JP5202467B2 - Blower - Google Patents

Description

  The present invention relates to an air blower, an air conditioner, and a coating composition that simultaneously realize prevention of adhesion of various types of dirt, prevention of mold generation, and dew splatter on resin parts such as an air blower fan.

  In an air conditioner that performs indoor air conditioning, resin parts such as the blower fan, casing (which constitutes the air path), and wind direction control plate around the air outlet are exposed to various types of dirt and heat exchange. Exposed to later cold air. When these resin parts are cooled to below the dew point temperature of the room air around the air conditioner, condensation occurs, and if the operation is continued for a long time, the condensed water grows into large droplets and eventually drops to wet the floor. End up. In addition, even if it does not drip, it retains water droplets and does not dry for a long time. It was.

  Since various kinds of dirt such as dust, dust, oil smoke and cigarette dust adhere to the surface of various articles used indoors and outdoors, various methods for suppressing this have been proposed. For example, a method is known in which an antistatic agent is coated on the surface of an article or an oil repellent fluororesin is coated to easily prevent and remove lipophilic dirt. In coatings used in air conditioners, photocatalytic oxides and water-repellent fluororesin are microscopically dispersed on the surface to prevent water droplet bridging to the heat exchanger and exposed to contact with the outside air. An antifouling coating composition has been proposed in which the surface of the layer has a contact angle θ with water of 90 ° or more (see, for example, Patent Document 1).

  Further, a heat exchanger fin having a hydrophilic antifouling layer (not described in detail) on a resin-based hydrophilic layer containing an antifungal agent such as zinc pyrithione has been proposed (see, for example, Patent Document 2).

  Further, in order to prevent mold and fungi from being generated on the surface, usually, in resin parts, a resin material is often kneaded with a material having an antifungal or antibacterial action.

Japanese Patent Laid-Open No. 10-132483 JP 2008-202931 A

  The antifouling coating composition of Patent Document 1 is partially hydrophilic due to photoexcitation caused by irradiating the photocatalytic oxide with light, and good antifouling when light irradiation is not sufficient. There was a problem that performance could not be obtained.

  Moreover, since it is a coating film having a contact angle with water of 90 degrees or more, when applied to a resin part, a water droplet rolls and undesirably causes a dripping problem.

  Further, this coating film does not have an antifungal action. Therefore, a method capable of simultaneously imparting high antifouling performance, high anti-sagging and antifungal properties to the resin portion has not been discovered so far.

  The heat exchanger fin provided with the hydrophilic antifouling layer of Patent Document 2 may be a heat exchanger that can be washed away because of the hydrophilic antifouling layer, but the resin component has the same hydrophilic property. Dirt (dust, sand dust, etc.) that you have adheres well.

  In addition, in the case of hydrophilicity, water droplets spread and slide down. When the dirt accumulates, not only the condensed moisture is held in the dirt and is difficult to evaporate, but also there is an increased risk that an environment suitable for mold growth such as dirt, moisture, air, and high humidity as nutrients will be established.

  In addition, although the lower layer is equipped with a fungicide that elutes, the elution type requires control of the amount of elution and has good initial performance but poor long-term reliability.

  Moreover, since it is not exposed to the surface, the contact degree with the microbe adhering to the surface is low.

  Further, in the case where a mold-proof or antibacterial material is kneaded into the resin material, the mold-proof effect is low because the material does not come out well on the surface (because the surface concentration is low).

  Therefore, there is a need for a method that can prevent adhesion of various amphiphilic soils and increase the contact ratio with mold on the surface.

  An amphiphilic molecule is a general term for molecules having a “hydrophilic group” that conforms to water and a “lipophilic group” (hydrophobic group) that conforms to oil in one molecule.

  In addition, to prevent the adhesion of various amphiphilic soils, it is effective to prevent the surface from being caught. However, if particulate materials such as anti-fungal agents are large, they become a cause of the soiling. Therefore, there are many cases where the antifouling property cannot be obtained even if the antifungal property is obtained.

  Moreover, in order to prevent dripping, there is a problem even if the surface state becomes too hydrophobic as in Patent Document 1 or becomes too hydrophilic as in Patent Document 2.

  It is useful if the prevention of dirt, prevention of mold, and prevention of dripping are improved in each resin part. Especially in the blower fan, dirt accumulates due to inertial collision, Brownian motion, and electrostatic adhesion. Mold grows from the edge of the blade near the tip of the blade, grows from the blade end, and fills the air outlet of the blade. As a result, there is a problem that the air blowing performance and the energy saving performance are remarkably deteriorated and a bad odor is directly transmitted to the user.

  The present invention was made to solve the above-described problems, and resin parts have an antifouling performance against various types of dirt, a suppression of dew splatter and dripping, a suppression of dew retention, and an antifouling performance. Provided are an air blower, an air conditioner and a coating composition to which a coating composition capable of simultaneously providing effective antifungal performance is not provided.

The blower according to the present invention is a blower fan that sucks air and blows out the sucked air,
A coating composition coated on the surface of the blower fan and having antifouling properties;
The coating composition is
One or both of hydrophilic inorganic fine particles and hydrophobic resin particles for imparting antifouling properties in an aqueous medium, and fungicides or antibacterials that are atomized until the average particle size is 10 μm or less And particles having an action,
The aqueous medium applied to the blower fan is dried to coat the surface of the blower fan,
Particles having fungicidal or antibacterial action are dispersed on the surface of the coating composition.

  In the blower according to the present invention, the coating composition coated on the surface of the blower fan is either one of hydrophilic inorganic fine particles and hydrophobic resin particles for imparting antifouling properties in an aqueous medium. Alternatively, both of them are mixed with anti-fungal or antibacterial particles that are atomized until the average particle size is 10 μm or less, and the aqueous medium applied to the blower fan is dried to coat the surface of the blower fan. Since particles with fungicidal or antibacterial action are dispersed on the surface of the coating composition, repulsion due to amphoteric, reduced adhesion area due to micro uneven structure, prevention of electrostatic adhesion due to antistatic effect It can prevent sticking due to low density and low intermolecular force, and prevent various stains regardless of hydrophilicity or hydrophobicity.

FIG. 5 shows the first embodiment, and is a vertical cross-sectional view at a substantially central portion in a side view schematically showing the air conditioner 100. The longitudinal cross-sectional view which shows the to-be-coated part of the air conditioner 100 shown in FIG. FIG. 5 is a diagram illustrating the first embodiment, and is a conceptual diagram illustrating a cross section in a state where a coating component 200 is coated on a resin part to be coated and a coating film 103 is formed. Only the portion of the coating film 103 by the coating composition 200 in FIG. 3 is shown. The conceptual diagram which looked at the upper surface of the coating film 103 of FIG. 3 or FIG. FIG. 3 is a diagram illustrating the first embodiment, and is a conceptual diagram illustrating a cross section in a state where a coating composition 200 including a fungicide is coated on a resin surface and a coating film 103 is formed. The conceptual diagram which looked at the upper surface of the coating film 103 of FIG. The figure which shows Embodiment 1 and is a figure which shows the particle size distribution and frequency at the time of using thiabendazole (TBZ) which is a general purpose antifungal agent as an example of an antifungal agent. FIG. 5 is a diagram illustrating the first embodiment and is a schematic diagram illustrating a contact angle θ of a water droplet 50 attached to a resin surface. FIG. 3 is a diagram illustrating the first embodiment, and is a conceptual diagram illustrating a cross section in a state where a coating composition 200 to which a radical generating material 111 or a peroxide 112 is added is coated on a resin surface and a coating film 103 is formed. The figure which shows Embodiment 1 and is a figure showing the particle size distribution at the time of atomizing the BPO (benzoyl peroxide; oil-soluble) as a radical material, and its frequency. FIG. 5 shows the first embodiment and is a cross-sectional view showing an unused normal blower fan 20. FIG. 3 is a diagram showing the first embodiment, and is a cross-sectional view showing a blower fan 20 with mold. In the figure which shows Embodiment 1, the density | concentration of the antifungal agent in the position of the braid | blade 21 of the ventilation fan 20 at the time of rotating the ventilation fan 20 and equalizing the density | concentration of the antifungal agent without approaching the position of the blade 21 is shown. FIG. FIG. 5 is a diagram illustrating the first embodiment, and the blower fan in a case where the blade tip portion 24 is inclined so as to increase in concentration from the inner peripheral portion 27 of the blade 21 constituting the blower fan 20 toward the blade tip portion 24. The figure which shows the density | concentration of the fungicide in the position of 20 blades 21. FIG. FIG. 5 shows the first embodiment, and shows the concentration of the fungicide at the position of the blade 21 of the blower fan 20 when the blower fan 20 is rotated faster.

Embodiment 1 FIG.
Hereinafter, the air conditioner, the blower, and the coating composition according to Embodiment 1 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 a part of the description is omitted.

  FIG. 1 is a view showing the first embodiment, and is a longitudinal sectional view in a substantially central portion in a side view schematically showing the air conditioner 100. FIG.

In FIG. 1, the air conditioner 100 includes at least the following constituent members.
(1) A casing 10 that forms an outline of the air conditioner 100 (indoor unit);
(2) A blower fan 20 installed in the housing 10 for sucking air and blowing the sucked air;
(3) A casing portion 15 for guiding the wind blown by the blower fan 20;
(4) a heat exchanger 30 that harmonizes the sucked air by exchanging heat with the refrigerant of the refrigeration cycle;
(5) Filter 40 for capturing dust contained in the sucked air; (6) Left and right vanes 13 for bending the air blown into the room in the left-right direction;
(7) Upper and lower flaps 17 that bend the wind blown into the room in the vertical direction;
(8) Openable front grill 12;
(9) A nozzle 18 that forms an air passage with the casing portion 15.

  Hereinafter, each component will be described individually. The blower fan 20 is disposed in a substantially central portion in a side view of the housing 10 and is disposed in an air path extending from the suction port 11 to the blowout port 14. A once-through fan is used as the blower fan 20.

  The casing part 15 determines the blowing direction of the blower fan 20 and extends from the rear of the blower fan 20 to the blower outlet 14.

  The heat exchanger 30 is disposed between the suction port 11 and the blower fan 20 and harmonizes (cooling, heating, dehumidifying, blowing, etc.) by exchanging the sucked air with the refrigerant of the refrigeration cycle.

  The heat exchanger 30 is a finned tube heat exchanger that includes a heat transfer tube 31 and radiating fins 32 through which the heat transfer tube 31 is inserted.

  Moreover, although the heat exchanger 30 does not attach | subject the code | symbol, it is a substantially reverse V shape (cross-sectional shape of a side view) which consists of a front upper heat exchanger, a front lower heat exchanger, and a back heat exchanger.

  There is a case where wind having a high wind speed collides with the casing portion 15, and dew flying through the heat exchanger 30 adheres. Further, in the vicinity of the suction side of the casing portion 15 close to the blower fan 20, if heat insulation from the back surface of the housing 10 is insufficient or warm air enters, dew often adheres in a horizontal row.

  The left and right vanes 13 are flat wind direction plates of various outer shapes formed of resin, and a plurality of left and right vanes 13 are installed in the width direction (left and right direction) of the indoor unit (referred to as the air conditioner 100 in FIG. 1) and blown out. It has a role to send the wind that has been sent to the left and right.

  The upper and lower flaps 17 are wind direction plates having a substantially arc-shaped cross section formed of resin, and are installed across the width direction (left and right direction) of the air outlet 14 of the indoor unit, and serve to send the blown wind up and down. have.

  The left and right vanes 13 and the upper and lower flaps 17 can be automatically changed in angle by a motor (not shown). The upper and lower flaps 17 may be divided into an upper flap and a lower flap, or a plurality of upper and lower flaps 17 may be provided.

  In the figure, the heat exchanger 30 is disposed so as to surround the top surface side and the front surface side of the blower fan 20, but the present embodiment is not limited to the disposition form.

  Moreover, although the heat exchanger 30 has shown as an example what has the heat exchanger tube 31 and the radiation fin 32 by which the heat exchanger tube 31 is penetrated, this Embodiment is not limited to this.

  Moreover, although the air conditioner 100 in a figure is a wall-hanging type, this Embodiment is not limited to this.

  The coating of the present embodiment described below can be applied not only to the air conditioner 100 but also to a blower.

  Hereinafter, a resin coating composition that exhibits excellent antifouling performance for both the hydrophilic fouling substance 105 and the hydrophobic fouling substance 106 will be described with reference to the drawings.

  FIG. 2 is a longitudinal sectional view showing a portion to be coated of the air conditioner 100 shown in FIG. A portion to be coated which is effective when the coating composition 200 of this embodiment is applied is surrounded by a thick black line.

  In FIG. 2, the resin components of the blower fan 20, the casing portion 15, the left and right vanes 13, and the upper and lower flaps 17 indicated by a thick black line or surrounded by a thick black line are likely to be dewed. At the same time, it is a suitable site to which the coating composition 200 of the present embodiment is applied, because the fungus such as black mold and blue mold easily adheres due to the moisture caused by dew and the various stains attached. Moreover, since the dew is likely to be formed on the lower surface of the nozzle 18 when the direction of the top blowing air, the coating composition 200 may be applied.

  Even if it is a resin part that does not normally dew, it can be used in high-humidity air, even if it is an air passage through which steam passes, or a resin part used in bath-related, toilet-related, and ventilating fans. There is a case where it is exposed, and this is a suitable part to which the coating composition 200 of the present embodiment is applied.

  At the blade tip 24 of the blower fan 20 (FIG. 12), dirt particles frequently collide so that dirt is likely to accumulate, and when the moisture is retained, mold grows and the mycelium that has been extended for a long time. Fills the space between the blades, generates odors, and significantly reduces the air flow. Therefore, this is the most suitable site to which the coating composition 200 is applied.

  The casing portion 15, the left and right vanes 13, the upper and lower flaps 17, the nozzle 18, and the blower fan 20 (in particular, the blade tip portion 24) are collectively referred to as “resin parts provided on the downstream side of the heat exchanger”. .

  FIGS. 3 to 5 are diagrams showing the first embodiment, and FIG. 3 is a conceptual diagram showing a cross section in a state in which the coating composition 200 is coated on a resin part to be coated and a coating film 103 is formed. 4 is a conceptual diagram showing only a portion of the coating film 103 by the coating composition 200 in FIG. 3, and FIG. 5 is a conceptual view of the top surface of the coating film 103 in FIG. 3 or FIG. 3 to 5 all show a state in which the coating composition 200 is dried to form the coating film 103.

  In the dried state, the coating composition 200 of the first embodiment is dotted with hydrophobicity in the hydrophilic silica film 104 composed of the silica fine particles 101, but is not entirely but partially from the silica film 104. The coating film 103 having a configuration exposed to the surface is formed.

  The coating composition 200 is a hydrophilic / hydrophobic composite surface including both hydrophilic inorganic fine particles (silica film 104) and hydrophobic resin particles (fluorine resin particles 102).

Silica (SiO ₂ ) is an oxide of silicon that occupies about 60% of the earth's crust. It produces excellent properties in various fields by chemically reacting mainly with silica sand as a raw material to produce porous silica with a large surface area structure. Along with its chemical stability, it is in the spotlight in a wide range of fields.

  The coating composition 200 is obtained by mixing water (dispersion) in which the silica fine particles 101 are dispersed and water (dispersion) in which the fluororesin particles 102 are dispersed. Before the coating film 103 is formed, it is in a liquid state in which the silica fine particles 101 and the fluororesin particles 102 are dispersed in moisture. The coating film 103 is formed on the surface of the article by applying the dispersion (coating solution) on the article surface or immersing the article in the dispersion and then drying to remove moisture. is there. The silica film 104 in the coating film 103 is a film in which the bonding of silicon Si and oxygen O continues and has an OH group on the surface.

  Here, as shown in FIG. 4, the coating layer formed on the surface of the article by the coating composition 200 is referred to as a coating film 103.

  The coating film 103 is in a state where the fluororesin particles 102 are scattered in the silica film 104 made of the silica fine particles 101 and the fluororesin particles 102 are partially exposed from the surface of the silica film 104. It is what.

  In addition, here, the coating composition 200 basically refers to a state called a coating solution that is in the state of the dispersion described above.

  The average particle diameter (average particle diameter) of the silica fine particles 101 used in the coating composition 200 is 30 nm or less, preferably 4 to 15 nm when measured by a light scattering method. The particle size can be measured by a light scattering method. Thus, in the state of the coating solution dispersed in water, the silica fine particles 101 having an extremely small average particle diameter are in a state in which all the surface portions in contact with water are in equilibrium and are dissolved in water (the surface in contact). The part is a substance with an intermediate property between water and silica).

  When the coating composition 200 is dried, the semi-dissolved silica component functions as a binder (a binder that hardens the particles) that connects the silica fine particles 101 to each other. Therefore, even if no special binder is added, the silica fine particles 101 are easily aggregated and solidified after drying. Therefore, it is possible to obtain the silica film 104 that is excellent in strength, such as being hard to crack, and thus the coating film 103.

  In the silica fine particles 101 having an average particle diameter in the range of 4 to 15 nm, the surface portion corresponding to approximately 15 to 30% of the weight of the silica fine particles 101 is half water in the coating solution. It is in a dissolved state.

  However, in the case of the silica fine particles 101 having an average particle diameter of more than 15 nm, the larger the average particle diameter, the smaller the weight of the silica component that is semi-dissolved in water in the coating solution with respect to the weight of the silica fine particles 101, and the action as a binder. Can no longer be obtained. Therefore, the coating film 103 formed is not preferable as the coating film 103 because it does not have sufficient strength and cracks are easily generated. Therefore, it becomes necessary to add a binder separately.

  On the contrary, in the case of the silica fine particles 101 having an average particle size of less than 4 nm, the ratio of the silica component dissolved in the water becomes too high in the coating solution, and the silica fine particles 101 aggregate in the coating solution. For example, the stability as the coating composition 200 cannot be obtained. Also, the strength of the silica film 104 (coating film 103) formed after drying and the antifouling performance described later cannot be obtained.

  The particle size of the silica fine particles 101 also affects the appearance characteristics such as transparency of the coating film 103 to be formed. If the silica fine particles 101 have an average particle size of 15 nm or less, scattering of light reflected by the coating film 103 is reduced. Therefore, the transparency of the coating film 103 can be improved, the change in the color tone and texture of the coating object can be suppressed, and the color tone and texture of the coating object can be prevented from being impaired.

  Further, by using silica fine particles 101 having an average particle size of 15 nm or less as silica fine particles 101, the silica film 104 in the coating film 103 obtained has fine voids between the silica fine particles 101 while being dense. It becomes. Silicate (silicate refers to a compound containing an anion with a structure centered on one or several silicon atoms and surrounded by an electronegative ligand, also called silicate) or sol-gel method (generally metal A sol composed of an alkoxide is converted into a gel that loses fluidity by hydrolysis and polycondensation reaction, and a conventional silica film that does not use fine particles formed by heating the gel to obtain an oxide) Compared with a silica film to which a binder made of a soluble organic or inorganic material is added, the silica film 104 of the present embodiment can be formed thin, and the unevenness on the surface of the silica film 104 by the silica fine particles 101 can be made smooth and smooth. Since it can be formed, the fouling substance is not caught and the antifouling performance is improved.

  The content of the silica fine particles 101 in the coating composition 200 is 0.1 to 5% by weight, preferably 0.3 to 2.5% by weight with respect to the coating composition 200.

  Using the coating composition 200 having a content (concentration) in this range, a liquid film is formed on the surface of an object to be coated (for example, a resin part such as the casing portion 15, the left and right vanes 13, and the upper and lower flaps 17) by dipping or coating. When the coating is performed by a method in which excess coating solution is washed away or forcibly removed and dried, the thickness of the formed coating film 103 is about 50 to 500 nm, and the silica film 104 is The coating film 103 can be formed with a uniform thickness without unevenness and without impairing the color tone and texture of the surface of the object to be coated.

  When the content of the silica fine particles 101 is less than 0.1% by weight, the silica film 104 becomes too thin and partial defects occur, resulting in a portion that cannot be coated on the surface of the object to be coated. May occur, which makes the coating composition 200 unsuitable.

  On the other hand, if the content of the silica fine particles 101 exceeds 5% by weight, the silica film 104 becomes too thick to become a cloudy film, which impairs the color tone and texture of the surface of the object to be coated. Further, since the silica fine particle 101 itself has a large weight ratio, it becomes difficult to obtain a binder action due to the silica component dissolved in the half-water in the coating solution described above, and the solidified state of the silica fine particles 101 after drying becomes weak. The film 104 is inferior in strength, such as being easily cracked or easily peeled off.

  Next, the fluororesin particles 102 used in the coating composition 200 will be described. In the coating film 103, the average particle diameter (average particle diameter) of the fluororesin particles 102 that are scattered in the silica film 104 and partially exposed from the silica film 104 is not 50 to 500 nm, preferably 100. Those with ~ 250 nm are used. The particle size can be measured by a light scattering method. By using a particle having a particle diameter in such a range, the particle diameter becomes larger than the thickness of the silica film 104, and the fluororesin particles 102 are easily dispersed in the silica film 104 in the formed coating film 103. The fluororesin particles 102 are easily partially exposed on the surface of the coating film 103 (from the surface of the silica film 104), and a desired state of the coating film 103 can be obtained.

  When the fluororesin particles 102 have an average particle size of less than 50 nm, the stability of properties cannot be obtained, for example, the fluororesin particles 102 aggregate and coalesce in the coating solution. Further, in the coating film 103 to be formed, the fluororesin particles 102 are hardly exposed from the surface of the silica film 104, and the antifouling performance described later cannot be obtained.

  On the other hand, if the average particle diameter is the fluororesin particles 102 exceeding 500 nm, the portion of the fluororesin particles 102 exposed from the surface of the silica film 104 in the formed coating film 103 becomes large. In such a case, the region of the hydrophobic portion on the surface of the coating film 103 becomes too large, and the antifouling performance described later cannot be obtained. Moreover, the unevenness | corrugation of the coating film 103 surface becomes large too much, and a fouling substance (dirt) becomes easy to be caught, and the adhering fouling substance becomes difficult to be removed.

  In the coating film 103 formed by drying the coating composition 200 on the surface of the object to be coated, the thickness of the silica film 104 is smaller than the average particle diameter of the fluororesin particles 102. By managing the thickness of the silica film 104 to be smaller than the average particle diameter of the fluororesin particles 102, the fluororesin particles 102 are dispersed and dispersed in the silica film 104 in the coating film 103 to be formed, The silica film 104 can be partially exposed from the surface of the silica film 104, and a desired state of the coating film 103 can be obtained.

  For example, when the fluororesin particles 102 having an average particle diameter of 250 nm are used, the thickness of the silica film 104 is controlled to be less than 200 nm. That is, the thickness of the silica film 104 is made thinner than the average particle diameter of the fluororesin particles 102. Thus, in order to form the silica film 104 into a thin film having a thickness of less than 200 nm, the coating solution on the surface of the object to be coated may be blown with a strong air current before the silica fine particles 101 are solidified on the surface of the object to be coated. The thickness of the silica film 104 can be managed by adjusting factors such as the blow speed, blow time, and blow temperature.

  Hereinafter, the antifouling performance (antifouling property) by the coating film 103 formed by the coating composition 200 will be described. The term “dirt” means that a fouling substance adheres to the surface of the article and is fixed to the article surface without being removed. Therefore, it is possible to prevent the fouling substances from adhering to the surface of the article, and even if fouling substances adhere to the surface of the article, the fouling substances can be easily removed from the surface without adhering to the surface. This will prevent contamination.

  In this way, the property that the pollutant is difficult to adhere to the surface, and the property that it can be easily removed (removed) from the surface without adhering to the surface even if the soiled material adheres, is called “antifouling performance”. Shall be called.

  By coating the surface of the article, the coating composition 200 (coating film 103) that can make the article surface excellent in the antifouling performance has a high antifouling performance or an excellent antifouling performance. It shall be expressed as film 103).

  The term “attachment” refers to a state where it can be relatively easily removed from the surface, including a state where it is simply placed on the surface. “Fixed” refers to a state that cannot be easily removed from the surface, and is used separately.

  The pollutants that cause dirt include a hydrophilic pollutant 105 and a hydrophobic pollutant 106. The hydrophilic fouling substance 105 is likely to adhere to a portion showing hydrophilicity and difficult to adhere to a portion showing hydrophobicity. And the hydrophobic fouling substance 106 is the opposite.

  The hydrophilic fouling substance 105 is dust, dust, or the like. The hydrophilic fouling substance 105 and the hydrophilic fouling substance 105 and the hydrophilic portion (OH group) present in the hydrophilic portion of the article surface are electrostatically coupled to each other, or the hydrophilic fouling substance 105 It adheres to the hydrophilic part of the article surface (including the surface of the coating film 103) by intermolecular force due to the proximity of the substance 105 and the hydrophilic part of the article surface, or by liquid cross-linking with a liquid such as water. .

  Sand dust, which is the hydrophilic fouling substance 105 floating in the air, is a fine particle having a size of several μm to several tens of μm. Moreover, the dust which is also the hydrophilic fouling substance 105 is much larger than sand dust, and has a size of 0.1 mm to 5 mm. In order for such a hydrophilic fouling substance 105 to adhere to the hydrophilic portion on the surface of the article by the above-described action, the hydrophilic fouling substance 105 and the hydrophilic portion on the article surface can be sufficiently adhered (can be contacted). ) Only hydrophilic area must be present.

  However, since the coating film 103 formed by the coating composition 200 of this embodiment is dispersed with the fluororesin particles 102 exhibiting hydrophobicity moderately dispersed in the silica film 104 exhibiting hydrophilicity, In addition, there is almost no surface of the silica film 104 having a continuous area enough for the hydrophilic fouling substance 105 to stably adhere. The hydrophilic fouling substance 105 adhering onto the coating film 103 is caused by the hydrophobicity of the surface of the fluororesin particles 102 protruding (exposed) from the silica film 104 or the physical properties of the protruding fluororesin particles 102. Due to the inhibition, the surface of the silica film 104 cannot be sufficiently adhered. For this reason, the hydrophilic fouling substance 105 is easily detached and does not adhere to the coating film 103.

  The silica film 104 is composed of silica fine particles 101 (the role of the binder is also played by the silica component of the silica fine particles 101), and is a porous film having fine voids between the silica fine particles 101, so that the density is high. Even if the hydrophilic fouling substance 105 is small, the intermolecular force is small and it is difficult to fix the hydrophilic fouling substance 105.

  Furthermore, since the porous silica film 104 has fine voids between the silica fine particles 101, even if liquid crosslinking is caused by water or the like, the water between the hydrophilic fouling substance 105 and the silica film 104 surface, Since it is removed through fine voids in the silica film 104 and liquid cross-linking is lost, the hydrophilic fouling substance 105 is not fixed by liquid cross-linking.

  As described above, the coating film 103 formed by the coating composition 200 exhibits excellent antifouling performance against the hydrophilic fouling substance 105.

  On the other hand, if there is an interval between the scattered fluororesin particles 102 and there is a continuous silica film 104 without being blocked by the fluororesin particles 102, the hygroscopicity on the surface of the silica film 104 is improved. Since the electric charge charged to 103 is likely to leak, there is an advantage that the charging of the surface of the coating film 103 can be efficiently suppressed. When the surface of the article is charged, fine suspended particles, which are fouling substances in the air, regardless of hydrophilicity or hydrophobicity, are attracted by electrostatic attraction and easily adhere to the article surface.

  The coating film 103 has continuity that can suppress charging, that is, the fluororesin particles 102 are scattered at appropriate intervals such that the silica film 104 has a continuous area that can leak charges. It has the effect of preventing the attachment of airborne particles (fouling substances). By coating the surface of the article with the coating composition 200 and forming the coating film 103 on the surface, dirt derived from static electricity can be prevented.

  The amount of the silica fine particles 101 in the coating composition 200 is preferably 17:83 or more in terms of the weight ratio of the silica fine particles 101 and the fluororesin particles 102.

  When the amount of the silica fine particles 101 in the coating composition 200 is less than 10:90 in terms of the weight ratio of the silica fine particles 101 and the fluororesin particles 102, the interval at which the fluororesin particles 102 are scattered in the silica film 104 becomes narrow. It is difficult to obtain the effect of suppressing charging by the continuous silica film 104 as described above, and thereby the effect of preventing dirt derived from static electricity, and although the film can be constructed, the antifouling performance is somewhat inferior.

  The hydrophobic fouling substance 106, which is another fouling substance, is oily smoke, carbon, cigarette dust, etc., and those that cause fouling are those floating in the air as fine particles. The particle diameter is 5 μm or less, and most are 0.1 to 0.3 μm, which is smaller than the hydrophilic fouling substance 105.

  Since the hydrophobic fouling substance 106 has a hydrophilic group or adsorbed moisture on the surface portion that exhibits hydrophilicity, it is difficult to adhere to the surface portion that exhibits hydrophilicity, and is easily adhered to the surface portion that exhibits hydrophobicity. The reason why such a hydrophobic fouling substance 106 adheres to the surface of the article is due to intermolecular forces generated by the hydrophobic fouling substance 106 coming into close contact with the surface portion exhibiting hydrophobicity.

  In the coating composition 200, the hydrophobic resin is the fluororesin particle 102 having an average particle diameter of 50 to 500 nm as described above. In the coating film 103 formed on the article surface, the fluororesin particles 102 may be larger than a single particle size due to deformation or coalescence. The fluororesin particle 102 is equal to or smaller than the size of the hydrophobic fouling substance 106 that causes contamination, and the hydrophobic fouling substance 106 is sufficiently adhered to the fluororesin particle 102 having a hydrophobic surface portion. There is often no area that can be created.

  In such a case, intermolecular forces that are fixed to each other do not act, and the hydrophobic fouling substance 106 is difficult to fix to the fluororesin particles 102 exhibiting hydrophobicity. Naturally, the hydrophobic fouling substance 106 does not adhere to the hydrophilic silica film 104, so that the coating film 103 exhibits high antifouling performance against the hydrophobic fouling substance 106.

  Since the size (particle size) of the fluororesin particles 102 is equal to or smaller than the size of the hydrophobic fouling substance 106, the hydrophobic fouling substance 106 is sufficient for the fluororesin particles 102 of the coating film 103. The hydrophobic fouling substance 106 partially adheres to the fluororesin particles 102 and partially adheres due to the action of the intermolecular force. there is a possibility. Further, the hydrophobic fouling substance 106 may be smaller than the fluororesin particles 102, and it is possible that the fluororesin particles 102 have an area where they can sufficiently adhere to each other.

  However, in addition to the above, the coating film 103 has another function of preventing the hydrophobic fouling substance 106 from adhering to the fluororesin particles 102. Such partial adhesion, adhering of the small hydrophobic fouling substance 106 is possible. Even make it difficult to happen. The operation will be described below.

  The fluororesin particles 102 of the coating composition 200 depend on the surfactant added during polymerization of the fluororesin, in a dispersion in water, and in a coating solution mixed with the dispersion of silica fine particles 101. The surface is in a hydrophilic state.

  When the coating film 103 is dried, the surfactant is peeled off and the surface of the fluororesin particles 102 becomes hydrophobic, but the silica fine particles 101 coexist in the coating solution. Therefore, the silica fine particles 101 having a smaller particle diameter than the fluororesin particles 102 are sparsely attached to the surface of the fluororesin particles 102 of the coating film 103 formed after drying.

  Thus, since the silica fine particles 101 having hydrophilic groups (showing hydrophilicity) are scattered and attached to the surface of the fluororesin particles 102, the surface of the fluororesin particles 102 is partially covered with the hydrophobic fouling substance 106. Thus, the hydrophobic fouling substance 106 smaller than the fluororesin particles 102 is less likely to adhere.

  By partially introducing a hydrophilic group onto the surface of the fluororesin particle 102, an effect of suppressing the adhesion between the fluororesin particle 102 and the hydrophobic fouling substance 106 can be obtained. Even if the hydrophobic fouling substance 106 adheres to the surface of the fluororesin particles 102, the silica fine particles 101 are scattered and adhered, so the adhesion is unstable and can be easily detached.

  On the other hand, even on the surface of the fluororesin particles 102 on which the silica fine particles 101 are sparsely adhered, the hydrophilic fouling substance 105 which is much larger than the size of the silica fine particles 101 is sufficient. Therefore, the hydrophilic fouling substance 105 does not adhere to the surface of the fluororesin particles 102.

  Further, although the fluororesin particles 102 have a flexible surface, the surface of the fluororesin particles 102 is hardened by the silica fine particles 101 adhering sparsely in this manner, and the hydrophobic fouling substances 106 are adhered to each other. The effect which becomes difficult to do is also acquired.

  In addition, the fluororesin itself has a very low surface energy and a low coefficient of friction, as is well known in the fluororesin coating, so that it not only exhibits hydrophobicity but also has oil repellency. Compared to a hydrophobic resin, the hydrophobic fouling substance 106 is less likely to stick. This is one of the effects that the hydrophobic fouling substance 106 does not adhere to the fluororesin particles 102.

  As described above, the coating film 103 formed by the coating composition 200 also exhibits excellent antifouling performance against the hydrophobic fouling substance 106.

  By changing the weight ratio between the silica fine particles 101 and the fluororesin particles 102 in the coating composition 200 (weight of the silica fine particles 101: weight of the fluororesin particles 102), it can be arbitrarily adjusted from hydrophilic to hydrophobic. . A coating film 103 in which a hydrophilic region formed by the silica fine particles 101 (silica film 104) and a hydrophobic region formed by the fluororesin particles 102 are mixed in a well-balanced manner is obtained by drying at room temperature. If a large amount of silica fine particles 101 is added, it becomes strong against hydrophobic dirt, and if a large amount of fluororesin particles 102 is added, it becomes strong against hydrophilic dirt. Further, since the density is as low as about 1/10 of that of metal, the intermolecular force with the dirt particles can be reduced to suppress the sticking over time, and it is easy to peel off even with wind.

  However, even when the pure silica film 104 is formed using only the silica fine particles 101, the antifouling effect is considerably limited, but the effect of keeping away hydrophobic particles such as oil smoke and the electrostatic force and intermolecular force of the surface. As compared with the case where no coating is applied, the stain resistance is improved.

  In addition, when the thickness of the silica film 104 is larger (thicker) than the particle diameter of the fluororesin particles 102, the silica film 104 exhibiting hydrophilicity is widely exposed as the surface of the coating film 103. Antifouling performance against the fouling substance 105 is inferior.

  Further, the dispersion of the fluororesin particles 102 in the silica film 104 is inhibited, the fluororesin particles 102 are separated from the silica film 104 and deposited on the surface of the silica film 104, and the fluororesin particles 102 are united to form a lump. Therefore, it is possible that the hydrophilicity locally deteriorates at that portion or the hydrophobic fouling substance 106 is fixed. Therefore, as described above, the thickness of the silica film 104 is smaller (thinner) than the average particle diameter of the fluororesin particles 102, and the fluororesin particles 102 are appropriately dispersed in the silica film 104. The resin particles 102 can be partially exposed from the silica film 104 instead of the whole.

  As the fluororesin particles 102 in the coating composition 200, PTFE (polytetrafluoroethylene), FEP (tetrafluoroethylene / hexafluoropropylene copolymer), PFA (tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer), ETFE (ethylene / tetrafluoroethylene copolymer), ECTFE (ethylene / chlorotrifluoroethylene copolymer), PVDF (polyvinylidene fluoride), PCTFE (polychlorotrifluoroethylene), PVF (polyvinyl fluoride), etc. These copolymers or mixtures, or those obtained by mixing these with other resins can be used.

  The fluororesin particles 102 need to be in the state of a dispersion dispersed in water before the coating composition 200 is manufactured. The dispersing method can be performed by using fluororesin particles 102 polymerized by suspension polymerization or emulsion polymerization and using a surfactant. In the state dispersed in water, the surface of the fluororesin particles 102 is in a state of low hydrophobicity, but the surface is hydrophobic in the state of being dried to form a solid (coating film 103). What should I do? As the fluororesin used, PTFE and FEP are particularly excellent in stability that they do not aggregate in the dispersion or coating solution, and also have a high hydrophobicity when dried to form the coating film 103. To preferred.

  As described above, since the coating film 103 formed on the surface of the article by the coating composition 200 has both properties, both the hydrophilic fouling substance 105 and the hydrophobic fouling substance 106 are not fixed and adhered. However, it can be easily detached, so that excellent antifouling performance and releasability can be exhibited and contamination of the coated filter surface can be prevented. Also in examples (experimental results) described later, it is proved that the antifouling performance of the coating composition 200 according to this embodiment is excellent.

  The manufacturing method of the coating composition 200 of this embodiment is not particularly limited, but can be easily manufactured by mixing the dispersion of the silica fine particles 101 and the dispersion of the fluororesin particles 102. Can do. Here, as the dispersion liquid of the silica fine particles 101, one in which the silica fine particles 101 having an average particle diameter of 15 nm or less are dispersed in water, for example, commercially available colloidal silica can be used. In the dispersion of the silica fine particles 101, the volume ratio of the silica fine particles 101 in the dispersion is preferably 20% or less. This is because if the volume ratio exceeds 20%, the stability of the dispersion liquid may be deteriorated, for example, the silica fine particles 101 may be aggregated.

  Further, as the dispersion liquid of the fluororesin particles 102, a dispersion in which the fluororesin particles 102 having an average particle diameter of 500 nm or less are dispersed in water, for example, PTFE dispersion can be used. In order to uniformly disperse the hydrophobic fluororesin particles 102 in the coating composition 200, a surfactant may be added. In either dispersion, the polar solvent is not limited to water.

  The water used in each dispersion is not particularly limited, but ionic properties such as calcium ions and magnesium ions are used to disperse and stabilize the silica fine particles 101 and the fluororesin particles 102 without agglomeration. The thing with few impurities is good. The divalent or higher ionic impurity is desirably 200 ppm or less, and more desirably 50 ppm or less. If divalent or higher ionic impurities increase, the silica fine particles 101 and the fluororesin particles 102 may aggregate and precipitate, or the strength and transparency of the coating film 103 to be formed may decrease.

  Since this coating composition 200 does not contain an organic solvent, it is safe and environmentally friendly. Moreover, since it can manufacture only by mixing the dispersion liquid marketed as mentioned above, there exists an advantage which can be manufactured easily at low cost.

  However, the coating composition 200 can ensure the stability of the hydrophobic fluororesin particles 102, improve the adhesion of the coating film 103 to be formed, and adjust the hydrophilicity of the coating film 103 according to the material of the article to be coated. From the viewpoint of achieving this, a surfactant or an organic solvent may be added. In addition, a coupling agent or a silane compound may be added to the coating composition 200 for the purpose of improving the adhesion, transparency, and strength of the coating film 103 to be formed, and adjusting the hydrophilicity of the coating film 103. .

  Here, examples of the surfactant that can be used in the coating composition 200 include various anionic or nonionic surfactants. Among such surfactants, polyoxypropylene-polyoxyethylene block polymers, polycarboxylic acid type anionic surfactants and the like are preferable because they have low foaming properties and are easy to use.

  Examples of the organic solvent that can be used in the coating composition 200 include various alcohol-based, glycol-based, ester-based, and ether-based solvents.

  Further, examples of the coupling agent that can be used for the coating composition 200 include amino-based compounds such as 3- (2-aminoethyl) aminopropyltrimethoxysilane, and epoxy-based compounds such as 3-glycidoxypropyltrimethoxysilane, 3 -Methacryloxy type such as methacryloxypropylmethyldimethoxysilane, mercapto type, sulfide type, vinyl type, ureido type and the like.

  Examples of the silane compound usable in the coating composition 200 include halogen-containing materials such as trifluoropropyltrimethoxysilane and methyltrichlorosilane, alkyl group-containing materials such as dimethyldimethoxysilane and methyltrimethoxysilane, 1,1 , 1,3,3,3-hexamethyldisilazane and the like, and oligomers such as methylmethoxysiloxane.

  The content of the above additives is not particularly limited as long as it does not impair the antifouling performance, the contact angle with water, and the adhesion of the coating composition 200, and depends on the selected additive. May be adjusted accordingly.

  The method of coating the surface of the article with the coating composition 200 of this embodiment is not particularly limited, and can be performed using a conventionally known method, but the coating composition 200 is coated. It is desirable to remove the excess coating composition 200 with an air flow after application to the surface of the article by dipping, spraying, or spraying. If the excess coating composition 200 stays on the surface of the article, the coating film 103 formed on the surface of the article becomes thick and may become cloudy and impair the color tone and texture of the resin 107 to be coated.

  By using the air flow, the effect of promoting drying is also obtained, and there is an advantage that a good coating film 103 in which the fluororesin particles 102 are appropriately scattered in the silica film 104 can be obtained. In particular, when it is desired to obtain hydrophilicity, it is preferable to give a high wind speed of 10 to 25 m / s or more. However, when the base is a resin with high water repellency, the coating liquid will fly off in a strong air current, and therefore the coating may be fixed as appropriate by a weak air current or standing drying.

  In addition, as will be described later, in order to prevent dew dripping, it is necessary to adjust the contact angle with water droplets to about 50 to 90 °, and in order to adjust the contact angle, many fluororesin particles 102 are exposed on the surface. In order to prevent the fluororesin particles 102 from being hidden by the silica fine particles 101, it is preferable to dry them at a relatively low wind speed of about 1 to 10 m / s. Rich in expression.

  Up to now, the antifouling performance of the coating composition 200 in which the fluororesin particles 102 are dispersed based on the silica fine particle 101 film has been described. However, the antifouling property when applied to resin parts that are prone to mold is described below. A mold prevention method for preventing damage will be described.

  FIGS. 6 and 7 are diagrams showing the first embodiment, and FIG. 6 is a conceptual diagram showing a cross section in a state where a coating composition 200 containing a fungicide is coated on the resin surface and a coating film 103 is formed. FIG. 7 is a conceptual view of the top surface of the coating film 103 of FIG.

  When a mold-proofing agent is kneaded into a resin as in the prior art, many molds are buried in the resin and do not come out on the surface at the time of molding, so the contact ratio with mold is low and the effect is poor. In addition, when the fungicide is buried in the lower layer rather than the surface of the coat layer, the fungicide is difficult to achieve unless the amount of the fungicide eluted is large, but the sustainability is poor.

  Further, when the anti-fungal agent 120 having a large particle diameter is arranged as in the conventional case, even if the contact ratio with the mold is high, the adhesion area with the scattered dirt increases, and the anti-fungal agent is contaminated. End up.

  Therefore, in the present embodiment, as shown in FIGS. 6 and 7, the fungicide 120 is atomized to 10 μm or less, then the fungicide 120 is dispersed in an aqueous medium, and the silica fine particles 101 and the fluororesin particles 102 are dispersed. The final antifungal agent 120 is mixed with an aqueous medium diluted with pure water having a combined solid content of 0.1 to 5.0% by weight, preferably 0.3 to 2.5% by weight. A coating solution (aqueous medium) was prepared, applied to the coating resin 107, and fixed by blow drying. If the solid concentration is less than 0.1% by weight, the antifouling effect is lost, and if it is more than 5.0% by weight, the particles are not well dispersed and cracks occur.

  As a result, it is possible to form the coating film 103 in which the fluororesin particles 102 are dispersed in the film in which the silica fine particles 101 are continuously connected to the surface of the underlying resin 107 to be coated, and the fungicide 120 is also dispersed. .

  As a coating method, a dip method in which the resin to be coated 107 is immersed in a coating solution, a spray method in which the coating solution is sprayed by applying pressure from a nozzle, a wiping method in which the coating solution is wiped with a non-woven fabric containing the coating solution, and the like are practical.

  Since the fungicide 120 is atomized to 10 μm or less, there is an effect that it is widely dispersed throughout the coating film 103 without remaining at one place on the surface by blow drying. More preferably, if the particles are atomized to 2.0 μm or less, the dispersion effect is remarkable without aggregation.

  FIG. 8 shows the first embodiment, and is a diagram showing the particle size distribution and frequency when thiabendazole (TBZ), which is a general-purpose antifungal agent, is used as an example of an antifungal agent.

  As a method of atomization, there is a method of crushing with a mixer device, but there is a method in which the particle size is reduced with beads through an antifungal agent in a device in which glass beads are spread. In addition, the particle size distribution and the average particle size are more effectively reduced by using a method of crushing particles by shearing force through a linear flow path or a method of crushing particles by colliding with each other at high pressure. Can be atomized. In addition, by passing the apparatus several times, not only once but several tens or hundreds of times, finer atomization can be achieved and a remarkable effect can be obtained.

  In FIG. 8, the average particle size was around 10 μm at first, but the average particle size becomes 5 μm by processing three times, and the average particle size is reduced to 1.0 μm or less by processing 200 times. I was able to. Of course, zinc pyrithione (ZPT) and other particulate fungicides are also atomized in the same way, so that they can be uniformly dispersed without causing damage to the effect of the antifouling coating due to trapping caused by the particles. Can increase the probability.

  Various kinds of dirt such as dust, dust, oil smoke, and cigarette dust are present on the surfaces of various articles used indoors and outdoors. The size of each fouling scattered material is: synthetic fiber 0.1 mm (100 μm) to 5 mm, natural fiber 0.1 mm (100 μm) to 5 mm, dandruff and plaque 10 to 100 μm, starch and flour 10 to 50 μm, foundation 1 to 50 μm, The pollen is 10 to 30 μm, dust / yellow sand / diesel exhaust gas particles 1 to 10 μm, mold spores 3 to 10 μm, microbial dead bodies and mites 1 to 100 μm.

  In the present embodiment, the resin parts are coated to prevent diversity stains. However, the microscopic unevenness is formed only on the outermost surface by the continuous film in which the silica fine particles 101 are connected and the fluororesin particles 102. Although it is a macro coating, it is a smooth coating that does not get dirty. This is because the silica fine particles 101 and the fluororesin particles 102 are appropriately dispersed using nano-level particles.

  When adding the fungicide 120 here, it is useful to make the particles smaller in order not to impair the antifouling effect. As a guide to atomization, if the size of the added particles is 10 μm or less, the size of indoor pollutants such as synthetic fibers, natural fibers, dandruff and plaque, starch and wheat flour, pollen, microbial dead bodies, etc. is almost the range. However, since the particle diameter is small, the risk of these stains is greatly reduced by the irregularities created by the particles.

  If the average particle size is 10 μm or less, it can be judged that the surface to which these stains can adhere is very small because it is small. Furthermore, if the particle size is preferably set to 2.0 μm or less, small dirt such as dust, yellow sand, diesel exhaust gas particles and mold spores will not be caught by this fungicide, and the particles should be made as small as possible. . If the average particle size is 2.0 μm or less, the fouling effect due to the antifungal agent can be almost eliminated.

  Of course, the anti-fungal agent 120 having an average particle size of 10 μm or less before the treatment is problematic because it is evenly dispersed and less contaminated even if it is used untreated to reduce processing costs. Absent. Even in that case, the finer atomization treatment is preferable from the viewpoint of dispersibility and prevention of contamination. Even when the primary particle size is smaller than 10 μm, the secondary particle size is often larger than 10 μm due to aggregation, and can be returned to the primary particle size level again by making fine particles. It can be further refined by selecting a method.

  Up to this point, the description has been limited to the fungicide 120, but of course, in places where there are many fungi such as pink yeast, an antibacterial material having an antibacterial action may be used, and the smaller the particle size, the same. Good. Of course, the antifungal agent 120 and the antibacterial agent may be mixed and used, but the particles should be smaller.

  So far, the antifouling property of the coating composition 200 in which the fluororesin particles 102 are dispersed based on the silica fine particle 101 film and the method of adding the antifungal agent have been described. The suppression of dripping in the case will be described.

  FIG. 9 shows the first embodiment and is a schematic diagram for explaining the contact angle θ of the water droplet 50 attached to the resin surface.

  Here, the contact angle θ is an angle formed by a tangent line TL at a portion of the water droplet 50 attached to the resin surface in contact with the resin surface and the resin surface. High hydrophilicity means that the attached water droplet 50 tends to spread, that is, the smaller the contact angle θ (closer to 0 degree), the higher the hydrophilicity or the better the hydrophilicity.

  In FIG. 9, the water drop 50 shown in (b) has a smaller contact angle θ than the water drop 50 shown in (a). Conversely, high water repellency means that the adhesion area of the water droplets 50 that adhere is small, that is, the larger the contact angle θ (closer to 180 degrees), the higher the water repellency or the better the water repellency. become.

  In order to hold water droplets on the resin, an appropriate contact angle θ that is intermediate between hydrophilicity and water repellency is preferable. If the hydrophilicity is too high or the water repellency is too high, the water moves at an increased speed. As a clear guide, if the contact angle θ is a hydrophilic surface of 30 degrees or less, the water droplets immediately move in the direction of gravity while spreading.

  If the contact angle θ is a water-repellent surface having a contact angle θ of 100 to 120 degrees or more, the water droplet rolls on the resin while maintaining the shape of the water droplet to some extent. When the contact angle θ is about 150 degrees, the water droplets slide down while splashing on the resin surface.

  For the casing part 15, the left and right vanes 13, and the upper and lower flaps 17 that are to be coated provided in the air conditioner 100, general-purpose organic resins such as PS (polystyrene), ABS (acrylonitrile butadiene styrene), and PP (polypropylene) are used. There are many cases. The contact angle θ of these resins is at least 50 degrees or more, generally about 80 to 90 degrees, and is a slightly water repellent surface. Accordingly, since the contact angle θ is moderate, the attached water droplet 50 is difficult to fall, but when dirt such as dust or dust adheres due to long-term use, the surface gradually becomes hydrophilic, and the contact angle θ is 40 It will be 30 degrees or less which is a sufficient hydrophilic level in general. Then, dew propagates while spreading the surface in the direction of gravity and moves on the surface of the resin part. In the worst case, water drops fall into the user's room from the blower fan 20 and the casing unit 15 provided in the indoor air conditioner 100. On the contrary, if water repellent treatment is performed, dew rolls off the surface, which is not good.

  Even if there is no problem in the initial stage, due to the adhesion of dirt due to long-term use, even if the surface is modified and the contact angle becomes 40 degrees or less, it often leads to a problem of dripping. Therefore, as a measure for preventing dew dripping, the contact angle θ with the water droplets should be maintained between 50 and 90 degrees. More preferably, the contact angle θ with the water droplet is set to about 60 to 80 degrees. Further, the contact angle with the water droplets can be maintained by preventing the adhesion of dirt over a long period of time by the antifouling coating. Therefore, there are few dripping problems compared with the conventional resin that is not subjected to the coating composition 200 and becomes hydrophilic due to aging stains.

  Actually, an experiment was performed using a microsyringe. In the experiment, a dripping amount was calculated in which water drops were dripped onto the PS surface and no dew dripping occurred. A sample that did not cause dripping even when 5 μl was dropped was used as a pass criterion. When the contact angle θ with the water droplet was 35 degrees or less, the water droplet could not be retained, but when it was 50 degrees or more, the water droplet could be retained.

  The weight ratio of silica fine particles 101 to fluororesin particles 102 in coating composition 200 (weight of silica fine particles 101: weight of fluororesin particles 102) is set to 5:95 to 35:65, and the drying speed in the coating process is set. By appropriately adjusting, the contact angle θ with the water droplet can be set between 50 and 90 degrees.

  When the weight ratio between the silica fine particles 101 and the fluororesin particles 102 is smaller than 5:95, the aggregation of the fluororesin particles 102 becomes excessive, or the area covered with the fluororesin particles 102 increases, thereby preventing charging. The effect cannot be obtained, and the antifouling property against hydrophobic soil is remarkably lowered.

  When the weight ratio between the silica fine particles 101 and the fluororesin particles 102 is larger than 35:65, the proportion of the silica fine particles 101 increases and the balance as antifouling performance is improved, but the silica fine particles 101 are hydrophilic. The contact angle θ with the water droplet cannot be made to be 50 degrees or more. That is, even if the antifouling property is good, it becomes a macroscopically hydrophilic film and causes drooling, which is not suitable as a coating for resin to be applied to a site where the dripping is a concern.

  So far, the antifouling property of the coating composition 200 in which the fluororesin particles 102 are dispersed based on the silica fine particle 101 film, the method of adding the antifungal agent, and the suppression of the dripping have been described. Adhesiveness with will be described.

  As described above, the casing 15, the left and right vanes 13, and the upper and lower flaps 17 that are the coating objects provided in the air conditioner 100 are general-purpose organic resins such as PS (polystyrene), ABS (acrylonitrile butadiene styrene), and PP (polypropylene). Is used. The blower fan 20 is made of ASG (acrylonitrile styrene containing glass).

  However, while the coating composition 200 that can achieve both hydrophilicity and antifouling property is a safe coating that does not use an organic solvent or the like, since it is an inorganic structure, it has good adhesion to metal materials and the like. There is a problem of poor adhesion to organic resins. In addition, since these resins have a water repellent surface, the aqueous coating itself does not adhere uniformly. Therefore, even if a water-based inorganic dispersion coating solution is applied onto the organic resin that is the part to be coated, the film does not partially adhere to the organic resin, or the film naturally peels off after long-term use. Moreover, even when rubbed by wiping and cleaning, it becomes easy to peel off.

  Conventionally, various methods have been taken to improve the adhesion of the coating. For example, a pretreatment such as corona treatment or UV treatment is performed on the article surface in advance. As a result, the surface of the resin is modified and adhesion is improved even with a coating material having poor compatibility.

  There is also a two-step application method in which a primer layer, which is an undercoat adhesive material, is applied to the surface of the resin (coating resin 107) in advance on the resin to be coated 107, and the coating of the present embodiment is applied thereon. As the primer layer, for example, a polyolefin layer or the like is suitable, and improved adhesion and improved flatness can be obtained.

  However, when performing these corona treatment, UV treatment, and primer two-layer treatment, there is a problem that large-scale equipment is required, treatment time is required, and costs increase. Not suitable for products that require Therefore, in this embodiment, as a simplest and low cost method suitable for mass production, a small amount of radical generator 111 or peroxide 112 is added to the coating solution.

  Here, the radical generating material 111 is generally used for radical polymerization for connecting molecules, and is defined as having a decomposition action by heat of about 60 ° C. or more. Radical polymerization is a type of polymerization reaction in polymer chemistry, and is a reaction in which a polymer chain extends with a radical as a reaction center. Examples of the radical generating material 111 include BPO (benzoyl peroxide; oil-soluble) that thermally decomposes, AIBN (azobisisobutyronitrile), AVCA (4,4-Azobis (4-cyanovaric Acid)), and the like.

For example, as an example of radical polymerization, there is polyethylene production by polymerization of ethylene. The reaction to generate free radicals as radical polymerization initiators decomposes BPO and AIBN by light or heating, and generates radicals by cutting off oxygen or breaking double bonds as shown below. Let
RO-OR → 2RO ・
R2 (NC) CN = NC (CN) R2 → 2 R2 (NC) C · + N2

  In addition, the peroxide 112 is an abbreviation or another name for the following substances, and is defined as having water solubility and having a self-decomposing action at room temperature. Usually, it is used as an oxidizing agent or a bleaching agent, but is not used in coating applications. Inorganic compounds mainly have a structure in which the inorganic peroxide 112, which has a chemical formula of a metal salt of hydrogen peroxide, or a hydroxy group (—OH) of an oxo acid is replaced with a hydroperoxide group (—O—OH). The substance it has is called peroxide 112. In addition, organic compounds mainly contain a compound having a peroxide structure (—O—O—) as a functional group or a compound having a percarboxylic acid structure (—C (═O) —O—O—) as a functional group. Called oxide 112. Hydrogen peroxide is the most common.

  The original radical generating material 111 is a material for polymerizing a single molecule, and the peroxide 112 is a material used as an oxidizing agent or a bleaching agent. By selecting the peroxide 112, a general-purpose organic resin such as PS (polystyrene), PP (polypropylene), ABS (acrylonitrile butadiene styrene), ASG (acrylonitrile styrene containing glass), silica fine particle 101 film and fluorine resin particle 102 are used. It came to discover that there exists an effect which improves adhesiveness with the inorganic type coating composition 200 formed using the dispersion liquid of this.

  FIG. 10 is a diagram showing the first embodiment, and is a conceptual diagram showing a cross section in a state where the coating composition 200 to which the radical generating material 111 or the peroxide 112 is added is coated on the resin surface and the coating film 103 is formed. is there.

  As shown in FIG. 10, the radical generating material 111 or the peroxide 112 is dispersed in the coating film 103. By adding a small amount of the radical generating material 111 or the peroxide 112 to the coating solution, the coating solution becomes difficult to be repelled even on a highly water-repellent resin and is easily applied.

  Further, as the radical generating material 111 or the peroxide 112 is decomposed by heat or self-decomposed with time, a fluororesin dispersion (also referred to as a dispersion) is formed particularly near the interface between the coating resin 107 and the silica film 104 as a base. The monomer component and the surfactant contained in (3) serve as a reaction starting point, exerting a change in the aggregated form of silica and an adhesion effect between the resin to be coated 107 and the silica film 104, thereby improving the adhesion. These cannot be established without either the resin dispersion or the reactive material (radical generator 111 or peroxide 112).

When BPO, which is a hardly water-soluble thermal radical, was added, the adhesion with the resin was improved. Specifically, even if the air wiping with a pressure of 80 gf / cm ² is performed 500 times or more, the film remains without being peeled off, and the stain reduction effect is 50% or more compared with the case where the coating composition 200 is not applied. Was holding. Even if it is left at room temperature, there is an effect of improving adhesion, but since it is a thermal radical, the effect is further enhanced by applying heat of 60 degrees or more. The addition amount of BPO was suitable as about 0.01% to 1% of the entire coating solution, and the effect was confirmed.

  As another method, adhesion is improved when ammonium persulfate (APS), sodium persulfate, and hydrogen peroxide, which are water-soluble peroxides 112, are added. Since it is a peroxide 112, it exhibits an effect of improving adhesion by self-decomposition even when left at room temperature, but since decomposition occurs efficiently, the effect is further enhanced by applying heat at 60 ° C. The addition amount of the peroxide 112 was suitable as about 0.01% to 1% of the entire coating solution, and the effect was confirmed. The radical generating material 111 and the peroxide 112 are decomposed and lost with addition, heat and time, and have an effect of separating / modifying by reacting with the surroundings.

  Use of radical generator 111 or peroxide 112 eliminates the need for large-scale equipment such as corona treatment, UV treatment, and primer two-layer treatment (adhesive layer), and requires multiple coating steps other than single-layer coating. Therefore, it is possible to easily apply the inorganic coating composition 200 on the organic resin, which is inexpensive and has high adhesion and is difficult to peel off.

  Further, when the radical material is added, as in the case of the antifungal agent, the atomization treatment is performed so that the dirt is caught and the antifouling property is not impaired.

  FIG. 11 is a diagram showing the first embodiment and is a diagram showing the particle size distribution and the frequency when BPO (benzoyl peroxide; oil-soluble) is atomized as a radical material. BPO has a wide particle size distribution in the range of 10 to 100 μm, but the average particle size is reduced to 10 μm or less by performing the atomization process three times, and the antifouling property is not impaired. Moreover, when it is performed 200 times or more, the average particle diameter becomes about 2.0 μm, and the antifouling property is not impaired at all.

  In addition, the application example to the ventilation fan 20, the casing part 15, the left-right vane 13, the upper-and-lower flaps 17, and the nozzle 18 which coat | covered the surface with the coating film 103 by the coating composition 200 of this embodiment as the air conditioner 100 is described. However, the coating composition 200 of this embodiment can coat the surfaces of various articles without being limited thereto.

  The applicable article is not particularly limited, but is excellent in antifouling performance. Therefore, it can be used in various places such as dust, oil smoke and cigarette dust (hydrophilic) Examples include various articles to which the fouling substance 105 and the hydrophobic fouling substance 106) may adhere. Moreover, since it is also excellent in antifungal properties, it is suitable for articles exposed to high humidity, articles used in a high humidity environment, and articles through which steam passes.

Specific examples of the article to be applied include those shown below.
(1) Air conditioner indoor unit housing (outer) surface;
(2) Operation button surface of air conditioner remote control;
(3) Air conditioner remote control casing surface;
(4) Ventilation fans, casings and casings of ventilation fans that suck in steam and oil smoke;
(5) The outline of a hand dryer that blows water off the hands;
(6) Disc type humidifier that scoops up the stored water with a flat plate;
(7) Toilet toilet outline;
(8) Bathroom and washroom;
(9) Building outer walls and roofs.

  Further, PS, PP, ABS, and ASG are taken as examples of the base resin, and BPO is given as the radical generating material 111 to be added, and ammonium persulfate (APS), sodium persulfate, and hydrogen peroxide are given as examples of the peroxide 112. However, the present invention is not limited to this, and the means for adding the radical generating material 111 or the peroxide 112 is useful for improving long-term adhesion when an inorganic coating is applied on a resin composed of various organic materials. It is. The antifouling property can be obtained by applying the coating of the present embodiment simultaneously with the adhesion.

  From here, the process of forming the coating composition 200 on the blower fan 20 will be specifically described. The blower fan 20 of the present embodiment is a cross flow fan applied to a wall-mounted air conditioner. However, any propeller fan, sirocco fan, turbo fan, propeller fan, or the like that sucks or pushes in air by rotation may be used.

  The blower fan 20 of the present embodiment is a blower fan 20 that is provided in the downstream of the heat exchanger 30 that requires mold prevention and is exposed to high-humidity air, but is normally used in a high-humidity environment. Even an unfamiliar fan is suitable for application because it generates mold when exposed to steam or an air environment of high humidity.

  FIG. 12 shows the first embodiment and is a cross-sectional view showing the unused normal blowing fan 20. The blower fan 20 is a cross flow fan. The cross flow fan includes a plurality of blades 21 (blades) in the circumferential direction, and the blower fan 20 rotates around the central axis in the rotation direction 25 so that the blades 21 take in and send out the wind.

  The blade 21 has an arc shape and includes a concave surface 22 and a convex surface 23. Further, a blade tip 24 is provided in the centrifugal direction of the blade 21, and an inner peripheral portion 27 is provided in the inner peripheral direction.

  In general, the surface of the blower fan 20 is weakly hydrophobic, and water condensed on the blower fan 20 is held as water droplets. The retained water droplets often collect at the blade tip 24 due to centrifugal force as the blower fan 20 rotates. Further, 70% of the suspended solids present in the home are fine dust particles, but cannot be captured by the filter 40 provided on the front surface of the heat exchanger 30. Therefore, the dust that has passed through the filter 40 collides with and adheres to the rotated blower fan 20. There is a bias in the dust adhesion position, and there are particularly many blade tip portions 24 with high wind speed and strong impact force. Therefore, the blade tip 24 accumulates dust and dust and also collects water droplets by centrifugal force. Therefore, the blade tip 24 is highly humid and highly nutritious, and is the most easily breeding part for mold. Further, not only the blade tip 24 but also the concave surface 22 has a larger wind collision force than the convex surface 23, so that dirt easily adheres and accumulates and moisture is easily retained.

  FIG. 13 shows the first embodiment, and is a cross-sectional view showing the blower fan 20 with mold. In the blower fan 20 that performs air conditioning, a case in which a foreign substance development phenomenon is frequently observed from the concave surface 22 of the blower fan 20 to the blade tip portion 24 occurs frequently. This foreign matter is a mold deposit 26 having roots in dirt. In a bad environment, the number of mold spores per 1 cc of the part attached to the blower fan 20 is 40 times that of the heat exchanger 30, and when mold and mycelium deposits develop at the blade tip 24, the wind passage is blocked. In a unit that has been used for 10 years, the air volume is reduced by about 30% compared to the initial stage, and the electricity cost is reduced by about 10%. Further, the odor index generated by the blower fan 20 is the highest even when compared with many parts, and is a major cause of the off-flavor and allergen substance scattering in the air conditioner 100.

In the coating process, the following processes are sequentially performed.
(1) Preparation step of coating liquid (aqueous medium);
(2) An application step of applying an aqueous medium;
(3) A drying step for fixing the coating composition.

  In the preparation step, the above-mentioned surfactant contains hydrophilic inorganic fine particles for imparting antifouling properties, one or both of hydrophobic resin particles, and finely divided antifungal or antibacterial particles. Mix together.

The application process serves to attach the aqueous medium to the resin member. As an example of the coating process, the following methods can be considered.
(1) A dipping method in which the entire blower fan 20 is immersed together with its members;
(2) Dipping method in which a part of the blower fan 20 is immersed and applied while rotating at a low speed;
(3) A method in which the liquid is sprayed to the whole by the spray nozzle while rotating the blower fan 20.

  The dip method has the merit that the liquid can be uniformly distributed over the entire surface, and the spray method has the merit that the amount of liquid used is reduced. Although it may be determined in consideration of the size and shape of the blower fan 20, the equipment cost, and the processing cost, in the present embodiment, the dipping method is selected in order to form a liquid film on the entire surface.

  The drying step serves to fix the coating composition 200 to the resin member. Although the film can be formed even if it is allowed to stand naturally, it is possible to express desired properties such as antifouling property, contact angle with water, uniformity and dispersibility by performing the drying conditions constant. In addition, if left unattended, problems such as the particulate solid content not being dispersed and the accumulation of liquid occurring occur, so a drying step must be included. The drying process is generally blow drying using one or a plurality of drying fans provided separately. The coating composition 200 is fixed on the blower fan 20 by blowing a blow in a predetermined wind speed, temperature, time, and direction on the blower fan 20 coated with the aqueous medium.

  In this Embodiment, after apply | coating an aqueous medium to the ventilation fan 20, it dried not by blow drying but rotating the ventilation fan 20 itself. Since an aqueous medium whose viscosity is almost the same as that of water is used, the coating liquid spreads uniformly without rotation by rotating and the coating composition 200 having antifouling properties is formed on the blade 21 surface of the blower fan 20. The At the same time, particles having fungicidal or antibacterial action are exposed and dispersed on the surface.

  14 to 16 show the first embodiment. FIG. 14 shows the blade of the blower fan 20 when the concentration of the fungicide is made uniform by rotating the blower fan 20 without depending on the position of the blade 21. FIG. 15 is a view showing the concentration of the fungicide at the position 21, and FIG. 15 is inclined so that the concentration of the blade tip 24 increases from the inner peripheral portion 27 of the blade 21 constituting the blower fan 20 toward the blade tip 24. The figure which shows the density | concentration of the fungicide in the position of the braid | blade 21 of the ventilation fan 20 in the case of arrangement | positioning, FIG. 16 is the density | concentration of the fungicide in the position of the braid | blade 21 of the ventilation fan 20 at the time of rotating the ventilation fan 20 early. FIG.

  In general blow drying, when a complicated shape such as the blower fan 20 is used, it is biased depending strongly on the drying direction, and it is difficult to uniformly form the film thickness, the solid content concentration, and the mold prevention concentration. . By rotating the blower fan 20 itself, there is an effect that even a complicated shape can be formed uniformly in terms of film thickness, solid content concentration, and mold prevention concentration.

  The concentration of the fungicide 120 can be made uniform without depending on the position of the blade 21, as shown in the schematic diagram of FIG. If the temperature of the aqueous medium is increased or the rotational speed of the blower fan 20 is increased, the drying time can be shortened.

  Since the drying operation for rotating the blower fan 20 itself performs the same operation as the blower fan 20 as a normal blower or the air conditioner 100, water, dirt, and mold spores are easily attached during normal operation. There is an effect that particles having antifungal or antibacterial action tend to collect at the same site where mold tends to grow. Compared to hydrophilic inorganic fine particles and hydrophobic resin particles, particles having a relatively large particle size and having an antifungal action or antibacterial action are easily moved to the end in the centrifugal direction under centrifugal force. By adjusting the rotation speed, the concentration of the fungicide 120 from the inner peripheral portion 27 of the blade 21 toward the blade tip portion 24 (end portion in the centrifugal direction) can be adjusted.

  By rotating the blower fan 20 relatively quickly, the concentration of particles having antifungal or antibacterial action is changed from the inner peripheral portion 27 of the blade 21 constituting the blower fan 20 to the blade tip portion 24 as shown in FIG. The blade tip 24 is inclined so that the concentration of the blade tip 24 increases. That is, since the concentration of the fungicide 120 can be increased in accordance with the centrifugal direction in which mold is likely to grow, it is easy to produce a fungicide effect.

  In addition, as shown in FIG. 16, by rotating the blower fan 20 earlier, the concentration of anti-fungal or antibacterial particles present in the blade tip 24 of the blade 21 is increased in the inner peripheral portion 27 of the blade 21. It can be clearly higher than that.

  Specifically, if the blower fan 20 has a diameter of about 90 to 110 mm and the length (axial direction) of the blower fan 20 is about 600 mm, it is preferably set to 1500 rpm or more, more preferably about 2000 rpm. When the rotation is performed, the dispersibility of the inorganic particles, the resin particles, and the fungicide 120 is good, and the concentration of the blade tip 24 increases. By preferentially preventing the blade tip 24 from being moldy, it has the effect of suppressing the generation of deposits due to the mycelium at the wind inlet.

  Without kneading an antifungal agent into the resin as in the conventional example, an aqueous coating of an aqueous medium is mixed with an antifungal or antibacterial particle having an average particle size of 10 μm, more preferably 2 μm, Since it is uniformly dispersed on the surface of the resin member, it can be reliably brought into contact with the mold on the surface without being caught and deteriorating the antifouling performance.

  Since the air blowing fan 20 itself is rotated and dried and fixed using a water-based coating containing a fine anti-fungal agent, the anti-fungal agent 120 is dispersed throughout, and the tip of the blade is particularly easy to retain water and easily mold. The part 24 can be selectively disposed at a higher concentration of the fungicide 120. In particular, the growth of hyphae from the blade tip 24 can be suppressed, the air inlet is not blocked, and the air blowing performance is not deteriorated, so that energy saving can be expected.

  As described above, in the air conditioner 100 according to this embodiment, the coating film is formed on the surface of the resin component provided on the downstream side of the heat exchanger 30, and the silica fine particles 101 and the fluororesin particles are formed. 102, and the coating film is interspersed in the silica film 104 composed of the silica fine particles 101 so that the fluororesin particles 102 are partially exposed from the surface of the silica film 104, and the exposed area of the silica film 104 Is provided with the coating composition 200 that is larger than the exposed area of the fluororesin particles 102, repulsion due to amphotericity, reduction of the adhesion area due to the micro uneven structure, prevention of electrostatic adhesion due to the antistatic effect, low density and low molecular weight It prevents sticking by interstitial force and prevents various stains regardless of hydrophilicity or hydrophobicity.

  Further, the weight ratio between the content of the silica fine particles 101 and the content of the fluororesin particles 102 is set within the range of 5:95 to 35:65, and the contact angle θ with the water droplet is controlled to be 50 to 90 degrees. Therefore, even if it is a dew condensation part, the movement of dew can be suppressed and dew dripping can be prevented.

  In addition, anti-fungal or antibacterial particles having an average particle size of 10 μm, more preferably 2 μm, are mixed in an aqueous medium aqueous coating and uniformly dispersed on the surface of the resin member, thereby avoiding catching. Thus, it is possible to reliably come into contact with the mold on the surface without deteriorating the antifouling performance. In particular, when applying to the blower fan 20, the blower fan 20 itself is rotated and dried and fixed using a water-based coating containing a fine antifungal agent. It is possible to selectively increase the concentration of the fungicide 120 on the blade tip 24 where the mold is likely to be held and easily mold. Accordingly, it is possible to simultaneously provide antifouling performance against various types of dirt, suppression of dew and dripping, and effective antifungal performance that does not deteriorate the antifouling performance.

  DESCRIPTION OF SYMBOLS 10 Housing | casing, 11 Suction inlet, 12 Front grille, 13 Left and right vane, 14 Air outlet, 15 Casing part, 17 Upper and lower flaps, 18 Nozzle, 20 Blower, 21 Blade, 22 Concave surface, 23 Convex surface, 24 Blade tip part, 25 Rotation direction, 26 Mold deposit, 27 Inner circumference, 30 Heat exchanger, 31 Heat transfer tube, 32 Radiation fin, 40 Filter, 100 Air conditioner, 101 Silica fine particle, 102 Fluorine resin particle, 103 Coating film, 104 Silica film , 105 hydrophilic fouling substance, 106 hydrophobic fouling substance, 107 resin to be coated, 111 radical generating material, 112 peroxide, 120 fungicide, 200 coating composition.

Claims (5)

A blower fan that sucks air and blows out the sucked air, and includes a blower fan having a plurality of blades in the circumferential direction having a centrifugal direction end in the centrifugal direction and an inner peripheral part in the inner circumferential direction ,
The blower fan has one or both of antifouling particles of hydrophilic inorganic fine particles and hydrophobic resin particles for imparting antifouling properties, and an average particle size larger than the antifouling particles. rotates in a state of an aqueous medium in which the particles are mixed with antifungal or antibacterial activity is applied, by Rukoto drying the aqueous medium, wherein from the inner periphery toward the centrifugal direction ends proof An air blower characterized in that a coating composition in which the antifungal or antibacterial particles are dispersed is coated on the surface so that the concentration of the fungi or antibacterial particles is high . The blower device according to claim 1 , wherein the coating composition is a hydrophilic / hydrophobic composite surface including both hydrophilic inorganic fine particles and hydrophobic resin particles. As the hydrophilic inorganic fine particles, silica fine particles having an average particle size in the range of 4 to 30 nm,
The hydrophobic resin particles include fluororesin particles having an average particle size in the range of 50 to 500 nm,
The blower according to claim 2 , wherein the fluororesin particles are scattered in the film made of the silica fine particles so as to be exposed from the surface of the film made of the silica fine particles. The air blower according to any one of claims 1 to 3, wherein the antifungal or antibacterial particles are atomized until the average particle size becomes 10 µm or less. Average particle diameter of atomization process until 2μm or less is applied, according to any one of claims 1 to 4 wherein the antifungal or particles having an antibacterial action, or radical material is characterized in that mixed Blower.