Disazo dyestuffs
AssigneeBayer Aktiengesellschaft
InventorsKlaus Kunde, Wolfgang Zarges
Life of this patent
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Abstract
The new disazo dyestuffs of the formula (I) ##STR1## wherein the substituents and the indices have the meanings given in the description, wherein more than 25 equivalent % of all the M cations in the molecule are alcohol ammonium radicals of the formula .sup..sym. NR.sub.1 R.sub.2 R.sub.3 R.sub.4 wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 independently of one another represent hydrogen, C.sub.1 -C.sub.4 -alkyl and C.sub.2 -C.sub.4 -hydroxyalkyl, with the proviso that at least one of the radicals R.sub.1 -R.sub.4 denotes C.sub.2 -C.sub.4 -hydroxyalkyl, are excellently suitable for dyeing cellulose-containing materials, and in particular paper, and are distinguished by high degrees of fastness.
Claims17
A dyestuff having the formula ##STR16## wherein A represents a radical of the formula ##STR17## R represents hydrogen, and M represents one or more cations, wherein more than 25 equivalent % of said cations M are ammonium radicals of the formula .sup.+ NR.sub.1 R.sub.2 R.sub.3 R.sub.4 wherein R.sub.1, R.sub.2, R.sub.3, and R.sub.4 independently of one another represent hydrogen, C.sub.1 --C.sub.4 alkyl, or C.sub.2 --C.sub.4 hydroxyalkyl.
A dyestuff of formula (I) ##STR18## wherein A represents a radical of the formula ##STR19## or ##STR20## wherein Ac represents an acetyl or propionyl radical or a benzoyl radical optionally substituted by CH.sub.3, CH.sub.3 O, or COOM,
- m, n, p, and q represent 0 or 1, with the proviso that the sum m+p=1,
- R represents a benzoyl radical optionally substituted by CH.sub.3, CH.sub.3 O, or COOM, and
- M represents one or more cations, wherein more than 25 equivalent % of said cations M are ammonium radicals of the formula .sup.+ NR.sub.1 R.sub.2 R.sub.3 R.sub.4 wherein R.sub.1, R.sub.2, R.sub.3, and R.sub.4 independently of one another represent hydrogen, C.sub.1 -C.sub.4 alkyl, or C.sub.2 -C.sub.4 hydroxyalkyl.
A process comprising membrane filtering an aqueous solution or suspension of a dyestuff of formula (I) wherein
- A represents a radical of the formula ##STR28## wherein Ac represents an acetyl or propionyl radical or a benzoyl radical optionally substituted by CH.sub.3, CH.sub.3 O, or COOM,
- m, n, p, and q represent 0 or 1, with the proviso that the sum m+p=1,
- R represents hydrogen or a benzoyl radical optionally substituted by CH.sub.3, CH.sub.3 O, or COOM, with the proviso that R is not hydrogen when m is 1, n is 0, and q is 0, and
- M represents Na.sup.+, Li.sup.+, and/or K.sup.+, in the presence of an ammonium salt of the formula .sup.+ NR.sub.1 R.sub.2 R.sub.3 R, An wherein R.sub.1, R.sub.2,
- R.sub.3, and R.sub.4 independently represent hydrogen, C.sub.1 -C.sub.4 alkyl, or C.sub.2 -C.sub.4 hydroxyalkyl and
- An.sup.- represents an inorganic anion.
Dependencies are inferred from the claim text.