Cultivation shed

Abstract

To provide a cultivation shelf that makes it possible to readily improve an amount of light necessary for the growth of plants.SOLUTION: A cultivation shelf 1 has a shelf part 2 for mounting plants thereon, and a light source 3 that emits light for application to the plants mounted on the shelf part 2. A light reflection part 50 is above the shelf part 2. The light source 3 is provided directly under the light reflection part 50.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a cultivation shelf, and more particularly to a cultivation shelf suitable for use in a plant factory or the like. [Background technology]

[0002] Conventionally, there have been proposed plant factories in which the environment necessary for plant growth is constructed almost artificially. In such plant factories, shelves suitable for plant growth are used. For example, Patent Document 1 describes a cultivation shelf having a growth chamber for growing plants, in which a light source for irradiating light to plants placed in the growth chamber is provided on the top wall. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-18077 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the above-mentioned cultivation shelves, it is desirable to increase the amount of light from the light source to promote plant growth.

[0005] The present invention has been made in consideration of the above points, and has an object to provide a cultivation shelf that can easily increase the amount of light required for plant growth. [Means for solving the problem]

[0006] One embodiment of the cultivation shelf according to the present invention is a cultivation shelf comprising a shelf portion for placing plants and a light source for emitting light to irradiate the plants placed on the shelf portion, the cultivation shelf comprising a light reflecting portion above the shelf portion having a light reflectance of 85% or more, and the light source directly below the light reflecting portion.

[0007] In the cultivation shelf, the light reflecting portion preferably has a coating layer having a titanium oxide content of 35% by mass or more and 85% by mass or less.

[0008] In the cultivation shelf, the photosynthetic photon flux density in the shelf portion when the light source emits light is 100 μmol m -2 s -1 More than 400 μmol m -2 s -1 It is preferable that:

[0009] In the cultivation shelf, it is preferable that the light reflecting portion is provided with a multi-layer coating film, the multi-layer coating film has a primer layer and a topcoat coating film layer on the primer layer, and the light source is arranged on the surface of the multi-layer coating film.

[0010] The cultivation shelf preferably has a light reflecting surface on at least one of the top, side and back of the shelf portion.

[0011] In the cultivation shelf, it is preferable that the light reflecting portion further includes a photocatalyst layer, and the photocatalyst layer contains anatase type titanium oxide. Effect of the Invention

[0012] Since the present invention has a light source directly below the light reflecting portion, the light emitted from the light source is more easily reflected by the light reflecting portion, making it easier to increase the amount of light required for growing plants on the shelf portion. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1A is a schematic front view showing one embodiment of a cultivation shelf according to the present invention, FIG. 1B is a schematic plan view of the same, and FIG. 1C is a schematic sectional view of the same. [Diagram 2] FIG. 2 is a perspective view showing one embodiment of the cultivation shelf according to the present invention. [Diagram 3] FIG. 3 is a partially cutaway perspective view showing one embodiment of the cultivation shelf according to the present invention. [Figure 4]FIG. 4 is a schematic cross-sectional view showing a light source and a light reflecting portion of the cultivation shelf according to the present invention. [Diagram 5] FIG. 5 is a perspective view showing one embodiment of the cultivation shelf according to the present invention. [Figure 6] Fig. 6A is a perspective view showing an example of an auxiliary reflection member, Fig. 6B is a horizontal cross-sectional view showing a state in which the auxiliary reflection member of Fig. 6A is attached, and Fig. 6C is a vertical cross-sectional view showing a state in which the auxiliary reflection member of Fig. 6A is attached. [Figure 7] Fig. 7A is a perspective view showing another example of an auxiliary reflection member, Fig. 7B is a horizontal cross-sectional view showing a state in which the auxiliary reflection member of Fig. 7A is attached, and Fig. 7C is a vertical cross-sectional view showing a state in which the auxiliary reflection member of Fig. 7A is attached. [Figure 8] Fig. 8A is a perspective view showing another example of an auxiliary reflection member, Fig. 8B is a horizontal cross-sectional view showing a state in which the auxiliary reflection member of Fig. 8A is attached, and Fig. 8C is a vertical cross-sectional view showing a state in which the auxiliary reflection member of Fig. 8A is attached. [Figure 9] Fig. 9A is a perspective view showing another example of an auxiliary reflection member, Fig. 9B is a horizontal cross-sectional view showing a state in which the auxiliary reflection member of Fig. 9A is attached, and Fig. 9C is a vertical cross-sectional view showing a state in which the auxiliary reflection member of Fig. 9A is attached. [Figure 10] FIG. 10 is a graph showing the measurement results of illuminance and photosynthetic photon flux density in Example 1. [Figure 11] FIG. 11 is a graph showing the measurement results of illuminance and photosynthetic photon flux density in Example 2. [Figure 12] FIG. 12 is a graph showing the measurement results of illuminance and photosynthetic photon flux density in Comparative Example 1. [Figure 13] FIG. 13 is a graph showing the measurement results of illuminance and photosynthetic photon flux density in Comparative Example 2. [Figure 14] FIG. 14 is a graph showing the measurement results of illuminance and photosynthetic photon flux density in Comparative Example 3. [Figure 15] FIG. 15 is a graph showing the measurement results of illuminance and photosynthetic photon flux density in Comparative Example 4. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, an embodiment of the present invention will be described.

[0015] FIG. 1 shows a cultivation shelf 1 of this embodiment. This cultivation shelf 1 is equipped with a plurality of shelf parts 2 and a light source 3. The plurality of shelf parts 2 are attached to a plurality of supports 21, respectively, and are arranged in a vertical line, and the interval between adjacent shelf parts 2 is formed to a dimension capable of accommodating plants. A cultivation container 4 such as a cultivation bed is arranged on the upper surface of the shelf part 2, and plants are cultivated in the cultivation container 4. The light source 3 emits light to irradiate the plants arranged on the shelf part 2. An entrance 6 is formed on the front surface of the cultivation shelf 1 for putting plants and the cultivation container 4 in and taking them out of each shelf part 2. A ceiling part 7 is formed on the upper surface of the cultivation shelf 1. A back part 8 is formed on the back surface of the cultivation shelf 1 (the surface opposite to the entrance 6). Side wall parts 10 are formed on both side surfaces of the cultivation shelf 1.

[0016] As shown in FIG. 2 and FIG. 3, the cultivation shelf 1 has a plurality of light reflecting portions 50. Each light reflecting portion 50 is formed in a plate shape and has a light reflecting surface (first light reflecting surface) 9 with a light reflectance of 85% or more. For example, the entire surface of the light reflecting portion 50 is formed as the light reflecting surface 9. When light is irradiated from the light source 3, the light reflecting portion 50 reflects the light at the light reflecting surface 9. The light reflecting portion 50 is formed above each shelf portion 2. Above the uppermost shelf portion 2a, the light reflecting portion 50 is formed immediately below the ceiling portion 7. Also, above the second shelf portion 2 from the top and below, the light reflecting portion 50 is formed immediately below the other shelf portions 2. That is, the light reflecting portion 50 is provided between the shelf portions 2 adjacent to each other in the vertical direction.

[0017] The light source 3 is provided directly below the light reflecting surface 9 of each light reflecting portion 50. Examples of the light source 3 include fluorescent lamps and light emitting diodes (LEDs). When providing the light source 3 directly below the light reflecting portion 50, the light source 3 can be brought into contact with the light reflecting surface 9 and bonded thereto. Also, the case where there is a slight gap (5 mm or less) between the light source 3 and the light reflecting surface 9 is also included in providing the light source 3 directly below the light reflecting portion 50. When the light source 3 is provided directly below the light reflecting portion 50 in this way, the light emitted from the light source 3 can easily reach the light reflecting surface 9, and the light emitted from the light source 3 can be efficiently diffused by the light reflecting surface 9. Therefore, the light from the light source 3 can easily reach every corner of the upper surface of the shelf portion 2 below the light reflecting portion 50, which can improve the photosynthetic photon flux density and facilitate the growth of plants. If the light source 3 is away from the light reflecting section 50, for example, if a power supply section for supplying power to the light source 3 or a control section for controlling the turning on and off of the light source 3 is located between the light source 3 and the light reflecting section 50, it may be difficult for the light emitted from the light source 3 to reach the light reflecting section 50, making it difficult for light reflection and light diffusion to occur at the light reflecting section.

[0018] 3, in this embodiment, electrical equipment 31 such as a control unit, power supply unit, and wiring for the light source 3 is provided between the light reflecting unit 50 and the shelf unit 2 immediately above it. The uppermost electrical equipment 31 is also provided between the uppermost light reflecting unit 50 and the ceiling unit 7. Therefore, the electrical equipment 31 is not provided between the light source 3 and the shelf unit 2 immediately below it, and the light emitted from the light source 3 and the light reflected by the light reflecting surface 9 are less likely to be blocked by the electrical equipment 31.

[0019] The light reflecting surface 9 of the light reflecting portion 50 has a reflectance of light (ultraviolet light and visible light) of 85% or more. In this case, the light emitted from the light source 3 can easily reach every corner of the upper surface of the shelf portion 2 below the light reflecting portion 50. In addition, the photosynthetic photon flux density on the upper surface of the shelf portion 2 below the light reflecting portion 50 can be easily improved. If the light reflectance of the light reflecting portion 50 is less than 85%, the light reflectivity of the light reflecting portion 50 may decrease, making it difficult to improve the photosynthetic photon flux density. Here, the "reflectance" is defined as a percentage when the gloss of the reference surface is set to 100 by measuring the reflectance of light according to the 60-degree specular gloss measurement method described in JIS K 5600-4-7 (1999). The upper limit of the specular gloss is 100%.

[0020] The light reflecting portion 50 preferably has a diffuse reflectance of 85% or more at a light wavelength of 550 nm. In this case, the light reflecting surface 9 of the light reflecting portion 50 is formed as a light diffusing surface, and the light reflecting portion 50 reflects light while diffusing it. This makes it easier for light to reach every corner of the upper surface of the shelf portion 2 below the light reflecting portion 50. It also makes it easier to improve the photosynthetic photon flux density on the upper surface of the shelf portion 2 below the light reflecting portion 50.

[0021] Here, "diffuse reflectance" refers to the diffuse reflectance of light with a wavelength of 550 nm, not including specular reflection, measured by an integrating sphere. This diffuse reflectance is specified as a percentage of the diffuse reflectance of a wavelength of 550 nm measured using a diffuse reflectance measuring device using an integrating sphere, with a reference white plate taken as 100. An example of a diffuse reflectance measuring device is the "CM-3700d" manufactured by Minolta Co., Ltd. (now Konica Minolta, Inc.). Diffuse reflectance is measured in accordance with JIS Z 8722 geometric condition c, etc., and an integrating sphere (a sphere whose inner surface is coated with white paint such as barium sulfate that almost completely diffusely reflects light) is used to measure the reflectance at a wavelength of 550 nm, with diffuse illumination received at an 8° angle, as a percentage of the reference white plate (made of barium sulfate). The SCE (specularly reflected light excluded) method, which is a method of measuring light by removing specular reflection, can be used to measure diffuse reflectance. The SCE method removes specular reflected light and measures only diffuse reflected light, resulting in an evaluation of color and gloss that is closer to that seen with the naked eye. The upper limit of diffuse reflectance for highly light-diffusing painted steel sheets is 100%.

[0022] The photosynthetic photon flux density is a unit expressed by the number of photons, which are particles of light. Photosynthesis depends on the number of photons incident on chlorophyll, and 8 to 10 photons are required to consume one molecule of carbon dioxide through photosynthesis. Therefore, the photosynthetic photon flux density indicates the number of photons incident per unit time and unit area in the wavelength range of 400 to 700 nm, which is the absorption wavelength range of chlorophyll. In this embodiment, the photosynthetic photon flux density on the upper surface of the shelf portion 2 is 100 μmol m -2 s -1 More than 400 μmol m -2 s -1 Within this range, a sufficient photosynthetic photon flux density required for plant growth can be obtained, and unnecessary power consumption by the light source 3 can be reduced.

[0023] The light reflecting portion 50 as described above is provided with a multi-layer coating film 32 having a coating film layer with a content of rutile-type titanium oxide of 35% by mass or more and 85% by mass or less. As shown in FIG. 4, the multi-layer coating film 32 can be formed with a primer layer 30, a top-coat coating film layer 31 on the primer layer 30, and a photocatalyst layer 36 formed on the top-coat coating film layer 31 via a protective layer 35. The coating film layer with a content of rutile-type titanium oxide of 35% by mass or more and 85% by mass or less can be formed as the top-coat coating film layer 31. In such a multi-layer coating film 32, the primer layer 30, the top-coat coating film layer 31, the protective layer 35, and the photocatalyst layer 36 are each formed of a coating film, and the light reflectivity of the light reflecting portion 50 can be easily adjusted by adjusting the thickness and components of each coating film. The surface of the multi-layer coating film 32 is formed as a light reflecting surface 9, and a light source 3 is provided in contact with or in close proximity to the light reflecting surface 9.

[0024] The light reflecting portion 50 can be formed by using a high light reflective coated steel plate. The light reflecting portion 50 can also be formed by using a high light diffusion coated steel plate. That is, the light reflecting portion 50 can be formed by providing a protective layer 35 and a photocatalytic layer 36 on the surface of a high light reflective coated steel plate. The light reflecting portion 50 can also be formed by providing a protective layer 35 and a photocatalytic layer 36 on the surface of a high light diffusion coated steel plate.

[0025] For example, the high light reflection type coated steel plate may be a product named "High Reflection Type Viewcoat" manufactured by Nippon Steel & Sumitomo Metal Corporation. In addition, the steel plate described in Patent No. 4074847 and Patent No. 4314080 may be used. The high light diffusion type coated steel plate can diffuse and reflect light emitted from the light source 3 more efficiently than the high light reflection type coated steel plate. Furthermore, since the illuminance can be kept high, the number of light sources 3 and the power consumption can be reduced, which may lead to total cost reduction and energy saving. For example, the high light diffusion type coated steel plate may have an illuminance of 40 to 45% higher than that of a general-purpose coated steel plate, and the power consumption can be reduced by 15 to 20% when the illuminance is 2000 lx (JIS Z 9110: Show Window Important Part Illuminance Standard) compared to the general-purpose coated steel plate. As the highly light-diffusing coated steel sheet, for example, a coated sheet proposed by the present applicant (see PCT / JP2016 / 001232) can be used.

[0026] The light reflecting portion 50 can be formed by forming a protective layer 35 on the surface of the high light reflection type coated steel plate or the high light diffusion type coated steel plate as described above, and further forming a photocatalyst layer 36 containing a photocatalyst on the surface of the protective layer 35. The photocatalyst layer 36 contains a photocatalyst such as titanium oxide. The photocatalyst is preferably a visible light excitation type, which makes the photocatalyst more likely to be activated by indoor light. In particular, it is preferable to use anatase type titanium oxide as the titanium oxide. The oxidative decomposition function of the photocatalyst improves the antibacterial, antifungal, antiviral, and air purification (gas decomposition) functions, and also provides a hydrophilic function on the surface. That is, when light hits the titanium oxide photocatalyst, active oxygen (strong oxidizing power) is generated on the surface. It is thought that this active oxygen decomposes organic matter, bacteria, and mold. For example, when the photocatalyst layer 36 is irradiated with white fluorescent light, the generation of Staphylococcus aureus and Penicillium is suppressed. Furthermore, when the photocatalyst layer 36 is irradiated with fluorescent light, the proliferation of influenza A virus is suppressed. As the photocatalyst layer 36, the one disclosed in Japanese Patent No. 4588164 or Japanese Patent Laid-Open No. 2006-272036 can be used.

[0027] The photocatalytic reaction occurs in the photocatalytic layer 36 twice: when light enters the photocatalytic layer 36 and passes through the photocatalytic layer 36, and when light is reflected by the topcoat coating layer 31 and passes through the photocatalytic layer 36 again. When a high light diffusion type coated steel plate is used, the amount of reflected light is as much as 85% of the incident light, so the oxidative decomposition function of the photocatalyst due to the reflected light is improved. On the other hand, in the case of a general-purpose coated steel plate, the amount of reflected light is attenuated to 5% to 70% of the incident light, so the photocatalytic reaction due to the reflected light is relatively weak. Furthermore, in the case of a high light diffusion type coated steel plate, the reflected light is diffused over a wide area, so the probability of the photocatalyst being excited is high. On the other hand, in the case of a general-purpose coated steel plate, the diffusion of the reflected light is small, so the probability of the photocatalyst being excited is relatively low. From the above, when the light reflecting portion 50 is formed using a high light diffusion type coated steel plate, the oxidative decomposition function of the photocatalyst is expressed earlier than when a general-purpose coated steel plate is used.

[0028] To describe the light reflecting portion 50 in more detail, the multilayer coating film 32 as described above can be formed on the surface of a substrate 33 such as a steel plate. A coated plate 34 provided with the multilayer coating film 32 as described above includes a substrate 33, and on the substrate 33, a primer layer 30, a topcoat coating film layer 31 on the primer layer 30, a protective layer 35 on the topcoat coating film layer 31, and a photocatalyst layer 36 on the protective layer 35.

[0029] The primer layer 30 contains a primer resin binder containing a polyester resin and a curing agent, and 80 parts by mass or more and 250 parts by mass or less of titanium oxide pigment (rutile type titanium oxide) based on 100 parts by mass of the primer resin binder, and the film thickness of the primer layer 30 is 10 μm or more and 20 μm or less.

[0030] Rutile titanium oxide has a high refractive index and therefore tends to reflect light at the white pigment-binder interface. Therefore, by including rutile titanium oxide as a white pigment in the primer layer 30, the light reflectance of the primer layer 30 can be improved. The rutile titanium oxide may be surface-treated with Al, Si, Zr, an organic substance, or the like. The primer layer 30 may include a commercially available rutile titanium oxide as a white pigment. Examples of commercially available rutile titanium oxide include the "Tipaque TM" series manufactured by Ishihara Sangyo Kaisha, Ltd. and the "Titanix" series manufactured by Teika Corporation. The primer layer 30 may include a white pigment other than rutile titanium oxide.

[0031] The average particle size of the white pigment contained in the primer layer 30 is preferably 200 nm or more and 400 nm or less. In this case, the surface area of ​​the white pigment can be increased, the reflectance of the primer layer 30 can be improved, and the transmittance of light on the long wavelength side can be prevented from increasing.

[0032] The topcoat coating layer 31 contains a topcoat resin binder containing a polyester resin and a hardener, and 100 to 250 parts by mass of titanium oxide pigment (rutile type titanium oxide) and 10 to 30 parts by mass of organic polymer fine particles having an average particle diameter of 4 to 9 μm, relative to 100 parts by mass of the topcoat resin binder, and the thickness of the topcoat coating layer 31 is 20 to 35 μm. The surface of the multilayer coating film 32 has a diffuse reflectance of 85% or more at a light wavelength of 550 nm.

[0033] Rutile-type titanium oxide has a higher refractive index than other pigments, and therefore it is possible to increase the difference in refractive index between rutile-type titanium oxide and the resin and air contained in the topcoat coating layer 31. By increasing this difference in refractive index, it is possible to increase the diffuse reflectance of the topcoat coating layer 31.

[0034] The rutile titanium oxide particles may be particles alone, or may be rutile titanium oxide particles coated with silica, alumina, zirconia, zinc oxide, antimony oxide, organic substances, etc. Examples of the organic substances used for coating may include polyols such as pentaerythritol and trimethylolpropane, alkanolamines such as triethanolamine and organic acid salts of trimethylolamine, silicone resins, and silicones such as alkylchlorosilanes.

[0035] The average particle size of rutile-type titanium oxide is preferably 200 nm or more and 400 nm or less. In this case, the reflectance of the topcoat coating layer 31 can be improved, and light that has passed through the photocatalyst layer 36 and reached the topcoat coating layer 31 can be easily reflected toward the photocatalyst layer 3. In addition, light of a wavelength that easily activates the photocatalyst contained in the photocatalyst layer 36 can be easily reflected by the topcoat coating layer 31. The average particle size of rutile-type titanium oxide is more preferably 250 nm or more and 350 nm or less. The average particle size of rutile-type titanium oxide is the arithmetic mean value of the particle sizes of the remaining rutile-type titanium oxides, which are obtained by observing the topcoat coating layer 31 at a magnification of 10,000 times with an electron microscope, and excluding the smallest 20% and the largest 5% of the rutile-type titanium oxides projected in the field of view.

[0036] The protective layer 35 is a coating film that makes it difficult for the action of the photocatalyst contained in the photocatalyst layer 36 to affect the topcoat coating film layer 31, and may contain organic polymers such as polyester, urethane, acrylic, and epoxy. Specific examples of polyester resins include polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, and polybutylene naphthalate. Urethane resins are polymer compounds in which monomers are copolymerized with urethane bonds formed by condensation of isocyanate groups and alcohol groups. Acrylic resins are polymers of acrylic acid esters or methacrylic acid esters, and are highly transparent amorphous synthetic resins. Epoxy resins are a general term for compounds having two or more oxirane rings (epoxy groups) in the molecule, and specific examples include bisphenol-type and novolac-type epoxy resins. The thickness of the protective layer 35 can usually be 5 μm or more and 50 μm or less.

[0037] The photocatalytic layer 36 contains anatase type titanium oxide. The anatase type titanium oxide may be doped with anions such as nitrogen or sulfur, may support Pt particles, or may be AgNbO 3 and SrTiO 3 Among them, anatase type titanium oxide crystals doped with nitrogen are preferably used because they can be produced inexpensively.

[0038] Examples of the binder (film component) of the photocatalyst layer 36 include silicon oxide and siloxane polymer. The silicon oxide is preferably amorphous silica. Specific examples of the siloxane polymer include a resin made of a dehydration condensate obtained by hydrolysis of a tetraalkoxysilane having an alkoxy group with 1 to 4 carbon atoms and an alkoxysilane having an epoxy group, followed by a condensation reaction.

[0039] The content of the photocatalyst (anatase-type titanium oxide) per unit area of ​​the photocatalyst layer 36 is 0.1 g / m 2 More than 2.0g / m 2In this case, the photoactivation effect of the photocatalyst layer 36 can be improved, and the performance (strength, etc.) of the photocatalyst layer 36 as a coating film can be prevented from being impaired.

[0040] By using such a coated plate 34, the ceiling portion 7 and the shelf portion 2 constituting the light reflecting portion 50 can be easily formed. The back portion 8 and the side wall portion 10 may be formed by the coated plate 34 having the multi-layer coating film 32 as described above. In this case, the coated plate 34 is arranged so that the multi-layer coating film 32 faces the shelf portion 2. As a result, the back portion 8 and the side wall portion 10 also have a light reflecting surface (second light reflecting surface) 90, and the light from the light source 3 can easily reach every corner of the upper surface of the shelf portion 2, making it easier to improve the photosynthetic photon flux density on the upper surface of the shelf portion 2. That is, when the back portion 8 and the side wall portion 10 are formed by using the coated plate 34, the inner surface of the back portion 8 (the surface facing the shelf portion 2) is formed as the light reflecting surface 90. Also, the inner surface of the side wall portion 10 (the surface facing the shelf portion 2) is formed as the light reflecting surface 90. Furthermore, if the multi-layer coating film 32 of the coating plate 34 used on the shelf 2, ceiling 7, back surface 8, and side wall 10 contains a photocatalyst, when the air around the shelf 2 comes into contact with the photocatalyst layer 36, bacteria, mold, and viruses contained in the air are easily decomposed and removed, making it harder for plants to get sick.

[0041] In this embodiment, the first light reflecting surface 9 has a light source 3 directly below it, and the second light reflecting surface 90 does not have a light source 3. The first light reflecting surface 9 and the second light reflecting surface 90 have approximately the same light reflectance.

[0042] As shown in Fig. 5, slits 11 are provided in the rear portion 8. The slits 11 are formed long in the horizontal direction and are formed so as to open to the inner surface (the surface on the shelf portion 2 side) and the outer surface of the rear portion 8. A plurality of slits 11 are formed so as to be lined up vertically. The slits 11 are provided corresponding to the spaces between the ceiling portion 7 and the uppermost shelf portion 2a, and between adjacent shelf portions 2 vertically. Air flows through the slits 11 to each shelf portion 2, thereby enabling temperature control, etc.

[0043] In the above-described cultivation shelf 1, plants are grown by placing them on the shelf portion 2 and turning on the light source 3. By turning on the light source 3, optimal light conditions for growing plants can be set, and plants can be grown efficiently.

[0044] The cultivation shelf 1 of this embodiment can further be provided with an auxiliary reflection member 5. The auxiliary reflection member 5 can be provided on the inside of the side wall portion 10 corresponding to each shelf portion 2. The auxiliary reflection member 5 can be formed of a painted plate 34 having the multi-layer coating film 32 as described above. The auxiliary reflection member 5 is a member that reflects light, similar to the light reflecting portion 50.

[0045] In the example shown in Fig. 6A, the light reflecting surface 90 of the auxiliary reflection member 5 is concavely curved, and as shown in Figs. 6B and 6C, the auxiliary reflection member 5 is provided so as to be concavely curved toward the shelf portion 2. In the example shown in Fig. 7A, the light reflecting surface 90 of the auxiliary reflection member 5 is convexly curved, and as shown in Figs. 7B and 7C, the auxiliary reflection member 5 is provided so as to be convexly curved toward the shelf portion 2. In the example shown in Fig. 8A, the auxiliary reflection member 5 has a protruding portion 52 from which the light reflecting surface 90 protrudes, and as shown in Figs. 8B and 8C, the protruding portion 52 protrudes toward the shelf portion 2, and the upper and lower mounting pieces 51, 53 are attached to the side surfaces of the upper and lower shelves 2 to provide the auxiliary reflection member 5. In the example shown in Figure 9A, the reflection auxiliary member 5 has an inclined surface 55 such that the light reflecting surface 90 is inclined downward, and as shown in Figures 9B and 9C, the inclined surface 55 protrudes toward the shelf portion 2, and the upper and lower mounting pieces 54, 56 are attached to the side surfaces of the upper and lower shelf portions 2 to provide the reflection auxiliary member 5.

[0046] By providing such an auxiliary reflection member 5, the amount of light supplied to the shelf portion 2 is increased, and plant growth can be improved. In particular, the ones in Figures 7A to C and Figures 8A to C are preferable as they increase the amount of light more than the ones in Figures 6A to C and Figures 9A to C.

[0047] Furthermore, it is preferable to provide an eave at the entrance 6 on the side of the light source 3 to reduce light leakage from the light source 3, thereby suppressing light loss due to light leakage. For example, if the height of the eave is set to 50 mm, light leakage can be reduced by about 3% compared to the case where no eave is provided.

[0048] The auxiliary reflection member 5 having the light reflecting surface 90 may be provided not only on the side of the shelf portion 2 but also on either the upper side or the rear side of the shelf portion 2 or both. EXAMPLES

[0049] The present invention will now be described in detail with reference to examples.

[0050] Example 1 A cultivation shelf 1 shown in Figures 1A to 1C was formed. The shelf portion 2, ceiling portion 7, back portion 8, and side wall portion 10 of this cultivation shelf 1 were formed from highly light-diffusing painted steel plate manufactured by Nippon Steel & Sumitomo Metal Corporation. The highly light-diffusing painted steel plate has a steel plate substrate and a multi-layer coating film on the substrate, which is composed of two layers: a primer layer and a topcoat coating film layer on the primer layer. This multi-layer coating film has a light-reflecting surface 9 formed as a light-diffusing surface, and the light-reflecting surface 9 had a diffuse reflectance of 85.2% at a light wavelength of 550 nm.

[0051] A 33 W fluorescent lamp was used as the light source 3. Five light sources 3 were provided on each light reflecting surface 9 of the ceiling portion 7 and the shelf portion 2. The gap between the light sources 3 and the light reflecting surface 9 was set to 5 mm.

[0052] Example 2 A cultivation shelf 1 was formed in the same manner as in Example 1, except that a 23 W LED was used as the light source 3 instead of a fluorescent lamp.

[0053] Comparative Example 1 The cultivation shelf 1 was formed in the same manner as in Example 1, except that the gap between the light source 3 and the light reflecting surface 9 was set to 35 mm.

[0054] Comparative Example 2 Except for using a plain coated steel plate instead of the highly light-diffusing coated steel plate, a cultivation shelf 1 was formed in the same manner as in Example 1. The plain coated steel plate had a diffuse reflectance of 52.5% at a light wavelength of 550 nm.

[0055] Comparative Example 3 Except for using an aluminum sheet instead of the highly light-diffusing painted steel plate, a cultivation shelf 1 was formed in the same manner as in Example 1. The aluminum sheet had a diffuse reflectance of 79.3% at a light wavelength of 550 nm.

[0056] Comparative Example 4 Except for using a white plastic cardboard plate instead of the highly light-diffusing painted steel plate, a cultivation shelf 1 was formed in the same manner as in Example 1. The white plastic cardboard plate had a diffuse reflectance of 80.5% at a light wavelength of 550 nm.

[0057] For each of the examples and comparative examples, the illuminance and photon flux density were measured on the upper surface of shelf portion 2. The results are shown in FIGS.

[0058] Since Examples 1 and 2 have a light reflecting surface 9 with high diffuse reflectance, the illuminance and photosynthetic photon flux density values ​​are higher than those of Comparative Examples 1 to 4. Since Example 1 has a light reflecting surface 9 directly above the light source 3, the illuminance and photosynthetic photon flux density values ​​are higher than those of Comparative Example 1.

[0059] The bacteria suppression effect was confirmed for a coated steel sheet having a photocatalyst layer and a coated steel sheet not having a photocatalyst layer as follows. The confirmation method is as follows. (1) Pre-culture of the strain The four types of bacteria (Bacillus aryabhattai, Aeromicrobium sp, Marmoricola sp, and Bacillus sp) were isolated and inoculated onto normal agar medium to restore the strains. These bacteria were collected from the plant factory. (2) Preparation of bacterial solution The fresh culture cultured in (1) above was suspended in physiological saline, and the bacterial concentration was measured using a hemocytometer to confirm that the bacterial concentration was 10 8The concentration was adjusted to approximately 1 / ml. (3) Bacteria liquid application process The dry heat sterilized steel plate was placed in a petri dish and 0.1 ml of the bacterial solution prepared in (2) was dropped onto it. A spatula was used to spread the bacterial solution over the entire steel plate, the petri dish was covered and a photograph was taken before exposure to light. The bacterial solution was applied to a total of two steel plates for each strain. The breakdown of the two plates is shown below. (A) With photocatalyst layer: A bacterial liquid was applied and then recovered after light irradiation, and the viable bacterial count was measured. (B) Without photocatalytic layer: The bacterial liquid was applied and left for the same period as in (A) without being irradiated with light, then the bacteria were collected and the viable bacterial count was measured. (4) Light irradiation process The petri dish was covered with a lid, and the illuminance was adjusted to a range of 1000 to 1500 Lx, followed by irradiation for 16 hours. (5) Bacterial liquid recovery process The bacterial liquid was collected using a sterile cotton swab, and the cotton swab that had absorbed the bacterial liquid was suspended in 1.9 ml of sterile saline (the collected liquid was now 20 times diluted). The method of wiping the steel plate with the cotton swab was standardized for all samples to avoid differences in the number of live bacteria collected. (6) Evaluation The suspension collected in (5) was inoculated onto a normal agar medium and incubated in an incubator at 30°C for 24 hours, after which the number of bacteria was counted (CFU count by dilution plate method). In addition, to increase the detection sensitivity, the number of bacteria was counted by the membrane filter method. The number of bacteria in (A) and (B) was calculated from the dilution ratio at the time of collection of the bacterial liquid. The results are shown in Table 1.

[0060] [Table 1]

[0061] As a result of testing four types of bacteria as described above, two of the four types of bacteria were almost completely killed on the coated steel plate with a photocatalyst layer. On the other hand, no inhibitory effect was observed on the coated steel plate without a photocatalyst layer. Therefore, it can be said that the antibacterial properties of the cultivation shelf are improved by forming a light reflecting part using a coated plate with a photocatalyst layer.

[0062] (summary) The first aspect is a cultivation shelf (10) that includes a shelf portion (2) for arranging plants and a light source (3) that emits light to irradiate the plants arranged on the shelf portion (2). A light reflecting portion (50) having a light reflectance of 85% or more is provided above the shelf portion (2). The light source (3) is provided directly below the light reflecting portion (50).

[0063] In this case, the light emitted from the light source (3) is more easily reflected by the light reflecting portion (50), which makes it easier to improve the amount of light required for growing plants on the shelf portion (2).

[0064] In the second aspect, in the first aspect, the light reflecting portion (50) has a coating layer with a titanium oxide content of 35% by mass or more and 85% by mass or less.

[0065] In this case, a light reflecting portion (50) having a light reflectance of 85% or more can be easily formed.

[0066] The third embodiment is the first or second embodiment, in which the photosynthetic photon flux density at the shelf portion (2) when the light source (3) emits light is 100 μmol m -2 s -1 More than 400 μmol m -2 s -1 The following is the result.

[0067] In this case, the light emitted from the light source (3) can promote the growth of plants placed on the shelf portion (2).

[0068] In the fourth embodiment, in the first to third embodiments, the light reflecting portion (50) includes a multi-layer coating film (32). The multi-layer coating film (32) has a primer layer (30) and a topcoat coating film layer (31) on the primer layer (30). The light source (3) is disposed on the surface of the multi-layer coating film (32).

[0069] In this case, the light source (3) can be disposed in contact with the multi-layer coating film (32), and the light reflectance of the light reflecting portion (50) is less likely to decrease.

[0070] In the fifth embodiment, in the first to fourth embodiments, a light reflecting surface (90) is provided on at least one of the upper, side and rear surfaces of the shelf portion (2).

[0071] In this case, light can be reflected and irradiated onto the shelf portion (2) from the light reflecting surfaces (90) on the upper, sides and back of the shelf portion (2), making it easier to ensure the amount of light necessary for plant growth.

[0072] In a sixth aspect, in the first to fifth aspects, the light reflecting portion (50) further includes a photocatalytic layer (36). The photocatalytic layer (36) contains anatase type titanium oxide.

[0073] In this case, the photocatalyst layer (36) can inactivate bacteria and viruses, thereby imparting antibacterial and antiviral properties. [Explanation of symbols]

[0074] 1 cultivation rack 2 Shelves 3 light source 30 Primer layer 31 Topcoat layer 32 Multi-layer coating 36 Photocatalyst layer 50 Light reflection part 90 Light reflective surface

Claims

1. A cultivation shelf including a shelf portion for arranging plants and a light source for emitting light for irradiating the plants arranged on the shelf portion, A light reflecting portion having a light reflectance of 85% or more is provided above the shelf portion, The light source is located directly below the light reflecting portion, The light reflecting portion is provided with a multi-layer coating film, and the multi-layer coating film constitutes a light reflecting surface having a light reflectance of 85% or more; The multi-layer coating film has a primer layer and a topcoat coating film layer on the primer layer, The light source is disposed in contact with a surface of the multi-layer coating film; The shelf further includes an entrance for inserting and removing plants, and a long slit is provided in the horizontal direction on the rear surface opposite to the entrance. Further comprising a light reflecting surface on a side of the shelf portion, the light reflecting surface is formed of a reflection assisting member provided corresponding to each of the plurality of shelf portions, The reflection auxiliary member is formed of a coated plate having the multi-layer coating film, The reflection assistant member has a protruding portion from which the light reflection surface protrudes, the protruding portion protruding toward the shelf portion, and upper and lower attachment pieces attached to side surfaces of the upper and lower shelf portions, A canopy is provided at the entrance on the side of the light source. Cultivation shelf.

2. In claim 1, The topcoat coating layer has a titanium oxide content of 35% by mass or more and 85% by mass or less. Cultivation shelf.

3. In claim 1 or 2, The photosynthetic photon flux density at the shelf when the light source is emitting light is 100 μmol m －２ s －１ More than 400 μmol －２ s －１ is less than or equal to Cultivation shelf.

4. In any one of claims 1 to 3, The light reflecting portion further includes a photocatalytic layer, The photocatalyst layer contains anatase type titanium oxide. Cultivation shelf.

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