US7880A - Improvement in manufacture of india-rubber - Google Patents

Description

- UNITED STATES ATENT OFF CE.

J. T. TROTTER, OF NEW YORK, N. -Y.

IMPROVEMENT IN MANUFACTURE OF INDIA-RUBBER.

Specification forming part of Letters Patent No. 7,880, dated January 1, 1851.

To all whom it may concern Be it known that L'JONATHAN T. TRoTTER, of the city, county, and State of New York, have invented a new and useful and Improved Process for Curing or Preparing or Vulcanizing India-Rubber; anti I do hereby declare the following to be a full and exact description of the same.

The nature of my invention consists in the new and useful manner in which I prepare the rubber by means of an article or preparation of zinc. The process for preparing the said zinc article is as follows:

In a solution of caustic lime, potash, or any other caustic alkali l boil flowers of sulphur till the liquor is completely saturated. In making tlns lyc l have the alkali alwa s in excess. After the boiling of the liquor it is removed from the fire and allowed to stand and cool, when any excess of sulphur in the lquor settles to the bottom, lea\ing a cear sulphureted-potash solution. This clear liquor is then decanted intoanother vessel, in which is a concentrated solution of the sulphateof zinc. On the mixture of these two solutions a decomposition takes place, and the zinc is precipitated in the form of a white powder, which may be calleda bisulphuret ofzinc, or artificial preparation of zinc of similar characteristics chemically combined. When the zinc has all been precipitated it is collected and washed and filtered, and then exposed to dry, after which it is ground in an ordinary grinding-mill till'it becomes an impalpnble powder. It is in this state mixed and ground with the indie-rubber, in the ordinary mills used for that purpose, in the proportion of about four pounds of the preparation of zinc to about ten pounds of the rubber, and the coinposition, after being subjected to a heat for about three to five hours to a temperature of 250 to 280 Fahrenheit, according to the thickness of the material and the purposes to which it is to be applied, isfound to be completely cured or vulcanized, and without the use of free raw sulphur in any way in combination with the rubber.

As a new and useful compound material for curing india-rubber, it is superior to all other known processes, except my hyposulphite-ofzinc process, which formed a part of the series of experiments resulting in this improvement. It has none of the otfeusiveness of sulphur goods, because raw sulphur is not used in any way in combination with the rubber. In consequence of this disuse of raw sulphur in any way with the rubber, they never have to be boiled in a potash liquor, as all other rubbercured goods have to be. The advantage of this is that the texture of the rubber is not atfected; second, my process admits of making up on all kinds of fancy silk or uoolen fabrics, wnile with other curing, processes animal textile tabrics and tancy-colored goods would be destroyed by the alkali-boiling: process, which lasts from four to six hours; third. my process save timeandlaboriucuring rubberbythesulphur process. Atter coming from the potashboiling they require to be sun-dried, artificial heat not being suflicient to remove the peculiar stickyorclnmmyteelingaboutthem. Thissundry lug takes several days when not good drying-weather and never less than two days. Other advantages could be enumerated, but deem it not necessary, sutfioient having been pointed out to show the value and importance of my improved process of curing rubber, samples otwhich accompany this specification.

Having described my improved process tor curing rubber, I will state what 1 claim and desire to secure by Letters Patent.

What I claim, therefore, is-- The use and employment of zinc,,substantially as prepared by the process above described, in combination with india-rubbcr, for the purpose of curing or vulcanizing it, in form and manner as herein set forth, without the use of free sulphur in any way in combination with the rubber.

JONA. T. TROTTER.

Witnesses CHARLES L. BARRITT, JOHN S'rURGEs.