US5139861A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for bonding blends of cellulosic pulp and fusible synthetic pulp or fiber by high-speed dielectric heating and products produced thereby
Assignee: EIDP Inc
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Filing: 1991-10-18
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Granted: 1992-08-18
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Expires: 2011-10-18
Abstract
Abstract A process is disclosed for bonding blends of cellulosic fluff pulp and fusible synthetic pulp or fiber having a melting point less than 250° C., by high-speed dielectric heating. The process works in the absence of any dielectric sensitizing material, but requires the resulting blend have a density between 0.005 and 0.50 g/cc so that the blend can be bonded in less than 15 seconds. The process is useful for producing disposable baby diapers, adult incontinence products and feminine pads.
Inventors
- 👤 Kenneth R. Williams
- 👤 Cornelius G. Fitzgerald
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 08:59
CPC Classifications
D; D04; D04H; D04H1/00; D04H1/40; D04H1/54; A; A61; A61L; A61L15/00; A61L15/16; A61L15/22; A61L15/225; Y; Y10; Y10S; Y10S428/00; Y10S428/913; Y10T; Y10T428/00; Y10T428/25; Y10T428/253; Y10T428/254; Y10T442/00; Y10T442/60; Y10T442/69
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
104 words
A process for bonding a blend of cellulosic fluff pulp and fusible synthetic pulp or fiber by dielectric heating, comprising the steps of: (a) intimately blending a dry cellulosic fluff pulp with a fusible synthetic pulp or fiber having a melting point less than 250 C, such that the resulting blend comprises between 5-98 parts cellulosic fluff pulp and between 2-95 parts fusible synthetic pulp or fiber and has a density between about 0.005 and about 0.50 g/cc; and (b) dielectrically heating the resulting blend in order to bond the blend in less than 15 seconds without the aid of any dielectric sensitizing material.
Claim 2
Dependent Claim
104 words
A process for bonding a blend of cellulosic fluff pulp and fusible synthetic pulp or fiber by dielectric heating, comprising the steps of: (a) intimately blending a dry cellulosic fluff pulp with a fusible synthetic pulp or fiber having a melting point less than 250 C, such that the resulting blend comprises between 5-98 parts cellulosic fluff pulp and between 2-95 parts fusible synthetic pulp or fiber and has a density between about 0.005 and about 0.50 g/cc; and (b) dielectrically heating the resulting blend in order to bond the blend in less than 15 seconds without the aid of any dielectric sensitizing material.
Claim 3
Dependent Claim
31 words
The process according to claim 1 further comprising the step of adding up to about 30 parts of a super absorbent polymer to the resulting blend before it is dielectrically heated.
Claim 4
Dependent Claim
30 words
The process according to claim 1 wherein the fusible synthetic pulp or fiber is selected from the group consisting of polyethylene, polypropylene, polyvinyl alcohol, polyester, 6 nylon and 6,6 nylon.
Claim 5
Dependent Claim
19 words
The process according to claim 1 wherein the cellulosic fluff pulp comprises wood pulp, cotton linters or cellulose fibers.
Claim 6
Dependent Claim
20 words
The process according to claim 1 wherein the resulting blend is dielectrically heated by applying RF energy or microwave energy.
Claim 7
Dependent Claim
23 words
The process according to claim 5 wherein between 70 and 2500 MHz of RF energy are applied to dielectrically heat the resulting blend.
Claim 8
Dependent Claim
71 words
A dielectrically bonded article having a density between about 0.005 and about 0.50 g/cc comprising: (a) 5-98 parts of a cellulosic fluff pulp; (b) 2-95 parts of a fusible synthetic pulp or fiber having a melting point less than 250 C; and wherein the tensile strength of the interior portion of the bonded article is at least 120% greater than the tensile strength of any surface portion of the bonded article.
Claim 9
Dependent Claim
71 words
A dielectrically bonded article having a density between about 0.005 and about 0.50 g/cc comprising: (a) 5-98 parts of a cellulosic fluff pulp; (b) 2-95 parts of a fusible synthetic pulp or fiber having a melting point less than 250 C; and wherein the tensile strength of the interior portion of the bonded article is at least 120% greater than the tensile strength of any surface portion of the bonded article.
Claim 10
Dependent Claim
20 words
The article according to claim 7 wherein the article further comprises up to 30 parts of a super absorbent polymer.
Claim 11
Dependent Claim
30 words
The article according to claim 7 wherein the fusible synthetic pulp or fiber is selected from the group consisting of polyethylene, polypropylene, polyvinyl alcohol, polyester, 6 nylon and 6,6 nylon.
Claim 12
Dependent Claim
19 words
The article according to claim 7 wherein the cellulosic fluff pulp comprises wood pulp, cotton linters or cellulose fibers.
Claim 13
Dependent Claim
25 words
The article according to claim 7 wherein the article comprises an absorptive core of a baby diaper, an adult incontinence product or a feminine pad.
Claim 14
Dependent Claim
18 words
The article according to claim 7 wherein the article comprises furniture padding, cushioning material or a polishing pad.
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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) | 1995-08-18 | 1996-02-17 | 1996-08-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-08-18 | 2000-02-17 | 2000-08-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-08-18 | 2004-02-17 | 2004-08-18 | $7700.00 | Window Closed / Lapsed |