ALKANOL-AMMONIA CONTAINING TRIAZINYLFLAVONAT BRIGHTENER

Method for whitening paper in the size press comprises a size press fleet containing an alkanolammonium containing triazinyl flavone compound (I) as the optical whitener. Method for whitening paper in the size press comprises a size press fleet containing an alkanolammonium containing triazinyl flavone compound of formula (I) as the optical whitener. X : alkyl compounds of formula (a) or (b); either R 1>, R-1a : 1-6C alkyl; and R 2>, R-2a : H; or R 3>, R-3a : H, CH 3, CH 2CH 3, CH 2CH 2OH or CH 2CH 2OCH 3; R 4>H or 1-4C alkyl; M : an equivalent inorganic cation (preferably Li, Na, K, Ca, Mg or ammonium) or a substituted ammonium of formula (II) (where at least 10 mol.% of all cation corresponds to formula (II)); R 5>-R 7>H, 1-4C alkyl or optionally substituted 2-4C hydroxyalkyl; and R 8>optionally further substituted 2-4C hydroxy alkyl. Independent claims are also included for: (1) an optical whitener preparation comprising more than 50 (preferably more than 95) wt.% of (I); and (2) a size press fleet comprising (I) or an optical whitener preparation and at least a surface sizing agent (preferably starch). [Image] [Image] [Image].