CS238764B1 - Powder dispersant mixture for plastic milling of phthalocyanine pigments and process for its preparation - Google Patents

Abstract

Powdered dispersion mixture for plastic grinding of phthalocyanine pigments based on inorganic salt and organic liquid, consisting by weight of 95 to 60% inorganic salt with a particle size of 3 to 40 microns and 5 to 40% organic liquid adsorbed on their surface from the set including glycols, their polymers, optionally isomers and/or glycerin and a method for producing a powdery dispersion mixture for plastic grinding of phthalocyanine pigments by drying an aqueous solution of organic liquids from the set including glycols, their polymers, optionally isomers and/or glycerin and inorganic salts in a pneumatic dryer at temperatures passing through air or inert gas from 50 to 400 °C.

Description

The invention relates to a powdery dispersion mixture for plastic grinding of phthalocyanine pigments and a method of its preparation.

A method of obtaining mixtures for plastic grinding of organic pigments is known by mechanically mixing a preliminary finely ground mineral salt soluble in water and organic liquids miscible with water in which the said salt does not dissolve. Preliminary grinding of mineral salt to the desired fineness is carried out mechanically using various dispersing devices /dismembrators, disintegrators, jet mills, etc./. The efficiency of plastic grinding of organic pigments, especially phthalocyanine ones, is largely determined by the particle size of the mineral salt and increases when using a salt with a very small particle size.

The preparation of the dispersion mixture for plastic mixtures is carried out by mixing the inorganic salt and the organic liquid directly in the device for plastic grinding of the organic pigment. After the plastic grinding process is completed, in the presence of organic pigments, the reaction mixture is diluted with water and the organic liquid /reaction medium/ is separated from the pigment in the form of an aqueous solution by filtration or centrifugation. The separated aqueous solution of the mineral salt and the organic liquid are regenerated, while the mixture of water and organic solvent is removed from the mineral salt by drying and mechanical grinding, converting the separated salt back to the desired dimensions and returning it to the process. The mixture of water and organic liquid is returned to the process.

The disadvantage of the known method of preparing a dispersion mixture for plastic grinding of organic pigments is the operational difficulties and high costs of the process of separating the ternary mixture of water-organic liquid-mineral salt, which includes evaporation of solutions, filtration, drying and subsequent grinding of the mineral salt and rectification. A particularly demanding technical stage is the recovery of finely ground mineral salt with a very small particle size. The known method requires significant investment costs and demands on labor and energy.

A powdery dispersion mixture for plastic grinding of phthalocyanine pigments and a method for its preparation have now been found, which partially eliminate the above-mentioned shortcomings.

A powdery dispersion mixture for plastic grinding of phthalocyanine pigments based on an inorganic salt and an organic liquid from the group comprising glycols, their polymers, or isomers and glycerin, according to the invention consists of 95 to 60% by weight of sodium chloride with a particle size of 3 to 40 microns and 5 to 40% of an organic liquid adsorbed on their surface.

The method of producing a powder dispersion mixture for plastic grinding of phthalocyanine pigments according to the invention consists in drying an aqueous solution of organic liquids and inorganic salt in a pneumatic dryer at temperatures of air or inert gas from 90 to 400 °C, whereby water is removed and a finished powder mixture containing 95 to 60% of finely dispersed inorganic salt is obtained, which contains adsorbed organic liquid and thus enables single-stage dosing into the grinding process of organic pigments. Another advantage of the powder dispersion mixture according to the invention is that the process of its preparation itself is carried out in one device, the grinding and classification stage of the mineral salt is eliminated, the regeneration of the organic solvent is eliminated, investment and energy costs are reduced and the number of operating personnel is reduced.

The examples below illustrate the method of preparing the powder dispersion mixture according to the invention and its use in plastic grinding of phthalocyanine pigments.

Example

A solution of a ternary mixture of sodium chloride, polyethylene glycol with a molecular weight of 600 - water with a weight ratio of 14 : 6 : 80 was dried in a spray dryer with centrifugal spraying at a temperature of the thermal medium at the inlet of 200 °C and at the outlet of 80 °C. Water was removed in the drying process, and a white, free-flowing powder consisting of a mixture of NaCl and polyglycol with a molecular weight of 600 in a weight ratio of 70 : 30 was formed. The average size of the NaCl particles was 4 to 6 micrometers with a very narrow particle size range. The dispersion mixture was tested in the process of plastic grinding of copper phthalocyanine. The quality of the pigment obtained corresponded to the quality of the pigment obtained by the previously known process.

Example 2

The procedure is the same as in Example 1, but a fluidized bed dryer is used as the drying device. The dispersion mixture obtained has an average NaCl particle size of 8 to 12 micrometers with a narrow particle size range.

Example 3

The procedure is the same as in Example 1, but a film rotary evaporator with mechanical removal of the dried dispersion mixture, operating both at atmospheric pressure and at a pressure lower than atmospheric, is used as the drying device.

Example 4 and 5

The method is analogous to that in Example 1, but as the inorganic salt, corresponding amounts of sodium sulfate and sodium carbonate are used at the same ratio of inorganic salt, polyethylene glycol with a molecular weight of 600 and water.

Example 6 to 13 Example number Organic liquid Inorganic salt Ratio of organic liquid to inorganic salt

6 triethylene glycol NaCl 1-:4 7 polyethylene glycol with mol. weight 300 NaCl 1:3 8 ' polyethylene glycol with mol. weighing 1,000 NaCl 1:2.5 9 polyethylene glycol with mol. weighing 1,500 NaCl 1:2.4 10 polyethylene glycol with mol. weighing 6,000 NaCl 1:2 11 glycine and polyethylene glycol with mol. weight 600 On ₂ S0 ₄ 1:4 12 glycerin and polyethylene glycol with a molecular weight of 600 Na ₂ C0 ₃ 1:2.7 13 Γ mixtures of solvents from the mixture of NaCl, NaSO^ arbitrarily in the from 7 to 12 in any order- and soda in any limit from 1:2 any ratio or any ratio or arbitrary to 1:6 solvent from examples 7 to inorganic salt from prlkl. 12 7 to 12

The procedure can be similar to that in Examples 1 to 8 if the drying process is carried out in an inert atmosphere, preferably nitrogen.

Example 15

The application of the mixture prepared according to the previous examples in the process of grinding organic pigments is carried out by weighing into the paddle mixer high-percentage copper phthalocyanine, obtained from continuous production in a dry manner according to Czechoslovak AO 290 288/1 mass part/ and a powder dispersion mixture /4 mass parts/, consisting of very fine sodium chloride and polyethylene glycol according to the example. The powder components are kneaded for 15 to 20 minutes at a temperature of 60 to 65 °C. During this time, the mass acquires suitably viscous plastic properties and the usual method of plastic grinding is then followed. The total time of plastic grinding, the corresponding costs of electricity are 30% less, the technological process is simpler and has less demands on active operator time than the previously known method.

A blue phthalocyanine pigment of beta-modification is obtained, analogous in properties to the pigment obtained by a previously known process.

Example 16

The procedure is similar to that in Example 15, except that the copper phthalocyanine is a low-chlorinated copper phthalocyanine containing 4.2 percent by weight of organically bound chlorine. This procedure yields a blue phthalocyanine pigment, stable in aromatic solvents, with a greenish tint. The pigment is suitable for coloring polyvinyl chloride used in the production of cables.

Example 17

The procedure is similar to that in Example 15, but the mixture from Example 3 is used as the dispersing mixture, and copper phthalocyanine is used, obtained in a known manner in a trichlorobenzene environment from a mixture of 96 parts by weight of phthalic anhydride and 4 parts by weight of 4-tert.butylphthalocyanine. The obtained blue phthalocyanine pigment is stable in aromatic solvents with high coloring power and has a distinct red hue. This pigment is particularly advantageous for the printing industry. A similar procedure can be used if, instead of copper phthalocyanine obtained in a trichlorobenzene environment, phthalocyanine prepared by a dry method from a mixture of 96 parts by weight of phthalic anhydride and 4 parts by weight of 4-tert.butylphthalocyanine is used.

Example 18

36 parts by weight of high-percentage copper phthalocyanine, obtained by the method of continuous baking without solvents, 4 parts by weight of a deflocculating agent of the formula Pc1SO6NHCH6CH3OH), where Pc denotes the remainder of the copper phthalocyanine, and 160 parts by weight of the dispersion mixture prepared according to Example 9 are weighed into a paddle mixer. The mixture of components is subjected to plastic grinding, as indicated in Example 15. The obtained blue phthalocyanine pigment of beta-modification does not flocculate in paint systems and is suitable for use in air-drying enamels.

Example 19

F

37 parts by weight of copper phthalocyanine, obtained by condensation of 95 mol % phthalic anhydride in a continuous solvent-free process, and 3 parts by weight of a deflocculating agent of the formula Pc1CH2-NtCH2CH2OH), 5, where Pc denotes the remainder of Cu ftc., and 160 parts by weight of the dispersion mixture according to Example 9 are weighed into a paddle mixer. The mixture of components is subjected to plastic grinding, as indicated in Example 15. The obtained blue phthalocyanine pigment is stable to aromatics, does not flocculate in toluene dyes for gravure printing, has an intensely reddish hue and high tinting strength.

Example 20

60 parts by weight of high-percentage copper phthalocyanine, purified by treatment with 5% sulfuric acid and containing 14.5 chlorine atoms, which was obtained from phthalic anhydride by any known method, and 170 parts by weight of the dispersion mixture obtained according to Example 1 are weighed into a paddle mixer. The dry powdery components are mixed at a temperature of 70 to 80 °C for 15 to 25 minutes until a plastic viscous mass is formed.

The plastic grinding process is continued for 3.5 hours at the same temperature. The obtained mass is diluted in a kneader with water, removed, filtered, washed from the components with a dispersion mixture and dried. The obtained green phthalocyanine pigment is identical in properties to the pigment obtained by plastic grinding with gradual dosing of all components. The total time of the dispersion process (and the resulting energy and labor costs) is reduced by 25 to 40% compared to known methods. The process is technologically more advanced and easier to operate.

Example 21

Analogously to Example 20, but as the highly chlorinated copper phthalocyanine, purified copper phthalocyanine containing 16 chlorine atoms in the molecule and obtained using tetrachlorophthalodinitrile is used. The obtained green phthalocyanine pigment exhibits, in terms of coloristic properties, such parameters as the pigment obtained by plastic grinding at small doses of components, while the energy and labor costs are reduced by 25 to 40%, compared with the known method.

Claims (2)

Powder dispersing mixture for plastic grinding of phthalocyanine pigments based on inorganic salt and organic liquid, characterized in that it consists of 95 to 75% by weight 60% of an inorganic salt having a particle size of 3 to 40 microns and 5 to 40% of their surface absorbed organic liquids selected from the group consisting of glycols, their polymers, optionally isomers and / or glycerin. 2. A process for the production of a powder dispersion composition for plastic grinding of phthalocyanine pigments, characterized in that an aqueous solution of organic liquids selected from the group consisting of glycols, their polymers or isomers and / or glycerol and inorganic salts is dried in a pneumatic dryer at temperatures gas from 50 to 400 ° C.