Patent US1826647A successfully refreshed from Google Patents.
Patent US4320023A successfully refreshed from Google Patents.
US4320023A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Antifreeze formulation useful for retarding precipitation of aluminum corrosion products in the cooling systems of internal combustion engines
Assignee: Ashland LLC
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Filing: 1980-12-05
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Granted: 1982-03-16
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Expires: 2000-12-05
Abstract
Abstract Precipitation of aluminum corrosion products from phosphate-borate ethylene glycol based antifreeze formulations is retarded by incorporating in the antifreeze a precipitation retarding amount of alkylene diphosphonic acid, e.g., 1-hydroxyethylidene-1,1-diphosphonic acid.
Inventors
- 👤 Preston S. White
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 11:45
CPC Classifications
C; C09; C09K; C09K5/00; C09K5/20
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
79 words
A phosphate-borate ethylene glycol based antifreeze formulation especially useful for retarding precipitation of aluminum corrosion products in the cooling system of an internal combustion engine said antifreeze formulation containing from about 50 to about 500 parts by weight per million parts by weight of antifreeze of alkylene diphosphonic acid represented by the formula: ##STR2## wherein R is hydrogen or C 1 to C 4 is alkyl; and R' is hydrogen, hydroxyl, amino or C 1 to C 4 alkyl.
Claim 2
Dependent Claim
79 words
A phosphate-borate ethylene glycol based antifreeze formulation especially useful for retarding precipitation of aluminum corrosion products in the cooling system of an internal combustion engine said antifreeze formulation containing from about 50 to about 500 parts by weight per million parts by weight of antifreeze of alkylene diphosphonic acid represented by the formula: ##STR2## wherein R is hydrogen or C 1 to C 4 is alkyl; and R' is hydrogen, hydroxyl, amino or C 1 to C 4 alkyl.
Claim 3
Dependent Claim
27 words
The antifreeze formulation of claim 1 containing from about 250 to about 500 parts by weight per million parts by weight of antifreeze of alkylene diphosphonic acid.
Claim 4
Dependent Claim
14 words
The antifreeze formulation of claim 1 wherein the alkylene diphosphonic acid is 1-hydroxyethylidene-1,1-diphosphonic acid.
Claim 5
Independent Claim
80 words
A method of retarding precipitation of aluminum corrosion products in cooling systems associated with internal combustion engines having aluminum components in contact with phosphate-borate based antifreeze by incorporating in the antifreeze from about 50 to about 500 parts by weight per million parts by weight of antifreeze of alkylene diphosphonic acid represented by the formula: ##STR3## wherein R is hydrogen or C 1 to C 4 alkyl; and R' is hydrogen, hydroxyl, amino or C 1 to C 4 alkyl.
Claim 6
Independent Claim
80 words
A method of retarding precipitation of aluminum corrosion products in cooling systems associated with internal combustion engines having aluminum components in contact with phosphate-borate based antifreeze by incorporating in the antifreeze from about 50 to about 500 parts by weight per million parts by weight of antifreeze of alkylene diphosphonic acid represented by the formula: ##STR3## wherein R is hydrogen or C 1 to C 4 alkyl; and R' is hydrogen, hydroxyl, amino or C 1 to C 4 alkyl.
Claim 7
Dependent Claim
27 words
The method of claim 4 wherein the antifreeze contains from about 250 to about 500 parts by weight per million parts of antifreeze of alkylene diphosphonic acid.
Claim 8
Dependent Claim
13 words
The method of claim 4 wherein the alkylene diphosphonic acid is 1-hydroxyethylidene-1,1-diphosphonic acid.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-03-15 | 1985-09-14 | 1986-03-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-03-15 | 1989-09-14 | 1990-03-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-03-15 | 1993-09-14 | 1994-03-16 | $7700.00 | Window Closed / Lapsed |