WO2017069250A1

WO2017069250A1 - Particle analysis device and particle analysis method

Info

Publication number: WO2017069250A1
Application number: PCT/JP2016/081301
Authority: WO
Inventors: 山口　哲司; 健太郎西方; かほる中山; 啓二郎櫻本
Original assignee: 株式会社堀場製作所
Priority date: 2015-10-23
Filing date: 2016-10-21
Publication date: 2017-04-27
Also published as: JP6726675B2; JPWO2017069250A1

Abstract

In order to be capable of measuring particle magnetization of particles and the characteristics of a plurality of particles, using one device, and in order to be capable of detailed particle analysis, the present invention comprises: a magnetization measurement unit comprising a magnetic field-formation mechanism and a magnetization calculation unit, said magnetic field-formation mechanism forming a magnetic field gradient relative to a dispersion medium including particles, and said magnetization calculation unit calculating the magnetization of said particles on the basis of the magnetophoretic velocity of the particles and the diameter of the particles; and a characteristics analysis unit that performs at least one out of particle diameter distribution measurement, zeta potential measurement, gel structure analysis, molecular weight measurement, elemental analysis, and shape analysis, performing same on particles in the dispersion medium and by using dynamic light scattering or static light scattering at a location where there is substantially no magnetic-field effect caused by the magnetic field-formation mechanism M.

Description

Particle analyzer and particle analysis method

The present invention relates to a particle analysis apparatus and particle analysis method for analyzing particles.

For example, in order to confirm whether or not the produced particles have desired characteristics, a particle analyzer as shown in Patent Document 1 is used. This particle analyzer is configured to irradiate a cell containing a dispersion medium in which particles are dispersed with a laser beam and measure the particle size distribution based on fluctuations in the intensity of the scattered light. .

JP 2010-78469 A

By the way, the inventor of the present application has reconsidered how to obtain more detailed and useful information about the physical properties of the particles with one particle analyzer. As a result, it has been found for the first time that the magnetic susceptibility of particles and other particle properties should be measured in one measuring device.

The present invention has been made as a result of intensive studies by the inventors of the present application, and is capable of measuring the characteristics of various particles together with the magnetic susceptibility of the particles with a single device, enabling detailed particle analysis. The purpose is to provide.

That is, the particle analyzer according to the present invention calculates the magnetic susceptibility of a particle based on a magnetic field forming mechanism that forms a magnetic field gradient with respect to the dispersion medium containing the particle, the magnetophoretic velocity of the particle, and the particle diameter of the particle. A magnetic susceptibility measurement unit comprising a magnetic susceptibility calculation unit, and a particle in the dispersion medium by a dynamic light scattering method or a static light scattering method at a location where there is substantially no magnetic field influence by the magnetic field formation mechanism. And a characteristic analysis unit that performs at least one of particle size distribution measurement, zeta potential measurement, gel structure analysis, molecular weight measurement, elemental analysis, and shape analysis by scattered light.

Further, the particle analysis method according to the present invention includes forming a magnetic field gradient with respect to a dispersion medium containing particles by a magnetic field forming mechanism, and determining the magnetic susceptibility of the particles based on the magnetophoretic velocity and the particle diameter of the particles. Calculating, particle size distribution measurement by dynamic light scattering method or static light scattering method, zeta potential measurement, gel in a place where there is substantially no magnetic field influence by the magnetic field formation mechanism for particles in the dispersion medium Performing at least one of structural analysis, molecular weight measurement, elemental analysis, and shape analysis by scattered light.

If this is the case, the magnetic susceptibility of the particles, the particle size distribution measurement by the dynamic light scattering method or the static light scattering method in a place where there is substantially no magnetic field influence by the magnetic field formation mechanism of the particles, zeta potential At least one measurement result of measurement, gel structure analysis, molecular weight measurement, elemental analysis, and shape analysis can be obtained with one particle analyzer. And it becomes possible to obtain the knowledge about the particle | grains which were not obtained conventionally by the combination of the magnetic susceptibility and the measurement result obtained by the said characteristic analysis unit.

In order for the user to easily understand the characteristics of the particle from the magnetic susceptibility and the measurement result of the characteristic unit, and to easily obtain the knowledge of the particle that was not conventional, the magnetic susceptibility measured by the magnetic susceptibility measurement unit and the characteristic What is necessary is just to further provide the measurement result display part which displays at least 1 of the measurement result measured by the analysis unit on the same screen.

In order to be able to accurately measure the magnetophoretic velocity of even minute particles and to obtain an accurate magnetic susceptibility, a laser light source that emits laser light to a cell containing the dispersion medium, and the dispersion medium A detector for detecting scattered light scattered by the particles therein, and a particle velocity calculation unit for calculating the velocity of the particles based on a change in the frequency of the scattered light of the laser light scattered by the particles, The magnetic susceptibility calculation unit is configured to calculate the magnetic susceptibility based on a magnetophoretic velocity that is a particle velocity calculated by the particle velocity calculation unit in a state where a magnetic field gradient is formed by the magnetic field forming mechanism. Anything can be used.

One specific embodiment for accurately measuring the magnetophoretic velocity with scattered light is one in which the particle velocity calculator is configured to calculate the velocity of particles based on the Doppler method. .

As a specific configuration for measuring the magnetophoretic velocity based on the Doppler method, the particle further includes a reference optical path through which laser light reaches the reference light without passing through the cell from the laser light source to the detector, A configuration in which the velocity calculation unit is configured to calculate the velocity of the particles based on the Doppler shift appearing in the interference light in which the scattered light detected by the detector and the reference light interfere with each other is exemplified.

As another aspect of calculating the magnetophoretic velocity based on the detected scattered light, the particle velocity calculation unit calculates the velocity of the particles based on the autocorrelation function of the intensity of the scattered light detected by the detector. The thing comprised as follows is mentioned.

In order to share the configuration related to the measurement of particle velocity between the magnetic susceptibility measurement unit and the characteristic analysis unit, and to be able to measure the magnetic susceptibility and zeta potential of the particle in a compact configuration, the characteristic analysis unit is An electric field forming mechanism that forms an electric field gradient with respect to the dispersion medium, and an electrophoretic velocity that is a velocity of particles calculated by the particle velocity calculating unit in a state where the electric field gradient is formed by the electric field forming mechanism. And a zeta potential calculator that calculates the zeta potential.

In order to allow the magnetic susceptibility measurement unit and the characteristic analysis unit to share the configuration related to the measurement of the particle diameter of the particles, in order to obtain an accurate value even for a minute particle, the characteristic analysis unit Is further provided with a particle size distribution calculation unit for calculating the particle size distribution of the particles in the dispersion medium by a dynamic light scattering method or a static light scattering method based on the intensity signal of the scattered light obtained from the particles, The magnetic susceptibility calculation unit may be configured to calculate the magnetic susceptibility of particles based on the particle size distribution calculated by the particle size distribution calculation unit.

Based on the magnetic susceptibility obtained by the magnetic susceptibility measurement unit, in order to enable the characteristic analysis unit to measure the characteristics of the particles that could not be obtained by a conventional apparatus, the characteristic analysis unit can obtain the Raman obtained from the particles. Based on the spectrum of scattered light or the spectrum of fluorescence, the elemental analysis unit for performing elemental analysis of the particles, the result of elemental analysis of the particles by the elemental analysis unit, and the magnetic susceptibility of the particles calculated by the magnetic susceptibility calculation unit And a surface analysis unit that analyzes an organic substance that forms the surface of the particle.

In order to obtain the properties of the gel in a multifaceted manner in combination with the magnetic susceptibility, the dispersion medium and the particle group, the filler group, or the fibrous substance form a gel structure, and the characteristic analysis unit includes What is necessary is just to further include a gel structure analysis unit for calculating the interstitial distance of the gel structure or the hardness of the gel based on the intensity signal of the obtained scattered light. Here, the gel means a group of particles such as colloidal particles, a group of fillers, and a fibrous substance that form a framework structure, and a liquid such as moisture is held inside the framework structure.

In order to enable, for example, the qualitative determination of particles more accurately from the combination of the magnetic susceptibility and molecular weight of the particles, the characteristic analysis unit calculates the molecular weight of the particles based on the intensity signal of the scattered light obtained from the particles. What is necessary is just to further provide the calculation part.

For example, in order to obtain a more realistic particle characteristic in consideration of the surface shape and magnetic susceptibility of the particle, the characteristic analysis unit uses the scattered light intensity signal at a plurality of scattering angles obtained from the particle. Based on this, any shape analysis unit that analyzes the shape of the particles may be used.

Thus, according to the particle analyzer according to the present invention, the particle susceptibility, particle size distribution measurement by dynamic light scattering method or static light scattering method, zeta potential measurement, gel structure analysis, molecular weight in one device Since at least one measurement result of measurement, elemental analysis, and shape analysis can be obtained, it is possible to obtain detailed characteristics of particles that could not be obtained conventionally.

The schematic diagram which shows the particle | grain analyzer which concerns on 1st Embodiment of this invention. The schematic diagram shown about the structure of the particle | grain analyzer of 1st Embodiment at the time of a magnetophoretic velocity measurement, and the irradiation point of a laser beam. The schematic diagram shown about the structure of the particle analyzer of 1st Embodiment at the time of particle diameter measurement, and the irradiation point of a laser beam. The typical functional block diagram of the particle analyzer of a 1st embodiment. The schematic diagram which shows the display form of the measurement result in the particle | grain analyzer of 1st Embodiment. The schematic diagram which shows the 1st modification of the particle | grain analyzer of 1st Embodiment. The schematic diagram which shows the 2nd modification of the particle | grain analyzer of 1st Embodiment. The schematic diagram which shows the particle | grain analyzer which concerns on 2nd Embodiment of this invention. The typical functional block diagram of the particle | grain analyzer of 2nd Embodiment. The schematic diagram which shows the display form of the measurement result in the particle | grain analyzer of 2nd Embodiment. The schematic diagram which shows the particle | grain analyzer which concerns on 3rd Embodiment of this invention.

DESCRIPTION OF SYMBOLS 100 ... Particle analyzer I ... Irradiation optical system IL ... Laser light source D ... Light receiving optical system D1 ... Transmitted light detector D2 ... Front detector D3 ... Side detector D4: Rear detector D5: Video camera D6: Rotation detector COM ... Arithmetic mechanism M ... Magnetic field forming mechanism E ... Electric field forming mechanism 1 ... Characteristic analysis unit 11・ Particle size distribution calculation unit 12 ・・・ Zeta potential calculation unit 13 ・・・ Molecular weight calculation unit 14 ・・・ Gel structure analysis unit 15 ・・・ Element analysis unit 16 ・・・ Surface analysis unit 17 ・・・ Shape analysis unit 2 ... Magnetic susceptibility measurement unit 21 ... Magnetic susceptibility calculator R ... Reference optical path R1 ... First beam splitter R2 ... Second beam splitter R3 ... Mirror R4 ... Modulator V ..Particle velocity calculation part P ... Measurement Result display area

The particle analyzer 100 according to the first embodiment of the present invention will be described with reference to FIGS. In the following, the horizontal direction in FIG. 1 is defined as the X axis, the vertical direction in the paper is defined as the Y axis, and the direction perpendicular to the paper surface is defined as the Z axis.

The particle analyzer 100 of the first embodiment irradiates particles dispersed in a dispersion medium with laser light, and based on the scattered light of the laser light scattered by the particles, the particle size distribution of the particles, the zeta potential, It measures molecular weight, gel structure, and magnetic susceptibility. That is, the particle analyzer 100 includes a characteristic analysis unit 1 that measures particle size distribution, zeta potential, molecular weight, and gel structure of particles, and a magnetic susceptibility measurement unit 2 that measures the magnetic susceptibility of particles.

As shown in FIGS. 1 to 3, the particle analyzer 100 includes, as a hardware configuration, a cell C in which the dispersion medium is accommodated, an irradiation optical system I that irradiates the cell C with laser light, and The reference light path R for obtaining the reference light, the light receiving optical system D that receives the scattered light scattered by the particles in the cell C or the laser light, and the intensity of the scattered light obtained by the light receiving optical system D And a calculation mechanism COM for performing various calculations based on the calculation. The cell C, the irradiation optical system I, the reference optical path R, the light receiving optical system D, and the calculation mechanism COM are configured to be shared by the characteristic analysis unit 1 and the magnetic susceptibility measurement unit 2. Further, the characteristic analysis unit 1 includes an electric field forming mechanism E that forms an electric field gradient with respect to the dispersion medium in the cell C. The magnetic susceptibility measurement unit 2 includes a magnetic field forming mechanism M that forms a magnetic field gradient with respect to the dispersion medium in the cell C.

Each part will be explained.

The cell C is a transparent cell formed of glass, quartz, resin, or the like in which a dispersion medium is accommodated, as shown in FIGS. As shown in FIG. 1, the cell C has a substantially square cross section. The shape of the cell C is not limited to that shown in the figure, and may be, for example, a cylindrical shape. 2 and 3 are a perspective view and a view when the cell C is viewed from the irradiation direction side of the laser beam. As shown in FIGS. 2 and 3, the cell C is in the depth direction of FIG. It is a thing of the substantially rectangular parallelepiped shape extended in. As shown in FIG. 1, the electric field forming mechanism E and the magnetic field forming mechanism M are provided inside or around the cell C. In FIG. 2 and FIG. 3, the electric field forming mechanism E is not shown.

Further, the cell C is configured so that the irradiation point IP of the laser light emitted from the irradiation optical system I can be appropriately changed by a driving mechanism (not shown). More specifically, the drive mechanism is configured such that the irradiation point IP of the laser beam in the cell C can be changed at least in the magnetic field gradient as shown in FIG. 2 or outside the magnetic field gradient as shown in FIG. It is. As will be described later, in order to calculate the magnetophoretic velocity of particles and the magnetic susceptibility of particles for data obtained from scattered light, reflected light, and transmitted light obtained when the laser light irradiation point IP is in a magnetic field gradient. Used. Further, data obtained from scattered light obtained at a location where the laser beam irradiation point IP is outside the magnetic field gradient and the magnetic field forming mechanism E is substantially free from the magnetic field is used to calculate at least the particle diameter. . Here, “substantially no magnetic field influence” refers to a state in which no magnetic force acts on the particles, or only a magnetic force that affects only the measurement error in calculating the particle diameter.

The irradiation optical system I includes the laser light source IL shown in FIG. 1 and a lens (not shown). The focusing position of the laser in the cell C can be changed by moving the lens. For example, the irradiation optical system I may further include a polarizing filter that allows only specific polarized light to pass therethrough.

The light receiving optical system D is composed of four detectors provided apart from the cell C. That is, the light receiving optical system D includes a transmitted light detector D1, a front detector D2, a side detector D3, and a rear detector D4.

The transmitted light detector D1 detects transmitted light transmitted through the cell C, which is a photodiode. Based on this transmitted light, for example, the concentration of particles in the dispersion medium is measured. In addition, in the functional block diagram to be described later, the description of the calculation unit relating to concentration calculation is omitted, but the concentration is also displayed as one of the measurement results.

The forward detector D2 uses a photomultiplier tube and detects forward scattered light emitted from the cell C. A zeta potential is calculated based on the forward scattered light. Here, the position of the front detector D2 can be changed by rotating in the XY plane around the cell C. That is, an angle θ formed by a straight line connecting the cell C and the transmitted light detector D1 and a straight line connecting the cell C and the front detector D2 is adjusted to be an angle suitable for detecting scattered light. It is possible.

The side detector D3 also uses a photomultiplier tube and detects side scattered light emitted from the cell C. When the concentration of particles in the dispersion medium is lower than a predetermined concentration, the particle size distribution is calculated based on the side scattered light. Further, the molecular weight is calculated based on the side scattered light.

The back detector D4 also uses a photomultiplier tube and detects backscattered light emitted from the cell C. When the concentration of particles in the dispersion medium is higher than a predetermined concentration, the particle size distribution is calculated based on the backscattered light.

As shown in FIG. 1, the reference light path R is configured such that laser light reaches as reference light from the laser light source IL to the front detector D2 without passing through the cell C. That is, the reference optical path R includes a first beam splitter R1 provided between the laser light source IL and the cell C, and a second beam splitter provided between the cell C and the front detector D2. R2 and a mirror R3 and a modulator R4 for guiding a part of the laser beam reflected by the first beam splitter R1 to the second beam splitter R2. The forward scattered light and the reference light after passing through the second beam splitter R2 become interference light, and the Doppler shift is detected in the forward detector D2.

The electric field forming mechanism E is composed of two parallel plate electrodes provided in the cell C. A predetermined voltage is applied between these parallel plate electrodes to form an electric field gradient in the Y-axis direction, and the particles are electrophoresed in the Y-axis direction. The electric field forming mechanism E is not limited to the parallel plate electrode, and may be a pair of cylindrical or semi-cylindrical electrodes, for example.

The magnetic field forming mechanism M uses an electromagnet M2 provided so as to be sandwiched outside the cell C. A magnetic field gradient is formed in the X-axis direction or the Z-axis direction by the magnetic field forming mechanism M, and the particles are magnetophoresed in the X-axis direction or the Z-axis direction. That is, the direction of particle movement is different between electrophoresis and magnetophoresis. Here, the magnetic field gradient refers to a magnetic field gradient formed at a portion where the density of magnetic lines of force changes between a pair of magnetic poles. For example, in the first embodiment, it refers to a magnetic field portion formed at the outer edge portion of the pair of electromagnets M2. The place where the magnetic field gradient is formed in the cell C can be determined by the size of the electromagnet M2 and the position with respect to the cell C.

The magnetic field forming mechanism M includes a pair of electromagnets M2 and a holding block M1 that holds the electromagnets M2. The holding block M1 is formed of a non-magnetic material and has a portion covering the upper and lower surfaces and one side surface of the cell C as shown in FIG. An electromagnet M2 is attached to a portion of the holding block M1 that covers the upper and lower surfaces of the cell C, and the N pole and the S pole are formed to face each other in the vertical direction. An opening for allowing the laser beam to pass is provided in a portion covering the side surface of the cell C of the holding block M1. The holding block M1 is configured to be movable in the X-axis direction, which is the left-right direction in FIG. That is, when measuring the magnetophoretic velocity by forming a magnetic field gradient with respect to the cell C, the holding block M1 moves to an operating position where the electromagnet M2 is disposed above and below the cell C. On the other hand, when it is not necessary to form a magnetic field, the holding block M1 moves to the retracted position as shown by the dotted line in FIG. Further, the electromagnet M2 is not energized at the retracted position. With this configuration, even if the holding block M1 itself is magnetized by repeating energization of the electromagnetic translation M2, the holding block M1 is moved to the retracted position except when the magnetophoretic velocity is measured. Thus, a magnetic field can be substantially not formed in the cell C. In the case where the electromagnet M2 is used for the magnetic field forming mechanism M, the energization may be performed only when the magnetophoretic velocity is measured, and the holding block M1 may be always fixed at the operating position. In the case where a permanent magnet is used for the magnetic field forming mechanism M, the state in which the magnetic field gradient is formed in the cell C is formed by moving the holding block M1 between the operating position and the retracted position. You may make it switch the state which is not performed.

The calculation mechanism COM is a so-called computer including a CPU, a memory, input / output means, an A / D / D / A converter, and the like. A program for the particle analyzer 100 stored in the memory is executed, and a software part is realized in the configuration of the characteristic analysis unit 1 and the magnetic susceptibility measurement unit 2 by cooperating with various devices. That is, the calculation mechanism COM functions as a software configuration of the characteristic analysis unit 1 as shown in FIG. 4 as a particle size distribution calculation unit 11, a zeta potential calculation unit 12, a molecular weight calculation unit 13, and a gel structure analysis unit 14. Demonstrate. In addition, the calculation mechanism COM exhibits a function as the magnetic susceptibility calculation unit 21 as a software configuration of the magnetic susceptibility measurement unit 2. Further, as the software configuration shared by the characteristic analysis unit 1 and the magnetic susceptibility measurement unit 2, the functions as the particle velocity calculation unit V and the measurement result display unit P are exhibited.

Each part will be explained.

The particle size distribution calculating unit 11 is based on the intensity signal of scattered light obtained from the side detector D3 or the rear detector D4, and the particle size distribution of the particles in the dispersion medium by a dynamic light scattering method. Is calculated. Here, an autocorrelation function is obtained by the photon correlation method, and a particle diffusion coefficient is calculated from the autocorrelation function. The particle diameter is obtained from the diffusion coefficient and the Stokes-Einstein equation. Further, as shown in FIG. 3, the particle size distribution calculating unit 11 is configured to calculate the particle size based on the intensity of scattered light obtained when laser light is irradiated outside the magnetic field gradient. is there.

The particle velocity calculation unit V calculates the velocity of particles based on a change in the frequency of scattered light generated when laser light is scattered by particles. In the first embodiment, the particle velocity is calculated by a laser Doppler velocimeter based on the Doppler method. More specifically, the velocity of the particles is calculated based on the Doppler shift that appears in the interference light obtained by the interference between the scattered light detected by the front detector D2 and the reference light. Here, as shown in FIG. 2, when the irradiation point of the laser beam in the cell C is in a magnetic field gradient, the particle velocity calculated by the particle velocity calculator V corresponds to the magnetophoretic velocity. Further, the velocity of the particles calculated in a state where the holding block M1 is in the retracted position and there is no magnetic field gradient in the cell C and an electric field gradient is formed by the electric field forming mechanism E corresponds to the electrophoresis velocity.

The zeta potential calculation unit 12 shown in FIG. 4 is configured to calculate the zeta potential based on the electrophoretic velocity or particle mobility calculated by the particle velocity calculation unit V.

The molecular weight calculation unit 13 is configured to calculate the molecular weight of the particles based on the intensity signal of the side scattered light obtained from the side detector D3 by measurement by the static light scattering method. Here, the absolute molecular weight of the particles is calculated using the Debye plot.

The gel structure analysis unit 14 calculates the interstitial distance of the gel structure or the hardness of the gel based on the intensity signal of the scattered light obtained from the particles. Here, the interstitial distance is calculated using the fact that the pattern of the autocorrelation function of the intensity of scattered light changes according to the interstitial distance of the gel.

The magnetic susceptibility calculator 21 is configured to calculate the magnetic susceptibility based on the particle magnetophoretic velocity calculated by the particle velocity calculator V and the particle size distribution calculated by the particle size distribution calculator 11. It is. That is, the light receiving optical system D and the particle velocity calculating unit V are commonly used for calculating the magnetic susceptibility and the zeta potential. For the particle size, a representative value such as an average value of the particle size distribution is used. Thus, the particle velocity and particle diameter are shared between the characteristic analysis unit 1 and the magnetic susceptibility measurement unit 2, and the magnetic susceptibility measurement unit 2 itself measures for measuring the magnetophoretic velocity and particle diameter. The mechanism is omitted.

As shown in FIG. 5, the measurement result display unit P displays at least one of the magnetic susceptibility measured by the magnetic susceptibility measurement unit 2 and the measurement result measured by the characteristic analysis unit 1 on the same screen. It is constituted as follows. Here, the same screen means that the same screen is displayed on the display, for example. In other words, each measurement result is not displayed separately on an individual page, but is displayed on the same page. In the first embodiment, as shown in FIG. 5, at least six graphs are displayed on the same page. More specifically, the horizontal axis is the particle diameter, the vertical axis is the particle diameter-susceptibility graph with the magnetic susceptibility at that particle diameter, the horizontal axis is the particle diameter, and the vertical axis is the frequency of appearance of the particle diameter. The particle size-frequency graph, the zeta potential on the horizontal axis, the zeta potential-frequency graph with the vertical axis representing the frequency of appearance of the zeta potential, the horizontal axis represents the concentration, and the vertical axis is output from the front detector D2 at that concentration. Concentration-intensity graph of the intensity of light to be emitted, the horizontal axis represents the aspect ratio of particles calculated from the extinction ratio of S-wave and P-wave of laser light, and the vertical axis represents the frequency of appearance of particles having the aspect ratio. The molecular weight-frequency graph and the lattice interval-frequency graph with the horizontal axis output from the gel structure analysis unit 14 and the vertical axis with the frequency of appearance of the lattice interval are displayed on the same page.

By displaying a plurality of graphs in this way, it is possible to confirm not only the magnetic susceptibility but also the characteristics of various particles. For example, as shown in FIG. 5, when there is a discrepancy such as a case where the magnetic susceptibility has only one peak and there are two peaks in the particle size distribution, impurities are mixed in the particle manufacturing process. It becomes possible to discover that there is a possibility. In addition, when the magnetic susceptibility of the particle group is not controlled to a desired value, for example, an extremely large particle is generated due to the aggregation of magnetic metal, etc., particle size distribution, zeta potential, etc. It is possible to investigate the cause by confirming the other measurement results of the above together with the measurement result of the magnetic susceptibility.

According to the particle analyzer 100 of the first embodiment configured as described above, the particle diameter, zeta potential, molecular weight, and gel structure can be measured together with the magnetic susceptibility by one device and one cell C. In addition, since other measurement results are displayed together with the magnetic susceptibility on the same screen, each result can be recognized at a glance, and the user can understand more detailed information on the characteristics of particles than before. .

Further, since the particle diameter and magnetophoretic velocity necessary for calculating the magnetic susceptibility are calculated by a mechanism shared with the configuration of the characteristic analysis unit 1, the configuration of the entire apparatus can be simplified and made compact.

Further, the particle diameter is calculated by the dynamic light scattering method based on the scattered light obtained in the state where the laser beam is irradiated to the region where the magnetic field gradient is not formed, so that the particle diameter is smaller than 1 μm. Also, the particle diameter can be calculated accurately. This is because the particle diameter is calculated reflecting the three-dimensional Brownian motion.

Therefore, the accuracy of the magnetic susceptibility itself can be increased by the cooperation of the characteristic analysis unit 1 and the magnetic susceptibility measurement unit 2.

Next, a modification of the first embodiment will be described.

The particle size may be calculated based on the static light scattering method instead of the dynamic light scattering method. Further, when the holding block M1 is made of a material that does not have magnetism, the position of the holding block M1 is fixed at the operating position, and the particles obtained from the state in which the magnetic field forming mechanism E is not energized. The particle size distribution calculating unit 11 may be configured to calculate the particle size based on the scattered light.

As shown in FIGS. 6A and 6B, the direction of the magnetic field formed by the magnetic field forming mechanism M is reversed every predetermined period to reverse the direction of the magnetic force acting on the particles, and the magnetophoretic velocity is measured. You may comprise so that it can do. More specifically, when a permanent magnet is used as the magnet M2, the holding block M1 may be configured to be rotatable about the center of the cell C as a rotation axis. Thus, by changing the moving direction by the magnetic force of the particles and performing the measurement a plurality of times, it is possible to reliably capture the change in the frequency of the scattered light. When an electromagnet is used for the magnetic field forming mechanism M, the energization direction is reversed every predetermined period, so that the reversal of the direction of the magnetic force is repeated and the magnetophoretic velocity in both directions is measured a plurality of times. Also good.

Further, in order to match the direction of particle magnetophoresis and electrophoresis so that the measurement error due to the difference in the moving direction can be reduced, the magnetic field forming mechanism M as shown in FIGS. The direction of the magnetic force generated by the magnetic field gradient formed by the electric field forming mechanism E and the direction of the force generated by the electric field forming mechanism E may coincide with each other in the Z-axis direction, for example. In other words, the opposing direction of the pair of magnets M2 and the opposing direction of the pair of electrode plates may be arranged so as to intersect each other.

The particle velocity calculation unit V may calculate the particle velocity based on the change in the frequency of the scattered light by other methods than the Doppler method. Specifically, the diffusion coefficient may be calculated from the autocorrelation function of the scattered light intensity, and the velocity of the particles may be calculated from the diffusion coefficient.

In order to change the irradiation point IP of the laser beam to the cell C, the cell C itself may not be moved, but a part or all of the optical system itself of the particle analyzer 100 may be configured to be movable.

Next, the particle analyzer 100 of the second embodiment will be described with reference to FIGS. Note that members corresponding to those described in the first embodiment are denoted by the same reference numerals.

The particle analyzer 100 according to the second embodiment is a rotation detector D6 in which the light receiving optical system D is configured to be rotatable in a plane centered on the cell C as shown in FIG. Can be detected by one detector. Here, the rotation detector D6 is replaced with a detector for measuring Raman light or fluorescence. Further, a video camera D5 is provided at the position of the transmitted light detector D1 in the first embodiment. As in the first embodiment, the magnetic field forming mechanism M is provided outside the cell C.

Further, as shown in FIG. 9, the calculation mechanism COM includes a particle size distribution calculation unit 11, a particle velocity calculation unit V, an element analysis unit 15, a shape analysis unit 17, and a surface analysis unit 16 which are software configurations of the characteristic analysis unit 1. It is comprised so that the function as may be demonstrated. The calculation mechanism COM is configured to exhibit a function as a magnetic susceptibility calculation unit 21 that is a software configuration of the magnetic susceptibility measurement unit 2. In addition, the calculation mechanism COM also functions as a measurement result display unit P that displays the magnetic susceptibility and various measurement results on the same screen.

Each part will be explained.

The magnetic susceptibility calculation unit 21 performs magnetization based on the particle diameter and magnetophoretic velocity calculated by the particle size distribution calculation unit 11 and the particle velocity calculation unit V based on a still image or a moving image captured by the video camera D5. The rate is calculated.

That is, the particle size distribution calculating unit 11 is configured to calculate the particle size by analyzing the still image captured by the video camera D5. Here, the boundary between the particle and the background in the still image is detected by the difference in luminance, and the particle diameter is calculated from the area inside the boundary.

The particle velocity calculation unit V calculates the particle velocity based on the moving image captured by the video camera D5. More specifically, in the state where a magnetic field gradient is formed in the cell C by the magnetic field forming mechanism M, the movement of particles in the Z-axis direction, which is the direction of the magnetic force, is extracted from the moving image, and the movement per number of frames. The magnetophoretic velocity is calculated from the distance.

The element analysis unit 15 performs elemental analysis of particles based on the Raman scattered light or fluorescence spectrum obtained by the rotation detector D6. That is, the element contained in the particle is specified by comparing the peak of the spectrum of Raman scattered light or fluorescence with the peak of various elements.

The surface analysis unit 16 analyzes the organic matter forming the surface of the particle based on the elemental analysis result of the particle by the elemental analysis unit 15 and the magnetic susceptibility of the particle calculated by the magnetic susceptibility calculation unit 21. It is configured. For example, when the surface of a base material having a spherical particle is coated with an organic material, the magnetic susceptibility calculated by the magnetic susceptibility calculation unit 21 is obtained by weighted average of the magnetic susceptibility of the base material and the magnetic susceptibility of the coating by the composition ratio. It is the value. Moreover, if the element which comprises particle | grains, and its ratio are known from an elemental analysis result, the composition ratio of a base material and a coating can also be known. For these reasons, the surface analysis unit 16 calculates the coating thickness based on the elemental analysis results, the magnetic susceptibility, and the particle diameter calculated by the particle size distribution calculation unit 11.

The shape analysis unit 17 analyzes the shape of particles based on the intensity signals of scattered light at a plurality of scattering angles obtained by the rotation detector D6. Here, for example, the aspect ratio is analyzed based on the intensity of scattered light for each scattering angle.

As shown in FIG. 10, the measurement result display unit P displays the appearance frequency of the film thickness for each particle diameter, the magnetic susceptibility for each particle diameter, the aspect ratio of the particles, the Raman spectrum, and the fluorescence spectrum on the same screen. It is configured.

With the particle analyzer 100 according to the second embodiment configured as described above, it is possible to obtain a coating thickness of a particle coating that has not been known in the past by combining the magnetic susceptibility and the elemental analysis result.

Furthermore, since the shape of the particles can be obtained together with the film thickness, it is possible to evaluate not only the uniformity of the particle diameter but also the uniformity of the shape and the uniformity of the composition.

Next, a modification of the particle analyzer 100 of the second embodiment will be described.

The particle size distribution calculating unit 11 extracts a one-dimensional or two-dimensional Brownian motion of particles based on the moving image of the video camera D5, calculates a diffusion coefficient based on the speed of the Brownian motion, May be calculated. Note that when the particles are imaged by the video camera D5, the cell C may be illuminated with incoherent light such as a halogen light source instead of the laser light source IL. The video camera D5 may capture not only transmitted light but also reflected light and scattered light to acquire an image.

In addition, the element analysis unit 15 may perform element analysis based on a fluorescence spectrum.

The surface analysis unit 16 may calculate characteristics other than the film thickness based on the elemental analysis result and the magnetic susceptibility.

Next, the particle analyzer 100 of the third embodiment will be described. In addition, the same code | symbol shall be attached | subjected to the member corresponding to the member demonstrated by the said embodiment.

The particle analyzer 100 according to the third embodiment includes a magnetic field forming mechanism M that forms a magnetic field gradient with respect to a dispersion medium containing particles as shown in FIG. 11, and based on the magnetophoretic velocity of particles and the particle diameter of particles. A magnetic susceptibility measuring unit 2 comprising a magnetic susceptibility calculating unit 21 for calculating the magnetic susceptibility of particles, and a dynamic light scattering method or static light scattering at a location where there is substantially no magnetic field effect by the magnetic field forming mechanism M. And a characteristic analysis unit 1 that performs only particle size distribution measurement by the method.

The characteristic analysis unit 1 includes a first laser light source IL1 that emits laser light to a portion of the cell C where a magnetic field gradient is not formed by the magnetic field forming mechanism M, and the first laser light source IL1 in the cell C. A first detector D21 that detects scattered light obtained by scattering the emitted laser light by particles, and a particle size distribution by a dynamic light scattering method or a static light scattering method based on the output of the first detector D21. A particle size distribution calculating unit 11 for calculating is provided.

On the other hand, the magnetic susceptibility measurement unit 2 includes a second laser light source IL2 that emits laser light to a portion of the cell C where a magnetic field gradient is formed by the magnetic field forming mechanism M, and the second laser light source in the cell C. A second detector D22 for detecting scattered light obtained by scattering the laser light emitted from IL2 by particles; a particle velocity calculating unit V for calculating a magnetophoretic velocity of particles based on the output of the second detector D22; And a magnetic susceptibility calculation unit 21 that calculates the magnetic susceptibility of particles based on the magnetophoretic velocity calculated by the particle velocity calculation unit V and the particle diameter of the particles calculated by the particle size distribution calculation unit 11. is there.

Such a particle analyzer 100 according to the third embodiment can obtain an accurate value even when the particle diameter is small while having a simple configuration, and thus an accurate magnetic susceptibility can be obtained.

Other embodiments will be described.

The characteristic analysis unit 1 uses the dynamic light scattering method or the static light scattering method, the zeta potential measurement for the particles in the dispersion medium at a place where there is substantially no magnetic field influence by the magnetic field formation mechanism. It is sufficient to perform at least one of gel structure analysis, molecular weight measurement, elemental analysis, and shape analysis by scattered light. If it is such, it becomes possible to know various characteristics of particles better by combining with magnetic susceptibility.

The irradiation optical system I and the light receiving optical system D are not limited to those shown in each embodiment. For example, detectors that are not necessary in the light receiving optical system D in accordance with the measurement and analysis performed in the characteristic analysis unit 1 may be omitted.

The laser light source IL, the various detectors, the particle velocity calculation unit, and the measurement result display unit P may constitute either the characteristic analysis unit 1 or the magnetic susceptibility measurement unit 2. The characteristic analysis unit 1 and the magnetic susceptibility measurement unit 2 may be elements constituting the particle analyzer 100 independently of each other.

The particle analyzer 100 further has an X-ray analysis mechanism including an X-ray tube, an X-ray, and a fluorescent X-ray detector, so that element analysis can be performed even if the particles in the dispersion medium are inorganic. .

The particle analyzer 100 of the present invention may be configured to perform all the measurements shown in the first and second embodiments and display all the measurement results shown in FIGS. 5 and 10 on the same screen. Good.

In addition, various combinations and modifications of the embodiments may be performed without departing from the spirit of the present invention.

According to the particle analyzer according to the present invention, the characteristics of a large number of particles can be measured together with the magnetic susceptibility of the particles with a single device, and detailed particle analysis becomes possible.

Claims

Magnetic susceptibility comprising: a magnetic field forming mechanism that forms a magnetic field gradient for a dispersion medium containing particles; and a magnetic susceptibility calculator that calculates the magnetic susceptibility of the particles based on the magnetophoretic velocity of the particles and the particle diameter of the particles A measurement unit;
For particles in the dispersion medium, particle size distribution measurement, zeta potential measurement, gel structure analysis, molecular weight measurement by a dynamic light scattering method or a static light scattering method at a place where there is substantially no magnetic field effect by the magnetic field formation mechanism. And a characteristic analysis unit that performs at least one of elemental analysis and shape analysis by scattered light.
2. The particle analyzer according to claim 1, further comprising a measurement result display unit that displays at least one of the magnetic susceptibility measured by the magnetic susceptibility measurement unit and the measurement result measured by the characteristic analysis unit on the same screen. .
A laser light source for emitting laser light to a cell containing a dispersion medium;
A detector for detecting scattered light scattered by particles in the dispersion medium;
A particle velocity calculator that calculates the velocity of the particles based on the change in the frequency of the scattered light of the laser light scattered by the particles, and
The magnetic susceptibility calculation unit is configured to calculate the magnetic susceptibility based on a magnetophoretic velocity that is a particle velocity calculated by the particle velocity calculation unit in a state where a magnetic field gradient is formed by the magnetic field forming mechanism. The particle analyzer according to claim 1.
The particle analyzer according to claim 3, wherein the particle velocity calculation unit is configured to calculate a particle velocity based on a Doppler method.
A reference light path through which the laser light reaches the reference light without passing through the cell from the laser light source to the detector;
The particle analysis according to claim 3, wherein the particle velocity calculation unit is configured to calculate a particle velocity based on a Doppler shift appearing in interference light in which scattered light detected by the detector and reference light interfere with each other. apparatus.
4. The particle analyzer according to claim 3, wherein the particle velocity calculation unit is configured to calculate a particle velocity based on an autocorrelation function of the intensity of scattered light detected by the detector.
The characteristic analysis unit comprises:
An electric field forming mechanism for forming an electric field gradient with respect to the dispersion medium;
A zeta potential calculation unit that calculates a zeta potential based on an electrophoretic velocity that is a velocity of particles calculated by the particle velocity calculation unit in a state where an electric field gradient is formed by the electric field forming mechanism. 4. The particle analyzer according to 3.
The characteristic analysis unit comprises:
Based on the intensity signal of the scattered light obtained from the particles, further comprising a particle size distribution calculating unit for calculating the particle size distribution of the particles in the dispersion medium by a dynamic light scattering method or a static light scattering method,
The particle analyzer according to claim 1, wherein the magnetic susceptibility calculation unit is configured to calculate the magnetic susceptibility of particles based on the particle size distribution calculated by the particle size distribution calculation unit.
An element analysis unit that performs elemental analysis of particles based on a spectrum of Raman scattered light obtained from the particles or a spectrum of fluorescence;
The surface analysis part which analyzes the organic substance which forms the surface of particles based on the elemental analysis result of the particles by the element analysis part, and the magnetic susceptibility of the particles calculated by the magnetic susceptibility calculation part 2. The particle analyzer according to 1.
The dispersion medium and the particle group have a gel structure,
The characteristic analysis unit comprises:
The particle analyzer according to claim 1, further comprising a gel structure analysis unit that calculates an interstitial distance of the gel structure or a gel hardness based on an intensity signal of scattered light obtained from the particles.
The characteristic analysis unit comprises:
The particle analyzer according to claim 1, further comprising a molecular weight calculator that calculates the molecular weight of the particle based on an intensity signal of scattered light obtained from the particle.
The characteristic analysis unit comprises:
The particle analyzer according to claim 1, further comprising a shape analysis unit that analyzes the shape of the particle based on intensity signals of scattered light at a plurality of scattering angles obtained from the particle.
Forming a magnetic field gradient for the dispersion medium containing particles by a magnetic field forming mechanism;
Calculating the magnetic susceptibility of the particle based on the magnetophoretic velocity of the particle and the particle diameter of the particle;
For particles in the dispersion medium, particle size distribution measurement, zeta potential measurement, gel structure analysis, molecular weight measurement by a dynamic light scattering method or a static light scattering method at a place where there is substantially no magnetic field effect by the magnetic field formation mechanism. A particle analysis method comprising: performing at least one of element analysis and shape analysis using scattered light.