US Patent 7544747 - Photovoltaic fullerene

http://www.freepatentsonline.com/7544747.html

This patent from Konarka Technologies teaches a composite fullerene materials that may be useful in producing flexible solar cells. Claim 1 reads:

1. A fullerene derivative, comprising a pendant cyclic ether and a fullerene comprising a number Cj carbon atoms, wherein j ranges from 50 to 250 and the pendant cyclic ether and the fullerene are spaced apart by an ester group or a ketone group.