This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1920 Excerpt: ...(boiling point 160 C.) was found of high wetting value but had a somewhat too rapid evaporative value. Furthermore it acted rapidly as a solvent for certain lakes. Carbon tetrachloride was found too volatile. Linseed and similar fatty oils were too immobile and did not show sufficiently high wetting value for quick ...
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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1920 Excerpt: ...(boiling point 160 C.) was found of high wetting value but had a somewhat too rapid evaporative value. Furthermore it acted rapidly as a solvent for certain lakes. Carbon tetrachloride was found too volatile. Linseed and similar fatty oils were too immobile and did not show sufficiently high wetting value for quick determination?. The investigation finally showed that water-white kerosene was the best medium. Accordingly several gallons were obtained and allowed to settle to throw down any small amounts of water present. The kerosene was subsequently filtered and kept in five-gallon bottles. The method finally developed is given below. It should be pointed out that this method gives slightly lower bulking figures than methods in which the pigments are not dried or in which air is not removed. METHOD DEVELOPED AND STANDARDIZED 1. Standardization Of Pyknometers.--Fill the pyknometers with freshly boiled distilled water and bring to temperature of 15.6 C. Dry and weigh as outlined in paragraph 6. Clean, weigh and dry the pyknometers. Fill them with the kerosene to be used and bring to temperature of 15.6 C. Dry and weigh in the same manner. Calculate the specific gravity of the kerosene by dividing the weight of water into the weight of kerosene. 2. Drying.--Dry the pigment in an oven, preferably electric, at 105 C. for 2 hours. 3. Weighing.--Weigh a sample of the pigment, by difference, in the weighing bottle. For blacks, blues and lakes of light specific gravity, use about 1 gram; for inert crystalline pigments about 4 grams; for opaque white pigments 7 to 10 grams; for red lead 15-20 grams. Due to the hygroscopic nature of some of the pigments it is necessary to use a weighing bottle fitted with a cork stopper. 4. Transferring To Pyknometer.--Pour sufficien...
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