Note: Descriptions are shown in the official language in which they were submitted.
CA 02352709 2001-07-24
s x
TITLE OF THE INVENTION
INSTITUTIONAL TOWEL
FIELD OF THE INVENTION
This invention relates to a process for the manufacture of institutional
towels with the
resulting towel having a much longer life expectancy.
BACKGROUND OF THE INVENTION
It is well known to manufacture towels in a process utilizing yarn spun from
100%
cotton fibres. In manufacturing such a towel, the yarn is woven, as is well
known, on a
loom with the 100% cotton yarn being contained in the ground, fill, and pile
yarns. In
fact it is the 100% cotton aspect of the towel that makes it more "desirable"
by the
consumer since it is fixed in the mind of the purchaser that 100% cotton
towels are more
absorbent than other types of towels. However, when considering an
institutional
towel there are many drawbacks to providing 100% cotton spun yarns woven into
towels since there are other issues which must be considered, which from an
institutional standpoint creates disadvantages to the institution, for example
a hotel
chain.
CA 02352709 2001-07-24
Page 2
In manufacturing a typical towel through a continuous process, the towel is
woven
from the yarns accumulated on beams with the output from the loom being a
continuous web of interconnected toweling product which must be bleached to
remove
any materials applied during the slashing process including a washing step.
The
toweling products are subsequently dyed through a cold pad batch or beck dying
process, washed and finally dried, then separated and finished into towels, or
other
terry products.
The output therefore from the process includes towels of different colours
including
white, and various other shades. For a towel or a towel product for the retail
market,
the consumer is quite content to wash the coloured towels without bleaching
and to
apply a fabric softener either in the wash or in the dryer.
However, with institutional towels the concerns for the life expectancy of the
towel
becomes very important. Institutional towels are washed with bleach time after
time
and as a result it can be expected that the colour will fade after as little
as ten washings
with the colour being substantially gone after twenty washings. This is quite
costly for
the industry and therefore as a rule most institutional towels are white. By
selecting a
white colour, the towels may be washed over and over without the risk of
fading.
Further coloured institutional towels will fade, even without bleach, and will
become
unacceptable before they wear out.
CA 02352709 2002-09-06
Page 3
It is known in the patent literature to provide a towel construction wherein
it is
suggested that yarns for ground fill, ground warp and the pile warp, although
preferably being made of cotton, may also be manufactured from yarns made of
blends
of cotton and polyester. For example, United States Patent No. 4,726,400
describes this
alternative. It is also discussed within United States Patent No. 4,726,400
that a
checkered pattern may be provided in the terry cloth by utilizing different
colour yarns.
There is no discussion however as to how the yarns might be manufactured and
coloured. We are also aware of other constructions for towels, for example
United
States Patent No. 3,721,273 discusses in the Background of the Invention a
preference of
cotton and alternatively that synthetic fibres may be blended with the cotton
fibres.
Rayon yarns are also discussed in relation to their absorbency in that the
rayon may be
woven into the towel in the form of a 3-pick terry weave. United States Patent
No.
3,721,272 discusses that terry yarns have been formed of shrinkable synthetic
fibres
blended with cellulosic fibres, such as cotton. United StatE~s Patent No.
3,721,274
teaches a woven terry towel wherein the ground warp and/or the filling yarns
are
composed of a blend of polyester and cellulosic fibres, but the terry pile is
manufactured from 100°/~ cotton. Within the reference is it stated that
polyester has
beEn heretofore considered an undesirable fibre for use in terry towels due to
its low
moisture absorbency characteristics. In fact, United States Patent No.
6,062,272 issued
May 16, 2000 teaches an all cotton pile with polyester being in the ground
fabric. The
pile yarns although desirably all cotton may include small quantities of other
fibres
such as polyester or rayon which would result in a corresponding decrease in
the
CA 02352709 2001-07-24
Page 4
absorbency of the finished towel product. Specifically in the examples various
compositions are described.
However, in spite of the general discussions in the above-mentioned patent
literature
there is no discussion of the present problems facing the institutions which
purchase
institutional towels. The towels used in for example, the hotel industry are
generally
white and if not white then they will be rendered unusable in twenty washing
cycles.
This is highly undesirable since most institutions bleach their laundry
including towels
for health reasons and would prefer to present the hotel guests with an
attractive set of
towels which have an unique colour and which colour match one another, other
than a
white set of towels.
It is therefore a primary object of this invention to provide an institutional
towel and
toweling products which are coloured and yet which are colour-fast.
It is a further object of this invention to provide an institutional towel and
toweling
product which is the result of a manufacturing process resulting in minimum
variation
from batch to batch of the final product colour.
It is a further object of this invention to provide an institutional towel
that has a
significantly longer life expectancy.
CA 02352709 2001-07-24
Page 5
It is a further object o f this invention to provide an institutional towel
ensemble which
includes a matching set of toweling products having very little colour
variation from
item to item.
It is a further object of this invention to provide a process of manufacturing
an
institutional towel which eliminates the need to dye the towel at the towel
mill.
Further and other objects of the invention may become apparent to those
skilled in the
art when considering the following summary of the invention and a more
detailed
description of the preferred embodiments illustrated herein.
SUMMARY OF THE INVENTION
According to a primary aspect of the invention there is provided a process for
manufacturing toweling products comprising the steps of:
1) Providing cotton fibres;
2) Providing pre-dyed polyester fibres;
3) Orienting the fibres of the cotton in substantially a uniform parallel
direction by
carding;
4) Orienting the pre-dyed polyester fibres in substantially parallel direction
by a
carding process;
CA 02352709 2001-07-24
Page 6
5) Draw blending the cotton and pre-dyed polyester fibres in a slivering
process
preferably in a ratio of 8 to 14% of the pre-dyed polyester fibres with the
balance
being the cotton fibre;
6) Following the intimate draw blending of the pre-dyed polyester and cotton
fibres
spinning the slivered fibres into twisted yarns having a pre-determined colour
which will be imparted to the toweling product;
7) Accumulating the yarns on a loom beam following warping/slashing the yarns
in preparation for the weaving process;
8) Weaving said coloured yarn into the ground warp, the fill and the pile warp
yarns in the toweling product which preferably is a continuous process;
9) Preferably bleaching and subsequently washing and drying said toweling
product prior to finishing;
wherein the colour in the toweling product is obtained by the weaving process
only with no subsequent dying process being necessary and wherein the
resulting towel products have
i) a minimum colour variation from batch to batch,
ii) are colour fast, the colour being imparted to the toweling product by the
pre-
dyed polyester fibre allowing all institutional towels resulting from this
process to be able to be washed and handled together,
iii) a significantly longer life expectancy of the towel imparted by the
polyester
fibre, and
CA 02352709 2001-07-24
Page 7
iv) the ability of the toweling product to be manufactured into a matching set
of
toweling products having minimum colour variation from product to
product.
The resulting institutional towel from this process overcomes many of the
deficiencies
and problems experienced in the institutional towel industry having a severe
limitation
in terms of white only in order to minimize the handling problem which would
result
should colours have to be separated.
In relation to life expectancy it has been, through experimentation, proven
that such a
towel manufactured for experimental purposes has undergone 100 washes with
bleaching, but it has not lost it's luster and has not faded in spite of
having been
bleached. The towel was manufactured from the drawn blend yarn of a vanilla
colour.
The colour therefore in the institutional towel has been imparted to it by
spinning yarns
of a drawn blend of pre-dyed polyester fibres and natural cotton fibres. The
resulting
towel therefore is colour-fast, as a result, many times over those towels dyed
in
conventional manners. Typically as discussed in the background towels may be
washed twenty times before one might expect the colour to be significantly
altered. The
experimental towels produced did not fade and retained their luster through
100 wash
cycles.
CA 02352709 2001-07-24
Page 8
According to yet another aspect of the invention there is provided an
institutional
coloured towel (and preferably manufactured from the above-mentioned process)
which comprises coloured yarns draw blended of a pre-determined amount of pre-
dyed
polyester fibre with the remainder being natural cotton fibres resulting in a
yarn of pre-
determined colour, said toweling product having ground warp, fill, and terry
loop
fibres manufactured from said yarn resulting in said institutional towel
having a pre-
determined colour which is colour fast, has little variance from lot to lot,
may be
washed and bleached, is conveniently handled by an institution, has an
increased life
expectancy imparted by the polyester, and which has reproducible colour of the
finished towel product from batch to batch.
It is therefore expected that other colours other than a vanilla colour
obtained with the
12.5% brown pre-dyed polyester fibre may also be manufactured. Pastel shades
of blue,
red, green or the like may be manufactured in the form of an institutional
towel which
is superior when compared to known institutional towels of all cotton
construction in
terms of convenience and handling through the washing and bleaching cycles
with the
resulting increase in life expectancy while maintaining its colour and luster.
The colour
is reproducible from batch to batch and from product to product so that
complete bath
ensembles can be provided to the institution with matching colours from the
face cloth,
the bath towel and the hand towel and the bath mats.
CA 02352709 2001-07-24
Page 9
According to yet another aspect of the invention there is provided a method of
colouring a towel, and preferably an institutional towel, comprising weaving
said towel
from twisted yarn spun from an intimate, drawn blend of a predetermined amount
of
pre-dyed polyester fibre, preferably in the range of 8-14%, with the balance
being cotton
fibre, said coloured yarn thereafter being spun from said drawn blend and all
of said
ground yarns, fill yarns and pile yarns making up said towel being formed from
said
drawn blended twisted coloured yarn to form said institutional towel which has
the
properties of: 1) being colourfast; 2) being consistent in colour from batch
to batch; 3)
being consistent in colour from towel product type to towel product type, for
example,
for a bath towel, face towel, wash cloth, and bath mat; 4) being capable of
being
bleached and washed without fading or loosing it's luster; and 5) having an
extended
life expectancy.
According to yet another aspect of the invention there is provided a towel and
preferably an institutional towel, preferably manufactured from the above
method
comprising twisted yarn spun from an intimate, drawn blend of a predetermined
amount of pre-dyed polyester fibre, preferably in the range of 8-14%, with the
balance
being cotton fibre, said coloured yarn thereafter being spun from said drawn
blend and
all of said ground yarns, fill yarns and pile yarns making up said towel being
formed
from said drawn blended twisted coloured yarn to form said institutional towel
which
has the properties of: 1) being colourfast; 2) being consistent in colour from
batch to
batch; 3) being consistent in colour from towel product type to towel product
type, for
CA 02352709 2001-07-24
Page 10
example, for a bath towel, hand towel, wash cloth, and bath mat; 4) being
capable of
being bleached and washed without fading or loosing it's luster; and 5) having
an
extended life expectancy.
The aspect of providing a colour within an institutional towel is a
considerable
improvement for the hotel industry which no longer will be required to supply
bland
white towels or run the risk of having considerable expense if coloured towels
are
selected. By providing a towel by the above-mentioned method any pastel shade
of
towel can be manufactured including vanilla, pink, light blue, light green,
grey and any
other pastel type of shade without sacrificing a great deal of absorbency in
the towel. It
is considered that the advantages of such an institutional towel or for that
matter a
coloured towel in the retail trade are more than offset by the minimal loss in
absorbency.
According to another aspect of the invention there is provided a coloured
institutional
towel comprising ground warp, fill, and pile warped yarns, all of said yarns
being
coloured by intimately draw blending a predetermined amount of pre-dyed
polyester
fibre with cotton fibre when the yarn is spun and twisted to thereby form a
predetermined colour for the institutional towel.
For a preferred vanilla towel the twisted yarn includes a predetermined amount
of
predyed polyester fibre having a predetermined denier, and tenacity and fibre
length.
CA 02352709 2001-07-24
Page 11
No limitations however to these variables is contemplated for use in the
institutional
towel. For the vanilla towel the predyed polyester fibre has a beige colour
but as
discussed it may have a different colour depending on the shade of towel
desired. The
colour of the predyed polyester is established by trial and error, and
specified by a
matching comparison with a coloured swatch. The predyed polyester/cotton draw
blended twisted yarn is manufactured with a predetermined twist (turns per
inch) in
the yarn. The ground and fill yarns may or may not have substantially the same
twist
as the pile yarns although they are of course of the same colour.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a flow chart of the Process of Manufacture of the present
invention utilized
in the manufacture of the Institutional Towel thereof.
Figure 2 is a schematic perspective view of the towel product manufactured
from the
process steps of Figure 1.
Figure 3 is a close up perspective view of the yarn elements and how they are
woven
into the terry product illustrated in Figure 2.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
CA 02352709 2001-07-24
Page 12
Referring to Figure 1, a process flow chart is illustrated which describes the
manner in
which the Institutional Towel is manufactured. The towel product (5) therefore
of
Figure 2 is manufactured so as to overcome many of the deficiencies in prior
institutional towels. As discussed in the Background of the Invention, most
institutional towels are white because otherwise they would not stand up to
the
washing and bleaching cycles. It is appreciated that a towel product in a
hotel, for
example, would be washed on a daily basis. Should these towels and various
towel
products such as wash cloths, hand towels, bath towels, bath mats, bath robes,
etc. be
coloured, as is desirable, then they would have to be sorted out from the
regular
laundry flow and could not be subjected to bleaching. However, if they are not
sorted
then these toweling products would not stand up and the colour would fade by
approximately 20 cycles.
Therefore, to address this problem, the present invention provides an
Institutional
Towel that is preferably vanilla in colour but may be other pastel shades such
as grey,
light blue, light green, yellow or the like. The toweling product formed by
carrying out
the process of Figure 1 will have the preferred vanilla colour and will have
very little
shade variance from batch to batch of towels, and from batch to batch of
matching
toweling products making up a bath assemble. This minimum variation from batch
to
batch and from toweling product to toweling product is important especially
after
many washing cycles. It is desirable that the product stand up to the rigors
of such
washing and bleaching cycles and yet not fade, yet still matching the colour
for the bath
~ . , CA 02352709 2001-07-24
Page 13
mat, bath towel, face towel, and wash clothes. It is also a result of this
invention that
the product is coloured without the necessity of carrying out a dying process
at the
towel mill. The resulting towel product stands up to many, many washings
because of
the extra strength imparted to the yarns by the presence of polyester. The
polyester is
distributed throughout the towel having been blended with cotton in
manufacturing
the yarn and therefore this strength and resilience of the product is
distributed
throughout all of the yarns including the ground, fill and pile yarns.
Referring to Figure 1, the polyester is purchased in raw fibre form, with the
fibres
having been pre-dyed in this example to a brown colour, which when blended
with the
cotton fibres will result in a yarn having a vanilla colour. The materials are
received in
bales and the fibres are somewhat compacted as received. The fibres therefore
must be
separated sufficiently so as to be able to be properly handled. As is known,
the cotton is
cleaned. Once the fibres have been broken down in the sense that they have
been
separated and the bulk density thereof has been drastically reduced, they are
in the
form that they can be passed through a carding machine in order to take the
fibres that
are randomly distributed in the pre-dyed polyester and the cotton and to
orient them in
a generally parallel direction. The result of the carding process is that the
fibres are laid
out in a parallel direction in a long extended, untwisted rope like element.
This is the
case with both the pre-dyed polyester and the cotton. The continuous filaments
therefore, having been carded are then accumulated to be fed through a
slivering
machine, and is utilized to create an intimate draw blend of the cotton and
pre-dyed
. , , CA 02352709 2001-07-24
Page 14
polyester carded fibres. The products are slivered together, that is to say
draw blended,
at a ratio of between 8 to 14% polyester, and the remainder being cotton. The
resulting
slivered element is continuous and is of considerable larger diameter than the
prior
carded products. The slivered continuous elements are therefore accumulated
and fed
into a yarn spinning machine, and the yarn product is spun from the intimately
draw
blended slivered mixture of polyester and cotton. The resulting twisted yarn
is then
accumulated again and processed through a warping/slashing process and coated
with
a compound to enable the yarn to stand up and impart to it a certain robust
quality
required during the weaving process. The yarn is therefore accumulated on a
beam and
fed to a loom for the toweling product to be manufactured. The ground yarn,
the fill
yarn and the pile yarns are all manufactured from the same coloured yarn
intimately
draw blended to provide the preferred vanilla colour. The resulting towel
products are
therefore finished and prepared for distribution, once the towels have been
washed in
caustic and bleached to remove the coating compound and dried to enable
finishing.
The resulting toweling products therefore have all of the desired qualities of
the
institutional towel product previously discussed with an unexpectedly much
longer
extended life than what might have been expected from the use of a draw
blended yarn
product that is pre-coloured. The towel product is therefore coloured without
the
necessity of including the dye step in the towel manufacturing process and the
handling
of chemicals required in order to do so. The safety within the mill therefore
is enhanced
and the product has proven by experimentation to be much superior to
previously
known institutional towels and towel products.
CA 02352709 2001-07-24
Page 15
The coloured towel product (5) is illustrated in Figure 2 with the preferred
three pick
weaving step shown in close up in Figure 3 with all of the yarns shown in
Figure 3
therefore including the vanilla colour draw blended twisted yarn previously
manufactured at the yarn mill. The towel product therefore includes the pile
coloured
yarns (20) the ground coloured yarns (30) and the fill coloured yarns (40)
which are
woven in a manner as is well known on a loom. All of the yarns are those which
have
a vanilla colour and contain an intimate draw blend of polyester and cotton.
The
coloured towel product preferably includes 75 threads per inch for the pile
yarn, 60
threads per inch for the fill yarn and 45 threads per inch for the ground
yarns. Up to
three pile picks may be woven between two adjacent weft yarns of ground
fabric. The
result is a towel without an increase in the amount of polyester therein, but
a different
significant distribution which imparts the significant advantages identified
above.
For the preferred vanilla towel (5) the twisted yarn (20, 30, 40) includes a
predetermined
amount of predyed polyester fibre having a predetermined denier, and tenacity
and
fibre length. No limitations however to these variables is contemplated for
use in the
institutional towel. For the vanilla towel (5) the predyed polyester fibre has
a beige
colour. The colour of the predyed polyester is established by trial and error,
and
specified by a matching comparison with a coloured swatch. The predyed
polyester/cotton draw blended twisted yarn (20, 30, 40) are manufactured with
a
predetermined twist (turns per inch) in the yarns. The ground and fill yarns
(30, 40)
.. ~ CA 02352709 2001-07-24
Page 16
may or may not have substantially the same twist as the pile yarns (20)
although they
are of course of the same colour.
As many changes can be made to the preferred embodiment of the invention
without
departing from the scope thereof; it is intended that all matter contained
herein be
considered illustrative of the invention and not in a limiting sense.
