Abstract: A copper foil for printed circuits having a rust-preventive and heat-discoloration resistant coat, comprising a first layer of zinc or an alloy or a compound or a composition including zinc mainly, and a second layer including a silane coupling agent and phosphorus or a phosphorus compound, said second layer being positioned on the first layer. A method of producing a copper foil for printed circuits comprising the steps of treating the shiny side of a copper foil in a manner of cathode electrolysis in an alkaline solution including zinc ions and chrome ions, or providing the shiny side of a copper foil with a thin plating layer of zinc or a zinc alloy, and thereafter applying onto the treated surface of the copper foil a solution including a silane coupling agent and phosphorus or a phosphorus compound.
Abstract: Substantially improved retention of hydrophilicity after exposure to high temperature can be provided on a metal substrate, particularly an aluminum alloy of the type used for heat exchanger fins by an aqueous liquid hydrophilicizing treatment composition containing acrylic and/or methacrylic acid polymer or copolymer, polyether alcohol, and alkali metal silicate. The treatment composition may also contain an anti-microbial agent and additional alkalinizer. The hydrophilicizing treatment is preferably applied over a conventional conversion coating, particularly a chromium phosphate or chromium oxide conversion coating.
Abstract: A chromium free conversion coating at least equivalent in corrosion protective quality to conventional chromate conversion coatings can be formed on metals, particularly galvanized steel, by a dry-in-place aqueous acidic liquid comprising:(A) a component of anions, each of said anions consisting of (i) at least four fluorine atoms and (ii) at least one atom of an element selected from the group consisting of titanium, zirconium, hafnium, silicon, and boron and, optionally, (iii) one or more oxygen atoms;(B) a component of cations of elements selected from the group consisting of cobalt, magnesium, manganese, zinc, nickel, tin, zirconium, iron, aluminum and copper; the ratio of the total number of cations of this component to the total number of anions of component (A) being at least 2:5; and(C) sufficient free acid to give the composition, after dilution with from 1 to 19 times its own weight of water, a pH in the range from 0.5 to 5.
Abstract: A magnetically anisotropic magnet substrate is coated with at least one layer of nickel plating followed by a chromate layer. The chromate top layer improves the corrosion resistance of the coated magnet substrate. In a preferred embodiment, the layer of nickel plating includes a first layer of a non-bright nickel plating followed by a second layer of a semi-bright nickel plating. One embodiment adds a copper under-layer below the nickel plating.
Abstract: Corrosion resistant coatings are formed on aluminum by immersion in aqueous olutions containing chromic salts, a fluoride ion from compounds such as a fluosilicate with an alkali added near or slightly beyond the precipitation of the insoluble basic compounds. Trivalent chromium films formed on the aluminum surface when tested in 5% NaCl salt spray chamber showed corrosion resistance in excess of 96 hours. After a post-treatment with peroxide or permanganate solutions, the corrosion resistance for the aluminum substrates exceeded 168 hours. Trivalent chromium coated aluminum serves as an effective base for paint primers. Anodized aluminums were also afforded excellent corrosion resistance, after being treated in dilute/basic chromic sulfate solutions and post-treated with peroxide.
Type:
Grant
Filed:
September 27, 1993
Date of Patent:
April 19, 1994
Assignee:
The United States of America as represented by the Secretary of the Navy
Abstract: Seal coating compositions and method of applying same, to metallic surfaces, particularly aluminum or alloys thereof, containing a previously formed protective coating on the metal surface, to provide for improved corrosion resistance beyond that provided by the previously formed protective coating. Aqueous solutions of the seal coating components are applied to the metal surface containing the previously formed coating which is subsequently rinsed and dried to provide metal articles having improved resistance to corrosion.
Type:
Grant
Filed:
April 15, 1991
Date of Patent:
July 13, 1993
Assignee:
Henkel Corporation
Inventors:
Lawrence R. Carlson, Philip M. Johnson, John R. Pierce
Abstract: A process for forming improved chromate conversion coatings on zinc surfaces by treating the zinc surface with an aqueous acidic chromating solution which contains hexavalent chromium and a soluble inorganic salt which has an cation which will form an insoluble organic silicate and, thereafter, treating the thus-formed chromate conversion coating with an aqueous alkaline silicate solution which contains a soluble alkali metal silicate and fluoride ions.
Abstract: Hydrophilic coatings on aluminum plates comprising, on a solid basis, 5-25 parts by weight of a sodium salt and/or a potassium salt of carboxymethylcellulose, and 25-50 parts by weight of an ammonium salt of carboxymethylcellulose, and 25-70 parts by weight of N-methylol acrylamide, which may further contain 1.5-15 parts by weight of polyacrylic acid and 0.6-9 parts by weight (as Zr) of a zirconium compound, per 100 parts by weight of the above indispensable components.
Abstract: A method of producing highly corrosion-resistant surface-treated steel plates where Cr elusion is small in spite of drying at low temperatures and corrosion resistance is excellent. In a process for producing surface treated steels where Zn type plated steels are treated through (i) chromate treatment, (ii) coating a resin composition and (iii) baking treatment, zirconium fluoride ion and Zn ion of appropriate amounts are added into the chromate bath, and Cr.sup.6+ /Cr.sup.3+ ratio in the bath is controlled to be low. Further the resin composition to be coated after the chromate treatment is rendered a solvent type resin composition obtained by adding silica and/or sparingly water soluble Cr compound to basic epoxy resin.
Abstract: An aqueous solution of a reducing agent is applied to a chromate coated metal surface to reduce the extent to which the chromate coating undergoes dissolution during a subsequent cleaning process.
Abstract: An aqueous surface treatment composition for forming a hydrophilic coating comprising: (a) alkali metal silicate, (b) aminoalcohol, and (c) a water-soluble resin selected from the group consisting of a water-soluble nylon, a natural polysaccharide and a water-soluble, natural protein, and/or a water-soluble silane coupling agent. This aqueous surface treatment composition is used to form a hydrophilic coating on an aluminum surface having a corrosion-resistant coating layer. The hydrophilic coating prepared from this compositon has good hydrophilic nature and corrosion resistance with substantially no unacceptable odor.