JP2008238090A - Microflow channel body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a microflow channel body capable of heating the fluid flowing through a flow channel to a predetermined temperature. <P>SOLUTION: The microflow channel body 1 is equipped with the flow channel 2a provided in a substrate 2 to permit a fluid to flow, the first heater 3a provided to the first region adjacent to the flow channel 2a and the second heater 3b adjacent to the flow channel 2a through a first region and provided to a second region wider than the first region. The fluid flowing through the flow channel 2a can be heated to a predetermined temperature, the large heat stress caused by thermal expansion difference is hard to occur between a heater forming region and a heater non-forming region and damage such as a crack or the like is hard to be produced in the substrate 2. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a microchannel body having a microchannel inside, and in particular, a micromixing device (micromixer) that mixes a plurality of fluids in a microchannel, and microheat exchange that heats and cools a fluid The present invention relates to a microchannel body used in devices and microchemical devices such as microreaction devices (microreactors) that perform chemical, biochemical and physicochemical reactions.

Conventionally, in a micro-channel body provided with a channel for flowing a fluid inside a ceramic substrate, a heater in which a conductive material for heating the channel is arranged in a meandering shape is formed inside the substrate. Some have supplied heat to the flow path (see, for example, Patent Document 1 below).
Special Table 2002-527254

  However, since the heater that heats the flow path heats only a part of the micro flow path body, depending on the temperature change around the micro flow path body, the heat supplied from the heater may be The fluid that easily escapes to the area other than the heating section may not be heated to a predetermined temperature, and the expected reaction result cannot be stably obtained.

  In addition, in the conventional microchannel body, when the heating temperature by the heater is increased, a large temperature difference is generated between the heater formation region and the heater non-formation region, and the heater formation region and the heater non-formation region are between. In this case, a thermal stress due to a difference in thermal expansion occurs, and in extreme cases, the thermal stress may cause breakage such as cracks in the ceramic substrate. In this case, the problem that the fluid leaks from the flow path occurs.

  The present invention has been devised in view of the above problems, and an object thereof is to provide a micro-channel body that can heat a fluid flowing in the channel to a predetermined temperature.

  The microchannel body of the present invention includes a channel provided inside the base body through which a fluid flows, a first heater provided in a first region adjacent to the channel, and the first region. And a second heater provided in a second region adjacent to the flow path and wider than the first region.

  Preferably, in the microchannel body of the present invention, the first heater generates heat at a higher temperature than the second heater.

  Preferably, in the microchannel body according to the present invention, the first heater and the second heater are formed by meandering conductive members so as to be folded along the channel. And

  Preferably, in the microchannel body according to the present invention, the first heater and the second heater are arranged in a meandering shape with a conductive member so as to intersect the extending direction of the channel. It is characterized by that.

  Preferably, in the microchannel body of the present invention, the substrate is made of ceramics.

  Preferably, in the microchannel body of the present invention, the substrate includes 90% by mass or more of alumina.

  Preferably, in the microchannel body of the present invention, the substrate is formed by a ceramic green sheet lamination method.

  The micro-channel body of the present invention includes a channel provided inside the substrate for flowing a fluid, a first heater provided in a first region adjacent to the channel, and the flow through the first region. And the second heater provided in the second region wider than the first region, and the second region is also heated by the second heater, so that the first region is changed to the second region. It becomes difficult for heat to escape, and it becomes easier to control the temperature of the first region around the flow path. As a result, the fluid flowing in the flow path can be heated to a predetermined temperature, and an expected reaction result can be stably obtained.

  Preferably, in the microchannel body of the present invention, when the first heater generates heat at a higher temperature than the second heater, the temperature distribution from the channel to the outer periphery of the microchannel body can be maintained from high temperature to low temperature. It is possible to reduce the thermal stress generated between the heater formation region and the heater non-formation region.

  Preferably, in the microchannel body of the present invention, when the first heater and the second heater are arranged in a meandering shape so that the conductive member is folded along the channel, the first heater And since it becomes easy to adjust the length of the second heater, the heater design is facilitated.

  Preferably, in the microchannel body of the present invention, when the first heater and the second heater are arranged in a meandering shape so that the first member and the second heater intersect with the extending direction of the channel, the number of meanders And the fluid flowing in the flow path can be easily heated.

  Preferably, in the microchannel body of the present invention, when the substrate is made of ceramics, the microchannel body can be made excellent in chemical resistance.

  Preferably, in the microchannel body of the present invention, the substrate contains 90% by mass or more of alumina, so that the mechanical strength is high and the chemical resistance that resists the attack of chemicals such as acid and alkali is very high. An excellent ceramic micro-channel body can be provided.

  Preferably, in the microchannel body of the present invention, when the substrate is formed by a ceramic green sheet lamination method, the channel, the first heater, and the second heater are formed on the ceramic green sheet, respectively. By laminating, a microchannel body having a predetermined shape can be easily formed, and a microchannel body with high manufacturing efficiency can be provided.

  The microchannel body of the present invention will be described in detail below. FIG. 1A is a perspective view showing an example of an embodiment of a microchannel body of the present invention, and FIG. 1B is a perspective view showing another example of an embodiment of a microchannel body of the present invention. is there. FIGS. 2A and 2B are plan views showing still other examples of the embodiment of the microchannel body of the present invention. FIG. 3 is an exploded perspective view showing still another example of the embodiment of the microchannel body of the present invention. In these figures, 1 is a microchannel body, 2 is a substrate, 2a is a channel, 2b is an inlet, 2c is an outlet, 3a is a first heater, and 3b is a second heater.

  As shown in FIGS. 1 (a) and 1 (b), the microchannel body 1 of the present invention is provided with a channel 2a through which a fluid is circulated in a base 2, and a first region around the channel 2a. The first heater 3a is provided so as to be parallel to the flow path 2a, and the second area adjacent to the first area and adjacent to the flow path 2a through the first area has a larger area than the first area. A second heater 3b is provided. For example, in a plan view of the microchannel body 1, the second region is positioned behind the first region so as to overlap the first region through the channel 2 a, and the first region provided in the first region In the back of the heater 3a, the second heater 3b is provided in a larger area than the first heater 3a.

Here base 2, alumina _(Al 2 _{O 3)} sintered material, aluminum nitride (AlN) sintered material, mullite _{(3Al 2 O 3 · 2SiO 2} ) sintered material, and ceramics such as glass ceramics, A flow path 2a having a small width through which the fluid to be treated is circulated is formed inside the substrate 2 by an etching method, a cutting method, a molding method using a mold, or the like, which is made of glass, quartz, Si, metal, resin, or the like. Has been. An inflow port 2b and an outflow port 2c for allowing the fluid to be treated to flow into the flow path 2a are formed.

  The inflow port 2b and the outflow port 2c are provided in a through-hole shape between the outside and the channel 2a so that the channel 2a can be connected to the outside. For example, as shown in FIG. A through hole is provided on the surface of the base 2, or provided inside a cylindrical portion 2 d that protrudes from the surface of the base 2 together with the base 2 as shown in FIG. In FIG. 1B, an opening of the inflow port 2b or the outflow port 2c is formed on the surface of the cylindrical portion 2d so that fluid can flow in or out from the outside, and the other end of the inflow port 2b or the outflow port 2c. Is connected to the flow path 2a. Further, the cylindrical portion 2d is formed into a polygonal cylindrical shape in whole or in part for the purpose of preventing the rotation of the external connection tube or the like so that the external connection tube can be inserted into the outer peripheral surface. The base 2 and the cylindrical portion 2d may be appropriately selected from materials that are not affected by the fluid to be processed.

  As shown in FIG. 1B, when the inflow port 2b for injecting fluid into the flow path 2a or the outflow port 2c for outflowing is a cylindrical part 2d protruding from the surface of the base body 2 integral with the base body 2, The inflow port 2b and the outflow port 2c can be connected to predetermined positions with respect to the flow path 2a. In addition, the inner peripheral surface of the external connection tube can be fitted to the outer peripheral portion of the cylindrical portion 2d for a required length, and the external connection tube can be securely fixed to a predetermined position of the microchannel body 1. it can. Thereby, the pressure loss generated at the inlet 2b and the outlet 2c when flowing the fluid can be reduced. Even if the microchannel body 1 is thin, the external connection tube can be firmly fixed. As a result, even when a chemical reaction or the like is performed in the flow path 2a, the inflow port 2b and the outflow port 2c do not become singular points of pressure loss, and an expected reaction result can be stably obtained. Can do.

  The base 2 is provided with a first heater 3a in a first area around the flow path 2a, and the plane of the micro flow path body 1 is in a plane orthogonal to the direction connecting the flow path 2a and the first area. The surface of the second region that overlaps the first region and is wider than the first region in view is provided, and the second heater 3b is provided in the surface of the second region.

  With this configuration, the second region is also heated by the second heater 3b, and the temperature difference gradient between the flow path 2a and the second region can be reduced, so that heat escapes from the first region to the second region. This makes it difficult to control the temperature of the first region around the flow path 2a. As a result, the fluid flowing in the flow path 2a can be heated to a predetermined temperature, and an expected reaction result can be stably obtained.

  In addition, with the above configuration, the first region is provided with the first heater 3a and the second heater 3b and is maintained at a high temperature, and the second region is provided with the second heater 3b and is more than the first region. Keep it at a low temperature. That is, in the first region around the channel 2a, the fluid flowing in the channel 2a is set to a temperature at which the fluid can be heated to a predetermined temperature, and heat from the first region is difficult to escape in the second region outside the channel 2a. Thus, the first region, the second region, and the second region are maintained at a temperature lower than that of the first region, and lower than that of the second region outside the second region. The temperature distribution is such that the temperature decreases sequentially in the order of the outside of the region. Therefore, the temperature gradually decreases as the center side of the micro-channel body 1 in the flow channel 2a formation region increases toward the outside at a high temperature, and a large temperature difference does not occur between the heater formation region and the heater non-formation region. In addition, a large thermal stress is hardly generated due to a difference in thermal expansion between the heater forming region and the heater non-forming region, so that the base member 2 is not easily damaged such as a crack. As a result, it is possible to prevent fluid from leaking from the flow path 2a.

  Further, the temperature of the second heater 3b is preferably set to a temperature higher than the temperature of the second region reached by being heated by the first heater 3a when only the first heater 3a is turned on. As a result, the temperature gradient between the first region and the second region becomes gentler than in the case where the second heater 3b is not provided, and the first region can be easily kept warm. Further, since the area of the second region is larger than the area of the first region and the heat capacity of the second region is larger than the heat capacity of the first region, the temperature change of the first region can be made small.

  The first heater 3a and the second heater 3b are formed of a conductive member, and both ends of the first heater 3a and the second heater 3b are drawn out to the surface of the base 2, and the both ends are respectively connected to the outside. The first heater 3a and the second heater 3b generate heat by functioning as a heater by flowing an electric current connected to an electric circuit. As the conductive members to be the first heater 3a and the second heater 3b, those made of a metal wire or metal foil made of nichrome (Ni—Cr alloy) or the like, tungsten (W), molybdenum ( It may be formed by a metallized layer made of a refractory metal such as Mo) or manganese (Mn).

  As described above, the channel 2a, the inlet 2b, the outlet 2c, the first heater 3a, and the second heater 3b are formed on the base body 2, whereby the microchannel body 1 is configured.

  Here, the channel 2 a is provided as a minute channel having a minute width of 5 to 500 μm and a rectangular section of 5 to 500 μm. The cross section of the flow path 2a may be circular, triangular or other polygonal.

  The microchannel body 1 obtained in this way is, for example, a microchannel that performs chemical, biochemical, or physicochemical reactions in which the fluid is heated or cooled in the channel 2a, or the fluids are mixed and reacted. It can be suitably used for a chemical chip, a reformer that reforms alcohol into hydrogen, and the like.

  As for the arrangement of the flow path 2a, for example, as shown in FIG. 1A, an inflow port 2b and an outflow port 2c are provided one by one, and the flow path 2a is formed so as to connect the inflow port 2b and the outflow port 2c. Or a plurality of inlets 2b and outlets 2c provided at two or more locations as shown in FIG. 1 (b) and connected to the plurality of locations 2b. The flow paths 2a may be merged in a predetermined order, and may further be branched into a plurality of flow paths 2a from the flow path 2a toward the outlet 2c. The flow path 2a may be arrange | positioned at linear form, and may be arrange | positioned at curvilinear form. Moreover, you may meander like the meander like the 1st or 2nd heater 3a, 3b. The arrangement of the flow path 2a is not limited to the form shown in FIGS. 1A and 1B, and can be various forms according to the purpose.

  Here, the first heater 3a preferably has a heater performance that generates heat at a higher temperature than the second heater 3b. Thereby, the flow path 2a part through which the fluid to be heated flows can be heated to a high temperature.

  Preferably, as shown in FIGS. 1 (a), 1 (b), 2 (a), and 2 (b), the first heater 3a and the second heater 3b have S-shaped conductive members. It is good to arrange | position in the meandering shape so that it may fold in the shape which continued. With this configuration, heat is easily generated in the meandering portion, and the heating performance of the first heater 3a and the second heater 3b can be improved.

  As shown in FIG. 2A, the first heater 3a and the second heater 3b are arranged in a meandering shape so that the conductive member folds along the flow path 2a. Alternatively, as shown in FIGS. 1A, 1B, and 2B, the conductive portions are arranged in a meandering shape so as to intersect the extending direction of the flow path 2a. The extending direction of the flow path 2a refers to the direction in which the flow path 2a is viewed as a whole. For example, when the flow path 2a is arranged linearly as shown in FIGS. 1 and 2, the direction connecting the inlet 2b and the outlet 2c can be considered as the extending direction. Even when arranged in a meandering manner so as to cross the extending direction a plurality of times, the extending direction of the entire flow path 2a may be considered as a direction connecting the inlet 2b and the outlet 2c.

  As shown in FIG. 2A, when the conductive member is arranged in a meandering shape so as to be folded back at the end of the flow path 2a along the flow path 2a, the length of the conductive member is set to an appropriate length. Since the adjustment becomes easy, the heater design is facilitated and the flow path 2a is easily heated uniformly along the flow path 2a.

  Preferably, as shown in FIGS. 1 (a) and 1 (b), the conductive member meanders so that the first heater 3a and the second heater 3b intersect the extending direction of the flow path 2a. Arranged in shape. With this configuration, a certain range around the flow path 2a can be heated, and the fluid flowing in the flow path 2a can be easily heated uniformly. Further, by increasing the number of meanders, the fluid flowing in the flow path 2a can be easily heated.

  Although not shown, when the first heater 3a and the second heater 3b are formed of a metal foil or a metallized layer, they may be formed in a flat plate shape, or the first heater 3a and the second heater 3b. May be formed in a coil shape, and the first heater 3a and the second heater 3b may have various shapes.

  Preferably, as shown in FIG.2 (b), the periphery of the connection part with the external electric circuit of the 1st heater 3a and the 2nd heater 3b should be formed wide. With this configuration, the periphery of the connection portion that does not need to function as a heater can be wide to reduce the resistance value so as not to generate heat, so that power is not consumed around the connection portion. And it becomes possible to generate heat efficiently only with the remaining part excluding the periphery of the connection part of the first heater 3a and the second heater 3b. Further, the connection portion can be easily connected to the external electric circuit board.

Preferably, the substrate 2 is made of ceramics. The specific ceramic forming the substrate 2, _Al 2 _{O 3} sintered material, AlN sintered _material, 3Al ₂ O 3 · 2SiO ₂ sintered material, glass ceramics and the like. With this configuration, the microchannel body 1 having excellent mechanical strength, heat resistance, pressure resistance, and chemical resistance can be obtained.

  Preferably, the base 2 contains 90% by mass or more of alumina. With this configuration, the ceramic micro-channel body 1 having high mechanical strength and excellent chemical resistance that can withstand corrosion of chemicals such as acid and alkali can be obtained.

  Preferably, the substrate 2 is formed by a ceramic green sheet lamination method.

For example, if the substrate 2 is made of an Al ₂ O ₃ sintered material, it is suitable for raw material powders such as Al ₂ O ₃ , silicon oxide (SiO ₂ ), magnesium oxide (MgO), and calcium oxide (CaO). A mixture of organic binders, solvents, plasticizers, dispersants, etc. is added to form a slurry, and then a ceramic green sheet (ceramic raw sheet) is formed by adopting a doctor blade method and a calender roll method. The ceramic green sheet is manufactured by subjecting a suitable punching process to the flow path 2a and the like, and then laminating a plurality of the green sheets and firing them at a temperature of about 1600 ° C.

  By punching out the ceramic green sheet in the shape of the flow path 2a, the flow path 2a having a predetermined shape can be easily formed, and the micro flow path body 1 with high manufacturing efficiency can be provided.

  In particular, the positional deviation between the punched portions (openings 22a, through holes 21a) by the mold can be suppressed to several tens of μm or less, and the microchannel body 1 with high dimensional accuracy can be obtained.

  Next, an example of the manufacturing method of the microchannel body 1 of the present invention will be described in detail with reference to FIG.

  First, a first ceramic green sheet 21 is prepared as a ceramic green sheet that is the uppermost layer of the substrate 2. This first ceramic green sheet 21 is punched by using a die with a through hole 21a at a location that becomes the inlet 2b and the outlet 2c.

  Next, a second ceramic green sheet 22 to be laminated on the lower side of the first ceramic green sheet 21 is prepared. The second ceramic green sheet 22 is punched by using a die for punching holes that are the side surfaces of the flow path 2a, or a groove that becomes the flow path 2a is processed by a pressing die. The opening 22a of the punching hole or groove is closed so as to be covered by the lower surface of the first ceramic green sheet 21 except for the portion of the first through hole 21a connected to the inflow port 2b or the outflow port 2c.

  Next, a third ceramic green sheet 23 to be laminated on the lower side of the second ceramic green sheet 22 is prepared. The third ceramic green sheet 23 serves to cover the lower opening of the flow path 2a from the lower side and is formed in a flat plate shape.

  Next, a fourth ceramic green sheet 24 to be laminated below the third ceramic green sheet 23 is prepared. The fourth ceramic green sheet 24 is formed in a flat plate shape, and a metal paste obtained by adding and mixing an appropriate organic binder, plasticizer, solvent, etc. to a refractory metal powder such as W, Mo, Mn or the like is screened. The first metallized layer 24a to be the first heater 3a is formed in a predetermined pattern by printing and coating using a thick film forming technique such as a printing method.

  Next, a fifth ceramic green sheet 25 is prepared which is laminated on the lower side of the fourth ceramic green sheet 24 and becomes the lowermost layer. The fifth ceramic green sheet 25 is formed in a flat plate shape, and a metal paste obtained by adding and mixing an appropriate organic binder, plasticizer, solvent, etc. to a refractory metal powder such as W, Mo, or Mn is screened. The second metallized layer 25a to be the second heater 3b is formed in a predetermined pattern by printing and coating using a thick film forming technique such as a printing method.

  Each of the first to fifth ceramic green sheets 21 to 25 is laminated in a predetermined order and fired at a temperature of about 1600 ° C., whereby the substrate 2 is manufactured.

  As described above, the microchannel body 1 made of ceramics can be efficiently manufactured by the ceramic green sheet lamination method.

  In the above example, the first metallized layer 24a serving as the first heater 3a and the second metallized layer 25a serving as the second heater 3b are formed with punched holes or groove openings serving as the flow path 2a. Although the example formed in the ceramic green sheet located below the ceramic green sheet is shown, the ceramic green located above the ceramic green sheet in which the punched hole or groove opening serving as the flow path 2a is formed It may be formed on a sheet. Further, in this case, when the flow path 2a is processed as a groove and does not have a lower opening, the third ceramic formed in a flat plate shape serves to cover the lower opening of the flow path 2a from the lower side. The green sheet 23 may be omitted.

  Note that the present invention is not limited to the above-described embodiment, and various modifications may be made without departing from the scope of the present invention.

  For example, in the above embodiment, the inflow port 2b and the outflow port 2c are provided on the upper main surface of the base body 2, but the side surface or the flow path 2a parallel to the direction in which the flow path 2a of the base body 2 extends. It may be provided on a side surface that intersects the direction in which the crossing extends. In this case, the direction in which the flow path 2a extends and the inflow port 2b or the outflow port 2c can be arranged in parallel, and the pressure loss from the inflow port 2b to the outflow port 2c can be reduced.

  Moreover, at least one of the upper side or the lower side of the flow path 2a may be made of a translucent material. With this configuration, the circulation of the fluid in the flow path 2a can be visually confirmed. Moreover, the fluid in the flow path 2a can be chemically reacted by irradiating light in the flow path 2a.

  Further, the base 2 may be formed of a combination of different materials, for example, the portion where the flow path 2a is formed is made of metal, and the heater forming region is formed of an insulating material such as ceramic or resin.

  Moreover, the metal lead terminal may be joined to the connection part with the external electric circuit of the 1st heater 3a and the 2nd heater 3b, and it becomes easy to connect with an external electric circuit.

  In the description of the above embodiment, the terms “upper, lower, left and right” are merely used to describe the positional relationship in the drawings, and do not mean the positional relationship in actual use.

(A) is a perspective view which shows an example of embodiment of the microchannel body of this invention, (b) is a perspective view which shows the other example of embodiment of the microchannel body of this invention. (A), (b) is a top view which shows the further another example of embodiment of the microchannel body of this invention, respectively. It is a disassembled perspective view which shows the example of the microchannel body of this invention.

Explanation of symbols

1: Microchannel body 2: Base 2a: Channel 2b: Inlet 2c: Outlet 3a: First heater 3b: Second heater

Claims (7)

A flow path through which a fluid provided inside the substrate flows, a first heater provided in a first area adjacent to the flow path, and adjacent to the flow path via the first area, A microchannel body comprising: a second heater provided in a second area wider than one area. The microchannel body according to claim 1, wherein the first heater generates heat at a higher temperature than the second heater. 3. The micro of claim 1, wherein the first heater and the second heater are arranged in a meandering shape with a conductive member so as to be folded back along the flow path. Channel body. The said 1st heater and the said 2nd heater are arrange | positioned in the shape where the electroconductive member meandered so that the extending direction of the said flow path might be crossed, The Claim 1 or Claim 2 characterized by the above-mentioned. The microchannel body described. The microchannel body according to any one of claims 1 to 4, wherein the substrate is made of ceramics. The microchannel body according to any one of claims 1 to 5, wherein the substrate contains 90 mass% or more of alumina. The microchannel body according to any one of claims 1 to 6, wherein the base is formed by a ceramic green sheet lamination method.

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