PROTECTING ANODIZED SURFACES DURING MANUFACTURING PROCESSES

• US 20190062939A1
• Filed: 08/24/2017
• Published: 02/28/2019
• Est. Priority Date: 08/24/2017
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: CURRAN, James A., PATERSON, Aaron D., BURKE, William D.
• Granted Patent: US 10,443,145 B2
• Time in Patent Office: Days
• CPC Class Codes: B44C 1/228 by laser radiation
• CPC Class Codes: C23C 22/58 Treatment of other metallic material
• CPC Class Codes: C25D 11/18 After-treatment, e.g. pore-sealing
• CPC Class Codes: C25D 11/22 for colouring layers
• CPC Class Codes: C25D 11/243 using organic dyestuffs
• CPC Class Codes: C25D 11/246 for sealing layers
• CPC Class Codes: G06F 1/16 Constructional details or arrangements
• CPC Class Codes: G06F 1/1613 for portable computers cooling arrangements therefor G06F1/203; constructional details or arrangements for pocket calculators, electronic agendas or books G06F15/0216; constructional details of portable telephone sets: with several bodies H04M1/0202
• CPC Class Codes: G06F 1/1656 Details related to functional adaptations of the enclosure, e.g. to provide protection against EMI, shock, water, or to host detachable peripherals like a mouse or removable expansions units like PCMCIA cards, or to provide access to internal components for maintenance or to removable storage supports like CDs or DVDs, or to mechanically mount accessories mounting of accessories to a computer display G06F1/1607; display hoods G06F1/1603; cooling arrangements for portable computers G06F1/203
• CPC Class Codes: H05K 5/0086 portable, e.g. battery operated apparatus casings for switching devices H01H9/02
• CPC Class Codes: H05K 5/04 Metal casings

Abstract

Treatments for anodic coatings that provide improved resistance to staining and cracking during various manufacturing processes are described. According to some embodiments, the methods include placing the anodic coatings in partially sealed states by sealing only the outermost portions of the anodic coatings, which protect the outer surfaces of the anodic coatings from contamination and staining. Inner portions of the anodic coatings are left unsealed, thereby making the anodic coatings more compliant and resistant to cracking when exposed to manufacturing processes, even those that involve exposure to high temperatures or high mechanical stress. Subsequent to the processing, another sealing process can be implemented to fully seal the anodic coatings so that they provide good corrosion and wear resistance.

Claims

1. A part, comprising:

an anodic film on a metal substrate, the anodic film having a first section and a second section,

wherein the first section is characterized as having a substantially fully sealed pore, and

wherein the second section is characterized as having a partially sealed pore.

2. The part of claim 1, wherein a surface of the second section has a polymer adhered thereto.

3. The part of claim 1, wherein the first section is laterally adjacent to the second section.

4. The part of claim 1, wherein the second section is characterized as having an electrical impedance measurement that is at least ten times that of the first section.

5. The part of claim 4, wherein the electrical impedance measurement of the first section is about 30 μ

S or less.

6. The part of claim 1, wherein the substantially fully sealed pore has a colorant infused therein.

7. The part of claim 1, wherein the partially sealed and the substantially fully sealed pores are characterized as having diameters ranging between about 10 nanometers and about 30 nanometers.

8. The part of claim 1, wherein the part is a housing for an electronic device.

9. The part of claim 1, wherein an exterior portion of the partially sealed pore includes a metal oxide hydroxide plug and an interior portion of the partially sealed pore includes a non-continuous metal oxide hydroxide structure.

10. The part of claim 1, wherein exterior portions of the partially and fully sealed pores include silicon, and interior portions of the partially and fully sealed pores are substantially free of silicon.

11. A method of treating a part having an anodic film on a metal substrate, the method comprising:

partially sealing the anodic film;

performing one or more manufacturing operations on the part; and

substantially fully sealing at least a section of the anodic film.

12. The method of claim 11, wherein partially sealing the anodic film includes using a first hydrothermal sealing process, and substantially fully sealing the anodic film includes using a second hydrothermal sealing process.

13. The method of claim 12, wherein the first hydrothermal sealing process includes using an aqueous solution containing nickel, and the second hydrothermal sealing process includes using an aqueous solution substantially free of nickel.

14. The method of claim 11, wherein the anodic film includes a first section having a first pore and a laterally adjacent second section having a second pore, wherein the one or more manufacturing operations include covering an exposed surface of the first section such that the first pore remains partially sealed after substantially fully sealing the second pore.

15. The method of claim 14, wherein covering the exposed surface of the first section includes thermally bonding a polymer material to the exposed surface.

16. The method of claim 14, wherein the one or more manufacturing operations include laser marking an interface region between the anodic film and the metal substrate.

17. The method of claim 11, wherein partially sealing the anodic film includes applying a silicate layer on an exterior surface of the anodic film, wherein fully sealing the anodic film includes using a hydrothermal sealing process.

18. A part, comprising:

an anodic film integrally bonded to a metal substrate at an interface and having an outer surface opposite the interface, wherein an outermost one micrometer of the anodic film is characterized as having a nickel concentration of at least 20 weight %, and an interior portion of the anodic film between the outermost one micrometer and the interface is characterized as having a nickel concentration of no more than about 1 weight %.

19. The part of claim 18, wherein the anodized part includes a first section and a second section, wherein the first section is characterized as having a substantially fully sealed pore, and the second section is characterized as having a partially sealed pore.

20. The part of claim 19, wherein the second section is characterized as having an electrical impedance that is at least ten times that of the first section.