" " A-Naphthylamine
" B-Naphthol with Toluidine.
" " Amidoazobenzene.
" " Orthoamidoazotoluene.
The most important of the naphthol colours is undoubtedly paranitroaniline red, produced by the combination of paranitroaniline and beta-naphthol. In order to produce the best and brightest shades these two bodies must be quite pure.The following directions may be followed:—
Dyeing Paranitroaniline Red on Yarn.
It unfortunately happens that this red does not admit of being worked in large quantities at a time, particularly in the diazo bath where the colour is developed, as the previous operations seem to render the yarn slightly waterproof, and hence if large quantities of yarn were dealt with at one time some would be found to be dyed all right, others would be defective. It has, therefore, been found best to work only about 2 lb. of yarn at a time, carefully carrying out each operation with this quantity. As, however, the process can be quickly worked it follows that in the course of a day a fairly large quantity of yarn can be treated.
1.Grounding.The grounding or preparing bath for 100 lb. of yarn is best made in the following manner: 4 lb. of beta-naphthol are stirred in 2½ lb. of caustic soda liquor 70° Tw., then 1½ quarts of boiling water is added, when dissolved 1½ quarts of cold water. In a separate vessel dissolve 5 lb. Turkey-red oil in 11 quarts of water, then mix the two liquors together and add sufficient water to make up the whole to 12 gallons.
In working sufficient of this liquor is taken and put into a deep tub in which 2 lb. of yarn can be conveniently worked. It is best to work at a tepid heat, say 100° to 110° F.; 2 lb. of the yarn are worked in this liquor, so that it becomes thoroughly impregnated, then it is gently wrung out and hung up. This operation is repeated with each 2 lb. until the whole 100 lb. has been treated, adding from time to time some of the naphthol liquor to make up for that taken up by the cotton. When all the yarn has been through the liquor, give it another dip through the same liquor. Place the yarn in a hydro-extractor for five to seven minutes. Next open out the yarn well, and hang on sticks and dry in a stove at 140° to 150° F. The stove should beheated with iron pipes, through which steam at 30 lb. to 40 lb. pressure passes. This stove should be reserved entirely for this work, for if other goods be dried in it along with the naphthol-prepared cotton, any steam or acid vapours which might be given off from the former might damage the latter.
When thoroughly dry the yarn is ready for the next operation.
2.Developing. The developing bath is made in the following manner: 1½ lb. paranitroaniline is mixed with 1½ gallons of boiling water, and 1¾ quarts of hydrochloric acid at 30° to 32° Tw. Stir well until the paranitroaniline is completely dissolved, add 3½ gallons of cold water, which will cause a precipitation of the hydrochlorate of paranitroaniline as a yellow powder. Let the mixture thoroughly cool off, best by allowing to stand all night; 1¼ lb. of nitrite of soda is dissolved in 4 quarts of cold water, and this solution is added to the paranitroaniline solution slowly and with constant stirring; in about fifteen to twenty minutes the diazotisation will be complete. At this and following stages the temperature of working should be kept as low as possible. Some dyers use ice in preparing their diazo solutions, and certainly the best results are attained thereby, but with paranitroaniline the ice can be dispensed with. After the end of the time sufficient cold water is added to bring the volume of the liquor up to 10 gallons. This diazo liquor will keep for some days, but it decomposes in time, so that it should not be kept too long.
Another liquor is made by dissolving 4 lb. acetate of soda in 11 quarts of water.
The developing bath is made by taking 4 gallons of the diazo liquor and 1 gallon of the acetate liquor and mixing together, and in this bath the prepared yarn, 2 lb. at a time,is worked. The colour develops immediately. The yarn when dyed is lifted out, wrung, and then it is well washed with water, soaped in a bath at 120° F., with a liquor containing ½ oz. soap per gallon, then dried. As the cotton yarn is being passed through the developing bath, the latter is freshened up from time to time by suitable additions of the diazo and acetate liquors in the proportions given above.
Some dyers use a special form of dye vat for dyeing paranitroaniline red on yarn, whose construction can be seen from Fig. 27.
FIG. 27.--Dye-tub for Paranitroaniline Red.FIG. 27.—Dye-tub for Paranitroaniline Red.
The beta-naphthol bath does not keep well and in time tends to grow brown, and when this occurs stains are invariably produced on the cotton. When the yarn or cloth has been prepared with the beta-naphthol, and dried, the developing should be immediately proceeded with, for it is found that by allowing the prepared cotton to lie about it becomes covered with brown stains, and when such stained cotton is passed through the developing bath stains and defective dyeing result.
It has been found that by adding a little tartar emetic to the beta-naphthol bath this is largely if not entirely prevented, and the prepared cloth may be kept for a reasonable length of time before proceeding with the development without fear of stains being formed.
Various additions have been made from time to time to the naphthol bath. Some of these take the form of special preparations of the colour manufacturers, and are sold as naphthol D, naphthol X, red developer C, etc., sometimes gum tragacanth has been added, at others in place of Turkey-red oil there is used a soap made from castor oil with soda and ammonia, but such complicated baths do not yield any better results than the simple preparing liquor given above.
FIG. 28.--Padding Machine for Paranitroaniline Red.FIG. 28.—Padding Machine for Paranitroaniline Red.
Dyeing Paranitroaniline Red on Piece Goods.
The dyeing of this red on to piece goods only differs from that on yarn by reason of the difference in the form of material that is dealt with.
1.Preparing or Grounding.—The same liquor may be used. This operation is best done on a padding machine, a sketch of which is given in Fig. 26, showing the course of the cloth through the liquor. This is contained in the box of the machine, and this is kept full by a constant stream flowing in from a store vat placed beside the machine. After going through the liquor, the cloth passes between a pair of squeezing rollers which squeeze out the surplus liquor. Fig. 28 shows a view of a padding machine adapted for grounding paranitroaniline reds. After the padding, the cloth is dried by being sent over a set of drying cylinders, or through what is known as the hot flue.
2.The Developing.—After being dried, the pieces are sent through a padding machine charged with the developing liquor made as described above, after which the cloth is rinsed, then soaped, and then washed. Some dyers use a continuous machine for these operations, such as shown in Fig. 29.
While the developing bath used for piece goods may be the same as that used for yarns, some dyers prefer to use one made somewhat differently, thus 6¼ lb. paranitroaniline are mixed with 7 gallons boiling-water and 1½ gallons hydrochloric acid; when dissolved 16 gallons of cold water are added, then, after completely cooling, 3½ lb. sodium nitrite dissolved in 3 gallons cold water. After twenty minutes, when the diazotisation is complete, water is added to make the whole up to 40 gallons. The acetate liquor is made from 13¼ lb. acetate of soda in 13½ gallons of water.
Equal quantities of these two liquors are used in making the developing bath.
Of late years, under the names of Azophor red P N, Nitrazol C, Nitrosamine, etc., there has been offered to dyers preparations of diazotised paranitroaniline in the form of a powder or paste, readily soluble in water, that will keep in a
FIG. 29--Developing Machine for Paranitroaniline Red.FIG. 29—Developing Machine for Paranitroaniline Red.
cool and dry place for any reasonable length of time. These are prepared in various ways, and to any dyer who does notwant the trouble of diazotising the paranitroaniline they offer some advantages. They produce a red equal in every respect to that obtained from paranitroaniline. The following details show the method to be followed with some of these products, others are very similar to make the developing baths.
Paranitroaniline Red with Nitrazol C.—Dissolve 25 lb. Nitrazol C in 12 gallons of cold water with constant stirring, then add sufficient cold water to make 37 gallons. In another vessel dissolve 11 lb. of acetate of soda in 5½ gallons water, then add 1½ gallons caustic soda, 36° Tw., mixed with 5½ gallons water. The developing bath is made by mixing both these solutions. It will suffice for both yarn and piece goods.
Paranitroaniline Red with Azophor Red P N.—Dissolve 5½ lb. of Azophor red P N in 4 gallons of water—it dissolves almost completely but usually a few particles of a flocculent character remain undissolved, these can be removed; 2¼ gallons of caustic soda lye of 36° Tw. are diluted with water to 10 gallons, and this is added with constant stirring to the azophor red P N solution. When all is mixed and a clear solution obtained, the developing bath is ready for use, and is used in the same way as the paranitroaniline bath.
Metanitroaniline Orange.—This orange is produced in the same way as the paranitroaniline red, using metanitroaniline or Azophor orange M N in place of the paranitroaniline or the Azophor red P N given for the red. The quantities of all the materials used are identical.
Nitrosamine Red.—Dissolve 5 lb. Nitrosamine red in 5 gallons of water and 2¼ lb. hydrochloric acid, when well mixed there is added 2½ lb. acetate of soda, when all is dissolved add sufficient water to make 6½ gallons. This bath is used exactly in the same way as the paranitroaniline developing bath, and it produces identical results in every way.
Paranitroaniline Brown.—By boiling the paranitroaniline red dyed cotton in a weak bath of copper sulphate a very fine fast brown resembling a cutch brown is produced. A better plan, however, is to prepare the cotton with a ground containing an alkaline solution of copper, 3 lb. beta-naphthol are dissolved in 5 pints of caustic soda lye of 36° Tw., to which is added 5 lb. Turkey-red oil and 10 pints alkaline copper solution, water being added to make 13 gallons of liquor. The cotton is treated in this way as with the ordinary beta-naphthol preparation. The alkaline copper solution is made by taking 5 pints of copper chloride solution at 76° Tw., adding 3¼ lb. tartaric acid, 6 pints caustic soda lye, 70° Tw., and 2 pints of glycerine. The developing bath for the brown is the same as for the paranitroaniline red, or the Azophor red P N bath may be used.
Toluidine Orange.—For this colour the cotton is prepared with the beta-naphthol in the ordinary way. The developing bath is made from 2 lb. orthonitrotoluidine mixed with 12 pints boiling water and 2¼ pints hydrochloric acid; when dissolved allow to cool and then add 12½ lb. ice. When thoroughly cold stir in 2½ pints of sodium nitrite solution containing 3 lb. per gallon. Stir well for twenty minutes, then filter; add 4 lb. sodium acetate and sufficient ice-cold water to make 13 gallons. Use this bath in the same way as the paranitroaniline bath.
Beta-naphthylamine Red.—This red is a good one, but is not so bright or so fast as the paranitroaniline red, hence although somewhat older in point of time it is not dyed to the same extent. The developing bath is made from 1¾ lb. beta-naphthylamine dissolved with the aid of 10 pints boiling water and 1 pint hydrochloric acid. When dissolved allow to cool; add 27 lb. ice and 2 pints hydrochloric acid. When cooled to 32° to 36° Tw., add 3 pints sodium nitrite solution (3 lb. per gallon) and 4 lb. sodium acetate, making up to13 gallons with water. This also is used in precisely the same way as the paranitroaniline red developing liquor.
Alpha-Naphthylamine Claret.—This is a very fine and fairly fast red, and next to the paranitroaniline red may be considered the most important of the naphthol colours. The developing bath is a little more difficult to make, owing to the fact that it is more difficult to get the alpha-naphthylamine into solution. The best way of proceeding is the following: Heat 1¾ lb. of alpha-naphthylamine in 10 pints of boiling water, agitating well until the base is very finely divided in the water, then 1¼ pints of hydrochloric acid is added, and the heat and stirring continued until the base is dissolved, then the mass is allowed to cool, 27 lb. of ice is added and 1½ pints of hydrochloric acid. When cooled down to 32° to 36° F., there is added 3 pints sodium nitrite solution (3 lb. per gallon), and after allowing the diazotisation to be completed, 4 lb. sodium acetate and sufficient water to make 13 gallons of liquor.
The bath is used in the same manner as the previous developing baths.
Dianisidine Blue.—Dianisidine develops with beta-naphthol, a violet blue, which is not very fast, but by the addition of some copper to the developing bath a very fine blue is got which has a fair degree of fastness. The developing bath is made as follows: Mix 10½ oz. dianisidine with 7 oz. hydrochloric acid and 7½ pints of boiling water, when complete solution is obtained it is allowed to cool, then 20 lb. of ice is added. Next 1¾ pints of nitrite of soda solution, containing 1½ lb. per gal. and 2½ pints of cold water. Stir for thirty minutes, then add 1¼ pints copper chloride solution at 72° Tw., and sufficient water to make up 6½ gallons.
The cotton is prepared with beta-naphthol in the usual way, and then passed through this developing bath.
Amidoazotoluol Garnet.—Amidoazotoluol produces with beta-naphthol a fine garnet red in the usual way.
The developing bath is made from 14 oz. amidoazotoluol, mixed with 1½ pints of sodium nitrite solution containing 1½ lb. per gallon, when well mixed add 1 pint of hydrochloric acid diluted with 2 pints water, when this is well mixed add sufficient water to make up a gallon, then add 1 lb. acetate of soda.
The cotton is passed through this dye-bath, then washed well, passed through a weak acid bath, then soaped well, washed and dried.
(8) DYEING COTTON BY IMPREGNATION WITH DYE-STUFF SOLUTION.
Indigo is a dye-stuff which requires special processes for its application to the cotton or wool fibre.
Its peculiarity is that in the form in which it comes to the dyer it is insoluble in water, and to enable it to be dissolved and therefore to be used as a dye, the indigo has to go under a special treatment. The colouring principle of indigo is a body named indigotin, to which the formula C16H16N2O2has been given. When indigo is mixed with substances like lime and copperas, lime and zinc, zinc and bisulphite of soda, which cause the evolution of nascent hydrogen, it takes up this body and passes into another substance which is called indigo white that has the formula C16H12N2O2, leuco, or white indigo; this substance is soluble in water, and so when it is formed the indigo passes into solution and can then be used for dyeing. But indigo white is an unstable substance on exposure to air, the oxygen of the latter attacks the hydrogen which it has taken up, and indigotin is reformed, the indigo white changing again into indigo blue.
Indigo dyeing consists of three operations:—
(1) Preparation of the indigo solution, or, as it is called,
setting the dye vat. (2) Steeping the cotton in this vat. (3)
Exposing to the air.
FIG. 30.--Indigo Dye-vat for Cloth.FIG. 30.—Indigo Dye-vat for Cloth.
There are several methods of preparing, or setting the dye vat, and of each of these modifications are in use in every indigo dye-house:—
(1) With lime and copperas. (2) Zinc and lime vat. (3) Zinc and
bisulphite of soda.
In all cases it is necessary for the indigo to be ground to the form of a fine paste with water; this is usually done in what is known as the ball-grinding mill. The finer it is ground the more easy is it to make the dye-vats.
The dye-vats may be either round tubs or square wooden tanks; when cloths or warps are being dyed these may be fitted with winces and guide rollers, so as to draw the materials through the liquor. In the case of yarns in hanks these appliances are not necessary.
Fig. 30 is a sketch of an indigo dye-vat for cloth or warps.
(1)Lime and Copperas Vat.—To prepare this vat take 75 gallons of water, 4 lb. of indigo, 8 lb. copperas, and 10 lb. of good quicklime. Put these into the vat in the order shown. The amount of indigo is added in proportion to the shade which is required to be dyed: for pale shades, 2 lb. to 3 lb. will be sufficient; while for deep shades, 6 lb. to 7 lb. may be used. The amount of copperas should be from one and a half to twice that of the indigo. The vat should be stirred very well and then left to stand. The changes which occur are probably the following: The lime acts upon the copperas and produces ferrous hydrate—this is unstable and tends to take up oxygen and hydrogen from the water, particularly when there is some indigo present, and forms ferric hydrate; hydrogen is at the same time liberated, and combines with the indigo to form the soluble indigo white. It takes about twenty-four hours to make an indigo vat. When properly made and in good condition, the liquor will be clear and of a brownish-yellow colour, a bluish scum may collect on the surface. If the liquor appears at all greenish it is an indication that the indigo has not been completely reduced, and the vat needs a further addition of lime and copperas, which should be of good quality. Too much of each should not be used, because with them there is formed at the bottom of the vat a sediment of calcium sulphate and ferric hydrate, and it is not wise to increase this to too great an extent, which would be the case if too much lime and copperas were added.
To Use this Vat.—Any scum on the surface is raked on oneside, the cotton yarn immersed for a few minutes, then it is taken out, wrung, allowing the excess liquor to flow back into the vat, and the yarn hung up in the air for the blue to develop. The depth of shade which is dyed depends chiefly upon the amount of indigo in the vat, and also upon the time during which the hanks are dipped in the liquor. Light and medium shades can be readily and conveniently got by a single dip, but deep shades are best got by repeating the dipping once or twice as occasion demands. Deep shades got by using a strong bath at a single dip are found to rub badly, while by repeated dips the dye gets more into the substance of the fibre, and therefore the colour is more firmly fixed and it rubs less.
Some indigo dyers have quite a range of vats, using those fresh made for dyeing deep shades, while the old vats being nearly exhausted are used only for light shades and finally when completely exhausted are thrown away. After the day's work the vat should be stirred up and then allowed to stand. If necessary it may be strengthened by the addition of fresh quantities of indigo, lime and copperas, the next morning it will be ready for use. Generally a lime-copperas vat will remain in good working order for about a month, when it will be necessary to throw it away.
(2) Zinc and Lime Vat.—Zinc dust is a bye-product in the process of zinc extraction. It is a grey, very heavy powder, consisting mostly of finely divided metallic zinc, with traces of oxide and sulphide of zinc. Of these only the metallic zinc is active in reducing the indigo, the rest of the ingredients are not of any consequence. The valuation of zinc dust is a very difficult operation, but it is desirable that this be done, as the product is liable to be very variable in the proportion of actual zinc it contains, and it will pay large buyers always to have it tested. Zinc dust must always be kept in a dry place.
For the reduction of zinc powder lime is chiefly used. The following are two good mixtures.
Vat with zinc and lime:—
10 lb. indigo, dry and ground fine; 5½ lb. zinc dust; 22 lb. slaked lime, dry.
The vat is set as follows, a part of the lime is mixed with the indigo, and the two bodies are well mixed together and allowed to stand for ten minutes, then the zinc powder is added. It is best to make this into a smooth paste with water before adding it to the other ingredients, then the rest of the lime is added and the whole is thoroughly stirred together with the necessary quantity of water.
Vat with zinc powder, lime and soda:—
10 lb. indigo, dry and ground fine; 10 lb. zinc powder; 10 lb. slaked lime, dry; 35 lb. caustic soda at 11° Tw.
Add the lime to the ground indigo, then add the zinc and finally the soda lye.
Soon after the various ingredients of the vats are added together the whole mass becomes hot, when it must be well stirred. It soon begins to evolve gas and the mixture froths. In from two to four hours the evolution of gas ceases. The dark blue solution now becomes yellow and the liquor shows all the characteristics of the indigo vat. It is necessary to keep the vat well stirred up during the time of setting, which takes from five to six hours. If there is much evolution of gas after this time it indicates that too much zinc powder has been added; this is a common fault with dyers, and such excess causes the vat to be too much disturbed and to work dirty. A lime-zinc vat, with occasional additions of newmaterials, keeps good for three months, and even then is in a better condition than the copperas vat.
This vat is used in precisely the same way as the copperas vat; as it contains no sediment, or but little, it works cleaner than the copperas vat and as a rule the indigo blues dyed in it are faster to rubbing.
After a day's work it can be well stirred up and fresh additions of lime, zinc and indigo made to bring it up to its original dyeing strength.
(3) Zinc-Bisulphite Indigo Vat.—When zinc dust and bisulphite of soda are mixed together a reaction sets in, the zinc dissolves, and there is formed sodium hydrosulphite and zinc and sodium sulphites. If now indigo is mixed with this solution the sodium hydrosulphite exerts a reducing action on it, forming white indigo and sodium sulphite, a perfectly clear solution being obtained, which may be used in dyeing cotton or wool.
With this vat it is customary to prepare a strong stock solution of reduced indigo, and to add this to the dyeing vats as may be required.
To Make the Stock Liquor.—Take 20 lb. of indigo, grind into a paste with 20 gallons of boiled water, then add 25 lb. lime slaked into a milk. In a separate tub there is mixed 80 lb. bisulphite of soda, 70° Tw., with 9 lb. zinc dust; this mixture is well stirred and every care taken to prevent it getting hot. When the zinc has dissolved and the mixture is free from any sulphurous smell it is run into the indigo mixture given above. The whole is well stirred together for some time, and then at intervals, until the indigo has become dissolved, sufficient water is added to make up 50 gallons, when the stock liquor will be ready. It should have a deep yellow colour. The surface may have a scum of a bronzy colour collect on it. This stock liquor should be kept in casks free from exposure to the air.
To make the working vat from this stock liquor the following is the method of proceeding:—
Water is run into the vat, and this is heated from 70° to 80° C. in order to expel air from it, after which it may be allowed to cool, then for each 1,000 gallons contained in the vat there is added 30 lb. bisulphite of soda, 3 lb. zinc dust and 3 lb. lime, made into a cream. When all these ingredients are dissolved a quantity of the stock liquor is added in proportion to the shade that it is desired to dye. The whole is well stirred, then the vat is allowed to rest for half an hour to enable any sediment to settle, and then the dyeing is proceeded with.
Should the vat show signs of becoming green in colour it is a good plan to add a mixture of 1 lb. zinc dust and 10 lb. bisulphite of soda. The vat should be kept alkaline, and so a little lime may be added from time to time.
After a day's work it is well to add a little of the zinc and bisulphite mixture, to stir well and allow to stand overnight; the next morning strengthen up the vat by adding fresh stock liquor.
In place of using lime in making up the vat it is possible to use a mixture of caustic soda and ammonia. The lime will tend to cause some sediment to form in the vat, whereas the soda and ammonia will not. When they are used the following mode of working may be followed:—
Stock Liquor.—Soda zinc vat: Put in a tub 26 gallons cold water, 15 lb. zinc powder ground into a paste with 6 gallons water, then stir in 8 gallons bisulphite of soda at 60° Tw., stir well, keeping the heat down as much as possible, after which add 8 pints caustic soda lye at 70° Tw. and 14 pints 20 per cent. liquor ammonia. When all is thoroughly mixed add 30 lb. indigo, ground into a paste with 7 gallons water, allow to stand for half an hour, then add water to make100 gallons, stir at intervals for twelve hours or so, when the stock liquor will be ready for use.
This is used to make the vat in the same way as the first above described. It is needful before adding the stock liquor in making a vat to destroy any oxygen or air which is present in the vat. This may most conveniently be done by adding thereto a solution of hydrosulphite of soda, which may be made by mixing 4½ lb. zinc dust with 5 gallons of water and 3 gallons bisulphite of soda at 70° Tw., stirring well, so that the temperature does not rise too high, there is then added 2 pints caustic soda and 3 pints liquor ammonia, 20 per cent.; when all is dissolved, water is added to make up 13 gallons.
Should the vat show signs of becoming charged with indigo, indicated by its becoming of a green colour, a little of this hydrosulphite added from time to time will correct it.
The hydrosulphite-indigo vat made by either of the two methods indicated above works well, and with due care may be kept in work for months. It gives good shades of indigo, although some dyers consider that these have not the rich bronze hue got from the lime and copperas vat. The shades are rather faster to rubbing.
It has been proposed to employ the dye-stuff indophenol in conjunction with indigo, in which case the method of making the vat is with zinc, bisulphite of soda, caustic soda and ammonia as last described, only in place of using all indigo a mixture of 22 lb. indigo and 7½ lb. indophenol is used. Good blue shades of considerable fastness can thus be got.
Aniline Black.—This black is produced direct upon the cotton fibre by various processes which entail the oxidation of aniline. The chemical composition and constitution of aniline black has not yet been worked out. It is not by any means an easy colour to dye, but still with careful attentionto carrying out the various operations in detail excellent results can be attained.
Aniline black is the fastest black which is known, it resists when well dyed exposure to air and light, is quite fast to washing and soaping. Its disadvantages are that there is, with some methods of working, a tendency to tender the cotton fibre, making it tear easily; secondly, on exposure to air it tends to turn green, this however only happens when the black has not been dyed properly.
At the present day it is perhaps without doubt the most used of all blacks. The methods for producing it are many and varied, the following recipes show how some of the finest aniline blacks can be dyed:—
Ungreenable black is formed when the aniline is by the action of the oxidising agents converted into a substance named nigraniline. This compound when formed will not turn green on the fibre under the influence of acids.
1. The most usual oxidising agent employed for dyeing aniline black is bichromate of soda, which salt will be found much better for all purposes than bichromate of potash. Two separate solutions are prepared: (1) 61 lb. aniline, 9 lb. hydrochloric acid and 10 gallons of water; and (2) 12 lb. bichromate of soda and 20 gallons of water. After cooling, equal quantities of these solutions are mixed and the cotton worked rapidly through the mixture, in a few minutes it assumes a bronze black. The material is then wrung out and steamed for twenty minutes at 3½ lb. pressure, which process renders it jet black and also ungreenable.
2. Another aniline black: For 100 lb. cotton use 11 lb. aniline oil, 15 lb. bichromate of soda, 40 lb. hydrochloric acid and 160 gallons water or 12 lb. sulphuric acid. The dye-bath is filled with the water and the cold solution of aniline oil and a part of the hydrochloric acid in water is first added, afterwards the bichromate is dissolved in a small quantityof water, working cold at first and gradually rising to the boil.
3. Another method is the following and gives a black that is fast and ungreenable and will not rub: 10 lb. chlorate of soda, 10 lb. ammonium chloride, 10 lb. copper sulphate, 35 lb. aniline salt, 101 lb. aniline oil and 20 gallons water. The sodium chlorate and ammonium chloride are dissolved in 6½ gallons and the copper sulphate separately in 5½ gallons water. The aniline salt is dissolved in as little hot water as possible and neutralised with a small amount of aniline oil (10 lb.). The solution of aniline salt is first added to the bath, then the sodium chlorate and ammonium chloride, and lastly the copper sulphate, dilute the whole to 14° Tw. and then enter the goods. Next steam, then run through a solution containing 10 lb. bichromate and 5 lb. soda per 100 gallons water at 160° F., after which the goods are washed and dry steamed at 15 lb. pressure.
4. A very good black is the prussiate or steam aniline black whose cheapness should recommend it. Prepare concentrated solutions of 1¾ lb. aniline salt in 1 gallon water, 1½ lb. ferrocyanide of potash in ¾ gallons water and 1½ lb. potassium chlorate in 1½ gallons water. Mix the solutions and work in a jigger, then steam in a Mather & Platt apparatus for two minutes, then work hot in a jigger in a solution of 2 lb. bichromate per 50 gallons water, dry and finish.
Either of these methods yields a good full black; with a little experience and care perfectly uniform shades will be got.
DYEING UNION (MIXED COTTON AND WOOL) FABRICS.
There is now produced a great variety of textile fabrics of every conceivable texture by combining the two fibres, cotton and wool, in a number of ways; the variety of these fabrics has of late years considerably increased, which increase may be largely ascribed to the introduction of the direct dyeing colouring matters—the Diamine dyes, the Benzo dyes, the Congo and the Zambesi dyes, for in the dyeing of wool-cotton fabrics they have made a revolution. The dyer of union fabrics, that is, fabrics composed of wool and cotton, was formerly put to great straits to obtain uniform shades on the fabrics supplied to him, owing to the difference in the affinity of the two fibres for the dye-stuffs then known. Now the direct dyes afford him a means of easily dyeing a piece of cotton-wool cloth in any colour of a uniform shade, while the production of two coloured effects is much more under his control, and has led to the increased production of figured-dress fabrics, with the ground in one fibre (wool) and colour, and the design in another fibre (cotton) and colour. The number of direct dyes issued by the various colour manufacturers is so great that it would take a fairly considerable space to discuss them all.
To obtain good results it is needful that the dyer of union fabrics should have a thorough knowledge of the dyes he is using, for each dye makes a rule to itself as regards its power of dyeing wool and cotton—some go betteron to the cotton than on to the wool, andvice versa. Some dye wool best at the boil, others equally well below that heat; some go on the cotton at a moderate temperature, others require the dye-bath to be boiling; some will go on to the cotton only, and appear to ignore the wool.
The presence or absence in the dye-bath of such bodies as carbonate of soda, Glauber's salt, etc., has a material influence on the degree of the affinity of the dye-stuff for the two fibres, as will perhaps be noted hereafter. Again, while some of the dyes produce equal colours on both fibres, there are others where the tone is different. With all these peculiarities of the Diamine and other direct dyes the union dyer must make himself familiar. These dyes are used in neutral baths, that is, along with the dye-stuff. It is often convenient to use, along with the direct dyes, some azo or acid dyes, which have the property of dyeing the wool from neutral baths, many examples of such will be found in the practical recipes given below. The dyes now under consideration may be conveniently classed into five groups.
1. Those dyes which dye the cotton and wool from the same bath to the same shade, or nearly so. Among such are Thioflavine S, Diamine fast yellow B, Diamine orange B, Diamine rose B D, Diamine reds 4 B, 5 B, 6 B and 10 B, Diamine fast red F, Diamine Bordeaux B, Diamine brown N, Diamine browns 3 G, B and G, Diamine blues R W, B X, Diamine blue G, Diamine greens G and B, Diamine black H W, Diamine dark blue B, Union blacks B and S, Oxydiamine blacks B, M, D and A, Diamine catechine G, Union blue B B, Oxyphenine, Chloramine yellow, Alkali yellow R, Chromine G, Titan scarlet S, Mimosa, Curcumine, Primuline, Auroline, Congo Corinth B, Thiazole yellow, Columbia yellow, Oxydiamine yellow G G, Oxydiamine oranges G and R, Diamine orange F, Oxydiamine red S.
2. Dyes which dye the cotton a deeper shade than thewool. The following belong to this group: Diamine fast yellow A, Diamine oranges G and D, Diamine catechine G, Diamine catechine B, Diamine sky blue, Diamine blue 2 B, Diamine blue 8 B, Diamine blue B G, Diamine brilliant blue G, Diamine new blue R, Diamine steel blue L, Diamine black R O, Diamine black B 0, Diamine black B H, and Oxydiamine black S O O O, Diamine nitrazol brown G, Diamine sky blue F F, Diamine dark blue B, Diamine Bordeaux B, Diamine violet N, Oxydiamine violet B, Columbia blacks B and F B, Zambesi black B, Congo brown G, Direct yellow G, Direct orange B, Clayton yellow, Cotton yellow, orange T A, Benzo purpurine B, Brilliant Congo R, Chicago blues B and 4 B and 6 B.
3. Dyes which dye wool a deeper shade than the cotton. The dyes in this group are not numerous. They are Diamine gold, Diamine scarlet B, Diamine scarlet 3 B, Diamine Bordeaux S, Diamine blue R W, and Diamine green G, Diamine reds N 0 and B, Chicago blues G and R, Brilliant purpurine R, Diamine scarlet B, Delta purpurine 5 B, Chrysamine, Titan blue, Titan pink, Congo oranges G and R, Erie blue 2 G, Congo R, Brilliant Congo R, Erika B N, Benzo purpurines 4 B and 10 B, Chrysophenine, Titan yellow, Titan browns Y, R and O, Congo brown G, Sulphon azurine B, Zambesi black B.
4. Dyes which produce different shades on the two fibres. Diamine brown G, and Diamine blue 3 R, Diamine brown V, Diamine brown S, Diamine nitrazol brown B, Diamine blues B X and 3 R, Diamine blue black E, Benzo blue black G, Benzo purpurine 10 B, Benzo azurines R, G and 3 G, Columbia red S, Brilliant azurine 5 G, Titan marine blue, Congo Corinths G and B, Azo blue, Hessian violet, Titan blue, Azo mauve, Congo brown, Diamine bronze G, Zambesi browns G and 2 G, Zambesi black F.
5. Azo-acid dyes, which dye wool from neutral baths, and are therefore suitable for shading up the wool to the cotton in union fabric dyeing. Among the dyes thus available may be enumerated: Naphthol blues G and R, Naphthol blue black, Formyl violet 10 B, Lanacyl blue B B, Lanacyl blue R, Alkaline blue, Formyl violets S 4 B and 6 B, Rocceleine, Azo red A, Croceine A Z, Brilliant scarlet, Orange extra, Orange E N Z, Indian yellow G, Indian yellow R, Tropæoline O O, Naphthylamine black 4 B and Naphthol blue black, Brilliant scarlet G, Lanacyl violet B, Brilliant milling green B, Thiocarmine R, Formyl blue B, Naphthylamine blacks D, 4 B and 6 B; Azo-acid yellow, Curcumine extra, Mandarine G, Ponceau 3 R B, Acid violet 6 B, Guinea violet 4 B, Guinea green B, Wool black 6 B.
Regarding the best methods of dyeing, that in neutral baths yields the most satisfactory results in practical working. It is done in a boiling hot or in a slightly boiling bath, with the addition of 6¼ oz. crystallised Glauber's salt per gallon water for the first bath, and when the baths are kept standing 20 per cent. crystallised Glauber's salt, reckoned upon the weight of the goods, for each succeeding lot.
In dyeing unions, the dye-baths must be as concentrated as possible, and must not contain more than from 25 to 30 times as much water as the goods weigh. In this respect it may serve as a guide that concentrated baths are best used when dyeing dark shades, while light shades can be dyed in more diluted baths. The most important factor for producing uniform dyeings is the appropriate regulation of the temperature of the dye-bath. Concerning this, the dyer must bear in mind that the direct colours possess a greater affinity for the cotton if dyed below the boiling point, and only go on the wool when the bath is boiling, especially so the longer and more intensely the goods are boiled.
The following method of dyeing is perhaps the best one: Charge the dye-bath with the requisite dye-stuff and Glauber'ssalt, boil up, shut off the steam, enter the goods and let run for half an hour without steam, then sample. If the shade of both cotton and wool is too light add some more of the dye-stuffs used for both fibres, boil up once more and boil for a quarter to half an hour. If the wool only is too light, or its shade different from that of the cotton, add some more of the dye-stuff used for shading the wool and bring them again to the boil. If, however, the cotton turns out too light, or does not correspond in shade to the wool, add some more of the dye-stuffs used for dyeing the cotton, without, however, raising the temperature. Prolonged boiling is only necessary very rarely, and generally only if the goods to be dyed are difficult to penetrate, or contain qualities of wool which only with difficulty take up the dye-stuff. In such cases, in making up the bath dye-stuffs are to be selected some of which go only on the wool and others which go only on the cotton (those belonging to the second group).
The goods can then be boiled for some time, and perfect penetration and level shades will result. If the wool takes up the dye-stuff easily (as is frequently the case with goods manufactured from shoddy), and are therefore dyed too dark a shade, then dye-stuffs have to be used which principally dye the cotton, and a too high temperature should be avoided. In such cases it is advisable to diminish the affinity of the wool by the addition of one-fifth of the original quantity of Glauber's salt (about 3/8 oz. per gallon water), and from three-quarters to four-fifths of the dye-stuff used for the first lot. Care has to be taken that not much of the dye liquor is lost when taking out the dyed goods, otherwise the quantities of Glauber's salt and dye-stuff will have to be increased proportionately. Wooden vats, such as are generally used for piece dyeing, have proved the most suitable. They are heated with direct, or, still better, with indirect steam. The method which has proved most advantageous is to letthe steam run into a space separated from the vat by a perforated wall, into which space the required dye-stuffs and salt are placed.
The mode of working is rather influenced by the character of the goods, and the following notes will be found useful by the union dyer:—
Very little difficulty will be met with in dyeing such light fabrics as Italians, cashmere, serges and similar thin textiles lightly woven from cotton warp and woollen weft. When deep shades (blacks, dark blues, browns and greens), are being dyed it is not advisable to make up the dye-bath with the whole of the dyes at once. It is much better to add these in quantities of about one-fourth at a time at intervals during the dyeing of the piece. It is found that the affinity of the wool for the dyes at the boil is so much greater than is that of the cotton that it would, if the whole of the dye were used, take up too much of the colour, and then would come up too deep in shade. Never give a strong boil with such fabrics, but keep the bath just under the boil, which results in the wool dyeing much more nearly like to cotton.
Bright Yellow.—Use 2 lb. Thioflavine S in a bath which contains 4 lb. Glauber's salt per 10 gallons of dye liquor.
Good Yellow.—A very fine deep shade is dyed with 2½ lb. Diamine gold and 2½ lb. Diamine fast yellow A, in the same way as the last. Here advantage is taken of the fact that while the Diamine gold dyes the wool better than the cotton, the yellow dyes the cotton the deeper shade, and between the two a uniform shade of yellow is got.
Pale Gold Yellow.—Use a dye liquor containing 4 lb. Glauber's salt in every 10 gallons, 2½ lb. Diamine fast yellow A, 2 oz. Indian yellow G and 3½ oz. Indian yellow R. In this recipe there is used in the two last dyes purely wool yellows, which dye the wool the same tint as the fast yellow A dyes the cotton.
Bright Yellow.—Use in the same way as the last, 2½ lb. Diamine fast yellow B and 3 oz. Indian yellow G.
Gold Orange.—Use as above 2 lb. Diamine orange G, 5½ oz. Indian yellow K and 1½ oz. Orange E N Z.
Deep Orange.—Use 2½ lb. Diamine orange D C, 6½ oz. Orange E N Z, and 3¼ oz. Indian yellow R.
Black.—Use 4½ lb. Union black S, 2 oz. Diamine fast yellow A, 5 oz. Naphthol blue black and 3¼ oz. Formyl violet S 4 B, with 4 lb. Glauber's salt in each 10 gallons dye liquor.
Navy Blue.—Use 1¼ lb. Union black S, 3 lb. Diamine black B H, ½ oz. Naphthol blue black, ½ lb. Formyl violet S 4 B and 2½ oz. alkaline blue B.
Red Plum.—Use a dye-bath containing 2½ lb. Oxydiamine violet B and 3¼ oz. Formyl violet S 4 B.
Dark Green.—A fine shade can be dyed in a bath containing 3 lb. Diamine green B and 1½ lb. Diamine black H W.
Dark Slate.—Use 4 lb. Diamine black H W, 2 oz. Naphthol blue black and 3 oz. Azo red A.
Sage.—Use a dye-bath containing 4 lb. Diamine bronze G and 1¼ oz. Naphthol blue black.
Dark Brown.—A fine dark shade is got from 2½ lb. Diamine brown V and 2 oz. Naphthol blue black.
Peacock Green.—Use 3¾ lb. Diamine steel blue L, 13 oz. Diamine fast yellow B, 14½ oz. Thiocarmine K and 2¼ oz. Indian yellow G in a bath of 4 lb. Glauber's salt per gallon dye liquor.
Dark Sea Green.—Use 9 oz. Diamine steel blue L, 3¾ oz. Diamine fast yellow B, ½ oz. Diamine orange G, 1¼ oz. Naphthol blue black and ¾ oz. Indian yellow G.
Dark Brown.—Use 1 lb. Diamine orange B, 1 lb. Diamine Fast yellow S, 13¾ oz. Union black S, 1 lb. Diamine brown M and ½ lb. Indian yellow G. Fix in an alum bath after dyeing.
Dark Stone.—Use ½ lb. Diamine orange B, 3¾ oz. Unionblack, ¼ oz. Diamine Bordeaux B, 1½ oz. Azo red A and ¾ oz. Naphthol blue black.
Black.—A very fine black can be got from 3½ lb. Oxydiamine black B M, 2 lb. Union black S, 9½ oz. Naphthol blue black and 4 oz. Formyl violet S 4 B.
Dark Grey.—A fine bluish shade of grey is got from 7 oz. Diamine black B H, 2¼ oz. Diamine orange G, 2½ oz. Diamine orange G, 2½ oz. Naphthol blue black and 1 oz. Orange E N Z.
Dark Blue.—A fine shade is got by using 2 lb. Diamine black B H, ½ lb. Diamine black H W, and 3½ oz. Alkaline blue 6 B.
Drab.—Use 3½ oz. Diamine orange B, ¾ oz. Union black, 1/8 oz. Diamine Bordeaux B, ¾ oz. Azo red A and ¼ oz. Naphthol blue black.
Plum.—Use 2½ lb. Diamine violet N, 9½ oz. Union black and 1 lb. Formyl violet S 4 B.
Bright Yellow.—Use a dye-bath containing 4 lb. Thioflavine S, 2 lb. Naphthol yellow S, 10 lb. Glauber's salt and 2 lb. acetic acid.
Pink.—Use 1/6 oz. Diamine Rose B D, ¼ oz. Diamine scarlet B, ½ oz. Rhodamine B and 20 lb. Glauber's salt.
Scarlet.—A fine shade is got from 1½ lb. Diamine scarlet B, ½ oz. Diamine red 5 B and 20 lb. Glauber's salt.
Orange.—Use a dye-bath containing 3½ lb. Diamine orange G, 14½ oz. Tropæoline O O, and 2¾ oz. Orange extra.
Sky Blue.—Use 1½ oz. Diamine sky blue and 1¼ oz. Alkaline blue B.
Bright Blue.—A fine shade similar to that formerly known as royal blue is got by using 1½ lb. Diamine brilliant blue G and 9¼ oz. Alkaline blue 6 B.
Maroon.—Use 3 lb. Diamine Bordeaux B, 2 lb. Diamine violet N and 3¼ oz. Formyl violet S 4 B.
Green.—A fine green similar in shade to that used for billiard-table cloth is got from 2 lb. Diamine fast yellow B, 2lb. Diamine steel blue L, 14½ oz. Thiocarmine R and 7¼ oz. Indian yellow G.
Gold Brown—A fine brown is got from 3 lb. Diamine orange B, ½ lb. Union black, 2½ oz. Diamine brown, ¾ oz. Naphthol blue black and ½ lb. Indian yellow G.
Navy Blue.—Use 3¼ lb. Diamine black B H, 1½ lb. Diamine brilliant blue G and ½ lb. Alkaline blue.
Fawn Drab.—A fine shade is got by dyeing in a bath containing 6¾ oz. Diamine orange B, 1¾ lb. Union black, ¼ oz. Naphthol blue black, ¼ oz. Diamine Bordeaux B and 1 oz. Azo red A.
In all these colours the dye-baths contain Glauber's salt at the rate of 4 lb. per 10 gallons.
Dark Brown.—2½ lb. Diamine orange B, 13 oz. Diamine Bordeaux B, 1½ lb. Diamine fast yellow B, 1¾ lb. Union black and 3½ oz. Naphthol black.
Drab.—1¾ lb. Diamine fast yellow R, 3¼ oz. Diamine Bordeaux B, 2½ oz. Union black, ½ oz. Naphthol blue black and 1¼ oz. Indian yellow G.
Dark Blue.—Use in the dye-bath 4¼ lb. Diamine dark blue B, 1½ lb. Diamine brilliant blue G, ¾ lb. Formyl violet S 4 B and 5 oz. Naphthol blue black.
Blue Black-—Use 3½ lb. Union black S, 1½ lb. Oxydiamine black B M, 6½ oz. Naphthol blue black and ¼ lb. Formyl violet S 4 B.
Dark Walnut.—2¾ lb. Diamine brown M, 1½ lb. Union black S, and 11¼ oz. Indian yellow G.
Peacock Green.—Use in the dye-bath 3 lb. Diamine black H W, 5-1/6 oz. Diamine fast yellow B, 1¼ lb. Thiocarmine R and 1-1/6 oz. Indian yellow G.
Slate Blue.—Use in the dye-bath 6½ oz. Diamine carechine B, 4¾ oz. Diamine orange B, 2½ oz. Union black, 2¾ oz. Orange E N Z, and 1¾ oz. Naphthol blue black.
Dark Sage.—A good shade is dyed with 1 lb. Diamineorange B, 6½ oz. Union black, 1¾ oz. Diamine brown M, 3¼ oz. azo red A and 2¼ oz. Naphthol blue black.
Navy Blue.—Use 2 lb. Diamine dark blue B, 1¼ lb. Lanacyl violet B, and 7 oz. Naphthol blue black.
Bronze Green.—A good shade is dyed with 2 lb. Diamine orange B, 5 oz. Diamine brown N, ¾ lb. Union black S, 1 lb. Indian yellow G and 2½ oz. Naphthol blue black.
Black.—Use 2½ lb. Oxydiamine black B M and 1½> lb. Naphthylamine black 6 B. Another recipe, 2¼ lb. Oxydiamine black B M, 1 lb. Diamine brown M, 1 lb. Orange E N Z and 2 oz. Naphthol blue black.
Dark Brown.—Use 1½ lb. Oxydiamine black B M, 15½ oz. Diamine brown M, 1¾ lb. Indian yellow G and 2¾ oz. Naphthol blue black. Another combination, 1½ lb. Oxydiamine black B M, 1½ lb. Orange E N Z, 1 lb. Indian yellow G and 5 oz. Naphthol blue black.
Scarlet.—3 lb. Benzo purpurine 4 B, ¾ oz. Ponceau 3 R B and ½ lb. Curcumine S.
Crimson.—½ lb. Congo Corinth G, 2 lb. Benzo purpurine 10 B and ½ lb. Curcumine S.
Bright Blue.—2 lb. Chicago blue 6 B, 3 oz. Alkali blue 6 B, 1½ oz. Zambesi blue R X. After dyeing rinse and develop in a bath of 8 oz. sulphuric acid in 10 gallons of water, then rinse well.
Dark Blue.—2½ lb. Columbia fast blue 2 G, 3 oz. Sulphon azurine D, 8 oz. Alkali blue 6 B. After dyeing rinse and develop in a bath of 8 oz. sulphuric acid in 20 gallons of water.
Orange.—9 oz. Congo brown G, 1½ lb. Mikado orange 4 R O and 1½ oz. Mandarine G.
Dark Green.—2 lb. Columbia green, ½ lb. Sulphon azurine D, 1 lb. Zambesi blue B X, 1½ oz. Curcumine S.
Black.—4 lb. Columbia black F B and 2 lb. Wool black 6 B.
Pale Sage Green.—5 oz. Zambesi black D, ¾ lb. Chrysophenine G and 1½ lb. Curcumine S.
Slate.—½ lb. Zambesi black D, ¾ oz. Zambesi blue R X, ½ oz. Mikado orange 4 R 0 and 1½ oz. Acid violet 6 B.
Dark Grey.—1 lb. Columbia black F B, 3 oz. Zambesi black B and ¾ oz. Sulphon azurine D.
Drab.—1½ oz. Zambesi black D, ¾ oz. Mandarine G extra, ¼ oz. Curcumine extra and 3 oz. Mikado orange 4 R O.
Brown.—5 oz. Zambesi black D, ¾ oz. Mandarine G extra, 1½ oz. Orange T A and 2 oz. Mikado orange 4 R 0.
Nut Brown.—¾ lb. Congo brown G, ¼ lb. Chicago blue R W and ¾ lb. Mikado orange 4 R 0.
Dark Brown.—1 lb. Congo brown G, 1½ lb. Benzo purpurine 4 B, 1½ lb. Zambesi black F and ½ lb. Wool black 6 B.
Stone.—1 oz. Zambesi black D, ¼ oz. Mandarine G, ¼ oz. Curcumine extra and 1¼ oz. Mikado orange 4 R 0.
Slate Green.—3 oz. Zambesi black D, 1½ oz. Guinea green B.
Sage Brown.—½ lb. Zambesi black D, 1½ oz. Mandarine G extra, 3 oz. Curcumine extra, 3 oz. Acid violet 6 B, 6 oz. Mikado orange 4 R 0 and 4½ oz. Curcumine S.
Cornflower Blue.—3 oz. Chicago blue 4 R, ¼ lb. Zambesi blue R X, ¼ lb. Acid violet 6 B and ¾ oz. Zambesi brown G.
Dark Brown.—1½ lb. Brilliant orange G, ½ lb. Orange T A, 1 lb. Columbia black F B and ¼ lb. Wool black 6 B.
Dark Blue.—2 lb. Chicago blue W, 1 lb. Zambesi blue R X, ½ lb. Columbia black F B, 10 oz. Guinea green B and ½ lb. Guinea violet 4 B.
The Janus dyes may be used for the dyeing of half wool (union) fabrics. The best plan of working is to prepare a bath with 5 lb. of sulphate of zinc; in this the goods are worked at the boil for five minutes, then there is added the dyes previously dissolved in water, and the working continued for a quarter of an hour; there is then added 20 lb. Glauber's salt, and the working at the boil continued for one hour, at the end of which time the dye-bath will be fairlywell exhausted of colour. The goods are now taken out and put into a fixing-bath of sumac or tannin, in which they are treated for fifteen minutes; to this same bath there is next added tartar emetic and 1 lb. sulphuric acid, and the working continued for a quarter of an hour, then the bath is heated to 160° F., when the goods are lifted, rinsed and dried. In the recipes the quantities of the dyes, sumac or tannin and tartar emetic are given only, the other ingredients and processes are the same in all.
Dark Blue.—2¼ lb. Janus dark blue B and ¼ lb. Janus green B in the dye-bath, and 16 lb. sumac extract and 2 lb. tartar emetic in the fixing-bath.
Blue Black.—3½ lb. Janus black I and ½ lb. Janus black II in the dye-bath, and 16 lb. sumac extract and 2 lb. tartar emetic in the fixing-bath.
Dark Brown.—2½ lb. Janus brown B, 1 lb. Janus black I, 3½ oz. Janus yellow G and 5 oz. Janus red B in the dye-bath, with 16 lb. sumac extract and 2 lb. tartar emetic in the fixing-bath.
Drab.—1½ oz. Janus yellow R, ¾ oz. Janus red B, 1 oz. Janus blue R and ¼ oz. Janus grey B B in the dye-bath, and 4 lb. sumac extract and 1 lb. tartar emetic in the fixing-bath.
Grey.—5 oz. Janus blue R, 3¼ oz. Janus grey B, 1½ oz. Janus yellow R and ¼ oz. Janus red B in the dye-bath, with 4 lb. sumach extract and 1 lb. tartar emetic in the fixing-bath.
Nut Brown.—1 lb. Janus brown R, 8 oz. Janus yellow R and 1½ oz. Janus blue B in the dye-bath, and 8 lb. sumac extract and 1 lb. tartar emetic in the fixing-bath.
Walnut Brown.—3 lb. Janus brown B, 1 lb. Janus red B, 1 lb. Janus yellow R, 1¼ oz. Janus green B in the dye-bath, with 8 lb. sumac extract and 1 lb. tartar emetic in the fixing-bath.
Crimson.—2½ lb. Janus red B and 8 oz. Janus claret red B in the dye-bath, with 8 lb. sumac extract and 1 lb. tartar emetic in the fixing-bath.
Dark Green.—1½ lb. Janus green B, 1½ lb. Janus yellow R and 8 oz. Janus grey B B in the dye-bath, with 12 lb. sumac extract and 1¼ lb. tartar emetic in the fixing-bath.
Chestnut Brown.—1 lb. Janus brown R and 1 lb. Janus yellow R in the dye-bath, and 8 lb. sumac extract and 1 lb. tartar emetic in the fixing-bath.
Before the introduction of the direct dyes the method usually followed, and, indeed still used to a great extent, is that known as cross dyeing. The goods were woven with dyed cotton threads of the required shade, and undyed woollen threads. After weaving and cleansing the woollen part of the fabric was dyed with acid dyes, such as Acid magenta, Scarlet R, Acid yellow, etc. In such methods care has to be taken that the dyes used for dyeing the cotton are such as stand acids, a by no means easy condition to fulfil at one time. Many of the direct dyes are fast to acids and, therefore, lend themselves more or less readily to cross dyeing. For details of the dyes for cotton reference may be made to the sections on dyeing with the direct colours, page 85, etc., while information as to methods of dyeing the wool will be found in the companion volume to this onDyeing of Woollen Fabrics.
Shot Effects.—A pleasing kind of textile fabric which is now made, and is a great favourite for ladies' dress goods, is where the cotton of a mixed fabric is thrown up to form a figured design. It is possible to dye the two fibres in different colours, and so produce a variety of shot effects. These latter are so endless that it is impossible here to enumerate all that may be produced. It will have to suffice to lay down the lines which may be followed to the best advantage, and then give some recipes to illustrate the remarks that have been made. The best plan for the production of shot effects upon union fabrics is to take advantage of the property of certain acid dyes which dye only the wool inan acid bath, and of many of the direct colours which will only dye the cotton in an alkaline bath. The process, working on these lines, becomes as follows: The wool is first dyed in an acid bath with the addition of Glauber's salt and bisulphate of soda, or sulphuric acid, the goods are then washed with water containing a little ammonia to free them from the acid, and afterwards dyed with the direct colour in an alkaline bath.
Fancy or the mode shades are obtained by combining suitable dye-stuffs.
If the cotton is to be dyed in light shades it is advantageous to dye on the liquor at 65° to 80° F., with the addition of 3¼ oz. Glauber's salt, and from 20 to 40 grains borax per gallon water. The addition of an alkali is advisable in order to neutralise any slight quantities of acid which may have remained in the wool, and to prevent the dye-stuff from dyeing the cotton too deep a shade.
Very light shades can also be done on the padding machine. The dye-stuffs of Group II., which have been previously enumerated, do not stain the wool at all, or only very slightly, and are, therefore, the most suitable. Less bright effects can be produced by simply dyeing the goods in one bath. The wool is first dyed at the boil with the respective wool dye-stuff in a neutral bath, the steam is then shut off and the cotton dyed by adding the cotton dye-stuff to the bath, and dyeing without again heating. By passing the goods through cold water to which some sulphuric or acetic acid is added, the brightness of most effects is greatly increased.
Gold and Green.—First bath, 1 lb. Cyanole extra, 7¼ oz. Acid green, 1½ oz. Orange G G, and 10 lb. bisulphate of soda; work at the boil for one hour, then lift and rinse well. Second bath, 4 lb. Diamine orange G and 15 lb. Glauber's salt; work in the cold or at a lukewarm heat. Third bath, at 120° F., 4 oz. Chrysoidine and ¼ oz. Safranine.
Black and Blue.—First bath, 3½ lb. Naphthol black 3 B and 10 lb. bisulphate of soda. Second bath, 2 lb. Diamine sky blue and 13 lb. Glauber's salt. Third bath, 6½ oz. New Methylene blue N. Work as in the last recipe.
Green and Claret.—First bath, 3½ lb. Naphthol red C and 10 lb. bisulphate of soda. Second bath, 2 lb. Diamine sky blue F F, 1¼ lb. Thioflavine S, and 15 lb. Glauber's salt.
Gold Brown and Blue.—First bath, 2½ oz. orange E N Z, 1½ oz. Orange G G, ¼ oz. Cyanole extra and 10 lb. bisulphate of soda. Second bath, 14 oz. Diamine sky blue F F and 15 lb. Glauber's salt.
Dark Brown and Blue.—First bath, ½ lb. Orange G G, 1½ oz. Orange E N Z, 1½ oz. Cyanole extra and 10 lb. bisulphate of soda. Second bath, 12 oz. Diamine sky blue F F and 15 lb. Glauber's salt.
Black and Green Blue.—First bath, 3 lb. Orange G G, 1 lb. Brilliant cochineal 4 R, 1 lb. Fast acid green B N and 10 lb. Glauber's salt. Second bath, 1¾ lb. Diamine sky blue F F, 3¼ lb. Thioflavine S and 15 lb. Glauber's salt.
We may here note that in all the above recipes the second bath (for dying the cotton) should be used cold or at lukewarm heat and as strong as possible. It is not completely exhausted of colour, only about one-half going on the fibre. If kept as a standing bath this feature should be borne in mind, and less dye-stuff used in the dyeing of the second and following lots of goods.
Blue and Gold Yellow.—3 lb. Diamine orange G, 13 oz. Naphthol blue G, 14½ oz. Formyl violet S 4 B and 15 lb. Glauber's salt. Work at just under the boil.
Brown and Blue.—1 lb. Diamine steel blue L, 9½ oz. Diamine sky blue, 1 lb. Orange E N Z, 1 lb. Indian yellow G, 1¾ oz. Naphthol blue black and 15 lb. Glauber s salt. Work at 170° to 180° F.
In these two last recipes only one bath is used, all thedyes being added at once. This is possible if care be taken that dye-stuffs of two kinds are used, one or more which will dye wool and not cotton from neutral baths, and those direct dyes which dye cotton better than wool. The temperature should also be kept below the boil and carefully regulated as the operation proceeds and the results begin to show themselves.
Grey and Orange.—First bath, 3 oz. Orange extra, 1¼ lb. Cyanole extra, 1 lb. Azo red A and 10 lb. bisulphate of soda. Second bath, 5 oz. Diamine orange D C and 3 oz. Diamine fast yellow B.
Green and Red.—First bath, 2 lb. Croceine A Z, and 10 lb. Glauber's salt. Second bath, 1 lb. Diamine sky blue F F, ½ lb. Thioflavine S, and 15 lb. Glauber's salt.
Brown and Violet.—First bath, ¾ lb. Orange extra, ¾ lb. Cyanole extra, and 10 lb. bisulphate of soda. Second bath, 5 oz. Diamine brilliant blue G, and 15 lb. Glauber's salt.
Black and Yellow.—First bath, 7 lb. Naphthol black B, ½ lb. Fast yellow S, and 10 lb. bisulphate of soda. Second bath 3 lb. Diamine fast yellow A, and 15 lb. Glauber's salt.
Black and Pink.—Black as above. Pink with Diamine rose B D (see above).
Green and Buff.—First bath, ¼ lb. Orange extra, ¾ oz. Fast yellow S, and 10 lb. bisulphate of soda. Second bath, ¾ lb. Diamine sky blue F F, ½ lb. Thioflavine S, and 15 lb. Glauber's salt.
Orange and Violet.—First bath, 9 oz. Orange extra, and 10 lb. bisulphate of soda. Second bath, ¾ lb. Diamine violet N, and 10 lb. Glauber's salt.
Black and Blue.—First bath, Naphthol black as given above. Second bath, Diamine sky blue as given above.
Black and Yellow.—Add first 1 lb. Wool black 6 B, and 10 lb. Glauber's salt, then, when the wool has been dyed, add 2 lb. Curcumine S to dye the cotton in the same bath.
Green and Red.—Dye the wool by using 3 lb. Guinea green B, ¼ lb. Curcumeine extra, and 10 lb. Glauber's salt, then add to the bath ¾ lb. Erika B N, and ¾ lb. Congo Corinth G.
Orange and Blue.—Dye the wool first with 1¼ lb. Mandarine G, 2 oz. Wool black 6 B, and 10 lb. Glauber's salt; then the cotton with 2 lb. Columbia blue G.
Blue and Orange.—Dye the wool first with ¾ lb. Guinea violet B, ¾ lb. Guinea green B, and 10 lb. Glauber's salt; then dye the cotton with 2 lb. Mikado orange 4 R O.
Green and Orange.—Dye the wool with 3 lb. Guinea green B, ¼ lb. Curcumeine extra, and 10 lb. Glauber's salt, then dye the cotton in the same bath with 1½ lb. Mikado orange 4 R O.