TYRES—RUBBER OR ZINC

Shannon News, 5 October 1928, Page 4

TYRES—RUBBER OR ZINC

Few realise that the ordinary highelass automobile tyre contains many other things besides rubber. Zinc oxide for instance, is used in greater tonnage than any other compounding ingredient* for rubber, not alone because it is an excellent w-hite pigment, but also because it reinforces rubber compounds with relatively little sacrifice to their resiliency. The rubber used in tyres must, of course, be reinforced in some way, for pure rubber, while resilient, will not stand wear and tear of • he road.

The rubber tread of the average size solid tyre weighing about 1001 b. is composed of 341 b. of first-quality rubber IMb. cotton, 411 b carbon black, and 59 lbs. of zinc oxide. Zinc oxide also fills an important place in the modern giant pneumatic bus tyres and in the regular passenger “balloon' tyres. While our tyres are generally spoken of as rubber tyres they arc in fact composed only of about 50 per cent, rubber. The remainder of the tyre is composed of materials to cure the rubber, increase its wear, and protect it from injury. ———————————^—