US4689201A
Expired / Lapsed
US
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Prevention of corrosion
Assignee: Grace Dearborn Ltd
•
Filing: 1985-03-05
•
Granted: 1987-08-25
•
Expires: 2005-03-05
Abstract
Abstract Corrosion in liquid, especially aqueous systems such as cooling systems, is controlled by the addition of a vegetable tannin or a derivative thereof, a triazole, a hydroxylamine, a neutralizing amine, and a water soluble salt of a Group II metal, in particular zinc, magnesium or calcium.
Inventors
- 👤 Stuart W. Longworth
- 👤 John G. Baker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 22:49
CPC Classifications
C; C09; C09K; C09K5/00; C09K5/20; C23; C23F; C23F11/00; C23F11/08
Claims Analysis
Total Claims: 72
Claim 1
Independent Claim
158 words
A method of inhibiting corrosion in a liquid system which comprises adding to the system at least one vegetable tannin or a derivative thereof, a water soluble salt of a metal of Group II in the Periodic Table, a triazole, a hydroxylamine and a neutralizing amine, together in an amount effective to substantially reduce corrosion of system components; wherein said tannin is added in an amount of from about 10 ppm to about 5000 ppm; wherein said hydroxylamine is added in an amount of from about 10 ppm to about 5000 ppm; wherein said neutralizing amine is added in an amount of from about 10 ppm to about 5000 ppm; and wherein said salt is added in an amount of from about 5 ppm to about 500 ppm such that the corrosion rate of any aluminum components incorporated in the system and contacted with the system liquid is substantially less than their corrosion rate without said salt addition.
Claim 2
Independent Claim
158 words
A method of inhibiting corrosion in a liquid system which comprises adding to the system at least one vegetable tannin or a derivative thereof, a water soluble salt of a metal of Group II in the Periodic Table, a triazole, a hydroxylamine and a neutralizing amine, together in an amount effective to substantially reduce corrosion of system components; wherein said tannin is added in an amount of from about 10 ppm to about 5000 ppm; wherein said hydroxylamine is added in an amount of from about 10 ppm to about 5000 ppm; wherein said neutralizing amine is added in an amount of from about 10 ppm to about 5000 ppm; and wherein said salt is added in an amount of from about 5 ppm to about 500 ppm such that the corrosion rate of any aluminum components incorporated in the system and contacted with the system liquid is substantially less than their corrosion rate without said salt addition.
Claim 3
Dependent Claim
18 words
A method according to claim 1 in which the salt is a salt of zinc, magnesium or calcium.
Claim 4
Dependent Claim
13 words
A method according to claim 2 in which the salt is calcium acetate.
Claim 5
Independent Claim
112 words
A method of inhibiting corrosion in a liquid system wherein the liquid contacts system components made of aluminum which comprises adding to the system at least one vegetable tannin or a derivative thereof, a water soluble magnesium salt, a hydroxylamine, a neutralizing amine and a triazole, together in an amount effective to substantially reduce corrosion of system components; wherein said tannin is added in an amount of from about 10 ppm to about 5000 ppm and said salt is added in an amount of from about 5 ppm to about 500 ppm such that the corrosion rate of aluminum system components is substantially less than their corrosion rate without said salt addition.
Claim 6
Independent Claim
112 words
A method of inhibiting corrosion in a liquid system wherein the liquid contacts system components made of aluminum which comprises adding to the system at least one vegetable tannin or a derivative thereof, a water soluble magnesium salt, a hydroxylamine, a neutralizing amine and a triazole, together in an amount effective to substantially reduce corrosion of system components; wherein said tannin is added in an amount of from about 10 ppm to about 5000 ppm and said salt is added in an amount of from about 5 ppm to about 500 ppm such that the corrosion rate of aluminum system components is substantially less than their corrosion rate without said salt addition.
Claim 7
Dependent Claim
12 words
A method according to claim 4 in which the triazole is benzotriazole.
Claim 8
Dependent Claim
20 words
A method according to claim 4 in which the triazole is incorporated in an amount from 5 to 100 ppm.
Claim 9
Dependent Claim
44 words
A method according to claim 1 in which the hydroxylamine has the formula: ##STR2## wherein R 1 , R 2 and R 3 independently represent hydrogen, alkyl of 1 to 8 carbon atoms, aryl or aryl (lower alkylene), or a water soluble salt thereof.
Claim 10
Dependent Claim
12 words
A method according to claim 7 in which the hydroxylamine is N,N-diethyl-hydroxylamine.
Claim 11
Dependent Claim
44 words
A method according to claim 4 in which the hydroxylamine has the formula: ##STR3## wherein R 1 , R 2 and R 3 independently represent hydrogen, alkyl of 1 to 8 carbon atoms, aryl or aryl (lower alkylene), or a water soluble salt thereof.
Claim 12
Dependent Claim
12 words
A method according to claim 9 in which the hydroxylamine is N,N-diethyl-hydroxylamine.
Claim 13
Dependent Claim
13 words
A method according to claim 1 in which the neutralising amine is 2-amino-2-methylpropanol.
Claim 14
Dependent Claim
13 words
A method according to claim 4 in which the neutralising amine is 2-amino-2-methylpropanol.
Claim 15
Dependent Claim
34 words
A method according to claim 1 in which the amount of the hydroxylamine and neutralising amine added is from 500 to 3,000 ppm, the weight ratio of hydroxylamine:neutralising amine being from 0.001 to 10:1.
Claim 16
Dependent Claim
34 words
A method according to claim 4 in which the amount of the hydroxylamine and neutralising amine added is from 500 to 3,000 ppm, the weight ratio of hydroxylamine:neutralising amine being from 0.001 to 10:1.
Claim 17
Independent Claim
108 words
A method of inhibiting corrosion in a liquid system wherein the liquid contacts system components made of aluminum which comprises adding to the system at least one vegetable tannin or a derivative thereof, a triazole, and a water soluble salt of calcium, together in an amount effective to substantially reduce corrosion of system components; wherein said tannin is added in an amount of from about 10 ppm to about 5000 ppm and said salt is added in an amount of from about 5 ppm to about 500 ppm such that the corrosion rate of aluminum system components is substantially less than their corrosion rate without said salt addition.
Claim 18
Independent Claim
108 words
A method of inhibiting corrosion in a liquid system wherein the liquid contacts system components made of aluminum which comprises adding to the system at least one vegetable tannin or a derivative thereof, a triazole, and a water soluble salt of calcium, together in an amount effective to substantially reduce corrosion of system components; wherein said tannin is added in an amount of from about 10 ppm to about 5000 ppm and said salt is added in an amount of from about 5 ppm to about 500 ppm such that the corrosion rate of aluminum system components is substantially less than their corrosion rate without said salt addition.
Claim 19
Dependent Claim
23 words
The method according to claim 1 in which the tannin is a sulphited extract of one or more naturally occurring catechol-based vegetable tannins.
Claim 20
Dependent Claim
23 words
A method according to claim 4 in which the tannin is a sulphited extract of one or more naturally occurring catechol-based vegetable tannins.
Claim 21
Dependent Claim
23 words
A method according to claim 15 in which the tannin is a sulphited extract of one or more naturally occurring catechol-based vegetable tannins.
Claim 22
Dependent Claim
14 words
A method according to claim 15 in which the system is an aqueous system.
Claim 23
Dependent Claim
15 words
A method according to claim 19 in which the aqueous system is a closed system.
Claim 24
Dependent Claim
16 words
A method according to claim 1 in which the salt is a chloride, nitrate or acetate.
Claim 25
Dependent Claim
16 words
A method according to claim 4 in which the salt is a chloride, nitrate or acetate.
Claim 26
Dependent Claim
16 words
A method according to claim 15 in which the salt is a chloride, nitrate or acetate.
Claim 27
Dependent Claim
14 words
A method according to claim 15 which further comprises adding an additional corrosion inhibitor.
Claim 28
Dependent Claim
20 words
A method according to claim 1 in which the tannin is incorporated in an amount from 500 to 3,000 ppm.
Claim 29
Dependent Claim
20 words
A method according to claim 4 in which the tannin is incorporated in an amount from 500 to 3,000 ppm.
Claim 30
Dependent Claim
20 words
A method according to claim 15 in which the tannin is incorporated in an amount from 500 to 3,000 ppm.
Claim 31
Dependent Claim
20 words
A method according to claim 1 in which the salt is incorporated in an amount from 10 to 100 ppm.
Claim 32
Dependent Claim
20 words
A method according to claim 4 in which the salt is incorporated in an amount from 10 to 100 ppm.
Claim 33
Dependent Claim
20 words
A method according to claim 15 in which the salt is incorporated in an amount from 10 to 100 ppm.
Claim 34
Dependent Claim
19 words
A method according to claim 30 in which the salt is incorporated in amount from 20 to 30 ppm.
Claim 35
Dependent Claim
14 words
A method according to claim 15 in which the system is an alcoholic system.
Claim 36
Dependent Claim
26 words
A method according to claim 32 in which the alcohol is methyl, ethyl or propyl alcohol, ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol or glycerol.
Claim 37
Dependent Claim
25 words
A method according to claim 33 in which the system comprises 10 to 50% by weight alcohol and 90 to 40% by weight of water.
Claim 38
Dependent Claim
50 words
An anti-corrosive composition which comprises a tannin and a water soluble salt of a metal of Group II of the Periodic Table, a triazole, a hydroxylamine and a neutralizing amine; wherein the weight ratio of the salt, expressed as the metal, to tannin is from about 0.0025:1 to about 0.1:1.
Claim 39
Dependent Claim
50 words
An anti-corrosive composition which comprises a tannin and a water soluble salt of a metal of Group II of the Periodic Table, a triazole, a hydroxylamine and a neutralizing amine; wherein the weight ratio of the salt, expressed as the metal, to tannin is from about 0.0025:1 to about 0.1:1.
Claim 40
Dependent Claim
17 words
A composition according to claim 35 in which the salt is a zinc, magnesium or calcium salt.
Claim 41
Dependent Claim
13 words
A composition according to claim 36 in which the salt is calcium acetate.
Claim 42
Dependent Claim
41 words
An anti-corrosive composition which comprises a tannin and a water soluble magnesium salt, a hydroxylamine, a neutralizing amine and a triazole; wherein the weight ratio of the salt, expressed as the magnesium, to tannin is from about 0.0025:1 to about 0.1:1.
Claim 43
Dependent Claim
41 words
An anti-corrosive composition which comprises a tannin and a water soluble magnesium salt, a hydroxylamine, a neutralizing amine and a triazole; wherein the weight ratio of the salt, expressed as the magnesium, to tannin is from about 0.0025:1 to about 0.1:1.
Claim 44
Dependent Claim
13 words
A composition according to claim 38 in which the the triazole is benzotriazole.
Claim 45
Dependent Claim
45 words
A composition according to claim 35 in which the hydroxylamine has the formula: ##STR4## wherein R 1 , R 2 , and R 3 independently represent hydrogen, alkyl of 1 to 8 carbon atoms, aryl or aryl (lower alkylene), or a water soluble salt thereof.
Claim 46
Dependent Claim
12 words
A composition according to claimm 40 in which the hydroxylamine is N,N-diethyl-hydroxylamine.
Claim 47
Dependent Claim
45 words
A composition according to claim 38 in which the hydroxylamine has the formula: ##STR5## wherein R 1 , R 2 , and R 3 independently represent hydrogen, alkyl of 1 to 8 carbon atoms, aryl or aryl (lower alkylene), or a water soluble salt thereof.
Claim 48
Dependent Claim
12 words
A composition according to claim 42 in which the hydroxylamine is N,N-diethyl-hydroxylamine.
Claim 49
Dependent Claim
13 words
A composition according to claim 35 in which the neutralising amine is 2-amino-2-methylpropanol.
Claim 50
Dependent Claim
13 words
A composition according to claim 38 in which the neutralising amine is 2-amino-2-methylpropanol.
Claim 51
Dependent Claim
13 words
A composition according to claim 35 which further comprises another corrosion inhibiting material.
Claim 52
Dependent Claim
13 words
A composition according to claim 38 which further comprises another corrosion inhibiting material.
Claim 53
Dependent Claim
37 words
An anti-corrosive composition which consists essentially of a tannin, a triazole, and a water soluble salt of calcium; wherein the weight ratio of the salt, expressed as calcium, to tannin is from about 0.0025:1 to about 0.1:1.
Claim 54
Dependent Claim
37 words
An anti-corrosive composition which consists essentially of a tannin, a triazole, and a water soluble salt of calcium; wherein the weight ratio of the salt, expressed as calcium, to tannin is from about 0.0025:1 to about 0.1:1.
Claim 55
Dependent Claim
55 words
A composition according to claim 35 which comprises about 0.05 to about 25% by weight of tannin, hydroxylamine and neutralising amine, about 0.015 to about 1.5% by weight of triazole and about 0.05 to about 5% by weight (as metal) of the salt, the weight ratio of tannin-triazole being from about 0.1:3 to about 5000:3.
Claim 56
Dependent Claim
55 words
A composition according to claim 49 which comprises about 2.5 to about 15% by weight of tannin, hydroxylamine and neutralising amine, about 0.025 to about 0.5% by weight of triazole and about 0.1 to about 1% by weight (as metal) of metal salt, the weight ratio of tannin:triazole being from about 5:1 to about 600:1.
Claim 57
Dependent Claim
38 words
A composition according to claim 50 which comprises about 10% by weight of tannin, N,N-diethylhydroxylamine and 2-amino-methylpropanol, about 0.2% by weight of benzotriazole, about 0.3% by weight of calcium acetate and about 0.5% by weight of acetic acid.
Claim 58
Dependent Claim
23 words
A composition according to claim 35 in which the tannin is a sulphited extract of one or more naturally occurring catechol-based vegetable tannins.
Claim 59
Dependent Claim
23 words
A composition according to claim 38 in which the tannin is a sulphited extract of one or more naturally occurring catechol-based vegetable tannins.
Claim 60
Dependent Claim
23 words
A composition according to claim 48 in which the tannin is a sulphited extract of one or more naturally occurring catechol-based vegetable tannins.
Claim 61
Dependent Claim
16 words
A composition according to claim 35 in which the salt is a chloride, nitrate or acetate.
Claim 62
Dependent Claim
16 words
A composition according to claim 38 in which the salt is a chloride, nitrate or acetate.
Claim 63
Dependent Claim
16 words
A composition according to claim 48 in which the salt is a chloride, nitrate or acetate.
Claim 64
Dependent Claim
22 words
A composition according to claim 35 in which the weight ratio of the salt, expressed as metal:tannin is from 0.005:1 to 0.05:1.
Claim 65
Dependent Claim
22 words
A composition according to claim 38 in which the weight ratio of the salt, expressed as metal:tannin is from 0.005:1 to 0.05:1.
Claim 66
Dependent Claim
22 words
A composition according to claim 48 in which the weight ratio of the salt, expressed as metal:tannin is from 0.005:1 to 0.05:1.
Claim 67
Dependent Claim
11 words
A composition according to claim 48 which further comprises an alcohol.
Claim 68
Dependent Claim
21 words
A composition according to claim 61 in which the alcohol is ethyl, methyl or propyl alcohol, ethylene glycol or propylene glycol.
Claim 69
Dependent Claim
36 words
A composition according to claim 62 which is in the form of a functional fluid for use in an internal combustion engine, a brake or other hydraulic system, a heating system or an air conditioning system.
Claim 70
Dependent Claim
39 words
A method according to claim 1 wherein the liquid system is an aqueous system in which the water used is deionized or base exchanged such that it is substantially free of hardness before addition of the corrosion inhibiting ingredients.
Claim 71
Dependent Claim
39 words
A method according to claim 4 wherein the liquid system is an aqueous system in which the water used is deionized or base exchanged such that it is substantially free of hardness before addition of the corrosion inhibiting ingredients.
Claim 72
Dependent Claim
39 words
A method according to claim 15 wherein the liquid system is an aqueous system in which the water used is deionized or base exchanged such that it is substantially free of hardness before addition of the corrosion inhibiting ingredients.
References Cited (Backward Citations)
GB802875A
Cited
US3256203A
Cited
GB1174829A
Cited
GB1244123A
Cited
US3837803A
Cited
GB1423920A
Cited
US3989637A
Cited
US4209487A
Cited
GB1559725A
Cited
US4389371A
Cited
US4350606A
Cited
US4501667A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-08-24 | 1991-02-23 | 1991-08-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-08-24 | 1995-02-23 | 1995-08-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-08-24 | 1999-02-23 | 1999-08-25 | $7700.00 | Window Closed / Lapsed |