Improvements in and relating to the Manufacture of Cements for Making Mortars suitable for the Production of Artificial Stone.
Year: 1894

page_text: Date of Application, 10th Nov., 1894
'omplete Specification Left, 12th Mar., 1995-Accepted, 9th Nov.,
1895
PROVISIONAL SPECIFICATION.
Improvements in and relating to the Manufacture of Cements for
Making Mortars suitable for the Production of Artificial Stone.
We, EUGEN WECKWARTH, of 130, Apertado, Lima, in the Republic of Peru,
at present residing at 98 Dresdenerstrasse, Berlin, in the Empire of Germany,
Doctor of Philosophy and Chemist, and MAX HOEFT of 75 Krausenstrasse,
Berlin, aforesaid, Manufacturer, do hereby declare the nature of this invention to
be as follows :-
This invention relates to the manufacture of dry cements suitable for the
It is well
preparation of mortar for use in the production of artificial stone.
known that albuminous substances or proteids, such for example as albumen, casein,
glue, blood, and cheese (hereinafter referred to generally as albuminous substances)
have a very favourable action upon the adhesive property of plaster of Paris and
also of lime, and impart to cement or mortar mixtures of which they form part, a
viscous nature that renders them extremely suitable for use when it is desired to
produce in an easy manner, stucco or plaster work having a smooth surface. Now
an object of this invention is to obviate a drawback generally attending the
This drawback
manufacture of cements or mixtures of the kind referred to.
consists in the fact that the albuminous substances which have always been
employed in a moist or fluid state, offer, on account of their viscous and sometimes
even gluey nature, a considerable resistance to intimate mingling with the plaster
of Paris or lime, or with a mixture of these two substances, so that the distribution
of the albuminous substances in the cement is often very far from uniform. The
consequences of this are that the finished stucco or plaster work has not a uniform
degree of hardness and that its surface has an ununiform appearance, which are,
from a practical point of view, very serious defects.
Now in order to obviate this drawback and to produce mixtures of albuminous
substances with plaster of Paris or lime, or with both, of the greatest possible
uniformity, we proceed as follows:-
We employ the albuminous substances in a dry state: they may be either normally
dry or normally moist or liquid; if the latter, we dry them, the necessary precautions
being taken. These substances are reduced to powder and mixed with ground
burned gypsum, that is to say, plaster of Paris, or with slaked and dried lime that
has been previously reduced to powder, or with a mixture of plaster of Paris and
lime. Or we may mix the dry non-comminuted albuminous substances with the
plaster of Paris or with the slaked and dried lime, or with a mixture of them, and
then reduce the whole te powder in any suitable manner. A third plan is to take
the albuminous substances in a moist or liquid state and mix them intimately with
lime;
then to dry this mixture at a temperature up to about 50° C.; and finally to
reduce the mixture to powder. When required for use the cement thus prepared
may be employed either alone or mixed with plaster of Paris. Whichever of the
hereinbefore described methods be followed, the result will always be a floury dry
mixture or cement which will remain unaltered even though atmospheric air be not
absolutely excluded from it, so that the manufacture therefore can be carried out
rationally and with profit, on a large scale and with the use of machinery, and in
this consists the principal object of our present invention.
When mixed with water or with a dilute solution of potash or soda, these

page_text: floury mixtures or dry cements yield a mortar which is extremely uniform in
composition and is very suitable for the execution of stucco work. Under this
term is to be understood not only the production of such work in its strict sense,
but also the covering of walls, ceilings, floors, external parts of buildings, and the
like, and also the production of castings in moulds.
In some cases it is advisable to add to the dry cement prepared as described, a
salt or salts that will combine with plaster of Paris to form an insoluble or very
slightly soluble compound with the object of increasing the hardness of the stucco
or other work after the cement has set. As suitable salts of this kind special
mention may be made of sulphates and double salts, such as have long been
employed for hardening plaster of Paris. An addition of boric acid, or of a
borate, particularly potassium borate, in small quantities, is also advisable in order
to delay the setting of the cement. These additions may be made in preparing the
plastic cement or mortar from the dry cement, but we recommend rather that
these additions should be made to the dry cement during the manufacture thereof.
In this case the additional substances are to be added to and mixed in a dry
state, and preferably in a finely divided condition, with the mixture of substances
comprising the dry cement.
But these additional substances can also be employed in a moist or liquid
condition, if no plaster of Paris contained in the cement. The moist mixture
thus produced must then be suitably dried and pulverized. Plaster of Paris must
not, for well known reasons, be added to a moist mixture or be present in a dry
mixture to which a paste or liquid is added, if the resulting mixture is to be kept
for future use. If the addition of plaster of Paris is necessary, then the moist
mixture must first be dried.
It will be readily understood that other additions, besides those mentioned, can
be made to the dry cement for the purpose of imparting certain properties to the
mortar or to the finished stucco work produced therefrom. Additions of this kind
may consist, for instance, of colouring matters to impart from the commencement
a predetermined colour to the work to be produced.
It is clear that in this manner variously constituted dry cements can be produced,
all of which it is impossible, and indeed unnecessary, to mention.
We will proceed to specify some dry cements which contain as their albuminous
constituent the ordinary albumen of commerce (albumen of eggs, or of serum),
the use of which is attended with considerable advantages. This albumen is at
present the only albuminous substance that is manufactured on a large scale and
can be obtained at a low price. It has also the further advantage of being almost
entirely free from injurious additions such as are present in considerable quantity
in blood, cheese, glue and other albuminous substances. Moreover its percentage
of pure albumen is always practically unitorm, so that any given amount of this
albumen can always be relied upon to contain a certain amount of pure albumen
which is certainly not the case with blood and many other albuminous substanres
This albumen is therefore particularly suitable for use in carrying out our
invention, especially in those cases where it is necessary to produce mixtures
containing definite ratios of pure albumeu to lime or plaster of Paris or to a mixture
of these substances.
A mixture of powdered and dried albumen of commerce with lime and plaster
of Paris produces a dry cement which, when stirred up with water or with a dilute
solution of potash or soda, is especially suitable for producing stucco and other
work which it is desired shall have a smooth and glossy surface. When dry, the
work thus produced has a glossy surface; but to increase the gloss we recommend
that the surface of the work, after the cement has set, be repeatedly rubbed gently
with the naked hand or with a cloth or with asbestos, a little powdered tale heing
with advantage applied at the same time to increase the effect producel by the
rubbing.
We will now give, by way of example, two recipes for making dry cement such
as hereiubefore described and which have been found to give good results in

page_text: practice, but it is to be understood that we do not limit ourselves to the exact
proportions stated.
1st. 10 grammes of dry albumen which may be produced by heating albumen
obtained from eggs or serum for a long time at 40° C. are rubbed to a fine powder,
to which are added about 80 grammes of crystallized potash-alum and 10 grammes
of borax. The mixture thus produced is reduced to powder in a mortar, and with
it is mixed about 1000 grammes of plaster of Paris and about double this quantity
of powdered slaked lime.
2nd. 10 grammes of albumen are dissolved in 1 litre of lukewarm water and to
the solution are added 50 cubic centimetres of a solution of potash of 10 per cent.
strength. In this mixture about 3 kilogrammes of lime-paste that has been dried
to such an extent as to become fissured, are stirred to form a milk to which are
added 500 cubic centimetres of a cold-saturated solution of potash-alum, and
120 cubic centimetres of a cold-saturated solution of borax, and the whole is
carefully worked up together. The lime paste thus prepared is dried at a
temperature not exceeding 50° C., air being at this time excluded therefrom as far
as possible. The dried product is reduced to a fine powder and with it is mixed a
third part by weight of plaster of Paris.
We have found by experiment that floury mixtures or dry cements herein before
described when stirred up with water or with a dilute solution of an alkali, swell
up uniformly and quickly so as to produce mortar mixtures of the greatest
uniformity, only when the substances used have been not merely slightly pulverized
and mixed together, but ground with the greatest care to the finest meal or flour.
This can, of course be effected in a practicable manner, only by the aid of suitable
machinery such as mills. The extremely good result obtained by means of this
grinding may be explained in our opinion, by supposing that the dry albuminous
or proteid substances are reduced to the very finest dust and that this dust encloses
on all sides the particles of plaster of Paris which are also very fine.
... A...Amik 109
For the Applicants
W. LLOYD WISE,
46 Lincoln's Inn Fields, London, W.C., Chartered Patent Agent.
Improvements in and relating to the Manufacture of Cements for
Making Mortars suitable for the Production of Artificial Stone.
We, EUGEN WECKWARTH, of 130, Apertado, Lima, in the Republic of
Peru, at present residing at 98 Dresdenerstrasse, Berlin, in the Empire of Germany,
Doctor of Philosophy and Chemist, and MAX HOEFT of 75 Krausenstrasse, Berlin,
aforesaid, Manufacturer, 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 :-
This invention relates to the manufacture of dry cements suitable for the
It is well
preparation of mortar for use in the production of artificial stone.
known that albuminous substances or proteids, such for example as albumen,
casein, glue, blood, and cheese (hereinafter referred to generally as albuminous
substances) have a very favourable action upon the adhesive property of plaster
of Paris and also of lime, and impart to cement or mortar mixtures of which they
form part, a viscous nature that renders them extremely suitable for use when it is.
desired to produce in an easy manner, stucco or plaster work having a smooth
surface. Now an object of this invention is to obviate a drawback generally
This
attending the manufacture of cements or mixtures of the kind referred to.
drawback consists in the fact that the albuminous substances, which have always

page_text: been employed in a moist or liquid state, offer, on account of their viscous and
sometimes even gluey nature, a considerable resistance to intimate mingling with
the plaster of Paris or lime, or with a mixture of these two substances, so that the
distribution of the albuminous substances in the cement is often very far from
uniform. The consequences of this are that the finished stucco or plaster work has
not a uniform degree of hardness, and that its surface has an ununiform appearance,
which are, from a practical point of view, very serious defects.
Now in order to obviate this drawback and to produce mixtures of albuminous
substances with plaster of Paris or lime, or with both, of the greatest possible
uniformity, we proceed as follows:-
We employ the albuminous substances in a dry state: they may be either
normally dry or normally moist or liquid; if the latter, we dry them, the necessary
known precautions being taken. These substances are reduced to powder and
mixed with ground burned gypsum, that is to say, plaster of Paris, or with slaked
and dried lime that has been previously reduced to powder, or with a mixture of
plaster of Paris and lime. Or we may mix the dry non-comminuted albuminous
substances with the plaster of Paris or with the slaked and dried lime, or with a
mixture of them, and then reduce the whole to powder in any suitable manner.
A third plan is to take the albuminous substances in a moist or liquid state and
mix them intimately with lime; then to dry this mixture at a temperature up to
about 50° C.; and finally to reduce the mixture to powder. When required for
use, the cement thus prepared may be employed either alone or mixed with plaster
of Paris. Whichever of the hereinbefore described methods be followed, the
result will always be a floury dry mixture or cement which will remain unaltered
even though atmospheric air be not absolutely excluded from it, so that the manu-
facture therefore can be carried out rationally and with profit, on a large scale and
with the use of machinery, and in this consists the principal object of our present
invention.
When mixed with water, or with a dilute solution of potash or soda, these
floury mixtures or dry cements yield a mortar which is extremely uniform in
Under this
composition and is very suitable for the execution of stucco work.
terin is to be understood not only the production of such work in its strict sense,
but also the coating or covering of walls, ceilings, floors, external parts of buildings,
and the like, and also the production of castings in moulds.
In some cases it is advisable to add to the dry cement prepared as described,
a salt or salts that will combine with plaster of Paris to form an insoluble or very
slightly soluble compound with the object of increasing the hardness of the stucco
or other work after the mortar has set. As suitable salts of this kind, special
mention may be made of sulphates and double salts, such as have long been
employed for hardening plaster of Paris. An addition of boric acid, or of a
borate, particularly potassium borate, in small quantities, is also advisable in order
to delay the setting of the cement. These additions may be made in preparing the
plastic cement or mortar from the dry cement, but we recommend rather that these
additions should be made to the dry cement during the manufacture thereof.
this case the additional substances are to be added to and mixed in a dry state, and
preferably in a finely divided condition, with the mixture of substances comprising
the dry cement. But these additional substances can also be employed in a moist
or liquid condition during the manufacture of the dry cement, if no plaster of
Paris is contained in the cement. The moist mixture thus produced must then be
suitably dried and pulverized. During the manufacture of the dry cement,
plaster of Paris must not, for well known reasons, be added to a moist mixture, or
be present in a dry mixture to which a paste or liquid is added.
If the addition
In
of plaster of Paris is necessary in such a case, then the moist mixture must first
be dried.
It will be readily understood that other additious, besides those mentioned, can be
made to the dry cement for the purpose of imparting certain properties to the mortar
or to the finished stucco work produced therefrom. Additions of this kind may

page_text: consist, for instance, of colouring matters to impart, from the commencement, a
predetermined colour to the work to be produced.
It is clear that in this manner variously constituted dry cements can be produced,
all of which it is impossible, and indeed unnecessary, to mention.
We will proceed to specify some dry cements which contain as their albuminous
constituent the ordinary albumen of commerce (albumen of eggs, or of serum), the
use of which is attended with considerable advantages. This albumen is at present
the only albuminous substance that is manufactured on a large scale and can be
obtained at a low price. It has also the further advantage of being almost entirely
free from injurious additions such as are present in considerable quantity in blool,
cheese, glue and other albuminous substances. Moreover its percentage of pure
albumen is always practically uniform, so that any given amount of this albumen
can always be relied upon to contain a certain amount of pure albumen which is
certainly not the case with blood and many other albuminous substances. This
albumen is therefore particularly suitable for use in carrying out our invention,
especially in those cases where it is necessary to produce mixtures containing
definite ratios of pure albumen to lime, or plaster of Paris, or to a mixture of these
substances.
A mixture of powdered and dried albumen of commerce with lime and plaster
of Paris produces a dry cement which, when stirred up with water or with a dilute
solution of potash or soda, is especially suitable for producing stucco and other wor':
which it is desired shall have a smooth and glossy surface. When dry, the work
thus produced has a glossy surface; but to increase the gloss we recommend that
the surface of the work, after the cement has set, be repeatedly rubbed gently
with the naked hand or with a cloth or with asbestos, a little powdered tale being
with advantage applied at the same time to increase the effect produced by the
rubbing.
We will now give, by way of example, two recipes for making dry cement such
as herein before described and which have been found to give good results in
practice, but is to be understood that we do not limit ourselves to the exact
proportions stated.
1st. 10 grammes of dry albumen which may be produced by heating albumen
obtained from eggs or serum for a long time at 40° C., are rubbed to a fine powder,
to which are added about 80 grammes of crystallized potash-alum and 10 grammes
of borax. The mixture thus produced is reduced to powder in a mortar, and with it
is mixed about 1000 grammes of plaster of Paris and about double this quantity of
powdered slaked lime.
2nd. 10 grammes of albumen are dissolved in 1 litre of lukewarm water and to
the solution are added 50 cubic centimetres of a solution of potash of 10 per cent.
strength. In this mixture about 3 kilogrammes of lime-paste that has been dried
to such an extent as to become fissured, are stirred to form a milk to which are
added 500 cubic centimetres of a cold-saturated solution of potash-alum, and
120 cubic centimetres of a cold-saturated solution of borax, and the whole is care-
fully worked up together. The lime paste thus prepared is dried at a temperature
not exceeding 50° C., air being at this time excluded therefrom as far as possible.
The dried product is reduced to a fine powder and with it is mixed a third part by
volume of plaster of Paris.
We have found by experiment that the floury mixtures or dry cements herein-
before described when stirred up with water, or with a dilute solution of an alkali,
swell up uniformly and quickly so as to produce mortar mixtures of the greatest
uniformity, only when the substances used have been not merely slightly pulverized
and mixed together, but ground with the greatest care to the finest meal or flour.
This can, of course, be effected in a practicable manner, only by the aid of
suitable machinery such as mills. The extremely good result obtained by means
of this grinding may be explained, in our opinion, by supposing that the dry
albuminous or proteid substances are reduced to the very finest dust and that this dust
encloses on all sides the particles of plaster of Paris which are also very fine. It

page_text: is to be understood that all of the several materials used may be ground separately
and then well mixed, or that they may be mixed before grinding and then
comminuted together.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed we declare that what we
claim is :-
1. The manufacture of the herein described floury mixture or dry cement for
making stucco work having a smooth surface, consisting of an intimate mixture of a
finely divided albuminons or proteid substance and plaster of Paris, with or without
the addition of a substance or substances such as will tend to delay the setting of
the mortar, or to increase the hardness of the resulting artificial stone, or both,
substantially as herein described.
2. The manufacture of the herein described floury mixture or dry cement for
making stucco work having a smooth surface, consisting of an intimate mixture of a
finely divided albuminous or proteid substance, and powdered slaked lime, with or
without the addition of a substance or substances such as will tend to delay the
setting of the mortar, or to increase the hardness of the resulting artificial stone, or
both, substantially as herein described.
3. The manufacture of the herein described floury mixture or dry cement, for
making stucco work having a smooth surface, consisting of an intimate mixture of a
finely divided albuminous or proteid substance, plaster of Paris and powdered
slaked lime, with or without the addition of a substance or substances such as will
tend to delay the setting of the mortar, or to increase the hardness of the resulting
artificial stone, or both, substantially as herein described.
4. The manufacture of floury mixture or dry cement such as referred to and
for the purpose specified in the preceding claims by grinding to a fine. uniform
meal or flour, albuminous or proteid substances in a dry state with plaster of
Paris, or with slaked lime, or with a mixture of these two substances, and with, if
desired, an additional matter or matters, particularly with such as will tend to delay
the setting of the mortar prepared from the said floury mixture or dry cement, or
to increase the hardness of the resulting artificial stone, or both, substantially as
herein described.
5. The manuf.cture of a floury mixture or dry cement such as herein referred to
and for the purpose specified in the preceding claims, by mixing albuminous or
proteid substances in aqueous or alkaline solution with lime, drying the mixture, and
grinding the same to a fine uniform meal or flour either with or without plaster of
Paris, and, it may be, with an additional matter or matters particularly with such
as will tend to delay the setting of the mortar prepared from the said floury mixture
or day cement, or to increase the hardness of the resulting artificial stone,
substantially herein described.
6. The improved floury mixture or dry cement for stucco work having a
smooth surface, consisting of albumen, potash-alum, borax, plaster of Paris, and
lime combined in the dry way and substantially in or about the proportions
mentioned.
7. The improved floury mixture or dry cement for making stucco work having
a smooth surface, consisting of albumen, potash, lime, potash-alum, and borax
combined in the wet way, then dried, and mixed with plaster of Paris, substantially
in or about the proportions mentioned.
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