JP4872879B2 - Surface coated member, method for producing the same, and heat exchanger - Google Patents

Description

  The present invention relates to a member with a surface coating mainly used for a heat exchanger, an evaporator, a heater, an oil cooler, a radiator, a condenser, etc., a manufacturing method thereof, and a heat exchanger. Surface coated member with ability to generate active oxygen in contact with water and its durability, such as fins, plates, etc., and members for heat exchangers, its manufacturing method, car air conditioner, air conditioner, etc. In addition to having a tube with heat exchanger members such as fins and plates, and having durability such as water resistance and chemical resistance, heat exchange members such as fins and plates, and the surface of the tube The present invention relates to a novel heat exchanger that has a function of deodorizing and deodorizing odorous substances adhering to the odorant and a function of sterilizing harmful microorganisms. In particular, the heat exchanger of the present invention can efficiently generate hydrogen peroxide and active oxygen for deodorization or sterilization by using polyaniline on the surface of a heat exchange member such as a tube, fin, or plate.

  Hydrogen peroxide has been known to generate active oxygen such as OH by itself, or by bringing hydrogen peroxide into contact with iron ions, etc., and has a certain effect along with chlorine, ozone, ultraviolet light, photocatalyst, etc. Since it can be expected, it is used for sterilization and disinfection in various fields.

  So far, a method of contacting polyaniline or the like is known as a method for generating hydrogen peroxide. For example, Patent Document 1 describes an active oxygen generator containing polyaniline capable of generating active oxygen useful for sterilizing microorganisms or the like that live in water, and an active oxygen generating method using the active oxygen generator. Yes. Further, Patent Document 2 is for sterilizing drinking water, cooling water, or other service water, in which a cathode and a cathode with polyaniline in contact with the surface are disposed between the electrodes. A method of using superoxide generated by energization for sterilization and a water treatment apparatus used for this sterilization method are described. Further, Patent Document 3 is for generating active oxygen in water, and the surface of the conductive material is coated with a conductive composition composed of powder of the conductive material and / or fiber, binder and polyaniline. And the superoxide anion radical is generated by energizing the coating as a cathode.

  Furthermore, Patent Document 4 describes an active oxygen generator. This active oxygen generator includes an anode and a redox polymer capable of generating active oxygen, for example, a cathode carrying polyaniline or a derivative thereof, and has a thickness of 0. A spacer in the range of 005 to 5 mm is interposed. Patent Document 5 describes an active oxygen generator characterized by having an electrode and a redox polymer having active oxygen generating ability, such as particles carrying polyaniline or a derivative thereof on the surface.

  In addition, Patent Document 6 describes a method for producing a corrosion-protected metal material and a material obtained by this method. More specifically, US Pat. No. 6,057,059 describes (a) a metal material, such as a phosphated metal material or an already corroded metal, by a non-electrochemical method using (a) an intrinsically conductive and water-absorbing polymer, preferably polyaniline. Forming on a material, such as steel, stainless steel, copper, aluminum, bronze or other alloy; (b) contacting the metal material coated by the above step with a passivating medium containing oxygen-containing water for at least 30 seconds; (C) If necessary, secondary passivation treatment is performed, and (d), if necessary, the conductive polymer layer is removed. (E) If necessary, the corrosion protection film is made of metal. It is in the manufacturing method of the metal material characterized by applying to material. The ultimate object of the present invention is protection from corrosion due to the formation of a passive film on the surface of the metal material, and the water-absorbing polymer formed in step (a), preferably polyaniline, is formed in step (d). It is also possible to remove in

  However, since the purpose of Patent Document 6 is to “passivate” the lower layer metal, it can be easily removed as seen in the step (d) after “passivation” and Example 6. A heat exchanger that is considered to be a more convenient polyaniline film and requires water resistance and chemical resistance over a long period of several years to 10 years or more, especially a film that forms the outermost surface of a member constituting the evaporator As such, only unsuitable ones are disclosed.

  Further, this document does not describe a countermeasure against the fact that when polyaniline generates active oxygen, it takes electrons from a base metal and causes rust. In a heat exchanger in which a refrigerant or the like circulates, it is not preferable to make a hole in the tube portion because the product function is lost.

Japanese Patent Laid-Open No. 9-175801 Japanese Patent Laid-Open No. 10-99863 Japanese Patent Laid-Open No. 10-316403 JP-A-11-79708 Japanese Patent Laid-Open No. 11-158675 JP-T 8-500770

  An object of the present invention is to provide a member with a surface coating having active oxygen generation ability and durability in contact with water, such as fins and plates for heat exchangers such as car air conditioners and air conditioners, and car air conditioners, In a heat exchanger with tubes and fins, such as an air conditioner, it not only has a function of deodorizing and deodorizing odorous substances adhering to the surfaces of the tubes and fins, and a function of sterilizing harmful microorganisms, but also lowering its decomposition and deodorizing function and sterilizing function. It is an object of the present invention to provide a novel member with a surface coating and a heat exchanger that can maintain the basic performance as they are, and have both excellent active oxygen generation ability and durability.

  The present inventors paid attention to the fact that polyaniline as described above can generate hydrogen peroxide when it comes into contact with moisture or other moisture, and further, polyaniline that generates hydrogen peroxide. As a result of repeated studies to develop a method and an apparatus using the method for efficiently maintaining long-term capability, the peak intensity located at one specific Raman shift in the Raman spectrum and the other Raman shift are located. Obtained the knowledge that a polyaniline film having a good active oxygen generation capacity and a structure that is difficult to peel off can be obtained at a polyaniline molecular structure ratio in which the ratio of the peak intensity to be in a specific range, and the present invention was completed based on that knowledge It came to do.

  That is, the present invention is to select a polyaniline structure that easily generates active oxygen, and to achieve a polyaniline coating with enhanced active oxygen generation capability and long-term durability. Polyaniline is generally considered to have a high ability to generate active oxygen when a benzenoid structure and a quinoid structure are present in the polyaniline molecule at a ratio of approximately 1: 1. However, the ability to generate active oxygen and its durability include the structural ratio of the polyaniline molecular structure expressed by the ratio of the peak intensity located at one specific Raman shift to the peak intensity located at the other Raman shift in the Raman spectrum. It was found to work. Therefore, in order to generate active oxygen permanently, it is necessary to control the ratio of the peak intensity located at one specific Raman shift and the peak intensity located at another Raman shift in the Raman spectrum. If this peak intensity ratio is in a specific range, sufficient active oxygen generation ability and durability can be exhibited. Therefore, the present invention is characterized by controlling the structure of polyaniline based on a specific peak intensity ratio in a Raman spectrum at the time of film formation or discovery of deterioration in order to generate active oxygen from polyaniline permanently. A surface-coated member and a heat exchanger having a generating function and durability thereof are provided.

In short, the present invention provides, as one aspect, a member with a surface coating comprising at least a substrate and a surface coating formed on at least a part of the outermost surface of the substrate.
The surface coating is a surface polyaniline layer composed of polyaniline and / or a derivative thereof capable of generating active oxygen or hydrogen peroxide by reacting with moisture in a fluid brought into contact therewith, and the polyaniline and / or the polyaniline represented I ₂ / I ₁ ratio of the peak intensity I ₂ is located in the peak intensity I ₁ and the Raman shift 1415cm ^-1 ± 30cm ^-1 located Raman shift 1215 cm ^-1 ± 30 cm ^-1 in the Raman spectrum of the derivative The molecular structure ratio is in the range of 0.75 to 1.0,
A member with a surface coating is provided.

  According to the member with a surface coating of the present invention having such a configuration, it is a component used in a heat exchanger, an evaporator, etc., and has an excellent effect of having an excellent active oxygen generation function and its durability. Is.

Further, the present invention, as another aspect, generates active oxygen or hydrogen peroxide by reacting with water in a fluid which is formed on at least a part of the outermost surface of the substrate and brought into contact with the fluid. possible polyaniline and (or) Ri surface polyaniline layer der consists derivatives thereof, and wherein the polyaniline and (or) the peak intensity I ₁ Raman shift which is located Raman shift 1215 cm ^-1 ± 30 cm ^-1 in the Raman spectrum of the derivative With a surface coating comprising a polyaniline molecular structure ratio represented by a ratio I ₂ / I ₁ of peak intensity I ₂ located at 1415 cm ⁻¹ ± 30 cm ⁻¹ in a range of 0.75 to 1.0 A method for manufacturing a member, comprising:
Applying a solution containing less than 2% by weight of the polyaniline and / or its derivative to the surface of the substrate;
A primary drying step of drying the substrate to which the solution is applied at 60 to 80 ° C . ;
A secondary drying step of further drying the primary dried substrate at 130 to 150 ° C., and
After the secondary drying process, the polyaniline and (or) peak located at the peak intensity I ₁ and the Raman shift 1415cm ^-1 ± 30cm ^-1 located Raman shift 1215 cm ^-1 ± 30 cm ^-1 in the Raman spectrum of the derivative Measuring intensity I ₂ ;
A method for producing a member with a surface coating is provided.

  According to the method for producing a member with a surface coating of the present invention having such a configuration, the member with a surface coating such as an evaporator or a heat exchanger having an excellent active oxygen generation function and durability can be obtained. Is.

In another aspect of the present invention, a heat exchanger having a finned tube is provided.
The tube and / or fin comprises at least a substrate and a surface coating formed on at least a part of the outermost surface of the substrate,
The surface coating is a surface polyaniline layer composed of polyaniline and / or a derivative thereof capable of generating active oxygen or hydrogen peroxide by reacting with moisture in a fluid brought into contact therewith, and the polyaniline and / or the polyaniline represented by the ratio I ₂ / I ₁ of the peak intensity I ₂ is located in the Raman shift 1215 cm ^-1 peak intensity located ± 30 cm ^-1 I ₁ Raman shift 1415cm ^-1 ± 30cm ^-1 in the Raman spectrum of the derivative The molecular structure ratio is in the range of 0.75 to 1.0,
A heat exchanger is provided.

  According to the heat exchanger of the present invention having such a configuration, it has an excellent effect that it can surely have an excellent active oxygen generation function and its durability.

  In the member with a surface coating and the heat exchanger according to the present invention, as a result of adopting the above-described configuration, the odor component or bacteria is generated from polyaniline and / or a derivative thereof firmly formed on the member or the heat exchanger. It is decomposed or sterilized at normal temperature by the oxidation of active oxygen, thus preventing odorous components or bacteria from becoming a source of odor generation or bacteria growth for a long time without impairing the water-wetting performance of the heat exchanger. Can do.

In fact, according to the present invention, as will be understood from the following detailed description, excellent durability, for example, in a heat exchanger including a tube provided with heat exchange members such as fins and plates, for example, Not only can water resistance and chemical resistance be obtained, but also by maintaining the peak intensity ratio I ₂ / I ₁ in the Raman spectrum of the surface polyaniline layer within a predetermined range, the polyaniline after film formation and after use Adhering odor can be suppressed and the basic performance of the heat exchanger can be maintained without reducing the active oxygen generation capacity. Therefore, the present invention can be advantageously used particularly in car air conditioners, air conditioners, radiators, and other heat exchangers mounted on vehicles.

According to the present invention, the peak intensity ratio I ₂ / I ₁ can be obtained from the measurement result of the Raman spectrum of the surface polyaniline layer, the benzenoid structure and the quinoid structure can be easily evaluated, and ₁₀₀ % inspection is possible. In addition, there is a method for measuring the benzenoid / quinoid ratio in the surface polyaniline layer by UV-VIS absorbance spectrum, but this method requires that the substrate and the polyaniline layer be transparent, otherwise the polyaniline layer is used as a solvent. There is a problem that it is necessary to dissolve, and when polyaniline cross-linking proceeds, it cannot be dissolved in a solvent, and the total number cannot be inspected.

  The surface-coated member used in the heat exchanger, evaporator, heater, oil cooler, radiator, condenser, etc. of the present invention can be implemented in various forms usually used in those applications. Further, the heat exchanger of the present invention is a oxygen peroxide generation type heat exchanger, and can be advantageously implemented in various forms. In addition, the heat exchanger of this invention is not necessarily limited to the form described below.

  The heat exchanger of the present invention will be described in detail below, but the member with a surface coating of the present invention can be similarly applied as a representative example of a member for a heat exchanger. The heat exchanger of the present invention includes a tube with heat exchange members (hereinafter collectively referred to as “fins”) such as fins (blades) and plates, and can include various forms. . That is, the heat exchange member used for the purpose of improving the heat exchange efficiency in such a heat exchanger includes various forms such as fins and plates, and is preferably composed of a member having a large surface area. As will be described below in terms of the substrate, it is preferably formed from a lightweight metal material. Of course, the size of the fin can be arbitrarily changed according to the desired effect.

  The tube to which the fin is attached can also include various forms. For example, the tube may have a circular cross section, a rectangular cross section, or a flat cross section such as a crushed circle. When considering miniaturization and weight reduction of the heat exchanger, a tube having a flat cross section is useful. The tube is preferably formed from a lightweight metal material, similar to the fins. Of course, the size of the tube can be arbitrarily changed according to the desired effect, etc., as with the fin.

  The finned tube can be arranged in various ways in the heat exchanger, and its arrangement and structure are not particularly limited. For example, a heat exchanger having a predetermined shape may be configured by bending a long finned tube a plurality of times, otherwise, a tube member composed of a plurality of tubes, and the tube member A heat exchanger may be configured by preparing a fin member having a suitable shape and joining the tube member and the fin member.

  A typical example of the heat exchanger is an air conditioner for an automobile, that is, an evaporator or a condenser (condenser) used in a car air conditioner. Applications other than car air conditioners are not limited to those listed below, but include air conditioners, radiators, heaters, oil coolers, condensers, and the like.

  FIG. 1 schematically shows the use of a heat exchanger (use as an evaporator) in a car air conditioner. Slightly warm air (see warm air indicated by arrow A) is sent from the blower 21 to the car air conditioner 22. The hot air further passes through the filter 23 and then reaches the heat exchanger 10 to perform scheduled heat exchange. Air (cold air) cooled by heat exchange is discharged in a direction indicated by an arrow B from a duct 24 attached to the car air conditioner 22.

  The heat exchanger 10 can have various forms as described above. FIG. 2 is a cross-sectional view schematically showing a part of the heat exchanger 10. The heat exchanger 10 is obtained by joining the tube member 15 and the fin member 17, and the surface polyaniline layer 2 is provided on all the outermost surfaces of both the joined members. If necessary, a part of the surface polyaniline layer 2 can be omitted. In the tube member 15, the substrate 1 is made of an aluminum alloy, and the exposed portion is covered with the surface polyaniline layer 2. A refrigerant 16 is caused to flow inside the tube member 15. The refrigerant 16 is, for example, a fluorine-containing hydrocarbon such as 1,1,1,2-tetrafluoroethane (hydrofluorocarbon (HFC) refrigerant such as HFC134a). Here, heat exchange is performed on one surface of the tube member 15. In order to increase efficiency, a fin member 17 having an uneven cross-sectional pattern is attached by brazing (not shown) The fin member 17 has a base 1 made of an aluminum alloy, like the tube member 15. The exposed portion is covered with the surface polyaniline layer 2. In the figure, the fin member 17 having a concave and convex cross-sectional pattern is shown, but instead of the concave and convex cross sectional pattern, a triangular shape like a bellows is shown. You may use the fin member 17 by which the cross-sectional pattern was repeated, and the fin member 17 of another cross-sectional pattern.

  More specifically, FIG. 3 is a cross-sectional view further enlarging the fin portion of the heat exchanger shown in FIG. As shown in the figure, in the heat exchanger of the present invention, the fin 17 is composed of a base 1 and a surface polyaniline layer 2 formed on the outermost surface thereof. In the figure, for simplicity, other layer films are not shown, but an interlayer intermediate layer is provided between the base material 15 and the surface polyaniline layer 2 as illustrated and described below. Or other layer films may be provided. Further, the base 1 and the surface polyaniline layer 2 may be subjected to an arbitrary treatment in order to improve the bonding between them. Further, the surface polyaniline layer 2 may additionally undergo any treatment on the surface.

  In the fin and the tube provided with the fin, the substrate can be formed of various materials. However, in the practice of the present invention, a metal material, a special lightweight metal material, especially a metal material containing aluminum (aluminum alloy) Or an aluminum mixture) can be used advantageously. This is because the aluminum-containing metal material is lightweight, has good heat exchange efficiency, and is excellent in durability and corrosion resistance. Typical aluminum-containing metals are Al-Mn alloys, Al-Si alloys, Al-Mg alloys, Al-Mg-Si alloys, Al-Cu alloys, Al-Zn alloys, Al-Zn-Mg alloys, etc. . Examples of useful base materials other than aluminum-containing metals include copper and resin materials.

  In the practice of the present invention, the fin and the tube provided with the fin can each be advantageously formed by molding from an aluminum-containing metal material or other metal material which is a base material. Examples of suitable molding methods include extrusion molding and pressing. If necessary, these members may be produced by, for example, forging or cutting instead of forming.

  The fin and the tube may be manufactured separately, and may be integrated in a later step, or may be manufactured integrally or substantially simultaneously with the fin and the tube. Generally, it is preferable that the fin and the tube are formed from the same metal material. In the case where the fin and the tube are integrated in the subsequent process as in the former case, any joining means can be used. Examples of suitable joining means include brazing, welding, adhesion, and compression. When brazing is used, after the joining is completed, the brazing agent after use is washed away with acid or alkali.

  The surface polyaniline layer may be provided entirely on the outermost surface of the substrate constituting the fins and tubes, or may be provided partially on the outermost surface of such a substrate. Of course, if necessary, it may be provided entirely only on the outermost surface of the fin or tube, or may be selectively provided only on a portion of the outermost surface of the fin or tube. FIG. 2 illustrates one mode in which the surface polyaniline layer 2 is provided on the entire exposed outermost surfaces of the tube member 15 and the fin member 17 of the heat exchanger 10 (the outermost surface of the substrate 1).

  The surface polyaniline layer is preferably formed entirely on the outermost surface of the substrate 1, but if desired, it may be selectively formed only at necessary portions. The surface polyaniline layer can be formed from polyaniline having a benzenoid structure and a quinoid structure and / or a derivative thereof, as represented by the following general formula. In the following, these compounds, which are also simply referred to as “polyaniline compounds”, can generate hydrogen peroxide and thus active oxygen by reacting with the moisture of fluids such as outside air brought into contact therewith. Here, “moisture” includes fluid such as outside air, that is, moisture, water and other moisture contained in the external atmosphere.

  Here, the polyaniline compound represented by the above formula is commercially available from Aldrich under the trade name “Polyaniline, emeraldine base”, for example. Further, the derivatives of polyaniline are not limited to those described below, but examples thereof include sulfonated polyaniline.

In the heat exchanger of the present invention, the polyaniline on the surface polyaniline layer and (or) the peak intensity I ₁ and the Raman shift 1415cm ^-1 ± 30cm ^-1 located Raman shift 1215 cm ^-1 ± 30 cm ^-1 in the Raman spectrum of the derivative The polyaniline molecular structure ratio represented by the ratio I ₂ / I ₁ of the peak intensity I ₂ located at is important. Usually, the peak intensity ratio I ₂ / I ₁ is preferably in the range of 0.75 to 1.0, and more preferably in the range of 0.8 to 1.0. The Raman spectrum can be measured using, for example, a Raman spectrum measuring instrument NSR-3000 (trade name) manufactured by JASCO Corporation, LabRam HR-800 sold by HORIBA, Ltd.

4 shows, in the heat exchanger of the present invention, three in the Raman spectra of polyaniline on the surface polyaniline layer (S1 to S3), the peak intensity I ₁ and the Raman located Raman shift 1215 cm ^-1 ± 30 cm ^-1 A typical relationship of peak intensity I ₂ located at shift 1415 cm ⁻¹ ± 30 cm ⁻¹ is shown. Here, for example, in the case of S1, regarding the peak intensity ratio I ₂ / I ₁ , I ₁ is 886 (excluding the base), I ₂ is 1136 (excluding the base), and the peak intensity ratio I ₂ / I ₁ Is 1.28. Similarly, in the case of S2, the peak intensity ratio I ₂ / I ₁ is 0.88 (660/750), and in the case of S3, the peak intensity ratio I ₂ / I ₁ is 0.87 (795/910). In FIG. 4, a straight line connecting the left end and the right end of each curve is a line indicating the base.

Incidentally, as shown in FIG. 4, towards the surface polyaniline layer of the peak intensity ratio I ₂ / I ₁ lower S3 is active oxygen generating ability than the surface polyaniline layer of the peak intensity ratio I ₂ / I ₁ high S1 S1 surface polyaniline layer having a high peak intensity ratio I ₂ / I ₁ is higher than the S3 surface polyaniline layer having a lower peak intensity ratio I ₂ / I _1. Many are difficult to peel off. As shown in FIG. 9 to be described later, when the peak intensity ratio I ₂ / I ₁ is larger than 1.0, the active oxygen generation concentration rapidly decreases, but the peeling does not change so much. In that sense, it can be said that S1 shown in FIG. 4 is located outside the scope of the present invention. Moreover, when the peak intensity ratio I ₂ / I ₁ is in the range of 0.8 to 1.0, the active oxygen generation ability and the resistance to peeling are particularly easily compatible and preferable.

  The surface polyaniline layer can be formed in various thicknesses, but is usually about 0.1 to about 10 μm, preferably about 0.1 to about 1 μm, and more preferably about 0.00. 1 to about 0.5 μm. If the thickness of the surface polyaniline layer is less than 0.1 μm, the desired effect cannot be expected. On the other hand, if the thickness exceeds 10 μm, film formation becomes difficult.

  In the method for producing a member with a surface coating according to the present invention, various film forming methods can be used for forming a surface polyaniline layer. Specifically, less than 2% by weight of polyaniline and / or An application step of applying a solution containing the derivative to the surface of the substrate, a primary drying step of drying the substrate to which the solution has been applied at 60 to 80 ° C., and the primary dried substrate further at 130 to 150 ° C. It includes a secondary drying step of drying.

If the concentration of polyaniline and / or its derivative in the solution is 2% by weight or more, gelation occurs during storage of the solution, which is not preferable. Further, the binder is preferably mixed and used up before application. For example, the composition of a polyaniline-containing solution suitable for forming the surface polyaniline layer is as follows.
Polyaniline about 0.1 to about 2% by weight Binder (carbodiimide compound) about 0 to about 20% by weight Solvent (water or organic solvent) about 80 to about 99.9% by weight

  Of course, the above composition can be arbitrarily changed. For example, a polymer having a sulfate group or a phosphate group, a silane coupling agent, or the like can be advantageously used as a binder. Further, as a solvent, for example, alcohols such as methanol and ethanol may be used in substantially the same amount instead of water.

  Various film forming methods can be used for forming the surface polyaniline layer. Generally, a dipping method in which a precursor of a heat exchanger is immersed in a polyaniline-containing solution or a polyaniline-containing solution is applied. The application method is advantageous. For example, the dipping process can be advantageously carried out by dipping the heat exchanger precursor in a polyaniline-containing solution as described above at a temperature of about 4 to about 30 ° C. for about 1 minute.

  The primary drying step of drying the substrate to which the solution has been applied is at 60-80 ° C, more preferably at 60-70 ° C, and for about 10 to about 25 minutes, preferably about 10 to about 20 minutes, more preferably. For about 10 to about 15 minutes, even more preferably for about 10 to about 11 minutes. When the temperature is less than 60 ° C., a drying time of 10 minutes or more is required. When the temperature exceeds 80 ° C., spots and bubbles are not preferable because the film after drying is unfavorable. If an air drying step is performed for drying, the drying temperature can be lowered by 10 to 20 ° C. In addition, the drying time can be shortened by introducing an air drying step, specifically about 10 minutes or less, preferably about 5 to about 10 minutes. The secondary drying step of further drying the primary dried substrate is at 130 to 150 ° C, more preferably at 130 to 140 ° C, and for about 5 to about 20 minutes, preferably about 10 to about 20 minutes. More preferably from about 10 to about 15 minutes, even more preferably from about 10 to about 11 minutes. If the temperature is less than 130 ° C., the strength of the film may be lowered, and if it exceeds 150 ° C., crosslinking proceeds and affects the ability to generate active oxygen. Further, if the above drying time is required, the crosslinking may proceed even at a temperature lower than 130 ° C., so care must be taken in managing the drying time.

In the manufacturing method of the surface coating with members of the present invention, secondary drying after step, polyaniline and (or) the peak intensity I ₁ and the Raman located Raman shift 1215 cm ^-1 ± 30 cm ^-1 in the Raman spectrum of the derivative It is desirable to further include the step of measuring the peak intensity I ₂ located at the shift of 1415 cm ⁻¹ ± 30 cm ⁻¹ . The measurement is preferably performed using the Raman spectrum as described above, for example, under the conditions of an exposure time of 30 seconds, an integration count of 2 times, an excitation wavelength of 532 nm, a grating of 1800 L / mm, and a laser intensity of 0.8 mW.

  In the heat exchanger of the present invention, the surface polyaniline layer constituting the uppermost layer can be variously improved. For example, in the fin 17 for heat exchangers shown in FIG. 5, the surface polyaniline layer 2 formed on the substrate 1 may further have a hydrophilic functional group FG on the surface portion. The hydrophilic functional group FG may be various functional groups having hydrophilicity, but preferably a first amino group, a second amino group, a third amino group, an ammonium group, a nitric acid group, a carboxyl group, a sulfone. It is selected from acid groups, hydroxyl groups and the like. One kind of these functional groups may be given alone, or two or more kinds may be given in combination. The presence of the hydrophilic functional group FG is particularly useful for improving the water leakage of the heat exchanger.

  By the way, the hydrophilic functional group as described above can be applied from a binder in combination with the polyaniline compound when the surface polyaniline layer is formed from the polyaniline compound, more preferably the hydrophilic functional group. The group can be added to the binder in advance. Suitable binders are not limited to those listed below, but include, for example, carbodiimide groups and carboxyl groups. For example, the hydrophilic functional group can be easily added to the amino group portion of the polyaniline-based compound by the action of the binder and distributed almost uniformly on the surface portion of the surface polyaniline layer to be formed.

  The fins and tubes are usually formed from the substrate referred to in the present invention. The base of these members is preferably formed by any metal material, preferably a lightweight metal formulation, as described above. In some cases, the fin and the tube may be made of the same metal material or different metal materials.

  As a metal material, Preferably, the metal material containing aluminum, ie, an aluminum containing metal, can be mentioned. Here, the aluminum-containing metal is generally an aluminum alloy containing aluminum in an arbitrary ratio. However, in some cases, the aluminum-containing metal may be a metal material containing aluminum in another form. A typical aluminum-containing metal is an Al—Mn alloy as described above.

  The fins and tubes are usually formed from a single layer or a single metal material, but may be composed of a composite of at least two layers of metal material if desired. In such a metal composite, it is preferable that the amount of the metal material having a noble oxidation-reduction potential increases from the upper metal material layer to the lower metal material layer. This is because by introducing the inclined oxidation-reduction potential into the metal material constituting the substrate, it is possible to effectively prevent undesired oxidation of the substrate during use of the heat exchanger. When a metal composite having a three-layer structure is employed, the third metal material layer disposed in contact with the surface polyaniline layer is compared with the redox potential of the first and second metal material layers below it. In this case, an arbitrary redox potential can be set in a range from a value that is most noble or more base to a value that is noble than the most base.

  FIG. 6 shows an example in which the base 1 of the fin 17 is composed of a composite of two layers of metal material. As shown in the figure, the substrate 1 is composed of a lower metal material layer 11 and an upper metal material layer 12. Although this example is an example of the base 1 of the fin 17, the present invention is not limited to this example, and the same applies to the other fins 17, but the base of the tube is similarly formed with the lower metal material layer 11. Or an upper metal material layer 12.

  In the illustrated metal material composite, the lower metal material layer is preferably made of an aluminum (Al) alloy, and the upper metal material layer is preferably made of a zinc (Zn) -containing metal material. Further, the lower metal material layer is preferably made of an Al—Mn alloy, and the upper metal material layer is preferably made of a metal material containing silicon (Si) in addition to zinc. In particular, the upper metallic material layer preferably consists of aluminum (Al) and an aluminum alloy containing negligible amounts of impurities in addition to zinc and silicon. Such an Al—Zn—Si alloy is commercially available, for example, from Kobe Steel Co., Ltd. under the trade name “4000 Series”.

  The surface polyaniline layer 2 may further have a dopant DP dispersed in the layer as schematically shown in FIG. When it is used in the present invention, the dopant can exhibit a bonding action or the like that favorably bonds the polyaniline to the underlying substrate, and thus can also be referred to as a “binder”. The dopant is preferably attached to the polyaniline and / or its derivative by electrostatic interaction. Explaining this with reference to the general formula of polyaniline described above, the dopant is attached to the nitrogen atom of the -NH- group between adjacent benzene rings or the nitrogen atom between adjacent benzene rings and polyaniline rings. Is common.

  When the surface polyaniline layer is provided according to the present invention, an interlayer intermediate layer may be further provided between the surface polyaniline layer and the underlying substrate. FIG. 8 is a partial enlarged cross-sectional view showing an example of such a heat exchanger, and the fin 17 has an interlayer intermediate layer 3 between the surface polyaniline layer 2 and the underlying substrate 1 as shown in the figure. In addition. The interlayer interlayer usually has a function of increasing the adhesion of the surface polyaniline layer to the substrate and a function of preventing the removal of electrons by the polyaniline (rust prevention).

  The interlayer interlayer can be formed from various materials, but is preferably made of a non-metallic material. Examples of suitable interlayer interlayers include, for example, an insulating film, an antioxidant film, a nonmetallic material having a redox potential nobler than that of a polyaniline compound, and more specifically, for example, a chromate film, Examples thereof include a polyamide film. The interlayer interlayer is usually used as a single layer, but if necessary, two or more interlayer interlayers may be used in combination. The thickness of the interlayer interlayer is not particularly limited.

As already described, in the present invention, the polyaniline in the surface polyaniline layer and (or) the peak intensity I ₁ and the Raman shift 1415cm ^-1 ± 30cm located Raman shift 1215 cm ^-1 ± 30 cm ^-1 in the Raman spectrum of the derivative ^{- The} polyaniline molecular structure ratio represented by the ratio I ₂ / I ₁ of the peak intensity I ₂ located at ¹ is usually in the range of about 0.75 to about 1.0, more preferably about 0.8 to about 1 In the range of .0. As shown in FIG. 9, when the peak intensity ratio I ₂ / I ₁ is less than 0.75, although the active oxygen generation ability is high, the surface polyaniline layer is likely to be peeled off rapidly, which is not preferable. On the other hand, if the peak intensity ratio I ₂ / I ₁ exceeds 1.0, the hydrogen peroxide generation concentration is significantly lowered, which is not preferable.

Therefore, it is important to retain in the range of the peak intensity ratio I ₂ / I ₁ of about 0.75 to about 1.0, in other words, the peak intensity ratio I ₂ / I ₁ at the surface polyaniline layer is 0. It is important to adjust the film forming conditions so as not to deviate from the setting range of 75 to 1.0. Incidentally, when the peak intensity ratio I ₂ / I ₁ is out of the setting range of 0.75 to 1.0, in order to return to within the set range and the peak intensity ratio I ₂ / I _1, polyaniline and (or) its It is preferable that a benzenoid-quinoid structure constituting the derivative is converted into a benzenoid-benzenoid structure, or a structure converting means for converting the benzenoid-benzenoid structure into a benzenoid-quinoid structure is further provided as necessary.

As shown in FIG. 10, in the present invention, by adjusting the film forming conditions, particularly the heating conditions, peeling of the surface polyaniline layer is suppressed by crosslinking, and the active oxygen generating ability is maintained within a predetermined range. In order to maintain a balance between the benzenoid-quinoid structure and the benzenoid-benzenoid structure that enables the polyaniline molecule represented by the ratio I ₂ / I ₁ of the peak intensity I ₂ in the Raman spectrum of polyaniline and / or its derivatives The structure ratio is in the range of 0.75 to 1.0.

  In addition, as shown in FIG. 10, in the state where the benzenoid-benzenoid structure is increased, NN bonds are easily generated between adjacent benzenoid structures, and thus there are many NN bonds. A certain surface polyaniline layer is difficult to peel off and can be a surface polyaniline layer having excellent durability.

  The above-described results cannot be achieved if there are micro defects such as pinholes in the surface polyaniline film and unformed portions of the surface polyaniline film. This is because if the solution used in the subsequent steps directly enters the base of the heat exchanger, it causes peeling of the surface polyaniline film and deterioration of characteristics. Therefore, there is a need for a film formation state evaluation step for evaluating whether there are any defects or undeposited portions after the surface polyaniline film is formed. After this step, the surface polyaniline film having defects and undeposited portions can be removed. For example, as a pinhole detection method, a predetermined measurement point is observed with an optical microscope, an image is taken in as electronic data, and binarized with image processing software (white: aluminum substrate, pinhole; black: polyaniline) Pinholes can be easily found in a short time by detecting the white part. In addition, in order to prevent the progress of pitting corrosion due to the occurrence of pinholes even at the time of non-manufacturing, if polyaniline is formed after forming a metal having a higher oxidation-reduction potential than chromate or polyaniline as a base film, the problem of corrosion will be caused. Can be reduced.

  Incidentally, when the surface of a metal material such as aluminum, iron, zinc or the like is coated with a water-absorbing polymer, preferably a polyaniline thin film, according to the technique described in JP-A-8-500770 described above. However, there is no problem if it is completely covered, but if some of the polyaniline film breaks down and the underlying passive metal material is exposed, electrons are taken away from the exposed metal material, and the exposed part Cause intensive corrosion. If this corrosion occurs in the tube of the heat exchanger, the refrigerant leaks or scatters from the pores (pinholes, etc.) of the corrosion portion, and the function as the heat exchanger is impaired. In particular, the one described in Japanese Patent Publication No. 8-500770, which is a polyaniline film that can be easily removed, is considered to be highly possible.

  The heat exchanger of the present invention can be manufactured according to various techniques, and an example thereof will be described below. First, an aluminum material is molded to produce heat exchange members such as tube members, fins, and plates, and these members are brazed at a high temperature of 600 ° C. or higher to form a heat exchanger having a desired shape. A precursor is prepared. Next, the brazing agent used for joining the members is washed and removed from the precursor using acid, alkali or the like, further washed with running water, drained and dried. Drying is performed, for example, at 140 ° C. for 15 minutes.

  Next, polyaniline is deposited on the surface of the precursor of the heat exchanger. For this film forming process, the precursor of the heat exchanger is immersed in a solution containing polyaniline for about 60 seconds, followed by draining and drying. The polyaniline-containing solution used here can have the following composition, for example.

Polyaniline about 0.1 to about 2% by weight Binder (carbodiimide compound) about 0 to about 20% by weight Solvent (water or organic solvent) about 80 to about 99.9% by weight

  Here, a drying process performs primary drying including an air drying process as needed, for example for 5 to 20 minutes at 60-80 degreeC, and then performs secondary drying for 5 to 20 minutes at 130-150 degreeC. . If this dry state is not sufficient, the polyaniline film may be peeled off in the subsequent steps. Therefore, it is preferable to confirm at this stage that the dry state is sufficient. After drying, the desired surface polyaniline film is obtained with a film thickness of about 0.5 μm.

  In addition, in order to prevent the solution used in the subsequent steps from directly entering the heat exchanger, a film formation state evaluation process is performed to evaluate whether or not there is an undeposited portion after the polyaniline film is formed. Is also preferable. In the film formation state evaluation process, for example, as described above, a predetermined measurement point is observed with an optical microscope, an image is taken as electronic data, and binarized with image processing software (white: aluminum substrate, pinhole, black : Polyaniline) can be easily carried out in a short time by detecting the white portion. After this step, it is possible to remove only the polyaniline film in which an undeposited portion (pinhole) is observed. In order to prevent the progress of pitting corrosion due to the generation of pinholes, if polyaniline is formed after forming a metal having a higher oxidation-reduction potential than chromate or polyaniline as a base film, the problem of corrosion is reduced.

  In the heat exchanger having the finned tube made of the aluminum material and the surface polyaniline layer covering the aluminum material produced as described above, a special electrode structure is attached to change the structural ratio of the polyaniline. The electrode structure is composed of, for example, a power source and an anode and a cathode connected to the power source, and the surface of each electrode is coated with a material having a redox potential higher than that of polyaniline. A voltage is applied from the power source to the electrode structure. In the case of the present invention, in order to enable the application of a potential and the application of a reverse potential, for example, a voltage opposite to that in use is applied to the electrode structure before and after use. It is preferable to provide a mechanism and a timer capable of controlling the application time to a certain time.

  Subsequently, the present invention will be described with reference to examples thereof. Needless to say, the present invention is not limited to these examples.

Production of Finned Tube An aluminum alloy (AlMn-based alloy) was molded to produce a tube and a fin partially shown in FIG. Fins were brazed to the tube. The brazing temperature was about 600 ° C. After confirming the joining of the two, the used brazing agent was dissolved and removed with dilute sulfuric acid, and further sufficiently washed with running water. After draining, the obtained precursor was dried at 140 ° C. for 15 minutes.

Next, a polyaniline film was formed on the surface of the precursor after drying. The composition of the polyaniline-containing solution used in this example was as follows.
Polyaniline (trade name “Polyaniline, emeraldine base” from Aldrich) about 0.1 to about 2% by weight Binder (carbodiimide compound) about 0 to about 20% by weight Solvent (water or organic solvent) about 80 to about 99. 9% by weight

  The precursor was immersed in the polyaniline-containing solution (liquid temperature: about 20 ° C.) for about 60 seconds, followed by liquid draining and drying. The primary drying process was at 80 ° C. for 15 minutes, and the secondary drying process was at 140 ° C. for 15 minutes. A finned tube having a surface polyaniline film having a film thickness of about 0.5 to about 10 μm over the entire surface was obtained.

Use in Heat Exchanger The obtained finned tube was used as an automobile heat exchanger as shown in FIG. 1 and its performance was examined. As a result, it was confirmed that the finned tube has excellent durability and also has a function of decomposing odorous substances adhering to the surfaces of the tube and the fin and a function of sterilizing harmful microorganisms. In addition, the decomposition and deodorization function of odorous substances and the sterilization function of organic microorganisms can be generated efficiently, and by maintaining the ratio of benzenoid-benzenoid structure to benzenoid-quinoid structure in polyaniline, It was also confirmed that the adhering odor can be suppressed and the basic performance of the heat exchanger can be maintained without causing peeling of the polyaniline layer after use or reducing the active oxygen generation ability of the polyaniline.

Evaluation test The following evaluation test was carried out on the obtained finned tube in order to evaluate the change over time of the peak intensity ratio I ₂ / I ₁ , active oxygen generation ability and peeled state of the surface polyaniline layer.

(1) Peak intensity ratio I ₂ / I ₁
The peak intensity ratio I ₂ / I ₁ of the surface polyaniline layer of the sample of the polyaniline layer on the surface of each sample after the film formation as described above was determined using a Raman spectrum measuring instrument NSR-3000 (trade name) manufactured by JASCO Corporation. to obtain a Raman spectrum with the peak intensity ratio of the peak intensity I ₂ is located in the peak intensity I ₁ and the Raman shift 1415cm ^-1 ± 30cm ^-1 located Raman shift _{^{1215cm -1 ± 30cm -1 I 2 /}} I 1 It was measured. The Raman spectrum was measured under the conditions of an exposure time of 30 seconds, an integration number of 2 times, an excitation wavelength of 532 nm, a grating of 1800 L / mm, and a laser intensity of 0.8 mW. Examples of the measured Raman spectrum are shown as S1 to S3 in FIG.

(2) Active oxygen generation ability The hydrogen peroxide concentration in the eluate of the polyaniline layer on the surface of each sample after film formation was measured as the active oxygen generation concentration. That is, after performing the Fenton reaction, radicals were trapped in a spin trap agent (DMPO) and measured by NSR-3000 to evaluate the ability to generate active oxygen.

(3) Peelability The peelability of the polyaniline layer on each sample surface after film formation was measured by the following procedure.
Using a cutter knife, parallel lines with 1 mm vertical and horizontal intervals are drawn on the polyaniline film 31 so that the base of the polyaniline film 31 is exposed (see FIG. 11A). The grid is partitioned by 11 parallel lines, and the polyaniline film is divided into 100 units U with a size of 1 mm × 1 mm.
Adhesive tape 32 is sufficiently adhered to the surface of polyaniline film 31 on fin material 30 so as to cover this grid portion (see FIG. 11B). The size of the adhesion region of the adhesive tape 32 on the polyaniline film 31 is, for example, about 20 mm × 24 mm as shown as a numerical value.
Next, the adhesive tape 32 is peeled off at once. At this time, the number of units U of the polyaniline film 31 that are attached to the tape 32 and peeled off together is counted. The greater the number of counted units U, the worse the adhesion of the polyaniline film, and the smaller the number, the better the adhesion.

(4) Summary Based on the results obtained by the above measurement, the active oxygen generation concentration (ppm) and the peelability of the polyaniline film are plotted as a function of the peak intensity ratio I ₂ / I ₁ . I was able to get a graph like this. As can be understood from this graph, the peak intensity ratio I ₂ / I ₁ is preferably in the range of 0.75 to 1.0, and more preferably in the range of 0.8 to 1.0.

It is the schematic cross section which showed an example of the evaporator for motor vehicles using the heat exchanger of this invention. It is the fragmentary sectional view which showed one preferable form of the heat exchanger of this invention. FIG. 3 is an enlarged partial cross-sectional view showing a part of a fin of the heat exchanger shown in FIG. 2. It is the graph which illustrated the measurement result of the typical Raman spectrum of polyaniline in the surface polyaniline layer in the heat exchanger of the present invention. It is the expanded partial sectional view which showed another preferable form of the fin of the heat exchanger of this invention. It is the expanded partial sectional view which showed another preferable form of the fin of the heat exchanger of this invention. It is the expanded partial sectional view which showed another preferable form of the fin of the heat exchanger of this invention. It is the expanded partial sectional view which showed another preferable form of the fin of the heat exchanger of this invention. It is a graph plotting the relationship between the peeling of the peak intensity ratio I ₂ / I ₁ against active oxygen generator concentration and polyaniline layer on the surface polyaniline layer of the present invention. This is a chemical formula showing a change from a benzenoid-quinoid structure to a benzenoid-benzenoid structure due to heating when a polyaniline layer is formed. It is explanatory drawing for showing the procedure which evaluates the peelability of a surface polyaniline layer.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate 2 Surface polyaniline layer 3 Interlayer intermediate layer 10 Heat exchanger 11 Lower metal material layer 12 Upper metal material layer 15 Tube 16 Refrigerant 17 Fin

Claims (23)

In a member with a surface coating comprising at least a substrate and a surface coating formed on at least a part of the outermost surface of the substrate,
The surface coating is a surface polyaniline layer composed of polyaniline and / or a derivative thereof capable of generating active oxygen or hydrogen peroxide by reacting with moisture in a fluid brought into contact therewith, and the polyaniline and / or the polyaniline represented by the ratio I ₂ / I ₁ of the peak intensity I ₂ is located in the Raman shift 1215 cm ^-1 peak intensity located ± 30 cm ^-1 I ₁ Raman shift 1415cm ^-1 ± 30cm ^-1 in the Raman spectrum of the derivative The molecular structure ratio is in the range of 0.75 to 1.0,
A member with a surface coating characterized by the above. The polyaniline or derivative thereof has the following general formula:

The member with a surface coating according to claim 1, wherein the member is selected from the group consisting of polyaniline having a benzenoid structure and a quinoid structure, and derivatives thereof. The member with a surface coating according to claim 1 or 2, wherein the structural ratio represented by the peak intensity ratio I ₂ / I ₁ is in a range of 0.8 to 1.0.   The member with a surface coating according to any one of claims 1 to 3, wherein the member with a surface coating is a member for a heat exchanger. It comprises at least a substrate and polyaniline and / or its derivative formed on at least a part of the outermost surface of the substrate and capable of generating active oxygen or hydrogen peroxide by reacting with water in a fluid brought into contact therewith. surface polyaniline layer der is, and the polyaniline and (or) peak located at the peak intensity I ₁ and the Raman shift 1415cm ^-1 ± 30cm ^-1 located Raman shift 1215 cm ^-1 ± 30 cm ^-1 in the Raman spectrum of the derivative A method for producing a member with a surface coating comprising a surface coating , wherein the polyaniline molecular structure ratio represented by the ratio I ₂ / I ₁ of strength I ₂ is in the range of 0.75 to 1.0 ,
Applying a solution containing less than 2% by weight of the polyaniline and / or its derivative to the surface of the substrate;
A primary drying step of drying the substrate to which the solution is applied at 60 to 80 ° C . ;
A secondary drying step of further drying the primary dried substrate at 130 to 150 ° C., and
After the secondary drying process, the polyaniline and (or) peak located at the peak intensity I ₁ and the Raman shift 1415cm ^-1 ± 30cm ^-1 located Raman shift 1215 cm ^-1 ± 30 cm ^-1 in the Raman spectrum of the derivative Measuring intensity I ₂ ;
The manufacturing method of the member with a surface film characterized by including. When the measured peak intensity ratio I ₂ / I ₁ is out of the setting range of 0.75 to 1.0, in order to make the peak intensity ratio I ₂ / I ₁ within the set range, the polyaniline And / or further comprising a structural conversion step of converting a benzenoid-quinoid structure to a benzenoid-benzenoid structure or converting a benzenoid-benzenoid structure to a benzenoid-quinoid structure that constitutes a derivative thereof. Manufacturing method of member with surface coating. In heat exchangers with finned tubes,
The tube and / or fin comprises at least a substrate and a surface coating formed on at least a part of the outermost surface of the substrate,
The surface coating is a surface polyaniline layer composed of polyaniline and / or a derivative thereof capable of generating active oxygen or hydrogen peroxide by reacting with moisture in a fluid brought into contact therewith, and the polyaniline and / or the polyaniline represented I ₂ / I ₁ ratio of the peak intensity I ₂ is located in the peak intensity I ₁ and the Raman shift 1415cm ^-1 ± 30cm ^-1 located Raman shift 1215 cm ^-1 ± 30 cm ^-1 in the Raman spectrum of the derivative The molecular structure ratio is in the range of 0.75 to 1.0,
A heat exchanger characterized by that. The polyaniline or derivative thereof has the following general formula:

The heat exchanger according to claim 7, wherein the heat exchanger is selected from the group consisting of polyaniline having a benzenoid structure and a quinoid structure and a derivative thereof, represented by: The heat exchanger according to claim 7 or 8, wherein the structure ratio represented by the peak intensity ratio I ₂ / I ₁ is in a range of 0.8 to 1.0.   The heat exchanger according to any one of claims 7 to 9, wherein the surface polyaniline layer further has at least one hydrophilic functional group imparted thereto.   The at least one hydrophilic functional group is selected from the group consisting of a primary amino group, a secondary amino group, a tertiary amino group, an ammonium group, a nitric acid group, a carboxyl group, a sulfonic acid group, and a hydroxyl group. The heat exchanger according to any one of claims 7 to 10.   The said at least 1 sort (s) of hydrophilic functional group originates in the binder used together when forming the said surface polyaniline layer from the said polyaniline and / or its derivative (s), The any one of Claims 7-11 Heat exchanger   The heat exchanger according to claim 12, wherein the at least one hydrophilic functional group has been previously imparted to the binder.   The heat exchanger according to any one of claims 7 to 13, wherein the tube and / or the fin base is formed by molding a metal material.   The tube and / or fin base is composed of a composite of at least two layers of metal material, and in the composite, the redox potential is noble from the upper metal material layer to the lower metal material layer. The heat exchanger according to any one of claims 7 to 14, wherein an amount of a simple metallic material is increased.   The tube and / or fin base comprises a composite of two layers of metal material, wherein the lower metal material layer comprises an aluminum (Al) alloy and the upper metal material layer comprises The heat exchanger according to any one of claims 7 to 15, comprising a zinc (Zn) -containing metal material.   17. The heat according to claim 16, wherein the lower metal material layer is made of an Al—Mn-based alloy, and the upper metal material layer is made of a metal material containing silicon (Si) in addition to zinc. Exchanger.   The heat exchanger according to any one of claims 7 to 17, wherein the surface polyaniline layer further contains a dopant.   19. A heat exchanger according to claim 18, wherein the dopant is attached to the polyaniline and / or its derivative by electrostatic interaction.   20. A heat exchanger according to any one of claims 7 to 19, wherein the tube and / or fin further comprises at least one interlayer interlayer between the substrate and the surface polyaniline layer.   The at least one interlayer intermediate layer is selected from the group consisting of an insulating film, an antioxidant film, and a film made of a nonmetallic material having a redox potential nobler than that of the polyaniline and / or its derivative. The heat exchanger according to 20.   The heat exchanger according to any one of claims 7 to 21, further comprising the surface polyaniline layer on the outermost surface of the tube.   The heat exchanger according to any one of claims 7 to 22, which is used for a car air conditioner.

Images