WO2017163615A1

WO2017163615A1 - Binder resin for electroconductive composition, composition containing same for electroconductive pattern formation, and polyurethane

Info

Publication number: WO2017163615A1
Application number: PCT/JP2017/003343
Authority: WO
Inventors: 周平米田; 内田　博
Original assignee: 昭和電工株式会社
Priority date: 2016-03-23
Filing date: 2017-01-31
Publication date: 2017-09-28
Also published as: KR20180107283A; CN109071938A; JPWO2017163615A1; TW201805323A; KR102121758B1; CN109071938B; JP6994455B2; TWI774658B

Abstract

[Problem] To provide: a binder resin for electroconductive compositions which, with lower sintering energy, give electroconductive patterns having improved electroconductivity; a composition for electroconductive pattern formation which contains the binder resin; and a polyurethane. [Solution] The binder resin for electroconductive compositions comprises a polyurethane having, in the polymer skeleton, a metal carboxylate moiety represented by (COO)_nM (where M is the atom of a metal selected from the metals belonging to Group 11 of the periodic table and n is the valence of the metal atom M). The binder resin for electroconductive compositions is mixed with an electroconductive material and a solvent in which the binder resin for electroconductive compositions dissolves, thereby giving a composition for electroconductive pattern formation which attains improved electroconductivity with low sintering energy.

Description

Binder resin for conductive composition, conductive pattern forming composition containing the same, and polyurethane

The present invention relates to a binder resin for a conductive composition, a composition for forming a conductive pattern including the binder resin, and polyurethane.

As a technique for producing a fine wiring pattern, a method of forming a wiring pattern by a lithography method using a combination of a copper foil and a photoresist is generally used, but this method has many processes, drainage, The burden of waste liquid treatment is large, and environmental improvement is desired. Also known is a method of patterning a metal thin film produced by a heat deposition method or a sputtering method by a photolithography method. However, the heating vapor deposition method and the sputtering method are indispensable for a vacuum environment, and the price is very expensive. When applied to a wiring pattern, it is difficult to reduce the manufacturing cost.

Therefore, a technique for producing a wiring by printing using an ink containing a metal or a metal oxide has been proposed. Since the wiring technology by printing is capable of producing a large quantity of products at low cost and at high speed, the production of practical electronic devices has already been studied in part.

For example, the following Patent Document 1 discloses a step of discharging a conductive inorganic composition containing conductive inorganic metal particles on a substrate, and a conductive organic composition containing a conductive organometallic complex on the conductive inorganic composition. A method for manufacturing a substrate is disclosed which includes a step of discharging the conductive inorganic composition and the conductive organic composition.

However, the method of heating and baking ink containing metal using a heating furnace takes time in the heating process, and if the plastic substrate cannot withstand the heating temperature, it reaches a satisfactory conductivity. There was a problem of not doing.

Moreover, in the said patent document 1, it was necessary to discharge a conductive inorganic composition and a conductive organic composition separately, and there also existed a problem that a process was complicated.

Therefore, as described in Patent Documents 2 to 6, it is conceivable to use a conductive composition (ink) containing nanoparticles and convert it to metal wiring by light irradiation.

The method of using light energy or microwaves for heating can be said to be a very good method because it may heat only the ink portion.

However, in order to obtain a desired conductivity, high energy light irradiation may be required. In this case, the substrate may not be able to withstand the energy as in the case of firing in a heating furnace.

JP 2010-183082 A Special table 2008-522369 Pamphlet of WO2010 / 110969 Special table 2010-528428 Pamphlet of WO2013 / 077447 WO2015 / 064567 pamphlet

In general, the conductive pattern formed on the substrate is more desirable as the electrical conductivity is higher (the volume resistivity is lower). However, the lower the sintering energy for reaching the same electrical conductivity is, the lower the electrical conductivity for forming the conductive pattern is. The composition can be said to have high performance. Therefore, it is desirable that the above-described conventional conductive composition also improve the conductivity with a lower sintering energy.

An object of the present invention is to provide a binder resin for a conductive composition capable of improving the conductivity of a conductive pattern with a low sintering energy, a composition for forming a conductive pattern and a polyurethane containing the binder resin.

In order to achieve the above object, an embodiment of the present invention is a binder resin for a conductive composition, wherein the binder resin is a carboxylate metal salt moiety represented by (COO) _n M in a polymer skeleton. It includes a polyurethane having (M is a metal atom selected from metals belonging to Group 11 of the periodic table, and n is a valence of the metal atom M).

It is preferable that the polyurethane includes a urethane bond unit of (a1) a polyisocyanate compound and (a2) a dihydroxy compound having a carboxyl group as a structural unit.

Moreover, it is preferable that the metal constituting the metal salt contains either silver or copper.

The (a2) carboxyl group-containing dihydroxy compound is preferably at least one of 2,2-dimethylolpropionic acid and 2,2-dimethylolbutanoic acid.

The (a1) polyisocyanate compound is preferably an alicyclic polyisocyanate, and the alicyclic polyisocyanate is 3-isocyanate methyl-3,3,5-trimethylcyclohexane (IPDI, isophorone diisocyanate), Alternatively, bis- (4-isocyanatocyclohexyl) methane (hydrogenated MDI) is more preferable.

Moreover, other embodiment of this invention is a composition for conductive pattern formation, Comprising: The said binder resin for conductive compositions (A), a conductive material (B), and the said binder resin for conductive compositions are included. And a solvent (C) that dissolves. As the conductive material (B), metal particles (B1), metal nanowires and / or metal nanotubes (B2) can be used.

When the metal particles (B1) are used as the conductive material (B), the ratio of the metal particles (B1) to the entire conductive pattern forming composition is 20% by mass to 95% by mass, and the binder resin for the conductive composition is dissolved. The content of the solvent (C) is 5 mass% to 80 mass%, and the binder resin for conductive composition (A) is 1 mass part to 15 mass parts with respect to 100 mass parts of the metal particles (B1). Is preferred.

When metal nanowires and / or metal nanotubes (B2) are used as the conductive material (B), the ratio of metal nanowires and / or metal nanotubes (B2) to the entire conductive pattern forming composition is 0.01% by mass to 10%. The content of the solvent (C) for dissolving the binder resin for conductive composition is 90% by mass or more, and the binder resin for conductive composition (A) is a metal nanowire and / or metal nanotube (B2) 100. The amount is preferably 10 to 400 parts by mass with respect to parts by mass.

The metal constituting the conductive material (B) preferably contains either silver or copper.

Another embodiment of the present invention is a polyurethane containing at least one of the structural units represented by the following formula (1).

According to the present invention, the conductivity of the conductive pattern can be improved with a lower sintering energy than when a binder resin containing no metal atom is used in the polymer skeleton.

FIG. 3 is a graph showing the results of simultaneous differential thermal-thermogravimetric measurement of polyurethane silver salt (using silver nitrate) according to Example 1. It is a figure which shows the differential thermal-thermogravimetric simultaneous measurement result of the polyurethane silver salt (use silver oxide) concerning Example 2. FIG. It is a figure which shows the measurement result of the infrared rays (IR) absorption spectrum of the polyurethane synthesize | combined in the synthesis example 1. FIG. It is a figure which shows the measurement result of IR absorption spectrum of the polyurethane silver salt concerning Example 1. FIG. It is a figure which shows the measurement result of the nuclear magnetic resonance (NMR) spectrum of the polyurethane synthesize | combined in the synthesis example 1. FIG. It is a figure which shows the measurement result of the NMR spectrum of the polyurethane silver salt concerning Example 1. FIG. It is a figure which shows the differential thermal-thermogravimetric simultaneous measurement result of the polyurethane copper salt (use copper sulfate) concerning Example 3. FIG. It is a figure which shows the measurement result of IR absorption spectrum of the polyurethane copper salt concerning Example 3. FIG. It is a figure which shows the differential thermal-thermogravimetric simultaneous measurement result of the polyurethane silver salt (using silver nitrate) concerning Example 4. It is a figure which shows the differential thermal-thermogravimetric simultaneous measurement result of the polyurethane silver salt (use silver oxide) concerning Example 5. FIG. It is a figure which shows the differential thermal-thermogravimetric simultaneous measurement result of the polyurethane silver salt (use silver nitrate) concerning Example 6. FIG. It is a figure which shows the differential thermal-thermogravimetric simultaneous measurement result of the polyurethane silver salt (use silver nitrate) concerning Example 7. FIG. It is a figure which shows the differential thermal-thermogravimetric simultaneous measurement result of the polyurethane silver salt (using silver nitrate) concerning Example 8. It is a figure which shows the differential thermal-thermogravimetric simultaneous measurement result of the polyurethane silver salt (using silver oxide) concerning Example 9. FIG. It is a figure which shows the differential thermal-thermogravimetric simultaneous measurement result of the polyurethane silver salt (uses silver oxide) concerning Example 10. FIG. It is a figure which shows the differential thermal-thermogravimetric simultaneous measurement result of the polyurethane silver salt (use silver oxide) concerning Example 11. FIG. It is a figure which shows the differential thermal-thermogravimetric simultaneous measurement result of the polyurethane silver salt (uses silver oxide) concerning Example 12. It is a figure which shows the differential thermal-thermogravimetric simultaneous measurement result of the polyurethane silver salt (using silver oxide) concerning Example 13. It is a figure which shows the differential thermal-thermogravimetric simultaneous measurement result of the polyurethane silver salt (using silver oxide) concerning Example 14. FIG. It is a figure which shows the differential thermal-thermogravimetric simultaneous measurement result of the polyurethane copper salt (using copper hydroxide) concerning Example 16.

Hereinafter, modes for carrying out the present invention (hereinafter referred to as embodiments) will be described.

The binder resin for a conductive composition according to the present embodiment is a metal atom selected from metals belonging to Group 11 of the periodic table, wherein the carboxylate metal salt moiety represented by (COO) _n M in the polymer skeleton. , N includes a polyurethane having a valence of a metal atom M).

The polyurethane of this embodiment includes a urethane bond unit of at least a polyisocyanate compound and a dihydroxy compound having a carboxyl group in a structural unit. A urethane bond unit between a polyisocyanate compound and a polyol other than a dihydroxy compound having a carboxyl group can be included. That is, it may be a polyurethane resin obtained by mixing (a1) a polyisocyanate compound and (a2) a dihydroxy compound having a carboxyl group with (a3) a polyol compound other than (a2) as required. . By reacting a carboxyl group (COOH group) in the obtained polyurethane resin with a compound containing a metal atom M belonging to Group 11 of the periodic table, (COO) _n M (n is the value of the metal atom M) in the polyurethane skeleton. It is possible to obtain a polyurethane resin having a carboxylic acid metal salt moiety represented by

Hereinafter, each component used for manufacturing the polyurethane resin contained in the binder resin of the present embodiment will be described in more detail.

(A1) Polyisocyanate Compound (a1) As the polyisocyanate compound, diisocyanate having two isocyanate groups per molecule is usually used. Examples of the polyisocyanate compound include aliphatic polyisocyanate, alicyclic polyisocyanate, aromatic polyisocyanate, and araliphatic polyisocyanate. A small amount of polyisocyanate having 3 or more isocyanate groups such as triphenylmethane triisocyanate can be used as long as the polyurethane containing carboxyl groups does not gel. An alicyclic polyisocyanate is preferred in that it has less yellowing.

Examples of the aliphatic polyisocyanate include 1,3-trimethylene diisocyanate, 1,4-tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate, 1,9-nonamethylene diisocyanate, 1,10-decamethylene diisocyanate, 2 2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, 2,2′-diethyl ether diisocyanate, dimer acid diisocyanate and the like.

Examples of the alicyclic polyisocyanate include 1,4-cyclohexane diisocyanate, 1,3-bis (isocyanate methyl) cyclohexane, 1,4-bis (isocyanate methyl) cyclohexane, 3-isocyanate methyl-3,3,5- Examples thereof include trimethylcyclohexane (IPDI, isophorone diisocyanate), bis- (4-isocyanatocyclohexyl) methane (hydrogenated MDI), hydrogenated (1,3- or 1,4-) xylylene diisocyanate, norbornane diisocyanate, and the like.

Examples of the aromatic polyisocyanate include 2,4′-diphenylmethane diisocyanate, 4,4′-diphenylmethane diisocyanate, 1,4-phenylene diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, (1 , 2,1,3 or 1,4) -xylene diisocyanate, 3,3′-dimethyl-4,4′-diisocyanate biphenyl, 3,3′-dimethyl-4,4′-diisocyanate diphenylmethane, 1,5- Examples thereof include naphthylene diisocyanate, 4,4′-diphenyl ether diisocyanate, and tetrachlorophenylene diisocyanate.

Examples of the araliphatic polyisocyanate include 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, α, α, α ′, α′-tetramethylxylylene diisocyanate, and 3,3′-methylene ditolylene. -4,4'-diisocyanate and the like.

These diisocyanates can be used singly or in combination of two or more. Among these, 3-isocyanate methyl-3,3,5-trimethylcyclohexane (IPDI, isophorone diisocyanate), bis- (4-isocyanatocyclohexyl) methane (hydrogenated MDI) and the like are preferable from the viewpoint of industrial availability.

(A2) Dihydroxy compound having a carboxyl group (a2) The dihydroxy compound having a carboxyl group has a molecular weight of 200 or less having either a hydroxy group or two selected from a hydroxyalkyl group having 1 or 2 carbon atoms. Carboxylic acid or aminocarboxylic acid is preferable in that the crosslinking point can be controlled. Specific examples include 2,2-dimethylolpropionic acid, 2,2-dimethylolbutanoic acid, N, N-bishydroxyethylglycine, N, N-bishydroxyethylalanine, and the like. In view of solubility, 2,2-dimethylolpropionic acid and 2,2-dimethylolbutanoic acid are particularly preferred. These (a2) dihydroxy compounds having a carboxyl group can be used singly or in combination of two or more.

(A3) Polyol compound The number average of (a3) polyol compound (however, (a3) polyol compound does not include the above-mentioned (a2) dihydroxy compound having a carboxyl group) that can be used in combination as needed. The molecular weight is usually 250 to 50,000, preferably 400 to 10,000, more preferably 500 to 5,000. This molecular weight is a value in terms of polystyrene measured by GPC under the conditions described later. When the number average molecular weight is 50,000 or less, the solubility in a solvent is high, and the viscosity becomes an appropriate viscosity even after dissolution, which is preferable in terms of easy use.

(A3) The polyol compound is, for example, a polycarbonate polyol, a polyether polyol, a polyester polyol, a polylactone polyol, a polybutadiene polyol, a hydroxylated polysilicon at both ends, and an oxygen atom only in the hydroxyl group and having 18 to 72 carbon atoms. It is a polyol compound.

The polycarbonate polyol can be obtained by reacting a diol having 3 to 18 carbon atoms with a carbonate or phosgene as a raw material, and is represented by the following structural formula (2), for example.

In the formula (2), R ¹ is a residue obtained by removing a hydroxyl group from the corresponding diol (HO—R ¹ —OH), and n ₁ is a positive integer, preferably 2 to 50. When n ₁ is 50 or less, deterioration of solubility due to excessive increase in molecular weight can be suppressed.

Specifically, the polycarbonate polyol represented by the formula (2) includes 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 3-methyl-1 , 5-pentanediol, 1,8-octanediol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, 1,9-nonanediol, 2-methyl-1,8-octanediol, 1,10 It can be produced by using decamethylene glycol or 1,2-tetradecanediol as a raw material.

The polycarbonate polyol may be a polycarbonate polyol having a plurality of types of alkylene groups in its skeleton (copolymerized polycarbonate polyol). The use of copolymerized polycarbonate polyol is often advantageous from the viewpoint of preventing crystallization of polyurethane having a carboxyl group. In consideration of solubility in a solvent, it is preferable to use a polycarbonate polyol having a branched skeleton and having a hydroxyl group at the end of the branched chain.

The polyether polyol is obtained by dehydration condensation of a diol having 2 to 12 carbon atoms or ring-opening polymerization of an oxirane compound, oxetane compound or tetrahydrofuran compound having 2 to 12 carbon atoms. It is represented by the structural formula (3).

In the formula (3), R ² is a residue obtained by removing a hydroxyl group from the corresponding diol (HO—R ² —OH), and n ₂ is a positive integer, preferably 4 to 50. The above diols having 2 to 12 carbon atoms can be used alone to form a homopolymer, or a combination of two or more can be used as a copolymer. When n ₂ is 50 or less, deterioration of solubility due to excessive increase in molecular weight can be suppressed.

Specific examples of the polyether polyol represented by the above formula (3) include polyethylene glycol, polypropylene glycol, poly-1,2-butylene glycol, polytetramethylene glycol (poly 1,4-butanediol), poly Examples include polyalkylene glycols such as -3-methyltetramethylene glycol and polyneopentyl glycol. Further, for the purpose of improving the compatibility of (polyether polyol) and the hydrophobicity of (polyether polyol), these copolymers such as 1,4-butanediol-neopentyl glycol can also be used.

The polyester polyol is obtained by dehydration condensation of a dicarboxylic acid and a diol or an ester exchange reaction between an esterified product of a lower alcohol of a dicarboxylic acid and a diol, and is represented by the following structural formula (4), for example. .

In the formula (4), R ³ is a residue obtained by removing the hydroxyl group from the corresponding diol (HO—R ³ —OH), and R ⁴ represents two carboxyl groups from the corresponding dicarboxylic acid (HOCO—R ⁴ —COOH). And n ₃ is a positive integer, preferably 2 to 50. When n ₃ is 50 or less, deterioration of solubility due to excessive increase in molecular weight can be suppressed.

Specific examples of the diol (HO—R ³ —OH) include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, , 4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, 1,8-octanediol, 1,3-cyclohexanedimethanol, 1,4- Cyclohexanedimethanol, 1,9-nonanediol, 2-methyl-1,8-octanediol, 1,10-decamethylene glycol or 1,2-tetradecanediol, 2,4-diethyl-1,5-pentanediol, Butylethylpropanediol, 1,3-cyclohexanedimethanol, 3-xylylene glycol, 1,4-xylylene Glycol, diethylene glycol, triethylene glycol, dipropylene glycol, and the like.

Specific examples of the dicarboxylic acid (HOCO-R ⁴ -COOH) include succinic acid, glutaric acid, adipic acid, azelaic acid, sebacic acid, decanedicarboxylic acid, brassic acid, 1,4-cyclohexanedicarboxylic acid, hexa Hydrophthalic acid, methyltetrahydrophthalic acid, endomethylenetetrahydrophthalic acid, methylendomethylenetetrahydrophthalic acid, chlorendic acid, fumaric acid, maleic acid, itaconic acid, citraconic acid, phthalic acid, isophthalic acid, terephthalic acid, 1,4- And naphthalenedicarboxylic acid and 2,6-naphthalenedicarboxylic acid.

The polylactone polyol is obtained by a condensation reaction of a lactone ring-opening polymer and a diol, or a condensation reaction of a diol and a hydroxyalkanoic acid, and is represented, for example, by the following structural formula (5).

In the formula (5), R ⁵ is a residue obtained by removing a hydroxyl group and a carboxyl group from the corresponding hydroxyalkanoic acid (HO—R ⁵ —COOH), and R ⁶ is a corresponding diol (HO—R ⁶ —OH). It is a residue excluding a hydroxyl group, and n ₄ is a positive integer, preferably 2 to 50. When n ₄ is 50 or less, deterioration in solubility due to excessive increase in molecular weight can be suppressed.

Specific examples of the hydroxyalkanoic acid (HO—R ⁵ —COOH) include 3-hydroxybutanoic acid, 4-hydroxypentanoic acid, and 5-hydroxyhexanoic acid.

The polybutadiene polyol is, for example, a diol obtained by polymerizing butadiene or isoprene by anionic polymerization and introducing hydroxyl groups at both ends by terminal treatment, and a diol obtained by hydrogen reduction of these double bonds.

Specific examples of the polybutadiene polyol include hydroxylated polybutadiene mainly having 1,4-repeating units (for example, Poly bd R-45HT, Poly bd R-15HT (manufactured by Idemitsu Kosan Co., Ltd.)), hydroxylated hydrogenation Polybutadiene (for example, Polytail (registered trademark) H, Polytail (registered trademark) HA (manufactured by Mitsubishi Chemical Corporation)), hydroxylated polybutadiene having mainly 1,2-repeating units (for example, G-1000, G-2000, G-3000 (manufactured by Nippon Soda Co., Ltd.)), hydroxylated hydrogenated polybutadiene (for example, GI-1000, GI-2000, GI-3000 (manufactured by Nippon Soda Co., Ltd.)), hydroxylated polyisoprene (for example, Poly IP ( Idemitsu Kosan Co., Ltd.)), hydroxylated hydrogenated polyisoprene (TATO) If, EPOL (registered trademark, manufactured by Idemitsu Kosan Co., Ltd.)), and the like.

The above-mentioned both-end hydroxylated polysilicone is represented by the following structural formula (6), for example.

In the formula (6), R ⁷ is independently an aliphatic hydrocarbon divalent residue or an aromatic hydrocarbon divalent residue having 2 to 50 carbon atoms, and n ₅ is a positive integer, preferably 2 to 50 It is. These may contain an ether group, and the plurality of R ⁸ are each independently an aliphatic hydrocarbon group or an aromatic hydrocarbon group having 1 to 12 carbon atoms. When n ₅ is 50 or less, deterioration of solubility due to excessive increase in molecular weight can be suppressed.

Examples of the commercial products of the both-end hydroxylated polysilicone include “X-22-160AS, KF6001, KF6002, KF-6003” manufactured by Shin-Etsu Chemical Co., Ltd., and the like. Specific examples of the “polyol compound having an oxygen atom only in the hydroxyl group and having 18 to 72 carbon atoms” include a diol compound having a skeleton obtained by hydrogenating dimer acid. And “SOVERMOL (registered trademark) 908” manufactured by Cognis.

In addition, a diol having a molecular weight of 300 or less that does not have a repeating unit can be used as the (a3) polyol compound as long as the effects of the present invention are not impaired. Specific examples of such low molecular weight diols include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, and 1,4-butane. Diol, 1,5-pentanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, 1,8-octanediol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, 1,9-nonanediol, 2-methyl-1,8-octanediol, 1,10-decamethylene glycol, 1,2-tetradecanediol, 2,4-diethyl-1,5-pentanediol, butylethylpropanediol 1,3-cyclohexanedimethanol, 1,3-xylylene glycol, 1,4-xylylene Call, diethylene glycol, triethylene glycol, or dipropylene glycol.

The above-mentioned polyurethane having a carboxyl group can be synthesized only from the above components (a1), (a2) or (a1), (a2), (a3). And (a4) monohydroxy compound and / or (a5) monoisocyanate compound may be synthesized for the purpose of imparting properties or suppressing the influence of the isocyanate group or hydroxyl group residue at the end of the polyurethane. it can.

(A4) Monohydroxy compound (a4) As the monohydroxy compound, 2-hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, cyclohexanedimethanol mono (meth) acrylate, each of the above (meta ) Caprolactone or alkylene oxide adduct of acrylate, glycerin di (meth) acrylate, trimethylol di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol penta (meth) acrylate, ditrimethylolpropane tri (meth) acrylate , Compounds having radically polymerizable double bonds such as allyl alcohol and allyloxyethanol, and compounds having carboxylic acids such as glycolic acid and hydroxypivalic acid. It is.

(A4) Monohydroxy compounds can be used singly or in combination of two or more. Among these compounds, 2-hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, allyl alcohol, glycolic acid, and hydroxypivalic acid are preferable, and 2-hydroxyethyl (meth) ) Acrylate and 4-hydroxybutyl (meth) acrylate are more preferred.

In addition, (a4) monohydroxy compounds include methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, t-butanol, amyl alcohol, hexyl alcohol, octyl alcohol and the like.

(A5) Monoisocyanate compound (a5) Monoisocyanate compounds include (meth) acryloyloxyethyl isocyanate, 2-hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate to diisocyanate compounds, Cyclohexanedimethanol mono (meth) acrylate, caprolactone or alkylene oxide adduct of each (meth) acrylate, glycerin di (meth) acrylate, trimethylol di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol penta Radicals such as mono-adducts of (meth) acrylate, ditrimethylolpropane tri (meth) acrylate, allyl alcohol, and allyloxyethanol It includes compounds having a carbon double bond - carbon.

Also, examples of the monoisocyanate hydroxy compound used for the purpose of suppressing the influence of the terminal hydroxyl residue include phenyl isocyanate, hexyl isocyanate, and dodecyl isocyanate.

The above-mentioned polyurethane having a carboxyl group is obtained by using the above-mentioned (a1) polyisocyanate compound and (a2) carboxyl in the presence or absence of a known urethanization catalyst such as dibutyltin dilaurate using an appropriate organic solvent. It can be synthesized by reacting a dihydroxy compound having a group, (a3) a polyol compound, and (a4) a monohydroxy compound or (a5) a monoisocyanate compound as necessary. It is not necessary to consider the mixing of tin and the like.

The organic solvent is not particularly limited as long as it has low reactivity with the isocyanate compound, but when the polyurethane obtained after the reaction is used as a raw material for the conductive pattern forming composition (conductive ink) in a solution, A solvent having a boiling point of 110 ° C. or higher, preferably 150 ° C. or higher, more preferably 200 ° C. or higher is preferable. When the boiling point is 110 ° C. or higher, volatilization of the solvent during ink preparation can be suppressed. Examples of such solvents include toluene, xylene, ethylbenzene, nitrobenzene, isophorone, diethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol monomethyl ether monoacetate, propylene glycol monomethyl ether monoacetate, propylene glycol monoethyl ether monoacetate, diethylene Propylene glycol monomethyl ether monoacetate, diethylene glycol monoethyl ether monoacetate, methyl methoxypropionate, ethyl methoxypropionate, methyl ethoxypropionate, ethyl ethoxypropionate, n-butyl acetate, isoamyl acetate, ethyl lactate, cyclohexanone, N, N -Dimethylformamide, N, N-dimethylacetate Amide, N- methylpyrrolidone, .gamma.-butyrolactone, and dimethyl sulfoxide.

In view of the fact that the organic solvent with low solubility of the polyurethane to be produced is not preferable, and considering that polyurethane is used as the raw material of the ink in electronic material applications, among these, in particular, propylene glycol monomethyl ether monoacetate, propylene glycol monoacetate. Ethyl ether monoacetate, dipropylene glycol monomethyl ether monoacetate, diethylene glycol monoethyl ether monoacetate, diethylene glycol monobutyl ether monoacetate, γ-butyrolactone and the like are preferable.

Further, when the obtained polyurethane is used as a conductive ink raw material after solvent substitution, it is more preferable to use a solvent having a boiling point lower than 110 ° C. because the lower the boiling point, the easier the distillation under reduced pressure. Examples of such a solvent include cyclohexane, ethyl acetate, acetone, methyl ethyl ketone, chloroform, methylene chloride and the like. Even when a solvent having a boiling point of 110 ° C. or higher is used, there is no problem in carrying out the solvent replacement.

The order in which the raw materials are charged is not particularly limited. Usually, (a2) a dihydroxy compound having a carboxyl group and (a3) a polyol compound are charged first and dissolved in a solvent, and more preferably 20 to 150 ° C. Is added dropwise with (a1) polyisocyanate compound at 50 to 120 ° C., and then reacted at 30 to 160 ° C., more preferably at 50 to 130 ° C. When the temperature at the time of dropping is 20 ° C. or higher, (a2) the dihydroxy compound having a carboxyl group is easily dissolved, and when it is 150 ° C. or lower, runaway due to rapid progress of the reaction at the time of dropping can be prevented. Further, when the temperature during the reaction is 30 ° C. or higher, the polymerization reaction proceeds rapidly, and when it is 160 ° C. or lower, the coloring of the polyurethane can be suppressed. When (a3) a polyol compound is not used, only (a2) a dihydroxy compound having a carboxyl group is charged first.

The starting molar ratio of the raw material is adjusted according to the molecular weight and acid value of the target polyurethane resin, but when the (a4) monohydroxy compound is introduced into the polyurethane resin, the end of the polyurethane molecule becomes an isocyanate group. In addition, it is necessary to use (a1) a polyisocyanate compound in excess of (a2) a carboxyl group-containing dihydroxy compound and (a3) a polyol compound (so that isocyanate groups are in excess of the total of hydroxyl groups).

Specifically, these charged molar ratios are such that (a1) isocyanate group of polyisocyanate compound: ((a2) hydroxyl group of dihydroxy compound having carboxyl group + (a3) hydroxyl group of polyol compound) is 0.5 to 1. .5: 1, preferably 0.8 to 1.2: 1, more preferably 0.95 to 1.05. (A1) When the molar ratio of isocyanate groups of the polyisocyanate compound is 0.5 or more and 1.5 or less, it becomes easy to obtain a polyurethane having a large molecular weight.

The ratio of (a2) the hydroxyl group of the dihydroxy compound having a carboxyl group to ((a2) the hydroxyl group of the dihydroxy compound having a carboxyl group + (a3) the hydroxyl group of the polyol compound) is preferably 1: 0.05 to 1, preferably It is 1: 0.35 to 1, more preferably 1: 0.45 to 1. (A2) When the ratio of the hydroxyl group of the dihydroxy compound having a carboxyl group is 0.05 or more, an amount of a metal salt site necessary for improving the electrical conductivity can be introduced into the polyurethane.

When (a4) a monohydroxy compound is used, the number of moles of the (a1) polyisocyanate compound is made larger than the number of moles of ((a2) dihydroxy compound having a carboxyl group + (a3) polyol compound), and (a4) The monohydroxy compound is preferably used in an amount of 0.5 to 1.5 times mol, preferably 0.8 to 1.2 times mol, based on the excess number of moles of isocyanate groups. (A4) When the molar amount of the monohydroxy compound is 0.5 times the molar amount or more, the isocyanate group at the terminal of the polyurethane can be reduced, and when it is 1.5 times the molar amount or less, the unreacted monohydroxy compound Can be prevented from adversely affecting the subsequent processes.

In order to introduce the (a4) monohydroxy compound into the polyurethane having a carboxyl group, the reaction between the (a2) dihydroxy compound having a carboxyl group and the (a3) polyol compound and the (a1) polyisocyanate compound is almost completed. In order to react the isocyanate group remaining at both ends of the polyurethane having a carboxyl group with the (a4) monohydroxy compound, the (a4) monohydroxy compound is added to the reaction solution at 20 to 150 ° C., more preferably 70 ° C. Add dropwise at ~ 120 ° C and then hold at the same temperature to complete the reaction. When the dropping and the reaction temperature are 20 ° C. or higher, the reaction of the remaining isocyanate group and (a4) monohydroxy group proceeds rapidly, and when the temperature is 150 ° C. or lower, the reaction rapidly proceeds during the dropping. Can be prevented.

(A5) When a monoisocyanate compound is used, the number of moles of ((a2) dihydroxy compound having a carboxyl group + (a3) polyol compound) is made larger than the number of moles of (a1) polyisocyanate compound, and an excess of hydroxyl groups The molar amount is 0.5 to 1.5 times the molar amount, preferably 0.8 to 1.2 times the molar amount. (A5) When the molar amount of the monoisocyanate compound is 0.5 times or more, it is possible to prevent the hydroxyl group from remaining at the terminal of the polyurethane, and when it is 1.5 times or less, the monoisocyanate compound. Can be prevented from adversely affecting the subsequent processes.

In order to introduce the (a5) monoisocyanate compound into the polyurethane having a carboxyl group, the reaction between the (a2) dihydroxy compound having a carboxyl group and the (a3) polyol compound and the (a1) polyisocyanate compound is almost completed. In order to react the hydroxyl groups remaining at both ends of the polyurethane having a carboxyl group with the (a5) monoisocyanate compound, the (a5) monoisocyanate compound is reacted in the reaction solution at 20 to 150 ° C., more preferably 50 to The reaction is completed by dropping at 120 ° C. and then holding at the same temperature. When the dropping and reaction temperature are 20 ° C. or higher, the reaction between the remaining hydroxyl group and the (a5) monoisocyanate compound proceeds rapidly, and when it is 150 ° C. or lower, the reaction proceeds rapidly during the dropping and runs away. Can be prevented.

The number average molecular weight of the polyurethane having a carboxyl group is preferably 1,000 to 100,000, and more preferably 3,000 to 50,000. Here, the molecular weight is a value in terms of polystyrene measured by gel permeation chromatography (hereinafter referred to as GPC). When the number average molecular weight is 1,000 or more, adhesion between the finally formed conductive pattern and the substrate is expressed. When the number average molecular weight is 100,000 or less, the molecular weight becomes too high, so that the solvent dissolves in the solvent. It is possible to suppress the deterioration of properties and the viscosity becoming too high after dissolution.

In addition, in this specification, the measurement conditions of GPC are as having described in the Example mentioned later.

The acid value of the polyurethane having a carboxyl group is preferably 5 to 160 mgKOH / g, more preferably 10 to 150 mgKOH / g. When the acid value is 5 mgKOH / g or more, an amount of the metal salt portion necessary for improving the conductivity can be introduced into the polyurethane. Moreover, the solubility to a solvent is favorable in it being 160 mgKOH / g or less, and there are many kinds of the solvent which can be used.

In addition, in this specification, the acid value of resin is the value measured by the method described in the Example mentioned later.

The metal atom M forming a salt with all or part of the carboxyl groups of the polyurethane having a carboxyl group is a metal belonging to Group 11 of the periodic table. As the metal atom M, silver and copper are preferable because of low volume resistivity.

The polyurethane metal salt may be synthesized by any method. For example, after neutralizing the carboxyl group in the said polyurethane with a base, it is made to react with the metal salt of inorganic acids, such as nitric acid, a sulfuric acid, and carbonic acid. In addition, a basic oxide or hydroxide of a metal such as a carboxyl group and silver oxide, silver hydroxide, copper oxide, cuprous oxide, copper hydroxide or the like can be directly reacted. When the carboxyl group is reacted directly with a metal basic oxide or hydroxide, the powder of the basic oxide or hydroxide may be added directly to the polyurethane solution, or the powder is dispersed in advance in a solvent. To the polyurethane solution. In the case where the powder adheres to the bottom of the container during the reaction and the reaction stops, the latter method makes it difficult for the powder to become lumpy and prevents sticking. Furthermore, you may make it react by heating as needed. The reaction temperature is 20 ° C to 150 ° C, more preferably 20 ° C to 120 ° C. When the temperature is 20 ° C. or higher, the reaction proceeds rapidly, and even if the solid content concentration of the metal salt obtained as a solution is increased, the fluidity is increased, so that the reaction can be promoted. Therefore, the degree of freedom of the composition of the ink (conductive pattern forming composition) can be increased. Moreover, when it is 150 degrees C or less, the thermal decomposition of the polyurethane by overheating can be prevented. Examples of the method for synthesizing the metal salt of polyurethane include the following methods.

<Synthesis of silver salt>
(1) A method in which a carboxyl group in polyurethane is neutralized with sodium hydroxide to form a sodium salt, and then reacted with silver nitrate to bond the carboxyl group and silver.
(2) A method in which a carboxyl group in polyurethane and silver oxide are reacted to bond the carboxyl group and silver.

<Synthesis of copper salt>
(1) A method in which a carboxyl group in polyurethane is neutralized with sodium hydroxide to form a sodium salt, and then reacted with copper sulfate to bond the carboxyl group and copper.
(2) A method in which a carboxyl group in polyurethane is reacted with copper hydroxide to bond the carboxyl group and copper.

Of the carboxyl groups of the polyurethane, the ratio of being a metal salt is unclear because it is affected by the chemical structure, molecular weight, and acid value of the original polyurethane, but is preferably 5 to 100 mol%. 35 to 100 mol% is preferred. The effect which improves electrical conductivity can be expressed as the ratio made into metal salt is 5 mol% or more.

The conductive pattern forming composition according to the embodiment includes the binder resin for conductive composition (A), the conductive material (B), and a solvent (C) for dissolving the binder resin for conductive composition. It is configured.

The conductive material (B) that can be used is not particularly limited as long as it has conductivity. It is preferable to use mainly at least one of metal particles (including metal nanoparticles), metal nanowires, and metal nanotubes. A metal nanowire and / or a metal nanotube is a thin wire metal with a diameter of nanometer order size. A metal nanowire is a wire shape, and a metal nanotube is a conductive material having a porous or non-porous tube shape. Material. In this specification, “wire” and “tube” are both linear, but the former is not hollow (hollow) along the long axis, and the latter is long along the long axis. Intended to be hollow (hollow). The property may be flexible or rigid. Either a metal nanowire or a metal nanotube may be used, or a mixture of both may be used. The metal constituting the conductive material may be the same type of metal as the metal forming the metal salt in the binder resin for conductive compositions, or may be a different metal. The metal species is appropriately selected according to the conductivity, corrosion resistance and other physical properties required for the conductive pattern forming composition (conductive ink). For example, silver, copper, nickel, gold, platinum, palladium, aluminum, etc. can be mentioned. In particular, it is preferable to use silver or copper because of its high conductivity.

The shape of the metal particles is not particularly limited, but the use of flat particles is preferable in that the area where the particles are in contact with each other is increased and resistance is easily reduced. The larger the aspect ratio of flat metal particles (width / thickness of the flat metal particles), the larger the contact area between the metal particles, which is advantageous in terms of conductivity. Drop (fine pattern printing is difficult), dispersibility is also reduced. Therefore, the preferred aspect ratio is in the range of 3 to 200, more preferably in the range of 5 to 100. The shape of the flat metal particles was changed by observing 10 points by SEM at a magnification of 10,000 times to measure the thickness and width of the flat metal particles, and the thickness was obtained as the number average value thereof. The thickness is preferably 5 nm to 2 μm, more preferably 20 nm to 1 μm.

In addition, as an average particle diameter (approximate particle diameter in the case of spherical particles) of other shapes of metal particles including flat metal particles, for example, those in the range of 0.01 to 100 μm can be used. The thickness is preferably in the range of 0.02 to 50 μm, more preferably in the range of 0.04 to 10 μm. Here, the average particle diameter is a median diameter (D ₅₀ ) measured by a laser diffraction method. For the measurement, for example, SALD-3100 (manufactured by Shimadzu Corporation) or LA-950V2 (manufactured by Horiba Seisakusho) is used. Can do.

The average diameter of metal nanowires and metal nanotubes is preferably thinner from the viewpoint of conductivity, but thicker from the viewpoint of strength and ease of handling. Therefore, the average value of the wire diameter is preferably 500 nm or less, more preferably 200 nm or less, still more preferably 100 nm or less, and particularly preferably 80 nm or less from the viewpoint of conductivity. On the other hand, from the viewpoints of strength and ease of handling, the thickness is preferably 1 nm or more, more preferably 5 nm or more, and further preferably 10 nm or more.

In addition, the average length of the major axis of the metal nanowires and metal nanotubes is preferably longer from the viewpoint of conductivity, but it is necessary to limit the length to some extent in order to cope with the fine pattern. Therefore, the average value of the wire length is preferably 1 μm or more from the viewpoint of conductivity, more preferably 2 μm or more, and further preferably 5 μm or more. On the other hand, it is preferably 100 μm or less, more preferably 50 μm or less, and even more preferably 30 μm or less from the viewpoint of handling fine patterns.

In the metal nanowire and the metal nanotube, the average diameter thickness and the average long axis length satisfy the above ranges, and the average aspect ratio is preferably larger than 5, more preferably 10 or more, More preferably, it is more preferably 200 or more. Here, the aspect ratio is a value obtained by a / b when the average diameter of the metal nanowires and metal nanotubes is approximated as b and the average length of the major axis is approximated as a. a and b can be arbitrarily measured using a scanning electron microscope and obtained as an average value.

In addition to the metal particles, metal nanowires, and metal nanotubes, metal oxides and carbon-based materials can be used. The metal constituting the metal oxide particles may be the same type of metal as the metal forming the metal salt in the binder resin for conductive compositions, or may be a different metal. The metal species is appropriately selected according to the electrical conductivity, corrosion resistance and other physical properties required for the conductive pattern forming composition. Examples of the metal oxide include indium tin oxide (ITO), zinc oxide, tin dioxide, indium oxide and the like. Examples of the carbon-based material include carbon black, graphite, and carbon nanotube.

The shape of the metal oxide particles is not particularly limited, but it is preferable to use flat particles like the metal particles. Moreover, about a preferable average particle diameter, it is equivalent to a metal particle.

As said solvent (C), if the polyurethane which has a carboxyl group used for binder resin for conductive compositions can be melt | dissolved and an appropriate viscosity can be provided when using the composition for conductive pattern formation as an ink, Can be used. Specific examples include ethyl carbitol acetate, ethyl carbitol, butyl carbitol acetate, butyl carbitol, terpineol, dihydroterpineol, and isobornylcyclohexanol.

The ratio of the binder resin for conductive composition (A) in the composition for forming a conductive pattern, the ratio of the conductive material (B), and the ratio of the solvent (C) are obtained when the metal particles (B1) are used. This is different from the case of using metal nanowires and / or metal nanotubes (B2). In the case where the metal particles (B1) are electrically conductive, the metal particles (B1) are in contact with each other at points or planes, whereas when metal nanowires and / or metal nanotubes (B2) are used, the intersection (overlapping) portion. Since the contact (connection) is made only with the metal nanowire and / or the metal nanotube (B2), the ratio of the metal composition (B1) to the entire composition is smaller than when the metal particle (B1) is used. Moreover, the ratio of the binder resin (A) and the ratio of the solvent (C) are relatively larger when the metal nanowires and / or metal nanotubes (B2) are used than when the metal particles (B1) are used.

When the metal particles (B1) are used as the conductive material (B), the ratio of the binder resin (A) for the conductive composition is 1 to 15 parts by weight with respect to 100 parts by weight of the metal particles (B1) in the composition. Parts by mass, preferably 2 to 10 parts by mass, more preferably 2.5 to 5 parts by mass. When the ratio is 1 part by mass or more, the dispersibility of the conductive material is maintained, and the adhesion between the conductive pattern and the substrate is expressed. Moreover, when the ratio is 15 parts by mass or less, the deterioration of the conductivity due to the excessive increase of the polymer component contained in the finally formed conductive pattern can be suppressed.

Further, the ratio of the metal particles (B1) to the whole composition is 20% by mass to 95% by mass, preferably 30% by mass to 92% by mass, and more preferably 45% by mass to 90% by mass. When the ratio of the metal particles is 20% by mass or more, the conductivity of the finally formed conductive pattern is obtained. Moreover, when the ratio of the metal particles is 95% by mass or less, the viscosity of the conductive pattern forming composition becomes too high, and problems such as blurring do not occur when forming a conductive pattern by printing or coating.

When the metal particles (B1) are used as the conductive material (B), the proportion of the solvent (C) is 5% by mass to 80% by mass, preferably 10% by mass to 70% by mass, and more preferably with respect to the entire composition. Is 15% by mass to 60% by mass. If it is 5 mass% or more, the said binder resin for conductive compositions (A) can fully be dissolved. Moreover, it can be set as the viscosity of the composition for conductive pattern formation which can carry out pattern printing as it is 80 mass% or less.

When the metal nanowire and / or the metal nanotube (B2) is used as the conductive material (B), the ratio of the binder resin (A) for the conductive composition is the same as the metal nanowire and / or the metal nanotube (B2) 100 in the composition. The amount is 10 parts by mass to 400 parts by mass, preferably 50 parts by mass to 300 parts by mass, and more preferably 100 parts by mass to 250 parts by mass with respect to parts by mass. If the ratio is 10 parts by mass or more, it can be expected that the resistance reduction effect derived from the metal salt site is exhibited. Moreover, when the ratio is 400 parts by mass or less, it is possible to suppress the deterioration of the conductivity due to the excessive increase of the polymer component contained in the finally formed conductive pattern.

The ratio of metal nanowires and / or metal nanotubes (B2) to the whole composition is 0.01 to 10% by mass, preferably 0.02 to 5% by mass, more preferably 0.05 to 2% by mass. . When the metal nanowires and / or metal nanotubes are 0.01% by mass or more, it is not necessary to print the transparent conductive layer thick in order to ensure desired conductivity, and printing becomes easy. Moreover, if it is 10 mass% or less, in order to ensure a desired optical characteristic, it becomes unnecessary to thinly print a transparent conductive film layer, and also in this case, printing becomes easy.

When the metal nanowire and / or the metal nanotube (B2) is used as the conductive material (B), the ratio of the solvent (C) is 90% by mass or more, more preferably 98% by mass or more with respect to the entire composition. When the ratio is 90% by mass or more, it is possible to suppress deterioration of conductivity due to excessive increase of polymer components in the finally formed conductive pattern and deterioration of optical characteristics due to excessive increase of conductive components. .

As the binder resin, a carboxylate metal salt moiety represented by (COO) _n M in the polymer skeleton (M is a metal atom selected from metals belonging to Group 11 of the periodic table, and n is a valence of the metal atom M). The resin other than the polyurethane having the number) can be used in combination as long as the effects of the present invention are not impaired. When using together, it is preferable that the ratio of the said polyurethane with respect to all the binder resins is 50 mass% or more, It is more preferable that it is 70 mass% or more, It is further more preferable that it is 90 mass% or more. When the proportion of the polyurethane with respect to the total binder resin is 50% by mass or more, in the finally formed conductive pattern, there are too many polymer components that do not have the effect of reducing resistance, and the conductivity is not improved. Can be prevented. Examples of binder resins that can be used in combination include poly-N-vinyl pyrrolidone, poly-N-vinylacetamide, poly-N-vinyl compounds such as poly-N-vinylcaprolactam, polyethylene glycol, polypropylene glycol, and polyTHF. Such polyalkylene glycols, cellulose and derivatives thereof, epoxy resins, polyesters, chlorinated polyolefins, thermoplastic resins such as polyacrylic resins, thermosetting resins and the like.

In the conductive pattern forming composition according to the embodiment, other additives can be used in combination as necessary within a range not impairing the properties of the conductive pattern forming composition. Additives that can be used in combination may contain additives such as surfactants, antioxidants, fillers, thixotropic agents, leveling agents, and UV absorbers. In order to adjust the viscosity of the composition, a filler such as fumed silica can be used. These blending amounts (ratio to the whole composition) are preferably within 5% by mass.

The conductive pattern forming composition according to the embodiment includes a conductive resin (A), a conductive material (B), and a solvent (C) that dissolves the conductive composition binder resin. ), Additives that can be added as necessary are 100% by mass in total (ratio by mass), that is, binder resin for conductive composition (A) and conductive material (B ) And the solvent (C) for dissolving the binder resin for conductive composition, the total amount of the composition can be 100% by mass or less. There is no restriction | limiting in particular in the method to mix | blend, It can manufacture by mixing with a rotation revolution revolution stirrer, a homogenizer, a three roll, a high shear mixer, a propeller stirrer, a mix rotor, etc.

When the conductive pattern forming composition (conductive ink) according to the embodiment is used, the conductivity of the conductive pattern can be improved with low sintering energy. In this specification, the conductive pattern is formed as a result of sintering the conductive material by printing the conductive pattern forming composition on a base material in a predetermined pattern and applying energy as necessary. Pattern. This pattern is not necessarily a fine line, and a so-called solid shape such as a square having a certain area is also included in the pattern.

The substrate for applying and printing the conductive pattern forming composition of the present embodiment is not particularly limited as long as it is insulating. From the viewpoint of ease of application and printing, a plate shape, a sheet shape, and a film shape are preferable. For example, ceramics such as glass and alumina, polyester resins, cellulose resins, vinyl alcohol resins, vinyl chloride resins, cycloolefin resins, polycarbonate resins, acrylic resins, ABS resins, polyimide resins, and other thermoplastic resins, photocurable resins, A thermosetting resin etc. are mentioned. Furthermore, it is also possible to use these substrate surfaces by activating them using a treatment for improving the adhesion. Among the above base materials, glass having a functional group (hydroxyl group, carbonyl group, amino group, etc.) having an interaction (hydrogen bond, etc.) with urethane bond in the binder resin, polyester resin, cellulose resin, vinyl alcohol resin, acrylic resin, A polyimide resin or the like is preferable.

The conductive pattern printing method is not particularly limited as long as it is a known method. Spray coating, bar coating, roll coating, die coating, inkjet coating, screen coating, dip coating, letterpress printing method, intaglio printing method, gravure printing method Etc. can be used. Depending on the method of application and the conditions of the material, the substrate may be heated after wet coating to remove the applied material and the solvent used, or the process of washing away the solvent by washing, etc. .

Hereinafter, embodiments of the present invention will be specifically described. In addition, the following examples are for facilitating understanding of the present invention, and the present invention is not limited to these examples.

<Measurement method of physical properties>
(GPC)
The value of the weight average molecular weight is a value in terms of polystyrene measured by GPC, and the measurement conditions are as follows.
・ Measuring device Shodex GPC-101
・ Column Shodex column LF-804
・ Mobile phase Tetrahydrofuran (THF)
・ Flow rate 1.0mL / min
・ Measurement time 40min
・ Detector Shodex RI-71S
・ Temperature 40.0 ℃
Sample volume Sample loop 100 μL
・ Sample concentration Prepared to be about 1% by mass THF solution

(Acid value)
The acid value of the resin was measured by the following method.
About 1 g of a sample is precisely weighed with a precision balance in a 100 ml flask, and 30 ml of methanol is added to dissolve it. Furthermore, add 1 to 3 drops of phenolphthalein ethanol solution as an indicator and stir well until the sample is uniform. This is titrated with a 0.1N potassium hydroxide-ethanol solution, and the end point of neutralization is obtained when the indicator is slightly red for 30 seconds. The value obtained from the result using the following calculation formula is defined as the acid value of the resin.
Acid value (mgKOH / g) = [B × f × 5.611] / S
B: Amount of 0.1N potassium hydroxide-ethanol solution used (ml)
f: Factor of 0.1N potassium hydroxide-ethanol solution S: Amount of sample collected (g)

(TG-DTA)
Differential heat-thermogravimetry was performed under the following measurement conditions.
・ Measurement device Differential thermothermal weight simultaneous measurement device TG / DTA6200 (SII Nanotechnology Inc.)
・ Temperature range 30 ℃ -500 ℃
・ Temperature increase rate 10 ℃ / min ・ Atmosphere Nitrogen gas

<Metal salt of polypropylene glycol 1000-containing polyurethane (acid value 40 mgKOH / g)>
Synthesis Example 1 (Synthesis of polyurethane PU-1 having carboxyl group)
62.11 g of polypropylene glycol 1000 (weight average molecular weight 1000, manufactured by NOF Corporation) as a diol compound was added to a 500 mL four-necked separable flask equipped with a dropping funnel, a stirring device, a thermocouple for temperature measurement, and a Liebig condenser. 62 mmol, 0.45 equivalent to diisocyanate), 11.42 g (77 mmol, 0 to diisocyanate) dimethylolbutanoic acid (hereinafter abbreviated as DMBA) as a dihydroxy compound having a carboxyl group. .55 equivalents) and 104.41 g of ethyl carbitol acetate (manufactured by Daicel Corporation) as a solvent were charged, and all raw materials were dissolved at 45 ° C. Using a dropping funnel, 30.89 g (139 mmol) of isophorone diisocyanate (hereinafter abbreviated as IPDI) (manufactured by Sumika Bayer Urethane Co., Ltd., Desmodur (registered trademark) I) was added dropwise as a diisocyanate compound over 5 minutes. After completion of dropping, the temperature was raised to 110 ° C. over 1 hour, and then the reaction was continued at 110 ° C. for 5 hours. After confirming that the absorption spectrum of the isocyanate group observed at 2270 cm ⁻¹ in the infrared absorption spectrum almost disappeared, 0.17 g of isobutanol (manufactured by Wako Pure Chemical Industries, Ltd.) was added as an end-capping agent. After reacting at 110 ° C. for 1 hour, it was allowed to cool to room temperature to obtain a polyurethane solution having a uniform carboxyl group. The solid content concentration determined by drying under reduced pressure using a vacuum dryer (120 ° C., 3 hours) was 50% by mass.

The obtained polyurethane has a structural unit represented by the following formula (7).

In the formula, x1 + y1 = 1, x1 = 0.55, and y1 = 0.45. n ₆ represents a positive integer, is approximately 17 from the value of the weight-average molecular weight.

The measured value of the acid value of the solid content of the obtained polyurethane solution having a carboxyl group was 43 mgKOH / g, and the weight average molecular weight was 1.2 × 10 ⁴ .

Example 1
(Synthesis of polyurethane silver salt PU-1Ag ₁ using silver nitrate)
2.03 g (containing 0.73 mmol of carboxyl group) of the polyurethane solution having a carboxyl group obtained in Synthesis Example 1 above was dissolved in 20 ml of acetone (manufactured by Wako Pure Chemical Industries, Ltd.), and sodium hydroxide ( A solution prepared by dissolving 0.03 g (0.73 mmol) of Wako Pure Chemical Industries, Ltd. in 3 ml of water was added and stirred until uniform. To this, 0.13 g (0.73 mmol) of silver nitrate (manufactured by Wako Pure Chemical Industries, Ltd.) dissolved in 5 ml of water was added dropwise to cause precipitation. The supernatant liquid is removed by decantation, air-dried overnight, and dried to dryness. To completely remove the remaining solvent, it is dried under reduced pressure for 1 hour using a vacuum dryer while heating at 100 ° C. A salt was obtained (yield 0.56 g).

Fig. 1 shows the results of simultaneous differential thermal-thermogravimetric measurement (TG-DTA) of polyurethane silver salt. The mass ratio of the residue after completion of the TG-DTA measurement was 9.9 mass%, which was a value close to 7.4 mass%, which is the theoretical value of the silver content calculated from the molecular formula.

Example 2
(Synthesis of polyurethane silver salt PU-1Ag ₂ using silver oxide)
6.04 g of the polyurethane solution having a carboxyl group obtained in Synthesis Example 1 (containing a carboxyl group corresponding to 2.2 mmol) was dissolved in 14.05 g of diethylene glycol monoethyl ether (manufactured by Junsei Chemical Co., Ltd.). .26 g of silver oxide (manufactured by Wako Pure Chemical Industries, Ltd.) (1.1 mmol, 2.2 mmol in terms of silver) was added. The mixture was stirred at room temperature for 10 hours under light shielding, and it was confirmed that silver oxide had disappeared and became a uniform solution.

A portion of the obtained silver salt solution (solid content concentration: 16% by mass) was dried under reduced pressure for 1 hour using a vacuum dryer while heating at 100 ° C. TG-DTA measurement of the solid polyurethane silver salt obtained after drying was performed. The measurement results are shown in FIG. The mass ratio of the residue after completion of the TG-DTA measurement was 8.1 mass%, which was a value close to 7.4 mass%, which is the theoretical value of the silver content calculated from the molecular formula. 1 and 2, it was confirmed that the same polyurethane silver salt obtained by the method using silver nitrate and the polyurethane silver salt obtained by the method using silver oxide were obtained.

In order to confirm that a silver atom is coordinated to the carboxyl group portion of the resin, IR measurement of the obtained solid was performed. The IR spectrum of the polyurethane obtained in Synthesis Example 1 is shown in FIG. 3, and the IR spectrum of the polyurethane silver salt obtained in Example 1 is shown in FIG. Generally, if the carboxylic acid takes C = O at the double bond and the C-O single bond coordination structure such that the equivalent in the carboxyl group forms a salt, in the vicinity of 1600 cm ^-1 and around 1400 cm ^-1 It is known that a peak is observed. Since such a change was not seen in the comparison between FIG. 3 and FIG. 4, it was suggested that in this silver salt, the silver atom is coordinated to only one oxygen atom.

In order to confirm that the silver atom is coordinated to the carboxyl group portion of the resin, NMR measurement was performed in addition to the IR measurement. The ¹ H-NMR spectrum of the resin obtained in Synthesis Example 1 is shown in FIG. 5, and the ¹ H-NMR spectrum of the polyurethane silver salt obtained in Example 1 is shown in FIG. In order to prevent moisture from entering, the sample was dried under reduced pressure for 1 hour in a vacuum dryer immediately before the measurement, and deuterated dimethyl sulfoxide was used as the heavy solvent. As a result, the peak of the carboxyl group observed in the vicinity of 12 ppm in FIG. 5 disappeared in FIG. 6, so that it was confirmed that the silver atom was coordinated to the carboxyl group portion.

The obtained silver salt of polyurethane has a structural unit represented by the following formula (8).

Example 3
(Synthesis of polyurethane copper salt PU-1Cu using copper sulfate)
2.02 g (containing 0.73 mmol of carboxyl group) of the polyurethane solution having a carboxyl group obtained in Synthesis Example 1 above was dissolved in 20 ml of acetone (manufactured by Wako Pure Chemical Industries, Ltd.), and sodium hydroxide ( A solution prepared by dissolving 0.03 g (0.73 mmol) of Wako Pure Chemical Industries, Ltd. in 3 ml of water was added and stirred until uniform. A solution prepared by dissolving 0.092 g (0.37 mmol, 0.5 equivalent to the carboxyl group) of copper sulfate pentahydrate (manufactured by Wako Pure Chemical Industries, Ltd.) in 5 ml of water was added dropwise to this and precipitated. Gave rise to After stirring at room temperature for 2 hours, the supernatant liquid is removed by decantation, and in order to completely remove the remaining solvent, it is dried under reduced pressure for 1 hour using a vacuum dryer while heating at 100 ° C. A salt was obtained (yield 0.62 g).

The TG-DTA measurement result of the obtained copper salt is shown in FIG. The mass ratio of the residue after completion of the TG-DTA measurement was 2.3 mass%, which coincided with 2.3 mass%, which is the theoretical value of the copper content calculated from the molecular formula.

In order to confirm that a copper atom is coordinated to the carboxyl group portion of the resin, IR measurement of the obtained solid was performed. The IR spectrum of the polyurethane copper salt obtained in Example 3 is shown in FIG. 3 with Fig. 8, since the new peak in 1618cm ^-1 and 1410 cm ^-1 in FIG. 8 is observed, the copper atoms to form a carboxyl group and salts, C = O double bond and C- It was confirmed that the O single bond had an equivalent coordination structure.

The obtained copper salt of polyurethane has a structural unit represented by the following formula (9). In the following formula, only the coordination structure around the copper atom is shown for simplification.

The dotted line in the formula represents a coordination bond. Urethane bond units that are cross-linked by copper atoms may be contained in the same polyurethane skeleton, or may be contained in different polyurethane skeletons. Actually, since the divalent copper atom is a substitutionally active metal species, it is considered that the polyurethane chain cross-linked with the copper atom is exchanged over time. In addition, there is a possibility that a lanthanum type binuclear complex in which four carboxyl groups are coordinated to two copper atoms may be partially formed. In either case, the ratio of the carboxyl group and the copper atom is 2: 1. There is no change in the formation of salt.

<Silver salt of polyethylene glycol 400-containing polyurethane>
Synthesis Example 2 (Synthesis of polyurethane PU-2 having carboxyl group)
24.95 g of polyethylene glycol 400 (weight average molecular weight 400, manufactured by NOF Corporation) as a diol compound in a 500 mL four-necked separable flask equipped with a dropping funnel, a stirring device, a thermocouple for temperature measurement, and a Liebig condenser. 62 mmol, 0.45 equivalent to diisocyanate), 11.41 g (77 mmol, 0.55 equivalent to diisocyanate) DMBA (manufactured by Nippon Kasei Co., Ltd.) as a dihydroxy compound having a carboxyl group, and ethyl carbitol as a solvent 100.90 g of acetate (manufactured by Daicel Corporation) was charged, and all raw materials were dissolved at 55 ° C. Using a dropping funnel, 30.90 g (139 mmol) of IPDI (manufactured by Sumika Bayer Urethane Co., Ltd., Desmodur (registered trademark) I) was added dropwise as diisocyanate over 5 minutes. After completion of the dropwise addition, the temperature was raised to 110 ° C. over 1 hour, and then the reaction was continued at 110 ° C. for 5 hours. After confirming that the absorption spectrum of the isocyanate group observed at 2270 cm ⁻¹ in the infrared absorption spectrum almost disappeared, 0.17 g of isobutanol (manufactured by Wako Pure Chemical Industries, Ltd.) was added as an end-capping agent. After reacting at 110 ° C. for 1 hour, it was allowed to cool to room temperature to obtain a polyurethane solution having a uniform carboxyl group. The solid content concentration determined by drying under reduced pressure using a vacuum dryer (120 ° C., 2 hours) was 40% by mass.

The obtained polyurethane has a structural unit represented by the following formula (10).

In the equation, x2 + y2 = 1, x2 = 0.55, and y2 = 0.45. n ₇ is a positive integer and is approximately 9 from the value of the weight average molecular weight.

The actually measured value of the acid value of the solid content of the obtained polyurethane solution having a carboxyl group was 65 mgKOH / g, and the weight average molecular weight was 1.0 × 10 ⁴ .

Example 4
(Synthesis of polyurethane silver salt PU-2Ag ₁ using silver nitrate)
2.53 g of the polyurethane solution having a carboxyl group obtained in Synthesis Example 2 (containing 1.1 mmol of carboxyl group) was dissolved in 20 ml of acetone (manufactured by Wako Pure Chemical Industries, Ltd.), and sodium hydroxide ( A solution prepared by dissolving 0.046 g (1.1 mmol) of Wako Pure Chemical Industries, Ltd. in 5 ml of water was added and stirred until uniform. A solution prepared by dissolving 0.20 g (1.1 mmol) of silver nitrate (manufactured by Wako Pure Chemical Industries, Ltd.) in 5 ml of water was added dropwise thereto to cause precipitation. After stirring at room temperature for 30 minutes, the supernatant liquid is removed by decantation, air-dried overnight, dried, and then heated at 100 ° C. using a vacuum dryer to completely remove the remaining solvent. It was dried under reduced pressure for 1 hour to obtain a silver salt of polyurethane (yield 0.47 g).

TG-DTA measurement results of polyurethane silver salt are shown in FIG. The mass ratio of the residue after the TG-DTA measurement was 15.2% by mass, which was close to 11.0% by mass, which is the theoretical value of the silver content calculated from the molecular formula.

Example 5
(Synthesis of polyurethane silver salt PU-2Ag ₂ using silver oxide)
5.02 g (containing 2.2 mmol of carboxyl group) of the polyurethane solution having a carboxyl group obtained in Synthesis Example 2 was dissolved in 15.02 g of diethylene glycol monoethyl ether (manufactured by Junsei Chemical Co., Ltd.). .26 g of silver oxide (manufactured by Wako Pure Chemical Industries, Ltd.) (1.1 mmol, 2.2 mmol in terms of silver) was added. The mixture was stirred at room temperature for 15 hours under light shielding, and it was confirmed that the silver oxide disappeared and became a uniform solution.

A part of the obtained polyurethane silver salt solution (solid content concentration 11% by mass) was dried under reduced pressure for 1 hour using a vacuum dryer while heating at 100 ° C. TG-DTA measurement of the solid silver salt obtained after drying was performed. The measurement results are shown in FIG. The mass ratio of the residue after completion of the TG-DTA measurement was 10.9 mass%, which was close to 11.0 mass%, which is the theoretical value of the silver content calculated from the molecular formula. 9 and 10, it was confirmed that the same polyurethane silver salt obtained by the method using silver nitrate and the polyurethane silver salt obtained by the method using silver oxide were obtained.

The obtained silver salt of polyurethane has a structural unit represented by the following formula (11).

<Silver salt of polyurethane having carboxyl group composed of DMBA and IPDI>
Synthesis Example 3 (Synthesis of polyurethane PU-3)
In a 500 mL four-necked separable flask equipped with a dropping funnel, a stirrer, a thermocouple for temperature measurement, and a Liebig condenser, 20.59 g (139 mmol, diisocyanate) of DMBA (manufactured by Huzhou Nagamori Chemical) as a dihydroxy compound having a carboxyl group. 1.0 equivalent) and 120.27 g of ethyl carbitol acetate (manufactured by Daicel Corporation) as a solvent, and after confirming that DMBA is dissolved at 65 ° C., using a dropping funnel as a diisocyanate compound 30.97 g (139 mmol) of IPDI (manufactured by Sumika Bayer Urethane Co., Ltd., Desmodur (registered trademark) I) was added dropwise over 5 minutes. After completion of the dropping, the reaction solution was heated to 110 ° C. over 1 hour, and then the reaction was continued at 110 ° C. for 5 hours. After confirming that the absorption spectrum of the isocyanate group observed at 2270 cm ⁻¹ in the infrared absorption spectrum almost disappeared, 0.17 g of isobutanol (manufactured by Wako Pure Chemical Industries, Ltd.) was added as an end-capping agent. After reacting at 110 ° C. for 1 hour, the mixture was allowed to cool to room temperature, whereby 91.21 g of a polyurethane composition having a viscous paste-like carboxyl group precipitated and precipitated. The solid content concentration determined by drying under reduced pressure using a vacuum dryer (120 ° C., 2 hours) was 54 mass%.

The structural unit of the obtained polyurethane is represented by the following formula (12).

In the formula, n ₈ is a positive integer, is approximately 18 from the value of the weight-average molecular weight.

The obtained paste-like polyurethane group having a carboxyl group had an acid value of 150 mgKOH / g and a weight average molecular weight of 6.5 × 10 ³ .

Example 6
(Synthesis of polyurethane silver salt PU-3Ag ₁ )
1.74 g of the polyurethane composition having a paste-like carboxyl group obtained in Synthesis Example 3 (containing a carboxyl group corresponding to 2.6 mmol) was dissolved in 30 ml of methanol (manufactured by Wako Pure Chemical Industries, Ltd.) A solution prepared by dissolving 0.10 g (2.6 mmol) of sodium hydroxide (manufactured by Wako Pure Chemical Industries, Ltd.) in 1 ml of water was added and stirred until uniform. To this, 0.44 g (2.6 mmol) of silver nitrate (manufactured by Wako Pure Chemical Industries, Ltd.) dissolved in 5 ml of water was added dropwise to cause precipitation, followed by stirring at room temperature for 30 minutes. In order to completely remove the remaining solvent by suction filtration, the precipitate was dried under reduced pressure for 1 hour using a vacuum dryer while heating at 110 ° C. to obtain a silver salt of polyurethane (yield 0.72 g). .

The structural unit of the silver salt of the polyurethane is represented by the following formula (13).

The TG-DTA measurement result of the obtained polyurethane silver salt is shown in FIG. The mass ratio of the residue after completion of the TG-DTA measurement was 20.5 mass%, which was close to the theoretical value of 22.6 mass% of the silver content calculated from the molecular formula.

<Silver salt of polyurethane containing 2-butyl-2-ethyl-1,3-propanediol>
Synthesis Example 4 (Synthesis of polyurethane PU-4)
2-Butyl-2-ethyl-1,3-propanediol (Tokyo Chemical Industry Co., Ltd.) as a diol compound in a 500 mL four-necked separable flask equipped with a dropping funnel, a stirrer, a thermocouple for temperature measurement, and a Liebig condenser. Product) 8.81 g (55 mmol, 0.4 equivalents relative to diisocyanate), and 12.45 g (84 mmol, 0.6 equivalents relative to diisocyanate) DMBA (manufactured by Huzhou Nagamori Chemical) as the dihydroxy compound having a carboxyl group Then, 121.70 g of ethyl carbitol acetate (manufactured by Daicel Corporation) was charged as a solvent, and all raw materials were dissolved at 50 ° C. Using a dropping funnel, 30.90 g (139 mmol) of IPDI (manufactured by Sumika Bayer Urethane Co., Ltd., Desmodur (registered trademark) I) was added dropwise as a diisocyanate compound over 5 minutes. After completion of the dropwise addition, the temperature was raised to 110 ° C. over 1 hour, and then the reaction was continued at 110 ° C. for 5 hours. After confirming that the absorption spectrum of the isocyanate group observed at 2270 cm ⁻¹ in the infrared absorption spectrum almost disappeared, 0.17 g of isobutanol (manufactured by Wako Pure Chemical Industries, Ltd.) was added as an end-capping agent. After reacting at 110 ° C. for 1 hour, it was allowed to cool to room temperature to obtain a polyurethane solution having a uniform carboxyl group. The solid content concentration determined by drying under reduced pressure using a vacuum dryer (120 ° C., 2 hours) was 30% by mass.

The obtained polyurethane has a structural unit represented by the following formula (14).

In the formula, x3 + y3 = 1, x3 = 0.60, and y3 = 0.40. In the formula, Et represents an ethyl group, and Bu represents an n-butyl group.

The obtained polyurethane solution having a carboxyl group had an acid value of 93 mgKOH / g and a weight average molecular weight of 9.0 × 10 ³ .

Example 7
(Synthesis of polyurethane silver salt PU-4Ag ₁ )
1.56 g of a polyurethane solution having a carboxyl group obtained in Synthesis Example 4 (containing a carboxyl group corresponding to 0.78 mmol) was dissolved in 10 ml of ethanol (manufactured by Wako Pure Chemical Industries, Ltd.), and sodium hydroxide ( A solution prepared by dissolving 0.03 g (0.78 mmol) of Wako Pure Chemical Industries, Ltd. in 3 ml of water was added and stirred until uniform. A solution prepared by dissolving 0.12 g (0.78 mmol) of silver nitrate (manufactured by Wako Pure Chemical Industries, Ltd.) in 5 ml of water was added dropwise thereto to cause precipitation, followed by stirring at room temperature for 30 minutes. The precipitate was filtered with suction, and in order to completely remove the remaining solvent, it was dried under reduced pressure for 1 hour using a vacuum dryer while heating at 110 ° C. to obtain a silver salt of polyurethane (yield 0.41 g). .

The TG-DTA measurement result of the obtained silver salt is shown in FIG. The mass ratio of the residue after completion of the TG-DTA measurement was 14.8% by mass, which coincided with 14.8% of the theoretical value of the silver content calculated from the molecular formula.

The obtained silver salt of polyurethane has a structural unit represented by the following formula (15).

<Silver salt of polypropylene glycol 1000-containing polyurethane (acid value 90 mgKOH / g)>
Synthesis Example 5 (Synthesis of polyurethane PU-5)
In a 500 mL four-necked separable flask equipped with a dropping funnel, a stirrer, a thermocouple for temperature measurement, and a Liebig condenser, 24.06 g of polypropylene glycol 1000 (weight average molecular weight 1000, manufactured by NOF Corporation) as a diol compound ( 24 mmol, 0.17 equivalent to diisocyanate), 17.04 g (115 mmol, 0.83 equivalent to diisocyanate) DMBA (manufactured by Nippon Kasei Co., Ltd.) as a dihydroxy compound having a carboxyl group, and ethyl carbitol as a solvent 108.04 g of acetate (manufactured by Daicel Corporation) was charged, and all raw materials were dissolved at 60 ° C. Using a dropping funnel, 30.88 g (139 mmol) of IPDI (manufactured by Sumika Bayer Urethane Co., Ltd., Desmodur (registered trademark) I) was added dropwise as a diisocyanate compound over 5 minutes. After completion of dropping, the temperature was raised to 110 ° C. over 1 hour, and then the reaction was continued at 110 ° C. for 5 hours. After confirming that the absorption spectrum of the isocyanate group observed at 2270 cm ⁻¹ in the infrared absorption spectrum almost disappeared, 0.17 g of isobutanol (manufactured by Wako Pure Chemical Industries, Ltd.) was added as an end-capping agent. After reacting at 110 ° C. for 1 hour, it was allowed to cool to room temperature to obtain a polyurethane solution having a uniform carboxyl group. The solid content concentration determined by drying under reduced pressure using a vacuum dryer (120 ° C., 2 hours) was 38% by mass.

The obtained polyurethane has a structural unit represented by the following formula (16).

In the formula, x4 + y4 = 1, x4 = 0.83, and y4 = 0.17. n ₉ is a positive integer, is approximately 17 from the value of the weight-average molecular weight.

The actually measured value of the acid value of the solid content of the obtained polyurethane solution having a carboxyl group was 85 mgKOH / g, and the weight average molecular weight was 9.4 × 10 ³ .

Example 8
(Synthesis of polyurethane silver salt PU-5Ag ₁ )
2.00 g of a polyurethane solution having a carboxyl group obtained in Synthesis Example 5 (containing a carboxyl group equivalent to 1.3 mmol) was dissolved in 20 ml of acetone (manufactured by Wako Pure Chemical Industries, Ltd.), and sodium hydroxide ( A solution prepared by dissolving 0.05 g (1, 3 mmol) of Wako Pure Chemical Industries, Ltd. in 5 ml of water was added and stirred until uniform. A solution prepared by dissolving 0.23 g (1.3 mmol) of silver nitrate (manufactured by Wako Pure Chemical Industries, Ltd.) in 5 ml of water was added dropwise thereto to cause precipitation. After stirring at room temperature for 30 minutes, the supernatant was removed by decantation. In order to completely remove the remaining solvent, a silver salt of polyurethane was obtained by drying under reduced pressure for 1 hour using a vacuum dryer while heating at 100 ° C. (yield 0.56 g).

FIG. 13 shows the TG-DTA measurement result of the obtained polyurethane silver salt. The mass ratio of the residue after completion of the TG-DTA measurement was 20.6 mass%, which was a value close to 14.7 mass% of the theoretical silver content calculated from the molecular formula.

The obtained silver salt of the polyurethane has a structural unit represented by the following formula (17).

<Silver salt of polycarbonate diol-containing polyurethane>
Synthesis Example 6 (Synthesis of polyurethane PU-6)
To a 500 mL four-necked separable flask equipped with a dropping funnel, a stirrer, a thermocouple for temperature measurement, and a Liebig condenser, polycarbonate diol (weight average molecular weight 500, manufactured by Asahi Kasei Chemicals Corporation, DURANOL (registered trademark) T5650E as a diol compound 31.20 g (62 mmol, 0.45 equivalents relative to diisocyanate), and 11.41 g (77 mmol, 0.1 mol relative to diisocyanate) DMBA (manufactured by Huzhou Nagamori Chemical Co., Ltd.) as a dihydroxy compound having a carboxyl group. 55 equivalents) and 73.50 g of ethyl carbitol acetate (manufactured by Daicel Corporation) as a solvent was charged, and all raw materials were dissolved at 55 ° C. Using a dropping funnel, 30.96 g (139 mmol) of IPDI (manufactured by Sumika Bayer Urethane Co., Ltd., Desmodur (registered trademark) I) was added dropwise as a diisocyanate compound over 5 minutes. After completion of dropping, the temperature was raised to 110 ° C. over 1 hour, and then the reaction was continued at 110 ° C. for 5 hours. After confirming that the absorption spectrum of the isocyanate group observed at 2270 cm ⁻¹ in the infrared absorption spectrum almost disappeared, 0.19 g of isobutanol (manufactured by Wako Pure Chemical Industries, Ltd.) was added as a terminal blocking agent, and After reacting at 110 ° C. for 1 hour, it was allowed to cool to room temperature to obtain a polyurethane solution having a uniform carboxyl group. The solid content concentration determined by drying under reduced pressure using a vacuum dryer (drying at 120 ° C. for 5 hours and then drying at 135 ° C. for 1 hour) was 50% by mass.

The resulting polyurethane solution having a carboxyl group had an acid value of 62 mgKOH / g and a weight average molecular weight of 2.6 × 10 ⁴ in the solid content.

The obtained polyurethane has a structural unit represented by the following formula (18).

In the equation, x5 + y5 = 1, x5 = 0.55, and y5 = 0.45. n ₁₀ is a positive integer, is about 3 from the value of the weight average molecular weight. R ⁹ is an aliphatic hydrocarbon group having 5 or 6 carbon atoms.

(Synthesis of polyurethane silver salt PU-6Ag having silver atoms bonded to some or all of the carboxyl groups)
The polyurethane solution obtained in Synthesis Example 6 was reacted with silver oxide to obtain a silver salt in which silver atoms were bonded to part or all of the carboxyl groups. The ratio of silver salt was difficult to determine accurately by experimental methods such as IR spectrum measurement or NMR spectrum measurement or acid value titration, so that the added silver oxide was completely dissolved (= completely The value calculated from the raw material charge ratio was adopted after visually confirming that the reaction had occurred.

Example 9
(Synthesis of polyurethane silver salt PU-6Ag ₍₈₎ in which silver atoms are bonded to 8% of carboxyl groups)
4.01 g of the polyurethane solution having a carboxyl group obtained in Synthesis Example 6 (containing a carboxyl group corresponding to 2.10 mmol) was dissolved in 5.96 g of diethylene glycol monoethyl ether (manufactured by Junsei Kagaku Co., Ltd.). 0.02 g of silver oxide (manufactured by Wako Pure Chemical Industries, Ltd., 0.16 mmol as Ag) was added. The mixture was stirred at room temperature for 6 hours under light shielding, and it was confirmed that the silver oxide disappeared and became a uniform solution.

A part of the obtained polyurethane silver salt solution (solid content concentration: 21% by mass) was dried under reduced pressure for 2 hours using a vacuum dryer while heating at 120 ° C. TG-DTA measurement of the solid polyurethane silver salt obtained after drying was performed. The measurement results are shown in FIG. The mass ratio of the residue after completion of the TG-DTA measurement was 2.0 mass%, which was close to 0.8 mass%, which is the theoretical value of the silver content calculated from the molecular formula.

Example 10
(Synthesis of polyurethane silver salt PU-6Ag ₍₆₃₎ in which silver atoms are bonded to 63% of carboxyl groups)
2.06 g of the polyurethane solution having a carboxyl group obtained in Synthesis Example 6 (containing a carboxyl group corresponding to 1.08 mmol) was dissolved in 7.99 g of diethylene glycol monoethyl ether (manufactured by Junsei Chemical Co., Ltd.). 0.08 g of silver oxide (manufactured by Wako Pure Chemical Industries, Ltd., 0.68 mmol as Ag) was added. The mixture was stirred at room temperature for 6 hours under light shielding, and it was confirmed that the silver oxide disappeared and became a uniform solution.

A part of the obtained polyurethane silver salt solution (solid content concentration: 11% by mass) was dried under reduced pressure for 2 hours using a vacuum dryer while heating at 120 ° C. TG-DTA measurement of the solid silver salt obtained after drying was performed. The measurement results are shown in FIG. The mass ratio of the residue after completion of the TG-DTA measurement was 8.5 mass%, which was close to 6.4 mass%, which is the theoretical value of the silver content calculated from the molecular formula.

Example 11
(Synthesis of polyurethane silver salt PU-6Ag ₍₅₀₎ in which silver atoms are bonded to 50% of carboxyl groups)
8.00 g (containing a carboxyl group equivalent to 4.20 mmol) of the polyurethane solution having a carboxyl group obtained in Synthesis Example 6 was dissolved in 8.01 g of diethylene glycol monoethyl ether (manufactured by Junsei Chemical Co., Ltd.). Subsequently, 0.25 g of silver oxide (manufactured by Wako Pure Chemical Industries, Ltd., 2.10 mmol as Ag) was dispersed in 4.06 g of diethylene glycol monoethyl ether (manufactured by Junsei Chemical Co., Ltd.), and this dispersion was Added to the polyurethane solution. It stirred at 85 degreeC for 10 hours, and it confirmed that silver oxide disappeared and became a uniform solution.

A part of the obtained polyurethane silver salt solution (solid content concentration: 23% by mass) was dried under reduced pressure for 2 hours using a vacuum dryer while heating at 120 ° C. TG-DTA measurement of the solid silver salt obtained after drying was performed. The measurement results are shown in FIG. The mass ratio of the residue after completion of the TG-DTA measurement was 5.5% by mass, which was close to 5.1% by mass, which is the theoretical value of the silver content calculated from the molecular formula.

Example 12
(Synthesis of polyurethane silver salt PU-6Ag ₍₁₀₀₎ in which silver atoms are bonded to 100% of carboxyl groups)
8.00 g of a polyurethane solution having a carboxyl group obtained in Synthesis Example 6 (containing a carboxyl group corresponding to 4.20 mmol) was dissolved in 8.00 g of diethylene glycol monoethyl ether (manufactured by Junsei Chemical Co., Ltd.). Subsequently, 0.49 g of silver oxide (manufactured by Wako Pure Chemical Industries, Ltd., 4.20 mmol as Ag) was dispersed in 4.01 g of diethylene glycol monoethyl ether (manufactured by Junsei Kagaku Co., Ltd.). Added to the polyurethane solution. It stirred at 85 degreeC for 10 hours, and it confirmed that silver oxide disappeared and became a uniform solution.

A part of the obtained polyurethane silver salt solution (solid content concentration: 23% by mass) was dried under reduced pressure for 2 hours using a vacuum dryer while heating at 120 ° C. TG-DTA measurement of the solid silver salt obtained after drying was performed. The measurement results are shown in FIG. The mass ratio of the residue after completion of the TG-DTA measurement was 9.5 mass%, which was close to 10.2 mass%, which is the theoretical value of the silver content calculated from the molecular formula.

The resulting silver salt of polyurethane having silver atoms bonded to some or all of the carboxyl groups has a structural unit represented by the following formula (19).

In the equation, x6 + x7 + y5 = 1, and in Example 9, x6 = 0.04, x7 = 0.51, and y5 = 0.45. In Example 10, x6 = 0.35, x7 = 0.20, and y5 = 0.45. In Example 11, x6 = 0.275, x7 = 0.275, and y5 = 0.45. In Example 12, x6 = 0.55, x7 = 0, and y5 = 0.45. n ₁₀ is a positive integer, is about 3 from the value of the weight average molecular weight. R ⁹ is an aliphatic hydrocarbon group having 5 or 6 carbon atoms.

<Silver salt of polycarbonate diol-containing polyurethane in which DMBA is changed to DMPA (dimethylolpropionic acid)>
Synthesis Example 7 (Synthesis of polyurethane PU-7)
Polycarbonate diol (weight average molecular weight 500, manufactured by Asahi Kasei Chemicals Corporation, product name DURANOL T5650E) as a diol compound was added to a 500 mL four-necked separable flask equipped with a dropping funnel, a stirring device, a thermocouple for temperature measurement, and a Liebig condenser. 31.19 g (62 mmol, 0.45 equivalent to diisocyanate), 10.13 g (77 mmol, 0.55 equivalent to diisocyanate) of DMPA (manufactured by Tokyo Chemical Industry Co., Ltd.) as a dihydroxy compound having a carboxyl group, As a solvent, 72.40 g of ethyl carbitol acetate (manufactured by Daicel Corporation) was charged and heated to 55 ° C. Using a dropping funnel, 30.92 g (139 mmol) of IPDI (manufactured by Sumika Bayer Urethane Co., Ltd., Desmodur (registered trademark) I) was added dropwise as a diisocyanate compound over 10 minutes. After completion of the dropwise addition, the temperature was raised to 110 ° C. over 1 hour to completely dissolve DMPA, and then the reaction was continued at 110 ° C. for 5 hours. After confirming that the absorption spectrum of the isocyanate group observed at 2270 cm ⁻¹ in the infrared absorption spectrum almost disappeared, 0.22 g of isobutanol (manufactured by Wako Pure Chemical Industries, Ltd.) was added as a terminal blocking agent. After reacting at 110 ° C. for 1 hour, it was allowed to cool to room temperature to obtain a polyurethane solution having a uniform carboxyl group. The solid content concentration obtained by drying under reduced pressure using a vacuum dryer (drying at 120 ° C. for 4 hours) was 51% by mass.

The obtained polyurethane solution having a carboxyl group had an acid value of 59 mgKOH / g and a weight average molecular weight of 2.8 × 10 ⁴ .

The obtained polyurethane has a structural unit represented by the following formula (20).

In the equation, x8 + y6 = 1, x8 = 0.55, and y6 = 0.45. n ₁₁ is a positive integer, is about 3 from the value of the weight average molecular weight. R ¹⁰ is an aliphatic hydrocarbon group having 5 or 6 carbon atoms.

Example 13
(Synthesis of polyurethane silver salt PU-7Ag)
8.00 g of the polyurethane solution having a carboxyl group obtained in Synthesis Example 7 (containing a carboxyl group corresponding to 4.20 mmol) was dissolved in 7.99 g of diethylene glycol monoethyl ether (manufactured by Junsei Chemical Co., Ltd.). Subsequently, 0.49 g of silver oxide (manufactured by Wako Pure Chemical Industries, Ltd., 4.20 mmol as Ag) was dispersed in 4.00 g of diethylene glycol monoethyl ether (manufactured by Junsei Chemical Co., Ltd.). Added to the polyurethane solution. It stirred at 85 degreeC for 5 hours, and it confirmed that silver oxide disappeared and became a uniform solution.

A part of the obtained polyurethane silver salt solution (solid content concentration: 23% by mass) was dried under reduced pressure for 2 hours using a vacuum dryer while heating at 100 ° C. TG-DTA measurement of the solid silver salt obtained after drying was performed. The measurement results are shown in FIG. The mass ratio of the residue after completion of the TG-DTA measurement was 9.4 mass%, which was close to 10.3 mass%, which is the theoretical value of the silver content calculated from the molecular formula.

The obtained silver salt of polyurethane has a structural unit represented by the following formula (21).

Synthesis Example 8 <Silver salt of polyurethane containing polyethylene glycol 1000>
(Synthesis of polyurethane PU-8)
In a 500 mL four-necked separable flask equipped with a dropping funnel, a stirrer, a thermocouple for temperature measurement, and a Liebig condenser, 62.72 g of polyethylene glycol 1000 (weight average molecular weight 1000, manufactured by NOF Corporation) as a diol compound ( 62 mmol, 0.45 equivalents relative to diisocyanate), 11.41 g (77 mmol, 0.55 equivalents relative to diisocyanate) DMBA (manufactured by Huzhou Nagamori Chemical Co., Ltd.) as a dihydroxy compound having a carboxyl group, and as a solvent 105.05 g of ethyl carbitol acetate (manufactured by Daicel Corporation) was charged, and all raw materials were dissolved at 55 ° C. Using a dropping funnel, 30.91 g (139 mmol) of IPDI (manufactured by Sumika Bayer Urethane Co., Ltd., Desmodur (registered trademark) I) was added dropwise as a diisocyanate compound over 5 minutes. After completion of dropping, the temperature was raised to 110 ° C. over 1 hour, and then the reaction was continued at 110 ° C. for 5 hours. After confirming that the absorption spectrum of the isocyanate group observed at 2270 cm ⁻¹ in the infrared absorption spectrum almost disappeared, 0.17 g of isobutanol (manufactured by Wako Pure Chemical Industries, Ltd.) was added as an end-capping agent. After reacting at 110 ° C. for 1 hour, it was allowed to cool to room temperature to obtain a polyurethane solution having a uniform carboxyl group. The solid content concentration determined by drying under reduced pressure using a vacuum dryer (drying at 120 ° C. for 1 hour) was 51% by mass.

The obtained polyurethane solution having a carboxyl group had an acid value of 42 mgKOH / g and a weight average molecular weight of 1.5 × 10 ⁴ .

The obtained polyurethane has a structural unit represented by the following formula (22).

In the equation, x9 + y7 = 1, x9 = 0.55, and y7 = 0.45. n ₁₂ is a positive integer, is approximately 22 from the value of the weight-average molecular weight.

Example 14
(Synthesis of polyurethane silver salt PU-8Ag (TP) using terpineol as reaction solvent)
2.01 g (containing 0.73 mmol of carboxyl group) of the polyurethane solution having a carboxyl group obtained in Synthesis Example 8 was dissolved in 8.00 g of terpineol C (manufactured by Nippon Terpene Chemical Co., Ltd.). 08 g of silver oxide (manufactured by Wako Pure Chemical Industries, Ltd., 0.73 mmol as Ag) was added. The mixture was stirred at room temperature for 6 hours under light shielding, and it was confirmed that the silver oxide disappeared and became a uniform solution.

A part of the obtained polyurethane silver salt solution (solid content concentration: 11% by mass) was dried under reduced pressure for 2 hours using a vacuum dryer while heating at 100 ° C. TG-DTA measurement of the solid silver salt obtained after drying was performed. The measurement results are shown in FIG. The mass ratio of the residue after completion of the TG-DTA measurement was 7.7 mass%, which was close to 7.4 mass%, which is the theoretical value of the silver content calculated from the molecular formula.

The obtained silver salt of the polyurethane has a structural unit represented by the following formula (23).

Example 15
(Synthesis of polyurethane silver salt PU-8Ag (ECA / EC) using ECA / EC as a reaction solvent)
Dissolve 2.01 g of the polyurethane solution having a carboxyl group obtained in Synthesis Example 8 (containing a carboxyl group equivalent to 0.73 mmol) in 8.00 g of diethylene glycol monoethyl ether (manufactured by Junsei Kagaku Co., Ltd.). 0.08 g of silver oxide (manufactured by Wako Pure Chemical Industries, Ltd., 0.73 mmol as Ag) was added. The mixture was stirred at room temperature for 7 hours under light shielding, and it was confirmed that the silver oxide disappeared and became a uniform solution.

The obtained polyurethane silver salt solution was dried under reduced pressure while heating by the method shown in Example 14, and TG-DTA measurement of the solid silver salt obtained after drying was performed. Similar results were obtained.

Example 16
(Synthesis of polyurethane copper salt PU-8Cu using copper hydroxide)
4.02 g (containing a carboxyl group corresponding to 1.46 mmol) of the polyurethane solution having a carboxyl group obtained in Synthesis Example 8 was dissolved in 15.99 g of diethylene glycol monoethyl ether (manufactured by Junsei Kagaku Co., Ltd.). 0.07 g of copper hydroxide (manufactured by Wako Pure Chemical Industries, Ltd.) (0.73 mmol) was added. After heating to 120 ° C. in an oil bath, the mixture was stirred for 6 hours, and it was confirmed that copper hydroxide had disappeared and became a uniform solution.

A part of the obtained polyurethane copper salt solution (solid content concentration 11% by mass) was dried under reduced pressure for 2 hours using a vacuum dryer while heating at 120 ° C. TG-DTA measurement of the solid silver salt obtained after drying was performed. The measurement results are shown in FIG. The mass ratio of the residue after completion of the TG-DTA measurement was 3.2 mass%, which was close to 2.3 mass%, which is the theoretical value of the copper content calculated from the molecular formula.

The obtained copper salt of the polyurethane has a crosslinked structure as shown in the above formula (9).

(Silver salt of polyethylene glycol 1000-containing polyurethane using MDI as diisocyanate)
Synthesis Example 9 (Synthesis of polyurethane PU-9)
In a 500 mL four-necked separable flask equipped with a dropping funnel, a stirrer, a thermocouple for temperature measurement, and a Liebig condenser, 62.68 g of polyethylene glycol 1000 (weight average molecular weight 1000, manufactured by NOF Corporation) as a diol compound ( 62 mmol, 0.45 equivalents relative to diisocyanate), 11.41 g (77 mmol, 0.55 equivalents relative to diisocyanate) DMBA (manufactured by Huzhou Nagamori Chemical Co., Ltd.) as a dihydroxy compound having a carboxyl group, and as a solvent 108.90 g of ethyl carbitol acetate (manufactured by Daicel Corporation) was charged, and all raw materials were dissolved at 55 ° C. Using a dropping funnel, 34.82 g (139 mmol) of MDI (manufactured by BASF INOAC Polyurethane Co., Ltd., product name Luplanate (registered trademark) MI) was added dropwise as a diisocyanate compound over 30 minutes. After completion of dropping, the temperature was raised to 110 ° C. over 2 hours, and then the reaction was continued at 110 ° C. for 4 hours. After confirming that the absorption spectrum of the isocyanate group observed at 2270 cm ⁻¹ in the infrared absorption spectrum almost disappeared, 0.17 g of isobutanol (manufactured by Wako Pure Chemical Industries, Ltd.) was added as an end-capping agent. After reacting at 110 ° C. for 1 hour, it was allowed to cool to room temperature to obtain a polyurethane solution having a uniform carboxyl group. The solid content concentration determined by drying under reduced pressure using a vacuum dryer (drying at 120 ° C. for 1 hour) was 50% by mass.

The obtained polyurethane solution having a carboxyl group had an acid value of 43 mgKOH / g and a weight average molecular weight of 2.0 × 10 ⁴ in a solid content.

The obtained polyurethane has a structural unit represented by the following formula (24).

In the formula, x10 + y8 = 1, x10 = 0.55, and y8 = 0.45. n ₁₃ is a positive integer, is approximately 22 from the value of the weight-average molecular weight.

Example 17
(Synthesis of polyurethane silver salt PU-9Ag ₍₅₀₎ in which silver atoms are bonded to 50% of carboxyl groups)
8.00 g of the polyurethane solution having a carboxyl group obtained in Synthesis Example 9 (containing a carboxyl group corresponding to 2.85 mmol) was dissolved in 8.00 g of diethylene glycol monoethyl ether (manufactured by Junsei Chemical Co., Ltd.). Subsequently, 0.17 g of silver oxide (manufactured by Wako Pure Chemical Industries, Ltd., 1.43 mmol as Ag) was dispersed in 4.00 g of diethylene glycol monoethyl ether (manufactured by Junsei Chemical Co., Ltd.), and this dispersion was Added to the polyurethane solution. It stirred at 85 degreeC for 3 hours, and it confirmed that silver oxide disappeared and became a uniform solution.

The obtained silver salt of polyurethane has a structural unit represented by the following formula (25).

In the formula, x11 + x12 + y9 = 1, x11 = 0.275, x12 = 0.275, and y9 = 0.45. n ₁₃ is a positive integer, is approximately 22 from the value of the weight-average molecular weight.

<Conductive pattern formation 1>
Using AgC239 (flat shape, D ₅₀ = 2.3 μm, thickness 0.67 μm) manufactured by Fukuda Metal Foil Industry Co., Ltd. as the silver particles, the components and the mixing ratios shown in Table 1 (parts by mass [g]) were rotated.・ Remixing mixer Awatori Nertaro (manufactured by Shinky Co., Ltd.) was mixed under normal temperature and normal pressure (rotation 600 rpm, revolution 1200 rpm for 3 minutes 3 times), 10 g of conductive paste (composition for conductive pattern formation) Was prepared. In addition, the used solvent (dispersion medium) is Daicel Corporation's ethyl carbitol acetate (ECA) and Daicel Corporation's ethyl carbitol (EC). Using the obtained conductive paste, polyimide film (product name: Kapton (registered trademark) 150EN-C, Toray DuPont Co., Ltd.) so that it becomes a 2 cm × 2 cm square pattern with a film thickness of 10 μm or more by screen printing. Printed on). After the ink pattern was formed, using a dryer VO-420 (manufactured by Advantech Co., Ltd.), it was fired at 140 ° C. in air for the time shown in Table 1 to form a conductive pattern.

<Performance evaluation 1>
(1) Volume resistivity After measuring the film thickness of the said conductive pattern with the micrometer, the surface resistance of the conductive pattern was measured with the resistivity meter Loresta GP (made by Mitsubishi Chemical Analytech Co., Ltd.) based on the 4-terminal method. The ESP mode was used for the measurement mode and the terminals used. The obtained film thickness was multiplied by the surface resistance to obtain the volume resistivity of the thin film. The results are shown in Table 1.

As shown in Table 1, when the firing time and the used polyurethane having the carboxyl group are the same, the polyurethane having a carboxyl group in which all or a part of the carboxyl group is a metal salt (silver salt or copper salt). The Example Evaluation Examples 1 to 19 used have a lower volume resistivity than the Comparative Evaluation Examples 1 to 11 using a polyurethane having a carboxyl group which is not a metal salt. In addition, when a part of the carboxyl group is a metal salt, it is understood that the volume resistivity is further decreased as the ratio of the metal salt is increased. From this, the conductive paste using the polyurethane which has the carboxyl group in which all or one part of the carboxyl group concerning the Example became a metal salt is the conductive paste using the polyurethane which has the carboxyl group which is not a metal salt It can be seen that the conductivity of the conductive pattern can be improved with lower sintering energy. In the examples, the amount of metal atoms in the metal (silver or copper) salt of polyurethane, which is a binder resin, is larger than the metal atom comparative example, but the amount is 100 parts by mass of metal particles. Therefore, the influence on the change in conductivity is almost negligible.

(2) Adhesiveness In addition to the above-described volume resistivity, as a characteristic required for a conductive pattern, there is an adhesiveness with a substrate. Therefore, the adhesion between the conductive pattern and the substrate was evaluated by the method shown below.

Using the cutter knife and cross cut guide CCJ-1 (Cortech Co., Ltd.), 11 cuts were made in the conductive pattern at intervals of 1 mm, and then the 90 ° direction was changed and another 11 pieces were drawn to obtain 100 1 mm pieces. A square cell was formed. A cellophane adhesive tape was attached so as to adhere to the cut printed surface, and the cellophane adhesive tape was rubbed to adhere the tape to the coating film. One to two minutes after the tape was attached, the tape was held at a right angle to the printed surface and peeled off instantaneously. The number of squares peeled off was defined as cross-cut peeling. The results are shown in Table 1.

As shown in Table 1, even when all or part of the carboxyl groups in the polyurethane having carboxyl groups is a metal salt (silver salt or copper salt), the cross-cut peeling remains 0, It can be seen that the sex is maintained. From this, the conductive paste using the polyurethane which has the carboxyl group in which all or a part of the carboxyl groups according to the examples are metal salts has two characteristics required for the conductive pattern, ie, volume resistivity and adhesion. It can be seen that both are well balanced.

<Conductive pattern formation 2 and performance evaluation 2>
Next, a conductive paste was prepared in which the sum of the silver amount derived from the silver salt and the silver amount derived from the particles was made constant, and the performance was evaluated. The conductive pattern formation and performance evaluation methods were the same as in the conductive pattern formation 1 and performance evaluation 1, and the results of baking at 120 ° C. and 170 ° C. were further added.

As shown in Table 2, when the firing conditions and the polyurethane skeleton are the same, Examples 1 to 21 in which all or part of the carboxyl groups are silver salts are comparative evaluation examples that are not silver salts. It can be seen that the volume resistivity is lower than that of 1 to 18 without deteriorating the adhesion. In addition, as shown in Examples 1 to 9 and Comparative Evaluations 1 to 6, the volume resistivity is further decreased as the ratio of silver chloride of the carboxyl group is increased. It can be confirmed again that it originates from the part. Thus, even when the amount of silver derived from the silver salt and the amount of silver derived from the particles are made constant, the same result as in the performance evaluation can be obtained, so the improvement in conductivity is simply due to the increase in the amount of silver in the paste. It became clear that it was not.

<Conductive pattern formation 3 / performance evaluation 3>
Subsequently, a conductive paste using silver particles other than AgC239 was produced. The formation method of a conductive pattern and the evaluation method of performance used the method similar to the said conductive pattern formation 1 and the performance evaluation 1. The newly used silver particles were AgC-A (flat shape, D ₅₀ = 3.1 μm, thickness 0.90 μm) and AgC-201Z (flat shape, D ₅₀ = 2.6 μm, thickness) manufactured by Fukuda Metal Foil Powder Co., Ltd. 0.76 μm).

As shown in Table 3, when the baking conditions and the polyurethane skeleton are the same, Examples 1 to 12 in which all or part of the carboxyl groups are silver salts are comparative evaluation examples that are not silver salts. It can be seen that the volume resistivity is lower than that of 1 to 12 without impairing the adhesion. As described above, even when silver particles other than AgC239 are used, the same results as in the performance evaluation can be obtained. Therefore, the effect of improving the conductivity is not limited to the case where specific particles are used. It was shown that a polyurethane silver salt of the present invention is applicable to a wide range.

<Conductive pattern formation 4 Composition for conductive pattern formation using silver nanoparticles>
DF-AT-5100 manufactured by DOWA Electronics Co., Ltd. (spherical, the average value of the primary particle diameter is 40 nm) is used as the silver particles, and the rotation and revolution of each component and blending ratio (part by mass [g]) shown in Table 4 Mixing under normal temperature and normal pressure using mixer Awatori Nertaro (manufactured by Sinky Co., Ltd.) (spinning 600 rpm, revolution 1200 rpm for 3 minutes three times) to prepare 10 g of conductive paste (conductive pattern forming composition) did. In addition, the solvent used is Daicel Corporation's ethyl carbitol acetate (ECA), Daicel Corporation's ethyl carbitol (EC), and Nippon Terpene Chemical Co., Ltd. Tersolve MTPH. Using the obtained conductive paste, printing was performed on non-alkali glass (product name Eagle XG, manufactured by Corning) so as to form a 2 cm × 2 cm square pattern with a film thickness of about 1 μm by screen printing. After forming the ink pattern, using a dryer VO-420 (manufactured by Advantech Co., Ltd.), heat conduction was performed in air at 200 ° C. for 1 hour to form a conductive pattern.

<Performance evaluation 4>
(1) Volume resistivity Since the film thickness of the conductive pattern was thinner than the measurable range of a micrometer, it was measured with a stylus type surface shape measuring device DEKTAK-6M (manufactured by Bruker Nano). The surface resistance of the conductive pattern was measured with a resistivity meter Loresta GP (manufactured by Mitsubishi Chemical Analytech Co., Ltd.) based on the 4-terminal method, and the measurement mode and the terminals used were measured using the ESP mode. The obtained film thickness was multiplied by the surface resistance to obtain the volume resistivity of the thin film. The results are shown in Table 4.

(2) Adhesiveness It evaluated by the method similar to the said performance evaluation 1. The results are shown in Table 4.

As shown in Table 4, when the firing conditions and the polyurethane skeleton are the same, the volume resistivity is lower in the example of the evaluation example without losing the adhesion than in the comparative evaluation example, as in the above evaluation results. I understand that. From this result, it was shown that the polyurethane silver salt of the present invention exhibits the effect of improving the conductivity not only when combined with micron-sized silver particles but also when combined with nano-sized silver particles.

<Conductive pattern formation 5 Composition for conductive pattern formation using silver nanowire>
Using silver nanowire as a conductive component, mixing at each component and mixing ratio (parts by mass [g]) shown in Table 5 under normal temperature and normal pressure using a rotating / revolving mixer Awatori Neritarou (Sinky Corp.) Then, 10 g of conductive paste (composition for forming a conductive pattern) was prepared (3 times for 3 minutes at 600 rpm for rotation and 1200 rpm for revolution). Silver nanowires synthesized by the polyol method (average length 20 μm, average diameter 35 nm) were used, and terpineol C and tersolve MTPH (both manufactured by Nippon Terpene Chemical Co., Ltd.) were used as the solvent. Printing and baking are possible even when only polyurethane and polyurethane silver salt are used as the binder resin, but polyvinyl pyrrolidone K-90 (manufactured by BASF) was used in combination in order to keep the pattern shape after baking better. Using the obtained conductive paste, printing was performed on a PET film (Lumirror (registered trademark) 125T60, manufactured by Toray Industries, Inc.) so as to form a 2 cm × 2 cm square pattern by screen printing. After the ink pattern was formed, using a dryer VO-420 (manufactured by Advantech Co., Ltd.), heat conduction was performed at a temperature shown in Table 1 for 1 hour in the air to form a conductive pattern.

<Performance evaluation 5>
Since silver nanowire is a material used as a transparent conductive film for touch panels, and the value of surface resistance is more important than volume resistivity in evaluating the transparent conductive film, only the surface resistance was evaluated. The measuring device was a resistivity meter Loresta GP (manufactured by Mitsubishi Chemical Analytech Co., Ltd.) based on the four-terminal method, and the measuring mode and terminals used were ESP mode. The results are shown in Table 5.

As shown in Table 5, when the firing conditions and the polyurethane skeleton are the same, it can be seen that the surface resistance is lower in the practical evaluation example than in the comparative evaluation example, as in the above evaluation results. From this result, it was shown that the polyurethane silver salt of the present invention exhibits the effect of improving the conductivity even when combined with silver nanowires.

Claims

A polyurethane having a carboxylate metal salt moiety represented by (COO) n M in a polymer skeleton (M is a metal atom selected from metals belonging to Group 11 of the periodic table, and n is a valence of metal atom M) A binder resin for conductive compositions, comprising:
2. The binder resin for an electrically conductive composition according to claim 1, wherein the polyurethane includes a urethane bond unit of (a1) a polyisocyanate compound and (a2) a dihydroxy compound having a carboxyl group in a structural unit.
The binder resin for conductive compositions according to claim 1 or 2, wherein the metal constituting the metal salt is either silver or copper.
The binder for conductive compositions according to claim 2 or 3, wherein the (a2) dihydroxy compound having a carboxyl group is at least one of 2,2-dimethylolpropionic acid and 2,2-dimethylolbutanoic acid. resin.
The binder resin for conductive compositions according to any one of claims 2 to 4, wherein the (a1) polyisocyanate compound is an alicyclic polyisocyanate.
6. The alicyclic polyisocyanate is 3-isocyanate methyl-3,3,5-trimethylcyclohexane (IPDI, isophorone diisocyanate) or bis- (4-isocyanatocyclohexyl) methane (hydrogenated MDI). Binder resin for conductive composition.
Binder resin (A) for conductive composition according to any one of claims 1 to 6,
A conductive material (B);
A solvent (C) for dissolving the binder resin (A) for the conductive composition;
A composition for forming a conductive pattern.
The conductive material (B) is metal particles (B1), and the ratio of the metal particles (B1) to the entire conductive pattern forming composition is 20% by mass to 95% by mass, and the binder resin for the conductive composition is dissolved. The content of the solvent (C) is 5 mass% to 80 mass%, and the binder resin for conductive composition (A) is 1 mass part to 15 mass parts with respect to 100 mass parts of the metal particles (B1). The composition for conductive pattern formation of Claim 7.
The conductive material (B) is a metal nanowire and / or metal nanotube (B2), and the ratio of the metal nanowire and / or metal nanotube (B2) to the whole composition for forming a conductive pattern is 0.01% by mass to 10% by mass, the content of the solvent (C) for dissolving the binder resin for conductive composition is 90% by mass or more, and the binder resin for conductive composition (A) is a metal nanowire and / or metal nanotube (B2) The composition for forming a conductive pattern according to claim 7, wherein the composition is 10 to 400 parts by mass with respect to 100 parts by mass.
The conductive pattern forming composition according to claim 7, wherein the metal salt and the metal constituting the conductive material (B) are either silver or copper.
A polyurethane containing at least one of structural units represented by the following formula (1).