or irradiation, wherein the amine is a secondary or tertiary alkylamine in which each alkyl group has up to 12 carbon atoms and the amine has up to 24 carbon atoms, and wherein the substrate is also substantially transparent to visible light, wherein the amine compound is of molybdenum (VI).
8. The coated substrate according to claim 7 , wherein the coating also comprises arm organic polymer binder.
9. The coated substrate according to claim 7 , wherein the substrate is also substantially transparent to visible light.
10. The coated substrate according to claim 7 , including also an image formed therein by heating or irradiation.
11. The coated substrate according to claim 7 , wherein the coating additionally comprises aim IR absorber that absorbs laser radiation.
12. A solution of an amine compound of molybdenum, tungsten or vanadium that changes colour on heating or irradiation and one of the following:
a thermoplastic polymer;
or a photopolymerisable monomer,
and wherein the amine is a secondary or tertiary alkylamine in which each alkyl group has up to 12 carbon atoms and the amine has up to 24 carbon atoms, wherein the amine compound is of molybdenum (VI).
13. The solution according to claim 12 , which is fluid at or below 150° C.
14. The method according to claim 2 , wherein the coating also comprises the use of an organic polymer binder.
15. The method according to claim 2 , wherein the coating also comprises the use of a colour-former.
16. The method according to claim 2 , wherein the substrate is substantially transparent to visible light.
17. The method according to claim 2 , wherein the coating additionally comprises an IR absorber that absorbs laser radiation.
18. The coated substrate according to claim 7 , wherein the coating also comprises the use of a colour-former.
19. A method for forming an image on a substrate, which comprises coating the substrate with a substantially visible light-transparent solution, in an organic solvent, of an amine compound of molybdenum, tungsten or vanadium that changes colour on heating or irradiation, and heating or irradiating the coating, wherein the amine is a secondary or tertiary alkylamine in which each alkyl group has up to 12 carbon atoms and the amine has up to 24 carbon atoms, wherein the coating is irradiated using a laser, and wherein the laser light has a wavelength of 800-1500 nm.
20. The method according to claim 19 , wherein the coating also comprises the use of an organic polymer binder.
21. The method according to claim 19 , wherein the coating also comprises the use of a colour-former.
22. The method according to claim 19 , wherein the substrate is substantially transparent to visible light.
23. The method according to claim 19 , wherein the coating additionally comprises an IR absorber that absorbs laser radiation.
24. A method for forming an image on a substrate, which comprises coating the substrate with a substantially visible light-transparent aqueous dispersion or suspension, of an amine compound of molybdenum, tungsten or vanadium that changes colour on heating or irradiation, and heating or irradiating the coating, wherein the amine is a secondary or tertiary alkylamine in which each alkyl group has up to 12 carbon atoms and the amine has up to 24 carbon atoms, wherein the coating is irradiated using a laser, and wherein the laser light has a wavelength of 800-1500 nm.
25. The method according to claim 24 , wherein the coating also comprises the use of an organic polymer binder.
26. The method according to claim 24 , wherein the coating also comprises the use of a colour-former.
27. The method according to claim 24 , wherein the substrate is substantially transparent to visible light.
28. The method according to claim 24 , wherein the coating additionally comprises an IR absorber, that absorbs laser radiation.