EP0241221A1
Expired / Lapsed
EP
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Resilient shape-retaining fibrous filtration face mask
Assignee: 3M Co
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Filing: 1987-04-02
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Granted: —
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Expires: 2007-04-02
Abstract
Abstract Resilient shape-retaining face mask (10) comprising molded, bonded, high-basis-weight, lofty fibrous shaping layers (15, 17) and a fibrous filtration layer (16).
Inventors
- 👤 Mining And Manufactu Minnesota
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 05:48
CPC Classifications
A; A62; A62B; A62B18/00; B; B32; B32B; B32B5/00; B32B5/22; B32B5/24; B32B5/26; A41; A41D; A41D13/00; A41D13/05; A41D13/11; A41D13/1107; A41D13/1138; A41D13/1146; A62B23/00; A62B23/02; A62B23/025; B01; B01D; B01D39/00; B01D39/14; B01D39/16; B01D39/1607; B01D39/1623; B01D39/163; B32B38/00; B32B38/0036; B32B2555/00
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
161 words
A resilient cup-shaped filtration face mask adapted to cover the mouth and nose of a wearer of the mask comprising: a) one or more molded fibrous shaping layers that comprise fibers bonded to one another and to other included fibers at intersecting points throughout the layer; b) a fibrous filtration layer disposed on one side of or between said molded fibrous shaping layers, the filtration layer removing a higher percentage of particles from a gaseous stream than the shaping layers remove; characterized in that said molded fibrous shaping layers have a total basis weight of at least about 150 g/m², and at least one of said fibrous shaping layers have 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.
Claim 2
Dependent Claim
161 words
A resilient cup-shaped filtration face mask adapted to cover the mouth and nose of a wearer of the mask comprising: a) one or more molded fibrous shaping layers that comprise fibers bonded to one another and to other included fibers at intersecting points throughout the layer; b) a fibrous filtration layer disposed on one side of or between said molded fibrous shaping layers, the filtration layer removing a higher percentage of particles from a gaseous stream than the shaping layers remove; characterized in that said molded fibrous shaping layers have a total basis weight of at least about 150 g/m², and at least one of said fibrous shaping layers have 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.
Claim 3
Dependent Claim
26 words
A face mask of claim 1 in which fibers having an average denier of at least 10 are included in at least one fibrous shaping layer.
Claim 4
Dependent Claim
43 words
A face mask of claim 1 which includes at least two molded fibrous shaping layers, one of which comprises fibers having an average denier of at least 10 and the other of which comprises fibers having an average denier of less than 10.
Claim 5
Dependent Claim
23 words
A face mask of any of claims 1-3 in which at least one of the molded fibrous shaping layers includes crimped single-component fibers.
Claim 6
Dependent Claim
22 words
A face mask of claim 4 in which the crimped single-component fibers comprise fibers having an average denier of at least 10.
Claim 7
Dependent Claim
35 words
A face mask of any of claims 1-5 in which at least one shaping layer was heated and conformed into the stated cup shape after it had been first heated to cause bonding between fibers.
Claim 8
Dependent Claim
46 words
A face mask of any of claims 1-6 in which the fibrous shaping layers are molded under heat and pressure while assembled in face-to-face contact with the filtration layer, and the shaping and filtration layers are conformed into contact with one another over their full interfaces.
Claim 9
Dependent Claim
52 words
A face mask of any of claims 1-7 in which at least one molded fibrous shaping layer has a patterned variation in thickness such that bands of raised thickness and greater loft are disposed at the center of the mask and alternate with bands of lesser thickness in a generally parallel pattern.
Claim 10
Dependent Claim
26 words
A face mask of any of claims 1-8 which exhibits a resistance to 5-centimeter deformation in the test described herein of at least about 5 Newtons.
Claim 11
Dependent Claim
23 words
A face mask of any of claims 1-9 which exhibits recovery to its original shape after 5-centimeter deformation in the test described herein.
Claim 12
Dependent Claim
24 words
A face mask of any of claims 1-10 in which the shaping layers have a total basis weight of at least about 200 g/m².
Claim 13
Dependent Claim
23 words
A face mask of any of claims 1-11 in which the filtration layer comprises fibers that average less than 10 micrometers in diameter.
Claim 14
Dependent Claim
74 words
A face mask of any of claims 1-12 in which at least one of the fibrous shaping layers comprises bicomponent fibers having first and second components extending over the length of the fibers, the first component melting at a temperature lower than the second component and the fibers being bonded to one another and to other included fibers at intersection points throughout the layer by adhesion of the first component to the intersecting fibers.
Claim 15
Dependent Claim
26 words
A face mask of claim 13 in which bicomponent fibers comprise at least about 75 weight-percent of at least one of the molded fibrous shaping layers.
Claim 16
Dependent Claim
26 words
A face mask of any of claims 1-14 in which at least one molded fibrous shaping layer comprises crimped fibers of at least about 50 denier.
References Cited (Backward Citations)
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