Light-absorbing composition, method for producing light-absorbing composition, light-absorbing film, filter, and method for producing filter

Abstract

This light-absorbing composition contains an ultraviolet-absorbing compound having a hydroxyl group and a carbonyl group in the molecule, a metal component, polyvinyl butyral, and an isocyanate. At least a portion of the metal component is bonded to the organic oxygen group.

Description

Technical Field

[0001] The present invention relates to a light-absorbing composition, a light-absorbing film and an optical filter. Background Art

[0002] In an imaging device using a solid-state imaging element such as a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor), various filters are arranged in front of the solid-state imaging element in order to obtain an image with good color reproducibility. Solid-state imaging elements generally have a spectral sensitivity in a wavelength range wider than the visual sensitivity of humans corresponding to the visible light region. Therefore, in order to make the spectral sensitivity of the solid-state imaging element in the imaging device close to the visual sensitivity of humans, it is known that there is a technology for arranging a filter in front of the solid-state imaging element to shield a portion of infrared or ultraviolet light.

[0003] In the past, filters that shield infrared or ultraviolet rays by using light reflection based on dielectric multilayer films were common as such filters. On the other hand, in recent years, filters having films containing light absorbers have attracted attention. The transmittance characteristics of filters having films containing light absorbers are not easily affected by the angle of incidence, so in an imaging device, even when light is incident on the filter at an angle, a good image with little change in color tone can be obtained. In addition, in a light absorption type filter that does not use a light reflection film, the generation of ghosting or light spots caused by multiple reflections based on the light reflection film can be suppressed, so it is easy to obtain a good image in backlit conditions or night scene shooting. In addition, filters having films containing light absorbers are also advantageous from the perspective of miniaturization and thinning of imaging devices.

[0004] As such a light absorber, a light absorber composed of phosphonic acid and copper ions is known. For example, Patent Document 1 describes an optical filter having a light absorbing layer containing a light absorber composed of phosphonic acid having a phenyl group or a halogenated phenyl group (phenyl-based phosphonic acid) and copper ions.

[0005] In addition, Patent Document 2 describes an optical filter having a UV-IR absorbing layer capable of absorbing infrared and ultraviolet rays. The UV-IR absorbing layer contains a UV-IR absorber formed of phosphonic acid and copper ions. In order to make the optical filter satisfy the prescribed optical properties, the UV-IR absorbing composition contains, for example, phenyl-based phosphonic acid and phosphonic acid having an alkyl group or a halogenated alkyl group (alkyl-based phosphonic acid).

[0006] In addition, an ophthalmic instrument including a violet light vertical cut filter is described in Patent Document 3. The violet light vertical cut filter sharply absorbs light having a wavelength in the range of approximately 400 nm to 450 nm.

[0007] Prior art literature

[0008] Patent Literature

[0009] Patent Document 1: International Publication No. 2018 / 088561

[0010] Patent Document 2: Japanese Patent No. 6232161

[0011] Patent Document 3: Japanese Patent Application No. 2007-535708 Summary of the invention

[0012] Problems to be solved by the invention

[0013] The technologies described in Patent Documents 1 and 2 have room for further study from the perspective of shielding properties of light in the short wavelength region below 410 nm. In addition, in the violet light vertical cutoff filter described in Patent Document 3, it is believed that the transmittance of visible light above 450 nm is low. In addition, in the technologies described in Patent Documents 1 to 3, there is room for further study on the cleaning of the filter or the durability during the manufacturing process of the filter.

[0014] Therefore, the present invention provides a light-absorbing composition, a light-absorbing film, and an optical filter, which are advantageous from the perspective of reproducing human visual sensitivity, particularly absorption characteristics of light in a short wavelength region, and are advantageous from the perspective of durability during cleaning or manufacturing of the optical filter.

[0015] Means for solving problems

[0016] The present invention provides a light absorbing composition comprising:

[0017] UV absorbing compounds having hydroxyl and carbonyl groups in the molecule;

[0018] metal composition;

[0019] Polyvinyl butyral; and

[0020] Isocyanates,

[0021] At least a part of the metal component is bonded to the organic oxygen group.

[0022] The present invention also provides a method for producing the light-absorbing composition, comprising adding and mixing an ultraviolet-absorbing compound having a hydroxyl group and a carbonyl group in its molecule, a compound containing a metal component, polyvinyl butyral, and an isocyanate in an organic solvent.

[0023] In addition, the present invention provides a light-absorbing film comprising:

[0024] UV absorbing compounds having hydroxyl and carbonyl groups in the molecule;

[0025] Metal content; and

[0026] Resins having urethane bonds,

[0027] At least a part of the metal component is bonded to the organic oxygen group.

[0028] Furthermore, the present invention provides an optical filter comprising the above-mentioned light absorbing film.

[0029] The present invention also provides a method for producing an optical filter including the above-mentioned light-absorbing film, wherein the method includes the step of any one of the following (i) or (ii).

[0030] (i) The light absorbing film is formed on an imaging element or an optical component.

[0031] (ii) forming the light absorbing film on a substrate, and peeling the light absorbing film from the substrate.

[0032] Effects of the Invention

[0033] The light-absorbing composition is advantageous from the perspective of reproducing the visual sensitivity of human beings, especially the absorption characteristics of light in the short wavelength region, and is also advantageous from the perspective of durability during cleaning or manufacturing of the optical filter. In addition, the light-absorbing film and the optical filter are advantageous from the perspective of reproducing the visual sensitivity of human beings, especially the absorption characteristics of light in the short wavelength region. Furthermore, the light-absorbing film and the optical filter are not easily scratched even when the surface is cleaned or wiped, which is also advantageous from the perspective of durability. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a cross-sectional view showing an example of the light-absorbing film of the present invention.

[0035] Figure 2A This is a cross-sectional view showing an example of the optical filter of the present invention.

[0036] Figure 2B This is a cross-sectional view showing an example of the optical filter of the present invention.

[0037] Figure 3 is the transmission spectrum of the filter of Example 1.

[0038] Figure 4 is the transmission spectrum of the filter of Example 5.

[0039] Figure 5 is the transmission spectrum of the filter of Example 7.

[0040] Figure 6 is the transmission spectrum of the filter of Example 9.

[0041] Figure 7 is the transmission spectrum of the filter of Example 11.

[0042] Figure 8 : is the reflection spectrum of the filter of Example 1.

[0043] Fig. 9 This is the reflection spectrum of the filter of Example 5.

[0044] Fig.10 It is the reflection spectrum of the filter of Example 7.

[0045] Fig.11 It is the reflection spectrum of the filter of Example 9.

[0046] Fig.12 is the reflection spectrum of the filter of Example 11.

[0047] Fig.13 is the transmission spectrum of the transparent glass substrate. DETAILED DESCRIPTION

[0048] In the optical filter used in the imaging device using the solid-state imaging element, if it can effectively absorb the light in the short wavelength region below 410nm, the value of the filter can be further improved from the perspective of reproducing the visual sensitivity of human beings. According to the optical filter described in Patent Document 1, the wavelength at which the spectral transmittance becomes 50% in the wavelength range of 350nm to 450nm is less than 400nm. According to the optical filter described in Patent Document 2, the wavelength at which the spectral transmittance becomes 50% in the wavelength range of 350nm to 450nm is approximately 390nm to 415nm. Based on these facts, the optical filters described in Patent Documents 1 and 2 are difficult to be said to be advantageous from the perspective of effectively absorbing the light in the short wavelength region below 410nm. The purple light vertical cutoff filter described in Patent Document 3 has the possibility of effectively absorbing the light in the short wavelength region below 410nm, but it is considered that the transmittance of the filter to the visible light above 450nm is low.

[0049] Therefore, the present inventors have conducted intensive studies to develop a light-absorbing composition that is advantageous from the perspective of reproducing human visual sensitivity, particularly effective absorption of light in a short wavelength region of 410 nm or less. As a result of repeated trial and error, the present inventors have newly discovered that a light-absorbing composition containing a predetermined ultraviolet absorbing compound and a metal component is advantageous from the perspective of effective absorption of light in a short wavelength region.

[0050] In addition, the inventors have repeatedly conducted further studies on whether it is possible to impart advantageous properties to the light-absorbing composition containing the ultraviolet absorbing compound and the metal component from the aspect of durability during cleaning or manufacturing of the optical filter. For example, the optical filter is sometimes cleaned by wiping with a rag or cloth or microfiber containing an organic solvent such as alcohol and acetone. In addition, during the manufacturing process of the optical filter, the portion containing the light-absorbing composition or the cured product of the light-absorbing composition has the possibility of contacting other components. Under such circumstances, it is important for the light-absorbing composition containing the ultraviolet absorbing compound and the metal component to have advantageous properties from the aspect of durability or solvent resistance related to surface mechanical strength during cleaning or manufacturing of the optical filter in order to increase the added value of the light-absorbing composition, the light-absorbing film or the optical filter. For example, it is important for the light-absorbing composition to have advantageous properties from the aspect of scratch resistance and solvent resistance during cleaning or manufacturing of the optical filter.

[0051] On the other hand, it is not easy to achieve both "properties that are advantageous from the perspective of durability during cleaning or manufacturing of the filter" and "reproduction of human visual sensitivity, especially effective absorption of light in the short wavelength region of 410 nm or less". The reason is that in the selection of components added to the light-absorbing composition in order to provide durability during cleaning or manufacturing of the filter, it is necessary to carefully study whether the effective absorption of light in the short wavelength region of 410 nm or less will be impaired due to the interaction between the components and the ultraviolet absorbing compound and the like. The present inventors have repeatedly conducted a large number of trials and errors from such a perspective. As a result, the present inventors have newly identified an additive component that can provide properties that are advantageous from the perspective of durability during cleaning or manufacturing of the filter without impairing the effective absorption of light in the short wavelength region of 410 nm or less in the above-mentioned light-absorbing composition containing the ultraviolet absorbing compound and the metal component, thereby completing the present invention.

[0052] The following is a description of an embodiment of the present invention. It should be noted that the following description is for illustration of the present invention, and the present invention is not limited to the following embodiment.

[0053] The light-absorbing composition of the present invention contains an ultraviolet-absorbing compound having a hydroxyl group and a carbonyl group in the molecule, a metal component, polyvinyl butyral (PVB), and an isocyanate. The isocyanate in this specification is a compound containing -N=C=O (isocyanate group) in the molecule. In addition, at least a portion of the metal component is bonded to an organic oxygen group. Typically, at least a portion of the metal component is bonded to an oxygen atom in the organic oxygen group. As a result, a light-absorbing film or filter made using the light-absorbing composition can easily and effectively absorb light in a short wavelength region below 410 nm. In addition, the light-absorbing film or filter can exhibit high transmittance in the visible light region. Therefore, the light-absorbing composition is advantageous from the perspective of reproducing human visual sensitivity.

[0054] As conditions favorable to ultraviolet absorbing compounds, there are: appropriate light absorption range and transmission range; photochemical stability; photosensitization is reduced to a level that has no effect within the use range; thermochemical stability and other conditions. From this aspect, as a mechanism of light absorption by ultraviolet absorbing compounds, it is considered to utilize the hydrogen transfer reaction of the hydroxyl group in the molecule caused by light excitation (intramolecular hydrogen abstraction reaction). As ultraviolet absorbing compounds that exert such a mechanism, for example, compounds such as hydroxybenzophenone, salicylic acid, hydroxyphenylbenzotriazole, hydroxyphenyltriazine and substituted acrylonitrile can be cited. In hydroxybenzophenone and salicylic acid, the reaction related to the hydrogen transfer between the hydroxyl group and the carbonyl group contained in the molecule involves the light absorption of ultraviolet rays, etc. On the other hand, in hydroxyphenylbenzotriazole, hydroxyphenyltriazine and substituted acrylonitrile, the reaction related to the hydrogen transfer between the hydroxyl group and the nitrogen atom contained in the molecule involves the light absorption of ultraviolet rays, etc. These ultraviolet absorbing compounds have hydroxyl groups with non-shared electron pairs in their molecules, so it is speculated that they produce interactions such as partial complexation with coexisting metal components or hydrogen donors. In a system such as a light-absorbing composition and a cured product thereof containing a UV-absorbing compound, a comparison is made between the case where a UV-absorbing compound having a hydroxyl group exists alone and the case where a metal component or a hydrogen donor and a UV-absorbing compound having a hydroxyl group coexist. According to the comparison, their optical properties such as light absorption spectra and their light transmission spectra differ, supporting the above speculation. In particular, it is known that in a light-absorbing film or an optical filter having a light-absorbing film obtained by curing a light-absorbing composition containing a UV-absorbing compound having a hydroxyl group and a carbonyl group in the molecule and a metal component, a part of the light absorption band within a wavelength of 300 to 500 nm shifts to the long wavelength side. Therefore, such a light-absorbing film has a characteristic that is advantageous for effectively and appropriately absorbing light with a wavelength of 410 nm or less. It should be noted that if the light absorption band shifts to the long wavelength side, for example, the phenomenon that the absorption maximum wavelength shifts to the long wavelength side within the wavelength range of 300 nm to 500 nm of the transmission spectrum, or the phenomenon that the wavelength (UV cutoff wavelength) at which the transmittance becomes 50% shifts to the long wavelength side may become obvious. Thus, according to the light-absorbing composition of the present invention, the light-absorbing film as a cured product thereof, and the optical filter having the light-absorbing film, the absorption characteristics originally possessed by the ultraviolet absorbing compound are adjusted so as to effectively absorb light in the short wavelength region. As a result, when used together with a solid-state imaging element or the like, the spectral transmittance of such a light-absorbing film or optical filter is likely to become more appropriate.

[0055] As described above, the light absorbing composition contains PVB and isocyanate. As a result, the light absorbing composition is likely to have advantageous properties from the perspective of durability during cleaning or manufacturing of the optical filter. In particular, it is advantageous for the light absorbing composition to contain PVB and isocyanate from the perspective of improving scratch resistance and solvent resistance during cleaning or manufacturing of the optical filter. Furthermore, even if the light absorbing composition contains PVB and isocyanate, it does not prevent the absorption characteristics inherent in the ultraviolet absorbing compound from being adjusted so that light in the short wavelength region can be effectively absorbed by the above-mentioned mechanism of action.

[0056] PVB is, for example, likely to have high transparency and high compatibility with organic solvents. In addition, PVB has high weather resistance and high light resistance. When a light-absorbing composition contains PVB, a light-absorbing film and an optical filter obtained from the light-absorbing composition are likely to exhibit high weather resistance and light resistance. In addition, PVB can exhibit advantageous properties as a binder for functional components such as the above-mentioned ultraviolet absorbing compound.

[0057] PVB exhibits good adhesion to the surfaces of lenses or other optical elements and substrates such as transparent dielectric substrates. Therefore, the light-absorbing composition can also have advantageous properties in the production of composite optical elements or optical parts composed of two or more components or parts.

[0058] PVB is represented by the following structural formula, for example: In the following structural formula, k is the molar fraction [%] of the structural unit having a vinyl butyral group, m is the molar fraction [%] of the structural unit derived from vinyl alcohol and having a hydroxyl group, and n is the molar fraction [%] of the structural unit derived from vinyl acetate.

[0059] [Chemistry 1]

[0060]

[0061] PVB is obtained by reacting butyraldehyde with polyvinyl alcohol (PVA). Since all vinyl groups of PVA cannot be esterified, groups containing hydroxyl groups partially exist in PVB.

[0062] The number average molecular weight of PVB contained in the light absorbing composition is not limited to a specific value. The number average molecular weight is, for example, 12.0×10 4 As a result, the film formation of the light-absorbing composition is facilitated, and the haze of the light-absorbing film and the optical filter obtained from the light-absorbing composition is easily reduced. The number average molecular weight of PVB is, for example, 1.0×10 4As a result, the shrinkage of the light-absorbing composition during curing is not likely to increase, and the haze of the light-absorbing film and filter obtained from the light-absorbing composition is easily reduced. The number average molecular weight of PVB can be 1.2×10 4 Above, it can also be 1.5×10 4 The number average molecular weight of PVB can be 11.5×10 4 Below, it can also be 11.0×10 4 The number average molecular weight of PVB can be measured, for example, in accordance with Japanese Industrial Standard (JIS) K7252-1:2016.

[0063] The butyralization degree of PVB is not limited to a specific value. The butyralization degree is, for example, 60 mol% or more. Thus, it is easy to adjust the hydrophobicity and toughness of the surface of the light-absorbing film or filter obtained from the light-absorbing composition to the desired level. The butyralization degree is preferably 65 mol% or more. The butyralization degree is, for example, 90 mol% or less. Thus, it is easy for a desired amount of hydroxyl groups to exist in PVB. The butyralization degree is preferably 80 mol% or less. The butyralization degree of PVB is, for example, a value expressed as a percentage by dividing the amount of ethylene groups bonded to the butyral group by the total amount of ethylene groups in the main chain. The butyralization degree can be calculated, for example, as follows: the acetylation degree and the hydroxyl content are measured according to the method based on JIS K 6728 (Test method for polyvinyl butyral), the mole fraction is calculated based on the obtained measurement results, and then the acetylation degree and the hydroxyl content are subtracted from 100 mol%, thereby calculating the butyralization degree.

[0064] The content of hydroxyl groups in PVB is not limited to a specific value. This content is, for example, 10 mol% or more. Thus, as described below, hydroxyl groups in an amount sufficient for reaction with isocyanate in the curing of the light-absorbing composition are easily present in PVB. The content of hydroxyl groups in PVB is preferably 20 mol% or more. The content of hydroxyl groups in PVB is, for example, 50 mol% or less. Thus, it is easy to include a desired amount of butyral groups in PVB from the perspective of toughness. The content of hydroxyl groups in PVB is preferably 40 mol% or less. The content of hydroxyl groups can be calculated, for example, according to the method based on JIS K6728 (Test method for polyvinyl butyral).

[0065] Examples of PVB are S-LECKS-1, S-LECKS-10, S-LECBX-L, S-LECBX-1, S-LECBL-S, and S-LECBL-1 manufactured by Sekisui Chemical Co., Ltd. S-LEC is a registered trademark. Another example of PVB is Mowital B20H, Mowital B30T, Mowital B30H, and Mowital B45H manufactured by KURARAY. Mowital is a registered trademark. In the light absorbing composition, one or more PVBs are selected from these PVBs or used in combination.

[0066] The isocyanate contained in the light absorbing composition has, for example, two or more isocyanate groups in the molecule, each of which is bonded to a carbon atom. As described above, the PVB molecule contains a hydroxyl group, and PVB can undergo a cross-linking reaction with the isocyanate. Through the cross-linking reaction, the hydroxyl group of the PVB is consumed, and a three-dimensional network structure can be formed. Specifically, as shown in the following reaction formula, through the isocyanate group R 1 -N=C=O and the hydroxyl R contained in PVB 2 -OH to produce a carbamate bond R 1 -NH-COO-R 2 As a result, the surface hardness of the cured product of the light absorbing composition is increased, and advantageous mechanical properties and solvent resistance can be achieved from the perspective of durability during cleaning or manufacturing of the optical filter.

[0067] [Chemistry 2]

[0068]

[0069] The presence or absence of a carbamate bond can be determined by, for example, obtaining an infrared spectrum of the sample using a method such as Fourier transform infrared spectroscopy (FT-IR) and analyzing the presence or absence and intensity of a peak characteristic of a carbamate bond in the infrared spectrum. The presence or absence of a peak characteristic of a carbamate bond can be determined. The characteristic peak is, for example, 3450 cm -1 ~3000cm -1 Within the range (e.g. 3290cm -1 ) derived from the stretching vibration of NH, 1735 cm -1 ~1691cm -1 Within the range (e.g. 1725cm -1 and 1705cm -1 ) derived from the stretching vibration of C=O (amide I), and 1530 cm -1 There are also peaks nearby originating from the angular vibration of NH (amide II), etc.

[0070] The isocyanate contained in the light absorbing composition is not limited to a specific isocyanate. Isocyanate is a compound having an isocyanate group in the molecule. Examples of isocyanates are toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), hexamethylene diisocyanate (HDI), phenylene diisocyanate, dinaphthalene diisocyanate, isophorone diisocyanate and xylylene diisocyanate. Another example of isocyanate is trimethylene diisocyanate, tetramethylene diisocyanate, pentamethylene diisocyanate and trimethylhexamethylene diisocyanate. Isocyanate can also be an alicyclic polyisocyanate. Examples of alicyclic polyisocyanates are isophorone diisocyanate, dicyclohexylmethane diisocyanate, 1,3-bis(isocyanate methyl)cyclohexane and bis(isocyanatomethyl)norbornane. Isocyanate can also be an aromatic aliphatic polyisocyanate. Examples of aromatic aliphatic polyisocyanates are xylylene diisocyanate, tetramethylxylylene diisocyanate, and ω,ω′-diisocyanato-1,4-diethylbenzene.

[0071] As described above, in the light absorbing composition, at least a part of the metal component is bonded to an organic radical, including a compound containing a metal component bonded to an organic radical. Here, the compound containing a metal component bonded to an organic radical is generally (R k -O) n -M. M represents a metal component such as a metal atom or a metal ion. (R k -O) n -group represents n organic radicals (or collectively referred to as organic radicals, the same below), R k represents an organic group containing at least carbon atoms (C) and hydrogen atoms (H), and n represents the number of bonds or coordinations with the metal component M. One or more organic oxygen groups can be bonded or coordinated with the metal component M. k -O)- may contain two or more O (oxygen), and the organic radical may be bonded or coordinated to the metal component M via these two or more O (oxygen). k In each organic radical (R k -O)- may be the same or different, and two or more organic oxy groups may be bonded without the metal component M. The organic oxy group is not particularly limited as long as it satisfies the above conditions, and examples thereof include methoxy, ethoxy, propoxy, phenoxy, alkoxy such as alkylphenoxy, and vinyl. In the organic oxy group, the organic group R kIt may include partial structures (groups) of acyl, acetyl, keto, vinyl, propionyl, acryloyl, acetoxy, acryloyl, ethyl acetate, ethyl acetoacetate, acetylacetonato and other esters, ethers, etc. In addition, it may also be an organic oxygen group containing one or more groups selected from them. The metal component M may include, for example, at least one of the groups consisting of metal atoms or ions such as Li, Na, Mg, Ca, Sr, Ba, Ge, Sn, Pb, Al, Ga, In, Tl, Zn, Cd, Cu, Ag, Au, Ni, Pd, Pt, Co, Rh, Ir, Fe, Mn, Cr, Mo, W, V, Nb, Ta, Ti and Zr.

[0072] The configuration of the hydroxyl group and the carbonyl group in the ultraviolet absorbing compound is not limited to a specific configuration. In the ultraviolet absorbing compound, the hydroxyl group and the carbonyl group are preferably configured with 1 to 3 atoms separated. It can be considered that hydrogen transfer is easily generated between the hydroxyl group and the carbonyl group in the ultraviolet absorbing compound. Therefore, it is easy to effectively produce the phenomenon that the light absorption band within the wavelength of 300 to 500nm shifts to the long wavelength side. As a result, the light absorbing film obtained by curing the light absorbing composition is easy to more reliably and effectively absorb light with a wavelength of less than 410nm.

[0073] The ultraviolet absorbing compound is not limited to a specific compound as long as it has a hydroxyl group and a carbonyl group in its molecule. The ultraviolet absorbing compound is preferably a compound that is not easily aggregated even when mixed with a metal component.

[0074] The ultraviolet absorbing compound preferably includes a benzophenone compound represented by the following formula (A1): In this case, a light absorbing film or optical filter produced using the light absorbing composition can more reliably and effectively absorb light in a short wavelength region of 410 nm or less.

[0075] [Chemistry 3]

[0076]

[0077] In formula (A1), R 11 , R 12 , R 21 and R 22 At least one of them is a hydroxyl group. In formula (A1), R 11 , R 12 , R 21 or R 22 In the case of a functional group other than a hydroxyl group, there may be two or more R 11 , 2 or more R 12 , 2 or more R 21 Or 2 or more R 22 , R 11, R 12 , R 21 and R 22 At least one of may not exist.

[0078] R 11 , R 12 , R 21 or R 22 In the case of a functional group other than a hydroxyl group, the functional group is, for example, a carboxyl group, an aldehyde group, a halogen atom, an alkyl group having 1 to 12 carbon atoms, an alkyl group having 1 to 12 carbon atoms in which one or more hydrogen atoms are substituted by a halogen atom, an alkoxy group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms in which one or more hydrogen atoms are substituted by a halogen atom.

[0079] The ultraviolet absorbing compound more preferably includes a benzophenone compound represented by the following formula (A2). In this case, a light absorbing film or optical filter produced using the light absorbing composition can more reliably and effectively absorb light in a short wavelength region of 410 nm or less.

[0080] [Chemistry 4]

[0081]

[0082] In formula (A2), R 31 is a hydrogen atom, a hydroxyl group, a carboxyl group, an aldehyde group, a halogen atom, a group having a halogen atom, an alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. 41 and R 42 It may be a hydroxyl group, a carboxyl group, an aldehyde group, a group having a halogen atom, an alkyl group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. 41 and R 42 In formula (A2), there may be two or more R 41 , there can also be more than 2 R 42 The group having a halogen atom may be a halogenated alkyl group in which at least one hydrogen atom in an alkyl group is replaced by a halogen atom. The group having a halogen atom may be a halogenated aryl group in which at least one hydrogen atom in an aryl group is replaced by a halogen atom. The group having a halogen atom may be a halogenated alkoxy group in which at least one hydrogen atom in an alkoxy group is replaced by a halogen atom.

[0083] The benzophenone compound represented by formula (A1) or formula (A2) is not limited to a specific compound. The benzophenone compound is, for example, at least one selected from the group consisting of 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2,2',4,4'-tetrahydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxy-4'-chlorobenzophenone, 2-hydroxy-4-n-octyloxybenzophenone, 2-hydroxy-4-dodecyloxybenzophenone, 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxy-2'-carboxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, 2,2'-dihydroxy-4-n-octyloxybenzophenone, 2-hydroxy-5-chlorobenzophenone and 2,4-dibenzoylresorcinol.

[0084] The ultraviolet absorbing compound may include a salicylic acid compound represented by the following formula (B): In this case, a light absorbing film or optical filter produced using the light absorbing composition can more reliably and effectively absorb light in a short wavelength region around 410 nm.

[0085] [Chemistry 5]

[0086]

[0087] In formula (B), R 51 It may be a hydroxyl group, a carboxyl group, a group containing a halogen atom, an alkyl group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. 51 , R may not exist 51 In formula (B), R 52 The group having a halogen atom may be a halogenated aryl group in which at least one hydrogen atom in an alkyl group is replaced by a halogen atom. The group having a halogen atom may be a halogenated alkyl group in which at least one hydrogen atom in an aryl group is replaced by a halogen atom. The group having a halogen atom may be a halogenated aryl group in which at least one hydrogen atom in an aryl group is replaced by a halogen atom. The group having a halogen atom may be a halogenated alkoxy group in which at least one hydrogen atom in an alkoxy group is replaced by a halogen atom.

[0088] The salicylic acid compound represented by formula (B) is not limited to a specific compound. For example, the salicylic acid compound represented by formula (B) includes at least one selected from the group consisting of phenyl salicylate, 4-butylphenyl salicylate, and octylphenyl salicylate.

[0089] The metal component is not limited to a specific metal component. The metal component is typically a component that does not aggregate in the light-absorbing composition and the light-absorbing film produced using the light-absorbing composition and is thermally and chemically stable. In addition, the metal component is typically a component that can interact with the above-mentioned ultraviolet absorbing compound.

[0090] The metal component includes, for example, at least one selected from the group consisting of Li, Na, Mg, Ca, Sr, Ba, Ge, Sn, Pb, Al, Ga, In, Tl, Zn, Cd, Cu, Ag, Au, Ni, Pd, Pt, Co, Rh, Ir, Fe, Mn, Cr, Mo, W, V, Nb, Ta, Ti and Zr. In this case, the metal component easily interacts with the above-mentioned ultraviolet absorbing compound.

[0091] Content C of the metal component in the light absorbing composition M It is not limited to a specific value. Content C M The content of C is, for example, 0.005% to 2% by mass. As a result, a light-absorbing film or optical filter produced using the light-absorbing composition can more reliably and effectively absorb light in a short wavelength region of 410 nm or less. M It is preferably 0.01% to 1%, more preferably 0.01% to 0.5%, and even more preferably 0.01% to 0.3%.

[0092] Content C of the ultraviolet absorbing compound in the light absorbing composition UV It is not limited to a specific value. Content C UV The content of C is, for example, 0.1% to 20% by mass. As a result, a light-absorbing film or optical filter produced using the light-absorbing composition can more reliably and effectively absorb light in a short wavelength region of 410 nm or less. UV It is preferably 0.1% to 15%, more preferably 0.2% to 10%, further preferably 0.5% to 10%, and particularly preferably 1% to 10%.

[0093] The ratio R of the content of the ultraviolet absorbing compound to the content of the metal component in the light absorbing composition UV / M It is not limited to a specific value. UV / M The mass standard is, for example, 5 to 300. As a result, a light-absorbing film or optical filter produced using the light-absorbing composition can more reliably and effectively absorb light in a short wavelength region of 410 nm or less. UV / M It is preferably 10 to 300, more preferably 20 to 300, and even more preferably 30 to 280.

[0094] The ratio of the mass of isocyanate to the mass of PVB in the light absorbing composition is I / PIt is not limited to a specific value. I / P For example, it is 0.05 to 3.0. Thus, the surface hardness of the cured product of the light absorbing composition is likely to be higher due to the crosslinking reaction between PVB and isocyanate. I / P It is preferably 0.05 to 3.0, more preferably 0.1 to 0.3, and still more preferably 0.2 to 3.0.

[0095] The ratio R of the mass of the isocyanate to the mass of the ultraviolet absorbing compound in the light absorbing composition is I / UV It is not limited to a specific value. I / UV For example, it is 0.1 to 3.0. As a result, the surface hardness of the cured product of the light-absorbing composition is likely to be higher, and it is easier to achieve mechanical properties and solvent resistance that are advantageous from the perspective of durability during cleaning or manufacturing of the optical filter. I / UV It is preferably 0.2 to 3.0, more preferably 0.25 to 3.0.

[0096] The method for producing the light absorbing composition is not limited to a specific method. The light absorbing composition can be produced, for example, by a method comprising adding and mixing an ultraviolet absorbing compound having a hydroxyl group and a carbonyl group in the molecule, a compound containing a metal component, polyvinyl butyral, and isocyanate in an organic solvent.

[0097] Use of light absorbing compositions can provide, for example, Figure 1 The light absorbing film 10 shown. The light absorbing film 10 is obtained, for example, by curing a light absorbing composition. The light absorbing film 10 contains an ultraviolet absorbing compound having a hydroxyl group and a carbonyl group in the molecule, a metal component, and a resin having a urethane bond. In the light absorbing film 10, at least a portion of the metal component is bonded to an organic oxygen group. At least a portion of the metal component is bonded to an oxygen atom in the organic oxygen group. As a result, the light absorbing film 10 can easily and effectively absorb light in a short wavelength region of 410 nm or less. In addition, by making the light absorbing film 10 contain a resin having a urethane bond, the light absorbing film 10 can easily have advantageous properties from the perspective of improving durability or solvent resistance during cleaning of the filter.

[0098] As described above, in the light absorbing film 10, at least a part of the metal component is bonded to the organic oxygen group, and the compound containing the metal component bonded to the organic oxygen group is included. Here, the compound containing the metal component bonded to the organic oxygen group is generally (R k -O) n -M. M represents a metal component such as a metal atom or a metal ion. (R k -O) n -group represents n organic radicals (or collectively referred to as organic radicals, the same below), R krepresents an organic group containing at least carbon atoms (C) and hydrogen atoms (H), and n represents the number of bonds or coordinations with the metal component M. One or more organic oxygen groups can be bonded or coordinated with the metal component M. k -O)- may contain two or more O (oxygen), and the organic radical may be bonded or coordinated to the metal component M via these two or more O (oxygen). k In each organic radical (R k -O)- may be the same or different, and two or more organic oxy groups may be bonded without the metal component M. The organic oxy group is not particularly limited as long as it satisfies the above conditions, and examples thereof include methoxy, ethoxy, propoxy, phenoxy, alkoxy such as alkylphenoxy, and vinyl. In the organic oxy group, the organic group R k It may include partial structures (groups) of acyl, acetyl, keto, vinyl, propionyl, acryloyl, acetoxy, acryloyl, ethyl acetate, ethyl acetoacetate, acetylacetonato and other esters, ethers, etc. In addition, it may also be an organic oxygen group containing one or more groups selected from them. The metal component M may include, for example, at least one of the groups consisting of metal atoms or ions such as Li, Na, Mg, Ca, Sr, Ba, Ge, Sn, Pb, Al, Ga, In, Tl, Zn, Cd, Cu, Ag, Au, Ni, Pd, Pt, Co, Rh, Ir, Fe, Mn, Cr, Mo, W, V, Nb, Ta, Ti and Zr.

[0099] In the ultraviolet absorbing compound of the light absorbing film 10, the hydroxyl group and the carbonyl group are preferably arranged with 1 to 3 atoms interposed therebetween. This makes it easy to improve the ability of the light absorbing film 10 to absorb light in the wavelength region of 410 nm or less.

[0100] The ultraviolet absorbing compound in the light absorbing film 10 includes, for example, a benzophenone compound represented by the above formula (A1). This makes it easy to improve the ability of the light absorbing film 10 to absorb light in the wavelength region of 410 nm or less.

[0101] The ultraviolet absorbing compound in the light absorbing film 10 preferably includes a benzophenone compound represented by the above formula (A2). This makes it easy to improve the ability of the light absorbing film 10 to absorb light in the wavelength region of 410 nm or less.

[0102] The ultraviolet absorbing compound in the light absorbing film 10 may include, for example, a salicylic acid compound represented by the above formula (B). In this case, the ability of the light absorbing film 10 to absorb light in a wavelength region of 410 nm or less can be easily improved.

[0103] The metal component in the light absorbing film 10 includes, for example, at least one selected from the group consisting of Li, Na, Mg, Ca, Sr, Ba, Ge, Sn, Pb, Al, Ga, In, Tl, Zn, Cd, Cu, Ag, Au, Ni, Pd, Pt, Co, Rh, Ir, Fe, Mn, Cr, Mo, W, V, Nb, Ta, Ti and Zr.

[0104] In the light absorbing film 10, the ratio of the content of the ultraviolet absorbing compound to the content of the metal component is UV / M It is not limited to a specific value. UV / M The mass standard is, for example, 5 to 300. As a result, a light-absorbing film or optical filter produced using the light-absorbing composition can more reliably and effectively absorb light in a short wavelength region of 410 nm or less. UV / M It is preferably 10 to 300, more preferably 20 to 300, and even more preferably 30 to 280.

[0105] The transmittance T of the light absorbing film 10 400 For example, it is 5% or less. This is advantageous from the perspective of reproducing human visual sensitivity. 400 It is the transmittance at a wavelength of 400nm in the transmission spectrum with an incident angle of 0°. Transmittance T 400 It is preferably 4.5% or less, and more preferably 4% or less.

[0106] The content of the ultraviolet absorbing compound in the light absorbing film 10 is not limited to a specific value, but is, for example, 0.1% to 90% by mass, preferably 0.5% to 80% by mass, and more preferably 2% to 70% by mass.

[0107] The content of the metal component in the light absorbing film 10 is not limited to a specific value, but is, for example, 0.005% to 5% by mass, preferably 0.01% to 4%, and more preferably 0.03% to 3% by mass.

[0108] In the light absorbing film 10, the ratio of the mass of isocyanate to the mass of PVB is I / P It is not limited to a specific value. I / P For example, it is 0.05 to 3.0, preferably 0.05 to 2.5, more preferably 0.05 to 2.0, and further preferably 1.0 to 2.0.

[0109] In the light absorbing film 10, the ratio of the mass of the isocyanate to the mass of the ultraviolet absorbing compound is I / UV It is not limited to a specific value. I / UV For example, it is 0.1 to 3.0, preferably 0.2 to 2.8, and more preferably 0.2 to 2.5.

[0110] The thickness of the light absorbing film 10 is not limited to a specific value, and the thickness of the light absorbing film 10 is, for example, 0.5 μm to 500 μm, 1 μm to 100 μm, or 1 μm to 50 μm.

[0111] In the manufacture of the light absorbing film 10, the method of curing the light absorbing composition is not limited to a specific method. For example, the curing conditions of the light absorbing composition are adjusted in such a way that the PVB contained in the light absorbing composition and the isocyanate undergo a cross-linking reaction. Thus, the light absorbing film 10 contains a resin having a urethane bond. For example, the light absorbing composition can be cured by heating it at a predetermined temperature. In this case, the predetermined temperature is, for example, 80°C or more, preferably 100°C or more, more preferably 120°C or more, and further preferably 140 to 180°C. Thus, the degradation of the ultraviolet absorbing compound can be prevented, and the light absorbing film 10 is likely to have advantageous properties from the aspect of durability during cleaning of the optical filter.

[0112] like Figure 1 and Figure 2A As shown, for example, it is possible to provide optical filters 1a and 1b each having a light absorbing film 10. The optical filters 1a and 1b can easily and effectively absorb light in a short wavelength region of 410 nm or less.

[0113] In the transmission spectra of filters 1a and 1b at an incident angle of 0 degrees, the transmittance T at a wavelength of 410 nm is 410 For example, it is 20% or less, preferably 15% or less, and more preferably 10% or less.

[0114] In the transmission spectra of the filters 1a and 1b at an incident angle of 0 degrees, the maximum value T of the transmittance in the wavelength range of 300 to 380 nm is M 300-380 For example, it is 3% or less. As a result, the filter can easily and effectively absorb light in a wavelength region shorter than 400 nm. The maximum transmittance T M 300-380 It is preferably 2% or less, and more preferably 1% or less.

[0115] In the transmission spectrum of the filters 1a and 1b at an incident angle of 0 degrees, the wavelength at which the transmittance is 50% in the wavelength range of 300 to 520 nm is defined as the ultraviolet cutoff wavelength λ. UV For example, the filter 1a and the filter 1b satisfy 405nm≤λ UV ≤500nm. As a result, the light absorbing film 10 can easily and effectively absorb light in the short wavelength region near 410nm, and in an imaging device used in combination with an imaging element, it can easily cut off light in the wavelength region that is difficult for humans to recognize. The filters 1a and 1b preferably satisfy 405nm≤λ UV≤490nm, more preferably 405nm≤λ UV ≤480nm condition.

[0116] In the transmission spectrum of the filters 1a and 1b at an incident angle of 0 degrees, the minimum transmittance T in the wavelength range of 480 to 600 nm is m 480-600 For example, it is 85% or more. Thus, the optical filters 1a and 1b can appropriately transmit visible light, and in an image pickup device used in combination with an image pickup element, it is possible to increase the amount of light flux reaching the image pickup element from the subject.

[0117] Minimum transmittance T m 480-600 It is preferably 86% or more, and more preferably 87% or more.

[0118] The transmission spectrum obtained by allowing light in the wavelength range of 300nm to 1200nm to be incident on filters 1a and 1b at an incident angle of 0° can satisfy the following conditions (ia), (ii-a), (iii-a), (iv-a), (va) and (vi-a).

[0119] (ia) Maximum value T of transmittance in the wavelength range of 300nm to 380nm M 300-380 Less than 3%.

[0120] (ii-a) Transmittance T at a wavelength of 400 nm 400 Less than 5%.

[0121] (iii-a) Transmittance T at a wavelength of 410 nm 410 Less than 10%.

[0122] (iv-a) In the wavelength range of 350nm to 500nm, the wavelength λ at which the transmittance is 50% UV [nm] exists in the range of 405nm to 490nm.

[0123] (va) Minimum transmittance T in the wavelength range of 480 to 600 nm m 480-600 More than 85%.

[0124] (vi-a) Wavelength (λ UV Transmittance T at +10)nm 0 UV+ Relative to wavelength (λ UV -10)nm transmittance T 0 UV- Ratio T 0 UV+ / T0 UV- It is above 1.8.

[0125] By satisfying the above condition (ia), the optical filters 1a and 1b can exhibit high ultraviolet light absorptivity.

[0126] By satisfying the above conditions (ii-a) and (iii-a) in addition to the condition (ia), the filters 1a and 1b can exhibit higher ultraviolet absorption. In particular, the filters 1a and 1b are suitable for applications requiring filters with higher ultraviolet absorption performance. Transmittance T 400 It is preferably 4% or less.

[0127] By satisfying the above condition (iv-a), the filters 1a and 1b can exhibit high ultraviolet absorption, and the spectrum perceived by the imaging element can easily match the spectrum corresponding to human visual sensitivity. UV Preferably, it is 420nm to 490nm, and more preferably 420nm to 450nm. In this case, purple fringing is easily suppressed in the obtained image. Purple fringing is a purple color bleeding that appears particularly at the outline of the subject. In addition, the transmittance of light in the visible light region of humans can be increased, making it easy to obtain a bright image.

[0128] By satisfying the above condition (va), the transmittance of light in the visible light region of humans is easily increased, and a bright image is easily obtained. In particular, the transmittance of the wavelength region corresponding to the maximum sensitivity in the human visual sensitivity curve is easily increased, and when people observe the image, they tend to feel that it is brighter.

[0129] By satisfying the above condition (vi-a), the wavelength λ UV The transmission spectrum near the (UV cut-off wavelength) changes dramatically, so that ultraviolet rays that are invisible to humans can be shielded more dramatically, and the amount of light included in the visible light region can be increased. 0 UV+ / T 0 UV- It is preferably 1.9 or more, more preferably 2.0 or more, further preferably 2.2 or more, and particularly preferably 2.4 or more.

[0130] The reflection spectrum obtained by causing light in the wavelength range of 300nm to 1200nm to be incident on the optical filters 1a and 1b at an incident angle of 5° can satisfy the following conditions (ib) and (ii-b). In addition, the reflection spectrum obtained by causing light in the wavelength range of 300nm to 1200nm to be incident on the optical filters 1a and 1b at an incident angle of 40° can satisfy the following conditions (iii-b) and (iv-b). Furthermore, the reflection spectrum obtained by causing light in the wavelength range of 300nm to 1200nm to be incident on the optical filters 1a and 1b at an incident angle of 60° can satisfy the following conditions (vb) and (vi-b).

[0131] (ib) Maximum value R of reflectivity in the wavelength range of 300nm to 450nm 5 300-450 Less than 20%.

[0132] (ii-b) Maximum value R of reflectance in the wavelength range of 300 nm to 600 nm 5 300-600 Less than 25%.

[0133] (iii-b) Maximum value R of reflectivity in the wavelength range of 300 nm to 450 nm 40 300-450 Less than 20%.

[0134] (iv-b) Maximum value R of reflectivity in the wavelength range of 300 nm to 600 nm 40 300-600 Less than 25%.

[0135] (vb) Maximum value R of reflectivity in the wavelength range of 300nm to 450nm 60 300-450 Less than 30%.

[0136] (vi-b) Maximum value R of reflectivity in the wavelength range of 300 nm to 600 nm 60 300-600 Less than 35%.

[0137] Satisfying the above conditions (ib) to (vi-b) is very advantageous in terms of preventing the reflected light from the surfaces of the filters 1a and 1b from being reflected or refracted multiple times in, for example, the interior, edge, or lens surface of the camera module or housing and reaching the imaging element, thereby causing ghosting, flare, or noise. This is an advantage of using a light-absorbing filter as a filter for cutting off (shielding) ultraviolet rays. Maximum R 5 300-450 It is preferably 15% or less. 40 300-450It is preferably 15% or less. 60 300-450 It is preferably 20% or less. 5 300-600 It is preferably 20% or less. 40 300-600 It is preferably 20% or less. 60 300-600 It is preferably 25% or less.

[0138] The filters 1a and 1b can satisfy the following conditions (ic), (ii-c), (iii-c), (iv-c) and (vc). 30 UV [nm] is the wavelength at which the transmittance is 50% in the wavelength range of 350nm to 500nm in the transmission spectrum when light in the wavelength range of 300nm to 1200nm is incident on the filter at an incident angle of 30°. 40 UV [nm] is the wavelength at which the transmittance is 50% in the wavelength range of 350nm to 500nm in the transmission spectrum when light in the wavelength range of 300nm to 1200nm is incident on the filter at an incident angle of 40°. 50 UV [nm] is the wavelength at which the transmittance is 50% in the wavelength range of 350nm to 500nm in the transmission spectrum when light in the wavelength range of 300nm to 1200nm is incident on the filter at an incident angle of 50°. 60 UV [nm] is the wavelength at which the transmittance is 50% in the wavelength range of 350nm to 500nm in the transmission spectrum when light in the wavelength range of 300nm to 1200nm is incident on the filter at an incident angle of 60°. 70 UV [nm] is a wavelength at which the transmittance is 50% in the wavelength range of 350 nm to 500 nm in the transmission spectrum when light in the wavelength range of 300 nm to 1200 nm is incident on the filter at an incident angle of 70°.

[0139] (ic)|λ 30 UV -λ UV |≤2.4nm

[0140] (ii-c)|λ 40 UV -λ UV |≤3nm

[0141] (iii-c)|λ50 UV -λ UV |≤5nm

[0142] (iv-c)|λ 60 UV -λ UV |≤9nm

[0143] (vc)|λ 70 UV -λ UV |≤18nm

[0144] A completely absorbing type of ultraviolet cut-off filter can have the advantage of having a small angular dependence of the transmission spectrum. An ultraviolet cut-off filter of the type that uses a reflective film composed of a dielectric multilayer film to cut off ultraviolet rays has a tendency for the UV cut-off wavelength to shift to the short wavelength side for light incident from an oblique direction. Therefore, there is a possibility that the ultraviolet rays to be cut off can be detected by a sensor according to the angle of incidence. On the other hand, filters 1a and 1b satisfy the above-mentioned conditions (ic) to (vc), and the change in the UV cut-off wavelength for oblique incidence is small, and the UV cut-off wavelength is not easily shifted to the short wavelength side. Therefore, using filters 1a and 1b, in addition to the function of suppressing ghosting and light spots, it is also easy to achieve good color reproducibility that is not easy to produce color unevenness within the plane, and it is easy to obtain a high-quality image.

[0145] About (ic), |λ 30 UV -λ UV |Preferably satisfying |λ 30 UV -λ UV |≤1.6nm, preferably satisfying |λ 30 UV -λ UV |≤1.2nm. Regarding (ii-c), |λ 40 UV -λ UV |Preferably satisfying |λ 40 UV -λ UV |≤2.5nm, more preferably satisfying |λ 40 UV -λ UV |≤2nm. Regarding (iii-c), |λ 50 UV -λ UV |Preferably satisfying |λ 50 UV -λ UV |≤3.5nm, more preferably |λ 50 UV -λ UV|≤3nm. Regarding (iv-c), |λ 60 UV -λ UV |Preferably |λ 60 UV -λ UV |≤6nm, more preferably |λ 60 UV -λ UV |≤5nm. About (vc), |λ 70 UV -λ UV |Preferably |λ 70 UV -λ UV |≤12nm, more preferably |λ 70 UV -λ UV |≤9nm.

[0146] The optical filter 1a is, for example, composed of the light absorbing film 10 alone. In this case, the optical filter 1a can be used separately from the imaging element or the optical component, for example. The optical filter 1a can also be bonded to the imaging element and the optical component. On the other hand, the optical filter 1a can be formed by applying the above-mentioned light absorbing composition to the imaging element or the optical component and curing the light absorbing composition. In this way, the optical filter 1a can be manufactured by forming the light absorbing film 10 on the imaging element or the optical component.

[0147] The optical filter 1a can be manufactured, for example, by peeling off the light absorbing film 10 formed on a substrate from the substrate. In this case, the material of the substrate may be glass, resin, or metal. The surface of the substrate may be subjected to surface treatment such as coating with a fluorine-containing compound. In this way, the optical filter 1a can be manufactured by forming the light absorbing film 10 on a substrate and peeling off the light absorbing film 10 from the substrate.

[0148] like Figure 2A As shown in FIG. 1 , the optical filter 1b includes a light absorbing film 10 and a transparent dielectric substrate 20. The light absorbing film 10 is provided in parallel with one main surface of the transparent dielectric substrate 20. The light absorbing film 10 may, for example, be in contact with one main surface of the transparent dielectric substrate 20. In this case, the light absorbing film 10 may be formed, for example, by applying the above-mentioned light absorbing composition on one main surface of the transparent dielectric substrate 20 and curing the light absorbing composition.

[0149] The type of transparent dielectric substrate 20 is not limited to a specific type. The transparent dielectric substrate 20 may have an absorption capability in the infrared region. For example, the transparent dielectric substrate 20 may have an average spectral transmittance of 90% or more in a wavelength of 350nm to 900nm. The material of the transparent dielectric substrate 20 is not limited to a specific material, and may be, for example, a specified glass or resin. When the material of the transparent dielectric substrate 20 is glass, the transparent dielectric substrate 20 may be, for example, a transparent glass formed of silicate glass such as soda-lime glass and borosilicate glass, or a phosphate glass and a fluorophosphate glass containing coloring components such as Cu and Co. Phosphate glass and fluorophosphate glass containing coloring components are, for example, infrared absorbing glass, which itself has light absorption. When the light absorbing film 10 is used together with the transparent dielectric substrate 20 of infrared absorbing glass, the light absorption and transmission spectrum of both can be adjusted to produce a filter with desired optical characteristics, and the design freedom of the filter is high.

[0150] When the material of transparent dielectric substrate 20 is a resin, the resin is, for example, a cyclic olefin resin such as a norbornene resin, a polyarylate resin, an acrylic resin, a modified acrylic resin, a polyimide resin, a polyetherimide resin, a polysulfone resin, a polyethersulfone resin, a polycarbonate resin, or a silicone resin.

[0151] The optical filters 1a and 1b can be modified in a manner that they are further provided with other functional films such as infrared absorption films, infrared reflection films and anti-reflection films. Such functional films can be provided on the light absorption film 10 or the transparent dielectric substrate 20. For example, the optical filter is provided with an anti-reflection film, thereby being able to improve the transmittance in a specified wavelength range (e.g., the visible light region). The anti-reflection film can be formed as a layer of a low refractive index material such as MgF2 and SiO2, or as a laminate of a layer of such a low refractive index material and a layer of a high refractive index material such as TiO2, or as a dielectric multilayer film. Such an anti-reflection film can be formed by a method accompanied by a physical reaction such as vacuum evaporation and sputtering, or by a method accompanied by a chemical reaction such as a CVD method and a sol-gel method.

[0152] The optical filter can be formed, for example, in a state where a light absorbing film 10 is arranged between two plate-shaped glass sheets. In this case, the light absorbing film 10 represents a so-called intermediate film. As a result, the rigidity and mechanical strength of the optical filter are improved. In addition, the main surface of the optical filter becomes hard, which is advantageous from the perspective of preventing scratches, etc. In particular, when a resin with high flexibility is used as a binder or a base material in the light absorbing film 10, such an advantage is important.

[0153] By providing an antireflection film on the surface of the light absorbing film and the optical filter obtained by curing the light absorbing composition, it is possible to provide an optical filter having better optical characteristics. Figure 2B As shown, it is possible to provide an optical filter 1c having a light absorbing film 10 and an anti-reflection film 30. In an optical filter having an anti-reflection film, when light is incident on the optical filter at a predetermined incident angle, light reflected by the optical filter is reduced and significantly approaches zero. In this regard, in an imaging device equipped with an optical filter having an anti-reflection film, it is very advantageous from the viewpoint of preventing ghosting, flare, and noise caused by multiple scattering of reflected light, for example, in an imaging device or a camera module.

[0154] The material of the anti-reflection film is not limited to a specific material. The method for forming the anti-reflection film is not limited to a specific method. The method for forming the anti-reflection film may be a gas phase method or a liquid phase method. For example, the method for forming the anti-reflection film may be a vapor deposition method. The method for forming the anti-reflection film may be a sol-gel method using a reactive material containing silicon, which is an excellent liquid phase method for forming the anti-reflection film.

[0155] The anti-reflection film has the form of a single-layer film composed of the same material and a multilayer film composed of two or more different materials. The materials constituting the film and each layer of the multilayer film are not limited to specific materials. The material is, for example, an inorganic compound such as SiO2, TiO2, Ta2O3, MgF2, Al2O3, CaF2, ZrO2, CeO2 and ZnS. For example, when the anti-reflection film or the layer contained in the anti-reflection film contains SiO2, the film or layer can be formed by the so-called sol-gel method using an alkoxysilane compound as a starting material. Using the sol-gel method, the alkoxysilane compound can be hydrolyzed in the presence of water and a catalyst, and then polycondensed to obtain a dense and hard film containing SiO2. The sol-gel method has the advantage of being able to form a film or layer containing SiO2 without the need for high temperature.

[0156] When the anti-reflection film is formed using the sol-gel method, the starting material is not limited to a specific material, and the functional group possessed by the starting material is not limited to a specific functional group. The starting material preferably includes "trifunctional silanes containing alkyl groups" and "tetrafunctional silanes" such as MTES (methyltriethoxysilane) and TEOS (tetraethoxysilane). Tetrafunctional silanes are indispensable for forming a film or layer with a firm and dense skeleton. On the other hand, if only tetrafunctional silanes are used, it is difficult to control the reactivity and it is difficult to adjust the porosity of the film or layer. In addition, cracks are easily generated in the film or layer. If the starting material contains trifunctional silanes in addition to tetrafunctional silanes, the flexibility of the silica skeleton is improved, the porosity of the film or layer is easily adjusted, and cracks are easily suppressed in the film or layer. From the aspect of adjusting the refractive index of the anti-reflection film, it is preferably easy to adjust the porosity of the film or layer. The organic functional group in the trifunctional silane is not originally limited to a specific functional group. In particular, in order to form a uniform liquid and a coating film when combined with a tetrafunctional silane, a trifunctional silane having a methyl group as an organic functional group is preferred.

[0157] In the starting material, the ratio of the amount of "trifunctional silane containing an alkyl group" to the amount of "tetrafunctional silane" is not limited to a specific value. It is preferred that the relationship of the amount of "trifunctional silane containing an alkyl group" to the amount of "tetrafunctional silane" = 5:1 to 1:3 is satisfied in the starting material on a mass basis. As a result, cracks in the anti-reflection film can be easily suppressed, and a strong skeleton can be easily formed by tetrafunctional silane. The starting material may also contain components other than the components involved in the sol-gel method. For example, in order to adjust the refractive index, the starting material may contain microparticles and fillers. In this case, the microparticles and fillers may be hollow or may be high refractive index materials. The starting material may contain components that decompose at low temperatures. The refractive index of the anti-reflection film is thus easily adjusted. In the sol-gel method, the temperature at which the coating is fired is not limited to a specific temperature. The temperature is, for example, in the range of 60°C to 250°C, preferably in the range of 70°C to 230°C, and more preferably in the range of 80°C to 200°C.

[0158] When the anti-reflection film is a single-layer film, it is preferred that the refractive index of the material of the single-layer film is low. When the refractive index n1 of the material of the anti-reflection film is n1=√n0, the reflectivity tends to be the smallest. n0 is the refractive index of the substrate forming the anti-reflection film. For example, when the anti-reflection film comprises hollow particles formed of metal oxides such as SiO2 and TiO2 or organic materials such as PMMA, since air with a refractive index of about 1 occupies the interior of the hollow particles, the actual refractive index of the particles can be reduced, and the refractive index of the anti-reflection film tends to be reduced. The dielectric constant and refractive index of a mixture composed of two or more phases can be calculated by the effective medium approximation method using the Bruggemann formula. When the refractive index required for the anti-reflection film is not very low, the anti-reflection film may comprise solid particles formed of the above-mentioned materials. When mechanical strength such as scratch resistance is required in the anti-reflection film, it is advantageous for the anti-reflection film to comprise such solid particles. Film formation based on the sol-gel method may also be performed in a state containing such hollow particles or solid particles. In particular, when hollow particles or solid particles composed of SiO2 are used, the SiO2 in the film formed by the sol-gel method has good affinity with the hollow particles or solid particles, the aggregation of the hollow particles or solid particles is suppressed, and the suppression of seepage can be expected.

[0159] The anti-reflection film may have a multilayer film structure, which includes: a layer containing SiO2 formed by a sol-gel method; and a layer formed by, for example, a vacuum evaporation method, a sol-gel method, or other methods. For example, by forming a multilayer film of the anti-reflection film using two or more materials with different refractive indices, it is easy to ensure that the wavelength band in which the anti-reflection effect can be obtained is wide, and the minimum value of the reflectivity in the filter is easy to reduce. In the anti-reflection film, when a multilayer film structure is formed by combining with a layer containing SiO2 formed by a sol-gel method, the combined layer may be, for example, a layer containing hollow particles and formed by a sol-gel method, a layer formed by a material having a higher refractive index such as TiO2 and Ta2O3, or a layer formed by other materials such as MgF2.

[0160] Example

[0161] The present invention will be described in more detail by way of examples. It should be noted that the present invention is not limited to the following examples. First, the evaluation method of the optical filter of each example and each comparative example will be described.

[0162] <Measurement of Transmission Spectrum and Reflection Spectrum>

[0163] The transmission spectrum and reflection spectrum of each filter at a predetermined incident angle were measured using an ultraviolet-visible-near-infrared spectrophotometer (manufactured by JASCO Corporation, product name: V-670).

[0164] <Thickness measurement>

[0165] The distance from the surface of each filter was measured using a laser displacement meter (manufactured by KEYENCE Corporation, product name: LK-H008), and the thickness of the light absorbing film was measured by subtracting the thickness of the transparent glass substrate.

[0166] <Abrasion resistance test>

[0167] Kuraclean Wiper LF-8G manufactured by KURARAY Co., Ltd. was impregnated with ethanol, propylene glycol monomethyl ether (PGME) or propylene glycol monomethyl ether acetate (PGMEA) to obtain an alcohol-impregnated wipe. 2 The surface of the light-absorbing film was wiped 10 times back and forth over a length of about 3 cm while pressing the light-absorbing film obtained in each example and comparative example with a pressure of . The surface state of the light-absorbing film was then visually confirmed, and the case where there was no particular change was evaluated as "A", the case where scratches were confirmed on the surface was evaluated as "B", and the case where peeling of the light-absorbing film occurred was evaluated as "C". The results are shown in Table 8.

[0168] <Ultraviolet absorbing compound>

[0169] The following ultraviolet absorbing compounds were used in the preparation of the optical filters of Examples and Comparative Examples.

[0170] [Table 1]

[0171]

[0172] The structural formulas of the ultraviolet absorbing compounds (1-1) and (1-2) are represented by the following formulas (C) and (D), respectively.

[0173] [Chemistry 4]

[0174]

[0175] [Chemistry 5]

[0176]

[0177] <Compounds containing metal components>

[0178] In the production of the optical filters of Examples and Comparative Examples, materials containing the following metal components were used.

[0179] [Table 2]

[0180]

[0181] <Example 1>

[0182] 5.0 g of the ultraviolet absorber (1-1) shown in Table 1, 80.0 g of cyclohexanone as a solvent, and polyvinyl butyral (PVB) S-LECKS-10 (molecular weight 1.7×10 4 , acetalization degree 74 mol%, hydroxyl content 25 mol%) 8.0 g were mixed and stirred for 30 minutes. Then, 0.308 g of the material (2-1) containing the metal component shown in Table 2 was added to the obtained mixture, and the mixture was stirred for 30 minutes. 4.0 g of toluene diisocyanate (TDI) was further added to the obtained mixture, and the mixture was stirred for 30 seconds to obtain the light-absorbing composition of Example 1. The content of each component in the light-absorbing composition of Example 1, the mass ratio of the specified components, and the amount ratio of the specified components are shown in Tables 3 and 4. It should be noted that the mass ratio or amount ratio of the components of the light-absorbing composition of Example 1 was calculated on the premise that the content of the metal component in the material (2-1) containing the metal component was 6.5 mass % as shown in Table 2.

[0183] The light absorbing composition of Example 1 was spin-coated at 500 rpm (revolutions per minute) on one main surface of a transparent glass substrate (manufactured by SCHOTT, product name: D263T eco) made of borosilicate glass and having a size of 76 mm×76 mm×0.21 mm to form a coating film. The obtained coating film was fully dried at room temperature, and then placed in an oven and subjected to heat treatment at 140°C for 1 hour and at 160°C for 2 hours to cause a cross-linking reaction between PVB and TDI, thereby obtaining a light absorbing film of Example 1. In this way, an optical filter having a light absorbing film of Example 1 was produced. Figure 3 The transmission spectrum of the filter of Example 1 is shown in FIG. Figure 8 TABLE 5 Table 5 shows the reflection spectrum of the optical filter of Example 1. Table 5, Table 6 and Table 7 show the film thickness and optical characteristics of the light absorbing film of the optical filter of Example 1. Table 8 shows the results of the scratch resistance test of the light absorbing film of Example 1. Fig.13 : shows the transmission spectrum of the transparent glass substrate at an incident angle of 0 degrees.

[0184] <Examples 2 to 4>

[0185] The light-absorbing compositions of Examples 2 to 4 were prepared in the same manner as in Example 1, except that the amount of isocyanate added and / or the type of PVB were changed as shown in Table 3. The light-absorbing films and filters of Examples 2 to 4 were prepared in the same manner as in Example 1, except that the light-absorbing compositions of Examples 2 to 4 were used instead of the light-absorbing composition of Example 1. The PVB used in Example 4 was S-LECKS-1 (molecular weight 2.7×10 4, acetalization degree 74 mol%, hydroxyl content 25 mol%). The relevant values ​​of optical properties obtained by observing the transmission spectrum and reflection spectrum of the filter of Examples 2 to 4 are shown in Tables 5, 6 and 7. From these results, it can be understood that even if the mass ratio of the isocyanate in the light absorbing composition to the mass ratio of PVB varies within the range of 0.18 to 1.50, good optical properties can be obtained. The results of the scratch resistance test of the light absorbing film of Examples 2 to 4 are shown in Table 8.

[0186] <Examples 5 and 6>

[0187] The light absorbing compositions of Examples 5 and 6 were prepared in the same manner as in Example 1, except that the type of PVB and the type and amount of isocyanate added were changed as shown in Table 3. The light absorbing films and filters of Examples 5 and 6 were prepared in the same manner as in Example 1, except that the light absorbing compositions of Examples 5 and 6 were used instead of the light absorbing composition of Example 1. The PVB used in Example 5 was S-LECBX-L (molecular weight 1.8×10 4 , acetalization degree 67 mol%, hydroxyl content 32 mol%), the PVB used in Example 6 is S-LECBX-1 (molecular weight 10×10 4 , acetalization degree 72 mol %, hydroxyl content 27 mol %). The isocyanate used in Example 5 is diphenylmethane diisocyanate (MDI), and the isocyanate used in Example 6 is hexamethylene diisocyanate (HDI). Figure 4 The transmission spectrum of the filter of Example 5 is shown in FIG. Fig. 9 The reflection spectrum of the filter of Example 5 is shown in Table 5. The relevant values ​​of the optical characteristics of the filters of Examples 5 and 6 are shown in Table 5, Table 6 and Table 7. It can be understood from Examples 5 and 6 that good optical characteristics can be obtained even if MDI or HDI is used instead of TDI. The results of the scratch resistance test of the light absorbing films of Examples 5 and 6 are shown in Table 8.

[0188] <Examples 7 to 14>

[0189] The light-absorbing compositions of Examples 7 to 14 were prepared in the same manner as in Example 1, except that the type or amount of the ultraviolet absorbing compound, the material containing a metal component, PVB, or the isocyanate was changed as shown in Table 3. The light-absorbing films and filters of Examples 7 to 14 were prepared in the same manner as in Example 1, except that the light-absorbing compositions of Examples 7 to 14 were used instead of the light-absorbing composition of Example 1. The PVB used in Example 7 was S-LECBX-1 manufactured by Sekisui Chemical Co., Ltd. The PVB used in Example 8 was S-LECKS-1 manufactured by Sekisui Chemical Co., Ltd. The PVB used in Example 12 was S-LECBL-S (molecular weight 2.3×10 4 , acetalization degree 72 mol%, hydroxyl content 23 mol%). The PVB used in Example 13 was S-LECBL-1 (molecular weight 1.9×10 4 , acetalization degree 63 mol%, hydroxyl content 36 mol%). In Examples 9, 10, 11 and 14, S-LECKS-10 manufactured by Sekisui Chemical Co., Ltd. was used as PVB. Figure 5 , Figure 6 and Figure 7 Graphs 2 and 3 show the transmission spectra of the optical filters of Examples 7, 9 and 11, respectively. Fig.10 , Fig.11 as well as Fig.12 TABLE 5 Reflection spectra of the optical filters of Examples 7, 9 and 11 are shown in Table 5, Table 6 and Table 7. Table 8 shows the results of the scratch resistance test of the light absorbing films of Examples 7 to 14.

[0190] <Comparative Example 1>

[0191] The light-absorbing composition of Comparative Example 1 was prepared in the same manner as in Example 1 except that no isocyanate was added. The light-absorbing film and optical filter of Comparative Example 1 were prepared in the same manner as in Example 1 except that the light-absorbing composition of Comparative Example 1 was used instead of the light-absorbing composition of Example 1. The relevant values ​​of the optical properties of the optical filter of Comparative Example 1 are shown in Tables 5, 6, and 7. The results of the scratch resistance test of the light-absorbing film of Comparative Example 1 are shown in Table 8.

[0192] The optical filters of each of the examples and comparative example 1 have good optical properties from the viewpoint of reproducing human visual sensitivity. On the other hand, the comparison between the examples and the comparative examples suggests that by making the light-absorbing composition contain both PVB and isocyanate, good solvent resistance and scratch resistance can be easily obtained. In particular, it is suggested that if the mass ratio of the isocyanate in the light-absorbing composition to the mass ratio of PVB is 0.15 or more, good solvent resistance and scratch resistance can be easily obtained. From the perspective of good solvent resistance and scratch resistance, it is considered that the mass ratio of the isocyanate to the mass ratio of PVB is preferably 0.15 or more, and more preferably 0.18 or more. Regarding the upper limit of the mass ratio of the isocyanate to the mass ratio of PVB, it is considered that it is not limited to a specific value, but from the perspective of suppressing the curing of the light-absorbing composition immediately after the light-absorbing composition is applied due to the increase of isocyanate and facilitating the formation of a flat and uniformly thick light-absorbing film, it is considered that the ratio is preferably 1.50 or less. From the viewpoint of good optical properties, solvent resistance and scratch resistance, it is suggested that the mass ratio of the isocyanate to the mass ratio of the ultraviolet absorbing compound is preferably 0.3 or more, and the mass ratio is more preferably in the range of 0.3 to 2.4.

[0193] [Table 3]

[0194]

[0195] [Table 4]

[0196]

[0197] [Table 5]

[0198]

[0199] [Table 6]

[0200]

[0201] [Table 7]

[0202]

[0203] [Table 8]

[0204]

Claims

1. A light absorbing composition comprising: UV absorbing compounds having hydroxyl and carbonyl groups in the molecule; metal composition; Polyvinyl butyral; and Isocyanates, At least a portion of the metal component is bonded to the organic oxygen group.

2. The light-absorbing composition according to claim 1, wherein The content of the metal component in the light absorbing composition is 0.005% to 2% by mass.

3. The light-absorbing composition according to claim 1 or 2, wherein The content of the ultraviolet absorbing compound in the light absorbing composition is 0.1% to 20% by mass.

4. The light-absorbing composition according to any one of claims 1 to 3, wherein The ratio of the mass of the ultraviolet absorbing compound to the mass of the metal component is 5 to 300.

5. The light-absorbing composition according to any one of claims 1 to 4, wherein The ratio of the mass of the isocyanate to the mass of the polyvinyl butyral is 0.05 to 3.

0.

6. The light-absorbing composition according to any one of claims 1 to 5, wherein The ratio of the mass of the isocyanate to the mass of the ultraviolet absorbing compound is 0.1 to 3.

0.

7. The light-absorbing composition according to any one of claims 1 to 6, wherein The hydroxyl group and the carbonyl group are disposed with 1 to 3 atoms between them.

8. The light-absorbing composition according to any one of claims 1 to 7, wherein The ultraviolet absorbing compound includes a benzophenone compound represented by the following formula (A1), [Chemistry 1] In formula (A1), R 11 , R 12 , R 21 and R 22 At least one of them is a hydroxyl group; in formula (A1), R 11 , R 12 , R 21 or R 22 When a functional group other than a hydroxyl group exists, there are two or more R 11 , 2 or more R 12 , 2 or more R 21 , or 2 or more R 22 Also, R 11 , R 12 , R 21 and R 22 At least one of the may not exist.

9. The light-absorbing composition according to any one of claims 1 to 8, wherein The ultraviolet absorbing compound includes a benzophenone compound represented by the following formula (A2): [Chemistry 2] In formula (A2), R 31 is a hydrogen atom, a hydroxyl group, a carboxyl group, an aldehyde group, a halogen atom, a group having a halogen atom, an alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms; in formula (A2), R 41 and R 42 It may be a hydroxyl group, a carboxyl group, an aldehyde group, a group having a halogen atom, an alkyl group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms, R 41 and R 42 In formula (A2), there are two or more R 41 It is also possible that there are more than 2 R 42 Also acceptable.

10. The light-absorbing composition according to any one of claims 1 to 9, wherein The metal component includes at least one selected from the group consisting of Li, Na, Mg, Ca, Sr, Ba, Ge, Sn, Pb, Al, Ga, In, Tl, Zn, Cd, Cu, Ag, Au, Ni, Pd, Pt, Co, Rh, Ir, Fe, Mn, Cr, Mo, W, V, Nb, Ta, Ti and Zr.

11. A method for producing a light-absorbing composition according to any one of claims 1 to 10, wherein: The production method includes adding and mixing an ultraviolet absorbing compound having a hydroxyl group and a carbonyl group in a molecule, a compound containing a metal component, polyvinyl butyral, and isocyanate in an organic solvent.

12. A light absorbing film comprising: UV absorbing compounds having hydroxyl and carbonyl groups in the molecule; Metal content; and Resins having urethane bonds, At least a portion of the metal component is bonded to the organic oxygen group.

13. The light absorbing film according to claim 12, wherein The ratio of the mass of the ultraviolet absorbing compound to the mass of the metal component is 5 to 300.

14. The light-absorbing film according to claim 12 or 13, wherein The urethane bond is formed between the first site derived from polyvinyl butyral and the second site derived from isocyanate, The ratio of the mass of the isocyanate and the second site to the mass of the polyvinyl butyral and the first site is 0.05 to 3.

0.

15. The light-absorbing film according to any one of claims 12 to 14, wherein The urethane bond is formed between the first site derived from polyvinyl butyral and the second site derived from isocyanate, The ratio of the mass of the isocyanate and the second moiety to the mass of the ultraviolet absorbing compound is 0.1 to 3.

0.

16. The light-absorbing film according to any one of claims 12 to 15, wherein The hydroxyl group and the carbonyl group are disposed with 1 to 3 atoms between them.

17. The light-absorbing film according to any one of claims 12 to 16, wherein In the transmission spectrum with an incident angle of 0 degrees, the transmittance T at a wavelength of 400nm is 400 Less than 5%.

18. The light-absorbing film according to any one of claims 12 to 17, wherein The ultraviolet absorbing compound includes a benzophenone compound represented by the following formula (A1), [Chemistry 3] In formula (A1), R 11 , R 12 , R 21 and R 22 At least one of them is a hydroxyl group; in formula (A1), R 11 , R 12 , R 21 or R 22 When a functional group other than a hydroxyl group exists, there are two or more R 11 , 2 or more R 12 , 2 or more R 21 , or 2 or more R 22 Also, R 11 , R 12 , R 21 and R 22 At least one of the may not exist.

19. The light-absorbing film according to any one of claims 12 to 18, wherein The ultraviolet absorbing compound includes a benzophenone compound represented by the following formula (A2): [Chemistry 4] In formula (A2), R 31 is a hydrogen atom, a hydroxyl group, a carboxyl group, an aldehyde group, a halogen atom, a group having a halogen atom, an alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms; in formula (A2), R 41 and R 42 It may be a hydroxyl group, a carboxyl group, an aldehyde group, a group having a halogen atom, an alkyl group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms, R 41 and R 42 In formula (A2), there are two or more R 41 It is also possible that there are more than 2 R 42 Also acceptable.

20. The light-absorbing film according to any one of claims 12 to 19, wherein The transmission spectrum obtained by causing light in the wavelength range of 300 nm to 1200 nm to be incident on the light absorbing film at an incident angle of 0° satisfies the following conditions (ia), (ii-a), (iii-a), (iv-a), (va) and (vi-a), (ia) the maximum transmittance in the wavelength range of 300 nm to 380 nm is 3% or less, (ii-a) The transmittance at a wavelength of 400 nm is less than 5%, (iii-a) The transmittance at a wavelength of 410 nm is less than 10%, (iv-a) In the wavelength range of 350nm to 500nm, the wavelength λ at which the transmittance is 50% UV Exists in the range of 405nm to 490nm; (va) The minimum transmittance in the wavelength range of 480 to 600 nm is 85% or more; (vi-a) Wavelength (λ UV The transmittance at +10)nm is relative to the wavelength (λ UV The ratio of the transmittance at -10)nm is greater than 1.

8. 21 . An optical filter comprising the light-absorbing film according to claim 12 .

22. A method for producing an optical filter comprising the light-absorbing film according to any one of claims 12 to 20, wherein: The manufacturing method comprises the steps of any one of the following (i) or (ii), (i) forming the light absorbing film on an imaging element or an optical component; (ii) forming the light absorbing film on a substrate, and peeling the light absorbing film from the substrate.

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