CH618459A5 - Process for the formulation of copper phthalocyanine - Google Patents

Description

618459

2nd

PATENT CLAIMS

1. A process for the formation of copper phthalocyanine (CuPc), characterized in that 1 part by weight of raw CuPc material without prior boiling with 0.1-20 parts by weight of a water-soluble or inorganic, soluble in aqueous acids or bases or organic salt and 0.3-5 parts by weight of an organic or inorganic solvent or solvent mixture which does not substantially dissolve either pigment or salt, kneads and then removes the synthesis by-products, the salt and the solvent by boiling out.

2. The method according to claim 1, characterized in that one uses a raw CuPc with a maximum CuPc content of 95%.

3. Process according to Claims 1 and 2, characterized in that the raw CuPc has a shear rate of 300 to in a continuously working kneading apparatus

Subjects 20,000 sec-i over a period of 10 seconds to 15 minutes, the amount of solvent being such that the energy consumption of the kneading is between 0.4 and 50 kWh / kg of pigment penetrated.

4. Formed CuPc pigment, produced by the process according to claim 1.

When manufactured using various baking and solvent processes, copper phthalocyanine (CuPc) is usually obtained in an impure form that is unusable as a pigment. The raw materials still contain the by-products formed during the synthesis and the pigment particle size distribution is not in the range that is favorable for achieving optimal pigment properties.

In order to convert the raw material into a suitable pigment form, it was previously necessary to boil the raw material first with acids, possibly also with bases, in order to largely remove the impurities and then to increase the particle size and shape to the range favorable for the pigment properties convict.

The previously known methods therefore have the disadvantage of requiring a large number of individual operations, so that the methods are very time-consuming and costly.

For example, a common manufacturing method includes the following process steps:

1. Synthesis of CuPc in an indifferent organic solvent

2. Removal of the solvent

3. Boil out the raw product with dilute mineral acid

4. Drying

5. Grind

6. Forming, for example by salt milling in the ball mill according to US Pat. No. 2,556,730

7. Wash out the salt with water or dilute mineral acid

8. Drying

9. Grind.

There was therefore a need for simpler processes for the production of CuPc in pigment form.

If one now tries to combine the boiling out of the crude pigment and the washing out of the salt after the salt grinding in order to save process steps 4, 5 and 7, by directly salt-milling the synthesis product without boiling out and then removing the impurities with dilute acid, one obtains a weak-color and dull β-CuPc pigment, which did not omit the quality of the products in the manufacture of process steps 4, 5 and 7.

Surprisingly, it has now been found that a copper phthalocyanine (CuPc) of excellent pigment quality with simultaneous saving of process steps according to the invention can be obtained if 1 part by weight of raw material without previous boiling is obtained directly with 0.1-20 parts by weight, preferably 1-10 parts, a water-soluble, or in aqueous acids or bases soluble, inorganic or organic salt and 0.3-5 parts by weight, preferably 0.5-3 parts by weight of an organic or inorganic solvent or solvent mixture, which does not significantly dissolve pigment or salt, kneads and then removes the synthesis by-products, the salt and the solvent by boiling. The method has proven itself in particular in the case of crude CuPc with a maximum CuPc content of 95%, i5 preferably 90%.

This salt kneading can be carried out batchwise or continuously.

A particularly preferred salt kneading process is characterized in that a mixture of raw material, a salt and a solvent is used in a continuously working kneading apparatus with spatially separated possibilities for adding liquid with a shear rate of 300 to 20,000 sec-i, preferably 500 - 5,000 sec- i over a period of 10 seconds to 15 minutes at temperatures between 100 25 and 300 ° C, the amount of solvent being measured so that the energy consumption of the kneading is between 0.4 and 20 kWh / kg of penetrated pigment.

Two-shaft and four-shaft kneading screws are suitable for the preferred salt kneading process, as are single-shaft kneading screws which have kneading bars of a suitable geometric shape sitting on the housing and which can also perform oscillating movements in addition to rotation.

For example, the kneading screw ZSK from Werner u. Called Pfleiderer.

The particularly preferred continuous salt kneading process has over known salt kneading processes (US Pat. No. 2,982,666 and German Offenlegungsschrift 1,919,496), in which, however, crude CuPc pigments were always used which were already boiled out with acid, dried and ground were the advantage of delivering pigments with a more uniform crystal shape in a narrower grain size spectrum with shorter residence times. These advantageous properties are particularly noticeable in the flowability, dispersibility, color strength, light and weather fastness.

The temperatures in at least some of the kneading zones are between 120 and 350 ° C, preferably between 160 and 280 ° C.

Suitable solvents are those whose boiling point 50 is above 140 ° C. and which are liquid under the kneading conditions. Particularly suitable are those which are at least slightly soluble in water or dilute aqueous acids or bases, such as polyhydric aliphatic alcohols, e.g. Ethylene glycol, propylene glycol or glycerin, ethanolamines, 55 phenols, anilines, polyethylene glycols, propylene glycols, monoesters and monoethers of polyethylene glycols and polypropylene glycols, polyethylene amines, N-alkylated and N-hydro-xyalkylated polyethylenestimines t-disubated Anilines, the substituents being alkyl, hydroxyalkyl, 60 alkoxyalkyl, polyalkoxyalkyl, alkylaminoalkyl and polyalkylaminoalkyl groups, the polyalkoxy and polyalkylamine parts of which are derived from ethylene oxide, propylene oxide, ethylene imine or propylene imine. Silicone oils, phosphoric acid amides and esters and molten salts 65 of salts and salt mixtures, for example aluminum chloride, zinc chloride, may also be mentioned.

Suitable inorganic and organic salts include, for example, sodium chloride, potassium chloride, sodium sulfate,

3rd

618 459

Zinc chloride, aluminum chloride, aluminum sulfate, calcium carbonate, sodium acetate, potassium sodium tartrate, calcium acetate or sodium citrate.

Particularly suitable solvents are polyhydric alcohols and their partial ethers.

example 1

A 125 1 AP Conti reactor from List, Pratteln / Switzerland, is used per hour

104 kg phthalic anhydride

168 kg of urea

20.1 kg of basic Cu carbonate with 54-56% Cu and 0.8 kg of ammonium molybdate were added. The main shaft is driven at 100 rpm. rotated and the temperature of the heating oil adjusted so that the reaction mass in the last third of the reactor reaches a temperature of 225 ° C. The raw material thus obtained had a CuPc content of approx. 75%.

90 g of this raw product

270 g NaCl and

60 ml of aniline are kneaded in a 250 ml four-shaft kneader at 120-135 ° C. for 1 h, cooled and boiled 2 × 2 h with 2.515% hydrochloric acid, washed acid-free with hot water and dried at 80 ° C.

The pigment thus obtained, which is completely in the β-modification, has high color strength and brilliance after incorporation in an offset binder on a plate grinder or in a toluene gravure binder.

Example 2

A kneading screw of the type ZSK-530 from Werner and Pfleiderer, Stuttgart, which is shown with a kneading stock as shown in Fig. 3, 10.2 kg / h of the raw CuPc pigment, which is given in Example 1, produced was and 41 kg / h rock salt supplied. About 5.9 kg / h, via nozzle 2 0.935 kg / h and via nozzle 3 1.25 kg / h diethylene glycol are metered in via the feed nozzle 1. The screw speed is increased to 295 rpm. adjusted and the larger Diethylenglykolmen-ge adjusted so that the power consumption of the kneading screw is 28 kW. The entire length of the apparatus is cooled with 85 ° C hot water at a flow rate of approx. 10001 / h. The emerging plasticine has a temperature of approx. 160 ° C.

100 g of the emerging plasticine are boiled out twice with 2.5 kg of 5% hydrochloric acid for two hours, suction filtered while hot, the presscake is washed acid-free with water and dried at 80.degree.

The β-modification CuPc pigment obtained in this way showed high color strength and brilliance in offset and toluene intaglio binders, with good flowability and dispersibility at the same time.

5

Example 3

A 125 l AP Conti reactor from List, Pratteln / Switzerland, produces 71 kg phthalic anhydride and 116 kg urea per hour

18.3 kg CuCl2 (anhydrous) and 0.35 kg MoOg added. The main shaft is at 10 rpm. rotated and the temperature of the heating oil adjusted so that the reaction i5 mixture in the last third of the reactor reaches a temperature of 240 ° C. The reaction mixture is boiled twice in 10 times the amount of 5% hydrochloric acid, filtered hot, washed acid-free with hot water and dried at 100.degree. The amount of boiled raw CuPc 20 thus obtained corresponded to a yield of 80% of theory, based on phthalic anhydride.

The crude CuPc obtained in this way still has to be subjected to a primary formation by known processes, such as those described in the patent literature, such as salt milling, solvent bead milling or salt kneading, in order to be converted into the pigment form of the greenish-blue ß modification. or a sulfuric acid paste in order to be converted into the reddish-blue «modification.

When using the formation method according to the invention, the usual boiling out twice with hydrochloric acid is eliminated.

Example 4

35 110 kg phthalic anhydride 31 kg 4-chlorophthalic acid 31 kg CuCl2 200 kg urea and 40 1 kg ammonium molybdate are fed to a 125 1 AP Conti reactor. The experimental procedure and the working up were carried out as in Example 2. The yield was 76% based on CuCl2.

After pasting with sulfuric acid, a red-tinged-45 blue CuPc pigment of the a-modification was obtained with a chlorine content of approx. 4%, which had great resistance to aromatic solvents with regard to modification conversion and crystal growth.

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