摘要 |
<p>Light-collecting system, characterized in that it contains a dyestuff of the formula <IMAGE> (I) in which Hal designates identical or different halogen atoms from the series comprising fluorine, chlorine and bromine, R1 and R2 designate hydrogen or optionally substituted C1-C18-alkyl and n designates 4-5, and new dyestuffs of the formula I which in a 0.5-2 mM solution in path lengths of 10 cm display an increase in transmission from 0 to >95% with a change in the wavelength of 25-120 nm.</p> |