Flexographic printing ink for cigarette packaging paper and preparation method of flexographic printing ink

Abstract

The invention relates to flexographic printing ink for cigarette wrapping paper and a preparation method of the flexographic printing ink, and the flexographic printing ink comprises the following components in parts by weight: 45-65 parts of urethane acrylate, 15-30 parts of 1, 3-propanediol, 1-3 parts of a curing agent, 1-3 parts of a defoaming agent and 1-3 parts The invention relates to a light-cured acrylic resin, which is prepared from the following components in parts by weight: 10 to 20 parts of 1, 6-hexanediol diacrylate, 10 to 20 parts of 2-phenoxyethyl acrylate, 8 to 16 parts of lauric acid methacrylate, 5 to 20 parts of filling modifier, 0.1 to 10 parts of pigment, 0.1 to 1 part of dispersing agent, 0.1 to 1 part of defoaming agent and 3.1 to 6.2 parts of photoinitiator. The UV flexible ink prepared by the invention not only has excellent glossiness, but also has higher surface hardness, wear resistance and adhesive force than the traditional UV ink, and is very suitable for printing on high-end cigarette packaging paper.

Description

Technical Field

[0001] The invention relates to the field of inks, and in particular to a flexographic ink for cigarette packaging paper and a preparation method thereof. Background Art

[0002] Cigarette wrapping paper is a special type of paper that wraps cigarettes and provides visual effects. The printing effect of cigarette wrapping paper can have a direct visual impact on consumers, making the product more likely to gain consumer favor. The outer packaging of cigarette paper is usually printed using flexible printing, which has almost no pollution during its production process. In addition, printing, plate making and process management are more environmentally friendly than other printing methods. Therefore, flexible printing is currently widely accepted as a green printing method worldwide. Flexible inks mainly include water-based flexible inks, solvent-based flexible inks, UV flexible inks, and flexible varnishes that are glazed by flexible printing.

[0003] UV ink is an environmentally friendly ink that has developed rapidly in recent years. It has quickly occupied the cigarette packaging paper market with its instant curing, no volatile solvents, and simple and convenient application. UV ink includes special packaging inks such as UV frosting, UV ice flower, UV foaming, UV wrinkle, UV embossing, UV refraction, UV gem, UV light fixation ink, UV varnish, etc. Although UV ink has a high gloss, the film layer formed after curing has defects such as insufficient wear resistance and corrosion resistance. These performance deficiencies have limited the application of UV ink in the field of cigarette packaging paper. Summary of the invention

[0004] In view of the problems existing in the prior art, the object of the present invention is to provide a flexographic ink for cigarette packaging paper and a preparation method thereof.

[0005] The purpose of the present invention is achieved by the following technical solutions:

[0006] In a first aspect, the present invention provides a flexographic ink for cigarette packaging paper, which comprises the following components calculated by weight:

[0007] 45-65 parts of polyurethane acrylate, 15-30 parts of 1,6-hexanediol diacrylate, 10-20 parts of 2-phenoxyethyl acrylate, 8-16 parts of lauric acid methacrylate, 5-20 parts of filler modifier, 0.1-10 parts of pigment, 0.1-1 parts of dispersant, 0.1-1 parts of defoamer and 3.1-6.2 parts of photoinitiator.

[0008] Preferably, the grade of the polyurethane acrylate (PUA) is one of UV-1205, UV-1230 and UV-1990.

[0009] Preferably, the filling modifier is a product obtained by first combining aminated allophane nanotubes with allyl glycidyl ether to obtain modified allophane nanotubes, and then reacting and combining with 2-mercaptobenzothiazole.

[0010] Preferably, the pigment is an organic pigment, including at least one of phthalocyanine red, phthalocyanine blue, phthalocyanine green, permanent yellow and permanent violet.

[0011] Preferably, the dispersant is at least one of TEGO-655, TEGO-688, TEGO-685, and TEGO-755W.

[0012] Preferably, the defoaming agent is at least one of BYK-012, BYK-085, BYK-1794 and BYK-024.

[0013] Preferably, the photoinitiator is at least one of hydroxycyclohexane phenone (photoinitiator 184), ethyl 2,4,6-trimethylbenzoylphenylphosphonate (photoinitiator TPO-L), and 2-hydroxy-2-methyl-1-phenyl-1-propanone (photoinitiator 1173).

[0014] Preferably, the preparation method of the filling modifier comprises the following steps:

[0015] S1, mixing hydrous allophane nanotubes with anhydrous ethanol, adding 3-aminopropyltriethoxysilane, and then reflux at 50-70°C for 3-10 hours. After the treatment is completed, centrifuge to collect the precipitate, and then rinse the precipitate with anhydrous ethanol three times, and place it in a vacuum box to dry, so as to obtain amination hydrous allophane nanotubes;

[0016] S2, adding allyl glycidyl ether to toluene, stirring and dissolving evenly, then adding amination-modified allophane nanotubes, dispersing evenly at room temperature, and then placing in a 60-70°C water bath and stirring at a speed of 150-250r / min for 5-10h. After the reaction is completed, removing the solvent under reduced pressure, washing with anhydrous ethanol three times, and then placing in a vacuum oven for drying to obtain modified allophane nanotubes;

[0017] S3. Add 2-mercaptobenzothiazole to chloroform, stir until evenly dissolved, then add modified allophane nanotubes, stir evenly at room temperature, and then use nitrogen as a protective gas, under the conditions of ultraviolet light and photoinitiator, stir the reaction for 1-2 hours. After the reaction is completed, remove the solvent under reduced pressure, wash three times with anhydrous ethanol, and place in a vacuum oven for drying to obtain a filling modifier.

[0018] Preferably, the particle size of the allophane nanotubes is 100±10 nm, the SiO2 content is greater than 28%, the Al2O3 content is greater than 56%, and the density is 1.86-1.88 g / cm 3 , purchased from Shandong Qiying Nanotechnology Co., Ltd.

[0019] In the S1, the mass volume ratio of the allophane nanotubes, 3-aminopropyltriethoxysilane and anhydrous ethanol is 1 g: (0.3-0.6) g: (15-35) mL.

[0020] Preferably, in S2, the mass volume ratio of amination-hydrated allophane nanotubes, allyl glycidyl ether and toluene is (1.1-1.5) g: (0.22-0.44) g: (20-40) mL.

[0021] Preferably, in S3, the mass volume ratio of the modified allophane nanotubes, 2-mercaptobenzothiazole and chloroform is (1.2-1.8) g: (0.34-0.68) g: (30-50) mL.

[0022] Preferably, in S3, the irradiation intensity of the ultraviolet light is 1.2-2.4 mW / cm 2 The photoinitiator is benzoin dimethyl ether or benzoin diethyl ether, and the added mass is 3%-8% of the mass of the modified allophane nanotubes.

[0023] In a second aspect, the present invention provides a method for preparing flexographic ink for cigarette packaging paper, comprising the following steps:

[0024] (1) firstly mix the weighed polyurethane acrylate, 1,6-hexanediol diacrylate, 2-phenoxyethyl acrylate, and lauric acid methacrylate, and stir evenly to obtain a first mixed solution;

[0025] (2) adding the weighed filler modifier, pigment, dispersant, and defoamer to the first mixed solution in sequence, and grinding and sieving to obtain a second mixed solution;

[0026] (3) Finally, the weighed photoinitiator is added to the second mixed solution, and stirred again to obtain flexographic ink for cigarette packaging paper.

[0027] The beneficial effects of the present invention are:

[0028] 1. The present invention prepares a UV flexible ink, which not only has excellent glossiness, but also has higher surface hardness, tinting power and adhesion than traditional UV ink, and is very suitable for printing on high-end cigarette packaging paper.

[0029] 2. The UV flexible ink prepared by the present invention uses acrylate as the main raw material, including polyurethane acrylate, 1,6-hexanediol diacrylate, 2-phenoxyethyl acrylate, and lauric acid methacrylate specially selected by the present invention. The ink obtained by compounding the four different types of acrylates can achieve the advantages of fast drying, good gloss, no pollution, and high printing quality.

[0030] 3. The filler modifier used in the present invention is used as both a filler and a modifier, and is prepared by combining amino-alophane nanotubes with allyl glycidyl ether to obtain modified allophane nanotubes, and then reacting and combining with 2-mercaptobenzothiazole to obtain a product. The filler modifier prepared by the present invention is applied to UV flexible ink, and the surface hardness, coloring and corrosion resistance of the ink are greatly improved.

[0031] 4. The 2-mercaptobenzothiazole used in the preparation of the filling modifier is a kind of rubber accelerator. The benzothiazole group is generally composed of a benzene ring and a thiazole ring, has high stability, and is not prone to oxidation-reduction reactions. The present invention introduces it into the filling modifier through a mercapto-double bond, thereby giving the filling modifier better stability and corrosion resistance. In addition, it is found through testing that the surface hardness and tinting power of the ink are also improved to a certain extent. DETAILED DESCRIPTION

[0032] The technical solution of the present invention is described below through specific examples. It should be understood that the one or more method steps mentioned in the present invention do not exclude the existence of other method steps before and after the combination step or the insertion of other method steps between these explicitly mentioned steps; it should also be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. Moreover, unless otherwise specified, the numbering of each method step is only a convenient tool for identifying each method step, and is not intended to limit the order of arrangement of each method step or to limit the scope of the present invention. The change or adjustment of the relative relationship thereof shall also be regarded as the scope of the present invention without substantially changing the technical content.

[0033] In order to better understand the above technical scheme, the exemplary embodiments of the present invention are described in more detail below. Although exemplary embodiments of the present invention are shown, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present invention and to enable the scope of the present invention to be fully communicated to those skilled in the art.

[0034] The parameters of the allophane used in the present invention are: the particle size of the allophane nanotubes is 100±10nm, the SiO2 content is greater than 28%, the Al2O3 content is greater than 56%, and the density is 1.86-1.88g / cm3 , purchased from Shandong Qiying Nanotechnology Co., Ltd.

[0035] The present invention will be further described below in conjunction with the following examples.

[0036] Example 1

[0037] A flexographic printing ink for cigarette packaging paper, comprising the following components, calculated by weight:

[0038] 55 parts of polyurethane acrylate, 21 parts of 1,6-hexanediol diacrylate, 15 parts of 2-phenoxyethyl acrylate, 12 parts of lauric acid methacrylate, 12 parts of filler modifier, 2.7 parts of pigment, 0.6 parts of dispersant, 0.6 parts of defoamer and 4.6 parts of photoinitiator.

[0039] Among them, the brand of polyurethane acrylate (PUA) is UV-1205; the pigment is phthalocyanine red; the dispersant is TEGO-655; the defoamer is BYK-012; and the photoinitiator is hydroxycyclohexane phenone (photoinitiator 184).

[0040] The preparation method of the filling modifier comprises the following steps:

[0041] S1. Take 1 g of allophane nanotubes and mix them with 25 mL of anhydrous ethanol, add 0.4 g of 3-aminopropyltriethoxysilane, and then reflux at 60° C. for 7 h. After the treatment, collect the precipitate by centrifugation in a centrifuge, then rinse the precipitate with anhydrous ethanol three times, and place it in a vacuum box to dry, thereby obtaining the amination allophane nanotubes;

[0042] S2, add 0.33g of allyl glycidyl ether to 30mL of toluene, stir and dissolve evenly, then add 1.3g of amination-modified allophane nanotubes, disperse evenly at room temperature, then place in a 65°C water bath and stir at a speed of 200r / min for 7h. After the reaction is completed, remove the solvent under reduced pressure, rinse with anhydrous ethanol three times, and then place in a vacuum oven for drying to obtain modified allophane nanotubes;

[0043] S3, add 0.51g 2-mercaptobenzothiazole to 40mL chloroform, stir until evenly dissolved, then add 1.5g modified allophane nanotubes, stir evenly at room temperature, then use nitrogen as protective gas, add 5% of the weight of modified allophane nanotubes of benzoin dimethyl ether as initiator, stir and react under ultraviolet light, the irradiation intensity of ultraviolet light is 1.8mW / cm 2 The stirring reaction time is 1.5h. After the reaction is completed, the solvent is removed under reduced pressure, washed three times with anhydrous ethanol, and placed in a vacuum box for drying to obtain a filling modifier.

[0044] The method for preparing the flexographic ink for cigarette packaging paper comprises the following steps:

[0045] (1) firstly mix the weighed polyurethane acrylate, 1,6-hexanediol diacrylate, 2-phenoxyethyl acrylate, and lauric acid methacrylate, and stir evenly to obtain a first mixed solution;

[0046] (2) adding the weighed filler modifier, pigment, dispersant, and defoamer to the first mixed solution in sequence, and grinding and sieving to obtain a second mixed solution;

[0047] (3) Finally, the weighed photoinitiator is added to the second mixed solution, and stirred again to obtain flexographic ink for cigarette packaging paper.

[0048] Example 2

[0049] A flexographic printing ink for cigarette packaging paper, comprising the following components, calculated by weight:

[0050] 45 parts of polyurethane acrylate, 15 parts of 1,6-hexanediol diacrylate, 10 parts of 2-phenoxyethyl acrylate, 8 parts of lauric acid methacrylate, 5 parts of filler modifier, 1.8 parts of pigment, 0.2 parts of dispersant, 0.3 parts of defoamer and 3.1 parts of photoinitiator.

[0051] Among them, the brand of polyurethane acrylate (PUA) is UV-1230; the pigment is phthalocyanine blue; the dispersant is TEGO-688; the defoamer is BYK-085; and the photoinitiator is ethyl 2,4,6-trimethylbenzoylphenylphosphonate (photoinitiator TPO-L).

[0052] The preparation method of the filling modifier comprises the following steps:

[0053] S1. Take 1 g of allophane nanotubes and mix them with 15 mL of anhydrous ethanol, add 0.3 g of 3-aminopropyltriethoxysilane, and then reflux at 50° C. for 3 h. After the treatment, collect the precipitate by centrifugation in a centrifuge, and then rinse the precipitate three times with anhydrous ethanol and place it in a vacuum box to dry, thereby obtaining the amination allophane nanotubes;

[0054] S2, add 0.22g of allyl glycidyl ether to 20mL of toluene, stir and dissolve evenly, then add 1.1g of amination-modified allophane nanotubes, disperse evenly at room temperature, then place in a 60°C water bath and stir at a speed of 150r / min for 5h. After the reaction is completed, remove the solvent under reduced pressure, rinse with anhydrous ethanol three times, and then place in a vacuum oven for drying to obtain modified allophane nanotubes;

[0055] S3, add 0.34g 2-mercaptobenzothiazole to 30mL chloroform, stir until evenly dissolved, then add 1.2g modified allophane nanotubes, stir evenly at room temperature, then use nitrogen as protective gas, add 3% of the mass of the modified allophane nanotubes as initiator benzoin dimethyl ether, stir and react for 1h under ultraviolet light, the irradiation intensity of ultraviolet light is 1.2mW / cm 2 After the reaction is completed, the solvent is removed under reduced pressure, washed three times with anhydrous ethanol, and placed in a vacuum box for drying to obtain a filling modifier.

[0056] The method for preparing the flexographic ink for cigarette packaging paper comprises the following steps:

[0057] (1) firstly mix the weighed polyurethane acrylate, 1,6-hexanediol diacrylate, 2-phenoxyethyl acrylate, and lauric acid methacrylate, and stir evenly to obtain a first mixed solution;

[0058] (2) adding the weighed filler modifier, pigment, dispersant, and defoamer to the first mixed solution in sequence, and grinding and sieving to obtain a second mixed solution;

[0059] (3) Finally, the weighed photoinitiator is added to the second mixed solution, and stirred again to obtain flexographic ink for cigarette packaging paper.

[0060] Example 3

[0061] A flexographic printing ink for cigarette packaging paper, comprising the following components, calculated by weight:

[0062] 65 parts of polyurethane acrylate, 30 parts of 1,6-hexanediol diacrylate, 20 parts of 2-phenoxyethyl acrylate, 16 parts of lauric acid methacrylate, 20 parts of filler modifier, 5.8 parts of pigment, 0.8 parts of dispersant, 0.9 parts of defoamer and 6.2 parts of photoinitiator.

[0063] Among them, the brand of polyurethane acrylate (PUA) is UV-1990; the pigment is phthalocyanine green; the dispersant is TEGO-755W; the defoamer is BYK-024; and the photoinitiator is 2-hydroxy-2-methyl-1-phenyl-1-propanone (photoinitiator 1173).

[0064] The preparation method of the filling modifier comprises the following steps:

[0065] S1. Take 1 g of allophane nanotubes and mix them with 35 mL of anhydrous ethanol, add 0.6 g of 3-aminopropyltriethoxysilane, and then reflux at 70° C. for 10 h. After the treatment, collect the precipitate by centrifugation in a centrifuge, then rinse the precipitate three times with anhydrous ethanol, and place it in a vacuum box to dry, thereby obtaining the amination allophane nanotubes;

[0066] S2, add 0.44g of allyl glycidyl ether to 40mL of toluene, stir and dissolve evenly, then add 1.5g of amination-modified allophane nanotubes, disperse evenly at room temperature, then place in a 70°C water bath and stir at a speed of 250r / min for 10h. After the reaction is completed, remove the solvent under reduced pressure, rinse with anhydrous ethanol three times, and then place in a vacuum oven for drying to obtain modified allophane nanotubes;

[0067] S3, add 0.68g 2-mercaptobenzothiazole to 50mL chloroform, stir until evenly dissolved, then add 1.8g modified allophane nanotubes, stir evenly at room temperature, then use nitrogen as protective gas, add 8% of the mass of the modified allophane nanotubes as initiator benzoin diethyl ether, stir and react for 2h under ultraviolet light, the irradiation intensity of ultraviolet light is 2.4mW / cm 2 After the reaction is completed, the solvent is removed under reduced pressure, washed three times with anhydrous ethanol, and placed in a vacuum box for drying to obtain a filling modifier.

[0068] The method for preparing the flexographic ink for cigarette packaging paper comprises the following steps:

[0069] (1) firstly mix the weighed polyurethane acrylate, 1,6-hexanediol diacrylate, 2-phenoxyethyl acrylate, and lauric acid methacrylate, and stir evenly to obtain a first mixed solution;

[0070] (2) adding the weighed filler modifier, pigment, dispersant, and defoamer to the first mixed solution in sequence, and grinding and sieving to obtain a second mixed solution;

[0071] (3) Finally, the weighed photoinitiator is added to the second mixed solution, and stirred again to obtain flexographic ink for cigarette packaging paper.

[0072] Comparative Example 1

[0073] A flexographic ink for cigarette packaging paper, which differs from Example 1 in that the filler modifier is replaced by allophane nanotubes, and other components and preparation methods are the same as those of Example 1.

[0074] Comparative Example 2

[0075] A flexographic ink for cigarette packaging paper, which differs from Example 1 in that the filler modifier is replaced by amination of allophane nanotubes, and other components and preparation methods are the same as those of Example 1.

[0076] Comparative Example 3

[0077] A flexographic ink for cigarette packaging paper, which differs from Example 1 in that the filler modifier is replaced by a mixture of allophane nanotubes and 2-mercaptobenzothiazole, the mass ratio of allophane nanotubes to 2-mercaptobenzothiazole is 1.5:0.51 g, and other ingredients and preparation methods are the same as those in Example 1.

[0078] Experimental testing

[0079] The UV ink prepared in Example 1 and Comparative Examples 1-3 was coated on the surface of the substrate by flexographic printing, and then placed under 800 mW / cm 2 The ink was dried under ultraviolet light at 45°C for 5 seconds. The performance of the dried and cured UV ink was tested accordingly.

[0080] The test items include: tinting power, adhesion, surface hardness and corrosion resistance; the tinting power test reference standard GB / T14624.2-2008; the adhesion test reference standard GB / T 9286-1998; the surface hardness test reference standard GB / T6739-2006; the acid resistance is to soak in a hydrochloric acid solution with a mass concentration of 5% for 24 hours, take out and dry to observe whether the ink has faded, fallen off or cracked (severity: large > small > slight > no abnormality); the alkali resistance is to soak in a sodium hydroxide solution with a mass concentration of 1% for 24 hours, take out and dry to observe whether the ink has faded, fallen off or cracked (severity: large > small > slight > no abnormality); the test results are shown in Table 1:

[0081] Table 1 Ink testing results

[0082]

[0083] As can be seen from Table 1 above, the flexographic ink prepared in Example 1 of the present invention not only has strong tinting power, but also has good adhesion and good acid and alkali resistance, indicating that its color fixing ability is also strong; in addition, it also has a high surface hardness, indicating that its wear resistance is good. In summary, the flexographic ink prepared in Example 1 has better comprehensive performance than traditional UV inks and is very suitable for printing on high-end cigarette packaging paper.

[0084] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms should not be understood as necessarily being directed to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification.

[0085] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A flexographic printing ink for cigarette packaging paper, characterized in that: Calculated by weight, it includes the following ingredients: 45-65 parts of polyurethane acrylate, 15-30 parts of 1,6-hexanediol diacrylate, 10-20 parts of 2-phenoxyethyl acrylate, 8-16 parts of lauric acid methacrylate, 5-20 parts of filler modifier, 0.1-10 parts of pigment, 0.1-1 parts of dispersant, 0.1-1 parts of defoamer and 3.1-6.2 parts of photoinitiator; The filling modifier is a product obtained by first combining amination of allophane nanotubes with allyl glycidyl ether to obtain modified allophane nanotubes, and then reacting and combining with 2-mercaptobenzothiazole.

2. The flexographic ink for cigarette packaging paper according to claim 1, characterized in that: The polyurethane acrylate has a grade of UV-1205, UV-1230, and UV-1990.

3. The flexographic ink for cigarette packaging paper according to claim 1, characterized in that: The pigment is an organic pigment, including at least one of phthalocyanine red, phthalocyanine blue, phthalocyanine green, permanent yellow and permanent violet.

4. The flexographic ink for cigarette packaging paper according to claim 1, characterized in that: The dispersant is at least one of TEGO-655, TEGO-688, TEGO-685, and TEGO-755W.

5. The flexographic ink for cigarette packaging paper according to claim 1, characterized in that: The defoaming agent is at least one of BYK-012, BYK-085, BYK-1794 and BYK-024.

6. The flexographic ink for cigarette packaging paper according to claim 1, characterized in that: The photoinitiator is at least one of hydroxycyclohexane phenone, ethyl 2,4,6-trimethylbenzoylphenylphosphonate, and 2-hydroxy-2-methyl-1-phenyl-1-propanone.

7. The flexographic ink for cigarette packaging paper according to claim 1, characterized in that: The preparation method of the filling modifier comprises the following steps: S1, mixing the hydrous allophane nanotubes with anhydrous ethanol, adding 3-aminopropyltriethoxysilane, and then refluxing at 50-70° C. for 3-10 hours. After the treatment, centrifuging, washing and drying are performed to obtain the aminated hydrous allophane nanotubes; S2, adding allyl glycidyl ether to toluene, stirring and dissolving uniformly, then adding amination-modified allophane nanotubes, dispersing uniformly at room temperature, and then placing in a 60-70°C water bath and stirring at a speed of 150-250r / min for 5-10h. After the reaction is completed, removing the solvent under reduced pressure, washing and drying, to obtain modified allophane nanotubes; S3. Add 2-mercaptobenzothiazole to chloroform, stir until evenly dissolved, then add modified allophane nanotubes, stir evenly at room temperature, and then use nitrogen as a protective gas, under the conditions of ultraviolet light and a photoinitiator, stir the reaction for 1-2 hours. After the reaction is completed, remove the solvent under reduced pressure, wash and dry to obtain a filling modifier.

8. The flexographic ink for cigarette packaging paper according to claim 1, characterized in that: The mass volume ratio of the allophane nanotubes, 3-aminopropyltriethoxysilane and anhydrous ethanol is 1 g:(0.3-0.6) g:(15-35) mL.

9. The flexographic ink for cigarette packaging paper according to claim 1, characterized in that: In S2, the mass volume ratio of aminated allophane nanotubes, allyl glycidyl ether and toluene is (1.1-1.5) g:(0.22-0.44) g:(20-40) mL; in S3, the mass volume ratio of modified allophane nanotubes, 2-mercaptobenzothiazole and chloroform is (1.2-1.8) g:(0.34-0.68) g:(30-50) mL.

10. A method for preparing flexographic ink for cigarette packaging paper according to claim 1, characterized in that: The following steps are involved: (1) firstly mix the weighed polyurethane acrylate, 1,6-hexanediol diacrylate, 2-phenoxyethyl acrylate, and lauric acid methacrylate, and stir evenly to obtain a first mixed solution; (2) adding the weighed filler modifier, pigment, dispersant, and defoamer to the first mixed solution in sequence, and grinding and sieving to obtain a second mixed solution; (3) Finally, the weighed photoinitiator is added to the second mixed solution, and stirred again to obtain flexographic ink for cigarette packaging paper.

Images