Coating processes – With pretreatment of the base – Etching – swelling – or dissolving out part of the base
Patent
1999-02-03
2000-10-03
Beck, Shrive
Coating processes
With pretreatment of the base
Etching, swelling, or dissolving out part of the base
427327, 4274301, B05D 300
Patent
active
061269972
ABSTRACT:
A method for treating magnesium die castings sufficiently cleans the die castings and improves their paint adhesion and corrosion resistance by utilizing hydroxy acetic acid, among other constituents. The method includes cleaning the castings with an alkaline cleaning solution, rinsing with water, pickling the castings with an aqueous hydroxy acetic acid solution, rinsing with water again, and then contacting the castings with a chrome-free pretreatment. The alkaline cleaning and pickling steps appear to remove substantially all die casting impurities in order to adequately prepare the metal for application of the pretreatment. The chrome-free pretreatment may be an organofunctional silane solution or an aqueous polymeric system having hydroxyl and carboxylic functional groups along with a compound of a group IV-B element. The pretreatment is then painted or contacted with another decorative coating, with no rinsing step occurring between the pretreatment and painting steps. The treatment process attains good paint adhesion and corrosion resistance of the castings while utilizing environmentally friendly constituents.
REFERENCES:
patent: 2302939 (1942-11-01), De Long
patent: 2335826 (1943-11-01), George
patent: 3061467 (1962-10-01), Vincent
patent: 3378410 (1968-04-01), Barlett
patent: 4370173 (1983-01-01), Dollman
patent: 4780153 (1988-10-01), Gudhe et al.
patent: 5043022 (1991-08-01), Kosters et al.
patent: 5244738 (1993-09-01), Seibel
patent: 5393353 (1995-02-01), Bishop
patent: 5451431 (1995-09-01), Purnell et al.
patent: 5578347 (1996-11-01), Chan
patent: 5634986 (1997-06-01), Beck
patent: 5645650 (1997-07-01), Ishizaki et al.
patent: 5700523 (1997-12-01), Petrole et al.
patent: 5859106 (1999-01-01), Jones et al.
Technical Note #20--Surface Treatments. (No date).
Murray, R.W. and Hillis, J.E., "Magnesium Finishing: Chemical Treatment and Coating Practices," SAE Technical Paper Series, International Congress and Exposition, Detroit, Michigan, Feb. 26-Mar. 2, 1990.
Hawke, D. and Gaw, K., "Effects of Chemical Surface Treatments on the Performance of an Automotive Paint System on Die Cast Magnesium," SAE Technical Paper Series, International Congress & Exposition, Detroit, Michigan, Feb. 24-28, 1992.
Skar, J.I., Manfred, W., Albright, D., "Non-Chromate Conversion Coatings for Magnesium Die Castings," SAE Technical Paper Series, International Congress & Exposition, Detroit, Michigan, Feb. 24-27, 1997 (Reprinted from: Characteristics and, Applications of Magnesium in Automotive Design (SP-1250).
Chromating of magnesium castings--Process: NH 35 (Norsk Hydro, Magnesium Division). (No date).
Hawke, D., and Albright D.L., "A Phosphate-Permanganate Conversion Coating for Magnesium" (Hydro Magnesium Marketing--Reprinted by permission of the publisher from "A Phosphate-Permanganate Conversion Coating for Magnesium," David Hawke and D. L. Albright, Metal Finishing, Oct. 1995, pp. 34-38. Copyright 1995 by Elsevier Science.
Ford Laboratory Test Methods, Salt Spray Resistance Test for Paiunted Panels and Parts, Product and Manufacturing Engineering Staff, May 11, 1990.
Ike Charles R.
McMaster Robert L.
Rivera Jose B.
Beck Shrive
Bulk Chemicals, Inc.
Calcagni Jennifer
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