DIKETOPYRROLOPYRROLE PIGMENT COMPOUND HAVING HIGH WEATHERING RESISTANCE, PREPARATION METHOD THERFOR, AND USE THEROF

Abstract

A diketopyrrolopyrrole pigment compound having high weather resistance, a preparation method therefor and a use thereof, which relate to the technical field of organic pigments. The diketopyrrolopyrrole pigment compound has the structural formula (I).

##STR00001##

The described diketopyrrolopyrrole pigment compound may be directly used as a wet filter cake, or may be further formed into a flowing solid powder or granulated into a granulated preparation. In the various applications described, the diketopyrrolopyrrole pigment compound exhibits high saturation, good rheology, hiding power, and gloss, high tint strength, and particularly high weather resistance. The diketopyrrolopyrrole pigment compound having high weather resistance, the preparation method therefor and the use thereof have good market prospects.

Claims

1. A diketopyrrolopyrrole pigment compound having high weathering resistance, wherein the diketopyrrolopyrrole pigment compound has the structural formula (I): ##STR00022## wherein, at least one electron-withdrawing group α in R.sub.1-R.sub.5 is one selected from the group consisting of halogen, cyano, carbonyl, carboxyl, ester, nitryl, sulfo; and at least one group of remaining groups in R.sub.1-R.sub.5 is one selected from the group consisting of H, C1-C30 alkyl, C6-C30 aryl, C5-C30 heteroaryl; at least one electron-withdrawing group β in R.sub.6-R.sub.10 is one selected from the group consisting of halo, cyano, carbonyl, carboxyl, ester, nitryl, sulfo; and at least one group of remaining groups in R.sub.6-R.sub.10 is one selected from the group consisting of H, C1-C30 alkyl, C6-C30 aryl, C5-C30 heteroaryl; and the type and number of the electron-withdrawing group α in R.sub.1-R.sub.5 are the same as those of the electron-withdrawing group β in R.sub.6-R.sub.10, and the type and number of the remaining groups in R.sub.1-R.sub.5 are also the same as those of the remaining groups in R.sub.6-R.sub.10.

2. (canceled)

3. The diketopyrrolopyrrole pigment compound having high weathering resistance of claim 1, wherein the C1-C30 alkyl is one selected from the group consisting of methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, cyclopropyl, cyclopentyl, cyclohexyl, dodecyl, octadecyl.

4. The diketopyrrolopyrrole pigment compound having high weathering resistance of claim 1, wherein the C6-C30 aryl is one selected from the group consisting of phenyl, biphenyl, naphthyl, phenanthryl, anthracenyl, and indenyl.

5. The diketopyrrolopyrrole pigment compound having high weathering resistance of claim 1, wherein the C5-C30 heteroaryl is one selected from the group consisting of furanyl, pyrrolyl, thiophenyl, pyridinyl, quinolyl, and isoquinolyl.

6-21. (canceled)

22. A method for preparing a diketopyrrolopyrrole pigment compound having high weathering resistance, comprising: S1, mixing and reacting succinic acid diester with nitrile (II), and nitrile (III) in an organic solvent in the presence of alkali at a temperature of 60° C. to 180° C. to obtain a pigment alkali metal salt intermediate; wherein the nitrile (II) is represented by the formula: ##STR00023## and the nitrile (III) is represented by the formula ##STR00024## S2, mixing the pigment alkali metal salt intermediate with a hydrolysis solution, and performing hydrolysis at a temperature of −20° C. to 180° C., and performing post-treatment to obtain the diketopyrrolopyrrole pigment compound having high weathering resistance; wherein the diketopyrrolopyrrole pigment compound has the structural formula (I): ##STR00025## wherein, at least one electron-withdrawing group α in R.sub.1-R.sub.5 is one selected from the group consisting of halogen, cyano, carbonyl, carboxyl, ester, nitryl, sulfo; and at least one group of remaining groups in R.sub.1-R.sub.5 is one selected from the group consisting of H, C1-C30 alkyl, C6-C30 aryl, C5-C30 heteroaryl; at least one electron-withdrawing group β in R.sub.6-R.sub.10 is one selected from the group consisting of halo, cyano, carbonyl, carboxyl, ester, nitryl, sulfo; and at least one group of remaining groups in R.sub.6-R.sub.10 is one selected from the group consisting of H, C1-C30 alkyl, C6-C30 aryl, C5-C30 heteroaryl; and the type and number of the electron-withdrawing group α in R.sub.1-R.sub.5 are the same as those of the electron-withdrawing group β in R.sub.6-R.sub.10, and the type and number of the remaining groups in R.sub.1-R.sub.5 are also the same as those of the remaining groups in R.sub.6-R.sub.10; or wherein the diketopyrrolopyrrole pigment compound has the structural formula (I): ##STR00026## wherein, at least one electron-withdrawing group α in R.sub.1-R.sub.5 is one selected from the group consisting of halogen, cyano, carbonyl, carboxyl, ester, nitryl, sulfo; and at least one group of remaining groups in R.sub.1-R.sub.5 is one selected from the group consisting of H, C1-C30 alkyl, C6-C30 aryl, C5-C30 heteroaryl; at least one electron-withdrawing group β in R.sub.6-R.sub.10 is one selected from the group consisting of halo, cyano, carbonyl, carboxyl, ester, nitryl, sulfo; and at least one group of remaining groups in R.sub.6-R.sub.10 is one selected from the group consisting of H, C1-C30 alkyl, C6-C30 aryl, C5-C30 heteroaryl, and the type and number of the electron-withdrawing group α in R.sub.1-R.sub.5 are the same as those of the electron-withdrawing group β in R.sub.6-R.sub.10, and the type and number of the remaining groups in R.sub.1-R.sub.5 are also the same as those of the remaining groups in R.sub.6-R.sub.10, wherein the C1-C30 alkyl is one selected from the group consisting of methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, cyclopropyl, cyclopentyl, cyclohexyl, dodecyl, octadecyl; or wherein the diketopyrrolopyrrole pigment compound has the structural formula (I): ##STR00027## wherein, at least one electron-withdrawing group α in R.sub.1-R.sub.5 is one selected from the group consisting of halogen, cyano, carbonyl, carboxyl, ester, nitryl, sulfo; and at least one group of remaining groups in R.sub.1-R.sub.5 is one selected from the group consisting of H, C1-C30 alkyl, C6-C30 aryl, C5-C30 heteroaryl; at least one electron-withdrawing group β in R.sub.6-R.sub.10 is one selected from the group consisting of halo, cyano, carbonyl, carboxyl, ester, nitryl, sulfo; and at least one group of remaining groups in R.sub.6-R.sub.10 is one selected from the group consisting of H, C1-C30 alkyl, C6-C30 aryl, C5-C30 heteroaryl; and the type and number of the electron-withdrawing group α in R.sub.1-R.sub.5 are the same as those of the electron-withdrawing group β in R.sub.6-R.sub.10, and the type and number of the remaining groups in R.sub.1-R.sub.5 are also the same as those of the remaining groups in R.sub.6-R.sub.10; wherein the C6-C30 aryl is one selected from the group consisting of phenyl, biphenyl, naphthyl, phenanthryl, anthracenyl, and indenyl; or wherein the diketopyrrolopyrrole pigment compound has the structural formula (I): ##STR00028## wherein, at least one electron-withdrawing group α in R.sub.1-R.sub.5 is one selected from the group consisting of halogen, cyano, carbonyl, carboxyl, ester, nitryl, sulfo; and at least one group of remaining groups in R.sub.1-R.sub.5 is one selected from the group consisting of H, C1-C30 alkyl, C6-C30 aryl, C5-C30 heteroaryl; at least one electron-withdrawing group β in R.sub.6-R.sub.10 is one selected from the group consisting of halo, cyano, carbonyl, carboxyl, ester, nitryl, sulfo; and at least one group of remaining groups in R.sub.6-R.sub.10 is one selected from the group consisting of H, C1-C30 alkyl, C6-C30 aryl, C5-C30 heteroaryl; and the type and number of the electron-withdrawing group α in R.sub.1-R.sub.5 are the same as those of the electron-withdrawing group β in R.sub.6-R.sub.10, and the type and number of the remaining groups in R.sub.1-R.sub.5 are also the same as those of the remaining groups in R.sub.6-R.sub.10; wherein the C5-C30 heteroaryl is one selected from the group consisting of furanyl, pyrrolyl, thiophenyl, pyridinyl, quinolyl, and isoquinolyl.

23. The preparation method of claim 22, wherein a ratio of the weight of the organic solvent to the weight of the reactant is in a range from 2:1 to 50:1, and a molar ratio of the alkali to the succinic acid diester is in a range from 0.5:1 to 10:1.

24. The preparation method of claim 23, wherein the succinic acid diester is one selected from the group consisting of dialkyl succinate, diaryl succinate, and monoalkyl monoaryl succinate.

25. The preparation method of claim 24, wherein the dialkyl succinate is one selected from the group consisting of dimethyl succinate, diethyl succinate, diisopropyl succinate, di-tert-butyl succinate, diamyl succinate, and dicyclohexyl succinate.

26. The preparation method of claim 23, wherein the organic solvent is one selected from the group consisting of an alcohol solvent, an ether solvent, and a polar aprotic solvent, or combinations thereof.

27. (canceled)

28. The preparation method of claim 26, wherein the alcohol solvent is one selected from the group consisting of diethyl ether, methyl tert-butyl ether, tetrahydrofuran, and 2-methyltetrahydrofuran, or combinations thereof.

29. The preparation method of claim 26, wherein the polar aprotic solvent is one selected from the group consisting of N, N-dimethylformamide, N, N-Dimethylacetamide, N-methylpyrrolidone, and dimethyl sulfoxide (DMSO), or combinations thereof.

30. The preparation method of claim 23, wherein the alkali is one selected from the group consisting of alkali metal, alkali amide, alkali metal hydride, alkali metal alkoxide.

31. The preparation method of claim 23, wherein the hydrolysis solution is one selected from the group consisting of water, alcohol, acid, or combinations thereof.

32. The preparation method of claim 22, wherein the post-treatment comprises the step of: performing heat treatment in water or the organic solvent or a mixture thereof at a temperature of 50° C. to 200° C. for 10 min to 8 h, and performing grinding process before, during, or after the post-treatment.

33. A use of a diketopyrrolopyrrole pigment compound having high weathering resistance, wherein the pigment compound is in the form of wet filter cakes, solid powers or granular formulations to be applicable for the coloring of plastics, resins, coating compositions, paints, printing inks, inkjet inks, electrophotographic toners, developers, and liquid crystals, and the pigment compound is orange; wherein the diketopyrrolopyrrole pigment compound has the structural formula (I): ##STR00029## wherein, at least one electron-withdrawing group α in R.sub.1-R.sub.5 is one selected from the group consisting of halogen, cyano, carbonyl, carboxyl, ester, nitryl, sulfo; and at least one group of remaining groups in R.sub.1-R.sub.5 is one selected from the group consisting of H, C1-C30 alkyl, C6-C30 aryl, C5-C30 heteroaryl; at least one electron-withdrawing group β in R.sub.6-R.sub.10 is one selected from the group consisting of halo, cyano, carbonyl, carboxyl, ester, nitryl, sulfo; and at least one group of remaining groups in R.sub.6-R.sub.10 is one selected from the group consisting of H, C1-C30 alkyl, C6-C30 aryl, C5-C30 heteroaryl; and the type and number of the electron-withdrawing group α in R.sub.1-R.sub.5 are the same as those of the electron-withdrawing group β in R.sub.6-R.sub.10, and the type and number of the remaining groups in R.sub.1-R.sub.5 are also the same as those of the remaining groups in R.sub.6-R.sub.10; or wherein the diketopyrrolopyrrole pigment compound has the structural formula (I): ##STR00030## wherein, at least one electron-withdrawing group α in R.sub.1-R.sub.5 is one selected from the group consisting of halogen, cyano, carbonyl, carboxyl, ester, nitryl, sulfo; and at least one group of remaining groups in R.sub.1-R.sub.5 is one selected from the group consisting of H, C1-C30 alkyl, C6-C30 aryl, C5-C30 heteroaryl; at least one electron-withdrawing group β in R.sub.6-R.sub.10 is one selected from the group consisting of halo, cyano, carbonyl, carboxyl, ester, nitryl, sulfo; and at least one group of remaining groups in R.sub.6-R.sub.10 is one selected from the group consisting of H, C1-C30 alkyl, C6-C30 aryl, C5-C30 heteroaryl; and the type and number of the electron-withdrawing group α in R.sub.1-R.sub.5 are the same as those of the electron-withdrawing group β in R.sub.6-R.sub.10, and the type and number of the remaining groups in R.sub.1-R.sub.5 are also the same as those of the remaining groups in R.sub.6-R.sub.10, wherein the C1-C30 alkyl is one selected from the group consisting of methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, cyclopropyl, cyclopentyl, cyclohexyl, dodecyl, octadecyl; or wherein the diketopyrrolopyrrole pigment compound has the structural formula (I): ##STR00031## wherein, at least one electron-withdrawing group α in R.sub.1-R.sub.5 is one selected from the group consisting of halogen, cyano, carbonyl, carboxyl, ester, nitryl, sulfo; and at least one group of remaining groups in R.sub.1-R.sub.5 is one selected from the group consisting of H, C1-C30 alkyl, C6-C30 aryl, C5-C30 heteroaryl; at least one electron-withdrawing group β in R.sub.6-R.sub.10 is one selected from the group consisting of halo, cyano, carbonyl, carboxyl, ester, nitryl, sulfo; and at least one group of remaining groups in R.sub.6-R.sub.10 is one selected from the group consisting of H, C1-C30 alkyl, C6-C30 aryl, C5-C30 heteroaryl; and the type and number of the electron-withdrawing group α in R.sub.1-R.sub.5 are the same as those of the electron-withdrawing group β in R.sub.6-R.sub.10, and the type and number of the remaining groups in R.sub.1-R.sub.5 are also the same as those of the remaining groups in R.sub.6-R.sub.10; wherein the C6-C30 aryl is one selected from the group consisting of phenyl, biphenyl, naphthyl, phenanthryl, anthracenyl, and indenyl; or wherein the diketopyrrolopyrrole pigment compound has the structural formula (I): ##STR00032## wherein, at least one electron-withdrawing group α in R.sub.1-R.sub.5 is one selected from the group consisting of halogen, cyano, carbonyl, carboxyl, ester, nitryl, sulfo; and at least one group of remaining groups in R.sub.1-R.sub.5 is one selected from the group consisting of H, C1-C30 alkyl, C6-C30 aryl, C5-C30 heteroaryl; at least one electron-withdrawing group β in R.sub.6-R.sub.10 is one selected from the group consisting of halo, cyano, carbonyl, carboxyl, ester, nitryl, sulfo; and at least one group of remaining groups in R.sub.6-R.sub.10 is one selected from the group consisting of H, C1-C30 alkyl, C6-C30 aryl, C5-C30 heteroaryl; and the type and number of the electron-withdrawing group α in R.sub.1-R.sub.5 are the same as those of the electron-withdrawing group β in R.sub.6-R.sub.10, and the type and number of the remaining groups in R.sub.1-R.sub.5 are also the same as those of the remaining groups in R.sub.6-R.sub.10; wherein the C5-C30 heteroaryl is one selected from the group consisting of furanyl, pyrrolyl, thiophenyl, pyridinyl, quinolyl, and isoquinolyl.

Description

EXAMPLE 1

[0051] 8.2 mol anhydrous tert-amyl alcohol is added to a four-neck flask. After 3.5 mol sodium is added to the solution in the flask, the mixture is stirred under reflux until the sodium is completely reacted. 1.1 mol 3,5-dicyano-4-methylbenzonitrile is added to the reaction mixture at a temperature of 100° C. 1.6 mol diisopropyl succinate is added dropwise to the mixture at a temperature of 100° C. in an hour, following by mixing the mixture under reflux for 4 hours. After the reaction suspension is cooled to 80° C., the cooled reaction suspension is poured into a mixture of 500 ml water and 800 ml methanol at a temperature of 25° C. The hydrolyzed suspension is stirred under reflux for 6.5 hours, and acetic acid is added dropwise to the suspension to make the suspension neural. The suspension is filtered after it is cooled to room temperature, and the pigment is washed with 500 ml methanol and 1000 ml water. The wet filter cake is dried in an 80° C. vacuum oven until the moisture content is less than 0.1%. Finally, the dried filter cake is grinded to obtain 206 g diketopyrrolopyrrole pigment of formula (I-1).

##STR00013##

[0052] Elemental analysis: C, 68.66%; H, 2.71%; N, 19.57%.

[0053] MS(Maldi-ToF, positive mode): m/z 417.2 (100%), 418.2 (30.5%) 419.2 (7.8%).

EXAMPLE 2

[0054] 8.0 mol anhydrous tert-amyl alcohol is added to a four-neck flask. After 4.0 mol sodium is added to the solution in the flask, and the mixture is stirred under reflux until the sodium is completely reacted. 1.0 mol 3,5-dibromo-4-ethylbenzonitrile is added to the reaction mixture at a temperature of 100° C. 1.5 mol di-tert-amyl succinate is added dropwise to the mixture at a temperature of 100° C. in an hour, following by mixing the mixture under reflux for 4 hours. After the reaction suspension is cooled to 80° C., the cooled reaction suspension is poured into a mixture of 600 ml water and 600 ml methanol at a temperature of 25° C. The hydrolyzed suspension is stirred under reflux for 5.5 hours, and acetic acid is added dropwise to the suspension to make the suspension neural. The suspension is filtered after it is cooled to room temperature, and the pigment is washed with 500 ml methanol and 800 ml water. The wet filter cake is dried in an 80° C. vacuum oven until the moisture content is less than 0.1%. Finally, the dried filter cake is grinded to obtain 279 g diketopyrrolopyrrole pigment of formula (I-2).

##STR00014##

[0055] Elemental analysis: C, 39.55%; H, 2.63%; N, 4.17%; Br, 47.69%.

[0056] MS(Maldi-ToF, positive mode): m/z 660.6 (100%), 662.6 (66.5%), 658.6 (55.2%).

EXAMPLE 3

[0057] 8.0 mol anhydrous tert-amyl alcohol is added to a four-neck flask. After 3.4 mol sodium is added to the solution in the flask, the mixture is stirred under reflux until the sodium is completely reacted. 1.2 mol 3-iodo-4-isopropylbenzonitrile is added to the reaction mixture at a temperature of 100° C. 1.2 mol di-tert-butyl succinate is added dropwise to the mixture at a temperature of 100° C. in half an hour, following by mixing the mixture under reflux for 4 hours. After the reaction suspension is cooled to 80° C., the cooled reaction suspension is poured into a mixture of 800 ml water and 500 ml methanol at a temperature of 25° C. The hydrolyzed suspension is stirred under reflux for 5.5 hours, and acetic acid is added dropwise to the suspension to make the suspension neural. The suspension is filtered after it is cooled to room temperature, and the pigment is washed with 500 ml methanol and 800 ml water. The wet filter cake is dried in an 80° C. vacuum oven until the moisture content is less than 0.1%. Finally, the dried filter cake is grinded to obtain 337 g diketopyrrolopyrrole pigment of formula (I-3).

##STR00015##

[0058] Elemental analysis: C, 47.52%; H, 3.75%; N, 4.61%; I, 41.19%.

[0059] MS(Maldi-ToF, positive mode): m/z 624.7 (100%), 625.7 (30.9%), 626.7 (5.5%).

EXAMPLE 4

[0060] 16.0 mol anhydrous tert-amyl alcohol is added to a four-neck flask. After 7.2 mol sodium is added to the solution in the flask, the mixture is stirred under reflux until the sodium is completely reacted. 2 mol 3,6-difluoro-4-phenylbenzonitrile is added to the reaction mixture at a temperature of 100° C. 1.5 mol diisopropyl succinate is added dropwise to the mixture at a temperature of 100° C. in half an hour, following by mixing the mixture under reflux for 4 hours. After the reaction suspension is cooled to 80° C., the cooled reaction suspension is poured into a mixture of 1200 ml water and 800 ml methanol at a temperature of 25° C. The hydrolyzed suspension is stirred under reflux for 5.5 hours. The suspension is filtered after it is cooled to room temperature, and the pigment is washed with 900 ml methanol and 1500 ml water. The wet filter cake is dried in an 80° C. vacuum oven until the moisture content is less than 0.1%. Finally, the dried filter cake is grinded to obtain 460 g diketopyrrolopyrrole pigment of formula (I-4).

##STR00016##

[0061] Elemental analysis: C, 70.22%; H, 3.33%; N, 5.39%; F, 15.06%.

[0062] MS(Maldi-ToF, positive mode): m/z 513.3 (100%), 514.3 (30.9%), 515.3 (5.5%).

EXAMPLE 5

[0063] 16.0 mol anhydrous tert-amyl alcohol is added to a four-neck flask. After 7.2 mol sodium is added to the solution in the flask, the mixture is stirred under reflux until the sodium is completely reacted. 3 mol 2-bromo-4-n-dodecyl-6-chlorobenzonitrile is added to the reaction mixture at a temperature of 100° C. 1.9 mol di-tert-butyl succinate is added dropwise to the mixture at a temperature of 100° C. in half an hour, following by mixing the mixture under reflux for 4 hours. After the reaction suspension is cooled to 80° C., the cooled reaction suspension is poured into a mixture of 1500 ml water and 1000 ml methanol at a temperature of 25° C. The hydrolyzed suspension is stirred under reflux for 5.5 hours. The suspension is filtered after it is cooled to room temperature, and the pigment is washed with 900 ml methanol and 1500 ml water. The wet filter cake is dried in a 100° C. vacuum oven until the moisture content is less than 0.1%. Finally, the dried filter cake is grinded to obtain 1085 g diketopyrrolopyrrole pigment of formula (I-5).

##STR00017##

[0064] Elemental analysis: C, 58.77%; H, 6.51%; N, 3.46%; Br, 18.95%; Cl, 8.01%.

[0065] MS(Maldi-ToF, positive mode): m/z 851.3 (100%), 853.3 (78.6%), 852.3 (50.5%).

EXAMPLE 6

[0066] 4.2 mol anhydrous tert-amyl alcohol is added to a four-neck flask. After 1.8 mol sodium is added to the solution in the flask, the mixture is stirred under reflux until the sodium is completely reacted. 1 mol 3,5-dibromo-4-n-octadecylbenzonitrile is added to the reaction mixture at a temperature of 100° C. 0.6 mol diisopropyl succinate is added dropwise to the mixture at a temperature of 100° C. in 0.3 hour, following by mixing the mixture under reflux for 6 hours. After the reaction suspension is cooled to 80° C., the cooled reaction suspension is poured into a mixture of 500 ml water and 800 ml methanol at a temperature of 25° C. The hydrolyzed suspension is stirred under reflux for 6 hours, and acetic acid is added dropwise to the suspension to make the suspension neural. The suspension is filtered after it is cooled to room temperature, and the pigment is washed with 500 ml methanol and 1000 ml water. The wet filter cake is dried in a 100° C. vacuum oven until the moisture content is less than 0.1%. Finally, the dried filter cake is grinded to obtain 502 g diketopyrrolopyrrole pigment of formula (I-6).

##STR00018##

[0067] Elemental analysis: C, 59.27%; H, 7.38%; N, 2.60%; Br, 28.73%.

[0068] MS(Maldi-ToF, positive mode): m/z 1109.5 (100%), 1107.3 (62.2%), 1111.3 (58.7%).

EXAMPLE 7

[0069] 4.2 mol anhydrous tert-amyl alcohol is added to a four-neck flask. After 1.7 mol sodium is added to the solution in the flask, the mixture is stirred under reflux until the sodium is completely reacted. 1 mol 3-chloro-4-tert-butylbenzonitrile is added to the reaction mixture at a temperature of 100° C. 0.65 mol di-tert-butyl succinate is added dropwise to the mixture at a temperature of 100° C. in half an hour, following by mixing the mixture under reflux for 5 hours. After the reaction suspension is cooled to 80° C., the cooled reaction suspension is poured into a mixture of 500 ml water and 800 ml methanol at a temperature of 25° C. The hydrolyzed suspension is stirred under reflux for 5 hours. The suspension is filtered after it is cooled to room temperature, and the pigment is washed with 500 ml methanol and 1000 ml water. The wet filter cake is dried in a 100° C. vacuum oven until the moisture content is less than 0.1%. Finally, the dried filter cake is grinded to obtain 211 g diketopyrrolopyrrole pigment of formula (I-7).

##STR00019##

[0070] Elemental analysis: C, 65.52%; H, 5.51%; N, 6.19%; Cl, 15.55%.

[0071] MS(Maldi-ToF, positive mode): m/z 469.2 (100%), 470.2 (47.8%). 468.2 (46.7%).

EXAMPLE 8

[0072] 8.5 mol anhydrous tert-amyl alcohol is added to a four-neck flask. After 3.5 mol sodium is added to the solution in the flask, the mixture is stirred under reflux until the sodium is completely reacted. 2 mol 3-iodo-4-ethyl-6-fluorobenzonitrile is added to the reaction mixture at a temperature of 100° C. 1.5 mol di-tert-amyl succinate is added dropwise to the mixture at a temperature of 100° C. in an hour, following by mixing the mixture under reflux for 8 hours. After the reaction suspension is cooled to 80° C., the cooled reaction suspension is poured into a mixture of 1000 ml water and 1500 ml methanol at a temperature of 25° C. The hydrolyzed suspension is stirred under reflux for 5 hours, and acetic acid is added dropwise to the suspension to make the suspension neural. The suspension is filtered after it is cooled to room temperature, and the pigment is washed with 800 ml methanol and 1500 ml water. The wet filter cake is dried in a 130° C. vacuum oven until the moisture content is less than 0.1%. Finally, the dried filter cake is grinded to obtain 569 g diketopyrrolopyrrole pigment of formula (I-8).

##STR00020##

[0073] Elemental analysis: C, 42.83%; H, 2.85%; N, 4.47%; I, 41.03%; F, 6.26%.

[0074] MS(Maldi-ToF, positive mode): m/z 632.9 (100%), 633.9 (28.5%), 634.9 (9.6%).

EXAMPLE 9

[0075] 10 mol anhydrous tert-amyl alcohol is added to a four-neck flask. After 4 mol sodium is added to the solution in the flask, the mixture is stirred under reflux until the sodium is completely reacted. 2 mol 2,6-dicyano-4-phenylbenzonitrile is added to the reaction mixture at a temperature of 100° C. 1.8 mol diisopropyl succinate is added dropwise to the mixture at a temperature of 100° C. in an hour, following by mixing the mixture under reflux for 10 hours. After the reaction suspension is cooled to 80° C., the cooled reaction suspension is poured into a mixture of 1000 ml water and 1500 ml methanol at a temperature of 25° C. The hydrolyzed suspension is stirred under reflux for 8 hours. The suspension is filtered after it is cooled to room temperature, and the pigment is washed with 800 ml methanol and 1500 ml water. The wet filter cake is dried in a 130° C. vacuum oven until the moisture content is less than 0.1%. Finally, the dried filter cake is grinded to obtain 460 g diketopyrrolopyrrole pigment of formula (I-9).

##STR00021##

[0076] Elemental analysis: C, 76.60%; H, 3.06%; N, 14.96%.

[0077] MS(Maldi-ToF, positive mode): m/z 541.2 (100%), 542.2 (44.1%), 543.2 (12.1%).

[0078] Weathering Resistance Test

EXAMPLE 10

[0079] The above-mentioned pigments are made into color cards according to the following methods, respectively, and a color paste is prepared from the following components in percentage by weight: 71% of water, 8% of BYK190, 1% of BYK021, and 20% of a pigment.

[0080] The method is as follows: the color paste is formulated proportionally as described, 1-1.2 mm zirconium beads are added. The mixture is stirred with a mixer at a high shear rate (at 1800-2100 rmp) for 120 minutes to well disperse the pigment, so that the pigment added can be dispersed into primitive particles; then it is filtered to obtain the color paste.

[0081] The color paste is diluted with Nippon water-based latex white paint (Nippon Odour-less 120) at a ratio of 10:1. The diluted coating is scraped onto a white cardboard and dried at a temperature of 80° C. for 30 minutes to obtain a color card for the weathering resistance test.

[0082] The color card of each sample is cut into two equal halves with a scissor, wherein a half of the A color card is sealed and stored, and the other half of the B color card is exposed to the outdoors for 3 months. The coloring strength of the B color card is tested based on the A color card, and the test result is shown in Table 1-1. The closer the coloring strength is to 100%, the better the wreathing resistance, and the lower the color strength, the worse the wreathing resistance. It can be seen from the Table 1-1 that the weathering resistance of the orange diketopyrrolopyrrole pigment according to the present invention is improved when compared with the sample pigment orange 73.

TABLE-US-00001 TABLE 1-1 Coloring strength after exposure to outdoors Sample for 3 months Pigment orange 73 51.80% Example 1 83.20% Example 2 82.60% Example 3 75.01% Example 4 80.50% Example 5 76.20% Example 6 80.60% Example 7 77.00% Example 8 82.50% Example 9 82.50%

EXAMPLE 11

[0083] Based on the Example 10, the B color card is exposed to the outdoors for 6 months extended from the previous 3 months, and other operations remain the same. Then the coloring strength of the B color card is tested based on the A color card, and the test result is shown in Table 1-2. It can be seen from the Table 1-2 that the weathering resistance of the orange diketopyrrolopyrrole pigment according to the present invention is improved when compared with the sample pigment orange 73. In addition, due to the exposure time is extended to 6 months, the weathering resistance varies greatly, and it is clear that the compound (I-7) exhibits the optimum weathering resistance.

TABLE-US-00002 TABLE 1-2 Coloring strength after exposure to outdoors Sample for 6 months Pigment orange 73 32.30% Example 1 53.12% Example 2 51.80% Example 3 46.32% Example 4 51.73% Example 5 47.11% Example 6 51.20% Example 7 65.10% Example 8 53.09% Example 9 51.56%

EXAMPLE 12

[0084] On the basis of Example 10, the following experimental conditions are changed while other operations remain the same:

[0085] the B color card is placed in an artificial accelerated aging instrument (Ci5000 type xenon lamp climate tester produced by American ATLAS company) for 720 hours. Conditions for the instrument: irradiance (340 nm) 0.35 W/m.sup.2, relative humidity 50%, black standard temperature (65±2) ° C., rainfall cycle 18 min/102 min. Then the coloring strength of the B color card is tested based on the A color card, and the test result is shown in Table 1-3. It can be seen from the data in Table 1-3 that the weathering resistance of the orange diketopyrrolopyrrole pigment according to the present invention is greatly improved when compared with the sample pigment orange 73, and the compound (I-7) exhibits the optimum weathering resistance.

TABLE-US-00003 TABLE 1-3 Placed in an artificial accelerated aging instrument Sample for 720 hours Pigment orange 73 41.50% Example 1 66.31% Example 2 66.65% Example 3 61.44% Example 4 66.68% Example 5 63.21% Example 6 66.85% Example 7 71.61% Example 8 66.78% Example 9 67.99%

[0086] The above descriptions are only the preferred embodiments of the invention, not thus limiting the embodiments and scope of the invention. Those skilled in the art should be able to realize that the schemes obtained from the content of specification and drawings of the invention are within the scope of the invention.