A kind of silver paste for core-through capacitor and preparation method thereof

Abstract

The invention discloses a silver paste for a core-through capacitor and a preparation method thereof. The silver paste is composed of the following raw materials in mass percent: 80-90% of spherical silver powder, 1-4% of lead-free glass powder, 1-4% of metal oxide, and 8-18% of organic carrier. The silver paste is environmentally friendly and lead-free, with high solid content, strong adhesion, high breakdown voltage and low electromagnetic interference (EMI), and its performance fully meets the requirements for use. The preparation method of the invention is simple and suitable for large-scale production. Preparation of organic carrier: Add organic solvent into a stainless steel container, add organic resin, heat up to 70-90°C, after the resin is completely dissolved, cool down to 50-60°C and add surfactant; preparation of lead-free glass powder: mix raw materials Put it in a platinum crucible, melt it at 1000-1400°C, take it out, water quench, pulverize, ball mill, sieve, dry and sieve to get lead-free glass powder; prepare silver paste: silver powder, metal oxide, lead-free glass powder and The organic vehicle is mixed, stirred evenly with a vacuum mixer, and ground on a three-roll mill to a fineness of ≤8 μm to obtain a silver paste.

Description

technical field

[0001] The invention belongs to the technical field of electronic materials, and relates to an environment-friendly electrode silver paste for a core capacitor, and more specifically relates to an electrode silver paste for a core capacitor and a preparation method thereof. Background technique

[0002] High-voltage ceramic core-through capacitors are used to shield microwave clutter generated in magnetrons for microwave ovens and other electrical appliances. They are indispensable electrical components in the microwave oven manufacturing industry. Affected by working conditions, core-through capacitors are subjected to high-temperature shocks. Excessively high temperatures will damage the capacitors, thereby destroying the filtering effect and affecting the work of the entire magnetron.

[0003] In the manufacturing process of high-voltage ceramic core-through capacitors, it is necessary to print a layer of conductive paste on the upper and lower surfaces of...

Examples

Embodiment

[0022] Step A: Select conductive silver powder. The silver powder is spherical monodisperse ultrafine silver powder, the particle size distribution is 0.2-2μm, and the tap density is 3.5-5g / cm 3 , 550 ℃ / 0.5hr burning loss is less than 0.1%. Monodispersed ultra-fine silver powder with high tap density can achieve the goal of good solderability.

[0023] Step B: Preparation of organic vehicle. Weigh 78wt% butyl carbitol, 10wt% benzyl alcohol, 9wt% ethylcellulose, and 3wt% surfactant Tego 655. First add butyl carbitol and terpineol into a stainless steel container and mix, then add ethyl cellulose under stirring, heat up to 70-90°C, after the resin is completely dissolved, cool down to 50-60°C and add surface active Agent Tego 655, filtered to obtain a transparent organic vehicle with good printability.

[0024] Step C: preparing lead-free glass powder. Weigh 65 wt% of bismuth oxide, 8 wt% of silicon dioxide, 12 wt% of boron oxide, 10 wt% of zinc oxide and 5 wt% of dicobal...

technical field

[0001] The invention belongs to the technical field of electronic materials, and relates to an environment-friendly electrode silver paste for a core capacitor, and more specifically relates to an electrode silver paste for a core capacitor and a preparation method thereof. Background technique

[0002] High-voltage ceramic core-through capacitors are used to shield microwave clutter generated in magnetrons for microwave ovens and other electrical appliances. They are indispensable electrical components in the microwave oven manufacturing industry. Affected by working conditions, core-through capacitors are subjected to high-temperature shocks. Excessively high temperatures will damage the capacitors, thereby destroying the filtering effect and affecting the work of the entire magnetron.

[0003] In the manufacturing process of high-voltage ceramic core-through capacitors, it is necessary to print a layer of conductive paste on the upper and lower surfaces of...

Examples

Embodiment

[0022] Step A: Select conductive silver powder. The silver powder is spherical monodisperse ultrafine silver powder, the particle size distribution is 0.2-2μm, and the tap density is 3.5-5g / cm 3 , 550 ℃ / 0.5hr burning loss is less than 0.1%. Monodispersed ultra-fine silver powder with high tap density can achieve the goal of good solderability.

[0023] Step B: Preparation of organic vehicle. Weigh 78wt% butyl carbitol, 10wt% benzyl alcohol, 9wt% ethylcellulose, and 3wt% surfactant Tego 655. First add butyl carbitol and terpineol into a stainless steel container and mix, then add ethyl cellulose under stirring, heat up to 70-90°C, after the resin is completely dissolved, cool down to 50-60°C and add surface active Agent Tego 655, filtered to obtain a transparent organic vehicle with good printability.

[0024] Step C: preparing lead-free glass powder. Weigh 65 wt% of bismuth oxide, 8 wt% of silicon dioxide, 12 wt% of boron oxide, 10 wt% of zinc oxide and 5 wt% of dicobal...