UV (ultraviolet) silk-screen acid-alkali-resistant impact-resistant tempered sintering ink and preparation method thereof

Abstract

The invention discloses UV (ultraviolet) silk-screen acid-alkali-resistant impact-resistant tempered sintering ink and a preparation method thereof, and belongs to the technical field of ink synthesis. The ink comprises the following components in percentage by mass: 40%-60% of UV varnish, 10%-30% of lead-free glass powder, 5%-15% of silica powder (1-5 [mu] m), 1%-5% of a thiocarbonyl-containing photoinitiator and 0.5%-3% of a polyether modified siloxane / ammonium polycarboxylate compound additive. Lead-free environmental protection and performance breakthrough are realized through gradient particle size filler cooperation, a photoinitiator ortho-chlorine substitution structure and a specific curing process (365 / 405nm LED, 800-1200mJ / cm < 2 >). After the ink is cured, the pencil hardness is more than or equal to 6H, the ink does not fall off after being soaked in 5% hydrochloric acid and 10% sodium hydroxide for 48 hours, the impact strength reaches 42.5 kJ / m < 2 >, the adhesive force is kept at 8.5 MPa after the ink is sintered at 600 DEG C, and the lead content is less than 0.1 ppm. According to the preparation method, the particle size is controlled to be smaller than or equal to 8 microns through three-roller grinding, the viscosity is 2000-5000 cps, and the coating has excellent printability and high-temperature stability and is suitable for corrosion-resistant protective coatings of glass and metal products.

Description

Technical Field

[0001] The present invention relates to the technical field of ink synthesis, and particularly to a UV screen printing acid and alkali resistant, impact resistant tempered sintered ink and its preparation method. Background Art

[0002] Due to its advantages such as high efficiency, energy saving, and low VOC emissions, UV curable inks have been widely used in the screen printing field. However, traditional UV inks have significant deficiencies in terms of resistance to strong acid and strong alkali corrosive media and mechanical impact resistance. Especially in the tempered sintering process (usually requiring high temperature treatment at 400 - 600 °C), problems such as decreased adhesion and embrittlement and cracking are likely to occur. In addition, in order to improve the sintering density and chemical resistance of the ink, lead-containing glass powder is mostly used as an inorganic filler in the prior art. Although the performance can be improved, there is a risk of heavy metal pollution, making it difficult to meet the requirements of increasingly strict environmental protection regulations (such as the EU RoHS directive).

[0003] Currently, the development of lead-free glass powder mostly focuses on low-temperature melting characteristics, but its compatibility with the UV resin system is poor, easily leading to poor ink leveling and uneven dispersion, thereby affecting the fineness of the printed pattern and the density of the sintered coating. At the same time, the photoinitiator system of traditional UV inks is prone to leaving incompletely decomposed small molecule substances during the high-temperature sintering process, resulting in a decrease in the chemical corrosion resistance of the coating. Although attempts have been made in the prior art to improve the mechanical properties by adding reinforcing fillers such as silica powder, due to inaccurate control of the particle size distribution, it is difficult to achieve a balance between impact resistance and surface hardness.

[0004] Therefore, developing a UV screen printing ink that is both lead-free and environmentally friendly, resistant to strong acid and strong alkali corrosion, highly impact resistant, and compatible with the tempered sintering process has become a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a UV screen printing acid and alkali resistant, impact resistant tempered sintered ink and its preparation and curing methods, so as to overcome the significant deficiencies of traditional UV inks in terms of resistance to strong acid and strong alkali corrosive media and mechanical impact resistance, especially the problems such as decreased adhesion and embrittlement and cracking that are likely to occur in the tempered sintering process.

[0006] To solve the above technical problems, the present invention adopts the following technical solutions:

[0007] A UV screen printing acid and alkali resistant, impact resistant tempered sintered ink comprises the following components by mass percentage: 40% - 60% of UV ink vehicle, 10% - 30% of lead-free glass powder, 5% - 15% of silica powder, 1% - 5% of photoinitiator, 0.5% - 3% of environmental protection additive;

[0008] The UV ink varnish is prepared by mixing a solid resin and a UV monomer in a mass ratio of (3 - 1):1;

[0009] The lead-free glass powder contains 30% - 50 wt% of bismuth trioxide;

[0010] The environmental protection additive includes a combination of a polyether-modified silicone leveling agent and an ammonium polycarboxylate dispersant, and the mass ratio of the two is (1 - 2):1.

[0011] Further, the solid resin is epoxy acrylate or polyurethane acrylate.

[0012] Furthermore, the glass transition temperature (Tg) of the solid resin is > 120 °C, the viscosity is controlled at 500 - 2000 mPa·s (25 °C), the cured resin needs to withstand the penetration of 5 wt% hydrochloric acid and 10 wt% NaOH solution, the proportion of hydrophobic groups in the resin is > 30%, and there is no residual hydrophilic ether bond.

[0013] Further, the UV monomer is dipropylene glycol triacrylate or 1,6 - hexanediol diacrylate.

[0014] Furthermore, the structure of the dipropylene glycol triacrylate is:

[0015] Furthermore, the structure of the 1,6 - hexanediol diacrylate is:

[0016] Further, the polyether-modified silicone leveling agent is selected from: BYK - 190, TEGO Dispers 755W, EFKA - 4585, Solsperse 41000; the ammonium polycarboxylate dispersant is selected from: BYK - 333, TEGO Flow 425, EFKA - 3777.

[0017] Further, the lead-free glass powder includes the following components by mass percentage: 35% of SiO2, 20% of B2O3, 25% of ZnO, 5% of Al2O3, 10 wt% of zinc oxide, 5 wt% of zirconium oxide.

[0018] Further, the softening temperature of the lead-free glass powder is 400 - 550 °C, and the particle size distribution D90 ≤ 8 μm.

[0019] Further, the particle size of the silica powder is 1 - 5 μm, and the specific surface area is 2 - 5 m 2 / g.

[0020] Further, the photoinitiator is selected from:

[0021]

[0022]

[0023] Among them, Z1 is selected from: O, S, NR1, CH2; R1 is selected from: methyl, ethyl, propyl.

[0024] Furthermore, the photoinitiator is selected from:

[0025]

[0026]

[0027]

[0028]

[0029] A preparation method of a UV screen printing acid and alkali resistant and impact resistant tempered sintered ink, comprising the following steps:

[0030] a. Stir and dissolve the solid resin and the UV monomer at 40 - 60 °C to form a homogeneous UV ink oil.

[0031] b. Add the lead-free glass powder, the silica powder, the photoinitiator and the environmental protection additive to the product of step a in sequence, and stir at a rate of 800 - 1200 r / min for 20 - 40 minutes.

[0032] c. Grind the mixture with a three-roll grinder for 3 - 5 times, with the roll spacing of 10 - 30 μm, until the particle size ≤ 8 μm.

[0033] d. Adjust the viscosity to 2000 - 5000 cps and the solid content to 70% - 85% to obtain a UV screen printing acid and alkali resistant and impact resistant tempered sintered ink.

[0034] Among them, a UV screen printing acid and alkali resistant and impact resistant tempered sintered ink is cured under ultraviolet conditions.

[0035] Furthermore, the roll temperature of the three-roll grinder in step c is 25 - 35 °C.

[0036] Furthermore, the curing uses an LED cold light source with a peak wavelength of 365 nm or 405 nm, cures at an irradiation energy of 800 - 1200 mJ / cm2, the curing time is 1 - 5 seconds, and the ambient temperature is 20 - 30 °C.

[0037] Furthermore, the pencil hardness of the cured ink layer ≥ 4H, and it has no peeling after being soaked in 5 wt% hydrochloric acid and 10 wt% sodium hydroxide solution for 48 hours.

[0038] An acid- and alkali-resistant and impact-resistant glass or metal product, whose surface is coated with the above-mentioned UV screen printing ink and treated by the above-mentioned curing method to form a sintered coating with a thickness of 10-30 μm.

[0039] The UV ink vehicle component (40%-60%) serves as the core film-forming substance of the system. The UV ink vehicle achieves performance balance through the synergistic effect of solid resin and UV monomer. Epoxy acrylate or polyurethane acrylate, as a solid resin with a high Tg (>120 °C), constructs a rigid three-dimensional cross-linked network. The specific hydrophobic group ratio (>30%) and the ether bond-free molecular design of it effectively block the penetration path of acid and alkali media. Two types of UV monomers, TPGDA and HDDA, not only adjust the system viscosity to the screen printing applicable range (2000-5000 cps), but also form a polymer network with both rigidity and flexibility during the curing process through the complementarity of long-chain flexibility and bifunctional reactivity.

[0040] Lead-free glass powder (10%-30%) This component achieves a double breakthrough in environmental protection and performance through a unique SiO2-B2O3-ZnO-Al2O3-ZrO2 five-element system. The introduction of B2O3 precisely controls the softening point in the range of 400-550 °C, which highly matches the temperature window of the toughening process; the phase transformation toughening-grain boundary strengthening synergistic effect of ZrO2 (5%) and ZnO (25%) enables the impact strength of the coating to reach 42 kJ / m 2 (ASTM D256). The design with a particle size D90 ≤ 8 μm enables it to form a gradient filling structure with silica powder. Observation by SEM shows that the porosity <0.3%, which is 67% lower than that of the conventional formula.

[0041] Silica powder (5%-15%) The selected spherical silica powder with a particle size of 1-5 μm plays a dual role of nano-enhancement and interface optimization in the system. Its specific surface area of 2-5 m 2 / g forms a strong physical adsorption with the resin matrix. Finite element simulation shows that it can disperse more than 60% of the stress concentration. The Si-O-Al chemical bond formed by the reaction with the Al2O3 component in the lead-free glass powder increases the bonding strength between the coating and the metal substrate to 8.5 MPa.

[0042] Photoinitiator system (1%-5%). When Z1 takes the S atom, the molar extinction coefficient of the thioxocarbonyl group at a wavelength of 365 nm reaches 520 L / (mol·cm), which is 3.8 times higher than that of the conventional TPO initiator, achieving 90% curing in 0.5 seconds under 800 mJ / cm 2 irradiation. The steric hindrance effect caused by the ortho-chloro substitution of the benzene ring raises the thermal decomposition temperature of the initiator to 280 °C, avoiding small molecule residues during the sintering process. HPLC detection shows that the residual monomer content after curing <0.3 ppm, fully meeting the food contact material standard.

[0043] The environmentally friendly additives are formulated with (0.5%-3%) polyether-modified silicone leveling agent and ammonium polycarboxylate dispersant to form a "surface-bulk" dual regulation mechanism. The polyether segment (EO / PO = 3:1) in the leveling agent has a polar match with the UV monomer, reducing the surface tension of the ink to 28 mN / m and eliminating the clogging of the screen printing stencil. The dispersant chelates with the hydroxyl groups on the ZnO surface through carboxyl groups and combines with the charge neutralization effect of ammonium ions, stabilizing the Zeta potential of the filler at ±30 mV. After centrifugation test (3000 rpm / 30 min), there is no sedimentation and stratification. Dynamic rheology test shows that the additive combination makes the thixotropic index of the ink reach 6.8, perfectly balancing the printing suitability and leveling performance.

[0044] The system realizes a performance leap through three dimensions: thermodynamically, the thermal expansion coefficients of the glass powder (CTE 7.5×10 -6 / °C) and the resin matrix (CTE 8.2×10 -6 / °C) are matched, so that the residual stress after sintering and cooling at 600 °C is <15 MPa; in terms of chemical stability, the SiO2-Al2O3 network (Knoop hardness of acid resistance 820) and the ZnO-B2O3 phase (mass loss rate of alkali resistance 0.8%) form an acid-base double barrier structure; in terms of mechanical properties, the nano-reinforcement of silica powder and the phase transformation toughening of ZrO2 produce a multiplier effect, so that the pencil hardness of the coating reaches 6H while still maintaining an 8% elongation at break.

[0045] Compared with the prior art, the beneficial effects of the present invention are:

[0046] 1. The synergistic breakthrough of lead-free environmental protection and high-temperature sintering performance: Through the innovative SiO2-B2O3-ZnO-Al2O3-ZrO2 five-component lead-free glass system, while completely eliminating heavy metal pollution (lead content <0.1 ppm), the softening point of 400-550 °C is precisely matched with the toughening process. The synergistic effect of ZrO2 phase transformation toughening and ZnO grain boundary strengthening makes the impact strength of the coating reach 42.5 kJ / m 2 (26.5% higher than that of Comparative Example 2), and the substrate adhesion still remains 8.5 MPa after sintering at 600 °C, breaking the technical bottleneck that lead-free and high-temperature performance cannot be achieved at the same time.

[0047] 2. Construction of an acid-base double barrier protection system: Through the hierarchical design of the SiO2-Al2O3 rigid network (acid resistance hardness 820 HK) and the B2O3-ZnO buffer layer (alkali resistance mass loss rate 0.8%), a double physical and chemical barrier against the penetration of acid-base media is formed. After 48-hour immersion tests in 5 wt% hydrochloric acid and 10 wt% sodium hydroxide, the coating has no swelling and peeling (stratification occurs in Comparative Example 1), and the cross-cut adhesion remains at level 0, and the acid-base resistance life is extended by more than 5 times compared with the traditional formula.

[0048] 3. High-efficiency and low-residue photoinitiator system: The thioxocarbonyl photoinitiator with a specific structure (such as Example 1-A) has a molar extinction coefficient of 520 L / (mol·cm) at 365 nm, achieving 90% curing in 0.68 seconds under 820 mJ / cm 2 irradiation (43% energy saving compared to the TPO system in Comparative Example 1). The ortho-chloro substitution on the benzene ring raises the thermal decomposition temperature to 280 °C. After HPLC detection, the residual monomer in the cured product is <0.3 ppm, and the mass residue rate after sintering at 600 °C reaches 94.2%, completely solving the problem of small molecule precipitation in high-temperature processes.

[0049] 4. Gradient enhancement and interfacial synergistic effect: The 1-5 μm silica powder and the glass powder with D90 ≤ 8 μm form a submicron-micron scale gradient filling. Finite element simulation shows that the stress concentration dispersion efficiency is increased by 60%. Combined with the polyether-modified silicone / polycarboxylic acid ammonium salt additive system (thixotropy index 6.8), while maintaining a 6H pencil hardness, the elongation at break of the ink reaches 8%, achieving a balance between rigidity and flexibility (the hardness of Comparative Example 3 is only 2H), and both the printing suitability and mechanical property indicators exceed the industry standards by more than 30%. Brief Description of the Drawings

[0050] Figure 1 It is the structure of the photoinitiator for the UV screen printing acid and alkali resistant and impact resistant tempered sintered ink of the present invention. Detailed Embodiments

[0051] Next, the technical solutions of the present invention will be clearly and completely described in conjunction with the drawings in the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0052] Example 1-A

[0053]

[0054] Step 1: Compound 1-1 (20 g, 1 eq) and AlCl3 (2 eq) were added to 200 g of dichloromethane. A solution of furan carbonyl chloride (Compound 1-2) (1.2 eq) in 75 ml of dichloromethane was slowly added dropwise. The feeding was carried out at -20 to 10 °C, and the reaction was carried out at room temperature. After the reaction was complete, the reaction solution was slowly poured into 500 ml of 0.1 mol / L HCl at 0 °C, stirred for 30 min, allowed to stand for liquid separation, and the organic phase was retained. The aqueous phase was washed with 50 ml of dichloromethane 2-3 times. The organic phases were combined, 100 ml of 0.1 mol / L sodium bicarbonate solution was added, stirred and shaken, and the pH was adjusted to neutral. The organic phase was retained, dried with 20 g of anhydrous magnesium sulfate, filtered, rotary evaporated, 200 ml of n-heptane was added, stirred for 1-3 h, filtered, and dried to obtain the reaction compound 1-3;

[0055] Step 2: The product of Step 1, Compound 1- (1.0 eq) and AlCl3 (22.08 g, 2.0 eq) were added to 200 g of dichloromethane. Acetyl chloride (7.80 g, 1.2 eq) was slowly added dropwise at 0 °C. The feeding was carried out at -20 to 10 °C, and the reaction was carried out at room temperature. After the reaction was complete, the reaction solution was slowly poured into 500 ml of 0.1 mol / L HCl at 0 °C, stirred for 30 min, allowed to stand for liquid separation, and the organic phase was retained. The aqueous phase was washed with 50 ml of dichloromethane 2-3 times. The organic phases were combined, 100 ml of 0.1 mol / L sodium bicarbonate solution was added, stirred and shaken, and the pH was adjusted to neutral. The organic phase was retained, dried with 20 g of anhydrous magnesium sulfate, filtered, rotary evaporated, and dried to obtain Compound 1-4;

[0056] Step 3: The product of Step 2, Compound 1-4 (1.0 eq), hydroxylamine hydrochloride (8.27 g, 1.5 eq), and sodium acetate (7.00 g, 1.5 eq) were added to 200 g of tetrahydrofuran, and the reaction was carried out for 6-12 h. After the reaction was complete as detected by TLC, the reaction solution was added to 1000 ml of water and left overnight at 0 °C. It was filtered by suction to obtain a powdery solid. The powdery solid was dissolved in 100 ml of ethyl acetate, dried with 20 g of anhydrous magnesium sulfate, filtered, rotary evaporated, and dried to obtain Compound 1-5;

[0057] Step 4: The product of Step 3, Compound 1-5 (1.0 eq) and Compound 1-6 (5.06 g, 1.2 eq) were added to 200 ml of dichloromethane. Triethylamine (8.16 g, 1.5 eq) was slowly added dropwise at 0 °C, and the reaction was carried out at room temperature for 4-6 h. After the reaction was complete, it was slowly added dropwise at 0 °C

[0058] 500 ml of water was stirred for 1 h, allowed to stand for layering, and the organic phase was retained. The pH of the organic phase was then adjusted to neutral with 0.1 mol / L dilute hydrochloric acid, washed once with water, and the organic phase was retained. 30 g of anhydrous magnesium sulfate was added to the organic phase for drying, filtered, and the solvent was rotary evaporated to obtain a viscous liquid with a purity greater than 93%. The viscous liquid was dissolved in 100 ml of ethanol, and then, under high-speed stirring, the ethanol solution was dropped into a larger amount of water to precipitate a white solid product, which was filtered and dried to obtain compound 1-7.

[0059] The MS (MS+1) of compound 1-7: 871.

[0060] The synthesis steps of Examples 1-B to 1-R were different from those of compound 1-2 in step 1 and compound 1-6 in step 3 of Example 1-A. The target compounds in the above formula were prepared by substantially the same method (the same reaction molar ratio and reaction conditions) as in the synthesis of Example 1-A. The specific example structures are shown in Table 1.

[0061] Table 1.

[0062]

[0063]

[0064]

[0065] Example 1

[0066] The mass ratio of a UV screen printing acid- and alkali-resistant and impact-resistant tempered sintered ink is as follows: UV ink vehicle: 55% (epoxy acrylate:TPGDA = 2:1); lead-free glass powder: 25%; silica powder: 10% (particle size 3 μm, specific surface area 3.5 m 2 g); photoinitiator: 4% (compound of Example 1-A); environmental protection additive: 1.5% (BYK-190:BYK-333 = 1.5:1).

[0067] Preparation of a UV screen printing acid- and alkali-resistant and impact-resistant tempered sintered ink: The epoxy acrylate solid resin and dipropylene glycol diacrylate (TPGDA) were mixed at a mass ratio of 2:1 and stirred at 500 r / min for 40 minutes under a constant temperature condition of 50 °C to form a homogeneous UV ink vehicle; then lead-free glass powder (D 90 = 6.5 μm, softening point 480 °C), silica powder (particle size 3 μm, specific surface area 3.5 m 2 / g), the photoinitiator of Example 1-A and environmental protection additives (mass ratio of BYK-190 to BYK-333 is 1.5:1) were dispersed at a high speed of 1000 r / min for 35 minutes; the mixture was transferred to a three-roll mill (roll temperature 30 °C, roll spacing 20 μm) and ground in a cycle for 4 times until the particle size D 90 ≤8 μm; finally, UV monomers were added to adjust the viscosity of the system to 3500 ± 200 cps, and the solid content was controlled to be 78% by vacuum degassing to obtain the UV screen printing acid and alkali resistant and impact resistant tempered sintered ink.

[0068] The UV screen printing acid and alkali resistant and impact resistant tempered sintered ink was cured by irradiating with an LED cold light source with a peak wavelength of 365 nm until it was cured.

[0069] BYK-190 was purchased from: Guangzhou Haoyi New Material Technology Co., Ltd., and BYK-333 was purchased from: BYK Chemie GmbH (BYK).

[0070] Examples 2 - 18

[0071] The formulation and preparation method were the same as those of Example 1, only the photoinitiator was replaced with the corresponding compounds of Examples 1-B to 1-R.

[0072] Comparative Example 1 (conventional photoinitiator)

[0073] The formulation was the same as that of Example 1, but the photoinitiator was replaced with conventional TPO (2,4,6-trimethylbenzoyl diphenylphosphine oxide).

[0074] Comparative Example 2 (lead-containing glass powder)

[0075] The formulation was the same as that of Example 1, but the lead-free glass powder was replaced with a glass powder containing 15% PbO.

[0076] Comparative Example 3 (mismatched additives)

[0077] The formulation was the same as that of Example 1, but the environmental protection additives were replaced with BYK-306 (silicone leveling agent) and BYK-111 (non-ionic dispersant), with a mass ratio of 1.5:1.

[0078] Comparative Example 4 (excessive glass powder particle size)

[0079] The formulation was the same as that of Example 1, but the lead-free glass powder D 90 = 12 μm.

[0080] Performance testing:

[0081] 1. Pencil hardness test:

[0082] Fix the cured ink coating (thickness 20 ± 2 μm) on a horizontal platform; select the hardness grade from pencils ranging from 6H to 6B, and apply a 1 kg load at a 45° angle to uniformly slide across the coating surface; take the highest hardness value without permanent scratches as the test result.

[0083] 2. Acid and alkali resistance test:

[0084] Solutions: 5 wt% HCl (25 °C), 10 wt% NaOH (25 °C);

[0085] Immersion time: 48 hours;

[0086] Completely immerse the specimen (: 50 mm × 50 mm (glass substrate, coating thickness 20 ± 2 μm)) in the solution and keep it at a constant temperature; after taking it out, rinse it with clean water and dry it at room temperature for 24 hours; observe whether the coating shows blistering, peeling or color change, and evaluate the adhesion by the cross-cut method. The peeling area at the scratched part < 5% is qualified.

[0087] 3. Impact resistance test:

[0088] Prepare a coating specimen (substrate is 304 stainless steel plate, size 80 mm × 10 mm × 2 mm, coating thickness 20 ± 2 μm); set the pendulum energy to 5 J and the radius of curvature of the impact edge to 0.8 mm; record the impact energy value (kJ / m 2 ) when the specimen breaks, and take the average value of three tests.

[0089] 4. Adhesion test:

[0090] Cut a 6 × 6 grid on the coating surface down to the substrate; firmly press with 3M tape for 10 seconds and then quickly peel it off; classify according to the proportion of the coating peeling area in the grid area (Grade 0: no peeling; Grade 5: > 65% peeling).

[0091] 5. Lead content detection:

[0092] Take 0.5 g of the ink sample, treat it by microwave digestion (nitric acid + hydrofluoric acid, 180 °C); make the volume up to 50 mL, filter and then inject for analysis; calculate the lead content according to the standard curve, and the detection limit is 0.1 ppm.

[0093] 6. Curing speed test:

[0094] 365 nm LED cold light source (irradiation intensity 1200 mW / cm 2 ), Temperature: 25.0 ± 0.5 °C (constant temperature laboratory), Humidity: 50 ± 3% RH (controlled by dehumidification system).

[0095] Coat the ink evenly on the KBr salt plate and leave it standing in an incubator at 25 °C for 5 minutes; start the LED light source (wavelength 365 ± 2 nm), and at the same time turn on the FTIR for real-time monitoring; collect the characteristic peak area of the C═C double bond at 810 cm -1 at intervals of 0.2 seconds; when the double bond conversion rate reaches 90%, record the cumulative irradiation energy (energy meter model: Thorlabs PM100D); curing time = cumulative irradiation energy / irradiation intensity (1200 mW / cm 2 = 1.2 W / cm 2 ).

[0096] Double bond conversion rate (%) = [1 - (A_t / A_0)] × 100; A_0: the peak area of C═C before curing; A_t: the peak area of C═C at time t.

[0097] 7. High-temperature residue test:

[0098] Condition: nitrogen atmosphere, heating rate 10 °C / min, temperature range 30 - 600 °C;

[0099] Take 10 mg of the cured ink sample and place it in a crucible; record the mass loss rate at 600 °C and calculate the proportion of the residue (%).

[0100] 8. Viscosity and solid content determination:

[0101] Solid content: Take 2 g of the ink sample, leave the sample standing in an incubator at 25 °C for 1 hour, load the rotor, start the viscometer, and record the rotational viscosity (unit: centipoise, cps) when the torque is stable within the range of 10% - 90% of the full scale;

[0102] Coat the ink evenly on an aluminum foil weighing pan, put it into the heating chamber and heat it to 150 °C, start the program until the mass change

[0103] <0.1 mg / 30 s, calculation formula:

[0104] 9. Dispersing stability of environmental protection additives:

[0105] Take 30 mL of the ink sample and put it into a centrifuge tube, leave it standing for 10 minutes to eliminate air bubbles, centrifuge it (3000 rpm, 30 min, 25 ± 0.5 °C) and then it will be stratified. Take the supernatant to measure the solid content and calculate the centrifugal stability:

[0106]

[0107] Dilute the ink to a solid content of 0.1% (to avoid multiple scattering), inject it into the sample cell (temperature: 25 ± 0.1 °C, electric field strength: 40 V / cm, dispersion medium: ultrapure water (conductivity < 0.1 μS / cm)), balance for 5 minutes, and automatically measure it 3 times and take the average value;

[0108] Use the rheometer temperature setting at 25 ± 0.1 °C, and the setting program: 0.1 s -1 (Simulating the static state) → 100 s -1 (Simulating printing shear) → 0.1 s -1 (Recovery), each stage lasts for 60 seconds

[0109] Centrifugal stability > 95%: indicating that the additive achieves super strong anti-settling ability;

[0110] Zeta potential > +24 mV: The high positive potential ensures electrostatic repulsion between particles and prevents flocculation;

[0111] Thixotropic index > 5.8: Excellent shear thinning characteristics, balancing printing suitability and storage stability.

[0112] The performance test data are shown in Table 2 and Table 5.

[0113] The data of pencil hardness test, acid and alkali resistance test, impact resistance test and adhesion test for Examples 1 - 18 and Comparative Examples 1 - 4 are shown in Table 2.

[0114]

[0115]

[0116] The lead content detection and curing speed test tables for Examples 1 - 18 and Comparative Examples 1 - 4 are shown in Table 3.

[0117]

[0118] The high-temperature residue test, viscosity and solid content determination tables for Examples 1 - 18 and Comparative Examples 1 - 4 are shown in Table 4.

[0119]

[0120]

[0121] The determination tables of the dispersion stability of the environmental protection additives for Examples 1 - 18 and Comparative Examples 1 - 4 are shown in Table 5.

[0122] Sample Number Centrifugal Stability (%) Zeta Potential (mV) Thixotropy Index Example 1 98.2 28.5 6.8 Example 2 97.8 27.9 6.5 Example 3 96.5 26.3 6.2 Example 4 95.4 25.1 6 Example 5 98 28.1 6.7 Example 6 97.5 27.2 6.4 Example 7 97.3 26.8 6.3 Example 8 96.8 25.9 6.1 Example 9 98.1 28.3 6.7 Example 10 95.7 24.6 5.9 Example 11 97.6 27.5 6.5 Example 12 96.9 26.1 6.2 Example 13 98.4 29 6.9 Example 14 97.2 26.7 6.4 Example 15 96.3 25.8 6 Example 16 95.1 24 5.8 Example 17 97 26.5 6.3 Example 18 97.4 27.1 6.5 Comparative Example 1 72.5 -15.3 2.1 Comparative Example 2 84.3 12.6 3.7 Comparative Example 3 68.9 -18.7 1.9 Comparative Example 4 85.4 14.2 3.5

[0123] Data of Examples 1-18 show that inks using novel photoinitiators (such as Examples 1-A to 1-R) are significantly superior to traditional formulations in terms of comprehensive performance. In terms of chemical resistance, after being soaked in 5% hydrochloric acid and 10% sodium hydroxide for 48 hours, none of the coatings in all examples peeled off (only slightly yellowed or atomized in some individual cases), and the pencil hardness was stable at 4H-6H, indicating that through the gradient filling of lead-free glass powder (SiO2-B2O3-ZnO-Al2O3-ZrO2 system) and silica powder, a dense acid-base double-barrier structure was formed. The impact strength reached 35.6-43.1 kJ / m 2 , far exceeding 22.3 kJ / m of Comparative Example 1 2 , which benefits from the nano-enhancement effect of silica powder (1-5 μm) and the synergistic effect of phase transformation toughening of ZrO2. In terms of curing performance, the novel photoinitiator enables the double bond conversion rate to reach 87.6%-94.2%, and the curing energy only needs 785-980 mJ / cm 2 (0.65-0.82 seconds), with an efficiency improvement of more than 30% compared to Comparative Example 1 (TPO initiator), and the lead content <0.1 ppm, fully meeting environmental protection regulations.

[0124] Comparative Examples 1-4 highlight the defects of traditional technologies: using the TPO initiator (Comparative Example 1) leads to serious deterioration of acid and alkali resistance (coating dissolution and peeling), and higher curing energy requirements (1200 mJ / cm 2 ); although the lead-containing glass powder (Comparative Example 2) improves the impact resistance (33.6 kJ / m 2 ), there is a risk of heavy metal pollution; improper compatibility of additives (Comparative Example 3) causes dispersion failure, resulting in an adhesion grade of 5 (>65% peeling) and a cliff-like drop in impact resistance (18.7 kJ / m 2 ); while the particle size of the lead-free glass powder exceeds the standard (Comparative Example 4, D90 = 12 μm), leading to an increase in porosity and local peeling of acid resistance. This confirms the core innovation of the present invention - the "surface-bulk" regulation mechanism of a specific photoinitiator structure, environmentally friendly additives (polyether-modified silicone / ammonium polycarboxylate), and the precise control of the glass powder particle size (D90 ≤ 8 μm) and softening point (400-550 °C), which is the key to balancing lead-free environmental protection, corrosion resistance, and mechanical properties.

[0125] Although the embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A UV screen printing acid and alkali resistant and impact resistant tempered sintered ink, characterized in that, It comprises the following components by mass percentage: 40%-60% of UV ink oil, 10%-30% of lead-free glass powder, 5%-15% of silica powder, 1%-5% of photoinitiator, 0.5%-3% of environmental protection auxiliary agent; The UV ink oil is made by mixing solid resin and UV monomer in a mass ratio of (3-1):1; The lead-free glass powder comprises the following components by mass percentage: 35% of SiO2, 20% of B2O3, 25% of ZnO, 5% of Al2O3, 10wt% of zinc oxide, 5wt% of zirconia; The environmental protection auxiliary agent includes a combination of polyether-modified silicone leveling agent and polycarboxylic acid ammonium salt dispersant, and the mass ratio of the two is (1-2):

1.

2. A UV screen printing acid and alkali resistant and impact resistant tempered sintered ink according to claim 1, characterized in that, The solid resin is epoxy acrylate or polyurethane acrylate; The UV monomer is dipropylene glycol diacrylate or 1,6-hexanediol diacrylate.

3. A UV screen printing acid and alkali resistant and impact resistant tempered sintered ink according to claim 1, characterized in that, The polyether-modified silicone leveling agent is selected from: BYK-190, TEGO Dispers 755W, EFKA-4585, Solsperse41000; The polycarboxylic acid ammonium salt dispersant is selected from: BYK-333, TEGO Flow 425, EFKA-3777.

4. A UV screen printing acid and alkali resistant and impact resistant tempered sintered ink according to claim 1, characterized in that, The softening temperature of the lead-free glass powder is 400-550°C, and the particle size distribution D90≤8μm.

5. A UV screen printing acid and alkali resistant and impact resistant tempered sintered ink according to claim 1, characterized in that, The particle size of the fused silica powder is 1-5 μm, and the specific surface area is 2-5 m 2 / g.

6. A UV screen printing acid and alkali resistant and impact resistant tempered sintered ink according to claim 1, characterized in that, The photoinitiator is selected from: wherein, Z1 is selected from: O, S, NR1, CH2; R1 is selected from: methyl, ethyl, propyl.

7. A preparation method of a UV screen printing acid-alkali resistant and impact-resistant tempered sintered ink according to any one of claims 1-6, characterized in that, It includes the following steps: a. Stir and dissolve the solid resin and the UV monomer at 40-60°C to form a homogeneous UV ink oil; b. Sequentially add the lead-free glass powder, the silica powder, the photoinitiator and the environmental protection auxiliary agent to the product of step a, and stir at a rate of 800-1200r / min for 20-40 minutes; c. Grind the mixture 3-5 times with a three-roll grinder, and the roll spacing is 10-30μm until the particle size ≤8μm; d. Adjust the viscosity to 2000-5000cps and the solid content to 70%-85% to obtain a UV screen printing acid and alkali resistant and impact resistant tempered sintered ink; Among them, the UV screen printing acid and alkali resistant and impact resistant tempered sintered ink is cured under ultraviolet conditions.

8. The preparation method of a UV screen printing acid and alkali resistant and impact resistant tempered sintered ink according to claim 7, characterized in that, The roller temperature of the three-roll grinder in step c is 25-35°C.

9. The preparation method of a UV screen printing acid and alkali resistant and impact resistant tempered sintered ink according to claim 7, characterized in that, The curing is carried out using an LED cold light source with a peak wavelength of 365 nm or 405 nm, with an irradiation energy of 800 - 1200 mJ / cm 2 for curing. The curing time is 1 - 5 seconds, and the ambient temperature is 20 - 30 °C.

10. The preparation method of a UV screen printing acid and alkali resistant and impact resistant tempered sintered ink according to claim 7, characterized in that, The pencil hardness of the cured ink layer ≥4H, and it is resistant to immersion in 5wt% hydrochloric acid and 10wt% sodium hydroxide solution for 48 hours without peeling.

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