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US4391930A
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Stabilized suspension of glass bubbles in an aqueous dispersion of tetrafluoroethylene polymer
Assignee: EIDP Inc
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Filing: 1982-02-11
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Granted: 1983-07-05
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Expires: 2002-02-11
Abstract
Abstract Hollow glass bubble-containing aqueous dispersions of tetrafluoroethylene polymer having good shelf life are provided, said dispersions also containing nonionic surfactant and water soluble electrolyte.
Inventors
- 👤 Allan H. Olson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 16:11
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/32; C08J3/00; C08J3/02; C08J3/03; C08J2327/00; C08J2327/02; C08J2327/12; C08J2327/18
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
115 words
A stabilized suspension of glass bubbles in an aqueous dispersion of tetrafluoroethylene polymer, which suspension comprises (a) water having dispersed therein 45-75% by weight, based on water, of a tetrafluoroethylene polymer having a melt viscosity of at least 1×10 9 poises at 380° C., (b) 5 to 10% by weight, based on polymer, of a nonionic surfactant, (c) 0.1 to 0.5% by weight, based on water and polymer, of a water-soluble electrolyte, and (d) 2 to 8% by weight, based on polymer, of glass bubbles having a density between 0.20 and 0.40 g/ml and an average size between 20 and 130 micron, said dispersion having a viscosity between 135 and 300 cps at 25° C.
Claim 2
Dependent Claim
115 words
A stabilized suspension of glass bubbles in an aqueous dispersion of tetrafluoroethylene polymer, which suspension comprises (a) water having dispersed therein 45-75% by weight, based on water, of a tetrafluoroethylene polymer having a melt viscosity of at least 1×10 9 poises at 380° C., (b) 5 to 10% by weight, based on polymer, of a nonionic surfactant, (c) 0.1 to 0.5% by weight, based on water and polymer, of a water-soluble electrolyte, and (d) 2 to 8% by weight, based on polymer, of glass bubbles having a density between 0.20 and 0.40 g/ml and an average size between 20 and 130 micron, said dispersion having a viscosity between 135 and 300 cps at 25° C.
Claim 3
Dependent Claim
15 words
The dispersion of claim 1 wherein the polymer concentration is 55 to 65% by wt.
Claim 4
Dependent Claim
10 words
The dispersion of claim 1 wherein the polymer is polytetrafluoroethylene.
Claim 5
Dependent Claim
16 words
The dispersion of claim 1 wherein the surfactant concentration is from 5.0 to 8.0% by weight.
Claim 6
Dependent Claim
13 words
The dispersion of claim 1 wherein said electrolyte is an inorganic barium salt.
Claim 7
Dependent Claim
12 words
The dispersion of claim 1 wherein said electrolyte is an ammonium citrate.
Claim 8
Dependent Claim
18 words
The dispersion of claim 1 wherein the nonionic surfactant is an ethoxylated aliphatic alcohol or ethoxylated alkyl phenol.
Claim 9
Dependent Claim
26 words
The dispersion of claim 1, 2, 3, 4, 5, 6 or 7 wherein the glass bubbles have a density of between about 0.36 and 0.39 g/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) | 1986-07-04 | 1987-01-03 | 1987-07-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-07-04 | 1991-01-03 | 1991-07-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-07-04 | 1995-01-03 | 1995-07-05 | $7700.00 | Window Closed / Lapsed |