06.02.14
US Patent No. 8,702,816 B2; Michael D. Conte of Fort Worth, TX has patented a method to create a reversibly dyed hydrogel or silicon hydrogel substrate/soft contact lens. A hydrogel or silicon hydrogel substrate (a soft contact lens) is immersed in a saline solution, wherein the substrate has a non-dyed appearance; a dye is added to the solution, producing a combination solution; the hydrogel or silicon hydrogel substrate/soft contact lens remains in the combination solution for an amount of time at a temperature from about 60°F to about 82°F, wherein the dye does not print color into any part of the soft contact lens matrix; and removing the hydrogel or silicon hydrogel substrate from the combination solution to produce a reversibly dyed hydrogel or silicon hydrogel substrate. The reversibly dyed hydrogel or silicon hydrogel substrate returns to its non-dyed appearance over time and the dye is removable by soaking in a saline solution.