AN IMPROVED PROCESS OF TREATING VEGETABLE FIBRES TO IMPART TO THEM A SILKY APPEARANCE
Year: 1876

page_text: LETTERS PATENT to Paul Magner, of Percy Street, in the County of Middlesex,
Analytical Chemist, for the Invention of "AN IMPROVED PROCESS OF TREATING
VEGETABLE FIBRES TO IMPART TO THEM A SILKY APPEARANCE."
Sealed the 21st December 1876, and dated the 12th October 1876.
PROVISIONAL SPECIFICATION left by the said Paul Magner at the Office
of the Commissioners of Patents on the 12th October 1876.
PAUL MAGNER, of Percy Street, in the County of Middlesex, Analytical Chemist.
"AN IMPROVED PROCESS OF TREATING VEGETABLE FIBRES TO IMPART TO THEM A
SILKY APPEARANCE."
My Invention relates to a process for treating vegetable fibres, such as cotton,
flax, hemp, China grass, jute, and the like, to give them a glossy or lustrous
appearance, so that they may be used as a substitute for silk, and when manufactured
into fabrics will be greatly superior with regard to strength and substance to such
fibres in their natural or ordinary condition.
My improved process is as follows, that is to say, the cotton, linen, or other
vegetable fibre is first freed from starchy, and fatty, and extractive matters, and
other impurities, by any suitable means, and is converted into binitrated cellulose.
For obtaining this product the best method is to employ a mixture of seven volumes
of sulphuric acid of a density of 66° Baumé, and three volumes of azotic acid of a
density of 1420. The cellulose is immersed in this mixture cold for from twelve to
fifteen minutes, and the mass is kept in constant agitation so that all parts may be
perfectly impregnated with the acid liquor. Then while still moist the binitrated
cellulose, which is quite neutral to test paper, is treated with a reducing agent or
the like, such as peroxide of hydrogen, bisulphide of hydrogen, chlorine in a nascent
state, or by any chemical agent which will give the hydrogen or a portion of the
hydrogen that it contains to one or more equivalents of oxygen of the binitrated
cellulose to form water. The textile material is then washed and rinsed in boiling
water, then in cold water, and steeped for a few minutes in an acetic or ammoniacal
solution of silk or feathers in the following proportions:-One part of solution of
[Price 2dl

page_text: silk or two parts of solution of feathers for each one hundred parts of vegetable
fibres.
For making this solution I proceed as follows:-I introduce 100 parts of acetic
acid of a density of 1044 into a digester or other suitable apparatus capable of
sustaining a pressure of eighteen atmospheres, then I add two parts of silk or three
parts of feathers, and heat the apparatus till the interior temperature is raised to
about 250° centigrade. I maintain the pressure and temperature for about two
hours and then allow the apparatus to cool. The solution is then perfectly clear
and ready for use.
The binitrated cellulose after its immersion in the above described solution is
placed in an apparatus or vessel wherein a partial vacuum may be produced. (The
ordinary extract vacuum pan will be found convenient and suitable for this purpose.)
I maintain in the said apparatus or vessel a moderate temperature, say from 60° to
65° centigrade, to dry the fibres gradually. The vacuum or partial vacuum is
necessary to free the said fibres after their treatment by my process from the acetic
acid or the ammonia which has been employed in the above process and which
passes off in the form of gas.