EP3301205B1 - Acidic aqueous composition for preparing a corrosion resistant coating on a metal substrate, method for treating the metal substrate by using the composition - Google Patents
Acidic aqueous composition for preparing a corrosion resistant coating on a metal substrate, method for treating the metal substrate by using the composition Download PDFInfo
- Publication number
- EP3301205B1 EP3301205B1 EP17188823.3A EP17188823A EP3301205B1 EP 3301205 B1 EP3301205 B1 EP 3301205B1 EP 17188823 A EP17188823 A EP 17188823A EP 3301205 B1 EP3301205 B1 EP 3301205B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- range
- aluminium
- composition
- concentration
- acid
- 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.)
- Active
Links
- 239000000203 mixture Substances 0.000 title claims description 69
- 238000005260 corrosion Methods 0.000 title claims description 40
- 230000007797 corrosion Effects 0.000 title claims description 40
- 238000000034 method Methods 0.000 title claims description 38
- 239000000758 substrate Substances 0.000 title claims description 35
- 230000002378 acidificating effect Effects 0.000 title claims description 32
- 238000000576 coating method Methods 0.000 title claims description 29
- 239000011248 coating agent Substances 0.000 title claims description 24
- 229910052751 metal Inorganic materials 0.000 title description 26
- 239000002184 metal Substances 0.000 title description 26
- 239000011651 chromium Substances 0.000 claims description 44
- 238000011282 treatment Methods 0.000 claims description 40
- 239000004411 aluminium Substances 0.000 claims description 36
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 36
- 229910052782 aluminium Inorganic materials 0.000 claims description 35
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 28
- 229910052804 chromium Inorganic materials 0.000 claims description 25
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 claims description 23
- 229910000838 Al alloy Inorganic materials 0.000 claims description 19
- 239000002253 acid Substances 0.000 claims description 19
- 229910052726 zirconium Inorganic materials 0.000 claims description 18
- 150000003839 salts Chemical group 0.000 claims description 16
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 claims description 15
- 239000003381 stabilizer Substances 0.000 claims description 13
- QCWXUUIWCKQGHC-UHFFFAOYSA-N Zirconium Chemical compound [Zr] QCWXUUIWCKQGHC-UHFFFAOYSA-N 0.000 claims description 12
- BFGKITSFLPAWGI-UHFFFAOYSA-N chromium(3+) Chemical compound [Cr+3] BFGKITSFLPAWGI-UHFFFAOYSA-N 0.000 claims description 12
- 229910000831 Steel Inorganic materials 0.000 claims description 11
- 239000007864 aqueous solution Substances 0.000 claims description 11
- 239000010959 steel Substances 0.000 claims description 11
- KRHYYFGTRYWZRS-UHFFFAOYSA-M Fluoride anion Chemical compound [F-] KRHYYFGTRYWZRS-UHFFFAOYSA-M 0.000 claims description 10
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 claims description 10
- BVKZGUZCCUSVTD-UHFFFAOYSA-N carbonic acid Chemical compound OC(O)=O BVKZGUZCCUSVTD-UHFFFAOYSA-N 0.000 claims description 10
- -1 fluoride ions Chemical class 0.000 claims description 10
- 239000011701 zinc Substances 0.000 claims description 10
- 229910052725 zinc Inorganic materials 0.000 claims description 10
- 229910001297 Zn alloy Inorganic materials 0.000 claims description 9
- 229910000680 Aluminized steel Inorganic materials 0.000 claims description 7
- 239000004094 surface-active agent Substances 0.000 claims description 7
- 238000001035 drying Methods 0.000 claims description 6
- 239000003002 pH adjusting agent Substances 0.000 claims description 5
- 238000004026 adhesive bonding Methods 0.000 claims description 4
- 239000007800 oxidant agent Substances 0.000 claims description 4
- 150000004756 silanes Chemical class 0.000 claims description 4
- 150000002978 peroxides Chemical class 0.000 claims description 3
- 229920003169 water-soluble polymer Polymers 0.000 claims description 3
- 150000002823 nitrates Chemical class 0.000 claims description 2
- 125000000962 organic group Chemical group 0.000 claims 1
- 239000000243 solution Substances 0.000 description 38
- 238000012360 testing method Methods 0.000 description 26
- 239000010410 layer Substances 0.000 description 24
- JOPOVCBBYLSVDA-UHFFFAOYSA-N chromium(6+) Chemical compound [Cr+6] JOPOVCBBYLSVDA-UHFFFAOYSA-N 0.000 description 15
- 150000001875 compounds Chemical class 0.000 description 15
- 230000015572 biosynthetic process Effects 0.000 description 12
- 229910045601 alloy Inorganic materials 0.000 description 9
- 239000000956 alloy Substances 0.000 description 9
- 238000007739 conversion coating Methods 0.000 description 9
- 230000008569 process Effects 0.000 description 9
- 239000007921 spray Substances 0.000 description 9
- 239000000126 substance Substances 0.000 description 8
- 239000003973 paint Substances 0.000 description 7
- 229920000642 polymer Polymers 0.000 description 7
- 239000002585 base Substances 0.000 description 6
- 238000007598 dipping method Methods 0.000 description 6
- 238000007654 immersion Methods 0.000 description 6
- 238000006243 chemical reaction Methods 0.000 description 5
- 150000001845 chromium compounds Chemical class 0.000 description 5
- 238000012423 maintenance Methods 0.000 description 5
- 230000001590 oxidative effect Effects 0.000 description 5
- 238000002203 pretreatment Methods 0.000 description 5
- 238000012545 processing Methods 0.000 description 5
- 239000011241 protective layer Substances 0.000 description 5
- 239000008399 tap water Substances 0.000 description 5
- 235000020679 tap water Nutrition 0.000 description 5
- BLRPTPMANUNPDV-UHFFFAOYSA-N Silane Chemical compound [SiH4] BLRPTPMANUNPDV-UHFFFAOYSA-N 0.000 description 4
- 239000000654 additive Substances 0.000 description 4
- 230000000996 additive effect Effects 0.000 description 4
- 230000000052 comparative effect Effects 0.000 description 4
- 229920001577 copolymer Polymers 0.000 description 4
- 125000000524 functional group Chemical group 0.000 description 4
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 4
- 230000007935 neutral effect Effects 0.000 description 4
- 239000000047 product Substances 0.000 description 4
- 238000007789 sealing Methods 0.000 description 4
- 229910000077 silane Inorganic materials 0.000 description 4
- 229910001250 2024 aluminium alloy Inorganic materials 0.000 description 3
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 3
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 3
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 description 3
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 3
- 150000007513 acids Chemical class 0.000 description 3
- 230000001680 brushing effect Effects 0.000 description 3
- ZCDOYSPFYFSLEW-UHFFFAOYSA-N chromate(2-) Chemical compound [O-][Cr]([O-])(=O)=O ZCDOYSPFYFSLEW-UHFFFAOYSA-N 0.000 description 3
- 150000001844 chromium Chemical class 0.000 description 3
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 description 3
- 238000005238 degreasing Methods 0.000 description 3
- 238000005530 etching Methods 0.000 description 3
- 229910017604 nitric acid Inorganic materials 0.000 description 3
- 239000010802 sludge Substances 0.000 description 3
- 238000005507 spraying Methods 0.000 description 3
- 239000007858 starting material Substances 0.000 description 3
- 239000001117 sulphuric acid Substances 0.000 description 3
- 235000011149 sulphuric acid Nutrition 0.000 description 3
- FTBATIJJKIIOTP-UHFFFAOYSA-K trifluorochromium Chemical compound F[Cr](F)F FTBATIJJKIIOTP-UHFFFAOYSA-K 0.000 description 3
- 238000009736 wetting Methods 0.000 description 3
- BJEPYKJPYRNKOW-REOHCLBHSA-N (S)-malic acid Chemical compound OC(=O)[C@@H](O)CC(O)=O BJEPYKJPYRNKOW-REOHCLBHSA-N 0.000 description 2
- 241001163841 Albugo ipomoeae-panduratae Species 0.000 description 2
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 2
- QGZKDVFQNNGYKY-UHFFFAOYSA-O Ammonium Chemical compound [NH4+] QGZKDVFQNNGYKY-UHFFFAOYSA-O 0.000 description 2
- WRAGBEWQGHCDDU-UHFFFAOYSA-M C([O-])([O-])=O.[NH4+].[Zr+] Chemical class C([O-])([O-])=O.[NH4+].[Zr+] WRAGBEWQGHCDDU-UHFFFAOYSA-M 0.000 description 2
- KRKNYBCHXYNGOX-UHFFFAOYSA-K Citrate Chemical compound [O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O KRKNYBCHXYNGOX-UHFFFAOYSA-K 0.000 description 2
- RGHNJXZEOKUKBD-SQOUGZDYSA-N D-gluconic acid Chemical compound OC[C@@H](O)[C@@H](O)[C@H](O)[C@@H](O)C(O)=O RGHNJXZEOKUKBD-SQOUGZDYSA-N 0.000 description 2
- FEWJPZIEWOKRBE-JCYAYHJZSA-N Dextrotartaric acid Chemical compound OC(=O)[C@H](O)[C@@H](O)C(O)=O FEWJPZIEWOKRBE-JCYAYHJZSA-N 0.000 description 2
- AEMRFAOFKBGASW-UHFFFAOYSA-M Glycolate Chemical compound OCC([O-])=O AEMRFAOFKBGASW-UHFFFAOYSA-M 0.000 description 2
- AEMRFAOFKBGASW-UHFFFAOYSA-N Glycolic acid Chemical compound OCC(O)=O AEMRFAOFKBGASW-UHFFFAOYSA-N 0.000 description 2
- WOBHKFSMXKNTIM-UHFFFAOYSA-N Hydroxyethyl methacrylate Chemical compound CC(=C)C(=O)OCCO WOBHKFSMXKNTIM-UHFFFAOYSA-N 0.000 description 2
- JVTAAEKCZFNVCJ-UHFFFAOYSA-M Lactate Chemical class CC(O)C([O-])=O JVTAAEKCZFNVCJ-UHFFFAOYSA-M 0.000 description 2
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 2
- CERQOIWHTDAKMF-UHFFFAOYSA-N Methacrylic acid Chemical compound CC(=C)C(O)=O CERQOIWHTDAKMF-UHFFFAOYSA-N 0.000 description 2
- OFOBLEOULBTSOW-UHFFFAOYSA-N Propanedioic acid Natural products OC(=O)CC(O)=O OFOBLEOULBTSOW-UHFFFAOYSA-N 0.000 description 2
- 239000003929 acidic solution Substances 0.000 description 2
- 229910052783 alkali metal Inorganic materials 0.000 description 2
- BJEPYKJPYRNKOW-UHFFFAOYSA-N alpha-hydroxysuccinic acid Natural products OC(=O)C(O)CC(O)=O BJEPYKJPYRNKOW-UHFFFAOYSA-N 0.000 description 2
- JLDSOYXADOWAKB-UHFFFAOYSA-N aluminium nitrate Chemical compound [Al+3].[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O JLDSOYXADOWAKB-UHFFFAOYSA-N 0.000 description 2
- 150000003863 ammonium salts Chemical class 0.000 description 2
- 238000007743 anodising Methods 0.000 description 2
- 238000005422 blasting Methods 0.000 description 2
- 238000009835 boiling Methods 0.000 description 2
- KRVSOGSZCMJSLX-UHFFFAOYSA-L chromic acid Chemical compound O[Cr](O)(=O)=O KRVSOGSZCMJSLX-UHFFFAOYSA-L 0.000 description 2
- 229910021563 chromium fluoride Inorganic materials 0.000 description 2
- PHFQLYPOURZARY-UHFFFAOYSA-N chromium trinitrate Chemical compound [Cr+3].[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O PHFQLYPOURZARY-UHFFFAOYSA-N 0.000 description 2
- 239000011247 coating layer Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000002708 enhancing effect Effects 0.000 description 2
- 238000005187 foaming Methods 0.000 description 2
- 229920001519 homopolymer Polymers 0.000 description 2
- 238000007602 hot air drying Methods 0.000 description 2
- 230000002401 inhibitory effect Effects 0.000 description 2
- JVTAAEKCZFNVCJ-UHFFFAOYSA-N lactic acid Chemical compound CC(O)C(O)=O JVTAAEKCZFNVCJ-UHFFFAOYSA-N 0.000 description 2
- 239000011777 magnesium Substances 0.000 description 2
- 229910052749 magnesium Inorganic materials 0.000 description 2
- VZCYOOQTPOCHFL-UPHRSURJSA-N maleic acid Chemical compound OC(=O)\C=C/C(O)=O VZCYOOQTPOCHFL-UPHRSURJSA-N 0.000 description 2
- 239000011976 maleic acid Substances 0.000 description 2
- 239000001630 malic acid Substances 0.000 description 2
- 235000011090 malic acid Nutrition 0.000 description 2
- 238000009996 mechanical pre-treatment Methods 0.000 description 2
- XJRBAMWJDBPFIM-UHFFFAOYSA-N methyl vinyl ether Chemical compound COC=C XJRBAMWJDBPFIM-UHFFFAOYSA-N 0.000 description 2
- 229910052761 rare earth metal Inorganic materials 0.000 description 2
- PUZPDOWCWNUUKD-UHFFFAOYSA-M sodium fluoride Chemical compound [F-].[Na+] PUZPDOWCWNUUKD-UHFFFAOYSA-M 0.000 description 2
- 238000004381 surface treatment Methods 0.000 description 2
- 239000002562 thickening agent Substances 0.000 description 2
- VZCYOOQTPOCHFL-UHFFFAOYSA-N trans-butenedioic acid Natural products OC(=O)C=CC(O)=O VZCYOOQTPOCHFL-UHFFFAOYSA-N 0.000 description 2
- 238000003809 water extraction Methods 0.000 description 2
- WYTZZXDRDKSJID-UHFFFAOYSA-N (3-aminopropyl)triethoxysilane Chemical compound CCO[Si](OCC)(OCC)CCCN WYTZZXDRDKSJID-UHFFFAOYSA-N 0.000 description 1
- JHPBZFOKBAGZBL-UHFFFAOYSA-N (3-hydroxy-2,2,4-trimethylpentyl) 2-methylprop-2-enoate Chemical compound CC(C)C(O)C(C)(C)COC(=O)C(C)=C JHPBZFOKBAGZBL-UHFFFAOYSA-N 0.000 description 1
- 229920002818 (Hydroxyethyl)methacrylate Polymers 0.000 description 1
- SMZOUWXMTYCWNB-UHFFFAOYSA-N 2-(2-methoxy-5-methylphenyl)ethanamine Chemical compound COC1=CC=C(C)C=C1CCN SMZOUWXMTYCWNB-UHFFFAOYSA-N 0.000 description 1
- NIXOWILDQLNWCW-UHFFFAOYSA-N 2-Propenoic acid Natural products OC(=O)C=C NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 1
- GCGWQXSXIREHCF-UHFFFAOYSA-N 2-[bis(2-hydroxyethyl)amino]ethanol;zirconium Chemical compound [Zr].OCCN(CCO)CCO GCGWQXSXIREHCF-UHFFFAOYSA-N 0.000 description 1
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical class [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 1
- 229910021564 Chromium(III) fluoride Inorganic materials 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- RGHNJXZEOKUKBD-UHFFFAOYSA-N D-gluconic acid Natural products OCC(O)C(O)C(O)C(O)C(O)=O RGHNJXZEOKUKBD-UHFFFAOYSA-N 0.000 description 1
- IMROMDMJAWUWLK-UHFFFAOYSA-N Ethenol Chemical compound OC=C IMROMDMJAWUWLK-UHFFFAOYSA-N 0.000 description 1
- 229910000640 Fe alloy Inorganic materials 0.000 description 1
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical compound F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 description 1
- 229910001335 Galvanized steel Inorganic materials 0.000 description 1
- 229910003899 H2ZrF6 Inorganic materials 0.000 description 1
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 1
- 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 1
- 229910020148 K2ZrF6 Inorganic materials 0.000 description 1
- 229910001209 Low-carbon steel Inorganic materials 0.000 description 1
- 239000002202 Polyethylene glycol Substances 0.000 description 1
- 229920002125 Sokalan® Polymers 0.000 description 1
- FEWJPZIEWOKRBE-UHFFFAOYSA-N Tartaric acid Natural products [H+].[H+].[O-]C(=O)C(O)C(O)C([O-])=O FEWJPZIEWOKRBE-UHFFFAOYSA-N 0.000 description 1
- QYKIQEUNHZKYBP-UHFFFAOYSA-N Vinyl ether Chemical compound C=COC=C QYKIQEUNHZKYBP-UHFFFAOYSA-N 0.000 description 1
- 229910000611 Zinc aluminium Inorganic materials 0.000 description 1
- UEUMIMKGIUYUGH-UHFFFAOYSA-H [F-].[F-].[F-].[F-].[F-].[F-].[Zr+6] Chemical compound [F-].[F-].[F-].[F-].[F-].[F-].[Zr+6] UEUMIMKGIUYUGH-UHFFFAOYSA-H 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 239000012790 adhesive layer Substances 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 229910001515 alkali metal fluoride Inorganic materials 0.000 description 1
- 150000008044 alkali metal hydroxides Chemical class 0.000 description 1
- 229910001413 alkali metal ion Inorganic materials 0.000 description 1
- 150000001340 alkali metals Chemical class 0.000 description 1
- 150000001412 amines Chemical class 0.000 description 1
- 150000001413 amino acids Chemical class 0.000 description 1
- 125000003277 amino group Chemical group 0.000 description 1
- 229910021529 ammonia Inorganic materials 0.000 description 1
- 125000000129 anionic group Chemical group 0.000 description 1
- 239000003945 anionic surfactant Substances 0.000 description 1
- 150000001450 anions Chemical class 0.000 description 1
- KGBXLFKZBHKPEV-UHFFFAOYSA-N boric acid Chemical compound OB(O)O KGBXLFKZBHKPEV-UHFFFAOYSA-N 0.000 description 1
- 239000004327 boric acid Substances 0.000 description 1
- 230000000711 cancerogenic effect Effects 0.000 description 1
- 150000001732 carboxylic acid derivatives Chemical class 0.000 description 1
- 125000002843 carboxylic acid group Chemical group 0.000 description 1
- 231100000315 carcinogenic Toxicity 0.000 description 1
- 239000013043 chemical agent Substances 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 229910001430 chromium ion Inorganic materials 0.000 description 1
- GRWVQDDAKZFPFI-UHFFFAOYSA-H chromium(III) sulfate Chemical compound [Cr+3].[Cr+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O GRWVQDDAKZFPFI-UHFFFAOYSA-H 0.000 description 1
- 235000015165 citric acid Nutrition 0.000 description 1
- 150000001860 citric acid derivatives Chemical class 0.000 description 1
- 238000000975 co-precipitation Methods 0.000 description 1
- 230000000536 complexating effect Effects 0.000 description 1
- 239000008139 complexing agent Substances 0.000 description 1
- 238000010924 continuous production Methods 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000010790 dilution Methods 0.000 description 1
- 239000012895 dilution Substances 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 125000003700 epoxy group Chemical group 0.000 description 1
- MYICUKNZGKTMND-UHFFFAOYSA-N ethanol;zirconium Chemical class [Zr].CCO.CCO.CCO MYICUKNZGKTMND-UHFFFAOYSA-N 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000004744 fabric Substances 0.000 description 1
- 239000012467 final product Substances 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 150000002222 fluorine compounds Chemical class 0.000 description 1
- AWJWCTOOIBYHON-UHFFFAOYSA-N furo[3,4-b]pyrazine-5,7-dione Chemical compound C1=CN=C2C(=O)OC(=O)C2=N1 AWJWCTOOIBYHON-UHFFFAOYSA-N 0.000 description 1
- 239000008397 galvanized steel Substances 0.000 description 1
- 230000008570 general process Effects 0.000 description 1
- 239000000174 gluconic acid Substances 0.000 description 1
- 235000012208 gluconic acid Nutrition 0.000 description 1
- 229910052735 hafnium Inorganic materials 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 125000004435 hydrogen atom Chemical group [H]* 0.000 description 1
- IXCSERBJSXMMFS-UHFFFAOYSA-N hydrogen chloride Substances Cl.Cl IXCSERBJSXMMFS-UHFFFAOYSA-N 0.000 description 1
- 229910000041 hydrogen chloride Inorganic materials 0.000 description 1
- 229910000040 hydrogen fluoride Inorganic materials 0.000 description 1
- 150000004679 hydroxides Chemical class 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 1
- 239000004922 lacquer Substances 0.000 description 1
- 239000004310 lactic acid Substances 0.000 description 1
- 235000014655 lactic acid Nutrition 0.000 description 1
- 150000007522 mineralic acids Chemical class 0.000 description 1
- 239000000178 monomer Substances 0.000 description 1
- 239000002736 nonionic surfactant Substances 0.000 description 1
- 150000007524 organic acids Chemical class 0.000 description 1
- 235000005985 organic acids Nutrition 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 238000010979 pH adjustment Methods 0.000 description 1
- 238000005554 pickling Methods 0.000 description 1
- 239000004584 polyacrylic acid Substances 0.000 description 1
- 229920001223 polyethylene glycol Polymers 0.000 description 1
- 229920002451 polyvinyl alcohol Polymers 0.000 description 1
- 235000019422 polyvinyl alcohol Nutrition 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 239000011253 protective coating Substances 0.000 description 1
- 150000002910 rare earth metals Chemical class 0.000 description 1
- 230000002829 reductive effect Effects 0.000 description 1
- 238000005480 shot peening Methods 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 239000011775 sodium fluoride Substances 0.000 description 1
- 235000013024 sodium fluoride Nutrition 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 241000894007 species Species 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 239000000725 suspension Substances 0.000 description 1
- 235000002906 tartaric acid Nutrition 0.000 description 1
- 239000011975 tartaric acid Substances 0.000 description 1
- 229940095064 tartrate Drugs 0.000 description 1
- 125000003396 thiol group Chemical group [H]S* 0.000 description 1
- 229910052719 titanium Inorganic materials 0.000 description 1
- 231100000331 toxic Toxicity 0.000 description 1
- 230000002588 toxic effect Effects 0.000 description 1
- 231100000419 toxicity Toxicity 0.000 description 1
- 230000001988 toxicity Effects 0.000 description 1
- QQQSFSZALRVCSZ-UHFFFAOYSA-N triethoxysilane Chemical compound CCO[SiH](OCC)OCC QQQSFSZALRVCSZ-UHFFFAOYSA-N 0.000 description 1
- 229960004418 trolamine Drugs 0.000 description 1
- 229960000834 vinyl ether Drugs 0.000 description 1
- 125000000391 vinyl group Chemical group [H]C([*])=C([H])[H] 0.000 description 1
- ZTWTYVWXUKTLCP-UHFFFAOYSA-N vinylphosphonic acid Chemical compound OP(O)(=O)C=C ZTWTYVWXUKTLCP-UHFFFAOYSA-N 0.000 description 1
- NLVXSWCKKBEXTG-UHFFFAOYSA-N vinylsulfonic acid Chemical compound OS(=O)(=O)C=C NLVXSWCKKBEXTG-UHFFFAOYSA-N 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
- 150000003752 zinc compounds Chemical class 0.000 description 1
- 150000003754 zirconium Chemical class 0.000 description 1
- 229910021512 zirconium (IV) hydroxide Inorganic materials 0.000 description 1
- 150000003755 zirconium compounds Chemical class 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
- C23C22/34—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
- C23C22/05—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
- 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
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D11/00—Electrolytic coating by surface reaction, i.e. forming conversion layers
- C25D11/02—Anodisation
- C25D11/04—Anodisation of aluminium or alloys based thereon
- C25D11/18—After-treatment, e.g. pore-sealing
- C25D11/24—Chemical after-treatment
- C25D11/246—Chemical after-treatment for sealing layers
-
- 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
- C23C2222/00—Aspects relating to chemical surface treatment of metallic material by reaction of the surface with a reactive medium
- C23C2222/10—Use of solutions containing trivalent chromium but free of hexavalent chromium
Definitions
- the invention relates to an acidic aqueous composition for preparing a corrosion resistant coating on a metal substrate, a method of providing a corrosion resistant coating on a metal substrate, as well as a post-treatment composition, in particular for use in said method.
- an aqueous solution for forming a protective coating on a metal surface includes Cr 2 (GF 6 ), in which G is a Group IV-B element (Zr, Ti or Hf), in particular Cr 2 (ZrF 6 ) 3 at least one polymer having a plurality of carboxylic acid groups such as polyacrylic acid and copolymers of methyl vinyl ether and maleic acid, and at least one polymer having a plurality of hydroxyl groups for example polyvinyl alcohols and homopolymers or copolymers of hydroxyethyl methacrylate, and/or at least one polymer having a plurality of both carboxylic acid and hydroxyl acid groups exemplified by free-radical copolymers of hydroxyl-ethyl methacrylate and methacrylic acid, wherein the composition contains less than 500 ppm of alkali metal ions and less than 200 ppm of halide ions relative to chromium.
- G is a Group IV-B element (Zr,
- the Zr : Cr molar ratio is typically determined by the stoichiometry of the compound, but due to the optional presence of other components the weight ratio Zr : Cr is typically in the range of 2.4 : 1 - 3.0 : 1, most typically 2.6:1 -2.8:1.
- Any metal may be treated, with apparently good results being obtained on zinc, zinc alloy, aluminium and aluminium alloy surfaces.
- organo-functional silanes such as aminoproyl triethoxysilane may improve adhesion of subsequently applied coatings such as paints) to the treated surfaces, while maintaining good corrosion results.
- the pH of a treatment solution comprising the above polymers is in a range from 2.5 - 4.0, more typically 2.8-3.2.
- US 6375726 B1 has disclosed an acidic aqueous solution for the protection and surface treatment of aluminium, aluminium alloys and coated aluminium substrates against corrosion.
- the solution comprises at least one trivalent chromium salt such as trivalent chromium sulphate, at least one alkali metal hexafluorozirconate in combination with at least one water soluble or dispersible thickening agent and a water soluble surfactant.
- the corrosion resistant aluminium substrates of this invention have improved adhesion for overlaying coatings e.g. paints and a lower electrical resistance contact.
- WO 2006/088519 A2 discloses an acidic aqueous solution for treating metal substrates, such as aluminium alloy or iron alloy or a metal substrate having a pre-existing metal coating for example anodized aluminium to improve the adhesion bonding and corrosion protection, which comprises water soluble trivalent chromium compounds, fluorozirconates, fluorometallic compounds, zinc compounds, thickeners, surfactants, and at least about 0.001 mole per litre of the acidic solution of at least one polyhydroxy and/or carboxylic compound as the stabilizing agent for the aqueous solution.
- the carboxylic compounds contain one or more carboxylic functional groups having the formula R-COO- wherein R is hydrogen or a lower molecular weight organic radical or functional group, and can be used in the form of their acids or salts.
- the stabilizers are said to result in improved shelf-life and working stability of the solutions. According to this document after treating with the acid aqueous solution, application of a strong oxidizing solution can yield a film having additional corrosion resistance, which is presumed to be due to the formation of hexavalent chromium in the film derived from the trivalent chromium.
- an acidic, aqueous composition that contains a trivalent chromium compound, an organo-functional silane, and a compound of a group IV-B element, is known from US 2009/0280253 A1 .
- the composition is said to protect metal surfaces, preferably aluminium and aluminium alloys, against corrosion and improves their paint adhesion.
- the trivalent chromium compound may comprise chromium fluoride and optionally others, such as chromium nitrate.
- the organo-functional silane is preferably an aminopropyltriethoxy silane, and the compound of a group IV-B element is preferably fluorozirconic acid.
- the composition can either be dried-in-place or rinsed before a further coating layer is applied.
- the composition may also include at least one polymer having a plurality of both carboxylic functional groups, alone or with hydroxyl groups.
- the document also discloses a process using the aqueous composition either with or without the organo-functional silane along with a sealing step following the application of the aqueous composition; wherein the sealing step involves applying a sealing composition, including an organo-functional silane, to the metal surface.
- a process for surface treatment of a part made of aluminium, magnesium, or one of the alloys thereof, is known in order to protect the part from corrosion.
- the method comprises consecutively immersing the part in a first aqueous bath containing a corrosion-inhibiting metal salt such as trivalent chromium salt and an oxidizing compound such as K 2 ZrF 6 , and a second aqueous bath containing an oxidizing compound like hydrogen peroxide and a corrosion-inhibiting rare-earth salt.
- the method can be carried out for the chemical conversion of aluminium or the alloys thereof, and of magnesium or the alloys thereof, on parts that have not been previously treated, or after anodizing the part to seal the anodic layer.
- US 6648986 B1 teaches an acidic aqueous solution that contains a water soluble trivalent chromium compound, a water soluble fluoride compound, an alkaline pH adjustment reagent and provided with a solution stability additive for reducing precipitation of trivalent chromium over time.
- the solution stability additive comprises a complexing agent that is selected from the group consisting of organic acids (single coordination acids and bidentate chelating compounds) and amino acids.
- concentration of the solution stability additive varies based on the complexing capability of the additive.
- US 2010/0132843 A1 discloses a low sludge trivalent chromium based conversion coating bath that forms corrosion resistant coatings on aluminium and aluminium alloys by immersion in aqueous solutions containing trivalent chromium ions and fluorometallate ions followed by optional rinsing. Trivalent chromium coated aluminium also serves as an effective base for paint primers.
- US 2006/240191 A1 discloses a process for treating metal substrates to improve the corrosion protection and adhesion bonding strength which comprises treating the metal substrates with an acidic aqueous solution having a pH ranging from 1.0 to 5.5, wherein the acidic solution comprises a trivalent chromium compound, a fluorozirconate compound and at least one stabilizing agent compound selected from the group consisting of polyhydroxy compounds, carboxylic compounds and mixtures thereof.
- Another object is to provide such a stable treatment solution that offers an enhanced layer formation.
- a further object is to provide a method of applying a treatment composition to such a metal substrate in order to achieve corrosion resistance and/or adhesion.
- the invention provides an acidic aqueous composition for preparing a corrosion resistant layer on substrates of aluminium, aluminium alloys, anodized aluminium, zinc or zinc alloy coated steel, aluminized steel, wherein the composition comprises: trivalent chromium (Cr 3+ ): 0.04 - 6 g/l zirconium (Zr 4+ ): 0.08 - 8 g/l total fluoride (F - ): 0.1 - 9 g/l stabilizing agent comprising a hydroxyl carboxylic acid or corresponding bases thereof (calculated as the acid): 0.2 - 9 g/l wherein
- the aqueous composition according to the invention when used as a bath is stable in time and does not form deposits and/or sludge in the bath.
- the surface which is essentially free of Cr 6+ , shows good corrosion resistance and if present, durable bonding to a subsequently applied paint system or adhesive bonding system.
- the acidic aqueous composition according to the invention comprises as main active components trivalent chromium, tetravalent zirconium and fluoride in specific concentrations and ratios, as well as one or more hydroxyl carboxylic acids as stabilizing agent.
- Trivalent chromium is present in an amount of 0.04-6 g/l, preferably 0.2-1.0 g/l for dipping and spraying applications. For touch-up, maintenance and repair applications using e.g. brushing and wiping a broader range of 0.5-5.0 g/L is advantageous. If the amount of chromium (III) is lower, then within industrially acceptable processing times, the rate of layer formation is low resulting in a layer having an insufficient thickness and thus inadequate protection and/or bonding.
- the trivalent chromium can be derived from organic chromium salts, in particular citrate, glycolate, tartrate, and combinations thereof.
- Another attractive route for obtaining trivalent chromium is by reducing chromic acid (H 2 CrO 4 ) with chemical agents that can be oxidized by chromic acid like methanol or hydrogen peroxide leaving no residual products in the starting solution after heating.
- Another attractive source for trivalent chromium and fluoride is using OF 3 .4H 2 O as a starting material. This compound is hardly soluble in water, but accompanied by acidic components like HF, acidic hydroxyl carboxylic stabilizing agents and water soluble acidic polymers or combinations thereof, it is.
- HF is preferably used as it does not introduce extraneous anions other than those required.
- Tetravalent zirconium is present in an amount of 0.08-8 g/l, preferably in the range of 0.2-2.0 g/l.
- Suitable starting materials comprise hexafluozirconic acid and its ammonium salt, zirconium salts of lactate, carbonate, glycolate and citrate, ammonium zirconium carbonate and zirconium triethanol amine, and combinations thereof.
- the high zirconium content is believed to enhance co-precipitation of Cr and Zr as Cr(OH) 3 and Zr(OH) 4 and thereby layer formation.
- F- ions are present in the range of 0.1-9 g/l, preferably 0.2-2.0 g/l.
- the fluoride can be obtained from HF, alkali metal fluoride like sodium fluoride, ammonium bi fluoride (ABF), chromium fluoride, hexafluo zirconic acid and its ammonium salt, as well as combinations thereof. If hexafluo zirconic acid is used as a starting material, at least one other zirconium component is present, otherwise the ratio of Zr : F is not within the required range. High fluoride contents compared to Cr and Zr results in excessive etching hindering layer formation. Without being bound to any theory it is believed that fluoride contents in the solution according to the invention will prevent over-etching during layer formation and might prevent accumulation of fluorides in the layer that could weaken the conversion layer during exposure in corrosive environment.
- Low fluoride contents have the opposite effect and may reduce stability of the composition.
- the molar ratio Zr 4+ : Cr 3+ is in the range of 0.8 : 1 to 2.0 : 1; preferably 0.9:1 - 1.3 : 1, such as 1.04: 1.0; and the molar ratio Zr 4+ : F - is in the range of 1: 5.5 to 1.0 : 2.0.
- the acidic aqueous comprises a stabilizing agent being a hydroxy carboxylic acid or a corresponding base thereof in a concentration of 0.2-9 g/l, preferably in the range of 0.2- 5 g/l, more preferably 0.3 - 3 g/l (calculated as the acid).
- the stabilizing agent can be used as the acid or a water soluble salt thereof.
- Suitable hydroxyl carboxylic acids are lactic acid, citric acid, malic acid, tartaric acid, glycolic acid, gluconic acid and combinations thereof.
- the stabilizing agent may be introduced in the composition by the chromium or zirconium compound as well as shown above in the form of the zirconium and/or chromium (III) salt of the conjugated base of the hydroxy carboxylic acid, or as a similar part of the pH adjusting agents as discussed below.
- the stabilizing agent acts to stabilize the solution as a dipping bath having the composition according to the invention in time, which bath would otherwise at the given concentrations and ratios of its components deteriorate rapidly. It is assumed that the acid becomes part of the resulting layer comprising the hydroxides and oxides of chromium and zirconium. Higher contents of hydroxyl carboxylic acids results in coating layers that are sensitive to dissolving.
- the composition according to the invention has a pH in the range of 3.0-5.0, preferably 3.4-4.4. If the pH is too low then the formation of the protective layer on the substrate is limited by the simultaneous attack of the formed layer by the acidic components. Thus the composition as a whole offers a balance between components and the amount thereof, their functional properties and processing possibilities.
- the composition may contain pH adjusting agents, typically bases, such as one or more alkali metal hydroxides like sodium hydroxide, potassium hydroxide and ammonia.
- the pH adjusting agent may be a source of the base of the hydroxyl carboxylic acid stabilizing agent.
- examples include lactate, citrates of ammonium and/or sodium and the like.
- the pH adjusting agent is present in amount of 0-1.0 g/l.
- the alkali metal cations do not - or to a negligible extent - affect the formation of the protective layer.
- the pH rises to values above 5 the composition can easily become instable. At pH less than 3.0 it is hard to form substantial coating weight in view of corrosion resistance.
- the composition may also comprise one or more water soluble surfactants for improving the wetting properties, advantageously in a concentration of 0-1.0 g/l, preferably 0.001-0.5 g/l.
- surfactants that can be used in the composition according to the invention include acid stable low foaming anionic and non-ionic surfactants like alkaryl sulfonates and poly ethylene glycol fatty amines. The surfactant provides uniform wetting of the substrate. If the amount of surfactant is too high, it can cause excessive foaming in the process.
- compositions according to the invention comprise water soluble polymers and organo-functional silanes and/or their hydrolysed oligomers.
- the water soluble polymers include homopolymers and copolymers that preferably are based on the following monomers: acrylic acid, methacrylic acid, vinylalcohol, vinylether, maleic acid, monohydroxy acrylic ester, vinylphosphonic acid, vinylsulphonic acid, methyl vinylether, monohydroxy methacrylic ester and combinations thereof, up to 4.0 g/l, preferably 0.01-4.0 g/l, more preferably 0.1-1 g/l. These polymers improve wetting behaviour of the treatment composition, as well as adhesion of subsequently applied organic coatings. Too high concentrations will reduce wet adhesion of an organic coating.
- the concentration of the silanes or oligomers, if present, ranges up to 4.0 g/l.
- the reactive functional group is at least one selected from a mercapto group, an amino group, a vinyl group, an epoxy group and a methacryloxy group, advantageously in an amount of 1 to 40 mg/l based on Si.
- the invention relates to a method of treating a substrate of aluminium, aluminium alloy, anodized aluminium, aluminized steel, zinc or zinc alloy coated steel for corrosion protection, adhesion of an organic coating or adhesive bonding system, which method comprises a step of applying the acidic aqueous solution according to the invention as explained above onto a substrate of aluminium, aluminium alloy, anodized aluminium, aluminized steel, zinc or zinc alloy coated steel.
- the metal surface to be treated with the composition according to the invention is pre-treated using known mechanical and/or chemical pre-treatment processes or combination thereof for obtaining a wettable surface, which typically requires the surface to be roughened and to be substantially free of rust, fat, oil and the like.
- Mechanical pre-treatment processes comprise grit blasting, shot peening, scuffing, scotch brite® and abrading.
- Chemical pre-treatment includes e.g. (acidic/alkaline/solvent) degreasing, de-oxidation, desmutting, pickling.
- each chemical pre-treatment is followed by a rinsing step using tap water or demineralised water. Combinations of mechanical pre-treatment and chemical pre-treatment in any order is also possible.
- the surface may be anodized.
- treatment according to the invention of bare aluminium will form a conversion layer. Treating anodized aluminium according to the invention will result in a sealing layer.
- the way of applying the composition according to the invention to the metal surface is not limited. However, homogeneity and uniformity of the applied wet film on the substrate before drying will be advantageous. Suitable application methods include touch-up methods, spraying, dipping, wiping, brushing, roll coating and the like. Excess of treatment fluid on parts with intricate geometries can be removed with water rinsing, compressed air or wiping. After applying the acidic aqueous composition one or more rinsing steps with demi water are performed, preferably the last rinsing step with demi water having an electrical conductivity in the range of 5-200 microS, and a drying step of drying the thus rinsed substrate, in particular at a temperature in the range of 10-50 °C.
- the method according to the invention is performed with the composition having a temperature in the range of 10-80°C, preferably 15-50 °C.
- the processing time ranges from 1-30 minutes, preferably from 3-15 minutes. Processing times of less than 3 minutes are practically not feasible on industrial scale in view of reproducible coating results. Processing times of more than 30 minutes may interfere with other operations on a continuous production line.
- the coating weight as measured by XRF after drying, is typically in the range of 5-200 mg Cr/m 2 , such as 15-100 mg Cr/m 2 .
- coating weight can be controlled by adjusting concentration, pH, bath temperature and immersion time. Too high coating weights will give corrosion resistance, but may reduce adhesion properties and increase the surface electrical resistivity. Low electrical resistivity of the metal surface is important for certain applications as it prevents build-up of static electricity and will not influence welding properties.
- the method according to the invention is very suitable for maintenance and repair of damaged aluminium surfaces, like aerostructural parts, in particular where electrical resistivity of the resulting protective layer should be low, e.g. as detailed in MIL-DTL-5541F Class 3 coatings.
- This further treatment step comprises post-treating the substrate that has been treated with the acidic aqueous composition, with a second acidic aqueous composition comprising an oxidizing agent and an acidifying component, which second composition has a pH in the range of 1-5, preferably 1-3. It has been shown that the risk of formation of Cr 6+ in the formed protective layer is reduced by using the acidic second solution. Cr 6+ was less than the detection limit ( ⁇ 0.03 ⁇ g/cm 2 ) in the used second solution and in the thus obtained protective layer.
- the oxidizing component is a water soluble peroxide, preferably hydrogen peroxide.
- Hydrogen peroxide functions as a reductor with respect to Cr 6+ in an acidic environment.
- trivalent chromium will not be converted into hexavalent chromium.
- concentration of the oxidizing component ranges typically from 10-100 g/l, preferably from 25-100 g/l.
- the acidifying component is present in a concentration of 0.2-20 g/l, preferably 0.5-5.0 g/l.
- the acidifying component is advantageously a non-halogenated inorganic acid such as nitric acid, or a metal salt thereof excluding rare earth metals, preferably a salt of aluminium, zirconium and/or trivalent chromium, preferably the nitrate salt thereof.
- These acidic components should not dissolve the applied coating by the first composition nor etch aluminium.
- Nitric acid is a strong acid but has shown not to attack the coating from the first solution. Other strong acids like hydrogen chloride and sulphuric acid are too aggressive towards the first deposited layer.
- the second composition should be acidic enough to avoid formation of hexavalent chromium.
- the temperature of the second composition is preferably in the range of 10-50 °C, more preferably at ambient temperature, like 20-30 °C. Such a low temperature is advantageous in order to avoid fast decomposition of peroxides.
- Treating time is typically 1-30 minutes, preferably 3-15 minutes.
- Suitable application methods for the second composition include spraying, dipping, wiping, brushing, roll coating and the like.
- the invention is illustrated by the following Examples and Tests.
- Composition 1 and 2 as indicated in Table 1 were prepared from commercially available compounds, as well as a Comparative Example without any hydroxy carboxylic acid. It appears that the composition of the Comparative Example is not stable. Table 1. Examples starting Compositions according to the invention and Comparative Example and their stability Composition 1 (wt.%) Composition 2 (wt.%) Comparative Example (wt.%) Zirconium triethanolamine (13.8 wt.% Zr) 4 Hexafluoro zirconium acid (19.8 wt.% Zr) 1.41 Ammonium zirconium carbonate (14.8 wt.%Zr) 4.5 4.5 Chromium trifluoride *4 H 2 O (28,7 wt.% Cr) 1.51 1,03 1.03 Hydrogen fluoride (20%) 0.9 0.9 Malic acid (99%) 0.9 0.7 Remainder water Zr : Cr mol ratio 1.1 : 1 1.3 : 1 1.3:1 Zr : F mol ratio 1 : 4.8 1 : 3.6 1:3.6 St
- Table 4 shows the various (optional) method steps and the conditions thereof, which are carried out according to the invention.
- Table 4. General process conditions, preferred conditions and actual test values.
- Product Concentration [wt.%] Treatment time [min] Temp. [°C] pH Alkaline degreasing (Cleaner ABF) 3.0 3-7 (5) 50-55 (53) 9-10 (9.5) Tap water rinsing Acidic deoxidation/ desmutting (Adeox 11) 3.5 3-7 (5) 15-25 (20) 1-3 (1) Tap water rinsing Demi water rinsing First treatment solution (C2) 5-20 2-20 [5--15] (10) 10--80 [30 - 45] (40) 3-5 [3.4- 4.4] (3.9) Demi water rinsing Forced hot air drying (optionally) 10-- 80 [40 --60] Second treatment solution (P1) 0 -60 [3--7] (5) 5--60 [15-- 30] (20) 1-5 [1-3] (2.5) Demi water rin
- Alodine 1200S treated samples the aluminium substrate panels were subjected to the steps as summarized in below Table 5. Table 5.
- Pre-treatment and treatment steps for Alodine 1200 treated samples Product Immersion time [min] Temperature [°C] Alkaline Predegreasing Turco 6849 10 60 Alkaline degreasing Turco 4215 10 65 Tap water rinsing Acidic deoxidation/desmutting Socosurf 1858 5 45 Tap water rinsing Demi water rinsing Conversion Coating Alodine 1200S 2 RT Demi water rinsing
- Table 7 shows data of the resulting layer weight of a conversion coating applied to AA2024 steel using 8 wt% solution of composition 2 (C2) under varying process time, using varying immersion (dipping) times, pH and T conditions.
- Tthe aluminium was pre-treated as listed in Table 4.
- AA2024-T3 panels were treated with first treatment solution C1 under the same conditions as listed in Table 4 for C2 and various second treatment solutions.
- Table 8 shows the corrosion test results of 2024 aluminium alloy, as well as the Cr 6+ content present in conversion coating determined by boiling water extraction.
- Table 9 Coating weight [mg Cr/m 2 ] contact resistance MIL-DTL-81706 B Class 3 conversion coating ⁇ 5 m ⁇ /in2) [m ⁇ /in2] corrosion resistance MIL-DTL-5541F ASTM-B117 >168 hrs [hrs] AA2024-T3 23 0.4 >168 AA2024-T81 15 0.5 >168 AA6061-T6 30 1.6 >3000 AA7075-T73 30 1.5 >168 AA5083-H111 41 2.3 >168
- the method and compositions according to the invention are also suitable for maintenance and repair purposes, such as maintenance of aeroplanes, using the so-called touch-up or brush (wipe) methods, wherein the respective Al parts are degreased and any oxide skin is removed mechanically. Thereafter the first and second treatment solutions according to the invention are applied using a double (vertical and horizontal) wipe technique with dust free cloth.
- Table 11 presents further corrosion results of various metal substrates when treated according to the invention with C2 and optionally P1.
- Table 11. Overview corrosion test results various aluminium alloys treated with C2, optionally followed by post-rinse P1 at room temperature during 5 minutes.
Description
- The invention relates to an acidic aqueous composition for preparing a corrosion resistant coating on a metal substrate, a method of providing a corrosion resistant coating on a metal substrate, as well as a post-treatment composition, in particular for use in said method.
- In the art mechanical and chemical treatment of metal surfaces for enhancing (bare) corrosion resistance, as well as for improving bonding to a subsequently applied coating such as an adhesive layer, paint layer, lacquer layer or other finishing layer and thereby enhancing the corrosion resistance of the thus coated final product is well known. E.g. mechanical treatment such as grit blasting has been used to improve adhesion, when chemical treatment steps were not practical to apply. Chemical treatment of metal surfaces of zinc (alloy) coated steel, mild steel, or aluminium and their alloys with aqueous chromate (chromium VI) solutions results in a so called "chromate conversion layer", which offers corrosion resistance and improved adhesion.
- It has been recognized that these chromate based aqueous solutions suffer from the toxicity of the Cr6+ component thereof. Cr6+ is classified as carcinogenic and will be banned from most industrial applications involving high exposure risks for the operating staff. Disposal of the toxic treatment composition is also a problem, although to a lesser extent if the hexavalent chromium is converted into the comparatively innocuous trivalent chromium. However, such a conversion brings about additional costs and expenses.
- Therefore, in the art there is a need for treatments that are substantially free of hexavalent chromium compounds, that offer corrosion resistance and bonding performance to the metal surfaces treated similar to those obtained by treating these metal surfaces with conventional solutions comprising hexavalent chromium. Proposals for satisfying this need, which are based on Cr(III) typically in combination with one or more other active components such as zirconium, are known.
- From
US 2011/0293841 A1 an aqueous solution for forming a protective coating on a metal surface is known that includes Cr2(GF6), in which G is a Group IV-B element (Zr, Ti or Hf), in particular Cr2(ZrF6)3 at least one polymer having a plurality of carboxylic acid groups such as polyacrylic acid and copolymers of methyl vinyl ether and maleic acid, and at least one polymer having a plurality of hydroxyl groups for example polyvinyl alcohols and homopolymers or copolymers of hydroxyethyl methacrylate, and/or at least one polymer having a plurality of both carboxylic acid and hydroxyl acid groups exemplified by free-radical copolymers of hydroxyl-ethyl methacrylate and methacrylic acid, wherein the composition contains less than 500 ppm of alkali metal ions and less than 200 ppm of halide ions relative to chromium. Application of a high purity Cr2(ZrF6)3 solution, is said to improve the corrosion resistance of the metal substrate. The Zr : Cr molar ratio is typically determined by the stoichiometry of the compound, but due to the optional presence of other components the weight ratio Zr : Cr is typically in the range of 2.4 : 1 - 3.0 : 1, most typically 2.6:1 -2.8:1. Any metal may be treated, with apparently good results being obtained on zinc, zinc alloy, aluminium and aluminium alloy surfaces. The addition of organo-functional silanes such as aminoproyl triethoxysilane may improve adhesion of subsequently applied coatings such as paints) to the treated surfaces, while maintaining good corrosion results. For a working bath the pH of a treatment solution comprising the above polymers is in a range from 2.5 - 4.0, more typically 2.8-3.2. -
US 6375726 B1 has disclosed an acidic aqueous solution for the protection and surface treatment of aluminium, aluminium alloys and coated aluminium substrates against corrosion. The solution comprises at least one trivalent chromium salt such as trivalent chromium sulphate, at least one alkali metal hexafluorozirconate in combination with at least one water soluble or dispersible thickening agent and a water soluble surfactant. The corrosion resistant aluminium substrates of this invention have improved adhesion for overlaying coatings e.g. paints and a lower electrical resistance contact. -
WO 2006/088519 A2 discloses an acidic aqueous solution for treating metal substrates, such as aluminium alloy or iron alloy or a metal substrate having a pre-existing metal coating for example anodized aluminium to improve the adhesion bonding and corrosion protection, which comprises water soluble trivalent chromium compounds, fluorozirconates, fluorometallic compounds, zinc compounds, thickeners, surfactants, and at least about 0.001 mole per litre of the acidic solution of at least one polyhydroxy and/or carboxylic compound as the stabilizing agent for the aqueous solution. The carboxylic compounds contain one or more carboxylic functional groups having the formula R-COO- wherein R is hydrogen or a lower molecular weight organic radical or functional group, and can be used in the form of their acids or salts. The stabilizers are said to result in improved shelf-life and working stability of the solutions. According to this document after treating with the acid aqueous solution, application of a strong oxidizing solution can yield a film having additional corrosion resistance, which is presumed to be due to the formation of hexavalent chromium in the film derived from the trivalent chromium. - Furthermore an acidic, aqueous composition that contains a trivalent chromium compound, an organo-functional silane, and a compound of a group IV-B element, is known from
US 2009/0280253 A1 . The composition is said to protect metal surfaces, preferably aluminium and aluminium alloys, against corrosion and improves their paint adhesion. The trivalent chromium compound may comprise chromium fluoride and optionally others, such as chromium nitrate. The organo-functional silane is preferably an aminopropyltriethoxy silane, and the compound of a group IV-B element is preferably fluorozirconic acid. The composition can either be dried-in-place or rinsed before a further coating layer is applied. The composition may also include at least one polymer having a plurality of both carboxylic functional groups, alone or with hydroxyl groups. The document also discloses a process using the aqueous composition either with or without the organo-functional silane along with a sealing step following the application of the aqueous composition; wherein the sealing step involves applying a sealing composition, including an organo-functional silane, to the metal surface. - From
US 2015/0020925 A1 a process for surface treatment of a part made of aluminium, magnesium, or one of the alloys thereof, is known in order to protect the part from corrosion. The method comprises consecutively immersing the part in a first aqueous bath containing a corrosion-inhibiting metal salt such as trivalent chromium salt and an oxidizing compound such as K2ZrF6, and a second aqueous bath containing an oxidizing compound like hydrogen peroxide and a corrosion-inhibiting rare-earth salt. The method can be carried out for the chemical conversion of aluminium or the alloys thereof, and of magnesium or the alloys thereof, on parts that have not been previously treated, or after anodizing the part to seal the anodic layer. -
US 6648986 B1 teaches an acidic aqueous solution that contains a water soluble trivalent chromium compound, a water soluble fluoride compound, an alkaline pH adjustment reagent and provided with a solution stability additive for reducing precipitation of trivalent chromium over time. The solution stability additive comprises a complexing agent that is selected from the group consisting of organic acids (single coordination acids and bidentate chelating compounds) and amino acids. The concentration of the solution stability additive varies based on the complexing capability of the additive. -
US 2010/0132843 A1 discloses a low sludge trivalent chromium based conversion coating bath that forms corrosion resistant coatings on aluminium and aluminium alloys by immersion in aqueous solutions containing trivalent chromium ions and fluorometallate ions followed by optional rinsing. Trivalent chromium coated aluminium also serves as an effective base for paint primers. -
US 2006/240191 A1 discloses a process for treating metal substrates to improve the corrosion protection and adhesion bonding strength which comprises treating the metal substrates with an acidic aqueous solution having a pH ranging from 1.0 to 5.5, wherein the acidic solution comprises a trivalent chromium compound, a fluorozirconate compound and at least one stabilizing agent compound selected from the group consisting of polyhydroxy compounds, carboxylic compounds and mixtures thereof. - It is an object of the invention to provide a stable treatment solution based on Cr(III) for a substrate of aluminium, aluminium alloys, anodized aluminium, aluminized steel, zinc or zinc alloy coated steel with a layer, that protects the substrate against corrosion and/or offers adhesion for a subsequently applied (typically organic) coating such as paint, and/or for adhesive bonding system, or at least an alternative treatment solution.
- Another object is to provide such a stable treatment solution that offers an enhanced layer formation.
- A further object is to provide a method of applying a treatment composition to such a metal substrate in order to achieve corrosion resistance and/or adhesion.
- Another object is to provide such a method that does not result in Cr6+ species in the deposited layer that are easily released from the treated product under severe conditions. Yet another object is to provide such a method that is easy to apply in maintenance and repair of aerostructural parts.
- According to a first aspect the invention provides an acidic aqueous composition for preparing a corrosion resistant layer on substrates of aluminium, aluminium alloys, anodized aluminium, zinc or zinc alloy coated steel, aluminized steel, wherein the composition comprises:
trivalent chromium (Cr3+): 0.04 - 6 g/l zirconium (Zr4+): 0.08 - 8 g/l total fluoride (F-): 0.1 - 9 g/l stabilizing agent comprising a hydroxyl carboxylic acid or corresponding bases thereof (calculated as the acid): 0.2 - 9 g/l - the molar ratio Zr4+ : Cr3+ is in the range of 0.8 : 1 to 2.0 : 1;
- the molar ratio Zr4+ : F- is in the range of 1: 5.5 to 1.0 : 2.0; and
- pH is in the range of 3.0 - 5.0.
- It has been shown that the aqueous composition according to the invention when used as a bath is stable in time and does not form deposits and/or sludge in the bath. When applied to a surface of aluminium, aluminium alloys and anodized aluminium, zinc or zinc alloy coated steel, the surface, which is essentially free of Cr6+, shows good corrosion resistance and if present, durable bonding to a subsequently applied paint system or adhesive bonding system.
- The acidic aqueous composition according to the invention comprises as main active components trivalent chromium, tetravalent zirconium and fluoride in specific concentrations and ratios, as well as one or more hydroxyl carboxylic acids as stabilizing agent. Thereby a stable solution is provided with less fluoride with respect hexafluozirconic acid (H2ZrF6) or ((alkali) metal) salt thereof, wherein the ratio Zr : F = 1 : 6.
- Trivalent chromium is present in an amount of 0.04-6 g/l, preferably 0.2-1.0 g/l for dipping and spraying applications. For touch-up, maintenance and repair applications using e.g. brushing and wiping a broader range of 0.5-5.0 g/L is advantageous. If the amount of chromium (III) is lower, then within industrially acceptable processing times, the rate of layer formation is low resulting in a layer having an insufficient thickness and thus inadequate protection and/or bonding.
- The trivalent chromium can be derived from organic chromium salts, in particular citrate, glycolate, tartrate, and combinations thereof. Another attractive route for obtaining trivalent chromium is by reducing chromic acid (H2CrO4) with chemical agents that can be oxidized by chromic acid like methanol or hydrogen peroxide leaving no residual products in the starting solution after heating. Another attractive source for trivalent chromium and fluoride is using OF3.4H2O as a starting material. This compound is hardly soluble in water, but accompanied by acidic components like HF, acidic hydroxyl carboxylic stabilizing agents and water soluble acidic polymers or combinations thereof, it is. HF is preferably used as it does not introduce extraneous anions other than those required.
- Tetravalent zirconium is present in an amount of 0.08-8 g/l, preferably in the range of 0.2-2.0 g/l. Suitable starting materials comprise hexafluozirconic acid and its ammonium salt, zirconium salts of lactate, carbonate, glycolate and citrate, ammonium zirconium carbonate and zirconium triethanol amine, and combinations thereof. The high zirconium content is believed to enhance co-precipitation of Cr and Zr as Cr(OH)3 and Zr(OH)4 and thereby layer formation.
- F- ions are present in the range of 0.1-9 g/l, preferably 0.2-2.0 g/l. The fluoride can be obtained from HF, alkali metal fluoride like sodium fluoride, ammonium bi fluoride (ABF), chromium fluoride, hexafluo zirconic acid and its ammonium salt, as well as combinations thereof. If hexafluo zirconic acid is used as a starting material, at least one other zirconium component is present, otherwise the ratio of Zr : F is not within the required range. High fluoride contents compared to Cr and Zr results in excessive etching hindering layer formation. Without being bound to any theory it is believed that fluoride contents in the solution according to the invention will prevent over-etching during layer formation and might prevent accumulation of fluorides in the layer that could weaken the conversion layer during exposure in corrosive environment.
- Low fluoride contents have the opposite effect and may reduce stability of the composition.
- In addition to the concentration ranges the following molar ratio apply.
- The molar ratio Zr4+ : Cr3+ is in the range of 0.8 : 1 to 2.0 : 1; preferably 0.9:1 - 1.3 : 1, such as 1.04: 1.0;
and
the molar ratio Zr4+ : F- is in the range of 1: 5.5 to 1.0 : 2.0. - Then the molar ratio Cr3+ : F- is in the range of 1 : 11 to 1 : 1.6.
- The acidic aqueous comprises a stabilizing agent being a hydroxy carboxylic acid or a corresponding base thereof in a concentration of 0.2-9 g/l, preferably in the range of 0.2- 5 g/l, more preferably 0.3 - 3 g/l (calculated as the acid). The stabilizing agent can be used as the acid or a water soluble salt thereof. Suitable hydroxyl carboxylic acids are lactic acid, citric acid, malic acid, tartaric acid, glycolic acid, gluconic acid and combinations thereof. The stabilizing agent may be introduced in the composition by the chromium or zirconium compound as well as shown above in the form of the zirconium and/or chromium (III) salt of the conjugated base of the hydroxy carboxylic acid, or as a similar part of the pH adjusting agents as discussed below. The stabilizing agent acts to stabilize the solution as a dipping bath having the composition according to the invention in time, which bath would otherwise at the given concentrations and ratios of its components deteriorate rapidly. It is assumed that the acid becomes part of the resulting layer comprising the hydroxides and oxides of chromium and zirconium. Higher contents of hydroxyl carboxylic acids results in coating layers that are sensitive to dissolving. Too low contents will cause instability and sludge forming of the composition during operation, typically a process bath for dipping, over time. The composition according to the invention has a pH in the range of 3.0-5.0, preferably 3.4-4.4. If the pH is too low then the formation of the protective layer on the substrate is limited by the simultaneous attack of the formed layer by the acidic components. Thus the composition as a whole offers a balance between components and the amount thereof, their functional properties and processing possibilities. In order to set the acidity at the required level the composition may contain pH adjusting agents, typically bases, such as one or more alkali metal hydroxides like sodium hydroxide, potassium hydroxide and ammonia. As said before, the pH adjusting agent may be a source of the base of the hydroxyl carboxylic acid stabilizing agent. Examples include lactate, citrates of ammonium and/or sodium and the like. Advantageously the pH adjusting agent is present in amount of 0-1.0 g/l. The alkali metal cations do not - or to a negligible extent - affect the formation of the protective layer. When the pH rises to values above 5, the composition can easily become instable. At pH less than 3.0 it is hard to form substantial coating weight in view of corrosion resistance.
- The composition may also comprise one or more water soluble surfactants for improving the wetting properties, advantageously in a concentration of 0-1.0 g/l, preferably 0.001-0.5 g/l. Surfactants that can be used in the composition according to the invention include acid stable low foaming anionic and non-ionic surfactants like alkaryl sulfonates and poly ethylene glycol fatty amines. The surfactant provides uniform wetting of the substrate. If the amount of surfactant is too high, it can cause excessive foaming in the process.
- Other optional components of the composition according to the invention comprise water soluble polymers and organo-functional silanes and/or their hydrolysed oligomers. The water soluble polymers include homopolymers and copolymers that preferably are based on the following monomers: acrylic acid, methacrylic acid, vinylalcohol, vinylether, maleic acid, monohydroxy acrylic ester, vinylphosphonic acid, vinylsulphonic acid, methyl vinylether, monohydroxy methacrylic ester and combinations thereof, up to 4.0 g/l, preferably 0.01-4.0 g/l, more preferably 0.1-1 g/l. These polymers improve wetting behaviour of the treatment composition, as well as adhesion of subsequently applied organic coatings. Too high concentrations will reduce wet adhesion of an organic coating. The concentration of the silanes or oligomers, if present, ranges up to 4.0 g/l. Advantageously the reactive functional group is at least one selected from a mercapto group, an amino group, a vinyl group, an epoxy group and a methacryloxy group, advantageously in an amount of 1 to 40 mg/l based on Si.
- According to a second aspect the invention relates to a method of treating a substrate of aluminium, aluminium alloy, anodized aluminium, aluminized steel, zinc or zinc alloy coated steel for corrosion protection, adhesion of an organic coating or adhesive bonding system, which method comprises a step of applying the acidic aqueous solution according to the invention as explained above onto a substrate of aluminium, aluminium alloy, anodized aluminium, aluminized steel, zinc or zinc alloy coated steel.
- Typically the metal surface to be treated with the composition according to the invention is pre-treated using known mechanical and/or chemical pre-treatment processes or combination thereof for obtaining a wettable surface, which typically requires the surface to be roughened and to be substantially free of rust, fat, oil and the like. Mechanical pre-treatment processes comprise grit blasting, shot peening, scuffing, scotch brite® and abrading. Chemical pre-treatment includes e.g. (acidic/alkaline/solvent) degreasing, de-oxidation, desmutting, pickling. Typically each chemical pre-treatment is followed by a rinsing step using tap water or demineralised water. Combinations of mechanical pre-treatment and chemical pre-treatment in any order is also possible. In case of aluminium or its alloys the surface may be anodized. Typically treatment according to the invention of bare aluminium will form a conversion layer. Treating anodized aluminium according to the invention will result in a sealing layer.
- The way of applying the composition according to the invention to the metal surface is not limited. However, homogeneity and uniformity of the applied wet film on the substrate before drying will be advantageous. Suitable application methods include touch-up methods, spraying, dipping, wiping, brushing, roll coating and the like. Excess of treatment fluid on parts with intricate geometries can be removed with water rinsing, compressed air or wiping. After applying the acidic aqueous composition one or more rinsing steps with demi water are performed, preferably the last rinsing step with demi water having an electrical conductivity in the range of 5-200 microS, and a drying step of drying the thus rinsed substrate, in particular at a temperature in the range of 10-50 °C.
- Advantageously the method according to the invention is performed with the composition having a temperature in the range of 10-80°C, preferably 15-50 °C. Typically the processing time ranges from 1-30 minutes, preferably from 3-15 minutes. Processing times of less than 3 minutes are practically not feasible on industrial scale in view of reproducible coating results. Processing times of more than 30 minutes may interfere with other operations on a continuous production line.
- The coating weight, as measured by XRF after drying, is typically in the range of 5-200 mg Cr/m2, such as 15-100 mg Cr/m2. For a composition according to this invention coating weight can be controlled by adjusting concentration, pH, bath temperature and immersion time. Too high coating weights will give corrosion resistance, but may reduce adhesion properties and increase the surface electrical resistivity. Low electrical resistivity of the metal surface is important for certain applications as it prevents build-up of static electricity and will not influence welding properties.
- It has appeared also that the method according to the invention is very suitable for maintenance and repair of damaged aluminium surfaces, like aerostructural parts, in particular where electrical resistivity of the resulting protective layer should be low, e.g. as detailed in MIL-DTL-5541F Class 3 coatings.
- For certain alloys, in particular those copper containing aluminium alloys as used in the aerospace technical field such as 2024 and 7075, it has appeared advantageously to conduct a further treatment step. This further treatment step comprises post-treating the substrate that has been treated with the acidic aqueous composition, with a second acidic aqueous composition comprising an oxidizing agent and an acidifying component, which second composition has a pH in the range of 1-5, preferably 1-3. It has been shown that the risk of formation of Cr6+ in the formed protective layer is reduced by using the acidic second solution. Cr6+ was less than the detection limit (<0.03 µg/cm2) in the used second solution and in the thus obtained protective layer.
- Advantageously the oxidizing component is a water soluble peroxide, preferably hydrogen peroxide. Hydrogen peroxide functions as a reductor with respect to Cr6+ in an acidic environment. Thus trivalent chromium will not be converted into hexavalent chromium. The concentration of the oxidizing component ranges typically from 10-100 g/l, preferably from 25-100 g/l.
- The acidifying component is present in a concentration of 0.2-20 g/l, preferably 0.5-5.0 g/l. The acidifying component is advantageously a non-halogenated inorganic acid such as nitric acid, or a metal salt thereof excluding rare earth metals, preferably a salt of aluminium, zirconium and/or trivalent chromium, preferably the nitrate salt thereof. These acidic components should not dissolve the applied coating by the first composition nor etch aluminium. Nitric acid is a strong acid but has shown not to attack the coating from the first solution. Other strong acids like hydrogen chloride and sulphuric acid are too aggressive towards the first deposited layer. The second composition should be acidic enough to avoid formation of hexavalent chromium.
- The temperature of the second composition is preferably in the range of 10-50 °C, more preferably at ambient temperature, like 20-30 °C. Such a low temperature is advantageous in order to avoid fast decomposition of peroxides.
- Treating time is typically 1-30 minutes, preferably 3-15 minutes.
- Suitable application methods for the second composition include spraying, dipping, wiping, brushing, roll coating and the like.
- The invention is illustrated by the following Examples and Tests.
- Composition 1 and 2 as indicated in Table 1 were prepared from commercially available compounds, as well as a Comparative Example without any hydroxy carboxylic acid. It appears that the composition of the Comparative Example is not stable.
Table 1. Examples starting Compositions according to the invention and Comparative Example and their stability Composition 1 (wt.%) Composition 2 (wt.%) Comparative Example (wt.%) Zirconium triethanolamine (13.8 wt.% Zr) 4 Hexafluoro zirconium acid (19.8 wt.% Zr) 1.41 Ammonium zirconium carbonate (14.8 wt.%Zr) 4.5 4.5 Chromium trifluoride *4 H2O (28,7 wt.% Cr) 1.51 1,03 1.03 Hydrogen fluoride (20%) 0.9 0.9 Malic acid (99%) 0.9 0.7 Remainder water Zr : Cr mol ratio 1.1 : 1 1.3 : 1 1.3:1 Zr : F mol ratio 1 : 4.8 1 : 3.6 1:3.6 Stability (no suspension or gel formed) > 240 days > 240 days < 1 day - From these starting Compositions first treatment solutions were prepared by dilution with demi water as indicated in Table 2. Table 3 lists compositions of the second treatment solutions.
Table 2 First treatment solutions (treatment 1 = TR1) Examples TR1 [Zr] g/L [Cr] g/L [F] g/L pH C1 20 wt.% of Composition 1 1.66 0.87 1.65 3.9 C2 8 wt.% of Composition 2 0.53 0.24 0.4 3.9 C3 65 wt.% of Compositon 2 4,31 1,95 3.2 3.6 Table 3 Second treatment solutions (treatment 2 =TR2) Examples TR 2 composition pH P1 Al(NO3)3 *9H2O, 4.33 g/l + H2O2 (30%) 50 g/l 2.5 P2 Sulphuric Acid (1M ) 5.33 g/L H2O2 (30%) 50 g/l 2.1 P3 HNO3 (1M) 34.63 g/L H2O2 (30%) 50 g/l 1.9 - Below Table 4 shows the various (optional) method steps and the conditions thereof, which are carried out according to the invention.
Table 4. General process conditions, preferred conditions and actual test values. Product Concentration [wt.%] Treatment time [min] Temp. [°C] pH Alkaline degreasing (Cleaner ABF) 3.0 3-7 (5) 50-55 (53) 9-10 (9.5) Tap water rinsing Acidic deoxidation/ desmutting (Adeox 11) 3.5 3-7 (5) 15-25 (20) 1-3 (1) Tap water rinsing Demi water rinsing First treatment solution (C2) 5-20 2-20 [5--15] (10) 10--80 [30 - 45] (40) 3-5 [3.4- 4.4] (3.9) Demi water rinsing Forced hot air drying (optionally) 10-- 80 [40 --60] Second treatment solution (P1) 0 -60 [3--7] (5) 5--60 [15-- 30] (20) 1-5 [1-3] (2.5) Demi water rinsing Forced hot air drying (optionally) (10) 10-- 80 [40 -- 60] (60) [..] represent preferred ranges; (..) actual test value in below Example 2. - In this test set-up panels of aluminium alloys AA2024-T3 and AA2024-T81 were treated according to the steps in table 4 and actual values listed therein for C2. Neutral salt spray resistance according ASTM B117 was compared on the same alloy with the most common used hexavalent chrome conversion coating Alodine 1200S.
- For the Alodine 1200S treated samples the aluminium substrate panels were subjected to the steps as summarized in below Table 5.
Table 5. Pre-treatment and treatment steps for Alodine 1200 treated samples Product Immersion time [min] Temperature [°C] Alkaline Predegreasing Turco 6849 10 60 Alkaline degreasing Turco 4215 10 65 Tap water rinsing Acidic deoxidation/desmutting Socosurf 1858 5 45 Tap water rinsing Demi water rinsing Conversion Coating Alodine 1200S 2 RT Demi water rinsing - Per conversion coating, 5 panels were treated and subjected to the neutral salt spray test described in ASTM B117. After 168 hours of exposure the panels were evaluated according to MIL-DTL-81706. The test results are summarized in below Table 6.
Table 6. Test results Al substrate Pit count after 168 hrs NSS Alodine 1200S C2/P1 1 AA2024-T3 3 5 0 3 2 3 1 3 1 2 2 AA2024-T81 7 5+ 6 5+ 5 3 6 3 6 3 - Corrosion resistance according to MIL-DTL-81706 requirements:
- (a) No more than 5 isolated spots or pits, none larger than 787 µm (0.031 in) diameter, per test specimen.
- (b) No more than 15 isolated spots or pits, none larger than 787 µm (0.031 in) in diameter, on the combined surface area of five test specimens, subjected to salt spray testing.
- Table 7 shows data of the resulting layer weight of a conversion coating applied to AA2024 steel using 8 wt% solution of composition 2 (C2) under varying process time, using varying immersion (dipping) times, pH and T conditions.
- Tthe aluminium was pre-treated as listed in Table 4.
Table 7 Effect of varying process conditions on the resulting layer weight of the conversion coating on AA2024 (expressed in mg Cr/m2) using 8 wt.% of composition 2 pH=4.2; T= 40°C Immersion t [min] 2 5 10 Coating weight {mg Cr/m2} 12.5 18.8 24.1 pH=4.2; t= 5 min. Temperature bath 1 [°} 30 35 40 Coating weight {mg Cr/m2} 13.7 16.3 18.8 t= 5 min; T=40°C pH bath 1 3.8 4 4.2 Coating weight {mg Cr/m2} 11.6 13.3 18.8 - AA2024-T3 panels were treated with first treatment solution C1 under the same conditions as listed in Table 4 for C2 and various second treatment solutions.
- Below Table 8 shows the corrosion test results of 2024 aluminium alloy, as well as the Cr 6+ content present in conversion coating determined by boiling water extraction.
Table 8. Aluminium alloy 2024 treated by C1 at 40 °C during 10 minutes, followed by a post rinse using various second treatment solutions. Second treatment solution Corrosion rating Salt Spray Test ASTM B117 after 168 hours Hexavalent chromium measured after boiling water extraction None >5 pits P1 2 pits < 0.03 µg/cm2 P2 2 pits < 0.03 µg/cm2 H2O2 (30%) 50 g/l 1 pits 0.09 µg/cm2 P3 3 pits < 0.03 µg/cm2 - From the test data it appears that the corrosion resistance of an AA2024-T3 substrate that is treated with a (trivalent chromium) first treatment solution according to the invention and a (hydrogen peroxide) second treatment solution according to the invention is improved compared to that of the same Al substrate that is only treated with the first treatment solution. Moreover the test data indicate that less hexavalent chromium is formed on the substrate due to the acidic, but non-aggressive nature of the second treatment solution.
- Different Al alloys were treated according to actual conditions listed in Table 4. The below Table 9 lists the test results.
Table 9 Coating weight [mg Cr/m2] contact resistance MIL-DTL-81706 B Class 3 conversion coating < 5 mΩ/in2) [mΩ/in2] corrosion resistance MIL-DTL-5541F ASTM-B117 >168 hrs [hrs] AA2024-T3 23 0.4 >168 AA2024-T81 15 0.5 >168 AA6061-T6 30 1.6 >3000 AA7075-T73 30 1.5 >168 AA5083-H111 41 2.3 >168 - The method and compositions according to the invention are also suitable for maintenance and repair purposes, such as maintenance of aeroplanes, using the so-called touch-up or brush (wipe) methods, wherein the respective Al parts are degreased and any oxide skin is removed mechanically. Thereafter the first and second treatment solutions according to the invention are applied using a double (vertical and horizontal) wipe technique with dust free cloth.
- Various Al alloys were subjected to an acidic etching with Adeox 8 (100 g/L), rinsed with water and then treated with first treatment solution C3 and again rinsed. For AA2024-T3 thereafter second treatment solution P3 was applied, followed by a rinsing step with water. Electrical resistivity and general corrosion performance were tested as shown in below Table 10.
Table 10 Alloy contact resistance MIL-DTL-81706 B Class 3 conversion coating Corrosion resistance (asis < 5 mΩ /in2) 168 hrs Salt Spray ASTM B117 (< 10 mΩ/in2) 336 hrs Salt Spray ASTM B117 [mΩ/ in2] [mΩ / in2] [pass/fail] AA2014-T3 0.2 2.1 pass AA5754 0.1 1.7 pass AA6061-T6 0.1 0.5 pass AA7075-T73 0.4 0.4 pass - Table 11 presents further corrosion results of various metal substrates when treated according to the invention with C2 and optionally P1.
Table 11. Overview corrosion test results various aluminium alloys treated with C2, optionally followed by post-rinse P1 at room temperature during 5 minutes. Aluminium Alloy C2 P1 Neutral Salt Spray < 5 pits ASTM B117 AA2024-T3 no no < 8 hr AA2024-T3 yes no >168 hr AA2024-T3 yes yes >500 hr AA5005 yes no >1000 hr AA5754 yes no >1000 hr AA6060 yes no >1000 hr AA6061-T6 yes no >1500 hr AA6061-T6 yes yes >3000 hr AA6063 yes no >1000 hr -
Table 12. Standard boric acid/sulphuric acid anodizing procedure on 2024 aluminium alloy 2024. Anodized coating thickness 5 µm. Anodized layer is treated /sealed with Composition 2 at 2 different concentrations (T=40 °C, t= 10 minutes) without post rinse. Example Immersion time [min] Bath temperature [°C] Conc. Cr3+ [g/L] Sealed according to this invention Measured Cr Corrosion rating Salt Spray Test ASTM B117 1 - - - - completely corroded in 24 h 2 10 40 0,5 80 Cr mg/m2 no pits after 168 h 3 10 40 0,25 40 Cr mg/m2 3 pits after 168 h -
Table 13. HDG (hot dip galvanized) Steel experiment Substrate fresh hot dipped galvanized steel cooled down to 80 °C Corrosion test Humidity 100% RH, 40°C Time to 5% white rust formation Corrosion test: ASTM B117 Neutral salt spray test Time to 5% white rust formation No treatment < 12 hours < 2 hours 10 wt.% Composition 2, Room Temperature, 10 minutes 500 hours 48 hours
Claims (15)
- An acidic aqueous composition for preparing a corrosion resistant layer on substrates of aluminium, aluminium alloys, anodized aluminium, zinc or zinc alloy coated steel, or aluminized steel, wherein the composition comprises:
trivalent chromium (Cr3+): 0.04 - 6 g/l zirconium (Zr4+): 0.08 - 8 g/l total fluoride (F-): 0.1 - 9 g/l stabilizing agent comprising a hydroxyl carboxylic acid or corresponding base(s) thereof (calculated as the acid): 0.2 - 9 g/l the molar ratio Zr4+ : Cr3+ is in the range of 0.8 : 1 to 2.0 : 1;the molar ratio Zr4+ : F- is in the range of 1: 5.5 to 1.0 : 2.0; andpH is in the range of 3.0 - 5.0. - The composition according to claim 1, wherein the concentration of trivalent chromium (Cr3+) is in the range of 0.2-1.0 g/L or in the range of 0.5-5.0 g/L.
- The composition according to claim 1 or 2, wherein the concentration of zirconium (Zr4+) is in the range of 0.2-2.0 g/L.
- The composition according to any one of the preceding claims, wherein the concentration of fluoride ions (F-) is in the range of 0.2-2.0 g/L.
- The composition according to any one of the preceding claims, wherein the concentration of stabilizing agent comprising a hydroxyl carboxylic acid or corresponding base(s) thereof (calculated as the acid) is in the range of 0.2-5 g/L, preferably 0.3-3 g/L.
- The composition according to any one of the preceding claims, wherein the pH is in the range of 3.4-4.4.
- The composition according to any one of the preceding claims comprising one or more of water soluble surfactants in a concentration of 0-1.0 g/L, preferably 0.001-0.5 g/L, pH adjusting agents in a concentration of 0-1.0 g/L, water soluble polymers, organo functional silanes or oligomers in a concentration of up to 4.0 g/L.
- A method of treating a substrate of aluminium, aluminium alloy, anodized aluminium, aluminized steel, zinc or zinc alloy coated steel for corrosion protection, adhesion of a coating or adhesive bonding system, which method comprises a step of applying the acidic aqueous solution according to any one of the preceding claims 1-7 to a substrate of aluminium, aluminium alloy, anodized aluminium, aluminized steel, zinc or zinc alloy coated steel.
- The method according to claim 8, wherein the composition has a temperature in the range of 10-80 °C, preferably 15-50 °C.
- The method according to claim 8 or 9, wherein the treatment time is 1-30 minutes, preferably 3-15 minutes.
- The method according to any one of the preceding claims 8-10, further comprising one or more steps of rinsing the treated substrate with demineralized water, wherein preferably the last rinsing step is carried out using demineralized water having a conductivity in the range of 5-200 microS, and more preferably a step of drying the rinsed substrate, in particular at a temperature of 10-50 °C.
- The method according to any one of the preceding claims 8-11, wherein the coating weight is in the range of 5-200 mg chromium/m2, as measured by XRF after drying.
- The method according to any one of the preceding claims 8-12, further comprising a step of after-treating the substrate that has been treated with the acidic aqueous composition according to any one of claims 1-7 with a second acidic aqueous composition comprising an oxidizing agent and an acidifying component and having a pH in the range of 1-5, preferably 1-3.
- The method according to claim 13, wherein the concentration of the oxidizing agent is in the range of 5-100 g/L, preferably 8-50 g/L, and/or wherein the oxidizing agent is a water soluble peroxide, preferably hydrogen peroxide,
- The method according to any one of the preceding claims 13-14, wherein the concentration of the acidifying component is in the range of 0.2-20.0 g/L, preferably 0.5-5.0 g/L, and/or wherein the acidic component is a salt of aluminium, zirconium or trivalent chromium, preferably a nitrate salt thereof.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
NL2017407 | 2016-09-02 | ||
NL2017768A NL2017768B1 (en) | 2016-09-02 | 2016-11-11 | Acidic aqueous composition for preparing a corrosion resistant coating on a metal substrate, method using the composition, and post-treatment composition |
Publications (2)
Publication Number | Publication Date |
---|---|
EP3301205A1 EP3301205A1 (en) | 2018-04-04 |
EP3301205B1 true EP3301205B1 (en) | 2019-10-09 |
Family
ID=59702650
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP17188823.3A Active EP3301205B1 (en) | 2016-09-02 | 2017-08-31 | Acidic aqueous composition for preparing a corrosion resistant coating on a metal substrate, method for treating the metal substrate by using the composition |
Country Status (1)
Country | Link |
---|---|
EP (1) | EP3301205B1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2024003504A1 (en) * | 2022-06-30 | 2024-01-04 | Safran Landing Systems | Aluminum alloy part and associated manufacturing process |
Families Citing this family (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP3822392A1 (en) * | 2019-11-15 | 2021-05-19 | Acondicionamiento Tarrasense | Method for polishing parts made of aluminum alloys comprising silicon |
CN112126921A (en) * | 2020-08-24 | 2020-12-25 | 安徽未来表面技术有限公司 | Aluminum and aluminum alloy trivalent chromium hydrophilic agent and preparation method thereof |
EP4244404A1 (en) * | 2020-11-10 | 2023-09-20 | Chemetall GmbH | Treatment of metallic surfaces by copolymer containing acidic aqueous compositions |
CN115247263A (en) * | 2022-06-20 | 2022-10-28 | 上海兴赛尔表面材料有限公司 | Environment-friendly passivation composition for tin plate and preparation method and application thereof |
WO2024039660A1 (en) * | 2022-08-16 | 2024-02-22 | Novelis Inc. | Pretreated aluminum alloy tab stock |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20060240191A1 (en) * | 2005-04-21 | 2006-10-26 | The U.S. Of America As Represented By The Secretary Of The Navy | Composition and process for preparing chromium-zirconium coatings on metal substrates |
JP5186642B2 (en) * | 2008-05-27 | 2013-04-17 | ユケン工業株式会社 | Finishing agent and member with overcoat formed from finishing agent |
JP5860582B2 (en) * | 2010-01-29 | 2016-02-16 | 日本パーカライジング株式会社 | Metal surface treatment agent and metal surface treatment method |
FR2986806B1 (en) * | 2012-02-10 | 2015-03-20 | Mecaprotec Ind | PROCESS FOR SURFACE TREATMENT OF ALUMINUM ALLOY OR MAGNESIUM ALLOYS |
-
2017
- 2017-08-31 EP EP17188823.3A patent/EP3301205B1/en active Active
Non-Patent Citations (1)
Title |
---|
None * |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2024003504A1 (en) * | 2022-06-30 | 2024-01-04 | Safran Landing Systems | Aluminum alloy part and associated manufacturing process |
FR3137393A1 (en) * | 2022-06-30 | 2024-01-05 | Safran Landing Systems | ALUMINUM ALLOY PART AND ASSOCIATED MANUFACTURING METHOD |
Also Published As
Publication number | Publication date |
---|---|
EP3301205A1 (en) | 2018-04-04 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP3301205B1 (en) | Acidic aqueous composition for preparing a corrosion resistant coating on a metal substrate, method for treating the metal substrate by using the composition | |
JP4242827B2 (en) | Metal surface treatment composition, surface treatment liquid, surface treatment method, and surface-treated metal material | |
EP1404894B1 (en) | Corrosion resistant coatings for aluminum and aluminum alloys | |
EP1163297B1 (en) | Method of treating metals using amino silanes and multi-silyl-functional silanes in admixture | |
CN100537845C (en) | Metal finishing treatment solution and surface treatment method | |
EP1997934B1 (en) | Composition for metal surface treatment, metal surface treatment method, and metal material | |
EP2094880B1 (en) | Process for treating metal surfaces | |
US20040244875A1 (en) | Method of surface treating metal and metal surface treated thereby | |
EP2576083B1 (en) | Corrosion resistant metallate compositions | |
EP1848841B1 (en) | Composition and process for preparing chromium-zirconium coatings on metal substrates | |
US20040163735A1 (en) | Chemical conversion coating agent and surface-treated metal | |
EP2458031A1 (en) | Chromium- and fluorine-free chemical conversion treatment solution for metal surfaces, metal surface treatment method, and metal surface coating method | |
JP5130226B2 (en) | Aqueous reaction solution and method for passivating workpieces with zinc or zinc alloy surfaces | |
KR100921116B1 (en) | Surface-treated metallic material | |
EP0719350B1 (en) | Metal treatment with acidic, rare earth ion containing cleaning solution | |
US4422886A (en) | Surface treatment for aluminum and aluminum alloys | |
US8241745B2 (en) | Essentially chromium-free method for passivating metallic surfaces consisting of Zn, Zn alloys, Al or Al alloys | |
JP2005325402A (en) | Surface treatment method for tin or tin based alloy plated steel | |
KR20100102619A (en) | Zirconium phosphating of metal components, in particular iron | |
US4391652A (en) | Surface treatment for aluminum and aluminum alloys | |
EP0032306B1 (en) | Aluminium-coating solution, process and concentrate | |
CN112135926A (en) | Trivalent chromium-based passivation composition | |
NL2017768B1 (en) | Acidic aqueous composition for preparing a corrosion resistant coating on a metal substrate, method using the composition, and post-treatment composition | |
JP3789553B2 (en) | Metal surface treatment agent, treatment method, and surface-treated metal material | |
US20040115448A1 (en) | Corrosion resistant magnesium and magnesium alloy and method of producing same |
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 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE APPLICATION HAS BEEN PUBLISHED |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR |
|
AX | Request for extension of the european patent |
Extension state: BA ME |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE |
|
17P | Request for examination filed |
Effective date: 20181002 |
|
RBV | Designated contracting states (corrected) |
Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR |
|
GRAP | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOSNIGR1 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: GRANT OF PATENT IS INTENDED |
|
INTG | Intention to grant announced |
Effective date: 20190128 |
|
GRAJ | Information related to disapproval of communication of intention to grant by the applicant or resumption of examination proceedings by the epo deleted |
Free format text: ORIGINAL CODE: EPIDOSDIGR1 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE |
|
GRAP | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOSNIGR1 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: GRANT OF PATENT IS INTENDED |
|
INTC | Intention to grant announced (deleted) | ||
INTG | Intention to grant announced |
Effective date: 20190424 |
|
GRAS | Grant fee paid |
Free format text: ORIGINAL CODE: EPIDOSNIGR3 |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE PATENT HAS BEEN GRANTED |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR |
|
REG | Reference to a national code |
Ref country code: GB Ref legal event code: FG4D |
|
REG | Reference to a national code |
Ref country code: CH Ref legal event code: EP |
|
REG | Reference to a national code |
Ref country code: IE Ref legal event code: FG4D |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R096 Ref document number: 602017007631 Country of ref document: DE |
|
REG | Reference to a national code |
Ref country code: AT Ref legal event code: REF Ref document number: 1188907 Country of ref document: AT Kind code of ref document: T Effective date: 20191115 |
|
REG | Reference to a national code |
Ref country code: NL Ref legal event code: MP Effective date: 20191009 |
|
REG | Reference to a national code |
Ref country code: LT Ref legal event code: MG4D |
|
REG | Reference to a national code |
Ref country code: AT Ref legal event code: MK05 Ref document number: 1188907 Country of ref document: AT Kind code of ref document: T Effective date: 20191009 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: LT Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20191009 Ref country code: PL Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20191009 Ref country code: SE Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20191009 Ref country code: BG Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20200109 Ref country code: NL Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20191009 Ref country code: ES Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20191009 Ref country code: LV Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20191009 Ref country code: NO Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20200109 Ref country code: GR Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20200110 Ref country code: PT Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20200210 Ref country code: FI Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20191009 Ref country code: AT Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20191009 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: RS Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20191009 Ref country code: IS Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20200224 Ref country code: HR Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20191009 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: AL Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20191009 |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R097 Ref document number: 602017007631 Country of ref document: DE |
|
PG2D | Information on lapse in contracting state deleted |
Ref country code: IS |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: CZ Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20191009 Ref country code: DK Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20191009 Ref country code: EE Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20191009 Ref country code: RO Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20191009 Ref country code: IS Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20200209 |
|
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 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: SK Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20191009 Ref country code: SM Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20191009 Ref country code: IT Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20191009 |
|
26N | No opposition filed |
Effective date: 20200710 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: SI Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20191009 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: MC Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20191009 |
|
REG | Reference to a national code |
Ref country code: CH Ref legal event code: PL |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: LI Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20200831 Ref country code: LU Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20200831 Ref country code: CH Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20200831 |
|
REG | Reference to a national code |
Ref country code: BE Ref legal event code: MM Effective date: 20200831 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: DE Payment date: 20210211 Year of fee payment: 4 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: FR Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20200831 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: IE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20200831 Ref country code: BE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20200831 |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R119 Ref document number: 602017007631 Country of ref document: DE |
|
GBPC | Gb: european patent ceased through non-payment of renewal fee |
Effective date: 20210831 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: TR Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20191009 Ref country code: MT Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20191009 Ref country code: CY Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20191009 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: MK Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20191009 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: GB Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20210831 Ref country code: DE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20220301 |