DYEING DIRECTIONS
The Acid dyes, like the Basic, are used in an acid bath, but for a different reason. With the Basic dyes acetic acid or some other weak acid is added, for the purpose of readily dissolving the color. In the case of the Acid dyes, however, the dyestuffs are almost always put on the market in the form of the potassium or ammonium salts of the color acid. And the presence of some acid is always necessary, to liberate the color acid, and allow it to combine with the basic principles existing in the animal fibres.
For Wool.—The goods, well washed and soaked, are warmed gently in a bath containing, besides the dyestuff dissolved in plenty of water, a little sulphuric acid and a good deal of Glauber’s salt. Both acid and salt should be free from iron, or the shade will be dulled.
The amount of acid to be used may vary between considerable limits without affecting the results. If too much is present, there is danger of injuring the feel and the lustre of the fibre. If there is not enough acid in the bath, the color will wash right out of the wool, as soon as it is rinsed. In general it is well to start with about one tablespoonful of dilute (30%) sulphuric acid for each gallon of dye-liquor and about twice that amount of Glauber’s salt.
It is hard to tell just what is the function of the Glauber’s salt. It seems, however, to open up the pores of the wool in some way, and to make it dye more evenly and deeply. The bath is gently heated, with constant stirring of the goods, until the right shade is produced, or, if it is desired to exhaust the bath and so waste no color, until near the boiling point.
The goods when taken out of the dye-bath must be washed very thoroughly, to remove the last trace of acid, which otherwise on drying would ruin the wool.
It must be remembered that these Acid dyes hardly affect cotton in the least, and so the goods dyed in this way must be free from vegetable fibres, if level dyeings are to be obtained.
In dyeing wool skeins commercially it is, of course, of the utmost importance to have the colors perfectly level and uniform. This uniformity is obtained easily enough, when using these Acid dyes, by having the wool thoroughly wet before placing it in the dye-bath; by having it well loosened out and well stirred so that the color will penetrate evenly every part of the material; and, finally, by starting the bath at a moderate temperature, and heating it gradually, until the proper shade is obtained.
For handicraft dyeing the student is strongly advised to practise shaded and irregular effects, the so-called Rainbow dyeing, with wool in skeins, just as, in previous lessons, with raffia and with cotton. By using coarse heavy yarns, very beautiful two and three color effects can be produced, which, when used for embroidery or weaving, will prove most interesting.
Great care must always be taken, in wool dyeing, to preserve the lustre and the soft effect of the wool, and to avoid felting. This can best be done by using moderate amounts of acid, by dyeing at moderate temperature and never raising the dye-bath quite to the boil; and finally, by handling the goods as little as possible in the acid dye-bath, consistent of course with exposing every portion equally to the action of the dyestuff. Cotton skeins can be worked and rubbed, and pulled, and thrown up and down in the hot dye-bath, without fear of injuring them. But wool should be handled carefully, and worked in the dye-pot quietly and gently, just sufficiently to accomplish two results. First, the wool at the bottom of the pot should be raised by a lifting and turning motion and replaced by fresh material; and second, when the wool is lowered back into the liquor it should be loosened, so as to allow the dye-liquor to penetrate the mass.
Chapter IX
DYEING FEATHERS
The use of feathers and, especially, of ostrich feathers for millinery has, during the past few years, increased to enormous proportions. Besides the home product, from California and the Western States, which, however, is but small, the importation of raw feathers from abroad has averaged, during the past two or three years, nearly eight millions of dollars. As yet, the dyeing of these feathers is almost entirely confined to professionals—their processes, although simple, not being generally known or published.
As before mentioned, feathers, like other animal products, can be colored with ease by either the Basic or the Acid dyestuffs. In practice, as with wool and silk, the Acid dyes are universally used, because of their greater variety, their greater fastness to light, and their better levelling properties. To use the Acid colors with success the following points must be carefully considered. First, the baths must be such as not to ruin or “burn” the feathers, i.e., they must leave intact the tiny barbules upon the barbs or “flues,” as the dyers call them, which make the feather look soft and full and not stringy.
Second, the quill must be fully dyed, and the shaft, or stem of the feather, must also be colored just as well as the flues. This is a very common defect in feather dyeing. The quill, being hard and stiff and horny, is much more difficult to penetrate with the dyestuff than the soft, delicate fibres. If the feather, therefore, is dyed hurriedly or carelessly, the latter may be colored dark and full, long before the quill or the lower part of the stem has been dyed at all. This necessitates painting the stem after the finishing process, with oil colors, to match the rest of the feather.
Finally, after dyeing, the feather must be properly finished so that the flues will not look woolly on the one hand, nor stringy on the other hand, but soft and full.
The whole secret of feather dyeing lies in the proper attainment of these three requirements, success in which depends respectively upon (a) the composition of the dye-bath, (b) the method of dyeing, and (c) the finishing process.
(a) The Dye-bath.—As is universally the case when using Acid dyes on animal fibres, the bath must be distinctly acid, in order to release the free color acid from the dyestuff, which, in its commercial form, is a salt. A very little experimenting with ostrich feathers will show that the presence, not only of mineral acids like sulphuric or hydrochloric, but even of the much milder organic acids, like acetic or citric, is liable to “burn” the feather badly and convert a well barbuled flue into a bare fibre which, under no conditions, can look other than stringy. The acid commonly used by the professionals is oxalic acid, but, of late years, dyeing chemists have been introducing into the dyeing industry the use of the volatile and pungent formic acid, and in the dyeing of ostrich feathers this acid has been found particularly advantageous. Excepting when a large number of feathers, strung together on a line, are to be dyed the same color, it is customary to dye feathers in an agateware pan or flat dish, and about two-thirds of a teaspoonful of formic or oxalic acid in a pint of water, is about the right proportion for one or two feathers at a time.
(b) Method of Dyeing.—
Softening the Feathers.—Before immersing the feathers in the dye-bath the greatest pains should be taken, first, to thoroughly cleanse them, and, second, to thoroughly soften them. As a rule, the feathers are bleached before dyeing and in this process they generally lose all of their original grease. But if they show signs of wetting unevenly when plunged into hot water, they should be carefully scrubbed with Castile soap and hot water, and well rinsed till the last trace of soap has been removed.
The clean feathers should then be thoroughly softened by immersing them in hot water. This is especially important as regards the quills and the stems, which may have to soak for half an hour or more before they are soft enough to take the dyestuff.
Dyeing the Feathers.—After softening, each feather is held by the tip, and laid, butt first, in the dye-bath. For light shades the dye-liquor may remain cold, but for darker shades it is best to enter the feathers at a low temperature, and raise the latter very gently till the right shade is reached, or the bath is decidedly hot, although still far below the boiling point.
Above all, care must be taken to dye the quill and butt first, and to keep them in the bath very much longer than the flues and tip. The latter will dye in a minute or two, but to thoroughly stain the former may take twenty minutes or half an hour.
(c) Finishing.—When the desired shade has been reached, the feather is taken from the bath and rinsed thoroughly in warm water, to get rid of the loose color. Then it must be “starched.” This is the technical name for the drying process, and is very different from the laundryman’s idea of “starching,” although the two processes have occasionally been confused, with most disastrous results, as far as the feathers were concerned.
Dry-starching.—After the dyed feathers have been thoroughly rinsed, they should be partially dried, by wiping with a soft piece of cloth, like a handkerchief or piece of cheesecloth, and then laid flat on a piece of stiff paper and covered with a heaping tablespoonful or so of dry, finely powdered starch (on a small scale the quality known as “Electric Starch” is eminently satisfactory). The starch is thoroughly rubbed into the feather with the fingers, and then the feather, full of starch, is beaten and dusted against the edge of the table or the back of the hand until the starch has all been shaken out. After one or two repetitions of this process, the feather will be found not only dry but with the barbules properly filled out. Sometimes the feather, thus treated, has a woolly look, the starching process having gone too far. In this case it should be dampened in cold water, and restarched.
Under no circumstances should any starch paste be allowed to touch or form on the flues. The starching must be done in the cold and with the unbroken starch grains.
Wet-starching.—Some dyers prefer wet-starching to the dry process just described. In this process, the feathers, after dyeing and rinsing, are worked for a minute or two in a thick milk (not paste) made by stirring one or two large tablespoonfuls of dry starch in half a pint or so of cold water, till all the lumps have been broken up. After this milk has been thoroughly rubbed into every part of the feather, the latter is taken out, dried roughly by wiping with cheesecloth, and then by wrapping between blotting paper or folded cheesecloth and running carefully through a not too tight wringer. The feather is then taken out and thoroughly dried, either by laying it on the table in the sunlight or in a warm room for some time, or, if very great care is taken, by holding and moving it over a hot-air register, or high over the stove or gas flame. Of course, if this is done carelessly and too great heat is applied, some of the starch grains will be converted into paste, and the feather probably ruined. When thoroughly dry, “bone dry,” as the dyers call it, the feather is beaten against the back of the hand, or edge of the table until all the starch is shaken out.
Dyeing in the Starch.—When dyeing light shades time may be saved by dyeing and wet-starching at the same time, in the same bath. The feather, thoroughly soaked in hot water, is placed in the starch milk, to which a quarter teaspoonful or so of formic acid and a little dyestuff have been added, and then worked, in the cold, until the proper shade has been reached, the starch being taken up at the same time. Then on drying and beating, the feather will come out both dyed and finished. This has the disadvantage of leaving a little acid in the finished feather, but when using small quantities of oxalic acid, this is of little, if any importance.
Suggestions as to Feather Dyeing.—These processes should enable any intelligent craftsman to dye even the most costly and most delicate feathers without danger of spoiling them. Shade effects in one, two, or more colors can be easily obtained by the use of a little ingenuity, remembering always that the quill and the stem are very much more difficult to dye than the flues or tip. It will be remembered that comparatively few ostrich feathers are now used, singly; the plumes so abundantly in use, nowadays, being almost invariably built up by sewing two or usually three feathers together, one underneath the other, the stem being carefully shaved down so as not to make them too clumsy.
Very charming effects can be obtained by dyeing the individual feathers different but harmonious colors, and then combining them into one plume later. But, usually, the plume is made first, and then dyed afterwards. It may be suggested, here, that very beautiful effects can be produced by taking large, handsome, single feathers, before they are bleached, and dyeing them a pleasant shade of red or blue or of some mixed color. The natural black of the feather, with its irregular markings, often gives very interesting results, and the expense is much less than that of a built-up feather.
After the starching process, the dried feather is usually finished by “curling,” a process simple enough in itself, but which had best be left to the professional, for fear of injury. The bleaching of feathers, also, is a process which is hardly to be attempted by the amateur, unless he is prepared to spend a good deal of his time and money in experimenting. The process, however, is well understood by dyeing chemists and can be learned without much difficulty, by a careful student with some knowledge of chemistry.
Stripping Feathers.—By soaking in warm water, containing a teaspoonful or so of ammonia water to the pint, and then carefully washing with soap and hot water, these Acid colors can be, as a rule, stripped from feathers almost entirely. This does not, to be sure, improve the original quality of the goods, but, carefully done, its bad effects are hardly, if at all, perceptible, and it enables the dyer to remedy a bad piece of dyeing, or to dye an old feather that has become faded or discolored by exposure. This, of course, does not apply toblack dyed feathers.
After white feathers have been worn for some time they generally become soiled and yellow. If the stock was good to start with they can be immensely improved in appearance, if not made quite equal to new, by simply scrubbing them with a piece of Castile soap, in hot water, and then, after thorough rinsing, by dyeing them, in the starch-bath, with a very faint trace of blue or bluish violet.
Black Dyeing of Feathers.—This is the most difficult process in feather dyeing, and, as a rule, should be avoided by the amateur. It is impossible, so far, to get a thoroughly good black by the use of any artificial dyestuff, or any simple process. The best Acid blacks on the market, dyed with the greatest care, give a color to feathers that by themselves may look pretty well, but, when compared with first-class products, show dull and grey.
The only satisfactory blacks, so far, are produced by a long and tedious series of operations, depending on mordanting for, and dyeing with, logwood. As a rule, the professional black dyer—and really good ones are few and far between—allows at least five or six days for the process, the different steps of which he usually guards as a valuable secret, which indeed it is. The writer possesses one or two of these formulas, obtained, as special marks of favor, from first-class dyers, but has never had occasion to test them thoroughly, and therefore is unwilling to publish them here. Good dyeing chemists have tried again and again to shorten and simplify the process, and have had some success. But to this day no color has been found to replace logwood, and this black dyeing of feathers is perhaps the only dyeing problem that has not as yet been satisfactorily solved with the aid of modern dyestuffs.
Painting Feathers.—Some dyers, instead of dyeing feathers, paint them. They dip the cleansed and carefully dried feather, for a moment, into a bath of oil paint, thinned greatly with gasolene. The feather is then taken from the bath, dried by waving in the air, and, when thoroughly dry, finished by beating and, if necessary, with a light dry-starching.
The results, for colors, are fairly satisfactory but are not so permanent as the dyeing process. In an oil paint the solid coloring matter, or pigment, is ground up finely in boiled linseed oil, an oil which has the property of drying to a firm varnish when exposed to the air. This mixture is thinned with turpentine or gasolene to the desired consistency before using.
It is evident that, in coloring feathers, if enough oil is applied to fasten the pigment very firmly to the flues, there is danger at the same time of plastering the fine barbules so that they will never get back to their proper places, and the product will be hopelessly stringy. On the other hand, if the amount of oil is so small, thanks to the abundant thinning with gasolene, that there is no fear of its sticking the barbules together, there will hardly be enough oil left to firmly fasten the pigment to the flues, on drying, and the color is apt to rub, and to wear off quickly.
Paint, thinned with gasolene, has been applied to feathers occasionally by means of stencils, some of the so-called “barred” effects, looking like the feathers from a barred Plymouth Rock hen, being made in this way—the color, black paint or varnish, greatly thinned, being applied by means of an “air brush” or atomizer. Occasionally very large, wide, and handsome feathers have appeared decorated with flowers and other figures, in bright colors, applied in the same way with an air brush, sometimes with the help of stencils, but generally free-hand. These effects are often rather crude and inartistic, but there is no reason why, skilfully used, this method of decorating the backs of feathers might not produce interesting effects.
Chapter X
LEATHER AND LEATHER DYEING
So far as can be learned, in every part of the world, the first materials used by man for clothing and coverings were the skins of animals. In its natural condition, however, the hide stripped from a dead animal has certain properties which greatly interfere with such use. When dry it is stiff and hard; when moist it rapidly decomposes, and when exposed to hot water it swells and in time dissolves. These difficulties had to be overcome before skins and furs could be properly utilized. And, accordingly, in the history of every nation and race, one of the very earliest of all developing industries was the art of leather making; that is, of converting the hard and easily decomposed rawhide into a soft, pliable, and comparatively permanent substance, well suited for the use of man.
In most uncivilized nations this conversion was accomplished by rubbing and working some oily or greasy substance into the hide, until it was thoroughly soft and flexible. Thus, in our Indian tribes, the old squaws would turn the deer skins and the pelts of various fur-bearing animals into beautifully soft and strong leather, by rubbing and working into them the brains of the animals. The Esquimaux and other Northern tribes from time immemorial, too, have worked out this method with great perfection. Indeed without it they would have been unable to survive at all.
In other parts of the world it was discovered that rawhide could be made more durable by treatment with metallic salts, especially with alum, and then, by softening this product by rubbing in some oily material, a very fair leather could be produced. On the other hand, in warmer climates, as for instance among the Egyptians, the very earliest records show the use of vegetable extracts, containing the substances now known as tannins, for softening and preserving skins; and these races understood the art of dyeing, painting, gilding, and embossing the leather thus made, and used it for shoes, straps, aprons, and harness.
The Romans and Babylonians were famous for their leather industry, and the ancient Romans not only imported but manufactured it themselves, and used it freely. In the Middle Ages the greatest developments in the art were made by the Moors in Spain, whose leather, commonly called Cordovan leather, from the city which was the centre of the industry, has probably never been equalled for beauty and importance. This Cordovan leather, of which fine specimens are still to be found in museums and private collections, was made of sheepskin, tanned with bark. It was ornamented with silver foil, laid on a backing of size, and covered with a yellow varnish or lacquer, sometimes tinted with bitumen. This protected both the leather and design very perfectly from injury by air or moderate moisture, and, being done on a large scale with splendid designs, was used largely for handsome wall coverings, competing favorably with tapestries manufactured in France and elsewhere for the same purposes.