IMPROVEMENTS IN THE MANUFACTURE OF PAPER
Year: 1860

page_text: LETTERS PATENT to Thomas Richardson, of Newcastle-upon-Tyne, for the
Invention of "IMPROVEMENTS IN THE MANUFACTURE OF PAPER."
PROVISIONAL SPECIFICATION left by the said Thomas Richardson at the
Office of the Commissioners of Patents, with his Petition, on the 3rd
December 1860.
I, THOMAS RICHARDSON, of Newcastle-upon-Tyne, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN THE MANUFACTURE OF PAPER,"
to be as follows:-
The Invention consists in mixing with the paper pulp (whether the same is
made from rags or other materials, or mixtures of materials) diphosphate of
lime or certain other precipitated compounds of phosphoric acid and lime or
magnesia or other bases either alone or together with sulphites; I obtain
diphosphate of lime for this purpose by treating bones, bone ashes, or other
suitable phosphatic material with sulphurous acid, as described in the Specifi-
cation of certain Letters Patent granted to me, and dated 16th of March 1860,
No. 703. The solution of diphosphate of lime in aqueous solution of sul-
phurous acid is evaporated or heated until the diphosphate of lime precipitates
as a fine white powder, which I employ for mixing with the paper pulp, as
herein-before mentioned. The diphosphate of lime thus prepared contains
more or less of sulphite of lime, which may be allowed to remain in it. Instead

page_text: of evaporating the aforesaid solution of diphosphate of lime in aqueous sul-
phurous acid, I sometimes add to it lime water, or pure hydrate of lime, or the
carbonates of lime, and I then obtain the bone, earth, or triphosphate back
again, more or less mixed with sulphite of lime; I can also substitute in lieu
of lime the alkalies, magnesia, strontia or baryta. In either case I obtain a
fine white precipitated powder, which I employ for mixing with the paper
pulp, as herein-before mentioned. Although I have mentioned the above
process of preparing the above phosphates of lime, &c., any other convenient
process may be employed for that purpose. A fine pearly hardness is thus
communicated to the paper.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Thomas Richardson in the Great Seal Patent Office on the
3rd June 1861.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
RICHARDSON, of Newcastle-upon-Tyne, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Third day of December, in the year of our Lord
One thousand eight hundred and sixty, in the twenty-fourth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Thomas Richardson, Her special licence that I, the said Thomas
Richardson, my executors, administrators, and assigns, or such others as I, the
said Thomas Richardson, my executors, administrators, and assigns; should at
any time agree with, and no others, from time to time and at all times there-
after 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 PAPER," upon the condition (amongst others) that
I, the said Thomas Richardson, 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 Thomas Richardson, do hereby declare the
nature of the said Invention, and in what manner the same is to be per-

page_text: formed, to be particularly described and ascertained in and by the following
statement thereof, that is to say:-
This Invention consists in mixing in the paper pulp (whether the same
is made from rags, or other materials, or mixtures of materials) diphospate of
line, or certain other precipitated compounds of phosphoric acid and lime
or magnesia, or other bases, either alone or together with sulphites; I take the
solution of diphosphate of lime in sulphurous acid obtained by the process as
described in my Patent, dated 16th March 1860, No. 703, or by any other
suitable process, and I either evaporate this solution, or throw in a jet of
steam in any suitable vessel until the diphosphate of lime is precipitated in the
form of a fine white powder. Or instead of applying heat I employ lime
water, or hydrate of lime, or the carbonates of lime, with or without heat, for
the purpose of precipitating the phosphoric acid in combination with the lime,
as bone, earth, or triphosphate of lime, or I employ soda or potash as bydrates
or carbonates, magnesia, strontia, or baryta in the place of lime for the pre-
cipitation of the phospheric acid in combination with one or more bases, as
the case may be. In each case the phosphates of lime so obtained are more
or less mixed with a sulphite of one or more of the other bases, which may be
allowed to remain. The composition of the liquor obtained by acting on the
phosphatic materials with sulphurous acid gas and water, or with aqueous
sulphurous acid varies so much that it is necessary to ascertain by a preliminary
laboratory experiment what quantity of any of the above precipitating agents
is necessary to throw down the whole of the phosphoric acid in a form insoluble
in water. The fine white powders obtained by any of the above processes
is separated by decantation, or otherwise from the liquid and dried by hot air,
steam, or pressure, as is usually practised for this purpose. This white pre-
cipitated powder I mix with paper pulp in the ordinary manner to com-
municate a fine pearly hardness to the paper so manufactured. In those cases
where my process for obtaining the diphosphate of lime is carried out in con-
junction with the manufacture of paper I prefer to mix the sulphurous acid
liquor from the towers or columns with the paper pulp, and then precipitate
the phosphates of lime by any of the plans above described; or I precipitate the
phosphates of lime by any of the plans described in a separate vessel and run the
fine white powder in suspension in the liquid among the paper pulp, thus saving
expense and benefitting by the action of the sulphurous acid or sulphite as an
antichlor. The proportion in which to mix the sulphurous acid liquor with the
paper pulp is determined by the quantity of solid matter in solution, and the
equivalent of the precipitating agent as ascertained by a preliminary experiment

page_text: on a small scale. I do not consider it necessary for my purpose, that when
bones are employed as the source of the phosphates of lime, the gelatine
should be prevented from dissolving in the sulphurous acid liquor. I have
described in the Patent above named, the precautions necessary to be taken to
prevent the gelatine melting and dissolving in the acid liquor, when the object
is to obtain the phosphates of lime distinct from the gelatine. The mixed
solution of gelatine and phosphate of lime may be run directly into the rag
engine instead of the precipitated phosphate of lime, to which any of the pre-
cipitating agents referred to above must be added with the same precautions.
In this case the paper must be air-dried on account of the heat of the drying
cylinders decomposing the gelatine, or the dried water-leaf paper may be carried
through a sizing trough in the usual way, in which is contained a mixture of
gelatine and phosphate of lime, heated to about 90 or 100° Fahrenheit. I find
that the paper thus treated is possessed of a smooth ivory-like surface, and is
much whiter than paper made from rag pulp alone, while its strength is not
in any degree affected. The paper "tub-sized" with the bone gelatine thus
prepared is very hard and impervious to water, and needs the employment of
no alum to cause the size to keep; there is also no liability to decomposition
of the size in the paper which is so often a cause of annoyance, as the small
quantity of sulphurous acid present in the gelatine causes it to keep.
Having now described the nature of my Invention and in what manner the
same is to be performed, what I claim is mixing with paper pulp the phos-
phates of lime, magnesia, strontia, or baryta, in the form of a fine white pre-
cipitated powder, in the manner as herein-before described.
In witness whereof, I, the said Thomas Richardson, have hereunto set my
hand and seal, this Third day of June, in the year of our Lord Oue
thousand eight hundred and sixty-one.
Witness,
CHARLES D. ABEL,
20, Southampton Buildings.
THOMAS RICHARDSON. (L.S.)