Patent ID: 7242542

Claim:
A filter of an electronic display device, said filter comprising a squarylium compound represented by formula (II): wherein R 15 and R 17 independently represent a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, a nitro group, a cyano group, a hydroxyl group, a substituted or unsubstituted amino group, or a substituted or unsubstituted heterocyclic group; R 16 and R 18 independently represent an alkoxyalkoxyl-substituted alkyl group; R 19 and R 20 independently represent a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, a nitro group, a cyano group, a hydroxyl group, a substituted or unsubstituted amino group, or a substituted or unsubstituted heterocyclic group; m represents an integer of 0 to 4, wherein, when m is 2 to 4, R 19 's may be the same or different, respectively; and n represents an integer of 0 to 4, wherein, when n is 2 to 4, R 20 's may be the same or different, respectively.