US4333464A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sanitary napkin
Assignee: Zenmi Co Ltd
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Filing: 1980-04-11
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Granted: 1982-06-08
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Expires: 2000-04-11
Abstract
Abstract Sanitary napkin comprising at least a layer consisting of a water-absorbing substance containing a powdery polymer which is soluble in water or is dispersible in water and is highly water-absorbable and at least a film based on polyvinyl alcohol, which is soluble in water or is dispersible in water is disclosed, the napkin being excellent in absorbing and holding the menstrural blood, in preventing the exudation and the leakage of the menstrural blood once absorbed therein and in disintegrating in water.
Inventors
- 👤 Tadao Nakano
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 11:22
CPC Classifications
A; A61; A61F; A61F13/00; A61F13/15; A61F13/53; A61F13/534; A61F13/15203; A61F13/15211; A61L; A61L15/00; A61L15/16; A61L15/18; A61L15/22; A61L15/24; A61F2013/530131; A61F2013/530481; A61F2013/53445; A61F13/84; A61F2013/8488; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2982; Y10T428/2991; Y10T428/2998; Y10T428/31504; Y10T428/31855; Y10T428/31909; Y10T428/31913; Y10T428/31924; Y10T428/31928; Y10T428/31971; Y10T428/31975
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
69 words
A sanitary napkin comprising at least one layer formulated of a water-absorbable substance and at least one layer consisting of a film based on water-soluble or water-dispersible polyvinyl alcohol, said water-absorbable substance comprising a powder of a water-soluble of water-dispersible polymeric substance and a powder of a gelatinizing accelerator for polyvinyl alcohol selected from the group consisting of boric acid, sodium borate, sodium surface, magnesium sulfate and aluminum sulfate.
Claim 2
Dependent Claim
69 words
A sanitary napkin comprising at least one layer formulated of a water-absorbable substance and at least one layer consisting of a film based on water-soluble or water-dispersible polyvinyl alcohol, said water-absorbable substance comprising a powder of a water-soluble of water-dispersible polymeric substance and a powder of a gelatinizing accelerator for polyvinyl alcohol selected from the group consisting of boric acid, sodium borate, sodium surface, magnesium sulfate and aluminum sulfate.
Claim 3
Dependent Claim
27 words
The sanitary napkin of claim 1, wherein said layer of water-absorbable substance and said layer of a film based on polyvinyl alcohol are adjacent to one another.
Claim 4
Dependent Claim
69 words
The sanitary napkin of claim 1, wherein said polymeric substance is one or more species selected from the group consisting of starch, processed starch, cross-linked starch, starch grafted with acrylic monomer, carboxymethyl cellulose and its cross-linked products, hydrophilic copolymers of acrylic monomers, polyethylene oxide and its cross-linked products, copolymers of vinyl ester and ethylenically unsaturated carboxylic acids and their saponification products, polyvinyl alcohol and its derivatives, and cellulose derivatives.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-06-07 | 1985-12-07 | 1986-06-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-06-07 | 1989-12-07 | 1990-06-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-06-07 | 1993-12-07 | 1994-06-08 | $7700.00 | Window Closed / Lapsed |