Optical filter, imaging device and optical sensor

Abstract

To provide an optical filter which can effectively shield light of a long wavelength region of near infrared light, especially, of a wavelength region of 850 to 1,100 nm, and can keep transmittance of visible light, especially, transmittance of green and red to be sufficiently high, and an imaging device and an optical sensor which use the optical filter and are excellent in color reproducibility.SOLUTION: An optical filter has an absorption layer containing a transparent resin and a near-infrared absorption dye (A) in a wavelength region with a maximum absorption wavelength of 850 to 1,100 nm, and a dielectric multilayer film, and satisfies all of requirements (3-2) to (3-8).SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an optical filter that transmits light in the visible wavelength region and blocks light in the near-infrared wavelength region, and to an imaging device and an optical sensor that include the optical filter. [Background technology]

[0002] In order to reproduce color tones well and obtain clear images, imaging devices using solid-state imaging elements use optical filters that transmit light in the visible range (hereinafter also referred to as "visible light") and block light in the near-infrared range (hereinafter also referred to as "near-infrared light"). As such optical filters, near-infrared cut filters are known, which have an absorption layer containing a near-infrared absorbing dye and a resin, and a reflection layer made of a dielectric multilayer film that blocks near-infrared light, provided on a glass substrate.

[0003] Such near-infrared cut filters are used in applications such as ambient light sensors, and in such cases, they are required to absorb light in a specific long wavelength range of near-infrared light and have high transmittance in the visible light range.

[0004] As an optical filter for an ambient light sensor, for example, Patent Document 1 discloses an optical filter using a dye that has an absorption ability in the long wavelength region of near-infrared light, that is, wavelengths of 850 to 1050 nm.

[0005] Furthermore, Patent Document 2 describes a technology for a near-infrared cut filter that has good absorption characteristics in the long wavelength region of near-infrared light, can be easily produced in a small and thin shape, is less likely to produce micro-defects during polishing, and is excellent in cost and productivity, instead of absorbing glass that has absorption in the long wavelength region of near-infrared light. Patent Document 2 discloses a technology for obtaining a near-infrared cut filter with the above characteristics using an optical film containing a dye that is a combination of a diimonium dye, a cyanine dye, and an onium salt, and a transparent resin. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] International Publication No. 2017 / 094672 [Patent Document 2] Japanese Patent Publication No. 2008-303130 Summary of the Invention [Problem to be solved by the invention]

[0007] However, in the above-mentioned optical filter using an absorption layer containing a specific dye and a transparent resin that has absorption ability in the long wavelength region of near-infrared light, the transmittance of visible light, particularly the transmittance of green and red light that strongly affect visual perception, was not said to be sufficiently high.

[0008] The present invention aims to provide an optical filter that can effectively block light in the long wavelength region of near-infrared light, particularly light in the wavelength region of 850 to 1100 nm, while maintaining sufficiently high transmittance for visible light, particularly green and red light, and to provide an imaging device and optical sensor that use the optical filter and have excellent color reproducibility. [Means for solving the problem]

[0009] An optical filter according to one aspect of the present invention is an optical filter including a transparent resin, an absorption layer containing a near-infrared absorbing dye (A) having a maximum absorption wavelength in a wavelength region of 850 to 1100 nm, and a dielectric multilayer film, Meet all of the following requirements (3-2) to (3-8). (3-2) The optical characteristics measured at an incident angle of 0 degrees are the average transmittance T in the wavelength range of 490 to 560 nm. AVE490-560(0°) is over 82%. (3-3) The optical characteristics measured at an incident angle of 0 degrees are the average transmittance T in the wavelength range of 590 to 630 nm. AVE590-630(0°) is more than 50%. (3-4) Wavelength λ at which the transmittance is 50% at an incident angle of 0 degrees in the wavelength range of 600 to 800 nm 50%(0°) and the wavelength λ at which the transmittance is 50% at an incident angle of 30 degrees 50%(30°) The absolute value of the difference between |λ 50%(30°) -λ50%(0°) | is 5 nm or less. (3-5) Average transmittance T in the wavelength range of 490 to 560 nm measured at an incident angle of 30 degrees AVE490-560(30°) is more than 80%. (3-6) The maximum absorption wavelength λ of the near-infrared absorbing dye (A) measured at an incident angle of 30 degrees max(A)TR The minimum OD value in the wavelength range of ±10 nm is 3 or more. (3-7) Wavelength λ at which the transmittance is 50% at an incident angle of 0 degrees in the wavelength range of 600 to 800 nm 50%(0°) and the wavelength λ at which the transmittance is 50% at an incident angle of 50 degrees 50%(50°) The absolute value of the difference between |λ 50%(50°) -λ 50%(0°) | is 15 nm or less. (3-8) Average transmittance T in the wavelength range of 490 to 560 nm measured at an incident angle of 50 degrees AVE490-560(50°) is more than 70%.

[0010] The present invention also provides an imaging device and an optical sensor equipped with the optical filter of the present invention. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide an optical filter that can effectively block light in the long wavelength region of near-infrared light, particularly light in the wavelength region of 850 to 1100 nm, while maintaining sufficiently high transmittance for visible light, particularly for green and red light, and an imaging device and optical sensor that use the optical filter and have excellent color reproducibility. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a cross-sectional view schematically illustrating an example of an optical filter according to an embodiment. [Figure 2] FIG. 2 is a cross-sectional view schematically showing another example of the optical filter according to an embodiment. [Figure 3] FIG. 3 is a cross-sectional view schematically showing another example of the optical filter according to the embodiment. [Figure 4] FIG. 4 is a cross-sectional view schematically showing another example of the optical filter according to an embodiment. [Figure 5] FIG. 5 is a cross-sectional view schematically showing another example of the optical filter according to an embodiment. [Figure 6] FIG. 6 is a cross-sectional view schematically showing another example of the optical filter according to an embodiment. [Figure 7] FIG. 7 is a diagram showing the spectral transmittance curves of the dye (A1a-5NS) in Test Example 2 in the transparent resin P and in dichloromethane. [Figure 8] FIG. 8 is a diagram showing the spectral transmittance curves of the dye (A1a-5NS) in Test Example 19 in a transparent resin other than the transparent resin P and in dichloromethane. [Figure 9] FIG. 9 is a diagram showing the spectral transmittance curve of the absorption layer in the optical filter of the example (Example 1; Example). [Figure 10] FIG. 10 is a diagram showing the spectral transmittance curve of the optical filter of the example (Example 1; Example). [Figure 11] FIG. 11 is a diagram showing the spectral transmittance curve of the absorption layer in the optical filter of the example (Example 4; Example). [Figure 12] FIG. 12 is a diagram showing the spectral transmittance curve of the optical filter of the example (Example 4; Example). [Figure 13] FIG. 13 is a diagram showing the spectral transmittance curve of the absorption layer in the optical filter of the example (Example 6; Example). [Figure 14] FIG. 14 is a diagram showing the spectral transmittance curve of the optical filter of the example (Example 6; Example). [Figure 15] FIG. 15 is a diagram showing the spectral transmittance curve of the absorption layer in the optical filter of the example (Example 8; Comparative Example). [Figure 16] FIG. 16 is a diagram showing the spectral transmittance curve of the optical filter of the example (Example 8; Comparative Example). DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, an embodiment of the present invention will be described. In this specification, the near-infrared absorbing dye may be abbreviated as "NIR dye" and the ultraviolet absorbing dye may be abbreviated as "UV dye".

[0014] In this specification, a compound represented by formula (A1) is referred to as compound (A1). The same applies to compounds represented by other formulas. A dye consisting of compound (A1) is also referred to as dye (A1), and the same applies to other dyes. Furthermore, for example, a group represented by formula (1x) is also referred to as group (1x), and the same applies to groups represented by other formulas.

[0015] In this specification, internal transmittance is the transmittance obtained by subtracting the influence of interfacial reflection from the measured transmittance, as expressed by the formula: measured transmittance / (100-reflectance). In this specification, the transmittance of a transparent substrate made of resin and the transmittance of a resin layer, including those in which a dye such as an absorption layer is contained in the resin, are all "internal transmittance" even when they are referred to as "transmittance." On the other hand, the transmittance measured by dissolving a dye in a solvent such as dichloromethane and the transmittance of an optical filter having a dielectric multilayer film are measured transmittances.

[0016] In this specification, for example, a transmittance of 90% or more in a specific wavelength range means that the transmittance is not less than 90% across the entire wavelength range, i.e., the minimum transmittance is 90% or more across the wavelength range. Similarly, for example, a transmittance of 1% or less in a specific wavelength range means that the transmittance is not more than 1% across the entire wavelength range, i.e., the maximum transmittance is 1% or less across the wavelength range. The same applies to internal transmittance. The average transmittance and average internal transmittance in a specific wavelength range are the arithmetic mean of the transmittance and internal transmittance per 1 nm in the wavelength range. In this specification, the use of "to" to indicate a range of values ​​includes the upper and lower limits.

[0017] <Optical filters> An optical filter according to one embodiment of the present invention (hereinafter also referred to as "the filter") comprises a transparent resin (hereinafter also referred to as "transparent resin (P)") having a glass transition temperature (hereinafter also referred to as "Tg") of 130°C or higher, an absorption layer containing an NIR dye (A) that satisfies all of the requirements (1-1) to (1-6) below, and a reflective layer made of a dielectric multilayer film.

[0018] (1-1) Spectral transmittance curve SC at wavelengths of 350 to 1200 nm measured by incorporating NIR dye (A) into transparent resin (P) TR At the maximum absorption wavelength λ max(A)TR is in the wavelength range of 850 to 1100 nm. (1-2) Spectral transmittance curve SC TR Maximum absorption wavelength λ max(A)TR The average internal transmittance T of light with wavelengths of 490 to 560 nm when the internal transmittance at AVE490-560(A)TR is more than 90%.

[0019] (1-3) Spectral transmittance curve SC TR Maximum absorption wavelength λ max(A)TR The average internal transmittance T of light with wavelengths of 590 to 630 nm when the internal transmittance at AVE590-630(A)TR is more than 90%. (1-4) Spectral transmittance curve SC TR is the maximum absorption wavelength λ max(A)TR When the internal transmittance at 650 nm is 10%, there are two wavelengths in the wavelength region of 650 to 1150 nm at which the internal transmittance is 50%, and the width between the two wavelengths is 180 nm or more.

[0020] (1-5) Spectral transmittance curve SC at wavelengths of 350 to 1200 nm measured by dissolving NIR dye (A) in dichloromethane DCM Maximum absorption wavelength λ max(A)DCM The average transmittance T of light with wavelengths of 490 to 560 nm when the transmittance of light at 10% is AVE490-560(A)DCM from average internal transmittance T AVE490-560(A)TR The value obtained by subtracting is 10% or less. (1-6) Spectral transmittance curve SC DCM Maximum absorption wavelength λ max(A)DCMThe average transmittance T of light with wavelengths of 590 to 630 nm when the transmittance of light at AVE590-630(A)DCM from average internal transmittance T AVE590-630(A)TR The value obtained by subtracting is 10% or less.

[0021] This filter contains an NIR dye (A) and a transparent resin (P) whose absorption layer has the properties (1-1) to (1-6), and thus can effectively block light in the long wavelength region of near-infrared light, particularly light in the wavelength region of 850 to 1100 nm, while maintaining sufficiently high transmittance of visible light, particularly green and red. It is generally known that NIR dyes with maximum absorption wavelengths in the long wavelength region, due in part to aggregation, make it difficult to reproduce the high transmittance of visible light in dichloromethane in a transparent resin. As shown in (1-5) to (1-6) above, the NIR dye (A) maintains high transmittance of visible light in dichloromethane in relation to the transparent resin (P).

[0022] The NIR dye (A) preferably satisfies one or more of the following (1-7) to (1-9), more preferably two or more of them, and particularly preferably all of them.

[0023] (1-7) Spectral transmittance curve SC DCM Maximum absorption wavelength λ max(A)DCM The average transmittance T of light with wavelengths of 435 to 480 nm when the transmittance of light at 10% is AVE435-480(A)DCM From the spectral transmittance curve SC TR Maximum absorption wavelength λ max(A)TR The average internal transmittance T of light with wavelengths of 435 to 480 nm when the internal transmittance at AVE435-480(A)TR The value obtained by subtracting is 10% or less. (1-8) Average transmittance T AVE490-560(A)DCM from average internal transmittance T AVE490-560(A)TR The value obtained by subtracting is 5% or less. (1-9) Average transmittance T AVE590-630(A)DCM from average internal transmittance T AVE590-630(A)TR The value obtained by subtracting is 5% or less.

[0024] The filter may further include a transparent substrate. In this case, the absorbing layer and the reflective layer are provided on a major surface of the transparent substrate. The filter may include the absorbing layer and the reflective layer on the same major surface of the transparent substrate, or on different major surfaces. When the absorbing layer and the reflective layer are provided on the same major surface, the stacking order of these layers is not particularly limited.

[0025] The filter may also have other functional layers. Examples of such layers include an anti-reflection layer that suppresses loss of visible light transmittance. In particular, when the absorbing layer is configured as the outermost surface, a loss of visible light transmittance occurs due to reflection at the interface between the absorbing layer and air, so it is recommended to provide an anti-reflection layer on the absorbing layer.

[0026] Next, an example of the configuration of this filter will be described with reference to the drawings. FIG. 1 shows an example of the configuration of an optical filter 10A having a reflective layer 12 on one main surface of an absorbing layer 11. In the optical filter 10A, the absorbing layer 11 can be composed of a layer containing an NIR dye (A) and a transparent resin (P). The absorbing layer 11 may further contain an NIR dye (B) and / or an NIR dye (C) described below. In this case, the absorbing layer 11 may be composed of a plurality of laminated layers, each containing an appropriate combination of an NIR dye (A), an NIR dye (B), and / or an NIR dye (C). Note that "having a reflective layer 12 on one main surface (top) of the absorbing layer 11" does not necessarily mean that the reflective layer 12 is provided in contact with the absorbing layer 11, but also includes a case where another functional layer is provided between the absorbing layer 11 and the reflective layer 12, and the same applies to the following configurations.

[0027] 2 is a cross-sectional view schematically illustrating an example of an optical filter according to an embodiment having a transparent substrate, an absorption layer, and a reflection layer. Optical filter 10B has a transparent substrate 13, an absorption layer 11 disposed on one main surface of transparent substrate 13, and a reflection layer 12 disposed on the other main surface of transparent substrate 13. In optical filter 10B, absorption layer 11 can have the same configuration as optical filter 10A.

[0028] Fig. 3 shows an example of the configuration of an optical filter 10C that includes an absorption layer 11 and reflective layers 12a and 12b on both main surfaces of the absorption layer 11. Fig. 4 shows an example of the configuration of an optical filter 10D that includes an absorption layer 11 on one main surface of a transparent substrate 13 and reflective layers 12a and 12b on the other main surface of the transparent substrate 13 and on the main surface of the absorption layer 11. In the optical filters 10C and 10D, the absorption layer 11 can have the same configuration as that of the optical filter 10A.

[0029] FIG. 5 shows an example of the configuration of an optical filter 10E that includes absorbing layers 11a and 11b on both main surfaces of a transparent substrate 13, and further includes reflective layers 12a and 12b on the main surfaces of the absorbing layers 11a and 11b.

[0030] 3, 4, and 5, the two combined reflective layers 12a and 12b may be the same or different. For example, the reflective layers 12a and 12b may have the property of reflecting ultraviolet light and near-infrared light and transmitting visible light, and the reflective layer 12a may reflect ultraviolet light and light in the first near-infrared region, and the reflective layer 12b may reflect ultraviolet light and light in the second near-infrared region.

[0031] 5, at least one of the two absorption layers 11a and 11b has the above-described configuration of the present filter. The absorption layers 11a and 11b may be the same or different. When the absorption layers 11a and 11b are different, for example, the absorption layers 11a and 11b may each be a combination of a near-infrared absorption layer and an ultraviolet absorption layer, or a combination of an ultraviolet absorption layer and a near-infrared absorption layer.

[0032] Furthermore, in the optical filter 10E, when the absorption layers 11a and 11b contain, in addition to the NIR dye (A), the NIR dye (B) and / or NIR dye (C) described below, the NIR dyes contained in the absorption layers 11a and 11b can be appropriately combined. For example, when the optical filter 10E contains NIR dyes (A) to (C), one of the absorption layers 11a and 11b may contain one type selected from the NIR dyes (A) to (C), and the other may contain two types. Furthermore, the absorption layers 11a and 11b may each be a single layer or a laminate of multiple layers.

[0033] FIG. 6 shows an example of the configuration of an optical filter 10F in which an antireflection layer 14 is provided on the main surface of the absorption layer 11 of the optical filter 10B shown in FIG. 2. In cases where a reflection layer is not provided and the absorption layer is configured as the outermost surface, it is preferable to provide an antireflection layer on the absorption layer. The antireflection layer may be configured to cover not only the outermost surface of the absorption layer but also the entire side surface of the absorption layer. In this case, the moisture-proof effect of the absorption layer can be improved.

[0034] The absorbing layer, the reflective layer, the transparent substrate and the anti-reflection layer will be described below. (Absorption layer) The absorbing layer contains an NIR dye (A) having the properties (1-1) to (1-6) above, preferably further having one or more properties selected from the properties (1-7) to (1-9) above, and a transparent resin (P).

[0035] The absorbing layer is typically a layer or (resin) substrate in which the NIR dye (A) is uniformly dissolved or dispersed in a transparent resin (P). The absorbing layer may contain other NIR dyes in addition to the NIR dye (A) as long as the effects of the present invention are not impaired. Furthermore, the absorbing layer may contain dyes other than the NIR dye, particularly UV dyes, as long as the effects of the present invention are not impaired.

[0036] As other NIR dyes, NIR dye (B) having a maximum absorption wavelength in the wavelength region of 1100 to 1200 nm and NIR dye (C), which is a squarylium dye having a maximum absorption wavelength in the wavelength region of 630 to 750 nm, are preferred, respectively, in the spectral transmittance curve of 350 to 1200 nm measured after being incorporated into a transparent resin (P). Depending on the required characteristics of the present filter, the absorption layer may contain either or both of NIR dye (B) and NIR dye (C) in addition to NIR dye (A).

[0037] By containing the NIR dye (B), the absorption layer can absorb near-infrared light in a wavelength range longer than the absorption wavelength range of the NIR dye (A), and the absorption layer can obtain absorption in a wavelength range equivalent to that of absorbing glass. By containing the NIR dye (C), the absorption layer can reduce the influence of the incident angle dependency of the reflective layer made of a dielectric multilayer film in this filter.

[0038] [NIR dye (A)] The NIR dye (A) has a maximum absorption wavelength λ as defined in (1-1). max(A)TR The maximum absorption wavelength λ is in the wavelength range of 850 to 1100 nm. max(A)TR is preferably in the wavelength range of 900 to 1050 nm.

[0039] The NIR dye (A) is T AVE490-560(A)TR is 90% or more. AVE490-560(A)TR is preferably 92% or more, more preferably 94% or more. AVE590-630(A)TR is 90% or more. AVE590-630(A)TR is preferably 91% or more, and more preferably 94% or more.

[0040] The NIR dye (A) has a maximum absorption wavelength λ as defined in (1-4). max(A)TR Spectral transmittance curve SC when the internal transmittance is 10% TR has two wavelengths in the wavelength range of 650 to 1150 nm at which the internal transmittance is 50%, and the width W between the two wavelengths T50% is 180nm or more.T50% The wavelength on the short wavelength side of the wavelengths that account for 50% is preferably 650 nm or more, more preferably 700 nm or more. T50% The upper limit is preferably about 380 nm, more preferably about 370 nm, and even more preferably about 320 nm.

[0041] The NIR dye (A) is T AVE490-560(A)DCM -T AVE490-560(A)TR is 10% or less, and T AVE590-630(A)DCM -T AVE590-630(A)TR is less than 10%. AVE490-560(A)DCM -T AVE490-560(A)TR and T AVE590-630(A)DCM -T AVE590-630(A)TR are preferably 8% or less.

[0042] where T AVE490-560(A)DCM and T AVE590-630(A)DCM is the spectral transmittance curve SC of the NIR dye (A) in the wavelength range of 350 to 1200 nm measured by dissolving it in dichloromethane. DCM Maximum absorption wavelength λ max(A)DCM λ is the average transmittance of light with wavelengths of 490 to 560 nm and 590 to 630 nm, respectively, when the transmittance of light at λ is taken as 10%. max(A)DCM is preferably in the wavelength range of 850 to 1100 nm, and more preferably in the wavelength range of 900 to 1000 nm.

[0043] The NIR dye (A) is the T shown in (1-7) AVE435-480(A)DCM -T AVE435-480(A)TR is preferably 10% or less, more preferably 9% or less, and even more preferably 7% or less. AVE490-560(A)DCM -T AVE490-560(A)TR is preferably 5% or less, more preferably 4% or less, and even more preferably 3% or less. AVE590-630(A)DCM -T AVE590-630(A)TR is preferably 5% or less, more preferably 4% or less, and even more preferably 3% or less.

[0044] The molecular structure of the NIR dye (A) is not particularly limited as long as it satisfies the requirements (1-1) to (1-6) in relation to the transparent resin (P). Specific examples include at least one dye selected from the group consisting of cyanine dyes, croconium dyes, phthalocyanine dyes, squarylium dyes, diimonium dyes, tris-type immonium dyes, and diketopyrrolopyrrole dyes. Tris-type immonium dyes are particularly preferred from the viewpoint of high visible light transmittance and wide absorption layer width.

[0045] Specifically, the tris-type immonium dye that is the NIR dye (A) is preferably at least one selected from the compounds represented by the following formula (A1) and the compounds represented by the following formula (A2).

[0046] [ka]

[0047] The symbols in formulas (A1) and (A2) are as follows: R 201 ~R 206 and R 221 ~R 226 are each independently a hydrogen atom, a halogen atom, a sulfo group, a hydroxy group, a cyano group, a nitro group, a carboxyl group, a phosphate group, an alkyl group or alkoxy group having 1 to 20 carbon atoms which may have an oxygen atom between the carbon atoms and which may be substituted, an aryl group having 6 to 14 carbon atoms, an aralkyl group having 7 to 14 carbon atoms, or a heterocyclic group having 3 to 14 members which may be substituted, provided that groups in which a substituted or unsubstituted amino group is bonded to a phenyl group are excluded. 201 ~R 206 and R 221 ~R 226 In the formula (I), two groups bonded to the same nitrogen atom may be bonded to each other to form a heterocycle having 3 to 8 members together with the nitrogen atom, and a hydrogen atom bonded to the ring may be substituted with an alkyl group having 1 to 12 carbon atoms.

[0048] R207 ~R 218 and R 227 ~R 238 R are each independently a hydrogen atom, a halogen atom, an optionally substituted amino group, an amido group, a cyano group, a nitro group, a carboxyl group, or an optionally substituted alkyl or alkoxy group having 1 to 12 carbon atoms. 207 ~R 218 and R 227 ~R 238 In the formula, two adjacent groups may be bonded to each other to form a ring having 3 to 8 members together with two carbon atoms of the phenyl group, and a hydrogen atom bonded to the ring may be substituted with an alkyl group having 1 to 12 carbon atoms.

[0049] R 201 ~R 206 and R 221 ~R 226 In the formula (I), examples of the substituent in the optionally substituted alkyl or alkoxy group having 1 to 20 carbon atoms, the optionally substituted aryl group having 6 to 14 carbon atoms, the aralkyl group having 7 to 14 carbon atoms, or the heterocyclic group having 3 to 14 members include a halogen atom, a hydroxyl group, an amino group which may be substituted with an alkyl group having 1 to 6 carbon atoms, a carboxyl group, a sulfo group, a cyano group, and an acyloxy group having 1 to 6 carbon atoms.

[0050] R when no ring is formed 207 ~R 218 and R 227 ~R 238 are each independently preferably a hydrogen atom, a halogen atom, or an alkyl or alkoxy group having 1 to 12 carbon atoms. The alkyl or alkoxy group preferably has 1 to 6 carbon atoms, and more preferably has 1 to 4 carbon atoms.

[0051] R 207 ~R 218 and R 227 ~R 238In the formula (I), the ring formed by bonding two adjacent groups together with the two carbon atoms of the phenyl group may be an alicyclic ring, an aromatic ring, or a heterocyclic ring. Examples of heteroatoms include a nitrogen atom, an oxygen atom, and a sulfur atom.

[0052] R 207 ~R 218 and R 227 ~R 238 In Formula (A1) and Formula (A2), there are six combinations in total in which two adjacent groups are bonded to each other, two for each of the three phenyl groups bonded to the central nitrogen atom. 207 and R 208 , R 209 and R 210 , R 211 and R 212 , R 213 and R 214 , R 215 and R 216 , R 217 and R 218 In formula (A2), R 227 and R 228 , R 229 and R 230 , R 231 and R 232 , R 233 and R 234 , R 235 and R 236 , R 237 and R 238 There are six groups:

[0053] R in formula (A1) 207 ~R 218 and R in formula (A2) 227 ~R 238 In the formula, the number of pairs of adjacent groups bonded may be one, two or more, or up to six pairs may be bonded. Preferably, one pair is bonded to each of the three phenyl groups, for a total of three pairs.

[0054] Specific examples of the divalent group formed by bonding two adjacent groups include alkylene groups having 1 to 6 carbon atoms, which may contain 1 or 2 nitrogen atoms as heteroatoms and which may have an unsaturated bond between atoms. More specific examples include the following groups (X-1) to (X-4). Note that the hydrogen atoms in these divalent groups may be substituted with alkyl groups having 1 to 12 carbon atoms.

[0055] -(CH2) n -(n is an integer between 1 and 6) ...(X-1) -CH=CH-CH=CH- …(X-2) -CH2-CH=CH- …(X-3) -N=CH-NH- …(X-4)

[0056] R 207 ~R 218 and R 227 ~R 238 are each independently preferably a hydrogen atom, a halogen atom, or an alkyl or alkoxy group having 1 to 12 carbon atoms, more preferably a hydrogen atom, or an alkyl or alkoxy group having 1 to 12 carbon atoms. The alkyl or alkoxy group preferably has 1 to 6 carbon atoms, more preferably 1 to 4 carbon atoms.

[0057] Also, R 201 and R 207 , R 202 and R 210 , R 203 and R 211 , R 204 and R 214 , R 205 and R 215 , R 206 and R 218 , R 221 and R 227 , R 222 and R 230 , R 223 and R 231 , R 224 and R 234 , R 225 and R 235 , R 226 and R 238may be bonded to each other to form a 4-8 membered heterocycle together with the nitrogen atom bonded to the phenyl group and the two carbon atoms of the phenyl group, and a hydrogen atom bonded to the ring may be substituted with an alkyl group having 1 to 12 carbon atoms. Xa - and Xb - each independently represents a monovalent anion.

[0058] In the above, the alkyl group may be linear, branched, cyclic, or a combination of these structures. The same applies to the alkyl group when the aryl group below has an alkyl group, and the alkyl group of the aralkyl group below. Examples of halogen atoms include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms, with fluorine atoms and chlorine atoms being preferred.

[0059] In the above, the aryl group refers to a group that bonds via a carbon atom constituting an aromatic ring (not including a heteroatom) of an aromatic compound, such as a benzene ring, a naphthalene ring, biphenyl, etc. The aryl group also includes a structure in which a hydrogen atom bonded to a ring-constituting atom other than the carbon atom that contributes to the bond is substituted with an alkyl group, such as a tolyl group or a xylyl group.

[0060] In the above, the aralkyl group refers to a group in which an alkyl group is bonded to an aromatic ring (but does not contain a heteroatom) via a carbon atom constituting the alkyl group. The aralkyl group also includes a structure in which a hydrogen atom bonded to a ring-constituting atom other than the atom to which the alkyl group is bonded that contributes to the bond is substituted with an alkyl group.

[0061] In the above, the heterocyclic group is a group in which ring-constituting atoms are bonded via atoms constituting an alicyclic or aromatic ring composed of carbon atoms and atoms other than carbon atoms. The heterocyclic group includes a structure in which hydrogen atoms bonded to ring-constituting atoms other than the atoms contributing to the bond are substituted with alkyl groups. The atoms other than carbon atoms contained in the heterocyclic ring include oxygen atoms, nitrogen atoms, and sulfur atoms, and the number of atoms is preferably 1 to 2.

[0062] Xa- and Xb - As for each independently, Cl - , Br - , I - , F - , ClO4 - , BF4 - , PF6 - , SbF6 - , CF3SO3 - , CH3C6H4SO3 - , N[SO2R f ]2 - , C[SO2R f ]3 - etc.

[0063] where R f is a fluoroalkyl group having 1 to 4 carbon atoms, preferably a fluoroalkyl group having 1 to 2 carbon atoms, and more preferably a fluoroalkyl group having 1 carbon atom. When the number of carbon atoms is within the above range, durability such as heat resistance and moisture resistance, and solubility in organic solvents, which will be described later, are good. f Examples of the alkyl group include perfluoroalkyl groups such as -CF3, -C2F5, -C3F7, and -C4F9, and -C2F4H, -C3F6H, and -C2F8H.

[0064] From the viewpoint of moisture resistance, the fluoroalkyl group is preferably a perfluoroalkyl group, and more preferably a trifluoromethyl group.

[0065] Xa - and Xb - As for each, independently, I - , B.F. 4- , SbF6 - , PF6 - , ClO4 - , N[SO2CF3]2 - , C[SO2CF3]3 - etc. are preferred, and SbF6 is preferred because the difference in optical properties between the dichloromethane solution and the resin is small. - , PF6 - and N[SO2CF3]2 -is more preferred, SbF6 - , N[SO2CF3]2 - In addition, from the viewpoint of light durability, BF 4- , PF6 - , N[SO2CF3]2 - is preferred.

[0066] Dye (A1) was classified into three types of dyes (A1a) to (A1c) represented by the following formulas (A1a), (A1b), and (A1c), respectively, based on the structure of the group bonded to the nitrogen atom bonded to the 4th position of the three phenyl groups bonded to the central nitrogen atom. Dye (A2) was similarly classified into three types of dyes (A2a) to (A2c) represented by the following formulas (A2a), (A2b), and (A2c), respectively, based on the structure of the group bonded to the nitrogen atom bonded to the 4th position of the three phenyl groups bonded to the central nitrogen atom.

[0067] The dyes (A1a) and (A2a) have a structure in which the nitrogen atoms bonded to the 4-positions of the three phenyl groups (hereinafter referred to as the 4-position nitrogen atoms) do not form a heterocycle.

[0068] Dye (A1b) and dye (A2b) each have a structure in which at least one pair of two groups bonded to the three nitrogen atoms at position 4 are bonded to each other to form a heterocycle. Two pairs of two groups bonded to the three nitrogen atoms at position 4 may be bonded to each other, or all three pairs may be bonded to each other.

[0069] Dye (A1c) and dye (A2c) have a structure in which at least one of two groups bonded to three nitrogen atoms at the 4-position is bonded to a group bonded to the 3- or 5-position of a phenyl group to form a heterocycle. Dye (A1c) and dye (A2c) may have 2 to 6 such heterocycles.

[0070] [ka]

[0071] In formula (A1a) and formula (A2a), R 201~R 206 and R 221 ~R 226 are each independently a hydrogen atom, a halogen atom, a sulfo group, a hydroxy group, a cyano group, a nitro group, a carboxyl group, a phosphate group, an alkyl group or alkoxy group having 1 to 20 carbon atoms which may have an oxygen atom between the carbon atoms and which may be substituted, an aryl group having 6 to 14 carbon atoms, an aralkyl group having 7 to 14 carbon atoms, or a heterocyclic group having 3 to 14 members which may be substituted, provided that groups in which a substituted or unsubstituted amino group is bonded to a phenyl group are excluded. 201 ~R 206 and R 221 ~R 226 are each independently preferably an alkyl group having 1 to 12 carbon atoms, more preferably an alkyl group having 1 to 8 carbon atoms. 207 ~R 218 and R 227 ~R 238 are each independently R in formula (A1) and formula (A2). 207 ~R 218 and R 227 ~R 238 can be done in the same way.

[0072] [ka]

[0073] In formula (A1b), Q 1 , Q 2 and Q 3 is R in formula (A1) 201 and R 202 , R 203 and R 204 and R 205 and R 206 represents a divalent group in which Q are bonded to each other to form a heterocycle having 3 to 8 members together with the nitrogen atom to which they are bonded. 11 , Q 12 and Q 13 is R in formula (A2) 221 and R 222 , R 223 and R 224and R 225 and R 226 are bonded to each other to form a 3-8 membered heterocycle together with the nitrogen atom to which they are bonded.

[0074] Formula (A1b) and Formula (A2b) are Q 1 ~Q 3 and Q 11 ~Q 13 It is sufficient to have at least one of the above, but it may also have two or more, or even three. 1 ~Q 3 and Q 11 ~Q 13 The hydrogen atoms bonded to may be independently substituted with alkyl groups having 1 to 12 carbon atoms.

[0075] Q 1 ~Q 3 and Q 11 ~Q 13 are each independently -(CH2) n1 It is preferably an alkylene group represented by - (n1 is an integer of 2 to 7), and a hydrogen atom of the alkylene group may be substituted with an alkyl group having 1 to 12 carbon atoms.

[0076] When a heterocycle is not formed, R 201 ~R 206 and R 221 ~R 226 are each independently R in formula (A1a) and formula (A2a). 201 ~R 206 and R 221 ~R 226 This can be done in the same way as R 207 ~R 218 and R 227 ~R 238 are each independently R in formula (A1) and formula (A2). 207 ~R 218 and R 227 ~R 238 can be done in the same way.

[0077] [ka]

[0078] In formula (A1c), Q 4 ~Q 9 are R 201 and R 207 , R 202 and R 210 , R 203 and R 211 , R 204 and R 214 , R 205 and R 215 , R 206 and R 218 and Q are bonded to each other to form a 4-8-membered heterocycle together with the nitrogen atom to which they are bonded and the carbon atom of the phenyl group. 14 ~Q 19 are R 221 and R 227 , R 222 and R 230 , R 223 and R 231 , R 224 and R 234 , R 225 and R 235 , R 226 and R 238 are bonded to form a 4-8 membered heterocycle together with the nitrogen atom to which these groups are bonded and the carbon atom of the phenyl group.

[0079] Equations (A1c) and (A2c) are Q 4 ~Q 9 and Q 14 ~Q 19 It is sufficient to have at least one of the above, but it may also have two or more, and may have up to six. 4 ~Q 9 and Q 14 ~Q 19 The hydrogen atoms bonded to may be independently substituted with alkyl groups having 1 to 12 carbon atoms.

[0080] Q 4 ~Q 9 and Q 14 ~Q19 are each independently -(CH2) n2 It is preferably an alkylene group represented by - (n2 is an integer of 1 to 5), and a hydrogen atom of the alkylene group may be substituted with an alkyl group having 1 to 12 carbon atoms.

[0081] When a heterocycle is not formed, R 201 ~R 218 and R 221 ~R 238 are each independently R in formula (A1) and formula (A2). 201 ~R 218 and R 221 ~R 238 can be done in the same way.

[0082] More specifically, the dye (A1a) and the dye (A2a) are each R 201 ~R 218 and R 221 ~R 238 Examples of the dye (A1a) include the compounds shown in Tables 1 and 2 below. 201 , R 203 , R 205 Since they have the same groups as R, they are shown together in one column in Table 1. 202 , R 204 , R 206 The same is true for R. 207 ~R 218 In the case of the three phenyl groups bonded to the central nitrogen atom, the substituents at the same positions are collectively referred to as "R 207 , R 211 , R 215 "," "R 208 , R 212 , R 216 "," "R 209 , R 213 , R 217 "," "R 210 , R 214 , R 218 The same notation method was used for the dye (A2a).

[0083] In Table 1, for the dyes (A1a-21) and (A1a-23), three pairs of adjacent two groups, R 207 and R 208 , R 211 and R 212 , and R 215 and R 216 The divalent group formed by bonding these groups is referred to as "R 207 , R 211 , R 215 " column and "R 208 , R 212 , R 216 For dye (A1a-22), three pairs of adjacent two groups, R 209 and R 210 , R 213 and R 214 , and R 217 and R 218 The divalent group formed by bonding these groups is referred to as "R 209 , R 213 , R 217 " column and "R 210 , R 214 , R 218 The same notation method was used for dyes (A2a-21), dyes (A2a-22), and dyes (A2a-23) in Table 2.

[0084] Tables 1 and 2 show Xa - and Xb - However, in all compounds, Xa - or Xb - are each independently Cl - , Br - , I - , F - , ClO4 - , BF4 - , PF6 - , SbF6 - , CF3SO3 - , CH3C6H4SO3 - , N[SO2R f ]2 - , or C[SO2R f ]3 - Xa - and Xb- are each independently - , B.F. 4- , SbF6 - , PF6 - , ClO4 - , N[SO2CF3]2 - or C[SO2CF3]3 - is preferred.

[0085] The abbreviations of the dyes corresponding to the above preferred monovalent anions are as follows: - But, I - In the case of dye (A1a-1I), BF 4- In the case of dye (A1a-1B), SbF6 - In the case of dye (A1a-1Sb), PF6 - In the case of dye (A1a-1P), ClO4 - In the case of dye (A1a-1Cl), N[SO2CF3]2 - In the case of dye (A1a-1NS), C[SO2CF3]3 - This case is referred to as dye (A1a-1CS). The same applies to the other dyes shown in Tables 1 and 2. In Tables 1 and 2, Ph represents a phenyl group, and all alkyl groups such as -C3H7 are linear alkyl groups.

[0086] [Table 1]

[0087] [Table 2]

[0088] More specifically, the dye (A1b) is 1 ~Q 3 , R 207 ~R 218 The compounds shown in Table 3 below are examples of dye (A1b). 1 , Q 2 , Q 3 Since they have the same groups as R, they are shown together in one column in Table 3.207 ~R 218 The same descriptions as in Table 1 are used for the dye (A2b). More specifically, Q 11 ~Q 13 , R 227 ~R 238 Examples of the dye (A2b) include the compounds shown in Table 4 below. 11 , Q 12 , Q 13 Since they have the same groups as R, they are shown together in one column in Table 4. 227 ~R 238 The same information is used as in Table 2.

[0089] Tables 3 and 4 show Xa - and Xb - However, in all compounds, Xa - or Xb - is the same as that of the dye (A1a) shown in Table 1. In Tables 3 and 4, all alkyl groups such as -C4H9 are linear alkyl groups.

[0090] [Table 3]

[0091] [Table 4]

[0092] More specifically, the pigment (A1c) is Q 4 ~Q 9 , "R 202 , R 204 , R 206 "," "R 208 , R 212 , R 216 "," "R 209 , R 213 , R 217 "," "R 210 , R 214 , R 218 " are shown in Table 5 below. In the example dye (A1c), Q 4 , Q6 , Q 8 In Table 5, these are shown together in one column. 5 , Q 7 , Q 9 If Q has 5 , Q 7 , Q 9 Since they have the same groups as "R" and "R" in Table 5, they are shown together in one column. 202 , R 204 , R 206 " and "R 210 , R 214 , R 218 " is a pigment (A1c), Q 5 , Q 7 , Q 9 is a group that is present when

[0093] More specifically, the dye (A2c) is 14 ~Q 19 , "R 222 , R 224 , R 226 "," "R 228 , R 232 , R 236 "," "R 229 , R 233 , R 237 "," "R 230 , R 234 , R 238 " are shown in Table 6 below. In the example dye (A2c), Q 14 , Q 16 , Q 18 In Table 6, these are shown together in one column. 15 , Q 17 , Q 19 If Q has 15 , Q 17 , Q 19 Since they have the same groups as "R" and "R" in Table 6, they are shown together in one column. 222 , R 224 , R 226 " and "R 230 , R 234 , R 238 " indicates that the pigment (A2c) is Q15 , Q 17 , Q 19 is a group that is present when

[0094] "R 202 , R 204 , R 206 "," "R 208 , R 212 , R 216 "," "R 209 , R 213 , R 217 "," "R 210 , R 214 , R 218 " is described in the same way as in Table 1. "R 222 , R 224 , R 226 "," "R 228 , R 232 , R 236 "," "R 229 , R 233 , R 237 "," "R 230 , R 234 , R 238 " is described in the same way as in Table 2.

[0095] In addition, in the dye (A1c) and the dye (A2c), a compound having a symmetrical structure, for example, the dye (A1c-1) and the compound having a “Q 5 , Q 7 , Q 9 " is -CH2-CH2-CH2-CH2- and "R 201 , R 203 , R 205 " is -C2H5 and "R 207 , R 211 , R 215 "," "R 208 , R 212 , R 216 "," "R 209 , R 213 , R 217 " is treated as the same compound as a compound where is H.

[0096] Tables 5 and 6 show Xa - and Xb - However, in all compounds, Xa - or Xb- is the same as that of the dye (A1a) shown in Table 1. In Tables 5 and 6, all alkyl groups such as -C3H7 are linear alkyl groups. 4 , Q 6 , Q 8 "," Q 5 , Q 7 , Q 9 "," Q 14 , Q 16 , Q 18 ", and "Q 15 , Q 17 , Q 19 The divalent groups shown in the "" column are bonded to a nitrogen atom on the left side and to a carbon atom of a phenyl group on the right side.

[0097] [Table 5]

[0098] [Table 6]

[0099] As the dye (A1), among these, as the dye (A1a), the dye (A1a-5Sb), the dye (A1a-5NS), the dye (A1a-5P), the dye (A1a-5Cl), the dye (A1a-5B), the dye (A1a-1NS), the dye (A1a-4Sb), the dye (A1a-4NS), the dye (A1a-4P), the dye (A1a-7NS), the dye (A1a-7P), and the like are preferred, and the dye (A1a-5Sb), the dye (A1a-5NS), the dye (A1a-5P), the dye (A1a-4Sb), the dye (A1a-4NS), and the dye (A1a-4P) are more preferred.

[0100] Furthermore, the dye (A1b) is preferably the dye (A1b-1Sb), the dye (A1b-1NS), the dye (A1b-1P), etc. The dye (A1c) is preferably the dye (A1c-3NS), the dye (A1c-3P), the dye (A1c-4NS), the dye (A1c-4P), the dye (A1c-10NS), the dye (A1c-10P), etc., and more preferably the dye (A1b-1NS), the dye (A1b-1NS), the dye (A1c-4NS), the dye (A1c-4P), the dye (A1c-10NS), and the dye (A1c-10P).

[0101] Among these, as the dye (A2a), the dye (A2a-5Sb), the dye (A2a-5NS), the dye (A2a-5P), the dye (A2a-5Cl), the dye (A2a-5B), the dye (A2a-1NS), the dye (A2a-4Sb), the dye (A2a-4NS), the dye (A2a-4P), the dye (A2a-7NS), the dye (A2a-7P), and the like are preferred, and the dye (A2a-5Sb), the dye (A2a-5NS), the dye (A2a-5P), the dye (A2a-4Sb), the dye (A2a-4NS), and the dye (A2a-4P) are more preferred.

[0102] As the dye (A2b), dye (A2b-1Sb), dye (A2b-1NS), dye (A2b-1P), etc. are preferred. As the dye (A2c), dye (A2c-3NS), dye (A2c-3P), dye (A2c-4NS), dye (A2c-4P), dye (A2c-10NS), dye (A2c-10P), etc. are preferred, and dye (A2b-1NS), dye (A2b-1NS), dye (A2c-4NS), dye (A2c-4P), dye (A2c-10NS), dye (A2c-10P) are more preferred.

[0103] The NIR dye (A) may consist of one compound or two or more compounds. When consisting of two or more compounds, each compound does not necessarily have to have the properties of the NIR dye (A), but the NIR dye (A) as a mixture may have the properties of the NIR dye (A).

[0104] The dye (A1) and the dye (A2) can be produced by known methods. The dyes (A1a) to (A1c) can be produced, for example, by the method described in JP-A-2007-197492. The dyes (A2a) to (A2c) can be produced, for example, by the method described in JP-A-2009-221146.

[0105] [NIR dye (B)] The NIR dye (B) has a maximum absorption wavelength λ in the wavelength range of 1100 to 1200 nm in the spectral transmittance curve of 350 to 1200 nm measured by incorporating it into the transparent resin (P). max(B)TR It is a dye having a maximum absorption wavelength λ max(B)TR is preferably in the wavelength range of 1100 to 1150 nm.

[0106] The NIR dye (B) preferably also has a high visible transmittance in the resin.

[0107] For NIR dye (B), the maximum absorption wavelength λ max(B)TR The molecular structure is not particularly limited as long as the wavelength is in the range of 1100 to 1200 nm. Specific examples include at least one dye selected from the group consisting of cyanine dyes, croconium dyes, phthalocyanine dyes, squarylium dyes, diimonium dyes, diketopyrrolopyrrole dyes, metal complex dyes, and metal oxides, and diimonium dyes are particularly preferred from the viewpoint of high visible light transmittance.

[0108] Specifically, the diimonium dye that is the NIR dye (B) is preferably at least one selected from the compounds represented by the following formula (B1) and the compounds represented by the following formula (B2).

[0109] [ka]

[0110] The symbols in formulas (B1) and (B2) are as follows: R 241 ~R 248 and R261 ~R 268 are each independently a hydrogen atom, a halogen atom, a sulfo group, a hydroxy group, a cyano group, a nitro group, a carboxyl group, a phosphate group, an alkyl group or alkoxy group having 1 to 20 carbon atoms which may have an unsaturated bond or an oxygen atom between carbon atoms and which may be substituted, an aryl group having 6 to 14 carbon atoms, an aralkyl group having 7 to 14 carbon atoms, or a heterocyclic group having 3 to 14 members, which may be substituted. 241 ~R 248 and R 261 ~R 268 In the formula (I), two groups bonded to the same nitrogen atom may be bonded to each other to form a heterocycle having 3 to 8 members together with the nitrogen atom, and a hydrogen atom bonded to the ring may be substituted with an alkyl group having 1 to 12 carbon atoms.

[0111] R 241 ~R 248 and R 261 ~R 268 In the formula (I), examples of the substituent in the optionally substituted alkyl or alkoxy group having 1 to 20 carbon atoms, the optionally substituted aryl group having 6 to 14 carbon atoms, the aralkyl group having 7 to 14 carbon atoms, or the heterocyclic group having 3 to 14 members include a halogen atom, a hydroxyl group, an amino group which may be substituted with an alkyl group having 1 to 6 carbon atoms, a carboxyl group, a sulfo group, a cyano group, and an acyloxy group having 1 to 6 carbon atoms.

[0112] R when no ring is formed 241 ~R 248 and R 261 ~R 268 are each independently preferably an alkyl group or alkoxy group having 1 to 12 carbon atoms. The alkyl group or alkoxy group preferably has 1 to 8 carbon atoms.

[0113] R 241 ~R 248 and R 261 ~R 268As the alkyl group, a linear or branched alkyl group having 4 to 6 carbon atoms is preferred from the following viewpoint: By making the alkyl group have 4 or more carbon atoms, the solubility in organic solvents becomes good, and by making the alkyl group have 6 or less carbon atoms, the heat resistance is improved. The reason for the improved heat resistance is thought to be that the melting point of the dye increases.

[0114] A divalent group formed when two groups bonded to the same nitrogen atom are bonded to each other, i.e., R 241 and R 242 , R 243 and R 244 , R 245 and R 246 , R 247 and R 248 When these are bonded together, the divalent group is -(CH2) n3 It is preferably an alkylene group represented by - (n3 is an integer of 2 to 7), and a hydrogen atom of the alkylene group may be substituted with an alkyl group having 1 to 12 carbon atoms.

[0115] R 249 ~R 253 and R 269 ~R 273 are each independently a hydrogen atom, a halogen atom, an optionally substituted amino group, an amido group, a cyano group, a nitro group, a carboxyl group, or an alkyl group or alkoxy group having 1 to 12 carbon atoms which may be substituted with a halogen atom. 249 ~R 253 , R 269 ~R 273 may be the same or different.

[0116] R 249 ~R 253 and R 269 ~R 273 are each independently preferably a hydrogen atom, a halogen atom, or an alkyl or alkoxy group having 1 to 12 carbon atoms. The alkyl or alkoxy group preferably has 1 to 6 carbon atoms, and more preferably has 1 to 4 carbon atoms.

[0117] Xc - and Xd -Each independently represents a monovalent anion. - and Xd - Examples include Cl - , Br - , I - , F - , ClO4 - , BF4 - , PF6 - , SbF6 - , CF3SO3 - , CH3C6H4SO3 - , N[SO2R f ]2 - , C[SO2R f ]3 - Among these, PF6 - , N[SO2R f ]2 - , C[SO2R f ]3 - is preferred, and PF6 - , N[SO2R f ]2 - is more preferred.

[0118] where R f is the above Xa - and Xb - The same can be done in the case of (1) including the preferred embodiment.

[0119] More specifically, the dye (B1) and the dye (B2) are each R 241 ~R 253 and R 261 ~R 273 Examples of the dye (B1) include the compounds shown in Tables 7 and 8. 241 , R 243 , R 245 , R 247 Since they have the same groups as R, they are shown together in one column in Table 7. 242 , R 244 , R 246 , R 248 The same is true for R. 249 4~R 253 For 4, R 249 ~R 253indicates that each has four groups or atoms, and if the four groups or atoms are the same, only one of the groups or atoms is listed. If they are different, the four atoms or groups are listed, such as "H,H,H,-CH3." The position to which the atom or group is attached is not specified. For example, "H,H,H,-CH3" indicates that -CH3 is attached to any of the four carbon atoms other than the carbon atom to which the nitrogen atom of the benzene ring is attached.

[0120] In Table 7, dye (B1-6) is R 241 and R 242 , R 243 and R 244 , R 245 and R 246 , R 247 and R 248 are bonded to form -CH2-CH2-CH2-CH2-. The description method for dye (B1) in Table 7 is also applied to dye (B2) in Table 8.

[0121] Tables 7 and 8 show Xc - and Xd - Although no compound exhibits Xc - or Xd - are each independently Cl - , Br - , I - , F - , ClO4 - , BF4 - , PF6 - , SbF6 - , CF3SO3 - , CH3C6H4SO3 - , N[SO2R f ]2 - , or C[SO2R f ]3 - Xc - and Xd - are each independently - , B.F. 4- , SbF6 - , PF6 - , ClO4 - , N[SO2CF3]2 -or C[SO2CF3]3 - is preferred.

[0122] The abbreviations of the dyes corresponding to the above preferred monovalent anions are as follows: For example, in dye (B1-1), Xc - But, I - In the case of dye (B1-1I), BF 4- In the case of dye (B1-1B), SbF6 - In the case of dye (B1-1Sb), PF6 - In the case of dye (B1-1P), ClO4 - In the case of dye (B1-1Cl), N[SO2CF3]2 - In the case of dye (B1-1NS), C[SO2CF3]3 - This case is referred to as dye (B1-1CS). The same applies to the other dyes shown in Tables 7 and 8. In Tables 7 and 8, Ph represents a phenyl group, and all alkyl groups such as -C3H7 are linear alkyl groups.

[0123] [Table 7]

[0124] [Table 8]

[0125] Among these, the dye (B1) is preferably the dye (B1-5NS), the dye (B1-5Sb), the dye (B1-5P), the dye (B1-4NS), the dye (B1-4Sb), the dye (B1-4P), etc. Among these, the dye (B2) is preferably the dye (B2-4NS), the dye (B2-4P), the dye (B2-5NS), the dye (B2-5P), etc.

[0126] The NIR dye (B) may consist of one compound or two or more compounds. When consisting of two or more compounds, each compound does not necessarily have the properties of the NIR dye (B), but the NIR dye (B) as a mixture may have the properties of the NIR dye (B).

[0127] The dye (B1) and the dye (B2) can be produced by known methods. The dye (B1) can be produced by the method described in JP-A-2009-137894, for example. The dye (B2) can be produced by the method described in JP-A-2000-229931, for example.

[0128] Examples of commercially available dyes (B1) include Kayasorb IRG-022, IRG-023, IRG-024, IRG-068, IRG-069, and IRG-079 manufactured by Nippon Kayaku Co., Ltd., and CIR-1081, CIR-1083, CIR-1085, and CIR-RL (all trade names) manufactured by Nippon Carlit Co., Ltd.

[0129] [NIR dye (C)] The NIR dye (C) has a maximum absorption wavelength λ in the wavelength range of 630 to 750 nm in the spectral transmittance curve of 350 to 1200 nm measured by incorporating it into the transparent resin (P). max(C)TR It is a squarylium dye having a maximum absorption wavelength λ max(c)TR is preferably in the wavelength range of 650 to 740 nm.

[0130] Furthermore, NIR dye (C) has high visible transmittance in resin and a maximum absorption wavelength λ max(C)TR When the transmittance increases from the upper wavelength side to the shorter wavelength side, it is preferable that the transmittance rises sharply.

[0131] The NIR dye (C) has a maximum absorption wavelength λ max(C)TR There are no particular limitations on the squarylium dye as long as it satisfies the above requirements. More specifically, the NIR dye (C) is preferably a squarylium dye represented by the following formula (I) or (II):

[0132] [ka]

[0133] In the formula (I), the symbols are as follows: R 24 and R 26 are each independently a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group or an alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 1 to 10 carbon atoms, an aryl group having 6 to 11 carbon atoms, an aralkyl group having 7 to 18 carbon atoms which may have a substituent and which may have an oxygen atom between the carbon atoms, -NR 27 R 28 (R 27 and R 28 are each independently a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, or -C(=O)-R 29 (R 29 represents a hydrogen atom, a halogen atom, a hydroxyl group, a hydrocarbon group having 1 to 25 carbon atoms which may have a substituent and which may contain an unsaturated bond between carbon atoms, an oxygen atom, or a saturated or unsaturated ring structure), -NHR 30 , or -SO2-R 30 (R 30 represents a hydrocarbon group having 1 to 25 carbon atoms, each of which may have one or more hydrogen atoms substituted with a halogen atom, a hydroxyl group, a carboxyl group, a sulfo group, or a cyano group, and which may contain an unsaturated bond, an oxygen atom, or a saturated or unsaturated ring structure between carbon atoms), or a group represented by the following formula (S): 41 , R 42 are independently a hydrogen atom, a halogen atom, or an alkyl or alkoxy group having 1 to 10 carbon atoms. k is 2 or 3.

[0134] [ka]

[0135] R 21 and R 22 , R 22 and R 25 , and R 21 and R 23 may be linked to each other to form, together with the nitrogen atom, 5- or 6-membered heterocycles A, B, and C, respectively.

[0136] R when heterocycle A is formed 21and R 22 represents a divalent group -Q- to which they are bonded, which is an alkylene group or alkyleneoxy group in which a hydrogen atom may be substituted with an alkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 10 carbon atoms, or an acyloxy group having 1 to 10 carbon atoms which may have a substituent.

[0137] R when heterocycle B is formed 22 and R 25 and R when heterocycle C is formed. 21 and R 23 are the divalent groups -X 1 -Y 1 - and -X 2 -Y 2 -(The side that is bonded to nitrogen is X 1 and X 2 ) as X 1 and X 2 are groups represented by the following formula (1x) or (2x), and Y 1 and Y 2 are each a group selected from the following formulas (1y) to (5y): 1 and X 2 are groups represented by the following formula (2x), Y 1 and Y 2 may each be a single bond, in which case there may be an oxygen atom between the carbon atoms.

[0138] [ka]

[0139] In formula (1x), four Z's each independently represent a hydrogen atom, a hydroxyl group, an alkyl group or an alkoxy group having 1 to 6 carbon atoms, or -NR 38 R 39 (R 38 and R 39 R each independently represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms. 31 ~R 36each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an aryl group having 6 to 10 carbon atoms, R 37 represents an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 10 carbon atoms.

[0140] R 27 , R 28 , R 29 , R 31 ~R 37 , R when not forming a heterocycle 21 ~R 23 , and R 25 may be bonded to any other of these to form a 5- or 6-membered ring. 31 and R 36 , R 31 and R 37 may be directly bonded.

[0141] When no heterocycle is formed, R 21 , R 22 , R 23 and R 25 each independently represents a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group or alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 1 to 10 carbon atoms, an aryl group having 6 to 11 carbon atoms, or an aralkyl group having 7 to 18 carbon atoms which may have a substituent and which may have an oxygen atom between the carbon atoms.

[0142] In formula (I), unless otherwise specified, the hydrocarbon group is an alkyl group, an aryl group, or an aralkyl group. Unless otherwise specified, the alkyl group and the alkyl moiety in the alkoxy group, aryl group, or aralkyl group may be linear, branched, cyclic, or a combination of these structures.

[0143] The same applies to the alkyl group, alkoxy group, aryl group, and aralkyl group in the other formulae below. 29 Examples of the substituent in R include a halogen atom, a hydroxyl group, a carboxyl group, a sulfo group, a cyano group, and an acyloxy group having 1 to 6 carbon atoms. 29With the exception of the above, examples of the substituent when it is stated that "may have a substituent" include a halogen atom or an alkoxy group having 1 to 15 carbon atoms. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, with a fluorine atom and a chlorine atom being preferred.

[0144] [ka]

[0145] In the formula (II), the symbols are as follows: Ring Z is independently a 5- or 6-membered ring having 0 to 3 heteroatoms in the ring, and the hydrogen atoms of ring Z may be substituted. When the hydrogen atoms are substituted, examples of the substituent include a halogen atom or an alkyl group having 1 to 10 carbon atoms which may have a substituent.

[0146] R 1 and R 2 , R 2 and R 3 , and R 1 The carbon atoms or hetero atoms constituting ring Z may be bonded to each other to form heterocycles A1, B1, and C1 together with the nitrogen atom, respectively, and in this case, the hydrogen atoms in heterocycles A1, B1, and C1 may be substituted. When a hydrogen atom is substituted, examples of the substituent include a halogen atom or an alkyl group having 1 to 15 carbon atoms which may have a substituent.

[0147] R when not forming a heterocycle 1 and R 2 R each independently represents a hydrogen atom, a halogen atom, or a hydrocarbon group which may contain an unsaturated bond between carbon atoms, a heteroatom, or a saturated or unsaturated ring structure and which may have a substituent. 4 and R when no heterocycle is formed. 3 each independently represents a hydrogen atom, a halogen atom, or an alkyl or alkoxy group which may contain a heteroatom between carbon atoms and which may have a substituent.

[0148] In formula (II), the hydrocarbon group may have 1 to 15 carbon atoms. The alkyl group or alkoxy group may have 1 to 10 carbon atoms. In formula (II), when it says "may have a substituent", examples of the substituent include a halogen atom or an alkoxy group having 1 to 10 carbon atoms. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, with a fluorine atom and a chlorine atom being preferred.

[0149] Examples of the compound (I) include compounds represented by any one of formulas (I-1) to (I-4).

[0150] [ka]

[0151] However, the symbols in formulas (I-1) to (I-4) have the same definitions as those of the same symbols in formula (I), and the preferred embodiments are also the same.

[0152] Among the compounds (I-1) to (I-4), the NIR dye (C) is preferably the compounds (I-1) to (I-3), and particularly preferably the compound (I-1), from the viewpoint of increasing the visible light transmittance of the resin layer containing the compound.

[0153] In compound (I-1), X 1 As the group (2x), the group (2x) is preferred. 1 is preferably a single bond or a group (1y). 31 ~R 36 is preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, more preferably a hydrogen atom or a methyl group. 1 -X 1 Specific examples of - include divalent organic groups represented by formulas (11-1) to (12-3).

[0154] -C(CH3)2-CH(CH3)- …(11-1) -C(CH3)2-CH2- …(11-2) -C(CH3)2-CH(C2H5)- …(11-3) -C(CH3)2-C(CH3)(nC3H7)- …(11-4) -C(CH3)2-CH2-CH2- …(12-1) -C(CH3)2-CH2-CH(CH3)- …(12-2) -C(CH3)2-CH(CH3)-CH2- …(12-3)

[0155] In addition, in compound (I-1), R 21 are more preferably independently a group represented by formula (4-1) or formula (4-2) from the viewpoints of solubility, heat resistance, and the steepness of the change in the spectral transmittance curve near the boundary between the visible region and the near-infrared region.

[0156] [ka]

[0157] In formula (4-1) and formula (4-2), R 81 ~R 85 are independently a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms.

[0158] In compound (I-1), R 24 Ha-NR 27 R 28 -NR is preferred. 27 R 28 From the viewpoint of solubility in the resin to be combined with the NIR dye (C) and in the solvent used when forming a resin layer on a substrate, -NH-C(=O)-R 29 In compound (I-1), R 24 -NH-C(=O)-R 29 The compound is shown in formula (I-11).

[0159] [ka]

[0160] In compound (I-11), R 23 and R 26 are each independently preferably a hydrogen atom, a halogen atom, or an alkyl or alkoxy group having 1 to 6 carbon atoms, and more preferably a hydrogen atom.

[0161] In compound (I-11), R 29 As the substituent, an alkyl group having 1 to 20 carbon atoms which may have a substituent, an aryl group having 6 to 10 carbon atoms which may have a substituent, or an aralkyl group having 7 to 18 carbon atoms which may have a substituent and which may have an oxygen atom between the carbon atoms is preferred. Examples of the substituent include a halogen atom such as a fluorine atom, a hydroxyl group, a carboxyl group, a sulfo group, a cyano group, an alkyl group having 1 to 6 carbon atoms, a fluoroalkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, and an acyloxy group having 1 to 6 carbon atoms.

[0162] R 29 is preferably a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group or alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 1 to 10 carbon atoms, an aryl group having 6 to 11 carbon atoms, or an aralkyl group having 7 to 18 carbon atoms which may have a substituent and which may have an oxygen atom between the carbon atoms.

[0163] R 29 As the alkyl group, a group selected from a linear, branched or cyclic alkyl group having 1 to 17 carbon atoms which may be substituted with a fluorine atom, a phenyl group which may be substituted with a fluoroalkyl group having 1 to 6 carbon atoms and / or an alkoxy group having 1 to 6 carbon atoms, and an aralkyl group having 7 to 18 carbon atoms which may have an oxygen atom between the carbon atoms and which has a phenyl group which may be substituted with an alkyl group having 1 to 6 carbon atoms which may be substituted with a fluorine atom and / or an alkoxy group having 1 to 6 carbon atoms at the terminal.

[0164] R 29As R, a hydrocarbon group having 5 to 25 carbon atoms and at least one branch, in which one or more hydrogen atoms may be independently substituted with a halogen atom, a hydroxyl group, a carboxyl group, a sulfo group, or a cyano group, and which may contain an unsaturated bond, an oxygen atom, or a saturated or unsaturated ring structure between carbon atoms, can also be preferably used. 29 Examples of the group include groups represented by the following formulae (11a), (11b), (12a) to (12e), and (13a) to (13e).

[0165] [ka]

[0166] [ka]

[0167] More specifically, examples of compound (I-11) include the compounds shown in Table 9 below. In Table 9, the group (11-1) is represented as (11-1). The same applies to other groups. The same applies to the group representations in the other tables below. In addition, in all of the compounds shown in Table 9, the symbols on the left and right of the squarylium skeleton have the same meaning. The same applies to the squarylium dyes shown in the other tables below.

[0168] [Table 9]

[0169] In compound (I-1), R 24 From the viewpoint of increasing the transmittance of visible light, especially light with a wavelength of 430 to 550 nm, -NH-SO2-R 30 In compound (I-1), R 24 -NH-SO2-R 30 The compound is shown in formula (I-12).

[0170] [ka]

[0171] In compound (I-12), R 23 and R 26 are each independently preferably a hydrogen atom, a halogen atom, or an alkyl or alkoxy group having 1 to 6 carbon atoms, and more preferably a hydrogen atom.

[0172] In compound (I-12), R 30 From the viewpoint of light resistance, R is preferably an alkyl group or alkoxy group having 1 to 12 carbon atoms, which may be branched, or a hydrocarbon group having 6 to 16 carbon atoms and an unsaturated ring structure. Examples of the unsaturated ring structure include benzene, toluene, xylene, furan, and benzofuran. 30 are more preferably independently an alkyl group or alkoxy group having 1 to 12 carbon atoms, which may have a branch. 30 In each group represented by the formula (I-12), some or all of the hydrogen atoms may be substituted with halogen atoms, particularly fluorine atoms. The substitution of hydrogen atoms with fluorine atoms is to an extent that does not impair the adhesion between the resin layer containing the dye (I-12) and, for example, a transparent substrate.

[0173] R having an unsaturated ring structure 30 Specific examples of the alkyl group include groups represented by the following formulae (P2), (P3), (P7), (P8), and (P10) to (P13).

[0174] [ka]

[0175] More specifically, examples of compound (I-12) include the compounds shown in Table 10 below.

[0176] [Table 10]

[0177] Examples of the compound (II) include compounds represented by any one of formulas (II-1) to (II-3).

[0178] [ka]

[0179] However, in formula (II-1) and formula (II-2), R 1 and R 2 each independently represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 15 carbon atoms which may have a substituent, and R 3 ~R 6 each independently represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 10 carbon atoms which may have a substituent.

[0180] However, in formula (II-3), R 1 , R 4 , and R 9 ~R 12 each independently represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 15 carbon atoms which may have a substituent, and R 7 and R 8 each independently represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 5 carbon atoms which may have a substituent.

[0181] R in Compound (II-1) and Compound (II-2) 1 and R 2 are each independently preferably an alkyl group having 1 to 15 carbon atoms, more preferably an alkyl group having 7 to 15 carbon atoms, from the viewpoints of solubility in resin, visible light transmittance, etc., and R 1 and R 2 More preferably, at least one of R is a branched alkyl group having 7 to 15 carbon atoms, 1 and R 2 It is particularly preferable that both of the groups are alkyl groups having a branched chain and having 8 to 15 carbon atoms.

[0182] R 3From the viewpoints of solubility in resins, visible light transmittance, etc., R are preferably independently a hydrogen atom, a halogen atom, or an alkyl group having 1 to 3 carbon atoms, and more preferably a hydrogen atom, a halogen atom, or a methyl group. 4 In terms of the sharpness of the change in the region near the boundary between the visible region and the near-infrared region, R is preferably a hydrogen atom or a halogen atom, and particularly preferably a hydrogen atom. 5 and R in compound (II-2) 6 are each preferably a hydrogen atom, a halogen atom, or an alkyl group having 1 to 5 carbon atoms which may be substituted with a halogen atom, and more preferably a hydrogen atom, a halogen atom, or a methyl group.

[0183] More specifically, Compound (II-1) and Compound (II-2) include the compounds shown in Tables 11 and 12 below, respectively. In Tables 11 and 12, -CH 17 , -C4H9, -C6H 13 indicates a linear octyl group, a butyl group, and a hexyl group, respectively.

[0184] [Table 11]

[0185] [Table 12]

[0186] R in compound (II-3) 1 From the viewpoints of solubility in resin, visible light transmittance, etc., each of the groups is preferably an alkyl group having 1 to 15 carbon atoms, more preferably an alkyl group having 1 to 10 carbon atoms, and particularly preferably an ethyl group or an isopropyl group.

[0187] R 4 From the viewpoints of visible light transmittance and ease of synthesis, R is preferably a hydrogen atom or a halogen atom, and particularly preferably a hydrogen atom. 7 and R 8are each preferably a hydrogen atom, a halogen atom, or an alkyl group having 1 to 5 carbon atoms which may be substituted with a halogen atom, and more preferably a hydrogen atom, a halogen atom, or a methyl group.

[0188] R 9 ~R 12 are preferably independently a hydrogen atom, a halogen atom, or an alkyl group having 1 to 5 carbon atoms which may be substituted with a halogen atom. 9 R 10 -CR 11 R 12 Examples of - include the above groups (11-1) to (11-3) and divalent organic groups represented by the following formula (11-5). -C(CH3)(CH2-CH(CH3)2)-CH(CH3)-…(11-5)

[0189] More specifically, examples of compound (II-3) include the compounds shown in Table 13 below.

[0190] [Table 13]

[0191] Among these, dye (I-11) and dye (I-12) are preferred as the NIR dye (C) from the viewpoints of solubility in resins and solvents and visible light transmittance, and dye (I-11) shown in Table 9 and dye (I-12) shown in Table 10 are more preferred. Furthermore, among these, dye (I-11-7), dye (I-12-2), dye (I-12-9), dye (I-12-15), dye (I-12-23), dye (I-12-24), and the like are preferred.

[0192] The NIR dye (C) may consist of one compound or two or more compounds. When consisting of two or more compounds, each compound does not necessarily have the properties of the NIR dye (C), but the NIR dye (C) as a mixture may have the properties of the NIR dye (C).

[0193] Compound (I) and compound (II) can be produced by known methods. Regarding compound (I), compound (I-11) can be produced by the method described in, for example, U.S. Patent No. 5,543,086. Compound (I-12) can be produced by the method described in, for example, U.S. Patent Application Publication No. 2014 / 0061505 and WO 2014 / 088063. Compound (II) can be produced by the method described in WO 2017 / 135359.

[0194] Specific examples of the UV dye optionally contained in the absorbing layer include oxazole-based, merocyanine-based, cyanine-based, naphthalimide-based, oxadiazole-based, oxazine-based, oxazolidine-based, naphthalic acid-based, styryl-based, anthracene-based, cyclic carbonyl-based, and triazole-based dyes. Among these, oxazole-based and merocyanine-based dyes are preferred. The absorbing layer may contain one UV dye alone or two or more UV dyes in combination.

[0195] [Transparent resin (P)] The transparent resin (P) has a Tg of 130°C or higher and satisfies the above (1-1) to (1-6) in relation to the NIR dye (A). It is preferable that the transparent resin (P) further satisfies one or more of the above (1-7) to (1-9) in relation to the NIR dye (A).

[0196] Tg is determined by DSC (Differential Scanning Calorimetry). If the Tg of the transparent resin (P) is 130°C or higher, the absorbing layer has excellent heat resistance, maintaining the optical properties of the NIR dye (A) even when used at high temperatures. Furthermore, in a preferred embodiment, deformation due to heat or stress is unlikely to occur, and the filter has excellent adhesion to the dielectric multilayer film. Tg is preferably 200°C or higher, more preferably 250°C or higher. There is no particular upper limit for Tg, but from the viewpoint of moldability, etc., the Tg of the transparent resin (P) is preferably 400°C or lower.

[0197] The transparent resin (P) is not particularly limited in type as long as it has a Tg of 130°C or higher and satisfies the above requirements (1-1) to (1-6) in relation to the NIR dye (A). For example, one or more resins selected from acrylic resins, epoxy resins, enethiol resins, polycarbonate resins, polyether resins, polyarylate resins, polysulfone resins, polyethersulfone resins, polyparaphenylene resins, polyarylene ether phosphine oxide resins, polyimide resins, polyamideimide resins, polyolefin resins, cycloolefin resins, and polyester resins can be used.

[0198] Among these, at least one selected from polyimide resin, polyester resin, polycarbonate resin, cycloolefin resin and epoxy resin is preferred. From the viewpoint of adhesion to the dielectric multilayer film, polyimide resin is preferred, and polyimide resin with a Tg of 200° C. or higher is particularly preferred.

[0199] The transparent resin (P) may consist of one type of resin or two or more types of resins. When it consists of two or more types of resins, the properties of the individual resins do not necessarily need to satisfy the requirements of the transparent resin (P) as described above, but it is sufficient that the mixture as a whole satisfies the requirements of the transparent resin (P).

[0200] The transparent resin (P) may be a commercially available product, such as polyester resin OKP4HT, B-OKP-2, or OKP-850 (all of which are trade names manufactured by Osaka Gas Chemicals Co., Ltd.).

[0201] Examples of commercially available polycarbonate resins that can be used as the transparent resin (P) include FPC-0220 (trade name, manufactured by Mitsubishi Gas Chemical Company, Inc.), Panlite (registered trademark) SP3810 (trade name, manufactured by Teijin Limited), PURE-ACE (registered trademark) M5 (trade name, manufactured by Teijin Limited), and PURE-ACE S5 (trade name, manufactured by Teijin Limited).

[0202] Examples of commercially available polyimide resins that can be used as the transparent resin (P) include Neoprim (registered trademark) C-3650 (manufactured by Mitsubishi Gas Chemical Company, Inc., trade name), Neoprim C-3G30 (manufactured by Mitsubishi Gas Chemical Company, Inc., trade name), Neoprim C-3450 (manufactured by Mitsubishi Gas Chemical Company, Inc., trade name), Neoprim P500 (manufactured by Mitsubishi Gas Chemical Company, Inc., trade name), and JL-20 (manufactured by New Japan Chemical Co., Ltd., trade name) (these polyimide resin varnishes may contain silica), which are available in the form of varnish.

[0203] Examples of commercially available cycloolefin resins that can be used as the transparent resin (P) include ARTON (registered trademark) F4520 (trade name, manufactured by JSR Corporation), ZEONEX (registered trademark) K26R, F52R, T62R, and APEL (registered trademark) APL5014DP and APL6015T (all trade names, manufactured by Mitsui Chemicals, Inc.).

[0204] From the viewpoint of maintaining sufficiently high transmittance of visible light, particularly green and red light, the absorption layer is preferably composed only of the above-mentioned essential NIR dye (A), optional dyes such as NIR dye (B), NIR dye (C), and UV dye, and a transparent resin (P).

[0205] However, the absorbing layer may contain optional components such as an adhesion imparting agent, a color correction dye, a leveling agent, an antistatic agent, a heat stabilizer, a light stabilizer, an antioxidant, a dispersing agent, a flame retardant, a lubricant, and a plasticizer, as long as the effects of the present invention are not impaired.

[0206] The absorption layer has a maximum absorption wavelength λ of the NIR dye (A). max(A)TR When the average OD value in the wavelength range of ±10 nm is taken as 1, it is preferable that the following (2-1) and (2-2) be satisfied, more preferably that one or more selected from (2-3) and (2-4) be satisfied, and it is particularly preferable that all of (2-1) to (2-4) be satisfied.

[0207] (2-1) Average internal transmittance T in the wavelength range of 490 to 560 nm AVE490-560(AL) is 88% or more. AVE490-560(AL) is preferably 90% or more, and more preferably 92% or more.

[0208] (2-2) Average internal transmittance T in the wavelength range of 590 to 630 nm AVE590-630(AL) is 70% or more. AVE590-630(AL) is preferably 72% or more, more preferably 75% or more.

[0209] (2-3) Wavelength λ at which the internal transmittance is 50% in the wavelength range of 600 to 700 nm 50% The wavelength λ 50% More preferably, the wavelength is in the range of 610 to 640 nm.

[0210] (2-4) The total width of the wavelength range in the 600 to 1200 nm wavelength region where the internal transmittance is 30% or less is 250 nm or more. In the 600 to 1200 nm wavelength region, there may be one or more wavelength ranges where the internal transmittance is 30% or less. The total width of the wavelength ranges where the internal transmittance is 30% or less is preferably 250 nm or more, more preferably 300 nm or more. The larger this total width, the higher the NIR absorption ability of the absorption layer.

[0211] The content of the NIR dye (A) in the absorption layer is appropriately set so as to achieve the effects of the present filter according to the design of the present filter. The content of the NIR dye (A) in the absorption layer is preferably 1 to 15 parts by mass per 100 parts by mass of the transparent resin (P) from the viewpoint of blocking near-infrared light, particularly near-infrared light in the long wavelength range, while ensuring transmittance of visible light, particularly green and red light, and more preferably 1 to 10 parts by mass from the viewpoint of solubility.

[0212] When the absorption layer contains one or more types selected from NIR dye (A) and NIR dye (B) and NIR dye (C), the content of each NIR dye is appropriately selected according to the design of the filter so that the absorption layer satisfies the characteristics (2-1) and (2-2), and preferably so that it further satisfies one or more characteristics selected from (2-3) and (2-4).

[0213] In this case, the content of the NIR dye (A) in the absorbing layer is the same as above, and the content of one or more selected from the NIR dye (B) and the NIR dye (C) is preferably 1 to 15 parts by mass per 100 parts by mass of the transparent resin (P) for each of the NIR dye (B) and the NIR dye (C) from the viewpoint of ensuring the transmittance of visible light while exhibiting the properties of the NIR dye (B) and the NIR dye (C), and more preferably 3 to 10 parts by mass from the viewpoint of solubility. Furthermore, the total content of the NIR dye (A) and one or more selected from the NIR dye (B) and the NIR dye (C) is preferably 2 to 30 parts by mass per 100 parts by mass of the transparent resin (P), and more preferably 5 to 27 parts by mass from the viewpoint of solubility.

[0214] In the present filter, the thickness of the absorbing layer is preferably 0.1 to 100 μm. When the absorbing layer is composed of multiple layers, the total thickness of the layers is preferably 0.1 to 100 μm. If the thickness is less than 0.1 μm, the desired optical properties may not be fully exhibited, and if the thickness exceeds 100 μm, the flatness of the layer may decrease, causing in-plane variations in absorptance. The thickness of the absorbing layer is more preferably 0.3 to 50 μm. Furthermore, when other functional layers such as a reflective layer or an anti-reflection layer are provided, if the absorbing layer is too thick, cracks may occur depending on the material of the layer. Therefore, the thickness of the absorbing layer is more preferably 0.3 to 10 μm.

[0215] The absorbing layer can be formed, for example, by dissolving or dispersing NIR dye (A), preferably one or more selected from NIR dye (A), NIR dye (B), and NIR dye (C), particularly preferably NIR dye (A), NIR dye (B), and NIR dye (C), and transparent resin (P) or raw materials for transparent resin (P), and other components blended as needed, in a solvent to prepare a coating solution, which is then applied to a substrate, dried, and optionally cured. The substrate may be the transparent substrate included in the present filter, or a peelable substrate used only when forming the absorbing layer. The solvent may be a dispersion medium in which the components can be stably dispersed or dissolved.

[0216] The coating liquid may also contain a surfactant to prevent voids due to minute bubbles, depressions due to the adhesion of foreign matter, and repellency during the drying process. For example, the coating liquid can be applied by dip coating, cast coating, or spin coating. The coating liquid is applied to a substrate and then dried to form an absorbing layer. When the coating liquid contains raw materials for the transparent resin (P), it is further subjected to a curing treatment such as heat curing or photocuring.

[0217] The absorbing layer can also be produced in the form of a film by extrusion molding, and this film may be laminated to another member and integrated by thermocompression bonding, etc. For example, when the present filter includes a transparent substrate, this film may be attached to the transparent substrate.

[0218] The filter may have one or more absorbing layers. When two or more layers are present, the layers may have the same or different configurations. Furthermore, the absorbing layer may be a single layer or a laminate of multiple layers. Furthermore, the absorbing layer itself may function as a substrate (resin substrate).

[0219] (Transparent substrate) When a transparent substrate is used in the present filter, the material of the transparent substrate is not particularly limited as long as it transmits visible light of approximately 400 to 700 nm, and may be a material that absorbs near-infrared light or near-ultraviolet light, such as inorganic materials such as glass or crystal, or organic materials such as transparent resin.

[0220] Glass that can be used for transparent substrates includes absorption-type glass (near-infrared absorbing glass) containing copper ions in fluorophosphate glass or phosphate glass, soda-lime glass, borosilicate glass, alkali-free glass, quartz glass, etc. Note that "phosphate glass" also includes silicophosphate glass, in which part of the glass skeleton is composed of SiO2.

[0221] The glass may be chemically strengthened glass obtained by ion exchange at a temperature equal to or lower than the glass transition point to exchange alkali metal ions (e.g., Li ions, Na ions) having a small ionic radius present on the main surface of the glass plate with alkali ions having a larger ionic radius (e.g., Na ions or K ions for Li ions, and K ions for Na ions).

[0222] Examples of transparent resin materials that can be used as the transparent substrate include polyester resins such as polyethylene terephthalate and polybutylene terephthalate, polyolefin resins such as polyethylene, polypropylene and ethylene-vinyl acetate copolymer, acrylic resins such as norbornene resin, polyacrylate and polymethyl methacrylate, urethane resin, vinyl chloride resin, fluororesin, polycarbonate resin, polyvinyl butyral resin, polyvinyl alcohol resin, and polyimide resin.

[0223] Examples of crystalline materials that can be used for the transparent substrate include birefringent crystals such as quartz, lithium niobate, and sapphire. The optical properties of the transparent substrate should be as described above for the optical filter obtained by laminating the absorbing layer, reflective layer, etc. Sapphire is preferred as the crystalline material.

[0224] The transparent substrate is preferably made of an inorganic material, particularly glass or sapphire, from the viewpoint of shape stability related to long-term reliability of the optical characteristics and mechanical characteristics of the optical filter, and ease of handling during filter production.

[0225] The shape of the transparent substrate is not particularly limited and may be a block, plate, or film, and its thickness is, for example, preferably 0.03 to 5 mm, more preferably 0.03 to 0.5 mm from the viewpoint of thinning. From the viewpoint of processability, a transparent substrate made of glass and having a thickness of 0.05 to 0.5 mm is preferred.

[0226] (reflective layer) The reflective layer is made of a dielectric multilayer film and has the function of blocking light in a specific wavelength range. Examples of reflective layers include those that transmit visible light and have wavelength selectivity that mainly reflects light of wavelengths other than the light-blocking range of the absorbing layer. The reflective layer preferably has a reflective region that reflects near-infrared light. In this case, the reflective region of the reflective layer may include the light-blocking region of the absorbing layer in the near-infrared range. The reflective layer is not limited to the above characteristics and may be appropriately designed to further block light in a specified wavelength range, for example, the near-ultraviolet range.

[0227] When the reflective layer has a reflective region that reflects near-infrared light, the reflective layer specifically preferably satisfies the following (iii-1). (iii-1) In the spectral transmittance curve at an incident angle of 0 degrees, the average transmittance T of light with a wavelength of 850 to 1100 nm RE850-1100ave0° is less than 0.2%. Average transmittance T RE850-1100ave0° is preferably 0.15% or less, more preferably 0.05% or less.

[0228] When the reflective layer has a reflective region that reflects near-infrared light, the absorbing layer and the reflective layer preferably have the following relationship.

[0229] The wavelength λ on the short wavelength side where the transmittance of the absorption layer is 20% for light at an incident angle of 0 degrees ABSHT20-0° 650nm≦λ ABSHT20-0° When the wavelength λ satisfies ≦800 nm, ABSHT20-0° and the wavelength λ on the short wavelength side where the transmittance is 20% in the wavelength range of 650 nm or more for light at an incident angle of 0 degrees in the reflective layer. RESHT20-0° It is preferable that the relationship satisfies (iii-2). (iii-2)λ ABSHT20-0° +30nm≦λ RESHT20-0° ≦790nm

[0230] It is preferable that the reflective layer further satisfies (iii-3). (iii-3)λ RESHT20-0° From λ RESHT20-0° The average transmittance for light in the wavelength range up to +300nm is 10% or less.

[0231] The reflective layer is composed of a dielectric multilayer film in which dielectric films with low refractive index (low refractive index films) and dielectric films with high refractive index (high refractive index films) are alternately laminated. The high refractive index films preferably have a refractive index of 1.6 or more, more preferably 2.2 to 2.5. Examples of materials for the high refractive index films include Ta2O5, TiO2, and Nb2O5. Of these, TiO2 is preferred in terms of film formability, reproducibility in refractive index, etc., and stability.

[0232] On the other hand, the low refractive index film preferably has a refractive index of less than 1.6, more preferably 1.45 or more and less than 1.55. Examples of materials for the low refractive index film include SiO2, SiO x N y In terms of reproducibility, stability, economy, etc. in film formation, SiO2 is preferred.

[0233] Furthermore, it is preferable that the reflective layer exhibit a steep change in transmittance in the boundary wavelength region between the transmission region and the light blocking region. For this purpose, the total number of laminated layers in the dielectric multilayer film constituting the reflective layer is preferably 15 or more, more preferably 25 or more, and even more preferably 30 or more. However, since a large total number of laminated layers can cause warping or an increase in film thickness, the total number of laminated layers is preferably 100 or less, more preferably 75 or less, and even more preferably 60 or less. Furthermore, the thickness of the dielectric multilayer film is preferably 2 to 10 μm.

[0234] When the total number of layers and the film thickness of the dielectric multilayer film are within the above ranges, the reflective layer satisfies the requirement for miniaturization, and the incidence angle dependency can be suppressed while maintaining high productivity. In addition, the dielectric multilayer film can be formed by, for example, a vacuum film formation process such as a CVD method, a sputtering method, or a vacuum deposition method, or a wet film formation process such as a spray method or a dipping method.

[0235] The reflective layer may be one layer (one group of dielectric multilayer films) that provides predetermined optical characteristics, or two layers that provide predetermined optical characteristics. When there are two or more reflective layers, each reflective layer may have the same or different configurations. When there are two or more reflective layers, they are usually composed of multiple reflective layers with different reflection bands.

[0236] For example, when two reflective layers are provided, one may be a near-infrared reflective layer that blocks light in the short wavelength band of the near-infrared region, and the other may be a near-infrared / near-ultraviolet reflective layer that blocks light in both the long wavelength band of the near-infrared region and the near-ultraviolet region. Furthermore, for example, when the present filter has a transparent substrate and two or more reflective layers are provided, all may be provided on one main surface of the transparent substrate, or the reflective layers may be provided on both main surfaces of the transparent substrate, sandwiching the transparent substrate therebetween.

[0237] (Anti-reflection layer) Examples of antireflection layers include dielectric multilayer films, intermediate refractive index media, and moth-eye structures in which the refractive index changes gradually. Among these, dielectric multilayer films are preferred from the viewpoints of optical efficiency and productivity. Antireflection layers are obtained by alternately laminating dielectric films, similar to reflective layers.

[0238] The filter may also include other components, such as a component (layer) that provides absorption by inorganic fine particles that control the transmission and absorption of light in a specific wavelength range. Specific examples of inorganic fine particles include ITO (indium tin oxide), ATO (antimony-doped tin oxide), cesium tungstate, and lanthanum boride. ITO fine particles and cesium tungstate fine particles have high transmittance for visible light and absorb light over a wide range of infrared wavelengths exceeding 1200 nm, and therefore can be used when blocking such infrared light is required.

[0239] This filter has a reflective layer and an absorption layer containing an NIR dye (A) and a transparent resin (P), and therefore has excellent near-infrared light blocking properties, particularly long-wavelength near-infrared light blocking properties, while maintaining good transmittance of visible light, especially green and red light.

[0240] With regard to the optical properties measured at an incident angle of 0 degrees, the present filter preferably satisfies all of the following requirements (3-1) to (3-3): It is even more preferable that the present filter additionally satisfies all of the following requirements (3-4) to (3-9).

[0241] (3-1) Maximum absorption wavelength λ of NIR dye (A) max(A)TR The minimum OD value in the wavelength range of ±10 nm is 4 or more. The minimum OD value at an incident angle of 0 degrees is more preferably 5 or more.

[0242] (3-2) Average transmittance T in the wavelength range of 490 to 560 nm AVE490-560(0°) The average transmittance T is 82% or more. AVE490-560(0°) is more preferably 83.0% or more, and even more preferably 83.5% or more.

[0243] (3-3) Average transmittance T in the wavelength range of 590 to 630 nm AVE590-630(0°) is 50% or more. Average transmittance T AVE590-630(0°) is more preferably 55% or more, and even more preferably 60% or more.

[0244] (3-4) Wavelength λ at which the transmittance is 50% at an incident angle of 0 degrees in the wavelength range of 600 to 800 nm 50%(0°) and the wavelength λ at which the transmittance is 50% at an incident angle of 30 degrees 50%(30°) The absolute value of the difference between |λ 50%(30°) -λ 50%(0°) | is 5 nm or less. 50%(30°) -λ 50%(0°) is more preferably 4 nm or less, and even more preferably 3 nm or less.

[0245] (3-5) Average transmittance T in the wavelength range of 490 to 560 nm measured at an incident angle of 30 degrees AVE490-560(30°) The average transmittance T is 80% or more. AVE490-560(30°) is more preferably 81% or more, and even more preferably 83% or more.

[0246] (3-6) The maximum absorption wavelength λ of NIR dye (A) measured at an incident angle of 30 degrees max(A)TR The minimum OD value in the wavelength range of ±10 nm is 3 or more. The minimum OD value at an incident angle of 30 degrees is more preferably 4 or more.

[0247] (3-7) Wavelength λ at which the transmittance is 50% at an incident angle of 0 degrees in the wavelength range of 600 to 800 nm50%(0°) and the wavelength λ at which the transmittance is 50% at an incident angle of 50 degrees 50%(50°) The absolute value of the difference between |λ 50%(50°) -λ 50%(0°) | is 15 nm or less. 50%(50°) -λ 50%(0°) is more preferably 13 nm or less, and further preferably 10 nm or less.

[0248] (3-8) Average transmittance T in the wavelength range of 490 to 560 nm measured at an incident angle of 50 degrees AVE490-560(50°) The average transmittance T is 70% or more. AVE490-560(50°) is more preferably 72% or more, and even more preferably 74% or more.

[0249] (3-9) The maximum absorption wavelength λ of NIR dye (A) measured at an incident angle of 50 degrees max(A)TR The minimum OD value in the wavelength range of ±10 nm is 3 or more. The minimum OD value at an incident angle of 50 degrees is more preferably 4 or more.

[0250] The present filter is useful as an optical filter for an imaging device, such as a digital still camera, in equipment that includes both the imaging device and an optical component that uses laser light. The present filter is also useful for optical sensors, such as ambient light sensors.

[0251] An imaging device using this filter includes a solid-state imaging element, an imaging lens, and this filter. The filter can be used, for example, by being placed between the imaging lens and the solid-state imaging element, or by being directly attached to the solid-state imaging element, imaging lens, etc. of the imaging device via an adhesive layer. [Example]

[0252] Next, the present invention will be described in more detail with reference to examples. First, a synthesis example and characteristics of the NIR dye (A) used in the absorbing layer of the examples will be described. Next, examples of optical filters will be described.

[0253] [Test Examples 1 to 29: Synthesis and Evaluation of Dyes] (Synthesis and evaluation of pigments) NIR dye (A), NIR dye (B), and other NIR dyes were synthesized by the following methods. Synthesis Examples 1 to 11 are synthesis examples of NIR dye (A), Synthesis Examples 12 to 15 are synthesis examples of NIR dye (B), and Synthesis Examples 16 and 17 are synthesis examples of other NIR dyes. Furthermore, as the NIR dye (A), a commercially available product manufactured by Few Chemicals under the trade name S0772 and represented by the following formula (S0772) was prepared, and as the other NIR dye, a commercially available product manufactured by Few Chemicals under the trade name S2437 and represented by the following formula (S2437) was prepared.

[0254] In addition, the optical properties of these dyes were evaluated using an ultraviolet-visible-near-infrared spectrophotometer (UH4150, manufactured by Hitachi High-Tech Science Corporation), and the UH4150 was also used to evaluate the optical properties (spectral transmittance curves) described below.

[0255] [ka]

[0256] [ka]

[0257] [Synthesis Example 1] The dye (A1a-5Sb) was synthesized according to the reaction pathway shown below.

[0258] [ka]

[0259] <Step 1> Tris(4-nitrophenyl)amine (25 g, 66 mmol), palladium-activated carbon (10% palladium) (6.5 g), 1,4-dioxane (350 mL), and methanol (300 mL) were added to a 1 L recovery flask and cooled to 0 °C with stirring. Ammonium formate (65 g, 990 mmol) was added and stirred at room temperature for 4 h. After filtering the reaction mixture, the filtrate was extracted with dichloromethane, the solvent was removed, and the remaining solid was washed with 300 mL of hexane and stirred for 1 day. After removing the hexane by filtration, 18.1 g (95% yield) of intermediate 1 was obtained as a gray solid.

[0260] <Step 2> Intermediate 1 (15 g, 52 mmol) obtained in step 1, potassium carbonate (71.4 g, 520 mmol), 1-bromo-2-methylpropane (127 g, 930 mmol), and N,N-dimethylformamide (150 mL) were added to a 1 L recovery flask and stirred at 115 °C for 24 h. After returning to room temperature, the mixture was filtered and washed with dichloromethane. The filtrate was extracted with dichloromethane, and after removing the solvent, the extract was washed with methanol to obtain 18.2 g (56% yield) of a brown solid, Intermediate 2.

[0261] <Step 3> Intermediate 2 (3 g, 4.8 mmol) obtained in step 2 and N,N-dimethylformamide (60 mL) were added to a 500 mL recovery flask and stirred at 60 °C until dissolved. A solution of silver hexafluoroantimonate(V) (3.79 g, 11 mmol) dissolved in N,N-dimethylformamide (30 mL) was then added to the solution containing Intermediate 2 and stirred at 60 °C for 3 h. The precipitated solid was filtered, and the recovered solid was isolated by column chromatography (dichloromethane:methanol = 1000:30). After removing the solvent, the solid was dissolved in a small amount of dichloromethane and reprecipitated with ethyl acetate to obtain 2.8 g (54% yield) of the green dye (A1a-5Sb).

[0262] [Synthesis Example 2] Intermediate 2 (3 g, 4.8 mmol) obtained in Step 2 of Synthesis Example 1 and ethyl acetate (50 mL) were added to a 500 mL recovery flask and stirred at 60 °C until dissolved. A solution of potassium bis(trifluoromethylsulfonyl)imide (3.8 g, 12 mmol) and ammonium peroxodisulfate (2.7 g, 12 mmol) dissolved in a mixed solvent of acetonitrile (30 mL) and water (30 mL) was added to the solution containing Intermediate 2 and stirred at 60 °C for 4 h. After the reaction was completed, the mixture was returned to room temperature, and water (100 mL) and hexane (200 mL) were added to precipitate a solid, which was then filtered and washed with ethyl acetate. The recovered solid was isolated by column chromatography (dichloromethane:methanol = 1000:30). After removing the solvent, the solid was dissolved in a small amount of dichloromethane and reprecipitated with ethyl acetate to obtain 3.6 g (63% yield) of the dye (A1a-5NS) as a green solid.

[0263] [Synthesis Example 3] A green solid dye (A1a-5P) (2.6 g, yield 59%) was obtained in the same manner as in Synthesis Example 2, except that potassium bis(trifluoromethylsulfonyl)imide was replaced with potassium hexafluorophosphate (2.2 g, 12 mmol).

[0264] [Synthesis Example 4] A green solid dye (A1a-5Cl) (2.5 g, 63% yield) was obtained in the same manner as in Synthesis Example 2, except that potassium bis(trifluoromethylsulfonyl)imide was replaced with sodium perchlorate (1.5 g, 12 mmol).

[0265] [Synthesis Example 5] A green solid dye (A1a-5B) (2.7 g, yield 71%) was obtained in the same manner as in Synthesis Example 2, except that potassium bis(trifluoromethylsulfonyl)imide was replaced with sodium tetrafluoroborate (1.3 g, 12 mmol).

[0266] [Synthesis Example 6] The dye (A1a-4P) was synthesized according to the reaction pathway shown below.

[0267] [ka]

[0268] <Step 1> The same raw materials were used in Step 2 of Synthesis Example 1, except that 1-bromo-2-methylpropane was replaced with 1-bromobutane (127 g, 930 mmol), and the reaction was carried out using the same starting materials. After extraction with dichloromethane, the product was isolated by column chromatography (hexane:ethyl acetate=1000:40) to obtain 23 g (yield 71%) of Intermediate 3, a pale yellow oily substance.

[0269] <Step 2> Intermediate 3 (3 g, 4.8 mmol) obtained in Step 1 of Synthesis Example 6 and ethyl acetate (50 mL) were added to a 500 mL recovery flask and stirred at 60 °C until dissolved. A solution of potassium hexafluorophosphate (2.2 g, 12 mmol) and ammonium peroxodisulfate (2.7 g, 12 mmol) dissolved in a mixed solvent of acetonitrile (30 mL) and water (30 mL) was then added to the solution containing Intermediate 3 and stirred at 60 °C for 4 h. After the reaction was completed, the mixture was returned to room temperature, and water (100 mL) and hexane (200 mL) were added to precipitate a solid, which was then filtered and washed with ethyl acetate. The recovered solid was isolated by column chromatography (dichloromethane:ethyl acetate = 10:1). After removing the solvent, the solid was dissolved in a small amount of dichloromethane and reprecipitated using hexane to obtain 2.8 g (63% yield) of the dye (A1a-4P) as a green solid.

[0270] [Synthesis Example 7] A green solid dye (A1a-4NS) (3.1 g, 54% yield) was obtained in the same manner as in Step 2 of Synthesis Example 6, except that potassium hexafluorophosphate was replaced with potassium bis(trifluoromethylsulfonyl)imide (3.8 g, 12 mmol).

[0271] [Synthesis Example 8] 0.9 g (yield 22%) of dye (A1a-4B) was obtained as a green solid in the same manner as in Step 2 of Synthesis Example 6, except that potassium hexafluorophosphate was changed to sodium tetrafluoroborate (1.3 g, 12 mmol).

[0272] [Synthesis Example 9] The dye (A1a-7P) was synthesized according to the method shown below.

[0273] <Step 1> The reaction was carried out using the same raw materials as in Step 2 of Synthesis Example 1, except that the 1-bromo-2-methylpropane used in Step 2 was replaced with 1-bromooctane (18 equivalents relative to Intermediate 1). After extraction with dichloromethane, the product was isolated by column chromatography (hexane:ethyl acetate=1000:40) to obtain 13.4 g (yield 67%) of Intermediate 4, a pale yellow oily substance.

[0274] <Step 2> In the same manner as described in Step 2 of Synthesis Example 6, except that Intermediate 3 was changed to Intermediate 4, 1.0 g (yield 20%) of a green solid dye (A1a-7P) was obtained.

[0275] [Synthesis Example 10] In a similar manner to Synthesis Example 9, except that the potassium hexafluorophosphate used in Step 2 was changed to potassium bis(trifluoromethylsulfonyl)imide, 2.4 g (yield 37%) of a green solid dye (A1a-7NS) was obtained.

[0276] [Synthesis Example 11] The dye (A1a-1NS) was synthesized according to the method shown below.

[0277] <Step 1> The same raw materials were used in Step 2 of Synthesis Example 1 except that 1-bromo-2-methylpropane was replaced with bromoethane (18 equivalents relative to Intermediate 1), and the reaction was carried out using the same starting materials. After extraction with dichloromethane, the product was isolated by column chromatography (hexane:ethyl acetate=8:2), yielding 1.7 g (yield 12%) of Intermediate 5, a pale yellow oily substance.

[0278] <Step 2> In a similar manner to that described in Step 2 of Synthesis Example 6, except that Intermediate 3 was changed to Intermediate 5 and potassium hexafluorophosphate was changed to potassium bis(trifluoromethylsulfonyl)imide, 0.8 g (yield 22%) of a green solid dye (A1a-1NS) was obtained.

[0279] [Synthesis Example 12] The dye (B1-5Sb) was synthesized according to the reaction pathway shown below.

[0280] [ka]

[0281] <Step 1> 4-Bromoaniline (25.4 g, 148 mmol) and N,N-dimethylformamide (80 mL) were added to a 1 L recovery flask and stirred at 110 °C until dissolved. 1-Bromo-2-methylpropane (54.7 g, 399 mmol) and N-ethyldiisopropylamine (57.3 g, 444 mmol) were then added and reacted at 130 °C for 15 h. After returning to room temperature, extraction was performed with a mixed solvent of ethyl acetate and hexane (1:4). After removing the solvent, isolation was performed by column chromatography (hexane:ethyl acetate = 1000:50) to obtain 15 g (36% yield) of intermediate 6 as a white solid.

[0282] <Step 2> Intermediate 6 (12 g, 42 mmol) obtained in step 1, 1,4-phenylenediamine (1.1 g, 9.8 mmol), sodium tert-butoxide (8 g, 83 mmol), tris(dibenzylideneacetone)dipalladium(0) (1 g, 1.1 mmol), 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl (2 g, 4 mmol), and 1,4-dioxane (80 mL) were added to a 1 L recovery flask and reacted at 100 °C for 20 h. After returning to room temperature and removing the remaining catalyst solids by filtration through Celite, extraction was performed with dichloromethane and saturated aqueous ammonium chloride. After removing the solvent, the precipitated solid was washed with methanol to obtain 17.5 g (97% yield) of a brown solid, intermediate 7.

[0283] <Step 3> Intermediate 7 (2 g, 2 mmol) obtained in step 2 and N,N-dimethylformamide (20 mL) were added to a 500 mL recovery flask and stirred at 60 °C until dissolved. A solution of silver hexafluoroantimonate(V) (1.6 g, 4.5 mmol) dissolved in N,N-dimethylformamide (20 mL) was then added to the solution containing Intermediate 7 and stirred at 60 °C for 2 h. The precipitated solid was filtered and washed with N,N-dimethylformamide. Approximately 150 mL of water was slowly added dropwise to the filtrate. The precipitated solid was filtered again, washed with water and hexane, and isolated by column chromatography (dichloromethane:ethyl acetate = 7:3). After removing the solvent, the solid was dissolved in a small amount of dichloromethane and reprecipitated with ethyl acetate to obtain 1.3 g (43% yield) of the dye (B1-5Sb) as a reddish-brown solid.

[0284] [Synthesis Example 13] Intermediate 7 (5 g, 5.4 mmol) obtained in Step 2 of Synthesis Example 12 and ethyl acetate (50 mL) were added to a 500 mL recovery flask and stirred at 60 °C until dissolved. A solution of potassium bis(trifluoromethylsulfonyl)imide (4.4 g, 13.8 mmol) and ammonium peroxodisulfate (3.1 g, 13.5 mmol) dissolved in a mixed solvent of acetonitrile (30 mL) and water (30 mL) was then added to the solution containing Intermediate 7, and the mixture was stirred at 60 °C for 4 h. After the reaction was complete, the mixture was returned to room temperature, and water (100 mL) and hexane (200 mL) were added to precipitate a solid, which was then filtered and washed with ethyl acetate. The recovered solid was isolated by column chromatography (dichloromethane:methanol = 1000:30). After removing the solvent, the solid was dissolved in a small amount of dichloromethane and reprecipitated using hexane to obtain 6.0 g (yield 75%) of a reddish-brown solid pigment (B1-5NS).

[0285] [Synthesis Example 14] A reddish-brown solid dye (B1-5P) was obtained in a yield of 36% in the same manner as in Synthesis Example 2, except that potassium bis(trifluoromethylsulfonyl)imide was replaced with potassium hexafluorophosphate.

[0286] [Synthesis Example 15] An n-butyl-modified intermediate was synthesized (yield 89%) in the same manner as in Step 1 of Synthesis Example 12, except that 1-bromo-2-methylpropane was replaced with 1-bromobutane (54.7 g, 399 mmol). Using the same method as in Steps 2 and 3 of Synthesis Example 12, a reddish-brown solid dye (B1-4Sb) was obtained in a yield of 72%.

[0287] [Synthesis Example 16] Dye (S1) was synthesized according to the reaction pathway shown below. Specifically, product (10) (6.5 mmol), prepared with reference to European Journal of Medical Chemistry, 54, 647, (2012), and squaric acid (3.4 mmol) were placed in a 500 mL recovery flask, dissolved in toluene (330 mL) and 1-butanol (110 mL), and quinoline (8 mmol) was added. The mixture was stirred at 150 °C for 4 hours. Product (10) is the iodine salt of a compound in which the hydrogen at the 1-position of 2-methyl-benzo[c,d]indole is substituted with R, where R is -CH2-CH(CH 13 )(C8H 17 )

[0288] After the reaction was completed, the solvent was removed, and the product was isolated by column chromatography (hexane:ethyl acetate=8:2). After the solvent was removed and the product was washed with hexane, a reddish-brown solid dye (S1) (0.5 g, yield 25%) was obtained.

[0289] [ka]

[0290] [Synthesis Example 16] Dye (S2) was synthesized according to the reaction pathway shown below.

[0291] [ka]

[0292] <Step 1> A 1-L three-neck flask was charged with benzo[cd]indol-2(1H)-one (30 g, 177 mmol) and chloroform (500 mL). The mixture was heated to 65 °C with stirring to dissolve the raw materials, then cooled to 0 °C and bromine (28.3 g, 177 mmol) was slowly added dropwise. After the addition was complete, the mixture was returned to room temperature and stirred for 24 h. Hexane was then added to the reaction mixture to dilute the mixture, and the precipitate was collected by filtration. The solid on the filter paper was washed multiple times with hexane and dried in vacuo to obtain 60 g of intermediate 8, an ochre solid (yield: over 100%).

[0293] <Step 2> Intermediate 8 (30 g, 121 mmol) synthesized in Step 1, 4-dimethylaminopyridine (2.0 g, 16 mmol), potassium iodide (4.0 g, 24 mmol), and sulfolane (300 mL) were added to a 1 L recovery flask and stirred at 70 °C for 1 h. Potassium hydroxide (21 g, 374 mmol) and 7-(Bromomethyl)pentadecane (111 g, 363 mmol) were added to the reaction mixture and reacted at 70 °C for 19 h. After the reaction was completed, the mixture was returned to room temperature and extracted with a 4:1 mixture of hexane and ethyl acetate and water to remove the solvent. The product was then isolated by column chromatography (hexane:ethyl acetate = 1000:10) to obtain 45 g (78% yield) of intermediate 9 as a yellow oil.

[0294] <Step 3> Intermediate 9 (33 g, 70 mmol) synthesized in Step 2, ethyl acetate (2.5 g, 28 mmol), copper(I) iodide (1.9 g, 10 mmol), and 28% sodium methoxide / methanol solution (42 g) were added to a 1 L recovery flask and stirred at 90 °C for 6 h. Copper(I) iodide (1 g, 5 mmol) and 28% sodium methoxide / methanol solution (20 g) were then added and stirred at 90 °C for an additional 15 h. After the reaction was complete, the mixture was returned to room temperature, filtered through Celite, and extracted with dichloromethane and water to remove the solvent. The product was then isolated by column chromatography (hexane:ethyl acetate = 1000:30) to obtain 26 g (88% yield) of intermediate 10 as a yellow oil.

[0295] <Step 4> Intermediate 10 (26 g, 61 mmol) synthesized in Step 3 and dichloromethane (500 mL) were placed in a 2 L three-neck flask and cooled to -78 °C. Then, 1 M boron tribromide dichloromethane solution (200 mL) was slowly added dropwise. After the addition was complete, the reaction solution was returned to room temperature and stirred for 2 h. After the reaction was complete, the mixture was cooled to 0 °C and 200 mL of water was slowly added to quench the boron tribromide. The precipitated solid was filtered, and the filtrate was extracted with dichloromethane and aqueous sodium bicarbonate solution to remove the solvent. The solid recovered during filtration was combined with the intermediate 10 and washed multiple times with hexane to obtain 24 g (95% yield) of a yellow solid, intermediate 11.

[0296] <Step 5> Intermediate 11 (10 g, 24 mmol) synthesized in Step 4, potassium carbonate (16.9 g, 120 mmol), and DMF (120 mL) were added to a 1 L three-neck flask and stirred at 70 °C. 7-(Bromomethyl)pentadecane (8.95 g, 29 mmol) was then added dropwise and stirred at 70 °C for 2 h. After the reaction was completed, the product was extracted with an organic solvent (hexane:ethyl acetate = 1:1) and water, and the solvent was removed. The product was then isolated by column chromatography (hexane:ethyl acetate = 10:1) to obtain 14 g (91% yield) of intermediate 12, a yellow oily substance.

[0297] <Step 6> Intermediate 12 (14 g, 22 mmol), epichlorohydrin (8.2 g, 88 mmol), chloroform (50 mL), and diethyl ether (20 mL) were added to a 1 L three-neck flask and stirred at 70 °C. A mixed solution of boron trifluoride-ethyl ether complex (15.9 g, 110 mmol) and chloroform (30 mL) was added dropwise, and the mixture was heated to 130 °C and stirred for 15 h. The reaction solution was then cooled, toluene was added, and the solvent was removed twice using an evaporator to obtain an orange-brown oil (Intermediate 13'). Ethanol (20 mL), Meldrum's acid (4.6 g, 32 mmol), and triethylamine (11.4 g, 110 mmol) were added to the oil, and the mixture was stirred at room temperature for 5 h. After the reaction was completed, toluene was added, and the solvent was removed twice using an evaporator. The residue was then isolated by column chromatography (hexane:ethyl acetate=6:4) to obtain 8 g (yield 47%) of intermediate 13, a magenta oily substance.

[0298] <Step 7> Intermediate 13 (8 g, 10 mmol) synthesized in step 6 and hydrochloric acid (15 mL) were added to a 1 L recovery flask and heated at 130 °C for 1 hour. Tetrafluoroboric acid (3 mL) was then added and the reaction was continued for another 1 hour. After the reaction was completed, the mixture was returned to room temperature, 50 mL of water was added, and 20 mL of tetrafluoroboric acid was added. After that, an extraction operation was performed using dichloromethane and water, and the solvent was removed, yielding 7.1 g (94% yield) of intermediate 14, an orange oily substance.

[0299] <Step 8> Intermediate 14 (7.1 g, 10 mmol) synthesized in step 7, squaric acid (0.59 g, 5.2 mmol), toluene (500 mL), 1-butanol (170 mL), and quinoline (1.77 g) were added to a 1 L recovery flask and reacted at 130 °C for 2 hours. After that, the solvent was removed using an evaporator, and the product was isolated by column chromatography (hexane:ethyl acetate = 9:1), yielding 3.4 g (55% yield) of dye (S2) as a black solid.

[0300] Dye-containing resin layers were fabricated using the various dyes and transparent resins prepared above, and their optical properties were measured. Furthermore, various dyes were dissolved in dichloromethane, and their optical properties were measured and compared with those of the dye-containing resin layer. The following commercially available transparent resins were used. The results are shown in Table 14.

[0301] (Transparent resin (P)) Resin A: Neoprim (registered trademark) C-3G30 (trade name, manufactured by Mitsubishi Gas Chemical Company, Inc.), varnish containing polyimide resin, Tg of the contained polyimide resin: 320°C Resin B: ARTON (registered trademark) F4520 (trade name, manufactured by JSR Corporation), cycloolefin resin, Tg: 151°C Resin C: B-OKP-2 (trade name, manufactured by Osaka Gas Chemicals Co., Ltd.), polyester resin, Tg: 150°C Resin D: OKP-850 (trade name, manufactured by Osaka Gas Chemicals Co., Ltd.), polyester resin, Tg: 151°C Resin E: Panlite (registered trademark) SP3810 (trade name, manufactured by Teijin Limited), polycarbonate resin, Tg: 150°C (Other transparent resins) Resin F: BR50 (trade name, manufactured by Mitsubishi Rayon Co., Ltd.), acrylic resin, Tg: 100°C

[0302] The dye prepared above was uniformly dissolved in a transparent resin dissolved in cyclohexanone at a concentration of 10% by mass relative to the solid content of the transparent resin. The resulting solution was applied to a glass plate (D263: SCHOTT, trade name) and dried to obtain a dye-containing resin layer with a thickness of approximately 1 μm. The spectral transmittance curve of the dye-containing resin layer was obtained using the spectral transmittance curve of the glass plate with the dye-containing resin layer and the spectral transmittance curve of the glass plate.

[0303] The internal transmittance spectrum of the prepared dye-containing resin layer was measured using an ultraviolet-visible-near-infrared spectrophotometer over a wavelength range of 350 to 1200 nm, and calculated using the internal transmittance T [%] (= measured transmittance [%] / (100-measured reflectance [%]) × 100 [%]). The amount of dye added (dye concentration) shown in the table is the maximum absorption wavelength λ at a film thickness of 2 μm. maxTRThe parts by mass are relative to 100 parts by mass of transparent resin when the internal light transmittance is adjusted to 10%.

[0304] Maximum absorption wavelength λ maxTR From the spectral transmittance curve adjusted so that the transmittance of light at 435 to 480 nm is 10%, the average internal transmittance T AVE435-480TR , the average internal transmittance T of light with wavelengths of 490 to 560 nm AVE490-560TR , the average internal transmittance T of light with wavelengths of 590 to 630 nm AVE590-630TR When there are two wavelengths in the wavelength region of 650 to 1150 nm at which the internal transmittance is 50%, the width W between the two wavelengths is T50% In the table, the wavelength on the short wavelength side where the internal transmittance is 50% in the wavelength range of 650 to 1150 nm is λ SH50% , the wavelength on the long wavelength side is λ LG50% As shown.

[0305] Dissolve it in dichloromethane and measure the light absorption spectrum at wavelengths of 350 to 1200 nm. From the spectral transmittance curve, determine the maximum absorption wavelength λ maxDCM Furthermore, the dye concentration in dichloromethane was calculated based on the maximum absorption wavelength λ maxDCM From the spectral transmittance curve adjusted so that the transmittance of light at wavelengths of 435 to 480 nm is 10%, the average transmittance T AVE435-480DCM , the average transmittance T of light with wavelengths of 490 to 560 nm AVE490-560DCM , the average transmittance T of light with wavelengths of 590 to 630 nm AVE590-630DCM The difference between the average internal transmittance of the dye-containing resin layer and the average internal transmittance of the dye-containing resin layer was calculated. AVE435-480 In the "Difference" column, AVE435-480DCM -T AVE435-480TR Similarly, "T AVE490-560 In the "Difference" column, AVE490-560DCM -T AVE490-560TR "T AVE590-630 In the "Difference" column, AVE590-630DCM -T AVE590-630TR showed.

[0306] [Table 14]

[0307] FIG. 7 shows the spectral transmittance curves of the dye (A1a-5NS) in a transparent resin (P; resin A) and in dichloromethane in Test Example 2. FIG. 8 shows the spectral transmittance curves of the dye (A1a-5NS) in a transparent resin (resin F) and in dichloromethane in Test Example 19. In FIGS. 7 and 9, the spectral transmittance curves of the dye measured in the transparent resin are marked with double arrows. T50% The range of

[0308] From Table 14, it can be seen that the combinations of NIR dye (A) and transparent resin (P) in Test Examples 1 to 18 have the properties (1-1) to (1-6). T50% It can be seen that the tris-type immonium dye is preferable in that it has a wide range of absorption of near-infrared light, as shown by Xa. In addition, the NIR dye (A) is preferable in that it has a small difference in optical properties between in a dichloromethane solution and in a resin, as shown by Xa. - N[SO2CF3]2 - , SbF6 - or PF6 - is preferred, and N[SO2CF3]2 - It can be seen that the transparent resin (P) is preferably a polyimide resin because it can increase the visible light transmittance.

[0309] In Test Examples 19 to 23, either the NIR dye or the transparent resin did not satisfy the requirements for the NIR dye (A) or the transparent resin (P), and therefore one or more of the properties (1-1) to (1-6) were not satisfied. Test Examples 24 to 28 are examples in which the dye (B1) was combined with a transparent resin (P) or a transparent resin that did not satisfy the requirements for the transparent resin (P), and it was found that the dye (B1) functions favorably as the NIR dye (B) when combined with a transparent resin (P) such as a polyimide resin.

[0310] [Examples 1 to 11: Manufacturing and evaluation of optical filters] (Optical filter manufacturing) Optical filters having the same configuration as optical filter 10B shown in Fig. 2 were manufactured and evaluated by the following method. The configurations and evaluation results of the optical filters are shown in Table 15. Examples 1 to 7 are working examples, and Examples 8 to 11 are comparative examples.

[0311] In each example, a CuO-containing fluorophosphate glass substrate (manufactured by AGC Corporation, thickness 0.2 mm) or a 0.08 mm thick Teijin PureAce WRM5-80 resin substrate (manufactured by Teijin Limited, trade name, polycarbonate resin, Tg 215°C) was used as the transparent substrate. In the table, these are referred to as "absorbing glass" and "PC resin," respectively.

[0312] The reflective layer used was a dielectric multilayer film formed as follows. The dielectric multilayer film was formed by depositing a total of 42 alternating layers of TiO2 and SiO2 films using a vapor deposition method on one main surface of a transparent substrate. The configuration of the reflective layer was simulated using the number of layers in the dielectric multilayer film, the thickness of the TiO2 film, and the thickness of the SiO2 film as parameters, and was designed to have an average transmittance of 0.03% for light with wavelengths from 850 to 1100 nm on the spectral transmittance curve at an incident angle of 0 degrees.

[0313] In addition, on the main surface of the transparent substrate opposite to the surface on which the reflective layer was formed, an absorption layer approximately 2.0 μm thick was formed by combining the transparent resin shown in the table with NIR dye (A), NIR dye (B), NIR dye (C) (dye (I-12-23)), and other NIR dyes. Here, for dye (I-12-23), the maximum absorption wavelength λ in the spectral transmittance curve for wavelengths of 350 to 1200 nm measured after being incorporated into resin A was max(C)TR is 714 nm. The content of the pigment in the table is the parts by mass of the pigment relative to 100 parts by mass of the transparent resin.

[0314] The following dyes (15), (16), and (17) were used as other NIR dyes. Here, dye (15) has a maximum absorption wavelength λ in the spectral transmittance curve of 350 to 1200 nm when incorporated into resin A and measured. max(A)TRThe maximum absorption wavelength λ of the dye (16) and dye (17) in the spectral transmittance curve for the wavelength range of 350 to 1200 nm measured after being incorporated into resin F is 937 nm, but these dyes do not satisfy the characteristic (1-4). maxTR are 839 nm and 771 nm, respectively.

[0315] [Synthesis of dye (15)] The dye (15) was synthesized according to the reaction scheme shown below.

[0316] [ka]

[0317] <Step b1> 2-Bromothiophene (9.00 g, 55.2 mmol) and magnesium (4.03 g, 165 mmol) were placed in a flask and dissolved in anhydrous tetrahydrofuran (55 mL) under a nitrogen atmosphere. The mixture was stirred at 80°C for 1 hour. [1,3-bis(diphenylphosphino)propane]nickel(II) dichloride (1.20 g, 2.21 mmol) and 2,3-dibromothiophene (12.7 g, 52.5 mmol) were placed in a separate flask and dissolved in anhydrous diethyl ether (110 mL). The diethyl ether mixture was cooled to 0°C, and the tetrahydrofuran mixture was added dropwise. The mixture was stirred at room temperature for 3 hours. After the reaction was completed, water (55 mL) was added to the mixture, which was then extracted with ethyl acetate. The organic layer was washed with saturated brine, the solvent was removed, and intermediate A3-11 (8.93 g, 66% yield) was obtained by column chromatography (hexane).

[0318] <Step b2> Intermediate A3-11 (8.09 g, 33 mmol) obtained in step b1 was placed in a flask and dissolved in anhydrous diethyl ether (230 mL) under a nitrogen atmosphere. The solution was cooled to -78 °C, and a 1.6 M solution of n-butyllithium in hexane (20 mL, 32.0 mmol) was added dropwise and stirred for 1 hour. Subsequently, a solution of benzophenone (6.56 g, 36.0 mmol) in anhydrous diethyl ether (120 mL) was added dropwise. The mixture was stirred at room temperature for 24 hours. After the reaction was completed, saturated aqueous ammonium chloride solution (200 mL) was added, and the mixture was extracted with diisopropyl ether. The resulting organic layer was washed with saturated brine, the solvent was removed, and intermediate A3-12 (8.81 g, 77% yield) was obtained by column chromatography (hexane:dichloromethane = 1:1).

[0319] <Step b3> Intermediate A3-12 (4.94 g, 14.4 mmol) obtained in step b2 and Amberlyst 15 (2.30 g) were placed in a flask and dissolved in anhydrous toluene (300 mL) under a nitrogen atmosphere. The mixture was refluxed and stirred for 7 hours. After the reaction was completed, the filtrate was filtered, the solvent was removed, and intermediate A3-13 (4.29 g, 91%) was obtained by column chromatography (hexane:dichloromethane = 2:1).

[0320] <Step b4> Intermediate A3-13 (4.00 g, 12.1 mmol) obtained in step b3 was placed in a flask and dissolved in anhydrous dimethylformamide (120 mL) under a nitrogen atmosphere. A solution of N-bromosuccinimide (2.16 g, 12.1 mmol) in anhydrous dimethylformamide (30 mL) was added dropwise to the solution. The mixture was stirred at room temperature for 24 hours. After the reaction was completed, the mixture was poured into ice water and extracted with diisopropyl ether. The resulting organic layer was washed with saturated brine, and the solvent was removed. Intermediate A3-14 (3.67 g, 74% yield) was obtained by column chromatography (dichloromethane).

[0321] <Step b5> A flask was charged with the intermediate A3-14 (3.50 g, 8.55 mmol) obtained in step b4 and magnesium turnings (0.416 g, 17.1 mmol) and dissolved in anhydrous tetrahydrofuran (20 mL) under a nitrogen atmosphere. The solution was refluxed for 3 hours and cooled to -40 °C. In a separate flask, N-chlorosuccinimide (1.03 g, 7.70 mmol) was dissolved in anhydrous toluene (20 mL) under a nitrogen atmosphere, and bis-(2-ethylhexyl)amine (1.86 g, 7.70 mmol) was added and stirred for 20 minutes.

[0322] Tetraisopropyl orthotitanate (2.43 g, 8.55 mmol) was added dropwise to the mixed solution cooled to -40°C and stirred for 5 minutes, followed by the dropwise addition of a mixed solution of N-chlorosuccinimide and bis-(2-ethylhexyl)amine. The mixture was stirred at room temperature for 3 hours, and upon completion of the reaction, saturated aqueous potassium carbonate solution (17 ml) was added. The mixture was then diluted with ethyl acetate and filtered, and the resulting solution was extracted with ethyl acetate. The resulting organic layer was washed with saturated brine, the solvent was removed, and intermediate A3-15 (1.34 g, 27.5% yield) was obtained by column chromatography (hexane:triethylamine=100:3).

[0323] <Step b6> Intermediate A3-15 (1.30 g, 2.28 mmol) obtained in step b5 and 3,4-dihydroxy-3-cyclobutene-1,2-dione (0.130 g, 1.14 mmol) were placed in a flask and dissolved in a mixture of n-butanol (6 mL) and toluene (6 mL) under a nitrogen atmosphere. The mixture was refluxed and stirred for 3 hours. After the reaction was completed, the solvent was removed and the dye (15) (0.445 g, 32% yield) was obtained by column chromatography (dichloromethane:methanol:triethylamine = 100:1:3).

[0324] [Synthesis of dye (16) and dye (17)] Dyes (16) and (17) were synthesized according to the method described in J. Heterocyclic. Chem., 42, 959, (2005).

[0325] [ka]

[0326] [ka]

[0327] (evaluation) <Optical properties of the absorption layer> The spectral transmittance curves were determined for the absorption layers of the optical filters of Examples 1 to 11. The maximum absorption wavelength λ of the NIR dye (A) was max(A)TR The average internal transmittance T in the wavelength range of 435 to 480 nm when the average OD value in the wavelength range of ±10 nm is set to 1. AVE435-480(AL) , the average internal transmittance T in the wavelength range of 490 to 560 nm AVE490-560(AL) , the average internal transmittance T in the wavelength range of 590 to 630 nm AVE590-630(AL) asked for.

[0328] Furthermore, the maximum absorption wavelength λ of the NIR dye (A) max(A)TR The wavelength λ at which the internal transmittance is 50% in the wavelength range of 600 to 800 nm when the average OD value is 1 in the wavelength range of ±10 nm. 50% The total width of the wavelength range in which the internal transmittance is 30% or less in the wavelength range of 600 to 1200 nm ("T 30% The table also shows the transmittance T 500 , and transmittance T at a wavelength of 600 nm 600 showed.

[0329] <Optical characteristics of optical filters> Furthermore, the spectral transmittance curves of the obtained optical filters of Examples 1 to 11 were obtained at angles of incidence of 0 degrees, 30 degrees, and 50 degrees, and the following optical properties were determined.

[0330] Maximum absorption wavelength λ of NIR dye (A) at an incident angle of 0 degrees max(A)TR Minimum OD value in the wavelength range of ±10 nm, average transmittance T in the wavelength range of 435 to 480 nmAVE435-480(0°) , average transmittance T in the wavelength range of 490 to 560 nm AVE490-560(0°) , average transmittance T in the wavelength range of 590 to 630 nm AVE590-630(0°) , the wavelength λ at which the transmittance becomes 50% in the wavelength range of 600 to 800 nm 50%(0°) asked for.

[0331] Maximum absorption wavelength λ of NIR dye (A) at an incident angle of 30 degrees max(A)TR Minimum OD value in the wavelength range of ±10 nm, wavelength λ at which transmittance is 50% at an incident angle of 0 degrees in the wavelength range of 600 to 800 nm 50%(0°) and the wavelength λ at which the transmittance is 50% at an incident angle of 30 degrees 50%(30°) The absolute value of the difference between |λ 50%(30°) -λ 50%(0°) |, average transmittance T in the wavelength range of 490 to 560 nm AVE490-560(30°) asked for.

[0332] Maximum absorption wavelength λ of NIR dye (A) at an incident angle of 50 degrees max(A)TR Minimum OD value in the wavelength range of ±10 nm, wavelength λ at which transmittance is 50% at an incident angle of 0 degrees in the wavelength range of 600 to 800 nm 50%(0°) and the wavelength λ at which the transmittance is 50% at an incident angle of 50 degrees 50%(50°) The absolute value of the difference between |λ 50%(50°) -λ 50%(0°) |, average transmittance T in the wavelength range of 490 to 560 nm AVE490-560(50°) asked for.

[0333] [Table 15]

[0334] 9 and 10 show the spectral transmittance curves of the absorption layer and the optical filter in the optical filter of each example, for Example 1, for Example 4, and for Example 6, respectively. FIGS. 15 and 16 show the spectral transmittance curves of the absorption layer and the optical filter in the optical filter of Example 8, which is a comparative example. In the diagrams of the spectral transmittance curves of the absorption layer of each example, "T 30%The width below is indicated by W or Wa and Wb. In examples 4, 6, and 8, "T 30% The "width below" is the sum of Wa and Wb.

[0335] 10, 12, and 14, it can be seen that the optical filters of Examples 1 to 7 can maintain sufficiently high transmittance for visible light, particularly for green and red light, and also have excellent near-infrared light blocking properties, particularly for long-wavelength near-infrared light.

[0336] Although the present invention has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the present invention. This application is based on a Japanese patent application (Patent Application No. 2019-114575) filed on June 20, 2019, the contents of which are incorporated herein by reference. [Industrial Applicability]

[0337] The optical filter of the present invention can maintain a sufficiently high transmittance for visible light, particularly for green and red light, and has excellent near-infrared light blocking properties, particularly for long-wavelength near-infrared light. According to the present invention, an imaging device and an optical sensor that use the optical filter and have excellent color reproducibility and durability can be provided. [Explanation of symbols]

[0338] 10A, 10B, 10C, 10D, 10E, 10F...optical filters, 11, 11a, 11b...absorption layers, 12, 12a, 12b...reflective layers, 13...transparent substrate, 14...anti-reflection layer.

Claims

1. An optical filter comprising an absorption layer containing a transparent resin, a near-infrared absorbing dye (A) having a maximum absorption wavelength in a wavelength region of 850 to 1100 nm, and a near-infrared absorbing dye (C) having a maximum absorption wavelength in a wavelength region of 630 to 750 nm, and a dielectric multilayer film, An optical filter that satisfies all of the following requirements (3-2) to (3-8). (3-2) In the optical characteristics measured at an incident angle of 0 degrees, the average transmittance T in the wavelength range of 490 to 560 nm ＡＶＥ４９０－５６０（０°） is over 82%. (3-3) In the optical characteristics measured at an incident angle of 0 degrees, the average transmittance T in the wavelength range of 590 to 630 nm ＡＶＥ５９０－６３０（０°） is 50% or more. (3-4) Wavelength λ at which the transmittance is 50% at an incident angle of 0 degrees in the wavelength range of 600 to 800 nm ５０％（０°） and the wavelength λ at which the transmittance is 50% at an incident angle of 30 degrees ５０％（３０°） Absolute value of the difference between |λ ５０％（３０°） -λ ５０％（０°） | is 5 nm or less. (3-5) Average transmittance T in the wavelength range of 490 to 560 nm measured at an incident angle of 30 degrees ＡＶＥ４９０－５６０（３０°） is more than 80%. (3-6) The maximum absorption wavelength λ of the near-infrared absorbing dye (A) measured at an incident angle of 30 degrees ｍａｘ（Ａ）ＴＲ The minimum OD value in the wavelength range of ±10 nm is 3 or more. (3-7) Wavelength λ at which the transmittance is 50% at an incident angle of 0 degrees in the wavelength range of 600 to 800 nm ５０％（０°） and the wavelength λ at which the transmittance is 50% at an incident angle of 50 degrees ５０％（５０°） Absolute value of the difference between |λ ５０％（５０°） -λ ５０％（０°） | is 15 nm or less. (3-8) Average transmittance T in the wavelength range of 490 to 560 nm measured at an incident angle of 50 degrees ＡＶＥ４９０－５６０（５０°） is 70% or more.

2. 2. The optical filter according to claim 1, wherein the optical characteristics measured at an incident angle of 0 degrees satisfy the following requirement (3-1): (3-1) The maximum absorption wavelength λ of the near-infrared absorbing dye (A) ｍａｘ（Ａ）ＴＲ The minimum OD value in the wavelength range of ±10 nm is 4 or more.

3. The optical filter according to claim 1 or 2, further satisfying the following requirement (3-9): (3-9) The maximum absorption wavelength λ of the near-infrared absorbing dye (A) measured at an incident angle of 50 degrees ｍａｘ（Ａ）ＴＲ The minimum OD value in the wavelength range of ±10 nm is 3 or more.

4. 4. The optical filter according to claim 1, wherein, in the requirement (3-4), the absolute value |λ50%(30°)−λ50%(0°)| is 4 nm or less.

5. In the requirement (3-7), the absolute value |λ ５０％（５０°） -λ ５０％（０°） 5. The optical filter according to claim 1, wherein | is 10 nm or less.

6. 6. The optical filter according to claim 1, wherein the absorption layer satisfies the following (2-1) and (2-2): (2-1) Average internal transmittance T in the wavelength range of 490 to 560 nm ＡＶＥ４９０－５６０（ＡＬ） is over 88%. (2-2) Average internal transmittance T in the wavelength range of 590 to 630 nm ＡＶＥ５９０－６３０（ＡＬ） is 70% or more.

7. 7. The optical filter according to claim 6, wherein the absorption layer satisfies the following (2-3): (2-3) Wavelength λ at which the internal transmittance is 50% in the wavelength range of 600 to 700 nm ５０％ It has.

8. 7. The optical filter according to claim 6, wherein the absorption layer satisfies the following (2-4): (2-4) The total width of the wavelength range in which the internal transmittance is 30% or less in the wavelength range of 600 to 1200 nm is 250 nm or more.

9. 9. The optical filter according to claim 1, wherein the transparent resin is a polyimide resin.

10. 10. The optical filter according to claim 1, further comprising a transparent substrate, wherein the absorption layer and the dielectric multilayer film are each provided on a major surface of the transparent substrate.

11. The optical filter according to claim 10 , wherein the transparent substrate is made of a transparent resin material or glass.

12. 12. The optical filter according to claim 11, wherein the glass is a fluorophosphate glass doped with copper ions or a phosphate glass doped with copper ions.

13. An imaging device comprising the optical filter according to any one of claims 1 to 12.

14. An optical sensor comprising the optical filter according to any one of claims 1 to 12.

Images