US4193908A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of reducing the viscosity of polyester-alumina _trihydrate dispersions by slight dehydration of trihydrate
Assignee: Alcoa Corp
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Filing: 1978-09-20
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Granted: 1980-03-18
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Expires: 1998-09-20
Abstract
Abstract An improved process for dispersing alumina trihydrate in a polyester resin is disclosed wherein the improvement comprises lowering the viscosity of the polyester-trihydrate dispersion by dehydrating the alumina trihydrate to a reduction in the initial loss on ignition in a range of from 0.2 to 5.0 percent prior to adding the trihydrate to the polyester resin.
Inventors
- 👤 Hsiun P. Hsieh
- 👤 James J. Koenig
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 22:31
CPC Classifications
C; C08; C08K; C08K3/00; C08K3/18; C08K3/20; C08K3/22
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
75 words
An improved method for dispersing alumina trihydrate, having an average particle size less than 15 microns, in a polyester resin comprising: lowering the viscosity of the polyester-trihydrate dispersion, by dehydrating the alumina trihydrate to reduce the initial loss on ignition thereof by from 0.2 to 5.0 percent; and after dehydrating the alumina trihydrate dispersing up to 65 percent alumina trihydrate, based on the total weight of the resin and the trihyrate, with the polyester resin.
Claim 2
Dependent Claim
75 words
An improved method for dispersing alumina trihydrate, having an average particle size less than 15 microns, in a polyester resin comprising: lowering the viscosity of the polyester-trihydrate dispersion, by dehydrating the alumina trihydrate to reduce the initial loss on ignition thereof by from 0.2 to 5.0 percent; and after dehydrating the alumina trihydrate dispersing up to 65 percent alumina trihydrate, based on the total weight of the resin and the trihyrate, with the polyester resin.
Claim 3
Dependent Claim
29 words
A method as set forth in claim 1 wherein the alumina trihydrate is dehydrated to a loss on ignition in a range of from about 34.0 to 34.5 percent.
Claim 4
Dependent Claim
33 words
A method as set forth in claim 1 wherein 50 to 60 percent dehydrated alumina trihydrate based on the total weight of the resin and the trihydrate is dispersed with the polyester resin.
Claim 5
Dependent Claim
31 words
A method as set forth in claim 1 wherein dehydration is accomplished by grinding the alumina trihydrate in a fluid energy mill at an exit temperature of at least 150° C.
Claim 6
Independent Claim
69 words
A method for reducing the viscosity of a dispersion comprising alumina trihydrate and polyester resin, said dispersion containing up to 65 percent alumina trihydrate based on the total weight of the resin and the trihydrate, said alumina trihydrate having an average particle size less than 15 microns, comprising the step of dehydrating the alumina trihydrate to reduce the initial loss on ignition thereof by from 0.2 to 5.0 percent.
Claim 7
Independent Claim
69 words
A method for reducing the viscosity of a dispersion comprising alumina trihydrate and polyester resin, said dispersion containing up to 65 percent alumina trihydrate based on the total weight of the resin and the trihydrate, said alumina trihydrate having an average particle size less than 15 microns, comprising the step of dehydrating the alumina trihydrate to reduce the initial loss on ignition thereof by from 0.2 to 5.0 percent.
Claim 8
Dependent Claim
29 words
A method as set forth in claim 5 wherein the alumina trihydrate is dehydrated to a loss on ignition in a range of from about 34.0 to 34.5 percent.
Claim 9
Dependent Claim
22 words
A method as set forth in claim 5 wherein 50 to 60 percent dehydrated alumina trihydrate is dispersed with the polyester resin.
Claim 10
Dependent Claim
31 words
A method as set forth in claim 5 wherein dehydration is accomplished by grinding the alumina trihydrate in a fluid energy mill at an exit temperature of at least 150° C.
Claim 11
Dependent Claim
58 words
Alumina trihydrate, having an average particle size less than 15 microns, adapted for low viscosity dispersion with up to about 65 percent polyester resin based on the total weight of the resin and the trihydrate, dehydrated such that the loss on ignition is from 0.2 to 5.0 percent lower than the initial loss on ignition of alumina trihydrate.
Claim 12
Dependent Claim
58 words
Alumina trihydrate, having an average particle size less than 15 microns, adapted for low viscosity dispersion with up to about 65 percent polyester resin based on the total weight of the resin and the trihydrate, dehydrated such that the loss on ignition is from 0.2 to 5.0 percent lower than the initial loss on ignition of alumina trihydrate.
Claim 13
Dependent Claim
25 words
Alumina trihydrate as set forth in claim 9 wherein the loss on ignition is in a range of from about 29.8 to about 34.6 percent.
Claim 14
Dependent Claim
25 words
Alumina trihydrate as set forth in claim 9 wherein the loss on ignition is in a range of from about 34.0 to about 34.5 percent.
Claim 15
Dependent Claim
51 words
A thermosetting polyester compound comprising a polyester resin and up to about 65 percent alumina trihydrate, based on the total weight of the resin and trihydrate, said alumina trihydrate dehydrated to reduce the initial percent loss on ignition by about 0.2 to 5.0 percent cured with the aid of a catalyst.
Claim 16
Dependent Claim
51 words
A thermosetting polyester compound comprising a polyester resin and up to about 65 percent alumina trihydrate, based on the total weight of the resin and trihydrate, said alumina trihydrate dehydrated to reduce the initial percent loss on ignition by about 0.2 to 5.0 percent cured with the aid of a catalyst.
Claim 17
Dependent Claim
28 words
A polyester compound as set forth in claim 12 further comprising 10 to 20 percent reinforcing fiberglass strands, based on the total weight of the resin and trihydrate.
Claim 18
Dependent Claim
30 words
A polyester compound as set forth in claim 13 wherein the alumina trihydrate is dehydrated to a loss on ignition in a range of from about 34.0 to 34.5 percent.
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) | 1983-03-18 | 1983-09-17 | 1984-03-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-03-18 | 1987-09-17 | 1988-03-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-03-18 | 1991-09-17 | 1992-03-18 | $7700.00 | Window Closed / Lapsed |