阅读说明：本技术 介质滤波器的银层修复用导电材料及其制备方法 (Conductive material for repairing silver layer of dielectric filter and preparation method thereof ) 是由 唐小能 谈正 王飞 杜乐德 于 2021-10-27 设计创作，主要内容包括：本申请公开了一种介质滤波器的银层修复用导电材料及其制备方法,属于通信技术领域。所述导电浆料包括按重量份数计的以下组分：粘结剂8-24份；功能助剂1.3-3.3份；导电剂5-9份；低温合金4-8份；导电银粉65-80份。导电浆料在需要修复的银层表面形成固化膜,导电剂在固化膜中均匀分散,低温合金在导电银粉之间形成金属接触层,因此,固化膜的导电性能优良。导电浆料在180-200℃的温度条件下20-40分钟就可以完全固化,固化温度低、时间短,减少了时间和资源的浪费,不会对介质滤波器内的瓷体的抗热性能造成影响,避免了瓷体产生暗裂纹的风险,经导电浆料修复后的介质滤波器的可靠性与稳定性较好。(The application discloses a conductive material for repairing a silver layer of a dielectric filter and a preparation method thereof, belonging to the technical field of communication. The conductive paste comprises the following components in parts by weight: 8-24 parts of a binder; 1.3-3.3 parts of functional auxiliary agent; 5-9 parts of a conductive agent; 4-8 parts of low-temperature alloy; 65-80 parts of conductive silver powder. The conductive paste forms a cured film on the surface of the silver layer to be repaired, the conductive agent is uniformly dispersed in the cured film, and the low-temperature alloy forms a metal contact layer between the conductive silver powder, so that the conductive performance of the cured film is excellent. The conductive paste can be completely cured within 20-40 minutes at the temperature of 180-200 ℃, the curing temperature is low, the time is short, the waste of time and resources is reduced, the heat resistance of the porcelain body in the dielectric filter is not affected, the risk of dark cracks generated on the porcelain body is avoided, and the reliability and the stability of the dielectric filter repaired by the conductive paste are better.)

1. The conductive paste for repairing the silver layer of the dielectric filter is characterized by comprising the following components in parts by weight:

8-24 parts of binder

1.3-3.3 parts of functional auxiliary agent

5-9 parts of conductive agent

4-8 parts of low-temperature alloy

65-80 parts of conductive silver powder.

2. The conductive paste for repairing silver layer of dielectric filter according to claim 1, wherein said binder comprises at least the following components:

5-14 parts of epoxy resin

3-10 parts of a diluent.

3. The conductive paste for repairing a silver layer of a dielectric filter according to claim 2, wherein:

the epoxy resin comprises at least one of bisphenol A epoxy resin, bisphenol F epoxy resin, acrylic acid modified epoxy resin and alicyclic epoxy resin;

the diluent comprises at least one of ethylene glycol dibutyl ether, bisphenol A acrylate and hydroxyethyl methacrylate.

4. The conductive paste for repairing a silver layer of a dielectric filter according to claim 1, wherein the functional assistant comprises at least the following components:

0.5 to 1.5 portions of curing agent

0.2 to 0.5 portion of dispersant

0.1 to 0.2 portion of flatting agent

0.2 to 0.5 portion of defoaming agent

0.3-0.6 part of thixotropic agent.

5. The conductive paste for repairing a silver layer of a dielectric filter according to claim 4, wherein:

the curing agent is aminated imide or cumenyl cyclopentadienyl iron hexafluorophosphate;

the dispersant comprises at least one of Dispex AA4141, SP717 and DH-6000;

the leveling agent comprises at least one of BYK-333 and TEG 0410;

the antifoaming agent comprises at least one of 750SH, DF 114;

the thixotropic agent comprises at least one of fumed silica, amide wax and bentonite.

6. The conductive paste for repairing a silver layer of a dielectric filter according to claim 1, wherein: the conductive agent includes a mixed slurry of carbon nanotubes and graphene.

7. The conductive paste for repairing a silver layer of a dielectric filter according to claim 1, wherein: the conductive silver powder comprises spherical silver powder and flake silver powder, and the spherical silver powderThe powder has an average particle diameter of 2.5 μm and a tap density of more than 5.5g/cm³(ii) a The flake diameter of the flake silver powder is 5-10 mu m, and the tap density is more than 3g/cm³The mass ratio of the spherical silver powder to the flake silver powder is 70-85: 15-30.

8. A method for preparing a conductive paste for repairing a silver layer of a dielectric filter according to any one of claims 1 to 7, comprising:

preparing 8-24 parts of the binder into epoxy resin slurry;

uniformly stirring the components except the curing agent in the functional auxiliary agent, the conductive agent, the low-temperature alloy, the conductive silver powder and the epoxy resin slurry according to a preset proportion, standing for 10-20 minutes to form a first mixed slurry, and uniformly dispersing the first mixed slurry;

adding 0.5-1.5 parts of the curing agent into the dispersed first mixed slurry to obtain second mixed slurry;

and uniformly stirring the second mixed slurry and filtering to form the conductive slurry.

9. The method of claim 8, wherein when the adhesive comprises 5-14 parts of epoxy resin and 3-10 parts of diluent, the forming 8-24 parts of the adhesive into an epoxy resin paste comprises:

and 5-14 parts of the epoxy resin is dissolved in 3-10 parts of the diluent at 40-60 ℃ to form the epoxy resin slurry.

10. The method according to claim 8, wherein when the functional assistant comprises 0.2-0.5 parts of a dispersant, 0.1-0.2 parts of a leveling agent, 0.2-0.5 parts of an antifoaming agent, and 0.3-0.6 parts of a thixotropic agent, the components of the functional assistant other than the curing agent, the conductive agent, the low-temperature alloy, the conductive silver powder, and the epoxy resin paste are uniformly stirred in a predetermined ratio, comprising:

mixing the dispersing agent, the leveling agent, the defoaming agent, the thixotropic agent, the conductive agent, the low-temperature alloy, the conductive silver powder and the epoxy resin slurry according to a ratio of 0.2-0.5: 0.1-0.2: 0.2-0.5: 0.3-0.6: 5-9: 4-8: 65-80: stirring at a ratio of 10-20.

Technical Field

The embodiment of the application relates to the technical field of communication, in particular to a conductive material for repairing a silver layer of a dielectric filter and a preparation method thereof.

Background

A Dielectric filter (Dielectric Resonator) is constructed by coupling between Dielectric resonators. The dielectric filter has the advantages of high Q value, low insertion loss, small size and light weight, and is widely applied to systems such as wireless base stations, satellite communication, navigation systems, electronic countermeasure and the like. The dielectric resonator may be composed of a ceramic having a dielectric constant 20100 times higher than that of air.

When the medium is ceramic, the medium filter is formed by dry pressing functional ceramic medium powder, sintered at high temperature (1200-1500 ℃), metallized by processes of silver spraying, silver dipping and the like, and tested and debugged to index requirements by a vector network analyzer. Debugging can be achieved by carving or laser etching a part of the silver layer on the side wall or the bottom of the blind hole of the dielectric filter, but the expected requirement can not be met in each debugging, and multiple times of adjustment are sometimes needed to meet the index requirement. When the adjustment is excessive, high-temperature silver paste is needed for repairing, and the ceramic body of the dielectric filter is sintered at high temperature again. However, increasing the number of times of fire over wastes the time and resources for frequency modulation, affects the insertion loss of the product, and affects the thermal shock resistance of the porcelain body, thereby causing the risk of cracking of the porcelain body. For example, if the product has a PCB (Printed Circuit Board) Board, the product is scrapped when the debugging is excessive because the high temperature repair cannot be performed.

Therefore, a conductive paste for repairing a silver layer, which can be used for frequency modulation of a dielectric filter, is urgently needed.

Disclosure of Invention

The embodiment of the application provides a conductive material for repairing a silver layer of a dielectric filter and a preparation method thereof, which are used for solving the problems that when the dielectric filter is repaired by using high-temperature silver paste and sintered at high temperature, frequency modulation time and resources are wasted, insertion loss of a product is influenced, and meanwhile, the thermal vibration resistance of a porcelain body is influenced, so that the crack risk of the porcelain body is caused. The technical scheme is as follows:

in one aspect, a conductive paste for repairing a silver layer of a dielectric filter is provided, the conductive paste at least includes:

8-24 parts of binder

1.3-3.3 parts of functional auxiliary agent

5-9 parts of conductive agent

4-8 parts of low-temperature alloy

65-80 parts of conductive silver powder.

In one possible implementation, the binder comprises at least the following components:

5-14 parts of epoxy resin

3-10 parts of a diluent.

In one possible implementation, the epoxy resin includes at least one of bisphenol a epoxy resin, bisphenol F epoxy resin, acrylic modified epoxy resin, and alicyclic epoxy resin; the diluent comprises at least one of ethylene glycol dibutyl ether, bisphenol A acrylate and hydroxyethyl methacrylate.

In one possible implementation, the functional assistant comprises at least the following components:

0.5 to 1.5 portions of curing agent

0.2 to 0.5 portion of dispersant

0.1 to 0.2 portion of flatting agent

0.2 to 0.5 portion of defoaming agent

0.3-0.6 part of thixotropic agent.

In one possible implementation, the curing agent is an aminated imide or cumeneferrocene hexafluorophosphate. The dispersant comprises at least one of Dispex AA4141, SP717 and DH-6000; the leveling agent comprises at least one of BYK-333 and TEG 0410; the antifoaming agent comprises at least one of 750SH, DF 114; the thixotropic agent comprises at least one of fumed silica, amide wax and bentonite.

In one possible implementation, the conductive additive includes a mixed slurry of carbon nanotubes and graphene.

In one possible implementationThe conductive silver powder comprises spherical silver powder and flake silver powder, the average particle diameter of the spherical silver powder is 2.5 mu m, and the tap density is more than 5.5g/cm³(ii) a The flake diameter of the flake silver powder is 5-10 mu m, and the tap density is more than 3g/cm³The mass ratio of the spherical silver powder to the flake silver powder is 70-85: 15-30.

In one aspect, there is provided a method for preparing a conductive paste for repairing a silver layer of a dielectric filter, the method including:

preparing 8-24 parts of the binder into epoxy resin slurry;

uniformly stirring the components except the curing agent in the functional auxiliary agent, the conductive agent, the low-temperature alloy, the conductive silver powder and the epoxy resin slurry according to a preset proportion, standing for 10-20 minutes to form a first mixed slurry, and uniformly dispersing the first mixed slurry;

adding 0.5-1.5 parts of the curing agent into the dispersed first mixed slurry to obtain second mixed slurry;

and uniformly stirring the second mixed slurry and filtering to form the conductive slurry.

In one possible implementation, when the adhesive includes 5-14 parts of epoxy resin and 3-10 parts of diluent, the preparing 8-24 parts of the adhesive into epoxy resin slurry includes:

and 5-14 parts of the epoxy resin is dissolved in 3-10 parts of the diluent at 40-60 ℃ to form the epoxy resin slurry.

In one possible implementation manner, when the functional assistant includes 0.2 to 0.5 parts of a dispersant, 0.1 to 0.2 parts of a leveling agent, 0.2 to 0.5 parts of an antifoaming agent, and 0.3 to 0.6 parts of a thixotropic agent, the components of the functional assistant except for a curing agent, the conductive agent, the low-temperature alloy, the conductive silver powder, and the epoxy resin paste are uniformly stirred according to a predetermined ratio, and the method includes:

mixing the dispersing agent, the leveling agent, the defoaming agent, the thixotropic agent, the conductive agent, the low-temperature alloy, the conductive silver powder and the epoxy resin slurry according to a ratio of 0.2-0.5: 0.1-0.2: 0.2-0.5: 0.3-0.6: 5-9: 4-8: 65-80: stirring at a ratio of 10-20.

The technical scheme provided by the embodiment of the application has the beneficial effects that at least:

the adhesive forms a curing film on the surface of the silver layer to be repaired, the conductive agent is uniformly dispersed in the curing film, and the low-temperature alloy forms a metal contact layer between the conductive silver powder, so that the conductive performance of the curing film is excellent. The temperature of the conductive paste is low during curing, so that the waste of time and resources is reduced, the heat resistance of the ceramic body in the dielectric filter is not affected, the risk of cracks on the ceramic body is avoided, and the reliability and the stability of the dielectric filter repaired by the conductive paste are good. In addition, the conductive paste can be completely cured at the temperature of 180-200 ℃ for 20-40 minutes, and can be stored for 4 months at about 10 ℃.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is a flow chart of a method for preparing a conductive paste for repairing a silver layer of a dielectric filter according to the present invention;

FIG. 2 is a graph comparing the distribution of Q values before and after high and low temperature cycling and aging experiments;

FIG. 3 is a graph comparing adhesion distribution before and after high and low temperature cycling and aging experiments.

Detailed Description

To make the objects, technical solutions and advantages of the embodiments of the present application more clear, the embodiments of the present application will be further described in detail with reference to the accompanying drawings.

Conductive adhesives are important bonding materials in the electronics industry and generally consist of a conductive filler, a polymer matrix and an auxiliary agent. The dielectric filter needs to meet the requirement of 500 times of high-low cycle and aging test tests under the condition of 45-150 DEG CAnd the like, the existing conductive adhesive can not meet the test requirements, and the requirement of improving the conductive adhesive at 5G (5G)^thGeneration, fifth Generation mobile communication system) reliability on dielectric filters.

The invention provides a conductive paste for repairing a frequency-modulated silver layer of a dielectric filter, which at least comprises the following components in parts by weight:

8-24 parts of binder

1.3-3.3 parts of functional auxiliary agent

5-9 parts of conductive agent

4-8 parts of low-temperature alloy

65-80 parts of conductive silver powder.

In one embodiment, the binder comprises at least the following components:

5-14 parts of epoxy resin

3-10 parts of a diluent.

Wherein the epoxy resin comprises at least one of bisphenol A epoxy resin, bisphenol F epoxy resin, acrylic modified epoxy resin and alicyclic epoxy resin. The diluent comprises at least one of ethylene glycol dibutyl ether, bisphenol A acrylate and hydroxyethyl methacrylate.

In another embodiment, the functional adjuvant comprises at least the following components:

0.5 to 1.5 portions of curing agent

0.2 to 0.5 portion of dispersant

0.1 to 0.2 portion of flatting agent

0.2 to 0.5 portion of defoaming agent

0.3-0.6 part of thixotropic agent.

Wherein the curing agent is aminated imide or cumenyl cyclopentadienyl iron hexafluorophosphate; the dispersant comprises at least one of Dispex AA4141, SP717 and DH-6000; the leveling agent comprises at least one of BYK-333 and TEG 0410; the defoaming agent comprises at least one of 750SH and DF 114; the thixotropic agent comprises at least one of fumed silica, amide wax and bentonite.

Namely, the mass ratio of the epoxy resin, the diluent, the curing agent, the dispersing agent, the flatting agent, the defoaming agent, the thixotropic agent, the conductive agent, the low-temperature alloy and the conductive silver powder is 5-14: 3-10: 0.5-1.5: 0.2-0.5: 0.1-0.2: 0.2-0.5: 0.3-0.6: 5-9: 4-8: 65-80.

In one embodiment, the conductive agent includes a mixed slurry of carbon nanotubes and graphene.

Specifically, the conductive silver powder comprises spherical silver powder and flake silver powder, wherein the spherical silver powder has an average particle diameter of 2.5 μm and a tap density of more than 5.5g/cm³(ii) a The flake diameter of the flake silver powder is 5-10 μm, and the tap density is more than 3g/cm³The mass ratio of the spherical silver powder to the flake silver powder is 70-85: 15-30.

Specifically, the low-temperature alloy refers to an alloy with the sintering temperature of less than 250 ℃. In one example, the low temperature alloy is a tin bismuth alloy (SnBi low temperature alloy).

The invention also provides a preparation method of the electronic paste for repairing the dielectric filter, which comprises the following steps:

s1, preparing 8-24 parts of adhesive into epoxy resin slurry.

Specifically, 5-14 parts of epoxy resin is dissolved in 3-10 parts of diluent at 40-60 ℃ to form epoxy resin slurry.

It can be understood that after the epoxy resin is dissolved in the diluent, the fluidity of the epoxy resin is increased, and the materials are mixed uniformly.

S2, uniformly stirring the components except the curing agent in the functional auxiliary agent, the conductive agent, the low-temperature alloy, the conductive silver powder and the epoxy resin slurry according to a preset proportion, standing for 10-20 minutes to form first mixed slurry, and uniformly dispersing the first mixed slurry.

Specifically, the components of the dispersing agent, the flatting agent, the defoaming agent, the thixotropic agent, the conductive agent, the low-temperature alloy, the conductive silver powder and the epoxy resin slurry are mixed according to the proportion of 0.2-0.5: 0.1-0.2: 0.2-0.5: 0.3-0.6: 5-9: 4-8: 65-80: stirring at a ratio of 10-20.

It is understood that the first mixed slurry may be dispersed using a three-roll mill, and the uniformity of the first mixed slurry may be increased.

S3, adding 0.5-1.5 parts of curing agent into the dispersed first mixed slurry to obtain a second mixed slurry.

And S4, uniformly stirring the second mixed slurry, and filtering to form the conductive slurry.

It is understood that, when the second mixed slurry is stirred, a centrifugal stirrer may be used for stirring.

From the above description, the beneficial effects of the present invention are: the conductive paste forms a cured film on the surface of the silver layer to be repaired, the conductive agent is uniformly dispersed in the cured film, and the low-temperature alloy forms a metal contact layer between the conductive silver powder, so that the conductive performance of the cured film is excellent. The temperature of the binder is low during curing, so that the waste of time and resources is reduced, the heat resistance of the ceramic body in the dielectric filter is not affected, the risk of cracks on the ceramic body is avoided, and the reliability and the stability of the dielectric filter repaired by the conductive paste are good.

The following three examples are given as examples to illustrate the preparation of the conductive paste.

Example 1

10 parts of bisphenol A epoxy resin is added into 4 parts of bisphenol A acrylate and 4 parts of hydroxyethyl methacrylate, and the mixture is stirred and dispersed until the mixture is clear and transparent.

Weighing 10 parts of epoxy resin solution, 0.4g of Dispex AA4141, 0.3g of DF114, 0.2g of leveling agent TEG0410, 0.4g of bentonite, 5 parts of conductive agent, 5 parts of SnBi alloy, 64g of spherical silver powder and 16g of flaky silver powder, stirring for 2min by a centrifugal stirrer 1500r/min, and standing for 10 min.

And dispersing the stirred slurry for 8 times by using a three-roll grinder S65 according to a gap 30/15 and a rotating speed of 300r/min, and then dispersing for 4 times according to a gap 15/8 and a rotating speed of 400 r/min.

And adding 0.4g of aminated imide and 10 parts of epoxy resin solution into the dispersed slurry, stirring for 2min at 800r/min by using a centrifugal stirrer, and filtering to obtain the conductive slurry for repairing the silver layer of the dielectric filter.

Spraying the prepared conductive slurry for repairing the silver layer of the dielectric filter onto the single-cavity ceramic medium by using a semi-automatic spraying machine, drying at 180 ℃ for 30min, controlling the thickness to be 12-18 mu m and the Q value of the single cavityMean value of 1535 and adhesion mean value of 15N/mm²And after 500 times of high-low temperature circulation and aging experiment tests, the electrical property and the adhesion property are not obviously deteriorated.

Example 2

6 parts of bisphenol A epoxy resin and 4 parts of bisphenol F epoxy resin are added into 5 parts of propylene glycol dibutyl ether, and the mixture is stirred and dispersed until the mixture is clear and transparent.

14 parts of epoxy resin solution, 0.5g of DH-6000, 0.3g of 750SH, 0.2g of BYK-333, 0.6g of fumed silica, 6 parts of conductive agent, 7 parts of SnBi alloy, 60g of spherical silver powder and 20g of flake silver powder are weighed, stirred for 2min by a centrifugal stirrer 1500r/min and kept stand for 10 min.

And dispersing the stirred slurry for 8 times by using a three-roll grinder S65 according to a gap 30/15 and a rotating speed of 300r/min, and then dispersing for 4 times according to a gap 15/8 and a rotating speed of 400 r/min.

And adding 1.5g of cumenyl cyclopentadienyl iron hexafluorophosphate into the dispersed slurry, stirring for 2min at 800r/min by using a centrifugal stirrer, and filtering to obtain the conductive slurry for repairing the silver layer of the dielectric filter.

Spraying the prepared conductive slurry for repairing the silver layer of the dielectric filter onto the single-cavity ceramic medium by using a semi-automatic spraying machine, drying at 200 ℃ for 20min, controlling the thickness to be 12-18 mu m, controlling the mean value of the Q value of the single cavity to be 1650 and the mean value of the adhesive force to be 15.5N/mm²And after 500 times of high-low temperature circulation and aging experiment tests, the electrical property and the adhesion property are not obviously deteriorated.

Example 3

Adding 8 parts of acrylic acid modified epoxy resin and 6 parts of alicyclic epoxy resin into 7 parts of bisphenol A acrylate and 4 parts of hydroxyethyl methacrylate, and stirring and dispersing until the mixture is clear and transparent.

12 parts of an epoxy resin solution, 0.4g of SP717, 0.2g of 750SH and 0.3g of DF114, 0.3g of amide wax, 10 parts of a conductive agent, 4 parts of SnBi alloy, 55g of spherical silver powder and 15g of flake silver powder were weighed out, stirred at 1500 rpm in a centrifugal stirrer for 2 minutes and left to stand for 10 minutes.

And dispersing the stirred slurry for 8 times by using a three-roll grinder S65 according to a gap 30/15 and a rotating speed of 300r/min, and then dispersing for 4 times according to a gap 15/8 and a rotating speed of 400 r/min.

And adding 0.6g of benzyldimethylammonium phenyl silicate and 0.2g of aminated imide into the dispersed slurry, stirring for 2min at 800r/min by using a centrifugal stirrer, and filtering to obtain the conductive slurry for repairing the silver layer of the dielectric filter.

Spraying the prepared conductive slurry for repairing the silver layer of the dielectric filter onto the single-cavity ceramic medium by using a semi-automatic spraying machine, drying at 190 ℃ for 30min, controlling the thickness to be 12-18 mu m, controlling the mean value of the Q values of the single cavities to be 1600 and the mean value of the adhesive force to be 15.3N/mm²And after 500 times of high-low temperature circulation and aging experiment tests, the electrical property and the adhesion property are not obviously deteriorated.

The first … … and the second … … are only used for name differentiation and do not represent how different the importance and position of the two are.

The above description should not be taken as limiting the embodiments of the present application, and any modifications, equivalents, improvements, etc. made within the spirit and principle of the embodiments of the present application should be included in the scope of the embodiments of the present application.