1060
T H E JOURNAL OF INDUSTRIAL AND EIiGINEERIING CHEMISTRY
keeping the beaker wvered and maintaining a volume of approximately 50 cc. by frequent additions of water. Filter immediately into a 250-cc. beaker and wash the residue several times with hot water. Dilute the filtrate to 75 or 100 cc. and add 7 cc. of concentrated sulfuric acid and a sheet of alumiuium. Boil until all the copper has been precipitated. Cool rapidly with the aluminium strip in the solution, keeping the beaker covered. ,Fdter iiito the original beaker, wash well with cold water, dilute to 3ijo cc. with cold water and titrate
Val. 14, No. 11
at once to a pink color with a standard solution of potassium permanganate. Calculate the per cent of iron. This represents the amount of metallic iron in the sample. In this titration the potassium permanganate may be replaced by potassium dichromate, using potassium ferricyanide as an external indicator. This method has been found reliable in the routine analysis of a large number of sponge iron samples whose metallic iron content varied from 0.5 to 90 per cent.
Some New Sensitizers for t h e Deep R.ed’,‘ By C. E.
K. Mees and G. Gutekunst
RBS~&P.CB L & e o n ~ l ‘ o aEasru~w ~. KODAXCo., ROC~+STE., N. Y
N THE course of work extending over a number of years, many new dyes derived from quinoline have been prepared and tested for their sensitizing power. A number of compounds prepared in the course of this investigation have been described in a paper by G . Gutekunst and H. LeB. Gray on “The &Alkyloxyquinaldines.”a The purpose of the present paper is to describe three of the new sensitizers that have been seleeted as having interesting properties, two of which it is proposed to place upon the
I
market.
ACETAMNOCYANOLE ( ~ , ~ ‘ - D l E T W ~ , 6 ’ - D l A C E T A M I N O C A R ~ O C Y A N I NIODIDE) E
This dye was prepared as follows. A solution of 5 g. 6-acetaminoqninaldiueethiodide and 5 g. quinoline ethiodide in 200 cc. of boiling ethanol was treated with a mixture of 20 cc. of sodium ethylate (1 g. sodium in 50 cc. absolute ethanol) and 5 cc. of formaldehyde. A blue-green solution was formed and gt-een crystals separated on cooling. These were recrystallized from methanol.
NAPETEACYANOLE ( 1 , 1 ‘ - D I E T H Y ~ D I - 8 - N ~ E ~ O C A R B O C Y A N I NKITRATE) E
This dye was prepared as follows: A solution of 5 g. of 8-naphthoquinaldine ethiodide and 5 g. of quinoline ethiodide in 500 cc. of boiling ethanol (95 per cent) was treated with a mixture of 4 cc. Eomxddehyde (40 per cent’ and l i G cc. of 1 0 per rent alcoholic potash. Thc dye separated out in the form oi little grrcn nwJle,. wlLich on account ai their insolubiitv were runwrtcd into the nitrate. This w 3 s accomplished by &spending a small amount oi the dye in zlacial
acetic acid (75 cc.) and adding 200 cc. of 1 per cent nitric acid, iodide &tired off. The dy; was prrcipitated immediately with ammonium hydroxide and recrystallized from.methanol
Fro. ~-ACBTAP*MINOCYANOLB ZN ri~~ri.siohi
The dye obt,ained was found to sensitize powerfully when added to an emulsion, giving a maximum at 730pp. Its spectrum is s h a m in Fig. 2. When an attempt was made to use this dye in water solution for bathing plates, a very curious result was obtained, the spectrum obtained being that shown in Fig. 3 and corresponding obviously to an entirely different dye. Moreover, it was fouud that in the preparation of the dye it was necessary to be careful to keep the water content to a minimum, as otherwise thc dye had not the characteristic sensitizing maximum a t 730pp but gave a result similar to that obtained when bathing plates in water solution. The probable explanation of these anomalies is that the dye is hydrolyzed by water, the acetyl radical being
Fxo. I - , 9 - N a ~ n m ~ c u * ~ a ~ n
This dye sensitizes powerfully, both when added to the emulsion and when used for bathing ready prepared plates. A spectram shown in Fig. 1 shows a strong maximum in the deep red a t 690pp, and a sensitizing power for the green a p preciably less than that shown by pinacyanole. The dye keeps well and is quite suitable for use in the place of pinacyanole where the extreme red sensitiveness is an advantage. Received July 5 , 1922. a Commuoication No. 147 from the Research Laboratory of the Eastman Kodak- Ca.. Rcehestci. N. Y. :.I Am. . Chnn. Soc., 11 (1922), 1741 I
h o 3-Acarrm~ocunirom B A I ~ mmli ~ D
hydrolyzed off. While the dye, therefore, has some value when used for emulsions, since the plates prepared appear to keep their characteristic properties, it is not thought that it will be of general value, owing to its instability.
