CHEMICAL CONVERSION AGENT AND METAL SURFACE TREATMENT METHOD

• US 20160040298A1
• Filed: 04/03/2014
• Published: 02/11/2016
• Est. Priority Date: 04/03/2013
• Status: Active Grant

• Current Assignee: Nippon Paint Surf Chemicals Co., Ltd. (Rainbow Light Limited)
• Original Assignee: Nippon Paint Surf Chemicals Co., Ltd. (Rainbow Light Limited)
• Inventors: MIZUNO, Akihiro, MATSUI, Norizumi
• Granted Patent: US 10,138,559 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: C08K 2003/3045 Sulfates
• CPC Class Codes: C08K 3/28 Nitrogen-containing compounds
• CPC Class Codes: C08K 3/30 Sulfur-, selenium- or tellurium-containing compounds
• CPC Class Codes: C08K 5/04 Oxygen-containing compounds C08K5/0091 takes precedence
• CPC Class Codes: C08K 5/057 Metal alcoholates metal enolates C08K5/0091
• CPC Class Codes: C08K 5/098 Metal salts of carboxylic acids
• CPC Class Codes: C08L 29/04 Polyvinyl alcohol; Partially hydrolysed homopolymers or copolymers of esters of unsaturated alcohols with saturated carboxylic acids
• CPC Class Codes: C09D 5/08 Anti-corrosive paints
• CPC Class Codes: C09D 5/084 Inorganic compounds
• CPC Class Codes: C23C 22/40 containing molybdates, tungstates or vanadates
• CPC Class Codes: C23C 22/44 containing also fluorides or complex fluorides
• CPC Class Codes: C23C 22/82 After-treatment

Abstract

Provided is a chemical conversion agent that, with respect to an aluminum metal material, etc., contributes to superior corrosion and moisture resistance, contributes to superior adhesion with a laminate film, and contributes to superior hydrofluoric acid and alkali resistance. The chemical conversion agent includes: one or more type of metal element (A) selected from a group comprising of zirconium, titanium, and hafnium; vanadium element (B); and a resin (C). The resin (C) includes a polyvinyl alcohol resin (C1). The ratio (Wa/Wb) of the weight-based total content (Wa) of the metal element (A) relative to the weight-based content (Wb) of vanadium element (B) is 0.1-15, and the ratio ((Wa+Wb)/Wc1) of the weight-based total content (Wa+Wb) of the metal element (A) and the vanadium element (B) relative to the weight-based total content (Wc1) of the polyvinyl alcohol resin (C1) is 0.25-15.

Claims

1. A chemical conversion agent comprising one, or two or more metal element(s) (A) selected from the group consisting of zirconium, titanium, and hafnium,

a vanadium element (B), and

a resin (C),

wherein the resin (C) includes a polyvinyl alcohol-based resin (C1) consisting of at least one of polyvinyl alcohol and a derivative thereof,

the value of a ratio (Wa/Wb) of the mass-based total content (Wa) of the metal element (A) to the mass-based content (Wb) of the vanadium element (B) is 0.1-15, and

the value of a ratio ((Wa+Wb)/Wc1) of the mass-based total content (Wa+Wb) of the metal element (A) and the vanadium element (B) to the mass-based total content (Wc1) of the polyvinyl alcohol-based resin (C1) is 0.25-15.

2. The chemical conversion agent according to claim 1, wherein the resin (C) further includes one, or two or more metal ion-crosslinkable polymer(s) (C2), and

the value of a ratio (Wc2/(Wc1+Wc2)) of the mass-based total content (Wc2) of the metal ion-crosslinkable polymer (C2) to the mass-based total content (Wc1+Wc2) of the polyvinyl alcohol-based resin (C1) and the metal ion-crosslinkable polymer (C2) is 0.4 or less.

3. The chemical conversion agent according to claim 2, which includes, as the metal ion-crosslinkable polymer (C2), one, or two or more polymer(s) selected from the group consisting of polyacrylic acid, phosphoric acid polymer, phosphonic acid polymer, water-soluble or water-dispersible epoxy polymer, water-soluble or water-dispersible urethane-based polymer, and polyester.

4. The chemical conversion agent according to claim 1, wherein the concentration of the metal element (A) in the chemical conversion agent is 50-100,000 ppm by mass, and

the concentration of the vanadium element (B) is 50-100,000 ppm by mass, and

the total concentration of the resin (C) is 50-100,000 ppm by mass, and

a pH is 0.5-6.5.

5. The chemical conversion agent according to claim 1, wherein an average saponification degree of the polyvinyl alcohol-based resin (C1) is 80% or more.

6. The chemical conversion agent according to claim 1, which further includes a surfactant.

7. The chemical conversion agent according to claim 1, which is used for a surface treatment of an aluminum-based metal material.

8. A metal surface treatment method for treating a surface of a metal material, which comprises the steps of:

applying the chemical conversion agent according to claim 1 on the metal material, and

drying the chemical conversion agent applied on the metal material.