Apparatus, program, and measurement method

Abstract

To provide a device, a program, and a measurement method capable of measuring characteristics of a sample with high accuracy and / or under various measurement conditions.SOLUTION: A device 100 for measuring characteristics of a liquid includes a placement surface 110a on which a liquid sample S is placed, a facing surface 110a that faces the placement surface 110a and is movable relative to the placement surface 110a in a direction substantially parallel to a normal line n of the placement surface 120a, and an imaging unit 130 that images a region sandwiched between the placement surface 110a and the facing surface 120a from a direction substantially perpendicular to the normal line n of the placement surface 110a.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an apparatus, a program, and a measurement method for measuring the properties of a sample, particularly a liquid sample. [Background technology]

[0002] Rheometers that measure the extensional strain of a liquid sample are used as devices for measuring the rheological properties of a liquid sample.

[0003] For example, Patent Document 1 discloses a method for measuring the extensional rheological properties of a fluid by observing capillary rupture after instantaneously extending the fluid between a pair of plates. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] U.S. Patent No. 6,711,941 Summary of the Invention [Problem to be solved by the invention]

[0005] However, existing devices, including the device described in Patent Document 1, still have problems, such as insufficient measurement accuracy and limited measurement conditions. For example, the device described in Patent Document 1 measures the extensional rheological properties of a fluid using the surface tension of the sample, which is obtained separately, and therefore has limited accuracy when measuring samples that are not Newtonian fluids.

[0006] The present invention has been made in consideration of the above-mentioned problems, and aims to provide an apparatus, a program, and a measurement method that can measure the characteristics of a sample with high accuracy and / or under various measurement conditions. [Means for solving the problem]

[0007] One aspect of the present disclosure provides an apparatus for measuring the characteristics of a liquid, comprising: a placement surface for placing a liquid sample; an opposing surface facing the placement surface and movable relative to the placement surface in a direction approximately parallel to the normal to the placement surface; and an imaging unit that images an area sandwiched between the placement surface and the opposing surface from a direction approximately perpendicular to the normal to the placement surface.

[0008] Since this device has an imaging unit that images the area between the placement surface and the opposing surface from a direction approximately perpendicular to the normal to the placement surface, it can measure the characteristics of the liquid sample based on the movement of the liquid sample in the entire area between the placement surface and the opposing surface, unlike devices that estimate the movement of the liquid sample by irradiating it with, for example, laser light, etc. This allows this device to measure the characteristics of the sample with high accuracy and / or under a variety of measurement conditions.

[0009] Another aspect of the present disclosure provides a program that causes a computer connected to or integrated with the above-mentioned device to analyze the characteristics of a liquid sample based on imaging data acquired by the imaging unit.

[0010] Another aspect of the present disclosure provides a method for measuring properties of a liquid, including: introducing a liquid sample between a placement surface for placing the liquid sample and an opposing surface opposite the placement surface to form a liquid column between the placement surface and the opposing surface; moving the placement surface and the opposing surface relatively in a direction approximately parallel to the normal to the placement surface to extend the liquid column; imaging at least a portion of the liquid column from a direction approximately perpendicular to the normal to the placement surface to obtain imaging data; and calculating dimensions of at least a portion of the liquid column based on the imaging data.

[0011] In addition, a program according to one aspect of the present invention can be installed or loaded onto a computer and / or device through various recording media such as optical disks such as CD-ROMs, magnetic disks, and semiconductor memories, or by downloading it via a communication network, etc.

[0012] In this specification, the term "unit" does not simply mean a physical component, but also includes cases where the functions of that component are realized by software. Furthermore, the functions of one component may be realized by two or more physical components, or the functions of two or more components may be realized by one physical component. [Effects of the Invention]

[0013] According to the present invention, it is possible to provide an apparatus, a program, and a measurement method that can measure the characteristics of a sample with high accuracy and / or under various measurement conditions. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a schematic diagram showing the configuration of a measurement device according to an embodiment of the present invention. [Figure 2] FIG. 2 is a functional block diagram of an example of an analysis unit of the measurement device according to the present embodiment. [Figure 3] FIG. 2 is a schematic diagram showing an example of the physical configuration of a computer connected to the measurement device according to the present embodiment. [Figure 4] 1 is a flowchart illustrating an example of a measurement method according to the present embodiment. [Figure 5] 3A and 3B are conceptual diagrams of imaging data acquired in the measurement method according to the present embodiment. [Figure 6] 10 is a diagram illustrating an example of measurement data processing in the measurement method according to the present embodiment. [Figure 7] The measurement results using oil are shown. [Figure 8] The measurement results using liquid soap are shown below. DETAILED DESCRIPTION OF THE INVENTION

[0015] Hereinafter, an embodiment of the present invention (hereinafter referred to as "the present embodiment") will be described in detail with reference to the drawings. However, the present invention is not limited to this embodiment, and various modifications are possible without departing from the spirit of the present invention. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. The drawings are schematic and do not necessarily correspond to actual dimensions, proportions, etc. Parts in which the dimensional relationships and proportions differ from one another may be included.

[0016] [Device configuration] 1 shows a schematic diagram of a measuring device 100 according to this embodiment. The measuring device 100 includes a placement surface 110a on which a liquid sample S is placed, an opposing surface 120a that faces the placement surface 110a and is movable relative to the placement surface 110a in a direction substantially parallel to a normal line n to the placement surface 110a, and an imaging unit 130 that images an area sandwiched between the placement surface 110a and the opposing surface 120a from a direction substantially perpendicular to the normal line n to the placement surface. The measuring device 100 shown in FIG. 1 will be described below, but the measuring device according to this embodiment only needs to have the above-described components, and the configuration described below is not essential.

[0017] In the measuring device 100, the liquid sample S is placed between the sample placement section 110 having the placement surface 110a and the facing section 120 having the facing surface 120a, and a liquid column is formed between the placement surface 110a and the facing surface 120a. Note that, although the sample placement section 110 and the facing section 120 are shown as independent configurations in the embodiment shown in Fig. 1, the sample placement section 110 and the facing section 120 may be integrated as long as the placement surface 110a faces the placement surface 110a and the two are relatively movable in a direction substantially parallel to the normal n of the placement surface 110a.

[0018] The placement surface 110a and the facing surface 120a may be, for example, circular, and the sample placement section 110 and the facing section 120 may be placed so that the line segment connecting the center (center of gravity) of the placement surface 110a and the center (center of gravity) of the facing surface 120a is approximately parallel to the normal line n. The placement surface 110a and the facing surface 120a may have a circle-equivalent diameter in the range of, for example, 0.1 to 50 mm.

[0019] A measurement unit 140 that measures the force applied from the liquid sample S placed on the placement surface 110a to at least one of the placement surface 110a and the opposing surface 120a is attached to the sample placement unit 110. In the embodiment shown in FIG. 1 , the measurement unit 140 measures the force applied from the liquid sample S to the placement surface 110a. For example, it may be an electronic balance attached to the sample placement unit 110. The measurement unit 140 may be attached to the opposing unit 120 side and measure the force applied from the liquid sample S to the opposing surface 120a. The measurement unit 140 may be attached to both the sample placement unit 110 and the opposing unit 120.

[0020] The measuring device 100 includes a driving mechanism 150 above the facing unit 120 for moving the facing surface 120a in a direction substantially parallel to the normal line n. For example, the driving mechanism 150 may be a mechanism such as a motor that electrically changes the position of the facing unit 120 and moves the facing surface 120a in a direction substantially parallel to the normal line n. The driving mechanism 150 may be attached to the sample placement unit 110 and move the placement surface 110a in a direction substantially parallel to the normal line n. The driving mechanism 150 moves at least one of the sample placement unit 110 and the facing unit 120 in a direction substantially parallel to the normal line n of the placement surface 110a, thereby moving the placement surface 110a relative to the placement surface 110a in a direction substantially parallel to the normal line n.

[0021] The measuring device 100 has a light source 160 on the opposite side of the image capturing section 130 across the sample placement section 110. When the light source 160 is installed, the image capturing section 130 can capture an image of the movement of the liquid sample S with higher accuracy.

[0022] In the measurement device 100, the sample placement unit 110, the facing unit 120, the imaging unit 130, the measurement unit 140, part of the drive mechanism 150, and the light source 160 are housed inside a housing 170. By providing the measurement device 100 with the housing 170, it is possible to reduce the influence of the measurement environment on the liquid sample S. The housing 170 may be a housing made of a material such as metal, resin, or ceramic such as glass.

[0023] In the measurement device 100, the imaging unit 130, the measurement unit 140, and the drive mechanism 150 are connected to a computer 180, and information acquired by the imaging unit 130 and the measurement unit 140 is transferred to the computer 180. The drive mechanism 150 is controlled by the computer 180 and moves the placement surface 110a and the opposing surface 120a relatively in a direction substantially parallel to the normal line n in a specified manner. The computer 180 may be integrated into at least one of the imaging unit 130, the measurement unit 140, and the drive mechanism 150. Furthermore, the computer 180 may be connected to each of the imaging unit 130, the measurement unit 140, and the drive mechanism 150 wirelessly or via a wire.

[0024] The measurement device 100 measures the properties of the liquid sample S placed on the placement surface 110a, such as the extensional rheological properties. The extensional rheological properties may be, for example, at least one selected from the group consisting of extensional behavior, extensional stress, extensional strain rate, extensional strain, and extensional viscosity.

[0025] The computer 180 functions as an analysis unit that analyzes the extension behavior of the liquid column formed between the placement surface 110a and the opposing surface 120a based on the imaging data acquired by the imaging unit 130. The computer 180 functions as the analysis unit when an analysis program stored in the computer 180 is activated.

[0026] 2 is a functional block diagram of the analysis unit, which includes an acquisition unit, a dimension calculation unit, and a characteristic analysis unit.

[0027] The acquisition unit acquires at least the imaging data acquired by the imaging unit 130. The acquisition unit may further acquire measurement data acquired by the measurement unit 140. The acquisition unit may be realized by the communication unit 180d described below. The acquisition unit may acquire all of the imaging data acquired by the imaging unit 130, or may acquire only a specified portion of the data. Similarly, the acquisition unit may acquire all of the measurement data acquired by the measurement unit 140, or may acquire only a specified portion of the data.

[0028] The dimension calculation unit calculates the dimension of at least a portion of the liquid column formed between the placement surface 110a and the opposing surface 120a based on the imaging data acquired by the acquisition unit. The dimension calculation unit may be implemented by a program stored in the RAM 180b or ROM 180c (described later) and executed by the CPU 180a. The imaging data includes multiple images, such as a video. If the imaging data is video data including multiple frames, the calculation of dimensions is performed for at least a portion of the multiple frames. Specific processing will be described later.

[0029] The characteristic analysis unit analyzes the characteristics of the liquid sample based on the dimensions of at least a portion of the liquid column calculated by the dimension calculation unit. The characteristic analysis unit may be realized by a program stored in RAM 180b or ROM 180c (described below) and executed by CPU 180a. The characteristic analysis unit may analyze the characteristics of the liquid sample by taking into account information on the measurement data acquired by the acquisition unit in addition to the dimensions of at least a portion of the liquid column calculated by the dimension calculation unit. Specific processing will be described below.

[0030] FIG. 3 is a diagram showing an example of the physical configuration of computer 180. Computer 180 has a CPU (Central Processing Unit) 180a corresponding to a processor, a RAM (Random Access Memory) 180b and a ROM (Read Only Memory) 180c corresponding to storage units, a communication unit 180d, an input unit 180e, and a display unit 180f. These components are connected via a bus so that they can send and receive data to and from each other. In this example, the functions of computer 180 are described as being configured by a single computer, but the functions of computer 180 may also be realized by combining multiple computers. The configuration shown in FIG. 3 is an example, and computer 180 may have other components or may not have some of these components.

[0031] The CPU 180a is a control unit that controls the execution of programs stored in the RAM 180b or the ROM 180c and performs data calculations and processing. The CPU 180a is a calculation unit that executes a program that analyzes the characteristics of a liquid sample based on the imaging data acquired by the imaging unit 130. Specifically, the program may include a program (dimension calculation program) that calculates the dimensions of at least a portion of the liquid column formed between the placement surface 110a and the opposing surface 120a based on the imaging data acquired by the acquisition unit, and a program (characteristic analysis program) that analyzes the characteristics of the liquid sample based on the calculated dimensions of at least a portion of the liquid column. The CPU 180a receives various data from the input unit 180e and the communication unit 180d, displays the results of data calculations on the display unit 180f, and stores the results in the RAM 180b and the ROM 180c.

[0032] The RAM 180b is a storage unit in which data can be rewritten, and may be configured, for example, with a semiconductor memory element. The RAM 180b may store programs executed by the CPU 180a. Note that these are merely examples, and the RAM 180b may store data other than these.

[0033] The ROM 180c is a storage unit from which data can be read, and may be configured with, for example, a semiconductor memory element. The ROM 180c may store, for example, data that is not rewritten.

[0034] The communication unit 180d is an interface that connects the computer 180 to the measurement device 100. The communication unit 180d may be connected to a network via a wired or wireless connection.

[0035] The input unit 180e receives data input from the user, and may include, for example, a keyboard and a touch panel.

[0036] Display unit 180f visually displays the results of calculations performed by CPU 180a, and may be configured with, for example, an LCD (Liquid Crystal Display). Display unit 180f may display the characteristics of the analyzed liquid sample.

[0037] The program according to this embodiment may be provided by being stored in a computer-readable storage medium such as RAM 180b or ROM 180c, or may be provided via a communication network connected by communication unit 180d. In computer 180, CPU 180a executes the program according to this embodiment, thereby realizing the functions of the analysis unit described with reference to FIG. 2. Note that these physical configurations are merely examples and do not necessarily have to be independent configurations. For example, computer 180 may include an LSI (Large-Scale Integration) in which CPU 180a and RAM 180b and / or ROM 180c are integrated.

[0038] [Analysis method] (overview) A method for measuring the properties of a liquid using the measurement device according to this embodiment will be described below. The measurement method according to this embodiment, when explained using the measurement device 100 shown in Fig. 1, includes introducing a liquid sample S between a placement surface 110a for placing the liquid sample and an opposing surface 120a opposing the placement surface 110a to form a liquid column between the placement surface 110a and the opposing surface 120a, relatively moving the placement surface 110a and the opposing surface 120a in a direction substantially parallel to a normal n to the placement surface 110a to extend the liquid column, imaging at least a portion of the liquid column from a direction substantially perpendicular to the normal n to the placement surface 110a to obtain imaging data, and calculating dimensions of at least a portion of the liquid column based on the imaging data.

[0039] The measurement method according to this embodiment differs from conventional measurement methods such as those described in Patent Document 1 in that it analyzes the properties of a liquid sample based on imaging data. Analyzing the properties of a liquid sample based on imaging data allows for analysis that takes into account the extensional behavior of the entire liquid column formed by the liquid sample, making it possible to accurately measure, for example, the minimum width of the extending liquid column. This allows for more accurate analysis of the properties of a liquid sample than conventional measurement methods that irradiate a laser beam and measure only the dimensions of a portion of the liquid column (for example, the width of the liquid column at a predetermined height).

[0040] The measurement method according to this embodiment may further include measuring the force applied by the liquid sample S placed on the placement surface 110a to at least one of the placement surface 110a and the opposing surface 120a, and calculating at least one of the extensional behavior, extensional stress, extensional strain rate, extensional strain, and extensional viscosity of the liquid sample based on at least one of the calculated dimensions of at least a portion of the liquid column and the measured force. In this way, analysis taking the force acting on the liquid sample into account can analyze the properties of the liquid sample with higher accuracy. In particular, in analyses using samples and / or measurement conditions that are significantly affected by surface tension or the liquid sample's own weight, the accuracy tends to be significantly improved compared to conventional measurement methods that analyze the properties of liquid samples by measuring only the dimensions of a portion of the liquid column. The measurement method according to this embodiment can quantitatively measure the physical properties of fluids exhibiting any viscosity behavior, including not only Newtonian fluids but also non-Newtonian fluids, viscoelastic fluids, and plastic fluids.

[0041] 4 is a flowchart showing an example of the measurement method according to this embodiment. In the measurement method according to this embodiment, first, a liquid sample S is introduced between a placement surface 110a for placing the liquid sample and an opposing surface 120a opposite to the placement surface 110a, thereby forming a liquid column between the placement surface 110a and the opposing surface 120a (hereinafter also referred to as "sample introduction step S1" or "step S1"). Here, the sample to be introduced is not particularly limited, and may be transparent or may have a color.

[0042] The sample introduction step S1 may be, for example, a step of separating the placement surface 110a and the opposing surface 120a by an appropriate distance and introducing the liquid sample S into the space between the placement surface 110a and the opposing surface 120a to form a liquid column. Alternatively, the sample introduction step S1 may be a step of separating the placement surface 110a and the opposing surface 120a sufficiently, introducing the liquid sample S into the placement surface 110a, and then bringing the opposing surface 120a close to the placement surface 110a to form a liquid column of the liquid sample S in the space between the placement surface 110a and the opposing surface 120a.

[0043] In the sample introduction step S1, it is preferable to adjust the amount of liquid sample S introduced and the distance between the placement surface 110a and the opposing surface 120a so that, when observed from a direction approximately perpendicular to the normal n of the placement surface 110a, the width of the placement surface 110a and the opposing surface 120a and the thickness (width) of the liquid column formed by the liquid sample S are approximately equal (see Figure 5(a) described below).

[0044] Next, at least a portion of the liquid column is imaged from a direction substantially perpendicular to the normal n of the placement surface 110a to acquire image data (hereinafter also referred to as "data acquisition step S2" or "step S2"). Here, the image data is acquired by the imaging unit 130.

[0045] In the data acquisition step S2, imaging data is acquired while the liquid column is being extended by relatively moving the placement surface 110a and the opposing surface 120a in a direction substantially parallel to the normal n of the placement surface 110a. This allows the extension behavior of the liquid sample S, i.e., the change in shape when the liquid column formed by the liquid sample S is extended, to be acquired as imaging data.

[0046] The imaging data preferably includes, for example, within the imaging range, at least the placement surface 110a, the opposing surface 120a, and the liquid sample S. This makes it possible to acquire the overall extension behavior of the liquid column formed by the liquid sample S.

[0047] In the data acquisition step S2, in addition to the imaging data, it is preferable to measure the force applied from the liquid sample S placed on the placement surface 110a to at least one of the placement surface 110a and the opposing surface 120a to acquire measurement data. When acquiring measurement data in this manner, the characteristics of the liquid sample can be analyzed taking into account information from the measurement data in addition to the imaging data. Here, the measurement data is acquired by the measurement unit 140.

[0048] In particular, when a highly viscous liquid sample or a non-Newtonian liquid containing particles or polymers is used as the liquid sample S, it is preferable to acquire measurement data in step S2. By acquiring the measurement data and analyzing the characteristics of the liquid sample while taking into account the information from the measurement data, it is possible to perform an analysis that takes into account shear stress, extensional stress, and the like resulting from interactions between molecules in the sample. Therefore, when acquiring the measurement data, it is preferable to acquire the measurement data so that the timing at which each frame of the imaging data is acquired corresponds to the timing at which each piece of data in the measurement data is obtained. Therefore, it is preferable that the measurement data include real-time measurement data obtained when the placement surface 110a and the opposing surface 120a are moved relatively in a direction approximately parallel to the normal n of the placement surface 110a to extend the liquid column.

[0049] The measurement data may include information on the force acting from the liquid sample S on at least one of the placement surface 110a and the opposing surface 120a. The measurement data includes information on the force W0 acting on the placement surface 110a when the liquid sample S is placed on the placement surface 110a, and information on the force W0 acting on the placement surface 110a when the liquid sample S placed on the placement surface 110a forms a liquid column. S and information regarding

[0050] The force W0 corresponds to the force applied to the placement surface 110a after the liquid sample S is placed on the placement surface 110a and before the liquid sample S comes into contact with the opposing surface 120a. S corresponds to the force acting on the placement surface 110a when the width D when the liquid sample S is observed from the imaging direction is made approximately equal to the width of the placement surface 110a and the opposing surface 120a, as shown in Figure 5(a) described below.

[0051] Thus, the force W0 and the force W S By acquiring information on the above, it is possible to carry out an analysis that takes into account the influence of the surface tension of the liquid sample S with high precision, as will be described later.

[0052] The measurement data further includes the force W acting on the placement surface 110a after the liquid column is cut off by the placement surface 110a and the opposing surface 120a moving away from each other. F It may contain information about the force W F By acquiring information on the above, it is possible to carry out an analysis that takes into account the influence of the surface tension of the liquid sample S with high precision, as will be described later.

[0053] The measurement data preferably includes real-time measurement data obtained when the liquid column is extended by relatively moving the placement surface 110a and the opposing surface 120a in a direction substantially parallel to the normal n of the placement surface 110a.

[0054] 5 is a conceptual diagram of the imaging data acquired in the data acquisition step S2. As shown in FIG. 5, the imaging data may include a frame (FIG. 5(a)) in which the width D of the liquid sample S when observed from the imaging direction is approximately equal to the widths of the placement surface 110a and the opposing surface 120a, a frame (FIG. 5(b)) in which the placement surface 110a and the opposing surface 120a are relatively separated from each other, thereby extending the liquid column formed by the liquid sample S, and a frame (FIG. 5(c)) in which the placement surface 110a and the opposing surface 120a are further separated from each other, thereby cutting the liquid column formed by the liquid sample S. Here, in the frame shown in FIG. 5(c), the width D of the liquid column is approximately zero. The imaging data may include multiple frames in which the liquid column corresponding to FIG. 5(b) is extending.

[0055] 4, an overview of the measurement method according to this embodiment will be described. Following step S2, the dimensions of at least a portion of the liquid column are calculated based on the imaging data (hereinafter also referred to as "dimension calculation step S3" or "step S3").

[0056] The dimension calculation step S3 may be performed after all the imaging data has been acquired in step S2, or the dimension calculation step S3 may be performed sequentially for each frame of the acquired imaging data while the imaging data is being acquired in step S2.

[0057] In the dimension calculation step S3, the imaging data is analyzed to calculate the dimension of at least a portion of the liquid column formed between the placement surface 110a and the opposing surface 120a for at least one frame included in the imaging data, preferably for all frames from the frame corresponding to FIG. 5(a) to the frame corresponding to FIG. 5(c). The calculated dimension is preferably the minimum width or minimum radius of the liquid column. Explained using FIG. 5, the calculated dimension is preferably the minimum width D of the liquid column or the minimum radius, which is D / 2.

[0058] The minimum width or minimum radius of the liquid column can be determined, for example, by measuring the minimum radial width of the liquid column in a specified region including the center of the liquid column in the height direction for at least one frame included in the imaging data, and calculating the minimum width as the minimum width of the liquid column in that frame.

[0059] More specifically, to calculate the minimum width or minimum radius of the liquid column, for example, for the frame for which the minimum width or minimum radius of the liquid column is to be calculated, the width of the liquid column is measured in a predetermined region including the center of the liquid column in the height direction, and the narrowest part in the predetermined region is determined to be the minimum width of the liquid column. The width of the liquid column can be measured, for example, by measuring the width in the in-plane direction of the placement surface 110a and the opposing surface 120a (the horizontal direction in Figure 5, which is the direction perpendicular to the normal n of the placement surface 110a).

[0060] The predetermined region for measuring the minimum radial width of the liquid column preferably includes the entire region sandwiched between the mounting surface 110a and the opposing surface 120a. When the liquid column is extended, the minimum width of the liquid column ideally is the width passing through the center of the liquid column in the height direction. However, depending on the weight of the liquid sample S and the extension characteristics, the minimum width of the liquid column may deviate from the center of the liquid column in the height direction. Therefore, by measuring the width of the liquid column over the entire region sandwiched between the mounting surface 110a and the opposing surface 120a and calculating the minimum width of the liquid column, the minimum width of the liquid column can be calculated with greater accuracy.

[0061] To calculate the minimum width of the liquid column in the entire region sandwiched between the placement surface 110a and the opposing surface 120a, for example, position information of the sample placement unit 110 and the opposing unit 120 may be acquired, the positions of the placement surface 110a and the opposing surface 120a may be estimated, and the region between the estimated positions of the placement surface 110a and the opposing surface 120a may be estimated as the region sandwiched between the placement surface 110a and the opposing surface 120a. Methods for acquiring the position information of the sample placement unit 110 and the opposing unit 120 include, for example, acquiring control information of the drive mechanism 150 to acquire the positions of the sample placement unit 110 and the opposing unit 120 corresponding to timing (e.g., time) corresponding to each frame, or attaching marks indicating specific positions to the sample placement unit 110 and the opposing unit 120 and reading the marks in each frame to acquire the positions of the sample placement unit 110 and the opposing unit 120.

[0062] When a transparent liquid is used as the liquid sample S, in order to accurately obtain the dimensions of the liquid column in step S3, it is preferable to appropriately adjust the imaging conditions by the imaging unit 130, the irradiation conditions of the light source 160, and the conditions of the obtained imaging data (e.g., brightness and contrast) to make it easier to read the end of the liquid column.

[0063] Following step S3, the characteristics of the liquid sample S are analyzed based on the dimensions of the liquid column calculated in step S3 (hereinafter also referred to as "analysis step S4" or "step S4").

[0064] The analysis in analysis step S4, which is based solely on the dimensions of the liquid column calculated in step S3, i.e., the imaging data, can include an analysis of the elongation behavior and / or elongational strain of the liquid sample S. That is, by analyzing the dimensional changes of the liquid column as it elongates, it is possible to analyze the type of elongation behavior the liquid sample will exhibit when it is elongated. By analyzing such elongation behavior, it is possible to analyze the occurrence and causes of defects in industrially important processes, such as thickness unevenness in die coating or curtain coating, stringing in screen printing, mist in printing or roll coating, stringing in dipping, and thread breakage in spinning.

[0065] In addition, it is also possible to analyze other parameters such as elongational stress, elongational strain rate, and elongational viscosity. In this case, the surface tension value of the liquid sample S is input as a representative value, and the analysis is performed assuming that the elongational stress is caused by the surface tension.

[0066] In the measurement method according to this embodiment, the properties of the liquid sample are analyzed taking into account not only the imaging data but also the measurement data, thereby enabling the extensional stress, extensional strain rate, extensional viscosity, etc. to be analyzed with higher accuracy.

[0067] Therefore, a method for analyzing the properties of a liquid sample using both imaging data and measurement data will be described below. The following analysis method may include, for example, calculating the minimum radius and extensional strain of the liquid column formed between the placement surface 110a and the opposing surface 120a based on the imaging data, and calculating the extensional viscosity of the liquid column based on the measurement data and the calculated minimum radius and extensional strain of the liquid column.

[0068] (Analysis using imaging and measurement data) In the CaBER flow field model, when a liquid column (capillary) elongates, assuming that the minimum radius of the liquid column at the center (capillary radius) changes from R0 to R(t) over time, the extensional strain (Hencky strain) ε is expressed by the following equation (1): ε = -2ln{R(t) / R0} (1)

[0069] The elongation strain rate at this time is expressed by equation (2). dε / dt = -{2 / R(t)}{dR(t) / dt} (2)

[0070] In this case, if the change in force due to elongational flow resistance over time is N(t), the elongational stress (stress due to elongational flow) σ(t) is expressed by equation (3). σ(t) = N(t) / πR(t) 2 (3)

[0071] Here, the extensional viscosity η ex is defined as the extensional stress divided by the extensional strain rate in equation (4). η ex = σ(t) / (dε / dt) (4)

[0072] Here, if the total force related to this flow is F(t), F(t) is expressed as the sum of the force N(t) due to the extensional flow resistance, the surface tension of the sample liquid, and the weight of the sample liquid related to the extensional flow, as shown in equation (5). F(t) = N(t)+πR(t)Γ+ρgV (5) where Γ is the surface tension of the sample liquid, ρ is the sample density, and V is the volume of the sample that affects the time change of R(t).

[0073] Therefore, from the above formula, the extensional viscosity η ex is calculated by equation (6). η ex = {F(t)-πR(t)Γ-ρgV} / {(dε / dt)πR(t) 2} (6)

[0074] In the above, the effect of inertia is ignored because it is extremely small when considering the amount of sample and acceleration in normal viscosity measurements. When measurement data is not used, the extensional viscosity can be calculated by ignoring the term for the weight of the sample liquid (ρgV) in equation (6) above and setting the surface tension as a representative value. In other words, under conditions where the force generated on the placement surface or the opposing surface is small and the reliability of measurement accuracy is low, the extensional viscosity can be calculated using surface tension.

[0075] The case where measurement data is used will be described below. When the liquid sample S is placed on the placement surface 110a and measurement is performed, the following measurement data can be obtained. Here, F is a value measured by the measurement unit 140. 1) Increase the distance between the placement surface and the opposing surface and reset the value of the measurement unit: F=0 2) Place the liquid sample on the placement surface and measure the total weight (units are converted to N): F=W0 3) When the placement surface and the opposing surface are brought close to each other and come into contact with the liquid sample, the liquid column remains stationary while maintaining its shape: F=W S (The force generated by surface tension is W0-W S becomes) 4) Again, reset the value of the measuring section to zero and raise the counter surface at a constant speed: F=F(t). 5) After the liquid column is cut, measure the weight of the liquid sample remaining on the surface: F = W F (The weight attached to the opposing surface is W0-(W F +W S ) is)

[0076] The weight of the liquid involved in the elongational flow at the thinnest part of the liquid column is the weight of the sample remaining in the placement section (W F +W S ) and the weight of the sample attached to the opposing surface, and can be expressed by the following equation (7). (W F +W S )-{W0-(W F +W S )} = 2(W F +W S )-W0(7)

[0077] Also, the force due to surface tension is initially W0-W S In this case, the radius of the liquid column is the radius of the placement surface R d Therefore, the surface tension Γ can be calculated from these as in equation (8). However, in viscosity calculations using measured data, (W0-W S ) is often assumed to be much smaller than F(t), and therefore the effect of surface tension can be assumed to be negligible. Γ = (W0-W S ) / 2πR d (8)

[0078] Therefore, by substituting equation (7) into equation (6), we obtain equation (9) which takes into account the weight of the sample liquid involved in the extensional flow. η ex = {F(t)-{2(W F +W S )-W0}} / {(dε / dt)πR(t) 2} (9)

[0079] If the effect of surface tension is not ignored, equations (7) and (8) can be substituted into equation (6) to obtain equation (9'), which takes into account the surface tension and the weight of the sample liquid involved in elongational flow. η ex = {F(t)-(W0-W S )(R(t) / R d )-{2(W F +W S )-W0}} / {(dε / dt)πR(t) 2} (9')

[0080] In the above, it is assumed that if a liquid column of the same diameter is initially formed between the placement surface and the opposing surface, the subsequent elongational flow behavior will be the same. However, equation (9) includes a term for the weight of the liquid sample remaining on the placement surface, which can be inconvenient in the measurement program, as the value of equation (9) is determined after measurement. Also, under normal measurement conditions, the value of the weight of the sample liquid involved in elongational flow is very small compared to the other terms. Therefore, the term for the weight of the sample liquid involved in elongational flow {2(W F+W S )-W0} from equation (9), we obtain equation (10). η ex = F(t) / {(dε / dt)πR(t) 2} (10)

[0081] For high-viscosity liquids, F(t) measured in step 4) above is the flow resistance caused by extensional flow, and viscosity is calculated directly from this. On the other hand, surface tension is involved in low-viscosity liquids. However, for low-viscosity and high-viscosity liquids, the weight of the sample not involved in the flow is included in the measured F(t) just before the liquid column breaks, and this effect must be taken into account. Because the effect of this weight becomes significant in the latter stages of extensional flow in this measurement, in the following, we will use the measured F(t) as is until the tensile force at the opposing part peaks (negative peak) during the first half of the liquid column formation process. In other words, until the tensile force peaks, we will calculate the extensional viscosity using Equation (10).

[0082] With reference to Figure 6, the correction for the weight of the sample not involved in the flow after the tensile force has peaked is explained below. As shown as F(t) in Figure 6, the value measured by the measurement unit 140 is 0 when the liquid column begins to extend, then takes a negative value, peaks, passes through 0, and becomes a constant positive value, as if a compressive force were acting. Here, the value at the peak is designated A, and the constant value after the liquid column breaks is designated B.

[0083] Since the extensional stress can be considered to be 0 in the final stage of the measurement, we assumed that the constant value B after the liquid column was cut was the effect of the weight of the sample that was not involved in the flow, and corrected for the effect of this weight. Specifically, the curve obtained by shifting the measured value F(t) after the peak downward by B (the curve represented by F(t)-B in Figure 6) was multiplied by a constant (A / (AB)) so that the values ​​at the peak of the tensile force matched (the curve represented by {A / (AB)}{F(t)-B} in Figure 6).

[0084] The curve represented by {A / (AB)}{F(t)-B} in Figure 6 is a model that takes into account the effect of the sample's own weight. Therefore, by substituting this into F(t) in equation (10), the extensional viscosity, taking into account the weight of the sample not involved in the flow, can be calculated as equation (11). η ex ≒ {A / (AB)}{F(t)-B} / (dε / dt)πR(t) 2 (11)

[0085] In this way, the extensional viscosity can be calculated using equation (10) until the measurement value in measurement unit 140 reaches the peak of the tensile force (negative), and after the peak, using equation (11). Note that because measurement unit 140 is configured to be provided in sample placement unit 110, the measurement value of measurement unit 140 is negative, and the extensional viscosity value is also calculated to be negative; however, if the configuration of measurement unit 140 is changed, the above equation can be changed as appropriate.

[0086] [Example] The oil and liquid soap samples were analyzed using the measurement device and analysis method of the present embodiment. The analysis below uses both the image data and the measurement data.

[0087] First, commercially available oil was placed on the mounting surface, and then the opposing surface was brought close to form a liquid column of oil. The gap between the mounting surface and the opposing surface at this time was set to the initial gap value shown below. The sample that protruded from the mounting surface and the opposing surface was removed, and while measuring the force applied from the sample to the mounting surface, once this force stabilized, the opposing surface was moved away from the mounting surface at the following pulling speed and for the following pulling distance. (Measurement conditions) Initial gap: 1mm Pulling speed: 10 mm / sec Pulling distance: 10mm

[0088] The measurement results are shown in Figure 7. Figure 7 shows the measurement results for two types of oil. A transient response of flow is observed at the beginning of the measurement, but in the region where extensional flow becomes dominant, the extensional viscosity becomes constant regardless of strain. This shows that the two types of oil can be treated as Newtonian fluids.

[0089] Next, commercially available liquid soap was placed on the placement surface, and the opposing surface was brought closer to form a liquid column of liquid soap. The gap between the placement surface and the opposing surface at this time was taken as the initial gap value below. The sample that protruded from the placement surface and the opposing surface was removed, and while measuring the force applied from the sample to the placement surface, once this force stabilized, the opposing surface was moved in a direction away from the placement surface so as to achieve the following pulling distance at the following pulling speed. (Measurement conditions) Initial gap: 1mm Pulling speed: 10 mm / sec Pull distance: 5mm

[0090] The measurement results are shown in Figure 8. A transient response of flow was observed at the beginning of the measurement, but in the region where elongational flow became dominant, the extensional viscosity tended to increase due to changes in the internal structure of the liquid caused by extensional strain. In this way, the measurement device and analysis method of this embodiment were able to measure the extensional viscosity of a non-Newtonian fluid.

[0091] The above-described embodiments are intended to facilitate understanding of the present invention and are not intended to limit the present invention. The elements of the embodiments, as well as their arrangement, materials, conditions, shapes, sizes, etc., are not limited to those illustrated and can be modified as appropriate. Furthermore, configurations shown in different embodiments can be partially substituted or combined with each other.

[0092] [Note] The present invention includes the following embodiments. [1] a placement surface for placing a liquid sample thereon, and an opposing surface facing the placement surface and movable relative to the placement surface in a direction substantially parallel to a normal to the placement surface; an imaging unit that images an area sandwiched between the placement surface and the opposing surface from a direction substantially perpendicular to a normal to the placement surface; Equipped with A device for measuring the properties of liquids. [2] a measuring unit that measures a force applied from the liquid sample placed on the placement surface to at least one of the placement surface and the opposing surface, [1] The device described in [1]. [3] an analysis unit configured to analyze the extension behavior of a liquid column formed between the placement surface and the opposing surface based on the imaging data acquired by the imaging unit; [1] or [2]. [4] A computer connected to or integrated with the device according to any one of [1] to [3], A program that executes analyzing the characteristics of the liquid sample based on the imaging data acquired by the imaging unit. [5] The computer, and analyzing the imaging data to calculate a dimension of at least a part of a liquid column formed between the placement surface and the opposing surface. [4] The program described in [6] the calculated dimension is the minimum width or minimum radius of the liquid column; [5] The program described in. [7] calculating a minimum width or a minimum radius of the liquid column, measuring a minimum radial width of the liquid column in a predetermined region including a center portion of the liquid column in the height direction for at least one frame included in the imaging data, and calculating the minimum width as the minimum width of the liquid column in the frame; [6] The program described in. [8] the predetermined area includes the entire area sandwiched between the placement surface and the opposing surface, [7] The program described in. [9] [2] A computer connected to or integrated with the device described in [2] and analyzing the characteristics of the liquid sample based on the measurement data acquired by the measurement unit and the imaging data acquired by the imaging unit. A program according to any one of [4] to [8].

[10] The computer, calculating a minimum radius and an extensional strain of a liquid column formed between the placement surface and the opposing surface based on the imaging data; calculating an extensional viscosity of the liquid column based on the measurement data and the calculated minimum radius and extensional strain of the liquid column; Then, [9] The program described in.

[11] The measurement data is Information about a force W0 acting on the placement surface when the liquid sample is placed on the placement surface; and The force W acting on the placement surface when the liquid sample placed on the placement surface forms the liquid column S Information about Including,

[10] The program described in.

[12] The measurement data is a force W acting on the placement surface after the liquid column is cut by the placement surface and the opposing surface being relatively separated from each other. F Further information about

[11] The program described in.

[13] for measuring at least one selected from the elongation behavior, elongation stress, elongation strain rate, elongation strain, and elongation viscosity of the liquid sample; A program according to any one of [4] to

[10] .

[14] introducing a liquid sample between a placement surface for placing a liquid sample and an opposing surface facing the placement surface to form a liquid column between the placement surface and the opposing surface; extending the liquid column by relatively moving the arrangement surface and the opposing surface in a direction substantially parallel to a normal to the arrangement surface; capturing an image of at least a portion of the liquid column from a direction substantially perpendicular to a normal to the placement surface, and acquiring image data; calculating a dimension of at least a portion of the liquid column based on the imaging data; A method for measuring a property of a liquid, comprising:

[15] measuring a force applied from the liquid sample placed on the placement surface to at least one of the placement surface and the opposing surface; calculating at least one of an elongation behavior, an elongation stress, an elongation strain rate, an elongation strain, and an elongation viscosity of the liquid sample based on at least one of the calculated dimension of at least a portion of the liquid column and the measured force; further comprising:

[14] The method described in

[14] . [Explanation of symbols]

[0093] 100...measuring device, 110...sample placement section, 110a...placement surface, 120...opposing section, 120a...opposing surface, 130...imaging section, 140...measuring section, 150...driving mechanism, 160...light source, 170...casing, 180...computer.

Claims

1. a placement surface for placing a liquid sample thereon, and an opposing surface facing the placement surface and movable relative to the placement surface in a direction substantially parallel to a normal to the placement surface; an imaging unit that images an area sandwiched between the placement surface and the opposing surface from a direction substantially perpendicular to a normal to the placement surface; Equipped with A device for measuring the properties of liquids.

2. a measuring unit that measures a force applied from the liquid sample placed on the placement surface to at least one of the placement surface and the opposing surface, 10. The apparatus of claim 1.

3. an analysis unit configured to analyze the extension behavior of a liquid column formed between the placement surface and the opposing surface based on the imaging data acquired by the imaging unit; 10. The apparatus of claim 1.

4. A computer connected to or integrated with the device according to any one of claims 1 to 3, A program that executes analyzing the characteristics of the liquid sample based on the imaging data acquired by the imaging unit.

5. The computer, and analyzing the imaging data to calculate a dimension of at least a part of a liquid column formed between the placement surface and the opposing surface. The program according to claim 4.

6. the calculated dimension is the minimum width or minimum radius of the liquid column; The program according to claim 5.

7. calculating a minimum width or a minimum radius of the liquid column, measuring a minimum radial width of the liquid column in a predetermined region including a center portion of the liquid column in the height direction for at least one frame included in the imaging data, and calculating the minimum width as the minimum width of the liquid column in the frame; The program according to claim 6.

8. the predetermined area includes the entire area sandwiched between the placement surface and the opposing surface, The program according to claim 7.

9. A computer connected to or integrated with the device according to claim 2, and analyzing the characteristics of the liquid sample based on the measurement data acquired by the measurement unit and the imaging data acquired by the imaging unit. The program according to claim 4.

10. The computer, calculating a minimum radius and an extensional strain of a liquid column formed between the placement surface and the opposing surface based on the imaging data; calculating an extensional viscosity of the liquid column based on the measurement data and the calculated minimum radius and extensional strain of the liquid column; Then, The program according to claim 9.

11. The measurement data is The force W applied to the placement surface when the liquid sample is placed on the placement surface 0 Information about The force W acting on the placement surface when the liquid sample placed on the placement surface forms the liquid column S Information about Including, The program according to claim 10.

12. The measurement data is a force W acting on the placement surface after the liquid column is cut by the placement surface and the opposing surface being relatively separated from each other. F Further information about The program according to claim 11.

13. for measuring at least one selected from the elongation behavior, elongation stress, elongation strain rate, elongation strain, and elongation viscosity of the liquid sample; The program according to claim 4.

14. introducing a liquid sample between a placement surface for placing a liquid sample and an opposing surface facing the placement surface to form a liquid column between the placement surface and the opposing surface; extending the liquid column by relatively moving the arrangement surface and the opposing surface in a direction substantially parallel to a normal to the arrangement surface; capturing an image of at least a portion of the liquid column from a direction substantially perpendicular to a normal to the placement surface, and acquiring image data; calculating a dimension of at least a portion of the liquid column based on the imaging data; A method for measuring a property of a liquid, comprising:

15. measuring a force applied from the liquid sample placed on the placement surface to at least one of the placement surface and the opposing surface; calculating at least one of an elongation behavior, an elongation stress, an elongation strain rate, an elongation strain, and an elongation viscosity of the liquid sample based on at least one of the calculated dimension of at least a portion of the liquid column and the measured force; further comprising:

15. The method of claim 14.

Images