Patent · US Expired

Container with microporous membrane for dispensing vapor from volatile liquid

US4917301A · kind A · utility

89Cited by
9References
32Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 15, 1988
Grant dateApr 17, 1990
Priority date
Expiry dateNov 15, 2008

Classification

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

Abstract

Volatile substances such as fragrances, perfumes, deodorizers, room freshener compositions and the like are dispensed in vapor phase from a container holding the substance in liquid phase at room temperature under atmospheric pressure. The container has a window covered with a microporous membrane with an active structure formed from a material having a critical surface tension that is below the surface tension of the liquid substance. The active membrane material has a critical surface tension that is below 22 dynes/cm and preferably below 20 dynes/cm while the surface tension of the liquid is at least 22 dynes/cm. One example is an ultraviolet irradiated polymer composition with 0.2 microns nominal pore size.

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