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THE INDIA RUBBER WORLD 



[October 1, 1920. 



Toron Patents and Products' 



ALL rubber manufacturers will be interested in securing the 

 practical results claimed for the use of the patented sul- 

 phur-terpene compound known as Toron. Chief among 

 these is the increase of strength imparted by the material to 

 fiber and increased adhesion of friction to fabric treated with the 

 material; also its ability to bond firmly together metal and 

 rubber. 



The nature and method of production of this material are 

 quoted below from the patent application. 



SULPHUR-TERPENE COMPOUNDS 



It is possible to treat terpenes and certain of their derivatives 

 with sulphur to produce useful sulphur-terpene compounds. 

 When treatment is completed the product is a hard mass, soluble 

 alone or with other substances, and useful for coating surfaces 

 or impregnating and coating the fibers of absorbent materials. If 

 the chemical reaction is moderated or stopped short of com- 

 pletion, the product is more or less viscous or semi-solid, and 

 is available for use alone or in solution or in admixture with 

 other materials. 



PROCESS OF MAKING TORON 



One process, by wliich this sulphur-terpene compound can be 

 produced is thus described : 



Equal parts by weight of oil of turpentine and sulphur are 

 placed in a suitable converter, in the neck of which is fixed a 

 condenser suitably arranged to pass back into the converter the 

 products of condensation. An outlet is also provided for re- 

 moval of the gases generated during the reaction without loss of 

 the volatile constituents. The contents of the converter are 

 heated to melt the sulphur. The reaction is well determined by 

 the time a temperature of ISO degrees C. is reached. 



During the ensuing period of one hour, the temperature is 

 raised to 175 degrees C, the mass being agitated preferably with 

 air, and, during the next two hours, the temperature is raised 12.5 

 degrees C. each hour, with lessened or no agitation. During the 

 reaction, which appears to be progressive, the sulphur reacts with 

 the turpentine, partly to combine with it and partly to set hydro- 

 gen free from the turpentine in the form of hydrogen sulphide. 

 Also secondary reactions take place, resulting in removal of the 

 sulphur introduced into the terpene residue with the hydrogen of 

 the latter in the form of hydrogen sulphide, and the production of 

 char. It is because of these facts that the temperature is mod- 

 erated. 



PROPERTIES OF THE PRODUCT 



The product thus produced, when cooled to ordinary tempera- 

 tures, is a hard, brittle mass resembling mineral rubber. It 

 breaks with a fracture, showing curved surfaces presenting a 

 glassy luster. When manipulated between the fingers the ma- 

 terial becomes plastic. It is insoluble in water, partly soluble in 

 acetone, soluble in turpentine with reaction, and soluble in toluol 

 and xylol. When in solution it will pass through parchment and, 

 according to this test, is non-colloidal. 



Analysis has shown that certain of these hard sulphur-terpene 

 compounds, produced from equal parts of sulphur and turpentine, 

 as described, contain from 30 to 50 per cent of sulphur. 



When the reaction has reached the stage when free sulphur is 

 no longer present in the mass, the latter, on cooling, is a black, 

 viscous liquid. During the reaction which follows that stage, if 

 the heating is continued, the evolution of hydrogen sulphide con- 

 tinues, with increasing viscosity of the mass until charring occurs. 

 The reaction therefore may be interrupted at will, and sulphur- 

 terpene products of various characteristics and properties pro- 

 duced as desired. 



lUnitcd States patents Nos. 1.349,909 to 1,349,914, inclusive. 



The semi-solid products produced may be employed for coating 

 or impregnating various materials. For most practical purposes 

 in order to provide a quick-drying coating or impregnating 

 material it is found preferable to dissolve the hard compound in 

 loluol, xylol or their equivalent. For many purposes other sub- 

 stances may be added to the solution, such as pigments and dis- 

 solved crude or vulcanized rubber. 



APPLICATIONS OF TORON 



The practical utility of a material possessing the properties 

 exhibited by this product will be very important in the rubber 

 industry. The practical applications are covered by a series of 

 patents. 



Referring briefly to the principal functions of this material 

 in rubber goods manufacture, it has been found that cotton 

 falirics impregnated with this product are not only preserved from 





Sections of Toron Pneumatic and Solid Tires 



deteriorations but gain very markedly in tensile strength. When 

 such impregnated fabrics are friction-coated the penetration and 

 adhesion of the rubber composition are much superior to those 

 obtained without the chemical impregnation. This is due to the 

 lact that the sulphur-terpene compound by vulcanization unites 

 with rubber so that contiguous layers of rubber and fabric 

 cannot be stripped apart at their juncture. 



This feature constitutes a distinct advantage over present prac- 

 tice in the manufacture of every variety of rubber goods con- 

 taining fabric such as tires, hose, belting, boots, shoes, etc. 



As a bonding material to unite rubber to iron it is particularly 

 effective for the manufacture of rubber-covered press rolls or 

 solid tires. The metal is first surfaced with a solution of the 

 sulphur-terpene material, upon which are built several plies of 

 toronized, frictional fabric and the tread composition. The sul- 

 phur-terpene compound and the rubber-sulphur compound react 

 and vulcanize together and bond solidly to the metal. 



In explanation of the union of rubber to metal the theory is 

 offered that the sulphur-terpene compound in contact with the 

 iron, excludes the possibility of surface oxidation, and that the 

 sulphur-terpene compound interacts with the iron to form a 

 sulphur-iron compound, which not only furnishes a protective 

 coating on the iron surface, but also acts as a bond between the 

 iron and the .siilplnir-rubber compound. 



SYRINGA VULCANINE 



A new organic accelerator known as Syringa Vulcanine is 

 being supplied to the rubber trade of Great Britain and conti- 

 nental countries by the English manufacturers. It is a special 

 drug which enhances toughness and durability without decreas- 

 ing the resiliency of the cured product. It has been proved of 

 especial benefit in the manufacture of tire treads, rubber heels, 

 etc. It is claimed also as an equalizer of vulcanization, requiring 

 less sulphur and obtaining more uniform results. 



