Patent US3675541A successfully refreshed from Google Patents.
US3675541A
Expired / Lapsed
US
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Process of making a tobacco smoke filter from a split film of cellulose acetate
Assignee: Mitsubishi Chemical Corp
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Filing: 1970-06-02
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Granted: 1972-07-11
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Expires: 1990-06-02
Abstract
Abstract A cellulose acetate film is subjected to stretch operations which are carried out under conditions such that highly oriented molecular chains are created therein and then to splitting whereby a netlike configuration composed of numerous stem fibers and branch fibers linking adjacent stem fibers is obtained. A tobacco smoke filter is formed from the split acetate film after additional treatments including crimping.
Inventors
- 👤 Soichi Tokitomo
- 👤 Masakazu Honda
- 👤 Fumio Nakayama
- 👤 Keisiro Ueno
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 15:13
CPC Classifications
A; A24; A24D; A24D3/00; A24D3/06; A24D3/08; A24D3/10; Y; Y10; Y10S; Y10S264/00; Y10S264/47; Y10S264/48
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
36 words
Process according to claim 1 in which said split film is then crimped, formed into a cylindrically shaped mass, wrapped with paper and cut transversely into a length suitable for use as a cigarette filter rod.
Claim 2
Dependent Claim
24 words
Process according to claim 1 in which the first stage of said stretching is carried out in an aqueous solution containing a swelling agent.
Claim 3
Dependent Claim
40 words
Process for manufacturing a filter for tobacco smoke according to claim 1, in which a plurality of said split films are superimposed on each other and said plurality of superimposed split films are crimped and formed into a cylindrical mass.
Claim 4
Dependent Claim
36 words
Process for manufacturing a filter for tobacco smoke according to claim 1, in which a bonding agent is added to said split film and the split film is crimped and formed into a cylindrically shaped mass.
Claim 5
Dependent Claim
36 words
Process for manufacturing a filter for tobacco smoke according to claim 1, in which an absorbent is added to said split film and then said split film is crimped and formed into a cylindrically shaped mass.
Claim 6
Dependent Claim
45 words
Process for manufacturing a filter for tobacco smoke according to claim 1, in which an additional substance to improve the taste or smell of tobacco is added to said split film and then said split film is crimped and formed into a cylindrically shaped mass.
References Cited (Backward Citations)
US2306666A
Cited
US3165563A
Cited
US3468461A
Cited
US3336174A
Cited
US3344796A
Cited
US3398441A
Cited
GB1149115A
Cited
US3353542A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-07-11 | 1976-01-10 | 1976-07-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-11 | 1980-01-10 | 1980-07-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-11 | 1984-01-10 | 1984-07-11 | $7700.00 | Window Closed / Lapsed |