PRACTICAL DYEING
Before proceeding to the practical dyeing instruction it is well to say a few words about the equipment needed for the work.
Fortunately no elaborate or expensive outfit is necessary, even for the beginner. And after one has had a little experience, it is astonishing what an amount of interesting, and even important work can be turned out with a few of the very simplest utensils. The essentials may be set down as follows:
Dye-pots.
Heating devices.
Stirring rods, or dye-sticks.
Wringers.
Drying arrangements.
Dye-pots.—For this purpose, common agateware vessels are best and most convenient. There should be varying sizes to accommodate different amounts of material to be dyed. The so-called “miner’s cups,” which are agateware cups holding a pint or more, are large enough for practical work, when single skeins are being dyed. For large pieces use the wash boilers which vary in capacity from one to five gallons. It is always best, especially for amateurs, to dye in one batch enough material to complete the work on hand, whether rug, portière, or piece of tapestry. This avoids the necessity of exactly matching the shade afterward.
For three and a half to four pounds of cotton rags, such as are used in making rag carpets, three and one-half gallon pots are about the right size. This amount of material will be about enough for the filling for one rug about 6×4 feet, woven on a hand loom.
Heating Devices.—Work may be done over any flat-topped stove that burns wood or coal; gas is, of course, an advantage and so is an oil stove, as with these the heat may be regulated very exactly and much time saved. For actual work, a stove with space for four or five pots is the most convenient type to use.
There should always be one large pot set aside for heating water, another for boiling out the raw goods, and still a third for boiling out and brightening the finished materials with soap, when very fast colors are used on cotton or linen; and each of these pots should be reserved for its special purpose andnot used for dyeing. This will avoid the danger of staining the goods.
The top of a kitchen range will do for heating, but whenever possible, it is best to have a separate stove, so placed that the top of it will not be more than about twenty-four inches from the ground or floor. This enables the operator to look down into the dye-pot and so avoid strain, and the consequent excessive fatigue while stirring the goods.
Stirring Rods.—While the material is being dyed, it should be kept in constant motion. When working with small amounts of material, or with goods such as straw, raffia, muslin, or silk in skeins, which are delicate and easily spoiled, it is far more satisfactory in every way to use heavy glass rods for stirring. These are rather expensive. They are about fifteen inches in length and well rounded at the ends. If carefully handled and thoroughly washed, they are always clean and smooth. Care must, of course, be exercised in their use, as sudden variations of heat and cold may cause them to crack or chip, and lifting or stirring large quantities of heavy materials—anything above five pounds—is liable to break them. In these cases, it is best to use wooden dye-sticks. Broomsticks or dowel sticks, cut into two-foot lengths, with the ends rounded carefully by whittling with a sharp penknife, are excellent substitutes. For careful work it is necessary to have several sets of wooden dye-sticks—two for each main color at least—and these must be carefully washed each time after using, or they will stain cloth that is being dyed light shades. They are bound to get soft and rotten before very long, from the action of the alkali in the dye-baths, but they are easily replaced.
Good rubber gloves are extremely useful while dyeing, to protect the hands not only from being stained and discolored by the dyes, but also from the action of the chemicals—especially while dyeing with indigo and other dyes wherein the caustic alkalies are employed.
After some experience in the use of dye-sticks, however, it will be found comparatively easy to handle the materials, in and out of the dye-baths, with the sticks, without at any time taking hold of them with the hand. Nothing demonstrates more clearly the skill of the dyer than the ability to carry, immerse in the dye-bath, stir, take out, wring, and rinse the materials without getting stains on either clothes or fingers. On the other hand, the amount of slopping that can be accomplished by a careless, but enthusiastic, amateur must be lived with to be thoroughly appreciated.
Wringers.—Both before and after dyeing it is very important to have at hand a good clothes wringer, preferably with metal frame. In fact, for very careful work there should be two wringers; one to wring out the raw materials after boiling them in soap and water, or, if clean, in plain water, to insure that they are thoroughly and evenly wet; and the other to wring out the excess of dye-liquor from the goods before rinsing, or, as in some cases, before hanging up to oxidize. The rubber rolls of these wringers should be kept clean by scouring with soap and sapolio immediately after finishing the day’s work, and by carefully rinsing free from dye-liquor.
It is always well to keep on hand near the wringer a supply of clean blotting paper, or cheap filter paper, or even soft, dry cheesecloth or muslin. For by wrapping the materials that have just been dyed, in any of these, and then running them backwards and forwards through the wringer, it is possible to dry them with a minimum of time and exposure. This is particularly important in the case of natural and artificial silks, either in skeins or scarfs, of ostrich feathers, and of other light and fragile materials.
Drying Arrangements.—Sufficient room should be provided for hanging up the cloth to dry. An ordinary clothes-line, conveniently fastened, is the best means of support. For special purposes, where the material handled is very delicate or where the work is done in a classroom, a simple clothes-horse made of thick glass tubing, one inch or so in diameter and supported on a wooden frame, will occupy the least possible space and give the best support.
Chapter II
MODERN DYESTUFFS
The whole art and practice of dyeing was completely revolutionized once and forever, by the discovery in 1856 of the artificial dyestuff named mauveine, or, more commonly, mauve, a name, by the way, derived from the French name of the violet-colored mallow flower.
The discovery was made accidentally, by a young chemical student, William Henry Perkin, while experimenting in a very crude and simple way, with a view to forming artificial quinine from a curious oily body known as aniline. This aniline was originally prepared by distilling indigo in a dry retort, and it had received its name from the native Javanese word “anil,” meaning indigo. While thus prepared it was, of course, very expensive. But about this time methods were invented for obtaining this same compound in practically unlimited quantities from coal tar—that heavy, foul-smelling refuse of gas works—which, up to that time, had been not only useless but actually a source of annoyance and expense to the gas companies.
Perkin conceived the idea that, by partially burning or oxidizing it, this aniline might be changed into quinine. He made the experiment and there resulted a black molasses-like mass, very far removed from the white crystals he was hoping for. But by testing this with various chemicals, he found that hot alcohol dissolved part of it, and turned it into a violet liquid which had the power to dye silk and wool the same bright color. Finding that the color was fairly fast to light, and that it could be produced without too much expense, he took out a patent and, with the aid of his father and brother, set up near Manchester, England, the first factory for artificial dyestuffs.
His discoveries were at once published, and chemists all over the world began to manufacture and experiment with the new dyestuffs. Great factories were started all over Europe. From this beginning the manufacture of coal-tar dyestuffs, and more recently all their allied compounds, has become one of the most important and most profitable of all chemical industries.
The dyes first discovered, the so-called “Basic dyes,” were of great brilliancy and strength; but they were not of any particular beauty when used individually. Compared with the vegetable colors which preceded them, and especially the same shades we are accustomed to see in nature, these dyes were hard, coarse, crude, and very inartistic. This could be remedied, however, by mixing two or three of them together, such mixture tending to soften the different colors and blend all into pleasant and delicate shades.
A more serious difficulty was the fact that those early dyestuffs were usually quite fugitive to light or, at any rate, far less fast than the best of the vegetable dyes that preceded them. Besides, they did not fade true. In other words, a piece of cloth might to-day be a bright red, and after a few days of exposure to the sunlight, the exposed portions might turn a yellow, a white, or even some dark color; and, in any case, the change would entirely spoil the original color scheme.
By 1868, however, the artificial manufacture of alizarine, first by two German chemists, and then by Perkin himself, served to open up another whole class of new dyestuffs, which, when submitted to the proper tests, proved to be exceedingly fast both to light and to washing. In consequence, within a few years after this discovery, the commercial use of madder was everywhere abandoned. Chemists could now produce on cotton, linen, wool, and silk, practically the whole range of colors, brilliant and dull, hard and soft, light and dark, not only of a beauty, but of a fastness to light and to washing, never before surpassed, if indeed equalled.
| AT THE AGE OF 14 | AT THE AGE OF 22 |
AT THE TIME OF THE COAL-TAR COLOR JUBILEE—50 YEARS AFTER HIS DISCOVERY OF MAUVEINE
Since that time, not a year has gone by without scores of new dyestuffs being put on the market by some of the great color houses. Of late years special efforts have been made to simplify dyeing processes, and at the same time to insure the fastness as well as the beauty of the colors. At the present time it is possible for the veriest amateur, with practically no previous knowledge of chemistry or of dyeing, and with only intelligence enough to follow some simple directions, to get, in one bath, with very little expenditure of time, an immense variety of shades that are exceedingly fast to light and to washing. A very few years ago this result could not possibly have been obtained, except by some expert dyer, and then only after long and tedious, as well as difficult, processes.
We are all familiar with the constant complaint that it is now impossible to get goods dyed or printed in good, fast colors. For instance, take the brilliant scarlet calico commonly known as Turkey red. In the days of our grandfathers a piece of cloth dyed Turkey red would stand rain and sun, washing and scouring, and thefibre would wear out before thecolor would fade. But nowadays, if you buy Turkey red cloth for the purpose of covering cushions for a piazza-lounge, you will be fortunate if the color does not begin to change after three or four days in the open air.
The reason is simple. In the old days theonly way to get that particular shade was by dyeing the cloth with ground-up madder root, through a series of operations lasting the best part of two months. Now any capable dyer would be able to dye cotton that exact shade with any of, say, twenty different colors, most of which would not require more than one or two hours to dye. Out of these twenty dyestuffs, four or five, rather more expensive than the rest, would give just as fast, just as brilliant, and just as strong color as the good old madder color. But the rest, which are distinctly cheaper and easier to apply, would furnish goods which wouldlook exactly the same to the average purchaser, but which might notlast any time at all.
Naturally, the average manufacturer carefully instructs his dyer to furnish him with the “cheap and nasty” goods, not only because it costs less money, but also, unfortunately, because he reasons that “it will be good for business.” The manufacturer has the greatest sympathy with the inclination of the fastidious housewife to throw away anything that looks faded, and to buy in its place something new and fresh. Curtains or portières that hold their original shade indefinitely, he has little or no patience with. A calico dress that keeps its color so that it can be worn for a second summer, is an abomination not to be endured. And in every case, when complaint is made, it is always said to be the fault of the chemist who produced and put on the market such “horrid, fugitive dyes.”
As a matter of fact, it is simply a case of picking and choosing. There have been discovered, so far, several thousand different coal-tar dyestuffs of all sorts and kinds. Out of these, probably one hundred, or less, can be considered really fast to both light and washing. The remaining ones, most of which never were considered valuable enough to put on the market, vary in degrees of fastness, the poorest being simply stains which will “bleed” indefinitely with moderate washing, and which will turn almost any color after exposure for a few hours to sun and weather.
In the following pages, considerable pains will be taken to emphasize the names and properties of the very best and fastest dyestuffs in the different classes,[1] so that the results of work done with them can be depended upon.
[1] In some classes there are no absolutely fast dyestuffs.
Perhaps the most interesting thing, in connection with the whole subject of the artificial dyestuffs, is the enormous influence that they have had upon the life of the whole human race. This influence was but slightly appreciated, even by the chemists themselves, until a few years ago. The awakening dates from the time of the fiftieth anniversary of the discovery of mauveine, when from one end of the world to the other, honors were showered upon Sir William Henry Perkin, then grown old and nearing the end of his useful and prosperous life. It was then announced, and was for the first time generally recognized as true, that no one of the great discoveries of the nineteenth century—the steam locomotive, the steamship, the telephone, the telegraph, the gas light, the electric light, and the rest—had been more important to the world at large than the discovery of the first coal-tar dye. And probably never in the history of the world have such enormous results been produced from a single discovery, during the lifetime of the discoverer himself.