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US4612231A Expired / Lapsed US ⏱️ 0.0 years remaining

Patterned dry laid fibrous web products of enhanced absorbency

Assignee: Fort James Corp
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Filing: 1984-09-24
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Granted: 1986-09-16
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Expires: 2004-09-24
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Abstract

Abstract A method of improving absorbency of air laid bonded fibrous webs and the products resulting therefrom, the preferred method comprising the step of imprinting at least one surface of the fibrous web between a pair of cylindrical rolls under a pressure of at least 100 pounds/lineal inch, the compacted area of each imprinted web surface being at least 40%, preferably at least 50%, of the total imprinted surface. In the preferred embodiment of the method, the fibrous web is first wetted with water, the imprinting step then being conducted with imprinting means heated to about 140° to about 180° C. The products obtained have densified zones underlying the compacted areas, the density thereof being at least 0.1 gm./cc., which zones enhance absorbency as compared to unimprinted webs by at least 25%. The preferred webs provided by the method are imprinted with a grid-like pattern, said pattern preventing nesting of individual sheets in product rolls and containers.

Inventors

  • 👤 Michael P. Bouchette
  • 👤 Johannes A. Van den Akker
  • 👤 William R. Watt

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-06 04:11
CPC Classifications
D; D21; D21H; D21H5/00; D21H5/26; D21H5/265; D21H5/2657; D21H5/2671; A; A47; A47L; A47L13/00; A47L13/10; A47L13/16; D21H25/00; D21H25/04; D21H27/00; D21H27/02; Y; Y10; Y10T; Y10T156/00; Y10T156/10; Y10T156/1002; Y10T156/1007; Y10T156/1023; Y10T156/1039; Y10T428/00; Y10T428/24; Y10T428/24479; Y10T428/2457; Y10T428/24595; Y10T428/24603

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 145 words
A dry laid fibrous web product of high bulk and enhanced absorbency rate comprising: (a) a dry laid web of randomly distributed wood pulp fibers; (b) an adhesive material substantially permeating said web, adjacent fibers being bonded to one another thereby, and (c) an imprinted pattern on at least one surface of said web, the pattern subdividing said surface into compacted regions and non-compacted regions in alternating relationship to one another, the area of the compacted regions being between about 50% and about 80% of each imprinted surface, the compacted regions having a density in the range of about 0.2 g/cc to about 0.5 g/cc; whereby the portions of the web product underlying the compacted regions are compressed and densified reducing thereby the interstitial voids between adjacent fibers within said densified portions so that wiping absorbency is enhanced by increasing capillary tension and promoting wicking.
Claim 2
Dependent Claim 145 words
A dry laid fibrous web product of high bulk and enhanced absorbency rate comprising: (a) a dry laid web of randomly distributed wood pulp fibers; (b) an adhesive material substantially permeating said web, adjacent fibers being bonded to one another thereby, and (c) an imprinted pattern on at least one surface of said web, the pattern subdividing said surface into compacted regions and non-compacted regions in alternating relationship to one another, the area of the compacted regions being between about 50% and about 80% of each imprinted surface, the compacted regions having a density in the range of about 0.2 g/cc to about 0.5 g/cc; whereby the portions of the web product underlying the compacted regions are compressed and densified reducing thereby the interstitial voids between adjacent fibers within said densified portions so that wiping absorbency is enhanced by increasing capillary tension and promoting wicking.
Claim 3
Dependent Claim 18 words
The product of claim 1 wherein the compacted regions represent between 50 and 70% of each imprinted surface.
Claim 4
Dependent Claim 27 words
The product of claimm 1 wherein the pattern is in the form of a grid comprising a plurality of discontinuous compacted region and contiguous non-compacted bridge regions.
Claim 5
Dependent Claim 33 words
The product of claim 3 wherein each compacted region has an area between about 0.05 to about 0.562 sq. in. and the bridge regions have a width between about 0.05 to 0.10 inch.
Claim 6
Dependent Claim 28 words
The products of claim 3 wherein absorbency rate as measured by mirror wipe time (MWT) is reduced by at least 25% as compared to corresponding unimprinted web products.
Claim 7
Dependent Claim 27 words
The product of claim 3 wherein the pattern is in the form of a grid comprising a plurality of discontinuous non-compacted regions and contiguous compacted channel regions.
Claim 8
Dependent Claim 36 words
The product of claim 6 wherein the non-compacted regions each has an area of between about 0.08 to about 0.25 square inch and the channel regions have a width of between about 0.15 to 0.36 inch.
Claim 9
Dependent Claim 29 words
The products of claim 1 wherein the absorbency rate as measured by mirror wipe time (MWT) is reduced by at least 40% as compared to corresponding unimprinted web products.
Claim 10
Dependent Claim 22 words
The products of claim 1 wherein the absorbency rate as measured by mirror wipe time (MWT) is less than about 15 seconds.
Claim 11
Dependent Claim 13 words
The products of claim 1, wherein each surface of the web is imprinted.
Claim 12
Dependent Claim 169 words
A dry laid fibrous web product of high bulk and an enhanced absorbency rate prepared by the process comprising the steps of: (a) randomly distributing dry fibers onto a moving forminous support means to provide a dry loose web; (b) consolidating the dry loose web; (c) bonding the consolidated web with an adhesive material, the adhesive material substantially permeating the consolidated web; (d) curing the adhesive material prior to take-up of the cured web on a parent roll; and (e) enhancing the rate of absorbency by the step of imprinting by application of pressure on at least one surface of the web, each imprinted web surface having a pattern characterized by a compacted area of from 50% to 80% of the total imprinted surface area, the imprinting being performed at any step in the method subsequent to the consolidation of the dry loose web, wherein the imprinting is performed under a pressure sufficient to compact and densify the web to a density of about 0.2 g/cc to about 0.5/cc.
Claim 13
Dependent Claim 169 words
A dry laid fibrous web product of high bulk and an enhanced absorbency rate prepared by the process comprising the steps of: (a) randomly distributing dry fibers onto a moving forminous support means to provide a dry loose web; (b) consolidating the dry loose web; (c) bonding the consolidated web with an adhesive material, the adhesive material substantially permeating the consolidated web; (d) curing the adhesive material prior to take-up of the cured web on a parent roll; and (e) enhancing the rate of absorbency by the step of imprinting by application of pressure on at least one surface of the web, each imprinted web surface having a pattern characterized by a compacted area of from 50% to 80% of the total imprinted surface area, the imprinting being performed at any step in the method subsequent to the consolidation of the dry loose web, wherein the imprinting is performed under a pressure sufficient to compact and densify the web to a density of about 0.2 g/cc to about 0.5/cc.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1989-09-15 1990-03-17 1990-09-16 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1993-09-15 1994-03-17 1994-09-16 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1997-09-15 1998-03-17 1998-09-16 $7700.00 Window Closed / Lapsed

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