An aqueous environment-friendly ink, a preparation method thereof and application thereof in printing
By combining modified nano-titanium dioxide, modified siloxane, and modified polyurethane emulsion, the problem of insufficient wetting and adhesion of water-based inks on substrates was solved, resulting in water-based environmentally friendly inks with high adhesion, water resistance, and stain resistance, thus expanding their application in the printing and packaging field.
Patent Information
- Application Number
- CN202610575907.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-04-28
- Publication Date
- 2026-07-03
AI Technical Summary
Water-based inks have insufficient wetting and adhesion on substrates such as paper and plastic films, which can easily lead to uneven ink layers or peeling, limiting their application in the printing and packaging industry.
By combining modified nano-titanium dioxide, modified siloxane, and modified polyurethane emulsion, a fluorine-containing and acid anhydride-containing polymer coating layer is formed, introducing high bond energy CF bonds and polar carboxyl groups, and utilizing hydrosilylation reaction to form a cross-linked structure, thereby improving the adhesion and water resistance of the ink.
It significantly improves the adhesion performance of water-based inks, enhances their adhesion and water resistance on substrates, reduces surface energy, and improves stain resistance and anti-aging properties.
Smart Images
Figure SMS_1 
Figure SMS_2 
Figure SMS_3
Abstract
Description
Technical Field
[0001] This invention relates to the field of inks, specifically to a water-based environmentally friendly ink, its preparation method, and its application in printing. Background Technology
[0002] Against the backdrop of increasingly stringent environmental standards, the printing and packaging industry is actively promoting the transformation and upgrading from solvent-based inks to water-based inks. Water-based inks use water as a diluent, contain no organic solvents, and have outstanding advantages such as low VOC emissions, safe use, and energy efficiency, which highly aligns with the current global advocacy of green development. However, in practical applications, water-based inks still face technical challenges: the high surface tension of water leads to insufficient wetting and adhesion of inks on substrates such as paper and plastic films, easily resulting in uneven ink layers or peeling. Therefore, improving the adhesion performance of water-based inks is of great significance for expanding their application in the printing and packaging field. To this end, this invention provides a water-based environmentally friendly ink with high adhesion performance and its preparation method. Summary of the Invention
[0003] The purpose of this invention is to provide a water-based environmentally friendly ink, its preparation method, and its application in printing, so as to solve the problems existing in the prior art.
[0004] To solve the above-mentioned technical problems, the present invention provides the following technical solution: A water-based environmentally friendly ink, wherein the water-based environmentally friendly ink is obtained by mixing modified polyurethane emulsion, modified nano titanium dioxide, deionized water, anhydrous ethanol, defoamer, wetting agent, triethylamine and chloroplatinic acid.
[0005] Preferably, the defoamer is Foamex1488, sourced from Yinhuang (Shanghai) Industrial Co., Ltd.
[0006] Preferably, the wetting agent is Superwet-360, which is from Tianjin Hepufele New Material Co., Ltd.
[0007] Preferably, the modified nano-titanium dioxide is obtained by mixing and reacting nano-titanium dioxide, trifluoroethyl methacrylate and maleic anhydride, and then grafting 3-buten-1-ol.
[0008] Preferably, the nano-titanium dioxide is of type R-104 and comes from Shenzhen Epuno Chemical Co., Ltd.
[0009] Preferably, the modified polyurethane emulsion is obtained by reacting isophorone diisocyanate, modified siloxane, polypentyl adipate diol, 2,2-dimethylolpropionic acid and 1,4-butanediol.
[0010] Preferably, the poly(neopentyl adipate) glycol has a molecular weight of 2000 and is sourced from Hubei Langbowan Biopharmaceutical Co., Ltd.
[0011] Preferably, the modified siloxane is obtained by grafting 2-(2'-hydroxy-3'-methallyl-5'-methylphenyl)benzotriazole onto dimethyldiethoxysilane, 1,1,3,3-tetramethyldisiloxane and hydroxypropylpentamethyldisiloxane.
[0012] A method for preparing a water-based environmentally friendly ink includes the following preparation steps: (1) Mix nano-titanium dioxide, trifluoroethyl methacrylate, maleic anhydride and tetrahydrofuran in a mass ratio of 1:(0.2~0.3):(0.1~0.2):(9~11), sonicate for 5~15 min, heat to 70~80℃ in a nitrogen atmosphere, add potassium persulfate at 0.01~0.02 times the mass of nano-titanium dioxide, stir for 1~3 h, cool naturally to room temperature, filter, wash with deionized water 3~5 times, and dry at 50~60℃ for 6~8 h to obtain pre-modified nano-titanium dioxide; (2) Mix the pre-modified nano titanium dioxide, 3-buten-1-ol and tetrahydrofuran at a mass ratio of 1:(0.1~0.2):(45~55), sonicate for 20~30 min, stir at 200~400 r / min for 4~6 h in a nitrogen atmosphere, raise the temperature to 75~85℃, and cool naturally to room temperature. Filter the mixture, wash it with deionized water 3~5 times, and dry it at 55~65℃ for 5~7 h to obtain modified nano titanium dioxide. (3) Mix dimethyldiethoxysilane, 1,1,3,3-tetramethyldisiloxane and tetramethylammonium hydroxide silanoate at a mass ratio of 1:(0.75~0.85):(0.01~0.03), purge with nitrogen for 5~15 min, stir at 85~95℃ and 100~200 rpm for 2~3 h, add 0.3~0.4 times the mass of dimethyldiethoxysilane with hydroxypropylpentamethyldisiloxane, raise the temperature to 95~105℃ and continue stirring for 7~9 h, raise the temperature to 1 at a rate of 10~20℃ / min. Continue stirring at 30-140℃ for 40-50 min, distill at 0.1-0.3 MPa for 1-2 h, add 0.01-0.03 times the mass of dimethyldiethoxysilane in chloroplatinic acid and 0.7-0.8 times the mass of dimethyldiethoxysilane in 2-(2'-hydroxy-3'-methallyl-5'-methylphenyl)benzotriazole, continue stirring at 90-100℃ under a nitrogen atmosphere for 4-6 h, let stand for 25-35 min, filter, and rotary evaporate at 50-70℃ for 1-2 h to obtain modified siloxane; (4) Mix isophorone diisocyanate and dibutyltin dilaurate at a mass ratio of 1:(0.004~0.006), heat to 85~95℃ and stir for 1~2h, cool to 45~55℃, add 0.1~0.2 times the mass of isophorone diisocyanate and modified siloxane, heat to 85~95℃ and continue stirring for 1~2h, cool to 45~55℃, add 1.9~2.1 times the mass of isophorone diisocyanate and poly(neopentyl adipate) glycol, heat to 85~95℃ and continue stirring for 2~4h until the NCO content reaches the theoretical value, cool to 45~55℃ and add isophorone diisocyanate and modified siloxane. 1,4-Butanediol and 2,2-dimethylolpropionic acid, in amounts of 0.06-0.08 times the mass of cyanate and 0.11-0.13 times the mass of isophorone diisocyanate, were added. The mixture was heated to 75-85℃, and propanol was added to adjust the viscosity. The chain was extended for 3-5 hours. The mixture was then cooled to 45-55℃, and dibutyltin dilaurate, in amounts of 0.009-0.011 times the mass of isophorone diisocyanate, was added. The mixture was reacted at 65-75℃ for 3-5 hours. Triethylamine was added for neutralization. Deionized water, in amounts of 0.3-0.5 times the total volume, was added at a speed of 800-1000 r / min. The mixture was stirred at room temperature for 25-35 minutes to obtain a modified polyurethane emulsion. (5) By mass, mix 29-31 parts of modified polyurethane emulsion, 26-28 parts of modified nano titanium dioxide, 14-16 parts of deionized water, 9-11 parts of anhydrous ethanol, 1-3 parts of defoamer and 0.9-1.1 parts of wetting agent, stir and grind for 10-20 minutes, add 4-6 parts of triethylamine and 0.4-0.5 parts of chloroplatinic acid pre-dissolved in anhydrous ethanol, continue grinding for 25-35 minutes, and adjust the pH of the system to 7.5-8.5 to obtain water-based environmentally friendly ink.
[0013] Preferably, the reaction equation for the pre-modified nano-titanium dioxide in step (1) is:
[0014] Preferably, the reaction equation for the modified nano-titanium dioxide in step (2) is:
[0015] Preferably, the reaction equation for the modified siloxane in step (3) is:
[0016] The application of a water-based environmentally friendly ink in printing, wherein flexographic printing process is adopted, and the printing parameters are as follows: printing speed 90~110m / min, substrate thickness 0.13~0.15mm, anilox roller mesh number 200~400 mesh, single ink application amount 95~105mL, power 1.9~2.1kW.
[0017] Compared with the prior art, the beneficial effects achieved by the present invention are: In preparing water-based environmentally friendly ink, this invention involves mixing and reacting nano-titanium dioxide, trifluoroethyl methacrylate, and maleic anhydride, followed by grafting 3-buten-1-ol to obtain modified nano-titanium dioxide; reacting dimethyldiethoxysilane, 1,1,3,3-tetramethyldisiloxane, and hydroxypropylpentamethyldisiloxane, followed by grafting 2-(2'-hydroxy-3'-methallyl-5'-methylphenyl)benzotriazole to obtain modified siloxane; reacting isophorone diisocyanate, modified siloxane, neopentyl adipate diol, 2,2-dimethylolpropionic acid, and 1,4-butanediol to obtain modified polyurethane emulsion; and then mixing the modified polyurethane emulsion, modified nano-titanium dioxide, deionized water, anhydrous ethanol, defoamer, wetting agent, triethylamine, and chloroplatinic acid to obtain water-based environmentally friendly ink.
[0018] First, nano-titanium dioxide, trifluoroethyl methacrylate, and maleic anhydride are mixed and reacted, and then 3-buten-1-ol is grafted onto it to obtain modified nano-titanium dioxide. A fluorine-containing and anhydride-containing polymer coating layer is formed on the surface of the nano-titanium dioxide through free radical polymerization, improving the dispersibility of the titanium dioxide while introducing high-bond-energy CF bonds, reducing surface energy, and improving the ink's water resistance and stain resistance. Using maleic anhydride as a reaction site, 3-buten-1-ol is grafted onto the surface of the titanium dioxide to form polar carboxyl groups, which interact with the polar sites of the substrate, improving ink adhesion. Simultaneously, carbon-carbon double bonds are introduced to provide reaction sites for subsequent hydrosilylation, further enhancing adhesion.
[0019] Secondly, a modified siloxane was obtained by reacting dimethyldiethoxysilane, 1,1,3,3-tetramethyldisiloxane, and hydroxypropylpentamethyldisiloxane, followed by grafting 2-(2'-hydroxy-3'-methylallyl-5'-methylphenyl)benzotriazole. A modified polyurethane emulsion was obtained by reacting isophorone diisocyanate, the modified siloxane, polypentyl adipate diol, 2,2-dimethylolpropionic acid, and 1,4-butanediol. Finally, a modified polyurethane emulsion containing high-bond-energy Si-O bonds was synthesized. The low surface energy modified siloxane utilizes hydroxypropylpentamethyldisiloxane to form single-terminal hydroxyl groups, integrating the siloxane into the polyurethane main chain to improve water resistance and stain resistance. Simultaneously, 1,1,3,3-tetramethyldisiloxane introduces Si-H bonds into the long siloxane chain, and 2-(2'-hydroxy-3'-methallyl-5'-methylphenyl)benzotriazole is grafted via hydrosilylation to enhance UV absorption. This, combined with the scattering effect of nano-titanium dioxide, improves the ink's anti-aging properties.
[0020] Finally, the modified polyurethane emulsion, modified nano-titanium dioxide, deionized water, anhydrous ethanol, defoamer, wetting agent, triethylamine, and chloroplatinic acid were mixed to obtain a water-based environmentally friendly ink. The Si-H bonds retained on the side chain siloxane of the modified polyurethane emulsion were reacted with the 3-buten-1-ol double bonds grafted on the surface of nano-titanium dioxide by chloroplatinic acid to form crosslinks, thereby chemically anchoring the nano-titanium dioxide in the polyurethane / siloxane network and improving adhesion. Detailed Implementation
[0021] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.
[0022] The raw materials used in the following examples and comparative examples are all commercially available: The nano-titanium dioxide is of type R-104 and comes from Shenzhen Epuno Chemical Co., Ltd. The wetting agent is Superwet-360, which is from Tianjin Hepufeile New Material Co., Ltd. The defoamer is Foamex 1488, sourced from Yinhuang (Shanghai) Industrial Co., Ltd. The poly(pentylene adipate) diol has a molecular weight of 2000 and is sourced from Hubei Langbowan Biopharmaceutical Co., Ltd.
[0023] Example 1
[0024] A method for preparing a water-based environmentally friendly ink, the method comprising the following preparation steps: (1) Mix nano-titanium dioxide, trifluoroethyl methacrylate, maleic anhydride and tetrahydrofuran in a mass ratio of 1:0.2:0.1:9, sonicate for 5 min, heat to 70 °C in a nitrogen atmosphere, add potassium persulfate at 0.01 times the mass of nano-titanium dioxide, stir for 3 h, cool naturally to room temperature, filter, wash 3 times with deionized water, and dry at 50 °C for 8 h to obtain pre-modified nano-titanium dioxide; (2) The pre-modified nano titanium dioxide, 3-buten-1-ol and tetrahydrofuran were mixed at a mass ratio of 1:0.1:45, sonicated for 30 min, heated to 75 °C and stirred at 200 r / min for 6 h in a nitrogen atmosphere, cooled naturally to room temperature and filtered, washed 3 times with deionized water and dried at 55 °C for 7 h to obtain modified nano titanium dioxide. (3) Dimethyldiethoxysilane, 1,1,3,3-tetramethyldisiloxane and tetramethylammonium hydroxide siloxane were mixed at a mass ratio of 1:0.75:0.01, nitrogen gas was passed through for 5 min, and the mixture was stirred at 85°C and 100 rpm for 3 h. Hydroxypropylpentamethyldisiloxane was added at a mass ratio of 0.3 times that of dimethyldiethoxysilane. The mixture was heated to 95°C and stirred for 9 h. The mixture was heated to 130°C at a rate of 10°C / min and stirred for 50 min. The mixture was distilled at 0.1 MPa for 2 h. Chloroplatinic acid at a mass ratio of 0.01 times that of dimethyldiethoxysilane and 2-(2'-hydroxy-3'-methallyl-5'-methylphenyl)benzotriazole at a mass ratio of 0.7 times that of dimethyldiethoxysilane were added. The mixture was stirred at 90°C under a nitrogen atmosphere for 6 h. After standing for 25 min, the mixture was filtered and then rotary evaporated at 50°C for 2 h to obtain the modified siloxane. (4) Mix isophorone diisocyanate and dibutyltin dilaurate at a mass ratio of 1:0.004, heat to 85°C and stir for 2 hours, then cool to 45°C and add 0.1 times the mass of modified siloxane to isophorone diisocyanate. Heat to 85°C and continue stirring for 2 hours, then cool to 45°C and add 1.9 times the mass of neopentyl adipate diol to isophorone diisocyanate. Heat to 85°C and continue stirring for 4 hours, then cool to 45°C and add 0 times the mass of isophorone diisocyanate to isophorone diisocyanate. 0.06 times the mass of 1,4-butanediol and 0.11 times the mass of isophorone diisocyanate of 2,2-dimethylolpropionic acid were added, and the mixture was heated to 75°C. Propanol was added to adjust the viscosity, and the chain was extended for 5 hours. The mixture was then cooled to 45°C, and 0.009 times the mass of isophorone diisocyanate of dibutyltin dilaurate was added. The mixture was reacted at 65°C for 5 hours, and then triethylamine was added for neutralization. At a speed of 800 r / min, 0.3 times the total volume of deionized water was added, and the mixture was stirred at room temperature for 35 minutes to obtain a modified polyurethane emulsion. (5) By mass, 29 parts of modified polyurethane emulsion, 28 parts of modified nano titanium dioxide, 16 parts of deionized water, 11 parts of anhydrous ethanol, 3 parts of defoamer and 1.1 parts of wetting agent are mixed and stirred and ground for 10 min. 6 parts of triethylamine and 0.5 parts of chloroplatinic acid pre-dissolved in anhydrous ethanol are added and ground for another 25 min. The pH of the system is adjusted to 7.5 to obtain water-based environmentally friendly ink.
[0025] Example 2
[0026] A method for preparing a water-based environmentally friendly ink, the method comprising the following preparation steps: (1) Mix nano-titanium dioxide, trifluoroethyl methacrylate, maleic anhydride and tetrahydrofuran in a mass ratio of 1:0.25:0.15:10, sonicate for 10 min, heat to 75 °C in a nitrogen atmosphere, add potassium persulfate at 0.015 times the mass of nano-titanium dioxide, stir for 2 h, cool naturally to room temperature, filter, wash 4 times with deionized water, and dry at 55 °C for 7 h to obtain pre-modified nano-titanium dioxide; (2) The pre-modified nano titanium dioxide, 3-buten-1-ol and tetrahydrofuran were mixed at a mass ratio of 1:0.15:50, sonicated for 25 min, heated to 80 °C and stirred at 300 r / min for 5 h in a nitrogen atmosphere, cooled naturally to room temperature and filtered, washed 4 times with deionized water, and dried at 60 °C for 6 h to obtain modified nano titanium dioxide. (3) Dimethyldiethoxysilane, 1,1,3,3-tetramethyldisiloxane and tetramethylammonium hydroxide siloxane were mixed in a mass ratio of 1:0.8:0.02, nitrogen gas was passed through for 10 min, and the mixture was stirred at 90 °C and 150 rpm for 2.5 h. Hydroxypropylpentamethyldisiloxane was added at 0.35 times the mass of dimethyldiethoxysilane, the temperature was raised to 100 °C and stirred for 8 h. The temperature was raised to 135 °C at a rate of 15 °C / min and stirred for 45 min. The mixture was distilled at 0.2 MPa for 1.5 h. Chloroplatinic acid at 0.02 times the mass of dimethyldiethoxysilane and 2-(2'-hydroxy-3'-methallyl-5'-methylphenyl)benzotriazole at 0.75 times the mass of dimethyldiethoxysilane were added. The mixture was stirred at 95 °C in a nitrogen atmosphere for 5 h. After standing for 30 min, the mixture was filtered and then rotary evaporated at 60 °C for 1.5 h to obtain the modified siloxane. (4) Mix isophorone diisocyanate and dibutyltin dilaurate at a mass ratio of 1:0.005, heat to 90°C and stir for 1.5 h, cool to 50°C, add 0.15 times the mass of modified siloxane to isophorone diisocyanate, heat to 90°C and continue stirring for 1.5 h, cool to 50°C, add 2 times the mass of poly(neopentyl adipate) glycol, heat to 80°C and continue stirring for 3 h, cool to 50°C, and add isophorone diisocyanate... 0.07 times the mass of 1,4-butanediol and 0.12 times the mass of isophorone diisocyanate of 2,2-dimethylolpropionic acid were added, and the mixture was heated to 80°C. Propanol was added to adjust the viscosity, and the chain was extended for 4 hours. The mixture was then cooled to 50°C, and 0.01 times the mass of isophorone diisocyanate of dibutyltin dilaurate was added. The mixture was reacted at 70°C for 4 hours, and triethylamine was added to neutralize the mixture. At a speed of 900 r / min, 0.4% of the total volume of deionized water was added, and the mixture was stirred at room temperature for 30 minutes to obtain a modified polyurethane emulsion. (5) By mass, mix 30 parts of modified polyurethane emulsion, 27 parts of modified nano titanium dioxide, 15 parts of deionized water, 10 parts of anhydrous ethanol, 2 parts of defoamer and 1 part of wetting agent, stir and grind for 15 min, add 5 parts of triethylamine and 0.45 parts of chloroplatinic acid pre-dissolved in anhydrous ethanol, continue grinding for 30 min, and adjust the pH of the system to 8 to obtain water-based environmentally friendly ink.
[0027] Example 3
[0028] A method for preparing a water-based environmentally friendly ink, the method comprising the following preparation steps: (1) Mix nano-titanium dioxide, trifluoroethyl methacrylate, maleic anhydride and tetrahydrofuran in a mass ratio of 1:0.3:0.2:11, sonicate for 15 min, heat to 80 °C in a nitrogen atmosphere, add potassium persulfate at 0.02 times the mass of nano-titanium dioxide, stir for 1 h, cool naturally to room temperature, filter, wash 5 times with deionized water, and dry at 60 °C for 6 h to obtain pre-modified nano-titanium dioxide; (2) The pre-modified nano titanium dioxide, 3-buten-1-ol and tetrahydrofuran were mixed in a mass ratio of 1:0.2:55, sonicated for 30 min, heated to 85 °C and stirred at 400 r / min for 4 h in a nitrogen atmosphere, cooled naturally to room temperature and filtered, washed 5 times with deionized water and dried at 65 °C for 5 h to obtain modified nano titanium dioxide. (3) Dimethyldiethoxysilane, 1,1,3,3-tetramethyldisiloxane and tetramethylammonium hydroxide siloxane were mixed at a mass ratio of 1:0.85:0.03, nitrogen gas was passed through for 15 min, and the mixture was stirred at 95 °C and 200 rpm for 2 h. Hydroxypropylpentamethyldisiloxane was added at a mass ratio of 0.4 times that of dimethyldiethoxysilane. The mixture was heated to 105 °C and stirred for 7 h. The mixture was heated to 140 °C at a rate of 20 °C / min and stirred for 40 min. The mixture was distilled at 0.3 MPa for 1 h. Chloroplatinic acid at a mass ratio of 0.03 times that of dimethyldiethoxysilane and 2-(2'-hydroxy-3'-methallyl-5'-methylphenyl)benzotriazole at a mass ratio of 0.8 times that of dimethyldiethoxysilane were added. The mixture was stirred at 100 °C under a nitrogen atmosphere for 4 h. After standing for 35 min, the mixture was filtered and then rotary evaporated at 70 °C for 1 h to obtain the modified siloxane. (4) Mix isophorone diisocyanate and dibutyltin dilaurate at a mass ratio of 1:0.006, heat to 95°C and stir for 1 hour, cool to 55°C, add 0.2 times the mass of modified siloxane to isophorone diisocyanate, heat to 95°C and continue stirring for 1 hour, cool to 55°C, add 2.1 times the mass of poly(neopentyl adipate) glycol, heat to 95°C and continue stirring for 2 hours, cool to 55°C, add 0. 0.08 times the mass of 1,4-butanediol and 0.13 times the mass of isophorone diisocyanate of 2,2-dimethylolpropionic acid were added, heated to 85℃, and propanol was added to adjust the viscosity. The chain extension was carried out for 3 hours. The temperature was lowered to 55℃, and 0.011 times the mass of isophorone diisocyanate of dibutyltin dilaurate was added. The reaction was carried out at 75℃ for 3 hours. Triethylamine was added for neutralization. At a speed of 1000 r / min, 0.5 times the total volume of deionized water was added. The mixture was stirred at room temperature for 25 minutes to obtain a modified polyurethane emulsion. (5) By mass, mix 31 parts of modified polyurethane emulsion, 26 parts of modified nano titanium dioxide, 14 parts of deionized water, 9 parts of anhydrous ethanol, 1 part of defoamer and 0.9 parts of wetting agent, stir and grind for 20 min, add 4 parts of triethylamine and 0.4 parts of 0.5 parts of chloroplatinic acid pre-dissolved in anhydrous ethanol, continue grinding for 35 min, and adjust the pH of the system to 8.5 min to obtain water-based environmentally friendly ink.
[0029] Comparative Example 1: The difference between the preparation method of the water-based environmentally friendly ink in Comparative Example 1 and Example 2 lies only in the difference between steps (1) and (2). Step (2) is omitted, and step (1) is modified as follows: Nano titanium dioxide, trifluoroethyl methacrylate, maleic anhydride, and tetrahydrofuran are mixed in a mass ratio of 1:0.25:0.15:10, sonicated for 10 min, heated to 75°C in a nitrogen atmosphere, and potassium persulfate with a mass of 0.015 times that of nano titanium dioxide is added. The mixture is stirred for 2 h, naturally cooled to room temperature, filtered, washed 4 times with deionized water, and dried at 55°C for 7 h to obtain modified nano titanium dioxide. The remaining steps are the same as in Example 2.
[0030] Comparative Example 2: The preparation method of the water-based environmentally friendly ink in Comparative Example 2 differs from that in Example 2 only in steps (1) and (2), which are omitted. The remaining steps are the same as in Example 2.
[0031] Comparative Example 3: The preparation method of the water-based environmentally friendly ink in Comparative Example 3 differs from that in Example 2 only in step (3). Step (3) is modified as follows: Dimethyldiethoxysilane, 1,1,3,3-tetramethyldisiloxane, and tetramethylammonium hydroxide silanolate are mixed at a mass ratio of 1:0.8:0.02, nitrogen is purged for 10 min, and the mixture is stirred at 90°C and 150 rpm for 2.5 h. Hydroxypropylpentamethyldisiloxane is added at a mass ratio of 0.35 times that of dimethyldiethoxysilane, the temperature is raised to 100°C and stirring is continued for 8 h. The temperature is then raised to 135°C at a rate of 15°C / min and stirring is continued for 45 min. The mixture is then distilled at 0.2 MPa for 1.5 h to obtain the modified siloxane. The remaining steps are the same as in Example 2.
[0032] Comparative Example 4: The preparation method of the water-based environmentally friendly ink in Comparative Example 4 differs from that in Example 2 only in step (3), which is omitted. The remaining steps are the same as in Example 2.
[0033] The flexographic printing process steps for the sample to be tested are as follows: (1) Printing equipment and materials: A flexographic printing press is used, the substrate is polyethylene film with a thickness of 0.14mm, the anilox roller is made of ceramic and has a mesh count of 300.
[0034] (2) Printing process parameter settings: The water-based environmentally friendly ink prepared in the embodiments and comparative examples of the present invention is injected into the ink fountain, the printing speed is controlled at 100m / min, the doctor blade angle is adjusted to 35°, the doctor blade pressure is set to 0.2MPa, and the temperature of the drying zone is controlled at 70℃.
[0035] (3) Printing operation: Start the printing press, adjust the ink supply system to transfer the ink evenly to the printing plate, and control the ink amount per batch to 100mL; after passing through the 80℃ drying zone and the room temperature drying zone, the sample to be tested is obtained.
[0036] Test example: Adhesion test method: The test samples obtained from each embodiment and comparative example were adhered to the ink surface of the test sample with 3M 600 tape, pressed firmly, and then torn off. The tape was held at a 60° angle to the plastic film, and the tape was slowly pulled off to observe the peeling. A 10mm × 10mm semi-transparent millimeter grid paper was fixed to the pressure part of the sample, and the number of grids covered by the tape (A1) and the number of grids occupied by the torn ink (A2) were counted respectively. The peeling rate Q1 was calculated as Q1 = A1 / (A1 + A2) * 100%.
[0037] Water resistance test method: Immerse 2 / 3 of the ink area of the test sample obtained from each example and comparative example in deionized water at 25°C, observe whether the ink peels off or whether the color of the water changes, and record the peeling time and water resistance performance.
[0038] Anti-aging test method: The test samples obtained from each example and comparative example were placed in an ultraviolet irradiation environment for 120 h (λ=365 nm, 1 W / cm²). 2 After removing the sample from the oven at 25°C, apply 3M 600 tape to the ink surface of the sample, press firmly, and then tear it off. Hold the tape at a 60° angle to the plastic film and slowly pull it off, observing the peeling. Fix a 10mm × 10mm semi-transparent millimeter grid paper to the pressure area of the sample, and count the number of grids covered by the tape (A1) and the number of grids occupied by the torn ink (A2). Calculate the peeling rate Q2 = A1 / (A1+A2)*100%, and calculate the aging rate = (Q1-Q2) / Q1*100%.
[0039] Stain resistance test method: For the test samples obtained from each embodiment and comparative example, soy sauce was dripped onto the ink surface of the test sample, and after 3 hours, it was rinsed with deionized water. The presence of any residue was observed to determine the stain resistance.
[0040] Table 1 shedding rate % Shedding time h Aging rate % Imprint Residue Example 1 4.62 11.38 9.75 No mark Example 2 4.17 11.96 9.42 No mark Example 3 4.89 11.55 9.81 No mark Comparative Example 1 18.15 11.27 9.93 No mark Comparative Example 2 21.94 8.51 54.25 Slight edge residue Comparative Example 3 22.79 11.30 49.87 No mark Comparative Example 4 26.13 7.18 50.06 Edge imprint residue A comparison of the experimental data from Examples 1-3 and Comparative Examples 1-4 in Table 1 reveals that the water-based environmentally friendly ink prepared by this invention has good adhesion, water resistance, anti-aging properties, and anti-fouling properties.
[0041] Comparative Example 1 was not grafted with 3-buten-1-ol. By comparison, Examples 1, 2, and 3 had lower peeling rates than Comparative Example 1, indicating that grafting 3-buten-1-ol using maleic anhydride as a reaction site forms polar carboxyl groups on the titanium dioxide surface, which interact with the polar sites of the substrate, improving ink adhesion. At the same time, the introduction of carbon-carbon double bonds provides reaction sites for subsequent hydrosilylation, further enhancing adhesion.
[0042] Compared with Comparative Example 2, which was unmodified nano-titanium dioxide, Examples 1, 2, and 3 showed lower peeling and aging rates, longer peeling times, and no residue compared to Comparative Example 2. This indicates that the formation of a fluorine-containing and anhydride-containing polymer coating layer on the surface of nano-titanium dioxide through free radical polymerization improves the dispersibility of titanium dioxide and enhances its UV shielding properties. Simultaneously, the introduction of high-bond-energy CF bonds reduces surface energy, improving the ink's water resistance and stain resistance. The grafting of 3-buten-1-ol with maleic anhydride as a reaction site forms polar carboxyl groups on the titanium dioxide surface, which interact with the polar sites of the substrate, improving ink adhesion. The introduced carbon-carbon double bonds provide reaction sites for subsequent hydrosilylation, further enhancing adhesion.
[0043] Comparative Example 3, which was not grafted with 2-(2'-hydroxy-3'-methallyl-5'-methylphenyl)benzotriazole, showed lower peeling and aging rates compared to Comparative Example 3. This indicates that 1,1,3,3-tetramethyldisiloxane contains Si-H bonds in the long siloxane chain. Grafting 2-(2'-hydroxy-3'-methallyl-5'-methylphenyl)benzotriazole via hydrosilylation enhances UV absorption and synergistically improves the scattering of nano-titanium dioxide, thereby increasing the ink's anti-aging properties. Simultaneously, the Si-H bonds retained on the siloxane side chain of the chloroplatinic acid-catalyzed modified polyurethane emulsion react with the 3-buten-1-ol double bonds grafted onto the surface of nano-titanium dioxide to form crosslinks, chemically anchoring the nano-titanium dioxide within the polyurethane / siloxane network and enhancing adhesion.
[0044] Comparative Example 4 did not graft modified siloxane onto the polyurethane. By comparison, Examples 1, 2, and 3 showed lower peeling and aging rates, longer peeling times, and no residue compared to Comparative Example 3. This demonstrates that by synthesizing modified siloxanes containing high-bond-energy Si-O bonds and low surface energy, and utilizing hydroxypropylpentamethyldisiloxane to form single-terminal hydroxyl groups, the siloxane is incorporated into the polyurethane backbone, improving water resistance and stain resistance. Simultaneously, 1,1,3,3-tetramethyldisiloxane introduces Si-H bonds into the long siloxane chain. By grafting 2-(2'-hydroxy-3'-methallyl-5'-methylphenyl)benzotriazole via hydrosilylation, the UV absorption effect is enhanced, and the scattering of nano-titanium dioxide is synergistically improved, thus enhancing the ink's anti-aging properties. The Si-H bonds retained on the siloxane side chain of the chloroplatinic acid-catalyzed polyurethane emulsion react with the 3-buten-1-ol double bonds grafted onto the surface of nano-titanium dioxide to form crosslinks, chemically anchoring the nano-titanium dioxide in the polyurethane / siloxane network and improving adhesion.
[0045] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.
Claims
1. An aqueous eco-friendly ink, characterized by, The water-based environmentally friendly ink is obtained by mixing modified polyurethane emulsion, modified nano titanium dioxide, deionized water, anhydrous ethanol, defoamer, wetting agent, triethylamine and chloroplatinic acid. The modified nano-titanium dioxide is obtained by mixing and reacting nano-titanium dioxide, trifluoroethyl methacrylate and maleic anhydride, and then grafting 3-buten-1-ol. The modified polyurethane emulsion is obtained by reacting isophorone diisocyanate, modified siloxane, polypentyl adipate diol, 2,2-dimethylolpropionic acid and 1,4-butanediol. The modified siloxane is obtained by grafting 2-(2'-hydroxy-3'-methallyl-5'-methylphenyl)benzotriazole onto dimethyldiethoxysilane, 1,1,3,3-tetramethyldisiloxane and hydroxypropylpentamethyldisiloxane.
2. A method for preparing an aqueous eco-friendly ink, characterized by, The preparation steps include the following: (1) Mix pre-modified nano-titanium dioxide, 3-buten-1-ol and tetrahydrofuran at a mass ratio of 1:(0.1~0.2):(45~55), sonicate for 20~30 min, stir at 200~400 r / min for 4~6 h in a nitrogen atmosphere, raise the temperature to 75~85℃, and cool naturally to room temperature. Filter, wash with deionized water 3~5 times, and dry at 55~65℃ for 5~7 h to obtain modified nano-titanium dioxide; (2) Mix dimethyldiethoxysilane, 1,1,3,3-tetramethyldisiloxane and tetramethylammonium hydroxide silanolate at a mass ratio of 1:(0.75~0.85):(0.01~0.03), purge with nitrogen for 5~15 min, stir at 85~95℃ and 100~200 rpm for 2~3 h, add hydroxypropylpentamethyldisiloxane, raise the temperature to 95~105℃ and continue stirring for 7~9 h, and then stir at 10~20℃. Heating to 130-140℃ at a rate of 0.5 min and stirring for 40-50 min were continued. Distillation was carried out at 0.1-0.3 MPa for 1-2 h. Chloroplatinic acid and 2-(2'-hydroxy-3'-methallyl-5'-methylphenyl)benzotriazole were added. Stirring was continued at 90-100℃ under a nitrogen atmosphere for 4-6 h. After standing for 25-35 min, the mixture was filtered and rotary evaporated at 50-70℃ for 1-2 h to obtain the modified siloxane. (3) Mix isophorone diisocyanate and dibutyltin dilaurate at a mass ratio of 1:(0.004~0.006), heat to 85~95℃ and stir for 1~2 hours, cool to 45~55℃, add modified siloxane, heat to 85~95℃ and continue stirring for 1~2 hours, cool to 45~55℃, add poly(neopentyl adipate) glycol, heat to 85~95℃ and continue stirring for 2~4 hours until the NCO content reaches the theoretical value, cool to 45~55℃, and add 0.0% of isophorone diisocyanate. Add 6-0.08 times the mass of 1,4-butanediol and 0.11-0.13 times the mass of isophorone diisocyanate and 2,2-dimethylolpropionic acid. Heat to 75-85℃, add propanol to adjust viscosity, extend chain for 3-5 hours, cool to 45-55℃, add dibutyltin dilaurate, react at 65-75℃ for 3-5 hours, add triethylamine to neutralize, add 0.3-0.5 times the total volume of deionized water at 800-1000 r / min, stir at room temperature for 25-35 minutes to obtain modified polyurethane emulsion; (4) By mass, mix 29-31 parts of modified polyurethane emulsion, 26-28 parts of modified nano titanium dioxide, 14-16 parts of deionized water, 9-11 parts of anhydrous ethanol, 1-3 parts of defoamer and 0.9-1.1 parts of wetting agent, stir and grind for 10-20 minutes, add 4-6 parts of triethylamine and 0.4-0.5 parts of chloroplatinic acid pre-dissolved in anhydrous ethanol, continue grinding for 25-35 minutes, and adjust the pH of the system to 7.5-8.5 to obtain water-based environmentally friendly ink.
3. The method for preparing a water-based environmentally friendly ink according to claim 2, characterized in that, The preparation process of the pre-modified nano-titanium dioxide in step (1) is as follows: nano-titanium dioxide, trifluoroethyl methacrylate, maleic anhydride and tetrahydrofuran are mixed in a mass ratio of 1:(0.2~0.3):(0.1~0.2):(9~11), sonicated for 5~15 min, heated to 70~80℃ in a nitrogen atmosphere, potassium persulfate of 0.01~0.02 times the mass of nano-titanium dioxide is added, stirred for 1~3 h, cooled naturally to room temperature and filtered, washed 3~5 times with deionized water, and dried at 50~60℃ for 6~8 h to obtain the product.
4. The method for preparing a water-based environmentally friendly ink according to claim 2, characterized in that, The amount of hydroxypropyl pentamethyldisiloxane added in step (2) is 0.3 to 0.4 times the mass of dimethyldiethoxysilane.
5. The method for preparing a water-based environmentally friendly ink according to claim 2, characterized in that, The amount of chloroplatinic acid added in step (2) is 0.01 to 0.03 times the mass of dimethyldiethoxysilane.
6. The method for preparing a water-based environmentally friendly ink according to claim 2, characterized in that, The amount of 2-(2'-hydroxy-3'-methallyl-5'-methylphenyl)benzotriazole added in step (2) is 0.7 to 0.8 times the mass of dimethyldiethoxysilane.
7. The method for preparing a water-based environmentally friendly ink according to claim 2, characterized in that, The amount of modified siloxane added in step (3) is 0.1 to 0.2 times the mass of isophorone diisocyanate.
8. The method for preparing a water-based environmentally friendly ink according to claim 2, characterized in that, The amount of poly(neopentyl adipate) diol added in step (3) is 1.9 to 2.1 times the mass of isophorone diisocyanate.
9. The method for preparing a water-based environmentally friendly ink according to claim 2, characterized in that, The amount of dibutyltin dilaurate added in step (3) is 0.009 to 0.011 times the mass of isophorone diisocyanate.
10. Use of the water-based eco-friendly ink according to claim 1 in printing.