Ink for printer and preparation method thereof

Abstract

The invention discloses printer ink and a preparation method thereof, and belongs to the technical field of printer ink. Comprising the following raw materials in parts by mass: 5-7 parts of pigment, 2-4 parts of a quick-drying agent, 1.5-3 parts of a surfactant, 40-50 parts of waterborne polyurethane resin, 1-3 parts of a flatting agent, 4-12 parts of an anti-aging aid and 120-160 parts of water. Through the self-made anti-aging additive, the photooxidation resistance of the ink is remarkably improved; a drying accelerating agent is added, so that the drying speed of the ink on the medium is accelerated; water is used as a main dispersion medium, so that the harm to the environment and operators is reduced, and the green development trend is met. In conclusion, the environment-friendly advantage of the water-based ink is kept, meanwhile, the defects that traditional water-based ink is slow in drying and prone to fading are overcome, the water-based ink meets the printing requirements of families, offices and outdoor scenes, and the water-based ink has important application value in the technical field of printer ink.

Description

Technical Field

[0001] The present invention belongs to the technical field of printer inks, and specifically relates to an ink for printers and a preparation method thereof. Background Art

[0002] With the popularization of computers, printers have been widely used. Compared with laser printers, such printers have a lower price, and compared with dot matrix printers, they have less noise, and can obtain high-quality color graphics and image outputs. They have been increasingly accepted by the majority of users, and the penetration rate has also been increasing day by day, making home and office affairs more convenient, efficient, and standardized. Due to the particularity of the inkjet printing method, higher requirements are imposed on the ink for printers.

[0003] Currently, the inks for printers are mainly solvent-based inks, UV curable inks, and water-based pigment inks. Among them, solvent-based inks have bright colors and good water, weather, and scratch resistance, but generally have a strong odor and a high VOC content. They will volatilize into the air during use, which not only poses a potential hazard to the health of operators, but also pollutes the atmospheric environment. UV curable inks have bright colors, are water, weather, and scratch resistant, have a fast drying speed, and almost no VOC emissions. However, the monomers used in them have a strong odor and are skin sensitizing, and at the same time, there are disadvantages such as high energy consumption and high cost. Water-based pigment inks use water as the main dispersion medium, are non-toxic and harmless, produce almost no volatile organic compounds, are beneficial to environmental protection, and have low costs, which is the development trend of inks for printers in the future.

[0004] Although water-based pigment inks are green and environmentally friendly, they are easily oxidized under outdoor light irradiation, will fade rapidly, affecting the color of the ink, and water-based pigment inks have a slow drying speed. These two disadvantages limit the application of water-based pigment inks. Therefore, it is urgent to solve the above problems to meet the higher requirements in the technical field of printer inks. Summary of the Invention

[0005] The purpose of the present invention is to overcome the defects of the prior art and provide an ink for printers and a preparation method thereof.

[0006] The purpose of the present invention can be achieved by the following technical solutions:

[0007] An ink for printers, comprising the following raw materials in parts by mass: 5-7 parts of pigment, 2-4 parts of quick-drying agent, 1.5-3 parts of surfactant, 40-50 parts of water-based polyurethane resin, 1-3 parts of leveling agent, 4-12 parts of anti-aging agent, and 120-160 parts of water.

[0008] As a further technical solution, the quick-drying agent is one of isopropyl alcohol and ethanol.

[0009] As a further technical solution, the surfactant is one of sodium dodecylbenzenesulfonate, fatty alcohol polyoxyethylene ether and octylphenol polyoxyethylene ether.

[0010] The function of adding a quick-drying agent in the present invention is to accelerate the drying of the ink on the medium (such as paper, plastic, etc.), prevent ink bleeding and smudging, and improve the printing clarity and efficiency.

[0011] As a further technical solution, the anti-aging aid is prepared through the following steps:

[0012] Step 1: In a four-necked flask equipped with a constant-pressure dropping funnel, a thermometer, a mechanical stirrer and a reflux condenser, first add pentaerythritol, pyridine and dichloromethane, and in an ice-water bath at 0 °C, stir mechanically to completely dissolve pentaerythritol. Then dissolve phosphorus trichloride in dichloromethane and add it dropwise (dropwise addition rate: 2 drops / second) to the flask using a dropping funnel. During the dropping process, ensure that the temperature ≤ 0 °C. After the dropping is completed, remove the ice bath, slowly raise the temperature to 40 °C, maintain the temperature and reflux for 4 hours. After the reaction is completed, cool to room temperature, filter to remove the pyridine hydrochloride precipitate, distill the filtrate under reduced pressure to remove the solvent, recrystallize the residue with n-hexane, and dry it under vacuum to obtain product A;

[0013] As a further technical solution, in Step 1, the dosage ratio of pentaerythritol, pyridine, dichloromethane, and phosphorus trichloride is 13.6 g: 15.8 g: 120 mL: 27.4 - 28.5 g.

[0014] The reaction principle of Step 1 is: Under the catalysis of pyridine, pentaerythritol and phosphorus trichloride react, and the amount of substance of phosphorus trichloride is twice that of pentaerythritol to make the reaction proceed fully; the reaction formula is as follows:

[0015]

[0016] Step 2: In a three-necked flask equipped with a thermometer, a magnetic stirrer and a condenser, add product A and anhydrous acetonitrile, stir magnetically to dissolve product A, and then add pentamethyldiethanolamine, potassium carbonate and tetrabutylammonium bromide to the flask and continue stirring for 10 - 20 minutes. Pass nitrogen, place the device in an oil bath at 78 °C, and continue the reaction for 6 hours. After the reaction is completed, cool to room temperature, filter, wash the filter residue 3 times with anhydrous acetonitrile, and perform column chromatography separation to obtain product B;

[0017] As a further technical solution, in Step 2, the dosage ratio of product A, anhydrous acetonitrile, pentamethyldiethanolamine, potassium carbonate, and tetrabutylammonium bromide is 26.3 - 28.6 g: 100 mL: 17.1 g: 13.8 g: 1.5 g.

[0018] The reaction principle of Step 2 is as follows: Potassium carbonate acts as an acid-binding agent, and tetrabutylammonium bromide acts as a phase transfer agent to catalyze the reaction between reaction product A and pentamethyldiethanolamine, with product A being slightly in excess; the reaction formula is as follows:

[0019]

[0020] Step 3: Add polyethylene glycol (molecular weight 400), N,N-dimethylformamide, and potassium carbonate into a three-necked flask equipped with a thermometer, a magnetic stirrer, and a condenser. Then heat up to 55 °C and stir for 20 - 30 minutes. After that, add tetrabutylammonium bromide and product B, stir evenly, then heat up to 80 °C and react for 4 hours. After the reaction is completed, cool to room temperature, filter, pour the filtrate into ice water, stir to precipitate the product, perform suction filtration under reduced pressure, wash the solid with cold ether multiple times, and dry it under vacuum to obtain the anti-aging agent.

[0021] As a further technical solution, in Step 3, the dosage ratio of polyethylene glycol, N,N-dimethylformamide, potassium carbonate, tetrabutylammonium bromide, and product B is 40.0 g: 200 mL: 13.8 g: 3.2 g: 39.9 - 41.2 g.

[0022] The reaction principle of Step 2 is as follows: Potassium carbonate acts as an acid-binding agent, and tetrabutylammonium bromide acts as a phase transfer agent to catalyze the nucleophilic substitution reaction between polyethylene glycol and product B to obtain the anti-aging agent.

[0023] The anti-aging agent prepared by the present invention contains hindered amine and phosphite anti-aging groups in its molecule. Among them, the hindered amine, as a light stabilizer, decomposes hydrogen peroxide to generate stable nitroxide radicals, inhibiting the photodegradation of the ink. In addition, the phosphite, as an auxiliary anti-aging group, can decompose the hydroperoxides generated by photoaging in the ink, thereby achieving the purpose of terminating or delaying the oxidative degradation of the ink; the two can play a synergistic effect, greatly improving the anti-photoaging performance of the ink, enabling the ink to be used in outdoor and other scenarios that require exposure to sunlight. Finally, the anti-aging agent also contains a polyethylene glycol hydrophilic molecular chain, making the anti-aging agent more easily dispersed in the water-based ink compared with the anti-aging agents on the market, and enabling its anti-aging performance to be fully exerted.

[0024] The present invention also provides a method for preparing a printer ink, comprising the following steps:

[0025] Step 1: Stir the pigment, quick-drying agent, surfactant, and part of the water evenly in a high-speed shear mixer to obtain a pigment dispersion.

[0026] Step 2: Mix the pigment dispersion obtained in Step 1, waterborne polyurethane resin, leveling agent, anti-aging agent, and the remaining water, stir at a low speed, and after mixing evenly, filter through a 0.2 - 1.0 μm microporous filter membrane to remove large particle impurities to obtain the printer ink.

[0027] As a further technical solution, the partial water is 1 / 4 of the total water consumption.

[0028] As a further technical solution, the rotational speed of the high-speed shearing machine is 3000 - 5000 rpm, and the stirring time is 30 - 60 minutes.

[0029] As a further technical solution, the rotational speed of the low-speed stirring is 200 - 500 rpm, and the stirring time is 15 - 30 minutes.

[0030] Advantages of the present invention:

[0031] 1. By self-making an anti-aging additive (containing hindered amine and phosphite groups), the present invention significantly improves the photo-oxidation resistance of the ink, delays fading, and is applicable to outdoor and other sunlight-irradiated scenarios;

[0032] 2. By adding a quick-drying agent (such as isopropanol or ethanol), the drying speed of the ink on the medium is accelerated, bleeding or smudging is avoided, and the printing clarity and efficiency are improved;

[0033] 3. Using water as the main dispersion medium, the water-based formulation is non-toxic and has low VOC emissions, reducing the harm to the environment and operators, conforming to the trend of green development. Compared with solvent-based inks and UV inks, problems such as high pollution and high energy consumption are avoided;

[0034] 4. Through high-speed shearing and microfiltration processes, it is ensured that the ink particles are fine and uniform, reducing the risk of nozzle clogging;

[0035] In summary, while maintaining the environmental protection advantages of water-based inks, the present invention solves the defects of slow drying and easy fading of traditional water-based inks, is applicable to the printing needs of home, office and outdoor scenarios, and has important application value in the field of printer ink technology. Specific embodiments

[0036] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0037] Embodiment 1

[0038] Prepare an anti-aging additive:

[0039] Step 1: In a four-necked flask equipped with a constant-pressure dropping funnel, a thermometer, a mechanical stirrer, and a reflux condenser, first add 13.6 g of pentaerythritol, 15.8 g of pyridine, and 60 mL of dichloromethane. Place it in an ice-water bath at 0 °C and stir mechanically until the pentaerythritol is completely dissolved. Then dissolve 27.4 g of phosphorus trichloride in 60 mL of dichloromethane and add it dropwise (at a dropping rate of 2 drops / second) to the flask using the dropping funnel. During the dropping process, ensure that the temperature ≤ 0 °C. After the dropping is complete, remove the ice bath and slowly raise the temperature to 40 °C. Maintain the temperature and reflux for 4 hours. After the reaction is completed, cool to room temperature, filter to remove the pyridine hydrochloride precipitate, distill the filtrate under reduced pressure to remove the solvent, recrystallize the residue with n-hexane, and dry it under vacuum to obtain product A;

[0040] Step 2: In a three-necked flask equipped with a thermometer, a magnetic stirrer, and a condenser, add 26.3 g of product A and 100 mL of anhydrous acetonitrile. Stir magnetically to dissolve product A. Subsequently, add 17.1 g of pentamethyldiethanolamine, 13.8 g of potassium carbonate, and 1.5 g of tetrabutylammonium bromide to the flask and continue stirring for 10 minutes. Pass nitrogen gas, place the apparatus in an oil bath at 78 °C, and continue the reaction for 6 hours. After the reaction is completed, cool to room temperature, filter, wash the filter residue 3 times with anhydrous acetonitrile, and perform column chromatography separation (dichloromethane:methanol = 10:1 as the eluent) to obtain product B;

[0041] Step 3: In a three-necked flask equipped with a thermometer, a magnetic stirrer, and a condenser, add 40.0 g of polyethylene glycol (molecular weight 400), 200 mL of N,N-dimethylformamide, and 13.8 g of potassium carbonate. Then raise the temperature to 55 °C and stir for 20 minutes. Then add 3.2 g of tetrabutylammonium bromide and 39.9 g of product B, stir evenly, raise the temperature to 80 °C, and react for 4 hours. After the reaction is completed, cool to room temperature, filter, pour the filtrate into ice water, stir to precipitate the product, filter under reduced pressure, wash the solid with cold ether multiple times, and dry it under vacuum to obtain the anti-aging agent.

[0042] Example 2

[0043] Preparation of anti-aging agent:

[0044] Step 1: In a four-necked flask equipped with a constant pressure dropping funnel, a thermometer, a mechanical stirrer, and a reflux condenser, first add 13.6 g of pentaerythritol, 15.8 g of pyridine, and 60 mL of dichloromethane. Place it in an ice-water bath at 0 °C and stir mechanically until the pentaerythritol is completely dissolved. Then dissolve 28.5 g of phosphorus trichloride in 60 mL of dichloromethane and add it dropwise (at a dropping rate of 2 drops / second) to the flask using the dropping funnel. During the dropping process, ensure that the temperature ≤ 0 °C. After the dropping is completed, remove the ice bath and slowly warm up to 40 °C. Maintain the temperature and reflux for 4 hours. After the reaction is completed, cool to room temperature, filter to remove the pyridine hydrochloride precipitate, distill the filtrate under reduced pressure to remove the solvent, recrystallize the residue with n-hexane, and dry it under vacuum to obtain product A;

[0045] Step 2: In a three-necked flask equipped with a thermometer, a magnetic stirrer, and a condenser, add 28.6 g of product A and 100 mL of anhydrous acetonitrile. Stir magnetically to dissolve product A. Subsequently, add 17.1 g of pentamethyldiethanolamine, 13.8 g of potassium carbonate, and 1.5 g of tetrabutylammonium bromide to the flask and continue stirring for 20 minutes. Pass in nitrogen, place the apparatus in an oil bath at 78 °C, and continue the reaction for 6 hours. After the reaction is completed, cool to room temperature, filter, wash the filter residue 3 times with anhydrous acetonitrile, and perform column chromatography separation (dichloromethane:methanol = 10:1 as the eluent) to obtain product B;

[0046] Step 3: In a three-necked flask equipped with a thermometer, a magnetic stirrer, and a condenser, add 40.0 g of polyethylene glycol (molecular weight 400), 200 mL of N,N-dimethylformamide, and 13.8 g of potassium carbonate. Then warm up to 55 °C and stir for 30 minutes. Then add 3.2 g of tetrabutylammonium bromide and 41.2 g of product B, stir evenly, and warm up to 80 °C for reaction for 4 hours. After the reaction is completed, cool to room temperature, filter, pour the filtrate into ice water, stir to precipitate the product, filter under reduced pressure, wash the solid with cold ether multiple times, and dry it under vacuum to obtain the anti-aging agent.

[0047] Example 3

[0048] Preparation of printer ink:

[0049] Step 1: Weigh 5 g of phthalocyanine blue, 2 g of isopropanol, 1.5 g of sodium dodecylbenzenesulfonate, and 30 g of water. Stir in a high-speed shear mixer at a speed of 3000 rpm for 30 minutes to obtain a pigment dispersion;

[0050] Step 2: Mix the pigment dispersion obtained in Step 1, 40 g of waterborne polyurethane resin, 1 g of leveling agent (BYK-354), 4 g of the anti-aging agent prepared in Example 1, and 90 g of water, stir at a speed of 200 rpm for 15 minutes, mix evenly, and then filter through a 0.2 μm microporous filter membrane to remove large particle impurities to obtain printer ink.

[0051] Example 4

[0052] Prepare ink for printer:

[0053] Step 1: Weigh 6 g of azo red, 3 g of ethanol, 2 g of fatty alcohol polyoxyethylene ether and 35 g of water, and stir in a high-speed shearing machine at a speed of 4000 rpm for 45 minutes to obtain a pigment dispersion;

[0054] Step 2: Mix the pigment dispersion obtained in Step 1, 45 g of waterborne polyurethane resin, 2 g of leveling agent (BYK-354), 8 g of anti-aging aid prepared in Example 2 and 105 g of water, stir at a speed of 400 rpm for 30 minutes, and after mixing evenly, filter with a 0.5 μm microporous filter membrane to remove large particle impurities to obtain ink for printer.

[0055] Example 5

[0056] Prepare ink for printer:

[0057] Step 1: Weigh 7 g of carbon black, 4 g of ethanol, 3 g of octylphenol polyoxyethylene ether and 40 g of water, and stir in a high-speed shearing machine at a speed of 5000 rpm for 60 minutes to obtain a pigment dispersion;

[0058] Step 2: Mix the pigment dispersion obtained in Step 1, 50 g of waterborne polyurethane resin, 3 g of leveling agent (BYK-354), 12 g of anti-aging aid prepared in Example 2 and 120 g of water, stir at a speed of 500 rpm for 30 minutes, and after mixing evenly, filter with a 1.0 μm microporous filter membrane to remove large particle impurities to obtain ink for printer.

[0059] Comparative Example 1

[0060] In the process of preparing Example 5, only replace the anti-aging aid with an equivalent mass of hindered phenol anti-aging agent, and the other steps are the same as those in Example 5 to obtain ink.

[0061] Comparative Example 2

[0062] Use commercially available printer ink.

[0063] For Examples 3, 4, and 5, and Comparative Examples 1 and 2, different test methods are adopted according to different standards for the following performance tests:

[0064] Determine the drying time according to ISO 9117-3 standard;

[0065] After aging the specimen according to the national standard GB / T 1865-2009 "Paints and varnishes - Artificial weathering and exposure to artificial radiation - Filtered xenon-arc radiation", observe whether the specimen is powdered and faded;

[0066]

[0067] As can be seen from the above table, the ink prepared in the embodiments of the present invention has no chalking and fading after the aging test. Therefore, it has excellent anti-aging performance and has important application value in the technical field of printer ink.

[0068] In the description of the specification, the description with reference to terms such as "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in connection 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 does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0069] The above content is only an example and illustration of the present invention. Those skilled in the art of the present technology may make various modifications or supplements to the described specific embodiments or use similar ways to replace them, all of which should fall within the protection scope of the present invention.

Claims

1. An ink for a printer, characterized in that, It comprises raw materials in the following parts by mass: 5 - 7 parts of pigment, 2 - 4 parts of quick - drying agent, 1.5 - 3 parts of surfactant, 40 - 50 parts of waterborne polyurethane resin, 1 - 3 parts of leveling agent, 4 - 12 parts of anti - aging agent, and 120 - 160 parts of water.

2. The ink for a printer according to claim 1, characterized in that, The anti - aging agent is prepared through the following steps: Step 1: Add pentaerythritol, pyridine, and dichloromethane into a flask, and place it in an ice - water bath. After stirring, dissolve phosphorus trichloride in dichloromethane and add it to the flask. Reflux and react at 40 °C for 4 hours. After the reaction is completed, product A is obtained. Step 2: Add product A and anhydrous acetonitrile into a flask. After stirring, add pentamethyldiethanolamine, potassium carbonate, and tetrabutylammonium bromide into the flask. Continue to stir, introduce nitrogen, and react at 78 °C for 6 hours. After the reaction is completed, product B is obtained. Step 3: Add polyethylene glycol, N,N - dimethylformamide, and potassium carbonate into a flask, then heat up to 55 °C. After stirring, add tetrabutylammonium bromide and product B. After stirring, react at 80 °C for 4 hours. After the reaction is completed, the anti - aging agent is obtained.

3. The ink for a printer according to claim 2, characterized in that, In step 1, the mass ratio of pentaerythritol, pyridine, dichloromethane, and phosphorus trichloride is 13.6 g:15.8 g:120 mL:27.4 - 28.5 g.

4. The ink for a printer according to claim 2, characterized in that, In step 2, the mass ratio of product A, anhydrous acetonitrile, pentamethyldiethanolamine, potassium carbonate, and tetrabutylammonium bromide is 26.3 - 28.6 g:100 mL:17.1 g:13.8 g:1.5 g.

5. An ink for a printer according to claim 2, characterized in that, In step 3, the mass ratio of polyethylene glycol, N,N - dimethylformamide, potassium carbonate, tetrabutylammonium bromide, and product B is 40.0 g:200 mL:13.8 g:3.2 g:39.9 - 41.2 g.

6. The ink for a printer according to claim 1, characterized in that, The quick - drying agent is one of isopropanol and ethanol.

7. An ink for a printer according to claim 1, characterized in that, The surfactant is one of sodium dodecylbenzenesulfonate, fatty alcohol polyoxyethylene ether, and octylphenol polyoxyethylene ether.

8. A method for preparing an ink for a printer according to any one of claims 1-7, characterized in that, It comprises the following steps: Step 1: Stir the pigment, quick - drying agent, surfactant, and part of the water evenly in a high - speed shearing machine to obtain a pigment dispersion. Step 2: Mix the pigment dispersion obtained in step 1, waterborne polyurethane resin, leveling agent, anti - aging agent, and the remaining water, stir at a low speed, and after mixing evenly, filter with a 0.2 - 1.0 μm microporous filter membrane to remove large - particle impurities to obtain the printer ink.

9. The preparation method of an ink for a printer according to claim 8, characterized in that, The part of the water is 1 / 4 of the total water consumption.

10. The preparation method of an ink for a printer according to claim 8, wherein, The rotation speed of the high - speed shearing machine is 3000 - 5000 rpm, and the stirring time is 30 - 60 minutes; the rotation speed of the low - speed stirring is 200 - 500 rpm, and the stirring time is 15 - 30 minutes.

Images