The farmer and mechanic., 1915-06-22

done more toward broadening the
culture of the world than printers
ink Printed matter is to be found
everywhere, and one OF its great
values has been the education OF the
foreigner come to another land. Yet
despite its universal use there are few
who know the different materials
used OF realize the processes required
to prepare ink for printing.
A new exhibit i'm the Division Of
Graphic Arts of the u. S. National
Museum, located in the Smithsonian
building at Washington, well illus
trates the several different processes
and shows the many ingredients in
the making Of printers ink. 1t starts
with the raw products, illustrates the
manufacture by photographs and dia-
grams described by labels, and shows
the finished products ready for use.
Considering our great dependence
upon this substance for daily news,
reading, records, and, in fact, all our
literature and history, the Smith
SODian exhibit offers an educational
opportunity not to be neglected.
The manufacture of modern print
ing ink requires a careful choice of
materials and their very skillful
manipulation. The materials fall into
two groups, the pigment Or color, and
the medium or varnish in which it is
ground. The varnish is prepared from
liIseed oil and rosin, but while lin
seed oil is the most satisfactory
medium, cheaper ones such as rOSln
oil and even mineral oil are used.
Various gums and wakes are en-
plOyed to give a greater consistency.
The drying quality is increased by the
a ,f fnl1 ,Ie,f- h bi,o
tend to make the oil in the ink Oxi-
die. This INK does not dry in the
common sense, by evaporation, but
passes through a chemical change
which leaves totally different sub
stance. The varnish holds the color
pigments together, and makes pos
sible their mechanical manipulation
on the presses, lending luminosity and
added richness to the colOrs.
In preparing the varnish the oil is
first boiled and burned until it ar
rINes at the proper consistency when
the rosin is stirred in. The pigment
is added and the mass ground to an
impalpable fneness. OF course, every
manufacturer has his own methods
and trade secrets, which is Cnly to be
expected when it is realized what
great care and precision the printing
ink maker has to exercise. Such ar
ink must have free distribution
leaving the work clear and sharp with
no oil on the paper; it must not ad-
here too tenaciouSly to the types bu
leave them clean, and must at th<
same time dry quickly on the paper
hut not on the rollers; besides which
il must be proof against the effect O
time.
In the manufacture of the commOi
black ink, lampblack and carbon
black are the most common pigments
They are really the same thing, tha
is. finely divided carbon, but diffe
in the process of manufacture. Some
times a little indigo or Prussian blu
is also employed with the carbon. Fo
wood engraving carbon and ivor
black, or a very fine bone blac
known as Frankfort black, are mixed
In photographic reproductions Pari
black is used.
The ingredients in colored inks in
C'ude some chemically made color.
such as vermillion, Prussian or bronz
blue, chrome yellow, and ultramarin
blue. The lake" pigments. made b
preCipitating a coal-tar dyeStuff o
metallic base, produce colorS
greater brilliancy and extreme fine
ness of texture. Natural earth colo,
are not used so much as fOrmerl,
their shades being now matched
the lake" colors.
Red ink is made with carmine {
CCchineal and in cheap inks, red lea
but it rapidly blackors and is cons'
quently unsuitable for permanel
work. Blue inks are made from ind
go or Prussian blue; yellow with lea
ChrOmate or yellow ochre; green ar
purple by mixing yellow and blu
and red and blue respectively.
The only white ink sufficient
Opaque to appear white on a da,
surface is made from white lea
Tints and light tones of the vario,
COiOrs are made by mixing the colo
with zinc white or another transpa
en-: base such as magnesia or bla1
fxe.
Ink making machinery consists
several types of mixing machines wi
which the medium and dry color a
FIRST roughly mixed together, and mi
on which the mass is thorough
ground. The type of machine us
IL. hn oh>r ~ of f1n