Note: Descriptions are shown in the official language in which they were submitted.
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TITLE OF INVENTION
DYED OLEFIN YARNS AND TEXTILE FABRICS USING SUCH YARNS
FIELD OF THE INVENTION
[0ool] The present invention relates to yarn and textile fabrics & film
manufactured using olefin pellets, fibers or yarns modified to accept dye at
low
temperatures.
RELATED PATENT
[0002] This invention is closely related to and represents an improvement
in certain respects over the invention of my U.S. Patent 8,759,430.
BACKGROUND OF THE INVENTION
[0003] One skilled in the art of fiber extrusion understands that an extruder
melts a polymer and a barrel screw forces the melted polymer through a
spinneret. The spinneret is similar to a shower head and contains many fine
holes. The melted polymer exiting these holes is in the form of molten
filaments.
These filaments have a diameter. The diameter of the filaments range in size
from diameters similar to cotton filaments and increase in size to the
diameter of
wool. The finer holes produce filaments suitable for apparel and as the holes
increase in size the filaments are suitable for carpets and home furnishings
such
as upholstery, draperies and rugs.
[0004] When the polymer used to create these filaments is nylon, the
resultant fibers or yarn will be manufactured into textile products that can
be dyed
using a nylon dye system. The nylon dye system is performed at a temperature
range of between 175 ¨ 200 F using water as the solvent along with other
chemicals known to one skilled in the art of nylon dyeing. It is very
desirable and
economical to dye at atmospheric pressures.
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[0005] If the polymers used to create filaments or fibers are polypropylene
(PP), they will not dye using the nylon dye system.
[mos] Olefin used in the textile field is usually polypropylene but any olefin
polymer can be modified using this invention. The dye system using the present
invention is the same as the system used to dye nylon. Anyone skilled in the
art
of dying nylon will be able to dye the modified yarns and fabrics made using
this
invention. The nylon dye system is unique because the dye is applied at normal
atmospheric pressures. The solvent is water and is effective at temperatures
from 175 F to 212 F.
[0007] Polypropylene usually is dyed by the pigment dye system which
colors the polymer during extrusion. Fabrics using the yarns of the present
invention are manufactured into greige (i.e., undyed) goods produced by the
knitting, weaving, tufted or non-woven process. Solid shades are achieved by
melt blending a dye enhancing additive (sometimes referred to herein as a
"master batch") into the yarn or fiber and subjecting the fabric to a dye
bath. The
dye enhancing additive used in the process is composed of polymers that are
readily available to one skilled in the art of fiber or yarn extrusion. One
does not
have to be skilled in the art of chemistry to use this invention.
mom When multiple ends of yarns embodying this invention are used,
each can contain differing percentages of dye-accepting additives. When the
yarns are manufactured into fabrics, the fabric will dye to multiple tones in
a
single dye bath. By increasing the amount of dyeable additive in the olefin
yarn
or fiber, the affinity for dye increases accordingly. The fabrics manufactured
according to this invention can be stored at the dye house undyed. Color is
added using conventional nylon dye machines or print dye methods. Surprising
and novel effects are achieved using economical conventional nylon dye systems
known to those skilled in the art. This invention is of particular usefulness
in the
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apparel, carpet and home furnishings industry. The olefin fabrics produced
feel
and appear as conventional fabrics but are approximately 30-38% lighter in
weight. This is due to the fact that the specific gravity of olefin is 0.91
BRIEF DESCRIPTION OF THE RELATED ART
[0009] Knitted and woven apparel fabrics and textile articles are an
enormous worldwide enterprise. Cotton is the predominant choice of fiber used
to make woven or knitted apparel textile fabrics. Many cotton-spinning systems
exist worldwide. Cotton yarns are easily produced for both apparel and home
furnishings using the cotton spinning system.
Egyptian and United States Cotton
[0010] The most common system of putting color on fabric is to dye the
woven, knitted, tufted or non-woven fabric. The fabric is placed in a machine
containing water, dyes and chemicals. The temperature of the liquor or dye
bath
is adjusted to the desired degree. The skilled operator will use this process
to
produce the desired shade on the fabric. The fabric is dried, and finished
according to the customer's specifications. The dye house is a capital-
intensive
operation that contains expensive dye and finishing equipment. A dye house in
addition to dyeing will have drying and finishing equipment such as
compactors,
chemical applicators and rolling or folding equipment.
[0011] The dyed cloth is cut and sewn into apparel garments or home
furnishing items such as draperies, bedspreads, rugs or upholstery. Carpet is
not
generally made using cotton, but relies mainly on synthetics. Nylon is the
most
preferred synthetic used to manufacture carpet. One skilled in the art of
dying
carpet will use the same skills to dye the product of this invention.
Synthetics:
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[0012] Many attempts have been tried to create an acceptable synthetic
fiber or yarn that is a good substitute for cotton and will process on
conventional
spinning equipment. The worldwide demand for cotton is such that synthetic
substitutes had to be introduced since there would not be enough acreage
available to produce enough cotton to meet the demand for affordable fabrics
and garments for the growing multitude of human population. It is very
desirable
to produce synthetic substitutes that can be used instead of or with cotton.
[0013] It is very desirable in the apparel and home furnishings industry to
have available a synthetic yarn or fabric that has novel characteristics.
Ideally
the synthetic fiber could be used to make a yarn for a fabric that would be
similar
to a fabric made from cotton or a blend of cotton and a synthetic. Most cotton
is
dyed at atmospheric pressures using cotton dyestuffs. Ideally, a blend of
synthetics and cotton would also dye at atmospheric pressures. This invention
facilitates dyeing polypropylene, olefin or blends of cotton and these
synthetics at
atmospheric pressures.
Olefin:
[0014] Olefin is a manufactured fiber, which is composed of at least 85%
ethylene, propylene or other olefin units. Olefin is an ideal substitute for
cotton
except for the fact that is not easily dyed on conventional dyeing or printing
systems. Olefin is easy and economical to produce into fiber that feels just
like
cotton. I have found that an olefin of 1.2 to 1.8 denier per filament cut to a
1.5" to
2" staple length is an ideal substitute for cotton yarn using the cotton
spinning
system to make yarn. In addition, Olefin is useful for the following reasons:
Olefin staple processes well on non-woven machines
Olefin fabrics feel similar to cotton
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Olefin will dry quickly
Olefin will pass moisture but retain body heat.
Olefin is very stain resistant
Disadvantage of Olefin Fiber and Yarn:
[0015] The main disadvantage of olefin is the fact that it is a fiber that is
not dyeable by conventional dye systems. Almost all olefin fiber and yarn is
pigment or solution dyed. Fabric made from pigment dyed yarn cannot be dyed
to fashion shades as orders are received. This makes fabric manufacture
prohibitively expensive and inventories too large to manage in the apparel and
home furnishings industry. Pigmented olefin is used primarily to manufacture
level loop Carpet.
SUMMARY OF THE INVENTION
[0016] An object of this invention is to use a polymer extruder to blend
active ingredients into a polypropylene or other olefin polymer and to
manufacture fiber, yarn or film that one skilled in the art will be able to
dye using
the nylon dye method. This can be achieved using an extruder to manufacturer a
master batch (sometimes referred to herein as "dyeable concentrate" or
"concentrate") in pellet form, for later mixing with the olefin component, or
by
combining the active ingredients, as well as the olefin component, in an
extruder
to manufacturer pellets ready to be extruded into fiber or yarn dyeable by the
nylon dye method. The active ingredients of this invention can also be dry
mixed
with polymer in an extruder to directly extrude fibers or yarns which will be
dyeable by the nylon dye method.
pm 7] In addition, an object of the present invention is to create a novel
knitted, tufted, woven or non-woven fabric using synthetic yarn that has many
of
the characteristics of cotton fabrics. Being dyeable at atmospheric pressures
is a
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further object of the present invention. To qualify, for wearing apparel the
fabric
has to be available in greige goods, be easy to dye on conventional systems,
be
soft to touch; the fabric must "breathe" and wick moisture away from the body.
Fabrics made using the synthetic yarns of the invention will be easy to wash
either by hand or machine and will not stain by ordinary household food
stains.
Fabrics made using this invention also have superior light and wash fastness.
[0018] Further objects and further scope of the present invention will
become apparent from the detailed description given hereinafter. It should be
understood however that the detailed descriptions and examples are given by
way of illustration only since various changes and innovations within the
spirit of
this invention will become apparent to those skilled in the art.
[0019] Although the cotton spinning system is the most widely used
system, one skilled in the art can produce fiber that can be made into yarn
using
any conventional spinning system. Air jet, open end, worsted, woolen and
modified worsted are some of the more common spinning methods. The fiber
length and denier can be varied to fit any spinning system. A modified worsted
spinning system is almost always used to spin carpet yarn.
[0020] In addition to staple fiber spun into yarn there is a large production
of continuous filament yarn. Continuous filament yarn is usually made up using
polypropylene when making apparel. The most common size is 70 denier to 50
denier. This invention can be applied to either fiber or continuous filament
yarn.
BCF or spun carpet yarn can also be made using this invention.
[0021] Briefly described, the present invention relates to a method of using
dyeable synthetic olefin yarns and fibers to manufacture knitted, tufted,
woven
and non-woven fabric greige goods that are easy to dye and process using
commercially available nylon dye or print systems.
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DETAILED DESCRIPTION OF THE MASTER BATCH OF THE INVENTION
[0022] The present invention relates to manufacturing a knitted, tufted,
woven or non-woven fabric or film using an olefin yarn or fiber that has been
enhanced to accept dye at atmospheric pressures. The olefin component of the
fiber or yarn does not dye but a master batch additive that is melt blended
into
the olefin of the present invention will accept dye that is used at dye
facilities to
dye nylon or blends of nylon and cotton. This invention uses small percentages
of
a master batch of a compounded additive blended in a standard fiber extruder
with untreated olefin to create yarns that are made into woven, knitted,
tufted or
non-woven greige goods fabric. The fabrics of this invention are stored as
uncolored inventory. Very high temperatures, normally used to dye synthetics
are not necessary to dye the fabrics of the invention. A temperature of 175 F
¨
200 F is ideal for the dyeing process. Pressurized dye machines are not
necessary to achieve proper dye coloration. The present invention results in
an
energy saving of 50% compared to conventional procedures. Bright shades of
any color can be achieved when dyeing fabrics according to the present
invention.
Multitones:
[0023] In addition to just one solid color, tonal effects are easily achieved
using the piece dye system. Olefin yarns blended with a dyeable concentrate of
from 1% to 20% by weight of the goods are used to make fabrics dye to multi-
tones of the same shade in one dye bath. This is achieved by melt blending
varying strengths of a dyeable concentrate specified in this invention into
the
olefin fibers or yarns. By example, I will call a yarn with 10% dyeable
concentrate
A, a yarn with 4% dyeable concentrate B and a yarn with 1.5% dyeable
concentrate C. When yarns A, B, and C are placed together on fabric forming
machines, such as a tufting or weaving machine, the resultant fabric is dyed
into
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novel three self tones of a color in a single dye bath. One will be dark, one
medium and one light. A preferred range of concentrate in the compounded mix
for this purpose is from 1% to 15%, by weight.
[0024] When a fabric is made using yarns containing two different dye
levels (i.e., levels of the master batch concentrate) and one yarn without any
concentrate the result will be a fabric with yarns having two tones of color
and a
white (undyed) yarn. This aspect creates novel and surprising effects. One
skilled in the art will find many pleasing ways to make novel fabrics using
this
invention.
Solid Shades:
[0025] Fabric made from modified dyeable olefin yarn will dye a solid
shade when made using yarn that contains only one level of dyeable
concentrate. (It will be understood that the terms "dyeable olefin" or
"dyeable
polypropylene", as used herein, refer to olefin or polypropylene dyeable at
atmospheric pressures using a nylon dye procedure, unless the context clearly
indicates otherwise.) A preferred amount of dyeable concentrate blended with
untreated olefin for this purpose is 8% on the weight of the goods. Other
concentrations can be used to vary the dye take up but I have found the
preferred mixture to be 8% of the concentrate on the total weight of the goods
to
make excellent solid shades.
[0026] The Tietz US patent 5,130,069 shows procedure for dying of
polypropylene fibers where the polypropylene fibers have been modified with a
composition of nylon 6,6 and several other components in conjunction with
bulking of the fibers. Preparation of the dye receptive additives requires the
use
of a high pressure (250psi) autoclave and temperatures of 200 - 290 C.
Moreover, the nylon 6,6, which is a crystalline form of nylon, is altogether
unsuitable for apparel fibers, which have to be extruded through fine nozzles,
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which quickly become clogged by crystalline nylon. Uniform dying of the fibers
is
also difficult to achieve because of non-uniformities in the resulting
composition
when utilizing the crystalline nylon 6,6.
[0027] The present invention makes the use of the following "off the shelf
ingredients used to manufacture dyeable polypropylene. Anyone skilled in the
art
of fiber or pellet extrusion will be able to practice this invention.
ACTIVE INGREDIENTS AND COMPONENTS OF THE MASTER BATCH OF
THIS INVENTION
[0028] Amorphous Nylon - This material is selected because it accepts
dye using the nylon dye system. It is not crystalline and will evenly disperse
during the melt extrusion process. This material is available as pellets. It
will not
clog the fine holes in a spinneret. Preferred Supplier: EMS¨GRIVORY America.
Product description: G-16 or XE-3830
[0029] Maleic Anhydride (MAH)-Modified Polypropylene - This material
is used to allow different polymers (nylon and or olefin), to be compatible.
Maleic
Anhydride is reacted with polypropylene and is available from suppliers in
pellet
form. A preferred material is the maleic anhydride modified homo polypropylene
manufactured by Polyram (Israel). The product, which is available in the
United
States from Harry Gaffney Company, Inc. as BondyramTM 1001, corresponds to
MAH #3200, also available from Harry Gaffney Company. A useful alternative to
the maleic anhydride modified polypropylene, especially for fine denier
fibers, is
maleic anhydride modified linear low density polyethylene manufactured by
Polyram and available in the United States from the Harry Gaffney Company,
Inc.
as BondyramTM 4108.
[0030] NYLON 6 OR 6,6 - available in pellet form from various suppliers.
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[0031] When practicing this invention, a person skilled in the art can create
a master batch which can be added to a polypropylene fiber extruder to create
and extrude a fiber, yarn or film that is dyeable at atmospheric pressure
using the
nylon dyeing system. One can also create a blended pellet containing the
master
batch pre-mixed with polypropylene that can be extruded into a finished
polypropylene fiber, yarn or film dyeable by the nylon dye method. If desired
and
with the proper extruder equipment, the components of the master batch can be
dosed directly into an extruder together with the polypropylene to achieve an
extruded product of the desired mix. Preferably, the polypropylene component
of
the blend has a melt flow index (MFI) of 18-35. Extrusion temperatures for the
mixing, blending and extruding of the master batch or of the dyeable olefin
mix
desirably are in a range of 250 C to 260 C for best results.
[0032] The master batch of the invention preferably contains 10% to 50%
amorphous nylon and preferably 20% or more of the amorphous nylon.
Otherwise, the nylon 6 or nylon 6,6 may be too crystalline to extrude
properly.
Theoretically, up to 90% of the master batch may be made up of amorphous
nylon. However, amorphous nylon is quite expensive, and an important purpose
of this invention is to incorporate significant percentages of nylon 6 and/or
nylon
6,6 into the mix to reduce the cost while maintaining performance. In the
master
batch of the invention, the nylon 6 or nylon 6,6 can be present in amounts
ranging from 80% to 40%. Regardless of the relative proportions of amorphous
nylon and nylon 6 or nylon 6,6, it is preferred that the master batch contain
about
10% of MAH-modified polypropylene. For best results, master batch pellets
should be dried for about four hours at a temperature of about 190 F.
[0033] In a process according to the invention, the master batch
as
described above can be combined with polypropylene in a range of 1% to 20% of
the master batch to 99% to 80% of polypropylene with a melt flow index (MFI)
of
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18-35. An advantageous form of finished fiber or yarn typically will contain
from
0.75%% to 5% amorphous nylon, from 1.95% to 13% nylon 6 and/or 6,6, 0.3% to
2%% MAH-modified polypropylene, and 97% to 80%% polypropylene with a melt
flow index (MFI) of 18-35. Nylon 6 or 6,6 can be used interchangeably, either
individually or in mixtures.
DYEABLE OLEFIN
[0034] A preferred method of rendering polyolefin dyeable by the nylon
dye method pursuant to the invention is as follows:
[0035] A master batch mixture as described above, of amorphous nylon,
polypropylene modified with maleic anhydride, and nylon 6 or 6,6 are
compounded with polyolefin. Amorphous nylon is uniquely beneficial because it
is non-crystalline and will easily disperse into polypropylene at a
temperature that
will not destroy the properties of olefin. Moreover, nylon 6 or 6,6 will blend
with
amorphous nylon and, when so combined, will not create fibrils during
extrusion.
Polypropylene modified with maleic anhydride enables the nylon to be
compatible
with the polypropylene. By using the component ingredients of this invention,
one skilled in the art of extrusion can make polyolefin fiber or continuous
filament
yarn using conventional fiber extrusion machines. No special equipment is
needed to perform this operation. The olefin fiber or yarn produced using this
system will be dyeable using the nylon dye method. The master batch invention
uses an amorphous nylon product called G-16 or XE-3830 from EMS-GRIVORY
America, polypropylene (18-35 MFI) modified with about 1% maleic anhydride
No. 3200, from Harry Gaffney, and nylon 6 or 6,6 available from various
suppliers.
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Master Batch Additive Examples:
[0036] 1) A "standard" mix of 25% amorphous nylon, 65% of nylon 6 or
6,6 and 10% MAH-modified polypropylene, is extruded into pellets as a master
batch or concentrate. When 10% of this master batch is blended with 90% olefin
polymer, the extruded fiber or yarn will contain 2.5% amorphous nylon, 1% MAH-
modified polypropylene, 6.5% nylon 6 or 6,6, and 90% polypropylene with a melt
flow index of 18-35. The result is a fiber or yarn that will easily dye at
atmospheric pressures using the nylon dye method.
[0037] The above example is merely a suggestion, but by experimentation
one skilled in the art of extrusion could vary the master batch composition
and
the dosing percentages to suit their needs. One skilled in the art would also
be
able to dry mix the formulation of this invention and dose it into an
extruder.
[0038] The polymers, using this invention will have the following
characteristics:
1. Will pass through very fine holes in the spinneret
2. Ingredients are evenly distributed throughout the fibers
3. Will accept dyes using the nylon dye system
4. The resultant fibers or filaments look and feel "normal"
5. Economical for commercial use.
[0039] The following examples illustrate usages of the invention in
connection with various apparel, furnishings and carpet applications:
Example 1 -- Solid Color Apparel Made from Spun Yarn of this invention:
[0040] Staple fiber is produced in a standard fiber extruder comprising a
blend of 90% olefin and 10% of the dyeable concentrate (master batch) of this
invention. The fibers are 1.5 denier and cut to a length of 1.5".
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[0041] The fiber is converted to a 30/2 cc yarn using a conventional ring
spinning system. One skilled in the art could also use an air jet system, open
end
system, ring spinning or a worsted system. 500 lbs of dyeable yarn is
produced.
[0042] The 30/2 yarn is knitted on an 18 gauge Jersey Cut knitting
machine. A 500 pound roll of knitted fabric is produced which weighs 6.5
ounces
per square yard.
[0043] The knitted roll is dyed in a standard nylon dye machine. 1% low
energy disperse blue is applied owg following the standard nylon dye procedure
at 200 F. The dyed roll is removed, slit open, dried and finished on a
standard
frame through a standard oven. The oven temperature is set not to exceed
280 F which is below the melting point of olefin. The solid dyed knitted
fabric is
rolled into a number of standard rolls.
Example 2 -- Solid Color Apparel Made from Continuous Filament Yarn
Made According to this Invention:
[0044] Continuous filament yarn is produced in a standard fiber extruder
comprising a blend of 90% olefin and 10% dyeable additive of this invention.
The
yarn is comprised of 50 filaments of 2.0 denier to make a 100/50/1 continuous
filament yarn.
[0045] The 100/50/1 continuous filament yarn is knitted on an 18 gauge
Jersey Cut knitting machine. A 500 pound knitted roll is produced which weighs
6.0 ounces per square yard.
[0046] The knitted roll is dyed in a standard nylon dye machine. A medium
energy disperse dye blue is applied following the standard nylon dye procedure
at 200 F. The dyed roll is removed, slit open, dried and finished on a
standard
frame through a standard oven. The oven temperature is set not to exceed
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280 F which is below the melting point of olefin. The solid dyed knitted
fabric is
rolled onto a number of standard rolls.
Example 3 -- Continuous Filament BCF Dyeable Olefin Carpet Yarn:
[0047] Continuous filament yarn is manufactured using a standard BCF
carpet yarn extruder comprising a blend of 90% olefin and 10% dyeable additive
of this invention. The yarn is comprised of 75 filaments of 20 denier per
filament
to make a 1500/75/1 continuous filament yarn.
[0048] The yarn is tufted on a 1/8th gauge level loop carpet tufting
machine. The carpet is dyed on a continuous dye range using a standard nylon
dye system. The carpet is dried, backed and rolled ready to ship to a
customer.
[0049] An alternative procedure is to twist and heat set two ends of the
above yarn to create a 1500/75/2. This yarn is tightly tufted on a 1/8 gauge
cut
pile machine to create an undyed greige carpet. The carpet is dyed on a
continuous dye range using the nylon dye method, backed rolled and ready to
ship.
Example 4 -- Tri-Tone Continuous Filament BCF Olefin Carpet Yarn:
[0050] Continuous filament yarn is produced on a standard three color
olefin BCF carpet yarn extruder. 1/3rd of the olefin yarn comprises a blend of
85% olefin and 15% dyeable concentrate of this invention, 1/3rd of the yarn
comprises 90% olefin and 10% dyeable additive of this invention, and 1/3rd of
the
yarn comprises a black pigmented filament. The finished yarn is comprised of
90
filaments of 20 denier per filament to make a 1800/90/1 continuous filament
yarn.
30 Filaments will dye deep, 30 filaments will dye lighter, and 30 pigmented
filaments will not accept any dye. The shape of the cross section of each
filament
will be trilobal.
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[0051] The continuous filament BCF yarn is tufted on a 1/8th gauge level
loop carpet tufting machine. The carpet is dyed on a continuous dye range
using
a standard nylon dye system. A mixture of red & blue dye is used to create a
brown color. The pigmented portion will not accept any dye and remains black,
the portion containing 15% of the additive will dye deep brown and the
remaining
portion with 10% additive will dye light brown. The result is a tri tone
carpet
colored black, deep brown and light brown. The carpet is dried, backed and
rolled
ready to ship to a customer. This serves as an example only. One skilled in
the
art can vary the amounts of additive and pigments to create a wide variety of
desirable and pleasing effects.
Example 5 -- Printing Dyeable Olefin Fabrics:
[0052] Screen Printing- A knitted fabric comprising a 150/1 Denier dyeable
olefin made according to the invention was fed to a 6 color aqueous continuous
screen-printing machine. A standard dye paste of dyes was prepared for each
screen with thickener. The screens were made to allow a six color pleasing
floral
pattern to be produced. The print paste was screened on the fabric one color
at
a time. The fabric was fed to a steam box to set the dyes. Two to four minutes
of steam at 212 F is required to set the dye. The fabric was passed through in
a
continuous system, washed of excessive dyes and dried being cautions not to
exceed 295 F. The result was a pleasing 6-color floral printed knitted olefin
fabric. In another embodiment a similar printing system is used on a carpet
printing machine to print tufted carpets using dyes available to the printed
carpet
trade.
[0053] The novel floral pattern effect was achieved without bleeding or
excessive pick up. Drying time was greatly reduced and the oven was set to
allow 295 F to come in contact with the fabric. It is understood that tufted
and
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woven fabrics can also be processed using the atmospheric nylon printing
technique.
Example 6-- Space Dve Printing Color on Olefin Yarn using the Knit de Knit
Process:
[0054] a.) Pellets of olefin with a Melt Flow Index of 18-35 are
extruded
and intimately blended using the above dyeable concentrate of the invention. A
blend of 90% olefin and 10% of the master batch dyeable concentrate is
extruded
into a staple mass using conventional staple extrusion equipment. The fiber
dpf
is 1.5 and is cut to 1.5". Approximately 1,000 pounds of staple are produced
and
baled. The denier per filament is close to that of cotton and so is the staple
length.
[0055] b.) The olefin bales of staple fiber are blended together at the
cotton carding process and made into roving. The roving is made using
conventional cotton equipment is spun into a 10/1 cotton count and taken up on
3
pound packages. Approximately 1000 pounds of yarn is produced. The 10/1
yarn is plied to make a 10/2 dyeable yarn.
[0056] c.) Knitted Sleeve - The 10/2 olefin yarn is knitted into a
single
endless sleeve.
[0057] d.) Space dye printing - Three colors are printed on the sleeve
as part of a knit de knit process well known in the art. This is a continuous
process whereby the undyed sleeve passes through a squeegee roller
submerged in a dye tank to apply the first shade of color. The sleeve
continues
to a second patterned roller, which overprints a second shade and then
continues
to a third roller, which overprints a patterned third shade. The base shade is
usually light and the 2nd shade medium while the third shade is deep. The
colored knitted sleeve is exposed to steam for at least 2 minutes and
preferably 4
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minutes. This sets the dye to an acceptable depth of shade. The knitted sleeve
has a solid background shade of beige overprinted with deep brown and
charcoal. The sleeve is then washed and dried on the continuous range. The
dryer is set at a low temperature of 250 F and the water is flashed off. The
dried
sleeve is collected in a can container and moved to the winding room.
[0058] e.) The resultant sleeve is de-knitted or wound onto a
yarn
package using a winding operation well know to those skilled in the art. The
yarn
is a pleasing beige color with dots of dark brown and dark charcoal and is put
up
on 3-pound cones.
[0059] f.) The 10/2 olefin space dyed yarn is knitted on a 10
cut
knitting machine. A pleasing three-tone space dyed fabric is the result. The
space dyed fabric of olefin is surprisingly free of patterns usually
associated with
skein or dip dyeing of sweater yarns. The fabric is washed with hot water in a
jet
dye or winch dye machine to add bulk and to clarify the colors. This also
assures
the fact that the finished sweater will not shrink when washed by the end
user.
The fabric is dried in a cool oven at 200 F. While it is not necessary to wash
the
fabric, it is worth the extra step to make the fabric shrink proof.
[NW g.) The space dyed sweater fabric is cut and sewn
and is
surprisingly novel. If olefin is used, the fabric will be 30% lighter in
weight than a
cotton sweater made to the same specifications. While this example uses a 10/2
yarn, it should be noted that any size dyeable olefin of the invention that
would be
practical to go through the knit de knit system would be suitable. This system
is
especially popular to make space dye carpet yarn. Many pleasing color effects
can be achieved and should not be limited to the example set forth. Space dye
Carpet yarn is used in very large quantities. One skilled in the art should
experiment to find a pleasing result with either spun yarn or continuous
filament
yarn.
CA 02893416 2015-06-02
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[0061] Other methods of space dyeing or print dyeing yarn can be used.
One skilled in the art will adjust the various machines to the specifications
outlined above. Warp printing or package impregnation are two other common
methods used to space dye yarns.
[0062] It should be understood that the herein described forms of the
invention are intended to be illustrative of the basic principles of the
invention and
are not intended to be in any way limiting. Accordingly, reference should be
made to the following appended claims in determining the full scope of the
invention.
