Metal treatment – Process of modifying or maintaining internal physical... – Processes of coating utilizing a reactive composition which...
Patent
1998-04-13
2000-11-28
Willis, Prince
Metal treatment
Process of modifying or maintaining internal physical...
Processes of coating utilizing a reactive composition which...
148260, 148275, 4273884, C23C 2207
Patent
active
061530220
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The present invention relates to a novel composition and method for the surface treatment of aluminum and its alloys, such as aluminum-manganese alloys, aluminum-magnesium alloys, and aluminum-silicon alloys, that contain at least 45% by weight of aluminum, all of these being jointly hereinafter briefly designated as "aluminiferous metals", in which the surface of an aluminiferous metal is provided with better corrosion resistance and adhesion to paint or synthetic resin film before said surface is painted or is laminated to a synthetic resin film. One field in which the present invention may be particularly effectively applied is the surface treatment of aluminiferous coils.
BACKGROUND ART
Chromate treatments are presently being used for the most part in the industrial surface treatment of aluminum coils. Typical examples of chromate treatments include chromic acid chromate conversion treatments and phosphoric acid chromate conversion treatments. Chromic acid chromate conversion treatment solutions were put to practical use around 1950 and are still widely used for fin members and the like in heat exchangers. This chemical conversion treatment solution consists primarily of chromic acid (CrO.sub.3) and hydrofluoric acid (HF), with a promoter added, and forms a film containing some hexavalent chromium. Phosphoric acid chromate conversion treatment solutions are based on the invention in U.S. Pat. No. 2,438,877 from 1945. This chemical conversion treatment solution contains chromic acid (CrO.sub.3), phosphoric acid (H.sub.3 PO.sub.4), and hydrofluoric acid (HF). The film that is formed consists primarily of hydrated chromium phosphate (CrPO.sub.4.4H.sub.2 O). Since the film does not contain hexavalent chromium, it is widely used at present for the paint undercoating treatment of beverage can bodies, particularly drawn and ironed aluminum cans and lids. However, in the interests of environmental protection, a need has arisen for surface treatment solutions which contain no chromium. In recent years, the painting or lamination following such surface treatment has been followed by an increasingly wide range of shaping processes, with the need for increasingly stringent levels of processing, but films made from inorganic systems such as chromate suffer from problems; e.g., the film is broken when bent sharply, preventing adequate performance from being realized, and the like. There is thus strong demand for the development of a technique for forming a flexible film with better corrosion resistance and/or adhesion in articles of manufacture that are shaped after the conversion coating is formed.
Treatment solutions or methods intended to provide the surface of aluminiferous metals with corrosion resistance and paint adhesion using a water-soluble resin have been proposed in Japanese Laid-Open Patent Applications 61-91369, 1-172406, 1-177379, 1-177380, 2-608, 2-609, and others. In these conventional treatment methods, the metal surface is treated with a solution containing a derivative of a polyhydric phenol compound. Problems in these conventional methods, however, are that it is difficult to form a sufficiently stable film in a short period of time on the surface of aluminiferous metal materials, and adequate corrosion resistance cannot be obtained.
DISCLOSURE OF THE INVENTION
Problems to Be Solved by the Invention
The present invention is intended to remedy the aforementioned drawbacks of the conventional technology, and more specifically is intended to offer a novel composition and method for surface treating aluminiferous metals, which allow the surface of an aluminiferous metal to be provided in a short period of time with better corrosion resistance and paint or laminated film adhesion, without the use of chromium, and which also allow a film with better workability to be formed.
SUMMARY OF THE INVENTION
It has been found that an aqueous liquid surface treatment composition containing phosphoric acid ions, condensed phosphoric acid ions, an oxidizer, and a water-soluble polymer
REFERENCES:
patent: 2438877 (1948-03-01), Spruance, Jr.
patent: 4714752 (1987-12-01), Sokalski
patent: 4963596 (1990-10-01), Lindert et al.
patent: 4970264 (1990-11-01), Lindert et al.
patent: 5039770 (1991-08-01), Lindert et al.
patent: 5063089 (1991-11-01), Lindert et al.
patent: 5068299 (1991-11-01), Lindert et al.
patent: 5116912 (1992-05-01), Lindert et al.
patent: 5246507 (1993-09-01), Kodama et al.
patent: 5266410 (1993-11-01), Lindert et al.
patent: 5356491 (1994-10-01), Aoki et al.
patent: 5427632 (1995-06-01), Dolan
patent: 5728234 (1998-03-01), Aoki et al.
patent: 5733386 (1998-03-01), Yoshida
Ehara Ryoji
Yoshida Masayuki
Harper Stephen D.
Harper Wayne C.
Henkel Corporation
Oltmans Andrew L.
Willis Prince
LandOfFree
Composition and process for surface treatment of aluminum and it does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Composition and process for surface treatment of aluminum and it, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Composition and process for surface treatment of aluminum and it will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1720765