38 BULLETIN" 867, U. S. DEPARTMENT OF AGRICULTURE. 



used with mineral oils as a cutting oil when no water is used. It 

 appears to have greater cooling qualities than most vegetable oils and 

 does not gum or become rancid. 



Sulphonated oils, particularly castor oil, have been used in pro- 

 ducing the dye called Turkey red. Cotton cloth is treated with alum 

 and immersed in a bath .containing a solution of sulphonated oil 

 (soluble in water). This is thought to form an aluminium oleate, 

 which acts as a mordant to form a lake. Treating the mordant cloth 

 with alizarine results in a bright red lake called Turkey red. The 

 relative quantity of this color that is now used is considerably smaller 

 than formerly, owing to the use of other colors of a similar shade. 



For mantle dips this oil, as well as other vegetable oils, is used as a 

 softener to render the coating of the mantle flexible. After the 

 mantle has been dipped the coating on it has about equal proportions 

 of cotton and the material from the oil. 



In the manufacture of linoleum, castor oil has been found to be of 

 advantage in imparting flexibility and toughness to the goods, some- 

 what the same as in imitation leather. Both No. 1 and No. 3 oils 

 have been used, but since the finished goods are usually somewhat 

 colored, no reason exists why an acid-free (refined) No. 3 oil would 

 not be perfectly satisfactory. 



Vegetable oils, notably castor oil, may be treated with sulphur and 

 vulcanized, similar to rubber. This may be effected either by treat- 

 ing the oil with sulphur chlorid or by fusing it with sulphur direct. 

 In the first case the product is known as "white substitute," due to 

 the comparatively light color of the product, while in the second 

 process the product is known as "black substitute." Sulphur chlorid 

 may be added to the oil direct in proper equipment to control the 

 temperature, or it may be added to a solution of the oil in some 

 solvent. In either case the mixture, more or less hot, may be poured 

 into molds or cooled, then ground and dried. The same treatment 

 is pursued in the case of both the black and the white products. 

 On heating, both products mix well with rubber; hence the name 

 "substitute." The role of this product does not necessarily have to 

 follow that of an adulterant in the sense that it is a mere cheapener. 

 Certain rubber goods are not satisfactory unless mixed with other 

 products. For example, the specific gravity of vulcanized oils is 

 lighter than that of rubber and their incorporation offsets the in- 

 creased weight due to mineral filler. They also impart softness to the 

 product, desirable in certain fabrication. 



It has been stated that so little sulphur chlorid is necessary for vul- 

 canizing castor oil to make it set that it is difficult to work with. 

 Some authorities state that castor oil must be used for floating 

 substitute. 



