Plastic eyewear frames have a traditional negative image in some people’s mind. There are some conventional drawbacks associated with plastic sunglasses and eyeglasses. For example, these frames are more fragile than metal frames under external impact. Even if they are not easily ignited, plastic frames may burn after a long period of sunlight exposure. In addition, long-term sunlight exposure may also lead to a decrease in frame strength. Well, it is possible to point out a couple of other reports on plastic frames’ shortcomings. An opposite side is that metal sunglasses are prevailing. Titanium, stainless steel, aluminum and memory metal have been widely used to make eyeglass and sunglass frames. And it seems that these advanced forms of metals tend to replace gradually those traditional plastics. But the current fact is that plastic frames and metal frames develop generally in parallel.

The current status or proportion maintained by plastic sunglasses in this market is well founded. And most people may suppose that plastic sunwear frames have their own features or advantages. This is the emphasis of this article. It is the plastics’ natural properties that help these materials maintain their popularity in lots of industries including the eyewear industry. The first priority should be given to lightness, which is an attribute claimed by nearly all types of plastics, varying from zyl, cellulose acetate propionate to nylon. This feature or advantage is a common place among all plastics. Sunglasses are usually used in an outdoor environment. Lightness is an important contribution, especially to performance or sports sunglasses. It is true that metals like titanium, beryllium, stainless steel and aluminum also claim lightness. However, they are lightweight only compared with traditional metals like iron, bronze or gold. Plastics are unbeatable in this aspect.

Another point that helps plastics gain the current status in the sunwear industry is their flexibility in color application. Plastic sunglasses can be easily found in various colors like green, orange, red, purple and any other. In contrast, metal sunglasses are generally disappointing in color provisioning. The reason is that plastics are easier to be tinted than metals. In regular, colors are applied to the surface of plastics or metals. Yet most plastics also allow a color mix-up in them.

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