solvents and diluents	189
materials, including some cellulose derivatives. Prolonged exposure to the vapor
affects the blood, producing both anaemia and leucopenia, the symptoms being
headache and general lassitude, and if exposure is excessive, it leads to delirium
and final death (see Hamilton, pp. 156—165).
Benzine (petroleum spirit). This name is now being discarded because of its
confusion with benzene, a coal-tar product. It is still given to a volatile petroleum
distillate similar to gasoline. At times the word is applied indiscriminately to
various petroleum fractions below kerosene.
Benzol is the commercial name for the coal-tar distillate, Benzene, containing
also toluene and other benzene homologues.
n-Butyl Acetate (CH_3COOC_4H_9). One of the recent developments of the solvent
industry, this ester of butyl alcohol and acetic acid is a clear, stable liquid with
strong ethereal odor. When pure, it boils at I26.5°C., but the commercial product
is only about 85 per cent pure. Unlike the lower esters, it is not hygroscopic and,
hence, does not hydrolyze and become acid. It mixes in all proportions with ben-
zene and many other organic solvents, but is only slightly miscible with water.
The solvent action is strong on cellulose nitrate, other cellulose plastics, and syn-
thetic resins. The low rate of evaporation prevents blush and gives a good flow
to such mixtures. In the lacquer industry it has largely displaced amyl acetate.
The vapors are not toxic. Secondary butyl acetate and isobutyl acetate, prepared
from isomers of butyl alcohol, are also available commercially, and their properties
are little different from those of the normal acetate.
n-Butyl Alcohol (butanol £C_4H_9OEQ) may be prepared in four isomeric forms,
but the normal alcohol is the most important. The Weizmann process brought it
out on a commercial scale during the war of 1914—1918 when it was derived as a
by-product of acetone in the fermentation of corn mash by a specially developed
bacillus. Somewhat later its value as a lacquer solvent was recognized and its
production became the chief purpose of the Weizmann process. It is separated
from the other solvents, acetone, ethyl alcohol, higher alcohols, and fatty acids,
and is purified by distillation. Little has been done to record experimentally its
action on the film materials of artists* paint and varnish. Very limited observations
make it seem that the solvent properties of butyl alcohol are somewhat stronger
than those of ethyl alcohol.
It is not miscible with water in all proportions but only to the extent of 7.7
per cent at 2o°C. and mixes with most organic solvents. It is able, moreover, to
promote miscibility in other mixtures like that of benzene, petroleum naphtha,
and ethyl alcohol. Commercially, it is said to have a good solvent action on hard
copal and on shellac. Its boiling range is 110° to 118°C. It evaporates at a moderate
rate, is not hygroscopic, and, since it does not incline towards blush, is a favorite
solvent for synthetic lacquers. It is said to be a good solvent for metallo-organic
driers like lead and cobalt linoleates, and to have an effective solvent action on
linoxyn and other oxidized oil films. The vapors of butyl alcohol are distressing