AN IMPROVED METHOD OF TREATING VULCANIZED FIBRE AND LIKE MATERIAL, TO RENDER THE SAME PERMANENTLY FLEXIBLE
Year: 1884

page_text: I, FRANKLIN TAYLOR, a Citizen of the United States, residing in the City of
Wilmington, and State of Delaware, U.S.A., Manufacturer do hereby declare the
nature of my Invention for AN IMPROVED METHOD OF TREATING VULCANIZED
FIBRE AND LIKE MATERIAL, TO RENDER THE SAME PERMANENTLY FLEXIBLE,
and in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement :-
In many of the uses to which vulcanized fibre, gelatinized fibre, leatheroid,'
vegetable fibre which has been treated by the well known sulphuric acid process, and
such like material, are applied, it is desirable that the material should possess more
or less softness or flexibility, and that this quality should be lasting. For instance,
when the material is used for many kinds of packings, washers, etc., more or less
flexibility is required, and of course it is important that the material should not
become dry and hard with age, but should retain its flexibility as long as possible.
I impart this permanent flexibility and softness to the fibre by subjecting it to a
bath of deliquescent salt subsequent to the organic change produced in the vegetable'
fibre during its manufacture.
When vulcanized fibre is manufactured according to the well known Schmidt
method set forth in United States Patent No. 113,454, the vegetable fibre or
cellulose is treated either with mother-water resulting from the manufacture of'
chloride of zinc or other chlorides, or with a solution of chloride of zinc or other
chloride. In either case, however, this active agent for producing the organic
change in the cellulose to convert it into vulcanized fibre is thoroughly washed out
of the fibre; and then the fibre is treated with a bath of water and glycerine or
sugar water to render it flexible.
The United States Patent of Daniel Hanna, No. 120,380, relates to the treatment
of vegetable fibre by chloride of zinc or mother-water of chloride of zinc, and
suggests that when a hard paper is required nearly, if not all, of the solution is
washed out from the paper; but when a soft paper is to be produced comparatively.
little of the solution is washed out. This manner of producing flexible fibre is
objectionable for various reasons, and principally because of the great difficulty
and practical impossibility of producing uniformn results, as it is impossible to
always wash the fibre to the same degree to produce equality of flexibility in the
same batch of material.

page_text: In my improved method the vegetable fibre or cellulose is first treated with the
active agent, whatever it may be, to produce the required organic change is
preferably then thoroughly washed and then subjected to a bath of a solution of
deliquescent salt of a definite and known strength. The deliquescent salt may be
used either alone, or a bath composed of a solution of deliquescent salt and glycerine
or sugar water may be used. While both baths give most excellent results in
practice, I prefer the last named.
The method of treating vegetable fibre for the manufacture of vulcanized fibre,
and such like material, is so well known and fully set forth, both in British and in
United States Patents, that any description here is unnecessary.
In carrying out my Invention I preferably take the fibre as it comes from the
cleansing bath while yet soft and saturated with moisture, and treat it with a bath
of a solution of chloride of zinc, or other deliquescent salt, which bath may be of a
strength of from 15° to 30° Beaumé more or less, according to the degree of
flexibility it is desired to impart. When the deliquescent salt is used in com-
bination with a glycerine or sugar water solution, I preferably take a solution of
either of the latter of from 20° to 30° Beaumé, and add to it from 30 to 60 per
cent. in bulk of the solution of deliquescent salt at a strength of about 30° Beaumé
more or less. As before remarked, these proportions may be changed according to
the amount of softness and flexibility desired.
While I prefer to take the material as it comes from the cleansing bath and
subject it to the softening baths described, I may treat the dried fibre in the same
way. Of course, however, in that case the fibre would have to be immersed in the
solution for a much greater length of time. The wet fibre as it comes from the
bath may be immersed in the softening solution for from six to forty-eight hours,
the length of time depending upon the thickness or size of the mass immersed and
the amount of softness to be imparted to it.
When working according to my improved method, as the strength of the bath
is always definite and ascertained, fibre of uniform flexibility may readily be
manufactured, and the material produced retains its softness for a long period
of time..
As above stated, I prefer to use the deliquescent salt in connection with sugar
or glycerine, as I believe better and more permanent results are obtained thereby.
I have used chloride of zinc as the deliquescent salt employed, though various other
deliquescent chlorides may be used; as, for instance, the chlorides of tin, calcium,
and other chlorides, used in 'the manufacture of vulcanized fibre.
I am aware that heretofore chloride of calcium mixed with a composition for
printers' inking rollers has been suggested as a means of rendering the rollers soft
and flexible.
Approximately equal and good results, at least results much better than those
heretofore attained, may be had in some cases by omitting the cleansing bath and
taking the material directly from the bath of the active agent and immersing it in
a bath of a definite strength of solution of deliquescent salt, or of deliquescent
salt and glycerine or sugar water. With a compound solution of glycerine or sugar
and deliquescent salt good results may be obtained in this way.
Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed, I declare that what
I claim is
1. The method of treating vegetable fibre after it has undergone organic change
and cleansing in the process of manufacturing vulcanized fibre and such like
material, which consists in immersing it in a bath of a solution of deliquescent salt,
as described.
2. The method of treating vulcanized fibre and such like material to impart
softness and flexibility thereto, which consists in taking the fibre after the organic
change therein has been produced in the process of manufacture, and subjecting said
fibre to a bath of a solution of deliquescent salt, as described.

page_text: 3. The method of treating vulcanized fibre and such like material, which consists
in taking the vulcanized fibre after the organic change therein has been produced
in the process of manufacture, and subjecting it to a bath of a solution of deliquescent
salt combined with glycerine or sugar water, as described.
4. The herein described bath for softening vulcanized fibre and such like material,
which consists in the combination of a solution of a deliquescent salt and glycerine
or sugar, as set forth.
5. The method of treating vulcanized fibre and such like material to impart
softness and flexibility thereto, which consists in taking the fibre after the organic
change therein has been produced in the process of manufacture, and subjecting it
to a softening bath of a solution of chloride of zinc, or of a solution of chloride of
zine combined with glycerine or sugar water.
6. The method of treating vulcanized fibre and such like material after it has
undergone the organic change and subsequent cleansing in the process of manu-
facture, which consists in subjecting the material to the action of a bath of a
solution of chloride of zinc, or of chloride of zinc combined with glycerine or sugar
water.
7. The herein-described bath for softening vulcanized fibre and such like material,
which consists in the combination of a solution of chloride of zinc and glycerine or
sugar water.