A New or Improved Solvent or Solvents for Nitrocellulose whereby Improved Solutions are obtained.
Year: 1896

page_text: A New or Improved Solvent or Solvents for Nitrocellulose whereby
Improved Solutions are obtained.
I, ROBERT WILHELM STREHLENERT, of Svedenborgsgatan 2, Stockholm, in
the Kingdom of Sweden, Civil Engineer, do hereby declare the nature of this
invention to be as follows:-
My invention refers to a new or improved solvent or solvents for nitrocellulose,
whereby new or improved solutions are obtained. For this purpose I take
aldehydes, such as formaldehyde, acetaldehyde, paraldehyde, benzaldehyde, with
or without addition of ethylic or methylic alcohol or other suitable diluents, and
I utilize such aldehyde or aldehydes as practical solvents for the various kinds of
nitrocellulose such as proper nitrocellulose, hydronitrocellulose and oxynitrocel-
lulose of which they take up large quantities. Such solutions have a minimum of 1
undissolved matter and are very well adapted for most usages for which solutions
of nitrocellulose are suitable, such as the production of artificial textile filament,
balistic explosives containing nitrocellulose and others. The mode of applying
aforesaid solvents and the approximate proportions thereof in order to render
them available for the purpose of my invention will be fully set forth in my
Complete Specification.
Dated this 10th day of October 1806
BREWER & SON,
London and Leeds, Agents for the Applicant.
COMPLETE SPECIFICATION.
A New or Improved Solvent or Solvents for Nitrocellulose whereby
Improved Solutions are obtained.
L, ROBERT WILHELM STREHLENERT, of Svedenborgsgatan 2, Stockholm, in
the Kingdom of Sweden, Civil Engineer, 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 fabric, artificial silk, which is produced in the well known manner from
cellulose, has not been brought into such general use as had been expected. This
is mainly due to the behaviour of the artificial silk in the presence of water. In
its wet state it loses about 90% of strength, and this property, apart from the
drawbacks occasioned by this fact in the practical utilization of the silk, also
renders the further treatment or working up of the same, especially the dyeing
דנ...

page_text: thereof, considerably more difficult. The means employed heretofore for obviating
this drawback have been found insufficient.
-Now the present invention relates to a process for removing the so-called
hygroscopicity of artificial silk that is to say, its tendency to absorb water. This
process consists in adding to the solvent for the nitrocellulose, formic aldehyde,
acetic aldehyde, paraldehyde, benzaldehyde or other substances belonging to the
same group, or in treating the draw-out thread with a solution of such substances.
The property of formic aldehyde, of forming with gelatine, a compound which
is insoluble in water, has been lately observed and utilized. According to the
present invention this property of formic aldehyde or of its substitutes or equivalents
above referred to, is employed to act upon other substances containing nitrogen,
and in particular upon artificial silk made from nitrocellulose, for the purpose of
increasing the resistance of the material against water, and it has been found that
such an increase can be effected in a high degree. The quantity of formic
aldehyde or of the substances above mentioned which is to be mixed with the
solvent or with the agent required for treating the finished spun thread before
its denitration, may amount to as much as 15% of the weight of the nitro-cellulose.
As formic aldehyde, or the above-mentioned equivalents in combination with
ethyl alcohol or methyl alcohol, ether etc, constitute an extremely effective solvent
for nitrocellulose, it is most advantageous to add and mix the formic aldehyde
or the above mentioned substances at the very commencement of the treatment
of the nitrocellulose.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is:-
The process for the production or artificial silk which shall be proof against the
action of water, consisting in either adding to or mixing with the solvent for the
nitro-cellulose before drawing out the threads, formic aldehyde, acetic aldehyde,
paraldehyde, benzaldehyde, or other substances of the same group, or in treating
the silk after being spun, with one of the above mentioned substances, substantially
as described.