IMPROVEMENTS IN DYEING, PRINTING, AND OTHER OPERATIONS BASED ON CHEMICAL RE-ACTIONS
Year: 1865

page_text: PROVISIONAL SPECIFICATION left by Richard Archibald Brooman at
the Office of the Commissioners of Patents, with his Petition, on the 4th
December 1865.-A communication from abroad by Mathias Paraf-
Javal, of Thann, France.
I, RICHARD ARCHIBALD BROONAN, of 166, Fleet Street, in the City of
London, Patent Agent, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN DYEING, PRINTING, AND OTHER OPERATIONS BASED ON CHEMICAL
RE-ACTIONS," to be as follows:-
The management of certain precipitates in an isolated state or state of
suspension in liquids is difficult or costly, and certain chemical re-actions are
difficult or incapable of application on account of the instantancousness or the
too great promptitude with which they manifest themselves. This Invention
diminishes or overcomes these inconveniences by fixing these precipitates or
causing them to adhere temporarily or definitely on certain substances by
stopping or moderating these chemical re-actions momentarily.
For example. In order to lose none of the prussiate of potash contained in
a solution it is usually evaporated to crystallization, or if there is too much
water it is precipitated with an iron salt. In the latter case, by reckoning
the time necessary for the prussiate of iron to be deposited, for washing it, for
decomposing it by potash (when it is required to re-convert it into prussiate

page_text: of potash), for then separating by washings this prussiate of potash from the
oxide of iron, it will be seen that the operations are not only long and costly,
but also it is necessary to have receivers of dimensions out of proportion with
the quantity of prussiate. To avoid the inconveniences and the expence I fix
the iron on a substance easily washed, such as pieces of wood, or cotton, or
calico. For instance, if I operate with calico I fix the iron thereon by pre-
ference by one of the means employed by dyers, thus it is sufficient to put
the calico in contact with a solution of nitrate of peroxide of iron (the
concentration of which is not of great importance) of 4° to 10° Twaddle for
example, and then to wash it directly, or to pass it before washing into an
alkaline bath, for example, into a solution of soda crystals of to 5° Twaddle.
The calico thus acquires a pale and dark buff shade, and by putting it in
contact with the solution of prussiate with the acid necessary to the saturation
of the potash added thereto, all the ferrocyanic acid is fixed on the stuff,
which becomes blue. The stuff once charged with Prussian blue is easily
washed by any ordinary machine for washing stuffs; then if I wish to convert
the Prussian blue into prussiate of potash, I treat it by potash dissolved in
the quantity of water strictly necessary to the operation, and wash the stuff
again if required. This new method of operating therefore makes what has
hitherto been a long and costly process short and economic a.
• Another example.-Alkaloids are sometimes obtained from their dilute
solutions by adding tannin, which precipitates them, this tannate of alkaloid
is then washed and is operated on. But in this case the inconveniences
already pointed out in reference to the prussiate are presented and in a greater
degree when the alkaloid possesses value, as the less dense precipitates which
are formed are easily lost in the washing operations. In this case I prepare
the calico (or other substance possessing the required aptitude) by tannin
either alone or associated with bases which form compounds more insoluble
still, and I manipulate the calico thus prepared in a solution of the alkaloid,
which it will entirely absorb, I then operate on the calico as would be done on
the free tannate of alkaloid. Thus I have only to treat it by lime or soda,
which puts the alkaloid at liberty. To prepare the calico in tannin I follow
any of the processes employed by dyers for galling, sumacing, or tanning stuff's
intended for dyeing processes which are well known, but other modes of
fixing the tannin would produce as good results. The advantages of my
method of operating are clear. Further in certain cases it will be advantageous
to leave the tannate of alkaloid on the substance, calico, papers, or others, on
which tannate of alkaloid will have thus been fixed, especially in reference
to medicine of poisonous alkaloids, as those of opium, strychnos, and others.

page_text: Instead of weighing exceedingly small weights, the substance to which 'the
precipitate adheres being much heavier than the precipitate itself, the weighings
may be larger and errors will be much slighter, it is sufficient to know the
quantity of alkaloid fixed on the substance.
Another example.-The violet of aniline with chromates, manganates,
hypermanganates of lead, and others," and other colors generally, oblige the
large amount of accompanying precipitates to be treated. These precipitates
are difficult and costly to treat. I form them upon intermediate substances,
calico for example, whereby all the operations of washing and extracting are
not only very much simplified but less costly, and there are larger products, as
it is not necessary to decant incompletely deposited liquids; besides the colors
are purer, as the precipitate is well retained by the calico or other intermediate
substance.. Further, these precipitates, which are nearly always residues of
little or no value (in the manufacture of aniline violet, for example), are
brought by this Invention to be of great value, as they can serve as dye to the
calicoes on which they have been caused to adhere, and which may be thus
dyed. from the palest to the blackest shades. The value of these dyes is even
such that in the case where I have not the employment of violet, or the
appliance necessary to extract it from the adherent precipitate, I find great
advantages in forming this precipitate on the calico with the sole object of
giving it a color.. The manner of operating is very simple, if the end sought
be to obtain calico dyed black or otherwise, or aniline, violet, or other
analogous color, which should not remain on the calicoes under treatment.
Suppose it is required to make violet with chromate, I impregnate the calico
in a padding machine (machine à foularder) or otherwise with a solution of
chromate (bichromate of potash for example) and of a salt of aniline (hydro-
chlorate for example). By employing these two kinds of salts with equal
equivalents the result is good, and I obtain a calico well dyed, from which I
can extract violet. The difficulty of extracting violet from the free precipitate
renders the employment of great pressure impossible; it has never even been
proposed to treat these precipitates at a greater pressure than that of the air.
But the precipitate fixed on the calico or other substance may be treated
with advantage by water or other liquids. heated above their boiling points.
There are many ways of carrying out this improvement. One of the most
simple, practicable, and economical, consists in treating the calico or other
body on which is the precipitate in vessels similar to those employed in
bleaching at great pressure, or in the extraction at high pressure of dye woods.
In this manner I proceed, as if I wished to treat, the calico as in lye washing,.,

page_text: with this difference, that I take the requisite solution for each operation of
washing, purifying, and extracting. The vessels are of course constructed of
materials which will resist the action of the liquids I employ.
As the prompt action of chromic acid upon aniline is often an inconvenience,
means have been sought in connection with the present Invention of mixing.
these bodies without having too prompt precipitation, and it is found, 1st,
that by diminishing acidity as much as possible, 2nd, by avoiding high
temperatures, 3rd, by increasing the quantities of the solvents, the
formation of the black precipitate is considerably retarded, and in all cases
sufficiently to allow of the calico being put in contact with the bath. It is
especially the lowering of the temperature (which may be in some cases
reduced below that of melting ice) which retards the re-actions. The pre-
cautions to be taken are very simple. To cool sufficiently to. prevent the
re-action and when bodies are found in the baths not soluble enough to cause
these bodies to enter into solution by means of appropriate solvents, such as
alcohol in some cases, or an excess of water in other cases. Thus in a
solution containing only 5 per cent. of bichromate of potash and 4 to 5 per
cent. of hydrochlorate of aniline it is separated immediately from the crystalline
parts (probably chromates of aniline). By replacing in the preparation of a
similar bath a portion, rd for example, by alcohol or other analogous solvent, s
the crystalline parts in question not being separated, remain in solution.
Likewise, by adding much water, sufficient to hold these bodies in solution, it
is evident that they cannot be separated from the baths. If I have used
aniline I can easily regain it by operating on the body, calico for example,
which has been impregnated in the bath. If, on the contrary, I have used ans
excess of water, and this addition of water prevents the calico arriving at the
desired intensity, I repeat the operation (by preference after the re-action of
the first immersion has had time to be made on the fabric, that is to say,
after the precipitate of the first bath has become fixed on the fabric). By
repeating this immersion the required number of times the fabric acquires the s
desired intensity even if the bath is weak. When the aniline bath is not too
acid a temperature of from 47° to 61° Fahrenheit, and even a little higher,
does not always alter the bath immediately, and allows of its being employed
sufficiently concentrated. When the insufficiency of the acid has prevented
the chromic acid producing all the desired action, I employ a simple method
of remedying this inconvenience. After immersion (before, during, or after
drying under heat or cold) I expose the calico to acid vapors (acetic for example),
or 1 even pad it with an acidified liquid, bydrochloric acid for example. An

page_text: addition of sal-ammoniac to the bath is advantageous in many cases; the
refrigerating action of the sal-ammoniac should not be overlooked. Instead
of mixing the chromates with the aniline salts, in some cases it may be more
advantageous to impregnate the body to be dyed first with the chromate
solution, and then after drying or not with the solution of aniline salt, or,
vice versa. And even instead of soluble chromate I can first fix an insoluble
chromate, as those of baryta and lead, and even less soluble, as that of lime ;.
operations easily carried out in the manner ordinarily adopted by dyers.
When I have thus brought the calico to the desired shade and the reaction is
finished I wash it. The black which has never before been produced on calico;
by the action of chromic acid upon aniline is a new black, differing from
ordinary blacks, more fast against acids, and less liable to turn green. Besides
means of dyeing stuffs black from aniline have never before been discovered.
It will be understood that it is not to calico alone that this new process.
applies, but to all substances capable of being dyed. I modify the tone of
this kind of dyeing by submitting the dyed calico to the action of alkaline or
ncid baths, pure or soapy boiling water, or by separating soluble matters
therefrom in water or other vehicles (violet for example), the removal_of_
which will modify the shades. The black with chromates is so superior to
others that I find that another black from aniline acquires new properties by..
causing chromic acid free or combined to re-act upon it.
The proportions of aniline, chromic acid, water, and acid may be very greatly.
varied. I will give several formulæ for this kind of colors.
Formula for a weak bath.-1 lb. of hydrochlorate of aniline, 2 to 3 lbs. of
water, to 3 lbs. of sal-ammoniac. After dissolving, add a solution of to
1 lb, of bichromate of potash in 60 to 80 lbs. of cold water.
After the stuff has been impregnated from this bath, dried, and the anilino
has become oxidated, I pass the stuff (after having washed it, if desired) into
a similar bath, and I repeat this operation until the stuff acquires the required.
intensity. By adding much acid to the bath sufficiently weak it is preserved
some time, less at ordinary temperature, but if it is cooled it is preserved still-
longer and becomes developed on the stuff even before it is dry, and then
the inconveniences of altering the stuff by acid are avoided, as it can be washed.
before drying or before the next immersion.
Formula for less weak baths.-1 lb. of hydrochlorate of aniline dissolved in.
2 lbs. of water. I add to 3 lbs. of sal-ammoniac in powder. After the
dissolving I add to 1 lbs. of bichromate of potash, dissolved in 20 to 30 lbs...
of water.

page_text: It is in a like bath that the substitution of alcohol for 3rd of the water will
be useful, and then the temperature can be much lowered without fear of
separating, useful bodies. An addition of 1 to 10 per cent. of acetic acid
diminishes the preservation of this bath, but it is still capable of being employed
some time; it is sufficient to cool it more in order to increase its durability.
If instead of acetic acid I add one to two pounds of hydrochloric acid the
decomposition of this bath is almost instantaneous unless it be maintained
constantly at a still lower temperature, even below 82° Fahrenheit.
This Invention by impeding or moderating chemical re-actions is not only
applicable to the articles herein-before mentioned, but to many others, for in
this manner I much improve industrial processes based on chemical re-actions.
Thus substances which harden very quickly harden less quickly under the
influence of cold; for example, plaster and water, cements, hydraulic limes
and water, albumen and its analogues, with lime, baryta and others, oxide of
zinc and chloride of zine; and by making use of the new application of cold
before explained I can, for example, employ less water in works with plaster,
cement, and hydraulic lime to retard their setting, and thus obtain the desired
forms much more easily, but also give more density and avoid shrinking and
cracking. The promtitude with which chromates, especially in presence of
acids, act upon thickenings has hitherto prevented their employment in print-
ing on stuffs to discharge and decolorize. By cooling sufficiently I can print
a, mixture thickened with bichromates and acids. There are many other
substances the activity of which is too great and too prompt, and which are
easily worked by cold; thus, for example, I can readily mix hypochlorites
with thickenings when I employ cold; an alkaline solution of reduced indigo,
thickened and intended for printing oxidates with greater difficulty cold than
hot, and so on. Acid, metallic, oxidating, and other preparations affect the
doctors and printing rollers of printing machines less quickly when they are
cooled, There are many ways of fixing a precipitate on a substance intended
to render the washing or treatment of this precipitate more easy; thus it is
with bodies soluble in certain liquids, and which it would be well to treat by
other liquids in which they are insoluble or less soluble. In this case my.
method is very readily employed. If, for example, I wish to purify blues of
aniline insoluble in water but soluble in alcohol, I dissolve these blues in
alcohol and impregnate a suitable substance (cotton fabric, for example). with
this alcoholic. solution; then after evaporation of the alcohol the blue is
found fixed. on the fabric. I next treat this fabric by water, cold, boiling,
alkaline, or otherwise, or by any body which will purify the blue, and when

page_text: the purification is complete I dry the fabric and extract the purified blue
therefrom by alcohol or other suitable solvents. When the bodies which have
to act on the precipitate are energetic, as mineral acids, for example, I choose
substances which are not attacked by these energetic bodies, as the substances
before mentioned (cotton, wood, and others) would be. The number of these
substances is very great; coal, pumicestone, and amianth will answer well.
Each time I have herein-before spoken of dyeing I have for shortness
only mentioned calico, but these improvements in dyeing are applicable to all
bodies capable of being dyed, printed, painted, or otherwise colored, whether
such bodies be cotton or any other substance.
The Invention applies to colorable matters such as aniline, toluidine,
naphthaline, and the like, the colored precipitates of which ordinarily take so
long to treat. Besides the examples herein-before given there are many other
applications too numerous to mention. I may, however, remark that this
Invention embraces every case where one body can be fixed upon another
and become thus more easy to wash or treat, every case where blacks from
aniline are made with the acids of chromium, manganese, and iron upon any
substance fibrous or otherwise of vegetable, animal, or mineral origin, and
every case where the production of chemical re-actions is stopped, moderated,
or impeded by cooling.