PPG Industries, Inc. v. United States, Vitro Flex, S.A. and Cristales Inastillables de Mexico, S.A. 12 December 1991 - World Trade and Arbitration Materials View PPG Industries, Inc. v. United States, Vitro Flex, S.A. and Cristales Inastillables de Mexico, S.A. 12 December 1991 by - World Trade and Arbitration Materials PPG Industries, Inc. v. United States, Vitro Flex, S.A. and Cristales Inastillables de Mexico, S.A. 12 December 1991 4 1 World Trade and Arbitration Materials