PIGMENT LAYER AND METHOD ESPECIALLY FOR A DURABLE INSCRIPTION OF GLASS USING A HIGH ENERGY RADIATION
A pigment layer intended more 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, and comprising at least one titanium compound and free carbon.
1 . A pigment layer for the permanent marking of glass, based on a polymer matrix which reacts predominantly with pulverization to laser irradiation, and comprising at least one titanium compound and free carbon.
2 . The pigment layer as claimed in claim 1 , wherein the titanium compound is titanium dioxide.
3 . The pigment layer as claimed in claim 1 , wherein the free carbon is formed by carbon black and/or originates from the polymer matrix decomposed, evaporated, oxidized, depolymerized and/or pyrolyzed on laser exposure.
4 . The pigment layer as claimed in claim 1 , wherein the polymer matrix is a radiation-cured polymer matrix.
5 . The pigment layer as claimed in claim 1 , having the following composition:
100 phr radiation-cured aliphatic, difunctional polyurethane acrylate, 0.2 to 2.5 phr carbon black, and 45 to 65 phr titanium dioxide.
6 . The pigment layer as claimed in claim 1 , having a thickness in a range from 20 to 500 μm.
7 . The pigment layer as claimed in claim 1 , which has had pulverized material having a number-average particle size of 0.5 to 2.0 μm is removed from the pigment layer by laser-generated burning.
8 . The pigment layer as claimed in claim 1 , being coated partially or over its whole area with an adhesive.
9 . The pigment layer as claimed in claim 1 , applied on a carrier.
10 . The pigment layer as claimed in claim 1 , deactivated by a partially applied passivating layer, on the side which is to be brought into contact with a substrate during a marking operation.
11 . A method for marking glass, which comprises applying the pigment layer of claim 1 to said glass and irradiating said pigment layer with a laser.
12 . The method of claim 11 , wherein an interference hologram is formed on said glass by said method.
13 . The method of claim 11 , wherein the pigment layer is brought by pressing into direct contact with the glass to be marked, the pigment layer is irradiated with a laser, the laser beam interacting with the pigment layer through the glass, and the marking is developed on the side of the glass remote from the laser source.
14 . The method as claimed in claim 13 , wherein the pulse duration of the laser lies between 40 and 90 ns.
15 . A glass article having markings formed with the pigment layer claim 1 .
16 . The pigment layer as claimed in claim 2 , wherein the free carbon is formed by carbon black and/or originates from the polymer matrix decomposed, evaporated, oxidized, depolymerized and/or pyrolyzed on laser exposure.
17 . The pigment layer as claimed in claim 8 , wherein said adhesive is a pressure-sensitive adhesive.
18 . The pigment layer of claim 9 , wherein said carrier is a carrier sheet.