IMPROVEMENTS IN BLEACHING FABRICS, YARNS, FIBRES, PAPER PULP, AND OTHER ARTICLES
Year: 1875

page_text: LETTERS PATENT to Frank Wirth, of the Firm of Wirth and Company,
Patent Agency, of Frankfort-on-the-Main, in the Empire of
Germany, for the Invention of "IMPROVEMENTS IN BLEACHING FABRICS,
YARNS, FIBRES, PAPER PULP, AND OTHER ARTICLES."-A communication
from Vincenz Van Baerle, Manufacturer, residing at Worms, in the
Empire of Germany.

page_text: first in a cold solution of silicate of soda, showing 1° Baume. In this
solution it is to remain for three days, but if a solution of 5° Baume is
taken, or even if more, which can be done without hurting its fibre, a
steeping of 24 hours suffices.
After the operation the stuff is pressed out; the liquid, however, can
be used for a second operation if a small quantity of soluble glass is
added to it. The material is then worked with cold water and placed in
a weak solution of chloride of lime or bleaching powder. It will be seen
that the thus heated material bleaches much quicker and is rendered morc
beautiful without that the fibre is attacked as much as with the
hitherto known, such as by boiling in soda, caustic lyc, lime, and final
treating with hyperchlorite of limc.
processes
In order to prepare cellulose from wood, straw, or other vegetable fibre,
it is sufficient to treat the matter in the same way as linen, jute, and the
like; however, it should be first finely divided, and after having been
steeped and washed well in cold water it is boiled in a weak solution of
Baume, or better still, in a rotating rag engine and under weak
pressure. The time required is from 1 to 2 hours. The brown lye is
allowed to flow off, fresh water of 32° C. (at least) is added, the engine
is set in motion, and this operation is repeated as often until the liquid
flows off colorless.
In case one presess to heat the material after the washing in warm
water in a washing engine or in a fulling mill and cold, the previous
operation would remain the same.
After this operation the stuff is bleached in weak hyperchlorite of
lime. The most beautiful white cellulose will then be obtained, which
only requires a steeping in cold water in order to free it entirely from
the chlorine. This method is not only cheaper than the caustic soda
process, but it also yields a whiter fibre and is less dangerous, which
cannot be said of the soda process, where a pressure of fifteen atmo-
spheres is required.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Frank Wirth in the Great Seal Patent Office on
the 9th September 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, FRANK
WIRTI, of the Firm of Wirth and Company, Patent Agency, of
Frankfort-on-the-Main, in the Empire of Germany, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fifteenth day of April, in the year of
our Lord One thousand eight hundred and seventy-five, in the thirty-
eighth year of Her reign, did for Herself, Her heirs and successors,
give and grant unto me, the said Frank Wirth, Her special licence
that I, the said Frank Wirth, my executors, administrators, and assigns,
or such others as I, the said Frank Wirth, my executors, admini-
strators, and assigns, should at any time agreo with, and no others,
from time to time and at all times thereafter during the term therein
expressed, should and lawfully might make, use, excrcise, and vend,
within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN BLEACHING
FABRICS, YARNS, FIBRES, PAPER PULP, AND OTHER ARTICLES,” a communication
from Vincenz Van Baerle, Manufacturer, a person resident at Worms, in
the Empire of Germany, upon the condition (amongst others) that I,
the said Frank Wirth, my executors or administrators, by an instru-
ment in writing under my, or their, or one of their hands and seals,
should particularly describe and ascertain the nature of the said Inven-
tion, and in what manner the same was to be performed, and cause
the same to be filed in the Great Seal Patent Office within six
calendar months next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said Frank Wirth, do hereby declare
the nature of the said Invention, and in what manner the same is
to be performed, to be particularly described and ascertained in and
by the following statement :—
In order to bleach flax, hemp, jute, cotton, or fibre, yarn, cloth, or in
the crude state, according to my system, I lay the article to be bleached
first in a cold solution of silicate of soda showing 1° Baume. In this
solution it is to remain for three days, but if a solution of 5° Baume is
taken, or even if more, which can be done without hurting the fibre, a
steeping of 24 hours suffices,

page_text: After this operation the stuff is pressed out; the liquid, however, can
be used for a second operation if a small quantity of soluble glass is
added to it; the material is then washed with cold water and placed in
a weak solution of chloride of lime or bleaching powder. It will be seen
that the thus treated material bleaches much quicker and is rendered 5
more beautiful without that the fibre is attached as much as with the
processes hitherto known, such as boiling in soda, caustic lye, lime, and
final treating with hyperchloric of lime.
In order to procure cellulose from wood, straw, or other vegetable
fibre, it is sufficient to treat the matter in the same way as linen, jute, 1
and the like. However, it should be first finely divided, and after having
been steeped and washed well in cold water it is boiled in a weak solution
of Baume, or better still, in a rotating rag engine and under weak
pressure. The time required is from 1 to 2 hours. The brown lye is
allowed to flow off, water of 32° C. (at least) is added, the engine 1
is set in motion, and this operation is repeated as often until the liquid
flows off colorless.
In case one prefers to treat the material after the washing in warm
water in a washing engine or in a fulling mill, and cold, the previous
operation would remain the same.
2
After this operation the stuff is bleached in weak hyperchloride of
lime, the most beautiful white cellulose will then be obtained which only
requires a steeping in cold water in order to free it completely from the
chlorine. This method is not only cheaper than the caustic soda process,
but it also yields a whiter fibre and is less dangerous, which cannot be said 2
of the soda process, where a pressure of fifteen atmospheres is required.
In lieu of silicate of soda also silicate of potassium or other alkalies may
be used for my bleaching process, and further, a silicate which is more
alkaline than that mentioned above can be employed, in which case only
a half of this product suffices for giving the same results as above.
In witness whereof, I, the said Frank Wirth, have hereunto set
my hand and seal, this Twenty-third day of August, in the
year of our Lord One thousand eight hundred and seventy-five.
TAT ATZ T.TTATT