A New Method of Treating Cotton to Give it the Glossy Appearance of Silk.
Year: 1898

page_text: Date of Application, 7th Dec., 1898
Complete Specification Left, 10th Mar., 1899-Accepted, 29th Apr., 1899
PROVISIONAL SPECIFICATION.
A New Method of Treating Cotton to Give it the Glossy Appearance
of Silk.
We, FERNAND GROS and PAUL BOURCART, of Remiremont, Vosges, in the French
Republic, Spinners, do hereby declare the nature of this invention to be as
follows:-
At the present time the name mercerization designates the series of operations
the result of which is to give cotton a glossy appearance similar to that of silk,
this result being obtained by subjecting the threads or fabrics of cotton to severe
tensile strain, and whilst in this condition to the action of certain chemical
agents, particularly caustic alkalis. Hitherto good results have been obtained
only with the threads arranged in special ways and particularly with spun or
twisted threads, that is to say strands or threads composed of several threads or
fibres spun or twisted together. But hitherto the lustrous or glossy condition has
not been obtained suitably or conveniently with single threads or other spinning
material. This is due to the fact that these threads do not give sufficient resistance
to withstand the tensile strain to which they must be subjected when under tho
action of the chemical agents. Moreover after the operation they are frequently
found to be surrounded by a soft nap or hairiness which has escaped all tension
and consequently, such fibres presenting to the eye their points only, have no
apparent brilliancy, but are dull and woolly. Hitherto only woven fabrics or
threads which are finished ready for weaving have been mercerized.
The method which forms the subject of the present application for a patent
consists in mercerizing the cotton during the spinning operation, i.c., mercerizing
the spinning material itself before it is made into a thread. When this result
is obtained these materials can be employed as usual to make, by doubling and
drawing, threads of all sizes.
We treat the cotton, preferably, when in the state of roves as it leaves the presser-
frame, but we can also treat it at any other stage of the spinning operation
particularly when in slivers leaving the card or drawing frame.
The following is our modus operandi:-
The cotton rove or sliver (whatever may be its state when we take it) is
subjected to a certain torsion so as to form a twisted cord or strand sufficiently
strong to withstand the tension required for mercerization.
The cotton cord or strand thus made is mercerized by the known processes to
give it the sheen or lustrous silky appearance; it is then washed, acidulated,
rinsed and dried. When quite dry it is untwisted and restored to the state of
spinning material, that is to say, to a condition fit for drawing. After this it is
subjected to the final spinning operations according to the stage at which it was
interrupted.
These operations usually consist of doubling and drawing. After mercerization
and before beginning to spin again the cotton can be bleached. or dyed in any
shade by known processes.

page_text: With mercerized cotton thus brought to a state fit for drawing we can make
threads of all thicknesses, single or twisted, utilized in weaving. Our process
consequently makes it possible to easily obtain tissues or fabrics of single mercerized
threads.
In reality our invention consists essentially in interrupting, either at the presser-
frame, or the cards or drawing frame, for a certain time the operation of spinning
the cotton threads, and when they are yet in a state fit for drawing they are
rolled into cords of sufficient strength to withstand the necessary tension for
mercerization; then after treating them with the chemical agents while under the
requisite tensile strain, they are untwisted and restored to the state in which they
were when the spinning was interrupted.
In short, we desire to secure as our exclusive and absolute property that process
of preparing cotton which consists in taking cotton roves or slivers on their
leaving the presser-frame, cards or drawing frame, twisting them into a cord and
mercerizing them under tension the said cords being untwisted, when dry, to
restore these roves or slivers to their primitive condition and enable the final
spinning operation to be performed.
Dated this 7th day of December 1898.
PHILLIPS & LEIGH,
Agents for the Applicants.
A New Method of Treating Cotton to give it the Glossy Appearance
of Silk.
We, FERNAND GROS and PAUL BOURCART, of Remiremont, Vosges, in the French
Republic, Spinners, do hereby declare the nature of this invention and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement:-
The present invention relates to a new method of treating cotton to give it the
glossy appearance of silk; and the object of it is to enable yarn or the unspun
fibrous spinning material to be successfully "mercerized."
It may be well before proceeding with the description of our invention to
explain that "mercerizing" is a term now generally used to designate the series of
operations having for their object to impart to cotton a silk-like gloss or sheen.
An important factor in the mercerization of cotton is that the material under
treatment must be stretched quite taut or subjected to considerable tension in
order to counteract the shrinkage that would otherwise take place.
It has been found in practice that the gloss given to cotton by mercerization
becomes more silky in proportion as the chemical solution employed is more
concentrated, and as the ensuing shrinkage is also more considerable in proportion,
the counteracting tension to which the fibre or material must be subjected has to
be increased accordingly. Hence, although excellent results have been obtained
by treating already woven fabrics and finished or spun thread by this said process,
the same can not be said of the unspun fibrous spinning material or yarn in the
form of sliver for example, owing to the fact that the latter having practically
no twist has not the strength necessary to enable it to withstand the tension to
which it would have to be submitted in being treated in a sufficiently concentrated
bath to produce the fine silky appearance desired; besides, the innumerable
free or stray ends of such cotton fibre which project laterally from the exterior
surface thereof and form what is called the "down escape the tension altogether,
and consequently fail to acquire the gloss, in fact they contract and form a sort of

page_text: sheath around the material, which, being dull and woolly in appearance, would
greatly modify even such gloss as might have been imparted to a single fibre
properly finished (mercerized).
The process which accomplishes the object of the present invention consists in
mercerizing the cotton at one of the stages in the preparation of the cotton fibre,
preferably when in the state of roves or construction of the thread preparatory
to the actual spinning operation, in order to obtain mercerized cotton spinning
material which may subsequently be finished as ordinary spinning material accord-
ing to the stage at which the preparation was arrested and the mercerization
begun, or, on the other hand, it may be restored to any of its more primitive
states or even converted into cotton wool.
.
For example, supposing the preparation of the spinning material is arrested
on the completion of the "drawing" operation, then, after the mercerization
the sliver may be subjected to "slubbing" either once or twice, "roving" and
'spinning" and "doubling," to produce a thread of any thickness or size desired.
What characterises cotton when in the condition known in spinning as
<< pre-
pared" cotton, say, in slivers as produced by carding or combing machines, or
in slubs or rovings produced by drawing frames, is that the fibres are assembled
together with little or no twisting, so that each fibre is apt to vary its position
relatively to that of the others by a sliding or slipping motion. In this state
the "prepared" cotton will break asunder at the slightest pull. The individual
fibres, too, are comparatively short, and to subject them to the silkening process
in this condition, it would be necessary to stretch each of them singly, as it were,
and for very small lengths, and that without breaking the continuity of the strand
or sliver and it does not seem practicable to attain this result except perhaps
by very special, and exceedingly complicated machinery which is undesirable for
obvious reasons.
Now, to remedy this defect we propose to bring the cotton temporarily into a
certain transitory condition by two operations, which, at this stage of the spinning
process, would at first sight appear to be quite uncalled for, and it would be so were
it not for the specific object which they enable us to accomplish.
We proceed as follows:-
The cotton in the form of either a carding, drawing. slubbing, or roving sliver,
whichever the stage at which it is taken in hand, is twisted only just as much
as is necessary to impart to the "cord" thus produced, as much strength as it
requires to be capable of withstanding the tension, which shrinking tendency,
owing to its immersion into the concentrated baths, renders imperative. As will
be remembered, concentrated baths alone give the material the desired degree
of silky gloss or sheen. In this preparatory twisting process the conditions of
elasticity and the other qualities which cotton yarn is generally required to
combine, may be disregarded, and it is for this reason that we have selected the
above term "cord" to designate the special and transitory state in which the
cotton is at the time; being in the state of more or less incomplete yarn,
wherein the cotton, while not possessing simply the properties of the prepared
material or sliver yet has acquired and only needs a part of those of yarn or thread.
The amount of temporary twist given to the material will differ according to the
amount of concentration of the mercerizing bath which in turn will depend upon
the degree of gloss desired to be imparted to the material.
"
The cord thus produced is then mercerized by any well-known process,
whereupon it is washed, acidulated, rinsed, and lastly dried; also, either before
or after drying it may be bleached or dyed.
After having thus submitted the cotton; cord to all the necessary operations, we
bring the fibre into a condition in which it shall be capable of undergoing the
whole or part of the spinning processes.
To this end we now untwist it to any extent that may be desirable; in fact,
entirely if required. The mercerized cotton, which may have also been previously
bleached or dyed,-is now restored to the condition of "prepared" cotton, in which

page_text: the fibres are parallel and held together by more or less slight twisting, so that it
can undergo the subsequent spinning operations required to convert it into yarn
or thread or any given thickness.
Or, by simply loosening ("devilling") the cotton it might be restored to the
condition of cotton wool and subjected to all stages of the spinning process from
beginning to end.
66
It will be understood that cotton yarn or thread thus obtained possesses a fine
silky gloss, for two reasons, viz.: (1) because in the condition of cord" the
assemblage of cotton fibre offers as much resistance as is necessary to enable it to
withstand the stretching strain it undergoes in the concentrated baths, which
alone, as above stated, are capable of producing the desired high degree of sheen;
and (2) because the "down" which exists round the "cord," and which escapes the
stretching, and also therefore the mercerizing reaction, is, during the subsequent
spinning operations, closely mixed with the fibre that has acquired the silky
appearance.
In reality, then, our invention mainly consists in temporarily interrupting the
spinning operations, be it at the stage of treatment in the spindle-frame, or in the
carding, combing, drawing, slubbing, or roving machine, and at this stage, we con-
vert the "prepared" cotton, by twisting it as much as may be necessary, into
cords" of sufficient strength to permit them to bear the required tension during
the mercerizing, and after this treatment we obliterate the whole or part of the
twisted effect thus produced by restoring the material either to its initial state
of cotton wool, or to a state approaching that in which it was when the spinning
process was interrupted.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that what
we claim is
The process for imparting to cotton the glossy appearance of silk, characterized
by first twisting the unspun material when in the state of a sliver into a
"cord" of
just sufficient strength to withstand mercerization, then stretching such cord taut,
then submitting it to the mercerization process, after which the cord is untwisted
or restored to the state in which it was prior to such treatment.
Dated the 10th low of Moxa 1800
PHILLIPS & LEIGH,
No. 22, Southampton Buildings, Chancery Lane, London, W.C.,
Agents for the Applicants.