Method of treating surface of metal base, metallic material treated by the surface treatment method, and method of coating the metallic material

Patent metadata

Field	Value
Publication number	US-11293102-B2
Application number	US-44026007-A
Country	US
Kind code	B2
Filing date	Sep 7, 2007
Priority date	Sep 8, 2006
Publication date	Apr 5, 2022
Grant date	Apr 5, 2022

Abstract

A method of treating the surface of a metal base which is conducted prior to cationic electrodeposition coating and is used for improving throwing power in the cationic electrodeposition coating; a metallic material treated by the surface treatment method; and a method of coating this metallic material.

First claim

The invention claimed is:

1. A surface treatment method for improving uniformity of a cathodic electrodeposition coating film, the method comprising the steps of:
treating a surface of a metal base material to form a rust-resistant film by applying to the surface of the metal base material a treatment composition comprising
at least one of zirconium ions or titanium ions;
at least one stabilizing agent selected from the group consisting of an amino acid compound, an aminocarboxylic acid compound, and a sulfonic acid compound; and
at least one adhesive imparting agent comprising an adhesive imparting resin comprising a polyamine compound having at least one constituent unit represented by the chemical formula

wherein in chemical formula (3), R 1 is an alkylene group having 1 to 6 carbon atoms, R 2 is a substituent group represented by one of the following chemical formulas (4) to (6), and R 3 is a hydroxyl group, an alkoxy group having 1 to 6 carbon atoms, or an alkyl group having 1 to 6 carbon atoms, and

in chemical formula (6), R 6 is a hydrogen atom, an aminoalkyl group having 1 to 6 carbon atoms or an alkyl group having 1 to 6 carbon atoms, and R 7 is hydrogen atom or an aminoalkyl group having 1 to 6 carbon atoms;
at least one step selected from the group consisting of
(d) contacting all or a part of the metal base material with a first oxidizing agent selected from the group consisting of nitrous acid, sulfurous acid, persulfate, bromic acid, an iodine compound, chloric acid, HMnO 4 , HVO 3 , H 2 MoO 4 , H 2 WO 4 , hydrogen peroxide and salts thereof after the surface treatment step, and
(e) contacting all or a part of the metal base material with a second oxidizing agent selected from the group consisting of nitrous acid, sulfurous acid, persulfate, bromic acid, an iodine compound, chloric acid, HMnO 4 , HVO 3 , H 2 MoO 4 , H 2 WO 4 , hydrogen peroxide and salts thereof, and thereafter washing all or a part of the treated metal base material with water after the surface treatment step; and

electropainting the metal base material with a cathodic electrodeposition coating material consisting of an amine-modified epoxy resin, a curing agent, and a sealing agent.

2. The surface treatment method according to claim 1 , wherein the treatment composition further comprises at least one polyvalent anion selected from the group consisting of phosphoric acid, phosphonic acid, lignin, tannic acid, a phenol compound, an amino acid, a polyacrylic acid, and a sugar.

3. The surface treatment method according to claim 1 , wherein the adhesive imparting agent further comprises a silicon-containing compound selected from the group consisting of silica, silicofluoride, a soluble silicate compound, silicate esters, alkyl silicates, and a silane coupling agent.

4. The surface treatment method according to claim 3 , wherein the silane coupling agent is at least one selected from the group consisting of an aminosilane having at least an amino group in a molecule, and a hydrolysis-polycondensate of the aminosilane, wherein
the treatment composition has a total amount of the zirconium and/or titanium ions of 10 ppm to 10,000 ppm based on metal element content,
the treatment composition has a total amount of the aminosilane and/or the hydrolysis-polycondensate of the aminosilane of 1 ppm to 2,000 ppm based on silicon element content, and
the treatment composition has a mass ratio of zirconium and/or titanium elements to silicon element contained in the aminosilane having at least an amino group in a molecule, the hydrolysis-polycondensate of the aminosilane, or both, of 0.5 to 500.

5. The surface treatment method according to claim 1 , wherein the adhesive imparting agent further comprises an adhesive imparting metal ion that is at least one metal ion selected from the group consisting of magnesium, zinc, calcium, aluminum, gallium, indium, copper, iron, manganese, nickel, cobalt, silver, and tin.

6. The surface treatment method according to claim 1 , wherein the adhesive imparting resin further comprises at least one member selected from the group consisting of a blocked isocyanate compound, and a melamine resin.

7. The surface treatment method according to claim 6 , wherein the polyamine compound further comprises at least one constitutional unit represented by the chemical formulas (1), and/or (2) shown below, and
the treatment composition has a mass ratio of zirconium and/or titanium elements to polyamine compound of 0.1 to 100

8. A surface treatment method according to claim 1 , wherein the treatment composition has a pH of 1.5 to 6.5.

9. A metal material treated with the surface treatment method according to claim 1 .

10. The surface treatment method according to claim 1 , wherein the treatment composition further comprises at least one polyvalent anion selected from the group consisting of phosphoric acid, phosphonic acid, lignin, tannic acid, an amino acid, a polyacrylic acid, and a sugar.

11. A surface treatment method for improving uniformity of a cathodic electrodeposition coating film, the method comprising the steps of:
treating a surface of a metal base material to form a rust-resistant film by applying to the surface of the metal base material a treatment composition comprising at least one of zirconium ions or titanium ions; at least one stabilizing agent selected from the group consisting of an amino acid compound, an aminocarboxylic acid compound, and a sulfonic acid compound; and at least one adhesive imparting agent comprising an adhesive imparting resin comprising a polyamine compound having at least one constituent unit represented by the chemical formula

wherein in chemical formula (3), R 1 is an alkylene group having 1 to 6 carbon atoms, R 2 is a substituent group represented by one of the following chemical formulas (4) to (6), and R 3 is a hydroxyl group, an alkoxy group having 1 to 6 carbon atoms, or an alkyl group having 1 to 6 carbon atoms, and

in chemical formula (6), R 6 is a hydrogen atom, an aminoalkyl group having 1 to 6 carbon atoms or an alkyl group having 1 to 6 carbon atoms, and IC is hydrogen atom or an aminoalkyl group having 1 to 6 carbon atoms;
contacting all or a part of the surface of the metal base material with an oxidizing agent selected from the group consisting of nitrous acid, sulfurous acid, persulfate, bromic acid, an iodine compound, chloric acid, HMnO 4 , HVO 3 , H 2 MoO 4 , H 2 WO 4 , hydrogen peroxide and salts thereof after the surface treatment step; and
electropainting the metal base material with a cathodic electrodeposition coating material consisting of an amine-modified epoxy resin, a curing agent, and a sealing agent.

12. A surface treatment method for improving uniformity of a cathodic electrodeposition coating film, the method comprising the steps of:
treating a surface of a metal base material to form a rust-resistant film by applying to the surface of the metal base material a treatment composition comprising at least one of zirconium ions or titanium ions; at least one stabilizing agent selected from the group consisting of an amino acid compound, an aminocarboxylic acid comp

Assignees

• Inbe Toshio
• Kameda Hiroshi
• Futsuhara Masanobu
• Akiyama Kazuto
• Chemetall Gmbh

Inventors

• Inbe Toshio
• Kameda Hiroshi
• Futsuhara Masanobu
• Akiyama Kazuto

Classifications

• C23C2222/20

  Use of solutions containing silanes · CPC title

• C08L79/02

  Polyamines · CPC title

• C25D13/02

  with inorganic material · CPC title

• C08G73/0246

  Polyamines containing other atoms than carbon, hydrogen, nitrogen or oxygen in the main chain · CPC title

• C25D13/22

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