The reason for the crystallization of nano liquid coating is due to the high purity of silicon dioxide, because the purity of silicon dioxide in the nano coating liquid is high enough, with the contact with the air will automatically oxidize into crystals. Silicon dioxide, is an inorganic compound, silicon atoms and oxygen atoms long range orderly arrangement to form crystalline silicon dioxide, short-range ordered or long-range disordered arrangement to form amorphous silicon dioxide. Silicon dioxide crystals, silicon atoms are located in the center of the orthotetrahedron, four oxygen atoms are located in the four top corners of the orthotetrahedron, many of these tetrahedrons and through the top corners of the oxygen atoms are connected to each oxygen atom for the two tetrahedrons **** there, that is, each oxygen atom is combined with two silicon atoms.