CS232424B1 - Processing of dyed anorganic pigment and filler - Google Patents

Abstract

Dyed inorganic pigments and fillers titanium dioxide. litopone zinc oxide, blanc, iron oxide, silica, kaolin a chalk, additionally coated with organic colored pigments that are fixed on their surface using metal hydroxides and / or silica, They are prepared so that they become organic colored the pigment is applied at 60 ° C on the backing material and fasten with metal hydroxides and / or oxide silica. The adjusted product does not filter, wash, and apply either in the form of paste into water-based paints, or dried at a temperature of up to 160 ° C, it is applied slowly and powdered to all types of paint and plastic materials and other types of industrial products. This makes it possible to extend the color range inorganic pigments and fillers and substantially beautify them while preserving their original Properties

Description

Inorganic pigments are an important component of paints, printing inks, plastics, man-made fibers, paper and rubber and many other products.

They are characterized by particularly high hiding power, coloring ability, weathering resistance and lightfastness. They give the products not only a nice appearance, but protect them from the effects of the weather and the environment at all, thereby extending their service life.

However, they cannot be produced in such a wide range of colors and in various shades as organic color pigments. Some of them, eg yellow chromium and cadmium pigments, lose their importance for practice because they are hygienically harmful.

In contrast, organic color pigments are generally poorly weathered and light stable and have relatively lower opacity.

By combining the good properties of both types of pigments, it is possible to expand the color range of inorganic pigments and substantially refine them while maintaining their pigment properties.

Until now, references have been found in the literature only to dyeing pearl pigments with foliar structure. E.g. DP 2429762 Farbstoffhaltige Glanzpigmente, wherein said pearlescent pigments are dyed with water-soluble organic dyes using aluminum lacquers. The method of AO 207 949 is simpler where water-soluble cationic and anionic dyes precipitate onto the surface of the nacreous pigment with a silica gel. In a similar manner, the inorganic titanium dioxide pigments of BF, 448055 are colored using a resin.

The most preferred method of treating inorganic pigments and fillers is to apply colored organic pigments to white, colored and filler inorganic pigments in approximately the same manner as disclosed in the author's certificate No. 224 792 Foliar color pigments and a process for their production.

The invention relates to colored inorganic pastes and pigments based on titanium dioxide, lithopone, zinc oxide, blanc-fixe, iron oxide, silica, kaolin and chalk, which are additionally treated with organic color pigments which are fixed to their surface by metal hydroxides, preferably aluminum hydroxide and silica gel, or mixtures of both hydrated aluminum and silicon oxides.

The essence of the preparation of the colored inorganic pigment and filler consists in mixing the aqueous suspension of these substances with stirring at 50 to 80 ° C with an aqueous dispersion of the organic color pigment and stirring for 15 minutes. Next, the metal salt solution is metered in over 5 minutes, stirred for 15 to 20 minutes, and then the suspension is neutralized with alkaline hydroxide for 20 to 30 minutes and stirred for a further 30 to 60 minutes. The treated product is filtered, washed and applied either as a paste to aqueous paints or dried at a temperature of up to 160 ° C, ground and powdered in all kinds of paints, plastics and other industrial products.

Alkaline silicate may be used instead of the metal salt and the suspension adjusted to pH 5-7 with mineral acid.

It is also possible to precipitate the metal hydroxide and the silica gel by first dosing the metal salt solution, then the alkali silicate solution, and finally neutralizing it with an alkaline hydroxide solution to a pH of 7 to 7.5.

In this way, colored inorganic pigments and fillers can be prepared in pastes or in powder, preferably with 1 to 6% of an organic color pigment in hitherto unattainable colors and shades. White inorganic pigments are particularly well colored. He will

J Paste with a very clear tone in different colors and shades. The treated inorganic pigments can completely replace inorganic colored pigments such as chrome and cadmium yellow, chrome green, ultramarine, cobalt blue, malachite green, antimony vermilion and other color pigments.

Also, ferric pigments produced by both thermal and precipitation processes, both red and yellow, can revitalize and enhance their color while removing the gray tone that is typical of these pigments. In the case of red thermal ferric pigments, mixtures of ferric pigment and titanium white have proven useful in dyeing.

Dyed inorganic pigments are characterized by good hiding power, resistance to weathering and light stability. The organic color pigment is firmly homogeneously bound to the surface of the inorganic pigment by metal hydroxide and silica gel, which protects it against thermal and light radiation and thereby substantially affects its color stability. Also, the processability of the dyed inorganic pigment in various binder systems is easier, while the organic pigment does not separate during processing.

The following principles apply to the preparation of high-quality colored inorganic pigments and fillers: Generally, 1 to 10 are used. 6% colored organic pigment per product weight.

If the excess is too large, a portion will remain in suspension and will not precipitate on the surface of the inorganic pigment. Also, the organic color pigment particles should not exceed 0.5

Inorganic pigments with a high specific surface area receive more organic pigment than pigments with a small specific surface area. The metal salts from which the hydroxides can be precipitated can be any soluble salts which can be hydrolyzed with bases or acids. Particularly suitable are aluminum salts which can be hydrolyzed with bases, or alkali aluminates which are hydrolyzed with acids. Any alkali salts, sodium, potassium or ammonia can be used in the precipitation. When using alkaline silicate, precipitation with dilute mineral acid to pH 5-7 is preferred. The precipitation must be carried out in such a way that the metal hydroxide and the silica gel are quantitatively precipitated on the substrate and the colored organic pigment particles are deposited simultaneously with the metal hydroxide and the silica gel. The colored organic pigment particles interfere with the precipitate and are therefore firmly fixed to the substrate. Upon completion of the precipitation process, the pigment obtained is treated in the usual manner by separating it from the reaction mixture, washing it with water and obtaining it in the form of a paste or drying it and grinding it.

The proportion by weight of the precipitated metal hydroxide is different and depends on the base material used, in particular on its fineness and on the fineness of the organic color pigment and also on the desired properties of the finished product. The ratio of organic dye pigment to metal hydroxide and silica gel is most preferably from about 2 to about 1: 5.

The best color organic pigments were the color pigments produced at the East Bohemian plant in Rybitví and sold under the trademarks Spoloxyl and Versatine azo dyes. They are insoluble in water and in common organic solvents. Their advantage is good stability, especially in light. They are mixed in any proportion with water and are therefore used wherever powder pigments do not satisfy their high water repellency.

The chemical composition of the pigments used is an example:

Coxyl blue B - Cu-phthalocyanine

Versatine Red KGL - 3-hydroxy-4- (2,5-dichlorophenylazo) -2-naphthoic acid anilide

Cooxyl yellow G - 2- (2-nitro-4-methylphenylazo) -3-hydroxycrotonanilide

Cooxyl Green BG - a mixture of 2- (2-nitro-4-methylphenylazo) -3-hydroxycrotonanilide and Cu-phthalocyanine

Other color-miscible, water-insoluble, organic, water-soluble, polar and non-polar solvents can also be used for coloring inorganic pigments and fillers.

The progress achieved by the invention is that in this way it is possible to produce high-quality colored inorganic pigments in all colors and shades by a simple, yet undescribed process.

Example 1

150 g of untreated titanium dioxide of the rutile type is dissolved in distilled water to a volume of 1000 ml, heated to 60 ° C and adjusted to pH 8 with 10% sodium hydroxide solution with stirring. The suspension is then dispersed with an efficient stirrer for 10 minutes. Next, 15 ml of a 20% Cu-phthalocyanine suspension is added and stirred slowly for 15 minutes. The temperature of the slurry is maintained throughout the process at 60 ° C. Then 127.5 ml of 47 g alumina solution / l are added over 5 minutes, followed by a 20 minute dwell. Thereafter, 23.5 ml of a 64 g silica / l waterglass solution are metered in over 5 minutes and mixed for 20 minutes. Within 20 minutes, the suspension is neutralized with a 10% sodium hydroxide solution to pH 7, followed by a further 20 minutes with stirring. The product obtained is filtered, washed with demineralized water at 60 DEG C., warmed to 160 DEG C. and dried. The pigment is blue in color and contains 93% titanium dioxide, 4% alumina,% silica and 2% organic pigment.

Example 2

The procedure of Example 1 except that the pigment obtained is filtered, washed, but not dried.

The color paste has a deep blue color. It contains 50% titanium dioxide, 4% alumina, 1% silica, 2% organic pigment and 43% water.

Example 3

The procedure of Example 1 except that zinc white was used instead of titanium white and 3-hydroxy-4- (2,5-dichlorophenylazo) -2-naphthoic acid anilide was used instead of Cu-phthalocyanine. The pigment obtained is pink in color and contains 93% zinc oxide,% alumina, i% silica and 2% organic pigment.

Example 4 r

The procedure of Examples 1 and 3 except that the product was filtered, washed, but not dried.

The color paste has a deep pink appearance and contains 51% zinc oxide, 4% alumina, 1% silica, 2% organic pigment and 42% water.

Example 5

The procedure of Example I was followed with the exception that thermal red was used instead of titanium white and 1- (2-chloro-4-nitrophenylazo) -2-naphthol was used instead of Cu-phthalocyanine.

The pigment obtained has a reddish brown color with a slight orange hue. It contains 93% iron oxide, 4% alumina, 1% silica and 2% organic pigment.

Example 6

The procedure of Example 5, except that a 3: 1 mixture of thermal red and titanium white was used.

The pigment obtained has a bright red color with an orange hue. It contains 70% iron oxide, 23% titanium dioxide, 4% alumina, 1% silica and 2% organic pigment.

Example 7

The procedure of Example 1 except that kaolin was used instead of titanium white.

The filler obtained is blue in color and contains 93% kaolin, 4% alumina, 1% silica and 2% organic pigment.

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EXAMPLE 8 Example 1 except that lithopone is used instead of titanium dioxide and 2- (2-nitro-4-methylphenylazo) -3-hydroxycrotonanilide is used instead of Cu-phthalocyanine. 6.

The pigment obtained is yellow in color and contains 94% lithopone, 4% alumina and 2% organic pigment.

Example 9

The procedure of Example 1 except that blanc-fixe was used instead of titanium white and a mixture of 2- (2-nitro-4-methylphenylazo) -3-hydroxycrotonanilide and Cu-phthalocynin was used instead of Cu-phthalocynin. The aluminum sulphate was no longer added and neutralized to pH 6.

The filler obtained is a deep green color and contains 97% blanc-fixe, 1% silica and 2% organic pigment.

He did

The procedure of Example 1 except that silica was used instead of titanium white.

The treated product is filtered, washed and dried. Color paste has a deep blue color, and _R contains 49% silica, 4% alumina, 2% of an organic pigment and% water.

Example 11

The procedure of Example 1 except that a chromium sulfate solution was used in place of the aluminum sulfate solution.

The pigment contains 93% titanium dioxide, 4% chromium oxide, 1% silica and 2% organic pigment.

Example 12

The procedure of Example 1 was followed except that 2- (2-nitro-4-methylphenylazo) -3-hydroxycrotonanilide was used in place of Cu-phthalocyanine and ferric chloride solution was used in place of the aluminum sulfate solution.

The pigment contains 93% titanium dioxide, 4% iron oxide, 1% silica and 2% organic pigment.

Claims (5)

SUBJECT OF THE INVENTION Dyed inorganic pigment and filler coated with an organic colored pigment, metal oxide and / or silica, characterized in that it comprises 70 to 96.9% by weight of a core selected from the group consisting of titanium dioxide, lithopone, zinc oxide, blancfix, omid 0.1 to 10%, preferably 1 to 5%, of an organic color pigment and 2 to 20% of a metal oxide and / or silica, based on the weight of the finished product. 2. A process for the production of a colored inorganic pigment and filler according to claim 1, characterized in that the aqueous core suspensions of 100-300 g / l are mixed with stirring at 60 [deg.] C. with an aqueous 20% dispersion of organic color pigment. The solution is neutralized to neutral with alkaline or ammonium hydroxide for 30 to 60 minutes, and the product is filtered, washed, dried and ground. 3. The process of claim 2, wherein after addition of the metal salt, a 20% solution of alkali silicate is added over a period of about 5 to about 0 minutes, and the suspension is rendered neutral with alkaline hydroxide or ammonia within 30 to 60 minutes. 4. The process of claim 2 wherein a 20% alkali silicate solution is metered in instead of the metal salt, and the suspension is neutralized to neutral with 10 to 20% acid over 30 to 60 minutes. 5. Process according to claim 2, 3 or 4, characterized in that the treated product is not dried, it is only filtered and washed to form a paste.