Chromium-free chemical treatment liquid and method of manufacturing member with chromium-free chemical coating
A chromium-free chemical conversion treatment liquid, formulated with specific ratios of aluminum, vanadium, and phosphoric acid, along with organic acids and silica sol, addresses the challenge of achieving high corrosion resistance on complex metal surfaces, providing an environmentally friendly solution.
JP2025088907APending Publication Date: 2025-06-12YUKEN KOGYO
4 Cites 0 Cited by
Patent Information
- Application Number
- JP2023203725
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2023-12-01
- Publication Date
- 2025-06-12
AI Technical Summary
Technical Problem
Existing chromium-free chemical conversion treatment liquids lack sufficient corrosion resistance, especially when applied to complex-shaped metal surfaces.
Method used
A chromium-free chemical conversion treatment liquid containing an aluminum-containing substance, a vanadium-containing substance, and a phosphoric acid-containing substance, with specific molar concentration ratios and pH levels, along with the incorporation of a first organic acid and silica sol, to enhance corrosion resistance.
Benefits of technology
The proposed treatment liquid achieves a chemical conversion film with excellent corrosion resistance, even on complex-shaped metal surfaces, while being environmentally friendly and free of chromium.
✦ Generated by Eureka AI based on patent content.
Abstract
To provide a chromium-free chemical treatment liquid capable of forming a chromium-free chemical coating which is superior in corrosion resistance and takes environmental conservation into consideration.SOLUTION: There is provided a chromium-free chemical treatment liquid that contains aluminum-containing substance, vanadium-containing substance and phosphoric acid-containing substance, and has a first ratio of 0.1 to 2.0 as the ratio of the aluminum equivalent mol concentration of the aluminum-containing substance to the vanadium equivalent mol concentration of the vanadium-containing substance and a second ratio of 0.01 to 0.25 as the ratio of the phosphorus equivalent mol concentration of the phosphoric acid-containing substance to the aluminum equivalent mol concentration of the aluminum-containing substance, the pH being 1.0 to 4.0.SELECTED DRAWING: None
Need to check novelty before this filing date? Find Prior Art