IMPROVEMENTS IN THE MANUFACTURE OF STARCH AND OF VEGETABLE SIZING POWDER
Year: 1861

page_text: LETTERS PATENT to Theophilus Redwood, of 19, Montague Street,
Russell Square, in the County of Middlesex, for the Invention of
"IMPROVEMENTS IN THE MANUFACTURE OF STARCH AND OF VEGETABLE SIZING
POWDER."
Sealed the 13th May 1862, and dated the 19th November 1861.
PROVISIONAL SPECIFICATION left by the said Theophilus Redwood at
the Office of the Commissioners of Patents, with his Petition, on the
19th November 1861.
I, THEOPHILUS REDWOOD, of 19, Montague Street, Russell Square, in the
County of Middlesex, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN THE MANUFACTURE OF STARCH AND OF A VEGETABLE SIZING
POWDER," to be as follows:-
This Invention relates, firstly, to the improvement of the process commonly
adopted for the manufacture of starch from rice by the use of a caustic alkaline
solution, and the improvement consists in adding oxide of zinc to the solution
of caustic soda or other alkaline solution in which the rice is macerated.
The effect of thus adding the oxide of zinc is to prevent. fermentation, the for-
mation of mould or fungus, and the generation of acid during the process, and
at the same time to cause the alkaline solution to act more speedily and
effectually upon the hard glutinous portion of the grain so as to set free the
starch. I use the alkaline solution originally described by Mr. Orlando

page_text: Jones in his Patent of the 30th of April, 1840, and I add to every one
hundred gallons of such solution about one pound of oxide of zinc, which is
dissolved in the solution, and in other respects I conduct the process for the
separation of the starch in the same or a similar way to that in which it is
now usually conducted by rice starch makers, excepting that I sometimes use
sulphurous acid and an additional quantity of oxide of zinc in the latter part of
the process, so as to obtain sulphite of zinc mixed with the starch, which
mixture is used with advantage in the manufacture of paper.
My Invention also relates, secondly, to an improved process for the pro-
duction of a vegetable sizing powder, which process consists in adding to
starch an acid solution of chloride of zinc, then drying the starch with the
solution which has been added to it, and, lastly, heating the dried starch in an
oven at a temperature of about 240° Fahrenheit. The starch is thus brought
into a state in which, while it retains its original appearance as to colour it
forms a limpid solution with hot water and this solution is advantageously
used. for sizing paper and for other similar purposes. The acid solution of
chloride of zinc may be made by dissolving twelve pounds of oxide of zinc in
about sixty pounds of commercial muriatic acid, and diluting this with two
hundred gallons of water; the solution so formed will be sufficient for about
one ton of starch.
Having thus described the general nature of my Invention, I may add
that I do not limit myself to the exact quantities or other details herein
given.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Theophilus Redwood in the Great Seal Patent Office on the
16th May 1862.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THEOPHILUS-
REDWOOD, of 19, Montague Street, Russell Square, in the County of Mid-
dlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Nineteenth day of November, in the year of our Lord
One thousand eight hundred and sixty-one, in the twenty-fifth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the said
Theophilus, Redwood, Her special licence that I, the said Theophilus Redwood,
my executors, administrators, and assigns, or such others as I, the said Theophilus
Redwood, my executors, administrators, and assigns, should at any time agree

page_text: 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 MANUFAC
TURE OF STARCH AND OF A VEGETABLE SIZING POWDEE," upon the condition
(amongst others) that I, the said Theophilus Redwood, my executors or
administrators, 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 Theophilus Redwood, do hereby declare
the nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement, that is to say:-
:
This Invention relates, firstly, to the improvement of the process, commonly
adopted for the manufacture of starch from rice by the use of a caustic
alkaline solution, and the improvement consists in adding oxide of zinc to the
solution of caustic soda or other alkaline solution in which the rice is
macerated. The effect of thus adding the oxide of zinc is to prevent fermen-
tation, the formation of mould or fungus, and the generation of acid during
the process, and at the same time to cause the alkaline solution to act more
speedily and effectually upon the hard glutinous portion of the grain, so as to
set free the starch. I use the alkaline solution originally described by Mr.
Orlando Jones in his Patent of the 30th of April, 1840, which solution
contains about two hundred grains of caustic soda in a gallon of water, and I
add to every one hundred gallons of such solution one pound of oxide of zinc,
which is dissolved in it, and this constitutes my "alkaline zinc liquor." The
rice from which starch is to be obtained is put into a tank or cistern lined
with zinc, and having a perforated false bottom, over which a canvas lining
is placed so as to prevent the rice from passing through the perforations in
the false bottom, and sufficient alkaline zinc liquor is added to completely
cover the rice; these are left to macerate for several days, or until the rice
has become soft. If in this process of maceration the liquor becomes much
coloured in consequence of its taking colouring matter from the rice, it may
be run off through a cock at the bottom of the cistern; and a fresh portion_of
the alkaline zinc liquor added, so as again to cover the rice as before: The
maceration may be continued altogether for eight or ten days, the length of
time required depending upon the quality of the rice, as some sorts of rice are

page_text: much harder than others, and require longer maceration. When the rice is found
to be thoroughly softened, so that it can be rubbed into a smooth paste between
the fingers, the liquor is allowed to run off, and the rice is ground or levigated
with water between a pair of horizontal stones, so as to form a fine smooth
fluid of about the consistence of cream. This creamy fluid is mixed with
water in a vat, so that there shall be about five hundred pounds of starch to
one thousand gallons of water; the mixture is then allowed to remain at rest
until the coarser and heavier particles have subsided, and when this has
taken place the finer particles of starch are decanted off with the water while
they remain suspended, and the starch is afterwards allowed to subside in
suitable precipitating vessels or cisterns. This latter part of the process, and
also the subsequent operations of boxing, drying, and racing the starch, are
conducted in the way in which starch makers usually conduct them, if the
product is intended for use as pure starch; but I sometimes vary the process,
as hereafter described, so as to render the product more suitable for certain
special applications, and this I claim as part of my Invention. The creamy
fluid, as it runs from the mill, is diluted with water, and passed through a
strainer, where the finer particles of starch are separated from the coarser
particles; the latter are ground in a mill set for very fine grinding, and
again strained as before, the portion which now refuses to go through the
strainer being finally rejected. The strained liquors from both the first and
second grinding are collected in a large vat furnished with an agitator, and
diluted with water, so that one thousand gallons of the mixture shall contain
about fine hundred pounds of starch. Liquid sulphurous acid formed by
dissolving sulphurous acid gas in water, is now added until one fluid ounce
of the mixture requires two grains of crystallized carbonate of soda to destroy
its acidity and render it neutral. When this amount of acid has been intro-
duced the mixture is agitated for some hours, and then oxide of zinc is added
in the proportion of one pound and a half of the oxide to one hundred gallons
of the mixture. The agitation is continued for about half an hour, and the
mixture is then strained through a fine silk strainer made with number 12
Swiss silk; the strained fluid is collected in cisterns, in which the starch is
allowed to subside. When the precipitate has been deposited, the supernatant
water is decanted off, and the precipitate is put into calico bags, which are
suspended so that the water may drain out, and the bags are afterwards put
into a room heated to about 100° Fahrenheit, where the product is dried:
This product, which contains a portion of sulphite of zinc, is used in the
manufacture of paper. I sometimes add a larger quantity of sulphurous acid
to the starch, so that a fluid ounce of the acidified liquor shall require ten

page_text: grains of carbonate of soda for its neutralization, and then mix with it an
equivalent quantity of oxide of zinc. When thus made, the product, which in
other respects is finished off in the same way as the preceding, is also used in
the manufacture of paper, the sulphite of zinc being a substitute for sulphite.
of soda in such manufacture.
My Invention also relates to the treatment of starch so as to impart pro-
perties to it which increase its value as a material to be used in sizing paper
and for other similar purposes. This part of my process consists in adding to
the starch an acid solution of chloride of zinc, then drying the starch with the
solution which has been added to it, and lastly heating the dried starch in
an oven at a temperature of about 240° Fahrenheit. The acid solution of
chloride of zinc is made by dissolving twelve pounds of oxide of zinc in sixty
pounds of good commercial muriatic acid, and diluting this with two hundred
gallons of water. The solution thus formed is mixed with one ton of starch,
and after allowing the mixture to stand for twenty-four hours the starch is
drained on calico, dried at the common temperature of the air, passed through
a sifting machine to separate the particles of starch from each other, and then
placed in shallow zinc trays in an oven heated by steam to a temperature
ranging from 240° to 250° Fahrenheit. It is exposed to this temperature for
about half an hour, or until it is found that one part of the powder mixed with
four parts of boiling water forms a limpid solution. The starch is now fit for
use as a vegetable sizing powder, which may be advantageously employed for
sizing paper and for other similar purposes.
Having thus explained the general nature of my Invention, and the manner
in which I conduct the process, I may add that I do not limit myself to the
exact quantities or other details herein given.
In witness whereof. I, the said Theophilus Redwood, have hereunto set-
my hand and seal, this Sixteenth day of May, in the year of our
Lord One thousand eight hundred and sixty-two.
T. REDWOOD. (L.S.)