Patent ID: 6280808
Filing Date: 2001-08-28
Classification: B29C,B29L,Y10S,Y10T

Abstract:
A 3-dimensional optical storage medium comprising a high quality plastic sheet having dispersed thereon one or more pigments, dyes or mixtures thereof, wherein the pigments, dyes or mixtures thereof undergo a change in optical properties locally upon exposure to light; wherein the optical storage medium is produced by the steps of:a) providing molten plastic resin;b) directing the molten plastic resin to an overflow die having an inlet and an outlet;c) shaping the molten plastic resin into a molten web using said overflow die;d) combining the pigment, dye or mixture thereof with the molten plastic resin prior to shaping the molten resin into a web using said overflow die;e) guiding said molten web away from said overflow die; andf) cooling said molten web to form a solid;wherein the high quality plastic sheet has a birefringence of less than or equal to 0.0002.