Copper phthalocyanines having trimethylammoniummethyl groups as paper dyes
AssigneeSandoz Ltd.
InventorHelmut Moser
Life of this patent
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Abstract
Dyes of the formula CuPc--CH.sub.2 --N.sup..sym. (CH.sub.3).sub.3 Cl.sup..crclbar.).sub.n, wherein CuPc is copper phthalocyanine, and n is 2 or 3, and mixtures thereof, are useful as paper dyes. The dyes may be added to paper stock prior to sheet formation or applied to paper in sheet form to produce turquoise colored paper. The dyed or printed paper is bleachable but has good fastness to light, wet treatments, alcohol and soap. The dyes are very soluble in water and exhaust well on, i.e., exhibit good substantivity to, paper.
Claims7
A process for producing turquoise paper comprising (a) incorporating into paper stock an effective amount of a dye of the formula
- CuPc--CH.sub.2 --N(CH.sub.3).sub.3 Cl.sup..crclbar.).sub.n,
- or a mixture thereof, wherein
- CuPc is a copper phthalocyanine radical having not more than 0.5 mol of sulfo group per molecule, and
- n is 2 or 3,
- said effective amount being an amount sufficient to impart the desired turquoise color to the paper to be formed, and (b) forming turquoise paper from said paper stock.
Dependencies are inferred from the claim text.