AN IMPROVED PROCESS FOR SIZING PAPER AND TEXTILE FABRICS, WHICH IS ALSO APPLICABLE TO THE MANUFACTURE OF PARCHMENT-PAPER, LEATHER-BOARD, AND OF BOARDS USEFUL FOR MANY PURPOSES FOR WHICH WOODNOW
Year: 1883

page_text: LETTERS PATENT to Charles Weygang, of 7 Hermitage Villas, Childs Hill, in
the County of Middlesex, Manufacturers Agent for an Invention of AN
IMPROVED PROCESS FOR SIZING PAPER AND TEXTILE FABRICS, WHICH IS ALSO
APPLICABLE TO THE MANUFACTURE OF PARCHMENT-PAPER, LEATHER-BOARD,
AND OF BOARDS USEFUL FOR MANY PURPOSES FOR WHICH WOOD IS NOW
USED
PROVISIONAL SPECIFICATION left by the said Charles Weygang at the
Office of the Commissioners of Patents on the 3rd May 1883.
CHARLES WEYGANG, of 7 Hermitage Villas, Childs Hill, in the County of
Middlesex, Manufacturers Agent, "AN IMPROVED PROCESS FOR SIZING PAPER
AND TEXTILE FABRICS WHICH IS ALSO APPLICABLE TO THE MANUFACTURE OF
PARCHMENT PAPER, LEATHER BOARD, AND OF BOARDS USEFUL FOR MANY PURPOSES
FOR WHICH WOOD IS NOW USED,"
The principal object of this Invention is to size paper in the pulp with animal
size or starch, or the two combined, by precipitating the glue or starch in such a
manner that their valuable binding property is not materially injured so that the
fibres are effectually united and the paper thus rendered very strong, also that at
the same time no loss or waste of the sizing materials is incurred; Also to
chemically cause an earthy precipitate in combination with the sizing for the
purpose of filling and improving the appearance of the paper or fabric.
Hitherto the better classes of papers have been sized by passing the otherwise
finished sheets through a solution of animal size, which is not only an expensive
process, but also imperfect, as in some cases the size does not thoroughly penetrate
the paper.
3
In the process heretofore in use saponified rosin and glue are used in combi-
nation in the pulp, the Action depending upon the fact, that when Alumina is
added to the pulp the resinous soap is precipitated in an insoluble condition and
takes the glue with it. The glue however is not precipitated by this process but
only mechanically combined with the resin, much therefore remains free in solution
which must be washed away and wasted in manipulating the pulp. Besides
-1.

page_text: which the exceedingly fine mechanical combination of the rosin and glue greatly
deteriorates their individual cohesion, the two bodies being foreign to each other,
and so far as strength is concerned this sizing can hardly be an advantage over the
common rosin alone.
Rosin size alone imparts but very little stength to the paper, and is only of
value to render the paper hard and damp proof, so as to be suitable for writing,
printing, and packing.
Starch in the manner in which it is generally used is imperfect for many
reasons, the principal one being that the starch is not brought to a thorough state
of solution and therefore its real adhesive property is not brought into play, and
it does not impart to the paper the desired stability and crispness.
All the above difficulties and imperfections are avoided with the present
invention which I now proceed to describe
For the purpose of sizing with animal glue I choose the glue of quality
appropriate to the nature of the paper to be made-I dissolve it in the ordinary
manner and add the solution to the paper pulp in the beating engine-I then
make a solution of one or more astringent metallic salts of nature appropriate to
the quality of the paper to be made (or these salts may be dissolved together with
the glue) and I add the result to the pulp in the beating engine.
For white papers I use the sulphate of Zinc and the sulphate of Alumina the one
or the other may be used alone but better results are obtained by employing them
together. I then add to the sized pulp either in solution or fine powder a Caustic
Alkali, such as the potassium or sodium hydrate.-This causes the glue to
precipitate in a peculiar filamentous and flocculent condition, mostly on to the
fibres, the free floating of the fibres is not hindered thereby and the peculiar form
of the precipitate assists the felting of the fibres besides causing them to unite
firmly when the paper is finished, the usual waste of glue is thus avoided because
there is no glue left in solution, neither is it in an impalpable state of division in
the pulp, such as would pass through the meshes of the web or blanket.
Although the glue is in an insoluble state in the pulp it still retains to a great
extent its natural properties whilst in a bydrated condition and the pulp can thus
be made to become perfectly homogeneous and applicable for making parchment
paper, leather boards, boards for building, furniture and many other purposes.
For this purpose the water which is now foreign to the precipitated glue must be
pressed out of the paper or board as much as possible, so as to allow the molecules
of glue to unite in one solid body.
Heat is necessary for this purpose as well as pressure and in the case of paper
this can be arranged on the drying cylinders of the paper machines, but in the
case of thick boards which are made in thin layers upon a drum, the thin layer. of
pulp can be heated as it passes along by means of steam below the blanket. The
boards are then subjected to gradual pressure whilst they are in a hot state.
I have mentioned the sulphate of Zinc and Alumina above because these are
particularly adaptable to the purpose, but certain other astringent metallic salts
or Acids may be used, and instead of precipitating with a caustic alkali, an Alkaline
earth may be used, as for instance the the hydrate of limę.
Most papers contain a certain amount of mineral matter which is used for the
purpose of filling and improving the appearance of the paper, I combine this
purpose with my sizing process in a much more effectual way by the following
method. I mix a soluble salt of Baryta with the glue in the beating Engine,
then add a salt containing sulphuric acid by preference an astringent metallic salt
such as the before mentioned Zinc and Aluminia Sulphates; for some purposes the
Sulphate of Magnesia may be used with advantage and under certain conditions a
sulphide or a sulphite may be employed in combination with a small quantity of
Chlorine. This will cause the Baryta to precipitate as barium sulphate (blanc
fixé) throughout the pulp and in the pores of the fibres in an exceedingly fine
condition and upon adding a caustic alkali the precipitate will form as before.
described. Instead of Baryta, a salt of Lime may be used for some purposes.

page_text: For the purpose of sizing with starch or flour, I dissolve starch or flour
thoroughly in a dilute solution of Caustic Alkali. I add the requisite quantity
to the pulp in the beating engine with a small quantity of a soluble silica, and
precipitate with an alkaline earth, such as magnesia, baryta, or lime, and I may
employ these separately or in combination-and for some purposes I may ues a
basic metallic salt. This is a very strong sizing, perfectly white and imparts to
papers a good metallic ring and crispness. For some purposes the Silica may be
omitted. The Starch by this process is rendered insoluble and may be made
to become perfectly homogeneous by similar treatment as described in the glue
process.
The above processes are more or less applicable for sizing textile fabrics. but the
method generally preferable for this purpose is to mix a salt of Baryta with the
glue or starch then add a salt containing sulphuric acid and immerse the fabric
into this compound. The following is an example giving excellent results. Glue
mixed with soda byposulphite, then barium chloride is added, and then an
astringent metallic salt, such as the sulphate of alumina, the result is a jelly which
when dry is insoluble, this would also be useful for surfacing paper or textile
fabrics and when applied rather thick and mixed with colors it would give a
leathery appearance to the material.
The two methods of sizing, that is the glue and starch process may be blended
and used together with advantage.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Charles Weygang in the Great Seal Patent Office on the
3rd November 1883.
CHARLES WEYGANG of 7 Hermitage Villas Childs Hill in the County of
Middlesex Manufacturers Agent AN IMPROVED PROCESS FOR SIZING PAPER
AND TEXTILE FABRICS WHICH IS ALSO APPLICABLE TO THE MANUFACTURE OF
PARCHMENT PAPER, LEATHER BOARD, AND OF BOARDS USEFUL FOR MANY PURPOSES
FOR WHICH WOOD, IS NOW USED
"
The principal object of this invention is to incorporate, animal glue starch or
flour with a fibrous pulp prepared by paper machinery by precipitating the glue
starch or flour in the fibrous pulp and treating these materials in such a manner as
to render them more or less impervious to water whilst not materially injuring
their valuable binding property so that the fibre with which they are combined
may be caused to unite and by varying the proceedings as hereafter described the
invention may be applied to the sizing of ordinary paper or for the production of
material applicable for some of the many purposes for which parchment leather
wood horn bone and stone &°. are employed.
For the purpose of sizing with animal glue I dissolve the same in any convenient
manner and I add the solution to the fibrous pulp in the beating engine or other
suitable mixing apparatus
I then add one or more astringent metallic salts of nature appropriate to the
kind of material to be produced I then add a caustic alkali or an alkaline earth or
a salt of an alkali or an alkaline earth taking care that the acid of the metallic
salt is in excess or that otherwise an acid is in excess the object being to cause the
formation of a nascent oxide or an acid or an interchange of elements in the glue
in solution whereby this is energetically attacked and precipitated in the fibrous
pulp
Instead of first adding the acid metallic salt I may in some cases add the alkaline
salt first and under certain circumstances I can mix the separate chemical agents
together and add the mixture to the pulp and size in the beating engine
In some cases I mix one or more of the chemical agents employed with the size
before I introduce the latter into the beating engine and sometimes I mix the glue
in a precipitated form with the pulp in the beating engine Sometimes I mix the
glue with certain chemical agents which do not precipitate it but only thicken it
and I incorporate this thickened glue or size with the fibrous pulp whilst this is
being formed into sheets
Instead of employing metallic salts I may for some purposes use non-metallic
elements which have chemical affinity for the glue
Having in the above given an outline of my invention I now describe the various
methods for carrying the same into effect
For sizing ordinary paper the practical manufacturers will be able to proceed
from the following details
For special purposes the fibres and the quality of the glue are chosen according
to the nature of the material to be produced Thus for very strong purposes such
as for substitutes for leather the strongest classes of fibres are employed such as
hemp china grass &°. The fibrous materials are treated in the same manner as in
paper making and in beating are kept of greater or shorter length according to the
material to be produced thus if the material is to stand great tensile strain the
fibres are kept of as great a length as possible
The glue is also chosen according to the material to be produced for instance for
material to take the place of leather I prefer to employ such as is made from skin
and hide pieces
For almost all other purposes it is chosen according to the color
required I prefer to use the glue in the form of size the quantity varying for the
different purposes for instance for the purpose of making material to take the place
of leather a good proportion is about three Cwt of size of average consistency to

page_text: about one Cwt of fibrous pulp reckoning the latter in dry weight For material to
be used in the place of horn bone and such like purposes I use from five to six Cwt
of size to about one Cwt of fibrous pulp (dry weight)
For most other purposes
from one and a half to two and a half Cwt of size is usually employed
However as such a variety of material can be produced I do not confine myself
in any way to the proportions given above
When the glue has been dissolved I incorporate it with the fibrous materials in
the beating engine after the fibrous material has been beaten to the requisite
condition and I then proceed to precipitate the glue by either of the following
processes
No. 1. I add for every Cwt of size in the beating engine about five lbs of an acid salt
of zinc or alumina in a dry state or in solution I prefer the sulphates of these
metals and I can use them either separately or combined in a proportion of about
two lbs of the sulphate of zinc and about four lbs of the sulphate of alumina―
I now add a salt of an alkali until no more precipitate will form and I can employ
a caustic alkali such as soda hydrate in a proportion of about one lb to every five lbs
of metallic sulphate employed but I prefer to use a sulphite or a sulphate of an
alkali and I find that the sulphate of ammonia in a proportion of about eight lbs to
every Cwt of size gives the best result I prefer to add the chemicals in a state of
solution but they may be added in a dry state in which case I first reduce them to
powder
Instead of mixing the metallic salts with the size in the beating engine the same
results are obtained by mixing them with the size previous to its introduction into
the beating engine Also the same results are obtained by mixing one of the
metallic salts with the size and combining the other with the alkali Thus I would
add the sulphate of alumina with the size and to a solution of sulphate of zinc
I would add a caustic alkali until the precipitate formed is re-dissolved and this
mixed solution I use in the same manner as the alkaline salt alone.
No 2. I add a solution of ammonia chloride to the size in the beating engine or
I incorporate the ammonia chloride with the size before putting the latter into the
beating engine I employ a proportion of about seven lbs of ammonia chloride for
every Cwt of size and when the size and the salt are thoroughly mixed with the
pulp I add about three lbs of Bichromate of Potash in solution for every Cwt of
size I then add a sulphate of an alkali in a dry state or in solution and I prefer
to employ the sulphate of ammonia which is added until the size is all precipitated
the proportion being about seven lbs of sulphate of ammonia for every Cwt of size
For the purpose of improving the precipitate I add a small quantity of an acid salt
of alumina in solution such as the sulphate of alumina in a proportion of about
two lbs to every Cwt of size
No 3 and 4-Instead of employing Bichromate of Potash as just described I can
employ with advantage sulphate of copper or iron alone or together or either one
combined with an acid salt of zinc or alumina The proportion of the copper or
iron salt is about five lbs of either for every Cwt of size or if used together about
two and a half lbs of each or if employed with zinc or alumina the proportion of
the copper or iron salt would be about four lbs and two lbs of the zinc or three lbs
of the alumina salt I precipitate with a salt of an alkali as before mentioned and
I prefer to employ the sulphate of ammonia or soda hyposulphite or these two
combined that is I first add a solution of soda hyposulphite in about the same
proportion as the acid metallic salts employed and then ammonia sulphate in a
proportion of about one third of the soda hyposulphite employed
No 5. I dissolve ammonia chloride with size as before mentioned and then sulphate
of alumina in a proportion of about six lbs to every Cwt of size and when
thoroughly incorporated with the pulp in the beating engine I add for every Cwt
of size about two lbs of an alkaline chromate such as chromate of Potash in
solution For the purpose of improving the precipitate I may finally add a small
quantity of ammonia sulphate in a proportion of about two lbs for every Cwt
of size,

page_text: N° 6. Instead of employing ammonia chloride alone as described I sometimes
combine it with calcium sulphate and hydro-chloric acid For this purpose I first
dissolve the ammonia chloride in water and then I add about six lbs of calcined
calcium sulphate to every six lbs of ammonia chloride and then I add about
three lbs of hydro-chloric acid I allow the mixture to remain a few hours before
using stirring it from time to time and I then employ it as I would the ammonia
chloride alone precipitating the glue in the same way as already described.
In employing this mixture however I precipitate with very good results by using
ammonia sulphate alone in a proportion of about twelve lbs for every Cwt of size
without employing an astringent metallic salt
In all cases described above the ammonia chloride is principally added for the
purpose of rendering the glue less brittle-where hardness is no object such as for
material to be used in the place of horn bone wood & the ammonia chloride is
omitted.
N° 7 To a strong solution of hydro chloric acid I add a dilute solution of an
alkaline silicate until the slightest signs of precipitation appear Of this solution
I add from one and a half to two and a half gallons to every four gallons of size
contained in the beating engine
I then add for every gallon of acid silica used about an equal quantity of soda
hyposulphite in a saturated solution and when thoroughly mixed I add a small
proportion of ammonia sulphate for the purpose of improving the precipitate For
this purpose a proportion of two-three lbs being sufficient
N° 8 Instead of employing an acid silicate I may under certain circumstances
employ an alkaline silicate for which purpose I prefer to proceed as follows:
I mix with every cwt of size from one quarter to three quarters Cwt of an
ordinary solution of an alkaline silicate such as silicate of soda incorporate the
size and silica with the pulp in the beating engine and I now add a compound of
chlorine by preference ammonia chloride of which I add a solution to the matter
in the beating engine until no more precipitate forms
Instead of employing a salt of chlorine I can use with very good results a small
quantity of bydro-chloric acid in a proportion of about one eighth of the weight of
silicate employed and I then add ammonia sulphate until no more precipitate
will form
.
N° 9 I employ a salt of an alkaline earth and I prefer to use the calcium chloride
with hydro-chloric acid in excess. that is to a saturated solution of ordinary calcium
chloride I add from one half to an equal quantity in bulk of hydro-chloric acid-
Of this solution I add about one and a half gallons to every four gallons of size
contained in the beating engine I then add a saturated solution of soda
hy posulphite in a proportion of about two gallons to every one and a half gallons
of calcium chloride and acid employed and when thoroughly mixed with the size and
the pulp I add a small quantity of ammonia sulphate for the purpose of improving
the precipitate
N° 10 In cases where it is desired to make a very opaque material of a good
color I employ a soluble salt of Baryta or calcium in conjunction with a sulphate
or a sulphite
For this purpose I add to every Cwt of size either before or after its introduction
into the beating engine from six to ten lbs of the soluble salt of the alkaline earth
and I prefer to employ for this purpose barium chloride and after being thoroughly
mixed with the size in the beating engine I add either in a dry state or in
solution a sulphate or a sulphite prefer to employ sulphate of alumina in a
proportion of about four lbs to every six lbs of the salt of the alkaline earth
employed and after being thoroughly mixed I add a small quantity of a caustic
alkali in solution such as soda hydrate in a proportion of about half lb to every
six lbs of baryta chloride employed Or instead of employing a caustic alkali I
can employ an alkaline sulphate in which case I prefer to use the ammonia
sulphate
No 11 Instead of precipitating the glue in the beating engine I may precipitate it

page_text: but not with such good results before it is incorporated with the fibrous pulp in
the beating engine by any of the above named processes or with bichromate of
potash in conjunction with any other astringent metallic acid salt such as the
sulphate of alumina or zinc In this case I can add the precipitating agents
separately to the dissolved glue in any suitable apparatus or I can mix the
precipitating solutions together before adding them to the size thus, in employing
process N° 2 I can first add a solution of three lbs of Bichromate of Potasli
to every Cwt of size and then a solution of sulphate of ammonia until the whole is
precipitated or I may mix the two solutions in a proportion of three lbs of
Bichromate of Potash and from eight to ten lbs of ammonia sulphate together
and add the same until all the size is precipitated I add the solid precipitate
formed to the pulp in the beating engine and allow it to rub or beat fine with
the pulp
N° 12. Instead of precipitating the glue in the pulp or previous to its introduction
into the beating engine I may in the case of paper or boards which are made in
thin layers upon a drum mix the chemical agents with the size in such a manner
that the size becomes very thick without precipitating I prefer for this purpose
an alkaline chromate and an acid salt of alumina for instance chromate of potash
and sulphate of alumina I mix a solution of the two salts until the mixture
becomes turbid that is until the mixed solution is almost neutral the acid however
supervening of this mixture I add about one gallon to every four gallons of size
in solution stirring well I then introduce the thickened size into a conically shaped
box fitted with a steam pipe for the purpose of keeping the size fluid the box is
placed above the drum of the paper machine extending its whole length with the
narrow end downwards the box is open at the bottom the aperture being covered
by a roller which rests upon the drum and revolves with the same giving off the
glue taken from the box to the layer of pulp upon the drum-Flaps attached to
the box at each side of the roller are drawn together or opened by means of screws
and thus by opening or pressing on the roller regulate or stop the flow of size
from the box
The glue in material made in this manner being homogeneous such material does
not require the treatment with heat as hereafter described
Of course the above described process may be varied or blended according to
circumstances and although to the best of my experiences they are the most
applicable I do not strictly confine myself to them-Taking for instance process N° 2
I could substitute but not with such good results sulphate of zinc alone or with
other astringent acid salts in the place of the sulphate of ammonia
Instead of adding the chemical agents separately to the size I may in some
instances add all the chemicals together and precipitate with the mixed solution
thus in the case of chromate of potash and sulphate of alumina I can mix a
solution of each salt together until the mixture becomes turbid and I then add
this mixed solution to the size in the beating engine until all the size is
precipitated which may be ascertained in all cases by filtering some of the liquid
from the pulp into a glass and testing it with some of the precipitating solution
employed If the liquid remains clear upon the addition of some of the precipitating
solution all the size is precipitated but if it becomes cloudy more of the precipitating
solution must be added.
Instead of employing chromate of potash very fair results are obtained by
employing an acid salt of zinc and alumina in combination and adding to a solution
composed of equal parts of these salts a caustic alkali until the mixture is very
turbid but still of an acid reaction I would employ for this purpose the sulphate
of zinc and of alumina and the soda hydrate
Although the precipitated glue is in an insoluble or very difficultly soluble
condition in the fibrous pulp it retains in most cases its strong adhesive property
and I make use of this for the purpose of rendering the material manufactured'
perfectly homogeneous and very strong as required for the various purposen
described

page_text: For the purpose of merely sizing paper in the ordinary sense the usual treatment
which paper receives in the course of manufacture is sufficient but for special
purposes I proceed as follows:
In order to render the particles of glue contained in the fibrous material adhesive
I heat the sheet or board directly or soon after it leaves the machine that is whilst
fresh and wet to about 180 to 220° F in any convenient manner.
I may expose
the material for this purpose on heated surfaces or place it in heated Chambers
fitted with suitable shelves When the material is thoroughly heated throughout I
subject it to pressure between felts or other porous fabrics for the purpose of
expelling the water and allowing the particles of glue to unite with each other
The pressure is brought to bear very gradually upon the material so as to allow
the water to pass out without disturbing the felting of the fibres
The material is allowed to remain in the press until no more water escapes and
it is then hung up and dried in suitable rooms which may be slightly warmed for
the purpose of causing a dry atmosphere
The processes described under N° 1. 2. 3. 4. 5. 6. 7. 9 and the corresponding
processes under N° 6 and 11 are adaptable to this method of rendering the
material homogeneous The omission of the ammonia chloride as mentioned does
not hinder the material from becoming adhesive
Glue treated by the processes N° 8 and 10 does not become adhesive by heat
but in drying the particles of glue set to a solid mass Therefore material made by
processes No 8 and 10 need not to be subjected to heat but it is well to subject it
to a moderate pressure
Also in cases where I precipitate with a salt of an alkaline earth instead of with
a salt of an alkaline metal for instance if I substitute hydrate of lime for sulphate
of ammonia in process N° 1 the material produced is not effected and such material
need not be subjected to heat but merely to pressure
The processes under N°* 1. 7. 8. 9 and 10 and the corresponding process under
No 6 and 11 produce a colourless or almost colourless sizing and these are therefore
adaptable where a white material is to be produced and for sizing white papers in
general of these the processes N° 1 and the corresponding process under N° 6
and 11 produce the strongest sizing and are adaptable for purposes accordingly
such as parchment paper In cases where the salts of chrome copper or iron are
employed the size is distinctly colored.
For the purpose of making a substitute for leather the process N° 2 and 5 and
the corresponding processes under N° 6 and 11 give the best results so far as my
experiences go These processes are also adapted for making substitutes for horn
Material manufactured to take the place of horn is subjected to an extra pressure
after it is dry For this purpose I heat the material when perfectly dry to about-
200 to 240° F and I then place it between metal plates and into an hydrolic press
and subject it to a pressure of one hundred and sixty tons or more and I leave the
material under full pressure for three hours or upwards Such material when
finished can be bent to any shape when heated like natural horn With all the
processes described the glue is rendered more or less insoluble but with the
exception of N 7 and 8 and in cases where hydrate of lime has been employed
for precipitating the glue, it absorbs when placed in water a certain amount of the
same without however losing its strength
N° 7 produces a sizing which when dry is perfectly foreign to water or damp
and is therefore applicable for all kinds of building purposes being especially
adapted for such purposes as this process renders the material almost fire-proof It
is also useful for a great number of purposes where wood bone stone & are
employed
For the purpose of imparting great softness to the material such as is required
for most leather purposes I subject it to a bath of glycerine diluted with from
three to five times its bulk of water It is of course understood that the material
is subjected to this bath when it is finished and dry It is allowed to remain in
the bath until saturated and it is then again dried in any convenient manner The

page_text: material produced by such processes as N° 7 and 8 is not adaptable for this purpose
as will be naturally understood being quite unaffected by moisture Also material
which has been heated and pressed for making substitutes for horn is not adapted
for this purpose
Material manufactured to take the place of leather after the processes described
may be carried in a similar manner as natural leather
Instead of heating and pressing the material as described for the purpose of
rendering it homogeneous I sometimes omit these operations and merely dry the
material as it comes from the machine Such material is porous and slightly spongy
and may if required be saturated with oils or fats by inmersion in oils or fats or
by rubbing these into the material
For the purpose of sizing with starch or flour. I suspend the starch or flour in
water and I add a solution of a caustic alkali until the mixture becomes transparent
and gelatinous and I add of this dissolved starch or flour the requisite quantity to
the fibrous pulp in the beating engine Instead of dissolving the starch with a
caustic alkali it may be dissolved by boiling
For ordinary sizing purposes the practical paper maker will be able to adjust
the proportion of starch or flour to his requirements For special purposes rather
more will be required than for ordinary sizing thus if the material is to be.
employed for some purposes where wood and bone are used a good average
proportion is about ten lbs of dry starch or flour for every Cwt of dry pulp
Instead of dissolving the starch or flour before its introduction into the beating
engine I may mix it in a dry state with the pulp in the beating engine and when
thoroughly mixed with the fibrous pulp I add about five lbs of caustic soda in
solution for every ten lbs of starch or flour and I proceed as follows:
I add to the starch or flour and the pulp in the beating engine about twenty lbs
of a solution of silicate of soda or other alkaline silicate for every ten lbs of starch
or flour employed and I then add a solution of a salt of an alkaline earth such us
calcium or barium chloride or magnesia sulphate until no more precipitate will
form
Or, instead of an alkaline earth I may employ a salt of chlorine by preference
ammonia chloride for the purpose of precipitation For purposes where a stronger
sizing is required I precipitate with an acid metallic salt omitting the silica I
prefer to employ the chloride of zinc or the sulphate of copper a solution of either
of which salts 1 add to the starch or flour and pulp in the beating engine until no
more precipitate will form
may
also precipitate with very good results with an acid solution of silica
prepared with hydrochloric acid as hereinbefore described
If the processes are employed for sizing paper in the ordinary sense the paper is
finished off in the usual manner but for special purposes when the material is to
be employed for some of the purposes named I subject it to a very gradual pressure
whilst it is still in a wet state, that is, soon after it leaves the machine and I
then dry it by exposing it in any suitable rooms in the same manner as the
glue sized material. Still better results are obtained by partially drying the
material before subjecting it to any pressure and when about one half or three
fourths dry to subject it to a strong pressure between soft porous material allowing
it to remain under full pressure for three hours or upwards
In employing copper sulphate heat may be used to facilitate the adhesion of
the particles of starch in the same way as described under the animal sizing
process
The copper sulphate colours the starch or flour a bright green or blue the other
processes produces almost a colourless sizing

page_text: (1) By precipitating the glue in the beating engine or other equivalent mixing
apparatus by adding one or more salts of an astringent metal to the glue in
solution and then adding independently one or more salts of an alkali or alkaline
earth or vice versa substantially as described
(2nd) By precipitating the glue before it is mixed with the fibrous pulp and then
adding the solid precipitate to the fibrous pulp in the beating engine substantially
as described
(3rd) By precipitating the glue in the beating engine or other equivalent mixing
apparatus or otherwise incorporating the glue with the fibrous material by the use
of Chromate of Potash or other alkaline chromate in combination with an acid
salt substantially as described
2ndly The use of Bichromate of Potash in conjunction with sulphate of ammonia
alone or with other astringent acid salts so far as this relates to the sizing
with animal glue of any material made on similar principles as paper is
manufactured
3rd The use of an acid salt of zinc or combination with a salt of alumina and a
salt of an alkali so far as this relates to the sizing with animal glue any material
made on similar principles as paper is manufactured
4th The use of an acid solution of silica in any combination so far as this relates to
the sizing with glue gum or starch or their derivatives any material made on similar
principles as paper is manufactured
5th The use of an alkaline solution of silica in combination with any compounds
of chlorine or an alkaline sulphite or sulphate so far as this relates to the sizing
with glue gum or starch or their derivatives any material made on similar principles
as paper is manufactured
6th The use of calcium or Barium chloride in combination with an alkaline
sulphite or sulphate so far as this relates to the sizing with animal glue any material
made on similar principles as paper is manufactured.
7th The use of ammonia chloride so far as this relates to the sizing with
animal glue any material made on similar principles as paper is manufactured
8th The use of ammonia sulphate and alkaline sulphites for the purpose of
precipitating animal glue for sizing any material made on similar principles as
paper is manufactured
9th The use of calcium sulphate combined with a salt of chlorine and
hydrochloric acid or with either alone so far as this relates to the sizing
with animal glue any material made on similar principles as paper is
manufactured
10th The process of sizing any material made on similar principles as paper is
manufactured with starch or flour dissolved with a caustic alkali in combination
with silica and an alkaline earth or in combination with an acid inetallic salt
11th The use of an acid salt of copper or chloride of zinc for the purpose of
sizing with starch or flour any material made on similar principles as paper is
manufactured
12th The process of making homogeneous any material made on similar principles
as paper is manufactured and incorporated with precipitated animal glue by
applying heat and pressure substantially as described.
In witness whereof the said Charles Weygang hath hereunto set his hand
and seal this second day of November in the year of our Lord One thousand
eight hundred and eighty three.