Patent · US Expired

Membrane-gel diffusion device

US4809912A · kind A · utility

53Cited by
8References
45Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 27, 1987
Grant dateMar 7, 1989
Priority date
Expiry dateMar 27, 2007

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S261/88
  • WIPO fieldMedical technology
  • WIPO sectorInstruments

Abstract

A method for the fabrication of a continuous action reservoir type air freshening device is described. The device is characterized by the use of an evaporation rate controlling porous membrane which is in intimate contact and completely covers the exposed surface of an erodible gel-type of solid perfume composition. The fragranced gel is enclosed in a container, one end of which is open and over which is affixed the porous membrane. One side of this membrane is exposed to the atmosphere; the other side intimately contacts the solid reservoir consisting of the fragrance gel. Transmission of the volatile fragrance and carrier agents to the surrounding environment through the porous membrane matrix occurs as a function of an evaporative process. The membrane permits only a limited penetration, if any by the gel solution, i.e. in the liquid state, but is sufficiently permeable to the gel solution to establish physical attachment between the solidified gel and the membrane.

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