CS242280B1 - Dispersing agent - Google Patents

Description

The present invention relates to a dispersion composition based on polycondensate of naphthalenesulfonic acid with formaldehyde for dyeing and printing textile materials, which consists of 92 to 97 parts of sodium polycondensate of 2-naphthalenesulfonic acid with formaldehyde of the general formula:

where η = 1 to 8, up to 7 parts sodium sulfate and water.

The present invention relates to a sodium-sodium dispersant of 2-naphthalenesulfonic acid polycondehzate with formaldehyde. A wide range of dispersants for dyeing and printing textile materials is known worldwide. Some processes are based on the sulfonation product = naphthalene, where 1-naphthalenesulfonic acid predominates, and during the condensation, naphthalene is added to the reaction mixture at a ratio of 70: 30 based on naphthalenesulfonic acids.

The dispersant thus prepared is very light but poorly soluble in water, and its solutions must be maintained at higher temperatures. At ambient temperature, the condensate crystallizes from aqueous solutions. Dispersants for the insoluble colorants of higher naphthalene sulfo acids have a lower dispersing effect. j

The prior art processes successfully allow the condensation of naphthalenesulfonic acids with formaldehyde to a molar ratio of 1: 0.65. Above this ratio in favor of formaldehyde, the crosslinking of the product leads to disadvantageous viscosity growth and the reaction must be terminated before reaching higher condensation stages, which results in low stability of the dispersant in a strongly alkaline environment, e.g. dyeing of the viscosity in the fiber.

The above-mentioned disadvantages are eliminated by the dispersant according to the invention, which consists of 92 to 97 parts by weight of sodium polycondensate of 2-naphthalenesulfonic acid with formaldehyde of the general formula

where η = 1 to 8, up to 7 parts sodium sulfate and water.

The dispersant according to the invention is characterized by a high dispersing efficiency and a high dispersion stability.

The dispersing efficacy was tested by grinding Ostacet dyes on a bead mill with a minimum amount of Ligraf ASK (lignin sulphonate to drop test level P3 to 4 and after adding the appropriate amount of ground sample with a dispersant (2-naphthalenesulfonic acid-formaldehyde condensate in 1: 0.86 molar ratio) Sodium dinaphthyl methanesulfonate, where both dispersants had the same sodium sulfate content of 5%] per strength of the standard type, we obtained a dispersion "solution" corresponding to a quantum level of 1 g of merchandise.

We tested the 100 ml water-filled samples with a cold drop test (KT _S ), a drop test after 3 minutes of boiling (KTJ and hot filtration test (FT _V ), and then with dispersion stability according to current standards after grinding on a corundum disperser mill.

EXAMPLE 1 g Ostacet Yellow P-2G was ground with 0.625 g of Ligraf ASK per drop test P 3-4. After filtering and washing the Balotin, 355 ml of dispersion were obtained. To 28.4 ml of this dispersion containing 0.45 g dry matter was added 0.55 g of the chosen dispersant (dispersant according to the invention and sodium dinaphthyl methanesulfonate), and made up to 100 ml with water, corresponding to a concentration of 1 g of commercial dye strength ( dispersion ratio ZT: ASK: dispersant = 1:: 0.125: 1.375) in 100 ml of water as per test drop and filter conditions.

Evaluation results:

(a) Control test without addition of dispersant

KT _S = 3-4 KT _V = 3-4 FT _V = 3-4

(b) with the addition of sodium dinaphthyl methane disulfonate

KT _S = 3-4 KT _V = 4 FT _V = 4

c) with the addition of a dispersant according to the invention

KT _S = 4 KT _V = 4-5 FT _V = 4-5

Example 2

5.0 g of the basic dye type O-Orange E-R was ground with 1.0 g of Ligraf ASK for drop test P 3-4. After filtering off and washing with Balotin, 335 ml of dispersion were obtained. To the collected 30.48 ml containing 0.546 g dry matter was added 0.454 g of the test dispersant and made up to 100 ml, corresponding to approximately 1 g of the commercial dye strength dye (ZT:: ASK dispersant ratio: 1: 0.2: 1 dispersant) (2) in 100 milliliters of water.

Evaluation results:

(a) a control test without the addition of a dispersant

KT _S = 3 4 _KT = _FT = 4

(b) a control test with the addition of dinaphthyl methane disulfonate

KT _S = 3-4 KT _V = 4 FT _V = 4

c) a control test with the addition of a dispersant according to the invention

KT., - 4 KT, = 5 FT _V = 5

The dispersion efficiency and stability of the dispersions were further tested by grinding Ostacet dye pastes with 0.04-0.08 parts of dispersant and 1 part of pigment, calculated on dry weight. In order to be able to compare efficiency, grinding was performed under the same conditions, with a 35% concentration of the milled slurry and a corundum disk peripheral speed of 6.3 m / sec, with the same number of slurry runs.

EXAMPLE 3 A part of Ost-Yellow SE-LG in the form of a 35% paste was milled in a disk mill with 0.04 parts of a sodium dinaphthyl methane disulfonate dispersant. After grinding the pigment was washed with water and made up to 1% dispersion solution.

In the same way, a 1% solution of Ostacet Yellow SE-LG with a dispersant according to the invention was prepared. The prepared samples were monitored for stability of dispersions after 7 and 14 days by drop test.

Evaluation results:

a sample with dinaphthyl methane disulfonate b) a sample with dispersant according to the invention

1. after grinding

CC _and 4-5 CC _b · - 5

2. after 7 days

CC _a - 3 - 4 CC _b = 4-5

3. after 14 days

KT _a = agglomerates KT _b = 4

EXAMPLE 4 Part O-Acetate SE-LG as a 30% paste was milled in a corundum grinder with 0.05 parts of a sodium dinaphthyl methane disulfonate dispersant. After grinding, the pigment was rinsed with water and made up to 1% with water.

In the same way, a dispersion was prepared using the dispersant of the invention. The solutions prepared in this way were monitored for stability of the dispersion after 7 to 14 days by drop test.

Evaluation results:

and a sodium sample dinaftylmethanedisulfonanem b - sample s dispersant according to the invention 1. after grinding KT _a = 4-5 CC _b = 5 2. after 7 days KT _and - 4 CC _b = 5 3. after 14 days KT _and - 3 4 KT _b = 4-5 Example 5

A portion of the O-scarlet scarlet E-G was milled in the form of a 35% paste in a corundum mill with 0.08 parts of a sodium dinaphthyl methane disulfonate dispersant. After grinding, the dispersant paste was diluted with water to a 1% dispersion in water solution. In the same manner, a sample of Ostacetal scarlet E-G was prepared with the dispersant of the invention.

Claims (1)

Subject OF THE INVENTION A dispersant comprising 92 to 97 parts by weight of the sodium salt of 2-naphthalenesulfonic acid polycondensate with formaldehyde of the general formula wherein η-1 to 8, 5 to 7 parts of sodium sulfate and water.