CN102888204A - Novel conductive adhesive for capacitor and capacitor adopting the novel conductive adhesive - Google Patents

Novel conductive adhesive for capacitor and capacitor adopting the novel conductive adhesive Download PDF

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Publication number
CN102888204A
CN102888204A CN2011102030154A CN201110203015A CN102888204A CN 102888204 A CN102888204 A CN 102888204A CN 2011102030154 A CN2011102030154 A CN 2011102030154A CN 201110203015 A CN201110203015 A CN 201110203015A CN 102888204 A CN102888204 A CN 102888204A
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silver
electroconductive binder
electrical condenser
particle
nonmetal
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陈长敬
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Ablestik Shanghai Ltd
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Ablestik Shanghai Ltd
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Priority to CN2011102030154A priority Critical patent/CN102888204A/en
Priority to TW101123990A priority patent/TW201306050A/en
Priority to PCT/CN2012/078872 priority patent/WO2013010492A1/en
Publication of CN102888204A publication Critical patent/CN102888204A/en
Pending legal-status Critical Current

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    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09JADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J9/00Adhesives characterised by their physical nature or the effects produced, e.g. glue sticks
    • C09J9/02Electrically-conducting adhesives
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08GMACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G59/00Polycondensates containing more than one epoxy group per molecule; Macromolecules obtained by polymerising compounds containing more than one epoxy group per molecule using curing agents or catalysts which react with the epoxy groups
    • C08G59/18Macromolecules obtained by polymerising compounds containing more than one epoxy group per molecule using curing agents or catalysts which react with the epoxy groups ; e.g. general methods of curing
    • C08G59/40Macromolecules obtained by polymerising compounds containing more than one epoxy group per molecule using curing agents or catalysts which react with the epoxy groups ; e.g. general methods of curing characterised by the curing agents used
    • C08G59/42Polycarboxylic acids; Anhydrides, halides or low molecular weight esters thereof
    • C08G59/4215Polycarboxylic acids; Anhydrides, halides or low molecular weight esters thereof cycloaliphatic
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09JADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J163/00Adhesives based on epoxy resins; Adhesives based on derivatives of epoxy resins
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09JADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J4/00Adhesives based on organic non-macromolecular compounds having at least one polymerisable carbon-to-carbon unsaturated bond ; adhesives, based on monomers of macromolecular compounds of groups C09J183/00 - C09J183/16
    • C09J4/06Organic non-macromolecular compounds having at least one polymerisable carbon-to-carbon unsaturated bond in combination with a macromolecular compound other than an unsaturated polymer of groups C09J159/00 - C09J187/00
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01GCAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
    • H01G9/00Electrolytic capacitors, rectifiers, detectors, switching devices, light-sensitive or temperature-sensitive devices; Processes of their manufacture
    • H01G9/004Details
    • H01G9/008Terminals
    • H01G9/012Terminals specially adapted for solid capacitors
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01GCAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
    • H01G9/00Electrolytic capacitors, rectifiers, detectors, switching devices, light-sensitive or temperature-sensitive devices; Processes of their manufacture
    • H01G9/004Details
    • H01G9/04Electrodes or formation of dielectric layers thereon
    • H01G9/042Electrodes or formation of dielectric layers thereon characterised by the material
    • H01G9/0425Electrodes or formation of dielectric layers thereon characterised by the material specially adapted for cathode
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01GCAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
    • H01G9/00Electrolytic capacitors, rectifiers, detectors, switching devices, light-sensitive or temperature-sensitive devices; Processes of their manufacture
    • H01G9/15Solid electrolytic capacitors
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08FMACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F220/00Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride ester, amide, imide or nitrile thereof
    • C08F220/02Monocarboxylic acids having less than ten carbon atoms; Derivatives thereof
    • C08F220/10Esters
    • C08F220/12Esters of monohydric alcohols or phenols
    • C08F220/16Esters of monohydric alcohols or phenols of phenols or of alcohols containing two or more carbon atoms
    • C08F220/18Esters of monohydric alcohols or phenols of phenols or of alcohols containing two or more carbon atoms with acrylic or methacrylic acids
    • C08F220/1811C10or C11-(Meth)acrylate, e.g. isodecyl (meth)acrylate, isobornyl (meth)acrylate or 2-naphthyl (meth)acrylate
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08FMACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F222/00Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a carboxyl radical and containing at least one other carboxyl radical in the molecule; Salts, anhydrides, esters, amides, imides, or nitriles thereof
    • C08F222/10Esters
    • C08F222/1006Esters of polyhydric alcohols or polyhydric phenols
    • C08F222/102Esters of polyhydric alcohols or polyhydric phenols of dialcohols, e.g. ethylene glycol di(meth)acrylate or 1,4-butanediol dimethacrylate

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Materials Engineering (AREA)
  • Conductive Materials (AREA)
  • Adhesives Or Adhesive Processes (AREA)

Abstract

The invention provides a novel conductive adhesive for a capacitor and a capacitor using the novel conductive adhesive. The novel conductive adhesive comprises an epoxy resin, epoxy resin curing agents, silver powder and nonmetallic silver-plated particles, or comprises vinyl resins, a peroxide initiator, silver powder and nonmetallic silver-plated particles.

Description

The electroconductive binder and the associated capacitor that are used for electrical condenser
Technical field
The present invention relates to the electroconductive binder for electrical condenser, also relate to the electrical condenser that uses described electroconductive binder.
Background technology
Electroconductive binder can be widely used under lower temperature or normal temperature components and parts are welded.Than traditional soldering and use solder containing pb, use electroconductive binder to have the advantages such as easy to operate, that equipment simple, pollution is little.
Electrically conducting adhesive mainly is comprised of conductive filler material, resin, solidifying agent and additive.
For the electroconductive binder that is used for electrical condenser, bond properties, electroconductibility and reliability (comprising hydrothermal stability) are vital.In addition, how under the prerequisite that guarantees these key propertys, reduce the cost of electroconductive binder, and the production cost that reduces thus electrical condenser also is the industry common concern.
The at present commercially available electroconductive binder that is used for electrical condenser mainly is the electroconductive binder that uses silver powder.Silver copper-clad electroconductive binder is the electroconductive binder of studying at most except the electroconductive binder that uses silver powder at present.
Use the electroconductive binder (being commonly called as elargol) of silver powder can realize stable adhesion, effectively reduced the equivalent series resistance of electrolytic condenser, and stable performance.But international silver-colored valency is high for a long time, in present silver-colored valency 29 $/Toz, and the cost of fine silver conductive filler material the chances are 1000 $/kg.Cause thus the elargol price high, the electrical condenser that causes using elargol to make does not have competitive edge owing to cost is too high.
As for silver-colored copper-clad filler; although it has reduced the cost of electroconductive binder; but be subjected to the restriction of electroplating technology; Copper Powder Surface is difficult to cover fully with silver; and exposed copper chemical property is very active; be easy to be oxidized to cupric oxide, thereby cause the electrical and thermal conductivity performance of electroconductive binder sharply to descend, so that its practical application is had a strong impact on.
Up to now, there is no at capacitor area and use nonmetal silver-plated filler to prepare the report of electroconductive binder.Even if be all the used in electronic industry electroconductive binder, because the specific environment of its application is different, prescription and the preparation process of electroconductive binder often also differ widely.
Therefore, be necessary to develop a kind of electroconductive binder that is applicable to electrical condenser.Such tackiness agent should possess excellent adhesiveproperties, electroconductibility and comprise the reliability of hydrothermal stability, and with low cost.
Summary of the invention
For problems of the prior art, the invention provides the novel conductive tackiness agent for electrical condenser.
According to an aspect of the present invention, provide a kind of electroconductive binder for electrical condenser, it comprises: the Resins, epoxy of 10~60 % by weight; 0.5 the epoxy curing agent of~6 % by weight; The silver powder particles of 0~60 % by weight; Nonmetal silver-plated particle with 15~50 % by weight.
According to a further aspect in the invention, provide a kind of electroconductive binder for electrical condenser, it comprises: the Vinylite of 10~40 % by weight; The peroxide initiator of 0~2 % by weight; The silver powder particles of 0~60 % by weight; Nonmetal silver-plated particle with 15~50 % by weight.
In the present invention, the non-metallic material in the nonmetal silver-plated particle can be to be selected from glass, boron nitride, calcium carbonate, carbon black, carbon fiber, aluminum oxide and the polymer materials one or more.
Not only conductivity is excellent by electroconductive binder provided by the invention, and has high stability under hygrothermal environment.Electroconductive binder of the present invention also has easy preparation, the convenient use, and advantage with low cost.
The present invention also provides the electrical condenser that uses above-mentioned electroconductive binder, and described electrical condenser has used described electroconductive binder at least between its subelement.
The electrical condenser of the above-mentioned electroconductive binder of use of the present invention comprises aluminium electrolutic capacitor, tantalum electrolytic capacitor and niobium electrolytic capacitor.
The following explanation of reference, embodiment and the claims of enclosing, various further features of the present invention, aspect and advantage can become more apparent.
Embodiment
Unless otherwise defined, all technology used herein have the identical implication of usually understanding with those skilled in the art of the invention with scientific terminology.If there is contradiction, the definition that then provides with the application is as the criterion.
Unless otherwise indicated, all per-cent, umber, ratio etc. all are by weight herein.
The material of this paper, method and embodiment all are exemplary, and unless stated otherwise, should not be construed as restrictive.
Details are as follows in the present invention.
In specification sheets of the present invention and/or claims, " electrical condenser " refers to the storage electric charge that is made of two electrodes and therebetween dielectric materials and the device of electric energy.Electrical condenser is the main element that forms electronic circuit, often referred to as electric capacity, is widely used in the aspects such as stopping direct current, decoupling, bypass, filtering, resonant tank, energy transformation, pilot circuit.
At Power capacitor industry, electroconductive binder (conductive resin) the various element that are used to bond for example are used for the anode that applies is received lead frame.For the conductive resin that is used for this purpose, bond properties, electroconductibility and reliability are the performances of three keys.
Except the performance of these three keys, another important consideration aspect is exactly cost.In solid capacitor, take solid tantalum electrolytic capacitor as example, tantalum piece shared ratio in cost is the highest, has in addition just counted the cost height of electroconductive binder and electrically conducting coating.Yet because the metal price of the irreplaceable single formation of tantalum piece and international uniform, the cost that reduces the tantalum piece is difficult.Therefore, the effort of reduction tantalum capacitor concentrates on electrically conducting coating and the electroconductive binder more.
With regard to the cost that reduces tackiness agent, multiple choices are arranged again.Such as, using cheaply, conductive filler material replaces traditional silver-colored conductive agent.These cheaply filler comprise the particle (for example silver-colored copper-clad, silver-colored alclad, silver bag mica, silver bag glass, silver bag boron nitride etc.) of graphite, silver parcel.The price of these conductive filler materials is 10%-80% of silver-colored valency.For another example, can reduce the density of tackiness agent, because the consumption of tackiness agent is by volume.
In addition, consider that electrical condenser may be used in the various complex environments, the electroconductive binder that is used for electric capacity also must satisfy the reliability requirement that comprises hydrothermal stability.
For the many disadvantages of existing conductive resin existence and based on the consideration to above-mentioned various factors, the contriver has prepared the electroconductive binder that comprises nonmetal silver-plated particle.
Compare as conductive filler material with using fine silver, using nonmetal silver-plated particle to replace a significant advantage of silver is exactly that cost reduces greatly.
To use silver bag boron nitride particle and Yin Bao glass particle as example, they are cheap more a lot of than fine silver.In present silver-colored valency 29 $/Toz, the cost of fine silver conductive filler material the chances are 1000 $/kg so; And the price of silver bag boron nitride is about 750-800 $/kg, than fine silver conductive filler material cheap 20-25%; The price of silver bag glass is about 500 $/kg, than fine silver conductive filler material cheap 50%.
The density of silver bag boron nitride and Yin Bao glass is relatively lowly (usually to be about 3~5g/cm 3, typically for silver bag boron nitride 30-103, described density is 3.92g/cm 3), the density of silver powder/silver strip then is about 10-11g/cm 3For typical silver-colored tackiness agent, its density is at 3.2g/cm 3To 3.6g/cm 3Between; Use the density of the tackiness agent of silver bag boron nitride and Yin Bao glass then to be usually less than 2.8g/cm 3
Although with regard to performance, especially with regard to electroconductibility, silver bag boron nitride and Yin Bao glass is not as fine silver, can unexpectedly reach peer-level yet the inventor finds the conductivity of the tackiness agent that finally makes.For example, the typical volume specific resistance that is used for the argentiferous tackiness agent of tantalum capacitor is about 0.001ohmcm; The typical volume specific resistance of the tackiness agent of argentiferous bag boron nitride and Yin Bao glass then is about 0.001~0.01ohmcm, meet fully requirement to the electrical condenser tackiness agent (<0.1ohmcm).
Boron nitride and glass have chemistry and physical stability and the thermo-tolerance of superelevation.This has given silver-colored bag boron nitride and the high stability of Yin Bao glass filler, if silver must be got well in the filler particles surface-coated.
The inventor finds by test, in reliability testing, uses the tackiness agent of described conductive filler material and the tackiness agent that contains the fine silver filler unexpectedly to have same stability.
For different application requiring, the invention provides the electroconductive binder that uses the different resin system of two classes: Resins, epoxy conduction tackiness agent and bismaleimides-acrylate electroconductive binder.
Resins, epoxy conduction tackiness agent
According to one embodiment of the invention, a kind of Resins, epoxy conduction tackiness agent is provided, it comprises: the Resins, epoxy of 10~60 % by weight; 0.5 the epoxy curing agent of~6 % by weight; The silver powder particles of 0~60 % by weight; Nonmetal silver-plated particle with 15~50 % by weight.
Resins, epoxy conduction tackiness agent characteristics are that adhesiveproperties is good, and the resin cost is low.
In content of the present invention, " Resins, epoxy " refers to contain in the molecular structure macromolecular compound of epoxide group.Resins, epoxy after the curing has good physical and chemical performance, and it has excellent bonding strength to the surface of metal and non-metallic material, and hardness is high, and snappiness is better, to alkali and most of solvent-stable.Be applicable to Resins, epoxy of the present invention and comprise aromatic series glycidyl epoxy resin or aliphatic epoxy resin, for example bisphenol type or phenol aldehyde type epoxy resin.Exemplary suitable Resins, epoxy for example can be the Resins, epoxy of bisphenol A-type, the Resins, epoxy of bisphenol S type, the Resins, epoxy of Bisphenol F type, the Resins, epoxy of phenol-novolak type, the Resins, epoxy of cresols-novolak type.
In Resins, epoxy conduction tackiness agent of the present invention, can use bisphenol A type epoxy resin, for example can use the Ink available from DIC Dainippon; The Epiclon 850S of Chemicals; Available from Japan Epoxy Resins Co., the jER 828US of Ltd.Also can use the RAS-1 of Henkel Corp. (Henkel corporate).
Epoxy curing agent has another name called stiffening agent, is material or the mixture of class enhancement or gate ring epoxy resins curing reaction.Epoxy curing agent and Resins, epoxy generation chemical reaction form netted space polymer.Being applicable to solidifying agent of the present invention can be imidazole curing agent or acid anhydride type curing agent, such as dodecenylsuccinic acid acid anhydride, methylhexahydrophthalic anhydride, 1-cyanoethyl-2-ethyl-4-methylimidazole etc.
" nonmetal silver-plated particle " among the present invention refers to that the surface at the particle of non-metallic material formation is coated with the structure of silver.
In principle, the non-metallic material in the nonmetal silver-plated particle of the present invention are had no particular limits, as long as these materials can stable existence in electroconductive binder and under the Working environment of electrical condenser.For example, can use and be selected from glass, boron nitride, calcium carbonate, carbon black, carbon fiber, aluminum oxide and the polymer materials one or more.
Silver can be coated to by routine techniques means such as plating, sprayings the surface of non-metallic particle.
The density of the nonmetal silver-plated particle preferably global density with electroconductive binder is close, to avoid rotten by the floating of particle or tackiness agent that sedimentation was caused and to lose efficacy.Particularly, the density of preferred nonmetal silver-plated particle is 3~5g/cm 3
As the conductive filler material that is used for electroconductive binder, the particle diameter of nonmetal silver-plated particle is the smaller the better in principle.This is because particle diameter is less, and particle is just more difficult, and sedimentation occurs in tackiness agent, and less packing material size also helps to obtain more smooth and smooth coating.But particle diameter is less, the needed silver-plated amount in coatedparticles surface higher, and preparation technology is also more complicated, so cost also can correspondingly increase.The median size that is preferred for nonmetal silver-plated particle of the present invention is 5~100 microns, more preferably 10~40 microns, and preferred 10~20 microns again.
Generally speaking, the silver-plated amount of nonmetal silver-plated particle is more high better, but the too high cost that can cause undoubtedly of silver-plated amount is high.Simultaneously, too high silver-plated amount meeting is easy to sedimentation so that nonmetal silver-plated pellet density is too large.Consider various factors, the silver-plated amount that is preferred for nonmetal silver-plated particle of the present invention is 20~60 % by weight, for silver bag glass, more preferably 35~40 % by weight, for silver bag boron nitride, more preferably 45~55 % by weight, this silver-plated amount refer to that the quality of silver accounts for the ratio of nonmetal silver-plated particle total mass.
Consider with electroconductive binder in the consistency of other component and suitable density of material, preferably silver is wrapped glass particle or silver bag boron nitride particle is used for electroconductive binder of the present invention as conductive additive.
Silver bag boron nitride particle for example can be the silver bag boron nitride 30-103 available from Technic Inc.
Compare silver bag boron nitride particle, silver bag glass particle has more cost advantage.But, when using silver bag glass particle, tend to undesirable metal ion is brought in the electroconductive binder.When being used for the more sensitive application of foreign metal ion ratio, preferably in electroconductive binder, add ion-exchanger.Concrete ion-exchanger for example can be available from Toagosei Co., IXE 100 or the IXE770F of Ltd.
In electroconductive binder of the present invention, the content of Resins, epoxy is 10~60 % by weight.
For different Resins, epoxy types, the consumption of solidifying agent is different.Generally, the consumption of epoxy curing agent is 0.5~6 % by weight.
The consumption of silver powder is 0~60 % by weight.
The consumption of nonmetal silver-plated particle is 15~50 % by weight.
Except above-mentioned main ingredient, in binder composition of the present invention, also can add as required additive, such as adhesion promoters, dispersion agent, thixotroping conditioning agent etc.Can use the type siloxane adhesion promoters of active function groups end-blocking, such as Silane A-187, Z-6040 etc. as adhesion promoters.Can use silicone based dispersion agent as dispersion agent, for example BYK W940, BYK-333.Can use aerosil as the thixotroping conditioning agent, for example TS720, R202.
Resins, epoxy conduction tackiness agent of the present invention can be according to method preparation well known to those skilled in the art.As example, can adopt following steps to prepare Resins, epoxy conduction tackiness agent of the present invention: the first step is dissolved in solid conduction promotor in the Resins, epoxy under 60 ℃ of conditions; Second step adds solidifying agent, and hand operated mixing is even; In the 3rd step, add silver bag boron nitride (silver bag glass) and silver powder, mechanical stirring 30 minutes, 3000 rev/mins of rotating speeds.
Resins, epoxy conduction tackiness agent of the present invention can adopt this area coating means commonly used such as printing, some glue to be coated on the surface to be bonded, then baking and curing under suitable temp and humidity condition.
For Resins, epoxy conduction tackiness agent, the condition of baking and curing can be curing oven: 150 ℃-200 ℃ isothermal curing 30-60 minute (can select suitable solidification value and set time according to used solidifying agent kind); Also can adopt fast setting, under comparatively high temps, solidify 10-30 second under (250 ℃-300 ℃) condition.
The Vinylite electroconductive binder
According to another embodiment of the invention, a kind of Vinylite electroconductive binder also is provided, it comprises: the Vinylite of 10~40 % by weight; The peroxide initiator of 0~2 % by weight; The silver powder particles of 0~60 % by weight; Nonmetal silver-plated particle with 15~50 % by weight.
Vinylite electroconductive binder water resistance is good, and is strong to some metal substrate reactive force, can realize fast setting at lesser temps, is the electronic pastes stick resin system that consumption is only second to Resins, epoxy.
In content of the present invention, " Vinylite " is such resinoid, contain vinyl (carbon-carbon double bond) in its molecular structure, can issue in the initiation of superoxide or azo compound living radical polymerization, and oligomer or the superpolymer (can contain residual vinyl, as the intermediate of further grafting) of thus radical polymerization generation.This resinoid can be vinylformic acid (ester) resin, (gathering) butadiene resin, also can be to contain the group aliphatic resin that encircles double bond structure, perhaps contains the polyimide based resin of heterocycle double bond structure etc.Bimaleimide resin 24-405A such as Henkel Corp. (Henkel corporate); The polybutadiene-modified Ricon 131MA10 resin of U.S. Sartamer company; Acrylate resin SR248, SR423A resin etc.
As for nonmetal silver-plated particle, above the description of nonmetal silver-plated particle in the Resins, epoxy conduction tackiness agent is equally applicable to the Vinylite electroconductive binder, do not repeat them here.
In Vinylite electroconductive binder of the present invention, the content of Vinylite is 10~40 % by weight.
In Vinylite electroconductive binder of the present invention, the consumption of nonmetal silver-plated particle is 15~50 % by weight.
Except above-mentioned main ingredient, in thermoplastic conductive binder composition of the present invention, also can add as required additive, such as adhesion promoters, dispersion agent, thixotroping conditioning agent etc.Can use the type siloxane adhesion promoters of active function groups end-blocking, such as Silane A-187, Z-6040 etc. as adhesion promoters.Can use silicone based dispersion agent as dispersion agent, for example BYK W940, BYK-333.Can use aerosil as the thixotroping conditioning agent, for example TS720, R202.
Thermoplastic conductive tackiness agent of the present invention can be according to method preparation well known to those skilled in the art.As example, can adopt following steps to prepare thermoplastic conductive tackiness agent of the present invention: the first step is even with different types of Vinylite hand operated mixing; Second step adds solidifying agent, additive etc., and then hand operated mixing 1 minute is crossed triple-roller mill solid matter is distributed in the system; In the 3rd step, add silver bag boron nitride (silver bag glass) and silver powder, mechanical stirring 30 minutes, 3000 rev/mins of rotating speeds.
Vinylite electroconductive binder of the present invention can adopt this area coating means commonly used such as printing, some glue to be coated on the surface to be bonded, then baking and curing under suitable temp and humidity condition.
For the Vinylite electroconductive binder, the condition of baking and curing can for: curing oven: 100-175 ℃, constant temperature 1-60 minute (selecting suitable temperature and time according to the kind of solidifying agent).Fast setting: 100-280 ℃, constant temperature 10 seconds-1 minute.
Electrical condenser
The kind of electrical condenser has a lot, and is common such as ceramic condenser, aluminium electrolutic capacitor, mica capacitor, paper condenser, tantalum electrolytic capacitor, film capacitor etc. are arranged.The structure of different electrical condensers is not quite similar again, but they have a common ground, namely all is to accompany insulating material (medium) between two electrodes.
Electroconductive binder of the present invention can be used for any electrical condenser that male or female need to be bonded on the substrate, especially higher to the stability requirement under hygrothermal environment electrical condenser.Electroconductive binder of the present invention is particularly suitable for aluminium electrolutic capacitor, tantalum electrolytic capacitor or niobium electrolytic capacitor.
Take solid tantalum electrolytic capacitor as example, it comprises the conductive layer on sintered compact that tantalum briquetting sintering obtains, tantalum oxide film, manganese dioxide layer and the manganese dioxide layer that the sintered compact surface forms.
Electroconductive binder of the present invention can be used in the electrical condenser, is used for the element of bonding electrical condenser.Not only firm by the bonding that electroconductive binder of the present invention forms, have excellent electroconductibility, and also quite reliable, especially have excellent hydrothermal stability.
Embodiment
The following examples and effect data are beneficial effects that how to implement and of the present invention in order to specify the present invention, but protection scope of the present invention is not limited to these specific embodiments.
Experiment material
JER 828US: bisphenol A type epoxy resin, available from Japan Epoxy Resins Co., Ltd.
SG15F35: silver bag glass flake, silver content 35 % by weight, median size 15 μ m are available from Potter Industries Inc..
SG05TF40: silver bag glass flake, silver content 40 % by weight, median size 5 μ m are available from Potter Industries Inc..
30-103: silver bag boron nitride thin slice, silver content 53 % by weight, median size 12 μ m are available from Technic Inc..
24-405A: fatty alkane modified bismaleimide, available from Henkel corporate.
SR423A: isobornyl methacrylate, available from sartomer.
SR248: neopentyl glycol dimethacrylate, available from sartomer.
Ricon 131MA10:2, the oligomer of 5-furandione and 1,3-butadiene is available from sartomer.
Perkadox 16: two (4-tert-butylcyclohexyl) peroxy dicarbonate, and available from Akzo Nobel.
Perkadox CH-50: benzoyl peroxide, available from Akzo Nobel.
IXE770F: aluminium Mn oxide (ion-exchanger), available from Toagosei.
EA 101: silver powder, and available from Metalor Technologies
GA 23825: silver powder, and available from Metalor Technologies
Epiclon 850S: bisphenol A epoxide resin, available from DIC Dainippon Ink ﹠amp; Chemicals.
RAS-1:2,6-diepoxy propyl group-Racemic glycidol phenol is available from Henkel corporate.
SP3006:1, the 4-butanediol diglycidyl ether is available from Henkel corporate.
Ajicure PN-H: the affixture of Resins, epoxy and imidazoles, available from Ajinomoto co.Ltd.;
EMI 24Cn:1-cyanoethyl-2-ethyl-4-methylimidazole is available from PCI Synthesis.
A-187:3-(2,3-epoxy the third oxygen) propyl trimethoxy silicane is available from Momentive Performance Materials.
SPAA9829: the flake silver powder particle, available from Metalor.
DDSA:2-laurylene base-Succinic anhydried is available from Krahn co, Ltd.;
MHHPA: methylhexahydrophthalic anhydride, Dixie Chemical.
Testing method
In order to verify the excellent effect of electroconductive binder, it conducting performance test, bonding strength test, a series of tests such as density measurement and humid heat test have been carried out.
<density measurement 〉
According to industry standard ATM-0001 the conductive resin that makes is carried out density measurement, concrete test detail is as follows:
Testing used major equipment is densometer;
Then the empty densitometric quality of elder generation's weighing fills with pure water, again weighs, and draws pure water quality m1.Then empty moisture, inject conductive resin sample to be measured, draw sample quality m2.By formula D=m2/m1 * 1.0 (g/cm 3), draw the conductive resin sample rate.
<humid heat test 〉
In the following manner the conductive resin after solidifying is carried out humid heat test:
At first sample is placed relative humidity be 85% and temperature be 85 ℃ thermostat container, then whenever take out at regular intervals its volume specific resistance of sample measurement.Record by a plurality of data points can working sample at the changing conditions of for some time internal volume resistivity, the thus wet-hot aging performance of assess sample.
<volume specific resistance test 〉
Carry out conducting performance test according to the conductive resin of industry standard ATM-0020 after to dry solidification, concrete test detail is as follows:
Testing tool: the accurate digital electric bridge of Gen Rad 1689RLC;
Prepare testing sample in glass slide, coated with conductive glue forms rectangular-shaped glue-line, and length and width are about respectively 7.5 and 1.25 centimetres.Highly decide on sample, need to measure specially, generally highly be 0.001~0.01 centimetre.Glue-line is cured, then places measuring resistance on the electric bridge, according to following formula volume calculated resistivity:
ρ=0.254R/L
ρ is volume specific resistance in the formula, and R is institute's measuring resistance value, and L is height of specimen.
<bonding strength test 〉
Carry out the bonding strength test according to the conductive adhesive layer of industry standard ATM-0052 after to dry solidification, concrete test detail is as follows:
Testing tool; Dage 4000 shear strength testers;
Put a certain amount of conductive resin at the money base plate, capacitor anode is attached on this glue point, the light pressure makes glue-line cover whole electrical condenser lower surface.The conductive resin consumption is as the criterion just to be paved with the electrical condenser lower surface.Glue-line is cured, and in the lateral shear intensity of Dage 4000 instruments measurement glue-line, this intensity can be used for characterizing the bonding strength of glue-line.
Embodiment 1
The first step, with 9.68 gram bimaleimide resin 24-405A, 4.84 gram acrylate thinner SR423A, about 1 minute of 3.23 gram acrylate thinner SR248 and 9.68 gram origoester acrylate Ricon 131MA10 hand operated mixing in the 100ml container mix; Second step, in the above-mentioned solution that mixes, add 0.03 gram inhibitor Resorcinol, 0.65 gramion exchanger IXE770F, 0.77 two (4-tert-butylcyclohexyl) peroxy dicarbonates of gram initiator and the another kind of initiator benzoyl peroxide of 0.08 gram, hand operated mixing 1 minute, then cross three barrelling devices solid matter is distributed in the system, obtain the resin-curing agent part of homogeneous; The 3rd step added 29.08 Ke Yinbao boron nitride 30-103 and 41.98 gram silver powder EA101 in above-mentioned resin-curative systems, transfer in the rotation mixed instrument, stirred 30 minutes with 3000 rev/mins speed, namely got the finished product.
Change the prescription of electroconductive binder, with the electroconductive binder of the mode Preparation Example 2-9 identical with embodiment 1.
The concrete prescription of the electroconductive binder of embodiment 1-9 is as shown in table 1.
Figure BSA00000540953300121
For the ease of comparing, the below has provided fine silver glue and has used silver-colored copper-clad as the example of the electroconductive binder of conductive filler material.
Comparative examples 26: fine silver glue
Figure BSA00000540953300131
Comparative examples 27: use silver-colored copper-clad particle as the electroconductive binder of conductive filler material
Figure BSA00000540953300132
Figure BSA00000540953300141
Embodiment 10
The first step is added to 1.55 gram solid oxines among the 19.62 gram liquid epoxies Epiclon850S, is heated to 60 ℃, and mechanical stirring (3000 rev/mins) 10 minutes is all dissolved solid; Second step adds 5.16 gram thinner SP3006 in above-mentioned Resins, epoxy, 0.21 gram adhesion promoters A187 and 0.52 gram solidifying agent EMI24CN, and even 1 minute of hand operated mixing obtains uniform solution; The 3rd step added the another kind of solidifying agent Ajicure PN-H of 2.58 grams, and 25.82 Ke Yinbao boron nitride 30-103 and 44.54 gram silver powder EA101 transfer in the impeller, stir 30 minutes with 3000 rev/mins speed, namely get the finished product.
Change the prescription of electroconductive binder, with the electroconductive binder of the mode Preparation Example 11-25 identical with embodiment 10.
The concrete prescription of the electroconductive binder of embodiment 10-25 is as shown in table 2-3.
Figure BSA00000540953300151
Figure BSA00000540953300161
Shearing resistance measuring result and the warm and humid experimental measurement result of embodiment 1-25 and comparative examples 26-27 have been provided in following table 4 and the table 5.
Figure BSA00000540953300191
Figure BSA00000540953300201
Above-mentioned experimental data shows that electroconductive binder of the present invention not only possesses excellent adhesiveproperties and electroconductibility, and its hydrothermal stability is also fairly good.With regard to electroconductibility, the electroconductibility of electroconductive binder of the present invention even can compare favourably with elargol (comparative examples 26).With regard to hydrothermal stability, electroconductive binder of the present invention is better than the silver-colored copper-clad particle of use greatly as the electroconductive binder (comparative examples 27) of conductive filler material.
In present specification, in conjunction with specific embodiments the present invention is described in detail, but to those skilled in the art, obviously can in the situation that does not break away from essence of the present invention, makes various changes and modifications it.All this type of change and modification should be thought within the scope of claims of all falling into the application.

Claims (19)

1. electroconductive binder that is used for electrical condenser, it comprises:
The Resins, epoxy of 10~60 % by weight;
0.5 the epoxy curing agent of~6 % by weight;
The silver powder particles of 0~60 % by weight; With
The nonmetal silver-plated particle of 15~50 % by weight.
2. the electroconductive binder that is used for electrical condenser of claim 1, wherein said Resins, epoxy is bisphenol type or phenol aldehyde type epoxy resin.
3. the electroconductive binder that is used for electrical condenser of claim 2, wherein said Resins, epoxy is bisphenol A type epoxy resin.
4. each the electroconductive binder that is used for electrical condenser of claim 1-3, wherein said solidifying agent is selected from amine curing agent, imidazole curing agent and acid anhydride type curing agent.
5. the electroconductive binder that is used for electrical condenser of claim 4, wherein said solidifying agent is selected from imidazole curing agent and acid anhydride type curing agent.
6. each the electroconductive binder that is used for electrical condenser of claim 1-5, wherein said nonmetal silver-plated particle satisfies following at least a condition:
Density is 3~5g/cm 3,
Median size is 5~100 microns, and
Silver-plated amount is 20~60 % by weight, and this silver-plated amount refers to that the quality of silver accounts for the ratio of nonmetal silver-plated particle total mass.
7. each the electroconductive binder that is used for electrical condenser of claim 1-6, the non-metallic material in the wherein said nonmetal silver-plated particle are selected from one or more in glass, boron nitride, calcium carbonate, carbon black, carbon fiber, aluminum oxide and the polymer materials.
8. the electroconductive binder that is used for electrical condenser of claim 7, wherein said nonmetal silver-plated particle be that silver bag glass particle or silver wrap boron nitride particle.
9. the electroconductive binder that is used for electrical condenser of claim 8, wherein said nonmetal silver-plated particle be that silver wraps boron nitride particle.
10. each the electroconductive binder that is used for electrical condenser of claim 1-9, it also comprises in the following additive one or more: adhesion promoters, dispersion agent, defoamer, thixotroping conditioning agent.
11. an electroconductive binder that is used for electrical condenser, it comprises:
The Vinylite of 10~40 % by weight;
The peroxide initiator of 0~2 % by weight;
The silver powder particles of 0~60 % by weight; With
The nonmetal silver-plated particle of 15~50 % by weight.
12. the electroconductive binder that is used for electrical condenser of claim 13, wherein said Vinylite is selected from bimaleimide resin, acrylate resin, acrylic resin and butadiene resin.
13. the electroconductive binder that is used for electrical condenser of claim 13 or 14, wherein said nonmetal silver-plated particle satisfy following at least one condition:
Density is 3~5g/cm 3,
Median size is 5~100 microns, and
Silver-plated amount is 20~60 % by weight, and this silver-plated amount refers to that the quality of silver accounts for the ratio of nonmetal silver-plated particle total mass.
14. each the electroconductive binder that is used for electrical condenser of claim 13-15, the non-metallic material in the wherein said nonmetal silver-plated particle are selected from one or more in glass, boron nitride, calcium carbonate, carbon black, carbon fiber, aluminum oxide and the polymer materials.
15. the electroconductive binder that is used for electrical condenser of claim 16, wherein said nonmetal silver-plated particle are silver bag glass particle or silver bag boron nitride particle.
16. the electroconductive binder that is used for electrical condenser of claim 17, wherein said nonmetal silver-plated particle are silver bag boron nitride particle.
17. each the electroconductive binder that is used for electrical condenser of claim 13-18 wherein also comprises in the following additive one or more: adhesion promoters, dispersion agent, defoamer, thixotroping conditioning agent.
18. an electrical condenser has wherein used arbitrary described electroconductive binder among the claim 1-19.
19. the described electrical condenser of claim 20, it is aluminium electrolutic capacitor, tantalum electrolytic capacitor or niobium electrolytic capacitor.
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