IMPROVEMENTS IN THE MANUFACTURE OF PULP
Year: 1860

page_text: LETTERS PATENT to Henry Constantine Jennings, of 8, Great Tower
Street, in the City of London, Practical Chemist, for the Invention of
"IMPROVEMENTS IN THE MANUFACTURE OF PULP."
Sealed the 27th July 1860, and dated the 7th February 1860.
PROVISIONAL SPECIFICATION left by the said Henry Constantine Jennings
at the Office of the Commissioners of Patents, with his Petition, on the
7th February 1860.
I, HENRY CONSTANTINE JENNINGS, of 8, Great Tower Street, in the City of
London, Practical Chemist, do hereby declare the nature of the Invention for
"IMPROVEMENTS IN THE MANUFACTURE OF PULP," to be as follows:-
My Invention is for a process for converting spent tanners' bark, particularly
that kind called twig bark, liquorice root, horse-radish (genus cochlearia), chicory
root, and ligneous substances of various kinds, by subjecting the substances to
the pressure of iron cylinders, so as to divide the larger portions into thin discs
or pieces; these are subjected to the action of a recently made solution of lime
water, as saturated as possible; the whole mass to be raised to a temperature
of about 280° Fahrenheit, by producing within the vessel a tension of from
45 to 60 lbs. pressure upon the inch, after a certain time, to be determined by
experience and the nature of the matter operated upon, I add to the lime water
solution about ten per cent. of soda ashes, or about fifteen per cent. of the
common carbonated soda crystals of commerce, and again raise the tempera-
ture to the above-mentioned degree; after about one hour this solution is

page_text: drawn off and the mass is immersed in a solution of sulphuric, sulphurous, or
hydrochloric acids, to disengage the carbonic acid and neutralise the alkali;
the proportion of these acids should be determined by the quantity of alkali
and organic matter acted upon. After these processes, which in some cases
have to be repeated several times, the organic matter is then bleached by the
action of chlorine, chloride of lime, or other bleaching material, and the organic
matter reduced to pulp by the common pulping machines used by paper
manufacturers and others.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Henry Constantine Jennings, in the Great Seal Patent Office
on the 7th August 1860.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY
CONSTANTINE JENNINGS, of 8, Great Tower Street, in the City of London,
Practical Chemist, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Seventh day of February, in the year of our
Lord One thousand eight hundred and sixty, in the twenty-third year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Henry Constantine Jennings, Her special licence that I, the said
Henry Constantine Jennings, my executors, administrators, and assigns, or such
others as I, the said Henry Constantine Jennings, 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
for "IMPROVEMENTS IN THE MANUFACTURE OF PULP," upon the condition (amongst
others) that I, the said Henry Constantine Jennings, my executors or admi-
nistrators, by an instrument in writing under my or their or one of their
hands and 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 Henry Constantine Jennings, 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 -

page_text: My Invention is for a means or process for converting the spent or used
bark of tanners, especially that kind called branch or twig bark, and also of
liquorice root after the extract or juice is expressed, and of other ligneous or
fibrous organic matters, such as horse-radish, grasses, and plants fit for pro-
ducing paper from their possessing ligneous fibre. I expose these substances
to the action of caustic or quicklime and water, for the purpose of extracting
or removing the gelatine and other animal matter that may have and usually
does combine with tan bark; and also other mucilaginous elements, acids, and
salts that are constituents of other roots and vegetable substances, in combina-
tion with the ligneous fibre. The vessel containing the substances to be operated
upon should be able to resist a pressure of from 45 to 60 lbs. upon the
inch, or on or about four atmospheres' pressure; the quantity of quicklime
will vary according to the nature and quality of the bark; the proportion will
be easily ascertained by practice. The mass will be considerably advanced by
rapid boiling, motion, or the use of any mechanical agent fit for the purpose
of stirring may be employed.
After the bark has been subject to the action of the lime water for about
six hours, the free liquor must be run off and fresh water added so as to cover
the surface of the bark a few inches, then add from 2 to 2 per cent. (accord-
ing to the weight of the organic matter in operation) of soda ashes, as strong
as can be obtained, say, of 55 degrees of alkaline force or strength, or its
equivalent of caustic alkali or caustic potassa. These must be kept at the
ordinary boiling heat of 212° for two or three hours. The colored liquor
must now be withdrawn and the bark distributed on a horizontal pan, having
two circular rollers or cylinders of cast iron, commonly called runners, and used
for grinding solid and hard substances; but the bottom pan must be capable of an
adjustment by screws or levers, or the rollers must be made to rise or descend
by some such means, so as to keep the rollers from having too much contact,
which would reduce the fibre into a powder; while the bark is operated upon
by the rollers and in a damp state, one or two pounds per cent. (in proportion
to the bark) of pearl ashes must be added, taking care to distribute it evenly
and equally over the surface of the bark. When the action of the rollers has
produced an equally soft and even mass of the bark, it must be put into a tank
and permitted to remain one day and night; after this a solution of 2 parts of
sulphuric acid of commerce and 3 parts of hydrochloric or muriatic acid of
commerce, mixed with 50 gallons of water is to be poured over the triturated
bark, and well mixed and incorporated, so as to combine with and neutralize
the alkali that has mixed; these are then to be repeadedly washed with common
water until the mass is perfectly free from either alkaline salts or acids. The

page_text: mass is now to be operated upon by chlorine, hyperchlorous, or chlorine acid,
or enchlorine, or if more convenient, the chlorine or compounds of chlorine
with oxygen may be used in aqueous solution. These are to be washed when
in the beating or pulping machine or engine, with a solution of potassa or
soda, and afterwards finished by the customary bleaching process, prefering,
however, that the use of chlorite or hypochlorite of potash or soda, and
liberating the chlorous acid by weak hydrochloric acid. The whole mass after
being bleached to the degree required for making white paper, white and
brown paper, or brown paper, must be well washed in clear water, as soft as
can be obtained, and then drained until put upon the wires for making paper.
These several processes will require variation, according to the state of the
spent bark, especially in regard to its degree of coarseness and the proportion
of trunk bark to that of twig bark, as the trunk bark contains a larger propor-
tion of red extractive matter, and therefore demands a greater intensity of
manipulation, a longer exposure to chemical action than the lighter kinds of
bark used by tanners. When the residue of liquorice roots are operated upon
the solution of soda may be used instead of potassa and soda ashes, of about
50 degrees of alkaline strength, with four or five times its weight of water
will be the best proportions, and about one pound of soft soap should be mixed
with the ashes and water, and boiled at common pressure for four or five hours,
after which the acids as above should be used, and the bleaching process as
usual.
In witness whereof, I, the said Henry Constantine Jennings, have here-
unto set my hand and seal, this First day of August, in the year of
our Lord One thousand eight hundred and sixty.
H. C. JENNINGS. (L.S.)