UNITED STATES DEPARTMENT OF AGRICULTURE 



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1 BULLETIN No. 855 



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Contribution from the Bureau of Animal Industry 

 JOHN R. MOHLER, Chief 



Washington, D. C. 



PROFESSIONAL PAPER 



May 6, 1920 



SAPONIFIED CRESOL SOLUTIONS 



By Jacob M. Schaffer, Junior Chemist, Biochemic Division 



CONTENTS 



Properties of mixtures with rosin soap. 

 Observations on speed of dilution 



Cost of materials used . 

 Summary 



This paper describes a series of experiments undertaken with the 

 object of preparing a saponified cresol solution which would be 

 cheaper and at the same time no less effective as a disinfectant than 

 those at present in use. Such a product should contain the usual 50 

 per cent cresol with the necessary quantity of soap to insure complete 

 solubility in water and should meet the following requirements: 



The product shall remain a homogeneous liquid when cooled to 32° F. It shall 

 contain substantially no free oil, fatty acid, or excess alkali. It shall be readily 

 soluble in cold distilled water; the solution shall be practically clear and shall contain 

 no globules of undissolved oil or cresylic acid. 1 



By stating the qualifications of a good finished product the Bureau 

 of Animal Industry has safeguarded itself and at the same time 

 allowed the manufacturer to mix the necessary ingredients in the 

 manner he finds most economical. 



Disinfectants made with cresylic acid and rosin soap have been 

 objected to because they become cloudy when diluted with water. 

 In the case of a cresol-rosin soap solution diluted with water to a 

 3 per cent solution and exposed in a flask to the air, it has been found 

 that the clouding is due to the hydrolysis of the rosin soap and the 

 absorption of carbon dioxid from the air, the rosin being precipitated 

 at first in finely divided particles. After a few days these particles 

 commence to agglomerate and settle to the bottom; finally, after 

 about two weeks, equilibrium is reached, the solution clears, and 

 shows a good deal of rosin in a mass at the bottom of the 



171564°— 20 



i U. S. Bureau of Animal Industry Order 263. 



