Protective film for metal mesh touch sensor
Touchscreen, comprising: a display device; a touch sensor over the display device; and, a cover lens; wherein the touch sensor comprises: a transparent substrate; a layer of catalytic photoresist patterns of a catalytic photoresist composition, the catalytic photoresist composition including a photoresist and catalytic nanoparticles; a metal conductive layer with conductive patterns over the layer of catalytic photoresist patterns; a metal passivation layer over the metal layer; and a transparent protective layer over the metal passivation layer.
1. A method of manufacturing a touch sensor with a conductive micro-mesh comprising:
applying the catalytic photoresist composition onto a transparent substrate of the touch sensor;
photo patterning the catalytic photoresist composition to have a layer of catalytic photoresist pattern;
plating a metal layer on the layer of catalytic photoresist pattern thereby forming the conductive micro-mesh;
applying a metal passivation layer over the metal layer;
degassing a clear protective coating solution;
applying the clear protective coating over the metal passivation layer; and
curing the protective coating prior to attaching a flex cable to the touch sensor.
2. The method of claim 1 , wherein applying a protective coating comprises applying a solution comprising: 70%-80% monofunctional acrylic oligomers and 20%-30% solvent.
3. The method of claim 2 , wherein the curing is performed by baking the protective coating.
4. The method of claim 3 , wherein the baking is performed at a temperature of from about 100 to about 120 degrees Celsius, for a period of from 30 to about 40 seconds.
5. The method of claim 2 , further comprising including 1-6% photoinitiators in the solution and wherein the curing is performed by irradiating the protective coating with UV radiation.
6. The method of claim 1 , wherein applying the protective coating comprises applying coating solution over the conductive micro-mesh and a bond pad area of the touch sensor.
7. The method of claim 6 , further comprising adhering the flex cable to the bond pad area.
8. The method of claim 7 , wherein adhering the flex cable comprises causing solder particle suspended in an adhesive to penetrate the protective coating.
9. The method of claim 1 , wherein applying the protective coating comprises applying a protective solution to a thickness of 1-2 microns.
10. The method of claim 1 , wherein curing the protective coating comprises applying one of thermal partial curing and irradiation partial curing.
11. A conductive mesh touch sensor comprising:
a transparent substrate;
a layer of catalytic photoresist patterns made of a catalytic photoresist composition, the catalytic photoresist composition including a photoresist and catalytic nanoparticles;
a metal conductive layer with conductive patterns forming a conductive mesh over the layer of catalytic photoresist patterns;
a metal passivation layer over the metal layer;
a clear protective coating over the metal passivation layer; and
a flex cable provided over the clear protective coating.
12. The touch sensor of claim 11 , wherein the metal conductive layer includes copper and the metal passivation layer includes palladium.
13. The touch sensor of claim 12 , wherein the clear protective coating covers the conductive mesh and a bond pad area of the touch sensor.
14. The touch sensor of claim 13 , wherein the flex cable is attached to the bond pad with adhesive, the adhesive comprising a plurality of solder particles that penetrate the clear protective coating.
15. The touch sensor of claim 11 , wherein the clear protective coating includes monofunctional acrylic oligomers.
16. The touch sensor of claim 12 , wherein the clear protective coating has a thickness of between 1 to 3 micrometers.
17. A touchscreen, comprising:
a display device;
a touch sensor over the display device;
a cover lens; and,
an optically clear adhesive or resin between the touch sensor and the cover lens;
wherein the touch sensor comprises: a transparent substrate; a layer of catalytic photoresist patterns of a catalytic photoresist composition, the catalytic photoresist composition including a photoresist and catalytic nanoparticles; a metal conductive layer with conductive patterns over the layer of catalytic photoresist patterns; a metal passivation layer over the metal layer; and a transparent protective layer over the metal passivation layer.
18. The touchscreen of claim 17 , wherein the clear protective coating includes monofunctional acrylic oligomers.
19. The touchscreen of claim 17 , wherein the transparent protective layer covers the metal passivation layer and a bond pad area of the touch sensor.
20. The touchscreen of claim 19 , further comprising a flex cable attached to the bond pad with adhesive, the adhesive comprising a plurality of solder particles that penetrate the transparent protective layer.
21. The touchscreen of claim 17 , wherein transparent protective layer comprises partially cured monofunctional acrylic oligomers.
22. A touch sensor, comprising:
a transparent substrate;
a metal conductive layer with conductive patterns and bond pads formed over the transparent substrate;
a metal passivation layer over the metal layer;
a transparent protective layer over the metal passivation layer and the bond pads;
a flex cable attached to the bond pad and having a plurality of solder particles that penetrate the transparent protective layer and contact the bond pads.