← Back to Patent Explorer
US4600458A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of making an absorbent laminate structure

Assignee: Procter and Gamble Co
•
Filing: 1985-07-02
•
Granted: 1986-07-15
•
Expires: 2005-07-02
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract The present invention provides a layered absorbent structure, the structure having an upper surface and a lower surface. The structure comprises: (a) n webs of fibrous material, n being an integer of two or more. The webs are layered such that there is an uppermost web, a lowermost web, n-2 intermediate webs, and n-1 interfaces of two opposed adjacent contacting surfaces of adjacent webs. Each of the interfaces has a surface area. (b) Absorbent particles forming a discontinuous layer at one or more of the interfaces. The opposed adjacent contacting surfaces at each interface where particles are present are substantially entirely frangibly bonded by fiber entanglement between the contacting surfaces. The particles are immobilized at said interface(s) substantially entirely by fiber entrapment.

Inventors

  • 👤 Timothy A. Kramer
  • 👤 Gerald A. Young
  • 👤 Ronald W. Kock

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 12:20
CPC Classifications
A; A61; A61F; A61F13/00; A61F13/15; A61F13/53; A61F13/534; A61F13/535; A61F13/536; A61F13/15577; A61F2013/15821; A61F13/51; A61F2013/51078; A61F2013/530437; A61F2013/530481; A61F2013/530489; A61F2013/530496; A61F2013/53051; A61F2013/53445; Y; Y10; Y10T; Y10T156/00; Y10T156/10; Y10T156/1002; Y10T156/1007; Y10T156/17; Y10T156/1702; Y10T156/1712; Y10T156/1737

Claims Analysis

Total Claims: 24
Claim 1
Independent Claim 143 words
A process for making a layered absorbent structure, said absorbent structure comprising the following components: (1) n substantially planar webs of fibrous materials, each of said webs having two substantially parallel surfaces, n being an integer of two or more; and (2) absorbent particles; said process comprising the following steps: (a) layering said webs in substantially planar contact such that there is an uppermost web, a lowermost web, n-2 intermediate webs, and n-1 interfaces of two opposed adjacent contacting surfaces of adjacent webs, each of said interfaces having a surface area, whereby a layered stack of webs is formed; (b) spreading said particles such that said particles form a discontinuous layer at one or more of said interfaces; and (c) crimping said layered stack of webs with said particles at said interface(s) between two crimping surfaces having mating z-direction geometrical protrusions and concavities.
Claim 2
Dependent Claim 143 words
A process for making a layered absorbent structure, said absorbent structure comprising the following components: (1) n substantially planar webs of fibrous materials, each of said webs having two substantially parallel surfaces, n being an integer of two or more; and (2) absorbent particles; said process comprising the following steps: (a) layering said webs in substantially planar contact such that there is an uppermost web, a lowermost web, n-2 intermediate webs, and n-1 interfaces of two opposed adjacent contacting surfaces of adjacent webs, each of said interfaces having a surface area, whereby a layered stack of webs is formed; (b) spreading said particles such that said particles form a discontinuous layer at one or more of said interfaces; and (c) crimping said layered stack of webs with said particles at said interface(s) between two crimping surfaces having mating z-direction geometrical protrusions and concavities.
Claim 3
Dependent Claim 13 words
The process of claim 1 wherein said absorbent particles are superabsorbent polymer particles.
Claim 4
Dependent Claim 25 words
The process of claim 2 wherein one or both of said crimping surfaces have from about 10 to about 50 discrete protrusions per square centimeter.
Claim 5
Dependent Claim 39 words
The process of claim 3 wherein said protrusions have a base, a tip, and a z-direction height which is the distance from said base to said tip, said z-direction height being from about 1 mm to about 5 mm.
Claim 6
Dependent Claim 18 words
The process of claim 4 wherein said protrusions are tapered substantially entirely from said base to said tip.
Claim 7
Dependent Claim 15 words
The process of claim 5 wherein said protrusions are pyramidal-shaped and are all substantially identical.
Claim 8
Dependent Claim 15 words
The process of claim 5 wherein said protrusions are conical-shaped and are all substantially identical.
Claim 9
Dependent Claim 22 words
The process of claim 2 wherein said crimping surfaces are rigid and are the cylindrical surfaces of a pair of crimping rolls.
Claim 10
Dependent Claim 22 words
The process of claim 5 wherein said crimping surfaces are rigid and are the cylindrical surfaces of a pair of crimping rolls.
Claim 11
Dependent Claim 56 words
The process of claim 2 wherein all of said components are maintained substantially dry throughout said process; said opposed adjacent contacting surfaces at each said interface where said particles are present are substantially entirely frangibly bonded by fiber entanglement between said contacting surfaces; and said particles are immobilized at said interface(s) substantially entirely by fiber entrapment.
Claim 12
Dependent Claim 56 words
The process of claim 5 wherein all of said components are maintained substantially dry throughout said process; said opposed adjacent contacting surfaces at each said interface where said particles are present are substantially entirely frangibly bonded by fiber entanglement between said contacting surfaces; and said particles are immobilized at said interface(s) substantially entirely by fiber entrapment.
Claim 13
Dependent Claim 29 words
The process of claim 2 wherein said particles are spread such that said particles form a substantially uniformly distributed layer at each said interface where said particles are present.
Claim 14
Dependent Claim 45 words
The process of claim 11 wherein said particles are spread such that said particles form a substantially uniformly distributed layer at each said interface where particles are present, and such that said particles cover less than 50% of said surface area at each said interface.
Claim 15
Dependent Claim 26 words
The process of claim 13 wherein about 90% (by weight) or more of said particles are from about 0.05 mm to about 1.0 mm in diameter.
Claim 16
Dependent Claim 30 words
The process of claim 14 wherein said webs are webs of absorbent tissues each having a basis weight of from about 15 g/m 2 to about 40 g/m 2 .
Claim 17
Dependent Claim 29 words
The process of claim 3 wherein said process comprises the following additional step after step (c): (d) compressing said layered stack of webs between two substantially smooth compressing surfaces.
Claim 18
Dependent Claim 47 words
The process of claim 16 wherein said smooth compressing surfaces are rigid and are the cylindrical surfaces of a pair of compression rolls and the pressure at the nip of the rolls is from about 5 kg/cm of web width to about 50 kg/cm of web width.
Claim 19
Dependent Claim 179 words
A process for making a layered absorbent structure, said absorbent comprising the following components: (1) n substantially planar webs of fibrous materials, each of said webs having two substantially parallel surfaces, n being an integer of two or more; and (2) absorbent particles; said process comprising the following steps: (a) layering said webs in substantially planar contact such that there is an uppermost web, a lowermost web, n-2 intermediate webs, and n-1 interfaces of two opposed adjacent contacting surfaces of adjacent webs, each of said interfaces having a surface area, whereby a layered stack of webs is formed; (b) spreading said particles such that said particles form a discontinuous layer at one or more of said interfaces; and (c) imparting a shearing action between said opposed adjacent contacting surfaces at each said interface where said particles are present, whereby said opposed adjacent contacting surfaces at each said interface were said particles are present are substantially entirely fangibly bonded by fiber entanglement between said contacting surfaces, and whereby said particles are immobilized at said interface(s) substantially entirely by fiber entrapment.
Claim 20
Dependent Claim 179 words
A process for making a layered absorbent structure, said absorbent comprising the following components: (1) n substantially planar webs of fibrous materials, each of said webs having two substantially parallel surfaces, n being an integer of two or more; and (2) absorbent particles; said process comprising the following steps: (a) layering said webs in substantially planar contact such that there is an uppermost web, a lowermost web, n-2 intermediate webs, and n-1 interfaces of two opposed adjacent contacting surfaces of adjacent webs, each of said interfaces having a surface area, whereby a layered stack of webs is formed; (b) spreading said particles such that said particles form a discontinuous layer at one or more of said interfaces; and (c) imparting a shearing action between said opposed adjacent contacting surfaces at each said interface where said particles are present, whereby said opposed adjacent contacting surfaces at each said interface were said particles are present are substantially entirely fangibly bonded by fiber entanglement between said contacting surfaces, and whereby said particles are immobilized at said interface(s) substantially entirely by fiber entrapment.
Claim 21
Dependent Claim 32 words
The process of claim 18 wherein said shearing action is imparted by compressing said layered stack in the nip of smooth compression rolls where there is a differential speed between said rolls.
Claim 22
Dependent Claim 13 words
The process of claim 18 wherein said absorbent particles are superabsorbent polymer particles.
Claim 23
Dependent Claim 17 words
The process of claim 20 wherein all of said components are maintained substantially dry throughout said process.
Claim 24
Dependent Claim 29 words
The process of claim 20 wherein said particles are spread such that said particles form a substantially uniformly distributed layer at each said interface where said particles are present.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1989-07-14 1990-01-13 1990-07-15 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1993-07-14 1994-01-13 1994-07-15 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1997-07-14 1998-01-13 1998-07-15 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag