US3154438A - Process for treating metal surfaces - Google Patents

Process for treating metal surfaces Download PDF

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Publication number
US3154438A
US3154438A US178247A US17824762A US3154438A US 3154438 A US3154438 A US 3154438A US 178247 A US178247 A US 178247A US 17824762 A US17824762 A US 17824762A US 3154438 A US3154438 A US 3154438A
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United States
Prior art keywords
phosphate
water soluble
metal
solution
aqueous
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Expired - Lifetime
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US178247A
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English (en)
Inventor
Keller Heinz
Kaysser Friedrich
Rausch Werner
Stenger Walter
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Occidental Chemical Corp
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Hooker Chemical Corp
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Assigned to HOOKER CHEMICALS & PLASTICS CORP, A CORP OF NY reassignment HOOKER CHEMICALS & PLASTICS CORP, A CORP OF NY ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: OXY METAL INDUSTRIES CORPORATION
Anticipated expiration legal-status Critical
Assigned to OCCIDENTAL CHEMICAL CORPORATION reassignment OCCIDENTAL CHEMICAL CORPORATION CHANGE OF NAME (SEE DOCUMENT FOR DETAILS). EFFECTIVE MARCH 30, 1982. Assignors: HOOKER CHEMICAS & PLASTICS CORP.
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    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C22/00—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
    • C23C22/82—After-treatment
    • C23C22/83—Chemical after-treatment
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05D3/00—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials
    • B05D3/10—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials by other chemical means
    • B05D3/102—Pretreatment of metallic substrates
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05D7/00—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials
    • B05D7/14—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials to metal, e.g. car bodies
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05D2401/00—Form of the coating product, e.g. solution, water dispersion, powders or the like
    • B05D2401/20—Aqueous dispersion or solution

Definitions

  • the present invention relates to an improved method for preparing metal surfaces to receive adherent films of water soluble base paint and a process of coating metal with smooth, adherent thermoset resin films, and more particularly relates to a method for rinsing a metal surface preliminarily treated in acidic solution to form thereon a protective integral chemical coating such as a phosphate, chromate, oxalate, or the like, and thereafter coating said surface with a water soluble thermosettable resin.
  • the coating is ordinarily dried prior to the application of the finish coating of lacquer, varnish or paint and at least in those high quantity production lines which fabricate automobile bodies, refrigerator shells, stoves and the like, the final coating is applied by spraying.
  • water soluble paint systems it has become feasible to eliminate the drying step and to apply a water soluble paint on the chemically prepared metallic surface immediately following the final rinse in the chemical treatment. It has been found that in such processes that difficulties are encountered during operation including the formation of irregularities or roughness in the final cured film or the precipitation of conglomerates or sludge within the tank or receptacle which houses the water soluble paint.
  • the final stepI in the chemical treatment of the metal surface preparatory to its contact with the water soluble paint comprises rinsing that surface in an aqueous solution having a pH in the range of about 7 to about ll, and preferably rinsing that surface in an aqueous solution of an amine.
  • Amines which have been found to be suitable for the purposes of this invention include ammonia, diethylamine, triethylamine, triethanolamine, morpholine, cyclohexylamine, dicyclohexylamine, aminopropanol, and
  • Such amine solutions may satisfactorily contain other anions, such as the phosphate anion, or amine phosphate esters of monoand di-phosphoric acids such as, for example, monomethyl amine phosphate, ethyl amine phosphate, isopropyl amine phosphate, monoethanol amine phosphate, diamyl amine phosphate, 2 amino-Z-methyl-l-propanol amine phosphate, cyclohexylamine phosphate, tertiary octyl amine phosphate, and ethylene diamine phosphate.
  • amine anion such as, for example, monomethyl amine phosphate, ethyl amine phosphate, isopropyl amine phosphate, monoethanol amine phosphate, diamyl amine phosphate, 2 amino-Z-methyl-l-propanol amine phosphate, cyclohexylamine phosphate, tertiary octyl amine
  • the rinse may also include small quantities of alcohol or other compatible solvent and a small quantity of a non-ionic, cationic or anionic wetting agent.
  • concentration of the amine which is best for use in any particular case is dependent upon its inherent alkalinity and solubility in water and the optimum quantity for use is an amount which will produce the pH in the range of about 7-10 and preferably in the range of 8-10.
  • aqueous acidic rinses which are of value for the purpose of enhancing corrosion resistance and the quality of the coating as a base for paint, such as for example, a dilute aqueous hexavalent chromium containing solution or a phosphoric acid containing solution or tthe like.
  • the entrapped acidic material which results from such a rinse is particularly damaging to the quality of the Water soluble paint when the freshly rinsed chemically coated surface is thereafter dipped or immersed in the water soluble paint tank and such a procedure results in a precipitation of the components of the water soluble paint in the application tank and an ultimate destruction of the quality of the water based paint film.
  • water soluble paint, lacquer or varnishes sprayed or atomized on such an acidic surface coating produces a rough, non-uniform film which is apparent after heat curing of the resin.
  • aqueous alkaline rinse of this invention it is undesirable to include in the aqueous alkaline rinse of this invention any material, inorganic or organic which after curing of the water soluble paint film remain in the film in a form which is soluble in Water since the leaching of such material from the final film reduces the corrosion resistance of the total film to humid conditions. For this reason it is advantageous to employ distilled water or water which has been deionized for the preparation of the rinse solutions to this invention.
  • All of the known types of water soluble resins have been found to be improved by the preliminary use of the rinse solutions of this invention including, for example, the water soluble phenolic resins, water soluble acrylic resins, water soluble melamine resins, water soluble alkyd phenolic resins, the water soluble alkyd melamine resins, the water soluble melamine modified acrylic resins, the water soluble fatty acid modified alkyd resins, etc.
  • fatty acid free phthalate resin available under the trade name Alftalat 420 A, having a melting range of 55-60 C., an acid number of -200 and being water clear in appearance and available from Chemische Werke, Albert, and the fatty acid modified alkyd resin available under the trade name Alftalat liti. 329/4 and having an acid es number of 80-90, viscosity, at 50% concentration in toluol, of (170 centipoises and containing about 50% fatty acid modication, which is available from Chemische Werke, Albert.
  • the water soluble paint systems may include in addition to the resins of the type above specified conventional pigments, flow irnprovers, softening agents and solvents including alcohols, glycols, etc., in addition to water, and such other ingredients may be present in the proportions conventionally used in such paint systems.
  • Example I An acidic zinc phosphate solution of the type conventionally employed to form a phosphate coating for use as a base for paint was compounded by admixing with water, zinc oxide, 75% phosphoric acid and nitric acid in quantities to produce a solution having an analysis of 0.14% Zn, 0.75% P04 and 1.8% NO3. The solution had a total acid of 10.1.
  • coatings were formed by spraying the solution on the surface of conventionally cleaned cold rolled steel panels, 4 x 6, in a contact time of about l minute.
  • the average coating weight produced was about 265 milligrams per square foot.
  • Some of the panels were then rinsed in a dilute aqueous hexavalent chromium-containing solution, formulated at 0.03% CrO3, removed and cold water rinsed.
  • Certain of the phosphate coated panels were rinsed in an aqueous ammonium hydroxide solution having a pH of 8.5, and a plurality of each of these panels were spray-coated with a water soluble paint having the following composition:
  • Example II A water soluble paint was formulated to contain 150 parts by weight melamine resin (Resydrol M-471), 95 parts titanium dioxide, 5 parts zinc sulfide, 15 parts isopropanol and 440 parts water.
  • Example III An acrylic polymer emulsion was prepared using Rhoplex AC-200 acrylic resin. This material as used contains 46% solids, a pH of 9-l0, has a bulking value of 0.110 gallon per pound of emulsion and 0.0985 gallon per pound of solid polymer. A spray formulation containing this resin was prepared containing, in pounds per gallon of water, 7.2 pounds Rhoplex AC-200 (46% solids), .36 pound isophorone, 2 pounds rutile titanium dioxide, .02 pound morpholine, 0.01 pound tributyl phosphate, 0.02 pound dimethyl amino ethanol, and 0.8 pound water. The resultant dispersion had a pH of about 9.5 and was colored slightly blue by adding a trace of phthalocyanine blue.
  • Example II Cold rolled steel panels, conventionally cleaned, were phosphate coated in the zinc phosphate solution specified above in Example I, water rinsed, and then rinsed in a dilute aqueous solution containing a mixture of ethylamine phosphate and ammonium hydroxide and having a pH of 8.0. After removal and drying, the panels were spray coated with the aqueous emulsion formulation above identified, and the baked at 350 for 30 minutes. An inspection of the coatings on the surfaces, after cooling, showed the surfaces to be coated with a smooth white continuous film free of undulations, conglomerates or other roughness.
  • the preliminary chemical treatment to which the metal surface is subjected may include aqueous acidic solutions which function as cleaners or aqueous acidic solutions which function to form an integrally bound chemically induced coating on the metal surface.
  • the rinsing step of this invention is useful following a preliminary contact of the metal surface with an aqueous acidic solution of phosphoric, chromic or oxalic acid or from the preliminary treatment of the surface with an aqueous acidic solution of zinc phosphate, manganese phosphate, one or more alkaline earth metal phosphates, or an alkali metal phosphate, including ammonium phosphate, or Zinc or manganese phosphate modified with an alkaline earth metal phosphate or an alkali metal phosphate including ammonium phosphate.
  • thermosetting or curing temperature for use in curing the water soluble paint, lacquer or varnish materials of this invention will vary with the particular material selected but, in general, a temperature in the range of 200 C. to about 300 C. is satisfactory.
  • a process for preparing a metal surface for receiving a water soluble paint film which comprises the steps of (1) contacting said surface with an aqueous acidic solution of at least one phosphate selected from the group consisting of zinc phosphate, manganese phosphate, alkaline earth metal phosphates and the alkali metal phosphates, (2) thereafter rinsing the surface of the metal from step (l) in an aqueous acidic solution of an acid selected from the group consisting of phosphoric, chromic and oxalic acids, (3) thereafter rinsing the surface of the metal from step (2) in an aqueous rinse solution of an amine selected from the group consisting of ammonia, diethylamine, triethylamine, triethanolamine, morpholine, cyclohexylamine, dicyclohexylamine, aminopropanol and aminoisobutanol, said rinse solution having a pH in the range of 7 to about l1, and (4) while said rinsed surface is wet
  • a process for preparing a metal surface for receiving a Water soluble paint ilm which comprises the steps of (1) contacting said surface with an aqueous -acidic solution of a material selected from the group consisting of phosphoric acid, chromic acid, oxalic acid, zinc phosphate, manganese phosphate, alkaline earth metal phosphates and alkali metal phosphates and mixtures of said phosphates and (2) thereafter rinsing the surface of the metal from step (1) in an aqueous rinse solution of an amine selected from the group consisting of ammonia, diethylamine, triethylamine, triethanolamine, morpholine, cyclohexylamine, dicyclohexylamine, aminopropanol and aminoisobutanol, said rinse solution having a pH in the range of 7 to about 11, and (3) While said rinsed surface is Wet, applying a Water soluble paint to said surface and curing said Water soluble paint to thereby form a continuous l
  • said amine solution includes at least one phosphate ester selectJ ed from the group consisting of monomethyl amine phos phate, ethyl amine phosphate, isopropyl amine phosphate, monoethanol amine phosphate, diamyl amine phosphate, 2 amino-Z-methyl-l-propanol amine phosphate, cyclohexyh amine phosphate, tertiary octyl amine phosphate land ethylene diamine phosphate.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Materials Engineering (AREA)
  • Wood Science & Technology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Application Of Or Painting With Fluid Materials (AREA)
  • Chemical Treatment Of Metals (AREA)
  • Paints Or Removers (AREA)
US178247A 1961-03-15 1962-03-08 Process for treating metal surfaces Expired - Lifetime US3154438A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DEM48404A DE1184593B (de) 1961-03-15 1961-03-15 Verfahren zur Nachspuelung von chemisch vorbehandelten Metallen vor der Lackierung mit in Wasser geloesten bzw. dispergierten Lacken

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US3154438A true US3154438A (en) 1964-10-27

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US (1) US3154438A (is")
BE (1) BE612027A (is")
CH (1) CH419775A (is")
DE (1) DE1184593B (is")
GB (1) GB929644A (is")
NL (2) NL275534A (is")

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3197344A (en) * 1962-04-23 1965-07-27 Hooker Chemical Corp Compositions and methods for forming coatings on metal surfaces
US3290235A (en) * 1965-12-02 1966-12-06 Glidden Co Electrodeposition of acidic resin with subsequent anodic electrolysis in dispersioncontaining metal treating oxyanions
US3364080A (en) * 1964-10-22 1968-01-16 Amchem Prod Method of improving the corrosion resistance of chromate conversion coated aluminum surface
US3368913A (en) * 1963-01-29 1968-02-13 Henkel & Cie Gmbh Process for the treatment of metal surfaces prior to enameling
US3391032A (en) * 1963-06-27 1968-07-02 Hooker Chemical Corp Alkaline rinse for chromatized aluminum
US3395053A (en) * 1964-11-17 1968-07-30 Nasa Usa Thermal control coating
US3484343A (en) * 1964-07-13 1969-12-16 Toyo Kohan Co Ltd Amine solution treatment of cathodically chromated metal surfaces
US3519458A (en) * 1966-03-01 1970-07-07 Hooker Chemical Corp Method for reducing the corrosion susceptibility of ferrous metal having fluxing agent residue
US3787246A (en) * 1970-07-07 1974-01-22 H Tagai Process for producing a protective color film on an aluminum substrate
US3973998A (en) * 1975-05-05 1976-08-10 Celanese Coatings & Specialties Company Rinsing solutions for acid cleaned iron and steel surfaces
US4048374A (en) * 1973-09-01 1977-09-13 Dynamit Nobel Aktiengesellschaft Functional organophosphonic acid esters as preservative adhesion promoting agents and coating for metals
US4590100A (en) * 1983-10-28 1986-05-20 The United States Of America As Represented By The Secretary Of The Navy Passivation of steel with aqueous amine solutions preparatory to application of non-aqueous protective coatings
WO1996009994A1 (en) * 1994-09-26 1996-04-04 E.R. Squibb & Sons, Inc. Stainless steel alkali treatment
US5766684A (en) * 1994-09-26 1998-06-16 Calgon Vestal, Inc. Stainless steel acid treatment
US10575520B2 (en) 2016-03-16 2020-03-03 Board Of Supervisors Of Louisiana State University And Agricultural And Mechanical College Cyclohexylamine-based compounds and uses thereof

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2418608A (en) * 1939-05-22 1947-04-08 Parker Rust Proof Co Corrosion-resistant metallic article and method of making the same
US2768103A (en) * 1952-03-18 1956-10-23 Heintz Mfg Co Method for coating metals
US2768104A (en) * 1952-03-25 1956-10-23 Heintz Mfg Co Method for coating iron

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2418608A (en) * 1939-05-22 1947-04-08 Parker Rust Proof Co Corrosion-resistant metallic article and method of making the same
US2768103A (en) * 1952-03-18 1956-10-23 Heintz Mfg Co Method for coating metals
US2768104A (en) * 1952-03-25 1956-10-23 Heintz Mfg Co Method for coating iron

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3197344A (en) * 1962-04-23 1965-07-27 Hooker Chemical Corp Compositions and methods for forming coatings on metal surfaces
US3368913A (en) * 1963-01-29 1968-02-13 Henkel & Cie Gmbh Process for the treatment of metal surfaces prior to enameling
US3391032A (en) * 1963-06-27 1968-07-02 Hooker Chemical Corp Alkaline rinse for chromatized aluminum
US3484343A (en) * 1964-07-13 1969-12-16 Toyo Kohan Co Ltd Amine solution treatment of cathodically chromated metal surfaces
US3364080A (en) * 1964-10-22 1968-01-16 Amchem Prod Method of improving the corrosion resistance of chromate conversion coated aluminum surface
US3395053A (en) * 1964-11-17 1968-07-30 Nasa Usa Thermal control coating
US3290235A (en) * 1965-12-02 1966-12-06 Glidden Co Electrodeposition of acidic resin with subsequent anodic electrolysis in dispersioncontaining metal treating oxyanions
US3519458A (en) * 1966-03-01 1970-07-07 Hooker Chemical Corp Method for reducing the corrosion susceptibility of ferrous metal having fluxing agent residue
US3787246A (en) * 1970-07-07 1974-01-22 H Tagai Process for producing a protective color film on an aluminum substrate
US4048374A (en) * 1973-09-01 1977-09-13 Dynamit Nobel Aktiengesellschaft Functional organophosphonic acid esters as preservative adhesion promoting agents and coating for metals
US3973998A (en) * 1975-05-05 1976-08-10 Celanese Coatings & Specialties Company Rinsing solutions for acid cleaned iron and steel surfaces
US4590100A (en) * 1983-10-28 1986-05-20 The United States Of America As Represented By The Secretary Of The Navy Passivation of steel with aqueous amine solutions preparatory to application of non-aqueous protective coatings
WO1996009994A1 (en) * 1994-09-26 1996-04-04 E.R. Squibb & Sons, Inc. Stainless steel alkali treatment
US5766684A (en) * 1994-09-26 1998-06-16 Calgon Vestal, Inc. Stainless steel acid treatment
US5858118A (en) * 1994-09-26 1999-01-12 Calgon Vestal, Inc. Stainless steel alkali treatment
US10575520B2 (en) 2016-03-16 2020-03-03 Board Of Supervisors Of Louisiana State University And Agricultural And Mechanical College Cyclohexylamine-based compounds and uses thereof

Also Published As

Publication number Publication date
DE1184593B (de) 1964-12-31
GB929644A (en) 1963-06-26
BE612027A (fr) 1962-04-16
NL131372C (is")
NL275534A (is")
CH419775A (de) 1966-08-31

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Owner name: HOOKER CHEMICALS & PLASTICS CORP 32100 STEPHENSON

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:OXY METAL INDUSTRIES CORPORATION;REEL/FRAME:003942/0016

Effective date: 19810317

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Free format text: CHANGE OF NAME;ASSIGNOR:HOOKER CHEMICAS & PLASTICS CORP.;REEL/FRAME:004126/0054

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