LITHOGRAPHIC PRINTING INK, VARNISH FOR LITHOGRAPHIC INKS, AND METHOD FOR PRODUCING PRINTED MATTER USING SAID INK

Abstract

A lithographic ink which has a highly sensitive curability for active energy beam simultaneously with a high washability with water, and which also has excellent resistance to surface staining in the printing and high water resistance of the cured film is provided. Also provided are a varnish for such lithographic ink and a method for producing printed material. The lithographic ink comprises (a) a pigment and (b) a resin having an ethylenically unsaturated group and a hydrophilic group, and it has a highly sensitive curability for active energy beam simultaneously with a high washability with water, and also, excellent resistance to surface staining in the printing and high water resistance of the cured film.

Claims

1. A lithographic ink comprising (a) a pigment and (b) a resin having an ethylenically unsaturated group and a hydrophilic group.

2. (canceled)

3. A lithographic ink according to claim 1 wherein the hydrophilic group of the resin (b) having an ethylenically unsaturated group and a hydrophilic group includes at least one functional group selected from carboxyl group, sulfo group, phosphate group, hydroxy group, and amino group.

4-16. (canceled)

17. A lithographic ink according to claim 1 further comprising (g) a pigment dispersant.

18. A lithographic ink according to claim 17 wherein the pigment dispersant (g) has an acidic group.

19. A lithographic ink according to claim 17 wherein the pigment dispersant (g) has at least one functional group selected from carboxyl group, sulfo group, and phosphate group.

20. A lithographic ink according to claim 18 wherein the pigment dispersant (g) has an acid value of 5 to 200 mgKOH/g.

21. A lithographic ink according to claim 18 wherein the pigment dispersant (g) also has a basic group.

22. A lithographic ink according to claim 18 wherein the pigment dispersant (g) has amino group.

23. A lithographic ink according to claim 21 wherein the pigment dispersant (g) has an amine value of 5 to 50 mgKOH/g.

24. A lithographic ink according to claim 17 wherein content of the pigment dispersant (g) is 5 to 50 mass % in relation to 100 mass % of the pigment (a).

25. A lithographic ink according to claim 1 wherein the pigment (a) is a water-insoluble salt, an azo lake pigment, a metal complex, or carbon black.

26-28. (canceled)

29. A lithographic ink according to claim 25, wherein the carbon black has an acidic group.

30. A lithographic ink according to claim 29 wherein the carbon black has an average particle diameter of 10 to 50 nm.

31. A lithographic ink according to claim 29 wherein dibutyl phthalate absorption per 100 g of the carbon black is 40 to 80 cm.sup.3/100 g.

32-36. (canceled)

37. A method for producing a printed material using the lithographic ink according to claim 1.

38. (canceled)

39. A method for producing a printed material comprising the step of printing the lithographic ink according to claim 1 on a substrate by using a waterless lithography plate.

40. A method for producing a printed material comprising the step of printing the lithographic ink according to claim 1 on a substrate by using a water lithography plate.

41. A method for producing a printed material according to claim 39 further comprising the step of conducing irradiation with an active energy beam.

42. A method for producing a printed material according to claim 40 wherein the substrate comprises at least one member selected from plastic film, plastic film laminate paper, metal, metal-vapor-deposited paper, and metal-vapor-deposited plastic film.

43. (canceled)

Description

EXAMPLES

[0152] Next, the present invention is described in detail by referring to Examples which by no means limit the scope of the present invention.

[0153] Pigment I: Seika cyanine blue (manufactured by Dainichiseika Color & Chemicals Mfg. Co., Ltd.)

[0154] Resin I: 0.6 equivalent weight of glycidyl methacrylate (GMA) was reacted (addition reaction) with the carboxyl group of a copolymer comprising 25 mass % of methyl methacrylate, 25 mass % of styrene, and 50 mass % of methacrylic acid to obtain resin I having an ethylenically unsaturated group and a hydrophilic group. The resulting resin I had a weight average molecular weight of 34,000, an acid value of 102 mgKOH/g, and an iodine number of 2.0 mol/kg.

[0155] Resin II: 0.95 equivalent weight of glycidyl methacrylate was reacted (addition reaction) with the carboxyl group of a copolymer comprising 25 mass % of methyl methacrylate, 25 mass % of styrene, and 50 mass % of methacrylic acid to obtain resin II. The resulting resin II had a weight average molecular weight of 39,000, an acid value of 10 mgKOH/g, and an iodine number of 3.1 mol/kg.

[0156] Resin III: 0.9 equivalent weight of glycidyl methacrylate was reacted (addition reaction) with the carboxyl group of a copolymer comprising 25 mass % of methyl methacrylate, 25 mass % of styrene, and 50 mass % of methacrylic acid to obtain resin III. The resulting resin III had a weight average molecular weight of 38,000, an acid value of 35 mgKOH/g, and an iodine number of 2.9 mol/kg.

[0157] Resin IV: 0.8 equivalent weight of glycidyl methacrylate was reacted (addition reaction) with the carboxyl group of a copolymer comprising 25 mass % of methyl methacrylate, 25 mass % of styrene, and 50 mass % of methacrylic acid to obtain resin IV. The resulting resin IV had a weight average molecular weight of 37,000, an acid value of 62 mgKOH/g, and an iodine number of 2.5 mol/kg.

[0158] Resin V: 0.4 equivalent weight of glycidyl methacrylate was reacted (addition reaction) with the carboxyl group of a copolymer comprising 25 mass % of methyl methacrylate, 25 mass % of styrene, and 50 mass % of methacrylic acid to obtain resin V. The resulting resin V had a weight average molecular weight of 32,000, an acid value of 190 mgKOH/g, and an iodine number of 1.0 mol/kg.

[0159] Resin VI: 0.2 equivalent weight of glycidyl methacrylate was reacted (addition reaction) with the carboxyl group of a copolymer comprising 25 mass % of methyl methacrylate, 25 mass % of styrene, and 50 mass % of methacrylic acid to obtain resin VI. The resulting resin VI had a weight average molecular weight of 31,000, an acid value of 240 mgKOH/g, and an iodine number of 0.5 mol/kg.

[0160] Resin VII: 0.1 equivalent weight of glycidyl methacrylate was reacted (addition reaction) with the carboxyl group of a copolymer comprising 25 mass % of methyl methacrylate, 25 mass % of styrene, and 50 mass % of methacrylic acid to obtain resin VII. The resulting resin VII had a weight average molecular weight of 30,000, an acid value of 259 mgKOH/g, and an iodine number of 0.25 mol/kg.

[0161] Resin VIII: A copolymer comprising 25 mass % of methyl acrylate, 25 mass % of styrene, and 50 mass % of methacrylic acid was obtained. The resulting resin VIII had a weight average molecular weight of 29,000, an acid value of 282 mgKOH/g, and an iodine number of 0 mol/kg.

[0162] Resin IX: 1.0 equivalent weight of glycidyl methacrylate (GMA) was reacted (addition reaction) with the carboxyl group of a copolymer comprising 25 mass % of methyl methacrylate, 25 mass % of styrene, and 50 mass % of methacrylic acid. The resulting resin IX had a weight average molecular weight of 40,000, an acid value of 0 mgKOH/g, and an iodine number of 3.2 mol/kg.

[0163] Reactive diluent I: Miramer (Registered Trademark) M340 (manufactured by Miwon)

[0164] Reactive diluent II: Miramer (Registered Trademark) M4004 (manufactured by Miwon)

[0165] Photopolymerization initiator I: IRGACURE (Registered Trademark) 907 (manufactured by BASF)

[0166] Sensitizing agent I: diethylaminobenzophenone (manufactured by Tokyo Chemical Industry Co., Ltd.)

[0167] Polymerization inhibitor I: p-methoxyphenol (manufactured by Wako Pure Chemical Industries, Ltd.)

[0168] Additive I: lauryl acrylate (manufactured by Wako Pure Chemical Industries, Ltd.)

[0169] Amine compound I: diethanolamine (manufactured by Tokyo Chemical Industry Co., Ltd.)

[0170] The weight average molecular weight of the resin is the value measured by gel permeation chromatography (GPC) using tetrahydrofuran for the mobile phase. The column used was Shodex KF-803, and the weight average molecular weight was calculated in terms of polystyrene.

[0171] A waterless lithography plate (TAN-E manufactured by Toray Industries, Inc.) was mounted on an offset press (Oliver 266EPZ manufactured by SAKURAI GRAPHIC SYSTEMS CORPORATION), and 10000 coated papers were printed by using inks respectively having the composition of Examples 1 to 8 and Comparative Examples 1 to 2 to evaluate the lithography adaptability and the printed material.

[0172] A photosensitive resin plate (Toreleaf (Registered Trademark) DWF95DIII manufactured by Toray Industries, Inc.) was mounted on a flexography tester (Flexiproof 100 manufactured by Print Coat Instruments Ltd.), and printing on a PET (polyethylene terephthalate) film (Novaclear (Registered Trademark) manufactured by Mitsubishi Chemical Corporation; thickness, 100 ?m) was conducted by using Anirox roll (line number, 400) and inks of Examples 9 to 11 and Comparative Examples 3 to 4.

[0173] Printing inks of Examples 12 to 14 and Comparative Examples 5 to 6 were printed on a PET (polyethylene terephthalate) film (Novaclear (Registered Trademark) manufactured by Mitsubishi Chemical Corporation; thickness, 100 ?m) by using a gravure tester GP-10 (manufactured by KURABO INDUSTRIES LTD.) having a helio gravure (175 lines/inch), and the inks were dried by using a dryer.

[0174] Printing inks of Examples 15 to 17 and Comparative Examples 7 to 8 were printed on a PET film (Novaclear (Registered Trademark) manufactured by Mitsubishi Chemical Corporation; thickness, 100 ?m) by using an ink-jet printer (manufactured by Canon Inc.) which has been modified.

[0175] The evaluation was conducted as described below.

(1) Sensitivity

[0176] The printed material was irradiated with UV by using a UV irradiation apparatus manufactured by Ushio (120 W/cm, 1 ultra-high metal halide lamp) under the condition of the belt conveyer speed of 0 to 150 m/min to determine the belt conveyer speed when the ink on the printed material became sufficiently cured such that the ink was no longer peelable when a cellophane adhesive tape (Sellotape (Registered Trademark) No. 405) was adhered onto the coated paper and then peeled from the coated paper. In this case, higher belt conveyer speed indicates higher sensitivity since the curing can be accomplished with reduced exposure. The sensitivity was evaluated insufficient when the belt conveyer speed was less than 100 m/min; good when the belt conveyer speed was at least 100 m/min and less than 120 m/min; and excellent when the belt conveyer speed was at least 120 m/min since the printed material having such sensitivity can be used in a power-saving UV printer.

(2) Washability with Water

[0177] Washing method A: the ink remaining on the roller of the printer after the lithography adaptability test using the inks having the composition shown in Examples 1 to 8 and Comparative Examples 1 to 2 was washed with water, and the washability of the ink with water was evaluated by 3 grades. [0178] 3: the ink was entirely removed by washing once with water [0179] 2: the ink was entirely removed by washing twice with water [0180] 1: the ink residue remained even after washing three times with water

[0181] Washing method B: the printing ink on the uncured or undried printed material was wiped off by using a cloth impregnated with 1 mass % aqueous solution of a commercially available basic detergent (Magiclean manufactured by Kao Corporation) (pH=10.5), and the washability of the ink with water was evaluated by 3 grades. [0182] 3: the ink was entirely removed by wiping once [0183] 2: the ink was entirely removed by wiping twice [0184] 1: the ink residue remained even after wiping three times

(3) Water Resistance of the Film

[0185] The ink cured film on the printed material was retained in water at 25? C., and the water resistance was evaluated by 3 grades. Elution of the ink into the water was visually confirmed. [0186] 3: no ink elution was observed before 24 hours [0187] 2: no ink elution was observed before 12 hours, but the ink was partly eluted within 24 hours [0188] 1: ink elution was observed before 12 hours

(4) Resistance to Surface Staining

[0189] Cyan density in the non-printing part of the printed material was evaluated for the case when the cyan density in the solid part was 2.0 by using a reflection densitometer (SpectroEye manufactured by GretagMacbeth). The resistance to surface staining was good when the reflected density was up to 0.5 and excellent when the reflected density was up to 0.3.

(5) Viscosity

[0190] A cone plate (cone angle, 1?; diameter, 40 mm) was mounted on Rheometer-MCR301 manufactured by Anton Paar, and the viscosity at 25? C. and 5 rpm was measured for 0.15 ml of the ink.

Example 1

[0191] Components of the ink composition shown in Table 1 were weighed and passed through gap 1 of a three roll mill EXAKT (Registered Trademark) M-80S (manufactured by EXAKT) three times to obtain the lithographic ink.

[0192] The resulting lithographic ink was subjected to the lithography adaptability test as described above to evaluate the sensitivity, the washability with water, the water resistance of the film, and resistance to surface staining. The results are shown in Table 1.

[0193] The thus prepared lithographic ink had an adequate viscosity of 51 Pa.Math.s. The sensitivity was excellent with the belt conveyer speed of 130 m/min. With regard to the washability with water, all remaining ink on the roller could be washed by one washing with water. With regard to the water resistance of the film, ink elution from the cured ink film in water at 25? C. was not recognized even after 24 hours. The resistance to surface staining was excellent with the reflection density in the non-printing area of 0.2.

Examples 2 to 7

[0194] The procedure of Example 1 was repeated except that the resin II to VII were used instead of the resin I and concentration of the ethylenically unsaturated group (iodine number) and concentration of the hydrophilic group (acid value) were as shown in Table 1 to evaluate the sensitivity, the washability with water, the water resistance of the film, and the resistance to surface staining. The sensitivity and the water resistance of the film tended to increase with increase in the concentration of the ethylenically unsaturated group and the washability with water and the resistance to the surface staining tended to improve with the increase in the concentration of the hydrophilic group. As a lithographic ink having the sensitivity, the washability with water, the water resistance of the film, and the resistance to the surface staining, preferable results were realized in Examples 3 to 6, and more preferable results were realized in Examples 4 and 5.

Example 8

[0195] The procedure of Example 1 was repeated except that lauryl acrylate was added as an additive to evaluate the sensitivity, the washability with water, the water resistance, and resistance to surface staining. The thus prepared lithographic ink had an adequate viscosity of 47 Pa.Math.s. The sensitivity was excellent with the belt conveyer speed of 125 m/min. With regard to the washability with water, all remaining ink on the roller could be washed by one washing with water. With regard to the water resistance of the film, ink elution from the cured ink film in water at 25? C. was not recognized even after 24 hours. The resistance to surface staining was excellent with the reflection density in the non-printing part of 0.1.

Comparative Example 1

[0196] The procedure of Example 1 was repeated except that resin I was replaced with resin VIII so that the resin had a weight average molecular weight of 29,000, an acid value of 282 mgKOH/g, and an iodine number of 0 mol/kg to evaluate the sensitivity, the washability with water, the water resistance of the film, and the resistance to surface staining. The printing ink prepared had the viscosity as high as 114 Pa.Math.s which was a level unsuitable for the lithography. With regard to the washability with water, all remaining ink on the roller could be washed by one washing with water. The resistance to surface staining was excellent with the reflection density in the non-printing part of 0.2. However, the sensitivity was insufficient with the belt conveyer speed of 75 m/min. The water resistance of the film was also insufficient, and ink elution from the cured ink film in water at 25? C. was recognized before 12 hours.

Comparative Example 2

[0197] The procedure of Example 1 was repeated except that resin I was replaced with resin IX so that the resin had a weight average molecular weight of 40,000, an acid value of 0 mgKOH/g, and an iodine number of 3.2 mol/kg to evaluate the sensitivity, the washability with water, the water resistance of the film, and the resistance to surface staining. The printing ink prepared had a viscosity as low as 9 Pa.Math.s unsuitable for the lithography. The sensitivity was excellent with the belt conveyer speed of 150 m/min. With regard to the water resistance of the film, ink elution from the cured ink film in water at 25? C. was not recognized even after 24 hours. However, washability with water was insufficient with the ink residue remaining on the roller even after 3 washings with water. The resistance to surface staining was insufficient with the reflection density in the non-printing part of 0.8.

Example 9

[0198] Components of the ink composition shown in Table 2-1 were weighed and mixed for dispersion by using a paint conditioner to thereby produce a printing ink.

[0199] The resulting ink was subjected to the flexography adaptability test to evaluate the sensitivity, the washability with water, and the water resistance of the film. The results are shown in Table 2-1.

[0200] The thus prepared printing ink had a suitable viscosity of 1420 mPa.Math.s. The sensitivity was excellent with the belt conveyer speed of 120 m/min. With regard to the washability with water, the ink on the printed material could be washed by one washing. With regard to the water resistance of the film, ink elution from the cured ink film in water at 25? C. was not recognized even after 24 hours.

Examples 10 and 11

[0201] The procedure of Example 9 was repeated except that the resin III or IV were used instead of the resin I and concentration of the ethylenically unsaturated group (iodine number) and concentration of the hydrophilic group (acid value) were as shown in Table 2-1 to evaluate the sensitivity, the washability with water, and the water resistance of the film. The sensitivity and the water resistance of the film tended to increase with increase in the concentration of the ethylenically unsaturated group and the washability with water tended to improve with the increase in the concentration of the hydrophilic group.

Comparative Example 3

[0202] The procedure of Example 9 was repeated except that the resin VIII was used instead of the resin I so that the resin had a weight average molecular weight of 29,000, an acid value of 282 mgKOH/g, and an iodine number of 0 mol/kg to evaluate the sensitivity, the washability with water, and the water resistance of the film. The ink prepared had a viscosity as high as 4090 mPa.Math.s, and the ink was unsuitable for use in flexography. With regard to the washability with water, the ink on the printed material could be washed by one washing. However, the sensitivity was insufficient with the belt conveyer speed of 40 m/min. With regard to the water resistance of the film, ink elution from the cured ink film in water at 25? C. was recognized before 12 hours.

Comparative Example 4

[0203] The procedure of Example 9 was repeated except that the resin IX was used instead of the resin I so that the resin had a weight average molecular weight of 40,000, an acid value of 0 mgKOH/g, and an iodine number of 3.2 mol/kg to evaluate the sensitivity, the washability with water, and the water resistance of the film. The ink prepared had a viscosity as low as 170 mPa.Math.s, and the ink was unsuitable for use in flexography. The sensitivity was excellent with the belt conveyer speed of 140 m/min. With regard to the water resistance of the film, ink elution from the cured ink film in water at 25? C. was not recognized even after 24 hours. However, with regard to the washability with water, ink residue was found after repetitive washing.

Example 12

[0204] The ink was prepared by repeating the procedure of Example 9 except that the ink composition used was the one shown in Table 2-1, and evaluation for adaptability to gravure printing was used instead of the evaluation for flexography to thereby evaluate sensitivity, washability with water, and the water resistance of the film. The printing ink prepared had a suitable viscosity of 570 mPa.Math.s. The sensitivity was excellent with the belt conveyer speed of 120 m/min. With regard to the washability with water, the ink on the printed material could be washed by one washing. With regard to the water resistance of the film, ink elution from the cured ink film in water at 25? C. was not recognized even after 24 hours.

Examples 13 and 14

[0205] The ink was prepared by repeating the procedure of Example 12 except that the ink composition used was the one shown in Table 2-1 and the ethylenically unsaturated group concentration (iodine number) and the hydrophilic group concentration (acid value) were as shown in Table 2-1 to evaluate the sensitivity, the washability with water, and water resistance of the film. The sensitivity and the water resistance of the film tended to increase with increase in the concentration of the ethylenically unsaturated group and the washability with water tended to improve with the increase in the concentration of the hydrophilic group.

Comparative Example 5

[0206] The procedure of Example 12 was repeated except that the ink composition used was the one shown in Table 2-2 so that the resin had a weight average molecular weight of 29,000, an acid value of 282 mgKOH/g, and an iodine number 0 mol/kg to evaluate the sensitivity, the washability with water, and the water resistance of the film. The ink prepared had a viscosity as high as 1280 mPa.Math.s, and the ink was unsuitable for use in gravure printing. With regard to the washability with water, the ink on the printed material could be washed by one washing. However, the sensitivity was insufficient with the belt conveyer speed of 50 m/min. With regard to the water resistance of the film, ink elution from the cured ink film in water at 25? C. was recognized before 12 hours.

Comparative Example 6

[0207] The procedure of Example 12 was repeated except that the ink composition used was the one shown in Table 2-2 so that the resin had a weight average molecular weight of 40,000, an acid value of 0 mgKOH/g, and an iodine number of 3.2 mol/kg to evaluate the sensitivity, the washability with water, and the water resistance of the film. The ink prepared had a viscosity as low as 41 mPa.Math.s, and the ink was unsuitable for use in gravure printing. The sensitivity was excellent with the belt conveyer speed of 140 m/min. With regard to the water resistance of the film, ink elution from the cured ink film in water at 25? C. was not recognized even after 24 hours. However, with regard to the washability with water, ink residue was found after repetitive washing.

Example 15

[0208] The ink was prepared by repeating the procedure of Example 9 except that the ink composition used was the one shown in Table 2-1, and evaluation for adaptability to inkjet printing was used instead of the evaluation for flexography to evaluate the sensitivity, the washability with water, and the water resistance of the film. The sensitivity was excellent with the belt conveyer speed of 120 m/min. With regard to the washability with water, the ink on the printed material could be washed by one washing. With regard to the water resistance of the film, ink elution from the cured ink film in water at 25? C. was not recognized even after 24 hours.

Examples 16 and 17

[0209] The ink was prepared by repeating the procedure of Example 15 except that the ink composition used was the one shown in Table 2-1 and the ethylenically unsaturated group concentration (iodine number) and the hydrophilic group concentration (acid value) were as shown in Table 2-1 to evaluate the sensitivity, the washability with water, and the water resistance of the film. The sensitivity and the water resistance of the film tended to increase with increase in the concentration of the ethylenically unsaturated group and the washability with water tended to improve with the increase in the concentration of the hydrophilic group.

Comparative Example 7

[0210] The procedure of Example 15 was repeated except that the ink composition used was the one shown in Table 2-2 so that the resin had a weight average molecular weight of 29,000, an acid value of 282 mgKOH/g, and an iodine number of 0 mol/kg to evaluate the sensitivity, the washability with water, and the water resistance of the film. The ink prepared had a viscosity as high as 235 mPa.Math.s, and the ink was unsuitable for use in inkjet printing. With regard to the washability with water, the ink on the printed material could be washed by one washing. However, the sensitivity was insufficient with the belt conveyer speed of 40 m/min. With regard to the water resistance of the film, ink elution from the cured ink film in water at 25? C. was recognized before 12 hours.

Comparative Example 8

[0211] The procedure of Example 15 was repeated except that the ink composition used was the one shown in Table 2-2 so that the resin had a weight average molecular weight of 40,000, an acid value of 0 mgKOH/g, and an iodine number of 3.2 mol/kg to evaluate the sensitivity, the washability with water, and the water resistance of the film. The ink prepared had a viscosity as low as 0.7 mPa.Math.s, and the ink was unsuitable for use in inkjet printing. The sensitivity was excellent with the belt conveyer speed of 130 m/min. With regard to the water resistance of the film, ink elution from the cured ink film in water at 25? C. was not recognized even after 24 hours. However, with regard to the washability with water, ink residue was found after repetitive washing.

[0212] The composition of the components used and the evaluation results of Examples and the Comparative Examples are shown in the following Tables.

TABLE-US-00001 TABLE 1 Comparative Example Example 1 2 3 4 5 6 7 8 1 2 Composition Seika cyanine blue 20 20 20 20 20 20 20 20 20 20 (Mass %) Resin I 12 12 Resin II 12 Resin III 12 Resin IV 12 Resin V 12 Resin VI 12 Resin VII 12 Resin VIII 12 Resin IX 12 Reactive diluent I 24 24 24 24 24 24 24 24 24 24 Reactive diluent II 33 33 33 33 33 33 33 29 33 33 Photopolymerization initiator I 5 5 5 5 5 5 5 5 5 5 Sensitizing agent I 5 5 5 5 5 5 5 5 5 5 Polymerization inhibitor I 1 1 1 1 1 1 1 1 1 1 Additive I 4 Evaluation Acid value (mgKOH/g) 102 10 35 62 190 240 259 102 282 0 Iodine value (mol/kg) 2.0 3.1 2.9 2.5 1.0 0.5 0.25 2.0 0.0 3.2 Sensitivity (m/min) 130 150 145 135 125 115 100 125 75 150 Washability with water (Washing method A) 3 2 2 2 3 3 3 3 3 1 Washability with water (Washing method B) 3 2 3 3 3 3 3 3 3 1 Water resistance of the resin 3 3 3 3 3 3 2 3 1 3 Resistance to surface staining 0.2 0.5 0.4 0.3 0.2 0.2 0.2 0.1 0.2 0.8 Viscosity (Pa .Math. s) 51 17 27 39 72 88 94 47 114 9

TABLE-US-00002 TABLE 2-1 Example 9 10 11 12 13 14 15 16 17 Composition Pigment I 10 10 10 10 10 10 7.5 7.5 7.5 (Mass %) Resin I 6 5 3 Resin III 6 5 3 Resin VII 6 5 3 Resin VIII Resin IX Reactive diluent I 20 20 20 14 14 14 10.5 10.5 10.5 Reactive diluent II 36 36 36 37 37 37 32 32 32 Water 20 20 20 27 27 27 37 37 37 Amine compound I 2 2 2 1 1 1 Photopolymerization initiator I 5 5 5 6 6 6 8 8 8 Sensitizing agent I 1 1 1 1 1 1 1 1 1 Polymerization inhibitor I 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Evaluation Acid value (mgKOH/g) 102 35 259 102 35 259 102 35 259 Iodine value (mol/kg) 2.0 2.9 0.25 2.0 2.9 0.25 2.0 2.9 0.25 Sensitivity (m/min) 120 140 80 120 130 80 120 130 70 Washability with water (Washing method B) 3 2 3 3 2 3 3 2 3 Water resistance of the resin 3 3 2 3 3 2 3 3 2 Viscosity (mPa .Math. s) 1420 460 2900 570 225 790 17 3 35

TABLE-US-00003 TABLE 2-2 Comparative Example 3 4 5 6 7 8 Composition Seika cyanine blue 10 10 10 10 7.5 7.5 (Mass %) Resin I Resin III Resin VII Resin VIII 6 5 3 Resin IX 6 5 3 Reactive diluent I 20 20 16 16 10.5 10.5 Reactive diluent II 36 36 37 37 32 32 water 20 20 27 27 37 37 Amine compound I 2 2 1 1 Photopolymerization initiator I 5 5 6 6 8 8 Sensitizing agent I 1 1 1 1 1 1 Polymerization inhibitor I 0.1 0.1 0.1 0.1 0.1 0.1 Evaluation Acid value (mgKOH/g) 282 0 282 0 282 0 Iodine value (mol/kg) 0.0 3.2 0.0 3.2 0.0 3.2 Sensitivity (m/min) 40 140 50 140 40 130 Washability with water 3 1 3 1 3 1 Water resistance of the resin 1 3 1 3 1 3 Viscosity (mPa .Math. s) 4090 170 1280 41 235 0.7

[0213] Polyfunctional (meth)acrylate 1: a mixture of pentaerythritol triacrylate and pentaerythritol tetraacrylate Miramer (Registered Trademark) M340 (manufactured by Miwon) having hydroxyl group; hydroxyl value, 115 mgKOH/g; molecular weight, 298

[0214] Polyfunctional (meth)acrylate 2: a mixture of pentaerythritol triacrylate and pentaerythritol tetraacrylate ARONIX (Registered Trademark) M-306 (manufactured by Toagosei Company, Limited) having hydroxyl group; hydroxyl value, 171 mgKOH/g; molecular weight, 298

[0215] Polyfunctional (meth)acrylate 3: a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate ARONIX (Registered Trademark) M-403 (manufactured by Toagosei Company, Limited) having hydroxyl group; hydroxyl value, 53 mgKOH/g; molecular weight, 524

[0216] Polyfunctional (meth)acrylate 4: a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate ARONIX (Registered Trademark) M-402 (manufactured by Toagosei Company, Limited) having hydroxyl group; hydroxyl value, 28 mgKOH/g; molecular weight, 524

[0217] Polyfunctional (meth)acrylate 5: glycerin dimethacrylate NK ester (Registered Trademark) 701 (manufactured by SHIN-NAKAMURA CHEMICAL CO., LTD.) having hydroxyl group; hydroxyl value, 240 mgKOH/g; molecular weight, 228

[0218] Polyfunctional (meth)acrylate 6: pentaerythritol tetraacrylate modified with ethylene oxide Miramer (Registered Trademark) M4004 (manufactured by Miwon) having no hydroxyl group; molecular weight, 571

[0219] Resin 1: 0.55 equivalent weight of glycidyl methacrylate was reacted (addition reaction) with the carboxyl group of a copolymer comprising 25 mass % of methyl methacrylate, 25 mass % of styrene, and 50 mass % of methacrylic acid to produce resin 1 having an ethylenically unsaturated group and a hydrophilic group. The resulting resin 1 had an weight average molecular weight of 34,000, an acid value of 105 mgKOH/g, and an iodine number of 2.0 mol/kg.

[0220] Resin 2: 0.5 equivalent weight of glycidyl methacrylate was reacted (addition reaction) with the carboxyl group of a copolymer comprising 25 mass % of methyl methacrylate, 25 mass % of styrene, and 50 mass % of methacrylic acid to produce resin 2 having an ethylenically unsaturated group and a hydrophilic group. The resulting resin 2 had a weight average molecular weight of 53,000, an acid value of 114 mgKOH/g, an iodine number of 1.8 mol/kg.

[0221] Resin 3: Resin 3 having a hydrophilic group comprising 25 mass % of methyl methacrylate, 25 mass % styrene, and 50 mass % of methacrylic acid was produced. The resulting resin 3 had a weight average molecular weight of 24,000 and an acid value of 210 mgKOH/g.

[0222] Resin 4: VS-1057 (manufactured by SEIKO PMC CORPORATION, acrylic resin having a hydrophilic group with a weight average molecular weight of 18000 and an acid value of 40 mgKOH/g)

[0223] Resin 5: Resin 5 having a hydrophilic group comprising 25 mass % of methyl methacrylate, 20 mass % of styrene, and 55 mass % of methacrylic acid was produced. The resulting resin 5 had a weight average molecular weight of 9,000 and an acid value of 262 mgKOH/g.

[0224] Resin 6: ISO-DAP (manufactured by Daiso Co., Ltd., diallyl phthalate resin having no hydrophilic group with a weight average molecular weight of 30,000 and acid value 0 mgKOH/g)

[0225] Polymerization inhibitor 1: p-methoxy phenol (manufactured by Wako Pure Chemical Industries, Ltd.)

[0226] The weight average molecular weight of the resin is the value measured by gel permeation chromatography (GPC) using tetrahydrofuran for the mobile phase. The column used was Shodex KF-803, and the weight average molecular weight was calculated in terms of polystyrene.

(1) Fluidity

[0227] Parallel plates (gap, 0.1 mm; diameter, 25 mm) were mounted on Rheometer-MCR301 manufactured by Anton Paar, and the loss tangent tan ? at 25? C., a strain of 1%, and an angular velocity of 1 rad/s was measured for 0.05 ml of varnish for lithographic ink measured by an ink pipette. The fluidity is good at the tan ? value of 3 to 5, better at 5 to 10, and very good at 10 or higher.

(2) Viscosity

[0228] Cylinder spindle No. 4 was mounted on Model B viscometer DV-II manufactured by BROOKFIELD, and viscosity at 25? C. and 0.5 rpm of the varnish for lithographic ink was measured. This viscosity is preferably 10 to 400 Pa.Math.s, more preferably 50 to 300 Pa.Math.s, and still more preferably 100 to 250 Pa.Math.s since both surface staining resistance and the fluidity of the lithographic ink are favorable in such range.

[0229] Pigment 1: Seika cyanine blue 4920 (manufactured by Dainichiseika Color & Chemicals Mfg. Co., Ltd.)

[0230] Photopolymerization initiator 1: IRGACURE (Registered Trademark) 907 (manufactured by BASF)

[0231] Photopolymerization initiator 2: IRGACURE (Registered Trademark) TPO-L (manufactured by BASF)

[0232] Sensitizing agent 1: diethylaminobenzophenone (manufactured by Tokyo Chemical Industry Co., Ltd.)

[0233] Additive 1: lauryl acrylate (manufactured by Wako Pure Chemical Industries, Ltd.)

[0234] Emulsifier 1: RHEODOL (Registered Trademark) Super-TW-L120 (manufactured by Kao Corporation) having a HLB value of 16.7

[0235] Wax 1: PTFE wax, KTL-4N (manufactured by KITAMURA LIMITED)

[0236] A waterless lithography plate (TAN-E manufactured by Toray Industries, Inc.) was mounted on an offset press (Oliver 266EPZ manufactured by SAKURAI GRAPHIC SYSTEMS CORPORATION), and 5000 coated papers were printed by using inks respectively having the composition of Examples 18 to 26, Reference Examples 1 to 3, and Comparative Examples 9 to 11. The ink was cured by UV irradiation using a UV irradiation apparatus manufactured by Ushio (120 W/cm, 1 ultra-high pressure metal halide lamp) at a belt conveyer speed of 80 m/min to obtain the printed material. The evaluation method was as described below.

[0237] A water lithography plate (XP-F manufactured by FUJIFILM Corporation) was mounted on an offset press (Oliver 266EPZ, manufactured by SAKURAI GRAPHIC SYSTEMS CORPORATION), and 5000 coated papers were printed with inks respectively having the composition of Examples 27 to 29, Reference Examples 4, and Comparative Examples 12 and 13 by using tap water admixed with 3 weight % [A1] [A2] of an etching solution (SOLAIA-505, manufactured by T&K TOKA) for the wetting water. The ink was cured by UV irradiation using a UV irradiation apparatus manufactured by Ushio (120 W/cm, 1 ultra-high pressure metal halide lamp) at a belt conveyer speed of 80 m/min to obtain the printed material.

(1) Viscosity

[0238] A cone plate (cone angle, 1; diameter, 40 mm) was mounted on Rheometer-MCR301 manufactured by Anton Paar, and the viscosity at 25? C. and 0.5 rpm was measured for 0.15 ml of the ink measured by an ink pipette.

(2) Surface Staining Concentration

[0239] Cyan density in the non-printing part of the printed material was evaluated for the case when the cyan density in the solid part of the printed material was 2.0 by using a reflection densitometer (SpectroEye manufactured by GretagMacbeth). The resistance to surface staining was inferior when the reflected density was in excess of 0.15, good when the reflected density was up to 0.10, and excellent when the reflected density was up to 0.05.

(3) Gloss

[0240] The ink cured film on the printed material was measured for its gross value by using a precision gloss meter GM-26D (manufactured by MURAKAMI COLOR RESEARCH LABORATORY). The gloss was evaluated good when the gloss value was at least 30 and excellent when the gloss value was at least 35.

[0241] Resin 1, polyfunctional (meth)acrylate 1, and polymerization inhibitor 1 were weighed in the ratio shown in Table 3. The resin 1 and the polymerization inhibitor 1 were added to the polyfunctional (meth)acrylate 1 at 90? C., and after dissolution by agitation, the varnish for lithographic ink 1 was obtained by cooling to room temperature.

[0242] The thus prepared varnish for lithographic ink 1 exhibited good fluidity with the tan ? of 3.2 and excellent viscosity of 154 Pa.Math.s.

[0243] Varnishes 2 to 5 were prepared by repeating the procedure of the varnish 1 except that the type of the polyfunctional (meth)acrylate having hydroxyl group was changed to polyfunctional (meth)acrylates 2 to 5 as shown in Table 3. The viscosity and the tan ? value of the varnish tended to increase with the increase in the hydroxyl value of the polyfunctional (meth)acrylate having hydroxyl group, while the viscosity of the varnish tended to increase and the tan ? value tended to decrease with the increase in the molecular weight of the polyfunctional (meth)acrylate having hydroxyl group.

[0244] The varnishes 6 to 8 were prepared by repeating the procedure of the varnish 1 except that the content of the polyfunctional (meth)acrylate having hydroxyl group 1 was changed as shown in Table 3. The viscosity of the varnish tended increase while the tan ? value tended to decrease with the increase in the content of the polyfunctional (meth)acrylate having hydroxyl group.

[0245] The varnishes 9 to 13 were prepared by repeating the procedure of the varnish 1 except that the type of the resins was changed to that of resins 2 to 6 as shown in Table 3. The viscosity and the tan ? value tended to increase with the increase in the acid value of the resin, and the viscosity of the varnish tended to increase with the increase in the molecular weight of the resin. In the case of the varnish 13 wherein the acid value of the resin was 0, the varnish viscosity was less than 10 Pa.Math.s.

TABLE-US-00004 TABLE 3 Var- nish Varnish Varnish Varnish Varnish Varnish Varnish Varnish Varnish Varnish Varnish Varnish Varnish 1 2 3 4 5 6 7 8 9 10 11 12 13 Com- Polyfunctional 64 78 33 18 64 64 64 64 64 position (meth)acrylate 1 (Mass Polyfunctional 64 %) (meth)acrylate 2 Polyfunctional 64 (meth)acrylate 3 Polyfunctional 64 (meth)acrylate 4 Polyfunctional 64 (meth)acrylate 5 Polyfunctional 14 14 14 14 14 45 60 14 14 14 14 14 (meth)acrylate 6 Resin 1 22 22 22 22 22 22 22 22 Resin 2 22 Resin 3 22 Resin 4 22 Resin 5 22 Resin 6 22 Polymerization 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 inhibitor 1 Eval- tan ? 3.2 3.4 1.8 1.5 2.7 2.6 3.1 8.1 3.0 3.4 6.0 8.9 41 uation Viscosity (Pa .Math. s) 154 254 291 378 268 231 94 37 334 277 41 47 9

[Example 18]<Preparation of Waterless Lithographic Ink>

[0246] The varnish 1, the pigment 1, the photopolymerization initiators 1 and 2, the sensitizing agent 1, the additive 1, and the wax 1 were weighed according to the composition shown in Table 4 and passed through roller gap 1 of a three roll mill EXAKT (Registered Trademark) M-80S (manufactured by EXAKT) twice at a speed of 500 rpm to obtain the lithographic ink.

[0247] The resulting ink was subjected to waterless lithography test to evaluate the performance. The results are shown in Table 4.

[0248] The resulting lithographic ink had a viscosity at 0.5 rpm of 58 Pa.Math.s. The reflected density in the non-printing part was 0.04, and the resistance to surface staining was excellent. The resulting printed material had an excellent gloss in the solid part of with the gloss value of 38.

[Examples 19 to 22]<Types of the Polyfunctional (Meth)Acrylate Having Hydroxyl Group>

[0249] The procedure of Example 18 was repeated except that the varnish 1 was changed to the composition of varnishes 2 to 5 in Table 4 to prepare the lithographic inks of Examples 19 to 22. There was tendency that increase in the hydroxyl value and the molecular weight of the polyfunctional (meth)acrylate having hydroxyl group constituting the varnishes 2 to 5 resulted in the increase of the ink viscosity and the loss of resistance to surface staining. In the meanwhile, such increase in the hydroxyl value and the molecular weight also tended to result in the loss of the gloss value in the solid part of the printed material.

[Examples 23 to 25]<Content of the Polyfunctional (Meth)Acrylate Having Hydroxyl Group>

[0250] The procedure of Example 18 was repeated except that the composition of the varnish 1 was changed to the one shown in varnishes 6 to 8 of Table 4 to prepare the lithographic inks of Examples 23 to 25. There was tendency that the resulting lithographic ink had higher viscosity and improved resistance to the surface staining with the increase in the content of the polyfunctional (meth)acrylate having hydroxyl group constituting the varnish 6 to 8. In the meanwhile, such increase in the content also tended to result in the loss of the gloss value in the solid part of the printed material.

[Example 26, Reference Examples 1 to 3 and Comparative Example 9]<Type of the Resin Having a Hydrophilic Group>

[0251] The procedure of Example 18 was repeated except that the varnish 1 was changed to the varnishes 9 to 13 according to the composition of Table 4 to prepare the lithographic inks of Example 26, Reference Examples 1 to 3, and Comparative Example 9. The resulting lithographic inks tended to exhibit higher viscosity and improved resistance to surface staining with the increase in the acid value and the molecular weight of the resin constituting the varnish 9 to 13. However, gloss in the solid part of the printed material was inferior. In particular, the viscosity was low and the resistance to surface staining was insufficient in the case of the resin of Comparative Example 9 having no acidic group.

TABLE-US-00005 TABLE 4 Reference Comparative Example Example Example 18 19 20 21 22 23 24 25 26 1 2 3 9 Composition Varnish 1 60 (Mass %) Varnish 2 60 Varnish 3 60 Varnish 4 60 Varnish 5 60 Varnish 6 60 Varnish 7 60 Varnish 8 60 Varnish 9 60 Varnish 10 60 Varnish 11 60 Varnish 12 60 Varnish 13 60 Pigment 1 18 18 18 18 18 18 18 18 18 18 18 18 18 Photopolymerization 6 6 6 6 6 6 6 6 6 6 6 6 6 initiator 1 Photopolymerization 4 4 4 4 4 4 4 4 4 4 4 4 4 initiator 2 Sensitizing agent 1 4 4 4 4 4 4 4 4 4 4 4 4 4 Additive 1 6 6 6 6 6 6 6 6 6 6 6 6 6 Wax 1 2 2 2 2 2 2 2 2 2 2 2 2 2 Evaluation Viscosity @ 0.5 rpm 58 74 93 120 84 80 46 31 99 79 33 37 20 (Pa .Math. s) Resistance to surface 0.04 0.02 0.01 <0.01 0.04 0.05 0.1 0.15 <0.01 0.04 0.14 0.11 0.39 staining Gloss 38 34 30 28 31 33 40 42 30 33 42 41 42

[Example 27]<Preparation of the Water Lithographic Ink>

[0252] The procedure of Example 18 was repeated except that the composition was as shown in Table 5 and the emulsifier 1 was added to prepare the lithographic ink of Example 27. The resulting lithographic ink had a viscosity at 0.5 rpm of 66 Pa.Math.s. The resistance to surface staining was excellent with the reflection density in the non-printing area of 0.02. The resulting printed material had an excellent gloss in the solid part of 36.

[Examples 28 to 29, Reference Example 4, and Comparative Example 10]<Preparation of Water Lithographic Inks with Different Varnish>

[0253] The lithographic inks of Examples 28 to 29, Reference Example 4, and Comparative Example 10 were prepared by repeating the procedure of Example 27 except that the composition of the varnish was changed to the one shown in Table 5. The resulting lithographic ink experienced decrease in the resistance to surface staining due to increase in the acid value of the resin constituting the varnish and resulting difficulty of taking in the wetting water (Reference Example 4). In the meanwhile, the resistance to surface staining was improved due to the decrease in the hydroxyl value of the polyfunctional (meth)acrylate having hydroxyl group constituting the varnish and the resulting adequate hydrophobicity of the ink (Examples 28 and 29). The ink of Comparative Example 10 exhibited low viscosity and insufficient resistance to surface staining.

TABLE-US-00006 TABLE 5 Reference Comparative Example Example Example 27 28 29 4 10 Composition Varnish 1 66 (Mass %) Varnish 4 66 Varnish 8 66 Varnish 10 66 Varnish 13 66 Pigment 1 18 18 18 18 18 Photopolymerization initiator 1 6 6 6 6 6 Photopolymerization initiator 2 4 4 4 4 4 Sensitizing agent 1 4 4 4 4 4 Emulsifier 1 0.2 0.2 0.2 0.2 0.2 Wax 1 2 2 2 2 2 Evaluation Viscosity @0.5 rpm (Pa .Math. s) 66 121 83 40 29 Resistance to surface staining 0.02 0.01 0.03 0.15 0.19 Gloss 36 30 34 39 39

[0254] Pigment A: (azo lake pigment) Lake Red (Registered Trademark) C #405(F) (manufactured by Dainichiseika Color & Chemicals Mfg. Co., Ltd.)

[0255] Pigment B: (azo lake pigment) SEIKAFAST (Registered Trademark) CARMINE 1476T-7 (manufactured by Dainichiseika Color & Chemicals Mfg. Co., Ltd.)

[0256] Pigment C: (azo lake pigment) 430 BRILLIANT BORDEAU 10B (manufactured by Dainichiseika Color & Chemicals Mfg. Co., Ltd.)

[0257] Pigment D: (azo lake pigment) LIONOL (Registered Trademark) RED TT-4801G (manufactured by TOYO INK)

[0258] Pigment E: (copper phthalocyanine complex) CHROMOFINE (Registered Trademark) ?-type BLUE PB-15:3 (manufactured by Dainichiseika Color & Chemicals Mfg. Co., Ltd.)

[0259] Pigment F: (copper phthalocyanine complex) CHROMOFINE (Registered Trademark) GREEN PG-7 (manufactured by Dainichiseika Color & Chemicals Mfg. Co., Ltd.)

[0260] Pigment G: (cobalt phthalocyanine complex) CHROMOFINE (Registered Trademark) cobalt phthalocyanine BLUE PB-75 (manufactured by Dainichiseika Color & Chemicals Mfg. Co., Ltd.)

[0261] Pigment H: carbon black MA8 (manufactured by Mitsubishi Chemical Corporation); particle diameter, 24 nm; dibutyl phthalate absorption number, 57 cm.sup.3/100 g; having an acidic group (carboxyl group)

[0262] Pigment I: carbon black MA77 (manufactured by Mitsubishi Chemical Corporation); particle diameter, 23 nm; dibutyl phthalate absorption number, 68 cm.sup.3/100 g; having an acidic group (carboxyl group)

[0263] Pigment J: carbon black MA11 (manufactured by Mitsubishi Chemical Corporation); particle diameter, 29 nm; dibutyl phthalate absorption number, 64 cm.sup.3/100 g; having an acidic group (carboxyl group)

[0264] Pigment K: carbon black MA14 (manufactured by Mitsubishi Chemical Corporation); particle diameter, 40 nm; dibutyl phthalate absorption number, 73 cm.sup.3/100 g; having an acidic group (carboxyl group)

[0265] Pigment L: carbon black MA100 (manufactured by Mitsubishi Chemical Corporation); particle diameter, 24 nm; dibutyl phthalate absorption number, 100 cm.sup.3/100 g; having an acidic group (carboxyl group)

[0266] Pigment M: carbon black MA220 (manufactured by Mitsubishi Chemical Corporation); particle diameter, 55 nm; dibutyl phthalate absorption number, 93 cm.sup.3/100 g; having an acidic group (carboxyl group)

[0267] Pigment N: carbon black #45 (manufactured by Mitsubishi Chemical Corporation); particle diameter, 24 nm; dibutyl phthalate absorption number, 53 cm.sup.3/100 g; having no acidic group

[0268] Pigment dispersant A: DISPERBYK (Registered Trademark)-111; acid value, 129 mgKOH/g; phosphate group-containing anionic surfactant (manufactured by BYK Japan KK)

[0269] Pigment dispersant B: PLYSURF (Registered Trademark) A212C; acid value, 110 mgKOH/g; phosphate group-containing anionic surfactant (manufactured by DKS Co. Ltd.)

[0270] Pigment dispersant C: DISPARON (Registered Trademark) 1850; acid value, 73 mgKOH/g; phosphate group-containing anionic surfactant (manufactured by Kusumoto Chemicals, Ltd.)

[0271] Pigment dispersant D: PLYSURF (Registered Trademark) A208N; acid value, 145 mgKOH/g; phosphate group-containing anionic surfactant (manufactured by DKS Co. Ltd.)

[0272] Pigment dispersant E: PLYSURF (Registered Trademark) A219B; acid value, 51 mgKOH/g; phosphate group-containing anionic surfactant (manufactured by DKS Co. Ltd.)

[0273] Pigment dispersant F: DISPERBYK (Registered Trademark)-2015; acid value, 10 mgKOH/g (manufactured by BYK Japan KK)

[0274] Pigment dispersant G: PLYSURF (Registered Trademark) A208F; acid value, 180 mgKOH/g; phosphate group-containing anionic surfactant (manufactured by DKS Co. Ltd.)

[0275] Pigment dispersant H: DISPERBYK (Registered Trademark)-2155; acid value, 0 mgKOH/g (manufactured by BYK Japan KK)

[0276] Pigment dispersant I: DISPARON (Registered Trademark) DA-325; amine value, 20 mgKOH/g (manufactured by Kusumoto Chemicals, Ltd.)

[0277] Pigment dispersant J: BYK (Registered Trademark)-9076; amine value, 44 mgKOH/g 1 (manufactured by BYK Japan KK)

[0278] Pigment dispersant K: DISPERBYK (Registered Trademark)-191; amine value, 20 mgKOH/g (manufactured by BYK Japan KK)

[0279] Pigment dispersant L: DISPERBYK (Registered Trademark)-2155; amine value, 48 mgKOH/g (manufactured by BYK Japan KK)

[0280] Pigment dispersant M: DISPERBYK (Registered Trademark)-2022; amine value, 61 mgKOH/g (manufactured by BYK Japan KK)

[0281] Pigment dispersant N: DISPERBYK (Registered Trademark)-2000; amine value, 4 mgKOH/g (manufactured by BYK Japan KK)

[0282] Resin A (containing an ethylenically unsaturated group and a hydrophilic group (acidic group)): 0.6 equivalent weight of glycidyl methacrylate was reacted (addition reaction) with the carboxyl group of a copolymer comprising 25 mass % of methyl methacrylate, 25 mass % of styrene, and 50 mass % of methacrylic acid (by dissolving methyl methacrylate, styrene, methacrylic acid, and azoisobutyronitrile, slowly adding these dissolved reactants dropwise to a solvent maintained at 75? C., allowing the reaction to proceed for 5 hours; and in the meanwhile, dissolving glycidyl methacrylate, tetrabutylammonium chloride, and p-methoxy phenol, and slowly adding dropwise these dissolved reactants to the reaction system, and allowing the reaction to proceed for 3 hours). The resin had a weight average molecular weight of 34,000, an acid value of 102 mgKOH/g, and an iodine number of 2.0 mol/kg.

[0283] Resin B (containing an ethylenically unsaturated group and a hydrophilic group (acidic group)): 0.95 equivalent weight of glycidyl methacrylate was reacted (addition reaction) with the carboxyl group of a copolymer comprising 25 mass % of methyl methacrylate, 25 mass % of styrene, and 50 mass % of methacrylic acid. The resin had a weight average molecular weight of 39,000, an acid value of 10 mgKOH/g, and an iodine number of 3.1 mol/kg.

[0284] Resin C (containing an ethylenically unsaturated group and a hydrophilic group (acidic group)): 0.9 equivalent weight of glycidyl methacrylate was reacted (addition reaction) with the carboxyl group of a copolymer comprising 25 mass % of methyl methacrylate, 25 mass % of styrene, and 50 mass % of methacrylic acid. The resin had a weight average molecular weight of 38,000, an acid value of 35 mgKOH/g, and an iodine number of 2.9 mol/kg.

[0285] Resin D (an ethylenically unsaturated group and a hydrophilic group (acidic group)): 0.8 equivalent weight of glycidyl methacrylate was reacted (addition reaction) with the carboxyl group of a copolymer comprising 25 mass % of methyl methacrylate, 25 mass % of styrene, and 50 mass % of methacrylic acid. The resin had a weight average molecular weight of 37,000, an acid value of 62 mgKOH/g, and an iodine number of 2.5 mol/kg.

[0286] Resin E (containing an ethylenically unsaturated group and a hydrophilic group (acidic group)): 0.4 equivalent weight of glycidyl methacrylate was reacted (addition reaction) with the carboxyl group of a copolymer comprising 25 mass % of methyl methacrylate, 25 mass % of styrene, and 50 mass % of methacrylic acid. The resin had a weight average molecular weight of 32,000, an acid value of 190 mgKOH/g, and an iodine number of 1.0 mol/kg.

[0287] Resin F (containing an ethylenically unsaturated group and a hydrophilic group (acidic group)): 0.2 equivalent weight of glycidyl methacrylate was reacted (addition reaction) with the carboxyl group of a copolymer comprising 25 mass % of methyl methacrylate, 25 mass % of styrene, and 50 mass % of methacrylic acid. The resin had a weight average molecular weight of 31,000, an acid value of 240 mgKOH/g, and an iodine number of 0.5 mol/kg.

[0288] Resin G (containing an ethylenically unsaturated group and a hydrophilic group (acidic group)): 0.1 equivalent weight of glycidyl methacrylate was reacted (addition reaction) with the carboxyl group of a copolymer comprising 25 mass % of methyl methacrylate, 25 mass % of styrene, and 50 mass % of methacrylic acid. The resin had a weight average molecular weight of 30,000, an acid value of 259 mgKOH/g, and an iodine number of 0.25 mol/kg.

[0289] Resin H (containing only the hydrophilic group (acidic group)): a copolymer comprising 25 mass % of methyl acrylate, 25 mass % of styrene, and 50 mass % of methacrylic acid having a weight average molecular weight of 29,000, an acid value of 282 mgKOH/g, and an iodine number of 0 mol/kg.

[0290] Resin I (containing only the ethylenically unsaturated group): 1.0 equivalent weight of glycidyl methacrylate was reacted (addition reaction) with the carboxyl group of a copolymer comprising 25 mass of methyl methacrylate, 25 mass % of styrene, and 50 mass % of methacrylic acid. The resin had a weight average molecular weight of 40,000, an acid value of 0 mgKOH/g, and an iodine number of 3.2 mol/kg.

[0291] Reactive diluent A (containing an ethylenically unsaturated group and a hydrophilic group): Miramer (Registered Trademark) M340 pentaerythritol triacrylate (manufactured by Miwon)

[0292] Reactive diluent B (containing only ethylenically unsaturated group): Miramer (Registered Trademark) M280 polyethylene glycol diacrylate (manufactured by Miwon)

[0293] Reactive diluent C (containing only ethylenically unsaturated group): Miramer (Registered Trademark) M300 trimethylolpropanetriacrylate (manufactured by Miwon)

[0294] Photopolymerization initiator A: IRGACURE (Registered Trademark) 907 (manufactured by BASF)

[0295] Sensitizing agent A: diethylaminobenzophenone (manufactured by Tokyo Chemical Industry Co., Ltd.)

[0296] Polymerization inhibitor A: hydroquinone monomethyl ether (manufactured by Tokyo Chemical Industry Co., Ltd.)

[0297] Additive A: lauryl acrylate (manufactured by Wako Pure Chemical Industries, Ltd.)

[0298] Parallel plates (diameter, 25 mm; gap, 0.1 mm) were mounted on Rheometer-MCR301 manufactured by Anton Paar, and loss elastic modulus (viscosity) and storage elastic modulus (elastic modulus) at 25? C., an angular velocity of 100 rad/s, and a strain of up to 1% were measured to calculate the value of the loss tangent tan ? represented by the ratio of the loss modulus to the storage modulus. The fluidity was recognized at the tan ? value of I or higher, and evaluated good at 2.0 or higher and very good at 3.0 or higher.

[0299] A waterless lithography plate (TAN-E manufactured by Toray Industries, Inc.) was mounted on an offset press (Oliver 266EPZ manufactured by SAKURAI GRAPHIC SYSTEMS CORPORATION), and 10000 coated papers were printed by using inks respectively having the composition shown in Tables 6 to 14 to evaluate the lithography adaptability and the printed material. The methods used for the evaluation were as described above.

(1) Sensitivity

[0300] The printed material was irradiated with UV by using a UV irradiation apparatus manufactured by Ushio (120 W/cm, 1 ultra-high metal halide lamp) under the condition of the belt conveyer speed of 0 to 150 m/min to determine the belt conveyer speed when the ink on the printed material became sufficiently cured such that the ink was no longer peelable when a cellophane adhesive tape (Sellotape (Registered Trademark) No. 405) was adhered onto the coated paper and then peeled from the coated paper. In this case, higher belt conveyer speed indicates higher sensitivity since the curing can be accomplished with reduced exposure. The sensitivity was evaluated insufficient when the belt conveyer speed was less than 100 m/min; good when the belt conveyer speed was at least 100 m/min and less than 120 m/min; and excellent when the belt conveyer speed was at least 120 m/min since the printed material having such sensitivity can be used in a power-saving UV printer.

(2) Washability with Water

[0301] The ink remaining on the roller of the printer after finishing the printing was washed with 1 liter of water flowing over the printer, and the washability of the ink with water was evaluated by 3 grades. [0302] A: the ink was entirely removed by washing once with water [0303] B: the ink was entirely removed by washing twice with water [0304] C: the ink residue remained even after washing three times with water
(3) Water resistance of the film

[0305] The ink cured film on the printed material was retained in water at 25? C., and the water resistance was evaluated by 3 grades. Elution of the ink into the water was visually confirmed. [0306] A: no ink elution was observed before 24 hours [0307] B: no ink elution was observed before 12 hours, but the ink was partly eluted within 24 hours. [0308] C: ink elution was observed before 12 hours.

(4) Gloss

[0309] The ink cured film on the printed material was measured for its gross value by using a precision gloss meter GM-26D (manufactured by MURAKAMI COLOR RESEARCH LABORATORY) at a measurement angle of 60?. The gloss was evaluated poor when the gloss value was less than 30, and good when the gloss value was at least 30, and excellent when the gloss value was at least 35.

(5) Resistance to Surface Staining

[0310] Magenta density in the non-printing part of the printed material was evaluated for the case when the magenta density in the solid part of the printed material was 2.0 by using a reflection densitometer (SpectroEye manufactured by GretagMacbeth). The resistance to surface staining was inferior when the reflected density was in excess of 0.5, slightly inferior when the reflected density was in excess of 0.3, good when the reflected density was up to 0.3, and excellent when the reflected density was up to 0.1.

Example 30

[0311] Components of the ink composition shown in Table 6 were weighed and passed through gap (10 ?m) of a three roll mill EXAKT (Registered Trademark) M-80S (manufactured by EXAKT) three times to obtain the lithographic ink.

[0312] The resulting lithographic ink was evaluated by the fluidity test and the printing test as described above to evaluate the ink fluidity, the sensitivity, the washability with water, the gloss, and the resistance to the surface staining. The results are shown in Table 6.

[0313] The lithographic ink prepared had an excellent fluidity with the value of the loss tangent tan ? of 3.67. The sensitivity was excellent with the belt conveyer speed of 130 m/min. With regard to the washability with water, all remaining ink on the roller could be washed by one washing with water, and with regard to the water resistance, no ink elution was recognized before 24 hours. The gloss was excellent with the value of 40. The resistance to surface staining was excellent with the reflection density in the non-printing area of 0.05.

[Examples 31 to 36]<Type of the Pigment>

[0314] The procedure of Example 30 was repeated except that the type of the pigment was as shown in Table 6 to conduct the fluidity test and evaluation of the sensitivity, the washability with water, the water resistance, the gloss, and the resistance to surface staining. The lithographic inks of all of Examples 31 to 36 exhibited excellent results in the fluidity test and evaluation of the sensitivity, the washability with water, the water resistance, the gloss, and the resistance to surface staining.

[Examples 37 to 42]<Type of the Pigment Dispersant>

[0315] The procedure of Example 30 was repeated except that the type of the pigment dispersant was changed as shown in Table 7 to conduct the fluidity test and evaluation of the sensitivity, the washability with water, the water resistance, the gloss, and the resistance to surface staining. The lithographic inks of all of Examples 37 to 42 exhibited good results in the fluidity test and evaluation of the sensitivity, the washability with water, the water resistance, the gloss, and the resistance to surface staining. However, the ink fluidity and the gloss were particularly excellent in Examples 37 and 39 wherein the acid value of the pigment dispersant was respectively 110 mgKOH/g and 145 mgKOH/g. For the Examples 41 and 42 wherein the pigment dispersant had an acid value of 10 mgKOH/g and 180 mgKOH/g, the ink fluidity was relatively low, and accordingly, the ink exhibited good gloss.

[Examples 43 to 47]<Content of the Pigment Dispersant>

[0316] The procedure of Example 30 was repeated except that the content of the pigment dispersant was changed as shown in Table 8 to conduct the fluidity test and evaluation of the sensitivity, the washability with water, the water resistance, the gloss, and the resistance to surface staining. For all lithographic inks of Examples 43 to 47, the results for the fluidity test, the sensitivity, the washability with water, the water resistance, and the resistance to the surface staining were generally favorable. However, for Example 45 wherein content of the pigment dispersant in relation to the pigment was 30%, the results of fluidity test and gloss evaluation were excellent, and for Examples 46 and 471 wherein content of the pigment dispersant in relation to the pigment was respectively 3% and 60%, the ink fluidity was relatively low and the ink exhibited good gloss.

[Examples 48 to 53]<Type of the Resin>

[0317] The procedure of Example 30 was repeated except that the type of the resin was as shown in Table 9 to conduct the fluidity test and evaluation of the sensitivity, the washability with water, the water resistance, the gloss, and the resistance to surface staining. In Example 48 wherein the resin had an acid value of 10 mgKOH/g, the ink fluidity was relatively low and the ink exhibited good gloss while the low acid value of the resin resulted in the washability with water of B and slightly poor resistance to surface staining. In Example 53 wherein the resin had an iodine number of 0.25 mol/kg, the ink exhibited low curability despite its good sensitivity, and the water resistance was B. The lithographic ink of Examples 49 to 52 exhibited excellent results in the fluidity test and evaluation of the sensitivity, the washability with water, the water resistance, the gloss, and the resistance to surface staining.

Example 54

[0318] The procedure of Example 30 was repeated except that the type of the pigment dispersant was changed as shown in Table 10 to conduct the fluidity test and evaluation of the sensitivity, the washability with water, the water resistance, the gloss, and the resistance to surface staining. The resulting ink had a reduced fluidity with the loss tangent tan ? in the fluidity measurement of 0.95. While the sensitivity, the washability with water, the water resistance, and the resistance to the surface staining were excellent, the gloss was insufficient with the greatly reduced gloss value of 24.

Example 55

[0319] The procedure of Example 30 was repeated except that the content of the pigment dispersant was changed as shown in Table 10 to conduct the fluidity test and evaluation of the sensitivity, the washability with water, the water resistance, the gloss, and the resistance to surface staining. The resulting ink had a reduced fluidity with the loss tangent tan ? in the fluidity measurement of 0.88. While the sensitivity, the washability with water, the water resistance, and the resistance to the surface staining were excellent, the gloss was insufficient with the greatly reduced gloss value of 21.

Comparative Example 11

[0320] The procedure of Example 30 was repeated except that the type of the reactive diluent and the content of the pigment dispersant were changed as shown in Table 10 to conduct the fluidity test and evaluation of the sensitivity, the washability with water, the water resistance, the gloss, and the resistance to surface staining. While the resulting ink exhibited good washability with water and good resistance to surface staining, the fluidity was poor with the loss tangent tan ? in the fluidity measurement of 0.84. Also, the ink had insufficient sensitivity with the belt conveyer speed of 75 m/min. In addition, the water resistance was C with the ink elution at 6 hours in the measurement of the water resistance. The gloss was also insufficient with the greatly reduced gloss value of 19.

Comparative Example 12

[0321] The procedure of Example 30 was repeated except that the type of the resin and the reactive diluent were as shown in Table 10 to conduct the fluidity test and evaluation of the sensitivity, the washability with water, the water resistance, the gloss, and the resistance to surface staining. The resulting ink had a reduced fluidity with the loss tangent tan ? in the fluidity measurement of 1.24. While the sensitivity was good, the washability with water was C with the residue remaining even after washing three times with water. The gloss was poor with the gloss value of 27. The resistance to surface staining was poor with the reflected density in the non-printing part of 0.75.

TABLE-US-00007 TABLE 6 Example 30 Example 31 Example 32 Example 33 Example 34 Example 35 Example 36 Pigment Type Pigment A Pigment B Pigment C Pigment D Pigment E Pigment F Pigment G Mass % 15 15 15 15 15 15 15 Pigment dispersant Type Pigment Pigment Pigment Pigment Pigment Pigment Pigment dispersant A dispersant A dispersant A dispersant A dispersant A dispersant A dispersant A Mass % 3 3 3 3 3 3 3 Resin Type Resin A Resin A Resin A Resin A Resin A Resin A Resin A Mass % 12 12 12 12 12 12 12 Reactive diluent Type Reactive Reactive Reactive Reactive Reactive Reactive Reactive diluent A diluent A diluent A diluent A diluent A diluent A diluent A Mass % 60 60 60 60 60 60 60 Photopolymerization Mass % 3 3 3 3 3 3 3 initiator A Sensitizing agent A Mass % 3 3 3 3 3 3 3 Polymerization inhibitor A Mass % 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Additive A Mass % 3.9 3.9 3.9 3.9 3.9 3.9 3.9 Ink fluidity Loss tangent 3.67 3.32 3.75 3.49 3.55 3.07 3.12 Sensitivity (m/min) 130 125 135 130 130 135 130 Washability with water A A A A A A A Water resistance A A A A A A A Gloss Gloss value 40 40 41 40 40 41 40 Resistance to surface staining 0.05 0.1 0.08 0.09 0.07 0.08 0.1

TABLE-US-00008 TABLE 7 Example 37 Example 38 Example 39 Example 40 Example 41 Example 42 Pigment Type Pigment A Pigment A Pigment A Pigment A Pigment A Pigment A Mass % 15 15 15 15 15 15 Pigment dispersant Type Pigment Pigment Pigment Pigment Pigment Pigment dispersant B dispersant C dispersant D dispersant E dispersant F dispersant G Mass % 3 3 3 3 3 3 Resin Type Resin A Resin A Resin A Resin A Resin A Resin A Mass % 12 12 12 12 12 12 Reactive diluent Type Reactive Reactive Reactive Reactive Reactive Reactive diluent A diluent A diluent A diluent A diluent A diluent A Mass % 60 60 60 60 60 60 Photopolymerization initiator A Mass % 3 3 3 3 3 3 Sensitizing agent A Mass % 3 3 3 3 3 3 Polymerization inhibitor A Mass % 0.1 0.1 0.1 0.1 0.1 0.1 Additive A Mass % 3.9 3.9 3.9 3.9 3.9 3.9 Ink fluidity Loss tangent 3.51 2.45 3.34 2.21 1.87 1.82 Sensitivity (m/min) 125 130 135 135 130 125 Washability with water A A A A A A Water resistance A A A A A A Gloss Gloss value 41 36 40 35 34 33 Resistance to surface staining 0.04 0.07 0.06 0.09 0.14 0.13

TABLE-US-00009 TABLE 8 Example 43 Example 44 Example 45 Example 46 Example 47 Pigment Type Pigment A Pigment A Pigment A Pigment A Pigment A Mass % 15 15 15 15 15 Pigment dispersant Type Pigment Pigment Pigment Pigment dispersant A Pigment dispersant A dispersant A dispersant A dispersant A Mass % 0.75 7.50 4.50 0.45 9.00 Resin Type Resin A Resin A Resin A Resin A Resin A Mass % 3 3 3 3 3 Reactive diluent Type Reactive Reactive Reactive Reactive diluent A Reactive diluent A diluent A diluent A diluent A Mass % 12 12 12 12 12 Photopolymerization initiator A Mass % 3 3 3 3 3 Sensitizing agent A Mass % 3 3 3 3 3 Polymerization inhibitor A Mass % 0.1 0.1 0.1 0.1 0.1 Additive A Mass % 3.9 3.9 3.9 3.9 3.9 Ink fluidity Loss tangent 2.34 2.11 3.45 1.81 1.75 Sensitivity (m/min) 135 120 125 135 120 Washability with water A A A A A Water resistance A A A A A Gloss Gloss value 36 35 40 33 32 Resistance to surface staining 0.07 0.15 0.1 0.08 0.18

TABLE-US-00010 TABLE 9 Example 48 Example 49 Example 50 Example 51 Example 52 Example 53 Pigment Type Pigment A Pigment A Pigment A Pigment A Pigment A Pigment A Mass % 15 15 15 15 15 15 Pigment dispersant Type Pigment Pigment Pigment Pigment Pigment Pigment dispersant A dispersant A dispersant A dispersant A dispersant A dispersant A Mass % 3 3 3 3 3 3 Resin Type Resin B Resin C Resin D Resin E Resin F Resin G Mass % 12 12 12 12 12 12 Reactive Type Reactive Reactive Reactive Reactive Reactive Reactive diluent A diluent diluent A diluent A diluent A diluent A diluent A Mass % 60 60 60 60 60 60 Photopolymerization Mass % 3 3 3 3 3 3 initiator A Sensitizing agent A Mass % 3 3 3 3 3 3 Polymerization inhibitor A Mass % 0.1 0.1 0.1 0.1 0.1 0.1 Additive A Mass % 3.9 3.9 3.9 3.9 3.9 3.9 Ink fluidity Loss tangent 2.75 3.02 3.32 3.87 3.95 3.98 Sensitivity (m/min) 145 140 135 125 120 115 Washability with water B A A A A A Water resistance A A A A A B Gloss Gloss value 33 35 38 40 42 43 Resistance to surface staining 0.36 0.19 0.1 0.09 0.08 0.07

TABLE-US-00011 TABLE 10 Example 54 Example 55 Comparative Example 11 Comparative Example 12 Pigment Type Pigment A Pigment A Pigment A Pigment A Mass % 15 15 15 15 Pigment dispersant Type Pigment Pigment dispersant A Pigment dispersant A Pigment dispersant A dispersant H Mass % 3 0 0 3 Resin Type Resin A Resin A Resin H Resin I Mass % 12 12 12 12 Reactive diluent Type Reactive Reactive diluent A Reactive diluent B Reactive diluent C diluent A Mass % 60 60 60 60 Photopolymerization initiator A Type 3 3 3 3 Sensitizing agent A Mass % 3 3 3 3 Polymerization inhibitor A Type 0.1 0.1 0.1 0.1 Additive A Mass % 3.9 3.9 3.9 3.9 Ink fluidity Loss tangent 0.95 0.88 0.84 1.24 Sensitivity (m/min) 125 135 75 130 Washability with water A A A C Water resistance A A C A Gloss Gloss value 24 21 19 27 Resistance to surface staining 0.11 0.09 0.08 0.75

Example 56

[0322] Components of the ink composition shown in Table 11 were weighed and passed through gap (10 ?m) of a three roll mill EXAKT (Registered Trademark) M-80S (manufactured by EXAKT) three times to obtain the lithographic ink.

[0323] The resulting lithographic ink was evaluated by the fluidity test and the printing test as described above to evaluate the ink fluidity, the sensitivity, the washability with water, the water resistance, the gloss, and the resistance to the surface staining. The results are shown in Table 11.

[0324] The lithographic ink prepared had an excellent fluidity with the value of the loss tangent tan ? of 3.27. The sensitivity was excellent with the belt conveyer speed of 130 m/min. With regard to the washability with water, all remaining ink on the roller could be washed by one washing with water, and with regard to the water resistance, no ink elution was recognized before 24 hours. The gloss was excellent with the gloss value of 42. The resistance to surface staining was excellent with the reflection density in the non-printing area of 0.05.

[Examples 57 to 61]<Type of the Pigment>

[0325] The procedure of Example 56 was repeated except that the type of the pigment was as shown in Table 11 to conduct the fluidity test and evaluation of the sensitivity, the washability with water, the water resistance, the gloss, and the resistance to surface staining. In the Examples 60 and 61 wherein the dibutyl phthalate absorption number of the carbon black was respectively 100 and 93, the gloss was good due to the relative increase in the surface roughness of the printed material. The lithographic ink of all of Examples 57 to 59 exhibited excellent results in the fluidity test and evaluation of the sensitivity, the washability with water, the water resistance, the gloss, and the resistance to surface staining.

[Examples 62 to 67]<Type of the Resin>

[0326] The procedure of Example 56 was repeated except that the type of the resin was as shown in Table 12 to conduct the fluidity test and evaluation of the sensitivity, the washability with water, the water resistance, the gloss, and the resistance to surface staining. For Example 62 wherein the resin B had an acid value of 10 mgKOH/g, the ink fluidity was relatively low and the ink had a good gloss. In addition, due to the low acid value of the resin, the washability with water was B and the resistance to surface staining was slightly poor. For Example 67 wherein the resin G had an iodine number of 0.25 mol/kg, the ink showed poor curability despite good sensitivity, and the water resistance was B. Examples 63 to 66 generally exhibited excellent results for the fluidity test, the sensitivity, the washability with water, the water resistance, the gloss, and the resistance to surface staining.

[Examples 68 to 72]<Type of the Pigment Dispersant>

[0327] The procedure of Example 56 was repeated except that the type of the pigment dispersant was as shown in Table 13 to conduct the fluidity test and evaluation of the sensitivity, the washability with water, the water resistance, the gloss, and the resistance to surface staining. For Examples 71 and 72 wherein the amine value of the pigment dispersant was respectively 61 mgKOH/g and 4 mgKOH/g, ink fluidity was relatively low and the ink exhibited good gloss. For the lithographic inks of Examples 68 to 70, good results were generally obtained for the fluidity test, the sensitivity, the washability with water, the water resistance, the gloss, and the resistance to surface staining.

Example 73

[0328] The procedure of Example 56 was repeated except that the type of the pigment was as shown in Table 14 to conduct the fluidity test and evaluation of the sensitivity, the washability with water, the water resistance, the gloss, and the resistance to surface staining. The resulting ink had a reduced fluidity with the loss tangent tan ? in the fluidity measurement of 0.95. While the sensitivity, the washability with water, the water resistance, and the resistance to the surface staining were excellent, the gloss was insufficient with the greatly reduced gloss value of 24.

Comparative Example 13

[0329] The procedure of Example 56 was repeated except that the type of the resin was as shown in Table 14 to conduct the fluidity test and evaluation of the sensitivity, the washability with water, the water resistance, the gloss, and the resistance to surface staining. While the resulting ink exhibited good fluidity test results as well as high washability with water and good resistance to surface staining, the ink had insufficient sensitivity with the belt conveyer speed of 75 m/min. In addition, the water resistance was C with the ink elution at 6 hours in the measurement of the water resistance.

Comparative Example 14

[0330] The procedure of Example 56 was repeated except that the type of the resin was as shown in Table 14 to conduct the fluidity test and evaluation of the sensitivity, the washability with water, the water resistance, the gloss, and the resistance to surface staining. The resulting ink had a reduced fluidity with the loss tangent tan ? in the fluidity measurement of 1.24. Although the sensitivity and the water resistance were good, the washability with water was C with the ink residue remaining even after washing three times with water. The gloss was poor with the gloss value of 27. The resistance to surface staining was poor with the reflected density in the non-printing part of 0.75.

TABLE-US-00012 TABLE 11 Example 56 Example 57 Example 58 Example 59 Example 60 Example 61 Pigment Type Pigment H Pigment I Pigment J Pigment K Pigment L Pigment M Mass % 15 15 15 15 15 15 Resin Type Resin A Resin A Resin A Resin A Resin A Resin A Mass % 12 12 12 12 12 12 Pigment dispersant Type Pigment Pigment Pigment Pigment Pigment Pigment dispersant I dispersant I dispersant I dispersant I dispersant I dispersant I Mass % 3 3 3 3 3 3 Reactive diluent Type Reactive Reactive Reactive Reactive Reactive Reactive diluent A diluent A diluent A diluent A diluent A diluent A Mass % 60 60 60 60 60 60 Photopolymerization initiator A Mass % 3 3 3 3 3 3 Sensitizing agent A Mass % 3 3 3 3 3 3 Polymerization inhibitor A Mass % 0.1 0.1 0.1 0.1 0.1 0.1 Additive A Mass % 3.9 3.9 3.9 3.9 3.9 3.9 Ink fluidity Loss 3.27 3.75 3.51 3.99 3.84 4.15 tangent Sensitivity (m/min) 130 130 135 130 130 135 Washability with water A A A A A A Water resistance A A A A A A Gloss Gloss 42 37 38 35 30 31 value Resistance to surface staining 0.05 0.1 0.08 0.09 0.07 0.08

TABLE-US-00013 TABLE 12 Example 62 Example 63 Example 64 Example 65 Example 66 Example 67 Pigment Type Pigment H Pigment H Pigment H Pigment H Pigment H Pigment H Mass % 15 15 15 15 15 15 Resin Type Resin B Resin C Resin D Resin E Resin F Resin G Mass % 12 12 12 12 12 12 Pigment dispersant Type Pigment Pigment Pigment Pigment Pigment Pigment dispersant I dispersant I dispersant I dispersant I dispersant I dispersant I Mass % 3 3 3 3 3 3 Reactive diluent Type Reactive Reactive Reactive Reactive Reactive Reactive diluent A diluent A diluent A diluent A diluent A diluent A Mass % 60 60 60 60 60 60 Photopolymerization initiator A Mass % 3 3 3 3 3 3 Sensitizer A Mass % 3 3 3 3 3 3 Polymerization inhibitor A Mass % 0.1 0.1 0.1 0.1 0.1 0.1 Additive A Mass % 3.9 3.9 3.9 3.9 3.9 3.9 Ink fluidity Loss 2.7 3.12 3.41 3.33 3.44 3.47 tangent Sensitivity (m/min) 145 140 135 125 120 115 Washability with water B A A A A A Water resistance A A A A A B Gloss Gloss value 33 35 38 40 42 43 Resistance to surface staining 0.32 0.18 0.1 0.09 0.08 0.07

TABLE-US-00014 TABLE 13 Example 68 Example 69 Example 70 Example 71 Example 72 Pigment Type Pigment H Pigment H Pigment H Pigment H Pigment H Mass % 15 15 15 15 15 Resin Type Resin A Resin A Resin A Resin A Resin A Mass % 12 12 12 12 12 Pigment dispersant Type Pigment Pigment Pigment Pigment Pigment dispersant J dispersant K dispersant L dispersant M dispersant N Mass % 3 3 3 3 3 Reactive diluent Type Reactive Reactive Reactive Reactive Reactive diluent A diluent A diluent A diluent A diluent A Mass % 60 60 60 60 60 Photopolymerization Mass % 3 3 3 3 3 initiator A Sensitizing agent A Mass % 3 3 3 3 3 Polymerization inhibitor A Mass % 0.1 0.1 0.1 0.1 0.1 Additive A Parts by weight 3.9 3.9 3.9 3.9 3.9 Ink fluidity Loss tangent 3.19 3.34 3.08 2.51 2.78 Sensitivity (m/min) 135 130 135 135 135 Washability with water A A A A A Water resistance A A A A A Gloss Gloss value 41 36 40 33 34 Resistance to surface staining 0.04 0.07 0.06 0.09 0.14

TABLE-US-00015 TABLE 14 Comparative Comparative Example 73 Example 13 Example 14 Pigment Type Pigment N Pigment H Pigment H Mass % 15 15 15 Resin Type Resin A Resin H Resin I Mass % 12 12 12 Pigment Type Pigment Pigment Pigment dispersant dispersant I dispersant I dispersant I Mass % 3 3 3 Reactive Type Reactive Reactive Reactive diluent diluent A diluent A diluent A Mass % 60 60 60 Photo- Mass % 3 3 3 polymerization initiator A Sensitizing Mass % 3 3 3 agent A Polymerization Mass % 0.1 0.1 0.1 inhibitor A Additive A Mass % 3.9 3.9 3.9 Ink fluidity Loss tangent 0.95 3.45 1.24 Sensitivity 125 75 130 Washability with water A A C Water resistance A C A Gloss Gloss value 24 42 27 Resistance to 0.11 0.08 0.75 surface staining

Example 74

[0331] The lithography adaptability test and the curing test as described below were conducted by using a lithographic ink shown in Table 1 with the same composition as that of the Example 1 to evaluate the sensitivity, the water resistance of the film, and the warping of the substrate.

[0332] A waterless lithography plate (TAN-E manufactured by Toray Industries, Inc.) was mounted on an offset press (Oliver 266EPZ manufactured by SAKURAI GRAPHIC SYSTEMS CORPORATION), and 10000 coated papers were printed by using inks respectively having the composition shown in Example 1 to evaluate the lithography adaptability and the printed material.

[0333] The printed material was irradiated with UV by using a UV irradiation apparatus manufactured by Ushio (120 W/cm, 1 ultra-high metal halide lamp) under the condition of the belt conveyer speed of 0 to 150 m/min to determine the belt conveyer speed when the ink on the printed material becomes sufficiently cured such that the ink is no longer peelable when a cellophane adhesive tape (Sellotape (Registered Trademark) No. 405) is adhered onto the polyethylene terephthalate film and then peeled from the polyethylene terephthalate film. In this case, higher belt conveyer speed indicates higher sensitivity since the curing can be accomplished with reduced exposure. The sensitivity was evaluated insufficient when the belt conveyer speed was less than 100 m/min, good when the belt conveyer speed was at least 100 m/min and less than 120 m/min, and excellent when the belt conveyer speed was at least 120 m/min.

[0334] The sensitivity was excellent with the belt conveyer speed of 130 m/min. With regard to the water resistance of the film, ink elution from the cured ink film in water at 25? C. was not recognized even after 24 hours. However, warping by thermal expansion and contraction was visually recognizable for the terephthalate film after the UV irradiation.

Example 75

[0335] The procedure of Example 74 was repeated except that the UV irradiation apparatus manufactured by Ushio (120 W/cm, 1 ultra-high metal halide lamp) was replaced with an UV irradiation apparatus (5 W/cm.sup.2, LED-UV) manufactured by Panasonic Industrial Devices SUNX Co., Ltd. to conduct the lithography adaptability test and the curing test to thereby evaluate the sensitivity, the water resistance of the film, and the warping of the substrate.

[0336] The sensitivity was excellent with the belt conveyer speed of 120 m/min. With regard to the water resistance of the film, ink elution from the cured ink film in water at 25? C. was not recognized even after 24 hours. In addition, warping by thermal expansion and contraction was not recognizable for the polyethylene terephthalate film after the LED-UV irradiation.

Example 76

[0337] The procedure of Example 74 was repeated except that the polyethylene terephthalate film was replaced with an aluminum-deposited paper and the UV irradiation apparatus manufactured by Ushio (120 W/cm, 1 ultra-high metal halide lamp) was replaced with an electron beam irradiation apparatus Min-EB (100 eV) manufactured by Ushio to conduct the lithography adaptability test and the curing test to thereby evaluate the sensitivity, the water resistance of the film, and the warping of the substrate.

[0338] The sensitivity was excellent with the belt conveyer speed of 130 m/min. With regard to the water resistance of the film, ink elution from the cured ink film in water at 25? C. was not recognized even after 24 hours. In addition, warping by thermal expansion and contraction was not recognizable in the aluminum-deposited paper after irradiation with the electron beam.

LITHOGRAPHIC PRINTING INK, VARNISH FOR LITHOGRAPHIC INKS, AND METHOD FOR PRODUCING PRINTED MATTER USING SAID INK

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Cpc classification

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C09D11/106

CHEMISTRY; METALLURGY

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C09D11/03

CHEMISTRY; METALLURGY

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C09D11/037

CHEMISTRY; METALLURGY

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C09D11/107

CHEMISTRY; METALLURGY

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C09D11/101

CHEMISTRY; METALLURGY

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B41M1/08

PERFORMING OPERATIONS; TRANSPORTING

International classification

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C09D11/101

CHEMISTRY; METALLURGY

Classification Explorer

B41M1/08

PERFORMING OPERATIONS; TRANSPORTING

Classification Explorer

C09D11/107

CHEMISTRY; METALLURGY

Classification Explorer

C09D11/03

CHEMISTRY; METALLURGY

Classification Explorer

C09D11/037

CHEMISTRY; METALLURGY

Abstract

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