Patterned substrates with darkened conductor traces

• US 9,736,928 B2
• Filed: 02/01/2012
• Issued: 08/15/2017
• Est. Priority Date: 02/02/2011
• Status: Expired due to Fees

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: McGee, Kari A., Luo, Hui, Kolb, William B., Maki, Stephen P., Zu, Lijun, Frey, Matthew H., Yu, Ta-Hua, Kolb, Brant U., David, Moses M.
• Primary Examiner(s): Ahmed, Sheeba
• Application Number:
  US13/979,710
• Publication Number:
  US 20130299214A1
• Time in Patent Office: 2,022 Days
• Field of Search: None
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: B82Y 99/00 Subject matter not provided for in other groups of this subclass
• CPC Class Codes: G02B 1/116 including electrically conducting layers
• CPC Class Codes: G02B 27/142 Coating structures, e.g. thin films multilayers
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• CPC Class Codes: H03K 17/962 Capacitive touch switches
• CPC Class Codes: H05K 1/0274 Optical details, e.g. printed circuits comprising integral optical means H05K1/0269 takes precedence; coupling light guides with opto-electronic components G02B6/42
• CPC Class Codes: H05K 1/0306 Inorganic insulating substrates, e.g. ceramic, glass
• CPC Class Codes: H05K 1/09 Use of materials for the conductive, e.g. metallic pattern
• CPC Class Codes: H05K 2201/0108 Transparent
• CPC Class Codes: H05K 2201/09681 Mesh conductors, e.g. as a ground plane
• CPC Class Codes: H05K 3/061 Etching masks
• CPC Class Codes: H05K 3/4644 by building the multilayer layer by layer, i.e. build-up multilayer circuits making via holes in the insulating layers H05K3/0011; special circuit boards as base or core whereon the multilayer is built H05K3/4602
• CPC Class Codes: H05K 9/0086 comprising a single discontinuous metallic layer on an electrically insulating supporting structure, e.g. metal grid, perforated metal foil, film, aggregated flakes, sintering
• CPC Class Codes: H05K 9/0096 for television displays, e.g. plasma display panel
• CPC Class Codes: Y10S 977/755 Nanosheet or quantum barrier/well, i.e. layer structure having one dimension or thickness of 100 nm or less

Abstract

The present disclosure provides an article having (a) a substrate having a first nanostructured surface that is antireflective when exposed to air and an opposing second surface; and (b) a conductor micropattern disposed on the first surface of the substrate, the conductor micropattern formed by a plurality of traces defining a plurality of open area cells. The micropattern has an open area fraction greater than 80% and a uniform distribution of trace orientation. The traces of the conductor micropattern have a specular reflectance in a direction orthogonal to and toward the first surface of the substrate of less than 50%. Each of the traces has a width from 0.5 to 10 micrometer. The articles are useful in devices such as displays, in particular, touch screen displays useful for mobile hand held devices, tablets and computers. They also find use in antennas and for EMI shields.

Claims

1. An article comprising:

a substrate having a first nanostructured surface that is antireflective when exposed to air and an opposing second surface; and

a conductor micropattern disposed on the first surface of the substrate, the conductor micropattern formed by a plurality of traces defining a plurality of open area cells,

wherein the micropattern has an open area fraction greater than 80% and a uniform distribution of trace orientation;

wherein the traces of the conductor micropattern have a specular reflectance in a direction orthogonal to and toward the first surface of the substrate of less than 50%; and

wherein each of the traces has a width from 0.5 to 10 micrometer.

2. The article of claim 1, wherein the nanostructured surface comprises nanofeatures having a height of from 50 to 500 nanometers.

3. The article of claim 1, wherein the nanostructured surface comprises nanofeatures having a height-to-width ratio of 2 to 1.

4. The article of claim 1, wherein the nanostructured surface has a reflectance of between 0.05 to 1%.

5. The article of claim 1, wherein the nanostructured surface has a transmitted haze of between 0.1 to 1%.

6. The article of claim 1, wherein the substrate is transparent.

7. The article of claim 1, wherein each of the conductor micropattern traces has a radius of curvature of less than 1 centimeter.

8. The article of claim 1, wherein the uniform distribution of trace orientation for the micropattern has a standard deviation of measured frequency per two degree bin of less than three.

9. The article of claim 1, wherein the trace comprises a material selected from the group consisting of gold, silver, palladium, platinum, aluminum, copper, molybdenum, nickel, tin, tungsten, alloys, and combinations thereof.

10. The article of claim 1, wherein the conductor micropattern has a non-repeating cell geometry.

11. The article of claim 1, wherein the conductor micropattern has cells that do not lie on a repeating array of positions.

12. The article of claim 1, wherein the specular reflectance is less than 20%.

13. The article of claim 1, wherein the specular reflectance is less than 10%.

14. The article of claim 1 having at least 90% transmission in visible light and less than 5% haze.

15. The article of claim 1, wherein the nanostructured surface comprises a matrix and a nanoscale dispersed phase, and wherein the nanstructured surface is a random nanostructured anisotropic surface.

16. The article of claim 15, wherein the matrix comprises a hardcoat comprising nanoparticles of SiO₂, ZrO₂ and combinations thereof dispersed in a crosslinkable matrix comprising multi(meth)acrylate, polyester, epoxy, fluoropolymer, urethane, siloxane, or blends or copolymers thereof.

17. The article of claim 15, wherein the nanoscale dispersed phase comprises nanoparticles of SiO₂, ZrO₂, TiO₂, ZnO, Al₂O₃, calcium carbonate, magnesium silicate, indium tin oxide, antimony tin oxide, poly(tetrafluoroethylene), carbon and combinations thereof.

18. The article of claim 15, wherein the nanoparticles have an average particle size of less than about 100 nanometers.

19. The article of claim 15, wherein the matrix comprises a polymer selected from the group consisting of polycarbonate, poly(meth)acrylate, polyester, nylon, siloxane, fluoropolymer, urethane, epoxy, cyclic olefin copolymer, triacetate cellulose, diacrylate cellulose or blends or copolymers thereof.

20. The article of claim 15, wherein the matrix comprises an inorganic material selected from the group of silicon oxide and tungsten carbide.

21. The article of claim 15, wherein the substrate comprises a cross-linkable material selected from multi(meth)acrylate, polyester, epoxy, fluoropolymer, urethane, siloxane, or blends or copolymers thereof.

36. The article of claim 1, wherein the nanostructured surface is a random anisotropic nanostructured surface.

22. An article comprising:

a substrate having opposing first and second surfaces; and

a conductor micropattern disposed on the first surface of the substrate, the conductor micropattern comprising a plurality of traces defining a plurality of cells,

wherein the conductor micropattern has an open area fraction greater than 80% and a uniform distribution of trace orientation; and

each of the traces has a trace width from 0.5 to 10 micrometer, and

wherein the conductor micropattern comprises in sequence a semi-reflective metal, a transparent layer, and a reflective layer disposed on the transparent layer.

23. The article of claim 22, wherein the semi-reflective material is selected from the group consisting of titanium, chromium, aluminum, nickel, copper, gold, molybdenum, platinum, rhodium, silver, tungsten, cobalt, iron, germanium, hafnium, palladium, rhenium, vanadium, silicon, selenium, tantalum, yttrium, zirconium and combinations and alloys thereof.

24. The article of claim 22, wherein the transparent material is selected from the group consisting of acrylic polymers, SiO₂, Al₂O₃, ZrO₂, TiO₂, HfO₂, Sc₂O₃, La₂O₃, ThO₂, Y₂O₃, CeO₂, MgO, Ta₂O₅ and combinations thereof.

25. The article of claim 22, wherein the reflective layer is selected from the group consisting of gold, silver, palladium, platinum, aluminum, copper, molybdenum, nickel, tin, tungsten, alloys, and combinations thereof.

26. The article of claim 22, wherein each of the conductor micropattern traces has a radius of curvature of less than 1 centimeter.

27. The article of claim 22, wherein the uniform distribution of trace orientation for the micropattern has a standard deviation of measured frequency per two degree bin of less than three.

28. The article of claim 22, wherein the conductor micropattern has a non-repeating cell geometry.

29. The article of claim 22, wherein the conductor micropattern has cells that do not lie on a repeating array of positions.

30. The article of claim 22, wherein traces have a specular reflectance of less than 20% at normal incidence and in a direction oriented toward the first surface of the substrate.

31. The article of claim 22, wherein the traces have a specular reflectance of less than 10% at normal incidence and in a direction oriented toward the first surface of the substrate.

32. The article of claim 22, wherein the traces have a specular reflectance of less than 50% at normal incidence and in a direction oriented toward the first surface of the substrate.

33. The article of claim 22, wherein the traces have a specular reflectance of less than 20% at normal incidence and in a direction oriented away from the first surface of the substrate.

34. The article of claim 22, wherein the traces have a specular reflectance of less than 10% at normal incidence and in a direction oriented away the first surface of the substrate.

35. The article of claim 22, wherein the traces have a specular reflectance of less than 50% at normal incidence and in a direction oriented away the first surface of the substrate.