Pigment preparations

Pigment preparation essentially comprising PA0 a) at least one pigment from the class of azo, anthrapyrimidine, anthanthrone, quinacridone, perinone, diketopyrrolopyrrole, dioxazine, flavanthrone, indanthrone, isoindolinone, isoviolanthrone, perylene, phthalocyanine, pyranthrone or thioindigo pigments or a mixture of pigments belonging to various classes, and PA0 b) at least one dispersant of the formula (I) ##STR1## in which P, independently of the pigments mentioned in a), is a radical of an anthanthrone azo, quinacridone, perinone, diketopyrrolopyrrole, dioxazine, indanthrone, perylene, phthalocyanine or thioindigo pigment, PA1 R.sup.1 and R.sup.2, independently of one another, are hydrogen, halogen, C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxy or nitro, and PA1 n is a number from 1 to 4, and their use for pigmenting of high-molecular-weight materials in the form of plastic compositions, melts, spinning solutions, varnishes, in particular of polyurethane-based aqueous varnishes or low-solvent high-solid acrylic varnishes, coating compositions and printing inks, in particular based on nitrocellulose.

The present invention is in the technical field of pigment preparations and 
their use for the pigmenting of high-molecular-weight materials. 
The dispersion of pigments in high-molecular-weight materials can result in 
a large number of problems, in particular if the pigments are to be 
dispersed not only in customary but also in novel low-solvent high-solid 
and highly polar aqueous coating systems. For instance, dispersion in some 
coating systems may remain incomplete, and the optimum color strength is 
not obtained. Incompletely dispersed agglomerates and large particles may 
interfere with further processing and, in particular, may result in 
sedimentation problems in the case of systems of low viscosity (lacquers 
and printing inks). Furthermore, flocculations in dispersion, storage or 
further processing can lead to unwanted rheological modifications of the 
system and to surface defects, and to losses in color strength and luster 
of the applied film. 
These problems cannot be solved by the known pigment concentrates. In 
particular, dispersion in the above-mentioned novel coating systems leads 
to considerable problems. 
U.S. Pat. No. 4,310,359 describes pigment concentrates which have improved 
flocculating stability and favorable rheological properties in coating 
systems. In aqueous coating systems, the pigment concentrates described in 
this publication lead in several cases to unsatisfactory results, and the 
process cannot be applied to certain classes of pigments. In addition, the 
compounds mentioned there have different structures. 
U.S. Pat. No. 4,256,507 describes pigment concentrates based on pigment 
dispersants containing phthalimidomethylene groups. These pigment 
concentrates do not fulfil the requirements in many cases with respect to 
coloristic and rheological properties demanded of pigment concentrates. 
The compounds mentioned there also have different structures. 
British Patent No. 1,367,635 describes quinophthalone dyes containing 
ortho-sulfobenzimidomethylene groups, which are used for the dyeing of 
fibers. Owing to their high solubility, these compounds are not suitable 
for use in the pigment sector. 
The object of the present invention is to provide new dispersants for 
organic pigments and pigment preparations which can be prepared therefrom 
in a simple manner and have improved coloristic and rheological properties 
in high-molecular-weight materials. It has now been found that pigment 
preparations having excellent coloristic and rheological properties in 
customary as well as modern binder systems of the high-solid or 
water-based type can be obtained by surface modification of organic 
pigments using new dispersants preparable by reaction of 
hydroxymethylsaccharin or derivatives thereof with the organic pigment. 
The present invention relates to pigment preparations consisting 
essentially of 
a) at least one organic pigment from the class of azo, anthrapyrimidine, 
anthanthrone, quinacridone, perinone, diketopyrrolopyrrole, dioxazine, 
flavanthrone, indanthrone, isoindolinone, isoviolanthrone, perylene, 
phthalocyanine, pyranthrone or thioindigo pigments or a mixture of 
pigments belonging to various of the abovementioned classes, and 
b) at least one dispersant of the formula (I) 
##STR2## 
in which P, independently of the pigments mentioned in a), is a radical 
of an azo, anthanthrone, quinacridone, perinone, diketopyrrolopyrrole, 
dioxazine, indanthrone, perylene, phthalocyanine or thioindigo pigment, 
R.sup.1 and R.sup.2, independently of one another, are hydrogen, halogen, 
C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxy or nitro, preferably 
hydrogen, and 
n is a number from 1 to 4, preferably from 1 to 3.6, 
and in which the CH.sub.2 group of the saccharin radical is bound to an 
aromatic carbon atom of P. 
In each case, "radical" is understood to mean the parent compound minus at 
least one hydrogen atom. 
The abovementioned classes of organic pigments are known from the 
literature, for example from W. Herbst, K. Hunger, Industrielle Organische 
Pigmente (Industrial Organic Pigments) (1987), VCH Verlagsgesellschaft, 
Weinheim, Germany. Diketopyrrolopyrrole pigments are described in U.S. 
Pat. No. 4,579,949. 
The number n expresses the degree of substitution obtained by condensation 
of the pigment compound on which the radical P is based. The optimum value 
for n depends on the chemical constitution, the crystalline and surface 
properties of the pigment and the properties of the application medium and 
must be determined experimentally in the individual case for each 
pigment/application medium combination. If the values of n are too low or 
too high, optimum pigment properties are not achieved. Usually, the 
dispersant is a mixture of compounds of the formula I in which on average 
n parts of the saccharin radical are bound to one part of the pigment 
radical P. Therefore, n can also adopt fractional numerical values. 
Preferred pigment preparations are those comprising at least one pigment 
from the class of indanthrone, perylene, quinacridone, phthalocyanine or 
perinone pigments. 
Preferred pigment preparations are furthermore those comprising at least 
one dispersant of the formula (I) in which, independently of the pigments 
used, P is a radical of an indanthrone, perylene, quinacridone, 
phthalocyanine or perinone pigment. 
Preferred pigment preparations are furthermore those which consist 
essentially only one of the pigments mentioned and one of the dispersants 
mentioned. 
Particular preference is given to pigment preparations consisting 
essentially 
a) 99.5 to 70% by weight, preferably 95 to 80% by weight, of at least one 
of the abovementioned pigments; 
b) 0.5 to 30% by weight, preferably 5 to 20% by weight, of at least one of 
the abovementioned dispersants; 
c) 0 to 10% by weight, preferably 0 to 5% by weight, of one or more 
surfactants; and 
d) 0 to 10% by weight, preferably 0 to 5% by weight, of customary 
additives, the proportions of the components being based in each case on 
the total weight (100% by weight) of the pigment concentrate. 
The present invention furthermore relates to dispersants of the formula (I) 
##STR3## 
in which P is a radical of an azo, anthanthrone, quinacridone, perinone, 
diketopyrrolopyrrole, dioxazine, indanthrone, perylene, phthalocyanine or 
thioindigo pigment, 
R.sup.1 and R.sup.2, independently of one another, are hydrogen, halogen, 
C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxy or nitro, preferably 
hydrogen, and 
n is a number from 1 to 4, preferably from 1 to 3.6, 
and in which the CH.sub.2 group of the saccharin radical is bound to an 
aromatic carbon atom of P. 
The dispersants of the formula I can be prepared by customary processes by 
condensation of pigments with the corresponding saccharin derivative and 
formaldehyde, paraformaldehyde, another formaldehyde-releasing compound, 
for example trioxane, or the corresponding N-methylol derivative of 
saccharin in the presence of condensating agents at a temperature of 
between 0.degree. C. and 150.degree. C. Preferred condensating agents are 
80 to 100% by weight sulfuric acid, oleum or polyphosphoric acid. The 
condensation product is precipitated by introducing the sulfuric or 
phosphoric acid solution into water or ice/water and isolated in the usual 
manner by filtration and washing until neutral. The degree of substitution 
can be determined by elemental analysis and NMR spectra. 
When concentrated sulfuric acid or oleum is used as the condensating 
medium, it is possible for sulfo groups to be incorporated to a small 
extent in the compounds according to the invention. 
The degree of substitution n of pigment P can be achieved directly. 
However, it is also possible to prepare a derivative of the formula I and 
adjust it to the final degree of substitution n in a further step. This 
adjustment of the degree of substitution n can take place in a subsequent 
process step (fine dispersion, finishing, wet or dry milling, final 
mixture). 
When the pigment preparations are prepared, the dispersants can be added 
during the pigment synthesis, during the fine dispersion process, before 
or after a finishing process. The fine dispersion can be carried out in a 
mechanical process, for example wet or dry milling, or a chemical process, 
for example dissolution in strong acids or bases and precipitation or 
vatting and subsequent reoxidation. The pigment preparations can also be 
prepared by mixing the dispersants with the pigments 
The pigments contained in the pigment preparations according to the 
invention can be present as pure pigments, as mixtures of at least two 
pigments or as mixed crystals of at least two pigments. 
The dispersant content in the pigment preparations is advantageously 
between 0.5 and 30% by weight, preferably 1 and 15% by weight, relative to 
the weight of the pigment. The improvement in the coloristic and 
rheological properties by virtue of addition of the dispersant increases 
with increasing amount, but only to a specified optimum concentration 
which depends on the chemical constitution, the crystalline and surface 
properties of the pigments, of the dispersant, and on the properties of 
the application medium and can be determined experimentally in the 
individual case for each pigment/dispersant/application medium 
combination. 
Higher concentrations, in turn, lead to a deterioration of the properties. 
In the pigment preparations, the dispersants of the formula (I) can be 
derived from the pigment present in the preparation or from a different 
compound of the abovementioned classes of pigment. In any case, the 
addition of the dispersant results in an improvement in the coloristic and 
rheological properties. 
However, the dispersants can lead to a shift in hue, in particular when 
they are derived from pigments which differ from the pigment of the 
pigment preparation, so that in a preferred embodiment the pigments 
mentioned above in a) and b) belong in each case to the same class. 
The pigment preparations of the invention can additionally contain 
surfactants and further customary additives, such as resins, rheological 
additives, preservatives and/or dustproofing agents, such as described, 
for example, in K. Lindner, Tenside-Textilhilfsmittel-Waschrohstoffe, 
Volume 1, pages 837-917 (1964) or in N. Schonfeld, Grenzflachenaktive 
Ethylenoxid-Addukte, pages 42-95 (1976). 
The pigment preparations according to the invention are distinguished by 
their excellent coloristic and rheological properties, in particular 
flocculating stability, dispersibility, rheology, luster and color 
strength. 
The pigment preparations according to the invention are suitable in 
particular for the pigmenting of high-molecular-weight organic materials, 
for example cellulose ethers and cellulose esters, such as ethylcellulose, 
nitrocellulose, cellulose acetate, cellulose butyrate, natural resins or 
synthetic resins, such as polymerization resins or condensation resins, 
for example amino resins, in particular urea/- and melamine/formaldehyde 
resins, alkyd resins, acrylic resins, phenolic resins, polycarbonates, 
polyethylene, polypropylene, polyacrylonitrile, polyacrylic esters, 
polyamides, polyurethanes or polyesters, rubber, casein, silicone and 
silicone resins, either individually or in mixtures with one another. 
It is immaterial whether the high-molecular-weight organic compounds 
mentioned are present in the form of plastic compositions, melts or in the 
form of spinning solutions, varnishes, coating compositions or printing 
inks. Depending on the particular application, it may prove advantageous 
to use the pigment preparations according to the invention as toners or in 
the form of preparations or dispersions. The pigment preparations are used 
in an amount of preferably 0.1 to 10% by weight, relative to the 
high-molecular-weight organic material to be pigmented. Particularly 
preferred coating systems are the new type of highly polar aqueous 
polyurethane-based varnishes and the low-solvent high-solids acrylic resin 
varnishes of high solids content. Customary coating systems from the class 
of alkyd/melamine resin varnishes and two-component varnishes based on 
acrylic resins crosslinkable with polyisocyanate are also suitable. Of the 
large number of printing inks, those based on nitrocellulose are 
particularly suitable. 
The pigment preparations according to the invention and the dispersants 
according to the invention are easily dispersible in many application 
media to a very fine state of division. These dispersions have high 
flocculating stability and exhibit excellent rheological properties, even 
with a high degree of pigmenting. They can be used to prepare coatings and 
prints of high color strength, high gloss and high transparency, which 
have excellent fastness properties. From the large number of known 
systems, an alkyd/melamine resin varnish (AM) based on a medium-oil, 
non-drying alkyd resin comprising synthetic fatty acids and phthalic 
anhydride and a melamine resin etherified with butanol and portions of a 
non-drying alkyd resin based on ricinenic acid (short-oil), a high-solid 
acrylic baking enamel based on a non-aqueous dispersion (TSA) and a 
polyurethane-based (PUR) aqueous varnish were selected for rating the 
properties. 
The rheology of the mill base after dispersion is rated by the following 
five-step scale: 
______________________________________ 
5 highly fluid 
2 slightly solidified 
4 fluid 1 solidified 
3 viscous 
______________________________________ 
After diluting the mill base to the pigment concentration, the viscosity is 
rated using a Rossmann visco-spatula, for example of the 301 type from 
Erichsen, Iserlohn. Before coating, the desired viscosity was adjusted in 
such a manner that it corresponded to a specific flow time in the Ford cup 
(nozzle diameter 4 mm) given in seconds (s). Gloss measurements were 
carried out using a multigloss gloss tester, for example from 
Byk-Mallinckrodt, Wesel, at an angle of 20.degree. according to DIN 67530 
(ASTM D 523). In the examples which follow, parts and percentages are by 
weight. 
6 and 3% oleum is understood to mean a solution of 94 and 97% by weight of 
100% sulfuric acid and 6 and 3% by weight of dissolved SO.sub.3. 
The degree of substitution n was determined in all examples not only by 
elemental analysis but also by .sup.1 H NMR spectra, the basis for the 
determination being the ratio of the aliphatic to the aromatic protons.

EXAMPLE 1 
##STR4## 
300 g of 6% oleum were initially introduced into a stirred vessel, and 20.9 
g (0.05 mol) of N,N'-dimethylperylenetetracarboximide were then introduced 
at a temperature of 25.degree. C. and dissolved. 42.6 g (0.2 mol) of 
hydroxymethylsaccharin were then added, the mixture was heated to 
100.degree. C. and stirred at this temperature for another 4 hours. The 
solution was allowed to cool to 25.degree. C., poured into 2000 g of ice 
water, the product was filtered off with suction and washed until neutral. 
The filter residue was stirred with 250 ml of water, brought to a pH of 9 
with 2.25 g of 33% sodium hydroxide solution, stirred for another hour, 
filtered off with suction, washed until neutral and dried, giving 40.85 g 
of the dispersant of the formula II. 
Analysis: Calculated: C, 62.4%; H, 3.0%; N, 6.9%; S, 7.9%. Found: C, 61.2%; 
H, 2.9%; N, 6.7%; S, 8.0%. .sup.1 H NMR spectrum in D.sub.2 SO.sub.4 (in 
ppm): .delta. 7.5-9.3: 14 aromatic H; 4.5-6.0: 2 aliphatic CH.sub.2 ; 3.5 
-3.9: 2 CH.sub.3. 
EXAMPLE 1a 
15 g of C.I. Pigment Red 179, prepared according to U.S. Pat. No. 5,110,931 
were mechanically mixed with 0.15 g of the dispersant of the formula (II), 
and the pigment preparation was incorporated in AM varnish and PUR varnish 
and tested. The AM varnish gave a coating of high hiding power and color 
strength. The rheology was given a rate of 5, and the gloss was 81. 
Without dispersant, the coating had a much lower color strength, the 
rheology was given a rating of 1 to 2, and the gloss was 35. 
This was repeated, except that the dispersant of the formula (II) was 
replaced by a dispersant based on N,N'-dimethylperylenecarboximide and 
hydroxymethyl phthalimide having a degree of substitution n of 2.6 and 
prepared according to U.S. Pat. No. 4,256,507 Example A, experiment B, 
giving a coating which had a much lower color strength than that obtained 
with a dispersant of the formula II. The rheology was given a rating of 5, 
and the gloss was 78. 
The PUR varnish in which the pigment preparation described at the beginning 
of this example was incorporated gave a coating of high hiding power and 
color strength. The rheology was given a rating of 5 and the viscosity was 
3.0 s. Without dispersant, the coating had a somewhat lower color 
strength. The rheology was given a rating of 5, and the viscosity was 3.5 
s. 
This was repeated, except that the dispersant of the formula (II) was 
replaced by a dispersant based on N,N'-dimethylperylenetetracarboximide 
and hydroxymethyl phthalimide, giving a coating of significantly lower 
color strength. The rheology was given a rating of 5, and the viscosity 
was 2.2 s. 
EXAMPLE 2 
##STR5## 
300 g of 6% oleum were initially introduced into a stirred vessel, and 20.9 
g (0.05 mol) of N,N'-dimethylperylenetetracarboximide were then introduced 
at a temperature of 25.degree. C. and dissolved. A mixture of 6 g of 
paraformaldehyde (corresponding to 0.2 mol of formaldehyde) and 36.6 g 
(0.2 mol) of saccharin were then added, the mixture was heated to 
100.degree. C. and stirred at this temperature for another 4 hours. The 
solution was allowed to cool to 25.degree. C., poured into 2000 g of ice 
water, the product was filtered off with suction and washed until neutral. 
The filter residue was stirred with 250 ml of water, brought to a pH of 9 
with 2.25 g of 33% sodium hydroxide solution, stirred for another hour, 
filtered off with suction, washed until neutral and dried, giving 25.8 g 
of the dispersant of the formula (III) still containing about 50% of 
unsubstituted N,N'-dimethylperylenetetracarboximide. 
Analysis: (calculated for the 1:1 mixture of (III) and unsubstituted 
starting material): Calculated: C, 69.8%; H, 3.2%; N, 6.8%; S, 3.1% . 
Found: C, 68.4%; H, 2.9%; N, 6.6%; S, 2.9%. .sup.1 H NMR spectrum in 
D.sub.2 SO.sub.4 (in ppm): .delta. 7.6-9.3: 19 aromatic H; 4.5-5.8: 1 
aliphatic CH.sub.2. 
EXAMPLE 2a 
15 g of C.I. Pigment Red 179, prepared according to U.S. Pat. No. 5,110,931 
were mechanically mixed with 0.15 g of the dispersant of the formula 
(III), and the pigment preparation was incorporated in AM varnish and 
tested. A coating of high hiding power and color strength was obtained. 
The rheology was given a rating of 4 to 5, the viscosity was 3.53 s and 
the gloss 74. 
Without dispersant, the coating had lower color strength, the rheology was 
given a rating of 1 to 2, the viscosity was 4.3 s and the gloss 35. 
EXAMPLE 3 
##STR6## 
300 g of 6% oleum were initially introduced into a stirred vessel, and 19.6 
g (0.5 mol) of perylenetetracarboxylic dianhydride were then introduced at 
a temperature of 25.degree. C. and dissolved. 42.6 g (0.2 mol) of 
hydroxymethylsaccharin were then added, the mixture was heated to 
100.degree. C. and stirred at this temperature for another 4 hours. The 
solution was allowed to cool to 25.degree. C., poured into 2000 g of ice 
water, the product was filtered off with suction, washed until neutral and 
dried, giving 37.4 g of the dispersant of the formula (IV). 
Analysis: Calculated: C, 62.0%,; H, 2.3%; N, 3.4%; S, 7.8%. Found: C, 60.9% 
H, 2.6%; N;3.4%; S 7.2%. .sup.1 H NMR spectra in D.sub.2 SO.sub.4 (in 
ppm): .delta. 7.6-9.2: about 13 aromatic H; 5.0-6.1: about 1.8 aliphatic 
CH.sub.2. 
EXAMPLE 3a 
1050 ml of deionized water were initially introduced into a stirred vessel, 
and 50 g of perylenetetracarboxylic dianhydride, prepared according to 
U.S. Pat. No. 4,650,879 and 0.5 g of the dispersant of the formula (IV), 
both in the form of a moist press cake, were then introduced with 
stirring. The mixture was cooled to a temperature of 0.degree. to 
5.degree. C., and 104 g of 40% monomethylamine solution were added 
dropwise at this temperature, and stirring at 0.degree. to 5.degree. C. 
was continued for 15 minutes. A solution of 28.5 g of anhydrous calcium 
chloride and 94.5 ml of water were then added dropwise at 0.degree. to 
5.degree. C. over a period of 15 minutes, and stirring at this temperature 
was continued for 1 hour. The mixture was then heated to 80.degree. C. and 
stirred at about 80.degree. C. for another hour. A suspension of 2.7 g of 
distearyldimethylammonium chloride and 117 ml of water were then added 
dropwise, and the mixture was stirred at 80.degree. C. for another hour. 
It was cooled to 50.degree. C., brought to a pH of 7 to 7.5 by dropwise 
addition of 98% formic acid, stirred at 50.degree. C. for another 30 
minutes, filtered off with suction, and the product was washed with water 
until free from chloride and dried. 
This gave 54.2 g of a pigment preparation based on Pigment Red 179, which, 
upon incorporation in TSA varnish produced transparent coatings of high 
color strength. After the reaction, the dispersant had the formula II, 
except that n was the number 1.8. 
EXAMPLE 4 
##STR7## 
400 g of 96% sulfuric acid were initially introduced into a stirred vessel, 
and 28.7 g (0.05 mol) of copper phthalocyanine were then introduced at a 
temperature of 25.degree. C. and dissolved. 42.6 g (0.2 mol) of 
hydroxymethylsaccharin were then added, the mixture was heated to 
50.degree. to 55.degree. C. and stirred at this temperature for another 5 
hours. The solution was allowed to cool to 25.degree. C., poured into 2000 
g of ice water, the product was filtered off with suction and washed until 
neutral. The filter residue was stirred with 1000 ml of water, brought to 
a pH of 11 with 1.24 g of 33% sodium hydroxide solution, stirred for 
another hour, filtered off with suction, washed until neutral and dried, 
giving 57.0 g of the dispersant of the formula (V). 
Analysis: Calculated: C, 58.1%; H, 12.7%; N, 13.4%; S, 8.1%. Found: C, 
58.1%; H 3.3%; N, 13.9%; S 7.2% . 
EXAMPLE 4a 
A 1 liter porcelain vessel was filled with 35 g of copper phthalocyanine 
crude pigment of .beta.-phase, 10.6 g of dispersant of the formula (V), 
165 ml of water and 1200 g of quartz beads of diameter 2 mm, and the 
mixture was then milled in a vibrating mill for 15 hours. The quartzite 
beads were then removed from the mill base by screening, and the mill base 
was filtered off with suction and dried, giving 36.4 g of pigment 
preparation which, on incorporation in AM, TSA and PUR varnish produced 
coatings of high color strength. Without a dispersant, the coatings had a 
much lower color strength. The rheology and viscosities of the coatings 
with and without dispersant were the same. 
EXAMPLE 4b 
75 g of 85% isobutanol, 50 g of finely divided mill base composed of C.I. 
Pigment Violet 23 (containing 22% of salt from the synthesis), prepared 
according to U.S. Pat. No. 4,253,839 2.5 g of the dispersant of the 
formula (V) as press cake and 2.5 g of 98% formic acid were introduced in 
succession into a stirred vessel, and the mixture was stirred at 
25.degree. C. for 22 hours. During this time, another 100 g of 85% 
isobutanol were added drop-wise. 300 ml of water were then added, and the 
mixture was heated to boiling for 5 hours. The isobutanol was then 
distilled off, and the residue filtered off with suction, washed until 
neutral and dried. 
This gave 40.4 g of pigment preparation which, upon incorporation in 
polyvinyl chloride, produced transparent colorations of high color 
strength. 
EXAMPLE 5 
##STR8## 
100 g of 3% oleum were initially introduced into a stirred vessel, and 10 g 
(0.02 mol) of indanthrone were then introduced at a temperature of 
25.degree. C. and dissolved. 19.3 g (0.09 mol) of hydroxymethylsaccharin 
were then added, the mixture was heated to 60.degree. C. and stirred at 
this temperature for another 4 hours. The solution was allowed to cool to 
25.degree. C., poured into 500 g of ice water, the product was filtered 
off with suction and washed until neutral. The filter residue was stirred 
with 250 ml of water, brought to a pH of 9 with 2.0 g of 33% sodium 
hydroxide solution, stirred for another hour, filtered off with suction, 
washed until neutral and dried, giving 20.6 g of the dispersant of the 
formula (VI). 
Analysis: Calculated: C, 62.6%; H, 2.9%; N, 7.1% ; S, 8.1%. Found: C, 
61.0%; H, 2.9%; N, 6.2%; S, 8.6%. 
.sup.1 H NMR spectrum in D.sub.2 SO.sub.4 (in ppm): .delta. 7.5-9.0: about 
18 aromatic H; 5.0: about 2 CH.sub.2. 
This was repeated, using the same molar amount of 
4-chlorohydroxymethylsaccharin instead hydroxymethylsaccharin, giving a 
dispersant having similar properties. 
EXAMPLE 5a 
3200 g of steel balls of diameter 10 mm were introduced into a 1.4 liter 
rolling mill, 27 g of crude indanthrone pigment recrystallized from 
sulfuric acid and 3 g of the dispersant of the formula (VI) were added, 
and the mixture was then rolled for 24 hours. The rotating speed was 70% 
of the critical rotating speed. The mill base was then separated off from 
the grinding medium by screening, introduced into 40 g of 85% isobutanol, 
and the mixture was stirred at 25.degree. C. for 24 hours. 150 ml of water 
and 5 g of 98% formic acid were added, the mixture was heated to boiling 
for 5 hours, and the isobutanol was distilled off. The product was then 
filtered off with suction, washed with water until neutral and dried, 
giving a pigment preparation which, upon incorporation in TSA varnish 
produced transparent coatings of high color strength. 
EXAMPLE 6 
##STR9## 
150 g of 100% sulfuric acid were initially introduced into a stirred 
vessel, and 7.2 g (0.03 mol) of diketopyrrolopyrrole were then introduced 
at a temperature of 25.degree. C. and dissolved. 21.3 g (0.1 mol) of 
hydroxmethylsaccharin were then added, the mixture was heated to 
50.degree. C. and stirred at this temperature for another 5 hours. The 
solution was allowed to cool to 25.degree. C., poured into 1500 g of ice 
water, the product was filtered off with suction, washed until neutral and 
dried. This gave 22.6 g of the dispersant of the formula (VII). 
Analysis: Calculated: C, 57.4%; H, 3.1%; N, 8.0%; S, 11.2%. Found: C, 
55.9%; H, 3.2%; N, 8.1%; S, 10.9%. 
.sup.1 H NMR spectrum in D.sub.2 SO.sub.4 (in ppm): .delta. 7.0-8.6: about 
19 aromatic H; 4.6-6.2: about 3 CH.sub.2. 
This was repeated, using the same molar amount of 
4-methoxy-7-nitrohydroxymethylsaccharin instead of hydroxymethylsaccharin, 
giving a dispersant having similar properties. 
EXAMPLE 6a 
9.75 g of C.I. Pigment Red 254 were mechanically mixed with 0.25 g of the 
dispersant of the formula (VII), and the pigment preparation was 
incorporated in AM varnish and tested. A coating of high color strength 
was obtained. The rheology was given a rating of 5, and the gloss was 75. 
EXAMPLE 7 
##STR10## 
250 g of 100% sulfuric acid were initially introduced into a stirred 
vessel, and 20.6 g (0.05 mol) of C.I. Pigment Orange 43 were then 
introduced at a temperature of 25.degree. C. and dissolved. 42.6 g (0.2 
mol) of hydroxymethylsaccharin were then added, the mixture was heated to 
105.degree. C. and stirred at this temperature for another 4 hours. The 
solution was allowed to cool to 25.degree. C., poured into 2000 g of ice 
water, the product was filtered off with suction and washed until neutral. 
The filter residue was stirred with 250 ml of water, brought to a pH of 
13.6 with 7.5 g of 33% sodium hydroxide solution, stirred for another 
hour, filtered off with suction, washed until neutral and dried, giving 
35.6 g of the dispersant of the formula (VIII). 
Analysis: Calculated: C, 64.7%; H, 2.8%; N, 10.9%; S, 6.8%. Found: C, 
63.3%; H, 2.9%; N, 11.1%; S, 6.9%. 
.sup.1 H NMR spectrum in D.sub.2 SO.sub.4 (in ppm): .delta. 7.5-9.2: about 
16.5 aromatic H; 5.0-5.4: 3 aliphatic H. 
This was repeated, using the same molar amount of 
5-methylhydroxymethylsaccharin instead of hydroxymethylsaccharin, giving a 
dispersant having similar properties. 
EXAMPLE 7a 
9.5 g of C.I. Pigment Orange 43 were mechanically mixed with 0.5 g of the 
dispersant of the formula (VIII), and the pigment preparation was 
incorporated in AM varnish and PUR varnish and tested. The AM varnish gave 
a transparent coating of high color strength and excellent cross-coating 
fastness. The rheology was given a rating of 5, and the gloss was 83. 
Without a dispersant, the coating had considerably more hiding power, was 
brighter and had a lower color strength. The rheology was given a rating 
of 1, and the gloss was 25. The PUR varnish gave a transparent coating of 
high color strength. The rheology was given a rating of 5, and the gloss 
was 80. Without dispersant, the coating had considerably more hiding 
power, was brighter and had a lower color strength. The rheology was given 
a rating of 1 to 2, and the gloss was 42. 
This was repeated, except that the dispersant of the formula (VIII) was 
replaced by a dispersant based on C.I. Pigment Orange 43, 
hydroxymethylhalofatty amides and amines containing basic groups and 
prepared according to US Patent No. 3,973,981 (Example 1, Preparation 5), 
giving, upon incorporation in AM varnish, a coating which is much darker 
and more opaque than that obtained with the dispersant of the formula 
(VIII). The rheology was given a rating of 4 to 5, and the gloss was 46. 
EXAMPLE 7b 
76 g of a crude 4,10-dibromoanthanthrone pigment in the form of a moist 
press cake were stirred with 130 ml of water. 4 g of the dispersant of the 
formula (VIII) and 5 g of 98% formic acid were added to the suspension, 
and the mixture was stirred for another 15 minutes. This suspension was 
then poured into a pearl mill which had been filled with 1160 g of 
quartzite beads of diameter 1 mm, and the mixture was milled at a rotating 
speed of 2800 revolutions per minute for 2 hours. The mill base was then 
removed by screening, and the quartzite beads were rinsed with water. The 
suspension was filtered off with suction and washed with water. The filter 
cake was then stirred with such an amount of water that the weight of the 
suspension was 960 g. 240 g of 100% n-butanol were then added, and the 
mixture was heated to boiling for 3 hours. The n-butanol was then 
distilled off, the product was filtered off with suction at 50.degree. C., 
washed with water and dried at 80.degree. C., giving 79.3 g of pigment 
preparation. After incorporation in AM varnish and testing, coatings of 
high color strength were obtained. The rheology was given a rating of 4 to 
5 and the gloss was 70. 
If the dispersant was omitted in the preparation of the pigment 
preparation, a coating of significantly lower color strength was obtained. 
The rheology was given a rating of 1 and the gloss was 64. 
EXAMPLE 8 
##STR11## 
350 g of polyphosphoric acid (82 to 84% of P.sub.2 O.sub.5) were initially 
introduced into a stirred vessel and heated to 5.degree. C. 17.4 g (0.05 
mol) of 2,5-dianilinoterephthalic acid were introduced at that temperature 
over 1 hour. 
Stirring at 125.degree. C. was continued for 1 hour. The mixture was then 
cooled to 80.degree. C., and 42.6 g (0.2 mol) of hydroxymethylsaccharin 
were introduced at this temperature over a period of 30 minutes. The 
mixture was then heated to 120.degree. C. and stirred at this temperature 
for another 4 hours. After reaction was complete, the solution was poured 
into 2000 g of ice water, stirring was continued for 1 hour, the product 
was filtered off with suction, washed until neutral and dried, giving 50.7 
g of the dispersant of the formula (IX). 
Analysis: Calculated: C, 57.6%; H, 3.0%; N, 7.7%; S, 11.3% . Found: C, 
56.8%; H, 3.0%; N, 7.5%; S, 10.2%. 
.sup.1 H NMR spectrum in D.sub.2 SO.sub.4 (in ppm): .delta. 7.4-9.6: about 
20 aromatic H; 4.9-5.8: about 7 aliphatic H. 
This is repeated, using the same molar amount of 
4,7-dichlorohydroxymethylsaccharin instead of hydroxymethylsaccharin, 
giving a dispersant having similar properties. 
EXAMPLE 8a 
44 g of a crude 2,9-dimethylquinacridone pigment in the form of a moist 
press cake were stirred with 270 g of 100% isobutanol. 4.4 g of the 
dispersant of the formula (IX) were introduced into this suspension in the 
form of a moist press cake, and 6.6 g of 33% sodium hydroxide solution 
were added dropwise. The mixture was then heated in an autoclave to 
125.degree. C. and stirred at this temperature for 3 hours. It was then 
cooled to 90.degree. C., and the isobutanol was distilled off. After 
cooling to 50.degree. C., the pigment preparation was filtered off with 
suction at this temperature, washed with water until neutral and dried at 
80.degree. C., giving 46.2 g of pigment preparation. After incorporation 
in PUR varnish and testing, a transparent coating of high color strength 
was obtained. The rheology was given a rating of 4. 
Without dispersant, the coating was more hiding and a had a lower color 
strength. The rheology was given a rating of 4. 
This was repeated, except that the dispersant of the formula IX was 
replaced by a dispersant based on quinacridone sulfonamides, prepared 
according to U.S. Pat. No. 4,310,359 Preparation Example 1, giving 
coatings of much lower color strength. Upon incorporation in AM varnish, a 
coating of high color strength was obtained. Without dispersant, the 
coating had a somewhat lower color strength. 
EXAMPLE 9 
##STR12## 
150 g of polyphosphoric acid (82 to 84% of P.sub.2 O.sub.5) were initially 
introduced into a stirred vessel, and 5.7 g (0.01 mol) of C.I. Pigment Red 
170 were then introduced at 80.degree. C. and dissolved. 10.7 g (0.05 mol) 
of hydroxymethylsaccharin were then added, the mixture was heated to 
95.degree. C. to 100.degree. C. and stirred at this temperature for 4 
hours. The solution was poured into 1000 g of ice water, the product was 
filtered off with suction, washed until neutral and dried at 80.degree. 
C., giving 12.8 g of the dispersant of the formula (X). 
Analysis: Calculated: C, 57.9%; H, 3.6%; N, 9.5%; S, 9.7%. Found: C, 56.7%; 
H, 3.6%; N, 8.3%; S, 9.0%. 
.sup.1 H NMR spectrum in D.sub.2 SO.sub.4 (in ppm): .delta. 7.4-9.2: about 
22 aromatic H; 4.7-6.0: about 6 H. 
EXAMPLE 9a 
9.5 g of C.I. Pigment Red 170 were mechanically mixed with 0.5 g of the 
dispersant of the formula (X), and the pigment preparation was 
incorporated in AM varnish and tested. A coating of high color strength 
was obtained. The rheology was given a rating of 4, and the gloss was 77. 
Without dispersant, the coating was brighter, the rheology was given a 
rating of 2, and the gloss was 75. 
EXAMPLE 10 
##STR13## 
1200 g of polyphosphoric acid (82 to 84% of P.sub.2 O.sub.5) were initially 
introduced into a stirred vessel, heated to 80.degree. C., and 22.1 g of 
salt-free C.I. Pigment Violet 23 were added at this temperature over a 
period of 1/2 hour. 32.0 g of hydroxymethylsaccharin were then added, the 
mixture was heated to 120.degree. C. and stirred at this temperature for 
another 5 hours. The solution was then poured into 3000 g of ice water, 
the product was filtered off with suction and washed with water until 
neutral. The filter residue was stirred with 750 g of 1% sodium hydroxide 
solution, stirred for another hour, filtered off with suction, washed with 
water until neutral and dried, giving 34.5 g of the dispersant of the 
formula (XI). 
Analysis: Calculated: C, 62.1%; H, 3.3%; N, 8.7%; Cl, 7.7%; S, 5.9%. Found: 
C, 59.0%; H, 4.0%; N, 8.0%; Cl, 6.9%; S, 4.7%. 
EXAMPLE 10a 
75 g of 85% isobutanol, 50 g of finely divided mill base composed of C.I. 
Pigment Violet 23 (containing 22% of salt from the synthesis, prepared 
according to U.S. Pat. No. 4,253,839 0.5 g of the dispersant of the 
formula (XI), 2.5 g of 50% alkylphenol polyglycol ether sulfate and 2.5 g 
of 98% formic acid were introduced in succession into a stirred vessel and 
the mixture was stirred at 25.degree. C. for 20 hours. During this time, 
another 75 g of 85% isobutanol were added dropwise. 300 ml of water were 
then added, and the mixture was heated to boiling for 5 hours. The 
isobutanol was then distilled off and the pigment preparation was filtered 
off with suction, washed until neutral and dried, giving 37.9 g of pigment 
preparation which, upon incorporation in nitrocellulose-based printing 
ink, gave transparent prints of high color strength and gloss.