KR20140145116A - Nanoparticle dispersion, nanoparticle-carrying powder, and processes for manufactruing same - Google Patents

Abstract

Provided is a method for producing a nanoparticle dispersion which enables nanoparticles to be stably dispersed without aggregation. The pulverizing material 5 to be converted into nanoparticles is immersed in the solvent 4 of the treatment vessel 3, pulsed laser is applied to the pulverized material, the pulverized material is light pulverized into nano-sized particles, A method for producing a nanoparticle dispersion liquid in which particles (P) are dispersed and an ultrasonic wave is irradiated to a nanoparticle dispersion liquid to prevent agglomeration of the nanoparticles in the nanoparticle dispersion, And has a wavelength longer than that of an absorption band due to a unique electron transition of the material to be crushed.

Description

TECHNICAL FIELD [0001] The present invention relates to a nanoparticle dispersion, a nanoparticle-bearing powder, and a method of manufacturing the nanoparticle dispersion.

TECHNICAL FIELD The present invention relates to a nanoparticle dispersion, nanoparticle-bearing powder, and a method for producing the same.

Platinum has a chemically stable property and is excellent in catalytic function for promoting a chemical reaction and is used as a material for various purposes such as an exhaust gas treatment of an automobile or an electrode of a fuel cell. It is also used as a biosensor using optical properties of platinum, food products using antioxidative properties, and cosmetics.

In addition, cisplatin or carboplatin, for example, is known as an antitumor agent for the platinum complex, and the application range of platinum is wide.

However, since platinum is very expensive, when platinum is used as a catalyst, it is necessary to use the platinum material efficiently so that a high effect can be obtained as small as possible.

It is generally known that a platinum nanocolloid solution widely used as a platinum material is coated with a polymer such as citric acid, ascorbic acid, or sodium polyacrylate by dispersing and suspending platinum nanoparticles in a solvent such as water.

It is inevitable to disperse and stabilize the metal nanoparticles in a solvent in order to avoid the aggregation of platinum nanoparticles and the like in order to produce a metal nanoparticle dispersion liquid of platinum, gold, silver, or palladium having a high function.

Therefore, when preparing a nanocolloid solution of a metal, the periphery of the metal nanoparticles is usually coated with a polymer as a dispersion stabilizer (protective agent) of the metal nanoparticles. Therefore, in the colloid solution containing the protective agent, the protective agent is adsorbed on the surface of the metal colloid particles, so that the direct contact between the metal nanoparticles is suppressed, and the aggregation or precipitation of the metal nanoparticles can be prevented.

However, when preparing a catalyst (platinum catalyst or the like) with a metal nano-colloid solution, it is necessary to remove the above-mentioned dispersion stabilizer (protective agent). Therefore, depending on the use of the metal nanoparticles, it may be required to provide a dispersion of metal nanoparticles or a metal nanoparticle powder not containing a protective agent. However, the dispersion of the metal nanoparticles not containing the protective agent tends to cause coagulation or sedimentation at the time of production as compared with the metal colloid solution containing the protective agent, and it is difficult to store the metal colloid solution for a long period of time even after storing the metal colloid solution.

In view of such a problem, a platinum colloid solution which does not cause aggregation or precipitation and does not contain a protective agent excellent in long-term stability is described in Patent Document 1. [

Japanese Patent Application Laid-Open No. 2009-84250

Patent Document 1 discloses a platinum colloid solution containing no platinum colloid composed of platinum particles and a solvent consisting of water or a mixed solvent of water and an organic solvent. The platinum colloid solution has a platinum content of 300 to 20,000 ppm and a pH Of 5.0 to 12.0 and an electric conductivity of 100 mS / m or less.

However, in Patent Document 1, there is a problem that the operation of adjusting the pH and the like is troublesome when the platinum nanocolloid solution is prepared. In addition, there is a problem that conditions for producing a platinum colloid solution are limited.

In addition, since the periphery of the platinum nanoparticles is covered with a film of an organic substance, the antioxidant ability of the platinum itself can not be exerted and the original action of the platinum nanoparticles can not be exerted.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and it is an object of the present invention to provide a nanoparticle dispersion liquid which can be stably dispersed without agglomeration of nanoparticles such as platinum, a method of producing nanoparticle- A nanoparticle dispersion, and a nano-particle-bearing powder.

(1) A process for producing a nanoparticle dispersion of the present invention is a process for producing a nanoparticle dispersion, which comprises immersing a material to be nanoparticles into a solvent of a treatment vessel, irradiating the material to be pulsed with a pulsed laser, A method for producing a nanoparticle dispersion liquid in which ultrasonic waves are irradiated to a dispersion of nanoparticles in which nanoparticles are dispersed in a solvent by light pulverization to prevent agglomeration of the nanoparticles in the dispersion of nanoparticles,

The pulsed laser has a longer wavelength than an absorption band due to a unique electron transition of the material to be crushed.

(2) The method for producing a nanoparticle dispersion of the present invention is characterized in that, in the above (1), the surface of the material to be crushed is covered with a film having a laser absorbing function.

(3) The method for producing a nanoparticle dispersion of the present invention is characterized in that, in the above item (1) or (2), the material to be crushed is plate-shaped.

(4) The method for producing a nanoparticle dispersion of the present invention is characterized in that, in the above items (1) to (3), the crushed material is in the form of particles.

(5) The method for producing a nanoparticle dispersion of the present invention is characterized in that, in the above (1) to (4), the solvent is water.

(6) The method for producing a nanoparticle dispersion of the present invention is characterized in that in the above (1) to (5), a temperature adjusting mechanism for adjusting the temperature of the nanoparticle dispersion liquid is provided in the processing vessel.

(7) A method for producing a nanoparticle dispersion of the present invention is characterized in that the process liquid introduction pipe is formed outside the process container and the solvent and the material to be crushed are introduced into the process solution introduction And introducing the pulsed laser into the pipe, and irradiating the pulsed laser toward the treatment liquid introduction pipe to crush the crushed material into nano-sized particles.

(8) The method for producing a nanoparticle-bearing powder of the present invention is a method for producing a nanoparticle dispersion by mixing base particles having an outer diameter larger than that of the nanoparticles in the dispersion of nanoparticles produced by any one of the above- And drying the mixed solution by a spray drying method to carry the nanoparticles on the surface of the base particles.

(9) The nanoparticle dispersion of the present invention is obtained by immersing a to-be-crushed material to be nanoparticles into a solvent of a treatment vessel, pulverizing the crushed material with nano-sized particles by irradiating the pulsed material with a pulsed laser A nanoparticle dispersion in which nanoparticles are dispersed in a solvent, wherein the nanoparticle dispersion is prepared by irradiating ultrasound waves to the nanoparticle dispersion so as to prevent agglomeration of the nanoparticles in the nanoparticle dispersion, And a wavelength longer than an absorption band caused by a unique electron transition of the material to be crushed.

(10) The nanoparticle dispersion of the present invention is characterized in that, in the above (9), the surface of the material to be crushed is covered with a coating having a laser-absorbing function.

(11) The nanoparticle dispersion of the present invention is characterized in that, in the above (9) or (10), the material to be crushed is plate-shaped.

(12) The nanoparticle dispersion of the present invention is characterized in that, in the above (9) to (11), the material to be crushed is in the form of particles.

(13) The nanoparticle dispersion of the present invention is characterized in that, in the above (9) to (12), the solvent is water.

(14) The nanoparticle dispersion of the present invention is characterized in that, in the above (9) to (13), a temperature regulating mechanism for regulating the temperature of the nanoparticle dispersion liquid is provided in the processing vessel.

(15) The nanoparticle dispersion of the present invention is the nanoparticle dispersion liquid according to any one of (9) to (14) above, wherein the treatment liquid introduction pipe is formed outside the treatment container, and the solvent and the crushing material are introduced into the treatment solution introduction pipe And irradiating the pulsed laser toward the treatment liquid introduction pipe to crush the crushed material into nano-sized particles.

(16) The nanoparticle-bearing powder of the present invention is produced by preparing a mixed solution obtained by mixing base particles having an outer diameter larger than that of the nanoparticles in the nanoparticle dispersion described in any one of (9) to (15) Is dried by a spray drying method, and the nanoparticles are carried on the surface of the base particles.

According to the present invention, ultrasonic irradiation for preventing coagulation is performed along with laser light irradiation for light pulverization of a liquid to be treated, light pulverization of the material to be crushed into nano-sized particles is efficiently carried out, Can be dispersed in a solvent such as water. In addition, the nanoparticle dispersion obtained in the present invention can be carried on the surface of particles larger than the nanoparticles and dried to form nanoparticle-carrying powders.

The nanoparticle-carrying powder obtained in the present invention has effects such as antioxidative action, antibacterial activity, deodorization action and further anticancer activity, which are possessed by the nanoparticles, and is supported on the surface of particles larger than the nanoparticles. Defects of the particles can be compensated.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram showing a method for producing a nanoparticle dispersion according to Embodiment 1 of the present invention. FIG.
Fig. 2 is an explanatory view showing a production flow of the nanoparticle dispersion of Embodiment 1 of the present invention. Fig.
3 is a schematic diagram showing a method for producing a nanoparticle dispersion liquid according to Embodiment 2 of the present invention.
4 is a graph showing the particle diameter distribution of the nanoparticles obtained by the production method of Embodiment 1 of the present invention.
5 is a schematic diagram showing a method for producing a nanoparticle dispersion liquid according to Embodiment 3 of the present invention.
6 is a schematic diagram showing a method for producing a nanoparticle dispersion liquid according to Embodiment 4 of the present invention.
7 is a schematic diagram showing a method for producing a nanoparticle dispersion liquid according to Embodiment 4 of the present invention.
8 is a diagram showing a production flow of a nanoparticle dispersion of Embodiment 4 of the present invention.
Fig. 9 is a schematic view showing the appearance of the nano-particle-bearing powder of the present invention. Fig.

A method for producing a nanoparticle dispersion of an embodiment of the present invention is a method for manufacturing a nanoparticle dispersion of the present invention by immersing a to-be-crushed material to be nanoparticles into a solvent of a treatment vessel, irradiating the pulsed material with a pulsed laser, The nanoparticle dispersion is prepared by dispersing the nanoparticles in the solvent by light pulverization. In order to prevent agglomeration of the nanoparticles in the dispersion of nanoparticles, ultrasonic waves are irradiated to the nanoparticle dispersion. Here, it is important that the pulse laser has a wavelength longer than that of the absorption band due to the unique electron transition of the material to be crushed.

Further, in consideration of the fact that the pulsed laser utilizes the principle of the liquid-phase laser ablation method and reduces the photodegradation of the nanoparticles, an infrared pulse laser may be used.

Examples of the material to be crushed to be formed into nanoparticles include metal materials and ceramics. Examples of the metal material include platinum, silver, copper, gold, palladium, cobalt, titanium, or an alloy containing them. Examples of the ceramics material include silica, alumina, zirconia, silicon carbide, titanium oxide, or a composite ceramics material And the like.

Platinum is a particle made of a platinum group metal and containing 99 mass% or more of platinum. The average particle diameter when nanoparticles are formed is preferably 5 to 50 nm, particularly preferably 10 to 30 nm. Particularly, when the average particle diameter is in the range of 10 to 30 nm, the effects of the antioxidative, antibacterial, and anticancer activities of the platinum nanoparticles can be enhanced.

The shape of the material to be crushed is preferably a plate shape or a particle shape in order to form a nanoparticle in a solvent using a laser. Considering the light-breaking efficiency of the laser, it is preferable that the thickness of the plate-shaped raw material is about 0.1 mm to 1 mm, and the diameter of the raw material of the particle shape is about 0.1 mm to 1 mm.

It is also preferable to perform a treatment of covering the surface of the material to be crushed with a film having a laser-absorbing function in order to efficiently perform nanoparticle-forming of the material to be crushed in a solvent.

In addition, by performing the treatment of covering the surface of the material to be crushed with a film having a laser-absorbing function, the energy of the pulse laser can be efficiently absorbed and the optical crushing can be performed efficiently. Examples of the coating having a laser absorbing function include coatings such as a laser absorbing dye, a pigment absorbing dye (carbon black, etc.), a light absorbing resin and the like.

The solvent may be an organic solvent or a liquid such as water. However, in consideration of cost and safety, it is preferable to use water. In order to sufficiently prevent agglomeration of the nanoparticles, a dispersant may be added to the solvent. As the dispersing agent, a surfactant is suitably used.

It is also preferable that a temperature adjusting mechanism for adjusting the temperature of the nanoparticle dispersion liquid is provided in the processing vessel. In other words, it is possible to cool the processing vessel to reduce deterioration of the quality of nanoparticles of the material to be crushed, and to prevent condensation on the surface of the processing vessel. When condensation forms on the surface of the processing container, the efficiency of nanoparticle formation is reduced due to scattering of the laser light, and this temperature adjusting mechanism has a role as a dew condensation preventing function. As the temperature adjusting mechanism, there can be mentioned a processing chamber for cooling the outer periphery of the processing vessel and the like.

Further, after the process liquid introduction pipe is formed outside the process vessel, the solvent and the material to be crushed are introduced into the process liquid introduction pipe, and the pulse laser is irradiated toward the process liquid introduction pipe, It is also possible to perform optical pulverization with nano-sized particles. By passing the material to be crushed through the treatment liquid introduction pipe, the material to be crushed can be efficiently light-crushed.

The method for producing a nano-particle-bearing powder of the present invention is characterized in that a mixed solution obtained by mixing base particles having an outer diameter larger than that of the nano-particles in the nano-particle dispersion prepared by any one of the above-mentioned production methods is prepared, Drying method, and the nanoparticles are supported on the surface of the base particles. By the spray drying method, a plurality of nanoparticles can be supported on the surface of the base particles having a large outer diameter.

In addition, it is preferable that a plurality of nanoparticles are carried on the surface of the base particles, and then dried at a high temperature of about 100 to 200 DEG C to firmly support the nanoparticles.

Examples of the base particles include metal materials, ceramics materials, and organic materials. Examples of the metal materials include platinum, silver, copper, gold, palladium, cobalt, titanium or their alloys. Examples of the ceramics materials include silica, alumina , Zirconia, silicon carbide, titanium oxide, zinc oxide, calcium carbonate, and the like, or a composite ceramics material containing them.

Examples of the organic substance include food, medicine, and plastic. Examples of foods and medicines include organic substances such as vitamin C, hyaluronic acid, collagen, astaxanthin, and placenta extract.

The size of the base particles is preferably about 1 to 100 mu m, but the size is not limited as long as it is larger than the nanoparticles. By supporting a plurality of nanoparticles on the surface of a base particle having a large outer diameter, handling of the nanoparticles is facilitated even in a dry state.

In the preparation of the mixed solution in which the base particles are mixed with the nanoparticle dispersion, the nanoparticle dispersion and the base particles may simply be mixed. However, an organic or inorganic binder may be added to firmly support the nanoparticles on the base particles.

As the organic binder, an adhesive may be mentioned. As the inorganic binder, colloidal silica may be mentioned.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a preferred embodiment of a method for producing a nanoparticle dispersion according to the present invention will be described in detail with reference to the drawings.

≪ Embodiment 1 >

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram showing a method for producing a nanoparticle dispersion according to Embodiment 1 of the present invention. FIG. In Fig. 1, reference numeral 1A is a device for producing a nano-particle dispersion for producing nanoparticles by light-pulverizing a material to be treated in a solvent of the liquid to be treated. The liquid to be treated 2 is composed of liquid 4 as a solvent and particles 5 of the material to be nano-particles to be contained in the water 4. In the first embodiment, a particle-shaped material was used as the material to be crushed.

As shown in Fig. 1, the manufacturing apparatus 1A used in the method of manufacturing the nanoparticle dispersion of Embodiment 1 is provided with a processing vessel 3 for accommodating a liquid to be treated 2. As shown in Fig. The processing vessel 3 is made of quartz, for example. (Temperature adjusting mechanism) 13 is provided so as to cover the processing vessel 3. As shown in Fig. The constant temperature apparatus 13 has a function as a cooling means for cooling the liquid to be treated 2 in the processing vessel 3 and keeps the liquid to be treated 2 cooled at a low temperature at a constant temperature. By cooling the liquid to be treated 2 in this way, oxidation of the nanoparticles can be prevented and the light-breaking efficiency can be improved.

The manufacturing apparatus 1A is provided with a high power laser light source 10 for irradiating a liquid to be treated 2 contained in the processing vessel 3 with laser light of a predetermined wavelength. The laser light source 10 supplies a laser beam of a suitable wavelength in order to nano-granulate the raw material particles 5 of the light pulverized material in the water 4 as the liquid 2 to be treated.

As the laser light source 10, a wavelength-fixed laser light source can be used when the wavelength to be set in the laser light is previously known. Alternatively, a wavelength variable laser light source may be used as the laser light source 10. In this case, laser light having an appropriate wavelength can be appropriately set and irradiated on the basis of the light absorbing characteristic of the light-sensitive photoresist. If necessary, a light intensity adjusting means such as an attenuating filter or an optical attenuator may be provided in the laser light source 10.

A magnet stick 11 is accommodated in the processing vessel 3 together with the liquid to be treated 2. The magnet stick 11 and the magnet stirrer 12 stir the water to be treated 2 and the raw material particles 5 in the processing vessel 3 and mix the raw material particles 5 in the water 4, Is used to disperse.

An ultrasonic transducer driving device 25 for driving and controlling the ultrasonic transducer 20 and the ultrasonic transducer 20 is provided at a predetermined position outside the processing container 3. [ The ultrasonic transducer 20 is an ultrasonic wave irradiating means for irradiating ultrasound to the object liquid 2 in the processing vessel 3 to prevent agglomeration of the nanoparticles. The ultrasonic vibrator 20 is configured such that the processing vessel 3 is capable of irradiating the object liquid 2 with ultrasonic waves using resonance vibration.

In the present embodiment, the ultrasonic transducer 20 is disposed on one side of the processing vessel 3. A microphone 30 is mounted on the opposite side of the processing container 3 as seen from the ultrasonic vibrator 20. The microphone 30 and the vibration amplitude measuring device 35 constitute a vibration amplitude monitor means for monitoring the vibration amplitude of the processing container 3 by ultrasonic wave irradiation.

The laser light source 10 and the vibrator driving device 25 are connected to a control device 15 such as a computer. In this embodiment, the control device 15 is also connected to the magnet stirrer 12, the constant temperature device 13, and the vibration amplitude measuring device 35.

The control device 15 controls the manufacture of nanoparticles by controlling the operation of each part of the manufacturing apparatus 1A described above. The manufacturing apparatus is equipped with facilities capable of irradiating laser light (optical fracturing) and ultrasonic irradiation while cooling the liquid to be treated. Thereby, a platinum nanoparticle dispersion (an aqueous solution in which platinum nanoparticles are dispersed) can be efficiently produced from the platinum particles.

Next, a method for producing a nanoparticle dispersion liquid using the production apparatus 1A shown in Fig. 1 will be described. Fig. 2 is a manufacturing flow showing a method for producing a nanoparticle dispersion liquid in which platinum nanoparticles as nanoparticles are dispersed in the present embodiment.

First, the target liquid 2 is prepared by mixing water 4 as a solvent and platinum particles (raw material particles 5) as raw materials and introduced into the processing vessel 3 (S101). Next, the constant-temperature device 13 is driven to cool the object to be treated 2 in the processing vessel 3 and the processing vessel 3 to a predetermined low temperature (S102). Then, the micro-agitator 12 is operated to stir the target liquid 2 with the magnet stick 11 to disperse the raw material particles 5 in the water 4 (S103).

Subsequently, the frequency of ultrasonic waves to be irradiated on the liquid to be treated 2 is set (S104). First, as described above, the ultrasonic vibrator 20 is driven by the vibrator driving device 25 in the state of cooling by the constant-temperature device 13 and stirring by the magnet stick 11, 3) and the liquid to be treated (2). The microphone 30 monitors the vibration amplitude of the processing container 3 by ultrasonic irradiation and outputs an electric signal indicating the monitoring result to the control device 15 through the vibration amplitude measuring device 35. [

The control device 15 refers to the information on the frequency of the ultrasonic wave from the vibrator driving device 25 and the information on the monitoring result from the vibration amplitude measuring device 35 to determine the vibration frequency of the ultrasonic wave being irradiated And the vibration amplitude (vibration intensity) of the container 3 is obtained. Then, the frequency of ultrasonic waves to be irradiated on the liquid to be treated 2 is set on the basis of the relationship between the oscillation frequency and the amplitude. Concretely speaking, the frequency at which the vibration amplitude becomes the maximum becomes the resonance vibration frequency in the processing container 3 in the relationship between the obtained frequency and amplitude. Therefore, the frequency of the ultrasonic waves irradiated from the ultrasonic vibrator 20 to the processing container 3 The frequency is set to the resonance vibration frequency through the vibrator driving device 25. [

Next, the laser light source 10 is controlled by the control device 15 and laser light having a wavelength set in accordance with the light absorbing characteristic of the material constituting the raw material particles 5 is emitted from the laser light source 10 (2). By this laser light irradiation, the raw material particles 5 in the water 4 in the liquid to be treated 2 in the processing vessel 3 are light-broken into nano-sized particles (light pulverization processing = nanoparticle formation processing).

Along with the irradiation of the laser light, ultrasonic waves are applied to the processing vessel 3 and the liquid to be treated 2 by the ultrasonic vibrator 20. By this ultrasonic irradiation, aggregation of the nanoparticles produced in the water 4 is prevented (S105).

Subsequently, the progress of the light pulverizing process in the target liquid 2 is confirmed (S106). Then, if the progress state does not satisfy the completion condition of the predetermined optical crushing process (nanoparticle formation), the optical crushing by the laser irradiation is further continued.

On the other hand, if it is determined that the progress state satisfies the completion condition of the optical crushing treatment and the raw material particles are made into nanoparticles in the whole of the liquid to be treated 2, the laser light irradiation and the ultrasonic wave irradiation are stopped (S107) The processing is terminated.

In the present embodiment, laser light is irradiated to the liquid to be treated 2 containing the raw grain 5 by the laser light source 10 for nanoparticle formation and by the ultrasonic oscillator 20 for prevention of coagulation Ultrasonic irradiation is simultaneously carried out. Thereby, it becomes possible to carry out the optical crushing treatment by laser light irradiation while suppressing the agglomeration progress of the nanoparticles produced in the water 4.

That is, by irradiating the object liquid 2 with ultrasonic waves, it is possible to prevent the aggregation of the nanoparticles of the smallest mass and further redisperse the aggregated mass immediately after the aggregation. Therefore, by using ultrasonic irradiation together with laser light irradiation, it is possible to effectively suppress the occurrence of agglomeration due to agglomeration of the nanoparticles produced in the liquid to be treated 2.

In addition, since aggregation of nanoparticles is prevented in this way, deterioration in the efficiency of nanoparticle formation caused by aggregated nanoparticles becoming a scattering body for laser light is prevented. Therefore, it becomes possible to efficiently make the material nanoparticles.

Such a method of producing a nanoparticle dispersion using ultrasonic irradiation in combination is particularly effective when the concentration of nanoparticles is increased to efficiently make the material (the material to be broken) into nanoparticles. In other words, in order to improve the efficiency of nanoparticle formation by laser light irradiation, it may be necessary to increase the concentration of nanoparticles produced in the solvent to perform the nanoparticle formation treatment.

However, in the presence of high concentrations of nanoparticles, aggregation of the nanoparticles is likely to occur. For this reason, the efficiency of nanoparticle formation is reduced due to the scattering of the laser light in the aggregated nanoparticles, or the produced nanoparticles become defective with large variation in particle size.

On the other hand, by performing the ultrasonic irradiation simultaneously with the laser light irradiation as described above, it becomes possible to make the material to be crushed into nano-particles under favorable conditions even in the presence of such high-concentration nano-particles.

In the manufacturing apparatus 1A shown in Fig. 1, the ultrasonic wave irradiation by the ultrasonic vibrator 20 is performed by using the resonance vibration of the processing vessel 3 accommodating the liquid 2 to be treated. As a result, it is possible to appropriately realize prevention of agglomeration of the nanoparticles by irradiation with ultrasonic waves to the liquid to be treated 2. As the processing vessel 3, for example, it is preferable to use a vessel having a quadrangular prismatic, cylindrical, or spherical shape capable of resonant oscillation.

When the resonance vibration is used as described above, the durability of the processing vessel 3 against resonance vibration of the large vibration is required. However, by using a container such as a cylinder or a sphere to reduce the bonding portion weak in vibration, .

In the manufacturing apparatus 1A, the vibration amplitude of the processing container 3 is monitored by the microphone 30 and the vibration amplitude measuring device 35, and the frequency of the ultrasonic wave is set based on the monitor result. Thereby, the frequency of the ultrasonic waves can be set to a suitable frequency such as the resonance vibration frequency in the processing container 3, and it becomes possible to reliably prevent agglomeration of nanoparticles by ultrasonic irradiation. As the vibration amplitude monitor means, various sensors other than the microphone 30 can be used.

With regard to the agglomeration of nanoparticles in a solvent, the lower the solubility of nanoparticles is, the higher the cohesion is, and in such a case, the effect of preventing the agglomeration by the combined use of ultrasonic devices is great.

In the above embodiment, laser light irradiation and ultrasonic irradiation are performed while the liquid to be treated 2 is cooled by the constant-temperature device 13. Such cooling of the liquid to be treated 2 is effective in preventing oxidation of nanoparticles by laser light irradiation to improve light-breaking efficiency, and also contributes to lowering of the cohesive force of nanoparticles and formation of strong resonance oscillation fields do.

Here, it is preferable that the wavelength of the laser light irradiated from the laser light source 10 to the liquid to be treated 2 is longer than the wavelength of the light absorption band due to the electron transition of the substance to be converted into nanoparticles. In the case of a substance which needs to avoid photodegradation (photochemical reaction), it is preferably an infrared wavelength, more preferably 900 nm or more. Thereby, quality deterioration can be reduced and suitably realized in the optical crushing process.

As the laser light source 10, it is preferable to use a pulse laser light source. Particularly, in the case of exceeding the threshold value of the light intensity causing the optical crushing phenomenon, since the nanoparticle formation is performed with sufficient efficiency while suppressing the occurrence of extra photochemical reaction and thermal decomposition in the liquid to be treated 2, It is preferable to use a pulsed laser light source having a low sugar irradiation energy and a high repetition frequency.

In addition, in the apparatus 1A for producing a nanoparticle dispersion shown in Fig. 1, it is possible to suppress the stop of the laser light irradiation and the ultrasonic wave irradiation by obtaining the intensity and time of the laser light necessary for the optical crushing treatment in advance. Alternatively, monitor means for monitoring the state of nanoparticles of the raw material particles 5 in the liquid to be treated 2 may be provided, and control may be performed in accordance with the monitor result.

≪ Embodiment 2 >

3 is a schematic explanatory view showing a manufacturing method of the nanoparticle dispersion of Embodiment 2. Fig. The apparatus 1B used for producing the nanoparticle dispersion liquid includes a processing vessel 3 for containing a liquid to be treated 2 made of water 4 and raw material particles 5 of a material, a laser light source 10, The configuration of the stick 11, the magnet stirrer 12, the constant temperature device 13 and the control device 15 is the same as that of the production device 1A shown in Fig.

In the second embodiment shown in Fig. 3, the ultrasonic vibrator 21, which is the ultrasonic wave irradiating means, is disposed on the bottom surface side of the processing container 3. [ The ultrasonic transducer 21 is also provided with an ultrasonic transducer driving device 26 for driving and controlling the ultrasonic transducer 21. A signal from the vibrator driving device 26 is also input to the vibration amplitude measuring device 36. [ The vibration amplitude measuring device 36 measures the vibration amplitude of the processing container 3 by a signal from the vibrator driving device 26. [

The oscillation amplitude monitor means for monitoring the oscillation amplitude of the processing container 3 by ultrasonic wave irradiation is constituted by the ultrasonic oscillator 21, the oscillator driving device 26 and the oscillation amplitude measuring device 36 .

In the configuration in which the ultrasonic transducer 21 is provided on the bottom surface of the processing container 3 as described above, resonance vibration is formed between the bottom surface and the top surface of the water 4. [ At this time, when the resonance oscillation state is reached, the ultrasonic oscillator 21 vibrates greatly, and the voltage applied to the oscillator becomes large. Therefore, by monitoring the amplitude change of the voltage applied to the ultrasonic vibrator 21 by the vibration amplitude measuring device 36, the resonance vibration frequency in the ultrasonic irradiation can be obtained. In this case, there is an advantage that the microphone 30 shown in Fig. 1 and the like are not separately provided for the vibration amplitude monitor.

≪ Embodiment 3 >

Fig. 5 shows a method of producing the nanoparticle dispersion of Embodiment 3. Fig. In Embodiment 3, as in the nano-particle dispersion producing apparatus 1C shown in Fig. 5, the treatment liquid introduction pipe 40 is formed outside the treatment vessel 3, and the treatment liquid 2 is introduced into the treatment liquid 3 It may be introduced into the introduction pipe 40 and irradiated with a pulsed laser toward the treatment liquid introduction pipe 40 so that the material to be crushed may be light-crushed with nano-sized particles (nano-particles). The pulverizing material dispersed in the to-be-treated liquid 2 is passed through a narrow range of the processing liquid introducing pipe, whereby the pulsed laser can be focused and the optical pulverization can be efficiently performed.

≪ Fourth Embodiment >

Fig. 6 shows a method of producing the nanoparticle dispersion of Embodiment 4. Fig. In the method for producing a nanoparticle dispersion of Embodiment 4, as shown in Fig. 6, a plate 5 is used as a raw material. The thickness of the plate 5 is preferably about 0.1 mm to 1 mm in consideration of the light-breaking efficiency of the laser. The plate 5 to be a raw material is set up in the processing vessel 3 and a laser is irradiated from the direction perpendicular to the plane of the plate 5. [ Further, the control device 15 moves the laser light source or the plate so that the laser is scanned over the entire surface of the plate 5. [

The plate to be the raw material of the material to be crushed is usually set up in the processing vessel 3 so that one thin plate is perpendicular to the irradiation direction of the laser, but a plurality of plates may be laminated. In this case, it is preferable to coat the surface of the plate 5 with a coating film 5a having a laser-absorbing function (see Fig. 7 (a)) in order to efficiently perform nanoparticle formation in a solvent. Examples of the film 5a having a laser absorbing function include thin films of laser absorbing dye, pigment absorbing dye (carbon black, etc.), light absorbing resin and the like.

Further, as shown in Figs. 7 (b) to 7 (d), two or more raw material plates 5 may be stacked and installed. In this case, the raw plate 5 may be of a different kind. The film 5a may be sandwiched between the laminated plates.

Next, a method for producing a nanoparticle dispersion liquid using the production apparatus 1D shown in Fig. 6 will be described. Fig. 8 is a manufacturing flow showing a manufacturing method of a nanoparticle dispersion liquid in which platinum nanoparticles as nanoparticles are dispersed in the fourth embodiment.

First, the water 4 as the solvent and the plate 5 to be the object to be treated are immersed in the processing vessel 3 (S201). Next, the constant temperature apparatus 13 is driven to cool the solvent in the processing vessel 3 and the processing vessel 3 to a predetermined low temperature (S202). Then, the magnet stirrer 12 is operated, and the solvent is stirred by the magnet stick 11 (S203).

Subsequently, the frequency of the ultrasonic wave to be irradiated is set to the plate 5 to be processed (S204). First, as described above, the ultrasonic vibrator 10 is driven by the vibrator driving device 25 in the state of cooling by the constant temperature device 13 and stirring by the magnet stick 11, 3) and the solvent is irradiated with ultrasonic waves.

The microphone 30 monitors the frequency width of the processing container 3 by ultrasonic irradiation and outputs an electric signal indicating the monitoring result to the control device 15 through the vibration amplitude measuring device 35. [

The control device 15 refers to the information about the frequency of the ultrasonic wave from the vibrator driving device 25 and the monitoring result information from the vibration amplitude measuring device 35 to determine the vibration frequency of the ultrasonic wave being irradiated, 3) of the vibration amplitude (vibration intensity).

Then, the frequency of ultrasonic waves to be irradiated on the liquid to be treated 2 is set on the basis of the relationship between the oscillation frequency and the amplitude. Concretely speaking, the frequency at which the vibration amplitude becomes the maximum becomes the resonance vibration frequency in the processing container 3 in the relationship between the obtained frequency and amplitude. Therefore, the frequency of the ultrasonic waves irradiated from the ultrasonic vibrator 20 to the processing container 3 And the frequency is set to the resonance vibration frequency through the vibrator driving device 25. [

Next, the laser light source 10 is controlled by the controller 15, and laser light having a wavelength set in accordance with the light absorbing characteristic of the material constituting the raw material plate 5 is emitted from the laser light source 10 to the raw plate 5). By this irradiation of the laser beam, the raw plate 5 in the water 4 in the processing vessel 3 is light-shattered in nano-size.

Further, ultrasonic waves are applied to the processing container 3 and the solvent by the ultrasonic vibrator 20, together with the irradiation of the laser beam. By this ultrasonic irradiation, aggregation of the nanoparticles produced in the water 4 is prevented (S205).

Then, the progress of the light pulverizing process in the processing vessel is checked (S206). Then, if the progress state does not satisfy the completion condition of the predetermined optical crushing process (nanoparticle formation), the optical crushing by the laser irradiation is further continued.

On the other hand, if it is determined that the progress state satisfies the completion condition of the optical crushing process and that the entire raw material particles are made into nanoparticles, the laser light irradiation and the ultrasonic irradiation are stopped (S207), and the optical crushing process is terminated.

Fig. 9 is a schematic view showing the appearance of the nano-particle-bearing powder of the present invention. Fig. The nanoparticle-carrying powder (Q) shown in FIG. 9 is prepared by preparing a mixed solution obtained by mixing the nanoparticle dispersion prepared by one of the above methods with base particles (C) having an outer diameter larger than that of the nanoparticles (P) Drying the mixed solution by a spray drying method, and supporting the nanoparticles (P) on the surface of the base particles (C). The nano-particle-bearing powder (Q) dried by the spray-drying method is dried at a high temperature of about 100 to 200 ° C to firmly support a plurality of nanoparticles (P) on the surface of the base particle (C). The nano-particle-bearing powder (Q) shown in Fig. 9 supported platinum P (size: 10 nm) on the surface of silica (size: 10 m) as the base particles (C).

(Example)

In the present embodiment, platinum particles were used as raw material particles 5 to be formed into nanoparticles. Platinum is a very insoluble (poor solvent) pigment for water, and when it is nanoparticles it exhibits high cohesion in water. First, six samples were prepared in which 3 ml of platinum raw material particles having particle diameters of 10 to 70 占 퐉 were put in a quartz square cell as a treatment vessel (3) in a state of a high speed suspension having a concentration of 1 mg / ml. A quartz square cell having a size of 10 mm ㅧ 10 mm ㅧ 40 mm was used, and a piezoelectric vibrator having a diameter of? 16 mm and a thickness of 3 mm was mounted on the surface thereof as an ultrasonic vibrator 21 (see Fig. 3).

(B) ultrasonic wave processing only, (c) ultrasonic resonance processing only, (d) optical crushing processing only, (e) ultrasonic wave processing and optical fracturing Were treated at the same time but under different conditions. Then, the effect of the change of the particle diameter of platinum by each treatment was examined by a particle size distribution measuring apparatus (Shimadzu SALD 7000). All of these samples do not contain a surfactant for preventing agglomeration of nanoparticles, and are in such a state that aggregated nanoparticles easily form.

In the above-described respective processes, "ultrasonic processing" was performed by operating the ultrasonic vibrator at 30 kHz outside the resonance vibration frequency for 30 minutes. In the "ultrasonic resonance processing ", the ultrasonic vibrator was operated at a resonance frequency of 51 kHz and processed for 30 minutes. The irradiation conditions of the laser beam in the light pulverizing treatment were as follows: a wavelength of 1064 nm, a light intensity of 688 mJ / cm 2 per pulse laser beam, a spot diameter of the laser beam of 5 mm (irradiation area: 0.196 cm 2) FWHM 4., And treated for 30 minutes.

(Nonidet P-40: trade name Igapal CA-630, molecular weight of 602, critical micelle concentration of 0.29 mM) was used as a pretreatment for obtaining the particle diameter distribution of particles by a particle size distribution measuring apparatus in the present example, 100 占 퐇 was added to the treatment liquid, and the particle particle diameter distribution was measured under the condition that the re-aggregation of the nanoparticles was suppressed. The water temperature at the time of measurement was 25 ° C, which is room temperature.

4 is a graph showing the particle diameter distribution of platinum nanoparticles subjected to the respective treatments. In this graph, the axis of abscissas represents the particle diameter (탆) of platinum, and the axis of ordinates represents the volume of moles of the relative volume in terms of volume. The graphs A1 to A6 correspond to the processes (a) to (f), respectively.

In the graph of FIG. 4, when the graphs A1 and A2 are compared, it can be seen that the particle diameter distribution of platinum does not change only by ultrasonic treatment. In comparison between the graphs A2 and A3, since a large vibration acts on the particles in the graph A3 on which the ultrasonic resonance processing is performed, slight nanoparticle formation is observed.

In comparison between the graph A4 in which only the light pulverization process by the laser light irradiation is performed and the graphs A5 and A6 in which the ultrasonic wave process and the ultrasonic resonance process are performed simultaneously with the light pulverization process and the ultrasonic wave irradiation together with the laser light irradiation, It can be confirmed that the efficiency of combustion is increased.

On the graph A6 using ultrasonic irradiation by resonance vibration, since the vibration amplitude is larger than that of normal ultrasonic irradiation, the function of redispersing the aggregated nanoparticles is strong. As a result, the scattering loss of the laser light by the aggregated nanoparticles And the efficiency of the nanoparticles is particularly enhanced.

From the above, it was confirmed that when optical pulverization is performed in a state where aggregation of nanoparticles is likely to occur, it is effective in increasing the efficiency of nanoparticle formation by using ultrasonic irradiation together with laser light irradiation.

The method for producing a nanoparticle dispersion of the present invention is a method for efficiently pulverizing a material to be crushed to nano-sized particles by irradiating laser light for optical crushing of the liquid to be treated with ultrasonic waves for preventing coagulation , A dispersion in which nanoparticles are dispersed in the solvent can be produced.

Also, by preparing a mixed solution obtained by mixing the obtained nanoparticle dispersion liquid with base particles having an outer diameter larger than that of the nanoparticles, drying the mixed liquid by a spray drying method, and supporting the nanoparticles on the surface of the base particles, A particle-bearing powder can be produced.

The nanoparticle dispersion or nanoparticle-bearing powder obtained by the production method of the present invention can easily manifest the effects of each material such as antioxidative action, antibacterial action, deodorizing action and further anticancer activity, It is highly available.

1A, 1B, 1C, 1D ... Manufacturing device of nanoparticle dispersion
2… The liquid to be treated
3 ... Processing vessel
4… Water (solvent)
5 ... Raw material particles (crushed material)
10 ... Laser light source
11 ... Magnet Stick
12 ... Magnet stirrer
13 ... Thermostat
15 ... Control device
20, 21 ... Ultrasonic vibrator
25, 26 ... Ultrasonic vibrator drive
30 ... microphone
35, 35 ... Vibration amplitude measuring device
40 ... pipe
P ... Nanoparticle
C ... Base particle
Q ... Nano-particle-bearing powder

Claims (16)

A method of immersing a to-be-crushed material to be nanoparticles into a solvent of a treatment vessel,
A pulsed laser is applied to the material to be crushed, the crushed material is light-crushed with nano-sized particles, and the nanoparticles are dispersed in the solvent,
A method for producing a nanoparticle dispersion liquid in which ultrasonic waves are irradiated to the nanoparticle dispersion liquid to prevent agglomeration of the nanoparticles among the nanoparticle dispersion liquid,
Wherein the pulsed laser has a longer wavelength than an absorption band due to a unique electron transition of the material to be crushed.
The method according to claim 1,
And the surface of the material to be crushed is covered with a film having a laser absorbing function.
3. The method according to claim 1 or 2,
Wherein the material to be crushed is a plate-like material.
4. The method according to any one of claims 1 to 3,
Wherein the material to be crushed is in the form of particles.
5. The method according to any one of claims 1 to 4,
Wherein the solvent is water.
6. The method according to any one of claims 1 to 5,
Wherein a temperature adjusting mechanism for adjusting a temperature of the nanoparticle dispersion is provided in the processing vessel.
7. The method according to any one of claims 1 to 6,
A process liquid introduction pipe is formed outside the process container, the solvent and the material to be crushed are introduced into the process solution introduction pipe, the pulse laser is irradiated toward the process liquid introduction pipe, ≪ / RTI > wherein the nanoparticle dispersion is light pulverized into particles.
A nanoparticle dispersion prepared by the production method according to any one of claims 1 to 7,
Preparing a mixed liquid in which base particles having an outer diameter larger than that of the nanoparticles are mixed and drying the mixed liquid by a spray drying method to carry the nanoparticles on the surface of the base particles, Way.
A method of immersing a to-be-crushed material to be nanoparticles into a solvent of a treatment vessel,
A nanoparticle dispersion in which pulsed laser light is irradiated to the material to be crushed, the material to be crushed is light pulverized into nano-sized particles, and the nanoparticles are dispersed in the solvent,
A nanoparticle dispersion liquid obtained by irradiating ultrasonic waves to the nanoparticle dispersion liquid to prevent agglomeration of the nanoparticles among the nanoparticle dispersion liquid,
Wherein the pulsed laser has a longer wavelength than an absorption band due to a unique electron transition of the material to be crushed.
10. The method of claim 9,
Wherein the surface of the material to be crushed is covered with a coating having a laser absorbing function.
11. The method according to claim 9 or 10,
Characterized in that the material to be crushed is in the form of a plate.
12. The method according to any one of claims 9 to 11,
Wherein the material to be crushed is in the form of particles.
13. The method according to any one of claims 9 to 12,
Wherein the solvent is water.
14. The method according to any one of claims 9 to 13,
Wherein a temperature adjusting mechanism for adjusting a temperature of the nanoparticle dispersion is provided in the processing vessel.
15. The method according to any one of claims 9 to 14,
A process liquid introduction pipe is formed outside the process container, the solvent and the material to be crushed are introduced into the process solution introduction pipe, the pulse laser is irradiated toward the process liquid introduction pipe, Lt; RTI ID = 0.0 > nanoparticle < / RTI > dispersion.
16. The nanoparticle dispersion according to any one of claims 9 to 15,
Wherein the nano particles are supported on the surface of the base particles by preparing a mixed solution obtained by mixing base particles having an outer diameter larger than that of the nano particles and drying the mixed solution by a spray drying method, .

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