KR101927766B1

KR101927766B1 - Metal nanoparticle-protecting polymer and metal colloidal solution, and method for producing the same

Info

Publication number: KR101927766B1
Application number: KR1020157023902A
Authority: KR
Inventors: 승택 이; 종우 야오
Original assignee: 디아이씨 가부시끼가이샤
Priority date: 2013-04-24
Filing date: 2013-04-24
Publication date: 2018-12-12
Also published as: TW201441305A; WO2014172856A1; CN105164183A; CN105164183B; KR20150114552A; TWI613255B; JP5811430B2; JP2015525250A; KR20170040368A

Abstract

Metal nanoparticle protection capable of manifesting more practical conductivity by intentionally adding and controlling plural properties such as good metal nanoparticle control ability, high dispersion stability, good low-temperature plasticity, and easy purification and separation of metal nanoparticles Polymers, metal colloid solutions, and methods of making them. Specifically, it is characterized by having a polyacetylalkyleneimine segment in which 5 to 100 mol% of a primary amine in a polyalkyleneimine and 0 to 50 mol% of a secondary amine are acetylated in one molecule and a hydrophilic segment , A process for producing the metal nanoparticle protective polymer, and a metal colloid solution formed by dispersing a metal nanoparticle-containing complex comprising the same as a protective agent in a medium, and a process for producing the same.

Description

FIELD OF THE INVENTION [0001] The present invention relates to a metal nanoparticle-protecting polymer, a metal colloid solution,

The present invention relates to a metal colloid solution using a polymer containing an acetylated polyalkyleneimine segment and a hydrophilic segment or a polymer containing a hydrophobic segment in addition thereto as a protective agent for metal nanoparticles, Polymer and a method for producing the same.

The metal nanoparticles are nanoparticles having a particle size of 1 to several hundred nanometers, and the specific surface area thereof is remarkably large. Therefore, the metal nanoparticles are attracting attention in various fields. They are widely used as electronic materials, catalysts, magnetic materials, optical materials, various sensors, And applications are expected.

Although manufacturing of a printed wiring board or a semiconductor device is performed only through a photolithographic process, it has a troublesome multi-step manufacturing process. Therefore, metal nanoparticles, which are being developed in recent years, , Attention has been focused on a manufacturing technology of a coating type electronic device in which this is patterned by various printing methods and knitted as a device.

Although this technique is referred to as printed electronics, this method has the potential to mass-produce electronic circuit patterns or semiconductor devices in a roll-to-roll manner, on demand, Economical efficiency by economizing is expected and it is anticipated that it will develop into an inexpensive manufacturing method such as a display device, a light emitting device, and an IC tag (RFID). As the conductive material ink used in the printed electronics, a conductive ink composed of metallic nano-particles such as gold, silver, platinum and copper can be used. However, in view of economical efficiency and ease of handling, .

When the metal of the silver nanoparticles is reduced to nano-size, the specific surface area is significantly higher than that of the bulk silver and the surface energy is increased. Therefore, there is a strong tendency to decrease the surface energy by mutual fusion. As a result, the particles mutually melt at a temperature much lower than the melting point of the bulk silver. This is sometimes referred to as a quantum size effect (parasitic effect), but there is merit in that silver nanoparticles are used as a conductive material. On the other hand, the ease of fusion between the metal nanoparticles damages the stabilization of the metal nanoparticles and deteriorates the storage stability. Therefore, in order to stabilize the metal nanoparticles, it is necessary to protect the metal nanoparticles with a protective agent .

Generally, nanomaterials (compounds having a size in the order of nanometers) tend to be expensive because they are manufactured through a special process due to their size, which is a cause for impeding the diffusion of nanomaterials. In order to manufacture the metal nanoparticles at a low cost, a liquid-phase reduction method which does not require a special apparatus such as a vacuum process is advantageous. The liquid-phase reduction method is a method in which a metal compound is reacted with a reducing agent in a solvent to reduce the metal nanoparticles to obtain metal nanoparticles. At this time, in order to control the shape and the particle diameter of the produced metal nanoparticles and to form a stable dispersion state, Discloses a technique for performing reduction in the presence of a compound, which is also referred to as a protecting agent. The protective agent is often a polymer compound designed to have a functional group capable of coordinating to metal particles such as a tertiary amino group, a quaternary ammonium group, a heterocyclic ring having a basic nitrogen atom, a hydroxyl group, and a carboxyl group (for example, Patent Document 1).

As described above, in order to produce metal nanoparticles that are expected to exhibit a favorable low-temperature fusion bonding phenomenon, a protective agent capable of obtaining appropriate metal nanoparticle shape, particle diameter, dispersion stability, and the like is used. However, since the protective agent deteriorates the conductive performance as a resistance component for the fused bulk metal, it is preferable that the protective agent has good low-temperature baking ability (the resistivity obtained by baking the thin film coated with the conductive ink containing metal nanoparticles at 100 to 150 캜 this, ^10-6 Ωcm performance, indicating the order) is more difficult to discard this expression has a problem. Thus, from the viewpoint of the design of the conductive material, the protective agent is not limited to the ability to produce small particles, the ability to stably disperse the particles, and the ability of metal nano- And from the viewpoint of production of metal nanoparticles, it is necessary to simultaneously provide a plurality of properties such as the ability to easily purify and separate the produced metal nanoparticles. As such a protective agent, it is possible to use a commercially available polymer pigment dispersing agent such as Solsperse (Geneca) or fluorene (Kyoeisha Gakusha) or a pigment-affinity group (amine) as a main chain / side chain, Further, there is provided a technique of using a polymer having a plurality of solvated portions or a polymer of a copolymer having a polyethyleneimine portion and a polyethylene oxide portion, but it is difficult to realize them at the same time and further improvement is required See, for example, Patent Documents 2 to 4).

Japanese Patent Application Laid-Open No. 2004-346429 Japanese Patent Application Laid-Open No. 11-080647 Japanese Patent Application Laid-Open No. 2006-328472 Japanese Patent Laid-Open No. 2008-037884

A problem to be solved by the present invention is to intentionally add and control a plurality of properties such as good metal nanoparticle control ability, high dispersion stability, good low-temperature plasticity, and easy purification and separation of metal nanoparticles, A metal colloid solution, and a method for producing the same.

The present inventors have found that a two-component polymer in which a polyalkyleneimine segment containing a polyethyleneimine and a hydrophilic segment containing a polyoxyalkylene chain are bonded together, or a ternary polymer in which a hydrophobic segment such as an epoxy resin is bonded to the above- (Patent Document 4 and the like). However, this technique does not have the above-mentioned performance at a high level. As a result of further investigation, it has been found that it is effective to use a polymer obtained by acetylating the nitrogen atom in the polyalkyleneimine segment And have accomplished the present invention.

That is, the present invention relates to a polyacetylalkyleneimine segment (A) obtained by acetylating 5 to 100 mol% of a primary amine and 0 to 50 mol% of a secondary amine in a molecule, (B), a process for producing the metal nanoparticle protective polymer, and a metal colloid solution formed by dispersing the metal nanoparticle-containing complex comprising the same as a protective agent in a medium, and a method for producing the same.

The metal colloid solution obtained in the present invention exhibits good low-temperature plasticity. The good conductivity at such a low temperature is due to the fact that the protective polymer used in the present invention is easily removed from the surface of the metal nanoparticles at a low temperature. In addition, the metal nanoparticles obtained in the presence of the specific protective polymer have a sufficiently small particle size, a monodispersed particle diameter, a narrow particle size distribution, and a good storage stability. This is because the acetylalkyleneimine structure moiety in the protective polymer preferably protects the metal nanoparticles and the dispersibility in the medium is expressed by the hydrophilic segment or the hydrophobic segment in the polymer, And maintain stable dispersion state in the solvent for a long period without damaging it.

In the present invention, in the case of producing the metal colloid solution, the metal nanoparticles are obtained by reduction, and in the purification separation step for removing the impurities, a dispersion of the resulting composite of the metal nanoparticles and the protective polymer The complex is easily separated by the simple operation of adding a poor solvent. However, this is due to a strong association force of the protective polymer, and it is necessary to set a complicated process or a precise condition It is highly advantageous as an industrial production method.

Further, the metal nanoparticles in the metal colloid solution obtained in the present invention can be used as a metal nanoparticle having a large specific surface area, a high surface energy, a plasmon absorption and the like, a dispersion stability of a self-organizing polymer dispersion, Electrical properties, and stability, and is capable of efficiently exhibiting properties such as conductivity, and has various chemical, electrical, and magnetic properties required for conductive pastes and the like, and is applicable to various fields such as catalysts, electronic materials, magnetic materials, It can be applied to various sensors, color materials, medical examination applications, and the like.

The metal nanoparticle protective polymer of the present invention is characterized by comprising a polyacetyl alkyleneimine segment (A) formed by acetylating 5 to 100 mol% of a primary amine and 0 to 50 mol% of a secondary amine in a polyalkyleneimine, (B), or a polymer compound having the polyacetyl alkyleneimine segment (A), the hydrophilic segment (B) and the hydrophobic segment (C). The dispersion (metal colloid solution) of the metal nanoparticles protected with the protective polymer having such a structure is excellent in dispersion stability and conductivity characteristics and has a variety of metal-containing functional groups such as coloring, catalyst, And has an ability as a dispersion body.

In the polyacetylalkyleneimine segment (A) formed by acetylation in the specific range of the protective polymer in the present invention, since the acetylalkyleneimine unit in the segment can be coordinatively bonded to the metal or metal ion, It is a segment that can be fixed. In the case where the composite in which the metal nanoparticles obtained in the present invention are protected by the protective polymer is prepared or preserved in a hydrophilic solvent, the polyacetylalkyleneimine segment (A) and the hydrophilic segment (B) , It is possible to exhibit particularly excellent dispersion stability and storage stability in the resulting metal colloid solution.

From the viewpoint of an industrial production method, a simple purification separation method of a complex obtained by dissolving or dispersing a metal compound in a medium and reducing the resulting metal nano-particle by the protective polymer is important. It is preferable to employ a method of adding acetone or the like and precipitating and separating. Since the acetylalkyleneimine unit of the protective polymer of the present invention has a function of promoting the association of the metal nanoparticle-containing complexes rapidly in a poor solvent environment because of its high polarity, it is easy to precipitate Separate.

Further, in the sintering process after the metal colloid solution itself, which is a dispersion of the metal nanoparticle-containing complex, or the conductive material obtained by adjusting this solution with the conductive ink, is printed or applied onto the substrate, the acetyl alkyleneimine unit Is weak in coordination bonding with metals, so that it can be easily decoupled from the surface of metal nanoparticles even at a low temperature, and as a result, good low-temperature plasticity is exhibited.

The particle diameter of the dispersion (composite) in the metal colloid solution of the present invention is not limited only to the molecular weight of the protective polymer used and the degree of polymerization of the polyacetylalkyleneimine segment (A), but also to the respective components constituting the protective polymer , The hydrophilic segment (B) described later, and the hydrophobic segment (C) to be described later, as well as the composition and composition ratio of the polyacetylalkyleneimine chain (A).

The degree of polymerization of the polyacetylalkyleneimine segment (A) is not particularly limited, but if it is too low, the protective ability of the metal nanoparticles as a protective polymer may become insufficient in some cases. If too high, the metal nanoparticles and the protective polymer The particle diameter of the composite particles may become large, which may interfere with the storage stability. Therefore, in order to make the metal nanoparticles immobilized and the ability to prevent the dispersion particles from becoming larger, the number of alkyleneimine units (degree of polymerization) of the polyacetylalkyleneimine segment (A) is usually from 1 to 10,000 , Preferably in the range of 5 to 2,500, and most preferably in the range of 5 to 300.

The polyacetylalkyleneimine segment (A) is easily obtained by acetylating an alkyleneimine moiety in a polyalkyleneimine segment in the precursor structure, and specifically, it can be obtained by a reaction with an acetylating agent. The segment comprising the polyalkyleneimine is not particularly limited as long as it is commercially available or can be synthesized. However, it is preferably a branched polyethyleneimine or a branched polypropyleneimine in view of industrial availability and the like, And is preferably made of a vapor-phase polyethyleneimine.

When a hydrophilic medium such as water is used as the metal colloid solution, the hydrophilic segment (B) constituting the protective polymer of the present invention is preferably a segment having high affinity with a solvent and maintaining storage stability of the colloid solution to be. When a hydrophobic solvent is used, the hydrophilic segment (B) has a role of forming a core of the dispersion particles by a strong cohesive force in the molecule or intermolecular interactions of the hydrophilic segment (B). The degree of polymerization of the hydrophilic segment (B) is not particularly limited. However, when a hydrophilic solvent is used, the storage stability may deteriorate when the degree of polymerization is too low, and may aggregate when the degree of polymerization is too high. In the case of using a hydrophobic solvent , If the degree of polymerization is too low, the aggregation force of the dispersion particles becomes insufficient, and if it is too high, the affinity with the solvent can not be maintained. From these viewpoints, the degree of polymerization of the hydrophilic segment (B) is usually from 1 to 10,000, preferably from 3 to 3,000, and more preferably from 5 to 1,000 from the viewpoint of ease of production. When the hydrophilic segment is a polyoxyalkylene chain, the degree of polymerization is particularly preferably from 5 to 500.

The hydrophilic segment (B) is not particularly limited as long as it is a commercially available or synthetic hydrophilic polymer chain. Particularly, when a hydrophilic solvent is used, it is preferable that it is made of a nonionic polymer because a colloidal solution having excellent stability can be obtained.

Examples of the hydrophilic segment (B) include polyoxyalkylene chains such as polyoxyethylene chain and polyoxypropylene chain, polymer chains comprising polyvinyl alcohols such as polyvinyl alcohol and partially saponified polyvinyl alcohol, (Meth) acrylic acid esters such as ethyl acrylate, polyhydroxyethyl methacrylate, dimethylaminoethyl acrylate, and dimethylaminoethyl methacrylate, polyacetylethyleneimine, polyacetylpropyleneimine, A polyacylalkyleneimine chain having a hydrophilic substituent group such as polypropionylethyleneimine and polypropionylpropyleneimine, a polymer chain comprising polyacrylamides such as polyacrylamide, polyisopropylacrylamide and polyvinylpyrrolidone, etc. Among them, a colloid having particularly excellent stability It is preferable that the polyoxyalkylene chain is a polyoxyalkylene chain in view of obtaining a solution and facilitating industrial availability.

In the present invention, the hydrophobic segment (C) may be further contained in the protective polymer. Particularly when the medium is an organic solvent as a metal colloid solution, it is preferable to use a polymer having a hydrophobic segment (C) as a protective agent.

The hydrophobic segment (C) is not particularly limited and can be used as long as it is a commercially available or synthetic hydrophobic compound residue. Examples thereof include polystyrenes such as polystyrene, polymethylstyrene, polychloromethylstyrene and polymethylmethyle styrene, polyacrylic acid methyl ester, polymethacrylic acid methyl ester, polyacrylic acid 2-ethylhexyl ester, polymethacrylic acid 2 (Meth) acryloylethyleneimine, poly (meth) acryloylpropyleneimine, poly [N (meth) acryloyloxypropyleneimine, poly A polymer of a polyacylalkyleneimine having a hydrophobic substituent such as - {3- (perfluorooctyl) propionyl} ethyleneimine] and poly [N- {3- (perfluorooctyl) propionyl} propyleneimine] And residues of resins such as epoxy resins, polyurethanes, and polycarbonates, and the like, and even a residue of a single compound can be obtained by reacting two or more different compounds in advance Or a residue of a compound. Among them, from the viewpoints of easy industrial synthesis of the protective polymer and from the viewpoint of excellent adhesiveness to the base material when printing or applying the obtained metal colloid solution, those having a structure derived from an epoxy resin, in particular, bisphenol A Is preferably a hydrophobic segment (C) composed of a structure derived from an epoxy resin.

The polymerization degree of the hydrophobic segment (C) is not particularly limited, but is usually from 1 to 10,000. In the case of polystyrenes, poly (meth) acrylates, polyacylalkyleneimines having a hydrophobic substituent, etc., , More preferably from 10 to 1,000. When the resin is composed of residues of an epoxy resin, a polyurethane, a polycarbonate or the like, the degree of polymerization is usually 1 to 50, preferably 1 to 30, particularly preferably 1 to 20.

The method for producing a metal nanoparticle protective polymer according to the present invention is a method for producing a metal nanoparticle protective polymer by using a compound having a polyalkyleneimine segment and a hydrophilic segment (B) as the precursor compound (I) or a compound having a polyalkyleneimine segment and a hydrophilic segment (B) and a hydrophobic segment (C), and reacting it with an acetylating agent. Alternatively, there is a method of using an acetylating agent at the time of producing a precursor compound (I) using a polyalkyleneimine segment and a hydrophilic segment (B). By using such a method, a protective polymer as designed can be easily obtained. As to the method for producing the precursor compound (I), the methods described in the above-mentioned Patent Documents 4 and 2006-213887 can be used as they are.

After obtaining such a precursor compound (I), the nitrogen atom in the primary amine and / or the secondary amine in the polyalkyleneimine segment contained therein is acetylated. Alternatively, the nitrogen atom in the primary amine and / or the secondary amine in the polyalkyleneimine segment is acetylated during the production of the precursor compound (I) using the polyalkyleneimine segment and the hydrophilic segment (B). The acetylation reaction is effected by the addition of acetyl agent having the structure acetyl (CH ₃ -CO-).

As the acetylating agent, any one usually supplied industrially can be used. For example, acetic anhydride, acetic acid, dimethylacetamide, ethyl acetate, acetic acid chloride and the like. Among these acetylating agents, acetic anhydride, acetic acid and dimethylacetamide are particularly preferable from the viewpoint of easy access and handling.

When the polyalkyleneimine segment is based on a branched polyalkyleneimine compound, the first-, second-, and third-class amines are uniformly and randomly contained. When an acetylating agent is reacted, one acetyl group oxygen may be added to one nitrogen atom of the primary amine and / or secondary amine. And, it does not react with tertiary amine. That is, the acetylation reaction proceeds from the acetylating agent used to the quantitatively reactive higher primary amine to the secondary amine. Considering the acetylation rate of the primary amine and / or the secondary amine, the acetylation rate in the acetylation reaction was examined. As a result, it was found that 5 to 100 mol% of the primary amine in the polyalkyleneimine segment and 0 To 50 mol%, a protective polymer showing good conductivity, dispersion stability and easy purification separation can be obtained.

As described above, the acetylalkyleneimine unit is decoupled from the surface of the metal nanoparticles easily at a low temperature due to the weaker coordination bonding force with the metal than the alkyleneimine unit, and as a result, good low-temperature plasticity On the other hand, as a metal nanoparticle protective polymer, the dispersion stability in which metal nanoparticles are stably present is weaker than that of the alkyleneimine unit, and further leads to deterioration of dispersion stability by a stronger combination force, That is, the dispersion stability and the low temperature baking performance are trade-off. The range of the above acetylation is specified from the viewpoint of the storage stability of the obtained metal colloid solution and the low temperature sinterability of the coating film obtained using the same.

The metal nanoparticle protective polymer of the present invention has a hydrophilic segment (B) or a hydrophobic segment (C) separately from the polyacetylalkyleneimine segment (A) capable of stably presenting the metal nanoparticles. As described above, the hydrophilic segment (B) exhibits a strong cohesive force in a hydrophobic solvent, exhibits a high affinity with a solvent in a hydrophilic solvent, and the hydrophobic segment (C) exhibits a strong cohesive force in a hydrophilic solvent, And exhibits high affinity with a solvent in a hydrophobic solvent. In addition, in the case of having an aromatic ring in the hydrophobic segment (C), it is considered that? Electrons possessed by the aromatic ring interact with the metal, thereby contributing to stabilization of the metal nanoparticles.

The molar ratio (A) :( B) of the polymer constituting the chain of the respective components of the polyacetyl alkyleneimine segment (A) and the hydrophilic segment (B) in the metal nanoparticle protective polymer of the present invention is not particularly limited, (1 to 100), particularly preferably 1: (1 to 30), from the viewpoint of excellent dispersion stability and storage stability of the metal colloid solution. In the case of a polymer having also a hydrophobic segment (C), the molar ratio (A) :( (A) of the polymer constituting the chain of each component of the polyacetyl alkyleneimine segment (A), the hydrophilic segment (B) and the hydrophobic segment B) :( C) is not particularly limited, but is usually in the range of 1: (1 to 100) :( 1 to 100), particularly 1 :( 1 to 100) in view of excellent dispersion stability and storage stability of the obtained metal colloid solution. 1 to 30) :( 1 to 30). In view of the above, the weight average molecular weight of the metal nanoparticle protective polymer of the present invention is preferably in the range of 1,000 to 500,000, particularly preferably in the range of 1,000 to 100,000.

The protective polymer of the present invention is used in the production of a metal colloid solution by dispersing or dissolving in various media. The material that can be used as the medium is not limited, and the dispersion may be any of an O / W system and a W / O system. A hydrophilic solvent, a hydrophobic solvent, a mixed solvent thereof, or a mixed solvent in which other solvents as described below are used in combination may be selected in accordance with the method for producing the metal colloid solution and the purpose of using the metal colloid solution obtained. When a mixed solvent is used, a hydrophilic solvent is used in the O / W system and a hydrophobic solvent is used in the W / O system. As a general standard, for example, a hydrophilic solvent of 5 times or more the capacity of a hydrophobic solvent is used for an O / W system and a hydrophilic solvent for a hydrophilic solvent is used for a W / O system, although the mixing ratio varies depending on the kind used. It is preferable to use a hydrophobic solvent having a capacity of 5 times or more the capacity of the solvent.

Examples of the hydrophilic solvent include aliphatic hydrocarbons such as methanol, ethanol, isopropyl alcohol, tetrahydrofuran, acetone, dimethylacetamide, dimethylformamide, ethylene glycol, propylene glycol, ethylene glycol monomethyl ether, propylene glycol monomethyl ether, Dimethyl ether, propylene glycol dimethyl ether, dimethyl sulfone oxide, dioxirane, N-methylpyrrolidone and the like, and they may be used singly or in combination of two or more kinds.

Examples of the hydrophobic solvent include hexane, cyclohexane, ethyl acetate, butanol, methylene chloride, chloroform, chlorobenzene, nitrobenzene, methoxybenzene, toluene and xylene. May be used.

Examples of the other solvent that can be used in combination with a hydrophilic solvent or a hydrophobic solvent include ethyl acetate, propyl acetate, butyl acetate, isobutyl acetate, ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether acetate and the like. .

The method of dispersing the metal nanoparticle protective polymer in the medium is not particularly limited and is usually easily attained by standing at room temperature or by stirring, but ultrasonic treatment, heat treatment and the like may be carried out if necessary . When the affinity with the medium is low due to the crystallinity of the protective polymer or the like, for example, after the protective polymer is dissolved or swollen with a small amount of a good solvent (good solvent) Or may be dispersed. In this case, ultrasonic treatment or heat treatment is more effective.

When a hydrophilic solvent and a hydrophobic solvent are mixed and used, there is no particular limitation on the mixing method, mixing order, and the like, and they may be carried out by various methods. There may be a difference in affinity and dispersibility with respect to various solvents depending on the kind and composition of the protective polymer to be used. Therefore, the mixing ratio of the solvent, the mixing order, the mixing method, and the mixing conditions are appropriately selected .

The method for producing a metal colloid solution according to the present invention is a method for reducing metal ions in a solution or dispersion of the above-mentioned protective polymer to form metal nanoparticles. Examples of the metal ion source include metal salts or metal ion solutions have. As the source of the metal ion, a water-soluble metal compound, a salt of a metal cation and an acid anion, or a metal contained in an anion of an acid group can be used, and a metal ion having a metal species such as a transition metal Can be preferably used.

As the transition metal ion, it may be a transition metal cation (M ^{n +} ) or an anion (ML _x ⁿ ^- ) composed of a halogen-based bond, and may be chemically coordinated in a complex state. In the present specification, the transition metal means transition metal elements in Groups 4 to 12 to Groups 4 to 6 of the periodic table.

Examples of the transition metal cation include monovalent, divalent, trivalent or tetravalent cations such as the following transition metal cations (M ^{n +} ), for example, Cr, Co, Ni, Cu, Pd, Ag, . The counter anion of these metal cations may be Cl, NO ₃ , SO ₄ , or an organic anion of a carboxylic acid type.

Further, anions coordinated with a metal halide such as AgNO ₃ , AuCl ₄ , PtCl ₄ and CuF ₆ , which are anions (ML _x ⁿ ^- ) containing the following metals, can also be chemically coordinated in a complex state have.

Of these metal ions, metal ions such as silver, gold and platinum are preferable because they are spontaneously reduced at room temperature or in a heated state and converted into nonionic metal nano-particles. In addition, when the obtained metal colloid solution is used as a conductive material, it is preferable to use silver ions from the viewpoint of the ability to develop conductivity and the antioxidant property of the coating obtained by printing and coating.

It is also possible to use two or more metal species to be contained. In this case, by adding salts or ions of various metals simultaneously or separately, a plurality of metal ions are reduced in the medium to generate a plurality of metal particles, so that a colloid solution containing a plurality of metals Can be obtained.

In the present invention, metal ions may also be reduced by a reducing agent.

As the reducing agent, various reducing agents can be used and are not particularly limited, and it is preferable to select a reducing agent depending on the intended use of the metal colloid solution obtained, the metal species to be contained, and the like. Examples of the reducing agent that can be used include boron compounds such as hydrogen, sodium borohydride and ammonium borohydride, alcohols such as methanol, ethanol, propanol, isopropyl alcohol, ethylene glycol and propylene glycol, formaldehyde, acetaldehyde, Propylamine, butylamine, diethylamine, dipropylamine, dimethylethylamine, triethylamine, ethylenediamine, triethylenetetramine, methylamino, triethylenetetramine, and the like; aldehydes such as propionaldehyde and propionaldehyde; acids such as ascorbic acid, citric acid, and sodium citrate; Amines such as ethanol, dimethylaminoethanol and triethanolamine, hydrazines such as hydrazine and hydrazine carbonate, and the like. Of these, sodium borohydride, ascorbic acid, sodium citrate, methylaminoethanol, dimethylaminoethanol, and the like are more preferable for ease of industrial availability and handling.

In the method for producing the metal colloid solution of the present invention, the ratio of the protective polymer to the source of the metal ion is not particularly limited, but the total nitrogen atoms forming the polyacetylalkyleneimine segment in the protective polymer When the water content is 100 mol, the metal is usually in the range of 1 to 20,000 mol, preferably 1 to 10,000 mol, particularly preferably 50 to 7,000 mol.

In the method for producing a metal colloid solution of the present invention, a method of mixing a metal salt or an ionic solution with a medium in which the protective polymer is dispersed or dissolved is not particularly limited, and the protective polymer is dispersed or dissolved A method of adding a salt of a metal or an ionic solution to the medium, a method of the opposite method, or a method of mixing them simultaneously in a separate vessel. The mixing method such as stirring is not particularly limited.

The method of adding the reducing agent is not limited. For example, the reducing agent may be dissolved or dispersed in an aqueous solution or other solvent. There is no limitation on the order of addition of a reducing agent, and a reducing agent may be added at the same time when a metal salt or an ionic solution is mixed with a reducing agent in advance in the solution or dispersion of the protective polymer. In addition, Or a method of mixing a dispersion with a metal salt or an ionic solution, and then, after a lapse of several days or several weeks, the reducing agent is mixed.

When a salt of a metal or an ionic solution thereof used in the production method of the present invention is added to a medium in which the protective polymer is dispersed or dissolved, it can be added as it is or in an aqueous solution . Since metal ions such as silver, gold, palladium and platinum are spontaneously reduced at room temperature or in a heated state after being coordinated with an acetylalkyleneimine unit in the polymer, they are allowed to stand at room temperature or warmed, And a metal colloid solution which is a dispersion of the complex in which this is protected with a protective polymer can be obtained. However, in order to efficiently perform reduction of metal ions as described above, it is preferable to use a reducing agent. Or by stirring, a metal colloid solution is obtained. At this time, it is preferable to prepare the reducing agent as it is or an aqueous solution. The temperature in the case of heating is generally 100 占 폚 or lower, preferably 80 占 폚 or lower, although it depends on the kind of the protective polymer, the metal used, the type of the medium and the reducing agent.

As described above, by reducing metal ions, metal nanoparticles are precipitated, and the surface of the particles is protected by the protective polymer to stabilize. The solution after the reduction reaction contains an impurity such as a reducing agent, a counter ion of a metal ion, and a protective polymer not involved in the protection of the metal nanoparticles, and as such can not exhibit sufficient performance as a conductive material. However, since the protective polymer of the present invention has a high protecting ability, a poor solvent is added to the reaction solution to protect the complex in which the metal nanoparticles are protected with the protective polymer, It is possible to precipitate well. The precipitated complex may be concentrated or isolated using a process such as centrifugation. After the concentration, the nonvolatile content (concentration) is adjusted to a desired medium according to the use of the metal colloid solution or the like, and is applied to various applications.

The content of the metal nanoparticles in the metal colloid solution obtained in the present invention is not particularly limited. However, if the content is too small, the characteristics of the metal nanoparticles as a colloid solution hardly appear, and if too large, And that the stability of the colloidal solution is expected to be insufficient due to a balance between the relative weight and the dispersing power of the protective polymer and that the acetylalkyleneimine unit in the protective polymer is effective in terms of reducing ability and coordination ability , The content of nonvolatile matter in the metal colloid solution is preferably in the range of 10 to 80 mass%, particularly preferably in the range of 20 to 70 mass%. The content of the metal nanoparticles in the nonvolatile matter is preferably 93% by mass or more, more preferably 95% by mass or more, from the viewpoints of conductivity and the like when the colloidal solution is used as a conductive material.

The particle diameter of the metal nanoparticles contained in the non-volatile component in the metal colloid solution obtained in the present invention is not particularly limited. However, in order for the metal colloid solution to have higher dispersion stability, the metal nanoparticles have a particle diameter of 1 to 70 nm , And more preferably in the range of 5 to 50 nm.

In general, metal nanoparticles in the size range of several tens nm have characteristic optical absorption due to surface plasmon excitation depending on the metal species. Therefore, by measuring the plasmon absorption of the metal colloid solution obtained in the present invention, it can be confirmed that the metal exists as fine particles on the order of nanometers. In addition, Microscope) photograph or the like, it is possible to observe the average particle diameter and the distribution width.

The metal colloid solution obtained in the present invention is not limited in its use because it is dispersed stably for a long period of time in all the media. For example, the metal colloid solution may be a catalyst, electronic material, magnetic material, optical material, various sensors, And can be used in a very wide range of applications. The metal species that can be contained and the ratio thereof can be easily adjusted, and the effect according to the purpose can be efficiently expressed. In addition, it is also possible to cope with long-term use and long-term preservation because it is dispersed stably over a long period of time, which is highly useful. Further, since the method of producing the metal colloid solution of the present invention requires little complicated process or fine condition setting, it has a high advantage as an industrial production method.

[Example]

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. Unless otherwise indicated, "%" represents "% by mass".

Among the following examples, the used instruments and measuring methods are as follows.

¹ H-NMR: AL300, manufactured by Nippon Denshige Co., 300 Hz

Measurement of particle size: FPAR-1000 manufactured by Otsuka Chemical Co., Ltd.

Plasmon absorption spectrum: UV-3500 manufactured by Hitachi Seisakusho Co., Ltd.

Identification of the structure of the protective polymer by ¹ H-NMR

About 3 mL of the solution of the protective polymer was concentrated and sufficiently dried under reduced pressure, and the residue was dissolved in about 0.8 mL of a solvent for NMR measurement such as chloroform containing 0.03% tetramethylsilane, and the residue was analyzed by glass NMR And a ¹ H-NMR spectrum was obtained by a JEOL JNM-LA300 type nuclear magnetic resonance absorption spectrometer. The chemical shift value delta indicates tetramethylsilane as a reference material.

Measurement of particle size by dynamic light scattering method

A part of the metal colloidal solution was diluted with purified water and the particle size distribution and average particle size were measured by a FPAR-1000 type concentrated-system particle size analyzer (manufactured by Otsuka Chemical Co., Ltd.).

Determination of metal content in non-volatile matter by thermogravimetric analysis

About 1 mL of the metal colloid solution was taken in a glass sample bottle, and the mixture was concentrated by heating on a boiling water bath under a nitrogen stream, and the residue was further vacuum dried at 50 DEG C for 8 hours or longer to obtain a nonvolatile matter. 2 to 10 mg of this nonvolatile matter was precisely weighed in an aluminum pan for thermogravimetric analysis and placed on an EXSTAR TG / DTA6300 differential thermal analyzer (manufactured by Seiko Instruments Inc.), and the temperature was raised from room temperature to 500 ° C The temperature was raised at a rate of 10 ° C per minute, and the weight loss rate accompanying the heating was measured. The content of silver in the non-volatile matter was calculated by the following formula.

Metal content (%) = 100-Weight reduction ratio (%)

Resistivity measurement of metal thin film obtained from metal colloid solution

About 0.5 mL of the metal colloid solution was dropped on the top of a clean glass plate of 2.5 × 5 cm, and the coating film was formed using the bar coater No. 8. The resulting coated film was air-dried and then heated in a hot-air dryer at 125 ° C and 180 ° C for 30 minutes to obtain a fired film. The thickness of the obtained fired coating film was measured using an Optelix C130 type real color confocal microscope (manufactured by Laser Tec), and then the surface resistivity (Ω / □) was measured with a Loresta-EP MCP-T360 type low resistivity meter (Manufactured by Kagaku Co., Ltd.) according to JIS K7194 " Resistivity Test by 4-probe Method of Conductive Plastics ". The coating film thickness was a constant value of approximately 0.3 탆 according to the above conditions, and the volume resistivity (? Cm) was calculated from the thickness and the surface resistivity (? /?) Using the following equation.

Volume resistivity (? Cm) = surface resistivity (? /?) X thickness (cm)

[Synthesis Example 1] Synthesis of tosylated polyethylene glycol monomethyl ether

(50.0 mmol) of p-toluenesulfonic acid chloride was added to a mixed solution of 20.0 g (10.0 mmol) of methoxypolyethylene glycol [Mn = 2,000], 8.0 g (100.0 mmol) of pyridine and 20 ml of chloroform in a nitrogen atmosphere. A solution of chloroform (30 ml) was added dropwise over 30 minutes while stirring with ice. After completion of the dropwise addition, the mixture was further stirred at a bath temperature of 40 DEG C for 4 hours. After completion of the reaction, 50 ml of chloroform was added to dilute the reaction solution. Subsequently, the solution was washed successively with 100 ml of a 5% aqueous hydrochloric acid solution, 100 ml of a saturated aqueous sodium hydrogencarbonate solution and 100 ml of a saturated saline solution, successively, dried over magnesium sulfate, filtered and concentrated under reduced pressure. The resulting solid was washed several times with hexane, filtered, and dried under reduced pressure at 80 캜 to obtain 22.0 g of a tosylated product.

The measurement results of ¹ H-NMR (AL300, 300 MHz, manufactured by Nippon Denshoku Co., Ltd.) of the obtained product are shown below.

¹ H-NMR (CDCl ₃₎ measurement results:

4.2 (t, 2H, J = 4.2 Hz, sulfonic acid ester adjacent position (ppm) = 7.8 (d, 2H, J = 7.8 Hz, ), 3.6-3.5 (m, PEGM methylene), 3.4 (s, 3H, PEGM chain terminal methoxy group), 2.4 (s, 3H, tosylmethyl).

[Synthesis Example 2] Synthesis of polyethyleneimine-b-polyethylene glycol copolymer

19.3 g (9.0 mmol) of the tosylated polyethylene glycol obtained in the above Synthesis Example 1 and 30.0 g (3.0 mmol) of polyethyleneimine (EPOMIN SP200, manufactured by Nippon Shokubai K.K.) were dispersed in a nitrogen atmosphere at 60 占 폚 After mixing and stirring, 0.18 g of potassium carbonate was added and the mixture was stirred at a reaction temperature of 120 DEG C for 6 hours. After completion of the reaction, the reaction solution was diluted with a THF solvent, and then the residue was removed, followed by concentration under reduced pressure at 30 ° C. The resulting solid was redissolved in THF solvent, and then heptane was added thereto to further refill the residue. This was separated by filtration and concentrated under reduced pressure to obtain 48.1 g (yield: 99%) of a pale yellow solid.

The results of ¹ H-NMR, ¹³ C-NMR (AL 300, 300 MHz, manufactured by Nippon Denshoku Chemical Co., Ltd.) and elemental analysis of the obtained product are shown below.

¹ H-NMR (CDCl ₃₎ measurement results:

? (ppm) = 3.57 (br s, PEGM methylene), 3.25 (s, 3H, PEGM chain end methoxy group), 2.65-2.40 (m, branched PEI ethylene).

¹³ C-NMR (DMSO-d ₆ ) measurement result:

(ppm) = 39.9 (s), 41.8 (s), 47.6 (m), 49.5 (m), 52.6 (m), 54.7 , 70.5 (m), 71.8 (s) (more than PEGM methylene and terminal methoxy groups).

The results of elemental analysis showed that C (53.1%), H (10.4%), N (19.1%),

[Synthesis Example 3] Synthesis of polyethyleneimine-b-polyethylene glycol-b-bisphenol A type epoxy resin

37.4 g (20 mmol) of EPICLON AM-040-P (bisphenol A type epoxy resin, epoxy equivalent 933, manufactured by DIC Corporation) and 2.72 g (16 mmol) of 4-phenylphenol were dissolved in 100 mL of N, N- dimethylacetamide Then, 0.52 mL of an ethanol solution of 65% acetic acid ethyltriphenylphosphonium was added, and the mixture was reacted at 120 DEG C for 6 hours in a nitrogen atmosphere. After cooling, the mixture was dropped into a large amount of water, and the resulting precipitate was washed with a large amount of water. The residue was dried under reduced pressure to obtain a modified bisphenol A type epoxy resin. The yield of the obtained product was 98%. ¹ H-NMR measurement was carried out to examine the integral ratio of epoxy groups. As a result, it was confirmed that 0.95 epoxy rings remained in one molecule of bisphenol A type epoxy resin, and that the product was a monofunctional epoxy resin having a bisphenol A skeleton.

The measurement results of ¹ H-NMR (AL300, 300 MHz, manufactured by Nippon Denshoku Co., Ltd.) of the resulting monofunctional epoxy resin are shown below.

¹ H-NMR (CDCl ₃₎ measurement results:

[delta] (ppm): 7.55-6.75 (m), 4.40-3.90 (m), 3.33 (m), 2.89 (m), 2.73 (m), 1.62

Acetone (50 mL) solution of 3.2 g (1.6 mmol) of the above-described modified epoxy resin was added dropwise to a methanol (150 mL) solution of 20 g (0.8 mmol) of the polyethyleneimine-b-polyethylene glycol copolymer obtained in Synthesis Example 2, Followed by stirring at 50 ° C for 2 hours. After completion of the reaction, the solvent was distilled off under reduced pressure, and further, vacuum drying was conducted to obtain a polyethyleneimine-b-polyethylene glycol-b-bisphenol A type epoxy resin. The yield was 100%.

¹ H-NMR (CDCl ₃₎ measurement results:

[delta] (ppm) = 7.55 to 6.75 (m), 4.40 to 3.90 (m), 3.57 (brs), 3.33 (m), 3.25 (s), 2.89 ), 1.62 (s).

[Example 1] Synthesis of protective polymer (1-1)

(9.0 mmol) of the tosylated polyethylene glycol obtained in Synthesis Example 1 and 30.0 g (3.0 mmol) of polyethyleneimine (Nippon Shokubai K.K., Epomin SP200) in a nitrogen atmosphere were added N, N -Dimethylacetamide (270 ml), potassium carbonate (0.18 g) was added, and the mixture was stirred at a reaction temperature of 120 DEG C for 6 hours. After completion of the reaction, the solid matter was removed, and the mixture was concentrated under reduced pressure at 70 ° C. A mixture of 200 ml of ethyl acetate and 600 ml of hexane was added to the residue to obtain a precipitate. The obtained precipitate was separated, diluted with a THF solvent, and then the residue was removed and concentrated under reduced pressure at 30 캜. The resulting solid was redissolved in THF solvent, and then heptane was added thereto to further refill the residue. This was separated by filtration and concentrated under reduced pressure to give 47.8 g (yield: 98%) of a pale yellow solid.

The measurement results of ¹ H-NMR and ¹³ C-NMR (AL 300, 300 MHz, manufactured by Nippon Denshoku Co., Ltd.) of the obtained product are shown below.

¹ H-NMR (CDCl ₃₎ measurement results:

? (ppm) = 3.57 (br s, PEGM methylene), 3.25 (s, 3H, PEGM chain end methoxy group), 3.16 (m, 2H, vicinal methylene group of acetyl N), 2.65-2.40 ), 1.90 (br s, 3H, acetyl group of primary N).

¹³ C-NMR (DMSO-d ₆ ) measurement result:

[delta] (ppm) = 22.9 (s) (acetyl group of the first class N), 39.9 (s), 41.8 (s), 47.6 (m), 49.5 (m), 52.6 (m), 54.7 m) (more branched PEI ethylene), 59.0 (s), 70.5 (m), 71.8 (s) (more than PEGM methylene and terminal methoxy groups), 173.4 (m) (acetyl groups).

^{In the 1} H-NMR measurement, it was considered that 11 mol% of the primary amine in the branched polyethyleneimine was acetylated in the calculation of the integral ratio of the 1.90 ppm peak in which the primary amine of the polyethyleneimine in the branched form was acetylated.

[Example 2] Synthesis of protective polymer (1-2)

(9.0 mmol) of the tosylated polyethylene glycol obtained in Synthesis Example 1 and 30.0 g (3.0 mmol) of polyethyleneimine (Nippon Shokubai K.K., Epomin SP200) in a nitrogen atmosphere were added N, N -Dimethylacetamide (270 ml), potassium carbonate (0.18 g) was added, and the mixture was stirred at a reaction temperature of 140 占 폚 for 6 hours. After completion of the reaction, the solid matter was removed, and the mixture was concentrated under reduced pressure at 70 ° C. A mixture of 200 ml of ethyl acetate and 600 ml of hexane was added to the residue to obtain a precipitate. The obtained precipitate was separated, diluted with a THF solvent, and then the residue was removed and concentrated under reduced pressure at 30 캜. The resulting solid was redissolved in THF solvent, and then heptane was added thereto to further refill the residue. This was separated by filtration and concentrated under reduced pressure to give 48.0 g (yield: 98%) of a pale yellow solid.

¹ H-NMR (CDCl ₃₎ measurement results:

¹³ C-NMR (DMSO-d ₆ ) measurement result:

^{In the 1} H-NMR measurement, it was considered that 30 mol% of the branched PEI ethylene primary amine was acetylated in the calculation of the integral ratio of 1.90 ppm peak in which the primary amine of the branched polyethyleneimine was acetylated.

[Example 3] Synthesis of protective polymer (1-3)

9.98 g (N equivalent, 145 mmol) of the protective polymer (1-2) (30 mol% acetylated product of the primary amine of the polyethyleneimine-b-polyethylene glycol copolymer) obtained in Example 2 was dissolved in 45 g of chloroform, Deg.] C, 1.48 g of acetic anhydride was slowly added to conduct the acetylation reaction for 2 hours. After the reaction, the resulting residue was filtered through a strong alkali treatment, and then concentrated under reduced pressure to obtain 10.5 g of a pale yellow solid (yield: 99%).

¹ H-NMR (CDCl ₃₎ measurement results:

? (ppm) = 3.57 (br s, PEGM methylene), 3.25 (s, 3H, PEGM chain end methoxy group), 3.16 (m, 2H, vicinal methylene group of acetyl N), 2.65-2.40 ), 2.11 (br s, 3H, acetyl group of the second class N), 1.90 (br s, 3H, acetyl group of the first class N).

¹³ C-NMR (DMSO-d ₆ ) measurement result:

δ (ppm) = 21.4 (s) (acetyl group of the second class N), 22.9 (s) (acetyl group of the first class N), 39.9 (s), 41.8 (s), 47.6 (m) , 59.6 (m), 54.7 (m), 57.8 (m) (branched PEI ethylene), 59.0 (s), 70.5 (m), 71.8 (Acetyl group).

^{In the 1} H-NMR measurement, 58 mol% of the primary amine of the branched polyethyleneimine and 58 mol% of the secondary amine of the branched polyethyleneimine in the calculation of the integral ratios of the 1.90 ppm and 2.11 ppm peaks in which the primary and secondary amine of the branched polyethyleneimine were acetylated, It is believed that 11 mol% of the compound was acetylated.

[Example 4] Synthesis of protective polymer (1-4)

9.98 g (N equivalent, 145 mmol) of the protective polymer (1-2) (30 mol% acetylated product of the primary amine of the polyethyleneimine-b-polyethylene glycol copolymer) obtained in Example 2 was dissolved in 45 g of chloroform, Deg.] C, 2.96 g of acetic anhydride was slowly added to conduct the acetylation reaction for 2 hours. After the reaction, the resulting residue was filtered through a strong alkali treatment, and then concentrated under reduced pressure to obtain 11.0 g of a pale yellow solid (yield: 98%).

¹ H-NMR (CDCl ₃₎ measurement results:

¹³ C-NMR (DMSO-d ₆ ) measurement result:

^{In the 1} H-NMR measurement, in the calculation of the integral ratios of 1.90 ppm and 2.11 ppm peaks in which the primary and secondary amine of the branched polyethyleneimine were acetylated, 88 mol% of the primary amine of the branched polyethyleneimine and the secondary amine It is believed that 22 mol% of the compound was acetylated.

[Example 5] Synthesis of protective polymer (1-5)

9.98 g (N equivalent, 145 mmol) of the protective polymer (1-2) (30 mol% acetylated product of the primary amine of the polyethyleneimine-b-polyethylene glycol copolymer) obtained in Example 2 was dissolved in 45 g of chloroform, Deg.] C, 4.44 g of acetic anhydride was slowly added to conduct the acetylation reaction for 2 hours. After the reaction, the resulting residue was filtered through a strong alkali treatment, and then concentrated under reduced pressure to obtain 13.7 g of a pale yellow solid (yield: 95%).

¹ H-NMR (CDCl ₃₎ measurement results:

¹³ C-NMR (DMSO-d ₆ ) measurement result:

^{In the 1} H-NMR measurement, 96 mol% of the primary amine of the branched polyethyleneimine and 96 mol% of the secondary amine of the branched polyethyleneimine in the calculation of the integral ratios of the 1.90 ppm and 2.11 ppm peaks in which the primary and secondary amine of the branched polyethyleneimine were acetylated, It is considered that 54 mol%

[Comparative Example 1] Synthesis of Protecting Polymer (1 ')

9.98 g (N equivalent, 145 mmol) of the protective polymer (1-2) (30 mol% acetylated product of the primary amine of the polyethyleneimine-b-polyethylene glycol copolymer) obtained in Example 2 was dissolved in 45 g of chloroform, Deg.] C, 7.40 g of acetic anhydride was slowly added to conduct the acetylation reaction for 2 hours. After the reaction, the resulting residue was filtered through a strong alkali treatment, and then concentrated under reduced pressure to obtain 12.0 g of a pale yellow solid (yield: 92%).

¹ H-NMR (CDCl ₃₎ measurement results:

¹³ C-NMR (DMSO-d ₆ ) measurement result:

^{In the 1} H-NMR measurement, 96 mol% of the primary amine of the branched polyethyleneimine and 96 mol% of the secondary amine of the branched polyethyleneimine in the calculation of the integral ratios of the 1.90 ppm and 2.11 ppm peaks in which the primary and secondary amine of the branched polyethyleneimine were acetylated, It is believed that 98 mol% of the product was acetylated.

[Example 6] Synthesis of protective polymer (2-1)

The bisphenol A skeleton synthesized in Synthesis Example 3 was added to a methanol (150 mL) solution of 20 g (1.25 mmol) of the acetylation product of the polyethyleneimine-b-polyethylene glycol copolymer as the protective polymer (1-3) obtained in Example 3 In an acetone (50 mL) solution of 3.2 g (1.6 mmol) of a modified epoxy resin as a monofunctional epoxy resin was added dropwise under a nitrogen atmosphere, followed by stirring at 50 DEG C for 2 hours. After completion of the reaction, the solvent was distilled off under reduced pressure, and the residue was further dried under reduced pressure to obtain a polyacetylethyleneimine-b-polyethylene glycol-b-bisphenol A type epoxy resin. The yield was 100%.

¹ H-NMR (CDCl ₃₎ measurement results:

(ppm) = 7.55 to 6.75 m, 4.40 to 3.90 m, 3.57 (br s, PEGM methylene), 3.33 (m), 3.25 (s, 3H, PEGM chain end methoxy group), 3.16 2H, the adjacent methylene group of acetyl N), 2.89 (m), 2.73 (m), 2.65-2.40 (m, branched PEI ethylene), 2.11 (br s, 3H, , 3H, acetyl group of primary N), 1.62 (s).

^{In the 1} H-NMR measurement, in the calculation of the integral ratios of the 1.90 ppm and 2.11 ppm peaks in which the primary and secondary amine of the branched polyethyleneimine were acetylated, 56 mol% of the primary amine of the branched polyethyleneimine and the secondary amine &Lt; / RTI > is believed to be acetylated.

[Example 7] Synthesis of silver colloid solution with protective polymer (1-1) of Example 1

180 g of pure water, 13.5 g of the aqueous solution of the protective polymer (1-1) obtained in Example 1 and 113 g (1.27 mol) of N, N-dimethylaminoethanol were added in this order to a 1 L reaction kettle and stirred to obtain a protective polymer and a reducing agent Was prepared. Separately, 72.0 g (0.424 mol) of silver nitrate was dissolved in 120 g of pure water, and the adjusted silver nitrate aqueous solution was added dropwise at 40 DEG C over about 30 minutes, and then stirred at 50 DEG C for 5 hours. After completion of the reaction and cooling, 1.9 L of acetone in the poor solvent (about 4 vol. Of the reaction mixture) was added, and the mixture was stirred for 5 minutes. The composite of the silver nanoparticles and the protective polymer was separated by settling for about 1 hour. After removal of the supernatant, the resulting precipitate was centrifuged. The paste-like precipitate, which was centrifuged, was washed with pure water, further centrifuged, and 80 g of pure water was added to the precipitate of the paste phase to be well dispersed. The residual acetone was removed by a solvent, The mixture was concentrated under reduced pressure until about 60% of the unreacted volatile matter was obtained. Thus, 77.0 g of an aqueous silver colloid solution was obtained (46.5 g as a nonvolatile matter, 97% yield). As a result of thermal analysis (Tg / DTA), the content of silver in the nonvolatile material was 95.8%.

[Example 8] Synthesis of silver colloid solution with protective polymer (1-2) of Example 2

The procedure of Example 7 was repeated except that 14.2 g of the aqueous solution of the protective polymer (1-2) obtained in Example 2 was used instead of 13.5 g of the aqueous solution of the protective polymer (1-1) obtained in Example 1, 73.0 g of a silver colloid aqueous solution of about 60% was obtained (45.1 g as a nonvolatile material, 94% yield). As a result of thermal analysis (Tg / DTA), the content of silver in the nonvolatile material was 96.0%.

[Example 9] Synthesis of silver colloid solution with protective polymer (1-3) of Example 3

Except that 15.5 g of the aqueous solution of the protective polymer (1-3) obtained in Example 3 was used instead of 13.5 g of the aqueous solution of the protective polymer (1-1) obtained in Example 1, 74.0 g of a silver colloid aqueous solution of about 60% was obtained (46.2 g as a nonvolatile material, 96% yield). As a result of thermal analysis (Tg / DTA), the content of silver in the nonvolatile material was 96.0%.

[Example 10] Synthesis of silver colloid solution with protective polymer (1-4) of Example 4

Except that 17.0 g of the aqueous solution of the protective polymer (1-4) obtained in Example 4 was used instead of 13.5 g of the aqueous solution of the protective polymer (1-1) obtained in Example 1, 75.0 g of a silver colloid aqueous solution of about 60% was obtained (45.6 g as a nonvolatile material, a yield of 95%). As a result of thermal analysis (Tg / DTA), the content of silver in the nonvolatile material was 96.1%.

[Example 11] Synthesis of silver colloid solution with protective polymer (1-5) of Example 5

The procedure of Example 7 was repeated except that 17.5 g of the aqueous solution of the protective polymer (1-5) obtained in Example 5 was used instead of 13.5 g of the aqueous solution of the protective polymer (1-1) obtained in Example 1, 70.0 g of a silver colloid aqueous solution of about 60% was obtained (45.0 g as a nonvolatile material, 94% yield). As a result of thermal analysis (Tg / DTA), the content of silver in the nonvolatile material was 96.4%.

[Comparative Example 2] Synthesis of silver colloid solution with protective polymer (1 ') of Comparative Example 1

The procedure of Example 7 was repeated except that 19.9 g of the aqueous solution of the protective polymer (1 ') obtained in Comparative Example 1 was used instead of 13.5 g of the aqueous solution of the protective polymer (1-1) obtained in Example 1, 70.0 g of a 60% silver colloid aqueous solution was obtained (43.6 g as a nonvolatile matter, 91% yield). As a result of thermal analysis (Tg / DTA), the content of silver in the nonvolatile material was 95.5%.

[Example 12] Synthesis of silver colloid solution with protective polymer (2-1) of Example 6

The procedure of Example 7 was repeated except that 16.9 g of the aqueous solution of the protective polymer (2-1) obtained in Example 6 was used instead of 13.5 g of the aqueous solution of the protective polymer (1-1) obtained in Example 1, 76.0 g of a silver colloid aqueous solution of about 60% was obtained (45.8 g as a nonvolatile matter, 95% yield). As a result of thermal analysis (Tg / DTA), the content of silver in the nonvolatile material was 95.6%.

[Comparative Example 3] Synthesis of silver colloid solution with the compound of Synthesis Example 2

A non-volatile matter was obtained in the same manner as in Example 7 except that an aqueous solution prepared by dissolving 9.5 g of pure water in 3.5 g of the compound obtained in Synthesis Example 2, instead of 13.5 g of the aqueous solution of the protective polymer (1-1) obtained in Example 1 74.0 g of a silver colloid aqueous solution of about 60% was obtained (45.7 g as a nonvolatile matter, 95% yield). As a result of thermal analysis (Tg / DTA), the content of silver in the nonvolatile material was 96.0%.

[Comparative Example 4] Synthesis of silver colloid solution with the compound of Synthesis Example 3

A nonvolatile matter was obtained in the same manner as in Example 7 except that an aqueous solution prepared by dissolving 9.5 g of pure water in 4.1 g of the compound obtained in the above Synthesis Example 3 instead of 13.5 g of the aqueous solution of the protective polymer (1-1) obtained in Example 1 77.0 g of a silver colloid aqueous solution of about 60% was obtained (45.5 g as a nonvolatile material, 95% yield). As a result of thermal analysis (Tg / DTA), the content of silver in the nonvolatile material was 95.5%.

Using the silver colloid solutions obtained in Examples 7 to 12 and Comparative Examples 2 to 4, the resistance value and the average particle diameter of the metal thin film were measured in accordance with the above. The amount and time used in the treatment in the sedimentation treatment with acetone in the synthesis are shown in Table 2 below. The stability of the obtained silver colloid solution was evaluated from the appearance when the silver colloid solution was stored at room temperature (25 to 35 ° C) for 1 week. The results are shown in Tables 1 and 2. Note that O.L. in Table 1 indicates an overscale.

As a result, when a protective polymer having an acetylation rate of primary amine in the polyalkyleneimine segment of 5 to 100 mol% and an acetylation rate of secondary amine of 0 to 50 mol% was used, good conductivity, dispersion stability and easy purification separation Is considered to represent the surname.

[Table 1]

[Table 2]

Claims

(A) in which 5 to 100 mol% of a primary amine in a polyalkyleneimine and 0 to 50 mol% of a secondary amine are acetylated in one molecule and a hydrophilic segment (B) having a hydrophilic segment &Lt; / RTI >

The method according to claim 1,
Further comprising a hydrophobic segment (C) in one molecule.

3. The method according to claim 1 or 2,
Wherein the hydrophilic segment (B) comprises a polyoxyalkylene chain.

3. The method of claim 2,
Wherein the hydrophobic segment (C) comprises a residue of an epoxy resin.

3. The method according to claim 1 or 2,
Wherein the number of alkyleneimine units of the polyacetylalkyleneimine segment (A) is in the range of 5 to 2,500.

3. The method according to claim 1 or 2,
A metal nanoparticle protective polymer having a weight average molecular weight in the range of 1,000 to 100,000.

A process for producing a metal nanoparticle protective polymer characterized by acetylating an alkyleneimine unit using an acetylating agent when polymerizing a compound having a polyalkyleneimine segment and a compound having a hydrophilic segment (B).

Wherein a compound having a polyalkyleneimine segment and a hydrophilic segment (B) in one molecule is used as a precursor and the alkyleneimine unit is acetylated using an acetylating agent.

Wherein the metal nanoparticles comprise a polyacetylalkyleneimine segment (A) in which 5 to 100 mol% of a primary amine in a polyalkyleneimine and 0 to 50 mol% of a secondary amine are acetylated, and a hydrophilic segment (B) Wherein the metal nanoparticle protective polymer is dispersed in a medium.

10. The method of claim 9,
Wherein the metal nanoparticles are silver nanoparticles.

11. The method according to claim 9 or 10,
Wherein the metal nanoparticles have a diameter of 5 to 50 nm.

(A) in which 5 to 100 mol% of a primary amine in a polyalkyleneimine and 0 to 50 mol% of a secondary amine are acetylated in one molecule and a hydrophilic segment (B) having a hydrophilic segment Wherein the metal nanoparticles are reduced to metal nanoparticles in the presence of the metal nanoparticle protective polymer.

13. The method of claim 12,
Wherein the metal nanoparticles are silver nanoparticles.