In the early 1980s, scientists proposed the concept that silicon-containing hydrogel is an ideal material for contact lenses, because silicon is a known oxygen-permeable material with high oxygen permeability, which is not easy to cause hypoxia and dry eye, and will not cause changes in the number of corneal endothelial cells. However, silicon materials are extremely hydrophobic and difficult to mix with hydrophilic materials, so it is difficult to make biocompatible silicon hydrogel materials. After nearly 20 years of continuous research and development of soft contact lens products with high oxygen permeability, although silicone hydrogel contact lens materials are intended to solve the problem of oxygen permeability, they are incompatible with or unacceptable to the eye due to their low surface wettability.

The wettability of the contact lens surface is large, and the tear film formed is uniform and stable. The uniform and stable tear film is a necessary condition for comfortable wearing, ideal vision and preventing the formation of precipitates. If there is too much sediment on the lens, the hydrophilicity and oxygen permeability of the lens surface will decrease rapidly. In addition, there is a very thin lipid layer on the surface of normal tears, which is used to prevent tears from evaporating too quickly.

After wearing contact lenses, because of the lens material, contact lenses will compete with tears for water, this lipid layer will not adhere to the surface of tears as stably as before, and the evaporation of tears will naturally accelerate, which indicates that the material must contain water. The moisture content of contact lenses is very important. Moisture content can help increase oxygen permeability and bring softness, but at the same time, moisture content of more than 60% will compete for moisture in the eyeball.

Internationally, in the past 20 years, the first and second generation of silicone hydrogel contact lenses have been trying to solve the problems of surface wettability and water content of silicone hydrogel contact lenses. It was not until the third generation of silicone hydrogel contact lenses appeared that the problem was fundamentally solved.

The third generation silicone hydrogel contact lens material of pharnorcia overcomes the disadvantages of the first generation and the second generation silicone hydrogel. A hydrophilic material that can be directly fused with the silicon material was found as the key composition of the polymerizable silicone hydrogel contact lens, and the formulation material achieved the revolutionary function of the third generation silicone hydrogel. Pharnorcia, breaking the international monopoly, is the world's leading and the only original supplier of third-generation silicone hydrogel contact lens formula materials in China.

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