Field of The Invention
5 [001] The present invention relates to fabrics and methods for manufacture of fabrics.
In particular, the present invention relates to a fabric having optimized characteristics
including improved softness, absorbency and durability – for example, for use as a pile
fabric or as a bedsheet.
10 Background
[002] Fabrics may be manufactured for several different end uses, including as clothing,
for towels, for bed linen (e.g., bedsheets), as terry fabrics, for cleaning products, carpets
and the like. Particularly for end uses where the fabric is intended to contact a user’s skin
15 (for example, in the case of towels or bedsheets) it is considered advantageous if the
fabrics are durable, soft and absorbent. For example, in cases where the fabrics are used
to manufacture towels or bed linen (such as bedsheets), there is a need for a pleasant feel
and for improved absorbency, while at the same time retaining durability characteristics.
20 [003] It is known to manufacture fabrics such as towels and bedsheets using yarn spun
from 100% cotton fibers. In manufacturing such fabrics, the yarn is woven on a loom with
the 100% cotton yarn being used for each of the ground yarn, weft yarn and pile yarn. In
such fabrics, the 100% cotton content of the fabric makes it particularly desirable from
hand-feel and absorbency perspectives. Such fabrics are however less durable – and have
25 a short life of acceptable use.
[004] With a view to improve durability, fabrics may therefore be manufactured using a
mix of polyester and cotton fibres. For example, all yarns (e.g. the ground, warp and pile
yarns) of a fabric may be manufactured using a polyester cotton mix. In another example,
30 the pile yarn may comprise a 100% cotton yarn, while polyester yarn (or a polyestercotton mix) may be used for the ground and weft yarns. In either case, it has been found
that while there is a significant increase in durability, there is a corresponding
deterioration in overall hand-feel for the user, as well as in absorbency of the resulting
3
fabric. It has also been found in conventional fabrics, that with multiple washes, there is
a corresponding deterioration in softness, absorbency and durability characteristics.
[005] There is accordingly a need for a fabric (and for methods of manufacturing fabrics)
5 that improve durability of the fabrics without deterioration in overall hand-feel and in
absorbency of the fabric. There is additionally a need for fabrics (and for methods of
manufacturing such fabrics) which retain softness, absorbency and durability
characteristics even after multiples washes.
10 Summary of the Invention
[006] The present invention relates to a fabric having optimized characteristics
including improved softness, absorbency and durability – for example, for use as a file
fabric or as a bedsheet.
15
[007] In an embodiment, the invention comprises a cotton-polyester blend fabric
comprising (i) a plurality of interwoven yarns, wherein at least one of the interwoven
yarns is a blended yarn comprising a plurality of cotton fibers and a plurality of polyester
fibers twisted together, wherein the blended yarn conforms to:
20
5315
C(blended)
×
Wt (polyester)
N(p)
= 𝑓
and wherein:
25 C(blended) is a count of the blended yarn;
Wt (polyester) is a percentage by weight of polyester fibers within the blended
yarn
30 N(p) is the number of polyester fibers distributed across the blended yarn’s
cross-section
4
and 0.6 ≤ 𝑓 ≤ 1.0.
[008] The invention additionally provides a cotton-polyester blended yarn for weaving
an absorbent fabric, comprising a plurality of cotton fibers and a plurality of polyester
5 fibers twisted together - wherein the blended yarn conforms to:
5315
C(blended)
×
Wt (polyester)
N(p)
= 𝑓
and wherein:
10
C(blended) is a count of the blended yarn;
Wt (polyester) is a percentage by weight of polyester fibers within the blended
yarn
15
N(p) is the number of polyester fibers distributed across the blended yarn’s
cross-section
and 0.6 ≤ 𝑓 ≤ 1.0.
20
[009] The invention also provides a method for manufacturing a cotton-polyester blend
fabric, comprising the steps of: (i) providing a blended yarn comprising a plurality of
cotton fibers and a plurality of polyester fibers twisted together, wherein the blended
yarn conforms to:
25
5315
C(blended)
×
Wt (polyester)
N(p)
= 𝑓
wherein:
30 C(blended) is a count of the blended yarn;
5
Wt (polyester) is a percentage by weight of polyester fibers within the
blended yarn
N(p) is the number of polyester fibers distributed across the blended
5 yarn’s cross-section
and 0.6 ≤ 𝑓 ≤ 1.0;
and (ii) weaving a fabric comprising a plurality of interwoven yarns, wherein the
10 blended yarn comprises at least one of the interwoven yarns.
[0010] The invention additionally provides a method for manufacturing a cottonpolyester blended yarn for weaving an absorbent fabric, comprising the steps of (i)
preparing a blended yarn comprising a plurality of cotton fibers and a plurality of
15 polyester fibers twisted together, wherein the blended yarn conforms to:
5315
C(blended)
×
Wt (polyester)
N(p)
= 𝑓
wherein:
20
C(blended) is a count of the blended yarn
Wt (polyester) is a percentage by weight of polyester fibers within the
blended yarn
25
N(p) is the number of polyester fibers distributed across the blended
yarn’s cross-section
and 0.6 ≤ 𝑓 ≤ 1.0.
30
6
Brief Description of the Drawings
[0011] Figure 1 illustrates a fabric cross-section of a flat fabric comprising
interwoven ground and weft yarns.
5
[0012] Figure 2 illustrates a fabric cross-section of a pile fabric comprising
interwoven ground, weft and pile yarns.
[0013] Figure 3 illustrates a process flow corresponding to a method of
10 manufacture of a yarn in accordance with the teachings of the present invention.
Detailed Description
[0014] The present invention relates to a fabric having optimized characteristics
15 including improved softness, absorbency, and durability – for example, for use as a pile
fabric or as a bedsheet.
[0015] Figure 1 illustrates a fabric cross-section 100 of a flat fabric comprising
interwoven ground yarns 102 and weft yarns 104. The flat fabric of a kind illustrated in
20 Figure 1 may be used for manufacturing of bedsheets or other bed linens in accordance
with the teachings of the present invention.
[0016] Figure 2 illustrates a fabric cross-section 200 of a pile fabric comprising
interwoven ground yarns 202, weft yarns 204 and pile yarns 206. The pile fabric of a kind
25 illustrated in Figure 2 may be used for manufacturing of towels or other terry fabrics in
accordance with the teachings of the present invention.
[0017] The invention as described in the present application is based on the
surprising discovery that the characteristics of a cotton-polyester blended fabric
30 (comprising a blend of cotton and polyester) can be optimized to simultaneously ensure
durability of the resulting fabric, along with a pleasant hand feel as well as high
absorbability. In other words, it has been discovered that a fabric comprising a cottonpolyester blend can be manufactured in accordance with the teachings of the present
7
invention without compromising on feel of the fabric and / or moisture absorbency that
would ordinarily be observed in a 100% cotton fabric, while at the same time achieving
significantly enhanced durability.
5 [0018] The invention also ensures that such fabrics retain softness, absorbency
and durability characteristics even after multiples washes. As a result, the fabrics of the
present invention have been found to retain their characteristics of hand-feel and
absorbency better than cotton fabrics even after multiple washes. So for example, it has
been surprisingly discovered that even after being subjected to 75 to 100 wash cycles,
10 fabrics according to the present invention exhibit better hand-feel and absorbency than
a 100% cotton fabric produced by conventional methods.
[0019] For the purposes of this written description, the following terms shall be
understood according to the definitions provided below.
15
[0020] “Absorbency” refers to the propensity of a material to take In an retain
liquid, such as water.
[0021] “Base material” refers to material used for manufacturing a yarn or fabric
20 – and for the purposes of the present invention may include any of cotton or cotton
blends.
[0022] “Blend” refers to a textile or yarn containing two or more different fibers,
or variants of the same fiber, or different colors and grades or the same fiber.
25
[0023] “Blending” refers to the mixing of quantities of different fibers, or of the
same fiber taken from different lots – to produce a uniform product.
[0024] “Carding” refers to a process in manufacturing spun yarn in which the
30 fibers are separated, distributed, equalized and formed into a web. The web can be thin
or thick. The process of carding removes impurities, as well as short or broken fibers.
[0025] “Count” or “Yarn Count” is a numerical expression which defines fineness
or coarseness of a yarn. Stated differently, count is a number which indicates the mass
8
per unit length or the length per unit mass of yarn. Count of a yarn can be expressed as a
direct count (the number of weight units in one length unit), or as an indirect count (the
number of length units in one weight unit).
5 [0026] “Denier” or “Denier system” refers to units of yarn count, represented as a
direct count, wherein the number or count of a yarn in the denier system is the weight in
grams of a 9000 meter length of said yarn.
[0027] “Hank” refers to a definite length of textile material that varies according
10 to the material. A hank of wool is 560 yards, a hank of cotton or silk is 840 yards, and a
hank of linen is 300 yards. For the purposes of the specification, the term “Hank” is
defined as the Nec Count for the material in process, sliver and roving.
[0028] “Nec Indirect count”, “Nec” or “Ne” refers to units of yarn count,
15 represented as an indirect count, wherein the number or count of a yarn in the Nec
system is the number of hanks of 840 yards per pound weight of yarn.
[0029] “Pile” refers to a surface effect on a fabric formed by tufts or loops of yarn
that stand up or away from the body of the fabric – and is observed in fabrics such as terry
20 fabric or towelling fabric.
[0030] “Sliver” refers to a continuous strand of loosely assembled fibers without
twist. The production of the sliver is the first step in the textile manufacturing operation
that brings the staple fiber into a form that can be drawn and eventually twisted into a
25 spun yarn.
[0031] “Warp” or “Ground” refers in woven fabric to the yarns that run lengthwise
and are interwoven with the weft (or fill) yarns.
30 [0032] “Weft” or “Fill” refers in woven fabric to the yarns that run substantially
perpendicular to the warp yarns.
[0033] The present invention provides a fabric construction, wherein one or more
the ground yarns, warp yarns and / or pile yarns of the fabric comprises a blended yarn
9
comprising both cotton fibers and polyester fibers, and that conforms to the following
parameters:
5315
C (blended)
×
Wt (polyester)
N(p)
= 𝑓
5
• wherein the variable ‘C (blended)’ represents the count of the blended yarn
comprising both cotton fibers and polyester fibers
10 • wherein the variable ‘Wt (polyester)’ represents the percentage by weight of
polyester fibers within the blended yarn i.e.:
100 ×
Weight of polyester fibers per unit length within the blended yarn)
Total weight of the blended yarn per unit length
15
• wherein the variable ‘N(p)’ represents the number of polyester fibers included
within (or distributed across) the cross-section of the blended yarn
• and wherein 0.6 ≤ 𝑓 ≤ 1.0
20
[0034] The yarn comprises a plurality of cotton fibers and a plurality of polyester
fibers blended and twisted together (for example, s-twisted or z-twisted together) to
form a blended yarn conforming to the above described parameters.
25 [0035] The use of a cotton-polyester blend has been found to result in an improved
durability, while conforming to the parameters described above ensures that the
resulting fabrics retains characteristics of hand-feel or softness and moisture absorbency
comparable to a pure cotton fabric.
30 [0036] Table 1 below provides fabric construction parameter data for a cottonpolyester blended pile fabric constructed according to the above described parameters.
10
[0037] Table 1
5
10
15 [0038] Table 2 below provides comparative data establishing that in terms of
overall properties, the cotton-polyester blended pile fabric for which fabric construction
parameter data has been provided in Table 1 (and which has been tested under Report
No. TBTL/Devl/2009/00354), and a 100% cotton pile fabric (tested under Report No.
TBTL/Devl/2009/00353) exhibiting substantially similar characteristics, such that the
20 improvement in durability exhibited by the cotton-polyester blend is not offset by any
significant deterioration in other desirable properties.
[0039] Table 2
Table 2
Test Report
Report No. Report No.
TBTL/Devl/2009/00354 TBTL/Devl/2009/00353
Final Comment Satisfactory Satisfactory
Sample Information:
Test Start date 25 August 2020 25 August 2020
Sort No. TG50201699 TG50201698
Customer Guest Supply Guest Supply
Design Embassy/ Micro Poly Embassy/ Nautallt Soft
Shade White White
Size Bath Bath
Physical Test:
Table 1
Sort no TG50201699
Size in cm 70.5 X 146.5
GSM / ( lbs/dz ) 624.5 / ( 17.07 )
Reed/Ends/cm 60 / 11.81
Pick/cm 19.50
Pile height mm 6.25
Pile Count Nec 1/14 Cotton MICRO POLY 75:25, 3.2 TM
Ground Count Nec 1/12 KW PC 50:50
Weft Count Nec 1/12 KW PC
11
Test Actual Result Actual Result
Initial Dimension
(in cms):
Initial Length 148.2 149.00
Initial width 69.7 70.05
Weigh/PcASTM D 3776
Weight/Pcs in gms 634.0 633.0
Dimensional StabilityAATCC 135/150 @ 3
HL (Home Laundry)
Length Shrinkage% -1.38 -1.68
Width Shrinkage% -1.15 -0.86
Lint Loss% (after 3
HL) 0.15 0.18
Dimensional StabilityAATCC 135/150 @ 25
HL
Length Shrinkage% -2.98 -2.15
Width Shrinkage% -1.72 -1.50
Dimensional StabilityAATCC 135/150 @ 50
HL
Length Shrinkage% -3.10 -3.10
Width Shrinkage% -2.49 -2.30
Dimensional StabilityAATCC 135/150 @ 75
HL
Length Shrinkage% -3.80 -4.10
12
Width Shrinkage% -2.98 -3.10
[0040] It has further been discovered that by constructing fabrics comprising a
blend of cotton and polyester fibers in a manner so as to conform to the above described
parameters, the resulting fabric exhibits:
5
• improved strength and durability when compared to 100% cotton fabrics
• reduced flexural rigidity when compared to conventional fabrics manufactured
using cotton-polyester blended yarns
10
• improved moisture absorption, moisture wicking and transportation resulting
from an increase in the number of thin gaps found between individual fibers
within the cotton-polyester blended yarn within the fabric, when compared to
conventional fabrics manufactured using cotton-polyester blended yarns
15
• improved evaporation of moisture as a result of improved wicking
[0041] Table 3 below provides comparative data representing characteristics of
cotton-polyester blends that conform to the above described parameters, wherein the
20 value of ‘f’ is respectively 1.4, 1.2, 0.9 and 0.6, characteristics of a fabric comprising 100%
coarse cotton fiber, and characteristics of fabric comprising 100% fine cotton fiber. It will
be noted that as the ‘f’ value decreases, the flexural rigidity of the resulting blended yarn
or resulting fabric decreases, leading to a softer and improved hand feel.
25 [0042] Table 3
Table 3
Parameter
Polyester
Fiber
Denier
f = 1.4
Polyester
Fiber
Denier
f = 1.2
Polyester
Fiber
Denier
f = 0.9
Polyester
Fiber
Denier
f = 0.6
Cotton -
coarse fiber
Micronaire (4.5
microgram/
inch)
Cotton - Fine
fiber
Micronaire (3.0
microgram/
inch)
‘f' value 1.4 1.2 0.9 0.6 1.60 1.06
13
Fineness in
ref to
conventional
cotton 4.5
Mic as %
88% 75% 56% 37% 100% 67%
Diameter in
Micron 12.1 11.2 9.7 7.9 NA NA
Flexural
rigidity (X
10-3 dynecm2)
5.04 3.87 2.28 1.1
No. of fiber
in cross
section with
100%
content in
14 Ne Yarn
271.2 316.4 421.8 632.7 237.9 356.9
No. of fiber
in cross
section with
25% poly/
75% cotton
content in
14 Ne Yarn
67.79 79.09 105.46 158.18 178.43 267.65
[0043] It has also been discovered that as the as the ‘f’ value decreases, the twist
(i.e. the twist-per-inch parameter) required for spinning the blended yarn also reduces,
5 leading to further improvements in softness and hand feel.
[0044] The invention additionally provides a novel and inventive method for
constructing a fabric that conforms to the parameters described in detail above.
10 [0045] Figure 3 illustrates the method steps involved in manufacturing a
polyester- cotton blended fabric according to the present invention.
[0046] The method can be understood as comprising (i) a first (pre-blend) stage
comprising steps 302a to 308a for a cotton feedstock and steps 302b to 308b for a
15 polyester feedstock, both running in parallel, and (ii) a second (blending an post-blend
stage) where the outputs from the first stage are blended and processed further for
manufacturing a fabric.
14
[0047] The first pre-blend stage comprises processing a first cotton feedstock at
steps 302a to 308a to produce cotton slivers for the subsequent blending stage. The
cotton slivers are prepared starting with cotton fibers (for example cotton fibers from
5 one or more compacted cotton bales). The cotton fibers are processed through a blow
room, carding, a draw frame, a lap former machine and combers, to produce cotton
slivers.
• Step 302a comprises the step of cotton issuance – wherein appropriately selected
10 compacted cotton bales are provided for processing into cotton slivers. Cotton
batch stocks having specific cotton batch number(s) are issued from a warehouse
and transported to the production floor for further processing.
• Step 304a comprises subjecting the cotton fibers to a blow room process wherein
15 the cotton fibers from the bale are opened, cleaned, made free of contamination
and uniformly mixed, before being sent onward to a carding machine for further
processing. In this step 304, cotton bales (highly compacted cotton) received at
step 302a are subjected to blow room processing, where highly compact bales are
opened out into small tufts and cleaned to remove impurities and contaminations.
20 Different machines operating in series within the blow room, open and clean the
cotton – gradually moving from coarse to fine cotton. For contamination cleaning
there are special machines which continuously scan the opened cotton and
separate the contaminants (material other than cotton / plant particles like,
colored fabric, thread, plastic puches, feather etc.) from the cotton. The process
25 step of step 304a results in opened and cleaned tufts of cotton. The cleaning
efficiency of a blow room is normally 40-50%, while the clearing efficiency of
contamination clearing processes is normally between 70-80%
• At step 306a the cotton fibers received from the blow room are subjected to a
30 carding process in a carding machine. The carding machine removes neps, short
fibers and remaining impurities in the cotton fiber and forms carded slivers of
cotton. The carded slivers are delivered in carded sliver cans which are then fed
to a draw frame. In the carding process of step 306a, the opened and partially
15
cleaned cotton is processed through a machine called a card / carding machine –
which has fine and dense sharp wire on circular cylinders and strips, named licker
in, cylinder, doffer, Flat. This wire points open the cotton tufts to individual fiber
level and clean impurities among the cotton fibers. The carding process results in
5 a cotton sliver(s) which is continuous rope of cotton fiber, with a specified weight
gm / meter of sliver.
• Thereafter, at step 308a the carded slivers produced from the carding step are
processed through a draw frame (e.g. a breaker / pre-comb draw frame) wherein
10 a plurality of carded slivers are fed at a time (e.g. 6 carded slivers) and are drafted
to one drawn sliver. As a result, the sliver becomes more oriented and parallelized
and the irregularity of the strand is decreased. Step 308a is implemented at a
drawing machine, which is configured to increase the uniformity and
parallelization of material (i.e. cotton fibers) by overlaying thick and thin regions
15 of cotton slivers to generate uniform slivers. The draw frame involves a single
passage for 100% cotton – and the step 308a results in an output sliver which is
more uniform and having fibers that have been substantially parallelized.
• The slivers drafted through the draw frame at step 308a may be further processed.
20 This further processing involves two different options. In a first option, if the
objective is to produce carded yarn, the slivers drafted through the draw frame at
step 308a can be processed without a lap forming machine and a comber machine
– and the slivers drafted through the draw frame at step 308a passes directly to
step 314. In a second option, if the objective is to produce combed yarn, the slivers
25 drafted through the draw frame at step 308a are passed through a lap forming
machine at step 310a and through a combing machine at step 312a.
• At step 310a, the drawn sliver from the draw frame at step 308a (or from the
combing machine at step 312a) is processed at a lap former machine (e.g. a UNIlap
30 machine) wherein the received are converted into laps by being doubled and
drafted together. The UNIlap machine is configured to prepare cotton material in
a sheet form for a comber machine. The UNIlap machine receives cotton slivers
16
and outputs lap, which is in sheet form with a specified weight gm / meter of 62-
80.
• at step 312a, the laps formed at the lap former machine at step 310a are processed
5 in a comber machine. In a comber machine the material in sheet form from step
310a is presented to a circular cylinder having wire points of different density and
a top comb (having sharp needles) which combs the material, subsequently takes
out the short fibers (e.g. fibers having length < 12.7 mm) and reduces neps in the
material. The output from this step is more uniform, has an optimized or better
10 length of material in sliver form with a specified weight gm/ meter. The comber
machine combs out the lap and removes any kind of neps, short fiber or other
impurities present in it. It also parallelizes the strand. In a preferred embodiment,
the comber delivered cotton hank is manufactured according to the desired
blended yarn parameters – and in an embodiment may be 5.36 gm/m.
15
[0048] In parallel (but not necessarily simultaneously), the pre-blend stage
comprises processing of a second polyester feedstock at steps 302b to 308b to produce
polyester slivers for the subsequent blending stage. The polyester slivers are prepared
starting with polyester fibers (for example polyester fibers from one or more compacted
20 bales). The polyester fibers are processed through a blow room, carding, a draw frame, a
lap former machine and combers, to produce polyester slivers.
• Step 302b comprises the step of polyester issuance – wherein appropriately
selected polyester bales are provided for processing into polyester slivers. Baless
25 of polyester fiber (in highly compressed form) of a specified polyester fiber denier
and quality are issued from a warehouses and are transported to the production
floor for further processing. In a particular embodiment, the polyester fibers
comprise a polyester staple fiber having a fineness of between 0.6 Denier and 1.0
Denier
30
• Step 304b comprises subjecting the polyester fibers to a blow room process
wherein the polyester fibers from the bale are opened, and cleaned before being
sent onward to a carding machine for further processing. The blow room process
17
seeks to open up the polyester fibers from the compressed form. Since polyester
fibers are man-made / artificial fibers, there are no impurities or contaminants
that need to be removed (in contrast to the blow room process for cotton fibers),
and the process therefore needs a relatively fewer number of machines in series.
5 The output of this process step is fully opened tufts of polyester fiber. In a
preferred embodiment, involving polyester fibers having finer deniers of between
0.6 and 1.0 denier, special processing speeds are necessary to achieve required
quality levels – and in a preferred embodiment, the polyester is processed in a
blow room at a speed of approximately 200 kg/hr.
10
• At step 306b the polyester fibers received from the blow room are subjected to a
carding process in a carding machine. The carding machine removes neps, short
fibers and forms carded slivers of polyester. The carded slivers are delivered in
carded sliver cans which are then fed to a draw frame. In this step opened tufts of
15 polyester fibers are further opened at the individual fiber level. As there are no
impurities in material, the purpose of this step is better opening of the previously
compressed polyester fibers. As a result, the carding machine has special wire
points on the card machine component (for example, as per the specifications in
Table 4 below) and along with these specifications of wire, gauge, (distance
20 between) 2 wire points / component need to be selected specifically with the
speed to ensure fibers are not damaged. The output of this step is a sliver of
polyester fiber having a specified weight gm / meter.
In an embodiment, polyester fibers are carded with a delivery speed of 20 kg / hr,
25 and a hank (Nec) of sliver of 0.087 or 6.8 gm/meter. It will be understood that
controlling the wire point specification (including wire point density and wire
point angle) are critical to proper processing of the polyester fiber and to obtain
the right quality of polyester fiber. Table 4 below illustrates exemplary wire point
specifications for controlling the carding process of step 306b.
30
35
18
Table 4
5
10
15
20
25
30
• In a preferred embodiment, the polyester fiber is carded within a carding machine
35 operating at a flat speed of 220 mm/min, and at a cylinder speed of 320
revolutions per minute (rpm) and with the licker-in operating at 700 rpm.
Thereafter, at step 308b the carded slivers produced from the carding step are
processed through a draw frame (e.g. a breaker / pre-comb draw frame) wherein
40 a plurality of carded slivers are fed at a time (e.g. 6 carded slivers) and are drafted
to one drawn sliver. As a result, the sliver becomes more oriented and parallelized
and the irregularity of the strand is decreased. The objective of this step is to make
the polyester fiber is made more uniform and parallel. A draw frame machine may
be used in this process, and in particular, a draw frame with autoleveller function
Table 4
Wire Detail Grade Description
SFL
SFL-90A
SFL-90A-WOSF01ZEA1010-LC300V3-
LCC-ALU.
FD14A S.FLAT-SFD-FD14AF01ZEA7010 LC333-LCC
FD24A S.FLAT-SFD-FD24AF01ZEA7010 LC333-LCC
SFD FD34A S.FLAT-SFD-FD34AF01ZEA7010 LC333-LCC
CYLINDER
WIRE
P2035EX0.4-
METALIC
CYL WIREP2035EX0.4-METALIC-LCC
DOFFER
WIRE N4030Q*0.85R
WIRE-DOFRN4030Q*0.85RF010DQSA47-LCC
LICKER-IN
WIRE D5505X1.20
LI-N WIRE
D5505X1.20-
F010LTD20A-LMW
FLAT TOP 400-S-94-G3 EVO
FLAT TOPSF010TCK094-400-S-94-
G3 EVO-LCC
19
may be utilized to ensure consistent gm / meter through out the length. The output
of this step is a uniform and consistent polyester sliver.
In an embodiment, the polyester sliver is made uniform by processing it through
5 the autoleveller draw frame by doubling 6 ends with a deliver speed of 300 m
/min, and delivered hank of 6.8 gm/m.
[0049] The second stage of the manufacturing process illustrates at steps 314 to
328 (i.e. the blending and post-blend stage) comprises the following:
10
• Step 314 comprises subjecting the combed cotton slivers generated at step 312a
and the draw frame polyester generated at step 308b to a blending process at a
draw frame. At step 314, the blend proportion of cotton and polyester within the
desired yarn is controlled by adjusting the number of slivers of cotton and
15 polyester and the hank of the respective slivers that are used as feedstock input to
the draw frame. In other words, the number of doublings implemented at the draw
frame may be determined based on the cotton and polyester hanks and on the
blend percentage required within the desired blended yarn. For example, 4 ends
of combed cotton and 1 end of polyester may be blended on the draw frame to get
20 a blended yarn comprising 75% combed cotton and 25% polyester. The blending
process at step 314 is implemented using a blending draw frame. Special care may
be taken to ensure that this draw frame has efficient stop motion, which stops the
machine in case any sliver breakage occurs. The output from step 314 is a blended
sliver of cotton / polyester.
25
In an embodiment of step 314, the cotton and polyester sliver feeds to the draw
frame are controlled such that the resulting blended yarn conforms to the
following:
30
5315
C (blended)
×
Wt (polyester)
N(p)
= 𝑓
20
o wherein the variable ‘C (blended)’ represents the count of the blended
yarn comprising both cotton fibers and polyester fibers
5 o wherein the variable ‘Wt (polyester)’ represents the percentage by weight
of polyester fibers within the blended yarn i.e.:
100 ×
Weight of polyester fibers per unit length within the blended yarn)
Total weight of the blended yarn per unit length
10 o wherein the variable ‘N(p)’ represents the number of polyester fibers
included within (or distributed across) the cross-section of the blended
yarn
o and wherein 0.6 ≤ 𝑓 ≤ 1.0
15
• The blended sliver from step 314 is thereafter subjected to a draw frame levelling
process at step 316 - wherein the polyester-cotton blended sliver is passed
through one or more draw frame passages to make the blended sliver more
uniform. The draw frame levelling step is implemented at a draw frame machine,
20 and results in a more uniformly blended sliver of cotton and polyester.
• Thereafter, the output from step 316 is passed through a draw frame finisher at
step 318, wherein the draw frame finisher is equipped with an auto-leveller. The
finisher is equipped with an auto‐leveller. The auto‐leveller continuously scans
25 the incoming slivers and increases or decreases the draft in the drafting zone so
as to ensure a blended sliver having a uniform thickness. In an embodiment, the
auto-leveller drawing speed is approximately 450 m / min for pile yarn, the hank
is 0.110 and the sliver unevenness (U%) is less than 2.7%. Step 318 involves
subjecting the blended sliver of cotton and polyester to one or more further draw
30 frame passages to ensure that the blended cotton and polyester material is
homogenously blended together, and is more uniform. An autoleveller draw frame
21
may be used in this step, and the output of step 318 is an uniform, homogenously
blended cotton/polyester sliver.
• At step 320, the output from step 318 is then passed through a speed frame (or a
5 simplex machine). The speed frame reduces the linear density of the blended
sliver by drafting – and produces an intermediate product called the roving. The
roving is wound onto a bobbin – with a small amount of twist being imparted to
the roving during winding. In an embodiment, the hank of the produced roving is
0.6 and the twist multiplier for the roving is between 1.1 and 1.4.
10
• At step 322 the roving from step 320 is passed through a ring frame – which
converts the roving into the desired blended yarn. The objective of step 322 is to
manufacture yarn by (i) drafting the roving into a desired thickness of yarn as per
the count, (ii) twisting the yarn to give yarn sufficient strength, and (iii) winding
15 this yarn on to a ring frame bobbin. In certain embodiments, ring frame machines
are used for this step and one or more of spindle speed, type of ring traveller, and
twist multiplier parameters may be varied to achieve the desired outcome. The
roving obtained at step 322 gets used as input material in the ring frame, and the
actions of drafting, twisting and package formation are performed within the ring
20 frame process – resulting in the output of the desired blended yarn, which is
wound onto ring bobbins. For example, in an embodiment the count of the desired
blended yarn is 14 Nec combed cotton / polyester in a 75-25 blend ratio and the
twist multiplier is selected to the minimum level permitted as per the blend and
ring spinning performance (for example, a twist multiplier of between 2.8 and 4.2,
25 and in a specific embodiment a twist multiplier of 3.2).
• The blended yarn from the ring frame is fed to an autoconer at step 324, wherein
the ring spun yarn is wound into large packages. In this step, small packages of
blended yarn that have been output from the ring frame bobbin (yarn content of
30 35-100 gm) is converted to a bigger package (1.89-2.75 kg). An autoconer machine
is used for this step, which may have an EYC (electronic Yarn clearer) which
continuously scans the yarn and cut in case of any defect, takes that defective yarn
out and joins the yar ends again through a splicer.
22
• At step 326, the blended yarn wound onto cones or into large packages by the
autoconer is woven into a fabric, wherein the blended yarn is used as one or more
of a pile yarn, a warp yarn or a weft yarn, for the purposes of weaving the fabric.
5 In a particular embodiment, the blended yarn manufactured in accordance with
the claimed invention is used as a pile yarn for weaving a pile fabric (such as a
towel fabric or a terry fabric), while the ground and weft yarns for the fabric are
produced according to standard or conventional methods – and may comprise a
cotton yarns or conventional cotton-polyester blends. In another embodiment,
10 where the woven fabric is a sheeting fabric or a flat fabric, the blended yarn
manufactured in accordance with the claimed invention is used as a warp yarn or
a weft yarn or as both.
• Step 328 comprises one or more of pre-treatment, dyeing and finishing steps. In
15 this step, grey fabric goes through desizing, scouring and bleaching, which
removes the starch and other impurities of cotton fiber and makes these fibers
white so that they can absorb the dyeing color more uniformly. After dyeing, the
fabric is passed through a finishing machine where a specially functional finish, or
softener is applied to make it soft and functional. The pre-treatment, dyeing and
20 finishing steps may be followed by cut, stitch and pack processes for generating a
final product.
[0050] In an embodiment, the invention comprises a cotton-polyester blend fabric
comprising (i) a plurality of interwoven yarns, wherein at least one of the interwoven
25 yarns is a blended yarn comprising a plurality of cotton fibers and a plurality of polyester
fibers twisted together, wherein the blended yarn conforms to:
5315
C(blended)
×
Wt (polyester)
N(p)
= 𝑓
30 and wherein:
C(blended) is a count of the blended yarn
23
Wt (polyester) is a percentage by weight of polyester fibers within the blended
yarn
5 N(p) is the number of polyester fibers distributed across the blended yarn’s
cross-section
and 0.6 ≤ 𝑓 ≤ 1.0.
10 [0051] In an embodiment of the invention the polyester fibers within the blended
yarn have a fiber thickness of between 0.6 and 1.0 denier. In another embodiment, the
weight of polyester within the blended yarn (Wt (polyester)) is such that 5% ≤ Wt
(polyester) ≤ 80%.
15 [0052] The blended yarn may have a twist multiplier of between 2.8 and 4.2.
[0053] In an embodiment, the cotton fibers within the blended yarn may have a
fiber thickness of between 3 microgram / inch and 5 Microgram / inch
20 [0054] One or more of a pile yarn, a warp yarn, a ground yarn or a weft yarn within
the fabric may comprise the blended yarn.
In various embodiments the fabric is a pile fabric and, either or both of the ground and
weft yarns may be formed with polyester fibers or without polyester fibers. In a specific
25 embodiment of the invention, (i) the fabric is a pile fabric, (ii) the pile yarn is formed from
the blended yarn, and (iii) the ground yarns and weft yarns have been formed without
polyester fibers. In another embodiment of the invention, (i) the fabric is a pile fabric, (ii)
the pile yarn is formed from the blended yarn, and (iii) one or both of the ground yarns
and weft yarns are formed from the blended yarn.
30
[0055] In various embodiments the fabric is a flat fabric and, one of the ground
and weft yarns is formed from the blended yarn, while the other of the ground and weft
yarns may be formed with polyester fibers or without polyester fibers. In a specific
24
embodiment of the invention (i) the fabric is a flat fabric, and (ii) each of the warp yarn
and the weft yarn within the fabric comprise the blended yarn, or (iii) one of the warp
yarn and the weft yarn within the fabric comprises the blended yarn, and the other of the
warp yarn and the weft yarn has been formed without polyester fibers.
5
[0056] In an embodiment of the invention, the fabric is a towel fabric or a bed linen
fabric.
[0057] The invention additionally provides a cotton-polyester blended yarn for
10 weaving an absorbent fabric, comprising a plurality of cotton fibers and a plurality of
polyester fibers twisted together - wherein the blended yarn conforms to:
5315
C(blended)
×
Wt (polyester)
N(p)
= 𝑓
15 and wherein:
C(blended) is a count of the blended yarn;
Wt (polyester) is a percentage by weight of polyester fibers within the blended
20 yarn
N(p) is the number of polyester fibers distributed across the blended yarn’s
cross-section
25 and 0.6 ≤ 𝑓 ≤ 1.0.
[0058] In an embodiment of the cotton-polyester blended yarn, the polyester
fibers have a fiber thickness of between 0.6 and 1.0 denier. In another embodiment of the
cotton-polyester blended yarn, 5% ≤ Wt (polyester) ≤ 80%. In a further embodiment of
30 the cotton-polyester blended yarn, the blended yarn has a twist multiplier of between 2.8
and 4.2.
25
[0059] The invention also provides a method for manufacturing a cotton-polyester
blend fabric, comprising the steps of: (i) providing a blended yarn comprising a plurality
of cotton fibers and a plurality of polyester fibers twisted together, wherein the blended
yarn conforms to:
5
5315
C(blended)
×
Wt (polyester)
N(p)
= 𝑓
wherein:
10 C(blended) is a count of the blended yarn;
Wt (polyester) is a percentage by weight of polyester fibers within the
blended yarn
15 N(p) is the number of polyester fibers distributed across the blended
yarn’s cross-section
and 0.6 ≤ 𝑓 ≤ 1.0;
20 and (ii) weaving a fabric comprising a plurality of interwoven yarns, wherein the
blended yarn comprises at least one of the interwoven yarns.
[0060] In an embodiment of the method, the polyester fibers polyester fibers have
a fiber thickness of between 0.6 and 1.0 denier.
25
[0061] In another embodiment of the method, the weight of polyester used within
the blended yarn (Wt (polyester)) is such that 5% ≤ Wt (polyester) ≤ 80%.
[0062] In a method embodiment, the blended yarn has a twist multiplier of
30 between 2.8 and 4.2.
26
[0063] The step of weaving the fabric may comprise utilizing the blended yarn to
form any one or more of a pile yarn, a warp yarn, a ground yarn or a weft yarn.
[0064] In various method embodiments, the fabric is a pile fabric and, either or
5 both of the ground and weft yarns may be formed with polyester fibers or without
polyester fibers. In a specific method embodiment, (i) the step of weaving the fabric
comprises weaving a pile fabric, (ii) the blended yarn is a pile yarn, and (iii) the grounds
yarn and weft yarns are formed without polyester fibers.
10 [0065] In various other method embodiments, the fabric is a flat fabric and, either
or both of the warp and weft yarns may be formed with polyester fibers or without
polyester fibers. In a specific method embodiment, (i) the step of weaving the fabric
comprises weaving a flat fabric, and (ii) each of the warp yarn and the weft yarn within
the fabric comprise the blended yarn, or (iii) one of the warp yarn and the weft yarn
15 within the fabric comprises the blended yarn, and the other of the warp yarn and the weft
yarn has been formed without polyester fibers.
[0066] The invention additionally provides a method for manufacturing a cottonpolyester blended yarn for weaving an absorbent fabric, comprising the steps of (i)
20 preparing a blended yarn comprising a plurality of cotton fibers and a plurality of
polyester fibers twisted together, wherein the blended yarn conforms to:
5315
C(blended)
×
Wt (polyester)
N(p)
= 𝑓
25 wherein:
C(blended) is a count of the blended yarn
Wt (polyester) is a percentage by weight of polyester fibers within the
30 blended yarn
27
N(p) is the number of polyester fibers distributed across the blended
yarn’s cross-section
and 0.6 ≤ 𝑓 ≤ 1.0.
5
[0067] In an embodiment of the method for manufacturing the cotton-polyester
blended yarn, the polyester fibers polyester fibers have a fiber thickness of between 0.6
and 1.0 denier. In a further embodiment of this method 5% ≤ Wt (polyester) ≤ 80%. In
a particular method embodiment, the blended yarn is imparted with a twist multiplier of
10 between 2.8 and 4.2.
[0068] While the exemplary embodiments of the present invention are described
and illustrated herein, it will be appreciated that they are merely illustrative. It will be
understood by those skilled in the art that various modifications in form and detail may
15 be made therein without departing from or offending the spirit and scope of the invention
as defined by the appended claims. Additionally, the invention illustratively disclose
herein suitably may be practiced in the absence of any element which is not specifically
disclosed herein – and in a particular embodiment that is specifically contemplated, the
invention is intended to be practiced in the absence of any one or more element which
20 are not specifically disclosed herein.

We Claim:
1. A cotton-polyester blend fabric comprising:
5 a plurality of interwoven yarns, wherein at least one of the interwoven yarns is a blended
yarn comprising a plurality of cotton fibers and a plurality of polyester fibers twisted
together;
wherein the blended yarn conforms to:
10
5315
C(blended)
×
Wt (polyester)
N(p)
= 𝑓
and wherein:
15 C(blended) is a count of the blended yarn;
Wt (polyester) is a percentage by weight of polyester fibers within the blended
yarn
20 N(p) is the number of polyester fibers distributed across the blended yarn’s
cross-section
and 0.6 ≤ 𝑓 ≤ 1.0.
25 2. The fabric as claimed in claim 1, wherein the polyester fibers within the blended
yarn have a fiber thickness of between 0.6 and 1.0 denier.
3. The fabric as claimed in claim 1, wherein 5% ≤ Wt (polyester) ≤ 80%.
30 4. The fabric as claimed in claim 1, wherein the blended yarn has a twist multiplier
of between 2.8 and 4.2.
29
5. The fabric as claimed in claim 1, wherein one or more of a pile yarn, a warp yarn,
a ground yarn or a weft yarn comprise the blended yarn.
5
6. The fabric as claimed in claim 5, wherein:
the fabric is a pile fabric;
10 the blended yarn is a pile yarn; and
the ground yarns and weft yarns have been formed without polyester fibers.
7. The fabric as claimed in claim 5, wherein:
15
the fabric is a pile fabric;
the pile yarn and one or both of the ground yarns and weft yarns are formed from the
blended yarn.
20
8. The fabric as claimed in claim 5, wherein:
the fabric is a flat fabric; and
25 each of the warp yarn and the weft yarn within the fabric comprise the blended
yarn; or
one of the warp yarn and the weft yarn within the fabric comprises the blended
yarn, and the other of the warp yarn and the weft yarn has been formed without
30 polyester fibers.
9. The fabric as claimed in claim 1, wherein said fabric is a towel fabric or a bed linen
fabric.
30
10. A cotton-polyester blended yarn for weaving an absorbent fabric, comprising:
a plurality of cotton fibers and a plurality of polyester fibers twisted together;
5
wherein the blended yarn conforms to:
5315
C(blended)
×
Wt (polyester)
N(p)
= 𝑓
10 and wherein:
C(blended) is a count of the blended yarn;
Wt (polyester) is a percentage by weight of polyester fibers within the blended
15 yarn
N(p) is the number of polyester fibers distributed across the blended yarn’s
cross-section
20 and 0.6 ≤ 𝑓 ≤ 1.0.
11. The blended yarn as claimed in claim 10, wherein the polyester fibers have a fiber
thickness of between 0.6 and 1.0 denier.
25 12. The blended yarn as claimed in claim 10, wherein 5% ≤ Wt (polyester) ≤ 80%.
13. The blended yarn as claimed in claim 10, the blended yarn has a twist multiplier
of between 2.8 and 4.2.
30 14. A method for manufacturing a cotton-polyester blend fabric, comprising the steps
of:
31
providing a blended yarn comprising a plurality of cotton fibers and a plurality of
polyester fibers twisted together, wherein the blended yarn conforms to:
5315
C(blended)
×
Wt (polyester)
N(p)
= 𝑓
5
wherein:
C(blended) is a count of the blended yarn;
10 Wt (polyester) is a percentage by weight of polyester fibers within the
blended yarn
N(p) is the number of polyester fibers distributed across the blended
yarn’s cross-section
15
and 0.6 ≤ 𝑓 ≤ 1.0;
weaving a fabric comprising a plurality of interwoven yarns, wherein the blended yarn
comprises at least one of the interwoven yarns.
20
15. The method as claimed in claim 14, wherein the polyester fibers polyester fibers
have a fiber thickness of between 0.6 and 1.0 denier.
16. The method as claimed in claim 14, wherein 5% ≤ Wt (polyester) ≤ 80%.
25
17. The method as claimed in claim 14, wherein the blended yarn has a twist
multiplier of between 2.8 and 4.2.
18. The method as claimed in claim 14, wherein the step of weaving the fabric
30 comprises utilizing the blended yarn as any one or more of a pile yarn, a warp yarn, a
ground yarn or a weft yarn.
32
19. The method as claimed in claim 18, wherein:
the step of weaving the fabric comprises weaving a pile fabric;
5 the blended yarn is a pile yarn; and
the ground yarns and weft yarns have been formed without polyester fibers.
20. The method as claimed in claim 18, wherein:
10
the step of weaving the fabric comprises weaving a pile fabric;
and the pile yarn and one or both of the ground yarns and weft yarns are formed from
the blended yarn.
15
21. The method as claimed in claim 19, wherein:
the step of weaving the fabric comprises weaving a flat fabric; and
20 each of the warp yarn and the weft yarn within the fabric comprise the blended
yarn; or
one of the warp yarn and the weft yarn within the fabric comprises the blended
yarn, and the other of the warp yarn and the weft yarn has been formed without
25 polyester fibers.
22. A method for manufacturing a cotton-polyester blended yarn for weaving an
absorbent fabric, comprising the steps of:
30 preparing a blended yarn comprising a plurality of cotton fibers and a plurality of
polyester fibers twisted together, wherein the blended yarn conforms to:
33
5315
C(blended)
×
Wt (polyester)
N(p)
= 𝑓
wherein:
C(blended) is a count of the blended yarn;
5
Wt (polyester) is a percentage by weight of polyester fibers within the
blended yarn
N(p) is the number of polyester fibers distributed across the blended
10 yarn’s cross-section
and 0.6 ≤ 𝑓 ≤ 1.0.
23. The method as claimed in claim 22, wherein the polyester fibers polyester fibers
15 have a fiber thickness of between 0.6 and 1.0 denier.
24. The method as claimed in claim 22, wherein 5% ≤ Wt (polyester) ≤ 80%.
25. The method as claimed in claim 22, comprising imparting the blended yarn with a
20 twist multiplier of between 2.8 and 4.2.