KR102746819B1 - Optical filters, camera modules and electronic devices - Google Patents

Abstract

An object of the present invention is to provide an optical filter capable of suppressing color shading and ghosting of a camera image at a high level. The optical filter of the present invention satisfies requirements (a) and (b): (a) in a region of a wavelength of 430 to 580 nm, the minimum value T _b-0 of the transmittance of light incident from a vertical direction, the minimum value T _b-30 of the transmittance of light incident from a direction obliquely 30 degrees to the vertical direction, and the minimum value T _b-60 of the transmittance of light incident from a direction obliquely 60 degrees to the vertical direction are all 55% or more and less than 90%; (b) In a region of a wavelength of 700 to 780 nm, the average value OD _a-0 of the optical density for light incident from a vertical direction, the average value OD _a-30 of the optical density for light incident from a direction obliquely 30 degrees to the vertical direction, and the average value OD _a- 60 of the optical density for light incident from a direction obliquely 60 degrees to the vertical direction are all 1.8 or more.

Description

Optical filters, camera modules and electronic devices

The present invention relates to an optical filter, a camera module, and an electronic device. More specifically, the present invention relates to an optical filter having specific optical characteristics, a camera module using the optical filter, and an electronic device having the camera module.

Solid-state imaging devices such as video cameras, digital still cameras, and mobile phones with camera functions use solid-state imaging elements such as CCDs and CMOS image sensors for color images. These solid-state imaging elements use silicon photodiodes in their light-receiving sections that are sensitive to near-infrared rays that cannot be detected by the human eye. In these solid-state imaging elements, it is necessary to perform sensitivity correction to produce natural colors when viewed by the human eye, and so optical filters (e.g., near-infrared cut filters) that selectively transmit or cut light in a specific wavelength range are often used.

As such near-infrared cut filters, those manufactured by various methods have been used conventionally. For example, a near-infrared cut filter is known that uses a transparent resin as a base material and contains a near-infrared absorbing pigment in the transparent resin (see, for example, Patent Document 1). However, the near-infrared cut filter described in Patent Document 1 does not necessarily have sufficient near-infrared absorption characteristics in some cases.

In Patent Document 2, the applicant proposes a near-infrared cut filter having little change in optical properties even when the incident angle is changed and having high visible light transmittance by using a transparent resin substrate containing a near-infrared absorbing dye having an absorption maximum in a specific wavelength range. In addition, Patent Document 3 describes the purpose of obtaining a near-infrared cut filter that achieves both excellent visible light transmittance and a high level of long-wavelength absorption maximum, which were conventional problems, by using a phthalocyanine-based dye having a specific structure.

However, in the near-infrared cut filters described in Patent Documents 2 and 3, although the applied substrate has a sufficiently strong absorption band around 700 nm, it has almost no absorption in the near-infrared wavelength range such as, for example, 900 to 1200 nm. Therefore, light in the near-infrared wavelength range is cut almost only by reflection of the dielectric multilayer film, but in such a configuration, there were cases where a small amount of stray light due to internal reflection in the optical filter or reflection between the optical filter and the lens caused ghosting or flare when shooting in a dark environment. In particular, in recent years, there has been a strong demand for high image quality of cameras even in mobile devices such as smartphones, and there were cases where conventional optical filters could not be used suitably.

Meanwhile, as an optical filter using a substrate having a wide absorption in the near-infrared wavelength range, an infrared shielding filter such as Patent Document 4 has been proposed. In Patent Document 4, wide absorption in the near-infrared wavelength range is achieved mainly by applying a compound having a dithiolene structure, but the absorption intensity around 700 nm is not sufficient. In particular, when used under high incidence angle conditions (e.g., 45 degree incidence) accompanying the recent reduction in the magnification of camera modules, there have been cases where image deterioration due to color shading occurred.

In addition, Patent Document 5 discloses a near-infrared cut filter having a near-infrared absorbing glass substrate and a layer containing a near-infrared absorbing pigment, but there were cases where color shading could not be sufficiently improved even with the configuration described in Patent Document 5. For example, Fig. 5 of Patent Document 5 shows optical characteristic graphs at 0 degree incidence and at 30 degree incidence, but even at 30 degree incidence, a large wavelength shift is observed in the region (630 to 700 nm) below the visible light transmittance band.

Japanese Patent Publication No. 6-200113 Japanese Patent Publication No. 2011-100084 International Publication No. 2015/025779 Pamphlet International Publication No. 2014/168190 Pamphlet International Publication No. 2014/030628 Pamphlet

Along with the above-mentioned tasks, recently, with the aim of further improving the performance of camera modules, a novel module configuration that separates the functions of a conventional optical filter that combines absorption by a pigment and reflection by a dielectric multilayer film into a separate component has been examined, and an optical filter that can support such a configuration is also demanded.

The present invention aims to provide an optical filter capable of suppressing color shading and ghosting of camera images at a high level, which could not be sufficiently achieved with conventional optical filters.

As a result of careful examination to solve the above-mentioned problems, the present inventors have found that by using an optical filter in which, in a specific wavelength range, the minimum values of the transmittance of light incident from the vertical direction of the optical filter, the direction obliquely 30 degrees to the vertical direction, and the direction obliquely 60 degrees to the vertical direction are all within specific ranges, and further, in a specific wavelength range, the average values of the optical densities (OD values) for light incident from the vertical direction of the optical filter, the direction obliquely 30 degrees to the vertical direction, and the direction obliquely 60 degrees to the vertical direction are all within specific ranges, the targeted near-infrared cut characteristics, visible light transmittance, color shading suppression effect, and ghost suppression effect can be achieved, thereby completing the present invention. Examples of embodiments of the present invention are shown below.

[1] An optical filter satisfying the following requirements (a) and (b):

(a) In a region of a wavelength of 430 to 580 nm, the minimum value T _b-0 of the transmittance of light incident from a vertical direction of the optical filter, the minimum value T _b-30 of the transmittance of light incident from a direction obliquely 30 degrees to the vertical direction, and the minimum value T _b-60 of the transmittance of light incident from a direction obliquely 60 degrees to the vertical direction are all 55% or more and less than 90%;

(b) In a region of a wavelength of 700 to 780 nm, the average value OD _a-0 of the optical density for light incident from a direction perpendicular to the optical filter, the average value OD _a-30 of the optical density for light incident from a direction oblique to 30 degrees with respect to the vertical direction, and the average value OD _a-60 of the optical density for light incident from a direction oblique to 60 degrees with respect to the vertical direction are all 1.8 or more.

[2] An optical filter as described in item [1], which additionally satisfies the following requirement (c):

(c) In the range of wavelengths from 900 to 1,200 nm, the average value of the transmittance of light incident in the vertical direction of the optical filter, T _IR, is 60% or more.

[3] An optical filter as described in item [1] or [2], which additionally satisfies the following requirement (d):

(d) In a region of a wavelength of 430 to 580 nm, the average value T _a-0 of the transmittance of light incident from a vertical direction of the optical filter, the average value T _a-30 of the transmittance of light incident from a direction obliquely 30 degrees to the vertical direction, and the average value T _a-60 of the transmittance of light incident from a direction obliquely 60 degrees to the vertical direction are all 65% or more and less than 90%.

[4] An optical filter according to any one of items [1] to [3], comprising a substrate satisfying the following requirement (e):

(e) has a layer including a compound (A) having an absorption maximum in a wavelength range of 650 to 800 nm.

[5] An optical filter as described in item [4], which additionally satisfies the following requirement (f):

(f) The absolute value |X b - X a | of the difference between the wavelength X _a on the longest wavelength side, which has a transmittance for light incident from the vertical direction of the substrate of more than 10% and less than or equal to 10% from the short wavelength side to the long wavelength side, and the wavelength X _b on the shortest wavelength side, which has a transmittance for light incident from the vertical direction of the substrate of less than or equal to 10% and more than 10% from the short wavelength side to the _{long wavelength} side, is 100 nm or more.

[6] An optical filter according to item [4] or [5], characterized in that the compound (A) is at least one compound selected from the group consisting of squarylium compounds, phthalocyanine compounds, naphthalocyanine compounds, croconium compounds, and cyanine compounds.

[7] An optical filter according to any one of claims [4] to [6], characterized in that the above-described material contains, as the compound (A), a compound (A-a) having an absorption maximum in a range of a wavelength exceeding 715 nm and not more than 715 nm, a compound (A-b) having an absorption maximum in a range of a wavelength exceeding 715 nm and not more than 750 nm, and a compound (A-c) having an absorption maximum in a range of a wavelength exceeding 750 nm and not more than 800 nm.

[8] An optical filter according to any one of claims [4] to [7], wherein the layer containing the compound (A) is a transparent resin layer.

[9] An optical filter according to item [8], characterized in that the resin constituting the transparent resin layer is at least one resin selected from the group consisting of a cyclic polyolefin resin, an aromatic polyether resin, a polyimide resin, a fluorene polycarbonate resin, a fluorene polyester resin, a polycarbonate resin, a polyamide resin, an aramid resin, a polysulfone resin, a polyethersulfone resin, a polyparaphenylene resin, a polyamideimide resin, a polyethylene naphthalate resin, a fluorinated aromatic polymer resin, a (modified) acrylic resin, an epoxy resin, a silsesquioxane ultraviolet-curable resin, a maleimide resin, an alicyclic epoxy thermosetting resin, a polyether ether ketone resin, a polyarylate resin, an allyl ester curable resin, an acrylic ultraviolet-curable resin, a vinyl ultraviolet-curable resin, and a resin containing silica as a main component formed by a sol-gel method.

[10] An optical filter according to item [8] or [9], wherein the refractive index (n20d) of the resin constituting the transparent resin layer is 1.50 to 1.53.

[11] A camera module characterized by having an optical filter as described in any one of items [1] to [10].

[12] A camera module according to item [11], characterized in that it has a cover member that protects the internal mechanism of the camera module from the outside, and the cover member has a near-infrared reflection function.

[13] An electronic device characterized by having a camera module as described in [11].

According to the present invention, an optical filter having excellent near-infrared cut characteristics, low incident angle dependence, excellent transmittance characteristics in the visible light wavelength range, color shading suppression effect, and ghost suppression effect can be provided.

Figure 1 is a diagram showing a configuration for measuring a transmission spectrum from a vertical direction, a direction inclined at 30 degrees, and a direction inclined at 60 degrees.
Figure 2 is a schematic diagram showing the configuration of a camera module used for color shading evaluation in examples and comparative examples.
Figure 3 is a schematic diagram for explaining the color shading evaluation of camera images performed in examples and comparative examples.
Figure 4 is a schematic diagram for explaining the ghost evaluation of camera images performed in examples and comparative examples.
Figure 5 is a spectral transmittance spectrum of the optical filter obtained in Example 1.
Figure 6 is a spectral transmittance spectrum of the optical filter obtained in Example 2.
Figure 7 is a spectral transmittance spectrum of the optical filter obtained in Example 3.
Figure 8 is a spectral transmittance spectrum of the optical filter obtained in Example 4.
Figure 9 is a spectral transmittance spectrum of the optical filter obtained in Example 5.
Figure 10 is a spectral transmittance spectrum of the optical filter obtained in Example 6.
Figure 11 is a spectral transmittance spectrum of the optical filter obtained in Example 7.
Figure 12 is a spectral transmittance spectrum of the optical filter obtained in Example 8.
Figure 13 is a spectral transmittance spectrum of the optical filter obtained in Example 9.
Figure 14 is a spectral transmittance spectrum of the optical filter obtained in Example 10.
Figure 15 is a spectral transmittance spectrum of the optical filter obtained in Example 11.
Figure 16 is a spectral transmittance spectrum of the optical filter obtained in Example 15.
Figure 17 is a spectral transmittance spectrum of the optical filter obtained in Example 16.
Figure 18 is a spectral transmittance spectrum of the optical filter obtained in Comparative Example 1.
Figure 19 is a spectral transmittance spectrum of the optical filter obtained in Comparative Example 2.
Figure 20 is a spectral transmittance spectrum of the optical filter obtained in Comparative Example 3.
Figure 21 is a spectral transmittance spectrum of the optical filter obtained in Comparative Example 4.

Hereinafter, an optical filter according to the present invention, a camera module using the optical filter, and an electronic device having the camera module will be described in detail.

[Optical Filter]

The optical filter of the present invention is characterized by satisfying the following requirements (a) and (b), and preferably further satisfying the following requirements (c) and/or (d).

(a) In a region of a wavelength of 430 to 580 nm, the minimum value T _b-0 of the transmittance of light incident from a vertical direction of the optical filter, the minimum value T _b-30 of the transmittance of light incident from a direction oblique to 30 degrees with respect to the vertical direction, and the minimum value T _b-60 of the transmittance of light incident from a direction oblique to 60 degrees with respect to the vertical direction are all 55% or more and less than 90%.

(b) In a region of a wavelength of 700 to 780 nm, the average value OD _a-0 of the optical density for light incident from a direction perpendicular to the optical filter, the average value OD _a-30 of the optical density for light incident from a direction oblique to 30 degrees with respect to the vertical direction, and the average value OD _a-60 of the optical density for light incident from a direction oblique to 60 degrees with respect to the vertical direction are all 1.8 or more.

(c) In the range of wavelengths from 900 to 1,200 nm, the average value of the transmittance of light incident in the vertical direction of the optical filter, T _IR, is 60% or more.

(d) In a region of a wavelength of 430 to 580 nm, the average value T _a-0 of the transmittance of light incident from a vertical direction of the optical filter, the average value T _a-30 of the transmittance of light incident from a direction obliquely 30 degrees to the vertical direction, and the average value T _a-60 of the transmittance of light incident from a direction obliquely 60 degrees to the vertical direction are all 65% or more and less than 90%.

Below, each requirement is explained.

<Requirement (a)>

The above T _b-0 and the above T _b-30 are preferably 63% or more and 86% or less, more preferably 67% or more and 82% or less, and the above T _b-60 is preferably 58% or more and 80% or less, more preferably 60% or more and 75% or less.

As a method for satisfying requirement (a), i.e., a method for adjusting the minimum value of each transmittance, an example of which may be mentioned is a method of appropriately selecting and adjusting the type and addition amount of compound (A) described below so that the minimum value of the transmittance within the specified range is obtained.

By satisfying requirement (a), a high-quality camera image can be obtained because the change in RGB balance is small even at high-angle incidences such as 30 degrees or 60 degrees.

<Requirement (b)>

The above OD _a-0 and the above OD _a-30 are preferably 1.8 or more and 4.0 or less, more preferably 1.9 or more and 3.5 or less, and the above OD _a-60 is preferably 2.1 or more and 4.5 or less, more preferably 2.2 or more and 4.0 or less.

As a method for satisfying requirement (b), i.e., a method for adjusting the average value of the optical density (OD value), an example of which may be mentioned is a method of appropriately selecting and adjusting the type and amount of compound (A) described below so that an average value of the transmittance within a specified range is obtained.

By satisfying requirement (b), the optical filter can sufficiently cut not only near-infrared rays transmitted in the vertical direction but also near-infrared rays transmitted at a high angle of incidence, so that a camera image with no or reduced color shading can be obtained.

Here, the OD value is the common logarithm of the transmittance, and can be calculated by the following equation (1). If the average OD value in a specified wavelength range is high, the optical filter indicates that the light cut characteristic in that wavelength range is high.

Average OD value in a certain wavelength range = -Log ₁₀ (average transmittance in a certain wavelength range (%)/100)… Equation (1)

<Requirement (c)>

The above T _IR is preferably 70% to 98%, more preferably 80% to 95%, even more preferably 85% to 94%, and particularly preferably 89% to 93%.

As a method for satisfying requirement (c), i.e., a method for adjusting the average value of light transmittance, an example of which may be mentioned is a method of appropriately selecting and adjusting the type and addition amount of compound (A) described below so that a transmittance within a specified range is obtained.

By satisfying requirement (c), a camera image with reduced ghosting can be obtained because the transmittance in the near-infrared region is high and reflected light in the near-infrared region can be reduced.

<Requirement (d)>

The above T _a-0 is preferably 73% or more and 88% or less, more preferably 76% or more and 86% or less, the above T _a-30 is preferably 72% or more and 87% or less, more preferably 75% or more and 85% or less, and the above T _a-60 is preferably 68% or more and 85% or less, more preferably 70% or more and 80% or less.

As a method for satisfying requirement (d), i.e., a method for adjusting the average value of each transmittance, an example of which may be mentioned is a method of appropriately selecting and adjusting the type and addition amount of compound (A) described below so that an average value of the transmittance within the specified range is obtained.

By satisfying requirement (d), high-quality camera images can be obtained because the change in RGB balance is small even at high angles of incidence such as 30 degrees or 60 degrees.

<Thickness of optical filter>

The thickness of the optical filter of the present invention is preferably 210 µm or less, more preferably 190 µm or less, even more preferably 160 µm or less, and particularly preferably 130 µm or less, and the lower limit is not particularly limited, but is preferably 20 µm or more.

[write]

The composition of the optical filter of the present invention is not particularly limited as long as an optical filter exhibiting the optical characteristics described above is obtained, but it is preferable to include a substrate satisfying the following requirement (e), and it is preferable that the substrate further satisfy the following requirement (f).

(e) has a layer including a compound (A) having an absorption maximum in a wavelength range of 650 to 800 nm.

(f) The absolute value |X b - X a | of the difference between the wavelength X _a on the longest wavelength side, which has a transmittance for light incident from the vertical direction of the substrate of more than 10% and less than or equal to 10% from the short wavelength side to the long wavelength side, and the wavelength X _b on the shortest wavelength side, which has a transmittance for light incident from the vertical direction of the substrate of less than or equal to 10% and more than 10% from the short wavelength side to the _{long wavelength} side, is 100 nm or more.

Below, each requirement is explained.

<Requirement (e)>

In the requirement (e), the component constituting the layer including the compound (A) is not particularly limited, but examples thereof include a transparent resin, a sol-gel material, a low-temperature curing glass material, etc., but from the viewpoint of ease of handling and compatibility with the compound (A), a transparent resin is preferable.

The above description may be a single layer or a multilayer, as long as it has a layer containing the compound (A).

<Requirement (f)>

The difference |X _b -X _a | between the wavelengths X _a and X _b is preferably 110 nm or more, more preferably 115 nm or more, even more preferably 120 nm or more, and particularly preferably 125 nm or more. The upper limit is not particularly limited, but depending on the characteristics of the compound (A) or other near-infrared absorbers, if the value is too large, the visible light transmittance may decrease, so that, for example, it is preferably 300 nm or less. When the difference |X _b -X _a | is in the above range, an absorption band of sufficient intensity (width) is provided in a near-infrared wavelength range close to the visible light range, and color shading can be suppressed even under conditions where the incident angle is large, such as an incident angle of 30 degrees or 60 degrees, so that is preferable.

The wavelength value (X _a + X _b )/2 corresponding to the middle of X _a and X _b can be said to be the center wavelength of the absorption band in the near-infrared wavelength range close to the visible light range, and is preferably 650 nm or more and 850 nm or less, more preferably 680 nm or more and 820 nm or less, and even more preferably 700 nm or more and 800 nm or less. When the wavelength value represented by (X _a + X _b )/2 is within the above range, light in the wavelength range near the long wavelength end of the visible light range can be cut more efficiently, which is preferable.

The above X _a is preferably a wavelength of 610 nm to 720 nm, more preferably a wavelength of 625 nm to 710 nm, and even more preferably a wavelength of 630 nm to 700 nm. When X _a is in this range, it is preferable because a camera image with less noise and excellent color reproducibility tends to be obtained.

<Thickness of material>

The thickness of the substrate can be appropriately selected depending on the intended use and is not particularly limited, but is preferably 10 to 200 μm, more preferably 20 to 180 μm, and even more preferably 25 to 150 μm. When the thickness of the substrate is within the above range, an optical filter using the substrate can be made thinner and lighter, so that it can be suitably used for various uses such as solid-state imaging devices. In particular, when the substrate including the transparent resin substrate is used in a lens unit such as a camera module, it is preferable because a lower magnification and lighter weight of the lens unit can be realized.

≪Compound (A)≫

The compound (A) is not particularly limited as long as it has an absorption maximum in the range of 650 to 800 nm in wavelength, but is preferably at least one compound selected from the group consisting of squarylium compounds, phthalocyanine compounds, naphthalocyanine compounds, croconium compounds, and cyanine compounds, and particularly preferably squarylium compounds, phthalocyanine compounds, and cyanine compounds. In addition, the compound (A) may be used alone or in combination of two or more.

Squarylium compounds have excellent visible light transmittance, steep absorption characteristics, and high molar extinction coefficients, but sometimes generate fluorescence that causes scattered light when light is absorbed. In such cases, by combining a squarylium compound with another compound (A), an optical filter with less scattered light and better camera image quality can be obtained.

The maximum absorption wavelength of compound (A) is preferably 660 nm or more and 795 nm or less, more preferably 680 nm or more and 790 nm or less.

The compound (A) is not particularly limited as long as it has an absorption maximum in a range of wavelengths 650 to 800 nm, but from the viewpoint of the heat resistance of the optical filter, it is more preferable to include at least one each of a compound (A-a) having an absorption maximum in a range of wavelengths 650 nm to 715 nm, a compound (A-b) having an absorption maximum in a range of wavelengths exceeding 715 nm to 750 nm, and a compound (A-c) having an absorption maximum in a range of wavelengths exceeding 750 nm to 800 nm. When the compound (A) has such a composition, not only can the near-infrared absorption band be efficiently widened while minimizing the decrease in visible light transmittance, but also there is a tendency for heat resistance and weather resistance to be improved by intermolecular interaction between the compounds (As), which is preferable.

When compound (A) is a combination of two or more compounds, the difference in the maximum absorption wavelength between the compound (A) having the shortest maximum absorption wavelength and the compound (A) having the longest maximum absorption wavelength to be applied is preferably 20 to 100 nm, more preferably 30 to 90 nm, and even more preferably 40 to 80 nm. When the difference in the maximum absorption wavelength is within the above range, scattered light due to fluorescence can be sufficiently reduced, and a wide absorption band around 700 nm and excellent visible light transmittance can both be achieved, which is preferable.

The total content of the compound (A), when using a substrate including a transparent resin substrate containing the compound (A), for example, or a substrate in which a resin layer such as an overcoat layer containing a curable resin or the like is laminated on a transparent resin substrate containing the compound (A), is preferably 0.04 to 2.0 parts by mass, more preferably 0.06 to 1.5 parts by mass, and even more preferably 0.08 to 1.0 parts by mass, relative to 100 parts by mass of the transparent resin. When using a substrate in which a transparent resin layer such as an overcoat layer containing a curable resin or the like containing the compound (A) is laminated on a support such as a glass support or a base resin support, as the substrate, is preferably 0.4 to 5.0 parts by mass, more preferably 0.6 to 4.0 parts by mass, and even more preferably 0.8 to 3.5 parts by mass, relative to 100 parts by mass of the resin forming the transparent resin layer containing the compound (A).

(squarylium compounds)

The above squarylium compound is not particularly limited, but at least one compound selected from the group consisting of a squarylium compound represented by the following formula (I) and a squarylium compound represented by the following formula (II) is preferable. Hereinafter, they are also referred to as “compound (I)” and “compound (II)”, respectively.

In formula (I), R ^a , R ^b and Ya satisfy the following conditions (α) or (β).

Condition (α):

Each of the plurality of R ^a independently represents a hydrogen atom, a halogen atom, a sulfo group, a hydroxyl group, a cyano group, a nitro group, a carboxyl group, a phosphate group, -L ¹ or -NR ^e R ^f group;

Each of the plurality of R ^b independently represents a hydrogen atom, a halogen atom, a sulfo group, a hydroxyl group, a cyano group, a nitro group, a carboxyl group, a phosphate group, -L ¹ or -NR ^g R ^h group;

Plural Ya each independently represent a -NR ^j R ^k group;

L ¹ represents L ^a , L ^b , L ^c , L ^d , L ^e , L ^f , L ^g or L ^h ;

R ^e and R ^f each independently represent a hydrogen atom, -L ^a , -L ^b , -L ^c , -L ^d or -L ^e ;

R ^g and R ^h each independently represent a hydrogen atom, -L ^a , -L ^b , -L ^c , -L ^d , -L ^e or -C(O)R ⁱ group (R ⁱ represents -L ^a , -L ^b , -L ^c , -L ^d or -L ^e );

R ^j and R ^k each independently represent a hydrogen atom, -L ^a , -L ^b , -L ^c , -L ^d or -L ^e ;

L ^a represents an aliphatic hydrocarbon group having 1 to 12 carbon atoms which may have a substituent L;

L ^b represents a halogen-substituted alkyl group having 1 to 12 carbon atoms which may have a substituent L;

L ^c represents an alicyclic hydrocarbon group having 3 to 14 carbon atoms which may have a substituent L;

L ^d represents an aromatic hydrocarbon group having 6 to 14 carbon atoms which may have a substituent L;

L ^e represents a heterocyclic group having 3 to 14 carbon atoms which may have a substituent L;

L ^f represents an alkoxy group having 1 to 9 carbon atoms which may have a substituent L;

L ^g represents an acyl group having 1 to 9 carbon atoms which may have a substituent L;

L ^h represents an alkoxycarbonyl group having 1 to 9 carbon atoms which may have a substituent L;

L represents at least one substituent selected from the group consisting of an aliphatic hydrocarbon group having 1 to 12 carbon atoms, a halogen-substituted alkyl group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 14 carbon atoms, an aromatic hydrocarbon group having 6 to 14 carbon atoms, a heterocyclic group having 3 to 14 carbon atoms, a halogen atom, a sulfo group, a hydroxyl group, a cyano group, a nitro group, a carboxyl group, a phosphoric acid group, and an amino group.

Condition (β):

At least one of two R ^a on a benzene ring is bonded to Y on the same benzene ring to form a heterocycle having 5 or 6 atoms and containing at least one nitrogen atom;

The above heterocycle may have a substituent, and R ^b and R ^a which are not involved in the formation of the above heterocycle each independently have the same meaning as R ^b and R ^a of the above condition (α).

The above L ^a to L ^h preferably have a total number of carbon atoms including substituents of 50 or less, more preferably 40 or less, and particularly preferably 30 or less. If the number of carbon atoms is greater than this range, synthesis of the compound may become difficult, and the light absorption intensity per unit mass tends to decrease.

As the aliphatic hydrocarbon group having 1 to 12 carbon atoms in the above L ^a and L , examples thereof include alkyl groups such as a methyl group (Me), an ethyl group (Et), an n-propyl group (n-Pr), an isopropyl group (i-Pr), an n-butyl group (n-Bu), a sec-butyl group (s-Bu), a tert-butyl group (t-Bu), a pentyl group, a hexyl group, an octyl group, a nonyl group, a decyl group, and a dodecyl group; alkenyl groups such as a vinyl group, a 1-propenyl group, a 2-propenyl group, a butenyl group, a 1,3-butadienyl group, a 2-methyl-1-propenyl group, a 2-pentenyl group, a hexenyl group, and an octenyl group; and alkynyl groups such as an ethynyl group, a propynyl group, a butynyl group, a 2-methyl-1-propynyl group, a hexynyl group, and an octynyl group.

As the halogen-substituted alkyl group having 1 to 12 carbon atoms in the above L ^b and L, examples thereof include a trichloromethyl group, a trifluoromethyl group, a 1,1-dichloroethyl group, a pentachloroethyl group, a pentafluoroethyl group, a heptachloropropyl group, and a heptafluoropropyl group.

As the alicyclic hydrocarbon group having 3 to 14 carbon atoms in the above L ^c and L, examples thereof include cycloalkyl groups such as a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group; and polycyclic alicyclic groups such as a norbornane group and an adamantane group.

As the aromatic hydrocarbon group having 6 to 14 carbon atoms in the above L ^d and L, examples thereof include a phenyl group, a tolyl group, a xylyl group, a mesityl group, a cumenyl group, a 1-naphthyl group, a 2-naphthyl group, an anthracenyl group, a phenanthryl group, an acenaphthyl group, a phenalenyl group, a tetrahydronaphthyl group, an indanyl group, and a biphenylyl group.

As the heterocyclic group having 3 to 14 carbon atoms in the above L ^e and L, examples thereof include groups including heterocycles such as furan, thiophene, pyrrole, pyrazole, imidazole, triazole, oxazole, oxadiazole, thiazole, thiadiazole, indole, indoline, indolenine, benzofuran, benzothiophene, carbazole, dibenzofuran, dibenzothiophene, pyridine, pyrimidine, pyrazine, pyridazine, quinoline, isoquinoline, acridine, morpholine, and phenazine.

Examples of the alkoxy group having 1 to 12 carbon atoms in the above L ^f include a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, and an octyloxy group.

As the acyl group having 1 to 9 carbon atoms in the above L ^g , examples thereof include an acetyl group, a propionyl group, a butyryl group, an isobutyryl group, a valeryl group, an isovaleryl group, and a benzoyl group.

Examples of the alkoxycarbonyl group having 1 to 9 carbon atoms in the above L ^h include a methoxycarbonyl group, an ethoxycarbonyl group, a propoxycarbonyl group, an isopropoxycarbonyl group, a butoxycarbonyl group, a pentyloxycarbonyl group, a hexyloxycarbonyl group, and an octyloxycarbonyl group.

As the above L ^a , preferably, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a hexyl group, an octyl group, a 4-phenylbutyl group, and 2-cyclohexylethyl are selected, and more preferably, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, and a tert-butyl group.

As the above L ^b , preferably, a trichloromethyl group, a pentachloroethyl group, a trifluoromethyl group, a pentafluoroethyl group, or a 5-cyclohexyl-2,2,3,3-tetrafluoropentyl group is used, and more preferably, a trichloromethyl group, a pentachloroethyl group, a trifluoromethyl group, or a pentafluoroethyl group is used.

As the above L ^c , a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a 4-ethylcyclohexyl group, a cyclooctyl group, or a 4-phenylcycloheptyl group is preferably used, and a cyclopentyl group, a cyclohexyl group, or a 4-ethylcyclohexyl group is more preferably used.

As the above L ^d , preferably, a phenyl group, a 1-naphthyl group, a 2-naphthyl group, a tolyl group, a xylyl group, a mesityl group, a cumenyl group, a 3,5-di-tert-butylphenyl group, a 4-cyclopentylphenyl group, a 2,3,6-triphenylphenyl group, a 2,3,4,5,6-pentaphenylphenyl group are included, and more preferably, a phenyl group, a tolyl group, a xylyl group, a mesityl group, a cumenyl group, or a 2,3,4,5,6-pentaphenylphenyl group are included.

As the above L ^e, it is preferably a group containing furan, thiophene, pyrrole, indole, indoline, indolenine, benzofuran, benzothiophene, and morpholine, and more preferably a group containing furan, thiophene, pyrrole, and morpholine.

As the above L ^f , preferably, a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, a methoxymethyl group, a methoxyethyl group, a 2-phenylethoxy group, a 3-cyclohexylpropoxy group, a pentyloxy group, a hexyloxy group, an octyloxy group, and more preferably, a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group.

As the above L ^g , an acetyl group, a propionyl group, a butyryl group, an isobutyryl group, a benzoyl group, a 4-propylbenzoyl group, a trifluoromethylcarbonyl group is preferable, and an acetyl group, a propionyl group, a benzoyl group is more preferable.

As the above L ^h , preferably, a methoxycarbonyl group, an ethoxycarbonyl group, a propoxycarbonyl group, an isopropoxycarbonyl group, a butoxycarbonyl group, a 2-trifluoromethylethoxycarbonyl group, a 2-phenylethoxycarbonyl group, and more preferably, a methoxycarbonyl group or an ethoxycarbonyl group.

The above L ^a to L ^h may additionally have at least one atom or group selected from the group consisting of a halogen atom, a sulfo group, a hydroxyl group, a cyano group, a nitro group, a carboxyl group, a phosphoric acid group, and an amino group. Examples of such groups include a 4-sulfobutyl group, a 4-cyanobutyl group, a 5-carboxypentyl group, a 5-aminopentyl group, a 3-hydroxypropyl group, a 2-phosphorylethyl group, a 6-amino-2,2-dichlorohexyl group, a 2-chloro-4-hydroxybutyl group, a 2-cyanocyclobutyl group, a 3-hydroxycyclopentyl group, a 3-carboxycyclopentyl group, a 4-aminocyclohexyl group, a 4-hydroxycyclohexyl group, a 4-hydroxyphenyl group, a pentafluorophenyl group, a 2-hydroxynaphthyl group, a 4-aminophenyl group, a 4-nitrophenyl group, a group containing 3-methylpyrrole, a 2-hydroxyethoxy group, a 3-cyanopropoxy group, a 4-fluorobenzoyl group, Examples include 2-hydroxyethoxycarbonyl group and 4-cyanobutoxycarbonyl group.

In the above condition (α), R ^a is preferably a hydrogen atom, a chlorine atom, a fluorine atom, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, a cyclohexyl group, a phenyl group, a hydroxyl group, an amino group, a dimethylamino group, or a nitro group, and more preferably a hydrogen atom, a chlorine atom, a fluorine atom, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, or a hydroxyl group.

In the above condition (α), R ^b is preferably a hydrogen atom, a chlorine atom, a fluorine atom, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, a cyclohexyl group, a phenyl group, a hydroxyl group, an amino group, a dimethylamino group, a cyano group, a nitro group, an acetylamino group, a propionylamino group, an N-methylacetylamino group, a trifluoromethanoylamino group, a pentafluoroethanoylamino group, a t-butanoylamino group, a cyclohexinoylamino group, and more preferably a hydrogen atom, a chlorine atom, a fluorine atom, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, a hydroxyl group, a dimethylamino group, a nitro group, an acetylamino group, a propionylamino group, a trifluoromethanoylamino group, a pentafluoroethanoylamino group, a t-butanoylamino group. It is a cyclohexinoylamino group.

As the above Ya, preferably, an amino group, a methylamino group, a dimethylamino group, a diethylamino group, a di-n-propylamino group, a diisopropylamino group, a di-n-butylamino group, a di-t-butylamino group, an N-ethyl-N-methylamino group, an N-cyclohexyl-N-methylamino group are selected, and more preferably, a dimethylamino group, a diethylamino group, a di-n-propylamino group, a diisopropylamino group, a di-n-butylamino group, and a di-t-butylamino group are selected.

In the condition (β) of the above formula (I), examples of the heterocycle having 5 or 6 constituent atoms and containing at least one nitrogen atom, wherein at least one of two R ^a on one benzene ring is bonded to Y on the same benzene ring, include pyrrolidine, pyrrole, imidazole, pyrazole, piperidine, pyridine, piperazine, pyridazine, pyrimidine, and pyrazine. Among these heterocycles, a heterocycle constituting the heterocycle and wherein one adjacent atom of a carbon atom constituting the benzene ring is a nitrogen atom is preferable, and pyrrolidine is more preferable.

In formula (II), X independently represents O, S, Se, NR ^c or C(R ^d R ^d ); a plurality of R ^c each independently represent a hydrogen atom, L ^a , L ^b , L ^c , L ^d or L ^e ; a plurality of R ^d each independently represent a hydrogen atom, a halogen atom, a sulfo group, a hydroxyl group, a cyano group, a nitro group, a carboxyl group, a phosphate group, a -L ¹ or a -NR ^e R ^f group, and adjacent R ^d groups may be connected to form a ring which may have a substituent; L ^a to L ^e , L ¹ , R ^e and R ^f have the same meanings as L ^a to L ^e , L ¹ , R ^e and R ^f defined in the formula (I).

In the above formula (II), R ^c is preferably a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, an n-hexyl group, a cyclohexyl group, a phenyl group, a trifluoromethyl group, or a pentafluoroethyl group, and more preferably a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, or an isopropyl group.

In the above formula (II), R ^d is preferably a hydrogen atom, a chlorine atom, a fluorine atom, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, an n-hexyl group, a cyclohexyl group, a phenyl group, a methoxy group, a trifluoromethyl group, a pentafluoroethyl group, or a 4-aminocyclohexyl group, and more preferably a hydrogen atom, a chlorine atom, a fluorine atom, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, a trifluoromethyl group, or a pentafluoroethyl group.

The above X is preferably O, S, Se, N-Me, N-Et, CH ₂ , C-Me ₂ , C-Et ₂ , and more preferably S, C-Me ₂ , C-Et ₂ .

In the above formula (II), adjacent R ^d may be connected to form a ring. Examples of such rings include a benzoindolene ring, an α-naphthoimidazole ring, a β-naphthoimidazole ring, an α-naphthoxazole ring, a β-naphthoxazole ring, an α-naphthothiazole ring, a β-naphthothiadiazole ring, an α-naphthoselenazole ring, and a β-naphthoselenazole ring.

In addition to the description methods such as the following formula (I-1) and the following formula (II-1), the structures of compound (I) and compound (II) can also be represented by a description method that takes a resonance structure such as the following formula (I-2) and the following formula (II-2). That is, the difference between the following formula (I-1) and the following formula (I-2) and the difference between the following formula (II-1) and the following formula (II-2) is only the description method of the structure, and they both represent the same compound. In the present invention, unless otherwise specified, the structure of a squarylium-based compound is represented by a description method such as the following formula (I-1) and the following formula (II-1).

Additionally, for example, a compound represented by the following formula (I-3) and a compound represented by the following formula (I-4) can be considered as the same compound.

The above compounds (I) and (II) are not particularly limited in structure as long as they satisfy the requirements of formulas (I) and (II), respectively. For example, in the case where the structures are represented as in formulas (I-1) and (II-1), the left and right substituents bonded to the central 4-membered ring may be the same or different, but the same ones are preferable because they are easier to synthesize.

Specific examples of the compounds (I) and (II) include compounds (a-1) to (a-36) described in Tables 1 to 3 below, which have a basic skeleton represented by formulae (I-A) to (I-H).

[표 1]

[Table 1]

[Table 2]

[Table 3]

The above compounds (I) and (II) can be synthesized by generally known methods, and can be synthesized by referring to methods described in, for example, Japanese Patent Application Laid-Open No. 1-228960, Japanese Patent Application Laid-Open No. 2001-40234, Japanese Patent No. 3196383, etc.

(Phthalocyanine compounds)

The above phthalocyanine compound is not particularly limited, but is preferably a compound represented by the following formula (III) (hereinafter also referred to as “compound (III)”).

In formula (III), M represents a substituted metal atom containing two hydrogen atoms, two monovalent metal atoms, a divalent metal atom, or a trivalent or tetravalent metal atom, and a plurality of R _a , R _b , R _c and R _d each independently represent at least one group selected from the group consisting of a hydrogen atom, a halogen atom, a hydroxyl group, a carboxyl group, a nitro group, an amino group, an amide group, an imide group, a cyano group, a silyl group, -L ¹ , -SL ² , -SS-L ² , -SO ₂ -L ³ , -N=NL ⁴ , or a group represented by the following formulas (A) to (H) to which at least one combination of R _a and _{R b} , R b and R _c and R _c and R _d is bonded. However, at least one of R _a , R _b , R _c and R _d bonded to the same aromatic ring is not a hydrogen atom.

The above amino group, amide group, imide group and silyl group may have a substituent L defined in the above formula (I),

L ¹ has the same meaning as L ¹ defined in the above formula (I),

L ² represents a hydrogen atom or any one of L ^a to L ^e defined in the above formula (I),

L ³ represents a hydroxyl group or any one of L ^a to L ^e ,

L ⁴ represents any one of the above L ^a to L ^e .

In formulas (A) to (H), R _x and R _y represent a carbon atom, and plural R _A to R _L each independently represent a hydrogen atom, a halogen atom, a hydroxyl group, a nitro group, an amino group, an amide group, an imide group, a cyano group, a silyl group, -L ¹ , -SL ² , -SS-L ² , -SO ₂ -L ³ , -N=NL ⁴ , and the amino group, the amide group, the imide group and the silyl group may have a substituent L defined in the formula (I), and L ¹ to L ⁴ have the same meaning as L ¹ to L ⁴ defined in the formula (III).

As amino groups that may have a substituent L in the above R _a to R _d and R _A to R _L , examples thereof include an amino group, an ethylamino group, a dimethylamino group, a methylethylamino group, a dibutylamino group, and a diisopropylamino group.

As the amide group which may have a substituent L in the above R _a to R _d and R _A to R _L, examples thereof include an amide group, a methylamide group, a dimethylamide group, a diethylamide group, a dipropylamide group, a diisopropylamide group, a dibutylamide group, an α-lactam group, a β-lactam group, a γ-lactam group, and a δ-lactam group.

As the imide group that may have a substituent L in the above R _a to R _d and R _A to R _L , examples thereof include an imide group, a methylimide group, an ethylimide group, a diethylimide group, a dipropylimide group, a diisopropylimide group, and a dibutylimide group.

As silyl groups that may have a substituent L in the above R _a to R _d and R _A to R _L , examples thereof include a trimethylsilyl group, a tert-butyldimethylsilyl group, a triphenylsilyl group, and a triethylsilyl group.

Examples of -SL ² in the above R _a to R _d and R _A to R _L include a thiol group, a methyl sulfide group, an ethyl sulfide group, a propyl sulfide group, a butyl sulfide group, an isobutyl sulfide group, a sec-butyl sulfide group, a tert-butyl sulfide group, a phenyl sulfide group, a 2,6-di-tert-butylphenyl sulfide group, a 2,6-diphenylphenyl sulfide group, and a 4-cumylphenyl sulfide group.

Examples of -SS-L ² in the above R _a to R _d and R _A to R _L include a disulfide group, a methyl disulfide group, an ethyl disulfide group, a propyl disulfide group, a butyl disulfide group, an isobutyl disulfide group, a sec-butyl disulfide group, a tert-butyl disulfide group, a phenyl disulfide group, a 2,6-di-tert-butylphenyl disulfide group, a 2,6-diphenylphenyl disulfide group, and a 4-cumylphenyl disulfide group.

In the above R _a to R _d and R _A to R _L , -SO ₂ -L ³ may be exemplified by a sulfo group, a mesyl group, an ethylsulfonyl group, an n-butylsulfonyl group, a p-toluenesulfonyl group, etc.

In the above R _a to R _d and R _A to R _L , -N=NL ⁴ may be exemplified by a methylazo group, a phenylazo group, a p-methylphenylazo group, a p-dimethylaminophenylazo group, etc.

As monovalent metal atoms in the above M, Li, Na, K, Rb, Cs, etc. can be mentioned.

As divalent metal atoms in the above M, examples thereof include Be, Mg, Ca, Ba, Ti, Cr, Mn, Fe, Ru, Co, Rh, Ni, Pd, Pt, Cu, Zn, Cd, Hg, Sn, Pb, etc.

As the substituted metal atom containing a trivalent metal atom in the above M, examples thereof include Al-F, Al-Cl, Al-Br, Al-I, Ga-F, Ga-Cl, Ga-Br, Ga-I, In-F, In-Cl, In-Br, In-I, Tl-F, Tl-Cl, Tl-Br, Tl-I, Fe-Cl, Ru-Cl, Mn-OH, etc.

In the above M, as a substituted metal atom containing a tetravalent metal atom, TiF ₂ , TiCl ₂ , TiBr ₂ , TiI ₂ , ZrCl ₂ , HfCl ₂ , CrCl ₂ , SiF ₂ , SiCl ₂ , SiBr ₂ , SiI ₂ , GeF ₂ , GeCl ₂ , GeBr ₂ , GeI ₂ , SnF ₂ , SnCl ₂ , SnBr ₂ , SnI ₂ , Zr(OH) ₂ , Hf(OH) ₂ , Mn(OH) ₂ , Si(OH) ₂ , Ge(OH) ₂ , Sn(OH) ₂ , TiR ₂ , CrR ₂ , SiR ₂ , GeR ₂ , SnR ₂ , Ti(OR) ₂ , Cr(OR) ₂ , Si(OR) ₂ , Ge(OR) ₂ , Sn(OR) ₂ (R represents an aliphatic group or an aromatic group), TiO, VO, MnO, etc.

As the above M, it is preferable that it is a divalent transition metal, a trivalent or tetravalent metal halide, or a tetravalent metal oxide belonging to group 5 to 11 of the periodic table, or further, period 4 to 5, and among them, Cu, Ni, Co, and VO are particularly preferable in terms of being able to achieve high visible light transmittance and stability.

The above phthalocyanine compound is generally known to be synthesized by a method of cyclization reaction of a phthalonitrile derivative as shown in the following formula (V), but the obtained phthalocyanine compound is a mixture of four isomers as shown in the following formulas (VI-1) to (VI-4). In the present invention, unless otherwise specified, only one isomer is exemplified for one phthalocyanine compound, but the other three isomers can be used in the same manner. In addition, these isomers can be used separately as needed, but the present invention handles the mixture of isomers collectively.

Specific examples of the above compounds (III) include compounds (b-1) to (b-56) described in Tables 4 to 7 below, which have a basic skeleton represented by formulae (III-A) to (III-J).

[Table 4]

[Table 5]

[Table 6]

[Table 7]

Compound (III) can be synthesized by a generally known method, for example, by referring to the method described in Japanese Patent No. 4081149 or “Phthalocyanine - Chemistry and Function -” (IPC, 1997).

(Cyanine compounds)

The above cyanine compound is not particularly limited, but is preferably a compound represented by any one of the following formulas (IV-1) to (IV-3) (hereinafter also referred to as “compounds (IV-1) to (IV-3)”).

In formulas (IV-1) to (IV-3), X _a ^- represents a monovalent anion, plural Ds independently represent a carbon atom, a nitrogen atom, an oxygen atom, or a sulfur atom, plural R _a , R _b , R _c , R _{d , R e , R f , R g , R h and R i are each} independently a hydrogen atom, a halogen atom, a hydroxyl group, a carboxyl group, a nitro group, an amino group, an amide group, an imide group, a cyano group, a silyl group, -L ¹ , -SL ² , -SS-L ³ , -SO ₂ -L ³ , -N=NL ⁴ , or at least one selected from the group consisting of groups represented by the formulas ₍ A) to (H) in which at least one combination of _{R b} and R _c , R _d and R _e , R _e and R f , R f and R _g , R _g and R _h and R _h and R _i is bonded. represents a group, and the amino group, amide group, imide group and silyl group may have a substituent L defined in the above formula (I),

L ¹ has the same meaning as L ¹ defined in the above formula (I),

L ² represents a hydrogen atom or any one of L ^a to L ^e defined in the above formula (I),

L ³ represents a hydrogen atom or any one of L ^a to L ^e ,

L ⁴ represents any one of the above L ^a to L ^e ,

Z _a to Z _c and Y _a to Y _d are each independently a hydrogen atom, a halogen atom, a hydroxyl group, a carboxyl group, a nitro group, an amino group, an amide group, an imide group, a cyano group, a silyl group, -L ¹ , -SL ² , -SS-L ² , -SO ₂ -L ³ , -N=NL ⁴ (L ¹ to L ⁴ have the same meaning as L ¹ to L ⁴ in the above R _a to R _i ), or an aromatic hydrocarbon group having 6 to 14 carbon atoms formed by bonding Z or Y selected from two adjacent ones thereof; an alicyclic hydrocarbon group having a 5 to 6 membered ring which may include at least one nitrogen atom, an oxygen atom, or a sulfur atom; Alternatively, it represents a heteroaromatic hydrocarbon group having 3 to 14 carbon atoms and containing at least one nitrogen atom, oxygen atom or sulfur atom, and these aromatic hydrocarbon groups, alicyclic hydrocarbon groups and heteroaromatic hydrocarbon groups may have an aliphatic hydrocarbon group having 1 to 9 carbon atoms or a halogen atom.

As an aromatic hydrocarbon group having 6 to 14 carbon atoms formed by combining Z or Y among the above Z _a to Z _c and Y _a to Y _d , examples thereof include compounds exemplified as aromatic hydrocarbon groups in the above substituent L.

As the alicyclic hydrocarbon group of 5 to 6 membered rings that may contain at least one nitrogen atom, oxygen atom or sulfur atom formed by combining Z or Y in the above Z _a to Z _c and Y _a to Y _d , examples thereof include compounds exemplified in the alicyclic hydrocarbon group and heterocycle in the above substituent L (excluding heteroaromatic hydrocarbon groups).

As a heteroaromatic hydrocarbon group having 3 to 14 carbon atoms formed by combining Z or Y in the above Z _a to Z _c and Y _a to Y _d , examples thereof include compounds exemplified as heterocyclic groups in the above substituent L (excluding alicyclic hydrocarbon groups containing at least one nitrogen atom, oxygen atom or sulfur atom).

In the above formulas (IV-1) to (IV-3), examples of the amino group, amide group, imide group, and silyl group that may have -SL ² , -SS-L ² , -SO ₂ -L ³ , -N=NL ⁴ , and the substituent L include groups similar to the groups exemplified in the above formula (III).

X _a ^- is not particularly limited as long as it is a monovalent anion, but examples thereof include I ^- , Br ^- , PF ₆ ^- , N(SO ₂ CF ₃ ) ₂ ^- , B(C ₆ F ₅ ) ₄ ^- , nickel dithiolate complexes, and copper dithiolate complexes.

Specific examples of the above compounds (IV-1) to (IV-3) include (c-1) to (c-24) described in Table 8 below.

[Table 8]

The above compounds (IV-1) to (IV-3) can be synthesized by generally known methods, for example, by the method described in Japanese Patent Application Laid-Open No. 2009-108267.

<Transparent Resin>

The transparent resin is not particularly limited as long as it does not impair the effects of the present invention, but for example, in order to secure thermal stability and formability into a film, a resin having a glass transition temperature (Tg) of preferably 110 to 380°C, more preferably 110 to 370°C, and even more preferably 120 to 360°C may be mentioned. In addition, in order to be suitable for a reflow process, the glass transition temperature of the resin is preferably 140°C or higher, and more preferably 230°C or higher.

It is particularly preferable that the refractive index (n20d) of the above transparent resin is 1.53 or less. A transparent resin having a refractive index (n20d) exceeding 1.53 tends to have many aromatic rings in its molecules, but in the resin of the structure, the interaction with the π conjugated system in the compound (A) molecule is too strong, which sometimes worsens the weather resistance.

As a transparent resin, when a 0.1 mm thick resin plate including the resin is formed, a resin having a total light transmittance (JIS K7105) of preferably 75 to 95%, more preferably 78 to 95%, and particularly preferably 80 to 95% of the resin plate can be used. When a resin having a total light transmittance within this range is used, the resulting substrate exhibits good transparency as an optical film.

The mass average molecular weight (Mw) of the transparent resin, as measured by gel permeation chromatography (GPC) method and converted to polystyrene, is usually 15,000 to 350,000, preferably 30,000 to 250,000, and the number average molecular weight (Mn) is usually 10,000 to 150,000, preferably 20,000 to 100,000.

Examples of the transparent resin include cyclic polyolefin resins, aromatic polyether resins, polyimide resins, fluorene polycarbonate resins, fluorene polyester resins, polycarbonate resins, polyamide resins, aramid resins, polysulfone resins, polyethersulfone resins, polyparaphenylene resins, polyamideimide resins, polyethylene naphthalate resins, fluorinated aromatic polymer resins, (modified) acrylic resins, epoxy resins, silsesquioxane ultraviolet-curable resins, maleimide resins, alicyclic epoxy thermosetting resins, polyether ether ketone resins, polyarylate resins, allyl ester curable resins, acrylic ultraviolet-curable resins, vinyl ultraviolet-curable resins, and resins containing silica as a main component formed by the sol-gel method. Among these, it is preferable to use a cyclic polyolefin resin, an aromatic polyether resin, a fluorene polycarbonate-based resin, a fluorene polyester-based resin, a polycarbonate-based resin, or a polyarylate-based resin because an optical filter having excellent balance of transparency (optical properties), heat resistance, and reflow resistance can be obtained, and further, from the viewpoint of the refractive index of the resin, a cyclic polyolefin resin is particularly preferable. The transparent resin may be used alone, or two or more types may be used in combination.

≪Fantasy Polyolefin Resin≫

As the cyclic polyolefin resin, a resin obtained from at least one monomer selected from the group consisting of a monomer represented by the following formula (X ₀ ) and a monomer represented by the following formula (Y ₀ ), and a resin obtained by adding hydrogen to the resin are preferable.

In the formula (X ₀ ), R ^x1 to R ^x4 each independently represent an atom or group selected from the following (i') to (ix'), and k ^x , m ^{x ,} and p ^x each independently represent an integer from 0 to 4.

(i') hydrogen atom

(ii') halogen atom

(iii') Trialkylsilyl group

(iv') a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms having a linking group containing an oxygen atom, a sulfur atom, a nitrogen atom or a silicon atom;

(v') a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms;

(vi') Polarity (except (ii') and (iv'))

(vii') an alkylidene group formed by combining R ^x1 and R ^x2 or R ^x3 and R ^x4 (provided that R ^x1 to R ^x4 not involved in the combination each independently represent an atom or group selected from (i') to (vi') above).

(viii') a monocyclic or polycyclic hydrocarbon ring or heterocycle formed by combining R ^x1 and R ^x2 or R ^x3 and R ^x4 (provided that R ^x1 to R ^x4 not involved in the above combination each independently represent an atom or group selected from (i') to (vi') above);

(ix') A monocyclic hydrocarbon ring or heterocycle formed by combining R ^x2 and R ^x3 (provided that R ^x1 and R ^x4 , which are not involved in the combination, each independently represent an atom or group selected from (i') to (vi') above).

In formula (Y ₀ ), R ^y1 and R ^y2 each independently represent an atom or group selected from (i') to (vi') above, or a monocyclic or polycyclic alicyclic hydrocarbon, aromatic hydrocarbon or heterocycle formed by combining R ^y1 and R ^y2 , and k ^y and p ^y each independently represent an integer from 0 to 4.

≪Aromatic polyether resin≫

It is preferable that the aromatic polyether resin have at least one structural unit selected from the group consisting of a structural unit represented by the following formula (1) and a structural unit represented by the following formula (2).

In formula (1), R ¹ to R ⁴ each independently represent a monovalent organic group having 1 to 12 carbon atoms, and a to d each independently represent an integer from 0 to 4.

In formula (2), R ¹ to R ⁴ and a to d each independently have the same meaning as R ¹ to R ⁴ and a to d in formula (1), Y represents a single bond, -SO ₂ - or -CO-, R ⁷ and R ⁸ each independently represent a halogen atom, a monovalent organic group having 1 to 12 carbon atoms, or a nitro group, g and h each independently represent an integer of 0 to 4, and m represents 0 or 1. However, when m is 0, R ⁷ is not a cyano group.

In addition, it is preferable that the above-mentioned aromatic polyether resin additionally has at least one structural unit selected from the group consisting of a structural unit represented by the following formula (3) and a structural unit represented by the following formula (4).

In formula (3), R ⁵ and R ⁶ each independently represent a monovalent organic group having 1 to 12 carbon atoms, Z represents a single bond, -O-, -S-, -SO ₂ -, -CO-, -CONH-, -COO-, or a divalent organic group having 1 to 12 carbon atoms, e and f each independently represent an integer of 0 to 4, and n represents 0 or 1.

In formula (4), R ⁷ , R ⁸ , Y, m, g and h each independently have the same meaning as R ⁷ , R ⁸ , Y, m, g and h in formula (2), and R ⁵ , R ⁶ , Z, n, e and f each independently have the same meaning as R ⁵ , R ⁶ , Z, n, e and f in formula (3).

≪Polyimide resin≫

There are no particular restrictions on the polyimide resin, and any polymer compound containing an imide bond in the repeating unit may be used. For example, the polyimide resin can be synthesized by a method described in Japanese Patent Application Laid-Open No. 2006-199945 or Japanese Patent Application Laid-Open No. 2008-163107.

≪Fluorene polycarbonate resin≫

The fluorene polycarbonate resin is not particularly limited, and any polycarbonate resin containing a fluorene moiety may be used. For example, the resin can be synthesized by a method described in Japanese Patent Application Laid-Open No. 2008-163194.

≪Fluorene polyester resin≫

There is no particular limitation on the fluorene polyester resin, and any polyester resin containing a fluorene moiety may be used. For example, the resin may be synthesized by a method described in Japanese Patent Application Laid-Open No. 2010-285505 or Japanese Patent Application Laid-Open No. 2011-197450.

≪Fluorinated aromatic polymer resin≫

The fluorinated aromatic polymer resin is not particularly limited, but is preferably a polymer containing a repeating unit including an aromatic ring having at least one fluorine atom and at least one bond selected from the group consisting of an ether bond, a ketone bond, a sulfone bond, an amide bond, an imide bond, and an ester bond, and can be synthesized by, for example, a method described in Japanese Patent Application Laid-Open No. 2008-181121.

≪Acrylic UV-curable resin≫

Examples of the acrylic UV-curable resin include, but are not particularly limited to, those synthesized from a resin composition containing a compound having one or more acrylic groups or methacrylic groups in the molecule and a compound that is decomposed by ultraviolet rays to generate active radicals. The acrylic UV-curable resin can be particularly suitably used as the curable resin when a substrate is used in which a transparent resin layer containing the compound (A) and a curable resin is laminated on a glass support or a base resin support, or in which a resin layer such as an overcoat layer containing a curable resin or the like is laminated on a transparent resin substrate containing the compound (A).

≪Epoxy Resin≫

There are no particular limitations on the epoxy resin, but it can be broadly classified into ultraviolet-curable and thermosetting types. As the ultraviolet-curable epoxy resin, for example, one synthesized from a composition containing a compound having one or more epoxy groups in the molecule and a compound that generates an acid by ultraviolet rays (hereinafter also referred to as a "photoacid generator") can be exemplified, and as the thermosetting epoxy resin, for example, one synthesized from a composition containing a compound having one or more epoxy groups in the molecule and an acid anhydride can be exemplified. The epoxy ultraviolet-curable resin can be particularly suitably used as the curable resin when a substrate is used in which a transparent resin layer containing the compound (A) is laminated on a glass support or a base resin support, or in which a resin layer such as an overcoat layer containing a curable resin or the like is laminated on a transparent resin substrate containing the compound (A).

≪Resin with silica as the main component formed by the sol-gel method≫

As a resin containing silica as a main component obtained by the sol-gel method, a compound obtained by a sol-gel reaction through hydrolysis of one or more silanes selected from the following groups: tetraalkoxysilanes such as tetramethoxysilane, tetraethoxysilane, dimethoxydiethoxysilane, and methoxytriethoxysilane; phenylalkoxysilanes such as phenyltrimethoxysilane, phenyltriethoxysilane, diphenyldimethoxysilane, and diphenyldiethoxysilane; and the like.

≪Commercial Product≫

Examples of commercially available transparent resins include the following commercially available products. Examples of commercially available cyclic polyolefin resins include Aton manufactured by JSR Corporation, ZEONOA manufactured by Nippon Zeon Co., Ltd., APEL manufactured by Mitsui Kagaku Corporation, and TOPAS manufactured by Polyplastics Co., Ltd. Examples of commercially available polyethersulfone resins include Sumika Excel PES manufactured by Sumitomo Chemical Co., Ltd. Examples of commercially available polyimide resins include Neopulim L manufactured by Mitsubishi Gas Chemical Co., Ltd. Examples of commercially available polycarbonate resins include Pureace manufactured by Teijin Corporation. Examples of commercially available fluorene polycarbonate resins include UPI Zeta EP-5000 manufactured by Mitsubishi Gas Chemical Co., Ltd. Examples of commercial products of fluorene polyester resins include OKP4HT manufactured by Osaka Gas Chemical Co., Ltd. Examples of commercial products of acrylic resins include Acriviewer manufactured by Nippon Shokubai Co., Ltd. Examples of commercial products of silsesquioxane UV-curable resins include Silplus manufactured by Nippon Steel Chemical Co., Ltd.

<Other pigments (X)>

The above description may additionally contain other pigments (X) that do not correspond to the above compound (A).

As the other pigment (X), there is no particular limitation as long as it is a pigment having a maximum absorption wavelength in a range of less than 650 nm or more than 800 nm and less than or equal to 1,250 nm, and examples thereof include at least one compound selected from the group consisting of squarylium compounds, phthalocyanine compounds, cyanine compounds, naphthalocyanine compounds, croconium compounds, octapyrine compounds, dimonium compounds, pyrrolopyrrole compounds, boron dipyrromethene (BODIPY) compounds, perylene compounds, and metal dithiolate compounds. By using such a pigment, absorption characteristics in a wide near-infrared wavelength range and excellent visible light transmittance can be achieved.

The maximum absorption wavelength of the other pigment (X) is preferably 805 nm or more and 1200 nm or less, more preferably 810 nm or more and 1150 nm or less, even more preferably 815 nm or more and 1100 nm or less, and particularly preferably 820 nm or more and 1050 nm or less. When the maximum absorption wavelength of the other pigment (X) is in this range, unnecessary near-infrared rays can be efficiently cut, and the dependence of the incident angle of incident light can be reduced.

The content of the other pigment (X) is, when using a substrate including, for example, a transparent resin substrate containing the other pigment (X) as the substrate, preferably 0.005 to 1.0 parts by mass, more preferably 0.01 to 0.9 parts by mass, and particularly preferably 0.02 to 0.8 parts by mass, relative to 100 parts by mass of the transparent resin. When using a substrate in which a transparent resin layer such as an overcoat layer containing a curable resin containing the other pigment (X) is laminated on a support such as a glass support or a base resin support as the substrate, or a resin layer such as an overcoat layer containing a curable resin containing the other pigment (X) is laminated on a transparent resin substrate containing the compound (A), the content is preferably 0.05 to 4.0 parts by mass, more preferably 0.1 to 3.0 parts by mass, and particularly preferably 0.2 to 2.0 parts by mass, relative to 100 parts by mass of the resin forming the transparent resin layer containing the other pigment (X).

<Other ingredients>

The above description may additionally contain other components such as antioxidants, near-ultraviolet absorbers, and fluorescent quenchers, as long as the effects of the present invention are not impaired. These other components may be used alone, or two or more may be used in combination.

Examples of the above near-ultraviolet absorbers include azomethine compounds, indole compounds, benzotriazole compounds, triazine compounds, and cyanoacrylate compounds.

Examples of the antioxidants include 2,6-di-t-butyl-4-methylphenol, 2,2'-dioxy-3,3'-di-t-butyl-5,5'-dimethyldiphenylmethane, tetrakis[methylene-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate]methane, and tris(2,4-di-t-butylphenyl)phosphite.

In addition, these other components may be mixed with resins, etc. when manufacturing the substrate, or may be added when synthesizing the resin. In addition, the amount to be added is appropriately selected depending on the desired properties, but is usually 0.01 to 5.0 parts by mass, and preferably 0.05 to 2.0 parts by mass, per 100 parts by mass of the resin.

<Method of manufacturing the article>

When the above-mentioned substrate is a substrate including a transparent resin substrate containing a compound (A), the transparent resin substrate can be formed by, for example, melt molding or cast molding, and further, if necessary, by coating a coating agent such as an antireflection agent, a hard coating agent, and/or an antistatic agent after molding, a substrate having an overcoat layer laminated thereon can be manufactured.

When the above-mentioned substrate is a substrate in which a transparent resin layer, such as an overcoat layer, including a curable resin, etc., containing compound (A) is laminated on a support such as a glass support or a base resin support, or on a transparent resin substrate that does not contain compound (A), for example, by melt molding or cast molding a resin solution containing compound (A) onto the support or the transparent resin substrate, preferably by spin coating, slit coating, inkjet, or the like, and then drying and removing the solvent, and if necessary, additionally performing light irradiation or heating, a substrate in which a transparent resin layer containing compound (A) is formed on the support or the transparent resin substrate can be manufactured.

≪Melting Molding≫

Specific examples of the above melt molding include a method of melt molding pellets obtained by melt mixing a resin, a compound (A), and other components as needed; a method of melt molding a resin composition containing a resin, a compound (A), and other components as needed; or a method of melt molding pellets obtained by removing a solvent from a resin composition containing a compound (A), a resin, a solvent, and other components as needed. Examples of the melt molding method include injection molding, melt extrusion molding, and blow molding.

≪Cast Molding≫

As the above casting molding, the method may be produced by casting a resin composition containing a compound (A), a resin, a solvent, and other components as needed, onto a suitable support, and removing the solvent; or a method of casting a curable composition containing a compound (A), a photocurable resin and/or a thermocurable resin, and other components as needed, onto a suitable support, removing the solvent, and then curing by an appropriate method such as ultraviolet irradiation or heating.

If the above-mentioned substrate is a substrate including a transparent resin substrate containing compound (A), the substrate can be obtained by peeling off the coating film from the support after cast molding, and further, if the substrate is a substrate in which a transparent resin layer, such as an overcoat layer including a curable resin containing compound (A), is laminated on a support such as a glass support or a base resin support or on a transparent resin substrate not containing compound (A), the substrate can be obtained by not peeling off the coating film after cast molding.

Examples of the support include a near-infrared absorbing glass plate (for example, a phosphate glass plate containing a copper component, such as “BS-11” manufactured by Matsunami Glass Kogyo Co., Ltd. or “NF-50T” manufactured by AGC Techno Glass Co., Ltd.), a transparent glass plate (for example, an alkali-free glass plate, such as “OA-10G” manufactured by Nippon Denki Glass Co., Ltd. or “AN100” manufactured by Asahi Glass Co., Ltd.), a steel belt, a steel drum, and a support made of a transparent resin (for example, a polyester film or a cyclic olefin resin film).

In addition, a transparent resin layer can be formed on an optical component such as a glass plate, quartz or transparent plastic by a method such as coating the resin composition and drying the solvent, or by a method such as coating the curable composition and curing and drying it.

The amount of residual solvent in the transparent resin layer (transparent resin substrate) obtained by the above method should be as small as possible. Specifically, the amount of residual solvent is preferably 3 parts by mass or less, more preferably 1 part by mass or less, and even more preferably 0.5 parts by mass or less, based on 100 parts by mass of the weight of the transparent resin layer (transparent resin substrate). When the amount of residual solvent is within the above range, a transparent resin layer (transparent resin substrate) that is unlikely to be deformed or have its characteristics changed and can easily exhibit a desired function is obtained.

[Genetic multilayer film]

It is preferable that the optical filter of the present invention does not have a dielectric multilayer film, but may have a dielectric multilayer film on at least one side of the substrate as long as the effect of the present invention is not impaired. The dielectric multilayer film in the present invention is a film having an antireflection effect in the visible light range.

The above dielectric multilayer film preferably has antireflection properties over the entire range of wavelengths from 400 to 610 nm, more preferably from 410 to 600 nm, and even more preferably from 420 to 590 nm.

Examples include a form having a dielectric multilayer film on both sides of the substrate, and a form having a dielectric multilayer film on both sides of the substrate, which has an antireflection characteristic mainly in the vicinity of a wavelength of 400 to 610 nm when measured from the vertical direction of the optical filter.

The thickness of the dielectric multilayer film having an antireflection effect in the above-mentioned visible light range is not particularly limited as long as it does not impair the effect of the present invention, but is preferably 0.01 to 1.0 µm, more preferably 0.05 to 0.5 µm. By setting the thickness within the above-mentioned range, an optical filter with little warping or deformation can be obtained.

As a dielectric multilayer film, there can be mentioned one in which high refractive index material layers and low refractive index material layers are alternately laminated. As a material constituting the high refractive index material layer, a material having a refractive index of 1.7 or higher can be used, and a material having a refractive index of 1.7 to 2.5 is usually selected. Examples of such materials include those containing titanium oxide, zirconium oxide, tantalum pentoxide, niobium pentoxide, lanthanum oxide, yttrium oxide, zinc oxide, zinc sulfide, or indium oxide as a main component, and containing a small amount of tin oxide and/or cerium oxide (for example, 0 to 10 parts by mass with respect to 100 parts by mass of the main component).

As a material constituting the low refractive index material layer, a material having a refractive index of 1.6 or less can be used, and a material having a refractive index of 1.2 to 1.6 is usually selected. Examples of such materials include silica, alumina, lanthanum fluoride, magnesium fluoride, and sodium aluminum hexafluoride.

There is no particular limitation on the method for laminating the high refractive index material layer and the low refractive index material layer, as long as a dielectric multilayer film is formed by laminating these material layers. For example, a dielectric multilayer film in which high refractive index material layers and low refractive index material layers are alternately laminated can be formed directly on a substrate by a CVD method, a sputtering method, a vacuum deposition method, an ion-assisted deposition method, or an ion plating method.

The thickness of each layer of the high refractive index material layer and the low refractive index material layer is preferably 0.1λ to 0.5λ, where λ (nm) is the near-infrared wavelength to be blocked. The value of λ (nm) is, for example, 700 to 1400 nm, preferably 750 to 1300 nm. When the thickness is in this range, the optical film thickness calculated by the product of the refractive index (n) and the film thickness (d) (n × d) as λ/4 and the thickness of each layer of the high refractive index material layer and the low refractive index material layer become almost the same value, so that there is a tendency for the blocking/transmission of a specific wavelength to be easily controlled from the relationship between the optical characteristics of reflection and refraction.

The total number of layers of high refractive index material layers and low refractive index material layers in the dielectric multilayer film is preferably 1 to 20 layers for the entire optical filter, and more preferably 2 to 12 layers. By setting the number of layers within the above range, an optical filter with less warping or deformation can be obtained.

In the present invention, by appropriately selecting the material types constituting the high refractive index material layer and the low refractive index material layer, the thickness of each layer of the high refractive index material layer and the low refractive index material layer, the order of lamination, and the number of laminations in accordance with the absorption characteristics of the compound (A) or other pigment (X), not only is sufficient transmittance secured in the visible light range, but also sufficient light cut characteristics are provided in the near-infrared wavelength range, and further, reflectance can be reduced when near-infrared light is incident from an oblique direction.

Here, in order to optimize the above conditions, for example, optical thin film design software (e.g., Essential Macleod, Thin Film Center) can be used to set parameters so as to achieve both an anti-reflection effect in the visible light range and a light-cutting effect in the near-infrared range. In the case of the software, for example, when designing the first optical layer, a parameter setting method may be exemplified, such as setting the target transmittance for a wavelength of 400 to 700 nm to 100% and the target tolerance value to 1, and then setting the target transmittance for a wavelength of 705 to 950 nm to 0% and the target tolerance value to 0.5. These parameters can also be used to further finely divide the wavelength range according to various characteristics of the substrate (i) and change the target tolerance value.

[Other functional barriers]

The optical filter of the present invention may, within a range that does not impair the effects of the present invention, appropriately provide a functional film, such as an antireflection film, a hard coating film, or an antistatic film, on at least one side of the substrate, between the substrate and the dielectric multilayer film, the side of the substrate opposite to the side on which the dielectric multilayer film is provided, or the side of the dielectric multilayer film opposite to the side on which the substrate is provided, for the purposes of improving the surface hardness of the substrate or the dielectric multilayer film, improving chemical resistance, preventing static electricity, and removing scratches.

The optical filter of the present invention may include one layer including the functional film, or may include two or more layers. When the optical filter of the present invention includes two or more layers including the functional film, it may include two or more layers of the same layer, or it may include two or more layers of different layers.

The method for laminating the functional film is not particularly limited, but may include a method of melt molding or cast molding, similar to the above, by applying a coating agent, such as an antireflection agent, a hard coating agent, and/or an antistatic agent, to the substrate or dielectric multilayer film.

In addition, the curable composition including the coating agent, etc. can also be manufactured by applying it onto a substrate or a dielectric multilayer film using a bar coater, etc., and then curing it by ultraviolet irradiation, etc.

As the coating agent, examples thereof include ultraviolet (UV)/electron beam (EB) curable resins and thermosetting resins, and specifically, examples thereof include vinyl compounds, urethane-based, urethane acrylate-based, acrylate-based, epoxy-based, and epoxy acrylate-based resins. As the curable composition containing these coating agents, examples thereof include vinyl-based, urethane-based, urethane acrylate-based, acrylate-based, epoxy-based, and epoxy acrylate-based curable compositions.

In addition, the curable composition may contain a polymerization initiator. As the polymerization initiator, a known photopolymerization initiator or thermal polymerization initiator may be used, and a photopolymerization initiator and a thermal polymerization initiator may be used in combination. The polymerization initiator may be used alone or in combination of two or more types.

The mixing ratio of the polymerization initiator in the above-mentioned curable composition is preferably 0.1 to 10 parts by mass, more preferably 0.5 to 10 parts by mass, and even more preferably 1 to 5 parts by mass, based on 100 parts by mass of the total amount of the curable composition. When the mixing ratio of the polymerization initiator is within the above range, the curing characteristics and handleability of the curable composition are excellent, and a functional film such as an antireflection film, a hard coating film, or an antistatic film having a desired hardness can be obtained.

In addition, an organic solvent may be added as a solvent to the above-mentioned curable composition, and a known organic solvent can be used as the organic solvent. Specific examples of the organic solvent include alcohols such as methanol, ethanol, isopropanol, butanol, and octanol; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; esters such as ethyl acetate, butyl acetate, ethyl lactate, γ-butyrolactone, propylene glycol monomethyl ether acetate, and propylene glycol monoethyl ether acetate; ethers such as ethylene glycol monomethyl ether and diethylene glycol monobutyl ether; aromatic hydrocarbons such as benzene, toluene, and xylene; and amides such as dimethylformamide, dimethylacetamide, and N-methylpyrrolidone. One type of the solvent may be used alone, or two or more types may be used in combination.

The thickness of the above functional film is preferably 0.1 to 20 μm, more preferably 0.5 to 10 μm, and particularly preferably 0.7 to 5 μm.

In addition, in order to increase the adhesion between the substrate and the functional film and/or the dielectric multilayer film, or the adhesion between the functional film and the dielectric multilayer film, surface treatment such as corona treatment or plasma treatment may be performed on the surface of the substrate, the functional film, or the dielectric multilayer film.

[Uses of optical filters]

The optical filter of the present invention has a wide viewing angle, excellent near-infrared cutting ability, etc. Therefore, it is useful for correcting the sensitivity of a solid-state imaging element such as a CCD or CMOS image sensor of a camera module. In particular, it is useful for a digital still camera, a camera for a smartphone, a camera for a mobile phone, a digital video camera, a camera for a wearable device, a PC camera, a surveillance camera, a camera for an automobile, a television, a car navigation system, a portable information terminal, a video game console, a portable game console, a fingerprint authentication system, a digital music player, etc. In addition, it is also useful as a heat-cutting filter mounted on a glass panel of an automobile, a building, etc.

Here, the solid-state imaging device refers to an image sensor having a solid-state imaging element such as a CCD or CMOS image sensor, and can be specifically used for purposes such as a digital still camera, a camera for a smartphone, a camera for a mobile phone, a camera for a wearable device, a digital video camera, etc. For example, the camera module of the present invention has the optical filter of the present invention. Here, the camera module refers to a device having an image sensor, a focus adjustment mechanism, or a phase detection mechanism, a distance measuring mechanism, etc., and outputting an image or distance information as an electric signal.

It is particularly preferable that the above camera module has a cover member that protects the internal mechanism from the outside, and that the cover member has a near-infrared reflection function. The near-infrared wavelength band in which the cover member has a reflection function with respect to light incident from a vertical direction of the cover member is preferably 900 to 1100 nm, more preferably 850 to 1150 nm, and particularly preferably 800 to 1200 nm. The means for imparting the near-infrared reflection function to the cover member is not particularly limited, but a method in which a dielectric multilayer film in which a high-refractive-index material and a low-refractive-index material are alternately laminated is formed on the cover member by a CVT method, a sputtering method, a vacuum deposition method, an ion-assisted deposition method, or the like is preferable.

When the camera module has the above configuration, since the light enters the camera module with a portion of the near-infrared ray cut by the cover member, unnecessary near-infrared reflection between lenses, between the lens and the optical filter, and between the optical filter and the solid-state imaging element can be reduced, and there is a tendency for noise or ghosting in the camera image to be reduced, which is preferable. In addition, since the camera module of the present invention comprises an optical filter that efficiently cuts near-infrared ray having a wavelength of 700 to 780 nm by absorption by the compound (A), high image quality that is difficult to achieve with a conventional camera module can be achieved.

In addition, the electronic device of the present invention has the camera module of the present invention. The electronic device is not particularly limited, but examples thereof include a smartphone, a mobile phone, a PC, etc. for the above-described purposes.

Example

Hereinafter, the present invention will be described more specifically based on examples, but the present invention is not limited to these examples at all. In addition, "part" means "mass part" unless specifically stated otherwise. In addition, the measurement method of each property value and the evaluation method of the property are as follows.

<Molecular weight>

The molecular weight of the resin was measured by the following method (a) or (b), taking into account the solubility of each resin in a solvent, etc.

(a) The mass average molecular weight (Mw) and number average molecular weight (Mn) converted to standard polystyrene were measured using a gel permeation chromatography (GPC) apparatus (150C type, column: H type column manufactured by Tosoh Corporation, developing solvent: o-dichlorobenzene) manufactured by WATERS.

(b) The mass average molecular weight (Mw) and number average molecular weight (Mn) converted to standard polystyrene were measured using a GPC apparatus (HLC-8220 type, column: TSKgelα-M, developing solvent: THF).

In addition, for the resin synthesized in the resin synthesis example 3 described below, the logarithmic viscosity was measured by the following method (c) instead of the molecular weight measured by the above method.

(c) A portion of the polyimide resin solution was poured into anhydrous methanol to precipitate the polyimide resin, which was then filtered to separate it from the unreacted monomer. 0.1 g of the polyimide obtained by vacuum drying at 80°C for 12 hours was dissolved in 20 mL of N-methyl-2-pyrrolidone, and the logarithmic viscosity (μ) at 30°C was determined by the following equation using a Cannon-Fenske viscometer.

μ={ln(t _s /t ₀ )}/C

t ₀ : solvent flow time

t _s : Flow time of dilute polymer solution

C: 0.5g/dL

<Glass transition temperature (Tg)>

Measurements were made using a differential scanning calorimeter (DSC6200) manufactured by SIII Nanotechnologies, Inc., at a heating rate of 20°C per minute under a nitrogen flow.

<Spectral transmittance>

The transmittance at each wavelength of the substrate and optical filters was measured using a spectrophotometer (U-4100) manufactured by Hitachi High-Technologies, Inc.

Here, in the case of the transmittance measured from the vertical direction of the optical filter, light (1) transmitted vertically to the optical filter (2) as in (A) of Fig. 1 was measured with a spectrophotometer (3), and in the case of the transmittance measured from an angle of 30 degrees to the vertical direction of the optical filter, light (1') transmitted at an angle of 30 degrees to the vertical direction of the optical filter (2) as in (B) of Fig. 1 was measured with a spectrophotometer (3), and in the case of the transmittance measured from an angle of 60 degrees to the vertical direction of the optical filter, light (1'') transmitted at an angle of 60 degrees to the vertical direction of the optical filter (2) as in (C) of Fig. 1 was measured with a spectrophotometer (3).

<Evaluation of color shading of camera images>

The color shading evaluation when the optical filter was built into the camera module was performed by the following method. A camera module as shown in Fig. 2 was manufactured by the same method as in Japanese Patent Application Laid-Open No. 2016-110067, and the obtained camera module was used to photograph a white plate sized 300 mm × 400 mm under a D65 light source (standard light source device "Macbeth Judge II" manufactured by X-Rite), and the difference in color tone between the center and edges of the white plate in the camera image was evaluated according to the following criteria.

The acceptable level was determined as A because there was no problem at all; the acceptable level was determined as B because there was a slight difference in color tone but there was no practical problem as a high-definition camera module; the acceptable level was determined as C because there was a difference in color tone and it was unacceptable for use as a high-definition camera module; and the acceptable level was determined as D because there was a clear difference in color tone and it was unacceptable even for use as a general camera module.

In addition, as shown in Fig. 3, when taking pictures, the positional relationship between the white plate (112) and the camera module was adjusted so that the white plate (112) occupies 90% or more of the area of the camera image (111). In addition, as the cover member (210) in Fig. 2, a cover member having a film configuration shown in Table 9 below was used, and as the optical filter (240), the optical filter manufactured in the following examples and comparative examples was used.

[Table 9]

<Ghost Evaluation of Camera Images>

Ghost evaluation when an optical filter was built into a camera module was performed using the following method. A camera module was manufactured using the same method as for the color shading evaluation of a camera image, and the manufactured camera module was used to take pictures in a dark room under a halogen lamp light source ("Luminace LA-150TX" manufactured by Hayashi Tokei High School), and the ghost occurrence status around the light source in the camera image was evaluated using the following criteria.

The acceptable level was given as A because there were no problems at all; the acceptable level was given as B because slight ghosting was confirmed but there were no practical problems as a high-definition camera module; the acceptable level was given as C because ghosting occurred and was unacceptable for use as a high-definition camera module; and the acceptable level was given as D because the degree of ghosting was so severe that it was unacceptable even for use as a general camera module.

Additionally, as shown in Fig. 4, when taking pictures, the light source (122) was adjusted to be at the upper right part of the camera image (121).

[Synthetic example]

The compound (A) and near-infrared absorbing dye (X) used in the examples below were synthesized by generally known methods. As general synthetic methods, for example, methods described in Japanese Patent Application Laid-Open No. S60-228448, Japanese Patent Application Laid-Open No. H1-146846, Japanese Patent Application Laid-Open No. H1-228960, Japanese Patent No. 4081149, Japanese Patent Application Laid-Open No. S63-124054, “Phthalocyanine -Chemistry and Function-” (IPC, 1997), Japanese Patent Application Laid-Open No. 2007-169315, Japanese Patent Application Laid-Open No. 2009-108267, Japanese Patent Application Laid-Open No. 2010-241873, etc. can be cited.

<Resin synthesis example 1>

100 parts of 8-methyl-8- ^{methoxycarbonyltetracyclo} [ ^{4.4.0.12,5.17,10} ]dodeca-3-ene (hereinafter referred to as "DNM") represented by the following formula (a), 18 parts of 1-hexene (molecular weight regulator), and 300 parts of toluene (solvent for ring-opening polymerization reaction) were placed in a nitrogen-purged reaction vessel, and the solution was heated to 80°C. Next, 0.2 part of a toluene solution (0.6 mol/L) of triethylaluminum as a polymerization catalyst and 0.9 part of a toluene solution (concentration: 0.025 mol/L) of methanol-modified tungsten hexachloride were added to the solution in the reaction vessel, and the solution was stirred and heated at 80°C for 3 hours to cause a ring-opening polymerization reaction, thereby obtaining a ring-opening polymer solution. The polymerization conversion rate in this polymerization reaction was 97%.

1,000 parts of the ring-opening polymer solution thus obtained were placed into an autoclave, 0.12 parts of RuHCl(CO)[P(C ₆ H ₅ ) ₃ ] ₃ were added to the ring-opening polymer solution, and the mixture was heated and stirred for 3 hours under the conditions of a hydrogen gas pressure of 100 kg/cm ² and a reaction temperature of 165°C to perform a hydrogenation reaction. After the obtained reaction solution (hydrogenated polymer solution) was cooled, the hydrogen gas was released. This reaction solution was injected into a large amount of methanol, the coagulated product was separated and recovered, and this was dried to obtain a hydrogenated polymer (hereinafter also referred to as “resin A”). The obtained resin A had a number average molecular weight (Mn) of 32,000, a mass average molecular weight (Mw) of 137,000, a glass transition temperature (Tg) of 165°C, and a refractive index (n20d) of 1.51.

<Suji Synthesis Example 2>

In a 3 L four-necked flask were added 35.12 g (0.253 mol) of 2,6-difluorobenzonitrile, 87.60 g (0.250 mol) of 9,9-bis(4-hydroxyphenyl)fluorene, 41.46 g (0.300 mol) of potassium carbonate, 443 g of N,N-dimethylacetamide (hereinafter referred to as “DMAc”), and 111 g of toluene. Subsequently, a thermometer, a stirrer, a three-way stopcock equipped with a nitrogen introduction tube, a Dean-Stark tube, and a condenser were installed in the four-necked flask. Then, after the inside of the flask was replaced with nitrogen, the obtained solution was reacted at 140°C for 3 hours, and the produced water was periodically removed from the Dean-Stark tube. When the production of water was no longer confirmed, the temperature was gradually raised to 160°C, and the reaction was carried out at that temperature for 6 hours. After cooling to room temperature (25°C), the generated salt was removed with a filter paper, the filtrate was reprecipitated in methanol, and the filtrate (residue) was isolated by filtration. The obtained filtrate was vacuum-dried overnight at 60°C to obtain a white powder (hereinafter also referred to as “resin B”) (yield: 95%). The obtained resin B had a number average molecular weight (Mn) of 75,000, a mass average molecular weight (Mw) of 188,000, a glass transition temperature (Tg) of 285°C, and a refractive index (n20d) of 1.66.

<Resin Synthesis Example 3>

In a 500 mL five-necked flask equipped with a thermometer, a stirrer, a nitrogen inlet tube, a dropping funnel with a side tube, a Dean-Stark tube and a condenser, under a nitrogen flow, 27.66 g (0.08 mol) of 1,4-bis(4-amino-α,α-dimethylbenzyl)benzene and 7.38 g (0.02 mol) of 4,4'-bis(4-aminophenoxy)biphenyl were added, and 68.65 g of γ-butyrolactone and 17.16 g of N,N-dimethylacetamide were dissolved. The obtained solution was cooled to 5°C using an ice water bath, and while maintaining it at the same temperature, 22.62 g (0.1 mol) of 1,2,4,5-cyclohexanetetracarboxylic dianhydride and 0.50 g (0.005 mol) of triethylamine as an imidization catalyst were added in batches. After the addition was completed, the temperature was raised to 180°C, and the mixture was refluxed for 6 hours while occasionally distilling off the effluent. After the reaction was completed, the mixture was cooled in the air until the internal temperature reached 100°C, 143.6 g of N,N-dimethylacetamide was added to dilute, and the mixture was cooled while stirring to obtain 264.16 g of a polyimide resin solution having a solid concentration of 20 mass%. A portion of this polyimide resin solution was poured into 1 L of methanol to precipitate the polyimide. The filtered-out polyimide was washed with methanol, and then dried in a vacuum dryer at 100°C for 24 hours to obtain a white powder (hereinafter also referred to as “resin C”). As a result of measuring the IR spectrum of the obtained resin C, absorptions at 1704 cm ^-1 and 1770 cm ^-1 characteristic of the imide group were observed. Resin C had a glass transition temperature (Tg) of 310°C, a refractive index (n20d) of 1.68, and a logarithmic viscosity of 0.87.

[Example 1]

In a container, 100 parts of the resin A obtained in Resin Synthesis Example 1, 0.05 part of a compound (A-a-1) represented by the following formula (A-a-1) (maximum absorption wavelength in dichloromethane: 712 nm), 0.12 part of a compound (A-b-1) represented by the following formula (A-b-1) (maximum absorption wavelength in dichloromethane: 738 nm), and 0.05 part of a compound (A-c-1) represented by the following formula (A-c-1) (maximum absorption wavelength in dichloromethane: 776 nm) as compound (A-c) and methylene chloride were added to prepare a solution having a resin concentration of 20 mass%. The obtained solution was cast on a smooth glass plate, dried at 20°C for 8 hours, and then peeled from the glass plate. The peeled film was further dried at 100°C under reduced pressure for 8 hours to obtain a substrate including a transparent resin substrate having a thickness of 0.1 mm, a length of 60 mm, and a width of 60 mm. The spectral transmittance of an optical filter including this substrate was measured to evaluate the optical properties. In addition, a camera module was manufactured using the obtained optical filter, and color shading and ghosting of the camera image were evaluated. The results are shown in Fig. 5 and Table 15.

[Example 2]

In Example 1, 0.03 part of a compound (A-a-2) (maximum absorption wavelength 686 nm in dichloromethane) represented by the following formula (A-a-2) was used as compound (A-a), compound (A-b) was not used, and 0.04 part of a compound (A-c-1) and 0.06 part of a compound (A-c-2) represented by the following formula (A-c-2) (maximum absorption wavelength 760 nm in dichloromethane) were used as compound (A-c), respectively, a transparent resin substrate was obtained under the same procedures and conditions as in Example 1.

On one side of the obtained transparent resin substrate, a resin composition (1) having the following composition was applied with a bar coater, and heated in an oven at 70° C. for 2 minutes to volatilize and remove the solvent. At this time, the application conditions of the bar coater were adjusted so that the thickness after drying became 2 μm. Next, exposure (exposure amount: 500 mJ/cm ² , 200 mW) was performed using a conveyor-type exposure machine to harden the resin composition (1), thereby forming a resin layer on the transparent resin substrate. Similarly, a resin layer containing the resin composition (1) was formed on the other side of the transparent resin substrate, thereby obtaining a substrate having resin layers on both sides of the transparent resin substrate. The spectral transmittance of an optical filter containing this substrate was measured to evaluate the optical characteristics. In addition, a camera module was manufactured using the obtained optical filter, and color shading and ghosting of a camera image were evaluated. The results are shown in Fig. 6 and Table 15.

Resin composition (1): 60 parts of tricyclodecane dimethanol diacrylate, 40 parts of dipentaerythritol hexaacrylate, 5 parts of 1-hydroxycyclohexyl phenyl ketone, methyl ethyl ketone (solvent, solid content concentration (TSC): 30 mass%)

[Example 3]

In Example 1, except that 0.04 part of compound (A-a-1) and 0.03 part of compound (A-a-2) were used as the compound (A-a), 0.10 part of compound (A-b-1) was used as the compound (A-b), and 0.04 part of compound (A-c-1) and 0.05 part of compound (A-c-2) were used as the compound (A-c), a substrate including a transparent resin substrate was obtained by the same procedures and conditions as in Example 1. The spectral transmittance of an optical filter including this substrate was measured to evaluate the optical properties. In addition, a camera module was manufactured using the obtained optical filter, and color shading and ghosting of a camera image were evaluated. The results are shown in Fig. 7 and Table 15.

[Example 4]

In Example 1, 0.04 part of compound (A-a-1) and 0.03 part of compound (A-a-2) were used as the compound (A-a), 0.01 part of compound (A-b-1) was used as the compound (A-b), 0.03 part of compound (A-c-1) and 0.04 part of compound (A-c-2) were used as the compound (A-c), and 0.04 part of a near-infrared absorbing dye (X) represented by the following formula (X-1) (maximum absorption wavelength in dichloromethane: 813 nm) was used as the other near-infrared absorbing dye (X), and a substrate including a transparent resin substrate including a compound (A) and a near-infrared absorbing dye (X) was obtained in the same manner as in Example 1. The spectral transmittance of an optical filter including this substrate was measured to evaluate the optical properties. In addition, a camera module was fabricated using the obtained optical filter, and color shading and ghosting of the camera image were evaluated. The results are shown in Fig. 8 and Table 15.

[Example 5]

A resin composition (2) having the following composition was applied by a spin coater onto a transparent glass substrate "OA-10G (150 μm thick)" (manufactured by Nippon Denki Glass Co., Ltd.) cut to a size of 60 mm in length and 60 mm in width, and the solvent was volatilized and removed by heating on a hot plate at 80° C. for 2 minutes. At this time, the application conditions of the spin coater were adjusted so that the thickness after drying became 2 μm. Next, exposure (exposure dose: 500 mJ/cm ² , 200 mW) was performed using a conveyor-type exposure device to harden the resin composition (2), thereby obtaining a substrate including a transparent glass substrate having a transparent resin layer including a compound (A). The spectral transmittance of an optical filter including this substrate was measured to evaluate the optical properties. In addition, a camera module was manufactured using the obtained optical filter, and color shading and ghosting of a camera image were evaluated. The results are shown in Fig. 9 and Table 15.

Resin composition (2): 20 parts of tricyclodecane dimethanol diacrylate, 80 parts of dipentaerythritol hexaacrylate, 4 parts of 1-hydroxycyclohexyl phenyl ketone, 3.00 parts of compound (A-a-1), 1.00 parts of compound (A-a-2), 7.00 parts of compound (A-b-1), 4.00 parts of compound (A-c-1), methyl ethyl ketone (solvent, TSC: 35%)

[Example 6]

In Example 1, except that 0.04 part of compound (A-a-1) and 0.03 part of compound (A-a-2) were used as the compound (A-a), 0.34 part of compound (A-b-1) was used as the compound (A-b), 0.04 part of compound (A-c-1) was used as the compound (A-c), and the thickness of the transparent resin substrate was set to 0.08 mm, a substrate including a transparent resin substrate was obtained by the same procedures and conditions as in Example 1. The spectral transmittance of an optical filter including this substrate was measured to evaluate the optical properties. In addition, a camera module was manufactured using the obtained optical filter, and color shading and ghosting of a camera image were evaluated. The results are shown in Fig. 10 and Table 15.

[Example 7]

In Example 1, except that 0.05 part of compound (A-a-1) was used as the compound (A-a), 0.85 part of compound (A-b-1) was used as the compound (A-b), 0.05 part of compound (A-c-1) was used as the compound (A-c), and the thickness of the transparent resin substrate was set to 0.04 mm, a substrate including a transparent resin substrate was obtained by the same procedures and conditions as in Example 1. The spectral transmittance of an optical filter including this substrate was measured to evaluate the optical properties. In addition, a camera module was manufactured using the obtained optical filter, and color shading and ghosting of a camera image were evaluated. The results are shown in Fig. 11 and Table 15.

[Example 8]

In a container, resin A obtained in Resin Synthesis Example 1 and methylene chloride were added to prepare a solution having a resin concentration of 20 mass%, and a resin support was produced in the same manner as in Example 1, except that the obtained solution was used.

On both sides of the obtained resin support, a resin layer containing a resin composition (3) having the following composition was formed in the same manner as in Example 2, and a substrate having a transparent resin layer containing a compound (A) and a near-infrared absorbing dye (X) on both sides of the resin support was obtained. The spectral transmittance of an optical filter containing this substrate was measured to evaluate the optical properties. In addition, a camera module was manufactured using the obtained optical filter, and color shading and ghosting of a camera image were evaluated. The results are shown in Fig. 12 and Table 15.

Resin composition (3): 100 parts of tricyclodecane dimethanol diacrylate, 4 parts of 1-hydroxycyclohexyl phenyl ketone, 0.50 parts of compound (A-a-1), 0.50 parts of compound (A-c-1), 2.50 parts of compound (A-c-2), 1.40 parts of near-infrared absorbing pigment (X-1), methyl ethyl ketone (solvent, TSC: 25%)

[Example 9]

A resin composition (4) having the following composition was applied by a spin coater onto a near-infrared absorbing glass substrate "BS-11 (thickness: 120 μm)" (manufactured by Matsunami Glass Kogyo Co., Ltd.) cut to a size of 60 mm in length and 60 mm in width, and the solvent was volatilized and removed by heating on a hot plate at 80° C. for 2 minutes. At this time, the application conditions of the spin coater were adjusted so that the thickness after drying became 2 μm. Next, exposure (exposure dose: 500 mJ/cm ² , 200 mW) was performed using a conveyor-type exposure device to harden the resin composition (4), thereby obtaining a substrate including a near-infrared absorbing glass substrate having a transparent resin layer including a compound (A). The spectral transmittance of an optical filter including this substrate was measured to evaluate the optical properties. In addition, a camera module was manufactured using the obtained optical filter, and color shading and ghosting of a camera image were evaluated. The results are shown in Fig. 13 and Table 15.

Resin composition (4): 20 parts of tricyclodecane dimethanol diacrylate, 80 parts of dipentaerythritol hexaacrylate, 4 parts of 1-hydroxycyclohexyl phenyl ketone, 1.00 part of compound (A-a-1), 1.00 part of compound (A-c-1), 5.00 parts of compound (A-c-2), methyl ethyl ketone (solvent, TSC: 35 mass%)

[Example 10]

In Example 1, except that 0.04 part of compound (A-a-1) and 0.03 part of compound (A-a-2) were used as the compound (A-a), 0.14 part of compound (A-b-1) was used as the compound (A-b), 0.04 part of compound (A-c-1) was used as the compound (A-c), and 0.04 part of the near-infrared absorbing dye (X-1) was used, a substrate including a transparent resin substrate including compound (A) and a near-infrared absorbing dye (X) was obtained in the same manner and under the same conditions as in Example 1. The spectral transmittance of an optical filter including this substrate was measured to evaluate the optical properties. In addition, a camera module was manufactured using the obtained optical filter, and color shading and ghosting of a camera image were evaluated. The results are shown in Fig. 14 and Table 15.

[Example 11]

In Example 1, a substrate including a transparent resin substrate was obtained by the same procedures and conditions as in Example 1, except that 0.04 part of compound (A-a-1) and 0.03 part of compound (A-a-2) were used as compound (A-a), 0.34 part of compound (A-b-1) was used as compound (A-b), and 0.04 part of compound (A-c-1) was used as compound (A-c).

A dielectric multilayer film (I) was formed as a first optical layer on one side of the obtained substrate, and an optical filter was obtained by additionally forming a similar dielectric multilayer film (I) on the other side of the substrate.

As a dielectric multilayer film (I), silica (SiO ₂ ) layers and titania (TiO ₂ ) layers were alternately laminated at a deposition temperature of 120°C (a total of 4 layers). The silica layers and titania layers of the dielectric multilayer film (I) were alternately laminated in the order of a titania layer, a silica layer, a titania layer, and a silica layer from the substrate side, and the outermost layer of the optical filter was made into a silica layer.

Here, the dielectric multilayer film (I) was a multilayer deposition film having a stacking number of 4, in which silica layers having a thickness of 33 to 88 nm and titania layers having a thickness of 13 to 111 nm were alternately stacked. The film composition is shown in Table 10 below.

[Table 10]

The optical properties were evaluated by measuring the spectral transmittance of the obtained substrate and optical filter. In addition, a camera module was manufactured using the obtained optical filter, and color shading and ghosting of the camera image were evaluated. The results are shown in Fig. 15 and Table 15.

[Examples 12 to 14]

A substrate was produced in the same manner as in Example 1, except that the drying conditions of the resin, solvent, resin substrate, and compound (A) were changed as shown in Table 15. The optical properties were evaluated by measuring the spectral transmittance of an optical filter including the substrate. In addition, a camera module was produced using the obtained optical filter, and color shading and ghosting of a camera image were evaluated. The results are shown in Table 15.

[Examples 15 and 16]

A substrate was produced in the same manner as in Example 2, except that the drying conditions of the resin, solvent, and resin substrate, the compound (A), and the near-infrared absorbing dye (X) were changed as shown in Table 15. The spectral transmittance of an optical filter including the substrate was measured to evaluate the optical properties. In addition, a camera module was produced using the obtained optical filter, and color shading and ghosting of a camera image were evaluated. The results are shown in Figs. 16 and 17 and Table 15.

[Comparative Example 1]

In Example 1, a substrate including a transparent resin substrate was obtained by the same procedures and conditions as in Example 1, except that 0.07 part of compound (Aa-1) was used as the compound (Aa) and 0.08 part of compound (Ab-1) was used as the compound (Ab). |X _b -X _a | of the obtained substrate was 61 nm, and less than 100 nm.

Subsequently, a dielectric multilayer film (II) comprising silica (SiO ₂ ) layers and titania (TiO ₂ ) layers alternately laminated as a first optical layer on one side of the obtained substrate (a total of 26 layers) was formed, and further, a dielectric multilayer film (III) comprising silica (SiO ₂ ) layers and titania (TiO ₂ ) layers alternately laminated as a second optical layer on the other side of the substrate (a total of 20 layers) was formed, thereby obtaining an optical filter having a thickness of approximately 0.105 mm.

The design of the genetic multilayer films (II) and (III) was performed as follows.

For the thickness and number of layers of each layer, optimization was performed using optical thin film design software (Essential Macleod, Thin Film Center) in accordance with the wavelength-dependent characteristics of the substrate refractive index or the absorption characteristics of the applied compound (A) so as to achieve an anti-reflection effect in the visible light range and selective transmission/reflection performance in the near-infrared range. When performing optimization, the input parameters (target values) to the software in this comparative example were as shown in Table 11 below.

[Table 11]

As a result of the film configuration optimization, the dielectric multilayer film (II) in Comparative Example 1 became a multilayer deposition film having a stacking number of 26, in which silica layers having a film thickness of 31 to 155 nm and titania layers having a film thickness of 10 to 94 nm were alternately laminated, and the dielectric multilayer film (III) became a multilayer deposition film having a stacking number of 20, in which silica layers having a film thickness of 38 to 189 nm and titania layers having a film thickness of 11 to 109 nm were alternately laminated. An example of a film configuration that was optimized is shown in Table 12 below.

[Table 12]

The optical properties were evaluated by measuring the spectral transmittance of the obtained optical filter. In addition, a camera module was manufactured using the obtained optical filter, and color shading and ghosting of the camera image were evaluated. The results are shown in Fig. 18 and Table 15. Although the optical filter obtained in Comparative Example 1 exhibited relatively good optical density, the decrease in transmittance at high angle incidence was large, and the occurrence of ghosting, which is thought to be caused by near-infrared reflection by the dielectric multilayer film, was confirmed, and furthermore, the color shading suppression effect was confirmed to be poor.

[Comparative Example 2]

A substrate including a transparent resin substrate was obtained by the same procedure and conditions as Comparative Example 1. On one side of the obtained substrate, a dielectric multilayer film (IV) in which silica (SiO ₂ ) layers and titania (TiO ₂ ) layers were alternately laminated (a total of 30 layers) as a first optical layer was formed, and further, on the other side of the substrate, a dielectric multilayer film (V) in which silica (SiO ₂ ) layers and titania (TiO ₂ ) layers were alternately laminated (a total of 20 layers) as a second optical layer was formed, thereby obtaining an optical filter having a thickness of approximately 0.105 mm.

When performing optimization, in this comparative example, the input parameters (target values) to the software were as shown in Table 13 below.

[Table 13]

As a result of the film configuration optimization, in Comparative Example 2, the dielectric multilayer film (IV) became a multilayer deposition film having a stacking number of 30, in which silica layers having a film thickness of 22 to 467 nm and titania layers having a film thickness of 6 to 130 nm were alternately laminated, and the dielectric multilayer film (V) became a multilayer deposition film having a stacking number of 20, in which silica layers having a film thickness of 84 to 206 nm and titania layers having a film thickness of 8 to 109 nm were alternately laminated. An example of a film configuration that was optimized is shown in Table 14 below.

[Table 14]

The optical properties were evaluated by measuring the spectral transmittance of the obtained optical filter. In addition, a camera module was manufactured using the obtained optical filter, and color shading and ghosting of the camera image were evaluated. The results are shown in Fig. 19 and Table 15. It was confirmed that the optical filter obtained in Comparative Example 2 had a large decrease in transmittance at high-angle incidence, and furthermore, the absorption in the near-infrared wavelength range was insufficient, so that the color shading suppression effect and ghost suppression effect were poor.

[Comparative Example 3]

A substrate including a transparent resin substrate was obtained by the same procedure and conditions as in Comparative Example 1. Subsequently, by the same procedure and conditions as in Example 11, a dielectric multilayer film (I) was formed as a first optical layer on one side of the obtained substrate, and further, a similar dielectric multilayer film (I) was formed on the other side of the substrate, thereby obtaining an optical filter having a thickness of approximately 0.101 mm.

The optical properties were evaluated by measuring the spectral transmittance of the obtained optical filter. In addition, a camera module was manufactured using the obtained optical filter, and color shading and ghosting of the camera image were evaluated. The results are shown in Fig. 20 and Table 15. It was confirmed that the optical filter obtained in Comparative Example 3 had insufficient absorption in the near-infrared wavelength range, and thus the ghost suppression effect was poor.

[Comparative Example 4]

A substrate including a transparent resin substrate was obtained by the same procedure and conditions as in Comparative Example 1. The spectral transmittance of an optical filter including this substrate was measured to evaluate the optical characteristics. In addition, a camera module was manufactured using the obtained optical filter, and color shading and ghosting of a camera image were evaluated. The results are shown in Fig. 21 and Table 15. It was confirmed that the optical filter obtained in Comparative Example 4 had insufficient absorption in the near-infrared wavelength range, and thus the ghost suppression effect was poor.

[Comparative Example 5]

A camera module was manufactured using only a cover member without using an optical filter, and color shading and ghosting of the camera image were evaluated. The results are shown in Table 15. Since the camera module obtained in Comparative Example 5 did not have an optical filter that absorbs the near-infrared region, it was confirmed that the degree of both color shading and ghosting was so severe that it was at an unacceptable level even for general camera module use.

[Table 15-1]

[Table 15-2]

The composition of the composition described in Table 15 above, symbols of various compounds, etc., and drying conditions of the film [(transparent) resin substrate or resin support] are as follows.

<Form of description>

Form (1): Transparent resin substrate containing compound (A)

Form (2): A transparent resin substrate containing a compound (A) having resin layers on both sides

Form (3): A transparent resin layer containing compound (A) on both sides of a resin support

Form (4): A transparent resin layer containing a compound (A) is provided on one side of a transparent glass substrate.

Form (5): A transparent resin layer containing compound (A) is provided on one side of a near-infrared absorbing glass substrate.

Form (6): A transparent resin substrate containing a compound (A) having an antireflection layer on both sides

Form (7): Transparent resin substrate comprising compound (A) and near-infrared absorbing pigment (X)

Form (8): A transparent resin substrate having a near-infrared reflective layer on both sides, wherein |X _b -X _a | comprises a compound (A) and is less than 100 nm (comparative example)

Form (9): Compound (A) containing |X _b -X _a | having an antireflection layer on both sides of a transparent resin substrate of less than 100 nm (comparative example)

Form (10): Transparent resin substrate containing compound (A), |X _b -X _a | of less than 100 nm (comparative example)

<Transparent Resin>

Resin A: Cylindrical polyolefin resin (resin synthesis example 1)

Resin B: Aromatic polyether resin (resin synthesis example 2)

Resin C: Polyimide resin (resin synthesis example 3)

Resin D: Fantasy olefin resin "Zeonoa 1420R" (manufactured by Nippon Zeon Co., Ltd.)

<Glass substrate>

Glass substrate (1): Transparent glass substrate "OA-10G (thickness 150㎛)" cut to a size of 60 mm in length and 60 mm in width (manufactured by Nippon Denki Glass Co., Ltd.)

Glass substrate (2): Near-infrared absorbing glass substrate "BS-11 (thickness 120㎛)" cut to a size of 60 mm in length and 60 mm in width (manufactured by Matsunami Glass Kogyo Co., Ltd.)

<Resin support>

Resin support (1): Transparent resin substrate containing resin A having a thickness of 0.1 mm, a length of 60 mm, and a width of 60 mm

<Near-infrared absorbing pigment>

≪Compound (A)≫

Compound (A-a-1): A compound represented by the formula (A-a-1) (maximum absorption wavelength 712 nm in dichloromethane)

Compound (A-a-2): A compound represented by the formula (A-a-2) (maximum absorption wavelength 686 nm in dichloromethane)

Compound (A-b-1): Compound represented by the formula (A-b-1) (maximum absorption wavelength 738 nm in dichloromethane)

Compound (A-c-1): Compound represented by the formula (A-c-1) (maximum absorption wavelength 776 nm in dichloromethane)

Compound (A-c-2): A compound represented by the formula (A-c-2) (maximum absorption wavelength 760 nm in dichloromethane)

Compound (A-c-3): A compound represented by the following formula (A-c-3) (maximum absorption wavelength 773 nm in dichloromethane)

≪Other pigments (X)≫

Near-infrared absorbing pigment (X-1): A compound represented by the formula (X-1) (maximum absorption wavelength 813 nm in dichloromethane)

Near-infrared absorbing pigment (X-2): A compound represented by the following formula (X-2) (maximum absorption wavelength 870 nm in dichloromethane)

<Solvent>

Solvent (1): Methylene chloride

Solvent (2): N,N-dimethylacetamide

Solvent (3): Cyclohexane/xylene (mass ratio: 7/3)

<Film drying conditions>

Condition (1): 20℃/8hr → Reduced pressure 100℃/8hr

Condition (2): 60℃/8hr→80℃/8hr→140℃/8hr under reduced pressure

Condition (3): 60℃/8hr→80℃/8hr→100℃/24hr under reduced pressure

Additionally, the coating was peeled off from the glass plate before drying under reduced pressure.

Condition (4): 80℃/2min

Condition (5): 70℃/2min

1, 1', 1'': light
2: Optical Filter
3: Spectrophotometer
111: Camera image
112: Whiteboard
113: Example of the central part of a white board
114: Example of a short section of a white board
121: Camera image
122: Light source
123: Example of ghosts around a light source
200: Camera device
210: Absence of cover
220: Lens group
230: Aperture
240: Optical Filter
250: Solid State Imaging Device
260: Housing

Claims (13)

An optical filter satisfying the following requirements (a), (b), (e) and (f):
(a) In a region of a wavelength of 430 to 580 nm, the minimum value T _b-0 of the transmittance of light incident from a vertical direction of the optical filter, the minimum value T _b-30 of the transmittance of light incident from a direction obliquely 30 degrees to the vertical direction, and the minimum value T _b-60 of the transmittance of light incident from a direction obliquely 60 degrees to the vertical direction are all 55% or more and less than 90%;
(b) In a region of a wavelength of 700 to 780 nm, the average value OD _a-0 of the optical density for light incident from a direction perpendicular to the optical filter, the average value OD _a-30 of the optical density for light incident from a direction oblique to 30 degrees with respect to the vertical direction, and the average value OD _{a-60 of the optical density for light incident from a direction oblique to} 60 degrees with respect to the vertical direction are all 1.8 or more;
(e) has a layer comprising a compound (A) having an absorption maximum in a wavelength range of 650 to 800 nm;
(f) The absolute value of the difference |X b - X a | between the wavelength X _a on the longest wavelength side, which has a transmittance for light incident from the vertical direction of the substrate of more than 10% and less than or equal to 10% from the short wavelength side to the long wavelength side, and the wavelength X _b on the shortest wavelength side, which has a transmittance for light incident from the vertical direction of the substrate of less than or equal to 10% and more than 10% from the short wavelength side to the _{long wavelength} side, is 125 nm or more. In the first paragraph, an optical filter further satisfying the following requirement (c):
(c) In the range of wavelengths from 900 to 1,200 nm, the average value of transmittance T _IR of light incident from the vertical direction of the optical filter is 60% or more. An optical filter according to claim 1 or 2, further satisfying the following requirement (d):
(d) In a region of a wavelength of 430 to 580 nm, the average value T _a-0 of the transmittance of light incident from a vertical direction of the optical filter, the average value T _a-30 of the transmittance of light incident from a direction obliquely 30 degrees to the vertical direction, and the average value T _a-60 of the transmittance of light incident from a direction obliquely 60 degrees to the vertical direction are all 65% or more and less than 90%. An optical filter according to claim 1, characterized in that the compound (A) is at least one compound selected from the group consisting of a squarylium-based compound, a phthalocyanine-based compound, a naphthalocyanine-based compound, a croconium-based compound, and a cyanine-based compound. An optical filter characterized in that in claim 1, the substrate contains, as the compound (A), a compound (A-a) having an absorption maximum in a range of a wavelength exceeding 650 nm to 715 nm, a compound (A-b) having an absorption maximum in a range of a wavelength exceeding 715 nm to 750 nm, and a compound (A-c) having an absorption maximum in a range of a wavelength exceeding 750 nm to 800 nm. An optical filter in claim 1, wherein the layer containing the compound (A) is a transparent resin layer. In claim 6, an optical filter characterized in that the resin constituting the transparent resin layer is at least one resin selected from the group consisting of a cyclic polyolefin resin, an aromatic polyether resin, a polyimide resin, a fluorene polycarbonate resin, a fluorene polyester resin, a polycarbonate resin, a polyamide resin, an aramid resin, a polysulfone resin, a polyethersulfone resin, a polyparaphenylene resin, a polyamideimide resin, a polyethylene naphthalate resin, a fluorinated aromatic polymer resin, a (modified) acrylic resin, an epoxy resin, a silsesquioxane ultraviolet-curable resin, a maleimide resin, an alicyclic epoxy thermosetting resin, a polyether ether ketone resin, a polyarylate resin, an allyl ester curable resin, an acrylic ultraviolet-curable resin, a vinyl ultraviolet-curable resin, and a resin containing silica formed by a sol-gel method. An optical filter in claim 6, wherein the refractive index (n20d) of the resin constituting the transparent resin layer is 1.50 to 1.53. A camera module characterized by having an optical filter as described in claim 1 or claim 2. A camera module according to claim 9, characterized in that it has a cover member that protects the internal mechanism of the camera module from the outside, and the cover member has a near-infrared reflection function. An electronic device characterized by having a camera module as described in claim 9. delete delete

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