Stable colorant compositions

• US 6,080,209 A
• Filed: 09/25/1998
• Issued: 06/27/2000
• Est. Priority Date: 03/26/1996
• Status: Expired due to Fees

• Current Assignee: BASF AG (BASF SE)
• Original Assignee: BASF AG (BASF SE)
• Inventors: Paulus, Rudolf, Herrmann, Manfred, Dix, Johannes Peter, Wiesenfeldt, Matthias
• Primary Examiner(s): LIOTT, CAROLINE L
• Application Number:
  US09/147,049
• Time in Patent Office: 641 Days
• Field of Search: 8/436, 8/437, 8/557, 8/558, 8/618, 8/637.1, 8/681, 8/682, 8/683, 8/685, 8/687, 8/676
• US Class Current: 8/437
• CPC Class Codes: C09B 67/0033 Blends of pigments; Mixtured crystals; Solid solutions
• CPC Class Codes: C09B 67/0041 mixtures containing one azo dye
• CPC Class Codes: D06P 1/44 using insoluble pigments or auxiliary substances, e.g. binders
• CPC Class Codes: D06P 1/5257 (Meth)acrylic acid
• CPC Class Codes: D06P 3/32 leather skins
• CPC Class Codes: D06P 3/3226 dis-polyazo

Abstract

Stable aqueous dye compositions containing at least one anionic colorant and at least one pigment and a polyanionic thickening agent. The dye compositions may be used to dye leather.

Claims

1. A colorant composition, comprising:

8-40% by weight of at least one anionic dye selected from the group consisting of azo dyes, metal phthalocyanine dyes, and anthraquinone dyes substituted by at least one sulfonic acid group,

2-30% by weight of at least one pigment,

1-20% by weight of a polymeric polyanionic thickener, and

50-92% by weight of water or a predominantly aqueous diluent.

2. Colorant compositions as claimed in claim 1, comprising an acid dye of the general formula I ##STR10## where R¹ and R² are each hydroxyl, amino or hydrogen, one of the radicals being hydroxyl,

R³ and R⁴ are each hydrogen or SO₃ H, at least one of the radicals being SO₃ H,

R⁵ is a substituted or unsubstituted phenyl or naphthyl radical,

R⁶ is a substituted phenyl or naphthyl radical, at least one substituent being an amino or hydroxyl group, and

A is ##STR11## where the aromatic rings are substituted or unsubstituted.

3. Colorant compositions as claimed in claim 1, comprising an acid dye of the formula II ##STR12## where B is a substituted phenylene or naphthylene radical, one substituent being a hydroxyl group ortho to the diazo group, and

R⁷ is hydrogen or ##STR13## which is substituted or unsubstituted in the aromatic ring system, or a metal complex thereof.

4. Colorant compositions as claimed in claim 1, wherein the pigments and dyes are black.

5. Colorant compositions as claimed in claim 1 comprising carbon black pigments.

6. Colorant compositions as claimed in claim 1 comprising one or more iron oxide pigments.

7. Colorant compositions as claimed in claim 1, wherein the polyanionic thickener is an acrylic acid polymer or copolymer.

8. A process for dyeing leather by the exhaust method, which comprises contracting the leather with an aqueous liquor comprising a colorant composition as claimed in claim 1.

9. A colorant composition, comprising:

8-18% by weight of at least one anionic dye selected from the group consisting of azo dyes, metal phthalocyanine dyes, and anthraquinone dyes substituted by at least one sulfonic acid group,

5-17% by weight of at least one pigment,

3-15% by weight of a polymeric polyanionic thickener, and

50-84% by weight of water or a predominantly aqueous diluent.