US3981845A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High surface area polycondensation polymer particulates based on urea and formaldehyde
Assignee: Novartis AG
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Filing: 1975-05-27
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Granted: 1976-09-21
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Expires: 1995-05-27
Abstract
Abstract A highly dispersed solid non-porous insoluble and infusible urea-formaldehyde condensation polymer in the form of a fluffy white powder, said product having a specific surface area of more than 10 square meters per gram and an average particle size smaller than 5 microns. The product preferably essentially consists of approximately spherical microparticles having substantially uniform size and shape and shows a tendency to form loosely agglomerated structures. These solids are useful as rubber reinforcing agents and as paper pigmentary fillers.
Inventors
- 👤 Alfred Renner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 22:23
CPC Classifications
C; C08; C08G; C08G12/00; C08G12/02; C08G12/04; C08G12/10; C08G12/12; A; A01; A01N; A01N25/00; A01N25/08; A01N25/10; C08J; C08J5/00; C08J5/20; C08J5/22; C08J5/2206; C08J5/2212; C08J9/00; C08J9/28; C08L; C08L21/00; C08J2301/00; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2982
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
33 words
An insoluble, infusible, finely dispersed, non-porous urea-formaldehyde condensation product in particulate form having a specific surface area of more than 10 m 2 /g and an average particle size smaller than 5 microns.
Claim 2
Dependent Claim
33 words
An insoluble, infusible, finely dispersed, non-porous urea-formaldehyde condensation product in particulate form having a specific surface area of more than 10 m 2 /g and an average particle size smaller than 5 microns.
Claim 3
Dependent Claim
25 words
The polycondensation product as claimed in claim 1 in which the specific surface area ranges from about 10 to about 73 square meters per gram.
Claim 4
Dependent Claim
24 words
The polycondensation product as claimed in claim 1 in which the surface area ranges from about 20 to about 30 square meters per gram.
Claim 5
Dependent Claim
23 words
The polycondensation product as claimed in claim 1 in which the surface area ranges from about 25 to about 58 m 2 /g.
Claim 6
Dependent Claim
36 words
An insoluble and infusible finely dispersed non-porous urea-formaldehyde condensation product in the form of a white powder having a specific surface area of 73 square meters per gram and a bulk weight of 11.5 g/100 ml.
Claim 7
Dependent Claim
36 words
An insoluble and infusible finely dispersed non-porous urea-formaldehyde condensation product in the form of a white powder having a specific surface area of 73 square meters per gram and a bulk weight of 11.5 g/100 ml.
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) | 1979-09-21 | 1980-03-22 | 1980-09-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-09-21 | 1984-03-22 | 1984-09-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-09-21 | 1988-03-22 | 1988-09-21 | $7700.00 | Window Closed / Lapsed |