US4318709A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Test means, test device and method for determining the ionic strength or specific gravity of a liquid sample
Assignee: Bayer Corp
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Filing: 1980-07-10
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Granted: 1982-03-09
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Expires: 2000-07-10
Abstract
Abstract A test means for determining the ionic strength or specific gravity of an aqueous test sample, the test means comprising a weakly acidic or weakly basic polyelectrolyte which is at least partially neutralized, and an indicator means capable of producing a detectable response to ion exchange between the polyelectrolyte and the sample. The test device comprises a carrier matrix incorporated with the test means, and the method for its use comprises contacting an aqueous test sample with the device and observing a detectable response.
Inventors
- 👤 Richard D. Falb
- 👤 Sisto N. Stiso
- 👤 Yung-Chyung Wang
- 👤 William I. White
- 👤 Rodric H. White-Stevens
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 02:49
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/52; G01N9/00
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
55 words
A test means for determining the ionic strength or specific gravity of an aqueous test sample, said test means comprising a weakly acidic or weakly basic polyelectrolyte polymer, said polymer being at least about 50 percent neutralized, and indicator means capable of producing a detectable response to ion exchange between said polyelectrolyte and said sample.
Claim 2
Dependent Claim
55 words
A test means for determining the ionic strength or specific gravity of an aqueous test sample, said test means comprising a weakly acidic or weakly basic polyelectrolyte polymer, said polymer being at least about 50 percent neutralized, and indicator means capable of producing a detectable response to ion exchange between said polyelectrolyte and said sample.
Claim 3
Dependent Claim
15 words
The test means of claim 1 in which said polymer is a weakly acidic polyelectrolyte.
Claim 4
Dependent Claim
15 words
The test means of claim 1 in which said polymer is a weakly basic polyelectrolyte.
Claim 5
Dependent Claim
27 words
The test means of claim 1 in which said polyelectrolyte is poly(acrylic acid), poly(maleic acid), maleic acidvinylmethyl ether copolymer, poly(methacrylic acid), styrenemaleic acid copolymer, poly(vinylamine), or poly(4-vinylpyridine).
Claim 6
Dependent Claim
22 words
The test means of any one of claims 1-4 in which said polyelectrolyte polymer is about 75 to about 95 percent neutralized.
Claim 7
Dependent Claim
19 words
The test means of any one of claims 1-4 in which said indicator means is a pH indicator substance.
Claim 8
Dependent Claim
31 words
The test means of any one of claims 1-4 in which said indicator means is a pH indicator substance, and said polyelectrolyte polymer is about 75 to about 95 percent neutralized.
Claim 9
Dependent Claim
24 words
The test means of claim 1 in which said polyelectrolyte is a methylvinylether-maleic acid copolymer, and in which said indicator means is bromothymol blue.
Claim 10
Dependent Claim
34 words
A test device for determining the ionic strength or specific gravity of an aqueous test sample, said device comprising a carrier matrix incorporated with the test means of any of claims 1-4 or 8.
Claim 11
Dependent Claim
30 words
A test device for determining the ionic strength or specific gravity of an aqueous test sample, said device comprising a carrier matrix incorporated with the test means of claim 5.
Claim 12
Dependent Claim
30 words
A test device for determining the ionic strength or specific gravity of an aqueous test sample, said device comprising a carrier matrix incorporated with the test means of claim 6.
Claim 13
Dependent Claim
30 words
A test device for determining the ionic strength of specific gravity of an aqueous test sample, said device comprising a carrier matrix incorporated with the test means of claim 7.
Claim 14
Independent Claim
37 words
A method for determining the ionic strength or specific gravity of an aqueous test sample, said method comprising contacting said sample with the test means of any of claims 1-4 or 8 and observing a detectable response.
Claim 15
Dependent Claim
33 words
A method for determining the ionic strength or specific gravity of an aqueous test sample, said method comprising contacting said sample with the test means of claim 5 and observing a detectable response.
Claim 16
Dependent Claim
33 words
A method for determining the ionic strength or specific gravity of an aqueous test sample, said method comprising contacting said sample with the test means of claim 6 and observing a detectable response.
Claim 17
Dependent Claim
33 words
A method for determining the ionic strength or specific gravity of an aqueous test sample, said method comprising contacting said sample with the test means of claim 7 and observing a detectable response.
Claim 18
Dependent Claim
32 words
A method for determining the ionic strength or specific gravity of an aqueous test sample, said method comprising contacting said sample with the device of claim 9 and observing a detectable response.
Claim 19
Dependent Claim
32 words
A method for determining the ionic strength or specific gravity of an aqueous test sample, said method comprising contacting said sample with the device of claim 10 and observing a detectable response.
Claim 20
Dependent Claim
32 words
A method for determining the ionic strength or specific gravity of an aqueous test sample, said method comprising contacting said sample with the device of claim 11 and observing a detectable response.
Claim 21
Dependent Claim
32 words
A method of determining the ionic strength or specific gravity of an aqueous test sample, said method comprising contacting said sample with the device of claim 12 and observing a detectable response.
Claim 22
Independent Claim
56 words
A method for preparing a test device for determining the ionic strength or specific gravity of an aqueous test sample, said method comprising the steps of neutralizing at least 50 percent of the ionizable groups of a weakly acidic or weakly basic polyelectolyte polymer, and incorporating said polymer and a pH indicator with a carrier matrix.
Claim 23
Independent Claim
56 words
A method for preparing a test device for determining the ionic strength or specific gravity of an aqueous test sample, said method comprising the steps of neutralizing at least 50 percent of the ionizable groups of a weakly acidic or weakly basic polyelectolyte polymer, and incorporating said polymer and a pH indicator with a carrier matrix.
Claim 24
Dependent Claim
17 words
The method of claim 21 wherein said polyelectrolyte polymer is about 75 to about 95 percent neutralized.
Claim 25
Independent Claim
42 words
The method of claims 21 or 22 wherein said polymer and said pH indicator are incorporated with said matrix by combination thereof with a suitable solvent to form an impregnation mixture, and said carrier matrix is contacted with said mixture and dried.
Claim 26
Independent Claim
93 words
A method for preparing a test device for determining the ionic strength or specific gravity of an aqueous test sample, said method comprising the steps of preparing an aqueous solution of a copolymer of maleic acid and methylvinylether, adding an aqueous solution of a base to said copolymer solution sufficient to neutralize at least 50 percent of the acid groups of said copolymer. contacting a carrier matrix with the partly neutralized polymer solution thereby incorporating said polymer with said matrix, drying the polymer-incorporated matrix, and incorporating a pH indicator with said dried matrix.
Claim 27
Independent Claim
93 words
A method for preparing a test device for determining the ionic strength or specific gravity of an aqueous test sample, said method comprising the steps of preparing an aqueous solution of a copolymer of maleic acid and methylvinylether, adding an aqueous solution of a base to said copolymer solution sufficient to neutralize at least 50 percent of the acid groups of said copolymer. contacting a carrier matrix with the partly neutralized polymer solution thereby incorporating said polymer with said matrix, drying the polymer-incorporated matrix, and incorporating a pH indicator with said dried matrix.
Claim 28
Dependent Claim
40 words
The method of claim 24 wherein said pH indicator is bromothymol blue and said indicator is incorporated with said dried polymer-incorporated matrix by preparing a solution of said indicator in methanol, and contacting said polymer-incorporated matrix with said indicator solution.
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) | 1985-03-08 | 1985-09-07 | 1986-03-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-03-08 | 1989-09-07 | 1990-03-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-03-08 | 1993-09-07 | 1994-03-09 | $7700.00 | Window Closed / Lapsed |