Deep Olive Yellow.--Mordant with 3 lb. bichromate of potash and 2 lb. tartar; dye with 20 lb. fustic extract. This gives a very deep shade of olive Yellow.
Bright Lemon Yellow.--Make the dye-bath with 10 lb. Gambine Yellow, 7 lb. alum, and 2 lb. oxalic acid. Enter cold, then slowly heat to the boil and work to shade; then lift, wash and dry.
Leaf Yellow.--Mordant with 3 lb. bichromate of potash and 1/2 lb. sulphuric acid; then dye with 2 lb. Gambine Y and 1 lb. Yellow N.
Deep Leaf Yellow.--A somewhat deeper shade than the last is dyed by first mordanting with 2 lb. bichromate of potash and 1/2 lb. sulphuric acid, then dyeing with 2 lb. Gambine R and 1 lb. Yellow N.
Lemon Yellow.--Prepare a bath with 40 lb. fustic, 6 lb. alum, 6 lb. tartar, and 3/4 lb. tin crystals; enter the wool and work at the boil for one and a half hours, then lift, wash and dry.
Olive Yellow.--Mordant, 3 lb. bichromate of potash and 2 lb. tartar; dye, 3 lb. extract of fustic.
Deep Lemon.--Mordant, 3 lb. bichromate of potash and 2 lb. tartar; dye, 1 lb. Alizarine Yellow G G W.
GoldenYellow.--Mordant, 3 lb. bichromate of potash and 1 lb. sulphuric acid; dye, 10 lb. Alizarine Yellow G G W.
Light Straw.--Make the dye-bath with 3 oz. Anthracene Yellow B N, 5 lb. acetate of ammonia, and 3 lb. bisulphate of soda; work at the boil to shade, then lift, wash and dry.
Old Gold.--A very fine shade of old gold is obtained by dyeing in a bath of 3 lb. Anthracene Yellow C, 5 lb. acetate of ammonia, and 3 lb. bisulphate of soda. Work at the boil for three-quarters of an hour, then lift; add to the dye-bath 3 lb. fluoride of chrome, re-enter the wool, and work for one and a half hours longer at the boil; lift, wash and dry.
Deep Yellow.--Mordant, 3 lb. bichromate of potash and 2-1/2 lb. tartar; dye, 2 lb. Mordant Yellow D.
Pale Olive Yellow.--Dye with 3 lb. Anthracene Yellow G G, 10 lb. Glauber's salt, and 2 lb. acetic acid; after the dye-bath is exhausted of colour add 3 lb. fluoride of chrome, and work at the boil half an hour longer.
Gold Yellow.--Dye with 3 lb. Anthracene Yellow B N, 10 lb. Glauber's salt, and 3 lb. acetic acid; after half an hour's boil, add 1-1/2 lb. bichromate of potash, work for half an hour longer.
Gold Yellow.--Dye with 2 lb. Indian Yellow R, 10 lb. Glauber's salt, and 2 lb. sulphuric acid.
Green Shades on Wool.
Of green shades there is an infinite variety, and these can be dyed in several ways. Either a simple green dye-stuff may be used or mixtures of blue and yellow dye-stuffs may be employed, this latter method being extremely common. It is somewhat interesting to notice that, notwithstanding the great prevalence of green in Nature, the dyer has at his command no natural green dye-stuff, but must, if he prefers to adopt natural dye-stuffs, use a mixture of blue and yellow dye-stuffs to produce green shades. There are but few green colouringmatters derived from coal tar: Gambine, Dinitroso-resorcine, Alizarine Green, Brilliant Green, Malachite Green, Azo Green, Fast Green, Naphthol Green, Acid Green, Diamine Green, Benzo Green almost exhaust the list. Compared with the numerous red and blue dyes which are obtained from coal-tar products, green dyes are conspicuous by their fewness. On the other hand, the dyer has in the blue and yellow dyes from coal tar a means of producing any tint or shade of green he may require.
Members of all the classes of basic, direct, acid, azo and mordant dyes, can be found among the dye-stuffs which can be used in dyeing green, and the methods and principles of their application have been fully described in previous pages. The following recipes contain all the practical information that is needed:--
With Direct Dyes.Dark Green.--The dye-bath is made with 1 lb. Titan Blue 3 B, 1 lb. Titan Yellow Y, 2 lb. salt, and 1/2 lb. acetic acid.
Bright Green.--Prepare a dye-bath with 1 lb. Titan Yellow G, 1 lb. Titan Blue 3 B, 20 lb. salt, and 1/2 lb. acetic acid, working at the boil for one hour.
Dark Green.--Make a dye-bath with 4 lb. Acid Blue 4 S, 2 lb. Titan Yellow Y, and 5 lb. acetate of ammonia, working at the boil to shade.
Blue Green.--Make the dye-bath with 6 lb. Acid Blue 4 S, 2-1/2 lb. Titan Yellow Y, and 5 lb. acetate of ammonia, working at the boil to shade.
Bottle Green.--The dye-bath is made with 5 lb. Acid Blue 4 S, 2-1/2 lb. Titan Yellow Y, and 5 lb. acetate of ammonia, working at the boil to shade. The greens shown in the last three recipes are of a very satisfactory character, and show how, by the use of acetate of ammonia in the dye-bath, the direct dyeing Titan colours can be combined with acid colours.
Green.--Make the dye-bath with 5 lb. Glauber's salt, 5 lb. acetateof ammonia, 2 lb. Sulphon Cyanine, and 1-1/2 lb. Chrysophenine.<7p>
Dark Green.--The dye-bath is made with 2 lb. Sulphon Cyanine, 3/4 lb. Chrysophenine, 5 lb. Glauber's salt, and 5 lb. acetate of ammonia.
Pale Russian Green.--Make the dye-bath with 1/2 lb. Sulphon Cyanine, 2-1/2 oz. Chrysophenine, and 10 lb. Glauber's salt.
The last three shades have the merit of being fast to milling, and fairly so to light.
Olive.--Make a dye-bath with 1 lb. Nyanza Black B, 1 lb. Chrysamine, and 20 lb. Glauber's salt. Work at the boil to shade, lift, wash and dry.
With Acid Dyes.Blue Green.--Make a dye-bath with 10 lb. Glauber's salt, 2 lb. sulphuric acid, 2 lb. Patent Blue N, and 1 lb. Azo Yellow, working at the boil.
Sage Green.--The dye-bath is made with 10 lb. Glauber's salt, 2 lb. sulphuric acid, 2 lb. Azo Yellow, and 1 lb. Patent Blue N, working at the boil.
Olive Green.--Make the dye-bath with 3 lb. Naphthol Green B, 10 lb. Glauber's salt, 15 lb. bisulphate of soda, and 1 lb. copperas, working at the boil to shade.
Bright Green.--Make the dye-bath with 10 lb. Glauber's salt, 5 lb. bisulphate of soda, and 1-1/2 lb. Acid Green B, working at the boil to shade.
Emerald Green.--The dye-bath is made with 1/2 lb. Acid Green B, 10 lb. Glauber's salt, and 2 lb. sulphuric acid. The wool might also be previously mordanted with 15 lb. hyposulphite of soda, and 5 lb. sulphuric acid at the boil for one and a half hours, when it will give a bright shade of emerald green.
Grass Green.--Dye a medium indigo bottom on the wool from the vat, then dye in a bath with 1 lb. Milling Yellow O, 5 lb. Glauber's salt, and 5 lb. bisulphate of soda; lift, wash and dry.
Thelast recipe shows the use of the indigo vat in giving the blue constituent in dyeing greens and other compound colours on wool. This, while being a very effective method of dyeing, yet necessitates two operations which add very materially to the cost of dyeing such shades, hence it is not used for dyeing low class woollen fabrics, but for better class goods it is frequently adopted, fast colours being thus obtained.
In thus using the indigo vat as a bottom dye regard to the properties of indigo must be paid in carrying out any subsequent dyeing operation, so that the indigo on the fibre be not destroyed. As a rule, the indigo will resist any ordinary baths made with Glauber's salt, acetate of ammonia, sulphuric or acetic acids, but it will not resist mordanting operations with bichromate of potash, for the latter salt destroys the indigo. Fluoride of chrome, chrome acetate, or alum, may be used as mordants if necessary.
Pale Sea Green.--The dye-bath contains 1 oz. Cyanine B, 1 oz. Azo Yellow, 5 lb. Glauber's salt, and 1 lb. sulphuric acid.
Moss Green.--The dye-bath is made with 1/2 oz. Chromotrop 2 R, 2 oz. Cyanine B, 4 oz. Fast Acid Blue R, 3-1/4 oz. Azo Yellow, 5 lb. acetic acid, and 10 lb. Glauber's salt.
Deep Moss Green.--Prepare the dye-bath with 4-1/2 oz. Cyanine B, 9 oz. Fast Acid Blue R, 4-1/2 oz. Azo yellow, 1/2 oz. Chromotrop 2 R, 5 lb. acetic acid, and 10 lb. Glauber's salt.
Blue Green.--A very fine shade of blue green is dyed with 9-1/2 oz. Cyanine B, 1-1/4 lb. Fast Acid Blue R, 4 oz. Azo Yellow, 5 lb. acetic acid, and 10 lb. Glauber's salt.
Emerald Green.--A pale, but brilliant shade of green is dyed with 1-1/4 oz. Patent Blue V, 4-1/4 oz. Azo Yellow, 10 lb. Glauber's salt, and 2 lb. sulphuric acid.
Bright Leaf Green.--Dye in a bath with 13 oz. Victoria Yellow,1/2 lb. Patent Blue V, 1/2 oz. Chromotrop 2 R, 10 lb. Glauber's salt, and 2 lb. sulphuric acid.
Deep Leaf Green.--The dye-bath is made with 22 oz. Cyanine B, 1 lb. Azo Yellow, 2-1/2 oz. Chromotrop 2 R, 10 lb. Glauber's salt, and 2 lb. sulphuric acid.
Bright Peacock Green.--The dye-bath is made with 5 oz. Chromotrop 6 B, 4 oz. Patent Blue V, 7 oz. Azo Yellow, 10 lb. Glauber's salt, and 2 lb. sulphuric acid.
Dark Beige Green.--Make the dye-bath with 1/2 lb. Fast Green Bluish, 6 oz. Fast Yellow F Y, 4-1/2 oz. Azo Fuchsine G, 10 lb. Glauber's salt and 2 lb. sulphuric acid.
Invisible Green.--Make the dye-bath with 1-1/2 lb. Fast Green Bluish, 1-1/4 lb. Fast Yellow F Y, 1 lb. Azo Fuchsine G, 10 lb. Glauber's salt and 2 lb. sulphuric acid.
Pale Sage Green.--Make the dye-bath with 1 lb. Azo Acid Brown, 1/2 lb. Fast Acid Violet 10 B, 10 lb. Glauber's salt and 2 lb. sulphuric acid.
Bright Grass Green.--Make a dye-bath with 10 lb. Glauber's salt, 2 lb. sulphuric acid, 3/4 lb. Phenoflavine, 3/4 lb. Azo Carmine B, and 5-3/4 lb. extract of indigo.
Moss Green.--Prepare a dye-bath with 1 lb. Azo Acid Brown, 1/4 lb. Fast Acid Violet 10 B, 10 lb. Glauber's salt and 2 lb. sulphuric acid.
Dark Sage Green.--Make the dye-bath with 3 lb. Azo Acid Brown, 1/2 lb. Fast Acid Violet 10 B, 10 lb. Glauber's salt and 2 lb. sulphuric acid.
Emerald Green.--A fine shade of emerald green can be dyed in a bath which is made from 1/2 lb. Fast Green Bluish, 1 lb. Fast Yellow F Y, 1 lb. Acid Violet 6 B, 10 lb. Glauber's salt and 2 lb. sulphuric acid.
Bottle Green.--Make a dye-bath with 1-1/2 lb. Victoria Violet 8 B S, 3/4 lb. Victoria Yellow, 2 oz. Naphthol Yellow S, 1 oz. Fast Acid Violet R, 1/2 oz. Cyanine B, 10 lb. Glauber's salt and 2 lb. sulphuric acid. Work for one hour at the boil, thenlift; add 3 lb. fluoride of chrome, re-enter the wool, and work for half an hour at the boil.
Pale Pea Green.--A fine bright shade is dyed in a bath containing 1-1/2 oz. Cyanole, 3/4 oz. Naphthol Yellow and 10 lb. bisulphate of soda. By increasing the quantity of dye-stuff in proportion to the material, fine deep shades of green can be dyed.
Deep Electric Green.--Make the dye-bath with 2 lb. Cyanole, 1 lb. Indian Yellow G and 10 lb. bisulphate of soda, working at the boil for one hour; then lift, wash and dry.
With Mordant Dyes.Green.--Mordant with 10 lb. alum, 1 lb. bichromate of potash and 16 lb. tartar. Dye with 10 lb. indigo extract, 2 lb. fustic extract and 3 lb. alum, working at the boil; lift, wash and dry.
Dark Green.--Mordant with 3 lb. bichromate of potash, 8 lb. alum and 3 lb. tartar. Dye with 10 lb. extract of indigo, 2 lb. extract of fustic and 3 lb. alum, working at the boil.
Sea Green.--Mordant with 3 lb. bichromate of potash and 2-1/2 lb. tartar at the boil for one and a half hours. Dye with 1-1/4 lb. Alizarine Blue D N W, 3-3/4 lb. Alizarine Yellow and 5 oz. Alizarine Brown, at the boil for two hours.
Bronze Green.--Make a dye-bath with 2 lb. Cyanole extra, 2 lb. Tropeoline O, 1 lb. Archil Substitute N and 10 lb. bisulphate of soda, working at the boil to shade.
Green.--A very fine shade of green is dyed as follows: Mordant with 3 lb. bichromate of potash and 2-1/2 lb. tartar. Dye with 4 lb. Alizarine Blue D N W, 1-1/2 lb. Patent Blue A and 2-3/4 lb. Alizarine Yellow.
Blue Green.--Mordant as in the last recipe. Dye with 6 lb. Alizarine Blue D N W, 1-1/2 lb. Patent Blue A, and 1-1/4 lb. Alizarine Yellow G G W.
Bright Pale Sage Green.--Mordant with 3 lb. bichromate of potash and 2 lb. sulphuric acid. Dye with 5 lb. Alizarine YellowG G W, 3/4 lb. Alizarine Brown and 1-1/4 lb. Alizarine Blue D N W.
Deep Sage Green.--Mordant with 3 lb. bichromate of potash and 2-1/2 lb. tartar. Dye with 4 lb. Alizarine Yellow G G W, 3-1/4 lb. Anthracene Brown and 2-1/4 lb. Alizarine Blue D N W.
Pale Sea Green.--Mordant with 2 lb. bichromate of potash and 1-1/2 lb. tartar. Dye with 1 lb. Coeruleine B.
Bottle Green.--Mordant with 3 lb. bichromate of potash and 2-1/2 lb. tartar. Dye with 20 lb. Coeruleine S W.
Slate Green.--Mordant with 2 lb. bichromate of potash and 1-1/2 lb. tartar. Dye with 3 lb. Alizarine Green S.
Invisible Green.--Mordant with 3 lb. bichromate of potash and 2-1/2 lb. tartar. Dye with 17-1/2 lb. Alizarine Green S.
Peacock Green.--Mordant with 3 lb. bichromate of potash and 2-1/2 lb. tartar. Dye with 8 lb. Alizarine Green S.
Dark Bottle Green.--Mordant with 4 lb. bichromate of potash and 3 lb. tartar. Dye with 15 lb. Anthracene Blue W G, and 1-1/2 lb. Mordant Yellow.
Invisible Green.--Mordant with 3-1/2 lb. bichromate of potash and 2-1/2 lb. tartar, working at the boil for one and a half hours. Dye with 20 lb. Alizarine Green S W, and 1 lb. acetic acid.
Sage Green.--Give a medium indigo ground to the wool in a vat, then dye for one hour at the boil in a vat containing 1/2 lb. Anthracite Black B, 2 lb. Anthracene Yellow C, 2 oz. Diamine Fast Red F, and 5 lb. acetate of ammonia; then lift, add 3 lb. fluoride of chrome, re-enter into the dye-bath and work half an hour longer at the boil; lift, wash and dry.
Peacock Green.--Give a medium indigo bottom on the vat, then dye for one hour at the boil in a dye-bath made with 1/2 lb. Anthracene Yellow C, 2 oz. Diamine Fast Red F, and 5 lb. acetic acid; then lift, add 3 lb. fluoride of chrome, work for half an hour longer at the boil, then lift, wash and dry.
Bottle Green.--Mordant by boiling in a bath of 3 lb. copperasand 1 lb. oxalic acid. Dye in a bath with 15 lb. Gambine R.
Light Green.--Mordant with 3 lb. copperas and 1 lb. oxalic acid. Dye with 2-1/2 lb. Gambine Y.
Medium Green.--Mordant as in the last dye with 10 lb. Gambine Y.
Deep Grass Green.--Mordant with 3 lb. bichromate of potash and 2-1/2 lb. tartar. Dye with 9 lb. Coerulein and 1-3/4 lb. Galloflavine.
Bright Grass Green.--Mordant with 4 lb. copperas and 1 lb. oxalic acid. Dye with 5 lb. Gambine Y, 1/2 lb. Yellow N, and 2 lb. bisulphate of soda.
Shades dyed with Gambine are very fast to milling and light.
Pale Sage Green.--Mordant with 3 lb. bichromate of potash and 1 lb. tartar. Dye with 1/2 lb. Milling Yellow O, 2 lb. Alizarine Black S W, and 2 lb. acetic acid.
Medium Green.--Mordant with 2-1/2 lb. bichromate of potash and 1-1/2 lb. oxalic acid. Dye with 1-1/2 lb. Diamond Yellow B, 3-1/2 lb. Brilliant Alizarine Blue G, and 1 lb. acetic acid.
Invisible Bronze Green.--Give a medium bottom on the indigo vat and then mordant with 3 lb. fluoride of chrome and 2 lb. tartar. Finally dye with 3 lb. Alizarine Bordeaux S, and 4 lb. Diamond Flavine, working at the boil for two hours.
Pale Slate Green.--Mordant with 3 lb. bichromate of potash and 2-1/2 lb. tartar, and then dye with 1 lb. Alizarine Blue D N W, Alizarine Yellow and 5 oz. Alizarine Brown.
Light Green.--Mordant in the usual way with 2-1/2 lb. bichromate of potash and 2 lb. tartar. Dye with 1 lb. Methylene Blue and 1 lb. fustic extract, working at the boil.
Fast Green.--Mordant with 8 lb. alum, 2 lb. bichromate of potash, 2 lb. sulphuric acid and 3/4 lb. tin salt. Dye with 20lb. indigo extract and 10 oz. fustic extract, working at the boil for one and a half hours.
Bottle Green.--Mordant with 3 lb. bichromate of potash and 2-1/2 lb. tartar. Dye with 4 lb. extract of fustic, 1 lb. extract of logwood, and 2 oz. Anthracene Red. Work for one and a half hours, then add 3/4 lb. copperas, and work for half an hour longer.
Dark Green.--Mordant with 3 lb. bichromate of potash and 2-1/2 lb. tartar. Dye with 1-1/2 lb. Methylene Blue, 1-1/2 lb. extract of logwood, and 4 lb. extract of fustic, working at the boil for two hours.
Olive.--Prepare a dye-bath with 1-1/2 lb. Yellow N, 1/4 lb. Archil Substitute, 4 lb. extract of indigo, 10 lb. Glauber's salt, 2 lb. sulphuric acid, and 2 lb. alum, working at the boil to shade.
Bright Green.--Prepare a dye-bath containing 8 oz. Acid Green Extra and 10 per cent. bisulphate of soda. Enter at 130° F., raise to the boil, boil for three-quarters of an hour, and rinse.
Bluish Green.--Prepare a dye-bath containing 8 oz. Fast Acid Green B N and 10 lb. bisulphate of soda. Enter at 130° F., raise to the boil, boil for three-quarters of an hour, and rinse.
Bluish Green.--Prepare a dye-bath containing 8 oz. Cyanole Green 6 G and 10 lb. bisulphate of soda. Enter at 130° F., raise to the boil, boil for three-quarters of an hour, and rinse.
Turquoise Green.--Prepare a dye-bath containing 8 oz. Cyanole Green B and 10 lb. bisulphate of soda. Enter at 130° F., raise to the boil, boil for three-quarters of an hour, and rinse.
SlateGreen.--Mordant the wool by boiling for one and a half hours in a bath containing 3 lb. bichromate of potash, 1-1/4 lb. Copper sulphate and 2-1/4 lb. tartar; then rinse well, and dye in a bath containing 2-1/2 lb. Logwood Extract (dry), 1-1/4 lb. Fustic Extract (dry), and 3 lb. Sumac. Enter the goods in a warm bath, work for half an hour, then raise to the boil and work for three-quarters of an hour; lift, and sadden by adding 6 oz. Copperas. After re-entering the goods, work to shade.
Olive.--Boil two hours in a bath consisting of 1-1/2 lb. tin salt, 2-1/2 lb. bichromate of potash, 10 lb. alum and 2-1/2 lb. sulphuric acid. Then enter in a boiling dye-bath containing 1-1/2 lb. alum, 4 lb. fustic extract and 3-1/2 lb. indigo extract.
Fulling Fast Olive.--For one hour upon a bath containing 50 lb. Fustic, 5 lb. Bluestone, 2 lb. Tartar, 4 lb. Sumac, 1 lb. Copperas; lift and wash.
Fast Bright Olive.--Boil for one hour upon a bath of 50 lb. Fustic, 3 lb. Bluestone, 2 lb. tartar, 1 lb. copperas, 2 oz. indigo extract.
Yellow Olive.--Prepare a bath containing 10 lb. Glauber's salt, 1-1/2 lb. Anthracene Yellow B N, 2 lb. extract of indigo, 3 oz. Orange E N Z, 4 lb. sulphuric acid. Enter yarn at 160° F., give three turns, raise the temperature slowly to the boil, turn to shade; lift, and wash.
Olive Green.--Mordant with 2 lb. potash bichromate, 1-1/2 lb. sulphate of copper, 1/2 lb. sulphuric acid. Boil for an hour and a half. Dye in a bath with 8 lb. Fustic extract, 5 lb. Sumac, 5 lb. Logwood, at the boil for an hour and a half.
Olive Bronze.--Make the dye-bath with 10 oz. Fast Yellow S, 5 lb. Indigo extract, 5 oz. Orange E N Z, 4 lb. sulphuric acid, 10 lb. Glauber's salt. Enter yarn at 140° F., work for a few minutes, then bring slowly to the boil and work to shade.
Emerald Green.--Prepare the dye-bath with 1 lb. Acid GreenB N, 2 oz. Naphthol Yellow S, 10 lb. Glauber's salt, 2 lb. sulphuric acid. Enter cold, then raise to the boil and work for a quarter of an hour; wash and dry.
Invisible Green.--First mordant the wool in a bath containing 3 lb. bichromate of potash, 1-1/2 lb. copper sulphate, 1 lb. sulphuric acid. Work at the boil for one and a half hours, then dye in a fresh bath containing 2 lb. Milling Yellow O, 2 lb. Logwood extract, 20 lb. Glauber's salt. Work at the boil for one and a half hours, then lift, wash and dry.
Sea Green.--Prepare a dye-bath with 5 lb. Glauber's salt, 2 lb. sulphuric acid, 2 lb. indigo extract, 1/2 per cent. Acid Green blue shade. Dye as usual.
Cyprus Green B, and Cyprus Blue B, belong to a new group of dyes that owe their value in wool dyeing to the fact that the dyeings after being treated with copper sulphate become very fast to light and washing. Three per cent. of each gives very full shades of bluish green or dark blue. The dyeing is done with Glauber's salt and acetic acid when reddish shades are got; these in a bath of copper sulphate turn green or blue.
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 regardsfastness; with the 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.
Itcomes into this country in the form of lumps, which have a dark 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, andthe material exposed to the air, 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 theresult of such 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° to 125° 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 vatis a 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° 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 NaHSO2, 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 vesselwhich is fitted 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° to 60° 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° 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° 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 ofprocedure 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° 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° 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° 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 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° C., add 1/4 lb. of a mixture of 1-1/4 gallons bisulphite of soda, 52° 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° to 2° 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° to 212° F. is attained. Then 15 lb. of carbonate of potash are added and the liquor is allowed to cool down to about 120° 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 woadvat, and in consequence is 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° to 120° 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 itvery close in this respect. The vat is made as follows: To 50 gallons of stale urine 4 lb. of common salt are added, and the mixture heated to from 120° F. to 140° 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° Tw. strong are mixed. Then 8 pints caustic soda lye of 72° 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° 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.
Thisforms what may be called a "mother," or stock vat, from which 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° Tw., stirring well so as to keep the temperature down. Then add 3 pints caustic soda lye of 72° 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 fastto rubbing are desired, should be 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 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.