Method for the formation of multi-layer paint films

Patent metadata

Field	Value
Publication number	US-9962730-B2
Application number	US-201113994874-A
Country	US
Kind code	B2
Filing date	Nov 23, 2011
Priority date	Dec 17, 2010
Publication date	May 8, 2018
Grant date	May 8, 2018

Abstract

Disclosed is a method for the formation of multi-layer paint films with the omission of a mid-coat paint coating process. The method comprises the use of a particular aqueous colored paint (A) comprising a prescribed amount of specified titanium oxide that has been compounded, The resulting multi-layer paint films have a very bright paint color, and especially a white or light-colored color, and have excellent concealing properties. The aqueous colored paint (A) is characterized by containing from 50 to 60 mass % with respect to the whole paint solid fraction of titanium oxide of specific surface area not more than 13 m 2 /g.

First claim

The invention claimed is:

1. A method for the formation of a multi-layer paint film comprising a colored paint film layer and a clear paint film layer, comprising
forming an electro-deposition coating by an electro-deposition coating process on a base material so as to form a cured electro-deposited paint film comprising an L-value of from 30 to 50,
coating over the cured electro-deposited paint film with a first colored paint coating process comprising a first aqueous colored paint (A) comprising from 50 to 60 mass % with respect to the whole paint solid fraction of a titanium oxide of a specific surface area not more than 13 m 2 /g so as to form a first colored paint film,
carrying out a preliminary heating process with the first colored paint film after an interval of 3 to 8 minutes from the application of the coating to produce a preliminary heated first colored paint film,
carrying out a clear coating process in which a coating of a clear paint (C) is applied over the preliminary heated first colored paint film to form a clear paint film, and
heating and curing the clear paint film and the preliminary heated first colored paint film at the same time,
wherein the L-value of the first colored paint film is 85 or above and the difference between the paint solid fraction content of the first colored paint film 2 minutes after coating the first aqueous colored paint (A) and the paint solid fraction content of the first aqueous colored paint (A) immediately before coating is from 4 to 11 mass %.

2. The method of claim 1 , wherein the first aqueous colored paint (A) is coated directly on the surface of the cured electro-deposited paint film.

3. The method of claim 1 , wherein the first aqueous colored paint (A) is coated directly on the surface of the cured electro-deposited paint film, and not on the surface of another paint film on the surface of the cured electro-deposited paint film.

4. The method of claim 1 , wherein the L-value of the first colored paint film is an L-value measured at an angle of 0° to a line perpendicular to a surface of the first colored paint film.

5. A method for the formation of a multi-layer paint film comprising a colored paint film layer and a clear paint film layer comprising:
forming an electro-deposition coating by an electro-deposition coating process on a base material so as form a cured electro-deposited paint film comprising an L value of from 30 to 50,
coating over the cured electro-deposited paint film with a first colored paint coating process comprising a first aqueous colored paint (A) comprising from 50 to 60 mass % with respect to the whole paint solid fraction of a titanium oxide of a specific surface area not more than 13 m 2 /g so as to form a first colored paint film,
coating over the first colored paint film with a second colored paint coating process comprising a second aqueous colored paint (B) comprising a glitter pigment that is not an aluminum pigment to form a second colored paint film,
carrying out a preliminary heating process in which the first colored paint film and the second colored paint film are subjected to a preliminary heating after an interval of 3 to 8 minutes from the application of the second coating to produce a preliminary heated first colored paint film and a preliminary heated second colored paint film,
carrying out a clear coating process in which a coating of a clear paint (C) is applied over the preliminary heated second colored paint film to form a clear paint film, and
heating and curing at the same time the clear paint film, the preliminary heated first colored paint film, and the preliminary heated second colored paint film,
wherein the L-value of the first colored paint film is 85 or above and the difference between the paint solid fraction content of the first colored paint film 2 minutes after coating the first aqueous colored paint (A) and the paint solid fraction content of the first aqueous colored paint (A) immediately before coating is from 4 to 11 mass %.

6. The method for the formation of a multi-layer paint film of claim 5 , wherein said preliminary heating process comprises carrying out a preliminary heating of the first colored paint film which has been formed by the first colored paint coating process between the first colored paint coating process and the second colored paint coating process,
wherein the preliminary heating of the first colored paint film is carried out after an interval of 3 to 8 minutes from the application of the first coating.

7. The method of claim 5 , wherein the first aqueous colored paint (A) is coated directly on the surface of the cured electro-deposited paint film.

8. The method of claim 5 , wherein the first aqueous colored paint (A) is coated directly on the surface of the cured electro-deposited paint film, and not on the surface of another paint film on the surface of the cured electro-deposited paint film.

Assignees

• Mizuno Shigeyuki
• Kojima Keisuke
• Kaneko Katsuyoshi
• Basf Japan Ltd
• Honda Motor Co Ltd

Inventors

• Mizuno Shigeyuki
• Kojima Keisuke
• Kaneko Katsuyoshi

Classifications

• B05D2601/24

  Titanium dioxide, e.g. rutile · CPC title

• B05D2451/00

  Type of carrier, type of coating (Multilayers) · CPC title

• B05D7/534 Primary

  the first layer being let to dry at least partially before applying the second layer (B05D7/538 takes precedence) · CPC title

• B05D3/007 Primary

  After-treatment · CPC title

• B05D2401/20

  Aqueous dispersion or solution · CPC title