Improvements in the Process of Tanning Hides, Skins, or the like.
Year: 1896

page_text: Date of Application, 28th July, 1896-Accepted, 2nd Jan., 1897
COMPLETE SPECIFICATION.
Improvements in the Process of Tanning Hides, Skins, or
the like.
I, JOHANNES BLUNCK of 46 Nowolipiestrasse, Warsaw, Poland in the Empire
of Russia, Manufacturer, 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 :-
By the process which forms the object of the present invention it is possible to
thoroughly tan skins and fells in a period of from 1 to 8 days in the ordinary
course of tanning without the employment of mechanical movement, that is to say,
without rotary vats.
After the skins and fells have been treated in the ordinary way for the
unhairing, that is to say limed, unhaired and mordanted by the use of common or
rock salt and thus rendered suitable for the reception of the tan liquor, the skins
or fells are placed in a stationary vat, and there subjected to a treatment with
vegetable tanning materials, by the direct action of which the necessary degree of
tanning is attained.
As suitable tanning materials I employ vegetable liquors made by the use of
salts from extracts of the usual barks, myrabolams, valonia, dividivi, gambier,
quebrachywood and the like, and it suffices to simply suspend the hides or fells in
the tanning vats containing such liquors, after which, without the necessity of
mechanically rotating or agitating the said vats, the tanning is completed in such
a short space of time as has never hitherto been attained. The vegetable liquors
may either be made of the said barks, myrabolams, valonia or the like separately,
or of several of these tanning materials combined, and then so much solution of
salt is added to the liquor until the desired number of degrees Beaumé is attained.
As a suitable proportion, I employ for instance 100 litres of water to which is
added 25 kilos. of extract of oak bark, myrabolams, valonia, dividivi or
quebrachywood so that the aerometer indicates 4° Beaumé. If 10 kilos. of dissolved
salt be then added thereto a tan liquor of 8° Beaumé results, and the hides or fells
are suspended in this and tanned in a very short space of time as already stated
without mechanical movement or agitation of the vats.
According to the quantity of salt solution added to the liquor, the strength of
the latter may be regulated according to requirements, and the duration of the
tanning may thereby be shortened at will.
As will be seen without any further explanation, this improved process is
entirely independent of any movement of the tanning vats by mechanical power
or hand, and may therefore be employed with equally good results even in the
smallest of tanneries.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. A rapid tanning process, consisting in adding salt solution to a liquor formed
of extracts of bark, myrabolams, valonia, dividivi, gambier, quebrachywood or
the like, until the liquor indicates the desired number of degrees Beaumé, the
hides or fells, which have been limed and unbaired and mordanted in the ordinary

page_text: manner and thereby rendered more receptive, being then suspended in stationary
vats filled with the said liquor, and thoroughly tanned within 1 to eight days
without any mechanical movement.
Dated this 27th day of July 1896.
WM. P. THOMPSON & Co.,
Of 6 Lord Street, Liverpool, Agents. for the Applicant.