Substrate with insulating layer

Patent metadata

Field	Value
Publication number	US-2016345451-A1
Application number	US-201415031594-A
Country	US
Kind code	A1
Filing date	Feb 14, 2014
Priority date	Feb 14, 2014
Publication date	Nov 24, 2016
Grant date	—

Abstract

A substrate with a Micro-Arc Oxidation (MAO) layer or an electrophoretic deposition (ED) layer on a first side of the substrate and an electrically insulating layer on a second side of the substrate.

First claim

What is claimed is:

1 . A method of treating a substrate comprising a first surface and a second surface, the first surface and the second surface being electrically conductive surfaces on opposite sides of the substrate, the method comprising applying an electrically insulating coating to the first surface of the substrate and then performing Micro-Arc Oxidation (MAO) or electrophoretic deposition (ED) on the second surface of the substrate; wherein the electrically insulating coating covers at least 80% of the first surface of the substrate.

2 . The method of claim 1 wherein the electrically insulating coating is applied by spray coating, film transfer, physical vapor deposition or printing.

3 . The method of claim 1 wherein the electrically insulating coating covers substantially the entire first surface of the substrate so that after performing MAO or ED, the first surface is not covered with an MAO or ED layer.

4 . The method of claim 1 wherein the substrate has an edge connecting the first surface and the second surface and wherein the insulating coating is applied to said edge as well as to the first surface of the substrate.

5 . The method of claim 1 wherein after performing MAO or ED, at least 90% of the second surface is covered with a MAO layer or an ED layer.

6 . The method of claim 1 wherein the electrically insulating layer comprises a material selected from the group comprising: polyimides, ABS (Acrylonitrile, butadiene and styrene), polyacetate, polyacrylics, nylon, epoxy, fluoropolymer, Neoprene, PEEK (PolyEtherEther-Ketone), PET (Polyethylene terephthalate), phenolics, polycarbonate, polyester, polyolefins, polystyrene, polysulfones, polyurethanes, PVC, silicone rubber, PEI (polyetherimide) and low dielectric constant materials.

7 . The method of claim 1 wherein MAO is carried out with an electrolyte including a material selected from the group comprising: silicate, aluminate, sulfate, aluminum powder, aluminum alloy powder, zinc oxide, sodium hydroxide, potassium hydroxide, potassium fluoride, aluminum hydroxide, borate, carbonate, rare earth element and aluminum oxide (Al 2 O 3 ).

8 . The method of claim 1 wherein the electrophoretic deposition comprises a polymer in combination with particles selected from the group comprising inorganic and metallic particles.

9 . A casing for an electronic device comprising a substrate, a Micro-Arc Oxidation (MAO) layer or an electrophoretic deposition (ED) layer on a first side of the substrate and an electrically insulating layer on a second side of the substrate; the first side of the substrate facing an exterior of the casing and the second side of the substrate facing an interior of the casing.

10 . The casing of claim 9 wherein the insulating layer comprises a material selected from the group comprising: polyimides, ABS (Acrylonitrile, butadiene and styrene), polyacetates, polyacrylics, nylon, epoxy, fluoropolymers, Neoprene, PEEK (PolyEtherEther-Ketone), PET (Polyethylene terephthalate), phenolics, polycarbonates, polyesters, polyolefins, polystyrene, polysulfones, polyurethane, PVC, silicone rubber, PEI (polyetherimide) and low dielectric constant materials.

11 . The casing of claim 9 wherein the MAO layer comprises a metal oxide which has an at least partially crystalline structure.

12 . The casing of claim 9 wherein the substrate comprises a plurality of electrically conductive layers between the ED or MAO layer and the electrically insulating layer.

13 . A casing for an electronic device comprising a substrate having a surface area, a first portion of the surface area of the substrate being covered with an electrically insulating layer and a second portion of the surface area of the electrically conductive substrate being covered with a Micro-Arc Oxidation (MAO) layer or an electrophoretic deposition (ED) layer, the first portion comprising at least 45% of the surface area of the substrate.

14 . The casing of claim 13 wherein the first portion of the surface area includes an inside surface of the casing and the second portion of the surface area includes an outside surface of the casing.

15 . The casing of claim 13 wherein the substrate comprises a light metal or light metal alloy selected from the group comprising Aluminum, Magnesium, Lithium, Titanium, Zinc and their alloys.

Assignees

• Hewlett Packard Development Co Lp

Inventors

• Wu Kuan-Ting
• Kang Yu-Chuan
• Huang Chung-Hung

Classifications

• C25D13/10

  characterised by the additives used {(not used, see C09D5/448)} · CPC title

• H05K5/04

  Metal casings · CPC title

• C09D5/4411

  Homopolymers or copolymers of acrylates or methacrylates · CPC title

• C09D5/443

  Polyepoxides · CPC title

• C25D15/00

  Electrolytic or electrophoretic production of coatings containing embedded materials, e.g. particles, whiskers, wires · CPC title