The present invention is concerned with new 3-sub
stituted derivatives of 7-aminocoumarin which, because
of their intensive blue to blue-green ?uorscence, are suit
able as optical brightening agents for more or less
colourless organic material, in particular for organic
textile ?bres of the most varying origin as well as for
polymeric synthetic materials. They are also suitable
as intermediate- products for the production of optical
brightening agents. The invention also concerns proc
esses for. the production of the new B-substituted deriva
tives' of 7-aminocoumarin. It is further concerned with
' processes for the brightening of organic material with
the new coumarin derivatives as well as, as industrial
product, the material brightened with the aid of these
compounds.