THE KESENES OF RESINS AND OLEORESINS* 



By Chas. H. Herty and W. S. Dickson 



The oleoresinous exudate of pine trees, commonly called 

 " crude turpentine," consists of a mixture of a volatile oil, acids 

 and unsaponifiable matter. On distillation with steam the 

 volatile oil, "spirits of turpentine," passes off; the residual 

 resin, freed from excess of water by heating, solidifies on cooling 

 and constitutes commercial " rosin." The name " resene" has 

 been applied by Tschirch^ to the non-volatile, unsaponifiable 



^ Tschirch, " Die Harze und die Harzbehaeter," Second edition, p. 1079. 



constituent of such resins and oleoresins. 



Though the composition of crude turpentine varies consider- 

 ably in different specimens, an average analysis of specimens 

 collected by the usual commercial methods would show approx- 

 imately : * 



Per cent. 



Spirits of turpentine 20 



Acids 74 



Resene, 6 



Resenes, according to their origin, show varying physical 

 states, some being colorless solids while many are very viscous 

 liquids, extremely sticky and non-crystallizable. They are com- 

 posed of carbon, hydrogen and oxygen, but the per cent, of 

 oxygen is usually smaller than in the accompanying acids. 

 Toward reagents they are very resistant, especially toward alka- 

 lies. Although containing oxygen, they show, according to 

 Tschirch,^ none of the usual reactions indicating the presence 

 of hydroxyl, carboxyl, aldehyde or ketone oxygen, nor are they 

 ethereal salts or lactones. Tschirch inclines to the view that 

 they belong to the class of exyterpenes or oxypolyterpenes. 



While much work has been done upon the volatile oils and the 

 acids of oleoresins, little attention has been paid to the resenes, 

 except ultimate analyses and approximate statements of the pro- 

 portion present in isolated specimens studied. In connection 



* Reprinted from the Journal of Industrial and Engineering Chemistry, Vol. IV, 

 No. 7, July, 1912. 

 ^Loc. cit. 



