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US4417893A Expired / Lapsed US ⏱️ 0.0 years remaining

Sanitary napkin

Assignee: Kao Corp
•
Filing: 1978-06-08
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Granted: 1983-11-29
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Expires: 1998-06-08
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Abstract

Abstract A sanitary napkin comprising an absorbent, a liquid-impervious layer covering the bottom, sides and top edge of the absorbent and a non-woven wrapper fabric covering the absorbent and the liquid-impervious layer, wherein the non-woven fabric has a double layer structure comprising a web layer in which most of the fibers are oriented uniformly and another web layer in which the fibers are randomly arranged.

Inventors

  • 👤 Hiroshi Mizutani
  • 👤 Yoshimi Tsuchiya

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 14:42
CPC Classifications
B; B32; B32B; B32B5/00; B32B5/22; B32B5/24; B32B5/26; A; A61; A61F; A61F13/00; A61F13/15; A61F13/53; A61F13/538; B32B5/02; B32B5/022; A61F13/51; A61F2013/51002; A61F2013/51038; A61F2013/51042; B32B2555/00; B32B2555/02

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 206 words
In a sanitary napkin for menstrual discharges, comprising an absorbent core, a liquid-impervious layer covering the bottom, sides and the edge portion of the top surface of the absorbent core and a non-woven fabric covering the remainder of the top surface of the absorbent core, the improvement which comprises: said non-woven fabric consists essentially of a unitary laminate of an inner layer disposed adjacent to said absorbent core and an outer layer disposed on the opposite side of said inner layer from said absorbent core, each of said inner and outer layers consisting essentially of a blend of hydrophilic fibers and heat-fusible hydrophobic fibers with said inner layer containing a higher proportion of hydrophilic fibers than said outer layer, one of said inner and outer layers consisting essentially of randomly oriented fibers in a fluffy bulky state, the other of said inner and outer layers consisting essentially of substantially uniformly oriented fibers and having a high longitudinal tensile strength, the hydrophobic fibers of said first and second layers being heat-fused to each other at the locations where they are in contact with each other to unite said first and second layers to each other and to maintain the structural integrity of said first and second layers.
Claim 2
Dependent Claim 206 words
In a sanitary napkin for menstrual discharges, comprising an absorbent core, a liquid-impervious layer covering the bottom, sides and the edge portion of the top surface of the absorbent core and a non-woven fabric covering the remainder of the top surface of the absorbent core, the improvement which comprises: said non-woven fabric consists essentially of a unitary laminate of an inner layer disposed adjacent to said absorbent core and an outer layer disposed on the opposite side of said inner layer from said absorbent core, each of said inner and outer layers consisting essentially of a blend of hydrophilic fibers and heat-fusible hydrophobic fibers with said inner layer containing a higher proportion of hydrophilic fibers than said outer layer, one of said inner and outer layers consisting essentially of randomly oriented fibers in a fluffy bulky state, the other of said inner and outer layers consisting essentially of substantially uniformly oriented fibers and having a high longitudinal tensile strength, the hydrophobic fibers of said first and second layers being heat-fused to each other at the locations where they are in contact with each other to unite said first and second layers to each other and to maintain the structural integrity of said first and second layers.
Claim 3
Dependent Claim 23 words
A sanitary napkin according to claim 1, wherein the outer layer of the non-woven fabric is said one layer of randomly oriented fibers.
Claim 4
Dependent Claim 23 words
A sanitary napkin according to claim 1, wherein the outer layer of the non-woven fabric is said other layer of uniformly oriented fibers.
Claim 5
Dependent Claim 74 words
A sanitary napkin as claimed in claim 2, in which the weight ratio of hydrophilic fibers to hydrophobic fibers in said outer layer is from 90/10 to 40/60, the weight ratio of hydrophilic fibers to hydrophobic fibers in said inner layer is from 95/5 to 50/50 and is higher than the corresponding ratio in the outer layer, and the weight ratio of the outer layer to the inner layer is from 80/20 to 20/80.
Claim 6
Dependent Claim 62 words
A sanitary napkin as claimed in claim 4, in which the weight ratio of hydrophilic fibers to hydrophobic fibers in said outer layer is from 80/20 to 50/50, the weight ratio of hydrophilic fibers to hydrophobic fibers in said inner layer is from 90/10 to 60/40, and the weight ratio of said outer layer to said inner layer is 80/20 to 50/50.
Claim 7
Dependent Claim 67 words
A sanitary napkin as claimed in claim 3, in which the weight ratio of hydrophilic fibers to hydrophobic fibers in said outer layer is from 90/10 to 40/60, the weight ratio of hydrophilic fibers to hydrophobic fibers in said inner layer is from 100/0 to 50/50 and the weight ratio of the outer uniform web layer to the inner random web layer is from 80/20 to 20/80.
Claim 8
Dependent Claim 47 words
A sanitary napkin as claimed in claim 6, in which the weight ratio of hydrophilic fibers to hydrophobic fibers in said outer layer is from 80/20 to 50/50 and the weight ratio of hydrophilic fibers to hydrophobic fibers in said inner layer is from 90/10 to 60/40.

References Cited (Backward Citations)

US2862251A Cited
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US3294091A Cited
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US3768118A Cited
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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1986-11-28 1987-05-30 1987-11-29 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1990-11-28 1991-05-30 1991-11-29 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1994-11-28 1995-05-30 1995-11-29 $7700.00 Window Closed / Lapsed

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