JP5268095B2 - Member having channel formed on surface, biochip, fuel cell and fuel cell system using the same - Google Patents

Description

  The present invention relates to a member in which a flow path requiring hydrophilicity is formed, and also relates to a biochip, a fuel cell, and a fuel cell system using the member.

  Microsystems such as microreactor systems, electrophoresis microsystems, and centrifuge microsystems have become widely used with recent advances in miniaturization and high-speed assay in chemistry, biology, and medicine. . The fine flow path is used as a liquid flow path for reagents and chemicals in the microsystem, and is an important element that forms the basis of the microsystem.

  Advantages of microsystems are that analysis is generally possible with a small amount of reagents and that the analysis device can be made smaller and lighter, and that integration and parallel processing are possible. In addition, it can be mentioned that contamination of impurities can be prevented. In the micro system, it is essential to make the liquid flow path fine, and many fine flow paths have been proposed.

  Conventionally, the fine flow path in the microsystem is generally formed on a silicon substrate or a glass substrate by using a semiconductor microfabrication technique. In particular, in a highly accurate micro system, variations in the shape, size, cross-sectional area, and flatness of the micro flow channel greatly affect the characteristics and accuracy of the micro system. Thus, for example, the microchannel system affects the reaction rate and reaction volume in a microreactor system, and affects the accuracy of mass spectrometry in a microsystem that performs electrophoresis or centrifugation of DNA, RNA, and protein. give. In addition, the performance of a liquid fuel using such a fine flow path is greatly affected.

  Furthermore, not only the shape of the microchannel but also the characteristics of the surface of the microchannel have become a problem due to the progress of the microsystem. For example, when the cross-sectional area of the fine channel is very small, a phenomenon occurs in which water hardly flows when the surface of the fine channel is hydrophobic compared to when the surface of the fine channel is hydrophilic. Further, as a material for forming the fine flow path in the microsystem, it is desired to use a polymer material such as a plastic or silicone resin that is lightweight and easy to process instead of using a glass member. However, since the hydrophilicity is inferior to that of the glass substrate, there are problems that the flow rate and flow velocity are insufficient, and it is difficult to make the flow path fine. Therefore, when the polymer material is used as a material for forming the fine flow path in the microsystem, hydrophilicity has been improved by applying a hydrophilic treatment to the fine flow path and its entrance / exit.

  The following methods have been proposed as conventional methods for improving hydrophilicity. For example, a hydrophilic film is formed on the surface of the flow path as in Patent Document 1 (Japanese Patent Laid-Open No. 8-138692), or a hydrophilic property such as plasma treatment as in Patent Document 2 (Patent Document WO 99/40642). A method of processing has been proposed.

  However, in the method of forming a hydrophilic film on the surface of the flow path, there is a high possibility that the hydrophilic film is peeled off from the surface of the flow path, and the hydrophilic film is formed during use of the microsystem having the flow path. It may elute gradually. Further, there is a possibility that the hydrophilic film cannot be uniformly formed in the fine channel, or that the worst channel is filled with the hydrophilic film. In addition, since the fine channel becomes thicker at least by the thickness of the hydrophilic coating, it is not suitable for application to a small micro system.

Also, when hydrophilic treatment is performed by surface treatment such as plasma treatment, there is little concern as in the case of forming the hydrophilic coating, but the hydrophilicity gradually decreases with time, and the hydrophilicity is maintained for a long time. It was difficult.
Japanese Patent Laid-Open No. 8-138692 WO99 / 40642 pamphlet

  The present invention has been made to solve the problems of the prior art as described above, and provides a member having a flow path with improved hydrophilicity and imparted stable hydrophilicity, and It aims at providing the small apparatus using the said member.

  The present invention is a member made of a polymer having a channel formed on the surface thereof, and a member having a hydrophilic region in which at least a part of the surface of the wall surface constituting the channel is made hydrophilic by ion implantation About.

  In the member of the present invention, it is preferable that at least a part of the surface of the wall surface constituting the flow path further has a hydrophobic region.

  In the member of the present invention, carbon ions are preferably implanted by ion implantation.

  In the member of the present invention, it is preferable that negative ions are implanted by ion implantation.

  In the member of the present invention, the implantation energy in the ion implantation is preferably 1 keV or more and 100 keV or less.

In the member of the present invention, the ion implantation amount in the ion implantation is preferably 1 × 10 ¹⁴ ions / cm ² or more and 1 × 10 ¹⁷ ions / cm ² or less.

  Further, the member of the present invention is preferably exposed to an oxidizing atmosphere after ion implantation.

  In the member of the present invention, it is preferable that plasma treatment or ozone treatment is performed after ion implantation.

The present invention also relates to a biochip using the above-described member.
The present invention also relates to a fuel cell using the above-described member.

  The present invention also provides a fuel cell system using the above-described fuel cell, comprising a fuel cell, an oxygen supply unit, a fuel supply unit, a fuel tank, an air tank, and a manual pump, and supplies oxygen. Is connected to an oxygen supply port and an air tank in the fuel cell. The fuel supply unit is connected to a fuel supply port and a fuel tank in the fuel cell. The air tank is further connected to a manual pump. The fuel tank system is connected, and the air tank and the fuel tank are related directly or indirectly.

  Further, in the fuel cell system of the present invention, the pressure in the fuel tank is adjusted at the connecting portion that directly or indirectly connects the air tank and the fuel tank and / or the gas discharge portion that is connected to the fuel tank. It is preferable that a pressure regulating valve is further provided, and a regulator is further installed in the air supply unit.

  In the fuel cell system of the present invention, the fuel tank is preferably provided at a position where fuel can be supplied substantially parallel to the in-plane direction of the electrolyte membrane of the fuel cell.

  It is possible to provide a member having a flow path with improved hydrophilicity and stable hydrophilicity. Moreover, a biochip capable of quickly mixing a sample and a reagent can be provided by using the member. Moreover, a fuel cell having a large output can be provided by using the member.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following drawings, the same or corresponding parts are denoted by the same reference numerals, and description thereof will not be repeated. In addition, dimensional relationships such as length, size, and width in the drawings are changed as appropriate for clarity and simplification of the drawings, and do not represent actual dimensions.

<First Embodiment: Member>
≪Structure≫
FIG. 1 is a cross-sectional view of one embodiment of a member in the present invention. 2A is a cross-sectional view taken along line IIA-IIA in FIG. FIG. 2B is a cross-sectional view of one embodiment showing another aspect of the member of the present invention. FIG. 3 is a cross-sectional view of an embodiment representing another aspect of the member of the present invention. Hereinafter, description will be given with reference to FIGS.

  First, it demonstrates based on FIG. 1 and FIG. 2A. The present embodiment is a member 210 made of a polymer having a channel 206 formed on the surface thereof, and at least a part of the surface of the wall surface constituting the channel 206 is made hydrophilic by ion implantation. It has a conversion area 205. Further, as in the present embodiment, the member 210 may be provided with a lid 207 with respect to the substrate 201, and the flow path 206 is formed by the substrate 201 and the lid 207, or may be composed only of the substrate 201, for example. . And it is preferable that at least one part of the surface of the wall surface which comprises the flow path 206 has a hydrophobic area | region. Here, in the embodiment shown in FIG. 2A, the lid 207 is a hydrophobic region. As shown in FIG. 2B, in addition to the lid 207, a hydrophobic region 208 may be provided on at least a part of the surface of the wall surface constituting the flow path 206 formed in the substrate 201. In addition to the flow path 206, the member 210 can include a chamber 202 for holding liquid and gas. A hydrophilic region and a hydrophobic region can be appropriately provided on the surface of the wall surface constituting the chamber 202 as well.

  Here, the form of the member 210 is not particularly limited as long as it is made of a high molecular polymer, and there is no problem in this embodiment as long as the channel 206 is formed on the surface. Although the dimension of the flow path 206 is not specifically limited, For example, it is easy to produce a flow path with a width of about 200 to 10 μm and a depth of about 200 to 1 μm as a fine flow path for liquid. In principle, it is possible to miniaturize to the minimum processing dimension of semiconductor microprocessing. Therefore, in the present invention, it is possible to cope with a fine structure in which it is difficult to impart hydrophilicity by a conventional coating method. In the embodiment shown in FIG. 3, the lid 207 is a hydrophobic region. The “polymer” in the present embodiment includes a polymer compound other than an inorganic material in a broad sense. Specifically, examples of the synthetic resin include a thermosetting resin, a thermoplastic resin, a plastic, and a natural resin. More specifically, examples of the polymer include silicon resin PDMS (polydimethylsiloxane), polystyrene, polyimide, polylactic acid, and silicone rubber.

  Further, as shown in FIGS. 2A, 2B, and 3, the cross-sectional shape of the flow path 206 is not particularly limited as long as the liquid and the gas can flow. However, it is preferable that the cross section is a rhombus or a circle like the channel 206 shown in FIG. This is because the hydrophilic region can be uniformly formed on the substrate 201 by the ion implantation described above.

  Compared with a glass member having a conventional flow path, the member 210 according to the present embodiment is light in weight and less susceptible to breakage. Therefore, the width of a small apparatus using the member can be increased. In addition, the member 210 of the present embodiment can improve the hydrophilicity and durability without increasing the thickness as compared with a conventional hydrophilic member or the like. And the flow path 206 in this embodiment can flow a liquid and gas efficiently even if it is fine.

<< Operation >>
In the flow path 206 formed by the present embodiment, liquid and gas can flow. In the channel 206, the gas efficiently flows along the hydrophobic region, and the liquid flows along the hydrophilic region. By causing such an operation, even if the flow path 206 is fine, the liquid can move efficiently through the flow path 206. Further, even if a gas is mixed into the liquid in the flow path 206 for some reason such as generation of bubbles, the gas can be efficiently discharged from the liquid and moved.

≪Manufacturing method≫
First, a high molecular polymer to be the member 210 is prepared. And the flow path 206 and the chamber 202 are formed in the surface by a well-known method suitably. Next, the surface of the member 210 is washed and dried. And the hydrophilicity area | region which improved the hydrophilic property of this flow path 206 surface by ion-implanting, maintaining the clean state with respect to the surface of the wall surface which comprises this flow path 206 and the chamber 202 in the member 210 Can be formed. In addition, the durability of the hydrophilic region can be improved as compared with the conventional method.

  Here, in the ion implantation, it is preferable to implant carbon ions. This is because when the member 210 is used for a biochip or the like described later, the adverse effect of the biochip on the sample is small. Specifically, when the member 210 when ion implantation of heavy metal ions such as silver ions is used for a biochip as described later, the silver ions and the like are eluted, and the eluted silver ions are This is because the sample may be adversely affected. Also, the carbon ions implanted into the member 210 can exist more stably with respect to the member 210 than other metal ions. Even if it is eluted from the member 210, there are few problems when it is used in a fuel cell or biochip described later using the member 210.

  In the ion implantation, negative ions are preferably implanted. This is because, compared to the case where ions are implanted using positive ions, the generation of defective products due to damage to the member 210 and variations in hydrophilicity is much less when ions are implanted using negative ions. It is. Specific examples of the negative ions include carbon negative ions, gold, silver, platinum, titanium, vanadium, chromium, manganese, cobalt, zinc, indium, tungsten, aluminum, silicon, germanium and the like depending on the purpose. Examples of the metal and semiconductor elements include negative ions.

  In the ion implantation, the implantation energy is preferably 1 keV or more and 100 keV or less, and more preferably 5 keV or more and 30 keV or less. When the injection energy is less than 1 keV, almost no hydrophilization is observed in the flow path 206, and even if the injection energy exceeds 100 keV, it is difficult to confirm the improvement of the hydrophilic effect, and the member 210 is deteriorated or broken. This is because it can be seen.

In this embodiment, the ion implantation amount in the ion implantation is preferably 1 × 10 ¹⁴ ions / cm ² or more and 1 × 10 ¹⁷ ions / cm ² or less, preferably 5 × 10 ¹⁴ ions / cm ² or more and 5 × 10 5. It is particularly preferably ¹⁶ ions / cm ² or less. When the ion implantation amount is less than 1 × 10 ¹⁴ ions / cm ² , almost no hydrophilization is observed in the flow path 206, and when the ion implantation amount exceeds 1 × 10 ¹⁷ ions / cm ^2. This is because the surface becomes so rough that the liquid flow may be hindered or the surface may be sputtered. Furthermore, in the channel 206 of this embodiment, it is preferable that the concentration of the element implanted at a depth of 30 to 70 μm from the surface is about 5 × 10 ¹⁸ ions / cm ³ to 1 × 10 ²² ions / cm ³ . This is because at this concentration, hydrophilicity and durability are improved. Moreover, a well-known method can be used about the above-mentioned ion implantation.

  The member 201 is preferably exposed to an oxidizing atmosphere after ion implantation. When exposed to an oxidizing atmosphere after ion implantation, the hydrophilicity and durability of the member 210 are further enhanced. The oxidizing atmosphere refers to an atmosphere of oxygen, nitrogen oxide, hydrogen chloride, or the like, and is preferably an ozone atmosphere. This is because, in the case of using ozone, desired hydrophilic improvement can be obtained by a short time and low temperature treatment.

  Further, the member 201 is more preferably exposed to plasma or ozone after ion implantation. Examples of the plasma include atmospheric plasma and plasma in O2. The member 201 exposed to plasma or ozone is further improved in hydrophilicity and durability.

  Here, the contact angle measurement method can be used for the evaluation of hydrophilization in the present invention. In the present invention, the hydrophilized region means that the contact angle measurement method results in a decrease in the contact angle compared to before treatment, and the hydrophobic region means that the contact angle is smaller than that before treatment. It is defined that the result is equivalent or better. In the material used in this embodiment, the contact angle before processing was about 100 to 90 °. When the hydrophilicity / hydrophobicity of the original material is not known, the hydrophilicity / hydrophobicity may be divided according to whether the contact angle is less than 90 ° or more. Moreover, in the following embodiment, the member mentioned above can be utilized suitably.

<Second Embodiment: Biochip>
FIG. 4 is a schematic plan view showing only a part for easy understanding of a biochip using the member according to the present invention. FIG. 5 is a view showing a cross section taken along line VV in FIG. 4 and a lid. FIG. 6 is a plan view showing an extracted part of a biochip according to another aspect of the present embodiment.

  The biochip in this embodiment uses a member as described in the first embodiment. That is, on the surface of the member, in addition to the flow path as described above, a hole or a groove for holding the liquid may be formed. Moreover, it is preferable that the wall surface which forms this hole, a groove | channel, etc. is made into the hydrophilization area | region by the same method as the above-mentioned.

  First, it demonstrates based on FIG. 4 and FIG. In the biochip of this embodiment, in the member 110 made of a polymer, the chamber 103 and the chamber 105 for injecting a liquid containing a test agent or a test substance into the substrate 101, and the test drug and the test substance Is provided. A channel 104 for spatially connecting the chamber 103 and the chamber 102 is formed between the chamber 103 and the chamber 102. A channel 106 is formed to spatially connect the chamber 105 and the chamber 102. Further, as shown in FIG. 5, a lid 107 is provided on the substrate 101. In the present embodiment, the substrate 110 and the lid 107 constitute the member 110. For example, the member 110 includes a member that does not include the lid 107 and is formed only of the substrate 101.

  In the biochip in the present embodiment, it is preferable that the surfaces of the chamber 102, the chamber 103, and the chamber 105, the flow path 104, and the flow path 106 become hydrophilic regions by the above-described hydrophilic treatment.

  As shown in FIG. 5, it is preferable to cover part or all of the flow path 106 and the chamber 102 with a lid 107 or the like as necessary from the viewpoint of preventing intrusion of unnecessary substances such as dust and bacteria. In this embodiment, at least a part of the chamber 105 is not covered with the lid 107, and a hole 108 into which a liquid can be poured is opened. The lid 107 has a hole 109 at a location corresponding to the chamber 102 connected to the chamber 105 via the flow path 106. It is also possible to put the object to be inspected directly into the chamber 105 or the chamber 102 from these holes 108 or 109. Further, in the biochip, the fluid can flow smoothly into the flow path 106 when the holes 108 and 109 are provided. Further, the flow rate in the flow path can be adjusted or increased by sucking the fluid from the holes 108 and 109 with a small pump. As a result, it is possible to keep the chemical solution supplied from the flow path 106 to the chamber 102 at an appropriate flow rate, shorten the inspection time, and improve inspection efficiency. It is also possible to apply pressure to the hole 108 opened in the chamber 105 with a small pump and pump the chemical solution or the like introduced into the chamber 105. In this case, the liquid may be ejected from the hole 109 or the liquid may flow backward from the chamber 102 toward the chamber 103. Therefore, a waste liquid recovery device for preventing scattering of liquid or the like is connected from the hole 109. It is preferable.

  In this embodiment, the test agent and the substance to be inspected are put into the chambers 103 and 105 different from the chamber 102 in which both are mixed and flow into the chamber 102 through the fine flow path. Alternatively, either one of the substances to be inspected may be provided, and the other may be introduced from the chamber 103 or the chamber 105 through the channel 104 or the channel 106.

  FIG. 6 shows a part of a biochip according to another aspect of the present embodiment, and shows a configuration in which chambers and flow paths that are not used or actually used in FIG. 4 are omitted. When two liquids or more are used for the substance to be inspected and the test drug, it is possible to add a chamber and a flow path to the biochip shown in FIG.

  FIG. 7 is a cross-sectional view of a portion of a biochip according to another aspect of the present embodiment. FIG. 8 is a cross-sectional view of a portion of a biochip according to another aspect of the present embodiment. Hereinafter, a description will be given based on FIGS. 7 and 8.

  As shown in FIG. 7, it is preferable that the liquid is inclined toward the inflow direction because the liquid can easily move in the flow path. In the structure shown in FIG. 7, the chamber 102 side as the liquid outlet is wider in the thickness direction than the chamber 105 side as the liquid inlet. In the case of the structure shown in FIG. 7, the gas is smoothly discharged into the hole 109, there is little gas moving in the reverse direction from the chamber 102 to the chamber 105, and the liquid smoothly flows from the chamber 105 to the chamber 102. be able to. In addition, the biochip shown in FIG. 7 has an advantage that it is easy to manufacture because the channel 106 has no inclined surface.

  In addition, as shown in FIG. 8, the bottom surface of the flow path 106 may be inclined from the chamber 105 to the chamber 102. The biochip shown in FIG. 8 can fill the chamber 102 with a liquid.

In the biochip of the present embodiment, erroneous test results can be shown very little. Here, if the ion implantation amount described above is small or the ion implantation depth is too deep, the effect is reduced. Therefore, it is preferable that the implantation energy is 30 keV or less and the implantation amount is 1 × 10 ¹⁴ ions / cm ² or more because the effect is increased. Even if the injection amount exceeds 1 × 10 ¹⁷ ions / cm ² , the effect is not increased so much, and the surface is too rough, so that the injection amount is 1 × 10 ¹⁴ ions / cm ² to 1 × 10 ¹⁷ ions / cm ^2. preferable. In addition, in the biochip, it is particularly preferable that the injection amount is 5 × 10 ¹⁶ ions / cm ² or less with a safety margin.

  In one form of the inspection chip of the present invention, it is preferable that Ag ions or Ti ions are implanted in regions other than 102 to 106. As the ion implantation, negative ion implantation is preferable as described above. Further, it is preferable to perform a step of exposing to an oxidizing atmosphere. As a result, even if a sample adheres to an unneeded location or dust adheres, the growth of miscellaneous bacteria and the like can be suppressed, so that erroneous test results can be suppressed. .

  According to the biochip of this embodiment, the sample and the reagent can be quickly mixed, so that the inspection can be completed efficiently. In addition, according to the biochip of this embodiment, only a place where a sample or reagent is to be placed or flowed can be made hydrophilic. In addition, it is possible to inactivate samples and reagents attached to unnecessary places. Therefore, it is difficult to cause a problem even when dust adheres to the chip or the chip is reused. Therefore, it is possible to prevent an erroneous inspection result from being obtained.

<< Third embodiment: Fuel cell >>
FIG. 9A is a schematic cross-sectional view of a part of a fuel cell using a member according to the present invention. FIG. 9B is a schematic plan view of a wall surface constituting a flow path in the fuel cell shown in FIG. 9A. 10A and 10B are schematic cross-sectional views of a portion of the flow path in the fuel cell shown in FIG. 9A. Hereinafter, a description will be given based on FIGS. 9A to 10B.

  First, the configuration of the fuel cell according to the present invention will be described with reference to FIG. 9A. An electrolyte membrane 503 capable of selectively transmitting protons is sandwiched between the fuel electrode 504 and the oxidant electrode 502. The fuel electrode 504 is in contact with a flow path 505 to which methanol as liquid fuel is supplied and carbon dioxide as exhaust gas is discharged. The channel 505 is formed by a wall surface 515 and a wall surface 525. The oxidant electrode 502 is in contact with a flow path 501 through which oxygen is supplied and water is discharged. The channel 501 is formed by a wall surface 511 and a wall surface 521. That is, in the present embodiment, the flow path 505 is formed by the wall surface 515 and the wall surface 525, and the wall surface 515 and the wall surface 525 correspond to the members described in the first embodiment. The flow path 501 is formed by the wall surface 511 and the wall surface 521, and the wall surface 511 and the wall surface 521 correspond to the members described in the first embodiment.

  The wall surface on the side where the flow path 501 is in contact with the fuel electrode 504 or the oxidant electrode 502 is partially or entirely removed to be open and connected to the fuel electrode 504 or the oxidant electrode 502. The total area of the walls to be removed is preferably within a range in which the structural strength and the like are maintained, so that a wider one can supply more fuel and oxygen. In the present embodiment, as shown in FIG. 9B, a part of the wall surface 525 constituting the flow path 505 is removed at a plurality of positions, and an opening is provided. Similarly, a part of the wall surface 521 constituting the flow path 501 is also removed at a plurality of positions and has an opening. Although the opening is shown as an example of a quadrangle, other shapes such as a circle may be used. In addition, the size of the opening can be, for example, 100 μm to 0.01 μm on one side.

  In the present embodiment, as shown in FIG. 10A, it is preferable that the wall surface configuring the flow path 505 has a hydrophilic region and a hydrophobic region. In the present embodiment, at least the wall surface 525 on the fuel electrode 504 side in the flow path 505 is hydrophilized to form a hydrophilized region. At this time, since the wall surface 525 is on the side in contact with the fuel electrode 504, it is preferable that the wettability with a liquid fuel such as methanol is high. Furthermore, it is preferable that at least the wall surface near the exhaust port of the wall surface 515 opposite to the fuel electrode 504 is a hydrophobic region. Furthermore, in the case of the fuel cell shown in FIG. 9, it is preferable that the wall surface 515 opposite to the fuel electrode 504 has higher wettability to the liquid fuel on the liquid fuel supply side than on the exhaust gas discharge side. In particular, in the present embodiment, when methanol is used as the liquid fuel, it is preferable that the hydrophilicity of the hydrophilic region is higher.

  Moreover, in this embodiment, as shown to FIG. 10B, it is preferable that the wall surface which comprises the flow path 501 has a hydrophilic region and a hydrophobic region. In the present embodiment, it is preferable that at least the wall surface 521 on the oxidant electrode 502 side in the flow channel 501 is a hydrophobic region. Furthermore, it is preferable that at least the wall surface near the water outlet of the wall surface 511 opposite to the oxidant electrode 502 is hydrophilized. In the case of the fuel cell shown in FIG. 9, it is preferable that the water discharge side of the wall surface 511 opposite to the oxidant electrode 502 has higher hydrophilicity than the oxygen supply side. Thereby, it can suppress that this water blocks the flow path 501 and causes malfunction. Therefore, the fuel cell in this embodiment can be used in a cold region. It is also possible to start the fuel cell unit smoothly even when it is cold.

  Here, FIG. 11 is a schematic cross-sectional view of a part of a fuel cell according to another aspect of the present embodiment. As in the fuel cell shown in FIG. 11, the liquid fuel supply port and the water vapor discharge port are provided in the direction of gravity or centrifugal force, that is, in a stationary state, and the exhaust gas discharge port and the oxygen supply port are provided in the upper part. Is preferred. Such a fuel cell can further improve the efficiency of the fuel cell. In the fuel cell of this embodiment, the fuel cell can increase the maximum output and can be miniaturized.

<< Fourth Embodiment: Fuel Cell >>
FIG. 12A is a schematic cross-sectional view of a part of a fuel cell using a member according to the present invention. 12B is a schematic plan view of a wall surface constituting a flow path in the fuel cell shown in FIG. 12A. 13A and 13B are schematic cross-sectional views of a part of the flow path in the fuel cell shown in FIG. 12A. Hereinafter, a description will be given based on FIGS. 12A to 13B.

  In the present embodiment, in addition to the third embodiment described above, a discharge channel 635 is provided on the opposite side of the channel 505 from the fuel electrode 504. More preferably, a flow path 631 is provided on the opposite side of the flow path 501 from the oxidant electrode 502. The wall surface constituting the exhaust gas flow path 635 is hydrophobic. At least the inner wall surface on the fuel electrode 504 side of the flow path 505 is made hydrophilic. Furthermore, it is preferable that at least the inner wall surface on the channel 635 side of the channel 505 is hydrophobic. Moreover, it is preferable that the inner wall of the flow path 631 is made hydrophilic.

  A part of the wall surface 525 and the wall surface 515 constituting the flow path 505 and the flow path 635 is removed at a plurality of positions, and an opening is provided. Similarly, a part of the wall surface 521 and the wall surface 511 constituting the flow path 501 and the flow path 631 are also removed at a plurality of positions, and openings are provided. Although the opening is shown as an example of a circle, other shapes may be used.

  In the present embodiment, the wall surface 515 and the wall surface 511 are preferably hydrophobic regions, and the wall surface 525 and the wall surface 521 are preferably hydrophilic regions. According to this embodiment, compared with the third embodiment, effects such as an efficient reaction of fuel, an efficient supply of fuel, and an efficient exhaust gas discharge can be expected.

  Here, FIG. 14 is a schematic cross-sectional view of a part of a fuel cell according to another aspect of the present embodiment. As in the fuel cell shown in FIG. 14, the liquid fuel supply port and the water vapor discharge port are preferably provided in the direction of gravity or centrifugal force, that is, on the lower side, and the exhaust gas discharge port and the oxygen supply port are preferably provided on the upper side. . Such a fuel cell can further improve the efficiency of the fuel cell. In the fuel cell of this embodiment, the fuel cell can increase the maximum output and can be miniaturized.

«Fifth embodiment: fuel cell»
FIG. 15A is a schematic perspective view of a fuel cell using a member according to the present invention, and FIG. 15B is a diagram schematically showing a part of a cross section taken along line XVB-XVB in FIG. 15A. 16A and 16B are diagrams schematically showing the operation of the fuel cell according to the present embodiment.

  Hereinafter, description will be given based on FIGS. 15A, 15B, 16A, and 16B. In the fuel cell of the present embodiment, the channel 505 and the channel 635 are formed in the member 701, the liquid fuel 710 is supplied from the supply port 708, and the carbon dioxide 711 is discharged from the exhaust port 709. The fuel cell also includes a fuel electrode 706, an electrolyte membrane 705, and an oxidant electrode 707. A wall surface of at least a portion connected to the fuel electrode 706 side of the flow path 505 in which the liquid fuel 710 flows is hydrophilized. The wall surface of at least the portion connected to the fuel electrode 706 side of the flow path 635 from which gas such as carbon dioxide is discharged is hydrophobic. Thereby, the liquid fuel 710 can be supplied efficiently. Further, the liquid fuel 710 can be prevented from flowing out into the flow path 635. In the present embodiment, PTFE (polytetrafluoroethylene) of the porous thin film 704 can be used on the wall surface on the fuel electrode 706 side. Since PTFE is hydrophobic, in this embodiment, the portion that becomes the wall surface of the flow path 505 can be hydrophilized. It is preferable that the other wall surface of the channel 505 is also hydrophilized. The other wall surface of the channel 635 may be hydrophobic, but is preferably hydrophilic so that it can be discharged when a small amount of liquid fuel 710 leaks.

  The width of the opening on the wall surface of the flow path 505 to which the liquid fuel 710 is supplied is preferably larger than the width of the opening on the wall surface of the flow path 635 from which the carbon dioxide 711 and the like are discharged. Accordingly, the liquid fuel 710 can be supplied more efficiently, and the liquid fuel 710 can be prevented from flowing out into the flow path 635 by reducing the pressure difference between the liquid and the gas.

  With such a structure, the supplied liquid fuel 710 flows out from the flow path 505 through the pores of the porous membrane 704 to the fuel electrode 706 as shown by an arrow 702. The fuel cell reacts with a so-called MEA (membrane electrode assembly) to generate electricity and carbon dioxide bubbles 712. The carbon dioxide 711 flows from the fuel electrode 706 into the flow path 635 for the carbon dioxide 711 through the pores of the porous thin film 704 as indicated by an arrow 703 and is discharged. A portion 720 of the porous thin film 704 is made of resin or the like so that liquid or gas cannot pass therethrough. In order to operate an ultra-compact fuel cell efficiently, it is preferable to extend a fine flow path as shown in FIG. 15A.

  In the present specification, a material having high wettability with respect to a liquid is referred to as hydrophilic, and a material having low wettability is referred to as hydrophobic. For example, in the above-described embodiment, ethanol is used as the fuel of the fuel cell, and the wettability with respect to ethanol is expressed as hydrophilic / hydrophobic. Therefore, when so-called petroleum is used as the fuel, the hydrophilicity is read as lipophilic in the petroleum flow path.

<< Sixth Embodiment: Fuel Cell System >>
FIG. 18 is a schematic cross-sectional view showing an embodiment of a fuel cell system using the fuel cell according to the present invention. This embodiment will be described with reference to FIG. In the following description, the configuration and operation of the fuel cell are the same as those in the third embodiment described above, and therefore the description will not be repeated.

  The fuel cell system according to this embodiment includes a fuel cell 500 according to the third embodiment, an oxygen supply unit 912, a fuel supply unit 909, a fuel tank 903, an air tank 901, and a manual pump 902. The oxygen supply unit 912 is connected to the oxygen supply port of the fuel cell 500 and the air tank 901. In the present invention, the “air tank” is a gas containing oxygen. The concentration of oxygen in the gas is not particularly limited, but is preferably 18% or more. The “air tank” is filled with oxygen. It may be an “oxygen tank”. In this embodiment, the oxygen supply part 912 is a cylindrical connection part, but the shape is not particularly limited as long as it is connected to both the oxygen supply port and the air tank 901. The fuel supply unit 909 is connected to the fuel supply port of the fuel cell 500 and the fuel tank 903. In the present embodiment, the fuel supply unit 909 is a cylindrical connecting unit like the oxygen supply unit 912, but the shape is not particularly limited.

  The air tank 901 is connected to a manual pump 902 separately from the oxygen supply unit 912. The shape of the manual pump 902 is not particularly limited as long as, for example, oxygen (air) can be manually introduced into the oxygen supply unit. As described later, by installing a regulator in the air tank 901 or the oxygen supply unit 912, the inside of the air tank 901 can be set to a high pressure. As a result, high-density air can be sent into the fuel cell 500, so that power can be generated efficiently. According to the fuel cell system of this embodiment, it is possible to operate stably even in a place where atmospheric pressure is low, such as a mountainous area and a highland.

  The air tank 901 and the fuel tank 903 are connected directly or indirectly. For example, oxygen in the air consumed in the fuel cell 500 becomes water vapor, and unused air and the water vapor are partly sent to the fuel tank 903. In this manner, the fuel in the fuel tank 903 can be pumped to the fuel cell 500 by directly or indirectly utilizing the pressure in the air tank 901. Therefore, fuel can be supplied efficiently and stably, and a high-power fuel cell can be realized stably.

  Here, the state in which the air tank 901 and the fuel tank 903 are directly connected refers to a state in which the air tank 901 and the fuel tank 903 are directly connected by the connecting portion 905 or the like. Specifically, in the case of being directly connected, it means a state in which the pressure of the air tank 901 is used to transmit liquid fuel to the fuel cell 500. The state in which the air tank 901 and the fuel tank 903 are indirectly connected refers to a state in which the air tank 901 and the fuel tank 903 are indirectly connected. Specifically, in the indirectly connected state, the oxygen supply unit 912 and the fuel tank 903 are connected via a fuel cell as an oxygen supply source of the fuel cell.

  In the present embodiment, the positions of the connecting portion 905, the fuel supply portion 909, the fuel tank 903, and the like are set in consideration of the relationship between the direction in which the fuel cell system is installed and gravity. For example, when the fuel cell system is arranged so that gravity is applied downward in FIG. 18, liquid fuel can be supplied to the fuel cell 500 from below and carbon dioxide can be discharged from above. . The water vapor can be set to be discharged downward so as not to be clogged when liquefied.

<< Seventh Embodiment: Fuel Cell System >>
FIG. 19 is a schematic cross-sectional view showing an embodiment of a fuel cell system using the fuel cell according to the present invention. This embodiment will be described with reference to FIG.

  The fuel cell system according to the present embodiment is designed to further include a pressure regulating valve and a regulator with respect to the fuel cell system according to the sixth embodiment.

  In the present embodiment, the pressure regulating valves 906 and 908 are connected to the connecting portion 905 that directly or indirectly connects the air tank 901 and the fuel tank 903 and / or the gas discharge portion 907 that is connected to the fuel tank 903. is set up. The pressure regulating valve 906 installed in the connecting portion 905 has a check valve structure. Thereby, it is possible to prevent the fuel from flowing backward from the fuel tank 903. A pressure adjustment valve 908 installed in the gas discharge unit 907 is a valve for keeping the pressure in the fuel tank 903 constant. These pressure regulating valves prevent excessive fuel from being supplied due to excessive pressure.

  The regulator 904 installed in the air supply unit 912 can send out air at a constant pressure from the air tank 901. The fuel supply unit 909 is preferably provided with a regulator 910. This is because the fuel can be supplied to the fuel cell 500 constantly.

  In the present embodiment, the position of each component is set in consideration of the relationship between the direction in which the fuel cell system is installed and gravity. For example, in the present embodiment, when the fuel cell system is arranged so that gravity is applied downward in FIG. 19, the liquid fuel can be supplied from the bottom to the top.

<< Eighth Embodiment: Fuel Cell System >>
FIG. 20 is a schematic cross-sectional view showing one embodiment of a fuel cell system using the fuel cell according to the present invention. This embodiment will be described with reference to FIG.

  In the fuel cell system of this embodiment, the arrangement and orientation of each component are devised with respect to the fuel cell system of the seventh embodiment. In the case where the fuel cell system is placed on the ground and operated so that gravity is applied downward in FIG. 20, the electrolyte membrane 503 in the fuel cell is disposed substantially perpendicular to the ground. That is, the fuel tank is provided at a position where fuel can be supplied substantially parallel to the in-plane direction of the electrolyte membrane 503 of the fuel cell. Further, the fuel tank is disposed so as to be located closer to the ground (lower side) than the fuel cell. By adopting such a configuration, before the water vapor is discharged to the outside of the fuel cell system, the water vapor (water) smoothly liquefied by gravity even if liquefied in the middle can be discharged to the outside of the fuel cell system. it can. Further, even when the fuel oozes out to the carbon dioxide side discharge side, the fuel can be prevented from leaking out of the fuel cell system.

  In the fuel cell system of the present embodiment, the liquid fuel can be efficiently and stably supplied, so that a high output can be stably realized.

  The fuel cell system in each of the above-described embodiments of the present invention can be used as a portable generator that is small and convenient to carry.

  In the present invention, for example, the oxygen supply unit and the fuel described in the sixth embodiment, the seventh embodiment, and the eighth embodiment as appropriate for the fuel cells of the third embodiment, the fourth embodiment, and the fifth embodiment. A supply part, a fuel tank, an air tank, a manual pump, etc. can be combined.

  In addition, the fuel cells in the sixth embodiment, the seventh embodiment, and the eighth embodiment have small dimensions that are difficult to see, and the air tank and the fuel tank may be selected to be larger than the size of a small simple lighter. Is possible. It is also possible to produce a fuel cell system in which a plurality of fuel cells are electrically connected in series or in parallel.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated in detail, this invention is not limited to these.

  FIG. 17 shows the hydrophilicity and durability of a conventional high molecular weight polymer (Δ in the figure) subjected to only ozone treatment and a high molecular weight polymer (● in the figure) having a channel formed on the surface according to the present invention. The graph which shows is shown. The horizontal axis indicates the standing time in a dry environment, and the vertical axis indicates the contact angle of pure water droplets.

In the polymer according to the present invention, carbon negative ions were ion-implanted at an energy of 10 keV by 3 × 10 ¹⁵ ions / cm ² . The high molecular polymer and a high molecular polymer not subjected to ion implantation were subjected to ozone treatment in the atmosphere under the condition of about 0.5 mW / cm ² of UV irradiation for 20 minutes.

  As shown in FIG. 17, it was confirmed that the polymer according to the present invention has improved hydrophilicity and durability. In addition, the contact angle measurement method was used for hydrophilicity evaluation of FIG. A water droplet having a diameter of 1 nm or less or about 1 μL was gently placed on the sample, and photographed with a microscope from the side. On the image, the contact angle was formed from the lateral width and height by approximating the droplet with an arc.

  It should be understood that the embodiments and examples disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is sectional drawing of one Embodiment of the member in this invention. A is a cross-sectional view taken along line IIA-IIA in FIG. 1, and B is a cross-sectional view of one embodiment showing another aspect of the member in the present invention. It is sectional drawing of one Embodiment showing another aspect of the member in this invention. It is a typical top view of a part of biochip using the member concerning the present invention. It is a figure which shows the cross section along the VV line in FIG. 4, and a lid | cover. It is a top view of the part of the biochip according to another situation of this embodiment. It is sectional drawing of the part of the biochip according to another situation of this embodiment. It is sectional drawing of the part of the biochip according to another situation of this embodiment. A is a schematic cross-sectional view of a part of a fuel cell using a member according to the present invention, and B is a schematic plan view of a wall surface constituting a flow path in the fuel cell shown in A. FIG. FIGS. 9A and 9B are schematic cross-sectional views of a part of a flow path in the fuel cell shown in FIG. 9A. It is typical sectional drawing of a part of fuel cell according to another situation of this embodiment. A is a schematic cross-sectional view of a part of a fuel cell using a member according to the present invention, and B is a schematic plan view of a wall surface constituting a flow path in the fuel cell shown in A. FIG. FIGS. 12A and 12B are schematic cross-sectional views of a part of a flow path in the fuel cell shown in FIG. 12A. It is typical sectional drawing of a part of fuel cell according to another situation of this embodiment. A is a schematic perspective view of a fuel cell using a member according to the present invention, and B is a diagram schematically showing a part of a cross section taken along line XVB-XVB in A. FIG. A and B are diagrams schematically showing the operation of the fuel cell according to the present embodiment. A graph showing the hydrophilicity and durability of a conventional high molecular weight polymer (Δ in the figure) subjected to only ozone treatment and a high molecular polymer (● in the figure) having a channel formed on the surface according to the present invention. Indicates. It is typical sectional drawing which shows one form of the fuel cell system using the fuel cell which concerns on this invention. It is typical sectional drawing which shows one form of the fuel cell system using the fuel cell which concerns on this invention. It is typical sectional drawing which shows one form of the fuel cell system using the fuel cell which concerns on this invention.

Explanation of symbols

  101, 201, 701 Substrate, 102, 103, 105, 202 Chamber, 104, 106, 206, 501, 505, 635 Flow path, 107 Lid, 108, 109 hole, 110, 210 member, 205 Hydrophilized region, 207 Lid , 208 Hydrophobic region, 500 Fuel cell, 502,707 Oxidant electrode, 503,705 Electrolyte membrane, 504, 706 Fuel electrode, 511, 515, 521, 525, 631 Wall surface, 702, 703 arrow, 704 Porous thin film, 708 Supply port, 709 discharge port, 710 liquid fuel, 711 carbon dioxide, 712 bubble, 720 part, 901 air tank, 902 manual pump, 903 fuel tank, 904 regulator, 905 connection, 906, 908 pressure regulating valve, 907 gas discharge Part, 909 Fuel supply part, 910 Regi Regulator, 912 an oxygen supply unit.

Claims (12)

A member made of a polymer having a flow path formed on the surface,
A member having a hydrophilized region in which at least a part of the surface of the wall surface constituting the flow path is hydrophilized by implanting carbon ions by ion implantation.   The member according to claim 1, wherein at least a part of a surface of the wall surface constituting the flow path further has a hydrophobic region. The ion implantation member of claim 1 or 2 is implanted negative ions. Implantation energy in the ion implantation member according to any one of claims 1 to 3, at least 1 keV 100 keV or less. The ion dose in the ion implantation ^{is, 1 × 10 14 ions / cm} 2 or more 1 × 10 ¹⁷ ions / cm ² or less members according to any one of claims 1 to 4. The member in any one of Claims 1-5 exposed to oxidizing atmosphere after the said ion implantation. Member according to any one of claims 1 to 6 as a plasma treatment or ozone treatment after the ion implantation. Biochip utilizing the member according to any one of claims 1-7. The fuel cell using a member of any of claims 1-7. A fuel cell system using the fuel cell according to claim 9 ,
The fuel cell, an oxygen supply unit, a fuel supply unit, a fuel tank, an air tank, and a manual pump;
The oxygen supply unit is connected to an oxygen supply port in the fuel cell and the air tank,
The fuel supply unit is connected to a fuel supply port in the fuel cell and the fuel tank,
The air tank is further connected to the manual pump,
The fuel tank system in which the air tank and the fuel tank are connected directly or indirectly. A pressure adjusting valve for adjusting the pressure in the fuel tank is provided in a connecting portion that directly or indirectly connects the air tank and the fuel tank and / or a gas discharge portion that is connected to the fuel tank. Further comprising
The fuel cell system according to claim 10 , wherein a regulator is further installed in the air supply unit. The fuel cell system according to claim 10 or 11 , wherein the fuel tank is provided at a position where fuel can be supplied substantially parallel to an in-plane direction of an electrolyte membrane of the fuel cell.

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