As we all know, contact lenses themselves do not produce water, so what is the water content of contact lenses?
For contact lenses, water content is the percentage of the water contained when the material is saturated. Generally 38% -42% is low water content, more than 59%, is high water content. When the lens is low, it absorbs tears to replenish the missing water. Low water content although high durability, but the oxygen permeability is slightly low, and high water content oxygen permeability is strong, but easy to deformation and damage.
So why do we mention the water content parameter frequently? In fact, when you wear your contact lenses, the oxygen needed for corneal breathing is first dissolved in water before passing through the contact lenses. The water in the contact lenses forms the one responsible for the oxygen delivery channel, so the high water content also means the increased oxygen permeability coefficient, so it occupies a very important position.
Although the water content is related to the oxygen permeability, it is not that the higher the water content, the better, but according to the individual tear secretion function. Too high water content also accelerates the speed of water evaporation, but it is easy to cause dry eyes, so people with less tears secretion had better choose contact lenses with lower water content. At the same time, wearing the same environment can have some effects, such as wearing low-water contact lenses in a dry climate or in air-conditioned rooms.
In a word, the water content has a great relationship with the overall wearing comfort and the oxygen permeability of the lens. It can be paid appropriate attention to, but we must not excessively pursue high water content, and just need to choose the suitable water content according to the actual needs.