US4982014A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dihydroxydiphenyl cycloalkanes, their production and their use for the production of high molecular weight polycarbonates
Assignee: Bayer AG
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Filing: 1989-08-04
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Granted: 1991-01-01
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Expires: 2009-08-04
Abstract
Abstract Dihydroxydiphenyl cycloalkanes corresponding to the formula <IMAGE> (I) in which R1 and R2 independently of one another represent hydrogen, halogen, C1-C8 alkyl, C5-C6 cycloalkyl, C6-C10 aryl and C7-C12 aralkyl, m is an integer of from 4 to 7, R3 and R4, individually selectable for each X, independently of one another represent hydrogen or C1-C6 alkyl and X represents carbon with the proviso that, at at least one atom X, both R3 and R4 are alkyl, a process for their production, their use for the production of high molecular weight polycarbonates, the polycarbonates made from dihydroxydiphenyl cycloalkane of formula (I) and films made from these polycarbonates.
Inventors
- 👤 Dieter Freitag
- 👤 Uwe Westeppe
- 👤 Claus H. Wulff
- 👤 Karl-Herbert Fritsch
- 👤 Carl Casser
- 👤 Gunther Weymans
- 👤 Lutz Schrader
- 👤 Werner Waldenrath
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 21:32
CPC Classifications
B; B01; B01D; B01D71/00; B01D71/06; B01D71/50; C; C07; C07C; C07C39/00; C07C39/12; C07C39/17; C08; C08G; C08G64/00; C08G64/04; C08G64/06; C07C2601/00; C07C2601/12; C07C2601/14
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
99 words
Dihydroxydiphenyl cycloalkanes corresponding to the formula ##STR16## in which R 1 and R 2 independently of one another represent hydrogen, halogen, C 1 -C 8 -alkyl, C 5 -C 6 cycloalkyl, C 5 -C 10 -aryl and C 7 -C 12 aralkyl, m is an integer of from 4 to 7, R 3 and R 4 , individually selectable for each X, independently of one another represent hydrogen of C 1 -C 6 -alkyl and R 5 represents carbon, with the proviso that, at at least one atom R 5 , both R 3 and R 4 are alkyl.
Claim 2
Dependent Claim
99 words
Dihydroxydiphenyl cycloalkanes corresponding to the formula ##STR16## in which R 1 and R 2 independently of one another represent hydrogen, halogen, C 1 -C 8 -alkyl, C 5 -C 6 cycloalkyl, C 5 -C 10 -aryl and C 7 -C 12 aralkyl, m is an integer of from 4 to 7, R 3 and R 4 , individually selectable for each X, independently of one another represent hydrogen of C 1 -C 6 -alkyl and R 5 represents carbon, with the proviso that, at at least one atom R 5 , both R 3 and R 4 are alkyl.
Claim 3
Dependent Claim
26 words
Dihydroxydiphenyl cycloalkanes corresponding to formula (I) as claimed in claim 1, wherein neither of the two R 5 atoms in the α-position to C-1 is dialkyl-substituted.
Claim 4
Dependent Claim
23 words
Dihydroxydiphenyl cycloalkanes corresponding to formula (I) as claimed in claim 1, wherein a dialkyl-substituted R 5 -atom is in the β-position to C-1.
Claim 5
Dependent Claim
17 words
Dihydroxydiphenyl cycloalkanes corresponding to formula (I) as claimed in claim 1, wherein m is 4 or 5.
Claim 6
Dependent Claim
2 words
1,1-Bis-(4-hydroxyphenyl)-3,3,5-trimethyl cyclohexane.
Claim 7
Dependent Claim
2 words
1,1-Bis-(4-hydroxyphenyl)-3,3,5-trimethyl cyclohexane.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1993-12-31 | 1994-07-02 | 1995-01-01 | $2000.00 | Window Closed / Lapsed |
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