Conductive silver paste, chip polymer laminated aluminum capacitor and preparation method thereof

Abstract

To overcome the problems of high curing temperature and high impedance in existing conductive silver pastes, this invention provides a conductive silver paste comprising silver powder, a solvent, and a low-temperature curing organic resin. The low-temperature curing organic resin is obtained by polycondensation of component A and component B: component A comprises trialkoxysilane units, dialkoxysilane units, and functional siloxane units; the functional siloxane units are selected from siloxane units containing one or more of γ-glycidoxypropyl and γ-methacryloyloxypropyl groups; component B comprises hydroxyl acrylic resin, wherein the molecular weight of the hydroxyl acrylic resin is greater than 1000, and the hydroxyl content is 0.3-0.6 wt%. This invention also discloses a capacitor prepared from the above conductive silver paste and a method for preparing the above conductive silver paste. The conductive silver paste provided by this invention has the characteristic of low-temperature curing, with a curing temperature below 200°C, which can reduce energy consumption in the production process, and exhibits low impedance after curing.

Description

Technical Field

[0001] This invention belongs to the field of capacitor technology, specifically relating to a conductive silver paste, a chip polymer multilayer aluminum capacitor, and a method for preparing the same. Background Technology

[0002] Conductive silver paste possesses excellent conductivity, high-temperature resistance, ease of processing, and stable performance, making it irreplaceable in commercial applications such as fast-moving consumer electronics, solar cells, and multilayer capacitors. For a high-performance conductive paste, the structure, properties, and ratio of the resin binder and silver powder in the formulation regulate the curing temperature, rheology, adhesion, film-forming properties, and stability of the conductive silver paste, influencing the construction of conductive channels during the curing process. Furthermore, this determines the electrical performance of capacitors using conductive silver paste, such as leakage current, series resistance, and reflow soldering properties.

[0003] Polyacrylic acid resin, through its curing temperature, bending properties, viscosity, and printability, can effectively bind conductive silver powder, facilitating the construction of conductive channels, and has been proven to be a curing agent for high-performance conductive pastes. As the structural framework of conductive silver paste, polyacrylic acid resin plays a crucial role in the stable dispersion, curing characteristics, and construction of conductive channels of the conductive phase silver powder in the paste. Silver powder in conductive silver paste is the functional material that enables electron transport; its morphology and proportion in the paste affect the stability and processing characteristics of the paste, ultimately determining the electrical performance of devices using conductive silver paste.

[0004] Existing conductive silver pastes require high-temperature curing, which results in high production energy consumption. Furthermore, the high-temperature curing process has a certain adverse effect on other structures in electronic energy storage components, such as electrolyte performance. In addition, the existing conductive silver pastes have insufficient adhesion to other structures, affecting the fabrication yield of electronic energy storage devices and leading to increased contact impedance, making it difficult to meet the conductivity requirements of some electronic energy storage components. Summary of the Invention

[0005] To address the problems of high curing temperature and high impedance in existing conductive silver pastes, this invention provides a conductive silver paste, a chip polymer multilayer aluminum capacitor, and a method for preparing the same.

[0006] The technical solution adopted by the present invention to solve the above-mentioned technical problems is as follows:

[0007] On one hand, the present invention provides a conductive silver paste, comprising silver powder, solvent and low-temperature curing organic resin;

[0008] The low-temperature curing organic resin is obtained by polycondensation of component A and component B:

[0009] Component A: includes a trialkoxysilane unit, a dialkoxysilane unit, and a functional siloxane unit; the functional siloxane unit is selected from one or more siloxane units containing γ-glycidoxypropyl and γ-methacryloyloxypropyl.

[0010] Component B: includes hydroxyl acrylic resin, wherein the molecular weight of the hydroxyl acrylic resin is greater than 1000 and the hydroxyl content is 0.3-0.6 wt%.

[0011] Optionally, the mass ratio of component A to component B is 5-35:65-95.

[0012] Optionally, in component A, the molar percentage of the trialkoxysilane unit is 25% to 45%, the molar percentage of the dialkoxysilane unit is 50% to 70%, and the molar percentage of the functional siloxane unit is 5% to 15%.

[0013] Optionally, component A has the following structural formula:

[0014] (R1SiO 3 / 2 ) a (R2R3SiO 2 / 2 ) b (R4SiO 3 / 2 ) d (R5R6SiO 2 / 2 ) e

[0015] Where, 0.3≤a≤0.5, 0.5≤b≤0.7, 0<d+e≤0.2, a+b+d+e=1;

[0016] R1, R2, and R3 are each independently selected from one or more of methyl, phenyl, and C2-C13 fluoroalkyl groups; R4 is selected from one or more of γ-glycidoxypropyl and γ-methacryloyloxypropyl; R5 and R6 are each independently selected from one or more of methyl, phenyl, C2-C13 fluoroalkyl groups, γ-glycidoxypropyl, and γ-methacryloyloxypropyl groups, and at least one of R5 and R6 is selected from one or more of γ-glycidoxypropyl and γ-methacryloyloxypropyl groups.

[0017] Optionally, the conductive silver paste comprises the following components by weight:

[0018] 30-60 parts of flake silver powder, 2-15 parts of low-temperature curing organic resin, and 15-50 parts of solvent.

[0019] Optionally, the conductive silver paste further includes 0.1 to 20 parts of spherical silver powder, wherein the particle size of the flake silver powder ranges from 1 to 10 μm, and the particle size of the spherical silver powder ranges from 0.5 to 3 μm.

[0020] Optionally, the solvent includes 10-30 parts of a first solvent and 5-20 parts of a second solvent, wherein the boiling point of the first solvent is less than 200°C and the boiling point of the second solvent is between 200-300°C.

[0021] On the other hand, the present invention provides a chip polymer multilayer aluminum capacitor, including a capacitor core, the capacitor core including a plurality of capacitor chips, the outer layer of the capacitor chips being a conductive silver layer, the plurality of capacitor chips being interconnected by the conductive silver layer, the conductive silver layer being obtained by curing the conductive silver paste as described above.

[0022] On the other hand, the present invention provides a method for preparing the conductive silver paste as described above, comprising the following steps:

[0023] The silane containing one or more of γ-glycidoxypropyl and γ-methacryloyloxypropyl groups is mixed with a hydroxyl acrylic resin and homogeneous.

[0024] By adding an acid catalyst and a reaction solvent, low-temperature curing organic resin is obtained through polycondensation.

[0025] Conductive silver paste is obtained by mixing low-temperature curing organic resin, silver powder and solvent.

[0026] Optionally, the trialkoxysilane is selected from one or more of phenyltrimethoxysilane, methyltrimethoxysilane, and trifluoropropyltrimethoxysilane;

[0027] The dialkoxysilane is selected from one or more of methylphenyldimethoxysilane, diphenyldimethoxysilane, methylphenyldiethoxysilane, diphenyldiethoxysilane, dimethyldimethoxysilane, and dimethyldiethoxysilane;

[0028] The silane containing one or more of γ-glycidoxypropyl and γ-methacryloxypropyl is selected from one or more of γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, and methacryloxypropyltriethoxysilane.

[0029] The conductive silver paste provided by the present invention uses a low-temperature curing organic resin as a resin binder in the conductive silver paste. At the same time, the low-temperature curing organic resin has been improved. The low-temperature curing organic resin obtained by hydrolyzing and condensing a siloxane unit with a hydroxyl acrylic resin using a trialkoxysilane unit, a dialkoxysilane unit, or a siloxane unit containing one or more of γ-glycidoxypropyl and γ-methacryloyloxypropyl groups has the characteristic of low-temperature curing. Its curing temperature is below 200°C, which can reduce the energy consumption of the production process and simplify the preparation process. More importantly, the low-temperature curing organic resin has strong adhesion and low impedance after curing. When applied to chip polymer multilayer aluminum capacitors, it can improve the connection tightness between different capacitor chips, thereby reducing the equivalent series resistance and leakage current of the capacitor and improving the preparation yield of chip polymer multilayer aluminum capacitors. Detailed Implementation

[0030] To make the technical problems solved, the technical solutions, and the beneficial effects of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0031] One embodiment of the present invention provides a conductive silver paste, comprising silver powder, solvent and low-temperature curing organic resin;

[0032] The low-temperature curing organic resin is obtained by polycondensation of component A and component B:

[0033] Component A: includes a trialkoxysilane unit, a dialkoxysilane unit, and a functional siloxane unit; the functional siloxane unit is selected from one or more siloxane units containing γ-glycidoxypropyl and γ-methacryloyloxypropyl.

[0034] Component B: includes hydroxyl acrylic resin, wherein the molecular weight of the hydroxyl acrylic resin is greater than 1000 and the hydroxyl content is 0.3-0.6 wt%.

[0035] The conductive silver paste uses a low-temperature curing organic resin as a resin binder. Furthermore, the low-temperature curing organic resin has been improved. The low-temperature curing organic resin obtained by hydrolyzing and condensing a siloxane unit with hydroxyl acrylic resin using a trialkoxysilane unit, a dialkoxysilane unit, or one or more siloxane units containing γ-glycidoxypropyl or γ-methacryloyloxypropyl groups has the characteristic of low-temperature curing, with a curing temperature below 200°C. This reduces energy consumption in the production process and simplifies the preparation steps. More importantly, this low-temperature curing organic resin exhibits strong adhesion and low impedance after curing. When applied to chip polymer multilayer aluminum capacitors, it can improve the connection tightness between different capacitor chips, thereby reducing the equivalent series resistance and leakage current of the capacitor and improving the yield of chip polymer multilayer aluminum capacitors.

[0036] In some embodiments, the molecular weight of the hydroxyl acrylic resin is greater than 1,000 and less than 1,000,000.

[0037] In some embodiments, the mass ratio of component A to component B is 5–35:65–95.

[0038] When the mass ratio of component A to component B is within the above-mentioned preferred range, the effects of component A and component B can be effectively synergistic, which helps to reduce the equivalent series resistance and leakage current of the chip polymer multilayer aluminum capacitor and improve the preparation yield.

[0039] In some embodiments, in component A, the molar percentage of the trialkoxysilane unit is 25% to 45%, the molar percentage of the dialkoxysilane unit is 50% to 70%, and the molar percentage of the functional siloxane unit is 5% to 15%.

[0040] In a preferred embodiment, in component A, the molar percentage of the trialkoxysilane unit is 30% to 40%, the molar percentage of the dialkoxysilane unit is 60% to 70%, and the molar percentage of the functional siloxane unit is 10% to 15%.

[0041] In some embodiments, component A has the following structural formula:

[0042] (R1SiO 3 / 2 ) a (R2R3SiO 2 / 2 ) b (R4SiO 3 / 2 ) d (R5R6SiO 2 / 2 ) e

[0043] Where, 0.3≤a≤0.5, 0.5≤b≤0.7, 0<d+e≤0.2, a+b+d+e=1;

[0044] R1, R2, and R3 are each independently selected from one or more of methyl, phenyl, and C2-C13 fluoroalkyl groups; R4 is selected from one or more of γ-glycidoxypropyl and γ-methacryloyloxypropyl; R5 and R6 are each independently selected from one or more of methyl, phenyl, C2-C13 fluoroalkyl groups, γ-glycidoxypropyl, and γ-methacryloyloxypropyl groups, and at least one of R5 and R6 is selected from one or more of γ-glycidoxypropyl and γ-methacryloyloxypropyl groups.

[0045] In some embodiments, the C2-C13 fluoroalkyl group is selected from trifluoropropyl, perfluorooctyl, and perfluorodecyl.

[0046] In some embodiments, the conductive silver paste comprises the following components by weight:

[0047] 30-60 parts of flake silver powder, 2-15 parts of low-temperature curing organic resin, and 15-50 parts of solvent.

[0048] In some embodiments, the conductive silver paste further includes 0.5 to 5 parts of an additive.

[0049] The additives include one or more of leveling agents, wetting agents, and defoamers.

[0050] In some embodiments, the solvent includes one or more of ethyl acetate, butyl acetate, diethylene glycol butyl ether acetate, ethylene glycol butyl ether acetate, and propylene glycol methyl ether acetate.

[0051] In some embodiments, the conductive silver paste further includes 0 to 10 parts by weight of aluminum powder or carbon powder.

[0052] In some embodiments, the conductive silver paste further includes 0.1 to 20 parts of spherical silver powder, wherein the particle size of the flake silver powder ranges from 1 to 10 μm, and the particle size of the spherical silver powder ranges from 0.5 to 3 μm.

[0053] By adding an appropriate amount of spherical silver powder to the flake silver powder, the viscosity of the conductive silver paste can be reduced to a certain extent and the amount of silver powder can be increased, which is beneficial to practical operation and improves electrical performance. However, the spherical silver powder should not be added in excess, as excessive addition of spherical silver powder will cause the resistance of the conductive silver paste to increase, which is not conducive to its application in capacitors.

[0054] In a preferred embodiment, the particle size range of the flake-shaped silver powder is 2-5 μm, and the particle size range of the spherical silver powder is 0.5-2 μm.

[0055] In some embodiments, the solvent comprises 10-30 parts of a first solvent and 5-20 parts of a second solvent, wherein the boiling point of the first solvent is less than 200°C and the boiling point of the second solvent is between 200-300°C.

[0056] The conductive silver paste uses a mixture of a low-boiling-point first solvent and a high-boiling-point second solvent. The combination of high and low boiling points can form a solvent evaporation gradient, which helps to reduce the viscosity of the conductive silver paste, improve operability, extend the working time, and increase the drying rate.

[0057] In a preferred embodiment, the first solvent and the second solvent are each independently selected from one or more of esters, ethers and ketones.

[0058] In a more preferred embodiment, the first solvent is selected from one or a mixture of several of butyl acetate, ethyl propionate, ethylene glycol butyl ether, etc.

[0059] The second solvent is selected from one or a mixture of several of diethylene glycol monoethyl ether acetate and diethylene glycol monobutyl ether.

[0060] Another embodiment of the present invention provides a chip polymer multilayer aluminum capacitor, including a capacitor core comprising a plurality of capacitor wafers, the outer layer of each capacitor wafer being a conductive silver layer, the plurality of capacitor wafers being interconnected by the conductive silver layer, the conductive silver layer being obtained by curing conductive silver paste as described above.

[0061] On the other hand, the present invention provides a method for preparing the conductive silver paste as described above, comprising the following steps:

[0062] The silane containing one or more of γ-glycidoxypropyl and γ-methacryloyloxypropyl groups is mixed with a hydroxyl acrylic resin and homogeneous.

[0063] By adding an acid catalyst and a reaction solvent, low-temperature curing organic resin is obtained through polycondensation.

[0064] Conductive silver paste is obtained by mixing low-temperature curing organic resin, silver powder and solvent.

[0065] In some embodiments, the trialkoxysilane is selected from one or more of phenyltrimethoxysilane, methyltrimethoxysilane, and trifluoropropyltrimethoxysilane;

[0066] The dialkoxysilane is selected from one or more of methylphenyldimethoxysilane, diphenyldimethoxysilane, methylphenyldiethoxysilane, diphenyldiethoxysilane, dimethyldimethoxysilane, and dimethyldiethoxysilane;

[0067] The silane containing one or more of γ-glycidoxypropyl and γ-methacryloxypropyl is selected from one or more of γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, and methacryloxypropyltriethoxysilane.

[0068] In some embodiments, during the polycondensation reaction, the polycondensation is first carried out at a hydrolysis temperature of 45-65°C for 3-6 hours, and then the temperature is raised to 75-95°C for 4-8 hours.

[0069] In a preferred embodiment, during the polycondensation reaction, the polycondensation is first carried out at a hydrolysis temperature of 60°C for 5 hours, and then the temperature is raised to 85°C for 7 hours.

[0070] In some embodiments, after polycondensation to obtain a low-temperature curing organic resin, the reaction product is washed with water to remove the acid catalyst, and then the organic layer is separated by extraction with an extractant. The organic layer is repeatedly washed with water until it is neutral, and the extractant is removed by vacuum distillation to obtain the low-temperature curing organic resin.

[0071] In some embodiments, the extractant is selected from at least one of ethyl acetate, methyl acetate, ethyl propionate, toluene, and xylene.

[0072] In some embodiments, the acid catalyst is selected from one or more of hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, trifluoromethanesulfonic acid, acetic acid, oxalic acid, p-toluenesulfonic acid, and acid clay, and the mass ratio of the acid catalyst to the reaction solvent is 0.5:99.5-5:95.

[0073] In some embodiments, the reaction solvent is water or other polar solvents.

[0074] In some embodiments, in component A, the trimekoxysilane accounts for 30% to 50% of the total monomers in molar proportion.

[0075] In a preferred embodiment, the trimekoxysilane in component A accounts for 30% to 40% of the total monomers in molar proportion.

[0076] In some embodiments, in component A, the dialkoxysilane accounts for 50% to 70% of the total monomers in molar proportion.

[0077] In a preferred embodiment, the dialkoxysilane accounts for 60% to 70% of the total monomers in component A.

[0078] In some embodiments, the molar proportion of the silane containing one or more of γ-glycidoxypropyl and γ-methacryloyloxypropyl in component A is 5% to 15%.

[0079] In a preferred embodiment, the molar proportion of the silane containing one or more of γ-glycidoxypropyl and γ-methacryloyloxypropyl in component A is 10% to 15%.

[0080] The present invention will be further illustrated by the following examples.

[0081] Example 1

[0082] This embodiment illustrates the conductive silver paste and its preparation method disclosed in this invention, including the following operations:

[0083] In a 2L four-necked flask equipped with a thermometer, mechanical stirrer, reflux condenser, and constant-pressure dropping funnel, 50g of phenyltrimethoxysilane, 50g of methylphenyldimethoxysilane, 30g of γ-methacryloyloxypropyltrimethoxysilane, 100g of hydroxyl acrylic resin with a molecular weight of 1050 and a hydroxyl content of 0.5wt%, and 100g of ethanol were added sequentially. The mixture was stirred in an oil bath at 45℃ for 10 minutes. Then, over 20 minutes, a mixture of 2.5g of concentrated sulfuric acid and 64g of deionized water was added dropwise into the reaction flask, controlling the temperature of the solution in the reaction flask to not exceed 65℃ during the addition. After the addition was completed, the system temperature was controlled at 60℃ for 5 hours. After the reaction was completed, the temperature was raised to 90℃ and maintained at this temperature for 6 hours. 400g of butyl acetate was added as an extractant, and the acid catalyst was removed by washing with pure water. The organic layer was separated and repeatedly washed with water until neutral. The low-temperature curing organic resin was obtained by vacuum distillation at 90℃.

[0084] By weight, 40 parts of flake silver powder, 10 parts of spherical silver powder, 5.5 parts of low-temperature curing organic resin, 30 parts of butyl acetate, and 14.5 parts of diethylene glycol monoethyl ether acetate were sequentially added to a planetary dynamic mixing vessel and mixed for 6 hours. The mixture was then filtered to obtain conductive silver paste.

[0085] Example 2

[0086] This embodiment illustrates the conductive silver paste and its preparation method disclosed in this invention, including most of the operations in Example 1, with the following differences:

[0087] By weight, 30 parts of flake silver powder, 20 parts of spherical silver powder, 5.5 parts of low-temperature curing organic resin, 30 parts of butyl acetate, and 14.5 parts of diethylene glycol monoethyl ether acetate were added sequentially to a planetary dynamic mixing vessel and mixed for 6 hours. The mixture was then filtered to obtain conductive silver paste.

[0088] Example 3

[0089] This embodiment illustrates the conductive silver paste and its preparation method disclosed in this invention, including most of the operations in Example 1, with the following differences:

[0090] By weight, 60 parts of flake silver powder, 6.2 parts of low-temperature curing organic resin, 25 parts of butyl acetate, and 8.8 parts of diethylene glycol monoethyl ether acetate were added sequentially to a planetary dynamic mixing vessel and mixed for 6 hours. The mixture was then filtered to obtain conductive silver paste.

[0091] Example 4

[0092] This embodiment illustrates the conductive silver paste and its preparation method disclosed in this invention, including most of the operations in Example 1, with the following differences:

[0093] By weight, 40 parts of flake silver powder, 20 parts of spherical silver powder, 6.5 parts of low-temperature curing organic resin, 25 parts of butyl acetate, and 8.5 parts of diethylene glycol monoethyl ether acetate were added sequentially to a planetary mixing vessel and stirred for 6 hours. The mixture was then filtered to obtain conductive silver paste.

[0094] Example 5

[0095] This embodiment illustrates the conductive silver paste and its preparation method disclosed in this invention, including most of the operations in Example 1, with the following differences:

[0096] By weight, 40 parts of flake silver powder, 20 parts of spherical silver powder, 6.5 parts of low-temperature curing organic resin, and 33.5 parts of butyl acetate were added sequentially to a planetary dynamic mixing vessel and mixed for 6 hours. The mixture was then filtered to obtain conductive silver paste.

[0097] Example 6

[0098] This embodiment illustrates the conductive silver paste and its preparation method disclosed in this invention, including most of the operations in Example 1, with the following differences:

[0099] By weight, 40 parts of flake silver powder, 20 parts of spherical silver powder, 6.5 parts of low-temperature curing organic resin, and 33.5 parts of diethylene glycol monoethyl ether acetate were added sequentially to a planetary dynamic mixing vessel and mixed for 6 hours. The mixture was then filtered to obtain conductive silver paste.

[0100] Example 7

[0101] This embodiment illustrates the conductive silver paste and its preparation method disclosed in this invention, including most of the operations in Example 1, with the following differences:

[0102] γ-glycidoxypropyltrimethoxysilane was used to replace γ-methacryloxypropyltrimethoxysilane in Example 1.

[0103] Comparative Example 1

[0104] This comparative example is used to illustrate the conductive silver paste and its preparation method disclosed in this invention, and includes the following operations:

[0105] By weight, 40 parts of flake silver powder, 20 parts of spherical silver powder, 6.5 parts of hydroxyl acrylic resin with a molecular weight of 1050 and a hydroxyl content of 0.5 wt%, 25 parts of butyl acetate, and 8.5 parts of diethylene glycol monoethyl ether acetate were sequentially added to a planetary dynamic mixing vessel and mixed for 6 hours. The mixture was then filtered to obtain conductive silver paste.

[0106] Performance testing

[0107] The viscosity, sheet resistance and fineness of the conductive silver paste prepared above were tested, and the test results were filled in Table 1.

[0108] The conductive silver paste prepared above was used to prepare a capacitor chip and tested by the following method: 2.5V 330uf aluminum foil with a surface impregnated with conductive polymer and conductive carbon paste was used to impregnate the conductive silver paste. After air drying at room temperature for 0.5h, it was placed at 150℃ for another 0.5h to obtain the capacitor chip. The impedance of the capacitor chip was tested using Zhixin Precision ZX1085-1X, and the test results were filled in Table 1.

[0109] Table 1

[0110]

[0111]

[0112] As can be seen from the test results in Table 1, the conductive silver paste provided by the present invention has lower sheet resistance and viscosity, which is beneficial for the impregnation operation of capacitor wafers and reduces the internal resistance of the prepared capacitor. At the same time, the capacitor wafers prepared using the conductive silver paste provided by the present invention have lower impedance, which can effectively improve the electrochemical performance of the capacitor.

[0113] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A conductive silver paste, characterized in that, Includes silver powder, solvents, and low-temperature curing organic resins; The low-temperature curing organic resin is obtained by polycondensation of component A and component B: Component A: comprises a trialkoxysilane unit, a dialkoxysilane unit, and a functional siloxane unit; the functional siloxane unit is selected from siloxane units containing one or more of γ-glycidoxypropyl and γ-methacryloyloxypropyl groups; in component A, the molar percentage of the trialkoxysilane unit is 25%~45%, the molar percentage of the dialkoxysilane unit is 50%~70%, and the molar percentage of the functional siloxane unit is 5%~15%; Component B: includes hydroxyl acrylic resin, wherein the molecular weight of the hydroxyl acrylic resin is greater than 1000 and the hydroxyl content is 0.3-0.6 wt%.

2. The conductive silver paste according to claim 1, characterized in that, The mass ratio of component A to component B is 5~35:65~95.

3. The conductive silver paste according to claim 1, characterized in that, Component A has the following structural formula: (R1SiO 3 / 2 ) a (R2R3SiO 2 / 2 ) b (R4SiO 3 / 2 ) d (R5R6SiO 2 / 2 ) e Where, 0.3≤a≤0.5, 0.5≤b≤0.7, 0<d+e≤0.2, a+b+d+e=1; R1, R2, and R3 are each independently selected from one or more of methyl, phenyl, and C2-C13 fluoroalkyl groups; R4 is selected from one or more of γ-glycidoxypropyl and γ-methacryloyloxypropyl; R5 and R6 are each independently selected from one or more of methyl, phenyl, C2-C13 fluoroalkyl groups, γ-glycidoxypropyl, and γ-methacryloyloxypropyl groups, and at least one of R5 and R6 is selected from one or more of γ-glycidoxypropyl and γ-methacryloyloxypropyl groups.

4. The conductive silver paste according to claim 1, characterized in that, The conductive silver paste comprises the following components by weight: 30-60 parts of flake silver powder, 2-15 parts of low-temperature curing organic resin, and 15-50 parts of solvent.

5. The conductive silver paste according to claim 4, characterized in that, The conductive silver paste further includes 0.1 to 20 parts of spherical silver powder, wherein the particle size of the flake silver powder ranges from 1 to 10 μm, and the particle size of the spherical silver powder ranges from 0.5 to 3 μm.

6. The conductive silver paste according to claim 4, characterized in that, The solvent comprises 10-30 parts of a first solvent and 5-20 parts of a second solvent, wherein the boiling point of the first solvent is less than 200°C and the boiling point of the second solvent is between 200-300°C.

7. A chip polymer multilayer aluminum capacitor, characterized in that, The device includes a capacitor core, which comprises multiple capacitor wafers. The outer layer of each capacitor wafer is a conductive silver layer. The multiple capacitor wafers are interconnected by the conductive silver layer. The conductive silver layer is obtained by curing the conductive silver paste according to any one of claims 1 to 6.

8. The method for preparing conductive silver paste according to any one of claims 1 to 6, characterized in that, The following steps are included: The silane containing one or more of γ-glycidoxypropyl and γ-methacryloyloxypropyl groups is mixed with a hydroxyl acrylic resin until homogeneous. By adding an acid catalyst and a reaction solvent, low-temperature curing organic resin is obtained through polycondensation. Conductive silver paste is obtained by mixing low-temperature curing organic resin, silver powder and solvent.

9. The method for preparing conductive silver paste according to claim 8, characterized in that, The trialkoxysilane is selected from one or more of phenyltrimethoxysilane, methyltrimethoxysilane, and trifluoropropyltrimethoxysilane; The dialkoxysilane is selected from one or more of methylphenyldimethoxysilane, diphenyldimethoxysilane, methylphenyldiethoxysilane, diphenyldiethoxysilane, dimethyldimethoxysilane, and dimethyldiethoxysilane; The silane containing one or more of γ-glycidoxypropyl and γ-methacryloyloxypropyl is selected from one or more of γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-methacryloyloxypropyltrimethoxysilane, and methacryloyloxypropyltriethoxysilane.

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