Abstract: A chromium-free aqueous liquid surface treatment agent that can impart both a good corrosion resistance and a good paint adherence to zinciferous-plated steel sheet contains as its essential components polyhydroxyaryl carboxylic acid and/or depside thereof and silane coupling agent with the formula (YR).sub.m R.sub.n SiX.sub.(4-m-n), in which R denotes alkyl groups; X is the methoxy or ethoxy group; Y is the vinyl, amino, mercapto, glycidoxy, or methacryloxy group; m=1 to 3; and n=0 to (3-m). The total content of said essential components is preferably 1 to 50 weight %.
Abstract: An aqueous liquid chromate free primary composition for forming a protective coating on metals, particularly aluminum, is made by reacting cobalt(II) cations, carboxylate anions, at least one other type of coordinate complexing agent for cobalt(III) cations, and an oxidizing agent in an aqueous solution in which the molar ratio of carboxylate anions to cobalt(II) cations is from 0.10 to 6.8 and the aqueous solution contains no more than 1% of each of ammonia, ammonium ions, and nitrite ions. The primary layer formed by this or any other composition that forms a coating containing metal atoms and oxygen atoms on a metal substrate is advantageously sealed by further treatment with an aqueous solution of sodium ammonium decavanadate, optionally after an intermediate step of immersing in water for a few minutes between the primary treatment and the sealing treatment.
Abstract: A high quality lubricant for heavy duty service air conditioner and refrigerator compressors, especially those using chlorine free hydrofluorocarbon refrigerant working fluids, is provided by mixed esters of hindered polyols, most desirably di-pentaerythritol, usually mixed with some pentaerythritol, with a mixture of carboxylic acids including at least some of each of iso-pentanoic acid and iso-nonanoic acid.
Abstract: An aqueous liquid composition containing dihydrogen phosphate salt, surfactant(s), and a dual coordinate bonding agent for iron cleans soiled metal surfaces without damaging any plastic parts that come into contact with the composition, supporting the growth of bacteria that cause unpleasant odors, or obscuring the transparency of any transparent window that it contacts. The composition is particularly useful for cleaning unpainted aluminum sided rail transport cars that have polycarbonate housings insulating electrical contact points that provide motive electric power to the cars; many conventional aqueous alkaline and acid cleaners promote stress cracking of polycarbonate plastics.
Abstract: From not more than three blending stocks, it is possible to prepare a wide variety of mixtures of esters of hindered polyhydric alcohols that are especially valuable lubricants for chlorine-free fluorocarbon refrigerant heat transfer fluids, particularly Refrigerant 134a (1,1,1,2-tetrafluoroethane).
Abstract: An aqueous liquid composition containing acid fluoride ions (i.e., HF.sub.2.sup.-) not derived from hydrogen fluoride, together with an acid stronger than acid fluoride ions, and, preferably, surfactant, is very effective in brightening unpainted metal surfaces such as those of stainless steel and aluminum without reducing the transparency of any glass objects such as windows with which the composition may come into contact. Otherwise similar compositions containing aqueous hydrofluoric acid usually etch glass in such a way as to reduce its transparency. The invention is particularly useful for brightening soiled or otherwise darkened surfaces of rail passenger cars.
Abstract: A concentrated aqueous solution containing:(A) a component of dissolved phosphate ions;(B) a component of dissolved hexavalent chromium;(C) a component of dissolved anions selected from the group consisting of BF.sub.4.sup.-, AlF.sub.6.sup.-3, SiF.sub.6.sup.-2, TiF.sub.6.sup.-2, FeF.sub.6.sup.-3, SnF.sub.6.sup.-2, ZrF.sub.6.sup.-2, and HfF.sub.6.sup.
Abstract: An improved aqueous liquid composition for power washing of paint masks contains: organic film-forming polymer, preferably polyacrylamide; inorganic salts, preferably a combination of alkali metal pyrophosphate, metaborate, and tetraborate; and dissolved organic molecules that (i) are hydrocarbons except for having hydroxyl substituents and, optionally, having one or more other types of substituents selected from halogen atoms, keto groups, and aldehydo groups and (ii) have a number ratio of oxygen atoms to carbon atoms that is at least 0.5; and, optionally but preferably, free boric acid.
Abstract: To improve the water resisting secondary adhesion of paint films to zinc phosphate conversion coatings on aluminum, the initially formed conversion coating is treated by spraying with a second liquid treatment composition that either is itself a liquid composition capable of forming a zinc phosphate conver- sion coating on aluminum or is made by diluting such a conversion coating forming composition.
Abstract: A reaction rinse containing strong alkali, betaine surfactants, and a complexing agent for iron enhances the gloss of a dried and cured autodeposited coating that is contacted with the reaction rinse while still wet, particularly if the autodeposited coating consists predominantly of a copolymer of vinylidene chloride.
November 12, 1996
Date of Patent:
July 28, 1998
Bashir M. Ahmed, Douglas A. Brown, William E. Fristad
Abstract: Heating an aqueous mixture of a fluoroacid such as H.sub.2 TiF.sub.6 and an oxide, hydroxide, and/or carbonate such as silica produces a clear mixture with long term stability against settling of any solid phase, even when the oxide, hydroxide, or carbonate phase before heating was a dispersed solid with sufficiently large particles to scatter light and make the mixture before heating cloudy. The clear mixture produced by heating can be mixed with soluble hexavalent and/or trivalent chromium, and preferably also nitrate and chloride ions to produce a composition that provides a conversion coating with good protection against corrosion while requiring substantially less chromium than previous coatings of equal corrosion protective quality.
Abstract: A water-borne autodepositing coating composition that has a pH of 1.6 to 5 and contains as essential components a water-dispersible or water-soluble organic coating-forming resin, a liquid dispersion of carbon black, acid, and oxidizing agent, and that may contain metal ions as an optional component, has an excellent storage stability and produces a strongly adherent and highly corrosion-resistant coating when the liquid dispersion of carbon black is an aqueous dispersion in which carbon black is dispersed using as a dispersant a naphthalenesulfonate-formaldehyde condensate.
Abstract: A highly corrosion-resistant, paint-adherent, and lubricating polymer-containing coating on a metal surface can be formed by contact with an aqueous solution (pH=2.0 to 6.5) that contains an acidic compound and polymer with the following formula (I): ##STR1## in which the X bonded to the phenyl ring in formula (I) represents a hydrogen atom, a hydroxyl group, a C.sub.1 to C.sub.5 alkyl group, a C.sub.1 to C.sub.5 hydroxyalkyl group, a C.sub.6 to C.sub.12 aryl group, a benzil group, a benzal group, an unsaturated hydrocarbon moiety condensed to the phenyl ring so as to form a naphthalene ring, or a group corresponding to formula (II): ##STR2## in which R.sup.1 and R.sup.2 in formula (II) each independently represent a hydrogen atom, a hydroxyl group, a C.sub.1 to C.sub.10 alkyl group, or a C.sub.1 to C.sub.10 hydroxyalkyl group; the Y.sup.1 and Y.sup.
Abstract: A surface of aluminiferous metal is brought into contact at 30.degree. C. to 65.degree. C. for 5 to 60 seconds with a surface treatment bath with a pH of 2.0 to 6.5 that contains phosphate ion, condensed phosphate ion, and a water soluble polymer in the following weight proportions: 1-30: 0.1-10: 0.2-20. This is followed by a water rinse and drying by heating. The water soluble polymer has a chemical structure conforming with formula (I): ##STR1## in which (i) each of X.sup.1 and X.sup.2 represents a hydrogen atom, a C.sub.1 to C.sub.5 alkyl group, or a C.sub.1 to C.sub.5 hydroxyalkyl group; (ii) each of Y.sup.1 and Y.sup.2 represents a hydrogen atom or a moiety "Z" that conforms to formula (II) or (III): ##STR2## wherein each of R.sup.1, R.sup.2, R.sup.3, R.sup.4, and R.sup.5 represents a C.sub.1 to C.sub.10 alkyl group or a C.sub.1 to C.sub.10 hydroxyalkyl group; (iii) the average value for the number of Z moieties substituted on each phenyl ring in the polymer molecule is from 0.2 to 1.
Abstract: An aqueous solution of manganese phosphate and phosphoric acid, preferably with little or no content of any material conventionally recognized as an accelerator or of any divalent metal ions other than manganese and iron, forms a good quality paint undercoating phosphate conversion coating on metal substrates, particularly on steel and galvanized steel substrates, when contacted by spraying or immersion with the substrates at a temperature of 54.degree.-65.degree. C. for a time of 0.5-5 minutes.
November 12, 1996
Date of Patent:
March 17, 1998
Mervet S. Boulos, David C. Montrose, Michael Petschel
Abstract: A chromium and ferricyanide free aqueous deoxidizer/desmutter for aluminum and magnesium alloys contains nitric acid, ferric ions, and molybdate and/or condensed molybdate anions and preferably also sulfate and fluoride.
Abstract: The rapid, low-temperature formation of a bright blue surface on hot-dip zinc/aluminum alloy-plated steel sheet that contains 0.1 to 60 weight % aluminum in the alloy, or on other surfaces of similar chemical composition, using conventional surface-treatment equipment, is achieved by treating the surface with a treatment bath that has a pH of 3.5 to 6.0 and that contains molybdenum compound at 0.2 to 3.0 weight % as molybdenum and simple or complex fluoride at 0.1 to 2.0 weight % as fluorine.
Abstract: Disclosed is an improved method for coating a zinc surface comprising treating said surface with an aqueous, acidic solution containing:(a) about 0.5 to about 4 percent phosphate ion;(b) an ion selected from the group consisting of zinc ions, manganese ions, and mixtures thereof, said ions being present at a level sufficient to form dihydrogen phosphate with substantially all of said phosphate ions; and(c) about 0.01 to about 1 percent complex fluoride ions; wherein the weight:weight ratio of complex fluoride ions:chloride ions in said solution is at a value of about 8:1 or greater.It is preferred that the ratio complex of fluoride ion to chloride ion (F.sup.- :Cl.sup.-) in said solution to be maintained at a value of greater than about 8:1, preferably greater than about 10:1, and more preferably greater than about 14:1.