Rosin-based water-based antibacterial ink and preparation process thereof

Abstract

The invention discloses rosin-based water-based antibacterial ink and a preparation process thereof, and belongs to the technical field of ink. The rosin-based water-based antibacterial ink is prepared from the following components in percentage by weight: 15 to 20 percent of water-based heat-resistant resin, 25 to 30 percent of composite pigment, 2 to 3 percent of green antibacterial agent, 6 to 8 percent of additive and 40 to 50 percent of deionized water, the water-based heat-resistant resin is obtained by polymerizing rosin modified resin, an emulsifier and acrylate, the composite pigment is a polyester carbon black composite material, and the auxiliaries comprise a dispersing agent, a thickening agent, a defoaming agent and a preservative. According to the technical scheme, the environment-friendly development requirement is met, meanwhile, the rosin-based water-based antibacterial ink further has good adhesion performance and antibacterial performance, the antibacterial effect is good, the antibacterial duration time is long, and the rosin-based water-based antibacterial ink can be widely applied to the field of various printed products such as tissue packaging.

Description

Technical Field

[0001] The invention relates to a rosin-based water-based antibacterial ink and a preparation process thereof, belonging to the technical field of inks. Background Art

[0002] Water-based ink is an ink made with water as solvent, which can be referred to as water-based ink. The emission of volatile organic compounds in water-based ink is zero or close to zero. It has the green characteristics of being environmentally friendly, non-toxic, energy-saving, and reducing emissions. It also has the advantages of fast drying, excellent water resistance, acid and alkali resistance, and wear resistance, simple operation during the printing process, and the ability to print bright and high-gloss colors. It is a new trend in the development of inks.

[0003] The main components of water-based ink are binders, pigments, water and additives. Binders are also called the "heart" of water-based inks, which directly determine the performance and quality of water-based inks. The main functions of binders are: connecting pigment particles so that the pigments can be better dispersed and spread, giving the ink a certain fluidity and making the ink flow evenly and continuously; providing good adhesion to the printing plate or substrate so that the ink can form a uniform film after printing; improving the specific properties of the ink, such as water resistance; and determining the drying ability of the ink and various printing adaptability. The binder of water-soluble inks is often a water-soluble resin. At present, the most studied ones at home and abroad are modified rosin water-soluble resins and polyacrylic acid water-soluble resins.

[0004] However, most of the current water-based inks use a binder to mix directly with the pigment, during which various additives are added. The binder has poor interaction with the pigment in terms of dispersion, wetting, bonding and protection. In addition, there is still room for improvement in the water-based ink's advantages of being both inexpensive and antibacterial. Summary of the invention

[0005] 1. Technical issues to be resolved

[0006] The technical problem to be solved by the present invention is to solve the problem that the existing water-based ink preparation and its printing performance and antibacterial function do not meet the demand.

[0007] (II) Technical solution

[0008] In order to solve the above technical problems, the present invention provides a rosin-based water-based antibacterial ink, which comprises the following components by weight percentage:

[0009] (1) 15-20% water-based heat-resistant resin (such as 15%, 16%, 18%, 20%), 25-30% composite pigment (such as 25%, 26%, 28%, 30%), 2-3% green antibacterial agent (such as 2%, 2.5%, 3%), 6-8% auxiliary agent (such as 6%, 6.5%, 7%, 8%) and 40%-50% deionized water (such as 40%, 42%, 46%, 48%); the water-based heat-resistant resin is obtained by polymerization of rosin-modified resin, emulsifier and acrylate, the composite pigment is a polyester carbon black composite, and the auxiliary agent includes a dispersant, a thickener, a defoaming agent and a preservative;

[0010] or;

[0011] (2) 40-50% composite material (such as 40%, 42%, 44%, 46%, 48%, 50%), 2-3% green antibacterial agent, 6-8% auxiliary agent and 40%-50% deionized water; the composite material is a composite material formed by chemically cross-linking a water-based heat-resistant resin and carbon black, the water-based heat-resistant resin is obtained by polymerizing rosin-modified resin, emulsifier and acrylate, and the auxiliary agent includes a dispersant, a thickener, a defoaming agent and a preservative.

[0012] Furthermore, it includes the following components by weight percentage: 18% water-based heat-resistant resin, 30% composite pigment, 2% green antibacterial agent, 6.5% auxiliary agent and 43.5% deionized water, wherein the auxiliary agent includes 3% dispersant, 2% thickener, 1% defoamer and 0.5% preservative.

[0013] Furthermore, the rosin modified resin is obtained by esterification reaction of rosin acrylate and pentaerythritol, and the rosin acrylate is obtained by addition reaction of refined rosin and acrylic acid.

[0014] Furthermore, the composite pigment is prepared by chemically cross-linking polyester resin and carbon black.

[0015] Furthermore, the green antibacterial agent includes at least one of nano titanium dioxide, nano silicon dioxide-loaded silver, nano zinc oxide and nano silver.

[0016] Furthermore, the dispersant includes at least one of polyvinyl pyrrolidone, polyacrylic acid, sodium lauryl sulfate, quaternized fatty alcohol and a silane coupling agent.

[0017] Furthermore, the thickener includes at least one of hydroxyethyl cellulose, methyl cellulose, polyacrylic acid and sodium alginate.

[0018] Furthermore, the defoaming agent includes at least one of polydimethylsilicone oil, polyoxyethylene octyl ether and white oil.

[0019] Furthermore, the preservative includes at least one of sodium benzoate, potassium sorbate, ethanol and phenoxyethanol.

[0020] The present invention also provides a preparation process of a rosin-based water-based antibacterial ink, which comprises the following steps:

[0021] S1. Pretreatment: Heat deionized water and water-based heat-resistant resin to 40-50°C, then mix and stir until completely dissolved to obtain a pretreatment solution;

[0022] S2. Pigment dispersion: Mix the composite pigment and dispersant and stir evenly using a high-speed mixer;

[0023] S3. Grinding base ink: Add the mixed composite pigment and dispersant to the pretreatment solution, use a grinder, add the Sano zirconium oxide beads, and grind for 2-3 hours; during the grinding process, gradually add the green antibacterial agent;

[0024] S4 mixing and stirring: The ground base ink was stirred using a magnetic stirrer for 1 hour; during the stirring process, a thickener, a defoamer and a preservative were gradually added;

[0025] S5. Filtration: Filter the prepared water-based antibacterial ink through a filter;

[0026] S6. Performance testing and packaging: The prepared water-based antibacterial ink is subjected to performance tests, including adhesion strength, water resistance, light resistance, antibacterial effect and drying speed, and then the ink is placed in a clean container and sealed for storage.

[0027] (III) Beneficial effects

[0028] The above technical solution of the present invention has the following advantages:

[0029] The present invention can prepare a water-based antibacterial ink with excellent printing performance and antibacterial function, which is suitable for various printing occasions. The rosin-based water-based antibacterial ink of the present invention utilizes the environmental protection performance of rosin-modified water-based resin, combines the antibacterial properties of nano-silver and nano-silicon dioxide, and is suitable for the packaging printing field that requires high hygiene standards and high adhesion. It is not only environmentally friendly, but also has good antibacterial properties.

[0030] The present invention uses polyester resin and carbon black to compound and then mix with water-based heat-resistant resin to prepare water-based ink, which can also bring the following benefits:

[0031] 1. Improvement of comprehensive performance: The compound of polyester resin and carbon black can form a material with excellent mechanical properties. When this composite material is combined with water-based heat-resistant resin, it can comprehensively improve the heat resistance, wear resistance, impact resistance and chemical corrosion resistance of water-based ink.

[0032] 2. Enhance pigment dispersibility: The addition of polyester resin helps to improve the dispersibility of carbon black pigment in water-based ink, thereby improving the color uniformity and stability of the ink, reducing pigment agglomeration, and ensuring printing quality.

[0033] 3. Optimize drying performance: Certain specific functional groups of polyester resin can react with functional groups in water-based heat-resistant resin, thereby accelerating the drying speed of ink and improving production efficiency.

[0034] 4. Improve weather resistance and durability: Carbon black has a good UV shielding effect. Combined with the weather resistance of polyester resin, it can improve the weather resistance and long-term durability of water-based inks, making them suitable for harsh environments such as outdoor.

[0035] 5. Improve adhesion and interlayer bonding: Polyester resin can enhance the adhesion of ink to various substrates, while improving the bonding between coatings to prevent interlayer peeling.

[0036] 6. Improved processability and applicability: The composite of polyester resin and water-based heat-resistant resin can provide better processability, such as leveling, screen printing performance, etc., making the ink easier to operate and suitable for a variety of printing methods.

[0037] 7. Increase environmental performance: Use polyester resin and water-based heat-resistant resin to replace traditional organic solvent-based resin, reduce VOC emissions, reduce the impact on the environment, and meet the requirements of green production and environmental protection.

[0038] 8. Broaden the scope of application: Since the performance of water-based inks has been comprehensively improved, their application scope can be broadened to meet more special printing needs, such as food packaging, high-end decorative printing, etc.

[0039] 9. Improve economic benefits: The combined use of polyester resin and carbon black can optimize the cost structure and improve the performance of water-based ink, thereby improving the overall economic benefits.

[0040] The binder of the water-based ink of the present invention has good interactions in multiple aspects such as dispersion, wetting, bonding and protection of the pigment; and has the advantages of being inexpensive and antibacterial.

[0041] In addition to the technical problems solved by the present invention, the technical features of the technical solutions constituted by the present invention, and the advantages brought about by the technical features of these technical solutions described above, other technical features of the present invention and the advantages brought about by these technical features will be further explained in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0043] Figure 1 This is a schematic diagram of the process flow chart of Example 1 of the present invention. DETAILED DESCRIPTION

[0044] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0045] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0046] A rosin-based water-based antibacterial ink comprises the following components by weight percentage:

[0047] 15-20% water-based heat-resistant resin, 25-30% composite pigment, 2-3% green antibacterial agent, 6-8% auxiliary agent and 40%-50% deionized water; the water-based heat-resistant resin is obtained by polymerization of rosin-modified resin, emulsifier and acrylate, the composite pigment is a polyester carbon black composite, and the auxiliary agent includes a dispersant, a thickener, a defoamer and a preservative. One preferred ratio is: 18% water-based heat-resistant resin, 30% composite pigment, 2% green antibacterial agent, 6.5% auxiliary agent and 43.5% deionized water, wherein the auxiliary agent includes 3% dispersant, 2% thickener, 1% defoamer and 0.5% preservative.

[0048] The detailed steps of preparing water-based heat-resistant resin by polymerization of rosin-modified resin, emulsifier and acrylate are as follows:

[0049] 1. Raw material preparation: Select appropriate rosin modified resin, which usually has a high softening point and good thermal stability. Prepare emulsifier, which can be anionic, cationic or non-ionic emulsifier, to stabilize the emulsion.

[0050] 2. Emulsification process: Add emulsifier to the rosin modified resin and stir evenly to ensure that the resin can be effectively emulsified. You can use a high-speed stirrer or emulsion stirrer for emulsification. The emulsification process usually takes 30 minutes to 1 hour.

[0051] 3. Mixing of acrylate monomer: Mix acrylate monomer with emulsified rosin resin. Stir evenly to ensure that the monomer and resin mixture are fully mixed.

[0052] 4. Polymerization: Add initiator to the mixture to start free radical polymerization. Control the polymerization temperature, usually between 70-90°C, and the reaction time is about 2-4 hours. The reaction temperature can be maintained by water bath heating or a constant temperature oven.

[0053] 5. Post-treatment of the emulsion: After the polymerization reaction is completed, the emulsion is cooled to room temperature. The pH value of the emulsion is adjusted to a suitable range, usually between 7-9. An appropriate amount of defoamer and other additives are added to improve the performance of the emulsion.

[0054] The rosin modified resin is obtained by esterification reaction of rosin acrylate and pentaerythritol, and the rosin acrylate is obtained by addition reaction of refined rosin and acrylic acid, as follows:

[0055] 1. Raw materials preparation:

[0056] Rosin: Choose high-purity rosin as raw material.

[0057] Acrylic acid: Choose neat acrylic acid monomer.

[0058] Pentaerythritol: Choose high purity pentaerythritol.

[0059] Catalyst: such as p-toluenesulfonic acid or sulfuric acid.

[0060] Solvent: such as toluene, xylene or ethyl acetate, etc.

[0061] 2. Rosin refining:

[0062] Heat the rosin until it dissolves, usually between 100-150°C.

[0063] Add an appropriate amount of solvent, such as toluene, to help dissolve the rosin.

[0064] Impurities such as resin acids, unsaturated hydrocarbons, etc. are removed by filtration or other separation techniques.

[0065] 3. Preparation of rosin acrylate by addition reaction:

[0066] The refined rosin is heated to the reaction temperature, usually between 80-120°C.

[0067] Add catalyst and stir well.

[0068] Slowly add acrylic acid monomer dropwise, controlling the dropwise addition rate to maintain the reaction temperature.

[0069] Stirring and heating are maintained, and the reaction time is generally several hours, until the reaction is complete.

[0070] 4. Preparation of rosin modified resin by esterification reaction:

[0071] The prepared rosin acrylate is heated to a reaction temperature, usually between 100-150°C.

[0072] Pentaerythritol was added and stirring and heating were continued.

[0073] The reaction temperature and time are controlled, usually for several hours, until the reaction is complete.

[0074] 5. Post-processing:

[0075] After completion of the reaction, the reaction mixture was cooled to room temperature.

[0076] The catalyst and impurities are removed by filtration or centrifugation.

[0077] The solvent is evaporated to obtain a solid rosin-modified resin.

[0078] The detailed steps of preparing the composite pigment by chemically cross-linking polyester resin and carbon black are as follows:

[0079] 1. Raw material preparation: Select appropriate polyester resins, whose molecular structure contains cross-linkable functional groups, such as hydroxyl, carboxyl, amino, etc. Select high-purity carbon black to ensure the quality and stability of the pigment. Select cross-linking agents that match the functional groups of polyester resins, such as isocyanates, epoxy resins, vinyl compounds, etc. Select appropriate solvents, such as alcohols, esters, etc., as needed to dissolve polyester resins and cross-linking agents.

[0080] 2. Pigment dispersion: Mix the carbon black pigment with an appropriate amount of solvent. Use equipment such as a high-speed stirrer or sand mill to disperse the carbon black pigment in the solvent to form a uniform dispersion.

[0081] 3. Dissolving polyester resin: Mix the polyester resin with the solvent and heat to the dissolving temperature, usually between 60-100°C. Stir until the resin is completely dissolved to form a uniform solution.

[0082] 4. Adding crosslinking agent: Add the crosslinking agent to the polyester resin solution and stir to mix evenly. The reaction between the crosslinking agent and the polyester resin usually requires controlling the pH value, temperature, stirring speed and other conditions (conventional technical means can be used).

[0083] 5. Mixing and cross-linking reaction: Mix the carbon black pigment dispersion with the cross-linked polyester resin solution. Continue stirring to allow the pigment particles to fully contact the polyester resin and promote the cross-linking reaction. Control the reaction temperature and time to ensure that the cross-linking reaction is completely carried out (using conventional technical means).

[0084] 6. Post-treatment: After the cross-linking reaction is completed, the mixture is cooled to room temperature, and the unreacted solvent and impurities are removed by filtration or centrifugation. The resulting composite pigment is dried, usually at a temperature of 60-80°C.

[0085] During the entire preparation process, the reaction conditions need to be strictly controlled to ensure that the pigment is fully in contact with the polyester resin and the cross-linking reaction is completely carried out. In addition, the selection of suitable solvents and cross-linking agents also has an important influence on the performance of the final product. By optimizing the preparation process, composite pigments with excellent performance can be prepared.

[0086] In addition to carbon black, other conventional pigments such as zinc oxide, iron oxide, etc. can also be used for compounding.

[0087] The green antibacterial agent includes at least one of nano titanium dioxide, nano silicon dioxide silver, nano zinc oxide and nano silver. The dispersant includes at least one of polyvinyl pyrrolidone, polyacrylic acid, sodium lauryl sulfate, quaternized fatty alcohol and silane coupling agent. The thickener includes at least one of hydroxyethyl cellulose, methyl cellulose, polyacrylic acid and sodium alginate. The defoamer includes at least one of polydimethyl silicone oil, polyoxyethylene octyl ether and white oil. The preservative includes at least one of sodium benzoate, potassium sorbate, ethanol and phenoxyethanol.

[0088] The preparation process of the above-mentioned rosin-based water-based antibacterial ink comprises the following steps:

[0089] S1. Pretreatment: Heat deionized water and water-based heat-resistant resin to 40-50°C, then mix the two and stir at a low speed until they are completely dissolved to obtain a pretreatment solution; heat deionized water to 40-50°C to increase solubility and dispersibility; heat rosin-modified water-based resin to 50°C to reduce viscosity for easy mixing.

[0090] S2. Pigment dispersion: Mix the composite pigment with the dispersant and stir evenly using a high-speed mixer to prevent the pigment from agglomerating;

[0091] S3. Grinding base ink: Add the mixed composite pigment and dispersant to the pretreatment solution, use a high-speed grinding and dispersing device (grinder), add the Sano zirconium oxide beads, and grind for 2-3 hours to ensure that the pigment particles are fully and evenly dispersed and reach the required fineness; during the grinding process, gradually add the green antibacterial agent, and at the same time, use an antibacterial agent dispersant to help it disperse and ensure that it is evenly dispersed;

[0092] S4. Mixing and stirring: The ground base ink is stirred for 1 hour using a magnetic stirrer to ensure the stability of the ink quality; during the stirring process, a thickener, a defoamer and a preservative are gradually added, and the viscosity of the ink is adjusted by the thickener to make it suitable for use in printing machinery, and the defoamer and preservative are used to improve the printing performance and storage stability of the ink;

[0093] S5. Filtration: filtering the prepared water-based antibacterial ink through a fine mesh filter to remove impurities and undispersed particles;

[0094] S6. Performance testing and packaging: The prepared water-based antibacterial ink is subjected to performance tests, including adhesion strength, water resistance, antibacterial effect, etc., to ensure that the ink meets the preset quality standards and meets printing and hygiene requirements. The ink is then placed in a clean container and sealed for storage.

[0095] Through the above process, a water-based antibacterial ink with excellent printing performance and antibacterial function can be prepared, which is suitable for various printing occasions. This rosin-based water-based antibacterial ink utilizes the environmental protection performance of rosin-modified water-based resin and combines the antibacterial properties of nano-silver and nano-silicon dioxide. It is not only environmentally friendly, but also has good antibacterial properties.

[0096] In the above-mentioned water-based antibacterial ink formula, the traditional pigment is replaced by a composite pigment, which has a better interaction with the binder, and the various performances of the produced water-based ink are greatly improved. Although it is a simple replacement of ingredients, the method of using a composite pigment has not been proposed, and the effect is significant. For those skilled in the art, the blind spot of being dark under the lamp is creatively proposed by the applicant of this application.

[0097] In addition, the above formula can be further optimized. The applicant has also proposed the following formula: 40-50% composite material, 2-3% green antibacterial agent, 6-8% auxiliary agent and 40%-50% deionized water; the composite material is a composite material formed by chemical cross-linking of water-based heat-resistant resin and carbon black, and the water-based heat-resistant resin is obtained by polymerization of rosin-modified resin, emulsifier and acrylate, and the auxiliary agent includes a dispersant, a thickener, a defoaming agent and a preservative.

[0098] The composite material is a composite material formed by chemically cross-linking a water-based heat-resistant resin and a carbon black pigment. The specific production steps are as follows:

[0099] 1. Raw material preparation: Select a water-based heat-resistant resin with cross-linkable functional groups (same as above), such as a resin containing hydroxyl, carboxyl or amino groups; select a high-purity carbon black pigment to ensure its dispersibility and stability; select a cross-linking agent that matches the functional groups of the water-based heat-resistant resin, such as multifunctional isocyanate, acrylate, etc.; select a dispersant suitable for the water-based system to help disperse the carbon black pigment in the resin; if necessary, select a suitable catalyst to accelerate the cross-linking reaction; select a suitable solvent, such as water, ethanol, etc., to dissolve the resin and cross-linking agent.

[0100] 2. Disperse carbon black pigment: Mix the carbon black pigment with the dispersant, add an appropriate amount of aqueous solvent under stirring to form a uniform carbon black dispersion.

[0101] 3. Dissolve the water-based heat-resistant resin: Add the water-based heat-resistant resin into the aqueous solvent while stirring, and heat it to a suitable temperature (usually 50-80°C) to dissolve it.

[0102] 4. Add cross-linking agent and catalyst: Add the pre-calculated amount of cross-linking agent and catalyst (if used) to the dissolved water-based heat-resistant resin. Stir well to ensure that the cross-linking agent and catalyst are completely dissolved.

[0103] 5. Mixing and cross-linking reaction: Slowly add the carbon black dispersion to the water-based heat-resistant resin solution while continuing to stir. By controlling the temperature and stirring speed, the cross-linking reaction of the carbon black pigment and the water-based heat-resistant resin is promoted. The reaction temperature is usually between 60-80°C, and the reaction time varies depending on the specific resin and cross-linking agent, and may take several hours to a whole day.

[0104] 6. Post-treatment: After the cross-linking reaction is completed, cool the mixture to room temperature. Remove the unreacted pigment and resin by centrifugation, filtration or other separation techniques. Dry the resulting composite pigment in a drying oven, usually at 50-70°C for several hours.

[0105] During the whole process, the following points should be noted: the amount of crosslinker and catalyst added should be strictly controlled to avoid excessive or insufficient reaction; the control of reaction temperature and time is crucial to the completeness of the crosslinking reaction; the dispersibility of carbon black pigment in the resin has a direct impact on the performance of the composite pigment, so appropriate dispersants and stirring technology need to be used.

[0106] Example 1

[0107] Ink composition ratio (by weight percentage): 18% water-based heat-resistant resin, 30% composite pigment, 2% green antibacterial agent (1% nano silver, 1% nano titanium dioxide), 43.5% deionized water, 3% dispersant, 2% thickener, 1% defoamer and 0.5% preservative;

[0108] Preparation process, such as Figure 1 As shown:

[0109] S1. Pretreatment: Heat deionized water and water-based heat-resistant resin to 40-50°C, then mix the two and stir at a low speed until they are completely dissolved to obtain a pretreatment solution; heat deionized water to 40-50°C to increase solubility and dispersibility; heat rosin-modified water-based resin to 50°C to reduce viscosity for easy mixing.

[0110] S2. Pigment dispersion: Mix the composite pigment with the dispersant and stir evenly using a high-speed mixer to prevent the pigment from agglomerating;

[0111] S3. Grinding base ink: Add the mixed composite pigment and dispersant to the pretreatment solution, use a high-speed grinding and dispersing device (grinder), add the Sano zirconium oxide beads, and grind for 2-3 hours to ensure that the pigment particles are fully and evenly dispersed and reach the required fineness; during the grinding process, gradually add the green antibacterial agent, and at the same time, use an antibacterial agent dispersant to help it disperse and ensure that it is evenly dispersed;

[0112] S4. Mixing and stirring: The ground base ink is stirred for 1 hour using a magnetic stirrer to ensure the stability of the ink quality; during the stirring process, a thickener, a defoamer and a preservative are gradually added, and the viscosity of the ink is adjusted by the thickener to make it suitable for use in printing machinery, and the defoamer and preservative are used to improve the printing performance and storage stability of the ink;

[0113] S5. Filtration: filtering the prepared water-based antibacterial ink through a fine mesh filter to remove impurities and undispersed particles;

[0114] S6. Performance testing and packaging: The prepared water-based antibacterial ink is subjected to performance tests, including adhesion strength, water resistance, antibacterial effect, etc., to ensure that the ink meets the preset quality standards and meets printing and hygiene requirements. The ink is then placed in a clean container and sealed for storage.

[0115] Example 2

[0116] The ink composition ratio (by weight percentage) is: 15% water-based heat-resistant resin, 30% composite pigment, 2% green antibacterial agent, 46.5% deionized water, 3% dispersant, 2% thickener, 1% defoamer and 0.5% preservative.

[0117] The preparation process is the same as that of Example 1.

[0118] Example 3

[0119] Ink composition ratio (by weight percentage): 45% compound (a compound formed by chemical crosslinking of water-based heat-resistant resin and carbon black), 2% green antibacterial agent, 46.5% deionized water, 3% dispersant, 2% thickener, 1% defoamer and 0.5% preservative.

[0120] S1. Pretreatment: Heat deionized water to 40-50°C;

[0121] S2. Pigment dispersion: Mix the composite material with the dispersant and stir evenly using a high-speed mixer to prevent the pigment from agglomerating;

[0122] S3. Grinding base ink: Add the mixed composite material and dispersant into heated deionized water, use high-speed grinding and dispersing equipment (grinder), add Sino zirconium oxide beads, and grind for 2-3 hours to ensure that the pigment particles are fully and evenly dispersed and reach the required fineness; during the grinding process, gradually add green antibacterial agent, and antibacterial agent dispersant can also be used to help it disperse to ensure its uniform dispersion;

[0123] S4. Mixing and stirring: The ground base ink is stirred for 1 hour using a magnetic stirrer to ensure the stability of the ink quality; during the stirring process, a thickener, a defoamer and a preservative are gradually added, and the viscosity of the ink is adjusted by the thickener to make it suitable for use in printing machinery, and the defoamer and preservative are used to improve the printing performance and storage stability of the ink;

[0124] S5. Filtration: filtering the prepared water-based antibacterial ink through a fine mesh filter to remove impurities and undispersed particles;

[0125] S6. Performance testing and packaging: The prepared water-based antibacterial ink is subjected to performance tests, including adhesion strength, water resistance, antibacterial effect, etc., to ensure that the ink meets the preset quality standards and meets printing and hygiene requirements. The ink is then placed in a clean container and sealed for storage.

[0126] Comparative Example 1

[0127] Ink composition ratio (by weight percentage): 18% water-based heat-resistant resin, 30% carbon black, 2% green antibacterial agent (1% nano silver, 1% nano titanium dioxide), 43.5% deionized water, 3% dispersant, 2% thickener, 1% defoamer and 0.5% preservative;

[0128] The preparation process is the same as that of Example 1.

[0129] In order to verify the performance of the water-based antibacterial ink of the present invention, the adhesion fastness, antibacterial performance, antibacterial durability, water resistance and stability of the water-based antibacterial inks in the above three embodiments, one comparative example, and commercially available water-based inks were tested.

[0130] The test results are shown in the following table:

[0131]

[0132] Adhesion fastness test: refer to GB / T 13217.7-2009; the adhesion fastness of the water-based ink obtained in Examples 1-3 of the present invention is more than 97%, and the water-based ink obtained in the present invention has higher adhesion fastness than the commercially available water-based ink; the adhesion fastness of the water-based ink obtained in Comparative Example 1 is much lower than that in Example 1, which shows that the use of polyester carbon black composite pigment is helpful to improve the adhesion fastness of water-based ink. It can be seen from Example 3 that the composite material formed by directly using water-based heat-resistant resin and carbon black chemically cross-linked can also produce water-based ink with excellent adhesion fastness.

[0133] Antibacterial performance test: refer to GB / T 21866-2008; use the film method to make the sample printed with antibacterial water-based ink evenly contact the sample, and after a period of cultivation, detect the number of live bacteria on the sample and calculate the antibacterial rate. The test bacteria are Staphylococcus aureus and Escherichia coli. It can be seen from the above table that the antibacterial grade of the water-based ink of Examples 1-3 is Grade I (antibacterial performance ≥99%, antibacterial durability ≥95%).

[0134] Water resistance: Place the sample printed with water-based ink in a 55°C oven for 10-15 minutes, wet a paper towel with clean water, lift it up just enough to stop water from dripping, wipe the sample back and forth 5 times with the wet paper towel, and observe whether there is any color on the paper towel. As can be seen from the table above, when testing the water-based ink of Examples 1-3, the wet paper towel wiped back and forth 5 times without fading.

[0135] It can also be seen that the adhesion of the water-based ink obtained in Examples 1-3 is still not less than 92% after being placed for half a year, and the storage stability is high; the adhesion of the water-based ink obtained in Comparative Example 1 is significantly lower than that of Example 1 after being placed for half a year, which shows that the use of polyester carbon black composite pigment has a significant benefit effect on improving the stability of water-based ink. It can be seen from Example 3 that the composite material formed by directly using water-based heat-resistant resin and carbon black chemically cross-linked can also produce water-based ink with excellent stability, which helps to improve the stability of water-based ink.

[0136] In summary, compared with the water-based antibacterial ink in comparative example 1 and the commercially available water-based ink, the water-based antibacterial ink obtained according to Examples 1-3 of the present invention has effectively improved water resistance, stability and adhesion fastness, and has excellent antibacterial effect. The technical solution of the present invention meets the development requirements of green environmental protection, and the water-based antibacterial ink also has good adhesion and antibacterial properties, good antibacterial effect, long antibacterial duration, and can be widely used in various printed products.

[0137] The specific implementation modes of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above implementation modes, and various changes can be made within the knowledge scope of ordinary technicians in this field without departing from the purpose of the present invention.

Claims

1. A rosin-based water-based antibacterial ink, characterized in that: The following components are included by weight percentage: 15-20% water-based heat-resistant resin, 25-30% composite pigment, 2-3% green antibacterial agent, 6-8% additives and 40%-50% deionized water; the water-based heat-resistant resin is obtained by polymerization of rosin-modified resin, emulsifier and acrylate, the composite pigment is a polyester carbon black composite, and the additives include a dispersant, a thickener, a defoamer and a preservative; or; 40-50% composite material, 2-3% green antibacterial agent, 6-8% auxiliary agent and 40%-50% deionized water; the composite material is a composite material formed by chemically cross-linking water-based heat-resistant resin and carbon black, the water-based heat-resistant resin is obtained by polymerizing rosin-modified resin, emulsifier and acrylate, and the auxiliary agent includes a dispersant, a thickener, a defoaming agent and a preservative.

2. The rosin-based water-based antibacterial ink according to claim 1, characterized in that: The composition comprises the following components by weight percentage: 18% water-based heat-resistant resin, 30% composite pigment, 2% green antibacterial agent, 6.5% auxiliary agent and 43.5% deionized water, wherein the auxiliary agent comprises 3% dispersant, 2% thickener, 1% defoamer and 0.5% preservative.

3. The rosin-based water-based antibacterial ink according to claim 2, characterized in that: The rosin modified resin is obtained by esterification reaction of rosin acrylate and pentaerythritol, and the rosin acrylate is obtained by addition reaction of refined rosin and acrylic acid.

4. The rosin-based water-based antibacterial ink according to claim 3, characterized in that: The composite pigment is prepared by chemically cross-linking polyester resin and carbon black.

5. The rosin-based water-based antibacterial ink according to claim 4, characterized in that: The green antibacterial agent comprises at least one of nano titanium dioxide, nano silicon dioxide loaded with silver, nano zinc oxide and nano silver.

6. The rosin-based water-based antibacterial ink according to claim 5, characterized in that: The dispersant includes at least one of polyvinyl pyrrolidone, polyacrylic acid, sodium lauryl sulfate, quaternized fatty alcohol and a silane coupling agent.

7. The rosin-based water-based antibacterial ink according to claim 6, characterized in that: The thickener includes at least one of hydroxyethyl cellulose, methyl cellulose, polyacrylic acid and sodium alginate.

8. The rosin-based water-based antibacterial ink according to claim 7, characterized in that: The defoaming agent includes at least one of polydimethylsilicone oil, polyoxyethylene octyl ether and white oil.

9. The rosin-based water-based antibacterial ink according to claim 8, characterized in that: The preservative includes at least one of sodium benzoate, potassium sorbate, ethanol and phenoxyethanol.

10. A process for preparing a rosin-based water-based antibacterial ink according to any one of claims 1 to 9, characterized in that: The following steps are involved: S1. Pretreatment: Heat deionized water and water-based heat-resistant resin to 40-50°C, then mix the two and stir at a low speed until they are completely dissolved to obtain a pretreatment solution; S2. Pigment dispersion: Mix the composite pigment and dispersant and stir evenly using a high-speed mixer; S3. Grinding base ink: Add the mixed composite pigment and dispersant to the pretreatment solution, use a grinder, add the Sano zirconium oxide beads, and grind for 2-3 hours; during the grinding process, gradually add the green antibacterial agent; S4. Mixing and stirring: The ground base ink was stirred using a magnetic stirrer for 1 hour; During the stirring process, gradually add thickener, defoamer and preservative; S5. Filtration: Filter the prepared water-based antibacterial ink through a filter; S6. Performance testing and packaging: The prepared water-based antibacterial ink is subjected to performance tests, including adhesion strength, water resistance, light resistance, antibacterial effect and drying speed, and then the ink is placed in a clean container and sealed for storage.

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