Touch screen panel with surface friction modification
Embodiments enable forming a friction modified touch sensitive surface on a touch screen panel. In particular, the touch sensitive surface is augmented with two friction modifying materials that are interspersed with one another according to a predetermined pattern on the surface of the touch screen panel as a monomolecular layer. In an embodiment, The materials have indices of refraction that differ from each other by more than 0.10. In another embodiment, the materials have a kinetic coefficient of friction in one or the other range, respectively, of between 0.01 and 0.05, or between 0.06 and 0.1, said kinetic coefficients of friction being measured against printing paper that has a kinetic coefficient of friction of 0.17 with itself. In another embodiment, the materials have a water contact angle of greater than 90 degrees, and an oil contact angle of greater than 30 degrees as measured with n-hexadecane.
1. A touch screen panel including a friction modified touch sensitive surface, the friction modified touch sensitive surface comprising:
an outer surface of the touch screen panel, the outer surface including a touch sensitive area;
a first friction modifying material; and
a second friction modifying material, wherein the first and second friction modifying materials are interspersed with one another according to a predetermined pattern as a mono-molecular layer on the outer surface, and wherein the first friction modifying material is relatively more amorphous than the second friction modifying material.
2. The touch screen panel of claim 1 , wherein a difference in refractive indexes of the first and second friction modifying materials is greater than 0.10.
3. The touch screen panel of claim 2 , wherein the first friction modifying material has a kinetic coefficient of friction of between 0.01 and 0.05, the second friction modifying material has a kinetic coefficient of friction between 0.06 and 0.10, wherein the kinetic coefficients of friction of the first and second friction modifying materials are measured against printing paper that has a kinetic coefficient of friction of 0.17 with itself.
4. The touch screen panel of claim 1 , wherein the first and second friction modifying materials have a water contact angle of greater than 90 degrees.
5. The touch screen panel of claim 1 , wherein the first and second friction modifying materials have an oil contact angle of greater than 30 degrees as measured with n-hexadecane.
6. The touch screen panel of claim 1 , wherein the predetermined pattern comprises: a Penrose tiling pattern;
a white noise pattern;
a blue noise pattern; or a plurality of sub-patterns, each sub-pattern being adjacent to at least one other sub-pattern wherein transitions between adjacent sub-patterns are substantially undetectable.
7. The touch screen panel of claim 6 , wherein the predetermined pattern has a feature size greater than 200 microns.
8. A method of forming a friction modified touch sensitive surface on an outer surface of a touch screen panel, comprising:
depositing a layer of a first friction modifying material on the outer surface;
depositing a mask layer according to a predetermined pattern on the layer of first friction modifying material;
removing the first friction modifying material from unmasked areas of the outer surface;
depositing a layer of a second friction modifying material on the outer surface; and
removing the mask layer;
wherein the first and second friction modifying materials are chosen to have a kinetic coefficient of friction in one or the other range, respectively, of between 0.01 and 0.05, or between 0.06 and 0.1, said kinetic coefficient of friction being measured against printing paper that has a kinetic coefficient of friction of 0.17 with itself.
9. The method of claim 8 , wherein the first friction modifying material is relatively more amorphous than the second friction modifying material.
10. The method of claim 8 , wherein a difference in refractive indexes of the first and second friction modifying materials is greater than 0.1.
11. The method of claim 8 , wherein the first and second friction modifying materials have a water contact angle of greater than 90 degrees.
12. The method of claim 8 , wherein the first and second friction modifying materials have an oil contact angle of greater than 30 degrees as measured with n-hexadecane.
13. The method of claim 8 , wherein the predetermined pattern comprises: a penrose tiling pattern;
a white noise pattern;
a blue noise pattern; or a plurality of sub-patterns, each sub-pattern being adjacent to at least one other sub-pattern wherein transitions between adjacent sub-patterns are substantially undetectable.
14. The method of claim 8 , wherein the layers of the first and second friction modifying materials are deposited as mono-molecular layers.
15. A touch screen computing device, comprising:
a processor;
a touch screen panel coupled to the processor and including a friction enhanced touch sensitive surface comprising:
an outer surface of the touch screen panel, the outer surface including a touch sensitive area;
a first friction modifying material; and
a second friction modifying material, wherein the first and second friction modifying materials are interspersed with one another according to a predetermined pattern as a mono-molecular layer on the outer surface, and wherein the first friction modifying material is relatively more amorphous than the second friction modifying material.
16. The touch screen computing device claim 15 , wherein a difference in refractive indexes of the first and second friction modifying materials is greater than 0.1.
17. The touch screen computing device of claim 16 , wherein the first friction modifying material has a kinetic coefficient of friction of between 0.01 and 0.05, the second friction modifying material has a kinetic coefficient of friction between 0.06 and 0.1, wherein the kinetic coefficients of friction of the first and second friction modifying materials are measured against printing paper that has a kinetic coefficient of friction of 0.17 with itself.
18. The touch screen computing device of claim 15 , wherein the first and second friction modifying materials have a water contact angle of greater than 90 degrees.
19. The touch screen computing device of claim 15 , wherein the first and second friction modifying materials have an oil contact angle of greater than 30 degrees as measured with n-hexadecane.
20. The touch screen computing device of claim 15 , wherein the predetermined pattern comprises: a Penrose tiling pattern;
a white noise pattern;
a blue noise pattern;
or a plurality of sub-patterns, each sub-pattern being adjacent to at least one other sub-pattern wherein transitions between adjacent sub-patterns are substantially undetectable.