An Improved Process of Retting Flax, Hemp, and other Plants.
Year: 1895

page_text: Date of Application, 25th Apr., 1895-Accepted, 6th July, 1895
COMPLETE SPECIFICATION.
An Improved Process of Retting Flax, Hemp, and other Plants.
I, JULIUS HENNIG, of 59 Rue du. Canon, Courtrai, in the Kingdom of Belgium,
Merchant, 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 :—
This invention relates to an improved process of retting flax, hemp and other
textile plants for the purpose of decomposing and separating the glutinous
substances (pectine and the like) by fermentation only, in order to obtain a fibre
which is both soft and strong.
I obtain this result by adding to the retting water a certain quantity of yeast
accompanied or not by an organic acid, and by maintaining the temperature at the
desired degree so as not to interrupt the fermentation.
This process is carried out in the following manner.
I fill the tubs with a quantity of water sufficient to cover the vegetable matter
which is subsequently immersed therein with a layer of liquid extending at least
eight inches in depth. The yeast, first suitably dissolved, is then added, and the
liquid is well stirred, a very feeble solution of an organic acid being added.
If the water has not been previously heated up to about 30° C. (which is
necessary in case of the absence of steam) I proceed to impart the said temperature
to the liquid now and subsequently introduce without delay the vegetable matter to
be treated. Care should be taken to keep the vegetable matter to be treated, fully
in the liquid mixture so that this latter may always cover the said vegetable matter
at least some centimetres.
In carrying out the process I may use 200 grammes of yeast to 1 hectolitre of
water and 10 grammes of citric, tartaric or acetic acid. I wish it understood
however that the quantity of yeast or of acid can be varied according to the nature
of the material under treatment, and according to the quantity of the yeast or of
the water itself and that the acid is to be added only in certain cases.
The process
may be carried out therefore with or without the addition of the acid.
I now maintain the temperature of the surrounding air at a suitable degree in order
not to interrupt the fermenting process which will commence shortly after the
vegetable matter bas been immersed. From the moment when the fermentation
changes from its initial vinous state into the putrescent state, it is necessary to
examine the treated matter, flax, hemp or whatever it may be, several times daily
and to remove the same out of the bath as soon as the fibrous substance freely
detaches from the woody substance. Thereupon the vegetable matter is subjected
to a washing bath, preferably with continuous current. The rest of the operations
is identical with the ordinary retting process.
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. For the retting of flax, hemp and other vegetable textile matter, the use of
yeast with or without the addition of an organic acid added to the retting water
for the purpose of producing a decomposition of the glutinous substances by
fermentation.
2. A process of retting flax, hemp and other vegetable textile inatter consisting
in mixing the retting water with a suitable quantity of yeast, adding or not to the

page_text: said mixture a very small quantity of an organic acid; then immersing in this
liquid mixture the vegetable matter to be retted; maintaining the said liquid
mixture and the surrounding air at a suitable temperature in order not to interrupt
the fermentation; subsequently removing the treated vegetable matter from the
liquid mixture bath after the fermenting process is finished and then subjecting
said vegetable matter to a washing bath of flowing or stationary water.
Dated this 95th day of April 1895.
HASELTINE, LAKE & Co.,
45 Southampton Buildings, London, W.C., Agents for the Applicant.