Top > Search of International Patents > COPPER PARTICLE MIXTURE AND METHOD FOR MANUFACTURING SAME, COPPER PARTICLE MIXTURE DISPERSION, INK CONTAINING COPPER PARTICLE MIXTURE, METHOD FOR STORING COPPER PARTICLE MIXTURE, AND METHOD FOR SINTERING COPPER PARTICLE MIXTURE

COPPER PARTICLE MIXTURE AND METHOD FOR MANUFACTURING SAME, COPPER PARTICLE MIXTURE DISPERSION, INK CONTAINING COPPER PARTICLE MIXTURE, METHOD FOR STORING COPPER PARTICLE MIXTURE, AND METHOD FOR SINTERING COPPER PARTICLE MIXTURE

Foreign code F190009691
File No. (S2017-0624-N0)
Posted date Jan 23, 2019
Country WIPO
International application number 2018JP014637
International publication number WO 2018190246
Date of international filing Apr 5, 2018
Date of international publication Oct 18, 2018
Priority data
  • P2017-080971 (Apr 14, 2017) JP
Title COPPER PARTICLE MIXTURE AND METHOD FOR MANUFACTURING SAME, COPPER PARTICLE MIXTURE DISPERSION, INK CONTAINING COPPER PARTICLE MIXTURE, METHOD FOR STORING COPPER PARTICLE MIXTURE, AND METHOD FOR SINTERING COPPER PARTICLE MIXTURE
Abstract The present invention provides a copper particle mixture and a method for manufacturing the same, a copper particle mixture dispersion in which the copper particle mixture is dispersed, and an ink containing the copper particle mixture, the ink containing the copper particle mixture dispersion, the copper particle mixture whereby oxidation of the copper is suppressed, and the copper particle mixture has high dispersibility and can be sintered at low temperature in a short time in a reducing atmosphere or a non-reducing atmosphere. The present invention is a copper particle mixture including copper fine particles A and copper nanoparticles B, the copper particle mixture being characterized in that the copper fine particles A have an average particle diameter of 0.1 µm to 5 µm and are coated by at least one species of dicarboxylic acid selected from the group consisting of malonic acid and oxalic acid, the copper nanoparticles B comprise a center part comprising a copper single crystal and a protective layer on the periphery of the center part, the average particle diameter of the copper nanoparticles B is 1 nm to less than 100 nm, and the protective layer of the copper nanoparticles B includes at least one species selected from the group consisting of a C3-6 primary alcohol, a C3-6 secondary alcohol, and a derivative thereof.
Outline of related art and contending technology BACKGROUND ART
The extent size is 2nm-100nm diameter of the nano-particles, optical properties, magnetic properties, thermal properties, electrical properties and the like, is different from the properties of the bulk metal from, a variety of techniques are expected to be applied to the art.For example, have a small particle size and increase surface area by using the characteristic that a decrease in melting point, metal nano-particles including fine wiring using the ink for printing, fine metal wires on the substrate to produce an electronic circuit has been studied.
In such a fine wiring pattern is printing ink, an organic material to protect the surface of the metal nanoparticle dispersion liquid containing the ink material, a fine wiring of a substrate using a printing technique on the printed circuit pattern, by the low temperature heating, the metal nano fine particles and organic substances removed from the surface of the metal bonding between the nano-particles occurs.In particular, the use of nano-particles of a diameter of 10nm or less, lowering the melting point of noticeable.Thus, thermal conductivity and high electric conductivity can be a metal to form a fine wiring.
As the metal wiring, is used in the bulk copper.The bulk copper, the oxide tends to decrease conductivity, has disadvantages that the firing temperature is high.On the other hand, the copper nanoparticles having a lower sintering temperature than copper Bulk, such as paper or plastic is weak against heat even on a substrate as a material for wiring can be formed in a metal microstructure has been expected.
However, copper nanoparticles, gold, silver or the like compared to other nano-particles are easily aggregated, the aggregation of several hundred nm - several tens nm in order to have a particle size, the ink is particularly useful as a material having an average particle diameter of 10nm or less of the copper nanoparticles dispersion of the synthesis is difficult.
Is weak to heat metal to a substrate such as paper or plastic fine wiring can be formed as nano-ink, a significant drop in the melting point of 10nm or less of copper nanoparticles having an average particle diameter is desired, a low temperature of 150°C or less copper nanoparticles which were sintered at a low temperature is difficult to obtain.This is, 10nm or less of copper nanoparticles having an average particle size, high reactivity and therefore unstable and, oxidation and agglomeration of the copper nanoparticles is easily occurs.Immediately after the copper nano-particles of copper nanoparticles is difficult to stably be stored.Therefore, the average particle diameter of copper nanoparticles is very small size of 10nm, the surface of the polymer strongly bonded to the copper and the like manufactured using a protective agent.However, the protective agent, a low temperature cannot be completely removed at the time of heating, the electric conductivity of the metal fine wires leading to a reduction in the problem.
In addition, the copper nanoparticles and the metal to form a fine wiring, fine wiring and ionization of the copper oxide, on the insulating substrate is moved to induce a short circuit, a problem that the so-called migration phenomenon.
As described above solves the problem that the printing ink as a material for fine wiring, and a center portion of a single crystal of copper, and a protective layer formed around the copper nanoparticles, (1) average particle diameter of 10nm or less, (2) the protective layer, having a carbon number of 3-6 1 primary alcohols, secondary alcohols having a carbon number of 3-6 2 is selected from 1 and derivatives thereof include at least one, (3) a thermal decomposition temperature or a boiling point of the protective layer is 150°C or less of the copper nanoparticles have been proposed (for example, see Patent Document 1).
Patent Document 1 may be of copper nanoparticles, copper oxidation, melting point, excellent in dispersibility, and sintered at a low temperature, and the protective layer at a low temperature of 150°C or less can be removed during sintering, the copper nanoparticles have a conductive ink material can be suitably used in the copper nanoparticles is excellent in, further lowering the sintering temperature of the studied there is room for improvement.For printing the ink material is fine wiring, the non-reducing atmosphere at a sintering at a low temperature of 120°C or less is required and possible, and, in a reducing atmosphere of the atmosphere in a non-low temperature less than 150°C, sintering in a short time is obtained.
Accordingly, and to suppress oxidation of copper, high dispersibility, and, in a reducing atmosphere or in a non-reducing atmosphere in a short time for low-temperature sintering is possible, as the conductive ink material can be preferably used a mixture of copper particles, copper particles are dispersed in the mixture of the copper particle dispersion liquid mixture, and the copper particle mixture containing a dispersion liquid containing a mixture of copper particles has been required the development of ink, the copper particle mixture can be stored stably in the development of the storage method is demanded.
Scope of claims (In Japanese)請求の範囲 [請求項1]
 銅微粒子A及び銅ナノ粒子Bを含む銅粒子混合物であって、
 前記銅微粒子Aは、平均粒子径が0.1μm以上5μm以下であり、マロン酸及びシュウ酸からなる群より選択される少なくとも1種のジカルボン酸により被覆されており、
 前記銅ナノ粒子Bは、銅の単結晶からなる中心部、及びその周囲の保護層からなり、前記銅ナノ粒子Bの平均粒子径が1nm以上100nm未満であり、
 前記銅ナノ粒子Bの保護層は、炭素数3~6の1級アルコール、炭素数3~6の2級アルコール及びそれらの誘導体からなる群より選択される少なくとも1種を含む、
ことを特徴とする銅粒子混合物。

[請求項2]
 前記銅ナノ粒子Bの粒度分布に基づく標準偏差が銅ナノ粒子Bの平均粒子径の20%以下である、請求項1に記載の銅粒子混合物。

[請求項3]
 前記銅ナノ粒子B中の前記保護層の質量比は、前記銅ナノ粒子Bの質量を100質量%として10~30質量%である、請求項1又は2に記載の銅粒子混合物。

[請求項4]
 前記炭素数3~6の1級アルコール、炭素数3~6の2級アルコール及びそれらの誘導体からなる群より選択される少なくとも1種は、下記式(1)又は(2)で示される基を有する、請求項1~3のいずれかに記載の銅粒子混合物。
[化1]

(式(1)及び(2)中、*は結合手を示す。)

[請求項5]
 前記銅微粒子Aの質量(Ma)と、前記銅ナノ粒子Bの質量(Mb)との合計(Ma+Mb)に対する前記銅ナノ粒子Bの質量(Mb)の割合が、2質量%以上である、請求項1~4のいずれかに記載の銅粒子混合物。

[請求項6]
 請求項1~5のいずれかに記載の銅粒子混合物が分散媒中に分散されている銅粒子混合物分散液。

[請求項7]
 請求項6に記載の銅粒子混合物分散液を含有する、銅粒子混合物含有インク。

[請求項8]
 請求項1~5のいずれかに記載の銅粒子混合物を、非還元性雰囲気中で、常圧又は減圧下で、120℃以下の温度で焼結させる、銅粒子混合物の焼結方法。

[請求項9]
 請求項1~5のいずれかに記載の銅粒子混合物を、大気中で、常圧で、150℃以下の温度で焼結させる、銅粒子混合物の焼結方法。

[請求項10]
 銅微粒子A及び銅ナノ粒子Bを含む銅粒子混合物の製造方法であって、
(1)酢酸銅と、炭素数3~6の1級アルコール、炭素数3~6の2級アルコール及びそれらの誘導体からなる群より選択される少なくとも1種とが、炭素数2~4のジオールに溶解した溶液を調製する工程1、
(2)前記溶液を大気圧下で100℃以下でヒドラジン還元して、前記溶液中で銅ナノ粒子Bを調製する工程2、及び
(3)前記銅ナノ粒子Bを含有する前記溶液に、前記銅微粒子A、並びにマロン酸及びシュウ酸からなる群より選択される少なくとも1種のジカルボン酸を添加する工程3
を有し、
 前記銅微粒子Aは、平均粒子径が0.1μm以上5μm以下であり、マロン酸及びシュウ酸からなる群より選択される少なくとも1種のジカルボン酸により被覆されており、
 前記銅ナノ粒子Bは、銅の単結晶からなる中心部、及びその周囲の保護層からなり、前記銅ナノ粒子Bの平均粒子径が1nm以上100nm未満であり、
 前記銅ナノ粒子Bの保護層は、炭素数3~6の1級アルコール、炭素数3~6の2級アルコール及びそれらの誘導体からなる群より選択される少なくとも1種を含む、
ことを特徴とする銅粒子混合物の製造方法。

  • Applicant
  • ※All designated countries except for US in the data before July 2012
  • THE SCHOOL CORPORATION KANSAI UNIVERSITY
  • Inventor
  • KAWASAKI, Hideya
IPC(International Patent Classification)

PAGE TOP

close
close
close
close
close
close