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Previous Next The best candle and soap tips online! TECHNICAL TREATISE ON SOAP AND CANDLES. THE FABRICATION OF SOAPS. 295 contain a considerable portion of lye, which then renders the soap less neutral and less pure. After resting forty to fifty hours, the kettle is uncovered, and the scum on the surface of the- soap carefully removed. This scum is utilized in a new operation. The soap which is fluid, syrupy, and well melted, is dipped or pumped into the frames. If an iron-wire sieve is placed above each frame, and the soap passed through it, the foreign substances contained in the paste will be separated. The bottom of the kettle being reached, care must be taken not to dip up any of the lye with the soap; the latter is always easy to recognize by its golden color, while the lye lias a brown, blackiskishade. As soon as the lye appears, manage the ladles-an such a manner as only to remove nothing but the surface matters; but whatever be the care taken there is always a small quantity of the lye mixed with the soap. To prevent the inconveniences which would result from the mixing of the lye with the refined soap, it is better to pour the last portions of soap into a cylindrical vessel, provided with a cork at the bottom. By resting, the lye precipitates, and the soap specifically lighter floats on the surface. Then draw off the lye, and pour the soap into the frames. Paris manufacturers slightly perfume this soap, to mask the generic odor of the oleic acid; they generally add two ounces of artificial oil of bitter almonds (oil of myrbane) for 100 pounds of soap. Stirring the Soap in the Frames.—It would not have been enough to bring the soap to the proper point of coction and purification, if it could not be had perfectly homogeneous. It is true the soap would have the essential qualities which constitute a good oleic-acid soap. It would foam and be detersive, but by the slow and gradual cooling it experiences in the frames, irregular marblings would be formed. It might even be often spotted by the lye, which would give it a very defective appearance. To obtain the s >ap in a smooth and homogeneous paste, it must be submitted to the stirring operation, which con- sists in agitating the soap in the frames. The stirring must be continued until the soap becomes nearly pasty, which is easily ascertained by the difficulty of moving the stirrer. The new crutching machine illustrated elsewhere is well adapted for this purpose. The equality and perfect homogeneity of the paste, depend essentially on the stirring in the frames; the more complete the stirring, the finer will be the soap. This operation is performed on almost all soaps, except the marbled soap, the marbling of which would be destroyed by stirring. The time of the stirring varies according to the nature of the pastes, their more or less complete liquefaction, and their temperature at the time they are introduced into the frames. But, as a general rule, soaps composed of fatty matters in which stearin exists in small proportions, and the liquefaction of which has been pushed too far, require a longer stirring than those made of fatty matters very rich in stearin. The stirring of olive soaps run into frames of about 2000 pounds, lasts from eight to twelve hours, according to the season; the stirring may be discontinued when the temperature of the mass is reduced to 43.3° or 48.9° C. (110° or 120° F.). After eight or ten days the frames are opened, and the soap divided into cakes. Thus prepared, this soap is brownish-yellow, but by being exposed to the air, it becomes white. At first its consistency is somewhat soft, but it becomes hard in a short time. When well prepared it is very detersive. In water it produces a very abundant lather, and is one of the best soaps. By the saponification of 6750 pounds of oleic acid of good quality, the amount of soap obtained is 10,687 pounds, or 155 per cent. The viscous lye from which the liquid soap has been drawn ofl*, being mixed with 10 per cent, of salt water at 25° B. and boiled for seven or eight hours, produces from four to five per cent, of its weight of a good soap, which only requires to be dissolved in a weak lye to get rid of the excess of saline substances it contains. This soap being mixed with the other increases the amount obtained from 155 to 158 or 160 per cent. 296 TECHNICAL TREATISE ON SOAP AND CANDLES. THE FABRICATION OF SOAPS. 297 When the soap is to be moulded it is divided into cakes, usually weighing one pound, and dried in the open air in summer, and in a drying-room in winter. We give rather full directions for this soap, as it is a very important article of commerce, utilizing a material that otherwise would find few uses, and we shall have occasion to refer to it again in describing the Swiss soaps and soft soaps. Of soaps made by boiling we have given those chiefly known to commerce, with hints that any skilful operator can apply with the materials on hand and make any modification of the kinds given, calling them by whatever names he may choose. There are several boiled soaps known in Europe as candleshop.com/cgi-bin/affiliates/clickthru.cgi?id=soforreal">wax soap or bleaching soap made from tallow and cocoa-nut oil, containing a larger percentage of water. Almond-grain soap, is a modification of the mottled soap of tallow, wherein the coloring is applied in a different manner, causing white lumps to appear, called almonds. The soaps made in this country as imitations of Marseilles soap or Castile soap are now made with a good deal of cotton-seed oil in combination with tallow, etc., and as they possess much interest we will here give the formulas for Castile soap, either white or mottled, made from cotton-seed oil as a base. CASTILE SOAP FROM COTTON-SEED OIL. In our Southern States, where cotton is grown in the greatest quantity and of the best quality in the world, the seed has long been known to have an abundance of oil, the extraction of which was very difficult on account of the adhering fibre. From this cause the seed was allowed to rot, and was used for manure. When, however, machinery was invented for hulling the seed, the oil could be extracted with facility. The large amount of hull and adhering fibre these seeds possess will be understood when it is known that it sometimes takes five bushels of seed to make one bushel ready for the mill. The hull and fibre are used for paper stock, and are, of course, very valuable. When it was found possible to remove the hull and make Previous Next
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