WO2006106849A1

WO2006106849A1 - Conductive paste composition and printed wiring board

Info

Publication number: WO2006106849A1
Application number: PCT/JP2006/306709
Authority: WO
Inventors: Tsutomu Uchimi; Masayuki Nagashima; Masaru Kobayashi; Hiroyuki Shirogane; Masayuki Mori; Naomi Usuki
Original assignee: Dai Nippon Printing Co., Ltd.; The Inctec Inc.
Priority date: 2005-03-31
Filing date: 2006-03-30
Publication date: 2006-10-12
Also published as: KR20070116673A; CN101156218A; TW200701259A; JP4841158B2; CN101156218B; TWI342571B; JP2006286367A; KR100995607B1

Abstract

Disclosed is a conductive paste composition composed of a phenol resin, a melamine resin, a conductive powder, a solvent and a dihydric alcohol having an ether bond. Also disclosed is a printed wiring board characterized by using such a conductive paste composition. The conductive paste composition enables to form a coating film having a sufficient thickness by a single coating operation. By using this conductive paste composition, a bump having a sufficient height can be formed with a fewer number of coating operations than the conventional conductive paste compositions.

Description

Specification

Conductive paste composition and printed wiring board

Technical field

TECHNICAL FIELD [0001] The present invention relates to a novel conductive paste composition and a printed wiring board.

. Preferably, the present invention relates to a conductive paste composition particularly suitable for forming electrode bumps used for interlayer connection of multilayer printed wiring boards and a printed wiring board using the same.

Background art

Conventionally, conductive paste compositions have been used in many applications such as for IC circuits, conductive adhesives, and electromagnetic wave shields in the electronics field. Particularly recently, a first substrate provided with a conical conductive bump made of a conductive paste at a predetermined position on at least one surface and a second substrate provided with a wiring pattern on at least one surface are provided. A laminate in which the surface on which the conductive bumps are provided and the surface on which the wiring pattern is provided are opposed to each other, and an insulator layer is disposed between the first substrate and the second substrate. And a method of manufacturing a printed wiring board in which a conductive wiring portion is formed by penetrating the bump in the thickness direction of the insulating layer by laminating and pressing the laminated body! Speak (Japanese Patent Publication No. 6-350258).

[0003] In addition, a through-type conductive wiring portion can be formed that has good pre-predder penetrability, does not generate cracks during penetration and pressing, and has a high adhesive force between the bump after penetration and the wiring pattern. In the production of printed wiring boards having a conductive paste, a conductive paste containing melamine resin, phenol resin, epoxy resin, conductive powder and solvent is provided as a conductive paste having high yield and good connection reliability. An electrically conductive best composition for interlayer connection of printed wiring boards has been proposed in which the softening point of the epoxy resin is 80 ° C. or higher and 130 ° C. or lower (JP 2002-270033 A). ).

[0004] In addition, it is necessary to provide an adhesive paste composition for interlayer connection of printed wiring boards that can form bumps without high, hardness, cracking, and poor connection with a wiring pattern. A resin and a lead selected from either a resin or an epoxy resin It has been proposed to use an electrically conductive paste composition for interlayer connection of printed wiring boards characterized by containing an electropowder and a dihydric alcohol having a boiling point of 180 ° C or higher and / or a trivalent alcohol ( JP 2003-77337 A).

[0005] Further, according to Japanese Patent No. 3588400, as an example of providing a thermosetting conductive resin composition capable of washing an apparatus, a jig and a container with water after screen printing, a water-soluble thermosetting resin is provided. There is known a conductive resin composition characterized by containing fat, conductive particles and dihydric alcohol.

[0006] According to Japanese Patent Application Laid-Open No. 9-286924, as in Patent No. 3588400, a water-soluble thermoplastic resin, an average particle size, and the like as a conductive resin composition capable of washing a screen plate after printing with water. Conductive particles having a diameter of 0.05 to 50 m and those containing dihydric alcohol are known.

[0007] JP-A-2001-11388 discloses a multilayer capacitor electrode paste composition containing a water-soluble resin and glycol capable of washing a plate used for printing with water.

[0008] According to Japanese Patent Laid-Open No. 2003-331648 and Japanese Patent Laid-Open No. 2004-265826, as metal pastes that can be baked at low temperatures, organometallic compounds and alcohol compounds of Group 3 to Group 15 metals of the periodic table, preferably Metal pastes containing glycols are known.

Patent Document 1: Japanese Patent Laid-Open No. 6-350258

Patent Document 2: JP 2002-270033 A

Patent Document 3: Japanese Patent Laid-Open No. 2003-77337

Patent Document 4: Japanese Patent No. 3588400

Patent Document 5: Japanese Patent Laid-Open No. 9-286924

Patent Document 6: Japanese Unexamined Patent Publication No. 2001-11388

Patent Document 7: Japanese Patent Laid-Open No. 2003-331648

Patent Document 8: Japanese Patent Application Laid-Open No. 2004-265826

Disclosure of the invention

Problems to be solved by the invention

[0009] When forming electrode bumps by the method described in JP-A-6-350258, disclosed in JP-A-2002-270033 and JP-A-2003-77337. When the conductive paste composition as described above is used, the bump height sufficient to penetrate the insulating layer cannot be obtained by a single coating operation of the conductive paste composition. It was necessary to carry out the overprinting by performing the coating operation of a plurality of times. In particular, the bump height cannot be obtained because the bump shape is not excessively sharpened because the bump does not break or chip when penetrating through the insulating layer or during pressing. The number of times tended to increase.

[0010] The techniques described in Japanese Patent No. 3588400, Japanese Patent Application Laid-Open No. 9-286924 and Japanese Patent Application Laid-Open No. 2001-11388 use water-soluble resin, and Japanese Patent Application Laid-Open No. 2003-331648. The technique described in Japanese Unexamined Patent Publication No. 2004-265826 uses a fired-type metal paste, which is a water-insoluble, non-fired conductive paste composition as in the present invention, and is used once. As far as the present inventors know, no paste composition has been obtained so far that a sufficient coating thickness can be obtained by the coating operation.

Means for solving the problem

[0011] The present invention intends to provide a solution to the above problem by using a solvent mainly containing a specific compound.

[0012] Accordingly, the conductive paste composition according to the present invention is a phenolic resin, a melamine resin, a conductive powder, a solvent and a divalent alcohol having an ether bond.

[0013] Such a conductive paste composition according to the present invention includes, as a preferred embodiment, one having a divalent alcohol power having an ether bond and having an ethylenedioxy moiety in its molecular structure.

[0014] Such a conductive paste composition according to the present invention preferably includes, as an aspect, one having a hydroxyl group at both ends of the divalent alcohol having an ether bond.

In such a conductive paste composition according to the present invention, as a preferred embodiment, the divalent alcohol having an ether bond is diethylene glycol, triethylene glycol, tetraethylene dalycol, pentaethylene glycol or hexaethylene. Glycol power group power includes at least one selected. [0016] Such a conductive paste composition according to the present invention preferably has, as an embodiment, when the total of the solvent and the divalent alcohol having an ether bond is 100% by mass, the divalent having the ether bond. which alcohol contains from 0.1 to 50 weight ^_0/0, encompass.

[0017] In such a conductive paste composition according to the present invention, as a preferred embodiment, the solvent is selected from the group consisting of butinorecanorebitonoreacetate, ethinore acetate, butinore acetate, ethinorecerosonolev, butylacetosolve, Including those containing at least one selected from the group consisting of til carbitol, butyl carbitol, isopropanol, butanol, terpineol, thixanol, butylceosolv acetate, and isophorone.

[0018] Such a conductive paste composition according to the present invention preferably includes, as an aspect, a pigment, preferably further containing an extender pigment.

[0019] A printed wiring board according to the present invention is characterized by using the conductive paste composition.

The invention's effect

[0020] According to the conductive paste composition of the present invention, a coating film having a sufficient thickness can be formed by a single coating operation.

[0021] Accordingly, a sufficiently high bump can be formed even with a smaller number of coatings than in the past.

[0022] Therefore, the number of overprints of the conductive paste composition can be reduced, and productivity can be improved. Further, since the conductive paste composition according to the present invention is of a non-firing type, it is not necessary to perform a calcining operation.

BEST MODE FOR CARRYING OUT THE INVENTION

[0023] <Conductive paste composition>

The conductive paste composition according to the present invention is characterized in that it comprises a phenolic resin, a melamine resin, a conductive powder, a solvent and a divalent alcohol having an ether bond. Here, “consisting of” means a conductive property in which other components other than the above essential components (that is, phenol resin, melamine resin, conductive powder, solvent and divalent alcohol having an ether bond) coexist. The paste composition is not excluded. That is, the conductivity according to the present invention The conductive paste composition includes both a conductive paste composition that only has the above essential components and a conductive paste composition that includes the above essential components and other components other than these essential components. In the above description, “conductive” means that the volume resistance value is at least 1 ^× 10 3 ^{_3 cm.Ω} or less.

[0024] The conductive paste composition according to the present invention preferably has a viscosity of 200 to 500? & '5, particularly 300 to 400 Pa's. This viscosity is measured with a spiral viscometer manufactured by Malcolm at 1 Orpm / min at 25 ° C.

[0025] The conductive paste composition according to the present invention preferably has a thixo index of 0.75 to L0, particularly 0.8 to 0.95. The thixo index is calculated from the viscosity of the conductive paste measured with a Malcolm spiral viscometer at 10 rpm Zmin, 5 rpm / min, and 25 ° C, using the thixo index calculation formula log (viscosity value at 5 rpm, viscosity at ZlO rpm. Value) Calculated with Zlog [10 (rpm) / 5 (rpm)]. The thixo index is an index that shows the property that the apparent viscosity increases when left standing and the apparent viscosity decreases when mixed vigorously, making it easier to coat.

[0026] (1) Phenolic resin

As the phenol resin used in the present invention, novolak type and resol type! Any of those having phenolic hydroxyl groups such as phenol, cresol, xylenol, polyparabuphenol, p-alkylphenol, chlorophenol, bisphenol A, phenolsulfonic acid, resorcin, etc. Preferred examples of the coconut resin include cocoa and the like obtained by adding and condensing aldehydes such as formalin and furfural. Of these, polyparabufenol is particularly preferred.

[0027] (2) Melamine rosin

Preferable examples of melamine rosin used in the present invention include methylol melamine and alkylated melamine.

[0028] (3) Conductive powder

Examples of the conductive powder used in the present invention include various conductive fine powders such as silver powder, gold powder, copper powder, nickel powder, platinum powder, palladium powder, solder powder, and metal powders such as metal alloy powders. Etc. can be used. These conductive powders can be used in combination of two or more. wear. Moreover, electroconductive powder other than a metal, for example, carbon powder, can also be used. The conductive powder may be surface-treated.

[0029] The form and size of the conductive powder are arbitrary as long as they are not contrary to the object of the present invention. In the present invention, for example, dendritic, flaky, spherical, and flaky forms, particularly preferably a mixture of flaky and spherical forms can be used. The average particle size is preferably 0.5 to 10 / ζ πι, particularly 1.0 to 5. O ^ m.

[0030] (4) Divalent alcohol and solvent having an ether bond

The conductive paste composition according to the present invention contains a divalent alcohol having an ether bond. In the present invention, among divalent alcohols having an ether bond, divalent alcohols having an ethylenedioxy moiety in the molecular structure are preferred, and divalent alcohols having hydroxy groups at both ends are particularly preferred! /. Examples of such preferred! / Compounds include diethylene glycol, triethylene glycol, tetraethylene glycol, pentaethylene glycol and hexaethylene glycol. Among these, triethylene glycol is particularly preferable. In the present invention, one kind selected from these divalent alcohol powers having an ether bond can be used alone, or two or more kinds can be used in combination.

[0031] As the solvent used in the present invention, for example, various kinds of organic solvents capable of forming a paste composition together with the above-mentioned phenol resin, melamine resin and conductive powder can be used. Preferable specific examples of such an organic solvent include, for example, butyl carbitol acetate, ethyl acetate, butyl acetate, ethyl acetate solve, butyl cetyl sorb, ethyl carbitol, butyl carbitol, isopropanol, butanol, terpineol, thixanol, butyl glycerol. Examples include sorb acetate, isophorone alone or a mixed solution thereof.

[0032] If the sum of the dihydric alcohol solvent having a ether bond is 100 mass%, the content of divalent alcohol having an ether bond, from 0.1 to 50 weight ^_0/0, preferably 0 5 to 40% by mass, more preferably 1 to 30% by mass.

[0033] (5) Components other than the above (arbitrary components)

The conductive paste composition according to the present invention can contain various components as required. The Specific examples of the components that can be included as needed include the following pigments, thixotropy-imparting agents, antifoaming agents, dispersants, antifungal agents, reducing agents, and the above-mentioned phenols. Other fat components (for example, epoxy resins and acrylic resins) that are miscible with fat and / or melamine resin can be used.

[0034] 纖

The conductive paste composition according to the present invention can contain various organic or inorganic pigments as needed, and the coating film of the conductive paste composition can be reinforced with such a pigment.

It is possible to add functions, improve workability, color and increase the amount.

In the present invention, extender pigments such as microsilica, calcium carbonate, barium sulfate, magnesium carbonate, alumina and the like can be used alone or as a mixture thereof.

[0036] (6) Mixing ratio

The blending ratio of each component in the conductive paste composition according to the present invention is as follows (in the following, the total of the rosin components means the total amount of phenol and melamine rosins. In addition, when there is a resin other than phenol resin or melamine resin, it means the total amount of each of these resin components).

[0037] The total amount of the solvent and the dihydric alcohol having an ether bond is 10

Preferably 0 to 10 parts by mass: LOO parts by mass, more preferably 30 to 80 parts by mass, and even more preferably 40 to 70 parts by mass.

[0038] The amount of the conductive powder is preferably 300 to L 100 parts by mass with respect to 100 parts by mass of the resin component.

More preferably, it is 500-900 mass parts.

[0039] The amount of the pigment is preferably 1 to 30 parts by mass, more preferably 5 to 25 parts by mass with respect to 100 parts by mass of the resin component.

[0040] The ratio of phenolic rosin and melamine rosin in the rosin component is expressed by mass ratio,

(Phenol resin) Z (Melamine resin) power preferably 10Z90 ~ 90ZlO, more preferably 3

The range is 0/70 to 70/30, more preferably 60/40 to 40/60.

[0041] (7) Use of conductive paste composition

The conductive paste composition according to the present invention has good conductivity and can be printed on a substrate by a known printing method such as a screen printing method or a metal mask printing method. It is a good one. Therefore, the conductive paste composition according to the present invention can be used in a wide range of fields as in the past.

[0042] Since the conductive paste composition according to the present invention has a thick coating film thickness per printing operation, it can efficiently form a sufficiently thick conductive layer. Is

[0043] Therefore, the conductive paste composition according to the present invention can form bumps having a sufficiently high height with fewer coatings than before, for example, even with only one coating. The productivity can be improved.

[0044] <Printed wiring board>

A printed wiring board according to the present invention is characterized by using the conductive paste composition described above.

[0045] Such a printed wiring board according to the present invention preferably includes, as an embodiment, a printed wiring board in which electrical connection between layers is made by bumps formed from the conductive paste composition.

Example

Has phenolic, melamine, silver powder, extender, solvent and ether linkage

Divalent alcohol was mixed at a mass ratio shown in Table 1, and sufficiently mixed with three rolls to produce a conductive paste composition according to the present invention. The viscosity and thixo index of this conductive paste composition are as shown in Table 1.

[0047] Using this conductive paste, screen (stencil) printing was performed. Specifically, φ 220

Use a metal mask plate made of aluminum with a hole of / z m, use a urethane resin squeegee with a hardness of 80 °, and control the environment to a temperature of 20 ° C and humidity of 50%.

Then, printing was performed to form bumps.

[0048] The height and shape of the formed bumps were evaluated. The results are as shown in Table 1.

[table 1] sl13004 <v ~

table 1

A conductive paste composition (comparative example) was produced in the same manner as in Example 1 except that the solvent was used in the proportions shown in Tables 2 and 3 and the divalent alcohol having an ether bond was removed. Then, screen printing was performed in the same manner as in the Examples, and the height and shape of the formed bumps were evaluated. The results are as described in Table 2.

[Table 2]

Table 2

Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Phenolic resin 50 50 50 50 50 50 Men resin 50 50 50 50 50 50 Silver powder 700 700 700 700 700 700 Extender pigment 1 0 1 0 10 1 0 1 0 1 0 Ptyl carbite sulfate 45 45 45 45 45 45

2 Butene 1 1 4 Diol 7.5

Pair 1 1 3 Butanediol 7.5

1-3 Provandiol 7.5

1—5 pentanediol 7.5

2 -3 Butanediol 7.5 Composition Propylene glycol

1 1 2-6 Hexanetriol

1 1 4 Butanediol

1 1 2 Butanediol

3 methyl 1 1 5 pentanediol

2-Methyl 2-4 pentanediol

Diethylene glycol monoethyl ester

Viscosity (P a · s / 25 ° C) 250 1 77 1 7 1 223 1 72 1 53 Thixo index 0. 50 0. 82 0. 69 0. 92 0. 60 0. 54 Pump height (m) 58 6 1 54 63 54 57 Pam shape Good Good Good Good Good Good

Physical properties

Table 3

Comparative Example 8 Comparative Example 9 Comparative Example 1 0 Comparative Example 1 1 Comparative Example 1 2 Comparative Example 1 3 Phenolic Resin 50 50 50 50 50 50 Men Resin 5 0 50 50 50 50 50 Silver Powder 700 7 00 700 700 700 700 Extender Pigment 1 0 1 0 1 0 1 0 1 0 1 0 Butyl carbite sulfate 45 45 45 45 45 45

2 Butene 1 1 4 Diol

Pair 1 1 3 Butanediol

1-3 propanediol

1 1 5 Pen Yundiol

2-3 Butanediol

Propylene glycol

1-2-6 Hexanetriol 7.5

1 1 4 Butanediol 7.5

1-2 butanediol 7.5

3 Methyl 1-5 Pentanediol 7.5

2 Methyl 2-4 Pentanediol 7.5

Diethylene glycol monoethyl ether 7.5 Viscosity (P a * s / 25 ° C) 2 1 0 1 85 1 50 1 58 1 52 144 Thixo index 0. 57 0. 74 0. 60 0. 53 0. 53 0. 62 Pam height (m) 62 57 54 53 57 54 Pam shape Good Good Good Good Good Good

[0050] <Evaluation>

As apparent from Table 1, Table 2 and Table 3 above, in Examples 1 to 7 containing a dihydric alcohol having a predetermined ether bond, bumps with a bump height of 75 μm to 86 μm ( Bump diameter: 220 μm) and does not use divalent alcohol with an ether bond. V ヽ Comparative example 1 (Bump height: 58 m, bump diameter: 220 μm) It can be seen that the rate is dramatically improved to 29-48%. Also, the bump shape was conical and was good.

[0051] In Comparative Examples 2 to 13 in which a monovalent, divalent or trivalent alcohol was used instead of the divalent alcohol having an ether bond used in Examples 1 to 7, the bump shape was rounded. Some were found to be lower in height. Moreover, even if it was high, the bump height was only increased by about 8.6%.

Claims

The scope of the claims

[1] A conductive paste composition comprising a phenolic resin, a melamine resin, a conductive powder, a solvent, and a divalent alcohol having an ether bond.

[2] The conductive paste composition according to [1], wherein the divalent alcohol having an ether bond has an ethylene dioxy moiety in its molecular structure.

[3] The conductive paste composition according to claim 1 or 2, wherein the divalent alcohol having an ether bond has hydroxy groups at both ends.

[4] Divalent alcohol having an ether bond Diethylene glycol, triethylene glycol, tetraethylene dallicol, pentaethylene glycol, and hexetylene glycol power The group force is at least one selected. Either

The conductive paste composition according to item 1.

[5] When the total of the solvent and the divalent alcohol having an ether bond is 100% by mass, the divalent alcohol having the ether bond is 0.1 to 50% by mass. The conductive paste composition according to any one of -4.

[6] The solvent is butyl carbitol acetate, ethyl acetate, butyl acetate, ethyl acetate oral solve, butynocello sonoleb, ethinorecanorebitonore, butinorecanolebitonore, isopropanol, butanol, terpineol, The conductive paste composition according to any one of claims 1 to 5, which contains at least one selected from the group strength of thixanol, butylcetosolve acetate, and isophorone.

[7] The conductive paste composition according to any one of claims 1 to 6, further comprising a pigment, preferably an extender pigment.

[8] A printed wiring board using the conductive paste composition according to any one of claims 1 to 7.