Patent · US Expired

Ventilated cigarette filter

US4807647A · kind A · utility

17Cited by
1References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 17, 1986
Grant dateFeb 28, 1989
Priority date—
Expiry dateOct 17, 2006

Classification

  • Technology area (CPC A)Human Necessities
  • CPC primaryA24D3/043
  • WIPO fieldOther consumer goods
  • WIPO sectorOther fields

Abstract

A cigarette filter comprising longitudinally aligned core components a first of which is air-permeable and of relatively high pressure drop longitudinally of the filter but substantially air-impermeable radially of the filter and a second of which is air-permeable and of relatively low pressure drop longitudinally of the filter, and a common wrap or partial wrap which extends along and around or partially around said core components and provides for ventilation of the filter at a region longitudinally spaced from the first core component.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.