Optical sensor material, optical sensor and display device using same, and compound

Abstract

The purpose of the present invention is to provide an optical sensor material that has sensitivity in a green light region and a red light region, and is suitable for a vacuum deposition process. The present invention is an optical sensor material having a structure that is represented by general formula (1). In general formula (1), R1-R8 are each independently selected from the group consisting of a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, a heteroaryl group, an alkoxy group, a halogen atom, a cyano group, a nitro group, a silyl group, and a boryl group. R9-R12 are each independently an alkyl group that has fewer than 6 carbon atoms. X is an oxygen atom, a sulfur atom, or a selenium atom. Y1-Y4 are each independently selected from the group consisting of NR13, an oxygen atom, and a sulfur atom. R13 is a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or a heteroaryl group. Z1 and Z2 are each independently selected from the group consisting of a carbon atom, a silicon atom, and a germanium atom.

Description

Optical sensor materials, optical sensors and display devices using the same, and compounds

[0001] The present invention relates to an optical sensor material, an optical sensor and display device using the same, and a compound.

[0002] In recent years, IoT (Internet of Things) and big data have attracted attention, and the importance of sensing technologies that acquire the various types of data supporting them has increased. There are various methods of sensing technology, but among them, optical sensing is a highly useful sensing technology because it can be used in a wide range of applications, such as by changing the sensing target by selecting the target wavelength.

[0003] A light sensor generally comprises a photoelectric conversion element that converts light into electrical energy and a light-emitting element independently. It senses an object by irradiating it with light from the light-emitting element and receiving the light that has been transmitted or reflected from the object with the photoelectric conversion element (see, for example, Non-Patent Document 1). Such a light sensor can acquire biological information such as fingerprints, vein shapes, and blood oxygen concentration by using, for example, green light, red light, or near-infrared light. Furthermore, by forming the substrate, light-emitting element, and light-receiving element mainly from organic materials, it is possible to construct a thin and flexible device (see, for example, Non-Patent Document 2).

[0004] In general, pyromethene compounds are being considered as photoelectric conversion materials used in photoelectric conversion elements in organic solar cells and organic photodetectors (see, for example, Patent Document 1). Pyromethene compounds generally have a high extinction coefficient, and by selecting substituents, the absorption wavelength range can be designed to a desired range.

[0005] Furthermore, as a photoelectric conversion material aimed at increasing the efficiency of organic solar cells, a Push-Pull type material is being investigated in which an electron-donating skeleton of cyclopentadithiophene and an electron-withdrawing skeleton of benzothiadiazole are alternately linked (see, for example, Non-Patent Documents 3-4).

[0006] Journal of the Society for Information Display, 2019, Vol. 27, pp. 361-371; Science Advances, 2016, Vol. 2, e1501856; Advanced Materials, 2006, Vol. 18, pp. 2884-2889; Organic Electronics, 2012, Vol. 13, pp. 2967-2974

[0007] Patent No. 6558243

[0008] However, pyromethene compounds described in Patent Document 1 generally have a narrow half-width, making them suitable for wavelength-selective applications such as absorbing only green light or only red light for photoelectric conversion. However, they are not suitable for applications where both green and red light are absorbed and photoelectric conversion is performed, but a color filter is used to separate the green and red light, thereby creating separate optical sensors that are sensitive only to green light and optical sensors that are sensitive only to red light.

[0009] Furthermore, while the Push-Pull type materials described in Non-Patent Documents 3-4 have a wide half-width and can absorb both green and red light for photoelectric conversion, most of them are formed by coating processes, making it difficult to apply them to devices fabricated by vacuum deposition processes, such as the photosensor described in Non-Patent Document 1.

[0010] Therefore, the present invention aims to provide an optical sensor material that is sensitive to the green light region and the red light region and is suitable for vacuum deposition processes.

[0011] The present invention has the following configuration: [1] A light sensor material having a structure represented by the following general formula (1).

[0012]

[0013] In the above general formula (1), R １ ~R ８is independently selected from the group consisting of a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, a heteroaryl group, an alkoxy group, a halogen atom, a cyano group, a nitro group, a silyl group, and a boryl group. R ９ ~R １２ is independently an alkyl group having less than 6 carbon atoms. X is an oxygen atom, a sulfur atom, or a selenium atom. Y １ ~Y ４ is independently selected from the group consisting of NR １３ , an oxygen atom, and a sulfur atom. R １３ is a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or a heteroaryl group. Z 1 and Z ２ are independently selected from the group consisting of a carbon atom, a silicon atom, or a germanium atom. [2] R ９ ~R １２ are each independently a methyl group or an ethyl group, the photosensor material according to [1]. [3] R ９ ~R １２ is a methyl group, the photosensor material according to [1] or [2]. [4] X is a sulfur atom, the photosensor material according to any one of [1] to [3]. [5] Y １ ~Y ４ is a sulfur atom, the photosensor material according to any one of [1] to [4]. [6] Z １ and Z ２[1] to [5], wherein each of the elements is independently a carbon atom or a silicon atom. [7] A photosensor that converts light into electric current, wherein a photoelectric conversion layer is present between an anode and a cathode, and the photoelectric conversion layer contains the photosensor material described in any of [1] to [6]. [8] The photosensor according to [7], wherein the photosensor material is an electron donor material. [9] The photosensor according to [8], wherein the photoelectric conversion layer further contains an electron acceptor material.

[10] A display device having the photosensor according to any of [7] to [9] and an organic light-emitting element, and having the function of detecting biological information using the light of the organic light-emitting element.

[11] The display device according to

[10] , wherein the biological information is fingerprint information.

[12] The display device according to

[10] , wherein the biological information is blood flow information.

[13] A compound having a structure represented by the following general formula (2).

[0014]

[0015] In the above general formula (2), R １４ and R １５ Each is independently selected from the group consisting of a hydrogen atom, an alkyl group, and an aryl group. ３ and Z ４ Each of these atoms is independently selected from the group consisting of carbon atoms, silicon atoms, or germanium atoms.

[0016] The present invention provides an optical sensor material that is sensitive to both green and red light regions and is suitable for vacuum deposition processes.

[0017] The following describes specific embodiments of the present invention, but the present invention is not limited to the embodiments described below and can be implemented with various modifications depending on the purpose and application.

[0018] <Optical Sensor Material> The optical sensor material according to the embodiment of the present invention has a structure represented by the following general formula (1).

[0019]

[0020] In the above general formula (1), R １ ~R ８Each of these is independently selected from the group consisting of a hydrogen atom, alkyl group, cycloalkyl group, aryl group, heteroaryl group, alkoxy group, halogen atom, cyano group, nitro group, silyl group, and boryl group. ９ ~R １２ Each of these is an alkyl group having less than 6 carbon atoms. X is an oxygen atom, a sulfur atom, or a selenium atom. Y １ ~Y ４ Each of them independently, NR １３ Selected from the group consisting of oxygen atoms and sulfur atoms. １３ Z is a hydrogen atom, alkyl group, cycloalkyl group, aryl group, or heteroaryl group. 1 and Z ２ Each of these atoms is independently selected from the group consisting of carbon atoms, silicon atoms, or germanium atoms.

[0021] In all the groups described below, hydrogen may be deuterium. The same applies to the substituents, compounds, or substructures described below.

[0022] In the above general formula (1), R １ ~R ８ Each of these is independently selected from the group consisting of hydrogen atoms, alkyl groups, cycloalkyl groups, aryl groups, heteroaryl groups, alkoxy groups, halogen atoms, cyano groups, nitro groups, silyl groups, and boryl groups.

[0023] Alkyl groups refer to saturated aliphatic hydrocarbon groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, and tert-butyl groups, and may or may not have substituents. The number of carbon atoms in the alkyl group is not particularly limited, but from the viewpoint of availability and cost, it is preferably between 1 and 20, and more preferably between 1 and 8 from the viewpoint of suitability for vacuum deposition processes.

[0024] A cycloalkyl group refers to a saturated alicyclic hydrocarbon group such as a cyclopropyl group, cyclopentyl group, cyclohexyl group, norbornyl group, or adamantyl group, and may or may not have substituents. Examples of substituents include alkyl groups and the groups exemplified as substituents on alkyl groups. The number of ring-forming carbon atoms in the cycloalkyl group is preferably 3 to 20, and more preferably 5 to 10.

[0025] The aryl group refers to aromatic hydrocarbon groups such as phenyl, biphenyl, terphenyl, naphthyl, fluorenyl, benzofluorenyl, dibenzofluorenyl, phenanthryl, anthracenyl, benzophenanthryl, benzoanthracenyl, chrysenyl, pyrenyl, fluoranthenyl, triphenylenyl, benzofluoranthenyl, dibenzoanthracenyl, perilenyl, and hericenyl groups. Among these, phenyl, biphenyl, terphenyl, naphthyl, fluorenyl, phenanthryl, anthracenyl, pyrenyl, fluoranthenyl, and triphenylenyl groups are preferred. The aryl group may or may not have substituents. Examples of substituents include alkyl groups, alkoxy groups, aryloxy groups, amino groups, monoalkylamino groups, dialkylamino groups, monoarylamino groups, diarylamino groups, cyano groups, alkoxycarbonyl groups, halogens, hydroxyl groups, thiol groups, thioalkyl groups, nitro groups, and heteroaryl groups. The number of carbon atoms in the ring-forming aryl group is preferably in the range of 6 to 40, more preferably 6 to 30. In the case of a phenyl group, if there are substituents on two adjacent carbon atoms in the phenyl group, these substituents may form a ring structure with each other. The number of carbon atoms in the aryl group is preferably 6 to 40.

[0026] Heteroaryl groups include, for example, pyridyl, pyrrolyl, furanyl, thiophenyl, quinolinyl, isoquinolinyl, pyrazinyl, pyrimidyl, pyridadinyl, triazinyl, naphthilidinyl, synnolinyl, phthalazinyl, quinoxalinyl, quinazolinyl, benzofuranyl, benzothiophenyl, indolyl, dibenzofuranyl, dibenzothiophenyl, carbazolyl, and benzo This refers to cyclic aromatic groups having one or more non-carbon atoms in the ring, such as carbazolyl, carboninyl, indrocarbazolyl, benzoflocarbazolyl, benzothienocarbazolyl, dihydroindenocarbazolyl, benzoquinolinyl, acridinyl, dibenzoacridinyl, benzimidazolyl, imidazopyridyl, benzoxazolyl, benzothiazolyl, and phenanthrolinyl groups. However, naphthilidinyl refers to any of the following groups: 1,5-naphthilidinyl, 1,6-naphthilidinyl, 1,7-naphthilidinyl, 1,8-naphthilidinyl, 2,6-naphthilidinyl, and 2,7-naphthilidinyl. Heteroaryl groups may or may not have substituents. Examples of substituents include alkyl groups, alkoxy groups, aryloxy groups, amino groups, monoalkylamino groups, dialkylamino groups, monoarylamino groups, diarylamino groups, cyano groups, ester groups, halogens, hydroxyl groups, thiol groups, thioalkyl groups, nitro groups, and aryl groups. The number of carbon atoms in the ring-forming heteroaryl group is preferably in the range of 2 to 40, more preferably 2 to 30. Furthermore, the number of carbon atoms in the heteroaryl group is preferably 2 to 40.

[0027] An alkoxy group refers to a functional group in which an aliphatic hydrocarbon group is bonded via an ether linkage, such as a methoxy group, ethoxy group, or propoxy group, and this aliphatic hydrocarbon group may or may not have substituents. Examples of substituents include those exemplified as substituents on alkyl groups. The number of carbon atoms in the alkoxy group is preferably in the range of 1 to 20.

[0028] Halogen atoms include fluorine, chlorine, bromine, and iodine atoms.

[0029] A silyl group refers to a group to which a substituted or unsubstituted silicon atom is bonded. Examples include alkylsilyl groups such as trimethylsilyl, triethylsilyl, tert-butyldimethylsilyl, propyldimethylsilyl, and vinyldimethylsilyl, and arylsilyl groups such as phenyldimethylsilyl, tert-butyldiphenylsilyl, triphenylsilyl, and trinaphthylsilyl. The substituent on the silicon may be further substituted. The number of carbon atoms in the silyl group is not particularly limited, but is preferably in the range of 1 to 30.

[0030] A boryl group refers to a group to which a substituted or unsubstituted boron atom is bonded. Examples include aryl boryl groups such as diphenylboryl and dinaphthylboryl, alkoxyboryl groups such as dimethoxyboryl, diethoxyboryl, and pinacolatoboryl, and aryloxyboryl groups such as diphenoxyboryl. The substituent on the boron may be further substituted. The number of carbon atoms in the boryl group is not particularly limited, but is preferably in the range of 1 to 30.

[0031] Also, in the above general formula (1), R ９ ~R １２ Each of these is an alkyl group having less than six carbon atoms. An alkyl group having less than six carbon atoms refers to an alkyl group, including substituents, that has less than six carbon atoms. For example, this includes saturated aliphatic hydrocarbon groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, and tert-butyl groups, which may or may not have substituents.

[0032] Y １ ~Y ４ Each of them independently, NR １３ Selected from the group consisting of oxygen atoms and sulfur atoms. １３ These are a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or a heteroaryl group. The hydrogen atom, alkyl group, cycloalkyl group, aryl group, and heteroaryl group are as described above.

[0033] From the standpoint of suitability for vacuum deposition processes, R ９ ~R１２ Each is preferably independently a methyl group or an ethyl group, and from the viewpoint of increasing the sensitivity of the light sensor, R ９ ~R １２ It is more preferable that it be a methyl group.

[0034] Furthermore, X is preferably a sulfur atom from the viewpoint of chemical stability and ease of synthesis.

[0035] Also Y １ ~Y ４ From the viewpoint of chemical stability, electrochemical stability, and high mobility of the generated carriers, it is preferable that the atom is a sulfur atom.

[0036] Z １ and Z ２ Each of these atoms is independently selected from the group consisting of carbon atoms, silicon atoms, and germanium atoms, but from the viewpoint of chemical stability and ease of synthesis, it is preferable that each atom be independently a carbon atom or a silicon atom. １ and Z ２ It is more preferable that all of them are carbon atoms.

[0037] Preferred examples of structures represented by general formula (1) are shown below, but are not limited to these.

[0038]

[0039]

[0040]

[0041]

[0042]

[0043]

[0044]

[0045]

[0046]

[0047]

[0048]

[0049]

[0050]

[0051]

[0052]

[0053]

[0054]

[0055]

[0056]

[0057]

[0058]

[0059]

[0060] Optical sensor materials having the structure represented by general formula (1) can be synthesized by known methods, such as the methods described in non-patent literature such as Organic Electronics, 2012, Vol. 13, p. 2967 and RSC Advances, 2015, Vol. 5, p. 107276, and the methods described in patent literature such as International Publication No. 2011 / 052702 and International Publication No. 2015 / 092909.

[0061] For photosensor materials having the structure represented by general formula (1), it is preferable to further improve purity by removing low-boiling-point components through organic synthesis purification methods such as recrystallization and column chromatography, followed by purification by reduced-pressure heating, commonly known as sublimation purification. The heating temperature in sublimation purification is preferably 350°C or lower, and more preferably 330°C or lower, from the viewpoint of preventing thermal decomposition.

[0062] The purity of the optical sensor material having the structure represented by general formula (1) is preferably 99% by weight or more, from the viewpoint of stabilizing the photoelectric conversion characteristics.

[0063] The optical sensor material according to the embodiment of the present invention may consist only of an optical sensor material having a structure represented by general formula (1), but may also include other photoelectric conversion materials in order to further improve the photoelectric conversion efficiency.

[0064] <Optical Sensor> An optical sensor according to an embodiment of the present invention is an optical sensor that converts light into an electrical signal, wherein a photoelectric conversion layer is present between the anode and the cathode, and the photoelectric conversion layer contains the optical sensor material described above.

[0065] The photoelectric conversion layer preferably contains two or more types of photosensor materials, for example, a combination of a photosensor material having a structure represented by general formula (1) and other photosensor materials. The photosensor materials to be combined are preferably an electron donor material (p-type organic semiconductor) or an electron acceptor material (n-type organic semiconductor), with the electron acceptor material being more preferable. That is, it is preferable that the photosensor material having a structure represented by general formula (1) is the electron donor material, and it is more preferable that the photoelectric conversion layer contains a photosensor material having a structure represented by general formula (1) and an electron acceptor material.

[0066] Examples of electron acceptor materials include 1,4,5,8-naphthalenetetracarboxylic dianehydride (NTCDA), 3,4,9,10-perylenetetracarboxylic dianehydride (PTCDA), 3,4,9,10-perylenetetracarboxylic bisbenzimidazole (PTCBI), N,N'-dioctyl-3,4,9,10-naphthyltetracarboxydiimide (PTCDI-C8H); 2-(4-biphenylyl)-5-(4-t-butylphenyl)-1,3 Examples include oxazole derivatives such as 4-oxadiazole (PBD) and 2,5-di(1-naphthyl)-1,3,4-oxadiazole (BND), triazole derivatives such as 3-(4-biphenylyl)-4-phenyl-5-(4-t-butylphenyl)-1,2,4-triazole (TAZ), phenanthroline derivatives, phosphine oxide derivatives, fullerene compounds, carbon nanotubes (CNTs), and derivatives of poly-p-phenylenevinylene polymers with introduced cyano groups (CN-PPV). Two or more of these may be used.

[0067] Among these, fullerene compounds are preferred because they exhibit high charge separation and electron transfer rates. Examples of fullerene compounds include unsubstituted compounds such as C60, C70, C76, C78, ​​C82, C84, C90, and C94, as well as [6,6]-phenyl C61 butyric acid methyl ester ([6,6]-PCBM), [5,6]-phenyl C61 butyric acid methyl ester ([5,6]-PCBM), [6,6]-phenyl C61 butyric acid hexyl ester ([6,6]-PCBH), [6,6]-phenyl C61 butyric acid dodecyl ester ([6,6]-PCBD), phenyl C71 butyric acid methyl ester (PC70BM), and phenyl C85 butyric acid methyl ester (PC84BM).

[0068] Examples of electron donor materials include oligothiophene compounds such as terthiophene, quarterthiophene, sexithiophene, and octithiophene; phenylene vinylene compounds, p-phenylene compounds, polyfluorene compounds; phthalocyanine derivatives such as compound H2 phthalocyanine (H2Pc), copper phthalocyanine (CuPc), and zinc phthalocyanine (ZnPc); porphyrin derivatives; triarylamine derivatives such as N,N'-diphenyl-N,N'-di(3-methylphenyl)-4,4'-diphenyl-1,1'-diamine (TPD) and N,N'-dinaphthyl-N,N'-diphenyl-4,4'-diphenyl-1,1'-diamine (NPD); and carbazole derivatives such as 4,4'-di(carbazole-9-yl)biphenyl (CBP). Two or more of these may be used.

[0069] The electron donor material and the electron acceptor material have different HOMO-LUMO levels. As described above, by combining a photosensor material having the structure represented by general formula (1) with an organic semiconductor having different HOMO-LUMO levels, the excitons generated by absorbing light undergo efficient charge separation and charge dissociation at the interface between the different materials, thereby increasing the photoelectric conversion efficiency.

[0070] When the photoelectric conversion layer contains two or more types of optical sensor materials, these materials may be mixed in a single layer, or layers containing each optical sensor material may be stacked, but from the viewpoint of rectification, stacking is preferable.

[0071] When layers are stacked, it is preferable that the layer containing the electron donor material is located on the anode side and the layer containing the electron acceptor material is located on the cathode side. Furthermore, when layers are stacked, a mixed layer (i-layer) may be present at the stacking interface. Such a configuration is called a p-i-n structure, where the i-layer primarily handles charge separation, while the p-layer and n-layer primarily handle hole transport and electron transport, respectively, thereby increasing the photoelectric conversion efficiency.

[0072] If mixed, it is preferable that the material combined with the photosensor material having the structure represented by general formula (1) is either molecularly compatible or in phase separation at the nanoscale. If in phase separation, the domain size of the phase separation structure is preferably 1 nm to 50 nm.

[0073] The thickness of the photoelectric conversion layer is preferably 10 nm to 500 nm, and more preferably 20 nm to 100 nm. If the photoelectric conversion layer has a laminated structure, the thickness of the layer containing the photoelectric conversion material having the structure represented by general formula (1) and the thickness of the laminated layer are preferably 5 nm to 495 nm, and more preferably 10 nm to 50 nm, out of the total thickness of the photoelectric conversion layer. If there is a mixed layer (i layer) at the laminated interface, the thickness of the i layer is preferably 1 nm to 100 nm, and more preferably 5 nm to 50 nm.

[0074] In optical sensors, it is preferable that the anode and / or cathode have light transmittance. The light transmittance of the electrodes is not particularly limited as long as incident light reaches the photoelectric conversion layer and generates an electrical signal. Here, light transmittance is defined as [transmitted light intensity (W / m²)]. ２ ) / incident light intensity (W / m ２This index is derived from a value calculated by multiplying by 100 (%) (this is called "light transmittance"). In this invention, it is preferable that the light transmittance at wavelengths of 350 nm or higher be 50% or higher, more preferably 70% or higher, and even more preferably 90% or higher. The thickness of the light-transmitting electrode can be within the range of having both light transmittance and conductivity, and varies depending on the electrode material, but is preferably 20 nm to 300 nm. The other electrode does not necessarily need to be light-transmitting as long as it is conductive, and its thickness is not particularly limited.

[0075] When it comes to the materials used for the electrodes, it is preferable to use a conductive material with a large work function for one electrode and a conductive material with a small work function for the other electrode.

[0076] When electrodes are fabricated from different materials, it is preferable to use an electrode made from a conductive material with a high work function as the anode. Suitable conductive materials with a high work function include, for example, metals such as gold, platinum, chromium, and nickel, as well as transparent metal oxides such as indium, tin, and molybdenum, and composite metal oxides such as indium tin oxide (ITO) and indium zinc oxide (IZO).

[0077] Here, it is preferable that the conductive material used for the anode is ohmic bonded with the photoelectric conversion layer. Furthermore, as will be described later, when a hole transport layer is provided between the anode and the photoelectric conversion layer, it is preferable that the conductive material used for the anode is ohmic bonded with the hole transport layer.

[0078] The method for forming the anode can be selected according to the material being formed, but examples include sputtering, vapor deposition, and inkjet. For example, sputtering is preferred when forming the anode with a metal oxide, and vapor deposition is preferred when forming the anode with a metal.

[0079] When electrodes are fabricated using different materials, it is preferable to use an electrode made of a conductive material with a low work function as the cathode. Suitable conductive materials with a low work function include, for example, alkali metals such as lithium, alkaline earth metals such as magnesium and calcium, tin, silver, aluminum, and alloys thereof. Laminates using two or more of these materials may also be used.

[0080] Here, it is preferable that the conductive material used for the cathode forms an ohmic junction with the photoelectric conversion layer. Furthermore, as will be described later, when an electron transport layer is provided between the cathode and the photoelectric conversion layer, it is preferable that the conductive material used for the cathode forms an ohmic junction with the electron transport layer. In addition, it is possible to improve the extracted current by introducing a metallic fluoride such as lithium fluoride or cesium fluoride at the interface between the cathode and the electron transport layer.

[0081] The method for forming the cathode can be selected according to the material being formed, but examples include sputtering, vapor deposition, and inkjet. For example, sputtering is preferred when forming the cathode with a metal oxide, and vapor deposition is preferred when forming the anode with a metal.

[0082] To maintain the mechanical strength of the optical sensor, suppress thermal deformation, and provide a barrier that prevents water vapor and oxygen from entering the photoelectric conversion layer, it is preferable to form the optical sensor on a substrate. Examples of substrates include glass plates, ceramic plates, resin films, varnished resin films, and thin metal plates. Among these, glass substrates are preferably used because they are transparent and easy to process. Furthermore, flexible displays and foldable displays are increasing, mainly in mobile devices such as smartphones, and resin films and resin films are suitable for these applications, such as heat-resistant films like polyimide films and polyethylene naphthalate films.

[0083] In the optical sensor according to the embodiment of the present invention, a hole transport layer may be provided between the anode and the photoelectric conversion layer. Examples of materials for forming the hole transport layer include the above-mentioned oligothiophene compounds, phenylene vinylene compounds, p-phenylene compounds, polyfluorene compounds, phthalocyanine derivatives such as H2 phthalocyanine (H2Pc), copper phthalocyanine (CuPc), and zinc phthalocyanine (ZnPc), porphyrin derivatives, triarylamine derivatives such as N,N'-diphenyl-N,N'-di(3-methylphenyl)-4,4'-diphenyl-1,1'-diamine (TPD) and N,N'-dinaphthyl-N,N'-diphenyl-4,4'-diphenyl-1,1'-diamine (NPD), carbazole derivatives such as 4,4'-di(carbazole-9-yl)biphenyl (CBP), and metal oxides exhibiting p-type semiconductivity such as molybdenum oxide and tungsten oxide. The thickness of the hole transport layer is preferably 1 nm to 200 nm, and more preferably 5 nm to 100 nm.

[0084] Furthermore, the optical sensor according to the embodiment of the present invention may have a hole extraction layer between the anode and the hole transport layer. Examples of materials for forming the hole extraction layer include charge transfer complexes such as tris(4-bromophenyl)aminium hexachloroantimonate (TBPAH), 1,4,5,8,9,11-hexaazatriphenylene-hexacarbonnitrile (HAT-CN6), 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ), tetracyanoquinodimethane derivatives, radialene derivatives, and fluorinated copper phthalocyanine.

[0085] Furthermore, the optical sensor according to the embodiment of the present invention may have an electron transport layer between the photoelectric conversion layer and the cathode. Examples of materials for forming the electron transport layer include, in addition to the n-type organic semiconductor described above, polycyclic aromatic derivatives, styryl aromatic ring derivatives, quinone derivatives, phosphorus oxide derivatives, quinolinol complexes such as tris(8-quinolinolate)aluminum(III), benzoquinolinol complexes, hydroxyazole complexes, azomethine complexes, tropolone metal complexes, and flavonol metal complexes.

[0086] From the viewpoint of further improving electron transport efficiency, it is preferable to use a compound having a heteroaryl group containing electron-accepting nitrogen in the electron transport layer. Here, electron-accepting nitrogen refers to a nitrogen atom that forms a multiple bond with an adjacent atom. Heteroaryl groups containing electron-accepting nitrogen have a high electron affinity, making it easier to transport electrons and contributing to a greater improvement in photoelectric conversion efficiency.

[0087] Examples of compounds having a heteroaryl group structure containing electron-accepting nitrogen include pyridine derivatives, triazine derivatives, pyrazine derivatives, pyrimidine derivatives, quinoline derivatives, quinoxaline derivatives, quinazoline derivatives, naphthyridine derivatives, benzoquinoline derivatives, phenanthroline derivatives, imidazole derivatives, oxazole derivatives, thiazole derivatives, triazole derivatives, oxadiazole derivatives, thiadiazole derivatives, benzimidazole derivatives, benzoxazole derivatives, benzthiazole derivatives, phenanthroimidazole derivatives, and oligopyridine derivatives such as bipyridine and terpyridine. Two or more of these may be used.

[0088] Furthermore, it is more preferable if the electron transport material has a condensed polycyclic aromatic skeleton because the glass transition temperature is improved and the electron mobility is increased. Preferred condensed polycyclic aromatic skeletons include quinolinol complexes, triazine derivatives, fluorantene skeletons, anthracene skeletons, pyrene skeletons, or phenanthroline skeletons.

[0089] The electron transport layer may contain an electron donor material. Here, the electron donor material is a compound that improves the electrical conductivity of the electron transport layer. Preferred examples of electron donor materials include alkali metals such as Li, inorganic salts containing alkali metals such as LiF, complexes of alkali metals and organic substances such as lithium quinolinol, alkaline earth metals, inorganic salts containing alkaline earth metals, complexes of alkaline earth metals and organic substances, rare earth metals such as Eu and Yb, inorganic salts containing rare earth metals, and complexes of rare earth metals and organic substances. Two or more of these may be used. Among these, metallic lithium, rare earth metals, and lithium quinolinol (Liq) are preferred.

[0090] The thickness of the electron transport layer is preferably 1 nm to 200 nm, and more preferably 5 nm to 100 nm.

[0091] The formation method for each of the above layers constituting the optical sensor may be either a dry process or a wet process, and examples include resistance heating deposition, electron beam deposition, sputtering, molecular stacking, coating, inkjet, and printing. Among these, resistance heating deposition is preferred from the viewpoint of device characteristics.

[0092] The optical sensor according to an embodiment of the present invention has the function of converting light into an electrical signal. In the optical sensor according to an embodiment of the present invention, from the viewpoint of efficiently converting green light and red light of different wavelengths into electrical signals, it is preferable that the absorption peak wavelength of the photoelectric conversion layer is 450 nm or more and 700 nm or less, and the full width at half maximum is 100 nm or more and 400 nm or less, and it is more preferable that the absorption peak wavelength is 500 nm or more and 660 nm or less, and the full width at half maximum is 120 nm or more and 300 nm or less.

[0093] The optical sensor according to the embodiment of the present invention can be applied to various electronic devices and optical sensing devices by utilizing its function of simultaneously and efficiently converting green light and red light into photoelectric energy. For example, it can be used as a biosensor, optical switch, or image sensor, and can acquire biological information such as fingerprints, veins, pulse waves, and blood oxygen concentration with high sensitivity.

[0094] The biological information used in this invention is not particularly limited as long as it is information obtained from a living organism, but examples include information obtained as reflected or transmitted light when light is shone on a living organism, and information obtained as light emitted from a living organism. In addition to the aforementioned fingerprints, veins, pulse waves, and blood oxygen saturation, other objects to be measured include, for example, the iris, facial shape, skin dryness, and blood glucose levels.

[0095] Furthermore, in recent years, many communication devices with display functions, such as mobile phones and tablet terminals, have incorporated biometric authentication functions to improve security. In this context, the optical sensor of the present invention is preferably used as a fingerprint authentication device for a display device. One embodiment of this invention involves combining the optical sensor according to an embodiment of the present invention with an organic light-emitting element, and incorporating it into a display device that performs fingerprint authentication using the light from the organic light-emitting element. For example, by configuring a portion of the pixels of an organic EL display that displays in a matrix and / or segment manner with the photoelectric conversion element of the present invention, a fingerprint authentication function can be added to the organic EL display.

[0096] As described above, the optical sensor according to the embodiment of the present invention has excellent photoelectric conversion characteristics for green light and red light, so by using it in combination with green and red light sources, it is possible to perform sensing with high accuracy and sensitivity.

[0097] For example, by receiving and photoelectrically converting the light emitted from the organic light-emitting element of an organic EL display, which is reflected and scattered by a finger touching the display, via a color filter using an optical sensor according to an embodiment of the present invention, fingerprint information can be acquired with high accuracy.

[0098] Furthermore, by configuring a portion of the pixels of the organic EL display with the optical sensor according to the embodiment of the present invention, as described above, a biosensing function can be added to the organic EL display. That is, by receiving and photoelectrically converting the light absorbed and scattered by a finger touching the display, which is emitted from the organic light-emitting element of the organic EL display, via a color filter using the optical sensor of the present invention, biological information such as veins, pulse waves, and blood oxygen concentration can be acquired with high precision.

[0099] Furthermore, as an embodiment of the present invention, a preferred embodiment of the above general formula (1) is the general formula (1a) shown below, and as an embodiment of the present invention, a compound having the structure represented by the general formula (2) shown below is mentioned. Among these, a compound having the structure represented by formula (2a) is preferred.

[0100]

[0101] In the above general formula (1a), R １ ~R ８ Each of these is independently selected from the group consisting of a hydrogen atom, alkyl group, cycloalkyl group, aryl group, heteroaryl group, alkoxy group, halogen atom, cyano group, nitro group, silyl group, and boryl group. ９ ~R １２ Each of these is an alkyl group having less than 6 carbon atoms. X is an oxygen atom, a sulfur atom, or a selenium atom. Y １ ~Y ４ Each of them independently, NR １３ Selected from the group consisting of oxygen atoms and sulfur atoms. １３ R is a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or a heteroaryl group. In the above general formula (2), １４ and R １５ Each is independently selected from the group consisting of a hydrogen atom, an alkyl group, and an aryl group. ３ and Z ４ Each of these atoms is independently selected from the group consisting of carbon atoms, silicon atoms, or germanium atoms.

[0102] The compound represented by the above general formula (2) is a material that has deposition stability and high photoelectric conversion properties, and can be used not only in the photosensors described above, but also in applications such as organic light-emitting elements, organic transistors, organic thin-film solar cells, and biosensors.

[0103] The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

[0104] First, the evaluation methods for each example and comparative example are described below.

[0105] ( １ (H-NMR) The optical sensor materials obtained in each example were subjected to a deuterated chloroform solution using a superconducting FT-NMR JNM-ECZ400R (manufactured by JEOL Ltd.). １ The chemical structure was identified by performing 1H-NMR measurements.

[0106] (Thin Film Absorption Characteristics) A 3 cm square quartz plate was surface-cleaned for 20 minutes using a UV ozone cleaning machine (manufactured by Sen Special Light Source). Subsequently, the photosensor materials obtained in each example were deposited using a vapor deposition machine at a deposition rate of 1 nm / s to produce thin films with a thickness of 30 nm. The absorption spectra of the obtained thin films were measured using a spectrophotometer (U-3010) manufactured by Hitachi High-Tech Science Co., Ltd., and the peak wavelength and full width at half maximum were determined.

[0107] (Measurement of external quantum efficiency and spectral sensitivity peak) For the photosensors obtained in each example and comparative example, monochromatic light was irradiated from the glass substrate side in air at wavelengths from 400 nm to 700 nm at 2 nm intervals, and the external quantum efficiency and spectral sensitivity peak wavelength at -3 V were measured using a spectral sensitivity measuring device (Hyper Monolight System, SM-250, manufactured by Spectrometer Co., Ltd.).

[0108] (Example 1) Synthesis of Compound A-1

[0109]

[0110] All of the following reactions were carried out under a nitrogen atmosphere, and compound A-1B was synthesized based on previously published literature (Journal of Materials Chemistry A, 2020, Vol. 8, p. 5194).

[0111] Compound A-1B (2.00 g, 9.7 mmol) was dissolved in tetrahydrofuran (40 mL) and cooled to -78°C. A 1.6 M hexane solution of n-butyllithium (7.3 mL, 11.7 mmol) was slowly added dropwise, and the mixture was stirred at -78°C for 1 hour. Then, tributyltin chloride (3.2 mL, 11.7 mmol) was slowly added dropwise, and the mixture was stirred at -78°C for a further 30 minutes. After raising the temperature to room temperature overnight, water was added to quench the reaction solution, and it was extracted with ethyl acetate. The resulting ethyl acetate solution was washed with water and saturated brine and dried over magnesium sulfate. After removing the solid by vacuum filtration, the solution was concentrated using an evaporator to obtain 5.57 g of compound A-1C as a purple liquid. Compound A-1C contained by-products, but it was used in the next step without further purification.

[0112] Compound A-1C (5.57 g), compound A-1D (1.10 g, 3.7 mmol), and tetrakistriphenylphosphine palladium (0) (433 mg, 0.37 mmol) obtained above were dissolved in toluene (50 mL) and stirred under reflux conditions for 6 hours. After the reaction solution was cooled to room temperature, the insoluble solid was removed by vacuum filtration. The obtained filtrate was extracted with methylene chloride and then washed with water and saturated brine. The obtained solution was dried over magnesium sulfate, the solid was removed by vacuum filtration, and the solution was concentrated using an evaporator. Subsequently, it was purified by silica gel column chromatography (silica gel / anhydrous potassium carbonate weight ratio 10 / 1, developing solvent: methylene chloride / heptane volume ratio 1 / 4). By washing the obtained solid with heptane, 1.50 g of compound A-1 was obtained as a blackish-purple solid (74% yield based on compound A-1D).

[0113] The obtained compound A-1 １ The results of the 1H-NMR analysis are as follows, confirming that the blackish-purple powder obtained above is compound A-1. １ H-NMR (CDCl ３ (δ / ppm)): 8.11 (s, 2H), 7.85 (s, 2H), 7.23 (d, 2H), 7.04 (d, 2H), 1.56 (s, 12H).

[0114] To further increase the purity, sublimation purification was performed. A tantalum boat containing compound A-1 was placed in a glass tube, and an oil diffusion pump was used to extract 3.0 × 10⁻⁶ of the compound. －３ The compound was sublimated by heating at 260°C under Pa pressure. The solid adhering to the glass tube wall was collected and analyzed by LC-MS, revealing a purity of 99.8%. The thin-film absorption characteristics of compound A-1 after sublimation purification were evaluated using the method described above, and the results are shown below. Absorption spectrum (thin film): λmax: 574 nm, full width at half maximum: 156 nm.

[0115] (Fabrication of the optical sensor) Next, an optical sensor was fabricated using compound A-1. A 46 mm x 38 mm transparent glass substrate with an ITO electrode layer having a thickness of 125 nm was prepared as the anode. This substrate was immersed in pure water and ultrasonically cleaned for 10 minutes, then ultrasonically cleaned with isopropyl alcohol for 10 minutes and thoroughly dried. After that, UV ozone cleaning was performed for 20 minutes.

[0116] Next, a solution of poly-3,4-ethylenedioxythiophene (PEDOT:PSS) doped with poly-4-styrene sulfonic acid and isopropyl alcohol mixed in a volume ratio of 6:4 was spin-coated onto the ITO electrode layer of the substrate at 3,000 rpm for 30 seconds, and then heated on a hot plate at 150°C for 10 minutes to form a hole extraction layer with a thickness of 55 nm.

[0117] A substrate with a hole extraction layer formed on it is placed in a vacuum deposition apparatus (manufactured by Eiko Engineering Co., Ltd.) and approximately 3 x 10 －３ The pressure was reduced to Pa. N-[1,1'-biphenyl]-4-yl-9,9-dimethyl-N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]-9H-fluoren-2-amine (60 nm) was deposited on the hole extraction layer as a hole transport layer to form a hole transport layer. Next, compound A-1 (23 nm) was used as a p-type organic semiconductor, and fullerene (C) was used as an n-type organic semiconductor. ６０ A photoelectric conversion layer was formed by depositing (23 nm) and (23 nm) respectively.

[0118] After opening the vacuum deposition apparatus to the atmosphere, the deposition source is replaced, and then the deposition is repeated for approximately 3 x 10⁻⁶ times. －３The pressure was reduced to Pa. Lithium quinolinol (7.5 nm) and aluminum (approximately 70 nm) were sequentially deposited on the photoelectric conversion layer to form the electron transport layer and cathode, respectively.

[0119] The obtained photosensor was subjected to thin-film absorption characteristics, external quantum efficiency, and spectral sensitivity peak measurements using the method described above. The external quantum efficiency at 530 nm for green light was 10.1%, and the external quantum efficiency at 630 nm for red light was 9.8%, indicating sensitivity to both green and red light. Furthermore, the external quantum efficiency at the spectral sensitivity peak wavelength of 586 nm was 11.9%.

[0120] (Example 2) Synthesis of Compound A-2

[0121]

[0122] All of the following reactions were carried out under a nitrogen atmosphere. Compound A-2A was synthesized from compound A-1A, with the exception of using iodoethane instead of bromoethane as the reaction reagent, based on previously published literature (Dies and Pigments, 2012, Vol. 92, p. 1292).

[0123] Compound A-2A (2.55 g, 10.9 mmol) was dissolved in tetrahydrofuran (40 mL) and cooled to -78°C. A 1.6 M hexane solution of n-butyllithium (8.1 mL, 13.0 mmol) was slowly added dropwise, and the mixture was stirred at -78°C for 1 hour. Then, tributyltin chloride (3.5 mL, 13.7 mmol) was slowly added dropwise, and the mixture was stirred at -78°C for a further 30 minutes. After raising the temperature to room temperature overnight, water was added to quench the reaction solution, and it was extracted with ethyl acetate. The resulting ethyl acetate solution was washed with water and saturated brine and dried over magnesium sulfate. After removing the solid by vacuum filtration, the solution was concentrated using an evaporator to obtain 6.40 g of compound A-2B as a purple liquid. Compound A-2B contained by-products, but it was used in the next step without further purification.

[0124] Compound A-2B (6.40 g), compound A-1D (1.02 g, 3.5 mmol), and tetrakistriphenylphosphine palladium (0) (401 mg, 0.35 mmol) obtained above were dissolved in toluene (50 mL) and stirred under reflux conditions for 4 hours. After the reaction solution was cooled to room temperature, it was diluted with methylene chloride and subjected to short-pass silica gel column chromatography (silica gel / anhydrous potassium carbonate weight ratio 10 / 1). The distillate was concentrated and further purified by silica gel column chromatography (silica gel / anhydrous potassium carbonate weight ratio 10 / 1, developing solvent: methylene chloride / heptane volume ratio 1 / 5). The obtained solid was washed with methanol to obtain 1.80 g of compound A-2 as a blackish-purple solid (yield 87% based on compound A-1D).

[0125] The obtained compound A-2 １ The results of the 1H-NMR analysis are as follows, confirming that the blackish-purple powder obtained above is compound A-2. １ H-NMR (CDCl ３ (δ / ppm)): 8.06 (s, 2H), 7.85 (s, 2H), 7.25 (d, 2H), 6.98 (d, 2H), 2.04-1.96 (m, 8H) 0.68 (t, 12H).

[0126] To further increase the purity, sublimation purification was performed. A tantalum boat containing compound A-2 was placed in a glass tube, and an oil diffusion pump was used to extract 3.0 × 10⁻⁶ of the compound. －３ The compound was sublimated by heating at 280°C under Pa pressure. The solid adhering to the glass tube wall was collected and analyzed by LC-MS, revealing a purity of 99.2%. The thin-film absorption characteristics of compound A-2 after sublimation purification were evaluated using the method described above, and the results are shown below. Absorption spectrum (thin film): λmax: 584 nm, full width at half maximum: 145 nm.

[0127] A photosensor prepared in the same manner as in Example 1, except that compound A-2 was used instead of compound A-1 as the p-type organic semiconductor, was measured using the method described above. The external quantum efficiency at 530 nm for green light was 4.3%, and the external quantum efficiency at 630 nm for red light was 5.2%, showing sensitivity to both green and red light. Furthermore, the external quantum efficiency at the spectral sensitivity peak wavelength of 606 nm was 5.4%.

[0128] (Example 3) Synthesis of Compound A-3

[0129]

[0130] All of the following reactions were carried out under a nitrogen atmosphere. Compound A-3B was synthesized from compound A-3A, based on previously published literature (ACS Applied Energy Materials, 2019, Vol. 2, p. 5600).

[0131] Compound A-3B (1.95 g, 8.8 mmol) was dissolved in tetrahydrofuran (40 mL) and cooled to -78°C. A 1.6 M hexane solution of n-butyllithium (6.6 mL, 10.6 mmol) was slowly added dropwise, and the mixture was stirred at -78°C for 1 hour. Then, tributyltin chloride (2.9 mL, 10.6 mmol) was slowly added dropwise, and the mixture was stirred at -78°C for a further 30 minutes. After raising the temperature to room temperature overnight, water was added to quench the reaction solution, and it was extracted with ethyl acetate. The resulting ethyl acetate solution containing the target compound was washed with water and saturated brine, and dried over magnesium sulfate. After removing the solid by vacuum filtration, the solvent was removed by distillation to obtain 5.29 g of compound A-3C as a brown liquid. Compound A-3C contained by-products, but it was used in the next step without further purification.

[0132] Compound A-3C (5.29 g), compound A-1D (882 mg, 3.0 mmol), and tetrakistriphenylphosphine palladium (0) (347 mg, 0.30 mmol) obtained above were dissolved in toluene (40 mL) and stirred under heating reflux conditions for 5 hours. After cooling the reaction solution, it was diluted with methylene chloride and purified by short-pass silica gel column chromatography (developing solvent: methylene chloride / heptane volume ratio 1 / 2). After concentrating the distillate, it was purified again by silica gel column chromatography (silica gel / anhydrous potassium carbonate weight ratio 10 / 1, developing solvent: methylene chloride / heptane volume ratio starting from 1 / 5 and ending at 1 / 4). The recovered solid was washed with methanol to obtain 916 mg of compound A-3 as a blackish-purple solid (yield 53% based on compound A-1D).

[0133] The obtained compound A-3 １ The results of the 1H-NMR analysis are as follows, confirming that the blackish-purple powder obtained above is compound A-3. １ H-NMR (CDCl ３ (δ / ppm): 8.15 (s, 2H), 7.86 (s, 2H), 7.28 (d, 2H), 7.13 (d, 2H), 0.49 (s, 2H) Sublimation purification was performed to further increase the purity. A tantalum boat containing compound A-3 was placed in a glass tube, and an oil diffusion pump was used to extract 2.8 × 10⁻¹⁶ －３ The compound A-3 was sublimated by heating at 280°C under Pa pressure. Compound A-3, which adhered to the glass tube wall, was recovered and analyzed by LC-MS, revealing a purity of 98.8%. The thin-film absorption characteristics of compound A-3 after sublimation purification were evaluated using the method described above, and the results are shown below. Absorption spectrum (thin film): λmax: 554 nm, full width at half maximum: 148 nm.

[0134] Except for using compound A-3 instead of compound A-1 as the p-type organic semiconductor, the photosensor was measured using the same method as in Example 1, and the external quantum efficiency at 530 nm for green light was 8.4%, and the external quantum efficiency at 630 nm for red light was 4.8%, showing sensitivity to both green and red light. Furthermore, the external quantum efficiency at the spectral sensitivity peak wavelength of 554 nm was 8.7%.

[0135] (Example 4) Synthesis of Compound A-4

[0136]

[0137] All of the following reactions were carried out under a nitrogen atmosphere, and the synthesis method for compound A-1B was the same as that described in Example 1.

[0138] Compound A-1B (3.00 g, 14.5 mmol) was dissolved in tetrahydrofuran (50 mL) and cooled to -78°C. A 1.6 M hexane solution of n-butyllithium (10.4 mL, 16.7 mmol) was slowly added dropwise, and the temperature was raised to -30°C and stirred for 1 hour. Then, it was cooled again to -78°C, and tributyltin chloride (4.5 mL, 16.7 mmol) was slowly added dropwise, and the mixture was stirred at -78°C for a further 30 minutes. After raising the temperature to room temperature overnight, methanol and water were sequentially added to quench the reaction solution, and it was extracted with ethyl acetate. The resulting ethyl acetate solution containing the target compound was washed with water and saturated brine and dried over magnesium sulfate. After removing the solid by vacuum filtration, the solution was distilled off to obtain compound A-1C as a yellowish-brown liquid. Compound A-1C contained by-products, but it was used in the next step without further purification.

[0139] The entire amount of compound A-1C obtained above, bromobenzene (2.3 mL, 21.8 mmol), and tetrakistriphenylphosphine palladium (0) (841 mg, 0.73 mmol) were dissolved in toluene (50 mL), and the mixture was stirred under reflux conditions for 2.5 hours. After the reaction solution was cooled to room temperature, the insoluble solid was removed by vacuum filtration. The obtained filtrate was concentrated, methanol was added to precipitate, and the precipitated orange solid was removed by vacuum filtration. The filtrate was concentrated and purified by silica gel column chromatography (eluent: heptane) to obtain 2.10 g of compound A-4A as a pale yellow liquid (yield 51% relative to compound A-1B).

[0140] Compound A-4A (2.10 g, 7.4 mmol) was dissolved in tetrahydrofuran (50 mL) and cooled to -78°C. A 1.6 M hexane solution of n-butyllithium (5.6 mL, 8.9 mmol) was slowly added dropwise, and the temperature was raised to -30°C and stirred for 1 hour. Then, it was cooled again to -78°C, and tributyltin chloride (2.4 mL, 8.9 mmol) was slowly added dropwise, and the mixture was stirred at -78°C for a further 30 minutes. After raising the temperature to room temperature overnight, methanol and water were sequentially added to quench the reaction solution, and it was extracted with ethyl acetate. The resulting ethyl acetate solution containing the target compound was washed with water and saturated brine and dried over magnesium sulfate. After removing the solid by vacuum filtration, the solution was distilled off to obtain compound A-4B as a yellowish-brown liquid. Compound A-4B contains by-products, but it was used in the next step without further purification.

[0141] The entire amount of compound A-4B obtained above, compound A-1D (1.04 g, 3.5 mmol), and tetrakistriphenylphosphine palladium (0) (409 mg, 0.35 mmol) were dissolved in toluene (50 mL) and stirred under reflux conditions for 5 hours. After the reaction solution was cooled to room temperature, it was diluted with chloroform and the insoluble solid was removed by vacuum filtration. The obtained filtrate was concentrated, methanol was added to precipitate, and the precipitate was recovered by vacuum filtration. This was dissolved in methylene chloride and purified by short-pass chromatography using silica gel column chromatography (eluent: methylene chloride). The solid obtained by concentrating the solution was heated twice in a toluene / heptane mixed solvent system and then washed with methanol to obtain 2.19 g of compound A-4 as a blackish-purple solid (89% yield based on compound A-1D).

[0142] The obtained compound A-4 １ The results of the 1H-NMR analysis are as follows, confirming that the blackish-purple powder obtained above is compound A-4. １ H-NMR (CDCl ３(δ / ppm): 8.12 (s, 2H), 7.85 (s, 2H), 7.65–7.62 (m, 4H), 7.41–7.37 (m, 4H), 7.30–7.25 (m, 4H, partially overlapping with peaks derived from chloroform), 1.60 (s, 12H). Sublimation purification was performed to further increase the purity. A tantalum boat containing compound A-4 was placed in a glass tube, and an oil diffusion pump was used to extract 7.0 × 10⁻⁶ of the compound. －３ The compound was sublimated by heating at 310°C under Pa pressure. The solid adhering to the glass tube wall was recovered and analyzed by LC-MS, revealing a purity of 97.2%. The results of the thin-film absorption characteristics evaluation of compound A-4 after sublimation purification using the method described above are shown below. The results of the thin-film absorption characteristics evaluation of compound A-4 after sublimation purification using the method described above are shown below. Absorption spectrum (thin film): λmax: 598 nm, full width at half maximum: 177 nm.

[0143] A photosensor prepared in the same manner as in Example 1, except that compound A-4 was used instead of compound A-1 as the p-type organic semiconductor, was measured using the method described above. The external quantum efficiency at 530 nm for green light was 4.5%, and the external quantum efficiency at 630 nm for red light was 6.1%, showing sensitivity to both green and red light. Furthermore, the external quantum efficiency at the spectral sensitivity peak wavelength of 610 nm was 6.1%.

[0144] (Example 5) Compound A-4 was used instead of compound A-1 as the p-type organic semiconductor, and fullerene (C) was used as the n-type organic semiconductor. ６０ A photosensor was fabricated in the same manner as in Example 1, except that a dicyanovinyl compound C-1 synthesized based on publicly available literature (Cryst. Growth Des. 2010, Vol. 10, p. 5027) was used instead of ). When evaluated using the same method, the external quantum efficiency at 530 nm for green light was 5.1%, and the external quantum efficiency at 630 nm for red light was 5.6%, showing sensitivity to both green and red light. Furthermore, the external quantum efficiency at the spectral sensitivity peak wavelength of 614 nm was 5.7%, showing sensitivity to both green and red light.

[0145]

[0146] (Example 6) Synthesis of Compound A-5

[0147]

[0148] All of the following reactions were carried out under a nitrogen atmosphere.

[0149] The synthesis method for compound A-1C was exactly the same as in Example 4, using compound A-1B (3.00 g, 14.5 mmol) as the starting material, and the entire amount, including the by-product, was used in the following reaction.

[0150] The entire amount of compound A-1C, 1-bromo-4-tert-butylbenzene (3.7 mL, 21.8 mmol), and tetrakistriphenylphosphine palladium (0) (840 mg, 0.73 mmol) were dissolved in toluene (50 mL), and the mixture was stirred under reflux conditions for 4 hours. After the reaction solution was cooled to room temperature, the insoluble solid was removed by vacuum filtration. The obtained filtrate was concentrated and purified by silica gel column chromatography (eluent: heptane), and washed with methanol to obtain 2.45 g of compound A-5A as a pale yellow solid (50% yield relative to compound A-1B).

[0151] Compound A-5A (2.32 g, 6.9 mmol) was dissolved in tetrahydrofuran (40 mL) and cooled to -78°C. A 1.6 M hexane solution of n-butyllithium (5.1 mL, 8.2 mmol) was slowly added dropwise, and the temperature was raised to -30°C and stirred for 1 hour. Then, it was cooled again to -78°C, and tributyltin chloride (2.2 mL, 8.2 mmol) was slowly added dropwise, and the mixture was stirred at -78°C for a further 30 minutes. After raising the temperature to room temperature overnight, methanol and water were sequentially added to quench the reaction solution, and it was extracted with ethyl acetate. The resulting ethyl acetate solution containing the target compound was washed with water and saturated brine and dried over magnesium sulfate. After removing the solid by vacuum filtration, the solution was distilled off to obtain compound A-5B as a yellowish-brown liquid. Compound A-5B contains by-products, but it was used in the next step without further purification.

[0152] The total amount of Compound A-5B obtained above, Compound A-1D (960 mg, 3.3 mmol), and tetrakis(triphenylphosphine)palladium(0) (377 mg, 0.33 mmol) were dissolved in toluene (50 mL), and stirred under heating reflux conditions for 5 hours. After the reaction solution was cooled to room temperature, it was diluted with chloroform and insoluble solids were removed by filtration under reduced pressure. The obtained filtrate was concentrated, methanol was added to precipitate a precipitate, and the precipitate was recovered by filtration under reduced pressure. This was dissolved in chloroform and subjected to short-path purification by silica gel column chromatography (developing solvent: chloroform). The solid obtained by concentrating the solution was recrystallized in a mixed solvent system of toluene / heptane / isopropanol and then washed with methanol to obtain 2.14 g of Compound A-5 as a black-purple solid (yield 81% based on Compound A-1D).

[0153] The obtained Compound A-5 １ The analysis results of 1H-NMR were as follows, confirming that the black-purple powder obtained above was Compound A-5. １ 1H-NMR (CDCl ３ (δ / ppm)): 8.12 (s, 2H), 7.84 (s, 2H), 7.56 (d, 4H), 7.41 (d, 4H), 7.24 (s, 2H), 1.59 (s, 12H), 1.36 (s, 18H). Further, sublimation purification was performed to increase the purity. The tantalum boat containing Compound A-5 was placed in a glass tube, and heated and sublimated at 340 °C under a pressure of 1.3 × 10 －２ Pa. The Compound A-5 adhering to the glass tube wall was recovered and analyzed by LC-MS, and the purity was 96.2%. The results of evaluating the thin film absorption characteristics of Compound A-5 after sublimation purification by the above-mentioned method are shown below. Absorption spectrum (thin film): λmax: 593 nm, full width at half maximum: 176 nm.

[0154] A photosensor fabricated using the same method as in Example 1, except that compound A-5 was used instead of compound A-1 as the p-type organic semiconductor, was measured using the method described above. The external quantum efficiency at 530 nm for green light was 3.3%, and the external quantum efficiency at 630 nm for red light was 3.7%, indicating sensitivity to both green and red light. Furthermore, the external quantum efficiency at the spectral sensitivity peak wavelength of 636 nm was 3.7%.

[0155] (Example 7) Compound A-5 was used instead of compound A-1 as the p-type organic semiconductor, and fullerene (C) was used as the n-type organic semiconductor. ６０ A photosensor was fabricated in the same manner as in Example 1, except that dicyanovinyl compound C-1 was used instead of ). When evaluated using the same method, the external quantum efficiency at 530 nm for green light was 3.4%, and the external quantum efficiency at 630 nm for red light was 2.1%, showing sensitivity to both green and red light. Furthermore, the external quantum efficiency at the spectral sensitivity peak wavelength of 524 nm was 3.4%.

[0156] (Example 8) Synthesis of Compound A-6

[0157]

[0158] All of the following reactions were carried out under a nitrogen atmosphere.

[0159] Compound A-1C was synthesized using compound A-1B (2.00 g, 9.7 mmol) as a starting material in the same manner as in Example 1, and the entire amount, including the by-product, was used in the following reaction.

[0160] The entire amount of compound A-1C, 2-bromotoluene (1.8 mL, 14.5 mmol), and dichlorobis(triphenylphosphine)palladium(II) (370 mg, 0.48 mmol) were dissolved in dioxane (50 mL), and the mixture was stirred under reflux conditions for 3 hours. After the reaction solution was cooled to room temperature, the insoluble solid was removed by vacuum filtration. The obtained filtrate was concentrated and then purified by silica gel column chromatography (eluent: heptane) to obtain 2.23 g of compound A-6A as a pale yellow liquid (77% yield relative to compound A-1B).

[0161] Compound A-6A (2.23 g, 7.5 mmol) was dissolved in tetrahydrofuran (50 mL) and cooled to -78°C. A 1.6 M hexane solution of n-butyllithium (5.6 mL, 9.0 mmol) was slowly added dropwise, and the temperature was raised to -30°C and stirred for 1 hour. Then, it was cooled again to -78°C, and tributyltin chloride (2.4 mL, 9.0 mmol) was slowly added dropwise, and the mixture was stirred at -78°C for a further 30 minutes. After raising the temperature to room temperature overnight, methanol and water were sequentially added to quench the reaction solution, and it was extracted with ethyl acetate. The resulting ethyl acetate solution containing the target compound was washed with water and saturated brine and dried over magnesium sulfate. After removing the solid by vacuum filtration, the solution was distilled off to obtain compound A-6B as a yellowish-brown liquid. Compound A-6B contained by-products, but it was used in the next step without further purification.

[0162] The entire amount of compound A-6B obtained above, compound A-1D (961 mg, 3.3 mmol), and dichlorobis(triphenylphosphine)palladium(II) (230 mg, 0.33 mmol) were dissolved in dioxane (50 mL) and stirred under reflux conditions for 4 hours. Further addition of dichlorobis(triphenylphosphine)palladium(II) (230 mg, 0.33 mmol) was added and stirred for 3 hours, after which the mixture was cooled to room temperature. The reaction solution was diluted with chloroform, and the insoluble solid was removed by vacuum filtration, after which the filtrate was concentrated. The obtained solid was purified by silica gel column chromatography (eluent: methylene chloride / heptane volume ratio starting at 1 / 6 and then 1 / 5), and 977 mg of compound A-6 was obtained as a blackish-purple solid by reprecipitation in a chloroform / methanol mixed solvent system (yield 41% based on compound A-1D).

[0163] The obtained compound A-6 １ The results of the 1H-NMR analysis are as follows, confirming that the blackish-purple powder obtained above is compound A-6. １ H-NMR (CDCl ３(δ / ppm): 8.14 (s, 2H), 7.86 (s, 2H), 7.50-7.47 (m, sH), 7.34-7.24 (m, 6H), 7.03 (s, 2H), 2.53 (s, 6H), 1.60 (s, 12H) Sublimation purification was performed to further increase the purity. A tantalum boat containing compound A-6 was placed in a glass tube, and an oil diffusion pump was used to extract 4.0 × 10⁻⁶ －３ The compound A-6 was sublimated by heating at 320°C under Pa pressure. The thin-film absorption characteristics of compound A-6 after sublimation purification were evaluated using the method described above, and the results are shown below. Absorption spectrum (thin film): λmax: 592 nm, full width at half maximum: 169 nm.

[0164] (Example 9) Synthesis of Compound A-7

[0165]

[0166] All of the following reactions were carried out under a nitrogen atmosphere.

[0167] Compound A-1C was synthesized using compound A-1B (2.00 g, 9.7 mmol) as a starting material in the same manner as in Example 1, and the entire amount, including the by-product, was used in the following reaction.

[0168] The entire amount of compound A-1C, 1-bromonaphthalene (2.0 mL, 14.5 mmol), and dichlorobis(triphenylphosphine)palladium(II) (370 mg, 0.048 mmol) were dissolved in dioxane (50 mL), and the mixture was stirred under reflux conditions for 1.5 hours. After the reaction solution was cooled to room temperature, the insoluble solid was removed by vacuum filtration. The obtained filtrate was concentrated, methanol was added to precipitate the solid, and it was removed by vacuum filtration. The filtrate was concentrated and purified by silica gel column chromatography (developing solvent: heptane / ethyl acetate = starting from 1 / 0 and progressing to 1 / 10) to obtain 2.21 g of compound A-7A as a yellow viscous solid (68% yield relative to compound A-1B).

[0169] Compound A-7A (2.21 g, 6.6 mmol) was dissolved in tetrahydrofuran (50 mL) and cooled to -78°C. A 1.6 M hexane solution of n-butyllithium (5.0 mL, 8.0 mmol) was slowly added dropwise, and the temperature was raised to -30°C and stirred for 1 hour. Then, it was cooled again to -78°C, and tributyltin chloride (2.2 mL, 8.0 mmol) was slowly added dropwise, and the mixture was stirred at -78°C for a further 30 minutes. After raising the temperature to room temperature overnight, methanol and water were sequentially added to quench the reaction solution, and it was extracted with ethyl acetate. The resulting ethyl acetate solution containing the target compound was washed with water and saturated brine and dried over magnesium sulfate. After removing the solid by vacuum filtration, the solution was distilled off to obtain compound A-7B as a brown liquid. Compound A-7B contains by-products, but it was used in the next step without further purification.

[0170] The entire amount of compound A-7B obtained above, compound A-1D (888 mg, 3.0 mmol), and dichlorobis(triphenylphosphine)palladium(II) (212 mg, 0.30 mmol) were dissolved in dioxane (50 mL) and stirred under reflux conditions for 4.5 hours. Dichlorobis(triphenylphosphine)palladium(II) (106 mg, 0.15 mmol) was added and the mixture was stirred for a further 2.5 hours, and then dichlorobis(triphenylphosphine)palladium(II) (106 mg, 0.15 mmol) was added and the mixture was stirred for 2 hours. The reaction solution was cooled to room temperature, diluted with chloroform, and insoluble solids were removed by vacuum filtration. Then, the mixture was purified by silica gel short-pass purification with chloroform, and the solvent was removed by distillation to obtain the crude product. This compound was then purified by silica gel column chromatography (developing solvent: starting with a volume ratio of 1 / 4 methylene chloride / heptane and finally 1 / 3), and reprecipitation was performed in a chloroform / methanol mixed solvent system to obtain 1.57 g of compound A-7 as a blackish-purple solid (65% yield relative to compound A-1D).

[0171] The obtained compound A-7 １ The results of the 1H-NMR analysis are as follows, confirming that the blackish-purple powder obtained above is compound A-7.１ H-NMR (CDCl ３ (δ / ppm)): 8.41 - 8.38 (m, 2H), 8.28 (s, 2H), 7.93 - 7.85 (m, 6H), 7.65 (d, 2H), 7.57 - 7.50 (m, 6H), 7.21 (s, 2H), 1.65 (s, 12H) In order to further increase the purity, sublimation purification was carried out. The tantalum boat containing Compound A-7 was placed in a glass tube and heated to 350 °C under a pressure of 4.8×10 －３ Pa for sublimation. For Compound A-7 after sublimation purification, the results of evaluating the thin film absorption characteristics by the above method are shown below. Absorption spectrum (thin film): λmax: 593 nm, full width at half maximum: 172 nm.

[0172] (Example 10) Synthesis of Compound A-8

[0173]

[0174] All the following reactions were carried out under a nitrogen atmosphere.

[0175] Compound A-1C was synthesized using Compound A-1B (3.00 g, 14.5 mmol) as a starting material in the same manner as in Example 1 and used in the next reaction in its entirety including by-products.

[0176] The entire amount of the above Compound A-1C, 4-bromoanisole (2.7 mL, 21.8 mmol), tetrakis(triphenylphosphine)palladium(0) (841 mg, 0.73 mmol), 2,6-di-tert-butylpyridine (3.8 mL, 17.5 mmol) were dissolved in toluene (70 mL), and stirred under heating reflux conditions for 4 hours. After the reaction solution was cooled to room temperature, insoluble solids were removed by filtration under reduced pressure. The obtained filtrate was concentrated, methanol was added to precipitate a solid, and the solid was removed by filtration under reduced pressure. The filtrate was concentrated and purified by silica gel column chromatography (developing solvent: starting from heptane / toluene = 1 / 0 and then 1 / 2), and 2.17 g of Compound A-8A was obtained as a yellow viscous solid (yield 48% based on Compound A-1B).

[0177] Compound A-8A (2.27 g, 6.9 mmol) was dissolved in tetrahydrofuran (50 mL) and cooled to -78°C. A 1.6 M hexane solution of n-butyllithium (5.2 mL, 8.3 mmol) was slowly added dropwise, and the temperature was raised to -30°C and stirred for 1 hour. Then, it was cooled again to -78°C, and tributyltin chloride (2.2 mL, 8.3 mmol) was slowly added dropwise, and the mixture was stirred at -78°C for another 30 minutes. After raising the temperature to room temperature overnight, methanol and water were sequentially added to quench the reaction solution, and it was extracted with dichloromethane. The resulting dichloromethane solution containing the target compound was washed with water and saturated brine and dried over magnesium sulfate. After removing the solid by vacuum filtration, the solution was distilled off to obtain compound A-8B as a brown liquid. Compound A-8B contains by-products, but it was used in the next step without further purification.

[0178] The entire amount of compound A-8B obtained above, compound A-1D (972 mg, 3.3 mmol), tetrakistriphenylphosphine palladium (0) (382 mg, 0.33 mmol), and 2,6-di-tert-butylpyridine (1.5 mL, 6.6 mmol) were dissolved in toluene (50 mL) and stirred under reflux conditions for 3 hours. Tetrakistriphenylphosphine palladium (0) (191 mg, 0.17 mmol) was added and stirred for 2 hours, then tetrakistriphenylphosphine palladium (0) (191 mg, 0.17 mmol) was added and stirred for another 2 hours. Finally, tetrakistriphenylphosphine palladium (0) (191 mg, 0.17 mmol) was added and stirred for 3.5 hours, after which it was cooled to room temperature, the reaction solution was diluted with chloroform, and the insoluble solid was removed by vacuum filtration. The solution was concentrated and washed with methanol, and the solid was recovered by vacuum filtration, after which it was purified by silica gel short-pass purification with chloroform. The obtained solid was reprecipitationd from a toluene / heptane mixed solvent system to yield 1.50 g of compound A-8 as a blackish-purple solid (60% yield relative to compound A-1D).

[0179] The obtained compound A-8 １The results of the 1H-NMR analysis are as follows, confirming that the blackish-purple powder obtained above is compound A-8. １ H-NMR (CDCl ３ (δ / ppm): 8.11 (s, 2H), 7.84 (s, 2H), 7.56 (d, 4H), 7.17 (s, 2H), 6.93 (d, 4H), 3.86 (s, 6H), 1.59 (s, 12H) Sublimation purification was performed to further increase the purity. A tantalum boat containing compound A-8 was placed in a glass tube, and an oil diffusion pump was used to extract 2.8 × 10⁻¹⁶ of the compound. －３ The compound A-8 was sublimated by heating at 340°C under Pa pressure. The thin-film absorption characteristics of compound A-8 after sublimation purification were evaluated using the method described above, and the results are shown below. Absorption spectrum (thin film): λmax: 612 nm, full width at half maximum: 190 nm.

[0180] (Comparative Example 1) A photosensor was fabricated and evaluated in the same manner as in Example 1, except that compound B-1 was used instead of compound A-1. The external quantum efficiency at 530 nm for green light was 10.2%, and the external quantum efficiency at 630 nm for red light was 0.2%. It showed sensitivity to green light but not to red light.

[0181]

[0182] (Comparative Example 2) Compound B-2, synthesized using iodohexane instead of iodomethane in Example 1, had high viscosity due to the hexyl group, making sublimation purification and the fabrication of a photosensor impossible.

[0183]

[0184] (Comparative Example 3) Compound A-2 was used instead of compound A-1 as the p-type organic semiconductor, and fullerene (C) was used as the n-type organic semiconductor. ６０ A photosensor was fabricated in the same manner as in Example 1, except that dicyanovinyl compound C-1 was used instead of ). When evaluated using the same method, the external quantum efficiency at 530 nm for green light was 0.7%, and the external quantum efficiency at 630 nm for red light was 0.4%. Unlike Examples 5 and 7, it showed no sensitivity to either green or red light.

Claims

1. An optical sensor material having a structure represented by the following general formula (1). In the general formula (1), R １ ~R ８ are each independently selected from the group consisting of a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, a heteroaryl group, an alkoxy group, a halogen atom, a cyano group, a nitro group, a silyl group, and a boryl group. R ９ ~R １２ are each independently an alkyl group having less than 6 carbon atoms. X is an oxygen atom, a sulfur atom, or a selenium atom. Y １ ~Y ４ are each independently selected from the group consisting of NR １３ , an oxygen atom, and a sulfur atom. R １３ is a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or a heteroaryl group. Z 1 and Z ２ are each independently selected from the group consisting of a carbon atom, a silicon atom, or a germanium atom.

2. R ９ ~R １２ The optical sensor material according to claim 1, wherein each of them is independently a methyl group or an ethyl group.

3. R ９ ~R １２ The optical sensor material according to claim 1, wherein the group is a methyl group.

4. The optical sensor material according to claim 1, wherein X is a sulfur atom.

5. Y １ ~Y ４ The optical sensor material according to claim 1, wherein the atom is a sulfur atom.

6. Z １ and Z ２ The optical sensor material according to claim 1, wherein each of them is independently a carbon atom or a silicon atom.

7. A photosensor that converts light into electric current, wherein a photoelectric conversion layer is present between an anode and a cathode, and the photoelectric conversion layer contains the photosensor material described in any one of claims 1 to 6.

8. The optical sensor according to claim 7, wherein the optical sensor material is an electronic donor material.

9. The optical sensor according to claim 8, wherein the photoelectric conversion layer further contains an electron acceptor material.

10. A display device having the light sensor and organic light-emitting element described in claim 7, and having the function of detecting biological information using the light of the organic light-emitting element.

11. The display device according to claim 10, wherein the biometric information is fingerprint information.

12. The display device according to claim 10, wherein the biological information is blood flow information.

13. A compound having a structure represented by the following general formula (2). In the above general formula (2), R １４ and R １５ Each is independently selected from the group consisting of a hydrogen atom, an alkyl group, and an aryl group. ３ and Z ４ Each of these atoms is independently selected from the group consisting of carbon atoms, silicon atoms, or germanium atoms.

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