There are many kinds of plastic materials used in the manufacture of frame, which can be divided into sheet metal and ejection forming:
As a whole, the difference between the frame and the shot frame is that the frame does not fade and is not easy to break; the shape of the shot frame changes greatly and has a sense of three-dimensional; the plate and frame are mainly artificial, and the treatment of the shot frame is much worse. The relative manufacturing cost of sheet metal frame is much higher than that of ejection frame.
Science and technology continue to progress, and more new materials appear; but so far, there is no material, the glasses frame can be said to be perfect, because the mirror frame requirements are:
(1) Good toughness (comfortable and not easily broken);
(2) Sufficient hardness (no deformation);
(3) Heat (about 70-100℃) can be concentrated (easy to install lenses);
(4) Good affinity for dyeing and coloring (easy processing and dyeing, not easy to fade);
(5) Heat resistance (anti-burning);
(6) Good corrosion resistance (not to be corroded by sweat acid or oil);
(7) Do not irritate the skin.
