Alkanolammonium-containing triazinyl flavonate whiteners

Abstract

Process for whitening paper in the size press, characterized in that the size press liquor contains a whitener of the formula I in which X, independently of one another, denote a radical of the formula and R1 represents C1-C6-alkyl and R2 represents H, or R1 represents H and R2 represents C1-C6-alkyl, and, independently thereof, R3 represents H, methyl, ethyl, CH2CH2OH or CH2CH2OCH3, R1′ represents C1-C6-alkyl and R2′ represents H, or R1′ represents H and R2′ represents C1-C6-alkyl, and, independently thereof, R3′ represents H, methyl, ethyl, CH2CH2OH or CH2CH2OCH3 and R4 represents C1-C4-alkyl and M denotes H, one equivalent of an inorganic cation, in particular Li, Na, K, Ca, Mg or ammonium, or a substituted ammonium of the formula II in which R5 to R7, independently of one another, denote hydrogen, a C1-C4-alkyl radical or an optionally further substituted C2-C4-hydroxyalkyl radical, and R8 denotes an optionally further substituted C2-C4-hydroxyalkyl radical, at least 10 mol % of all cations M corresponding to the formula II.

Dependencies are inferred from the claim text.