WO2022071100A1 - Plant growing member and plant growing method - Google Patents

Abstract

A plant growing member according to the present invention comprises a laminated structure that has: a light non-transmitting resin substrate; and a wavelength converter formed on the light non-transmitting resin substrate and containing a fluorescent material.

Description

Plant growing materials and plant growing methods

The present invention relates to a plant growing member and a plant growing method.

Various developments have been made on plant growing methods. As this kind of technique, for example, the technique described in Patent Document 1 is known. Patent Document 1 describes a technique for irradiating the surface side of a plant leaf with a color converter having a translucent body having a phosphor on the surface or inside (claim 1). Item 1, FIGS. 1 to 3 etc.). FIG. 2 of Patent Document 1 shows a method for growing a plant by converting the wavelength of the input light emitted from the light source by a phosphor while passing through the translucent body and irradiating the surface side of the leaf of the plant. Has been done.

Japanese Unexamined Patent Publication No. 2008-181771

However, as a result of the study by the present inventor, it has been found that there is room for improvement in the ability of the color converter described in Patent Document 1 to promote the growth of plants by irradiating light from the back surface side of the leaves of the plants. ..

As a general plant growing method, there is a method of irradiating light from the surface side of the leaf. This is because most of the chloroplasts are present on the surface side of the leaves of the plant. The technique of Patent Document 1 is also classified into this method.

As a result of repeated studies on the method of growing plants using specific plant growth evaluation indexes such as the number of leaves, maximum leaf length, fresh weight of leaves, and dry weight, the present inventor also studied from the back surface side of the leaves. It was found that such a growth evaluation index was improved by irradiating with appropriate light, and a good effect of promoting plant growth was exhibited.

As a result of further diligent research based on such findings, a plant growing member having a laminated structure having a light-impermeable substrate and a wavelength converter was created in order to irradiate the back surface of the leaf with light. Then, at least a part of the light emitted from above the plant is converted to an appropriate leaf length by a plant growing member installed on the lower side of the leaf of the plant, reflected and scattered, and the leaves are reflected from below the plant. By irradiating the back surface of the plant with light, it was found that the ability to promote the growth of plants was improved, and the present invention was completed.

According to the present invention
A plant growing member comprising a laminated structure having a light-impermeable resin base material and a wavelength converter formed on the light-impermeable resin base material.
The wavelength converter is composed of a light-transmitting resin layer containing a phosphor and a polyurethane resin.
Members for growing plants are provided.

Further, according to the present invention.
The step of arranging the above-mentioned plant growing member below or to the side of the plant,
A step of irradiating the plant growing member with excitation light, and the like.
A method for growing plants is provided.

According to the present invention, there is provided a plant growing member having an excellent ability to promote plant growth by irradiating light from the back surface side of a plant leaf, and a plant growing method using the same.

It is a side schematic diagram schematically showing an example of the plant growing member of 1st Embodiment. (A) is a side schematic view schematically showing an example of a plant growing member of the second embodiment, and (b) is a top surface schematic view thereof. It is a figure which shows the outline of the optical path in the case of (a) a light reflection layer (specular reflection layer), and (b) the light path in the case of a light scattering layer. It is a figure which shows the excitation / emission spectrum of (a) CaAl ₁₂ O ₁₉ : Mn ⁴⁺ , and (b) the excitation / emission spectrum of CaAl ₄ O ₇ : Mn ⁴⁺ . (A) Wavelength-dependent spectrum of plant photosynthesis efficiency and CaAl ₁₂ O ₁₉ : Mn ⁴⁺ emission spectrum superimposed, (b) Wavelength-dependent spectrum of plant photosynthesis efficiency and CaAl ₄ O ₇ : Mn ⁴⁺ . It is the figure which overlapped with the emission spectrum of. It is the figure which superposed the spectrum of the wavelength dependence of the plant photosynthesis efficiency, and the emission spectrum of CaAlSiN ₃ : Eu ²⁺ . It is a top view schematically showing an example of the modification of the plant growing member of this embodiment. (A) A side schematic view schematically showing an example of a modification of the plant growing member of the present embodiment, and (b) a top surface schematic view thereof. It is a figure which shows the result of the spectroscopic spectrum of Example 1 and Comparative Example 1. It is a figure which shows the arrangement drawing of the member for plant growth.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all drawings, similar components are designated by the same reference numerals, and description thereof will be omitted as appropriate. Further, the figure is a schematic view and does not match the actual dimensional ratio.
In this embodiment, the front-back, left-right, up-down directions are defined and described as shown in the figure. However, this is provided for convenience in order to briefly explain the relative relationships of the components. Therefore, it does not limit the direction in which the product according to the present invention is manufactured or used.

The outline of the plant growing member of this embodiment will be described.

The plant growing member of the first embodiment includes a laminated structure having a light-impermeable resin base material and a wavelength converter formed on the light-impermeable resin base material. This wavelength converter is composed of a light-transmitting resin layer containing a phosphor.

According to the findings of the present inventor, by appropriately irradiating the back surface of leaves with appropriate light, growth evaluation indexes such as the number of leaves, maximum leaf length, fresh weight of leaves, and dry weight are improved, and good plant growth is promoted. It was found that the effect was obtained.

The plant growing member is used to irradiate the back surface of the leaf with light.
Install plant growing members on the side or bottom of the plant. For example, a plant growing member may be installed on the ground such as the soil where the plant is cultivated.

When light is emitted from the upper side of the plant from a light source such as sunlight or lighting, a part of the light is reflected by the plant growing member and is emitted toward the back surface of the leaf of the plant. Then, the light is converted into an appropriate wavelength by the wavelength converter in the plant growing member, and the light is diffusely reflected or scattered by the light opaque substrate made of resin.
As described above, the plant growing member can irradiate the back surface of the leaf with light having an appropriate wavelength diffused or scattered, so that the ability to promote the growing of the plant can be enhanced.

Further, the plant growing member of the second embodiment has a structure in which a laminated structure having a light-impermeable base material and a wavelength converter is sealed with a light-transmitting encapsulant.

According to the knowledge of the present inventor, durability may be required for the plant growing member. For example, durability is required not only indoors but also outdoors, when used while supplying liquid fertilizer or water to plants, or when used in a relatively high humidity environment.

As a result of further studies based on such circumstances, it was found that the durability against moisture and dirt can be improved by sealing the laminated structure with a light-transmitting encapsulant. Further, since the encapsulant is made of an appropriate light-transmitting material, the above-mentioned ability to promote plant growth can be maintained.

Hereinafter, each configuration of the plant growing member of the present embodiment will be described.

FIG. 1 is a side schematic diagram schematically showing an example of a plant growing member of the first embodiment. FIG. 2A is a side schematic view schematically showing an example of the plant growing member of the second embodiment, and FIG. 2B is a top surface schematic view. FIG. 2A is a cross-sectional view taken along the line AA of FIG. 2B.

The plant growing member 100 of the first embodiment is formed on a light impermeable resin base material (light impermeable base material 10 made of resin) and a light impermeable resin base material, and is a phosphor. The laminated structure 50 including the wavelength converter 20 including the above is provided.

The plant growing member 110 of the second embodiment may include a light transmitting sealing body 30 that seals the laminated structure 50. The plant growing member 110 is laminated with a laminated structure 50 having a light opaque base material 10 and a wavelength converter 20 formed on the light opaque base material 10 and containing a phosphor. A light transmissive sealing body 30 for sealing the structure 50 is provided.

The light-impermeable base material 10 is not limited as long as it reflects light without transmitting it, and reflects light effective for photosynthesis of plants. The reflected light includes sunlight, illumination light, excitation light of a phosphor, and the like.

The light impermeable base material 10 may have a mechanical strength sufficient to be used as a member.

The shape of the light-impermeable base material 10 is not particularly limited, but it may be in the form of a sheet, or may have a curved structure or a bent structure in a part thereof.

The sheet-shaped light impermeable base material 10 may be composed of a single layer, or may be composed of a plurality of layers. The plurality of layers may be made of the same material, or at least a part of the layers may be made of different materials.

The lower limit of the thickness of the light opaque substrate 10 is, for example, 0.01 mm or more, preferably 0.1 mm or more, and more preferably 0.3 mm or more. Thereby, the mechanical strength can be increased. On the other hand, the upper limit of the thickness of the light-impermeable substrate 10 is, for example, 10 mm or less, preferably 5 mm or less, and more preferably 3 mm or less. This makes it possible to reduce the weight and the manufacturing cost.

The light-impermeable base material 10 may be composed of one or more selected from the group consisting of a resin material, a paper material, and an inorganic material. In the first embodiment, a light impermeable base material 10 (light impermeable resin base material) made of a resin material is used, and in the second embodiment, a group consisting of a resin material, a paper material, and an inorganic material. A light impermeable base material 10 composed of one or more selected from the above may be used.

The light-impermeable base material 10 made of resin may be composed of a resin material containing at least one selected from the group consisting of Teflon, polyethylene, polyester, polypropylene, and polyvinyl chloride. These may be used alone or in combination of two or more. The resin material may contain various additives, if necessary.

Among the resin materials, a material showing white color may be shown from the viewpoint of light reflection effective for photosynthesis. That is, the light-impermeable base material 10 made of resin may be made of white resin. As the white resin, a resin in which the resin itself is white or a resin in which a white pigment or a white dye is mixed is used. Specific examples of the white resin include Teflon and the like.

The light-impermeable base material 10 made of a sheet-shaped resin may be made of a white resin sheet. The white resin sheet may have one layer or may be composed of a plurality of layers.

The light-impermeable base material 10 may have a light-reflecting layer on the surface or inside. The light reflecting layer may be a light scattering layer or a specular reflecting layer. Here, the light scattering layer may include a layer that scatters light or a layer that diffusely reflects light.

The light scattering layer is configured by appropriately selecting a resin material, a paper material, and an inorganic material. A fine uneven structure may be formed on the surface of the light-impermeable base material 10 by surface treatment. As the paper material, for example, blank paper may be used.
The specular reflection layer is formed of a mirror plate using a known inorganic material.

The light-impermeable base material 10 preferably has a light scattering layer as a light-reflecting layer from the viewpoint of promoting plant growth.

Red light and blue light are generally known as light colors effective for photosynthesis of plants.
These lights are included in the light emitted from a light source used for growing plants, such as sunlight and illumination light.

According to the findings of the present inventor, the ability to promote plant growth can be further enhanced when red light or blue light is diffusely reflected or scattered rather than specularly reflected by the light opaque substrate 10. There was found.

FIG. 3A is a diagram showing an outline of an optical path when the light-impermeable base material 10 includes a light-reflecting layer (specular reflection layer), and FIG. 3B is a view showing an outline of a light-transmitting base material. 10 is a diagram showing an outline of an optical path when 10 includes a light scattering layer.

Since red light is more effective for photosynthesis than blue light, the phosphor contained in the wavelength converter 20 uses a red phosphor that emits red light, and the phosphor contained in the wavelength converter 20 does not use a blue phosphor. A configuration example was examined.

The red phosphor is excited by the light emitted from the light source, and the red light is emitted from the red phosphor. Since the light emitted from the phosphor is highly dispersed, it is possible to enhance the plant growing ability.

On the other hand, the blue light contained in the light emitted from the light source is mirror-reflected without being dispersed by the mirror-reflecting layer of FIG. .. That is, only a part of the blue light contained in the light source can be used for growing plants.

On the other hand, the blue light contained in the light emitted from the light source is dispersed (scattered or diffusely reflected) by the light scattering layer of FIG. 3 (b), so that the reflection direction is not limited and the plant is affected. More light is emitted. That is, as compared with the case of the specular reflection layer of FIG. 3A, much of the blue light contained in the light source can be used for growing plants.

Therefore, the light opaque base material 10 made of resin in FIG. 1 and the light opaque base material 10 in FIG. 2 include a light scattering layer to emit light emitted from a phosphor and light contained in a light source. Since it can be diffused, many of the light components that can be used for growing plants can be used more effectively.
Therefore, the plant growing members 100 and 110 of the present embodiment can exhibit good plant growing promoting ability.

The wavelength converter 20 is provided on at least one of the main surface and the back surface of the sheet-shaped light opaque substrate 10. The wavelength converter 20 may be provided on both the main surface and the back surface.

The wavelength converter 20 may be formed on at least a part of the surface of the main surface or the back surface of the light opaque substrate 10, or the wavelength converter 20 may be formed on the entire surface thereof. One or two or more wavelength converters 20 may be formed in the plane of the surface of the light opaque substrate 10.

Of the surface of the light opaque substrate 10, the surface provided with the wavelength converter 20 may be formed of a flat surface or a part thereof may be formed of an uneven surface.

The wavelength converter 20 may be in close contact with the surface of the light impermeable base material 10 via an intermediate layer such as an adhesive layer, or may be in direct contact with the surface. The intermediate layer may be composed of a transparent material. From the viewpoint of luminous flux efficiency, a laminated structure 50 in which the wavelength converter 20 and the light opaque substrate 10 are directly bonded may be adopted.

The wavelength converter 20 contains a phosphor inside or on the surface. The phosphor may be in the form of a sheet or in the form of particles.

The phosphor is not particularly limited as long as it emits light that can be used for growing plants, but may include a red phosphor that emits red light.

As the red phosphor, a visible light excitable red phosphor having an excitation peak intensity in the visible light region may be used.
The red phosphor excited only by ultraviolet light is not sufficiently excited by the photons of sunlight having a wide wavelength from near-ultraviolet to visible light, and there is a possibility that sufficient red light cannot be emitted under sunlight. On the other hand, the red phosphor that can be excited by visible light is sufficiently excited in a wide range of wavelengths. Therefore, the ability to promote plant growth can be further enhanced.

The red phosphor may contain one or more selected from the group consisting of oxide phosphors, nitride phosphors, sulfide phosphors, and fluoride phosphors. Among these, one or more selected from the group consisting of oxide phosphors and nitride phosphors is preferable. This makes it possible to increase the durability of the plant growing member when it is used for a long time or when a large amount of fluorescent material is used. Oxide fluorophores are excellent in cost, and nitride phosphors are excellent in intensity.

The red phosphor may contain one or more selected from the group consisting of Mn and Eu as the activating element, but may also contain inexpensive Mn. From the viewpoint of durability and manufacturing cost, the red phosphor may contain an oxide phosphor containing the activating element Mn, and specifically, an oxide phosphor activating Mn ^{4+ (Mn 4+ activated} oxide fluorescence). Body) may be included.
The red phosphor composed of the oxide phosphor may contain CaTIO ₃ : Pr ³⁺ .

The Mn ⁴⁺ activated oxide phosphor may contain an element having a large Clarke number. This makes it possible to stably manufacture a large-area plant growing member. Specifically, the Mn ⁴⁺ activated oxide phosphor may contain Ca, Al, and Mn.

According to the findings of the present inventor, the Mn ⁴⁺ activated oxide phosphor containing Ca, Al, and Mn can excite visible light and bring about the maximum photosynthetic rate of plants in the wavelength range of 600 nm to 700 nm. It was found that a red phosphor having an emission peak can be realized only.

The red phosphor may contain a manganese-activated calcium-aluminate-based red phosphor as the Mn ^{4 +} activated oxide phosphor containing Ca, Al, and Mn. The manganese-activated calcium aluminate-based red fluorescent substance is represented by the chemical formula of CaAl ₁₂ O ₁₉ : a phosphor represented by Mn ⁴⁺ corresponding to the CA phase and CaAl ₄ O ₇ : Mn ⁴⁺ corresponding to the CA ₂ phase. It may contain one or more fluorescent substances selected from the group consisting of the above-mentioned fluorescent substances.

FIG. 4A shows the excitation / emission spectrum of CaAl ₁₂ O ₁₉ : Mn ⁴⁺ , and FIG. 4B shows the excitation / emission spectrum of CaAl ₄ O ₇ : Mn ⁴⁺ .
FIG. 5A shows a diagram in which the wavelength-dependent spectrum of plant photosynthesis efficiency and the emission spectrum of CaAl ₁₂ O ₁₉ : Mn ⁴⁺ are superimposed, and FIG. 5B shows the wavelength of plant photosynthesis efficiency. The figure which superposed the spectrum of the dependence and the emission spectrum of CaAl ₄ O ₇ : Mn ⁴⁺ is shown. In FIGS. 5-6, the thick line shows the wavelength-dependent spectrum and the thin line shows the emission spectrum.

For comparison, FIG. 6 shows a superposed diagram of the wavelength-dependent spectrum of plant photosynthesis efficiency and the emission spectrum of CaAlSiN ₃ : Eu ²⁺ . CaAlSiN ₃ : Eu ²⁺ is a typical example of a europium-activated nitride fluorophore that emits visible light-excited red light.

As shown in FIG. 6, the peak of red emission emitted from CaAlSiN ₃ : Eu ²⁺ , which is a nitride phosphor, has a wide range and extends beyond the wavelength region of 600 nm to 700 nm, which is the highest efficiency of photosynthesis. Therefore, even if the red light of CaAlSiN ₃ : Eu ²⁺ is used, it may not be sufficiently enhanced to improve the photosynthesis efficiency.

On the other hand, as shown in FIGS. 5 (a) and 5 (b), the range of the red emission peaks of CaAl ₁₂ O ₁₉ : Mn ⁴⁺ and CaAl ₄ O ₇ : Mn ⁴⁺ is in the region of the highest photosynthetic efficiency. .. Therefore, by using CaAl ₁₂ O ₁₉ : Mn ⁴⁺ and / or CaAl ₄ O ₇ : Mn ⁴⁺ , the photosynthesis efficiency can be sufficiently improved.

However, when the red phosphor is a nitride phosphor, (Ca, Sr) AlSiN ₃ : Eu or (Sr, Ba) ₂ Si ₅ N ₈ : Eu is relatively preferable because it can increase the red luminous flux. For (Ca, Sr) AlSiN ₃ : Eu and (Sr, Ba) ₂ Si ₅ N ₈ : Eu, for example, strontium nitride, calcium nitride, silicon nitride, aluminum nitride, europium nitride, and barium salt are mixed and fired. Obtained by

In CaAl ₁₂ O ₁₉ : Mn ⁴⁺ and CaAl ₄ O ₇ : Mn ⁴⁺ , the molar ratio of Mn ⁴⁺ to Ca is, for example, 0.002 to 0.4, preferably 0.005 to 0.1. In either case, different elements may be substituted within a range of 3 mol% with respect to Ca within a range in which the excitation / emission characteristics do not change significantly.

In the method for producing a red phosphor such as CaAl ₁₂ O ₁₉ : Mn ⁴⁺ and CaAl ₄ O ₇ : Mn ⁴⁺ , organic acid salts such as manganese and aluminum carbonates, oxides, nitrates, halides and oxalates are used. Can be used as a raw material. For calcium, similar compounds other than carbonate can be used as raw materials. Carbonates, oxides, and nitrates can be used from the viewpoint of ease of handling and versatility of decomposition products during firing.

For mixing the raw materials, a normal method can be used in which the raw material powder can be sufficiently and evenly mixed after being crushed using a dry crusher such as a hammer mill, a roll mill, a ball mill, or a jet mill.

Examples of the mixing method include a method using a dispersed medium such as a ball mill, a pearl mill, and a vibrating ball mill, a method using gravity such as a V-type blender, and a method using a mixer having a stirring blade such as a ribbon blender and a Henshell mixer. Can be mentioned.

The mixture of raw materials may be calcined under air, nitrogen, or a gas in which oxygen and nitrogen are mixed at an appropriate ratio, for example, in the range of 1200 ° C to 1500 ° C. It may be fired under pressurized or reduced pressure gas, but it is preferable to fire under normal pressure gas because it is convenient. The firing time is, for example, 1 hour to 12 hours, more preferably 2 hours to 6 hours. The composite after firing may be lightly pulverized. The pulverization may be performed so that the average particle size is 0.1 μm or more and 20 μm or less.

(Ca, Sr) AlSiN ₃ : The Sr / (Ca + Sr) molar ratio in Eu is usually 0 to 1, but from the viewpoint of emission wavelength promoting plant growth and stability, 0 to 0.8 is more suitable. Preferably, 0 to 0.3 is even more preferable, and 0 is most preferable.

From the viewpoint of the red luminous flux that promotes plant growth and economic efficiency, the molar ratio of Eu to Al is preferably 0.004 to 0.02, more preferably 0.01 to 0.2.

(Ca, Sr) In the method for producing Eu 2 ⁺ activated red inorganic phosphor (emission peak wavelength: 600 nm to 700 nm) such as AlSiN ₃ : Eu, calcium, strontium, aluminum, silicon nitride, metal, or alloy is used as a raw material. Is preferable.

For mixing raw materials, it is preferable to use a hammer mill, roll mill, ball mill, jet mill, pearl mill, vibration ball mill, V-type blender, ribbon blender, Henschel mixer, or the like.

When firing the mixture of raw materials, the apparatus is preferably a resistance heating type vacuum pressurized atmosphere heat treatment furnace, a normal pressure atmosphere furnace, a hot or the like pressure device (HIP), or the like. The firing gas is preferably high-purity nitrogen gas, hydrogen-containing nitrogen gas, ammonia or the like. The firing temperature is preferably 1450 ° C. or higher and 1900 ° C. or lower. The firing time is preferably 1 hour to 24 hours, more preferably 2 hours to 8 hours. The composite after firing may be lightly pulverized. The pulverization may be performed so that the average particle size is 0.1 μm or more and 20 μm or less. The average particle size is preferably a value of 50% diameter (D50) in a volume-based integrated fraction obtained by measuring the particle size distribution by a laser diffraction / scattering method using a particle size distribution measuring device.

The fluorescent substance may contain a fluorescent substance other than the red fluorescent substance, and may include, for example, a blue fluorescent substance that emits blue light. These may be used alone or in combination of two or more.

From the viewpoint of adjusting the wavelength distribution of light given to plants, a small amount of a luminescent substance having a luminescent color other than the red phosphor may be added.

The wavelength converter 20 may include a phosphorescent material in addition to the phosphor. The phosphorescent material absorbs and stores the light when it is irradiated, and continues to emit light for a predetermined time even after the light irradiation is stopped, for example, at night. The phosphorescent material has an afterglow persistence of about several minutes to several tens of hours after the completion of photoexcitation.

By using a phosphorescent material, it is possible to promote the growth of plants by emitting the light necessary for growing plants, preferably red light, even at night by the phosphorescence during the day.

The phosphorescent material may contain a phosphorescent material that emits red light, but may also contain a phosphorescent material that emits excitation light of a phosphor.

A red phosphorescent body may be used as the phosphorescent material that emits red light.
This red phosphor is excited only by ultraviolet light, and can generate only faint red light during the daytime and at night when it is exposed to sunlight.

As a result of the study by the present inventor in consideration of such circumstances, it has been found that the phosphor and the phosphorescent material that emits the excitation light of the phosphor are used in combination. Specific examples include a combination of a visible light-excited red phosphor and a blue-yellow-green phosphorescent material.
As the blue to yellow-green phosphorescent material, Eu, Dy-activated strontium aluminate, which exhibits high phosphorescent intensity, can be used.

During the daytime, the visible light-excited red phosphor emits red light, and Eu, Dy-activated strontium aluminate stores the ultraviolet light of sunlight. At night, the energy stored by Eu, Dy-activated strontium aluminate is emitted as blue to yellow-green light. A visible light-excited red phosphor existing in the vicinity of the phosphorescent material can emit red light by using its emission as excitation light. Therefore, even at night, the relatively strong red light can promote the growth of plants.
The Eu, Dy-activated strontium aluminate is preferably at least one selected from the group consisting of green to yellowish green SrAl ₂ O ₄ : Eu, Dy or blue Sr ₄ Al ₁₄ O ₂₅ : Eu, Dy. The molar ratio of Eu, Dy-activated strontium aluminate used to the visible light-excited fluorophore is preferably 0.3 to 40, more preferably 1 to 20.

The wavelength converter 20 includes a plurality of phosphor particles and a light-transmitting resin layer. A plurality of phosphor particles are dispersed inside the light-transmitting resin layer. Such a wavelength converter 20 can suppress variations in light emission characteristics due to the phosphor throughout. Since the light-transmitting resin layer is made of resin, it is easy to handle.

As the resin material constituting the light-transmitting resin layer, a material having excellent processability and / or weather resistance as well as transparency can be used, and examples thereof include polyurethane resin.

The transparency of the resin constituting the light-transmitting resin layer means, for example, that the lower limit of the maximum transmittance is, for example, 50% or more, preferably 70% or more, in the wavelength region of 400 nm or more and 700 nm or less, which is visible light. It means that it is preferably 90% or more. The upper limit of the maximum transmittance is not particularly limited, but may be 100% or less.

The polyurethane resin is, for example, a polymer obtained by a polymerization reaction between a polyol compound containing two or more hydroxyl groups in the molecule and an isocyanate compound containing an isocyanate group in the molecule. As the diol compound and the isocyanate compound, one or more known compounds can be used, respectively.
From the viewpoint of enhancing the light resistance to ultraviolet light, at least one of the diol compound and the isocyanate compound may have an alicyclic structure in the molecule.

As the polyol compound, a polycarbonate polyol is preferable. As the polyol compound, a diol compound is preferable. As the polycarbonate polyol, polycarbonate diol is preferable. As the polycarbonate diol, a condensate of glycol and diethyl carbonate is preferable. As the glycol, for example, 3-methyl-1,5-pentanediol and 1,6-hexamethylenediol are used, and the mass ratio is 3-methyl-1,5-pentanediol: 1,6-hexamethylenediol =. It is preferably contained so as to be 50:50 to 90:10. The number average molecular weight of glycol is preferably 500 to 2,000.

The number average molecular weight is, for example, a number average molecular weight in terms of polyethylene glycol, and is measured by GPC (gel permeation chromatography). For example, the number average molecular weight is determined by using water as a solvent, using a GPC system (SC-8010 manufactured by Tosoh Corporation), and preparing a calibration curve with commercially available standard polyethylene glycol.

As the isocyanate compound, a polyisocyanate compound is preferable. As the polyisocyanate compound, an aliphatic polyisocyanate is preferable. As the aliphatic polyisocyanate, for example, polyisocyanurate based on HDI (hexamethylene diisocyanate) is preferable. Examples of the polyisocyanate include nurate, allophanate, burette, adduct and the like.

The polyurethane resin may contain one or more additives such as a catalyst, a dispersant, a film-forming auxiliary, a thickener, an antifoaming agent, and an ultraviolet absorber as long as the effects of the present invention are not impaired. good.

The elongation rate of the polyurethane resin is, for example, 50% to 1500%, preferably 100% to 1200%. The elongation rate is based on JIS A 602 and means the elongation at break measured under the condition of 23 ° C.
Since such a polyurethane resin has excellent extensibility and flexibility as compared with an epoxy resin having an elongation rate of usually 2 to 10%, the processability of the excellent plant growing members 100 and 110 is improved. can. The term "workability" as used herein means that the member is less likely to be damaged and that the member is easily bent and / or cut.

The thickness of the light-transmitting resin layer is, for example, 0.05 mm to 5 mm, preferably 0.1 mm to 3 mm, and more preferably 0.8 mm to 2 mm.

An example of the light-transmitting resin layer may be configured to contain a resin having an elongation rate of 50% to 1500%.
An example of the light-transmitting resin layer may be configured to contain a polyurethane resin, or may be configured to contain a polyurethane resin as a main component. The main component means that the content of the polyurethane resin is, for example, 50% by mass or more, preferably 80% by mass or more, and more preferably 90% by mass or more in 100% by mass of the light-transmitting resin layer.

The light-transmitting resin layer may be composed of a single layer or multiple layers, or may be configured to include at least a polyurethane resin layer. The layer other than the polyurethane resin layer may be a layer containing, for example, an epoxy resin, a silicone resin, a vinyl resin, or the like.

The content of the phosphor in the wavelength converter 20 is not particularly limited in 100% by mass of the light transmissive resin layer made of the resin material, but is, for example, 0.1% by mass or more and 40% by mass or less, preferably 0. It may be 3% by mass or more and 8% by mass or less.

The molding method of the wavelength converter 20 is not particularly limited, and known methods such as extrusion molding using a roll, compression press molding, cast molding, and molding method using a mold can be appropriately adopted.

The plant growing members 100 and 110 may be in the form of a sheet, or may have a curved or bent structure in part.

The shape of the sheet can be multi-film or plate, and can be arranged according to the application. In particular, the plate-shaped one can be installed directly under the first leaf of the plant, and the installation location and installation angle can be adjusted according to the growing condition of the plant.

The plant growing members 100 and 110 may be configured to be self-supporting. This makes it easier to handle during installation. The plant growing members 100 and 110 may be placed flat on the ground, or may be installed with a part thereof pierced into the soil.

The lower limit of the thickness of the plant growing members 100 and 110 is, for example, 0.1 mm or more, preferably 0.5 mm or more, and more preferably 1 mm or more. As a result, the mechanical strength can be increased. On the other hand, the upper limit of the thickness of the plant growing members 100 and 110 is, for example, 10 mm or less, preferably 5 mm or less, and more preferably 3 mm or less. This makes it possible to reduce the weight and the manufacturing cost.

The plant growing member 110 of FIGS. 2A and 2B includes a light transmitting encapsulating body 30.
The light transmissive sealing body 30 may be configured to cover at least a part of the laminated structure 50, may be configured to cover the surface or side surface of the wavelength converter 20, and is the main of the laminated structure 50. The entire surface, side surface, and back surface may be covered. As a result, the durability and handleability of the plant growing member 110 can be improved.

The light-transmitting encapsulant 30 is not particularly limited as long as it is made of a transparent material that transmits light necessary for growing plants, excitation light of a fluorescent substance, or light emission from the fluorescent substance. The light transmissive encapsulant 30 may contain one or more selected from the group consisting of polyethylene, polyester, polypropylene, and polyvinyl chloride.

As a method for molding the light-transmitting encapsulant 30, a coating method, a film laminating method, or the like using a transparent material may be used. Heat / pressure treatment may be applied at the time of molding.

When the laminated structure 50 is viewed from the laminated direction, the plant growing member 110 may have a margin portion 32 formed of the light transmissive sealing body 30 formed around the laminated structure 50. Since the side surface of the laminated structure 50 is protected by the margin portion 32, the long-term durability of the plant growing member 110 can be enhanced.

When the laminated structure 50 is viewed from the laminated direction, the plant growing member 110 has a structure in which all the ends located around the laminated structure 50 are covered with the light transmissive sealing body 30. May be good. As a result, it is possible to prevent water from entering from the end portion, so that the waterproof property can be improved.

Further, the margin portion 32 can be processed into various shapes according to the purpose.

FIGS. 7 (a) and 7 (b) show a modified example of the second embodiment. 7 (a) and 7 (b) are top views schematically showing an example of a plant growing member 114 and a plant growing member 116.

The plant growing member 114 may have a notch 36 formed in the margin portion 32 of the light transmissive sealing body 30. The plant may be placed in the recess formed by the notch 36. As a result, the plant growing member 114 is spread over the area where the plant is cultivated. Alternatively, a plurality of plant growing members 114 may be connected by combining the concave portion and the convex portion formed by the notch portion 36.

The plant growing member 116 may have a notch 38 having a shape capable of piercing the soil in the margin portion 32 of the light transmissive sealing body 30. As a result, the plant growing member 116 can be stably installed in the soil while maintaining a predetermined angle.

8 (a) and 8 (b) show other modified examples of the second embodiment. FIG. 8A is a side view schematically showing an example of the plant growing member 112, and FIG. 8B is a top view thereof. FIG. 8A is a cross-sectional view taken along the line BB.

When the laminated structure 50 is viewed from the laminated direction, the plant growing member 112 is provided with a plurality of laminated structures 50 in the in-plane direction orthogonal to the laminated direction, and the laminated structure 50 is provided between the adjacent laminated structures 50. It has a structure in which a separation portion 34 composed of a light-transmitting sealing body 30 is formed.

The plant growing member 112 may have a plurality of laminated structures 50 arranged in the in-plane direction. The laminated structure 50 can be appropriately arranged depending on the purpose such as the cultivation position of the plant.

Since the side surface of the plurality of laminated structures 50 is covered with the separating portion 34, the durability of the plant growing member 112 can be enhanced. Further, the light transmissive encapsulant 30 may be formed of a material that is more flexible than the light transmissive base material 10. Thereby, the shape of the plant growing member 112 can be deformed by the separating portion 34.

In the top view of the plant growing member 112, the pattern of the separating portion 34 is not particularly limited, but may extend in the vertical, horizontal, and diagonal directions, or these may intersect. A plurality of patterns of the separation portion 34 may be formed in each direction.

The separating portion 34 may be made of a material that can be cut.
Thereby, when it is desired to increase the strength of the light-impermeable base material 10, the separation portion 34 can be cut, the plant growing member 112 can be processed into an appropriate size and shape, and can be installed in the soil. At the plant cultivation site, the plant growing member 112 can be processed into an appropriate shape.

The plant growing member of the present embodiment can be suitably used for growing plants.
The plant growing method includes a step of arranging the above-mentioned plant growing member below or to the side of the plant, and a step of irradiating the plant growing member with excitation light.

The plant is not particularly limited, but may be a plant having leaves or an agricultural plant.

According to this embodiment, it is possible to promote the growth of plants.

Although the embodiments of the present invention have been described above, these are examples of the present invention, and various configurations other than the above can be adopted. Further, the present invention is not limited to the above-described embodiment, and modifications and improvements within the range in which the object of the present invention can be achieved are included in the present invention.

Hereinafter, the present invention will be described in detail with reference to Examples, but the present invention is not limited to the description of these Examples.

<Creation of plant growing materials>
(Example 1)
A _{transparent polyurethane} resin ₉ . 84 g was added, a kneading device (ARV-310, manufactured by Shinky Co., Ltd.) was introduced, and the mixture was vacuum defoamed and stirred under the conditions of a rotation speed of 1000 rpm, a pressure of 0.7 Pa, and a stirring time of 3 minutes to obtain a mixture. The transparent polyurethane resin is 100 parts by mass of polycarbonate diol (Nipporan 965, manufactured by Tosoh), 100 parts by mass of aliphatic polyisocyanate (Coronate HX / Coronate 2770 = 7/3 (mass ratio), manufactured by Tosoh), and bells. A mixture of 0.08 parts by mass of a catalyst (Neostan U-810) was used. The resulting mixture was placed in a mold placed on a white tephron coat and cured at 25 ° C. overnight.
Here, Nipponporan 965 is a polycarbonate diol obtained by condensing glycol composed of 3-methyl-1,5-pentanediol: 1,6-hexamethylenediol = 90:10 (mass ratio) and diethyl carbonate, and the number thereof. The average molecular weight is 1,000. Coronate HX is a nurate, which is a trimer of hexamethylene diisocyanate. Coronate 2770 is an allophanate made from 1,6-hexamethylene diisocyanate and monoalcohol. Ca _0.99 Eu _0.01 AlSiN ₃ was obtained by mixing calcium nitride, silicon nitride, aluminum nitride and europium nitride and firing.
A plant growing plant in which a red fluorescent film containing a red fluorescent substance having a thickness of 1 mm and 1.6% by mass was formed on a white Teflon sheet having a thickness of 0.3 mm, a length of 28 cm, and a width of 28 cm by removing the horizontal frame of the mold. The member e was obtained.

(Comparative Example 1)
As the plant growing member d containing no fluorescent substance, a white Teflon sheet having a thickness of 0.3 mm, a length of 28 cm, and a width of 28 cm was used as it was.

The plant growing members of each of the obtained Examples and Comparative Examples were evaluated based on the following evaluation items.

(Spectroscopic spectrum)
In a dark room, the surface of the red phosphor film of the plant growing member e (Example 1) and the surface of the plant growing member d (Comparative Example 1) white teflon sheet are each at a distance of 35 cm from the surface with respect to the surface. The xenon lamp light was irradiated in the vertical direction under the condition of an intensity of 0.4 mW / cm ² . The spectral spectra of the light from each surface of Example 1 and Comparative Example 1 were measured using a spectrophotometer.
CL-500A manufactured by Konica Minolta Co., Ltd. is used as the spectroscopic measuring instrument, the angle between the light receiving axis of the measuring instrument and each surface is set to 60 degrees diagonally upward, and the distance from the surface center to the measuring instrument is 16 cm. The spectroscopic spectrum was measured.
The results of the spectral spectrum are shown in FIG. In the plant growing member e of Example 1, the luminous flux in the near-ultraviolet, blue, and green regions is significantly reduced, and the luminous flux in the red region is significantly increased, as compared with the plant growing member d of Comparative Example 1. The results are shown.

(Plant test)
The plant growing member e of Example 1 and the plant growing member d of Comparative Example 1 were divided into four parts, and four sheets of 28 cm × 7 cm were prepared respectively.
As a plant, 5 strains of Komatsuna (variety: Rakuten) were sown in the soil at intervals such as in a row. Ten days after sowing, a sheet (plant growing member) divided into four was placed on the soil surface so as to sandwich the Japanese mustard spinach. FIG. 10 shows a layout drawing of the plant growing member. FIG. 10A shows a diagram in which the plant growing member is arranged so that the back surface of the Komatsuna leaf is irradiated with the light reflected by the surface of the plant growing member.
After arranging the plant growing members, Komatsuna was grown for 2 weeks under the test conditions of the following cultivation tests 1 to 3. The cultivated Japanese mustard spinach is shown in FIG. 10 (b).

・ Cultivation test 1
Test conditions: Outdoor vinyl greenhouse Light intensity (photon flux density): 1,000 to 1,500 μmolm ^-2 s ^-1
・ Cultivation test 2
Test conditions: Artificial meteorological machine (25 ° C, 6 hours day length)
Amount of light (photon flux density): 151 μmolm ^-2 s ^-1
・ Cultivation test 3
Test conditions: Artificial meteorological machine (25 ° C, 12 hours day length)
Amount of light (photon flux density): 29 μmolm ^-2 s ^-1

After that, the above-ground part of Komatsuna was harvested. The number of true leaves (sheets) in the above-ground part harvested, the maximum leaf length (cm) in the leaves, the mass of the leaves in the above-ground part harvested (fresh mass of the above-ground part before drying, g), and the leaves are dried at a constant rate of 105 ° C. The mass of the leaves after drying by the method (dry mass on the ground, g) was measured, and the chlorophyll content (SPAD value) contained in the leaves was measured using SPAD-502Plus manufactured by Konica Minolta. Regarding the evaluation results of Komatsuna, Table 1 shows 5 strains, Table 2 shows 4 strains, and Table 3 shows the mean value (Mean) and standard deviation (SD) based on the measured values of 4 strains.
For comparison, the above plant tests (cultivation tests 1 to 3) were carried out without arranging the plant growing members (control).

In all of Example 1, Comparative Example 1 and the control, the chlorophyll content contained in the leaves of the plant was about the same within the experimental error range, but by using the plant growing member e of Example 1. It was shown that an excellent plant growth promoting effect can be obtained as compared with the case where the plant growth member is not used (control) or the plant growth member d is used (Comparative Example 1).

(Example 2)
A light-transmitting polypropylene film having a thickness of 0.2 mm, a length of 30 cm, and a width of 30 cm was heat-laminated on both sides of the plant growing member e obtained in Example 1, and a white Teflon sheet and a white Teflon sheet were formed by the upper and lower polypropylene films. The red phosphor film was sealed to obtain a plant growing member h (Example 2).
The plant growing member h of Example 2 was excellent in waterproofness and durability during repeated use. The margin portion of the polypropylene film provided around the white tephron coat can be easily processed, so that it is easy to handle.
In addition, each of the plant growing members h of Example 2 showed the same level of plant growth promoting effect as the plant growing member e of Example 1.
When a manganese-activated calcium-aluminate-based red fluorescent substance was used as the red fluorescent substance, it showed an effect of promoting plant growth.

By irradiating light of an appropriate wavelength from the back side of the leaves using the plant growing members of Examples 1 and 2 as described above, it becomes possible to grow plants more efficiently and productively. In addition, it is more effective under conditions of weak light such as in cloudy weather or on the Sea of Japan side in winter.

This application claims priority on the basis of Japanese Application Japanese Patent Application No. 2020-163369 filed on September 29, 2020, and incorporates all of its disclosures herein.

10 Light-impermeable base material 20 Wavelength converter 30 Light-transmitting encapsulant 32 Margin part 34 Separation part 36 Notch part 38 Notch part 50 Laminated structure 100 Plant growing member 110 Plant growing member 112 For plant growing Member 114 Plant growing member 116 Plant growing member

Claims (16)

1. A plant growing member comprising a laminated structure having a light-impermeable resin base material and a wavelength converter formed on the light-impermeable resin base material.
   The wavelength converter is composed of a light-transmitting resin layer containing a phosphor and a polyurethane resin.
   A member for growing plants.
2. The plant growing member according to claim 1.
   A plant growing member comprising one or more selected from the group consisting of Teflon, polyethylene, polyester, polypropylene, and polyvinyl chloride as the light-impermeable resin base material.
3. The plant growing member according to claim 1 or 2.
   A member for growing a plant, wherein the light-impermeable resin base material includes a light-scattering layer.
4. The plant growing member according to any one of claims 1 to 3.
   The light-impermeable resin base material is a plant growing member composed of a white resin sheet.
5. The plant growing member according to any one of claims 1 to 4.
   A plant growing member having a light-impermeable resin base material having a thickness of 0.01 mm or more and 10 mm or less.
6. The plant growing member according to any one of claims 1 to 5.
   A member for growing a plant, wherein the fluorescent substance contains a red fluorescent substance.
7. The plant growing member according to claim 6.
   A member for growing a plant, wherein the red fluorescent substance contains at least one selected from the group consisting of manganese and europium as activating elements.
8. The plant growing member according to claim 6 or 7.
   A plant growing member comprising one or more selected from the group consisting of a manganese-activated calcium aluminate-based red fluorescent substance and CaAlSiN ₃ : Eu ²⁺ .
9. The plant growing member according to any one of claims 1 to 8.
   The wavelength converter is a plant growing member containing a phosphorescent material.
10. The plant growing member according to claim 9.
    The phosphorescent material is a plant growing member including a material that emits the excitation light of the phosphor.
11. The plant growing member according to any one of claims 1 to 10.
    A member for growing plants that is configured to be self-supporting.
12. The plant growing member according to any one of claims 1 to 11.
    A plant growing member used to irradiate the back surface of plant leaves with light.
13. The plant growing member according to any one of claims 1 to 12.
    A plant growing member comprising a light-transmitting sealant that seals the laminated structure.
14. The plant growing member according to claim 13.
    The light transmissive encapsulant comprises one or more selected from the group consisting of polyethylene, polyester, polypropylene, and polyvinyl chloride.
    A member for growing plants.
15. The plant growing member according to claim 13 or 14.
    A plant growing member having a margin portion formed of a light-transmitting encapsulating body formed around the laminated structure when the laminated structure is viewed from the stacking direction.
16. The step of arranging the plant growing member according to any one of claims 1 to 15 below or to the side of the plant.
    A step of irradiating the plant growing member with excitation light, and the like.
    How to grow plants.

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