Both inorganic material or organic material made of glasses, in daily use, due to dust or sand (silica) can cause friction wear lenses, the lens surface scratches. Compared with glass,
Rigid organic materials is relatively low, more prone to scratches. Through the microscope, we can observe scratches the surface of the lens is divided into two kinds, one is generated as gravel scratches, light and small, wearing glasses is not easy to detect; the other is generated by the larger grit scratches , deep and rough around, in the central region will affect the vision.
Anti-wear film began in the early 1970s, when that is not easy to grind glass lenses because of its high hardness, and organic lens is too soft so easy to wear. Therefore, the quartz in the vacuum deposited on the surface of the organic lens, Zinc oxide forming a layer of very hard wear-resistant film, but because of its thermal expansion coefficient and film-based materials do not match, it is easy stripping and film embrittlement, so anti- wear and tear are not ideal.
After the 1980s, researchers have theoretically found that the mechanism of wear is not only related with the hardness, the film material has a "hardness / deformation" of the double feature that some material hardness, but the deformation is smaller than some hardness is low, Titanium dioxide but large deformation. The second generation of anti-wear process by soaking membrane technology is the organic law on the one kind of lens surface coating of high hardness and less brittle material.
The third generation of anti-wear film technology since the 1990s developed, mainly to solve the organic anti-reflection lens coating film on the wear resistance after the issue. As the organic base of the lens film hardness and the hardness of anti-reflection film is very different, the new theory is needed between the two anti-wear coating layer, so that the lens in the gravel by the friction when acting as a buffer, and not prone to scratches. The third-generation anti-wear coating material hardness between antireflection coating and the hardness of the lens between the film base, and its low coefficient of friction and less brittle.
The fourth generation of anti-membrane technology is the use of a silicon atom, such as France's emperor Essilor plated Adams (TITUS) Hard solution containing both the organic matrix, but also include silicon containing ultrafine particles of inorganic material, Nickel oxide the anti-wear films toughness also increased with the hardness. Modern anti-wear coating membrane technology is most important is the use of immersion, that is the lens through multi-channel cleaned, immersed in liquid and hard, after a certain time, to bring a certain speed. The speed and the viscosity of the fluid and hard, and against the wear and tear film thickness play a decisive role. Filed after the 100 ° C oven for about 4-5 hours in the aggregate, the coating thickness of 3-5 microns. Source: