Process of Sizing Paper.
Year: 1890

page_text: Date of Application, 21st July, 1890
Complete Specification Left, 21st May, 1891-Accepted, 27th June, 1891
PROVISIONAL SPECIFICATION.
New Process of Sizing Paper.
I, ALEXANDER MITSCHERLICH, Professor of Chemistry and Doctor of
Philosophy, residing at Friburg, Grand Duchy of Baden, German Empire do
hereby declare the nature of this invention to be as follows:-
Joiner's glue is dissolved by stirring it up several times at a temperature of about
60° C. in a quantity of lye ten times that of the glue during several hours. In
place of joiner's glue other sorts of glue of inferior quality or albuminous sub-
stances may be employed. The value of the same for the process is dependent in
each case on the quantity of the precipitate with the lye. The glue solutions thus
obtained or otherwise produced are added, in stirring up continuously, in thin jets
at ordinary temperature to a quantity of lye equal to fifty times that of the glue,
and the precipitates obtained are allowed to stand during 24 hours with an excess
of lye.
In this precipitating process glue of good quality absorbs about 60% of tannic
acid and about the same quantity of water and 2% of tannic acid are extracted
by this means out of the lye.
This precipitate is mixed with a quantity of water equal to forty times that of
the glue originally employed, to which are added small quantities of chalk or of
other material capable of expelling free acid, preferably carbonate of soda. By
stirring, the precipitate is easily and rapidly dissolved in the said liquids.
This solution is now easily precipitated by adding a very small quantity of acids
such as hydrochloric acid, sulphuric acid, and by adding moreover a quantity of
liquids containing a small quantity of acids such as lye of sulphite cellulose or of
dissolved salts, such as alum and by means of larger quantities of solid bodies, such
as gypsum, chalk, clay, by which means tannic glue is separated in a highly
cementitious and adhesive condition. If this precipitation be effected in the paper
pulp, a paper of great firmness and containing, if desired, a very large quantity of
wood-pulp and earthy matter is produced. In these precipitations an addition of
resin soap, starch and the like in the paper pulp may be employed without any
inconvenience. In this case resin is precipitated usually at the same time with the
tannic glue. The latter increases considerably the imperviousness of the paper to
liquids, while the former produces the great firmness of the same.
"I will now proceed to explain the utilisation of this precipitation in the paper
manufacture by an example.
To the paper pulp which may contain more than 16% of earthy matter, are
added a solution of tannic glue containing a quantity of tannic glue equal to 3%
of the paper pulp, and theu a solution of resin soap with 14% of resin, and the
whole is intimately mixed in the pulp engine.
To this mixture is then added in thin jets and under energetic stirring up of the
mass, a solution containing a quantity of alum equal to 3% of the quantity of paper
pulp; the paper pulp is then worked as usual.
Dated this 21st day of July 1890.
ABEL & IMRAY,
Agents for the Applicant.
COMPLETE SPECIFICATION.
New Process of Sizing Paper.
I, ALEXANDER MITSCHERLICH, Professor of Chemistry and Doctor of
Philosophy, residing at Friburg, Grand Duchy of Baden, German Empire do
hereby declare the nature of this invention and in what manner the same is to be
[Price 4d.1

page_text: performed to be particularly described and ascertained in and by the following
statement :-
Joiner's glue is dissolved by stirring it up several times at a temperature of about
60° C. in a quantity of lye-of sulphite cellulose-ten times that of the glue during
several hours. In place of joiner's glue other sorts of glue of inferior quality or
albuminous substances may be employed. The value of the same for the process
is
dependent in each case on the quantity of the precipitate with the lyc. The glue
solutions thus obtained or otherwise produced are added, in stirring up continuously,
in thin jets at ordinary temperature to a quantity of lye equal to fifty times that of
the glue, and the precipitates obtained are allowed to stand during 24 hours with
an excess of lye.
In this precipitating process glue of good quality absorbs about 60% of tannic
acid and about the same quantity of water and 2% of tannic acid are extracted by
this means out of the lye.
This precipitate is mixed with a quantity of water equal to forty times that of
the glue originally employed, to which are added small quantities of chalk or of
other material capable of expelling free acid, preferably carbonate of soda. By
stirring, the precipitate is easily and rapidly dissolved in the said liquids.
This solution is now easily precipitated by adding a very small quantity of acids
such as hydrochloric acid, sulphuric acid, and by adding moreover a quantity of
liquids containing a small quantity of acids such as lye of sulphite cellulose or of
dissolved salts, such as alum and by means of larger quantities of solid bodies, such
as gypsum, chalk, clay, by which means tannic glue is separated in a highly
cementitious and adhesive condition. If this precipitation be effected in the paper
pulp, a paper of great firmness and containing, if desired, a very large quantity of
wood-pulp and earthy matter is produced. In these precipitations an addition of
resin soap, starch and the like in the paper pulp may be employed without any
inconvenience. In this case resin is precipitated usually at the same time with the
tannic glue. The latter increases considerably the imperviousness of the paper to
liquids, while the former produces the great firmness of the same.
I will now proceed to explain the utilisation of this precipitation in the paper
manufacture by an example.
To the paper pulp which may contain more than 16% of carthy matter, arc
added a solution of tannic glue containing a quantity of tannic glue equal to 3%
of the paper pulp, and then a solution of resin soap with 14% of resin, and the
whole is intimately mixed in the pulp engine.
To this mixture is then added in thin jets and under energetic stirring up of the
mass, a solution containing a quantity of alum equal to 3% of the quantity of
paper pulp; the paper pulp is then worked as usual.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I claim :-
A process of sizing paper materials, consisting in adding solutions of animal glue
or of albuminous substances to the lye of sulphite cellulose, separating the produced
precipitates from the liquid, dissolving the same by means of water free of acid, or
by alkaline water, mixing the solution to the paper pulp and adding small quantities
of acids and liquids containing acids or salts, by which means the tannic glue in
the paper pulp is separated in a highly cementitious condition, substantially as
described.
Dated this 21st day of May 1901
ABEL & IMRAY,
Agents for the Applicant.