US4810404A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Nitrite- and phosphate-free glycol-based coolant mixtures
Assignee: BASF SE
•
Filing: 1988-02-26
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Granted: 1989-03-07
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Expires: 2008-02-26
Abstract
Abstract Glycol-based coolant mixtures which are free of nitrites and phosphates contain alkali metal salts of bis(carboxyalkyloxyphenyl)-2,2-propane and stabilized silicate and also further corrosion-inhibiting additives.
Inventors
- 👤 Charalampos Gousetis
- 👤 Knut Oppenlaender
- 👤 Gert Liebold
- 👤 Guenter Frey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 12:21
CPC Classifications
C; C09; C09K; C09K5/00; C09K5/20
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
122 words
A glycol-based coolant mixture which is free of nitrites and phosphates, containing (a) 1-5% by weight of an alkali metal salt of acid II ##STR7## where R is a --CH 2 --, --CH--, --CH-- or CH 2 CH 2 CH 2 group, (b) 0.1-1% by weight of a silicate of the general formula III (MO).sub.q SiO.sub.4-q/2 (III) where M is an alkali metal and q is from 0.4 to 4, (c) 0.01-0.2% by weight of a silicate stabilizer, (d) 0-0.5% by weight of an alkali nitrate, (e) 0.05-0.2% by weight of benzotriazole or tolyltriazole, (f) 0.5-2 % by weight of borax, and (g) 0.05-1 % by weight of NaOH, all the percentages being based on the glycol present in the coolant mixture.
Claim 2
Dependent Claim
122 words
A glycol-based coolant mixture which is free of nitrites and phosphates, containing (a) 1-5% by weight of an alkali metal salt of acid II ##STR7## where R is a --CH 2 --, --CH--, --CH-- or CH 2 CH 2 CH 2 group, (b) 0.1-1% by weight of a silicate of the general formula III (MO).sub.q SiO.sub.4-q/2 (III) where M is an alkali metal and q is from 0.4 to 4, (c) 0.01-0.2% by weight of a silicate stabilizer, (d) 0-0.5% by weight of an alkali nitrate, (e) 0.05-0.2% by weight of benzotriazole or tolyltriazole, (f) 0.5-2 % by weight of borax, and (g) 0.05-1 % by weight of NaOH, all the percentages being based on the glycol present in the coolant mixture.
Claim 3
Dependent Claim
19 words
A coolant mixture as defined in claim 1, which contains as component (a) the sodium salt of isopropylidenbis(p-phenoxyacetic acid).
Claim 4
Dependent Claim
150 words
A coolant mixture as defined in claim 1, which contains as component (c) a silicate stabilizer of the formula ##STR8## where Y is a divalent aliphatic or cycloaliphatic radical of 1 to 10 carbon atoms or phenylenealkylene of 7 to 10 carbon atoms, n can be 1 or 2, in the case of n=1 X being OR 3 where R 3 is straight-chain, branched or cyclic alkyl of 1 to 13 carbon atoms, which may be interrupted by oxygen, or acyl of up to 9 carbon atoms, and R 1 and R 2 being identical or different and each being a straight-chain, branched or cyclic alkyl of 1 to 13 carbon atoms, which may be interrupted by oxygen, or aryl or aralkyl of up to 20 carbon atoms, and in the case of n=2 X being oxygen, R 1 being an alkali metal and R 2 having the abovementioned meanings.
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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) | 1992-03-06 | 1992-09-05 | 1993-03-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-03-06 | 1996-09-05 | 1997-03-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-03-06 | 2000-09-05 | 2001-03-07 | $7700.00 | Window Closed / Lapsed |