JPH11138014A - Photocatalyst body and apparatus employing photocatalyst body for purifying interior of refrigerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To heighten the ultraviolet ray absorbing capability of a photocatalyst particle having high catalytic activity by forming a layer of an ultraviolet ray transmissive medium combined with the photocatalyst particle or in which the photocatalyst particle is dispersed on a substrate surface. SOLUTION: Any one of glass, an inorganic sintered body, and a metal is used as a material of a substrate 1 to form a photocatalyst on it and a solution produced by suspending a fine titanium oxide particle in an alkoxysilicone type compound is applied to the surface of the substrate 1 and then the resultant substrate is fired to form a layer of a photocatalyst body 4 comprising an ultraviolet ray transmissive medium 3, which is a silicon oxide film, and a photocatalyst particle 2 dispersed in the inside and the surface of the medium 3. By immobilizing the photocatalyst particle 2 in the ultraviolet ray transmissive medium 3 in such as manner and in the case a material such as quartz glass transparent to ultraviolet rays is used as the substrate 1, ultraviolet rays are not absorbed by the substrate 1 and the ultraviolet ray transmissive medium 3 and efficiently reach the photocatalyst particle 2 even if ultraviolet rays are radiated from the substrate 1 side and consequently, high deodorization performance is carried out.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photocatalyst having high deodorizing performance and a refrigerator using the same.

[0002]

2. Description of the Related Art Conventionally, when titanium oxide is used as a photocatalytic material as a film-like photocatalyst, an alkoxytitanate compound is applied on the surface of a bulb having ultraviolet permeability as a substrate or on the metal surface of a light reflecting plate. Some of them are baked to form a thin film having a film thickness of submicron order and a smooth surface. By adopting such a structure, the surface of the film-shaped photocatalyst is smooth, and the thickness thereof is on the order of sub-micron, so that visible light can be transmitted, and a photocatalyst that is also used as an illumination lamp using visible light is proposed. (JP-A-9-57113). On the other hand, a conventional refrigerator deodorizing device is provided with a platinum group catalyst provided with a heater for regeneration, in which an inorganic oxide catalyst such as manganese oxide formed in a honeycomb shape is provided in an air circulation path outside a refrigerator. There is a configuration in which any one of a block-shaped photocatalyst and a separately-configured excitation ultraviolet lamp is adopted (Japanese Patent No. 2574840).

[0003]

However, when focusing on the essential problem of the catalytic activity of the photocatalyst itself,
Since the surface of the conventional film-shaped photocatalyst is smooth, the specific surface area is smaller than that of the particulate material or the like, and it is difficult to increase the contact ratio with the odor component molecules. For this reason, it is difficult to sufficiently exhibit the catalytic activity. Further, in the case of using light having a wavelength of ultraviolet light, the conventional film-shaped photocatalyst absorbs almost all ultraviolet light, even if it is a thin film having a smooth surface. For this reason, when a conventional film-shaped photocatalyst is provided on the surface of the ultraviolet lamp, the emission of ultraviolet light from the ultraviolet lamp into the gas phase is almost blocked, and it is impossible to simultaneously sterilize bacteria floating in the gas phase. Near possible. On the other hand, in the above-mentioned conventional refrigerator purifying device, the catalyst exhibits a decomposition and regeneration effect for a specific odor component such as mercaptan, but simply adsorbs to other odor components such as ethanol and amine. It only shows the action as a material. For this reason, there was a difficulty in deodorizing life design. In the case of (1), there is a problem that the refrigerator has a new heat load because the heater surface rises to about 200 ° C. because of a long service life and a high deodorizing effect. Furthermore, although it has characteristics that can be put to practical use in terms of life and performance, the catalyst and the ultraviolet lamp are separately provided, so that the structure must be complicated.

[0004] The present invention has been made in view of the above,
An object of the present invention is to provide a photocatalyst capable of sufficiently exhibiting catalytic activity, improving deodorizing performance, and improving durability. Another object of the present invention is to provide a long-life refrigerator purifying apparatus having high deodorizing performance and sterilizing performance.

[0005]

According to a first aspect of the present invention, there is provided a photocatalyst comprising, on a surface of a substrate, a layer in which photocatalyst particles are dispersed and combined in an ultraviolet transmitting medium. Is the gist. With this configuration, it is possible to increase the ability of the photocatalytic particles having strong catalytic activity to absorb ultraviolet light.

[0006] The photocatalyst according to claim 2 is the photocatalyst according to claim 1.
In the photocatalyst described above, the gist is that any one of glass, an inorganic sintered body, and a metal is used as the substrate. With this configuration, the layer can be appropriately formed while sufficiently withstanding the temperature at the time of firing or the like in the step of forming the layer in which the photocatalyst particles are dispersed and combined with the ultraviolet-transparent catalyst.
Further, the durability of the layer can be improved.

The photocatalyst according to the third aspect is the photocatalyst according to the first aspect.
In the photocatalyst described above, the gist is that a silicon oxide compound film is used as the ultraviolet light transmitting medium. With this configuration, the ultraviolet rays reach the photocatalyst particles efficiently without being substantially absorbed by the ultraviolet ray transmitting medium.

[0010] The photocatalyst according to claim 4 is the photocatalyst according to claim 1.
In the photocatalyst described above, the gist is that any one of anatase type titanium oxide and zinc oxide is used as the photocatalyst particles. With this configuration, high catalyst activity is obtained.

The photocatalyst according to claim 5 is the photocatalyst according to claim 4.
The photocatalyst according to the above, wherein the diameter of the photocatalyst particles is 0.3
It is a gist that the thickness is not more than μm. With this configuration, it is possible to sufficiently increase the ultraviolet absorbing ability.

The photocatalyst according to claim 6 is the photocatalyst according to claim 1.
In the photocatalyst described above, the point is that the surface roughness of the dispersed and combined layer is Rmax 0.3 to 100 μm. With this configuration, the surface roughness is 0.3 μm
By doing so, the contact ratio with the air to be treated is improved, and high purification performance can be exhibited. When the thickness is 100 μm or less, the film strength is sufficiently maintained.

According to a seventh aspect of the present invention, there is provided a purifying apparatus in a refrigerator, comprising: the photocatalyst according to the first aspect; and an in-compartment ultraviolet light for exciting the photocatalyst. With this configuration, the ultraviolet light emitted from the in-compartment ultraviolet light is incident on the photocatalyst, is efficiently absorbed by the photocatalyst particles, and the photocatalyst is activated, and high deodorizing performance is obtained. At the same time, the germicidal action of the bacteria floating in the refrigerator by the emitted ultraviolet light itself is obtained.

According to an eighth aspect of the present invention, there is provided the purifying apparatus for a refrigerator according to the seventh aspect, wherein a cold cathode sterilizing lamp or a cold cathode type black fluorescent lamp is provided as the base of the photocatalyst, which is the ultraviolet light in the refrigerator. The gist is to use any of these. With this configuration, the ultraviolet light emitted from the cold cathode germicidal lamp or the cold cathode black fluorescent lamp is directly incident on the photocatalyst, and is more efficiently absorbed by the photocatalyst particles, so that high deodorizing performance can be obtained. Further, by using a cold cathode sterilizing lamp or a cold cathode type black fluorescent lamp, a practically sufficient device life can be ensured in a relatively low temperature atmosphere in the refrigerator.

According to a ninth aspect of the present invention, in the refrigerator, the photocatalyst is provided on a side of the lamp surface facing the circulating air flow in the refrigerator. Is the gist. With this configuration, it is possible to increase the contact ratio between the contaminant molecules and the photocatalyst with a limited amount of the photocatalyst used. In addition, since there is no absorption of ultraviolet rays by the photocatalyst from the side not facing the circulating airflow in the refrigerator, it is possible to efficiently sterilize bacteria floating in the refrigerator.

According to a tenth aspect of the present invention, there is provided the purifying apparatus for a refrigerator according to the seventh aspect, wherein at least one of a trough or a reflecting plate, a circulating cool air duct, or a fan for circulating cool air in the ultraviolet illuminating device in the refrigerator. The gist is that the photocatalyst is provided on the surface of the photocatalyst. With this configuration, the area of the photocatalyst, that is, the amount of photocatalyst particles to be mounted increases, and the deodorizing performance can be further improved.

According to a eleventh aspect of the present invention, in the purifying apparatus for a refrigerator according to the seventh aspect, the lighting control of the ultraviolet light in the refrigerator is performed by detecting operation of a cooling air circulation fan or controlling time for a predetermined time. The gist is to perform at least one of them. With this configuration, the ultraviolet light in the refrigerator is periodically turned on, and the photocatalyst is effectively activated.
High purification performance can be always obtained, and the life of the ultraviolet light in the refrigerator, that is, the life of the apparatus can be prolonged.

According to a twelfth aspect of the present invention, there is provided the purifier for a refrigerator according to the eleventh aspect, further comprising a timer that operates in conjunction with the operation of the fan for circulating the cool air. When the operation is detected, the timer operates, and when the cool air circulation fan does not operate for 15 minutes or more, the operation of the timer takes precedence, and when the cool air circulation fan operates for 15 minutes or more, this operation takes precedence. The gist of the invention is to turn on the ultraviolet light in the refrigerator for a predetermined time of 15 minutes or more. With this configuration, the ultraviolet light in the refrigerator is turned on periodically and for a sufficient time to activate the photocatalyst reliably, and always obtain high purification performance.

According to a thirteenth aspect of the present invention, there is provided the purifier for a refrigerator according to the eleventh aspect, wherein the ultraviolet light in the refrigerator is turned on for 15 minutes when the cooling air circulation fan is not operated within three hours. The gist is to light up for the above-mentioned predetermined time. With this configuration, even if there is no operation of the cooling air circulation fan for a long time,
And it lights up for a sufficient time and the photocatalyst is activated reliably,
High purification performance is always ensured.

[0018]

Embodiments of the present invention will be described below with reference to the drawings.

An embodiment of the photocatalyst will be described with reference to FIGS. In FIG. 1, reference numeral 1 denotes a substrate (substrate) for forming a photocatalyst, which is made of glass, an inorganic sintered body, or a metal and which withstands the firing temperature of the photocatalyst (about 500 ° C.). Anything that can be used may be used. The surface of the substrate 1 is coated with a solution in which titanium oxide fine particles are suspended in an alkoxysilicone compound, and then baked, whereby the photocatalyst particles 2 are formed in and on the ultraviolet-permeable medium 3 made of a silicon oxide compound film. Are dispersed to form a layered photocatalyst 4.
The photocatalyst particles 2 are semiconductors and have an energy band gap. When the semiconductor is irradiated with light in the ultraviolet region, electrons in the valence band gain the energy of ultraviolet rays and jump into the conduction band, and holes from which the electrons have jumped are formed in the valence band. OH radicals are generated from the surface of the semiconductor, that is, the photocatalyst particles 2 in this excited state.

Hole + surface hydroxyl group (OH ⁻ ) → OH radical The OH radical has a very strong oxidizing power and the photocatalyst particles 2
The malodorous component adsorbed on the surface is oxidatively decomposed by this oxidizing power, and a deodorizing effect is obtained. Even with the same photocatalyst, the particulate photocatalyst has a characteristic that the catalytic activity is stronger than that of the conventional thin-film photocatalyst 2 'shown as a comparative example in FIG. The photocatalyst particles 2 are made of anatase-type titanium oxide or zinc oxide, which is highly active in nature, and has a particle size of 0.3.
It is desirable that the thickness be not more than μm. When the thickness is 0.3 μm or less, it is possible to sufficiently increase the ultraviolet absorbing ability.
In this embodiment, since the photocatalyst particles 2 having stronger catalytic activity can be formed by being fixed on the surface of the photocatalyst 4, high deodorizing performance can be obtained. Further, the surface roughness of the photocatalyst 4 is required to be Rmax 0.3 μm or more in order to improve the contact rate with the air to be treated and express high purification performance, and to be Rmax 100 μm or less from the viewpoint of maintaining film strength. There is.

In this embodiment, since the photocatalyst particles 2 are fixed by the ultraviolet transmitting medium 3, if a material transparent to ultraviolet light such as quartz glass is used for the substrate 1, the ultraviolet light is incident from the substrate 1 side. Even if it does, the ultraviolet rays are not absorbed by the base 1 and the ultraviolet-permeable medium 3, it can reach the photocatalyst particles 2 efficiently, and high deodorizing performance can be realized. Conversely, when ultraviolet light is irradiated from the opposite side of the substrate 1, that is, from the side of the photocatalyst body 4, the photocatalyst particles 2 have a large surface roughness.
, A high deodorizing performance can be similarly obtained.

Referring to FIGS. 3 and 4, a first embodiment of the purifying apparatus in a refrigerator will be described. 3A and 3B show an in-compartment purifying device, wherein FIG. 3A is a perspective view, and FIG. 3B is a cross-sectional view taken along line AA of FIG. The photocatalyst 4 is coated on the surface of the quartz glass tube of the cold cathode germicidal lamp 5 serving as ultraviolet light in the refrigerator. 6 is a cold cathode sterilization lamp 5
Is an electrode bushing. Ultraviolet rays emitted from the cold cathode sterilization lamp 5 directly enter the photocatalyst 4 and activate the photocatalyst 4. As described in the above-described embodiment of the photocatalyst, the photocatalyst 4 is formed of the ultraviolet-permeable medium 3.
Since the photocatalyst particles 2 are dispersed inside and on the surface, the incident ultraviolet rays are efficiently absorbed by the photocatalyst particles 2 and exhibit high catalytic activity, that is, high deodorizing performance. FIG. 4 shows a refrigerator equipped with the in-compartment purifying device 8. Reference numeral 11 denotes a refrigerator main body, which includes a refrigerator compartment 12, a low-temperature vegetable compartment 13, a first freezing compartment 14, and a second freezing compartment 15 from above. In each room, food can be taken in and out by opening and closing the respective opening and closing doors 16, 17, 18, and 20. 20 is a refrigerator evaporator, 9 is a fan for circulating cool air in the refrigerator 12, 10 is a duct for returning the circulating cold air flow in the refrigerator 12 and the cold vegetable compartment 13 to the refrigerator evaporator 20, 21 is a refrigerator evaporator , 22 are compressors. Internal purifier 8
Is installed in the duct 10 to decompose and deodorize odor components generated from foods and vegetables in the refrigerator compartment 12 and the low-temperature vegetable compartment 13 and sterilize floating bacteria. The cool air flows through a duct 10 provided with an in-compartment purifying device 8 therein, and when the odor component molecules contained in the cold air come into contact with the photocatalyst 4 of the in-compartment purifying device 8, they are oxidized and decomposed to deodorize components. . Since the amount of heat generated by the cold cathode sterilization lamp 5 is small, the effect is extremely small in that the influence on the cooling performance of the refrigerator is extremely small. In this respect, when compared with a conventional purification device combining a regeneration heater and a platinum group catalyst, in this comparative example, a regeneration heater is used, so that the heat load deteriorates the cooling performance of the refrigerator. Further, in the comparative example, convection occurs due to heating of air near the regeneration heater, which is a factor that hinders contact between the odor component molecules and the catalyst of the purification device, and it is difficult to obtain the original deodorizing effect of the catalyst.

Since the photocatalyst 4 is excited by ultraviolet rays, any lamp capable of emitting ultraviolet rays can be used as the base of the photocatalyst 4, that is, as an ultraviolet light source. It is particularly desirable to use a cold cathode germicidal lamp or a cold cathode black fluorescent lamp from the viewpoint of the life of the purifier. When the photocatalyst 4 is coated on the inner surface of the duct 10 shown in FIG.
, That is, the amount of photocatalyst particles to be mounted is increased, and the deodorizing performance can be further improved.

If the method of controlling the operation of the cooling air circulating fan 9 or the method of controlling the time is adopted as the lighting control of the above-mentioned interior ultraviolet illumination (lamp 5), the effect on activation of the photocatalyst 4 can be obtained. It is possible to provide a system that is suitable and has a longer lamp life, that is, a longer life of the purifier in the refrigerator. Specifically, as a lighting control method by detecting the operation of the cool air circulation fan 9, when the operation of the cool air circulation fan 9 is detected, a timer (not shown) is operated in conjunction therewith, and the cool air circulation fan 9 is operated. When the cooling air circulation fan 9 is not operated for more than 15 minutes, the operation of the timer is prioritized, and when the cooling air circulation fan 9 is operated for 15 minutes or more, this is prioritized, and the ultraviolet light in the refrigerator is turned on for a predetermined time of 15 minutes or more. On the other hand, as a time control method, when the operation of the cool air circulation fan 9 is not performed within three hours, the in-compartment ultraviolet light is turned on and is turned on for a predetermined time of 15 minutes or more.

FIG. 5 shows a second embodiment of the purifier in the refrigerator. In the present embodiment, the photocatalyst 4 is selectively provided on the side of the cold cathode germicidal lamp 5, which is the base, facing the circulating cold airflow. With such a structure, since the odor component molecules in the circulating cold airflow mainly collide with the surface on the side facing the circulating cold airflow, high deodorizing performance can be obtained with a limited amount of the photocatalyst 4 used. it can. At the same time, ultraviolet rays are radiated from the surface of the lamp 5 on the opposite side where the photocatalyst 4 is not provided, into the duct 10 without being blocked by the photocatalyst 4 at all, so that they float in the space inside the duct 10. Bacteria can be killed efficiently. The lighting control of the in-compartment ultraviolet illumination (lamp 5) is performed in the same manner as in the first embodiment.

[0026]

As described above, according to the photocatalyst of the first aspect, since a layer in which photocatalyst particles are dispersed and combined in an ultraviolet-permeable medium is provided on the surface of the base material, the photocatalyst has strong catalytic activity. The ability to absorb ultraviolet light into the photocatalyst particles is enhanced, and the deodorizing performance can be improved.

According to the photocatalyst of the second aspect, since any one of glass, inorganic sintered body and metal is used as the base material, the layer in which the photocatalyst particles are dispersed and combined in the ultraviolet transmitting medium is properly formed. The catalyst can be formed to sufficiently exhibit catalytic activity, improve deodorizing performance, and improve durability.

According to the photocatalyst of the third aspect, since the silicon oxide compound film is used as the ultraviolet ray transmitting medium, the ultraviolet rays can efficiently reach the photocatalyst particles and the deodorizing performance can be improved.

According to the photocatalyst of the fourth aspect, since either the anatase type titanium oxide or the zinc oxide is used as the photocatalyst particles, a high catalytic activity can be obtained and the deodorizing performance can be improved.

According to the photocatalyst of the present invention, the diameter of the photocatalyst particles is set to 0.3 μm or less, so that the ultraviolet absorbing power can be sufficiently increased and the deodorizing performance can be improved.

According to the photocatalyst of the sixth aspect, the surface roughness of the dispersed / combined layer is Rmax 0.3 to 100.
Since it is set to μm, the contact ratio with the air to be treated is improved, the deodorizing performance can be improved, and the film strength can be sufficiently maintained.

According to the seventh aspect of the present invention, the apparatus for purifying the inside of a refrigerator includes the photocatalyst according to the first aspect of the present invention and the ultraviolet light in the refrigerator for exciting the photocatalyst. Ultraviolet rays can be efficiently absorbed by the photocatalyst particles to achieve a high deodorizing performance, and the emitted ultraviolet rays themselves can kill bacteria floating in the refrigerator.

According to the purifying apparatus in the refrigerator of the present invention, since either the cold cathode germicidal lamp or the cold cathode type black fluorescent lamp which is the ultraviolet light in the refrigerator is used as the base of the photocatalyst body, the lamp emits light. The emitted ultraviolet rays are directly incident on the photocatalyst, and are more efficiently absorbed by the photocatalyst particles, so that the deodorizing performance can be further improved. Also,
By using a cold cathode sterilization lamp or a cold cathode black fluorescent lamp, the life of the apparatus can be extended in a relatively low temperature atmosphere in the refrigerator.

According to the ninth aspect of the present invention, since the photocatalyst is provided on the side of the lamp surface facing the circulating air flow in the refrigerator, high deodorizing performance can be achieved with a small amount of photocatalyst used. be able to. In addition, since there is no absorption of ultraviolet rays by the photocatalyst from the side that does not face the circulating air flow in the refrigerator, the bacteria floating in the refrigerator can be efficiently sterilized.

According to the purifying apparatus in the refrigerator, the photocatalyst is provided on at least one surface of the trough or the reflector, the circulating cool air duct or the cool air circulating fan blade in the in-compartment ultraviolet lighting apparatus. The amount of photocatalyst particles to be mounted is increased, so that the deodorizing performance can be further improved.

According to the eleventh aspect of the present invention, as the lighting control of the ultraviolet light in the refrigerator, at least one of the operation detection of the cooling air circulation fan and the time control for a predetermined time is performed. The body is activated regularly, and high purification performance can always be obtained.
Further, the life of the device can be extended.

According to the twelfth aspect of the present invention, the refrigerator has a timer which operates in conjunction with the operation of the cool air circulation fan, and operates when the operation of the cool air circulation fan is detected. And the cooling air circulation fan
When not operating for more than a minute, the operation of the timer takes precedence, and when the cooling air circulation fan operates for 15 minutes or more, the operation takes precedence and the ultraviolet light in the refrigerator is turned on for a predetermined time of 15 minutes or more, The photocatalyst is periodically and sufficiently activated, and high purification performance can always be ensured.

According to the thirteenth aspect of the present invention, when the cool air circulation fan is not operated within three hours, the ultraviolet light in the refrigerator is turned on for a predetermined time of 15 minutes or more. Even when the cooling air circulation fan does not operate for a long time, the photocatalyst is periodically and sufficiently activated, and high purification performance can always be ensured.

[Brief description of the drawings]

FIG. 1 is a diagram showing a cross-sectional structure of a photocatalyst according to an embodiment of the present invention.

FIG. 2 is a diagram showing a cross-sectional structure of a comparative example of the embodiment of the photocatalyst.

FIG. 3 is a perspective view and a cross-sectional view showing a first embodiment of a purifier in a refrigerator according to the present invention.

FIG. 4 is a longitudinal sectional view of a refrigerator in which an embodiment of the above-described refrigerator cleaning apparatus is mounted.

FIG. 5 is a cross-sectional view showing a second embodiment of the purifier in the refrigerator according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate (substrate) 2 Photocatalyst particles 3 Ultraviolet-permeable medium 4 Photocatalyst 5 Cold cathode sterilization lamp 8 In-room purification device 9 Cooling air circulation fan 10 Duct

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Toru Kubota 8 Shinsugita-cho, Isogo-ku, Yokohama-shi, Kanagawa Inside Toshiba Living Space Systems Research Institute

Claims (13)

[Claims] 1. A photocatalyst, comprising a layer in which photocatalyst particles are dispersed and combined in an ultraviolet-permeable medium on a surface of a substrate. 2. The photocatalyst according to claim 1, wherein the substrate is made of one of glass, an inorganic sintered body and a metal. 3. The photocatalyst according to claim 1, wherein a silicon oxide compound film is used as the ultraviolet transmitting medium. 4. The photocatalyst according to claim 1, wherein the photocatalyst particles are made of either anatase type titanium oxide or zinc oxide. 5. The photocatalyst according to claim 4, wherein the diameter of the photocatalyst particles is 0.3 μm or less. 6. The photocatalyst according to claim 1, wherein the surface roughness of the dispersed and combined layer is Rmax 0.3 to 100 μm. 7. A purifying apparatus in a refrigerator, comprising: the photocatalyst according to claim 1; and ultraviolet light in a refrigerator for exciting the photocatalyst. 8. The refrigerator purifying apparatus according to claim 7, wherein one of a cold cathode germicidal lamp and a cold cathode black fluorescent lamp, which is the ultraviolet light in the refrigerator, is used as a base of the photocatalyst body. . 9. The purifying device according to claim 8, wherein the photocatalyst is provided on a side of the lamp surface facing the circulating air flow in the refrigerator. 10. The refrigerator according to claim 7, wherein the photocatalyst is provided on at least one surface of a trough or a reflector, a circulating cool air duct, or a fan for circulating cool air in an in-compartment ultraviolet lighting device. Internal purification device. 11. The refrigerator purifying apparatus according to claim 7, wherein the lighting control of the in-compartment ultraviolet lighting includes at least one of operation detection of a cool air circulation fan and time control for a predetermined time. 12. A timer that operates in conjunction with the operation of the cool air circulation fan, the timer operates when the operation of the cool air circulation fan is detected, and the cool air circulation fan is operated for 15 minutes or more. When not operating, the operation of the timer takes precedence, and when the cool air circulation fan operates for 15 minutes or more, this operation takes precedence and the ultraviolet light in the refrigerator is set to 15 times.
The purifier in a refrigerator according to claim 11, wherein the light is turned on for a predetermined time period of at least one minute. 13. The refrigerator purifying apparatus according to claim 11, wherein if the cooling air circulation fan is not operated within three hours, the in-compartment ultraviolet light is turned on for a predetermined time of 15 minutes or more.