US5645057A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Meltblown barrier webs and processes of making same
Assignee: Fitesa Simpsonville Inc
•
Filing: 1996-07-02
•
Granted: 1997-07-08
•
Expires: 2016-07-02
Abstract
Abstract A nonwoven disposable face mask includes a filtration layer formed of a plurality of thermoplastic microfine meltblown microfibers having an average fiber diameter of less than 1.5 microns. The filtration layer also has a basis weight of less than ten grams per square meter. The resultant face mask provides improved wearer comfort and barrier and filtration properties.
Inventors
- 👤 James M. Watt
- 👤 Deborah K. Lickfield
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 01:43
CPC Classifications
A; A41; A41D; A41D13/00; A41D13/05; A41D13/11; A62; A62B; A62B23/00; A62B23/02; A62B23/025; D; D04; D04H; D04H1/00; D04H1/40; D04H1/54; D04H1/542; D04H1/544; D04H1/559; D04H1/56; Y; Y10; Y10S; Y10S264/00; Y10S264/48; Y10S428/00; Y10S428/903; Y10S55/00; Y10S55/39; Y10T; Y10T428/00; Y10T428/249921; Y10T428/249953; Y10T428/249962; Y10T428/249964; Y10T428/249978; Y10T428/24998; Y10T428/26; Y10T428/268; Y10T442/00; Y10T442/60; Y10T442/608; Y10T442/614; Y10T442/621; Y10T442/659; Y10T442/66; Y10T442/68
Claims Analysis
Total Claims: 33
Claim 1
Independent Claim
105 words
A face mask for covering a portion of the face of a wearer of the mask, said face mask comprising: an absorbent facing layer for contacting a portion of the face of a wearer of the mask; a cover layer; and an inner filtration layer sandwiched between said cover layer and said absorbent layer, said filtration layer having a basis weight of less than ten grams per square meter and comprising a plurality of thermoplastic microfine fibers having an average fiber diameter of less than 1.5 microns which were melt blown from a polymer having a melt flow rate greater than about 1000 g/10 min.
Claim 2
Dependent Claim
105 words
A face mask for covering a portion of the face of a wearer of the mask, said face mask comprising: an absorbent facing layer for contacting a portion of the face of a wearer of the mask; a cover layer; and an inner filtration layer sandwiched between said cover layer and said absorbent layer, said filtration layer having a basis weight of less than ten grams per square meter and comprising a plurality of thermoplastic microfine fibers having an average fiber diameter of less than 1.5 microns which were melt blown from a polymer having a melt flow rate greater than about 1000 g/10 min.
Claim 3
Dependent Claim
29 words
The face mask according to claim 1, wherein said filtration layer comprises a plurality of thermoplastic microfine fibers having an average fiber diameter between about 0.5 and 1.5 microns.
Claim 4
Dependent Claim
29 words
The face mask according to claim 1, wherein said filtration layer comprises a plurality of thermoplastic microfine fibers having an average fiber diameter between about 0.8 and 1.3 microns.
Claim 5
Dependent Claim
23 words
The face mask according to claim 1, wherein said filtration layer has a basis weight between 1 and 5 grams per square meter.
Claim 6
Dependent Claim
31 words
The face mask according to claim 1, wherein said thermoplastic microfine fibers are formed from a polymer selected from the group consisting of polyolefins, polyesters, polyamides, and copolymers and blends thereof.
Claim 7
Dependent Claim
21 words
The face mask according to claim 1, further comprising means for removably attaching the mask to the face of the wearer.
Claim 8
Dependent Claim
28 words
The face mask according to claim 1, wherein said thermoplastic microfine fibers are formed of a polymer having a melt flow rate of greater than 1,200 g/10 min.
Claim 9
Dependent Claim
13 words
The face mask according to claim 1, wherein said thermoplastic polymer is polypropylene.
Claim 10
Dependent Claim
22 words
The face mask according to claim 1, wherein the change in pressure drop across said filtration layer is from 0.3 to 0.8.
Claim 11
Dependent Claim
17 words
The face mask according to claim 1, wherein said outer cover layer is a hydrophobic nonwoven web.
Claim 12
Dependent Claim
16 words
The face mask according to claim 1, wherein said absorbent layer is a hydrophilic nonwoven web.
Claim 13
Dependent Claim
39 words
The face mask according to claim 1, wherein said face mask comprises a plurality of discrete thermal bonds about the periphery thereof bonding the absorbent layer, the filtration layer and the cover layer to form a coherent laminate fabric.
Claim 14
Dependent Claim
126 words
A face mask for covering a portion of the face of a wearer of the mask, said face mask comprising: an absorbent facing layer for contacting a portion of the face of a wearer of the mask; a hydrophobic cover layer; and an inner filtration layer having a basis weight of 1 to 5 grams per square meter and comprising a plurality of microfine microfibers having an average fiber diameter of 0.5 to 1.5 microns formed from a polypropylene having a melt flow rate of greater than 1,000 g/10 min., said filtration layer exhibiting a pressure drop across said filtration layer from 0.3 to 0.8, said filtration layer sandwiched between and bonded to said cover layer and said absorbent layer to form a coherent face mask.
Claim 15
Dependent Claim
126 words
A face mask for covering a portion of the face of a wearer of the mask, said face mask comprising: an absorbent facing layer for contacting a portion of the face of a wearer of the mask; a hydrophobic cover layer; and an inner filtration layer having a basis weight of 1 to 5 grams per square meter and comprising a plurality of microfine microfibers having an average fiber diameter of 0.5 to 1.5 microns formed from a polypropylene having a melt flow rate of greater than 1,000 g/10 min., said filtration layer exhibiting a pressure drop across said filtration layer from 0.3 to 0.8, said filtration layer sandwiched between and bonded to said cover layer and said absorbent layer to form a coherent face mask.
Claim 16
Dependent Claim
106 words
A process for the manufacture of a face mask for covering a portion of the face of a wearer of the mask, the process comprising: forming from a polymer having a melt flow rate greater than about 1000 g/10 min. a meltblown web having a basis of weight of less than 10 grams per square meter and comprising a plurality of thermoplastic microfine meltblown fibers having an average fiber diameter of less than 1.5 microns; sandwiching said meltblown nonwoven web between opposing nonwoven webs to form a laminate fabric; and bonding said opposing nonwoven webs and said meltblown web together to form a coherent laminate fabric.
Claim 17
Dependent Claim
106 words
A process for the manufacture of a face mask for covering a portion of the face of a wearer of the mask, the process comprising: forming from a polymer having a melt flow rate greater than about 1000 g/10 min. a meltblown web having a basis of weight of less than 10 grams per square meter and comprising a plurality of thermoplastic microfine meltblown fibers having an average fiber diameter of less than 1.5 microns; sandwiching said meltblown nonwoven web between opposing nonwoven webs to form a laminate fabric; and bonding said opposing nonwoven webs and said meltblown web together to form a coherent laminate fabric.
Claim 18
Dependent Claim
36 words
The process according to claim 14, wherein the step of forming a meltblown web comprises forming a meltblown web comprising a plurality of thermoplastic microfine fibers having an average fiber diameter between 0.5 and 1.5 microns.
Claim 19
Dependent Claim
36 words
The process according to claim 14, wherein the step of forming a meltblown web comprises forming a meltblown web comprising a plurality of thermoplastic microfine fibers having an average fiber diameter between 0.8 and 1.3 microns.
Claim 20
Dependent Claim
31 words
The process according to claim 14, wherein the step of forming a meltblown web comprises forming a meltblown web having a basis weight between 1 and 5 grams per square meter.
Claim 21
Dependent Claim
39 words
The process according to claim 14, wherein the step of forming a meltblown nonwoven web comprises forming a meltblown nonwoven web formed of a polymer selected from the group consisting of polyolefins, polyesters, polyamides, and blends and copolymers thereof.
Claim 22
Dependent Claim
34 words
The process according to claim 14, wherein the step of forming a meltblown nonwoven web comprises forming a meltblown web from a polymer having a melt flow rate of greater than 1,200 g/10 min.
Claim 23
Dependent Claim
31 words
The process according to claim 14, wherein the step of forming a meltblown web comprises forming a meltblown web having a pressure drop across said meltblown web from 0.3 to 0.8.
Claim 24
Dependent Claim
20 words
The process according to claim 14, wherein the step of bonding said laminate fabric comprises thermally bonding said laminate fabric.
Claim 25
Dependent Claim
33 words
The process according to claim 14, wherein the step of sandwiching said meltblown layer between outer opposing layers comprises sandwiching said meltblown layer between a hydrophobic cover layer and a hydrophilic absorbent layer.
Claim 26
Dependent Claim
86 words
A process for manufacturing a meltblown barrier layer, comprising: extruding a molten thermoplastic polymer, having a melt flow rate greater than about 1000 g/10 min. through capillaries to form filamentary streams; attenuating and breaking said filamentary streams with a high velocity heated gas to form a plurality of microfine fibers having an average fiber diameter of less than 1.5 microns; and collecting said microfine fibers on a collection surface to form a nonwoven web having a basis weight of less than 10 grams per square meter.
Claim 27
Dependent Claim
86 words
A process for manufacturing a meltblown barrier layer, comprising: extruding a molten thermoplastic polymer, having a melt flow rate greater than about 1000 g/10 min. through capillaries to form filamentary streams; attenuating and breaking said filamentary streams with a high velocity heated gas to form a plurality of microfine fibers having an average fiber diameter of less than 1.5 microns; and collecting said microfine fibers on a collection surface to form a nonwoven web having a basis weight of less than 10 grams per square meter.
Claim 28
Dependent Claim
30 words
The process according to claim 23, wherein said molten thermoplastic polymer is polypropylene and said high velocity heated gas is heated to a temperature from 560° F. to 650° F.
Claim 29
Dependent Claim
24 words
The process according to claim 24, wherein said high velocity heated gas is heated to a temperature of between 575° F. and 640° F.
Claim 30
Dependent Claim
27 words
The process according to claim 24, wherein said high velocity heated gas has an air velocity of about 25 to 30 cubic feet per minute per inch.
Claim 31
Dependent Claim
21 words
The process according to claim 23, wherein said molten polymer has a melt flow rate of greater than 1,200 g/10 min.
Claim 32
Dependent Claim
20 words
The process according to claim 23, wherein said microfine fibers have an average fiber diameter between 0.5 and 1.5 microns.
Claim 33
Dependent Claim
22 words
The process according to claim 23, wherein said meltblown web has a basis weight between 1 and 5 grams per square meter.
References Cited (Backward Citations)
US4041203A
Cited
US4011167A
Cited
US4215682A
Cited
US4375718A
Cited
US4419993A
Cited
US4608173A
Cited
US4588537A
Cited
US4536440A
Cited
US4662005A
Cited
US4874659A
Cited
US4807619A
Cited
US4921645A
Cited
US4813948A
Cited
US4920960A
Cited
US4969457A
Cited
US5150703A
Cited
US4874399A
Cited
US4863785A
Cited
US5149468A
Cited
US5122048A
Cited
US5307796A
Cited
US5306534A
Cited
US5486411A
Cited
US5254297A
Cited
US5409766A
Cited
US5322061A
Cited
US5322061B1
Cited
US5436066A
Cited
US5482765A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-07-07 | 2001-01-06 | 2001-07-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-07-07 | 2005-01-06 | 2005-07-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-07-07 | 2009-01-06 | 2009-07-08 | $7700.00 | Window Closed / Lapsed |