US2109416A - Rosin for violin bows, etc. - Google Patents

Description

Patented Feb. 22, 1938 UNITED STATES PATENT OFFICE ROSIN FOR VIOLIN BOWS, ETC.

Emanuel Dziemczyk, Breslau-Goldschmieden,

* Germany 3 Claims.

This invention relates to a process of producing rosin for treating violin bows, etc.

The invention is based on the knowledge that in order to obtain rosin particularly well suited 5 for treating violin bows, etc., hard resin or colophony must be reduced to dust or meal from which a solid body is then formed by pressing or the addition of a suitable binding agent. Pressed rosin of this kind is superior in use to the hard resin or colophony commonly employed for the purpose. For example, while a new and fully washed out bow must be passed about 150 times to and fro over a piece of colophony of the usual type to become completely saturated therewith, only about 25 applications of the new pressed rosin are necessary to obtain the same effect. Subsequent rubbing of the bows is correspondingly facilitated, so that a considerable saving in time and labor is effected and the bow hair is carefully preserved. Another advantage is that the rosin according to the invention is distributed much more finely and evenly over the bow hair than is the hard resin now employed. Furthermore, the new rosin can be more thoroughly utilized, as its fine particles are uniformly removed from the surface of the piece or cake, whereas the hitherto employed. colophony, as a rule, is worn to form a hollow in the center of the piece due to the strokes of the bow, so that the lateral portions of the piece were usually thrown away without having been used. The new rosin makes possible not only the formation at will of cakes having varying fineness of the particles thereof but, in addition, permits regulation of the degree of solidity of the piece by more or less pressing thereof during manufacture and thus meets requirements as to the composition and hardness of the rosin within very wide limits.

A further valuable property of the new rosin is that it is unaffected by atmospheric influences, so that its particles will come 01f equally well at any time, which does not occur in the case of the known hard resins.

Rosin according to the invention is produced by subjecting commercial colophony to grinding, pulverizing, pressing 'or other suitable operations 5 to reduce it to dust or meal. The mass thus obtained is then made into a solid body either by mechanical action, such as the exertion of pressure, or by the addition of a suitable binding agent which either merely mixes with the 10 dust or forms a chemical compound therewith.

A particularly appropriate mechanical treatment consists in compressing the colophony dust by placing it in a tubular die and subjecting it to the action of a press ram until the particles 15 thereof are combined into a solid body of desired hardness and solidity. The sticky nature of the fine particles of colophony dust considerably facilitates the attainment of the purpose aimed at.

In this manner rosin pieces of any desired cross 20 sectional form and height can be produced. For preparing larger quantities; it is advisable to employ a deep die and to subdivide the rod of rosin thus obtained into pieces of desired size by sawing or cutting. To facilitate the removal of the 25 pressed rosin from the die the latter preferably is of circular cross section.

I claim:- 7

1. Rosin for violin bows or the like, comprising a compact unitary mass composed of individual 30 mutually adhering particles of powdered colophony.

2. Rosin for violin bows or'the like, comprising a compact unitary mass composed of individual mutually adhering particles of powdered 0010- 35 phony and a small amount of a binding agent.

3. Rosin for violin bows or the like, comprising a compact unitary mass composed of individual mutually adhering and substantially unfused particles of powdered colophony. 40 V EMANUEL DZIEMCZYK.