A NEW MANU- FACTURE OF COLOURING MATTER FOR REPLACING LOKAS OR CHINESE GREEN
Year: 1859

page_text: LETTERS PATENT to William Armand Gilbee, of No. 4, South Street,
Finsbury, London, Patent Agent, for the Invention of "A NEW MANU-
FACTURE OF COLOURING MATTER FOR REPLACING LOKAS OR CHINESE GREEN."
-A communication from abroad by Felix Charvin, of Lyons, in the
Empire of France.
Sealed the 1st June 1860, and dated the 28th December 1859.
PROVISIONAL SPECIFICATION left by the said William Armand Gilbee
at the Office of the Commissioners of Patents, with his Petition, on the
28th December 1859.
I, WILLIAM ARMAND GILBEE, of No. 4, South Street, Finsbury, London,
Patent Agent, do hereby declare the nature of the sd Invention of "A
NEW MANUFACTURE OF COLOURING MATTER FOR REPLACING LOKAS OR CHINESE
GREEN," (communicated to me from abroad by Felix Charvin, of Lyons, in the
Empire of France,) to be as follows:-
The Invention communicated to me consists in the employment of and.
mode of treating the bark of the Rhamnus catharticus (or Nerprun purgatif)
for the manufacture of a blue green colour, applicable for dyeing, &c., and.
having the necessary properties for replacing lokas or Chinese green. Tho
process is as follows:-The bark having been rapidly removed from the
branches of the Rhamnus catharticus (by preference from those which are old,
and the bark of which is of the deepest red colour), is then thrown into water

page_text: previously boiled in the proportion of 25 grammes (16 pennyweights troy) of
bark to 1 litre, about 1 pints of water; the liquid is then boiled during about
a quarter of an hour, and the whole is poured into a vessel, which is afterwards
covered over. The bark is left to digest during 1 or 2 nights, according to
the temperature, and at the expiration of this time it is removed, and about a
quarter of a tumbler full of lime water per litre is added to the liquor. The
liquor should then be poured into plates or dishes, and exposed in thin sheets
to the air and light in clear and cold weather to oxidize. it, and in about 6
hours it assumes a blue green colour. The liquor in each plate is then
successively poured into a porcelain saucer, which is placed over a vessel
containing boiling water, and the coloring matter is dried over a sand
bath.
To obtain the colour in a pure state it may be precipitated by potass being
first dissolved in water, and afterwards decanted and filtered.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Armand Gilbee in the Great Seal Patent Office
on the 27th June 1860.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
ARMAND GILBEE, of No. 4, South Street, Finsbury, London, Patent Agent,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-eighth day of December, in the year of our
Lord One thousand eight hundred and fifty-nine, in the twenty-third year
of Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said William Armand Gilbee, Her special licence that I, the said
William Armand Gilbee, my executors, administrators, and assigns, or such
others as I, the said William Armand Gilbee, my executors, administrators,
and assigns, should at any time agree with, and no others, from time to time
and at all times thereafter during the term therein expressed, should and
lawfully might make, use, exercise, and vend, within the United Kingdom of
Great Britain and Ireland, the Channel Islands, and Isle of Man, an Invention
of "A NEW MANUFACTURE OF COLOURING MATTER FOR REPLACING LOKAS OR CHINESE.
GREEN," communicated to me from abroad by Felix Charvin, of Lyons,
in the Empire of France, upon the condition (amongst others) that I,
the said William Armand Gilbee, my executors or administrators, by an
instrument in writing under my, or their, or one of their hands and

page_text: seals, should particularly describe and ascertain the nature of the said
Invention, 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 William Armand Gilbee, 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 thereof, that is to say:-
The Invention communicated to me consists in the employment of the bark
and branches of the Rhamnus catharticus (or Nerprun purgatif) for the
manufacture of a blue green colouring matter, applicable to and having tho
necessary properties for replacing lokas or Chinese green, for dyeing and
printing stuffs, and other colouring purposes, and in the mode or process for
extracting and manufacturing the same.
A substance called lokas is manufactured in China, which is employed for
dyeing stuffs, and other purposes; but the expense of its transport and importa-
tion to other countries considerably increases its price. After many researches
a tinctorial substance has been discovered identical with Chinese lokas, the
cost price of which is lower, and which, like it, yields a blue green colour,
suitable for dyeing all kinds of fabrics, printing stuffs, colouring paper, and
other purposes; which new tinctorial substance is extracted from the plant
called the Rhamnus catharticus (Nerprun purgatif in French).
The process for obtaining the colour consists in throwing into boiling water
the bark of the Rhamnus catharticus or Nerprun purgatif; the oldest and
reddest branches may be employed, and in this case are boiled for five minutes
in the proportion of (twenty-five grammes) sixteen pennyweights troy, of bark,
to (one litre) about one and three-quarter pints of water, and the whole allowed
to digest for a night or two, according to the temperature. It is, however;
better to take the bark indifferently, and to employ even the small branches in
preference, which are crushed and put in boiling water, so as to be covered
thereby. After boiling five minutes, the whole, as in the former case, is turned
into a vessel which is covered over hermetically, and a few hours afterwards,
when the liquor is completely cooled, the bark is separated and washed in
clear water. The water proceeding from this washing is thrown into the first
decoction, to which lime water is added in the proportion of one-twelfth.
Directly after this mixture is effected, the liquor is exposed to the air and light,
by placing it in thin sheets in dishes or plates made of earthenware, zinc, or
other metals. If made of metals whose oxides may colour the liquid, they
must be tiuned. The liquor, which was before of a red colour, becomes blue

page_text: green, and when this change is completed it may be poured into a vessel and
evaporated over a water bath; this residue is subsequently refined by potash ;
it is however preferable to pour the liquor forthwith into vessels to be precipi-
tated by the addition of a sufficient quantity of carbonate of potash; in a little
time afterwards a blue green precipitate forms, which is placed on absorbent
paper spread over ashes or cinders. The liquid part is absorbed by degrees,
the solid part remaining on the paper. This product in drying becomes
detached in thin sheets, similar in colour and form to the lokas imported from
China; other substances, such as caustic potash, salts containing potash, and
alkalies in general, produce the precipitate; but they do not answer so well,
and the result is not so satisfactory. By refining the carbonate of potash before
it is used, the colouring matter can be obtained in a pure state and in crystals,
and it will dissolve entirely in water. In applying this colour to dyeing silk,
woollen, and cotton fabrics, the acetate of alumina is the most efficient mordant,
and by its employment the blue green colour is preserved.
Having now described the nature of the said Invention communicated to me,
and the manner of performing the same, I would have it understood that I do
not confine myself to the precise details herein-before laid down; what I claim
as the Invention communicated to me, and intended to be protected by the
herein in part recited Letters Patent, is,―
First, the employment of the bark and branches of the Rhamnus catharticus
(Nerprun purgatif) and plants of the same family, capable of yielding colour-
ing matter for the manufacture of a blue green colour, similar to and as a
cheap substitute for that obtained from Chinese lokas, for dyeing and printing
stuffs, and other useful purposes, as herein-before described.
Secondly, the process for the extraction and manufacture of the said colour-
ing matter, or substitute for Chinese lokas, in which lime is employed for
fixing the colouring principle, and carbonate of potash for obtaining the
precipitate, as herein-before described.
In witness whereof, I, the said William Armand Gilbee, have hereto set
my hand and seal, this Twenty-seventh day of June, in the year of
our Lord One thousand eight hundred and sixty.
W. A. GILBEE. (L.S.)