Method for manufacturing cover member, and cover member structure

Patent metadata

Field	Value
Publication number	US-2022004231-A1
Application number	US-202117475526-A
Country	US
Kind code	A1
Filing date	Sep 15, 2021
Priority date	Mar 18, 2019
Publication date	Jan 6, 2022
Grant date	—

Abstract

A method for manufacturing a cover member for electronic devices according to certain embodiments of the present disclosure may comprise: a step for forming a magnesium plate; a step for performing primary CNC processing on the magnesium plate using a predetermined cutting oil; a step for performing a primary pretreatment on the magnesium plate using chromate or micro arc oxidation (MAO); a step for performing a primary surface-treatment on the magnesium plate by bake-coating or electrodeposition coating; a step for performing secondary CNC processing on a first region of the magnesium plate using an alcohol-containing cutting oil; a washing and drying step; a step for performing a secondary pretreatment for preventing oxidation on the first region; and a step for performing a secondary surface-treatment on the first region by bake-coating or electrodeposition coating.

First claim

What is claimed is:

1 . A method of manufacturing a cover member of an electronic device, the method comprising:
shaping a plate comprising magnesium; performing primary computer numerical control (CNC) machining on the magnesium plate using a predetermined cutting oil; performing a primary pretreatment on the magnesium plate using a chromate or micro arc oxidation (MAO); performing a primary surface treatment on the magnesium plate by high temperature baking paint or electrodeposition painting; performing secondary CNC machining on one region of the magnesium plate using a cutting oil containing alcohol; washing and drying the magnesium plate; performing a secondary pretreatment for preventing oxidation in the one region; and performing a secondary surface treatment by high temperature baking paint or electrodeposition painting in the one region.

2 . The method of claim 1 , wherein, during the secondary CNC machining, the alcohol in the cutting oil is in an amount of at least 98% by weight based on a total weight of the cutting oil, and a gloss is provided through the secondary CNC machining.

3 . The method of claim 1 , wherein, during the secondary pretreatment, anti-oxidation coating is performed using a zirconium-based coating agent in the one region, and in the anti-oxidation coating, a transparent coating layer is formed to provide outward a metallic texture of the magnesium plate.

4 . The method of claim 3 , wherein, in the secondary surface treatment, anionic electrodeposition painting using a material including an acrylic resin and an organic pigment is performed.

5 . The method of claim 1 , wherein washing and drying the magnesium plate includes:
washing the magnesium plate using a washing solution containing alcohol; performing primary drying to remove the alcohol by air blow; and performing secondary drying by massaging a surface of the magnesium plate using a dry fabric.

6 . The method of claim 5 , further comprising hot air drying is additionally performed at 100 to 250 degrees C. for 1 min to 3 min after the secondary drying.

7 . The method of claim 1 , wherein the primary CNC machining is performed using a water-soluble or oil-soluble cutting oil.

8 . The method of claim 1 further comprising:
drying the magnesium plate through ultrasonic cleaning before the primary pretreatment,
wherein, in the primary pretreatment, an opaque oxidation treatment is performed on the dried magnesium plate using the chromate or the micro arc oxidation (MAO).

9 . The method of claim 1 , wherein, in the primary surface treatment, the high temperature baking paint is performed through spraying using a material containing aluminum paste or a titanium dioxide (TiO 2 ) inorganic pigment.

10 . The method of claim 1 , further comprising:
performing packaging for movement after the drying and washing, wherein the packaging is performed in a vacuum packaging method in order to prevent oxidation by moisture in air.

11 . The method of claim 1 , further comprising:
performing hot air drying at 130 to 200 degrees C. after the secondary surface treatment.

12 . The method of claim 1 , further comprising:
performing inspection for checking a machined state of an exterior of the one region of the magnesium plate after the washing and drying.

13 . A cover member of an electronic device, the cover member comprising:
a plate comprising magnesium; a zirconium-based coating layer formed on at least one region of the plate; and a painted layer disposed on one surface of the coating layer and formed by anionic electrodeposition painting using a material including an acrylic resin and an organic pigment.

14 . The cover member of claim 13 , wherein the coating layer formed in the one region forms a transparent coating layer and provides an outward metallic texture to the plate.

15 . The cover member of claim 13 , wherein the plate comprises at least one of magnesium-lithium (Mg—Li) alloy, AZ31B, AZ91, and AZ91D.

Assignees

• Samsung Electronics Co Ltd

Inventors

• Kim Hyunsoo
• Lee Sookyu
• Lim Jaewoong

Classifications

• C25D13/22 Primary

  Servicing or operating {apparatus or multistep processes} · CPC title

• C25D13/20

  Pretreatment · CPC title

• C25D11/30

  of magnesium or alloys based thereon · CPC title

• C25D11/026

  Anodisation with spark discharge · CPC title

• C23C22/73

  characterised by the process · CPC title