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US 4,237,050 AGranted
Process for the preparation of water-soluble phthalocyanine dyestuffs
AssigneeHoechst Aktiengesellschaft
InventorHartmut Springer
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AssigneeHoechst Aktiengesellschaft
InventorHartmut Springer
Estimating the term…
A process for the preparation of water-soluble phthalocyanine dyestuffs containing a fiber-reactive group of the vinylsulfone series, by reacting phthalocyanine sulfochlorides, optionally containing sulfo groups, with a primary or secondary amine which contains a fiber-reactive group of the vinylsulfone series, and optionally with a further primary or secondary amine in common manner, wherein according to the invention a pyridine-sulfonic acid or a pyridine-carboxylic acid is used as catalyst instead of the pyridine, as used previously. The use of pyridine-sulfonic acids or pyridine-carboxylic acids--which results in the same good reaction rate and yield as the use of pyridine in the preparation of phthalocyanine dyestuffs--avoids the considerable drawbacks occurring in the preparation on an industrial scale, which drawbacks are caused by the toxic properties and the unpleasant smell of the pyridine.
In a process for the preparation of a water-soluble phthalocyanine dyestuff by reacting a phthalocyanine-sulfonic acid chloride or a phthalocyanine-sulfonic acid chloride containing sulfo groups, with a primary or secondary amine which contains one or several .beta.-substituted ethylsulfonyl groups or one or several vinylsulfonyl groups, or with said amine and also a second primary or secondary amine of the aliphatic, heterocyclic or aromatic series, the improvement which comprises so reacting in the presence of a pyridine-sulfonic acid or a pyridine-carboxylic acid compound.
Dependencies are inferred from the claim text.