US2963351A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Determination of nitrogen dioxide
Assignee: MSA Safety Inc
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Filing: 1959-11-10
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Granted: 1960-12-06
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Expires: 1979-11-10
Abstract
No abstract record available.
Inventors
- 👤 Evelyn C Stanford
- 👤 Charles A Plantz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:12
CPC Classifications
G; G01; G01N; G01N31/00; G01N31/22; Y; Y10; Y10T; Y10T436/00; Y10T436/17; Y10T436/177692; Y10T436/178459
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
79 words
THAT METHOD OF DETERMINING NITROGEN DIOXIDE IN A GAS WHICH COMPRISES THE STEPS OF PASSING GAS TO BE TESTED THROUGH A BODY OF GRANULAR SOLID CARRYING A REAGENT OF THE GROUP CONSISTING OF N,N,N'',N''-TETRAPHENYLBENZIDINE AND N,N''-DIMETHYL-N,N''-DIPHENYLBENZIDINE TOGETHER WITH AN ACID SELECTED FROM THE GROUP CONSISTING OF SULFURIC ACID, HYDROCHLORIC ACID, PERCHLORIC ACID, TRICHLOROACETIC ACID AND P-TOTULENE SULFONIC ACID, SAID BODY BEING CONFINED WITHIN A TRANSPARENT CONTAINER AND SAID REAGENT BEING CHANGED IN COLOR BY CONTACT WITH SAID NITROGEN DIOXIDE.
Claim 2
Dependent Claim
79 words
THAT METHOD OF DETERMINING NITROGEN DIOXIDE IN A GAS WHICH COMPRISES THE STEPS OF PASSING GAS TO BE TESTED THROUGH A BODY OF GRANULAR SOLID CARRYING A REAGENT OF THE GROUP CONSISTING OF N,N,N'',N''-TETRAPHENYLBENZIDINE AND N,N''-DIMETHYL-N,N''-DIPHENYLBENZIDINE TOGETHER WITH AN ACID SELECTED FROM THE GROUP CONSISTING OF SULFURIC ACID, HYDROCHLORIC ACID, PERCHLORIC ACID, TRICHLOROACETIC ACID AND P-TOTULENE SULFONIC ACID, SAID BODY BEING CONFINED WITHIN A TRANSPARENT CONTAINER AND SAID REAGENT BEING CHANGED IN COLOR BY CONTACT WITH SAID NITROGEN DIOXIDE.
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) | 1963-12-06 | 1964-06-06 | 1964-12-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-12-06 | 1968-06-06 | 1968-12-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-12-06 | 1972-06-06 | 1972-12-06 | $7700.00 | Window Closed / Lapsed |