Gel containing phosphate salts for passivation

• US 7,473,308 B2
• Filed: 09/20/2007
• Issued: 01/06/2009
• Est. Priority Date: 09/21/2006
• Status: Active Grant

• Current Assignee: Chunwoo Tech Company Limited
• Original Assignee: Chunwoo Tech Company Limited
• Inventors: Kim, Sang Jin, Park, Seong Shik
• Primary Examiner(s): Eashoo; Mark
• Assistant Examiner(s): ASDJODI, MOHAMMADREZA
• Application Number:
  US11/858,285
• Publication Number:
  US 20080207477A1
• Time in Patent Office: 474 Days
• Field of Search: 510/254, 428/423.1, 428/469, 528/75, 148/243, 148/253, 148/254, 148/259, 106/14.12, 106/14.41, 106/14.44
• US Class Current: 106/14.12
• CPC Class Codes: C08L 5/00 Compositions of polysaccharides or of their derivatives not provided for in groups C08L1/00 or C08L3/00
• CPC Class Codes: C09D 5/12 Wash primers
• CPC Class Codes: C09D 7/43 Thickening agents
• CPC Class Codes: C11D 1/66 Non-ionic compounds C11D1/002, C11D1/004, C11D1/008 take precedence
• CPC Class Codes: C11D 2111/20 Industrial or commercial equipment, e.g. reactors, tubes or engines
• CPC Class Codes: C11D 3/02 Inorganic compounds ; Elemental compounds
• CPC Class Codes: C11D 3/042 Acids
• CPC Class Codes: C11D 3/046 Salts
• CPC Class Codes: C11D 3/06 Phosphates, including polyphosphates
• CPC Class Codes: C11D 3/2086 Hydroxy carboxylic acids-salts thereof
• CPC Class Codes: C23C 22/42 containing also phosphates
• CPC Class Codes: C23G 1/02 with acid solutions

Abstract

Disclosed herein is a phosphate gel for passivation, which is used for the acid washing and phosphate coating of a corroded metal surface. The phosphate gel contains phosphate and gum.

Claims

1. A phosphate gel for passivation, which is used for the acid washing and phosphate coating of a corroded metal material, in which the phosphate gel is prepared by heating and cooling an aqueous phosphate solution, containing 30-70 wt % of phosphoric acid, 0.5-10 wt % of zinc powder, 0.5-5 wt % of calcium phosphate, 0.5-5 wt % of sodium molybdate, 0.5-10 wt % of gluconic acid, 0.1-1 wt % of a non-ionic surfactant, 1-4 wt % of gum and 12.8-66.9 wt % of water.

2. The phosphate gel of claim 1, wherein the gum is selected from the group consisting of gellan gum, Arabic gum, tamarind gum and carrageenan.