Soapmaking

“ Almost any fatty substance can be employed in soap-making; but the choice is naturally restricted by the price of the fat and also the quality of the soap desired. The most important of the animal fats are those of the ox and hog, and of the vegetable oils cotton-seed and coco-nut; it is also to be remembered that resin, although not a fat, is also important in soap-making. Ox and sheep tallow, with the addition of resin, are the primary materials for making the hard yellow or primrose soaps ”

“ Thus we can take a combination of tallow and cocoanut oil and make a great many presumably different soaps by combining these substances with caustic soda, by different methods of manufacture and by incorporating various other ingredients, as air, to form a floating soap, alcohol to make a transparent soap, dyestuffs to give a different color, etc., but essentially it is the same definite compound.
The manufacturer can best judge the brand of soaps he desires to manufacture, and much of his success depends upon the name, package, shape, color or perfume of a cake of soap. ”

“ Through the acid properties of the fats, the oleine, stearine, margarine, etc., which they contain, combine with the alkali to produce the saponified compound.
Hard soap is made with soda; soft soap with potash. The more oleine in the fat, the softer the soap; the more stearine the harder. Rosin is also largely used, sometimes to the extent of one-third the weight of the soap. It increases its hardness, makes it dissolve easier in water and forms a more copious lather.
The Most Economical Soap. Soap may be two-thirds water and still remain solid. Even dry, hard soap contains 20 or 25 per cent. ”

“ Soaps are distinguished into two great classes, according to their consistence; the hard and the soft; the former being produced by the action of soda upon fats, the latter by that of potash. The nature of the fats contributes also somewhat to the consistence of soaps; thus tallow, which contains much stearine and margarine, forms with potash a more consistent soap than liquid oils will do, which consist chiefly of oleine. The drying oils, such as those of linseed and poppy, produce the softest soaps. ”

“ The cold process for manufacturing soap is the simplest method of soap making, and the equipment required is small when compared to the other methods. All the more expensive equipment that is necessary is a crutcher, a tank to hold the lye, frames, a slabber or cutting table, and a press. Yet, in spite of the simplicity of thus making soap, the disadvantages are numerous for the production of a good piece of soap. The greatest difficulty is to obtain a thorough combination of oil or fat and lye so that there will not be an excess of one or the other in the finished soap. ”

“ If we gather together scrapings of lard, butter, bits of tallow from burned-out candles, scraps of waste fat, or any other sort of grease, and pour a strong solution of lye over the mass, a soft soapy substance is formed. In colonial times, every family made its own supply of soap, utilizing, for that purpose, household scraps often regarded by the housekeeper of to-day as worthless. Grease and fat were boiled with water and hardwood ashes, which are rich in lye, and from the mixture came the soft soap used by our ancestors. ”

“ Soft soap is made with potash and drying oils, either alone or mixed with tallow, and other coarse fatty matters. The fatty matter is mixed with the alkaline ley, and the whole boiled gently for some time, until the fat is completely saponified, which may be known by its becoming clear and transparent, and its susceptibility of being drawn into long threads. A quantity of common salt is then added to the boiling mixture, until the soap loses its thready character, and drops from the spatula in short thick lumps. ”

“ Several barrels of soap can be made from one ley stand. A large oil cask is good to keep soap in. If a barrel leaks, set it under a spout in a rain, or fill it with water. It is of the greatest importance to keep the soap-fat in strong ley. Have an oil barrel in the cellar, half full of strong ley, and put in cracklings, bacon skins, pot skimmings, beef bones, or any scraps, when eaten by ley it will take but little boiling. It is much the easiest and safest way, where there are children, to make the soap without boiling. ”

“ When lye and grease are boiled together, they form soap. You cannot very well make soap in the laboratory now, as the measurements must be exact and you need a good deal of strong lye to make it in a quantity large enough to use. But the fact that soap is made with oil, fat, or grease boiled with lye, or caustic soda, which is almost the same thing, shows why a soap must be 99-44/100% pure, or something like that, if it is not to injure "the most delicate fabric." ”

“ Shaving Soaps and Creams are made either with soda or potash, of fine tallow or cocoanut oil, which has the property of making a strong lather. Mottled Soaps owe their variegations of color to the use of iron oxides. It is said that these cannot be effectively applied if the soap contains an excess of water, and that more skill is required to make good blue mottled soap than any other. The more any soap is worked over, or remelted, cooled, etc., the better it becomes. ”

“ CHAPTER XIII. Soap, Candles, Tallow Tree, Spermaceti, Wax, Mahogany, Indian Rubber or Caoutchouc, Sponge, Coral, Lime, Carbon, Oxygen, Nitrogen, Gas, Hydrogen, Chalk, and Marble.
Of what is Soap composed?
Of soda or potash, and various oily substances; it is so useful for domestic and other purposes, that it may be regarded as one of the necessaries of life; immense quantities of it are consumed in all civilized countries. Soft soap is generally made of a lye of wood-ashes and quicklime, boiled up with tallow or oil; common household soap of soda and tallow, or of potash and tallow ”

“ Soft water is better than hard for fabrics.
What Soaps Are Made Of. Common Yellow Bar Soap contains soda with fat and rosin. White Soap consists of tallow and soda. Castile Soap is made of olive oil and soda. Common Fancy Soaps are mainly ordinary soap colored and scented. Real Brown Windsor Soap is made of goat tallow, olive oil and soda. Transparent Soaps are those which have been dissolved in alcohol. Fine Toilet Soaps are made with as little alkali as possible, of almond, palm or olive oil, suet, lard, etc., colored and perfumed. ”

“ As soap is everywhere used for washing at present, a question arises what substitutes were employed before it was invented. Those with which I am acquainted I shall mention and endeavour to illustrate. They are all still used, though not in general; and they are all of a soapy nature, or at least have the same effects as soap; so that we may say the ancients used soap without knowing it.
Our soap is produced by a mixture of lixivious salts and tallow, by which means the latter becomes soluble in water. ”

“ Effects of Strong Soap on Fabrics. Soap must not be strong enough to injure fabrics or discharge colors, yet sufficiently powerful to render grease and dirt soluble, so that it may be washed away in water. Rosin soap hardens the fibers of wool, and alkalies, if used to excess, shrink woolen fabrics. 54Hard water, or that containing lime or magnesia, more or less decomposes soap, and it floats on the surface as a greasy scum. But if an oily film rises to the top of soft water, it shows that the fat in the soap is not all saponified. ”

“ Settled rosin soaps are made from tallow, grease, cottonseed oil, bleached palm oils of the lower grades, corn oil, soya bean oil, arachis oil, distilled garbage grease, cottonseed foots or fatty acids together with an addition of rosin, varying from 24 per cent. to 60 per cent. of the fatty acids which should titer from 28 to 35. A titer lower than 28 will prevent the finished kettle of soap from being capable of later taking up the filling materials. As has already been stated under hardened oils, these being very much higher in titer allow a greater percentage of rosin to be added. ”

“ Unsaponifiable Matter.—The usual method adopted is to saponify about 5 grammes of the fat or oil with 50 c.c. of approximately N/2 alcoholic potash solution by boiling under a reflux condenser with frequent agitation for about 1 hour. The solution is then evaporated to dryness in a porcelain basin over a steam or water-bath, and the resultant soap dissolved in about 200 c.c. hot water. When sufficiently cool, the soap solution is transferred to a separating funnel, 50 c.c. of ether added, the whole well shaken, and allowed to rest. ”

“ Two tons of tallow should yield three tons of white soap. In making the same quantity of common brown or yellow soap, twelve hundred weight less is required, on account of the substitution of that amount of yellow rosin.
17. The mottled appearance of some soaps is caused by dispersing the ley through it, towards the close of the operation, or by adding a quantity of sulphate of iron, indigo, or the oxide of manganese. Castile soap, now manufactured in the greatest perfection at Marseilles, in France, receives its beautifully marbled appearance from the sulphate of iron. ”

“ The Krebitz process which has been used to some extent in Europe is based upon the conversion of the fat or oil into lime soap which is transformed into the soda soap by the addition of sodium carbonate. To carry out the process a convenient batch of, say, 10,000 pounds of fat or oil, is run into a shallow kettle containing 1,200 to 1,400 pounds of lime [Pg 124] previously slaked with 3,700 to 4,500 pounds of water. The mass is slowly heated with live steam to almost boiling until an emulsion is obtained. The tank is then covered and allowed to stand about 12 hours. ”

“ Besides being useful for wheel lubricating, leather-dressing, candle-making, and a variety of other useful purposes, fat can, by proper treatment, be made available as the principal ingredient in the manufacture of soap. Soap, to prepare. Some care and management, however, are required to manufacture a really good and useful article. Sir Samuel Baker thus writes of his experiences in the matter: “Soap-boiling is not so easy as may be imagined. It requires not only much attention, but the quality is dependent upon the proper mixture of the alkalies. ”

“ Soap is a very important product to every branch of the textile industry. For woolen fabrics it is used for scouring, fulling and throwing the wool; in the silk industry it is necessary for degumming the raw silk, as well as for dyeing; in the cotton mills it is used to finish cotton cloth and to some extent in bleaching; it is, furthermore, employed in a number of ways in the manufacture of linen. Large quantities of soap are thus consumed in an industry of so great an extent and the requirements necessitate different soaps for the different operations. ”

“ Tablet or Washer Type.—A demand has arisen for soap of free lathering qualities, which has become very popular for general household use. This soap is usually made from a mixture of cotton-seed oil, tallow, and cocoa-nut oil, with a varying amount of rosin. The tallow yields firmness and durability whilst the other constituents all assist in the more ready production of a copious lather. ”

“ After the leys are put in, add the tallow, and light the fire. When all the tallow is melted, put in the oil, and draw the fire a little afterwards, and allow the pan to stand about two hours. Light again the fire, and add about 20 gallons more of the leys. After the pan begins to boil, add now and then a little more leys, to the purpose of preventing the soap from boiling over: and this adding of lees to be continued until the soap is supposed to be about half boiled; when it will be time to try, whether the soap has got too much, or too little leys. ”

“ It is really a question to what use a soap is to be put, and at what price it may be sold. There is, of course, a difference in the appearance, form and color, and then there are soaps of special kinds, such as floating soaps, transparent soaps, liquid soaps, etc., yet in the ultimate sense they are closely allied, because they are all the same chemical compound, varying only in their being a potash or soda soap, and in the fatty acids which enter into combination with these alkalis. ”

“ Curd Soaps.—Tallow is largely used in the manufacture of white curd soaps, but cocoa-nut oil sometimes enters into their composition.
The first three operations above described, viz., pasting, graining out, and boiling on strength, are proceeded with; the clear boiling by means of a closed steam coil is continued until the "head" is boiled out and the soap is free from froth. A sample taken and cooled should be hard. ”

“ The tallow and grease are first saponified as usual, then the cocoanut oil is pumped and saponified. When the saponification is nearly completed either silicate or carbonate of soda or common salt are added to make the soap "short" so as to form the mottle. The finishing of a soap of this type can only be gained by practice and it is rather difficult to explain the exact appearance of the kettle at this stage. The surface of the soap should be bright and lustrous with the steam [Pg 82] escaping in numerous places in rose-like formation. ”

“ The efficiency of soap depends upon the fact that in the presence of an abundance of water the saponified fat is decomposed into acid and basic salts, in which the impurities of the skin are dissolved and are washed away by the further application of water. Good soap exerts its effects on the outer layer of the skin, the so-called horny (epithelial) layer, which in soapy water swells up and is, in fact, partially dissolved in the medium and washed away. This fact, however, is unimportant, since the superficial skin cells are reproduced with extraordinary rapidity and ease. ”