Black-white liquid crystal display having an insulation layer for blocking the diffusion of sodium ions from the glass of the cell plate to the polyphenylene of the orientation layer

Granted: Dec 10, 1991 Filed: Dec 19, 1989

This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.