EP0624182A1 - Composition de revetement a auto-depot - Google Patents

Composition de revetement a auto-depot

Info

Publication number
EP0624182A1
EP0624182A1 EP93903012A EP93903012A EP0624182A1 EP 0624182 A1 EP0624182 A1 EP 0624182A1 EP 93903012 A EP93903012 A EP 93903012A EP 93903012 A EP93903012 A EP 93903012A EP 0624182 A1 EP0624182 A1 EP 0624182A1
Authority
EP
European Patent Office
Prior art keywords
liter
grams
ion
fluoride ion
coating composition
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP93903012A
Other languages
German (de)
English (en)
Inventor
Takumi Honda
Kazuhisa Naito
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Henkel Corp
Original Assignee
Henkel Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Henkel Corp filed Critical Henkel Corp
Publication of EP0624182A1 publication Critical patent/EP0624182A1/fr
Withdrawn legal-status Critical Current

Links

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
    • 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
    • C23C22/40—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 molybdates, tungstates or vanadates
    • C23C22/44—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 molybdates, tungstates or vanadates containing also fluorides or complex fluorides
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D5/00—Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced; Filling pastes
    • C09D5/08—Anti-corrosive paints
    • C09D5/088—Autophoretic paints

Definitions

  • the invention relates to an aqueous autodeposition coating composition in the form of an acidic coating 5 composition (pH approximately 1.6 to 5) that contains a water-dispersible or water-soluble organic film-forming resin; fluoride ions or fluoride ions and " complex fluoride ions; one or more ions selected from ions of the following metals: zinc, cobalt, manganese, nickel, iron, and
  • the aqueous autodeposition coating composition is capable of forming a highly corrosion-resistant, strongly adherent resin film on metal surfaces when brought into contact with the surface of a metal, for example, a ferriferous metal,
  • Autodeposition coating compositions are acidic coating compositions that contain an organic film-forming resin and form a resin film on a metal surface when brought into contact with the metal surface. Autodeposition coating compositions are disclosed in, for example,
  • a characteristic feature of the known coating compositions is their ability to lay down a resin film upon immersion of a clean metal surface in the particular coating composition. Moreover, the coating film's thickness and weight increase with immersion time. In the case of these compositions, the chemical activity of the coating composition overlying the metal surface (metal ion eluted from the metal surface by etching induces association of the resin particles with resulting deposition on the metal surface) results in the efficient deposition of a resin film on the metal surface without the application, as in electrodeposition, of an external electrical source.
  • a metal ion-containing coating composition is disclosed in Japanese Patent Publication Number Sho 52-35692. This publication discloses the use of a composition that contains a ferric ion-supplying iron compound to coat ferriferous metal.
  • a coating composition that contains various metal ions (not including the ferric ion) is disclosed in Japanese Patent Publication Number Sho 53-44949 for the coating of various- types of metal substrates.
  • the demands made on coating performance have recently become more severe, particularly with regard to adherence and corrosion resistance.
  • a rinse treatment with a chromium-containing solution or aqueous alkali solution, etc. may be implemented prior to film curing (prior to baking/drying) in order thereby to provide the ultimately produced film with better corrosion resistance and better adherence.
  • the presence of a chromium compound is particularly effective for enhancing film performance and particularly the corrosion resistance provided by the film.
  • the present invention provides an essentially chromium compound-free film which has much better adherence and corrosion resistance than the films formed by prior-art coating compositions, but which is produced without a rinse treatment (for example, with a chromium-containing solution) prior to film curing.
  • the aqueous autodeposition coating composition of the invention has a pH of about 1.6 to about 5 and contains (i) water-dispersible or water-soluble organic film-forming resin; (ii) at least one of fluoride ions or fluoride ions and complex fluoride ions; (i ⁇ ) additional metal ions of at least one metal selected from the group consisting of zinc, cobalt, manganese, nickel, iron, and aluminum; and (iv) at least one of tungstate ion and olybdate ion.
  • a highly adherent, strongly corrosion-resistant resin film is formed on the metal surface when the aqueous auto ⁇ deposition coating composition of the present invention is brought into contact with a metal surface, for example, the surface of ferriferous, zinciferous, aluminiferous, or magnesium-based metal.
  • composition of the invention provides films with a better adherence and corrosion resistance than the films afforded by prior autodeposition coating compositions due to an acidic coating composition (pH about 1.6 to about 5) that contains organic film-forming resin; fluoride ion or fluoride ion and complex fluoride ion; one or more additional metal ions selected from the group consisting of zinc, cobalt, manganese, nickel, iron, and aluminum; and also tungstate ion and/or molybdate ion.
  • the present invention provides a highly adherent, highly corrosion-resistant film without having to carry out a post-treatment (precure rinse treatment, for example, with a chromium-containing solution) that have heretofore been implemented for the purpose of improving the adherence and corrosion resistance of the films produced by autodepositing coating compositions.
  • a post-treatment precure rinse treatment, for example, with a chromium-containing solution
  • DETAILED DESCRIPTION OF THE INVENTION Resin of the type disclosed in Japanese Patent Application Sho 61-168673 is an example of resin highly suitable for use as the organic film-forming resin in the present invention.
  • the organic film-forming resin useful in the practice of the present invention is exemplified by the following: urethane resins, epoxy resins, polyester resins, and polymer resins composed of one or more monomers selected from methyl acrylate, ethyl acrylate, n-butyl acrylate,
  • the organic film-forming resin useful in the practice of the invention may be anionic, cationic, nonionic, or amphoteric and is not specifically restricted in this regard.
  • the content of resin solids in the coating composition preferably falls within the range of 5 to 550 g/L and more preferably falls within the range of 50 to 100 g/L.
  • Sources for the fluoride ion and complex fluoride ion useful in the practice of the invention are, for example, zirconium hydrogen fluoride, titanium hydrogen fluoride, silicon hydrogen fluoride, boron hydrogen fluoride, hydrofluoric acid, and the ammonium, lithium, sodium, and potassium salts of the preceding acids.
  • the content of fluoride or fluoride ion and complex fluoride ion in the coating composition preferably falls within the range of 0.1 to 5 g/L as fluorine and more preferably falls within the range of 0.5 to 3 g/L as fluorine.
  • the pH of the coating composition of the invention should be maintained within the range of about 1.6 to about 5. Formation of the resin film becomes problematic when the pH is substantially outside this range.
  • the pH of the coating composition may be regulated using one or more acids selected from inorganic acids such as the acids listed above as sources of fluoride and complex fluoride ion and their salts, as well as nitric acid, phosphoric acid, and boric acid; and organic acids selected from phytic acid and tannic acid.
  • inorganic acids such as the acids listed above as sources of fluoride and complex fluoride ion and their salts, as well as nitric acid, phosphoric acid, and boric acid
  • organic acids selected from phytic acid and tannic acid.
  • nitric acid, phosphoric acid, boric acid, phytic acid, or tannic acid has the effect of improving film adherence to the substrate.
  • the zinc, cobalt, manganese, nickel, iron, and aluminum metal ions useful in the practice of the invention can be supplied using the carbonates, nitrates, phosphates, sulfates, hydroxides, oxides, and chlorides of the corresponding metals.
  • the metal ion is taken into the resin film during film formation (deposition process) , and it functions as a crosslinker for the resin during the heating carried out during film drying and curing.
  • the metal ion bonds with the functional groups in the resin to bring about a substantial increase in the molecular weight of the resin and thereby improve the corrosion resistance of the film formed on the metal.
  • the additional metal ions are present in solution in the composition in the range of from about 0.1 to about 20 gram/liter preferably from about 0.2 to about 10 grams/liter and more preferably from about 0.3 to about 6 grams/liter.
  • a critical feature of the present invention is the additional presence of at least one of tungstate ion and molybdate ion in a coating composition that contains organic film-forming resin; fluoride and/or complex fluoride ion; and one or more ions selected from the ions of the following metals: zinc, cobalt, manganese, nickel, iron, and aluminum.
  • the tungstate ion and/or molybdate ion present in the aqueous autodeposition coating composition of the invention forms a complex with a portion of the aforementioned metal ions.
  • the metal (ion) in the complex appears to substitute for metal ion eluted from the surface of the metal . workpiece, which results in efficient deposition onto the surface of the metal workpiece and ultimately coverage of the metal surface together with the organic film-forming resin.
  • the chromium (ion) taken into the resin film is largely present relatively near the surface of the resin film.
  • the metal ion taken into the resin film is largely present not only within the resin film, but also in particular in the vicinity of the metal surface of the substrate to a much greater degree than for prior-art coating compositions. This results in the production of a film having excellent adherence and corrosion resistance.
  • the tungstate ion used in the present invention can be supplied in the form of tungstic acid, sodium tungstate, calcium tungstate, potassium tungstate, and the like.
  • the molybdate ion used in the present invention can be supplied in the form of molybdic acid, sodium molybdate, calcium molybdate, potassium molybdate, and the like.
  • the content of tungstate ion and molybdate ion - in the coating composition should be 0.1 to 5 g/L and is preferably 0.3 to 2 g/L.
  • the coating composition of the present invention may also contain an oxidant as an optional material.
  • the coating composition of the present invention can contain pigment to impart color to the film. Examples of the present invention and comparison examples are presented below. Composition Production Examples A through 0
  • Aqueous coating compositions were prepared using an acrylic emulsion (41.5% solids, Rhoplex WL-91 from the Rohm _ Haas Company) and the other components as reported in Table l (brought to a total of 1 L with de-ionized water) .
  • Examples 1 through 16 The aqueous coating compositions prepared in
  • composition Production Examples A through P were used in these examples.
  • the aqueous coating composition baths were held at approximately 20 ⁇ C to 22"C.
  • the aqueous coating composition prepared in Composition Production Example Q was used in the comparison examples.
  • the aqueous coating composition baths were held at approximately 20 ⁇ C to 22 ⁇ C.
  • the aqueous coating composition prepared in Composition Production Example Q was used in this comparison example.
  • the aqueous coating composition bath was held at approximately 20°C to 22*C.
  • the sample was immersed in an aqueous chromium- containing solution (Palene 60, trademark of Nihon Parkerizing Company, Limited) for 60 seconds at room temperature and then dried in an oven for 20 minutes at 180 ⁇ C.
  • the sample was subsequently submitted to the various tests, and the results of the performance testing of the test sheet are reported in Table 2. Test Methods and Evaluation Standards
  • a grid of one hundred 1 mm x 1 mm squares was cut in the test sheet and peeled with adhesive tape, and the number of remaining film squares was counted. This test was conducted both before and after immersion in water at 40"C for 240 hours. The pre-immersion results are reported in row a and the post-immersion results are reported in row b.
  • the test sheet was prepared by cutting a cross in the coating to reach the base metal, and the test sheet was then subjected to salt-spray testing in accordance with JIS Z-2371 (500 hours for the cold-rolled steel sheet, galvannealed hot-dipped zinc-plated steel sheet, and electrogalvanized steel sheet and 1,000 hours for the aluminum sheet). The test sheet was subsequently subjected to tape peeling, and the peel width from the cross cut (one side, mm) was measured.
  • the aqueous autodeposition coating composition of the present invention is environmentally advantageous because it does not contain chromium.
  • coatings with a much better adherence and corrosion resistance than the coatings obtained from prior-art coating compositions are formed by contacting metal surfaces with the aqueous autodeposition coating composition of the present invention. Furthermore, this is achieved without having to carry out a rinse treatment, for example, with a chromium-containing solution, prior to film curing.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Materials Engineering (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Metallurgy (AREA)
  • Mechanical Engineering (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Wood Science & Technology (AREA)
  • Paints Or Removers (AREA)
  • Application Of Or Painting With Fluid Materials (AREA)
  • Chemical Treatment Of Metals (AREA)

Abstract

Composition aqueuse de revêtement à auto-dépôt. Elle est essentiellement exempte de composés de chrome et forme un film présentant une adhérence et une résistance à la corrosion supérieures à celles des films obtenus jusqu'ici, mais n'exige aucun traitement par rinçage avec une solution contenant du chrome avant le durcissement. Ladite composition aqueuse de revêtement à auto-dépôt présente un pH compris entre 1,6 et 5 environ, et renferme (i), une résine filmogène organique et hydrosoluble ou dispersible dans l'eau; (ii) des ions de fluorure et/ou des ions de fluorure associés à des ions de fluorure complexes; (iii) des ions d'au moins un métal sélectionné parmi le zinc, le cobalt, le manganèse, le nickel, le fer et l'aluminium; et (iv) des ions de tungstate et/ou de molybdate.
EP93903012A 1992-01-31 1993-01-15 Composition de revetement a auto-depot Withdrawn EP0624182A1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP4040571A JPH05214266A (ja) 1992-01-31 1992-01-31 自己析出型水性コーティング組成物
JP40571/92 1992-01-31
PCT/US1993/000137 WO1993015154A1 (fr) 1992-01-31 1993-01-15 Composition de revetement a auto-depot

Publications (1)

Publication Number Publication Date
EP0624182A1 true EP0624182A1 (fr) 1994-11-17

Family

ID=12584167

Family Applications (1)

Application Number Title Priority Date Filing Date
EP93903012A Withdrawn EP0624182A1 (fr) 1992-01-31 1993-01-15 Composition de revetement a auto-depot

Country Status (8)

Country Link
EP (1) EP0624182A1 (fr)
JP (1) JPH05214266A (fr)
AU (1) AU3438393A (fr)
BR (1) BR9305766A (fr)
CA (1) CA2128095A1 (fr)
MX (1) MX9300330A (fr)
WO (1) WO1993015154A1 (fr)
ZA (1) ZA93532B (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL1000118C2 (nl) * 1995-04-11 1996-10-14 Adw Chem Prod Bv Chroomvrij bekledingspreparaat voor het behandelen van metaaloppervlakken en werkwijze onder toepassing daarvan.
EP4310223A1 (fr) 2022-07-18 2024-01-24 Henkel AG & Co. KGaA Rinçage par réaction alcaline pour revêtements autophorétiques décoratifs

Families Citing this family (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5328525A (en) * 1993-01-05 1994-07-12 Betz Laboratories, Inc. Method and composition for treatment of metals
DE19755421A1 (de) 1997-12-13 1999-06-17 Henkel Kgaa Gummi-Metall-Verbund
WO1999037722A1 (fr) 1998-01-27 1999-07-29 Lord Corporation Composition aqueuse de traitement de metaux
US7037385B2 (en) 1998-01-27 2006-05-02 Lord Corporation Aqueous metal treatment composition
US6476119B1 (en) 1998-01-27 2002-11-05 Lord Corporation Aqueous primer or coating
US6902766B1 (en) 2000-07-27 2005-06-07 Lord Corporation Two-part aqueous metal protection treatment
US7294211B2 (en) 2002-01-04 2007-11-13 University Of Dayton Non-toxic corrosion-protection conversion coats based on cobalt
US20030172998A1 (en) * 2002-03-14 2003-09-18 Gerald Wojcik Composition and process for the treatment of metal surfaces
JP5249819B2 (ja) * 2009-03-02 2013-07-31 日本パーカライジング株式会社 電着塗料組成物および電着塗装方法
WO2011061784A1 (fr) * 2009-11-17 2011-05-26 日本パーカライジング株式会社 Liquide de traitement de surface pour revêtement par autodéposition d'un matériau à base de fer et/ou à base de zinc et procédé de traitement de surface
WO2012087813A2 (fr) * 2010-12-20 2012-06-28 Henkel Ag & Co. Kgaa Revêtement brillant applicable par auto-déposition présentant un aspect amélioré et ses procédés d'application
EP2890830B1 (fr) 2012-08-29 2018-06-27 PPG Industries Ohio, Inc. Compositions de prétraitement du zirconium qui contiennent du molybdène, procédés associés permettant de traiter des substrats métalliques et substrats métalliques recouverts associés
KR102181792B1 (ko) 2012-08-29 2020-11-24 피피지 인더스트리즈 오하이오 인코포레이티드 리튬을 함유하는 지르코늄 전처리 조성물, 관련된 금속 기판 처리 방법 및 관련된 코팅된 금속 기판
JP6043689B2 (ja) * 2013-07-31 2016-12-14 日本パーカライジング株式会社 多種金属材料用自己析出型被覆組成物とその製造方法及び有機樹脂被膜を有する金属材料とその製造方法
KR20190043155A (ko) 2016-08-24 2019-04-25 피피지 인더스트리즈 오하이오 인코포레이티드 금속 기판을 처리하기 위한 알칼리성 조성물

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5344949B2 (fr) * 1973-03-02 1978-12-02
AT352843B (de) * 1978-04-27 1979-10-10 Vianova Kunstharz Ag Verfahren zur herstellung von waessrigen ueberzugsmittelemulsionen
EP0046268A3 (fr) * 1980-08-14 1982-08-04 Union Carbide Corporation Composition de revêtement anti-corrosion autodéposable
EP0312648A3 (fr) * 1983-07-25 1989-05-10 HENKEL CORPORATION (a Delaware corp.) Latex de chlorure de vinylidène en autodéposition et durcissement à basse température

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO9315154A1 *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL1000118C2 (nl) * 1995-04-11 1996-10-14 Adw Chem Prod Bv Chroomvrij bekledingspreparaat voor het behandelen van metaaloppervlakken en werkwijze onder toepassing daarvan.
EP4310223A1 (fr) 2022-07-18 2024-01-24 Henkel AG & Co. KGaA Rinçage par réaction alcaline pour revêtements autophorétiques décoratifs
WO2024017544A1 (fr) 2022-07-18 2024-01-25 Henkel Ag & Co. Kgaa Rinçage par réaction alcaline pour revêtements autophorétiques décoratifs

Also Published As

Publication number Publication date
WO1993015154A1 (fr) 1993-08-05
JPH05214266A (ja) 1993-08-24
BR9305766A (pt) 1997-01-28
CA2128095A1 (fr) 1993-08-05
MX9300330A (es) 1993-12-31
AU3438393A (en) 1993-09-01
ZA93532B (en) 1993-08-26

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