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US4291980A
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Styrene-divinylbenzene copolymer and method of manufacture
Assignee: AMCO POLYMERICS Inc 3696-C HAVEN AVENUE REDWOOD CITY CA 94063 A CORP OF
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Filing: 1978-08-14
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Granted: 1981-09-29
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Expires: 1998-08-14
Abstract
Abstract A unique styrene-divinylbenzene copolymer is taught together with its method of manufacture. The novel copolymer has been accepted as a definitive standard in the measurement of turbidity in water.
Inventors
- 👤 James A. Patterson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 16:36
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/17; G01N21/25; G01N21/27; G01N21/274; G01N21/278
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
54 words
A suspension for measuring the turbidity of water comprising a suspension of substantially spherical particles in substantially turbidity-free water, said particles comprising substantially pure styrene-divinylbenzene copolymer wherein said spherical particles are substantially between 0.2 μm to 1.0 μm in diameter and which exhibit substantially pure particle light scatter when suspended is substantially turbidity-free water.
Claim 2
Dependent Claim
54 words
A suspension for measuring the turbidity of water comprising a suspension of substantially spherical particles in substantially turbidity-free water, said particles comprising substantially pure styrene-divinylbenzene copolymer wherein said spherical particles are substantially between 0.2 μm to 1.0 μm in diameter and which exhibit substantially pure particle light scatter when suspended is substantially turbidity-free water.
Claim 3
Dependent Claim
21 words
The suspension of claim 1 wherein the concentration of particles is such as to yield a turbidity reading of 1.0 NTU.
Claim 4
Dependent Claim
21 words
The suspension of claim 1 wherein the concentration of particles is such as to yield a turbidity reading of 5.0 NTU.
Claim 5
Independent Claim
147 words
A method of determining the turbidity of water comprising: A. suspending substantially spherical particles in substantially turbidity-free water wherein said particles comprise substantially pure styrene-divinylbenzene copolymer having a particle size substantially between 0.2μ to 1.0μ in diameter and which exhibits substantially pure particle light scatter when suspended in a substantially turbidity-free media; B. placing said suspension in a substantially transparent cylindrical vessel; C. exposing the side wall of the vessel to a light source perpendicular thereto; D. reading the light which is scattered by said light source perpendicular to the incidence of said light source; E. performing steps C and D on a substantially transparent cylindrical vessel containing water of unknown turbidity; and F. comparing the amount of light scattered from said cylindrical vessel containing the suspended particles of the styrene-divinylbenzene copolymer with the amount of light scattered from said cylindrical vessel containing water of unknown turbidity.
Claim 6
Independent Claim
147 words
A method of determining the turbidity of water comprising: A. suspending substantially spherical particles in substantially turbidity-free water wherein said particles comprise substantially pure styrene-divinylbenzene copolymer having a particle size substantially between 0.2μ to 1.0μ in diameter and which exhibits substantially pure particle light scatter when suspended in a substantially turbidity-free media; B. placing said suspension in a substantially transparent cylindrical vessel; C. exposing the side wall of the vessel to a light source perpendicular thereto; D. reading the light which is scattered by said light source perpendicular to the incidence of said light source; E. performing steps C and D on a substantially transparent cylindrical vessel containing water of unknown turbidity; and F. comparing the amount of light scattered from said cylindrical vessel containing the suspended particles of the styrene-divinylbenzene copolymer with the amount of light scattered from said cylindrical vessel containing water of unknown turbidity.
Claim 7
Dependent Claim
22 words
The method of claim 4 wherein the particles of substantially pure styrene-divinylbenzene copolymer have a specific gravity substantially between 1.04 and 1.06.
Claim 8
Dependent Claim
35 words
The method of claim 4 wherein at least two suspensions of substantially pure styrene-divinylbenzene copolymer particles in substantially turbidity-free water are prepared to a concentration to yield turbidity readings of 1.0 NTU and 5.0 NTU.
References Cited (Backward Citations)
DE1172061B
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-09-28 | 1985-03-30 | 1985-09-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-09-28 | 1989-03-30 | 1989-09-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-09-28 | 1993-03-30 | 1993-09-29 | $7700.00 | Window Closed / Lapsed |