An Experimental Study on the Reduction of a Birefringence Distribution in LGP by Injection-Press Molding

형체압축성형을 이용한 도광판의 복굴절 저감효과에 관한 실험적 연구

  • 민인기 (한국생산기술연구원 정밀금형팀) ;
  • 김종선 (한국생산기술연구원 정밀금형팀) ;
  • 고영배 (한국생산기술연구원 정밀금형팀) ;
  • 박형필 (한국생산기술연구원 정밀금형팀) ;
  • 윤경환 (단국대학교 기계공학과) ;
  • 황철진 (한국생산기술연구원)
  • Published : 2005.09.01


The residual birefringence in molded plastic parts can be divided into two kinds of residual birefringence, i.e., the flow induced residual birefringence produced in flowing stages and the thermally induced residual birefringence produced in cooling stage. In this paper, the effect of new injection-press molding process with normal injection mold, i.e. I) injection-compression mode, ii) injection-press mode, on the distribution of birefringence was studied. It was found that the values of the birefringence was reduced at i) low clamping force and ii) longer mold opening length by injection-press molding.