US 12,129,401 B2
Cracks-controllable coating and preparation method thereof
Zihe Hu, Shanghai (CN)
Assigned to Bauhinia Coatings Manufacturing (Shanghai) Co., LTD., Shanghai (CN)
Filed by Bauhinia Coatings Manufacturing (Shanghai) Co., LTD., Shanghai (CN)
Filed on Dec. 11, 2023, as Appl. No. 18/535,890.
Claims priority of application No. 202211613011.8 (CN), filed on Dec. 15, 2022.
Prior Publication US 2024/0287327 A1, Aug. 29, 2024
Int. Cl. C09D 5/28 (2006.01); C09D 5/00 (2006.01); C09D 175/04 (2006.01)
CPC C09D 5/28 (2013.01) [C09D 5/002 (2013.01); C09D 175/04 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A method of preparing a crack-controllable coating, comprising:
(1) spraying at least one coat of a colored reaction-curable primer on a substrate followed by drying to form a first primer layer;
(2) spraying a first one-component crackle coating on the first primer layer followed by drying to form a first crackle coating layer;
(3) spraying one or two coats of a transparent reaction-curable primer on the first crackle coating layer followed by drying to form a second primer layer;
(4) spraying a second one-component crackle coating on the second primer layer followed by drying to form a second crackle coating layer, wherein the second one-component crackle coating is transparent; and
(5) spreading a colorant on a surface of the second crackle coating layer to allow the colorant to be embedded in a crack in the second crackle coating layer; wiping the second crackle coating layer to remove excess colorant followed by drying; and spraying a polyurethane varnish on the second crackle coating layer followed by drying to obtain the crack-controllable coating;
wherein in the step (2), a spraying amount of the first one-component crackle coating is 6-8 m2/kg; a thickness of the first crackle coating layer is 30-40 μm; the drying is performed to allow through drying of the first one-component crackle coating; and the first one-component crackle coating comprises a white one-component crackle coating, and the white one-component crackle coating is a white nitro crackle lacquer, a white acrylic crackle lacquer or a combination thereof;
in the step (4), a spraying amount of the second one-component crackle coating is 12-15 m2/kg; a thickness of the second crackle coating layer is 15-25 μm; the drying is performed to allow through drying of the second one-component crackle coating; and the second one-component crackle coating comprises a transparent one-component crackle coating, and the transparent one-component crackle coating is a transparent nitro crackle lacquer, a transparent acrylic crackle coating or a combination thereof;
the step (1) further comprises:
testing a surface drying time and a through drying time of the colored reaction-curable primer; wherein the drying is performed at 5-35° C. and a humidity of 30%-75%, and a drying time is 1.5-2.5 times the surface drying time of the colored reaction-curable primer and 35%-45% of the through drying time of the colored reaction-curable primer; and
the step (3) further comprises:
testing a surface drying time and a through drying time of the transparent reaction-curable primer; wherein the drying is performed at 5-35° C. and a humidity of 30%-75%, and a drying time is 1.5-2.5 times of the surface drying time of the transparent reaction-curable primer and 35%-45% of the through drying time of the transparent reaction-curable primer.