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US5064552A Expired / Lapsed US ⏱️ 0.0 years remaining

Nitrite- and phosphate-free antifreeze based on glycol

Assignee: BASF SE
•
Filing: 1991-02-26
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Granted: 1991-11-12
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Expires: 2011-02-26
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Abstract

Abstract A glycol-based antifreeze mixture which is free of nitrites and phosphates contains an alkali metal salt of a C4-C16-alkenylsuccinic acid, stabilized silicate and further corrosion-inhibiting additives.

Inventors

  • 👤 Knut Oppenlaender
  • 👤 Juergen Mohr
  • 👤 Gert Liebold
  • 👤 Guenter Frey

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 03:43
CPC Classifications
C; C09; C09K; C09K5/00; C09K5/20; C23; C23F; C23F11/00; C23F11/08

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 148 words
An antifreeze mixture for internal combustion engines based on ethylene glycol and/or propylene glycol which is free of nitrite and phosphate, consisting essentially of a) 1-5% by weight of an alkali metal salt of a C 4 -C 16 -alkenylsuccinic acid, b) 0.1-1% by weight of silicate of the formula II (MO).sub.q SiO.sub.4-q/2 (II) 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 metal nitrate, e) 0.05-2.0% by weight of benzotriazole or tolutriazole, f) 0.5-2% by weight of borax, g) 0.05-1% by weight of NaOH, h) 0.01-0.15% by weight of an oligo- or polycarboxylic acid having a molecular weight of 1000 to 100,000, and i) ethylene glycol and/or propylene glycol. all the percentages being based on the amount of ethylene glycol and/or propylene glycol present in the antifreeze mixture.
Claim 2
Dependent Claim 148 words
An antifreeze mixture for internal combustion engines based on ethylene glycol and/or propylene glycol which is free of nitrite and phosphate, consisting essentially of a) 1-5% by weight of an alkali metal salt of a C 4 -C 16 -alkenylsuccinic acid, b) 0.1-1% by weight of silicate of the formula II (MO).sub.q SiO.sub.4-q/2 (II) 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 metal nitrate, e) 0.05-2.0% by weight of benzotriazole or tolutriazole, f) 0.5-2% by weight of borax, g) 0.05-1% by weight of NaOH, h) 0.01-0.15% by weight of an oligo- or polycarboxylic acid having a molecular weight of 1000 to 100,000, and i) ethylene glycol and/or propylene glycol. all the percentages being based on the amount of ethylene glycol and/or propylene glycol present in the antifreeze mixture.
Claim 3
Dependent Claim 30 words
The antifreeze mixture of claim 1, wherein component (a) is the sodium salt of a C 8 -, C 9 - or C 12 -alkenylsuccinic acid or a mixture thereof.
Claim 4
Dependent Claim 153 words
The antifreeze mixture of claim 1, wherein component (c) is a silicate stabilizer of the formula ##STR4## where Y is a divalent aliphatic or cycloaliphatic radical of from 1 to 10 carbon atoms or a phenylenealkylene group of from 7 to 10 carbon atoms and n is 1 or 2, wherein, when n=1, X is an OR 3 group where R 3 is straight-chain, branched or cyclic alkyl of from 1 to 13 carbon atoms which may be interrupted by oxygen atoms or acyl of up to 9 carbon atoms, and R 1 and R 2 , which are identical or different, are each a straight-chain or branched or cyclic alkyl of from 1 to 13 carbon atoms which may be interrupted by oxygen, or aryl or aralkyl of up to 20 carbon atoms, and when n=2, X is oxygen, R 1 is an alkali metal and R 2 is as defined above.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-11-11 1995-05-13 1995-11-12 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-11-11 1999-05-13 1999-11-12 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-11-11 2003-05-13 2003-11-12 $7700.00 Window Closed / Lapsed

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