US4233345A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thin-skin stabilization of pads of fluffed pulp
Assignee: Johnson and Johnson Professional Inc
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Filing: 1979-04-23
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Granted: 1980-11-11
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Expires: 1999-04-23
Abstract
Abstract A method is provided for the stabilization of a high loft, low density, air-laid pad of short length fibers by the formation of a thin, reinforcing layer on a surface thereof. The film is formed by first pretreating a surface of the pad with a light spray (at a level not higher than about 15 cc per sq. meter of the pad) of a solution of a coagulating material for a resin dispersion, and then applying the resin dispersion to the pretreated surface and limiting its penetration into the pad by instant coagulation thereof.
Inventors
- 👤 Robert T. Elias
- 👤 Dennis C. Holtman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 18:34
CPC Classifications
D; D21; D21H; D21H5/00; D21H5/26; D21H5/265; D21H5/2657; D21H5/2664; A; A61; A61F; A61F13/00; A61F13/15; A61F13/15203; A61L; A61L15/00; A61L15/16; A61L15/18; A61L15/22; A61L15/24; D04; D04H; D04H1/00; D04H1/40; D04H1/42; D04H1/425; D04H1/58; D04H1/64; D04H1/70; D04H1/72; D04H1/732; D21H23/00; D21H23/02; D21H23/22; D21H23/70; D21H25/00; D21H25/02; A61F13/53; A61F2013/530131
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
119 words
A method for stabilizing a high loft, low density air laid pad of short length fibers which comprises pretreating a surface of said pad with a light spray, at a level not higher than about 15 cc per sq. meter and not higher than about 5% of the weight per unit area of said pad of a solution of a coagulating material for a resin dispersion while maintaining substantially the entire interior of said pad dry, applying said resin dispersion to said pretreated surface thereby causing coagulation of said dispersion and limiting its penetration to the interior of said pad whereby a reinforcing layer is obtained on said pad while maintaining substantially its original high loft and absorptive capacity.
Claim 2
Independent Claim
119 words
A method for stabilizing a high loft, low density air laid pad of short length fibers which comprises pretreating a surface of said pad with a light spray, at a level not higher than about 15 cc per sq. meter and not higher than about 5% of the weight per unit area of said pad of a solution of a coagulating material for a resin dispersion while maintaining substantially the entire interior of said pad dry, applying said resin dispersion to said pretreated surface thereby causing coagulation of said dispersion and limiting its penetration to the interior of said pad whereby a reinforcing layer is obtained on said pad while maintaining substantially its original high loft and absorptive capacity.
Claim 3
Dependent Claim
38 words
The method of claim 1 wherein said light spray is at a level between about 2 and about 10 cc per sq. meter and not higher than about 3% of the weight per unit area of said pad.
Claim 4
Dependent Claim
14 words
The method of claim 1 wherein said pad is composed substantially of cellulosic fibers.
Claim 5
Dependent Claim
15 words
The method of claim 3 wherein said pad is composed substantially of wood pulp fibers.
Claim 6
Dependent Claim
18 words
The method of claim 1 wherein said pad has a density from about 0.05 to about 0.20 g/cc.
Claim 7
Dependent Claim
17 words
The method of claim 1 wherein said pad is dried after application of said resin binder dispersion.
Claim 8
Dependent Claim
31 words
The method of claim 1 wherein said resin dispersion comprises a dispersion of a cross-linked acrylic acid polymer and said coagulating material comprises an aqueous solution of an alkali metal hydroxide.
Claim 9
Dependent Claim
72 words
The method of claim 7 wherein said acrylic acid polymer has an equivalent weight of 76 per free acid hydrogen ion and an average molecular weight of about 4,000,000 wherein said dispersion is applied to said pad at a rate of about 45 cc per sq. meter, wherein said coagulating material is applied at a rate of about 5 cc per sq. meter and comprises a 5 wt.% solution of sodium hydroxide.
Claim 10
Independent Claim
158 words
A method for stabilizing a high loft, low density air laid pad, composed substantially of short length wood pulp fibers and having a density from about 0.05 to about 0.20 g/cc, which comprises pretreating a surface of said pad with a light spray, at a level from about 2 to about 10 cc sq. meter and not higher than about 3% of the weight per unit area of said pad of a solution of sodium hydroxide while maintaining substantially the entire interior of said pad dry, applying to said pretreated surface an aqueous dispersion of a cross-linked acrylic acid polymer having an equivalent weight of 76 per free acid hydrogen and an average molecular weight of about 4,000,000 thereby causing coagulation of said dispersion and limiting its penetration to the interior of said pad, and thereafter drying said pad whereby a reinforcing layer is obtained on said pad while maintaining substantially its original high loft and absorptive capacity.
Claim 11
Independent Claim
158 words
A method for stabilizing a high loft, low density air laid pad, composed substantially of short length wood pulp fibers and having a density from about 0.05 to about 0.20 g/cc, which comprises pretreating a surface of said pad with a light spray, at a level from about 2 to about 10 cc sq. meter and not higher than about 3% of the weight per unit area of said pad of a solution of sodium hydroxide while maintaining substantially the entire interior of said pad dry, applying to said pretreated surface an aqueous dispersion of a cross-linked acrylic acid polymer having an equivalent weight of 76 per free acid hydrogen and an average molecular weight of about 4,000,000 thereby causing coagulation of said dispersion and limiting its penetration to the interior of said pad, and thereafter drying said pad whereby a reinforcing layer is obtained on said pad while maintaining substantially its original high loft and absorptive capacity.
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) | 1983-11-11 | 1984-05-12 | 1984-11-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-11-11 | 1988-05-12 | 1988-11-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-11-11 | 1992-05-12 | 1992-11-11 | $7700.00 | Window Closed / Lapsed |