A variety of dyes are commercially available today, there is an ongoing need for new chromophoric systems and low-band-gap materials. For example, near-infrared (NIR) emission has received increased attention for applications in bioassays and medicine while NIR absorption is demanded for laser-welding of plastics or efficient blocking of heat rays. Most of the commercially available NIR materials are not suitable for such purposes owing to their insufficient stability. We have developed a novel NIR-absorbing polyaromatic dye. By extending the system of perylenebis(dicarboximide)s along the molecular long axis, we have obtained the higher homologue pentarylenebis(dicarboximide). We have tried to introduce imide functional group to pentarylene in order to increase chemical and thermal stability.
