Nanometer zinc oxide enhanced UV-cured luminescent ink and preparation method thereof

Abstract

The application discloses a kind of nano zinc oxide enhanced UV curing luminous ink and preparation method thereof, belong to ink technical field, the nano zinc oxide enhanced UV curing luminous ink, including the following raw materials: nano zinc oxide 15-21 parts;2-hydroxybenzophenone 3.6-7.8 parts;Isosorbide dimethyl ether 78-95 parts;Epoxy acrylate resin 18-27 parts;Polyester acrylate resin 32-38 parts;Acrylate 47-65 parts;Luminous powder 17-23 parts;Defoaming agent 0.6-1.2 parts;Dispersing agent 0.8-2.1 parts;Leveling agent 1.4-1.8 parts;Photoinitiator 0.6-0.9 parts.The application is short in total preparation time, and production efficiency is greatly improved;In addition, the application speeds up the curing speed, and the water resistance is also significantly improved;The dispersion rate of luminous powder is improved by the way of nano zinc oxide coated with luminous powder, so that the prepared nano zinc oxide enhanced UV curing luminous ink presents more uniform fluorescent effect.

Description

Technical Field

[0001] The present invention relates to the technical field of inks, and in particular to a nano zinc oxide enhanced UV (ultraviolet light) curing luminous ink and a preparation method thereof. Background Art

[0002] UV inks have garnered widespread attention in recent years and become a key material in the printing industry due to their solvent-free, fast drying, excellent gloss, and water and abrasion resistance. While thermosetting luminescent inks have traditionally been used in the production of luminous signs, technological advancements have led to the emergence of UV luminescent inks, particularly due to their faster curing speed, enhanced environmental friendliness, and superior physical properties, making them an ideal alternative to thermosetting luminescent inks. By incorporating luminescent powders into inks, luminescent inks can be produced, finding widespread application in areas such as luminous signs, specialty printed materials, and safety markings.

[0003] For example, Chinese patent CN117327422B discloses a synthesis process for UV-curable polyurethane inks, in which hydrophilic and antibacterial imidazole salt functional groups and alkenyl functional groups are grafted onto the side chains of polyurethane. The resulting imidazole salt-based polyurethane exhibits excellent UV light-curing properties. This material not only has a fast curing rate, but also uses water as a solvent, reflecting the advantages of green environmental protection. At the same time, through the chain extension reaction, the polyurethane paint film obtained has excellent water resistance, low water absorption, high hardness and strong adhesion. In addition, imidazole salt-based polyurethane also has good antibacterial properties, giving it broad application prospects in fields such as water-based inks. This innovative synthesis process provides new ideas for the research and development of UV-curable inks, especially in application scenarios with high requirements for environmental protection and functionality, showing significant advantages.

[0004] However, despite the numerous advantages of this process, its preparation also has some limitations. For example, the reaction process is complex, requiring at least 15 hours to complete, which is time-consuming and leaves room for improvement in production efficiency. Furthermore, while the UV-curable polyurethane ink produced in this patent already exhibits good water resistance, in certain specialized applications, particularly in high-humidity environments, the ink's water resistance still needs to be further optimized. Summary of the Invention

[0005] In view of the above-mentioned shortcomings of the prior art, the present invention provides a nano zinc oxide enhanced UV curable luminous ink and a preparation method thereof.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0007] A nano-zinc oxide-enhanced UV-curable luminous ink comprises the following raw materials in parts by weight: 15-21 parts of nano-zinc oxide; 3.6-7.8 parts of 2-hydroxybenzophenone; 78-95 parts of isosorbide dimethyl ether; 18-27 parts of epoxy acrylic resin; 32-38 parts of polyester acrylic resin; 47-65 parts of acrylate; 17-23 parts of luminous powder; 0.6-1.2 parts of defoaming agent; 0.8-2.1 parts of dispersant; 1.4-1.8 parts of leveling agent; and 0.6-0.9 parts of photoinitiator.

[0008] A method for preparing the nano zinc oxide enhanced UV curable luminous ink comprises the following steps:

[0009] Step 1: Take luminous powder and nano zinc oxide, add them to isosorbide dimethyl ether, stir and react at room temperature, filter, wash and dry to obtain nano zinc oxide coated with luminous powder;

[0010] Step 2: adding epoxy acrylic resin, polyester acrylic resin and acrylate mixed with a dispersant to the nano zinc oxide coated with luminous powder, and stirring to obtain a dispersion;

[0011] Step 3: Ultrasonic dispersion of the dispersion liquid, leveling agent, defoaming agent, and 2-hydroxybenzophenone in step 2 was added, and the temperature was raised to 50-55°C, then lowered to 3-5°C and then raised to room temperature, and a photoinitiator was added, and ultrasonic dispersion was continued;

[0012] Step 4: Filter to obtain nano zinc oxide enhanced UV curable luminous ink.

[0013] Furthermore, step one is specifically as follows: 17-23 parts of luminous powder and 15-21 parts of nano zinc oxide are added to 78-95 parts of isosorbide dimethyl ether, stirred at room temperature for 40-60 minutes, filtered, washed and dried to obtain nano zinc oxide coated with luminous powder.

[0014] Furthermore, step 2 is specifically as follows: adding 18-27 parts of epoxy acrylic resin, 32-38 parts of polyester acrylic resin and 47-65 parts of acrylate mixed with 0.8-2.1 parts of dispersant to the nano zinc oxide coated with luminous powder, and stirring for 10-25 minutes to obtain a dispersion.

[0015] Furthermore, step three is specifically as follows: ultrasonically disperse the dispersion of step two, 1.4-1.8 parts of leveling agent, 0.6-1.2 parts of defoaming agent, and 3.6-7.8 parts of 2-hydroxybenzophenone for 2-3 hours, heat to 50-55 ° C and keep warm for 20-30 minutes, cool to 3-5 ° C and keep warm for 20-30 minutes, heat to room temperature, add 0.6-0.9 parts of photoinitiator, and continue ultrasonic dispersion for 1-1.5 hours.

[0016] Furthermore, the pore diameter during filtration in step four is 80-100 μm.

[0017] Furthermore, the leveling agent is selected from one or more of BYK333, TEGO450 or LGH7499 leveling agents.

[0018] Furthermore, the dispersant is TEGODispers 685 or TEGODispers 688.

[0019] Furthermore, the particle size of the luminous powder is 50-60 μm.

[0020] Furthermore, the particle size of the nano zinc oxide is 40-50 nm.

[0021] Compared with the existing technology, the present invention has the following beneficial effects: the total preparation time of the present invention is short (the whole process is about 6 hours), which greatly improves the production efficiency; in addition, the present invention accelerates the curing speed and significantly improves the water resistance; the dispersion rate of the luminous powder is increased by coating the nano-zinc oxide with the luminous powder, so that the fluorescent effect of the prepared nano-zinc oxide-enhanced UV-curable luminous ink is more uniform. DETAILED DESCRIPTION

[0022] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, 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 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 making creative efforts are within the scope of protection of the present invention.

[0023] Example 1: This example provides a method for preparing a nano zinc oxide enhanced UV curable luminous ink, comprising the following steps:

[0024] Step 1: Take 23 parts of luminous powder and 21 parts of nano zinc oxide, add them to 95 parts of isosorbide dimethyl ether, stir at room temperature at a speed of 500 rpm for 60 minutes, filter, wash and dry to obtain nano zinc oxide coated with luminous powder;

[0025] Step 2: Add 27 parts of epoxy acrylic resin, 38 parts of polyester acrylic resin and 65 parts of acrylate mixed with 2.1 parts of dispersant to the nano zinc oxide coated with luminous powder, and stir for 25 minutes to obtain a dispersion;

[0026] Step 3: ultrasonically disperse the dispersion of step 2, 1.8 parts of leveling agent, 1.2 parts of defoaming agent, and 7.8 parts of 2-hydroxybenzophenone for 3 hours, then heat to 50°C and keep warm for 30 minutes, then cool to 5°C and keep warm for 30 minutes, then heat to room temperature, add 0.9 parts of photoinitiator, and continue ultrasonic dispersion for 1.5 hours;

[0027] The leveling agent is BYK333;

[0028] The defoamer is GPES type defoamer;

[0029] The dispersant is TEGODispers 685;

[0030] The particle size of the glow-in-the-dark powder is 60 μm;

[0031] The particle size of the nano zinc oxide is 50 nm;

[0032] The luminous powder is selected from existing commercial products, such as the rare earth luminous powder (long afterglow luminous powder) disclosed in Chinese patent CN103254663B;

[0033] Step 4: Filter through a 100 μm filter membrane to obtain nano zinc oxide enhanced UV curable luminous ink.

[0034] The nano zinc oxide enhanced UV curing luminous ink prepared by the present invention has a hardness of 5H, which meets the industry standard.

[0035] Example 2: This example provides a method for preparing a nano zinc oxide enhanced UV curable luminous ink, comprising the following steps:

[0036] Step 1: Take 17 parts of luminous powder and 15 parts of nano zinc oxide, add them to 78 parts of isosorbide dimethyl ether, stir at room temperature at a speed of 500 rpm for 40 minutes, filter, wash and dry to obtain nano zinc oxide coated with luminous powder;

[0037] Step 2: Add 18 parts of epoxy acrylic resin, 32 parts of polyester acrylic resin and 47 parts of acrylate mixed with 0.8 parts of dispersant to the nano zinc oxide coated with luminous powder, and stir for 10 minutes to obtain a dispersion;

[0038] Step 3: ultrasonically disperse the dispersion of step 2, 1.4 parts of leveling agent, 0.6 parts of defoaming agent, and 3.6 parts of 2-hydroxybenzophenone for 2 hours, then heat to 55°C and keep warm for 20 minutes, then cool to 3°C and keep warm for 20 minutes, then heat to room temperature, add 0.6 parts of photoinitiator, and continue ultrasonic dispersion for 1 hour;

[0039] The leveling agent is LGH7499 leveling agent;

[0040] The defoamer is GPES type defoamer;

[0041] The dispersant is TEGODispers 688;

[0042] The particle size of the luminous powder is 50 μm;

[0043] The particle size of the nano zinc oxide is 40 nm;

[0044] Step 4: Pass through an 80 μm filter membrane to obtain nano zinc oxide enhanced UV curable luminous ink.

[0045] Example 3: This example provides a method for preparing a nano zinc oxide enhanced UV curable luminous ink, comprising the following steps:

[0046] Step 1: Take 20 parts of luminous powder and 18 parts of nano zinc oxide, add them to 85 parts of isosorbide dimethyl ether, stir at 500 rpm, react for 52 minutes at room temperature, filter, wash and dry to obtain nano zinc oxide coated with luminous powder;

[0047] Step 2: Add 21 parts of epoxy acrylic resin, 35 parts of polyester acrylic resin and 58 parts of acrylate mixed with 1.4 parts of dispersant to the nano zinc oxide coated with luminous powder, and stir for 21 minutes to obtain a dispersion;

[0048] Step 3: ultrasonically disperse the dispersion obtained in step 2, 1.5 parts of leveling agent, 1.1 parts of defoaming agent, and 5.6 parts of 2-hydroxybenzophenone for 2.5 hours, then heat to 52°C and keep warm for 25 minutes, then cool to 4°C and keep warm for 22 minutes, then heat to room temperature, add 0.8 parts of photoinitiator, and continue ultrasonic dispersion for 1 hour;

[0049] The leveling agent is TEGO450 leveling agent;

[0050] The defoamer is GPES type defoamer;

[0051] The dispersant is TEGODispers 685;

[0052] The particle size of the glow-in-the-dark powder is 54 μm;

[0053] The particle size of the nano zinc oxide is 42 nm;

[0054] Step 4: Pass through a 90 μm filter membrane to obtain nano zinc oxide enhanced UV curable luminous ink.

[0055] Comparative Example 1:

[0056] The difference between this comparative example and Example 3 is that in step 3, the temperature is not lowered to 4°C and then raised, but directly lowered to room temperature;

[0057] The embodiment provides a preparation method of a nano zinc oxide reinforced UV-cured luminescent ink, and comprises the following steps:

[0058] Step one: 20 parts of luminescent powder and 18 parts of nano zinc oxide are added into 85 parts of isosorbide dimethyl ether, stirring reaction is carried out at a rotating speed of 500 r / min and room temperature for 52 min, and after filtration, washing and drying, the nano zinc oxide coated with the luminescent powder is obtained;

[0059] Step two: 21 parts of epoxy acrylate resin, 35 parts of polyester acrylate resin and 58 parts of acrylate mixed with 1.4 parts of dispersant are added into the nano zinc oxide coated with the luminescent powder, and a dispersion liquid is obtained after stirring for 21 min;

[0060] Step three: the dispersion liquid in step two, 1.5 parts of leveling agent, 1.1 parts of defoaming agent and 5.6 parts of 2-hydroxybenzophenone are stirred for 2.5 h, then the temperature is increased to 52 DEG C and kept for 25 min, then the temperature is decreased to room temperature, 0.8 parts of photoinitiator is added, and stirring is continued for 1 h;

[0061] The leveling agent is TEGO 450 leveling agent;

[0062] The defoaming agent is GPES type defoaming agent;

[0063] The dispersant is TEGO Dispers 685;

[0064] The particle size of the luminescent powder is 54 mu m;

[0065] The particle size of the nano zinc oxide is 42 nm;

[0066] Step four: a nano zinc oxide reinforced UV-cured luminescent ink is prepared by passing through a 90 mu m filter membrane.

[0067] Comparative example 2:

[0068] The difference between the comparative example and example 3 is that 2-hydroxybenzophenone is not added;

[0069] The embodiment provides a preparation method of a nano zinc oxide reinforced UV-cured luminescent ink, and comprises the following steps:

[0070] Step one: 20 parts of luminescent powder and 18 parts of nano zinc oxide are added into 85 parts of isosorbide dimethyl ether, stirring reaction is carried out at a rotating speed of 500 r / min and room temperature for 52 min, and after filtration, washing and drying, the nano zinc oxide coated with the luminescent powder is obtained;

[0071] Step two: 21 parts of epoxy acrylate resin, 35 parts of polyester acrylate resin and 58 parts of acrylate mixed with 1.4 parts of dispersant are added into the nano zinc oxide coated with the luminescent powder, and a dispersion liquid is obtained after stirring for 21 min;

[0072] Step 3: After ultrasonically dispersing the dispersion obtained in step 2, 1.5 parts of leveling agent, and 1.1 parts of defoaming agent for 2.5 hours, the temperature was raised to 52°C and kept for 25 minutes, then lowered to 4°C and kept for 22 minutes, and then raised to room temperature. 0.8 parts of photoinitiator were added and ultrasonic dispersion was continued for 1 hour.

[0073] The leveling agent is TEGO450 leveling agent;

[0074] The defoamer is GPES type defoamer;

[0075] The dispersant is TEGODispers 685;

[0076] The particle size of the glow-in-the-dark powder is 54 μm;

[0077] The particle size of the nano zinc oxide is 42 nm;

[0078] Step 4: Pass through a 90 μm filter membrane to obtain UV curable luminous ink.

[0079] Comparative Example 3:

[0080] The difference between this comparative example and Example 3 is that in step 3, the temperature was not lowered to 4°C and then raised, but directly lowered to room temperature and 2-hydroxybenzophenone was not added;

[0081] This embodiment provides a method for preparing a nano zinc oxide enhanced UV curable luminous ink, comprising the following steps:

[0082] Step 1: Take 20 parts of luminous powder and 18 parts of nano zinc oxide, add them to 85 parts of isosorbide dimethyl ether, stir at 500 rpm, react for 52 minutes at room temperature, filter, wash and dry to obtain nano zinc oxide coated with luminous powder;

[0083] Step 2: Add 21 parts of epoxy acrylic resin, 35 parts of polyester acrylic resin and 58 parts of acrylate mixed with 1.4 parts of dispersant to the nano zinc oxide coated with luminous powder, and stir for 21 minutes to obtain a dispersion;

[0084] Step 3: Stir the dispersion from step 2, 1.5 parts of leveling agent, and 1.1 parts of defoamer for 2.5 hours, then heat to 52°C and keep warm for 25 minutes, then cool to room temperature, add 0.8 parts of photoinitiator, and continue stirring for 1 hour;

[0085] The leveling agent is TEGO450 leveling agent;

[0086] The defoamer is GPES type defoamer;

[0087] The dispersant is TEGODispers 685;

[0088] The particle size of the glow-in-the-dark powder is 54 μm;

[0089] The particle size of the nano zinc oxide is 42 nm;

[0090] Step 4: Pass through a 90 μm filter membrane to obtain nano zinc oxide enhanced UV curable luminous ink.

[0091] Experimental Example: The performance of the nano zinc oxide enhanced UV curable luminous ink prepared in Examples 1-3 and Comparative Examples 1-3 was tested, and the results were as follows:

[0092] Curing the UV-curable luminous ink in a UV curing machine by spraying and recording the curing time;

[0093] Sample preparation: 75mm×150mm sample;

[0094] Number of samples: Prepare 3 samples for each group, and take the average value of the data; select a suitable substrate (glass slide), the substrate surface should be smooth, clean, free of oil or other contaminants, the substrate size should not be smaller than the sample size, and use isopropyl alcohol cleaner to thoroughly clean the substrate surface to ensure that there is no residue before spraying.

[0095] Curing conditions: The linear power of the curing light source is 200W / cm, and the ink thickness is 15 microns;

[0096] Water tank: A corrosion-resistant water tank should be used, and the water in the tank should be able to completely cover the specimen;

[0097] Constant temperature water bath device: equipped with a constant temperature control system to maintain the water temperature in the water tank within the temperature range required by the test (such as 38±1℃).

[0098] Bracket: used to fix the specimen vertically or horizontally in the water tank so that it is completely immersed in water;

[0099] Temperature control: The water temperature in the water tank is controlled at 38±1℃ and ensure that the temperature remains constant throughout the test;

[0100] Soaking time: According to ASTM D870-2002, the soaking time is 24 hours;

[0101] Water quality requirements: Use deionized water to avoid impurities or chemicals in the water that may affect the test results;

[0102] Test steps:

[0103] Specimen fixation: Fix the cured UV light-curing resin film specimen vertically or horizontally on the bracket, ensuring that the specimen is completely immersed in water and does not touch the bottom of the water tank.

[0104] Water immersion: Place the holder containing the sample in a constant temperature water bath, start timing, ensure that the water temperature is stable at 38±1℃, and the water completely covers the sample;

[0105] Regular inspection: After the prescribed immersion time is over, take out the sample and immediately conduct appearance and performance inspection;

[0106] Result evaluation:

[0107] Appearance observation: Observe the surface of the sample for bubbles, peeling, cracking, expansion or discoloration;

[0108] Performance test: Perform performance test on the sample after immersion;

[0109] Prepare the sample according to GB / T 13217.1, scrape the sample and let it sit for 24 hours; stick the tape on the ink-printed surface (the tape coverage does not include the edge of the ink-printed sample), roll it back and forth on the adhesive tape roller three times, let it sit for 5 minutes, clamp the sample on disk A, fix the exposed tape on disk B, and then turn on the machine. Rotate disk A at a speed of 0.6 to 1.0 m / s to peel off the tape.

[0110] A(%)=A1 / (A1+A2)*100%

[0111] A: Ink adhesion fastness

[0112] A1: Number of grids in the ink layer

[0113] A2: Number of cells of the ink layer removed

[0114] Change in adhesion fastness: A (before immersion) - A (after immersion)

[0115]

[0116] The change in adhesion fastness before and after immersion is significantly improved, indicating that the water resistance of Comparative Example 1-2 is reduced;

[0117] The total preparation time of the present invention is short (the whole process is about 6 hours), which greatly improves the production efficiency. In addition, through the comparison of Examples 1-3 and Comparative Examples 1-3, it can be seen that the present invention accelerates the curing speed by adding 2-hydroxybenzophenone and step three, and the water resistance is also significantly improved. The dispersion rate of the luminous powder is increased by coating the nano-zinc oxide with the luminous powder, so that the fluorescent effect of the prepared nano-zinc oxide-enhanced UV-curable luminous ink is more uniform.

[0118] 2-Hydroxybenzophenone is a widely used UV absorber. When added to UV-curable resins, 2-Hydroxybenzophenone may have the following major effects: Enhanced UV resistance: UV shielding: 2-Hydroxybenzophenone absorbs UV-A and UV-B wavelengths in the UV spectrum, acting as a UV shield. This helps protect the UV-curable resin from degradation under long-term exposure to sunlight or other UV sources, thereby extending the material's service life. Improved photostability: By absorbing UV rays, 2-Hydroxybenzophenone reduces UV damage to the resin's molecular chains, preventing photodegradation or yellowing, and improving the material's photostability. Impacts on the UV-curing process: Potential reduction in curing rate: Due to its UV-absorbing properties, 2-Hydroxybenzophenone may absorb some of the UV light used to initiate the UV-curing reaction, reducing the amount of light reaching the photoinitiator and potentially slowing the UV-curing reaction. Its UV absorption may also have a positive impact on weatherability. Changes in optical properties: The addition of 2-Hydroxybenzophenone may slightly affect the resin's transparency or color. In the present invention, Comparative Examples 1-3 also confirm that the addition of 2-hydroxybenzophenone alone does have a negative effect on the photocuring speed.

[0119] However, in the present invention, the addition of 2-hydroxybenzophenone primarily accelerates the curing speed and improves water resistance. This may be due to: the sensitizing effect of 2-hydroxybenzophenone; the synergistic effect of energy transfer and photoinitiator: In the present invention, 2-HBP is added to the photocurable resin system and subjected to ultrasonic dispersion and temperature regulation. As a UV absorber, 2-HBP may transfer the absorbed energy to the photoinitiator through energy transfer after absorbing UV light. Because the absorption spectrum of the photoinitiator may overlap with that of 2-HBP, the energy transfer effect may excite the photoinitiator more quickly, generating more free radicals and accelerating the curing speed. Potential photoinitiator activity: Although 2-HBP is typically used as a UV absorber, under certain conditions, 2-HBP may generate some active intermediates after absorbing UV light. These intermediates may have the ability to initiate free radical reactions. Ultrasonic dispersion and temperature regulation may enhance the photoinitiator effect of 2-HBP, further accelerating the photocuring speed. Uniform dispersion improves photoinitiator efficiency: In this invention scheme, the ultrasonic dispersion process significantly increases the uniformity of the system, especially the interaction between 2-HBP and the photoinitiator is more complete. This may enable the photoinitiator to absorb ultraviolet light more evenly throughout the system, reduce the phenomenon of local photoinitiator oversaturation or deficiency, and thus accelerate the overall curing speed. Thermosensitive effect enhances the reaction rate: The temperature change mentioned in the step (raising the temperature to 50°C, then lowering it to 4°C, and finally raising it to room temperature) may affect the photochemical reaction kinetics of 2-HBP. The temperature change may optimize the binding state or energy transfer efficiency of 2-HBP and the photoinitiator, especially at 50°C, 2-HBP may be in an efficient energy transfer or activation state, thereby accelerating the curing reaction. Spectral regulation effect: The introduction of 2-HBP may change the overall optical properties of the resin system, such as changing the refraction or reflection characteristics of light, so that more ultraviolet light can effectively act on the photoinitiator. This change may lead to an increase in the excitation efficiency of the photoinitiator, thereby accelerating the curing speed.

[0120] Furthermore, in terms of water resistance, neither the special temperature variation procedure alone nor the addition of 2-hydroxybenzophenone had a significant impact. However, when both were present in the protocol, the water resistance of the resin was significantly improved. The reason could be as follows: the effect of temperature on 2-HBP: The molecular structure and polar groups (such as hydroxyl and carbonyl) of 2-HBP may exhibit different physicochemical behaviors at different temperatures. When the temperature rises to 50°C, 2-HBP molecules may be more active or exhibit higher solubility, allowing them to disperse more uniformly in the resin matrix and possibly form stronger intermolecular interactions with resin molecules. The effect of low-temperature curing: The process of cooling to 4°C may promote the more orderly arrangement or more tightly embedded 2-HBP in the resin matrix. At low temperatures, molecular motion slows down, and 2-HBP may form more stable interactions (such as hydrogen bonds or van der Waals forces) in the resin matrix, thereby improving the material's density. Temperature adjustment promotes increased cross-linking density: The special temperature variation may affect the rate and manner of the resin's cross-linking reaction. At high temperatures (50°C), the reaction rate increases, which may result in looser initial cross-linking of the resin. When the temperature is rapidly reduced to 4°C, the resin molecules may become more compact due to low-temperature curing, forming a more dense network structure. Subsequent warming to room temperature may allow the resin network to further solidify and stabilize, ultimately forming a more uniform and stable cross-linked network, which helps to improve water resistance. The effect of temperature variation on 2-HBP and resin interactions: 2-HBP may interact differently with the resin matrix during temperature changes. When the temperature rises, 2-HBP may be more easily dispersed or dissolved in the resin and re-arranged when the temperature drops, which may promote the uniform distribution of 2-HBP in the resin network, thereby enhancing its strengthening effect on the resin. The generation of a synergistic effect: optimization of multiple interactions: When 2-HBP is combined with temperature variation, a synergistic effect may occur, i.e., the physicochemical properties of 2-HBP at different temperatures interact more favorably with the resin cross-linking reaction. 2-HBP enhances its interaction with the resin at high temperatures and further stabilizes this interaction at low temperatures, resulting in a more dense and stable cross-linked network, thereby significantly improving water resistance. Molecular dynamics regulation: Temperature changes may alter the molecular dynamics environment of the resin, especially during the cross-linking reaction process, the rate and reaction path of molecular motion may be adjusted to a state more conducive to the formation of a high-density cross-linked network. 2-HBP may further improve the water resistance of the cured resin by stabilizing intermediate reaction states or promoting the selection of specific reaction pathways. Improvement of molecular arrangement and density: Special temperature variation may promote the formation of more ordered or denser arrangements of 2-HBP molecules in the resin matrix, thereby reducing microscopic voids or defects. This structural optimization reduces the pathways and spaces for water molecules to penetrate, significantly improving the material's water resistance.Internal stress relief and structural stability: Temperature cycling may help relieve internal stresses generated during the resin curing process, resulting in a more stable internal structure. The presence of 2-HBP may further help optimize this structural stability, ensuring the material's durability in aqueous environments.

[0121] In summary, when 2-hydroxybenzophenone is combined with a specific temperature shift, it is possible to significantly enhance the water resistance of UV-curable resins through a synergistic effect. This synergistic effect may result from changes in the molecular behavior of 2-HBP at different temperatures, optimization of the cross-linking network, enhanced intermolecular interactions, and densification of the microstructure. The temperature shift may promote more effective embedding of 2-HBP into the resin network, leading to a denser, more ordered structure, significantly improving the water resistance of the resin coating.

[0122] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements will not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A nano zinc oxide enhanced UV curable luminous ink, characterized by: The invention comprises the following raw materials in parts by weight: 15-21 parts of nano zinc oxide; 3.6-7.8 parts of 2-hydroxybenzophenone; 78-95 parts of isosorbide dimethyl ether; 18-27 parts of epoxy acrylic resin; 32-38 parts of polyester acrylic resin; 47-65 parts of acrylate; 17-23 parts of luminous powder; 0.6-1.2 parts of defoaming agent; 0.8-2.1 parts of dispersant; 1.4-1.8 parts of leveling agent; and 0.6-0.9 parts of photoinitiator. The preparation method of the nano zinc oxide enhanced UV curable luminous ink comprises the following steps: Step 1: Take luminous powder and nano zinc oxide, add them to isosorbide dimethyl ether, stir and react at room temperature, filter, wash and dry to obtain nano zinc oxide coated with luminous powder; Step 2: adding epoxy acrylic resin, polyester acrylic resin and acrylate mixed with a dispersant to the nano zinc oxide coated with luminous powder, and stirring to obtain a dispersion; Step 3: Ultrasonic dispersion of the dispersion liquid, leveling agent, defoaming agent, and 2-hydroxybenzophenone in step 2 was added, and the temperature was raised to 50-55°C, then lowered to 3-5°C and then raised to room temperature, and a photoinitiator was added, and ultrasonic dispersion was continued; Step 4: Filter to obtain nano zinc oxide enhanced UV curable luminous ink.

2. A method for preparing the nano zinc oxide enhanced UV curable luminous ink according to claim 1, characterized in that: The following steps are involved: Step 1: Take luminous powder and nano zinc oxide, add them to isosorbide dimethyl ether, stir and react at room temperature, filter, wash and dry to obtain nano zinc oxide coated with luminous powder; Step 2: adding epoxy acrylic resin, polyester acrylic resin and acrylate mixed with a dispersant to the nano zinc oxide coated with luminous powder, and stirring to obtain a dispersion; Step 3: Ultrasonic dispersion of the dispersion liquid, leveling agent, defoaming agent, and 2-hydroxybenzophenone in step 2 was added, and the temperature was raised to 50-55°C, then lowered to 3-5°C and then raised to room temperature, and a photoinitiator was added, and ultrasonic dispersion was continued; Step 4: Filter to obtain nano zinc oxide enhanced UV curable luminous ink.

3. The preparation method according to claim 2, characterized in that The first step is specifically as follows: 17-23 parts of luminous powder and 15-21 parts of nano zinc oxide are added to 78-95 parts of isosorbide dimethyl ether, stirred at room temperature for 40-60 minutes, filtered, washed and dried to obtain nano zinc oxide coated with luminous powder.

4. The preparation method according to claim 3, characterized in that Step 2 is specifically as follows: adding 18-27 parts of epoxy acrylic resin, 32-38 parts of polyester acrylic resin and 47-65 parts of acrylate mixed with 0.8-2.1 parts of dispersant to the nano zinc oxide coated with luminous powder, and stirring for 10-25 minutes to obtain a dispersion.

5. The preparation method according to claim 4, characterized in that Step three is as follows: ultrasonically disperse the dispersion of step two, 1.4-1.8 parts of leveling agent, 0.6-1.2 parts of defoaming agent, and 3.6-7.8 parts of 2-hydroxybenzophenone for 2-3 hours, heat to 50-55 ° C and keep warm for 20-30 minutes, cool to 3-5 ° C and keep warm for 20-30 minutes, heat to room temperature, add 0.6-0.9 parts of photoinitiator, and continue ultrasonic dispersion for 1-1.5 hours.

6. The preparation method according to claim 5, characterized in that The pore diameter during filtration in step 4 is 80-100 μm.

7. The preparation method according to claim 6, characterized in that The leveling agent is selected from one or more of BYK333, TEGO450 or LGH7499 leveling agents.

8. The preparation method according to claim 7, characterized in that The dispersant is TEGODispers 685 or TEGODispers 688.

9. The preparation method according to claim 8, characterized in that The particle size of the luminous powder is 50-60 μm.

10. The preparation method according to claim 9, characterized in that The particle size of the nano zinc oxide is 40-50 nm.

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