Aromatic methylidene compounds, aromatic aldehyde compounds and methylstyryl compounds used to prepare the methylidene compounds, and methods for preparing these compounds

Granted: Oct 7, 2003 Filed: Jan 24, 2002

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.