US4898642A — Twisted, chemically stiffened cellulosic fibers a…

Claim 1

Independent Claim 157 words

Cellosic fibrous material comprising individualized, chemically stiffened, curled cellulosic fibers and a crosslinking agent, wherein said crosslinking agent is selected from the group consisting of C 2 -C 8 dialdehydes, C 2 -C 8 dialdehyde acid analoques having at least one aldehyde group, and oligomers of said dialdehydes and dialdehyde acid analogues, said fibers chemically stiffened by reaction with from about 0.75 mole % to about 2.0 mole % of said crosslinking agent, calculated on a cellulose anhydroglucose molar basis, said fibers having: a. an average dry fiber twist count of at least about 4.5 twist nodes per millimeter; b. an average wet fiber twist count of at least about 3.0 twist nodes per millimeter and at least about 0.5 twist nodes per millimeter less than said dry fiber twist count; c. an average isopropyl alcohol retention value of less than about 30%; and d. an average water retention value of between about 28% and about 50%.

Claim 2

Dependent Claim 157 words

Cellosic fibrous material comprising individualized, chemically stiffened, curled cellulosic fibers and a crosslinking agent, wherein said crosslinking agent is selected from the group consisting of C 2 -C 8 dialdehydes, C 2 -C 8 dialdehyde acid analoques having at least one aldehyde group, and oligomers of said dialdehydes and dialdehyde acid analogues, said fibers chemically stiffened by reaction with from about 0.75 mole % to about 2.0 mole % of said crosslinking agent, calculated on a cellulose anhydroglucose molar basis, said fibers having: a. an average dry fiber twist count of at least about 4.5 twist nodes per millimeter; b. an average wet fiber twist count of at least about 3.0 twist nodes per millimeter and at least about 0.5 twist nodes per millimeter less than said dry fiber twist count; c. an average isopropyl alcohol retention value of less than about 30%; and d. an average water retention value of between about 28% and about 50%.

Claim 3

Dependent Claim 22 words

Cellulosic fibrous material as in claim 1, wherein said fibers have an average dry fiber curl factor of at least about 0.30.

Claim 4

Dependent Claim 19 words

Cellulosic fibrous material as in claim 2, wherein said average dry fiber curl factor is at least about 0.50.

Claim 5

Dependent Claim 56 words

Cellulosic fibrous material as in claim 1, wherein said average dry fiber twist count is at least about 5.5 twist nodes per millimeter and said average wet fiber twist count is at least about 4 twist nodes per millimeter and at least about 1.0 twist node per millimeter less than said average dry fiber twist count.

Claim 6

Dependent Claim 39 words

Cellulosic fibrous material as in claim 4, wherein said average dry fiber twist count is at least about 6.5 twist nodes per millimeter and said average wet fiber twist count is at least about 5.0 twist nodes per millimeter.

Claim 7

Dependent Claim 19 words

Cellulosic fibrous material as in claim 1, wherein said average isopropyl alcohol retention value is less than about 27%.

Claim 8

Dependent Claim 20 words

Cellulosic fibrous material as in claim 6, wherein said average water retention value is between about 30% and about 45%.

Claim 9

Dependent Claim 23 words

Cellulosic fibrous material as in claim 7, wherein said fibers have an average water retention value of between about 35% and about 42%.

Claim 10

Dependent Claim 65 words

Cellulosic fibrous material as in claim 8, wherein said average dry fiber curl factor is at least about 0.50, said average dry twist count is at least about 6.5 twist nodes per millimeter, and said average wet twist count is at least about 5.0 twist nodes per millimeter and is at least about 1.0 twist node per millimeter less than said average wet twist count.

Claim 11

Dependent Claim 29 words

The cellulosic fibrous material of claim 9, wherein said crosslinking agent is selected from the group consisting of glutaraldehyde, glyoxal, and glyoxylic acid, said fibers being individually stiffened therewith.

Claim 12

Dependent Claim 13 words

Cellulosic fibrous material as in claim 10, wherein said crosslinking agent is glutaraldehyde.

Claim 13

Dependent Claim 159 words

An absorbent structure comprising a mass of individualized, chemically stiffened, curled cellulosic fibers and a crosslinking agent, wherein said crosslinking agent is selected from the group consisting of C 2 -C 8 dialdehydes, C 2 -C 8 dialdehyde acid analogues having at least one aldehyde group, and oligmers of said dialdehydes and dialdehyde acid analogues, said fibers chemically stiffened by reaction with from about 0.75 mole % to about 2.0 mole % of said crosslinking agent, calculated on a cellulose anhydroglucose molar basis, said fibers having: a. an average dry fiber twist count of at least about 4.5 twist nodes per millimeter; b. an average wet fiber count of at least about 3.0 twist nodes per millimeter and at least about 0.5 twist nodes per millimeter less than said dry fiber twist count; c. an average isopropyl alcohol retention value of less than about 30%; and d. an averge water retention value of between about 28% and about 50%.

Claim 14

Dependent Claim 159 words

An absorbent structure comprising a mass of individualized, chemically stiffened, curled cellulosic fibers and a crosslinking agent, wherein said crosslinking agent is selected from the group consisting of C 2 -C 8 dialdehydes, C 2 -C 8 dialdehyde acid analogues having at least one aldehyde group, and oligmers of said dialdehydes and dialdehyde acid analogues, said fibers chemically stiffened by reaction with from about 0.75 mole % to about 2.0 mole % of said crosslinking agent, calculated on a cellulose anhydroglucose molar basis, said fibers having: a. an average dry fiber twist count of at least about 4.5 twist nodes per millimeter; b. an average wet fiber count of at least about 3.0 twist nodes per millimeter and at least about 0.5 twist nodes per millimeter less than said dry fiber twist count; c. an average isopropyl alcohol retention value of less than about 30%; and d. an averge water retention value of between about 28% and about 50%.

Claim 15

Dependent Claim 22 words

An absorbent structure as in claim 12, wherein said fibers have an average dry fiber curl factor of at least about 0.30.

Claim 16

Dependent Claim 19 words

An absorbent structure as in claim 13, wherein said average dry fiber curl factor is at least about 0.50.

Claim 17

Dependent Claim 56 words

An absorbent structure as in claim 12, wherein said average dry fiber twist count is at least about 5.5 twist nodes per millimeter and said average wet fiber twist count is at least about 4.0 twist nodes per millimeter and at least about 1.0 twist node per millimeter less than said average dry fiber twist count.

Claim 18

Dependent Claim 37 words

An absorbent structure as in claim 15, wherein said average dry fiber twist count is at least about 6.5 twist nodes per millimeter and wet fiber twist count is at least about 5.0 twist nodes per millimeter.

Claim 19

Dependent Claim 19 words

An absorbent structure as in claim 12, wherein said average isopropyl alcohol retention value is less than about 27%.

Claim 20

Dependent Claim 20 words

An absorbent structure as in claim 17, wherein said average water retention value is between about 30% and about 45%.

Claim 21

Dependent Claim 23 words

An absorbent structure as in claim 18, wherein said fibers have an average water retention value of between about 35% and about 42%.

Claim 22

Dependent Claim 65 words

An absorbent structure as in claim 19, wherein said average dry fiber curl factor is at least about 0.50, said average dry twist count is at least about 5.5 twist nodes per millimeter, and said average wet twist count is at least about 4.0 twist nodes per millimeter and is at least about 1.0 twist node per millimeter less than said average wet twist count.

Claim 23

Dependent Claim 37 words

An absorbent structure as in claim 20, wherein said average dry fiber twist count is at least 6.5 twist nodes per millimeter and said average wet fiber twist count is at least 5.0 twist nodes per millimeter.

Claim 24

Dependent Claim 28 words

The absorbent structure of claim 21 wherein said crosslinking agent is selected from the group consisting of glutaraldehyde, glyoxal, and glyoxylic acid, said fibers being individually stiffened therewith.

Claim 25

Dependent Claim 13 words

An absorbent structure as in claim 22, wherein said crosslinking agent is glutaraldehyde.

Claim 26

Dependent Claim 37 words

An absorbent structure as in claim 11, wherein said structure has a dry density and an equilibrium wet density, both calculated on a dry fiber weight basis, said dry density being greater than said equilibrium wet density.

Claim 27

Dependent Claim 37 words

An absorbent structure as in claim 21, wherein said structure has a dry density and an equilibrium wet density, both calculated on a dry. fiber weight basis, said dry density being greater than said equilibrium wet density.

Claim 28

Dependent Claim 37 words

An absorbent structure as in claim 23, wherein said structure has a dry density and an equilibrium wet density, both calculated on a dry. fiber weight basis, said dry density being greater than said equilibrium wet density.

Claim 29

Dependent Claim 29 words

The absorbent structure of claim 12, 20, 21, 23, 24, 25, or 26 further comprising polymeric gel forming material admixed through at least a portion of said absorbent structure.

Claim 30

Dependent Claim 27 words

The absorbent structure of claim 12, 20, 21, 23, 24, 25, or 26 further comprising polymeric gel forming material adjacent to a surface of said absorbent structure.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1993-02-05	1993-08-07	1994-02-06	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1997-02-05	1997-08-07	1998-02-06	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	2001-02-05	2001-08-07	2002-02-06	$7700.00	Window Closed / Lapsed

Twisted, chemically stiffened cellulosic fibers and absorbent structures made therefrom

Abstract

Inventors

Bibliographic Details

Claims Analysis

References Cited (Backward Citations)

USPTO Annuity & Maintenance Windows

Assigned Categories & Tags

Assign Category Tag