Apr., 1915
T H E JOURNAL OF I N D U S T R I A L A N D ENGINEERING CHEMISTRY
CONTRIBUTIONS OF THE CHEPIST TO THE LEATHER INDUSTRY By WILLIAMH.
TEAS
President Marion Extract Company
Although one of the most ancient of industries, and involving as it does chemical reactions, the leather industry has, in only comparatively recent years, received the attention of chemists. The record of the accomplishments of the chemist in this industry during the past twenty-five years will comprise most of the advance along chemical lines that has taken place in the industry. The advent of the chemist in the leather industry was induced by desire to effect economies in raw materials; research, and improvement in methods became a secondary effect of the chemist’s presence in the tannery, but success in the primary effort for economy was responsible for secondary effects, and for the now very general custom of laboratory control of the tannery. The leather industry is divided into general divisions of vegetable and mineral tannages, and each of these has been subdivided into many specialized industries developed by the product demanded, and the use of the raw material suited to the product. In general, the tanning agents used, the oils, greases, finishes, etc., have in themselves been the chemists’ fields, and in these and in the methods of application the chemists have found their work. The chemist has indicated improvements in the soaking and preliminary preparation of the raw skins, so that a saving of the costly hide substance has resulted; his work in selecting the proper depilating materials, and in improving methods of their application has resulted in economy and in improved products. Practically all of the progress in deliming hides by the use of special preparations has been accomplished by the chemist; and to him is also due full credit for the results of investigations of the influence of the character of the water supply on the tanning operations. The utilization of by-products in this preliminary stage of tanning is another branch of effort in which the chemist has demonstrated his value. In vegetable tanning, the chemist has improved the methods of leaching the raw tanning materials so that more of the tannic acid content has been made available; his laboratory work has shown the reasons for many of the rule-of-thumb methods of the practical tanner, and thereby afforded a means of anticipating and correcting conditions which would produce an unsatisfactory product. The standardization of tan-liquors, with the consequent tendency toward uniformity of product, could not have been accomplished without the work of the laboratory. The utilization of spent tan liquors formerly run to the sewer, by pdrifying and concentrating into a thick extract for mechanical tanning, is also a laboratory development; and the chemist is responsible for the progress so far.made in the sewage disposal problems of the tanner. The chemist has materially aided in the work of replacing the fast diminishing native barks, with combinations in proper proportions of foreign tanning materials, foreign and domestic extracts, so that physical characteristics and quality the leather produced under the new conditions is similar to the old product. The standardization of leather oils, greases and waxes, and the protection of the tanner against adulteration is a matter of course with any laboratory, but the standardization and protection was badly needed in the leather industry, and the accomplishment of the chemist in this line is fully credited. The development of special oils for leather work, especially sulfonated oils, and the application of the oils to remedy certain defects in leather, is due to the chemist; he is also responsible for special combinations of waxes and greases for stuffing leathers according to the requirements of the use t o which the leather is put. The development of the mineral tannages has been due almost entirely to the chemist; the chrome process was first suggested
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by a chemist and later its development to a commercial success was accomplished by a chemist. Ever since chrome tanning was started in a commercial way, the modifications of process and materials, tending to economy and improvement, have been due to chemists, so that one of the greatest accomplishments of the chemist in the leather industry, has been the process by which most of the light leathers of the world are tanned. The successful lubrication of the fiber of chrome-tanned leather has meant much to the utility and consequent popularity of chrome leather, and by means of saponifiable and so-called “soluble oils” the chemist has materially helped in this important factor. Other mineral tannages, and tannages by formaldehyde and other aldehydes, have been worked out by chemists and brought to more or less commercial success as a result of laboratory work, Combinations of mineral and vegetable tannages for the production of leathers for certain purposes, are also the work of the chemist. Synthetic tannins, or a t least products which give reactions analogous to the natural tannins, have been introduced by chemists, and their commercial value in some lines of the industry has already been demonstrated. In the manufacture of tanning extracts from raw materials which grow in localities distant from the tannery locations, chemists have played an important part. Clarification processes introduced by them have, in some instances, increased the availability of some tanning materials, which, without clarification, would have a diminished economic value. Credit is also due the chemist for the production of special extracts, which have made possible the saving of time and labor in the production of certain kinds of leather. In the production of patent and enameled leathers, of fancy leathers, and in the field of dyeing and coloring so important to light leathers, and in the numerous other departments of tanning, not mechanical, which space will not permit of particularizing, the chemist has been and is an important factor in product improvement. The chemist in the leather industry has had to overcome the prejudice of the practical tanner against tanning theory, and without guiding precedents has been obliged to make his own standards, and develop his own ground work. Recognition of the value of the efforts of the chemists is evidenced in the vast increase in the number of tannery chemists during the past twenty-five years. And still further evidence is the establishment of a tanning school in which chemistry is the most featured branch in the curriculum; and also the definite plans for starting a national rFsearch laboratory to be supported by the industry, and to be devoted to research work in the chemistry of tanning. MARION,VIRGINIA
CONTRIBUTIONS OF THE CHEMIST TO THE FLOUR INDUSTRY By
JOHN A. WESSNERAND GEo.
L. TELLER
Consulting Chemists
Flour may be defined as the fine white meal of the interior of the wheat grain, either by itself or mixed with a small proportion of finely ground wheat bran or wheat germ. Its quality depends upon the kind of wheat from which it is made and upon its freedom from bran and germ, which for the most part in the ordinary process of milling find their way into coarse by-products ordinarily sold as feed for domestic animals. There are several types of wheat recognized in this country, the most clearly defined groups of which are soft winter wheat, hard winter wheat, spring wheat, durum wheat. There are many gradations between the first two of these classes and sometimes it is difficult to distinguish one from the other: both also include distinctly different types of wheat. The leading types of hard winter wheat are found in Kansas and Nebraska: the leading soft winter wheat section is in the Ohio Valley and
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