Patent US4260730A successfully refreshed from Google Patents.
US4260730A
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Preparation of bisphenol-formaldehyde ethers using nitric acid
Assignee: DeSoto Inc
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Filing: 1980-01-03
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Granted: 1981-04-07
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Expires: 2000-01-03
Abstract
Abstract A bisphenol is reacted with formaldehyde in solution in alcohol in the presence of an alkali metal hydroxide, preferably at a pH of from 7-10, to provide a polymethylol derivative. Nitric acid is then added to precipitate the hydroxide and an excess is preferably used to provide an acid pH, preferably pH 1-3, and the acidic mixture is heat reacted to remove water of etherification. The nitric acid catalyst is then precipitated with alkali metal hydroxide to enable easy removal of both acid and alkali as an insoluble salt.
Inventors
- 👤 Kazys Sekmakas
- 👤 Thomas H. Plaisance
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 01:41
CPC Classifications
C; C08; C08G; C08G8/00; C08G8/04; C08G8/08
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
74 words
A method for the production of bisphenol-formaldehyde ethers comprising reacting a bisphenol with at least 2 moles of formaldehyde per mol of said bisphenol, the reaction being carried out in solution in alcohol in the presence of an alkali metal hydroxide to provide a polymethylol derivative of said bisphenol, adding nitric acid to precipitate said hydroxide, and then heat reacting said polymethylol derivative alcohol solution at an acid pH while removing water of etherification.
Claim 2
Independent Claim
74 words
A method for the production of bisphenol-formaldehyde ethers comprising reacting a bisphenol with at least 2 moles of formaldehyde per mol of said bisphenol, the reaction being carried out in solution in alcohol in the presence of an alkali metal hydroxide to provide a polymethylol derivative of said bisphenol, adding nitric acid to precipitate said hydroxide, and then heat reacting said polymethylol derivative alcohol solution at an acid pH while removing water of etherification.
Claim 3
Dependent Claim
33 words
A method as recited in claim 1 in which said alcohol is present in stoichiometric excess and said alkali metal hydroxide is used in small amount to provide a pH of from 7-10.
Claim 4
Dependent Claim
32 words
A method as recited in claim 2 in which said excess alcohol is distilled off after water of etherification has been removed to provide a solids content of from 60% to 80%.
Claim 5
Dependent Claim
20 words
A method as recited in claim 1 in which said formaldehyde is used in a 5% to 50% stoichiometric excess.
Claim 6
Dependent Claim
18 words
A method as recited in each of claim 1-4 in which said alkali metal hydroxide is sodium hydroxide.
Claim 7
Dependent Claim
18 words
A method as recited in claim 1 in which said alcohol is a C 1 -C 8 alkanol.
Claim 8
Independent Claim
26 words
A method as recited in each of claims 1-4 in which nitric acid is used to provide a pH of 1-3 for the said etherification reaction.
Claim 9
Dependent Claim
36 words
A method as recited in claim 7 in which said nitric acid catalyst is removed when the etherification reaction has been completed by precipitating the nitric acid with alkali metal hydroxide, and then removing the precipitate.
Claim 10
Dependent Claim
19 words
A method as recited in claim 1 in which said polymethylol derivative contains from 2-4 methylol groups per molecule.
Claim 11
Dependent Claim
24 words
A method as recited in claim 9 in which said etherification reaction is carried out to provide from 2-4 etherified methylol groups per molecule.
Claim 12
Independent Claim
16 words
A method as recited in each of claims 1-4 in which said alcohol is a butanol.
Claim 13
Independent Claim
92 words
A method for the production of bisphenol-formaldehyde ethers comprising reacting bisphenol A with a 5% to 50% stoichiometric excess of formaldehyde in solution in excess C 4 -C 8 alkanol in the presence of an alkali metal hydroxide at a pH of from 7-10 to provide a polymethylol derivative of said bisphenol A, adding nitric acid to provide a pH of 1-3, heat reacting the acidic mixture while removing water of etherification, precipitating the nitric acid with alkali metal hydroxide when the etherification reaction has been completed, and then removing the precipitate.
Claim 14
Independent Claim
92 words
A method for the production of bisphenol-formaldehyde ethers comprising reacting bisphenol A with a 5% to 50% stoichiometric excess of formaldehyde in solution in excess C 4 -C 8 alkanol in the presence of an alkali metal hydroxide at a pH of from 7-10 to provide a polymethylol derivative of said bisphenol A, adding nitric acid to provide a pH of 1-3, heat reacting the acidic mixture while removing water of etherification, precipitating the nitric acid with alkali metal hydroxide when the etherification reaction has been completed, and then removing the precipitate.
Claim 15
Dependent Claim
47 words
A method as recited in claim 8 in which the precipitate-free product is tested for residual unneutralized alkali metal hydroxide or nitric acid, and the trace of either which remains is removed by precipitation with alkali metal hydroxide or nitric acid followed by removal of the precipitate.
Claim 16
Dependent Claim
14 words
A method as recited is claim 12 in which the alkanol is a butanol.
References Cited (Backward Citations)
US3220964A
Cited
US4182732A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-04-06 | 1984-10-06 | 1985-04-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-04-06 | 1988-10-06 | 1989-04-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-04-06 | 1992-10-06 | 1993-04-07 | $7700.00 | Window Closed / Lapsed |