JP2010024526A - Copper particulate dispersion and production method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a copper particulate dispersion which has less possibility of being contaminated by impurities of inorganic components and has been produced with a safe method, and to provide a production method therefor. <P>SOLUTION: The copper particulate dispersion containing a hydrazine derivative and copper particulates is produced with a method comprising the steps of: (a) mixing a precursor of the copper particulates with the hydrazine derivative; and (b) adding water to the obtained mixture and heating the resulting mixture to reduce the precursor and deposit the copper particulates. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a copper fine particle dispersion and a method for producing the same. The copper fine particle dispersion of the present invention can be suitably used as a conductive ink or conductive paste which is a circuit pattern forming material for a wiring board, particularly in the electronics field.

  2. Description of the Related Art In recent years, a technique for forming a wiring pattern on a circuit board by forming a desired pattern using a conductive material containing fine metal particles by an ink jet printing method or a screen printing method (conducting pattern forming technology) has attracted attention. . At present, the conductive materials (compositions for forming conductive patterns) used for this purpose are mainly those containing silver fine particles, but there is a problem that electromigration occurs in silver, so the cost can be reduced. It is desired to use copper fine particles that are capable of being produced and that are free from the occurrence of electromigration, in the form of ink or paste.

  However, copper is easily oxidized, and the tendency becomes more remarkable with nano-sized copper fine particles. Oxidized copper has a significant decrease in electrical conductivity. Therefore, in order to use copper fine particles as ink or paste, preventing oxidation while maintaining dispersibility is a major issue.

  In order to solve such problems, as an antioxidant, an organic compound having a nitrogen atom in the molecular structure is allowed to coexist with the copper fine particles and adsorbed on the surface of the copper metal, thereby preventing the copper fine particles from contacting oxygen and water. At the same time, a method for preventing coagulation of copper fine particles and maintaining dispersibility has been studied. For example, as an antioxidant, a method using alkylamine (for example, Patent Document 1) and a method using benzotriazole (for example, Patent Document 2) are known.

  However, for example, in the method described in Patent Document 1, since sodium borohydride is used as a reducing agent, boron compounds and sodium ions may remain as impurities even after purification. Use of may be restricted. Further, for example, in the method described in Patent Document 2, hydrazine that does not leave an impurity component is used as a reducing agent. However, it is necessary to add a large amount of hydrazine in a short time at the time of production. There was a problem that it was very dangerous.

  As described above, the conventional methods are not sufficient, and further studies are required industrially.

JP 2007-32215 A JP 2004-211108 A

  The present invention has been made in view of the above-described background art, and an object thereof is to provide a copper fine particle dispersion produced by a safe method without the possibility of mixing of inorganic impurities and a production method thereof. It is in.

  As a result of intensive studies on the copper fine particle dispersion and the production method thereof, the present inventors have found that the above-mentioned problems can be solved by a copper fine particle dispersion containing a specific hydrazine derivative and copper fine particles, and have completed the present invention. It was.

  That is, the present invention relates to a copper fine particle dispersion and a production method thereof, a copper fine particle and a production method thereof, and a conductive pattern forming composition as described below.

  [1] The following general formula (1)

[In General Formula (1), R _{1 to} R ₄ are each independently a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, an aromatic group having 5 to 10 carbon atoms, or an alkyl having 1 to 4 carbon atoms. Group having 5 to 10 carbon atoms substituted with 1 to 3 hydrogen atoms on the aromatic ring, or 1 to 4 carbon atoms having 1 to 3 hydrogen atoms substituted with an aromatic group having 5 to 10 carbon atoms Represents an alkyl group. However, R _{1 to} R ₄ are not all hydrogen atoms. ]
A copper fine particle dispersion containing a hydrazine derivative represented by the formula (1) and copper fine particles having an average particle diameter in the range of 1 to 1000 nm.

[2] In general formula (1), R ₁ and R ₂ are each independently a hydrogen atom, a methyl group, an ethyl group, a linear, branched or cyclic alkyl group having 3 to 18 carbon atoms, carbon An aromatic group having 5 to 10 carbon atoms, an aromatic group having 5 to 10 carbon atoms in which hydrogen on the aromatic ring is substituted by 1 to 3 with a methyl group, a methyl group having 1 to 3 hydrogen atoms substituted with a phenyl group, or phenyl In the above [1], an ethyl group in which a hydrogen atom is substituted by 1 to 3 by a group (provided that R ₁ and R ₂ do not simultaneously become a hydrogen atom), and R ₃ and R ₄ are hydrogen atoms. The copper fine particle dispersion as described.

[3] In General Formula (1), R ₁ and R ₂ are each independently a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, an i-butyl group, sec-butyl group, t-butyl group, n-pentyl group, i-pentyl group, neo-pentyl group, t-pentyl group, n-hexyl group, i-hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group, cyclohexyl group, phenyl group, 4-methylphenyl group, benzyl group, or 2-phenylethyl group (provided that R ₁ , R ₂ is not a hydrogen atom at the same time.), The copper fine particle dispersion according to [1] or [2], wherein R ₃ and R ₄ are hydrogen atoms.

  [4] The copper fine particle dispersion according to any one of the above [1] to [3], which contains 5 to 10,000% by weight of a hydrazine derivative with respect to the copper fine particles.

  [5] The method for producing a copper fine particle dispersion according to any one of the above [1] to [4], comprising the following steps a) and b).

  a) A step of mixing a hydrazine derivative represented by the general formula (1) and a copper fine particle precursor.

  b) A step of reducing and precipitating copper fine particles by adding water to the mixture obtained in step a) and heating the mixture.

  [6] The copper fine particle precursor is one or more compounds selected from the group consisting of copper oxide, copper hydroxide, copper halide, copper inorganic acid salt, copper organic acid salt and copper chelate complex. The manufacturing method of the copper fine particle dispersion as described in said [5].

  [7] Copper fine particle precursor is cuprous oxide, copper oxide, copper hydroxide, copper nitrate, basic copper carbonate, copper formate, copper acetate, copper propionate, copper butyrate, copper isobutyrate, copper valerate, iso Copper fine particles according to [5] above, which are one or more selected from the group consisting of copper valerate, copper pivalate, copper oxalate, copper malonate, copper benzoate, copper citrate and copper acetylacetonate. A method for producing a dispersion.

  [8] A conductive pattern forming composition comprising the copper fine particle dispersion according to any one of [1] to [4].

  [9] Copper fine particles having an average particle diameter in the range of 1 to 1000 nm, the following general formula (1)

[In General Formula (1), R _{1 to} R ₄ are each independently a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, an aromatic group having 5 to 10 carbon atoms, or an alkyl having 1 to 4 carbon atoms. Group having 5 to 10 carbon atoms substituted with 1 to 3 hydrogen atoms on the aromatic ring, or 1 to 4 carbon atoms having 1 to 3 hydrogen atoms substituted with an aromatic group having 5 to 10 carbon atoms Represents an alkyl group. However, R _{1 to} R ₄ are not all hydrogen atoms. ]
Copper fine particles whose copper fine particle surface is coated with a hydrazine derivative represented by

  [10] The method for producing copper fine particles according to [9], wherein the copper fine particles are separated from the copper fine particle dispersion according to any one of [1] to [4] by a separation operation.

  [11] The method for producing copper fine particles according to [10], wherein the separation operation is filtration, centrifugation, or distillation of components other than the copper fine particles.

  [12] A conductive pattern forming composition comprising the copper fine particles according to [9] above and a dispersant for dispersing the copper fine particles.

  In the copper fine particle dispersion of the present invention, since the hydrazine derivative acts as a reducing agent and an antioxidant and it is not necessary to add a reducing agent, there is no possibility that an inorganic impurity component is mixed in, and it can be used in the field of electronic materials. There is no risk of restriction.

  The method for producing a copper fine particle dispersion of the present invention is excellent in safety because the hydrazine derivative acts as a reducing agent and an antioxidant, and does not require the installation of a special reaction apparatus, reducing capital investment and utility costs. I can plan.

  Further, the copper fine particles separated from the copper fine particle dispersion of the present invention by the separation operation can be easily redispersed with an organic solvent or the like because the surface of the particles is coated with a hydrazine derivative.

  Furthermore, since the present invention utilizes a hydrazine derivative that can be obtained and manufactured at a low price, it is excellent in cost.

  The present invention is described in further detail below.

  In the copper fine particle dispersion of the present invention, the hydrazine derivative means the following general formula (1)

[In General Formula (1), R _{1 to} R ₄ are each independently a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, an aromatic group having 5 to 10 carbon atoms, or an alkyl having 1 to 4 carbon atoms. Group having 5 to 10 carbon atoms substituted with 1 to 3 hydrogen atoms on the aromatic ring, or 1 to 4 carbon atoms having 1 to 3 hydrogen atoms substituted with an aromatic group having 5 to 10 carbon atoms Represents an alkyl group. However, R _{1 to} R ₄ are not all hydrogen atoms. ]
It is a 1 type, or 2 or more types of compound chosen from the group which consists of a compound shown by these.

In the copper fine particle dispersion of the present invention, the hydrazine derivative is not particularly limited. However, in view of reducing power, decomposability and removability of decomposition products, in the above general formula (1), the substituent R ₁ , R ₂ is each independently a hydrogen atom, a methyl group, an ethyl group, a linear, branched or cyclic alkyl group having 3 to 18 carbon atoms, an aromatic group having 5 to 10 carbon atoms, and a methyl group. An aromatic group having 5 to 10 carbon atoms in which 1 to 3 hydrogen atoms on the ring are substituted, a methyl group in which 1 to 3 hydrogen atoms are substituted with a phenyl group, or an ethyl group in which 1 to 3 hydrogen atoms are substituted with a phenyl group (Wherein R ₁ and R ₂ are not hydrogen atoms at the same time), and the substituents R ₃ and R ₄ are one or more compounds selected from the group consisting of compounds that are hydrogen atoms Is preferable, and in the general formula (1), Substituent _R 1, _{R 2} are each independently a hydrogen atom, a methyl group, an ethyl group, n- propyl group, i- propyl, n- butyl group, i- butyl group, sec- butyl group, t- butyl group N-pentyl group, i-pentyl group, neo-pentyl group, t-pentyl group, n-hexyl group, i-hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group , N-undecyl group, n-dodecyl group, cyclohexyl group, phenyl group, 4-methylphenyl group, benzyl group, or 2-phenylethyl group (provided that R ₁ and R ₂ are simultaneously hydrogen atoms) It is more preferable that the substituents R ₃ and R ⁴ be one or two or more compounds selected from the group consisting of compounds each having a hydrogen atom.

In the copper fine particle dispersion of the present invention, as the hydrazine derivative represented by the general formula (1), for example, as the hydrazine derivative in which the substituents R ₁ , R ₃ and R ₄ are hydrogen atoms, specifically, Methyl hydrazine, ethyl hydrazine, n-propyl hydrazine, i-propyl hydrazine, n-butyl hydrazine, i-butyl hydrazine, sec-butyl hydrazine, t-butyl hydrazine, n-pentyl hydrazine, i-pentyl hydrazine, neo-pentyl hydrazine T-pentylhydrazine, n-hexylhydrazine, i-hexylhydrazine, n-heptylhydrazine, n-octylhydrazine, n-nonylhydrazine, n-decylhydrazine, n-undecylhydrazine, n-dodecylhydrazine, cyclohexylhydrazine, F Sulfonyl hydrazine, 4-methylphenyl hydrazine, benzyl hydrazine, 2-phenylethyl hydrazine, and the like.

Further, for example, specific examples of the hydrazine derivative in which the substituent R ₁ is a methyl group and R ₃ and R ₄ are hydrogen atoms include 1,1-dimethylhydrazine, 1-methyl-1-ethylhydrazine, 1- Methyl-1-n-propylhydrazine, 1-methyl-1-i-propylhydrazine, 1-methyl-1-n-butylhydrazine, 1-methyl-1-i-butylhydrazine, 1-methyl-1-sec- Butyl hydrazine, 1-methyl-1-t-butyl hydrazine, 1-methyl-1-n-pentyl hydrazine, 1-methyl-1-i-pentyl hydrazine, 1-methyl-1-neo-pentyl hydrazine, 1-methyl -1-t-pentylhydrazine, 1-methyl-1-n-hexylhydrazine, 1-methyl-1-i-hexylhydrazine, 1-methyl-1-n-he Butyl hydrazine, 1-methyl-1-n-octyl hydrazine, 1-methyl-1-n-nonyl hydrazine, 1-methyl-1-n-decyl hydrazine, 1-methyl-1-n-undecyl hydrazine, 1- Methyl-1-n-dodecylhydrazine, 1-methyl-1-cyclohexylhydrazine, 1-methyl-1-phenylhydrazine, 1-methyl-1- (4-methyl) phenylhydrazine, 1-methyl-1-benzylhydrazine, Examples include 1-methyl-1- (2-phenyl) ethylhydrazine.

Also, for example, specific examples of the hydrazine derivative in which the substituent R ₁ is an ethyl group and R ₃ and R ₄ are hydrogen atoms include 1,1-diethylhydrazine, 1-ethyl-1-n-propylhydrazine, 1-ethyl-1-i-propyl hydrazine, 1-ethyl-1-n-butyl hydrazine, 1-ethyl-1-i-butyl hydrazine, 1-ethyl-1-sec-butyl hydrazine, 1-ethyl-1- t-butylhydrazine, 1-ethyl-1-n-pentylhydrazine, 1-ethyl-1-i-pentylhydrazine, 1-ethyl-1-neo-pentylhydrazine, 1-ethyl-1-t-pentylhydrazine, 1 -Ethyl-1-n-hexylhydrazine, 1-ethyl-1-i-hexylhydrazine, 1-ethyl-1-n-heptylhydrazine, 1-ethyl-1- n-octylhydrazine, 1-ethyl-1-n-nonylhydrazine, 1-ethyl-1-n-decylhydrazine, 1-ethyl-1-n-undecylhydrazine, 1-ethyl-1-n-dodecylhydrazine, 1-ethyl-1-cyclohexylhydrazine, 1-ethyl-1-phenylhydrazine, 1-ethyl-1- (4-methyl) phenylhydrazine, 1-ethyl-1-benzylhydrazine, 1-ethyl-1- (2- Examples include phenyl) ethylhydrazine and the like.

Further, for example, specific examples of the hydrazine derivative in which the substituent R ₁ is an n-propyl group and R ₃ and R ₄ are hydrogen atoms include 1,1-di-n-propyl hydrazine and 1-n-propyl. -1-i-propyl hydrazine, 1-n-propyl-1-n-butyl hydrazine, 1-n-propyl-1-i-butyl hydrazine, 1-n-propyl-1-sec-butyl hydrazine, 1-n -Propyl-1-t-butylhydrazine, 1-n-propyl-1-n-pentylhydrazine, 1-n-propyl-1-i-pentylhydrazine, 1-n-propyl-1-neo-pentylhydrazine, 1 -N-propyl-1-t-pentylhydrazine, 1-n-propyl-1-n-hexylhydrazine, 1-n-propyl-1-i-hexylhydrazine, 1-n-propyl -1-n-heptylhydrazine, 1-n-propyl-1-n-octylhydrazine, 1-n-propyl-1-n-nonylhydrazine, 1-n-propyl-1-n-decylhydrazine, 1-n -Propyl-1-n-undecylhydrazine, 1-n-propyl-1-n-dodecylhydrazine, 1-n-propyl-1-cyclohexylhydrazine, 1-n-propyl-1-phenylhydrazine, 1-n- Examples include propyl-1- (4-methyl) phenylhydrazine, 1-n-propyl-1-benzylhydrazine, 1-n-propyl-1- (2-phenyl) ethylhydrazine and the like.

Further, for example, specific examples of hydrazine derivatives in which the substituent R ₁ is an i-propyl group and R ₃ and R ₄ are hydrogen atoms include 1,1-di-i-propylhydrazine and 1-i-propyl. -1-n-butylhydrazine, 1-i-propyl-1-i-butylhydrazine, 1-i-propyl-1-sec-butylhydrazine, 1-i-propyl-1-t-butylhydrazine, 1-i -Propyl-1-n-pentylhydrazine, 1-i-propyl-1-i-pentylhydrazine, 1-i-propyl-1-neo-pentylhydrazine, 1-i-propyl-1-t-pentylhydrazine, 1 -I-propyl-1-n-hexylhydrazine, 1-i-propyl-1-i-hexylhydrazine, 1-i-propyl-1-n-heptylhydrazine, 1-i-propyl -1-n-octylhydrazine, 1-i-propyl-1-n-nonylhydrazine, 1-i-propyl-1-n-decylhydrazine, 1-i-propyl-1-n-undecylhydrazine, 1- i-propyl-1-n-dodecylhydrazine, 1-i-propyl-1-cyclohexylhydrazine, 1-i-propyl-1-phenylhydrazine, 1-i-propyl-1- (4-methyl) phenylhydrazine, 1 Examples include -i-propyl-1-benzylhydrazine, 1-i-propyl-1- (2-phenyl) ethylhydrazine and the like.

Further, for example, specific examples of the hydrazine derivative in which the substituent R ₁ is an n-butyl group and R ₃ and R ₄ are hydrogen atoms include 1,1-di-n-butylhydrazine and 1-n-butyl. -1-i-butylhydrazine, 1-n-butyl-1-sec-butylhydrazine, 1-n-butyl-1-t-butylhydrazine, 1-n-butyl-1-n-pentylhydrazine, 1-n -Butyl-1-i-pentylhydrazine, 1-n-butyl-1-neo-pentylhydrazine, 1-n-butyl-1-t-pentylhydrazine, 1-n-butyl-1-n-hexylhydrazine, 1 -N-butyl-1-i-hexylhydrazine, 1-n-butyl-1-n-heptylhydrazine, 1-n-butyl-1-n-octylhydrazine, 1-n-butyl-1-n-nonylhydrazine 1-n-butyl-1-n-decylhydrazine, 1-n-butyl-1-n-undecylhydrazine, 1-n-butyl-1-n-dodecylhydrazine, 1-n-butyl-1-cyclohexyl Hydrazine, 1-n-butyl-1-phenylhydrazine, 1-n-butyl-1- (4-methyl) phenylhydrazine, 1-n-butyl-1-benzylhydrazine, 1-n-butyl-1- (2 -Phenyl) ethylhydrazine and the like are exemplified.

In addition, specific examples of the hydrazine derivative in which the substituent R ₁ is an i-butyl group and R ₃ and R ₄ are hydrogen atoms include 1,1-di-i-butylhydrazine and 1-i-butyl. -1-sec-butylhydrazine, 1-i-butyl-1-t-butylhydrazine, 1-i-butyl-1-n-pentylhydrazine, 1-i-butyl-1-i-pentylhydrazine, 1-i -Butyl-1-neo-pentylhydrazine, 1-i-butyl-1-t-pentylhydrazine, 1-i-butyl-1-n-hexylhydrazine, 1-i-butyl-1-i-hexylhydrazine, 1 -I-butyl-1-n-heptylhydrazine, 1-i-butyl-1-n-octylhydrazine, 1-i-butyl-1-n-nonylhydrazine, 1-i-butyl-1-n-decylhydrazine 1-i-butyl-1-n-undecylhydrazine, 1-i-butyl-1-n-dodecylhydrazine, 1-i-butyl-1-cyclohexylhydrazine, 1-i-butyl-1-phenylhydrazine, Examples include 1-i-butyl-1- (4-methyl) phenylhydrazine, 1-i-butyl-1-benzylhydrazine, 1-i-butyl-1- (2-phenyl) ethylhydrazine and the like.

Further, for example, specific examples of the hydrazine derivative in which the substituent R ₁ is a sec-butyl group and R ₃ and R ₄ are hydrogen atoms include 1,1-di-sec-butylhydrazine and 1-sec-butyl. -1-t-butylhydrazine, 1-sec-butyl-1-n-pentylhydrazine, 1-sec-butyl-1-i-pentylhydrazine, 1-sec-butyl-1-neo-pentylhydrazine, 1-sec -Butyl-1-t-pentylhydrazine, 1-sec-butyl-1-n-hexylhydrazine, 1-sec-butyl-1-i-hexylhydrazine, 1-sec-butyl-1-n-heptylhydrazine, 1 -Sec-butyl-1-n-octylhydrazine, 1-sec-butyl-1-n-nonylhydrazine, 1-sec-butyl-1-n-decylhydride Razine, 1-sec-butyl-1-n-undecylhydrazine, 1-sec-butyl-1-n-dodecylhydrazine, 1-sec-butyl-1-cyclohexylhydrazine, 1-sec-butyl-1-phenylhydrazine 1-sec-butyl-1- (4-methyl) phenylhydrazine, 1-sec-butyl-1-benzylhydrazine, 1-sec-butyl-1- (2-phenyl) ethylhydrazine and the like.

Further, for example, specific examples of hydrazine derivatives in which the substituent R ₁ is a t-butyl group and R ₃ and R ₄ are hydrogen atoms include 1,1-di-t-butylhydrazine and 1-t-butyl. -1-n-pentylhydrazine, 1-t-butyl-1-i-pentylhydrazine, 1-t-butyl-1-neo-pentylhydrazine, 1-t-butyl-1-t-pentylhydrazine, 1-t -Butyl-1-n-hexylhydrazine, 1-t-butyl-1-i-hexylhydrazine, 1-t-butyl-1-n-heptylhydrazine, 1-t-butyl-1-n-octylhydrazine, 1 -T-butyl-1-n-nonylhydrazine, 1-t-butyl-1-n-decylhydrazine, 1-t-butyl-1-n-undecylhydrazine, 1-t-butyl-1-n-dodecyl Hydraj 1-t-butyl-1-cyclohexylhydrazine, 1-t-butyl-1-phenylhydrazine, 1-t-butyl-1- (4-methyl) phenylhydrazine, 1-t-butyl-1-benzylhydrazine 1-t-butyl-1- (2-phenyl) ethylhydrazine and the like.

Further, for example, specific examples of hydrazine derivatives in which the substituent R ₁ is an n-pentyl group and R ₃ and R ₄ are hydrogen atoms include 1,1-di-n-pentylhydrazine and 1-n-pentyl. -1-i-pentylhydrazine, 1-n-pentyl-1-neo-pentylhydrazine, 1-n-pentyl-1-t-pentylhydrazine, 1-n-pentyl-1-n-hexylhydrazine, 1-n -Pentyl-1-i-hexylhydrazine, 1-n-pentyl-1-n-heptylhydrazine, 1-n-pentyl-1-n-octylhydrazine, 1-n-pentyl-1-n-nonylhydrazine, 1 -N-pentyl-1-n-decylhydrazine, 1-n-pentyl-1-n-undecylhydrazine, 1-n-pentyl-1-n-dodecylhydrazine, 1-n-penty 1-cyclohexyl hydrazine, 1-n-pentyl-1-phenylhydrazine, 1-n-pentyl-1- (4-methyl) phenylhydrazine, 1-n-pentyl-1-benzylhydrazine, 1-n-pentyl Examples include -1- (2-phenyl) ethylhydrazine.

Further, for example, specific examples of the hydrazine derivative in which the substituent R ₁ is an i-pentyl group and R ₃ and R ₄ are hydrogen atoms include 1,1-di-i-pentylhydrazine and 1-i-pentyl. -1-neo-pentylhydrazine, 1-i-pentyl-1-t-pentylhydrazine, 1-i-pentyl-1-n-hexylhydrazine, 1-i-pentyl-1-i-hexylhydrazine, 1-i -Pentyl-1-n-heptylhydrazine, 1-i-pentyl-1-n-octylhydrazine, 1-i-pentyl-1-n-nonylhydrazine, 1-i-pentyl-1-n-decylhydrazine, 1 -I-pentyl-1-n-undecylhydrazine, 1-i-pentyl-1-n-dodecylhydrazine, 1-i-pentyl-1-cyclohexylhydrazine, 1-i-pen Til-1-phenylhydrazine, 1-i-pentyl-1- (4-methyl) phenylhydrazine, 1-i-pentyl-1-benzylhydrazine, 1-i-pentyl-1- (2-phenyl) ethylhydrazine, etc. Is exemplified.

Further, for example, as a hydrazine derivative in which the substituent R ₁ is a neo-pentyl group and R ₃ and R ₄ are hydrogen atoms, specifically, 1,1-di-neo-pentylhydrazine, 1-neo-pentyl -1-t-pentylhydrazine, 1-neo-pentyl-1-n-hexylhydrazine, 1-neo-pentyl-1-i-hexylhydrazine, 1-neo-pentyl-1-n-heptylhydrazine, 1-neo -Pentyl-1-n-octylhydrazine, 1-neo-pentyl-1-n-nonylhydrazine, 1-neo-pentyl-1-n-decylhydrazine, 1-neo-pentyl-1-n-undecylhydrazine, 1-neo-pentyl-1-n-dodecylhydrazine, 1-neo-pentyl-1-cyclohexylhydrazine, 1-neo-pe Nthyl-1-phenylhydrazine, 1-neo-pentyl-1- (4-methyl) phenylhydrazine, 1-neo-pentyl-1-benzylhydrazine, 1-neo-pentyl-1- (2-phenyl) ethylhydrazine, etc. Is exemplified.

Further, for example, specific examples of hydrazine derivatives in which the substituent R ₁ is a t-pentyl group and R ₃ and R ₄ are hydrogen atoms include 1,1-di-t-pentylhydrazine and 1-t-pentyl. -1-n-hexylhydrazine, 1-t-pentyl-1-i-hexylhydrazine, 1-t-pentyl-1-n-heptylhydrazine, 1-t-pentyl-1-n-octylhydrazine, 1-t -Pentyl-1-n-nonylhydrazine, 1-t-pentyl-1-n-decylhydrazine, 1-t-pentyl-1-n-undecylhydrazine, 1-t-pentyl-1-n-dodecylhydrazine, 1-t-pentyl-1-cyclohexylhydrazine, 1-t-pentyl-1-phenylhydrazine, 1-t-pentyl-1- (4-methyl) phenylhydrazine, 1-t-pe Examples thereof include nyl-1-benzylhydrazine and 1-t-pentyl-1- (2-phenyl) ethylhydrazine.

Further, for example, as a hydrazine derivative in which the substituent R ₁ is an n-hexyl group and R ₃ and R ₄ are hydrogen atoms, specifically, 1,1-di-n-hexylhydrazine, 1-n-hexyl -1-i-hexylhydrazine, 1-n-hexyl-1-n-heptylhydrazine, 1-n-hexyl-1-n-octylhydrazine, 1-n-hexyl-1-n-nonylhydrazine, 1-n -Hexyl-1-n-decylhydrazine, 1-n-hexyl-1-n-undecylhydrazine, 1-n-hexyl-1-n-dodecylhydrazine, 1-n-hexyl-1-cyclohexylhydrazine, 1- n-hexyl-1-phenylhydrazine, 1-n-hexyl-1- (4-methyl) phenylhydrazine, 1-n-hexyl-1-benzylhydrazine, 1-n-hexyl R-1- (2-phenyl) ethylhydrazine and the like are exemplified.

Further, for example, as hydrazine derivatives in which the substituent R ₁ is an i-hexyl group and R ₃ and R ₄ are hydrogen atoms, specifically, 1,1-di-i-hexylhydrazine, 1-i-hexyl -1-n-heptylhydrazine, 1-i-hexyl-1-n-octylhydrazine, 1-i-hexyl-1-n-nonylhydrazine, 1-i-hexyl-1-n-decylhydrazine, 1-i -Hexyl-1-n-undecylhydrazine, 1-i-hexyl-1-n-dodecylhydrazine, 1-i-hexyl-1-cyclohexylhydrazine, 1-i-hexyl-1-phenylhydrazine, 1-i- Examples include hexyl-1- (4-methyl) phenylhydrazine, 1-i-hexyl-1-benzylhydrazine, 1-i-hexyl-1- (2-phenyl) ethylhydrazine and the like. Indicated.

Further, for example, specific examples of the hydrazine derivative in which the substituent R ₁ is an n-heptyl group and R ₃ and R ₄ are hydrogen atoms include 1,1-di-n-heptylhydrazine and 1-n-heptyl. -1-n-octylhydrazine, 1-n-heptyl-1-n-nonylhydrazine, 1-n-heptyl-1-n-decylhydrazine, 1-n-heptyl-1-n-undecylhydrazine, 1- n-heptyl-1-n-dodecylhydrazine, 1-n-heptyl-1-cyclohexylhydrazine, 1-n-heptyl-1-phenylhydrazine, 1-n-heptyl-1- (4-methyl) phenylhydrazine, 1 Examples include -n-heptyl-1-benzylhydrazine, 1-n-heptyl-1- (2-phenyl) ethylhydrazine and the like.

Further, for example, specific examples of the hydrazine derivative in which the substituent R ₁ is an n-octyl group and R ₃ and R ₄ are hydrogen atoms include 1,1-di-n-octylhydrazine and 1-n-octyl. -1-n-nonylhydrazine, 1-n-octyl-1-n-decylhydrazine, 1-n-octyl-1-n-undecylhydrazine, 1-n-octyl-1-n-dodecylhydrazine, 1- n-octyl-1-cyclohexylhydrazine, 1-n-octyl-1-phenylhydrazine, 1-n-octyl-1- (4-methyl) phenylhydrazine, 1-n-octyl-1-benzylhydrazine, 1-n -Octyl-1- (2-phenyl) ethylhydrazine and the like are exemplified.

Further, for example, specific examples of the hydrazine derivative in which the substituent R ₁ is an n-nonyl group and R ₃ and R ₄ are hydrogen atoms include 1,1-di-n-nonylhydrazine and 1-n-nonyl. -1-n-decylhydrazine, 1-n-nonyl-1-n-undecylhydrazine, 1-n-nonyl-1-n-dodecylhydrazine, 1-n-nonyl-1-cyclohexylhydrazine, 1-n- Nonyl-1-phenylhydrazine, 1-n-nonyl-1- (4-methyl) phenylhydrazine, 1-n-nonyl-1-benzylhydrazine, 1-n-nonyl-1- (2-phenyl) ethylhydrazine, etc. Is exemplified.

Further, for example, specific examples of the hydrazine derivative in which the substituent R ₁ is an n-decyl group and R ₃ and R ₄ are hydrogen atoms include 1,1-di-n-decylhydrazine and 1-n-decyl. -1-n-undecylhydrazine, 1-n-decyl-1-n-dodecylhydrazine, 1-n-decyl-1-cyclohexylhydrazine, 1-n-decyl-1-phenylhydrazine, 1-n-decyl- Examples include 1- (4-methyl) phenylhydrazine, 1-n-decyl-1-benzylhydrazine, 1-n-decyl-1- (2-phenyl) ethylhydrazine and the like.

For example, specific examples of the hydrazine derivative in which the substituent R ₁ is an n-undecyl group and R ₃ and R ₄ are hydrogen atoms include 1,1-di-n-undecylhydrazine, 1-n- Undecyl-1-n-dodecylhydrazine, 1-n-undecyl-1-cyclohexylhydrazine, 1-n-undecyl-1-phenylhydrazine, 1-n-undecyl-1- (4-methyl) phenylhydrazine, 1-n -Undecyl-1-benzylhydrazine, 1-n-undecyl-1- (2-phenyl) ethylhydrazine and the like are exemplified.

Further, for example, as a hydrazine derivative in which the substituent R ₁ is an n-dodecyl group and R ₃ and R ₄ are hydrogen atoms, specifically, 1,1-di-n-dodecylhydrazine, 1-n-dodecyl -1-cyclohexylhydrazine, 1-n-dodecyl-1-phenylhydrazine, 1-n-dodecyl-1- (4-methyl) phenylhydrazine, 1-n-dodecyl-1-benzylhydrazine, 1-n-dodecyl- Examples include 1- (2-phenyl) ethylhydrazine.

Further, for example, specific examples of the hydrazine derivative in which the substituent R ₁ is a cyclohexyl group, and R ₃ and R ₄ are hydrogen atoms include 1,1-dicyclohexylhydrazine, 1-cyclohexyl-1-phenylhydrazine, 1- Examples include cyclohexyl-1- (4-methyl) phenylhydrazine, 1-cyclohexyl-1-benzylhydrazine, 1-cyclohexyl-1- (2-phenyl) ethylhydrazine and the like.

For example, specific examples of the hydrazine derivative in which the substituent R ₁ is a phenyl group and R ₃ and R ₄ are hydrogen atoms include 1,1-diphenylhydrazine and 1-phenyl-1- (4-methyl). Examples include phenylhydrazine, 1-phenyl-1-benzylhydrazine, 1-phenyl-1- (2-phenyl) ethylhydrazine and the like.

Further, for example, as a hydrazine derivative in which the substituent R ₁ is a 4-methylphenyl group and R ₃ and R ₄ are hydrogen atoms, specifically, 1,1-bis (4-methyl) phenylhydrazine, 1- Examples include (4-methyl) phenyl-1-benzylhydrazine, 1- (4-methyl) phenyl-1- (2-phenyl) ethylhydrazine and the like.

Further, for example, specific examples of hydrazine derivatives in which the substituent R ₁ is a benzyl group and R ₃ and R ₄ are hydrogen atoms include 1,1-dibenzylhydrazine and 1-benzyl-1- (2-phenyl). ) Ethyl hydrazine and the like are exemplified.

For example, specific examples of the hydrazine derivative in which the substituent R ₁ is a 2-phenylethyl group and R ₃ and R ₄ are hydrogen atoms include 1,1-bis (2-phenyl) ethylhydrazine and the like. Is done.

Among these hydrazine derivatives, those in which the carbon number of each of the substituents R _{1 to} R ₄ does not exceed 12 in the general formula (1) are preferable. When the carbon number of each of R _{1 to} R ₄ exceeds 12, the reducing power is reduced, or the boiling point of the hydrocarbons that are decomposition products at the time of preparing the copper fine particle dispersion is increased, and it is evaporated and diffused. In the case of using as a conductive pattern forming composition, the purity as metallic copper and the conductivity of the formed copper thin film may be adversely affected. . In view of reducing power, cost and safety, hydrazine derivatives include n-propyl hydrazine, i-propyl hydrazine, n-butyl hydrazine, t-butyl hydrazine, n-pentyl hydrazine, n-hexyl hydrazine, n-heptyl hydrazine. N-octylhydrazine, n-nonylhydrazine, n-decylhydrazine, n-undecylhydrazine, n-dodecylhydrazine, cyclohexylhydrazine, phenylhydrazine, benzylhydrazine, 1,1-dimethylhydrazine and 1,1-diethylhydrazine It is more preferable to use one kind selected from the group consisting of two or more kinds in combination.

  The copper fine particle dispersion of the present invention may contain a hydrazine derivative other than those described above as long as it does not contradict the spirit of the present invention.

  The hydrazine derivative represented by the above general formula (1) may be a commercially available product or may be synthesized by a known method, and is not particularly limited. Known preparation methods include, for example, a method of reducing an aromatic diazonium salt with a reducing agent such as sulfite or tin (II) chloride, a method of catalytic reduction of hydrazone or azine using a platinum catalyst, reduction of acylhydrazine, Examples include reduction of N-nitrosamines, reductive coupling of highly succeeding nitro compounds, alkylation and arylation of hydrazine and azine, reaction of amine and chloramine (Reaching reaction), and the like. Further, the purity of the hydrazine derivative represented by the general formula (1) is not particularly limited, but is preferably 95% or more, and more preferably 99% or more in consideration of use in the field of electronic materials.

  In the copper fine particle dispersion of the present invention, the contained copper fine particles have an average particle diameter in the range of 1 to 1000 nm. When the particle diameter of the copper fine particles is less than 1 nm, the activity on the copper surface is increased and the oxidation may not be suppressed. Moreover, when the use as a composition for electroconductive pattern formation is considered, the average particle diameter of a copper fine particle has the preferable range of 1-400 nm. By setting the particle diameter of the copper fine particles to 400 nm or less, it is possible to suppress a decrease in dispersibility, such as precipitation of copper fine particles or precipitation when stored for a long period of time.

In the present invention, a general particle measuring method can be used as a method for measuring the particle diameter of the copper fine particles. For example, a transmission electron microscope (TEM), a field emission transmission electron microscope (FE-TEM), a field emission scanning electron microscope (FE-SEM), or the like can be used as appropriate. The average particle size value is, for example,
(1) Measure using the above apparatus, and select three locations where the particle diameters are relatively uniform from the observed field of view.
(2) Take a photograph at the most suitable magnification for particle size measurement, select 100 copper fine particles that are most likely to exist from each photograph, measure their diameter with a ruler, and divide the measurement magnification, Calculate the particle size of each copper fine particle,
(3) arithmetically average these values,
Can be obtained. The standard deviation can be obtained from the particle size and number of individual copper fine particles during the observation. The coefficient of variation can be calculated by the following equation based on the above average particle diameter and its standard deviation.

  Coefficient of variation = standard deviation / volume average particle diameter × 100 (%).

  In the copper fine particle dispersion of the present invention, the composition ratio of the hydrazine derivative and the copper fine particle is not particularly limited, but the hydrazine derivative is preferably 5 to 10,000% by weight with respect to the amount of copper fine particles, and 50 to 1000% by weight. % Is more preferable. If the amount of the hydrazine derivative is less than 5% by weight relative to the amount of copper fine particles, the oxidation may not be suppressed. Even if the amount exceeds 10000% by weight, not only the improvement effect is obtained, but also copper is not obtained. This is not preferable because the content of metallic copper per unit weight in the fine particle dispersion is lowered.

  In the copper fine particle dispersion of the present invention, the hydrazine derivative represented by the general formula (1) and the copper fine particles having an average particle size in the range of 1 to 1000 nm are not particularly problematic, but in addition, the hydrazine derivative Any organic solvent can be used as long as it dissolves and does not react with the hydrazine derivative. Examples of such an organic solvent include one kind selected from the group consisting of alcohols, glycols, ethers, esters, hydrocarbons, and aromatic hydrocarbons, or a mixture of two or more kinds having compatibility. Is mentioned.

  Specifically, as alcohols, methanol, ethanol, n-propyl alcohol, i-propyl alcohol, n-butyl alcohol, i-butyl alcohol, sec-butyl alcohol, pentanol, hexanol, heptanol, octanol, cyclohexanol , Benzyl alcohol, terpineol, and the like. Specific examples of glycols include ethylene glycol, propylene glycol, butylene glycol, pentanediol, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol, and the like. Specific examples of ethers include diethylene glycol dimethyl ether, diethylene glycol diethyl ether, and triethylene glycol dimethyl ether. , Triethylene glycol diethyl ether, tetrahydrofuran, tetrahydropyran, 1,4-dioxane, and the like. Specific examples of the esters include methyl formate, ethyl formate, butyl formate, methyl acetate, ethyl acetate, butyl acetate, Examples thereof include methyl propionate, ethyl propionate, butyl propionate, and γ-butyrolactone. Specific examples of hydrocarbons include n-pentane, n-hexane, n-heptane, n-octane, and n-nonane. , N-decane, n-undecane, n-dodecane, cyclohexane, decalin and the like. Specific examples of aromatic hydrocarbons include benzene, toluene, xylene, ethylbenzene, n-propylbenzene, i-propyl. Benzene, n-butylbenzene, mesitylene, chlorobenzene, Examples include dichlorobenzene.

  Among them, from the viewpoint of cost and safety, one selected from the group consisting of ethanol, i-propyl alcohol, terpineol, ethylene glycol, propylene glycol, diethylene glycol dimethyl ether, γ-butyrolactone, n-decane, toluene and n-butylbenzene, or It is more preferable to use a combination of two or more compatible types.

  In the copper fine particle dispersion of the present invention, when the composition includes an organic solvent, the total amount of the hydrazine derivative and the copper fine particle is 0.1 wt% or more and less than 100 wt% with respect to the total weight of the copper fine particle dispersion. The balance is preferably an organic solvent, more preferably 10 wt% or more and 80 wt% or less, and the balance is more preferably an organic solvent. When the total amount of the hydrazine derivative and the copper fine particles is less than 10% by weight with respect to the total weight of the copper fine particle dispersion, an operation such as concentration is required when using the composition as a conductive pattern forming composition. If it exceeds 80% by weight, the fluidity is lowered and the workability may be significantly lowered.

  The form of the copper fine particle dispersion of the present invention can be freely selected as necessary. For example, it can be used as a concentrated liquid having a desired concentration by removing a part of the hydrazine derivative and / or organic solvent in the copper fine particle dispersion, or can be processed into a paste. Furthermore, since the concentrate or paste-like processed product can be redispersed in the presence of the organic solvent as described above, the organic solvent can be freely replaced.

  The copper fine particle dispersion of the present invention can be produced by bringing a hydrazine derivative and copper fine particles into contact with each other. As a known preparation method, for example, a method in which a hydrazine derivative is added to and mixed with copper fine particles dispersed in a liquid layer, or a vaporized hydrazine derivative is brought into contact with a copper fine particle powder. However, since the copper fine particles are immediately oxidized in the air atmosphere, the above method requires a complicated and expensive manufacturing apparatus, and enormous costs are required, which is not industrially advantageous. Therefore, a method of contacting the hydrazine derivative at the same time when the copper fine particles are synthesized is preferable.

  In the method for producing a copper fine particle dispersion according to the present invention, the method for synthesizing copper fine particles is not particularly limited, and any known method can be used. In order to avoid this, it is preferable to mix copper ions and a hydrazine derivative and to heat, and to utilize the reducing action of the hydrazine derivative to precipitate copper fine particles. According to this method, the production of copper fine particles and the contact between the copper fine particles and the hydrazine derivative can be carried out simultaneously and in the same reaction vessel, which is industrially advantageous.

  The method for producing a copper fine particle dispersion of the present invention includes the following two steps.

a) A step of mixing a hydrazine derivative and a copper fine particle precursor (hereinafter referred to as a step).
b) A step of reducing and precipitating copper fine particles by adding water to the mixture obtained in step a and heating it (hereinafter referred to as step b).
In the method for producing a copper fine particle dispersion of the present invention, it is only necessary to carry out the step a and the step b, and there may be no problem even if other steps are added. For example, a step of diluting a hydrazine derivative and / or a copper fine particle precursor, a step of diluting or concentrating a mixture of the hydrazine derivative and the copper fine particle precursor, a step of cooling or heating the mixture of the hydrazine derivative and the copper fine particle precursor, a copper fine particle A step of washing the dispersion, a step of diluting or concentrating the copper fine particle dispersion, a step of aggregating and / or precipitating the copper fine particles in the copper fine particle dispersion, and the like can be appropriately performed.

  In the method for producing a copper fine particle dispersion of the present invention, the copper fine particle precursor used in step a is not particularly limited as long as it is a compound containing copper ions, and specifically, cuprous oxide. , Copper oxides such as copper oxide, copper hydroxides such as copper hydroxide (I) and copper hydroxide (II), copper halides such as copper fluoride, copper chloride, copper bromide and copper iodide, bases Copper carbonate, copper nitrite, copper nitrate, copper sulfite, copper sulfate, copper phosphate, copper pyrophosphate and other copper inorganic acid salts, copper formate, copper acetate, copper propionate, copper butyrate, copper isobutyrate, valeric acid Copper, copper isovalerate, copper pivalate, copper oxalate, copper malonate, copper succinate, copper maleate, copper benzoate, copper citrate, copper tartrate, etc., copper acetylacetonate, ethylenediamine A copper chelate complex such as copper can be suitably used. Among these, copper acetate is particularly preferable from the viewpoint of cost. Although copper fine particle precursors other than those described above may be used, they may be industrially disadvantageous because they are difficult to obtain or expensive. Moreover, as a copper fine particle precursor, although the high purity thing marketed for electronic materials can be used, you may use what is distribute | circulated industrially.

  In the method for producing a copper fine particle dispersion of the present invention, as the hydrazine derivative used in step a, for example, a hydrazine derivative represented by the above general formula (1) is used.

  In the method for producing a copper fine particle dispersion of the present invention, the mixing ratio of the hydrazine derivative and the copper fine particle precursor in step a is not particularly limited, but the hydrazine derivative is 0 with respect to 1 molar equivalent of the copper fine particle precursor. It is preferably in the range of 25 to 1000 molar equivalents, more preferably in the range of 1 to 100 molar equivalents. If the amount of hydrazine derivative is less than 0.25 molar equivalents relative to the amount of metallic copper, there is a risk that reduction to metallic copper may not proceed completely. Not only is the effect not obtained, but the content of metallic copper per unit weight of the copper fine particle dispersion is lowered, which is not preferable.

  In the method for producing a copper fine particle dispersion of the present invention, the water added in step b is ionic such as ion-exchanged water, pure water or ultrapure water in consideration of using the copper fine particle dispersion as an electronic material. What reduced the substance, the particle, etc. as much as possible is preferable.

  In the method for producing a copper fine particle dispersion of the present invention, the amount of water added in step b depends on the amount of water brought in from the hydrated state of the copper fine particle precursor, and thus it is difficult to define, but dare to If it prescribes | regulates, what is necessary is just to add so that the amount of water brought in and the amount of added water derived from the hydration state of a copper fine particle precursor may become the range of 2-100 molar equivalent with respect to 1 molar equivalent of a copper fine particle precursor, It is more preferable to add so that it may become the range of 4-10 molar equivalent. When the amount of water brought from the hydration state of the copper fine particle precursor and the amount of added water are less than 2 molar equivalents relative to 1 molar equivalent of the copper fine particle precursor, the reduction to metallic copper does not proceed completely. There is a possibility, and even if it adds exceeding 100 molar equivalent, the improvement effect only added is not acquired.

  In the method for producing a copper fine particle dispersion of the present invention, the heating temperature in step b is not particularly limited as long as the hydrazine derivative can reduce copper ions to metallic copper, but is usually 0 to 300 ° C. The range of 50-200 degreeC is preferable. If it is less than 0 ° C., the reduction reaction may be extremely slow, and if it exceeds 300 ° C., the hydrazine derivative may decompose, which is not realistic.

  In the method for producing a copper fine particle dispersion of the present invention, in step b, pH adjustment may be performed in order to control the reduction reaction. Examples of the base for adjusting the pH include ammonia water, alkali metal hydroxides such as potassium hydroxide and sodium hydroxide, and quaternary ammonium salts such as tetramethylammonium hydroxide. Although these can use the highly purified thing marketed for electronic materials, you may use what is distribute | circulated industrially.

  In the method for producing a copper fine particle dispersion of the present invention, an organic solvent may be added in step a and / or step b. As such an organic solvent, the same organic solvent as described above that can be contained in the copper fine particle dispersion of the present invention can be used.

  In the method for producing a copper fine particle dispersion of the present invention, when an impurity inorganic component may be mixed, a reducing agent may be further added to the mixture of the copper fine particle precursor and the hydrazine derivative. The reducing agent is not particularly limited as long as it has a reducing power capable of reducing copper ions to metallic copper. Specifically, hydrazine, sodium hydrophosphate, tetrabutylammonium borohydride, lithium Preferred examples include borohydride, sodium borohydride, borane, diborane, formaldehyde, acetaldehyde, formic acid and the like. Among these, sodium borohydride is particularly preferable from the viewpoint of safety and cost. As the reducing agent, a high-purity one that is commercially available for electronic materials can be used, but those that are commercially available may also be used. The amount of the reducing agent used is not particularly limited as long as copper ions can be completely reduced to metallic copper, but is within a range of 1 to 10 molar equivalents relative to 1 molar equivalent of the copper fine particle precursor. It is preferable that it is in the range of 1 to 2 molar equivalents. If the amount of the reducing agent used is less than 1 molar equivalent relative to the number of moles of copper ions, the reduction to metallic copper may not proceed completely, and even if it exceeds 10 molar equivalents, the improvement effect only by use. Cannot be obtained.

  The copper fine particle dispersion of the present invention can be suitably used as an ink-like or paste-like conductive pattern forming composition as it is or by mixing an additive as necessary.

  Other uses of the copper fine particle dispersion of the present invention include materials such as electrode materials, catalysts, colorants, cosmetics, near infrared absorbers, optical recording materials, polarizing materials, anti-counterfeiting inks, and electromagnetic shielding materials. Etc.

  The copper fine particles of the present invention are copper fine particles having an average particle diameter in the range of 1 to 1000 nm, and are characterized in that the hydrazine derivative represented by the general formula (1) is adsorbed on the particle surface.

  The copper fine particles of the present invention are preferably those having an average particle diameter in the range of 1 to 400 nm in consideration of the use as a conductive pattern forming composition.

  The copper fine particles of the present invention can be obtained in the form of powder by separating the copper fine particles from the copper fine particle dispersion of the present invention by a separation operation.

  In the method for producing copper fine particles of the present invention, the operation for separating the copper fine particles is not particularly limited, and examples thereof include filtration, centrifugal separation, and distillation of components other than the copper fine particles.

  In the method for producing copper fine particles of the present invention, when the separation operation is filtration, a poor solvent can be added to promote aggregation of the copper fine particles in order to improve the filtration efficiency. As a poor solvent, the 1 type chosen from polar solvents, such as methanol, acetonitrile, and water, or 2 or more types of compatible mixtures can be used conveniently, for example.

  In the method for producing copper fine particles of the present invention, when the separation operation is centrifugation, a known method can be used.

  In the method for producing copper fine particles of the present invention, when the separation operation is distillation of components other than copper fine particles, a known method can be used, and the method is not particularly limited. When the temperature is higher than the decomposition temperature of the hydrazine derivative, it is preferably carried out under reduced pressure conditions.

  The copper fine particles of the present invention can be suitably used as an ink-like or paste-like conductive pattern forming composition by re-dispersing in an organic solvent and mixing additives as necessary.

  The conductive pattern forming composition of the present invention contains the above-described copper fine particle dispersion of the present invention, or contains the above-described copper fine particles of the present invention and a dispersant for dispersing the copper fine particles.

  In the composition for forming a conductive pattern of the present invention, the dispersant for dispersing the copper fine particles of the present invention is not particularly limited, but the surface of the copper fine particles of the present invention is represented by the general formula (1). Since the hydrazine derivative shown is adsorbed, its concentration, viscosity, etc. can be freely controlled by using an organic solvent as a dispersant.

  Although it does not specifically limit as an organic solvent, For example, it is 1 type chosen from the group which consists of alcohols, glycols, ethers, ester, hydrocarbons, and aromatic hydrocarbons, or compatibility. The mixture of 2 or more types is mentioned.

  Specifically, as alcohols, methanol, ethanol, n-propyl alcohol, i-propyl alcohol, n-butyl alcohol, i-butyl alcohol, sec-butyl alcohol, pentanol, hexanol, heptanol, octanol, cyclohexanol , Benzyl alcohol, terpineol, and the like. Specific examples of glycols include ethylene glycol, propylene glycol, butylene glycol, pentanediol, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol, and the like. Specific examples of ethers include diethylene glycol dimethyl ether, diethylene glycol diethyl ether, and triethylene glycol dimethyl ether. , Triethylene glycol diethyl ether, tetrahydrofuran, tetrahydropyran, 1,4-dioxane, and the like. Specific examples of the esters include methyl formate, ethyl formate, butyl formate, methyl acetate, ethyl acetate, butyl acetate, Examples thereof include methyl propionate, ethyl propionate, butyl propionate, and γ-butyrolactone. Specific examples of hydrocarbons include n-pentane, n-hexane, n-heptane, n-octane, and n-nonane. , N-decane, n-undecane, n-dodecane, cyclohexane, decalin and the like. Specific examples of aromatic hydrocarbons include benzene, toluene, xylene, ethylbenzene, n-propylbenzene, i-propyl. Benzene, n-butylbenzene, mesitylene, chlorobenzene, Examples include dichlorobenzene.

  Among these, from the viewpoint of cost and safety, one kind selected from the group consisting of ethanol, i-propyl alcohol, terpineol, ethylene glycol, propylene glycol, diethylene glycol dimethyl ether, γ-butyrolactone, n-decane, toluene and n-butylbenzene. It is more preferable to use two or more compatible types in combination.

  In the conductive pattern forming composition containing the copper fine particles of the present invention and the dispersant for dispersing the copper fine particles, the amount of the copper fine particles is 0.1% by weight with respect to the weight of the copper fine particles and the entire dispersant. As mentioned above, it is preferable that it is less than 100 weight% and the remainder is an organic solvent, and it is more preferable that it is 10 weight% or more and 80 weight% or less, and the remainder is an organic solvent. If the total amount of the copper fine particles is less than 10% by weight with respect to the weight of the copper fine particles and the entire dispersant, the operation such as concentration is required at the time of use, which may increase the number of work steps, and exceeds 80% by weight. Then, the fluidity is lowered and the workability may be significantly lowered.

  The composition for forming an electroconductive pattern of the present invention can contain additives such as a viscosity modifier and a surface tension modifier as necessary.

  The conductive pattern forming composition of the present invention can be used for printed wiring by drawing and heating on a substrate by ink jet, dispenser or screen printing, and high density recording by applying and drying on a substrate. It can be used as a material or a light shielding filter.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not construed as being limited in any way by these examples.

  In the following examples, the average particle diameter of the copper fine particles was selected from three locations where the particle diameters were relatively uniform from the field of view observed with a transmission electron microscope (TEM), and 100,000. Take a photo at double magnification, select a total of 100 particles from each photo, measure the diameter with a ruler, calculate the particle size by dividing the measurement magnification, and obtain these values by arithmetic averaging It was. TEM used the product name "JEM-2000FX" made by JEOL.

Example 1 Preparation of a copper fine particle dispersion containing n-hexylhydrazine.
After adding 2 g of copper (II) acetate monohydrate to 20 g of n-hexylhydrazine and completely dissolving it, 2 g of water was added and the mixture was heated and stirred at 100 ° C. for 30 minutes to obtain a black copper fine particle dispersion. When this copper fine particle dispersion was observed with a TEM and the average particle size was determined, it was 34 nm (standard deviation 17.7, coefficient of variation 52%). Even if the obtained copper fine particle dispersion was left in the atmosphere for 1 hour, no discoloration due to oxidation was observed, and the uniform dispersion state was maintained. To the copper fine particle dispersion, 100 ml of acetonitrile: water = 1: 1 (v / v) solution was added and allowed to stand, and the resulting precipitate was filtered to obtain a copper fine particle powder. The obtained copper fine particle powder was redispersible in i-butyl alcohol.

Example 2 Preparation of a copper fine particle dispersion containing n-dodecylhydrazine.
20 g of n-dodecylhydrazine and 20 g of octanol were mixed, 2 g of copper (II) acetate monohydrate and 2 g of water were added, and the mixture was heated and stirred at 110 ° C. for 30 minutes to obtain a black copper fine particle dispersion. When this copper fine particle dispersion was observed with a TEM and the average particle size was determined, it was 54 nm (standard deviation 19.4, coefficient of variation 36%). Even if the obtained copper fine particle dispersion was left in the atmosphere for 1 hour, no discoloration due to oxidation was observed, and the uniform dispersion state was maintained. To the copper fine particle dispersion, 100 ml of acetonitrile: water = 1: 1 (v / v) solution was added and allowed to stand, and the resulting precipitate was filtered to obtain a copper fine particle powder. The obtained copper fine particle powder was redispersible in toluene.

Example 3 Preparation of a copper fine particle dispersion containing phenylhydrazine.
After adding 2 g of copper (II) acetate monohydrate to 20 g of phenylhydrazine and completely dissolving it, 2 g of water was added and the mixture was heated and stirred at 110 ° C. for 30 minutes to obtain a black copper fine particle dispersion. When this copper fine particle dispersion was observed with a TEM and the average particle size was determined, it was 68 nm (standard deviation 18.1, variation coefficient 27%). Even if the obtained copper fine particle dispersion was left in the atmosphere for 1 hour, no discoloration due to oxidation was observed, and the uniform dispersion state was maintained. To the copper fine particle dispersion, 100 ml of acetonitrile: water = 1: 1 (v / v) solution was added and allowed to stand, and the resulting precipitate was filtered to obtain a copper fine particle powder. The obtained copper fine particle powder was redispersible in diethylene glycol dimethyl ether.

Example 4 Preparation of a copper fine particle dispersion containing 1,1-dimethylhydrazine.
Mixing 20 g of 1,1-dimethylhydrazine and 20 g of 1,4-dioxane, adding 2 g of copper (II) oxalate.0.5 hydrate and 2 g of water, and heating and stirring at 70 ° C. for 30 minutes, A copper fine particle dispersion was obtained. When this copper fine particle dispersion was observed with a TEM and the average particle size was determined, it was 95 nm (standard deviation 20.9, variation coefficient 22%). Even if the obtained copper fine particle dispersion was left in the atmosphere for 1 hour, no discoloration due to oxidation was observed, and the uniform dispersion state was maintained. To the copper fine particle dispersion, 100 ml of acetonitrile: water = 1: 1 (v / v) solution was added and allowed to stand, and the resulting precipitate was filtered to obtain a copper fine particle powder. The obtained copper fine particle powder was redispersible in n-octane.

Comparative Example 1 Preparation of a copper fine particle dispersion containing hydrazine.
When 20 g of hydrazine monohydrate and 20 g of ethylene glycol were mixed, 2 g of copper (II) acetate monohydrate was added and stirred with heating at 50 ° C. for 30 minutes, a black copper fine particle dispersion was not obtained, and reddish brown copper particles A precipitate was formed. When this copper fine particle precipitate was observed with TEM and the average particle size was calculated, it was 1100 nm (standard deviation 28.5, variation coefficient 2.6%). The copper particle powder was obtained by filtering a copper particle precipitate. The obtained copper particle powder was redispersible in ethanol, but settled in about 1 hour.

Claims (12)

The following general formula (1)

[In General Formula (1), R _{1 to} R ₄ are each independently a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, an aromatic group having 5 to 10 carbon atoms, or an alkyl having 1 to 4 carbon atoms. Group having 5 to 10 carbon atoms substituted with 1 to 3 hydrogen atoms on the aromatic ring, or 1 to 4 carbon atoms having 1 to 3 hydrogen atoms substituted with an aromatic group having 5 to 10 carbon atoms Represents an alkyl group. However, R _{1 to} R ₄ are not all hydrogen atoms. ]
A copper fine particle dispersion containing a hydrazine derivative represented by the formula (1) and copper fine particles having an average particle diameter in the range of 1 to 1000 nm. In General Formula (1), R ₁ and R ₂ are each independently a hydrogen atom, a methyl group, an ethyl group, a linear, branched or cyclic alkyl group having 3 to 18 carbon atoms, 10 aromatic group, an aromatic group having 5 to 10 carbon atoms in which hydrogen on the aromatic ring is substituted by 1 to 3 by a methyl group, a methyl group in which hydrogen is substituted by 1 to 3 by a phenyl group, or hydrogen by a phenyl group 2. An ethyl group having 1 to 3 atoms substituted (provided that R ₁ and R ₂ are not hydrogen atoms at the same time), and R ₃ and R ₄ are hydrogen atoms. The copper fine particle dispersion described in 1. In the general formula (1), R ₁ and R ₂ are each independently a hydrogen atom, methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, sec-butyl. Group, t-butyl group, n-pentyl group, i-pentyl group, neo-pentyl group, t-pentyl group, n-hexyl group, i-hexyl group, n-heptyl group, n-octyl group, n-nonyl Represents a group, n-decyl group, n-undecyl group, n-dodecyl group, cyclohexyl group, phenyl group, 4-methylphenyl group, benzyl group, or 2-phenylethyl group (provided that R ₁ and R ₂ are simultaneously The copper fine particle dispersion according to claim 1 or 2, wherein R ₃ and R ₄ are hydrogen atoms. The copper fine particle dispersion according to any one of claims 1 to 3, wherein the copper fine particle contains a hydrazine derivative in an amount of 5 to 10,000% by weight. The manufacturing method of the copper fine particle dispersion in any one of Claims 1 thru | or 4 including the process of the following a) and b).
a) A step of mixing a hydrazine derivative represented by the general formula (1) and a copper fine particle precursor.
b) A step of reducing and precipitating copper fine particles by adding water to the mixture obtained in step a) and heating the mixture. The copper fine particle precursor is one or two or more compounds selected from the group consisting of copper oxide, copper hydroxide, copper halide, copper inorganic acid salt, copper organic acid salt and copper chelate complex. The method for producing a copper fine particle dispersion according to claim 5. Copper fine particle precursor is cuprous oxide, copper oxide, copper hydroxide, copper nitrate, basic copper carbonate, copper formate, copper acetate, copper propionate, copper butyrate, copper isobutyrate, copper valerate, copper isovalerate The copper according to claim 5, which is one or more selected from the group consisting of copper pivalate, copper oxalate, copper malonate, copper benzoate, copper citrate and copper acetylacetonate. A method for producing a fine particle dispersion. The composition for conductive pattern formation containing the copper fine particle dispersion in any one of Claims 1 thru | or 4. Copper fine particles having an average particle diameter in the range of 1 to 1000 nm, the following general formula (1)

[In General Formula (1), R _{1 to} R ₄ are each independently a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, an aromatic group having 5 to 10 carbon atoms, or an alkyl having 1 to 4 carbon atoms. Group having 5 to 10 carbon atoms substituted with 1 to 3 hydrogen atoms on the aromatic ring, or 1 to 4 carbon atoms having 1 to 3 hydrogen atoms substituted with an aromatic group having 5 to 10 carbon atoms Represents an alkyl group. However, R _{1 to} R ₄ are not all hydrogen atoms. ]
A copper fine particle, wherein the surface of the copper fine particle is coated with a hydrazine derivative represented by the formula: The method for producing copper fine particles according to claim 9, wherein the copper fine particles are separated from the copper fine particle dispersion according to any one of claims 1 to 4 by a separation operation. The method for producing copper fine particles according to claim 10, wherein the separation operation is filtration, centrifugation, or distillation of components other than the copper fine particles. The composition for electroconductive pattern formation containing the copper fine particle of Claim 9, and the dispersing agent which disperse | distributes a copper fine particle.