US4325890A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Phenol-formaldehyde condensates, their preparation and their use as dispersing agents, liquefaction agents and tanning agents
Assignee: Bayer AG
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Filing: 1980-08-08
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Granted: 1982-04-20
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Expires: 2000-08-08
Abstract
Abstract Polycondensates of phenols and formaldehyde which contain sulphonic acid groups and salts thereof bonded to the phenol either directly or via a methylene bridge are prepared by reacting a neutralized reaction product of phenols and sulphonating agents, which contains a mixture of the starting phenol, phenolsulphonic acid and bis-(hydroxyphenyl) sulphones, with formaldehyde and a bisulphite at a pH value of 4-8.
Inventors
- 👤 Gunther Reitz
- 👤 Vaclav Kaspar
- 👤 Karlhans Jakobs
- 👤 Kurt Schaupp
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 16:39
CPC Classifications
C; C08; C08G; C08G8/00; C08G8/04; C08G8/08; C08G8/18; C08G8/24; C08G8/28; C09; C09B; C09B67/00; C09B67/0071; C09B67/0072; C09B67/0084; C09B67/0085; C09B67/0086; C09K; C09K23/00; C09K23/12; C14; C14C; C14C3/00; C14C3/02; C14C3/08; C14C3/18; C14C3/20; D; D06; D06P; D06P1/00; D06P1/44; D06P1/52; D06P1/56
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
89 words
Polycondensates of phenols and formaldehyde which contain sulphonic acid groups and salts thereof bonded to the phenol either directly or via a methylene bridge, characterized in that they are prepared in a one-kettle reaction, by reaction of 1 mol of the phenol with 0.3-0.9 mol of sulphonating agent in a strongly acid medium, neutralization of the product to a pH value of 7-8, further reaction with 0.6-2 mols of formaldehyde, reaction with 0.3-0.9 mol of bisulphite and then with 0.8-1.5 mols of formaldehyde at a pH value of 4-8.
Claim 2
Dependent Claim
89 words
Polycondensates of phenols and formaldehyde which contain sulphonic acid groups and salts thereof bonded to the phenol either directly or via a methylene bridge, characterized in that they are prepared in a one-kettle reaction, by reaction of 1 mol of the phenol with 0.3-0.9 mol of sulphonating agent in a strongly acid medium, neutralization of the product to a pH value of 7-8, further reaction with 0.6-2 mols of formaldehyde, reaction with 0.3-0.9 mol of bisulphite and then with 0.8-1.5 mols of formaldehyde at a pH value of 4-8.
Claim 3
Dependent Claim
15 words
Polycondensates according to claim 1, characterised in that they are prepared from mononuclear, nonfused phenols.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-04-19 | 1985-10-19 | 1986-04-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-04-19 | 1989-10-19 | 1990-04-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-04-19 | 1993-10-19 | 1994-04-20 | $7700.00 | Window Closed / Lapsed |