IMPROVE- MENTS IN THE TREATMENT OF SHORT COARSE ANIMAL HAIR
Year: 1879

page_text: LETTERS PATENT to Ezekiel Luther Hamilton, of the City of New York,
United States of America, at present residing at the Golden Cross Hotel,
Charing Cross, in the County of Middlesex, for the Invention of "IMPROVE-
MENTS IN THE TREATMENT OF SHORT COARSE ANIMAL HAIR." A communi-
cation from abroad by Gideon Hamilton, of the City of Brooklyn, in the State
of New York. United States of America.
PROVISIONAL SPECIFICATION left by the said Ezekiel Luther Hamilton at
the Office of the Commissioners of Patents on the 14th October 1879.
EZEKIEL LUTHER HAMILTON, of the City of New York, United States of America,
at present residing at the Golden Cross Hotel, Charing Cross, in the County of
Middlesex. "IMPROVEMENTS IN THE TREATMENT OF SHORT COARSE ANIMAL HAIR."
[A communication from abroad by Gideon Hamilton, of the City of Brooklyn, in
the State of New York, United States of America.]
It is the object of this Invention to obtain from short coarse animal hair a
product which can be spun or woven in a greater or less degree the felting
properties characteristic of wool or fur, and also possessing in a greater or less
degree the curl and spring suitable for and adapted to upholstering purposes, thus
furnishing a cheap substitute for wools and furs in various manufactures in which
they are used alone or together, or mixed with other fibres and a cheap material
useful for mattresses and other upholstery, thereby extending the economical use of
a fibre, to which improved textile felting and other useful properties have been
imparted, to many branches of the arts in which the cost of wools or furs would
be restrictive or prohibitory; and this object is accomplished by subjecting to the
novel process herein after described the raw material mentioned, to wit, short
coarse animal hair, which in its normal or commercial condition does not possess
these improved properties.
It has been discovered, and by a series of experiments demonstrated, that the
short coarse hair which forms the coats of certain animals, to wit, the hair of cows,
calves, bulls, oxen, and horses, which either in its ordinary or in its commercial

page_text: condition does not possess the characteristics of the finer animal fibres which are
classed as furs or wools can, by a certain chemical treatment, have such charac-
teristics imparted to it to such an extent as to make it amenable to the same
treatment as wools or furs, and to render it available for uses similar to those which
heretofore have been peculiar to wools or furs, that is to say, such hair by said
treatment is refined and softened, is made lustrous, and waved, curled, crimped,
or twisted to a greater or less degree according to the particular purpose for which
it is intended to be used, and rendered capable of being felted, spun, woven
carded, and formed into bats or wadding. I advisedly define the hair to be thus
treated as short and coarse, because I do not mean to allege that the Invention is
applicable to the long coarse bristle like hair obtained from the manos and tails of
horses or from the tufts of the tails of cows, calves, bulls, or oxen.
As well as can be determined some of the qualities imparted by this chemical
treatment are derived from a change which takes place in the fibres, and which
either consists of the developement on the exterior of said fibres of serrations or
imbrications, like those peculiar to wools or furs, or else imparts to the treated
fibre some equivalent irregularity (not incident to their natural state) which makes
them susceptible of substantially the same felting, spinning, and weaving processes
to which wools or furs are subjected. In addition to this change in its surface the
fibre derives from the process a spiral, wavy, curly, or twisted form, which may be
made more or less positive by a modification of the treatment according to the
purposes for which the product is to be used for example, the greatest care being
imparted to fibre intended for mattresses and other upholstering purposes, while a
less degree is more comformable with the requirements of felting and still less with
those of spinning.
The treatment also rids the fibre of its coarse, harsh, stiff, horny, dull, unyielding,
and straight character, and gives it fineness, flexibility, softness, and lustre.
To obtain the results above set forth the hair is treated with alkaline solutions,
as herein after more fully explained.
In a suitable vessel I prepare an aqueous solution of caustic soda or of caustic
potash, of a strength measuring about one tenth of one degree of Beaumé's hydro-
meter. I then take animal hair of the kind herein before specified, in the condition
in which it is found on sale (or, if it is unduly loaded with foreign matters, I
previously open it out and wash it with water) and immerse it in the bath
described, and boil it therein for from three to ten minutes, or in a bath of about
one degree Beaumé's at a temperature of, say 160° to 170° Fahr., the hair would be
left from fifteen to twenty minutes.
Considerable variation may be made, if found requisite in particular cases, in the
strength of the solution, the temperature of the bath, and the time during which
the hair is subjected to the treatment. With a stronger solution a lower tempe-
rature would produce the result within the same time, with a higher temperature
the same strength in the bath would produce the result in less time, and with a
weaker solution or a lower temperature the time must be extended.
These variations cannot be defined more exactly than I have above mentioned
because they will depend upon the strength of the solution, the maintenance of the
temperature at a uniform height, or, in some instances, upon the condition of
the hair. The operator can determine whether the process is proceeding properly
by taking from time to time a sample out of the bath and washing it in water
slightly acidulated with sulphuric or other acid, and when this test shows that the
fibre has acquired the proper reduction, fineness, and curl, the mass should be
removed at once from the bath and plunged into a bath of cold water, so as to
arrest the action of the caustic solution and leave the product of the process in its
proper condition, this washing being continued, with a change of water if necessary,
until the solution is thoroughly washed out. The product is then dried and is
ready for use.
Another variation in the process above described will be governed by the use

page_text: for which the particular product is designed. For spinning and weaving purposes,
or for forming into bats or wadding, a less curly condition of the product is
desirable, while for mattresses and other upholstering uses more curl and spring
are desirable. To increase the degree of curl it is only necessary to leave the hair
in the same solution a little longer, but not to extend the period of immersion in
conjunction with a stronger solution or a higher temperature, as this would tend to
deteriorate the fibre. Where softness, lustre, and pliability are desirable with only
a slight degree of curl I use the above described process, but with a weaker solution
and at a lower temperature and for a longer time than in the instance specified, that
is, a bath having a strength of, say one half of one degree of Beaume's hydrometer,
at about 150° Fahr., and for about forty five to sixty minutes. And if an extreme
degree of softness, lustre, and pliability are desired 1 immerse the fibro in a cold
aqueous solution of caustic soda or caustic potash of a strength measuring about
five degrees of Beaumé's hydrometor for from twenty four to forty eight hours, or
even longer, or in a cold aqueous solution of caustic soda or caustic potash,
measuring about ten degrees of Beaume's hydrometer, for from four to six hours, or
even longer; or if the strength of the said cold solution be increased to fifteen
degrees Beaumé's hydrometer the time will be reduced so as not to exceed from
about two to four hours. In all these cases such modifications being observed as
are required by the refractoriness of the fibre and with due observance of the
energy of the chemical action of the bath as affected by the temperature of the
atmosphere, this action being stimulated by hot weather and retarded by cold.
The formula above given are indicated for the cold treatment in an atmosphere
of from sixty to eighty degrees Fahr., and a solution made with soda or potash of
about sixty per centum of causticity.
If desirable, the temperature of the solution may be reduced or raised and
maintained at a substantially uniform degree by artificial cold or heat, as, for
example, by means of ice or fires.
As in the hot treatment, so in this cold treatment, the fibre must be watched
and its condition tested from time to time in acidulated water, and the fibre
should be removed from the solution or caustic bath when the test indicates that
it has attained the proper condition and should then be thoroughly washed in
water.
Instead of using an aqueous solution of caustic soda or caustic potash, as above
described, I use an aqueous solution of caustic lime in the following manner :-I
make a cold saturated solution of caustic lime and bring this solution to a tempe-
rature of about 170° Fahr., and then immerse the hair in it for a period of about
three to four hours; or I bring this solution to a boiling point, then immerse the
hair in it and let it boil for a period of from ten to twenty minutes, testing it from
time to time with acidulated water, as above described, and when it has reached
the proper condition I wash it in water, as above described.
This Invention further consists in treating the above described product of the
above described process, whether treated in the hot or the cold caustic solution,
and either before or after it has been washed in water, with a further washing in
a cold weak acid solution known as a "sour," or rather in a cold water bath slightly
acidulated with an acid, such as sulphuric, muriatic, or acetic, though sulphuric or
muriatic is preferred for this purpose. This acid bath neutralizes any traces of
the caustic soda, or caustic potash, or caustic lime not removed by the water bath,
increases the softness and lustre of the fibre, leaving its curl and spring unimpaired
and retrieves and preserves the strength of the fibre, and prevents deterioration in
it in cases where the action of the first bath has been too energetic. The hair
after being removed from this acidulated bath or "sour" need not be washed, but
is simply allowed to dry in a warm room or by currents of warm or cold air.
I have specified caustic soda, caustic potash, or caustic lime as the best ingredients
known to me for the solution forming the first bath in this process, and as
imparting to the bath in the most satisfactory and efficient manner the causticity

page_text: to which I mainly attribute the result of the process; but I contemplate using any
chemical equivalents of caustic soda, or of caustic potash, or of caustic lime as
substitutes therefor, whether such equivalents be simple or compound chemical
equivalents; and I contemplate also using solutions which, although not of them-
selves sufficiently caustic, yet on being brought into contact with the animal hair 5
develope the required degree of causticity.
The essential characteristic of this feature of this Invention being a solution or
bath of a proper degree of causticity, substantially as indicated in the formula
which I have given, I do not wish to be understood as asserting that the above
described product can be obtained by subjecting to the above described process all 1
coarse animal hair, as, for example, it has been found that pigs' hair is so refractory
as not to yield to the treatment satisfactorily under any modification of the process
as yet practiced. On the other hand it has been found to be applicable to the short
coarse hair of cows, calves, bulls, oxen, and horses.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Ezekiel Luther Hamilton in the Great Seal Patent Office on the
14th April 1880.
EZEKIEL LUTHER HAMILTON, of the City of New York, United States of America,
at present residing at the Golden Cross Hotel, Charing Cross, in the County of
Middlesex. "IMPROVEMENTS IN THE TREATMENT OF SHORT COARSE ANIMAL HAIR."
(A communication from abroad by Gideon Hamilton, of the City of Brooklyn, in
the State of New York, United States of America.)
It is the object of this Invention to obtain froin short coarse animal hair a product
which can be spun or woven, and which possesses in a greater or less degree the
felting properties characteristic of wool or fur, and also possessing in a greater or less
degree the curl and spring suitable for and adapted to upholstering purposes, thus
furnishing a cheap substitute for wools and furs in various manufactures in which
they are used alone or together or mixed with other fibres, and a cheap material
useful for mattresses and other upholstery, thereby extending the economical use of
a fibre to which improved textile felting and other useful properties have been
imparted to many branches of the arts, in which the cost of wools or furs would be
restrictive or prohibitory; and this object is accomplished by subjecting to the novel
process herinafter described, the raw material mentioned, to wit, short coarse
animal hair which in its normal or commercial condition does not possess these
improved properties.
It has been discovered and by a series of experiments demonstrated that the
short coarse hair which forms the coats of certain animals, to wit, the hair of cows,
calves, bulls, oxen, and horses, which either in its ordinary or in its commercial
condition does not possess the characteristics of the finer animal fibres which are
classed as furs or wools, can by a certain chemical treatment have such characteristics
imparted to it to such an extent as to make it amenable to the same treatment as
wools or furs and to render it available for uses similar to those which heretofore
have been peculiar to wools or furs, that is to say, such animal hair by said
treatment is refined and softened, is made lustrous and waved, curled, crimped, or
twisted to a greater or less degree according to the particular purpose for which it
is intended to be used, and rendered capable of being felted, spun, woven, carded,
and formed into bats or wadding. I advisedly define the hair to be thus treated as
short and coarse, because I do not mean to allege that the Invention is applicable to
the long coarse bristle like hair obtained from the manes and tails of horses, or
from the tufts of the tails of cows, calves, bulls, or oxen.
As well as can be determined some of the qualities imparted by this chemical
treatment are derived from a change which takes place in the fibres, and which either
consists of the developement on the exterior of said fibres of serrations or imbrications
like those peculiar to wools or furs, or else imparts to the treated fibre some equivalent
irregularity (not incident to their natural state) which makes them susceptible of
substantially the same felting, spinning, and weaving processes to which wools or
furs are subjected.
In addition to this change in its surface the fibre derives from the process a spiral,
wavy, curly, or twisted form, which may be made more or less positive by a
modification of the treatment according to the purposes for which the product is to
used, for example, the greatest curl being imparted to fibre intended for mattresses
and other upholstering purposes, while a less degree is more conformable with the
requirements of felting, and still less with those of spinning.
The treatment also rids the fibre of its coarse, harsh, stiff, horny, dull, unyielding,
and straight character, and gives it fineness, flexibility, softness, and lustre.

page_text: To obtain the results above set forth the hair is treated with an alkaline solution,
as hereinafter more fully explained. In a suitable vessel I prepare an aqueous
solution of caustic soda or of caustic potash, of a strength measuring about one
tenth of one degree of Beaume's hydrometer; I then take animal hair of the kind
herein before specified, in the condition in which it is found on sale (or if it is unduly
loaded with foreign matters, I previously open it out and wash it with water) and
immerse it in the bath described, and boil it therein for from three to ten minutes,
or in a bath of about one degree Beaumé at a temperature of say, 160° to 170° Fahr.,
the hair would be left from fifteen to twenty minutes.
Considerable variation may be made if found requisite in particular cases in the
strength of the solution, the temperature of the bath, and the time during which the
hair is subjected to the treatment. With a stronger solution a lower temperature
would produce the result within the same time, with a higher temperature the same
strength in the bath would produce the result in less time, and with a weaker
solution or a lower temperature the time must be extended.
These variations cannot be defined more exactly than I have above mentioned,
because they will depend upon the strength of the solution, the maintainance of the
temperature at a uniformn height, or, in some instances, upon the condition of the
hair. The operator can determine whether the process is proceeding properly by
taking from time to time a sample out of the bath and washing it in water slightly
acidulated with sulphuric or other acid, and when this test shows that the fibre has
acquired the proper reduction, fineness, and curl, the mass should be removed at
once from the bath, and plunged into a bath of cold water so as to arrest the action
of the caustic solution, and leave the product of the process in its proper condition;
this washing being continued, with a change of water if necessary, until the solution
is thoroughly washed out. The product is then dried and is ready for use.
Another variation in the process above described will be governed by the use for
which the particular product is designed. For spinning and weaving purposes, or
for forming into bals or wadding, a less curly condition of the product is desirable,
while for mattresses and other upholstering uses more curl and spring are desirable.
To increase the degree of curl it is only necessary to leave the air in the same
solution a little longer, but not to extend the period of immersion in conjunction
with a stronger solution or a higher temperature, as this would tend to deteriorate
the fibre. Where softness, lustre, and pliability are desirable, with only a slight
degree of curl I use the above described process, but with a weaker solution and
at a lower temperature and for a longer time than in the instance specified, that is,
a bath having the strength of, say, one half of one degree of Beaumé's hydrometer,
at about 150° Fahr., and for about forty five to sixty minutes. And if an extreme
degree of softness, lustre, and pliability are desired, I immerse the fibre in a cold
aqueous solution of caustic soda or of caustic potash, of a strength measuring about
five degrees of Beaume's hydrometer, for from twenty four to forty eight hours,
or even longer, or in a cold aqueous solution of caustic soda or of caustic potash,
measuring about ten degrees of Beaume's hydrometer, for from four to six hours, or
even longer; or if the strength of the said cold solution be increased to fifteen
degrees Beaume's hydrometer, the time will be reduced so as not to exceed from
about two to four hours. In all these cases such modifications being observed as
are required by the refractoriness of the fibre, and with due observance of the
energy of the chemical action of the bath as affected by the temperature of the
atmosphere, this action being stimulated by hot weather and retarded by cold.
The formula above given are indicated for the cold treatment in an atmosphere
of from sixty to eighty degrees Falır., and a solution made with soda or potash of
about sixty per centum of causticity.
If desirable the temperature of the solution may be reduced, or raised and main-
tained at a substantially uniform degree, by artificial cold or heat, as for example,
by means of ice or fires

page_text: :—I
As in the hot treatment, so in this cold treatment, the fibre must be watched and
its condition tested froin time to time in acidulated water, and the fibre should be
removed from the solution or caustic bath when the test indicates that it has
attained the proper condition, and should then be thoroughly washed in water.
Instead of using an aqueous solution of caustic soda or of caustic potash, as above
described, I use an aqueous solution of caustic lime in the following manner :-
make a cold saturated solution of caustic lime and bring this solution to a tempera-
ture of about 170° Fahr., and then immerse the hair in it for a period of about three
to four hours; or I bring this solution to a boiling point, then immerse the hair in
it and let it boil for a period of from ten to twenty minutes, testing it from time to
time with acidulated water as above described, and when it has reached the proper
condition I wash it in water as above described.
This Invention further consists in treating the above described product of the
above described process, whether treated in the hot or the cold caustic solution, and
either before or after it has been washed in water, with a further washing in a cold
weak acid solution known as a "sour," or rather in a cold water bath slightly
acidulated with an acid such as sulphuric, muriatic, or acetic, though sulphuric or
muriatic is preferred for this purpose. This acid bath neutralizes any traces of the
caustic soda, or caustic potash, or caustic lime not removed by the water bath,
increases the softness and lustre of the fibre, leaving its curl and spring unimpaired,
and retrieves and preserves the strength of the fibre and prevents deterioration in
it in cases where the action of the first bath has been too energetic. The hair, after
being removed from this acidulated bath or "sour," need not be washed, but is
simply allowed to dry in a warm room or by currents of warm or cold air.
I have specified caustic soda, caustic potash, or caustic lime as the best ingredients
known to ine for the solution forming the first bath in this process, and as imparting
to the bath in the most satisfactory and efficient manner the causticity to which I
mainly attribute the result of the process, but I contemplate using any chemical
equivalents of caustic soda, or of caustic potash, or of caustic lime, as substitutes
therefor, whether such equivalents be simple or compound chemical equivalents;
and I contemplate also using solutions which, although not of themselves sufficiently
caustic, yet on being brought into contact with the animal hair, develope the required
degree of causticity.
The essential characteristic of this feature of this Invention being a solution or
bath of a proper degree of causticity, substantially as indicated in the formulæ
which I have given.
I do not wish to be understood as asserting that the above described product can
be obtained by subjecting to the above described process all coarse animal hair, as,
for example it has been found that pig's hair is so refractory as not to yield to the
treatment satisfactorily under any modification of the process as yet practiced. On
the other hand it has been found to be applicable to the short coarse hair of cows,
calves, bulls, oxen, and horses.
Having thus described the nature and objects of my Invention what I claim
herein as new and desire to secure by Letters Patent is,--
First. The herein before described process of treating the short coarse hair of cows,
calves, bulls, oxen and horses with a solution of caustic soda, or of caustic potash,
or of caustic lime, and washing out such solution, substantially as and for the
purposes described.
Second. The hereinbefore described process of treating short coarse hair of cows,
calves, bulls, oxen, and horses with a solution of caustic soda, or of caustic potash,
or of caustic lime, washing out such solution in water, and then subjecting the
washed fibre to an acidulated bath, substantially as and for the purposes described.
Third. I claim as a new manufacture animal hair possessing the properties
requisite for felting, carding, spinning, or weaving, and for forming into bats or

page_text: wadding, and for mattresses and upholstery, these properties being imparted to the
said raw material by treating it with a solution of caustic soda, or of caustic potash,
or of caustic lime, substantially as herein before described.
In witness whereof, I, the said Ezekiel Luther Hamilton, have hereunto set
my hand and seal, this Tenth day of March, in the year of our Lord One!
thousand eight hundred and eighty.
E. L. HAMILTON. (L.S.)