Classifications

• • 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
  • C23C18/00—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating
  • C23C18/16—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating by reduction or substitution, e.g. electroless plating
  • C23C18/18—Pretreatment of the material to be coated
  • C23C18/1803—Pretreatment of the material to be coated of metallic material surfaces or of a non-specific material surfaces
  • C23C18/1824—Pretreatment of the material to be coated of metallic material surfaces or of a non-specific material surfaces by chemical pretreatment
  • C23C18/1837—Multistep pretreatment
  • C23C18/1844—Multistep pretreatment with use of organic or inorganic compounds other than metals, first
• • 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
  • C23C22/05—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 using aqueous solutions
  • C23C22/06—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 using aqueous solutions using aqueous acidic solutions with pH less than 6
  • C23C22/34—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 using aqueous solutions using aqueous acidic solutions with pH less than 6 containing fluorides or complex fluorides
• • 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

Definitions

• the invention relates to a process for the pretreatment of metallic surfaces, in which the cleaned, pickled and decapitated surfaces are first brought into contact with an aqueous solution and / or dispersion of aluminum-zirconium complexes, the surfaces of a subsequent treatment with aqueous solutions, Subjects emulsions and / or dispersions of one or more inorganic and / or organic film formers before coating with organic materials.
• the conversion layers significantly improve the adhesion and the corrosion-inhibiting effect of subsequent coatings with organic materials, such as paints, powder layers or foils. Therefore, the conversion layers are used in particular on aluminum, its alloys and on zinc as corrosion-resistant coatings without a subsequent coating.
• Another one A well-known area of application of chromates and chromic acid is the rinsing of zinc phosphate and iron phosphate conversion layers on steel and galvanized steel.
• this aftertreatment brings about a significant improvement in the adhesion of subsequent coatings with organic materials and an increase in the corrosion resistance of the coated metallic surfaces.
• chromium (VI) compounds Due to the toxic properties of chromium (VI) compounds, the wastewater generated in the control and disposal of the baths must be subjected to a special, complex treatment.
• organometallic compounds Due to recent developments, however, is a class of substances for use in aqueous solutions for pretreating metals before coating with organic materials become interesting, which are organometallic compounds.
• organometallic compounds In the past, the use of organometallic compounds in aqueous solution was prohibited because practically all known representatives of this class of substances hydrolyzed to a greater or lesser extent in aqueous solution.
• US Pat. No. 4,650,526 describes a method for treating phosphated metal surfaces before coating them with organic materials.
• organometallic compounds in rinse solutions to improve the adhesion of subsequent organic coatings is described.
• These are aluminum-zircon complexes, which are sold by Cavedon Chemical Co. under the name "CAVCOMOD”.
• CAVCOMOD Cavedon Chemical Co.
• the preparation of the aluminum-zirconium complexes is described in US Patents 4,539,048 and 4,539,049.
• the starting point of the present invention was the aluminum-zirconium complexes described in US Pat. No. 4,650,526. It was found that treatment of aluminum with the aluminum-zirconium complexes alone did not achieve acceptable adhesion and corrosion protection values in comparison with a "classic" pretreatment based on chromium (VI) compounds.
• Another object of the present invention was to achieve acceptable adhesion and corrosion protection values for surfaces prior to coating with organic materials.
• the above-mentioned objects are achieved by the combined use of the above-mentioned aluminum-zirconium complexes with an organic and / or inorganic film former.
• conversion layers with very good adhesion and improved corrosion protection properties can be produced for subsequent organic coatings.
• the invention thus relates to a process for the pretreatment of metallic surfaces, the cleaned, pickled and decapitated surfaces first being brought into contact with an aqueous solution and / or dispersion of aluminum-zirconium complexes which, as the reaction product of a chelated aluminum unit, an organofunctional ligand and a zirconyl halide are available, the organofunctional ligand being chemically bound to the chelated aluminum unit and the zirconium unit, characterized in that the surfaces of a subsequent treatment with aqueous solutions, emulsions and / or dispersions of one or more inorganic and / or organic film former before coating with organic materials.
• metallic surfaces made of aluminum, aluminum alloys, zinc, cadmium, magnesium, steel and / or galvanized and alloy-galvanized steel are used.
• the above-mentioned aluminum-zirconium complexes are used in a concentration of 0.05 to 50 g / l as an aqueous solution and / or dispersion.
• the contact time is 1 sec to 5 min at a bath temperature of 10 to 60 ° C.
• organic film formers used are preferably aqueous solutions, emulsions and / or dispersions of polyacrylic acid, polyacrylates, polyesters, polyurethanes and / or polyepoxy compounds in a concentration of 0.01 to 2 g / l of the bath.
• the organic film formers can be brought into contact with the surfaces by spraying, dipping, flooding, rolling and / or rolling up.
• the contact time of the aqueous solutions, emulsions and / or dispersions containing the organic film formers in one embodiment is 1 sec to 5 min at a bath temperature in the range from 10 to 60.degree.
• inorganic film formers used are preferably aqueous solutions and / or dispersions of metal oxides in a concentration of 0.05 to 5 g / l.
• metal oxides which are selected from the group consisting of silicon oxide, titanium dioxide and / or aluminum oxide.
• the inorganic film formers are brought into contact with the metal surfaces to be coated in the form of aqueous solutions or dispersions in the course of 1 sec to 5 min at a temperature of 10 to 60 ° C.
• the inorganic film formers can be brought into contact by spraying, dipping, Flooding, rolling and / or rolling with the surface happen.
• free and / or complex fluorides are added to the solutions containing aluminum-zirconium complexes in a concentration of 0.01 to 1 g / l.
• zircoaluminate solution The active contents of the commercially available solutions (hereinafter zircoaluminate solution) are between 20 - 24%.
• the sheets were then subjected to adhesion and corrosion protection tests.
• Corrosion protection test Neutral salt spray test according to DIN 50021.
• a continuous cut is made on the metal sheets, down to the metal surface, on which the through Corrosion caused by infiltration is determined in mm.
• the sheets were dried as in reference example I according to 8).
• the sheets were painted in Reference Example I and subjected to the same adhesion and corrosion tests. The values are shown in Table 3.
• the concentration of the polyacrylic acid used was 1 g / l.
• the concentration of silicon dioxide in the immersion sink was 3 g / l.
• the concentration of silicon dioxide in the immersion sink was 1.5 g / l.
• the basic monomers are butyl acrylate and methyl methacrylate, the dispersion in the delivery form has a solids content of 50%, the pH is 2.2 ⁇ 0.5, the average particle diameter is 0.15 ⁇ m.
• Aerosil 200 As in Reference Example IV and Examples IV, but Degussa was used as Aerosil 200 silicon dioxide. Aerosil 200 has the following characteristics: Average size of the particles: 12 nm, surface according to BET 200 m2 / g, pH value in 4% aqueous dispersion: 3.6-4.3. Concentration: 3 g / l Time: 0.5 min Temp .: RT
• the adhesion of the organic coating is improved both compared to the untreated metal sheets and compared to the standard process.
• the corrosion protection values are significantly closer to the values achieved with the standard process than the values of the untreated sheets.

Landscapes

• Chemical & Material Sciences (AREA)
• Mechanical Engineering (AREA)
• Organic Chemistry (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• General Chemical & Material Sciences (AREA)
• Metallurgy (AREA)
• Inorganic Chemistry (AREA)
• Chemical Treatment Of Metals (AREA)
• Application Of Or Painting With Fluid Materials (AREA)
• Paints Or Removers (AREA)
• Laminated Bodies (AREA)
• Chemically Coating (AREA)
• Superconductors And Manufacturing Methods Therefor (AREA)

Priority Applications (1)

Applications Claiming Priority (2)

Publications (3)

Family

ID=6361748

Family Applications (1)

Country Status (12)

Cited By (5)

Families Citing this family (18)

Family Cites Families (9)

• 1988
  • 1988-08-27 DE DE3829154A patent/DE3829154A1/de not_active Withdrawn
• 1989
  • 1989-07-21 TR TR89/0885A patent/TR24778A/xx unknown
  • 1989-08-19 DE DE8989115352T patent/DE58903014D1/de not_active Expired - Fee Related
  • 1989-08-19 EP EP89115352A patent/EP0356855B1/fr not_active Expired - Lifetime
  • 1989-08-19 ES ES89115352T patent/ES2053886T3/es not_active Expired - Lifetime
  • 1989-08-19 AT AT89115352T patent/ATE83508T1/de not_active IP Right Cessation
  • 1989-08-21 MX MX017259A patent/MX170838B/es unknown
  • 1989-08-24 US US07/398,108 patent/US5026440A/en not_active Expired - Fee Related
  • 1989-08-24 CA CA000609287A patent/CA1332801C/fr not_active Expired - Fee Related
  • 1989-08-25 AU AU40802/89A patent/AU609327B2/en not_active Ceased
  • 1989-08-25 ZA ZA896526A patent/ZA896526B/xx unknown
  • 1989-08-28 BR BR898904315A patent/BR8904315A/pt unknown
  • 1989-08-28 JP JP1221396A patent/JPH02118081A/ja active Pending

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