Process of Modifying the Properties of Fibres used in the Manufacture of Paper.
Year: 1890

page_text: Date of Application, 2nd Apr., 1890
Complete Specification Left, 5th May, 1890-Accepted, 19th July, 1890
PROVISIONAL SPECIFICATION.
Process of Modifying the Properties of Fibres used in the
Manufacture of Paper.
1, CARL KELLNER, of Bartensteingasse 8, Vienna 1, in the Austrian Empire,
Chemist, do hereby declare the nature of this invention to be as follows:-
As is well known, particular properties are imparted to paper according to the
nature of the materials used in its manufacture. The most prominent differences are
observed between papers made of pure linen fibre on the one hand, and papers in the
manufacture of which pure cotton fibre has been used, on the other hand. The former
are hard to the touch, crack on being folded and are more or less translucent and like
parchment, while the latter are distinguished by a soft velvety touch, can be crumpled
without cracking and are somewhat opaque even when thin. This may be strikingly
demonstrated by comparing the paper on which the bank notes of the Bank of
England are printed with blotting paper. All kinds of paper lying between these two
examples, which shew the greatest differences, can be made by mixing together
fibres which bave the properties of linen fibres and fibres of a cotton-like description.
Hitherto, it has been generally assumed that the particular nature of the paper
depends on the shape of the fibre, which can be easily observed under the
microscope.
I have found, however, that besides the shape of the fibres, which no doubt exerts a
certain influence upon the properties of the paper, there is another and essential
circumstance viz., the chemical composition of the matter making up the cellular tissue
of the fibres.
In order to establish the truth of this assertion I may point to the fact that ordinary
cotton and gun cotton shew no difference under the microscope, although, as is well
known, cotton undergoes a thorough alteration when being nitrated; it becomes
insoluble in acids, but soluble in a mixture of ether and alcohol, etc.
"Owing thereto, paper made of gun cotton presents properties, which differ greatly
from those of paper made of ordinary cotton fibre; the nature of the former is akin to
that of linen fibre paper.
Now this invention consists in a process by which the properties of the fibres
usually employed for making paper can be altered at pleasure; the said process even
enables me to impart to linen-like fibrous materials the properties of cotton fibres, and
to cotton-like materials a character resembling that of linen fibres.
This is achieved by treating cotton-like fibrous materials with a weak acid, and
linen-like fibres with a weak alkali.
It is obvious that this process can be carried into practice in numerous different
ways; I have found, however, that the following methods give good results in
practice:
When paper having similar qualities to that made of linen fibres is to be made of
cotton-like fibres, the fibrous material is, in the state of half-stuff and in an ordinary
boiler, boiled with a solution of a weak acid. I have found that solutions of acid
sulphates (hydrosulphates) and solutions of weak organic acids in caustic soda (sodium
salts of such acids) answer especially well.
For modifying the nature of cotton fibres I make use of a solution of sulphate of
alumina or of hydrosulphate of soda or potash, containing from 15 to 7 ounces per
gallon, and for imparting a linen-like character to jute, esparto an similar fibres,
a solution of abietate or sylvate of soda, containing from 0-7 to 7
gallon.
ounces per
Cotton fibres are to be boiled about 2 hours under a pressure reaching three
atmospheres, and the other fibrous materials referred to from 3 to 5 hours under a
pressure reaching 14 atmospheres.

page_text: After the boiling the half-stuff is freed from the liquid contained therein by
methodically lixiviating it with water, which may be used in a warm state, and with
the aid of lixiviating apparatus, which may be with advantage arranged like Shank's
lixiviating tanks in soda works. The object of this lixiviation is to recover the liquid
in the least possible altered state, in order to admit of mixtures of the liquids run off
from the lixiviating tanks being re-used for boiling other fibrous material.
The half-stuff taken out from the lixiviating tanks may be worked into paper in the
usual way.
When it is desired to made of linen-like fibrous material paper having the properties
of that made of cotton fibre, the said fibrous material is boiled, in the state of half-
stuff, in a solution of an alkali, such as soda-ash, caustic soda, water-glass, borax,
potash, etc. Boiling may be effected in closed vessels, under a pressure up to
3 atmospheres, or in open boilers during from 2 to 8 hours. Afterwards the
material is lixiviated, washed and worked.
To linen-like fibrous materials the character of cotton may also be imparted by
piling them up in a wet state and allowing them to remain in this condition until they
become warm spontaneously.
The chemicals required for transforming the fibres may also be obtained by the
electrolysis of suitable compounds, the solutions of which surround the fibres under
treatment. In this case, the more thorough effect produced by the chemicals in the
nascent state, enables the boiling process to be dispensed with. When carrying out
this process, the fibrous material is impregnated with a solution of nitrates, acetates
or sulphates or with diluted nitric, acetic or sulphuric acid, and afterwards it is passed
between two cylinders, which are connected with the two poles of an electric current
generator.
When the process is carried out in this way, it is advisable to pass the material
between the cylinders on a felt apron, and to so connect the cylinders with the poles
of the electric generator that the lower cylinder is made the electrode on which gather
the ions not intended to act on the fibrous material.
In the case of Jinen-like fibre which is to have imparted to it the properties of
cotton, the lower cylinder must be made the anode and the upper one the cathode, in
order to cause the fibre to be acted upon by the alkalies and hydrogen in the nascent
state, immediately on being set free, or the alkalies and the hydrogen formed by
secondary recombinations in and between the fibres.
On the other hand, for so transforming cotton-like fibres as to give them the
character of linen fibre, the same are to be brought in contact with the acids and the
oxygen set free, and this is effected by making the lower cylinder the cathode and
the upper one the anode.
Dated this and dow of Anvil 1000
COMPLETE SPECIFICATION.
Process of Modifying the Properties of Fibres used in the
Manufacture of Paper.
I, CARL KELLNER of Bartensteingasse 8 Vienna 1, in the Austrian Empire,
Chemist, do hereby declare the nature of this invention and in what manner the
same is to be performed to be particularly described and ascertained in and by the
following statement :-
As is well known particular properties are imparted_to_paper_according_to_the_
nature of the materials used in its manufacture. The most prominent differences are
observed between papers made of pure linen fibre on the one hand, and papers in the
manufacture of which pure cotton fibre has been used, on the other hand. The former
are hard to the touch, crack on being folded and are more or les translucent and like
parchment, while the latter are distinguished by a soft velvety touch, can be crumpled
without cracking and are somewhat opaque even when thin. This may be strikingly

page_text: demonstrated by comparing the paper on which the bank notes of the Bank of England
are printed with blotting paper. All kinds of paper lying between these two examples
which show the greatest differences can be made by mixing together fibres which
have the properties of linen fibres, and fibres of a cotton like description.
Hitherto, it has been generally assumed that the particular nature of the paper
depends on the shape of the fibre, which can be easily observed under the
microscope.
I have found, however, that beside the shape of the fibres, which no doubt exorts a
certain influence upon the properties of the paper, there is another and essential
circumstance riz., the chemical composition of the matter making up the cellular
tissue of the fibres.
In order to establish the truth of this assertion I may point to the fact that ordinary
cotton and gun cotton show no difference under the microscope, although, as is well
known, cotton undergoes a thorough alteration.when being nitrated; it becomes
insoluble in acids, but soluble in a mixture of ether and alcohol &c.
Owing thereto, paper male of gun-cotton presents properties, which differ greatly
from those of paper made of ordinary cotton fibre; the nature of the former is akin to
that of linen fibre paper.
Now, this invention consists in a process, by which the properties of the fibres
usually employed for making paper can be altered at pleasure; the said process even
enables me to impart to linen-like fibrous materials the properties of cotton fibres, and
to cotton-like materials a character resembling that of linen fibres.
This is achieved by treating cotton-like fibrous materials with a weak acid, and
linen-like fibres with a weak alkali.
It is obvious that this process can be carried into practice in numerous different
ways; I have found however, that the following methods give good results in
practice:
When paper having similar qualities to that made of linen fibres is to be made of
cotton-like fibres the fibrous material is, in the state of half-stuff and in an ordinary
boiler, boiled with a solution of a weak acid. I have found that solutions of acid
sulphates (hydrosulphates) and solutions of weak organic acids in caustic soda (sodium
salts of such acids) answer especially well.
For modifying the nature of cotton fibres, I make use of a solution of sulphate of
alumina or of hydrosulphate of soda or potash, containing from 1.5 to 7 ounces
per gallon, and for imparting a linen-like character to jute, esparto and similar
fibres, a solution of abietate or sylvate of soda, containing from 0.7 to 7 ounces per
gallon.
Cotton fibres should be boiled for about 2 hours under a pressure reaching
3 atmospheres, and the other fibrous materials referred to from 3 to 5 hours under a
pressure reaching 1 atmospheres.
After the boiling the half-stuff is freed from the liquid contained therein by
methodically lixiviating it with water, which may be used in a warm state, and with
the aid of lixiviating apparatus,, which may be with advantage, arranged like Shank's
lixiviating tanks in soda-works. The object of this lixiviation is to recover the
liquid in the least possible altered state in order to admit of mixtures of the liquids
run off from the lixiviating tanks being re-used for boiling other fibrous material.
The half-stuff taken out from the lixiviating tanks may be worked into paper in the
usual way.
When it is desired to make of linen-like fibrous material paper having the properties
of that made of cotton fibre, the said fibrous material is boiled, in the state of half-
stuff, in a solution of alkali such as soda-ash, caustic-soda, water-glass, borax,
potash, etc. Boiling may be effected in closed vessels under a pressure up to
34 atmospheres, or in open boilers during from 2 to 8 hours. Afterwards the
material is lixiviated, washed and worked.
To linen-like fibrous materials the character of cotton may also be imparted by
piling them up in a wet state and allowing them to remain in that condition until they
become warm spontaneously.

page_text: The chemicals required for transforming the fibres may also be obtained by the
electrolysis of suitable compounds, the solutions of which surround the fibres under
treatment. In this case the more thorough effect produced by the chemicals in the
nascent state, enables the boiling process to be dispensed with. When carrying out
this process, the fibrous material is impregnated with a solution of nitrates, acetates,
or sulphates, or with diluted nitric, acetic or sulphuric acid, and afterwards it is
passed between two cylinders, which are connected with the two poles of an electric
current generator.
When the process is carried out in this way it is advisable to pass the material
between the cylinders on a felt apron, and to so connect the cylinders with the poles
of the electric generator that the lower cylinder forms the electrode on which gather
the ions not intended to act on the fibrous material.
In the case of linen-like fibre which is to have imparted to it the properties of
cotton, the lower cylinder must be the anode, and the upper one the cathode, in order
to cause the fibre to be acted upon by the alkalies and bydrogen in the nascent state,
immediately on being set free, or the alkalies and the hydrogen formed by secondary
recombinations in and between the fibres.
On the other hand for so transforming cotton-like fibres as to give them the
character of linen fibre, the same are to be brought in contact with the acids and the
oxygen set free, and this is effected, by making the lower cylinder the cathode and
the upper one the anode.
Having now particularly described and ascertained the nature of the said inven-'
tion and in what manner the same is to be performed I declare that what I
claim is :-
1st. The process of modifying the qualities of fibrous materials used in paper
making, this process consisting in treating linen-like fibres with feeble alkalies and
cotton-like fibres with feeble acids.
2nd. In the process referred to in the 1st claim boiling the fibrous material after it
has been reduced to half-stuff, with weak solutions of alkalies or acids respectively as
described.
3rd. In the process referred to in the 1st claim treating cotton-like fibrous material
with sulphate of alumina, hydrosulphate of soda or potash or with abietate or sylvate
of soda, in order to impart to the material the properties of linen fibres.
4th. In the process referred to in the 1st claim treating linen-like fibrous material
with caustic soda, carbonate of soda, or silicate of soda or of potash, in order to impart
to the material the properties of cotton fibres.
5th. In the process referred to in the 1st claim impregnating the fibrous material
with a solution of an acetate, nitrate or sulphate or with diluted acetic, nitric or
sulphuric acid, and afterwards passing it between two cylinders, which are connected
to the poles of an electric current generator.
Dated this 5th day of May 1890.
C. KELLNER.
By L. W. per F. B.