阅读说明：本技术 一种用于5g滤波器的喷涂银浆及其制备方法 (Spraying silver paste for 5G filter and preparation method thereof ) 是由 李罗峰 江志坚 刘友朋 张伟铭 郑京 于 2021-08-25 设计创作，主要内容包括：本发明公开一种用于5G滤波器的喷涂银浆,原料包括分散剂、有机载体、银粉、无机金属助剂、无铅玻璃粉；各组分按照重量份计,分散剂为0.1-5重量份；有机载体为20-35重量份；银粉为60-80重量份；无机金属助剂为0.1-2重量份,无铅玻璃粉为0.5-3重量份,溶剂为60-90重量份。本发明有效解决了膜厚不均匀、起皮起泡问题,拉力小等问题,并且具有良好的喷涂效果。(The invention discloses a spraying silver paste for a 5G filter, which comprises raw materials of a dispersing agent, an organic carrier, silver powder, an inorganic metal auxiliary agent and lead-free glass powder; the dispersant accounts for 0.1 to 5 weight portions of each component; 20-35 parts of organic carrier; 60-80 parts of silver powder; 0.1-2 parts of inorganic metal additive, 0.5-3 parts of lead-free glass powder and 60-90 parts of solvent. The invention effectively solves the problems of uneven film thickness, peeling and bubbling, small tension and the like, and has good spraying effect.)

1. The spraying silver paste for the 5G filter is characterized in that raw materials comprise a dispersing agent, an organic carrier, silver powder, an inorganic metal auxiliary agent, lead-free glass powder and a solvent; the components are calculated according to the parts by weight,

0.1-5 parts by weight of a dispersant;

20-35 parts of organic carrier;

60-80 parts of silver powder;

0.1-2 parts of inorganic metal additive;

0.5-3 parts by weight of lead-free glass powder;

the solvent is 60-90 weight portions.

2. The spray silver paste of claim 1, wherein the components are, in parts by weight,

0.1-2 parts by weight of a dispersant;

20-30 parts of organic carrier;

65-80 parts of silver powder;

0.1-1 weight part of inorganic metal auxiliary agent;

0.5-1.5 parts by weight of lead-free glass powder;

60-90 parts by weight of solvent;

the dispersing agent is selected from polyethylene wax, polyethylene glycol and polyvinyl alcohol;

the organic carrier is a colloidal composite organic carrier formed by swelling at least two resins selected from acrylic resin, polyurethane, phenolic resin, ethyl cellulose, methyl butyl cellulose and polyvinyl butyral (PVB) through a solvent.

3. The spray silver paste of claim 1 or 2, wherein the solvent is selected from at least one of alcohol ester twelve, terpineol, diethylene glycol butyl ether, diethylene glycol dibutyl ether, diethylene glycol, butyl ether acetate, propyl acetate, toluene, n-hexane, cyclohexanone;

the silver powder D50 is 0.5-3 mu m, and the tap density is 1-5 g/cm³D50 is preferably 1-2 μm;

the inorganic metal auxiliary agent is selected from one or more of nano molybdenum powder, nano zinc powder and nano zirconium powder, and the nano molybdenum powder is preferred;

the lead-free glass powder is Bi-Si-B-Zn system glass powder.

4. The spray silver paste of claim 3, wherein the mass ratio of the inorganic metal auxiliary agent to the glass powder is (0.4-0.8): 1.

5. the spray silver paste of claim 2, wherein the component resins in the organic carrier are acrylic resin and cellulose resin, and the mass ratio of the cellulose resin to the acrylic resin is (1-4): 1;

acrylic resin and ethyl cellulose, or acrylic resin and methyl butyl cellulose are preferred.

6. The preparation method of the sprayed silver paste for the 5G filter is characterized by comprising the following steps of:

(1) preparing an organic carrier: preheating a solvent at 60-80 ℃, mixing the resin with the solvent, stirring and dispersing to obtain a swollen colloidal organic carrier;

the solvent is at least one selected from alcohol ester twelve, terpineol, diethylene glycol butyl ether, diethylene glycol dibutyl ether, diethylene glycol butyl ether acetate, propyl acetate, toluene, n-hexane and cyclohexanone;

the organic carrier is a colloidal composite organic carrier formed by swelling at least two resins selected from acrylic resin, polyurethane, phenolic resin, ethyl cellulose, methyl butyl cellulose and polyvinyl butyral (PVB) through a solvent;

(2) mixing a dispersing agent, an inorganic metal auxiliary agent, lead-free glass powder, silver powder and an organic carrier;

(3) and fully emulsifying the mixed material to obtain the spraying silver paste.

7. The method according to claim 6, wherein the component resins in the organic vehicle are acrylic resin and ethyl cellulose, or acrylic resin and methyl butyl cellulose;

the inorganic metal auxiliary agent is selected from one or more of nano molybdenum powder, nano zinc powder and nano zirconium powder, and the nano molybdenum powder is preferred;

the lead-free glass powder is Bi-Si-B-Zn system glass powder.

8. The method according to claim 7, wherein the mass ratio of the ethyl cellulose or the methyl butyl cellulose to the acrylic resin is (1-4): 1;

the mass ratio of the inorganic metal auxiliary agent to the glass powder is (0.4-0.8): 1.

9. the method of claim 6 or 7, wherein the dispersant is selected from polyethylene wax, polyethylene glycol, polyvinyl alcohol; the emulsification process adopts an emulsifying machine for emulsification, the emulsification time is 30min-12h, and the emulsification temperature is 20-40 ℃;

more preferably, the resin of step (1) is first subjected to supercritical CO₂And (3) treatment: treating at 35-40 deg.C and 10-18MPa for 30-60min, and taking out.

10. A5G filter, wherein the 5G filter uses the sprayed silver paste of any one of claims 1 to 5 or the sprayed silver paste prepared by the preparation method of any one of claims 6 to 9.

Technical Field

The invention relates to spraying silver paste for a 5G filter and a preparation method thereof, and belongs to the field of spraying silver paste.

Background

The filter is a frequency-selective device, is an indispensable part of communication equipment, and has a great number of types and forms, and as communication development enters the 5G era, 5G large-scale antenna array (Massive MIMO) technology develops, so that the number of antennas is multiplied, the number of channels reaches 64 or even 128, and thus the demand for the filter is greatly increased.

The base station filter mainly comprises a metal coaxial cavity filter and a ceramic dielectric filter. With the development of 5G technology, ceramic dielectric filters gradually replace traditional metal coaxial cavity filters to become mainstream. In the production process of the ceramic filter, the metallization process plays a role in starting and stopping, and simultaneously determines whether the ceramic filter has the possibility of mass production. The conductive silver paste is one of key materials of the metallization process, and the conductivity and the compactness of the conductive layer of the conductive silver paste have important influence on the performance of the filter.

The conductive silver paste is filling type conductive paste with silver powder as conductive filler and is a key material of the dielectric filter. The silver has the advantages of strong conductive capability, thermal expansion coefficient close to that of a porcelain blank, good thermal stability, capability of directly welding metal on a silver layer and the like, and is considered as the optimal selection of the electrode material of the ceramic dielectric filter.

The silver paste spraying is to spray the silver paste on the surface of the ceramic substrate of the filter by using a spray gun, and a silver film conducting layer is covered on the surface layer of the ceramic through drying and sintering. Silver paste is one of the key materials of the 5G filter, and the conductivity of the silver paste and the compactness of a conductive layer formed by the silver paste have important influence on the performance of the filter, so the silver paste and the preparation process are the key points of the production of the ceramic filter at present. However, the existing conductive paste has the defects of low Q value, poor adhesive force, easiness in insertion loss, thin film layer, weak tension of a silver film, poor welding property of a silver film electrode, uneven film thickness, peeling and bubbling, poor operability and the like, and is not suitable for the requirements of the market on the silver paste for the 5G ceramic filter.

The indexes for measuring the quality of the silver paste of the 5G ceramic filter are as follows: insertion loss, tension, adhesion, weldability, welding resistance and the like. Aiming at the technical problems of the existing conductive silver paste, the development of the conductive silver paste of the 5G ceramic filter, which has the advantages of good operability, excellent weldability and welding resistance, high Q value, small insertion loss and strong adhesive force with a ceramic substrate, has great significance.

Disclosure of Invention

The invention aims to provide spraying silver paste for a 5G filter and a preparation method thereof, and solves the technical problems of low quality factor, weak tensile force of a silver film, poor welding property of a silver film electrode, uneven film thickness, peeling and bubbling of the existing conductive silver paste.

The spraying silver paste for the 5G filter comprises raw material components of a dispersing agent, an organic carrier, silver powder, an inorganic metal auxiliary agent, lead-free glass powder and a solvent.

Wherein, the raw materials for spraying the silver paste are calculated according to the parts by weight,

0.1-5 parts by weight of a dispersant;

20-35 parts of organic carrier;

60-80 parts of silver powder;

0.1-2 parts of inorganic metal additive;

0.5-3 parts by weight of lead-free glass powder;

the solvent is 60-90 weight portions.

Preferably, the first and second electrodes are formed of a metal,

0.1-2 parts by weight of a dispersant;

20-30 parts of organic carrier;

65-80 parts of silver powder;

0.1-1 weight part of inorganic metal auxiliary agent;

0.5-1.5 parts by weight of lead-free glass powder;

the solvent is 60-90 weight portions.

The dispersing agent is selected from polyethylene wax, polyethylene glycol and polyvinyl alcohol; polyethylene wax is preferred.

The organic carrier is a colloidal composite organic carrier formed by swelling at least two resins selected from acrylic resin, polyurethane, phenolic resin, ethyl cellulose, methyl butyl cellulose and polyvinyl butyral (PVB) through a solvent.

The acrylic resin is preferably mixed with a cellulose resin, and specifically, the acrylic resin may be combined with ethyl cellulose or the acrylic resin may be combined with methyl butyl cellulose.

The cellulose-based resin and the acrylic resin in the organic vehicle form the organic vehicle, providing sufficient adhesive strength and excellent long-term stability.

For example, ethyl cellulose has good film forming properties, and acrylic resin has good adhesion to a base material; after the two resins are combined, the dried strength meets the requirement of 4B.

According to the invention, through compounding of the resin, the organic system of the resin is adjusted, the strength of the organic carrier is obviously improved (strength 4B) after drying, the resin can be fully developed in the organic system to form layer-by-layer coating, the slurry can keep stable viscosity, the spraying effect is excellent, and the thickness is uniform without peeling.

The solvent is at least one selected from alcohol ester twelve, terpineol, diethylene glycol butyl ether, diethylene glycol dibutyl ether, diethylene glycol butyl ether acetate, propyl acetate, toluene, n-hexane and cyclohexanone.

The average particle size of the silver powder can be several to several hundred nanometers or several to dozens of micrometers; it is also possible to have a mixture of two or more silver powders of different particle sizes.

The silver powder may have a spherical, granular, flake, or amorphous shape.

Preferably, the silver powder is silver powder with D50 of 0.5-3 μm and tap density of 1-5 g/cm³D50 is preferably 1 to 2 μm.

The inorganic metal auxiliary agent is selected from one or more of nano molybdenum powder, nano zinc powder and nano zirconium powder, and the nano molybdenum powder is preferred.

The lead-free glass powder is preferably Bi-Si-B-Zn system glass powder, and the Bi-Si-B-Zn glass powder comprises the following components in percentage by mass:

bismuth oxide, zinc oxide, silicon dioxide, boron oxide, and one or more selected from the group consisting of lithium oxide, sodium oxide, potassium oxide, magnesium oxide, calcium oxide, strontium oxide, barium oxide, phosphorus oxide, titanium oxide, and nickel oxide.

Compared with other glass powder, the Bi-Si-B-Zn system glass powder disclosed by the invention not only meets the requirements of lead-free glass powder, but also can form a better matching effect with nano molybdenum powder, the pulling-off mode is porcelain-off, the binding force to the perovskite magnesium porcelain body is larger, the pulling force is larger and meets the requirements, the influence on insertion loss is small (0.51-0.57), and the excellent binding strength and conversion efficiency can be ensured.

Preferably, the mass ratio of the inorganic metal auxiliary agent to the glass powder is (0.4-0.8): 1.

further, the invention provides a preparation method of the sprayed silver paste for the 5G filter,

the method specifically comprises the following steps:

(1) preparing an organic carrier: mixing organic resin with a solvent, stirring and dispersing to obtain an organic carrier; preferably, the solvent is preheated at 60-80 ℃, then the organic resin is mixed with the preheated solvent, stirred and dispersed to obtain the organic carrier, and the dissolving efficiency is improved.

The organic carrier is a jelly obtained by stirring and swelling a plurality of resins and solvents in water bath, and the organic resin is at least two selected from acrylic resin, polyurethane, phenolic resin, ethyl cellulose, methyl butyl cellulose and polyvinyl butyral (PVB).

It is preferable that the acrylic resin is compounded with a cellulose-based resin, such as acrylic resin and ethyl cellulose, or acrylic resin and methyl butyl cellulose.

The cellulose-based resin and the acrylic resin in the organic vehicle form a composite organic vehicle, providing sufficient adhesive strength and excellent long-term stability.

In addition, the jelly organic carrier is obtained by swelling in a solvent water bath, and the jelly organic carrier is better in mixing and dispersing performance with subsequent silver powder, metal additives, lead-free glass powder and other materials, so that the spraying effect and the uniformity and the flatness of the slurry are improved.

Preferably, the mass ratio of the cellulose resin (ethyl cellulose or methyl butyl cellulose) to the acrylic resin is (1-4): 1, preferably (2-4): 1.

the solvent is at least one selected from alcohol ester twelve, terpineol, diethylene glycol butyl ether, diethylene glycol dibutyl ether, diethylene glycol butyl ether acetate, propyl acetate, toluene, n-hexane and cyclohexanone.

Optionally, the resin is subjected to supercritical CO prior to swelling₂The surface performance of the resin is optimized by treatment, the subsequent swelling is facilitated, and particularly under the condition that various organic resins are compounded, supercritical CO is adopted₂The treatment is beneficial to improving the compatibility of various resins and improving the fineness of the slurry and the spraying effect.

The specific treatment process comprises the following steps: adding the resin into a supercritical carbon dioxide reactor, introducing carbon dioxide, treating for 30-60min under the conditions that the temperature is controlled to be 35-40 ℃ and the pressure is 10-18MPa, taking out the resin after treatment, and mixing the resin with the (preheated) solvent.

(2) Mixing a dispersing agent, an inorganic metal auxiliary agent, lead-free glass powder, silver powder and an organic carrier;

the silver powder is silver powder with D50 of 0.5-3 mu m and tap density of 1-5 g/cm³D50 is preferably 1 to 2 μm.

The inorganic metal auxiliary agent is selected from one or more of nano molybdenum powder, nano zinc powder and nano zirconium powder, and the nano molybdenum powder is preferred.

The lead-free glass frit is preferably a Bi-Si-B-Zn bulk glass frit.

The Bi-Si-B-Zn system glass powder not only meets the requirements of lead-free glass powder, but also can form better matching effect with nano molybdenum powder, has larger binding force on a perovskite magnesium porcelain body, has larger pulling force to meet the requirements, has small influence on insertion loss (0.51-0.57), and can ensure excellent binding strength and conversion efficiency.

Preferably, the mass ratio of the inorganic metal auxiliary agent to the glass powder is (0.4-0.8): 1.

the dispersing agent is selected from polyethylene wax, polyethylene glycol and polyvinyl alcohol; polyethylene wax is preferred.

(3) And fully emulsifying the mixed material to obtain the spraying silver paste.

The emulsifying process adopts an emulsifying machine for emulsifying, the emulsifying time is 30min-12h, and the emulsifying temperature is 20-40 ℃.

Further, the invention also provides a 5G filter, which uses the silver paste sprayed and coated as described above.

The invention has the beneficial effects that:

1. according to the invention, the composite organic carrier of acrylic resin and cellulose is adopted, and a plurality of resins and solvents are stirred in a water bath and swelled to obtain a jelly, so that the slurry meets the requirements of viscosity and strength, has a good spraying effect, and solves the problems of uneven film thickness and peeling and foaming.

2. According to the invention, the molybdenum powder is added to match with the Bi-Si-B-Zn system glass powder, so that the molybdenum powder and the Bi-Si-B-Zn system glass powder have a synergistic effect, the strength of the slurry is improved, the binding force to the perovskite magnesium ceramic body is higher, the pulling force is higher, the requirement is met, the influence on insertion loss is small, and the problem of small pulling force is solved.

3. The invention uses the dispersion function of the emulsifying machine, so that the slurry is dispersed more uniformly, and the fineness is small, thus being easier to industrialize.

4. Compared with the existing common commercial dispersant, the dispersant of the invention improves the system dispersibility, and is more suitable for a system of a composite organic carrier.

5. According to the invention, by optimizing the use amount of each component of the sprayed silver paste, the maximum utilization of the electrical conductivity and the thermal conductivity of the silver can be realized by using the least silver powder, the performance of the film layer is optimized, and the cost is reduced.

6. The spray silver paste prepared by the invention is particularly suitable for a spray process, and a compact coating can be finally formed on the surface of the ceramic dielectric body after high-temperature welding, and the coating has high conductivity and reduces the dielectric loss of a ceramic filter in the signal transmission frequency process.

7. The spraying silver paste prepared by the invention has good spraying effect, no sagging and no sinking, and good continuous spraying performance; the surface is smooth and flat after sintering, and the density is high; good weldability, strong adhesive force, excellent high-hardness scratch resistance, high temperature resistance, oxidation resistance, acid and alkali resistance and other comprehensive properties.

Drawings

The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the application and together with the description serve to explain the principles of the application.

FIG. 1 is a drawing of a leveling of a sprayed silver paste prepared in example 1 of the present invention.

FIG. 2 is a sintered appearance of the sprayed silver paste prepared in example 1 of the present invention.

FIG. 3 is a drawing of a leveling of a sprayed silver paste prepared in example 2 of the present invention.

FIG. 4 is a sintered appearance of the sprayed silver paste prepared in example 2 of the present invention.

Detailed Description

The present invention will be further described with reference to the following examples, but the present invention is not limited to the following examples.

The experimental methods described in the following examples are all conventional methods unless otherwise specified; the reagents and materials are commercially available, unless otherwise specified.

Example 1

A preparation method of sprayed silver paste for a 5G filter comprises the following steps:

(1) 87.76g of the alcohol ester twelve was placed in a vessel, which was placed in a water bath at 70 ℃ and preheated. 8.73g of ethylcellulose (Iseman small molecule ethylcellulose N) are weighed₄Commercially available) and 3.51g of acrylic resin, adding the acrylic resin into preheated alcohol ester twelve, and dispersing for 1 hour at the rotating speed of 1000R/min to prepare an organic carrier;

(2) adding 0.5g of polyethylene wax, 0.5g of nano molybdenum powder, 1g of Bi-Si-B-Zn system glass powder, 73.7g D50 spherical silver with the particle size of 1.5-2 mu m and 24.5g of prepared organic carrier into a container;

(3) and (3) fully emulsifying the materials in the container for 1 hour by using an emulsifying machine, wherein the obtained spraying silver paste is uniformly dispersed and the fineness is less than 5.

Example 2

A preparation method of sprayed silver paste for a 5G filter comprises the following steps:

(1) will 87.7The alcohol ester twelve, 6g, was placed in a vessel, which was placed in a 70 ℃ water bath and preheated. 8.73g of ethylcellulose (Iseman small molecule ethylcellulose N) are weighed₄Commercially available) and 3.51g of acrylic resin, adding the acrylic resin into preheated alcohol ester twelve, and dispersing for 1 hour at the rotating speed of 1000R/min to prepare an organic carrier;

(2) adding 0.5g of polyethylene wax, 0.6g of nano molybdenum powder, 1.5g of Bi-Si-B-Zn system glass powder, 72.5g of spherical silver with the particle size of 72.5g D50 being 1.5-2 mu m and 24.5g of prepared organic carrier into a container;

(3) and (3) fully emulsifying the materials in the container by using an emulsifying machine, wherein the obtained spraying silver paste is uniformly dispersed and the fineness is less than 5.

Example 3

A preparation method of sprayed silver paste for a 5G filter comprises the following steps:

(1) 87.76g of the alcohol ester twelve was placed in a vessel, which was placed in a water bath at 70 ℃ and preheated. 8.73g of ethylcellulose (Iseman small molecule ethylcellulose N) are weighed₄Commercially available) and 3.51g of acrylic resin, adding the acrylic resin into preheated alcohol ester twelve, and dispersing for 1 hour at the rotating speed of 1000R/min to prepare an organic carrier;

(2) adding 0.5g of polyethylene wax, 0.8g of nano molybdenum powder, 1g of Bi-Si-B-Zn system glass powder, 72.5g D50 spherical silver with the particle size of 1.5-2 mu m and 24.5g of prepared organic carrier into a container;

the other steps are the same as the example 1, and the required spraying silver paste is obtained.

Example 4

A preparation method of sprayed silver paste for a 5G filter comprises the following steps:

(1) 87.76g of the alcohol ester twelve was placed in a vessel, which was placed in a water bath at 70 ℃ and preheated. 8.73g of ethylcellulose (Iseman small molecule ethylcellulose N) are weighed₄Commercially available) and 3.51g of acrylic resin, adding the acrylic resin into preheated alcohol ester twelve, and dispersing for 1 hour at the rotating speed of 1000R/min to prepare an organic carrier;

(2) adding 0.5g of polyethylene wax, 0.9g of nano molybdenum powder, 1g of Bi-Si-B-Zn system glass powder, 72.5g D50 spherical silver with the particle size of 1.5-2 mu m and 24.5g of prepared organic carrier into a container;

the other steps are the same as the example 1, and the required spraying silver paste is obtained.

Example 5

A preparation method of sprayed silver paste for a 5G filter comprises the following steps:

(1) 87.76g of the alcohol ester twelve was placed in a vessel, which was placed in a water bath at 70 ℃ and preheated. 8.73g of ethylcellulose (Iseman small molecule ethylcellulose N) are weighed₄Commercially available) and 3.51g of acrylic resin, adding the acrylic resin into preheated alcohol ester twelve, and dispersing for 1 hour at the rotating speed of 1000R/min to prepare an organic carrier;

(2) replacing polyethylene wax with dispersant polyvinyl alcohol: adding 0.5g of polyvinyl alcohol, 0.5g of nano molybdenum powder, 1g of Bi-Si-B-Zn system glass powder, 72.5g D50 spherical silver with the particle size of 1.5-2 mu m and 24.5g of prepared organic carrier into a container;

the other steps are the same as the example 1, and the required spraying silver paste is obtained.

Example 6

A preparation method of sprayed silver paste for a 5G filter comprises the following steps:

(1) 87.76g of the alcohol ester twelve was placed in a vessel, which was placed in a water bath at 70 ℃ and preheated. 8.73g of ethylcellulose (Iseman small molecule ethylcellulose N) are weighed₄Commercially available) and 3.51g of acrylic resin, adding the acrylic resin into preheated alcohol ester twelve, and dispersing for 1 hour at the rotating speed of 1000R/min to prepare an organic carrier;

(2) replacing Bi-Si-B-Zn by Bi-B-Zn-V system glass powder: adding 0.5g of polyvinyl alcohol, 0.5g of nano molybdenum powder, 1g of Bi-B-Zn-V system glass powder, 72.5g D50 spherical silver with the particle size of 1.5-2 mu m and 24.5g of prepared organic carrier into a container;

the other steps are the same as the example 1, and the required spraying silver paste is obtained.

Example 7

A preparation method of sprayed silver paste for a 5G filter comprises the following steps:

(1) 87.76g of the alcohol ester twelve was placed in a containerIn the middle, the container is placed in a water bath kettle at 70 ℃ for preheating. 8.73g of ethylcellulose (Iseman small molecule ethylcellulose N) are weighed₄Commercially available) and 3.51g of acrylic resin, adding the acrylic resin into preheated alcohol ester twelve, and dispersing for 1 hour at the rotating speed of 1000R/min to prepare an organic carrier;

(2) replacing nano molybdenum powder with nano zinc powder: adding 0.5g of polyvinyl alcohol, 0.5g of nano zinc powder, 1g of Bi-Si-B-Zn system glass powder, 72.5g D50 spherical silver with the particle size of 1.5-2 mu m and 24.5g of prepared organic carrier into a container;

the other steps are the same as the example 1, and the required spraying silver paste is obtained.

Example 8

A preparation method of sprayed silver paste for a 5G filter comprises the following steps:

(1) 87.76g of the alcohol ester twelve was placed in a vessel, which was placed in a water bath at 70 ℃ and preheated. Weighing 10.2g (Iseman small molecule ethyl cellulose N)₄Commercially available) and 2.2g of acrylic resin, adding the acrylic resin into preheated alcohol ester twelve, and dispersing for 1 hour at the rotating speed of 1000R/min to prepare an organic carrier;

the other steps are the same as the example 1, and the required spraying silver paste is obtained.

Example 9

A preparation method of sprayed silver paste for a 5G filter comprises the following steps:

(1) 87.76g of the alcohol ester twelve was placed in a vessel, which was placed in a water bath at 70 ℃ and preheated. 9.8g (Iseman small molecule ethyl cellulose N) are weighed₄Commercially available) and 2.45g of acrylic resin (two ratio 4: 1) adding the mixture into preheated alcohol ester twelve, and dispersing for 1 hour at the rotating speed of 1000R/min to prepare an organic carrier;

the other steps are the same as the example 1, and the sprayed silver paste is obtained.

Example 10

A preparation method of sprayed silver paste for a 5G filter comprises the following steps:

(1) 87.76g of the alcohol ester twelve was placed in a vessel, which was placed in a water bath at 70 ℃ and preheated. 8.1g (Iseman small molecule ethyl cellulose N) is weighed₄Commercially available) and 4.05g of acrylic resin (two ratio 2: 1) adding the mixture into preheated alcohol ester twelve, and dispersing for 1 hour at the rotating speed of 1000R/min to prepare an organic carrier;

the other steps are the same as the example 1, and the sprayed silver paste is obtained.

Example 11

A preparation method of sprayed silver paste for a 5G filter comprises the following steps:

(1) 87.76g of the alcohol ester twelve was placed in a vessel, which was placed in a water bath at 80 ℃ and preheated. Weighing 12.2g of acrylic resin, adding the acrylic resin into preheated alcohol ester twelve, and dispersing for 1 hour at the rotating speed of 1000R/min to prepare an organic carrier; the other steps are the same as the example 1, and the required spraying silver paste is obtained.

The other steps are the same as the example 1, and the required spraying silver paste is obtained.

Example 12

A preparation method of sprayed silver paste for a 5G filter comprises the following steps:

(1) first 8.73g of ethylcellulose (Iseman's small molecule ethylcellulose N)₄Commercially available) and 3.51g of acrylic resin are added into a supercritical carbon dioxide reactor, carbon dioxide is introduced, the mixture is treated by supercritical carbon dioxide for 30min under the conditions that the temperature is 40 ℃ and the pressure is 15MPa, and after the treatment, the pressure is released, and the composite organic resin treated by the supercritical carbon dioxide is taken out;

87.76g of the alcohol ester twelve was then placed in a container, which was placed in a water bath at 70 ℃ and preheated. Weighing the composite organic resin treated by the supercritical carbon dioxide, adding the composite organic resin into preheated alcohol ester twelve, and dispersing for 1 hour at the rotating speed of 1000R/min to prepare an organic carrier;

the steps (2) to (3) are the same as the example 1, and the required spraying silver paste is obtained.

Comparative example 1

The other steps are the same as example 1 except that no nano-molybdenum powder is used in step (2).

Comparative example 2

The other steps are the same as example 1 except that no Bi-Si-B-Zn glass frit is present in step (2).

Comparative example 3

A preparation method of sprayed silver paste for a 5G filter comprises the following steps:

(1) 87.76g of twelve alcohol esters and 8.73g of ethyl cellulose (Iseman's small molecule ethyl cellulose N)₄Commercially available) and 3.51g of acrylic resin, and dispersing at a rotation speed of 1000R/min for 1 hour to prepare an organic carrier;

(2) adding 0.5g of polyethylene wax, 0.3g of nano molybdenum powder, 1g of Bi-Si-B-Zn system glass powder, 73.7g D50 spherical silver with the particle size of 1.5-2 mu m and 24.5g of prepared organic carrier into a container;

(3) and (3) fully emulsifying the material in the container for 1 hour by using an emulsifying machine to obtain the spraying silver paste.

The silver pastes prepared in each example and comparative example are respectively sprayed on a ceramic substrate of a 5G filter, dried at 150 ℃ for 10min and then sintered at 850 ℃ peak temperature in a chain furnace for 10 min.

The silver pastes prepared in the examples and the comparative examples are subjected to performance tests, and the test results are shown in table 1.

In the invention, the method for testing the performance parameters of the silver pastes in the examples and the comparative examples comprises the following steps:

and (3) insertion loss test: and (4) adopting a network screening instrument and taking an average value.

And (3) viscosity testing: adopting leading sound (RION) VT-063 #, temperature: 25 ± 0.2 ℃, rotation speed: 62.5 RPM.

And (3) fineness test: f.o.g. blade gauge (15 μm).

And (3) testing tension: a 2 x 2mm silver layer solder face was made, then a solder terminal for pull-out was made (a hook was formed with a 1mm diameter silver plated copper wire end, and sanded to a flat surface at the end of the hook (to increase the solder area)), and the terminal was soldered to the 2 x 2mm silver layer solder face (as centered as vertical as possible during soldering), and then the solder joint was tested for tensile force using a tensile tester.

Weldability: the method comprises the steps of adopting a bonding pad with the diameter of 6.5mm and the thickness of 0.12mm as the volume of the tin paste, heating a heating platform to 150 ℃, putting a product with the tin paste on the heating platform, setting the heating platform to 260 ℃, observing the change of the tin paste on the surface of the product until soldering tin melts to form a complete and bright tin bead, keeping the complete and bright tin bead for 120 seconds, observing the shrinkage ratio of the tin paste under the area of the bonding pad, and judging that the weldability is poor if the area of the bonding pad has the shrinkage phenomenon of more than 5%.

And (3) testing the grids: and (3) using a hundred-grid cutter to dry the silver-sprayed product to be detected, wherein the width of a cutter edge is 10-12 mm, every 1-1.2 mm is an interval, the total number of the product is 10, when the product is marked down linearly, 10 linear cutter marks with the same interval appear, and when the product is marked down linearly, the product is marked down at the vertical position of the linear cutter marks, the product becomes a 100-grid square with 10 x 10, and when the product is marked down by the hundred-grid cutter, a substrate can be seen, and the silver layer can not be cut.

The 3M adhesive Tape (3M Transparent Tape 600) with the designated brand and model is uniformly stuck to the position of the grid, the adhesive Tape is tightly stuck by pressing down with fingers, and then the adhesive Tape is torn up by instant force, and whether the silver layer is peeled off or not is visually observed.

The test standards need to meet ISO grades: grade 5B, completely smooth cut edges and no falling of grid intersections; 4B grade, wherein small pieces are peeled off at the intersection of the notches, and the actual damage in the grid cutting area is less than or equal to 5 percent; 3B grade, wherein a part of the cut is peeled off at the intersection of the cuts, and the actual damage in the grid cutting area is 5-15%; 2B grade, wherein the intersection of the cuts is partially peeled or entirely peeled, and the actual damage in the grid cutting area is 15-35%; the grade 1B, the intersection of the cuts is partially peeled or peeled in a whole piece, and the actual damage in the grid cutting area is 35-65%; and the 0B grade is that the intersection of the cuts is partially peeled or entirely peeled, and the actual breakage in the grid area is more than 65%.

Table 1 test of silver paste spraying performance

According to the embodiment and the comparative example data, the spraying silver paste prepared by adopting the appropriate dispersant, the inorganic auxiliary agent and the glass powder and the emulsifying machine has the effects of smaller insertion loss and fineness below 5, wherein the problem of small tension is solved by preferably matching the molybdenum powder with the Bi-Si-B-Zn system glass powder; meanwhile, the problems of uneven film thickness and peeling and foaming are solved by virtue of a proper composite organic system, and the coating has good spraying effect, adhesive force and weldability (more than 95%). In addition, after the composite resin is subjected to supercritical treatment and swelling, the drying strength can be improved (namely, the result of a Baige test is 5B), and the spraying effect is excellent.

From the data of the examples, it can be seen that the mass ratio of the inorganic metal auxiliary agent to the glass frit is (0.4-0.8): within the range of 1, the insertion loss, fineness, adhesive force, weldability, hundred-grid experiments and the like of the sprayed silver paste are excellent, and on the contrary, the poor dosage can have certain influence on the fineness, the adhesive force and the like of the paste. Similarly, the proportion of the composite resin after swelling treatment is controlled to be (2-4): the range of 1 is better, otherwise, the silver paste has poorer hundred-lattice test data and obvious shedding and damage.

As can be seen from the comparative example, the resin is not subjected to swelling treatment (comparative example 3), and the silver paste has poor performance in the hundred grid test; comparative example 1, which does not contain an inorganic metal additive, the silver paste has a lower tensile force; the silver paste of comparative example 2, which does not contain glass, has a significantly reduced adhesion and fails to meet the spraying requirements.

The sprayed silver paste of the 5G filter can effectively solve the technical problems of low quality factor, low tensile force of a silver film, poor welding property of a silver film electrode, uneven film thickness, peeling and bubbling of the existing conductive silver paste, and can be suitable for industrial mass production.

In the description herein, reference to the description of the terms "one embodiment/mode," "some embodiments/modes," "example," "specific example," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment/mode or example is included in at least one embodiment/mode or example of the application. In this specification, the schematic representations of the terms used above are not necessarily intended to be the same embodiment/mode or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments/modes or examples. Furthermore, the various embodiments/aspects or examples and features of the various embodiments/aspects or examples described in this specification can be combined and combined by one skilled in the art without conflicting therewith.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present application, "plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

It should be understood by those skilled in the art that the above embodiments are only for clarity of explanation and are not intended to limit the scope of the present application. Other variations or modifications will occur to those skilled in the art based on the foregoing disclosure and are still within the scope of the present application.