US4301027A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Silica gels incorporating insolubilized reagents
Assignee: Draegerwerk AG and Co KGaA
•
Filing: 1979-07-03
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Granted: 1981-11-17
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Expires: 1999-07-03
Abstract
Abstract A dried silica gel containing a reagent in insolubilized form which reagent is normally soluble, especially a dried silica gel containing an insolubilized form of a normally soluble colorimetric analytical agent and a method of preparing such dried silica gel by hydrolyzing a silane having from 1 to 4 alkoxy groups in a homogeneous phase in the presence of a reagent which is normally soluble in a solvent, recovering the resultant gel and drying the same.
Inventors
- 👤 Alfred Blumcke
- 👤 Peter Fischer
- 👤 Hans-Joachim Vahlensieck
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 21:30
CPC Classifications
B; B01; B01J; B01J20/00; B01J20/02; B01J20/10; B01J20/103; G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/52; Y; Y10; Y10T; Y10T436/00; Y10T436/10
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
49 words
A process for preparing a dried silica gel containing insolubilized reactive form a reagent which is normally soluble which comprises hydrolyzing a silane having from 1 to 4 alkoxy groups in homogeneous phase in the presence of a soluble reagent, recovering the resultant silica gel and drying the same.
Claim 2
Dependent Claim
49 words
A process for preparing a dried silica gel containing insolubilized reactive form a reagent which is normally soluble which comprises hydrolyzing a silane having from 1 to 4 alkoxy groups in homogeneous phase in the presence of a soluble reagent, recovering the resultant silica gel and drying the same.
Claim 3
Dependent Claim
14 words
A process according to claim 1 wherein the reagent is a colorimetric analytical reagent.
Claim 4
Dependent Claim
28 words
A process according to claim 2 wherein said reagent is a soluble organic reagent, an inorganic salt of the type used in analytical chemistry or an organometallic compound.
Claim 5
Dependent Claim
24 words
A process according to claim 3 wherein said reagent is one which reacts with a metal in a test solution with evolution of color.
Claim 6
Dependent Claim
24 words
A process according to claim 4 wherein the silane which has 1 to 4 alkoxy groups is a tetraalkylorthosilicate or a condensation product thereof.
Claim 7
Dependent Claim
18 words
A process according to claim 3 wherein the hydrolysis is carried out in an alkaline or acidic medium.
Claim 8
Dependent Claim
105 words
A process according to claim 3 wherein the silane having 1 to 4 alkoxy groups is an alkylalkoxysilane of the formula (RO).sub.4-n Si(R'X).sub.n wherein n=1-3, R is an alkyl radical of from 1 to 4 carbon atoms, R' is an alkylene moiety having 1 to 6 carbon atoms and X represents hydrogen, ##STR3## wherein R" is H, CH 3 , or C 2 H 5 , Z 1 =H or --(CH 2 ) m --NH 2 (m=2-4) or --[(CH 2 ) p NH--(CH 2 ) p ]NH 2 (each p=1 or 2) and Z 2 may be one of the Z 1 moieties or H.
Claim 9
Dependent Claim
12 words
A process according to claim 7, wherein n=1 and X is hydrogen.
Claim 10
Dependent Claim
44 words
A composition consisting essentially of a dried silica gel containing in insolubilized form a normally soluble reagent which retains its reactivity, said reagent in said silica gel being insoluble to solvents in which it is normally soluble prepared by the process of claim 7.
Claim 11
Dependent Claim
12 words
A composition according to claim 9, wherein n=1 and X is hydrogen.
Claim 12
Dependent Claim
53 words
A composition consisting essentially of dried silica gel containing in insolubilized form a normally soluble reagent which retains its reactivity, said reagent in said silica gel being insoluble to solvents in which it is normally soluble prepared by the process of claim 1 employing as the silane a silane having 4 alkoxy groups.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-11-16 | 1985-05-18 | 1985-11-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-11-16 | 1989-05-18 | 1989-11-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-11-16 | 1993-05-18 | 1993-11-17 | $7700.00 | Window Closed / Lapsed |