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Blue Shades On Wool






There are a very large number of blue artificial dyes of every class,
but only a few natural ones, indigo and logwood, and with these every
imaginable tint and shade of blue from the palest sky tints to the
darkest navy blue or blue black can be produced.

While some of the blue colouring matters possess no great powers of
resistance to light, air, washing, etc., the great majority are
remarkable for their fastness to those destructive agencies.

There are but two natural dye-stuffs, indigo and logwood, from which
blue tints can be dyed. With the former, a great variety of shades can
be dyed of a satisfactory character as regards fastness; with the (p. 137)
latter, only dark blues can be dyed, these are fairly fast to milling,
but only moderately so to light.

The artificial blues derived from coal tar are very numerous, and
representatives of all classes, direct, basic, acid and mordant of
dye-stuffs may be found among them. The direct blue dyes do not work
very well on wool. They are apt to dye very red, and somewhat dull
shades, which are, however, fairly fast to washing and light. The
basic blue dyes are fairly numerous, and may be used to dye from pale
sky to deep navy tints. They are apt to work somewhat unevenly on to
wool, owing to their great affinity for the fibre. They give shades
possessing some degree of resistance to light, but which are not very
fast to washing and milling, although, in this respect, there are very
great differences among them. The acid dyeing blues are fairly
numerous, but they dye a great variety of tints, usually fairly fast
to washing, milling and light. The mordant blues are pretty numerous
and of great value for dyeing wool, as they give shades which are
remarkable for their fastness to light, acids and milling, hence they
are most extensively used, especially for dyeing fabrics that are
subject to very hard wear.

#Indigo Dyeing.#--It will be most convenient to begin the description of
the methods of dyeing blues by showing how, and in what manner, indigo
is applied in wool dyeing.

The dyeing of indigo on wool is effected in two ways, either in the
usual way with acid baths, as with acid scarlets, when the so-called
indigo extract is used, or in vats, when indigo itself forms the
dye-stuff.

Indigo is, as all dyers know, or should know, a natural dye-stuff,
prepared from the leaves and twigs of the indigo plant by a species of
fermentation which produces the indigo in a soluble form from the
indigo substance in the plant, followed by oxidation which results in
the separation of the indigo from this solution.

It comes into this country in the form of lumps, which have a dark (p. 138)
blue to bronze blue colour. The dye-stuff is insoluble in water, cold
alcohol, alkalies or weak acids. When heated with strong and fuming
sulphuric acid it dissolves, forming a blue liquor from which the
colouring matter may be obtained on addition of soda in the form of a
paste, which is used in wool and silk dyeing under the name of indigo
extract. But dissolving in sulphuric acid materially affects the
properties of indigo as a dye-stuff, as will be seen later on.

By the action of reducing agents the insoluble blue indigo is
converted into a soluble white indigo. This body is rather unstable,
and on exposure to the air it rapidly becomes oxidised and converted
back again into the blue indigo. Upon this principle is based the
application of indigo in dyeing by means of the vat.

Various methods may be adopted to cause the indigo to become
dissolved. These may be divided into two groups: (1) Fermentation
vats, in which the action of reducing agents is brought about through
the influences of the fermentation of organic bodies, such as woad,
bran, treacle, etc; (2) Chemical vats in which the reducing effect is
brought about by the reaction of various agents on one another.

Of such vats the copperas and lime and the hydrosulphite vats are
examples. The fermentation vats, when in good order, work well and
give good results, but they are most difficult to prepare or set. The
chemical vats are the easiest to work, and (especially the
hydrosulphite vats) are coming to the fore, and are gradually driving
out the fermentation vats.

The actual method of dyeing with the indigo vat is the same with all
methods of preparation. The material to be dyed is well wetted or
wrung out in water. It is then dipped into the vat, handled a few
minutes to ensure its thorough impregnation, then lifted out, the
surplus liquor wrung out, and the material exposed to the air, (p. 139)
when the indigo white on it soon absorbs oxygen and turns into blue
indigo.

With these few preliminary remarks the methods of setting the various
indigo vats will now be described in detail.

#Woad Indigo Vats.#--This is one of the most difficult of the various
methods of setting vats. There are so many opportunities for it to go
wrong, and to be able to set a woad vat successfully will go far to
make a man a successful indigo dyer. No two woad vat dyers use exactly
the same recipe in setting a woad vat, and each considers he has a
secret art by means of which he ensures the successful working of this
vat, and this he jealously guards. All these differences in the manner
of setting the vat are brought about not by any radical differences in
the materials used, but by some unnoticed differences in other
surroundings; differences in the mean temperature of the water used,
in the general conditions of the atmosphere of the indigo shed and in
other similar circumstances, all of which have a material influence on
the development of the vat, but which are, in the majority of cases,
overlooked by the indigo dyer, the result being that a method of
working which is successful in one place would not be so in another.
The fermentation processes depend upon the reducing action brought
about by certain organisms of the nature of the yeast plant which grow
and develop in such vats.

To ensure the proper growth and development of these organisms every
condition must be perfect, correct temperature, proper proportions of
food for them to live on, and a certain degree of alkalinity or
acidity of the vat, and these points are most difficult to regulate as
they will vary very much from time to time.

A successful vat maker is one who closely observes his vats, and the
way in which they are working, and who, as the result of such (p. 140)
observations, is able to tell in what way his vats are deficient,
so that he may know how to supply that deficiency.

The following method of setting a woad vat may be adopted. It is
calculated for 100 gallons of liquor. The vat is filled with hot
water, and 80 lb. of woad are allowed to steep overnight in it, having
first been well stirred into the water, so as to ensure that every
part is wetted out. The next morning there is added 8 lb. madder,
12 lb. bran, 5 lb. quick-lime (previously slaked with water), and
2-1/2 lb. soda. These are thoroughly stirred together, then from 5 to
7-1/2 lb. indigo is stirred in. The indigo should have been previously
ground into a fine paste with water. The temperature of the vat should
now be maintained at from 115 deg. to 125 deg. F. for two to three days,
at the end of which time it ought to be in a state of quiet working.
Should it be found that the fermentation is going on too rapidly, a
little lime may be thrown in, which will retard it. On the other hand,
if it should not be going on with sufficient energy, this may be
remedied by adding a little bran, or better, a little treacle.

When in perfect condition the vat should have a slight smell of
ammonia. If this is not noticed it indicates that the vat is deficient
in alkalinity, and a little more lime should be added. Soda may be
used in the place of lime, but it is so much more energetic in
character that any additions of it have to be made with great care, or
the vat will become too alkaline in character, and the fermentation
will go on too rapidly, the ammoniacal odour is lost, and a peculiar
putrid smell takes its place. As soon as this is noticed, lime ought
to be added to retard the fermentation and to develop the ammoniacal
smell. The colour of a good well-set vat is olive brown.

When all the indigo is dissolved and the colour of the vat is a (p. 141)
clear olive yellow to brown the vat is then ready for dyeing, and
may be used for a long time, until, in fact, the deposit gets too
large and the wool becomes dirtied. But it must not be continually
worked, or it will give bad shades and loose colours. When in a bad
condition it will usually turn of a dark brown colour, and give dull
greenish shades. To remedy this there should be added some bran,
treacle, and a little madder, as well as indigo, and the vat should be
left for a day, at a temperature of 130 deg. F., to get up to full
strength again. Every night when in work indigo ought to be added to
the vat in proportion to that consumed during the day, with bran and
lime, the latter in not too great amount, just sufficient to keep it
of the necessary alkalinity.

#Hydrosulphite Vat.#--This is one of the best vats to use in dyeing with
indigo on wool, or, indeed, on any textile fabric. It is easy to
prepare and cleanly to work. While depending solely on chemical action
for its preparation and use, it is freer from those peculiar defects
to which organic vats, like the woad vats, are liable.

There is a further advantage about this vat, it is not necessary to
prepare each individual vat separately, but a strong mother liquor or
concentrated indigo solution may be prepared, and this only requires
letting down with water to produce a vat of any required strength.

In the preparation of this vat, which was devised by Schutzenberger
and Lalande, bisulphite of soda and zinc dust are used with either
quick-lime or caustic soda. The bisulphite of soda is allowed to act
on the zinc as will be detailed when an acid solution of sodium
hydrosulphite NaHSO{2}, more strictly hydrogen sodium hydrosulphite,
is obtained. The acid solution of hydrosulphite has the property of
rapidly reducing and dissolving indigo, and this solution may be used
in dyeing. To prepare the hydrosulphite a vessel which is fitted (p. 142)
with an agitator and can be closed is filled with zinc, either in the
form of dust, foils, or granules. Then bisulphite of soda of 50 deg. to
60 deg. Tw. strength is poured over the zinc in sufficient quantity to
cover it. All access of air should be avoided as much as possible, as
it leads to oxidation. In the case of using zinc powder the action is
often so rapid as to lead to heating, which also should be avoided.
The operation takes from an hour to two hours, when the liquor may be
drawn off. It must be used immediately to dissolve the indigo; or
otherwise, as it is a very unstable body, it is liable to decompose
and become oxidised, when it loses its solvent properties. If more
hydrosulphite is required, fresh bisulphite may be poured over the
zinc which is left unused in the vessel; if no more is wanted the zinc
which is left should be well rinsed in water and the vessel filled
with water, so as to prevent any oxidation of the zinc, and so keep it
ready for use when required. The liquor thus made will usually have a
specific gravity of 62 deg. Tw. The zinc which is used up in the
preparation of the liquor is replaced by fresh zinc from time to time.

The liquor so obtained is, as stated above, rather unstable, and
contains acid sodium hydrosulphite. By mixing with milk of lime, the
acidity is neutralised, zinc oxide and calcium sulphite are thrown
down, and a solution of neutral sodium hydrosulphite is obtained which
is more stable and can be kept longer without decomposition. To
prepare this, take 10 gallons of the acid liquor, as prepared in the
manner described above, and mix it with 48 lb. of milk of lime, which
is made from 2 lb. good quick-lime. Stir well together, allow all
sediment to settle, or better, filter-press the mass. A liquor of
36 deg. Tw. strength will usually be obtained. Do not let it stand too
long before use, make it alkaline by adding a little lime.

To make the mother or stock indigo, the following method of (p. 143)
procedure may be adopted. Indigo, say 10 lb., is ground into as fine a
paste as possible with 13 lb. milk of lime, of such a strength that 1
gallon shall contain 30 oz. quick-lime. To this is then added so much
of either the acid or the neutral sodium hydrosulphite as can be made
from 90 lb. of bisulphite of soda, the mixture being kept at 150 deg. F.,
until a comparatively clear, greenish yellow solution is obtained,
this will contain about 1 lb. of indigo per gallon.

This mother liquor may be used in setting the vat as follows. The vat
is filled with water which is heated to 120 deg. F., about 200 gallons
being used. To this is then added 1 gallon of either hydrosulphite or
bisulphite of soda to destroy the free oxygen it contains, and prevent
it from oxidising the indigo solution, which is next added. The
quantity of the latter is solely regulated by the depth of shade it is
desired to dye, and as soon as the requisite quantity has been added
the dyeing may be proceeded with at once, and the first portion of
goods put through will soon show the dyer whether too much or too
little of the mother indigo has been added.

Continued use and the consequent agitation of the vat thereby
generated causes it to become oxidised, and the vat acquires a
greenish colour, and does not give fast colours. When this is noticed
the use of the vat is stopped; it is heated to about 160 deg. F., and a
little lime and hydrosulphite added, when all the oxidised indigo in
the vat will speedily be reduced, and the vat put into a workable
condition again. By use this vat tends to become alkaline, and
consequently will spoil the wool, making it harsh and brittle. This is
remedied by adding a little hydrochloric acid.

#Holliday's Patent Indigo Vat.#--Messrs. Read Holliday & Sons have
patented an improved method of making an indigo solution and the
method of using it. They supply the indigo in the form of solution in
two strengths, ordinary and concentrated. Both are used in the same
way, only of the latter less, about one-fourth to one-third, is (p. 144)
required than of the former. For those who would wish to buy their
indigo ready prepared for use these are very convenient forms.

The best way of working the vat for wool is the following: 40 gallons
of water heated to about 50 deg. C., add 1/4 lb. of a mixture of 1-1/4
gallons bisulphite of soda, 52 deg. Tw., and 1 lb. zinc dust, and, say,
1/2 gallon to 2 gallons, of the patent indigo solution, according to
the depth of shade required. The boiled out wool is worked below the
surface of the liquor for about three minutes, then taken out, and the
excess of liquor squeezed back into the vat, the whole operation is
repeated until the shade is arrived at. After dyeing, rinse in an acid
bath of 1 deg. to 2 deg. Tw.

The advantages of this new vat are that brighter shades are obtained
and the darker shades with fewer dips, while the goods are dyed
cleaner and the shades are more quickly obtained, and, we think,
somewhat faster than by the other process.

There is also the advantage that no lime or other alkali is used with
this new indigo vat. The wool should be boiled out before dipping, if
the best results and even shades are desired.

#Potash-Indigo Vat.#--This is also a fermentation vat, and is set in the
following manner: 5 lb. of madder and 4 lb. of bran are mixed with 50
gallons of water and heated for from three to four hours, until a
temperature of from 180 deg. to 212 deg. F. is attained. Then 15 lb. of
carbonate of potash are added and the liquor is allowed to cool down
to about 120 deg. F. Next 10 lb., more or less according to shade
required, of finely ground indigo is added, and the whole is left for
from forty-eight to sixty hours to ferment, being stirred up at
intervals of twelve hours. This vat ferments in much the same way as
the woad vat, and presents the same general appearances. It is not so
liable to get out of order as the woad vat, and in consequence is (p. 145)
much more easily managed. It does not, however, give such bright
shades as either of the vats previously described, but it dyes a
little quicker, and deeper shades can be produced. It is the best vat
to use where indigo dyeing is carried on at irregular intervals, also
for dyeing dark shades of navy blue and for giving an indigo bottom
for dark blues, browns and greens. Such shades stand milling and
alkalies very well.

#Soda-Indigo Vat.#--The soda-indigo vat is set in the following manner:
100 lb. bran is boiled with 200 gallons of water for three hours, then
the liquor is allowed to cool from 100 deg. to 120 deg. F. Then 20 lb.
of soda crystals, 5 lb. slaked lime, and 10 to 15 lb. ground indigo
are added, the mixture being left for two or three days to ferment,
and stirred up at intervals.

Sometimes a little more soda or a little lime is added, as may be
judged from the appearance of the vat, these appearances being
practically the same as those met with in the woad vat, which have
already been described in detail.

The soda vat closely resembles the potash vat, but is cheaper to
produce. It keeps its dyeing power longer, but is somewhat more liable
to get out of order. It is like the potash vat, easier to manage than
the woad vat, as with all the woad vats it is necessary after working
them for a day to replenish them with a little indigo, soda, or
potash, as the case may be, and a little bran.

Cleaner vats are obtained if treacle be substituted for the bran, but
the latter ferments better, and gives better results in working.

#Urine-Indigo Vat.#--This vat has almost, if not quite, gone out of use,
being a rather unpleasant vat to work with, with few advantages over
other vats. One advantage it possesses over the woad and potash vats
is that it is the best for working on a small scale, but the modern
zinc reduction vats run it very close in this respect. The vat is (p. 146)
made as follows: To 50 gallons of stale urine 4 lb. of common salt are
added, and the mixture heated to from 120 deg. F. to 140 deg. F. Then
1 lb. madder and 1 lb. ground indigo are added, and the mass is well
stirred. Then the mixture is allowed to stand until the indigo is
completely reduced, when the vat is ready for dyeing.

#Indigo-Indophenol Vat.#--Messrs. Durand, Huguenin & Co. have introduced
the use of Indophenol along with indigo in wool dyeing. Indophenol can
be reduced in the same way as indigo, and fibres dipped in this
reduced product on exposure to air turn blue in the same way as if
dipped in an indigo vat.

By itself indophenol has not met with much favour from dyers for a
variety of reasons, but it has been found that, mixed with indigo, it
can be used in dyeing with some advantage on the score of cheapness.
The newly mixed vat is made in the following manner:--

In a convenient vessel 26 gallons of water, 15 lb. zinc dust, ground
into a paste with 6 gallons of water, and 7 gallons bisulphite of soda
of 55 deg. Tw. strong are mixed. Then 8 pints caustic soda lye of 72 deg.
Tw., and 16 pints liquor ammonia are added, and the whole mass is well
stirred up; 22 lb. good indigo of about 70 per cent. indigotine and
7-1/4 lb. Indophenol are thoroughly ground into a paste with 7 gallons
of water and 2 pints caustic soda lye of 72 deg. Tw. The paste is added
to the previous mixture, and, after being well stirred in, sufficient
water is added to make the total volume of liquor up to 100 gallons.
The mass is stirred up from time to time during a period of from
thirty-six to forty-eight hours, by which time, as a rule, the indigo
and Indophenol will have been completely reduced, and the vat have
acquired a canary-yellow colour; if it has not, add a little more zinc
dust and bisulphite of soda. It is ready for use when it has a good
yellow colour.

This forms what may be called a mother, or stock vat, from which (p. 147)
the dyeing vat is made in the following manner: Take a sufficient
quantity of water to make the dyeing vat, add some hydrosulphite of
soda (see below) to destroy any oxidising action the vat liquor may
have, then add sufficient of the stock vat to give the required shade,
this point is one which must be determined by experience. The vat is
now quite ready for use, and the wool is entered and treated in the
usual manner.

After dyeing each lot of wool it is advisable to add some of the stock
vat to replace the indigo abstracted by the goods. When a number of
dyeings have been done, it is possible that the vat may become charged
with oxidised indigo and lose its clean, yellow colour. It may be
restored to its former conditions by adding some hydrosulphite of
soda. Of course, after considerable use this, like all other indigo
vats, becomes too highly charged with sediment, etc., to give
excellent results, in which case the only thing that can be done is to
throw the old vat away and start a new one.

The hydrosulphite of soda referred to above is made in the following
way: 4-1/2 lb. zinc dust are ground into a paste with 5-1/2 gallons of
water and then mixed with 4 gallons bisulphite of soda at 55 deg. Tw.,
stirring well so as to keep the temperature down. Then add 3 pints
caustic soda lye of 72 deg. Tw., and 3-1/2 pints liquor ammonia. Finally,
add sufficient water to make 13 gallons. After standing for two or
three days the preparation is ready for use. It should be alkaline in
property; if not, add a little ammonia to make it so. This vat gives
very good bright shades, from sky blue to dark navy, which are equally
as fast as pure indigo shades.

Sometimes woollen goods dyed with indigo rub badly. The causes of this
defect vary from time to time, and in many instances are often obscure
in their origin. All goods intended for indigo dyeing, and more
especially when shades fast to rubbing are desired, should be (p. 148)
thoroughly cleansed, and before passing into the indigo vat should be
thoroughly freed from any soap which may have been used in the boiling
out. Then, after dyeing, they ought to be well rinsed in water and
passed through a sour made with sulphuric acid (2 lb. in 10 gallons),
and then washed again. Vats highly charged with sedimentary matter, or
with zinc or lime, are often the cause of loose shades. The remedy is
obvious, viz., the discarding of such vats and the preparation of
new ones, in fact old vats are perhaps more fruitful sources of loose
shades than any other cause. Soft water suits indigo dyeing better
than hard water, and is to be preferred.

It is not advisable to attempt to get full or deep shades of indigo at
one dip, for such would necessitate the use of strong baths. Dyeings
produced in this way are liable to rub badly, because the indigo lies
mostly on the surface, to which it is more or less mechanically
attached. Light shades of indigo are fast to rubbing, and by repeated
dippings in a light vat or a medium shade vat deep shades of fair
fastness to rubbing can be got.

As repeatedly stated, no indigo vat can be worked continuously with
good results; the continual agitation induced by the passage of the
yarns or cloths into the liquor brings the liquor into contact with
the air, and oxidation sets in, resulting in the indigo being thrown
out of the liquor in its original form. When this happens the vat
loses its original clear yellow or yellowish-brown colour and becomes
greenish, a sure sign that the vat is getting out of condition to give
good results. The remedy has been pointed out in dealing with each
kind of vat, and consists essentially in adding to the vat more of the
active reducing agent and allowing the vat to rest a while.

The dye-vats may be either round tubs or square wooden tanks; for yarn
in hanks, when cloths or warps are being dyed, these may be fitted (p. 149)
with winces and guide rollers so as to draw materials through the liquor.

The hawking machine shown in figure 22 is also very good for indigo
cloth dyeing, and is largely used for this purpose.

[Illustration: Fig. 23.--Indigo Dye-vat.]

Figure 23 also shows an excellent machine for indigo dyeing on cloth.
In this the vat has a frame carrying guide rollers, round which the
cloth passes, so that it travels several times through the vat liquor
in its passage from one end of the vat to the other, the amount of
liquor in the vat being so arranged that the cloth is entirely
immersed the whole time. After going through the liquor the cloth
passes between a pair of squeezing rollers, in order to have any
surplus liquor taken out, then it traverses the space between sets of
guide rollers arranged over the vat, during which time the indigo
becomes oxidised and the blue develops, while finally it is (p. 150)
plaited down on a table. The illustration clearly shows the working of
the machine.

#Dyeing Wool with Indigo Extract.#--Sulphonated indigo, prepared by
dissolving indigo in sulphuric acid, is sold under the name of indigo
extract, or indigo carmine, in two forms--paste (containing,
perhaps, 25 to 30 per cent. actual colour) and powder. Both forms are
freely soluble in water, although some makes are more so than others.
This quality of solubility is dependent upon the proportion of
sulphuric acid which may have been used in the preparation of the
extract. When this is small, what is termed indigo monosulphonic acid
only is formed, which is but slightly soluble in water, and gives red
shades. If a larger proportion of acid be used, then the indigo
disulphonic acid is formed, which is fairly easily soluble in water,
and gives bluer shades than the former.

As all forms of indigo extract are regular articles of commerce,
details for their preparation will not be given here. It will suffice
to say that indigo is heated with strong sulphuric acid until test
samples show that the indigo has been completely dissolved, and it is
then diluted with water and filtered. Sometimes it is sold in this
condition under the term chemic, but if this be used in dyeing wool
it gives rather unsatisfactory results. When sour extract is
required, the liquor filtered out is next treated with salt until all
the colour has been precipitated out, when it is filtered off,
drained, pressed and sold. Should neutral or sweet extract be
required, then the acid liquor is neutralised with soda, and the
product is salted out as before, drained and pressed to a suitable
consistence. It is then sold as indigo extract, or dried, at
150 deg. F., to a powder, which is known as indigo carmine.

All forms of indigo extract are dyed on wool from baths of (p. 151)
Glauber's salt and sulphuric acid, and therefore they can be classed
with the acid-dyeing coal-tar colours. Indigo extract is notable for
its level dyeing and penetrative properties, but it is not fast to
light or milling.

Messrs. Read Holliday & Sons have a powder form of indigo extract
which will be found very useful and to give better shades than the
usual run of paste extract, while it only takes about one-fifth the
quantity to give a similar shade. Working at the boil should be
avoided with indigo extract, as tending to make the shades greenish in
tone; from 170 deg. to 180 deg. F. will usually be found hot enough to
dye good shades.

Indigo extract is not much used by itself in dyeing blues on wool, but
it is extensively employed along with other dye-stuffs to produce an
immense variety of shades--drabs, greens, fawns, greys, lilacs, etc.,
of which some examples will be given later on.

Indigo Blue.--Prepare a bath with 10 lb. indigo extract, 5 lb.
sulphuric acid, and 10 lb. Glauber's salt. Work just under the boil to
shade.

Sky Blue.--The dye-bath contains 1 lb. indigo extract, 2 lb.
sulphuric acid, and 10 lb. Glauber's salt. Work at about 160 deg. F. to
shade.

#Dyeing Wool Blue with Logwood.#--This method of dyeing blue on wool has
lost much of its importance since the introduction of the artificial
dyes, but it is still employed when a blue fast to milling is wanted.
Logwood gives dark navy blue shades. The process is as follows: The
wool is first mordanted by boiling for one and a half hours in a bath
of 3 lb. bichromate of potash and 2-1/2 lb. of tartar. The operation
must be so carried out that the non-oxidising green chrome mordant is
developed on the fibre, and therefore the boiling must be thorough. In
place of tartar, argols and oxalic acid are frequently used, while
lactic acid or lignorosine might be employed. The dyeing is done (p. 152)
in a bath of 20 to 25 lb. logwood, or 5 to 8 lb. logwood extract;
the bath is started cold, heated slowly to the boil, and kept at that
heat for one to one and a half hours. Between the mordanting and
dyeing the wool should be well rinsed.


DYEING BLUE WITH COAL-TAR DYES.

The blue dyes derived from coal tar are very numerous, direct, basic,
acid and mordant blues being known. The direct and basic dyes are very
little used, but the acid and mordant dyes are extensively employed,
as is indicated in the following recipes.

#Dyeing with Direct Dyes.# Pale Blue.--Prepare a dye-bath with 1/2 lb.
Sulphon Cyanine and 10 lb. Glauber's salt. Enter the goods, and work
at the boil for one hour, then lift, wash and dry.

Black Blue.--Prepare a dye-bath with 3 lb. Sulphon Cyanine, 5 lb.
Glauber's salt, and 5 lb. acetate of ammonia; work at the boil for one
hour. Sulphon cyanine works well with other dye-stuffs, and gives
shades which are fast to milling.

#Dyeing with Acid Dyes.# Bright Blue.--Prepare a bath with 2 lb. borax
and 1 lb. Alkali Blue B. Enter the wool at about 170 deg. F., then heat
to the boil, and work for half an hour; then lift, rinse lightly, and
pass into a weak sour bath, with sulphuric acid to raise to the
colour.

Soda may be used in place of borax, but the latter salt maintains the
softness of the wool fibre better.

By using various brands of Alkali Blue (3 R to 7 B), various shades of
blue from a reddish with the 3 R to a pure blue with the 6 B and 7 B
brands may be dyed. The Alkali Blues are fairly fast to light.

Dark Blue.--Prepare a dye-bath with 2 lb. Serge Blue, 10 lb.
Glauber's salt, and 2 lb. sulphuric acid, working at the boil (p. 153)
for one hour. This is a very common way of dyeing blues on serges,
cashmeres and worsted goods. In place of serge blue, what are known as
Blackley blues, or Dewsbury blues, may be employed. These have a
similar composition, but vary a little in the tint of blue they give.

Navy Blue.--Prepare a dye-bath with 2 lb. Induline A, 10 lb.
Glauber's salt, and 2 lb. sulphuric acid, working at the boil for one
hour.

The Indulines are very useful colouring matters for dyeing navy or
dark blues on wool. They have the defect of being liable to give
uneven shades. This may be remedied by omitting the acid when first
making up the bath, entering the wool, working for half an hour to
thoroughly impregnate the material with the dye-liquor, then adding
the acid, and continuing the working for another half-hour. Or the
wool may be treated to a weak chlorine bath before it is dyed, by
first passing it through a weak hydrochloric acid bath and then
through a bath of bleaching powder. By using acetic acid in place of
sulphuric acid more even shades are obtained.

Blue.--Prepare a dye-bath with 1 lb. Acid Blue 1 V, 9 oz. Acid
Violet 1 V, 10 lb. Glauber's salt and 2 lb. sulphuric acid, working at
the boil for one hour.

Blue Black.--For this the dye-bath is made with 8 lb. Acid Blue 1 V,
10 lb. Glauber's salt, and 2 lb. sulphuric acid, working at the boil
for one hour.

Deep Navy Blue.--A very good shade is dyed with 5 lb. Acid Blue 1 V,
3 lb. Acid violet 1 V, 10 lb. Glauber's salt, and 2 lb. sulphuric
acid, working at the boil for one hour.

Deep Navy.--Prepare a dye-bath with 1 lb. Fast acid Magenta B, 3 lb.
Wool Blue B X, 4-3/4 oz. Orange I I, 5 lb. sulphuric acid, and 10 lb.
Glauber's salt, working at the boil for one hour.

The Patent Blues work exceedingly well on wool, giving good bright
shades of a fair degree of fastness. The following recipes will (p. 154)
give some idea of the nature of the shades which may be obtained
from them, while later on their use in combination with other dyes for
the production of compound shades will be shown.

Bright Blue.--Prepare a dye-bath with 2 lb. Patent Blue N, or Patent
Blue superior, 10 lb. Glauber's salt, and 2 lb. sulphuric acid,
working at the boil for one hour.

Bright Greenish Blue.--Use 2 lb. Patent Blue V, 10 lb. Glauber's
salt, and 2 lb. sulphuric acid.

Royal Blue.--Use 2 lb. Patent Blue B, or 2 lb. Patent Blue J (No.
3), 10 lb. Glauber's salt, and 2 lb. sulphuric acid. Patent Blue J
(No. 3) gives slightly more violet shades than Patent Blue N, but
there is not much difference between them.

Saxony Blue.--Use 2 lb. Patent Blue J (No. 00), 2 lb. sulphuric
acid, and 10 lb. Glauber's salt. Patent Blue J (No. 00) dyes shades
very closely resembling those dyed with indigo extract, and where the
latter is used in the dyeing of compound shades the former might be
substituted.

Brilliant Royal Blue.--Prepare a bath with 1-1/2 lb. New Victoria
Blue B, and 10 lb. Glauber's salt. Enter at about 100 deg. F., then
raise to the boil and work for one hour. This gives a very brilliant
shade of blue of a violet tone.

Sky Blue.--Prepare a dye-bath with 1-1/2 oz. New Victoria Blue B and
2 lb. Glauber's salt, working in the manner described in the last
recipe.

Dark Blue.--Prepare a dye-bath with 1-1/2 oz. Acid Violet 5 B, and
1-1/2 lb. Fast Green Bluish, 10 lb. Glauber's salt, and 2 lb.
sulphuric acid, working at the boil to shade; then lift, wash and dry.

Deep Blue.--Make a dye-bath with 4 lb. Chromotrop 6 B, 10 lb.
Glauber's salt, and 4 lb. acetic acid. Work for one hour at the boil;
then lift, add 2 lb. bichromate of potash and 3 lb. acetic acid,
re-enter the goods and work for one hour longer; lift, wash and dry.

The blues produced from the Chromotrops according to the last (p. 155)
recipe are full, solid-looking shades, and have a great degree of
fastness to milling and light. Some other examples showing the
production of blue shades from the Chromotrops will be given later on.

Violet Blue.--Prepare a dye-bath with 2 lb. Victoria Violet 8 B S,
10 lb. Glauber's salt, and 2 lb. sulphuric acid, working at the boil
to shade; then lift, wash and dry.

Deep Blue.--A fine deep blue is dyed on wool from a bath containing
6 lb. Victoria Violet 8 B S, 10 lb. Glauber's salt, and 2 lb.
sulphuric acid, working at the boil to shade.

Deep Sky Blue.--A fine shade is dyed in a bath containing 4 oz.
Cyanole extra, 10 lb. Glauber's salt and 2 lb. acetic acid.

Electric Blue.--Make the dye-bath with 4 oz. Cyanole extra, 1 oz.
Acid Green extra, and 10 lb. bisulphate of soda.

Bright Blue.--A very fine shade of blue can be dyed in a bath
containing 3 lb. Cyanole extra and 10 lb. bisulphate of soda.

Dark Navy Blue.--Prepare the dye-bath with 4 lb. Cyanole extra,
9 oz. Archil Substitute N, and 10 lb. bisulphate of soda.

Dark Navy.--Prepare the dye-bath with 5 lb. Black Blue O, 1-3/4 oz.
Formyl Violet S 4 B, 4 oz. Patent Blue V, 25 lb. Glauber's salt, and
4 lb. bisulphate of soda, adding 1 lb. sulphuric acid when the dyeing
is about half done.

The navy blues given in the last few recipes possess the merit of
considerable resistance to light, air and milling.

Pale Blue.--Make the dye-bath with 1/2 oz. Chromotrop 2 R, 4 oz.
Cyanine B, 7-1/2 oz. Fast Acid Blue R, 1/2 oz. Azo Yellow, 10 lb.
acetic acid, and 15 lb. Glauber's salt.

Peacock Blue.--A fine shade is dyed with 14 oz. Cyanine B, 1-1/2 lb.
Fast Acid Blue R, 2 oz. Azo Yellow, 10 lb. acetic acid, and 15 lb.
Glauber's salt.

Dark Invisible Blue.--Make the dye-bath with 2 lb. Victoria (p. 156)
Black Blue, 10 lb. Glauber's salt, and 3 lb. sulphuric acid.

Bright Blue.--A very fine shade of blue, not, however, fast to
light, is dyed from a bath containing 1/2 lb. Victoria Blue B, and
10 lb. Glauber's salt.

Bright Electric Blue.--Prepare a dye-bath with 3/4 lb. Glacier Blue,
10 lb. Glauber's salt and 3 lb. sulphuric acid, working at the boil.
This gives a very bright green shade of blue.

Dark Peacock Blue.--Make the dye-bath with 1 lb. Naphthol Blue
Black, 10 lb. Glauber's salt, and 3 lb. sulphuric acid.

Peri Wool Blues B & G dye wool in very fast dark blue shades from
baths of Glauber's salt and acetic acid. They are dye-stuffs which
form with copper blue colour lakes of some fastness. The copper is
amalgamated with the dye-stuffs as put on the market.

Pale Navy Blue.--Mordant, 4 lb. bichromate of potash and 1-1/2 lb.
oxalic acid. Dye, 2-1/2 lb. Alizarine Bordeaux B.

Navy Blue.--Mordant, 4 lb. bichromate of potash and 2 lb. oxalic
acid. Dye, 7 lb. Alizarine Bordeaux G.

Bright Violet Blue.--Mordant, 3 lb. fluoride of chrome and 2 lb.
oxalic acid. Dye, 3/4 lb. Celestine Blue B.

Navy Blue.--A reddish shade of navy blue is dyed by mordanting with
3 lb. fluoride of chrome and 2 lb. oxalic acid, and dyeing with 3 lb.
Celestine Blue B and 3/4 lb. Diamond Black.

The Alizarine Cyanines are excellent dye-stuffs for giving dark blue
and navy blue shades on wool. They dye fairly easily, and uniform
shades are readily obtained, while they possess some considerable
penetrative power, so that they are well adapted for dyeing heavy
piece goods. The following recipes show their use and indicate the
character of the shades the various brands yield. It may be added (p. 157)
that the shades are fast to light and milling.

Red Navy Blue.--Mordant, 4 lb. bichromate of potash, 2 lb. tartar,
and 1-1/2 oz. sulphuric acid. Dye, 6 lb. Alizarine Cyanine R R R
double. By using a mordant of 4 lb. fluoride of chrome and 2 lb.
oxalic acid the shade is made brighter and not so red in tone.

Dark Blue.--A red shade of blue almost approaching a navy is
obtained by mordanting with bichromate of potash, as in the last
recipe, and dyeing with 12 lb. Alizarine Cyanine R R, or with 13 lb.
Alizarine Cyanine R. The shade with the latter dye-stuff is scarcely
so red as with the former.

Dark Blue.--Mordant with 4 lb. fluoride of chrome and 2 lb. oxalic
acid and dye with 13 lb. Alizarine Cyanine R.

Dark Blue.--A somewhat brighter and less red shade than is obtained
by working as in the last recipe is given by mordanting with 3 lb.
bichromate of potash, 2 lb. tartar, and 2-1/2 oz. sulphuric acid, and
then dyeing with 17 lb. Alizarine Cyanine G extra.

Dark Blue.--Mordant with 3-1/2 lb. bichromate of potash, 2 lb.
tartar, and 3 oz. sulphuric acid. Dye with 18 lb. Alizarine Cyanine
G G.

Peacock Blue.--Mordant with 4 lb. fluoride of chrome and 2 lb.
oxalic acid. Dye with 18 lb. Alizarine Cyanine G G.

The addition of from 2 lb. to 5 lb. acetate of ammonia in working with
the Alizarine Cyanines is a considerable advantage, by causing the
dye-stuff to penetrate the fibre better and to give more uniform
shades.

Medium Blue.--Mordant with 3 lb. bichromate of potash and 2 lb.
oxalic acid. Dye with 5 lb. Brilliant Alizarine Blue G, and 2 lb.
acetic acid.

Black Blue.--Mordant as in the last. Dye with 20 lb. Brilliant
Alizarine Blue G and 2 lb. acetic acid.

Dark Navy.--Mordant as in the last recipe and dye with 5 lb. (p. 158)
Alizarine Cyanine 3 R double, 5 lb. Alizarine Blue G W, 2 lb.
Brilliant Alizarine Blue G, and 2 lb. acetic acid.

Medium Blue.--Mordant as in the last. Dye with 5 lb. Alizarine Blue
G W, 2-1/2 lb. Brilliant Alizarine Blue G, and 2 lb. acetic acid.

Lavender Blue.--Mordant with 3 lb. bichromate of potash and
2-1/4 lb. tartar. Dye with 2 lb. Alizarine Blue A.

Navy.--Mordant as in the last recipe, and dye with 20 lb. Alizarine
Blue A.

Deep Sky Blue.--Mordant with 3 lb. bichromate of potash and 1 lb.
oxalic acid, then dye with 2-1/2 lb. Chrome Blue.

Bright Blue.--A very fine bright shade is obtained by mordanting as
in the last, and then dyeing with 10 lb. Chrome Blue.

Lilac Blue.--Mordant with 2 lb. bichromate of potash and 1-1/2 lb.
tartar. Dye with 4 lb. Alizarine Blue D N W. Alizarine Blue R gives
somewhat bluer shades than the D N W brand.

Slate Blue.--Mordant with 3 lb. bichromate of potash and 2-1/2 lb.
tartar. Dye with 2-1/2 lb. Alizarine Blue D N W, 4 oz. Alizarine
Brown, and 1-2/3 oz. Alizarine Yellow.

Peacock Blue.--Mordant with 3 lb. bichromate of potash and 2-1/2 lb.
tartar. Dye with 6 lb. Alizarine Blue D N W, 3 lb. Alizarine Yellow,
and 1-1/2 lb. Patent Blue A, adding a little acetic acid to the
dye-bath.

Paris Blue.--Mordant as in the last recipe. Dye with 3 lb. Galleine,
1 lb. Alizarine Blue D N W, and 1 lb. Patent Blue A, adding a little
acetic acid.

Grey Blue.--Mordant as above and dye with 4-1/2 lb. Alizarine Blue
D N W, and 1 lb. Alizarine Brown.

Blue.--Mordant with 10 lb. alum, 3 lb. tartar, and 2 lb. oxalic
acid. Dye with 15 lb. Anthracene Blue W G, 3 lb. acetate of lime, and
1 lb. tannic acid.

Red Navy.--Mordant as in the last recipe and dye with 15 lb. (p. 159)
Anthracene Blue B W, 3 lb. acetate of lime, and 3/4 lb. tannic acid.

Dark Blue.--Mordant with 1 lb. bichromate of potash and 2 lb.
tartar. Then dye with 20 lb. Anthracene Blue W B. Anthracene Blue W G
gives slightly greener shades than the W B brand, while the W R blue
gives redder shades.

Grounding wool with various tints of indigo is a favourite method of
producing many useful shades on wool. In general it is a good plan, as
the bottom so given is a fast and permanent one, and is not in any way
affected (so far as the stability of the colour is concerned) by the
subsequent dyeing operations, care of course being taken that these
are the usual acid or mordanting baths. The only drawback against
bottoming with indigo is the increased cost of dyeing necessitated by
the extra labour, and materials required to dye the bottom. As to the
methods and materials required, they are just those usually employed
in indigo dyeing, and these have been described. The hydrosulphite
vat, or Messrs. Holliday's patent indigo, is, perhaps, the most
convenient method to adopt.

Dark Slate.--Give a medium indigo bottom, then mordant with 3 lb.
fluoride of chrome and 1 lb. oxalic acid, and dye with 1-1/2 lb.
Anthracene Brown W, 1/2 lb. Alizarine Bordeaux G, and 1 oz. Diamond
Flavine.

Dark Navy.--Give a medium indigo bottom in the vat, then mordant
with 3 lb. fluoride of chrome and 1-1/2 lb. tartar, finally dyeing
with 6-1/2 lb. Alizarine Cyanine G, and 1-1/2 lb. Alizarine
Bordeaux G.

Dark Blue.--Give a medium indigo bottom, then mordant with 6 lb.
fluoride of chrome and 2 lb. oxalic acid, finally dyeing with 14 lb.
Alizarine Cyanine Black.

Blue Black.--Give a deep indigo bottom in the vat, then mordant with
3 lb. bichromate of potash and 2 lb. tartar, finally dyeing with (p. 160)
6 lb. Alizarine Cyanine Black and 1-1/2 lb. Alizarine Cyanine 3 R double.





Next: Violet Shades On Wool

Previous: Green Shades On Wool



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