SA-18, SA-32 (kolfocon A, B)
Silicone-acrylate (SA) polymers were the first major improvement over the original polymethyl methacrylate (PMMA) materials. Silicone allows oxygen to pass through the material and when combined with the excellent optical qualities of PMMA, it made for a material that could be fit on the cornea with less edema and increased comfort. Several companies introduced SA materials in ranges of limited permeabilities in the 1980s. The formulations of these materials differ only in minor variations in the concentrations of monomers, wetting agents and crosslinkers. Lagado’s SA materials offer the same quality and performance to the higher priced, name-brand counterparts with one important distinction - Lagado SA blanks are also available with a UV Absorber. Lagado’s SA blanks are manufactured in permeabilities (Dk) of: 18 and 32. Blanks are precision machined to 12.70mm x 4.40mm.
|Oxygen Permeability (Dk)||18, 32|
|Refractive Index||1.489, 1.467|
|Hardness (Shore)||D/87, D/86|
|Specific Gravity||1.126, 1.101|
|Stock Colors||medium and dark shades of blue, green, gray and brown; violet and clear; with or without a UV absorber|