Aqueous formulations, their manufacture and use

Abstract

Aqueous formulation containing (A) at least one pigment or at least one dyestuff, (B) at least one dispersant selected from (B1) copolymers of at least one ethylenically unsaturated C.sub.4-C.sub.10-dicarboxylic acid and at least one C.sub.4-C.sub.20-olefin and their respective alkali metal salts and (B2) aromatic sulfonic acids and their respective alkali metal salts.(C) at least one chelating agent selected from MGDA, GLDA, IDS and citric acid and their respective ammonium and alkali metal salts. (D) water, wherein the concentration of the pigment (A) or dyestuff (A) is in the range of from 5 to 500 ppm, referring to the total aqueous formulation, and wherein the weight ratio of dispersant (B) to the pigment (A) or dyestuff (A), respectively, is in the range of from 1:5 to 3:1.

Claims

1. An aqueous formulation, comprising: at least one pigment or at least one dyestuff, (A) at least one dispersant selected from the group consisting of (B1) a copolymer of at least one ethylenically unsaturated C.sub.4-C.sub.10-dicarboxylic acid and at least one C.sub.4-C.sub.20-olefin, and respective alkali metal salts, and (B2) an aromatic sulfonic acid and respective alkali metal salts (B) at least one chelating agent selected from the group consisting of MGDA, GLDA, IDS and citric acid and their respective ammonium and alkali metal salts, and (C) water, wherein: a concentration of the pigment (A) or dyestuff (A) is in the range of from 5 to 500 ppm, referring to the total aqueous formulation; and a weight ratio of the dispersant (B) to the pigment (A) or dyestuff (A), respectively, is in the range of from 1:5 to 3:1.

2. The aqueous formulation according to claim 1, wherein said formulation has a pH value in the range of from 8 to 14.

3. The aqueous formulation of claim 1, wherein said formulation is free from enzyme.

4. The aqueous formulation of claim 1, wherein said chelating agent (C) is selected from the group consisting of MGDA and GLDA and their respective alkali metal salts.

5. The aqueous formulation of claim 1, wherein said chelating agent (C) is a mixture of L- and D-enantiomers of methyl glycine diacetic acid (MGDA) or its respective mono-, di or trialkali metal or mono-, di- or triammonium salts, said mixture containing predominantly the respective L-isomer with an enantiomeric excess (ee) in the range of from 10 to 75%.

6. The aqueous formulation of claim 1, having a total solids content in the range of from 10 to 60% by weight.

7. The aqueous formulation of claim 1, wherein the dispersant (B) comprises an alkali metal salt of naphthalene sulfonic acids that may have been reacted with formaldehyde as the dispersant (B2).

8. The aqueous formulation of claim 1, wherein the dispersant (B) comprises the copolymer (B 1) in which the at least one C.sub.4-C.sub.20-olefin is diisobutene.

9. A transparent or translucent container containing the aqueous formulation of claim 1.

10. The container according to claim 9, wherein said container is made from polyvinyl alcohol.

11. The container of claim 9, wherein said container is a di-, tri- or multi-compartment container of which one compartment contains the aqueous formulation and the other compartment(s) do not.

12. The container of claim 9, wherein said container is a di- or tri- or multi-compartment pouch of which one compartment contains the aqueous formulation and the other compartment(s) do not.

13. A single unit dose for laundry cleaning or automatic dishwashing, the single unit dose comprising the container of claim 9.

14. A gel for automatic dishwashing, wherein the gel is formed from the aqueous formulation of claim 1.

15. A process for making an aqueous formulation according to claim 1, the process comprising mixing at least one chelating agent (C) with a mixture comprising at least one dispersant (B), at least one pigment (A) or at least one dyestuff (A), and water (D).

Description

I. MANUFACTURE OF INVENTIVE AQUEOUS FORMULATIONS

(1) General remark: The following substances were used: (A.1): CI Pigment Blue 15:1 (A.2): CI Acid Blue 9 (B2.1): polycondensate of -naphthalenesulfonic acid sodium salt, and formaldehyde, molar ratio about 1:1, molecular weight M.sub.w 5,700 g/mol, determined by GPC using a mixture of 60% by weight of 0.1 mol/l aqueous NaNO.sub.3 solution, 30% by weight of tetrahydrofurane (THF) and 10% by weight of acetonitrile as mobile phase and cross-linked hydroxyethylmethacrylate as stationary phase. As a standard, polymers of styrenesulfonic acid sodium salt and monomeric -naphthalenesulfonic acid sodium salt were used. (C.1): MGDA-Na.sub.3, (35% ee referring to the L-enantiomer), used as 40% by weight aqueous solution.
I.1 Manufacture of Inventive Aqueous Formulation (AF.1)

(2) Step (a.1): a mixture was provided by combining 40 g of pigment (A.1) and 55 g of dispersant (B2.1) and 5 g of Na.sub.2SO.sub.4 and 95 g of water (D) in a ball mill, followed by water removal by rotary evaporation, bath temperature 80 C., 8 hours. An amount of 0.2 g of the resultant mixture was diluted with 10 g of distilled water.

(3) Step (b.1): 0.5 g of the mixture obtained in step (a.1) were mixed with 100 g of 40% by weight solution of (C.1). Inventive aqueous formulation (AF.1) was obtained. Its pH value was 11, determined as 1% by weight aqueous solution.

(4) I.2 Manufacture of Comparative Aqueous Formulation C-(AF.2)

(5) Step (a.2): An aqueous solution containing (A.2) was prepared by adding 10 grams of distilled water (D) to a 0.2 gram of dyestuff (A.2).

(6) Step (b.2): 0.5 grams solution resulting from step (a.2) were added to 100 gram of 40% by weight solution of (C.1).

(7) For comparison purposes, the mixtures according to step (a.1) and (a.2) were each diluted with 80 g of water instead of solution of (C.1). Comparative aqueous formulations C-(AF.3) and C-(AF.4) were obtained.

(8) II. Tests Of Color Stability

(9) The color intensity was measured directly after manufacture, 1 day after manufacture and 7 days after manufacture. The measurements were performed at visible light at 23 C. and UV light, wavelength 366 nm, at 28 C. The evaluation was performed according to CIELAB.

(10) TABLE-US-00001 TABLE 1 color stability measured with visible light 1 min after manufacture 1 d after manufacture 7 d after manufacture L* a* b* L* a* b* L* a* b* (AF.1) 52.6 54.8 31.3 52.3 53.2 31.5 51.9 53.8 32.0 C-(AF.2) 59.9 40.9 44.2 48.5 47.6 61.4 86.3 13.6 12.3 C-(AF.3) 52.9 46.2 39.1 52.7 44.2 40.8 52.7 44.3 40.8 C-(AF.4) 56.9 19.6 61.3 56.5 17.9 62.2 56.5 17.7 62.4 L*: Lightness value, may be in the range of from 0 to 100. 0: ideal black. 100: ideal white

(11) TABLE-US-00002 TABLE 2 color stability tests with UV light, wavelength 366 nm 1 min after manufacture 1 d after manufacture 7 d after manufacture L* a* b* L* a* b* L* a* b* (AF.1) 52.6 54.8 31.3 52.3 53.2 31.5 54.5 49.9 32.0 C-(AF.2) 59.9 40.9 44.2 93.1 1.0 7.1 95.9 0.9 3.6 C-(AF.3) 52.9 46.2 39.1 52.5 45.4 39.4 51.5 46.8 37.4 C-(AF.4) 56.9 19.6 61.3 56.3 17.9 62.2 56.5 17.8 62.4

(12) The colour of the inventive aqueous formulation remained brilliant while the comparative aqueous formulations either showed drastic fading of their colour or even turned pale purple.