U.S. patent application number 11/839407 was filed with the patent office on 2008-02-21 for adhesive core chenille yarns and fabrics and materials formed therefrom.
This patent application is currently assigned to FIBER INNOVATION TECHNOLOGY, INC.. Invention is credited to Jeffrey S. Dugan, Garland Earley, Frank O. Harris, Gerald T. Keep.
Application Number | 20080040906 11/839407 |
Document ID | / |
Family ID | 39083112 |
Filed Date | 2008-02-21 |
United States Patent
Application |
20080040906 |
Kind Code |
A1 |
Earley; Garland ; et
al. |
February 21, 2008 |
ADHESIVE CORE CHENILLE YARNS AND FABRICS AND MATERIALS FORMED
THEREFROM
Abstract
The present invention is directed to chenille yarns, fabrics
prepared therefrom, and items formed therewith. The chenille yarns
comprise an adhesive component that is incorporated into the yarn
is such a way that the yarns, and the fabrics made therefrom,
exhibit excellent physical characteristics, particularly abrasion
resistance.
Inventors: |
Earley; Garland;
(Weaverville, NC) ; Harris; Frank O.;
(Rogersville, TN) ; Dugan; Jeffrey S.; (Erwin,
TN) ; Keep; Gerald T.; (Kingsport, TN) |
Correspondence
Address: |
ALSTON & BIRD LLP
BANK OF AMERICA PLAZA
101 SOUTH TRYON STREET, SUITE 4000
CHARLOTTE
NC
28280-4000
US
|
Assignee: |
FIBER INNOVATION TECHNOLOGY,
INC.
|
Family ID: |
39083112 |
Appl. No.: |
11/839407 |
Filed: |
August 15, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11464633 |
Aug 15, 2006 |
|
|
|
11839407 |
Aug 15, 2007 |
|
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Current U.S.
Class: |
28/144 ; 139/395;
57/203; 57/24 |
Current CPC
Class: |
D02G 3/42 20130101 |
Class at
Publication: |
028/144 ;
139/395; 057/203; 057/024 |
International
Class: |
D02G 3/42 20060101
D02G003/42; D03D 23/00 20060101 D03D023/00 |
Claims
1. A chenille yarn comprising a first core yarn, a second core
yarn, a plurality of effect yarn segments positionally maintained
by and extending radially from the core yarns, and an adhesive
polymer blend adhering at least a portion of the effect yarn
segments to at least one of the first and second core yarn, wherein
the polymer blend is formed of a first blend component and a second
blend component, the first blend component comprising at least one
polymer having a first molecular weight, and the second blend
component comprising at least one compound having a second
molecular weight that is less than the first molecular weight of
the at least one polymer of the first blend component, wherein the
polymer blend substantially wets out a surface at a flow activating
temperature without requiring the application of pressure.
2. The chenille yarn of claim 1, wherein the first molecular weight
of the at least one polymer of the first blend component is
sufficiently high to prevent the substantial wet out of the at
least one polymer of the first blend component at the activating
temperature without the application of pressure.
3. The chenille yarn of claim 2, wherein the second molecular
weight of the at least one compound of the second blend component
is sufficiently low so that the at least one compound of the second
blend component exhibits sufficiently high molecular mobility to
prevent processing of the at least one compound of the second blend
component alone.
4. The chenille yarn of claim 1, wherein the polymer blend
substantially wets out a surface at the activating temperature
without requiring the application of pressure in a time of about
two minutes or less.
5. The chenille yarn of claim 1, wherein the activating temperature
is about 75.degree. C. to about 175.degree. C.
6. The chenille yarn of claim 1, wherein the first blend component
comprises at least one polymer having a molecular weight that is at
least about three times higher than the molecular weight of the at
least one compound of the second blend component.
7. The chenille yarn of claim 1, wherein the first blend component
comprises at least one polymer having a molecular weight that is at
least about five times higher than the molecular weight of the at
least one compound of the second blend component.
8. The chenille yarn of claim 1, wherein the first blend component
comprises at least one polymer having a first melt flow rate, and
the second blend component comprises at least one compound having a
second melt flow rate that is greater than the first melt flow
rate.
9. The chenille yarn of claim 1, wherein the first blend component
comprises at least one polymer having a first melt flow rate, and
the second blend component comprises at least one compound having a
second melt flow rate that is at least about five times greater
than the first melt flow rate.
10. The chenille yarn of claim 1, wherein the polymer blend
comprises at least one polymer selected from the group consisting
of polyolefins, polyesters, acrylics, polyamides, elastomeric
polymers, polyacrylonitrile, acetals, fluoropolymers, epoxies,
phenoxies, vinyl alcohol polymers, polyesterimides, polyhydroxyl
alkanoates (PHA), polysulfone, polyetheretherketone, cellulose
acetate, rayons, biopolymers, polyurethanes, hot melt adhesives,
copolymers thereof, terpolymers thereof, ionomers thereof, and
combinations thereof.
11. The chenille yarn of claim 1, wherein said polymer blend
comprises at least one elastomeric polymer.
12. The chenille yarn of claim 1, wherein the at least one compound
of the second blend component comprises a substantially crystalline
or semicrystalline polymer.
13. The chenille yarn of claim 12, wherein the first blend
component comprises at least one polymer having a glass transition
temperature (Tg) and wherein the substantially crystalline or
semicrystalline polymer has a melting point that is greater than
the Tg of the at least one polymer of the first blend
component.
14. The chenille yarn of claim 13, wherein the at least one polymer
having the glass transition temperature (Tg) is a phenoxy
compound.
15. The chenille yarn of claim 14, wherein the substantially
crystalline or semicrystalline polymer is a plasticizer.
16. The chenille yarn of claim 15, wherein the substantially
crystalline or semicrystalline polymer plasticizer has a molecular
weight that is less than the molecular weight of the phenoxy and
has a melting point that is greater than the Tg of the phenoxy
compound.
17. The chenille yarn of claim 1, wherein at least one of the first
and second blend components comprises a functionalized polymer.
18. The chenille yarn of claim 1, wherein at least one of the first
and second blend components comprises a polyolefin.
19. The chenille yarn of claim 18, wherein both of the first and
the second blend components comprise a polyolefin.
20. The chenille yarn of claim 18, wherein the polyolefin is
selected from the group consisting of polypropylene, polyethylene,
polybutylene, copolymers thereof, terpolymers thereof, and
combinations thereof.
21. The chenille yarn of claim 18, wherein the polyolefin is
functionalized.
22. The chenille yarn of claim 18, wherein the polyolefin is
elastomeric.
23. The chenille yarn of claim 18, wherein the polyolefin is
functionalized by reaction with at least one unsaturated anhydride,
unsaturated acid or unsaturated ester.
24. The chenille yarn of claim 18, wherein the polyolefin is
modified by reaction with at least one unsaturated anhydride,
unsaturated acid or unsaturated ester selected from the group
consisting of maleic anhydride, citraconic anhydride, itaconic
anhydride, glutaconic anhydride, 2,3-dimethylmaleic anhydride,
maleic acid, fumaric acid, citraconic acid, itaconic acid,
mesaconic acid, glutaconic acid, acrylic acid, methacrylic acid,
crotonic acid, 2-pentenoic acid, 2-methyl-2-pentenoic acid,
dimethyl malcate, diethyl maleatc, di-n-propyl malcate, diisopropyl
maleate, dimethyl fumarate, diethyl fumarate, di-n-propyl fumarate,
di-isopropyl maleate, dimethyl itaconate, methyl acrylate, ethyl
acrylate, methyl methacrylate, ethyl methacrylate, methyl
crotonate, and ethyl crotonate.
25. The chenille yarn of claim 18, wherein the polyolefin comprises
a maleic anhydride modified polyolefin.
26. The chenille yarn of claim 18, wherein at least one of the
first and second blend components comprises a maleic anhydride
modified polyolefin, and the second component comprises a
substantially crystalline polyolefin.
27. The chenille yarn of claim 1, wherein the polymer blend
comprises a coating on at least a portion of at least one of the
core yarns.
28. The chenille yarn of claim 1, wherein at least one of the core
yarns comprises a multicomponent fiber, and wherein the polymer
blend comprises at least one component of the multicomponent
fiber.
29. The chenille yarn of claim 28, wherein the multicomponent fiber
comprises a core-sheath fiber, and wherein the polymer blend
comprises the sheath.
30. The chenille yarn of claim 1, wherein at least one of the core
yarns comprises a material selected from the group consisting of
polyamides, polyamines, polyimides, polyacrylics, polycarbonates,
polydienes, polyepoxides, polyesters, polyethers,
polyfluorocarbons, polyolefins, polyphenylenes, silicon containing
polymers, polyurethanes, polyvinyls, polyacetals, polyarylates, and
copolymers thereof, terpolymers thereof, and combinations
thereof.
31. A fabric comprising a chenille yarn according to claim 1.
32. A chenille yarn comprising a first core yarn, a second core
yarn, and a plurality of effect yarn segments positionally
maintained by and extending radially from the core yarns, wherein
at least one of the first and second core yarns comprises a
continuous sheath/core filament, the sheath comprising an adhesive
component.
33. The chenille yarn of claim 32, wherein the adhesive component
comprises a polymer blend formed of a first blend component and a
second blend component, the first blend component comprising at
least one polymer having a first molecular weight, and the second
blend component comprising at least one compound having a second
molecular weight that is less than the first molecular weight of
the at least one polymer of the first blend component, wherein the
polymer blend substantially wets out a surface at a flow activating
temperature without requiring the application of pressure.
34. The chenille yarn of claim 33, wherein the first molecular
weight of the at least one polymer of the first blend component is
sufficiently high to prevent the substantial wet out of the at
least one polymer of the first blend component at the activating
temperature without the application of pressure.
35. The chenille yarn of claim 34, wherein the second molecular
weight of the at least one compound of the second blend component
is sufficiently low so that the at least one compound of the second
blend component exhibits sufficiently high molecular mobility to
prevent processing of the at least one compound of the second blend
component alone.
36. The chenille yarn of claim 33, wherein the adhesive comprises a
blend of a polyolefin and a paraffin wax.
37. The chenille yarn of claim 32, wherein the adhesive comprises
at least one maleic anhydride modified polymer.
38. The chenille yarn of claim 32 wherein the adhesive comprises at
least one polyethylene oxide.
39. The chenille yarn of claim 32, wherein the adhesive comprises
at least one polar, thermoplastic polymer having a melting
temperature of less than 200.degree. C.
40. The chenille yarn of claim 32, wherein the adhesive comprises a
polymer blend capable of substantially wetting out a surface at a
flow activating temperature without requiring the application of
pressure, the polymer blend further having blocking resistance
properties, the polymer blend comprising at least one polymer
having a first molecular weight and a glass transition temperature
(Tg), and a substantially crystalline compound having a second
molecular weight that is less than the first molecular weight of
the at least one polymer and having a melting point that is greater
than the Tg of the at least one polymer.
41. The chenille yarn of claim 32, wherein the adhesive comprises a
polymer blend capable of substantially wetting out a surface at a
flow activating temperature without requiring the application of
pressure, the polymer blend further having blocking resistance
properties, the polymer blend comprising a phenoxy having a first
molecular weight and a glass transition temperature (Tg), and a
substantially crystalline plasticizer having a second molecular
weight that is less than the first molecular weight of the phenoxy
and having a melting point that is greater than the Tg of the
phenoxy.
42. The chenille yarn of claim 32, wherein the adhesive comprises a
polymer blend formed of a first blend component and a second blend
component, the first blend component comprising at least one
polymer having a first molecular weight, and the second blend
component comprising at least one compound having a second
molecular weight, wherein the first molecular weight of the at
least one polymer of the first blend component is at least about
three times higher than the molecular weight of the at least one
compound of the second blend component, and wherein the polymer
blend substantially wets out a surface without requiring the
application of pressure at a temperature in the range of about
100.degree. C. to about 150.degree. C.
43. The chenille yarn of claim 32, wherein the adhesive comprises a
polymer blend formed of a first blend component and a second blend
component, the first blend component comprising at least one
elastomeric polymer, and the second blend component comprising a
substantially crystalline or semicrystalline polymer.
44. The chenille yarn of claim 32, wherein the adhesive comprises
metal particles.
45. The chenille yarn of claim 32, wherein, a fabric formed using
the chenille yarn exhibits an abrasion resistance measured in
double strokes according to the ASTM D-4157 abrasion test of at
least about 50,000 double strokes.
46. A fabric comprising a chenille yarn according to claim 32.
47. A product of manufacture comprising a fabric according to claim
46.
48. A fabric formed using a chenille yarn, the fabric exhibiting an
abrasion resistance measured in double strokes according to the
ASTM D-4157 abrasion test of at least about 50,000 double strokes,
wherein the chenille yarn comprises a first core yarn, a second
core yarn, a plurality of effect yarn segments positionally
maintained by and extending radially from the core yarns, and an
adhesive component adhering at least a portion of the effect yarn
segments to at least one of the first and second core yarn.
49. The fabric of claim 48, wherein the fabric formed using the
chenille yarn exhibits an abrasion resistance of at least about
60,000 double strokes.
50. The fabric of claim 48, wherein the fabric formed using the
chenille yarn exhibits an abrasion resistance of at least about
70,000 double strokes.
51. The fabric of claim 48, wherein the fabric formed using the
chenille yarn exhibits an abrasion resistance of at least about
80,000 double strokes.
52. The fabric of claim 48, wherein the fabric formed using the
chenille yarn exhibits an abrasion resistance of at least about
90,000 double strokes.
53. The fabric of claim 48, wherein the fabric formed using the
chenille yarn exhibits an abrasion resistance of at least about
100,000 double strokes.
54. The fabric of claim 48, wherein the chenille yarn has a weight
of 1250 yards/pound and the fabric has a weight of 13.5 ounces per
linear yard, has 20 warp ends per inch, having 13.5 picks per inch,
and has a 2 ounce per linear yard acrylic latex backing applied
thereto,
55. The fabric of claim 48, wherein the adhesive component
comprises a coating on at least a portion of at least one of the
core yarns.
56. The fabric of claim 48, wherein at least one of the core yarns
comprises a multicomponent fiber, and wherein the adhesive
component comprises at least one component of the multicomponent
fiber.
57. The fabric of claim 56, wherein the multicomponent fiber
comprises a core-sheath fiber, and wherein the adhesive component
comprises the sheath.
58. The fabric of claim 48, wherein at least one of the core yarns
comprises a material selected from the group consisting of
polyamides, polyamines, polyimides, polyacrylics, polycarbonates,
polydienes, polyepoxides, polyesters, polyethers,
polyfluorocarbons, polyolefins, polyphenylenes, silicon containing
polymers, polyurethanes, polyvinyls, polyacetals, polyarylates, and
copolymers thereof, terpolymers thereof, and combinations
thereof.
59. The fabric of claim 48, wherein the adhesive comprises a
polymer blend formed of a first blend component and a second blend
component, the first blend component comprising at least one
polymer having a first molecular weight, and the second blend
component comprising at least one compound having a second
molecular weight that is less than the first molecular weight of
the at least one polymer of the first blend component, wherein the
polymer blend is capable of substantially wetting out a surface at
a flow activating temperature without requiring the application of
pressure.
60. The fabric of claim 59, wherein the first molecular weight of
the at least one polymer of the first blend component is
sufficiently high to prevent the substantial wet out of the at
least one polymer of the first blend component at the activating
temperature without the application of pressure.
61. The fabric of claim 60, wherein the second molecular weight of
the at least one compound of the second blend component is
sufficiently low so that the at least one compound of the second
blend component exhibits sufficiently high molecular mobility to
substantially prevent processing of the at least one compound of
the second blend component alone.
62. The fabric of claim 48, wherein the adhesive comprises at least
one maleic anhydride modified polymer.
63. The fabric of claim 48, wherein the adhesive comprises at least
one polyethylene oxide.
64. The fabric of claim 48, wherein the adhesive comprises at least
one polar, thermoplastic polymer having a melting temperature of
less than 200.degree. C.
65. The fabric of claim 48, wherein the adhesive comprises a
polymer blend formed of a first blend component and a second blend
component, the first blend component comprising at least one
polymer having a first molecular weight, and the second blend
component comprising at least one compound having a second
molecular weight, wherein the first molecular weight of the at
least one polymer of the first blend component is at least about
three times higher than the molecular weight of the at least one
compound of the second blend component, and wherein the polymer
blend substantially wets out a surface without requiring the
application of pressure at a temperature in the range of about
100.degree. C. to about 150.degree. C.
66. The fabric of claim 48, wherein the adhesive comprises a
polymer blend formed of a first blend component and a second blend
component, the first blend component comprising at least one
elastomeric polymer, and the second blend component comprising a
substantially crystalline or semicrystalline polymer.
67. The fabric of claim 48, wherein the adhesive comprises metal
particles.
68. A method of preparing a pre-bonded chenille yarn comprising:
feeding at least two core yarns and an effect yarn into a chenille
machine, wherein at least one of the core yarns comprises
continuous sheath/core filament, the sheath comprising an adhesive;
entangling the at least two core yarns and the effect yarn in the
chenille machine; removing from the chenille machine a non-bonded
chenille yarn having a plurality of segments of the effect yarn
extending radially from the at least two core yarns of the chenille
yarn; feeding the non-bonded chenille yarn into an adhesive
activation chamber; and heating the non-bonded chenille yarn
sufficiently to activate the adhesive and adhesively bond the
effect yarn to the core yarns, thereby forming a pre-bonded
chenille yarn.
69. The method of claim 68, wherein the adhesion activation chamber
comprises a continuous autoclave apparatus.
70. The method of claim 68, wherein the adhesive comprises metal
particles, and wherein the adhesion activation chamber comprises an
apparatus generating microwave radiation.
71. The method of claim 68, wherein the adhesive comprises a blend
of a polyolefin and a paraffin wax.
72. The method of claim 68, wherein the adhesive comprises at least
one maleic anhydride modified polymer.
73. The method of claim 68 wherein the adhesive comprises at least
one polyethylene oxide.
74. The method of claim 68, wherein the adhesive comprises a
polymer blend formed of a first blend component and a second blend
component, the first blend component comprising at least one
polymer having a first molecular weight, and the second blend
component comprising at least one compound having a second
molecular weight that is less than the first molecular weight of
the at least one polymer of the first blend component, wherein the
polymer blend substantially wets out a surface at a flow activating
temperature without requiring the application of pressure.
75. The chenille yarn of claim 74, wherein the first molecular
weight of the at least one polymer of the first blend component is
sufficiently high to prevent the substantial wet out of the at
least one polymer of the first blend component at the activating
temperature without the application of pressure.
76. The chenille yarn of claim 75, wherein the second molecular
weight of the at least one compound of the second blend component
is sufficiently low so that the at least one compound of the second
blend component exhibits sufficiently high molecular mobility to
prevent processing of the at least one compound of the second blend
component alone.
77. A method of air jet weaving a chenille fabric comprising
feeding a pre-bonded chenille yarn prepared according to claim 68
into an air jet weaving apparatus.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a continuation-in-part of U.S.
patent application Ser. No. 11/464,633, filed Aug. 15, 2006, which
is incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
[0002] The present invention relates to chenille fibers and yarns.
More particularly, the invention relates to chenille fibers and
yarns having cores formed of an adhesive component.
BACKGROUND OF THE INVENTION
[0003] Chenille is commonly understood to be a yarn formed of short
lengths of spun yarn or filament (known as pile, or pile yarn, or
effect yarn) held together by two core filaments that are tightly
twisted and typically formed of a fine, strong yarn. Chenille yarn
has been produced commercially for many years and continues to gain
in popularity in light of its rich yet soft texture that provides a
pleasing and desirable feel. Chenille yarn can be difficult to
manufacture because of the great care required in its production to
ensure pile completeness (or lack of missing pile) and sufficient
strength-to-bulk relationship.
[0004] Chenille yarn is used in fabrics to form a variety of
products where a luxurious effect is desired. The breadth of
application of chenille fabrics has traditionally been limited,
though, by its inherent delicate nature. The pile that gives
chenille its velvety feel is typically maintained in the yarn by
friction applied by the twisted core yarns, and the pile is thus
subject to removal by any force sufficient to overcome the friction
supplied by the core yarns. This ability to resist withdrawal of
the pile from the chenille yarn is commonly known as abrasion
resistance. Low abrasion resistance has limited the use of known
chenille yarns in many products where the richness of chenille is
desired, such as commercial and residential upholstery fabrics,
automotive fabrics, and other products where frequent use limits
the lifespan of the product because of pile loss.
[0005] Attempts have been made to improve the abrasion resistance
and to decrease the amount of pile loss associated with chenille
yarns. In particular, adhesives have recently been used to secure
pile or effect yarns to the chenille yarn core. For example, U.S.
Pat. No. 5,651,168 discloses chenille yarns formed using a
low-melting binder filament as one or more of the core filaments of
the chenille yarn. After formation, the yarn is heat-set to melt
the low-melting binder filament and thus adhesively secure the pile
or effect yarns to the core. Such attempts at increasing abrasion
resistance have still, however, failed to provide a chenille yarn
of sufficient quality for the demands of many commercial and
residential products. Thus, there still remains a need in the art
for chenille fibers and yarns, and fabrics made therefrom, having
improved abrasion resistance.
BRIEF SUMMARY OF THE INVENTION
[0006] The present invention provides chenille yarns comprising an
adhesive component that is incorporated into the yarn is such a way
that the yarns, and the fabrics made therefrom, exhibit excellent
physical characteristics, particularly abrasion resistance.
Accordingly, the invention provides chenille yarns, chenille
fabrics, and methods of preparing chenille yarns and fabrics.
[0007] In one aspect, the invention is directed to chenille yarns.
The yarns incorporate an adhesive component but, unlike known
chenille yarns, the adhesive component improves the physical
characteristics of the yarn far beyond what has previously been
achieved. Particularly, the adhesive leads to these properties
because of its chemical make-up and/or because of the method of
incorporating the adhesive into the overall yarn structure.
[0008] In one embodiment, a chenille yarn according to the
invention comprises a first core yarn, a second core yarn, portions
of at least one effect yarn positionally maintained by and
extending radially from the core yarns, and an adhesive component.
Multiple types of adhesives can be used according to the
invention.
[0009] In a preferred embodiment, the adhesive component comprises
a polymer blend formed of a first blend component and a second
blend component, the first blend component comprising at least one
polymer having a first molecular weight, and the second blend
component comprising at least one compound having a second
molecular weight that is less than the first molecular weight of
the at least one polymer of the first blend component.
Preferentially, the polymer blend substantially wets out a surface
at a flow activating temperature without requiring the application
of pressure. The flow activating temperature can vary according to
the invention, such as in the range of about 50.degree. C. to about
200.degree. C., which is further described below.
[0010] In addition to the above, further preferred embodiments of
the invention provide for the first molecular weight of the polymer
of the first blend component to be sufficiently high so as to
prevent its substantial wet out at the activating temperature
without the application of pressure. It is further preferred for
the second molecular weight of the compound of the second blend
component to be sufficiently low so that the compound exhibits
sufficiently high molecular mobility to prevent processing of the
compound alone (i.e., without being blended with another
compound).
[0011] In particular embodiments, the polymer blend used as the
adhesive component in the invention can exhibit further
preferential properties. For example, the polymer blend
preferentially wets out a surface at the activating temperature
without requiring the application of pressure in a time of about
two minutes or less. Further, the first blend component can
comprise at least one polymer having a molecular weight that is at
least about three times higher than the molecular weight of the
compound of the second blend component. Also, the first blend
component can comprise at least one polymer having a first melt
flow rate, and the second blend component can comprise at least one
compound having a second melt flow rate that is greater than the
first melt flow rate. In specific embodiments, the polymer blend
comprises at least one elastomeric polymer and/or a substantially
crystalline or semicrystalline polymer. The polymer blend can also
comprise a functionalized polymer. In preferred embodiments, one or
both of the blend components comprises a polyolefin. Moreover, the
polyolefin can comprise a maleic anhydride modified polyolefin.
[0012] The adhesive component can be introduced into the chenille
yarn by a variety of methods. In one embodiment, the adhesive
component is in the form of a third core yarn. In further
embodiments, the adhesive component comprises a coating on at least
a portion of at least one of the core yarns. In specific
embodiments, at least one of the core yarns comprises a
multicomponent fiber, and the adhesive component comprises at least
one component of the multicomponent fiber. For example, the
multicomponent fiber can comprises a core-sheath fiber, and the
adhesive component can comprise the sheath.
[0013] The chenille yarn can particularly be characterized by the
abrasion resistance imparted by the overall composition and
combination of the components. Particularly, the abrasion
resistance can be evaluated in terms of a specific fabric prepared
using the chenille yarn. In one embodiment, a fabric can be
prepared using a chenille yarn according to the invention having a
weight of 1250 yards/pound and be formed into a fabric having a
weight of 13.5 ounces per linear yard, having 20 warp ends per
inch, having 13.5 picks per inch, and having a 2 ounce per linear
yard acrylic latex backing applied thereto. Of course, the chenille
yarn could be formed into any number of various fabrics having
various parameters. The noted fabric parameters were simply used to
set a standard that is easily reproducible by one of skill in the
art to compare a fabric prepared using a chenille yarn to the
fabric prepared using the chenille yarn of the invention. The
fabric formed using the chenille yarn of the invention is tested
for an abrasion resistance using the method of ASTM D-4157, which
measures abrasion resistance in double strokes (or double rubs).
Thus, a competing chenille yarn could be compared to the present
chenille yarn by forming a fabric exactly as outlined above and
then subjecting the fabric to the test of ASTM D-4157 (also know as
the Wyzenbeek abrasion test).
[0014] Preferably, chenille yarns of the present invention, when
formed into a fabric, such as described above, exhibit an abrasion
resistance according to ASTM D-4157 of at least about 50,000 double
strokes. As described below, a fabric prepared as described above
using the chenille yarn of the present invention exhibited an
abrasion resistance in excess of 100,000 double strokes. Such
performance is typical of fabrics prepared using the chenille yarn
of the invention.
[0015] In a specific embodiment, the chenille yarn of the invention
comprises a first core yarn, a second core yarn, portions of at
least one effect yarn positionally maintained by and extending
radially from the core yarns, and an adhesive component. In this
embodiment, at least one of the first and second core yarns
comprises a continuous sheath/core filament, the sheath comprising
the adhesive component. It has heretofore not been possible to
provide an adhesive component into a chenille yarn as part of a
multicomponent fiber. The present invention, however, is able to
provide chenille yarns and fabrics having the exceptional physical
properties described herein, at least partially, in light of the
recognition of how to achieve this feat. The exceptional abilities
can likewise arise from the specific adhesives that used in
preparing the sheath of the multicomponent filament. In particular,
any of the adhesive systems described herein can be used in the
multicomponent fiber to achieve the results of the invention.
[0016] In a further aspect, the invention also provides a fabric
comprising a chenille yarn according to the invention. In
particular, the chenille fabric can be prepared using any of the
embodiments of chenille yarns described herein.
[0017] In still another aspect, the invention provides a variety of
products of manufacture comprising a chenille fabric according to
the invention or a chenille yarn according to the invention. Such
products of manufacture can only be prepared from chenille yarns
and fabrics in light of the increased abrasion resistance provided
according to the invention.
[0018] In yet another aspect, the invention provides methods for
preparing chenille yarns. In particular, the invention provides
methods for preparing pre-bonded chenille yarns. The lack of
stability that plagues conventional chenille yarns makes it
difficult to prepare fabrics from the yarns using high energy
methods. The present invention overcomes this problem by providing
pre-bonded chenille yarns.
[0019] In one embodiment, the method of the invention comprises
feeding at least two core yarns and an effect yarn into a chenille
machine, wherein at least one of the core yarns comprises
continuous sheath/core filament, and the sheath comprises an
adhesive. The method further comprises entangling the core yarns
and the effect yarn in the chenille machine, removing a non-bonded
chenille yarn, feeding the non-bonded chenille yarn into an
adhesive activation chamber, and heating the non-bonded chenille
yarn sufficiently to activate the adhesive and adhesively bond the
effect yarn to the core yarns, thereby forming a pre-bonded
chenille yarn. The invention provides multiple methods for
continuously heating the yarn to active the adhesive.
[0020] In light of the method of forming the pre-bonded chenille
yarns, it is also possible according to the invention to prepare
fabrics using high energy methods. For example, in one embodiment,
the invention provides a method of air jet weaving a chenille
fabric. In a preferred embodiment, the method comprises feeding a
pre-bonded chenille yarn, such as prepared according to the method
described above into an air jet weaving apparatus. By this method,
it is possible to prepare an air jet woven fabric without the loss
of substantial amounts of effect fiber (i.e., amounts that would
noticeably affect the appearance of the fabric).
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Having thus described the invention in general terms,
reference will now be made to the accompanying drawings, which are
not necessarily drawn to scale, and in which:
[0022] FIG. 1 is a cross-section illustrating a multicomponent
fiber according to one embodiment of the invention, wherein the
fiber is in a sheath/core configuration;
[0023] FIG. 2 is a cross-section illustrating another embodiment of
a sheath/core fiber according to the invention;
[0024] FIG. 3 is a cross-section illustrating yet another
embodiment of a sheath/core fiber according to the invention,
wherein the core is offset within the sheath;
[0025] FIG. 4 illustrates still another embodiment of a sheath/core
fiber according to the invention, wherein the sheath and the core
exhibit different geometries in cross-section;
[0026] FIG. 5 also illustrates another embodiment of a sheath/core
fiber according to the invention, wherein the sheath and the core
exhibit different geometries in cross section;
[0027] FIG. 6 is a cross section illustrating another embodiment of
a sheath/core fiber of the invention, wherein the sheath and core
are of similar rectangular geometry;
[0028] FIG. 7 is a cross-section of an islands-in-the-sea
embodiment of a multicomponent fiber of the invention;
[0029] FIG. 8 is cross-sectional view of a segmented, round
embodiment of a multicomponent fiber of the invention;
[0030] FIG. 9 is cross-sectional view of a segmented, multi-lobal
embodiment of a multicomponent fiber of the invention;
[0031] FIG. 10 is a schematic illustration of an exemplary process
for making a multicomponent fiber according to the invention;
[0032] FIG. 11 is a schematic illustration of one embodiment of a
process for making a chenille yarn according to the invention;
[0033] FIG. 12 is a schematic illustration of another embodiment of
a process for making a chenille yarn according to the invention;
and
[0034] FIG. 13 is a schematic illustration of one embodiment of a
process for making a chenille fabric according to the
invention.
DETAILED DESCRIPTION OF THE INVENTION
[0035] The present inventions now will be described more fully
hereinafter with reference to specific embodiments of the invention
and particularly to the various drawings provided herewith. Indeed,
the invention may be embodied in many different forms and should
not be construed as limited to the embodiments set forth herein;
rather, these embodiments are provided so that this disclosure will
satisfy applicable legal requirements. As used in the
specification, and in the appended claims, the singular forms "a",
"an", "the", include plural referents unless the context clearly
dictates otherwise.
[0036] The present invention provides chenille yarns and fabrics
made with such yarns. The invention likewise encompasses a variety
of products of manufacture that can be made using the chenille
yarns and fabrics of described herein. The present invention
surpasses chenilles known in the field by providing a level of
abrasion resistance, or effect yarn stability, heretofore unknown
in the textile arts. Thus, the present invention provides chenille
yarns and fabrics that can be used not only in conventional
applications of chenille where the soft, velvety texture is
desirable but wear is minimal, but also in applications where the
soft, velvety texture is also desirable but where high use and wear
are expected. In fact, the chenille products of the present
invention provide a level of durability and abrasion resistance
allowing for use of chenille in applications, such as automobile
upholstery, commercial and residential seating (such as chairs and
sofas), and personal use items that must withstand multiple
launderings (such as bedding and clothing). Specific examples of
heavy-duty installations where chenille fabrics having the
durability provided by the present invention may be used include
the following: upholstery in hotel rooms/suites, conference rooms,
dining area usage, 24-hour transportation terminals, 24-hour
telemarketing, 24-hour healthcare emergency rooms, 24-hour casino
gambling areas, and such public gathering places as theatres,
stadiums, lecture halls, and fast food restaurants. Of course, the
chenille products of the invention also include more conventional
chenille items, such as residential fabrics and apparel fabrics.
These more typical applications include, but are not limited to,
decorative throws, upholstery fabrics, blankets and quilts. The
fabrics of the invention are machine washable or dry cleanable,
unlike conventional chenille fabrics.
[0037] As noted above, the invention also comprises a variety of
products of manufacture incorporating fabrics and yarns are
described herein. For example, the invention encompasses
automobiles incorporating upholstery comprising chenille fabric or
yarn as described herein; commercial and residential seating
(including chair and sofas) upholstered with chenille fabric or
yarn as described herein; and commercial and residential bedding
material incorporating chenille fabric or yarn as described
herein.
[0038] Increased durability and diversity of use are provided by
the invention through incorporation of an adhesive system into the
core of the chenille yarn. As pointed out above, other have tried
to improve chenille yarn durability through the used of adhesives;
however, these previous attempts have failed to achieve the
surprising and superior results of the present invention. The
improved performance provided by the present invention, in certain
embodiments, arises from the realization that an adhesive must be
delivered via a system effective to bond fibers many fiber
diameters removed from where the binder is applied, and that flow
characteristics can be increasingly important for the performance
of the end product. In the manufacture of chenille yarn, twisted
pairs of a core yarn typically hold in place bundles of effect yarn
at an angle substantially perpendicular to the core yarn. A binder
applied via the core yarn advantageously has enough flow to
penetrate to a depth of dozens of fiber diameters, yet stop short
of wicking out the length of the effect yarn and so causing it to
stiffen. Thus, the present invention preferably uses binder
materials having the necessary flow and other characteristics
described herein as useful to maximize the binding of the effect
yarn without sacrificing the desirable touch and feel
characteristics of chenille materials.
[0039] In one aspect, the present invention provides a chenille
yarn. The chenille yarn comprises at least one core yarn,
preferably at least a first core yarn and a second core yarn. A
core yarn, as used herein, is understood to refer to a single fiber
or continuous filament or a plurality of fibers that are combined
to form a continuous element. Accordingly, the chenille yarns of
the present invention also comprise at least one effect yarn
positionally maintained by and extending radially from the core
yarns. The effect yarn can generally comprise any material
typically useful in the textile fields, as more fully described
below. While the core yarns can be continuous, the effect yarns are
preferably of finite length. The chenille yarns of the invention
also comprise an adhesive component. In specific embodiments, the
core yarns are twisted together with one or more effect yarn
positioned therebetween and trapped by the core yarns. The adhesive
component then strengthens the entrapment of the effect yarn by
binding the effect yarn to the core yarn.
[0040] The chenille yarns of the present invention are
characterized by the improved properties exhibited by the yarns and
the materials made therewith. In particular, the chenille yarns of
the invention provide chenille fabrics having improved abrasion
resistance. Abrasion is generally understood to refer to the
surface wear of a fabric caused by rubbing and contact with another
fabric. In relation to chenille fabrics, abrasion often manifests
in the form of loss of effect yarns, commonly referred to as
"balding." Thus, abrasion resistance, as used herein, can refer to
the resistance to loss of effect yarn.
[0041] Abrasion resistance can specifically be determined using the
method of ASTM D4157-02 from the American Society of Testing and
Materials, which method is also known as the Wyzenbeek abrasion
test or the "double rub" test. According to ASTM D4157-02, a
Wyzenbeek machine is used, allowing samples of the test fabric to
be pulled tight in a frame and held stationary. Individual test
specimens cut from the warp and weft direction are then rubbed back
and forth using a specified abradant. One cycle is counted as a rub
across the fabric sample and then another rub back across the
sample to the starting position (i.e., a double rub). The number of
double rub cycles achieved before two yarn breaks occur, or
noticeable wear is observed, is recorded as the fabric's abrasion
rating. Thus, the abrasion resistance of a material is described in
terms of the number of double rubs before failure is achieved under
the Wyzenbeek abrasion test.
[0042] Chenille fabrics have typically been plagued by low double
rub values. Known fabrics formed of conventional chenille yarns
have double rub values in the range of about 5,000 to about 6,000.
Efforts to improve this number have included the use of specific
weaving techniques (such as the use of more filling yarns or slower
loom speeds) and the use of highly bonded backing materials. Such
efforts have failed to significantly improve abrasion resistance
and/or have detrimentally affected the aesthetic properties of the
chenille fabric. Even known attempts at using adhesives have failed
to provide the results of the present invention reaching
performance only in the range of about 15,000 double rubs without
the addition of a latex backing material.
[0043] Fabrics prepared using the chenille yarns of the present
invention, however, exhibit abrasion resistance that is far
superior to the abrasion resistance previously known in the field.
Example 1 provides a comparison between a chenille fabric of the
invention and a chenille fabric known in the art. The chenille
fabric known in the art required a backing material to provide any
reasonable degree of abrasion resistance. Thus, to be consistent in
the evaluation, the inventive fabric also included a backing
material. However, the fabrics according to the present invention
prepared with the chenille yarn described herein can be prepared
without a backing material. Thus, the invention also encompasses
chenille yarns without a backing attached thereto.
[0044] In specific embodiments, a fabric comprising the chenille
yarn of the present invention exhibits an abrasion resistance
according to ASTM D4157-02 of at least about 50,000 double rubs.
Preferably, a fabric comprising the chenille yarn of the present
invention exhibits an abrasion resistance according to ASTM
D4157-02 of at least about 55,000 double rubs, at least about
60,000 double rubs, at least about 65,000 double rubs, at least
about 70,000 double rubs, at least about 75,000 double rubs, at
least about 80,000 double rubs, at least about 85,000 double rubs,
at least about 90,000 double rubs, or at least about 95,000 double
rubs. In one embodiment, a fabric prepared using the chenille yarn
of the invention exhibits an abrasion resistance of at least about
100,000 double rubs or that exceeds 100,000 double rubs.
[0045] The present invention also provides for further improved
properties. For example, in specific embodiments, a fabric prepared
using the inventive chenille yarn exhibits improved tenacity.
Preferably, a fabric prepared using a chenille yarn as described
herein exhibits a tenacity of at least about 60 pounds in the warp
direction. More preferably, the fabric exhibits a tenacity in the
warp direction of at least about 70 pounds, at least about 80
pounds, at least about 90 pounds, at least about 100 pounds, or at
least about 110 pounds. Any method recognized in the art as useful
in evaluating fabric tenacity can be used according to the
invention.
[0046] The inventive fabric also exhibits improved seam slippage
values. In one embodiment, the inventive fabric can withstand a
load of at least about 35 pounds in the warp direction prior to
onset of seam slippage. In further embodiments, the fabric can
withstand a load in the warp direction prior to seam slippage of at
least about 40 pounds, at least about 45 pounds, or at least about
50 pounds. Any method recognized in the art as useful in evaluating
fabric seam slippage can be used according to the invention.
[0047] Still further, the inventive fabric exhibits improved seam
strength. In one embodiment, the inventive fabric has a seam
strength in the warp direction of at least about 55 pounds. In
further embodiments, the fabric has a seam strength in the warp
direction of at least about 60 pounds, at least about 65 pounds, at
least about 70 pounds, at least about 75 pounds, at least about 80
pounds, or at least about 85 pounds. Any method recognized in the
art as useful in evaluating fabric seam strength can be used
according to the invention.
[0048] In addition to the improved properties provided by the
invention, the chenille yarns of the invention are further
characterized by the flexibility in the methods of preparation.
Specifically, the adhesive component can be incorporated into the
core yarns in a variety of ways while still achieving the desired
performance parameters. In fact, in certain embodiments where
specific adhesive systems as described herein are used, the
adhesive component can be incorporated into the core yarn using any
suitable techniques known in the art.
[0049] In one embodiment, the chenille yarn can comprise at least
two core yarns, and one of the core yarns can be formed completely
of the adhesive component. When a core yarn is comprised completely
of the adhesive component, it is preferable that the chenille yarn
comprise at least three core yarns. In such embodiments, the core
yarn comprising the adhesive can be formed of a single fiber or can
comprise a plurality of fibers, wherein each of the fibers is
formed completely of the adhesive component. As used herein, the
term "fiber" is understood to encompass fibers of finite length,
such as conventional staple fiber, as well as substantially
continuous structures, such as filaments.
[0050] Similarly, the chenille yarn can comprise at least two core
yarns wherein at least one of the core yarns is a blend of
materials, and wherein at least part of the individual core yarn
comprises the adhesive component. For example, the core yarn could
be a single fiber formed of a homogeneous blend of polymeric
materials, wherein at least a portion of the polymeric materials
making up the blend comprises the adhesive material. A plurality of
such fibers could be used to form the core yarn as well, wherein
one or more of the fibers are formed of the blend. Blended yarns
can be formed by a variety of methods, including extrusion of
different filaments from a common spinneret, by blending of pure or
blended yarns after extrusion, or by spinning yarns from mixtures
of staple fibers.
[0051] In another embodiment, the chenille yarn can comprise a core
yarn formed of a plurality of fibers wherein at least one fiber of
the yarn is formed of the adhesive component and at least one fiber
of the same yarn is formed of a polymeric component that is not the
adhesive component. The chenille yarn can comprise two or more core
yarns having such a composition. This is particularly useful in
that the precise adhesive content necessary to provide the desired
adhesive effect can be achieved (i.e., avoiding use of excess
adhesive and avoiding insufficient adhesion). Moreover, the
non-adhesive fibers remain to add to the overall strength and
structure of the chenille yarn.
[0052] In still another embodiment, the chenille yarn can comprise
at least one core yarn that is at least partially coated with the
adhesive component. In such embodiments, the core yarn can comprise
a single fiber that is at least partially coated with the adhesive.
Further, the core yarn can comprise a plurality of fibers. When a
plurality of fibers is used, the adhesive coating can be on
individual fibers of the yarn. The adhesive coating can also be
applied to the bundle of fibers as a whole, meaning that the
outermost fibers would be at least partially coated, but some
fibers forming the yarn may have no adhesive material coating.
Coating of the yarn with the adhesive component can be by any
method known in the art as useful in coating fibers or yarns, such
as spraying or dipping.
[0053] The chenille fiber can also comprise core yarns formed of
staple fibers that are combined to form a continuous yarn. In such
embodiments, the adhesive component can be used to form at least a
portion of the staple fiber used in making the core yarn. Such
yarns formed of staple fibers can be used solely as the core yarns
according to the invention or can be combined with core yarns
(without or without an adhesive component) according to any of the
remaining embodiments described herein.
[0054] In yet another embodiment, the chenille yarns can comprise
core yarns formed of multicomponent fibers. A great variety of
conformations for the multicomponent fiber of the invention are
envisioned wherein an adhesive component is co-extruded with a
different fiber-forming material that does not function as an
adhesive component according to the invention, and some of the
preferred embodiments are described below with reference to the
various Figures. Of course, the skilled artisan, with the benefit
of the present disclosure, may envision further conformations that
are in accordance with the present invention, and such further
conformations are fully encompassed herein.
[0055] The multicomponent fibers according to the invention
comprise the adhesive component in a manner such that the adhesive
component is physically available to adhesively interact with the
remaining components of the chenille yarn. Preferably, the adhesive
forms at least a portion of the outer surface of the multicomponent
fiber. Thus, any multicomponent fiber conformation is encompassed
to the extent that the adhesive comprises at least a portion of the
outer surface of the fiber.
[0056] In one particular embodiment of the invention, the
multicomponent fiber is in the form of a sheath/core fiber. FIG. 1
generally illustrates such an embodiment by showing a cross-section
of a sheath/core fiber 5 having a core 10 encapsulated by a sheath
15. Preferably, the sheath 15 extends substantially the length of
the fiber 5 and comprises an adhesive component according to the
invention. When used in forming a chenille yarn as further
described herein, the sheath is subject to a physical change, such
as melting, to perform the adhesive function. Thus, the core is at
least partially exposed. This is particularly beneficial in that a
single fiber comprising the core yarn component and the adhesive
component can be prepared and used in making the chenille yarn.
Once the adhesive component has been melted, the core remains to
provide structural integrity to the chenille yarn. In a particular
embodiment, a multicomponent fiber, as described herein, can be
combined with other core yarns that do not include an adhesive
component. Thus, the multicomponent fiber functions to provide the
adhesive and provide further structural strength to the overall
chenille yarn.
[0057] Moreover, as further described below, the present invention
provides the advantage of specific adhesives systems that allow for
optimal bonding of the chenille yarn components without making the
chenille yarn, or fabric prepared from the yarn, undesirably stiff.
Therefore, known attempts at including adhesives in chenille yarns
have unsuccessfully tried to balance the durability of the chenille
(i.e., the abrasion resistance) with the desirable feel of the
chenille (i.e., the softness and velvety touch). In order to
achieve improved durability (which still does meet the durability
of the present invention), know attempts have relied on adding a
significant quantity (i.e., an "excess") of binder polymer
available, for example, by including a full core yarn dedicated to
the binder. The unique adhesives of the present invention have
specific characteristics that overcome these difficulties, and this
aspect of the invention is further described below.
[0058] The present invention is likewise beneficial, though, in
that the reduced adhesive requirement to achieve an even better
abrasion resistance can be provided in manners, such as using
multicomponent fibers. Such fibers generally provide a much smaller
overall content of adhesive to the system, which avoids any
problems associated with undesirable stiffness, or other
undesirable aesthetic qualities. Known methods of preparing
chenille yarns cannot provide a binder as part of a multicomponent
fiber (e.g., a core/sheath fiber) because such a fiber simply would
not deliver enough adhesive to achieve the desired end
result--improved durability (e.g., abrasion resistance). As the
adhesive systems of the present invention are optimized for bonding
but do not risk stiffening problems, the present invention achieves
effective bonding with less binder polymer present. Furthermore,
the flow characteristics of the present adhesive systems allow
bonding at temperatures that are sufficiently below the softening
temperature of the binder polymer (or adhesive component) that
avoids undesirable shrinkage of the non-binder components of the
multicomponent fiber. Thus, it is only according to the present
invention that it is possible to provide an adhesive in a chenille
yarn in a content effective to provide the desired durability.
[0059] The invention encompasses multiple different embodiments of
a sheath/core fiber. As shown in FIG. 1, the core 10 is
concentrically positioned within, and encapsulated by, the sheath
15, and the core 10 comprises approximately 75% by weight of the
fiber 5. Of course, the core can comprise a greater or lesser
amount of the overall fiber weight. Further, while the core is
shown substantially centered within the sheath, such is not
required.
[0060] A sheath/core fiber, according to the invention, can also
take on a variety of cross-sectional geometries. For example, the
sheath/core fiber could have a cross-section that is a circle,
oval, triangle, rectangle, octagon, pentagon, trapezoid, or the
like. Furthermore, in cross-section, the sheath could have one
geometry while the core has a different geometry. In further
embodiments, the sheath/core fiber could also be multi-lobal.
[0061] Non-limiting examples of various sheath/core fiber
embodiments encompassed by the invention are provided in FIG. 2
through FIG. 6. FIG. 2 illustrates a sheath/core fiber 5, wherein
the core 10 is concentric to the sheath 15 encapsulating the core
10, but wherein the core 10 comprises a smaller percentage of the
overall fiber as compared to the fiber illustrated in FIG. 1. FIG.
3 illustrates a sheath/core fiber 5, wherein the core 10 is
off-center within the sheath 15. FIG. 4 illustrates a sheath/core
fiber 5, wherein the core 10 has a triangular geometry while the
sheath 15 encapsulating the core 10 has a circular geometry. FIG. 5
illustrates a sheath/core fiber 5, wherein the core 10 has a
rectangular geometry while the sheath 15 encapsulating the core 10
has a circular geometry. FIG. 6 illustrates a sheath/core fiber 5,
wherein the core 10 and the sheath 15 encapsulating the core 10
both have a rectangular geometry.
[0062] In another particular embodiment of the invention, the
multicomponent fiber is in the form of an islands-in-the-sea fiber.
According to such an embodiment, a plurality of island members is
positioned within and extending through substantially the length of
the fiber, wherein each of the island members is separated from one
another. The island members comprise a polymer useful for forming a
core yarn, as described herein, and are each encapsulated by an
outer fiber component comprising an adhesive component according to
the invention.
[0063] FIG. 7 illustrates a multicomponent fiber of the invention
according to an islands-in-the-sea embodiment. The cross-sectional
view shows a plurality of islands (10, 11, 12, 13, and 14)
encapsulated by an outer fiber component 15. The islands can each
comprise the same polymeric material or can comprise different
polymers. This embodiment is likewise beneficial in that the core
yarn can be prepared to include the core yarn components as well as
the adhesive component. Moreover, once the adhesive has been
activated, such as by melting, the inner fiber components remain to
provide structural integrity to the chenille yarn. Further, the
presence of multiple, finer, core components can actually alter the
physical characteristics of the overall chenille yarn, which can be
beneficial.
[0064] The multicomponent fiber of the invention can also take on a
number of structural configurations allowing for free dissociation
of the individual fiber components. Generally, the fiber components
are arranged so as to form distinct, unocclusive cross-sectional
segments along the length of the fiber. In one such embodiment, the
multicomponent fiber of the invention can take on a pie-wedge
arrangement, such as that illustrated in FIG. 8. The pie-wedge
fiber arrangement illustrated in FIG. 8 is a bicomponent filament 4
having eight alternating segments of triangular shaped wedges
comprising the overall "pie". The wedges comprise a first fiber
component 6 (which is formed of a material useful as a chenille
core yarn, as described herein) and a second fiber component 8
(which comprises an adhesive component, as described herein). While
the pie-wedge filament illustrated in FIG. 8 is a non-hollow fiber,
the invention also encompasses FIG. 8 comprises eight wedge
segments, it should be recognized that filaments according to the
invention can comprise more or less than eight segments.
[0065] In addition to the pie-wedge configuration illustrated in
FIG. 8, the multicomponent fiber of the invention can also take on
other segmented, splittable fiber configurations. For example, the
FIG. 9, which shows a round fiber 4 segmented into four alternating
sections, comprising a first fiber component 6 (comprising a core
yarn material) and a second fiber component 8 (comprising an
adhesive component). Description of further multicomponent fiber
construction that may be useful according to the present invention
can be found in U.S. Pat. No. 5,108,820; U.S. Pat. No. 5,336,553;
and U.S. Pat. No. 5,382,400; which are all incorporated herein by
reference.
[0066] The multicomponent fibers of the present invention are
further advantageous in that they are not limited to configuration
as conventional round fibers. Rather, the multicomponent fibers can
take on other useful shapes. Generally, any shape for a segmented
multicomponent fiber can be used so long as a fiber segment
comprising the adhesive component according to the invention is
present at the surface of the multicomponent fiber. For example,
the inventive multicomponent fiber can take on a multilobal
configuration, as illustrated in FIG. 9. Further description of
multicomponent fibers of unconventional shape that may be useful
according to the present invention can be found in U.S. Pat. No.
5,277,976; U.S. Pat. No. 5,057,368; and U.S. Pat. No. 5,069,970;
which are all incorporated herein by reference.
[0067] Regardless of the various embodiments which the
multicomponent fiber can take on (i.e., sheath/core,
islands-in-the-sea, pie/wedge, etc.), the multicomponent fiber
still comprises an adhesive component-containing material and a
separate fiber component capable of functioning as a core yarn. The
overall composition of the multicomponent fiber can vary depending
upon the application of the fiber. For example, if the
multicomponent fiber is intended to provide all of the adhesive
component, it may be desirable for the adhesive component sheath to
form a majority of the overall fiber. However, in embodiments
wherein multiple multicomponent fibers are included, it may be
desirable for the sheath to comprise only a minor part of the
overall fiber as the sum total of the sheaths in the multiple
fibers will provide sufficient adhesive and the cores of the
multicomponent fibers can provide sufficient strength to the
chenille cores.
[0068] It is possible for the multicomponent fibers of the
invention to be provided as staple fibers or other short forms.
However, the invention is particularly useful in that continuous
filaments, such as continuous sheath/core filaments, can be used as
the multicomponent fiber component of the chenille yarn. This
particularly allows for continuous processing of the chenille yarns
from the formation of the multicomponent fibers to the completion
of the chenille fabric.
[0069] The adhesive component of the fiber sheath, in particular
embodiments, comprises between about 5% by weight and about 95% by
weight of the multicomponent fiber. In further embodiments, the
adhesive component comprises about 10% by weight to about 90% by
weight of the multicomponent fiber, about 10% by weight to about
80% by weight, about 20% by weight to about 75% by weight, and
about 25% by weight to about 85% by weight of the multicomponent
fiber.
[0070] A multicomponent fiber according to the invention can be
prepared using any of the fiber formation techniques as known in
the art. An exemplary method for producing a multicomponent fiber
is illustrated in FIG. 10, which illustrates a melt spinning line
20 for producing bicomponent fibers, and which includes a pair of
extruders 22 and 24. As will be appreciated by the skilled artisan,
additional extruders may be added to increase the number of
components (for example, wherein a plurality of
temperature-regulating inner fiber components are encapsulated by
an outer fiber component in a sheath/core embodiment). Extruders 22
and 24 separately extrude an inner fiber component and an outer
fiber component. The inner fiber component is fed into extruder 22
from a hopper 26 and the outer fiber component is fed into extruder
24 from a separate hopper 28. The inner fiber component and the
outer fiber component are fed from extruders 22 and 24 through
respective conduits 30 and 32 by a melt pump (not shown) to a
spinneret 34.
[0071] The inner fiber component and the outer fiber component are
preferably matched to allow spinning of the components through a
common capillary at substantially the same temperature without
degrading one of the components. The invention, however, should not
be viewed as limited to combinations of inner fiber components and
outer fiber components with substantially similar extrusion
temperatures. Rather, the outer fiber component (e.g., an adhesive
component) may have a relatively low extrusion temperature, and the
inner fiber component (e.g., the chenille yarn core component) may
have a relatively high extrusion temperature. Temperature disparity
is only limited in that the extrusion temperature of the inner
fiber component should be sufficiently low so as to not cause
thermal degradation of the outer fiber component.
[0072] In one advantageous embodiment, polypropylene is used as the
inner fiber component. In another useful embodiment, polyamide is
used as the inner fiber component. In yet another embodiment,
polyurethane is used as the inner fiber component. Some
thermoplastic polyurethanes can be extruded at a temperature
ranging from about 160.degree. C. to about 220.degree. C. Nylon 6,
a particularly useful polyamide according to the invention, is
typically extruded at a temperature ranging from about 250.degree.
C. to about 280.degree. C. Polyethylene and polypropylene are
typically extruded at a temperature ranging from about 200.degree.
C. to about 230.degree. C.
[0073] Extrusion processes and equipment, including spinnerets, for
making multicomponent continuous filament fibers are well known and
need not be described here in detail. Generally, a spinneret
includes a housing containing a spin pack which includes a
plurality of plates stacked one on top of the other with a pattern
of openings arranged to create flow paths for directing
fiber-forming components separately through the spinneret. The
spinneret has openings or holes arranged in one or more rows. The
polymers are combined in a spinneret hole. The spinneret is
configured so that the extrudant has the desired overall fiber
cross section (e.g., round, trilobal, etc.). The spinneret openings
form a downwardly extending curtain of filaments. Such a process
and apparatus is described, for example, in U.S. Pat. No.
5,162,074, to Hills, which is incorporated herein by reference.
[0074] Following extrusion through the die, the resulting thin
fluid strands, or filaments, remain molten for some distance before
they are solidified by cooling in a surrounding fluid medium, which
may be chilled air blown through the strands (not shown). Once
solidified, the filaments are taken up on a godet or other take-up
surface. For example, in a continuous filament process as
illustrated in FIG. 10, the strands are taken up on godet rolls 36
that draw down the thin fluid streams in proportion to the speed of
the take-up godet.
[0075] The core yarns used in the chenille yarns of the invention
can be formed using a variety of materials. In most embodiments,
the core yarn can comprise any polymeric material (or mixture
thereof) that is capable of being formed into an elongated fiber.
The polymeric material used in forming the core yarn of the
chenille yarn can vary depending upon the process used in preparing
the yarn. For example, when the core yarn is formed of extruded
fibers, a melt spinning process may used to form the fibers. Thus,
the polymeric material is beneficially a melt-processable
thermoplastic polymer, or mixture of polymers. According to other
embodiments of the invention, the polymeric material can include an
elastomeric polymer, or mixture of polymers.
[0076] The polymeric material used in preparing the core yarn of
the inventive chenille yarn can comprise a polymer (or mixture of
polymers) having a variety of chain structures that include one or
more types of monomer units. In particular, a polymeric material
may comprise a linear polymer, a branched polymer (such as a star
branched polymer, a comb branched polymer, or a dendritic branched
polymer), or a mixture thereof. A polymeric material may also
comprise a homopolymer, copolymer, terpolymer, statistical
copolymer, random copolymer, alternating copolymer, periodic
copolymer, block copolymer, radial copolymer, or graft copolymer,
or a mixture thereof.
[0077] In certain embodiment, a polymeric material useful in a core
yarn for forming a chenille yarn according to the invention can be
determined based upon the melting temperature of the polymeric
material. In one particular embodiment, the core yarn comprises a
polymeric material having a melting temperature of greater than
about 80.degree. C. In other embodiments, the core yarn comprises a
polymeric material having a melting temperature of greater than
about 100.degree. C., greater than about 125.degree. C., greater
than about 130.degree. C., greater than about 140.degree. C.,
greater than about 150.degree. C., greater than about 160.degree.
C., greater than about 175.degree. C., greater than about
200.degree. C., or greater than about 220.degree. C.
[0078] By way of non-limiting example, various classes of polymers
that may be used to form a core yarn according to the invention can
include the following: polyamides, polyamines, polyimides,
polyacrylics, polycarbonates, polydienes, polyepoxides, polyesters,
polyethers, polyfluorocarbons, polyolefins, polyphenylenes, silicon
containing polymers, polyurethanes, polyvinyls, polyacetals,
polyarylates, copolymers thereof, terpolymers thereof, and mixtures
thereof. Non-limiting examples of specific polymeric materials
useful as the outer fiber component according to the present
invention include the following: Nylon 6, Nylon 6/6, Nylon 12,
polyaspartic acid, polyglutamic acid, polyacrylamide,
polyacrylonitrile, esters of methacrylic acid and acrylic acid,
polybisphenol A carbonate, polypropylene carbonate, polybutadiene,
polyisoprene, polynorbonene, polyethylene terephthalate,
polybutylene terephthalate, polytrimethylene terephthalate,
polycaprolactone, polyglycolide, polylactide, polyhydroxybutyrate,
polyhydroxyvalerate, polyethylene adipate, polybutylene adipate,
polypropylene succinate, polyethylene glycol, polybutylene glycol,
polypropylene oxide, polyoxymethylene, polytetramethylene ether,
polytetrahydrofuran, polyepichlorohydrin, urea-formaldehyde,
melamine-formaldehyde, phenol formaldehyde, polyethylene,
polypropylene, polybutylene, polybutene, polyoctene, polyphenylene
oxide, polyphenylene sulfide, polyether sulfone, polyphenylene
ether sulfone, polydimethyl siloxane, polycarbomethyl silane,
polyvinyl butyral, polyvinyl alcohol, esters and ethers of
polyvinyl alcohol, polyvinyl acetate, polystyrene,
polymethylstyrene, polyvinyl chloride, polyvinyl pyrrolidone,
polymethyl vinyl ether, polyethyl vinyl ether, polyvinyl methyl
ketone, polyethylene-co-vinyl acetate, polyethylene-co-acrylic
acid, polybutylene terephthalate-co-polyethylene terephthalate, and
polylauryllactam-block-polytetrahydrofuran. The core yarn can also
comprise natural fibers (such as cotton, linen, jute, hemp, cotton,
wool, and wood pulp), regenerated cellulosic fibers (such as
viscose rayon and cuprammonium rayon), and modified cellulosic
fibers (such as cellulose acetate). In one particular embodiment,
the core yarn comprises polyolefins, such as polypropylene.
[0079] The material used in preparing the core yarn can be chosen
based upon intrinsic factors apart from melting temperature alone.
For example, a core yarn material can be chosen based upon the
dyeability of the material so that the end product chenille can
have the desired properties. The pile or effect yarns can likewise
be chosen based upon such considerations.
[0080] The chenille core yarns preferably have an overall size
commensurate with conventional chenille yarns. In certain
embodiments, the core yarns are in the range of about 100 denier to
about 900 denier, preferably about 100 denier to about 800 denier,
more preferably about 100 denier to about 600 denier. Each core
yarn can also comprises a plurality of individual filaments. In
certain embodiments, the core yarn can comprise between 2 filaments
and about 250 filaments, preferably about 4 filaments to about 200
filaments, more preferably about 8 filaments to about 150
filaments, and more preferably about 10 filaments to about 100
filaments. Each filament is preferably less than about 20 denier,
more preferably less than about 15 denier, even more preferably
less than about 10 denier, and most preferably less than about 5
denier. Of course, in embodiments where the core yarn comprises a
single filament, the single filament would be expected to be of
greater size, such as about 20 denier to about 100 denier.
[0081] Suitable pile or effect yarns for use in the chenille yarns
of the present invention include, but are not limited to the
following: natural fibers, such as cotton, linen, jute, hemp,
cotton, wool, and wood pulp; regenerated cellulosic fibers such as
viscose rayon and cuprammonium rayon; modified cellulosic fibers,
such as cellulose acetate; and synthetic fibers such as those
described above in relation to the core yarn, especially those
derived from polypropylene, polyethylene, polyvinyl alcohol,
polyesters, polyamides, and polyacrylics. The above-mentioned pile
or effect yarns may be used alone or in combination with one
another. Multicomponent fibers comprising a blend of one or more of
the above materials may also be used if so desired. Desirably, the
pile or effect yarn comprises cotton, wool or acrylic yarns, alone
or in combination with one another.
[0082] The adhesive component of the inventive chenille yarns can
comprise any adhesive capable of forming a chenille yarn meeting
the performance standards described herein. Particularly, the
adhesive should be capable of providing abrasion resistance within
the performance ranges described above. Preferably, the adhesive
component is "activatable" or subject to "activation" by external
means. In other words, the adhesive should comprise a compound
having at least one physical or chemical property such that upon
application of activation means (e.g., heat, radiation, etc.), the
compound transitions to a state where it can effect adhesion of the
remaining components of the chenille yarn. Thus, a step of
activating an adhesive can mean subjecting the adhesive compound to
conditions such that the compound is formed into a state effective
for facilitating adhesion.
[0083] The adhesives of the invention are particularly useful in
achieving the surprising performance characteristics described
herein. Previous attempts to incorporate an adhesive into yarns
have faced the difficulty of balancing bonding strength with the
risk of stiffening the yarns and fabrics prepared with the yarns.
In other words, it has not heretofore been known how to adhesively
secure effect yarns in a chenille yarn in a manner that maximizes
the strength (and, therefore, abrasion resistance) of the yarns,
and fabrics prepared with the yarns, without sacrificing the
desirable qualities of the chenille (e.g., softness, velvety
texture, etc.). According to the present invention, the specific
compounds and combinations of compounds comprising the adhesive
component of the chenille yarn are able to achieve optimal bonding
without sacrificing any of the desired "feel" characteristics of
chenille. In particular, the adhesives of the invention have flow
characteristics allow for optimum bonding without fear of
"stiffening" of the overall chenille product. More particularly, in
specific embodiments, the present invention provides a dual-mode
adhesive that specifically relies on a combination of at least two
compounds to achieve this goal. Such combinations are described
below.
[0084] In one preferred embodiment, an adhesive useful according to
the invention can be formed of a specific blend of polymers. Such
polymer blends are particularly useful in light of their desirable
yet contradictory properties. For example, the polymer blends can
exhibit wet out properties while also providing desirable blocking
resistance (or anti-blocking) and durability properties as
well.
[0085] The properties of a polymer blend typically are not simply a
linear mixture of those of the constituent polymers, but rather the
blend properties that result are often inferior to that of a linear
prediction. For example, modifying the melt viscosity of a polymer
used in the production of hot melt adhesives by blending with
another polymer to reduce tackiness can negatively impact the
desired flow of the resultant product and render is useless for its
intended application. Conversely, blending a high melt strength
polymer with another polymer to improve flow properties can
similarly result in a product that no longer useful for its
intended purpose.
[0086] The polymer blends useful according to the present invention
can substantially or completely wet out a surface at a given
activating temperature without requiring the application of
substantial or any pressure. Stated differently, the polymer blends
of the invention are readily flowable under activating temperature
conditions without requiring the concurrent application of pressure
to promote or facilitate polymer flow. Yet, despite the ready flow
or wetting properties of the polymer blends of the invention, in
contrast to conventional flowable polymers, the polymer blends do
not exhibit substantial blocking problems.
[0087] The "wetting out" of a surface is intended to refer to the
physical contact of the activated adhesive with the surface to
which it is applied. In relation to the chenille yarns of the
invention, wetting out refers to the contact of the adhesive with
the core yarns. Reference herein to "substantially" wetting out a
surface will be readily understood by the skilled artisan and can
be assessed using known techniques. Completely wetting out the
surface would indicate that 100% of the exposed surface to be
contacted by the activated adhesive is covered by the adhesive. In
specific embodiments, substantially wetting out the surface
indicates adhesive coverage approaching 100%, including about 99%
coverage, about 98% coverage, about 97% coverage, about 96%
coverage, about 95% coverage, and about 90% coverage of the exposed
surface by the activated adhesive.
[0088] Wetting out of a surface often requires the application of
pressure to evenly distribute an adhesive material. In exemplary
embodiments of the present invention, though, the polymer blend can
substantially wet out a surface to which is has been applied
without requiring the application of substantial pressure or
completely without the application of pressure. As used herein, the
absence of "substantial pressure" refers to the application of
pressure beyond pressure associated with concomitant processing
conditions. In relation to the formation of chenille yarns, it is
preferable that wetting out can occur without addition of any
external pressure on the yarn.
[0089] In exemplary embodiments of the invention, the polymer blend
can substantially or completely wet out the surface in about one
hour or less, and can be applied in as little as a few minutes (for
example, about two minutes or less) at a selected activating
temperature. Wetting out of a substrate surface generally refers to
contact angles of less than about 90 degrees, or less than about
135 degrees.
[0090] An activating temperature according to the invention is
intended to refer to the temperature at which the adhesive
component transitions from a stable, non-flowable state (i.e., the
solid form) into a flowable state (e.g., a melt or a liquid), and
may be referred to as the flow activating temperature. The flow
activating temperature for the polymer blends can vary depending on
various factors. Preferably, the polymer blends of the invention
have an activating temperature of less than about 200.degree. C.,
less than about 175.degree. C., less than about 150.degree. C.,
less than about 125.degree. C., less than about 100.degree. C., or
less than about 75.degree. C. In specific embodiments, the flow
activating temperature ranges from about 75.degree. C. to about
175.degree. C. or from about 100.degree. C. to about 150.degree.
C., although polymer blends exhibiting substantial wetting
properties at activating temperatures outside of this range can
also be useful. The term activating temperature as used herein
refers to the temperature at which the polymer blend will flow and
does not necessarily refer to the temperature of an oven, bath, or
other heating device through which an article to which the polymer
blend is applied may be passing.
[0091] Polymer blends of the invention can be made to conform to
certain processing conditions, such as the activating temperature.
In a specific embodiment, the polymer blend can exhibit a flow
activating temperature of about 100.degree. C. Such systems can be
designed to exhibit very high flow in conditions typical to water
evaporation or steam generation, such as passing a substrate
through a low temperature drying oven (i.e., enough heat to drive
off water), or exposing the substrate to high temperature water or
steam (e.g., in dye baths, etc.). The onset of softening can be
well above 55.degree. C. so that the flow transition can be sharp
to avoid tackiness or blocking. Thus, even in embodiments where the
activating temperature is around 100.degree. C., the polymer blend
is not tacky and does not block above about 55.degree. C.
[0092] In other embodiments of the invention, the polymer blend can
exhibit a flow activating temperature of about 125.degree. C. Such
systems can be substantially inert at boiling water temperatures
yet can flow well in higher temperature conditions, such as an
autoclave. Such systems can likewise be suited for powdered
delivery to a substrate in applications for which stability in hot
water, such as in washing, is advantageous or required.
[0093] In further embodiments, the polymer blend can have an
activating temperature of about 150.degree. C. Such systems can
have higher melt strengths and accordingly can be more readily melt
spun to form a fibrous article, such as a component of a
multicomponent fiber or filament (for example, a sheath component
of a bicomponent sheath core fiber). The resultant higher viscosity
exhibited by such polymer blends can result in longer penetration
times at temperatures of less than 150.degree. C. (for example
about 125.degree. C.), but viscosity can decrease at increasing
temperatures, including temperatures approaching 150.degree. C.,
and/or using finer dispersions of the solid binder and/or more
penetrating radiant energy for faster heat-up. Such systems can be
suited for delivery via bicomponent fibers introduced into a
substrate, for example, by blending the bicomponent fibers with
other fibers.
[0094] As used herein, the term "blocking" refers to the
"stickiness" or "tackiness" that polymer products can exhibit when
exposed, either in the raw material state or after activation and
resolidification, to elevated temperatures and/or other
environmental conditions (such as humidity), during processing,
storage, and/or transportation. Blocking can be particularly
problematic in the storage and/or transportation of products formed
of readily flowable polymers that are subjected to extremes in
ambient temperature, humidity, and other conditions that can result
in undesired adhesion of the products to one another, or to other
objects. Blocking is a problem encountered in many adhesive polymer
applications and often requires the inclusion of "anti-blocking"
additives.
[0095] In contrast to many conventional flowable polymers, the
polymer blends useful in the invention exhibit block resistant (or
anti-blocking) properties without requiring the addition of
substantial amounts of anti-blocking agents. Thus, the polymer
blends are not susceptible to developing a tacky or sticky feel
when cooled from elevated temperatures, such as those used in
polymer processing or when packages or rolls are exposed to
expected extremes of temperature, humidity, and other environmental
conditions to which a polymer product can be exposed during
transportation and storage.
[0096] Blocking can be evaluated using procedures known in the art.
For example, pellets or powder can be layered several deep in an
aluminum pan, which is then placed in a convection oven at a
specified time for a specified temperature. Test conditions, such
as time, temperature, humidity, and the like, employed in analyzing
blocking properties, can be based on anticipated field use
conditions that will be experienced. The pellets are then removed
from the oven and cooled. If the pellets adhere to one another at
all, they are judged to fail by "blocking." Weight may be applied
and blocking may appear only at the bottom of a container. Long
storage times and potential humidity effects may also increase
actual blocking behavior.
[0097] Polymer blends used as an adhesive component in the present
invention preferably comprise two or more different components,
wherein at least two of the components include one or more polymers
or other compounds that differ from one another with respect to
their molecular weights. The polymer blends can comprise at least a
first blend component and a second blend component. Preferably, the
first blend component comprises one or more polymers having a first
molecular weight, and the second blend component comprises one or
more compounds (which may or may not be polymeric in nature) having
a second molecular weight that is less than the molecular weight of
the polymer of the first blend component. The respective blend
components can also be referred to as the higher molecular weight
polymer component and the lower molecular weight component. In
exemplary embodiments, the higher molecular weight blend component
can include at least one or more polymers having a molecular weight
that is at least about three times higher than the molecular weight
of at least one or more compounds of the lower molecular weight
blend component. In further embodiments, the higher molecular
weight blend component can include at least one or more polymers
having a molecular weight that is up to about five times higher
than the molecular weight of at least one or more compounds of the
lower molecular weight blend component.
[0098] Although not wishing to be bound by any theory, it is
believed that the blends take advantage of the fact that melt
strength and melt viscosity follow different functions of polymer
molecular weight distribution. The combinations of high and low
molecular materials useful in the invention can exhibit high melt
strength or elasticity as compared to the viscosity or resistance
to flow also exhibited by the blend. The resultant blends can flow
well yet can also be strong and can be spun into fibers.
[0099] In specific embodiments the molecular weight of the polymers
of the higher molecular weight blend component is such to prevent
the first blend component from substantially wetting out a surface
without the application of substantial pressure under the same
temperature conditions (i.e., flow activating temperature) under
which the overall polymer blend will substantially wet out the
surface, as discussed above. The higher molecular weight polymer(s)
can have a number average molecular weight ranging from greater
than about 6,000 to about 50,000. In specific embodiments, polymers
having even higher molecular weights can be used. In certain
embodiments, the number average molecular weight is from about
18,000 to about 30,000. The higher molecular weight polymer
component can be useful in imparting desired melt strength to the
polymer blends.
[0100] All molecular weights provided herein are provided as number
average molecular weight unless otherwise noted. Number average
molecular weight (M.sub.n) can be calculated according to the
following formula M _ n = i .times. N i .times. M i i .times. N i
##EQU1##
[0101] wherein N.sub.i is the number of polymer molecules (or the
number of moles of those molecules) having molecular weight
M.sub.i.
[0102] In various embodiments, the polymer(s) of the higher
molecular weight blend component are selected to have a molecular
weight that is sufficiently high to impart sufficient melt strength
to the blend to permit processing of the polymer blend, such as to
permit melt spinning or quenching the polymer blend. Thus, it is
possible to form a desired product, such as a fiber or fibrous
structure, including a component of a multicomponent fiber, as
described herein. Melt strength is commonly measured by die-swell
when a polymer is exuded from a capillary. The practical
manifestation is that molten streams in a spin cabinet can be
pulled without breaking, elongating to form individual fibers.
[0103] The molecular weight of the one or more compounds of the
lower molecular weight component can be selected to be sufficiently
low so that the second blend component exhibits a level of
molecular mobility sufficiently high so as to limit its usefulness
for the production of an article such as a fiber or fabric when
processed alone and without combination with another component. The
one or more compounds and/or the second blend component may, for
example, exhibit too much molecular mobility so that its usefulness
alone is limited because it may be susceptible to blocking, and/or
because it may exhibit too much creep, and/or it may have
inadequate melt strength to be processed. In various exemplary
embodiments of the invention, the one or more compounds of the
lower molecular weight blend component can have a molecular weight
of about 6,000 or less. In certain embodiments, the molecular
weight is greater than 0 to about 6,000 or greater than about 500
to about 6,000. Preferably, the one or more compounds of the lower
molecular weight blend component (without combination with another
component) cannot be spun onto a package without blocking, using
normal commercial fiber spinning operations.
[0104] Creep or cold flow of a polymer blend can be evaluated using
an accelerated test as follows. Pellets are loaded into a capillary
rheometer such is used for melt flow testing, and a specified
weight is applied (e.g. the standard 2.16 kg). The temperature is
then ramped up in gradual steps until the weighted piston begins to
compress the pellets. The temperature at which this happens is
noted. Cold flow can also be checked at ambient temperatures
periodically, (e.g., 30 days or 60 days).
[0105] In addition to the relative molecular weights of the
components of the blends, the blend components, and one or more of
the constituent polymers and/or compounds thereof, can also differ
with regard to melt flow rate (MFR), also as determined using
conventional test standards, such as ASTM method D 1238B. In
specific embodiments, the higher molecular weight polymer
component, and/or one or more of its constituent polymer(s), can
have a melt flow rate less than the melt flow rate of the lower
molecular weight component, and/or one or more of its constituent
compound(s). Stated differently, the lower molecular weight
component (and/or one or more of its constituent polymers) of the
polymer blend can have a relatively high MFR as compared to the MFR
of the higher molecular weight polymer component (and/or one or
more of its constituent compounds).
[0106] As non-limiting examples, the lower molecular weight
component (and/or one or more of its constituent compounds) can
have a melt flow rate that is at least about five times, or at
least about ten times, higher than the melt flow rate of the higher
molecular weight polymer component (and/or one or more of its
constituent polymers). In other embodiments, the higher molecular
weight polymer component (and/or one or more of its constituent
polymers) can have a melt flow rate of about 1 decigrams per minute
at a temperature of about 125.degree. C. as determined in
accordance with ASTM method D 1238B, and the lower molecular weight
component (and/or one or more of its constituent compounds) can
have a melt flow rate of about 100 decigrams per minute at a
temperature of about 125.degree. C.
[0107] The components, and/or one or more of the constituent
polymers and/or compounds thereof, of the blends of the invention
can also differ from one another with regard to melting point, as
determined using conventional test standards, such as differential
scanning calorimetry (DSC). In certain embodiments, the higher
molecular weight polymer component (and/or one or more of its
constituent polymers) can have a melting point that is higher than
the melting point of the lower molecular weight component (and/or
one or more of its constituent compounds). Thus, the lower
molecular weight component (and/or one or more of its constituent
compounds) of the polymer blend can have a relatively low melting
point as compared to the melting point of the higher molecular
weight polymer component (and/or one or more of its constituent
polymers). In specific embodiments, the higher molecular weight
polymer component (and/or one or more of its constituent polymers)
can have a melting point of at least about 10.degree. C., at least
about 20.degree. C., or at least about 50.degree. C., higher than
the melting point of the lower molecular weight component (and/or
one or more of its constituent compounds).
[0108] The melting point of the uniform polymer blend itself can
also vary, depending on various factors. In exemplary embodiments,
the melting point of the polymer blend can be within about
20.degree. C. of the targeted blend application temperature (i.e.,
the activating temperature). The polymer blends exhibit the desired
flow properties described herein despite the presence of the higher
molecular weight component, which typically does not flow until
exposed to an "activating" temperature of at least about 50.degree.
C. or more above its melting point. Suitable polymer components
useful for providing a polymer blend with a melt temperature as
described herein can include substantially crystalline polymers, as
discussed in more detail below.
[0109] The molecular weight ranges of the blend components can vary
depending on a particular application or use of the blend and can
be readily determined by the skilled artisan. In various
embodiments, the blends can be of similar portions of two materials
with fairly extreme differences in flow (due to crystallinity
and/or molecular weight) yet are compatible and provide synergistic
properties in the blend. Such synergies can be exhibited by
sufficient melt strength/viscosity for fiber formation and/or by a
flow/tack sharp profile effect as discussed herein.
[0110] The polymer components of the polymer blends can include any
of the types of polymers suitable for the formation of a particular
article, i.e., can be any of the types of polymer resins known in
the art capable of being formed into article such as fibrous
materials (including without limitation fibers, filaments, yarns,
nonwoven articles, and the like, as discussed herein). Particular
examples of polymers forming the blends useful according to the
present invention include without limitation polyolefins, including
polypropylene, polyethylene, polybutene, and polymethyl pentene;
polyamides, including nylon 6 and nylon 6,6; polyesters, including
polyethylene terephthalate (PET), polyethylene naphthalate (PEN),
polytrimethylene terephthalate (PTT), poly(1,4-cyclohexylene
dimethylene terephthalate) (PCT), glycol-modified polyethylene
terephthalate (PETG), and aliphatic polyesters such as polylactic
acid (PLA); acrylics; thermoplastic elastomers; polyacrylonitrile;
acetals; fluoropolymers; epoxies; phenoxies; vinyl alcohol
polymers; polyesterimides; polyhydroxyl alkanoates (PHA);
polysulfone; polyetheretherketone; cellulose acetate and rayons;
polyurethanes; hot melt adhesives; and the like, as well as
copolymers, terpolymers, and ionomers of these and other suitable
polymers, and combinations thereof. Polyolefins can be particularly
advantageous in various embodiments. Bio-based polymers which can
be biodegradable made from PLA and PHA can also be useful in
various embodiments.
[0111] Hot melt adhesives can particularly be useful in various
embodiments. Hot melt adhesives are typically thermoplastic
polymers that are solid at room temperature and liquid at elevated
temperatures, for example, solid at temperatures below 180.degree.
F. and low viscosity fluids above 180.degree. F. Hot melt adhesives
set to a bond on cooling. Hot melt adhesives can include without
limitation paraffins, waxes, polyolefins, polyvinyl acetate
polyamides, ethylene vinyl acetate (EVA) copolymers,
styreneisoprene-styrene (SIS) copolymers; styrene-butadiene-styrene
(SBS) copolymers; ethylene ethyl acrylate copolymers (EEA);
polyurethane reactive (PUR), and the like, and combinations
thereof.
[0112] Thermoplastic elastomers as known in the art can also be
useful in various embodiments. Exemplary elastomers include without
limitation polyurethane elastomeric materials; polyamide
elastomeric materials; polyester elastomers; polyetherester
elastomeric; polyetheramide elastomeric materials; polyolefin
elastomers; elastomeric styrene block copolmyers, including diblock
and triblock copolymers based on polystyrene (S) and unsaturated or
fully hydrogenated rubber blocks, which can consist of butadiene
(B), isoprene (I), or the hydrogenated version, ethylene-butylene
(EB); and the like and combinations thereof.
[0113] Functionalized polymers can also be useful as one or more of
the components of the blends. The functionality can be selected to
provide a desired thermodynamic attractive force between the
polymer blend and the target substrate to which the blend is
applied, such as a natural fiber. This in turn can improve wet out
of the polymer blend.
[0114] The polymers can be functionalized as known in the art to
impart a desired property thereto, such as a functional group to
improve wet out and/or adhesion properties of the polymer component
and/or the resultant polymer blend. Exemplary functionally modified
polymers useful in various embodiments can include, for example,
various functionalized polyolefins, such as but not limited to
olefins modified by reaction with at least one at least one
unsaturated anhydride, unsaturated acid or unsaturated ester. As a
non-limiting example, useful functionalized polyolefins can include
an olefin modified by reaction with at least one unsaturated
anhydride, unsaturated acid or unsaturated ester selected from the
group consisting of maleic anhydride, citraconic anhydride,
itaconic anhydride, glutaconic anhydride, 2,3-dimethylmaleic
anhydride, maleic acid, fumaric acid, citraconic acid, itaconic
acid, mesaconic acid, glutaconic acid, acrylic acid, methacrylic
acid, crotonic acid, 2-pentenoic acid, 2-methyl-2-pentenoic acid,
dimethyl malcate, diethyl maleatc, di-n-propyl malcate, diisopropyl
maleate, dimethyl fumarate, diethyl fumarate, di-n-propyl fumarate,
di-isopropyl maleate, dimethyl itaconate, methyl acrylate, ethyl
acrylate, methyl methacrylate, ethyl methacrylate, methyl
crotonate, and ethyl crotonate. Polymer blends including one or
more maleic anhydride modified olefins, including without
limitation maleic anhydride modified polypropylene and maleic
anhydride polyethylene, can be particularly useful in various
applications. Some of these functionalities can also be created by
oxidizing an olefin, and other exemplary polymers include polymers
functionalized by oxidizing the polymer, for example, by oxidizing
a polyolefin.
[0115] Non-limiting examples of functionalized polymers useful
herein include maleated polyethylene commercially available from
Dow Chemical and maleated waxes such as the EPOLENE.RTM. waxes
commercially available from Eastman Chemical Company. Also useful
are polymeric or on-polymeric compounds having one or more
carboxyl, hydroxyl, and/or amine functional groups. In this
embodiment, the lower molecular weight component can include one or
more substantially crystalline or semicrystalline functionalized
compounds, which can also be lower molecular weight compounds that
have a melting point that is higher than the glass transition
temperature (Tg) of at least one polymer of the higher molecular
weight components of the blend. Although not wishing to be bound by
theory, it is currently believed that the increased functionality
imparted to the blends by incorporating such functionalized
polymers can increase wet-out and improve adhesion to cellulosics,
cotton, and other natural fibers, as well as synthetic fibers spun
from acrylic, nylon, and other polar polymers.
[0116] The functionalized additive can act as an "activating agent"
to promote adhesion of the yarn and can be selected based at least
in part upon the nature of an adhesive to be used with the yarn.
The functionalized additive can be incorporated into the polymer
(e.g., a polyolefin or polyester) using any suitable technique,
such as blending fiber formed of the functionalized additive with
the yarn, coating the yarn with the functionalized additive, and/or
incorporating the functionalized additive as a component in a
multicomponent fiber. The functionalized additive can be
incorporated into other synthetic polymers, such polyamides and
modified celluloses.
[0117] A non-limiting example of an activatable yarn includes a
polyolefin or a polyester yarn having a maleic anhydride modified
polyolefin incorporated therein. Activation of the maleic anhydride
modified polyolefin can promote bonding of the polyolefin and/or
polyester yarn using a nylon-based adhesive. Another non-limiting
example of an activatable yarn includes a polyolefin or polyester
yarn having an amine functionalized additive, such as stearamide,
incorporated therein as the functionalizing additive. Activation of
the stearamide can promote bonding of the yarn using an acid
functional binder.
[0118] At least one or more of the components of the polymer blends
of the invention can include a substantially crystalline or
semicrystalline polymer. Various embodiments of the invention can
include, for example, at least one or more substantially
crystalline low molecular weight polymer component(s). The term
"substantially crystalline or semicrystalline" is understood in the
polymer art and as used herein refers to a material's inherent
ability to crystallize when referring to material type, or
alternatively its current state of crystallinity when referring to
a particular product or object, as determined using conventional
techniques as known in the art. Methods for determining the degree
of crystallinity of a polymer are known in the art and include, for
example, DSC, density gradient tubes, and x-ray diffraction
techniques. Generally as used herein, the term crystalline or
semicrystalline refers to materials having a melt peak on DSC with
at least about 5 J/g of material, or more, for example, at least
about 10 J/g material or more. As non-limiting examples, polyesters
cay exhibit a melt peak on DSC of about 30 to about 50 J/g and
olefins can exhibit a melt peak on DSC of up to about 100 J/g.
[0119] The addition of a substantially crystalline polymer
component, including a low molecular weight substantially
crystalline polymer component, can promote the flow of the polymer
blend at low temperatures without blocking or fusing. The addition
of one or more substantially crystalline low molecular weight
polymers can, for example, result in a blend having a melting point
within about 20.degree. C. of the targeted blend application
temperature (i.e., the activating temperature, which can be, for
example, about 125.degree. C. or less).
[0120] In specific embodiments, the low molecular weight component
includes a substantially crystalline polymeric or non-polymeric
component (also referred to herein as a substantially crystalline
plasticizer). In such embodiments, the substantially crystalline
low molecular weight component can have a melting temperature (Tm)
that is higher than the glass transition temperature Tg of the
higher molecular weight polymer component of the blend. Again,
although not wishing to be bound by theory, it is believed that the
use of such materials in the blend can result in sharp flow
profiles. The polymer blend of this embodiment can be in any of the
various forms discussed herein, including fibers, nonwoven fabrics,
coatings, and the like. An exemplary blend in accordance with this
embodiment of the invention can include phenoxy compound having a
specific Tg (e.g., as the high molecular weight component) and a
substantially crystalline component (e.g., a plasticizer) having a
Tm that is higher than the Tg of the phenoxy component.
[0121] Each of the components can be present in the polymer blend
in an amount sufficient to impart the desired wetting and blocking
resistance properties thereto. In exemplary embodiments of the
invention, the blend can include at least about 10 percent by
weight of one, or both, of the higher molecular weight and the
lower molecular weight components. In further embodiments, the
polymer blends of the invention can include at least about 20
percent by weight, at least about 30 percent by weight, at least
about 40 percent by weight, and at least about 45 percent by
weight, based on the total weight of the polymer blend, of one or
both of the higher and lower molecular weight components.
[0122] The respective first and second components of the polymer
blends of the invention can include at least one, or a blend of
more than one, component thereof. For example, the first component
of the polymer blend can include at least about 10 weight percent
of one polymer or can include at least about 10 weight percent of a
blend of two or more polymers (in which case, the first blend
component can comprise less than 10 weight percent of a particular
polymer of the polymer blend). Similarly, the second component of
the polymer blend can include at least about 10 weight percent of
one compound or can include at least about 10 weight percent of a
blend of two or more such compounds (in which case, the second
blend component can include less than 10 weight percent of a
particular compound or component thereof). The compound of the
second blend component can include polymeric and non-polymeric
compounds.
[0123] In embodiments including a blend of polymers as the first
blend component, one or more of the polymers can meet one or more
of the criteria of molecular weight, Tg, etc., as discussed herein.
Similarly, in embodiments including a blend of compounds as the
second blend component, one or more of the compounds can meet one
or more of the criteria of molecular weight, Tm, etc., as discussed
herein.
[0124] The polymer components, and additives when present, can be
present in amounts outside of these ranges as well. Relatively high
amounts (e.g., at least about 10 percent by weight, or up to about
50 percent by weigh) of the low molecular weight component (which
can have a melt flow rate in the thousands) can be included in the
polymer blends without substantially decreasing the blocking
resistance of the polymer blend and also without significantly
decreasing the processability of the polymer blend. Similarly, the
polymer blends can include relatively high amounts (e.g., at least
about 10 percent by weight) of the high molecular weight polymer
component without significantly reducing the flow or wetting
properties of the blend as described herein.
[0125] The polymer components can be blended with one another using
conventional mixing techniques. In exemplary embodiments, the
polymer components can be dry blended with one another prior to
melting the polymers in subsequent extrusion or other polymer
processing steps. In other exemplary embodiments, separate polymer
melts can be combined with one another, for example, as polymer
melts pass through an extruder.
[0126] In other embodiments, the polymer blend can further include
at least one additive, as discussed herein, in a ratio of about
1:1:1 (read as the ratio of the high molecular weight polymer
component to the low molecular weight component to the additive).
As discussed herein, though, additives (when present) can be
present in amounts outside of this range.
[0127] Exemplary additives useful in the present invention can
include without limitation metallic particles, antimicrobials,
biocides, flame retardants, toxic absorbers, conductive agents,
abrasives, antioxidants, UV stabilizers, optically active
compounds, tracers, plating catalysts, particulates, reinforcing
agents, fillers, pigments, talc, glass fibers, clays, silicas,
mineral silicates, mica, odor absorbers, nano-particles, chemical
deactivators such as activated carbon, antistats, markers,
counterfeit tracers, fluorescents, fungicides, mildewcides,
phosphorescents, reflectants, "smart fabric" components,
polytetrafluoroethylene (PTFE), repellants, ointments, and the
like, and combinations thereof. The polymer blends allow for ready
application of a wide ranging amounts of additives and can be
particularly useful in the application of very low amounts of
additives. The blends can be useful for applying a very small
amount of additive substantially uniformly to a substrate with
durability. The resultant layer can in many instances be just a few
microns thick as well so that the particle size of the additive can
be very small. This can be useful in many applications in which the
additive particles might otherwise be buried below the skin of a
synthetic fiber.
[0128] The polymer blends have the additional benefit of having
inherently low color. This masks surface imperfections of a
substrate to which the polymer blend is applied, which in turn can
reduce dullness and create a "wetter," silkier look.
[0129] Additives can be incorporated into the polymer blends using
conventional techniques. The additive(s) can independently blended
with one or more of the polymer components and/or can be added to
the polymer blend. In exemplary embodiments, the additive(s) can be
dry blended with one or more of the polymer components of, and/or
with the polymer blend itself, prior to melting the polymer
components and/or the resultant polymer blend in subsequent
extrusion or other polymer processing steps. The additive(s) can
also be added to melts of the polymer components and/or of the
polymer blend, for example, as the polymer component and/or polymer
blend melt(s) pass through an extruder. A masterbatch of one or
more polymer components and/or the polymer blend and the
additive(s) can also be prepared and added to the polymer
components and/or polymer blend in dry or melt form. The
additive(s) can be used in the invention in various forms,
including powder, liquid and melt forms, as appropriate for a given
application.
[0130] The polymer blends can be suited for uniformly dispersing
and binding particulate additives to a substrate, durably anchoring
the additive to the substrate, for example via a thin flexible
coating, to optimize placement and maximize performance. As noted
herein, the polymer compositions of the invention can have sharp
flow profiles with improved flow at lower temperatures for bonding.
Yet, the polymer blends are not tacky or prone to block at normal
extremes of temperature exposure during transporting and
warehousing. The polymer blends can be used to deliver
discontinuous deposits (for example small islands) or a
substantially continuous yet breathable network that coats and
bridges the surface layer of the substrate (such as the surface of
fibers) in a construction. In addition, the polymer blend additive
systems can exhibit the permanence of a thermoplastic but can be
applied to a substrate at very low levels with good penetration and
dispersion.
[0131] While the foregoing describes a blend of polymers that
together function as an adhesive component, the present invention
also encompasses a variety of other types of adhesive components.
For example, in certain embodiments, the adhesive can comprise a
single polymeric material that itself is capable of functioning as
an adhesive.
[0132] In one embodiment, the adhesive component of the chenille
yarn comprises a maleic anhydride-grafted polymer, particularly
polyolefins, such as polypropylene. Polyolefins grafted with
anhydrides, including maleic anhydride, have been used previously
as film laminates. The present invention has realized the ability
of such materials for use as an adhesive component in a chenille
yarn. Any maleic anhydride-grafted polymer having physical
characteristics as described herein useful as an adhesive component
can be used in the invention. For example, U.S. Pat. No. 6,380,320
(which is incorporated herein by reference) describes
anhydride-grafted polymers and methods of preparing such polymers.
One specific example of such a polymer is AMPLIFY.TM. GR 209
(available from Dow Plastics), which is a maleic anhydride grafted
(MAH) polymer based on an ethylene-butene copolymer, exhibits high
flexibility and elasticity, can be utilized in monolayer and
coextruded films, and to enhance interlayer adhesion.
[0133] Other commercially available maleic-anhydride-functional
polyolefins are also useful as adhesives according to the present
invention. Such further adhesives include the entire EPOLENE.RTM.
series of polymers and polymer grades, including the "E" series,
available from Eastman Chemical Co., and the "C" series, available
from Westlake Chemical Co.
[0134] In other embodiments, the adhesive component of the chenille
yarn comprises a polyethylene oxide polymer. Polyethylene oxide
(PEO) is a semi-crystalline polymer that typically must be heated
above its melting temperature while in contact with a substrate to
allow entanglement of chains and subsequent crystallization upon
cooling. The overall adhesive strength of the interface can be
dependent on the thickness of the PEO layer. Any polyethylene oxide
compound having physical characteristics as described herein useful
as an adhesive component can be used in the invention, including
combinations of PEO with other compounds. For example, a wax
product containing polyethylene oxide, such as CARBOWAX.RTM.
PEG-1450 (available from Dow Chemical.) could be used as an
adhesive component. SENTRY.RTM. type polyethylene glycol polymers
are further, non-limiting examples of polymers that can be used
according to the invention.
[0135] Further to the above, the adhesive component of the
invention can comprise a variety of polar, low-melt thermoplastics.
A low-melt thermoplastic encompasses any material typically
recognized has being thermoplastic in nature that also has a
melting point below the melting point of the lowest melting
component of the core yarns. Preferably, the low-melt thermoplastic
has a melting point at least 5.degree. C., at least 10.degree. C.,
or at least 20.degree. C. below the melting point of the lowest
melting component of the core yarns. As used herein, a "low-melting
thermoplastic polymer" is a thermoplastic polymer having a melting
temperature of less than 180.degree. C. Thermoplastic polymers are
typically long chain polymer that can be either amorphous in
structure or semi-crystalline. These polymers are long chain,
medium to high molecular weight materials, whose general properties
are those of toughness, resistance to chemical attack, and
recyclability. Examples of materials useful as low-melt
thermoplastics in the invention include polyesters, such as
polyethylene terephthalate and polybutylene terephthalate, and
polyamides. Examples of other polar polymers useful as an adhesive
according to the invention include polytrylmethylene terephthalate
and polylactic acid, as well as, importantly, copolyesters and
copolyamides. Such polar thermoplastics can exhibit improved
adhesion to polar surfaces over non-polar melt-adhesives, such as
polyolefins. The polarity of these polymers also improves wetting
on other polar surfaces.
[0136] In a specific embodiment, the invention provides a chenille
yarn including a core yarn comprising a sheath/core multicomponent
fiber, wherein the sheath comprises an adhesive component as
described herein. In specific embodiments, the core component of
the multicomponent fiber comprises a polyolefin, preferentially
polypropylene. In such embodiments, the sheath can comprise any
material capable of functioning as an adhesive as described herein.
Particularly, the sheath component has a melting point below the
melting point of the core component. Preferably, the adhesive is
capable of imparting the physical characteristics, such as abrasion
resistance, described herein. In one embodiment, the sheath
comprises a maleated polyolefin.
[0137] In further embodiments, the chenille yarn can comprise two
or more core yarns, wherein one or more of the core yarns comprises
a sheath/core multicomponent fiber, as described above. In
preferred embodiments, both core yarns comprise such a
multicomponent yarn. Each core yarn may comprise a plurality of
fibers, wherein one or more of the fibers is a multicomponent
fiber. Accordingly, one or more of the fibers making up the core
yarn can be formed without an adhesive component applied thereto
(e.g., an uncoated polypropylene homopolymer fiber). Of course, the
chenille yarns can be formed of any combination of core yarns,
effect yarns, and adhesives described herein useful to prepare a
chenille yarn having the physical characteristics described
above.
[0138] In another aspect, the invention also provides a method of
preparing chenille yarns as described herein. In one embodiment of
the present invention, a chenille yarn is produced by a process
wherein at least one core yarn is fed into a chenille machine. The
at least one core yarn can comprise a multicomponent fiber having
an adhesive component as the sheath of a sheath/core or
islands-in-the-sea fiber or as an exposed surface of a segmented
fiber. Alternately, the adhesive component can be coated onto the
core yarn. Preferably, at least two core yarns are fed into the
chenille yarn, and at least one of the core yarns is as described
immediately above. If three or more core yarns are provided, at
least one core yarn can comprise the adhesive component and the
remaining core yarns can be free of the adhesive component or be as
immediately described above. Desirably, the adhesive component
included in the core yarn has a softening or melting point of at
least 10.degree. C. lower than the remaining components of the core
yarn.
[0139] A number of chenille machines are well known to those of
ordinary skill in the art and may be used to prepare the chenille
yarn of the present invention. Suitable chenille machines include,
but are not limited to, those disclosed in U.S. Pat. No. 3,869,850
issued to Gross; U.S. Pat. No. 3,969,881 issued to Boldrini; and
U.S. Pat. No. 5,259,178 issued to Sostegni.
[0140] The chenille yarn exiting the chenille machine includes the
effect yarn and can be subsequently treated to activate the
adhesive component and form a pre-bonded yarn wherein the pile or
effect yarn is securely attached to the core of the chenille yarn.
Alternately, the non-bonded chenille yarn can be fed directly to
suitable equipment for forming woven or knit fabrics. The formed
fabric can then be subjected to treatment to activate the adhesive
component and form a bonded fabric. In further embodiments, the
chenille yarn (either pre-bonded or non-bonded) can be wound onto
one or more cones for storage prior to fabric formation.
[0141] One method of producing the chenille yarns of the present
invention is schematically described in FIG. 11. Referring to FIG.
11, a first core yarn 105 and a second core yarn 107 are fed into a
chenille machine 115. At least one of the first and second core
yarns preferably comprise the adhesive component, such as
comprising a multicomponent fiber with the adhesive component
present at the surface of the fiber or as a coating one or both of
the core yarns (105, 107). As the chenille yarn 100 exits the
chenille machine 115, the chenille yarn 100 is taken up on a bobbin
120 and subsequently transferred onto a storage cone 125. In
alternate embodiments, the bobbin can be omitted and the chenille
yarn can be transferred directly onto storage cones. In such
embodiments, it is preferable to include one or more intermediate
rollers for properly tensioning the yarn. The chenille yarn can be
stored for later use in the preparation of chenille fabrics or
other products.
[0142] In another embodiment, illustrated schematically in FIG. 12,
the process comprises all of the same steps as described above.
However, in this embodiment, the process includes a step for
continuously bonding the chenille core. In particular, the method
incorporates an adhesive activation chamber 130 either upstream or
downstream of the bobbin (if present). Preferably, the chenille
yarn 100 is fed under tension through adhesive activation chamber
130 to activate the adhesive component of the core yarn(s) (105,
107). For example, the adhesive activation chamber 130 can comprise
a continuous autoclave or other type of heat unit capable of
activating the adhesive component, such as by heating above the
melting temperature of the adhesive component (e.g., by steam,
electric lamps, or gas burners). In certain embodiments the
adhesive activation chamber 130 can comprise an apparatus
generating radiation of a wavelength effective to activate the
adhesive. For example, an apparatus generating radiation in the
microwave range could be used. In such embodiments, the adhesive
component of the chenille yarn can include additives that effect
activation in response to the application of the radiation, such as
metal particles (which can cause the adhesive to increase in
temperature upon application of the microwave radiation. More
particularly, upon application of microwave radiation, the metal
particles can become heated and activate the surrounding adhesive
component (such as causing melting of the adhesive component).
Thus, the invention comprises activating the adhesive component by
applying microwave radiation.
[0143] The adhesive activation chamber 130 can optionally comprises
a separate cooling chamber 140. In this way, the present invention
allows for the preparation of a pre-bonded or pre-heat-set chenille
yarn that can be used in more vigorous yarn applications, such as
certain high energy methods, described below, for forming fabrics.
Known methods of forming adhesive chenille fabrics typically
require forming the fabric and then adhering the components.
[0144] The adhesive activation chamber 130 can have dimensions
(height and width) such that multiple chenille yarns may enter at
the upstream end 132 of the adhesive activation chamber 130. The
length of the adhesive activation chamber 130 may vary as long as
the chenille yarn is subjected to a sufficient amount of heat to
activate the adhesive component as chenille yarn passes from the
upstream end 132 to the downstream end 134 of the adhesive
activation chamber 130. As chenille yarn exits adhesive activation
chamber 130, the chenille yarn 100 is tacky due to the activated
adhesive. The optional cooling chamber 140 can allows chenille yarn
100 to harden prior to being wound onto the cone 125. Alternately,
the chenille yarn 100 can be passed through ambient conditions for
a distance sufficient to allow cooling prior to winding on the cone
125. The cooling chamber 140 has dimensions (height and width) such
that multiple chenille yarns 100 may enter the cooling chamber 140.
The length of the cooling chamber 140 may vary as long as the
chenille yarn 100 is sufficiently cooled to harden the activated
adhesive component. Desirably, the cooling chamber 140 comprises
air at atmospheric conditions.
[0145] Upon cooling, the chenille yarn 100 has the pile or effect
yarn securely attached to the core of the chenille yarn. Moreover,
the chenille yarn 100 has an "orientation memory" heatset into the
yarn even though the chenille yarn 100 is wound onto the cone 140.
The "orientation memory" minimizes the curling associated with yarn
when the yarn is unwound from a cone.
[0146] In yet another embodiment, the chenille yarn can be prepared
as described in relation to FIG. 11, and the chenille yarn can be
used in the preparation of a fabric. After formation of the fabric,
the completed fabric can be subjected to activating conditions so
that the adhesion component of the chenille yarn binds the effect
yarn securely to the core yarn. This method can be useful when
storage conditions and fabric preparation conditions are not likely
to adversely affect the chenille yarn. Certain conditions,
particularly fabric preparation conditions, can have greatly
adverse effects on the chenille fiber.
[0147] Thus, the present invention, in still another aspect,
provides various fabrics prepared using the chenille yarn described
herein. In certain embodiments, the chenille yarn can be fed
directly from the forming process (such as described in relation to
FIG. 11 or FIG. 12) into a fabric forming process (i.e., without
the need for winding onto the cone for storage). In other
embodiments, the previously formed chenille yarn can be obtained
and used in the fabric forming process.
[0148] In one embodiment, as shown in FIG. 13, a chenille yarn 100
(from a cone or other storage device, or directly from a
manufacturing process) is fed to a weaving machine 190 to produce a
woven fabric 200. Suitable weaving machines may include, but are
not limited to, shuttle looms, Rapier looms, air jet weaving
machines, and water jet weaving machines. The ability to use such a
variety of weaving machines, particularly air jet weaving and water
jet weaving, arises from the increased strength and stability of
the chenille yarn provided by the present invention. Specifically,
pre-bonded chenille yarns, as described above, have their effect
yarns sufficiently bonded to the core yarns so that the effect
yarns are not displaced during the air jet or water jet weaving
process. Preferably, weaving can proceed using the pre-bonded
chenille yarn so that greater than 90% of the effect yarns remain
bonded to the core yarn after weaving, even when using air jet or
water jet weaving methods. In specific embodiments, at least 92%,
at least 94%, at least 95%, at least 96%, at least 97%, at least
98%, or at least 99% of the effect yarns remain bonded to the core
yarn after weaving, even when using air jet or water jet weaving
methods.
[0149] In one embodiment of the present invention, the fabric 200
only requires washing and drying prior to consumer use. In other
embodiments of the present invention, the fabric 200 is subjected
to additional finishing processes. For example, the fabric 200 may
be subjected to a coater apparatus 220 for applying a coating or
finish thereto. Subsequently, the fabric 200 can be dried, such as
in a tenter frame 230, to produce a finished roll of chenille
fabric 250. Suitable fabric finishes include, but are not limited
to, latex coating, electreting, antistatic treatment,
stain-proofing treatments, flame retardant treatment,
anti-microbial surface treatments, dyeing and printing.
[0150] Fabrics made according to the present invention exhibit many
characteristics that illustrate the improvement over the art
achieved according to the invention. For example, the fabrics have
improved abrasion resistance, as described previously, that far
exceeds even the best chenille fabrics heretofore known in the
industry. This is achieved by use of the described chenille yarns
that incorporate the adhesive component of described herein.
Moreover, this is possible in light of the ability according to the
present invention to use multicomponent fibers in the core yarn of
the overall chenille yarn. It has heretofore not been possible to
prepare a stable multicomponent fiber that could function to
provide the core yarn of the chenille yarn as well as incorporate
an adhesive component into the overall chenille yarn. The present
invention achieves this feat, however, and the resulting products
benefit from the outstanding abrasion resistance imparted
thereby.
[0151] These benefits are seen in the improved performance of the
fabrics (i.e., the effect yarn fibers are harder to pull out of the
fabric, such as by abrasion) made with chenille yarns incorporating
the chenille core yarn of the invention, wherein the adhesive has
been activated after formation of the chenille yarn and either
before or after forming the fabric. This makes the fabrics more
durable for existing applications and renders the fabrics suitable
for applications for which their relatively poor abrasion
resistance currently renders them unacceptable. The improved
abrasion resistance can also provide further advantages, such as
permitting the use of cheaper, less-tightly-woven fabrics that
still provide abrasion resistance that is at least as good as, and
preferably greater than, the abrasion resistance of conventional
chenille fabrics.
[0152] Furthermore, as noted above, activating the adhesive after
forming the chenille yarn but prior to weaving the yarn into a
fabric, provides the chenille yarn with an improved durability that
makes the chenille yarn suitable for weaving on air-jet looms (or a
water jet apparatus). This is not possible with conventional
chenille yarns. Air-jet weaving can be a preferred method of
preparing fabrics because of its productivity (which translates
into decreased cost) in comparison to typical weaving methods
required with conventional chenille yarns.
[0153] Moreover, this increased durability can actually allow for
styling possibilities that currently unavailable using non-air-jet
looms. Likewise, this more durable chenille yarn can allow for
styling possibilities (regardless of the weaving technology) that
are currently not possible because they introduce excessive
exposure to abrasion that current chenille fabrics cannot
withstand. For example, weave patterns with lengthy "floats" or
jacquard patterns are typically not possible with chenille yarns.
Such varied styling methods are made possible using the chenille
yarn of the present invention.
[0154] The present invention will be further illustrated by the
following non-limiting examples.
EXAMPLE 1
Polymer Blend Adhesive
[0155] One adhesive was prepared by blending 45% of a high
molecular weight maleated polyethylene, such as EPOLENE.RTM. G-2608
(commercially available from Eastman Chemical) with 55% of a common
paraffin, such as IGI 1230. The resulting blend exhibits sufficient
melt strength for fiber spinning. Moreover, the adhesive bonds
(without pressure) to acrylic at 120.degree. C., which is a
60.degree. C. drop from the temperature required when using the
G-2608 polymer alone. The mixture does not exhibit blocking on the
package even when held at temperatures above the melting point of
the paraffin.
EXAMPLE 2
Polymer Blend Adhesive Coated on a Yarn
[0156] An adhesive was prepared by blending 50% of a maleated
polyethylene, such as EPOLENE.RTM. C-18 (number average molecular
weight of about 5,700 Da), with 50% of IGI 1230 paraffin wax. This
material was coated onto an acrylic core yarn of a chenille yarn.
The blend bonded in boiling water baths typical of dying processes,
yet did not exhibit blocking. This example exemplifies a
"100.degree. C. flow system" as discussed herein.
[0157] The paraffin component alone exhibited blocking and no
functionality for wet-out. The EPOLENE.RTM. wax exhibited too high
a melting point to flow at the desired temperatures. The blend can
penetrate readily into an effect yarn (such as an acrylic or cotton
effect yarn) at about 100.degree. C. (a temperature sufficient to
drive off water) and can bind it in place for improved wear
resistance.
EXAMPLE 3
Polymer Blend Adhesive Coated on a Yarn
[0158] A low molecular weight maleated polyethylene or
polypropylene wax was blended with a high molecular weight
polyethylene or modified polypropylene to gives results similar to
that exhibited by the blend of Example 2. The blend exhibited high
flow yet good fiber-forming properties at remarkably low
temperatures, and at the same time good integrity in uncontrolled
storage conditions. This example exemplifies a "150.degree. C. flow
system" as discussed herein.
[0159] In this example, the polyethylene alone exhibited poor flow
at this temperature and no functionality. The viscosity/melt
strength of the wax was too low to be spun into fibers. The blend
may be useful spun as the sheath of a bicomponent fiber. When
heated in an autoclave, the bonder readily penetrated into the
effect yarn and held it in place for improved wear resistance.
EXAMPLE 4
Polymer Blend
[0160] A phenoxy polymer (MW about 20,000) is an amorphous polymer
typically used as a binder in composite automotive structures such
as headliners. The Tg is about 90.degree. C. and is important to
preventing creep at elevated temperatures of an automotive
interior. The high molecular weight limits its ability to flow and
wet out. The lack of crystallinity makes it difficult to spin into
a fiber form, since it does not strain-harden.
[0161] Pentaerythritol tetrabenzoate (PETB, available as
LNIPLEX.RTM. 552 from Unitex Chemical Co.), is a non-polymeric
material having a molecular weight of 552 and a melting temperature
of 104.degree. C. at 10-25%. When PETB is blended with the phenoxy
polymer, the phenoxy blend flows much more readily, giving superior
wet-out. PETB is an example of a substantially crystalline
plasticizer, which in the invention as discussed herein has a Tm
that is greater than the Tg of the phenoxy. The improved
flowability also allows spinning into a fiber form, in part because
the melt now increases in modulus more when oriented (much like
solution spinning). Normally one would expect that such a
plasticizer would reduce Tg, which it does by as much as 25.degree.
C. However, because the PETB has a crystalline melt point higher
than the Tg of the phenoxy, the mixture in fact shows a cold-flow
point higher than the Tg of the unmodified phenoxy. Thus it
continues to be useful as a binder in elevated temperature
environments, does not creep excessively or become tacky as might
be predicted by the Tg.
[0162] The above is similar to the effect seen in Example 1.
Specifically, the high molecular weight maleated polyethylene in
Example 1 is a desirable binder, yet will not flow well at the
desired temperatures. Adding (crystalline) paraffin improves flow
without making the blend tacky.
EXAMPLE 5
Abrasion Resistance
[0163] Two fabrics were prepared using chenille yarn, and the
fabrics were tested to evaluate the abrasion resistance of the
fabrics according to ASTM D4157-02, as described above. Fabric 1
was a conventional fabric (as described below), and Fabric 2 was
made according to the invention.
[0164] Fabric 1 was prepared using a conventional chenille yarn
having a weight of 1350 yds/lb, having 14.5 turns/inch in the core,
and having a former length of 2 mm. The chenille core yarn was
formed of two yarns, each being a 14/1 spun yarn made of 60/40
PET/acrylic. The chenille effect yarns were 5/1 acrylic yarn.
Fabric 1 was formed to have a weight of 13.5 ounce per linear yard,
20 warp ends per inch, and 13.5 picks per inch. A 2 ounce per
linear yard acrylic latex backing was applied to the fabric. The
backing was considered necessary to allow the conventional fabric
to withstand the abrasion testing.
[0165] Fabric 2 (the inventive fabric) was prepared using an
inventive chenille yarn having a weight of 1250 yds/lb, having 14.5
turns/inch in the core, and having a former length of 2 mm. Two
chenille core yarns were used. The first core yarn was a 14/1 spun
yarn made of 60/40 PET/acrylic. The second core yarn was a
multicomponent fiber as described herein. Particularly, the yarn
was formed of 72 filaments and had an overall size of 320 denier.
Each filament was a sheath/core fiber having a polypropylene core
surrounded by a sheath formed of a polymer blend according to the
invention. The chenille effect yarns were 5/1 acrylic yarn. Fabric
2 was formed to have a weight of 13.5 ounce per linear yard, 20
warp ends per inch, and 13.5 picks per inch. A two ounce per linear
yard acrylic latex backing was applied to the fabric solely to be
in accord with the structure of Fabric 1. After formation, Fabric 2
was put through a 60 ft. oven set at 270.degree. C. at a rate of 25
yds/min to activate the adhesive component and bind the chenille
effect yarn.
[0166] Both fabrics were subjected to identical testing according
to ASTM D4157-02. The fabrics were also evaluated for tenacity,
seam slippage, and seam strength. The results of the tests are
provided below in Table 1. TABLE-US-00001 TABLE 1 Test Fabric 1
Fabric 2 Property (Conventional Fabric) (Inventive Fabric)
Tenacity: 50 lbs (warp direction) 120 lbs (warp direction) 50 lbs
(filling direction) 57 lbs (filling direction) Seam 30 lbs (warp
direction) 54 lbs (warp direction) Slippage: 30 lbs (filling
direction) 52 lbs (filling direction) Seam 50 lbs (warp direction)
89 lbs (warp direction) Strength: 50 lbs (filling direction) 52 lbs
(filling direction) Abrasion Failure after 6,000 to NO FAILURE
after Resistance: 12,000 cycles 100,000 cycles
As seen in Table 1, the inventive fabric out performed the
conventional in every test of the physical strength of the fabric.
Most importantly, the inventive chenille fabric did not fail the
test even after 100,000 cycles. The test is conventionally stopped
at 100,000 cycles as this is typically deemed to be the maximum
threshold for definitively characterizing a fabric in terms of its
abrasion resistance. In other words, the inventive fabric achieved
the highest performance typically evaluated in terms of abrasion
resistance. By contrast, the conventional fabric failed after only
6,000 to 12,000 cycles. Thus, the inventive fabric out performed
the conventional fabric by at least an order of magnitude.
[0167] Many modifications and other embodiments of the invention
will come to mind to one skilled in the art to which this invention
pertains having the benefit of the teachings presented in the
foregoing descriptions. Therefore, it is to be understood that the
invention is not to be limited to the specific embodiments
disclosed and that modifications and other embodiments are intended
to be included within the scope of the appended claims. Although
specific terms are employed herein, they are used in a generic and
descriptive sense only and not for purposes of limitation, the
scope of the invention being defined in the claims.
* * * * *