JP6259270B2 - Thermosetting conductive paste composition - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a thermosetting conductive paste composition, and in particular, a coating film having excellent adhesion and conductivity by applying or printing on a substrate such as a film, a substrate, and an electronic component, and heat curing. It is related with the thermosetting conductive paste composition which can form.

  2. Description of the Related Art Conventionally, a method using a thermosetting conductive paste is widely known as one of methods for forming electrodes or electric wiring (wiring) on a substrate such as a film, a substrate, or an electronic component. In this method, when the conductor pattern is formed at a relatively low temperature, a thermosetting type containing a conductive metal powder (conductive powder) and a thermosetting resin is used. Then, the thermosetting conductive paste composition is applied or printed on the base material with a predetermined conductor pattern, and then heating is performed to dry and cure the conductor pattern on the base material. Conductor pattern electrodes, wiring, and the like are formed on the substrate.

  In the thermosetting conductive paste composition, an epoxy resin, a blocked polyisocyanate compound or the like is used as the thermosetting resin, and silver is mainly used as the conductive powder.

  For example, Patent Document 1 discloses a thermosetting conductive paste composition containing silver powder, a blocked polyisocyanate compound, an epoxy resin, and a curing agent.

  On the other hand, since silver is expensive, the development of thermosetting conductive pastes using less expensive copper, copper alloys, silver-coated copper or copper-coated copper alloys coated with silver, etc. as conductive powder In Patent Documents 2 and 3, silver-copper composite powder obtained by mechanically forcibly joining silver powder and copper powder is dispersed in a synthetic resin / solvent as an inexpensive material equivalent to silver powder. A conductive paint is disclosed.

JP 2002-161123 A JP 56-155259 A Japanese Patent Publication No. 60-017392

  The present inventors replaced the silver powder in the thermosetting conductive paste composition disclosed in Patent Document 1 with the thermosetting conductivity using silver-copper composite powder as disclosed in Patent Documents 2 and 3. As a conductive paste, a block-coated polyisocyanate compound or a blocked polyisocyanate compound and an epoxy resin are used as a thermosetting resin, and copper, a copper alloy, silver-coated copper in which copper is coated with silver, or a copper alloy as a conductive powder Development of a thermosetting conductive paste using coated copper alloy coated with silver was investigated.

  However, compared with the case where only silver is used as the conductive powder, there is a problem that the viscosity increases with time due to the storage of the thermosetting conductive paste, and the conductivity decreases.

  The present invention has been made in order to solve such problems, and provides a thermosetting conductive paste composition having excellent storage stability by preventing increase in viscosity and decrease in conductivity due to storage. The purpose is to do.

  In order to solve the above problems, the thermosetting conductive paste composition according to the present invention has (A) conductive powder, (B) thermosetting resin, (C) curing agent, and (D) inorganic. An ion exchanger, and (A) at least one selected from the group consisting of copper, a copper alloy, silver-coated copper, and a silver-coated copper alloy is used as the conductive powder, and (B) a thermosetting resin As a structure containing a blocked polyisocyanate compound or a blocked polyisocyanate compound and an epoxy resin.

  In the above-described configuration, the (D) inorganic ion exchanger may contain any one of zirconium, magnesium, aluminum, silicon, antimony, and bismuth as a main component.

  Moreover, in the said structure, 0.01-3 mass% may be sufficient with respect to said (A) electroconductive powder content of the said (D) inorganic ion exchanger.

  And in the said structure, as said (A) electroconductive powder, at least 1 sort (s) selected from the group which consists of copper, a copper alloy, silver coat copper, and a silver coat copper alloy, and silver, copper, a copper alloy, The compounding ratio of at least one selected from the group consisting of silver-coated copper and silver-coated copper alloy and silver may be 100: 0 to 1:99 (excluding 100: 0) by mass ratio.

  Furthermore, in the said structure, you may further contain at least 1 sort (s) selected from the group which consists of gold | metal | money, palladium, nickel, aluminum, lead, and carbon as said (A) electroconductive powder.

  In the present invention, with the above configuration, even when copper, copper alloy, silver-coated copper, and silver-coated copper alloy are used as the conductive powder, the increase in viscosity due to storage and the decrease in conductivity are prevented, and excellent storage stability is achieved. The thermosetting conductive paste composition having the property can be provided.

It is a top view which shows the shape of the conductive pattern for evaluating the characteristic (conductor resistance) of the thermosetting conductive paste composition which concerns on this invention.

  Hereinafter, an example of a preferred embodiment of the present invention will be specifically described.

[(A) Conductive powder]
The conductive powder (A) in the thermosetting conductive paste composition according to the present invention uses at least one selected from the group consisting of copper, copper alloy, silver-coated copper, and silver-coated copper alloy. However, these specific blending species and blending ratios thereof are not particularly limited, and according to the present invention, an increase in viscosity due to storage and a decrease in conductivity can be prevented, and excellent storage stability can be realized.

  The copper alloy in the present invention is an alloy mainly composed of copper and added with various elements (silver, zinc, nickel, cobalt, tin, lead, aluminum, chromium, cadmium, beryllium, tellurium, etc.). The silver-coated copper alloy is a particle in which the surface of copper or a copper alloy particle is coated with silver by a reduction plating coating method, a displacement plating coating method, or the like.

  Moreover, having copper as a main component means an alloy containing 50% by mass or more of copper.

  (A) In addition to at least one selected from the group consisting of copper, copper alloys, silver-coated copper, and silver-coated copper alloys, the conductive powder may contain silver.

  In this case, the compounding ratio of at least one selected from the group consisting of copper, copper alloy, silver-coated copper, and silver-coated copper alloy and silver is 100: 0 to 1:99 (100: 0). Excluding)).

  Further, (A) the conductive powder may further contain at least one selected from the group consisting of gold, palladium, nickel, aluminum, lead and carbon.

  In the present invention, it is preferable that the upper limit of the amount of alkali metal ions contained in (A) the conductive powder is determined. Specifically, the amount of sodium ions and potassium ions contained in the conductive powder (A) is preferably less than 200 ppm, more preferably less than 100 ppm, and even more preferably less than 10 ppm. In the present invention, it is preferable that at least the amount of sodium ions is less than 200 ppm. If the amount of these ions exceeds 200 ppm, problems are likely to occur in the electrical characteristics and reliability of an electronic component or electronic device in which electrodes and wirings are formed with a thermosetting conductive paste. On the other hand, the lower the lower limit of these ions, the better.

  The conductive powder (A) in the thermosetting conductive paste composition according to the present invention uses at least one selected from the group consisting of copper, copper alloy, silver-coated copper, and silver-coated copper alloy. However, flake powder and spherical powder can be used for the shape of these (A) conductive powders.

  The flaky powder in the present invention may be a powder having a shape close to a flat plate or a thin rectangular parallelepiped when viewed as a whole, even if there is unevenness and deformation is seen partially. In addition, flake shape can be paraphrased as flake shape or scale shape. In addition, the spherical powder in the present invention may be a three-dimensional powder that is closer to a cube than a rectangular parallelepiped when viewed as a whole, even if there are irregularities and deformation is observed. Note that the spherical shape can be restated as granular.

Of the conductive powder in the present invention, a preferred configuration of the flaky powder will be specifically described. The average particle diameter D50 of the flaky powder is preferably in the range of 2 to 20 μm, the BET specific surface area is preferably in the range of 0.1 to ¹ m ² / g, and the tap density is 3 to 7 g / cm. It is preferable to be within the range of ³ , and the aspect ratio is preferably within the range of 5 to 15.

  More specifically, the average particle diameter D50 of the flaky powder is preferably in the range of 2 to 20 μm as described above, more preferably in the range of 2 to 12 μm, and in the range of 6 to 10 μm. Further preferred. If the average particle diameter D50 of the flaky powder is smaller than 2 μm, the contact resistance between the conductive powders tends to increase, and sufficient conductivity may not be obtained. On the other hand, if the average particle diameter D50 is larger than 20 μm, the contact resistance between the conductive powders becomes small. However, when a conductor pattern is printed using a mesh screen, the mesh screen is clogged or fine wiring is formed. It may be difficult.

The BET specific surface area of the flaky powder is preferably in the range of 0.1 to ¹ m ² / g as described above, but more preferably in the range of 0.2 to 0.8 m ² / g. More preferably, it is in the range of ^{2 to} 0.5 m ² / g. If the BET specific surface area of the flaky powder is smaller than 0.1 m ² / g, the flake thickness becomes too thick and the shape of the flaky powder becomes nearly spherical, so the contact area between the conductive powders tends to be small. Sufficient conductivity may be obtained. On the other hand, if the BET specific surface area exceeds 1 m ² / g, the contact area between the conductive powders becomes large, but the paste viscosity becomes high, so that high filling becomes difficult (that is, in the conductive paste composition). There is a tendency that it is difficult to improve the content of the conductive powder), so that sufficient conductivity may not be obtained.

The tap density of the flaky powder is preferably in the range of ^{3 to} 7 g / cm ³ as described above, more preferably in the range of ^{3 to} 6 g / cm ³ , and 3.5 to 5.5 g / cm. If it is in the range of ³ , it is more preferable. If the tap density of the flaky powder is less than 3 g / cm ³ , the flaky powder tends to be bulky and high filling tends to be difficult, so that sufficient conductivity may not be obtained. On the other hand, if the tap density exceeds 7 g / cm ³ , it is usually difficult to industrially produce the flaky powder.

  The aspect ratio of the flaky powder is preferably in the range of 5 to 15 as described above, more preferably in the range of 6 to 12, and further preferably in the range of 6 to 10. If the aspect ratio of the flaky powder is less than 5, flaking is insufficient and the contact area between the conductive powders tends to be small, and sufficient conductivity may not be obtained. On the other hand, if the aspect ratio exceeds 15, the contact area between the conductive powders becomes large, but it tends to be difficult to achieve high filling, so there is a possibility that sufficient conductivity cannot be obtained.

  The manufacturing method of the said flaky powder is not specifically limited, A well-known method can be used. Specifically, for example, a flaky powder can be produced by using a spherical powder (described later) produced by a known method as a base powder and subjecting the base powder to a known mechanical treatment. The physical properties such as the particle size and cohesion of the base powder are appropriately determined according to the purpose of use of the conductive paste composition (types of electrodes, wirings, etc., or types of electronic components or electronic devices equipped with these electrodes, wirings, etc.) You can choose.

Next, a preferable configuration of the spherical powder among the conductive powder (A) in the present invention will be specifically described. The average particle diameter D50 of the spherical powder is preferably in the range of 0.1 to 10 μm, the BET specific surface area is preferably in the range of 0.5 to 1.7 m ² / g, and the tap density is 1. It is preferable that it is 5-5 g / cm < ³ >, and it is preferable that the aggregation degree D50 / DSEM exists in the range of 2-15.

  More specifically, the average particle diameter D50 of the spherical powder is preferably in the range of 0.1 to 10 μm as described above, more preferably in the range of 1 to 5 μm, and in the range of 1 to 3 μm. More preferred. If the average particle diameter D50 of the spherical powder is smaller than 0.1 μm, the thermosetting conductive paste has a high viscosity, which may make it difficult to form a paste. On the other hand, if the average particle diameter D50 is larger than 10 μm, as in the case of the flaky powder, when a conductor pattern is printed using a mesh screen, the mesh screen is clogged or it is difficult to form fine wiring. There is a risk of

The BET specific surface area of the spherical powder is preferably in the range of 0.5 to 1.7 m ² / g as described above, but more preferably in the range of 0.6 to 1.6 m ² / g, 0 More preferably, it is in the range of 1.9 to 1.6 m ² / g. If the BET specific surface area of the spherical powder is smaller than 0.5 m ² / g, the contact area between the conductive powders (A) tends to be small, and sufficient conductivity may not be obtained. On the other hand, if the BET specific surface area exceeds 1.7 m ² / g, the contact area between the conductive powders (A) increases, but the paste viscosity tends to be high and high filling tends to be difficult. There is a possibility that conductivity cannot be obtained.

Moreover, the tap density of the spherical powder is in the range of as 1.5 to 5 g / cm ³ of the preferably, more preferably be within the range of 2-5 g / cm ^3, a range of 3 to 4 g / cm ³ If it is in, it is more preferable. If the tap density of the spherical powder is less than 1.5 g / cm ³ , (A) the conductive powder tends to be bulky and high filling tends to be difficult, so that sufficient conductivity may not be obtained. is there. On the other hand, if the tap density exceeds 5 g / cm ³ , the dispersibility of the spherical powder becomes too good, and the resin component tends to wrap around between the (A) conductive powders. The interface resistance tends to increase, and there is a possibility that sufficient conductivity cannot be obtained.

  Further, as described above, the aggregation degree D50 / DSEM of the spherical powder is preferably in the range of 2 to 15, more preferably in the range of 3 to 11, and further preferably in the range of 3 to 7.5. . If the degree of aggregation D50 / DSEM is less than 2, the dispersibility of the spherical powder becomes too good, and (A) the resin component tends to wrap around between the conductive powders, so (A) the interfacial resistance between the conductive powders Tends to be large, and sufficient conductivity may not be obtained. On the other hand, if the degree of aggregation D50 / DSEM is greater than 15, (A) the conductive powder tends to be bulky and high filling tends to be difficult, so that sufficient conductivity may not be obtained.

  The method for producing the spherical powder is not particularly limited, and in the present embodiment, for example, a product produced by a wet reduction method can be suitably used, but other known methods such as an electrolytic method and an atomizing method can be used. A spherical powder produced by the method can also be used.

[(B) Thermosetting resin]
As the (B) thermosetting resin used in the thermosetting conductive paste composition according to the present invention, components known in the field of the thermosetting conductive paste composition can be suitably used. Typically, (B1) an epoxy resin and (B2) a blocked polyisocyanate compound can be mentioned. In order to realize good conductor resistance, (B) thermosetting resin contains (B2) a blocked polyisocyanate compound, or (B1) contains an epoxy resin and (B2) a blocked polyisocyanate compound. It is preferable.

  (B) When these (B1) epoxy resin and (B2) blocked polyisocyanate compound are used as the thermosetting resin, these may be used after being blended at a predetermined blending ratio, as will be described later. preferable.

  (B1) Although the specific kind and structure of an epoxy resin are not specifically limited, It is preferable that all are polyvalent epoxy resins which have a 2 or more oxirane ring (epoxy group) in 1 molecule. For example, epichlorohydrin, novolak such as phenol novolak and cresol novolak, polyphenol such as bisphenol A, hydrogenated bisphenol A, bisphenol F, bisphenol AD, and resorcin, ethylene glycol, neopentyl glycol, glycerin, trimethylolpropane, pentaerythritol Glycidyl ether type obtained by reacting polyhydric alcohol such as triethylene glycol and polypropylene glycol; glycidyl amine type obtained by reacting polyamino compound such as ethylenediamine, triethylenetetramine and aniline; adipic acid Glycidyl ester type obtained by reacting with polyvalent carboxyl compounds such as phthalic acid and isophthalic acid, oxidation of olefin, etc. Alicyclic type, etc. to be can be given. These epoxy resins may be used alone or in combination.

  Further, as the (B2) blocked polyisocyanate compound, a compound known in the field of thermosetting conductive paste can be suitably used.

  Specifically, for example, aromatic isocyanates such as tolylene diisocyanate, diphenylmethane diisocyanate, polymethylene polyphenyl polyisocyanate, tolidine diisocyanate, xylylene diisocyanate, naphthalene diisocyanate; hexamethylene diisocyanate, isophorone diisocyanate, hydrogenated xylylene diisocyanate, dicyclohexyl And aliphatic polyisocyanates such as methane diisocyanate, octamethylene diisocyanate, and trimethylhexamethylene diisocyanate. These polyisocyanate compounds may be used alone or in combination of two or more. Of these polyisocyanate compounds, polymethylene polyphenyl polyisocyanates having three or more nuclei are more preferably used.

  In the present embodiment, a terminal isocyanate group-containing compound synthesized by reacting a known polyisocyanate and a known polyol by a known method can also be suitably used as the polyisocyanate compound in the present invention. The polyol used in this case is not particularly limited, and general polyether polyols, polyester polyols, polycarbonate polyols and the like can be suitably used.

  The (B2) blocked polyisocyanate compound in the present invention is obtained by blocking the polyisocyanate compound described above, but the blocking agent for the polyisocyanate compound is not particularly limited, and imidazoles, phenols, oximes, etc. Can be suitably used.

  In the thermosetting conductive paste according to the present invention, when (B1) epoxy resin and (B2) blocked polyisocyanate compound are used in combination as (B) thermosetting resin, the mixing ratio (mixing ratio) is particularly Although not limited, it is preferable to mix | blend within the range of B1: B2 = 0: 100-90: 10 (except 0: 100) by mass ratio, and mix | blended within the range of 10: 90-80: 20. More preferably.

  When the total of (B1) epoxy resin and (B2) blocked polyisocyanate compound is 100 parts by mass, if (B1) epoxy resin is 90 parts by mass or less, that is, (B2) blocked polyisocyanate compound is If it is 10 parts by mass or more, (B2) the effect of accelerating the contact between the conductive powders (A) due to curing shrinkage of the blocked polyisocyanate compound is great, and it is preferable because sufficient conductivity can be obtained.

  (B) Although content of thermosetting resin is not specifically limited, In this Embodiment, it is preferable that it exists in the range of 1-40 mass parts with respect to 100 mass parts of (A) electroconductive powder, More preferably within the range of 30 parts by mass, and even more preferably within the range of 1 to 20 parts by mass. (B) If the content of the thermosetting resin is 1 part by mass or more, the adhesion to the substrate is good, and if it is 40 parts by mass or less, it is preferable because sufficient conductivity can be obtained.

  Further, the thermosetting conductive paste according to the present invention includes (B) a thermosetting resin, (B1) an epoxy resin, and (B2) other resins known as binder resins in addition to the blocked polyisocyanate compound. It may contain. Examples of other resins that can be used as the binder resin include, but are not limited to, phenol resins, polyester resins, polyurethane resins, acrylic resins, melamine resins, polyimide resins, and silicone resins.

[(C) Curing agent]
The (C) curing agent used in the thermosetting conductive paste according to the present invention is not particularly limited as long as it is a compound that can cure the (B) thermosetting resin. In the present embodiment, (B) thermosetting resin preferably contains (B2) a blocked polyisocyanate compound, or (B1) an epoxy resin and (B2) a blocked polyisocyanate compound. The (C) curing agent is not particularly limited as long as it cures at least the (B1) epoxy resin or the (B2) blocked polyisocyanate compound. In the field of thermosetting conductive paste, Well-known various compounds can be mentioned.

  Specifically, for example, phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, maleic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, succinic anhydride Acid anhydrides such as acids; imidazole, 2-methylimidazole, 2-ethyl-4methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1-benzyl-2-methylimidazole, 2-phenyl-4methyl Imidazoles such as imidazole, 1-cyanoethyl-2-methylimidazole, 1-aminoethyl-2-methylimidazole, 1-methylimidazole, 2-ethylimidazole; dimethyloctylamine, dimethyldecylamine, dimethyllaurylamine, dimethyl Listylamine, dimethylpalmitylamine, dimethylstearylamine, dimethylbehenylamine, dilaurylmonoethylamine, methyldidecylamine, methyldioleylamine, triallylamine, triisopropanolamine, triethylamine, 3- (dibutylamino) propylamine, tri-n -Tertiary amines such as octylamine, 2,4,6-trisdimethylaminomethylphenol, triethanolamine, methyldiethanolamine, diazabicycloundecene; boron trifluoride ethyl ether, boron trifluoride phenol, three Contains boron fluoride such as boron fluoride piperidine, boron acetate trifluoride, boron trifluoride monoethylamine, boron trifluoride triethanolamine, boron trifluoride monoethanolamine Suic acid or its compounds; such as Amicure series PN-23 or MY-24 commercially available from Ajinomoto Fine Techno Co., Ltd., Fujicure series FXR-1020 or FXR-1030 commercially available from Fuji Kasei Kogyo Co., Ltd. Amine adducts; dicyandiamide; and the like. These compounds may be used alone or in combination of two or more.

  (C) Although the addition amount of a hardening | curing agent is not specifically limited, In this Embodiment, it is preferable to exist in the range of 1-30 mass parts with respect to 100 mass parts of (B) thermosetting resin, and 1-15 More preferably within the range of parts by mass, and even more preferably within the range of 1 to 10 parts by mass. (C) If the addition amount of the curing agent is less than 1 part by mass, (B) the thermosetting resin may be insufficiently cured, and the cured product (electrode, wiring, etc.) has good conductivity. May not be obtained. On the other hand, if it exceeds 30 parts by mass, the paste viscosity may be increased, and it is not preferable in terms of cost.

[(D) Inorganic ion exchanger]
The (C) inorganic ion exchanger used in the thermosetting conductive paste composition according to the present invention is not particularly limited as long as it can capture copper ions in the thermosetting conductive paste composition, but is not limited to zirconium. It is preferable that any one of magnesium, aluminum, silicon, antimony, and bismuth is a main component.
In the present invention, the main component of (D) inorganic ion exchange means that (D) 50% by mass or more of the components constituting the inorganic ion exchanger.

  Specific examples of such (D) inorganic ion exchangers include, for example, the IXEPLAS series, IXE series cation exchange or both ion exchange types (IXEPLAS A-1, A-) commercially available from Toa Gosei Co., Ltd. 2, B-1, IXE-100, 300, 600, 633, 6107, 6136, etc.), or the Kyoward series cation exchange or both ion exchange types (Kyoword 600, 700, 1000, 2000, etc.). These may use only 1 type and may use it in combination of 2 or more type as appropriate.

  In this invention, it is preferable to contain (D) an inorganic ion exchanger in the quantity of 0.01-3 mass% with respect to (A) electroconductive powder, and it contains in the quantity of 0.02-2 mass%. It is more preferable that it is contained in an amount of 0.03 to 1% by mass. (D) If the content of the inorganic ion exchanger is 0.01% by mass or more, copper ions can be sufficiently captured, and it has better storage stability, and if it is 3% by mass or less, sufficient conductivity is obtained. Is preferable.

[Production of thermosetting conductive paste composition]
The manufacturing method of the thermosetting conductive paste composition according to the present invention is not particularly limited, and a known method in the field of thermosetting conductive paste can be suitably used. As a typical example, there is a method in which the above-described components are blended at a predetermined blending ratio (mass basis) and formed into a paste using a known kneading apparatus. Examples of the kneading apparatus include a three roll mill.

  In the thermosetting conductive paste according to the present invention, each component ((A) conductive powder, (B) thermosetting resin, (C) curing agent, ( In addition to D) inorganic ion exchangers, various additives known in the field of thermosetting conductive pastes may be contained. Although it does not specifically limit as the said additive, Specifically, a dispersing agent, a leveling agent, antioxidant, a ultraviolet absorber, a silane coupling agent, an antifoamer, a viscosity modifier etc. can be mentioned, for example. These additives can be added as long as the effects of the present invention are not hindered.

Moreover, the formation method of a conductor pattern is not specifically limited by the thermosetting conductive paste composition which concerns on this invention, A well-known various method can be used suitably. Typically, as shown in the examples described later, there is a screen printing method, and particularly, it is suitably used for forming a conductor pattern by this screen printing method, but the present invention is not limited to this, and an ink jet method. It can also be applied to other printing methods such as the dispenser method and the dispenser method.
[Use of thermosetting conductive paste composition]
The thermosetting conductive paste according to the present invention can be widely used for forming high-definition electrodes and wirings. Specifically, for example, a collector electrode of a solar battery cell; an external electrode of a chip-type electronic component; an RFID (Radio Frequency IDentification), an electromagnetic wave shield, a vibrator adhesive, a membrane switch, or a component used for electroluminescence It can be suitably used for applications such as electrodes or wirings. Among these applications, one of particularly preferable applications is a collecting electrode of a solar battery cell.

  The present invention will be described more specifically based on examples, comparative examples, and reference examples, but the present invention is not limited thereto. Those skilled in the art can make various changes, modifications, and alterations without departing from the scope of the present invention. In addition, measurement / evaluation of various synthesis reactions and physical properties in the following examples were performed as follows.

(Measurement and evaluation method)
[Evaluation method of conductive powder]
(1) Average particle diameter D50
The average particle diameter D50 of the flaky powder and the spherical powder was evaluated by a laser diffraction method. A sample of 0.3 g of flaky powder or spherical powder was weighed into a 50 ml beaker, 30 ml of isopropyl alcohol was added, and then dispersed by treating with an ultrasonic cleaner (USM-1 manufactured by As One Co., Ltd.) for 5 minutes. The average particle size D50 was measured and evaluated using a track particle size distribution measuring device (Microtrack particle size distribution measuring device 9320-HRA X-100 manufactured by Nikkiso Co., Ltd.).

(2) Evaluation of BET specific surface area The BET specific surface area of flaky powder or spherical powder was evaluated by measuring 1 g of a sample using a monosorb (manufactured by Quanta Chrome) by a BET one-point method by nitrogen adsorption. In the measurement of the BET specific surface area, the deaeration conditions before the measurement were 10 minutes at 60 ° C.

(3) Evaluation of tap density The tap density of the flaky powder or spherical powder was measured using a tap density measuring device (Casa specific gravity measuring device SS-DA-2 manufactured by Shibayama Scientific Instruments Co., Ltd.) and weighing 15 g of the sample. And tapped 1,000 times with a drop of 20 mm, and evaluated by calculating the tap density according to the following equation.

Tap density = sample mass (15 g) / sample volume after tapping (cm ³ )

[Measurement of paste viscosity]
The paste viscosity of the thermosetting conductive paste composition was measured using a DV-III viscometer manufactured by Brookfield. CP-52 was used as the cone at the time of measurement, and the paste viscosity (η1 rpm) at 1 rpm rotation (shear rate 2 s-1) was measured.

[Measurement of conductor resistance]
An alumina substrate was used as the base material. As shown in FIG. 1, the thermosetting conductive paste composition of the example or comparative example is used on the surface of the alumina substrate, and terminals 11a and 11b are provided at both ends, and the wiring portion 11c has a zigzag shape. The resulting conductor pattern 11 was screen printed. Thereafter, the alumina substrate was heated in a hot air dryer at 180 ° C. for 60 minutes to cure the conductor pattern 11 (thermosetting conductive paste composition). This produced a sample for conductor resistance evaluation.

  About the sample for conductor resistance evaluation of each Example or Comparative Example, the film thickness of the conductor pattern 11 is a surface roughness meter (Surfcom 480A manufactured by Tokyo Seimitsu Co., Ltd.), and the electrical resistance is a digital multimeter (R6551 manufactured by Advantest Corporation). The conductor resistance was calculated and evaluated based on the film thickness, electrical resistance, and aspect ratio of the wiring pattern.

(Examples 1-18) (Comparative Examples 1-6) (Reference Examples 1-2)
[Method for preparing thermosetting conductive paste composition]
Using (A) conductive powder shown in Table 1, (B) thermosetting resin shown in Table 2, (C) curing agent, and (D) inorganic ion exchanger, (A) conductive powder / (B ) Thermosetting resin / (C) curing agent is blended at a mass ratio of 90/10 / 0.5, and (D) inorganic ion exchanger is shown in Table 3 with respect to (A) conductive powder. After adding and kneading with a three-roll mill at such a blending ratio, butyl diglycol acetate was added to adjust the viscosity of the paste to 100 Pa · s (1 rpm) to prepare a thermosetting conductive paste composition.

  In Table 1, the copper alloy is an alloy to which nickel and zinc are added.

  About the obtained thermosetting type conductive paste composition, the initial conductor resistance, the viscosity and the conductor resistance after storage at 30 ° C. for 3 days and after storage at 0 ° C. for 3 months were measured. The results are shown in Table 4.

  The viscosity and conductor resistance after elapse of a predetermined storage period shown in Table 4 show relative values with the viscosity and conductor resistance immediately after preparation of the thermosetting conductive paste composition being 1.0.

Comparing the results of Examples 1-18 and Comparative Examples 1-5, the viscosity and conductor resistance of Examples 1-18 are 1.0 or 1.1, and the viscosities of Comparative Examples 1-5 are both 1 .4 or more, both conductor resistance is 1.2 or more, (D) By containing an inorganic ion exchanger, (A) copper, silver-coated copper, copper alloy or silver-coated copper as conductive powder It can be seen that the thermosetting conductive paste using the alloy has small changes in viscosity and conductor resistance, and good results are obtained.

  As described above, according to the present invention, by using the inorganic ion exchanger (D), even when copper, copper alloy, silver-coated copper, and silver-coated copper alloy are used as the conductive powder, the viscosity increases due to storage. In addition, it is possible to provide a thermosetting conductive paste composition that prevents deterioration in electrical conductivity and has excellent storage stability.

  It should be noted that the present invention is not limited to the description of the above-described embodiment, and various modifications are possible within the scope shown in the scope of claims, and each disclosed in different embodiments and a plurality of modifications. Embodiments obtained by appropriately combining technical means are also included in the technical scope of the present invention.

  INDUSTRIAL APPLICABILITY The present invention can be suitably used in the field of manufacturing various electronic devices and electronic components, and in particular, collecting electrodes for solar cells, external electrodes for chip-type electronic components, RFID, electromagnetic wave shields, vibrator adhesives, membrane switches Alternatively, it can be suitably used in fields where it is required to form higher-definition electrodes and wiring such as electrodes and wiring of parts used for electroluminescence and the like.

11 Conductor pattern 11a Terminal 11b Terminal 11c Wiring part

Claims (5)

(A) conductive powder, (B) thermosetting resin, (C) a curing agent, and (D) an inorganic ion exchanger,
(A) As the conductive powder, using at least one selected from the group consisting of copper, copper alloy, silver-coated copper, and silver-coated copper alloy,
(B) A thermosetting conductive paste composition containing a blocked polyisocyanate compound or a blocked polyisocyanate compound and an epoxy resin as a thermosetting resin. The (D) inorganic ion exchanger is mainly composed of any one of zirconium, magnesium, aluminum, silicon, antimony, and bismuth,
The thermosetting conductive paste composition according to claim 1. The content of the (D) inorganic ion exchanger is 0.01 to 3% by mass with respect to the (A) conductive powder,
The thermosetting conductive paste composition according to claim 1 or 2. As the conductive powder (A), at least one selected from the group consisting of copper, copper alloy, silver-coated copper, and silver-coated copper alloy, and silver,
The compounding ratio of at least one selected from the group consisting of copper, copper alloy, silver-coated copper, and silver-coated copper alloy and silver is 100: 0 to 1:99 (excluding 100: 0) in mass ratio. It is characterized by being,
The thermosetting conductive paste composition according to any one of claims 1 to 3. The (A) conductive powder further contains at least one selected from the group consisting of gold, palladium, nickel, aluminum, lead and carbon,
The thermosetting conductive paste composition according to any one of claims 1 to 4.

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