Hi,
I'm new, I do not know if you have discussed this, but DataFrame.to_excel seems to not work with openpyxl-2.2+. "Unexpected argument 'font' for copy()." Editing line 778 in pandas.io.excel seems to work for some people, though even that does not work in my case. Also while reading from .xlsx, datetime formats are timestamped but while writing back they seem to be behaving weirdly.
Thank You
Aditya