摘要 |
Polycarbonate materials are dyed by immersion into a mixture of dye or pigment dissolved in a solvent blend. The blend is made up of an impregnating solvent, which attacks the polycarbonate and allows impregnation of the dye or pigment, and a moderating solvent which reduces the aggressiveness of the impregnating solvent. A graded tint is provided by slowly withdrawing the immersed polycarbonate material from the mixture. Polycarbonate materials having a graded tint, especially sheets in the form of lenses and goggles, are also provided.
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