JPH04164812A - Copper oxide ultra-fine particle - Google Patents

Abstract

PURPOSE:To obtain copper oxide ultra-fine particles by a simple production means at a low cost and in an easily industrially mass-producible state by adding a copper alkoxide to a specific W/O micro-emulsion phase. CONSTITUTION:A copper alkoxide is added to and hydrolyzed in a surfactant- water-nonpolar organic liquid system or surfactant-water-alkanol-nonpolar organic liquid system W/O micro-emulsion phase to form spherical or acicular copper oxide ultra-fine particles. When an oil-soluble surfactant is employed in the production of the ultra-fine particles, an alcohol, fatty acid, nonionic surfactant, etc., may be suitably added to the oil-soluble surfactant. When a water-soluble surfactant is employed in the production of the ultra-fine particles, the alcohol, fatty acid, nonionic surfactant, alkanol, etc., is added to the water- soluble surfactant to make oil-soluble.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to copper oxide ultrafine particles, and more specifically, to specific W/O particles.
This invention relates to ultrafine copper oxide particles produced by hydrolyzing copper alkoxide in a microemulsion phase.

[Prior Art] Recently, research has been carried out on ultrafine metal oxide particles, and the expansion of their uses has also been greatly studied. There are various methods for producing ultrafine metal oxide particles, such as physical methods and chemical methods (dry method, wet method), but the ones currently being mainly used industrially are physical methods. This is the evaporation method in a gas, and there are examples of copper oxide being produced using this method. Furthermore, copper oxide is also produced by a pulverization method or a wet method. Note that the term "ultrafine particles" as used herein refers to particles with a particle size of 1,000 Å or less, particularly 500 Å or less.

[Problems to be Solved by the Invention] However, in the case of copper oxide, it is difficult to produce ultrafine particles using the above-mentioned pulverization method or wet method, and the particle size tends not to be uniform. be. Furthermore, although the above-mentioned in-gas evaporation method is capable of producing ultrafine particles with a sharp particle size distribution, it requires a high temperature of 1,300 to 1,500° C., requires a complicated and large-scale apparatus, and has the disadvantage of high production costs.

The present inventors have developed ultrafine metal oxides obtained by hydrolyzing metal alkoxides or orthosilicates in a specific W/O microemulsion phase, as having simple manufacturing means and facilitating industrial mass production. first made a proposal regarding silicon oxide (Japanese Unexamined Patent Publication No. 6
3-185802). However, in the publication, the metal oxides specifically mentioned are A℃, Z
There were only oxides of r and ■.

Therefore, the present inventors conducted further studies to solve the above-mentioned problems, and as a result, they arrived at the present invention.

Therefore, an object of the present invention is to provide ultrafine copper oxide particles that have simple manufacturing means, low manufacturing costs, and can be easily mass-produced on an industrial scale.

[Means for Solving the Problems] According to the present invention, a copper alkoxide is added to a W/O microemulsion phase of a surfactant-water-nonpolar organic liquid system or a surfactant-water-alkanol-nonpolar organic liquid system. The present invention provides spherical or acicular ultrafine copper oxide particles produced by carrying out a hydrolysis reaction.

To explain the present invention in more detail below, the ultrafine particles in the present invention are copper oxides having a particle size/O00 Å or less, particularly 500 Å or less, on which a water-soluble or oil-soluble nonionic surfactant is adsorbed or attached. , generally obtained as a dispersed state in a nonpolar organic solvent. However, when an oil-soluble surfactant is used in the production of the ultrafine particles of the present invention, the oil-soluble surfactant alone may be used, but alcohol, fatty acid, nonionic surfactant, alkanol may be used as appropriate. etc. may be added. - On the other hand, if a water-soluble surfactant is used, it must be made oil-soluble (if necessary, alcohol, fatty acids, nonionic surfactants, alkanols, etc. may be added to make it oil-soluble and prevent the formation of ultrafine particles). Therefore, the above-mentioned dispersoid ultimately exhibits a state in which the periphery of the core ultrafine copper oxide particles is coated with an oil-solubilized surfactant.

By the way, W/O microemulsions consisting of three components (surfactant, water, non-polar organic liquid) or four components (surfactant, water, alkanol, non-polar organic liquid) are highly dispersed systems of water and thermodynamically It is a stable solution.

Representative examples of water-soluble or oil-soluble surfactants used in the production of ultrafine copper oxide particles according to the present invention include: (1) R'O3OsM (where R' is a chain hydrocarbon of 06 to CI2; , preferably a saturated or unsaturated chain hydrocarbon, more preferably an alkyl group. M is an alkali metal or an alkaline earth metal.) (2) 8) oso, y (However, R1 and M is the same as (1) above.) (3
) R'SO,M (However, R' and M are the same as in (1) above.) (4
)R1-@;? -5O8M (However, R' and M are the same as in (1) above.) (5
) R”N”(CHx)s ・X- (However, R2 is C6
-C2° alkyl group, X- is a halogen ion.

) (6) R2N"R3・X- (However, R2 and X- are the same as in (5) above.) (
However, R2 and X- are the same as in (5) above. ) (However, R3 is a 04-C8 noalkyl group, 2 is -3O3H1
It is an alkali metal or alkaline earth metal salt of -O303H or -COOH. ) (9) R30CH2CHCH2OR" (However, R3 and Z are the same as in (8) above.) (However, R" and 2
is the same as (8) above. )l (However, R3 and 2 are the same as in (8) above.) (However, R4 and R5 are both alkyl groups, and the total number of carbon atoms in both alkyl groups is 10 to 36.X - is a halogen ion.) (However, R', R@ and X- are the same as in (12) above.) (14) R6NHffCOOCR' (However, R6 is C6 to C18, preferably C, and R7 is a chain hydrocarbon of 01 to Cl18, preferably C2.

Examples of alcohols, fatty acids, nonionic surfactants and/or alkanols (anionic surfactants manufactured by DuPont, USA) that can be added to these surfactants include the following.

(a) Alcohol (having 1 to 20 carbon atoms, preferably 1 to 20 carbon atoms)
(b) Fatty acid (having 1 to 20 carbon atoms, preferably 1 to 20 carbon atoms)
(c) R'+0(CH, CH2OsuH (however, R' is a chain hydrocarbon having 1 to 20 carbon atoms, preferably 1 to /O, more preferably a saturated or It is an unsaturated chain hydrocarbon, more preferably an alkyl group, and n is 1 to 20.
, preferably an integer from 1 to lO. ) (d) R'-0 CH2CH2OsuH (However, R' is the same as the above formula (c). n' is an integer from 1 to 20, preferably from 4 to IO.) CH, OH ( However, rt9 is a chain hydrocarbon having 8 to 20 carbon atoms, preferably a saturated or unsaturated chain hydrocarbon, and more preferably an alkyl group.) (f) R/OCO-+
CH2CH2O+T-OH (however, R+o has 4 carbon atoms
-20, preferably 8-18 chain hydrocarbons, more preferably saturated or unsaturated chain hydrocarbons, more specifically an alkyl group, and n is the same as in formula (c) above. ) (However, R9 is the same as the above formula (E).) (H)
HO-(C2H, Ote → C3H60h IkuC, H40zeH
(However, n is an integer of 1 to /O, preferably 1 to 3, and m is an integer of 5 to 20, preferably 5 to 1O.) (S) Alkylaryl sulfonate.

These surfactants (including alkanols), alcohols, fatty acids, etc. may be used alone or in combination of two or more.

The non-polar organic liquid is primarily present as a non-aqueous dispersion medium when the dispersion is prepared. Various organic liquids (organic solvents) are used, but typical examples include kerosene, Isopar H (trade name,
Petroleum hydrocarbons such as ethane (manufactured by Standard Oil Co.);
Nonpolar hydrocarbons such as hexane, octane, cyclohexane, cyclobencune, benzene, toluene, and xylene; halogenated hydrocarbons such as carbon tetrachloride, trichloroethylene, tetrachloroethane, and dichlorobenzene; ethers such as diethyl ether and isopropyl ether;
Examples include esters such as ethyl acetate, propyl acetate, and phenylacetate; alcohols such as octyl alcohol, nonyl alcohol, decyl alcohol, and benzoyl alcohol; among them, use of cyclohexane is particularly effective. These solvents may be used alone or in combination of two or more.

In order to produce the copper oxide ultrafine particles of the present invention, copper alkoxide is simply added to the above-mentioned ternary or quaternary W/O microemulsion phase and hydrolyzed.

In this case, it is even more advantageous to carry out the hydrolysis in the presence of a catalyst. As the catalyst, alkali (such as NaOH), ammonia, etc. can be used.

Further, the production of ultrafine copper oxide particles by the hydrolysis reaction of copper alkoxide is preferably carried out under stirring conditions.

In the microgel dispersion containing ultrafine copper oxide particles of the present invention produced by It is in a state of being dispersed in an organic solvent.

Since the microgel itself in the present invention is water-insoluble, it can be dispersed in both aqueous and oil-based systems. Therefore, in the production of the ultrafine particles of the present invention, it is possible to change the dispersion medium from the organic solvent to water later if necessary.

Examples of the alkyl group of the copper alkoxide used in the present invention include methyl group, ethyl group, propyl group, and butyl group.

In the present invention, by selecting the adjustment conditions, the particle size is approximately 50%.
At 0 Å or less, ultrafine particles having a spherical or acicular shape and a sharp particle size distribution can be obtained.

[Example] Next, the present invention will be explained in more detail with reference to Examples.

Example 1 NP-6: CJ+o+0-+cH2cH2oH was used as a surfactant, cyclohexane was used as a nonpolar organic solvent,
Furthermore, copper oxide ultrafine particles were prepared using copper di-normal butoxide as an alkoxide.

First, add ammonia water to 0.1 mol・kg-' NP
-6/Solubilized in cyclohexane solution. While stirring this with a magnetic stirrer, 0.05 mol/kg of copper di-normal butoxide was pulverized under low humidity.
-1 concentration, and stirring was continued to advance the hydrolysis reaction. After a certain period of time, the resulting dispersion of ultrafine particles was sampled onto a Formvar film spread on a sheet mesh, and the shape, particle size, etc. of the particles were observed using a transmission electron microscope.

The concentrations of ammonia and water in the solubilized solution are Ra: [NH-]/[NP-6], Rw: [
Defined as H2O1/ [NP-6], various Ra,
When ultrafine particles were prepared using a solubilized solution of Rw, spherical ultrafine particles with little aggregation were obtained because of N.
In the solubilization phase diagram of the P-6/cyclohexane/ammonia aqueous system (Fig. 1), this was the part shown in perspective view A.

The average particle size was about 300 particles, and the produced particles were identified as CuO by X-ray diffraction (Figure 2).

Example 2 Particles were prepared using the solubilizing solution of Example 1 without adding ammonia as a catalyst (i.e., Ra: 0, the part shown in perspective B in FIG. 1), and the average particle width was approximately Acicular particles of 200 particles and an average particle length of about /000 particles were obtained.

[Effects of the Invention] The ultrafine copper oxide particles of the present invention have a particle size of about 500 and are obtained by a simple process of preparing a W/O microemulsion, adding copper alkoxide thereto, and performing a hydrolysis reaction.
Since they are ultrafine particles with a particle diameter of Å or less, spherical or acicular, and with a sharp particle size distribution, they are characterized by simple manufacturing methods, low manufacturing costs, and easy industrial mass production.

[Brief explanation of the drawing]

FIG. 1 is a solubilization phase diagram of the NP-6/cyclohexane/ammonia aqueous system in Example 1, and FIG. 2 is an X-ray diffraction diagram of the particles produced in Example 1. Applicant Rico Co., Ltd. −

Claims (2)

[Claims] (1) Manufactured by adding copper alkoxide to a W/O microemulsion phase of a surfactant-water-nonpolar organic liquid system or a surfactant-water-alkanol-nonpolar organic liquid system and performing a hydrolysis reaction. Ultrafine spherical copper oxide particles. (2) Manufactured by adding copper alkoxide to a surfactant-water-nonpolar organic liquid system or a surfactant-water-alkanol-nonpolar organic liquid system W/O microemulsion phase and performing a hydrolysis reaction. Ultrafine acicular copper oxide particles.