optical filter

Abstract

The present invention relates to a filter having a substrate and a dielectric multilayer film, the dielectric multilayer film being stacked on at least one main surface side of the substrate and serving as the outermost layer, wherein the substrate has a resin film comprising a pigment (I) and a resin, the pigment (I) having a maximum absorption wavelength in dichloromethane in the range of 690 nm to 900 nm, the filter transmitting visible light and light in at least a portion of the wavelength range of 900 nm to 1000 nm, and satisfying all specific spectral characteristics (i-1) to (i-6).

Description

Technical Field

[0001] This invention relates to a filter that transmits visible light and a specific near-infrared light and blocks light between these two regions. Background Technology

[0002] The applications of imaging devices using solid-state imaging elements are being expanded to devices that record video day and night, such as surveillance cameras and vehicle cameras. In such devices, it is necessary to acquire both visible light-based (color) images and infrared light-based (black and white) images.

[0003] Therefore, research is underway on filters that, in addition to having the function of a near-infrared cutoff filter for transmitting visible light as described above and faithfully reproducing an image based on that visible light, also have the function of selectively transmitting specific near-infrared light, known as dual-bandpass filters (Patent Documents 1 and 2).

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2016-200771

[0007] Patent Document 2: Japanese Patent Application Publication No. 2019-124946 Summary of the Invention

[0008] The problem that the invention aims to solve

[0009] However, the filters described in Patent Documents 1 and 2 selectively transmit visible light and near-infrared light in the range of 800 nm to 900 nm, but do not transmit near-infrared light above 900 nm.

[0010] In recent years, due to the use of lasers around 950nm in sensors that sense human eye and body activity, there is a need for filters that can transmit a portion of near-infrared light above 900nm and block other near-infrared light that would otherwise become noise.

[0011] The purpose of this invention is to provide a filter that has excellent transmittance of visible light and certain near-infrared light, and is able to block other near-infrared light.

[0012] means for solving problems

[0013] The present invention provides a filter having the following configuration.

[0014] [1] A filter having a substrate and a dielectric multilayer film, the dielectric multilayer film being stacked on at least one main surface side of the substrate and serving as the outermost layer, wherein the substrate has a resin film comprising a pigment (I) and a resin, the pigment (I) having a maximum absorption wavelength in dichloromethane in the range of 690 nm to 900 nm, the filter transmitting visible light and light in at least a portion of the wavelength range of 900 nm to 1000 nm, and satisfying all of the following spectral characteristics (i-1) to (i-6):

[0015] (i-1) In the spectral transmittance curve under the condition of 0 degrees incident angle, the maximum transmittance T in the wavelength range of 700 nm to 900 nm is... 700-900(0deg)MAX Below 7%;

[0016] (i-2) In the spectral transmittance curve under the condition of an incident angle of 50 degrees, the maximum transmittance T in the wavelength range of 700 nm to 850 nm is... 700-850(50deg)MAX Less than 5%;

[0017] (i-3) In the spectral transmittance curve under the condition of 0 degrees incident angle, within the wavelength range of 900 nm to 950 nm, the shortest wavelength with a transmittance of 10% is set as IR10. 900-950(0deg) Set the shortest wavelength with a transmittance of 70% to IR70. 900-950(0deg) ,

[0018] at this time,

[0019] IR70 900-950(0deg) -IR10 900-950(0deg) Below 20nm;

[0020] (i-4) In the spectral transmittance curve under the condition of an incident angle of 50 degrees, within the wavelength range of 850 nm to 930 nm, the shortest wavelength with a transmittance of 10% is set as IR10. 850-930(50deg) Set the shortest wavelength with a transmittance of 70% to IR70. 850-930(50deg) ,

[0021] at this time,

[0022] IR70 850-930(50deg) -IR10 850-930(50deg) Below 50nm;

[0023] (i-5) In the spectral transmittance curve under the condition of 0 degrees incident angle, the shortest wavelength with a transmittance of 50% is set as IR50 in the range above 850 nm. 850(0deg) ,

[0024] In the spectral transmittance curve under an incident angle of 50 degrees, within the wavelength range above 850 nm, the shortest wavelength at which the transmittance is 50% is set as IR50. 850(50deg) ,

[0025] at this time

[0026] IR50 850(0deg) With IR50 850(50deg) The absolute value of the difference is less than 30nm;

[0027] (i-6) In the spectral transmittance curve under the condition of 0 degrees of incident angle, the average transmittance T in the wavelength range of 450 nm to 600 nm. 450-600(0deg)AVE It is over 60%.

[0028] Invention Effects

[0029] According to the present invention, a filter can be provided that exhibits excellent transmittance of visible light and specific near-infrared light, particularly light in the wavelength range of 900 nm to 1000 nm, excellent blocking properties of other near-infrared light, particularly light in the wavelength range of 700 nm to 900 nm, and suppresses the reduction in near-infrared light blocking properties at high incident angles. Attached Figure Description

[0030] Figure 1 A cross-sectional view illustrating an example of a filter according to one embodiment.

[0031] Figure 2 A cross-sectional view illustrating another example of a filter according to one embodiment.

[0032] Figure 3 A cross-sectional view illustrating another example of a filter according to one embodiment.

[0033] Figure 4 A cross-sectional view illustrating another example of a filter according to one embodiment.

[0034] Figure 5 A graph showing the spectral transmittance curve of the dielectric multilayer film in Example 2-1.

[0035] Figure 6 A graph showing the spectral transmittance curve of the filter in Example 3-1.

[0036] Figure 7 A graph showing the spectral transmittance curves of the filters in Examples 3-4. Detailed Implementation

[0037] The embodiments of the present invention will be described below.

[0038] In this specification, near-infrared absorbing pigments are sometimes referred to as "NIR pigments" and ultraviolet absorbing pigments are sometimes referred to as "UV pigments".

[0039] In this specification, the compound represented by formula (I) is referred to as compound (I). The same applies to compounds represented by other formulas. The pigment containing compound (I) is also referred to as pigment (I), and the same applies to other pigments. In addition, the group represented by formula (I) is also referred to as group (I), and the same applies to groups represented by other formulas.

[0040] In this specification, internal transmittance refers to the transmittance obtained by subtracting the effect of interface reflection from the measured transmittance, expressed by the formula {measured transmittance / (100 - reflectance)} × 100.

[0041] In this specification, the transmittance of the substrate, the transmittance of the resin film including cases where the resin contains pigments, and the transmittance measured by dissolving the pigments in solvents such as dichloromethane, when described as "transmittance," are all referred to as "internal transmittance." On the other hand, the transmittance of a filter having a dielectric multilayer film is the measured transmittance.

[0042] In this specification, a transmittance of 90% or more within a specific wavelength range means that the transmittance is not less than 90% across the entire wavelength range, i.e., the minimum transmittance within that wavelength range is 90% or more. Similarly, a transmittance of 1% or less within a specific wavelength range means that the transmittance is not greater than 1% across the entire wavelength range, i.e., the maximum transmittance within that wavelength range is 1% or less. The same applies to internal transmittance. The average transmittance and average internal transmittance within a specific wavelength range are the arithmetic mean of the transmittance and internal transmittance per 1 nm within that wavelength range.

[0043] Spectral characteristics can be measured using a UV-Vis spectrophotometer.

[0044] In this specification, the "~" sign indicating a numerical range includes both the upper and lower limits.

[0045] <Filter>

[0046] A filter according to one embodiment of the present invention (hereinafter also referred to as "this filter") is a filter having a substrate and a dielectric multilayer film, the dielectric multilayer film being stacked on at least one main surface side of the substrate and serving as the outermost layer, and the filter satisfying specific spectral characteristics described later.

[0047] Here, the substrate has a resin film comprising a pigment (I) and a resin, wherein the pigment (I) has a maximum absorption wavelength in dichloromethane in the range of 690 nm to 900 nm. The pigment (I) is an NIR pigment. By containing a pigment that absorbs near-infrared light in the substrate, the absorption characteristics of the substrate can be utilized to suppress the degradation of the spectral characteristics of the dielectric multilayer film at high incident angles, such as light leakage and noise generation in the near-infrared region. The pigments and resins will be explained later.

[0048] The structure of this filter will be illustrated using the accompanying drawings. Figures 1-4 A cross-sectional view illustrating an example of a filter according to one embodiment.

[0049] Figure 1 The filter 1A shown is an example of having a dielectric multilayer film 30 on one main surface side of the substrate 10. It should be noted that "having a specific layer on the main surface side of the substrate" is not limited to having the layer in contact with the main surface of the substrate, but also includes having other functional layers between the substrate and the layer.

[0050] Figure 2 The filter 1B shown is an example of having a dielectric multilayer film 30 on both main surfaces of the substrate 10.

[0051] Figure 3 The filter 1C shown is an example of a substrate 10 having a support 11 and a resin film 12 laminated on one main surface side of the support 11. The filter 1C further has a dielectric multilayer film 30 on the resin film 12 and a dielectric multilayer film 30 on the unlaminated main surface side of the resin film 12 on the support 11.

[0052] Figure 4 The filter 1D shown is an example of a substrate 10 having a support 11 and resin films 12 laminated on two main surfaces of the support 11. The filter 1D further has a dielectric multilayer film 30 on each resin film 12.

[0053] The filter of the present invention transmits visible light and light in at least a portion of the wavelength range of 900 nm to 1000 nm, and satisfies all of the following spectral characteristics (i-1) to (i-6).

[0054] (i-1) In the spectral transmittance curve under the condition of 0 degrees incident angle, the maximum transmittance T in the wavelength range of 700 nm to 900 nm is... 700-900(0deg)MAX Below 7%;

[0055] (i-2) In the spectral transmittance curve under the condition of an incident angle of 50 degrees, the maximum transmittance T in the wavelength range of 700 nm to 850 nm is... 700-850(50deg)MAX Less than 5%;

[0056] (i-3) In the spectral transmittance curve under the condition of 0 degrees incident angle, within the wavelength range of 900 nm to 950 nm, the shortest wavelength with a transmittance of 10% is set as IR10. 900-950(0deg) Set the shortest wavelength with a transmittance of 70% to IR70. 900-950(0deg) ,

[0057] at this time,

[0058] IR70 900-950(0deg) -IR10 900-950(0deg) Below 20nm;

[0059] (i-4) In the spectral transmittance curve under the condition of an incident angle of 50 degrees, within the wavelength range of 850 nm to 930 nm, the shortest wavelength with a transmittance of 10% is set as IR10. 850-930(50deg) Set the shortest wavelength with a transmittance of 70% to IR70. 850-930(50deg) ,

[0060] at this time,

[0061] IR70 850-930(50deg) -IR10 850-930(50deg) Below 50nm;

[0062] (i-5) In the spectral transmittance curve under the condition of 0 degrees incident angle, the shortest wavelength with a transmittance of 50% is set as IR50 in the range above 850 nm. 850(0deg) ,

[0063] In the spectral transmittance curve under an incident angle of 50 degrees, within the wavelength range above 850 nm, the shortest wavelength at which the transmittance is 50% is set as IR50. 850(50deg) ,

[0064] at this time,

[0065] IR50 850(0deg) With IR50 850(50deg) The absolute value of the difference is less than 30nm;

[0066] (i-6) In the spectral transmittance curve under the condition of 0 degrees of incident angle, the average transmittance T in the wavelength range of 450 nm to 600 nm. 450-600(0deg)AVE It is over 60%.

[0067] This filter, which satisfies all spectral characteristics (i-1) to (i-6), is a filter with excellent transmittance of visible light and specific near-infrared light, blocks other near-infrared light, and suppresses the reduction of near-infrared light blocking at high incident angles.

[0068] By satisfying the spectral characteristics (i-1), it means excellent barrier properties in the range of 700nm to 900nm. 700-900(0deg)MAX Preferably, it is 6.5% or less, more preferably 6% or less.

[0069] By satisfying the spectral characteristics (i-2), it means that the barrier properties are excellent even at high incident angles in the range of 700 nm to 850 nm. 700-850(50deg)MAX Preferably, it is 4.5% or less, more preferably 4% or less.

[0070] By satisfying the spectral characteristic (i-3), it means that the spectral transmittance curve has a steep slope in the NIR absorption band of 900 nm to 950 nm. IR70 900-950(0deg) -IR10 900-950(0deg) Preferably, the wavelength is 18.5 nm or less, and more preferably 17 nm or less.

[0071] By satisfying the spectral characteristics (i-4), it means that even at high incident angles, the slope of the spectral transmittance curve is steep in the NIR absorption band of 850 nm to 930 nm. IR70 850-930(50deg) -IR10 850-930(50deg) Preferably, the wavelength is 47.5 nm or less, and more preferably 45 nm or less.

[0072] By satisfying the spectral characteristics (i-5), it means that in the NIR absorption band above 850 nm, even at high incident angles, the shift is small and the color reproducibility is excellent. IR50 850(0deg) With IR50 850(50deg) The absolute value of the difference is preferably 29 nm or less, and more preferably 28 nm or less.

[0073] By satisfying the spectral characteristics (i-6), it means that the transmittance in the visible light region is excellent. 450-600(0deg)AVE Preferably, it is 75% or more, and more preferably 78% or more.

[0074] The filter preferably also satisfies the following spectral characteristics (i-7).

[0075] (i-7) In the spectral transmittance curve under the condition of 0 degrees of incident angle, the average transmittance T in the wavelength range of 930 nm to 950 nm. 930-950(0deg)AVE It is over 70%.

[0076] By satisfying the spectral characteristics (i-7), it means that the transmittance in the near-infrared region with wavelengths of 930nm to 950nm is excellent. 930-950(0deg)AVE Preferably, it is 74% or more, and more preferably 78% or more.

[0077] <Substrate>

[0078] In the filter of the present invention, the substrate has a resin film comprising the NIR pigment (I) and resin described later.

[0079] <Spectral properties of resin films>

[0080] The resin film preferably satisfies all of the following spectral characteristics (ii-1) to (ii-5).

[0081] (ii-1) In the spectral transmittance curve, the average internal transmittance T in the wavelength range of 450 nm to 600 nm 450-600AVE It is over 80%;

[0082] (ii-2) The wavelength IR50 when the internal transmittance is 50% is in the range of 620nm to 660nm;

[0083] (ii-3) In the spectral transmittance curve, the average internal transmittance T in the wavelength range of 700 nm to 830 nm 700-830AVE Less than 5%;

[0084] (ii-4) In the spectral transmittance curve, the maximum internal transmittance T in the wavelength range of 720 nm to 830 nm. 720-830MAX Less than 10%;

[0085] (ii-5) Within the wavelength range of 850nm to 950nm, the minimum wavelength when the internal transmittance is 20% is set as IR20, and the minimum wavelength when the internal transmittance is 80% is set as IR80.

[0086] at this time,

[0087] The absolute value of the difference between IR20 and IR80 is less than 50nm.

[0088] By satisfying the spectral characteristics (ii-1), it means that the transmittance in the visible light region is excellent.

[0089] T 450-600AVE Preferably, it is 82.5% or more, and more preferably 85% or more.

[0090] By satisfying the spectral characteristics (ii-2), it means that the transmittance in the red band is excellent, which can compensate for the oblique incidence shift of the dielectric multilayer film with excellent light blocking properties in the near-infrared region of 750 nm to 900 nm. IR50 is preferably in the range of 620 nm to 655 nm, and more preferably in the range of 625 nm to 650 nm.

[0091] By satisfying the spectral characteristics (ii-3), it means excellent blocking properties in the near-infrared region with wavelengths of 700 nm to 830 nm. 700-830AVEPreferably, it is 4% or less, more preferably 3% or less.

[0092] By satisfying the spectral characteristics (ii-4), it means excellent blocking properties in the near-infrared region with wavelengths of 720 nm to 830 nm. 720-830MAX Preferably, it is 8.5% or less, more preferably 7% or less.

[0093] By satisfying the spectral characteristics (ii-5), it means that the slope of the spectral transmittance curve is steep in the NIR absorption band of wavelength 850 nm to 950 nm. The absolute value of the difference between IR20 and IR80 is preferably 47.5 nm or less, more preferably 45 nm or less.

[0094] <NIR Pigment>

[0095] NIR pigment (I) is an NIR pigment that has a maximum absorption wavelength in dichloromethane in the range of 690 nm to 900 nm. By containing such a pigment, near-infrared light can be effectively blocked.

[0096] For pigment (I), it is preferable that the following characteristics (iii-1) are satisfied in the spectral internal transmittance curve measured by dissolving pigment (I) in resin in such a way that the internal transmittance at the maximum absorption wavelength in the resin constituting the resin film is 10%.

[0097] (iii-1) When the maximum absorption wavelength is set to D [nm] and the average internal transmittance in the range of 450nm to 600nm is set to E, E > 103.5 - (D / 100).

[0098] Characteristic (iii-1) defines the relationship between the maximum absorption wavelength and the transmittance. By satisfying the above characteristic (iii-1) through pigment (I), it means that the transmittance in the visible light region of 450nm to 600nm is high regardless of any maximum absorption wavelength.

[0099] As an NIR pigment (I), it can be composed of a single compound or contain two or more compounds in dichloromethane that have a maximum absorption wavelength in the range of 690 nm to 900 nm. From the viewpoint of effectively blocking light between the visible light region and the specific near-infrared light transmitted by this filter, it is preferable to contain three or more compounds in dichloromethane that have a maximum absorption wavelength in the range of 690 nm to 900 nm, and it is particularly more preferable to contain compounds selected by choosing one or more of compounds (A), (B), and (C) with the following characteristics.

[0100] Compound (A) has a maximum absorption wavelength in dichloromethane in the range of wavelengths greater than or equal to 690 nm and less than 735 nm.

[0101] Compound (B) exhibits maximum absorption wavelength in dichloromethane in the range of wavelengths greater than or equal to 735 nm and less than 830 nm.

[0102] Compound (C) exhibits maximum absorption wavelength in dichloromethane in the range of wavelengths greater than or equal to 830 nm and less than 900 nm.

[0103] Compound (A) is preferably selected from squaric acid. At least one of salt pigment, phthalocyanine pigment, and anthocyanin pigment.

[0104] Compound (B) is preferably selected from squaric acid. At least one of salt pigment, phthalocyanine pigment, and anthocyanin pigment.

[0105] Compound (C) is preferably selected from squaric acid. At least one of salt pigments, phthalocyanine pigments, anthocyanins, and diamine pigments.

[0106] As a NIR pigment (I), from the viewpoints of transmittance in the visible light region, solubility in resin, and durability, squaric acid is preferred. Salt pigments or anthocyanin pigments.

[0107] <Square acid inner> Salt pigment >

[0108] Squamous acid Salt pigments are preferably compounds represented by formula (I) or formula (II) below.

[0109] It should be noted that within the squaric acid... When a salt pigment compound contains two or more identical symbols, these symbols can be the same or different. The same applies to anthocyanins.

[0110] <Square acid inner> Salt compound (I) >

[0111]

[0112] The symbols in the above formula are as follows.

[0113] R 24 and R 26 Each of the following can independently represent a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group or an alkoxy group with 1 to 20 carbon atoms, an acyl group with 1 to 10 carbon atoms, an aryl group with 6 to 11 carbon atoms, an aralkyl group with 7 to 18 carbon atoms that may have substituents and may have oxygen atoms between carbon atoms, and -NR. 27 R 28 (R 27 and R28 Each independently represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, or a -C(=O)-R group. 29 (R 29 (Hydrogen atom, halogen atom, hydroxyl group, may have substituents and may contain unsaturated bonds between carbon atoms, oxygen atom, saturated or unsaturated ring structure, hydrocarbon group with 1 to 25 carbon atoms), -NHR 30 or -SO2-R 30 (R 30 Each of the above groups consists of one or more hydrogen atoms that may be substituted with halogen atoms, hydroxyl groups, carboxyl groups, sulfonyl groups, or cyano groups, and may contain unsaturated bonds, oxygen atoms, saturated or unsaturated ring structures, or hydrocarbon groups with 1 to 25 carbon atoms, or groups represented by the following formula (S) (R). 41 and R 42 Each can independently represent a hydrogen atom, a halogen atom, or an alkyl group or an alkoxy group having 1 to 10 carbon atoms. (k is 2 or 3).

[0114]

[0115] R 21 and R 22 They can connect with each other and form 5- or 6-membered heterocycles A and R together with nitrogen atoms. 22 and R 25 They can connect with each other and form 5- or 6-membered heterocycles B and R together with nitrogen atoms. 21 and R 23 They can connect with each other and form 5- or 6-membered heterocyclic C atoms together with nitrogen atoms.

[0116] As R in the case of forming heterocyclic A 21 and R 22 The bonded divalent group -Q- represents an alkylene or alkyleneoxy group, wherein the hydrogen atom of the alkylene or alkyleneoxy group may be replaced by 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 and a substituent.

[0117] As R in the case of forming heterocyclic B 22 and R 25 The bonded divalent group -X 1 -Y 1 - and R in the case of forming heterocyclic C 21 and R 23 The bonded divalent group -X 2 -Y 2 -(The side bonded to nitrogen is X) 1 and X 2 ), X 1 and X2 Each is a group represented by the following formula (1x) or (2x), Y 1 and Y 2 Each is a group represented by any one of the following formulas (1y) to (5y). In X 1 and X 2 When each of the groups is represented by the following formula (2x), Y 1 and Y 2 Each can be a single bond, and in this case, there can be oxygen atoms between carbon atoms.

[0118]

[0119] In formula (1x), each of the four Zs independently represents a hydrogen atom, a hydroxyl group, an alkyl group with 1 to 6 carbon atoms or an alkoxy group with 1 to 6 carbon atoms, or -NR. 38 R 39 (R 38 and R 39 Each can independently represent an alkyl group having 1 to 20 hydrogen atoms. 31 ~R 36 Each 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 It represents an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 10 carbon atoms.

[0120] R 27 R 28 R 29 R 31 ~R 37 R without the formation of heterocycles 21 ~R 23 and R 25 Each can bond with any of these groups to form a 5-membered or 6-membered ring. R 31 and R 36 Direct bonding is possible, R 31 and R 37 They can be bonded directly.

[0121] R without heterocyclic formation 21 R 22 R 23 and R 25 Each of the following can be independently represented as a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group having 1 to 20 carbon atoms 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, or an aralkyl group having 7 to 18 carbon atoms that may have substituents and may have oxygen atoms between carbon atoms.

[0122] As for compound (I), for example, compounds represented by any of formulas (I-1) to (I-3) can be listed. From the viewpoints of solubility in resin, heat resistance and light resistance in resin, and visible light transmittance of the resin layer containing the compound, the compound represented by formula (I-1) is particularly preferred.

[0123]

[0124] The symbols in equations (I-1) to (I-3) are defined in the same way as the same symbols in equation (I), and the preferred methods are also the same.

[0125] In compound (I-1), as X 1 Preferred group (2x) is used as Y. 1 Preferably, a single bond or a group (1y). In this case, as R 31 ~R 36 Preferably, it is an alkyl group having 1 to 3 hydrogen atoms, more preferably a hydrogen atom or a methyl group. It should be noted that, as -Y 1 -X 1 Specifically, divalent organic groups represented by formulas (11-1) to (12-3) can be listed.

[0126] -C(CH3)2-CH(CH3)- ……(11-1)

[0127] -C(CH3)2-CH2- ……(11-2)

[0128] -C(CH3)2-CH(C2H5)- ……(11-3)

[0129] -C(CH3)2-C(CH3)(nC3H7)-……(11-4)

[0130] -C(CH3)2-CH2-CH2-……(12-1)

[0131] -C(CH3)2-CH2-CH(CH3)- ……(12-2)

[0132] -C(CH3)2-CH(CH3)-CH2-……(12-3)

[0133] Furthermore, in compound (I-1), considering the steepness of the change near the boundary between the visible and near-infrared regions in the spectral transmittance curve, R... 21 More preferably, it is a group represented by formula (4-1) or formula (4-2).

[0134]

[0135] In equations (4-1) and (4-2), R 71 ~R 75 Independently represents an alkyl group having 1 to 4 hydrogen atoms, halogen atoms, or carbon atoms.

[0136] In compound (I-1), R 24 Preferred is -NR 27 R 28 As -NR 27 R 28 From the viewpoint of solubility in resins and coating solvents, -NH-C(=O)-R is preferred. 29 or -NH-SO2-R 30 .

[0137] In compound (I-1) R 24 -NH-C(=O)-R 29 The compound is shown in formula (I-11).

[0138]

[0139] R 23 and R 26 The atom is preferably a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms or an alkoxy group having 1 to 6 carbon atoms, and more preferably all of them are hydrogen atoms.

[0140] As R 29 Preferably, the substituent is an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 10 carbon atoms, or an aralkyl group having 7 to 18 carbon atoms and having an oxygen atom between the carbon atoms. Examples of substituents include: hydroxyl, carboxyl, sulfonyl, cyano, alkyl group having 1 to 6 carbon atoms, fluoroalkyl group having 1 to 6 carbon atoms, alkoxy group having 1 to 6 carbon atoms, and acyloxy group having 1 to 6 carbon atoms.

[0141] As R 29 Preferably, the group is selected from alkyl groups with 1 to 17 carbon atoms that are straight-chain, branched, or cyclic, phenyl groups that can be substituted by alkoxy groups with 1 to 6 carbon atoms, and aralkyl groups with 7 to 18 carbon atoms that can have oxygen atoms between carbon atoms.

[0142] As R 29 Alternatively, the following groups may be used independently and preferably: the group is a hydrocarbon group with 5 to 25 carbon atoms, in which one or more hydrogen atoms may be replaced by hydroxyl, carboxyl, sulfonyl or cyano groups and may contain unsaturated bonds, oxygen atoms, saturated or unsaturated ring structures between carbon atoms, and having at least one branched chain.

[0143] As compound (I-11), more specifically, the compounds shown in the table below can be listed. Additionally, the compounds shown in the table below are in squaric acid. The symbols on the left and right sides of the salt skeleton have the same meaning.

[0144] [Table 1]

[0145]

[0146] Among these compounds (I-11), compounds (I-11-11) to (I-11-15), (I-11-26) to (I-11-30) are preferred in terms of transmittance in the visible light region and solubility in resin.

[0147] In compound (I-1) R 24 -NH-SO2-R 30 The compound is shown in formula (I-12).

[0148]

[0149] R 23 and R 26 The atom is preferably a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms or an alkoxy group having 1 to 6 carbon atoms, and more preferably all of them are hydrogen atoms.

[0150] From the perspective of lightfastness, R 30 Independently preferred are alkyl groups having 1 to 12 branched carbon atoms, alkoxy groups having 1 to 12 branched carbon atoms, or hydrocarbon groups having 6 to 16 carbon atoms with an unsaturated ring structure. Examples of unsaturated ring structures include: benzene, toluene, xylene, furan, benzofuran, etc. 30 More preferably, it is an alkyl group having 1 to 12 branched carbon atoms or an alkoxy group having 1 to 12 branched carbon atoms. It should be noted that, in the representation of R... 30 In each of the groups, some or all of the hydrogen atoms can be replaced by halogen atoms, especially fluorine atoms.

[0151] As compound (I-12), more specifically, the compounds shown in the table below can be listed. Additionally, the compounds shown in the table below are in squaric acid. The symbols on the left and right sides of the salt skeleton have the same meaning.

[0152] [Table 2]

[0153]

[0154] Among these compounds (I-12), compounds (I-12-11) to (I-12-15), (I-12-26) to (I-12-30) are preferred in terms of transmittance in the visible light region and solubility in the resin.

[0155] <Square acid inner> Salt compound (II) >

[0156]

[0157] The symbols in the above formula are as follows.

[0158] Each ring Z is independently a 5-membered or 6-membered ring with 0 to 3 heteroatoms, and the hydrogen atoms in ring Z can be substituted.

[0159] R 1 and R 2 They can connect with each other and form heterocycles A1,R together with nitrogen atoms. 2 and R 3 They can connect with each other and form heterocycles B1 and R together with nitrogen atoms. 1 The carbon atoms or heteroatoms constituting ring Z can connect with each other and form a heterocycle C1 together with a nitrogen atom. In this case, the hydrogen atoms in heterocycles A1, B1, and C1 can be substituted. R without heterocycle formation... 1 and R 2 Each can independently represent a hydrogen atom, a halogen atom, or a hydrocarbon group, which may contain unsaturated bonds, heteroatoms, saturated or unsaturated ring structures between carbon atoms, and may have substituents. R 4 And R in the case of no heterocycle formation 3 Each of the above can independently represent a hydrogen atom, a halogen atom, or an alkyl or alkoxy group, wherein each alkyl or alkoxy group may contain heteroatoms between carbon atoms and may have substituents.

[0160] As for compound (II), for example, compounds represented by any of formulas (II-1) to (II-3) can be listed. From the viewpoint of solubility in resin and visible light transmittance in resin, compounds represented by formula (II-3) are particularly preferred.

[0161]

[0162] In equations (II-1) and (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 that may have substituents; R 3 ~R 6Each can independently represent a hydrogen atom, a halogen atom, or an alkyl group having 1 to 10 carbon atoms that may have substituents.

[0163] In equation (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 that may have substituents; R 7 and R 8 Each can independently represent a hydrogen atom, a halogen atom, or an alkyl group having 1 to 5 carbon atoms that may have substituents.

[0164] Considering factors such as solubility in resins and visible light transmittance, R in compounds (II-1) and (II-2) 1 and R 2 Alkyl groups having 1 to 15 carbon atoms are preferred, alkyl groups having 7 to 15 carbon atoms are more preferred, and R is even more preferred. 1 and R 2 At least one of them is a branched alkyl group having 7 to 15 carbon atoms, with R being particularly preferred. 1 and R 2 Both are branched alkyl groups with 8 to 15 carbon atoms.

[0165] Considering factors such as solubility in transparent resins and visible light transmittance, R in compound (II-3) 1 Alkyl groups having 1 to 15 carbon atoms are preferred, more preferably alkyl groups having 1 to 10 carbon atoms, and particularly preferably ethyl or isopropyl.

[0166] From the perspectives of visible light transmittance and ease of synthesis, R 4 The preferred atoms are hydrogen atoms or halogen atoms, with hydrogen atoms being particularly preferred.

[0167] R 7 and R 8 The preferred components are hydrogen atoms, halogen atoms, and alkyl groups having 1 to 5 carbon atoms that can be replaced by halogen atoms; more preferably, hydrogen atoms, halogen atoms, and methyl groups.

[0168] R 9 ~R 12 The preferred components are hydrogen atoms, halogen atoms, and alkyl groups having 1 to 5 carbon atoms that can be replaced by halogen atoms.

[0169] As -CR 9 R 10 -CR 11 R 12- Examples of divalent organic groups represented by the following groups (13-1) to (13-5) can be listed.

[0170] -CH(CH3)-C(CH3)2- ……(13-1)

[0171] -C(CH3)2-CH(CH3)- ……(13-2)

[0172] -C(CH3)2-CH2- ……(13-3)

[0173] -C(CH3)2-CH(C2H5)- ……(13-4)

[0174] -CH(CH3)-C(CH3)(CH2-CH(CH3)2)-……(13-5)

[0175] As compounds (II-3), more specifically, the compounds shown in the table below can be listed. Additionally, the compounds shown in the table below are in squaric acid. The symbols on the left and right sides of the salt skeleton have the same meaning.

[0176] [Table 3]

[0177]

[0178] Compounds (I) through (II) can each be manufactured by known methods. Compound (I) can be manufactured by the methods described in U.S. Patent No. 5,543,086, U.S. Patent Application Publication No. 2014 / 0061505, and International Publication No. 2014 / 088063. Compound (II) can be manufactured by the methods described in International Publication No. 2017 / 135359.

[0179] <Anthocyanins>

[0180] Anthocyanins are preferably compounds represented by formula (III), formula (IV), formula (V) or formula (VI) below.

[0181] <Anthocyanin compounds (III), (IV)>

[0182]

[0183] The symbols in the above formula are as follows.

[0184] R 101 ~R 109 and R 121 ~R 131Each can independently represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 15 carbon atoms that may have substituents, or an aryl group having 5 to 20 carbon atoms that may have substituents. R 110 ~R 114 and R 132 ~R 136 Each can be independently represented by a hydrogen atom, a halogen atom, or an alkyl group having 1 to 15 carbon atoms.

[0185] X - It represents a monovalent anion.

[0186] n1 and n2 are either 0 or 1. (This is related to the inclusion of -(CH2)) n1 - carbon ring and containing -(CH2) n2 The hydrogen atom bonded to the carbon ring can be replaced by a halogen atom, an alkyl group having 1 to 15 carbon atoms that can have a substituent, or an aryl group having 5 to 20 carbon atoms that can have a substituent.

[0187] In the above, alkyl groups (including those with alkoxy groups) can be straight-chain, branched-chain, or saturated-ring structures. Aryl groups refer to groups bonded via carbon atoms of aromatic rings such as benzene rings, naphthyl rings, biphenyl rings, furan rings, thiophene rings, and pyrrole rings that constitute aromatic compounds. Examples of substituents that can be alkyl groups with 1 to 15 carbon atoms, alkoxy groups with 1 to 15 carbon atoms, or aryl groups with 5 to 20 carbon atoms include halogen atoms and alkoxy groups with 1 to 10 carbon atoms.

[0188] In equations (III) and (IV), R 101 and R 121 Preferably, it is an alkyl group having 1 to 15 carbon atoms or an aryl group having 5 to 20 carbon atoms. From the viewpoint of maintaining high visible light transmittance in the resin, it is more preferably an alkyl group having 1 to 15 carbon atoms with a branched chain.

[0189] In equations (III) and (IV), R 102 ~R 105 R 108 R 109 R 122 ~R 127 R 130 and R 131 Each atom is preferably a hydrogen atom, an alkyl group having 1 to 15 carbon atoms, an alkoxy group having 1 to 15 carbon atoms, or an aryl group having 5 to 20 carbon atoms. From the viewpoint of obtaining high visible light transmittance, a hydrogen atom is more preferred.

[0190] In equations (III) and (IV), R 110 ~R114 and R 132 ~R 136 Each of the components is preferably a hydrogen atom or an alkyl group having 1 to 15 carbon atoms, and from the viewpoint of obtaining high visible light transmittance, a hydrogen atom is more preferred.

[0191] R 106 R 107 R 128 and R 129 Each of the following is preferably a hydrogen atom, an alkyl group having 1 to 15 carbon atoms, or an aryl group having 5 to 20 carbon atoms (which may include straight-chain, cyclic, or branched alkyl groups), and more preferably a hydrogen atom or an alkyl group having 1 to 15 carbon atoms. Additionally, R 106 and R 107 Preferably, the same group, R 128 and R 129 Preferably, they are the same group.

[0192] As X - Examples include: I - BF4 - PF6 - ClO4 - Anions represented by formulas (X1) and (X2), preferably BF4. - or PF6 - .

[0193]

[0194] In the following description, pigment (III) excluding R 101 ~R 114 The parts other than this are also called the skeleton (III). The same applies to the pigments (IV).

[0195] Compounds in formula (III) with n1 = 1 are shown in formula (III-1), and compounds in formula (III) with n1 = 0 are shown in formula (III-2).

[0196]

[0197] In equations (III-1) and (III-2), R 101 ~R 114 and X - The same applies as in equation (III). R 115 ~R 120 Each can independently represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 15 carbon atoms that may have substituents, an alkoxy group having 1 to 15 carbon atoms that may have substituents, or an aryl group having 5 to 20 carbon atoms that may have substituents. R 115 ~R120 Each of the following is preferably a hydrogen atom, an alkyl group having 1 to 15 carbon atoms, or an aryl group having 5 to 20 carbon atoms (which may include straight-chain, cyclic, or branched alkyl groups), and more preferably a hydrogen atom or an alkyl group having 1 to 15 carbon atoms. Additionally, R 115 ~R 120 Preferably, they are the same group.

[0198] Compounds in formula (IV) with n2 = 1 are shown in formula (IV-1), and compounds in formula (IV) with n2 = 0 are shown in formula (IV-2).

[0199]

[0200] In equations (IV-1) and (IV-2), R 121 ~R 136 and X - The same applies as in equation (IV). R 137 ~R 142 Each can independently represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 15 carbon atoms that may have substituents, an alkoxy group having 1 to 15 carbon atoms that may have substituents, or an aryl group having 5 to 20 carbon atoms that may have substituents. R 137 ~R 142 Each of the following is preferably a hydrogen atom, an alkyl group having 1 to 15 carbon atoms, or an aryl group having 5 to 20 carbon atoms (which may include straight-chain, cyclic, or branched alkyl groups), and more preferably a hydrogen atom or an alkyl group having 1 to 15 carbon atoms. Additionally, R 137 ~R 142 Preferably, they are the same group.

[0201] As compounds represented by formula (III-1), compounds represented by formula (III-2), compounds represented by formula (IV-1), and compounds represented by formula (IV-2), more specifically, each can be listed as compounds whose atoms or groups bonded to each skeleton are those shown in the table below. In all the compounds shown in the table below, R... 101 ~R 109 The left and right sides of the formula are identical. 121 ~R 131 The left and right sides of the formula are the same.

[0202] R in the table below 110 -R 114 And R in the table below 132 -R 136 The atom or group bonded to the central benzene ring in each formula is represented by "H" when all five atoms are hydrogen atoms. In R... 110 -R114 If any one of the elements is a substituent and the others are hydrogen atoms, only the symbol for the substituent and the combination of the substituents are recorded. For example, "R 112 The description of "-C(CH3)3" indicates R 112 It is -C(CH3)3 and otherwise consists of hydrogen atoms. For R 132 -R 136 Same here.

[0203] R in Table 4 115 -R 120 and R in Table 6 137 -R 142 The atom or group bonded to the central cyclohexane ring in formulas (III-1) and (IV-1) is represented by "H" if all six atoms are hydrogen atoms. In R 115 -R 120 If any one of the elements is a substituent and the others are hydrogen atoms, only the symbol of the substituent and the combination of the substituents are recorded. For R 137 -R 142 Same here.

[0204] R in Table 5 115 -R 118 and R in Table 7 137 -R 140 The atom or group bonded to the central cyclopentane ring in formulas (III-2) and (IV-2) is represented by "H" if all four atoms are hydrogen atoms. In R 115 -R 118 If any one of the elements is a substituent and the others are hydrogen atoms, only the symbol of the substituent and the combination of the substituents are recorded. For R 137 -R 140 Same here.

[0205] X is not shown in the table below. - However, among all compounds, X - BF4 - or PF6 - .

[0206] [Table 4]

[0207]

[0208] As pigments (III-1), among these pigments, pigments (III-1-1) to (III-1-5) are preferred in terms of transmittance in the visible light region and solubility in resin.

[0209] [Table 5]

[0210]

[0211] As pigments (III-2), among these pigments, pigments (III-2-1) to (III-2-5) are preferred in terms of transmittance in the visible light region and solubility in the resin.

[0212] [Table 6]

[0213]

[0214] As pigments (IV-1), among these pigments, pigments (IV-1-1) to (IV-1-5) are preferred in terms of transmittance in the visible light region and solubility in resin.

[0215] [Table 7]

[0216]

[0217] As pigments (IV-2), among these pigments, pigments (IV-2-1) to (IV-2-5) are preferred in terms of transmittance in the visible light region and solubility in resin.

[0218] For pigments (III) and (IV), as mentioned above, the backbones differ, resulting in different wavelength ranges of maximum absorption. For pigment (III), although the maximum absorption wavelength also depends on the type and combination of atoms and groups bonded to the backbone, the maximum absorption wavelength is in the range of approximately 760 nm to approximately 830 nm. For pigment (IV), although the maximum absorption wavelength also depends on the type and combination of atoms and groups bonded to the backbone, the maximum absorption wavelength is in the range of approximately 800 nm to approximately 900 nm.

[0219] Furthermore, for pigment (III), the maximum absorption wavelength differs when n1 in the backbone is 1 and when n1 is 0. Although the maximum absorption wavelength also depends on the type and combination of atoms and groups bonded to the backbone, the maximum absorption wavelength is in the range of approximately 760 nm to approximately 800 nm when n1 is 1, and in the range of approximately 800 nm to approximately 830 nm when n1 is 0.

[0220] Similarly, for pigments (IV), the maximum absorption wavelength differs when n2 is 1 and when n2 is 0. Although the maximum absorption wavelength also depends on the type and combination of atoms and groups bonded to the backbone, the maximum absorption wavelength is in the range of approximately 800 nm to approximately 830 nm when n2 is 1, and in the range of approximately 830 nm to approximately 900 nm when n2 is 0.

[0221] Pigment (III) and pigment (IV) can be manufactured, for example, by the methods described in Dyes and pigments 73 (2007) 344-352 and J. Heterocyclic chem, 42, 959 (2005).

[0222] <Anthocyanin compound (V)>

[0223]

[0224] The symbols in equation (V) are as follows.

[0225] R 1 ~R 7 Each can independently represent a hydrogen atom, a halogen atom, a sulfonyl group, a hydroxyl group, a cyano group, a nitro group, a carboxyl group, a phosphate group, an alkyl group having 1 to 10 carbon atoms that may have substituents, an alkoxy group having 1 to 10 carbon atoms that may have substituents, or an acyloxy group having 1 to 10 carbon atoms that may have substituents.

[0226] In equation (V), R 1 ~R 7 The left and right sides of the expression can be the same or different, but it is preferable that they are all the same.

[0227] Examples of substituents that can be alkyl groups having 1 to 10 carbon atoms, alkoxy groups having 1 to 10 carbon atoms, or acyloxy groups having 1 to 10 carbon atoms include halogen atoms or alkoxy groups having 1 to 10 carbon atoms.

[0228] In this specification, unless otherwise stated, alkyl groups can be straight-chain, branched, cyclic, or combinations thereof. The same applies to alkyl groups containing alkoxy groups. Examples of halogen atoms include fluorine, chlorine, bromine, and iodine atoms, with fluorine and chlorine atoms being preferred.

[0229] Considering factors such as ease of synthesis, R 1 Each atom is preferably a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or an acyloxy group having 1 to 10 carbon atoms, and is particularly preferred to be a hydrogen atom.

[0230] R 2 ~R 7Each of the following is preferably composed of a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group having 1 to 10 carbon atoms that may have substituents, an alkoxy group having 1 to 10 carbon atoms that may have substituents, or an acyloxy group having 1 to 10 carbon atoms that may have substituents. From the viewpoint of ease of synthesis, R... 2 ~R 7 Each of the components is preferably an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms, and may have a substituent.

[0231] From the viewpoint of solubility in resins or solvents, R 6 ~R 7 At least one of them is preferably an alkyl group having 1 to 10 carbon atoms, more preferably a secondary or tertiary branched alkyl group having 10 or fewer carbon atoms, and even more preferably tert-butyl, isopropyl, or isobutyl.

[0232] R 2 ~R 5 R 6 ~R 7 Two adjacent rings can connect to each other to form 5- to 8-membered rings. The rings can be aliphatic or aromatic.

[0233] Formula (V) optionally includes Z. Z is a 5-membered ring or a 6-membered ring. Having Z is preferred from a durability point of view. It should be noted that the hydrogen atom bonded to the carbon atom constituting Z can be replaced by an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 10 carbon atoms.

[0234] In this specification, unless otherwise stated, aryl refers to a group bonded via carbon atoms of aromatic rings such as benzene rings, naphthalene rings, biphenyl rings, furan rings, thiophene rings, pyrrole rings, etc., which constitute aromatic compounds.

[0235] X - It represents a monovalent anion.

[0236] X - PF6 is preferred. - [Rf-SO2] - [N(Rf-SO2)2] - Or BF4 - Rf represents an alkyl group substituted with at least one fluorine atom, preferably a perfluoroalkyl group having 1 to 8 carbon atoms, and particularly preferably -CF3. With such an anionic structure, pigment compounds (V) with excellent lightfastness can be obtained.

[0237] R 8 Represents a hydrogen atom, a halogen atom, or -Y 5 -R 10 (Y 5The bonds are single bonds, ether bonds (-O-), sulfonyl bonds (-SO2-), ester bonds (-C(=O)-O- or -OC(=O)-), or urea bonds (-NH-C(=O)-NH-), R 10 It can be an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 30 carbon atoms that can have substituents.

[0238] R 8 Preferably, hydrogen atoms, halogen atoms, and Y atoms are used. 5 -Y for single bond 5 -R 10 More preferably, it is a hydrogen atom, a chlorine atom, an alkyl group having 1 to 10 carbon atoms, or an aryl group having 6 to 10 carbon atoms that can be substituted by a halogen atom.

[0239] For formula (V), more specifically, the compounds bonded to each skeleton can be listed as shown in the table below. In all the compounds shown in the table below, R... 1 ~R 7 The left and right sides of the expression are identical.

[0240] [Table 8]

[0241]

[0242] Among these compounds (V), compounds (V-1) to (V-4) are preferred in terms of transmittance in the visible light region and solubility in the resin.

[0243] Regarding the method for manufacturing compound (V), R in compound (V) is used. 1 ~R 5 R 7 It is a hydrogen atom and X - BF4 - The method for manufacturing compound (V1) will be described, but the method for manufacturing compound (V1) is not limited thereto.

[0244] The route to obtain compound (V1) is shown below.

[0245]

[0246] (1) Mix salicylaldehyde (a) with R 6 The alkyne compound (b) reacts to give compound (c).

[0247] (2) Compound (c) is reacted with 4-dimethylaminopyridine to obtain compound (d).

[0248] (3) React compound (d) with methylmagnesium bromide and tetrafluoroboric acid to obtain compound (e).

[0249] (4) Make compound (e) react with R 8 The aldehyde diphenylamine hydrochloride (f) of the group reacts to give compound (V1).

[0250] In X - Change to PF6 - In this case, it is possible to synthesize by using hexafluorophosphate instead of tetrafluoroboric acid in step (3) above, in which X - Change to [Rf-SO2] - In this case, it is possible to synthesize by using Rf-SO3H instead of tetrafluoroboric acid in step (3) above, in which X - Change to [N(Rf-SO2)2] - In this case, it can be synthesized by using NH(Rf-SO2)2 instead of tetrafluoroboric acid in step (3) above.

[0251] <Anthocyanin compound (VI)>

[0252]

[0253] The symbols in equation (VI) are as follows.

[0254] X - It is a monovalent anion. Examples of monovalent anions include PF6. - BF4 - N(SO2CF3)2 - CF3SO3 - ReO4 - ClO4 - Cl - ,Br - I - BPh4 - B(C6F5)4 - CF3COO - C(SO2CF3)3 - p-Toluenesulfonyl anion, etc.

[0255] It should be noted that Ph represents phenyl.

[0256] From the perspective of improving the lightfastness of compound (VI), X - Preferred from PF6 - BF4 - N(SO2CF3)2 - Choose from.

[0257] m can be 0 or 1, preferably 1.

[0258] When m is 0, R1 is a monovalent anionic group. Examples of monovalent anionic groups include anionic groups represented by any of (C1) to (C6) below.

[0259]

[0260] In equations (C1) to (C6), R 201 ~R 214 Each can independently represent a hydrogen atom, an aryl group having 5 to 20 carbon atoms, or an alkyl group having 1 to 10 carbon atoms that may have substituents. Examples of substituents include halogen atoms or alkoxy groups having 1 to 10 carbon atoms.

[0261] When m is 1, R1 can be a hydrogen atom, a halogen atom, an alkyl group with 1 to 12 carbon atoms, an aryl group with 6 to 12 carbon atoms that may have substituents, an aralkyl group with 7 to 13 carbon atoms that may have substituents, or -NR9R. 10 .

[0262] Examples of halogen atoms in R1 include fluorine, chlorine, bromine, and iodine atoms.

[0263] The alkyl group in R1 preferably has 1 to 10 carbon atoms, more preferably 1 to 6. Examples of alkyl groups with 1 to 6 carbon atoms include methyl, ethyl, propyl, isopropyl, isobutyl, tert-butyl, etc.

[0264] From a synthetic point of view, methyl groups are particularly preferred.

[0265] Aryl groups with 6 to 12 carbon atoms in R1 can be exemplified by groups bonded via carbon atoms of the aromatic rings (e.g., benzene rings, naphthalene rings, biphenyl rings, furan rings, thiophene rings, pyrrole rings, etc.) that constitute aromatic compounds.

[0266] From the perspective of not compromising the transmittance of the blue band, phenyl is preferred.

[0267] Aryl groups having 7 to 13 carbon atoms in R1 can be exemplified by: straight-chain or branched saturated or unsaturated hydrocarbon groups or saturated cyclic hydrocarbon groups that are substituted with one or more aryl groups and may contain a saturated ring structure.

[0268] From the viewpoint of not impairing the transmittance in the blue band, aryl groups containing phenyl groups are preferred.

[0269] Substituents that R1 can have include, for example: halogen atoms (fluorine, chlorine, bromine, iodine), alkyl groups with 1 to 12 carbon atoms, alkoxy groups with 1 to 12 carbon atoms, hydroxyl groups, carboxyl groups, sulfonyl groups, cyano groups, amino groups, N-substituted amino groups, nitro groups, alkoxycarbonyl groups, carbamoyl groups, N-substituted carbamoyl groups, imide groups, etc.

[0270] R9 and R 10 Each of them is independently an alkyl group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms that may have substituents, or a carbonyl group having 1 to 12 carbon atoms that may have substituents.

[0271] R9 and R 10 Specific examples of alkyl and aryl groups, and R9 and R 10 The specific examples of substituents that can be present are the same as those for R1.

[0272] As R9 and R 10 Carbonyl groups with 1 to 12 carbon atoms include, for example, acetyl, acetyl propionyl, benzoyl, trifluoroacetyl, pentafluoropropionyl, etc.

[0273] From the perspective of not impairing the transmittance of the blue band and from the perspective of synthesis, R1 is preferably a hydrogen atom, methyl, phenyl, diphenylamino, N-ethylamino, N-ethyl-2,2,2-trifluoroacetamido, and more preferably a hydrogen atom, methyl, or phenyl.

[0274] R2 to R7 are each independently a hydrogen atom, a halogen atom, an alkyl group with 1 to 12 carbon atoms, a cycloalkyl group with 3 to 12 carbon atoms, an aryl group with 6 to 12 carbon atoms that may have substituents, or an aralkyl group with 7 to 13 carbon atoms that may have substituents. Two adjacent R2 to R7 can be connected to each other to form a 5-membered to 8-membered ring.

[0275] Specific examples of halogen atoms, alkyl groups, aryl groups with 6 to 12 carbon atoms, and aralkyl groups in R2 to R7, as well as specific examples of substituents that R2 to R7 may have, are the same as those in R1.

[0276] The cycloalkyl group in R2 to R7 preferably has 3 to 10 carbon atoms, more preferably 6 to 10. Examples of cycloalkyl groups with 6 to 10 carbon atoms include cyclohexyl, cycloheptyl, cyclooctyl, and adamantyl.

[0277] From the perspective of not impairing the transmittance of the blue band and from the perspective of synthesis, R2 to R5 are preferably hydrogen atoms or alkyl groups having 1 to 12 carbon atoms, and more preferably hydrogen atoms.

[0278] Furthermore, from the viewpoint of improving the transmittance of the blue band, R6 to R7 are preferably alkyl groups with 1 to 12 carbon atoms or aryl groups with 6 to 12 carbon atoms that may have substituents, more preferably secondary alkyl groups with 1 to 12 carbon atoms, tertiary alkyl groups with 1 to 12 carbon atoms, or phenyl groups with substituents at the 2 and 6 positions, and even more preferably isopropyl, tert-butyl, sec-butyl, 2,6-dimethylphenyl, 2,4,6-trimethylphenyl, 2,6-diisopropylphenyl, or 2,4,6-triisopropylphenyl.

[0279] Furthermore, compound (VI) is more preferably a compound represented by the following formula (VI-1).

[0280]

[0281] The symbols in equation (VI-1) are as follows.

[0282] X - The definitions of R1 to R5 are the same as in equation (VI).

[0283] R 11 and R 12 Each is independently an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms.

[0284] R 11 and R 12 The alkyl group preferably has 1 to 8 carbon atoms, more preferably 1 to 5. Examples of alkyl groups with 1 to 5 carbon atoms include methyl, ethyl, isopropyl, and tert-butyl.

[0285] R 11 and R 12 The alkoxy group in the alkoxy group preferably has 1 to 8 carbon atoms, more preferably 1 to 6. Examples of alkoxy groups with 1 to 6 carbon atoms include methoxy, ethoxy, and isopropoxy.

[0286] Through R 11 and R 12 The pigment A is an alkyl group or an alkoxy group with 1 to 12 carbon atoms, and adopts a conformation in which the phenyl group is orthogonal to the π-conjugated plane. This π-conjugation between the phenyl group and pigment A is cleaved, resulting in an inductive electron-withdrawing effect. Through this electron-withdrawing effect, compound (VI-1) exhibits absorption in the near-infrared region of 720 nm to 760 nm and can improve transmittance in the blue band.

[0287] From a synthetic point of view, R 11 and R 12 Preferably, it is an alkyl group having 1 to 12 carbon atoms, more preferably an alkyl group having 1 to 5 carbon atoms, and even more preferably methyl, ethyl, or isopropyl.

[0288] R 13 It consists of hydrogen atoms, alkyl groups having 1 to 12 carbon atoms, or alkoxy groups having 1 to 12 carbon atoms.

[0289] R 13 The alkyl group preferably has 1 to 8 carbon atoms, more preferably 1 to 5. Examples of alkyl groups with 1 to 5 carbon atoms include methyl, ethyl, isopropyl, and tert-butyl.

[0290] R 13 The alkoxy group in the alkoxy group preferably has 1 to 8 carbon atoms, more preferably 1 to 6. Examples of alkoxy groups with 1 to 6 carbon atoms include methoxy, ethoxy, and isopropoxy.

[0291] From a synthetic point of view, R 13 Preferably, it is an alkyl group having 1 to 12 carbon atoms, more preferably an alkyl group having 1 to 5 carbon atoms, and even more preferably methyl, ethyl, or isopropyl.

[0292] Additionally, in R 13 In the absence of hydrogen atoms, from a synthetic point of view, R 13 Preferred and R 11 R 12 same.

[0293] As a compound (VI-1), more specifically, compounds in which the atoms or groups bonded to each skeleton are those shown in the table below can be listed.

[0294] [Table 9]

[0295]

[0296] From the viewpoint of ease of synthesis, compounds represented by formulas (VI-1-1) and (VI-1-2) are preferred.

[0297] Furthermore, from the viewpoint of improving the lightfastness of compound (VI), X - Preferred from PF6 - BF4 - N(SO2CF3)2 - Choose from.

[0298] (Method for manufacturing compound (VI))

[0299] Regarding the method of manufacturing compound (VI), the method of manufacturing compound (VI-1-a) in which R1 to R5 in compound (VI-1) are hydrogen atoms will be used for explanation, but the method of manufacturing compound (VI) is not limited to this.

[0300] The route to obtain compound (VI-1-a) is shown below.

[0301]

[0302] <Step 1>

[0303] The starting material (g), trimethylsilylacetylene, tetra(triphenylphosphine)palladium (0), cuprous iodide, and diethylamine were added to a flask. The flask was degassed, purged with nitrogen, and heated with stirring. After the reaction was complete, the solvent was removed by vacuum distillation, water was added, and the mixture was extracted with dichloromethane. The dichloromethane was removed by vacuum distillation, and the mixture was purified to obtain the intermediate (h).

[0304] <Step 2>

[0305] Intermediate (h) and methanol were added to a round-bottom flask and the mixture was chilled. Potassium carbonate was then added and the mixture was stirred under a nitrogen atmosphere. After the reaction was complete, the potassium carbonate was removed from the reaction system by filtration, and the filtrate was distilled under reduced pressure. Water was added to the resulting liquid, and the mixture was extracted with dichloromethane. The dichloromethane was removed by reduced pressure distillation, and the mixture was purified to obtain intermediate (i).

[0306] <Step 3>

[0307] Intermediate (i) and tetrahydrofuran were added to a gaiwan flask and stirred under a nitrogen atmosphere. Butyllithium was added and stirred. Then, ethyl formate dissolved in tetrahydrofuran was added and stirred. After the reaction was complete, water was added to stop the reaction, and extraction was performed using dichloromethane. The dichloromethane was removed by vacuum distillation, and the resulting solid was washed to obtain intermediate (j).

[0308] <Step 4>

[0309] Intermediate (j), dichloromethane, and manganese oxide were added to a grate flask and stirred under a nitrogen atmosphere. After the reaction was complete, the reaction solution was filtered to remove the manganese oxide, and the filtrate was distilled under reduced pressure. The resulting powder was washed to obtain intermediate (k).

[0310] <Step 5>

[0311] Intermediate (k), p-toluenesulfonic acid monohydrate, methanol, and toluene were added to a round-bottom flask and stirred. The solvent was then removed by vacuum distillation, followed by the addition of methanol and concentrated hydrochloric acid, and stirring. After the reaction was complete, the reaction solution was chilled, water was added to stop the reaction, and extraction was performed using dichloromethane. The dichloromethane was removed by vacuum distillation, followed by the addition of toluene and trifluoromethanesulfonic acid, and stirring. After the reaction was complete, the reaction solution was chilled, water was added to stop the reaction, and the toluene layer was extracted. The toluene was removed by vacuum distillation, purified, and the resulting powder was washed to obtain intermediate (l).

[0312] <Step 6>

[0313] Intermediate (l) and tetrahydrofuran were added to a gaiwan flask and stirred. Methylmagnesium bromide was then added, and the mixture was heated and stirred under a nitrogen atmosphere. After the reaction was complete, the reaction solution was gradually added to a 10% (w / w) acidic aqueous solution, and the reaction was stopped by stirring. The solution was extracted with dichloromethane, the dichloromethane layer was washed with water, and then the dichloromethane was removed by vacuum distillation. The resulting powder was washed to obtain intermediate (m).

[0314] Examples of 10% by mass acidic aqueous solutions include: hexafluorophosphate aqueous solution, tetrafluoroboric acid aqueous solution, bis(trifluoromethanesulfonyl)imide aqueous solution, trifluoromethanesulfonic acid aqueous solution, perrhenic acid aqueous solution, perchloric acid aqueous solution, hydrochloric acid aqueous solution, hydrobromic acid aqueous solution, hydroiodic acid aqueous solution, etc.

[0315] <Step 7>

[0316] Intermediate (m), malondialdehyde diphenylamine hydrochloride, sodium acetate, acetic acid, and acetic anhydride were added to a flask and heated with stirring under a nitrogen atmosphere. After the reaction was complete, the reaction solution was chilled, water was added, and the solution was then filtered to recover the powder. The powder was purified, and the resulting solid was washed to obtain compound (VI-1-a).

[0317] The content of NIR pigment (I) in the resin film is preferably 0.1 to 25 parts by mass relative to 100 parts by mass of resin, more preferably 0.3 to 15 parts by mass. It should be noted that when two or more compounds are combined, the above content refers to the sum of all compounds.

[0318] <Other Pigments>

[0319] In addition to NIR pigments, resin films may also contain other pigments, such as UV pigments.

[0320] Specific examples of UV pigments can be listed as follows: Zazoles, anthocyanins, naphthalenedicarboximides, diazoles, Azides Pigments include azole alkyl groups, naphthalenedicarboxylic acid groups, styryl groups, anthracene groups, cyclic carbonyl groups, and triazole groups. Furthermore, UV pigments can be used alone or in combination with two or more types.

[0321] <Substrate Structure>

[0322] The substrate in this filter can be a single-layer structure or a multi-layer structure. Furthermore, the material used as the substrate can be any transparent material that transmits visible light in the range of 400nm to 700nm; it can be organic or inorganic, without any particular restrictions.

[0323] When the substrate has a single-layer structure, a resin substrate composed of a resin film containing resin and NIR pigment (I) is preferred.

[0324] When the substrate has a multilayer structure, it is preferable to have a composite substrate containing a resin film of NIR pigment (I) laminated on at least one main surface of the support. In this case, the support preferably comprises a transparent resin or a transparent inorganic material.

[0325] There are no restrictions on the type of resin used, as long as it is transparent. One or more transparent resins selected from polyester resins, acrylic resins, epoxy resins, olefin-thiol resins, polycarbonate resins, polyether resins, polyaryl ester resins, polysulfone resins, polyethersulfone resins, poly(p-phenylene) resins, polyaryl ether phosphine oxide resins, polyamide resins, polyimide resins, polyamide-imide resins, polyolefin resins, cyclic olefin resins, polyurethane resins, and polystyrene resins can be used. These resins can be used alone or in combination of two or more.

[0326] From the viewpoints of the spectral characteristics, glass transition temperature (Tg), and adhesion of the resin film, it is preferable to select one or more resins selected from polyimide resin, polycarbonate resin, polyester resin, and acrylic resin.

[0327] When using multiple compounds as NIR pigments (I) and other pigments, these compounds can be contained in the same resin film or in different resin films.

[0328] As a transparent inorganic material, glass and crystalline materials are preferred.

[0329] Examples of glasses that can be used as supports include: absorbing glasses containing copper ions (near-infrared absorbing glasses) such as fluorophosphate glasses and phosphate glasses, soda-lime glass, borosilicate glass, alkali-free glass, and quartz glass.

[0330] As a glass, chemically strengthened glass can be obtained by replacing alkali metal ions with small ionic radii (e.g., Li ions, Na ions) present on the main surface of the glass plate with alkali metal ions with larger ionic radii (e.g., Na ions or K ions for Li ions, and K ions for Na ions) through ion exchange at a temperature below the glass transition temperature.

[0331] Examples of crystalline materials that can be used as supports include: quartz, lithium niobate, sapphire, and other birefringent crystals.

[0332] As a support, inorganic materials are preferred from the perspective of shape stability related to long-term reliability of optical and mechanical properties, and from the perspective of manufacturability during filter manufacturing. Glass and sapphire are particularly preferred.

[0333] The resin film can be formed by dissolving or dispersing a pigment (I), resin or resin raw material components, and other components as needed, in a solvent to prepare a coating solution, coating it onto a support, drying it, and further curing it as needed. The support can be the support contained in this filter, or it can be a peelable support used only during the formation of the resin film. Furthermore, the solvent can be any dispersion medium that can stably disperse the resin or a solvent that can dissolve it.

[0334] In addition, the coating liquid may contain surfactants to improve voids caused by tiny air bubbles, depressions caused by the adhesion of foreign matter, and pinholes during the drying process. Furthermore, methods such as dip coating, cast coating, or spin coating can be used in the coating liquid application. The coating liquid is applied to a support and then dried to form a resin film. If the coating liquid contains a transparent resin component, further curing treatments such as thermosetting or photocuring are performed.

[0335] Furthermore, the resin film can also be manufactured into a film shape by extrusion molding. When the substrate is a single-layer structure (resin substrate) consisting of a resin film containing pigment (I), the resin film can be used directly as the substrate. When the substrate is a multilayer structure (composite substrate) having a support and a resin film containing pigment (I) laminated on at least one main surface of the support, the substrate can be manufactured by laminating the film onto the support and integrating it using methods such as hot pressing.

[0336] A filter may contain one layer of resin film or two or more layers of resin film. When there are two or more layers of resin film, each layer may have the same composition or different compositions.

[0337] When the substrate is a single-layer structure (resin substrate) composed of a resin film containing pigment (I), the thickness of the resin film is preferably 20 μm to 150 μm.

[0338] When the substrate is a multilayer structure (composite substrate) having a support and a resin film containing pigment (I) laminated on at least one main surface of the support, the thickness of the resin film is preferably 0.3 μm to 20 μm. It should be noted that when the filter has two or more resin films, the total thickness of each resin film is preferably within the above range.

[0339] There are no particular restrictions on the shape of the substrate; it can be in the form of blocks, plates, or films.

[0340] Furthermore, from the viewpoint of reducing warpage during the formation of a dielectric multilayer film and lowering the height of the optical element, the thickness of the substrate is preferably 300 μm or less. When the substrate is a resin substrate composed of a resin film, the thickness of the substrate is preferably 50 μm to 300 μm. When the substrate is a composite substrate having a support and a resin film, the thickness of the substrate is preferably 50 μm to 300 μm.

[0341] This filter can have other constituent elements such as inorganic particles that generate absorption by controlling the transmission and absorption of light within a specific wavelength range. Specific examples of inorganic particles include: ITO (indium tin oxide), ATO (antimony-doped tin oxide), cesium tungstate, and lanthanum boride. ITO particles and cesium tungstate particles have high visible light transmittance and light absorption over a wide range of infrared wavelengths greater than 1200 nm, thus they can be used when infrared light blocking is required.

[0342] <Dielectric Multilayer Film>

[0343] In this filter, a dielectric multilayer film is stacked on at least one main surface side of the substrate and serves as the outermost layer.

[0344] In this filter, the dielectric multilayer film preferably satisfies all of the following spectral characteristics (iv-1) to (iv-6).

[0345] (iv-1) Average transmittance T in the wavelength range of 450 nm to 600 nm 450-600AVE It is over 93%;

[0346] (iv-2) In the wavelength range of 600nm to 800nm, the wavelength VL50 with a transmittance of 50% is in the range of 680nm to 750nm;

[0347] (iv-3) Average transmittance T in the wavelength range of 750 nm to 900 nm 750-900AVE Less than 10%;

[0348] (iv-4) In the wavelength range of 850 nm to 950 nm, the wavelength IR50 with a transmittance of 50% 850-950 Within the range of 900nm to 930nm;

[0349] (iv-5) Average transmittance T in the wavelength range of 930 nm to 950 nm 930-950AVE It is over 80%;

[0350] (iv-6) In the wavelength range of 950 nm to 1100 nm, the wavelength IR50 with 50% transmittance. 950-1100 Within the range of 1000nm to 1080nm.

[0351] By satisfying the spectral characteristics (iv-1), it means that the transmittance in the visible light region is excellent. 450-600AVE Preferably, it is 94% or more, and more preferably 95% or more.

[0352] By satisfying the spectral characteristics (iv-2), it means excellent transmittance in the red band and excellent light blocking properties in the near-infrared region of 750 nm to 900 nm. VL50 is preferably in the range of 685 nm to 750 nm, and more preferably in the range of 690 nm to 750 nm.

[0353] By satisfying the spectral characteristics (iv-3), it means excellent light blocking properties in the near-infrared region of 750nm to 900nm. 750-900AVE Preferably, it is 8.5% or less, more preferably 7% or less.

[0354] By satisfying the spectral characteristics (iv-4), it signifies excellent light blocking in the near-infrared region of 750 nm to 900 nm and excellent transmittance in the near-infrared region of 930 nm to 950 nm. IR50 850-950 Preferably, it is in the range of 905nm to 930nm, and more preferably in the range of 910nm to 930nm.

[0355] By satisfying the spectral characteristics (iv-5), it means excellent transmittance in the near-infrared region with wavelengths of 930 nm to 950 nm. 930-950AVE Preferably, it is 81.5% or more, and more preferably 83% or more.

[0356] By satisfying the spectral characteristics (iv-6), it means excellent transmittance in the near-infrared region of 930nm–950nm and excellent light blocking properties in the near-infrared region above 1080nm. IR50 950-1100Preferably, it is in the range of 1005nm to 1080nm, and more preferably in the range of 1010nm to 1075nm.

[0357] In this filter, it is preferable that at least one of the dielectric multilayer films is designed as a near-infrared reflective layer (hereinafter also referred to as an NIR reflective layer). It is preferable that the other of the dielectric multilayer films is designed as an NIR reflective layer, a reflective layer having a reflective region other than the near-infrared region, or an anti-reflective layer.

[0358] A NIR reflective layer is a dielectric multilayer film designed to block light in the near-infrared region. For example, an NIR reflective layer may transmit visible light and a specific near-infrared region, while primarily reflecting a light-blocking region of the resin film (acting as an absorption layer) and exhibiting wavelength selectivity for light other than the specific near-infrared region. It should be noted that the reflective region of the NIR reflective layer may also include the light-blocking region of the resin film in the near-infrared region. The NIR reflective layer may also be appropriately designed to block light in wavelength ranges other than the near-infrared region, such as near-ultraviolet light, in addition to its NIR reflective properties.

[0359] The NIR reflective layer is, for example, composed of a dielectric multilayer film obtained by alternately stacking a low-refractive-index dielectric film (low-refractive-index film) and a high-refractive-index dielectric film (high-refractive-index film). The refractive index of the high-refractive-index film is preferably 1.6 or higher, more preferably 2.2 to 2.5. Examples of materials for the high-refractive-index film include Ta₂O₅, TiO₂, and Nb₂O₅. Among these, TiO₂ is preferred considering factors such as film formation properties, reproducibility of refractive index, and stability.

[0360] On the other hand, the refractive index of the low-refractive-index film is preferably less than 1.6, more preferably greater than or equal to 1.45 and less than 1.55. Examples of materials that can be used for low-refractive-index films include SiO2 and SiO2. x N y Considering factors such as reproducibility, stability, and economy of film formation, SiO2 is preferred.

[0361] To enable the NIR reflective layer to transmit visible light and specific near-infrared light, one approach is to combine multiple multilayer films with different spectral characteristics when transmitting and selecting the desired wavelength.

[0362] For example, the thickness and number of layers can be adjusted by the materials that make up the membrane.

[0363] From the viewpoint of controlling the transmission and blocking wavelengths, the total number of layers of the dielectric multilayer film constituting the NIR reflective layer is preferably 50 or more, more preferably 90 or more, and even more preferably 130 or more.

[0364] In addition, the overall thickness of the reflective layer is preferably 2μm to 15μm.

[0365] In addition, vacuum film formation processes such as CVD, sputtering, and vacuum evaporation can be used in the formation of dielectric multilayer films; wet film formation processes such as spraying and immersion can also be used.

[0366] The specified spectral characteristics can be imparted using a single NIR reflective layer (a set of dielectric multilayer films), or using two or more NIR reflective layers. When there are two or more NIR reflective layers, each reflective layer can have the same or different configurations. Typically, the two reflective layers consist of multiple reflective layers with different reflection bands. With two reflective layers, one layer can be configured as a near-infrared reflective layer that blocks short-wavelength light in the near-infrared region, and the other layer can be configured as a near-infrared / near-ultraviolet reflective layer that blocks both long-wavelength and near-ultraviolet light in the same near-infrared region.

[0367] Examples of antireflective layers include: multilayer dielectric films, intermediate refractive index media, and moth-eye structures with gradually changing refractive index. Among these, multilayer dielectric films are preferred from the perspective of optical efficiency and productivity. Similar to reflective layers, antireflective layers are obtained by alternately stacking dielectric films.

[0368] This filter, for example, when used in imaging devices such as digital cameras, can provide an imaging device with excellent color reproduction. An imaging device using this filter includes a solid-state imaging element, an imaging lens, and the filter itself. The filter can be used, for example, disposed between the imaging lens and the solid-state imaging element, or directly adhered to the solid-state imaging element, imaging lens, etc., of the imaging device using an adhesive layer.

[0369] Example

[0370] Next, the invention will be described in more detail through examples.

[0371] The ultraviolet-visible spectrophotometer (UH-4150 model manufactured by Hitachi High Technology Co., Ltd.) was used to measure the various spectral characteristics.

[0372] It should be noted that the spectral characteristics without a clearly stated incident angle are values ​​measured at an incident angle of 0 degrees (perpendicular to the main surface of the filter).

[0373] The pigments used in each example are described below.

[0374] Compound 1 (squamous acid) Salt pigment): synthesized according to U.S. Patent No. 5,543,086.

[0375] Compound 2 (squamous acid) Salt pigment): synthesized according to U.S. Patent No. 5,543,086.

[0376] Compound 3 (squamous acid) Salt pigment): synthesized according to the description in U.S. Patent Application Publication No. 2014 / 0061505 and International Publication No. 2014 / 088063.

[0377] Compound 4 (anthocyanin): synthesized by the synthesis example 1 described later.

[0378] Compound 5 (squamous acid) Salt pigment): Synthesized according to International Publication No. 2017 / 135359.

[0379] Compound 6 (anthocyanin): synthesized by synthesis example 2 described later.

[0380] Compounds 7, 8, and 9 (anthocyanins): synthesized according to Dyes and pigments 73 (2007) 344-352.

[0381] Compound 10: synthesized according to Japanese Patent No. 4081149.

[0382] Compound 11: Synthesized according to International Publication No. 2020 / 129909.

[0383] Compound 12: synthesized according to Japanese Patent Application Publication No. 2014-25016.

[0384] Compound 1

[0385] Compound 2

[0386] Compound 3

[0387] Compound 4

[0388] Compound 5

[0389] Compound 6

[0390] Compound 7

[0391] Compound 8

[0392] Compound 9

[0393] Compound 10

[0394] Compound 11

[0395] Yihewu 12

[0396] <Synthetic Example 1: Synthesis of Compound 4>

[0397]

[0398] <Step 1>

[0399] To a 1000 mL flask, add 100 g (406.4 mmol) of iodotrimethylbenzene, 59.9 g (609.5 mmol) of trimethylsilylacetylene, 6.1 g (5.28 mmol) of tetrakis(triphenylphosphine)palladium(O), 2.0 g (10.6 mmol) of cuprous iodide, and diethylamine (500 mL). Degas the flask, then purge with nitrogen, and heat and stir at 50 °C for 6 hours. After the reaction is complete, remove the solvent by vacuum distillation, add water, and extract with dichloromethane. Remove the dichloromethane by vacuum distillation, then purify by rapid column chromatography (hexane) to obtain 90.1 g (quantitative) of intermediate ia.

[0400] <Step 2>

[0401] Intermediate ia (90.1 g, 416.4 mmol) and methanol (600 mL) were added to a 1 L flask and the mixture was chilled. Potassium carbonate (167.9 g, 1214.8 mmol) was added, and the mixture was stirred at room temperature for 1 hour under a nitrogen atmosphere. After the reaction was complete, the potassium carbonate was removed from the reaction solution by filtration through diatomaceous earth (Celite), and the filtrate was distilled under reduced pressure. Water was added to the resulting orange-yellow liquid, and the solution was extracted with dichloromethane. The dichloromethane was removed by distillation under reduced pressure, and the solution was then purified by rapid column chromatography (hexane) to obtain 58.5 g (quantitative) of intermediate ib.

[0402] <Step 3>

[0403] Intermediate ib (22.0 g, 152.6 mmol) and tetrahydrofuran (125 mL) were added to a 1000 mL pear-shaped flask and stirred at -78 °C under a nitrogen stream. Butyllithium (1.6 mol / L, in hexane) (100 mL) was added using a dropping funnel, and the mixture was stirred at -78 °C for 1 hour. Then, ethyl formate (5.7 g, 76.3 mmol) dissolved in 20 mL of tetrahydrofuran was added using a dropping funnel, and the mixture was stirred at -78 °C for 5 hours, followed by stirring at 0 °C for 1.5 hours. After the reaction was complete, water was added to stop the reaction, and the mixture was extracted with dichloromethane. The dichloromethane was removed by vacuum distillation, and the resulting yellowish-brown solid was washed with hexane to give 13.4 g (56%) of intermediate ic.

[0404] <Step 4>

[0405] Intermediate ic (25.9 g, 83.7 mmol), dichloromethane (500 mL), and manganese oxide (36.4 g, 418.7 mmol) were added to a 1000 mL pear-shaped flask and stirred at room temperature for 1 hour under a nitrogen atmosphere. After the reaction was complete, the reaction solution was filtered to remove the manganese oxide, and the filtrate was distilled under reduced pressure. The resulting yellow powder was washed with hexane to obtain 23.6 g (92%) of intermediate id.

[0406] <Step 5>

[0407] To a 1000 mL p-bellied flask, add intermediate id (21.9 g, 69.7 mmol), p-toluenesulfonic acid monohydrate (2.4 g, 13.9 mmol), methanol (230 mL), and toluene (230 mL), and stir at 110 °C for 8 hours. Then, remove the solvent by vacuum distillation, add methanol (280 mL) and concentrated hydrochloric acid (70 mL), and stir at 70 °C for one night. After the reaction is complete, chill the reaction solution, add water to stop the reaction, and then extract with dichloromethane. Remove the dichloromethane by vacuum distillation, then add toluene (350 mL) and trifluoromethanesulfonic acid (21.0 g, 139.9 mmol), and stir at 100 °C for 2.5 hours. After the reaction is complete, chill the reaction solution, add water to stop the reaction, and extract the toluene layer. Toluene was removed by vacuum distillation, followed by purification using rapid column chromatography (hexane / dichloromethane) to obtain a pink powder. The pink powder was washed with hexane to yield 15.5 g (67%) of intermediate ie.

[0408] <Step 6>

[0409] Intermediate ie (6.0 g, 18.0 mmol) and tetrahydrofuran (75 mL) were added to a 500 mL pear-shaped flask and stirred at 0 °C. Then, methyl magnesium bromide (13% tetrahydrofuran solution) (49.7 g, 54.1 mmol) was added, and the mixture was heated and stirred at 70 °C for 1 hour under a nitrogen atmosphere. After the reaction was complete, the reaction solution was gradually added to a 10% hexafluorophosphate aqueous solution (350 mL) at 0 °C and stirred at 0 °C for 10 minutes to stop the reaction. The solution was extracted with dichloromethane, the dichloromethane layer was washed with water, and then the dichloromethane was removed by vacuum distillation. The resulting yellow powder was washed with hexane, yielding 8.2 g (95%) of intermediate if.

[0410] <Step 7>

[0411] Intermediate if (1.75 g, 3.7 mmol), malondialdehyde diphenylamine hydrochloride (0.47 g, 1.84 mmol), sodium acetate (0.72 g, 8.82 mmol), acetic acid (15 mL), and acetic anhydride (15 mL) were added to a 200 mL round-bottom flask and heated and stirred at 80 °C for 45 minutes under a nitrogen atmosphere. After the reaction was complete, the reaction solution was chilled, water was added, and the solution was filtered to recover the dark green powder. The recovered powder was purified by rapid column chromatography (dichloromethane / ethyl acetate), and the solid was washed with a hexane:ethyl acetate solution of 1:1 to give 1.4 g (88%) of compound 4.

[0412] <Synthetic Example 2: Synthesis of Compound 6>

[0413]

[0414] <Step 1>

[0415] 3,3-Dimethyl-1-butyne (13 g, 160 mmol) and tetrahydrofuran (40 mL) were added to a 1 L flask, cooled to -78 °C and stirred. Butyllithium (1.6 M, in hexane, 100 mL) was added dropwise, and the mixture was stirred at -78 °C for 1 hour. Then, salicylaldehyde (10 g, 82 mmol) dissolved in tetrahydrofuran (80 mL) was added, and the mixture was stirred at room temperature for 3 hours. After the reaction was complete, the mixture was quenched with a saturated ammonium chloride solution and extracted with ethyl acetate. After removing the solvent, manganese dioxide (35 g, 400 mmol) and acetone (80 mL) were added, and the mixture was stirred at room temperature for 16 hours. After the reaction was complete, the solvent in the filtrate was removed by filtration, and the filtrate was purified by column chromatography to give 6.1 g (37%) of the intermediate.

[0416] <Step 2>

[0417] Intermediate Ig (6.1 g, 30 mmol) and N,N-dimethylformamide (120 mL) were added to a 500 mL round-bottom flask. The mixture was cooled to 0 °C and stirred. 4-Dimethylaminopyridine (0.37 g, 3.0 mmol) was then added, and the reaction was carried out at room temperature for 16 hours. After the reaction was completed, water was added to quench the reaction, and the mixture was extracted with ethyl acetate to remove the solvent. The extract was then purified by column chromatography to obtain 4.2 g (70%) of intermediate Ih.

[0418] <Step 3>

[0419] Intermediate Ih (5.0 g, 25 mmol) was added to a 500 mL pear-shaped flask, followed by tetrahydrofuran (60 mL). The mixture was cooled to 0 °C and stirred. Methylmagnesium bromide (1 M, in tetrahydrofuran, 37 mL) was added dropwise, and the reaction was allowed to proceed at room temperature for 5 hours. After the reaction was complete, ice water was added to quench the reaction, followed by the addition of 60% hexafluorophosphate aqueous solution (150 mL), and the mixture was stirred at room temperature for 30 minutes. The solvent was removed by extraction with dichloromethane, and the precipitated solid was then washed with ethyl acetate to give 7.2 g (84%) of intermediate II.

[0420] <Step 4>

[0421] Intermediate ii (5.2 g, 15 mmol), malondialdehyde diphenylamine hydrochloride (1.9 g, 7.5 mmol), sodium acetate (3.0 g, 36 mmol), acetic acid (60 mL), and acetic anhydride (60 mL) were added to a 500 mL flask and stirred at 80 °C for 2 hours. After the reaction was complete, water was added, and the precipitated solid was recovered by filtration and purified by column chromatography to obtain 1.8 g (41%) of compound 6.

[0422] <Spectral Characteristics of IR Pigments>

[0423] The polyimide resin (C-3G30G manufactured by Mitsubishi Gas Chemical Co., Ltd.) was dissolved in an organic solvent (cyclohexanone: γ-butyrolactone = 1:1 mass ratio) at a concentration of 8.5% by mass.

[0424] Each pigment compound was added to the polyimide resin solution prepared above at a ratio of 6 parts by mass to 100 parts by mass of resin, and the mixture was heated at 50°C and stirred for 2 hours. The pigment-containing resin solution was coated onto a glass substrate (alkali glass, D263 manufactured by Schott AG) and dried to obtain a resin film (coated film) with a thickness of 1 μm.

[0425] The internal spectral transmittance curve was calculated using the spectral transmittance and spectral reflectance curves of the glass plate with the resin film, and normalized to a transmittance of 10% at the maximum absorption wavelength.

[0426] The spectral characteristics are shown in the table below.

[0427] [Table 10]

[0428]

[0429] <Examples 1-1 to 1-6: Spectral Characteristics of Resin Films>

[0430] The polyimide resin (C-3G30G manufactured by Mitsubishi Gas Chemical Co., Ltd.) was dissolved in an organic solvent (cyclohexanone: γ-butyrolactone = 1:1 mass ratio) at a concentration of 8.5% by mass.

[0431] Each compound was added to the polyimide resin solution prepared above in the manner specified in the table below, relative to 100 parts by mass of resin, and the mixture was heated at 50°C while stirring for 2 hours. The pigment-containing resin solution was coated onto a glass substrate (alkali glass, D263 manufactured by Schott AG) and dried to obtain a resin film (coated film) with a thickness of 3 μm.

[0432] The spectral characteristics are shown in the table below.

[0433] It should be noted that Examples 1-1 to 1-6 are for reference only.

[0434] [Table 11]

[0435]

[0436] Examples 1-1 to 1-3 exhibit a wide absorption width in the near-infrared region and high visible light transmittance.

[0437] The absorption width in the near-infrared region of Examples 1-4 is narrow.

[0438] The absorption width in the near-infrared region of Examples 1-5 is slightly narrower.

[0439] Examples 1-6 exhibit a wide absorption width in the near-infrared region but low transmittance in the visible light region. This is attributed to the fact that increasing the amount of compound (B) broadens the absorption width, resulting in absorption also occurring in the visible light region.

[0440] <Example 2-1: Spectral characteristics of dielectric multilayer films>

[0441] A reflective layer was designed comprising a 69-layer dielectric multilayer film 1 and a 76-layer dielectric multilayer film 2 obtained by alternately stacking TiO2 and SiO2 films.

[0442] The table below shows the spectral characteristics of the combination of dielectric multilayer film 1 and dielectric multilayer film 2.

[0443] In addition, Figure 5 The figure shows the spectral transmittance curves of the combination of dielectric multilayer film 1 and dielectric multilayer film 2.

[0444] It should be noted that Example 2-1 is a reference example.

[0445] [Table 12]

[0446]

[0447] <Example 3-1: Spectral Characteristics of a Filter>

[0448] A filter is obtained by sequentially stacking the dielectric multilayer film 2 prepared in Example 2-1, the glass substrate (alkali glass, D263 manufactured by Schott AG), the resin film of Example 1-1, and the dielectric multilayer film 1 prepared in Example 2-1.

[0449] <Examples 3-2 to 3-5: Spectral Characteristics of Filters>

[0450] Except that the resin membrane was changed to the resin membrane shown in the table below, the filter was obtained in the same manner as in Example 3-1.

[0451] The spectral characteristics are shown in the table below.

[0452] In addition, the spectral transmittance curve of the filter in Example 3-1 is shown in... Figure 6 In the example, the spectral transmittance curves of the filters in Examples 3-4 are shown. Figure 7 middle.

[0453] It should be noted that Examples 3-1 to 3-3 are examples, and Examples 3-4 to 3-5 are comparative examples.

[0454] [Table 13]

[0455]

[0456] The filters in Examples 3-1 to 3-3 exhibit excellent spectral characteristics, including good transmittance in the visible light region and near-infrared region around 950 nm, light blocking properties in the 700 nm to 900 nm range, steepness around 900 nm, and oblique incidence characteristics around 900 nm.

[0457] The results of the filters in Examples 3-4 and 3-5 show that although the transmittance in the visible light region and the near-infrared light region around 950 nm is good, the light blocking properties in the 700 nm to 900 nm range, the steepness around 900 nm, and the oblique incidence characteristics around 900 nm are low.

[0458] Although the present invention has been described in detail and with reference to specific embodiments, various changes or modifications can be made without departing from the spirit and scope of the invention, which will be apparent to those skilled in the art. This application is based on Japanese Patent Application No. 2020-171326, filed on October 9, 2020, the contents of which are incorporated herein by reference.

[0459] Industrial practicality

[0460] The filter of this invention exhibits excellent transmittance of visible light and certain near-infrared light, while blocking other near-infrared light, and possesses good near-infrared light blocking characteristics that suppress the decrease in near-infrared light blocking at high incident angles. It is useful in applications where high-performance information acquisition devices such as conveyor cameras and sensors are increasingly being developed.

[0461] Label Explanation

[0462] 1A, 1B, 1C, 1D... Filters, 10... Substrate, 11... Support, 12... Resin film, 30... Dielectric multilayer film.

Claims

1. A filter having a substrate and a dielectric multilayer film, the dielectric multilayer film being stacked on at least one major surface side of the substrate and serving as the outermost layer, wherein, The substrate has a resin film comprising a pigment (I) and a resin, wherein the pigment (I) has a maximum absorption wavelength in dichloromethane in the range of 690 nm to 900 nm. The filter transmits visible light and light in at least a portion of the wavelength range of 900 nm to 1000 nm, and satisfies all of the following spectral characteristics (i-1) to (i-6): (i-1) In the spectral transmittance curve under the condition of 0 degrees incident angle, the maximum transmittance T in the wavelength range of 700 nm to 900 nm is... 700-900(0deg)MAX Below 7%; (i-2) In the spectral transmittance curve under the condition of an incident angle of 50 degrees, the maximum transmittance T in the wavelength range of 700 nm to 850 nm is... 700-850(50deg)MAX Less than 5%; (i-3) In the spectral transmittance curve under the condition of 0 degrees incident angle, within the wavelength range of 900 nm to 950 nm, the shortest wavelength with a transmittance of 10% is set as IR10. 900-950(0deg) Set the shortest wavelength with a transmittance of 70% to IR70. 900-950(0deg) , at this time, IR70 900-950(0deg) -IR10 900-950(0deg) Below 20nm; (i-4) In the spectral transmittance curve under the condition of an incident angle of 50 degrees, within the wavelength range of 850 nm to 930 nm, the shortest wavelength with a transmittance of 10% is set as IR10. 850-930(50deg) Set the shortest wavelength with a transmittance of 70% to IR70. 850-930(50deg) , at this time, IR70 850-930(50deg) -IR10 850-930(50deg) Below 50nm; (i-5) In the spectral transmittance curve under the condition of 0 degrees incident angle, the shortest wavelength with a transmittance of 50% is set as IR50 in the range above 850 nm. 850(0deg) In the spectral transmittance curve under an incident angle of 50 degrees, the shortest wavelength with a transmittance of 50% is set as IR50 in the range above 850 nm. 850(50deg) , at this time, IR50 850(0deg) With IR50 850(50deg) The absolute value of the difference is less than 30nm; (i-6) In the spectral transmittance curve under the condition of 0 degrees of incident angle, the average transmittance T in the wavelength range of 450 nm to 600 nm. 450-600(0deg)AVE It is over 60%.

2. The filter as described in claim 1, wherein, The filter also satisfies the following spectral characteristics (i-7): (i-7) In the spectral transmittance curve under the condition of 0 degrees incident angle, the average transmittance T in the wavelength range of 930 nm to 950 nm. 930-950(0deg)AVE It is over 70%.

3. The filter as described in claim 1 or 2, wherein, In the spectral characteristics (i-6), the average transmittance T 450-600(0deg)AVE It is over 75%.

4. The filter as described in claim 1 or 2, wherein, The resin film satisfies all of the following spectral characteristics (ii-1) to (ii-5): (ii-1) In the spectral transmittance curve, the average internal transmittance T in the wavelength range of 450 nm to 600 nm 450-600AVE It is over 80%; (ii-2) The wavelength IR50 when the internal transmittance is 50% is in the range of 620nm to 660nm; (ii-3) In the spectral transmittance curve, the average internal transmittance T in the wavelength range of 700 nm to 830 nm 700-830AVE Less than 5%; (ii-4) In the spectral transmittance curve, the maximum internal transmittance T in the wavelength range of 720 nm to 830 nm. 720-830MAX Less than 10%; (ii-5) Within the wavelength range of 850nm to 950nm, the minimum wavelength when the internal transmittance is 20% is set as IR20, and the minimum wavelength when the internal transmittance is 80% is set as IR80. at this time, The absolute value of the difference between IR20 and IR80 is less than 50nm.

5. The filter as described in claim 1 or 2, wherein, For the pigment (I), the following characteristic (iii-1) is satisfied in the spectral internal transmittance curve measured by dissolving the pigment (I) in the resin in such a way that the internal transmittance at the maximum absorption wavelength in the resin constituting the resin film is 10%: (iii-1) When the maximum absorption wavelength is set to D [nm] and the average internal transmittance in the range of 450nm to 600nm is set to E, E > 103.5 - (D / 100).

6. The filter as described in claim 1 or 2, wherein, The pigment (I) comprises compounds selected by choosing one or more from each of compounds (A), (B), and (C). The compound (A) has a maximum absorption wavelength in dichloromethane in the range of wavelengths greater than or equal to 690 nm and less than 735 nm. The compound (B) has a maximum absorption wavelength in dichloromethane in the range of wavelengths greater than or equal to 735 nm and less than 830 nm. The compound (C) has a maximum absorption wavelength in dichloromethane in the range of wavelengths greater than or equal to 830 nm and less than 900 nm.

7. The filter as claimed in claim 6, wherein, For the compound (C), the internal transmittance spectrum measured by dissolving the compound (C) in the resin constituting the resin film in such a way that the internal transmittance at the maximum absorption wavelength is 10% satisfies the following characteristic (iii-2): (iii-2) On the longer wavelength side of the maximum absorption wavelength, set the wavelength when the internal transmittance is 20% as IR20 and the wavelength when the internal transmittance is 80% as IR80. at this time, The absolute value of the difference between IR20 and IR80 is less than 50nm.

8. The filter as claimed in claim 6, wherein, Compounds (A), (B), and (C) are selected from squaric acid. Either a salt compound or anthocyanin compound.

9. The filter as described in claim 1 or 2, wherein, The transmittance curve of the dielectric multilayer film under the condition of incident angle of 0 degrees satisfies all of the following spectral characteristics (iv-1) to (iv-6): (iv-1) Average transmittance T in the wavelength range of 450 nm to 600 nm 450-600AVE It is over 93%; (iv-2) In the wavelength range of 600nm to 800nm, the wavelength VL50 with a transmittance of 50% is in the range of 680nm to 750nm; (iv-3) Average transmittance T in the wavelength range of 750 nm to 900 nm 750-900AVE Less than 10%; (iv-4) In the wavelength range of 850 nm to 950 nm, the wavelength IR50 with 50% transmittance. 850-950 Within the range of 900nm to 930nm; (iv-5) Average transmittance T in the wavelength range of 930 nm to 950 nm 930-950AVE It is over 80%; (iv-6) In the wavelength range of 950 nm to 1100 nm, the wavelength IR50 with 50% transmittance. 950-1100 Within the range of 1000nm to 1080nm.

10. The filter as claimed in claim 1 or 2, wherein, The substrate includes a support and the resin film, and the resin film is laminated on at least one main surface of the support.

11. The filter as claimed in claim 1 or 2, wherein, The resin is a polyimide resin.

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