Note: Descriptions are shown in the official language in which they were submitted.
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NON-WOVEN FABRIC COMPRISING BUDS AND BUNDLES CONNECTED
BY HIGHLY ENTANGLED FIBROUS AREAS A~D MEI~IODS OF
MANUFACTURING THE SA~
The present invention relates to a non-woven fabric and
more particularly to pattern non-woven fabrics made from~
a layer of fibrous material such as a fibrous web, wherein ~ ;
the individual fiber elements are capable of movement
under the influence of applied fluid forces. The patterns
in the fabric are patterns of groups of fiber segments.
One pattern comprises pivotal~packings of fiber segments
or nubs protruding out of the plane of the fabric along
with a yarn-like fiber bundle with the nub connected to `~
the bundle by groups of aligned fibers extending from the
nub.
A second pattern comprises highly entangled areas of
fibers, where the fibers interentangle in the longitudinal;
and transverse directions and through the thickness of the~
fabric. The second pattern is continuous and extends
throughout the fabric and connect~3 the discontinuous
pattern described above.
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For a number of years there have been known various types
of foraminous aperiured non-woven fabrics made by
processes involving the rearrangement of fibers~in the
starting web or layer of fibers. Some of these fabrics
and methods of manufacture are illustrated, shown and
described in U.S, Patent ~os, 2,862,251, 3,081,500, and
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3,081,515, The fabrics disclosed and cl~imed in the
patents just listed contained apertures or holes or other
areas of low fiber density outlined by interconnected
bundles of fibrous elements, wherein the fiber se0ments
within the bundle are closely associated and parallel and
have a yarn-like configuration,
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Another type of apertured non-woven fabric is shown,
illustrated, and described in U,S, Patent No. 3,033,721.
The fabric disclosed in that patent comprises protuberant
pivotal packings of fibers, which protrude out of the
plane of the fabric and are interconnected by flat ribbon~
like groups o~ aligned fiber portions which define low
fiber density areas therebetween, Such fabrics are
generally termed ~rose-bud", non-woven ~abrics, ;
Another type of apertured non-woven fabric is shown,
illustrated and described in U,S. Patent 3,485,706. The
fabric disclosed in that patent comprises highly entangled
fiber areas. The fibers have been so highly entangled in
~rose-bud~ type configurations or similar configurations
that the fabric is strong without requiring the addition
of binder.
Still further types of fabrics are disclosed in U.S.
Patents 3,682,756 and 3,681,183 which disclose various
combinations of yarn-like bundle patterns and pr~otuberant
pivotal packings or nrose-bud~ type patterns in various
combinations to produce uniquel~ patterned non-woven
fabrics, Most all of these rearranged non-woven fabrics
are made by supporting a fibrous web or layer of fibers on
a permeable backing member and applying sets of opposing
fluid forces to the layer while thus supported, The fluid
by which the forces are applied passes through the layer
over the backing member and through the backing member to
pack various groups oE fibrous elements and place these
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elements into closer proximity and substantial parallelism
to form bundles of fiber segments. To produce "rose-bud"
fabrics, the layer is supported on a perforated backing
member and again fluid is applied over the layer while
supported, A vacuum or suction means is placed behind the
perforated member to draw the fluid through the layer and
out through the perforations,
Summary_of the Invention
I have discovered a novel non-woven fabric which comprises
a layer of intermingled fibers with the fibers arranged to
define a plurality of,patterns, The first pattern is one
of discontinuous areas, Each of these areas has at least ~`~
one pivotal packing of fiber segments, which protrude out
of the plane of the fabric. The pivotal packin~ comprises
fiber segments which are interentangled and in helter-
skelter arrangement. The discontinuous areas also include
a yarn-li]ce bundle, The yarn-like bundle comprises fiber
segments, wherein the segments are closely associated and
generally parallel to the longitudinal axis of the bundle~
The bundle and pivotal packed area are connected to each
other by flat ribbon-like groups of aligned fibers which
extend outwardl~ from the pivotal packing to the fiber
bundle, The discontinuous pattern is interconnected
throughout the fabric by a continuous pattern o~ highly
entangled fiber portions, The fibers in this continuous~
pattern are highly entangled in the longitudinal direction ;~
of the fabric, the transverse direction of the fabric
and throughout the thickness of the fabric to producê
a strong fabric with considerable esthetic appeal,
My new fabric has a substantial uniformity of pattern of
areas and has excellent strength characteristics and may`
even be used without any additional binder. If additional
binder is required, it only need be used in minor amounta
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to produce products that are very soft and have good
absorptive capacity. Also, the new non-woven fabric of
the present invention unexpectedly has a depth or three
dimensional appearance which makes it look as though it
were a multi-layered fabric. In a preferred embodiment, ~ -
my new fabric has what appears to be cones extending
through the thickness of the fabric with the wide diameter
of the cone formed by very dense areas on one surface of
the fabric and which extend to a pivotal protuberance on
the other surface of the fabric. This unexpected three
dimensional or multi-planar configuration provides the
fabric with a "cling" and with excellent softness
characteristics.
Surprisingly, my new fabric has a relatively low bulk
density while maintaining ~ood tenacity. This is
unexpected since generally as tenacity is increased by
increasing the energy used to produce the fabric, the
thinner and less bulkier the fabric becomes. However, my
new fabric, while having a tenacity of at least 0.5 pounds~
per inch per 100 grains per square yard, will have a bulk
density in the range of from 0 04 to 0.084 grams per cubic
centimeter, Furthermore, my new fabric has good absorbency ;
characteristics in that it will have a capacity ~or ab~
sorbing liquid of at least 7 1/2 times its own weight.
Method of Makinq the Fabric of This Invention
In manufacturing my new non-woven fabric, a starting layer
of fibrous material, the individual fibrous elements of `
which are capable of movement under the influence of
applied fluid forces is subjected to fluid, rearranging ; -
forces, preferably liquid, while the layer is supported on`
a permeable backing member. The backing member has a
predetermined topography. The fluid flows over the
surface and through the backing member. The fluid is
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directed against the fibrous layer while it is on the
backing member through a member which is apertured. The
fibrous layer is placed on the backing member and the
apertured member placed on top of the fibrous layer and
fluids directed through the apertured member to act on the
fibrous layer and then out through the permeable backing
member. The apertured member is removed and the backing
member with the fibrous material thereon is placed beneath
an apertured member for a second time. It may in fact be
the same apertured member as the first time but the second
time there is a different registry between the areas of
the fibrous layer and backing member and apertures. The
fibrous layer is again treated with fluid passing through ;
the apertured member through the fibrous layer and out
through the permeable backing member. The fluid flow
causes counteracting components of force to act beneath
the land areas in apertured members to rearrange fibers
into yarn-like bundles. The fluid flow also causes other ~ :
components of force to act on the fibrous layer to pack
fiber portions into groups of pivotal packings in
accordance with the pattern of pexmeable areas in the
backing member. The fluid flow causes yet other
components of force to act on the fibrous layer to form
a continuous interconnecting pattern of highly entangled
interlaced ~ibers in the longitudinal and transverse
direction of the fabric as well as through the thickness :
of the fabric.
Surprisingly, the above described plural treatment of the
fibrous layer wick the drum and belt out of registry in
each subsequent treatment and does not densify the fibrous
layer over the original treatment. What this plural ~ ;
treatment does accomplish is to increase the tenacity of
the fibrous layer without increasing the bulk density of
the fabric produced to unexpectedly produce a bulkier and
highly absorbent productO
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The basic method and apparatus for making the fabric of
this invention are shown and described in U.S. Patent
2,862,251 issued December 2, 1958. Specific features
peculiar to the method and apparatus for making the
fabrics of the present invention are described in detail
below.
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The starting material used with the method and apparatus
for making -the fabrics of this invention can be any of the
standard fibrous webs such as oriented card webs, isowebs, ;~
air-laid webs or webs formed by liquid deposition. The
webs may be formed in a single layer or by laminating a ;
plurality oE the webs together. The fibers in the web may
be arranged in a random matter or may be more or less
oriented as in the card web. The individual fibers may be
relatively straight or slightly bent. The fibers interseet
at various angles to one another such that adjacent fibers
come into contact only at the points where they cross. ~ `~
The fibers are capable of movement under forces applied
by fluids such as water, air, ete.
To produce the fabric having the characteristic hand and
drape of a textile fabric, the starting material used with
the method and apparatus o~ this invention may comprise
natural fibers such as cotton, flax, etc.; mineral fibers
such as glass, artificial fibers such as viscose~rayon,
cellulose acetate, etc., or synthetic fibers such as the
polyamides, the polyesters, the acrylics, the polyolefins,
etc., alone or in combination wit'n one another. The
fibers used are those commonly considered textile fibers, ;
that is, generally having a length from about 1/4`' to
about 2 to 2 1/2"~ Satisfactory products may be produced ;
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in accordance with this invention from starting webs
weighing between 80 grai~ns per square yard to 2,000 grains
per square yard or higher.
The apertured forming means used with the method and
apparatus for making the fabrics of this invention has
apertures disposed longitudinally and transversely across
its area with land areas lying between the apertures. The
forming apertures may have any desired shape, that is,
round, square, diamond, oblong, free form, etc. and may be
arranged in any desired pattern over the surface of the
forming means.
The land areas of the aperture forming means that lie
between and interconnect the forming apertures may be
narrow or broad in comparison to the forming apertures
as desired.
As two aperture forming means are used in the method and
apparatus of the present inventioII, the aperture forming
means may either be the same or different in size, shape,
pattern, or any combination ther~30f of the apertures.
The backing means is a foraminous member and is usually
a woven wire mesh with hills and valleys where the wires
cross each other. The wires or filaments are woven fairly
loose to produce openings or foramen in the backing member
and depending on the properties of the filaments or wires
used, the configuration where one wire crosses another
wire may vary both in depth and slope. ~ ;
The rearranging fluid for use with this invention is
preferably water or similar liquid or it may be other
fluids such as gas as described in U.S. Patent 2,862,251.
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According to a further broad aspect of the present
invention there is provided a non-woven fabric with a
plurality of patterns of groups of fiber segments that
alternate and extend throughout the fabric. The non-woven
fabric comprises groups of fiber segments in discontinuous
portions of the fabric. The discontinuous portions form a
first pattern. Each of the groups include at least one nub
of fiber segments interentangled in helter-skelter arrange-
ment, and the nub protrudes out of the plane of the fabric.
Each of the groups also includes at least one yarn-like
bundle of fiber segments wherein the fiber segments are in
close proximity and substantial parallelism to one another.
The first discontinuous portions of the fabric are bound ~
and interconntected by a continuous highly entangled, inter-
laced fibrous area. The continuous portion forming a second
pattern and the fibers in the continuous portion are entangled
in substantially all directions including the thickness of
the fabxic. The fabric has a bulk density of from 0.04 grams
per cubic centimeter to 0.084 grams per cubic centimeter and
a tenacity of at least 0.5 pounds per inch per 100 grams per
square yard.
According to a still further broad aspect of the present
invention there is provided the method o~ producing a non-
woven fabric having a plurality of patterns of groups of
fiber segments that alternate and extend throughout the
fabric from a layer of starting fibrous material, the indi-
vidual fibrous elements of which are capable of movement
under applied fluid forces. The method comprises supporting
the s-tarting material on a foraminous member having a
predetermined topography. The starting material is treated
while so supported with a first pattern of longitudinally
and transversely spaced and simultaneously flo;~ing fluid
streams. The fluid streams are removed while maintaining
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the treated material on the foraminous member. The material
is treated a second time with a second pattern of longitu-
dinally and transversely spaced and simultaneously flowing
f luid streams. The second pattern is out of register with ~;
the first pat-tern of longitudinally and transversely spaced
f luid streams.
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Brief Descr ption of Drawinqs
The invention will be more fully described in conjunction
with the accompanying drawings, wherein:
Figure 1 is a photomicrograph of a fabric of the present
invention at an original enlargement of 16 times;
Figure 2 is a photomicrograph of another fabric of the
present invention at an original enlargement of 4 times,
Figure 3 is a diagramatic showing an elevation of one type
of apparatus for carrying out the method for producing
fabrics of the present invention,
Figure 4 is a view in perspective of a portion of a back-
ing means that can be used in the apparatus of Figure 3,
Figure 5 is a cross-sectional view taken along line 5-5
of Figure 4,
Figure 6 i9 a cross-sectional view taken along line 6-6
of Figures 4 and 5.
Detailed Description of Specific ~ b~ Ihe
Inve~tion
Referring to photomicrograph in E`igure 1, there is shown a
non-woven fabric 10 of the present invention. The fabric
comprises a regular or predetermined pattern of areas in
discontinuous portions of the fabric. Each area 11 is
circular and has at least one pivotal packing of fiber
segments 12~ The pivotal packings protrude out of the
plane of the fabric. The fiber segments in the pivotal
packings are interentangled and in helter-skelter arrange-
ment. The ~ivotal packings are attached to a yarn ~like
bundle 13. The yarn-like bundle comprises fiber segments
in substantial parallelism and in close proximity. The
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packings and bundles are connected by groups of aligned
fibers 14 which extend from the pivotal packings to the
yarn-like bundles. In Figure 1, the circular areas are ~ -
found and interconnected throughout the fabric by highly
entangled fibrous areas 15~ The highly entangled and
interlaced fibrous areas extend in all directions of the
fabric including the thickness of the fabric.
Referring to the photomicrograph in Figure 2, there is
shown another non-woven fabric 20 of the present inven- ~
tion. In this embodiment, the areas 21 containing the ~ -
pivotal packings 22 of fibers are substantially square
in configuration. The square areas contain pivotal pack-
ing 22 of entangled, helter-skelter fiber arrangement
and yarn-like fiber bundles 23 with fiber segments in
close proximity and substantial parallelism. The pivotal
packings 22 and the fiber bundles 23 are connected to one
another by groups of ribbon-like fiber segments 24.
The square areas are bound and interconnected throughout
the fabric by highly entangled, interlaced fiber segments
25 with the fibers being interlaced in all directions
including the thickness of the fabric.
In both Figures 1 and 2, it can be seen that portions of
fibers extend into the discontinuous areas and in many
instances through the discontinuous areas.
The fabrics produced in accordance with the present
invention have a bulk density range of between 0.04 and
0.084 grams per cubic centimeter. On the average, the
fabrics of the present invention have a bulk density of
0.052 to 0.078 grams per cubic centimeter. The bulk
density of the fabric is determined by measuring the
fabric thickness as set forth in the ASTM Standard Method
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for Measuring Thickness of Textile Materials D1777-64.
The weight in grams of a specific size sample of the
fabric is also measured and the bulk density calculated
by dividing the weight per unit area by the thickness.
The fabrics of the present invention have good tenacity,
that is, tenacities of at least 0.5 pounds per inch of
width per 100 grains per square yard. Generally, the
tenacities of fabrics produced in accordance with the
present invention will be in the range of from 0.5 to
0.75 pounds per inch of width per 100 grains per square
yard. The tenacity is determined by measuring the break-
ing load of the fabric in both the machine and cross
directions using the one inch strip test method set forth
in ASTM Standard Test Method for Breaking Load and
Elongation of Te~tile Fabrics D 1682.64.
The tenacity of the fabric is then calculated by finding
the square root of the product of the machine direction
breaking load times the cross direction breaking load.
Since the new and improved fabrics of the present inven-
tion have low bulk densities, they have good absorbent
capacities. Fabrics of the present invention hold at
least 7 1/2 times their weight of water and in some
instances as much as 10 1/2 times their weight of water.
On the average, the fabrics of the present invention hold
about 9 times their weight of water. The absorbency of
the fabric i.s determined by taking four, 4 inch by 4 inch
samples, of the fabric and determining the weight of
samples in grams at ambient conditions. The 4 layer
sample is placed in a tray and a 400 gram 4 inch by 4
inch metal plate with a 3/4 inch diameter center hole
placed on ~p of the sample.
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Water from a burnette is poured through the center hole as
fast as possible without overflow. Water is added until
the sample is saturated and the sample allowed to absorb
for 15 seconds. The tray is tilted 30 degrees and all
e~cess water that drains in one minute is collected in a
graduated cylinder. The absorbent capacity of the sample
is then calculated by subtracting the milliliters of water
collected in the graduated cylinder from the milliliters
of water added from the burnette and dividing that result
by the dry weight of the sample in grams.
Description of Machine and Method for Makinq Fabrics of
My Invention
Referring to Figure 3 in the drawings, there is shown one
form of apparatus for carrying out methods to produce
products in accordance with the present invention. Full
particulars of this apparatus, except for the details of
the novel aspects of the present invention, including
methods of mounting, rotating, etc., are fully described
in U.S. Patent 2,862,251 issued December 2, 1958. In
view of this refexence, the apparatus of Figure 3 will be
described in general terms insofar as essential elements
are the same in the patent just mentioned, and the novel
elements of this apparatus, that is, the removal and
xeplacement of the backing or supporting member will be
described in more detail.
The apparatus includes a rotatable perforated drum 30
suitably mounted on flange guide wheels 31 and 32. The
drum has apertures 33 uniformly spaced over its entire
surface. The guide wheels are mounted for rotation on
shafts 34 and 35. Inside the drum there is stationarily
mounted along the full width of the drum, a manifold 36
to which a fluid is supplied through conduit 37. On one
side of the manifold is a series of nozzles 38 for
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directing the fluid against the inside surface of the drum.
In the embodiment shown, there is a second manifold 36a
for directing the fluid against the inside of the drum at
another portion along the inside perimeter of the drum.
A backing or supporting member 40 is arranged to travel
with the drum 30 as will be described hereinafter. (The
terms "backing member`' and "support member" are used inter-
changeably throughout this description J )
The support member as shown in the embodiments in Figures
4, 5, and 6 is foraminous. The support member 40 is
formed from coarse woven screen preferably metal, or it
may be metal in one direction and textile filaments in the
other direction or other coarse woven screens. The wires
51 running vertically in Figure 4 are straight, while
wires 52 running horizontally weave alternately over and
under wires 51. Protuberances 53 are present throughout
the foraminous screen as the topmost part of each "knee"
of a given strand 52 of the screen that is formed as the
strand weaves over and under the strands 51 that lie
perpendicular to it.
As a given strand 52 slants downward to pass under a
strand 51 perpendicular to it, it crosses two other
strands 52 disposed on either side of it, as those strands
slant upward to pass over the same perpendicular strand ~ ;~
that the given strand will pass under. Each series of
such "crossing points" 54 forms a trough, such as trough
55, formed by crossing points 54 in Figures 4 and 5 that
lie between adjacent protuberances 53. The effective
shape of trough 55, as can be best seen in Figure 5 (which
shows a cross-section of element 40 of which a plan view
is given in Figure 4) is substantially an inverted triangl-.
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A series of slightly deeper troughs 56 is formed between
adjacent protuberances 53 but extending at right angles to
troughs 55. As best seen in Figure 6, the bottom of each
trough 56 is formed by portions of straight strands 51,
with successive protuberances 53 on each side of the
trough forming the tops of the troughs. As seen in Figure
6, the effective shape of trough 56 may be characterized
as a shallow "U" shape.
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As shown in Figure 4, plurality of troughs 55 and a plura-`~
lity o~ protuberances 53 alternate in one direction across
the surface of the backing means. Figure 4 also shows a
plurallty of troughs 56 and a plurality of protuberances;
53 alternate in a direction perpendicular to troughs 55.
Hence, a plurality of troughs and a plurality of protube-
rances alternate in both the longitudinal and transverse
directions of the backing means 50.
The backing member 40 passes about the drum and separates~
from the drum at guide roll 41 which rotates on shaft 42.
The backing member passes downwardly around guide roll 43 ~ ~ ;
rotating on a shaft 44 and then rearwardly over vertically
adjustable tension and tracking guide roll 45 rotating on
a shaft 46 and then around guide roll 47 on a shaft 48.
The member passes upwardly and around guide roll 49
rotating on shaft 50 to be returned about the periphery
of the drum.
The drum and supporting belt provide a rearranging zone
between them through which a fiber starting material may
move to be rearranged under the influence of applied fluid ;~
forces to a non-woven fabric having a plurality of
patterns throughout its area. Tension on the support
member is controlled and adjusted by the tensioning and ;~
tracking guide roll. The guide rolls are positioned in
slidable brackets which are adjustable to assist in the
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maintenance of the proper tension of the support member.
The tension required will depend upon the weight of the
fibrous web being treated and the amount of rearrangement
and patterning desired in the final product.
Apertured drum 30 rotates in the direction of the arrows,
show, and support member 40, moves in the same direction
and at the same peripheral speed as the drum, and within
the indicated guide channels so that both longitudinal and
lateral translatory motion of the backing means, the
apertured forming means, and the fibrous layer with
respect to each other are avoided. The fibrous material
60 to be rearranged is fed between the drum and support
member at point A, passes through the first fiber
rearranging zone where fluid rearranging forces are applied
to it. The backing member with the fibrous material is
then removed from the drum at point B and is placed back
onto the drum at point C so that there is now a new rela-
tionship between the apertures in the drum, the fibrous
material, and the backing member and is now passed through
a second rearranging zone for a second rearrangement. The
fabric in its new form is removed from between the support
member and the aperture drum at point D. As the fibrous
material passes through the fiber rearranging zones, a
liquid such as water is directed against the inner surface
of rotating apertured drum through the nozzles mounted ~ ~
inside the drum. The liquid passes through drum apertures ~ -
and through the fibrous web and, hence, through the backing ~ -
means thereby affecting rearrangement of the fibers of the
web. In the first rearranging zone, the liquid passes ;
through in one manner and in one relationship of apertures,
fibers and backing member, and in the second rearranging
zone, the relationship of the apertures, fibers and backing
member has been altered to obtain a second type of rearrange-
ment.
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Vacuum assist boxes 64 and 65 are located against the
outside surface of the backing means. The vacuum boxes
have a slotted surface located closely adjacent to the
outer surface of the belt and through which suction is
caused to act upon the web. Suction thus applied assists
in rearrangement of the fibers as the web material passes
through the rearranging zones. In addition, it serves to
help dewater the web and prevent flooding during fiber
rearrangement.
The directions the streams of rearranging fluid projected
through the apertures of the drum 30 take as they move
into and through the fibers web determine the types of
forces applied to the fibers and, in turn, the exten~
of rearrangement of the fibers. Since the directions the
streams of rearranging fluid take after they pass through ~the apertures 33 are determined by the foraminous backing ~ ~;
member, it follows that lt is a combination of the ~ `
patterns in the drum and backing member that at least in
part determine the patterns of ho:Les and other areas of ~ ;low fiber density in the resulting fabric.
The rearranged web or fabric of the present invention may
be treated with an adhesivè dye or other impregnating
printing or coating material in a conventional manner.
For example, to strengthen the rearranged web, any suit~
able adhesive bonding materials or binders may be included ~ ~ -
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in an aqueous or non~aqueous medium employed as the
rearranging fluid. Or an adhesive binder may, if desired~
be printed on the rearranged web to provide the necessary~
fabric strength. Thermoplastic binders mayj if desired,
30 be applied to the fibrous web in powder form before, during,
or after rearrangement, and then fused to bond the fib<rs.
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The optimum binder content for a given fabric according to ~ -
this invention depends upon a number of factors, including
the nature of the binder material, the size and shape of
the binder members and their arrangement in the fabric,
the nature and length of the fibers, total fiber weight
and the like. In some instances, because of the strength
of the fibers used or the tightness of the interentangled
areas connected to the discontinuous portions, no binder
at all need be employed to provide a usable fabric.
Also, wood pulp fibers may be incorporated along with the
textile fibers and rearranged along with the textile fihers~
Although I have described a single drum and belt or backing
means unit, wherein I take the belt away from the drum and `~ ;;
then place it back on the drum, two drums and belts in
series or more may be used to accomplish the same objective.
I can also use two drums and one helt with the belt going ;
about a substantial portion of the periphery of one drum,
removed therefrom, and then about: a substantial portion
of the periphery of a second drum. Depending upon the
number of times that I remove the belt and web from the
aperture means and replace it thereto and, of course on the~
amount of pressure used in the nozzles will determine the
ultimate strength of the final fabric.
The fluid may be applied to the material at anywhere from
about 30 pounds per square inch up to 200 to 250 pounds
per square inch or even higher, though higher pressures are~
not required.
The following are illustrative examples of the method and
apparatus of this invention to produce the novel patterned
non-woven fabrics of the present invention.
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Example I
In apparatus as illustrated in Figure 3, a web of loosely
assembled fibers, such as may be obtained by air-laying
apparatus, is fed between an apertured forming drum and
the backing means, The web weight is about 620 grains per~
square yard and its fiber orientation ratio approximately
one to one. The web is made from viscose rayon fibers
approximately 1 1/2 inches long of 1,5 denier.
Apertured forming means has about 120 substantially round~
holes per square inch, each approximately 0,065 inch in
diameter. Thq holes are arranged in a staggered pattern
over the forming means. Each aperture is spaced on
approximately 0,09 inch centers from lmmediately adjacent
apertures on the drum both about the periphery of the
drum and transverse of the drum.
The backing member is a woven polyester screen of approxi~
mately 23 by 23 mesh or substantially 529 openings per
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square lnch.
The web is placed on the backing member and water is
20 projected from nozzles through apertures in the apertured
drum and thence through the fibrous web and the backing ~
member into the vacuum assist box. The apertured forming
means, web and backing means have a linear speed of 30
feet per minute.
Approximately 180 gallons per minute of warm water at
110F, and pressures of about 190 psi are projected
against the drum, The backing member with the rearranged
web thereon is removed from the drum and placed back on
the drum as shown in the drawing, Water is again projected
from nozzles through apertures in the apertured drum and
through the fibrous web and out the backing member into the
vacuum assist box. Approximately 180 gallons per minute of ~ ,
water at pressures of about 190 psi are used in the second
treatment,
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The nozzles used in both treatments comprise four rows on
one inch cen-ters. Fourteen nozzles per row are used with
the nozzles staggered in each row. Each nozzle has a
diameter of 75 mils.
With the conditions indicated, good fiber rearrangement
and entanglement are obtained, and a non-woven fabric
such as shown in the photomicrograph in Figure 1 is produced.
The fabric produced is tested for tensile strength in both
the machine direction and the cross direction of the final
fabric. The machine direction tensile strength is 5 pounds
and the cross directional tensile strength is 4.25 pounds.
The fabric may be used as a wiping cloth or as a cover for
an absorbent product or similar end uses. The fabric is
very soft and absorbent.
Exa~ple II
Utilizing -two rearranging drums arranged in series, a web
of loosely assembled fibers, such as may be obtained by
air-laying apparatus, is fed between the first apertured
forming drum and the first backing means. The average web
weight is 537 grains per sq. yard. The web has an average
fiber orientation ratio of approximately 1.5 to 1. The
web is made ~rom rayon fibers approximately 1 1/2 inches
long and 1 1/2 denier. Both apertured formations, that is,
both the first and second drum, have about 225 substan-
tially round holes per square inch with each hole approxi-
mately .045 inch in diameter. The holes are arranged in
a square pattern over the forming means. The backing member
used on both drums is a woven screen with polyester filaments
running in a longitudinal direction of the screen and steel
filaments running in the transverse direction of the screen.
The mesh of the screen is 22 x 24. The web is placed on
29~
-- 19 --
the backing member and water projected from nozzles through
the apertures in the apertured drum, and then through the
fibrous web and the backing member. The web is then fed
onto the second backing member and the process repeated.
The apertured forming means, web, and backing have a linear
speed of approximately 100 feet per minute. Approximately
2500 gallons per minute of warm water at 150F, and
pressures of about 200 psi are projected through the weh,
1250 gallons being projected in the first drum, and
approximately 1250 gallons being projected in the second
drum. In both drums, there are seven rows of nozzles with
40 nozzles per row spaced on 1" centers. Each nozzle has
a diameter of about 75 mils.
Two hundred thousand yards of fabric is produced and
samples tested for tenacity and bulk density. The tenacity
ranges from 0.515 to 0.593 lbs. per inch of width per 100
grains per sq. yard, and the bulk density ranges from .0517
to .0624 grams/cubic centimeter. The average absorbency
of the fabric is about 11 times its own weight. The fabric
may be used as an absorbent sponge.
Example III
A web of loosely assembled fibers such as may be obtained
by air-laying apparatus is fed between an apertured
forming dxum and a backing means. The web weight is about
700 grains/sq. yard and has a fiber orientation of
approximately 1 1/2 to 1. The web is made from viscose ~ ~ ;
rayon ~iber, approximately 1 1/2 inches long and 1 1/2
denier.
The forming means has about 112 substantially round holes
per square inch, each hole approximately 0.1 inch in
diameter. The holes are arranged in a staggered pattern.
- 20 -
The backing member used a woven polyester screen of
approximately 23 x 23 mesh or substantial 529 openings per
square inch. The web is placed on the backing member and
water is projected from nozzles through the apertures in
the apertured drum and thence through the fibrous web.
The apertured forming means, web, and backing means have
a linear speed of about 15 feet per minute.
Approximately 180 gallons per minute of warm water at
110F. and pressures of about 190 psi are projected
against the drum. The backing member with the rearranged
web thereon is removed from the drum and placed back on
the drum as shown in Fig.!^3 of the drawings. Water is
again projected from nozzles through apertures in the ~ sapertured drum and through the fibrous web. Approximately
180 gallons of water at a pressure of about l90 psi are
used in the second treatment. The nozzles used in both
treatments comprise 4 rows on 1`' centers. Fourteen
nozzles per row are used and nozzles are staggered in each~
row with each nozzle having a diameter of 75 mils~ The
fabric produced is tested for a tenacity and bulk density.
The tenacity of the fabric is 0.62 lbs. per inch per 100
grains/sq. yard and the bulk density of the fabric is .082
grams per cubic centimeter. The fabric is suitable as an
absorbent wiping cloth.
:~
Example IV
A web of loosely assembled fibers such as is obtained by
air-laying apparatus is fed between a first apertured
forming drum and a first backing means. The web weighs
about 700 grains per sq. yard and has a fiber orientation
of approximately 1 1/2 to 1. The web is made of viscose
rayon fibers, approximately 1 1/2 inches long and 1 1/2
denier. The first apertured forming means has about 233
substantially round holes per square inch, each approxi~
mately .0~5 inches in diameter. The holes are arran~ed
:,: :
:
3~
- 21 -
in a square pattern over the forming means. The first
backing member is a woven polyester screen of approxi-
mately 23 x 23 mesh or substantially 529 openings per
square inch. The polyester filaments used have a diameter
of .011 inches. The web is placed on the backing member
and water is projected from nozzles through the apertures
in the apertured drum and thence through the fibrous web.
The apertured forming means, the web, and backing means
have a linear speed of about 19 feet per minute. Approxi-
mately 180 gallons per minute of water at 110F. and
pressures of about 190 psi are projected against the drum.
The web is then passed around a second apertured forming
drum of the same construction as the first drum, but the
bac]cing member used on the second drum is a 6 x 6 polyester
screen with the polyester filaments having a diameter of
.039 inches. In the second rearranging step, approximately
180 gallons per minute of warm water at 110F. and pressures
of about 190 psi are projected against the drum. The
nozzles used in both treatments or projecting the water
comprise 8 rows of nozzles on 1" centers. Fourtee~n nozzles
per row are used and the nozzles are staggered in each row.
Each nozzle has a diameter of 75 mils. The fabric produced
is tested ~or both tenacity and bulk. The tenacity of the
fabric is 0.55 lbs. per inch of width per 100 grains/sq.
yard and the bulk density is .041 grams per cubic centi~
meters. The fabric is suitable for use as an absorbent
wipe.
The above detailed description has been given for
clearness and understanding only. ~o unnecessary limita-
tions should be understood therefrom, as modifications
will be obvious to those skilled in the art.
