Sun-proof water-based ink for printing special paper and preparation method of sun-proof water-based ink

Abstract

The invention discloses sun-proof water-based ink for special paper printing and a preparation method thereof, and belongs to the technical field of ink. Comprising the following steps: carrying out esterification reaction on maleated rosin macrogol ester and methacrylic acid to obtain modified methacrylate; mixing an emulsifier, an initiator and deionized water, adding modified methacrylate, butyl acrylate, acrylic acid and hydroxypropyl acrylate, uniformly stirring, heating to 82 DEG C, stirring for 3-4 hours, heating to 88 DEG C, keeping the temperature for 2-3 hours, and adjusting the pH value to 7-8 to obtain a binder; the preparation method comprises the following steps: uniformly mixing and shearing a binder, a pigment, a defoaming agent, a dispersing agent, a thickening agent, a wetting agent, a flatting agent, a sun-proof factor, an antioxidant and deionized water, adjusting the pH value to 8-9, and discharging, thereby obtaining the water-based ink with excellent sun-proof performance for printing special paper.

Description

Technical Field

[0001] This invention belongs to the field of ink technology, specifically relating to a lightfast water-based ink for printing on special paper and its preparation method. Background Technology

[0002] Water-based inks, with their advantages of using water as a dispersion medium and low VOC emissions, are gradually replacing solvent-based inks as the mainstream choice for specialty paper printing. Specialty paper, as an important branch of printing substrates, encompasses multiple categories such as thermal paper, anti-counterfeiting paper, food packaging paper, and outdoor signage paper. Printed products on specialty paper often need to meet the requirements of long-term preservation (e.g., archival documents), outdoor exposure (e.g., posters and signs), or high-end display (e.g., jewelry gift boxes), placing rigid demands on the lightfastness of inks. Although solvent-based inks can achieve high lightfastness by adding solvent-based light stabilizers, their excessive VOC emissions have led to explicit restrictions on their use in specialty paper printing under EU regulations and my country's environmental protection plans. Therefore, developing a water-based ink that combines environmental friendliness with high lightfastness and compatibility with various specialty paper substrates is key to resolving current technological contradictions and is of great significance for promoting the green transformation of the printing industry and expanding the application of specialty paper. Summary of the Invention

[0003] The purpose of this invention is to provide a lightfast water-based ink for printing on special paper and its preparation method, which improves the lightfastness of water-based inks.

[0004] The objective of this invention can be achieved through the following technical solutions:

[0005] A method for preparing a lightfast water-based ink for printing on special paper includes the following steps:

[0006] S1. Modified methacrylate is obtained by esterification reaction of maleic rosin polyethylene glycol ester and methacrylic acid.

[0007] S2. Take the emulsifier, initiator and deionized water and mix them evenly. Add the modified methacrylate, butyl acrylate, acrylic acid and hydroxypropyl acrylate and stir evenly. Heat to 82°C and stir for 3-4 hours. Heat to 88°C and keep warm for 2-3 hours. Adjust the pH to 7-8 to obtain the binder.

[0008] S3. Take the binder, pigment, defoamer, dispersant, thickener, wetting agent, leveling agent, sun-resistant factor, antioxidant, film-forming aid, and deionized water, mix and cut evenly, and adjust the pH to 8-9 to obtain the sun-resistant water-based ink for special paper printing.

[0009] The sun-resistant factor is nano-silver-doped zinc oxide coated calcium carbonate powder.

[0010] As a preferred embodiment of the present invention, in step S2, the mass ratio of the emulsifier, initiator, deionized water, modified methacrylate, butyl acrylate, acrylic acid, and hydroxypropyl acrylate is 3-5:1-2:80:15-25:20-30:4-6:18-24.

[0011] As a preferred embodiment of the present invention, in step S3, the mass ratio of the binder, pigment, defoamer, dispersant, thickener, wetting agent, leveling agent, sun-resistant agent, antioxidant, film-forming aid, and deionized water is 40-60:10-15:1-2:0.4-0.6:0.2-0.4:3-5:1-3:4-8:1-2:1-3:35-45.

[0012] As a preferred embodiment of the present invention, the method for preparing the sun-resistant factor includes the following steps:

[0013] A1. Take nano calcium carbonate, anhydrous ethanol and deionized water, mix them, and ultrasonically disperse them for 10-20 minutes to obtain material A;

[0014] A2. Mix zinc nitrate hexahydrate, anhydrous ethanol, and deionized water, and stir for 20-30 minutes to obtain material B.

[0015] A3. Add material B dropwise to material A under water bath heating and stirring at 45℃, age for 1-2 hours, put into 100mL hydrothermal crystallization kettle, hydrothermally treat in 120℃ oven for 3-5 hours, and dry at vacuum degree 20-30Pa and temperature -20℃ for 10-20 hours to obtain nano zinc oxide coated calcium carbonate powder.

[0016] A4. Disperse the nano zinc oxide-coated calcium carbonate powder in anhydrous ethanol, add 3-isocyanate-propyltrimethoxysilane, heat and stir in a water bath at 50-60℃ for 2-4 hours, filter, take the solid phase, wash it three times with deionized water, disperse it again in deionized water, add silver nitrate solution and continue stirring for 10-20 minutes, add reducing agent, age for 8-12 hours, filter, take the solid phase, wash it three times with deionized water, and dry it at 105℃ for 8-10 hours to obtain the sun-resistant factor.

[0017] As a preferred embodiment of the present invention, in step A1, the ratio of nano-calcium carbonate, anhydrous ethanol, and deionized water is 1-1.2g: 10-12mL: 1-2mL.

[0018] As a preferred embodiment of the present invention, in step A2, the ratio of zinc nitrate hexahydrate, anhydrous ethanol, and deionized water is 0.4-0.5g: 5mL: 10-20mL.

[0019] As a preferred technical solution of the present invention, in step A4, the ratio of the nano zinc oxide coated calcium carbonate powder, anhydrous ethanol, 3-isocyanate-propyltrimethoxysilane, deionized water for dispersion, silver nitrate solution, and reducing agent is 1-1.2g:20mL:1-1.2mL:50mL:10-15mL:15mL.

[0020] As a preferred embodiment of the present invention, in step A4, the concentration of the silver nitrate solution is 0.1 mol / L.

[0021] As a preferred embodiment of the present invention, in step A4, the reducing agent is a sodium citrate solution with a concentration of 0.2 mol / L.

[0022] A lightfast water-based ink for printing on special paper, prepared using the above-described method.

[0023] The beneficial effects of this invention are:

[0024] This invention utilizes the esterification and grafting modification of maleic rosin polyethylene glycol ester and methacrylic acid as a functional monomer to produce water-based inks. The tricyclic skeleton of the maleic rosin structure can efficiently absorb ultraviolet rays, preventing ultraviolet rays from directly acting on key components such as pigments and binders in the ink, thus reducing photo-oxidative degradation reactions. On the other hand, the flexible segments of polyethylene glycol can form a steric barrier around the molecule, hindering ultraviolet-induced free radical attacks and inhibiting the curling and breakage of polymer molecular chains under light, thereby improving the photostability of the molecular chains. Furthermore, the rigid conjugated skeleton of maleic rosin is used to anchor the sun-resistant factor through π-metal coordination bonds, allowing the sun-resistant factor to be evenly distributed in the ink, forming a continuous ultraviolet protection network and fully exerting the sun-resistant protection performance. Detailed Implementation

[0025] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with embodiments, is provided below.

[0026] Example 1

[0027] A method for preparing a lightfast water-based ink for printing on special paper includes the following steps:

[0028] S1. Under a nitrogen atmosphere, maleic rosin, polyethylene glycol 200, and stannous oxalate were mixed and stirred at 245°C for 3 hours. The mixture was then evacuated to a vacuum of -0.095 MPa and held for 1 hour to remove water and low-boiling-point impurities. The mixture was filtered while hot, and the filtrate was washed three times with a 5% sodium hydroxide solution, followed by washing with deionized water until neutral. After standing and separation, the oil phase was collected to obtain maleic rosin polyethylene glycol ester. The mass ratio of maleic rosin, polyethylene glycol 200, and stannous oxalate was 1:2.1:0.02.

[0029] S2. Under a nitrogen atmosphere, the maleic rosin polyethylene glycol ester, p-toluenesulfonic acid, hydroquinone, and toluene were mixed and stirred evenly. Methacrylic acid was added, and the mixture was heated to 110°C, refluxed, and stirred for 2 hours. After cooling to room temperature, a 15% sodium chloride solution was added, stirred, and the mixture was separated. The oil layer was taken and the pH was adjusted to neutral with a 5% sodium hydroxide solution. The mixture was washed with water, and the aqueous layer was separated. The oil phase was dried overnight with anhydrous sodium sulfate, filtered, and the oil phase was separated. Toluene was removed by vacuum distillation at 60°C and a vacuum degree of 5 kPa to obtain modified methacrylic acid ester. The mass ratio of the maleic rosin polyethylene glycol ester, p-toluenesulfonic acid, hydroquinone, toluene, and methacrylic acid was 1:0.016:0.005:30:0.13.

[0030] S3. Mix emulsifier Tween 85, initiator potassium persulfate, and deionized water, stir until homogeneous, add the modified methacrylate, butyl acrylate, acrylic acid, and hydroxypropyl acrylate, stir until homogeneous, heat to 82℃ and stir for 3 hours, heat to 88℃ and hold for 2 hours, cool and discharge, adjust the pH to 7 with 0.1 mol / L ammonia water to obtain the binder; the mass ratio of the emulsifier, initiator, deionized water, modified methacrylate, butyl acrylate, acrylic acid, and hydroxypropyl acrylate is 3:1:80:15:20:4:18;

[0031] S4. Take the binder, pigment phthalocyanine blue, defoamer BYK-021, dispersant TEGO Dispers 752W, thickener ACRYSOL ASE-60, wetting agent BYK346, leveling agent BYK-333, lightfastness factor, antioxidant 1010, film-forming aid propylene glycol methyl ether acetate, and deionized water, mix them, and after shearing and homogenization, adjust the pH to 8 with 0.1 mol / L ammonia water to obtain the lightfast water-based ink for special paper printing; the mass ratio of the binder, pigment, defoamer, dispersant, thickener, wetting agent, leveling agent, lightfastness factor, antioxidant, film-forming aid, and deionized water is 40:10:1:0.4:0.2:3:1:4:1:1:35;

[0032] The method for preparing the sun protection factor includes the following steps:

[0033] A1. Take nano-calcium carbonate, anhydrous ethanol, and deionized water, mix them, and ultrasonically disperse them for 10 minutes to obtain material A; the ratio of nano-calcium carbonate, anhydrous ethanol, and deionized water is 1g:10mL:1mL.

[0034] A2. Mix zinc nitrate hexahydrate, anhydrous ethanol, and deionized water, and stir for 20 minutes to obtain material B; the ratio of zinc nitrate hexahydrate, anhydrous ethanol, and deionized water is 0.4g:5mL:10mL.

[0035] A3. Add material B dropwise to material A under water bath heating and stirring at 45℃, age for 1 hour, put into 100mL hydrothermal crystallization kettle, hydrothermally treat in 120℃ oven for 3 hours, and dry at vacuum degree 20Pa and temperature -20℃ for 10 hours to obtain nano zinc oxide coated calcium carbonate powder.

[0036] A4. Disperse the nano-zinc oxide-coated calcium carbonate powder in anhydrous ethanol, add 3-isocyanate-propyltrimethoxysilane, heat and stir in a water bath at 50°C for 2 hours, filter, wash the solid phase three times with deionized water, disperse it again in deionized water, add silver nitrate solution and continue stirring for 10 minutes, add reducing agent, age for 8 hours, filter, wash the solid phase three times with deionized water, and dry at 105°C for 8 hours to obtain the sun-resistant factor; the ratio of nano-zinc oxide-coated calcium carbonate powder, anhydrous ethanol, 3-isocyanate-propyltrimethoxysilane, deionized water for dispersion, silver nitrate solution, and reducing agent is 1g:20mL:1mL:50mL:10mL:15mL; the concentration of the silver nitrate solution is 0.1mol / L; the reducing agent is a sodium citrate solution with a concentration of 0.2mol / L.

[0037] Example 2

[0038] A method for preparing a lightfast water-based ink for printing on special paper includes the following steps:

[0039] S1. Under a nitrogen atmosphere, maleic rosin, polyethylene glycol 200, and stannous oxalate were mixed and stirred at 245°C for 4 hours. The mixture was then evacuated to a vacuum of -0.095 MPa and held for 1.5 hours to remove water and low-boiling-point impurities. The mixture was filtered while hot, and the filtrate was washed three times with a 5% sodium hydroxide solution, followed by washing with deionized water until neutral. After standing and separation, the oil phase was collected to obtain maleic rosin polyethylene glycol ester. The mass ratio of maleic rosin, polyethylene glycol 200, and stannous oxalate was 1.1:2.3:0.03.

[0040] S2. Under a nitrogen atmosphere, the aforementioned maleic rosin polyethylene glycol ester, p-toluenesulfonic acid, hydroquinone, and toluene were mixed and stirred evenly. Methacrylic acid was added, and the mixture was heated to 110°C and refluxed for 2.5 hours. After cooling to room temperature, a 15% sodium chloride solution was added and stirred. The mixture was then separated into layers. The oil layer was taken and the pH was adjusted to neutral with a 5% sodium hydroxide solution. The oil was washed with water, and the aqueous layer was separated. The oil phase was dried overnight with anhydrous sodium sulfate. The oil phase was filtered and separated. Toluene was removed by vacuum distillation at 60°C and a vacuum degree of 5 kPa to obtain modified methacrylic acid ester. The mass ratio of the aforementioned maleic rosin polyethylene glycol ester, p-toluenesulfonic acid, hydroquinone, toluene, and methacrylic acid was 1:0.017:0.0055:35:0.14.

[0041] S3. Mix emulsifier Tween 85, initiator potassium persulfate, and deionized water, stir until homogeneous, add the modified methacrylate, butyl acrylate, acrylic acid, and hydroxypropyl acrylate, stir until homogeneous, heat to 82℃ and stir for 3.5h, heat to 88℃ and hold for 2.5h, cool and discharge, adjust the pH to 8 with 0.1mol / L ammonia water to obtain the binder; the mass ratio of the emulsifier, initiator, deionized water, modified methacrylate, butyl acrylate, acrylic acid, and hydroxypropyl acrylate is 4:1.5:80:20:25:5:21;

[0042] S4. Take the binder, pigment phthalocyanine blue, defoamer BYK-021, dispersant TEGO Dispers 752W, thickener ACRYSOL ASE-60, wetting agent BYK346, leveling agent BYK-333, lightfastness factor, antioxidant 1010, film-forming aid propylene glycol methyl ether acetate, and deionized water, mix them, and after shearing and homogenization, adjust the pH to 9 with 0.1 mol / L ammonia water to obtain the lightfast water-based ink for special paper printing; the mass ratio of the binder, pigment, defoamer, dispersant, thickener, wetting agent, leveling agent, lightfastness factor, antioxidant, film-forming aid, and deionized water is 50:12:1.5:0.5:0.3:4:2:6:1.5:2:40;

[0043] The method for preparing the sun protection factor includes the following steps:

[0044] A1. Take nano-calcium carbonate, anhydrous ethanol, and deionized water, mix them, and ultrasonically disperse them for 15 minutes to obtain material A; the ratio of nano-calcium carbonate, anhydrous ethanol, and deionized water is 1.1g:11mL:1.5mL.

[0045] A2. Mix zinc nitrate hexahydrate, anhydrous ethanol, and deionized water, and stir for 25 minutes to obtain material B; the ratio of zinc nitrate hexahydrate, anhydrous ethanol, and deionized water is 0.45g:5mL:15mL.

[0046] A3. Add material B dropwise to material A under water bath heating and stirring at 45℃, age for 1.5h, put into 100mL hydrothermal crystallization kettle, hydrothermally treat in oven at 120℃ for 4h, and dry at vacuum degree 25Pa and temperature -20℃ for 15h to obtain nano zinc oxide coated calcium carbonate powder.

[0047] A4. Disperse the nano-zinc oxide-coated calcium carbonate powder in anhydrous ethanol, add 3-isocyanate-propyltrimethoxysilane, heat and stir in a water bath at 55°C for 3 hours, filter, wash the solid phase three times with deionized water, disperse it again in deionized water, add silver nitrate solution and continue stirring for 15 minutes, add reducing agent, age for 10 hours, filter, wash the solid phase three times with deionized water, and dry at 105°C for 9 hours to obtain the sun-resistant factor; the ratio of nano-zinc oxide-coated calcium carbonate powder, anhydrous ethanol, 3-isocyanate-propyltrimethoxysilane, deionized water for dispersion, silver nitrate solution, and reducing agent is 1.1g:20mL:1.1mL:50mL:12mL:15mL; the concentration of the silver nitrate solution is 0.1mol / L; the reducing agent is a sodium citrate solution with a concentration of 0.2mol / L.

[0048] Example 3

[0049] A method for preparing a lightfast water-based ink for printing on special paper includes the following steps:

[0050] S1. Under a nitrogen atmosphere, maleic rosin, polyethylene glycol 200, and stannous oxalate were mixed and stirred at 245°C for 5 hours. The mixture was then evacuated to a vacuum of -0.095 MPa and held for 2 hours to remove water and low-boiling-point impurities. The mixture was filtered while hot, and the filtrate was washed three times with a 5% sodium hydroxide solution, followed by washing with deionized water until neutral. After standing and separation, the oil phase was collected to obtain maleic rosin polyethylene glycol ester. The mass ratio of maleic rosin, polyethylene glycol 200, and catalyst was 1.2:2.6:0.04.

[0051] S2. Under a nitrogen atmosphere, the maleic rosin polyethylene glycol ester, p-toluenesulfonic acid, hydroquinone, and toluene were mixed and stirred evenly. Methacrylic acid was added, and the mixture was heated to 110°C, refluxed, and stirred for 3 hours. After cooling to room temperature, a 15% sodium chloride solution was added, stirred, and the mixture was separated. The oil layer was taken and the pH was adjusted to neutral with a 5% sodium hydroxide solution. The mixture was washed with water, and the aqueous layer was separated. The oil phase was dried overnight with anhydrous sodium sulfate, filtered, and the oil phase was separated. Toluene was removed by vacuum distillation at 60°C and a vacuum degree of 5 kPa to obtain modified methacrylic acid ester. The mass ratio of the maleic rosin polyethylene glycol ester, p-toluenesulfonic acid, hydroquinone, toluene, and methacrylic acid was 1:0.018:0.006:40:0.15.

[0052] S3. Mix emulsifier Tween 85, initiator potassium persulfate, and deionized water, stir until homogeneous, add the modified methacrylate, butyl acrylate, acrylic acid, and hydroxypropyl acrylate, stir until homogeneous, heat to 82℃ and stir for 4 hours, heat to 88℃ and hold for 3 hours, cool and discharge, adjust the pH to 8 with 0.1mol / L ammonia water to obtain the binder; the mass ratio of the emulsifier, initiator, deionized water, modified methacrylate, butyl acrylate, acrylic acid, and hydroxypropyl acrylate is 5:2:80:25:30:6:24;

[0053] S4. Take the binder, pigment phthalocyanine blue, defoamer BYK-021, dispersant TEGO Dispers 752W, thickener ACRYSOL ASE-60, wetting agent BYK346, leveling agent BYK-333, lightfastness factor, antioxidant 1010, film-forming aid propylene glycol methyl ether acetate, and deionized water, mix them, and after shearing and homogenization, adjust the pH to 9 with 0.1 mol / L ammonia water to obtain the lightfast water-based ink for special paper printing; the mass ratio of the binder, pigment, defoamer, dispersant, thickener, wetting agent, leveling agent, lightfastness factor, antioxidant, film-forming aid, and deionized water is 60:15:2:0.6:0.4:5:3:8:2:3:45;

[0054] The method for preparing the sun protection factor includes the following steps:

[0055] A1. Take nano-calcium carbonate, anhydrous ethanol, and deionized water, mix them, and ultrasonically disperse them for 10-20 minutes to obtain material A; the ratio of nano-calcium carbonate, anhydrous ethanol, and deionized water is 1.2g:12mL:2mL;

[0056] A2. Mix zinc nitrate hexahydrate, anhydrous ethanol, and deionized water, and stir for 30 minutes to obtain material B; the ratio of zinc nitrate hexahydrate, anhydrous ethanol, and deionized water is 0.5g:5mL:20mL.

[0057] A3. Add material B dropwise to material A under water bath heating and stirring at 45℃, age for 2 hours, pack into 100mL hydrothermal crystallization kettle, hydrothermally treat in 120℃ oven for 5 hours, and dry at vacuum degree 30Pa and temperature -20℃ for 20 hours to obtain nano zinc oxide coated calcium carbonate powder.

[0058] A4. Disperse the nano-zinc oxide-coated calcium carbonate powder in anhydrous ethanol, add 3-isocyanate-propyltrimethoxysilane, heat and stir in a water bath at 60°C for 4 hours, filter, wash the solid phase three times with deionized water, disperse it again in deionized water, add silver nitrate solution and continue stirring for 20 minutes, add reducing agent, age for 12 hours, filter, wash the solid phase three times with deionized water, and dry at 105°C for 10 hours to obtain the sun-resistant factor; the ratio of nano-zinc oxide-coated calcium carbonate powder, anhydrous ethanol, 3-isocyanate-propyltrimethoxysilane, deionized water for dispersion, silver nitrate solution, and reducing agent is 1.2g:20mL:1.2mL:50mL:15mL:15mL; the concentration of the silver nitrate solution is 0.1mol / L; the reducing agent is a sodium citrate solution with a concentration of 0.2mol / L.

[0059] Comparative Example 1

[0060] The difference from Example 2 is that the preparation method of the sun-resistant factor includes the following steps:

[0061] A1. Take nano-calcium carbonate, anhydrous ethanol, and deionized water, mix them, and ultrasonically disperse them for 15 minutes to obtain material A; the ratio of nano-calcium carbonate, anhydrous ethanol, and deionized water is 1.1g:11mL:1.5mL.

[0062] A2. Mix zinc nitrate hexahydrate, anhydrous ethanol, and deionized water, and stir for 25 minutes to obtain material B; the ratio of zinc nitrate hexahydrate, anhydrous ethanol, and deionized water is 0.45g:5mL:15mL.

[0063] A3. Add material B dropwise to material A under water bath heating and stirring at 45℃, age for 1.5h, put into 100mL hydrothermal crystallization kettle, hydrothermally treat in 120℃ oven for 4h, and dry at vacuum degree 25Pa and temperature -20℃ for 15h to obtain nano zinc oxide coated calcium carbonate powder, which is the sun-resistant factor.

[0064] Comparative Example 2

[0065] The difference from Example 2 is that no sun protection factor is added.

[0066] Comparative Example 3

[0067] The difference from Example 2 is that,

[0068] A method for preparing a lightfast water-based ink for printing on special paper includes the following steps:

[0069] S1. Mix emulsifier Tween 85, initiator potassium persulfate, and deionized water, stir until homogeneous, add methacrylate, butyl acrylate, acrylic acid, and hydroxypropyl acrylate, stir until homogeneous, heat to 82℃ and stir for 3.5h, heat to 88℃ and hold for 2.5h, cool and discharge, adjust pH to 8 with 0.1mol / L ammonia water to obtain the binder; the mass ratio of emulsifier, initiator, deionized water, methacrylate, butyl acrylate, acrylic acid, and hydroxypropyl acrylate is 4:1.5:80:20:25:5:21;

[0070] S2. Take the binder, pigment phthalocyanine blue, defoamer BYK-021, dispersant TEGO Dispers 752W, thickener ACRYSOL ASE-60, wetting agent BYK346, leveling agent BYK-333, lightfastness factor, antioxidant 1010, film-forming aid propylene glycol methyl ether acetate, and deionized water, mix them, and after shearing and homogenization, adjust the pH to 9 with 0.1 mol / L ammonia water to obtain the lightfast water-based ink for special paper printing; the mass ratio of the binder, pigment, defoamer, dispersant, thickener, wetting agent, leveling agent, lightfastness factor, antioxidant, film-forming aid, and deionized water is 50:12:1.5:0.5:0.3:4:2:6:1.5:2:40.

[0071] Performance testing

[0072] The water-based inks prepared in Examples 1-3 and Comparative Examples 1-3 were printed onto hot stamping paper substrates (size 10cm×10cm, film thickness 35μm) by gravure printing and dried with hot air at 60℃ for 5h to obtain test samples.

[0073] The above test samples were subjected to sun resistance tests according to standard GB / T 22771-2008; and adhesion tests were conducted according to standard GB / T9286-2021.

[0074] The test results are shown in Table 1 below:

[0075] Table 1

[0076]

[0077] As shown in Table 1, the water-based inks prepared in Examples 1-3 of this application have good sun resistance.

[0078] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A method for preparing a lightfast water-based ink for printing on special paper, characterized in that, Includes the following steps: S1. Modified methacrylate is obtained by esterification reaction of maleic rosin polyethylene glycol ester and methacrylic acid. S2. Take the emulsifier, initiator and deionized water and mix them evenly. Add the modified methacrylate, butyl acrylate, acrylic acid and hydroxypropyl acrylate and stir evenly. Heat to 82°C and stir for 3-4 hours. Heat to 88°C and keep warm for 2-3 hours. Adjust the pH to 7-8 to obtain the binder. S3. Take the binder, pigment, defoamer, dispersant, thickener, wetting agent, leveling agent, sun-resistant factor, antioxidant, film-forming aid, and deionized water, mix and cut evenly, and adjust the pH to 8-9 to obtain the sun-resistant water-based ink for special paper printing. The sun-resistant factor is nano-silver-doped zinc oxide coated calcium carbonate powder.

2. The method for preparing a lightfast water-based ink for printing on special paper according to claim 1, characterized in that, In step S2, the mass ratio of the emulsifier, initiator, deionized water, modified methacrylate, butyl acrylate, acrylic acid, and hydroxypropyl acrylate is 3-5:1-2:80:15-25:20-30:4-6:18-24.

3. The method for preparing a lightfast water-based ink for printing on special paper according to claim 1, characterized in that, In step S3, the mass ratio of the binder, pigment, defoamer, dispersant, thickener, wetting agent, leveling agent, sun-resistant agent, antioxidant, film-forming aid, and deionized water is 40-60:10-15:1-2:0.4-0.6:0.2-0.4:3-5:1-3:4-8:1-2:1-3:35-45.

4. The method for preparing a lightfast water-based ink for printing on special paper according to claim 1, characterized in that, The method for preparing the sun protection factor includes the following steps: A1. Take nano calcium carbonate, anhydrous ethanol and deionized water, mix them, and ultrasonically disperse them for 10-20 minutes to obtain material A; A2. Mix zinc nitrate hexahydrate, anhydrous ethanol, and deionized water, and stir for 20-30 minutes to obtain material B. A3. Add material B dropwise to material A under water bath heating and stirring at 45℃, age for 1-2 hours, put into 100mL hydrothermal crystallization kettle, hydrothermally treat in 120℃ oven for 3-5 hours, and dry at vacuum degree 20-30Pa and temperature -20℃ for 10-20 hours to obtain nano zinc oxide coated calcium carbonate powder. A4. Disperse the nano zinc oxide-coated calcium carbonate powder in anhydrous ethanol, add 3-isocyanate-propyltrimethoxysilane, heat and stir in a water bath at 50-60℃ for 2-4 hours, filter, take the solid phase, wash it three times with deionized water, disperse it again in deionized water, add silver nitrate solution and continue stirring for 10-20 minutes, add reducing agent, age for 8-12 hours, filter, take the solid phase, wash it three times with deionized water, and dry it at 105℃ for 8-10 hours to obtain the sun-resistant factor.

5. The method for preparing a lightfast water-based ink for printing on special paper according to claim 4, characterized in that, In step A1, the ratio of nano-calcium carbonate, anhydrous ethanol, and deionized water is 1-1.2g: 10-12mL: 1-2mL.

6. The method for preparing a lightfast water-based ink for printing on special paper according to claim 4, characterized in that, In step A2, the ratio of zinc nitrate hexahydrate, anhydrous ethanol, and deionized water is 0.4-0.5g: 5mL: 10-20mL.

7. The method for preparing a lightfast water-based ink for printing on special paper according to claim 4, characterized in that, In step A4, the ratio of the nano zinc oxide coated calcium carbonate powder, anhydrous ethanol, 3-isocyanate-propyltrimethoxysilane, deionized water for dispersion, silver nitrate solution, and reducing agent is 1-1.2g:20mL:1-1.2mL:50mL:10-15mL:15mL.

8. The method for preparing a lightfast water-based ink for printing on special paper according to claim 4, characterized in that, In step A4, the concentration of the silver nitrate solution is 0.1 mol / L.

9. The method for preparing a lightfast water-based ink for printing on special paper according to claim 4, characterized in that, In step A4, the reducing agent is a sodium citrate solution with a concentration of 0.2 mol / L.

10. A lightfast water-based ink for printing on special paper, prepared by the method according to any one of claims 1-9.

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