enterprise
After more than 50 years of development, China's insulation material industry has initially formed an industrial system with relatively complete products, complete supporting facilities, and considerable production scale and scientific research strength. Especially in the past 20 years, the varieties of insulation materials have developed rapidly, the quality has been greatly improved, and the product level has reached a new height.
Until the 20th century, insulation materials were basically made from natural materials or their products. The first electric motors were insulated with silk, cotton, and cotton. In order to improve water resistance, shellac and other natural resins are used to impregnate with vegetable oil and asphalt.
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