The color - coated steel substrate is cold - rolled substrate, hot - galvanized substrate and plating substrate. Coating types can be divided into polylipids, silicone modified polylipids, polyurethane and plastic sol. Colorized painting steel plate surface state can be divided into coating, embossing and printing plate, belt, steel is widely used in building electrical appliances and transportation industries, for the construction industry is mainly used in steel structure factory building, airports, warehouses and refrigeration industries and rhinoceros top wall and door of commercial buildings, civil construction is made of color steel plate less. It differs from plastic steel in the composition of the material, the magnet can absorb movement.In a strict sense, plastic steel and color steel in the metal characteristics and surface treatment can not be very good distinction, because much the same;Now the market is mainly divided in the section structure.· because it is a common carbon steel material, the magnet can absorb iron. In addition, the stainless steel is the product of adding chromium element on the basis of low carbon rigidity (the dry length is equal to 13%), so the iron sucker cannot absorb. You cannot use a magnet to prove that the material contains no iron.In the late 1980s, China began to build color steel plate units, most of which were built in steel mills and joint ventures. By 2005, China's color steel plate reached 1.73 million tons, resulting in overcapacity.State-owned large iron and steel enterprises such as baosteel, anshan iron and steel, benxi steel, shougang, tangshan steel, handan, wuhan, jinan, kunming, PZH steel companies such as the unit capacity, equipment level is higher, have built using foreign technology, annual production capacity of 120000 ~ 170000 tons of choi steel unit.