Novel stilbene compounds of the formula ##STR1## in which R.sub.1 and R.sub.2 independently of one another are hydrogen or chlorine and A is a mono-nuclear or poly-nuclear aromatic heterocyclic structure which contains oxygen atoms or oxygen and nitrogen atoms and is unsubstituted or substituted by non-chromophoric substituents, as well as their use in a process for optically brightening organic material are disclosed.
本发明涉及一种新型的
蒽烯衍
生物,其
化学式为##STR1##其中R.sub.1和R.sub.2是独立的氢或
氯,A是一种含有氧原子或氧和氮原子的单核或多核芳香杂环结构,该结构未被取代或被非色团取代,以及它们在有机材料光学增白过程中的应用。