JP5685372B2 - Metal ink, metal-containing film using the same, and method for producing the same - Google Patents

Description

  The present invention relates to a metal ink containing metal particles. Moreover, it is related with the manufacturing method of the metal containing film | membrane using the metal ink. Furthermore, it is related with the decoration film | membrane, electrode, and wiring pattern which are the specific uses of this metal containing film | membrane.

  Metallic ink, in which metal particles are dispersed in a solvent, and further blended with additives such as binders, dispersants, viscosity modifiers, etc., as necessary, uses its metallic properties to ensure electrical continuity, for example. Alternatively, they have been used for various purposes such as antistatic, electromagnetic shielding or metallic luster, antibacterial properties and the like. In recent years, since nano-sized metal particles having an average particle diameter of about 1 to 200 nm have been used as the metal particles to be blended, their uses have expanded to various fields, such as fine electrodes and circuit wiring. A technique for forming a pattern has been proposed. This is a method in which a metal ink containing metal particles is applied onto a substrate in the form of an electrode or circuit wiring pattern by a coating technique such as screen printing or ink jet printing, and then heated to fuse the metal particles. It is being applied to the manufacture of substrates. Furthermore, when the metal particles are nano-order, the size effect of the particles facilitates the fusion of the particles even at a temperature lower than the melting point of the bulk material. Has been.

As such a metal ink, for example, Patent Document 1 discloses a polymer dispersant such as polyvinyl pyrrolidone, polyvinyl alcohol, polyethylene glycol, polyethylene oxide, starch, gelatin on the surface of metal particles having an average primary particle size of nano-size. By using an organic solvent containing a polyol having two or more hydroxyl groups in the main chain as a solvent, a metal particle dispersion solution having excellent dispersibility can be obtained, and polymer dispersion can be performed by heating using the dispersion solution. It describes that a coating film excellent in conductivity can be produced by decomposing the agent.
Patent Document 2 is a metal particle dispersion composed of metal particles having a primary particle size of 30 nm or less and a dispersion medium, and a metal particle dispersion containing a linear aliphatic polyether compound is used as the dispersion medium. In addition, it is described that a low-resistance metal thin film can be produced by decomposing a dispersion medium by heating under normal pressure.

JP 2008-138286 A JP 2006-9120 A

In the metal particle dispersion solution of Patent Document 1, since the polymer dispersant is dispersed in a solution state by coating the surface of the metal particles, it is necessary to use a polymer having a relatively low molecular weight. As a result of being decomposed by heating, there is a problem that the adhesion between the coating film and the substrate is not sufficient, and the coating film strength is fragile. Therefore, surface defects such as cracks and defects such as peeling are likely to occur, leading to a decrease in conductivity and a decrease in commercial value.
The metal fine particle dispersion of Patent Document 2 contains a linear aliphatic polyether compound, particularly one having a molecular weight of 150 to 600, as a dispersion medium, but has the same problems as the invention of Patent Document 1 described above. .
In the method of directly applying the coating material in which the metal particles are dispersed as described above to the substrate, there is a problem that the adhesion of the obtained metal coating film to the substrate is low.
Also, in recent expansion of the use of metal particles, application to various base materials has been studied due to the property that a coating film can be formed at a relatively low temperature. The heat-resistant base material and the metal coating film generally have poor adhesion, and a flexible base material has a problem that defects such as peeling easily occur with deformation.

  As a result of intensive studies to solve the above problems, the present inventors have blended a specific amount of polyether and an adhesion-imparting agent, and the total amount thereof is within a specific range. In addition, the inventors have found that a metal-containing film having a strong adhesiveness and excellent finished appearance such as metallic luster can be obtained, and the present invention has been completed.

That is, the present invention
(1) 0.1-20 parts by weight of metal particles, a solvent, 0.5-20 parts by weight of polyether with respect to 100 parts by weight of the metal particles, and 0.1-20 parts by weight with respect to 100 parts by weight of the metal particles A metal ink containing at least a property-imparting agent, wherein the total amount of the polyether and the adhesion-imparting agent is 0.6 to 20.5 parts by weight with respect to 100 parts by weight of the metal particles,
(2) a metal ink in which the polyether is polyethylene oxide,
(3) a metal ink in which the adhesion-imparting agent is a polymer having a CO double bond in a unit structure;
(4) A metal ink in which the polymer having a CO double bond in the unit structure is polyester,
(5) A metal ink containing an amide solvent,
(6) The constituent component of the metal particles is a metal ink that is at least one selected from copper, silver, gold, nickel, palladium and platinum,
(7) A method for producing a metal-containing film, wherein the metal ink according to any one of (1) to (6) is printed or coated on a substrate.
(8) A method for producing a metal-containing film in which the metal ink according to any one of (1) to (6) is printed or coated on a substrate and then heat-treated at a temperature of 200 ° C. or lower.
(9) A decorative film produced using the metal ink according to any one of (1) to (6),
(10) A decorative film having a coating film with a specular gloss of 400 or more measured under conditions of an incident angle and a reflection angle of 20 degrees in a spectrocolorimeter,
(11) An electrode and a wiring pattern produced using the metal ink according to any one of (1) to (6),
(12) A component having the decorative film, electrode, or wiring pattern according to any one of (9) to (11).

Even if the heat treatment is not performed by adding both the polyether and the adhesion-imparting agent, the metal ink according to the present invention can be added to the base material even if a very small amount is added. Adhesiveness is improved, and a metal film excellent in finished appearance such as smoothness and metallic luster can be obtained. In particular, even when a low heat resistant material such as resin or glass is used as a base material, adhesion is good and defects such as peeling are unlikely to occur. For this reason, it is difficult to produce defective products due to surface defects, dropouts, defects, etc. of the metal film, and it is used reliably for materials that ensure electrical continuity, or materials that provide antistatic, electromagnetic shielding or metallic luster, etc. In particular, it is used for the formation of fine electrodes such as printed wiring boards and circuit wiring patterns utilizing the conductivity of metal films, and for design and decoration applications utilizing the mirror surface of metal films.
Moreover, the metal ink of the present invention can be adjusted to a range of viscosity suitable for various printing methods and coating methods by appropriately adjusting the amount of the polyether as a viscosity-imparting agent. Using a coating machine, printing or coating can be performed on a substrate without causing printing unevenness and coating unevenness.

  The metal ink of the present invention includes a composition generally referred to as a coating agent, paint, paste, ink, dispersion, etc., and includes at least (1) metal particles, (2) a solvent, and (3) the metal described above. 0.5 to 20 parts by weight of polyether with respect to 100 parts by weight of particles, and (4) at least 0.1 to 20 parts by weight of an adhesion-imparting agent with respect to 100 parts by weight of the metal particles, The total amount of (3) and (4) is 0.6 to 20.5 parts by weight with respect to 100 parts by weight of the metal particles.

Next, each component mix | blended with the metal ink of this invention is demonstrated.
(1) Metal particles The metal particles used in the present invention are not particularly limited in their constituent components, and can be appropriately selected according to the application. As the metal component, if it is at least one selected from the group consisting of Group VIII (iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium, platinum) and Group IB (copper, silver, gold) as the metal component, It is preferable because it has high conductivity, and among them, at least one selected from copper, silver, gold, nickel, palladium and platinum is preferable because a mirror-glossy surface can be easily obtained. Silver, gold, platinum, palladium, and copper are particularly preferable because of high conductivity, and silver or copper is particularly preferable for use in forming electrodes and circuit wiring patterns because of the balance between conductivity and cost. Moreover, even if it is 1 type of metal, it may be comprised by 2 or more types of metals by making it an alloy or laminating | stacking. The metal particles may contain impurities such as oxygen and foreign metals that are unavoidable in the manufacturing process, or oxygen, metal oxide, and organic in advance as necessary to prevent rapid oxidation of the metal particles. A compound etc. may be contained.

  Since the particle size of the metal particles is easily available, it is preferable to appropriately use metal particles having an average particle size of about 1 nm to 10 μm, more preferably metal particles having an average particle size of about 1 nm to 1 μm, and various uses. Metal particles having an average particle diameter of about 1 to 100 nm are more preferable, and in order to obtain finer electrodes, circuit wiring patterns and excellent specular gloss surfaces, the average in the range of 1 to 50 nm More preferably, metal particles having a particle size are used. In the present invention, one kind of metal particles may be used, or two or more kinds of metal particles may be mixed and used. For example, two or more kinds of metal particles having different average particle diameters, two or more kinds having different constituent components. These metal particles may be mixed and used. The average particle size of the metal particles is determined by measuring the particle size of each of 1000 particles from an electron micrograph and calculating the number average.

  The metal particles can be produced using a known method. For example, (1) a method in which a metal is evaporated in a vacuum to condense the metal particles from a gas phase, and (2) a reducing agent is added to the metal compound solution. Can be used, and metal particles can be precipitated from the liquid phase. The method (2) is more preferable because the metal particles can be obtained at a low cost. In the method (2), as the metal compound that is a raw material for producing metal particles, for example, the metal chloride, sulfate, nitrate, carbonate, oxide, and the like can be used. An organic solvent such as water or alcohol, or a mixed solvent of two or more of these can be used for the medium for dissolving the metal compound. The concentration of the metal compound in the liquid medium is not particularly limited as long as the metal compound can be dissolved, but is preferably 5 mmol / liter or more industrially. If the metal compound is hardly soluble in water, a compound that forms a soluble complex with the metal component can be added and used.

  As the reducing agent used in the reaction in the liquid phase, known ones can be used. For example, (1) hydrazine or a hydrate thereof, (2) hydrazine compounds (for example, hydrazine hydrochloride, hydrazine sulfate, etc.), ( 3) Aldehydes ((a) aliphatic aldehydes (eg, formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, isobutyraldehyde, etc.), (b) aromatic aldehydes (eg, benzaldehyde, etc.), (c) heterocyclic Aldehydes), (4) amines ((a) primary amines (eg, butylamine, ethylamine, propylamine, ethylenediamine), (b) secondary amines (eg, dibutylamine, diethylamine, dipropylamine) Etc.), (c) tertiary amines (for example, tributylamine, triethyl) (5) aminoaldehydes (for example, aminoacetaldehyde), (6) alkanolamines (for example, ethanolamine, diethanolamine, triethanolamine, etc.), (7) reducing sugar ( (E.g., sucrose, treperth, maltose, lactose, etc.), (8) hydrogen compounds (e.g., sodium borohydride, etc.), (9) low-order inorganic oxygen acids (e.g., sulfurous acid, nitrous acid, hyponitrous acid, phosphorous) Acid, hypophosphorous acid, etc.) and hydrates thereof (for example, hydrogen sulfite) or salts thereof (for example, alkali metal salts such as sodium), etc., and these may be used alone or in combination. .

  The reduction reaction can be carried out at any temperature, and when carried out in an aqueous medium, a temperature in the range of 5 to 90 ° C. is preferred because the reaction can proceed easily. The addition amount of the reducing agent can be appropriately set as long as it can be reduced to a metal, and is preferably 0.2 to 50 mol with respect to 1 mol of the metal compound. If the addition amount is less than 0.2 mol, it is not preferable because the reduction reaction does not proceed sufficiently, and if it exceeds 50 mol, the dispersion of the generated metal particles tends to become unstable, which is not preferable.

  It is preferable to adjust the pH of the mixed solution of the metal compound and the reducing agent to a range of 8 to 14 because the metal compound is uniformly dispersed in the medium and a reduction reaction is likely to occur. A more preferable pH range is 8 to 13, and 8 to 12 is more preferable. Specifically, for example, after adjusting the pH of the liquid medium containing the metal compound, the metal compound may be reduced, or after mixing the reducing agent, the pH may be adjusted. For pH adjustment, for example, a basic compound such as an alkali metal or alkaline earth metal hydroxide or carbonate such as sodium hydroxide, potassium hydroxide or calcium hydroxide, an ammonium compound such as ammonia, or an amine is used. be able to. Since the metal particles obtained in this way easily aggregate when the pH of the liquid medium is 5 or less, they can be separated by a relatively simple operation such as suction filtration or sedimentation separation. A more preferable pH range is 0-5. The colloidal metal colloid particles can be washed by a conventional method, and soluble salts and remaining reducing agent can be sufficiently removed. For pH adjustment, for example, an inorganic compound such as hydrochloric acid, sulfuric acid or nitric acid, or an acidic compound such as organic acid such as formic acid, acetic acid or propionic acid can be used.

  A compound containing at least one element selected from sulfur, nitrogen, and phosphorus (hereinafter sometimes referred to as a coordination compound) is preferably present on the surface of the metal particles. Since each element of sulfur, nitrogen, and phosphorus is coordinated and chemically bonded to the surface of the metal particle, the compound containing the elements of sulfur, nitrogen, and phosphorus is coordinated to the surface of the metal particle through these elements. Among these elements, sulfur is preferable because it has a strong chemical bonding force with metal particles.

  Examples of the sulfur compound include (a) mercaptocarboxylic acids (eg, mercaptopropionic acid, mercaptoacetic acid, thiodipropionic acid, mercaptosuccinic acid, dimercaptosuccinic acid, thioacetic acid, thiodiglycolic acid, etc.), (b) thio Glycols (eg, mercaptoethanol, thiodiethylene glycol, etc.), (c) aminothiols (aminoethyl mercaptan, thiodiethylamine, etc.), (d) thioamides (eg, thioformamide, etc.), (e) sulfur-containing amino acids ( For example, cysteine, methionine, etc.). Among them, at least one selected from mercaptopropionic acid, mercaptoacetic acid, thiodipropionic acid, mercaptosuccinic acid, mercaptoethanol, thiodiethylene glycol, thiodiglycolic acid, aminoethyl mercaptan, and thiodiethylamine is preferable, and mercaptopropionic acid, mercapto Acetic acid and mercaptoethanol are more preferred because they are effective in imparting dispersion stability to metal particles, particularly metal colloid particles.

  Examples of nitrogen compounds include (a) amino acids (for example, neutral amino acids such as glycine and alanine, basic amino acids such as histidine and arginine, and acidic amino acids such as aspartic acid and glutamic acid), (b) amino Polycarboxylic acids (for example, ethylenediaminetetraacetic acid (EDTA), nitrilotriacetic acid (NTA), iminodiacetic acid (IDA), ethylenediaminediacetic acid (EDDA), ethylene glycol diethyl etherdiaminetetraacetic acid (GEDA), etc.), (c) alkanolamine (For example, ethanolamine, diethanolamine, triethanolamine, etc.) and (d) amines (ethylenediamine, diethylenetriamine, triaminotriethylamine, etc.).

As the phosphorus compound, an alkyl phosphine _(-PR 3: R is an alkyl group).
Furthermore, a protective colloid may be present on the surface of the metal particles.
Examples of protective colloids include protein systems such as gelatin, gum arabic, casein, sodium caseinate, ammonium caseinate, natural polymers such as starch, dextrin, agar, sodium alginate, hydroxyethylcellulose, carboxymethylcellulose, methylcellulose, and ethylcellulose. Cellulose type such as polyvinyl alcohol, vinyl type such as polyvinyl alcohol, polyvinyl pyrrolidone, acrylic acid type such as sodium polyacrylate and ammonium polyacrylate, higher fatty acid such as stearic acid, synthetic polymer such as polyethylene glycol, and many such as citric acid Examples thereof include monovalent carboxylic acids, anilines or derivatives thereof, and one or more of these may be used. Since the protective colloid of a polymer has a high effect of dispersion stabilization, it is preferable to use this, and when reacting in an aqueous medium, it is preferable to use a water-soluble one, particularly gelatin, polyvinyl alcohol, polyvinyl pyrrolidone, Polyethylene glycol is preferred. Of these, lime-processed gelatin is preferable because of its high metal particle dispersion ability and antioxidant ability.

In order to chemically bond the coordination compound or protective colloid (hereinafter sometimes referred to as “coordination compound etc.”) to the surface of the metal particles in advance, the coordination compound is dispersed in a liquid medium in which the metal particles are dispersed. Or the like, or when a metal compound and a reducing agent are reacted in a liquid phase, a coordination compound or the like is present. The latter method is a preferable method because the above-mentioned coordination compound and the like are present in the reduction reaction, and highly dispersed metal particles can be obtained, and particularly fine metal colloidal particles can be obtained. From this, a method of reducing by mixing a reducing agent with a solution in which a metal compound and a coordination compound are dissolved in a medium, a reducing agent is added to a solution in which a metal compound and a coordination compound are dissolved in a medium. A method of adding and reducing is a more preferable method.
A coordination compound or the like is preferably present in a range of about 0.1 to 15 parts by weight with respect to 100 parts by weight of the metal particles because a desired effect can be obtained, and a more preferable range is 0.1 to 10 parts by weight. Degree. In addition, when using a protective colloid, even if it is the same kind as an adhesive imparting agent, since the function is different due to the difference in the step of addition, it is not added to the amount of the adhesive imparting agent.

(2) Solvent Water and / or an organic solvent can be used for the solvent mix | blended with metal ink. As the organic solvent, a commonly used organic solvent can be appropriately selected and used. Specific examples of the organic solvent include toluene, xylene, solvent naphtha, normal hexane, isohexane, cyclohexane, methylcyclohexane, normal heptane, tridecane, tetradecane, pentadecane and other hydrocarbon solvents, methanol, ethanol, butanol, IPA (isopropyl). Alcohols such as alcohol), normal propyl alcohol, 2-butanol, TBA (tertiary butanol), butanediol, ethylhexanol, benzyl alcohol, terpineol (boiling point: 217-218 ° C), dihydroterpineol (boiling point: about 200 ° C) Ketones such as solvents, acetone, methyl ethyl ketone, methyl isobutyl ketone, DIBK (diisobutyl ketone), cyclohexanone, DAA (diacetone alcohol) Solvent, ethyl acetate, butyl acetate, methoxybutyl acetate, cellosolve acetate, amyl acetate, normal propyl acetate, isopropyl acetate, methyl lactate, ethyl lactate, butyl lactate, and other ester solvents, methyl cellosolve, cellosolve, butyl cellosolve, dioxane, MTBE (Methyl tertiary butyl ether), ether solvents such as butyl carbitol (boiling point: 230.6 ° C), glycol solvents such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, diethylene glycol monomethyl ether (boiling point: 194 ° C) , Triethylene glycol monomethyl ether (boiling point: 249 ° C), dipropylene glycol monomethyl ether (boiling point: 189-190 ° C), 3-methoxy-3-methyl-1-buta Glycol ether solvents such as ethylene glycol monomethyl ether acetate, PMA (propylene glycol monomethyl ether acetate), diethylene glycol monoethyl ether acetate (boiling point: 217.4 ° C), diethylene glycol monobutyl ether acetate (boiling point: 246.8 ° C) Glycol ester solvents such as formamide (boiling point: 210 ° C), N-methylformamide (boiling point: 197 ° C), N, N-dimethylformamide (boiling point: 197 ° C), acetamide, N-methylacetamide (boiling point: 205 ° C) ), N, N-dimethylacetamide, N-methylpropionamide, N-methylpyrrolidone (boiling point: 202 ° C.), 1,3-dimethyl-2-imidazolidinone (boiling point: 226 ° C.), furfural (boiling point) : 161 ° C.) of at least one selected from an amide solvent or the like can be used. In the present invention, one selected from ether solvents, glycol ester solvents and amide solvents is preferred, and amide solvents are more preferred. Moreover, what has a comparatively high boiling point is preferable regarding the boiling point of an organic solvent, a thing with a boiling point of 185-250 degreeC is more preferable, and a thing with 200-250 degreeC is still more preferable.

(3) Polyether Polyether is for increasing the viscosity of the metal ink.
The polyether is a linear polymer having an ether bond —R—O—R— in the main chain, and the repeating unit is preferably an alkylene group having 2 to 6 carbon atoms. Examples of such polyethers include polyethylene oxide, polyethylene glycol, polypropylene oxide, polypropylene glycol, polybutylene glycol, and the like. Polyethylene oxide and polyethylene glycol are more preferable because of their high additive effect. Further, the polyether may be a binary copolymer or polyether block copolymer. For example, ethylene glycol / propylene glycol, ethylene glycol / butylene glycol binary copolymer, ethylene glycol / propylene glycol / ethylene glycol, propylene glycol / ethylene glycol / propylene glycol, ethylene glycol / butylene glycol / ethylene glycol, etc. Ternary copolymers are mentioned. The block copolymer includes binary block copolymers such as polyethylene glycol polypropylene glycol and polyethylene glycol polybutylene glycol, polyethylene glycol polypropylene glycol polyethylene glycol, polypropylene glycol polyethylene glycol polypropylene glycol, polyethylene glycol polybutylene glycol polyethylene glycol 3 and the like. For example, original block copolymer may be used.

Moreover, although a polyether is based also on the chemical structure, its viscosity average molecular weight is preferable about 100,000-5,000,000. When the viscosity average molecular weight is less than 100,000, the effect of thickening per unit added weight part is small, and it is necessary to add more than 20 parts by weight, and the characteristics such as mirror gloss and conductivity of the film are likely to be deteriorated. . On the other hand, if the viscosity average molecular weight is larger than 5,000,000, handling during ink production, printing and painting becomes difficult. More preferably, it is the range of 100,000-4,000,000, More preferably, it is the range of 500,000-3,000,000.
The viscosity average molecular weight Mv can be determined by calculating the intrinsic viscosity number η of a polyethylene oxide aqueous solution at a temperature of 30 ° C., and using the formula: η = K · Mv ^α . The measuring method of the intrinsic viscosity η is defined in “JIS K7367-3 1999”.

(4) Adhesion imparting agent
The adhesion-imparting agent is for improving the adhesion between the metal particles and the base material, and any one can be used as long as it has an effect of imparting adhesion such as a polymer having a binder action.

As the adhesion-imparting agent having a good effect in the range of the blending amount of the present invention, a polymer having a CO double bond in the unit structure is preferable, and specifically, polyester, protein, polyketone, polyamide and the like can be used. .
Polyester is a polymer having an ester bond —CO—O— in the main chain, and is a polycondensate of polycarboxylic acid (dicarboxylic acid) and polyalcohol (diol), or polyalkylene glycol in the polyester resin. , Copolyesters copolymerized with dicarboxylic acids, etc., vinyl modified by reacting polyester resins with vinyl polymerizable monomers, epoxy resins modified with epoxy compounds, or urethane modified with isocyanate compounds, aromatic dicarboxylic acids and carbon The polyester diol etc. which reacted with the aliphatic diol of several 2-6 can be used.
A protein is a polymer having a peptide bond —CO—NH—, and includes a product obtained by further hydrolyzing the protein. Specifically, gelatin, a product obtained by further hydrolyzing gelatin, gum arabic, casein, sodium caseinate, ammonium caseinate and the like can be used.
The polyketone is a copolymer of an olefin having a ketone group and carbon monoxide, and an ethylene-carbon monoxide copolymer, an ethylene-propylene-carbon monoxide copolymer, or the like can be used.
Polyamide is a linear polymer whose main chain is composed of repeating amide bonds —CO—NH—, and uses an aliphatic polyamide such as nylon 6 or an aromatic polyamide such as Kevlar (registered trademark). Can do.

The adhesiveness imparting agent is preferably at least one selected from polyester and protein, and more preferably polyester.
When polyester is used, the factor is unknown, but it is preferable to combine with a polyether as a viscosity-imparting agent because the adhesion-imparting effect is remarkably enhanced. Specific examples include copolymer polyester resins such as Byron and Byronal manufactured by Toyobo Co., Ltd.

(5) Other components In the metal ink of the present invention, as other components, a crosslinking agent, a surface conditioner (leveling agent), an antifoaming agent, a surfactant, a polymer dispersant, a non-surface active dispersant, Additives such as a curable resin, a plasticizer, and an antifungal agent can be appropriately blended as necessary.

The cross-linking agent can perform a cross-linking reaction when a film is produced, and can be blended as necessary because the adhesion to the substrate is further improved. The crosslinking agent is at least one selected from an oxazoline group (—CONC ₂ ), a carbodiimide group (—N═C═N—), a blocked isocyanate group, an epoxy group (—COC), a carbonyl group (—C═O), and the like. Cross-linking agents with some active groups are preferred. Moreover, 1 type of compounds chosen from a melamine and a melamine derivative can also be used as a crosslinking agent. Specifically, as the oxazoline-based crosslinking agent, 2,2′-bis (2oxazoline), 2,2′-methylene-bis (2oxazoline), 2,2′-ethylene-bis (4,4′dimethyl) -2oxazoline), 2,2'-phenylene-bis (2oxazoline), bis (2-oxazolinecyclohexanone) sulfide, and the like. Examples of the carbodiimide-based crosslinking agent include condensates of diisocyanate compounds such as xylene diisocyanate, hexamethylene diisocyanate, tolylene diisocyanate, and isophorone diisocyanate. Examples of the blocked isocyanate crosslinking agent include those obtained by blocking the isocyanate group (—N═C═O) of the above-mentioned diisocyanate compound with a blocking agent such as alcohol, phenol, oxime, or acid amide. Examples of the epoxy-based crosslinking agent include ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, 1,6-hexanediol glycidyl ether, and glycidyl acrylate. Examples of carbonyl crosslinking agents include aldehyde compounds such as formaldehyde, glyoxal, and glutaraldehyde, ketone compounds such as diacetone, cyclopentadione, diacetone acrylamide, adipic acid hydrazide, acetoacetoxyethyl methacrylate, and allyl acetoacetate. It is done. Examples of the melamine crosslinking agent include melamine, a methylolated melamine derivative obtained by condensing melamine and formaldehyde, a compound partially or completely etherified by reacting a methylolated melamine with a lower alcohol, and a mixture thereof. . These active groups may be contained in one or more kinds of cross-linking agents, and two or more cross-linking agents having different active groups may be used, or different types of cross-linking agents having the same active group. Two or more of these can also be used.

  When blending a cross-linking agent, it is preferable to use a polyester as the adhesion-imparting agent because it reacts with each other to further improve the adhesion, and it is more preferable to use a polyester having a hydroxyl group at the molecular end. This is even more effective when a plastic film such as PET (polyethylene terephthalate) or PEN (polyethylene naphthalate) is used as the substrate.

  The surface conditioner controls the surface tension of the metal ink to prevent defects such as repellency and crater. Acrylic surface conditioner, vinyl surface conditioner, silicone surface conditioner, fluorine surface conditioner Etc. The antifoaming agent is for suppressing the amount of bubbles generated when the components to be blended in the metal ink are mixed, and a silicone-based antifoaming agent or the like can be used. Surfactants are preferable because they have the effect of further improving the dispersion stability of metal particles and the effect of controlling the rheological properties of metal inks and improving the coating properties. Specifically, cations such as quaternary ammonium salts are preferred. Use of known surfactants such as anion, ether, ether ester, ester, nitrogen-containing nonionics such as carboxylic acid, carboxylate, sulfonate, sulfate ester, phosphate ester, etc. The polymer dispersant is for suppressing aggregation of metal particles, and a known one can be used. One or more selected from these can be used. The blending amount of the surface conditioner (leveling agent), antifoaming agent, surfactant and the like can be appropriately set according to the metal ink composition, but is generally 0.01 with respect to 100 parts by weight of the metal particles. A range of about 0.5 parts by weight is preferred.

  In the metal ink of the present invention, a predetermined amount of metal particles, a solvent, a polyether, an adhesion-imparting agent, and, if necessary, other blends are mixed by a known method to disperse the metal particles in the solvent. As a mixing method, for example, a method such as stirring and mixing using a stirrer such as a disper, or wet pulverization and mixing such as a mixer, a sand mill, or a colloid mill can be used.

  The amount of metal particles, polyether, adhesion promoter, solvent, etc. to be blended in the metal ink depends on the ink viscosity required depending on the printing machine or coating machine used, the performance of the resulting metal-containing film, etc. It is preferable to set as follows.

  The polyether is used to increase the viscosity of the metal ink, and can be adjusted to a viscosity according to the printing machine or coating machine by appropriately adjusting the content. Although depending on the amount of metal particles and the amount of solvent, increasing the polyether content increases the ink viscosity and makes it easy to select a usable printing machine or coating machine. The characteristics such as properties are likely to deteriorate. On the other hand, if the content of the polyether is reduced, the properties such as mirror gloss and conductivity of the metal-containing film are enhanced, but the ink viscosity is lowered and it is difficult to select a usable printing machine or coating machine. For this reason, the range of 0.5-20 weight part with respect to 100 weight part of said metal particles is important for content of polyether, and the range of 0.5-10 weight part is preferable.

  The content of the adhesion-imparting agent can also be adjusted as appropriate. However, when the content is increased, the adhesion is improved, but the properties such as mirror gloss and conductivity of the metal-containing film are likely to deteriorate. On the other hand, if the content of the adhesiveness-imparting agent is reduced, the metal-containing film has properties such as specular gloss and conductivity, but the adhesiveness tends to be lowered. For this reason, the range of 0.1-20 weight part is important with respect to 100 weight part of metal particles, and the range of 0.1-6 weight part is preferable with respect to 100 weight part of metal particles.

  The total amount of the polyether and the adhesion-imparting agent can be adjusted as appropriate. However, if the total amount is too large, characteristics such as mirror gloss and conductivity of the metal-containing film are likely to deteriorate. On the other hand, if the total amount is too small, it is difficult to recognize a synergistic effect on the adhesion between the polyether and the adhesion-imparting agent. For this reason, the total amount of the polyether and the adhesion-imparting agent is important in the range of 0.6 to 20.5 parts by weight with respect to 100 parts by weight of the metal particles, and the range of 0.6 to 10.5 parts by weight. preferable.

  The crosslinking agent can be blended as necessary, but the content thereof is preferably 5 parts by weight or less with respect to 100 parts by weight of the metal particles, and particularly 2 parts by weight when using polyester as an adhesion promoter. The following is more preferable. When the amount of the crosslinking agent is more than 5 parts by weight, it is difficult to obtain a specular gloss and the properties such as conductivity are also deteriorated. Furthermore, when mix | blending a crosslinking agent, it is preferable that the total amount of a polyether, adhesiveness imparting agent, and a crosslinking agent is 20 weight part or less.

  The content of the metal particles can also be adjusted as appropriate. The higher the content, the higher the ink viscosity, and the better the gloss and conductivity of the metal-containing film. For this reason, the content of the metal particles is preferably 5% by weight or more based on the metal ink. On the other hand, if the content of the metal particles is too large, the ink viscosity becomes too high and the printability and paintability are hindered, so 90% by weight or less is preferable.

  The content of the solvent can be appropriately set. For example, it is preferably 95% by weight or less based on the metal ink. If the content of the organic solvent is more than 95% by weight, the viscosity of the metal ink becomes too low, which is not preferable.

The metal ink of the present invention can be adjusted to a wide range of viscosities by appropriately setting the blending of various materials within the aforementioned range.
Specifically, it can be adjusted to a range of 500 to 200,000 mPa · s when expressed by a viscosity measured at 25 ° C. and a shear rate of 7.5 sec ⁻¹ with a rotational viscometer (DV-I + manufactured by Brookfield). it can. The range of 1000 to 10000 mPa · s is preferable, and the range of 1000 to 5000 mPa · s is more preferable.

  Next, after printing or painting the metal ink of the present invention on a substrate, the metal-containing film can be obtained by removing the solvent.

  Examples of the general-purpose printing machine used for printing on the substrate include a screen printing machine, a gravure printing machine, a flexographic printing machine, an inkjet printing machine, and an offset printing machine. In addition, as a general-purpose coating machine used for painting, a spray coating machine, a slit coater, a curtain coater, a bar coater, a spin coater, etc. can be mentioned, and in addition, a brush, a spatula, a trowel, a roller, a pen, a brush or the like is used. Can also be painted. The metal ink of the present invention is particularly suitable for a screen printing machine.

Moreover, you may heat the metal containing film | membrane produced by printing or coating the metal ink of this invention on a base material as needed. By the heating, organic compounds blended in the ink such as the polyether and the adhesion-imparting agent and / or the cross-linking agent cause a reaction such as cross-linking with each other to improve the adhesion, and the metal particles are partially fused. It is presumed that characteristics such as mirror gloss and conductivity of the metal-containing film are further improved.
The heating temperature depends on the heat-resistant temperature of the substrate and the metal species, but can be set as appropriate. For example, the heating temperature is preferably 200 ° C. or lower, and more preferably about 50 to 150 ° C. The heating time can also be appropriately set, and for example, about 5 minutes to 10 hours is appropriate.
The atmosphere can also be set as appropriate, and can also be carried out in an inert gas atmosphere, a reducing gas atmosphere, or an oxygen-containing atmosphere (such as in the air). As the inert gas, N ₂ gas, Ar gas, He gas, or the like can be used.

The film thus obtained can be used for electrical continuity, antistatic, electromagnetic wave shielding or metallic luster, specular gloss, and the like, and further can be used for electrodes, circuit wiring patterns, and the like.
In particular, the metal ink of the present invention is suitably used for forming a decorative film and imparting a metallic specular gloss, and can be used as a decorative article in which the metal color of the metal particles and the specular gloss are imparted to the substrate surface. In addition to coloring and giving gloss to at least part of the surface of the base material or the entire surface of the base material using metal ink, a design, a mark, or a logo mark is formed on a part of the surface of the base material. Or other characters, figures and symbols can be formed. Moreover, since the metal containing film produced using the metal ink of this invention is excellent in adhesiveness with a base material, it can also endure the deformation process after film formation. Therefore, it is possible to introduce a metal-containing film forming process at any stage in the production stage of the product, and to form a film on the raw material base material before processing the base material into a use article, or to decorate it, or It is also possible to decorate any article after processing the substrate. Furthermore, it is also possible to decorate the surfaces of those substrates previously coated with metal ink.

  The specular gloss of the obtained metal-containing film can be judged using a spectral colorimeter. When the metal ink of the present invention is used, a metal-containing film having a glossiness of 400 or more can be produced according to JIS Z 8741 when the incident angle and the reflection angle are measured at 20 degrees. Can be used for decoration purposes.

  A method in accordance with JIS K 5600-5-6 for the obtained metal-containing film (making a grid with a cutter knife, applying a cellophane tape, then peeling the cellophane tape, and the number of coating film pieces remaining thereafter 70% or more of grids remain and have industrially sufficient adhesion. The residual rate is more preferably 80% or more.

  As the base material, use inorganic materials such as metals, glass, ceramics, concrete, organic materials such as rubber, plastic, paper, wood, leather, cloth, and fibers, and materials that use a combination of inorganic materials and organic materials or composite materials. Can do.

As a specific example of an article to be decorated,
(1) Exteriors, interiors, bumpers, door knobs, side mirrors, front grills, lamp reflectors, display devices, etc. for transportation equipment such as automobiles, trucks, and buses,
(2) Exteriors of electrical appliances such as TVs, refrigerators, microwave ovens, personal computers, mobile phones, cameras, remote controls, touch panels, front panels, etc.
(3) Houses, buildings, department stores, stores, shopping malls, pachinko shops, wedding halls, funeral halls, exteriors of buildings such as shrines and temples, window glass, entrances, nameplates, gates, doors, doorknobs, show windows, interiors, etc. ,
(4) Lighting equipment, furniture, furniture, toilet equipment, Buddhist altar tools, Buddhist statues and other home equipment
(5) Fixtures such as hardware and tableware,
(6) Vending machines for drinking water, tobacco, etc.
(7) Containers for synthetic detergents, skin care, soft drinks, alcoholic beverages, confectionery, food, tobacco, pharmaceuticals,
(8) Packing tools such as cover paper and cardboard boxes,
(9) Costumes and accessories such as clothes, shoes, bags, glasses, artificial nails, artificial hair, jewelry,
(10) Sports equipment such as baseball bats and golf clubs, hobby goods such as fishing equipment,
(11) Office supplies such as pencils, colored paper, notebooks, New Year postcards, desks and chairs,
(12) Books covers and covers, dolls, toys such as minicars, cards such as commuter passes, recording media such as CDs and DVDs, and the like. In addition, human nails, skin, eyebrows, hair, and the like can be used as a base material.

  The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.

(Preparation of metal colloidal particles)
50 g of silver nitrate as a metal compound and 1.6 g of 3-mercaptopropionic acid as a coordination compound were dissolved in 220 ml of pure water, and 70 ml of 28% ammonia water was added to adjust the pH to 11.6. On the other hand, 2.1 g of sodium borohydride as a reducing agent was dissolved in 295 ml of pure water to which 4 ml of 28% ammonia water was added. Both were dripped simultaneously in 600 milliliters of pure water over 30 minutes, and silver nitrate was reduced to produce silver colloidal particles having 3-mercaptopropionic acid on the surface in the medium. Next, the medium liquid of the obtained silver colloid particles is adjusted to pH 2.5 with nitric acid (30%), the silver colloid particles are settled, and the silver colloid particles (silver colloid particles are collected by a vacuum filter). 3 parts by weight of mercaptopropionic acid with respect to 1000 parts by weight of the particles.The average particle diameter of the silver colloidal particles is about 10 nm), and after washing with water until the specific conductivity of the filtrate is 10 μS / cm or less, Re-dispersion in N-methylformamide gave a silver colloid solution (containing 70% by weight of silver colloid particles).

(Vehicle preparation)
In a plastic cup, formamide 2.23 g, surface tension modifier (BYK-190 BYK-190) 0.07 g, water-dispersed polyester (Toyobo Co., Ltd. Vylonal (registered trademark) MD-1100, polyester content 30 weight) %) 1.85 g was measured and stirred, and then 1.03 g of polyethylene oxide (PEO (registered trademark) -3Z, manufactured by Sumitomo Seika Chemical Co., Ltd., molecular weight: 600,000 to 1,100,000) was added to N-methyl. A solution dissolved in 4.80 g of formamide was added and mixed with a stirring deaerator to obtain a vehicle.

(Preparation of ink)
The silver colloid solution 7.2g obtained by the said method, the vehicle 1.8g, and N-methylformamide 0.9g were mixed with the stirring defoamer, and the silver ink of this invention was obtained.

  In Example 1, except that polyethylene oxide is replaced with 0.78 g of polyethylene oxide having a molecular weight of 1,700,000 to 2,200,000 (PEO-8Z manufactured by Sumitomo Seika), the same conditions as in Example 1 are used. An inventive silver ink was obtained.

  In Example 1, the silver ink of this invention was obtained on the same conditions as Example 1 except having changed the usage-amount of water-dispersed polyester from 1.85g to 5.55g.

  In Example 1, 0.02 g (0.4 parts by weight with respect to 100 parts by weight of silver) of a blocked isocyanate (Elastotron (registered trademark) BN-77 manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) was further added as a crosslinking agent. The silver ink of the present invention was obtained under the same conditions as in Example 1.

Comparative Example 1
In Example 1, the comparative silver ink was obtained on the same conditions as Example 1 except having changed the usage-amount of water-dispersed polyester from 1.85g to 65.0g.

Comparative Example 2
In Example 1, the comparative silver ink was obtained on the same conditions as Example 1 except not adding water-dispersed polyester.

Comparative Example 3
In Example 1, a comparative silver ink was obtained under the same conditions as in Example 1 except that polyethylene oxide was not used.

Comparative Example 4
In Example 1, the comparative silver ink was obtained on the same conditions as Example 1 except not adding water-dispersed polyester and polyethylene oxide.

(Viscosity measurement)
The measurement was performed with a rotational viscometer (DV-I + manufactured by Brookfield) at 25 ° C. and a shear rate of 7.5 sec ⁻¹ .

  Table 1 shows the blending amount of each blend with respect to 100 parts by weight of silver.

  Table 1 shows the viscosity of each silver ink. It can be seen that the viscosity of the silver ink of the present invention can be adjusted as appropriate, and specifically, it can be adjusted in the range of 1500 to 2500 mPa · s only by slightly adjusting the amount of polyether.

(Preparation of coating film)
The obtained ink was dropped on a PET film (Lumilar (registered trademark) T60 manufactured by Toray Industries, Inc.), spread to a thickness of about 7 μm using a bar coater (# 3), and heated in an oven at 100 ° C. for 30 minutes to produce silver. A coating film was prepared.

(Evaluation of adhesion)
According to JIS K5600-5-6, the obtained silver coating film is made of 25 square grids with a cutter knife, applied with cellophane tape, peeled off, and the number of coating grid grid pieces remaining thereafter It was evaluated with. It is 0/25 when all peels and 25/25 when all remains, and the larger this value, the higher the adhesion between the silver-containing film and the substrate.

(Evaluation of metallic mirror gloss)
The glossiness of the obtained silver coating film was measured by a method based on JIS Z 8741 under the condition that both the incident angle and the reflection angle were 20 degrees. A spectrocolorimeter (SD5000) manufactured by Nippon Denshoku Industries Co., Ltd. was used for the measurement.

(Appearance evaluation)
The color tone and homogeneity of the obtained silver coating film were visually observed. The homogeneity was judged by the presence or absence of uneven color and repellency of the coating film.

  The cross-cut piece residual rate in the cross-cut test of the silver-containing film obtained in the example is 85 to 100%, which indicates that sufficient adhesion is obtained.

  In addition, the specular gloss of the silver-containing films obtained in the examples is 800 or more, and it can be seen that sufficient metallic luster is obtained.

  Furthermore, it can be seen that the silver-containing films obtained in the examples have no color unevenness, repelling, etc., and have a silver color tone.

In the present invention, by blending a certain amount of both the polyether and the adhesion-imparting agent, not only can a high-viscosity metal ink be produced, but also the adhesion and appearance of the metal-containing film using the metal ink and the substrate It can be seen that these effects can be achieved in a smaller amount than when a polyether or an adhesion-imparting agent is individually added.

  The metal ink of the present invention is a general-purpose printing machine such as a screen printing machine, a gravure printing machine, a flexographic printing machine, an inkjet printing machine or an offset printing machine, a general-purpose machine such as a spray, slit coater, curtain coater, bar coater, or spin coater. A material that ensures electrical continuity, or is antistatic, because it can be printed or coated on a substrate without uneven printing or coating using a coating machine, brush, spatula, trowel, roller, pen or brush, etc. Widely used for applications such as electromagnetic shielding or metallic luster. In addition, a coating film with excellent conductivity and metallic luster can be obtained by heating at a relatively low temperature, so that it can be applied to new applications of nanotechnology such as formation of electrodes and circuit wiring patterns that have been actively developed in recent years. Can also be applied, and can also be applied to alternative uses of plating technology such as design and decorativeness by metallic mirror gloss.

Claims (10)

Metal particles, a solvent, 0.5 to 20 parts by weight of polyethylene oxide with respect to 100 parts by weight of the metal particles, and at least 0.1 to 20 parts by weight of polyester with respect to 100 parts by weight of the metal particles. In addition, the total amount of polyethylene oxide and polyester is 0.6 to 20.5 parts by weight with respect to 100 parts by weight of metal particles, and the viscosity average molecular weight of polyethylene oxide is in the range of 100,000 to 5,000,000. A certain metal ink. The metal ink according to claim 1, comprising an amide solvent. The metal ink according to claim 1 or 2 , wherein the constituent component of the metal particles is at least one selected from copper, silver, gold, nickel, palladium, and platinum. A method for producing a metal-containing film, wherein the metal ink according to any one of claims 1 to 3 is printed or coated on a substrate. Manufacturing of claims after printing or painting a metal ink according to the substrate to any one of claims 1 to 3, the metal-containing film according to claim 4, characterized in that the heat treatment at 200 ° C. below the temperature Method. A decorative film produced using the metal ink according to any one of claims 1 to 3 . The decorative film according to claim 6 , which has a coating film having a specular gloss of 400 or more measured under conditions of an incident angle and a reflection angle of 20 degrees in a spectrocolorimeter. An electrode manufactured using the metal ink according to any one of claims 1 to 3 . A wiring pattern produced using the metal ink according to any one of claims 1 to 3 . A component having the decorative film, electrode, or wiring pattern according to any one of claims 6 to 9 .