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US3779787A Expired / Lapsed US ⏱️ 0.0 years remaining

Method for producing tobacco-smoke filters

Assignee: Brown and Williamson Holdings Inc
•
Filing: 1971-09-17
•
Granted: 1973-12-18
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Expires: 1991-09-17
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Abstract

Abstract The invention is concerned with a method for the production of tobacco-smoke filters in which an additive is introduced into a rod of tobacco-smoke filter material from a liquid additive bath by means of holes pierced, for example by needles, in the said rod and creating a pressure differential between the rod and bath whereby the additive is drawn into the rod through the holes. The filter material may be an extruded open-cell foam material, such as polyethylene or polypropylene material. The pierced rod may be passed through a bath of the additive in such a manner that the additive is taken into the rod through the holes.

Inventors

  • 👤 F Haslam
  • 👤 H Horsewell
  • 👤 P Gannaway

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 08:45
CPC Classifications
A; A24; A24D; A24D3/00; A24D3/02; A24D3/0204; A24D3/0212; Y; Y10; Y10T; Y10T428/00; Y10T428/24; Y10T428/24273; Y10T428/29; Y10T428/2913; Y10T428/2933

Claims Analysis

Total Claims: 3
Claim 1
Independent Claim 54 words
The method in accordance with claim 1 wherein the rod is pierced at intervals along its length and comprising the further step of sectioning the treated rod into filters, each filter comprising at least one section containing a hole into which additive has been drawn and at least one section which is without additive.
Claim 2
Independent Claim 94 words
A method for the production of tobacco smoke filters from a rod of tobacco smoke filter material comprising the steps of piercing said rod along its length from above and below its longitudinal axis so as to create a plurality of holes therein, submerging only said holes below the longitudinal axis into a liquid additive bath and applying suction means to said holes above the longitudinal axis to create a pressure differential between said rod and said bath whereby said liquid additive is drawn into said rod through said holes to form said filter.
Claim 3
Independent Claim 93 words
A method for the production of tobacco smoke filters from a rod of open-cell foam tobacco smoke filter material comprising the steps of piercing said rod along its length so as to create a plurality of holes therein, subjecting said rod to a first reduced pressure whereby to evacuate said material and thereafter passing said evacuated rod through a liquid additive bath at a second pressure above said first reduced pressure whereby the pressure differential between the interior of said rod and said bath causes said additive to be drawn into said rod.

References Cited (Backward Citations)

US1588617A Cited
US1986319A Cited
US3329544A Cited
US3253967A Cited
US3485208A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1976-12-17 1977-06-18 1977-12-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1980-12-17 1981-06-18 1981-12-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1984-12-17 1985-06-18 1985-12-18 $7700.00 Window Closed / Lapsed

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