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Let's briefly talk about the advantages and disadvantages of the five most common materials for eyeglass frames:
1. Metal eyeglass frames. Metal eyeglass frames can be divided into three categories: copper alloy, nickel alloy and precious metal. Eyeglass frames made of these rare metals have better hardness, can withstand strong impact, and have better corrosion resistance than other materials. However, metal eyeglass frames have average texture, poor toughness and elasticity, and are more likely to slip when exposed to sweat.
Double bridge square metal sunglasses DS481 gold front side
2. Plate eyeglass frames. Plate is currently the most popular material for eyeglass frames and is also the most widely used material for eyeglass frames. Compared with other material eyeglass frames, it is not easily corroded by sweat and salt water, and is not easy to rust. It is the best corrosion-resistant material for eyeglass frames. Moreover, the polished plate has high gloss, is translucent, and has a soft texture, which is suitable for all skin types.
3. Plastic eyeglass frames. The biggest advantage of plastic eyeglass frames is that they have one of the best corrosion resistance. Moreover, its sun protection and environmental protection are also loved by many consumers, and the material is extremely light, which is generally lighter than ordinary plate eyeglass frames. The sports performance is also better, which allows you to experience a unique and relaxing experience. The price of plastic glasses is generally low, and the colors are relatively simple.
4. Titanium frames. Titanium is available in two types: pure titanium and mixed titanium. It is about 48% lighter than metal frames, and is more comfortable to wear without any signs of squeezing the skin. Titanium frames are hard, not easy to be scratched, and not easy to damage. They are the most durable glasses frame material. Moreover, they will not rust, have a good affinity with the skin, and will not cause any skin allergies.
Dual color cateye titanium eyeglass frame DS473 front view
5. TR90 glasses frames. TR90 is a high-tech material. The glasses frames made of it are half the weight of the plate, ultra-light and ultra-thin, and have strong weather resistance, high temperature resistance, and are not easy to deform or break. They are the most suitable glasses frame material for strenuous exercise. The disadvantage is that the style, structure, and color of TR90 glasses frames are relatively simple. 
 
How to identify a good pair of glasses and a bad pair of glasses. 
Everyone basically understands the advantages and disadvantages of glasses frames made of different materials and how to identify them. Maybe you are now concerned about how to identify the quality of a pair of glasses. This may be what everyone cares about most. Maybe you will say, don't be long-winded, just tell me how to identify the good and bad. Don't worry, you don't understand some basic engine principles and basic knowledge such as speed and impact. How do you identify a good car and why it is good? I will tell you how to identify the quality of glasses. In general, there are three main factors that determine the quality of glasses: material, process details, and shape.
 
Glasses material: We just talked about the material, you can refer to the above content. Now I will tell you about other aspects.
 
Glasses hinge: The hinge is like a person's joint, and its importance is self-evident. Although glasses are not high-tech products, details should still be taken seriously. Using high-quality hinges is like a person with strong and flexible joints. High-quality products generally use better hinges, such as Comotec in Italy and OBE hinges in Germany. Kanghua is a relatively good domestic company, and the various hinges produced by some hinge factories in Shenzhen are also of good quality. High-quality hinges are generally equipped with rubber screws. How to judge the quality of hinges, first from the appearance, second from the function. The appearance is smooth, without pitting, and the lines on the edges are neat, indicating that the craftsmanship is relatively good and the precision is high. The force is uniform when opening and closing, and it is smooth and without jamming. The service life of high-quality metal hinges is generally more than 10,000 times, while some inferior ones may become loose or have problems such as screws falling off after a period of use.
 
Glasses nose pads: The nose pads of metal glasses are generally installed separately, and there are transparent PVC, silicone, or titanium. The quality of nose pads is generally distinguished from several aspects such as comfort, stability and durability. Good nose pads are reasonably designed to adapt to different nose shapes and are comfortable to wear. For example, the teardrop nose pad is comfortable and can be adjusted up and down 20~40 degrees, and left and right 10~30 degrees to adapt to various nose shapes. At the same time, high-quality nose pads are stable and not easy to slide or fall off. Another is durability. Good nose pad materials are durable and not easy to age. For example, pure titanium nose pads can be used for many years and are not easy to age. In general, one is to look at the surface and workmanship details, and the other is to look at the function and comfort. In addition, the nose pads of plastic glasses and plate glasses are generally connected and mostly transparent. Comfort is one of the best evaluation methods.
 
Electroplating spraying: It refers to metal frames, which need to be electroplated with color and sprayed. The quality of this process also determines the quality of the frame. Appearance inspection is one of the most basic methods to evaluate the quality of the spraying process. The quality of the spraying quality can be judged by observing the flatness, glossiness, color of the sprayed surface and whether there are bubbles, cracks, peeling, pitting and other defects on the coating surface with the naked eye. Another is to look at the hardness. Use a hard object to scratch it slightly to see if there is any coating falling off or scars. Corrosion resistance is one of the important evaluation criteria for the quality of spraying process, but it is difficult for ordinary consumers to pass the naked eye test. Factories that produce high-quality glasses will pass some professional tests before leaving the factory. Salt spray test and sweat test are the two most common tests. High-quality frames must pass salt spray and sweat tests for at least 48 hours. Therefore, it is also important to choose a good brand of glasses when buying.
 
Glasses screws: There are usually 2 to 4 small screws for glasses, hinges and nose pads. If it is a mixed glasses frame, there will be more screws to connect and fix different parts. The quality of the screws can be judged by the surface, and the hinge screws also depend on the function. The screws with excellent craftsmanship have a flat and smooth surface and clear edge lines. The hinge screws also depend on the function, and the hinges are stable and smooth when opening and closing. Of course, if allowed, you can also take out the hinge screws to see if there is a rubber cover on the screw column, which is usually black rubber, to increase the stability and service life of the hinge. Excellent hinge screws can be used more than 10,000 times without any damage. Therefore, screws are also very important. Bad screws may even rust, affecting the appearance and health.
 
Silk screen printing or laser engraving: refers to the logo or data on the glasses, mainly including paint pad printing, laser engraving, hot stamping, UP stickers, etc. Now these processes are very mature and basically will not fade. The quality is mainly determined by the surface, whether the font is clear, whether there are burrs on the edges of the pattern and font, whether the surface is smooth, etc. For the paint pad printing process, if allowed, you can use your fingernails to gently scratch it to see if there are scars or discoloration.
 
Glasses lenses. At this time, it mainly refers to sun lenses, because the lenses of optical frames need to be replaced according to consumer needs. Sun lenses are one of the most important accessories for sunglasses. The materials of sun lenses are mainly CR39, nylon, PC, TR and other materials. The material and process costs of CR39 and nylon are relatively high, and the transparency is also the best. To judge the quality of sun lenses, one is to look at the surface, and the other is to look at the function. Check whether the surface of the lens is smooth, whether there are bumps, scratches or bubbles; observe whether the two lenses are symmetrical, and observe whether the surrounding straight lines are bent or swaying through the lenses; feel whether the temples and nose pads fit the face when wearing. Second, look at the function, and the ability to block ultraviolet rays is the key. The lens or packaging should have UV400, 100% UV protection, UV protection and other labels. These labels indicate that the lens can block more than 99% of ultraviolet rays. Sunglasses without these labels may not effectively block ultraviolet rays and may damage the eyes. For some sunglass lenses with color films, you can check whether they have anti-oil and waterproof effects. The simplest way is to draw lightly on them with an oil pen. If the oil-proof effect is good, it will be gone with a light wipe of the lens cloth. The waterproof effect is the same. Water dripped on it will automatically condense into water droplets, which will be gone with a light wipe.
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