U.S. patent application number 17/161698 was filed with the patent office on 2021-08-05 for square hollow fiber.
The applicant listed for this patent is Carl Freudenberg KG. Invention is credited to Hsien Fang Chiou, Michael Hess, Wie Ren Huang, Huan Hsiang Lin, Volker Roehring, Shih Wen Tseng.
Application Number | 20210238770 17/161698 |
Document ID | / |
Family ID | 1000005386021 |
Filed Date | 2021-08-05 |
United States Patent
Application |
20210238770 |
Kind Code |
A1 |
Tseng; Shih Wen ; et
al. |
August 5, 2021 |
SQUARE HOLLOW FIBER
Abstract
A hollow polymeric fiber includes: a tetragonal shape sectional
area having four corner points and four edges. The four corner
points form a square. All four edges are concave or straight. The
fiber has a cross sectional area hollowness ranging from 12 to 25%.
The fiber has a titer in a range of from 4 to 16 dtex.
Inventors: |
Tseng; Shih Wen; (Dayuan,
TW) ; Hess; Michael; (Trippstadt, DE) ; Chiou;
Hsien Fang; (Dayuan, TW) ; Huang; Wie Ren;
(Taoyuan, TW) ; Lin; Huan Hsiang; (Chungli,
TW) ; Roehring; Volker; (Weinheim, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Carl Freudenberg KG |
Weinheim |
|
DE |
|
|
Family ID: |
1000005386021 |
Appl. No.: |
17/161698 |
Filed: |
January 29, 2021 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
D01D 5/253 20130101;
D04H 3/16 20130101; E04F 15/102 20130101 |
International
Class: |
D01D 5/253 20060101
D01D005/253; D04H 3/16 20060101 D04H003/16; E04F 15/10 20060101
E04F015/10 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 30, 2020 |
EP |
20 154 602.5 |
Claims
1. A hollow polymeric fiber, comprising: a tetragonal shape
sectional area having four corner points and four edges, wherein
the four corner points form a square, wherein all four edges are
concave or straight, wherein the fiber has a cross sectional area
hollowness ranging from 12 to 25%, and wherein the fiber has a
titer in a range of from 4 to 16 dtex.
2. The hollow polymeric fiber according to claim 1, wherein a shape
of each corner resembles an acute angle, or a right angle with
straight or concave legs (arrow tip).
3. The hollow polymeric fiber according to claim 1, wherein a
diameter of an outer circle of the tetragonal shape is in a range
of from 10 .mu.m to 100 .mu.m.
4. The hollow polymeric fiber according to claim 1, wherein the
fiber is prepared by polymer melt or solution spinning through a
spinneret comprising a pattern of orifices, wherein one single
fiber is formed by passing a polymer melt though an arrangement of
four slots, and wherein each slot of the four slots forming one
fiber has a shape that resembles an acute angle, or a right angle
with straight or concave legs.
5. The hollow polymeric fiber according to claim 4, wherein the
fiber is prepared by melt or solution spinning through the
spinneret comprising the pattern of orifices, and wherein the
fibers exiting the spinneret are subjected to a one step drawing
process.
6. The hollow polymeric fiber according to claim 4, wherein a
length of two legs of each slot is in a range of 0.4 to 0.6 mm and
a width of each leg is in a range of 0.08 to 0.13 mm.
7. The hollow polymeric fiber according to claim 4, wherein a ratio
of a length to a width of legs of each of the slots is in a range
of 4:1 to 6:1.
8. The hollow polymeric fiber according to claim 1, wherein the
fiber is comprised of thermoplastic polymers.
9. A fiber composition, comprising: at least one of the fiber of
claim 1; and at least one fiber which is selected from a group
consisting of: fibers having different denier values compared to
the fiber according to claim 1, or fibers having different shapes
compared to the fiber according to claim 1.
10. A nonwoven fabric, comprising: the fiber according to claim
1.
11. A method for preparing a nonwoven fabric, comprising: employing
fibers comprising at least one hollow polymeric fiber according to
claim 1.
12. The method according to claim 11, wherein the nonwoven fabric
is prepared by polymer melt or solution spinning of the fibers
through a spinneret comprising a pattern of orifices, wherein one
single fiber is formed by passing the polymer melt though an
arrangement of four slots, and wherein each slot of the four slots
forming one fiber has a shape that resembles an acute angle or a
right angle with straight or concave legs.
13. The nonwoven fabric according to claim 10, wherein the fabric
comprises a tufted nonwoven fabric.
14. The nonwoven fabric according to claim 10, further comprising a
tuft-backing containing the fiber.
15. A carpet tile, comprising: the hollow polymeric fiber according
to claim 1.
16. The hollow polymeric fiber according to claim 3, wherein the
diameter of the outer circle of the tetragonal shape is in a range
of from 15 .mu.m to 50 .mu.m.
17. The hollow polymeric fiber according to claim 4, wherein each
of the four slots forms an arrow tip.
18. The hollow polymeric fiber according to claim 7, wherein the
ratio of the length to the width of legs of each of the slots is in
a range of 4.5:1 to 5.5:1.
19. The hollow polymeric fiber according to claim 8, wherein the
thermoplastic polymers are selected from a group consisting of:
polyesters, polyolefines, polyamides, polylactates, copolymers
derived thereof, and mixtures thereof.
20. The fiber composition according to claim 9, wherein the fibers
having different denier values are in a top-down arrangement, or
the fibers having different shapes are in a top-down arrangement.
Description
CROSS-REFERENCE TO PRIOR APPLICATION
[0001] Priority is claimed to European Patent Application No. EP 20
154 602.5, filed on Jan. 30, 2020, the entire disclosure of which
is hereby incorporated by reference herein.
FIELD
[0002] The present invention relates to a polymeric fiber
comprising at least one square hollow region, filters and carpets
comprising the polymeric fiber, a nonwoven fabric comprising the
polymeric fiber, the use of the polymeric fiber and a capillary
spinneret orifice comprising a pattern of arranged holes designed
to provide said polymeric fibers.
BACKGROUND
[0003] Polymeric fibers are obtained by various known spinning
processes. Fibers from polymers that become flowable and pliable
under heating, in particular thermoplastics, can be produced by
melt spinning processes. Melt spinning is a specialized form of
extrusion, wherein a polymeric material is melted in order to
obtain a polymer melt which is then passed through a spinneret,
i.e. a type of die used to form continuous filaments. In a usual
embodiment, the spinneret comprises a metal plate with an
arrangement (pattern) of small holes through which the polymer melt
is passed into the air or a liquid for solidification and fiber
formation. The design of the spinneret varies greatly. Conventional
spinneret orifices are circular and produce fibers that are round
in cross section. Capillary spinneret orifices enable extrusion of
filaments with small diameters of one denier or less. The extruded
molten filaments exiting the spinneret are cooled to obtain the
final fibers which have the shape of the outlet openings of the
spinneret plate. It is known to use spinneret orifices having
shaped holes to obtain fibers of different shapes and with various
characteristics.
[0004] Different shapes of fibers and multi-lobal fibers have been
known for many years. The known fibers can be of a triangular cross
section, so called trilobal fibers. The fibers can be of a square
shape, they can be a star shape fiber with four, five, six or more
fingers. Furthermore, fibers showing flat oval, T-shape, M-shape,
S-shape, Y-shape, or H-shape cross sections are known.
[0005] The single fibers (filaments) can be spun to yarns, and a
number of yarns can be plied together for producing threads.
[0006] One special aspect is the use of polymer fibers for the
manufacture of carpets. Tufted carpets are multilayer, pile
textiles. They are manufactured on special machines on which the
pile yarn is joined but not tied, by means of needles, with a base
layer, which in the case of carpets today consists almost
exclusively of synthetic fibers. The anchoring of the pile yarn is
accomplished by a subsequent coating of the reverse side of the
base layer with natural or synthetic rubber or with polyvinyl
chloride (PVC). The rubber coating moreover is joined to a
so-called secondary backing, which as a rule consists of an
elastomer foam or a woven or non-woven textile material.
[0007] Tufted products find many uses, for example, as carpets,
runners, textile tiles, bedspreads, bath mats, etc. In their
production, the base layer in particular is of considerable
importance. The task of base layer is a safe anchoring of the pile
yarn.
[0008] The term "tufting" refers to a technology for the production
of three-dimensional textile sheets. It is the process most
frequently employed worldwide for preparing carpets. Tufting works
on the principle of a sewing machine. Needles insert the so-called
pile yarn into a base material (woven or non-woven fabric), the
so-called primary backing or support. The needles stitch through
the base material; before the needles are running back again, the
inserted pile yarn is held by loopers. This produces loops (pile
knots) on the top side of the tufting fabric. In this way, a
so-called loop-pile carpet is obtained. If the loops are cut open
with a knife, a velour carpet (cut-pile carpet) is formed.
Frequently, the knife is already attached to the looper, so that
the holding and cutting of the pile is done in one operation. In
order to hold the stitched pile yarn tight, a secondary backing or
latex layer must be applied. This process is referred to as
lamination or integration.
[0009] EP 1619283 describes a method for producing a tufted
nonwoven fabric, wherein fibers, which are divergent from a round
fiber cross section, are used for tuft backing.
[0010] EP 1878817 describes square fibers for airtightness fabrics.
The disclosed fibers may be hollow or non-hollow fibers. Hollow
square fibers are solely mentioned as one alternative. However, the
shape and the dimension of the hollow region of the fibers are not
disclosed.
[0011] WO 2018/113767 describes hollow polyester fibers, which have
a cross-sectional hollowness ranging from 20.0% to 45.0%. The fiber
itself and the hollow have a crimped shape, wherein the radius of
curvature of the crimped shape being 10.0 mm-50.0 mm.
[0012] WO 2006/133036 and WO 2006/020109 describe mixtures of
various shaped fibers to provide improvements in opacity, barrier
properties, and mechanical properties. The variety of cross
sections include solid round fibers, hollow round fibers,
multi-lobal solid fibers, hollow multi-lobal fibers, square shaped
fibers, crescent shaped fibers, and any combination thereof.
[0013] CN 203999944 describes a square hollow fiber. The square
hollow fiber is formed by connecting two L-shape parts. The side
lengths are from 0.04 to 1.00 mm, the width lengths are from 0.001
to 0.009 mm, the minimum distance of the L-shape holes is from
0.001 to 0.008 mm, the inner and outer radius of the arc formed by
the L-shape is 0.001 to 0.009 mm, the angel is 90.degree.. The
present invention are distinct from CN 203999944 in the dimension
of the square hollow, an outer diameter and the shape of the
fiber.
[0014] CN 101748501 describes square hollow fiber and a production
method thereof. The cross section of the fiber has a square hollow
shape. The length ratio of the longest side to the shortest side is
1-2:1, the angle is from 45 to 135.degree., the hollowness of the
fiber is from 12 to 25%. The distinguishing feature is the ratio of
the longest side to the shortest side, which is 5:1 to 6:1.
[0015] US 2003/039827 relates to a fiber having a square cross
section and a square shaped hollowness. The sides are slightly
concave. The hollowness ranges from 5 to 30%. The yarn described in
US 2003/039827 may impart color strength and/or a glitter effect to
the carpet made therefrom. Furthermore, this document discloses a
spinneret plate, which has a cluster of four orifices centered
about the central point. Each orifice includes a generally
isosceles-triangle-shaped major portion from which extends a pair
of legs, each leg of one orifice being spaced from the leg of an
adjacent orifice to define a gap. The shape and the angels of the
orifice of US 2003/039827 are different from the orifice according
to the invention. Due to the design of the orifice, it is not
feasible to spin a fine fiber having a titer in the range of 4 to
16 dtex.
[0016] CN 206494991 relates to a special -shaped spinneret plate
and is formed by four quadrangle hole interval arrangements. The
rounded square fiber has a square hollowness. The hollowness is 15
to 18%. The textiles made of the fibers may be windproof and water
repellent. Due to the design of the orifice, it is not feasible to
spin a fine fiber having a titer in the range of 4 to 16 dtex.
[0017] JP 2932721 relates to a polyester yarn, wherein the fiber
seems square shaped and has a polygonal hollow cross section. The
hollow part is 10-40%. The polyester yarn may impart the textiles
and clothing made therefrom a refreshing feeling and a glittery
appearance. The shape and the angels of the orifice of JP 2932721
are different from the orifice according to the invention. Due to
the design of the orifice, it is not feasible to spin a fine fiber
having a titer in the range of 4 to 16 dtex.
[0018] CN 2883409 discloses a spinneret for spinning hollow fibers
with rectangular cross-section. The textiles made of the fibers may
be windproof and water repellent. The spinning pore of spinneret is
a rectangular body with 1, 2 or 4 slits; the four corners of the
rectangular body are composed of two perpendicularly-crossed long
slits and an outward extending short slit. The shape and the angels
of the orifice of CN 2883409 are different from the orifice
according to the invention. Due to the design of the orifice, it is
not feasible to spin a fine fiber having a titer in the range of 4
to 16 dtex.
[0019] CN 105714390 discloses a high-softness composite fiber
bundle. The composite fiber bundle has a bundle structure which is
formed by gathering 100 to 200 monofilament fibers. The interior of
each monofilament fiber is in a hollow circular structure. The
exterior of each monofilament fiber is a square structural layer.
An inward concave arc is arranged on each side of the square
structural layer. A water absorbing layer is arranged between the
interior and the exterior of each monofilament fiber. Gaps are
formed among the monofilament fibers, so that the stagnant air
amount of the fibers can be increased. The water absorbing layer is
arranged in each monofilament fiber. The shape and the angels of
the orifice of CN 105714390 are different from the orifice
according to the invention. Due to the design of the orifice, it is
not feasible to spin a fine fiber having a titer in the range of 4
to 16 dtex.
[0020] In processes known from the prior art, hollow fibers are
formed by passing through one-clot connected orifices.
[0021] The use of the square hollow fibers for tufted nonwoven
backing is not described by the prior art.
[0022] Most of tufted nonwoven backings are filaments in round
shape. The round shape gives only a single contact point on the
edges while the pile yarn is inserted into the backing by needles
during the tufting process.
[0023] Currently, a demand can be seen to fibers, which have
lighter weight and/or fibers, which increase the contact and
friction between filaments and pile yarn. In both cases the
maintenance of excellent performance of pile-holding capability at
tufting is desired. Therefore, development of fibers meeting the
requested increase of the contact and friction between filaments
and pile yarn, with improve pile-holding performance is
desired.
SUMMARY
[0024] In an embodiment, the present invention provides a hollow
polymeric fiber, comprising: a tetragonal shape sectional area
having four corner points and four edges, wherein the four corner
points form a square, wherein all four edges are concave or
straight, wherein the fiber has a cross sectional area hollowness
ranging from 12 to 25%, and wherein the fiber has a titer in a
range of from 4 to 16 dtex.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] The present invention will be described in even greater
detail below based on the exemplary figures. The invention is not
limited to the exemplary embodiments. Other features and advantages
of various embodiments of the present invention will become
apparent by reading the following detailed description with
reference to the attached drawings which illustrate the
following:
[0026] FIG. 1 illustrates a square hollow polymeric fiber according
to the invention.
[0027] FIG. 2 illustrates a mixture of square hollow polymeric
fiber according to the invention and round non-hollow fibers (solid
fibers).
[0028] FIG. 3 illustrates a square hollow polymeric fiber according
to the invention.
[0029] FIG. 4: shows a detailed view of the four slots of spinneret
forming a hollow polymeric fiber according to the invention.
DETAILED DESCRIPTION
[0030] In an embodiment, the present invention provides optimized
fibers having both a lighter weight and an increase in the contact
and friction between filaments and pile yarn in order to provide
excellent pile-holding performance.
[0031] The problem underlying of the invention is solved by hollow
polymeric fibers comprising a tetragonal square shape sectional
area.
[0032] The polymeric fibers according to the invention have the
following advantages: [0033] The contact surface between fiber and
pile yarn is increased by both hollowness and tetragonal shaped
sectional area of the inventive fiber. [0034] The hollowness of the
fiber increases the outer surface of each fiber. [0035] The
tetragonal shaped sectional area of the fiber enlarges the contact
from the fiber and the pile yarn. [0036] The contact surface
between pile yarn and inventive fiber is increased by 20 to 60%
compared to round fibers.
[0037] The invention relates to hollow polymeric fiber comprising a
tetragonal shape sectional area, wherein: [0038] the four corner
points form essentially a square, [0039] all four edges are
straight or concave, [0040] the fiber has a cross sectional area
hollowness ranging from 12 to 25%.
[0041] In particular, the invention relates to hollow polymeric
fiber comprising a tetragonal shape sectional area, wherein: [0042]
the four corner points form essentially a square, [0043] all four
edges are concave or straight, [0044] the fiber has a cross
sectional area hollowness ranging from 12 to 25%, [0045] the fiber
has a titer in the range of from 4 to 16 dtex.
[0046] The invention also relates to a nonwoven fabric comprising
the polymeric fiber as defined above and below.
[0047] The invention also relates to a carpet tile comprising the
polymeric fiber as defined above and below.
[0048] The invention also relates to the use of the polymeric fiber
as defined above and below for the preparation of nonwoven
fabrics.
[0049] The invention also relates to a capillary spinneret orifice
comprising a pattern of arranged holes designed to provide
polymeric fibers as defined above and below.
[0050] In the sense of the invention the term "outer circle
r.sub.o" is the minimum circle that completely surrounds the cross
sectional area of the fiber.
[0051] The term "fiber" denotes an elongated body, wherein the
length dimension is greater than the transverse dimension of width
and thickness. Thus, the term "fiber" includes (single) filament,
ribbon, stip etc. Fibers are understood to mean staple fibers or
continuous fibers referred to as a filament. The fibers may also be
combined to form fleeces, in particular bonded fleeces, for
nonwoven fabric.
Fibers:
[0052] The polymeric fibers according to the invention have a
generally tetragonal shape sectional area, preferably a square
shaped sectional area. The area that is formed if each neighbor
corner points of the four outer corner points are connected with
imaginary lines is essentially a square. Each outer corner point is
connected with its two adjacent outer corner points with a straight
or concave connecting section. All four outer edges are
independently of one another straight or concave. Preferably, the
shape of each outer corner resembles an acute angle, or essentially
right angle with straight or concave legs. Thus, preferably, the
shape of each outer corner resembles an arrow tip, wherein two
straight or concave lines start from each arrow tip and are
connected with the adjacent arrow tip. In a preferred embodiment,
the outer shape of the fiber has a perfect tetragonal shape
(straight edges). The hollow polymeric fiber has preferably a
diameter of the outer circle of the tetragon in the range of from
10 .mu.m to 100 .mu.m, preferably from 15 .mu.m to 50 .mu.m.
[0053] The fiber has a cross sectional area hollowness ranging from
12 to 25% based on the total cross sectional area of the fiber. The
total cross sectional area of the fiber is the sum of the cross
sectional area of the hollowness and the cross sectional area of
the remaining fiber.
[0054] Preferably, the fiber has a cross sectional area hollowness
ranging from 15 to 20% based on the total cross sectional area of
the fiber.
[0055] The shape of the inner hollowness is not crucial. Thus, the
shape of the hollowness may be round shape, oval-shape, triangular
shape, tetragonal shape, square shape, T-shape, M-shape, S-shape,
Y-shape, or H-shape.
[0056] In a further embodiment the hollowness has a round
shape.
[0057] In preferred embodiment the fiber according to the invention
has only one single hole.
[0058] The polymeric fiber according to the invention is prepared
by melt or solution spinning through spinneret orifices. For melt
spinning, a polymer in the molten state can be fed to a spinneret
plate, e.g. by means of an extruder. Preferably, one single fiber
is formed by 4 slots in the spinneret, wherein the slots are not
connected. Thus, one single fiber is formed by the combined
plasticized polymer melt exiting the four slots. In other words,
the shape of the fiber is formed by four pieces of slots wherein
the capillary of the orifices has an arrow tip shape as explain
above. By dividing the polymer melt into four partial strands a
higher rate of hollowness can be achieved. Preferably, an air flow
is injected from four gaps of each side forming the fiber shape. In
particular, each slot of the four slots forming one fiber has a
shape that resembles an acute angle, or essentially right angle
with straight or concave legs. Especially, each of the four slots
has the form of an arrow tip. Preferably, the length of the two
legs of each slot is in the range of 0.4 to 0.6 mm. Preferably, the
width of each leg is in the range of 0.08 to 0.13 mm. The outer
circle of the four slots forming a tetragon is preferably in the
range of from 0.98 to 1.10 mm, in particular 0.95 to 1.03 mm.
[0059] Preferably, in the process of the invention the fibers
exiting the spinneret are subjected to a one step drawing process
(stretching process). For the drawing process, e.g. the newly
formed fibers exiting the orifices of the spinneret are first
passed through a heated zone, where such a temperature is set as
can lead to plastic deformation of the fibers. Subsequent to the
heated zone there can be a cooling zone. In this zone the
temperature of the fibers is lowered to below the glass transition
temperature T.sub.g. Cooling can be carried out in various ways
known to the skilled person. When the fiber bundle leaves the
cooling zone, the bundle's temperature should be low enough that it
can be passed over or along rotating or static guiding elements
without the fibers or the bundle being permanently deformed. For
drawing, the speed of the fibers (the spinning speed) exiting the
spinneret orifices and, if present, the heating and the cooling
zone is fixed. The speed can be set to a certain value e.g. by
passing the fiber bundle several times across one or more godets.
The godets can be heated if desired. By stretching and/or drawing
the fibers obtain their final mechanical properties and morphology,
in particular their fineness.
[0060] In the one-step drawing process according to the invention
the fibers (i.e. the as-spun product) are drawn immediately after
the spinning speed has been fixed.
[0061] In a preferred embodiment of the process of the invention
the fibers exiting the spinneret are stretched aerodynamically to
obtain the desired strength. The filaments obtained in the spinning
process can be deposited forming a nonwoven fabric. E.g. the
filaments obtained in the spinning process are deposited on a
deposit belt on which they come to lie on top of one another.
[0062] In a further preferred embodiment of the process of the
invention the spinning process can be performed as melt-blown
process in which the melt exiting from the spinnerets is entrained
by an air stream at high pressure and high temperature, so that
fibers with a low thickness are formed. These fibers can also be
deposited to form a nonwoven fabric. This is done primarily on
deposit drums.
[0063] It was found that if the fibers are drawn in one step,
square hollow fibers with improved design and improved application
properties are obtained.
[0064] Preferably, the ratio of the length to the width of the legs
of the each slots is in the range of 4:1 to 6:1, preferably 4.5:1
to 5.5:1.
[0065] The titer of the fibers can be measured in terms of linear
mass density, i.e. the weight of a given length of the fiber. It is
preferred that the polymeric fibers according to the invention have
a titer in the range of from 4 to 16 dtex (SI-unit: 1 dtex=1
g/10000 m).
Material of the Fibers:
[0066] In principle, the polymeric fibers according to the
invention may be formed from any fiber-forming polymers, i.e.
polymers that can be converted into a melt or solution that
satisfies the conditions of spinnability.
[0067] Thermoplastic polymeric materials may be used in the present
invention. In the sense of the invention thermoplastic polymers are
those which can be reversibly deformed above a certain temperature,
whereby this process can be repeated as often as desired. Below
this specific temperature, these are non-deformable substances. The
thermoplastic polymeric material must have rheological
characteristics suitable for melt spinning. The molecular weight of
the polymer must be sufficient to enable entanglement between
polymer molecules and yet low enough to be melt spinnable. For melt
spinning, thermoplastic polymers having molecular weights below
about 1,000,000 g/mol, preferably from about 5,000 g/mol to about
750,000 g/mol, more preferably from about 10,000 g/mol to about
500,000 g/mol and even more preferably from about 50,000 g/mol to
about 400,000 g/mol. The thermoplastic polymeric materials must be
able to solidify relatively rapidly, preferably under extensional
flow, and form a thermally stable fiber structure, as typically
encountered in known processes, such as a spin draw process for
staple fibers or a spunbond continuous fiber process. Preferred
polymeric materials include, but are not limited to, polyesters,
polyolefines, polyamides, polylactates, halogen-containing
polymers, polyacrylates, polyvinyl acetates, polyvinyl alcohols,
polycarbonates, polyurethanes, polystyrenes, polyphenylene
sulfides, polysulfones, polyoxymethylenes, polyimides copolymers
derived thereof and mixtures thereof.
[0068] Suitable polyolefins are selected from polyethylene,
polypropylene, poly(1-butene), polyisobutylene, poly(1-pentene),
poly(4-methylpent-1-ene), polybutadiene, polyisoprene and
polyolefin containing blends. Suitable polyethylenes are selected
from HDPE, LDPE, LLDPE, VLDPE; ULDPE and UHMW-PE. Suitable
polyolefin blends comprise at least one polyolefin, especially
polyethylene, polypropylene or ethylene-propylene-copolymers and at
least one different polymer. The different polymer is e.g. selected
from graft or copolymers made of polyolefins and
.alpha.,.beta.-unsaturated carboxylic acids or carboxylic acid
anhydrides, polyesters, polycarbonates, polysulfones, polyphenylene
sulfides, polystyrenes, polyamides or a mixture of two or more of
the mentioned different polymers.
[0069] Suitable halogen-containing fiber-forming polymers are
polyvinylchloride (PVC), polyvinylidene chloride (PVDC),
polyvinylidene fluoride (PVDF) and polytetrafluoroethylene
(PTFE).
[0070] The polymeric fibers according to the invention may also
comprise or consist of at least one non-thermoplastic polymeric
material. Suitable non-thermoplastic polymeric materials are
regenerated cellulose (in particular viscose rayon, lyocell),
cotton, wood pulp, etc. and mixtures thereof. The polymeric fibers
from non-thermoplastic polymeric material may be produced e.g. by
solution or solvent spinning. Regenerated cellulose can be produced
by extrusion through capillaries into an acid coagulation bath.
[0071] In particular, the polymer fibers according to the invention
comprise a polymer selected from polyolefins, polyesters,
polyamides and copolymers and mixtures thereof.
[0072] The polymeric fibers according to the invention can be
constructed as mono- or multicomponent filaments. A suitable
embodiment is a multi-component filament having a polyester, in
particular a polyethylene terephthalate, as core material and a
co-polyester as finger material.
[0073] The polymeric fibers according to the invention are suitable
for the formation of fabrics, e.g. nonwovens that can be
advantageously used as filters. The filter substrates may consist
of single type of filaments or a combination of different type of
filaments.
[0074] The polymeric fibers according to the invention are suitable
for the formation of fabrics, e.g. nonwovens that can be
advantageously used as carpet tiles. The carpet tiles substrates
may consist of single type of filaments or a combination of
different type of filaments.
[0075] Different types of filaments can be produced in one step by
so called multi-shape spinning by using a spinneret with a
combination of orifices having different shapes. Thereby, it is
possible to produce multi-layers fabric in one steps. Thus, it is
possible to produce filters with different layers, e.g. having a
different air permeability. For example, the resulting filter can
consist of layers which indirection of the air stream have a
gradient from higher to lower air permeability. The invention
allows the production of filters that are effective at removing
airborne particles and are characterized by a low pressure drop
which is retained over long time of application.
[0076] The design of the filaments and the resulting filters can be
optimized according to the demanded air flow/air penetration.
[0077] It is possible to combine fibers of different shapes and/or
different sizes: e.g.
[0078] a) Combination of filaments having the same shape but a
different denier value (e.g. 12 and 6 denier), e.g. fibers
according to the invention, preferably in a top-down
arrangement.
[0079] b) Combination of filaments having different shapes, e.g.
round shape, oval-shape, triangular shape, tetragonal shape, square
shape, T-shape, M-shape, S-shape, Y-shape, or H-shape. E.g. a
combination of round fibers and fibers according to the invention,
preferably in a top-down arrangement (two layer fabric).
[0080] c) Combination of filaments having different shapes, e.g.
round shape, oval-shape, triangular shape, tetragonal shape, square
shape, T-shape, M-shape, S-shape, Y-shape, or H-shape. E.g. a
combination of round fibers and fibers according to the invention
and round fibers, preferably in a top-down arrangement (three layer
fabric).
[0081] d) Combination of filaments having different shapes, e.g.
round shape, oval-shape, triangular shape, tetragonal shape, square
shape, T-shape, M-shape, S-shape, Y-shape, or H-shape. E.g. a
combination of fibers according to the invention and round fibers
and fibers according to the invention (three layer fabric).
[0082] e) Combination of filaments having different shapes, e.g.
fibers according to the invention and shapes selected from
triangles, 4-, 5-, 6-, 7-, 8-pointed stars, ellipse, H-shape,
double H-shape and combinations thereof in a top-down arrangement
(two and multi-layer fabric).
Process:
[0083] The polymeric fibers according to the invention in one
embodiment are spunmelt fibers. Melt-spinning in the sense of the
invention is a kind of thermoplastic extrusion. Melt-spinning
includes spunlaid processes, meltblown processes and spunbond
processes. Those processes are known to a person skilled in the
art.
[0084] The first step in producing a fiber is usually a compounding
or mixing step. In the compounding step, the raw materials are
heated, typically under shear. The shearing in the presence of heat
will result in a homogeneous melt of the thermoplastic material and
optional non-thermoplastic material. The obtained melt is then
placed in an extruder, where the material is mixed and conveyed
through capillaries to form fibers. The fibers are then attenuated
and collected. The fibers are preferably substantially continuous
(i.e., having a length to diameter ratio greater than about
2500:1), and will be referred to as spunlaid fibers.
[0085] In a preferred embodiment of the process according to the
invention, a spinneret is used comprising capillary spinneret
orifices forming a pattern of arranged holes designed to provide
polymeric fibers as defined above.
[0086] The spinneret comprising a pattern of arranged holes
designed to provide polymeric fibers as defined above is also one
aspect of the invention.
[0087] In a preferred embodiment the spinneret comprises orifices
consisting of four slots, wherein each slot has a shape that
resembles an acute angle, or essentially right angle with straight
or concave legs (arrow tip).
[0088] The fibers may be converted to fabrics by different bonding
methods. In a spunbond or meltblown process, the fibers are
consolidated using known industry standard technologies. Typical
bonding methods include, but are not limited to, calender (pressure
and heat), through-air heat, mechanical entanglement, hydraulic
entanglement, needle punching, and chemical bonding and/or resin
bonding. For the pressurized heat and through-air heat bonding
methods fibers are required that are thermally bondable. The fibers
may also be woven together to form sheets of fabric. This bonding
technique is a method of mechanical interlocking. The fibrous
fabric may then be incorporated into an article.
[0089] Another aspect of the invention is a textile structure, e.g.
in the form of woven fabric, knitted fabric, laid scrim, or
nonwoven fabric, comprising the polymeric fibers according to the
invention. A textile structure in the sense of invention is a
combination of fibers or fiber bundles. It can be single or
multi-layered. A textile structure in the context of the present
invention is defined as woven fabric consisting of at least one
layer, preferably more than one layer, single- or multi-layered
woven fabric, single- or multi-layered nonwoven fabric single- or
multi-layered knitted fabrics, single- or multi-layered laid scrim
fabrics, preferably several layers, consisting of parallel fibers,
fiber bundles, yarns, twists or ropes, whereby the individual
layers of the parallel fibers or fiber bundles of yarns, twists or
ropes may be twisted relative to one another, or nonwovens.
[0090] A particular aspect of the invention is a nonwoven fabric
comprising the polymeric fibers according to the invention.
Therefore, a further aspect of the invention is the use of the
polymeric fibers as defined above for the preparation of a nonwoven
fabric.
[0091] Nonwoven fabric is also called spunbonded nonwoven,
spunlaid, spunbond or spunbonded fabric.
[0092] Generally, nonwoven fabric are made from fibers of
practically unlimited length and are made in one continuous
process.
[0093] The nonwoven fabric is preferably obtained by thermal
bonding from fibers obtained by meltblowing. Thus, the nonwoven
fabric preferably comprises meltblown polymer fibers, in particular
at least one hollow polymer fiber according to the invention. In a
special embodiment the nonwoven fabric comprises at least one
polymer fiber according to the invention and at least one fiber
which is selected from: [0094] fibers having different denier
values compared to the polymeric fiber according to the invention,
[0095] fibers having different shapes compared to the polymeric
fiber according to the invention.
[0096] The proportion of fibers according to the invention is
preferably 1 to 99% by weight, based on the total weight of the
fibers.
[0097] The specific cross-sectional shape of the fibers different
from the fiber according to the invention plays a secondary role,
provided that under the stated conditions a nep adhesive force with
respect to a tuft yarn is achieved in the stated range. Fibers
different from the hollow fibers according to the invention having
a triangular cross section, referred to as trilobal fibers, fibers
having a star shape with four, five, or more arms, or fibers having
a flat, oval, T-shaped, M-shaped, S-shaped, Y-shaped, or H-shaped
cross section may be used.
[0098] In the technical field of nonwovens, the term "meltblowing"
essentially refers to a spinning process, in which thermoplastic
fiber forming polymer is melted, pumped through die holes and
enters high-speed air streams when leaving the spinning nozzles.
The streams of hot air normally exit from the sides of the nozzles,
guide the melted polymer streams and lead to formation of very fine
filaments. The filaments are deposited on a collector screen,
whereby a relatively fine, typically self-bonded nonwoven web is
formed. The meltblow process is different from conventional
spunlaid technology, in which the emerging polymer fibers are not
guided by air streams from nozzles in the spinneret, but normally
only drawn onto a conveyor belt by suction.
[0099] When the meltblown polymer fibers are collected on a surface
below the meltblowing device, the nonwoven is obtained.
Subsequently, the nonwoven is thermally bonded to become the
nonwoven fabric. The process is a single step process.
[0100] Methods are known in the art how to modify a meltblow
process, such that a broader fiber diameter distribution is
obtained. For example, this can achieved by adjusting the air
streams, which take up the emerging polymer fibers, such that they
are subjected to higher turbulence and strongly swirled.
Alternatively, different fiber diameters can be obtained by
simultaneous spinning of fibers with different diameters from
different spinning devices into a single nonwoven.
[0101] In a preferred embodiment, meltblowing is carried out in a
concentric air meltblowing process. As used herein, this term
refers to a meltblowing process, in which multiple rows of spinning
dies are used, each of which are surrounded by air nozzles. As
described in the art, a relatively broad fiber distribution can be
obtained accordingly.
[0102] In a preferred embodiment, meltblowing is carried out in a
multi row meltblowing process. As described in the art, the fiber
diameter distribution can be enhanced in such a multi-row meltblow
process, in which a large number of spinning dies are extruded in
parallel.
[0103] In a highly preferred embodiment, meltblowing is carried out
in a concentric air multi row meltblowing process. In this
embodiment, a concentric air meltblow method is carried out as a
multirow process. Such a method is especially suited for obtaining
a broad fiber diameter distribution.
[0104] A concentric air multi row meltblowing process is typically
carried out as follows. The molten polymer and hot air are fed in
parallel through a spinneret through an array of multiple dies and
nozzles. The emerging polymer fibers are surrounded by concentric
nozzles from which hot air is blown. After exit from such die
openings, the molten polymer is immediately stretched by hot air
from the surrounding nozzle. The overall system creates a high
turbulence, such that sections of the fibers are formed having
small and large fiber diameters. The fibers are blown onto a
collector and swirled. The collector may comprise suction means.
The fibers are accumulated on the collector surface to obtain a
nonwoven web, which can subsequently be converted into a nonwoven
fabric by thermal bonding, if desired. Thus, the nonwoven fabric is
prepared in a one step drawing process.
[0105] Alternatively or in addition, multiple (i. e. two, three or
more) multi row meltblowing devices can be arranged in parallel for
spinning different polymer fibers into the same nonwoven. In such a
process, all polymer fibers, which are spun from different devices,
are mixed in the process and laid down simultaneously on a single
conveyor belt. A nonwoven is obtained comprising the different
fibers, which is preferably homogenous. The fiber diameter
distribution can be increased by combining of two or more
meltblowing devices, which produce different polymer fibers. When
two multi-row spinnerets are arranged at a specific angle, the
polymer fibers are blown onto a collector to produce hybrid
nonwoven webs of two different fiber types which are strongly
intermingled.
[0106] Various process modifications are known and described in the
art for adjusting the composition and properties of the nonwovens.
Each spinneret can be fed by an independent extruder, or both
spinnerets can be fed from a single extruder. With independent
extruders, two different polymers can be spun onto the collector to
produce hybrid nonwoven webs. For example, a polymer having a low
melting point can be combined with another polymer having a higher
melting point, such as polyethylene and polyester. When
polyethylene and polyester are combined and calendered,
polyethylene can be molten at least in part to adhere the polyester
fibers to each other; resulting in a high strength of the nonwoven
fabric and a small pore size. It is also possible to combine
relatively fine fibers meltblown from a first spinneret with
relatively coarse fibers spunlaid from a second spinneret. Such a
method can be used for obtaining a high fiber diameter variation.
Moreover, polymer materials can be combined, which confer specific
properties to the nonwoven, for example by combining polymers
having a different meltflow index. For example, a first meltblown
polymer could have a meltflow index of 600 or less, whereas a
second polymer could have a meltflow index of 600 or higher. The
higher the meltflow index is, the lower the melt viscosity is.
Thus, finer fibers are produced from the polymer which is meltblown
having a higher meltflow index, whereas thicker fibers are obtained
from the polymer having a lower meltflow index.
[0107] The nonwoven can also be obtained by other production
processes, in which two different fiber types are spun in parallel
and combined in the same spinning process. For example when a
concentric air multi-row meltblowing process is carried out in
parallel with a second spinning process, a mixed nonwoven of
intermingled fibers can be obtained on a single deposit. For
example, a concentric air multi-two meltblowing process can be
combined with a conventional meltblowing process, when two
spinnerets are applied in parallel for producing polymer fibers.
For example, such a method can be adjusted such that relatively
fine fibers are added to the emerging nonwoven from the
conventional meltblowing process, whereas fibers having a higher
diameter are added from the concentric air multi-row meltblowing
process.
[0108] In another embodiment, the nonwoven is prepared in a single
meltblowing process from two, three or more different types of
polymers, which yield two, three or more different types of polymer
fibers. Thereby, a nonwoven is obtained comprising two or more
different fibers having different structure, polymer composition
and/or functional properties. For example, different polymer fibers
can be combined by meltblowing from different spinnerets, or from a
single spinneret with different feed lines.
[0109] The meltblown nonwoven is thermally bonded to obtain a
nonwoven fabric. As known in the art, such thermal bonding can be
carried out in a manner such that the basic fiber structure of the
nonwoven is maintained at least in part. Thus, heat is applied to
an extent that the fibers may not be completely molten, but only
softened, such that binding sites are created throughout the
nonwoven fabric. Preferably, the basic nonwoven structure is
maintained in the thermal bonding step at least in portions of the
nonwoven fabric, especially in the interior.
[0110] In another embodiment, the thermal bonding is carried out by
calendering. In this standard method, a nonwoven is passed through
a pair of calender rolls, which are typically heated. The
conditions of the calendering step are adjusted such that only a
partial melting of fibers occurs, such that the nonwoven is
thermally bonded to a desired extent. The amount of bonding and
bonding strength can be adjusted for example by modifying the speed
of the calender rolls, the pressure applied, the distance between
the roller nips and the temperature applied. Thereby, it is
possible to obtain a degree of thermal bonding such that a desired
mechanical strength is obtained, whereby the basic fiber structure,
especially in the core of the nonwoven, can essentially be
maintained, or at least maintained to a desired degree. Calendering
can be carried out over the total surface of the nonwoven, or parts
thereof, when the roller surface is patterned. According to the
invention, calendering is preferred for thermal bonding, because
the mechanical strength of the nonwoven fabric can be increased,
whilst the fiber structure of the nonwoven can essentially be
maintained.
[0111] Preferably, the nonwoven fabric of the present invention
comprises a tuft-backing containing the polymeric fibers according
to the invention.
[0112] Preferably, the nonwoven fabric of the present invention
comprises a tuft-backing containing a fiber composition comprising
at least one of the polymeric fiber according to the invention and
at least one of the fiber which is selected from: [0113] fibers
having different denier values compared to the polymeric fiber
according to the invention, [0114] fibers having different shapes
compared to the polymeric fiber according to the invention.
[0115] An aspect of the invention is the use of the polymeric
fibers as defined above for the preparation of a nonwoven
fabric.
[0116] A method for the preparation of a nonwoven fabric, wherein
fibers are employed comprising at least one hollow polymeric fiber
according to the invention or a a fiber composition according to
the invention.
[0117] Preferably, the nonwoven fabric is prepared by melt or
solution spinning of the fibers through a spinneret comprising a
pattern of orifices, wherein one single fiber is formed by passing
the polymer melt though an arrangement of four slots, wherein each
slot of the four slots forming one fiber has a shape that resembles
an acute angle, or essentially right angle with straight or concave
legs, preferably each of the four slots has the form of an arrow
tip.
[0118] Preferably, the nonwoven fabric is prepared by melt or
solution spinning of the fibers through a spinneret comprising a
pattern of orifices, wherein one single fiber is formed by passing
the polymer melt though an arrangement of four slots, wherein each
slot of the four slots forming one fiber has a shape that resembles
an acute angle, or essentially right angle with straight or concave
legs, preferably each of the four slots has the form of an arrow
tip, wherein the fibers exiting the spinneret are subjected to a
one step drawing process.
[0119] A further aspect of the invention is the preparation of a
tufted nonwoven fabric, wherein the fibers for tufts in tuft
backing comprise at least one hollow polymeric fiber according to
the invention.
[0120] Another aspect of the invention is a tufted nonwoven fabric
prepared by the described method.
[0121] Another aspect of the invention is the use of a tufted
nonwoven fabric according to the invention and as defined above as
carpet backing for the preparation of carpet.
[0122] The use of a tufted nonwoven fabric according to the
invention and as defined above as carpet backing for the
manufacture of carpet, wherein the hollow polymeric fibers
according to the invention are selected from polyesters and/or
polyamides is preferred.
[0123] In one preferred embodiment, the polymeric fibers as defined
above can be used for filters and carpets, in particular carpet
tiles, wall-to-wall carpets, door mats, throw-in mats, shoe carpets
etc. wherein automotive tuft carpets are preferred.
[0124] In the tuft-backing layers of fibers according to the
invention are in contact with the pile yarn and fix them to the
substrate (tuft backing). It is advantageous of the invention that
the contact area between the fibers and the pile yarn is
significantly higher than with common round fibers known from prior
art.
[0125] It is possible to arrange the fibers according to the
invention in the tuft backing that the contact angle between the
fiber and the yarn loop (pile yarn) is preferably 20 to 90.degree.,
in particular 40 to 90.degree., especially 60 to 90.degree..
[0126] A special embodiment of the invention is the use of the
polymeric fiber according to the invention as carpet backing and
filter.
[0127] A further special embodiment of the invention is a polymer
fiber composition comprising at least two different polymer fibers,
wherein at least one of the fibers is a polymeric fiber according
to the invention as defined above. The afore-mentioned definitions
of suitable and preferred fibers according to the invention are
fully referred to here.
[0128] The at least two different polymer fibers differ in at least
one of the following properties: [0129] shape of the sectional
area, [0130] titer of the fibers, [0131] chemical composition of
the fibers.
[0132] Preferred are multi-titer, single shape filaments or multi
shape filaments.
[0133] In a preferred embodiment, the at least two different
polymer fibers are prepared in a single-stage process, in
particular using one single spinneret.
[0134] A further embodiment of the invention is a fiber composition
comprising at least one of the polymeric fiber according to the
invention and defined above and at least one of the fiber which is
selected from: [0135] fibers having different denier values
compared to the polymeric fiber according to the invention and
defined above, preferably in a top-down arrangement, [0136] fibers
having different shapes compared to the polymeric fiber according
to the invention and defined above, preferably in a top-down
arrangement.
[0137] A particular embodiment is a fiber composition comprising at
least one hollow polymeric fiber comprising a tetragonal shape
sectional area, wherein: [0138] the four corner points form
essentially a square, [0139] all four edges are concave or
straight, [0140] the fiber has a cross sectional area hollowness
ranging from 12 to 25% and at least one fiber, which is different
from the at least one hollow polymeric fiber.
[0141] In particular, a fiber composition comprising at least one
hollow polymeric fiber comprising a tetragonal shape sectional
area, wherein: [0142] the four corner points form essentially a
square, [0143] all four edges are concave or straight, [0144] the
fiber has a cross sectional area hollowness ranging from 12 to 25%,
[0145] the fiber has a titer in the range of from 4 to 16 dtex,
[0146] prepared by melt or solution spinning through a spinneret
comprising a pattern of orifices, wherein one single fiber is
formed by passing the polymer melt through an arrangement of four
slots, wherein each slot of the four slots forming one fiber has a
shape that resembles an acute angle, or essentially right angle
with straight or concave legs and at least one fiber, which is
different from the at least one hollow polymeric fiber.
[0147] Especially, the fiber composition, comprising at least one
hollow polymeric fiber comprising a tetragonal shape sectional
area, wherein: [0148] the four corner points form essentially a
square, [0149] all four edges are concave or straight, [0150] the
fiber has a cross sectional area hollowness ranging from 12 to 25%
and at least one fiber, which is different from the at least one
hollow polymeric fiber, wherein at least one fiber, which is
different from the at least one hollow polymeric fiber, is
solid.
[0151] In particular, the fiber composition, comprising at least
one hollow polymeric fiber comprising a tetragonal shape sectional
area, wherein: [0152] the four corner points form essentially a
square, [0153] all four edges are concave or straight, [0154] the
fiber has a cross sectional area hollowness ranging from 12 to 25%,
[0155] the fiber has a titer in the range of from 4 to 16 dtex,
[0156] prepared by melt or solution spinning through a spinneret
comprising a pattern of orifices, wherein one single fiber is
formed by passing the polymer melt through an arrangement of four
slots, wherein each slot of the four slots forming one fiber has a
shape that resembles an acute angle, or essentially right angle
with straight or concave legs [0157] and at least one fiber, which
is different from the at least one hollow polymeric fiber, wherein
at least one fiber, which is different from the at least one hollow
polymeric fiber, is solid.
[0158] Especially, a fiber composition, comprising at least one
hollow polymeric fiber comprising a tetragonal shape sectional
area, wherein: [0159] the four corner points form essentially a
square, [0160] all four edges are concave or straight, [0161] the
fiber has a cross sectional area hollowness ranging from 12 to 25%
[0162] and at least one of the fiber which is selected from: [0163]
fibers having different denier values compared to the at least one
hollow poly-meric fiber, preferably in a top-down arrangement,
[0164] fibers having different shapes compared to the at least one
hollow polymeric fiber, preferably in a top-down arrangement.
[0165] In particular, fiber composition, comprising at least one
hollow polymeric fiber comprising a tetragonal shape sectional
area, wherein: [0166] the four corner points form essentially a
square, [0167] all four edges are concave or straight, [0168] the
fiber has a cross sectional area hollowness ranging from 12 to 25%,
[0169] the fiber has a titer in the range of from 4 to 16 dtex,
[0170] prepared by melt or solution spinning through a spinneret
comprising a pattern of orifices, wherein one single fiber is
formed by passing the polymer melt through an arrangement of four
slots, wherein each slot of the four slots forming one fiber has a
shape that resembles an acute angle, or essentially right angle
with straight or concave legs [0171] and at least one of the fiber
which is selected from: [0172] fibers having different denier
values compared to the at least one hollow polymeric fiber,
preferably in a top-down arrangement, [0173] fibers having
different shapes compared to the at least one hollow polymeric
fiber, preferably in a top-down arrangement.
[0174] The invention is described in more detail in the following
examples.
EXAMPLE 1
[0175] A polyester spunbound fabric (nonwoven fabric) is produced.
A special spinneret is used that contains different fiber shapes
including square hollow polymeric fiber according to the invention
and a metering plate to feed molten polymer to each orifice. The
capillary is designated with 4 pieces of each slot in 0.12 mm width
and 0.6 mm length and outer diameter 0.99 mm. This yields a good
squareness and up to 18% hollowness. A tuft backing is produced by
web formation using the obtained fibers, wherein 30% of square
hollow fibers are laid vertically right in cross-section. The
achieved total surface contact is 40 to 50% higher compared to
round-solid filaments.
EXAMPLE 2
[0176] A polyester spunbound fabric (nonwoven fabric) is produced.
A special spinneret is used that contains different fiber shapes
including square hollow polymeric fiber according to the invention
and a metering plate to feed molten polymer to each orifice. The
capillary is designated with 4 pieces of each slot in 0.11 mm width
and 0.6 mm length and outer diameter 1.10 mm. This yields a good
squareness and up to 22% hollowness. A tuft backing is produced by
web formation using the obtained fibers, wherein 60% of square
hollow fibers are laid vertically right in cross-section. The
achieved total surface contact is 28.5 to 33.3% higher compared to
round-solid filaments.
[0177] While the invention has been illustrated and described in
detail in the drawings and foregoing description, such illustration
and description are to be considered illustrative or exemplary and
not restrictive. It will be understood that changes and
modifications may be made by those of ordinary skill within the
scope of the following claims. In particular, the present invention
covers further embodiments with any combination of features from
different embodiments described above and below. Additionally,
statements made herein characterizing the invention refer to an
embodiment of the invention and not necessarily all
embodiments.
[0178] The terms used in the claims should be construed to have the
broadest reasonable interpretation consistent with the foregoing
description. For example, the use of the article "a" or "the" in
introducing an element should not be interpreted as being exclusive
of a plurality of elements. Likewise, the recitation of "or" should
be interpreted as being inclusive, such that the recitation of "A
or B" is not exclusive of "A and B," unless it is clear from the
context or the foregoing description that only one of A and B is
intended. Further, the recitation of "at least one of A, B and C"
should be interpreted as one or more of a group of elements
consisting of A, B and C, and should not be interpreted as
requiring at least one of each of the listed elements A, B and C,
regardless of whether A, B and C are related as categories or
otherwise. Moreover, the recitation of "A, B and/or C" or "at least
one of A, B or C" should be interpreted as including any singular
entity from the listed elements, e.g., A, any subset from the
listed elements, e.g., A and B, or the entire list of elements A, B
and C.
* * * * *