US2792006A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Filters and filter material for use in filtering tobacco smoke
Assignee: Individual
•
Filing: 1955-05-23
•
Granted: 1957-05-14
•
Expires: 1975-05-23
Abstract
No abstract record available.
Inventors
- 👤 Marek Jan Ivo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 15:35
CPC Classifications
A; A24; A24D; A24D3/00; A24D3/06; A24D3/16; A24D3/163
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
74 words
FILTER MATERIAL FOR USE IN FILTERING TOBACCO SMOKE COMPRISING CELLULOSIC MATERIAL TO EFFECT MECHANICAL FILTERING OF THE SMOKE, AND CARBON IN COMBINATION THEREWITH, IN A FORM PENETRABLE BY SMOKE AND OF AT LEAST 96% PURITY, THE CARBON BEING OBTAINED BY A WET PROCESS FROM LIGNIN PRODUCED IN THE MANUFACTURE OF PAPER BY THE SODA PROCESS AND HEATED WITH CONCENTRATED SULPHURIC ACID AT A TEMPERATURE OF OVER 220*C. THE CARBON BEING TREATED SUBSEQUENTLY WITH STEAM.
Claim 2
Dependent Claim
74 words
FILTER MATERIAL FOR USE IN FILTERING TOBACCO SMOKE COMPRISING CELLULOSIC MATERIAL TO EFFECT MECHANICAL FILTERING OF THE SMOKE, AND CARBON IN COMBINATION THEREWITH, IN A FORM PENETRABLE BY SMOKE AND OF AT LEAST 96% PURITY, THE CARBON BEING OBTAINED BY A WET PROCESS FROM LIGNIN PRODUCED IN THE MANUFACTURE OF PAPER BY THE SODA PROCESS AND HEATED WITH CONCENTRATED SULPHURIC ACID AT A TEMPERATURE OF OVER 220*C. THE CARBON BEING TREATED SUBSEQUENTLY WITH STEAM.
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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) | 1960-05-13 | 1960-11-12 | 1961-05-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-05-13 | 1964-11-12 | 1965-05-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-05-13 | 1968-11-12 | 1969-05-14 | $7700.00 | Window Closed / Lapsed |