JP2012169559A - Method for manufacturing wiring board, and wiring board - Google Patents

Abstract

There is provided a highly reliable wiring board provided with a highly reliable conductor pattern in which generation of voids (cavities) around the conductor pattern is prevented.
A step of preparing a sheet-like temporary molded body 14 made of a material containing a ceramic material and a binder, and a composition 200 containing a polyhydric alcohol condensate on both surfaces of the temporary molded body 14 are applied. Thus, a step of obtaining a ceramic molded body 15 in which a region 13 containing a polyhydric alcohol condensate is formed in the vicinity of the surface, and a region of the ceramic molded body 15 containing the polyhydric alcohol condensate 13 in the metal particles and metal A conductive pattern forming ink 300 including a dispersion medium in which particles are dispersed is discharged by a droplet discharge method to form a conductive pattern precursor 10, and a plurality of the ceramic molded bodies 15 are stacked to form a stacked body 32. And a firing step of sintering the laminate 32 to obtain the wiring substrate 30 having the conductor pattern 20 and the ceramic substrate 31.
[Selection] Figure 1

Description

  The present invention relates to a method for manufacturing a wiring board and a wiring board.

As a circuit board (wiring board) on which electronic components are mounted, a ceramic circuit board in which wiring made of a metal material is formed on a board made of ceramics (ceramic board) is widely used. In such a ceramic circuit board, since the board (ceramic board) itself is made of a multifunctional material, it is advantageous in terms of formation of interior parts by multi-layering, dimensional stability, and the like.
Such a ceramic circuit board is provided with a composition containing metal particles in a pattern corresponding to a wiring (conductor pattern) to be formed on a ceramic molded body made of a material containing ceramic particles and a binder. Thereafter, the ceramic molded body to which the composition is applied is manufactured by degreasing and sintering.

  A screen printing method is widely used as a method for forming a pattern on a ceramic molded body. On the other hand, in recent years, miniaturization of wiring (for example, wiring with a line width of 60 μm or less) and high density circuit boards by narrowing the pitch have been demanded. It is disadvantageous for pitching and it is difficult to meet the above requirements. Therefore, in recent years, a so-called ink jet method has been proposed as a method for forming a pattern on a ceramic molded body, in which a liquid material containing metal particles (ink for forming a conductor pattern) is ejected in droplets from a liquid ejection head. (For example, refer to Patent Document 1).

  However, the conventional ink for forming a conductor pattern has a problem that voids are generated around the conductor pattern when the laminated ceramic molded body is degreased and sintered. When such a void is generated, the mechanical strength of the portion is lower than that of other portions, and as a result, there is a problem that cracks, disconnection, and the like occur.

JP 2007-84387 A

  An object of the present invention is to provide a highly reliable wiring board having a highly reliable conductor pattern in which generation of voids (cavities) around the conductor pattern is prevented, and to efficiently manufacture the wiring board. It is in providing the manufacturing method which can be performed.

Such an object is achieved by the present invention described below.
The method for manufacturing a wiring board according to the present invention includes a temporary molded body preparing step of preparing a sheet-shaped temporary molded body made of a material containing a ceramic material and a binder,
By applying a composition containing a polyhydric alcohol condensate to both surfaces of the temporary molded body, a polyhydric alcohol condensation is obtained in which a ceramic molded body in which a region containing the polyhydric alcohol condensate is formed near the surface is formed. An object imparting step;
Conductive pattern forming ink containing metal particles and a dispersion medium in which the metal particles are dispersed is ejected to a region containing the polyhydric alcohol condensate of the ceramic molded body by a droplet discharge method, thereby forming a conductor pattern precursor. A conductor pattern precursor forming step of forming
A laminating step of laminating a plurality of the ceramic molded bodies to obtain a laminated body;
And firing the laminate to obtain a wiring substrate having a conductor pattern and a ceramic substrate.

  As a result, there is provided a method of manufacturing a wiring board capable of efficiently manufacturing a highly reliable wiring board having a highly reliable conductor pattern in which generation of voids (cavities) around the conductor pattern is prevented. be able to. Moreover, the usage-amount of the condensate of a polyhydric alcohol can be suppressed, and the production cost of a wiring board can be suppressed. Moreover, generation | occurrence | production of a crack, a disconnection, a short circuit etc. can be prevented.

In the method for producing a wiring board of the present invention, the composition containing the polyhydric alcohol condensate includes a region to which the conductive pattern forming ink is applied, and a conductive pattern of the adjacent ceramic molded body in the laminate. It is preferable that it is selectively given to the region in contact with the precursor.
Thereby, it is possible to more efficiently prevent voids (cavities) from being generated around the conductor pattern, and in the ceramic molded body, a region to which a composition containing a polyhydric alcohol condensate is applied, and The affinity of the ink for forming the conductor pattern in the region other than the above can be made different, and excessive wetting and spreading of the ink for forming the conductor pattern on the ceramic molded body can be prevented. A wiring or the like having a smaller width can be more suitably formed.

In the method for manufacturing a wiring board according to the present invention, it is preferable that the composition containing the polyhydric alcohol condensate is applied by a droplet discharge method.
Thereby, the position selectivity at the time of providing the composition containing the condensate of a polyhydric alcohol can be made more excellent, and formation of a fine conductor pattern can be performed more suitably.

In the method for producing a wiring board according to the present invention, the polyhydric alcohol condensate preferably has a weight average molecular weight of 4000 or less.
Thereby, the reliability of a conductor pattern can be made higher.
In the method for manufacturing a wiring board according to the present invention, the composition preferably contains a condensate of ethylene glycol and / or glycerin as the condensate of the polyhydric alcohol.
Thereby, the reliability of a conductor pattern can be made higher.

In the method for producing a wiring board according to the present invention, the composition preferably contains polyethylene glycol and polyglycerin as the polyhydric alcohol condensate.
Thereby, the reliability of a conductor pattern can be made still higher.
In the method for manufacturing a wiring board according to the present invention, when the content of polyethylene glycol in the composition is X _PEG [wt%] and the content of polyglycerin in the composition is X _PG [wt%], 0 It is preferable that the relationship of 10 ≦ X _PEG / X _PG ≦ 0.70 is satisfied.
Thereby, the reliability of a conductor pattern can be made still higher.

In the method for manufacturing a wiring board of the present invention, the ceramic molded body preferably contains polyvinyl butyral as the binder.
Thereby, the reliability of a conductor pattern can be made higher.
In the method for manufacturing a wiring board according to the present invention, the ceramic molded body preferably contains an acrylic resin as the binder.
Thereby, the reliability of a conductor pattern can be made higher.

In the method for manufacturing a wiring board according to the present invention, it is preferable that the conductor pattern forming ink contains a polyglycerin compound.
Thereby, the reliability of a conductor pattern can be made higher.
In the method for manufacturing a wiring board of the present invention, it is preferable that the conductive pattern forming ink contains an aqueous dispersion medium as the dispersion medium.
Thereby, the reliability of a conductor pattern can be made higher.
The wiring board of the present invention is manufactured using the method of the present invention.
Thereby, it is possible to provide a highly reliable wiring board having a highly reliable conductor pattern in which generation of voids (cavities) around the conductor pattern is prevented.

It is sectional drawing which shows suitable embodiment of the manufacturing method of the wiring board (ceramics circuit board) of this invention. It is a perspective view which shows schematic structure of an inkjet apparatus. It is a schematic diagram for demonstrating schematic structure of an inkjet head.

Hereinafter, preferred embodiments of the present invention will be described in detail.
<Method for manufacturing wiring board>
FIG. 1 is a cross-sectional view showing a preferred embodiment of a method of manufacturing a wiring board (ceramic circuit board) according to the present invention, FIG. 2 is a perspective view showing a schematic configuration of an ink jet apparatus (droplet discharge apparatus), and FIG. FIG. 2 is a schematic diagram for explaining a schematic configuration of an inkjet head (droplet discharge head).

The method of manufacturing a wiring board according to the present embodiment includes a step of preparing a plurality of sheet-like temporary molded bodies 14 made of a material including a ceramic material and a binder (temporary molded body preparing step);
A region containing a polyhydric alcohol condensate near the surface (polyhydric alcohol) by applying a composition containing a polyhydric alcohol condensate (hereinafter also referred to as “polyhydric alcohol condensate”) to the temporary molded body 14. The metal particles and the metal particles are dispersed on at least one surface of the ceramic molded body 15 and the step of obtaining the ceramic molded body 15 in which the condensate-containing portion 13) is formed (polyhydric alcohol condensate imparting step). A conductor pattern forming ink 300 containing a dispersion medium is ejected by a droplet ejection method to form a conductor pattern precursor 10 (conductor pattern precursor forming process), and a plurality of ceramic molded bodies 15 are laminated. A step of obtaining the multilayer body 17 (lamination step) and a step of heating the multilayer body 17 to obtain the wiring substrate 30 having the conductor pattern 20 and the ceramic substrate 31. And a firing step) and.

(Temporary molded body preparation process)
In this step, a plurality of sheet-like temporary molded bodies 14 made of a material containing a ceramic material and a binder are prepared.
<Temporary molded product>
The temporary molded body 14 becomes the ceramic molded body 15 by being given a polyhydric alcohol condensate.

When obtaining the temporary molded body 14 containing a plurality of types of powder, it is preferable to mix the plurality of types of powder in advance prior to mixing with a binder or the like.
A ceramic powder (ceramic material) having an average particle size of 0.1 μm or more and 10 μm or less and a glass powder having an average particle size of 0.1 μm or more and 10 μm or less are prepared, and these are mixed at an appropriate mixing ratio, for example, a weight of 1: 1. Can be mixed in a ratio.
Such ceramic _{materials, Al 2 O 3, SiO 2} , MgO, MgO · SiO 2, 2MgO · SiO 2 and _{TiO 2, BaTiO 3, Ba x} Sr 1-x TiO 3, SrTiO 3, CaTiO 3, PbZr _x Ti _1-x , Pb _1-x La _y ZrTi _1-x O ₃ , SrBi ₂ TaO ₃ and other composite oxides and other ferroelectric materials having a perovskite structure, or MgTiO ₃ , Ba (Mg _{1 / 3} Ta _2/3 ) O ₃ , Ba (Zn _1/3 Ta _2/3 ) O ₃ , Ba (Ni _1/3 Ta _2/3 ), Ba (Co _1/3 Ta _2/3 ), BaNd ₂ Ti ₄ O ₁₂ , Ba ₂ Ti ₉ O ₂₀ , LaAlO ₃ , PrAlO ₃ , SmAlO ₃ , YAlO ₃ , GdAlO ₃ , DyAlO ₃ , ErAlO ₃ , Sr (Zn _1/3 Ta _2/3 ) O ₃ , Sr (Ni _1/3 Ta _2/3 ) O ₃ , Sr (Co _1/3 Ta _2/3 ) O ₃ , Sr (Mg _1/3 Ta _2/3 ) O ₃ , Sr (Ca _1/3 Ta _2/3 ) O ₃ , Ba ₂ Ti ₉ O ₂₀ , Ba (Co _1/3 Nb _2/3 ) O ₃ etc. Although it is possible, any general ceramic material can be used.

As the glass component, either a crystallized glass or an amorphous glass can be used as long as it is a general glass. Examples thereof include those containing SiO ₂ , Al ₂ O ₃ , RO (R is Mg, Ca, Sr, Ba), and specifically include SiO ₂ —BaO series, SiO ₂ —Al ₂ O ₃ —BaO. , SiO ₂ —Al ₂ O ₃ —BaO—B ₂ O ₃ system, SiO ₂ —Al ₂ O ₃ —BaO—ZnO—B ₂ O ₃ system glass, Bi glass, and glass containing them as a main component Etc. are available.
The mixing ratio of the ceramic powder and the glass powder is preferably 2: 1 to 1: 2 by weight.
A slurry is obtained by mixing and stirring the above raw material powder with a binder (binder) or the like.

  As the binder, polyvinyl butyral can be suitably used. Polyvinyl butyral is insoluble in water and easily dissolved or swelled in a so-called oil-based organic solvent. In addition, by using polyvinyl butyral as a binder, the polyhydric alcohol condensate provided in the step described later can be reliably held near the surface of the ceramic molded body 15, and the polyhydric alcohol as described in detail later. The function of the condensate can be exhibited more effectively. As a result, the reliability of the finally obtained wiring board 30 (formed conductor pattern 20) can be made higher.

As the binder, the binder may be an acrylic resin (acrylic acid, methacrylic acid or a homopolymer or copolymer thereof, specifically an acrylic ester copolymer, a methacrylic ester copolymer). A polymer, an acrylic ester-methacrylic ester copolymer, etc.) can be preferably used. The acrylic resin is insoluble in water and easily dissolved or swelled in a so-called oil-based organic solvent. Further, by using an acrylic resin as the binder, the polyhydric alcohol condensate imparted in the steps described later can be reliably held near the surface of the ceramic molded body 15, and the polyvalent alcohol described in detail later. The function of the alcohol condensate can be exhibited more effectively. As a result, the reliability of the finally obtained wiring board 30 (formed conductor pattern 20) can be made higher. In addition, those conventionally used for ceramic green sheets can be used. For example, a homopolymer or copolymer such as polyvinyl alcohol, acrylic-styrene, polypropylene carbonate, or cellulose may be used. it can.
In the preparation of the slurry, a plasticizer, an organic solvent (functioning as a dispersion medium for dispersing the raw material powder), a dispersant, and the like may be used.
The temporary molded body 14 is obtained by forming the slurry as described above into a sheet shape.

The temporary molded body 14 can be suitably obtained by forming a slurry into a sheet shape on a PET film using, for example, a doctor blade, a reverse coater, or the like.
The thickness of the temporary molded body 14 is preferably several μm or more and several hundreds μm or less.
The temporary molded body 14 formed into a sheet shape as described above is usually wound on a roll, cut according to the use of the product, and further cut into a sheet having a predetermined size. In this embodiment, for example, it is cut into a square shape having a side length of 200 mm.

Further, through holes (through holes) are formed at predetermined positions by drilling with a CO ₂ laser, a YAG laser, a mechanical punch or the like as necessary. In addition, formation of a through hole may be performed at this process, and may be performed at a subsequent process (for example, after a polyhydric alcohol condensate provision process).
Then, by filling this through hole with a thick film conductive paste in which metal particles are dispersed, a portion (conductor post 16) to be the contact 33 is formed. As the thick film conductive paste, a conductor pattern forming ink as described later can be used. The filling of the thick film conductive paste may be performed in this step, may be performed in a conductor pattern precursor forming step described later, or is performed after the conductor pattern precursor forming step. It may be a thing.

(Polyhydric alcohol condensate application process (ceramic molded body manufacturing process))
In this step, a ceramic green sheet (ceramic molded body) 15 is obtained by applying a composition containing a polyhydric alcohol condensate (polyhydric alcohol condensate-containing composition) to both surfaces of the temporary molded body 14. The ceramic molded body (ceramic green sheet) 15 obtained in this step contains a polyhydric alcohol condensate containing part 13 containing a polyhydric alcohol condensate provided in a part near the surface and a polyhydric alcohol condensate. The polyhydric alcohol condensate-free portion 19 is not included.

  By the way, when the ceramic molded body containing the polyhydric alcohol condensate on one side is laminated and fired in the firing step described later, it does not include the surface containing the polyhydric alcohol condensate that is in contact. Since the thermal contraction rate or the thermal expansion coefficient is particularly different from the surface, there is a problem that voids (cavities) are generated in the vicinity of the interface, particularly around the conductor pattern. When such a void is generated, the mechanical strength of the portion is lower than that of other portions, and as a result, there is a problem that cracks, disconnection, and the like occur.

  In response to such a problem, in the present invention, by applying the polyhydric alcohol condensate-containing composition to both surfaces of the temporary molded body, the difference in thermal shrinkage rate or thermal expansion coefficient at the interface between adjacent ceramic molded bodies is reduced. It is possible to prevent the generation of voids (cavities) around the conductor pattern. As a result, the reliability of the formed conductor pattern can be increased.

  Further, since the ceramic molded body 15 contains a polyhydric alcohol condensate as in this step, the conductor discharged onto the ceramic molded body 15 in a step (conductor pattern precursor forming step) described in detail later. The dispersion medium, which is a component of the conductor pattern forming ink, can be absorbed into the ceramic molded body 15 from the pattern forming ink 300, and a layer (conductor pattern) in which metal particles are concentrated on the ceramic molded body 15. A precursor 10) can be formed. As a result, it is possible to effectively prevent unintentional movement of the metal particles contained in the conductive pattern forming ink 300 discharged onto the ceramic molded body 15 from the landing position. It can be obtained as a highly reliable conductor pattern 20 having a desired shape, in which the occurrence of cracks, disconnections, short circuits, etc. is reliably prevented.

  Further, since the dispersion medium, which is a constituent component of the conductor pattern forming ink 300, can be absorbed into the ceramic molded body 15 from the conductor pattern forming ink 300 discharged onto the ceramic molded body 15, the conductive pattern forming Even if the content rate of the dispersion medium contained in the ink 300 is relatively high, the metal particles contained in the conductor pattern forming ink 300 discharged onto the ceramic molded body 15 are unwilling from the landing position. In the conductor pattern forming ink is absorbed, the solid ratio of the conductor pattern forming ink is increased, and the wiring becomes hard when pressurizing. Crushing can be suppressed. As a result, the final wiring board 30 can be obtained as a highly reliable circuit with a stable line width provided with a conductor pattern 20 of a desired shape, which reliably prevents the occurrence of cracks, disconnections, short circuits, and the like. it can. In addition, since the metal particles contained in the conductive pattern forming ink 300 discharged onto the ceramic molded body 15 can be reliably prevented from unintentional movement from the landing position, the discharged conductive pattern forming ink 300 is used. The discharge stability of the conductive pattern forming ink 300 can be made particularly excellent. Thereby, the productivity and the yield of the wiring board 30 can be made particularly excellent.

In addition, the amount of the polyhydric alcohol condensate used can be suppressed by applying the polyhydric alcohol condensate-containing composition to the temporary molded body 14 to obtain the ceramic molded body 15. Cost can be suppressed.
The excellent effects as described above can be obtained by producing a ceramic molded body to which the conductive pattern forming ink is applied using a polyhydric alcohol condensate-containing composition. It cannot be obtained when a polyhydric alcohol condensate is contained in the conductor pattern forming ink.

  The polyhydric alcohol condensate-containing composition to be imparted to the temporary molded body 14 may be any of liquid, solid, and gaseous forms, for example, may be molded into a predetermined shape, It is preferably liquid. Accordingly, the polyhydric alcohol condensate-containing composition can be easily stored, and the application pattern of the polyhydric alcohol condensate-containing composition can be easily adapted to the ceramic green sheet (ceramic molded body) 15 to be formed. Can be adjusted. In addition, when the polyhydric alcohol condensate-containing composition is liquid, the viscosity is not particularly limited, but is preferably 2.0 mPa · s or more and 12.0 mPa · s or less, and preferably 5.0 mPa · s. More preferably, it is 10.0 mPa · s or less. Thereby, the polyhydric alcohol condensate-containing composition can be suitably used for droplet discharge as described later.

In the following description, the case where the polyhydric alcohol condensate-containing composition is a liquid composition (polyhydric alcohol condensate-containing ink) will be representatively described.
<Polyhydric alcohol condensate-containing composition (polyhydric alcohol condensate-containing ink)>
[Polyhydric alcohol condensate]
In the present invention, as the polyhydric alcohol condensate, a condensate of a compound having a plurality of hydroxyl groups in the molecule (polyhydric alcohol as a monomer) can be used.

The weight average molecular weight of the polyhydric alcohol condensate is preferably 4000 or less, more preferably 250 or more and 3900 or less, and further preferably 300 or more and 3800 or less. Thereby, the reliability of a conductor pattern can be made higher.
Examples of the polyhydric alcohol constituting the polyhydric alcohol condensate include ethylene glycol, glycerin, propylene glycol (1,2-propanediol), 1,3-propanediol, 1,3-butylene glycol, erythritol, and xylitol. And reducing polysaccharides such as sorbitol.

As a polyhydric alcohol condensate, the compound obtained by condensing 1 type (s) or 2 or more types among the above polyhydric alcohols can be used conveniently, for example.
Of these, the polyhydric alcohol condensate is preferably a condensate of ethylene glycol and / or glycerin. Thereby, the ceramic molded body 15 can moderately absorb the dispersion medium constituting the conductor pattern forming ink 300, and the reliability of the manufactured wiring board 30 (formed conductor pattern 20) is higher. can do.

  The polyhydric alcohol condensate-containing composition preferably contains polyethylene glycol and polyglycerin as the polyhydric alcohol condensate. Thereby, the ceramic molded body 15 can moderately absorb the dispersion medium constituting the conductor pattern forming ink 300, and the reliability of the manufactured wiring board 30 (formed conductor pattern 20) is further enhanced. can do.

When the polyhydric alcohol condensate-containing composition contains polyethylene glycol and polyglycerin as the polyhydric alcohol condensate, the content of polyethylene glycol in the polyhydric alcohol condensate-containing composition is expressed as X _PEG [wt%] When the polyglycerin content in the polyhydric alcohol condensate-containing composition is X _PG [wt%], it is preferable to satisfy the relationship of 0.10 ≦ X _PEG / X _PG ≦ 0.70. It is more preferable to satisfy the relationship of 20 ≦ X _PEG / X _PG ≦ 0.60. By satisfying such a relationship, the ceramic molded body 15 can appropriately absorb the dispersion medium constituting the conductor pattern forming ink 300, and the produced wiring board 30 (conductor pattern 20 to be formed) Reliability can be further increased.

In the present invention, as the polyhydric alcohol condensate, one having at least a part of the terminal hydroxyl group modified (for example, esterification, etherification, etc.) may be used. It is preferable to have it.
The content of the polyhydric alcohol condensate in the polyhydric alcohol condensate-containing composition (polyhydric alcohol condensate-containing ink) is not particularly limited, but is preferably 5 wt% or more and 75 wt% or less, and preferably 7 wt% or more. More preferably, it is 70 wt% or less. Thereby, the polyhydric alcohol condensate can be surely infiltrated in the vicinity of the surface of the temporary molded body 14, and the functions as described above can be exhibited more effectively.

[Other ingredients]
The polyhydric alcohol condensate-containing composition (polyhydric alcohol condensate-containing ink) may contain components other than the polyhydric alcohol condensate.
Examples of such components include water, pH adjusters, penetrants, surfactants, humectants and the like.
When such a component (hereinafter referred to as “other component”) is included, the content of the other component in the polyhydric alcohol condensate-containing composition (polyhydric alcohol condensate-containing ink) is 25 wt% or more and 95 wt%. It is preferable that:

  The polyhydric alcohol condensate-containing composition (polyhydric alcohol condensate-containing ink) may be applied to the entire surface of both surfaces of the temporary molded body 14, or may be applied to a part of both surfaces of the temporary molded body 14. The conductive pattern forming ink 300 may be selectively applied to the region to which the conductive pattern forming ink 300 is applied and the region in contact with the conductive pattern precursor 10 of the adjacent ceramic molded body 15 when laminated. It is preferred that As a result, the difference in thermal contraction rate or thermal expansion coefficient at the interface between adjacent ceramic molded bodies can be reduced more effectively, and voids (cavities) can be more efficiently prevented from occurring around the conductor pattern. be able to. As a result, the reliability of the formed conductor pattern can be made higher.

  The polyhydric alcohol condensate-containing composition (polyhydric alcohol condensate-containing ink) may be applied to the temporary molded body 14 by any method, but is preferably applied by a droplet discharge method. Thereby, the position selectivity at the time of providing the composition containing a polyhydric alcohol condensate can be made more excellent, and formation of the fine conductor pattern 20 can be performed more suitably.

  When the polyhydric alcohol condensate-containing composition (polyhydric alcohol condensate-containing ink) is applied by a droplet discharge (inkjet) method, the polyhydric alcohol condensate-containing composition (polyhydric alcohol condensate-containing ink) 200 is discharged. For example, the ink jet device (droplet discharge device) 100 shown in FIGS. 2 and 3 can be used. Hereinafter, the ink jet apparatus 100 and droplet discharge using the ink jet apparatus 100 will be described.

FIG. 2 is a perspective view of the ink jet apparatus 100. In FIG. 2, the X direction is the left-right direction of the base 130, the Y direction is the front-rear direction, and the Z direction is the up-down direction.
The ink jet apparatus 100 includes an ink jet head (droplet discharge head; hereinafter simply referred to as “head”) 110, a base 130, a table 140, a control device 190, a table positioning means 170, and a head positioning means shown in FIG. 180.

The base 130 is a table that supports each component of the droplet discharge device 100 such as the table 140, the table positioning unit 170, and the head positioning unit 180.
The table 140 is installed on the base 130 via the table positioning means 170. The table 140 is used for placing the base material S (the temporary molded body 14 in this step).

The table positioning unit 170 includes a first moving unit 171 and a motor 172. The table positioning means 170 determines the position of the table 140 in the base 130, and thereby determines the position of the temporary molded body 14 in the base 130.
The first moving means 171 has two rails provided substantially parallel to the Y direction and a support base that moves on the rails. The support base of the first moving means 171 supports the table 140 via the motor 172. Then, as the support base moves on the rail, the table 140 on which the base material S is placed is moved and positioned in the Y direction.

The motor 172 supports the table 140 and swings and positions the table 140 in the θz direction.
The head positioning unit 180 includes a second moving unit 181, a linear motor 182, and motors 183, 184 and 185. The head positioning unit 180 determines the position of the head 110.

  The second moving means 181 is provided with two support pillars standing from the base 130, a support base provided between the support pillars, the rail support having two rails, and the rails. And a support member (not shown) for supporting the head 110. Then, as the support member moves along the rail, the head 110 is moved and positioned in the X direction.

The linear motor 182 is provided in the vicinity of the support member, and can move and position the head 110 in the Z direction.
Motors 183, 184, and 185 swing and position the head 110 in the α, β, and γ directions, respectively.
By the table positioning unit 170 and the head positioning unit 180 as described above, the ink jet apparatus 100 accurately controls the relative position and posture of the ink ejection surface 115P of the head 110 and the base material S on the table 140. It can be done.

  As shown in FIG. 3, the head 110 ejects a polyhydric alcohol condensate-containing ink 200 (hereinafter, also simply referred to as “ink 200”) from a nozzle (projection) 118 by an ink jet method (droplet ejection method). Is. In the present embodiment, the head 110 uses a piezo method in which ink is ejected using a piezo element 113 as a piezoelectric element. The piezo method has an advantage that the composition of the material is not affected because heat is not applied to the ink 200.

The head 110 has a head body 111, a diaphragm 112, and a piezo element 113.
The head main body 111 has a main body 114 and a nozzle plate 115 on the lower end surface thereof. Then, the main body 114 is sandwiched between the plate-like nozzle plate 115 and the vibration plate 112 to form a reservoir 116 as a space and a plurality of ink chambers 117 branched from the reservoir 116.

Ink 200 is supplied to the reservoir 116 from an ink tank (not shown). The reservoir 116 forms a flow path for supplying the ink 200 to each ink chamber 117.
The nozzle plate 115 is attached to the lower end surface of the main body 114 and constitutes an ink ejection surface 115P. In the nozzle plate 115, a plurality of nozzles 118 that discharge the ink 200 are opened corresponding to the ink chambers 117. An ink flow path is formed from each ink chamber 117 toward the corresponding nozzle 118.

The diaphragm 112 is attached to the upper end surface of the head body 111 and constitutes the wall surface of each ink chamber 117. The diaphragm 112 can vibrate according to the vibration of the piezo element 113.
The piezo element 113 is provided corresponding to each ink chamber 117 on the opposite side of the vibration plate 112 from the head body 111. The piezoelectric element 113 is obtained by sandwiching a piezoelectric material such as quartz with a pair of electrodes (not shown). The pair of electrodes is connected to the drive circuit 191.

  When an electric signal is input from the drive circuit 191 to the piezo element 113, the piezo element 113 is expanded or contracted. When the piezo element 113 contracts and deforms, the pressure in the ink chamber 117 decreases, and the ink 200 flows from the reservoir 116 into the ink chamber 117. When the piezo element 113 expands and deforms, the pressure in the ink chamber 117 increases and the ink 200 is ejected from the nozzle 118. Note that the amount of deformation of the piezo element 113 can be controlled by changing the applied voltage. Further, the deformation speed of the piezo element 113 can be controlled by changing the frequency of the applied voltage. That is, by controlling the voltage applied to the piezo element 113, the ejection conditions of the ink 200 can be controlled.

The control device 190 controls each part of the inkjet device 100. For example, by adjusting the waveform of the applied voltage generated by the drive circuit 191 to control the ejection conditions of the ink 200, or by controlling the head positioning unit 180 and the table positioning unit 170, the ejection position of the ink 200 onto the substrate S To control.
By using the ink jet apparatus 100 as described above, the ink 200 can be accurately ejected to a desired location on the temporary molded body 14 (base S) with a desired amount.

(Conductor pattern precursor formation process)
A conductive pattern forming ink 300 as described in detail later is applied to the surface of at least one side of the ceramic green sheet (ceramic molded body) 15 obtained as described above by a droplet discharge (inkjet) method, A conductor pattern precursor 10 to be the circuit 20 is formed. Thereby, the ceramic molded body 15 provided with the precursor 10 is obtained.
And the conductor pattern precursor 10 fuse | melts metal particles by sintering, and forms the conductor pattern 20 mentioned later.

Hereinafter, the conductive pattern forming ink 300 used in this step will be described in detail.
<Conductor pattern forming ink>
The conductor pattern forming ink 300 is ink used to form the conductor pattern precursor 10 by a droplet discharge method.
In the present embodiment, a case where a dispersion liquid in which silver particles as metal particles are dispersed in an aqueous dispersion medium is used as the conductor pattern forming ink 300 will be representatively described.

Hereinafter, each component of the conductive pattern forming ink 300 will be described in detail.
[Aqueous dispersion medium]
In the present embodiment, the conductor pattern forming ink 300 includes an aqueous dispersion medium. As described above, since the conductor pattern forming ink 300 contains an aqueous dispersion medium as a dispersion medium, the dispersion medium is more preferably removed from the conductor pattern formation ink 300 discharged onto the ceramic molded body 15. 15, and a layer (conductor pattern precursor 10) in which metal particles are concentrated can be more suitably formed on the ceramic molded body 15. As a result, the reliability of the formed conductor pattern 20 can be made higher.

  In the present invention, the “aqueous dispersion medium” refers to a liquid composed of water and / or a liquid having excellent compatibility with water (for example, a liquid having a solubility in 100 g of water at 25 ° C. of 30 g or more). . As described above, the aqueous dispersion medium is composed of water and / or a liquid having excellent compatibility with water, but is preferably composed mainly of water. It is preferably 70 wt% or more, more preferably 90 wt% or more. Thereby, the effect mentioned above is exhibited more notably.

Specific examples of the aqueous dispersion medium include, for example, water, methanol, ethanol, butanol, propanol, isopropanol and other alcohol solvents, 1,4-dioxane, tetrahydrofuran (THF) and other ether solvents, pyridine, pyrazine, pyrrole and the like. Aromatic heterocyclic compound solvents, amide solvents such as N, N-dimethylformamide (DMF) and N, N-dimethylacetamide (DMA), nitrile solvents such as acetonitrile, and aldehyde solvents such as acetaldehyde. Of these, one or a combination of two or more can be used.
The content of the aqueous dispersion medium in the conductor pattern forming ink 300 is preferably 20 wt% or more and 80 wt% or less, and more preferably 25 wt% or more and 70 wt% or less. Thereby, while making the viscosity of the ink 300 for conductor pattern formation suitable, the change of the viscosity by volatilization of a dispersion medium can be made small.

[Silver particles]
Next, silver particles (metal particles) will be described.
Silver particles are a main component of the conductor pattern 20 to be formed, and are components that impart conductivity to the conductor pattern 20.
Silver particles are dispersed in the conductive pattern forming ink 300.

  The average particle diameter of the silver particles is preferably 1 nm or more and 100 nm or less, and more preferably 10 nm or more and 30 nm or less. As a result, the ejection stability of the conductor pattern forming ink 300 can be made higher, and a fine conductor pattern can be easily formed. In the present specification, the “average particle size” means a volume-based average particle size unless otherwise specified.

Further, in the conductive pattern forming ink 300, the average interparticle distance of silver particles is preferably 1.7 nm or more and 380 nm or less, and more preferably 1.75 nm or more and 300 nm or less. Thereby, the viscosity of the ink 300 for forming a conductor pattern can be made more appropriate, and the discharge stability is particularly excellent.
Further, the content of silver particles (silver particles (metal particles) in which the dispersant is not adsorbed on the surface) contained in the conductor pattern forming ink 300 is preferably 0.5 wt% or more and 60 wt% or less, More preferably, it is 10 wt% or more and 45 wt% or less. Thereby, the disconnection of the conductor pattern 20 can be prevented more effectively, and the conductor pattern 20 with higher reliability can be provided.
The silver particles (metal particles) are preferably dispersed in an aqueous dispersion medium as silver colloid particles (metal colloid particles) having a dispersant attached to the surface thereof. Thereby, the dispersibility of the silver particles in the aqueous dispersion medium is particularly excellent, and the discharge stability of the conductive pattern forming ink 300 is particularly excellent.

Although it does not specifically limit as a dispersing agent, it has 3 or more of COOH groups and OH groups, and the number of COOH groups is the same as that of OH groups, or contains hydroxy acid or its salt more than it. Is preferred. These dispersants adsorb on the surface of silver particles to form colloidal particles, and the colloidal liquid is stabilized by uniformly dispersing silver colloidal particles in an aqueous solution by the electric repulsive force of COOH groups present in the dispersant. Has the function of As described above, since the silver colloid particles are stably present in the conductor pattern forming ink 300, the fine conductor pattern 20 can be more easily formed. Further, silver particles are uniformly distributed in the pattern (precursor 10) formed by the conductor pattern forming ink 300, and cracks, disconnections, and the like are less likely to occur. On the other hand, if the number of COOH groups and OH groups in the dispersant is less than 3 or the number of COOH groups is less than the number of OH groups, the dispersibility of the silver colloid particles cannot be sufficiently obtained. There is a case.
Examples of such a dispersing agent include citric acid, malic acid, trisodium citrate, tripotassium citrate, trilithium citrate, triammonium citrate, disodium malate, tannic acid, gallotannic acid, and pentaploid tannin. Of these, one or a combination of two or more can be used.

  Further, the dispersant may contain mercapto acid or a salt thereof having two or more COOH groups and SH groups. In these dispersants, mercapto groups are adsorbed on the surface of silver fine particles to form colloidal particles, and colloidal particles are uniformly dispersed in an aqueous solution by the electric repulsive force of COOH groups present in the dispersant. Has the function of stabilizing As described above, since the silver colloid particles are stably present in the conductor pattern forming ink 300, the fine conductor pattern 20 can be more easily formed. Further, silver particles are uniformly distributed in the pattern (precursor 10) formed by the conductor pattern forming ink 300, and cracks, disconnections, and the like are less likely to occur. On the other hand, when the number of COOH groups and SH groups in the dispersant is less than 2, that is, only one, the dispersibility of the silver colloidal particles may not be sufficiently obtained.

  Examples of such dispersants include mercaptoacetic acid, mercaptopropionic acid, thiodipropionic acid, mercaptosuccinic acid, thioacetic acid, sodium mercaptoacetate, sodium mercaptopropionate, sodium thiodipropionate, disodium mercaptosuccinate, Examples include potassium mercaptoacetate, potassium mercaptopropionate, potassium thiodipropionate, dipotassium mercaptosuccinate, and the like, and one or more of these can be used in combination.

  The content of the silver colloid particles in the conductor pattern forming ink 300 is preferably 1 wt% or more and 60 wt% or less, and more preferably 5 wt% or more and 50 wt% or less. When the content of the silver colloid particles is less than the lower limit, the silver content is small, and when the conductive pattern 20 is formed, it is necessary to apply the coating multiple times when a relatively thick film is formed. On the other hand, when the content of the silver colloidal particles exceeds the upper limit, the silver content increases and the dispersibility decreases. To prevent this, the frequency of stirring increases.

  Further, the heat loss to 500 ° C. in the thermogravimetric analysis of the silver colloid particles is preferably 1 wt% or more and 25 wt% or less. When the colloidal particles (solid content) are heated to 500 ° C., the dispersant adhering to the surface, the reducing agent (residual reducing agent) described later, etc. are oxidatively decomposed, and most of them are gasified and disappear. Since the amount of the residual reducing agent is considered to be small, the weight loss due to heating up to 500 ° C. is considered to substantially correspond to the amount of the dispersant in the silver colloid particles. When the loss on heating is less than 1 wt%, the amount of the dispersant with respect to the silver particles is small, and the sufficient dispersibility of the silver particles is lowered. On the other hand, when it exceeds 25 wt%, the amount of the residual dispersant with respect to the silver particles increases, and the specific resistance of the conductor pattern increases. However, the specific resistance can be improved to some extent by heating and sintering after formation of the conductor pattern 20 to decompose and disappear organic components. Therefore, it is effective for a ceramic substrate that is sintered at a higher temperature.

[Organic binder]
Further, the conductor pattern forming ink 300 may contain an organic binder. The organic binder prevents aggregation of silver particles in the conductor pattern precursor 10 formed using the conductor pattern forming ink 300. That is, in the formed conductor pattern precursor 10, the organic binder can be prevented from being agglomerated with each other due to the presence of the organic binder between the silver particles and causing cracks in a part of the pattern. Further, at the time of sintering, the organic binder can be decomposed and removed, and the silver particles in the conductor pattern precursor 10 are combined to form the conductor pattern 20.

  In addition, since the conductive pattern forming ink 300 contains an organic binder, the adhesion of the conductive pattern precursor 10 to the ceramic molded body 15 (ceramic molded body 15 containing a polyhydric alcohol condensate) is particularly excellent. It is possible to prevent the metal particles constituting the conductor pattern precursor 10 from flowing out to unintentional portions more reliably. As a result, the occurrence of cracks, disconnections, short circuits, etc. can be more effectively prevented, and the conductor pattern 20 can be formed with higher accuracy. That is, the reliability of the finally obtained conductor pattern 20 can be made particularly high.

  Although it does not specifically limit as an organic binder, For example, polyethyleneglycol # 200 (weight average molecular weight 200), polyethyleneglycol # 300 (weight average molecular weight 300), polyethyleneglycol # 400 (average molecular weight 400), polyethyleneglycol # 600 ( Weight average molecular weight 600), polyethylene glycol # 1000 (weight average molecular weight 1000), polyethylene glycol # 1500 (weight average molecular weight 1500), polyethylene glycol # 1540 (weight average molecular weight 1540), polyethylene glycol # 2000 (weight average molecular weight 2000), etc. Polyethylene glycol, polyvinyl alcohol # 200 (weight average molecular weight: 200), polyvinyl alcohol # 300 (weight average molecular weight: 300), polyvinyl alcohol # 400 (average molecular weight: 400), polyvinyl alcohol # 600 (weight average molecular weight: 600), polyvinyl alcohol # 1000 (weight average molecular weight: 1000), polyvinyl alcohol # 1500 (weight average molecular weight: 1500), polyvinyl alcohol # Polyglycerin compounds having a polyglycerin skeleton such as polyvinyl alcohol such as 1540 (weight average molecular weight: 1540), polyvinyl alcohol # 2000 (weight average molecular weight: 2000), polyglycerin, polyglycerin ester, etc. Alternatively, two or more kinds can be used in combination. Examples of polyglycerol esters include polyglycerol monostearate, tristearate, tetrastearate, monooleate, pentaoleate, monolaurate, monocaprylate, polycinnolate, sesquistearate, decaoleate, and sesquioleate. Etc.

Among these, when a polyglycerin compound is used as the organic binder, the following effects can be obtained.
The polyglycerin compound particularly suitably prevents the conductor pattern precursor 10 from cracking when the conductor pattern precursor 10 formed using the conductor pattern forming ink 300 is dried (dedispersing medium). be able to. This is considered as follows. By including the polyglycerin compound in the conductive pattern forming ink 300, a polymer chain exists between the silver particles (metal particles), and the polyglycerin compound makes the distance between the silver particles moderate. be able to. Furthermore, since the polyglycerin compound has a relatively high boiling point, it is not removed when the aqueous dispersion medium is removed, and adheres around the silver particles. As described above, at the time of removing the aqueous dispersion medium, the polyglycerin compound continuously encapsulates the silver particles, and as a result, rapid volume shrinkage due to volatilization of the aqueous dispersion medium is avoided and silver grain growth (aggregation) is hindered. It is considered that generation of cracks in the conductor pattern precursor 10 is suppressed.

In addition, the polyglycerin compound can more reliably prevent the occurrence of disconnection during sintering when the conductor pattern 20 is formed. This is considered as follows. Polyglycerin compounds have a relatively high boiling point or decomposition temperature. For this reason, in the process of forming the conductor pattern 20 from the conductor pattern precursor 10, the conductor pattern is not evaporated or thermally (oxidized) decomposed to a relatively high temperature after the water-based dispersion medium evaporates. It can be present in the precursor 10. Therefore, until the polyglycerin compound evaporates or is thermally (oxidized) decomposed, the polyglycerin compound exists around the silver particles, and the approach and aggregation of the silver particles can be suppressed, and the polyglycerin compound is decomposed. Later, the silver particles can be joined more uniformly. Furthermore, a polymer chain (polyglycerin compound) exists between silver particles (metal particles) in the pattern during sintering, and the polyglycerin compound can keep the distance between the silver particles. Moreover, this polyglycerin compound has moderate fluidity | liquidity. For this reason, by including the polyglycerin compound, the conductor pattern precursor 10 has excellent followability to expansion / contraction due to temperature change of the ceramic molded body 15.
From the above, it is considered that disconnection of the formed conductor pattern 20 can be more reliably prevented.

Further, by including such a polyglycerin compound, the viscosity of the conductive pattern forming ink 300 can be made more appropriate, and the ejection stability from the inkjet head 110 can be more effectively improved. . In addition, film formability can be improved.
Among the above-mentioned polyglycerin compounds, polyglycerin is preferably used. Polyglycerin is particularly excellent in the ability to follow expansion and contraction due to temperature changes of the ceramic molded body 15 and is a component that can be more reliably removed from the conductor pattern 20 after the ceramic molded body 15 is sintered. . As a result, the electrical characteristics of the conductor pattern 20 can be made higher. Furthermore, since polyglycerin has high solubility in an aqueous dispersion medium, it can be suitably used.

  The organic binder preferably has a weight average molecular weight of 300 or more and 3000 or less, more preferably 400 or more and 1000 or less, and still more preferably 400 or more and 600 or less. Thereby, when the pattern formed using the conductor pattern forming ink 300 is dried, the occurrence of cracks can be more reliably prevented. On the other hand, when the weight average molecular weight of the organic binder is less than the lower limit, depending on the composition of the organic binder, the organic binder tends to be decomposed when removing the aqueous dispersion medium, thereby preventing the occurrence of cracks. The effect is reduced. When the weight average molecular weight of the organic binder exceeds the above upper limit, depending on the composition of the organic binder, the solubility and dispersibility in the conductive pattern forming ink 300 may decrease due to the excluded volume effect or the like.

  In addition, the content of the organic binder in the conductor pattern forming ink 300 is preferably 1 wt% or more and 30 wt% or less, and more preferably 5 wt% or more and 20 wt% or less. This makes it possible to more effectively prevent the occurrence of cracks and disconnections while making the ejection stability of the conductor pattern forming ink 300 particularly excellent. On the other hand, when the content of the organic binder is less than the lower limit, the effect of preventing the occurrence of cracks may be reduced depending on the composition of the organic binder. Further, when the content of the organic binder exceeds the upper limit, it may be difficult to make the viscosity of the conductor pattern forming ink 300 sufficiently low depending on the composition of the organic binder.

(Drying inhibitor)
Further, the conductor pattern forming ink 300 may contain a drying inhibitor. The drying inhibitor prevents unintended volatilization of the aqueous dispersion medium in the conductor pattern forming ink 300. As a result, the aqueous dispersion medium can be prevented from volatilizing in the vicinity of the discharge portion of the ink jet apparatus, and the increase in viscosity and drying of the conductor pattern forming ink 300 can be suppressed. As a result of including such a drying inhibitor, the conductive pattern forming ink 300 is particularly excellent in droplet ejection stability of the conductive pattern forming ink 300. That is, the variation in the weight of the droplets of the conductive pattern forming ink 300 is small, and clogging, flight bending, and the like are small. In particular, even when the ink jet device is put into a standby state without being operated for a long time (for example, 5 days) after the ink 300 for conductor pattern formation is filled in the ink jet device, the ink 300 for forming a conductor pattern is used. Can be accurately discharged to a target position in a uniform amount.
Examples of such a drying inhibitor include compounds represented by the following formula (I), alkanolamines, sugar alcohols, polysaccharides, and the like, and one or more of them can be used in combination.

（ただし、Ｒ、Ｒ’は、それぞれ、Ｈまたはアルキル基である。）

(However, R and R ′ are each H or an alkyl group.)

The compound represented by the above formula (I) is a component having a high hydrogen bonding property. For this reason, the affinity with water is high, moderate moisture can be retained, and unintentional volatilization of the aqueous dispersion medium of the conductive pattern forming ink 300 can be prevented.
Further, the compound is relatively easily combusted and can be more easily removed (oxidative decomposition) from the conductor pattern forming ink 300 when the conductor pattern 20 is formed.

In addition, when the metal particles (silver particles) are colloidal particles having a dispersant attached to the surface as described above, the compound as described above is bonded to the surface dispersant by hydrogen bonding, and the dispersion stability of the metal particles. Has the effect of improving. Accordingly, the ejection stability of the conductor pattern forming ink 300 is excellent, and the storage stability is also excellent.
As described above, R and R ′ in the compound represented by the above formula (I) used in the present invention are each hydrogen or an alkyl group, but R and R ′ are both hydrogen. preferable. That is, urea is preferable. As a result, the moisture retention as described above can be made particularly high, and particularly excellent ejection stability can be obtained. Further, when the metal particles are present as colloidal particles as described above, particularly excellent dispersion stability is exhibited.

  The content of the compound represented by the above formula (I) in the conductive pattern forming ink 300 is preferably 5 wt% or more and 25 wt% or less, and more preferably 8 wt% or more and 20 wt% or less. More preferably, it is 10 wt% or more and 18 wt% or less. Thereby, unintentional drying of the conductor pattern forming ink 300 can be prevented more efficiently. As a result, the discharge stability of the conductor pattern forming ink 300 can be made particularly excellent.

Alkanolamine is a highly moisturizing component, and when the metal particles are colloidal particles as described above, the functional group of the dispersant on the surface of the colloidal particles can be activated, and the dispersion stability of the metal particles Can be higher.
Examples of the alkanolamine include monoethanolamine, diethanolamine, triethanolamine, monopropanolamine, dipropanolamine, and tripropanolamine.

The alkanolamine is preferably a tertiary amine. Tertiary amines have particularly high moisture retention among alkanolamines, and can make the above effects more remarkable.
Among tertiary amines, it is particularly preferable to use triethanolamine from the viewpoints of ease of handling, high moisture retention, and the like.

The content of alkanolamine in the conductive pattern forming ink 300 is preferably 1 wt% or more and 10 wt% or less, more preferably 3 wt% or more and 7 wt% or less. Thereby, the ejection stability of the conductor pattern forming ink 300 can be more effectively improved.
Sugar alcohol is obtained by reducing aldehyde groups and ketone groups of sugars.

  Sugar alcohol is a compound having high moisture retention. In addition, since sugar alcohol has a large number of oxygen per molecular weight, it is easily decomposed and removed when the atmosphere reaches the decomposition temperature of sugar alcohol. For this reason, when the conductor pattern 20 is formed, the sugar alcohol is reliably removed from the formed conductor pattern 20 by oxidizing the temperature of the conductor pattern precursor 10 higher than the decomposition temperature of the sugar alcohol (oxidative decomposition). )can do.

  Examples of sugar alcohols include threitol, erythritol, pentaerythritol, dipentaerythritol, tripentaerythritol, arabitol, ribitol, xylitol, sorbitol, mannitol, threitol, glycol, tallitol, galactitol, allitol, altritol, dolitol, iditol. Glycerin (glycerol), inositol, maltitol, isomaltitol, lactitol, tranitol and the like, and one or more of these can be used in combination.

  The content of the sugar alcohol as described above in the conductor pattern forming ink 300 is preferably 3 wt% or more and 20 wt% or less, and more preferably 5 wt% or more and 15 wt% or less. Thereby, volatilization of the aqueous dispersion medium of the conductive pattern forming ink 300 can be more reliably suppressed, and the conductive pattern forming ink 300 has particularly excellent droplet ejection stability over a longer period of time.

Polysaccharide is a highly moisturizing component, and in particular, when included with the polyglycerin compound as described above, in the conductive pattern formed using the conductive pattern forming ink, unintentional cracks, disconnections, etc. Generation | occurrence | production can be prevented more reliably and the reliability of the conductor pattern formed can be made especially high.
The conductive pattern forming ink preferably contains a polysaccharide that is solid at room temperature (25 ° C.). Thereby, the reliability of the conductor pattern formed can be made especially excellent.
The weight average molecular weight of the polysaccharide is from 1,000 to 5,000, preferably from 1,200 to 4,500, and more preferably from 1,500 to 4,000. Thereby, the effects as described above are more remarkably exhibited.

  Examples of the polysaccharide include cellulose, guar gum, starch (amylose, amylopectin), pullulan, dextrin, fructan, glucomannan, agarose, agaropectin, carrageenan, chitin, chitosan, pectin, alginic acid, hyaluronic acid, maltodextrin, or these Derivatives (for example, polysaccharides in which a carbonyl group is reduced) and the like can be mentioned, and one or more of these can be used in combination. Among the above, the conductive pattern forming ink preferably contains a solid maltodextrin at room temperature (25 ° C.). Thereby, the discharge stability of the droplet and the reliability of the formed conductor pattern can be made particularly excellent.

In addition, the conductor pattern forming ink preferably contains a polysaccharide having a carbonyl group reduced as the polysaccharide. Thereby, the discharge stability of the droplet and the reliability of the formed conductor pattern can be made particularly excellent.
The content of the polysaccharide as described above in the conductor pattern forming ink 300 is preferably 1 wt% or more and 28 wt% or less, and more preferably 2.2 wt% or more and 10.5 wt% or less. Thereby, volatilization of the aqueous dispersion medium of the conductive pattern forming ink 300 can be more reliably suppressed, and the conductive pattern forming ink 300 has particularly excellent droplet ejection stability over a longer period of time.

[Surface tension modifier]
In addition, the conductor pattern forming ink 300 may contain a surface tension adjusting agent.
The surface tension adjusting agent has a function of adjusting the contact angle between the conductor pattern forming ink 300 and the ceramic molded body 15 to a predetermined angle.
As the surface tension adjusting agent, various surfactants can be used, and one or a combination of two or more types can be used, but it is preferable to include an acetylene glycol compound.

  The contact angle between the conductive pattern forming ink 300 and the ceramic molded body 15 can be adjusted within a predetermined range with a small addition amount of the acetylene glycol compound. Thus, the finer conductor pattern 20 can be formed by adjusting the contact angle between the conductor pattern forming ink 300 and the ceramic molded body 15 within a predetermined range. Further, even when bubbles are mixed in the discharged droplets, the bubbles can be quickly removed. As a result, generation of cracks and disconnections in the formed conductor pattern 20 can be more effectively prevented.

  Examples of acetylene glycol compounds include Surfynol 104 series (104E, 104H, 104PG-50, 104PA, etc.), Surfynol 400 series (420, 465, 485, etc.), Olphine series (EXP4036, EXP4001, E1010, etc.). ("Surfinol" and "Orphine" are trade names of Nissin Chemical Industry Co., Ltd.) and the like, and one or more of these can be used in combination.

The conductive pattern forming ink 300 preferably contains two or more acetylene glycol compounds having different HLB values. The contact angle between the conductor pattern forming ink 300 and the ceramic molded body 15 can be easily adjusted within a predetermined range.
In particular, among the two or more acetylene glycol compounds contained in the conductor pattern forming ink 300, the HLB value of the acetylene glycol compound having the highest HLB value and the HLB value of the acetylene glycol compound having the lowest HLB value The difference is preferably 4 or more and 12 or less, and more preferably 5 or more and 10 or less. Thereby, the contact angle between the conductor pattern forming ink 300 and the ceramic molded body 15 can be easily adjusted within a predetermined range with a smaller addition amount of the acetylene glycol compound.

In the case where the conductive pattern forming ink 300 includes two or more acetylene glycol compounds, the HLB value of the acetylene glycol compound having the highest HLB value is preferably 8 or more and 16 or less, and 9 or 14 The following is more preferable.
Moreover, when using what contains 2 or more types of acetylene glycol type compounds in the ink 300 for conductor pattern formation, it is preferable that the HLB value of the acetylene glycol type compound with the lowest HLB value is 2-7. More preferably, it is 5 or less.
The content of the surface tension adjusting agent contained in the conductor pattern forming ink 300 is preferably 0.001 wt% or more and 1 wt% or less, and more preferably 0.01 wt% or more and 0.5 wt% or less. Thereby, the contact angle between the conductor pattern forming ink 300 and the ceramic molded body 15 can be adjusted more effectively within a predetermined range.

[Other ingredients]
The constituent components of the conductor pattern forming ink 300 are not limited to the above components, and may include components other than those described above.
Examples of such components include thiourea.
The viscosity of the conductive pattern forming ink 300 is not particularly limited, but is preferably 2.0 mPa · s or more and 12.0 mPa · s or less, and preferably 5.0 mPa · s or more and 10.0 mPa · s or less. Is more preferable. As a result, the droplet ejection stability can be improved, and the unintentional wetting and spreading of the conductor pattern forming ink 300 landed on the ceramic molded body 15 can be more reliably prevented. A conductor pattern precursor 10 having a wide line width can be formed.

The conductive pattern forming ink 300 can be discharged under the same conditions using the droplet discharge device 100 as described in the polyhydric alcohol condensate application step.
In such a case, the droplet discharge device 100 has a rubber heater (not shown) disposed on the back surface of the table 140. In this step, the ceramic green sheet 15 placed on the table 140 The entire upper surface is preferably heated to a predetermined temperature with a rubber heater. As a result, the conductive pattern forming ink 300 that has landed on the ceramic molded body 15 is absorbed by the ceramic molded body 15 and at least a part of the aqueous dispersion medium, which is a constituent component, from the surface side. At least a part of the aqueous dispersion medium evaporates. At this time, since the ceramic green sheet 15 is heated, the evaporation of the aqueous dispersion medium is promoted, and the content of the aqueous dispersion medium in the layer in which the metal particles are concentrated (conductor pattern precursor 10) is effectively reduced. Is done.

The heating temperature of the ceramic green sheet 15 is preferably 40 ° C. or higher and 100 ° C. or lower, and more preferably 50 ° C. or higher and 70 ° C. or lower, for example. By setting it as such conditions, when an aqueous dispersion medium evaporates, it can prevent more effectively that a crack generate | occur | produces.
By performing this step using the ink jet apparatus 100 as described above, the conductor pattern forming ink 300 is accurately ejected to a desired location on the ceramic green sheet 15 (base S). Can do. Furthermore, since the ceramic green sheet 15 and the conductor pattern forming ink 300 as described above are used, the landing positions of the metal particles contained in the conductor pattern forming ink 300 discharged onto the ceramic green sheet 15 are as follows. Therefore, the unintentional movement can be effectively prevented, and the conductor pattern precursor 10 having a desired shape can be reliably formed.
In addition, you may perform a drying process about the formed conductor pattern precursor 10. FIG. The drying process can be performed under the same conditions as the heating temperature of the ceramic green sheet 15 at the time of droplet discharge.

  The thickness of the conductor pattern precursor 10 can be adjusted by setting the discharge conditions for the conductor pattern forming ink 300. That is, when forming a portion where the thickness of the conductor pattern precursor 10 is large, the discharge amount (or the number of droplets) of the conductor pattern forming ink 300 per area of the portion is made large. In the case where a portion where the thickness of the pattern precursor 10 is small is formed, the discharge amount (or the number of droplets) of the conductor pattern forming ink 300 per area of the portion can be reduced.

  As described above, since the ceramic green sheet (ceramic molded body) 15 includes a polyhydric alcohol condensate, the conductive pattern forming ink 300 that has landed on the ceramic green sheet 15 is an aqueous component that is a constituent component thereof. The dispersion medium (dispersion medium) is quickly absorbed by the ceramic green sheet 15. For this reason, even if the thickness of the conductor pattern precursor 10 to be formed is relatively large and the amount of the conductor pattern forming ink 300 discharged to the same region is relatively large, Excessive wetting and spreading can be prevented, and the conductor pattern precursor 10 having a smaller line width can be formed more suitably.

  Further, in the case where the drying inhibitor is included in the conductor pattern forming ink 300 after the dispersion medium is evaporated, there is no possibility that the pattern is lost even when the formed precursor 10 is not completely dried. Therefore, it is possible to apply the conductive pattern forming ink 300 once, dry and leave it for a long time, and then apply the conductive pattern forming ink 300 again.

Further, when the conductive pattern forming ink 300 includes the organic binder as described above, since the organic binder (particularly, the polyglycerin compound) is a chemically and physically stable compound, the conductive pattern forming ink 300 is used. Even if the ink is applied and dried and left for a long time, the conductor pattern forming ink 300 does not change in quality, and the conductor pattern forming ink 300 can be applied again, and a more uniform pattern can be formed. Thereby, there is no possibility that the precursor 10 itself has a multilayer structure, and as a result, there is no possibility that the specific resistance between the layers increases and the specific resistance of the entire conductor pattern 20 increases.
Through the above steps, the conductor pattern 20 of the present embodiment can be formed thicker than a conductor pattern formed by a conventional ink. More specifically, a film having a thickness of 5.5 μm or more can be formed.

(Lamination process)
Next, the PET film is peeled off from these ceramic green sheets 15 and these are laminated to obtain a laminate 17.
At this time, the ceramic green sheets 15 to be laminated are arranged so that the precursors 10 are connected via the conductor posts 16 between the ceramic green sheets 15 stacked one above the other as necessary.
Thereafter, the laminated ceramic green sheets 15 are packaged and sealed in a polyethylene pack, and then the ceramic green sheets 15 are pressure-bonded to each other while being heated above the glass transition point of the binder constituting the ceramic green sheets 15 by a hydrostatic press. To do. Thereby, the laminated body 17 is obtained.

(Baking process)
When the laminated body 17 is formed in this way, after being opened from the polyethylene pack, it is subjected to heat treatment (firing treatment) by, for example, a belt furnace. Thereby, each ceramic green sheet 15 is sintered to become a ceramic substrate 31, and the precursor 10 is composed of a wiring pattern or an electrode pattern by sintering silver particles (metal particles) constituting the ceramic substrate 31. A circuit (conductor pattern) 20 is obtained. And the laminated body 17 becomes the laminated substrate 32 by heat-processing the laminated body 17 in this way.

  In particular, since the ceramic green sheet 15 used in this step contains a polyhydric alcohol condensate and absorbs an aqueous dispersion medium (dispersion medium), the polyhydric alcohol is used in the heat treatment in this step. The condensate and the absorbed aqueous dispersion medium (dispersion medium) are gradually released to the surroundings. As a result, the conductor pattern precursor 10 provided on the ceramic green sheet 15 is prevented from drying out rapidly, and the conductor pattern 20 formed in this step is reliably prevented from being cracked. . Such an effect is more remarkably exhibited when the conductor pattern forming ink 300 contains a drying inhibitor.

  Here, the heating temperature (firing temperature) of the laminated body 17 is preferably not less than the softening point of the glass contained in the ceramic green sheet 15, and specifically, not less than 600 ° C and not more than 900 ° C. preferable. As heating conditions, the temperature is raised and lowered at an appropriate rate, and the maximum heating temperature, that is, the temperature of 600 ° C. to 900 ° C. is maintained for an appropriate time according to the temperature. To do.

  Thus, the glass component of the ceramic substrate 31 obtained can be softened by raising the heating temperature to a temperature equal to or higher than the softening point of the glass, that is, the temperature range. Therefore, after cooling to room temperature and curing the glass component, the ceramic substrate 31 constituting the laminated substrate 32 and the circuit (conductor pattern) 20 are more firmly fixed.

In particular, the ceramic substrate 31 obtained by heating at a temperature of 900 ° C. or lower becomes a low-temperature fired ceramic (LTCC).
Here, the metal particles constituting the conductor pattern precursor 10 provided on the ceramic green sheet 15 are fused to each other by heat treatment and become conductive by being continuous.

  By such heat treatment, the circuit 20 is directly connected to the contact 33 in the ceramic substrate 31 and made conductive. Here, if the circuit 20 is merely placed on the ceramic substrate 31, the mechanical connection strength to the ceramic substrate 31 is not ensured, and therefore there is a possibility that the circuit 20 may be damaged by an impact or the like. However, in this embodiment, as described above, the circuit 20 is firmly fixed to the ceramic substrate 31 by once softening the glass in the ceramic green sheet 15 and then curing it. Therefore, the formed circuit 20 has a high mechanical strength.

In such a method of manufacturing the ceramic circuit board 30, the conductive pattern forming ink 300 is applied to the ceramic green sheet 15 as described above, particularly when the ceramic substrates 31 constituting the multilayer substrate 32 are manufactured. Thus, the conductor pattern 20 having a desired shape can be reliably formed with high accuracy.
Therefore, according to the present invention, it is possible not only to meet the demand for miniaturization of electronic components that are components of electronic equipment, but also to fully meet the needs for high-mix low-volume production.

  Moreover, since the heating temperature at the time of heat-treating the ceramic green sheet 15 is set to be equal to or higher than the softening point of the glass contained in the ceramic green sheet 15, the ceramic green sheet 15 is formed when the ceramic green sheet 15 is made into the ceramic substrate 31 by heat treatment. The softened glass of the conductor pattern 20 is firmly fixed on the ceramic substrate 31 (ceramic green sheet 15), and therefore the mechanical strength of the conductor pattern 20 can be increased.

  As described above, in the present invention, a conductor pattern forming ink set including the polyhydric alcohol condensate-containing ink as described above and a conductor pattern forming ink is used for forming a conductor pattern (manufacturing a wiring board). By using it, the amount of polyhydric alcohol condensate used is suppressed, and the production cost of the wiring board is suppressed, while the occurrence of cracks, disconnections, short circuits, etc. is prevented, and reliability with a highly reliable conductor pattern is provided. A high wiring board can be provided.

<< Conductor pattern and wiring board >>
Next, the conductor pattern and wiring board obtained by using the method as described above will be described.
The wiring board (ceramic circuit board) 30 is formed on a laminated board 32 in which a large number (for example, about 10 to 20 pieces) of ceramic boards 31 are laminated, and an outermost layer of the laminated board 32, that is, a surface on one side. In addition, the circuit 20 is formed of a fine wiring or the like.

The laminated substrate 32 includes a conductor pattern (circuit) 20 formed by the conductor pattern precursor 10 between the laminated ceramic substrates 31 and 31.
The conductor pattern 20 is a thin-film conductor pattern formed by heating (sintering) the conductor pattern precursor 10 as described above, and is formed by bonding silver particles to each other, and at least the conductor pattern 20. The silver particles are bonded to each other without a gap on the surface.

The specific resistance of the conductor pattern 20 is preferably less than 20 μΩcm, and more preferably 15 μΩcm or less. The specific resistance at this time refers to the specific resistance after heating and drying at 600 ° C. to 900 ° C. after ink application. When the specific resistance is 20 μΩcm or more, it becomes difficult to use it for applications requiring electrical conductivity, that is, for electrodes formed on a circuit board.
The conductor pattern 20 as described above is used for high-frequency modules, interposers, MEMS (Micro Electro Mechanical Systems), acceleration sensors, surface acoustic wave elements, antennas, comb electrodes, and the like of mobile telephones such as mobile phones and PDAs. The present invention can be applied to deformed electrodes and other electronic parts such as various measuring devices.

In addition, a contact (via) 33 connected to the circuit 20 is formed on the ceramic substrate 31. With such a configuration, the circuit 20 is electrically connected by the contact 33 between the circuits 20 and 20 arranged above and below.
The wiring board 30 as described above is an electronic component used in various electronic devices, such as circuit patterns composed of various wirings and electrodes, multilayer ceramic capacitors, multilayer inductors, LC filters, composite high frequency components, and the like. Is formed on a substrate.
As mentioned above, although this invention was demonstrated based on suitable embodiment, this invention is not limited to these.

For example, in the above-described embodiment, the case where a colloidal liquid is used as the conductor pattern forming ink has been representatively described.
In the above-described embodiment, the conductor pattern forming ink is described as having silver particles dispersed therein, but may be other than silver. As a metal which comprises a metal particle, silver, copper, palladium, platinum, gold | metal | money, or these alloys etc. are mentioned, for example, These can be used 1 type or in combination of 2 or more types. When the metal particles are an alloy, the metal is mainly used, and an alloy containing another metal may be used. Moreover, the alloy which the said metals mixed with arbitrary ratios may be sufficient. Further, mixed particles (for example, particles in which silver particles, copper particles, and palladium particles are present in an arbitrary ratio) may be dispersed in a liquid. Since these metals have a low resistivity and are stable and are not oxidized by heat treatment, it is possible to form a stable conductor pattern with a low resistance by using these metals.

Further, in the above-described embodiment, the case where the conductive pattern forming ink includes an aqueous dispersion medium as a dispersion medium for dispersing the metal particles has been representatively described. However, as the dispersion medium, water and / or a phase with water is used. A non-aqueous dispersion medium (oil-based dispersion medium) that is a liquid having poor solubility (for example, a liquid having a solubility in 100 g of water at 25 ° C. of less than 30 g) may be included.
Further, for example, in the above-described embodiment, the piezo method is used as the droplet discharge method. However, the present invention is not limited to this, and for example, a method of discharging ink by bubbles generated by heating the ink is known. Various techniques can be applied.

Next, specific examples of the present invention will be described.
Example 1
[1] Production of Temporary Molding First, alumina (Al ₂ O ₃ ) powder having an average particle size of 1.5 μm as ceramic powder and titanium oxide (TiO ₂ ) having an average particle size of 1.5 μm as ceramic powder. The powder and a borosilicate glass powder having an average particle size of 1.5 μm as a glass powder were mixed to obtain a mixed powder.

Next, a slurry was obtained by adding polyvinyl butyral as a binder (binder) and dibutyl phthalate as a plasticizer to the mixed powder, and mixing and stirring.
Next, the slurry was formed into a sheet shape on a PET film with a doctor blade, and this was cut into a square shape having a side length of 200 mm, thereby obtaining a large number of temporary molded bodies.

[2] Preparation of conductive pattern forming ink set [2-1] Preparation of polyhydric alcohol condensate-containing ink Polyglycerin (weight average molecular weight: 500) and polyethylene glycol (weight average molecular weight: 400) as polyhydric alcohol condensate ), Water, and olefin E1010 as a surfactant were mixed to obtain a polyhydric alcohol condensate-containing ink.

[2-2] Preparation of Ink for Conductive Pattern Formation 17 g of trisodium citrate dihydrate and 0.36 g of tannic acid were dissolved in 50 mL of water made alkaline by adding 3 mL of 10N-NaOH aqueous solution. To the obtained solution, 3 mL of 3.87 mol / L silver nitrate aqueous solution was added and stirred for 2 hours to obtain a silver colloid solution. The obtained silver colloid solution was desalted by dialysis until the electrical conductivity was 30 μS / cm or less. After dialysis, the coarse metal colloid particles were removed by centrifugation at 3000 rpm for 10 minutes.

In this silver colloid liquid, triethanolamine as a drying inhibitor, urea, xylitol, polyglycerin as an organic binder, Surfynol 104PG-50 (manufactured by Nissin Chemical Industry Co., Ltd.) as a surface tension adjusting agent, and Orfin EXP4036 (manufactured by Nissin Chemical Industry Co., Ltd.) was added, and ion exchange water for concentration adjustment was further added to obtain a conductor pattern forming ink.
As a result, a conductor pattern forming ink set comprising the polyhydric alcohol condensate-containing ink and the conductor pattern forming ink was obtained.

[3] Manufacture of Ceramic Circuit Board Using the conductive pattern forming ink set and the temporary molded body obtained as described above, a ceramic circuit board was manufactured as follows.
First, the polyhydric alcohol condensate-containing ink was mounted on a droplet discharge device as shown in FIGS. Next, droplets of polyhydric alcohol condensate-containing ink were sequentially discharged from the discharge nozzles of the droplet discharge device toward the temporary molded body to obtain a ceramic green sheet (ceramic molded body) (polyhydric alcohol). Condensate application step). The provision of the polyhydric alcohol condensate-containing ink to the temporary molded body is carried out with a pattern corresponding to the conductor pattern precursor to be formed using the conductor pattern forming ink on the side on which the conductor pattern is formed, and on the opposite side. On the surface, a pattern corresponding to the conductor pattern precursor on the adjacent ceramic green sheet when the laminate was formed was performed.

Next, the ceramic green sheet (ceramic molded body) placed on the table of the ink jet apparatus as shown in FIGS. 2 and 3 loaded with the conductive pattern forming ink was heated to 60 ° C. and held. Thereafter, 15 ng droplets per droplet were sequentially discharged from each discharge nozzle, and 20 lines (precursors) having a line width of 50 μm, a thickness of 20 μm, and a length of 10.0 cm were drawn. The distance between each line was 5 mm. And the ceramic green sheet in which this line was formed was put into the drying furnace, and it heated and dried at 60 degreeC for 30 minutes (conductor pattern precursor formation process).
The ceramic green sheet on which the line was formed as described above was used as the first ceramic green sheet. Two sheets of the first ceramic green sheet were produced.

  Next, through holes with 100 μm in diameter are formed in a total of 40 locations by punching another ceramic green sheet with mechanical punches or the like at both ends of the above metal wiring, and filling with a conductive pattern forming ink. A contact (via) was formed. Further, a 2 mm square pattern was formed on this contact (via) as a terminal portion by discharging the conductor pattern forming ink using the droplet discharge device.

The ceramic green sheet on which this terminal portion was formed was used as the second ceramic green sheet.
Next, two first ceramic green sheets are laminated, two first ceramic green sheets laminated under the second ceramic green sheet, and a non-processed ceramic green sheet as a reinforcing layer. Were stacked, and then pressed at a pressure of 260 kg / cm ² for 30 minutes at a temperature of 95 ° C. to obtain a raw laminate (lamination step). Twenty such raw laminates were produced.
Next, in the atmosphere, the temperature is increased continuously at a temperature rising rate of 66 ° C./hour for about 6 hours, a temperature rising rate of 10 ° C./hour for about 5 hours, and a temperature rising rate of 85 ° C./hour for about 4 hours. Through a temperature process, sintering was performed according to a sintering profile of holding at a maximum temperature of 890 ° C. for 30 minutes to obtain a ceramic circuit board (firing process).

(Examples 2 to 12)
A polyhydric alcohol condensate-containing ink having a composition as shown in Table 1 is used, a conductor pattern forming ink having a composition as shown in Table 1 is used, and a temporary molded article having a composition as shown in Table 1 is used. A ceramic circuit board was manufactured in the same manner as in Example 1 except that it was used.

(Comparative Example 1)
A ceramic circuit board was produced in the same manner as in the above example except that the polyhydric alcohol condensate application step was omitted.
(Comparative Example 2)
A ceramic circuit board was produced in the same manner as in Example 1 except that the polyhydric alcohol condensate-containing ink was applied only to the surface on the side where the conductor pattern was to be formed.

  For each of the examples and comparative examples, the blending amount of each constituent material of the polyhydric alcohol condensate-containing ink is shown in Table 1, the blending amount of each constituent material of the temporary molded body is shown in Table 2, and the conductor pattern forming ink The amount of each constituent material is shown in Table 3. For Comparative Example 2, the ink conditions used in place of the polyhydric alcohol condensate-containing ink are shown in Table 1. In the table, polyglycerol is PG, polyethylene glycol is PEG, triethanolamine is TEA, monoethanolamine is MEA, diethanolamine is DEA, urea is Ur, xylitol is Xyl, maltodextrin is Mds, and reduced maltodextrin is Rmd. Indicated. In addition, the viscosity of the polyhydric alcohol condensate-containing ink in each of the above Examples (viscosity at 25 ° C. measured according to JIS Z8809 using a vibration viscometer) is 5.0 mPa · s. The value was in the range of 10.0 mPa · s or less. In addition, the viscosity of the conductive pattern forming ink for each of the above Examples (viscosity at 25 ° C. measured according to JIS Z8809 using a vibration viscometer) is 5.0 mPa · s or more and 10. The value was within the range of 0 mPa · s or less.

[4] Evaluation of ceramic circuit board (conductivity reliability)
For the ceramic circuit boards obtained in each of the above examples and comparative examples, a tester was applied between the terminal portions formed on the 20 conductor patterns to check whether or not each of the 20 conductor patterns was conductive. Was confirmed to be non-defective when the conductivity was 100%. The conductivity for each ceramic circuit board is obtained by dividing the number of conductive patterns (X) with conduction by the number of formed conductive patterns (20) ((X / 20) × 100 [%]) The sintering stability was evaluated according to the following evaluation criteria.

A: The conductivity was 100% in all 20 ceramic circuit boards.
B: There were 15 or more ceramic circuit boards having a conductivity of 100%, and other ceramic circuit boards also had a conductivity of 95% or more.
C: There were 10 to 14 ceramic circuit boards having a conductivity of 100%, and other ceramic circuit boards also had a conductivity of 95% or more.
D: There were 5 to 9 ceramic circuit boards having a conductivity of 100%, and other ceramic circuit boards also had a conductivity of 95% or more.
E: There were 1 to 4 ceramic circuit boards having a conductivity of 100%, and other ceramic circuit boards also had a conductivity of 95% or more.
F: Conductivity was 95% or more and less than 100% in all 20 ceramic circuit boards.
G: Conductivity was less than 95% in all 20 ceramic circuit boards.

[5] Line width stability of conductor pattern Using the polyhydric alcohol condensate-containing ink, conductor pattern forming ink, and temporary molding according to each of the above examples, the line width stability of the conductor pattern is as follows. Was evaluated.
First, using a polyhydric alcohol condensate-containing ink, a line having a line width of 90 μm and a length of 10.0 cm is spaced by 45 μm at a designed value after drawing on a temporary molded body by a droplet discharge method. Five lines were drawn to form a polyhydric alcohol condensate-containing part to obtain a ceramic green sheet.

  Next, by using a conductive pattern forming ink, a line width of 90 μm, a thickness of 20 μm, and a length of the designed values after drawing are applied by a droplet discharge method so as to overlap the polyhydric alcohol condensate-containing part of the ceramic green sheet. 5 lines (conductor pattern precursor) of 10.0 cm were drawn at 45 μm intervals to form films, and the line width (Y μm) of each line was measured with a laser microscope.

Thereafter, the ceramic green sheets on which the film was formed were laminated under the same conditions as described above to obtain a laminate before sintering.
After immersing the above laminate in liquid nitrogen for 1 minute and freezing, it is broken by cutting glass in the direction perpendicular to the line, SEM observation is performed to check for shorts and to measure the line width (Zμm). did. In each line, the deformation ratio of the line width was determined as ((Z−Y) / Y [%]), and the line width stability was evaluated according to the following evaluation criteria.

For Comparative Example 1, a laminate was obtained in the same manner as above except that the step of applying the polyhydric alcohol condensate-containing ink was omitted, and evaluation was performed in the same manner as described above.
For Comparative Example 2, a laminated body was obtained in the same manner as described above except that the ink containing glycerin was used instead of the polyhydric alcohol condensate, instead of the polyhydric alcohol condensate-containing ink. Evaluation was performed in the same manner as above.

A: The deformation rate of the most crushed wiring was less than 10%.
B: The deformation rate of the most crushed wiring was less than 20%.
C: The deformation rate of the most crushed wiring was less than 40%.
D: Even a part is in contact (short circuit) between adjacent parts.
These results are shown in Table 4.

  As apparent from Table 4, in the present invention, the ceramic circuit board showed excellent conductivity. In addition, the conductor pattern had high line width stability and particularly high reliability. On the other hand, in the comparative example, a satisfactory result was not obtained. In addition, it was confirmed that voids were generated in the ceramic circuit board of the comparative example.

  DESCRIPTION OF SYMBOLS 10 ... Conductor pattern precursor (precursor) 13 ... Polyhydric alcohol condensate containing part 14 ... Temporary molded object 15 ... Ceramic green sheet (ceramic molded object) 16 ... Conductor post (contact precursor) 17 ... Laminate 19 ... Many Non-hydric alcohol condensate-containing part 20 ... Conductor pattern (circuit) 30 ... Ceramic circuit board (wiring board) 31 ... Ceramic substrate 32 ... Multilayer substrate 33 ... Contact 100 ... Inkjet device (droplet ejection device) 110 ... Inkjet head (liquid) 111: Head body 112 ... Vibration plate 113 ... Piezo element 114 ... Body 115 ... Nozzle plate 115P ... Ink ejection surface 116 ... Reservoir 117 ... Ink chamber 118 ... Nozzle (protruding part) 130 ... Base 140 ... Table 170 ... The Positioning means 171 ... first moving means 172 ... motor 180 ... head positioning means 181 ... second moving means 182 ... linear motors 183, 184, 185 ... motor 190 ... control device 191 ... driving circuit 200 ... containing polyhydric alcohol condensate Composition (polyhydric alcohol condensate-containing ink) 300 ... Ink for forming a conductor pattern S ... Base material

Claims (12)

A temporary molded body preparation step of preparing a sheet-shaped temporary molded body made of a material containing a ceramic material and a binder;
By applying a composition containing a polyhydric alcohol condensate to both surfaces of the temporary molded body, a polyhydric alcohol condensation is obtained in which a ceramic molded body in which a region containing the polyhydric alcohol condensate is formed near the surface is formed. An object imparting step;
Conductive pattern forming ink containing metal particles and a dispersion medium in which the metal particles are dispersed is ejected to a region containing the polyhydric alcohol condensate of the ceramic molded body by a droplet discharge method, thereby forming a conductor pattern precursor. A conductor pattern precursor forming step of forming
A laminating step of laminating a plurality of the ceramic molded bodies to obtain a laminated body;
A method of manufacturing a wiring board, comprising: sintering the laminated body to obtain a wiring board having a conductor pattern and a ceramic substrate.   The composition containing the polyhydric alcohol condensate is selectively applied to a region to which the conductive pattern forming ink is applied and a region in contact with the conductive pattern precursor of the adjacent ceramic molded body in the laminate. The method for manufacturing a wiring board according to claim 1, which is applied.   The method for manufacturing a wiring board according to claim 1, wherein the composition containing the polyhydric alcohol condensate is applied by a droplet discharge method.   The method for manufacturing a wiring board according to claim 1, wherein the polyhydric alcohol condensate has a weight average molecular weight of 4000 or less.   5. The method for manufacturing a wiring board according to claim 1, wherein the composition contains a condensate of ethylene glycol and / or glycerin as the polyhydric alcohol condensate.   The method for producing a wiring board according to claim 5, wherein the composition contains polyethylene glycol and polyglycerin as a condensate of the polyhydric alcohol. When the content of polyethylene glycol in the composition is X _PEG [wt%] and the content of polyglycerin in the composition is X _PG [wt%], 0.10 ≦ X _PEG / X _PG ≦ 0 The method of manufacturing a wiring board according to claim 6, wherein the relation of .70 is satisfied.   The method for manufacturing a wiring board according to claim 1, wherein the ceramic molded body contains polyvinyl butyral as the binder.   The method for manufacturing a wiring board according to claim 1, wherein the ceramic molded body contains an acrylic resin as the binder.   The method for manufacturing a wiring board according to claim 1, wherein the conductive pattern forming ink contains a polyglycerin compound.   The method for manufacturing a wiring board according to claim 1, wherein the conductive pattern forming ink contains an aqueous dispersion medium as the dispersion medium.   A wiring board manufactured using the method according to claim 1.

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