High-density antioxidant MLCC copper terminal electrode slurry and preparation method thereof

Abstract

The invention discloses a high-density antioxidant MLCC copper terminal electrode slurry and a preparation method thereof, and relates to the technical field of novel coatings. The invention relates to a high-density antioxidant MLCC (multilayer ceramic capacitor) copper terminal electrode paste, which is composed of the following components in parts by mass: 75.0 to 88.0 parts of conductive copper powder, 3.0 to 8.0 parts of inorganic glass powder, 8.0 to 18.0 parts of organic carrier, 0.5 to 3.0 parts of antioxidant additive, and 0.1 to 1.5 parts of dispersion modifier. The antioxidant additive effectively prevents contact between oxygen and copper, so that conversion of copper powder to copper oxide or cuprous oxide is inhibited from the source, and the problem of oxidation discoloration caused by loss of protection in a high-temperature sintering stage of traditional slurry is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of new coatings, in particular to a high-density oxidation-resistant MLCC copper terminal electrode paste and a preparation method thereof. BACKGROUND

[0002] With the rapid development of electronic information technology, electronic components are evolving towards miniaturization, high frequency, high reliability and low cost. Multilayer ceramic capacitors (MLCC) are indispensable basic passive components in electronic circuits, widely used in consumer electronics, automotive electronics and 5G communication fields. In the manufacturing process of MLCC, the terminal electrode paste plays a crucial role, which is responsible for connecting the internal electrodes in parallel and directly determines the electrical performance and soldering reliability of the capacitor.

[0003] Traditional MLCC terminal electrodes mostly use silver (Ag) or silver-palladium (Ag-Pd) paste, but due to the high price of noble metals and the problem of silver migration, copper (Cu) terminal electrode paste with low cost and excellent anti-electromigration performance has gradually become the mainstream alternative. However, as a base metal, copper has relatively active chemical properties and is prone to oxidation during high-temperature sintering. This characteristic brings great technical challenges to the preparation of copper terminal electrodes: on the one hand, the oxidation of the copper powder surface generates a layer of copper oxide (CuO) or cuprous oxide (Cu2O), which seriously hinders the formation of sintering necks between copper particles, leading to loose electrode layer structure, low density, and thus poor adhesion between the terminal electrode and the ceramic body, which can cause acid penetration during subsequent electroplating and product failure; on the other hand, the presence of the oxidation layer significantly increases the contact resistance and equivalent series resistance (ESR) of the electrode, deteriorating the electrical performance of the MLCC.

[0004] To solve the problem of copper powder oxidation, existing technologies usually use inert atmospheres such as nitrogen for sintering, but this not only increases equipment and process costs, but also cannot completely eliminate the influence of trace amounts of oxygen. Another common method is to add antioxidants or perform surface coating treatment on the copper powder. However, traditional organic antioxidants often have too low thermal decomposition temperatures, and volatilize completely at the initial stage of sintering, failing to provide continuous protection on the copper powder surface during the highest temperature stage. Or their decomposition is incomplete, and the residual carbide hinders the wetting and flow of inorganic glass powder, further affecting the densification of the electrode.

[0005] Therefore, how to develop a copper terminal electrode paste that can effectively adsorb on the surface of copper powder to inhibit oxidation during the sintering temperature rise stage, while promoting the densification of the paste and having no residual side effects, is a key technical problem that needs to be solved in the current MLCC manufacturing field. SUMMARY

[0006] The application aims to solve the problem of oxidation of copper end electrodes in the prior art during sintering, which leads to low density and poor electrical performance, and provides a high-density oxidation-resistant MLCC copper end electrode paste and a preparation method thereof. By introducing a new structure-specific alkyl imidazole derivative as an oxidation-resistant additive, the oxidation of copper powder during sintering is effectively inhibited, the density and conductivity of the electrode layer are significantly improved, and the bonding strength between the electrode layer and the ceramic matrix is enhanced.

[0007] To achieve the above-mentioned object, the technical scheme adopted by the application is: In a first aspect, the application provides an oxidation-resistant additive, which is an alkyl imidazole derivative. The alkyl imidazole derivative is a compound as shown in formula 1. Formula 1 ; In formula 1, R1 is any one of H, an alkyl group with 1-5 carbon atoms, and a phenyl group.

[0008] By adopting the above technical scheme, further, the oxidation-resistant additive is used to adsorb on the surface of copper powder during sintering to inhibit oxidation. The alkyl imidazole derivative is any one of the compounds as shown in the following structures: Alkyl imidazole derivative 1; Alkyl imidazole derivative 2; Alkyl imidazole derivative 3; Alkyl imidazole derivative 4; Alkyl imidazole derivative 5; Alkyl imidazole derivative 6.

[0009] The first aspect of the application provides an alkyl imidazole derivative, which contains an imidazole ring and a long-chain alkyl side chain. The nitrogen atom on the imidazole ring has strong lone pair electron supply capability and forms a chemical bond adsorption layer with the Cu atoms on the surface of copper powder, thereby preferentially covering the copper surface during sintering and heating, blocking the direct contact of oxygen or moisture with copper, and significantly inhibiting the oxidation reaction of Cu→CuO / Cu2O; at the same time, the long-chain alkyl end has hydrophobicity and thermal stability, can maintain the integrity of the adsorption film at high temperature, and reduce oxygen diffusion. In the composite system, the alkyl imidazole derivative has good compatibility with the organic carrier and can be uniformly dispersed in the paste system, and forms a dense and ordered organic protective layer on the surface of the copper powder. The layer gradually pyrolyzes during subsequent heating and sintering, and the decomposition products promote the wetting of the glass phase with the copper powder and the formation of sintering necks, thereby realizing the synergistic effect of oxidation resistance and sintering densification.

[0010] In a second aspect, the application provides a high-density oxidation-resistant MLCC copper terminal electrode paste, which is composed of the following components in parts by mass: conductive copper powder 75.0-88.0 parts, inorganic glass powder 3.0-8.0 parts, organic carrier 8.0-18.0 parts, oxidation-resistant additive 0.5-3.0 parts, and dispersion modifier 0.1-1.5 parts.

[0011] By adopting the above technical solution, further, the conductive copper powder is a mixture of spherical copper powder and flaky copper powder, and the mass ratio of the spherical copper powder to the flaky copper powder is (3-5):1.

[0012] By adopting the above technical solution, further, the average particle size distribution D90-D10 of the spherical copper powder is ≤1.5 μm.

[0013] By adopting the above technical solution, further, the average particle size distribution D90-D10 of the flaky copper powder is ≤2.5 μm.

[0014] By adopting the above technical solution, further, the inorganic glass powder is a lead-free low-temperature melting glass powder with an initial melting temperature of 350-780 ℃.

[0015] By adopting the above technical solution, further, the organic carrier is prepared by dissolving a high molecular resin in an organic solvent, and the organic carrier contains, in parts by mass, high molecular resin 10-25 parts and organic solvent 75-90 parts.

[0016] By adopting the above technical solution, further, the high molecular resin is selected from one or more of ethyl cellulose, acrylic resin, or polyvinyl butyral.

[0017] By adopting the above technical solution, further, the organic solvent is selected from one or more of terpineol, butyl carbitol acetate, diethylene glycol monobutyl ether, or tridecanol.

[0018] By adopting the above technical solution, further, the dispersion modifier is selected from one or more of phosphate ester, oleic acid, stearic acid, polyethylene glycol, polyvinylpyrrolidone, polyester-type high molecular dispersant, or polyurethane-type high molecular dispersant.

[0019] In a third aspect, the application provides a preparation method of a high-density oxidation-resistant MLCC copper terminal electrode paste, which comprises the following steps: S1, organic carrier preparation: adding a high molecular resin into an organic solvent, stirring and dissolving under water bath conditions at 60-90 ℃ until a uniform organic carrier is formed, standing for defoaming, and standby; S2, premixing: the conductive copper powder, inorganic glass powder, antioxidant additive and dispersion modifier are added into the organic carrier in proportion, and a planetary mixer is used for premixing, and the stirring time is 30-60 minutes, to obtain a premixing material; S3, grinding and dispersing: the premixing material is rolled and ground by using a three-roll grinder until the fineness of the slurry reaches a predetermined standard; S4, post-treatment: the ground slurry is vacuum degassed and filtered to obtain the final high-density antioxidant MLCC copper electrode slurry.

[0020] By adopting the above technical scheme, further, in the S2, the antioxidant additive is dispersed in the organic carrier before the conductive copper powder is added, and then the conductive copper powder is added, and then mixed with other components.

[0021] By adopting the above technical scheme, further, the three-roll grinder rolling process in the step S3 is divided into two stages of coarse grinding and fine grinding, the coarse grinding roll gap spacing is set to 20-50 mu m, and the rolling is 1-2 times; the fine grinding roll gap spacing is set to 5-15 mu m, and the rolling is 3-5 times.

[0022] By adopting the above technical scheme, further, in the S4, the filtering is carried out by using a 80-100 mesh stainless steel wire mesh for pressure filtration, the vacuum degree of the vacuum degassing is controlled at-0.08MPa to-0.095MPa, and the time is 10-20 minutes.

[0023] The present application solves the technical problems of easy oxidation, low density and poor adhesion of copper electrode in sintering by the synergistic effect of the specific mass ratio of each component, the cooperation of alkyl imidazole antioxidant additive and conductive copper powder and inorganic glass powder. In the formula system, the alkyl imidazole derivative forms a firm chemical bond adsorption layer with copper atom by using the lone pair electrons of nitrogen atom on imidazole ring, which preferentially covers the copper surface in the key stage of sintering temperature rise, and inhibits the conversion of Cu to CuO / Cu2O from the source by using the hydrophobicity and thermal stability of long-chain alkyl; this protective layer not only prevents oxidation, but also gradually pyrolyzes in the subsequent high-temperature sintering, and the decomposition products can synergistically promote the wetting and flow of inorganic glass powder on copper powder, and accelerate the formation of sintering neck. This synergistic mechanism avoids the problem that the incomplete decomposition of traditional antioxidant additives leaves carbide and hinders the flow of glass, so as to ensure high conductivity, realize high densification of electrode layer and strong adhesion with ceramic matrix.

[0024] Compared with the prior art, the present application has the following advantages: 1.The alkyl imidazole derivative of the present application is used as an antioxidant with a specific structure, which is different from the traditional organic antioxidant in the prior art which is prone to premature volatilization or incomplete decomposition. The derivative forms a firm chemisorption layer with the lone pair electrons of the nitrogen atom of the imidazole ring on the surface of copper powder, and cooperates with the steric effect of the long-chain alkyl group to continuously and stably coat the copper powder in the key stage of sintering temperature rise. This mechanism effectively blocks the contact between oxygen and copper, inhibits the conversion of copper powder to copper oxide or cuprous oxide from the source, and solves the problem of oxidation discoloration caused by the loss of protection of traditional slurry in the high-temperature sintering stage.

[0025] 2.Different from the residual carbide of the antioxidant in the prior art which hinders the flow of glass powder, the antioxidant additive of the present application can synergistically promote the wetting and flow of inorganic glass powder to copper powder after completing its protection mission. This synergistic effect not only avoids the porosity and loose structure caused by carbon residue, but also accelerates the formation of sintering neck, significantly improves the density of the electrode layer and the bonding strength of the end electrode and the ceramic matrix, thereby effectively improving the problems of high contact resistance and acid liquid penetration failure caused by the existence of the oxidation layer.

[0026] 3.By optimizing the grading of spherical copper powder and flaky copper powder and combining with a specific dispersion modifier system, the present application constructs a highly stable dispersion system. Compared with the slurry in the prior art which is prone to agglomeration or sedimentation, the slurry prepared by the present application can maintain the stability of viscosity under long-term natural storage conditions, and no obvious thickening or blackening and metamorphic phenomenon occurs. This ensures that the slurry still has good printing adaptability and consistency of appearance color after long-time storage. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 NMR chart of the alkyl imidazole derivative 1 of the present application. DETAILED DESCRIPTION

[0028] The technical solutions of the present application will be described clearly and completely in combination with the drawings in the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0029] Preparation Example 1 Preparation of the alkyl imidazole derivative 1: ; Put 3 g of compound 1 and 5.30 g of compound 2 into a dry pressure-resistant three-necked flask, add 50 ml of anhydrous N, N-dimethylformamide (DMF) as a solvent for dissolution, and then sequentially add cuprous iodide 0.26 g, 1, 10-phenanthroline 0.5 g, and cesium carbonate 8.8 g; after the reaction system is subjected to three vacuum-nitrogen replacement operations, it is heated to 110°C under a nitrogen atmosphere and stirred for 12 hours, during which the disappearance of the raw material is monitored by TLC; after the reaction is completed, the system is cooled to room temperature, and insoluble inorganic salts are removed by filtration through diatomite; the filtrate is diluted with ethyl acetate and washed with saturated brine three times to remove DMF; the organic phase is dried over anhydrous sodium sulfate, filtered, and the solvent is removed by rotary evaporation under reduced pressure; the obtained crude product is separated and purified by silica gel column chromatography (the mobile phase is eluted with petroleum ether / ethyl acetate gradient, petroleum ether (PE): ethyl acetate (EA) from 20:1 to 8:1); the mobile phase is removed by rotary evaporation under reduced pressure to obtain the target product compound 3, 5.50 g.

[0030] ; Put 5.50 g of compound 3 and 2.1 g of compound 4 into a dry reaction flask, dissolve with 60 mL of anhydrous dimethylacetamide, and sequentially add 115 mg of palladium acetate, 270 mg of triphenylphosphine, and 3.0 g of anhydrous potassium carbonate; the system is heated to 120°C under a nitrogen atmosphere and refluxed for 16 hours under light-proof conditions; after the reaction is completed, the mixture is cooled to room temperature, diluted with 100 mL of ethyl acetate, filtered through a diatomite pad to remove palladium black and inorganic salts, and the filter cake is washed with a small amount of ethyl acetate. The filtrate is transferred to a separatory funnel and washed sequentially with water (3 x 50 mL) and saturated brine (50 mL); the organic phase is dried over anhydrous sodium sulfate, and the solvent is removed by rotary evaporation to obtain a crude product. The crude product is purified by silica gel column chromatography, eluted with petroleum ether: ethyl acetate (10:1 to 5:1) gradient, and the mobile phase is removed by rotary evaporation under reduced pressure to obtain the target product, alkyl imidazole derivative 1, 3.43 g.

[0031] Product structure identification data: Mass spectrum of compound 3 [M+H] + (m+1): 534; Mass spectrum of alkyl imidazole derivative 1 [M+H] + (m+1): 586, see Figure 1 .

[0032] Preparation examples 2-6 In preparation examples 2-6, alkyl imidazole derivatives 2-6 are sequentially prepared according to the preparation method of preparation example 1, with compound 4 replaced, and the rest remaining the same as preparation example 1. See Table 1 for details.

[0033] Table 1 Example 1 Preparation of a high-density antioxidant MLCC copper terminal electrode paste 1. Raw material mass fraction formula: Conductive copper powder: 80.0 parts (spherical copper powder and flaky copper powder mass ratio 4:1; average particle size D50 of spherical copper powder = 1.0 μm, average particle size D50 of flaky copper powder = 4.0 μm); Inorganic glass powder: 5.0 parts (lead-free low-temperature melting glass powder with an initial melting temperature of 550°C); Organic carrier: 12.0 parts (consisting of 15 parts of ethyl cellulose and 85 parts of terpineol); Antioxidant additive: 1.5 parts (alkyl imidazole derivative 1 obtained in Preparation Example 1); Dispersion modifier: 0.8 parts (phosphate ester).

[0034] 2. Preparation method: S1, organic carrier preparation: 15 parts of ethyl cellulose were added to 85 parts of terpineol, and dissolved by stirring in a 75°C water bath environment until a uniform transparent organic carrier was formed. After stopping stirring, it was left to stand for 12 hours to remove bubbles and was ready for use; S2, premixing: 1.5 parts of alkyl imidazole derivative 1 was first added to the above organic carrier and stirred and dispersed for 15 minutes until uniform; then 80.0 parts of conductive copper powder, 5.0 parts of inorganic glass powder and 0.8 parts of phosphate ester were added and put into a planetary mixer for premixing, with a stirring speed of 300 r / min and a stirring time of 45 minutes, to obtain a uniform premix; S3, grinding and dispersion: the premix was sent to a three-roll grinder for rolling and grinding, with two stages of coarse grinding and fine grinding. The roll gap was set to 30 μm for coarse grinding and rolled once; the roll gap was adjusted to 10 μm for fine grinding and rolled four times, until the paste fineness was ≤15 μm; S4, post-treatment: the ground paste was filtered using a 90-mesh stainless steel screen to remove impurity particles; then the filtered paste was placed in a vacuum degassing tank, with a vacuum degree of -0.09 MPa and a degassing time of 15 minutes, to obtain a high-density antioxidant MLCC copper terminal electrode paste.

[0035] Examples 2-6 Preparation of a high-density antioxidant MLCC copper terminal electrode paste, referring to the preparation method of Example 1, the antioxidant additive therein was replaced with antioxidant additive 2-antioxidant additive 6 in turn, and the rest remained the same as in Example 1.

[0036] Comparative Example 1 A high-density antioxidant MLCC copper terminal electrode paste was prepared according to the preparation method of Example 1, wherein the antioxidant additive was replaced by alkyl imidazole (C8H15N2) in turn, and the rest was the same as Example 1.

[0037] Comparative Example 2 A high-density antioxidant MLCC copper terminal electrode paste was prepared according to the preparation method of Example 1, wherein the antioxidant additive was replaced by benzotriazole in turn, and the rest was the same as Example 1.

[0038] Comparative Example 3 A high-density antioxidant MLCC copper terminal electrode paste was prepared according to the preparation method of Example 1, wherein the antioxidant additive was replaced by zinc stearate in turn, and the rest was the same as Example 1.

[0039] Comparative Example 4 A high-density antioxidant MLCC copper terminal electrode paste was prepared according to the preparation method of Example 1, wherein the dispersing modifier was not added, and the rest was the same as Example 1.

[0040] Comparative Example 5 A high-density antioxidant MLCC copper terminal electrode paste was prepared according to the preparation method of Example 1, wherein the mass fraction of the high molecular resin was replaced by 65 parts, and the rest was the same as Example 1.

[0041] Comparative Example 6 A high-density antioxidant MLCC copper terminal electrode paste was prepared according to the preparation method of Example 1, wherein the mass ratio of spherical copper powder to flaky copper powder was replaced by 1:1, and the rest was the same as Example 1.

[0042] Performance test: 1. Sintering discoloration observation: The paste was coated on an alumina ceramic substrate and sintered in an air atmosphere or a low oxygen partial pressure atmosphere. The color change of the electrode surface after sintering was observed. If the surface presents a bright copper red color, it indicates good oxidation resistance; if the surface is black or red, it indicates poor oxidation resistance. The data is shown in Table 2.

[0043] 2. Viscosity test: A rotary viscometer was used to measure the viscosity value of each group of paste under constant temperature condition of 25°C, rotor (CPE-52) and rotation speed (5 rpm) were selected, the data is shown in Table 2.

[0044] 3. Long-term storage stability test: The sample was stored in natural environment for 1 year, and the sintering discoloration was retested, the data is shown in Table 2.

[0045] Table 2 ​Examples 1-6 exhibit excellent "bright copper red" appearance and stable viscosity, the underlying reason is that the special structure of the alkyl imidazole derivatives introduced plays a dual protection mechanism: the nitrogen atom on the imidazole ring forms a firm chemical adsorption layer with the surface of copper powder through lone pair electrons, and the steric effect and hydrophobicity of long chain alkyl effectively block the penetration of oxygen in the key stage of sintering temperature rise, thereby inhibiting the conversion of Cu to CuO / Cu2O. In contrast, Comparative Example 1 (ordinary alkyl imidazole) and Comparative Example 2 (benzotriazole) cannot protect the copper powder at high temperature due to insufficient thermal stability or weak adsorption, resulting in partial oxidation discoloration (red black / blackening); Comparative Example 3 (zinc stearate) may cause severe blackening due to decomposition residues hindering sintering.

[0046] Comparative Example 4 lacks a dispersion modifier, resulting in copper powder agglomeration (a sharp increase in viscosity), so that the antioxidant cannot form a uniform coating on the surface of the copper powder, causing local oxidation "mottling"; in Comparative Example 5, excessive high molecular resin (65 parts) causes the organic carrier to be unable to completely volatilize during sintering, and the residual carbide causes the electrode to present "gray black" and abnormally high viscosity; and in Comparative Example 6, the optimal packing ratio of spherical and flaky copper powder (1:1) is changed, which destroys the dense packing structure and increases the porosity, thereby introducing more oxygen to cause oxidation to be "dark red". In summary, only a specific antioxidant structure combined with an optimized dispersion and carrier system can achieve the synergy of oxidation resistance and high density.

[0047] Although embodiments of the present application have been shown and described, it is to be understood that various modifications, substitutions, replacements and changes can be made to these embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A high-density, oxidation-resistant MLCC copper end electrode paste, characterized in that, By weight, the slurry is composed of the following components: 75.0-88.0 parts conductive copper powder, 3.0-8.0 parts inorganic glass powder, 8.0-18.0 parts organic carrier, 0.5-3.0 parts antioxidant additive, and 0.1-1.5 parts dispersant modifier; The antioxidant additive is an alkylimidazol derivative; The alkylimidazol derivatives have the structure shown in Formula 1; Formula 1 ; In Formula 1, R1 is any one of H, alkyl groups with 1-5 carbon atoms, or phenyl groups.

2. The high-density, oxidation-resistant MLCC copper end electrode paste according to claim 1, characterized in that, The conductive copper powder is a mixture of spherical copper powder and flake copper powder, wherein the mass ratio of spherical copper powder to flake copper powder is (3-5):1; The average particle size distribution of the spherical copper powder is D90-D10≤1.5μm; The average particle size distribution of the flaky copper powder is D90-D10≤2.5μm.

3. The high-density, oxidation-resistant MLCC copper end electrode paste according to claim 1, characterized in that, The inorganic glass powder is a lead-free low-temperature melting glass powder with an initial melting temperature of 350-780℃.

4. The high-density, oxidation-resistant MLCC copper end electrode paste according to claim 1, characterized in that, The organic carrier is made by dissolving a polymer resin in an organic solvent. By mass, the organic carrier comprises: 10-25 parts of polymer resin and 75-90 parts of organic solvent. The polymer resin is selected from one or more of ethyl cellulose, acrylic resin, or polyvinyl butyral. The organic solvent is selected from one or more of terpineol, butyl carbitol acetate, diethylene glycol monobutyl ether, or tridecyl alcohol.

5. The high-density, oxidation-resistant MLCC copper end electrode paste according to claim 1, characterized in that, The dispersing modifier is selected from one or more of the following: phosphate ester, oleic acid, stearic acid, polyethylene glycol, polyvinylpyrrolidone, polyester-type polymeric dispersant, or polyurethane-type polymeric dispersant.

6. The high-density, oxidation-resistant MLCC copper end electrode paste according to claim 1, characterized in that, The antioxidant additive is used to adsorb onto the surface of copper powder during the sintering heating stage to inhibit oxidation; The alkylimidazol derivative is any one of the compounds shown in the following structures: Alkyl imidazole derivatives 1; 2. Alkyl imidazole derivatives; 3. Alkyl imidazole derivatives; 4. Alkyl imidazole derivatives; 5. Alkyl imidazole derivatives; 6. Alkyl imidazole derivatives.

7. A method for preparing a high-density, antioxidant MLCC copper end electrode paste as described in any one of claims 1-6, characterized in that, Includes the following steps: S1. Preparation of organic carrier: Add the polymer resin to the organic solvent and stir to dissolve it under water bath conditions of 60℃-90℃ until a uniform organic carrier is formed. Let it stand to defoam and set aside for later use. S2. Premixing: The conductive copper powder, inorganic glass powder, antioxidant additive and dispersant modifier are added to the organic carrier in proportion, and premixed using a planetary mixer for 30-60 minutes to obtain a premixed material. S3. Grinding and dispersing: The premixed material is rolled and ground using a three-roll mill until the fineness of the slurry reaches the predetermined standard; S4. Post-processing: The ground slurry is subjected to vacuum degassing and filtration to obtain the final high-density, antioxidant MLCC copper end electrode slurry.

8. The method for preparing a high-density, antioxidant MLCC copper end electrode paste according to claim 7, characterized in that, In step S2, before adding the conductive copper powder, the antioxidant additive is first dispersed in the organic carrier, then the conductive copper powder is added, and then it is mixed with other components.

9. The method for preparing a high-density, antioxidant MLCC copper end electrode paste according to claim 7, characterized in that, The three-roll mill rolling process in step S3 is divided into two stages: rough grinding and fine grinding. The rough grinding roll gap is set to 20μm-50μm and rolled 1-2 times; the fine grinding roll gap is set to 5μm-15μm and rolled 3-5 times.

10. The method for preparing a high-density, antioxidant MLCC copper end electrode paste according to claim 7, characterized in that, The filtration in S4 uses an 80-100 mesh stainless steel wire mesh for pressure filtration, and the vacuum degree of vacuum degassing is controlled between -0.08MPa and -0.095MPa for 10-20 minutes.

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