04158440 is referenced by 54 patents and cites 6 patents.

A device for releasing a volatile substance into the environment in a controlled manner comprises a reservoir of substance-absorbent material, for storing the substance, that is encapsulated in an envelope, at least a portion of which comprises a permeable material having porosity at least equal to ultramicroporosity. The permeable envelope portion has a greater affinity for the substance than does the reservoir material. The remainder of the envelope comprises a material impermeable to the substance. Accordingly, the substance permeates through the permeable envelope portion to be released therefrom in vapor form into the environment.

Title
Device for releasing a volatile substance in a controlled manner
Application Number
5/731300
Publication Number
4158440
Application Date
October 12, 1976
Publication Date
June 19, 1979
Inventor
Murray O Meetze Jr
Columbia
SC, US
William E Sullivan
Columbia
SC, US
Agent
St Onge Steward Johnston Reens & Noe
Assignee
The Ridson Manufacturing Company
CT, US
IPC
A61L 9/04
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