Contact lens material to decrypt the —— hydrogel

Soft contact lenses are made of organic polymer materials, its development can be traced back to 1960, by the Czech scientists first synthesized PHEMA methacrylate, thus produced the first pair of soft contact lenses. This is an important node in the development of soft contact lenses and the basis for the development of silicon hydrogel materials.

Hydrogel has long been a popular material for soft contact lenses, which is widely used in the process of making contact lenses and occupies an important position in the market. In the long history of development, the technology is gradually becoming mature. In fact, in addition, due to the high water content, high water retention, high biocompatibility characteristics, it is also used in medical dressings, beauty materials, soil conservation and other fields.

The advantages of hydrogel contact lenses lie in their high water content and soft texture, compared with a great breakthrough in hard contact lenses. Its toughness and elasticity is excellent, strong plasticity, so even as a foreign body, can also let the eye to adapt quickly, and the physiological compatibility of the cornea is very high, can be effortless.

But on the other hand, the disadvantages of hydrogel contact lenses are also more obvious. It is easy to dehydrate, and oxygen will lose an important channel after water loss, resulting in a significant reduction in oxygen permeability, and corneal hypoxia may appear after wearing for a long time. In addition, the higher the water content, the faster the evaporation rate, and the more water will be absorbed from the tears to supplement its lack of water, which may disrupt the normal tear secretion, and the long probability will develop into dry eye disease.

Because the use period of hydrogel contact lenses is long, it is easy to accumulate precipitation. Once the sediment remains on the lens, the material and oxygen transmission performance will be affected, so in order to ensure the service life and wearing effect, please do a good job of cleaning in time. At the same time, must also strictly control the wearing time, not continuous wear.