EP0215041B1 - Process for the phosphating of metal surfaces - Google Patents
Process for the phosphating of metal surfaces Download PDFInfo
- Publication number
- EP0215041B1 EP0215041B1 EP86901388A EP86901388A EP0215041B1 EP 0215041 B1 EP0215041 B1 EP 0215041B1 EP 86901388 A EP86901388 A EP 86901388A EP 86901388 A EP86901388 A EP 86901388A EP 0215041 B1 EP0215041 B1 EP 0215041B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- phosphating
- zinc
- bromate
- phosphate
- phosphating solutions
- 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.)
- Expired
Links
- 238000000034 method Methods 0.000 title claims abstract description 45
- 229910052751 metal Inorganic materials 0.000 title claims abstract description 27
- 239000002184 metal Substances 0.000 title claims abstract description 27
- NBIIXXVUZAFLBC-UHFFFAOYSA-K phosphate Chemical compound [O-]P([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-K 0.000 claims abstract description 25
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 22
- 239000011701 zinc Substances 0.000 claims abstract description 21
- 229910052725 zinc Inorganic materials 0.000 claims abstract description 20
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 claims abstract description 15
- SXDBWCPKPHAZSM-UHFFFAOYSA-M bromate Inorganic materials [O-]Br(=O)=O SXDBWCPKPHAZSM-UHFFFAOYSA-M 0.000 claims abstract description 15
- 239000002253 acid Substances 0.000 claims abstract description 14
- 229910052742 iron Inorganic materials 0.000 claims abstract description 11
- SXDBWCPKPHAZSM-UHFFFAOYSA-N bromic acid Chemical compound OBr(=O)=O SXDBWCPKPHAZSM-UHFFFAOYSA-N 0.000 claims abstract description 10
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 7
- 229910052783 alkali metal Inorganic materials 0.000 claims abstract description 7
- 239000010959 steel Substances 0.000 claims abstract description 7
- -1 with aqueous Substances 0.000 claims abstract description 7
- 238000004070 electrodeposition Methods 0.000 claims description 9
- ONMOULMPIIOVTQ-UHFFFAOYSA-M 3-Nitrobenzene sulphonate Chemical compound [O-][N+](=O)C1=CC=CC(S([O-])(=O)=O)=C1 ONMOULMPIIOVTQ-UHFFFAOYSA-M 0.000 claims description 7
- 238000005507 spraying Methods 0.000 claims description 6
- 238000000576 coating method Methods 0.000 claims description 5
- 230000002378 acidificating effect Effects 0.000 claims description 4
- 150000001768 cations Chemical class 0.000 claims description 4
- 238000007598 dipping method Methods 0.000 claims description 4
- 239000011248 coating agent Substances 0.000 claims description 2
- 150000002500 ions Chemical class 0.000 claims description 2
- 159000000000 sodium salts Chemical class 0.000 claims description 2
- 229910019142 PO4 Inorganic materials 0.000 abstract description 21
- 239000010452 phosphate Substances 0.000 abstract description 21
- ONMOULMPIIOVTQ-UHFFFAOYSA-N 98-47-5 Chemical compound OS(=O)(=O)C1=CC=CC([N+]([O-])=O)=C1 ONMOULMPIIOVTQ-UHFFFAOYSA-N 0.000 abstract 3
- 239000012190 activator Substances 0.000 abstract 1
- 239000010410 layer Substances 0.000 description 31
- LRXTYHSAJDENHV-UHFFFAOYSA-H zinc phosphate Chemical compound [Zn+2].[Zn+2].[Zn+2].[O-]P([O-])([O-])=O.[O-]P([O-])([O-])=O LRXTYHSAJDENHV-UHFFFAOYSA-H 0.000 description 11
- 229910000165 zinc phosphate Inorganic materials 0.000 description 11
- 230000015572 biosynthetic process Effects 0.000 description 6
- 239000003973 paint Substances 0.000 description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- XTEGARKTQYYJKE-UHFFFAOYSA-M Chlorate Chemical compound [O-]Cl(=O)=O XTEGARKTQYYJKE-UHFFFAOYSA-M 0.000 description 4
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 4
- 229910001335 Galvanized steel Inorganic materials 0.000 description 3
- 239000003795 chemical substances by application Substances 0.000 description 3
- 238000004140 cleaning Methods 0.000 description 3
- 239000007921 spray Substances 0.000 description 3
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 2
- 229910002651 NO3 Inorganic materials 0.000 description 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 description 2
- IOVCWXUNBOPUCH-UHFFFAOYSA-M Nitrite anion Chemical compound [O-]N=O IOVCWXUNBOPUCH-UHFFFAOYSA-M 0.000 description 2
- 229910052782 aluminium Inorganic materials 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 2
- 239000008397 galvanized steel Substances 0.000 description 2
- 238000007654 immersion Methods 0.000 description 2
- 238000010348 incorporation Methods 0.000 description 2
- 230000008595 infiltration Effects 0.000 description 2
- 238000001764 infiltration Methods 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- KJFMBFZCATUALV-UHFFFAOYSA-N phenolphthalein Chemical compound C1=CC(O)=CC=C1C1(C=2C=CC(O)=CC=2)C2=CC=CC=C2C(=O)O1 KJFMBFZCATUALV-UHFFFAOYSA-N 0.000 description 2
- 229910052708 sodium Inorganic materials 0.000 description 2
- 239000011734 sodium Substances 0.000 description 2
- 229910000680 Aluminized steel Inorganic materials 0.000 description 1
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 1
- VEQPNABPJHWNSG-UHFFFAOYSA-N Nickel(2+) Chemical compound [Ni+2] VEQPNABPJHWNSG-UHFFFAOYSA-N 0.000 description 1
- 230000003213 activating effect Effects 0.000 description 1
- 230000004913 activation Effects 0.000 description 1
- 229910001413 alkali metal ion Inorganic materials 0.000 description 1
- 229910000318 alkali metal phosphate Inorganic materials 0.000 description 1
- 150000001340 alkali metals Chemical class 0.000 description 1
- LFVGISIMTYGQHF-UHFFFAOYSA-N ammonium dihydrogen phosphate Chemical compound [NH4+].OP(O)([O-])=O LFVGISIMTYGQHF-UHFFFAOYSA-N 0.000 description 1
- 239000011260 aqueous acid Substances 0.000 description 1
- UDSAIICHUKSCKT-UHFFFAOYSA-N bromophenol blue Chemical compound C1=C(Br)C(O)=C(Br)C=C1C1(C=2C=C(Br)C(O)=C(Br)C=2)C2=CC=CC=C2S(=O)(=O)O1 UDSAIICHUKSCKT-UHFFFAOYSA-N 0.000 description 1
- 239000011575 calcium Substances 0.000 description 1
- 229910052791 calcium Inorganic materials 0.000 description 1
- 239000002738 chelating agent Substances 0.000 description 1
- BFGKITSFLPAWGI-UHFFFAOYSA-N chromium(3+) Chemical compound [Cr+3] BFGKITSFLPAWGI-UHFFFAOYSA-N 0.000 description 1
- JOPOVCBBYLSVDA-UHFFFAOYSA-N chromium(6+) Chemical compound [Cr+6] JOPOVCBBYLSVDA-UHFFFAOYSA-N 0.000 description 1
- 239000010941 cobalt Substances 0.000 description 1
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 1
- 229910001429 cobalt ion Inorganic materials 0.000 description 1
- 239000012141 concentrate Substances 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 239000008367 deionised water Substances 0.000 description 1
- 229910021641 deionized water Inorganic materials 0.000 description 1
- 238000007865 diluting Methods 0.000 description 1
- 230000009189 diving Effects 0.000 description 1
- 239000004519 grease Substances 0.000 description 1
- 229910001437 manganese ion Inorganic materials 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- STZCRXQWRGQSJD-GEEYTBSJSA-M methyl orange Chemical compound [Na+].C1=CC(N(C)C)=CC=C1\N=N\C1=CC=C(S([O-])(=O)=O)C=C1 STZCRXQWRGQSJD-GEEYTBSJSA-M 0.000 description 1
- 229940012189 methyl orange Drugs 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 229910001453 nickel ion Inorganic materials 0.000 description 1
- UJJUJHTVDYXQON-UHFFFAOYSA-N nitro benzenesulfonate Chemical compound [O-][N+](=O)OS(=O)(=O)C1=CC=CC=C1 UJJUJHTVDYXQON-UHFFFAOYSA-N 0.000 description 1
- 239000007800 oxidant agent Substances 0.000 description 1
- 229910052827 phosphophyllite Inorganic materials 0.000 description 1
- 238000005554 pickling Methods 0.000 description 1
- 159000000001 potassium salts Chemical class 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 239000011241 protective layer Substances 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 239000010802 sludge Substances 0.000 description 1
- XUXNAKZDHHEHPC-UHFFFAOYSA-M sodium bromate Chemical compound [Na+].[O-]Br(=O)=O XUXNAKZDHHEHPC-UHFFFAOYSA-M 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000004381 surface treatment Methods 0.000 description 1
- JUWGUJSXVOBPHP-UHFFFAOYSA-B titanium(4+);tetraphosphate Chemical compound [Ti+4].[Ti+4].[Ti+4].[O-]P([O-])([O-])=O.[O-]P([O-])([O-])=O.[O-]P([O-])([O-])=O.[O-]P([O-])([O-])=O JUWGUJSXVOBPHP-UHFFFAOYSA-B 0.000 description 1
- 238000004448 titration Methods 0.000 description 1
- 239000000080 wetting agent Substances 0.000 description 1
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
- C23C22/07—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 phosphates
- C23C22/08—Orthophosphates
- C23C22/18—Orthophosphates containing manganese cations
- C23C22/182—Orthophosphates containing manganese cations containing also zinc cations
- C23C22/184—Orthophosphates containing manganese cations containing also zinc cations containing also nickel cations
-
- 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
- C23C22/07—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 phosphates
- C23C22/08—Orthophosphates
- C23C22/12—Orthophosphates containing zinc cations
- C23C22/17—Orthophosphates containing zinc cations containing also organic acids
Definitions
- the invention relates to a process for phosphating metal surfaces, in particular iron and steel, with aqueous, acidic phosphating solutions which, in addition to zinc and phosphate ions, contain an accelerator combination of alkali metal bromate and m-nitrobenzenesulfonate.
- the new process is particularly suitable as a pretreatment of the metal surfaces for a subsequent cathodic electrocoating.
- Chlorate serves as an accelerator for these phosphating baths, optionally in combination with nitrite or nitrate.
- the thin and uniform phosphate coatings obtained in this way are particularly suitable as the basis for a subsequent electrocoating.
- such low-zinc phosphating processes are much more sensitive to changes in the process parameters due to the accelerators mentioned. This means that although high-quality phosphate layers result with fresh phosphating solutions, the corrosion protection deteriorates due to the irregularity of phosphate layers after the throughput of a large amount of metal surfaces, and in some cases no more useful protective layers are formed.
- DE-PS 1072055 describes a method for increasing the layer weight in the production of phosphate coatings. This increase in layer weight is achieved by adding a chelating agent, in particular based on polycarboxy-a-amino acids, to the phosphating solutions based on zinc phosphate.
- a chelating agent in particular based on polycarboxy-a-amino acids
- nitrate, nitrite and chlorate, bromate or nitrobenzenesulfonate can also be used as accelerators.
- this is not a so-called “low zinc process”.
- the process described in DE-PS 10 96152 also uses zinc phosphating solutions which have the conventional ratios of zinc to phosphate. These phosphating solutions additionally contain a certain amount of calcium and an oxidizing agent as an accelerator, bromate or m-nitrobenzenesulfonate being mentioned, among others. This process, which operates at relatively high temperatures, results in phosphating layers with layer weights in the range from 102 to 117 mg / dm 2 .
- DE-OS 2418 118 also describes a process for the preparation of phosphate coatings on iron and steel in which phosphating solutions based on alkali metal and / or ammonium orthophosphate are used. These phosphating baths additionally contain short-chain alkanolamines, nonionic wetting agents and an accelerating agent, bromate or m-nitrobenzenesulfonate being also mentioned, among others. However, this does not result in zinc phosphate layers on the metal surfaces.
- a major disadvantage of the conventional phosphating processes based on zinc phosphate or alkali metal phosphate discussed above - in comparison to the low-zinc phosphating process mentioned at the outset - is the fact that the phosphate layers formed here for subsequent cathodic electrocoating are less - due to the different chemical layer structure are suitable.
- thicker phosphate layers usually result, ie with a " higher layer weight, with relatively high bath temperatures being used.
- the present invention is based on the object of providing a phosphating process based on zinc phosphate solutions which ensures the formation of high-quality zinc phosphate layers which - with a low layer weight - are distinguished by a comparatively high iron content and are therefore particularly suitable for subsequent cathodic electrocoating .
- the temperatures of the phosphating baths used should be relatively low and these phosphating baths should remain “stable” even with a higher throughput on metal surfaces, ie. H. Ensure phosphate layers of consistent quality.
- the invention accordingly relates to a process for phosphating metal surfaces, in particular iron and steel, as pretreatment for a subsequent cathodic electrodeposition coating, by treating them with aqueous acid phosphating solutions which, in addition to zinc and phosphate ions, contain an alkali metal bromate as accelerator.
- the comparatively low bath temperature which is in the range from 35 to 40 ° C., preferably from 38 to 40 ° C.
- Another important point is the - compared to the known low-zinc processes - the relatively high content of free acid. This necessitates a stronger pickling reaction of the phosphating solutions on the metal surfaces to be treated, at the same time an increased incorporation of iron into the phosphate layer that forms and thus an improved layer formation overall.
- the phosphate layers formed in the process according to the invention have layer weights in the range from 1 to 1.65 g / m 2 .
- the advantages achieved with the method according to the invention also include significantly reduced sludge formation in the phosphating bath and increased stability thereof. This is to be understood to mean that even with a greater throughput of metal surfaces in the phosphating bath, the quality of the layers formed does not suffer any losses.
- the phosphating solutions used in the process according to the invention have a free acid score in the range from 0.5 to 1, preferably from 0.6 to 0.8.
- the total acid score is in the range from 18 to 25, preferably from 20 to 22.
- the free acid content is determined according to the score and the total acid score is determined according to the methods known here - cf. for example, “The Phosphating of Metals •, Leuze Verlag / Saulgau, 1974, pages 274 to 277:
- the free acid score corresponds to the consumption of ml n / 10 NaOH in the titration of 10 ml bath solution until the change in the first H 3 P0 4 stage (indicator methyl orange or bromophenol blue).
- the total acid score corresponds to the consumption of ml n / 10 NaOh when titrating 10 ml bath solution against phenolphthalein as an indicator.
- a combination of an alkali metal bromate and an m-nitrobenzenesulfonate is used as the accelerator, the amounts to be used and the weight ratio of bromate to m-nitrobenzenesulfonate to be within the limits given above.
- Alkali metal bromates which are suitable for this purpose are the sodium or potassium salts, preferably the sodium bromate.
- the sodium salt is preferably used as the m-nitrobenzenesulfonate.
- the content of zinc in the phosphating solutions according to the invention should be in the range of the above-mentioned limits; likewise the weight ratio of phosphate to zinc and the weight ratios of zinc or phosphate to bromate.
- metal cations can also be used in the process according to the invention. These are nickel or cobalt or manganese ions, with an additional content of nickel ions in the phosphating bath being preferred.
- concentration ranges of these metal cations to be used are:
- the phosphating solutions according to the invention can also contain 2 or 3 of these additional ion types, the total amount of these additional metal cations, however, not exceeding a total of 1.5 g / l.
- the method according to the invention is particularly suitable for phosphating metal surfaces made of iron and steel. However, it can also be used to advantage for phosphating metal surfaces made of zinc, aluminum, galvanized or aluminized steel.
- the phosphating solutions used in the process according to the invention can be prepared by dissolving the individual components in water. However, the phosphating solutions are preferably obtained by diluting concentrates which contain the active components in the same ratio as in the bath solutions. If necessary, is another Addition of alkali metal ions, preferably sodium, is necessary in order to bind the proportion of phosphate which exceeds the free acid content to be set.
- the phosphating solutions can be applied to the metal surfaces in the process according to the invention in a manner known per se, ie. H. by spraying, dipping or in a combined spraying / dipping process.
- the treatment times to be observed here depend on the respective application process: they are approximately 90 to 120 seconds in the spraying process; with the immersion process approx. 180 seconds and with the combined spray / immersion process approx. 20 to 30 seconds for spraying and approx. 150 to 180 seconds for diving.
- the usual, known treatment measures can be taken before and after the actual phosphating step.
- the metal surfaces to be phosphated are previously subjected to a cleaning treatment to remove grease and dirt, for example with the aid of alkaline cleaners. It can also be expedient - but is by no means necessary - to activate the metal surfaces in a manner known per se before the actual phosphating treatment.
- Corresponding activating agents based on titanium phosphate are suitable, for example.
- the metal surfaces are usually rinsed thoroughly with water. Rinsing with water and, if appropriate, aftertreatment with customary passivating agents, for example with chromium (VI) / chromium (III) solutions, also take place after the phosphating.
- the final treatment is then cathodic electrocoating, likewise in a manner known per se.
- the zinc phosphate layers with a high iron content obtained by the process according to the invention are generally suitable for all types of use of phosphate layers known to date, but they have particular advantages for subsequent cathodic electrocoating. Here they show a high resistance of the paint film against paint infiltration under corrosive stress as well as an excellent paint adhesion to the metallic surface.
- the phosphate layers obtained were finely crystalline and closed.
- Table 1 below are for the individual examples in each case the temperature of the phosphating solution, the type and duration - refer to the application layer as well as the weights of the phosphate layer produced.
- Sheets of electrolytically galvanized steel (7.5 ⁇ m thick) and sheets of aluminum (Al 99.5, semi-hard) were treated in the same way.
- the phosphate layers produced on electrolytically galvanized steel showed a slightly increased layer weight.
- the phosphated sheets were then cathodically electrocoated with different paint qualities and dried at elevated temperature.
- the dry film thickness of the paints was approx. 20 ⁇ m in each case.
- the painted sheets were then each provided with a parallel cut and subjected to a salt spray test in accordance with SS DIN 50021. After completion of the spray test, the infiltration of paint was determined and the formation of bubbles (blister) was assessed optically. Tables 2 and 3 below show the results obtained:
Landscapes
- Chemical & Material Sciences (AREA)
- General Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Chemical Treatment Of Metals (AREA)
- Electroplating And Plating Baths Therefor (AREA)
Abstract
Description
Die Erfindung betrifft ein Verfahren zur Phosphatierung von Metalloberflächen, insbesondere von Eisen und Stahl mit wäßrigen, sauren Phosphatierungslösungen, die neben Zink- und Phosphationen eine Beschleuniger-Kombination aus Alkalimetallbromat und m-Nitrobenzolsulfonat enthalten. Das neue Verfahren eignet sich insbesondere als Vorbehandlung der Metalloberflächen für eine nachfolgende kathodische Elektrotauchlackierung.The invention relates to a process for phosphating metal surfaces, in particular iron and steel, with aqueous, acidic phosphating solutions which, in addition to zinc and phosphate ions, contain an accelerator combination of alkali metal bromate and m-nitrobenzenesulfonate. The new process is particularly suitable as a pretreatment of the metal surfaces for a subsequent cathodic electrocoating.
Zur Phosphatierung von Metalloberflächen sind heute eine Vielzahl von Badtypen und damit verbundenen Verfahrensbedingungen bekannt. Die klassischen Zinkphosphatbäder arbeiten in einem vergleichsweise hohen Temperaturbereich von ca. 50 bis 60 °C und bilden auf der Metalloberfläche im wesentlichen eisenfreie Zinkphosphatschichten aus. In neuerer Zeit wurden jedoch zunehmend sogenannte Niedrig-Zink-Phosphatierverfahren eingesetzt, die - mit vergleichsweise zinkarmen und phosphatreichen Bädern gleichsfalls bei höheren Temperaturen - den Einbau von Eisen in die abgeschiedenen Zinkphosphatschichten und damit eine Ausbildung besonders erwünschter resistenter Zinkphosphatschichten ermöglichen.A large number of bath types and associated process conditions are known today for phosphating metal surfaces. The classic zinc phosphate baths work in a comparatively high temperature range of approx. 50 to 60 ° C and form essentially iron-free zinc phosphate layers on the metal surface. In recent times, however, so-called low-zinc phosphating processes have increasingly been used, which - with comparatively low-zinc and phosphate-rich baths and also at higher temperatures - enable the incorporation of iron into the deposited zinc phosphate layers and thus the formation of particularly desirable resistant zinc phosphate layers.
So werden beispielsweise in der DE-AS 22 32 067 wäßrige, saure Phosphatierlösungen zur Oberflächenbehandlung von Metallen beschrieben, die ein Gewichtsverhältnis von Zn : P04 = 1 : (12 bis 110) aufweisen. Als Beschleuniger für diese Phosphatierungsbäder dient Chlorat, gegebenenfalls in Kombination mit Nitrit oder Nitrat. Die hiermit gewonnenen dünnen und gleichmäßigen Phosphatüberzüge sind insbesondere als Grundlage für eine anschließende Elektrotauchlackierung geeignet. Derartige Niedrig-Zink-Phosphatierverfahren reagieren jedoch aufgrund der genannten Beschleuniger sehr viel empfindlicher auf Änderungen der Verfahrensparameter. Dies bedeutet, daß mit frischen Phosphatierlösungen zwar qualitativ hochwertige Phosphatschichten resultieren, daß sich jedoch nach Durchsatz einer größeren Menge von Metalloberflächen der Korrosionsschutz aufgrund unregelmäßiger Phosphatschichten qualitativ verschlechtert und sich zum Teil keine brauchbaren Schutzschichten mehr ausbilden.For example, DE-AS 22 32 067 describes aqueous acidic phosphating solutions for surface treatment of metals which have a weight ratio of Zn: P0 4 = 1: (12 to 110). Chlorate serves as an accelerator for these phosphating baths, optionally in combination with nitrite or nitrate. The thin and uniform phosphate coatings obtained in this way are particularly suitable as the basis for a subsequent electrocoating. However, such low-zinc phosphating processes are much more sensitive to changes in the process parameters due to the accelerators mentioned. This means that although high-quality phosphate layers result with fresh phosphating solutions, the corrosion protection deteriorates due to the irregularity of phosphate layers after the throughput of a large amount of metal surfaces, and in some cases no more useful protective layers are formed.
In der DE-PS 1072055 wird ein Verfahren zur Erhöhung des Schichtgewichtes bei der Herstellung von Phosphatüberzügen beschrieben. Diese Erhöhung des Schichtgewichtes wird durch den Zusatz eines Chelatbildners, insbesondere auf Basis von Polycarboxy-a-aminosäuren, zu den Phosphatierungslösungen auf Basis von Zinkphosphat erreicht. Als Beschleuniger kommen neben Nitrat, Nitrit und Chlorat auch Bromat oder Nitrobenzolsulfonat in Frage. Hierbei handelt es sich jedoch nicht um ein sogenanntes « Niedrig-Zink-Verfahren ».DE-PS 1072055 describes a method for increasing the layer weight in the production of phosphate coatings. This increase in layer weight is achieved by adding a chelating agent, in particular based on polycarboxy-a-amino acids, to the phosphating solutions based on zinc phosphate. In addition to nitrate, nitrite and chlorate, bromate or nitrobenzenesulfonate can also be used as accelerators. However, this is not a so-called “low zinc process”.
Auch bei dem in der DE-PS 10 96152 beschriebenen Verfahren wird mit Zinkphosphatierlösungen gearbeitet, die die herkömmlichen Verhältnisse von Zink zu Phosphat aufweisen. Diese Phosphatierlösungen enthalten zusätzlich eine bestimmte Menge an Calcium sowie ein Oxidationsmittel als Beschleuniger, wobei unter anderem Bromat oder m-Nitrobenzolsulfonat erwähnt sind. Bei diesem Verfahren, das bei relativ hohen Temperaturen arbeitet, resultieren Phosphatierungsschichten mit Schichtgewichten im Bereich von 102 bis 117 mg/dm2.The process described in DE-PS 10 96152 also uses zinc phosphating solutions which have the conventional ratios of zinc to phosphate. These phosphating solutions additionally contain a certain amount of calcium and an oxidizing agent as an accelerator, bromate or m-nitrobenzenesulfonate being mentioned, among others. This process, which operates at relatively high temperatures, results in phosphating layers with layer weights in the range from 102 to 117 mg / dm 2 .
In der DE-OS 2418 118 wird ferner ein Verfahren zur Herstellung von Phosphatüberzügen auf Eisen und Stahl beschrieben, bei dem Phosphatierlösungen auf Basis von Alkali- und/oder Ammoniumorthophosphat zur Anwendung kommen. Diese Phosphatierbäder enthalten zusätzlich kurzkettige Alkanolamine, nichtionogene Netzmittel und ein Beschleunigungsmittel, wobei unter anderen auch Bromat oder m-Nitrobenzolsulfonat genannt werden. Hierbei resultieren jedoch keine Zinkphosphatschichten auf den Metalloberflächen.DE-OS 2418 118 also describes a process for the preparation of phosphate coatings on iron and steel in which phosphating solutions based on alkali metal and / or ammonium orthophosphate are used. These phosphating baths additionally contain short-chain alkanolamines, nonionic wetting agents and an accelerating agent, bromate or m-nitrobenzenesulfonate being also mentioned, among others. However, this does not result in zinc phosphate layers on the metal surfaces.
Ein wesentlicher Nachteil der vorstehend erörterten herkömmlichen Phosphatierverfahren auf Basis von Zinkphosphat oder Alkalimetallphosphat - im Vergleich zu dem eingangs erwähnten Niedrig-Zink-Phosphatierverfahren - ist jedoch die Tatsache, daß die hierbei ausgebildeten Phosphatschichten für eine nachfolgende kathodische Elektrotauchlackierung - aufgrund des anderen chemischen Schichtaufbaus - weniger geeignet sind. Zudem resultieren meist dickere Phosphatschichten, d. h. mit einem " höheren Schichtgewicht, wobei relativ hohe Badtemperaturen zur Anwendung kommen.A major disadvantage of the conventional phosphating processes based on zinc phosphate or alkali metal phosphate discussed above - in comparison to the low-zinc phosphating process mentioned at the outset - is the fact that the phosphate layers formed here for subsequent cathodic electrocoating are less - due to the different chemical layer structure are suitable. In addition, thicker phosphate layers usually result, ie with a " higher layer weight, with relatively high bath temperatures being used.
Demgegenüber geht die vorliegende Erfindung von der Aufgabe aus, ein Phosphatierverfahren auf Basis von Zinkphosphatlösungen bereitzustellen, welches' die Ausbildung qualitativ hochwertiger Zinkphosphatschichten gewährleistet, die sich - bei geringem Schichtgewicht - durch einen vergleichsweise hohen Eisengehalt auszeichnen und sich somit insbesondere für eine nachfolgende kathodische Elektrotauchlackierung eignen. Gleichzeitig sollen die Temperaturen der zur Anwendung gelangenden Phosphatierbäder relativ gering sein und diese Phosphatierbäder auch bei höherem Durchsatz an Metalloberflächen « stabil » bleiben, d. h. Phosphatschichten gleichbleibender Qualität gewährleisten.In contrast, the present invention is based on the object of providing a phosphating process based on zinc phosphate solutions which ensures the formation of high-quality zinc phosphate layers which - with a low layer weight - are distinguished by a comparatively high iron content and are therefore particularly suitable for subsequent cathodic electrocoating . At the same time, the temperatures of the phosphating baths used should be relatively low and these phosphating baths should remain “stable” even with a higher throughput on metal surfaces, ie. H. Ensure phosphate layers of consistent quality.
Gegenstand der Erfindung ist dementsprechend ein Verfahren zum Phosphatieren von Metalloberflächen, insbesondere von Eisen und Stahl, als Vorbehandlung für eine nachfolgende kathodische Elektrotauchlackierung, durch deren Behandlung mit wäßrigen sauren Phosphatierungslösungen, die neben Zink- und Phosphationen ein Alkalimetallbromat als Beschleuniger enthalten.The invention accordingly relates to a process for phosphating metal surfaces, in particular iron and steel, as pretreatment for a subsequent cathodic electrodeposition coating, by treating them with aqueous acid phosphating solutions which, in addition to zinc and phosphate ions, contain an alkali metal bromate as accelerator.
Das neue Verfahren ist dadurch gekennzeichnet, daß man mit sauren Phosphatierungslösungen arbeitet, die den folgenden Bedingungen entsprechen :
Entscheidend für das erfindungsgemäße Verfahren und die damit erhaltenen Ergebnisse ist, daß durch die erfindungsgemäß ausgewählte Parameter-Kombination die Ausbildung von Zinkphosphatschichten mit einem hohen Eisengehalt ermöglicht wird. Diese Phosphatierungsschichten sind - vermutlich aufgrund ihres hohen Gehaltes an Phosphophyllit - insbesondere für eine nachfolgende kathodische Elektrotauchlackierung geeignet.It is crucial for the method according to the invention and the results obtained therewith that the combination of parameters selected according to the invention enables the formation of zinc phosphate layers with a high iron content. These phosphating layers are - particularly because of their high phosphophyllite content - particularly suitable for subsequent cathodic electrocoating.
Weitere Vorteile des erfindungsgemäßen Verfahrens sind ferner in der vergleichsweise geringen Badtemperatur zu sehen, die im Bereich von 35 bis 40 °C, vorzugsweise von 38 bis 40 °C, liegt. Ein weiterer wesentlicher Punkt ist der - im Vergleich zu den bekannten Niedrig-Zink-Verfahren - relativ hohe Gehalt an freier Säure. Dies bedingt eine stärkere Beizreaktion der Phosphatierungslösungen auf die zu behandelnden Metalloberflächen, gleichzeitig einen vermehrten Einbau von Eisen in die sich bildende Phosphatschicht und somit eine verbesserte Schichtausbildung insgesamt. Die beim Verfahren gemäß der Erfindung gebildeten Phosphatschichten weisen Schichtgewichte im Bereich von 1 bis 1,65 g/m2 auf.Further advantages of the method according to the invention can also be seen in the comparatively low bath temperature, which is in the range from 35 to 40 ° C., preferably from 38 to 40 ° C. Another important point is the - compared to the known low-zinc processes - the relatively high content of free acid. This necessitates a stronger pickling reaction of the phosphating solutions on the metal surfaces to be treated, at the same time an increased incorporation of iron into the phosphate layer that forms and thus an improved layer formation overall. The phosphate layers formed in the process according to the invention have layer weights in the range from 1 to 1.65 g / m 2 .
Zu den mit dem erfindungsgemäßen Verfahren erzielten Vorteilen zählt ferner eine deutlich verminderte Schlammbildung im Phosphatierungsbad sowie eine erhöhte Stabilität desselben. Hierunter ist zu verstehen, daß selbst bei größerem Durchsatz von Metalloberflächen im Phosphatierungsbad die Qualität der ausgebildeten Schichten keine Einbußen erleidet.The advantages achieved with the method according to the invention also include significantly reduced sludge formation in the phosphating bath and increased stability thereof. This is to be understood to mean that even with a greater throughput of metal surfaces in the phosphating bath, the quality of the layers formed does not suffer any losses.
Die beim erfindungsgemäßen Verfahren verwendeten Phosphatierungslösungen weisen eine Punktzahl der freien Säure im Bereich von 0,5 bis 1, vorzugsweise von 0,6 bis 0,8 auf. Gleichzeitig liegt die Punktzahl der Gesamtsäure im Bereich von 18 bis 25, vorzugsweise von 20 bis 22. Die Bestimmung des Gehaltes an freier Säure nach der Punktzahl sowie die Bestimmung der Punktzahl der Gesamtsäure erfolgt dabei nach den hier einschlägig bekannten Methoden - vgl. beispielsweise « Die Phosphatierung von Metallen •, Leuze Verlag/Saulgau, 1974, Seite 274 bis 277 :The phosphating solutions used in the process according to the invention have a free acid score in the range from 0.5 to 1, preferably from 0.6 to 0.8. At the same time, the total acid score is in the range from 18 to 25, preferably from 20 to 22. The free acid content is determined according to the score and the total acid score is determined according to the methods known here - cf. for example, “The Phosphating of Metals •, Leuze Verlag / Saulgau, 1974, pages 274 to 277:
Die Punktzahl der freien Säure entspricht dem Verbrauch an ml n/10 NaOH bei der Titration von 10 ml-Badlösung bis zum Umschlag der ersten H3P04-Stufe (Indikator Methylorange oder Bromphenolblau).The free acid score corresponds to the consumption of ml n / 10 NaOH in the titration of 10 ml bath solution until the change in the first H 3 P0 4 stage (indicator methyl orange or bromophenol blue).
Die Punktzahl der Gesamtsäure entspricht dem Verbrauch an ml n/10 NaOh bei der Titration von 10 ml-Badlösung gegen Phenolphthalein als Indikator.The total acid score corresponds to the consumption of ml n / 10 NaOh when titrating 10 ml bath solution against phenolphthalein as an indicator.
Beim Verfahren gemäß der Erfindung findet als Beschleuniger eine Kombination aus einem Alkalimetallbromat und einem m-Nitrobenzolsulfonat Verwendung, wobei die einzusetzenden Mengen und das Gewichtsverhältnis von Bromat zu m-Nitrobenzolsulfonat in den vorstehend angegebenen Grenzen liegen sollen. Alkalimetallbromate, die hierzu in Frage kommen, sind die Natrium- bzw. Kaliumsalze, vorzugsweise das Natriumbromat. Als m-Nitrobenzolsulfonat findet vorzugsweise das Natriumsalz Verwendung.In the process according to the invention, a combination of an alkali metal bromate and an m-nitrobenzenesulfonate is used as the accelerator, the amounts to be used and the weight ratio of bromate to m-nitrobenzenesulfonate to be within the limits given above. Alkali metal bromates which are suitable for this purpose are the sodium or potassium salts, preferably the sodium bromate. The sodium salt is preferably used as the m-nitrobenzenesulfonate.
Der Gehalt an Zink in den Phosphatierungslösungen gemäß der Erfindung soll im Bereich der vorstehend angegebenen Grenzen liegen ; gleichfalls das Gewichtsverhältnis von Phosphat zu Zink sowie die Gewichtsverhältnisse von Zink bzw. Phosphat zu Bromat.The content of zinc in the phosphating solutions according to the invention should be in the range of the above-mentioned limits; likewise the weight ratio of phosphate to zinc and the weight ratios of zinc or phosphate to bromate.
Im Rahmen des erfindungsgemäßen Verfahrens können neben Zink auch andere Metallkationen mitverwendet werden. Hierbei handelt es sich um Nickel- oder Kobalt- oder Mangan-lonen, wobei ein zusätzlicher Gehalt an Nickel-lonen im Phosphatierungsbad bevorzugt ist. Die anzuwendenden Konzentrationsbereiche dieser Metallkationen sind :
Gegebenenfalls können die Phosphatierungslösungen gemäß der Erfindung auch 2 oder 3 dieser zusätzlichen Ionen-Arten enthalten, wobei die Gesamtmenge dieser zusätzlichen Metallkationen jedoch insgesamt 1,5 g/I nicht übersteigen soll.If appropriate, the phosphating solutions according to the invention can also contain 2 or 3 of these additional ion types, the total amount of these additional metal cations, however, not exceeding a total of 1.5 g / l.
Das erfindungsgemäße Verfahren eignet sich insbesondere zum Phosphatieren von Metalloberflächen aus Eisen und Stahl. Mit Vorteil kann es jedoch auch zur Phosphatierung von Metalloberflächen aus Zink, Aluminium, verzinktem oder aluminiertem Stahl Anwendung finden.The method according to the invention is particularly suitable for phosphating metal surfaces made of iron and steel. However, it can also be used to advantage for phosphating metal surfaces made of zinc, aluminum, galvanized or aluminized steel.
Die beim erfindungsgemäßen Verfahren zur Anwendung gelangenden Phosphatierungslösungen können durch Auflösen der einzelnen Komponenten in Wasser hergestellt werden. Vorzugsweise werden die phosphatierungslösungen jedoch durch Verdünnen von Konzentraten, die die wirksamen Komponenten im gleichen Verhältnis wie in den Badlösungen enthalten, gewonnen. Gegebenenfalls ist ein weiterer Zusatz von Alkalimetallionen, vorzugsweise Natrium, erforderlich, um denjenigen Anteil an Phosphat zu binden, der den einzustellenden Gehalt an freier Säure übersteigt.The phosphating solutions used in the process according to the invention can be prepared by dissolving the individual components in water. However, the phosphating solutions are preferably obtained by diluting concentrates which contain the active components in the same ratio as in the bath solutions. If necessary, is another Addition of alkali metal ions, preferably sodium, is necessary in order to bind the proportion of phosphate which exceeds the free acid content to be set.
Das Aufbringen der Phosphatierungslösungen im Rahmen der erfindungsgemäßen Verfahrens auf die Metalloberflächen kann in an sich bekannter Weise erfolgen, d. h. durch Spritzen, Tauchen oder im kombinierten Spritz-/Tauchverfahren. Die hierbei einzuhaltenden Behandlungszeiten richten sich nach dem jeweiligen Auftragsverfahren : Sie betragen beim Spritzverfahren ca. 90 bis 120 Sekunden ; beim Tauchverfahren ca. 180 Sekunden und beim kombinierten Spritz-/Tauchverfahren ca. 20 bis 30 Sekunden zum Spritzen und ca. 150 bis 180 Sekunden zum Tauchen.The phosphating solutions can be applied to the metal surfaces in the process according to the invention in a manner known per se, ie. H. by spraying, dipping or in a combined spraying / dipping process. The treatment times to be observed here depend on the respective application process: they are approximately 90 to 120 seconds in the spraying process; with the immersion process approx. 180 seconds and with the combined spray / immersion process approx. 20 to 30 seconds for spraying and approx. 150 to 180 seconds for diving.
Vor und nach der eigentlichen Phosphatierungsstufe können die üblichen, an sich bekannten Behandlungsmaßnahmen ergriffen werden. So werden die zu phosphatierenden Metalloberflächen zuvor einer Reinigungsbehandlung zur Entfernung von Fett und Schmutz, beispielsweise mit Hilfe alkalischer Reiniger, unterworfen. Es kann auch zweckmäßig sein - ist aber keineswegs erforderlich - vor der eigentlichen Phosphatierungsbehandlung die Metalloberflächen in an sich bekannter Weise zu aktivieren. Hierzu sind beispielsweise entsprechende Aktivierungsmittel auf der Basis von Titanphosphat geeignet. Zwischen der Reinigungs- bzw. Aktivierungs-Stufe und dem eigentlichen Phosphatierschritt werden die Metalloberflächen üblicherweise gründlich mit Wasser gespült. Auch nach der Phosphatierung erfolgt eine Spülung mit Wasser sowie gegebenenfalls eine Nachbehandlung mit üblichen Passivierungsmitteln, beispielsweise mit Chrom(VI)/Chrom(III)-Lösungen. Als abschließende Behandlung erfolgt anschließend eine kathodische Elektrotauchlackierung, gleichfalls in an sich bekannter Weise.The usual, known treatment measures can be taken before and after the actual phosphating step. The metal surfaces to be phosphated are previously subjected to a cleaning treatment to remove grease and dirt, for example with the aid of alkaline cleaners. It can also be expedient - but is by no means necessary - to activate the metal surfaces in a manner known per se before the actual phosphating treatment. Corresponding activating agents based on titanium phosphate are suitable, for example. Between the cleaning or activation stage and the actual phosphating step, the metal surfaces are usually rinsed thoroughly with water. Rinsing with water and, if appropriate, aftertreatment with customary passivating agents, for example with chromium (VI) / chromium (III) solutions, also take place after the phosphating. The final treatment is then cathodic electrocoating, likewise in a manner known per se.
Die nach dem Verfahren gemäß der Erfindung gewonnenen Zinkphosphatschichten mit hohem Eisengehalt eignen sich generell für alle Anwendungsarten bis heute bekannter Phosphatschichten, sie weisen jedoch besondere Vorzüge für eine nachfolgende kathodische Elektrotauchlackierung auf. Hierbei zeigen sie eine hohe Beständigkeit des Lackfilmes gegen Lackunterwanderung bei korrosiver Beanspruchung sowie eine ausgezeichnete Lackhaftung zum metallischen Untergrund.The zinc phosphate layers with a high iron content obtained by the process according to the invention are generally suitable for all types of use of phosphate layers known to date, but they have particular advantages for subsequent cathodic electrocoating. Here they show a high resistance of the paint film against paint infiltration under corrosive stress as well as an excellent paint adhesion to the metallic surface.
Die nachfolgenden Beispiele dienen zur Erläuterung des erfindungsgemäßen Verfahrens.The following examples serve to explain the method according to the invention.
Es wurden Phosphatierungslösungen hergestellt, die jeweils die unter Beispiel 1 bis 7 angegebenen Komponenten enthielten :Phosphating solutions were prepared, each containing the components given in Examples 1 to 7:
Stahlbleche (Kaltbandblech St 1405), die zuvor mit einer alkalischen Reinigungslösung bei 50 °C während 3 Minuten durch Spritzbehandlung gereinigt und anschließend mit Wasser gespült worden waren, wurden mit den vorstehend angegebenen Phosphatierunglösungen behandelt. Anschließend wurde mit entionisiertem Wasser gespült und getrocknet.Steel sheets (cold rolled sheet St 1405), which had previously been spray-cleaned with an alkaline cleaning solution at 50 ° C. for 3 minutes and then rinsed with water, were treated with the phosphating solutions given above. It was then rinsed with deionized water and dried.
Die erhaltenen Phosphatschichten waren feinkristallin und geschlossen. Der nachstehenden Tabelle 1 sind für die einzelnen Beispiele jeweils die Temperatur der Phosphatierungslösung, Art und Dauer - des Aufbringens sowie die Schichtgewichte der erzeugten Phosphatschicht zu entnehmen.
In gleicher Weise wurden auch Bleche aus elektrolytisch verzinktem Stahl (Auflage 7,5 µm) sowie Bleche aus Aluminium (Al 99,5, halbhart) behandelt. Die auf elektrolytisch verzinktem Stahl erzeugten Phosphatschichten zeigten ein geringfügig erhöhtes Schichtgewicht.Sheets of electrolytically galvanized steel (7.5 µm thick) and sheets of aluminum (Al 99.5, semi-hard) were treated in the same way. The phosphate layers produced on electrolytically galvanized steel showed a slightly increased layer weight.
-Die phosphatierten Bleche wurden anschließend jeweils mit verschiedenen Lackqualitäten kathodisch elektrotauchlackiert und bei erhöhter Temperatur getrocknet. Die Trockenfilmdicke der Lacke betrug jeweils ca. 20 µm. Danach wurden die lackierten Bleche jeweils mit einem Parallelschnitt versehen und einem Salzsprühtest gemäß SS DIN 50021 unterworfen. Nach Abschluß des Sprühtestes wurde die Lack-Unterwanderung ermittelt und die Bildung von Bläschen (Blister) optisch beurteilt. Die nachfolgenden Tabellen 2 und 3 zeigen die erhaltenen Resultate :
Claims (7)
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| ES541129 | 1985-02-22 | ||
| ES541129A ES8606528A1 (en) | 1985-02-22 | 1985-02-22 | Process for the phosphating of metal surfaces. |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| EP0215041A1 EP0215041A1 (en) | 1987-03-25 |
| EP0215041B1 true EP0215041B1 (en) | 1988-08-17 |
Family
ID=8488822
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP86901388A Expired EP0215041B1 (en) | 1985-02-22 | 1986-02-20 | Process for the phosphating of metal surfaces |
Country Status (9)
| Country | Link |
|---|---|
| US (1) | US4708744A (en) |
| EP (1) | EP0215041B1 (en) |
| JP (1) | JPS62501919A (en) |
| BR (1) | BR8605484A (en) |
| DE (1) | DE3660553D1 (en) |
| ES (1) | ES8606528A1 (en) |
| PL (1) | PL254554A1 (en) |
| SU (1) | SU1560060A3 (en) |
| WO (1) | WO1986004931A1 (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3875459T2 (en) * | 1987-12-18 | 1993-03-25 | Nippon Paint Co Ltd | METHOD FOR PHOSPHATING METAL SURFACES. |
| US5525431A (en) * | 1989-12-12 | 1996-06-11 | Nippon Steel Corporation | Zinc-base galvanized sheet steel excellent in press-formability, phosphatability, etc. and process for producing the same |
| DE4330002C1 (en) * | 1993-09-04 | 1995-03-23 | Herberts Gmbh | Process for the coating of metallic substrates and application of the process |
| CN1041001C (en) * | 1993-09-06 | 1998-12-02 | 汉克尔股份两合公司 | Nickel-free method for phosphating metal surfaces |
| DE19540085A1 (en) * | 1995-10-27 | 1997-04-30 | Henkel Kgaa | Low nitrate, manganese-free zinc phosphating |
| CA2358625A1 (en) * | 2000-10-10 | 2002-04-10 | Henkel Corporation | Phosphate conversion coating |
| BRPI0811201A2 (en) * | 2007-06-07 | 2014-10-29 | Henkel Ag & Co Kgaa | COMPOSITION OF LIQUID MATTER FOR THE FORMATION OF A PHOSPHATE CONVERSION COATING ON A METAL SUBSTRATE, PROCESS FOR THE PRODUCTION OF A PHOSPHATE CONVERSION COATING, AND, MANUFACTURING ARTICLE. |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1072055B (en) * | 1952-08-28 | |||
| US2884351A (en) * | 1956-01-25 | 1959-04-28 | Parker Rust Proof Co | Method of cold rolling ferrous strip stock |
| DE1287891B (en) * | 1962-08-01 | 1969-01-23 | Metallgesellschaft Ag, 6000 Frankfurt | Process for applying a phosphate coating to surfaces made of iron or zinc |
| GB1542222A (en) * | 1977-01-06 | 1979-03-14 | Pyrene Chemical Services Ltd | Phosphate coating compositions |
| GB1591039A (en) * | 1977-05-03 | 1981-06-10 | Pyrene Chemical Services Ltd | Processes and compositions for coating metal surfaces |
| JPS5811513B2 (en) * | 1979-02-13 | 1983-03-03 | 日本ペイント株式会社 | How to protect metal surfaces |
| DE3101866A1 (en) * | 1981-01-22 | 1982-08-26 | Metallgesellschaft Ag, 6000 Frankfurt | METHOD FOR PHOSPHATING METALS |
| DE3118375A1 (en) * | 1981-05-09 | 1982-11-25 | Metallgesellschaft Ag, 6000 Frankfurt | METHOD FOR PHOSPHATING METALS AND ITS APPLICATION FOR PRE-TREATMENT FOR ELECTRO DIP PAINTING |
| US4498935A (en) * | 1981-07-13 | 1985-02-12 | Parker Chemical Company | Zinc phosphate conversion coating composition |
-
1985
- 1985-02-22 ES ES541129A patent/ES8606528A1/en not_active Expired
- 1985-07-15 PL PL25455485A patent/PL254554A1/en unknown
-
1986
- 1986-02-20 JP JP61501427A patent/JPS62501919A/en active Pending
- 1986-02-20 DE DE8686901388T patent/DE3660553D1/en not_active Expired
- 1986-02-20 WO PCT/EP1986/000084 patent/WO1986004931A1/en not_active Ceased
- 1986-02-20 EP EP86901388A patent/EP0215041B1/en not_active Expired
- 1986-02-20 BR BR8605484A patent/BR8605484A/en unknown
- 1986-02-24 US US06/832,923 patent/US4708744A/en not_active Expired - Fee Related
- 1986-10-21 SU SU864028345A patent/SU1560060A3/en active
Also Published As
| Publication number | Publication date |
|---|---|
| ES541129A0 (en) | 1986-04-01 |
| PL254554A1 (en) | 1986-08-26 |
| WO1986004931A1 (en) | 1986-08-28 |
| EP0215041A1 (en) | 1987-03-25 |
| JPS62501919A (en) | 1987-07-30 |
| US4708744A (en) | 1987-11-24 |
| DE3660553D1 (en) | 1988-09-22 |
| SU1560060A3 (en) | 1990-04-23 |
| ES8606528A1 (en) | 1986-04-01 |
| BR8605484A (en) | 1987-04-22 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| DE3879099T2 (en) | METHOD AND COMPOSITION FOR PRODUCING ZINC PHOSPHATE. | |
| EP0056881B1 (en) | Method of phosphating metals | |
| EP0064790A1 (en) | Method of phosphating metals, as well as its use in the electrodip painting pretreatment | |
| DE3234558C2 (en) | ||
| EP0796356B1 (en) | Method of applying phosphate coatings to metal surfaces | |
| EP1200641A1 (en) | Pretreatment of aluminum surfaces with chrome-free solutions | |
| DE3689442T2 (en) | Acidic, aqueous phosphate coating solutions for a process for phosphate coating of metallic surfaces. | |
| DE2100021A1 (en) | Process for applying phosphate layers to steel, iron and zinc surfaces | |
| EP0478648B1 (en) | Process for producing zinc phosphate coatings containing manganese and magnesium | |
| EP0155547B1 (en) | Process for the zinc-calcium phosphatizing of metal surfaces at a low treating temperature | |
| EP0359296B1 (en) | Phosphating process | |
| EP0069950B1 (en) | Process for phosphating metal surfaces | |
| EP0361375A1 (en) | Phosphate-coating process | |
| EP0111223B1 (en) | Process for phosphatizing metallic surfaces, and solutions for use therein | |
| EP0039093B1 (en) | Method of phosphating the surfaces of metals, and its use | |
| DE2739006C2 (en) | ||
| DE3245411C2 (en) | ||
| EP0931179B1 (en) | Method for phosphating a steel band | |
| WO2004101850A1 (en) | Pre-treatment of metal surfaces prior to painting | |
| DE19735314C2 (en) | Process for the pretreatment of components | |
| EP0215041B1 (en) | Process for the phosphating of metal surfaces | |
| DE2031358C3 (en) | Process for the production of protective layers on aluminum, iron and zinc by means of acidic solutions containing complex fluorides | |
| EP1019564A1 (en) | Method for phosphatizing a steel strip | |
| EP0461133B1 (en) | Process for producing zinc/barium phosphate coatings on metal surfaces | |
| EP0866888B1 (en) | Method of phosphating metal surfaces |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
| 17P | Request for examination filed |
Effective date: 19861112 |
|
| AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): BE DE FR GB IT NL SE |
|
| 17Q | First examination report despatched |
Effective date: 19871013 |
|
| GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
| AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): BE DE FR GB IT NL SE |
|
| REF | Corresponds to: |
Ref document number: 3660553 Country of ref document: DE Date of ref document: 19880922 |
|
| ET | Fr: translation filed | ||
| ITF | It: translation for a ep patent filed | ||
| GBT | Gb: translation of ep patent filed (gb section 77(6)(a)/1977) | ||
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: DE Payment date: 19890127 Year of fee payment: 4 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: SE Payment date: 19890208 Year of fee payment: 4 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: FR Payment date: 19890209 Year of fee payment: 4 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: NL Payment date: 19890228 Year of fee payment: 4 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: BE Payment date: 19890317 Year of fee payment: 4 |
|
| PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
| STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
| 26N | No opposition filed | ||
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: GB Effective date: 19900220 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: SE Effective date: 19900221 |
|
| ITTA | It: last paid annual fee | ||
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: BE Effective date: 19900228 |
|
| BERE | Be: lapsed |
Owner name: HENKEL K.G.A.A. Effective date: 19900228 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: NL Effective date: 19900901 |
|
| NLV4 | Nl: lapsed or anulled due to non-payment of the annual fee | ||
| GBPC | Gb: european patent ceased through non-payment of renewal fee | ||
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: FR Effective date: 19901031 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DE Effective date: 19901101 |
|
| REG | Reference to a national code |
Ref country code: FR Ref legal event code: ST |
|
| EUG | Se: european patent has lapsed |
Ref document number: 86901388.8 Effective date: 19901107 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: IT Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES;WARNING: LAPSES OF ITALIAN PATENTS WITH EFFECTIVE DATE BEFORE 2007 MAY HAVE OCCURRED AT ANY TIME BEFORE 2007. THE CORRECT EFFECTIVE DATE MAY BE DIFFERENT FROM THE ONE RECORDED. Effective date: 20050220 |