Degradable environment-friendly anti-aging UV ink and preparation method thereof

Abstract

The invention belongs to the technical field of UV curing ink, and discloses degradable environment-friendly anti-aging UV ink and a preparation method thereof. The ink mainly comprises 2, 5-furandicarboxylic acid-itaconic acid block hyperbranched polyester acrylate resin, 1, 4-cyclohexanedimethanol diacrylate, tetrahydrofuran acrylate, a 4-hydroxybenzophenone grafted polycaprolactone monoacrylate photoinitiator, a coloring agent and an auxiliary agent. According to the invention, through the matched processes of resin and photoinitiator synthesis, pigment grafting pretreatment, gradient low-temperature prepolymerization and the like, the performance of the ink is synergistically improved, the obtained ink is biodegradable under a composting condition and has excellent aging resistance, the photoinitiator has no migration risk, and the storage stability and printability are good; and the ink can be widely applied to printing scenes with high requirements on environmental protection and use stability, such as food contact packaging and environment-friendly labels.

Description

Technical Field

[0001] This invention belongs to the field of UV curing ink technology, specifically relating to a biodegradable, environmentally friendly, and aging-resistant UV ink and its preparation method. Background Technology

[0002] UV-curable inks, with their characteristics of no volatile organic compound emissions, fast curing speed, and low production energy consumption, have been widely used in various fields such as packaging printing, label printing, and paper decoration. As global environmental regulations continue to escalate, more stringent requirements are being placed on the biodegradability, migration safety, and long-term stability of printing inks in niche applications such as food contact packaging and biodegradable flexible packaging.

[0003] Existing biodegradable UV ink technologies mostly use aliphatic polyester resins as the film-forming matrix. Although they can achieve a certain degree of biodegradation, they generally suffer from a core performance contradiction: the ester bonds in the polyester backbone are easily broken by ultraviolet radiation, resulting in insufficient aging resistance of the ink-cured film, making it difficult to balance stability during use and degradability after disposal; conventionally used small-molecule photoinitiators are prone to migration and precipitation, posing a food contact safety hazard, and cannot form a synergistic degradation effect with the biodegradable matrix.

[0004] Existing technologies mostly employ conventional mixing-grinding ink preparation processes, which often result in uneven pigment dispersion and agglomeration / settling during storage in biodegradable polyester matrices. Furthermore, the inks exhibit high shrinkage rates after curing and insufficient adhesion to the substrate. Currently, the industry lacks a stable technical solution that simultaneously achieves high biodegradability, excellent aging resistance, low migration risk, and good printability, making it difficult to meet the rapidly developing needs of the environmentally friendly packaging industry. Summary of the Invention

[0005] In order to overcome the above-mentioned defects of the prior art, the embodiments of the present invention provide a biodegradable and environmentally friendly aging-resistant UV ink and its preparation method, which solves the problems of existing biodegradable UV inks that are difficult to balance biodegradability and aging resistance, high risk of photoinitiator migration, and insufficient pigment dispersion stability and printability.

[0006] To address the above problems, the present invention provides the following technical solution: A biodegradable, environmentally friendly, and aging-resistant UV ink, comprising the following components by weight: 45-65 parts of 2,5-furandicarboxylic acid-itaconic acid block hyperbranched polyester acrylate resin; 8-15 parts of 1,4-cyclohexanediethanol diacrylate; 7-15 parts of tetrahydrofuran acrylate; 3-8 parts of 4-hydroxybenzophenone-grafted polycaprolactone monoacrylate photoinitiator; 5-18 parts of colorant; 0.2-1 parts of polyether-modified polydimethylsiloxane leveling agent; Polyethylene wax dispersant 0.3-1.5 parts; Antioxidant 0.1-0.5 parts.

[0007] Furthermore, the colorant is any one of rutile titanium dioxide, phthalocyanine blue BGS, or carbon black N330. The selected pigment has no recalcitrant degradable groups, has good compatibility with the biodegradable resin system of this invention, is resistant to ultraviolet radiation, and meets the system's aging resistance requirements.

[0008] Furthermore, the polyether-modified polydimethylsiloxane leveling agent is BYK-333. This leveling agent can reduce the surface tension of the ink system, improve the spreadability of the ink on the substrate, and does not affect the curing and degradation performance of the system.

[0009] Furthermore, the polyethylene wax dispersant is BYK-9076. This dispersant can anchor the surface of pigment particles, reduce the risk of pigment agglomeration, and improve the dispersion stability of pigments in biodegradable resin systems.

[0010] Furthermore, the antioxidant is antioxidant 1010. This antioxidant can capture active free radicals in the system, inhibit ink curing and thermo-oxidative aging during use, and improve the system's weather resistance.

[0011] The present invention relates to a biodegradable, environmentally friendly, and aging-resistant UV ink, which uses 2,5-furandicarboxylic acid-itaconic acid block hyperbranched polyester acrylate resin as the film-forming body, combined with 1,4-cyclohexanediethanol diacrylate and tetrahydrofuran acrylate as reactive diluents, and uses 4-hydroxybenzophenone-grafted polycaprolactone monoacrylate photoinitiator to match the curing requirements of the system. Colorants, leveling agents, dispersants, and antioxidants are added to adjust the ink's performance. After the components are adapted, the ink meets the requirements of biodegradability, aging resistance, and printing applications.

[0012] As a general inventive concept, this invention provides a method for preparing the above-described biodegradable, environmentally friendly, and aging-resistant UV ink, comprising the following steps: S1. Add 1,4-butanediol and itaconic acid to the reactor, start stirring, and control the stirring speed at 200-400 r / min. Add 2,5-furandicarboxylic acid, p-toluenesulfonic acid, and hydroquinone. Purge with nitrogen 2-4 times, and maintain nitrogen protection throughout the process. Raise the temperature to 145-150℃ and hold for pre-dispersion for 30 min. Raise the temperature to 160-170℃ and react for 2.5-3.5 h. Continuously separate the water generated in the reaction using a reflux condenser until the acid value of the system drops to 25-30 mg KOH / g. Maintain the temperature at 160-170℃ and reduce the pressure for 25-35 min under a vacuum of -0.095~-0.1 MPa. n, to obtain a carboxyl-terminated linear block polyester prepolymer; cool the prepolymer to 130℃, add hydroquinone, continue cooling to 115-125℃, add pentaerythritol triacrylate, under nitrogen protection throughout, control the stirring speed at 150-300 r / min, keep warm for 2.5-3.5 h, until the acid value of the system drops below 5 mg KOH / g, stop the reaction, keep at 115-125℃, and distill under reduced pressure at -0.095~-0.1 MPa for 25-35 min, cool to 55-65℃ and discharge to obtain 2,5-furandicarboxylic acid-itaconic acid block hyperbranched polyester acrylate resin; S2. Add dried 4-hydroxybenzophenone and ε-caprolactone to a reaction vessel, purge with nitrogen 2-4 times, start stirring, and control the stirring speed at 250-400 r / min. Heat to 130-135℃ and hold for 30 min until 4-hydroxybenzophenone is completely melted. Add stannous octoate and keep the reaction at 125-135℃ for 4.5-5.5 h until the hydroxyl value of the system drops to 55-65 mg KOH / g. Maintain at 125-135℃ and distill under reduced pressure at -0.095~-0.1 MPa for 25-35 min to obtain hydroxyl-terminated polycaprolactone-grafted 4-hydroxybenzophenone intermediate. The intermediate was cooled to 85-95℃, and acrylic acid, p-toluenesulfonic acid, and hydroquinone were added. Nitrogen was used to purge the mixture 2-4 times. Water generated during the reaction was continuously separated using a reflux condenser. The stirring speed was controlled at 200-350 r / min. The temperature was raised to 105-115℃ and held for 2.5-3.5 h until the acid value of the system dropped below 8 mg KOH / g. The reaction was then stopped. The temperature was maintained at 105-115℃, and the mixture was distilled under reduced pressure at a vacuum of -0.095~-0.1 MPa for 25-35 min. The mixture was then cooled to 45-55℃ and discharged to obtain 4-hydroxybenzophenone-grafted polycaprolactone monoacrylate photoinitiator. S3. Add the colorant, 10-15 parts of the resin obtained in step S1, and polyethylene wax dispersant to the reactor, purge with nitrogen 2-4 times, heat to 75-85℃, stir at 1000-1200 r / min for 30 min for pre-dispersion, and then stir at 800-1000 r / min for 1-2 h to obtain the pigment graft pre-dispersion. S4. Add the remaining resin obtained in step S1, 1,4-cyclohexanediethanol diacrylate, tetrahydrofuran acrylate, photoinitiator obtained in step S2, polyether-modified polydimethylsiloxane leveling agent, and antioxidant to the pigment graft predispersant obtained in step S3. Control the temperature to 35-40℃ and stir at 1400-1600 r / min for 10 min to premix. Keep the temperature and speed constant, and simultaneously irradiate intermittently with UV-LED light with a wavelength of 365nm and a power density of 0.3-0.5W / cm² to obtain the prepolymer mixture system. S5. Pass the prepolymerized mixture obtained in step S4 into a horizontal sand mill. The grinding media is 0.3-0.5mm zirconia beads. The grinding temperature is controlled below 35℃. Grind until the fineness of the system is ≤5μm to obtain the grinding material. S6. The abrasive material obtained in step S5 is fed into a high-pressure homogenizer, and the homogenization temperature is controlled to be ≤35℃. The homogenizer is circulated and homogenized twice under a pressure of 60-80MPa. Then it is transferred to a vacuum degassing kettle for degassing. The discharged material is a biodegradable, environmentally friendly, and aging-resistant UV ink.

[0013] Further, in step S1, by weight, 32-40 parts of 1,4-butanediol, 32-45 parts of itaconic acid, 30-32 parts of 2,5-furandicarboxylic acid, 0.2-0.3 parts of p-toluenesulfonic acid, 0.05-0.10 parts of initial hydroquinone, 0.10-0.15 parts of supplementary hydroquinone, and 18-22 parts of pentaerythritol triacrylate. The ratio of diacid to diol can control the esterification reaction process, enabling the prepolymer to form a stable terminal carboxyl structure and determining the number of reaction sites for subsequent end-capping reactions; the amount of p-toluenesulfonic acid can regulate the esterification reaction rate, avoiding excessively fast reactions that lead to an excessively wide molecular weight distribution; the stepwise addition of hydroquinone can inhibit the thermal self-polymerization of acrylate double bonds at each stage of the reaction, preventing the system from gelling; the amount of pentaerythritol triacrylate can control the hyperbranching degree and terminal acrylate functionality of the resin, enabling the resin to simultaneously possess UV curing activity and biodegradability.

[0014] Further, in step S2, by weight, 18-22 parts of 4-hydroxybenzophenone, 55-80 parts of ε-caprolactone, 0.08-0.20 parts of stannous octoate, 7-9 parts of acrylic acid, 0.15-0.25 parts of p-toluenesulfonic acid, and 0.08-0.12 parts of hydroquinone. The feeding ratio of 4-hydroxybenzophenone to ε-caprolactone can control the length of the polycaprolactone graft chain, enabling the photoinitiator to possess both degradability and photoinitiating activity; the amount of stannous octoate can regulate the reaction rate and molecular weight distribution of the ring-opening polymerization of ε-caprolactone, avoiding the generation of multifunctional impurities by side reactions; the amount of acrylic acid can ensure complete end-capillary sealing of the intermediate terminal hydroxyl groups, introducing acrylate double bonds that can participate in UV curing; the amounts of p-toluenesulfonic acid and hydroquinone can respectively regulate the esterification reaction rate, inhibit the thermal self-polymerization of acrylic acid double bonds, and ensure the structural stability of the target photoinitiator.

[0015] Furthermore, in step S4, the intermittent irradiation involves irradiating for 8-12 seconds followed by a pause of 18-22 seconds, with the actual cumulative irradiation time of the UV-LED lamp being 48-72 seconds. Setting pause intervals after short irradiation periods allows the system to dissipate heat during the irradiation intervals, preventing the shear heat generated by continuous irradiation from accumulating with the irradiation heat and causing excessive temperature rise. Simultaneously, it allows the generated free radicals to diffuse uniformly within the system, preventing excessively rapid local double bond polymerization and gel formation. The cumulative irradiation time allows for precise control of the double bond conversion rate within the system, ensuring that while the system forms an oligomer network, there is no abnormal increase in viscosity, guaranteeing the operability of subsequent grinding processes.

[0016] Furthermore, in step S6, degassing is performed under a vacuum of -0.095 to -0.1 MPa and a temperature of 30-35°C, with stirring at a speed of 250-350 r / min for 15-25 minutes. This vacuum range allows microbubbles in the system to expand and float rapidly before being removed, while preventing material loss due to excessively high vacuum causing the system to boil over. The temperature range of 30-35°C prevents premature decomposition of the photoinitiator and thermal self-polymerization of the resin double bonds caused by excessively high temperatures, while maintaining suitable fluidity of the system to aid in bubble removal. The stirring speed and degassing time ensure that the system is uniformly subjected to vacuum, guaranteeing complete bubble removal without introducing new bubbles due to excessively high speed, thus avoiding affecting the smoothness of the cured ink film.

[0017] The present invention discloses a method for preparing a biodegradable, environmentally friendly, and aging-resistant UV ink. The method involves preparing a UV-curable film-forming matrix and a copolymerizable macromolecular photoinitiator, performing in-situ grafting treatment on the pigment to improve the dispersion effect, controlling the prepolymerization degree of the system through low-temperature intermittent UV irradiation, and completing the ink preparation through ultrafine grinding, homogenization, and degassing treatment, thereby balancing the curing performance, stability in use, and biodegradability of the ink.

[0018] Compared with the prior art, the advantages of the present invention are: (1) The present invention achieves the synergy of biodegradability and aging resistance of UV ink, solving the problem that the two properties cannot be achieved simultaneously in the prior art; (2) This invention reduces the risk of photoinitiator migration in UV inks. The photoinitiator can be biodegraded synchronously with the ink matrix, leaving no residual pollution. (3) The present invention improves the dispersion uniformity of pigments in biodegradable polyester matrix, prolongs the storage stability period of ink, and avoids pigment agglomeration and sedimentation. (4) The present invention reduces the shrinkage rate of UV ink after curing, improves the adhesion of ink to the substrate, and optimizes printability; (5) The ink production process of this invention has no emissions of volatile organic compounds, and all components contain no prohibited environmentally friendly substances, thus meeting the requirements of clean production. Attached Figure Description

[0019] Figure 1 This is a comparison chart of the biodegradability rates of this invention; Figure 2 This is a comparison chart of the yellowing index ΔYI of the xenon lamp after 1000 hours of aging according to the present invention. Detailed Implementation

[0020] To facilitate understanding of the present invention, the present invention will be described more fully and in detail below with reference to the accompanying drawings and preferred embodiments, but the scope of protection of the present invention is not limited to the following specific embodiments.

[0021] Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the scope of the invention.

[0022] Unless otherwise specified, all raw materials, reagents, instruments and equipment used in this invention can be purchased from the market or prepared by existing methods. Example

[0023] A biodegradable, environmentally friendly, and aging-resistant UV ink of the present invention comprises, by weight, 65 parts of 2,5-furandicarboxylic acid-itaconic acid block hyperbranched polyester acrylate resin, 15 parts of 1,4-cyclohexanediethanol diacrylate, 15 parts of tetrahydrofuran acrylate, 8 parts of 4-hydroxybenzophenone-grafted polycaprolactone monoacrylate photoinitiator, 18 parts of rutile titanium dioxide, 1 part of polyether-modified polydimethylsiloxane leveling agent BYK-333, 1.5 parts of polyethylene wax dispersant BYK-9076, and 0.5 parts of antioxidant 1010.

[0024] The preparation method of the biodegradable, environmentally friendly, and aging-resistant UV ink in this embodiment includes the following steps: S1. Add 40 parts of 1,4-butanediol and 45 parts of itaconic acid to the reactor, start stirring, and control the stirring speed at 400 r / min. Add 32 parts of 2,5-furandicarboxylic acid, 0.3 parts of p-toluenesulfonic acid, and 0.10 parts of hydroquinone. Purge with nitrogen 4 times, and maintain nitrogen protection throughout the process. Heat to 150℃ and hold for pre-dispersion for 30 min. Heat to 170℃ and react for 3.5 h. Continuously separate the water generated in the reaction with a reflux condenser until the acid value of the system drops to 30 mg KOH / g. Maintain 170℃ and reduce compression polymerization under a vacuum of -0.1 MPa for 35 minutes. min, a carboxyl-terminated linear block polyester prepolymer was obtained; the prepolymer was cooled to 130℃, 0.15 parts of hydroquinone were added, and the temperature was further reduced to 125℃. 22 parts of pentaerythritol triacrylate were added. Nitrogen protection was maintained throughout the process, the stirring speed was controlled at 300 r / min, and the temperature was maintained for 3.5 h until the acid value of the system dropped below 5 mg KOH / g. The reaction was stopped, and the temperature was maintained at 125℃. The mixture was then distilled under reduced pressure at -0.1 MPa for 35 min, cooled to 65℃, and discharged to obtain 2,5-furandicarboxylic acid-itaconic acid block hyperbranched polyester acrylate resin. S2. Add 22 parts of dried 4-hydroxybenzophenone and 80 parts of ε-caprolactone to a reaction vessel. Purge with nitrogen four times, maintaining nitrogen protection throughout. Start stirring and control the stirring speed at 400 r / min. Heat to 135℃ and hold for 30 min until 4-hydroxybenzophenone is completely melted. Add 0.20 parts of stannous octoate and maintain the reaction at 135℃ for 5.5 h until the hydroxyl value of the system drops to 65 mg KOH / g. Maintain at 135℃ and distill under reduced pressure at -0.1 MPa for 35 min to obtain hydroxyl-terminated polycaprolactone grafted with 4-hydroxybenzophenone. Ketone intermediate; The intermediate was cooled to 95℃, and 9 parts of acrylic acid, 0.25 parts of p-toluenesulfonic acid, and 0.12 parts of hydroquinone were added. Nitrogen was purged 4 times, and the water generated during the reaction was continuously separated using a reflux condenser. The stirring speed was controlled at 350 r / min, and the temperature was raised to 115℃ and held for 3.5 h until the acid value of the system dropped below 8 mg KOH / g. The reaction was then stopped, and the temperature was maintained at 115℃. The mixture was then distilled under reduced pressure at -0.1 MPa for 35 min, cooled to 55℃, and discharged to obtain 4-hydroxybenzophenone-grafted polycaprolactone monoacrylate photoinitiator. S3. Add 18 parts of rutile titanium dioxide, 15 parts of the resin obtained in step S1, and 1.5 parts of BYK-9076 dispersant to the reactor. Replace with nitrogen 4 times and maintain nitrogen protection throughout the process. Heat to 85°C, stir at 1200 r / min for 30 min for pre-dispersion, and then stir at 1000 r / min for 2 h to obtain pigment graft pre-dispersion. S4. Add the remaining 50 parts of the resin obtained in step S1, 15 parts of 1,4-cyclohexanediethanol diacrylate, 15 parts of tetrahydrofuran acrylate, 8 parts of the photoinitiator obtained in step S2, 1 part of BYK-333 leveling agent, and 0.5 parts of antioxidant 1010 to the pigment graft predispersant obtained in step S3. Control the temperature to 40°C and stir at 1600 r / min for 10 min to premix. Keep the temperature and speed constant, and simultaneously irradiate intermittently with UV-LED light with a wavelength of 365 nm and a power density of 0.5 W / cm². After irradiating for 12 s, pause for 22 s. The total actual irradiation time of the UV-LED lamp is 72 s, and a prepolymer mixture system is obtained. S5. Pass the prepolymerized mixture obtained in step S4 into a horizontal sand mill, using 0.5mm zirconia beads as the grinding media, and control the grinding temperature below 35℃. Grind until the fineness of the system is ≤5μm to obtain the grinding material. S6. The abrasive material obtained in step S5 is fed into a high-pressure homogenizer, and the homogenization temperature is controlled to be ≤35℃. It is circulated and homogenized twice under a pressure of 80MPa. Then it is transferred to a vacuum degassing kettle and stirred and degassed at a speed of 350r / min for 25min under a vacuum of -0.1MPa and a temperature of 35℃. The material is discharged to obtain a biodegradable, environmentally friendly, and aging-resistant UV ink. Example

[0025] A biodegradable, environmentally friendly, and aging-resistant UV ink of the present invention comprises, by weight, 55 parts of 2,5-furandicarboxylic acid-itaconic acid block hyperbranched polyester acrylate resin, 11.5 parts of 1,4-cyclohexanediethanol diacrylate, 11 parts of tetrahydrofuran acrylate, 5.5 parts of 4-hydroxybenzophenone-grafted polycaprolactone monoacrylate photoinitiator, 11.5 parts of phthalocyanine blue BGS, 0.6 parts of polyether-modified polydimethylsiloxane leveling agent BYK-333, 0.9 parts of polyethylene wax dispersant BYK-9076, and 0.3 parts of antioxidant 1010.

[0026] The preparation method of the biodegradable, environmentally friendly, and aging-resistant UV ink in this embodiment includes the following steps: S1. Add 36 parts of 1,4-butanediol and 38.5 parts of itaconic acid to the reactor, start stirring, and control the stirring speed at 300 r / min. Add 31 parts of 2,5-furandicarboxylic acid, 0.25 parts of p-toluenesulfonic acid, and 0.075 parts of hydroquinone. Purge with nitrogen three times, and maintain nitrogen protection throughout the process. Raise the temperature to 147℃ and hold for pre-dispersion for 30 min. Raise the temperature to 165℃ and react for 3 h. Continuously separate the water generated in the reaction using a reflux condenser until the acid value of the system drops to 27.5 mg KOH / g. Maintain 165℃ and reduce the pressure under a vacuum of -0.0975 MPa. Polymerize for 30 min to obtain a carboxyl-terminated linear block polyester prepolymer; cool the prepolymer to 130℃, add 0.125 parts of hydroquinone, continue cooling to 120℃, add 20 parts of pentaerythritol triacrylate, under nitrogen protection throughout, control the stirring speed at 225 r / min, keep warm for 3 h, until the acid value of the system drops below 5 mg KOH / g, stop the reaction, keep at 120℃, and distill under reduced pressure at -0.0975 MPa for 30 min, cool to 60℃ and discharge to obtain 2,5-furandicarboxylic acid-itaconic acid block hyperbranched polyester acrylate resin; S2. Add 20 parts of dried 4-hydroxybenzophenone and 67.5 parts of ε-caprolactone to a reaction vessel, purge with nitrogen three times, and maintain nitrogen protection throughout the process. Start stirring and control the stirring speed at 325 r / min. Heat to 132℃ and hold for 30 min until 4-hydroxybenzophenone is completely melted. Add 0.14 parts of stannous octoate and maintain the reaction at 130℃ for 5 h until the hydroxyl value of the system drops to 60 mg KOH / g. Maintain the temperature at 130℃ and distill under reduced pressure at -0.0975 MPa for 30 min to obtain hydroxyl-terminated polycaprolactone grafted with 4-hydroxybenzophenone. Methyl ketone intermediate; the intermediate was cooled to 90℃, and 8 parts of acrylic acid, 0.20 parts of p-toluenesulfonic acid, and 0.10 parts of hydroquinone were added. The mixture was purged with nitrogen three times, and the water generated during the reaction was continuously separated using a reflux condenser. The stirring speed was controlled at 275 r / min, and the temperature was raised to 110℃ and held for 3 h until the acid value of the system dropped below 8 mg KOH / g. The reaction was then stopped, and the temperature was maintained at 110℃. The mixture was then distilled under reduced pressure at a vacuum of -0.0975 MPa for 30 min, and the product was cooled to 50℃ to obtain 4-hydroxybenzophenone-grafted polycaprolactone monoacrylate photoinitiator. S3. Add 11.5 parts of Phthalocyanine Blue BGS, 12.5 parts of the resin obtained in step S1, and 0.9 parts of BYK-9076 dispersant to the reactor. Purge with nitrogen three times and maintain nitrogen protection throughout the process. Heat to 80°C, stir at 1100 r / min for 30 min for pre-dispersion, and then stir at 900 r / min for 1.5 h to obtain the pigment graft pre-dispersion. S4. Add the remaining 42.5 parts of the resin obtained in step S1, 11.5 parts of 1,4-cyclohexanediethanol diacrylate, 11 parts of tetrahydrofuran acrylate, 5.5 parts of the photoinitiator obtained in step S2, 0.6 parts of BYK-333 leveling agent, and 0.3 parts of antioxidant 1010 to the pigment graft predispersant obtained in S3. Control the temperature to 37°C and stir at 1500 r / min for 10 min to premix. Keep the temperature and speed constant, and simultaneously irradiate intermittently with UV-LED light with a wavelength of 365 nm and a power density of 0.4 W / cm². After irradiating for 10 s, pause for 20 s. The total actual irradiation time of the UV-LED lamp is 60 s, and a prepolymer mixed system is obtained. S5. Pass the prepolymerized mixture obtained in step S4 into a horizontal sand mill, using 0.4mm zirconia beads as the grinding media, and control the grinding temperature below 35℃. Grind until the fineness of the system is ≤5μm to obtain the grinding material. S6. The abrasive material obtained in step S5 is fed into a high-pressure homogenizer, and the homogenization temperature is controlled to be ≤35℃. It is circulated and homogenized twice under a pressure of 70MPa. Then it is transferred to a vacuum degassing kettle and stirred and degassed at a speed of 300r / min for 20min under a vacuum of -0.0975MPa and a temperature of 32℃. The material is then discharged to obtain a biodegradable, environmentally friendly, and aging-resistant UV ink. Example

[0027] A biodegradable, environmentally friendly, and aging-resistant UV ink of the present invention comprises, by weight, 45 parts of 2,5-furandicarboxylic acid-itaconic acid block hyperbranched polyester acrylate resin, 8 parts of 1,4-cyclohexanediethanol diacrylate, 7 parts of tetrahydrofuran acrylate, 3 parts of 4-hydroxybenzophenone-grafted polycaprolactone monoacrylate photoinitiator, 5 parts of carbon black N330, 0.2 parts of polyether-modified polydimethylsiloxane leveling agent BYK-333, 0.3 parts of polyethylene wax dispersant BYK-9076, and 0.1 parts of antioxidant 1010.

[0028] The preparation method of the biodegradable, environmentally friendly, and aging-resistant UV ink in this embodiment includes the following steps: S1. Add 32 parts of 1,4-butanediol and 32 parts of itaconic acid to the reactor, start stirring, and control the stirring speed at 200 r / min. Add 30 parts of 2,5-furandicarboxylic acid, 0.2 parts of p-toluenesulfonic acid, and 0.05 parts of hydroquinone. Purge twice with nitrogen, and maintain nitrogen protection throughout the process. Raise the temperature to 145℃ and hold for pre-dispersion for 30 min. Raise the temperature to 160℃ and react for 2.5 h. Continuously separate the water generated in the reaction using a reflux condenser until the acid value of the system drops to 25 mg KOH / g. Maintain 160℃ and reduce the pressure to polymerize 25% under a vacuum of -0.095 MPa. min, a carboxyl-terminated linear block polyester prepolymer was obtained; the prepolymer was cooled to 130℃, 0.10 parts of hydroquinone were added, and the temperature was further reduced to 115℃. 18 parts of pentaerythritol triacrylate were added, and the entire process was carried out under nitrogen protection. The stirring speed was controlled at 150 r / min, and the temperature was maintained for 2.5 h until the acid value of the system dropped below 5 mg KOH / g. The reaction was stopped, and the temperature was maintained at 115℃. The mixture was then distilled under reduced pressure at -0.095 MPa for 25 min, and the product was discharged at 55℃ to obtain 2,5-furandicarboxylic acid-itaconic acid block hyperbranched polyester acrylate resin; S2. Add 18 parts of dried 4-hydroxybenzophenone and 55 parts of ε-caprolactone to a reaction vessel. Purge twice with nitrogen, maintaining nitrogen protection throughout. Start stirring and control the stirring speed at 250 r / min. Heat to 130℃ and hold for 30 min until 4-hydroxybenzophenone is completely melted. Add 0.08 parts of stannous octoate and maintain the reaction at 125℃ for 4.5 h until the hydroxyl value of the system drops to 55 mg KOH / g. Maintain at 125℃ and distill under reduced pressure at -0.095 MPa for 25 min to obtain hydroxyl-terminated polycaprolactone grafted with 4-hydroxybenzophenone. Ketone intermediate; The intermediate was cooled to 85℃, and 7 parts of acrylic acid, 0.15 parts of p-toluenesulfonic acid, and 0.08 parts of hydroquinone were added. Nitrogen was purged twice, and the water generated during the reaction was continuously separated using a reflux condenser. The stirring speed was controlled at 200 r / min, and the temperature was raised to 105℃ and held for 2.5 h until the acid value of the system dropped below 8 mg KOH / g. The reaction was then stopped, and the temperature was maintained at 105℃. The mixture was then distilled under reduced pressure at -0.095 MPa for 25 min, cooled to 45℃, and discharged to obtain 4-hydroxybenzophenone-grafted polycaprolactone monoacrylate photoinitiator. S3. Add 5 parts of carbon black N330, 10 parts of the resin obtained in step S1, and 0.3 parts of BYK-9076 dispersant to the reactor. Replace with nitrogen twice and maintain nitrogen protection throughout the process. Heat to 75°C, stir at 1000 r / min for 30 min for pre-dispersion, and then stir at 800 r / min for 1 h to obtain pigment graft pre-dispersion. S4. Add the remaining 35 parts of the resin obtained in step S1, 8 parts of 1,4-cyclohexanediethanol diacrylate, 7 parts of tetrahydrofuran acrylate, 3 parts of the photoinitiator obtained in step S2, 0.2 parts of BYK-333 leveling agent, and 0.1 parts of antioxidant 1010 to the pigment graft predispersant obtained in S3. Control the temperature to 35°C and stir at 1400 r / min for 10 min to premix. Keep the temperature and speed constant, and simultaneously irradiate intermittently with UV-LED light with a wavelength of 365 nm and a power density of 0.3 W / cm². Irradiate for 8 s and pause for 18 s. The total actual irradiation time of the UV-LED lamp is 48 s, and the prepolymer mixture system is obtained. S5. Pass the prepolymerized mixture obtained in step S4 into a horizontal sand mill, using 0.3mm zirconia beads as the grinding media, and control the grinding temperature below 35℃. Grind until the fineness of the system is ≤5μm to obtain the grinding material. S6. The abrasive material obtained in step S5 is fed into a high-pressure homogenizer, and the homogenization temperature is controlled to be ≤35℃. It is circulated and homogenized twice under a pressure of 60MPa. Then it is transferred to a vacuum degassing kettle and stirred and degassed at a speed of 250r / min for 15min under a vacuum of -0.095MPa and a temperature of 30℃. The material is discharged to obtain a biodegradable, environmentally friendly, and aging-resistant UV ink.

[0029] Comparative Example The preparation method of this comparative UV ink includes the following steps: S1. By weight, add 55 parts of polycaprolactone-type linear polyester acrylate, 12 parts of tripropylene glycol diacrylate, and 10 parts of 1,6-hexanediol diacrylate to a dispersion vessel, start stirring, control the stirring speed at 800 r / min, stir for 10 min until the system is mixed evenly, add 4 parts of photoinitiator benzophenone and 1 part of N,N-dimethylaniline, and continue stirring for 15 min until the photoinitiator is completely dissolved to obtain the resin base material; S2. Add 12 parts of rutile titanium dioxide, 0.6 parts of BYK-333 leveling agent, 0.9 parts of BYK-163 dispersant, and 0.3 parts of antioxidant 1010 to the resin base obtained in step S1. Increase the stirring speed to 1500 r / min and stir at room temperature for 30 min to obtain a pre-dispersed slurry. S3. Pass the pre-dispersed slurry obtained in step S2 into a horizontal sand mill, using 0.4mm zirconia beads as the grinding media, control the grinding temperature to ≤40℃, and grind until the fineness of the system is ≤5μm to obtain the grinding material; S4. Transfer the abrasive material obtained in step S3 into a vacuum degassing kettle, and stir and degas at 300 r / min for 20 min under a vacuum of -0.098 MPa and at room temperature to obtain UV ink.

[0030] The testing method is as follows: Biodegradation rate: According to the controlled aerobic composting test method specified in GB / T 19277.1-2011, the carbon dioxide release of the ink-cured film was tested in a constant temperature composting environment of 58±2℃ for 180 days, and the final biodegradation rate was calculated based on the theoretical carbon dioxide release. Yellowing index ΔYI after 1000h xenon lamp aging: According to the artificial climate aging method of filtered xenon arc lamp specified in GB / T 1865-2009, after 1000h continuous irradiation aging of the ink curing film, the yellowing index of the curing film before and after aging was tested according to GB / T 23983-2009, and the difference between the two was calculated to obtain ΔYI. Gloss retention rate after 1000h xenon lamp aging: According to the artificial climate aging method of filtered xenon arc lamp specified in GB / T 1865-2009, the ink curing film was subjected to 1000h continuous irradiation aging, and the 60° specular gloss of the curing film was tested according to GB / T 9754-2007. The gloss retention rate was calculated by the ratio of the gloss after aging to that before aging. Photoinitiator migration amount: According to the migration test method for food contact materials specified in GB 31604.1-2015 and EU 10 / 2011, 75% ethanol aqueous solution was used as food simulant. The ink curing film was immersed in the solution at a constant temperature of 40℃ for 72h. The migration amount of photoinitiator in the immersion solution was quantitatively tested using high performance liquid chromatography-ultraviolet detector. Viscosity change rate after 6 months of storage: According to the ink viscosity test method specified in GB / T 13217.3-2009, the initial viscosity of the ink was tested using a rotational viscometer at a constant temperature of 25℃. The ink was then sealed in a light-proof environment and stored at room temperature of 25℃ for 6 months. The viscosity after storage was tested under the same conditions, and the viscosity change rate was calculated. Pigment sedimentation after 6 months of storage: The ink was placed in a sealed glass graduated cylinder with precise scale, sealed in the dark, and left to stand vertically at room temperature (25°C) for 6 months. The stratification of the system was recorded. UV curing shrinkage rate: The density bottle method specified in GB / T 6750-2023 was used to test the liquid density of the ink before curing at a constant temperature of 25℃ and the solid density after curing with 365nm UV-LED light. The volume curing shrinkage rate of the UV ink was calculated by the density change before and after curing. Film substrate adhesion: The ink is uniformly coated on the corona-treated BOPP film substrate, and after being completely cured into a film by 365nm UV-LED light at 800mJ / cm², the substrate adhesion of the cured film is tested using a 1mm spacing cross-cut tester according to the cross-cut test method specified in GB / T 9286-1998.

[0031] Table 1: Experimental Results of Examples 1-3 and Comparative Examples

[0032] In summary, refer to Table 1 and Figure 1-2 Examples 1-3 of this invention achieve a synergistic effect of high biodegradability and aging resistance through a block hyperbranched resin synthesis process. The compost degradation rate of each example exceeds 92% after 180 days, and the yellowing index after 1000 hours of xenon lamp aging is significantly lower than that of the comparative example. Through a copolymerizable macromolecular photoinitiator synthesis process, the photoinitiator migration is controlled to within 0.01 mg / kg, far superior to the small molecule photoinitiator system of the comparative example. Through pigment grafting pretreatment and gradient prepolymerization processes, the ink storage stability is significantly improved, the curing shrinkage rate is reduced, and the substrate adhesion is guaranteed. All performance characteristics are significantly better than those of the comparative example prepared by conventional processes.

Claims

1. A biodegradable, environmentally friendly, and aging-resistant UV ink, characterized in that: By weight, it includes the following components: 45-65 parts of 2,5-furandicarboxylic acid-itaconic acid block hyperbranched polyester acrylate resin; 8-15 parts of 1,4-cyclohexanediethanol diacrylate; 7-15 parts of tetrahydrofuran acrylate; 3-8 parts of 4-hydroxybenzophenone-grafted polycaprolactone monoacrylate photoinitiator; 5-18 parts of colorant; 0.2-1 parts of polyether-modified polydimethylsiloxane leveling agent; 0.3-1.5 parts of polyethylene wax dispersant; Antioxidant 0.1-0.5 parts.

2. The biodegradable, environmentally friendly, and aging-resistant UV ink according to claim 1, characterized in that: The colorant is any one of rutile titanium dioxide, phthalocyanine blue BGS, or carbon black N330.

3. The biodegradable, environmentally friendly, and aging-resistant UV ink according to claim 1, characterized in that: The polyether-modified polydimethylsiloxane leveling agent is BYK-333.

4. The biodegradable, environmentally friendly, and aging-resistant UV ink according to claim 1, characterized in that: The polyethylene wax dispersant is BYK-9076.

5. The biodegradable, environmentally friendly, and aging-resistant UV ink according to claim 1, characterized in that: The antioxidant is antioxidant 1010.

6. A method for preparing a biodegradable, environmentally friendly, and aging-resistant UV ink, characterized in that: Includes the following steps, S1. Add 1,4-butanediol and itaconic acid to the reactor, start stirring, and control the stirring speed at 200-400 r / min. Add 2,5-furandicarboxylic acid, p-toluenesulfonic acid, and hydroquinone. Purge with nitrogen 2-4 times, and maintain nitrogen protection throughout the process. Raise the temperature to 145-150℃ and hold for pre-dispersion for 30 min. Raise the temperature to 160-170℃ and react for 2.5-3.5 h. Continuously separate the water generated in the reaction using a reflux condenser until the acid value of the system drops to 25-30 mg KOH / g. Maintain the temperature at 160-170℃ and reduce the pressure for 25-35 min under a vacuum of -0.095~-0.1 MPa. n, to obtain a carboxyl-terminated linear block polyester prepolymer; cool the prepolymer to 130℃, add hydroquinone, continue cooling to 115-125℃, add pentaerythritol triacrylate, under nitrogen protection throughout, control the stirring speed at 150-300 r / min, keep warm for 2.5-3.5 h, until the acid value of the system drops below 5 mg KOH / g, stop the reaction, keep at 115-125℃, and distill under reduced pressure at -0.095~-0.1 MPa for 25-35 min, cool to 55-65℃ and discharge to obtain 2,5-furandicarboxylic acid-itaconic acid block hyperbranched polyester acrylate resin; S2. Add dried 4-hydroxybenzophenone and ε-caprolactone to a reaction vessel, purge with nitrogen 2-4 times, and maintain nitrogen protection throughout the process. Start stirring and control the stirring speed at 250-400 r / min. Heat to 130-135℃ and hold for 30 min until 4-hydroxybenzophenone is completely melted. Add stannous octoate and maintain the reaction at 125-135℃ for 4.5-5.5 h until the hydroxyl value of the system drops to 55-65 mg KOH / g. Maintain the temperature at 125-135℃ and distill under reduced pressure at a vacuum of -0.095~-0.1 MPa for 25-35 min to obtain hydroxyl-terminated polycaprolactone grafted with 4-hydroxybenzophenone. Methyl ketone intermediate; cool the intermediate to 85-95℃, add acrylic acid, p-toluenesulfonic acid, and hydroquinone, purge with nitrogen 2-4 times, continuously separate the water generated during the reaction with a reflux condenser, control the stirring speed at 200-350 r / min, heat to 105-115℃ and hold for 2.5-3.5 h until the acid value of the system drops below 8 mg KOH / g, stop the reaction, maintain 105-115℃, and distill under reduced pressure at -0.095~-0.1 MPa for 25-35 min, cool to 45-55℃ and discharge to obtain 4-hydroxybenzophenone grafted polycaprolactone monoacrylate photoinitiator; S3. Add the colorant, 10-15 parts of the resin obtained in step S1, and polyethylene wax dispersant to the reactor. Replace with nitrogen 2-4 times, and maintain nitrogen protection throughout the process. Heat to 75-85℃, stir at 1000-1200 r / min for 30 min for pre-dispersion, and then stir at 800-1000 r / min for 1-2 h to obtain the pigment graft pre-dispersion. S4. Add the remaining resin obtained in step S1, 1,4-cyclohexanediethanol diacrylate, tetrahydrofuran acrylate, photoinitiator obtained in step S2, polyether-modified polydimethylsiloxane leveling agent, and antioxidant to the pigment graft predispersant obtained in step S3. Control the temperature to 35-40℃ and stir at 1400-1600 r / min for 10 min to premix. Keep the temperature and speed constant, and simultaneously irradiate intermittently with UV-LED light with a wavelength of 365nm and a power density of 0.3-0.5W / cm² to obtain the prepolymer mixture system. S5. Pass the prepolymerized mixture obtained in step S4 into a horizontal sand mill. The grinding media is 0.3-0.5mm zirconia beads. The grinding temperature is controlled below 35℃. Grind until the fineness of the system is ≤5μm to obtain the grinding material. S6. The abrasive material obtained in step S5 is fed into a high-pressure homogenizer, and the homogenization temperature is controlled to be ≤35℃. The homogenizer is circulated and homogenized twice under a pressure of 60-80MPa. Then it is transferred to a vacuum degassing kettle for degassing. The discharged material is a biodegradable, environmentally friendly, and aging-resistant UV ink.

7. The method for preparing the biodegradable, environmentally friendly, and aging-resistant UV ink according to claim 6, characterized in that: In step S1, by weight, there are 32-40 parts of 1,4-butanediol, 32-45 parts of itaconic acid, 30-32 parts of 2,5-furandicarboxylic acid, 0.2-0.3 parts of p-toluenesulfonic acid, 0.05-0.10 parts of initial hydroquinone, 0.10-0.15 parts of supplementary hydroquinone, and 18-22 parts of pentaerythritol triacrylate.

8. The method for preparing the biodegradable, environmentally friendly, and aging-resistant UV ink according to claim 6, characterized in that: In step S2, by weight, there are 18-22 parts of 4-hydroxybenzophenone, 55-80 parts of ε-caprolactone, 0.08-0.20 parts of stannous octoate, 7-9 parts of acrylic acid, 0.15-0.25 parts of p-toluenesulfonic acid, and 0.08-0.12 parts of hydroquinone.

9. The method for preparing the biodegradable, environmentally friendly, and aging-resistant UV ink according to claim 6, characterized in that: In step S4, the intermittent irradiation is performed by pausing for 18-22 seconds after each irradiation, and the cumulative duration of the UV-LED lamp being lit is 48-72 seconds.

10. The method for preparing the biodegradable, environmentally friendly, and aging-resistant UV ink according to claim 6, characterized in that: In step S6, degassing is performed under vacuum conditions of -0.095 to -0.1 MPa and 30-35°C, with stirring at a speed of 250-350 r / min for 15-25 min.

Images