April 1. 1913.] 



THE INDIA RUBBER WORLD 



383 



GROSS LICHTERFELDE MATERIAL TESTING 

 BUREAU. 



By Our Regular CorrL'jpoiiJeiit. 



' I 'HE iinnual ruport of the Gross-Lichterfelde Material Testing 



* Bureau, dealing with the year ending March 31, 1912, 



records the work of the establishment in various branches of 



testing, including rubber, both crude and manufactured. 



Among the samples tested was one of crude rubber, respecting 

 which it was desired to ascertain whether it was really Ilez'ca, 

 so far as this point could be ascertained by the known process. 

 The test made showed 2.1 per cent, of components soluble in 

 acetone, which were almost completely saponiliable, but did not 

 display optical activity. On the basis of these facts it could be 

 stated that tlic sample was probably of Hcvca. 



Another sample of rubber was to be tested for loss in washing, 

 which exceeded 20 per cent. As, however, the sample had been 

 shipped during the hottest season and in a bag which admitted 

 water, the report called attention to the fact that a considerable 

 portion of tlie wafer must have been taken up on the way and 

 in storage. 



Numerous tests were made of technical ruliber goods, sucli as 

 hose, etc., with the object of ascertaining their chemical com- 

 position. Samples of balloon material in the unused as well 

 as used state were subjected to comparative chemical investiga- 

 tion. From the results of the analyses it was to be determined 

 whether the destruction of the used material was produced by 

 the gas used in tilling the balloon or not. The analyses only dis- 

 played slight differences in the chemical composition of the two 

 samples. The changes noticed corresi)ondcd with those which 

 might in practice be expected from the influence of air, light and 

 mechanical causes (apart from that of the gas). 

 VULCANIZATION. 



The large number of vulcanization tests had showed that 

 physical absorption was combined with a chemical reaction of 

 the sulphur with the rubber. The former occurs in a moment, 

 while the latter often takes a considerable time. Vulcanization 

 can take place at any temperature, even at a normal degree, but 

 its speed varies with the temperature. 



CRUDE AND VULCANIZED RUBBER. 

 The analyses of vulcanized and crude rubber included in the 

 first place different forms of the bromide process. In this way 

 a number of sources of error were discovered. Consequently, for 

 determining the rubber content of crude rubber or rubber com- 

 pounds it is necessary to resort to indirect analysis. That is, the 

 other components are defined and the difference between their 

 total and 100 per cent, is assumed to be rubber. 



DEVELOPMENT OF GERMAN COLONIES. 



In a retrospect of the past six years in the German colonies. 

 Dr. Wohltmann, editor of the "Tropenpflanzer," advocates the 

 importance of training young German agriculturists, both 

 theoretically and practically, with a view of utilizing their 

 knowledge and experience for the benefit of the German colo- 

 nies. The number of such students is annually increasing. 

 Such has been the policy of the German government since 1907. 



Respecting the prospective rubber supplies from the German 

 colonies, the author remarks : 



"Only the next few years will afford us a reliable idea of 

 how much good rubber is to be obtained from our colonies. On 

 the one hand, the best methods of cultivation, tapping and col- 

 lecting, are the subject of much discussion ; while on the other 

 hand, the trees planted in East Africa and Kamerun are in part 

 so young, or have been in bearing so short a time, that an in- 

 disputable prognosis cannot be made. * * * It is today 

 certain that the results of our plantations will not be unfavor- 

 able. What yields and profits they will show in the future, we 

 must wait to see." 



THE JAPANESE WASTE RUBBER AND RECLAIMED 

 RUBBER TRADES. 



li\l Our Regular Corrcspottdciil. 

 \Y7.\.ST1-- rubber is supplied to Japanese consumers from 

 two sources, domestic collection and imports. In the 

 former shape it is gathered by ragpickers, who go from door 

 to door in search of various kinds of waste, including waste 

 paper and rags. Each broad class of waste is then handled 

 by houses in the particular branch. Thus waste rubber 

 passes through the hands of waste rubber dealers. Waste 

 rubber is also obtained in more or less miportant quantities 

 through tenders made to the naval and military administra- 

 tions and large industrial corporations. 



Another source of waste rubber is the purchase of old cycle 

 and motor car tires from dealers in those articles. 



Imports of waste rubber are from Shanghai and other 

 points, representing an average of $1,500 a month. Such im- 

 ports take place when Japanese waste is scarce or dear. The 

 latter is, however, in most cases, preferred by the Japanese 

 rubber manufacturers. Waste is sorted into black, red and 

 white; in each class there lieing superior, medium and in- 

 ferior grades. 



The quantity of waste rubber produced in Jaijan is estimat- 

 ed at about 2 million pounds, and tlie value at about $200,000. 

 Black waste is in the largest quantity and varies in price from 

 .S to 15 cents per pound. The production and consumption of 

 Japanese waste rubber are alike increasing at the rate of 20 

 per cent, annually. Most of the waste rubber produced was 

 originally of Japanese manufacture. Tokyo is the principal 

 center of the Japanese waste rubber trade, the waste being 

 shipped thither from Osaka and other points, for eventual 

 distribution among the principal cities of Japan. 



RECLAIMED RUBBER-^JAPANESE .\ND IMPORTED. 



At one time Japanese rubber manufacturers used to mix 

 waste rubber with crude rubber, in order to cheapen their 

 product. The waste, after being mixed with certain ingre- 

 dients, was brought into an unsulphurized state by mixing it on 

 a roll with certain ingredients. This compound was desig- 

 nated as "reclaimed rubber" by Japanese manufacturers and 

 used for the production of molded goods, such as "tabi" soles, 

 tubes, tires, etc., either alone or in conjunction with crude 

 rubber. 



Reclaimed rubber, properly so called, is not produced in 

 Japan, but is imported to the extent of about 15 tons a month. 

 It is principally consumed by several insulated wire makers, 

 who must have the genuine imported reclaimed rubber, as 

 they cannot use the Japanese article; although the latter can 

 be used for the manufacture of other goods, such as molded 

 articles. The efforts made to get copper wire wrapped or 

 tubed in thin sheets of the Japanese so-called "reclaimed rub- 

 ber" have been unsuccessful. The imported reclaimed rubber 

 principally comes from England and the United States. 



DUTY ON IMPORTED RECLAIMED RUBBER. 



The Japanese duty on reclaimed rubber is 20 per cent., 

 while the article is free of duty in England, the United States, 

 Austria. Italy, Denmark, Xorway and China. Several years- 

 ago there was no duty in Japan, but a duty of 10 per cent, 

 was imposed to meet the case of the Dunlop Rubber Co. (Far 

 East), importing free of duty as "reclaimed rubber," a com- 

 pound, the ingredients of which in some cases paid 5 to 20 

 per cent. Under the new Japanese tariff it was made dutiabia 

 at 20 per cent. Waste rubber was still retained on the free 

 list as being of benefit to Japanese manufacturers, but re- 

 claimed rubber was treated as a manufacture of waste, at the 

 lowest rate applicable to manufactured rubber. 



Efforts are being made to get the duty reduced to 10 per 

 cent., in which the correspondent of The Indi.\ Rubber World 

 is taking an active part. This rate has met with the approval 



