Note: Descriptions are shown in the official language in which they were submitted.
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STABILIZATION OF FABRIC SURFACES
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims priority to U.S. Patent
Application No.
16/292,834, filed March 5, 2019. The entire contents of which are incorporated
herein by
reference.
TECHNICAL FIELD
[0002] Embodiments of the subject matter disclosed herein relate to
textile sheets
and floor coverings.
BACKGROUND
[0003] Textile flooring and other textile surface-coverings, for
example, wallcoverings
and upholstery, at a minimum require surface stability and abrasion
resistance. The
required surface stability and abrasion resistance are needed without
excessive hardening
of the surface and with the preservation of at least some "textile feel" or
textile look. Textile
flooring and textile surface-coverings often have textured three-dimensional
surfaces,
including highly textured or deeply embossed surfaces, and the structure of
the textured
three-dimensional surfaces needs to be maintained under severe end use
conditions
associated, for example, with flooring and upholstery.
[0004] While three-dimensionally formed fabrics and flat fabrics
with three-
dimensional textured surfaces may be abrasion-resistant, the fibers at the cut
edges of
these fabrics are typically not anchored sufficiently close to the exposed
tips at the cut
edges. These insufficiently anchored fibers tend to fray or "fuzz". When used
as a surface
covering such as a floorcovering or wall covering, the fabrics are grouped
together, forming
seams where adjacent cut edges meet. The grouped fabrics containing the
insufficiently
anchored fibers can develop visible lines of deterioration over time along the
seams, even
under conditions of normal use.
[0005] Flooring and related surface-covering applications utilizing
three-
dimensionally formed fibrous surfaces may also require materials and fabrics
that provide a
combination of breathability and simultaneous resistance to spilled fluid
penetration.
Breathability is usually defined as the transmission of a minimum amount of
water vapor
per 24 hrs, and resistance to spilled fluid penetration is usually defined by
the British Spill
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Test. According to the British Spill Test, water dropped onto a sheet of
material from a
height of 1 meter is required to fail to penetrate and breach the backside of
that sheet of
material for a period of at least 24 hrs.
[0006] Attempts at preventing liquids spilled on the surface of a
fabric or
floorcovering from breaching the backside have in the past used films or
membranes
attached to the bottom of the sheet. These arrangements however allow the
spills to
penetrate the top surface of the sheet of material, and only stop liquid
penetration at the
bottom. Therefore, the liquid penetrates into the lower layers of the sheet of
material. This
penetration into the lower layers can promote the formation and growth of
bacteria or fungi
within the lower layers.
[0007] Alternate attempts at using a film or membrane to resist the
penetration of
spills are described, for example, in U.S. Patent no. 5,965,232 to Vinod, U.
S. Patent No.
7,425,359 to Zafiroglu and U.S. Patent No. 7,431,975 to Zafiroglu. These
alternate
attempts place the membrane between a relatively thin textile fabric surface
and a
cushioning backing to form a preferably breathable floorcovering that allows
water vapors
to escape but that resists the penetration of liquids from spills. The
membrane is attached
to the structure with adhesive layers. These adhesive layers make obtaining
good
delamination resistance without limiting or fully blocking breathability
difficult. U.S. Patent
Application Publication No. 2013/0280486 to Zafiroglu discloses a liquid-
blocking
composite having a fibrous surface layer and a membrane placed directly under
the surface
layer. The surface layer may optionally have a texture deeper than the
original thickness of
the fibrous surface layer. The resulting liquid-blocking composite has low
breathability and
low water vapor transmission capability resulting, at least partially, from
the necessity to
use relatively high weights of adhesive.
[0008] Therefore, a need exists for fabrics, including highly-
textured fabrics, that
maintain high resistance to abrasion and surface deformation with use, and
preferably also
block the flow of liquids into the inner layers of the fabric while
maintaining a textile
appearance and textile texture. The fabrics would also preferably "breathe" to
allow the
transmission of water vapor. The highly-textured fabrics would have at least a
portion of
the surface fibers or surface loops exposed and free of adhesive or resin.
Therefore, the
surface would not lose its textile and fibrous feel by being hardened and
solidified. In
addition, a need exists for a reliable and flexible method to make these
highly-textured
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fabrics with special face aesthetics, or special properties such as microbial
resistance, or
soiling resistance.
SUMMARY
[0009] Exemplary embodiments are directed to methods for making
improved textile
fabrics and composites containing fabrics by using a plurality of low-melting
polymeric
particles deposited onto the surface. The deposited particles are guided into
the interstices
or gaps among the filaments, fibers or yarns exposed on the top surface of the
textile fabric
and also into the depressed areas of the textured top surface of the textile
fabric. The
particles are then activated with heat. The textile fabrics retain a textile
feel and may be
free-standing or attached to a backing. Suitable backings include, but are not
limited to,
bulky cushioning backings.
[0010] In one embodiment, the deposited low-melting polymeric
particles are
directed to the more desired areas of the surface of the fabric. In one
embodiment, the
plurality of low-melting polymeric particles is in the form of a fine powder.
In one
embodiment, the particles in the plurality of low melting particles include
coarser particles.
Suitable methods for forming or obtaining these coarser particles include
freeze-grinding
recycled polymeric textiles.
[0011] In one embodiment, the fabrics are flat but have a textured
surface. In one
embodiment, the textured surface is formed by yarns that loop into and out of
the surface,
creating elevated areas of yarn and depressed areas of yarn. In one
embodiment, the
surface is textured by embossing the surface with a three-dimensional pattern.
This three-
dimensional pattern creates raised areas of fabric and lowered areas of fabric
spaced
across the textile fabric at intervals larger than spacings among the elevated
areas or yarns
and depressed areas of yarns and extending into the textile fabric at depths
greater than
the depths of the depressed areas of yarns. In one embodiment, the raised and
lowered
areas of fabric extend to a depth that is greater than the original thickness
of the textile
fabric.
[0012] Both the type of particle and the technique used for
particle deposition are
selected to ensure that the deposited particles at the elevated areas of yarns
or the raised
areas of textile fabric stay primarily within a short depth under the top
surface of the textile
fabric. In one embodiment, the plurality of particles is deposited onto the
fabric by sifting,
with or without the help of vacuum, blowing of air, or vibration during or
after deposition.
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Particle size is chosen to approach, match, or exceed the dimensions of the
interstices or
gaps of the fabric surface to avoid excessive propagation below the top
surface. Therefore,
the particles, as deposited, remain on the top surface or within the upper
strata of the
fabric.
[0013] In one embodiment, the deposited particles are activated
with heat. Suitable
heat sources include, but are not limited to, radiant heat, hot air, and a
heated contact
surface applied with low pressure. In one embodiment, activation of the
deposited particles
is achieved by raising the temperature of the entire fabric to a level
sufficient to melt the
particles. In one embodiment, the particles are activated as the fabric is
embossed with the
three-dimensional pattern using a heated tool equipped with surface
projections. In one
embodiment, the particles are activated while the fabric is laminated to a
barrier layer or to
a backing layer. Lamination to the barrier layer or backing layer can be
achieved with a
relatively flat heated tool resulting in a composite with the general pattern
of the texture
originally formed in the fabric preserved. Alternatively, lamination to the
backing layer is
achieved with a three-dimensional heated tool forming deeper and coarser face
textures
that exceed the original thickness of the fabric. Embossing with a depth
exceeding the
original thickness of the fabric may utilize a soft and resilient back-up tool
such as silicon
rubber. Embossing against a conformable cushioning backing removes the need
for a soft
back-up tool as the fabric forms into the backing,
[0014] In one embodiment, the depth to which the resulting melted
particle resin
proceeds into the interstices or gaps among the surface fibers is controlled
by adjusting the
melt index of the deposited particles, e.g., the powdered resin. In one
embodiment, the
degree of propagation of melted particle resin into the textile fabric is
further controlled
through the selective application of hot air or cold air to the top surface of
the textile fabric.
In one embodiment, vacuum is applied under the fabric, i.e., to the bottom
surface opposite
the top surface, or under the composite containing the textile fabric as a
face layer to
control the degree of propagation of the melted particle resin into the
fabric.
[0015] Exemplary embodiments utilize limited amounts or levels of
particles to
prevent the addition of significant weight to the fabric while still improving
surface durability
at the elevated areas of yarns or raised areas of fabric, fuzzing resistance
at the cut edges,
and overall fluid penetration resistance. Limited levels of deposited
particles achieve these
improvements without eliminating the fibrous feel of the top surface of the
textile fabric or
composite into which the textile fabric is incorporated. In one embodiment,
the deposited
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particles are directed preferentially toward the lowered areas of a deeply
embossed textile
fabric to overcome the locally reduced resistance to fluid penetration by the
embossing
action.
[0016] In one embodiment, the textile fabric or floorcovering is
treated with repellent
solutions before or after the application of low-melt powder. In one
embodiment, elevated
areas of yarns are relieved of the extra deposited powder, and the extra
powder is moved
into the depressed areas of yams, by brushing, preferably as vacuum is applied
underneath.
[0017] In one embodiment, the exposed "high-profile" or "elevated"
areas of the top
surface of the fabric are stabilized by using a limited weight of particles or
powder
containing relatively coarser particles so that only parts of the elevated
areas of yarns are
covered by the resulting melted particle resin and parts are exposed to
preserve a textile
feel.
[0018] In one embodiment, the particles, are sifted upon the
textile fabric. In another
embodiment, the particles are incorporated into a liquid, e.g., water, and the
suspension is
applied to the top surface of the fabric. In one embodiment, an additional wet
brushing with
liquid free of particles is applied to the top surface of the textile fabric
in the elevated areas
of yams or raised areas of textile fabric to drive particles into the fiber
interstices before the
textile fabric is dried and the particles are melted. The liquid in the
suspension can be
evaporated following application, for example, by heating in an oven, using
radiant heat,
applying a vacuum or blowing hot air.
[0019] In one embodiment, the depth of penetration of the particles
is regulated by
selecting the size of the particles in comparison to the size and density of
the fibers or
yarns on the surface of the fabric. In one embodiment, vacuum is applied to a
bottom
surface of the fabric opposite the top surface as the fabric is vibrated
during or after the
deposition of the particles. Vacuum and vibration are also used to control the
depth of
penetration of the particles. In one embodiment, the applied particles have
the same size.
Alternatively, particles having different configurations, compositions or
densities are applied
simultaneously or in consecutive stages. In one embodiment, a mixture of
particle sizes is
used to allow some of the finer particles to penetrate the surface fibers or
yarns while some
of the coarser particles stay over the top surface. This mixture of particles
further improves
the abrasion resistance of the top surface. In one embodiment, the coarser
particles settle
at the depressed areas. After heat is applied to melt the coarser particles,
the resulting
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melted particle resin remains locally above the fibers at a lower profile than
the elevated
areas of yarns or raised areas of fabric without causing the loss of textile
and fibrous
surface aesthetics.
[0020] Suitable particles include, but are not limited to, fine
polymeric powders
commercially used in processes such as the bonding of non-wovens and coarser
powders
produced by grinding low melt polymers including polymers contained in
recycled fabrics or
floorcoverings. These powders contain particles having a range of particle
sizes suitable for
use with the fabrics. Suitable particles also include particles derived and
extracted from
recycled textiles containing low-melting fibers or films grounded into
appropriately fine
particle or powder size.
[0021] In one embodiment, non-melting fine elements are mixed with
the plurality of
particles either before or after the application of the particles in order to
obtain special
effects. These fine elements and desired effects include colored particles for
aesthetic
purposes, hard particles to increase resistance to abrasion, and particles
reacting to
moisture or heat to produce special visual or functional effects, including
but not limited to
breathability, moisture absorbency and moisture repellency at the surface.
[0022] In one embodiment, the original fabric contains a fluid
barrier layer that upon
deep embossing stays intact at the elevated areas of yarns and raised areas of
textile
fabric but is perforated and compromised at the highly compressed and indented
lowered
areas of textile fabric. Preferential deposition of powder into the lowered
areas of textile
fabric partially or totally seals the compromised lowered areas without
seriously affecting
the fibrous feel of the raised areas.
[0023] In one embodiment, particles having at least one of larger
sizes and lower
melt indexes that tend to stay on the top surface are combined with, preceded
by, or
followed by finer or higher melt-index particles that tend to penetrate in
order to create
special surface effects. In one embodiment, the particles include a mixture of
ground
recycled high-melt and low-melt fabrics, textiles or polymers, mixed with at
least one of low
melt powders, high melt powders, other non-melting particulates and special-
effect
particulates. These additional powders are added to affect one or more of
color, abrasion
resistance, surface absorbency, repellency and bacterial resistance among
other surface
properties.
[0024] Exemplary embodiments are directed to a textile fabric
having a plurality of
yarns. The yarns have a yarn melting point. The yarns include upper parts
adjacent a top
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surface of the textile fabric. A plurality of filaments forms the yams with a
plurality of gaps
disposed among the filaments. The textile fabric includes a plurality of
elevated areas of
yarns and depressed areas of yarns formed by the plurality of yarns looping in
and out of
the fabric. Melted particle resin resulting from a plurality of particles
being dispersed in gaps
located in the elevated areas of yams and melted is contained in the textile
fabric. The
plurality of particles has a particle melting point lower than the yarn
melting point. The
elevated areas of yarns include sections of filaments free of melted particle
resin. In one
embodiment, the melted particle resin is concentrated in the upper parts of
the yarns in the
elevated areas of yarns, under the surface itself.
[0025] In one embodiment, the textile fabric also includes a
barrier layer attached to
a bottom surface opposite the top surface and a macro-pattern embossed into
the textile
fabric. The macro-pattern includes raised areas of the textile fabric and
lowered areas of
the textile fabric. Adjacent raised areas and adjacent lowered areas are
spaced at intervals
wider than the spacing between adjacent elevated areas of yams and depressed
areas of
yarns. In addition, the lowered areas of the textile fabric have a lowered
area depth that is
deeper than a depressed area depth formed originally by the yarns. In one
embodiment,
the particles are present within the lowered areas of the textile fabric at a
higher
concentration than within the raised areas of the textile fabric, and the
melted particle resin
in the lowered areas of the textile fabric is located below a level of the
raised areas.
[0026] In one embodiment, the textile fabric is a nonwoven layer
formed with
filaments or staple fibers. In one embodiment, the textile fabric includes a
cushion layer
attached to the barrier layer. In one embodiment, the plurality of gaps has a
plurality of gap
widths. These plurality of gap widths include widths less than about 100
microns. In one
embodiment, the particles in the plurality of particles have a particle
diameter of from about
400 microns to about 700 microns. In one embodiment, the particles in the
plurality of
particles are dispersed at a weight of up to about 2.6 oz/yd2. The plurality
of particles
includes at least one of low-melting particles and non-melting particles
configured to impart
at least one of desired properties or visual effects to a top surface of the
textile fabric.
[0027] Exemplary embodiments are also directed to a method for
improving surface
and cut-edge stability of a textile fabric having a textured surface without
losing the fibrous
feel of the surface. A textile fabric having a plurality of yarns and a
plurality of gaps
disposed within the yarns is selected. The yarns loop into and out of the
textile fabric
forming a pattern of elevated areas of yarns and depressed areas of yams. The
yarns have
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a yarn melting point. A plurality of particles is dispersed on the textile
fabric. The particles
have a particle melting point lower than the yarn melting point. At least a
portion of the
plurality of particles are caused to enter the gaps within the elevated areas
of yarns on a
top surface of the fabric. The plurality of particles is melted in situ to
create melted particle
resin, and at least a portion of the filaments in the yarns within the
elevated areas are left
free of melted particle resin.
[0028] In one embodiment, a first plurality of particles on the
textile fabric is
dispersed at a first time, and a second plurality of particles is dispersed on
the textile fabric
at a second time. The first plurality of particles is separate from the second
plurality of
particles, and the first time and second time are discrete periods of time. In
one
embodiment, the plurality of particles is dispersed across the textile fabric
in accordance
with a predetermined pattern by sifting the plurality of particles onto a top
surface of the
textile fabric. In addition, at least one of applying vacuum to a bottom
surface of the textile
fabric opposite the top surface, vibrating the textile fabric, blowing air
onto the top surface,
sweeping the top surface, brushing the top surface, and cold pressing the
textile fabric is
performed to minimize particle exposure at the elevated areas of yarns and to
promote
particle concentration at the depressed areas of yarns.
[0029] In one embodiment, dispersing the plurality of particles
includes incorporating
the plurality of particles into a liquid suspension, applying the liquid
suspension to the top
surface of the textile fabric and evaporating liquid from the liquid
suspension after applying
the liquid suspension to the top surface. In one embodiment, the textile
fabric is embossed
prior to dispersing the plurality of particles with a macro pattern containing
raised areas of
the textile fabric and lowered areas of the textile fabric. The plurality of
particles is directed
to concentrate at the lowered areas using at least one of vacuum, brushing,
sweeping,
vibration and cold pressing. In one embodiment, a barrier layer is attached to
a bottom face
of the fabric opposite the top face. In one embodiment, a cushioning backing
layer is
attached to the barrier layer.
[0030] Exemplary embodiments are also directed to a method for
creating a liquid-
blocking three-dimensionally textured textile fabric with a highly durable and
fibrous textile
surface and non-fraying cut edges. A textile fabric having filaments on a top
surface and a
liquid blocking barrier attached to a bottom surface opposite the top surface
is embossed
using an embossing pattern that forms raised areas of fabric and lowered areas
of fabric on
the top surface. A plurality of particles is dispersed on the top surface, and
the particles
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deposited on the raised areas to are directed enter the gaps between the
filaments. The
particles disposed on the top surface move towards and into the lowered areas,
and heat is
applied to melt the particles in the gaps and the particles that moved into
the lowered
areas. A sufficient amount of particles are moved into the lowered areas that
melted
particle resin resulting from the particles in the lowered areas being melted
seals the
lowered areas and eliminates failure of the liquid blocking barrier due to the
embossing
action.
100311 In one embodiment, at least one of vacuum, brushing,
sweeping, vibration,
blown air and cold pressing is used to move the particles into the lowered
areas. In one
embodiment, a backing layer is attached to the barrier layer. In one
embodiment, at least
one of low-melting particles and non-melting particles selected to impart at
least one of
desired properties or visual effects to the top surface are dispersed on the
top surface.
[0032] In one embodiment, polymers are dissolved in suitable
chemicals and applied
to the surface of the various fabrics in amounts and viscosities confining the
penetration of
the dissolved polymer near the surface. Additional solvent is then applied to
the surface to
force part of or all the polymeric solution under the surface before applying
heat, forced air,
vacuum, or combinations thereof to evaporate the solvent and leave most of the
dissolved
polymer in a layer under the surface, maintaining the textile feel of the
surface.
[0033] In one embodiment, the liquid suspension or polymeric
solution is applied by
immersion, including partial immersion of the fabric and complete immersion of
the fabric to
reach the entire fabric. In one embodiment, immersion of the fabric is
followed by one or
more of squeezing or applying pressure to the fabric, applying vacuum to the
fabric or
directing forced air on the fabric to extract any extra liquid from the
fabric. In one
embodiment, additional liquid or solvent is applied to the surface of the
fabric before
applying heat to the fabric to drive the particles or the polymer solution
under the surface,
preserving the fibrous look and feel of the surface.
[0034] The use of a polymeric solution improves the ability to
reach the interstices
between fibers, fiber bundles or the spaces within and around yarns and yarn
bundles. In
addition, the viscosity of the polymeric solution can be adjusted by adjusting
the ratio of
polymer to solvent. Volatile solvents are selected to ensure evaporation
without residue to
avoid secondary problems such as soiling.
100351 Exemplary embodiments are directed to a method for
stabilizing a textile
fabric that suspends a plurality of polymeric particles in a liquid to create
a liquid
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suspension of polymeric particles and applies the liquid suspension of
polymeric particles
to the textile fabric. In one embodiment, a plurality of polyester,
polyethylene, polypropylene
polyurethane, polyvinyl acetate, polyvinyl alcohol, polyamide or acrylic
particles are
suspended in the liquid. In one embodiment, at least a portion of the
polymeric particles
have a chemical composition that is compatible with fibers in the textile
fabric to form
chemical bonds with the fibers. In one embodiment, at least a portion of the
polymeric
particles is ground recycled textile products containing powderized low melt
content.
Suitable liquids include water and water containing surfactants.
[0036] In one embodiment, the liquid suspension is applied by
immersing the textile
fabric in the liquid suspension. In one embodiment, the liquid suspension is
applied
uniformly to a top surface of the textile fabric. In one embodiment, an
initial volume of the
liquid suspension is applied to the top surface of the textile fabric. The
initial volume is
sufficient to penetrate from the top surface into the textile fabric with a
penetration depth
that is less than a thickness of the textile fabric.
[0037] An additional volume of the liquid is applied to a top
surface of the textile
fabric. The additional volume is sufficient to carry at least a portion of the
plurality of
polymeric particles into the textile fabric and away from the top surface. In
one
embodiment, the additional volume of the liquid is applied to the top surface
by wet
brushing the liquid onto the top surface, wet rolling the liquid onto the top
surface, spraying
the liquid onto the top surface, or combinations thereof. In one embodiment,
additives
having a melting point that is higher than the temperature applied to the
textile fabric are
incorporated into at least one of the liquid suspension of particles and the
additional volume
of liquid. The additives affect at least one of a color of the textile fabric,
an abrasiveness of
the textile fabric, an absorptiveness of the textile fabric and antimicrobial
properties of the
textile fabric. In one embodiment, a repellent is added into at least one of
the liquid
suspension of particles and the additional volume of liquid.
[0038] Heat is applied to the textile fabric. The applied heat is
sufficient to evaporate
the liquid applied to the textile fabric and to melt the plurality of polymer
particles in situ. In
one embodiment, a textile fabric containing a plurality of looping yams is
selected. The
plurality of looping yarns includes an upper portion adjacent the top surface.
In one
embodiment, the textile fabric is embossed with a coarse pattern containing
elevated areas
and depressed areas. The liquid suspension is applied only to the elevated
areas of the
textile fabric embossed with the coarse pattern. In one embodiment, the
textile fabric
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containing the melted polymeric particles is needled with smooth fine needles
to facilitate
water vapor penetration through the textile fabric.
[0039] Exemplary embodiments are also directed to a method for
stabilizing a textile
fabric that dissolves a polymer in a solvent to create a polymeric solution
and applies the
polymeric solution to the textile fabric. In one embodiment, polyesters,
polyurethanes,
polystyrenes, acrylics or polyamides are dissolved in the solvent. In one
embodiment, the
polymers are dissolved in a volatile organic solvent. In one embodiment, the
dissolved
polymer has a chemical composition that is compatible with fibers in the
textile fabric to
form chemical bonds with the fibers. In one embodiment, at least a portion of
dissolved
polymer is ground recycled textile products.
[0040] In one embodiment, an initial volume of the polymeric
solution is applied to
the top surface of the textile fabric. The initial volume is sufficient to
penetrate from the top
surface into the textile fabric a penetration depth that is less than a
thickness of the textile
fabric. In one embodiment, the polymeric solution is applied in a plurality of
discrete
applications. In one embodiment, a viscosity of the polymeric solution is
varied among the
plurality of discrete applications by varying a ratio of polymer to solvent in
the polymeric
solution. In one embodiment, the textile fabric blocks water and passes water
vapors.
[0041] An additional volume of the solvent is applied to a top
surface of the textile
fabric. The additional volume is sufficient to carry at least a portion of the
dissolved polymer
into the textile fabric and away from the top surface. In one embodiment,
additives having a
melting point that is greater than a temperature of the heat applied to the
textile fabric are
incorporated into at least one of the polymeric solution and the additional
volume of solvent.
The additives affect at least one of a color of the textile fabric, an
abrasiveness of the textile
fabric, an absorptiveness of the textile fabric and antimicrobial properties
of the textile
fabric. In one embodiment, a repellent is incorporated into at least one of
the polymeric
solution and the additional volume of solvent.
[0042] At least one or more of forced air, vacuum and heat is
applied to the textile
fabric to evaporate the solvent applied to the textile fabric and to set the
polymer in situ. In
one embodiment, a nonwoven textile fabric formed with filaments or staple
fibers or a textile
fabric containing a plurality of looping yams that form the top surface is
selected. In one
embodiment, a textile fabric containing a plurality of looping yarns is
selected. The plurality
of looping yams includes an upper portion adjacent the top surface. In one
embodiment,
the textile fabric is a stitchbonded fabric containing loops of yam that form
the top surface.
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In one embodiment, the textile fabric is embossed with a coarse pattern
containing elevated
areas and depressed areas. The polymeric solution is applied only to the
elevated areas of
the textile fabric embossed with the coarse pattern.
BRIEF DESCRIPTION OF THE DRAWINGS
[0043] The accompanying drawings, which are incorporated in and
constitute a part
of the specification, illustrate a plurality of embodiments and, together with
the following
descriptions, explain these embodiments.
[0044] Fig. 1 is a schematic representation of a top view of a
textile fabric with a
plurality of particles dispersed over the top surface.
[0045] Fig. 2 is a schematic representation of an embodiment of a
portion of a yarn
illustrating the filaments forming the yarn, the gaps among the filaments, and
the particles
deposited on the yams.
[0046] Fig. 3 is a schematic cross-sectional side view of the
fabric of Fig. 1;
[0047] Fig. 4 is a schematic representation of a side view of an
embodiment of a
textile fabric containing an arrangement of a plurality of particles;
[0048] Fig. 5 is the schematic representation of a cross-section of
an embodiment of
a textile fabric placed over a barrier layer, embossed with a macro pattern
and containing
an arrangement of a plurality of particles;
[0049] Fig. 6 is a schematic representation of a side view of an
embodiment of a
textile fabric integrated into a composite and containing an arrangement of a
plurality of
particles;
[0050] Fig. 7 is the schematic representation of a side view of an
embodiment of a
textile fabric integrated into a composite, embossed with a macro pattern and
containing an
arrangement of a plurality of particles;
[0051] Fig. 8 is a flow chart illustrating an embodiment of a
method for making a
textile fabric having an increase in surface and cut edge durability;
[0052] Fig. 9 is a flow chart illustrating another embodiment of a
method for making a
textile fabric having an increase in surface and cut edge durability; and
[0053] Fig. 10 is a schematic representation of a textile fabric
with polymer or
polymeric particles introduced as a solution or suspension.
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DETAILED DESCRIPTION
[0054] The following description of the embodiments refers to the
accompanying
figures. The same reference numbers in different figures identify the same or
similar
elements. Reference throughout the whole specification to "one embodiment" or
"an
embodiment" means that a particular feature, structure or characteristic
described in
connection with an embodiment is included in at least one embodiment of the
subject
matter disclosed. Thus, the appearance of the phrases "in one embodiment" or
"in an
embodiment" in various places throughout the specification is not necessarily
referring to
the same embodiment. Further, particular features, structures or
characteristics may be
combined in any suitable manner in one or more embodiments.
[0055] Exemplary embodiments are directed to incorporating low-
melting adhesive
particles or powders into the surface of a textile fabric. In one embodiment,
the particles are
deposited onto the top surface of the textile fabric by sifting. In another
embodiment, the
particles are applied to the top surface of the textile fabric or floor
covering as a suspension
in a fluid. Suitable fluids include, but at not limited to, water and water
containing
surfactants mixed in low percentage levels. In all embodiments, the textile
fabric or floor
covering has a three-dimensional surface. The three-dimensional surface of the
fabric
includes elevated areas of yarns and depressed areas of yarns. In one
embodiment, the
fabric is attached to a backing. In one embodiment, the particles descend into
the
interstices between and among the surface fibers. In one embodiment, the
particles
descend into the gaps between yams that form the surface of the fabric. In one
embodiment the particles also descend into the depressions or spaces that may
be formed
as the yarns are inter-looped along a generally flat surface.
[0056] The deposited particles are melted by raising the
temperature of the surface
of the fabric or of the entire fabric. In one embodiment, a fabric formed with
looping yarns
entering and exiting the surface is deeply embossed with patterns coarser than
the patterns
formed by the yarns. In one embodiment the depth of the embossed patterns
exceeds the
pre-embossed thickness of the fabric. The embossed patterns include raised
areas of fabric
and lowered areas of fabric. The particles, depending upon their size and
shape may
proceed by gravity predominantly into the lowered areas of fabric compared to
the particles
in the raised areas of fabric. As the deposited particles melt to form melted
particle resin,
the melted particle resin flows to fill-in the gaps and interstices and
increase resistance to
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fluid penetration in the lowered areas, which may have been previously thinned-
out or
perforated during embossing, lowering resistance to fluid penetration.
[0057] Depending upon the structure of the top surface of the
fabric, the nature of
the surface fibers or yarns, the amount of deposited particles, the melt
characteristics of the
particles, and the structure of the deposited particles, different advantages
and
improvements in different embodiments are achieved in the textile fabric.
These
advantages and improvements include, but are not limited to, simple
stabilization of the
elevated areas of yarns and raised areas of fabric versus wear and abrasion,
achieving a
breathable fluid barrier with minimum hardening of the textile fabric surface,
and blocking of
fluid penetration through the textile fabric without excessive hardening and
without
eliminating the fibrous feel of the top surface.
[0058] Referring initially to Fig. 1, exemplary embodiments are
directed to a textile
fabric 100 containing a plurality of yarns 102. As illustrated, the yams are
arranged as a
knit textile fabric. However, the yarns can also form other types of textile
fabrics including,
for example, woven fabrics, stitchbonded textile fabrics and tufted textile
fabrics. In general,
the yarns have a yam melting point. Each yam is constructed from and contains
a plurality
of distinct filaments or individual fibers 104.
[0059] The textile fabric includes a plurality of gaps disposed
within and among the
yarns. These gaps in the plurality of gaps include spacings 106 between yarns
in the
plurality of yarns. The size and shape of the individual spacings varies.
[0060] These gaps also include openings 108 between individual
filaments within
each yarn. The size and shape of the individual openings vary between
different pairs of
filaments and along the length of filaments as the filaments are twisted and
entangled. In
general, each gap has a gap width. Therefore, the plurality of gaps represents
a plurality of
gap widths. Each opening within the yarns has an opening gap width, and each
spacing
between yams has a spacing gap width, which includes larger spacing gap widths
and
smaller spacing gap widths. The size of the gap width can vary along the
length of the gap.
In one embodiment, an individual gap width is the largest measured distance
across the
gap. As used herein, the gap width refers to a size or dimension of a largest
object or
particle that can pass through the gap. Suitable dimensions include the
diameter of a
sphere or the diagonal of a cube. The gap widths associated with the openings
between
filaments are smaller than the gap widths associated with the spacings between
yarns. In
one embodiment, the plurality of gap widths includes widths less than about
500 microns.
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In one embodiment, the plurality of gap widths includes widths of from about
400 microns to
about 500 microns. In one embodiment, the plurality of gap widths includes
widths less
than about 100 microns.
[0061] The textile fabric includes a plurality of particles 105
dispersed across the
textile fabric within the yarns. In one embodiment, the particles in the
plurality of particles
include particles have the same size and shape. In another embodiment, the
particles in
the plurality of particles include particles that vary in at least one of size
and shape. As
illustrated, the particles may include spherical particles. These spherical
particles can
include small particles that are smaller than the gap width of all of the
spacings in the textile
fabric, medium particles that are smaller than the gap width of some of the
openings but
larger than the gap width of other openings, and large particles that are
larger than the gap
width of all openings. The particles will pass into the gaps having a gap
width larger than
the particles. The large particles will remain on the top surface of the
textile fabric. In one
embodiment, a portion of the small and medium particles remain on the top
surface of the
textile fabric and do not pass into the openings. In addition to spherical
particles, suitable
particles include particles having other shapes including, for example, cubic
particles and
non-uniformly shaped particles.
[0062] Referring to Fig. 2, the size and shape of the particles are
also selected
based on the gap widths of the openings between filaments in the individual
yarns. In one
embodiment, the plurality of particles includes a first size of particles 130
that are small
enough to pass through or to penetrate the openings between filaments. In one
embodiment, the plurality of particles includes a second size of particles 132
larger than the
first size of particles that may penetrate the spacings between yarns but is
too large to pass
through the openings between filaments. In one embodiment, the textile fabric
includes
both the first size and the second size of particles.
[0063] The particles within the plurality of particles are
dispersed in at least one of
the openings between filaments and the spacings between yarns. In one
embodiment, the
plurality of particles includes particles having a size smaller than at least
one gap width in
the plurality of gap widths. In one embodiment, the particles in the plurality
of particles have
a nominal particle size of about 82 microns. In one embodiment, the particles
in the plurality
of particles have a particle size of about 400 microns to about 700 microns.
[0064] Suitable materials for the particles include, but are not
limited to, plastics and
polymers. In one embodiment, the particles include at least one of polyester
particles and
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polyethylene particles. In one embodiment, the particles are formed from a
material or
materials having a particle melting point temperature lower than the melting
point of the
fibers within the yarns. Therefore, the particles can be subjected to heat and
melted without
melting the yarns.
[0065] Returning to Fig. 1, the arrangement, distribution and
density of particles is
shown for illustrative purposes. The particles in the plurality of particles
are introduced onto
a top surface of the textile fabric in accordance with a predetermined density
and
distribution of particles. Therefore, the textile fabric can include areas of
overlapping or
stacked particles and areas containing few if any particles. In one embodiment
at least one
of a pre-determined distribution of the plurality of particles across the
textile fabric and a
depth of penetration of particles in the plurality of particles into from the
top surface through
the gaps and into the fabric are established. The textile fabric has upper
strata, i.e., the
portion of the textile fabric adjacent the top surface, and in one embodiment,
a desired
depth of penetration is established such that a majority of the plurality of
particles are
located within the upper strata. Suitable methods for establishing the desired
distribution of
particles include, but are not limited to, sifting the plurality of particles
onto the top surface
and applying the particles in the liquid suspension. In one embodiment, the
particles in the
plurality of particles are dispersed within the yarns at a weight of up to
about 2.6 oz/yd2.
[0066] Referring now to Fig. 3, the yarns in the plurality of yams
form a textured
surface pattern that creates elevated areas of yarns 134 and depressed areas
of yarns136.
A given yarn following the textured surface pattem can transition from an
elevated area of
yarn to a depressed area of yam across the surface of the textile fabric. In
one
embodiment, the desired pattern of distribution of particles is varied in
accordance with the
location of the elevated areas of yarns and depressed areas of yarns. In one
embodiment,
the particles in the plurality of particles have a particle size greater than
a size of the gaps
among the plurality of surface fibers in the elevated areas. In one
embodiment, the particles
in the plurality of particles include larger particles and smaller particles.
Most of the smaller
particles pass into the gaps among the surface fibers. The remainder of the
particles,
including the larger particles, fall into or are guided into the depressed
areas of yarns using,
for example, vacuum, blown air, vibration, surface brushing, or a combination
of two or
more of these guiding methods.
[0067] The particles in the plurality of particles are introduced
or applied to the top
surface 140 of the textile fabric, for example, using sifting or application
in a liquid
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suspension. In one embodiment, both the desired pattern of particles and the
desired depth
of penetration can be adjusted using vacuum that is applied to a bottom
surface 142 of the
textile fabric opposite the top surface 140. In one embodiment, vacuum is
applied to the
bottom surface simultaneously with introduction of the plurality of particles
onto the top
surface. Other techniques of distributing particles across and within the
textile fabric can
also be used either alone or in combination with the application of vacuum. In
one
embodiment, the fabric is vibrated to control the depth of penetration of the
plurality of
particles.
[0068] In one embodiment, the textile fabric also includes a water-
repellent coating.
In one embodiment, the water-repellent coating is applied and cured to the
textile fabric
before the plurality of particles is introduced onto the top surface.
Alternatively, the water-
repellent coating is applied after the plurality of particles is introduced
onto the top surface
and cured as the particles are melted with heat.
[0069] The applied particles are contained within the textile
fabric as discrete
particles. In addition, particles that are larger than the gap widths remain
on the top surface
of the textile fabric. In order to incorporate the particles into the textile
fabric, the particles in
the plurality of particles are melted using applied heat. Suitable methods for
applying heat
to a textile fabric are known and available in the art and include using
radiation, hot air or a
heated surface in light contact with the elevated areas of the top surface.
[0070] In one embodiment, the textile fabric is cooled following
heating to melt the
plurality of particles. After heating and cooling, at least a portion of the
plurality of surface
yarns or filaments within the surface yarns within elevated areas of yarns of
the textile
fabric are free of melted particles. Applying heat to melt the plurality of
particles improves at
least one of overall durability, fluid penetration resistance and cut-edge
fraying resistance
of the fabric. In one embodiment, vacuum is applied to the bottom surface of
the fabric
while applying heat to the top surface to melt the plurality of particles.
[0071] Referring now to Fig. 4, an embodiment of the textile fabric
200 is illustrated.
As illustrated, the textile fabric includes a plurality of yarns 202 looping
in and out of the top
surface 240 and the bottom surface 242 of the textile fabric with a given
repeating interval
235. In one embodiment, the yarns are bulked and gaps among the yarn-forming
filaments
or fibers are present. The plurality of yarns in the textile fabric form a
textured surface
pattern of elevated areas of yams 234, wherein the bulked yarns remain bulked
and the
gaps between filaments or fibers remain open, and depressed areas of yarns
236, wherein
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the inter-looped yarns are compressed and the gaps widths among filaments or
fibers is
reduced. When cut to size, the yarn ends at the cut edges 207 are vulnerable
to fray and
"fuzz".
[0072] Particles ranging from particles 218 that are smaller than
the gap widths
among the fibers or filaments of the yams, to particles 219 that are larger
are applied to the
top surface of the fabric. Application of the particles is followed by the
application of heat at
a temperature above the melting point of the particles but below the melting
point of the
fibers or filaments in the yarns. Within the elevated areas of yarns most of
the particles 218
proceed into the surface gaps and are located under the exposed surface of the
yarns,
leaving the fibers or filaments forming the yarns mostly exposed. Within the
depressed
areas of yarns the particles tend to accumulate towards the center of the
depressed areas.
Most of the large or small particles remaining over the elevated areas can be
propelled into
the depressed areas using vacuum, vibration or brushing applied either
simultaneously or
sequentially.
[0073] After heat is applied to melt the particles the melted
particle resin at the
elevated areas of yarns, including the majority of melted particle resin
located within the
yarns and the small amount of melted particle resin located at or near the top
surface
improve surface abrasion resistance and edge fraying resistance The melted
particle resin
and solid particles within the depressed areas of yams may remain on the top
surface
without affecting the fibrous feel of the fabric as melted particle resin and
solid particles on
the top surface are located below and surrounded by the elevated areas of
yarns. In
summary, applying heat toward the top surface melts the particles to produce
melted
particle resin which flows 22 in the molten state and bond the fibers and
filaments within the
yarns and adjacent yarns to each other. This bonding with melted particle
resin stabilizes
the textile fabric top surface and the cut edges while leaving the top surface
with a textured
and textile feel.
[0074] Referring now to Fig. 5, in one embodiment, the textile
fabric 200 is combined
with a barrier layer 201 and embossed with a coarser and deeper "macro
pattern", creating
new raised areas of fabric 250 and lowered areas of fabric 252. The new
elevated areas
and depressed areas define a three-dimensional surface. In one embodiment, the
textile
fabric and barrier layer are combined and subsequently embossed. A heated
embossing
tool (not shown) with projections deeper than the original thickness of the
textile fabric and
arranged with a spacing wider than the spacing between elevated areas of yarns
and
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depressed areas of yams presses the textile fabric and barrier layer into a
soft and resilient
back-up plate or roll 299, for example, silicon rubber. The silicon rubber
surface conforms,
withstands high temperatures and releases any resin that penetrates through at
the highly
deformed lowered areas. As a result of the deep embossing the depth of the
embossed
fabric exceeds the thickness of the original fabric. The barrier layer is
usually maintained in
the raised areas, which have been subjected to negligible deformation, and
compromised
in the lowered areas, which have been highly deformed by the projections of
the embossing
tool.
[0075] A plurality of particles ranging in size from smaller than
the gap widths on the
top surface of the yarns to larger than the gap widths on the top surface of
the yarns are
applied to the top surface of the textile fabric. These different size
particles can be applied
separately or simultaneously. Suitable methods for applying the particles
include sifting. In
one embodiment, particles 218, which are smaller than the gaps among the
filaments or
fibers within the yarns penetrate the yarns. Particles 219 that are larger
tend to descend
down into the bottom of the lowered areas of the textile fabric by simple
gravity. The larger
particles, as well as any smaller particles that may be located at the
elevated areas may be
aided to move into the compromised lowered areas by applying vacuum under the
fabric,
vibrating the fabric, blowing air onto the fabric, or any combination of these
techniques,
applied separately or simultaneously. When the accumulated particles in the
lowered
areas melt, the melted particle resin fills and seals openings created in the
barrier by
embossing. In one embodiment, the melted particle resin in the lowered areas
protrudes
locally over the fibers or filaments of the yarns without affecting surface
tactility in the textile
fabric as the melted particle resin remains below the yarn surface in the
raised areas.
[0076] In one embodiment, at least parts of the fibers or filaments
in the raised areas
are exposed and are free of melted particle resin after heat is applied to
melt the particles.
As heat applied toward the top surface melts the smaller particles, allowing
the molten
particles 220 to flow into the yarns, the top surface of the textile fabric
and the cut edges
are stabilized while retaining the fibrous feel of the top surface. The
melting temperatures of
the smaller particles and larger particles may be the same or different, and
heat may be
applied to melt both simultaneously or separately. In addition, heat may be
applied to melt
the particles gradually.
[0077] In other embodiments, the textile fabric illustrated in Fig.
5 is any fabric,
woven, knit, stitchbonded or nonwoven, built with or without yarns, using
filaments or staple
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fibers. In other embodiments, the textile fabric includes pre-shaped micro
patterns
exhibiting elevated and depressed areas. In one embodiment, the textile fabric
is initially
flat without any elevated or depressed areas of yarns. In one embodiment, the
textile fabric
is pre-treated with repellent solutions. In one embodiment, the textile fabric
is treated with
solutions containing particles of a smaller size than the openings among
surface fibers or
filaments. If the textile fabric is embossed with a barrier attached to the
bottom surface,
particles applied to the top surface that remain above the yarns, fibers or
filaments at the
elevated areas of yarns or raised areas of the textile fabric can be directed
to the
depressed areas of yams or lowered areas of the textile fabric where the
barrier may be
compromised by the embossing action to restore the barrier and to stabilize
the fabric.
[0078] Referring to Figs. 6 and 7, in one embodiment, a textile
fabric 501 is
incorporated into a composite 500. As shown in Fig. 6, the textile fabric 501
is placed over
or pre-attached to a barrier layer 505 followed by placement over a cushioning
layer 510.
The cushioning layer eliminates the need for the soft silicon rubber that is
used to form the
embossed fabric of Fig. 5 and is attached permanently to the barrier and the
fabric after
being embossed with heat as shown in Fig. 7. As shown in Fig. 6, the textile
fabric, in a
similar manner to the fabric of Fig. 4, includes a plurality of yarns 502
looping in and out of
the top surface 540 and the bottom surface 542 of the textile fabric forming
the textured
surface pattern of elevated areas of yarns 534 and depressed areas yams 536
with a given
repeating interval 535. When cut to size, the textile fabric in the composite
includes cut
edges 507.
[0079] As in the sequence described in relation to Figs. 4 and 5, a
plurality of low-
melting particles is deposited onto the textile fabric in the composite of
Fig. 6, for example,
by sifting. The particles can be added in a single application or in multiple
applications. In
one embodiment, at least some of the particles penetrate the gaps between the
yarns or
filaments. Subsequently applied heat melts the particles 520 that migrate into
the yarns and
into the depressed areas of the yarns of the fabric, away from the top
surface, stabilizing
the surface without losing the textile feel of the surface.
[0080] Referring to Fig. 7, with or without the pre-application of
particles to the face
fabric, and with or without preheating the face fabric to melt such particles,
if any, the layers
of Fig. 6 are embossed with a macro pattern and laminated with heat,
integrating the three
layers and producing the composite 500 illustrated in Fig. 7. The macro
pattern creates
raised areas 515 and lowered areas 516 repeating with a given spacing 517. The
particles
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and resin deposited onto the elevated areas and the melted particle resin that
migrates into
the textile fabric, if any, stabilize the top surface and the cut edges of the
composite. The
barrier layer is subject to compromise at the bottom of the lowered areas
where the
projections of the embossing tool force the fibers and the barrier layer open.
[0081] The barrier layer is usually maintained in the embossed
raised areas but may
be compromised in the embossed lowered areas. A plurality of low-melting
particles is
introduced onto the top surface 540 of the fabric layer in one or more
applications, in a
manner as depicted, for example, in Fig. 5. The particles in the plurality of
particles can all
be the same size or can have a plurality of different sizes. As was discussed
above with
regards to Fig. 5, the particles in the lowered areas tend to descend into the
lowered areas
and accumulate near the compromised barrier bottom by simple gravity as these
particles
do not enter the smaller gaps between the fibers or filament within the raised
areas.
Vibration or blown air, preferably combined with vacuum applied underneath
through the
backing layer in cases wherein the backing layer is air-permeable, is used to
promote the
concentration of particles at the lowered areas and to minimize or eliminate
particles within
the raised areas. After subsequent heat treatment, the compromised barrier at
the bottom
of the lowered areas is restored, and some degree of extra stability is added
to the entire
surface with limited frequency of melted particles on the surface.
[0082] The process used in Figs. 6 and 7 can be applied to any
surface fabric
attached to a barrier layer. The surface fabric may be formed with individual
fibers or
filaments instead of yarns, may be initially flat and non-textured and may or
may not be pre-
treated with fine particles entering between surface filaments or fibers.
After embossing
with a deep pattern, particles coarser or finer than the gap widths among the
surface fibers
or filaments that remain on the top surface at the raised areas of the textile
fabric are
directed to the lowered areas with vacuum, blown air, vibration, sweeping by
brushing or
combinations of these techniques. This relieves the raised areas of fabric
from
unnecessary surface resin while reinforcing the barrier within the depressed
areas.
[0083] Referring now to Fig. 8, exemplary embodiments are directed
to a method for
improving surface and edge durability and resistance to fluid penetration in a
textile fabric
400. Initially, the desired textile fabric is selected 402. Suitable textile
fabrics include, but
are not limited to knit fabrics, woven fabrics, tufted fabrics, nonwoven
fabrics and
stitchbonded fabrics. The textile fabric is formed from a plurality of yarns
or filaments or
staple fibers and contains a plurality of gaps disposed among the filaments or
fibers. The
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yarns, filaments or fibers have a yarn melting point. In one embodiment, the
yarns filament
or fibers form a textured surface pattern with elevated areas of yarns and
depressed areas
of yams. The gaps define a plurality of gap widths
[0084] A determination is then made regarding whether the textile
fabric is to be
combined with a barrier layer to form a composite 404. If the textile fabric
is to be
incorporated into a composite, for example, with barrier properties, the
additional barrier
layer is added to the textile fabric 406. If the textile fabric is not to be
combined with a
barrier layer, a determination is made regarding whether the textile fabric is
to be combined
with a backing layer 408, for example, a cushioning layer. If the textile
fabric is to be
combined with the backing layer, the backing layer is added and attached to
the textile
fabric 410.
[0085] A determination is then made regarding the type and
composition of the
particles to be added, the size or sizes of the particles to be added, the
melting temperature
of each type of particle, the melt viscosity or melt index of each type of
particle, and the
distribution pattern of the particles to be attained across the top surface of
the textile fabric
412. In one embodiment, the particles for the plurality of particles are
selected having a
particle size less than a first gap width or a second gap width to disperse
particles in at
least one of the openings between filaments and the spacings between yams.
Having
identified the particles to be applied, a determination is then made regarding
the number of
applications 414 and the type of applications 416. Suitable types of
applications include
sifting and applying in a liquid suspension.
[0086] A determination is then made regarding whether the textile
fabric or
composite is to be embossed with a macro pattern 418. If the pattern is to be
embossed,
the textile fabric or composite is embossed with a macro pattern containing
raised areas
and lowered areas 420.
[0087] Following embossing with the macro pattern or if the textile
fabric is not to be
embossed, the selected plurality of particles is dispersed on the textile
fabric 422. The
particles are dispersed in accordance with the type of particles selected, the
type of
application, the number of applications and the desired distribution of
particles. In one
embodiment, at least one of dry sweeping or brushing, vacuum, vibration, or
blown air is
applied to the textile fabric to direct particles that fail to enter the gaps
between the surface
filaments or fibers at the raised areas into the lowered areas. In one
embodiment, the
plurality of particles includes particles having a size smaller than at least
one gap width in
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the plurality of gap widths and a particle melting point temperature lower
than the yarn
melting point. In one embodiment, dispersing the plurality of particles
comprises sifting the
plurality of particles onto a top surface of the textile fabric. In one
embodiment, dispersing
the plurality of particles includes incorporating the plurality of particles
into a liquid
suspension, applying the liquid suspension to a top surface of the textile
fabric and
evaporating a liquid from the liquid suspension after applying the liquid
suspension to the
top surface, and optionally wiping the surface with a wet or dry tool to cause
the particles to
proceed between the surface fibers or filaments and away from the surface.
[0088] After the particles are dispersed on the textile fabric and
directed to the
desired locations, a determination is made regarding how heat is going to be
applied to
melt the particles and to disperse the resulting melted particle resin through
the textile
fabric and yarns 424. Sufficient heat is applied to the textile fabric to melt
particles 426
within the plurality of particles dispersed within the yams. In one
embodiment, applying
heat to the textile fabric includes using at least one of radiant heating,
convection and
conduction on a top surface of the textile fabric.
[0089] Referring to Fig. 9, exemplary embodiments are also directed
to a method for
making a fabric having increased resistance to one or more of surface wear,
edge fraying
or fluid penetration. A plurality of low-melting particles is introduced onto
a top surface of a
textile fabric 602. The top surface includes a plurality of surface fibers and
gaps among the
plurality the plurality of surface fibers. In one embodiment, the elevated
areas and
depressed areas define a three-dimensional surface. In one embodiment, the
surface fibers
are yarns, and the elevated and depressed yarns are defined by the looping of
the yarns
emerging from and returning into the fabric face. In one embodiment the
textile fabric is
generally flat, and the surface texture is formed exclusively with yarn loops.
[0090] In one embodiment, the plurality of low-melting particles is
introduced onto
the top surface includes sifting the plurality of particles into the top
surface of the fabric, for
example as a dry powder. In another embodiment, the plurality of low-melting
particles is
incorporated into a liquid suspension, e.g., water with or with a surfactant.
The liquid
suspension is applied to the top surface of the fabric. In one embodiment, the
liquid
suspension is applied only to the elevated areas of the top surface. In one
embodiment, the
method includes an evaporative heating step to evaporate the liquid from the
liquid
suspension following application of the liquid suspension to the top surface
and before
applying heat sufficient to melt the plurality of particles.
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[0091] In one embodiment, the plurality of low-melting particles
descends
disproportionately on the depressed areas rather than the elevated areas when
introducing
the plurality of low-melting particles onto the top surface. In one
embodiment, the particles
or powder has a particle size greater than a size of the gaps among the
plurality of surface
fibers in the elevated areas. In addition, a majority of the plurality of
particles are located in
the depressed areas. In one embodiment, the plurality of particles includes
larger particles
and smaller particles. The smaller particles pass into the gaps among the
surface fibers,
and the larger particles collect in the depressed areas. In one embodiment,
the plurality of
particles or powder is sifted to separate larger particles from the smaller
particles.
[0092] A desired planar pattern of particle distribution and depth
of penetration from
the top surface of the plurality of low-melt particles into the gaps is
established 604. In one
embodiment, the textile fabric includes upper strata, and establishing the
desired depth of
penetration is established such that a majority of the plurality of particles
or powder are
located within the upper strata. In one embodiment, a vacuum is applied to a
bottom
surface of the fabric opposite the top surface to control the planar
distribution of the plurality
of particles and the depth of penetration of the plurality of particles into
the fabric. In one
embodiment, vacuum is applied to the bottom surface while introducing the
plurality of low-
melting particles onto the top surface. In one embodiment, the fabric is
vibrated to control
the planar distribution and depth of penetration of the plurality of particles
either with or
without the simultaneous application of vacuum.
[0093] Heat is then applied to the top surface to melt the
plurality of particles or
powder 606. The method of applying the heat, the conditions during heating,
e.g., vacuum
and vibration, the type of particles, the embossed pattern on the fabric, can
affect the
location and flow of the molten resin during heating. In one embodiment, at
least a portion
of the plurality of surface fibers are free of melted particle resin. The
portion of the plurality
of surface fibers free of melted particle resin is located in the elevated
areas of the flat
fabric or the raised areas of the embossed pattern of the fabric either alone
or as part of a
composite.
[0094] In one embodiment, application of heat to melt the plurality
of particles
improves at least one of overall durability, fluid penetration resistance and
cut-edge fraying
resistance of the fabric. Suitable methods for applying heat include, but are
not limited to,
using radiation, hot air or a heated surface in light contact with the
elevated areas of the top
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surface. In one embodiment. vacuum is applied to a bottom surface of the
fabric opposite
the top surface while applying heat to the top surface to melt the plurality
of particles.
[0095] In one embodiment, the textile fabric is incorporated into a
composite and the
particles and heating applied to the composite. In one embodiment, a water-
repellent
coating is applied to the textile fabric. In one embodiment, the water-
repellent coating is
applied before introducing the plurality of low-melting particles onto the top
surface. In
another embodiment, the water-repellent coating is applied after introducing
the plurality of
low-melting particles onto the top surface. In addition to a single
application of particles
onto the top surface of the textile fabric, two or more applications of
particles or powders
can be used. For example, a first application can be made with a first size or
coarseness of
particles and a second application with a second size or coarseness of
particles. In one
embodiment, two applications are made using the same size or coarseness of
particles. In
one embodiment, a first application of particles is made to the textile
fabric, and a second
application of particles are made following embossing of the textile fabric
containing the first
application of particles.
[0096] In one embodiment, a barrier layer is located within the
lower strata of the
fabric or attached to a bottom surface of the fabric opposite the top surface.
The fabric is
embossed to create embossed raised areas and embossed lowered areas. The
barrier
layer is maintained in the embossed raised areas and compromised in the
embossed
lowered areas. Therefore, the textile fabric itself and the embossed pattern
can each
include raised areas and lowered areas. A plurality of low-melting particles
is introduced
onto the embossed lowered areas. This can be the first or second application
of particles. If
it is the second application of particles, the first application of particles
is made to the textile
fabric or composite containing the textile fabric prior to embossing. Heat is
applied to the
top surface to melt the plurality of particles and restore the barrier layer
in the embossed
lowered areas.
[0097] In one embodiment, a barrier layer is located within the
lower strata of the
textile fabric or attached to the bottom surface of the textile fabric
opposite the top surface,
and additionally the textile fabric containing the barrier layer is
incorporated into an upper
surface of a composite. The composite is embossed to create the embossed
raised areas
and embossed lowered areas. The barrier layer is maintained in the embossed
raised
areas and compromised in the embossed lowered areas. A plurality of low-
melting particles
is introduced onto the embossed lowered areas. This can be the first or second
application
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of particles. If it is the second application of particles, the first
application of particles was
made to the textile fabric or composite containing the textile fabric prior to
embossing. Heat
is applied to the top surface to melt the plurality of particles and to
restore the barrier layer
in the embossed lowered areas.
[0098] Embodiments involving the use of dissolved polymers applied
to the surface
or to the entire fabric and subsequently driven down into the fabric layers
under the surface
before applying heat can take advantage of many of the secondary treatments
available to
the embodiments involving powder application. These embodiments include the
addition of
active non-dissolving particles that are mixed with the dissolved polymer in
powder form,
barrier layers introduced under the textile fabric or within a composite
topped by the textile
fabric, fine and smooth needling applied to adjust the fluid blocking
properties after solvent
flash-off and curing, and multiple applications of the same polymeric solution
or different
polymeric solutions with or without intermediate surface treatment involving
extra solvent,
and with or without intermediate heat setting_
[0099] In one embodiment, a polymer solution with a relatively high
viscosity is first
applied to the textile fabric and forced into the lower strata of the fabric.
The solvent is then
evaporated, creating a relatively porous internal sublayer. In one embodiment,
the polymer
solution is heat-treated at this stage. Alternatively, the polymer solution is
left in place. A
second application of a less viscous polymeric solution seals the first
sublayer partially or
totally, creating a submerged fluid or gas barrier that can be engineered for
special effects
such as fluid blockage with or without vapor permeability. The viscosities of
each
application may be adjusted by adjusting the ratio of polymer to solvent and
can be tailored
to the particular type of textile fabric
[00100] In one embodiment, the chemical composition of the suspended
adhesive
particles or the chemical composition of the dissolved polymers is compatible
with the
fibers or yarns in the fabric. Chemical composition compatibility facilitates
the formation of
chemical bonds in addition to mechanical bonds by simply surrounding the
fibers, yarns or
fiber bundles of yams. In one embodiment, the particles or dissolved polymers
are either
partially or totally incompatible in chemical composition with the fibers or
yarns, but still
convenient to form bonded layers using heavier weights at a more conveniently
lower cost,
as in the case of ground recycled textiles.
[00101] In one embodiment, the suspended particles or polymeric
solution is applied
to the fabric using two or more discrete applications. Multiple applications
are used to
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achieve a desired balance of bulk, durability, edge stability, and planar
stiffness in the
fabric. In one embodiment, the type particles, the chemical compatibility of
the of the
particles, the use of additional fluid or solvent, and the form of the
particles, i.e., suspension
versus solution, are varied from application to application. For example, a
first application
utilizes polymers that are incompatible with some or all of the fibers in the
fabric. The first
application is followed by the application of additional fluid to drive the
polymer under the
surface of the fabric. A second application is then made with a polymer that
is chemically
compatible with the fibers. The second application is also followed by the
application of
additional fluid to drive the polymer under the surface of the fabric. The
resulting fabric has
a lower strata stabilized with mechanical bonds and an upper strata under the
surface
stabilized with both mechanical and chemical bonds.
EXAMPLES
[00102] In a first example, a textile fabric as illustrated in Fig.
4 was selected and
included a plurality of yarns forming a flat structure having a textured
surface pattern with a
given repeating interval. The surface pattern included a plurality of
protruding elevated yarn
areas and a plurality of depressed yarn areas. The yarns were bulked with gaps
open
between the filaments in the yarns. The surface gaps varied up to
approximately 0.004
inches or 100 microns. The textile fabric had a weight of 12 oz./sq. yd. (420
grams/sq. m)
and a thickness of 0.09 inches (2.25 mm). The textile fabric was treated with
a water
repellent treatment.
[00103] Low melt polyester particles with a nominal particle
diameter of 82 microns
were sifted onto the top surface 109 of the textile fabric at a weight
totaling approximately
1.0 oz. per sq. yd. The particles landed on the elevated yarn areas with some
direct
penetration between the surface fibers. Radiant heat was applied on the top
surface to melt
the applied particles throughout the fabric. Surface abrasion resistance and
cut-edge
fraying or fuzzing resistance improved dramatically. The elevated yarn areas
remained
fibrous. The top surface remained soft and textile like. Air and water vapor
permeability
were not noticeably affected. Liquid penetration resistance improved, and
spills remained
on the top surface for periods varying between several minutes and several
hours
[00104] In a second example using the same textile fabric as in Fig.
4, the 82 micron
particles were dispersed in water containing a surfactant. The dispersion was
applied
gently over the top surface of the fabric, touching only the elevated areas.
The particles
penetrated between filaments. The fabric was dried, and the particles were
activated with
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heat. Particle pick-up was approximately 0.6 oz./sq. yd. The thickness of the
fabric did not
change. The surface stability and cut edge fraying resistance were
satisfactory and
equivalent to the textile fabric as in the first example in which dry
particles were applied
using sifting. Air and water vapor permeability and resistance to spills were
not noticeably
different from the textile fabric without the dispersed particles.
[00105] In a third example, coarse particles having a particle size
varying between
approximately 400 and 700 microns were sifted over the top surface of the
textile fabric to
add approximately 0.35 oz./sq. yd. of weight. The particles were chosen to
have a high melt
index in order to flow freely when heated and molten without requiring
significant pressure.
Particles landed essentially equally onto the elevated areas and the depressed
areas. The
resin in the particles was activated by lightly touching the surface with a
"non-stick" hot iron.
Sufficient melted particle resin was found to be present on the elevated areas
to resist
fraying or fuzzing at the cut edges. The melted particle resin in the
depressed areas of
yarns also melted due to radiation from the heated iron; however, that melted
particle resin
remained in place without substantial penetration. The thickness of the fabric
remained at
the original 0.090 inches. Resistance to air, water vapor or spilled liquids
remained the
same as textile fabric without particles.
[00106] In a fourth example, the textile fabric was subjected to
vacuum applied to a
bottom surface opposite the top surface of the fabric. The vacuum was applied
as fine 82
micron particles were sifted onto the top surface. The distribution of
particles or powder
shifted toward the elevated areas, allowing air to pass through more freely as
compared to
the denser depressed areas. No significant effect on liquid penetration
resistance was
observed until added particle or powder weight was increased to approximately
2.6 oz./sq.
yd. (86 gm/sq. m). Following activation of the applied particles or powder
with radiant heat,
surface stability and edge fraying resistance improved further, while
considerable textile
feel on the surface remained. Liquid penetration resistance increased, with
the textile fabric
passing the 24 hr British Spill Test. However, water collected on the surface
could still be
forced-in by rubbing or by applying a pressure of approximately 20 psi to
simulate the
pressure of stepping onto collected puddles.
[00107] In a fifth example, the face or top surface of the textile
fabric of Fig. 4 was
converted to a liquid blocking layer by adding a second separate application
of fine
particles applied as a fine sifted powder. The fabric in the embodiment of the
fourth
example described above was subjected to a second sifting of fine 82 micron
particles or
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powder with simultaneous vacuum and planar vibration during the second powder
deposition. In addition, vacuum was applied to the bottom face of the fabric
as the fabric
was being subjected to heat. The 1.0 oz./sq. yd. of particles or powder
applied during the
second deposition by sifting brought the fabric weight up to 15.6 oz./sq. yd.
After activation
of the second application of particles or powder with radiant heat, the cut
edges were highly
stabilized. Air and water penetration resistance increased dramatically. Soapy
water failed
to penetrate the surface when puddles are brushed, rubbed or pressed. The
surface
maintained a semi fibrous fabric feel, with sporadic yarn/filament sections
protruding
beyond molten polymer.
[00108] In a sixth example, the textile fabric of Fig. 4 was placed
over a solid low-melt
barrier layer supported by a silicon rubber sheet, as shown in Figure 5.
Pressure and heat
were applied with a three-dimensional tool from the top surface of the fabric.
The result was
the three-dimensional textile fabric illustrated in Fig. 5. The resulting deep
embossed
macro pattern included deeper and coarser raised areas and lowered areas that
repeated
with a given spacing. The low melt resin backing layer melted at the compacted
lowered
areas and penetrated into the textile fabric, developing local barrier
failure. Approximately
0.5 oz./sq. yd. of coarse 400-700 micron particles or powder with a very high
melt index
were then sifted onto the embossed surface and radiant heat was applied to the
surface to
melt the deposited particles. The effect of melted particle resin on the
surface yarns within
the raised areas was similar to that within the elevated areas in the fabric
above before
embossing, with melted particle resin intermittent along the surface yarns at
the raised
areas. The barrier layer still developed leaks at the lowest parts of the
lowered areas, which
caused the fabric to lose effectiveness as a barrier to liquids. However, the
surface yams at
the cut edges were stabilized and resistant to fraying, while the surface
maintained a
fibrous feel, with surface filament segments within raised areas free of
resin.
[00109] In a seventh example spill resistance was restored to the
pre-embossed
three-dimensional textile fabric of the sixth example using a second
application of coarse
400-700 micron high-melt-index polyethylene powder or particles in addition to
the first
application performed on the textile fabric. The second application of
particles was
performed by sifting with vacuum simultaneously applied to the bottom surface
to add 2_0
oz./sq. yd., bringing the total weight to 14.5 oz./sq. yd. The particles or
powder guided by
the preferential movement of air into the compromised lowered areas visibly
landed
primarily in the lowered areas. Radiant heat was applied from the top surface
with
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simultaneous vacuum applied to the bottom surface of the textile fabric. The
sample
passed the British spill test. The cut edges remained resistant to fraying.
Portions of the
fibers in the yarns within the raised areas remained free of adhesive,
maintaining a fibrous
feel. The melted particle resin did protrude over fibers at the bottom of the
lowered areas
but remained below the level of the fibers in the raised areas.
[00110] In an eighth example, the textile fabric was simultaneously
embossed,
stabilized and laminated onto the backing layer. The textile layer was placed
over a low
melting barrier layer and a cushioning layer. Coarse 400-700 micron low-melt
particles or
powder were sifted onto the top surface 412, adding a weight of approximately
0.7 oz./sq.
yd. The composite was embossed and laminated with heat, integrating the three
layers or
elements and producing the composite, for example as illustrated in Fig. 7.
Due to the
presence of resin deposited onto the raised areas, the top surface and the cut
edges of the
composite were stabilized and resisted fraying and fuzzing. The barrier
created by the low-
melt layer was also maintained within the raised areas of the embossed pattern
of the
composite, as the yarns locally shielded the low-melt layer. The textile
fabric and the entire
composite still exhibited permeability to fluids due to leakage within the
compromised
lowered areas of the embossed pattern.
[00111] In a ninth example, fluid penetration resistance was
restored to the embossed
composite of the eighth example. A mixture of high melt index 50/50 coarse and
fine
powders or particles was sifted upon the composite as vacuum was applied to
the bottom
surface. The majority of the particles or powder landed in the lowered areas.
A small
percentage of the finer powder landed in the raised areas, caught by the
interstices
between the yarn filaments. The resulting composite was heated with radiant
heat with
vacuum continuing to be applied to the bottom surface to melt all powders.
Adding
approximately 1.6 oz. of particles or powder was sufficient to fill the
perforations in the low-
melt barrier layer within the lowered areas 504 and to restore the composite
so that it
passed the British spill test. Raising the added weight to 3.5 oz. sealed the
upper surface
totally, with the raised areas still partially fibrous and resistant to
fraying at the cut edges.
[00112] Exemplary embodiments are directed to methods for making
improved textile
fabrics by introducing into the textile fabrics low-melting polymeric
solutions or liquid
dispersions or suspensions of polymeric particles or powders. Suitable
solvents for the
polymeric solutions include, but are not limited to, organic solvents such as
volatile organic
compounds, for example, short-chain alcohols including methanol, ethanol, n-
propanol,
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isopropanol and butanol, ketones, for example, acetone methyl-ethyl ketone,
and other
volatile solvents, for example, toluene, xylene hexane, THF
(tetrahydrofurane), DMF
(dimethylformamide) and DMSO (dimethylsulfoxide). The volatile organic
compounds can
be flashed-off from the textile fabrics using one or more of vacuum and heat.
Suitable
organic solvents also include long-chain organics, for example, oils,
alcohols, naptha, and
petroleum distillates. Long-chain organic solvents dissolve selected polymers
but may be
difficult to remove from the textile fabric, which could contribute to
soiling. In one
embodiment, the solvent is THE. Suitable polymers that are soluble in THE
include
common thermoplastic polymers, for example, polyesters, polystyrenes,
polyurethanes,
polycarbonates, Nylon-6 and polyvinyl alcohols. The THE can be flashed off
after
application to the surface of the textile fabric.
[00113] Water, in combination with surfactants, e.g., soaps,
ethoxylated propylene
glycol or lecithin, in very low percentages by weight is suitable to hold
particulate or
powdered low-melt adhesives in a liquid suspension_
[00114] In one embodiment, the textile fabrics have three-
dimensional surfaces. In
one embodiment, the textile fabrics are incorporated into composites
containing the textile
fabrics on their surfaces. The composites contain one or more additional
layers such as
barrier layers and backing layers. In one embodiment, the barrier layer or
backing layer is
laminated to the textile fabric using a relatively flat heated tool resulting
in a composite with
a flat face or with the general pattern of the texture originally present in
the textile fabric.
Alternatively, lamination of a textile fabric to a backing layer or barrier
layer is achieved
using a three-dimensional heated tool. The three-dimensional heated tool forms
a deeper
and coarser face texture with a depth exceeding the original thickness of the
textile fabric.
[00115] In one embodiment, the textile fabric is a nonwoven layer
formed with
filaments or staple fibers. In one embodiment, the textile fabric is attached
to a cushion
layer. In one embodiment the fabric is attached to a barrier layer.
[00116] In one embodiment, a suspension of polymeric particles is
created by
introducing the polymeric materials into a liquid. Suitable polymeric
particles include, but
are not limited to, low melting polyester, polyethylene, and acrylics.
Suitable liquids include,
but are not limited to, water and water aided by surfactants. In one
embodiment, suitable
suspended polymeric particles or polymeric powders include, but are not
limited to, fine
polymeric powders commercially used in processes, for example, the bonding of
non-
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wovens and coarser powders produced by grinding low melt polymers including
polymers
contained in recycled fabrics or floorcoverings. These powders contain
particles having a
range of particle sizes suitable for use with the textile fabrics.
Alternatively, a polymeric
solution is created by dissolving at least one polymer into a solvent.
[00117] In one embodiment, one or more repellents are added before
or after the
application and curing of polymeric particles or polymeric solution. Suitable
repellents
include but are not limited to acrylic copolymers with PFOA (perfluorooctanic
acid), acrylic
polymers with stearic acid or other hydrophobic functional groups, and other
soil and stain
resistant polymers and finishes such as perfluorocarbons.
[00118] In one embodiment, high-melting or non-melting fine elements
are mixed with
the suspension of polymeric particles or polymeric solution to obtain special
effects. These
fine elements and desired effects include colored particles for aesthetic
purposes, hard
particles to increase resistance to abrasion and particles reacting to
moisture or heat to
produce special visual or functional effects, including but not limited to
breathability,
moisture absorbency and moisture repellency at the surface.
[00119] In one embodiment, the polymeric solutions or suspensions of
polymeric
particles are introduced into the top surface of the textile fabric or to the
entire textile fabric.
Suitable processes for applying the polymeric solutions or suspensions of
polymeric
particles include, but are not limited to, spraying, immersion and squeezing,
and wet
transfer coating. Immersion and squeezing is commonly referred to as padding.
Each
process for applying polymeric solutions or suspensions of polymeric particles
can followed
with the application of additional suspension liquid or solvent or solvent to
reduce or to
eliminate the added adhesive polymer from the surface before the application
of heat.
[00120] In one embodiment, the textile fabric and top surface of the
textile fabric are
flat. Alternatively, the textile fabric is embossed with a three-dimensional
pattern that
creates elevated areas and depressed areas in the textile fabric. In one
embodiment, the
three-dimensional texture or pattern is achieved by embossing the textile
fabric with a
heated tool having a pattern of projections that create the elevated areas and
depressed
areas. In one embodiment, the fabric is formed by yarns that loop into and out
of the top
surface. The looping yams create the surface texture of elevated areas and
depressed
areas. In one embodiment, the slightly textured surface containing the looping
yams is
deeply textured by embossing with the coarse three-dimensional pattern. In one
embodiment, the elevated areas and depressed areas of the embossed textile
fabric define
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a depth between the top of the elevated areas and bottom of the depressed
areas greater
than the original thickness of the textile fabric.
1001211 The polymeric solutions or suspensions of polymeric
particles can be applied
to both the elevated areas and depressed areas or selectively to the elevated
areas. In one
embodiment, the polymeric solutions or suspensions of polymeric particles are
applied to
the elevated areas, for example, using a fine spray or by making wet contact
with a wet
roller or brush, so that the polymeric solutions or suspensions of polymeric
particles do not
proceed into the depressed areas.
[00122] In one embodiment, an additional volume of the liquid in
which the particles
are dispersed or dissolved, i.e., the solvent, is applied to the top surface
of the textile fabric
following introduction of the polymeric solutions or suspensions onto the top
surface.
Suitable methods for applying the addition volume of liquid or solvent
include, but are not
limited to, wiping the surface with the additional volume of liquid or
solvent, spraying the
additional volume of liquid or solvent onto the surface and brushing the
surface with the
additional volume of liquid or solvent. The additional volume of liquid or
solvent is sufficient
to move or migrate at least a portion of the suspended particles or dissolved
polymer away
from and below the top fibrous surface of the textile fabric. In one
embodiment, the
additional volume of liquid or solvent is sufficient to move or migrate all
suspended particles
or dissolved polymer away from and below the top fibrous face. In on
embodiment,
additional volume of liquid or solvent is sufficient to move the suspended
particles or
dissolved polymer to a controlled depth below the top surface. The result of
moving the
suspended particles or dissolved polymer away from the top surface is fibers
on the top
surface protruding above the polymer. The protruding or exposed fibers prevent
excessive
hardening of the top surface of the textile fabric, preserving the textile
look and feel of the
textile fabric.
[00123] In one embodiment, one or more repellents are added to the
additional
volume of liquid or solvent. In one embodiment, high-melting or non-melting
fine elements
are mixed with the additional volume of liquid or solvents to obtain special
effects as
discussed above.
[00124] In one embodiment, the deposited polymer solution or
suspended particles
are activated with heat to melt and set the polymer in situ. In one
embodiment, any added
repellents are cured as the polymers applied to the textile fabric are
activated and set. Heat
is applied to at least a portion of the textile fabric. Preferably, heat is
applied to the entire
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textile fabric. Suitable heat sources include, but are not limited to, radiant
heat, hot air, and
a heated contact surface. In one embodiment, the heated contact surface is
applied to the
textile fabric using low pressure. In one embodiment. vacuum is applied to a
bottom surface
of the fabric opposite the top surface while applying heat to the top surface.
[00125] In one embodiment, activation of the deposited particles or
polymer is
achieved by raising the temperature of the entire textile fabric to a level
sufficient to melt
the polymer or polymer panicles. In one embodiment, the polymer or polymer
particles are
activated when the textile fabric is embossed with the three-dimensional
pattem using a
heated tool equipped with surface projections. In one embodiment the polymer
or polymer
particles are activated when the textile fabric is laminated to additional
layers, for example,
a barrier layer or a backing layer. In one embodiment, a soft and resilient
back-up tool, for
example a silicon rubber back-up tool, is used to emboss the textile fabric
with a depth
exceeding the original thickness of the textile fabric. Altematively, the
textile fabric is
embossed against a conformable cushioning backing, eliminating the need for a
soft back-
up tool as the textile fabric forms into the backing.
[00126] In one embodiment, a water-repellent is incorporated into
the textile fabric. In
one embodiment, a water-repellent coating is applied to the textile fabric and
cured before
the suspension of polymeric particles or polymeric solution is introduced into
the fabric.
Alternatively, the water-repellent coating is applied after the suspension of
polymeric
particles or polymeric solution is introduced and cured with heat
[00127] The advantages and improvements associated with the textile
fabric
containing the activated polymer applied as a suspension of polymeric
particles or as a
polymeric solution vary depending upon the structure of the top surface of the
fabric, the
nature of the surface fibers or yarns, the amount of deposited particles, the
melt
characteristics of the particles, and the structure of the deposited
particles. These
advantages and improvements include, but are not limited to, simple
stabilization of the
elevated areas of yarns and raised areas of fabric versus wear and abrasion,
achieving a
breathable fluid barrier with minimum hardening of the textile fabric surface,
and blocking of
fluid penetration through the textile fabric without excessive hardening and
without
eliminating the fibrous feel of the top surface.
[00128] Referring now to Fig. 10, exemplary embodiments are directed
to a method
for stabilizing a surface of a textile fabric. A desired textile fabric 700 is
selected. The textile
fabric includes a top surface 702 and a bottom surface 704 opposite the top
surface. In one
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embodiment, a nonwoven textile fabric formed with filaments or staple fibers
is selected.
The nonwoven textile fabric has a flat top surface. Alternatively, a textile
fabric containing a
plurality of looping yarns entering and exiting the top surface is selected.
The looping yams
in the plurality of looping yarns include an upper portion of the yarns
adjacent the top
surface. In one embodiment, the textile fabric is a generally planar fabric.
The textile fabric
can be embossed with a coarse pattem containing elevated areas and depressed
areas, as
illustrated, for example, in Figs. 5 and 7. The textile fabric can be
incorporated into a
composite containing one or more additional layers attached to the bottom
surface of the
textile fabric. Suitable additional layers include, but are not limited to,
barrier layers 708 and
backing layers 710 including cushioning backing layers. The composite can also
be
embossed with a coarse pattern.
[00129] In one embodiment, a plurality of polymeric particles 712
are suspended in a
liquid 714 to create a liquid suspension of polymeric particles. As an
alternative to a liquid
suspension of polymeric particles, at least one polymer is dissolved in a
solvent to create a
polymeric solution. In one embodiment, additives are incorporated into the
liquid
suspension of polymeric particles or polymeric solution. These additives have
a melting
point above the melting points of the polymer particles and polymers used to
make the
suspension or solution. Therefore, the melting point of the additives is
greater than any
heat applied to the textile fabric to activate or melt the polymer particles
or polymers. The
additives affect at least one of a color of the textile fabric, an
abrasiveness of the textile
fabric, an absorptiveness of the textile fabric and antimicrobial properties
of the textile
fabric. In one embodiment, a repellent is introduced into the liquid
suspension of particles
or the polymeric solution.
[00130] The liquid suspension of polymeric particles or polymeric
solution is applied to
the top surface of the textile fabric or to the entire textile fabric.
Suitable methods for
applying the liquid suspension of polymeric particles or polymeric solution
include, but are
not limited to, immersion, spraying, rolling and brushing. When the suspension
or solution
is applied only to the surface, an initial volume of the liquid suspension of
polymeric
particles or polymeric solution is applied to the top surface. This initial
volume is sufficient
to penetrate 718 from the top surface into the textile fabric a penetration
depth 722 that is
less than a thickness 724 of the textile fabric. When the textile fabric
includes looping yarns
having an upper portion adjacent the top surface, the penetration depth is
limited to the
upper portion of the looping yams. When the textile fabric has been embossed
with a
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coarse, three-dimensional pattern, the liquid suspension of polymeric
particles or the
polymeric solution is applied only to the elevated areas of the textile fabric
embossed with
the coarse pattern.
[00131] An additional volume of the liquid or the solvent 716 is
added or applied to the
top surface of the textile fabric that already contains the liquid suspension
of polymeric
particles or the polymeric solution. This additional volume is sufficient to
carry at least a
portion of the plurality of polymeric particles of polymer in solution into
the textile fabric to a
point within the textile fabric 720 that is below and away from the top
surface. Preferably,
the additional volume of liquid or solvent is sufficient to carry all of the
polymer particles or
polymer in solution to the point in the textile fabric away from the top
surface. Suitable
methods for applying the additional volume of liquid or solvent include, but
are not limited
to, wet brushing the liquid or solvent onto the top surface, wet rolling the
liquid or solvent
onto the top surface, spraying the liquid or solvent onto the top surface and
combinations
thereof.
[00132] In one embodiment, additives are incorporated into the
additional volume of
liquid or solvent. These additives have a melting point above the melting
points of the
polymer particles and polymers used to make the suspension or solution.
Therefore, the
melting point of the additives is greater than any heat applied to the textile
fabric to activate
or melt the polymer particles or polymers. The additives affect at least one
of a color of the
textile fabric, an abrasiveness of the textile fabric, an absorptiveness of
the textile fabric
and antimicrobial properties of the textile fabric. In one embodiment, a
repellent is
introduced into the additional volume of liquid or solvent.
[00133] Heat, vacuum, forced air or combinations thereof are applied
to at least one
of the top surface, the bottom surface or to the entire the textile fabric or
the composite
containing the textile fabric, for example, in an air circulating oven or
finishing frame.
Suitable mechanisms for applying heat include, but are not limited to,
conduction,
convection and thermal radiation. Conduction utilizes either flat heated
plates or textured heated
plates. The textured heated plates embossed a three-dimensional pattern into
the textile fabric or
composite while transferring heat into the textile fabric. The heated plates
are applied either with or
without pressure applied to the textile fabric. The applied heat is sufficient
to evaporate at least
a portion the liquid or solvent applied to the textile fabric. Preferably, the
applied heat is
sufficient to evaporate all liquid and solvent applied to the textile fabric.
The applied heat is
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also sufficient to melt, in situ, the plurality of polymer particles or the
polymer contained in
solution.
[00134] In one embodiment, the heat-set textile fabric containing
the melted polymeric
particles or melted polymer is needled with smooth fine needles to allow free
water vapor
penetration through the textile fabric.
[00135] The foregoing written description uses examples of the
subject matter
disclosed to enable any person skilled in the art to practice the same,
including making and
using any devices or systems and performing any incorporated methods. The
patentable
scope of the subject matter is defined by the claims, and may include other
examples that
occur to those skilled in the art. Such other examples are intended to be
within the scope
of the claims.
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