Pigment layer and method of permanently scribing a substrate by means of high-energy radiation
View Patent ↗Pigment layer intended particularly for the permanent marking of glass, based on a polymer matrix which reacts predominantly with pulverization to a high-energy beam, more particularly to laser irradiation, comprising at least one titanium donor and a carbon donor which provides free carbon under energy irradiation.
1. Pigment layer intended for the permanent marking of a substrate, based on a polymer matrix which reacts predominantly with pulverization to high-energy radiation, wherein the pigment layer has the following composition:
100 phr
polymer matrix,
0.2 phr to 2.5 phr
carbon black and
45 phr to 65 phr
titanium dioxide.
2. Pigment layer according to claim 1 , which is formed free from plastics which melt under energy irradiation and/or free from a glass frit.
3. Pigment layer according to claim 1 , wherein the polymer matrix functions as a carbon donor, free carbon originating from the polymer matrix decomposed, evaporated, oxidized, depolymerized and/or pyrolysed under exposure to radiation.
4. Pigment layer according claim 1 , wherein the polymer matrix is a radiation-cured polymer matrix.
5. Pigment layer according to claim 1 , wherein the polymer matrix is a thermoset polymer matrix.
6. Pigment layer according claim 1 , which has a thickness of the pigment layer in a range from about 20 μm to about 500 μm.
7. Pigment layer according to claim 1 , wherein the pulverized material removed from the pigment layer by means of energy irradiation has a number-average particle size of about 0.5 μm to about 2.0 μm.
8. Pigment layer according to claim 1 , which is coated partially or over its whole area with an adhesive.
9. Pigment layer according to claim 1 , which is applied on a carrier.
10. Pigment layer according to claim 1 , which is deactivated as a result of a partially applied passivating layer, the passivation being on the side of the pigment layer that, during the marking operation, is in contact with the substrate.
11. A method of marking glass comprising applying a pigment layer according to claim 1 to the glass.
12. Method according to claim 11 , wherein the applied marking is a computer-generated hologram or an interference hologram.
13. Method of marking a substrate, said method comprising bringing a pigment layer by pressing into direct contact with the substrate to be scribed, the pigment layer being formed according to claim 1 ,
and irradiating the pigment layer with high-energy radiation, as a result of which the polymer matrix is pulverized and free carbon is formed, and
wherein, as a result of the irradiation, a marking is formed on the substrate.
14. Method according to claim 13 , wherein the marking is carried out with exclusion of a glass frit and/or with exclusion of a plastic which melts under energy irradiation.
15. Method according to claim 13 , wherein a transparent substrate is marked, the irradiation taking place through the substrate and the marking being formed on the side of the substrate that is remote from the radiation source.
16. Method according to claim 13 , wherein the irradiation is carried out by means of a laser as radiation source.
17. Method according to claim 13 , wherein the irradiation is carried out with a pulse duration of less than 90 ns.
18. Glass article marked using a pigment layer according to claim 1 .
19. Glass article according to claim 18 , which has titanium carbide on its surface.