Photon upconversion porous body, method for producing the same, light irradiation method, and flow channel for light irradiation

Abstract

To provide a photon upconversion material that is applicable to flow systems and has broad applicability.SOLUTION: A photon upconversion porous body of the present invention comprises a framework including a donor and an acceptor, and has through-holes, where the hole diameter is, for example, 0.1-100 μm.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a photon upconversion porous body useful as a source of ultraviolet light generation, a method for producing the same, and a light irradiation method and a flow path for light irradiation using a photon upconversion porous body. [Background technology]

[0002] Photon upconversion (UC) is a technology that converts low-energy light into high-energy light, and has attracted attention as an energy creation technology that can improve the efficiency of solar-powered devices, including solar cells, organic photoreactions, and artificial photosynthesis. A photon upconversion composition that combines a donor that functions as a triplet sensitizer and an acceptor that functions as an emitter is known as a material system that drives photon upconversion. In this composition, when the donor is excited to an excited singlet state by irradiation with excitation light, it undergoes intersystem crossing to an excited triplet state, and the triplet energy is transferred to the acceptor. In the acceptor that has received energy and become an excited triplet state, the triplets between the two molecules meet and triplet-triplet annihilation (TTA) occurs, and one of the molecules transitions to an excited singlet state with higher energy than the excited triplet state and emits light (photon upconversion emission). In this composition, the irradiated light can be converted to light with higher energy (light with a shorter wavelength) by such photon upconversion by triplet-triplet annihilation (TTA-UC). Regarding these photon upconversion compositions, development is underway to improve the upconversion efficiency, and among these, there is research on porous photon upconversion materials.

[0003] For example, Non-Patent Document 1 and Patent Document 1 propose a photon upconversion porous film in which an O / W emulsion of a toluene solution of Pd-tetraphenyltetraanthraporphyrin (sensitizing component) and rubrene (light-emitting component) and an aqueous polyvinyl alcohol solution is applied to a substrate, dried, and then peeled off to generate bubbles. In this porous film, the sensitizing component and the light-emitting component are present at the interface between the polymer skeleton (matrix) and the voids, and it is said that upconversion light is generated by the upconversion mechanism of these components. [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] ACS Macro Lett. 2023, 12, 523-529 [Patent documents]

[0005] [Patent Document 1] International Publication No. 2023 / 074040 Summary of the Invention [Problem to be solved by the invention]

[0006] As described above, Non-Patent Document 1 and Patent Document 1 describe a photon upconversion porous film. In this photon upconversion porous film, the emulsion particles compressed in the dried coating film are pseudo-foamed by the external force applied in the peeling process to generate bubbles (voids), and the voids are formed by independent bubbles or by the merging of multiple bubbles. Since such porous films with bubbles have low fluid permeability, they cannot be applied to flow systems in which a porous body is placed in a flow path to allow the fluid to pass through, and there is a problem that the range of application is limited. Under these circumstances, the present inventors have carried out intensive research with the aim of providing a photon upconversion material that can be used in a flow system and has a wide range of applications. [Means for solving the problem]

[0007] As a result of intensive research to solve the above problems, the present inventors have found that by forming a photon upconversion material into a shape with through holes, a photon upconversion porous body that can be used in a flow system and has a wide range of applications can be realized. The present invention has been proposed based on this knowledge, and specifically has the following configuration.

[0008] [1] A photon upconversion porous material with a framework containing donors and acceptors and through-holes. [2] The photon upconversion porous body according to [1], wherein the through-pore diameter of the porous body is 0.1 to 100 μm. [3] The photon upconversion porous body according to [1] or [2], wherein the donor is dispersed in the acceptor. [4] The photon upconversion porous body according to [1] or [2], wherein the donor is present on the surface of the framework. [5] The photon upconversion porous body according to [1] or [2], further comprising a matrix resin in the skeleton portion. [6] The photon upconversion porous body according to [5], wherein the acceptor is dispersed in the matrix resin. [7] The photon upconversion porous body according to [6], wherein the donor is further dispersed in the matrix resin. [8] The photon upconversion porous body according to any one of [1] to [7], wherein the framework is monolithic. [9] The photon upconversion porous material according to any one of [1] to [8], which absorbs visible light and emits ultraviolet light.

[10] The photon upconversion porous body according to [9], which emits ultraviolet light having a wavelength of 280 to 320 nm.

[11] A light irradiation method comprising irradiating a photon upconversion porous body described in any one of [1] to

[10] with light and irradiating the resulting photon upconversion light onto a substance present in the through-holes.

[12] The light irradiation method according to

[11] , wherein the substance is supplied into the through-holes from outside the photon upconversion porous body.

[13] The light irradiation method according to

[11] or

[12] , wherein the photon upconversion porous body is irradiated with light while a fluid containing the substance is passed through the photon upconversion porous body.

[14] A flow path for light irradiation, in which the photon upconversion porous body according to any one of [1] to

[10] is disposed in a flow path for a substance-containing fluid to flow.

[15] A method for producing a photon upconversion porous body having a skeleton containing a donor and an acceptor and through holes, the method comprising the steps of filling a porous mold having through holes with a fluid containing the donor and the acceptor, solidifying the fluid, and then dissolving and removing the porous mold to form the skeleton.

[16] The method according to

[15] , wherein the fluid further contains a monomer, and the solidification is carried out by polymerizing the monomer.

[17] A method for producing a photon upconversion porous body having a skeleton containing a donor and an acceptor and through holes, the method comprising the steps of filling a porous mold having through holes with a fluid containing the acceptor, solidifying the fluid and then dissolving and removing the porous mold, and attaching the donor to the surface of the resulting porous body to form the skeleton.

[18] A method for producing a photon upconversion porous body having a framework containing a donor and an acceptor and through-holes, comprising the steps of: The production method is characterized by preparing a solution in which the donor, the acceptor, a monomer and a polymerization initiator are dissolved in two or more solvents, polymerizing the monomer to cause phase separation into a solid phase having the skeleton and a liquid phase, and removing the liquid phase. Effect of the Invention

[0009] The photon upconversion porous body of the present invention can also be applied to a flow system. Therefore, the photon upconversion porous body of the present invention enables UC light irradiation in a flow system in various fields that utilize UC light, such as photochemical reactions. According to the light irradiation method of the present invention, the UC light emitted by the photon upconversion porous body can be efficiently irradiated onto a substance. According to the light irradiation flow path of the present invention, the UC light emitted by the photon upconversion porous body can be efficiently irradiated onto a substance in a flow system. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a diagram for explaining the UC light emission mechanism of the photon upconversion porous body of the present invention. [Diagram 2] 1 is a SEM photograph of a porous silica monolith produced in an example. [Diagram 3] 1 is a perspective view showing a manufacturing process of Example 1. FIG. [Figure 4] 1 is an SEM photograph of a UC porous body 1 produced in Example 1. [Diagram 5] 1 shows UC emission spectra measured for UC porous body 1 while changing the excitation light intensity. [Figure 6] FIG. 11 is a perspective view showing a manufacturing process of the second embodiment. [Figure 7] 1 is a SEM photograph of a porous body of compound A2 prepared in Example 2. [Figure 8] 1 is a SEM photograph of a UC porous body 2 produced in Example 2. [Figure 9] 1 shows UC emission spectra measured for UC porous body 2 while changing the excitation light intensity. [Figure 10] FIG. 11 is a perspective view showing a manufacturing process of the third embodiment. [Figure 11] 1 is a SEM photograph of the porous body produced in Example 3. [Figure 12] 1 shows UC emission spectra measured for the UC porous body 3 while changing the excitation light intensity. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] The present invention will be described in detail below. The following description of the constituent elements may be based on a representative embodiment or specific example, but the present invention is not limited to such an embodiment. In this specification, a numerical range expressed using "to" means a range including the numerical values ​​before and after "to" as the lower and upper limits. In addition, the isotope species of hydrogen atoms present in the molecules of the compound used in the present invention are not particularly limited, and for example, all hydrogen atoms in the molecule may be 1 H, or part or all of 2 It may also be H (Deuterium D). In this specification, "visible light" means light having a wavelength in the range of more than 400 nm and not more than 800 nm, and "ultraviolet light" means light having a wavelength in the range of 200 nm to 400 nm. In addition, in this specification, ultraviolet light having a wavelength of 280 to 320 nm is referred to as "UVB light," and ultraviolet light having a wavelength of 320 to 400 nm is referred to as "UVA light."

[0012] <Photon upconversion porous material> The photon upconversion porous body of the present invention has a framework containing a donor and an acceptor, and through-holes. The "photon upconversion porous body" in the present invention means a porous body that absorbs light supplied to the porous body and emits light of a shorter wavelength. As a result, the "photon upconversion porous body" in the present invention shows the function of converting light supplied to the porous body into light of a shorter wavelength. The "porous body" in the "photon upconversion porous body" in the present invention means a solid having a skeleton (matrix) surrounding pores and through-holes. In this specification, the outer surface of the overall shape of the porous body is referred to as the "outer surface", and the surface surrounding the through-holes of the skeleton and other pores (the inner surface of the porous body) may be referred to as the "inner surface". In the photon upconversion porous body of the present invention, the original light converted into "shorter wavelength light" is light whose wavelength overlaps with the wavelength region (absorption wavelength region) in which the photon upconversion porous body exhibits optical absorption, specifically, light whose wavelength overlaps with the wavelength region (absorption wavelength region) in which the donor described below exhibits optical absorption. This original light is preferably light in a wavelength region longer than the ultraviolet light region, and more preferably visible light. In addition, the "shorter wavelength light" to be converted is preferably ultraviolet light. The original light and the converted light may be light with a single maximum emission wavelength, or may be composite light containing multiple lights with different maximum emission wavelengths. In a preferred embodiment of the present invention, the photon upconversion porous body is a porous body that absorbs visible light and emits ultraviolet light. In a preferred embodiment of the present invention, the photon upconversion porous body is a porous body that absorbs visible light and emits UVB light. The UVB light is light having a wavelength of 280 to 320 nm, and may be light having a wavelength of, for example, 280 to 315 nm. Here, UVB light is light that does not pass through ordinary glass. Therefore, when the photon upconversion porous body that emits UVB light is placed in a glass container to form a UC light-emitting element, it is not necessary to take measures such as covering the glass with a shielding material to prevent the emitted UVB light from leaking out. Therefore, the photon upconversion porous body that emits UVB light is highly practical.

[0013] In this specification, the light absorbed by a photon upconversion porous body is converted to light with a shorter wavelength and emitted as such is referred to as "photon upconversion luminescence" or "UC luminescence", the light emitted by photon upconversion luminescence (light with a shorter wavelength than the irradiated light) is referred to as "UC light", and the conversion efficiency of light irradiated onto a photon upconversion porous body to UC light is referred to as "upconversion efficiency" or "UC efficiency".

[0014] The "photon upconversion porous body" of the present invention contains at least a donor and an acceptor in the framework. Here, the "donor" absorbs light supplied to the composition, becomes excited, and provides the energy of the excited triplet state to the acceptor. The "acceptor" receives energy from the donor in the excited triplet state, causes photon upconversion by triplet-triplet annihilation (TTA-UC), and emits photon upconversion light (UC emission) by radiative deactivation from the excited singlet state thus generated. The mechanism of this UC emission will be explained with reference to FIG. 1. Here, the acceptor is excited at its lowest excited singlet energy level S 1,A is the lowest excited singlet energy level of the donor, S 1,D higher than its lowest excited triplet energy level T 1,A is the lowest excited triplet energy level of the donor, T 1,D In the present invention, the lowest excited triplet energy level T 1,A is the lowest excited triplet energy level of the donor, T 1,D It can function even when the optical wavelength is higher than 100 nm. In FIG. 1, the light supplied to the composition is excitation light for the donor, that is, light whose wavelength overlaps with the absorption wavelength range of the donor. In FIG. 1, "ISC" indicates intersystem crossing, "TET" indicates triplet energy transfer from the donor to the acceptor, and "TTA" indicates triplet-triplet annihilation. First, when excitation light is irradiated onto a photon upconversion porous material containing a donor and an acceptor, the donor molecule absorbs the light and transitions to an excited singlet state (S 1,D ), which then undergoes intersystem crossing to the excited triplet state (T 1,D The energy of the donor molecule in the excited triplet state is transferred to the acceptor molecule. This results in a transition to the excited triplet state (T 1,A ), the two triplets of the acceptor meet and triplet-triplet annihilation occurs, and one of the triplets enters an excited singlet state (S 1,A ) in the excited singlet state. In other words, photon upconversion occurs due to triplet-triplet annihilation of the acceptor molecule. The acceptor molecule thus reaches an excited singlet state, emitting fluorescence (UC light) and becoming inactivated, causing the composition to emit UC light. At this time, the excited singlet state (S 1,A ) has a very high energy level, so UC light with higher energy (shorter wavelength) than the excitation light can be obtained by radiative deactivation from its excited singlet state. Here, the luminescence obtained from the porous material is photon upconversion luminescence due to triplet-triplet annihilation, and the lifetime of the photon upconversion luminescence is about 10 ms. -1 This can be confirmed by the fact that the delayed fluorescence is on the order of milliseconds, and that the slope of the log-log plot of the photon upconversion luminescence intensity as a function of excitation light intensity changes from 2 to 1.

[0015] The skeleton and through-holes of the photon up-conversion porous body of the present invention will be specifically described below. In the following description, unless otherwise specified, the terms "alkyl group", "alkoxy group" and "aryl group" are substituents within the ranges shown below. The "alkyl group" may be linear, branched, or cyclic. The number of carbon atoms is preferably 1 to 20, more preferably 1 to 10, and further preferably 1 to 6. Specific examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, and an isopropyl group, but the "alkyl group" is not limited to these specific examples. At least one hydrogen atom of the alkyl group may be substituted with a substituent. The "alkoxy group" may be either linear or branched. The number of carbon atoms is preferably 1 to 20, more preferably 1 to 10, and further preferably 1 to 6. Specific examples of the alkoxy group include a methoxy group, an ethoxy group, an n-propoxy group, and an isopropoxy group, but the "alkoxy group" is not limited to these specific examples. At least one hydrogen atom of the alkoxy group may be substituted with a substituent. The "aryl group" may be composed of a monocyclic aromatic ring, a condensed ring in which two or more aromatic rings are condensed, or a linked ring in which two or more aromatic rings are linked. When two or more aromatic rings are linked, they may be linked in a straight chain or in a branched chain. The number of carbon atoms in the aromatic ring constituting the aryl group is preferably 6 to 22, more preferably 6 to 18, even more preferably 6 to 14, and even more preferably 6 to 10. Specific examples of the aryl group include a phenyl group, a naphthalenyl group, and a biphenyl group, but the "aryl group" is not limited to these specific examples. At least one hydrogen atom of the aryl group may be substituted with a substituent.

[0016] [Skeletal] The "skeleton" of the photon upconversion porous body of the present invention is the part other than the pores of the porous body, and contains at least a donor and an acceptor. The donor and the acceptor may be uniformly present in the skeleton, or may be localized in a specific region of the skeleton. The donor and acceptor are not particularly limited as long as they act on the above-mentioned UC luminescence mechanism. For example, the donors and acceptors shown below can be used.

[0017] [donor] The donor used in the present invention is preferably a compound that satisfies the following condition (A), and more preferably a compound that satisfies all of the following conditions (A) to (C). (A) The lowest excited singlet energy level S of the acceptor 1,A The lowest excited singlet energy level S 1,D and the lowest excited triplet energy level of the acceptor, T 1,A The lowest excited triplet energy level T 1,D To have. (B) High absorbance. (C) The absorbance is low at least in the ultraviolet region that overlaps with the wavelength region of UC light. The molecules of compounds that satisfy condition (A) have the lowest excited singlet energy level S of the acceptor. 1,A The lowest excited singlet energy level S 1,D By having this property, it is possible to excite the molecule to the singlet state using irradiation light with a wavelength longer than that of UC light. In addition, the molecule of the compound that satisfies condition (A) has the lowest excited triplet energy level T 1,A The lowest excited triplet energy level T 1,D Therefore, by using a compound that satisfies condition (A) as a donor, the UC emission mechanism shown in Figure 1 can function more reliably. The lowest excited singlet energy level of the acceptor, S 1,A and the lowest excited singlet energy level S of the donor 1,D The difference (S 1,A -S 1,D ) is preferably 0.3 to 2 eV, more preferably 0.4 to 1 eV, and further preferably 0.4 to 0.8 eV. The lowest excited triplet energy level of the donor, T1,D and the lowest excited triplet energy level T of the acceptor 1,A The difference (T 1,D -T 1,A ) is preferably 0.01 to 1 eV, more preferably 0.01 to 0.5 eV, and further preferably 0.01 to 0.2 eV. The lowest excited singlet energy level S 1,A , S 1,D and the lowest excited triplet energy level T 1,A , T 1,D The measurement method for the lowest excited singlet energy level S is described below. 1 and the lowest excited triplet energy level T 1 The energy levels can also be calculated by density functional theory. In addition, compounds that satisfy condition (A) as well as conditions (B) and (C) can efficiently absorb irradiated light while not absorbing UC light. Therefore, by using such compounds as donors, the threshold excitation intensity I th The threshold excitation intensity I th " is the excitation light intensity at the inflection point of a double logarithmic graph showing the dependence of UC emission intensity on the excitation light intensity. The lower this value, the lower the excitation light intensity required for UC emission, in other words, the more efficiently UC emission occurs. In condition (B), "high absorbance" means an absorption coefficient of 50,000M -1 cm -1 This means that it is more than or equal to this. In condition (C), "low absorbance" means an absorbance coefficient of 40,000M -1 cm -1 This means that:

[0018] The donor may be, for example, a compound having a coumarin skeleton (a coumarin compound). An example of the coumarin compound that may be used as the donor is a compound represented by the following general formula (1).

[0019] [ka]

[0020] In the general formula (1), R 1 ~R 6 R each independently represents a hydrogen atom or a substituent. 1 ~R 6 may be the same or different from each other. R 1 ~R 5 Examples of the substituent that may be taken by the group include a halogen atom (e.g., a fluorine atom, a chlorine atom, a bromine atom, an iodine atom), a halogenated alkyl group (e.g., a trifluoromethyl group), a halogenated aryl group (e.g., a bromophenyl group), a primary amino group, a secondary amino group (e.g., an alkylamino group, an arylamino group), a tertiary amino group (e.g., a dialkylamino group, a diarylamino group, an alkylarylamino group), a thiocarbonyl group, a hydroxyl group, an alkyl group, a cyano group, an imine group, a benzothiazole group, a benzoxazole group, a benzimidazole group, a furan group, a pyrrole group, a thiophene group, an oxazole group, an imidazole group, and a thiazole group. R 6 Examples of the substituent that can be taken by include a halogen atom (for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom), an alkoxy group, an alkyl group, an amino group, an alkylamino group, a phenylamino group, a pyridyl group, and a hydroxyl group. R 1 and R 2 , R 2 and R 3 , R 3 and R 4 , R 4 and R 5may be bonded to each other to form a ring. The ring may be an aromatic ring or an alicyclic ring. Examples of the ring include a benzene ring, a polycyclic aromatic ring formed by condensing two or more benzene rings (e.g., a naphthalene ring, an anthracene ring), a cyclohexadiene ring, a cyclohexene ring, a cyclopentaene ring, a dihydrofuran ring, a heterocycle (e.g., a furan ring, a pyrrole ring, a thiophene ring, an oxazole ring, an imidazole ring, a thiazole ring, a benzothiazole ring, a benzoxazole ring, a benzimidazole ring, a piperidine ring, a pyrrolidine ring, and a ring formed by condensing two or more of these), and a BODIPY ring (boron-dipyrromethene ring). For details and specific examples of the compound represented by general formula (1), WO2023 / 037848A1

[0028] to

[0030] can be referred to.

[0021] Specific examples of donors that can be used in the present invention include compounds containing heavy metals, as shown below. [ka] JPEG2025036025000003.jpg225170JPEG2025036025000004.jpg123169

[0022] Specific examples of donors that can be used in the present invention include the following heavy metal-free compounds. [ka] JPEG2025036025000006.jpg66170

[0023] [Acceptor] The acceptor of the photon upconversion composition used in the present invention is preferably a compound that satisfies the following condition (D). (D) The lowest excited singlet energy level of the donor, S 1,D The lowest excited singlet energy level S is higher than 1,A and the lowest excited triplet energy level of the donor, T 1,DThe lowest excited triplet energy level T 1,A To have. An acceptor molecule that satisfies condition (D) has the lowest excited singlet energy level S of the donor. 1,D The lowest excited singlet energy level S is higher than 1,A By having this property, it is possible to emit UC light with a shorter wavelength than the excitation light of the donor. In addition, an acceptor molecule that satisfies condition (D) has the lowest excited triplet energy level T of the donor. 1,D The lowest excited triplet energy level T 1,A Therefore, by using a compound that satisfies condition (D) as an acceptor, the UC emission mechanism shown in Figure 1 can function more reliably. The lowest excited singlet energy level of the acceptor, S 1,A and the lowest excited singlet energy level S of the donor 1,D The difference (S 1,A -S 1,D ) is preferably 0.3 to 2 eV, more preferably 0.4 to 1 eV, and further preferably 0.4 to 0.8 eV. The lowest excited triplet energy level of the donor, T 1,D and the lowest excited triplet energy level T of the acceptor 1,A The difference (T 1,D -T 1,A ) is preferably 0.01 to 1 eV, more preferably 0.01 to 0.5 eV, and further preferably 0.01 to 0.2 eV. The lowest excited singlet energy level S 1,A , S 1,D and the lowest excited triplet energy level T 1,A , T 1,D The measurement method for the lowest excited singlet energy level S is described below. 1 and the lowest excited triplet energy level T 1 The energy levels can also be calculated by density functional theory.

[0024] As the acceptor, a compound having a condensed ring in which an aromatic ring and a heterocycle are condensed (however, the total number of rings present in the molecule of the compound is 2 to 5, and the molecule of the compound does not contain a coumarin ring) or a substituted polycyclic aromatic hydrocarbon compound can be used. In the following description, a "compound having a condensed ring in which an aromatic ring and a heterocycle are condensed (however, the total number of rings present in the molecule of the compound is 2 to 5, and the molecule of the compound does not contain a coumarin ring)" may be referred to as a "polycyclic aromatic hetero compound". In addition, the "substituted polycyclic aromatic hydrocarbon compound" referred to here means a polycyclic aromatic hydrocarbon compound in which at least one hydrogen atom is substituted with a substituent, and the substituent substituted in the polycyclic structure in which the benzene ring is condensed is not limited to a hydrocarbon. A substituted naphthalene compound or a substituted pyrene compound is preferable. The photon upconversion composition may contain one or more compounds selected from the group of compounds consisting of polycyclic aromatic hetero compounds and substituted polycyclic aromatic hydrocarbon compounds as an acceptor. However, in one embodiment of the present invention, the acceptor is a compound other than a naphthalene compound substituted with a substituent containing at least one selected from the group consisting of an alkynyl group, a substituted silyl group, a benzene ring, a heteroaromatic ring, a cyano group, and a halogen atom.

[0025] In the fused ring of the polycyclic aromatic hetero compound used as the acceptor, at least one hydrogen atom may be substituted with a substituent. When the substituent of the fused ring contains a ring, the "total number of rings" in the above "total number of rings present in the compound molecule is 2 to 5" refers to the sum of the total number of rings constituting the fused ring and the total number of rings contained in the substituent. For example, in the case of the following compound shown as a specific example of a polycyclic aromatic hetero compound in the following column, the total number of rings is 5.

[0026] [ka]

[0027] The aromatic ring constituting the condensed ring of the polycyclic aromatic hetero compound may be an aromatic ring (aromatic hydrocarbon ring) consisting of carbon atoms and hydrogen atoms, or may be an aromatic ring (aromatic heterocycle) containing a heteroatom. An example of the aromatic hydrocarbon ring is a benzene ring. Examples of the heteroatom constituting the aromatic heterocycle include a nitrogen atom, an oxygen atom, and a sulfur atom, and a nitrogen atom is preferable. The aromatic heterocycle may contain one or more heteroatoms. When the aromatic heterocycle contains two or more heteroatoms, the heteroatoms may be the same or different. A preferred example of the aromatic heterocycle is a nitrogen-containing aromatic heterocycle having 5 or 6 ring members, 1 to 3 of which are nitrogen atoms, and a more preferred example is a nitrogen-containing aromatic heterocycle having 6 ring members, 1 to 3 of which are nitrogen atoms. Specific examples of the aromatic heterocycle include a pyridine ring, a pyridazine ring, a pyrimidine ring, a pyrazine ring, and a triazine ring. The heterocycle constituting the condensed ring of the polycyclic aromatic heterocycle may be an aromatic heterocycle or an alicyclic heterocycle. Examples of heteroatoms constituting the heterocycle include a nitrogen atom, an oxygen atom, a sulfur atom, and a cerium atom. The heterocycle may contain one or more heteroatoms. When the heterocycle contains two or more heteroatoms, the heteroatoms may be the same or different. The heterocycle preferably has 5 or 6 ring members, and 1 to 3 of the ring members are heteroatoms. Specific examples of the heterocycle include a pyrrole ring, a pyrroline ring, a pyrazole ring, an imidazole ring, a triazole ring, a pyridine ring, a pyridazine ring, a pyrimidine ring, a pyrazine ring, a triazine ring, a thiophene ring, a 2,3-dihydrodiphene ring, a furan ring, a 2,3-dihydrofuran ring, a 1,3-dioxole ring, a 2,3-dihydro-1,4-dioxine ring, an oxazole ring, an isoxazole ring, an oxadiazole ring, a thiazole ring, an isothiazole ring, a thiadiazole ring, and a selenadiazole ring. The number of rings constituting the condensed ring may be any one of 2 to 5, and is preferably 2 or 3. Specific examples of the fused rings constituting the polycyclic aromatic hetero compound are shown below, but the polycyclic aromatic hetero compound that can be used as the acceptor in the present invention is not limited to those having these fused rings.

[0028] [ka]

[0029] As described above, at least one hydrogen atom of the fused ring constituting the polycyclic aromatic hetero compound or at least one hydrogen atom of the fused ring constituting the polycyclic aromatic hydrocarbon compound may be substituted with a substituent. The substituent is not particularly limited, and examples thereof include an alkynyl group, a substituted silyl group, an aryl group, a heteroaryl group, and a cyano group. For the explanation of the aryl group, the preferred range, and specific examples, see the above description of the "aryl group." The alkynyl group may be linear, branched, or cyclic. The number of carbon atoms in the alkynyl group is preferably 2 to 20, more preferably 2 to 10, and even more preferably 2 to 6. For example, an ethynyl group, a propynyl group, a butynyl group, etc. can be exemplified. At least one hydrogen atom in the alkynyl group may be substituted with a substituent. Examples of the substituent include an alkyl group, a halogenated alkyl group, a dialkoxyalkyl group, a substituted silyl group, an aryl group, and a pinacolatoboryl group. For the explanation, preferred range, and specific examples of the substituted silyl group, the description of the substituted silyl group as a substituent of the condensed ring below can be referred to, and for the explanation, preferred range, and specific examples of the aryl, the description of the "aryl group" above can be referred to. The alkyl group as a substituent of the alkynyl group may be linear, branched, or cyclic, but is preferably linear or branched. The number of carbon atoms in the alkyl group is preferably 1 to 20. Specific examples of the linear alkyl group include methyl, ethyl, and n-propyl groups, as well as long-chain alkyl groups such as dodecyl, tridecyl, tetradecyl, pentadecyl, and hexadecyl groups. Specific examples of the branched alkyl group include branched alkyl groups having 3 to 6 carbon atoms, such as isopropyl, isobutyl, sec-butyl, tert-butyl, isopentyl, neopentyl, tert-pentyl, and isohexyl. The halogenated alkyl group as the substituent of the alkynyl group may be a halogenated alkyl group in which all hydrogen atoms of the alkyl group are replaced with halogen atoms, or a partially halogenated alkyl group in which some hydrogen atoms of the alkyl group are replaced with halogen atoms. The description of the alkyl group substituted with halogen atoms, the preferred range, and specific examples can be referred to the description of the "alkyl group" above. Examples of halogen atoms include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms, and fluorine atoms are preferred. The dialkoxyalkyl group as a substituent of the alkynyl group preferably has a structure in which two alkoxy groups are bonded to the terminal carbon atom of the alkyl group. For the explanation of the alkyl group constituting the "dialkoxyalkyl group", the preferred range and specific examples, the description of the "alkyl group" above can be referred to. The two alkoxy groups constituting the "dialkoxyalkyl group" may be linear or branched. The number of carbon atoms in the alkoxy group is preferably 1 to 20, It is more preferably 1 to 10, and even more preferably 1 to 6. Specific examples of the alkoxy group include a methoxy group, an ethoxy group, an n-propoxy group, and an isopropoxy group. The two alkoxy groups constituting the "dialkoxyalkyl group" may be the same or different. The substituted silyl group as a substituent of the condensed ring may be any of mono-substituted silyl group, di-substituted silyl group, and tri-substituted silyl group, but is preferably a tri-substituted silyl group. In the di-substituted silyl group and the tri-substituted silyl group, the multiple substituents may be the same or different from each other. Examples of the substituent of the substituted silyl group include an alkyl group and an aryl group. The alkyl group may be linear, branched, or cyclic, but is preferably linear or branched. The number of carbon atoms of the alkyl group may be 1 or more, or 2 or more, but is preferably 2 or more, and more preferably 3 or more. In addition, when the substituted silyl group is a trialkylsilyl group, the total number of carbon atoms of the three alkyl groups is preferably 6 or more. The upper limit of the number of carbon atoms is not particularly limited, but is preferably 20 or less. For the explanation of the aryl group, the preferred range, and specific examples, the above description of the "aryl group" can be referred to. Specific examples of the substituted silyl group include a trimethylsilyl group, a triethylsilyl group, a tri-n-propylsilyl group, a triisopropylsilyl group, and a triphenylsilyl group. The heteroaryl group as a substituent of the condensed ring is preferably composed of a monocyclic aromatic heterocycle. Examples of heteroatoms constituting the aromatic heterocycle include nitrogen, oxygen, and sulfur atoms. The aromatic heterocycle may contain one or more heteroatoms. When the aromatic heterocycle contains two or more heteroatoms, the heteroatoms may be the same or different. It is more preferable that the heteroaryl group is composed of an aromatic heterocycle having 5 or 6 ring members, 1 to 3 of which are heteroatoms. Specific examples of aromatic heterocycles constituting the heteroaryl group include a pyrrole ring, an imidazole ring, a pyridine ring, a pyridazine ring, a pyrimidine ring, a pyrazine ring, a triazine ring, a furan ring, a thiophene ring, an oxazole ring, and a thiazole ring. At least one hydrogen atom of the aromatic heterocycle may be substituted with a substituent.

[0030] The position of the substituent of the fused ring is not particularly limited, and the number of substitutions may be any number within the range not exceeding the number of substitutable positions. The number of substituents may be selected, for example, from the range of 1 to 4, from the range of 1 to 3, or may be 1 or 2. For example, when a fused ring containing a benzene ring has two substituents, the positions of the substituents may be ortho positions of the benzene ring, meta positions, or para positions. In addition, when a fused ring is substituted with two or more substituents, the substituents may be the same or different from each other.

[0031] Specific examples of the acceptor are shown below, but the acceptor that can be used in the present invention should not be interpreted as being limited by these specific examples. In addition, known acceptor compounds, including those described in WO2023 / 037848A1

[0042] , can also be used in the present invention.

[0032] [ka] JPEG2025036025000010.jpg131163

[0033] A specific example of an acceptor that emits UVB light is the following compound described in Angew. Chem. Int. Ed. 2023, 62, e202215340. In the following formula, TIPS represents a triisopropylsilyl group.

[0034] [ka]

[0035] Specific examples of acceptors that emit UVB light include the following compounds: [ka]

[0036] (The lowest excited singlet energy level S 1 and the lowest excited triplet energy level T 1 (Method of measurement) The lowest excited singlet energy level S of the compound used in the present invention 1 is obtained by measuring the fluorescence spectrum of the compound in solution and converting the wavelength of the fluorescence peak on the shortest wavelength side into an energy value using the following conversion formula. 1 can be obtained by putting the compound into solution, measuring the phosphorescence spectrum, and converting the wavelength of the phosphorescence peak into an energy value using the following conversion formula. The solvent used to put the compound into solution should be one that can dissolve the compound (e.g., tetrahydrofuran). The concentration of the solution should be one that allows spectrum measurement (e.g., 100 μM). The emission spectrum can be measured using a JASCO FP-8300 made by JASCO Corporation, using a xenon lamp as the excitation light source. Conversion formula: S 1 [eV]=1239.85 / λ F Conversion formula: T 1 [eV]=1239.85 / λ P In the above formula, λ F is the fluorescence peak wavelength [nm], λ P is the phosphorescence peak wavelength [nm].

[0037] [Framework aspect] The skeleton includes at least a donor and an acceptor. The skeleton may be composed of only a donor and an acceptor, or may include other components. An example of the other components is a matrix resin. Here, the term "matrix resin" refers to a resin contained in the skeleton and serving as a dispersion medium for at least one of the donor and the acceptor. In a preferred embodiment of the present invention, the framework is made of a material in which a donor is dispersed in an acceptor. In a preferred embodiment of the present invention, the framework is made of a material in which a donor and an acceptor are dispersed in a matrix resin. In one embodiment of the present invention, the donor is present on the surface of the skeleton. Here, the "surface" of the skeleton on which the donor is present means both the outer surface of the skeleton and the inner surface surrounding the through-hole of the skeleton. However, the donor only needs to be present on at least a part of the surface of the skeleton, and may be present on the entire surface of the skeleton or on a part of the surface of the skeleton, but it is preferable that the donor is present at least on the inner surface surrounding the through-hole. In addition, the donor present on the surface of the skeleton may be attached to the surface or may be absorbed from the surface to the inside (present near the surface). In one embodiment of the present invention, the skeleton contains an acceptor, and the donor is present on the surface of the skeleton. In this case, the part of the skeleton excluding the donor may be composed of only the acceptor, or may be composed of a material in which the acceptor is dispersed in the matrix resin.

[0038] [Matrix resin] As the matrix resin, a polymer that is in a solid state at room temperature (25° C.) can be used. In the present invention, the term "polymer" refers to a polymeric compound having structural units derived from a sufficient number of monomers to exhibit a solid state at room temperature (usually a polymeric compound having structural units derived from 30 or more monomers).

[0039] The polymer may be appropriately selected from known polymers, but is preferably an amorphous polymer because of its high light transmittance. The fact that it is an amorphous polymer can be confirmed by the fact that it does not show a clear melting point. Examples of polymers include acrylic, vinyl, styrene, allyl, divinyl, epoxy, isocyanate, diamine, dicarboxylic acid, dicarboxylic acid chloride, diol, dithiol, cyclic olefin, fluorine-containing, isothiocyanate, bismaleimide, lactone, lactide, and disulfonyl chloride homopolymers, or copolymers of two or more of these. For example, polystyrene, poly(alkyl methacrylate), poly(alkyl acrylate), poly(N-alkylacrylamide), and polyvinyl alcohol can be preferably used, and bioplastics may also be used. Bioplastics contain substances derived from renewable organic resources as raw materials, and can be appropriately selected from those synthesized chemically or biologically. For example, cellulose and protein can be used, and it is particularly preferable to use biodegradable biopolymers. In the present invention, two or more of these polymers may be mixed and used. In one embodiment of the present invention, the photon upconversion porous body includes a matrix resin containing polymethyl methacrylate. In one embodiment of the present invention, the photon upconversion porous body includes a matrix resin containing polyvinyl alcohol. The degree of polymerization of the polymer can be selected from the range of 10 to 50,000, and may be 10 to 1,000, 1,000 to 10,000, or 10,000 to 50,000. The weight-average molecular weight of the polymer can be selected from the range of 1,000 to 5,000,000, and may be 1,000 to 100,000, 100,000 to 1,000,000, or 1,000,000 to 5,000,000. Here, the weight-average molecular weight of the polymer is the weight-average molecular weight measured by gel permeation chromatography (GPC).

[0040] The polymer may have a glass transition temperature of room temperature (25° C.) or higher, or may have a glass transition temperature lower than room temperature. When a polymer having a glass transition temperature of room temperature or higher is used, the polymer exhibits a hard property, so molecular diffusion is unlikely to occur, and energy transfer between compound molecules is mainly performed by energy diffusion. When a polymer having a glass transition temperature lower than room temperature is used, the polymer exhibits a soft property, so energy transfer by molecular diffusion may also occur. The glass transition temperature of a polymer can be measured by a differential scanning calorimeter.

[0041] In addition, when the photon upconversion porous body is manufactured by the first manufacturing method or the second manufacturing method described later, it is preferable to select a polymer of the matrix resin that is highly resistant to the solvent used to dissolve and remove the porous template. In addition, in the photon upconversion porous body used in a flow system or a batch system using an organic solvent, it is preferable to select a polymer of the matrix resin that is highly resistant to the organic solvent. In this case, in order to increase the resistance to the organic solvent, a crosslinked structure may be introduced between the polymer chains of the matrix resin, or a coating layer such as a silica coat (a coating layer containing silicon dioxide) may be formed on the surface of the skeleton. In one embodiment of the present invention, the matrix resin includes an epoxy-based polymer having a crosslinked structure. In one embodiment of the present invention, the skeleton includes a matrix resin containing polyvinyl alcohol, and has a coating layer on the surface of the skeleton, and the coating layer is, for example, a silica coat.

[0042] [Coating layer] As described above, the coating layer formed on the skeleton can be a silica coat. The coating layer formed on the skeleton may be formed by treating the surface of the skeleton with a silane coupling agent. An example of the silane coupling agent is a compound represented by the following general formula (3). General formula (3) R 1 n Six (4-n) In the general formula (3), X represents a hydrolyzable group that generates a silanol group upon hydrolysis, and R 1 represents a hydrolyzable group which produces a silanol group upon hydrolysis, or a substituted or unsubstituted alkyl group; and n is an integer of 1 to 3. In the silane coupling agent represented by the general formula (3), a silanol group or a silyl group produced by hydrolysis of X reacts with a functional group on the surface of the core particle to form a coating layer. In the general formula, X and R 1 Examples of the "hydrolyzable group that forms a silanol group" include alkoxy groups such as methoxy and ethoxy groups, and halogen groups. R 1 Examples of the substituent of the substituted alkyl group include a halogen group, an amino group, an epoxy group, and a phenyl group. Examples of the silane coupling agent represented by general formula (3) include tetraethoxysilane, triethoxyalkylsilane, diethoxydialkylsilane, ethoxytrialkylsilane, tetramethoxysilane, trimethoxyalkylsilane, dimethoxydialkylsilane, methoxytrialkylsilane, and trichloroalkylsilane. The silane coupling treatment for forming a coating layer on the skeleton can be carried out according to a conventional method.

[0043] The thickness of the coating layer formed on the skeleton can be selected, for example, from the range of 1.0 to 500.0 nm, may be selected from the range of 1.0 to 10.0 nm, may be selected from the range of 10.0 to 100.0 nm, or may be selected from the range of 100.0 to 500.0 nm.

[0044] [Donor and acceptor ratio and content] In the embodiment of the skeleton in which the donor is dispersed in the acceptor, and in the embodiment of the skeleton in which the donor and the acceptor are dispersed in the matrix resin, the molar ratio of the donor to the acceptor [(moles of donor / moles of acceptor)×100] is preferably 0.01 to 20%, more preferably 0.1 to 10%, and even more preferably 1 to 5%. When the absorbance of the donor at the emission wavelength of the acceptor is small, the concentration of the donor can be increased to allow more absorption of the excitation light.

[0045] In the embodiment of the skeleton in which the donor and the acceptor are dispersed in the matrix resin, the total amount of the donor and the acceptor is the ratio to the total amount of the donor, the acceptor, and the matrix resin (R DA ) is preferably 10% by weight or more, may be 20% by weight or more, may be 30% by weight or more, or may be 40% by weight or more. DA It may be 90% by weight or less, 80% by weight or less, or 70% by weight or less. R DA =[(W D +W A ) / (W D +W A +W P )] x 100 W D : Donor content W A : Acceptor content W P : Polymer content

[0046] In an embodiment in which the donor is present on the surface of the scaffold, the amount of the donor is the ratio R D The ratio R is preferably 0.001% by weight or more, may be 0.01% by weight or more, 0.1% by weight or more, or may be 1% by weight or more. D It may be 40% by weight or less, 5% by weight or less, or 1% by weight or less. In a case where the donor is present on the surface of the skeleton and the acceptor is dispersed in the matrix resin, the content of the acceptor is determined by the ratio to the total amount of the acceptor and the matrix resin (R calculated by the following formula). A ) is preferably 10% by weight or more, may be 20% by weight or more, may be 30% by weight or more, or may be 40% by weight or more. A It may be 90% by weight or less, 80% by weight or less, or 70% by weight or less. R A =[(W A ) / (W A +W P )] x 100 W A : Acceptor content W P : Polymer content

[0047] [Other ingredients] The skeleton may further contain other components in addition to the donor, acceptor, and matrix resin, such as a colorant and an antioxidant.

[0048] [Through hole] The photon upconversion porous body of the present invention is characterized in that it has through-holes. The "through hole" in the present invention means a continuous hole that penetrates from one outer surface to the other outer surface of the photon upconversion porous body. In other words, the "through hole" in the present invention is a continuous hole that opens on at least one outer surface and the other outer surface of the porous body. Here, the through hole may be open on two outer surfaces, or may be open on three or more outer surfaces. The photon upconversion porous body of the present invention has such through-holes, and when the porous body is placed in a flow path and a fluid is passed through it, the fluid easily passes from one side to the other side through the through-holes, and exhibits high permeability. Therefore, the photon upconversion porous body of the present invention can also be used in flow systems, and has a wide range of applications and is highly useful. The through holes may be those that penetrate linearly from one outer surface to the other outer surface, or those that penetrate irregularly from one outer surface to the other outer surface, or may have a three-dimensionally connected structure, or may have a three-dimensional co-continuous structure formed by the continuous pores and the skeleton.

[0049] The through-hole diameter of the photon upconversion porous body is, for example, 0.1 to 100 μm, preferably 1 to 10 μm. The through-hole diameter here means the average pore diameter, which is the value obtained by measuring the diameter of a true sphere that can pass through each hole present in a specific surface of the photon upconversion porous body, and dividing the sum by the number of holes measured. The surface to be measured can be the surface passing through the center of gravity of the photon upconversion porous body, but it is also possible to simply select a specific exposed surface and measure it. The photon upconversion porous body may have pores with one or both ends closed in addition to through holes, but in one embodiment of the present invention, there are no pores with a maximum diameter of 1 μm or more and closed at both ends. In a preferred embodiment of the present invention, there are no pores with a maximum diameter of 0.1 μm or more and closed at both ends. In a preferred embodiment of the present invention, all of the pores in the photon upconversion porous body are spatially connected and no closed pores exist.

[0050] [Shape and porosity of photon upconversion porous bodies] In the photon upconversion porous body of the present invention, the shape and size of the porous body are not particularly limited and can be appropriately selected depending on the application. Examples of the outer shape of the porous body include a film, a filter, a block, a cylinder, and a granule. The size of the porous body may be in the range of 1 mm to 10 m, for example, 5 mm to 10 cm, or for example, 20 cm to 10 m, in terms of maximum diameter. In one embodiment of the present invention, the photon upconversion porous body is in the form of a film, and has through-holes that open on the front and back surfaces of the film. In one embodiment of the present invention, the photon upconversion porous body is in the form of a filter, and has through-holes that open on the front and back surfaces of the filter. In one embodiment of the present invention, the photon upconversion porous body is a cube-shaped block, and has through-holes that open on at least two faces. In one embodiment of the present invention, the photon upconversion porous body is in the form of a cylinder, and has through-holes that open on the top and bottom faces. In one embodiment of the present invention, the photon upconversion porous body is in the form of a granule, and has through-holes that open on at least two points on the granule surface. Each through-hole in these embodiments may be open on only two faces, or may be open on three or more faces. One embodiment of the photon upconversion porous body of the present invention is a monolithic porous body. Here, the term "monolithic" refers to a porous body having three-dimensionally interconnected pores, and is formed by a three-dimensional co-continuous structure of interconnected pores and material skeleton.

[0051] The porosity of the photon upconversion porous body of the present invention is, for example, 1 to 20%, for example, 10 to 50%, for example, 30 to 80%. The porosity of the porous body can be calculated from the specific gravity of the skeleton by measuring the volume and mass of the entire porous body including the pores.

[0052] (Materials that photon upconversion porous media should not contain) The photon upconversion porous body of the present invention preferably does not contain heavy metals. Here, the "heavy metals" in "does not contain heavy metals" refer to metals having a specific gravity of 4 g / cm 3 The term "free of heavy metals" means that the composition is substantially free of heavy metals in any form, including heavy metals as constituent elements of compounds and heavy metals as simple substances, and does not exclude the inclusion of heavy metals as unavoidable impurities. Here, "substantially free of heavy metals" means that the content of heavy metals in the composition is 0.1 ppm or less.

[0053] <Light irradiation method> Next, the light irradiation method of the present invention will be described. The light irradiation method of the present invention is a light irradiation method in which a photon upconversion porous body having a framework including a donor and an acceptor and through-holes is irradiated with light, and the photon upconversion light (UC light) generated thereby is irradiated to a substance present in the through-holes. In the following description, the "substance" in the present invention is referred to as the "irradiated substance". For the description of the photon upconversion porous body used in the present invention, the description in the above <Photon upconversion porous body> can be referred to. The photon upconversion porous body used in the present invention has a high degree of freedom in designing its shape and dimensions. For example, it can take various shapes such as film, filter, block, and granular, and can be manufactured from fine ones such as granular ones to ones with large areas and large surface areas. Therefore, the shape and dimensions of the photon upconversion porous body can be easily adjusted according to the shape and size of the flow channel of the flow system and the batch type container described later.

[0054] In the present invention, the irradiated substance present in the through-hole is, for example, a substance that undergoes some kind of reaction due to UC light irradiated from the photon upconversion porous body. The reaction that occurs in the irradiated substance may be any reaction that occurs due to UC light, for example, a photochemical reaction. Examples of photochemical reactions include photoisomerization reactions, photocyclization reactions, photodimerization reactions, photofries transition reactions, etc., and examples of the irradiated substance include raw materials for organic synthesis using photochemical reactions, precursors for chemical modification using photochemical reactions, and objects to be sterilized by ultraviolet irradiation (for example, photodimerization reaction of thymine in DNA).

[0055] The irradiated substance present in the through-holes may be supplied from the outside of the photon upconversion porous body, or may be applied to the inner surface surrounding the through-holes during the manufacturing process of the photon upconversion porous body, but it is preferable that the irradiated substance is supplied from the outside. When the irradiated substance is supplied from the outside into the through-holes, the light irradiation method of the present invention may be performed in a flow system or a batch system. In a preferred embodiment of the present invention, the light irradiation method of the present invention is performed using a flow system. In the flow system, a photon upconversion porous body is placed in the flow path of a fluid containing an irradiated substance, and while the fluid is passing through the porous body, the photon upconversion porous body is irradiated with light whose wavelength overlaps with the absorption wavelength range of the donor. This light irradiation activates the UC emission mechanism, and the UC light is irradiated to the irradiated substance passing through the through hole. As a result, for example, a desired reaction occurs in the irradiated substance to generate a reactant, and the target reactant is obtained by separating and collecting this reactant downstream of the flow path. In the flow system, the irradiated substance is continuously supplied into the minute space inside the through hole, and the UC light is irradiated from the inner surface surrounding the through hole, so that the irradiated substance can be irradiated with the UC light uniformly and efficiently, and the irradiation time of the UC light on the irradiated substance can be precisely controlled. In the batch method, the photon upconversion porous body is immersed in a fluid containing the irradiated material, the fluid is stirred as necessary, and the porous body is irradiated with light whose wavelength overlaps with the absorption wavelength range of the donor. This light irradiation activates the UC emission mechanism, and the UC light is irradiated to the irradiated material that has permeated the through-holes. As a result, for example, the irradiated material undergoes a desired reaction to produce a reactant, which can be separated from other components of the porous body and fluid to obtain the desired reactant.

[0056] The fluid containing the irradiated substance may be a melt (melt) of the irradiated substance at or above its melting point, or a solution or dispersion containing the irradiated substance. The solvent for the solution and dispersion may be an organic solvent, water, or a mixed solvent of an organic solvent and water, but it is preferable to select a solvent to which the porous body has high resistance. If water is selected as the solvent, the present invention can be applied to a wide range of reactions in water, and is particularly useful because the present invention can be applied to a wide range of reactions including those related to living organisms and agriculture. If an organic solvent is selected as the solvent, the present invention can be applied to reactions of poorly water-soluble or water-insoluble substances, and can be applied to various reactions including those related to industry. The organic solvent can be appropriately selected from known organic solvents, and can be selected from, for example, aromatics such as benzene, toluene, xylene, and chlorobenzene; ethers such as diethyl ether, dibutyl ether, tetrahydrofuran, 1,4-dioxane, dimethoxyethane, and diethylene glycol dimethyl ether; esters such as methyl acetate, ethyl acetate, butyl acetate, and ethyl propionate; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; hydrocarbons such as hexane, heptane, octane, and nonane; halogenated hydrocarbons such as dichloromethane, chloroform, and 1,2-dichloroethane; organic acids such as formic acid, acetic acid, and propionic acid; polar solvents such as N,N-dimethylformamide, N,N-dimethylacetamide, and N-methylpyrrolidone; and mixed solvents thereof.

[0057] The content of the irradiated substance in the fluid is, for example, 0.01M to 0.1M, for example, 0.1M to 1M, for example, 1M to 10M.

[0058] In a preferred embodiment of the present invention, the light irradiated to the photon upconversion porous body is visible light. The visible light may be a single light having a maximum emission wavelength at a specific wavelength in the visible region, a composite light obtained by combining a plurality of visible light beams having different maximum emission wavelengths, or a composite light obtained by combining light beams of continuous wavelengths in the visible region. Examples of the irradiation source include sunlight, LED, Xe lamp, and laser. The irradiation intensity is 0.1 to 1000 mW / cm. 2 is preferably 0.5 to 100 mW / cm2 More preferably, the intensity is 1 to 50 mW / cm 2 The irradiation time is a time that allows the desired photoreaction to occur, and may be, for example, 1 minute or more.

[0059] <Light irradiation flow path> The light irradiation flow path of the present invention has a photon upconversion porous body disposed in a flow path through which a fluid containing a substance flows, and the photon upconversion porous body is a porous body having a framework containing a donor and an acceptor, and through holes. For an explanation of the photon upconversion porous body, please refer to the description in the <Photon upconversion porous body> section above, and for an explanation of the fluid containing the substance, please refer to the corresponding description in the <Light irradiation method> section above. The shape and size of the flow channel used in the present invention are not particularly limited, and examples thereof include column-type flow channels, tubular flow channels, chip-type flow channels, etc. The diameter of the flow channel may be, for example, in the range of 1 mm to 10 m, for example, in the range of 5 mm to 10 cm, or for example, in the range of 20 cm to 10 m.

[0060] <First manufacturing method for photon upconversion porous material> Next, a first production method for the photon upconversion porous body of the present invention will be described. The first manufacturing method of the photon upconversion porous body of the present invention is a manufacturing method of a photon upconversion porous body containing a donor and an acceptor and having through holes, and includes the steps of filling a fluid containing the donor and acceptor into a porous mold having through holes, solidifying the fluid, and then dissolving and removing the porous mold. For an explanation of the photon upconversion porous material produced in the present invention and the donor and acceptor used in the present invention, please refer to the description in the above <Photon upconversion porous material> section.

[0061] The porous template having through holes used in the present invention is a template whose internal space has a shape corresponding to the skeleton of the desired photon upconversion porous body. In one embodiment of the present invention, the porous template is a monolith, for example, a porous silica monolith. Since the porous silica monolith is easily dissolved in a solvent in the process of dissolving and removing the porous template, it is preferable that the porous silica monolith is a porous silica monolith obtained by low-temperature firing of a gel prepared by a sol-gel method. The temperature of the low-temperature firing is, for example, 100 to 300°C, for example, 300 to 600°C, for example, 600 to 900°C.

[0062] The fluid containing the donor and the acceptor used in the present invention may be a melt at or above the melting point of the mixture of the donor and the acceptor, or may be a solution or dispersion containing the donor and the acceptor. The fluid may also contain a monomer material that is a structural unit of the matrix resin in addition to the donor and the acceptor. The monomer material may contain one type of monomer or two or more types of monomers. For an explanation of the matrix resin, please refer to the description in the above column [Polymer as matrix resin]. The solvent of the solution and the dispersion may be appropriately selected from known solvents. For specific examples, please refer to the description of "Solvent of the solution and the dispersion" in the above column <Light irradiation method>.

[0063] In order to manufacture a photon upconversion porous body by the manufacturing method of the present invention, first, a fluid containing a donor and an acceptor is filled into the porous mold and the fluid is solidified. The solidification of the fluid may be by solidification by cooling or by solid precipitation by polymerization reaction of a monomer material. The porous template is then dissolved and removed, leaving a photon upconversion porous medium that corresponds to the internal shape of the porous template. To dissolve the porous template, a solvent that dissolves the porous template but does not dissolve the photon upconversion porous body can be used. Examples of the solvent include an alkaline solution such as an aqueous solution of an alkali metal hydroxide or an aqueous solution of an alkaline earth metal hydroxide, preferably an aqueous solution of an alkali metal hydroxide such as sodium hydroxide or potassium hydroxide, more preferably an aqueous solution of sodium hydroxide.

[0064] <Second manufacturing method for photon upconversion porous bodies> The second manufacturing method of the photon upconversion porous body of the present invention is a manufacturing method of a photon upconversion porous body containing a donor and an acceptor and having through holes, and includes the steps of filling a fluid containing an acceptor into a porous mold having through holes, solidifying the fluid, dissolving and removing the porous mold, and attaching the donor to the surface of the obtained porous body. For an explanation of the photon upconversion porous material produced in the present invention and the donor and acceptor used in the present invention, please refer to the description in the above <Photon upconversion porous material> section.

[0065] The fluid containing the acceptor used in the present invention may be a melt of the acceptor at or above its melting point, or a solution or dispersion containing the acceptor. The fluid containing the acceptor may be composed of only the acceptor, or may contain a monomer material that is a structural unit of the matrix resin. The monomer material may contain one type of monomer, or may contain two or more types of monomers. For an explanation of the matrix resin, please refer to the description in the above column of [Polymer as matrix resin]. The solvent of the solution and dispersion may be appropriately selected from known solvents. For specific examples, please refer to the description of "Solvent of solution and dispersion" in the above column of <Light irradiation method>.

[0066] To manufacture a photon upconversion porous body by the manufacturing method of the present invention, first, a fluid containing an acceptor is filled into the porous mold and the fluid is solidified. The fluid may be solidified by cooling, or may be solidified by polymerization reaction of a monomer material. Next, the porous mold is dissolved and removed. This results in an acceptor-containing porous body that corresponds to the internal shape of the porous mold. For an explanation of the porous mold and the solvent for the porous mold, please refer to the description in the "First manufacturing method" column above. Next, a donor is attached to the surface of the obtained acceptor-containing porous body to obtain a photon-upconversion porous body. Here, the "surface" of the porous body means both the outer surface of the porous body and the inner surface of the through-hole inside the porous body (the inner surface surrounding the through-hole of the skeleton). However, the donor only needs to be attached to at least a part of the surface of the porous body, and may be attached to the entire surface of the porous body or to a part of the surface, but it is preferable to attach it to at least the inner surface of the through-hole. The attachment of the donor to the surface of the porous body can be performed, for example, by immersing the acceptor-containing porous body in a micellar solution of the donor, and then removing the porous body from the micellar solution, washing and drying it. The donor attached to the surface of the acceptor-containing porous body may remain on the surface as it is in the completed photon-upconversion porous body, or may be absorbed inside the skeleton.

[0067] <Third manufacturing method for photon upconversion porous bodies> The third manufacturing method for a photon upconversion porous body of the present invention is a manufacturing method for a photon upconversion porous body having a skeleton including a donor and an acceptor and through holes, and includes the steps of preparing a solution in which a donor, an acceptor, a monomer and a polymerization initiator are dissolved in two or more solvents, polymerizing the monomer to cause phase separation into a solid phase having the skeleton and a liquid phase, and then removing the liquid phase. For an explanation of the photon upconversion porous material produced in the present invention and the donor and acceptor used in the present invention, please refer to the description in the above <Photon upconversion porous material> section.

[0068] When preparing a solution according to the third manufacturing method, two or more types of solvents are used. At this time, it is preferable to select one or more types of good solvent and one or more types of poor solvent. As the good solvent, an aromatic non-polar solvent such as toluene can be preferably selected. As the poor solvent, a polar solvent such as propanol can be preferably selected. It is preferable to use a smaller amount of the good solvent than the poor solvent, and the upper limit can be set to, for example, 30% by volume or less, 25% by volume or less, or 20% by volume or less of the total solvent amount, and the lower limit can be set to, for example, 5% by volume or more, 10% by volume or more, or 15% by volume or more. If the amount of the good solvent is increased, the pores of the obtained photon upconversion porous body tend to become finer. On the other hand, if the amount of the good solvent is excessively increased, the solubility of the donor and acceptor tends to decrease. The prepared solution can be ultrasonically treated or nitrogen bubbled before polymerizing the monomer. By polymerizing the monomer according to the third production method, the solid phase of the polymer and the liquid phase of the solvent are separated. At this time, the polymer becomes a solid phase having a porous skeleton, and phase separation occurs in a state in which the liquid phase fills the porous pores. The polymerization is carried out under conditions that make it easy to form such a porous skeleton. For example, the polymerization can be carried out at 50 to 100°C for 1 to 24 hours. After the polymerization, the liquid phase is removed. At this time, the solvent used in the polymerization reaction may be exchanged with another solvent. For example, the solvent exchange can be carried out by immersing in ethanol. The solvent can be removed by appropriately selecting a means from among ordinary solvent removal methods such as drying under reduced pressure. According to the third manufacturing method, since it is not necessary to use a porous silica monolith, a photon upconversion porous body can be easily manufactured. The third manufacturing method is useful in that it is highly reproducible and the porous structure can be controlled. EXAMPLES

[0069] The features of the present invention will be explained in more detail below with reference to examples and comparative examples. The materials, amounts used, ratios, processing contents, processing procedures, etc. shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be interpreted as being limited by the specific examples shown below. In the following examples, a spectrophotometer (JASCO: V-780) was used to measure the absorption spectrum, and a spectrofluorophotometer (JASCO: FP-8300) was used to measure the emission spectrum. UC efficiency η UC was calculated by a relative method using the following compound D1 as a standard substance. In this relative method, the phosphorescence quantum yield of the compound D1 solution, the absorbance and emission spectrum of each solution to be measured, the excitation light intensity during measurement, and the refractive index of the solvent are used, and a multichannel spectrometer (Otsuka Electronics Co., Ltd.: MCPD-9800) was used to measure the emission spectrum. A fluorescence lifetime measurement device (Hamamatsu Photonics Co., Ltd.: Quantaurus-Tau C11367-02 / C11567-01) was used to measure the UC emission lifetime.

[0070] [Donors, acceptors (photon upconversion compositions), and polymers used in the examples] The donors, acceptors and polymers used in this example are shown below. [ka] (Production of Porous Silica Monoliths) In this example, a porous silica monolith prepared by the following sol-gel method was used as the porous template. Urea (450 mg) and polyethylene glycol (PEG10000: Sigma-Aldrich) (575 mg) were added to 10 mM acetic acid aqueous solution (5 mL) and stirred to obtain a solution. Tetramethoxysilane (2.5 mL) was added to this solution in an ice bath and stirred for 90 minutes. This reaction solution was poured into a straight polypropylene pipe (inner diameter: 4 mm or 6 mm) (it can be freely molded by transferring it to any container) and left to stand overnight in a water bath at 30 °C to gel. The obtained gel was heated at 110 °C for 4 hours, cooled to room temperature, removed from the straight pipe, and immersed in water five times and in a water / ethanol = 2 / 1 solution three times, each for half a day, to perform solvent exchange. The washed gel was dried in air and then calcined at 600 °C for 5 hours to obtain a white porous silica monolith. A scanning electron microscope (SEM) photograph of the porous silica monolith is shown in Figure 2.

[0071] (Example 1) Preparation and evaluation of UC porous body 1 containing UC composition consisting of compound D1 and compound A1 and polystyrene (using porous silica monolith) FIG. 3 shows an outline of the shape of the porous silica monolith used in this example, and the composite and UC porous body 1 formed in this production process. First, a solution of azobisisobutyronitrile initiator (2 mg), compound A1 (23 mg, 47 μmol), and compound D1 (0.47 μmol) dissolved in styrene (200 mg) was bubbled with nitrogen for 2 minutes, then porous silica monolith (5 mg) was added and sealed, and the solution was allowed to penetrate and fill the porous silica monolith by leaving it for 30 minutes. The silica monolith filled with the solution was heated in a water bath at 90 ° C for 6 hours to polymerize, cooled to room temperature, washed with ethanol, and dried overnight. The composite of this polymer and silica monolith was immersed in a 1 M NaOH aqueous solution (1 mL) for 1 week to dissolve and remove the silica monolith. The remaining polymer was immersed in water for 1 day three times to exchange the solvent, and then dried under reduced pressure to obtain UC porous body 1. An SEM photo of UC porous body 1 is shown in Figure 4. The SEM photo confirmed that UC porous body 1 has a bicontinuous structure on the micrometer scale.

[0072] [Evaluation of UC characteristics] The UC porous body 1 produced in Example 1 was irradiated with a blue laser (λ EX : 445 nm) excitation intensity 1.7 to 773 Wcm -2 The UC emission spectrum was measured by changing the UC efficiency in the range of . The measured UC emission spectrum is shown in Figure 5. The measurement was performed by placing a 425 nm short-wavelength pass filter between the sample and the spectrometer. UC efficiency η UC was 0.15%.

[0073] (Example 2) Preparation and evaluation of UC porous body 2 in which compound D2 is attached to the surface of a porous body of compound A2 FIG. 6 shows an outline of the porous body (monolith) of compound A2 formed in this example and UC porous body 2 in which compound D2 is attached to the surface of this porous body. Porous silica monolith (10 mg) and compound A2 (100 mg) were sealed in a glass tube under reduced pressure, and the molten liquid of compound A2 was filled into the porous silica monolith by heating for 60 minutes at 230 ° C, which is above the melting point of compound A2. The porous silica monolith filled with the molten liquid was cooled to room temperature to solidify compound A2, and then excess compound A2 was removed. The monolith was then immersed in a 1M NaOH aqueous solution (1 mL) for one week to dissolve and remove the silica monolith. The remaining molded body was immersed in water for half a day three times to exchange the solvent, and then dried under reduced pressure to obtain a porous body (monolith) of compound A2. An SEM photograph of the porous body of compound A2 is shown in Figure 7. Next, this porous body (3.5 mg) was immersed in a micellar aqueous solution of compound D2 (25 μM, water: 350 μL) for 2 hours. After immersion, the porous body was taken out of the micellar aqueous solution, washed three times with water, and then vacuum dried to obtain UC porous body 2 in which compound D2 was attached to the surface of the porous body of compound A2. An SEM photograph of UC porous body 2 is shown in FIG. SEM images confirmed that UC porous body 2 had a bicontinuous structure on the micrometer scale. Furthermore, powder X-ray diffraction, thermogravimetric analysis, and luminescence property measurements confirmed that the obtained UC porous body 2 was made of compound A2 with compound D2 uniformly adsorbed on the porous body surface, and it was also confirmed that energy transfer occurred from compound D2 to compound A2.

[0074] [Evaluation of UC characteristics] The UC emission spectrum of the UC porous body 2 prepared in Example 2 measured under the same conditions as in Example 1 is shown in FIG. th is 705.9mW / cm 2 , UC luminescence lifetime τ T was 345 μs.

[0075] (Example 3) Preparation and evaluation of UC porous body 3 containing UC composition consisting of compound D1 and compound A1 and polystyrene (no porous silica monolith used) FIG. 10 shows an outline of the changes caused by the polymerization and solvent removal carried out in this example, and the porous body 3 produced. A solution of azobisisobutyronitrile initiator (2 mg), compound A1 (35 mg, 71.6 μmol), compound D1 (1.43 μmol), styrene (100 μL), divinylbenzene (100 μL), toluene (50 μL), and 2-propanol (250 μL) was ultrasonically treated for 15 minutes, and then nitrogen bubbling was performed for 2 minutes. After heating at 90 ° C for 5 hours in a water bath or oven and cooling to room temperature, the solution was immersed in ethanol for 12 hours for solvent exchange. After that, the solution was dried under reduced pressure at 80 ° C for 6 hours to obtain UC porous body 3. An SEM photograph of the obtained porous body 3 is shown in FIG. 11.

[0076] [Evaluation of UC characteristics] The UC emission spectrum of the UC porous body 3 prepared in Example 3 measured under the same conditions as in Example 1 is shown in FIG. th is 0.98mW / cm 2 , UC luminescence lifetime τ T is 5.42ms, UC efficiency η UC was 0.43%. [Industrial Applicability]

[0077] The photon upconversion porous body of the present invention can also be applied to a flow system. Therefore, according to the present invention, UC light irradiation in a flow system becomes possible in various fields that utilize photochemical reactions, which can greatly contribute to improving reaction accuracy and reaction efficiency. Therefore, the present invention has a high industrial applicability.

Claims

1. A photon upconversion porous body having a framework containing a donor and an acceptor and through-holes.

2. The photon upconversion porous body according to claim 1, wherein the through-pore diameter of the porous body is 0.1 to 100 μm.

3. The photon upconversion porous body of claim 1 , wherein the donor is dispersed in the acceptor.

4. The photon upconversion porous body according to claim 1 , wherein the donor is present on the surface of the framework.

5. The photon upconversion porous body according to claim 1 , further comprising a matrix resin in the skeleton portion.

6. The photon upconversion porous body according to claim 5 , wherein the acceptor is dispersed in the matrix resin.

7. The photon upconversion porous body according to claim 6 , wherein the donor is further dispersed in the matrix resin.

8. The photon upconversion porous body according to claim 1 , wherein the framework is monolithic.

9. 2. The photon upconversion porous body according to claim 1, which absorbs visible light and emits ultraviolet light.

10. The photon upconversion porous body according to claim 9, which emits ultraviolet light having a wavelength of 280 to 320 nm.

11. A light irradiation method comprising irradiating the photon upconversion porous body according to any one of claims 1 to 10 with light, and irradiating the resulting photon upconversion light onto a substance present in the through-holes.

12. The light irradiation method according to claim 11 , wherein the substance is supplied into the through-holes from outside the photon up-conversion porous body.

13. The light irradiation method according to claim 11, wherein the photon up-conversion porous body is irradiated with light while a fluid containing the substance is transmitted through the photon up-conversion porous body.

14. A flow path for light irradiation, comprising the photon upconversion porous body according to any one of claims 1 to 10 disposed in a flow path for a substance-containing fluid to flow.

15. A method for producing a photon upconversion porous body having a skeleton including a donor and an acceptor and through-holes, comprising the steps of: The manufacturing method includes a step of filling a fluid containing the donor and the acceptor into a porous mold having through holes, solidifying the fluid, and then dissolving and removing the porous mold to form the skeleton.

16. The method of claim 15 , wherein the fluid further comprises a monomer, and the solidification is performed by polymerizing the monomer.

17. A method for producing a photon upconversion porous body having a skeleton including a donor and an acceptor and through-holes, comprising the steps of: The manufacturing method includes the steps of filling a fluid containing the acceptor into a porous mold having through holes, solidifying the fluid, and then dissolving and removing the porous mold, and attaching the donor to the surface of the resulting porous body to form the framework.

18. A method for producing a photon upconversion porous body having a skeleton including a donor and an acceptor and through-holes, comprising the steps of: The production method is characterized by preparing a solution in which the donor, the acceptor, a monomer and a polymerization initiator are dissolved in two or more solvents, polymerizing the monomer to cause phase separation into a solid phase having the skeleton and a liquid phase, and removing the liquid phase.

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