04807619 is referenced by 136 patents and cites 21 patents.

New molded fibrous filtration face masks that are highly resilient and shape-retaining are provided using one or more molded fibrous shaping layers, with a fibrous filtration layer disposed on one side of or between the molded fibrous shaping layers; the molded fibrous shaping layers having a total basis weight of at least 150 g/m2, and at least one of the fibrous shaping layers having an average density over the central area of the face mask of no greater than about 0.2 g/cc, such that at bends of the layer during deformation of the face mask the layer elastically deforms and tends to return to its original thickness and shape when the deforming pressure is removed.

Title
Resilient shape-retaining fibrous filtration face mask
Application Number
6/848757
Publication Number
4807619
Application Date
April 7, 1986
Publication Date
February 28, 1989
Inventor
Alice C Murray
Maplewood
MN, US
Harvey J Berg
St. Paul
MN, US
James F Dyrud
New Richmond
WI, US
Agent
Roger R Tamte
Donald M Sell
Assignee
Minnesota Mining and Manufacturing Company
MN, US
IPC
A62B 7/10
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