Thermal analysis device and thermal analysis method

Abstract

[Problem] To provide a thermal analysis device or the like capable of enhancing the stability of a baseline. [Solution] One aspect of the present invention provides a thermal analysis device comprising: a heating furnace having a cylindrical heating unit; a first sample holder and a second sample holder disposed in the heating unit; a detection unit configured to detect at least one of the weight of each of the first sample holder and the second sample holder and the temperature difference between the first sample holder and the second sample holder; a heat equalizing member disposed in the heating unit so as to cover at least part of each of the first sample holder and the second sample holder; and a support member supporting the heat equalizing member, wherein the support member extends from the outside of the heating unit to a holding position of the heat equalizing member.

Description

Thermal Analysis Apparatus and Thermal Analysis Method

[0001] The present invention relates to a thermal analysis apparatus and a thermal analysis method.

[0002] Patent Document 1 discloses a thermal analysis apparatus that suppresses inhibition of reactions caused by the self-generated atmosphere of a sample and reduces the influence of radiation on the sample by providing a lid that allows gas to flow through the sample container.

[0003] Japanese Patent No. 6706522

[0004] In thermal analysis apparatuses, the stability of the baseline for thermal analysis decreases due to positional deviation of the sample container in the heating furnace or positional deviation of the heating section. Even if a lid is provided on the sample container as in the conventional art, a sufficient improvement effect on the reduction in baseline stability caused by the aforementioned positional deviation of the sample container or the heating section cannot be obtained.

[0005] In view of the above circumstances, the present invention aims to provide a thermal analysis apparatus and the like that can improve the stability of the baseline.

[0006] According to one aspect of the present invention, there is provided a thermal analysis apparatus comprising: a heating furnace having a cylindrical heating section; a first sample holder and a second sample holder disposed inside the heating section; a detection unit configured to detect at least one of the respective weights of the first sample holder and the second sample holder, and the temperature difference between the first sample holder and the second sample holder; a temperature equalizing member disposed inside the heating section so as to cover at least a portion of each of the first sample holder and the second sample holder; and a support member that supports the temperature equalizing member, wherein the support member extends from outside the heating section to the holding position of the temperature equalizing member.

[0007] According to this configuration, when the first sample holder and the second sample holder are heated by the heating section, the ambient temperatures around the first sample holder and the second sample holder covered by the temperature equalizing member become close to each other. Further, since the temperature equalizing member is supported by the support member extending from outside the heating section, the temperature difference between the temperature equalizing member and the first sample holder and the second sample holder is reduced, and the generation of radiation is suppressed. As a result, the baseline of thermal analysis can be stabilized.

[0008] This is a schematic diagram of the thermal analysis apparatus 1 according to this embodiment. This is a schematic cross-sectional view of the heating furnace 2. This is a schematic diagram of the weight measuring mechanism of the detection unit 4. This is a schematic diagram of the temperature difference measuring mechanism of the detection unit 4. This is a schematic front view and rear view of the heat equalization member 7. This is a schematic side view of the heat equalization member 7 and the support member 8. This is a schematic diagram showing the positional relationship between the protective tube 21, the heat equalization member 7, the first sample holder 3A and the second sample holder 3B. This is a flow chart showing an example of a thermal analysis method.

[0009] Embodiments of the present invention will be described below with reference to the drawings. The various features shown in the embodiments below can be combined with each other.

[0010] <Thermal Analysis Apparatus 1> Figure 1 is a schematic diagram of the thermal analysis apparatus 1 according to this embodiment. The thermal analysis apparatus 1 is an apparatus that measures the thermal behavior of a sample when the sample is heated (for example, thermogravimetric analysis (TG), differential thermal analysis (DTA), simultaneous thermogravimetric and differential thermal analysis (TG-DTA), differential scanning calorimetry (DSC), etc.). The thermal analysis apparatus 1 comprises a heating furnace 2, a first sample holder 3A, a second sample holder 3B, a detection unit 4, a gas supply unit 5, and a control device 6.

[0011] <Heating Furnace 2> The heating furnace 2 is configured to simultaneously heat the sample to be analyzed for thermal analysis (the object to be measured) (hereinafter referred to as the "object to be measured sample") and a standard sample whose thermal behavior (change in state due to temperature change) is known. Figure 2 is a schematic cross-sectional view of the heating furnace 2. The heating furnace 2 has a protective tube 21, a heater 22, and a discharge passage 23.

[0012] The protective tube 21 is a cylindrical tube with an internal space for housing the sample to be measured and the standard sample. The first end 21A of the protective tube 21 (the right end in Figure 2) is supported by the housing 9 via the base 82 of the support member 8, which will be described later. The housing 9 is, for example, a structural member that houses the detection unit 4. In this embodiment, the protective tube 21 is arranged with its central axis aligned with the horizontal direction.

[0013] The second end 21B of the protective tube 21 (the left end in Figure 2) is tapered toward the tip, and a discharge passage 23 is connected to the tip. The protective tube 21 has a constant inner diameter along the axial direction, at least in the heated region covered by the heater 22.

[0014] The heater 22 is a cylindrical member configured to heat the inside of the protective tube 21. Specifically, the heater 22 is configured to heat the protective tube 21 by passing current through a heating element located outside the protective tube 21. The heating element is, for example, a metal wire such as an alloy containing nickel and chromium. In other words, the heating furnace 2 is a resistance heating furnace. With this configuration, in a thermal analysis apparatus 1 using a resistance heating furnace with a relatively simple configuration, the baseline of the thermal analysis can be stabilized by the heat equalization member 7 and support member 8, which will be described later.

[0015] Here, "baseline" refers to the baseline of the thermal behavior in a curve (mass curve, temperature curve, heat flow curve, etc.) showing the results of thermal analysis, when no thermal events (e.g., melting, crystallization, phase transition, decomposition, oxidation-reduction reaction, etc.) have occurred. From the viewpoint of the accuracy of thermal analysis, the baseline is preferably a flat straight line.

[0016] The heater 22 is positioned to cover the outer surface of the protective tube 21 from the radially outer side. Furthermore, the axial length of the heater 22 is shorter than the axial length of the protective tube 21. In other words, the heater 22 covers only a portion of the axial region of the protective tube 21.

[0017] Within the internal space of the protective tube 21, the heating region that overlaps radially with the heater 22 (i.e., the region directly heated by the heater 22) corresponds to the heating section 2A. In other words, the heating furnace 2 has a cylindrical heating section 2A, which is composed of the heater 22 and the portion of the protective tube 21 covered by the heater 22. The inner diameter of the heating section 2A is constant along the axial direction. The first sample holder 3A and the second sample holder 3B, which will be described later, are arranged inside the heating section 2A (heating region). A cylindrical insulating material that covers the heater 22 from the radial outside may be arranged on the radially outside of the heater 22.

[0018] The discharge passage 23 is configured to discharge the gas supplied into the protective pipe 21 by the gas supply unit 5, the atmosphere generated inside the protective pipe 21, etc., to the outside of the protective pipe 21. The discharge passage 23 is connected to the second end 21B of the protective pipe 21. For example, when performing gas analysis, a supply pipe configured to supply gas to a gas analyzer is connected to the end of the discharge passage 23.

[0019] <First sample holder 3A and second sample holder 3B> The first sample holder 3A is a container configured to hold the sample to be measured. The second sample holder 3B is a container configured to hold a standard sample. The first sample holder 3A and the second sample holder 3B are each located inside the heating section 2A (i.e., inside the heating area provided by the heater 22 in the protective tube 21).

[0020] The first sample holder 3A and the second sample holder 3B each include a sample container 31 for containing a sample, a heat-sensitive plate 32 for supporting the sample container 31 from below, a connector portion 33, and a connecting thermocouple 34.

[0021] The sample container 31 is made of a material with high heat resistance, insulation, and thermal resistance, such as alumina. The sample container 31 is supported by a heat-sensing plate 32. The sample is placed on the heat-sensing plate 32. The heat-sensing plate 32 is supported by a connector portion 33 and a connecting thermocouple 34. The heat-sensing plate 32 is made of a material with high thermal conductivity, such as platinum.

[0022] The connector section 33 is connected to the first balance beam 41A or the second balance beam 41B of the detection unit 4, which will be described later. The connector section 33 is made of, for example, alumina. A connecting thermocouple 34, which is electrically connected to the first thermocouple 43A or the second thermocouple 43B of the detection unit 4, which will be described later, is inserted through the connector section 33. The connecting thermocouple 34 is electrically connected to the heat-sensing plate 32 and also supports the heat-sensing plate 32.

[0023] Thus, the first sample holder 3A is held within the heating section 2A by the first balance beam 41A, and the second sample holder 3B is held within the heating section 2A by the second balance beam 41B.

[0024] The first sample holder 3A and the second sample holder 3B are positioned at the same location in the axial direction of the protective tube 21 (i.e., at the same distance from the discharge passage 23) in the initial state (before the weight of the sample changes due to heating). In addition, the first sample holder 3A and the second sample holder 3B are positioned at the same location in the vertical direction in the initial state.

[0025] The first sample holder 3A is supported only by the first balance beam 41A, and the second sample holder 3B is supported only by the second balance beam 41B. Furthermore, the first balance beam 41A and the second balance beam 41B are not connected and are members that swing independently of each other. In addition, the first sample holder 3A and the second sample holder 3B are not physically connected within the heating section 2A. With this configuration, the thermal analyzer 1 can be used to perform a stable baseline TG either on its own or in combination with either DTA or DSC.

[0026] The placement or removal of the sample to be measured and / or the standard sample into the first sample holder 3A or the second sample holder 3B is performed by sliding the protective tube 21 axially to expose the first sample holder 3A and the second sample holder 3B. Alternatively, the placement or removal of the sample may be performed by an automatic sample changer (ASC).

[0027] <Detection Unit 4> The detection unit 4 shown in Figure 1 is configured to detect at least one of the following: the weight of the first sample holder 3A and the second sample holder 3B, and the temperature difference between the first sample holder 3A and the second sample holder 3B. For example, when the thermal analyzer 1 is used for TG, the detection unit 4 detects the weight of the first sample holder 3A and the second sample holder 3B (i.e., the weight difference between the sample to be measured and the standard sample). Also, for example, when the thermal analyzer 1 is used for DTA, the detection unit 4 detects the temperature difference between the first sample holder 3A and the second sample holder 3B (i.e., the temperature difference between the sample to be measured and the standard sample). Furthermore, for example, when the thermal analyzer 1 is used for TG-DTA, the detection unit 4 detects both the weight of the first sample holder 3A and the second sample holder 3B, and the temperature difference between the first sample holder 3A and the second sample holder 3B.

[0028] The detection unit 4 includes a first balance beam 41A, a second balance beam 41B, a weight detection device 42, a first thermocouple 43A, a second thermocouple 43B, and a temperature detection device 44. With this configuration, a thermal analysis apparatus 1 capable of stabilizing the baseline of thermal analysis can be constructed using known components.

[0029] Figure 3 is a schematic diagram of the weight measurement mechanism of the detection unit 4. The first balance beam 41A supports the first sample holder 3A and constitutes a balance mechanism for detecting the weight of the first sample holder 3A. Specifically, the first sample holder 3A is attached to one end of the first balance beam 41A. The other end of the first balance beam 41A is located inside the weight detection device 42. Furthermore, the first balance beam 41A is supported by a pivot point 411 so that it can swing up and down around the pivot point 411.

[0030] Although not shown in the diagram, the second balance beam 41B has the same configuration as the first balance beam 41A. That is, the second balance beam 41B supports the second sample holder 3B and constitutes a balance mechanism for detecting the weight of the second sample holder 3B. Specifically, the second sample holder 3B is attached to one end of the second balance beam 41B. The other end of the second balance beam 41B is located inside the weight detection device 42. Furthermore, the second balance beam 41B is supported by a pivot point 411 so that it can swing up and down around the pivot point 411.

[0031] The weight detection device 42 is configured to detect the weights of the first sample holder 3A and the second sample holder 3B, respectively. The weight detection device 42 detects the weight of the first sample holder 3A from the tilt of the first balance beam 41A and detects the weight of the second sample holder 3B from the tilt of the second balance beam 41B.

[0032] Specifically, the weight detection device 42 has an optical sensor that detects the position (amount of deflection) of the ends of the first balance beam 41A and the second balance beam 41B (for example, shutters 412 attached to the ends). The optical sensor has, for example, a light source 421 and a light receiving element 422 arranged to sandwich the balance beam horizontally. The optical sensor detects the position of the ends of the balance beam based on the change in the amount of light received by the light receiving element 422 from the light source 421. The light receiving element 422 has, for example, a first element positioned above a reference position and a second element positioned below a reference position.

[0033] The weight detection device 42 converts the amount of light received by the light-receiving element 422 into the weight of the first sample holder 3A or the second sample holder 3B, for example, by the following procedure. That is, the weight detection device 42 uses the PID control circuit 423 to supply current to the drive coil 424 connected to the balance beam, causing the balance beam to oscillate, so that the output difference between the first and second elements of the light-receiving element 422 becomes zero (i.e., so that the end of the balance beam is in its initial position (horizontal state)). Subsequently, the weight detection device 42 uses the calculation circuit 425 to calculate the weight change of the first sample holder 3A or the second sample holder 3B from the current value supplied to the drive coil 424 to make the output difference between the first and second elements of the light-receiving element 422 zero. The relationship between the current value and the weight change is determined in advance.

[0034] Figure 4 is a schematic diagram of the temperature difference measurement mechanism of the detection unit 4. The first thermocouple 43A is a pair of different metal wires connected to the first sample holder 3A. The second thermocouple 43B is a pair of different metal wires connected to the second sample holder 3B. The first metal wire of the first thermocouple 43A and the first metal wire of the second thermocouple 43B are electrically connected to the DTA output circuit 441 of the temperature detection device 44, which will be described later. In addition, the second metal wire of the first thermocouple 43A and the second metal wire of the second thermocouple 43B are electrically connected and connected to the sample temperature measurement circuit 442 of the temperature detection device 44, which will be described later. Furthermore, the first metal wire of the first thermocouple 43A is also connected to the sample temperature measurement circuit 442 by itself.

[0035] The first thermocouple 43A is held by the first balance beam 41A (see Figure 1). Specifically, the first thermocouple 43A is inserted into the interior of the first balance beam 41A. The second thermocouple 43B is held by the second balance beam 41B. Specifically, the second thermocouple 43B is inserted into the interior of the second balance beam 41B.

[0036] The temperature detection device 44 is configured to detect the temperature difference between the first sample holder 3A and the second sample holder 3B, and the temperature of the first sample holder 3A (i.e., the temperature of the sample to be measured). The temperature detection device 44 has a DTA output circuit 441 and a sample temperature measurement circuit 442, to which the first thermocouple 43A and the second thermocouple 43B are connected as described above. The DTA output circuit 441 outputs the voltage difference generated by the temperature difference between the first sample holder 3A and the second sample holder 3B. The sample temperature measurement circuit 442 outputs the temperature of the first sample holder 3A (electromotive force with the first sample holder 3A as the contact point), which has been compensated by a temperature cold junction compensator.

[0037] <Gas Supply Unit 5> The gas supply unit 5 shown in Figure 1 is configured to supply a predetermined gas to the heating furnace 2. Specifically, the gas supply unit 5 includes a gas supply source, a flow rate control device, and a pump. The gas supplied from the gas supply source is, for example, a test gas, an unreacted gas, etc. The flow rate control device is configured to adjust the flow rate of the gas supplied into the protective tube 21. The pump of the gas supply unit 5 is configured to send gas from the gas supply source to the heating furnace 2.

[0038] <Control device 6> The control device 6 shown in Figure 1 is configured to control the heating temperature of the heating furnace 2, acquire the detection results of the detection unit 4, and control the gas flow rate of the gas supply unit 5, etc.

[0039] The control device 6 is an information processing device having a processor, a communication unit, a storage unit, a display unit, an input unit, etc. The control device 6 executes functions (steps) for controlling the heating furnace 2, the detection unit 4, the gas supply unit 5, etc., when the processor reads a program.

[0040] <Heat-Solidifying Member 7> As shown in Figure 2, the thermal analyzer 1 further comprises a heat-solidifying member 7 and a support member 8. The heat-solidifying member 7 is a member installed to uniformly heat the first sample holder 3A and the second sample holder 3B (i.e., the sample to be measured and the standard sample) within the heating section 2A.

[0041] The soaking member 7 is arranged in the heating part 2A (that is, the heating region heated by the heater 22 in the protective tube 21) so as to cover at least a part of each of the first sample holder 3A and the second sample holder 3B. That is, the soaking member 7 is arranged between the first sample holder 3A and the second sample holder 3B and the inner surface of the protective tube 21.

[0042] Figure 5 is a schematic front view and a schematic rear view of the soaking member 7. The front view of Figure 5A is a view of the soaking member 7 viewed from the second end 21B side (the discharge path 23 side) of the protective tube 21. The rear view of Figure 5B is a view of the soaking member 7 viewed from the first end 21A side (the housing 9 side) of the protective tube 21.

[0043] As shown in Figure 2 and Figure 5, the soaking member 7 comprises a cylindrical body 71 and a wall 72. The cylindrical body 71 and the wall 72 are made of metal plates. That is, the soaking member 7 comprises a metal plate. According to this configuration, a thermal analysis apparatus 1 capable of stabilizing the baseline of thermal analysis can be constructed using known materials. The soaking member 7 is made of, for example, a metal with high thermal conductivity such as platinum. Specifically, the soaking member 7 is made of a material that has higher thermal conductivity and lower emissivity than the material of the sample containers 31 of the first sample holder 3A and the second sample holder 3B.

[0044] The cylindrical body 71 covers the first sample holder 3A and the second sample holder 3B from the outside in the radial direction of the heating part 2A (the radial direction of the protective tube 21). According to this configuration, the reduction of the difference between the ambient temperatures of the first sample holder 3A and the second sample holder 3B is promoted. As a result, the baseline stability in the measurement results of the thermal analysis apparatus 1 is improved.

[0045] Specifically, the cylindrical body 71 is positioned inside the protective tube 21 with its axial direction aligned with the axial direction of the protective tube 21 (i.e., its axial direction is aligned horizontally). In the example shown in Figure 5, the cylindrical body 71 is a decagonal tube, but the cylindrical body 71 may be a cylinder or a rectangular tube other than a decagonal tube. Also, as shown in Figure 2, the axial length of the cylindrical body 71 is greater than the axial length of the protective tube 21 of the first sample holder 3A and the second sample holder 3B, and less than the axial length of the heater 22 (heating section 2A) (length of the heating area in the protective tube 21).

[0046] The wall 72 covers at least a portion of the first sample holder 3A and at least a portion of the second sample holder 3B in the axial direction of the heating section 2A (the axial direction of the protective tube 21). With this configuration, the occurrence of temperature differences between the ambient temperatures of the first sample holder 3A and the second sample holder 3B due to the flow of gas in the heater 22 is suppressed. As a result, the stability of the baseline in the measurement results of the thermal analyzer 1 is improved.

[0047] Specifically, the wall 72 constitutes a bottom wall that closes one end of the cylindrical body 71 (the end on the discharge passage 23 side, in other words, the downstream end in the gas flow direction FD within the protective tube 21). Therefore, the inner and outer surfaces of the wall 72 intersect with the axial direction of the protective tube 21 (i.e., the gas flow direction FD) (more specifically, perpendicular to the axial direction of the protective tube 21). Furthermore, the wall 72 is positioned downstream of the first sample holder 3A and the second sample holder 3B in the gas flow direction FD, and is positioned to overlap with the first sample holder 3A and the second sample holder 3B when viewed from the axial direction of the protective tube 21. Note that the end of the cylindrical body 71 opposite to the end on which the wall 72 is provided (the upstream end in the gas flow direction FD) does not have a wall, and that end of the cylindrical body 71 is open.

[0048] Further, as shown in FIG. 5, the wall 72 has an opening 73. According to this configuration, when gas passes through the interior of the soaking member 7, inhibition of the reaction caused by the native atmosphere of the samples accommodated in the first sample holder 3A and the second sample holder 3B is suppressed, so that the reaction of the samples can be detected accurately. For example, the gas supplied from the gas supply unit 5 into the protective tube 21 and entering the cylindrical body 71 passes through the opening 73 from the interior of the cylindrical body 71 and flows to the discharge passage 23. Further, the native atmosphere generated by decomposition of the measurement target sample in the first sample holder 3A or the standard sample in the second sample holder 3B also flows from the interior of the cylindrical body 71 through the opening 73 to the discharge passage 23.

[0049] Specifically, the opening 73 is provided in a central portion of the wall 72. The opening 73 has a horizontally extending strip shape (slit shape). The planar area (opening area) of the opening 73 is smaller than the planar area (wall area) of a portion of the wall 72 other than the opening 73. Further, the opening 73 is arranged so as to overlap a part of the first sample holder 3A and a part of the second sample holder 3B in the axial direction of the heater 22 (gas flow direction FD). That is, as shown in FIG. 5A, when viewed from the downstream side in the gas flow direction FD, a part of the first sample holder 3A and a part of the second sample holder 3B are each positioned within the opening 73. Note that a plurality of openings 73 separated from each other may be provided on the wall 72. For example, the wall 72 may have an opening 73 overlapping a part of the first sample holder 3A and an opening 73 overlapping a part of the second sample holder 3B.

[0050] Neither the cylindrical body 71 nor the wall 72 is in contact with the inner surface of the protective tube 21. That is, the soaking member 7 is arranged spaced apart from the inner surface of the heating unit 2A. According to this configuration, direct heat conduction from the heating unit 2A to the soaking member 7 is suppressed, so that the temperature difference between the soaking member 7 and the first sample holder 3A and the second sample holder 3B can be reduced. As a result, the stability of the baseline in the measurement results of the thermal analyzer 1 is improved.

[0051] Furthermore, neither the cylindrical body 71 nor the wall 72 is in contact with the first sample holder 3A and the second sample holder 3B. In other words, the heat equalization member 7 is positioned at a distance from the first sample holder 3A and the second sample holder 3B. Moreover, the heat equalization member 7 is also positioned at a distance from the detection unit 4 (first balance beam 41A, second balance beam 41B, etc.).

[0052] The cylindrical body 71 should be positioned such that, in its initial state before heating, the distance from the first sample holder 3A to the inner surface of the cylindrical body 71 is the same as the distance from the second sample holder 3B to the inner surface of the cylindrical body 71. Similarly, the wall 72 should be positioned such that, in its initial state before heating, the distance from the first sample holder 3A to the inner surface of the wall 72 is the same as the distance from the second sample holder 3B to the inner surface of the wall 72.

[0053] <Support Member 8> Figure 6 is a schematic side view of the heat uniforming member 7 and the support member 8. As shown in Figure 6, the support member 8 supports the heat uniforming member 7. The support member 8 extends from outside the heating section 2A to the holding position of the heat uniforming member 7 (inside the heating section 2A). The support member 8 has a first arm 81A, a second arm 81B, and a base 82.

[0054] The first arm 81A and the second arm 81B are rod-shaped members that extend along the axial direction of the heating section 2A (the axial direction of the protective tube 21). With this configuration, a thermal analyzer 1 can be constructed using known materials, which is capable of stabilizing the baseline of the thermal analysis in the measurement results of the thermal analyzer 1.

[0055] One end of the first arm 81A is attached to the upper part of the cylindrical body 71 of the heat equalization member 7. The other end of the first arm 81A is attached to the base 82. One end of the second arm 81B is attached to the lower part of the cylindrical body 71 of the heat equalization member 7. The other end of the second arm 81B is attached to the base 82. Both the first arm 81A and the second arm 81B are positioned so as not to interfere with the first balance beam 41A and the second balance beam 41B.

[0056] The base 82 is a member that supports the first arm 81A and the second arm 81B. The base 82 has a base portion 821 and a holding portion 822. The base portion 821 is a plate-shaped part whose bottom surface is connected to the housing 9. The holding portion 822 is a cylindrical part that protrudes from the base portion 821 on the side opposite to the housing 9. As shown in Figure 2, the first arm 81A and the second arm 81B are inserted into the holding portion 822. The first balance beam 41A and the second balance beam 41B are inserted into the internal space (hollow portion) of the base 82 and do not come into contact with the base 82.

[0057] The first arm 81A and the second arm 81B are made of a material with low thermal conductivity, such as alumina (preferably the same material as the sample containers 31 of the first sample holder 3A and the second sample holder 3B). The base 82 is made of a highly heat-resistant metal, such as stainless steel. In other words, the thermal conductivity of the support member 8 is lower than that of the heat-soothing member 7. With this configuration, the amount of heat dissipated from the support member 8 is reduced, making it possible to further reduce the temperature difference between the heat-soothing member 7 and the first sample holder 3A and the second sample holder 3B. As a result, the stability of the baseline in the measurement results of the thermal analyzer 1 is improved. In particular, the thermal conductivity of the portion of the support member 8 that is located inside the heating section 2A (the first arm 81A and the second arm 81B) is lower than that of the cylindrical body 71 and wall 72 of the heat-soothing member 7.

[0058] Figure 7 is a schematic diagram showing the positional relationship between the protective tube 21, the heat equalization member 7, and the first sample holder 3A and the second sample holder 3B. The relative position (radial position) of the protective tube 21 (heating section 2A) with respect to the holding positions of the first sample holder 3A and the second sample holder 3B changes depending on the measurement conditions, manufacturing variations of the equipment, etc., as indicated by the arrows in Figure 7. Therefore, if the heat equalization member 7 is not present, the distance from the first sample holder 3A to the inner surface of the protective tube 21 and the distance from the second sample holder 3B to the inner surface of the protective tube 21 change depending on the position of the protective tube 21. As a result, a difference occurs between the ambient temperature of the sample to be measured and the ambient temperature of the standard sample, reducing the measurement accuracy. In contrast, if the heat equalization member 7 is present, the variation in the temperature distribution around the first sample holder 3A and the second sample holder 3B, which are surrounded by the heat equalization member 7, becomes smaller than the variation in the temperature distribution inside the protective tube 21. As a result, the difference between the ambient temperature of the sample being measured and the ambient temperature of the standard sample is reduced, thus improving measurement accuracy.

[0059] 4. In the thermal analysis apparatus 1, when the first sample holder 3A and the second sample holder 3B are heated by the heating unit 2A, the ambient temperatures of the first sample holder 3A and the second sample holder 3B, which are covered by the heat equalization member 7, become close to each other. Furthermore, since the heat equalization member 7 is supported by the support member 8 extending from outside the heating unit 2A, the temperature difference between the heat equalization member 7 and the first sample holder 3A and the second sample holder 3B is reduced, and the generation of radiation is suppressed. As a result, the baseline of the thermal analysis in the measurement results of the thermal analysis apparatus 1 can be stabilized.

[0060] Although embodiments of the present invention have been described above, the present invention is not limited thereto and can be modified as appropriate without departing from the technical spirit of the invention.

[0061] 5. The above embodiment may also be a thermal analysis method. This thermal analysis method includes a step of heating a heating unit 2A, which contains a first sample holder 3A containing a sample to be measured and a second sample holder 3B containing a standard sample, while detecting at least one of the weights of the first sample holder 3A and the second sample holder 3B, and the temperature difference between the first sample holder 3A and the second sample holder 3B. In this step, a heat-soothing member 7 is placed inside the heating unit 2A, covering at least a portion of each of the first sample holder 3A and the second sample holder 3B. The heat-soothing member 7 is supported by a support member 8 that extends from outside the heating unit 2A to the holding position of the heat-soothing member 7.

[0062] Figure 8 is a flowchart showing an example of a thermal analysis method. In this thermal analysis method, first, the sample to be measured and the standard sample are placed in the first sample holder 3A and the second sample holder 3B, respectively (step S110). Next, the heat-distributing member 7 is placed so as to cover the first sample holder 3A and the second sample holder 3B (step S120). Subsequently, the first sample holder 3A and the second sample holder 3B are heated by the heating unit 2A, and the weight or temperature difference is detected by the detection unit 4 (step S130).

[0063] The heat equalization member 7 does not necessarily have to have a cylindrical body 71 and a wall 72. For example, the heat equalization member 7 may have only a cylindrical body 71 or only a wall 72. Also, the wall 72 does not necessarily have to have an opening 73, and the opening 73 may be provided in the peripheral wall of the cylindrical body 71. Furthermore, the heat equalization member 7 may be composed of a metal plate (a non-cylindrical plate material) that covers the first sample holder 3A and the second sample holder 3B from the radially outer side of the heating section 2A.

[0064] The thermal analysis apparatus 1 may be equipped with a heating furnace 2 other than a resistance heating furnace. For example, the thermal analysis apparatus 1 may be equipped with an electric furnace other than a resistance heating furnace as the heating furnace 2. Alternatively, the thermal analysis apparatus 1 may be equipped with an infrared heating furnace as the heating furnace 2.

[0065] If weight detection is not performed (if TG is not performed), the first sample holder 3A and the second sample holder 3B may be connected to each other within the heating section 2A. For example, the heat-sensitive plate 32 of the first sample holder 3A and the heat-sensitive plate 32 of the second sample holder 3B may be integrated. Also, the protective tube 21 (heating section 2A) may be arranged so that its central axis is aligned with the vertical direction.

[0066] The product may be provided in any of the following embodiments.

[0067] (1) A thermal analyzer comprising: a heating furnace having a cylindrical heating section; a first sample holder and a second sample holder disposed within the heating section; a detection section configured to detect at least one of the weights of the first sample holder and the second sample holder, and the temperature difference between the first sample holder and the second sample holder; a heat-soothing member disposed within the heating section so as to cover at least a portion of the first sample holder and the second sample holder; and a support member for supporting the heat-soothing member, wherein the support member extends from outside the heating section to the holding position of the heat-soothing member.

[0068] With this configuration, when the first and second containers are heated by the heating unit, the ambient temperatures of the first and second containers, which are covered by the heat-sensing member, become close to each other. Furthermore, because the heat-sensing member is supported by a support member extending from outside the heating unit, the temperature difference between the heat-sensing member and the first and second containers is reduced, and the generation of radiation is suppressed. As a result, the baseline of the thermal analysis can be stabilized.

[0069] (2) A thermal analysis apparatus as described in (1) above, wherein the heat equalization member is arranged at a distance from the inner surface of the heating section.

[0070] With this configuration, direct heat conduction from the heating element to the heat-synthesizing element is suppressed, thereby reducing the temperature difference between the heat-synthesizing element and the first and second containers. As a result, baseline stability is improved.

[0071] (3) A thermal analyzer according to (1) or (2) above, wherein the heat soaking member has a cylindrical body that covers the first sample holder and the second sample holder from the radially outer side of the heating section.

[0072] This configuration promotes a reduction in the difference in ambient temperature between the first and second containers. As a result, baseline stability is improved.

[0073] (4) A thermal analyzer according to any one of (1) to (3) above, wherein the heat soaking member has a wall that covers at least a part of the first sample holder and at least a part of the second sample holder in the axial direction of the heating section.

[0074] With this configuration, the occurrence of temperature differences between the first and second containers due to gas flow within the heating section is suppressed. As a result, baseline stability is improved.

[0075] (5) A thermal analyzer as described in (4) above, wherein the wall has an opening.

[0076] With this configuration, the gas passes through the heat-sensing member, which suppresses the inhibition of the reaction caused by the natural atmosphere surrounding the sample contained in the container, thus enabling accurate detection of the sample's reaction.

[0077] (6) A thermal analyzer according to any one of (1) to (5) above, wherein the first sample holder and the second sample holder are not physically connected within the heating section.

[0078] With this configuration, a stable baseline TG can be performed either by itself or in combination with either DTA or DSC.

[0079] (7) A thermal analyzer according to any one of (1) to (6) above, wherein the thermal conductivity of the support member is less than the thermal conductivity of the heat-soothing member.

[0080] With this configuration, the amount of heat dissipated from the support member is reduced, making it possible to further reduce the temperature difference between the heat-distributing member and the first and second containers. As a result, baseline stability is improved.

[0081] (8) A thermal analysis apparatus according to any one of (1) to (7) above, wherein the heating furnace is a resistance heating furnace.

[0082] With this configuration, the baseline of thermal analysis can be stabilized in a thermal analysis apparatus using a relatively simple resistance heating furnace.

[0083] (9) A thermal analyzer according to any one of (1) to (8) above, wherein the detection unit has at least one of a thermocouple and a balance beam, the heat soaking member has a metal plate, and the support member has a rod-shaped member extending along the axial direction of the heating unit.

[0084] With this configuration, it is possible to construct a thermal analysis apparatus capable of stabilizing the baseline of thermal analysis using known components or materials.

[0085] (10) A thermal analysis method comprising the step of detecting at least one of the weights of the first sample holder and the second sample holder, and the temperature difference between the first sample holder and the second sample holder, while heating a heating unit in which a first sample holder containing a sample and a second sample holder containing a standard sample are arranged, wherein a heat-sensing member is arranged in the heating unit to cover at least a portion of the first sample holder and the second sample holder, and the heat-sensing member is supported by a support member that extends from outside the heating unit to the holding position of the heat-sensing member.

[0086] With this configuration, when the first and second containers are heated by the heating unit, the ambient temperatures of the first and second containers, which are covered by the heat-sensing member, become close to each other. Furthermore, because the heat-sensing member is supported by a support member extending from outside the heating unit, the temperature difference between the heat-sensing member and the first and second containers is reduced, and the generation of radiation is suppressed. As a result, the baseline of the thermal analysis can be stabilized. Of course, this is not always the case.

[0087] Finally, while various embodiments relating to this disclosure have been described, these are presented as examples only and are not intended to limit the scope of the invention. These novel embodiments can be implemented in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims and their equivalents.

[0088] 1: Thermal analyzer, 2: Heating furnace, 2A: Heating section, 21: Protective tube, 21A: First end, 21B: Second end, 22: Heater, 23: Discharge passage, 3A: First sample holder, 3B: Second sample holder, 31: Sample container, 32: Heat sensing plate, 33: Connector section, 34: Connecting thermocouple, 4: Detection section, 41A: First balance beam, 41B: Second balance beam, 411: Pivot point, 412: Shutter, 42: Weight detection device, 421: Light source, 42 2: Light-receiving element, 423: PID control circuit, 424: Drive coil, 425: Calculation circuit, 43A: First thermocouple, 43B: Second thermocouple, 44: Temperature detection device, 441: DTA output circuit, 442: Sample temperature measurement circuit, 5: Gas supply unit, 6: Control device, 7: Heat equalization member, 71: Cylindrical body, 72: Wall, 73: Opening, 8: Support member, 81A: First arm, 81B: Second arm, 82: Base, 821: Base material, 822: Holding part, 9: Housing

Claims

1. A thermal analysis apparatus comprising: a heating furnace having a cylindrical heating section; a first sample holder and a second sample holder disposed within the heating section; a detection section configured to detect at least one of the weights of the first sample holder and the second sample holder, and the temperature difference between the first sample holder and the second sample holder; a heat-soothing member disposed within the heating section so as to cover at least a portion of the first sample holder and the second sample holder; and a support member for supporting the heat-soothing member, wherein the support member extends from outside the heating section to the holding position of the heat-soothing member.

2. A thermal analysis apparatus according to claim 1, wherein the heat equalization member is arranged at a distance from the inner surface of the heating section.

3. A thermal analyzer according to claim 1 or claim 2, wherein the heat soaking member has a cylindrical body that covers the first sample holder and the second sample holder from the radially outer side of the heating section.

4. A thermal analyzer according to any one of claims 1 to 3, wherein the heat soaking member has a wall that covers at least a portion of the first sample holder and at least a portion of the second sample holder in the axial direction of the heating section.

5. A thermal analyzer according to claim 4, wherein the wall has an opening.

6. A thermal analyzer according to any one of claims 1 to 5, wherein the first sample holder and the second sample holder are not physically connected within the heating section.

7. A thermal analysis apparatus according to any one of claims 1 to 6, wherein the thermal conductivity of the support member is less than the thermal conductivity of the heat-soothing member.

8. A thermal analysis apparatus according to any one of claims 1 to 7, wherein the heating furnace is a resistance heating furnace.

9. A thermal analyzer according to any one of claims 1 to 8, wherein the detection unit has at least one of a thermocouple and a balance beam, the heat equalization member has a metal plate, and the support member has a rod-shaped member extending along the axial direction of the heating unit.

10. A thermal analysis method comprising the step of detecting at least one of the weights of the first sample holder and the second sample holder, and the temperature difference between the first sample holder and the second sample holder, while heating a heating unit in which a first sample holder containing a sample and a second sample holder containing a standard sample are arranged, wherein a heat-sensing member is arranged inside the heating unit to cover at least a portion of the first sample holder and the second sample holder, and the heat-sensing member is supported by a support member that extends from outside the heating unit to the holding position of the heat-sensing member.

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