Environment-friendly water-based high-temperature sintering ink

Abstract

The invention belongs to the technical field of high-temperature sintering ink, and particularly relates to environment-friendly water-based high-temperature sintering ink, which is prepared from the following components in percentage by mass: 15 to 30 percent of modified water-based silane-acrylic acid composite film-forming agent, 30 to 60 percent of high-temperature functional filler, 1 to 5 percent of bio-based dispersing agent, 0.5 to 2 percent of green defoaming agent, 2 to 8 percent of environment-friendly coalescing agent and the balance of deionized water, the printing ink is free of heavy metals and volatile harmful solvents, after the printing ink is sintered at 400-1200 DEG C, a coating and a base material form chemical bonding, and the adhesive force level reaches the first level.

Description

Technical Field

[0001] This invention belongs to the field of high-temperature sintering ink technology, and particularly relates to an environmentally friendly water-based high-temperature sintering ink. Background Technology

[0002] Traditional high-temperature sintering inks mostly rely on solvent-based systems, often containing heavy metal ions and volatile harmful solvents. They not only release large amounts of VOCs during production, application, and sintering, polluting the environment and endangering human health, but also fail to meet stringent environmental standards such as EU REACH and China's GB / T38608-2020. At the same time, the film-forming agents of these inks have poor compatibility with the substrate, and the coating is prone to peeling and cracking after high-temperature sintering. The adhesion level is generally low, making them unsuitable for long-term high-temperature operation.

[0003] Existing high-temperature sintering inks suffer from limited functional design, making it difficult to simultaneously meet diverse needs such as protection, corrosion resistance, conductivity, insulation, and light transmission. Furthermore, they lack adaptability to different substrates such as metals, ceramics, glass, and quartz, often requiring the development of multiple formulations, which increases production and application costs. Some inks also suffer from uneven particle size distribution, poor dispersion stability, and damage to sensitive substrates due to excessively high sintering temperatures, limiting their widespread application in fields such as precision electronics, high-end manufacturing, and chemical equipment. Summary of the Invention

[0004] The purpose of this invention is to address the aforementioned technical problems by providing an environmentally friendly water-based high-temperature sintering ink.

[0005] In view of this, the present invention provides an environmentally friendly water-based high-temperature sintering ink, which, by mass fraction, is composed of the following components: 15%-30% modified water-based silane-acrylic composite film-forming agent, 30%-60% high-temperature functional filler, 1%-5% bio-based dispersant, 0.5%-2% green defoamer, 2%-8% environmentally friendly film-forming aid, and the balance being deionized water;

[0006] The ink is free of heavy metals and volatile harmful solvents. After sintering at 400-1200℃, the coating forms a chemical bond with the substrate, achieving an adhesion level of Grade 1.

[0007] Preferably, the modified waterborne silane-acrylic composite film-forming agent can be replaced with a modified waterborne fluorosilicone-acrylic composite film-forming agent, with a mass fraction maintained at 15%-30%.

[0008] Preferably, the high-temperature functional filler is a combination of nano-sized functional filler and micron-sized bulk filler, wherein the particle size of the nano-sized functional filler is 20nm-80nm, and is selected from at least one of nano-alumina, nano-zirconia, nano-silicon carbide, nano-silicon dioxide, nano-aluminum nitride, nano-tungsten carbide, nano-zinc oxide, nano-silver powder, nano-graphene, nano-iron oxide red, and nano-aluminum fluoride.

[0009] The particle size of the micron-sized bulk filler is 1μm-5μm, and it is selected from at least one of micron-sized silica, micron-sized alumina, micron-sized titanium dioxide, and flake aluminum powder.

[0010] Preferably, the bio-based dispersant is selected from at least one of polyaspartic acid derivatives, sodium lignosulfonate, polycarboxylic acid derivatives, polyethyleneimine, polymaleic anhydride, lignin, polyether derivatives, perfluoropolyether derivatives, and sorbitan monooleate.

[0011] Preferably, the green defoamer is selected from one of the following: organosilicon, polyether, or organosilicon-polyether compound.

[0012] The environmentally friendly film-forming aid is selected from at least one of propylene glycol methyl ether acetate, ethylene glycol butyl ether, dipropylene glycol methyl ether, propylene glycol ethyl ether, ethylene glycol methyl ether, diethylene glycol butyl ether, propylene glycol methyl ether propionate, ethylene glycol propyl ether, dipropylene glycol butyl ether, and environmentally friendly fluorocarbon film-forming aids.

[0013] Preferably, the high-temperature functional filler is surface-modified with an environmentally friendly silane coupling agent, wherein the amount of the environmentally friendly silane coupling agent added is 1%-2.2% of the total mass of the high-temperature functional filler, and the environmentally friendly silane coupling agent is selected from at least one of aminosilane coupling agents, epoxy silane coupling agents, and fluorine-modified silane coupling agents.

[0014] A method for preparing an environmentally friendly water-based high-temperature sintering ink includes the following steps:

[0015] High-temperature functional fillers are mixed with environmentally friendly silane coupling agents for modification, stirred for 20-40 minutes, and then dried for later use.

[0016] Add bio-based dispersant and green defoamer to deionized water, stir to dissolve, then add pretreated high-temperature functional filler and disperse at a high speed of 1000-1600 r / min for 30-55 min.

[0017] The pre-dispersed slurry is fed into a grinding equipment for grinding, and the particle size of the slurry D90 is controlled to be ≤5μm;

[0018] Add modified waterborne silane-acrylic acid composite film-forming agent and environmentally friendly film-forming aid, and stir at a low speed of 500-600 r / min for 60-90 min to adjust the viscosity to 1000-5000 mPa·s;

[0019] The slurry is filtered and allowed to stand for 2-4 hours to defoam, resulting in the finished ink.

[0020] Preferably, the grinding equipment mentioned in step three is a sand mill, a three-roll mill, or a planetary ball mill;

[0021] When using a sand mill, the grinding media should be zirconium beads or high-hardness grinding media, the grinding speed should be 2200-2400 r / min, and the grinding temperature should be ≤40℃.

[0022] When using a planetary ball mill, the ball-to-material ratio is 8:1 and the grinding speed is 300 r / min;

[0023] When using a three-roll mill, the roller speed ratio is 3:1.

[0024] Preferably, the process includes the following steps: substrate pretreatment, ink coating, low-temperature pre-baking, high-temperature sintering, and furnace cooling;

[0025] The low-temperature pre-baking temperature is 80-120℃, and the time is 10-30 minutes;

[0026] The high-temperature sintering temperature is 400-1200℃, and the time is 10-60min;

[0027] The coating method is spraying, screen printing, or roller coating.

[0028] Preferably, the substrates compatible with the ink include metal substrates, ceramic substrates, glass substrates, quartz substrates, and sensitive low-temperature substrates; the metal substrates include stainless steel and aluminum alloys; the function of the ink is selected from at least one of protection, corrosion resistance, decoration, light transmission, conductivity, insulation, and wear resistance, wherein:

[0029] The volume resistivity of conductive ink is ≤1×10⁻⁶ -4 Ω・cm;

[0030] The breakdown voltage of insulating ink is ≥20kV / mm, and the volume resistivity is ≥1×10⁻⁶. 12 Ω・cm;

[0031] The Rockwell hardness of abrasion-resistant inks is ≥HRC60, and the abrasion resistance coefficient (dry friction) is ≤0.08;

[0032] The anti-corrosion ink is resistant to salt spray for ≥500h and to acid and alkali immersion for ≥24h without corrosion;

[0033] The light transmittance of translucent inks is ≥85%.

[0034] The beneficial effects of this invention are:

[0035] This environmentally friendly water-based high-temperature sintering ink is free of heavy metals and volatile harmful solvents throughout the entire process, with extremely low VOC emissions. It fully complies with EU REACH and domestic GB / T38608-2020 environmental standards, achieving green and environmentally friendly practices throughout the entire process from production and application to sintering, effectively reducing harm to the environment and operators. It uses a modified water-based silane-acrylic composite film-forming agent, combined with nano-micro composite high-temperature functional fillers modified with environmentally friendly silane coupling agents. After sintering at 400-1200℃, the coating forms a stable chemical bond with the substrate, achieving an adhesion grade of 1. It also possesses excellent high-temperature stability, density, and durability, and can withstand corresponding temperature conditions for extended periods without cracking or peeling.

[0036] This ink, through differentiated formulation design, can be flexibly adapted to various substrates such as metals, ceramics, glass, quartz, and those sensitive to low temperatures. It simultaneously fulfills diverse functional requirements including protection, corrosion resistance, decoration, light transmission, conductivity, insulation, and abrasion resistance. All functional products meet stringent performance indicators, such as a conductive type with a volume resistivity ≤1×10⁻⁶. -4 The insulation type has a breakdown voltage of ≥20kV / mm, the corrosion-resistant type has a salt spray resistance of ≥500h, and the light transmittance type has a light transmittance of ≥85%. Its preparation process is simple and controllable, the slurry is stably dispersed and has a uniform particle size (D90≤5μm), and the coating methods are flexible and diverse. It not only reduces the production and application costs, but also expands the application scenarios of high-temperature sintering inks in many fields such as precision electronics, high-end manufacturing, chemical equipment, and new energy. Attached Figure Description

[0037] Figure 1 This is a flowchart of an environmentally friendly water-based high-temperature sintering ink according to the present invention. Detailed Implementation

[0038] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0039] A modified waterborne silane-acrylic acid composite film-forming agent is used, which combines the environmental friendliness of waterborne systems with the high-temperature stability of silane materials. After film formation, a dense inorganic-organic hybrid coating can be formed by high-temperature sintering.

[0040] Precise matching of nanoscale functional fillers with micron-scale bulk fillers enhances coating density and functional synergy.

[0041] It incorporates bio-based dispersants and defoamers, and is free of heavy metals and volatile harmful solvents throughout the entire process, complying with EU REACH and domestic GB / T38608-2020 environmental standards;

[0042] It features differentiated formulations that adapt to various substrates (metal, ceramic, glass, quartz). After sintering, the coating forms a chemical bond with the substrate, achieving an adhesion level of 1 (cross-cut test).

[0043] Basic formulation framework (mass fraction): 15%-30% modified waterborne silane-acrylic composite film-forming agent, 30%-60% high-temperature functional filler, 1%-5% bio-based dispersant, 0.5%-2% green defoamer, 2%-8% film-forming aid (environmentally friendly), and deionized water to make up to 100%.

[0044] Preparation process: The surface of the high-temperature functional filler is modified (using an environmentally friendly silane coupling agent) to improve its compatibility with the water-based carrier;

[0045] Mix deionized water, bio-based dispersant, and defoamer, then slowly add the modified functional filler and disperse at high speed for 30-60 minutes.

[0046] The pre-dispersed slurry was fed into a sand mill for grinding, and the particle size D90 was controlled to be ≤5μm.

[0047] Add the modified waterborne silane-acrylic acid composite film-forming agent and film-forming aid, stir at low speed for 60-90 min, and adjust the viscosity to 1000-5000 mPa·s (25℃).

[0048] The ink is obtained by filtering, removing impurities, and allowing it to stand to defoam.

[0049] Sintering process: Substrate pretreatment, ink coating (spraying / screen printing / roll coating), low-temperature pre-baking (80-120℃, 10-30min, to remove moisture and a small amount of additives), high-temperature sintering (400-1200℃, 10-60min, furnace cooling).

[0050] Example 1: General-purpose environmentally friendly water-based high-temperature sintering protective ink for metal substrates (stainless steel);

[0051] Formulation composition (mass fraction): 20% modified waterborne silane-acrylic acid composite film-forming agent, 25% nano alumina (particle size 50nm), 15% micron silica (particle size 2μm), 2% bio-based polyaspartic acid dispersant, 0.8% organosilicon-based environmentally friendly defoamer, 5% propylene glycol methyl ether acetate (environmentally friendly film-forming aid), and 32.2% deionized water.

[0052] Preparation method: Nano-alumina and micron-sized silica are mixed, and environmentally friendly silane coupling agent accounting for 1.5% of the total mass of filler is added. After high-speed stirring for 30 min, the mixture is dried for later use. Bio-based polyaspartic acid dispersant and organosilicon-based environmentally friendly defoamer are added to deionized water and stirred at low speed for 10 min until uniform. The pretreated mixed filler is slowly added, and the speed is adjusted to 1500 r / min for high-speed dispersion for 45 min. The pre-dispersed slurry is fed into a sand mill and ground with zirconium bead grinding media at a grinding speed of 2200 r / min until the particle size D90 = 3.2 μm is reached. Modified waterborne silane-acrylic acid composite film-forming agent and propylene glycol methyl ether acetate are added to the ground slurry. The speed is adjusted to 600 r / min and stirred at low speed for 75 min. The viscosity is measured to be 2500 mPa·s (25℃). The slurry is filtered through a 200-mesh filter to remove impurities and then allowed to stand for defoaming for 2 h to obtain the finished ink.

[0053] Sintering conditions: Pre-drying at 100℃ for 20 min, sintering at 600℃ for 30 min.

[0054] Core performance: VOC emission ≤10g / L; adhesion grade 1 (cross-cut test, ASTM D3359); salt spray resistance (5% NaCl solution) ≥1000h; high temperature resistance 600℃, no cracking or peeling after 100h of continuous use.

[0055] Example 2: High-temperature resistant and corrosion-resistant water-based ink for aluminum alloy substrates;

[0056] Formulation composition (mass fraction): 18% modified waterborne silane-acrylic acid composite film-forming agent, 20% nano-zirconia (particle size 80nm), 10% flake aluminum powder (particle size 5μm), 3% bio-based sodium lignosulfonate dispersant, 1% polyether-based environmentally friendly defoamer, 4% ethylene glycol butyl ether (environmentally friendly film-forming aid), and 44% deionized water.

[0057] Preparation method: Flake aluminum powder is mixed with a special silane coupling agent (2% of the aluminum powder mass), and modified by low-speed stirring for 20 min under inert gas protection, then dried for later use; nano-zirconia is modified separately with the same type of coupling agent and then set aside; bio-based sodium lignin sulfonate dispersant and polyether-based environmentally friendly defoamer are added sequentially to deionized water, stirred and dissolved, then the modified nano-zirconia is added first, dispersed at 1200 r / min for 30 min, then the modified flake aluminum powder is added, and the speed is adjusted to 1000 r / min for 20 min; the slurry is fed into a sand mill for grinding, controlling the grinding temperature ≤40℃, until the particle size D90=4.5μm; the modified water-based silane-acrylic acid composite film-forming agent and ethylene glycol butyl ether are added, and the mixture is stirred at low speed at 500 r / min for 80 min, adjusting the viscosity to 3000 mPa·s; the mixture is filtered through a 180-mesh filter, allowed to stand for defoaming for 3 h, and then packaged as a finished product.

[0058] Sintering conditions: Pre-drying at 90℃ for 25 min, sintering at 500℃ for 40 min.

[0059] Core performance: Compatible with aluminum alloy anodizing; resistant to corrosion after 24 hours of immersion in acid and alkali solutions (10% H2SO4, 10% NaOH); adhesion grade 1; high temperature resistance up to 500℃; resistant to damp heat (40℃ / 95%RH) for ≥500 hours.

[0060] Example 3: High-temperature decorative water-based ink (black) for ceramic substrates;

[0061] Formulation composition (mass fraction): 22% modified waterborne silane-acrylic composite film-forming agent, 15% nano silicon carbide (particle size 40nm), 20% black high-temperature inorganic pigment (chrome iron black), 2.5% bio-based polycarboxylic acid dispersant, 1.2% organosilicon-polyether compound defoamer, 6% dipropylene glycol methyl ether (environmentally friendly film-forming aid), and 33.3% deionized water.

[0062] Preparation method: Black high-temperature inorganic pigment (chrome iron black) and nano silicon carbide are mixed at a mass ratio of 4:3. Environmentally friendly silane coupling agent (accounting for 2% of the mass of the mixed powder) is added. The mixture is mixed at 1800 r / min for 40 min in a high-speed mixer, dried, and then pulverized. Bio-based polycarboxylic acid dispersant and organosilicon-polyether compound defoamer are added to deionized water and stirred evenly. The blended modified powder is then slowly added and dispersed at 1400 r / min for 50 min. A three-roll mill is used, and the roller spacing is adjusted to grind the slurry multiple times until the particle size D90 = 2.8 μm. During this period, a small amount of deionized water is added to prevent drying. Modified waterborne silane-acrylic acid composite film-forming agent and dipropylene glycol methyl ether are added and stirred at 600 r / min for 70 min to achieve a viscosity of 2000 mPa·s. The mixture is filtered twice through a 200-mesh filter and allowed to stand for 2.5 h to defoam. The material is then discharged after ensuring that there are no bubbles.

[0063] Sintering conditions: Pre-drying at 120℃ for 15 min, sintering at 800℃ for 20 min.

[0064] Core performance: Uniform color, color difference ΔE≤1.0; adhesion grade 0; abrasion resistance (500g load, cotton cloth wiping) ≥500 times without exposing the base material; high temperature resistance 800℃, no discoloration or delamination.

[0065] Example 4: High-temperature transparent water-based ink for glass substrate;

[0066] Formulation composition (mass fraction): 25% modified waterborne silane-acrylic acid composite film-forming agent, 18% nano silica (particle size 20nm), 10% low melting point glass powder (softening point 450℃), 1.5% bio-based sorbitan monooleate dispersant, 0.5% environmentally friendly silicone defoamer, 4% propylene glycol ethyl ether (environmentally friendly film-forming aid), and 41% deionized water.

[0067] Preparation method: Nano-silica was modified with an aminosilane coupling agent (1% by mass), and low-melting-point glass powder was modified with an epoxysilane coupling agent (1.2% by mass). After drying, it was ready for use. Bio-based sorbitan monooleate dispersant and environmentally friendly organosilicon defoamer were added to deionized water and stirred to dissolve. The modified nano-silica was added first and dispersed at 1300 r / min for 35 min. Then the modified low-melting-point glass powder was added and dispersed at 1100 r / min for 25 min. The mixture was ground in a sand mill using ultrafine zirconium beads. The grinding time was controlled within 60 min to ensure that the particle size D90 = 2.0 μm and to avoid damaging the glass powder structure. Modified waterborne silane-acrylic acid composite film-forming agent and propylene glycol ethyl ether were added and stirred at low speed of 550 r / min for 85 min to adjust the viscosity to 1500 mPa·s. The mixture was then filtered through a 300-mesh filter and allowed to stand for 4 h to defoam, so as to avoid impurities affecting light transmittance.

[0068] Sintering conditions: Pre-drying at 80℃ for 30 min, sintering at 550℃ for 25 min.

[0069] Core performance: Light transmittance ≥85% (coating thickness 10μm); adhesion grade 1 (no peeling after cross-cut test); no fogging after boiling in water (100℃) for 2 hours; high temperature resistance 550℃, light transmittance retention ≥98%.

[0070] Example 5: High-temperature conductive water-based ink (metal substrate);

[0071] Formulation composition (mass fraction): 15% modified waterborne silane-acrylic acid composite film-forming agent, 40% nano silver powder (particle size 50nm), 5% nano graphene (5-10 layers), 4% bio-based polyethyleneimine dispersant, 1.5% polyether defoamer, 3% ethylene glycol methyl ether (environmentally friendly film-forming aid), and 31.5% deionized water.

[0072] Preparation method: Nano-silver powder and nano-graphene are mixed at an 8:1 ratio. An environmentally friendly antioxidant (0.8% of the mixed powder mass) and a silane coupling agent (1.5%) are added. The mixture is modified by low-speed stirring in a vacuum environment for 30 min to prevent silver powder oxidation. Bio-based polyethyleneimine dispersant and polyether defoamer are added to deionized water and stirred evenly. Modified conductive filler is slowly added under inert gas protection and dispersed at high speed at 1600 r / min for 55 min to ensure uniform dispersion and no agglomeration of the filler. The mixture is then ground in a sand mill at a controlled grinding pressure of 0.3 MPa and circulated until the particle size D90 = 3.5 μm. Modified waterborne silane-acrylic acid composite film-forming agent and ethylene glycol methyl ether are added and stirred at 500 r / min for 90 min to adjust the viscosity to 3500 mPa·s. The mixture is filtered through a 200-mesh filter, defoamed under vacuum for 2 h, and vacuum-sealed to prevent a decrease in conductivity.

[0073] Sintering conditions: Pre-drying at 110℃ for 20 min, sintering at 650℃ for 30 min.

[0074] Core performance: Volume resistivity ≤1×10 -4 Ω·cm; Adhesion grade 1; Stable performance under high and low temperature cycling (-50℃-600℃, 10 cycles); Resistivity resistance ≥300h, resistivity change rate ≤5%.

[0075] Example 6: High-temperature resistant insulating water-based ink for quartz substrate;

[0076] Formulation composition (mass fraction): 23% modified waterborne silane-acrylic acid composite film-forming agent, 22% nano aluminum nitride (particle size 60nm), 12% micron titanium dioxide (particle size 1μm), 3% bio-based polymaleic anhydride dispersant, 1% organosilicon defoamer, 5% diethylene glycol butyl ether (environmentally friendly film-forming aid), and 34% deionized water.

[0077] Preparation method: Nano-aluminum nitride and micron-sized titanium dioxide are mixed, and an environmentally friendly silane coupling agent (accounting for 2% of the mass of the mixed powder) is added. The mixture is mixed at 2000 r / min for 35 min in a high-speed mixer, dried, and then passed through a 100-mesh sieve. Bio-based polymaleic anhydride dispersant and organosilicon defoamer are added to deionized water, stirred and dissolved, and then modified mixed filler is added. The mixture is dispersed at 1400 r / min for 40 min. The mixture is then ground using a planetary ball mill with a ball-to-material ratio of 8:1 and a grinding speed of 300 r / min until the particle size D90 = 4.0 μm is reached. Modified waterborne silane-acrylic acid composite film-forming agent and diethylene glycol butyl ether are added, and the mixture is stirred at 600 r / min for 70 min to adjust the viscosity to 2800 mPa·s. The mixture is then filtered through a 200-mesh filter, allowed to stand for 3 h to defoam, and discharged after the insulation performance is tested and found to be qualified.

[0078] Sintering conditions: Pre-drying at 120℃ for 15 min, sintering at 1000℃ for 20 min.

[0079] Core performance: Breakdown voltage ≥ 20kV / mm; Volume resistivity ≥ 1×10 12 Ω·cm; high temperature resistance up to 1000℃, insulation performance retention rate ≥90%; adhesion level 1.

[0080] Example 7: High-temperature abrasion-resistant water-based ink (substrate for mechanical parts);

[0081] Formulation composition (mass fraction): 17% modified waterborne silane-acrylic acid composite film-forming agent, 28% nano tungsten carbide (particle size 50nm), 15% micron alumina (particle size 3μm), 3.5% bio-based lignin dispersant, 1.3% defoamer, 5% propylene glycol methyl ether propionate (environmentally friendly film-forming aid), and 30.2% deionized water.

[0082] Preparation method: Nano-tungsten carbide and micron-sized alumina are mixed and fed into a plasma modification device, where they are treated under an argon atmosphere for 20 minutes to enhance surface activity. Bio-based lignin dispersant and defoamer are added to deionized water and stirred evenly. Then, the modified wear-resistant filler is slowly added and dispersed at a high speed of 1500 r / min for 50 minutes, with small amounts of deionized water added in stages to prevent the slurry from becoming too thick. The slurry is then ground in a sand mill using high-hardness grinding media at a grinding speed of 2400 r / min until the particle size D90 = 4.2 μm. Modified waterborne silane-acrylic acid composite film-forming agent and propylene glycol methyl ether propionate are added and stirred at 550 r / min for 80 minutes to adjust the viscosity to 4000 mPa·s. The mixture is then filtered through a 180-mesh filter and allowed to stand for 2.5 hours to defoam, yielding the high-wear-resistant ink product.

[0083] Sintering conditions: Pre-drying at 100℃ for 25 minutes, sintering at 700℃ for 35 minutes.

[0084] Core performance: Rockwell hardness ≥ HRC60; wear resistance coefficient (dry friction) ≤ 0.08; coating wear after 1000 friction cycles (500g load) ≤ 5μm; high temperature resistance up to 700℃, with no significant decrease in wear resistance.

[0085] Example 8: Low-temperature sintering type environmentally friendly water-based ink (sensitive substrate);

[0086] Formulation composition (mass fraction): 28% modified waterborne silane-acrylic acid composite film-forming agent, 18% nano zinc oxide (particle size 30nm), 12% low melting point borosilicate glass powder (softening point 380℃), 2% bio-based polyether dispersant, 0.8% defoamer, 7% ethylene glycol propyl ether (environmentally friendly film-forming aid), and 32.2% deionized water.

[0087] Preparation method: Nano zinc oxide is mixed with low-melting-point borosilicate glass powder, and an environmentally friendly silane coupling agent (accounting for 1.8% of the mixed powder mass) is added. After stirring at low speed for 25 min, the mixture is dried to prevent the glass powder from softening prematurely. Bio-based polyether dispersant and defoamer are added to deionized water, stirred and dissolved, and then the co-modified powder is added. The mixture is dispersed at high speed of 1200 r / min for 35 min. The mixture is then ground at low temperature in a sand mill (cooling water is circulated in the grinding chamber, and the temperature is ≤35℃) until the particle size D90=3.0μm. Modified waterborne silane-acrylic acid composite film-forming agent and ethylene glycol propyl ether are added, and the mixture is stirred at low speed of 600 r / min for 65 min to adjust the viscosity to 2200 mPa·s. The mixture is filtered through a 200-mesh filter and allowed to stand for 3 h to defoam, ensuring that the ink meets the requirements of low-temperature sintering.

[0088] Sintering conditions: Pre-drying at 80℃ for 20 min, sintering at 400℃ for 40 min.

[0089] Core performance: Compatible with substrates that are not resistant to high temperatures (such as some plastic alloys and low-temperature ceramics); adhesion level 1; salt spray resistance ≥500h; high temperature resistance 400℃, no cracking or discoloration.

[0090] Example 9: High corrosion resistance and high temperature water-based ink (chemical equipment substrate);

[0091] Formulation composition (mass fraction): 24% modified waterborne fluorosilicone-acrylic composite film-forming agent, 20% nano aluminum fluoride (particle size 70nm), 16% micron silica (particle size 2μm), 3% bio-based perfluoropolyether dispersant, 1.5% defoamer, 6% environmentally friendly fluorocarbon film-forming aid, and 29.5% deionized water.

[0092] Preparation method: Nano-sized aluminum fluoride and micron-sized silica are mixed, and a fluorinated silane coupling agent (accounting for 2.2% of the mixed powder mass) is added. The mixture is then mixed at 1800 r / min for 40 min in a dry environment and dried for later use. Bio-based perfluoropolyether dispersant and defoamer are added to deionized water and stirred evenly. Modified corrosion-resistant filler is then slowly added and dispersed at 1500 r / min for 50 min. The mixture is then ground in a sand mill, and the grinding time is controlled to the particle size D90=3.8μm. The stability of the slurry is monitored during the process. Modified waterborne fluorosilicone-acrylic composite film-forming agent and environmentally friendly fluorocarbon film-forming aid are added and stirred at 500 r / min for 85 min. The viscosity is adjusted to 3200 mPa·s. The mixture is then filtered through a 200-mesh filter and vacuum defoamed for 2 h to ensure uniform dispersion of the corrosion-resistant components of the ink.

[0093] Sintering conditions: Pre-drying at 110℃ for 20 min, sintering at 750℃ for 30 min.

[0094] Core performance: Resistant to strong acids and alkalis (30% H2SO4, 20% NaOH solution) for 72 hours without corrosion; resistant to organic solvents (ethanol, acetone) for 48 hours without swelling; adhesion grade 1; high temperature resistance up to 750℃, with stable corrosion resistance.

[0095] Example 10: Colored high-temperature decorative water-based ink (red, suitable for ceramics / metals);

[0096] Formulation composition (mass fraction): 21% modified waterborne silane-acrylic acid composite film-forming agent, 22% nano iron oxide red (particle size 40nm), 13% micron silica (particle size 1.5μm), 2.2% bio-based polycarboxylic acid dispersant, 1% defoamer, 5% dipropylene glycol butyl ether (environmentally friendly film-forming aid), and 35.8% deionized water.

[0097] Preparation method: Nano-iron oxide red and micron-sized silica are mixed, and an environmentally friendly silane coupling agent (accounting for 1.6% of the mixed powder mass) is added. The mixture is stirred at high speed for 30 min to ensure uniform pigment coating. Bio-based polycarboxylic acid dispersant and defoamer are added to deionized water and stirred until dissolved. Then, co-modified powder is added and dispersed at high speed at 1400 r / min for 45 min to improve pigment dispersibility and avoid color difference. A three-roll mill is used with the roller speed ratio adjusted to 3:1, and the mixture is ground multiple times until the particle size D90=2.5μm to ensure sufficient pigment refinement. Modified waterborne silane-acrylic acid composite film-forming agent and dipropylene glycol butyl ether are added and stirred at low speed at 600 r / min for 70 min to adjust the viscosity to 1800 mPa·s. The mixture is filtered twice through a 200-mesh filter, allowed to stand for 3 h to defoam, and discharged after the color uniformity is tested and found to be qualified.

[0098] Sintering conditions: Pre-baking at 100℃ for 20 min, sintering at 650℃ for 25 min (metal substrate), 850℃ for 20 min (ceramic substrate).

[0099] Core performance: Bright colors, color difference ΔE≤1.2; adhesion grade 1; no fading after ≥1000h of sunlight exposure (xenon lamp aging); high temperature resistance 650-850℃, color retention rate ≥95%.

[0100] The embodiments of this application have been described above with reference to the accompanying drawings. Unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other. This application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.

Claims

1. An environmentally friendly water-based high-temperature sintering ink, characterized in that: By mass fraction, it consists of the following components: 15%-30% modified waterborne silane-acrylic composite film-forming agent, 30%-60% high-temperature functional filler, 1%-5% bio-based dispersant, 0.5%-2% green defoamer, 2%-8% environmentally friendly film-forming aid, and the balance being deionized water; The ink is free of heavy metals and volatile harmful solvents. After sintering at 400-1200℃, the coating forms a chemical bond with the substrate, achieving an adhesion level of Grade 1.

2. The environmentally friendly water-based high-temperature sintering ink according to claim 1, characterized in that: The modified waterborne silane-acrylic composite film-forming agent can be replaced with a modified waterborne fluorosilicone-acrylic composite film-forming agent, with a mass fraction maintained at 15%-30%.

3. The environmentally friendly water-based high-temperature sintering ink according to claim 1, characterized in that: The high-temperature functional filler is a combination of nano-sized functional filler and micron-sized bulk filler, wherein the particle size of the nano-sized functional filler is 20nm-80nm and is selected from at least one of nano-alumina, nano-zirconia, nano-silicon carbide, nano-silicon dioxide, nano-aluminum nitride, nano-tungsten carbide, nano-zinc oxide, nano-silver powder, nano-graphene, nano-iron oxide red, and nano-aluminum fluoride. The particle size of the micron-sized bulk filler is 1μm-5μm, and it is selected from at least one of micron-sized silica, micron-sized alumina, micron-sized titanium dioxide, and flake aluminum powder.

4. The environmentally friendly water-based high-temperature sintering ink according to claim 1, characterized in that: The bio-based dispersant is selected from at least one of polyaspartic acid derivatives, sodium lignosulfonate, polycarboxylic acid derivatives, polyethyleneimine, polymaleic anhydride, lignin, polyether derivatives, perfluoropolyether derivatives, and sorbitan monooleate.

5. The environmentally friendly water-based high-temperature sintering ink according to claim 1, characterized in that: The green defoamer is selected from one of the following: organosilicon, polyether, or organosilicon-polyether compound. The environmentally friendly film-forming aid is selected from at least one of propylene glycol methyl ether acetate, ethylene glycol butyl ether, dipropylene glycol methyl ether, propylene glycol ethyl ether, ethylene glycol methyl ether, diethylene glycol butyl ether, propylene glycol methyl ether propionate, ethylene glycol propyl ether, dipropylene glycol butyl ether, and environmentally friendly fluorocarbon film-forming aids.

6. The environmentally friendly water-based high-temperature sintering ink according to claim 1, characterized in that: The high-temperature functional filler is surface modified with an environmentally friendly silane coupling agent. The amount of the environmentally friendly silane coupling agent added is 1%-2.2% of the total mass of the high-temperature functional filler. The environmentally friendly silane coupling agent is selected from at least one of aminosilane coupling agents, epoxy silane coupling agents, and fluorine-modified silane coupling agents.

7. A method for preparing an environmentally friendly water-based high-temperature sintering ink, based on the environmentally friendly water-based high-temperature sintering ink according to any one of claims 1-6, characterized in that: Includes the following steps: High-temperature functional fillers are mixed with environmentally friendly silane coupling agents for modification, stirred for 20-40 minutes, and then dried for later use. Add bio-based dispersant and green defoamer to deionized water, stir to dissolve, then add pretreated high-temperature functional filler and disperse at a high speed of 1000-1600 r / min for 30-55 min. The pre-dispersed slurry is fed into a grinding equipment for grinding, and the particle size of the slurry D90 is controlled to be ≤5μm; Add modified waterborne silane-acrylic acid composite film-forming agent and environmentally friendly film-forming aid, and stir at a low speed of 500-600 r / min for 60-90 min to adjust the viscosity to 1000-5000 mPa·s; The slurry is filtered and allowed to stand for 2-4 hours to defoam, resulting in the finished ink.

8. The method for preparing an environmentally friendly water-based high-temperature sintering ink according to claim 7, characterized in that: The grinding equipment mentioned in step three is a sand mill, a three-roll mill, or a planetary ball mill; When using a sand mill, the grinding media should be zirconium beads or high-hardness grinding media, the grinding speed should be 2200-2400 r / min, and the grinding temperature should be ≤40℃. When using a planetary ball mill, the ball-to-material ratio is 8:1 and the grinding speed is 300 r / min; When using a three-roll mill, the roller speed ratio is 3:

1.

9. The method for preparing an environmentally friendly water-based high-temperature sintering ink according to claim 7, characterized in that: Includes the following steps: Substrate pretreatment, ink coating, low-temperature pre-baking, high-temperature sintering, and furnace cooling; The low-temperature pre-baking temperature is 80-120℃, and the time is 10-30 minutes; The high-temperature sintering temperature is 400-1200℃, and the time is 10-60min; The coating method is spraying, screen printing, or roller coating.

10. The method for preparing an environmentally friendly water-based high-temperature sintering ink according to claim 7, characterized in that: The substrates compatible with the ink include metal substrates, ceramic substrates, glass substrates, quartz substrates, and sensitive low-temperature substrates; the metal substrates include stainless steel and aluminum alloys; the function of the ink is selected from at least one of the following: protection, corrosion resistance, decoration, light transmission, conductivity, insulation, and wear resistance. The volume resistivity of conductive ink is ≤1×10⁻⁶ -4 Ω・cm; The breakdown voltage of insulating ink is ≥20kV / mm, and the volume resistivity is ≥1×10⁻⁶. 12 Ω・cm; The Rockwell hardness of abrasion-resistant inks is ≥HRC60, and the abrasion resistance coefficient (dry friction) is ≤0.08; The anti-corrosion ink is resistant to salt spray for ≥500h and to acid and alkali immersion for ≥24h without corrosion; The light transmittance of translucent inks is ≥85%.

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