2024 Author: Howard Calhoun | [email protected]. Last modified: 2023-12-17 10:16
Rosin is an amorphous, brittle substance with a vitreous structure and color from light yellow to dark red. It is obtained after distillation of the volatile component from the resins of coniferous trees. The chemical properties of rosin (up to 90% of resin acids, including the main one - abietic) make it insoluble in water, but soluble in ethers, alcohol, chloroform and benzene. When heated to 50-120 C (for different varieties), rosin bars soften.
Where did the word "rosin" come from? This is most likely a distorted name of the ancient Greek city of Colophon, around which trees grew, giving such a substance. In ancient times (more than three thousand years ago), turpentine was obtained from resins by heating, and the dry residue was just a primitive rosin substance.
Rosin is an accessory without which you cannot play, for example, the violin, viola, double bass, cello. When rubbing the bow with a piece of this substance, free molecules are formed, which give a certain adhesion tostring, which contributes to the extraction of sound. Such rosin is often produced in a non-industrial way from resins collected exclusively in the fall with the addition of “secret” ingredients that each company has its own (metal, silver and even gold dust, etc. can be added). In addition, rosin used to be rubbed on the soles before sports, for example, wrestlers, as well as the saddles of jockeys before the races.
Rosin is a substance that has been widely used and is used in industry. In former times, it was in demand in soap making, the production of plasters, sealing wax. Today, compounds with rosin are used to fasten glass components of lamps to bases, for the production of varnishes, in printing work, in soldering industries, and also in the paper industry. And everywhere its main property is used - the ability to create sticky compounds when heated.
The production of rosin in general terms has not changed in millennia. The source material (tarred stumps, collected resin - resin) is placed in cubes, where it is steamed or heated on fire. About 12 kg of turpentine (distilled off) and 70 kg of rosin are obtained from a centner of resin, which is boiled down to remove liquid and placed in containers. If the substance is extracted from the stumps, then they are pre-crushed, and then the mixture of wood chips and water is subjected to the extraction process. About forty kilograms of rosin can be obtained from one cubic meter of tarred wood.
What are the main regulations used by businesses that produce rosin? GOST No. 19113 - 84, in particular, contains the basic requirements for products and a number of production parameters. From it we can find out what the appearance of rosin should be, what is the permissible density, water content, softening point, acid number, etc. The document also indicates the requirements for the safety of the production process (rosin is a moderately hazardous substance, because its aerosol can cause irritation), acceptance rules, methods of analysis of the finished product, storage rules and warranties.
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