DE2131617A1 - Pigment compositions - Google Patents

Description

TELEPHONE: COLLECTIVE NO. 225341 TELEGRAMS: ZUMPAT CHECK ACCOUNT: MUNICH 91139

BANK ACCOUNT: BANK H. HOUSES

53 / ΚΓ
Case 3-

1439 ⁺

CIBA-GEIGY A. G., Basel / Switzerland

Pigment compositions

The suitability of a pigment for dispersion in a particular medium for a particular application can take the form of rheological Properties, color strength, gloss, transparency, hue and wettability-dispersibility properties, showing the pigment in the medium. In general, all of these values can be related to the crystallographic Properties of the pigment and the surface properties of the pigment particles to a considerable extent are interdependent, are related.

It is known that the surface of organic pigment particles Can be modified by adding a "gTCTsse multitude of voir surfactants" -v solvents to the particles adsorbed or by the presence of such compounds during pigment formation. It has been found that it is possible in this way the rheological properties of the pigment and thus the degree of dispersion in printing inks and color media to change, resulting in improvements in the transparency and gloss of the pigment.

109853/1751

Another method has now been found according to which organic pigments can be given improved properties, The invention relates to a pigment composition which Particles of "a first organic pigment that are completely or are partially coated with a second organic pigment.

The invention is primarily for arylamide and diarylide pigments applicable. The former group is formed, for example, by reacting a diazotized nitroaniline with a Acetoacetarylarnide couples, the latter for example by adding tetrazotized 3,3'-dichlorobenzidine itself or a tetrazotized 3,3'-dichlorobenzidine, which in the aromatic nucleus may contain further substituents, with an acetoacetarylamide. Generally 3,3'-dichlorobenzidine is used itself used, but you can also use 3,3'-dichlorobenzidines use. For example, pigments were made from tetrachlorobenzidines. Examples of coupling agents the ν er \\ 'end et were acetoacetanilid, acetoaceto-toluidid, Acetoacet-p-toluidid, Acetoacet-o-anisidid and Acetoacet-2,4-xylidide.

Azo pigments are generally prepared by adding the diazotized component to the coupling agent in acidic aqueous solution Medium couples. After coupling, the reaction mixture is heated to the boil and the pigment is worked up. Two parameters of the resulting pigment are important the average primary particle size and the average Crystallite size within each particle and it was found that better rheological properties were obtained can if the pigments are incorporated into ink media will have a large average crystallite size, which is in fact the average primary Approximates particle size, this being true for all average primary particle sizes of the pigment- · At the present In accordance with the invention, an inner pigment or a basic core pigment is taken for an inner core, and its surface is covered with a complete or partial coating of an

109853/1751

modified their pigment of a similar structure. Example shows lev; the pigment that can be obtained by adding acetoacet- o-anisidid with 3,3'-dichlorobenzidine couples what is in the form of smaller Crystallites are present (amorphous in X-ray powder photography), poor flow properties in printing inks, whereas the pigment obtained by coupling acetoacet- xylidide with 3,3'-dichlorobenzidine is obtained in the form of large Crystallites is present, has good flow properties. A Pigmont composition made of particles of acetoacct-o-anisidide, coupled with 3.3 '' dichlorobenzidine, coated with particles from Acetoacet-m-xylidide coupled with '3,3 · -dichlorobenzidine, combined the desirable properties of both pigments.

The pigment compositions according to the invention can be based on the following Way to be made. Make a slurry of the first pigment and then falls into this slurry the second pigment, so that part of the second pigment is preferentially precipitated on the already existing cores, i.e., the particles of the first pigment, and forms a coating thereon. It is believed that part of the second organic Pigments as they are formed during the precipitation process active on existing crystallites of the first pigment High energy points, especially at dislocation points, grows. This coating occurs even when the second pigment is only present in small proportions. That The method is particularly successful in the case of azo pigments. The first pigment can be made in a coupling solution and then the second pigment is made in the same solution without the need to use the first Isolate pigment. The same or different coupling agents can be used for the two pigments.

Evidence that the pigment core is coated can be as follows be provided. A pigment core made of Acetoacetm-xylidid, coupled with Tetrazo-3,3'-dichlorobenzidine, on treated in such a way that one must assume, according to the present invention, that a pigment coating of acetoaceto-anisidide, coupled with tetrazo-3,3'-dichlorobenzene

• - 109853/1751

idin arises, and if you look at the system at the Aufschlärninungsstufe When heated to boiling, the crystallite growth of the cores is inhibited by the pigment coating. This is done through X-ray powder photography shown »If, on the other hand, you have a physical mixture of the slurries you get, by coupling freshly made acetoacet-m-xylidide, " with tetrazo ~ 3,3'-dichlorobenzidine, and freshly made Acetoacet-o-anisidide, coupled with tetrazo-3,3'-dichlorobenzidine, mixed, i.e. a slurry that is not coprecipitated was heated to the boil, so one cannot inhibit the growth of the crystallite particles in the Watch core.

The effect of the present invention is that a coating or a partial coating of a second organic pigment is formed on a core of a first pigment. The optical properties of the pigment core are not changed much because the optical properties of the composition are somewhere in between the properties of each pigment. A composition is obtained which has the optical properties of a first pigment but the surface properties of a second pigment when the pigment used for the coating is only present in small amounts. In the case of Monoeizopigmenten as arylamide yellow compounds, can be the core pigment by ANNB represent _r wherein A is the diazo component and the coupling component B -bedeuten.- This - pigments can cover either

Ii) a monoazo pigment represented by the formula A-N = K-D where D is a coupling component different from that used in the core pigment was used, or

2.) a monoazo pigment represented by the formula C-N = N-B where C is a diazo component which differs from that which was used in the core pigment, differs, or

3.) a monoazo pigment represented by the formula CN = ND, in which both the diazo component and , - r 109853/1751

-. 5 -

the coupling component differs from the corresponding components used in the core pigment.

In the case of diszo pigments, such as compounds of the benzidine yellow series, the core pigment can be represented by the formula FN = NEN = NF, where E is the tetrazo component and F is the coupling component. You can cover this with

1 ») H-N = N-E-N-N-H, where H is a coupling component that is different from that used in the core pigment was, differs, or

2.) F-N = N-G-N = N-F, where G is a tetrazo component,

which differs from that which was used in the core pigment, • or

3.) H-N = N-G-N = N-H, in which both the tetrazo and distinguish the coupling component from the corresponding components used in the core pigment. ·

It is also possible to have a monoazo pigment core with a Diazo pigment that is different from the same coupling component or another coupling component derived to cover

or the other way around. ^ j

~ E ± n-another 'point' that must be "observed", "is that," that that The effect of the core pigment is that the coating pigment adopts a special crystal modification which is different from that which the coating pigment has usually forms, differs. In such a case, the pigment that forms the core can only be a minor one Be part of the composite finished pigment. In this case, the nucleating pigment acts as a "seedling", the regulates the way in which the coating pigment is precipitated out of solution. The properties of the resulting pigment composition can be controlled in this way. For example, the stability of the pigment in color media that is obtained can

1098 53/1751 _AAO , '

by coupling m-nitro-p-toluidine with acetoacetanilide, can be improved if about 10 % of the final pigment is not, or even less, of a product that is obtained when m-nitro-ptoluidine is mixed with acetoacet -toluidine couples, used as a "seed" or core pigment. The same improvement is not observed when the products are formed at the same time using a mix-coupling method.

The pigment compositions according to the invention can be used in any Stage with any of the known solvents or surface-active Means that are used to obtain the surface properties Modifying of pigments, treated \\> ground. So can ™ the core pigment is formed in the presence of common additives . or treated with this after formation «The coating pigment can be formed in the presence of known additives will. Known treatments include surfactant treatments. Solvents and treatment with ■ Resins, with amines and with dyes, as it is in the

Patent specification. (Patent application P 21 22521.8) " ^: "

is described. \ '■

The following examples illustrate the invention without, however, restricting it. All parts and proportions are based on weight, unless otherwise stated.

Example 1 .

A tetrazo solution was made from 19.0 parts of 3,3'-dichlorobenzidine made in 450 parts of water.

16.5 parts of acetoacet-o-anisidide were dissolved in 225 parts of water containing 3.2 parts of sodium hydroxide. Were added diluted acetic acid, until the _pH value was below 7 to this solution.

The tetrazo solution was slowly added to the anisidide solution so that there was no substantial excess of the tetrazo compound at any time . By adding a 10% Na- - ■ ■ "^ 109853/1751

trium hydroxide solution, the p ^ value was kept at 4.0 to 4.5, until all of the coupling component had reacted.

16.5 parts / vcetoacet m-xylidide were dissolved in 225 parts of water containing 3.2 parts of sodium hydroxide, and this solution v / URDC added to the coupling reaction mixture, which was considered the p _H -V7ert below 7.0.

The remainder of the tetrazo solution was then allowed to run in slowly, avoiding an excess of tetrazo compound and the p "-VJert by adding 10% sodium hydroxide solution above 4.0 held.

The resulting slurry was heated to boiling for 1 hour, and the pigment composition was then isolated by filtration. The filter cake was washed until it was free from water-soluble impurities and then dried at 50 ° C.

The pigment composition was found to have an average crystallite size of 0.06 λχ as determined by X-ray powder diffraction spectra and to have excellent flow, transparency, gloss and dispersibility properties in ink media better than that of a simple physical mixture of both pigments.

If pigment preparations of acetoacet-o-anisidide, coupled with 3,3'-dichlorobenzidine, and of acetoacet-m-xylidide, coupled with 3,3 · -dichlorobenzidine were prepared in separate vessels and then mixed, heated to the boil and worked up, so the average crystallite size of the particles is below 0.03 η and the compound is amorphous according to the X-ray determination. The pigment composition thus prepared by blending the slurries has poor rheological properties when incorporated into printing ink media.

109853/1751 bad Orjgj * ial

Example 2

The procedure of Example 1 was repeated with the exception that the ratio of coupling agents was changed from equal parts by weight to a molar ratio of 4: 1 of acetoacet-o ~ anisidide to Acetoacet-m-xylidid * After the formation was the pigment composition slurry with 5% by weight dibenzyl ether heated to boiling.

The final pigment composition was isolated by filtering the slurry, washing the filter cake with -WBJSS:
dried.

Freed soluble impurities and put them at 5OC

When the final pigment composition was incorporated into a letterpress ink liquid medium, its rheological properties were found to be better than those of a known pigment formed by the coupling of acetoacet-o-anisidide and 3 _} 3'-dichlorobenzidine using the same solvent treatment. As in Example 1, the pigment composition had superior properties compared to a pigment formed by mixing the slurries.

Ex ie l 3

The procedure described in Example 2 was repeated with ~ äere "" exception that the ratio of coupling agents changed was, using a molar ratio of 1: 4 of acetoacet-o-anisidide used for acetoacet-m-xylidide.

The pigment composition formed had better gloss and transparency when incorporated into letterpress ink liquid media compared to a known pigment formed by coupling acetoacet-m-xylidide and 3 _S 3'-dichlorobenzidine with the same solvent treatment «,

109853/175 1

A physical mixture of the two pigments that are in separate Vessels had been made, mixed and refurbished did not exhibit the same gloss and "transparency" when incorporated into letterpress ink liquid media.

For j game 4

The procedure of Example 2 was repeated with the exception that was used instead of acetoacetanilide acetoacet-m-xylidide and that ratio of the coupling agent xu a molar ratio of 4: 1 was acetoacet-o-anisidide to acetoacetanilide changed '.

The resulting pigment composition had better rheological properties when placed in a letterpress ink liquid medium was incorporated, known as the pigment, which is produced by coupling of acet-o-anisidide and 3, 3 '- dichlorobenzidine with the same Solvent treatment 'had been formed. As in Example 1, the pigment composition had superior properties in Comparison with a pigment obtained by mixing the prepared slurries. Weir.

Example 5

The procedure of Example 2 was repeated except that "acetoacet-m-xylidide was replaced by an equal molar proportion of Acetoacet- o-toluidid would be replaced.

The resulting pigment composition had better rheological properties when incorporated into a letterpress ink liquid medium than a known pigment obtained by coupling acetoacet-o-anisidide and 3 _} 3 · dichlorobenzidine with the same solvent treatment. As in Example 1, the pigment composition obtained had properties superior to those of a pigment obtained by mixing the prepared slurries.

10985 3/17 51

Example 6

a) The diazonium salt of m - K ^T itro ~ p-toluidine was prepared from 44 parts of m-nitro-p-toluidine in the usual way.

52.5 parts of acetoacetanilide were slurried in 1200 parts of water at 5 to 6 ° C and 13.5 parts of sodium acetate were added added 'The ρ, value was then added with dilute acetic acid set to 4.8 to 5.0.

The diazo solution was added dropwise to the slurry with stirring over a period of 45 minutes, the p. The slurry was then heated to '80 ⁰ C with steam and filtered heißern "The thus obtained product was free of salt and dried at 50 to 55 C.

This pigment composition was incorporated into a medium for decorative colors, the color force took off the paint, the paint is stored at 60 ⁰ C.

b) The process from a) was repeated with the exception that 10 % of the acetocicetanilide was replaced by acetoacet-o-.oluidide and the two coupling agents were mixed before coupling. The Pigrnentzusarnmen.osition was in a medium for

. decorative colors incorporated as in a), and it was found that the color strength of the color decreased only slightly less at 60.degree than the color produced in a).

c) 44 parts of the diazo salt of m-nitro ~ p ~ toluidine were added known way.

4 parts of acetoacet-o-toluidide were dissolved in 0.9 parts of sodium hydroxide in 50 parts of v / water in a coupling vessel. Another 450 parts of water were then added at 5 to 6 ° C, and the p ^ value was adjusted to 5.0 with dilute acetic acid • -. * = '■'"■ 109853/1751

BATH ORIGINAL

asked »In the course of 15 minutes, the theoretical Amount of diazo salt solution of in-nitro-p-toluidine added, utn da.s toluidid to couple completely.

48.2L> parts acetoacetanilide and 13.25 parts sodium acetate were slurried in 1200 parts V / ater at 5 to G.C. and placed in the coupling vessel. The rest of the diazo solution was then added over 45 minutes and the resulting Pigment was worked up as described in a) above.

The pigment composition was incorporated into a medium for decorative paints as described in a), and man

found that the color strength of the paint was stable when stored at 60 ° C

stayed.

That in example ? The procedure described was repeated except that acetoacetanilide was used in place of acetoacet-mxylidide and that the molar ratio of coupling agents was changed to 1: 3 from acetoacet-o-anisidide to acetoacetanilide.

The pigment composition formed had a better gloss and transparency when arbeitet_w_urde in letterpress liquid media einge- M in .Vergleich..mit ... a "known pigment by coupling the acetoacet-o-anisidide and 3,3'-dichlorobenzidine with same solvent treatment.

Example 8
Clutch A

A tetrazole solution was made from 27.4 parts of 3,3'-dichlorobenzidine made in 600 parts of water.

19.4 parts of acetoacetanilide were dissolved in a coupling vessel containing 300 parts of water and 4.4 parts of sodium hydroxide.

109853/1751

^SA0

Dilute acetic acid was added to this solution until the p “value. was below 7.0.

The tetrazo solution slowly became the acetoacetanilide suspension added so that no substantial excess of the tetrazo compound was present at any time, the ρ value by adding a 10% sodium hydroxide solution at 4.0 to 4.5 was held until all of the coupling component had reacted.

22.7 parts of acetoacet-o-anisidide were in 300 parts of water, which contained 4.4 parts of sodium hydroxide, dissolved. This solution was added to the slurry at the same time as the remainder of the tetjrazo solution given in the coupling vessel, the p "value during the coupling by adding the required amount of 10% sodium hydroxide solution was maintained at 4.0-4.5. At no time was there a substantial excess of the tetrazo compound present during this second coupling.

The resulting pigment slurry was then used for 1 hour Heated to boiling, and the pigment was then isolated by filtration. The filter cake was removed from water-soluble impurities Washed free and dried at 50 ° C.

Clutch B

Its tetrazo solution was made from 27.4 parts of 3,3'-dichlorobenzidine Made in 600 parts of water. Separate pigment slurries were made as follows:

Slurry 1

19.4 parts of acetoacetanilide were dissolved in 300 parts of water, the 4th Parts of sodium hydroxide contained dissolved. Dilute acetic acid was added to the solution until the p "was below 7.

300 parts of tetrazo solution slowly added to the acet-oacetanilide suspension so added that no substantial excess of Tetrazo compound was present at any point in time, whereby

10985-3 / 1 7 5Ί "

the p _H ~ value at 4.0 to 4.5 by Zugabo a 10/0 igcn Natriuwhydroxydlösung held WUX ~ de until the entire coupling component had reacted.

Barge lä INSULATION 2

22.7 TeiJ.e Acetoacet-o-anisidid were in 300 parts of water,
which contained 4.4 parts of sodium hydroxide, dissolved. 5.0 parts of sodium acetate and 250 parts were added to the coupling kettle
Water too.

• .The remaining 300 parts of the tetrazo was slowly added with ■ the Anisididsuspension into the coupling vessel so that μ was never an essential Überschuß.an ^ etrazoverbindung 'present and the ρ "value by Zugetbe of 10% sodium hydroxide was held at 4.0 to 4.5 until all of the coupling component had reacted.

Slurries- 1 and 2 were mixed and the resulting pigment slurry was then boiled for 1 hour and then the pigment was isolated by filtration,
the filter cake was made of water soluble impurities
Washed free and dried at 50 ° C.

When the pigment composition, which was in coupling A entstan- Λ the incorporated (by the novel process), in a book ™ ink liquid medium, this was more transparent than when the pigment obtained by coupling procedure B (a method in which only a physical mixture of the pigments is created).

Example 9

Clutch A.

A tetrazo solution was made from 25.3 parts of 3,3'-dichlorobenzidine made in 500 parts of water.

17.4 parts of phenyl-3-methyl-5-pyrazolone were in 250 parts Dissolved water containing 4: 1 parts of sodium hydroxide. In the

109853 / Ί7ST

The solution was given dilute acetic acid until the p "value was below 7 lay.

The tetrazo solution slowly became the pyrazolone dilution added in a coupling vessel so that at no time a substantial excess of tetrazo compound was present, v.'O-bei the p., - value by adding 10%. Sodium hydroxide solution held at 4.0 to 4.5 v / urdc until all of the coupling component had reacted.

20.7 parts of acetoacet - o ~ anisidid were in 250 parts of water, which contained 4.1 parts of sodium hydroxide, dissolved, and this solution The solution was poured into the coupling at the same time as dilute acetic acid. respiratory vessel, whereby the p "-value was healed below 7.0",

The remainder of the tetrazo solution was then added slowly to avoid excess tetra-ro compound, and with the p "value by adding a 10% sodium hydroxide solution was held above 4.0.

The resulting pigment slurry was boiled for 1 hour heated and then the pigment was isolated by filtration. The filter cake was made by washing water-soluble impurities freed and then dried at 50 ° C.

Clutch B

A tetrazo solution was made from 25.3 parts of 3,3'-dichlorobenzidine made in 500 parts of water. This became separate pigment slurries manufactured in the following way.

Slurry 1

17.4 parts of phenyl-3-methyl-5-pyrazolone were in 250 parts Water containing 4.1 parts of sodium hydroxide dissolved. Dilute acetic acid was added to the solution until the p n value was below 7.

10985 3/175 1 sad

250 parts of tetrazo solution slowly became the pyrazolone sulfate ί, ϊοη so added that at no time was a substantial excess of tetrazo compound present, the p ^ value by adding 10% sodium hydroxide solution at 4.0 to 4.5 was held until all of the coupling component had reacted. ·

Slurry 2

20.7 parts of acetoacet-o-anisidide were dissolved in 250 parts of water containing 4.1 parts of sodium hydroxide. In the solution diluted acetic acid was added until the p ^ value was below 7.

The remaining 250 parts of the tetrazo solution slowly became too the aniridide suspension added so that at no time a substantial excess of tetrazo compound was present, and where the p n value is obtained by adding 10% nitrous hydroxyl solution was held at 4.0 to 4.5 until all of the coupling component had reacted.

Slurries 1 and 2 were mixed together, and the resulting slurry then boiled for 1 hour heated, and the pigment was then isolated by filtration, the filter cake was washed free of water-soluble impurities and dried at 50.degree.

. Clutch C

A tetrazo solution was made from 25.3 parts of 3,3'-dichlorobenzidine made in 500 parts of water.

17.4 parts of 1-phenyl-3-methyl-5-pyrazolone and 20.7 parts of acetoacet-o-anisidide were dissolved in 500 parts of water containing 8.2 parts of sodium hydroxide. Diluted acetic acid was in given the solution until the p "-VJ was below 7.

The tetrazo solution slowly became the above mixed suspension so added that at no time was a substantial excess of tetrazo compound present, which became the p "value

109853 / 175.1

kept at 4.0 to 4.5 by adding 10% sodium hydroxide solution added until the entire coupling component had implemented. . .

The resulting pigment slurry was allowed to boil for 1 hour heated, and then the pigment was isolated by filtration, the filter cake became free of water-soluble impurities washed and dried at 50.degree.

Coupling D

'Coupling D was done in the same way "as coupling A, however The acetoacet-o-anisidide solution was coupled first, and then this was followed by coupling with the 1-phenyl-3-methyl-5-pyrazolone solution"

The pigment compositions were in print color liquid kit media incorporated, the product of coupling A exhibited superior transparency compared to the product of coupling B, and a "much better transparency, compared to dom Product of coupling C. The pigment composition from coupling Method C could not be compared in terms of color with the others; because their hue was too yellow.

Example 10

i) A tetrazo solution was made from 21.2 parts of o-tolidine (3.3% Di Methylbenzidine) in 500 parts of water.

ii) A tetrazo solution was made from 25.3 parts of 3,3'-dichlorobenzidine made in 500 parts of water.

Hi) A solution was obtained from 37.6 parts of 1-p-tolyl-3-methyl-5-pyr- azolone in 500 parts of water and 11.6 parts of sodium hydroxide manufactured* -

iv) A solution was made of 41.4 parts of acetoacet-o-anisidide in 500 parts of water and 11.6 parts of sodium hydroxide were prepared

109853/1751

Clutch A '-

Dilute acetic acid was added to solution iii) until the p., - value was below 7.0 - the tetrazo solution i) v / became slowly like this admitted that at no time was there a substantial excess of tetrazo compound, the p "value being reduced by addition kept at 4.0 to 4.5 by 10 / b sodium hydroxide solution until all of the coupling component had reacted.

Solution iv) was added to the above coupled slurry, and the ρ -VJert was by suitable addition of 10% sodium Umhydroxydlösung kept below 7.0 »Finally the tetrazo solution ii) was added slowly, and the-.p .-- value -was between 4.0 and 4.5, as described above, adjusted until all of the coupling component had reacted.

The slurry / v urde heated for 1 hour boiling, then the pigment was isolated by filtration, the Filtejrkuchen was washed free of water-soluble impurities, and dried at 50 ⁰ C.

This is an example of the method according to the invention.

Solutions i) and iv) were prepared as described above. '.

Dilute acetic acid was added to solution iii) until the Pjj-VJert fell below 7.0. Tetrazo solution i) was slowly added, the p ^ value, as described above, being 4.0 to 4.5 was held. . ■ '

Dilute acetic acid was added to solution iv) until the powert fell below 7.0. Tetrazole solution ii) was slowly added, the p n value, as described above, being 4.0 to 4.5 was held.

109853/175 1

_ 18 - '

The two coupled slurries were then mixed together combined slurry was heated to boiling for 1 hour, and ■ then the pigment was isolated by filtration. The filter cake was washed free of water-soluble impurities and dried at 50 ° C.

This pigment is classified as a physical mixture,

Clutch C

Solutions i) to iv) were prepared as described above

Dilute acetic acid was added to a mixture of solutions iii) and iv) until the ρ, value was below 7.0. The square solutions i) and ii) were mixed and the combined solution was slowly added, for the p "value as described above. was held at 4.0 to 4.5 *

The slurry was then heated to boiling for 1 hour, and the pigment was then isolated by filtration «The filter cake was washed free of water soluble impurities, and dried at 50 ⁰ C.

This procedure is an example of mixed coupling »

Was the pigment composition obtained from coupling method A in - a book printing ink liquid medium ^ worked, so had this better color vigor, transparency and better gloss compared with a medium in which the product of coupling process B had been incorporated »Both showed the same Hue.

When the pigment composition prepared according to Coupling Method C was incorporated into the same letterpress ink liquid medium, it showed a significantly more yellow hue and could not be compared with the products of Coupling Methods A and B in terms of color. This is due to the presence of asymmetric diarylide compounds- ^ * ':', .. '109853/1751

gen in the final pigment composition, which the Change the shade of the pigment composition.

Example 11

i) A tetrazo solution was made from 21.2 parts of 3,3'-dimethylbenzidine made in 500 parts white.

ii) A tetrazole solution was obtained from 25.3 parts of 3, 3'-dichlorobenzidine made in 500 parts of water.

iii) A solution was made of 75.4 parts of l-p-tolyl-3-methyl-5 ~ pyr-

azolone in 1000 parts of water and 23.2 parts of sodium hydroxide -manufactured.

Clutch A ^

Dilute acetic acid was added to solution iii) until the ρ value fell below 7.0. Tetrazole solution i) was slowly added in such a way that at no time was a substantial excess of tetrazo compound was present, the ρ. value by adding 0 Ο / ό-ig hatriurnhydroxydlösung was kept at 4.0 to 4.5,

Tetrazo solution ii) was slowly added and the p n value became zv / is hen 4.0 and 4.5 held until the entire coupling component had reacted.

The slurry was heated to boiling for 1 hour, and then the pigment was isolated by filtration. The filter cake was washed free of water-soluble impurities and treated with 50 C dried.

This is an example of the inventive method.

Coupling D

A solution iii) was divided into two equal lines a) and b). Dilute acetic acid was added to solution iii a) until the P ₁₁ value fell below 7.0. Tetrazo solution i) was slowly

10 9 8 5 3/1751 »AD

adds, the _e p., ~ value, as described above, was kept at 4.0 to 4.5.

Dilute acetic acid was added to solution iii b) until the p "value fell below 7.0. Tetrazo solution ii) became slow added, the ρ value, as described above, was kept at 4.0 to 4.5.

The two coupled slurries were then mixed together combined slurry was heated to boiling for 1 hour, and • then the pigment was isolated by filtration, the filter cake was washed free of water-soluble impurities and dried at 50.degree.

-This pigment is classified as a physical mixture.

If the pigment Ί.η letterpress ink liquid media is incorporated, the printing inks which contain the pigment composition from coupling process A show superior transparency properties compared to the printing ink which the product according to coupling process B contains. The printing inks have a similar hue.

Example 12 «

I) A tetrazo solution was made from 50.6 parts of 3,3'-dichlorobenzidine made in 1000 parts of water.

ii) A solution was obtained from 37.6 parts of 1-p-tolyl-5-raethylpyrazolone in 500 parts of water and 11.6 parts of sodium hydroxide.

iii) A solution was made from 35.8 parts of 1-phenyl - ^ - methylpyrazolone in 500 parts of water and 11.6 parts of sodium hydroxide.

SAD 109853/1751

Clutch A

Dilute acetic acid was added to solution iii) until the ρ value fell below; 7.0 was. The tetrazo solution i) slowly increased this slurry, as described in Example 9, added, keeping the p "word between 4.5 and 5.0 until the entire coupling component had reacted «,

Solution ii) was slowly added simultaneously with 10% acetic acid added to keep the ρ, value below 7.0. The rest of the solution i) was added slowly, the p "value at 4.5 to "5.0 was held.

The final slurry was heated to boiling for 1 hour. The pigment was isolated by filtration, freed from water-soluble impurities by cleaning and drying at 50.degree.

This is an example of the method according to the invention.

Coupling B

Solutions i) and iii) were prepared as described above. Separate pigment slurries were made as follows manufactured:

Dilute acetic acid was added to solution iii) until the powert was below 7.0. Half of the tetrazo solution i) was added, while the p "~ value between 4.5 and 5.0 by suitable Addition of 10% sodium hydroxide solution was maintained.

Dilute acetic acid was added to solution ii) until the P _H value was below 7.0. The rest of the tetrazo i) was added slowly while maintaining the p _H ~ value between 4.5 and 5.0.

The two slurries were mixed and the one combined Slurry was heated to boiling for 1 hour. The pigment was isolated by filtration, freed from water-soluble impurities by washing and dried at 50.degree. ■ · * "". 109853/1751

This pigment is classified as a physical mixture.

When the pigment is incorporated into a letterpress ink liquid medium, so the pigment composition of the coupling process Λ gives a color with improved tinting power compared to the product of coupling process B. ■.

X-ray powder diffraction studies indicated. That the Pigrnentzusammcnsetzung by coupling method A had a smaller crystallite size than the coupling procedure of & _o

..Example 13

i) A diazo solution was made from 58 parts of m-nitro-p-toluidine in 1500 parts of water were prepared and 55 parts of sodium acetate were added.

: ii) A diazo solution was added to 58.0 parts of p-nitro-o-toluidine made in 1500 parts of water »

iii) A solution was prepared from 57.7 parts of .beta.-Waphthol, 1000 parts and 25 parts VJA sser Natriurahydroxyd made at 60 ⁰ C. 1500 parts of water were added and the solution _s was maintained at 40 C.

iv) A solution was obtained from 110.0 parts of naphthol AS-D

•> NH -T- ^ N

in 'Looo parts of water at 95 ° _C} the Turkish-red 11.7 parts oil and 31 parts of sodium hydroxide contained prepared. By adding what
1500 parts brought.

The volume was increased by adding water at 40.degree

.UAD ORIGINAL 109853/1751

Coupling A

Half of the solution üi) fUglBmai 700 parts of diazo compound i), wherein at no time is there a substantial excess of diazo compound present The remainder of solution iii) was added and the remainder of the diazo solution was then added, again taking care of this te that at no time was there a substantial excess of diazo compound. The slurry was then heated to 40 C, and solution iv) was added. The diazo solution ii) was then added to the combined slurry over 1 hour. which was kept at 40 ° C, added, at no time-a substantial excess of diazo compound was present. The pigment was isolated by filtration, washed to remove water-soluble impurities and dried at 50 ° C.

Coupling B

The two pigments were prepared in separate vessels using the same amounts and conditions as noted above. After coupling, the two slurries were mixed and held at 40 ° C for 1 hour. The physical mixture of the slurries was then filtered, the filter cake was washed to remove water-soluble impurities, and the pigment was dried at 50 ⁰ C.

The obtained products were put into a letterpress color liquid medium incorporated, the pigment composition prepared by Coupling Method A showed a stronger one Tinting power and better transparency than that made according to coupling method B.

Example 14

Example 3 was repeated, but the naphthol AS-F was through Naphthol AS-E

109853/1751

(113.6 parts) and the p-nitro-o-toluidine by m-nitro-o-toluidine (58 parts) replaced. The pigment composition produced according to the invention had better coloring power and transparency properties as a simple mixture of the pigments when incorporated into letterpress color liquid media.

•AWAY

10 9 8 5 3/1751

Claims (12)

Sponsorship claims 1.) Pigment composition, characterized in that it fine particles of a first organic pigment wholly or at least partially with a second organic pigment Pigment coated contains. 2.) pigment composition according to claim 1, characterized in that either one or both pigments are an azo pigment «, 3.) pigment composition according to claim 2, characterized in that that either or both of the pigments are an "arylamide or a dicirylamide pigment." 4.) Process for the preparation of a pigment composition according to claim 1, characterized in that a slurry from a first organic pigment and that then a second organic pigment in the slurry is precipitated. 5.) Method according to claim 4, characterized in that either or both of the pigments are azo pigment. 6.) The method according to claim 5, characterized in that % of either one or both of the pigments is an acetoacetarylide pigment. 7.) Method according to claim 5, characterized in that either or both of the pigments are an azo pigment obtained by coupling 1 mole of a tetrazotized diaminodiphenyl obtained with 2 moles of an acetoacetic anilide. 8.) Method according to claim 7, characterized in that
either or both of the pigments are a pyrazolone pigment. 109853/175 1 .- 26 - 9. *) Method according to claim 8, characterized in that either or both of the pigments are azo pigment, obtained by coupling 1 mole of tetrazotized diaminodiphenyl with 2 moles of phenyl-3-iri.ethyl-pyrazolone-5. 10.) The method according to claim 9, characterized in that either one or both of the pigments is a naphthol pigment are. 11.) The method according to claim 10, characterized in that d.aß _Either one or both of the pigments is an azo-pigment. are, that you can do by coupling a diazotized aminobenzene with 2,3-Hydroxynaphthoic acid arylide receives «. 12.) Method according to one of claims 4 to 11, characterized in that that the first organic pigment or the second organic pigment is treated with an organic Solvent, surfactant or resin may be subjected before coating he follows. ßAD ORIGINAL 109853/175 1