EP2671972B1 - Use of a solution containing phosphonic acid and/or phosphonic acid derivatives during the degreasing of metal surfaces, degreasing solution and method for degreasing a metal surface - Google Patents
Use of a solution containing phosphonic acid and/or phosphonic acid derivatives during the degreasing of metal surfaces, degreasing solution and method for degreasing a metal surface Download PDFInfo
- Publication number
- EP2671972B1 EP2671972B1 EP13168021.7A EP13168021A EP2671972B1 EP 2671972 B1 EP2671972 B1 EP 2671972B1 EP 13168021 A EP13168021 A EP 13168021A EP 2671972 B1 EP2671972 B1 EP 2671972B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- degreasing
- solution
- phosphonic acid
- surfactant
- metal surface
- 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
- 238000005238 degreasing Methods 0.000 title claims description 77
- 239000002184 metal Substances 0.000 title claims description 34
- 229910052751 metal Inorganic materials 0.000 title claims description 34
- ABLZXFCXXLZCGV-UHFFFAOYSA-N Phosphorous acid Chemical compound OP(O)=O ABLZXFCXXLZCGV-UHFFFAOYSA-N 0.000 title claims description 31
- 150000003007 phosphonic acid derivatives Chemical class 0.000 title claims description 28
- 238000000034 method Methods 0.000 title claims description 12
- 229940042400 direct acting antivirals phosphonic acid derivative Drugs 0.000 title description 5
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 35
- 229910052742 iron Inorganic materials 0.000 claims description 19
- 239000004094 surface-active agent Substances 0.000 claims description 19
- 238000005246 galvanizing Methods 0.000 claims description 17
- 239000002253 acid Substances 0.000 claims description 15
- 238000005554 pickling Methods 0.000 claims description 13
- 229910000831 Steel Inorganic materials 0.000 claims description 12
- 239000010959 steel Substances 0.000 claims description 12
- 239000003112 inhibitor Substances 0.000 claims description 11
- 239000002904 solvent Substances 0.000 claims description 7
- 150000007513 acids Chemical class 0.000 claims description 4
- -1 iron ions Chemical class 0.000 claims description 4
- 239000003205 fragrance Substances 0.000 claims description 3
- 238000009713 electroplating Methods 0.000 claims description 2
- 229910021645 metal ion Inorganic materials 0.000 claims description 2
- 239000000375 suspending agent Substances 0.000 claims 1
- 239000000243 solution Substances 0.000 description 69
- 150000003839 salts Chemical class 0.000 description 12
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 6
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 6
- 229910052725 zinc Inorganic materials 0.000 description 6
- 239000011701 zinc Substances 0.000 description 6
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 5
- 238000004140 cleaning Methods 0.000 description 4
- 239000012459 cleaning agent Substances 0.000 description 4
- 239000003921 oil Substances 0.000 description 4
- 238000001556 precipitation Methods 0.000 description 4
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 3
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 3
- MUBZPKHOEPUJKR-UHFFFAOYSA-N Oxalic acid Chemical compound OC(=O)C(O)=O MUBZPKHOEPUJKR-UHFFFAOYSA-N 0.000 description 3
- 239000003929 acidic solution Substances 0.000 description 3
- 230000002378 acidificating effect Effects 0.000 description 3
- 229910000147 aluminium phosphate Inorganic materials 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
- 238000005260 corrosion Methods 0.000 description 3
- 230000007797 corrosion Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 239000001257 hydrogen Substances 0.000 description 3
- 229910052739 hydrogen Inorganic materials 0.000 description 3
- 229910052500 inorganic mineral Inorganic materials 0.000 description 3
- 239000011707 mineral Substances 0.000 description 3
- 150000007524 organic acids Chemical class 0.000 description 3
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 2
- PIICEJLVQHRZGT-UHFFFAOYSA-N Ethylenediamine Chemical compound NCCN PIICEJLVQHRZGT-UHFFFAOYSA-N 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- YDONNITUKPKTIG-UHFFFAOYSA-N [Nitrilotris(methylene)]trisphosphonic acid Chemical compound OP(O)(=O)CN(CP(O)(O)=O)CP(O)(O)=O YDONNITUKPKTIG-UHFFFAOYSA-N 0.000 description 2
- 239000000654 additive Substances 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 2
- 239000011248 coating agent Substances 0.000 description 2
- 238000000576 coating method Methods 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 238000009792 diffusion process Methods 0.000 description 2
- 239000003925 fat Substances 0.000 description 2
- 230000004907 flux Effects 0.000 description 2
- VKYKSIONXSXAKP-UHFFFAOYSA-N hexamethylenetetramine Chemical compound C1N(C2)CN3CN1CN2C3 VKYKSIONXSXAKP-UHFFFAOYSA-N 0.000 description 2
- NAQMVNRVTILPCV-UHFFFAOYSA-N hexane-1,6-diamine Chemical compound NCCCCCCN NAQMVNRVTILPCV-UHFFFAOYSA-N 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 2
- 239000002736 nonionic surfactant Substances 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- 239000002244 precipitate Substances 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- UMGDCJDMYOKAJW-UHFFFAOYSA-N thiourea Chemical compound NC(N)=S UMGDCJDMYOKAJW-UHFFFAOYSA-N 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- SZHQPBJEOCHCKM-UHFFFAOYSA-N 2-phosphonobutane-1,2,4-tricarboxylic acid Chemical compound OC(=O)CCC(P(O)(O)=O)(C(O)=O)CC(O)=O SZHQPBJEOCHCKM-UHFFFAOYSA-N 0.000 description 1
- JKTORXLUQLQJCM-UHFFFAOYSA-N 4-phosphonobutylphosphonic acid Chemical compound OP(O)(=O)CCCCP(O)(O)=O JKTORXLUQLQJCM-UHFFFAOYSA-N 0.000 description 1
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 1
- FEWJPZIEWOKRBE-JCYAYHJZSA-N Dextrotartaric acid Chemical compound OC(=O)[C@H](O)[C@@H](O)C(O)=O FEWJPZIEWOKRBE-JCYAYHJZSA-N 0.000 description 1
- 208000035220 Dyserythropoietic Congenital Anemia Diseases 0.000 description 1
- DBVJJBKOTRCVKF-UHFFFAOYSA-N Etidronic acid Chemical compound OP(=O)(O)C(O)(C)P(O)(O)=O DBVJJBKOTRCVKF-UHFFFAOYSA-N 0.000 description 1
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 1
- YSMRWXYRXBRSND-UHFFFAOYSA-N TOTP Chemical compound CC1=CC=CC=C1OP(=O)(OC=1C(=CC=CC=1)C)OC1=CC=CC=C1C YSMRWXYRXBRSND-UHFFFAOYSA-N 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
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Natural products NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 description 1
- PTFCDOFLOPIGGS-UHFFFAOYSA-N Zinc dication Chemical compound [Zn+2] PTFCDOFLOPIGGS-UHFFFAOYSA-N 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 239000012670 alkaline solution Substances 0.000 description 1
- 125000000129 anionic group Chemical group 0.000 description 1
- 239000003945 anionic surfactant Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000003093 cationic surfactant Substances 0.000 description 1
- 235000015165 citric acid Nutrition 0.000 description 1
- 230000000536 complexating effect Effects 0.000 description 1
- 239000000356 contaminant Substances 0.000 description 1
- 239000003599 detergent Substances 0.000 description 1
- 150000004985 diamines Chemical class 0.000 description 1
- 150000002009 diols Chemical class 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- DUYCTCQXNHFCSJ-UHFFFAOYSA-N dtpmp Chemical compound OP(=O)(O)CN(CP(O)(O)=O)CCN(CP(O)(=O)O)CCN(CP(O)(O)=O)CP(O)(O)=O DUYCTCQXNHFCSJ-UHFFFAOYSA-N 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 239000004312 hexamethylene tetramine Substances 0.000 description 1
- 235000010299 hexamethylene tetramine Nutrition 0.000 description 1
- GNOIPBMMFNIUFM-UHFFFAOYSA-N hexamethylphosphoric triamide Chemical compound CN(C)P(=O)(N(C)C)N(C)C GNOIPBMMFNIUFM-UHFFFAOYSA-N 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- WBJZTOZJJYAKHQ-UHFFFAOYSA-K iron(3+) phosphate Chemical class [Fe+3].[O-]P([O-])([O-])=O WBJZTOZJJYAKHQ-UHFFFAOYSA-K 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- RTWNYYOXLSILQN-UHFFFAOYSA-N methanediamine Chemical compound NCN RTWNYYOXLSILQN-UHFFFAOYSA-N 0.000 description 1
- 239000002480 mineral oil Substances 0.000 description 1
- 235000010446 mineral oil Nutrition 0.000 description 1
- 229910017604 nitric acid Inorganic materials 0.000 description 1
- 229910017464 nitrogen compound Inorganic materials 0.000 description 1
- 150000002830 nitrogen compounds Chemical group 0.000 description 1
- QJGQUHMNIGDVPM-UHFFFAOYSA-N nitrogen group Chemical group [N] QJGQUHMNIGDVPM-UHFFFAOYSA-N 0.000 description 1
- 235000005985 organic acids Nutrition 0.000 description 1
- 150000002898 organic sulfur compounds Chemical class 0.000 description 1
- 235000006408 oxalic acid Nutrition 0.000 description 1
- 239000003973 paint Substances 0.000 description 1
- 238000010422 painting Methods 0.000 description 1
- 238000005498 polishing Methods 0.000 description 1
- 230000008092 positive effect Effects 0.000 description 1
- 238000012805 post-processing Methods 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 238000005488 sandblasting Methods 0.000 description 1
- 239000010865 sewage Substances 0.000 description 1
- 238000004381 surface treatment Methods 0.000 description 1
- 235000002906 tartaric acid Nutrition 0.000 description 1
- 239000011975 tartaric acid Substances 0.000 description 1
- 238000009736 wetting Methods 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
- C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
- C23G1/00—Cleaning or pickling metallic material with solutions or molten salts
- C23G1/02—Cleaning or pickling metallic material with solutions or molten salts with acid solutions
- C23G1/08—Iron or steel
- C23G1/088—Iron or steel solutions containing organic acids
Definitions
- the present invention relates to the use of a degreasing solution and a method for degreasing an iron or steel surface during hot-dip galvanizing or galvanic treatment of the metal surface.
- the EP 1 310 306 A1 discloses a cleaning process that is assisted by sound waves.
- the cleaning agent used is intended, on the one hand, to reduce hydrogen embrittlement and has a pH value greater than 4.0, in particular greater than 5.0.
- a degreasing solution is used according to claim 1.
- Degreasing in this case means the removal of oils or fats from the metal surface.
- the use according to the invention can also surprisingly increase the service life of baths.
- the solution itself can be used as a bath can be used or added to a solution in the bath during or after a degreasing process in order to adjust the salt concentration of the bath, which changes due to degreasing.
- a particularly favorable proportion of phosphonic acid or the phosphonic acid derivative is 0.0001 to 50% by weight, based on the total amount of free acid in a solution used for degreasing or pickling, in particular the bath solution.
- the solution containing phosphonic acid or phosphonic acid derivative has a pH of less than 4.0.
- a degreasing solution for use in degreasing iron or steel surfaces contains a phosphonic acid and / or a phosphonic acid derivative and a surfactant.
- the salt concentration of the solution can be adjusted by the phosphonic acid and / or the phosphonic acid derivative in such a way that the degreasing effect of the surfactant is maintained over a long period of time.
- Such a degreasing solution can be used for a bath for degreasing a metal surface during hot-dip galvanizing, whereby a long service life of the bath is achieved.
- the degreasing solution can also only be provided after a few degreasing passes by adding phosphonic acid or phosphonic acid derivatives to a surfactant-containing solution.
- the degreasing solution also has one or more other acids, the solution having a pH of less than 4.0. This also helps reduce the salt concentration of the degreasing solution through precipitation.
- the degreasing solution has a phosphonic acid content of 0.0001 to 50%, based on the amount of free acid in the degreasing solution.
- a particularly good degreasing of a metal surface takes place with a surfactant content of 0.01 to 10% by weight.
- the degreasing solution can additionally contain at least one solvent, an inhibitor, a solubilizer, an adjusting agent and / or a fragrance in a concentration of 0.001 to 10% by weight.
- the degreasing solution can be used as a bath for degreasing iron steel surfaces in hot-dip galvanizing or electroplating.
- the surfactant-containing solution can be adjusted depending on the salt content after each degreasing or after several degreasing operations, so that the service life of the surfactant-containing solution can be increased.
- a proportion of the phosphonic acid or the phosphonic acid derivative in the solution in step c) of 0.0001 to 10% is sufficient.
- an iron or steel surface is provided with a zinc layer, which is partially diffused into the surface. At the same time, some of the iron molecules diffuse from the iron or steel surface into the zinc layer. This is done before the actual zinc layer is applied various known preparatory steps are used, which among other things depend on the quality of the surface to be coated.
- an abrasive surface treatment in the form of sandblasting or the like can take place in order to remove rust or paint residues from the surface.
- a pickling treatment is carried out to remove impurities that can be traced back to the metal itself. These are, for example, oxidation products such as rust or scale.
- the duration of the pickling process and the concentration of the pickling bath depend on the extent of the oxidation products occurring on the metal surface.
- degreasing is also carried out in the pickling area, in which case it is called pickling degreasing.
- fluxing can also be carried out using a layer of salt that floats on the zinc bath (so-called wet galvanizing).
- wet galvanizing a layer of salt that floats on the zinc bath
- the surfaces to be treated should not be dried before galvanizing.
- the metal surface can be dried, for example in drying ovens at 80-90 ° C.
- post-processing steps such as deburring, plastering, polishing, painting or powder coating can take place.
- hot-dip galvanizing plants usually do not have a sewage system, but only so-called standing sinks. The substances used in hot-dip galvanizing are thus carried over into the subsequent baths. These baths are gradually used up and have to be disposed of externally. In order to minimize environmental pollution and achieve a corresponding reduction in costs, a longer service life for bathrooms should be aimed for.
- a bath is generally considered exhausted when the iron concentration and thus the salt concentration of the degreasing solution exceeds a certain level, so that the degreasing surfactants contained in the bath and the impurities kept in solution by the surfactants are no longer stable or soluble in the degreasing solution are present.
- the salt concentration is usually increased automatically in acidic solutions, since iron ions are inevitably dissolved in the degreasing solution with every degreasing process.
- a known way of increasing the service life is the use of phosphoric acid.
- iron phosphates are precipitated, as a result of which the iron concentration and thus also the salt concentration of the solution - based on the ions in solution - are reduced overall.
- the subject matter of the present invention takes an alternative route by adding a cleaning agent or a solution containing a phosphonic acid or a phosphonic acid derivative to the degreasing solution.
- the addition of the cleaning agent containing phosphonic acid derivatives surprisingly forms a precipitate which, on the one hand, binds the excess iron.
- organic contaminants are removed from the bath.
- Such a phosphonic acid derivative is preferably HEDP (1-hydroxyethane (1,1-diphosphonic acid), HEMPA (hexamethylene diamine tetra (methylene phosphonic acid)), HDTMP (hexaethylene diamine tetramethylene phosphonic acid), ATMP (aminotrimethylene phosphonic acid), methylene diamine phosphonic acid, EDTMP (ethylene diamine phosphonic acid), EDTMP (ethylene diamine phosphonic acid) (Diethylenetriaminepenta (methylenephosphonic acid)) and / or PBTC (2-phosphonobutane-1,2,4-tricarboxylic acid).
- HEMPA hexamethylene diamine tetra (methylene phosphonic acid)
- HDTMP hexaethylene diamine tetramethylene phosphonic acid
- ATMP aminotrimethylene phosphonic acid
- EDTMP ethylene diamine phosphonic acid
- EDTMP ethylene diamine phosphonic acid
- a preferred dosage of a phosphonic acid derivative can adjust the iron content in the solution of the bath, which practically leads to an almost unlimited service life of the bath.
- the phosphonic acid derivative can be a derivative of a simple or complex phosphonic acid.
- the detergent added has a pH value of less than 4.0.
- the degreasing solution made from the cleaning agent is used for degreasing an iron or steel surface during hot-dip galvanizing or during the galvanic treatment of metal surfaces.
- the concentration of phosphonic acid or a phosphonic acid derivative in the degreasing solution is preferably 0.0001 to 50%, in particular 0.1 to 10%, based on the amount of free acid present in the degreasing solution.
- the degreasing solution always contains at least one acid.
- a phosphonic acid can also be added separately to an existing cleaning solution for metal precipitation.
- phosphonic acid or a phosphonic acid derivative of preferably 0.0001 to 10%, in particular 0.01 to 1%, based on the amount of free acid present, can be added in added to the degreasing solution.
- a mineral acid and / or an organic acid can also be added in order to achieve increased cleaning or precipitation.
- Preferred mineral acids are hydrochloric acid, sulfuric acid, phosphoric acid and / or nitric acid.
- Preferred organic acids are oxalic acid, tartaric acid, citric acid and / or acetic acid.
- the concentration of the mineral acid and / or organic acid in the degreasing solution is preferably 0.1 to 90% by weight, based on the total weight of the solution.
- the degreasing solution contains surfactants, in particular nonionic, anionic and / or cationic surfactants, a proportion of phosphonic acid or phosphonic acid derivative having a particularly positive effect on the solubility of nonionic surfactants, in particular in a particularly preferred concentration of 0.01 to 10 wt. %, in particular 0.1-1% by weight based on the total weight of the degreasing solution.
- surfactants in particular nonionic, anionic and / or cationic surfactants
- a proportion of phosphonic acid or phosphonic acid derivative having a particularly positive effect on the solubility of nonionic surfactants in particular in a particularly preferred concentration of 0.01 to 10 wt. %, in particular 0.1-1% by weight based on the total weight of the degreasing solution.
- the degreasing solution can also contain inhibitors in order to minimize the absorption of iron ions from the treated metal surfaces.
- Inhibitors on the one hand, reduce the uptake of metal and, on the other hand, reduce the formation of hydrogen and, in some cases, are also intended to reduce the diffusion of hydrogen into the metal structure.
- the service life of pickling is increased because the metal content then increases more slowly. That is why the inhibitor-containing pickling solutions are sometimes also referred to as economy pickling.
- the inhibitors are usually substances which cover the metal surface with a coating, sometimes a monomolecular film.
- inhibitors are unsaturated diols such as butynediol or its derivatives, organic sulfur compounds such as thiourea or its derivatives or nitrogen-containing compounds such as hexamethylenetetramine or quaternary nitrogen compounds or other inhibitors. These are present in a concentration of 0.01-1% by weight, based on the total weight of the solution.
- Further preferred additives to the degreasing solution are solvents, solubilizers, adjusting agents and / or fragrances, each in a preferred concentration of 0.001 to 10% by weight, in particular in a concentration of 0.01 to 5% by weight.
Description
Die vorliegende Erfindung betrifft eine Verwendung einer entfettenden Lösung, sowie Verfahren zur Entfettung einer Eisen- oder Stahloberfläche bei der Feuerverzinkung oder der galvanischen Behandlung der Metalloberfläche.The present invention relates to the use of a degreasing solution and a method for degreasing an iron or steel surface during hot-dip galvanizing or galvanic treatment of the metal surface.
Es sind Verfahren bei der Feuerverzinkung bekannt, bei welchen saure Lösungen zur Entfettung von Metalloberflächen verwendet werden, insbesondere Salzsäurelösungen oder Phosphorsäurelösungen, um die Standzeit von Bädern zu erhöhen.Methods are known in hot-dip galvanizing in which acidic solutions are used to degrease metal surfaces, in particular hydrochloric acid solutions or phosphoric acid solutions, in order to increase the service life of baths.
Die
Als weiterer relevanter Stand der Technik ist die
Es ist Aufgabe der vorliegenden Erfindung, die Standzeit von Bädern bei der Entfettung von Metalloberflächen zusätzlich zu erhöhen.It is the object of the present invention to additionally increase the service life of baths when degreasing metal surfaces.
Die Erfindung löst diese Aufgabe durch die Merkmale der Ansprüche 1 bis 7.The invention solves this problem with the features of claims 1 to 7.
Erfindungsgemäß erfolgt eine Verwendung einer entfettenden Lösung gemäß Anspruch 1. Entfettung bedeutet in diesem Fall die Entfernung von Ölen oder Fetten von der Metalloberfläche.According to the invention, a degreasing solution is used according to claim 1. Degreasing in this case means the removal of oils or fats from the metal surface.
Durch die erfindungsgemäße Verwendung kann die Standzeit von Bädern zusätzlich überraschend erhöht werden. Dabei kann die Lösung selbst als Bad genutzt werden oder während oder nach eines Entfettungsvorganges in eine Lösung im Bad zugegeben werden, um die sich durch die Entfettung ändernde Salzkonzentration des Bades einzustellen.The use according to the invention can also surprisingly increase the service life of baths. The solution itself can be used as a bath can be used or added to a solution in the bath during or after a degreasing process in order to adjust the salt concentration of the bath, which changes due to degreasing.
Vorteilhafte Ausgestaltungen der Erfindung sind Gegenstand der Unteransprüche.Advantageous refinements of the invention are the subject matter of the subclaims.
Ein besonders günstiger Anteil an Phosphonsäure oder des Phosphonsäurederivates beträgt 0,0001 bis 50 Gew.%, bezogen auf die Gesamtmenge an freier Säure in einer zur Entfettung bzw. Beizung verwendeten Lösung, insbesondere der Badlösung, beträgt.A particularly favorable proportion of phosphonic acid or the phosphonic acid derivative is 0.0001 to 50% by weight, based on the total amount of free acid in a solution used for degreasing or pickling, in particular the bath solution.
Um einen möglichst optimalen Fällungsniederschlag zur Senkung der Salzkonzentration in der entfettenden Lösung des Bades zu erreichen, ist es von Vorteil, wenn die phosphonsäurehaltige oder phosphonsäurederivathaltige Lösung einen pH-Wert von weniger als 4,0, aufweist.In order to achieve the best possible precipitation for lowering the salt concentration in the degreasing solution of the bath, it is advantageous if the solution containing phosphonic acid or phosphonic acid derivative has a pH of less than 4.0.
Erfindungsgemäß enthält eine entfettende Lösung zur Verwendung bei der Entfettung von Eisen- oder Stahloberflächen, eine Phosphonsäure und/oder ein Phosphonsäurederivat und ein Tensid. Durch die Phosphonsäure und/oder das Phosphonsäurederivat kann die Salzkonzentration der Lösung derart eingestellt werden, dass die entfettende Wirkung des Tensids über lange Zeit aufrechterhalten wird. Eine solche entfettende Lösung kann für ein Bad zur Entfettung einer Metalloberfläche bei Feuerverzinkung eingesetzt werden, wodurch eine hohe Standzeit des Bades erzielt wird. Dabei kann die entfettende Lösung auch erst nach einigen Entfettungsdurchgängen durch Zugabe von Phosphonsäure oder Phosphonsäurederivaten zu einer tensidhaltigen Lösung bereitgestellt werden.According to the invention, a degreasing solution for use in degreasing iron or steel surfaces contains a phosphonic acid and / or a phosphonic acid derivative and a surfactant. The salt concentration of the solution can be adjusted by the phosphonic acid and / or the phosphonic acid derivative in such a way that the degreasing effect of the surfactant is maintained over a long period of time. Such a degreasing solution can be used for a bath for degreasing a metal surface during hot-dip galvanizing, whereby a long service life of the bath is achieved. The degreasing solution can also only be provided after a few degreasing passes by adding phosphonic acid or phosphonic acid derivatives to a surfactant-containing solution.
Unterstützend weist dabei die entfettende Lösung, zusätzlich zur Phosphonsäure oder dem Phosphonsäurederivat, eine oder mehrere weitere Säuren auf, wobei die Lösung einen pH-Wert von weniger als 4,0, aufweist. Dadurch wird die Verringerung der Salzkonzentration der entfettenden Lösung durch Fällung zusätzlich unterstützt.In addition to the phosphonic acid or the phosphonic acid derivative, the degreasing solution also has one or more other acids, the solution having a pH of less than 4.0. This also helps reduce the salt concentration of the degreasing solution through precipitation.
Optimalerweise weist die entfettende Lösung einen Gehalt an Phosphonsäure von 0,0001 bis 50%, bezogen auf die Menge an freier Säure in der entfettenden Lösung, auf.Optimally, the degreasing solution has a phosphonic acid content of 0.0001 to 50%, based on the amount of free acid in the degreasing solution.
Eine besonders gute Entfettung einer Metalloberfläche findet bei einem Tensidgehalt von 0,01 bis 10 Gew.% statt.A particularly good degreasing of a metal surface takes place with a surfactant content of 0.01 to 10% by weight.
Weiterhin kann die entfettende Lösung zusätzlich zumindest ein Lösungsmittel, einen Inhibitor, einen Lösevermittler, ein Stellmittel und/oder einen Duftstoff in einer Konzentration von 0,001 bis 10 Gew.% enthalten.Furthermore, the degreasing solution can additionally contain at least one solvent, an inhibitor, a solubilizer, an adjusting agent and / or a fragrance in a concentration of 0.001 to 10% by weight.
Die entfettende Lösung kann als Bad zur Entfettung von Eisen Stahloberflächen bei der Feuerverzinkung oder in der Galvanotechnik verwendet werden.The degreasing solution can be used as a bath for degreasing iron steel surfaces in hot-dip galvanizing or electroplating.
Erfindungsgemäß weist ein Verfahren zur Entfettung einer Eisen- oder Stahloberfläche bei der Feuerverzinkung oder der galvanischen Behandlung der Metalloberfläche, die folgenden Schritte auf:
- a) Vorlage einer tensidhaltigen Lösung mit einem pH-Wert von weniger als 4,0 zur Entfettung der Metalloberfläche,
- b) Entfetten der Metalloberfläche durch Einbringen in die tensidhaltige Lösung; und
- c) Zugabe einer phosphonsäure- und/oder phosphonsäurederivathaltigen Lösung vor, während oder nach dem Entfetten der Metalloberfläche in die tensidhaltige Lösung zur Verminderung des Salzgehaltes in der Lösung, wobei die gebildete Lösung zusätzlich zur Phosphonsäure oder dem Phosphonsäurederivat eine oder mehrere weitere Säuren aufweist.
- a) Submission of a surfactant-containing solution with a pH value of less than 4.0 for degreasing the metal surface,
- b) degreasing the metal surface by introducing it into the surfactant-containing solution; and
- c) Adding a solution containing phosphonic acid and / or phosphonic acid derivative before, during or after degreasing the metal surface in the surfactant-containing solution to reduce the salt content in the solution, the resulting solution having one or more other acids in addition to the phosphonic acid or the phosphonic acid derivative.
Durch die Zugabe der phosphonsäure- und/oder phosphonsäurederivathaltigen Lösung in Schritt c) kann eine Einstellung der tensidhaltigen Lösung in Abhängigkeit vom Salzgehalt nach jeder Entfettung oder nach mehreren Entfettungen erfolgen, so dass die Standzeit der tensidhaltigen Lösung erhöht werden kann.By adding the phosphonic acid and / or phosphonic acid derivative-containing solution in step c), the surfactant-containing solution can be adjusted depending on the salt content after each degreasing or after several degreasing operations, so that the service life of the surfactant-containing solution can be increased.
Um eine materialsparende Dosierung zu ermöglichen, ist ein Anteil der Phosphonsäure oder des Phosphonsäurederivates in der Lösung in Schritt c) von 0,0001 bis 10% ausreichend.In order to enable material-saving metering, a proportion of the phosphonic acid or the phosphonic acid derivative in the solution in step c) of 0.0001 to 10% is sufficient.
Die erfindungsgemäße Verwendung wird nachfolgend anhand eines bevorzugten Ausführungsbeispiels näher erläutert.The use according to the invention is explained in more detail below with reference to a preferred exemplary embodiment.
Bei der Feuerverzinkung wird eine Eisen- oder Stahloberfläche mit einer Zinkschicht versehen, welche teilweise in die Oberfläche eindiffundiert ist. Zugleich diffundiert ein Teil der Eisenmoleküle aus der Eisen- oder Stahloberfläche in die Zinkschicht. Dabei werden vor dem Aufbringen der eigentlichen Zinkschicht verschiedene bekannte vorbereitende Schritte angewandt, welche u.a. von der Güte der zu beschichtenden Oberfläche abhängen.In hot-dip galvanizing, an iron or steel surface is provided with a zinc layer, which is partially diffused into the surface. At the same time, some of the iron molecules diffuse from the iron or steel surface into the zinc layer. This is done before the actual zinc layer is applied various known preparatory steps are used, which among other things depend on the quality of the surface to be coated.
In einem optionalen ersten Schritt kann beispielsweise eine abrasive Oberflächenbehandlung in Form von Sandbestrahlen o.ä. erfolgen, um Rost oder Lackrückstände von der Oberfläche zu entfernen.In an optional first step, for example, an abrasive surface treatment in the form of sandblasting or the like can take place in order to remove rust or paint residues from the surface.
Im Anschluss daran erfolgt ein Entfetten der zu beschichtenden metallischen Oberflächen oder der Metallteile insgesamt. Üblicherweise werden hierfür saure oder alkalische Lösungen verwandt. Oft weisen beispielsweise Eisen- oder Stahloberflächen bei der Lieferung einen Mineralölfilm auf, um einer Korrosion vorzubeugen. Dieser Ölfilm kann zusätzlich einen Korrosionsschutz und weitere Additive enthalten. Bei der Verzinkung ist dieser Ölfilm allerdings hinderlich, da er eine Kontaktierung der Zinkionen mit der Stahl- oder Eisenoberfläche behindert. Somit ist ein Entfetten der Metalloberfläche notwendig.This is followed by degreasing the metal surfaces to be coated or the metal parts as a whole. Acidic or alkaline solutions are usually used for this. For example, iron or steel surfaces often have a mineral oil film on delivery to prevent corrosion. This oil film can also contain corrosion protection and other additives. However, this oil film is a hindrance during galvanizing because it prevents the zinc ions from coming into contact with the steel or iron surface. It is therefore necessary to degrease the metal surface.
Nach dem Entfetten kann eine Spülung in Wasser erfolgen, um die Verschleppung in die nachfolgenden Bäder (meist saure Beizlösungen) zu vermeiden bzw. zu minimieren.After degreasing, it can be rinsed in water in order to avoid or minimize the carry-over into the subsequent baths (mostly acidic pickling solutions).
Nach dem Entfetten bzw. Spülen erfolgt eine Beizbehandlung zum Entfernen von Verunreinigungen, welche sich auf das Metall selbst zurückführen lassen. Dies sind beispielsweise Oxidationsprodukte, wie Rost oder Zunder. Die Dauer des Beizvorgangs und die Konzentration des Beizbades hängen vom Umfang der auf der Metalloberfläche vorkommenden Oxidationsprodukte ab. In einigen Fällen wird die Entfettung auch in der Beize durchgeführt, dann spricht man vom Beizentfetten.After degreasing or rinsing, a pickling treatment is carried out to remove impurities that can be traced back to the metal itself. These are, for example, oxidation products such as rust or scale. The duration of the pickling process and the concentration of the pickling bath depend on the extent of the oxidation products occurring on the metal surface. In some cases, degreasing is also carried out in the pickling area, in which case it is called pickling degreasing.
Um Säure- und Salzreste nicht in nachfolgende Verfahrensstufen zu verschleppen, kann im Anschluss an das Beizen ein weiteres Spülen mit Lösungsmittel - beispielsweise Wasser - durchgeführt werden.In order to prevent acid and salt residues from being carried over into the subsequent process stages, a further rinsing with solvent - for example water - can be carried out after the pickling.
Nach dem Beizen oder Spülen ist es außerdem üblich, die metallische Oberfläche einer Feinstreinigung in einem chloridhaltigen Flussmittelbad (dieser Prozeß wird Fluxen genannt, bei einer wässrigen Anwendung üblicherweise Trockenflux) zu unterziehen, um die Stahloberfläche zu aktivieren und damit die Benetzungsfähigkeit zu erhöhen.After pickling or rinsing, it is also customary to subject the metallic surface to fine cleaning in a chloride-containing flux bath (this process is called fluxing, in an aqueous application usually dry flux) in order to activate the steel surface and thus increase the wetting ability.
Ersatzweise kann das Fluxen auch mittels einer Salzschicht, welche auf dem Zinkbad schwimmt, durchgeführt werden (sogenanntes Nassverzinken). In diesem Fall sollte die zu behandelnden Oberflächen vor dem Verzinken nicht getrocknet werden.As an alternative, fluxing can also be carried out using a layer of salt that floats on the zinc bath (so-called wet galvanizing). In this In this case, the surfaces to be treated should not be dried before galvanizing.
Nach dem Fluxen kann ein Trocknen der Metalloberfläche, beispielsweise in Trockenöfen bei 80-90°C, erfolgen.After the fluxing, the metal surface can be dried, for example in drying ovens at 80-90 ° C.
Im Anschluss erfolgt das Verzinken durch Eintauchen der metallischen Oberfläche in eine flüssige Zinkschmelze, mit vorzugsweise mindestens 98 Gew.-% Zink. Diese weist vorzugsweise eine Temperatur von mehr als 420°C auf, besonders bevorzugt zwischen 440-465°C, oder alternativ oberhalb von 500°C. Dabei erfolgt eine wechselseitige Diffusion beider Metallschichten ineinander.This is followed by galvanizing by immersing the metallic surface in a liquid zinc melt, preferably with at least 98% by weight zinc. This preferably has a temperature of more than 420 ° C, particularly preferably between 440-465 ° C, or alternatively above 500 ° C. There is a mutual diffusion of the two metal layers into one another.
Im Anschluss an das Verzinken können nachbearbeitende Arbeitsschritte, z.B. Entgraten, Verputzen, Polieren, Lackieren oder Pulverbeschichten erfolgen.Subsequent to galvanizing, post-processing steps such as deburring, plastering, polishing, painting or powder coating can take place.
Zusätzlich kann ein sogenanntes Entzinken in verdünnter Salzsäure erfolgen, bei dem bereits verzinkte Metallschichten wieder entfernt werden können. Dadurch kann eine Fehlverzinkung wieder abgelöst werden
Feuerverzinkereien haben allerdings üblicherweise keine Abwasseranlage, sondern nur sogenannte Standspülen. Die in der Feuerverzinkung eingesetzten Stoffe werden somit in nachfolgende Bäder verschleppt. Diese Bäder sind nach und nach verbraucht und müssen extern entsorgt werden. Um die Umweltbelastungen zu minimieren und eine entsprechende Kostensenkung zu erreichen, sollte eine längere Standzeit von Bädern angestrebt werden.In addition, so-called dezincing can be carried out in dilute hydrochloric acid, during which metal layers that have already been galvanized can be removed again. This means that incorrect galvanizing can be replaced again
However, hot-dip galvanizing plants usually do not have a sewage system, but only so-called standing sinks. The substances used in hot-dip galvanizing are thus carried over into the subsequent baths. These baths are gradually used up and have to be disposed of externally. In order to minimize environmental pollution and achieve a corresponding reduction in costs, a longer service life for bathrooms should be aimed for.
Ein Bad gilt in der Regel dann als erschöpft, wenn die Eisenkonzentration und somit die Salzkonzentration der entfettenden Lösung einen bestimmten Gehalt überschreitet, so dass die im Bad enthaltenen entfettungswirksamen Tenside und die von den Tensiden in Lösung gehaltenen Verunreinigungen nicht mehr stabil oder löslich in der Entfettungslösung vorliegen. Eine Erhöhung der Salzkonzentration erfolgt dabei in sauren Lösungen in der Regel ganz automatisch, da bei jedem Entfettungsvorgang zwangsläufig auch Eisenionen in der entfettenden Lösung gelöst werden.A bath is generally considered exhausted when the iron concentration and thus the salt concentration of the degreasing solution exceeds a certain level, so that the degreasing surfactants contained in the bath and the impurities kept in solution by the surfactants are no longer stable or soluble in the degreasing solution are present. The salt concentration is usually increased automatically in acidic solutions, since iron ions are inevitably dissolved in the degreasing solution with every degreasing process.
Eine bekannte Möglichkeit zur Erhöhung der Standzeit ist der Einsatz von Phosphorsäure. Dadurch werden Eisenphosphate ausgefällt, wodurch die Eisenkonzentration und somit auch die Salzkonzentration der Lösung - bezogen auf die in Lösung befindlichen Ionen - insgesamt gesenkt wird.A known way of increasing the service life is the use of phosphoric acid. As a result, iron phosphates are precipitated, as a result of which the iron concentration and thus also the salt concentration of the solution - based on the ions in solution - are reduced overall.
Der Gegenstand der vorliegenden Erfindung beschreitet demgegenüber einen alternativen Weg, indem der entfettenden Lösung ein Reinigungsmittel bzw. eine Lösung enthaltend eine Phosphonsäure oder ein Phosphonsäurederivat zugesetzt wird. Durch den Zusatz des phosphonsäurederivathaltigen Reinigungsmittels bildet sich überraschend ein Niederschlag aus, welcher einerseits das überschüssige Eisen bindet. Zusätzlich werden organische Verunreinigungen aus dem Bad entfernt.In contrast, the subject matter of the present invention takes an alternative route by adding a cleaning agent or a solution containing a phosphonic acid or a phosphonic acid derivative to the degreasing solution. The addition of the cleaning agent containing phosphonic acid derivatives surprisingly forms a precipitate which, on the one hand, binds the excess iron. In addition, organic contaminants are removed from the bath.
Dies ist insoweit überraschend, da Phosphonsäurederivate eigentlich als komplexierend gelten und durch deren Zusatz die Salzkonzentration weiter erhöht wird. Trotz alledem wird die Standzeit eines Bades durch den Zusatz dieser Derivate drastisch erhöht, so dass eine Entfettungswirkung des Bades über einen längeren Zeitpunkt aufrecht erhalten bleibt.This is surprising insofar as phosphonic acid derivatives are actually considered to be complexing and their addition further increases the salt concentration. In spite of all this, the service life of a bath is drastically increased by adding these derivatives, so that the degreasing effect of the bath is maintained over a longer period of time.
Vorzugsweise ist ein solches Phosphonsäurederivat HEDP (1-Hydroxyethan-(1,1-diphosphonsäure), HEMPA (Hexamethylendiamin-tetra(methylenphosphonsäure)), HDTMP (Hexaethylenediamine-tetramethylenphosphonsäure), ATMP (Aminotrimethylenphosphonsäure), EDTMP (Ethylendiamintetra(methylenphosphonsäure)), DTPMP (Diethylentriaminpenta(methylenphosphonsäure)) und/oder PBTC (2-Phosphonobutan-1,2,4-tricarbonsäure). Diese Verbindungen werden üblicherweise als Korrosionsinhibitoren eingesetzt und/oder dienen dazu, Metallionen in Lösung zu halten. Interessanterweise konnte trotzdem die Bildung eines Niederschlages bei der Zugabe einer der vorgenannten Verbindungen zu einer entfettenden Lösung beobachtet werden.Such a phosphonic acid derivative is preferably HEDP (1-hydroxyethane (1,1-diphosphonic acid), HEMPA (hexamethylene diamine tetra (methylene phosphonic acid)), HDTMP (hexaethylene diamine tetramethylene phosphonic acid), ATMP (aminotrimethylene phosphonic acid), methylene diamine phosphonic acid, EDTMP (ethylene diamine phosphonic acid), EDTMP (ethylene diamine phosphonic acid) (Diethylenetriaminepenta (methylenephosphonic acid)) and / or PBTC (2-phosphonobutane-1,2,4-tricarboxylic acid). These compounds are usually used as corrosion inhibitors and / or serve to keep metal ions in solution. Interestingly, a precipitate could nevertheless form be observed when adding one of the aforementioned compounds to a degreasing solution.
Durch eine bevorzugte Dosierung eines Phosphonsäurederivate kann eine Einstellung des Eisengehaltes in der Lösung des Bades erfolgen, was praktisch zu einer nahezu unbegrenzten Standzeit des Bades führt.A preferred dosage of a phosphonic acid derivative can adjust the iron content in the solution of the bath, which practically leads to an almost unlimited service life of the bath.
Bei dem Phosphonsäurederivat kann es sich um ein Derivat einer einfachen oder komplexen Phosphonsäure handeln.The phosphonic acid derivative can be a derivative of a simple or complex phosphonic acid.
Das zugesetzte Reinigungsmittel weist einen pH-Wert von weniger als 4,0 auf.The detergent added has a pH value of less than 4.0.
Die aus dem Reinigungsmittel hergestellte entfettende Lösung ist zur Entfettung einer Eisen- oder Stahloberfläche bei der Feuerverzinkung oder bei der galvanischen Behandlung von Metalloberflächen verwendet werden.The degreasing solution made from the cleaning agent is used for degreasing an iron or steel surface during hot-dip galvanizing or during the galvanic treatment of metal surfaces.
Die Konzentration an Phosphonsäure oder einem Phosphonsäurederivat in der entfettenden Lösung beträgt bevorzugt 0,0001 bis 50%, insbesondere 0,1 bis 10%, bezogen auf die vorhandene Menge an freier Säure in der entfettenden Lösung. Dabei enthält die entfettende Lösung in jedem Fall zumindest eine Säure.The concentration of phosphonic acid or a phosphonic acid derivative in the degreasing solution is preferably 0.0001 to 50%, in particular 0.1 to 10%, based on the amount of free acid present in the degreasing solution. The degreasing solution always contains at least one acid.
Dabei kann eine Phosphonsäure auch separat einer bereits bestehenden Reinigungslösung zur Metallfällung zugesetzt werden.A phosphonic acid can also be added separately to an existing cleaning solution for metal precipitation.
Vor, während oder nach der Entfettung, also dem Eintauchen der Metalloberfläche in ein saures Bad, kann Phosphonsäure oder ein Phosphonsäurederivat von bevorzugt 0,0001 bis 10%, insbesondere 0,01 bis 1%, bezogen auf die vorhandene Menge an freier Säure, in der entfettenden Lösung zudosiert werden.Before, during or after degreasing, i.e. immersing the metal surface in an acidic bath, phosphonic acid or a phosphonic acid derivative of preferably 0.0001 to 10%, in particular 0.01 to 1%, based on the amount of free acid present, can be added in added to the degreasing solution.
Zusätzlich zur Zugabe der Phosphonsäure oder des Phosphonsäurederivates kann auch eine Mineralsäure und/oder eine organische Säure zugegeben werden, um eine verstärkte Reinigungs- bzw. Niederschlagsbildung zu erreichen. Bevorzugte Mineralsäuren sind dabei Salzsäure, Schwefelsäure, Phosphorsäure und/oder Salpetersäure. Bevorzugte organische Säuren sind Oxalsäure, Weinsäure, Zitronensäure und/oder Essigsäure.In addition to adding the phosphonic acid or the phosphonic acid derivative, a mineral acid and / or an organic acid can also be added in order to achieve increased cleaning or precipitation. Preferred mineral acids are hydrochloric acid, sulfuric acid, phosphoric acid and / or nitric acid. Preferred organic acids are oxalic acid, tartaric acid, citric acid and / or acetic acid.
Die Konzentration der Mineralsäure und/oder organischen Säure in der entfettenden Lösung beträgt vorzugsweise 0,1 bis 90 Gew.-%, bezogen auf das Gesamtgewicht der Lösung.The concentration of the mineral acid and / or organic acid in the degreasing solution is preferably 0.1 to 90% by weight, based on the total weight of the solution.
Zusätzlich enthält die entfettende Lösung Tenside, insbesondere nichtionische, anionische und/oder kationische Tenside, wobei sich ein Anteil an Phosphonsäure oder Phosphonsäurederivat besonders positiv auf die Löslichkeit von nichtionischen Tensiden auswirkt, insbesondere in einer besonders bevorzugten Konzentration von 0,01 bis 10 Gew.-%, insbesondere 0,1-1Gew.% bezogen auf das Gesamtgewicht der entfettenden Lösung.In addition, the degreasing solution contains surfactants, in particular nonionic, anionic and / or cationic surfactants, a proportion of phosphonic acid or phosphonic acid derivative having a particularly positive effect on the solubility of nonionic surfactants, in particular in a particularly preferred concentration of 0.01 to 10 wt. %, in particular 0.1-1% by weight based on the total weight of the degreasing solution.
Unabhängig von der besonders bevorzugten Erhöhung der Wirksamkeit der Tenside in Lösung für die Zugabe an Phosphonsäure oder Phosphonsäurederivat hat der Einsatz von phosphonsäure- oder phosphonsäurederivathaltiger Lösung auch zu einer Erhöhung der Löslichkeit von Fetten und Ölen in einer tensidfreien Lösung, so dass der Einsatz auch bei einer Entfettung von Metallen mit tensidfreien entfettenden Lösungen Vorteile hat. Allerdings ist die entfettende Wirkung einer tensidhaltigen Lösung in Kombination mit einer Phosphonsäure oder einem Phosphonsäurederivat wesentlich höher.Regardless of the particularly preferred increase in the effectiveness of the surfactants in solution for the addition of phosphonic acid or phosphonic acid derivative The use of solutions containing phosphonic acid or phosphonic acid derivatives also increases the solubility of fats and oils in a surfactant-free solution, so that their use also has advantages when degreasing metals with surfactant-free degreasing solutions. However, the degreasing effect of a surfactant-containing solution in combination with a phosphonic acid or a phosphonic acid derivative is significantly higher.
Darüber hinaus kann die entfettende Lösung auch Inhibitoren enthalten, um die Aufnahme von Eisenionen aus den behandelten Metalloberflächen zu minimieren. Inhibitoren vermindern einerseits die Metallaufnahme und reduzieren andererseits die Bildung von Wasserstoff und sollen teilweise auch das Eindiffundieren von Wasserstoff in das Metallgefüge vermindern. Außerdem wird die Standzeit von Beizen erhöht, da der Metallgehalt dann langsamer steigt. Deshalb werden die Inhibitor-haltigen Beizlösungen teilweise auch als Sparbeizen bezeichnet. Die Inhibitoren sind üblicherweise Stoffe, welche die Metalloberfläche mit einem Überzug, teilweise monomolekularen Film überziehen. Bekannte Inhibitoren sind ungesättigte Diole wie z.B. Butindiol bzw. deren Derivate, organische Schwefelverbindungen wie Thioharnstoff bzw. dessen Derivate oder Stickstoff-haltige Verbindungen wie z.B. Hexamethylentetramin oder quarternäre Stickstoffverbindungen oder andere Inhibitoren. Diese legen in einer Konzentration von 0,01 - 1 Gew.-%, bezogen auf das Gesamtgewicht der Lösung vor.In addition, the degreasing solution can also contain inhibitors in order to minimize the absorption of iron ions from the treated metal surfaces. Inhibitors, on the one hand, reduce the uptake of metal and, on the other hand, reduce the formation of hydrogen and, in some cases, are also intended to reduce the diffusion of hydrogen into the metal structure. In addition, the service life of pickling is increased because the metal content then increases more slowly. That is why the inhibitor-containing pickling solutions are sometimes also referred to as economy pickling. The inhibitors are usually substances which cover the metal surface with a coating, sometimes a monomolecular film. Known inhibitors are unsaturated diols such as butynediol or its derivatives, organic sulfur compounds such as thiourea or its derivatives or nitrogen-containing compounds such as hexamethylenetetramine or quaternary nitrogen compounds or other inhibitors. These are present in a concentration of 0.01-1% by weight, based on the total weight of the solution.
Weitere bevorzugte Zusätze der Entfettungslösung sind Lösemittel, Lösevermittler, Stellmittel und/oder Duftstoffe jeweils in einer bevorzugten Konzentration von 0,001 bis 10 Gew.-%, insbesondere in einer Konzentration von 0,01 bis 5 Gew.-%.Further preferred additives to the degreasing solution are solvents, solubilizers, adjusting agents and / or fragrances, each in a preferred concentration of 0.001 to 10% by weight, in particular in a concentration of 0.01 to 5% by weight.
Claims (7)
- Use of a degreasing solution in the degreasing of iron or steel surfaces in hot dipped galvanizing or electroplating, characterized in that the degreasing solution contains a phosphonic acid and/or a phosphonic acid derivative and a surfactant which has a degreasing action, where the degreasing solution comprises a further acid and has a pH of less than 4.0.
- Use according to Claim 1, characterized in that the degreasing solution has a content of phosphonic acid of from 0.0001 to 50%, based on the amount of free acid in the degreasing solution.
- Use according to either of the preceding claims, characterized in that the degreasing solution has a surfactant content of from 0.01 to 10% by weight.
- Use according to any of the preceding claims, characterized in that the degreasing solution additionally contains at least one solvent, an inhibitor, a solubilizer, a suspending agent and/or a fragrance in a concentration of from 0.001 to 10% by weight.
- Use according to any of the preceding claims, characterized in that the concentration of inhibitors in the case of the degreasing solution comprising an inhibitor in order to minimize the uptake of iron ions from the treated metal surfaces which is in the range from 0.01 to 1% by weight, based on the total weight of the solution.
- Process for degreasing an iron or steel surface in hot dipped galvanizing or the electrochemical treatment of the metal surface, characterized by the following steps:a) provision of a surfactant-containing solution having a pH of less than 4.0 for degreasing the metal surfaceb) degreasing of the metal surface by introduction into the surfactant-containing solution; andc) addition of a solution containing a phosphonic acid and/or phosphonic acid derivative and having a pH of less than 4.0 during or after degreasing of the metal surface to the surfactant-containing solution in order to reduce the metal ion content in the solution, where the solution formed comprises one or more further acids in addition to the phosphonic acid or the phosphonic acid derivative.
- Process according to Claim 6, characterized in that the proportion of the phosphonic acid or the phosphonic acid derivative in the solution in step c) is from 0.0001 to 50% by weight, based on the total amount of free acid in the solution used for degreasing or pickling degreasing.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| PL13168021T PL2671972T3 (en) | 2012-06-08 | 2013-05-16 | Use of a solution containing phosphonic acid and/or phosphonic acid derivatives during the degreasing of metal surfaces, degreasing solution and method for degreasing a metal surface |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE102012104951A DE102012104951A1 (en) | 2012-06-08 | 2012-06-08 | Use of a phosphonic acid and / or phosphonic acid derivative-containing solution in the degreasing of metal surfaces, degreasing solution and method for degreasing a metal surface |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| EP2671972A1 EP2671972A1 (en) | 2013-12-11 |
| EP2671972B1 true EP2671972B1 (en) | 2021-05-05 |
Family
ID=48430551
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP13168021.7A Active EP2671972B1 (en) | 2012-06-08 | 2013-05-16 | Use of a solution containing phosphonic acid and/or phosphonic acid derivatives during the degreasing of metal surfaces, degreasing solution and method for degreasing a metal surface |
Country Status (4)
| Country | Link |
|---|---|
| EP (1) | EP2671972B1 (en) |
| DE (1) | DE102012104951A1 (en) |
| ES (1) | ES2871404T3 (en) |
| PL (1) | PL2671972T3 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104862719A (en) * | 2015-03-12 | 2015-08-26 | 浏阳市三鹰新材料有限责任公司 | Environmental-protection type multifunctional efficient acid washing mist inhibition corrosion inhibitor |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0789094A1 (en) * | 1994-10-21 | 1997-08-13 | Nippon Paint Co., Ltd. | Aqueous acid cleaning solution for aluminum metal and method for cleaning the metal |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1216066B (en) * | 1963-01-29 | 1966-05-05 | Henkel & Cie Gmbh | Process for the treatment of degreased metal surfaces stained with an acidic solution before enamelling |
| DE10154922B4 (en) * | 2001-11-08 | 2004-04-01 | Benteler Automobiltechnik Gmbh | Process for cleaning metallic components |
| JP5467996B2 (en) * | 2007-04-04 | 2014-04-09 | ヘンケル・アクチェンゲゼルシャフト・ウント・コムパニー・コマンディットゲゼルシャフト・アウフ・アクチェン | Detergent or detergent containing bleach |
| DE102007042859A1 (en) * | 2007-09-10 | 2009-03-12 | Henkel Ag & Co. Kgaa | cleaning process |
-
2012
- 2012-06-08 DE DE102012104951A patent/DE102012104951A1/en not_active Withdrawn
-
2013
- 2013-05-16 PL PL13168021T patent/PL2671972T3/en unknown
- 2013-05-16 ES ES13168021T patent/ES2871404T3/en active Active
- 2013-05-16 EP EP13168021.7A patent/EP2671972B1/en active Active
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0789094A1 (en) * | 1994-10-21 | 1997-08-13 | Nippon Paint Co., Ltd. | Aqueous acid cleaning solution for aluminum metal and method for cleaning the metal |
Also Published As
| Publication number | Publication date |
|---|---|
| ES2871404T3 (en) | 2021-10-28 |
| PL2671972T3 (en) | 2021-11-02 |
| EP2671972A1 (en) | 2013-12-11 |
| DE102012104951A1 (en) | 2013-12-12 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP2534279B1 (en) | Composition for the alkaline passivation of zinc surfaces | |
| EP2507408B1 (en) | Multi-stage pre-treatment method for metal components having zinc and iron surfaces | |
| EP3158049B1 (en) | Detergent for gentle removal of inks and markers | |
| WO2017202891A1 (en) | Process for corrosion-protecting phosphatization of a metallic surface with reduced pickling erosion | |
| WO2019158508A1 (en) | Process for selective phosphating of a composite metal construction | |
| EP1097255B1 (en) | Process of pre-treating a metallic workpiece before painting | |
| DE69534340T2 (en) | ACID TREATMENT OF STAINLESS STEEL | |
| EP1809791B1 (en) | Method for removing laser scales | |
| EP2215285A1 (en) | Zirconium phosphating of metal components, in particular iron | |
| EP3448938A1 (en) | Method for anti-corrosion treatment of a metal surface with reduced pickling material | |
| EP2671972B1 (en) | Use of a solution containing phosphonic acid and/or phosphonic acid derivatives during the degreasing of metal surfaces, degreasing solution and method for degreasing a metal surface | |
| EP3449040A1 (en) | Composition for reducing the removal of material by pickling in the pickling of metal surfaces that contain galvanized and/or ungalvanized steel | |
| DE102009047523A1 (en) | Multi-stage method for corrosion-inhibiting pretreatment of metallic components having the surfaces of zinc, comprises subjecting the metallic components with an aqueous treatment solution, and cleaning and degreasing the metal surface | |
| US10415140B2 (en) | Two-stage pre-treatment of aluminum comprising pickling and passivation | |
| DE102009028097A1 (en) | Chemically removing workpiece, comprises treating the workpiece to be treated with first aqueous acidic solution of oxidizing compound in first process step, and treating the workpiece resulting from first process step with second solution | |
| EP2956569B1 (en) | Method for coating metallic surfaces for preventing pinholes on zinc-containing metal surfaces | |
| DE3217145A1 (en) | Method for cleaning, degreasing and activating metal surfaces | |
| EP3456864B1 (en) | Two stage pre-treatment of aluminium, in particular aluminium casting alloys, comprising a pickle and a conversion treatment | |
| DE3541997A1 (en) | IMPROVED METHOD FOR ACTIVATING METAL SURFACES BEFORE ZINC PHOSPHATION | |
| WO1992022686A1 (en) | Method of pretreating the surfaces of non-ferrous metals prior to galvanic deposition of a coat of metal | |
| EP3794167B1 (en) | Rack cleaning in a process of electrophoretic coating | |
| DE102008001338A1 (en) | Chemical deburring of workpieces comprises treating workpiece with first aqueous acid solution comprising oxidizing compound, and second solution comprising surface active agent e.g. polyoxyethylene ether and builder compound e.g. silicate | |
| JP3364667B2 (en) | Composition for plating pretreatment | |
| DE2103086A1 (en) | Process for the surface treatment of iron and steel | |
| CN104404546A (en) | Antirust cleaning agent for sensor galvanized shell |
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 |
|
| 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 |
|
| 17P | Request for examination filed |
Effective date: 20140409 |
|
| 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 |
|
| STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE |
|
| R17P | Request for examination filed (corrected) |
Effective date: 20140409 |
|
| RIN1 | Information on inventor provided before grant (corrected) |
Inventor name: NEUHAUS, GUNTER Inventor name: ROTHFELD, SASCHA Inventor name: KADER, JUERGEN |
|
| STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: EXAMINATION IS IN PROGRESS |
|
| 17Q | First examination report despatched |
Effective date: 20180725 |
|
| RIN1 | Information on inventor provided before grant (corrected) |
Inventor name: ROTHFELD, SASCHA Inventor name: NEUHAUS, GUNTER Inventor name: KADER, JUERGEN |
|
| 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: 20201217 |
|
| 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 Free format text: NOT ENGLISH |
|
| REG | Reference to a national code |
Ref country code: CH Ref legal event code: EP Ref country code: CH Ref legal event code: NV Representative=s name: ISLER AND PEDRAZZINI AG, CH |
|
| REG | Reference to a national code |
Ref country code: AT Ref legal event code: REF Ref document number: 1389917 Country of ref document: AT Kind code of ref document: T Effective date: 20210515 |
|
| REG | Reference to a national code |
Ref country code: IE Ref legal event code: FG4D Free format text: LANGUAGE OF EP DOCUMENT: GERMAN |
|
| REG | Reference to a national code |
Ref country code: DE Ref legal event code: R096 Ref document number: 502013015689 Country of ref document: DE |
|
| REG | Reference to a national code |
Ref country code: NL Ref legal event code: FP |
|
| REG | Reference to a national code |
Ref country code: LT Ref legal event code: MG9D |
|
| REG | Reference to a national code |
Ref country code: ES Ref legal event code: FG2A Ref document number: 2871404 Country of ref document: ES Kind code of ref document: T3 Effective date: 20211028 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
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: 20210505 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: 20210805 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: 20210505 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: 20210505 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
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: 20210806 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: 20210505 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: 20210905 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: 20210505 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: 20210505 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: 20210906 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: 20210805 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
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: 20210505 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: 20210505 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: 20210505 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: 20210505 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: 20210505 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: 20210505 Ref country code: LU Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20210516 |
|
| REG | Reference to a national code |
Ref country code: DE Ref legal event code: R097 Ref document number: 502013015689 Country of ref document: DE |
|
| 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: 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: 20210505 |
|
| 26N | No opposition filed |
Effective date: 20220208 |
|
| GBPC | Gb: european patent ceased through non-payment of renewal fee |
Effective date: 20210805 |
|
| 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: 20210516 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
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: 20210905 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: 20210505 |
|
| 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: 20210805 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: HU Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT; INVALID AB INITIO Effective date: 20130516 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
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: 20210505 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: NL Payment date: 20230427 Year of fee payment: 11 Ref country code: IT Payment date: 20230531 Year of fee payment: 11 Ref country code: FR Payment date: 20230427 Year of fee payment: 11 Ref country code: ES Payment date: 20230609 Year of fee payment: 11 Ref country code: DE Payment date: 20230627 Year of fee payment: 11 Ref country code: CH Payment date: 20230602 Year of fee payment: 11 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: PL Payment date: 20230414 Year of fee payment: 11 Ref country code: AT Payment date: 20230427 Year of fee payment: 11 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: BE Payment date: 20230421 Year of fee payment: 11 |
|
| 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: 20210505 |