DE2442514C3 - Dispersions of dyes, pigments and optical brighteners - Google Patents

Description

30th

For the production of storage and color-stable dispersions of dyes, pigments and optical A large number of nonionic, anionic and also cationic surfactants are used constantly increasing demands on the coloring and storage properties of the dye dispersions made further development of the dispersants used therein is necessary.

So show z. B. dispersions with 4b, which are often particularly good dispersing and highly liquefying Naphthalenesulfonic acid-formaldehyde condensates a stability which does not meet today's requirements, while other dispersants with good stability properties have a strong thickening effect on the May have dispersions.

The present application relates to dispersions of dyes, pigments and optical Brighteners, which are used as dispersants, condensation products of formaldehyde and sulfonated mono- or Contain dialkylnaphtha, the molar ratio of formaldehyde to sulfonated! Alkyl naphthalene 0.6: 1 to 0.9: 1 and the degree of sulfonation 0.5 to 2, is preferably 0.7 to 1 sulfonic acid group on each naphthalene ring.

These condensation products can be prepared from mono- and dialkylnaphthalenes, optionally with concomitant use of naphthalene and / or monohydric alcohols and / or naphthols by reaction with a sulfonating agent and subsequent condensation with formaldehyde or from corresponding sulfonic acid group-containing alkylnaphthalenes and formaldehyde by methods known per se getting produced.

The sulfonation of the alkylnaphthalenes takes place, for example, with 100% sulfuric acid, more concentrated * 5 Sulfuric acid or chlorosulfonic acid. Some of the alkylnaphthalenes can also be added Replace mixture of naphthalene and monohydric aliphatic alcohols, then under the conditions the sulfonation jealcdpn as well as the sulfonation an alkylation occurs

When using such mixtures of naphthalene and monohydric aliphatic alcohols the molar ratio of alkyl naphthalene to unsubstituted naphthalene is 1: 0.1 to 1: 1, preferably 1: 0.2 to 1: OA The molar ratio of naphthalene to Alcohol is between 1: 0 and 1: Z5.

Particularly suitable alkyl naphtha are products with 1 or 2 alkyl chains from Ci to C ₆ or corresponding mixtures or technical products. ! Accordingly, when working with mixtures with naphthalene, short-chain, monohydric alcohols up to C _{6 will be} used. The degree of sulfonation of the alkyl naphthalenes is chosen so that the molar ratio of alkyl naphthalenes: sulfonic acid group is 1: 0.5 to 1: 2, preferably 1: 0.7 to 1: 1 the condensation products also contain sulfonated naphthols. The molar ratio of alkylnaphthalenes to naphthol is between 1: 1 and 1: 0.2. The condensation of these products with the formaldehyde by known methods, for example 15 to 30 hours at a temperature of 50 ° C or about 5 to 10 hours at 105 ⁰ C.

The claimed dispersions are produced by known processes, for example the dyes, pigments or optical brighteners as filter press cake or in dried form with the dispersants or their aqueous solutions with as little water as possible to one The pumpable suspension is stirred on a high-speed stirrer (dissolver) if necessary for homogenization given over a corundum disk mill or similar colloid mills and then generally in a continuous agitator mill with quartzite beads 1 to 3 mm in diameter in possibly several passes ground to the desired fine distribution. After grinding, as well as when mixing further additives of bactericides, thickening agents, further dispersants and water to adjust the dough be made. To adjust the powder, a suitable dough is dried in a spray tower and then set to type conformity.

Inorganic and organic pigments, vat dyes and are suitable as dyes and pigments especially disperse dyes, as well as other insoluble or sparingly soluble dyes and optical ones Brightener.

The ratio of dispersant and dye can vary within wide limits and is im generally 03 to 10, preferably 0.5 to 2 parts by weight of dispersant to one part of dye powder.

Compared to the unsubstituted naphthalenesulfonic acid-formaldehyde condensation products the dispersants according to the invention produce dye dispersions with a very much better thermal stability in dyeing and storage.

The actual dispersing effect is also significantly improved and the milling time is reduced.

Compared to other commonly used dispersants, such as. B. those of the type in the Fiat Final Report 1013 mentioned condensation products of cresol, 2-naphthol-6-sulfonic acid, formaldehyde and Sulphite or opposite different lignin sulphonates !!

the dispersants used according to the invention have the advantage of a low inherent color. this means less soiling of the fiber, especially in blended fabrics with wool and makes use as a dispersant for optical brighteners S possible.

In addition, the dispersants used according to the invention have the ability to strongly increase aqueous press cakes of dyes or pigments liquefy, so that one often free-flowing dispersions with a significantly higher dye concentration can get.

By choosing the type and amount of alcohol used in the production, the Control the surface tension of the dispersants used according to the invention and thus above all the Influence network properties favorably.

20th

Examples

In the following examples A to K, the first Preparation of the substances later tested as dispersants are described. The parts are by parts by weight.

Dispersant A

To 200 parts of a crude mixture of 1- and 2-monomethylnaphthalene 220 parts is allowed at 90 ° C in 2 hours 100% sulfuric acid running, slowly heated with stirring to 140 ⁰ C and stirred until the water solubility of a sample. After cooling to ~ 70 ° C., 90 parts of water and 170 parts of formaldehyde (30%) are run in and this is kept at 80 ° C. for 20 hours

After dilution with 140 parts of water, precipitation is obtained by adding a suspension of 66 parts Calcium hydroxide in 100 parts of water neutralized the excess acid as sulfate and filtered. Finally the aqueous condensation product with sodium hydroxide solution. Spray drying produces an electrolyte-free mes powder.

Dispersant B

150 parts of 1,2-monomethylnaphthalene, 32.2 parts of naphthalene and 26.8 parts of n-butanol are used instead of the 200 parts of monomethylnaphthalene in Example A, the procedure otherwise as there is obtained particularly good wetting, low-electrolyte powder.

Dispersant C

To 250 parts of the crude mixture of monomethylnaphthalene used in the dispersants A and B is allowed at 90 ⁰ C in 2 hours 180 parts of sulfuric acid (96%) were run and heated to 14O ⁰ C. at a vacuum of 30 to 40 mm, the water of reaction is continuously distilled off until a sample is water-soluble. After cooling, the mixture is condensed at 80 ° C. by adding 290 parts of 19.0% formaldehyde for 20 hours. Subsequent neutralization with sodium hydroxide solution and spray drying give a powder with a low sodium sulfate content.

Dispersant D

200 parts of a crude mixture of dimethylnaphthalenes (main component about 40% 1,6-dimethylnaphthalene) are mixed with 220 parts of H2SO4 (100%) at 130 to

65 134 ° C in 4 Sauden sulfonated Subsequently, the water-soluble reaction product 7 (TC is cooled (30%) mixed with 90 parts of water and 170 parts of formaldehyde and condensed for 20 hours at 8O ⁰ C. After precipitation of the excess sulfuric acid with calcium hydroxide, is the aqueous sulfonic acid is neutralized with sodium hydroxide solution and spray-dried. A light brown powder with good dispersing properties is obtained

Dispersant E.

If you work with only 110 parts of formaldehyde, as with substance D, you also get a suitable dispersant

Dispersant F

If you work as with substance D, but omit the precipitation of the excess sulfuric acid with Ca (OH) ₂ , a light-colored powder containing sodium sulfate is obtained after neutralization and drying.

Dispersant G

A suitable product can also be obtained by using 100 parts of that for substance D. Dimethylnaphthalene and 100 parts of naphthalene are used and otherwise proceed as there

Dispersant H

According to the dispersing agent C are sulfonated 250 parts of the crude mixture of 1,6 dimethylnaphthalene with 180 parts of sulfuric acid (96%) while distilling off the water of reaction at 140 ⁰ C, with 320 parts of 19.0% formaldehyde for 20 hours at 8O ⁰ C condensed.

A light powder is obtained after neutralization. Dispersant J

100 parts of 2,3-dimethylnaphthalene and 100 parts of pure 1-monomethylnaphthalene are ^{sulfonated with 210 parts of sulfuric acid (100%) at 80 to 90 °} C. until a sample is soluble in water and, after the addition of 90 parts of water and 170 parts of formaldehyde (30%) condensed for 20 hours at 8O ⁰ C

After liming the excess sulfuric acid and neutralizing it with sodium hydroxide solution, one obtains after the Spray drying a light yellow powder.

Dispersant K

To a mixture of 100 parts of crude 1,6-dimethylnaphthalene and 100 parts of 0-naphthol, is allowed at 90 ⁰ C, 210 parts of sulfuric run (100%) and sulfonated at from 130 to 14O ⁰ C up to the water According substance D is reacted with formaldehyde condensed, limed, neutralized with sodium hydroxide solution and dried. The light powder has good dispersing properties.

For the comparison of the dispersing properties of the condensation products A to K, those in the German Offenlegungsschrift 21 32 403 described test methods and dyes used

In test methods 1 to 3, different soluble dyes are used in the presence of increasing amounts of the dispersant to be tested at 3 pH values

precipitated and their fine distribution was checked by the dispersant. The numbers given in the table represent the ratio of dye: dispersant in which the dye can be dispersed without residue, ie the smaller the given number, the greater the dispersibility - Agitator mill finely divided, the required meal time in hours is given in the table. The resulting dispersion is ^{stored at 50 °} C. and tested repeatedly

In the table, the tested time is given in days in which the dispersion has not yet settled had deteriorated. As a measure of the network properties the last column shows the surface tension of a 0.2% solution.

We have the results on our products A to K, the results on one of the Commercially available naphthalenesulfonic acid-formaldehyde condensation products, compared to the dispersant X.

This is a condensation product of naphtha-2-sulfonic acid with formaldehyde, which with Sodium carbonate was neutralized (BIOS Final Report 762, page 70 middle, edition of Hobard Publishing Company, Washington DC USA).

Dispersants Test procedure 2 3 4th Storage stability surfaces 1 pH PH Enjoy the meal in days tension at PH 9-13 H C = 2g / 1 2-5 (dyn / cm) Comparison: 0.125 0.5 5 Dispersant X 6th 0.065 2 2 <1 71 A. 1 0.125 <0.5 1 > 21 67 B. 1 0.125 1 1 > 21 58 C. 1 0.125 1.5 1 > 21 65 D. 1 005 03 2 > 14 67 E. 1.5 0.25 1 2 > 21 64 F. 2 0.25 1 1 > 21 68 G 2 0.125 1 1 > 21 62 H 1 0.125 0.5 2 > 21 60 J 1 0.125 1 3 > 21 58 K 1 > 21 63

In addition to this general comparison of the dispersing properties, the following examples are intended to provide a broad overview Make the spectrum of activity of the substances according to the invention clear:

example 1

40 Use about 20% more water and grind for about 3.5 hours to get a similarly fine one, but despite the lower level To obtain pigment content significantly more viscous dispersion.

After only one day of storage at 5O ⁰ C, the dispersion significantly deteriorated.

70 parts of a disperse dye, as described in DT-AS 22 38 378 in Example 71, are with 70 parts of dispersant D and 140 g of water ground in a 1-1 agitator mill for 6 hours.

The result is a dough that has good storage stability and is all coloristic requirements are sufficient If you work instead with 70 parts of a commercially available one Lignosulfonate, the heat stability of the dough is noticeably poorer. You get similarly good results with the dispersants A and H.

55

Example 2 Example 3

160 parts of a brightener as described in Example 1 of DT-PS 14 44 014 are 6.4 Parts of the dispersant H and 160 parts of water in an agitator mill for 2 hours until fine distribution ground and the dispersion diluted to a content of 20% brightener.

A stable, non-settling, low viscosity dispersion is obtained.

Example 4

80 g of a pigment such as that produced from the coupling of tetrazotized 3,3'-dichlorobenzidine to acetoacetic-m-xylidide are ground with 20 g of dispersant A and 90 g of water in a 1-1 agitator mill with quartzite beads for about 2 hours. A very flowing, very fine pigment dispersion is obtained, the fine distribution of which does not change ^{even after storage at 50 ° C. for several weeks.}

If the same amount of dispersant X is used instead of dispersant A, grinding must be carried out 100 parts of Dispersion Yellow 64 are mixed with 80 parts of the

Dispersant E with 60 parts of water in one

1-1 agitator mill finely divided in 2 hours, man receives a storage- and color-stable dispersion. Grinds one the same dye with dispersant X, so it takes about 4 hours to get the same

Fine distribution, but already after 1 day of storage

50 ° C clearly deteriorated

Similar good distributions are obtained with the dispersants A, D, and F.

7 8

Example 5

100 parts of Dispersion Violet 31 do not result in a stable dispersion with 80 parts after 6 hours of grinding, of dispersant B as in Example 4 in 2 hours. Good dispersions are obtained, for. B. also with the

finely divided, while dispersant X is also used to disperse 5 dispersants F and G.

Example 6

100 parts of Dispersion Blue 95 are mixed with 80 parts. Dispersant X is obtained after 6 hours

of the dispersant F in 4 hours for coloring and grinding, although good fine division, but not storage-stable dispersion is storage-stable as in the previous examples. ground.

Claims (1)

Patent claims: φ dispersions of i'arbstoffen, pigments and optical brighteners, characterized gekennxe I η et that they contain as dispersants Kondensatjonsprodukte of formaldehyde and sulfonated mono- or DialkylnaphthaUnen, wherein the molar ratio of formaldehyde to sulfonated! Alkylnaphthalene 0.6: 1 to 0.9: 1 and the degree of sulfonation is 0.5 to 2, preferably 0.7 to 1 sulfonic acid groups per naphthalene ring Z Dispersions according to Claim I, characterized in that the condensation products used as dispersants additionally contain 0.2 to 1 mol of naphthol per mol of alkylnaphthalene. 3. Dispersions according to claim 1, characterized in that the serving as dispersants Some condensation products are such alkylnaphthalenes Contained by alkylation of naphthalene with monohydric aliphatic alcohols have been obtained, the molar ratio of alkylnaphthalene to unsubstituted naphthalene 1: 0.1 to 1: 1, preferably 1: 0.2 to 1: 0.5 and that The molar ratio of naphthalene to alcohol is 1: 0 to 1: 2.5