EP0294687B1 - Use of sulfonamidcarboxylic acid salts as corrosion inhibitors in aqueous systems - Google Patents
Use of sulfonamidcarboxylic acid salts as corrosion inhibitors in aqueous systems Download PDFInfo
- Publication number
- EP0294687B1 EP0294687B1 EP88108665A EP88108665A EP0294687B1 EP 0294687 B1 EP0294687 B1 EP 0294687B1 EP 88108665 A EP88108665 A EP 88108665A EP 88108665 A EP88108665 A EP 88108665A EP 0294687 B1 EP0294687 B1 EP 0294687B1
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- EP
- European Patent Office
- Prior art keywords
- formula
- corrosion
- aqueous systems
- phenyl
- compound
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Classifications
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- 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
- C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
- C23F11/00—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent
- C23F11/08—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent in other liquids
- C23F11/10—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent in other liquids using organic inhibitors
- C23F11/16—Sulfur-containing compounds
- C23F11/164—Sulfur-containing compounds containing a -SO2-N group
Definitions
- the invention relates to the use of special sulfonamidocarboxylic acids in the form of the alkali or alkanolamine salts as corrosion inhibitors in aqueous systems.
- DE-A1-33 30 223 describes the salts of the reaction products of alkylbenzenesulfonyl chlorides with glycine or methylglycine as corrosion inhibitors in aqueous systems.
- the properties of the sulfonamido carboxylic acids described above as corrosion inhibitors are not always optimal.
- the actual corrosion protection effect is often too low, so that relatively large amounts have to be used.
- the foaming is too high and the water solubility and water hardness sensitivity, which are of considerable importance, may leave something to be desired.
- the toxicity of the substances used can also play an important role.
- the aim of the present invention is, in particular, to show substances which, in addition to low toxicity in aqueous systems, in addition to good corrosion protection, ensure low foam and low sensitivity to water hardness.
- R1 and R2 represent a phenyl radical which may be mono- or disubstituted by an alkyl radical having 1 to 6 carbon atoms and represent n 0, 1 or 2 and m 1 or 2, in the form of an alkali or an alkanolamine salt in an amount of 0.1 to 2% by weight, based on the aqueous system.
- the invention also relates to a method for preventing corrosion in aqueous systems by adding a compound of the formula I in the form of an alkali or alkanolamine salt in the abovementioned amount to the aqueous system as a corrosion inhibitor.
- the salts of the formula I can also be used in the form of their mixtures.
- Alkyl radicals with 1 to 6 carbon atoms, through which the phenyl radicals can be mono- or disubstituted, are, for example, methyl, ethyl, propyl, i-propyl, butyl, pentyl, hexyl.
- the higher alkyl residues with 3 to 6 carbon atoms are particularly suitable for simple substitution.
- R 1 and R 2 are phenyl or tolyl and n is 0 and m is 1 or 2.
- Preferred tolyl radicals are the o- and p-tolyl radicals.
- the alkali metal salts are the sodium and potassium salts and the alkanolammonium salts are the salts of mono-, di- or tri-hydroxyalkylamines having 2 to 4 carbon atoms in the hydroxyalkyl radical and mono- (C2-C4) - hydroxyalkyl-mono- or -dialkylamines having 1 to 4 carbon atoms in the alkyl radical and di- (C2-C4) -hydroxyalkyl-mono- (C1-C4) alkylamines.
- Preferred alkanolamines are mono-, di- and triethanolamine, mono-, di- and trihydroxyisopropylamine as well as N-methyldiethanolamine and dimethyl-monoethanolamine.
- they are also their mixtures, as are obtained in industrial production.
- the acids of the formula I are known in principle from the literature and can be prepared by processes known per se.
- the use of their alkanolamine salts as corrosion inhibitors is by no means apparent from the literature.
- the acids of formula I are conveniently with the above.
- the sulfonamide nitrogen atom has a hydrogen atom or an alkyl radical, preferably methyl, as a substituent.
- the compounds of the formula I to be used according to the invention have an aromatic radical or aromatic substituted alkyl radical on the nitrogen atom corresponding to the meanings of R 1 and n.
- the present invention makes the sulfonamido carboxylic acids substituted by aromatic radicals technically usable for the first time. Since corrosion inhibition and foaming behavior are very sensitive and unpredictable properties, the superior effects are not obvious despite the relatively small structural differences.
- the corrosion inhibitors according to the invention can be used in all aqueous systems which come into contact with iron, its alloys (steels), aluminum, its alloys, zinc or copper and their alloys.
- aqueous systems which come into contact with iron, its alloys (steels), aluminum, its alloys, zinc or copper and their alloys.
- Examples include Hydraulic fluids, cooling lubricants, neutral to alkaline technical cleaners, cooling water additives, coolant or pit water, which are particularly hard and salt-rich and which are used directly in mining as mixing water e.g. used for hydraulic processes and which have a particularly strong corrosive effect.
- the aqueous systems have a suitable pH range from 8.0 to 8.8.
- concentrations in practical use fluctuate depending on the area of application and the type of aqueous medium and the metals to be protected. In general, 0.1 to 2% by weight, based on the aqueous system, is used. Falling below this limit generally reduces the protective effect, exceeding this does not result in any additional advantages.
- the corrosion protection effect is determined in accordance with DIN Test 51360, Part 2.
- the sulfonamidocarboxylic acid to be investigated is mixed with such an amount of triethanolamine (TEA) that a 1% by weight aqueous solution has a pH of 8.2 ⁇ 0.1.
- TAA triethanolamine
- Table 2 shows the results obtained, which contain a comparison with N-methyl-benzenesulfonamidocaproic acid (commercially available).
Description
Die Erfindung betrifft die Verwendung spezieller Sulfonamidocarbonsäuren in Form der Alkali- oder Alkanolaminsalze als Korrosionsinhibitoren in wäßrigen Systemen.The invention relates to the use of special sulfonamidocarboxylic acids in the form of the alkali or alkanolamine salts as corrosion inhibitors in aqueous systems.
In technischen Prozessen, beispielsweise Reinigungs-, Druckübertragungs- und Kühlprozessen, die sich in Gegenwart von Wasser abspielen, stellt sich immer das Problem des Korrosionsschutzes, wenn korrosionsgefährdete Metalle, wie Kupfer, Eisen, Aluminium oder deren Legierungen oder z.B. Weichlot, durch diese Prozesse betroffen werden. Für die Zwecke des Korrosionsschutzes wurden in letzter Zeit zahlreiche Inhibitoren vorgeschlagen, vor allem organische Verbindungen, wie Acylsarkoside, Amine, Alkanolamine, Amide langkettiger Fettsäuren und auch bestimmte Sulfonamidocarbonsäuren [vgl. z.B. Seifen, Öle, Fette, Wachse, 130, Heft 6, 167 bis 168, 1979].In technical processes, for example cleaning, pressure transmission and cooling processes that take place in the presence of water, the problem of corrosion protection always arises when metals at risk of corrosion, such as copper, iron, aluminum or their alloys or e.g. Soft solder, affected by these processes. For the purpose of corrosion protection, numerous inhibitors have recently been proposed, especially organic compounds, such as acyl sarcosides, amines, alkanolamines, amides of long-chain fatty acids and also certain sulfonamido carboxylic acids [cf. e.g. Soaps, Oils, Fats, Waxes, 130, Issue 6, 167 to 168, 1979].
Weiterhin ist beispielsweise aus der DE-PS 12 98 672 bekannt, daß die Umsetzungsprodukte von aliphatischen ω-Aminosäuren mit mehr als 3 C-Atomen in der Carboxylseitenkette mit aromatischen Sulfonsäurechloriden, insbesondere in Form der Triethanolaminsalze, als Korrosionsschutzmittel verwendet werden können.Furthermore, it is known, for example from DE-PS 12 98 672, that the reaction products of aliphatic ω-amino acids with more than 3 C atoms in the carboxyl side chain with aromatic sulfonic acid chlorides, in particular in the form of the triethanolamine salts, can be used as corrosion inhibitors.
Ebenso werden in der DE-A1-33 30 223 die Salze der Umsetzungsprodukte von Alkylbenzolsulfonsäurechloriden mit Glycin oder Methylglycin als Korrosionsinhibitoren in wäßrigen Systemen beschrieben.Likewise, DE-A1-33 30 223 describes the salts of the reaction products of alkylbenzenesulfonyl chlorides with glycine or methylglycine as corrosion inhibitors in aqueous systems.
Die Eigenschaften der oben beschriebenen Sulfonamidocarbonsäuren als Korrosionsinhibitoren sind nicht immer optimal. Häufig ist die eigentliche Korrosionsschutzwirkung zu niedrig, so daß reltive große Mengen verwendet werden müssen. Teilweise ist die Schaumbildung zu hoch und die Wasserlöslichkeit und Wasserhärteempfindlichkeit, die von erheblicher Bedeutung sind, können unter Umständen zu wünschen übrig lassen. Auch die Toxizität der verwendeten Substanzen kann eine wesentliche Rolle spielen.The properties of the sulfonamido carboxylic acids described above as corrosion inhibitors are not always optimal. The actual corrosion protection effect is often too low, so that relatively large amounts have to be used. In some cases, the foaming is too high and the water solubility and water hardness sensitivity, which are of considerable importance, may leave something to be desired. The toxicity of the substances used can also play an important role.
Das Ziel der vorliegenden Erfindung besteht insbesondere darin, Stoffe aufzuzeigen, die neben geringer Toxizität in wäßrigen Systemen neben einem guten Korrosionsschutz Schaumarmut und niedrige Wasserhärteempfindlichkeit optimal gewährleisten.The aim of the present invention is, in particular, to show substances which, in addition to low toxicity in aqueous systems, in addition to good corrosion protection, ensure low foam and low sensitivity to water hardness.
Es wurde nun gefunden, daß man überraschenderweise zu ausgezeichneten Ergebnissen gelangt, wenn man als Korrosionsinhibitoren in wäßrigen Systemen eine Verbindung der Formel I
in der R¹ und R² einen Phenylrest, der ggfs. ein- oder zweifach durch einen Alkylrest mit 1 bis 6 C-Atomen substituiert ist, bedeuten und für n 0, 1 oder 2 und für m 1 oder 2 stehen, in Form eines Alkali- oder eines Alkanolaminsalzes in einer Menge von 0,1 bis 2 Gew.%, bezogen auf das wäßrige System, verwendet.It has now been found that, surprisingly, excellent results are obtained if a compound of the formula I is used as the corrosion inhibitor in aqueous systems
in which R¹ and R² represent a phenyl radical which may be mono- or disubstituted by an alkyl radical having 1 to 6 carbon atoms and represent n 0, 1 or 2 and m 1 or 2, in the form of an alkali or an alkanolamine salt in an amount of 0.1 to 2% by weight, based on the aqueous system.
Gegenstand der Erfindung ist auch ein Verfahren zur Verhinderung von Korrosion in wäßrigen Systemen, indem man dem wäßrigen System als Korrosionsinhibitor eine Verbindung der Formel I in Form eines Akali- oder Alkanolaminsalzes in der oben genannten Menge zusetzt.The invention also relates to a method for preventing corrosion in aqueous systems by adding a compound of the formula I in the form of an alkali or alkanolamine salt in the abovementioned amount to the aqueous system as a corrosion inhibitor.
Dabei können die Salze der Formel I auch in Form ihrer Mischungen verwendet werden.The salts of the formula I can also be used in the form of their mixtures.
Alkylreste mit 1 bis 6 C-Atomen, durch die die Phenylreste ein- oder zweifach substituiert sein können, sind beispielsweise Methyl, Ethyl, Propyl, i-Propyl, Butyl, Pentyl, Hexyl. Die höheren Akylreste mit 3 bis 6 C-Atomen kommen insbesondere bei einer einfachen Substitution in Betracht.Alkyl radicals with 1 to 6 carbon atoms, through which the phenyl radicals can be mono- or disubstituted, are, for example, methyl, ethyl, propyl, i-propyl, butyl, pentyl, hexyl. The higher alkyl residues with 3 to 6 carbon atoms are particularly suitable for simple substitution.
Von den Verbindungen der Formel I sind solche hervorzuheben, bei denen für R¹ und R² Phenyl oder Tolyl steht und n 0 und m 1 oder 2 bedeuten. Als Tolylreste kommen dabei bevorzugt der o- und p-Tolylrest in Betracht.Of the compounds of the formula I, those are to be emphasized in which R 1 and R 2 are phenyl or tolyl and n is 0 and m is 1 or 2. Preferred tolyl radicals are the o- and p-tolyl radicals.
Für die erfindungsgemäß in wäßrigen Systemen zu verwendenden Verbindungen kommen als Alkalisalze die Natrium- und Kaliumsalze und als Alkanolammoniumsalze die Salze von Mono-, Di- oder Tri-hydroxyalkylaminen mit 2 bis 4 C-Atomen im Hydroxyalkylrest sowie Mono-(C₂-C₄)-hydroxyalkyl-mono- oder -dialkylamine mit 1 bis 4 C-Atomen im Alkylrest und Di-(C₂-C₄)-hydroxyalkyl-mono-(C₁-C₄)-alkylamine in Betracht.For the compounds to be used according to the invention in aqueous systems, the alkali metal salts are the sodium and potassium salts and the alkanolammonium salts are the salts of mono-, di- or tri-hydroxyalkylamines having 2 to 4 carbon atoms in the hydroxyalkyl radical and mono- (C₂-C₄) - hydroxyalkyl-mono- or -dialkylamines having 1 to 4 carbon atoms in the alkyl radical and di- (C₂-C₄) -hydroxyalkyl-mono- (C₁-C₄) alkylamines.
Bevorzugte Alkanolamine sind Mono-, Di- und Triethanolamin, Mono-, Di- und Trihydroxyisopropylamin sowie N-Methyldiethanolamin und Dimethyl-mono- ethanolamin. In der Praxis handelt es sich neben den reinen Alkanolaminen auch um ihre Gemische, wie sie bei der technischen Herstellung anfallen.Preferred alkanolamines are mono-, di- and triethanolamine, mono-, di- and trihydroxyisopropylamine as well as N-methyldiethanolamine and dimethyl-monoethanolamine. In practice, in addition to the pure alkanolamines, they are also their mixtures, as are obtained in industrial production.
Die Säuren der Formel I sind grundsätzlich aus der Literatur bekannt und können nach an sich bekannten Verfahren hergestellt werden. Eine Verwendung ihrer Alkanolaminsalze als Korrosionsschutzmittel geht keinesfalls aus der Literatur hervor.The acids of the formula I are known in principle from the literature and can be prepared by processes known per se. The use of their alkanolamine salts as corrosion inhibitors is by no means apparent from the literature.
Die Säuren der Formel I werden zweckmäßigerweise mit den o.g. Alkanolaminen im Molverhältnis 1:1 bis 1:4 in das entsprechende Salz überführt. Aus praktischen Gründen, um bei der Anwendung zweckmäßige pH-Bereiche von 8,0 bis 8,8 zu erhalten, werden meist überschüssige Mengen Alkanolamin verwendet.The acids of formula I are conveniently with the above. Alkanolamines in a molar ratio of 1: 1 to 1: 4 converted into the corresponding salt. Excess amounts of alkanolamine are usually used for practical reasons in order to obtain suitable pH ranges from 8.0 to 8.8.
Bei den im Stand der Technik beschriebenen Verbindungen weist das Sulfonamidstickstoffatom ein Wasserstoffatom oder einen Alkylrest, bevorzugt Methyl, als Substituenten auf. Die erfindugsgemäß zu verwendenden Verbindungen der Formel I tragen entsprechend den Bedeutungen von R¹ und n einen aromatischen Rest oder aromatischen substituierten Alkylrest am Stickstoffatom. Durch die vorliegende Erfindung werden die durch aromatische Reste substituierte Sulfonamidocarbonsäuren erstmals technisch nutzbar gemacht. Da Korrosionsinhibierung und Schaumverhalten sehr sensible und nicht voraussagbare Eigenschaften sind, haben trotz relativ geringer struktureller Unterschiede die überlegenen Wirkungen nicht nahegelegen.In the compounds described in the prior art, the sulfonamide nitrogen atom has a hydrogen atom or an alkyl radical, preferably methyl, as a substituent. The compounds of the formula I to be used according to the invention have an aromatic radical or aromatic substituted alkyl radical on the nitrogen atom corresponding to the meanings of R 1 and n. The present invention makes the sulfonamido carboxylic acids substituted by aromatic radicals technically usable for the first time. Since corrosion inhibition and foaming behavior are very sensitive and unpredictable properties, the superior effects are not obvious despite the relatively small structural differences.
Die erfindungsgemäßen Korrosionsinhibitoren können in allen wäßrigen Systemen eingesetzt werden, die mit Eisen, dessen Legierungen (Stählen), Aluminium, dessen Legierungen, Zink oder Kupfer und deren Legierungen in Berührung kommen. Zu nennen sind z.B. Hydraulikflüssigkeiten, Kühlschmierstoffe, neutrale bis alkalische technische Reiniger, Kühlwasserzusätze, Kühlerschutzmittel oder auch Grubenwässer, die besonders hart und salzreich sind und die im Bergbau direkt als Anmischwasser z.B. für hydraulische Prozesse verwendet werden und die besonders stark korrosiv wirken. Die wäßrigen Systeme weisen einen zweckmäßigen pH-Bereich von 8,0 bis 8,8 auf.The corrosion inhibitors according to the invention can be used in all aqueous systems which come into contact with iron, its alloys (steels), aluminum, its alloys, zinc or copper and their alloys. Examples include Hydraulic fluids, cooling lubricants, neutral to alkaline technical cleaners, cooling water additives, coolant or pit water, which are particularly hard and salt-rich and which are used directly in mining as mixing water e.g. used for hydraulic processes and which have a particularly strong corrosive effect. The aqueous systems have a suitable pH range from 8.0 to 8.8.
Die Konzentrationen bei der praktischen Anwendung schwanken je nach Anwendungsbereich und Art des wäßrigen Mediums sowie der zu schützenden Metalle. Im allgemeinen setzt man - bezogen auf das wäßrige System - 0,1 bis 2 Gew.% ein. Eine Unterschreitung dieser Grenze setzt in der Regel die Schutzwirkung herab, eine Überschreitung bewirkt keine zusätzlichen Vorteile.The concentrations in practical use fluctuate depending on the area of application and the type of aqueous medium and the metals to be protected. In general, 0.1 to 2% by weight, based on the aqueous system, is used. Falling below this limit generally reduces the protective effect, exceeding this does not result in any additional advantages.
Im übrigen können bei der Herstellung der üblichen Formulierungen die üblichen Zusätze verwendet werden.Otherwise, the usual additives can be used in the preparation of the customary formulations.
Die nun folgenden Beispiele (Tab 1) erläutern die Erfindung, ohne daß der Anmeldungsgegenstand hierauf beschränkt wäre.
Die Bestimmung der Korrosionsschutzwirkung wird nach dem DIN Test 51360, Teil 2, vorgenommen. Die zu untersuchende Sulfonamidocarbonsäure wird mit einer solchen Menge Triethanolamin (TEA) gemischt, daß eine 1 gew.%ige wäßrige Lösung einen pH-Wert von 8,2 ± 0,1 aufweist.The corrosion protection effect is determined in accordance with DIN Test 51360, Part 2. The sulfonamidocarboxylic acid to be investigated is mixed with such an amount of triethanolamine (TEA) that a 1% by weight aqueous solution has a pH of 8.2 ± 0.1.
Von dieser Mischung werden 2 und zum Vergleich 3 gew.%ige Lösungen mit einer bestimmten Wasserhärte gemäß der DIN-Vorschrift verwendet.Of this mixture, 2 and, for comparison, 3% by weight solutions with a certain water hardness are used in accordance with the DIN specification.
In Tabelle 2 werden die erhaltenen Ergebnisse, die einen Vergleich mit N-Methyl-benzolsulfonamidocapronsäure (handelsüblich) enthalten, angegeben.Table 2 shows the results obtained, which contain a comparison with N-methyl-benzenesulfonamidocaproic acid (commercially available).
Die Bewertungsskala lautet folgendermaßen:
- 4
- = sehr starke Korrosion
- 3
- = starke Korrosion
- 2
- = mäßige Korrosion
- 1
- = geringe Korrosion
- 0
- = keine Korrosion
- 4th
- = very strong corrosion
- 3rd
- = severe corrosion
- 2nd
- = moderate corrosion
- 1
- = low corrosion
- 0
- = no corrosion
Die Ergebnisse zeigen, daß bereits mit 2 gew.%igen Lösungen eine überlegene Korrosionsinhibierung gegenüber der im Handel befindlichen Verbindung erreicht wird.The results show that a superior corrosion inhibition compared to the commercially available compound is achieved with only 2% by weight solutions.
Claims (6)
- The use of a compound of the formula I
- The use as claimed in claim 1 of a compound of the formula I in which R¹ and R² are each phenyl or tolyl, n is 0 and m is 1 or 2.
- The use of a compound of the formula I as claimed in claim 1 or 2 as a corrosion inhibitor for iron, aluminum, zinc, copper or their alloys in aqueous systems having a pH of from 8.0 to 8.8.
- A method for preventing corrosion in aqueous systems, which comprises adding a compound of the formula I
- A method as claimed in claim 4, wherein there is added to the aqueous a compound of the formula I as defined in claim 1 in which R¹ and R² are each phenyl or tolyl, n is 0 and m is 1 or 2.
- A method as claimed in claim 4 or 5, wherein the compound of the formula I is added to the aqueous system as a corrosion inhibitor for iron, aluminum, zinc, copper or their alloys at a pH of from 8.0 to 8.8.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19873719046 DE3719046A1 (en) | 1987-06-06 | 1987-06-06 | USE OF SALTS OF SULFONAMIDE CARBONIC ACIDS AS CORROSION INHIBITORS IN AQUEOUS SYSTEMS |
| DE3719046 | 1987-06-06 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| EP0294687A1 EP0294687A1 (en) | 1988-12-14 |
| EP0294687B1 true EP0294687B1 (en) | 1993-09-22 |
Family
ID=6329231
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP88108665A Expired - Lifetime EP0294687B1 (en) | 1987-06-06 | 1988-05-31 | Use of sulfonamidcarboxylic acid salts as corrosion inhibitors in aqueous systems |
Country Status (4)
| Country | Link |
|---|---|
| US (1) | US4911888A (en) |
| EP (1) | EP0294687B1 (en) |
| JP (1) | JPS6415385A (en) |
| DE (2) | DE3719046A1 (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TW517067B (en) * | 1996-05-31 | 2003-01-11 | Hoffmann La Roche | Interferon conjugates |
| UA59384C2 (en) * | 1996-12-20 | 2003-09-15 | Пфайзер, Інк. | Preventing bone mass loss and recovery thereof by means of prostaglandin agonists |
| UA67754C2 (en) | 1997-10-10 | 2004-07-15 | Пфайзер, Інк. | Prostaglandin agonists and use thereof for the treatment of bone disorders |
| IL139786A0 (en) * | 1998-06-08 | 2002-02-10 | Hoffmann La Roche | Use of peg-ifn-alpha and ribavirin for the treatment of chronic hepatitis c |
| DE102008064004B4 (en) * | 2008-12-19 | 2011-11-24 | Clariant International Limited | Water-based hydraulic fluids containing dithiodi (arylcarboxylic acids) or their alkali metal, alkaline earth metal or ammonium salts |
| US20240093043A1 (en) | 2021-01-25 | 2024-03-21 | Omya International Ag | Coatings comprising surface-reacted calcium carbonate and an oxygen scavenger for improving food shelf life |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE895122C (en) * | 1939-10-21 | 1953-10-29 | Hydrierwerke A G Deutsche | Process for reducing the corrosive influence of water and aqueous solutions on iron |
| GB810560A (en) * | 1954-10-21 | 1959-03-18 | Geigy Ag J R | Improvements relating to alkylarylsulphonyl derivatives of amino acids, to corrosion and rust inhibiting compositions thereof and their use |
| DE1298672B (en) * | 1967-07-15 | 1969-07-03 | Hoechst Ag | Corrosion-preventing metalworking agent |
| BE810115A (en) * | 1973-10-30 | 1974-05-16 | CORROSION INHIBITION METHOD USING CULFONYL GLYCINE COMPOUNDS | |
| CH629540A5 (en) * | 1977-09-19 | 1982-04-30 | Hoechst Ag | WATER-MIXABLE ANTI-CORROSIVE AGENT. |
| DE2947418A1 (en) * | 1979-11-24 | 1981-06-04 | BASF Corp., New York, N.Y. | IMPLEMENTATION PRODUCTS OF SULPHONE OR CARBONAMIDOCARBONIC ACIDS WITH ALKANOLAMINES AND THEIR USE AS LOW-FOAM CORROSION INHIBITORS |
| FR2479844A1 (en) * | 1980-04-04 | 1981-10-09 | Martin Philippe | Water-insol. alkyl-sulphonamido-carboxylate - as anticorrosive agent for metals, esp. automobile bodies and chassis |
| DE3330223A1 (en) * | 1983-08-22 | 1985-03-14 | Henkel KGaA, 4000 Düsseldorf | CORROSION INHIBITORS |
-
1987
- 1987-06-06 DE DE19873719046 patent/DE3719046A1/en not_active Withdrawn
-
1988
- 1988-05-31 DE DE88108665T patent/DE3884277D1/en not_active Expired - Lifetime
- 1988-05-31 EP EP88108665A patent/EP0294687B1/en not_active Expired - Lifetime
- 1988-06-06 US US07/202,244 patent/US4911888A/en not_active Expired - Fee Related
- 1988-06-06 JP JP63137612A patent/JPS6415385A/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| DE3719046A1 (en) | 1988-12-15 |
| DE3884277D1 (en) | 1993-10-28 |
| US4911888A (en) | 1990-03-27 |
| JPS6415385A (en) | 1989-01-19 |
| EP0294687A1 (en) | 1988-12-14 |
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