Small science about the water content of contact lenses

Contact lens water content is an important parameter related to wear and use, today, we will do a small science about the water content of contact lenses, hoping to help you more comprehensively understand the water content of contact lenses.

Water content refers to the percentage of water in contact lenses after full absorption and saturation, we all know that the contact lens material itself is very hydrophilic, so the proportion of water in the total weight of the lens is very large. At present, there are roughly three categories of water content, less than 40% is considered as low water content, between 40%-60% is the conventional value, and more than 60% we can call it high water content.

As a basic property of contact lenses, water content has an impact on all aspects of the lens. After the water content increases, the oxygen permeability and comfort of the lens will be improved, which is a more positive positive impact, and the hydrated lens is easier to be accepted by the eye, so the need to adapt to the time is correspondingly shorter, and it is not easy to produce foreign body sensation and rejection. Of course, the relative water content will also bring some negative effects, such as the lens is too soft will be easy to deformation and even damage, the process is a relatively big test, while the sediment is more easy to produce and accumulate, to clean up also brought some difficulties. Due to the strong correlation between water content and material, the level of water content in the process may be limited.

Due to the characteristics of water content, many people are easy to misunderstand this parameter. Water content refers to the lens contains water, but it does not produce water itself, so the process of wearing is still facing the problem of water evaporation, when the lens is insufficient water, it is necessary to absorb tears from the eyes as water supplement. If you can not soak in the care solution, then contact lenses will soon shrink, dry, brittle, which shows that the water evaporation rate of contact lenses is still very fast. The high water content of contact lenses not only the water evaporation speed, the amount of absorbed tears is also larger, which may be very different from the high water content we understand, rash choice may make the eyes more uncomfortable.

So, high water content is not an option? For contact lenses, water content is not the same as water locking. In order to maintain moisture and slow down water evaporation, many big brands have made a lot of technical updates on the moisturizing properties of lenses, so we can not look at the level of water content alone when buying!