Bulk Chemicals, Inc.

Betz Laboratories, Inc.

Jose B Rivera

Ted M Schlosser

Michael D Wert

Lawrence E Jones

William L Harpel

Philip D Deck

Richard J Church

Charles R Ike

Robert L McMaster

Anthony P Petrole

Cody Hanna

Aqueous compositions useful as pretreatments prior to painting and to reduce the formation of rust in the uncoated condition consist essentially of water, an organo-functional silane, a compound of a Group IV-B element, and optionally a polyvinyl alcohol, stabilizing agents, wetting agents, thickeners, and biocides, and have an alkaline pH&#x3e;7. A process for treating a metal surface includes contacting the surface with such an aqueous composition. The compositions and processes were found to have further benefits in comparison to the zinc phosphate metal pretreatment thought to be the standard in the industry. Preferably, the pH of the compositions is alkaline, which has been found to improve the efficacy of a silane as a surface treatment to improve uniformity of paint adhesion. By operating in the alkaline pH range, it was found that flash rusting and/or blush rust were significantly reduced.

Process and seal coat for improving paint adhesion

A method of preparing an aqueous composition of a chromium III compound, comprising adding hydrogen peroxide to a mixture comprising water and a chromium VI compound in the presence of at least one acid according to the formula HGF, in which G is a Group IV-B element. The composition may contain less than 500 ppm of alkali metal ions and less than 200 ppm of halide ions, relative to chromium and may test negative for chromium VI using s-diphenylcarbazide. The composition may be used for treating a metal surface, among other applications.

Method for making and using chromium III salts

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.

Method for treating magnesium die castings

An aqueous solution and method for applying the solution to a metal surface form a zinc phosphate coating on the metal surface. The zinc phosphate coating minimizes corrosion and improves adhesion of subsequently coated materials such as sealants and paints. The solution of the composition and method of application consume free acidity otherwise left on the metal surface, and obviate the need for subsequent rinsing or extensive drying or stoving operations. The composition includes an aqueous solution including water, zinc dihydrogen phosphate, phosphoric acid, a polyhydric polymer, a metal salt, and optionally, a fluoride.

No rinse zinc phosphate treatment for prepaint application

A method and composition for treating metal surfaces to improve corrosion resistance and paint adhesion. The composition is a non-corrosive aqueous solution including water, a polymeric compound, an additive, and dispersed silica. In a preferred embodiment, the polymeric compound may be a polymer having a plurality of carboxylic functional groups and a plurality of hydroxyl groups. The polymeric compound may be a bifunctional copolymer or the reaction product of a first polymer having a plurality of carboxylic functional groups (e.g., polyacrylic acid or polymethylvinylmaleic anhydride), and a second polymer having a plurality of hydroxyl groups (e.g., polyvinyl alcohol). The additive is selected from at least one of: (i) an acid of a group IV-B element and a weak base, and (ii) an ammonium salt of a group IV-B compound such as ammonium zirconium carbonate. An exemplary acid of a group IV-B element is fluotitanic acid and an exemplary weak base is ammonium hydroxide. Dispersed silica is added, and any attack of the silica is minimized. The method for improving corrosion resistance and paint adhesion of a metal surface includes contacting the metal surface with a composition as described above and drying the composition in place. Prior to contacting the metal surface with such a composition, the metal surface may be cleaned and rinsed.

Method and composition for treating metal surfaces including dispersed

A method and composition for coating a metal for use in connection with improving corrosion resistance and paint adhesion. The composition is a non-corrosive ester cross-linked polymer system having a plurality of carboxylic functional groups and a plurality of hydroxyl groups. The polymer system may be a bifunctional copolymer or the reaction product of a first polymer having a plurality of carboxylic functional groups (e.g. polyacrylic acid or polymethylvinylmaleic anhydride), and a second polymer having a plurality of hydroxyl groups (e.g. polyvinyl alcohol). The resulting reaction product of these two polymers is a cross-linked polymeric blend. A compound of a Group IV-B element may be added to this polymer blend to increase the degree of cross-linking and improve paint adhesion and corrosion resistance. Such a Group IV-B compound may be an acid such as fluozirconic acid, fluotitanic acid or fluohafnic acid, or a salt such as ammonium zirconium carbonate. If high concentrations are required, the pH of the solution may be increased to prevent gelation and promote prolonged stability. The method for improving corrosion resistance and paint adhesion of a metal surface includes contacting the metal surface with a composition of the present invention and drying the composition in place. Prior to contacting the metal surface with such a composition, the metal surface may be cleaned and rinsed.

Method and composition for treating metal surfaces

A method and composition for coating a metal for use in connection with improving corrosion resistance and paint adhesion. The composition is a non-corrosive ester cross-linked polymer system having a plurality of carboxylic functional groups and a plurality of hydroxyl groups. The polymer system may be a bifunctional copolymer or the reaction product of a first polymer having a plurality of carboxylic functional groups (e.g. polyacrylic acid or polymethylvinylmaleic anhydride), and a second polymer having a plurality of hydroxyl groups (e.g. polyvinyl alcohol). The resulting reaction product of these two polymers is a cross-linked polymeric blend. A compound of a Group IV-B element may be added to this polymer blend to increase the degree of cross-linking and improve paint adhesion and corrosion resistance. Such a Group IV-B compound may be an acid such as fluozirconic acid, fluotitanic acid or fluchafnic acid, or a salt such as ammonium zirconium carbonate. The method for improving corrosion resistance and paint adhesion of a metal surface includes contacting the metal surface with a composition of the present invention and drying the composition in place. Prior to contacting the metal surface with such a composition, the metal surface may be cleaned and rinsed.

A method for treating a metal surface involves contacting the metal surface with an aqueous silicate solution, contacting the silicate-coated metal surface with an aqueous organo-functional silane solution, and then contacting the silane-coated metal surface with a chrome-free pretreatment. Preferably, the bath containing the aqueous silicate solution also includes a cleaning agent for cleaning the metal surface. Alternatively, the metal surface may be cleaned in a separate step before the metal surface is contacted with the aqueous silicate solution and, optionally, the metal surface is rinsed with water after the metal surface is cleaned and before the metal surface is contacted with the aqueous silicate solution. The silicate-coated metal surface may be rinsed with water before it is contacted with an aqueous organo-functional silane solution. In addition, the silane-coated metal surface may be rinsed with water before it is contacted with a chrome-free pretreatment. As an alternative or in addition to these rinsing steps, excess solution may be removed from the silicate-coated or silane-coated metal surface prior to the subsequent steps. Preferably, the aqueous silicate solution includes water and either sodium silicate or potassium silicate, and the aqueous organo-functional silane solution comprises an aminopropyl silane and water.

Method for treating metal surfaces using a silicate solution and a

A method and composition for indicating the presence of a chrome-free pretreatment for improving the paint adhesion and corrosion resistance of a metal surface. The presence of the pretreatment is indicated by adding a compound to the chrome-free pretreatment which causes the pretreatment to fluoresce under an ultraviolet light. The additive which causes the pretreatment to fluoresce under an ultraviolet light is an ultraviolet tracer, such as a stilbene or a coumarin derivative, and the method according to this invention includes exposing the coated metal to ultraviolet light.

Method and composition for indicating the presence of chrome-free

A cleaning and etching solution and method for metal surface is disclosed which is an alkaline formulation which includes a surfactant combination of a low foaming ethylene oxide - propylene oxide block copolymer surfactant and a defoaming reverse ethylene oxide - propylene oxide block copolymer. The preferred cleaner includes an alkali metal hydroxide, an alkali metal salt of gluconic acid and preferably an alkali tripolyphosphate and the surfactant combination.

Growing community of inventors

Philadelphia, PA, United States of America

Jose B Rivera