EP0022999B1 - Corrosion inhibiting composition for aluminium and aluminium alloys - Google Patents

Corrosion inhibiting composition for aluminium and aluminium alloys Download PDF

Info

Publication number
EP0022999B1
EP0022999B1 EP80104040A EP80104040A EP0022999B1 EP 0022999 B1 EP0022999 B1 EP 0022999B1 EP 80104040 A EP80104040 A EP 80104040A EP 80104040 A EP80104040 A EP 80104040A EP 0022999 B1 EP0022999 B1 EP 0022999B1
Authority
EP
European Patent Office
Prior art keywords
weight
component
aluminium
corrosion
alloys
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP80104040A
Other languages
German (de)
French (fr)
Other versions
EP0022999A1 (en
Inventor
Rainer Dr. Helwerth
Horst Lorke
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hoechst AG
Original Assignee
Hoechst AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hoechst AG filed Critical Hoechst AG
Publication of EP0022999A1 publication Critical patent/EP0022999A1/en
Application granted granted Critical
Publication of EP0022999B1 publication Critical patent/EP0022999B1/en
Expired legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • 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

Definitions

  • Component A of the anticorrosive agent according to the invention essentially consists of compounds of the formula in which R is a saturated aliphatic or cyclic hydrocarbon radical or an alkylaryl group with a total of 12-24, preferably 13-16 carbon atoms, R i is hydrogen or CH 3 , R 2 is hydrogen, C 1 -C 3 -alkyl or -hydroxyalkyl, X is an integer from 0 to 9, Y means an equivalent of an alkaline earth metal or zinc cation.
  • a paraffinic hydrocarbon with approximately the following composition can be considered as component B:
  • Component C contains the amine salt of an organic acid consisting, for example, of caprylamine, octylamine, dibutylamine or isodecylamine and caproic acid, caprylic acid and 2-ethylhexane carboxylic acid or isononanoic acid.
  • the equivalence ratio of amine to acid can be between 70:30 to 30:70.
  • Component D is, for example, the reaction product of nonyl or tributylphenol with 2-4 moles of ethylene oxide.
  • Component E is to be understood as a solvent which consists of a linear or branched C 4 -C 8 aliphatic alcohol.
  • anti-corrosion agents are applied by simply spraying them onto the metal parts to be treated.
  • the respective amounts for components A to E are within the The limits specified are chosen so that the total amount for the anti-corrosion agent according to the invention is 100%.
  • the advantageous anticorrosive properties of the anticorrosive agents according to the invention can be seen in the test tests described below.
  • the tests essentially consist of spraying dry, freshly pickled aluminum sheets with the respective corrosion protection agents and observing them for corrosion under the conditions of the Kesternich test (DIN 50 017) for up to 4 weeks.
  • the tendency to corrode was also tested on aluminum sheets which, after being sprayed with the anticorrosive agent, were subjected to a tempering anneal of 180 ° C. for 4 hours.
  • the scores 0-4 are based on the following scheme:
  • the anti-corrosion agents 1 and 2 are according to the invention and the agents 3-5 have been used for this purpose.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Preventing Corrosion Or Incrustation Of Metals (AREA)

Description

Durch die hohe Reaktivität frisch hergestellter Aluminium-Oberflächen tritt bei der Profilherstellung, d. h. dem Strangpressen von AI-Bauteilen (Fensterrahmen, Fassadenverkleidungen u. ä.) das Problem der sogenannten »Vorkorrosion« auf. Hierunter versteht man aspektschädigende Oberflächenschäden, die durch Handschweiß, Wasser bzw. Feuchtigkeit, Verpackungsmaterial und aggressive Industrieatmosphäre noch vor dem Eloxieren auftreten und häufig eine kostenaufwendige manuelle Nachbehandlung der Fertigteile erforderlich machen. An Korrosionsschutzmittel für die Verhinderung dieser Schäden wird gleichzeitig die Forderung nach einer Stabilität bis 180°C (Anlaß-Glühe) und unproblematisches Verhalten in abschließendem Eloxal-Prozeß gestellt. Die bisher im Gebrauch befindlichen Produkte erfüllen die Forderungen nur unvollkommen. Dies gilt auch für das in der FR-A-1 592 566 beschriebene Korrosionsschutzmittel, das ganz allgemein auch zum Schutz vor Korrosion bei Aluminium eingesetzt werden kann. Gegenüber diesem vorbekannten Korrosionsschutzmittel wurde nun gefunden, daß man mit der im folgenden beschriebenen Kombination von Produkten ganz speziell frische Aluminiumoberflächen vor Korrosion schützen kann.Due to the high reactivity of freshly manufactured aluminum surfaces occurs during profile production, i. H. the extrusion of AI components (window frames, facade claddings, etc.) the problem of so-called »pre-corrosion«. This refers to surface damage that damages aspects, which occurs due to hand sweat, water or moisture, packaging material and aggressive industrial atmosphere before anodizing and often necessitates costly manual post-treatment of the finished parts. Corrosion protection agents for preventing this damage are simultaneously called for stability up to 180 ° C (annealing heat) and unproblematic behavior in the final anodizing process. The products previously in use only incompletely meet the requirements. This also applies to the corrosion protection agent described in FR-A-1 592 566, which can also be used in general to protect against corrosion in aluminum. Compared to this previously known corrosion protection agent, it has now been found that the combination of products described below can be used to protect very fresh aluminum surfaces from corrosion.

Gegenstand der Erfindung ist ein verbessertes Korrosionsschutzmittel für Aluminium und dessen Legierungen, bestehend aus:

  • A) 15-50, vorzugsweise 40-50 Gew.-% eines Umsetzungsproduktes, erhalten durch Umsetzung von Sulfochlorierungsprodukten aliphatischer, alkylaromatischer oder cycloaliphatischer Kohlenwasserstoffe mit 12-24 C-Atomen mit Ammoniak oder einem Ci-C3-Alkyl- oder Hydroxyalkylamin, anschließende Umsetzung mit einer C2-C11-Halogencarbonsäure und Überführung in das Erdalkalimetall- oder Zinksalz,
  • B) mindestens 40, vorzugsweise 40-50 Gew.-% eines paraffinischen Kohlenwasserstoffs mit einer Viskosität von 3 bis 5°E/20°C, dessen Gehalt an C13-C16-Paraffin 50-60%, an Naphthenen 50-40% und an Aromaten 0-1% beträgt,
  • C) 1-4, vorzugsweise 1-2 Gew.-% des Salzes aus einem C8-C10-Alkylamin und einer Cs - Cio-Carbonsäure,
  • D) 1-4, vorzugsweise 1-2 Gew.-% eines Oxethylats aus 1 Mol C8-C12-Alkylphenol und 2-10 Mol Ethylenoxid und
  • E) 1-2% eines C4-C8 aliphatischen Alkohols.
The invention relates to an improved corrosion protection agent for aluminum and its alloys, consisting of:
  • A) 15-50, preferably 40-50% by weight of a reaction product obtained by reacting sulfochlorination products of aliphatic, alkylaromatic or cycloaliphatic hydrocarbons having 12-24 carbon atoms with ammonia or a C i -C 3 alkyl or hydroxyalkylamine, subsequent reaction with a C 2 -C 11 halocarboxylic acid and conversion into the alkaline earth metal or zinc salt,
  • B) at least 40, preferably 40-50 wt .-% of a paraffinic hydrocarbon with a viscosity of 3 to 5 ° E / 20 ° C, the content of C 13 -C 16 paraffin 50-60%, and naphthenes 50-40 % and 0-1% of aromatics,
  • C) 1-4, preferably 1-2% by weight of the salt from a C 8 -C 10 alkylamine and a Cs-Cio-carboxylic acid,
  • D) 1-4, preferably 1-2% by weight of an oxyethylate from 1 mol of C 8 -C 12 alkylphenol and 2-10 mol of ethylene oxide and
  • E) 1-2% of a C 4 -C 8 aliphatic alcohol.

Die Komponente A des erfindungsgemäßen Korrosionsschutzmittels besteht im wesentlichen aus Verbindungen der Formel

Figure imgb0001
in der R einen gesättigten aliphatischen oder cyclischen Kohlenwasserstoffrest oder eine Alkylarylgruppe mit insgesamt 12-24, vorzugsweise 13-16 Kohlenstoffatomen, Ri Wasserstoff oder CH3, R2 Wasserstoff, C1-C3-Alkyl oder -Hydroxyalkyl, X eine ganze Zahl von 0 bis 9, Y ein Äquivalent eines Erdalkalimetalls oder Zinkkations bedeutet.Component A of the anticorrosive agent according to the invention essentially consists of compounds of the formula
Figure imgb0001
 in which R is a saturated aliphatic or cyclic hydrocarbon radical or an alkylaryl group with a total of 12-24, preferably 13-16 carbon atoms, R i is hydrogen or CH 3 , R 2 is hydrogen, C 1 -C 3 -alkyl or -hydroxyalkyl, X is an integer from 0 to 9, Y means an equivalent of an alkaline earth metal or zinc cation.

Die Herstellung dieser Umsetzungsprodukte, ausgehend von den Sulfochlorierungsprodukten gesättigter nichtaromatischer Kohlenwasserstoffe, kann z. B. nach dem Verfahren der deutschen Patentschrift 767 071 erfolgen.The preparation of these reaction products, starting from the sulfochlorination products of saturated non-aromatic hydrocarbons, can, for. B. by the method of German Patent 767 071.

Als Komponente B kommt ein paraffinischer Kohlenwasserstoff mit etwa folgender Zusammensetzung in Betracht:

Figure imgb0002
A paraffinic hydrocarbon with approximately the following composition can be considered as component B:
Figure imgb0002

Die Komponente C enthält das Aminsalz einer organischen Säure, bestehend beispielsweise aus Caprylamin, Octylamin, Dibutylamin oder Isodecylamin und Capronsäure, Caprylsäure und 2-Ethylhexancarbonsäure oder Isononansäure. Das Äquivalenzverhältnis von Amin zu Säure kann zwischen 70 : 30 bis 30 : 70 liegen.Component C contains the amine salt of an organic acid consisting, for example, of caprylamine, octylamine, dibutylamine or isodecylamine and caproic acid, caprylic acid and 2-ethylhexane carboxylic acid or isononanoic acid. The equivalence ratio of amine to acid can be between 70:30 to 30:70.

Die Komponente D ist beispielsweise das Umsetzungsprodukt von Nonyl- oder Tributylphenol mit 2-4 Molen Ethylenoxid.Component D is, for example, the reaction product of nonyl or tributylphenol with 2-4 moles of ethylene oxide.

Unter der Komponente E ist ein Lösungsmittel zu verstehen, das aus einem linearen oder verzweigten C4-C8-aliphatischen Alkohol besteht.Component E is to be understood as a solvent which consists of a linear or branched C 4 -C 8 aliphatic alcohol.

Die Applikation dieser Korrosionsschutzmittel erfolgt durch einfaches Aufsprühen auf die zu behandelnden Metallteile. Die jeweiligen Mengen für die Komponenten A bis E werden innerhalb der jeweils angegebenen Grenzen so gewählt, daß die Gesamtmenge für das erfindungsgemäße Korrosionsschutzmittel 100% ergibt.These anti-corrosion agents are applied by simply spraying them onto the metal parts to be treated. The respective amounts for components A to E are within the The limits specified are chosen so that the total amount for the anti-corrosion agent according to the invention is 100%.

Das vorteilhafte Korrosionsschutzvermögen der erfindungsgemäßen Korrosionsschutzmittel zeigt sich bei den nachfolgend beschriebenen Testversuchen. Die Versuche bestehen im wesentlichen darin, daß trockene, frisch gebeizte Aluminiumbleche mit den jeweiligen Korrosionsschutzmitteln eingesprüht und unter den Bedingungen des Kesternich-Testes (DIN 50 017) während einer Prüfdauer von bis zu 4 Wochen auf Korrosion beobachtet wurden. Die Korrosionsneigung wurde daneben auch an solchen Aluminiumblechen getestet, die nach dem Einsprühen mit dem Korrosionsschutzmittel noch während 4 Std. einer Anlaß-Glühe von 180° C unterzogen wurden.The advantageous anticorrosive properties of the anticorrosive agents according to the invention can be seen in the test tests described below. The tests essentially consist of spraying dry, freshly pickled aluminum sheets with the respective corrosion protection agents and observing them for corrosion under the conditions of the Kesternich test (DIN 50 017) for up to 4 weeks. The tendency to corrode was also tested on aluminum sheets which, after being sprayed with the anticorrosive agent, were subjected to a tempering anneal of 180 ° C. for 4 hours.

Bei der visuellen Beurteilung der Prüfbleche erfolgt die Benotung mit den Werten 0-4 nach dem folgenden Schema:

Figure imgb0003
In the visual assessment of the test sheets, the scores 0-4 are based on the following scheme:
Figure imgb0003

Die bei den Prüfungen ermittelten Ergebnisse für die Korrosionsschutzmittel 1 bis 5 sind in der nachfolgenden Tabelle zusammengestellt.The results of the tests for corrosion protection agents 1 to 5 are shown in the table below.

Korrosionsschutzmittel:

  • 1. 15% einer Komponente A erhalten durch Umsetzung eines C13/C16-Alkylsulfochlorids mit Ammoniak, anschließende Umsetzung mit Essigsäure und Überführung in das Bariumsalz, 80% eines paraffinischen Kohlenwasserstoffs mit etwa folgender Zusammensetzung:
    Figure imgb0004
    2% Caprylaminoctoat,
    • 2% Nonylphenol mit 2 Mol EO und
    • 1% Isobutanol
  • 2. 15% der Komponente A wie unter 1. beschrieben, jedoch in der Form des Calciumsalzes, 80% des gleichen paraffinischen Kohlenwasserstoffs wie unter 1. beschrieben,
    • 2% Caprylaminoctoat,
    • 2% Nonylphenol mit 2 Mol EO und
    • 1% Isobutanol
  • 3. 4% Fettsäureester aus C16/C18-Fettsäure Jodzahl 27 und Fettalkohol und niederen sowie höheren mehrwertigen Alkoholen
    • 4% Fettsäureglycerid
    • 2% Alkanolaminsalz einer Sulfocarbonsäure
    • 90% Paraffinöl
  • 4. Paraffinischer Kohlenwasserstoff wie in den Korrosionsschutzmitteln 1. und 2. als Komponente B verwendet,
  • 5. Mineralöl
    • Spindelöl 3°E/20°C
Corrosion protection agent:
  • 1. 15% of component A are obtained by reacting a C 13 / C 16 -alkyl sulfochloride with ammonia, then reacting with acetic acid and converting it to the barium salt, 80% of a paraffinic hydrocarbon with the following composition:
    Figure imgb0004
    2% caprylic amino octoate,
    • 2% nonylphenol with 2 mol EO and
    • 1% isobutanol
  • 2. 15% of component A as described under 1., but in the form of the calcium salt, 80% of the same paraffinic hydrocarbon as described under 1.,
    • 2% caprylic amino octoate,
    • 2% nonylphenol with 2 mol EO and
    • 1% isobutanol
  • 3. 4% fatty acid esters from C 16 / C 18 fatty acid iodine number 27 and fatty alcohol and lower and higher polyhydric alcohols
    • 4% fatty acid glyceride
    • 2% alkanolamine salt of a sulfocarboxylic acid
    • 90% paraffin oil
  • 4. Paraffinic hydrocarbon as used in corrosion protection agents 1 and 2 as component B,
  • 5. Mineral oil
    • Spindle oil 3 ° E / 20 ° C

Die Korrosionsschutzmittel 1 und 2 sind erfindungsgemäß und die Mittel 3-5 sind bisher zu diesem Zweck benutzt worden.The anti-corrosion agents 1 and 2 are according to the invention and the agents 3-5 have been used for this purpose.

Korrosionsschutzversuche nach Kesternich (DIN 50 017)

Figure imgb0005
Corrosion protection tests according to Kesternich (DIN 50 017)
Figure imgb0005

Die Untersuchungen wurden auf Aluminiumblechen mit einem Gehalt von 0,5, 1,5 bzw. 3% Magnesium durchgeführt. Bei allen drei Legierungsarten ergaben sich die gleichen Werte mit den jeweils untersuchten Korrosionsschutzmitteln 1-5. Die jeweils unter b) angegebenen Werte beziehen sich auf Proben, die nach dem Einsprühen mit dem Korrosionsschutzmittel 4 Stunden bei 180°C geglüht wurden. Bei den Proben a) fehlt diese Wärmebehandlung.The tests were carried out on aluminum sheets with a content of 0.5, 1.5 or 3% magnesium. The same values were obtained for all three types of alloy with the respective corrosion protection agents 1-5. The values given under b) refer to samples that were annealed for 4 hours at 180 ° C after spraying with the anti-corrosion agent. This heat treatment is absent in samples a).

Claims (2)

1. Anticorrosive agent for aluminium and the alloys thereof consisting of
A) 15 to 50% by weight of a product obtained by reaction of sulfochlorination products of aliphatic, alkylaromatic, or cycloaliphatic hydrocarbons having from 12 to 24 carbon atoms with ammonia or a C1-C3 alkyl or hydroxyalkyl amine with subsequent reaction with a C2-C11 halocarboxylic acid and conversion into an alkaline earth metal or the zinc salt,
B) at least 40% by weight of a paraffinic hydrocarbon containing from 50 to 60% of C13 - C16 paraffins, 50 to 40% of naphthenes and 0 to 1% of aromatics and having a viscosity of from 3 to 5° C/20° C,
C) 1 to 4% by weight of the salt of a C8-C19 alkyl amine and a C8-C10 carboxylic acid,
D) 1 -4% by weight of an oxethylate of 1 mol of a C8-C12 alkylphenol and 2 to 10 mols of ethylene oxide and
E) 1 to 2% by weight of a C4-C8 aliphatic alcohol.
2. Anticorrosive agent as claimed in claim 1, containing up to 50% by weight of component B, 1 to 2% by weight of component C, 1 to 2% by weight of component D and 1 to 2% by weight of component E.
EP80104040A 1979-07-20 1980-07-12 Corrosion inhibiting composition for aluminium and aluminium alloys Expired EP0022999B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19792929413 DE2929413A1 (en) 1979-07-20 1979-07-20 CORROSION PROTECTIVE AGENT FOR ALUMINUM AND ALUMINUM ALLOYS
DE2929413 1979-07-20

Publications (2)

Publication Number Publication Date
EP0022999A1 EP0022999A1 (en) 1981-01-28
EP0022999B1 true EP0022999B1 (en) 1983-03-23

Family

ID=6076282

Family Applications (1)

Application Number Title Priority Date Filing Date
EP80104040A Expired EP0022999B1 (en) 1979-07-20 1980-07-12 Corrosion inhibiting composition for aluminium and aluminium alloys

Country Status (4)

Country Link
US (1) US4323476A (en)
EP (1) EP0022999B1 (en)
JP (1) JPS5616679A (en)
DE (2) DE2929413A1 (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3035327A1 (en) * 1980-09-19 1982-05-06 Hoechst Ag, 6000 Frankfurt COOLING LIQUID WITH CORROSION AND CAVITATION-RESISTANT ADDITIVES
US4452157A (en) * 1982-04-19 1984-06-05 The Singer Company Basting stitch mechanism
US4970026A (en) * 1988-09-21 1990-11-13 Drew Chemical Corporation Corrosion inhibitor

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3632651A (en) * 1967-09-28 1972-01-04 Sumitomo Chemical Co Novel ultraviolet absorbers
FR1592566A (en) * 1967-10-14 1970-05-19
US3692675A (en) * 1970-11-04 1972-09-19 Dow Chemical Co Inhibitor to corrosive attack and method of use
DD117492A1 (en) * 1973-09-19 1976-01-12
DE2614234C2 (en) * 1976-04-02 1982-05-27 Metallgesellschaft Ag, 6000 Frankfurt Treatment liquid for the corrosion protection of metal surfaces and concentrate for their production
CH629540A5 (en) * 1977-09-19 1982-04-30 Hoechst Ag WATER-MIXABLE ANTI-CORROSIVE AGENT.
DD137124A1 (en) * 1978-03-01 1979-08-15 Friedrich Andreas SELF-WAISTING CORROSION PROTECTION
US4192769A (en) * 1978-05-12 1980-03-11 The Lubrizol Corporation Rust inhibitor additive compositions, method of making, and aqueous fluids containing the same

Also Published As

Publication number Publication date
DE3062433D1 (en) 1983-04-28
DE2929413A1 (en) 1981-02-05
US4323476A (en) 1982-04-06
JPS5616679A (en) 1981-02-17
EP0022999A1 (en) 1981-01-28

Similar Documents

Publication Publication Date Title
DE2614234C2 (en) Treatment liquid for the corrosion protection of metal surfaces and concentrate for their production
DE1621430C2 (en) Contact and vapor phase corrosion inhibitor
DE19510825A1 (en) Anticorrosive cleaner for tinned steel
DE2233542C3 (en) Lubricant mixture
DD151185A5 (en) NON-PETROLEUM BASED METAL CORROSION PROTECTION COMPOSITION
DE10011942A1 (en) Decolorization of alkanolamines, useful in cosmetics industry e.g. in soap, washing agent or shampoo, or as dispersant or emulsifier, uses phosphorous or hypophosphorous acid or compound in heat treatment and distillation
DE2461612C3 (en) Rust-dissolving cleaning agents and a process for their production
EP0144663B1 (en) Use of corrosion inhibitors in aqueous systems
WO1982000665A1 (en) Process and product for the passivation of iron and steel surfaces
EP0022999B1 (en) Corrosion inhibiting composition for aluminium and aluminium alloys
CH629540A5 (en) WATER-MIXABLE ANTI-CORROSIVE AGENT.
DE1295962B (en) Process and additives for the production of boehmite on aluminum surfaces
DE907685C (en) Water-repellent mineral oil composition for cold-rolled workpieces made of corrosive metals
DE1769332A1 (en) Lubricating emulsion for metal rolling
EP0231524B1 (en) Application of alkylbenzoylacrylic acids as corrosion inhibitors
AT257795B (en) Emulsifiable lubricating oil composition
DE829037C (en) Process for protecting base metals and their base alloys against salt water corrosion
DE3341013A1 (en) AMBER ACID MONO-DIALKYLAMIDES AS WATER-SOLUBLE CORROSION PROTECTORS
EP0109549B1 (en) Corrosion inhibitors for aqueous solutions for the treatment of metals, and process for their preparation
DE1521710B2 (en) PROCESS FOR MANUFACTURING AN ANTI-CORROSION AGENT
DE2347728A1 (en) COATING DIMENSIONS FOR DELAYING SCALE FORMATION AT TEMPERATURES ABOVE 1177 DEGREES C.
DE60022626T2 (en) MECHANICAL WORK IN THE PRESENCE OF A MULTIFUNCTIONAL REFRIGERANT
DE1645745A1 (en) Corrosion inhibitor for liquid hydrocarbons
EP0192132A2 (en) Aqueous anticorrosive agent containing an ammonium salt of 2-benzothia-zolylthiocarboxylic acid
DE2627030C3 (en) Water-soluble film-forming anti-rust agent

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

Designated state(s): BE DE FR GB IT

17P Request for examination filed

Effective date: 19810327

ITF It: translation for a ep patent filed

Owner name: ING. C. GREGORJ S.P.A.

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Designated state(s): BE DE FR GB IT

REF Corresponds to:

Ref document number: 3062433

Country of ref document: DE

Date of ref document: 19830428

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 19830616

Year of fee payment: 4

ET Fr: translation filed
PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: BE

Payment date: 19830630

Year of fee payment: 4

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: BE

Effective date: 19840731

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 19840810

Year of fee payment: 5

BERE Be: lapsed

Owner name: HOECHST A.G.

Effective date: 19840712

GBPC Gb: european patent ceased through non-payment of renewal fee
PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 19850329

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Effective date: 19860402

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Effective date: 19881118

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