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US4503266A Expired / Lapsed US ⏱️ 0.0 years remaining

Condensation process

Assignee: Isovolta AG
•
Filing: 1984-06-07
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Granted: 1985-03-05
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Expires: 2004-06-07
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Abstract

Abstract In a process for the preparation of phenol-aromatic ketone condensation products by reaction of phenols and ketones in the presence of a gaseous hydrogen halide, the improvement comprising adding in catalytic amounts up to less than molar amounts based on the ketone as an additional condensation agent at least one bivalent, trivalent or tetravalent metal halide, introducing the gaseous hydrogen halide and after termination of the condensation reaction, adding water to the reaction mixture and recovering the purified condensation product and to the novel monomers of 9,9-bis-(4-hydroxyphenyl)-fluorene with a melting point of at least 226° C. and 1,1-bis-(4-hydroxyphenyl)-1-phenylethene with a melting point of at least 189° C. which are useful for the preparation of improved polyester resins.

Inventors

  • 👤 Otto Szabolcs

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 21:08
CPC Classifications
C; C07; C07C; C07C39/00; C07C39/12; C07C39/15; C07C39/16; C07C39/17; C07C2603/00; C07C2603/02; C07C2603/04; C07C2603/06; C07C2603/10; C07C2603/12; C07C2603/18

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 10 words
9,9-bis-(4-hydrophenyl)-fluorene with a melting point of at least 228° C.
Claim 2
Dependent Claim 10 words
9,9-bis-(4-hydrophenyl)-fluorene with a melting point of at least 228° C.
Claim 3
Dependent Claim 10 words
1,1-bis-(4-hydroxyphenyl)-1-phenylethane with a melting point of at least 189° C.
Claim 4
Dependent Claim 10 words
1,1-bis-(4-hydroxyphenyl)-1-phenylethane with a melting point of at least 189° C.

References Cited (Backward Citations)

US2429556A Cited
US3350352A Cited
US3457316A Cited
US3485795A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1988-03-04 1988-09-03 1989-03-05 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1992-03-04 1992-09-03 1993-03-05 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1996-03-04 1996-09-03 1997-03-05 $7700.00 Window Closed / Lapsed

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