Claims
- 1. An aqueous dispersion comprising > 18% by weight of a melt-processable bipolymer consisting essentially of units of tetrafluoroethylene and a fluoroalkyl perfluorovinyl ether and having a number-average particle size of at most 50 nm.
- 2. A dispersion as claimed in claim 1, comprising from 19.5 to 25% by weight of the polymer.
- 3. A dispersion as claimed in claim 1 having a number-average particle size of at most 40 nm.
- 4. A dispersion as claimed in claim 1 having a number-average particle size of below 30 nm.
- 5. A dispersion as claimed in claim 1, wherein the fluoroalkyl perfluorovinyl ether units of said bipolymer consist essentially of units of a fluoroalkyl perfluorovinyl ether of the formula X--(CF.sub.2)--.sub.n O--CF.dbd.CF.sub.2, in which X is hydrogen, chlorine or fluorine and n is from 1 to 6.
- 6. A dispersion as claimed in claim 5, wherein X is fluorine and n is from 1 to 3.
- 7. A porous substrate coated with a dispersion as claimed in claim 1.
- 8. An aqueous dispersion consisting essentially of particles with a number average particle size less than 50 nm which adhere to a surface when coated thereon, said aqueous dispersion consisting essentially of >18% by weight of melt-processable bipolymer particles consisting essentially of a tetrafluoro-ethylene/fluoroalkyl perfluorovinyl ether bipolymer.
- 9. The aqueous dispersion as claimed in claim 8, wherein said bipolymer contains 3.8 to 4.9% by weight perfluoropropyl perfluorovinyl ether units.
Priority Claims (1)
Number |
Date |
Country |
Kind |
43 05 619.0 |
Feb 1993 |
DEX |
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Parent Case Info
This application is a continuation of our application Ser. No. 08/199,502, filed Feb. 22, 1994, now abandoned.
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Continuations (1)
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Number |
Date |
Country |
Parent |
199502 |
Feb 1994 |
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