plastics: Materials that can beshaped by applying heat or pressure.Most plastics are made from polymericsynthetic resins, although afew are based on natural substances(e.g. cellulose derivatives or shellac).They fall into two main classes. Thermoplasticmaterials can be repeatedlysoftened by heating and hardenedagain on cooling. Thermosetting materialsare initially soft, but change irreversiblyto a hard rigid form onheating. Plastics contain the syntheticresin mixed with such additivesas pigments, plasticizers (toimprove flexibility), antioxidants andother stabilizers, and fillers. SeeChronology overleaf.
일반 설명
Error limits according to class A, DIN EN ISO 1042. Calibrated to contain (TC, In). Exposure to temperatures up to 121 °C (autoclaving) will not cause permanently exceeded error limits! Cleaning up to max. 60 °C is recommended to preserve marks and inscriptions.
공업 용도
Plastics are a major group of materials that are primarily noncrystalline hydrocarbon substances composed of large molecular chains whose major element is carbon. The three terms plastics, polymers, and resins are sometimes used interchangeably to identify these materials. However, the term plastics has now come to be the commonly used designation. The first commercial plastic, Celluloid, was developed in 1868 to replace ivory for billiard balls. Phenolic plastics, developed by Baekeland and named Bakelite after him, were introduced around the turn of the century. A plastic material, as defined by the Society of the Plastics Industry, is any one of a large group of materials consisting wholly or in part of combinations of carbon with oxygen, hydrogen, nitrogen, and other organic and inorganic elements which, while solid in the finished state, at some stage in its manufacture is made liquid, and thus capable of being formed into various shapes, most usually through the application, either singly or together, of heat and pressure.
