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VISCOSITIES SLOWING YOU UP?
blankets, saddle pads, or warm-up bandages, M r . Fitz is all for trying. Grooms may never learn to call it polyurethane, but they agree that there is something to be said for a durable and all-but-weightless material, unaffected by acids, alcohols, and liniments, that can be washed and re-used again and again. " N o point of hanging on to the old way of doing things, just because it is the old way," so says M r . Fitz, who is approaching his 86th birthday.
SEDIMENTATION GETTING YOU I DOWN?
Colored Diamonds
If high viscosity is slowing your processing of an aqueous slurry, try adding a Marasperse® dispersant. Or if your customers complain of sedimentation when they mix your product with water, put a Marasperse in your formulation. Only a little Marasperse is needed to reduce slurry viscosities, or to prevent micron-sized particles from settling out of suspensions. Usually less than 3%, based on the weight of the solids in the aqueous system, will do the job for you. For example, manufacturers of gypsum board require just 0.15% Marasperse in their stucco slurries to give them more fluidity at lower water contents . . . And producers of pesticide wettable powders include but 1.5% to 2.0% Marasperse in their powders to ensure satisfactory dispersion in spray tanks. What's more, the Marasperses cost only a few cents a pound! Tell us about your viscosity or suspensibility problem. If it's typical of one of the many that the Marasperse dispersants have licked, we'll give you specific information based on user experience. If it's something new or unique, we'll tell you how to test samples of the Marasperses to determine whether or not they'll be useful to you.
M A R A T H O N QÉQ A Division
of
A m e r i c a n Can Company CHEMICAL SALES DEPARTMENT MENASHA, W I S C O N S I N
MARATHON · CHEMICAL
A D i v i s i o n of A m e r i c a n SALES
DEPT. ·
Please send Information File N o . 1-110 Q
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Can Co.
MENASHA, WIS.
Samples •
of MARASPERSE f o r use in
NAME TITLE COMPANY. ADDRESS.... "lease
attach
to
your company
letterhead.
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42 A
INDUSTRIAL A N D ENGINEERING CHEMISTRY
REPORTS
IB#IAMONDS are generally considered to be clear crystals. But since 1900 almost everyone has devised a coloring technique, largely based on radiation and exposure to modestly high temperatures. For the last 60 years it has been a real snap to make yellow, or brown-green crystals with 10-hour radium irradiation treatments. They have also been made brownred, brown, or brown-green with 1200-hour irradiation. These coloring methods are generally conceded to be results of complex Frenkel defects. It is now possible by using radiation and higher temperature to produce a single Frenkel defect in the actual diamond lattice. This produces a pure blue color which is more than a surface effect and cannot be removed by polishing or grinding. In the past, alpha particles have been responsible for the surface color change, but it is now possible to use gamma rays. Energies of about one million electron volts and above with an integrated flux of about 10 to 20 gamma rays per sq. cm. are used. Several years' irradiation would, however, be required to obtain this flux from known gamma rays sources such as cobalt 60 or a Van der Graaf machine with a suitable target. Now that new techniques have been developed from radiation, no telling what may be done with cheaper starting materials.
