5FORBES H R,SHEETS A H. Polymer Orientation: US Patent 5 565 163[P]. 1996.
6SAWADA M, FUKUKITA H, FUKUOKA T. Anti-fogging Thermoplastic Resin Sheet and Formed Article:US Patent 6 838 168[P]. 2005.
7HIRAISHI H, TAKAHASHI M. Surface Reforming Method for Plastic Molded Produet:US Patent 6 517 752[P]. 2003.
8OYA K,SAWADA S,TOYODA H, et al. Multilayered Biaxially- oriented Styrene Based Resin Sheet and Method for Production Thereof: US Patent 6 572 806[P]. 2003.
10FRANCESSO A D, DUCKETT R A. Effects of Orientation on Mechanical Properties of Uniaxially Oriented Polystyrene Films [J]. Polymer, 2004,45 : 8005 - 8011.