US5143773A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Highly hygroscopic laminate
Assignee: Resonac Holdings Corp
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Filing: 1991-03-28
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Granted: 1992-09-01
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Expires: 2011-03-28
Abstract
Abstract A hygroscopic laminate comprises a hygroscopic layer comprising a gas permeable film, and a water-absorbing polymer and at least one humectant selected from the group consisting of acetic acid, propionic acid, glycolic acid, lactic acid, hydracrylic acid, pyruvic acid and pyrrolidonecarboxylic acid and sodium, potassium, calcium and magnesium salts of these acids, which are wrapped in the gas permeable film; a porous non-water retention sheet; and a water impermeable sheet, the porous non-water retention sheet being disposed on one side of the hygroscopic layer and the water impermeable sheet being disposed on the other side of the hygroscopic layer, to thereby sandwich the hygroscopic layer. The hygroscopic laminate controls the relative humidity in a packaged system to 20 to 40%.
Inventors
- 👤 Masami Takuno
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 21:40
CPC Classifications
B; B32; B32B; B32B7/00; B32B7/02; B32B33/00; B32B3/00; B32B3/26; B32B3/266; B32B5/00; B32B5/18; B65; B65D; B65D81/00; B65D81/24; B65D81/26; B65D81/266; B65D81/267; B32B2305/00; B32B2305/02; B32B2305/026; B32B2307/00; B32B2307/70; B32B2307/724; B32B2307/726; B32B2307/7265; B32B2307/728; B32B2553/00; Y; Y02; Y02W; Y02W90/00; Y02W90/10; Y10; Y10T; Y10T428/00; Y10T428/24; Y10T428/24273; Y10T428/24322; Y10T428/24331; Y10T428/24777; Y10T428/24793; Y10T428/24802; Y10T428/24826; Y10T428/249921; Y10T428/249953; Y10T428/249981; Y10T428/249986; Y10T442/00; Y10T442/60; Y10T442/674; Y10T442/678
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
106 words
A hygroscopic laminate comprising a hygroscopic layer which comprises a gas permeable film, and a water-absorbing polymer and at least one humectant selected from the group consisting of acetic acid, propionic acid, glycolic acid, lactic acid, hydracrylic acid, pyruvic acid and pyrrolidonecarboxylic acid and sodium, potassium, calcium and magnesium salts of these acids, which are wrapped in the gas permeable film; a porous non-water retention sheet; and a water impermeable sheet, the porous non-water retention sheet being disposed on one side of the hygroscopic layer and the water impermeable sheet being disposed on the other side of the hygroscopic layer, to thereby sandwich the hygroscopic layer.
Claim 2
Dependent Claim
106 words
A hygroscopic laminate comprising a hygroscopic layer which comprises a gas permeable film, and a water-absorbing polymer and at least one humectant selected from the group consisting of acetic acid, propionic acid, glycolic acid, lactic acid, hydracrylic acid, pyruvic acid and pyrrolidonecarboxylic acid and sodium, potassium, calcium and magnesium salts of these acids, which are wrapped in the gas permeable film; a porous non-water retention sheet; and a water impermeable sheet, the porous non-water retention sheet being disposed on one side of the hygroscopic layer and the water impermeable sheet being disposed on the other side of the hygroscopic layer, to thereby sandwich the hygroscopic layer.
Claim 3
Dependent Claim
28 words
A hygroscopic laminate as set forth in claim 1, wherein the water-absorbing polymer is selected from those obtained by three-dimensionally polymerizing a hydrophilic polymer with a crosslinking agent.
Claim 4
Dependent Claim
54 words
A hygroscopic laminate as set forth in claim 2, wherein the hydrophilic polymer is selected from those obtained by graft-polymerizing a water-soluble polymerizable monomer or a polymerizable monomer which is made water-soluble through hydrolysis with a polysaccharide, and optionally hydrolyzing the resulting graft polymer, and polyethylene oxide, sulfonated polyethylene, polyacrylic acid and polymethacrylic acid.
Claim 5
Dependent Claim
28 words
A hygroscopic laminate as set forth in claim 1, wherein an additive selected from hygroscopic amino acids and salts thereof and inorganic salts is added to the humectant.
Claim 6
Dependent Claim
20 words
A hygroscopic laminate as set forth in claim 1, wherein the humectant is selected from sodium lactate and sodium pyrrolidonecarboxylate.
Claim 7
Dependent Claim
31 words
A hygroscopic laminate as set forth in claim 1, wherein the porous non-water retention sheet is selected from uniformly perforated polyethylene, polypropylene and polyester films and non-woven polyester and polyolefin fabrics.
Claim 8
Dependent Claim
35 words
A hygroscopic laminate as set forth in claim 1, wherein the gas permeable film is selected from paper, non-woven fabrics, felt and coarse net structures of cellulose fibers or a mixture thereof with another fiber.
Claim 9
Dependent Claim
23 words
A hygroscopic laminate as set forth in claim 1, which is sealed at the periphery to prevent water leakage through the side portions.
Claim 10
Dependent Claim
24 words
A hygroscopic laminate as set forth in claim 1, wherein the gas permeable film and/or the hygroscopic layer comprise an antibacterial or mildew-proofing agent.
Claim 11
Dependent Claim
22 words
A hygroscopic laminate as set forth in claim 1, which controls the relative humidity in a packaged system to 20 to 40%.
References Cited (Backward Citations)
US4645698A
Cited
US4823783A
Cited
US4888231A
Cited
US4902565A
Cited
US4822669A
Cited
US4824718A
Cited
US5055332A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-09-01 | 1996-03-02 | 1996-09-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-09-01 | 2000-03-02 | 2000-09-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-09-01 | 2004-03-02 | 2004-09-01 | $7700.00 | Window Closed / Lapsed |