Back to results
US 9,487,503 B2Granted
Stilbene optical brighteners
Assignee3V Sigma S.p.A.
InventorsFerruccio Berte', Patrick Alborghetti
Life of this patent
Estimating the term…
Abstract
The present invention discloses compounds of 4,4′-diaminostilbene-2,2′-disulphonic acid which are useful as optical brighteners to bleach fibers, cellulose and in particular paper and cardboard.
Claims10
Compounds of formula (I)
- wherein
- n is 0, 1 or 2;
- Y is H, C1-C4 alkyl, LOOM, —CO—CH3, —SO2-NH2, —CN;
- m is 0, 1 or 2;
- R, R1, R2, R3, which can be the same or different, are H, methyl, ethyl;
- the M groups are independently H, Li, Na, K, Ca, Mg, ammonium, protonated ions deriving from alkylamines, alkanolamines or alkylalkanolamines;
- A is selected from the group consisting of H, C1-C8 alkyl, C3-C8 cycloalkyl, C1-C8 hydroxyalkyl, alkoxyalkyl, phenyl, alkylphenyl, the side chain of an amino carboxylic or sulphonic acid in which the carboxylic or sulphonic groups are salified with the M group as defined above, or the SO3M group, M being as defined above;
- the hydrated forms thereof, either solid or in powder.
5 more elements
A process for the production of the compounds of formula (I) which comprises the reaction of cyanuryl chloride in three steps in the presence of water or solvents and of proton acceptors with 4,4′-diaminostylbene-2,2′-disulphonic acid, with two mols of an amine and with two mols of a different amine of formula (III).
Dependencies are inferred from the claim text.