WO2018024073A1

WO2018024073A1 - Heat-dissipating type conductive silver paste and preparation method therefor

Info

Publication number: WO2018024073A1
Application number: PCT/CN2017/091978
Authority: WO
Inventors: 刘若鹏; 隋爱国; 李雪
Original assignee: 深圳光启高等理工研究院
Priority date: 2016-08-04
Filing date: 2017-07-06
Publication date: 2018-02-08
Also published as: CN107686705A

Abstract

The invention provides a heat-dissipating type conductive silver paste and a preparation method therefor. The heat-dissipating type conductive silver paste is prepared from 100 parts of a resin mixture, 100 to 500 parts of silver powder and 10 to 100 parts of graphene according to parts by mass. Specifically, the resin mixture is obtained by mixing a resin, a curing agent and a silane coupling agent in proportion, and the resin mixture is degassed and then mixed with silver powder and graphene. By doping graphene with high thermal conductivity into the conductive silver paste, heat dissipation property of the conductive silver paste is greatly improved, and the defect that the existing silver paste has poor heat dissipation property is solved. The heat-dissipatingl conductive silver paste provided is mainly used for conductive bonding among objects and can improve the heat dissipation property of the adhesive, and can be widely used in the fields such as electronics, information, electroplating and so on.

Description

Heat-dissipating conductive silver glue and preparation method thereof

[0001] The present invention relates to the field of composite materials, and more particularly to a heat-dissipating conductive silver paste and a preparation method thereof

[0002] The conductive silver-glued conductive silver paste bonds the conductive particles together by the bonding of the matrix resin to form a conductive path to realize the conductive connection of the material to be bonded. Since the matrix resin of the conductive silver paste is an adhesive. At the same time, due to the miniaturization and miniaturization of electronic components, and the rapid development of high density and high integration of printed circuit boards, conductive silver paste can be made into a paste to achieve high line resolution. Conductive silver paste has been widely used in liquid crystal displays (LCDs), light-emitting diodes (LEDs), integrated circuit (IC) chips, printed circuit board assemblies (PCBA;), lattice blocks, ceramic capacitors, thin film switches, smart cards, RF Identifying the packaging and bonding of electronic components and components has gradually replaced the trend of traditional soldering.

technical problem

[0003] Conventional conductive silver paste is mostly made of sheet-like or dendritic silver powder, and is made of a certain proportion of epoxy resin, curing agent dispersant, etc., and the conductive silver paste produced has poor thermal conductivity, especially in As a binder for electronic packaging devices, it tends to accumulate heat during the operation of the device, causing an increase in temperature, which ultimately affects conductivity and bonding strength.

Problem solution

Technical solution

In view of the above, the present invention provides a heat-dissipating conductive silver paste and a preparation method thereof, which can greatly improve the heat dissipation of the conductive silver paste by the cumbersomeness, so as to solve the thermal conductivity of the conductive silver paste in the prior art. Poor question.

[0005] According to an aspect of the present invention, a heat-dissipating conductive silver paste is provided, which is prepared by mass parts of 100 parts of a resin mixture, 100-500 parts of silver powder, and 10 to 100 parts of graphene. Made.

[0006] In the above heat-dissipating conductive silver paste, the resin mixture includes 100 parts of an epoxy resin, 5 to 20 parts of a curing agent, 2 to 10 parts of a silane coupling agent, and 5 to 25 parts of an inactive diluent.

[0007] In the above heat-dissipating conductive silver paste, the curing agent is an imidazole curing agent. [0008] In the above heat-dissipating conductive silver paste, the epoxy resin is a bisphenol A type epoxy resin.

In the above heat-dissipating conductive silver paste, the non-reactive diluent is selected from one or a combination of ethanol, acetone, and toluene.

[0010] According to another aspect of the present invention, a method for preparing a heat-dissipating conductive silver paste is provided, comprising: mixing a resin, a curing agent, and a silane coupling agent in proportion to obtain a resin mixture; and removing the resin mixture from the bubble And then, the resin mixture is mixed with silver powder and graphene to obtain a heat-dissipating conductive silver paste.

[0011] In the above method, a step of mixing the resin, the curing agent, and the silane coupling agent in proportion is carried out in a stirrer.

[0012] In the above method: the stirring speed of the agitator is 500 to 2000 rpm, and the stirring time is 10 to 30 minutes.

[0013] In the above method, air bubbles in the resin mixture are removed by vacuum agitation.

[0014] In the above method, the speed of vacuum stirring is 500 to 2000 rpm, and the stirring time is 10 to 60 minutes.

[0015] In the above method, 100 parts of the resin mixture, 100 to 500 parts of silver powder, and 10 to 100 parts of graphene are mixed to obtain a heat-dissipating type conductive silver paste, wherein the parts of each component are parts by mass.

In the above method, the resin mixture is mixed with silver powder or graphene by grinding the resin mixture with silver powder or graphene in a three-roll mill.

[0017] In the above method, the grinding time is 0.5 to 2 hours.

[0018] In the above method, 100 parts of epoxy resin, 5-20 parts of curing agent, 2-10 parts of silane coupling agent, and 5~2

5 parts of the non-reactive diluent are mixed to obtain a resin mixture, wherein the parts of each component are parts by mass

[0019] In the above method, the curing agent is an imidazole curing agent.

[0020] In the above method, the epoxy resin is a bisphenol A type epoxy resin.

[0021] In the above method, the non-reactive diluent is selected from one or a combination of ones of ethanol, acetone, and toluene.

Advantageous effects of the invention

Beneficial effect

[0022] The present invention greatly improves the conductivity by dispersing graphene having a high thermal conductivity into the conductive silver paste. The heat dissipation of the silver glue solves the defect that the existing silver glue has poor heat dissipation. The heat-dissipating conductive silver glue provided by the invention is mainly used for conductive bonding between objects, can improve the heat dissipation of the adhesive, and can be widely applied to industries such as electronics, information, electroplating and the like.

Brief description of the drawing

DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings to be used in the embodiments will be briefly described below. Obviously, the drawings in the following description are only the present drawings. Some embodiments of the invention may be obtained by those of ordinary skill in the art from the drawings without departing from the scope of the invention.

1 is a flow chart of a method for preparing a heat-dissipating conductive silver paste according to an embodiment of the present invention.

Embodiments of the invention

[0025] The technical solutions in the embodiments of the present invention will be clearly and completely described in the following with reference to the accompanying drawings in the embodiments of the present invention. It is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. example. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention are within the scope of the present invention.

Method for preparing heat-dissipating conductive silver paste

[0027] As shown in step S101 of Fig. 1, the resin, the curing agent, and the silane coupling agent are mixed in proportion to obtain a resin mixture. In a preferred embodiment of the present invention, in the mixing step, the ratio of each component is 100 parts epoxy resin, 5-20 parts curing agent, 2-10 parts silane coupling agent, and 5-25 parts of non-reactive diluent. , wherein the parts of each component are parts by mass. Preferably, in the agitator, the mixing step is carried out, the stirring speed of the agitator is set to 500 to 2000 rpm, and the mixing time is 10 to 60 minutes. Among them, the curing agent is an imidazole curing agent, and other types of curing agents can also be used. The epoxy resin is selected from commercially available bisphenol A type epoxy resins, but is not limited to bisphenol A type epoxy resins. The non-reactive diluent is selected from one or more of the group consisting of ethanol, acetone, and toluene.

[0028] As shown in step S103 of FIG. 1, the resin mixture is taken out of the bubble. In this step, preferably, the bubbles in the resin mixture are removed by vacuum agitation, wherein the vacuum stirring speed is 500 to 2000 rpm, and the stirring time is 10 to 60 minutes. As shown in step S105 of Fig. 1, the resin mixture is then mixed with silver powder and graphene to obtain a heat-dissipating conductive silver paste. In this step, the ratio of each component is: 100 parts of a resin mixture, 100 to 500 parts of silver powder, and 10 to 100 parts of graphene, wherein the parts of each component are parts by mass. The silver powder is preferably flake silver powder. In a preferred embodiment, the resin mixture and the silver powder and graphene are added to a three-roll mill, and ground for 0.5 to 2 hours for dispersion to achieve mixing of the resin mixture with the silver powder and graphene, thereby producing a final heat-dissipating conductive material. Silver glue. Single-layer graphene has a thermal conductivity of up to 5300 W/mk, which is 13 times that of metallic copper.

[0030]

Embodiment 1

[0032] 100 parts of commercially available bisphenol A type epoxy resin, 5 parts of imidazole curing agent, 10 parts of silane coupling agent and 5 parts of inactive diluent ethanol were added to the stirred vessel at 500 rpm. Stirring at a stirring speed of 30 minutes for a minute to obtain a resin mixture;

[0033] The resin mixture is degassed by vacuuming, wherein the stirring speed is 500 rpm, and the stirring is performed for 60 minutes;

[0034] 100 parts of the resin mixture after the bubbles were taken out and 100 parts of the flake silver powder and 10 parts of graphene were placed in a three-roll mill, and the mixture was ground for 0.5 hours to be dispersed, and uniformly mixed to obtain a heat-dissipating conductive silver paste.

[0035] Example 2

[0036] 100 parts of a commercially available bisphenol A type epoxy resin, 20 parts of an imidazole type curing agent, 2 parts of a silane coupling agent, and 25 parts of an inert diluent acetone were added to a stirred container at 2000 rpm / Stirring at a stirring speed of 10 minutes for 10 minutes to obtain a resin mixture;

[0037] The resin mixture is degassed by vacuuming, wherein the stirring speed is 2000 rpm, and the stirring is 10 minutes;

[0038] 100 parts of the resin mixture after the bubbles were taken out and 500 parts of the flake silver powder and 100 parts of graphene were placed in a three-roll mill, and the mixture was ground for 2 hours to be dispersed, and uniformly mixed to obtain a heat-dissipating type conductive silver paste.

Example 3

[0040] 100 parts of a commercially available bisphenol A type epoxy resin, 10 parts of an imidazole curing agent, 5 parts of a silane coupling agent, and 25 parts of an inert diluent acetone were added to a stirred container at 1500 rpm / Stirring at a stirring speed of 20 minutes for a minute to obtain a resin mixture; [0041] The resin mixture is degassed by vacuuming, wherein the stirring speed is 1000 rpm, and the stirring is performed for 30 minutes;

[0042] 100 parts of the resin mixture after the bubbles were taken out and 200 parts of the flake silver powder and 50 parts of graphene were placed in a three-roll mill, and the mixture was ground for 1 hour to be dispersed, and uniformly mixed to obtain a heat-dissipating type conductive silver paste.

Embodiment 4

[0044] 100 parts of commercially available bisphenol A type epoxy resin, 15 parts of imidazole curing agent, 4 parts of silane coupling agent and 15 parts of inactive diluent toluene were added to the stirred vessel at 1000 rpm / Stirring at a stirring speed of 25 minutes for a minute to obtain a resin mixture;

[0045] The resin mixture is degassed by vacuuming, wherein the stirring speed is 1500 rpm, and the stirring is performed for 40 minutes;

[0046] 100 parts of the resin mixture after the bubbles were taken out and 400 parts of the flake silver powder and 80 parts of graphene were placed in a three-roll mill, and the mixture was ground for 1.5 hours to be dispersed, and uniformly mixed to obtain a heat-dissipating type conductive silver paste.

Example 5

[0048] 100 parts of commercially available bisphenol A type epoxy resin, 8 parts of imidazole curing agent, 6 parts of silane coupling agent and 20 parts of inactive diluent toluene were added to the stirred vessel at 1000 rpm / Stirring at a stirring speed of 25 minutes for a minute to obtain a resin mixture;

[0049] The resin mixture is degassed by vacuuming, wherein the stirring speed is 800 rpm, and the stirring is performed for 50 minutes;

[0050] 100 parts of the resin mixture after degassing was added to 120 parts of flake silver powder and 60 parts of graphene to a three-roll mill, and after grinding for 2 hours, the mixture was uniformly dispersed to obtain a heat-dissipating conductive silver paste.

[0051] The conductive silver paste obtained in the above examples was cured at a temperature of 100 ° C for 2 hours, and then subjected to performance test. It can be seen from the test results that the volume resistivity of the conductive silver paste obtained in the above embodiment is 0.00001~0.

00015 ohm.cm, thermal conductivity 2~10W/mk. It can be seen from the test results that the heat-dissipating conductive silver paste of the present invention has good electrical conductivity and good heat dissipation performance.

[0052] The invention is characterized in that the graphene having a high thermal conductivity is miserable into the conductive silver paste, thereby greatly improving the heat dissipation of the conductive silver paste, and solving the defect that the existing silver gel has poor heat dissipation. The heat-dissipating conductive silver glue provided by the invention is mainly used for conductive bonding between objects, can improve the heat dissipation of the adhesive, and can be widely applied to industries such as electronics, information, electroplating and the like. The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalents, improvements, etc., which are within the spirit and scope of the present invention, should be included in the scope of the present invention. within.

Claims

Claim

[Claim 1] A heat-dissipating conductive silver paste characterized by being prepared from 100 parts by mass of a resin mixture, 100 to 500 parts of silver powder, and 10 to 100 parts of graphene in parts by mass.

[Claim 2] The heat-dissipating conductive silver paste according to claim 1, wherein the resin mixture comprises 100 parts of an epoxy resin, 5 to 20 parts of a curing agent, 2 to 10 parts of a silane coupling agent, and 5 ~25 parts of inactive diluent.

[Claim 3] The heat-dissipating conductive silver paste according to claim 2, wherein the curing agent is an imidazole curing agent.

The heat-dissipating conductive silver paste according to claim 2, wherein the epoxy resin is a bisphenol A-type epoxy resin.

[Claim 5] The heat-dissipating conductive silver paste according to claim 2, wherein the inert diluent comprises one or a combination of ethanol, acetone, and toluene.

[Claim 6] A method for preparing a heat-dissipating conductive silver paste, comprising:

Mixing the resin, the curing agent, and the silane coupling agent in proportion to obtain a resin mixture; removing the resin mixture from the bubbles;

Subsequently, the resin mixture is mixed with silver powder or graphene to obtain the heat-dissipating conductive silver paste.

[Claim 7] The method according to claim 6, wherein in the agitator, the resin is implemented

And a step of mixing the curing agent and the silane coupling agent in proportion.

[Claim 8] The method according to claim 7, wherein the stirring speed of the agitator is 5

00~2000 rpm, stirring for 10~30 minutes.

[Claim 9] The method according to claim 6, wherein the bubbles in the resin mixture are removed by vacuum stirring.

[Claim 10] The method according to claim 9, wherein the speed of the vacuum stirring is 5

00~2000 rev / min, stirring for 10 to 60 minutes.

[Claim 11] The method according to claim 6, wherein 100 parts of the resin mixture, 100~

500 parts of silver powder and 10 to 100 parts of graphene are mixed to obtain the heat-dissipating conductive silver glue

Wherein the parts of each component are parts by mass.

[Claim 12] The method according to claim 6, wherein the resin mixture and the silver powder and graphene are carried out by grinding the resin mixture with silver powder and graphene in a three-roll mill. The step of mixing.

[Claim 13] The method according to claim 12, wherein the grinding time is 0.5 to 2 hours.

[Claim 14] The method according to claim 6, wherein 100 parts of the epoxy resin, 5 to 20 parts of the curing agent, 2 to 10 parts of the silane coupling agent, and 5 to 25 parts of the inactive diluent are used. The mixture is obtained to obtain the resin mixture, wherein the parts of each component are parts by mass.

[Claim 15] The method according to claim 14, wherein the curing agent is an imidazole curing agent.

[Claim 16] The method according to claim 14, wherein the epoxy resin is a bisphenol A type epoxy resin.

[Claim 17] The method according to claim 14, wherein the non-reactive diluent is one or more selected from the group consisting of ethanol, acetone, and toluene.