DYEING DIRECTIONS

The application of Basic colors to leather dyeing will be discussed later. We shall now discuss their application to basketry materials, such as straw, raffia, willow, and the like, where they will be found useful.

It will at once be noticed that these dyestuffs are far more powerful than any thus far met with in these lessons. Indeed, while there will be needed, for full shades of the Vat colors, pastes from about 15% to 20% of the total weight of the dry materials, of the Sulphur colors from 7% to 10%, of the Salt colors from 4% to 6%, and of the Acid colors from 1½% to about 3%, most of these Basic colors will give very full shades with from ½% to 1% of the total weight of dry material.

These Basic colors do not dissolve readily in water, but are easily soluble in alcohol, and also in even very dilute acids. Acids form salts with the dyestuffs and these salts dissolve when the free coloring matters do not. Accordingly the Basic colors should always be dissolved carefully in a separate cup or vessel, using hot water, and adding, for each spoonful of dyestuff, two or three spoonfuls of acetic acid or, if more convenient, of strong vinegar.

The color, thus dissolved, should be added to warm water in the dye-pot, preferably through a fine strainer or piece of cheesecloth, to avoid any undissolved particles which would cause spots. The well-wetted goods are immersed in this dye-bath, and turned, either in the cold or with gentle heat, until the desired shade is reached, or the bath is exhausted. The material is then taken out, rinsed once or twice in water, cold or warm, carefully dried, and, if necessary, straightened and pressed or ironed out.

Straw.—Care must be taken when dyeing these materials to have them quite free from grease and dirt, before dyeing them. If they do not wet readily and evenly, after being soaked in warm water for a couple of hours, they should be carefully washed in warm soapsuds, and thoroughly rinsed. The soap, however, should be of good quality and, especially with straw, either in the form of straw braid or made up into hats, no soda or other free alkali should be allowed in the bath, for fear of injuring the surface and destroying the gloss. This last is sometimes improved by dipping the straw, after dyeing and rinsing, into a weak bath of Castile (olive oil) soap, or of Turkey red oil (about one tablespoonful to the gallon), before it is dried.

In dyeing straw, the greatest pains must be taken to dye it evenly. Braid should be tied up in loose hanks or bundles, so that the dyestuff can penetrate readily into every part; and with a loop of tape or string, by which it can be raised or lowered in the dye-bath. It should be kept in motion sufficiently to cause uniform circulation of the liquid. The dye-bath should not be too strong, especially at the beginning, and should be heated slowly to the boiling point, where it should be kept for half an hour or so, to insure penetration. It is best to add the dyestuff in small portions, from time to time, as the bath becomes exhausted, lifting the goods out of the bath each time, and stirring in the new color before putting the goods back again. If the goods once become uneven it is very hard, if not impossible, to get them level again, or to strip them fully, without spoiling the materials. The best thing to do, if this misfortune overtakes them, is to dye them some dark color, where minor irregularities will be covered up and pass unnoticed. In other words, “Dump it in the black,” as the dyers say.

Ladies’ straw hats are dyed in just the same way as the loose braid, the same care being taken to clean and wet the goods thoroughly, and to dye evenly. It is often of interest to experiment with old hats of good material, but faded, and to dye them up some pleasant new shade, and the ribbons and trimmings to match. Sometimes the remains of the old coloring will strip well by washing in hot soapsuds, and sometimes by soaking in warm water containing about one tablespoonful to the gallon ofsodium hydrosulphite—the same salt that was used as a reducing agent for the Vat colors in the last chapter.

If the color comes out well, it is then easy enough, after thoroughly rinsing, to dye them any desired shade. Otherwise they can be dyed Navy Blue, with a good shade of Methylene Blue and a trace of red, or Seal Brown, using a large amount of red and a little yellow and blue; or they can be dyed black with a black dye, such as one of the so-called Leather Blacks, usually made by mixing a deep purple with a yellow, or one of the strong, powerful Basic greens with red.

In general, a well dyed piece of braid is supposed to show smooth, even coloring, good gloss, and good penetration of the dyestuff into the folds of the straw. There are, however, decided possibilities for the intelligent worker to obtain more interesting effects with but little trouble. It is very easy to use the principles, already explained, of rainbow dyeing, for straw braid, and beautiful effects can be obtained in this way, though it would need an artistic as well as an experienced milliner to fully utilize the same in making hats. But it frequently happens, when dyeing coarse braid without boiling, that the dye penetrates unevenly, from the edge towards the centre. Very pretty shaded effects can be produced in this way, the general color being uniform, and yet the straw, when looked at closely, showing tints instead of one flat, uniform shade. By dyeing the straw a solid color first, and then shading it in this manner with a different color, very interesting effects can be produced.

It may be worth while to mention here that, when bought at wholesale places, it is astonishing how cheap the raw materials are. Bodies of straw, chip, etc., framing wire, white satin ribbon, artificial flowers, wing feathers, etc., from which not only pretty but even handsome and elegant head coverings can be created, and cost next to nothing at wholesale. The mechanical part of dyeing all these things can be learned in a very short time; after that the possibilities for a skilled worker, who has a good eye for color and can dye to the desired shades herself without having to hunt them far and near, are very large.

Raffia.—This is a material so widely used in the public schools, as well as by craftsmen, for weaving baskets, that it is well worth while to pay more attention to the dyeing of it. It is quite cheap, and very bulky, and takes these colors extremely well. So that it is one of the most satisfactory of all raw materials to experiment with, especially if there is a school or workshop at hand, where the dyed goods can be utilized.

The raffia should be shaken out thoroughly, and soaked in soft water over night, or at least for several hours, to thoroughly wet and soften it. If even shades are desired it can then be dyed, just like straw braid, in a warm dye-bath containing the dyestuff, previously dissolved in diluted acetic acid or vinegar.

It is much more interesting, however, to dye it rainbow shades from the start. If red, blue, and yellow dyestuffs are dissolved separately, in different cups or pitchers, these solutions can be used to replenish the large dye-pots of the same colors. To keep the colors reasonably clear, and prevent them from speedily degenerating into “mud,” it is well to keep on hand one or two rinsing-pots, full of warm water, or to have a sink near at hand, where each hank or bundle of raffia should be rinsed after being taken out of one dye-pot and before going into the next.

The raffia, when thoroughly wetted out, should, for convenience’ sake, be made up into separate loosely-tied bundles, with a loop on each by which to handle it in the dye-bath without staining the hands. It is well, too, to have some oil-cloth around, for these bundles drip a good deal, and the dye-liquor will stain anything of an animal or vegetable nature with which it comes in contact. After a little experimenting with dipping these bundles first into the first dye-pot and then—rinsing each time—into the other two, it will be easy to get the general effect of any particular shade, although, when examined closely, the fibre will show the presence of all three colors.

It is interesting to notice, here, as previously with the Salt colors, how easy it is to modify and soften the harsh shades of the individual unmixed dyestuffs. And, as before, it is very interesting as well as very useful to dye some bundles even shades of some important compound color, such as brown, for instance, or olive green, or steel grey, and to notice how the color is changed on the fibre by adding a little more red, or yellow, or blue to the bath.

The “eye for color” obtained in this way is of the greatest possible advantage to a dyer, whether amateur or professional; and where, as in this case, the materials are cheap, easy to dye, and possible to utilize, every advantage should be taken of the opportunity.

Permanent Colors on Basketry.—While for most purposes the straw, raffia chips, willows, etc., dyed with Basic colors will be found satisfactory enough, it is best for craftsmen who are making a specialty of very high-grade baskets, to use some of the fast Acid colors, described and listed in the next chapter, for their reds and yellows, and for all mixed shades in which these two colors play an important part. The Acid dyes are applied in a boiling bath, with the addition of a little acetic acid, and, while not fast to washing, and not imparting their colors as readily as the Basic dyes, can be thoroughly depended upon, even in light and delicate shades, against the action of sunlight. Salt dyes can also be used, in a boiling bath with the addition of some salt, but, excepting in some special cases, are not superior to the Acid dyes, although somewhat faster to washing.

Chapter VIII
THE ACID COLORS

The discovery and introduction into commerce of Mauveine and the other Basic dyes, focussed the attention of chemists, all over the world, upon this new and important application of their science. And it was soon noticed that certain organic bodies, of a decidedlyacid character, had the power of dyeing wool and silk. These early dyes were so-called “nitro” compounds, formed by the action of strong nitric acid upon derivatives of coal tar, and in most cases they gave strong and brilliant, but rather fugitive, shades of yellow. The most interesting of these, perhaps, was the compound known as “picric acid,” which at one time was considerably used for dyeing silk yellow. Now it has been abandoned for that purpose but is manufactured on an enormous scale for use as an explosive.

These original acid dyes were of little importance. But in the early seventies chemists began to make use of a reaction—known as “diazotizing”—for making new organic compounds by the coupling of aniline or bodies similar to aniline, with all sorts and kinds of other compounds derived from coal tar. The number of derivatives of this sort proved enormous, and many of them had more or less valuable dyeing properties. And in a very short time new dyestuffs had been discovered, good, bad, and indifferent, numbering not hundreds, but thousands.

A very few of these so-called “Azo” dyes were of the Basic class, like Bismarck Brown, mentioned in the last chapter. Others, discovered ten or fifteen years later, constituted the class of Direct Cotton colors or Salt colors. But the great bulk of these colors belonged to the so-called “Acid” class, forming salts with bases and alkalies, and being liberated from the salts by strong acids.

The number of Acid Azo colors is very large. In the catalogues of commercial coal-tar colors there are some two hundred and fifty of these dyes which have been picked out of the rest as having sufficient value to be carefully described, and to have been placed on the market by the great dye houses. Most of these are red and orange colors, with a few yellows. As a rule they are brilliant and clear, but, with a few exceptions, not particularly fast to light.

When these were introduced it was soon recognized that they were of practically no value for cotton and linen. They are as a rule much more soluble than the Basic dyes of the foregoing chapter, and hence are occasionally used as stains for wood, rattan, and other vegetable materials where considerable penetration is needed, without fastness to washing. But such use is of little importance.

Properties.—Acid dyes are almost exclusively employed for dyeing wool, silk, feathers, and other animal fibres, and for this they are extremely valuable. The introduction of the Acid Azo colors so simplified and improved the dyeing of wool and silk, that every effort was made to increase the range of colors. And when it was found that the Azo colors were weak on the line of blue, purple, and green, efforts were made, which after several years proved successful, to change the various powerful Basic dyes, the Methyl Violets, Fuchsin or Aniline Red, Aniline Blue, Malachite Green, and the rest, into Acid dyes, so that they could all be used in the same dye-baths. This has resulted in a very wide range of colors indeed, for the Acid Azo colors cover fully all the shades of yellow, orange, and especially of red, from scarlets of all sorts and kinds to deep full crimsons. And then the remaining shades are covered by the acidified or sulphonated Basic colors.

These latter, by the way, though very brilliant and strong and rich, are no faster to light than the original Basic colors from which they are derived. Of late years the Acid colors have held their own, and still monopolize the commercial, as well as the special, dyeing of wool and silk excepting under unusual circumstances, when considerable fastness to washing is required.

With these dyes, as in the case of the Basic dyes, the fastness to washing is of little or no consequence to the craftsman. Nobody expects to scrub hand-dyed leather; and woollen and silk goods, unless specially prepared, are not supposed to be turned over to the tender mercies of the family laundress. However, it may be well to emphasize here the fact that these dyes are as a rule “stripped” quite readily by boiling in a neutral soap bath. And when the craftsman wishes to dye wool or silk fast to washing, he must either use the Salt dyes, in a boiling bath, or must dye, with special precautions against tendering, with either the Sulphur or the Vat Dyes.

With regard to light-fastness, however, the case is different. A great many hundreds, possibly even thousands, of Acid dyes have been discovered, and scores of them, covering every shade, can be obtained in the open market. Most of these are of but little permanence, but a few products, from each of the great color houses, can be selected, whose fastness to light is extremely satisfactory. The dyes in the following list can hardly be considered as fast as the Vat dyes, previously described, but are probably faster, as a class, than any other class mentioned in this book. They would rank at the very top of the second class, and some at least would fairly enter the first class, being absolutely satisfactory against even the strongest sunlight.

A series of skeins, dyed all colors of the rainbow, including many delicate light shades, with a red, yellow, and blue dye of those mentioned below, withstood an exposure test which quite ruined a similar set of skeins dyed with the very best natural dyestuffs. And a large hand-woven rug, made of wool dyed light shades with the same dyes, was placed for two weeks on a roof in New York, half of it being covered with boards and the rest exposed to the direct action of the July sunlight, and at the end of this time it was impossible to notice any difference in shade.

The colors in the following list are to be used, principally, for wool. They will all dye silk, leather, and feathers, but in the chapters dealing with those materials some additional dyes may be mentioned, which are specially suited for them.

List of Selected Dyes.—

Badische—Palatine Scarlet A, 3 R
Palatine Light Yellow, R
Tartrazine (yellow)
Wool Fast Blue, B L
Cassella—Brilliant Cochineal, R R
Acid Yellow, A T, conc.
Tetracyanol, S F
Elberfeld—Azo Crimson, S
Fast Red, A
Fast Yellow, 3 G
Alizarine Blue, S A P
Cashmere Black, 3 B N
Kalle—Biebrich Acid Red, 2 B
Wool Yellow, T A
Nero cyanine Blue, B
Nero cyanine Black, D
Metz—Fast Acid Red, M
Fast Acid Orange, G
Fast Acid Yellow, 3 G
Fast Acid Blue, B B