The dithiolene dyes are valuable for their thermal stability.  They absorb in the near infrared over a wide range of wavelengths depending upon the organic groups on the dithiolene ring.  Their properties of solubility and absorptivity are also tied to the organic groups on the ring carbon atoms.

Most dithiolenes are high melting solids, which have very low solubility in common organic solvents.  They show excellent compatibility in polycarbonate and other resins.  There is no evidence of bloom and they appear to be quite stable to long term heat exposure.

Dithiolenes degrade slowly in sunlight but this is similar to any organic soluble dye. Their light stability is greater than the amminium dyes of the 1000 and 2000 series.

Aliphatic derivatives, where "R" is methyl or propyl, have their peak absorption below 800nm. Aromatic substitution, where "R" is phenyl or substituted phenyl, produce dyes with absorption between 850 and 1000nm. 
 
When an electron-rich donating group such as the dialkylamino group is substituted on the aromatic ring, absorption peaks at 1050nm or higher.

Epolight™	lambda max, nm	substitution
3079	771	aliphatic
3036	773	aliphatic
3211	785	aliphatic
3030	791	aliphatic
3442	817	aliphatic & aromatic
3063	858	aromatic
3443	868	aromatic
3157	886	aromatic
3159	890	aromatic
3116	892	aromatic
3182	907	aromatic
3138	924	aromatic
3185	931	aromatic
3169	934	aromatic
3130	950	aromatic
3072	1054	aromatic