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T H E J O U R N A L OF I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y
quantities of the respective elements yet it is evident in a number of cases t h a t the quantity of plant food carried t o a soil by the irrigation water is sufficient t o assist in maintaining the fertility, for it is quite certain t h a t where the waters are rationally used the quantity of potassium, phosphorus, or nitrogen carried t o the soil exceeds t h a t removed in the drain waters. UTAHAGRICULTURAL COLLEGE LOGAN,UTAH
A NEW YELLOW DYE AND LIGHT FILTERS MADE FROM IT By C.
E. K. MEEs
AND H. T. CLARKE Received January 2, 1919
Vol.
11,
No. 5
became pressing, and we undertook a search for such a material. After a great number of trials i t was found t h a t suitable absorption and stability were possessed by the phenylglucosazones. When certain sugars, such as glucose, are warmed with a solution of phenylhydrazine in dilute acetic acid, yellow precipitates are produced possessing definite crystalline structures, by which the sugars may be characterized. These yellow substances are known as osazones, those formed with phenylhydrazine being termed phenylosazones. On measurement of the absorption spectrum of glucose phenylosazone i t was found t h a t the absorption curve was very sharp and extended far into the ultraviolet, and since the material is known t o be stable, it appeared t h a t a dye prepared from it would possess the properties required for the preparation of light yellow filters.
I n the early days of orthochromatic photography the dye generally used for the preparation of light filters was picric acid, this having the advantage of simplicity and cheapness and of great efficiency, picric acid absorbing the ultraviolet almost completely, and having a very sharp cut in the spectrum. The disadvantage of picric acid, however, is t h a t i t is unstable t o light, filters made with it soon turning brown. For this reason the early gelatin filters were made chiefly with tartrazine, which is very stable and gives permanent filters. Tartrazine, however, has the disadvantage t h a t its absorption in the ultraviolet is unsatisfactory and even moderately deep tartrazine filters transmit appreciable amounts of ultraviolet, thus detracting very much from their efficiency. For FIG.2 this reason filter yellow, introduced by Hoechst in 1907, Glucose phenylosazone is insoluble in water so t h a t rapidly displaced tartrazine as the best dye for filter t o obtain a dye it is necessary t o have a salt-forming making and has held t h a t position ever since. group present in the molecule, and t o produce a dye suitable for use with gelatin, it is desirable t h a t this EASTMAN Y€LLOW c o x m o group should be an acid one. To obtain such a derivative of glucose phenylosazone which will form salts with metals, it is merely necessary to substitute for phenylhydrazine a derivative containing an acid group, and condense glucose with i t in the same manner. Several such derivatives were tried and the most satisfactory result was obtained with glucose phenylosazone-p-carboxylic acid. This was prepared in the following way: p-Nitrotoluene was oxidized t o give p-nitrobenzoic acid. This was then reduced t o p-aminobenzoic acid, which was diazotized and gave p-hydrazinobenzoic 300 400 500 acid or phenylhydrazine-p-carboxylicacid. The glir-FIG.1 cosazone of this acid is a yellow crystalline compound Filter yellow is extremely stable, absorbs the-ultra- insoluble in water and almost insoluble in alcohol. violet strongly with the exception of a transmission It forms a sodium salt which is extremely soluble in band a t 300p,u, which, since i t is absorbed by glass, water but which can be precipitated from concentrated is of little importance, and has a satisfactorily sharp solutions by the addition of alcohol, and this sodium cut for the preparation of orthochromatic filters. A salt of glucose phenylosazone-p-car boxylic acid has been disadvantage of filter yellow, which has always been adopted by us for the preparation of light filters under recognized, however, is the fact t h a t its absorption the name of “Eastman Yellow.” curve is less sharp than t h a t of picric acid, and for many I n Fig. I are shown the absorption spectra of tarpurposes, especially the preparation of very light fil- trazine, filter yellow, and Eastman yellow, from which ters, a dye possessing the stability and ultraviolet ab- it will be seen t h a t the Eaotman yellow has a sharper sorption of filter yellow but of greater sharpness of cut than filter yellow and as strong an absorption in cut would be desirable. the ultraviolet. When the need arose for light filters of high efficiency Light filters prepared from it retain these characfor aerial photography the necessity for such a dye teristics, and these ligllt filters have been prepared
May, 1919
T H E J O U R N A L OF I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y
aqd specified under the names of E K - I and EK-2 light filters. A special filter for adrial photography has been adopted b y t h e American forces under the name of Aero No. I . Fig. 2 shows the absorption curves of these light filters. As regards stability, i t was found on test t h a t the new dye was not quite so stable t o light as filter yellow but was superior t o all other yellow dyes tried and its stability is amply sufficient for the preparation of light filters since i t requires weeks of exposure t o direct sunlight t o produce a change even in the lighter colored filters. RESEARCH LABORATORY EABTMAN KODAK COMPANY ROCHESTER. N. Y.
PARA CYMENE. II-THE UTILIZATION OF CYMENE FOR THE PREPARATION OF PHOTOGRAPHIC DEVELOPERS’ By HERBERT A. LUES Received February 24, 1919
For some time this laboratory has been engaged in a study of cymene and its derivatives with the idea not only of preparing new derivatives of cymene, b u t also improving t h e methods of preparation of those already known and the development of their possible commercial application. Two of the more extensively used photographic developers are p-aminophenol and quinol (hydroquinone). Similar substances can be prepared from cymene, and are described in the literature, but their commercial applications in photography have apparently not been investigated. Both p-aminocarvacrol and thymoquinol can be obtained from carvacrol. The preparation of p-aminocarvacrol is relati’vely simple and a fairly good yield is secured. The patent recently granted t o McKee2 on the preparation of carvacrol from cymene seems t o make possible t h e development of a n abundant source of supply of this phenol, which hitherto was prepared only in small amounts. The process of McKee3 involves the sulfonation of cymene and a subsequent alkaline fusion of the sulfonic acid. T h e preparation of a phenol on a small laboratory scale by such a method is usually not very satisfactory because of the poor yield from t h e alkaline fusion. T h e . writer has found t h a t a yield of 85 t o g o per cent of carvacrol can be obtained by diazotizing aminocymene, dropping the cold diazo solution into dilute sulfuric acid and simultaneously steam-distilling. This is a very satisfactory laboratory method for the preparation of carvacrol. The 2aminocymene can be obtained in good yields by a method described in the first paper on 9-cymene. p-AMINOCARVACROL Tests of this compound showed it t o be a very promising photographic developer.4 Comparisons of “Para Cymene. I-Nitration, MonoGtrocymene,” THIS JOURNAL, 10 (1918). 453. 2 U. S. Patent 1,265,800, May 14, 1918. THIS JOURNAL, 10 (1918), 982. 4 Tests were made by H. A. Piper of the Science and Research Department, Bureau of Aircraft Production, since the photographic research of that organization was handled in this laboratory.
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monomethyl p-aminophenol (commercially known as metol), p-aminophenol, and p-aminocresol with paminocarvacrol were so favorable t o the last-named as t o warrant a detailed investigation of its properties. The preliminary results indicate t h a t p-aminocarvacrol is more satisfactory than p-aminophenol, but not quite so good as p-aminocresol or “metol,” so far as lasting quality of the bath is concerned, but equally good with respect t o quality of tones secured in the finished prints. METHOD OF PREPARATIoN-p-Aminocarvacrol, CH8
0
-OH,
HzN
was prepared by reducing p-nitro-
I
C3H7
socarvacrol by means of ammonium sulfide. For the laboratory preparation of p-nitrosocarvacrol the method of Klagesl is quite satisfactory. The following description is essentially the procedure of Klages, with slight modifications. Ten grams of carvacrol are dissolved in 40 g. of alcohol, saturated with hydrochloric acid gas a t oo. T o the cooled solution add a n aqueous solution of 5 g . of sodium nitrite in I O cc. of water. Before addition, the nitrite solution is diluted with an equal volume of alcohol. I n a few minutes the solution becomes a pasty mass. This is dilute with water, filtered, and washed. The crude nitrosocarvacrol thus obtained is not further purified but used in this form. REDUCTION-The crude nitrosocarvacrol is dissolved in about I O times its weight of I O per cent ammonia and filtered from the tar. A rapid stream of hydrogen sulfide is passed into the ammoniacal solution and the aminocarvacrol is precipitated as practically colorless leaves. The solution is then cooled and filtered, the precipitate dried with suction, washed with cold water, and dried in a vacuum desiccator over sulfuric acid. I n case i t is necessary, the aminocarvacrol can be recrystallized by boiling with hot water t o which animal charcoal has been added, filtering and cooling the solution. To prepare the hydrochloride, which is much more soluble in water t h a n the free base, the aminocarvacrol is suspended in a small amount of water and about t h e theoretical amount of hydrochloric acid added. The solution is heated and filtered while hot. To the hot solution concentrated hydrochloric acid is added until a precipitate begins t o form. When the crystallization is completed by cooling the solution, the hydrochloride is removed by filtration, and dried in vacuo a t 75‘. From I O g. of carvacrol about 5 g. of aminocarvacrol in quite a pure condition were usually obtained. CHa
I
Thymoquinol,
(---OH, HO-J
I
C~HT 1 Ber..
38 (1889), 1518.
was
prepared by
