A low-temperature fast-cured paste for intelligent dimming electrode and a preparation method thereof

Abstract

This invention provides a low-temperature rapid curing slurry for intelligent dimming electrodes and its preparation method. The slurry comprises, by mass percentage: 30-60% flake silver powder, 10-30% spherical silver powder, 1-10% nano silver powder, 6-22% organic resin, 1-6% curing agent, 0.2-3% additives, and 0.1-10% solvent. The solvent is a low-to-medium boiling range mixed solvent formed by mixing low-boiling-point, medium-boiling-point, and high-boiling-point solvents, with a mass ratio of (3.5-4.5):(2.5-3.5):(1.5-2.5). The curing agent is a latent isocyanate curing agent with a desealing temperature less than or equal to 80°C. The slurry of this invention is not only suitable for dispensing processes but also exhibits good and stable screen printing performance, a wide operating window, and can meet short-time curing requirements below 100°C. Furthermore, it demonstrates good adhesion and high reliability at multiple interfaces such as PET, ITO glass, PI, and PVDF.

Description

Technical Field

[0001] This invention belongs to the technical field of conductive pastes for intelligent dimming technology, and particularly relates to a low-temperature rapid curing paste for intelligent dimming electrodes and its preparation method. Background Technology

[0002] Intelligent dimming is a technology that dynamically adjusts parameters such as brightness, color temperature, and transmittance of lighting / display devices by triggering signals such as electricity, light, and sound. Its core principle is "adapting to the environment and needs as required." Intelligent dimming technology has various applications in architectural glass, automotive windows, retail displays, and electronic devices, providing functions such as privacy control, light modulation, glare reduction, and energy efficiency. Conductive materials play a crucial role in the field of intelligent dimming, directly affecting the response speed, stability, and energy consumption of dimming films. Low-temperature silver paste, as a novel conductive material, is gradually becoming a research hotspot and a new favorite in the field of dimming films due to its unique performance advantages. The electrodes formed after the low-temperature silver paste has solidified serve two purposes: firstly, to construct stable conductive circuits, transmitting driving current for the oriented alignment of liquid crystal molecules and improving dimming efficiency; secondly, they can serve as electrode lead-out structures, enabling stable connection to an external power source.

[0003] Traditional silver pastes typically require sintering at high temperatures, which poses a significant limitation for some heat-sensitive substrates. Silver pastes used in smart dimming technology need to be sintered or cured at around 120℃-150℃ to be compatible with heat-sensitive substrates such as PET and ITO; moreover, the sintered paste should have low resistivity and high conductivity to allow the dimming film to respond quickly to electrical signals. Currently, most low-temperature silver pastes available for screen printing have a curing temperature of 120℃-150℃ and require more than 30 minutes, leading to increased energy consumption and low production efficiency.

[0004] It also has strong adhesion and good flexibility. For example, when used in automotive dimming films, it can withstand vibrations and mechanical stress during driving and has high weather resistance. Summary of the Invention

[0005] In view of this, the present invention provides a low-temperature rapid curing slurry for intelligent dimming electrodes and its preparation method. The slurry is not only suitable for dispensing processes, but also has good and stable screen printing performance, a wide operating window, and can meet the requirements of short-time curing at temperatures below 100°C. Moreover, it has good adhesion and high reliability at multiple interfaces such as PET, ITO glass, PI, and PVDF.

[0006] To achieve the above objectives, the technical solution of the present invention is as follows: A low-temperature rapid curing slurry for intelligent dimming electrodes comprises, by weight percentage: 30-60% flake silver powder, 10-30% spherical silver powder, 1-10% nano silver powder, 6-22% organic resin, 1-6% curing agent, 0.2-3% additives, and 0.1-10% solvent; The mass fraction of the flake silver powder can be 30%, 46%, 52%, 59.4%, or 60%; the mass fraction of the spherical silver powder can be 10%, 11.5%, 14.85%, 13%, or 30%; the mass fraction of the nano silver powder can be 1%, 4.4%, 5%, 5.7%, or 10%; the mass fraction of the organic resin can be 6%, 6.7%, 12%, 15%, 16%, 21.7%, or 22%; the mass fraction of the curing agent can be 1%, 1.35%, 2%, 3%, 4.4%, or 6%; the mass fraction of the additives can be 0.2% or 3%; and the mass fraction of the solvent can be 1%, 9%, or 10%. The medium-to-low boiling range mixed solvent is formed by mixing low-boiling-point solvent, medium-boiling-point solvent and high-boiling-point solvent. The mass ratio of high-boiling-point solvent, medium-boiling-point solvent and low-boiling-point solvent is (3.5-4.5):(2.5-3.5):(1.5-2.5); wherein, low-boiling-point solvent refers to solvent with a normal boiling point of 80℃~130℃, medium-boiling-point solvent refers to solvent with a normal boiling point of 130℃~180℃, and high-boiling-point solvent refers to solvent with a normal boiling point of 180℃~250℃. The curing agent is a latent isocyanate curing agent with a desealing temperature of less than or equal to 80°C.

[0007] The technical challenge of this invention lies in balancing the stability of screen printing with the high activity of low-temperature short-time curing. It is necessary to ensure that when the screen printing paste is exposed over a large area for a long time, there will be no large amount of solvent evaporation or premature reaction leading to increased viscosity or screen clogging. At the same time, it is also necessary to meet the requirement that curing can be completed in as little as 10 minutes, and achieve high conductivity, qualified adhesion and good durability.

[0008] To solve these kinds of technical problems, it is necessary to strike a balance between the two key indicators of stability and responsiveness.

[0009] This invention uses a specific solvent and adjusts the ratio to precisely regulate the boiling range of the system. This not only ensures rapid evaporation at low temperatures and short durations, but also prevents excessive viscosity growth during long-term printing, which could affect the printing effect. Furthermore, it requires that the solvent not react with the organic resins or additives in the system beforehand.

[0010] This invention also employs a highly stable, ultra-low temperature unsealing latent isocyanate curing agent. Before the system temperature reaches the unsealing temperature, the curing agent remains chemically stable, effectively preventing premature reactions and screen clogging during the printing process. When the curing stage reaches 80°C, the curing agent rapidly unseales and, possessing a multifunctional structure, simultaneously exposes multiple reactive sites, significantly increasing the probability of collision reactions with resin functional groups. This results in a faster curing rate and ultimately forms a dense interpenetrating network structure, effectively reducing system resistivity and significantly improving the product's ability to withstand stringent reliability tests.

[0011] Therefore, by mixing specific solvents, curing agents, and flake, spherical, and nano silver powders, the slurry of the present invention can be cured for 10 minutes at temperatures below 100°C.

[0012] Preferably, the mass ratio of the high-boiling-point solvent, the medium-boiling-point solvent, and the low-boiling-point solvent is 4:3:2.

[0013] Preferably, the low-boiling-point solvent is selected from: dimethyl carbonate and / or butyl acetate; the medium-boiling-point solvent is selected from: amyl acetate and / or propylene glycol methyl ether acetate; the high-boiling-point solvent is selected from: any one or a mixture of several of diethylene glycol butyl ether, diethylene glycol ethyl ether, divalent esters, diethylene glycol butyl ether acetate, or isophorone.

[0014] Preferably, the latent isocyanate curing agent is any one or a mixture of several of toluene diisocyanate, hexamethylene diisocyanate, or polydiphenylmethane diisocyanate.

[0015] Preferably, the product comprises, by weight percentage: 46-60% flake silver powder, 11-15% spherical silver powder, 4-6% nano silver powder, 6.7-22% organic resin, 1.3-4.4% curing agent, 3% additives, and 9% organic solvent.

[0016] Preferably, the flake silver powder has a D50 particle size of 3.0-5.0 μm and a D100 ≤ 11 μm; the spherical silver powder has a D50 particle size range of 0.3-1.0 μm and a D100 ≤ 3 μm; and the nano silver powder has an average particle size of < 0.1 μm.

[0017] Preferably, the organic resin is selected from one or a mixture of several of modified epoxy resin, acrylic resin, polyurethane resin or modified polyester resin derivatives.

[0018] Preferably, the additives include any one or more of thixotropic agents, leveling agents, dispersants, and coupling agents; The thixotropic agent is selected from one or more of fumed silica, organobentonite, hydrogenated castor oil, polyamide wax, polyurea, or organic urea. The leveling agent is selected from one or more of acrylic and modified polysiloxane types; The dispersant is selected from one or more of sulfonates, ammonium salts, carboxylates, and polyphosphates; The preferred silane coupling agent is one or more of aminosilane coupling agents, epoxy-terminated silane coupling agents, titanate coupling agents, or aluminate coupling agents.

[0019] A second aspect of the present invention provides a method for preparing a low-temperature rapid curing slurry for a smart dimming electrode, comprising the following steps: According to the formula, the organic resin, additives and solvent are stirred and mixed in the reactor, and the temperature is controlled at 20-35℃. Then, nano silver powder, flake silver powder and spherical silver powder are added in sequence and stirred for 100-120 minutes to obtain a uniform coarse slurry. Then, the coarse slurry is ground with a three-roll mill to obtain a uniformly dispersed finished slurry.

[0020] Preferably, the grinding process employs a method of gradually reducing the roller gap, with the roller gap being adjusted sequentially from 120μm to 5μm.

[0021] Because the present invention adopts the above technical solution, it has the following advantages and positive effects compared with the prior art: 1. Ultra-low temperature short-time curing significantly reduces energy consumption and improves production efficiency: This invention uses a latent isocyanate curing agent with a desealing temperature of less than or equal to 80°C, and combines it with a specific ratio of medium-to-low boiling range mixed solvents. The slurry of this invention can be cured at 80°C within 10 minutes. Compared with the curing conditions of 120-150°C and more than 30 minutes in the prior art, this invention significantly reduces the curing temperature and time, thereby reducing the risk of thermal damage to heat-sensitive substrates such as PET and ITO, reducing the probability of substrate warping, and significantly reducing production energy consumption and improving production efficiency.

[0022] 2. Excellent screen printing stability, suitable for continuous industrial production. This invention combines low-boiling-point, medium-boiling-point, and high-boiling-point solvents in a mass ratio of (3.5-4.5):(2.5-3.5):(1.5-2.5) to form a medium-to-low boiling-range mixed solvent system. This solvent system can effectively suppress excessively rapid solvent evaporation and viscosity increase during long-term printing, avoiding screen clogging problems. This results in the paste of this invention exhibiting excellent screen printing stability, making it suitable for large-scale continuous production.

[0023] 3. This invention employs a compound of sheet-like, spherical, and nano-silver powders, combined with a suitable resin and curing agent system, resulting in a low volume resistivity after curing the slurry at below 100°C for 10 minutes. This low resistivity facilitates the formation of a highly efficient conductive network, ensuring a rapid response of the smart dimming film upon electrical signal triggering and improving dimming performance. Furthermore, the slurry of this invention exhibits excellent adhesion on various substrates such as PET, ITO glass, PI, and PVDF, achieving a 5B grade in cross-cut adhesion testing. Even after water bath treatment, double 85°C damp heat (500 hours), and thermal shock, the adhesion remains at 5B. This superior adhesion ensures higher reliability in applications requiring long-term stable use, such as architectural glass and automotive windows.

[0024] Because it uses a latent isocyanate curing agent that unblocks at 80°C or less, a dense interpenetrating network structure is formed after curing, which can effectively resist harsh aging tests such as damp heat and thermal shock. After curing, the resistivity of the slurry changes by only 2.1% after 500 hours of dual 85°C damp heat and only 0.8% after thermal shock. This indicates that the resistivity change rate of the slurry of this invention is extremely small during long-term use, which can ensure the long-term stability and uniform color-changing performance of the dimming film in complex environments. Attached Figure Description

[0025] Figure 1 The photos show the samples of the slurry after curing in Example 1 and Comparative Example 6 of this invention after being subjected to an 85°C water bath test for 100 hours, as well as a double 85°C test and a -40°C to -40°C thermal cycling test. Figure 2 The images show the samples of Example 1 and Comparative Example 6 after the slurry was cured and subjected to a water bath test at 85°C for 100 hours, followed by a cross-cut test. Detailed Implementation

[0026] The following detailed description, in conjunction with the accompanying drawings and specific embodiments, provides a low-temperature rapid curing slurry for intelligent dimming electrodes and its preparation method, based on the present invention. The advantages and features of the present invention will become clearer from the following description.

[0027] The flake silver powder D50 used in the following examples and comparative examples has a particle size of 3.0-5.0 μm, the spherical silver powder D50 has a particle size of 0.3-1.0 μm, and the average particle size of the nano silver powder is < 0.1 μm.

[0028] Example 1

[0029] A low-temperature rapid curing slurry for smart dimming electrodes, comprising, by weight percentage: 52 wt% flake silver powder, 13 wt% spherical silver powder, 5 wt% nano silver powder, 15 wt% saturated polyester resin, 3.0 wt% latent isocyanate curing agent, 3 wt% additives, 4 wt% divalent ester, 3 wt% propylene glycol methyl ether acetate, and 2 wt% dimethyl carbonate.

[0030] Example 2

[0031] A low-temperature rapid curing slurry for smart dimming electrodes, comprising, by weight percentage: 46 wt% flake silver powder, 11.5 wt% spherical silver powder, 4.4 wt% nano silver powder, 21.6 wt% saturated polyester resin, 4.4 wt% latent isocyanate curing agent, 3 wt% additives, 4 wt% divalent ester, 3 wt% propylene glycol methyl ether acetate, and 2 wt% dimethyl carbonate.

[0032] Example 3

[0033] A low-temperature rapid curing slurry for smart dimming electrodes, comprising, by weight percentage: 59.4 wt% flake silver powder, 14.85 wt% spherical silver powder, 5.7 wt% nano silver powder, 6.7 wt% saturated polyester resin, 1.35 wt% latent isocyanate curing agent, 3 wt% additives, 4 wt% divalent ester, 3 wt% propylene glycol methyl ether acetate, and 2 wt% dimethyl carbonate.

[0034] Example 4

[0035] A low-temperature rapid curing slurry for smart dimming electrodes, comprising, by weight percentage: 52 wt% flake silver powder, 13 wt% spherical silver powder, 5 wt% nano silver powder, 12 wt% saturated polyester resin, 6.0 wt% latent isocyanate curing agent, 3 wt% additives, 4 wt% divalent ester, 3 wt% propylene glycol methyl ether acetate, and 2 wt% dimethyl carbonate.

[0036] Example 5

[0037] A low-temperature rapid curing slurry for smart dimming electrodes, comprising, by weight percentage: 52 wt% flake silver powder, 13 wt% spherical silver powder, 5 wt% nano silver powder, 16 wt% saturated polyester resin, 2.0 wt% latent isocyanate curing agent, 3 wt% additives, 4 wt% divalent ester, 3 wt% propylene glycol methyl ether acetate, and 2 wt% dimethyl carbonate.

[0038] Comparative Example 1 A low-temperature rapid curing paste for smart dimming electrodes, comprising, by weight percentage: 52 wt% flake silver powder, 13 wt% spherical silver powder, 5 wt% nano silver powder, 15 wt% saturated polyester resin, 3.0% latent isocyanate curing agent, 3 wt% additives, and 9 wt% divalent ester.

[0039] Comparative Example 2 A low-temperature rapid curing slurry for smart dimming electrodes, comprising, by weight percentage: 52 wt% flake silver powder, 13 wt% spherical silver powder, 5 wt% nano silver powder, 15 wt% saturated polyester resin, 3.0% latent isocyanate curing agent, 3 wt% additives, and 9 wt% malondimethyl ether acetate.

[0040] Comparative Example 3 A low-temperature rapid curing slurry for smart dimming electrodes, comprising, by weight percentage: 52 wt% flake silver powder, 13 wt% spherical silver powder, 5 wt% nano silver powder, 15 wt% saturated polyester resin, 3.0% latent isocyanate curing agent, 3 wt% additives, 1 wt% divalent ester, 4 wt% propylene glycol methyl ether acetate, and 4 wt% dimethyl carbonate.

[0041] Comparative Example 4 A low-temperature rapid curing slurry for smart dimming electrodes, comprising, by weight percentage: 52 wt% flake silver powder, 13 wt% spherical silver powder, 5 wt% nano silver powder, 16 wt% saturated polyester resin, 2.0% isocyanate curing agent with an unsealing temperature of 100°C, 3 wt% additives, 4 wt% divalent ester, 3% propylene glycol methyl ether acetate, and 2% dimethyl carbonate.

[0042] Comparative Example 5 A low-temperature rapid curing slurry for smart dimming electrodes, comprising, by weight percentage: 52 wt% flake silver powder, 13 wt% spherical silver powder, 5 wt% nano silver powder, 15 wt% saturated polyester resin, 3.0% latent isocyanate curing agent, 3 wt% additives, 4% isobutyl formate, 4% propyl propionate, and 1% isoamyl butyrate.

[0043] The preparation methods of the slurries in Examples 1-5 and Comparative Examples 1-5 above include the following steps: First, pour all the resin, additives, solvents, and curing agents into the reactor, control the circulating water temperature at 25°C, and stir at 120 r / min for 20 minutes.

[0044] Then, nano silver powder, flake silver powder, and spherical silver powder are added in sequence. The temperature is controlled at 25℃, the stirring speed is 60r / min, and the mixture is stirred for 120 minutes to obtain the slurry.

[0045] Then, the material is ground using a three-roll mill. During the grinding process, the roller gap is gradually reduced, from 120μm to 5μm. Finally, the ground slurry is filtered through a 325-mesh sieve to obtain a uniformly dispersed conductive silver paste with a viscosity of 20-80 Pa·s.

[0046] The formulations of Examples 1-5 and Comparative Examples 1-5 are shown in Table 1:

[0047] Comparative Example 6 Low-temperature silver paste containing 70wt% Ag that is cured at ultra-low temperatures is available on the market.

[0048] Test sample preparation: The examples and comparative examples were screen printed using a Maxwell automatic printing machine at a printing ink return speed of 100 / 100mm / s. Samples were taken at fixed times of 1, 3, and 8 hours during the printing process to compare the viscosity before and after printing.

[0049] The viscosity results of the conductive pastes from Examples 1-3 and Comparative Examples 1-3 and Comparative Example 5 are shown in Table 2 below:

[0050] As shown in Table 2 above, compared with the comparative example, under the resin type and solvent combination selected in Example 1 of this invention, the viscosity of the slurry remained basically unchanged after 1 hour and 3 hours of printing, and only increased slightly after 8 hours of printing. In contrast, Comparative Example 5 showed an increase in viscosity after 1 hour of printing, and the viscosity increased by 700% after 8 hours of printing.

[0051] Examples 2 and 3 are based on Example 1, with the total silver content of the paste adjusted, but the total proportion of solvents remains unchanged. Therefore, the viscosity of the paste changes slightly after 1 hour and 3 hours, but the viscosity remains unchanged after 8 hours of printing.

[0052] Comparative Example 1 was modified from Example 1 to use only divalent ester DBE, which is a high-boiling-point solvent, and the viscosity remained unchanged after long-term printing. Comparative Example 2 used only propylene glycol methyl ether acetate, which has a low boiling point, and therefore the viscosity increased significantly after printing. Compared with Example 1, Comparative Example 3 adjusted the proportions of the three solvents, increasing the total amount of propylene glycol methyl ether acetate and dimethyl carbonate, and decreasing the total amount of dimethyl ester, resulting in a decrease in the overall boiling range and an increase in viscosity after printing.

[0053] Therefore, comparing the above data, it is clear that the selection of specific solvents and the adjustment of their proportions to control the boiling range and polarity are essential to effectively achieve printing stability in this invention.

[0054] Resistivity test sample preparation: The silver paste of the examples and comparative examples was printed and fixed into patterns, and cured in a hot air oven at 80°C for 10 min and 80°C for 30 min. The resistance, film thickness, width and length were tested, the resistivity was calculated, and the resistance of the silver paste formulation was evaluated.

[0055] The resistivity test results are shown in Table 3:

[0056] As can be seen from the data in Table 3, the silver content of Example 2 decreased and the resistance increased compared to Example 1, while the silver content of Example 3 increased and the resistance decreased compared to Example 1. Under the condition that the solvent ratio, resin and curing agent ratio are relatively fixed, the resistance difference between 80℃ for 10 min and 30 min is not significant, and the degree of reaction does not increase when the curing time is extended. In Examples 4 and 5, based on the adjustment of the isocyanate ratio for low-temperature unsealing in Example 1, Example 4 increases the proportion of curing agent, which easily leads to insufficient reaction within 10 minutes, leaving residual small molecules in the system, thus increasing the resistance. Extending the curing time slightly reduces the resistance, but it does not decrease to the resistance level of Example 1. In Example 5, reducing the proportion of curing agent results in an insufficiently dense cross-linked network, leading to an increase in resistance. Even with extended curing time, the resistance does not decrease further because there is no reactive monomer curing agent.

[0057] In Comparative Examples 1, 2, and 3, the solvent ratios were adjusted to affect the boiling range. Comparative Example 1 used all high-boiling-point solvents, thus affecting the reaction extent and resulting in higher resistance at 10 minutes; increasing the time decreased the resistance. Comparative Example 2, using all medium-boiling-point solvents, had a smaller impact on resistance. Comparative Example 3 adjusted the ratios of the three solvents compared to Example 1, increasing the total amount of propylene glycol methyl ether acetate (medium-boiling point) and dimethyl carbonate (low-boiling point) while decreasing the total amount of divalent esters (high-boiling point), resulting in a lower overall boiling range. Therefore, it did not affect the resistance at 10 minutes of curing time.

[0058] In Comparative Example 4, a conventional isocyanate curing agent with a desealing temperature of 100°C was used. The curing agent could not be rapidly and completely desealed and cured at 80°C, resulting in a high overall resistance.

[0059] In Comparative Example 5, the solvent system was changed, using a mixture of 4% isobutyl formate, 4% propyl propionate, and 1% isoamyl butyrate. This solvent combination had a relatively low overall boiling range, resulting in a high initial resistance under 80°C curing conditions. Extending the curing time did not significantly improve the resistance. Different solvent types significantly affect the overlap and spatial arrangement of conductive powders in the formulation. The higher porosity after solvent evaporation caused the resistance of this comparative example to increase by approximately four times compared to Example 1, affecting the color-changing rate of the dimming film in practical applications.

[0060] The 70% Ag low-temperature rapid curing slurry (Comparative Example 6) purchased on the market cannot be cured at 80℃ for 10 minutes, and its resistance is also relatively high after curing for 30 minutes.

[0061] Therefore, as can be seen from the adhesion test and conductivity resistance test, it is necessary to select specific solvents and their proportions, as well as to cooperate with low-temperature unsealing curing agents, in order to achieve stable screen printing, rapid low-temperature curing, and low conductivity after curing.

[0062] The slurry from Example 1 and Comparative Example 6 were screen-printed onto PDLC substrates using the same printing parameters and cured at 80°C for 10 minutes in a hot air oven. The resulting experimental samples were Sample A from Example 1 and Sample B from Comparative Example 6. Samples A and B were subjected to an 85°C water bath test for 100 hours, a double 85 test (a reliability test at 85°C and 85% RH for 500 hours), and a -40°C to -40°C thermal cycling test. The test results are as follows. Figure 1 As shown.

[0063] Samples A-1 and B-1, which underwent a 100-hour water bath test at 85℃, were then subjected to a cross-cut adhesion test. The results are shown in the figure. Figure 2 As shown, the resistance of samples A-2 and B-2 after dual 85 aging and A-3 and B-3 after thermal cycling were tested, and the resistance decay was calculated.

[0064] The results are shown in Table 4:

[0065] Compared with Comparative Example 6, Example 1 showed a resistance increase of less than 3% after undergoing double 85, 500h and thermal shock, which was relatively small. However, Comparative Example 6 showed a significant increase in resistance after aging, which could lead to slow or uneven color change of the dimming film in actual use, affecting product use.

[0066] This demonstrates that the slurry of the present invention has good adhesion, high reliability, and resistance to long-term water bath and damp heat and thermal shock tests.

[0067] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited to the above embodiments. Even if various changes are made to the present invention, if these changes fall within the scope of the claims of the present invention and their equivalents, they shall still fall within the protection scope of the present invention.

Claims

1. A low temperature fast curing paste for smart dimming electrodes, characterized in that, By weight percentage: 30-60% flake silver powder, 10-30% spherical silver powder, 1-10% nano silver powder, 6-22% organic resin, 1-6% curing agent, 0.2-3% additives, and 0.1-10% solvent; The solvent is a medium-to-low boiling range mixed solvent formed by mixing a low-boiling-point solvent, a medium-boiling-point solvent, and a high-boiling-point solvent, wherein the mass ratio of the high-boiling-point solvent, the medium-boiling-point solvent, and the low-boiling-point solvent is (3.5-4.5):(2.5-3.5):(1.5-2.5); The curing agent is a latent isocyanate curing agent with a desealing temperature of less than or equal to 80°C. The low-boiling-point solvent refers to a solvent with a normal boiling point of 80°C to 130°C. The medium-boiling-point solvent refers to a solvent with a normal boiling point of 130°C to 180°C. The high-boiling-point solvent refers to a solvent with a normal boiling point of 180°C to 250°C.

2. The low temperature fast curing paste for smart tintable electrode according to claim 1, wherein, The mass ratio of the high-boiling-point solvent, the medium-boiling-point solvent, and the low-boiling-point solvent is 4:3:

2.

3. The low temperature fast curing paste for smart tintable electrode according to claim 2, wherein, The low-boiling-point solvent is selected from: dimethyl carbonate and / or butyl acetate; the medium-boiling-point solvent is selected from: amyl acetate and / or propylene glycol methyl ether acetate; the high-boiling-point solvent is selected from: any one or a mixture of several of diethylene glycol butyl ether, diethylene glycol ethyl ether, divalent ester, diethylene glycol butyl ether acetate or isophorone.

4. The low temperature fast curing paste for smart tintable electrode according to claim 1, wherein, The latent isocyanate curing agent is any one or a mixture of several of toluene diisocyanate, hexamethylene diisocyanate, or polydiphenylmethane diisocyanate.

5. The low temperature fast curing paste for smart tintable electrode according to claim 1, wherein, By weight percentage, it includes: 46-60% flake silver powder, 11-15% spherical silver powder, 4-6% nano silver powder, 6.7-22% organic resin, 1.3-4.4% curing agent, 3% additives, and 9% organic solvent.

6. The low temperature fast curing paste for smart tintable electrode according to claim 1 or 5, wherein, The flake-shaped silver powder has a D50 particle size of 3.0-5.0 μm and a D100 ≤ 11 μm; the spherical silver powder has a D50 particle size range of 0.3-1.0 μm and a D100 ≤ 3 μm; and the nano-silver powder has an average particle size of < 0.1 μm.

7. The low-temperature rapid curing slurry for intelligent dimming electrodes according to claim 1, characterized in that, The organic resin is selected from one or a mixture of several of the following: modified epoxy resin, acrylic resin, polyurethane resin, or modified polyester resin derivatives.

8. The low temperature fast curing paste for smart tintable electrode according to claim 1, wherein, The additives include any one or more of thixotropic agents, leveling agents, dispersants, and coupling agents; The thixotropic agent is selected from one or more of fumed silica, organobentonite, hydrogenated castor oil, polyamide wax, polyurea, or organic urea. The leveling agent is selected from one or more of acrylic and modified polysiloxane types; The dispersant is selected from one or more of sulfonates, ammonium salts, carboxylates, and polyphosphates; The preferred silane coupling agent is one or more of aminosilane coupling agents, epoxy-terminated silane coupling agents, titanate coupling agents, or aluminate coupling agents.

9. A method for the preparation of a low temperature fast curing paste for smart tinting electrodes, characterized in that, Includes the following steps: According to the formula, the organic resin, additives and solvent are stirred and mixed in the reactor, and the temperature is controlled at 20-35℃. Then, nano silver powder, flake silver powder and spherical silver powder are added in sequence and stirred for 100-120 minutes to obtain a uniform coarse slurry. Then, the coarse slurry is ground with a three-roll mill to obtain a uniformly dispersed finished slurry.

10. The method for preparing the low-temperature rapid curing slurry for intelligent dimming electrodes according to claim 9, characterized in that, The grinding process adopts the way of gradually reducing the roll gap, and the roll gap is adjusted to 120 μm-5 μm successively. The grinding process adopts the way of gradually reducing the roll gap, and the roll gap is adjusted to 120 μm-5 μm successively.

Images