# US 2013/0153428 A1 · Metal Surface and Process for Treating a Metal Surface > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0153428 A1 - Document ID: US20130153428A1 - Status: Published application - Kind: A1 - Application number: 13/332,288 - Filed: 2011-12-20 - Published: 2013-06-20 - Earliest claimed: 2011-12-20 - Assignees: Apple Inc. - Inventors: Jody R. AKANA; Peter N. RUSSELL-CLARKE; Masashige TATEBE - Web page: https://patentgrep.com/patent/US20130153428A1 ## CPC - C25D 11/022: {Anodisation on selected surface areas} - B44C 1/005: {by altering locally the surface material (surface treatment to obtain special artistic surface effects or finishes B44D5/00)} - C25D 11/12: Anodising more than once, e.g. in different baths - C25D 11/16: Pretreatment {, e.g. desmutting} - C25D 11/20: Electrolytic after-treatment - C25D 11/22: for colouring layers - C25D 11/243: {using organic dyestuffs} - C25D 11/246: {for sealing layers} - C25D 11/26: of refractory metals or alloys based thereon - C25D 11/30: of magnesium or alloys based thereon - C25D 11/34: of metals or alloys not provided for in groups C25D11/04 - C25D11/32 - C25D: PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR - B44C: PRODUCING DECORATIVE EFFECTS (processes for applying liquids or other fluent materials to surfaces, in general B05D; shaping of plastics or substances in a plastic state B29C; printing processes to produce transfer pictures B41M3/12; thermographic duplication or marking methods B41M5/00); MOSAICS; TARSIA WORK (imitation of mosaic or tarsia work patterns B44F11/04); PAPERHANGING {(labels G09F; multi-step processes for making paper labels or tags B31D1/02)} ## Abstract A surface treatment for metal surfaces can be used to create one or more desired effects, such as functional, tactile, or cosmetic effects. In one embodiment, the treatment involves selectively masking a portion of the surface using a photolithographic process. The mask can protect the masked portion of the surface during subsequent treatment processes such as texturizing and anodization. The mask can result in the creation of a surface having contrasting effects. A pattern can be formed by the contrasting effects in the shape of a distinct graphic, such as a logo or text. ## Claims ### Claim 1 A method of treating a metal surface of an article comprising: providing an article having a metal surface; applying a mask to a portion of the metal surface using a photolithographic process to form a masked portion and an unmasked portion; texturizing the metal surface such that the masked portion and unmasked portion of the metal surface have contrasting effects; and anodizing the metal surface. ### Claim 2 (depends on 1) The method of claim 1, wherein the act of applying a mask to a portion of the metal surface using a photolithographic process includes: applying a photoresist to the metal surface; covering a portion of the photoresist to form a covered photoresist portion and an uncovered photoresist portion; exposing the uncovered photoresist portion to a light source to develop the uncovered photoresist portion to form a developed photoresist portion and an undeveloped photoresist portion; removing the undeveloped photoresist portion from the metal surface; and heating the developed photoresist portion to form a photoresist mask. ### Claim 3 (depends on 2) The method of claim 2, wherein the light source is an ultraviolet light source. ### Claim 4 (depends on 1) The method of claim 1, wherein the act of applying a mask to a portion of the metal surface using a photolithographic process includes: applying a photoresist to the metal surface; covering a portion of the photoresist to form a covered photoresist portion and an uncovered photoresist portion; exposing the uncovered photoresist portion to a light source to render the uncovered photoresist portion soluble to a developer solution to form a soluble photoresist portion and an insoluble photoresist portion; removing the soluble photoresist portion from the metal surface with the developer solution; and heating the insoluble photoresist portion to form a photoresist mask. ### Claim 5 (depends on 1) The method of claim 1, wherein the act of masking a portion of the metal surface using a photolithographic process includes: applying a photoresist to the metal surface; using a laser beam to develop a portion of the photoresist into a mask to form a developed portion and an undeveloped photoresist portion; and removing the undeveloped photoresist portion from the metal surface. ### Claim 6 (depends on 1) The method of claim 1, wherein the act of texturizing the metal surface includes forcibly propelling a stream of abrasive material against the metal surface. ### Claim 7 (depends on 1) The method of claim 1, wherein the act of texturizing the metal surface includes sandblasting the metal surface. ### Claim 8 (depends on 1) The method of claim 1, wherein the act of texturizing the metal surface includes chemically etching the metal surface. ### Claim 9 (depends on 1) The method of claim 1, further comprising: removing the mask from the metal surface before anodizing the metal surface. ### Claim 10 (depends on 1) The method of claim 1, further comprising: removing the mask from the metal surface after anodizing the metal surface. ### Claim 11 (depends on 1) The method of claim 1, further comprising: removing the mask from the metal surface; and texturizing the metal surface a second time after the mask is removed. ### Claim 12 (depends on 1) The method of claim 1, further comprising polishing the metal surface after the metal surface is anodized. ### Claim 13 (depends on 1) The method of claim 1, wherein a pattern created by the contrasting effects is in the form of a logo. ### Claim 14 (depends on 1) The method of claim 1, wherein a pattern created by the contrasting effects is in the form of text. ### Claim 15 (depends on 1) The method of claim 1, further comprising: applying a second mask to a portion of the metal surface using a photolithographic process after the metal surface is anodized. ### Claim 16 (depends on 1) The method of claim 1, wherein the metal surface is aluminum. ### Claim 17 (depends on 1) The method of claim 1, wherein the article is a handheld electronic device housing. ### Claim 18 (depends on 1) The method of claim 1, wherein an oxide layer is formed during the act of anodizing the metal surface, the method further comprising: performing a metal deposition process to deposit a metal within the oxide layer. ### Claim 19 (depends on 1) The method of claim 1, further comprising: dyeing the metal surface after the act of anodizing the metal surface. ### Claim 20 (depends on 1) A metal surface treated according to the method of claim 1. ### Claim 21 An article of manufacture, comprising: a metal surface having a contrasting surface finish formed by a surface treatment process in which a mask is applied to a portion of the metal surface using a photolithographic process to form a masked portion and an unmasked portion, and wherein only the unmasked portion is texturized. ### Claim 22 (depends on 21) The article of claim 21, wherein only the unmasked portion is dyed. ### Claim 23 (depends on 22) The article of claim 22, wherein the metal surface is aluminum. ### Claim 24 A method of treating an aluminum surface of a component for an electronic device comprising: providing a component for an electronic device having an aluminum surface; selectively masking a portion of the aluminum surface by using a photolithographic process including: applying a photoresist to the aluminum surface; covering a portion of the photoresist to form a covered photoresist portion and an uncovered photoresist portion; exposing the uncovered photoresist portion to an ultraviolet light source to develop the uncovered photoresist portion to form a developed photoresist portion and an undeveloped photoresist portion; removing the undeveloped photoresist portion from the aluminum surface; and heating the developed photoresist portion into a photoresist mask to form a masked portion and an unmasked portion; abrasively blasting the aluminum surface such that a pattern is formed between the masked and unmasked portions of the aluminum surface; removing the mask; and anodizing the aluminum surface. ### Claim 25 (depends on 24) The method of claim 24, further comprising: dyeing the aluminum surface after the aluminum surface is anodized. ### Claim 26 (depends on 24) The method of claim 24, wherein an oxide layer is formed during the act of anodizing the aluminum surface, the method further comprising: performing a metal deposition process to deposit a metal within the oxide layer. ### Claim 27 (depends on 24) The method of claim 24, wherein the component for an electronic device is a housing for a handheld electronic device. ### Claim 28 (depends on 27) The method of claim 27, wherein the handheld electronic device is a tablet computer. ### Claim 29 (depends on 27) The method of claim 27, wherein the handheld electronic device is a phone.