JP6578718B2 - Optical filter and device using optical filter - Google Patents

Description

  The present invention relates to an optical filter and an apparatus using the optical filter. Specifically, the present invention relates to an optical filter (two-wavelength bandpass filter) that selectively transmits visible light and part of near infrared light, and a solid-state imaging device and a camera module using the optical filter.

  A solid-state imaging device such as a video camera, a digital still camera, a mobile phone with a camera function, or a smartphone uses a CCD or CMOS image sensor, which is a solid-state imaging device for color images. However, silicon photodiodes having sensitivity to near infrared rays that cannot be detected by human eyes are used. These solid-state image sensors need to be corrected for visibility so that they appear natural to the human eye. Optical filters that selectively transmit or cut light in a specific wavelength region (for example, near-infrared cut) Filter) is often used.

  As such a near-infrared cut filter, what was conventionally manufactured by various methods is used. For example, Patent Document 1 describes a near-infrared cut filter using a substrate made of a transparent resin and containing a near-infrared absorber in the transparent resin, and Patent Document 2 describes a glass substrate containing copper ions. A near-infrared cut filter using is described.

  On the other hand, in recent years, an attempt has been made to provide a camera module with a sensing function such as motion capture using near infrared rays or distance recognition (space recognition). In such an application, it is necessary to selectively transmit visible light and part of near infrared rays, so that it is not possible to use a near infrared cut filter that uniformly blocks near infrared rays as in the prior art.

  As an optical filter that selectively transmits visible light and some near-infrared rays, Toa Riken Laboratories Co., Ltd. and Ceratech Japan Co., Ltd. sell filters with a dielectric multilayer film on a glass substrate. Yes.

JP-A-6-200113 Japanese Patent No. 5036229

  An optical filter that is commercially available as an optical filter that selectively transmits visible light and part of near infrared light has a problem in that spectral characteristics change greatly when light enters the filter obliquely. In particular, if the incident angle dependence of the optical filter is large on the long wavelength side of the visible light transmission band or the short wavelength side of the near infrared selective transmission band, the near infrared rays used for the sensing function when the light beam is incident from an oblique direction of the filter. In addition to the deterioration in signal-to-noise ratio (S / N ratio), there are problems such as adverse effects on camera image quality and color reproducibility at image edges. FIG. 1 shows an example of the spectral transmission spectrum of a conventional two-wavelength bandpass filter. However, when the incident angle reaches 30 °, the near-infrared selective transmission band is greatly shifted to the short wavelength side and is essentially cut off. It is confirmed that the transmittance in the power wavelength region (near 750 to 800 nm in the example of this figure) becomes high. Therefore, the near-infrared selective transmission band has little dependency on the incident angle on the short wavelength side, and good near-infrared ray S / N ratio, camera image quality, selective transmission of visible rays and some near-infrared rays. An optical filter that satisfies all of the characteristics has been desired.

  An object of the present invention is to provide an optical filter having a function of selectively transmitting visible light and part of near-infrared light and having little incident angle dependency, and an apparatus using the optical filter. .

As a result of intensive studies to achieve the above problems, the present inventors can solve the above problems by using an optical filter having specific optical characteristics, particularly on the short wavelength side of the near infrared selective transmission band. The inventors have found that the dependence on the incident angle can be reduced, and have completed the present invention.
Examples of embodiments of the present invention are shown below.

[1] An optical filter that selectively transmits visible light and some near infrared rays,
A region having a wavelength of 650 nm or more has a light blocking band Za, a light transmitting band Zb, and a light blocking band Zc, and the center wavelength of each band is Za <Zb <Zc,
Optical at a wavelength of 800 nm when measured from the vertical direction of the optical filter is 20% or less, and when measured from a direction at 30 ° to the vertical direction of the optical filter, the transmittance is 50% or less. filter.

  [2] In the wavelength region of 700 to 800 nm, the average transmittance when measured from the vertical direction of the optical filter is 5% or less, and when measured from a direction of 30 ° with respect to the vertical direction of the optical filter. The optical filter according to [1], wherein an average transmittance is 10% or less.

[3] Among Zb, the wavelength value (Xa) on the shortest wavelength side and the wavelength value (Xb) on the longest wavelength side when the transmittance is 50% when measured from the vertical direction of the optical filter The optical filter according to [1] or [2], wherein the difference Xb−Xa is 5 to 150 nm, and the Y value represented by Y = (Xa + Xb) / 2 is 820 to 950 nm.
[4] Of the Zb, the wavelength value (Xa) on the shortest wavelength side, which has a transmittance of 50% when measured from the vertical direction of the optical filter, is 810 to 900 nm, [1] to [3 ] The optical filter in any one of.

  [5] The minimum transmittance when measured from the vertical direction of the optical filter in Za and Zc is 4% or less, and the maximum transmittance when measured from the vertical direction of the optical filter in Zb is 55% or more. The optical filter according to any one of [1] to [4].

  [6] The optical filter according to any one of [1] to [5], wherein an average transmittance measured from the vertical direction of the optical filter in a wavelength range of Y-10 nm to Y + 10 nm is 60% or more.

[7] The optical filter includes a substrate (i), and the substrate (i) includes a transparent resin layer containing a compound (S) having an absorption maximum at a wavelength of 750 to 850 nm. 6] The optical filter according to any one of the above.
[8] The optical filter according to [7], wherein the compound (S) is a compound represented by the following formula (S1).

[In the formula (S1), X independently represents an oxygen atom, a sulfur atom, a selenium atom, a tellurium atom or —NR ⁸ —;
R ^{1 to} R ⁸ are each independently a hydrogen atom, a halogen atom, a sulfo group, a hydroxyl group, a cyano group, a nitro group, a carboxy group, a phosphate group, a —NR ^g R ^h group, a —SO ₂ R ⁱ group, or —OSO. It represents either ₂ R ⁱ group or a group represented by L ^a ~L ^h, are each R ^g and R ^h independently represent any of hydrogen atom, -C (O) R ⁱ groups or the following L ^a ~L ^e , R ⁱ represents any of the following L ^a ~L ^e,
(L ^a ) an aliphatic hydrocarbon group having 1 to 12 carbon atoms (L ^b ) a halogen-substituted alkyl group having 1 to 12 carbon atoms (L ^c ) an alicyclic hydrocarbon group having 3 to 14 carbon atoms (L ^d ) carbon the number 6 to 14 aromatic hydrocarbon group (L ^e) carbon atoms, which may have a number Hajime Tamaki 3 to 14 (L ^f) an alkoxy group having 1 to 12 carbon atoms (L ^g) substituents L carbon 1 to 12 acyl groups,
(L ^h ) an alkoxycarbonyl group having 1 to 12 carbon atoms that may have a substituent L. The substituent L is an aliphatic hydrocarbon group having 1 to 12 carbon atoms, a halogen-substituted alkyl group having 1 to 12 carbon atoms, It is at least one selected from the group consisting of an alicyclic hydrocarbon group having 3 to 14 carbon atoms, an aromatic hydrocarbon group having 6 to 14 carbon atoms and a heterocyclic group having 3 to 14 carbon atoms. ]

  [9] The optical filter according to [7] or [8], wherein the transparent resin layer includes a compound (A) having an absorption maximum at a wavelength of 600 nm or more and less than 750 nm in addition to the compound (S).

  [10] The transparent resin layer is a cyclic (poly) olefin resin, an aromatic polyether resin, a polyimide resin, a fluorene polycarbonate resin, a fluorene polyester resin, a polycarbonate resin, a polyamide resin, or a polyarylate resin. , Polysulfone resin, polyethersulfone resin, polyparaphenylene resin, polyamideimide resin, polyethylene naphthalate resin, fluorinated aromatic polymer resin, (modified) acrylic resin, epoxy resin, allyl ester [7] to [9], including at least one resin selected from the group consisting of a system curable resin, a silsesquioxane UV curable resin, an acrylic UV curable resin, and a vinyl UV curable resin. The optical filter according to any one of the above.

  [11] The optical filter according to any one of [7] to [10], which has a dielectric multilayer film on at least one surface of the substrate (i).

[12] The optical filter according to any one of [1] to [11], which is for a solid-state imaging device.
[13] A solid-state imaging device including the optical filter according to any one of [1] to [12].
[14] A camera module comprising the optical filter according to any one of [1] to [12].

  According to the present invention, it is possible to provide an optical filter that is excellent in transmission characteristics of visible light and part of near-infrared light and that is less dependent on incident angle.

FIG. 1 shows an example of a spectral transmission spectrum of a conventional two-wavelength bandpass filter. FIG. 2A is a schematic diagram illustrating a method for measuring the transmittance when measured from the vertical direction of the optical filter. FIG. 2B is a schematic diagram illustrating a method of measuring the transmittance when measured from an angle of 30 ° with respect to the vertical direction of the optical filter. FIG. 3 is a spectral transmission spectrum of the substrate obtained in Example 1. FIG. 4 is a spectral transmission spectrum of the optical filter obtained in Example 1. FIG. 5 is a spectral transmission spectrum of the substrate obtained in Example 2. FIG. 6 is a spectral transmission spectrum of the optical filter obtained in Example 2. FIG. 7 is a spectral transmission spectrum of the optical filter obtained in Comparative Example 1. FIG. 8 is a spectral transmission spectrum of the optical filter obtained in Comparative Example 2.

  Hereinafter, the present invention will be specifically described.

≪Optical filter≫
The optical filter of the present invention is a filter that selectively transmits visible light and some near infrared rays, and has a light blocking band Za, a light transmitting band Zb, and a light blocking band Zc in a region having a wavelength of 650 nm or more. The center wavelength of each band is Za <Zb <Zc, the transmittance when measured from the vertical direction of the optical filter at a wavelength of 800 nm is 20% or less, and the direction is 30 ° with respect to the vertical direction of the optical filter. It is an optical filter whose transmittance | permeability when measured from is 50% or less. Such an optical filter of the present invention is excellent in the transmittance characteristics of visible light and part (desired region) of near-infrared light, and further has little dependence on the incident angle, particularly on the short wavelength side of the near-infrared selective transmission band. It is an optical filter with little incident angle dependency.

  The optical filter of the present invention has a transmittance of 20% or less when measured from the vertical direction of the optical filter at a wavelength of 800 nm, and the filter is used for a solid-state imaging device having a near infrared sensing function. Is more preferably 15% or less, still more preferably 10% or less, and particularly preferably 5% or less. Further, the transmittance when measured from a direction of 30 ° with respect to the vertical direction of the optical filter at a wavelength of 800 nm is 50% or less, preferably 40% or less, more preferably 30% or less, and particularly preferably 20 % Or less. Since the optical filter of the present invention has the above-mentioned optical characteristics, it has excellent transmittance characteristics of visible light and part (desired region) of near-infrared light, and has little dependence on the incident angle, particularly a short near-infrared selective transmission band. An optical filter with little dependence on the incident angle on the wavelength side can be obtained, and light with an unnecessary wavelength can be effectively cut, and the color reproducibility of the obtained camera image can be improved.

The optical filter of the present invention preferably suppresses the transmittance at a wavelength of 700 to 800 nm, and the filter is used for a device having a sensor, for example, a solid-state imaging device by reducing the transmittance in this wavelength region. In this case, it is considered that noise detected in the sensor is reduced. For this reason, it is considered preferable that the transmittance at a wavelength of 800 nm is low, but the conventional optical filter cannot achieve a low transmittance at a wavelength of 800 nm. In particular, when the incident angle of light incident on a conventional optical filter changes (for example, 30 ° with respect to the vertical direction of the filter surface), the transmittance at a wavelength of 800 nm usually increases. It cannot be used for applications where light may be incident from an angle and where noise reduction is required.
On the other hand, according to the optical filter of the present invention, the transmittance at a wavelength of 700 to 800 nm can be kept low, and even if the angle incident on the filter changes, the transmittance at a wavelength of 800 nm is low. Therefore, it can be used particularly suitably for applications where there is a possibility that light may enter from the light source and where noise reduction is required.

  The optical filter of the present invention has a light blocking band Za, a light transmitting band Zb, and a light blocking band Zc in a region having a wavelength of 650 nm or more. However, the center wavelength of each band is Za <Zb <Zc.

  Za has a wavelength of 650 nm or more and 900 nm or less, and the transmittance when measured from the vertical direction of the optical filter is from the shortest wavelength Za1 that is more than 20% to 20% or less, and the longest wavelength that is less than 20% to 20% or more. The wavelength band up to Za2. The central wavelength of Za is (Za1 + Za2) / 2 nm.

  Zb is the longest wavelength from 40% or less to 40% or less, and the longest wavelength from 40% or less to 40% or less when measured from the vertical direction of the optical filter at wavelengths of 750 nm or more and 1050 nm or less. The wavelength band up to Zb2. The central wavelength of Zb is (Zb1 + Zb2) / 2 nm.

  Zc refers to a wavelength band from the shortest wavelength Zc1 at which the transmittance when measured from the vertical direction of the optical filter is greater than 20% to 20% or less at a wavelength of 820 nm or more, to a wavelength Zc2 that is Zc1 + 200 nm. The central wavelength of Zc is (Zc1 + Zc2) / 2 nm.

  When the optical filter of the present invention is used for a solid-state imaging device having a near-infrared sensing function, the maximum transmittance of the light ray (near-infrared) transmission band Zb is preferably higher, and the minimum transmission of the light-rejection bands Za and Zc. A lower rate is preferred. In such a case, the solid-state imaging device or the like having the optical filter of the present invention can achieve excellent near-infrared sensing performance and can effectively cut off light with an unnecessary wavelength, so that color reproduction is possible. It is possible to obtain a camera image having excellent properties.

  The maximum transmittance when measured from the vertical direction of the optical filter in the light transmission band Zb is preferably 55% or more, more preferably 57% or more, still more preferably 60% or more, and particularly preferably 63% or more. The minimum transmittance when measured from the vertical direction of the optical filter in the light blocking zones Za and Zc is preferably 4% or less, more preferably 3% or less, still more preferably 2% or less, and particularly preferably 1% or less. . If the maximum transmittance in Zb and the minimum transmittance in Za and Zc are within the above ranges, the solid-state imaging device having the optical filter of the invention achieves high near-infrared sensing performance and reduces noise, so color reproduction It is possible to obtain an excellent camera image.

  Of the Zb, the difference Xb between the wavelength value (Xa) on the shortest wavelength side and the wavelength value (Xb) on the longest wavelength side, at which the transmittance is 50% when measured from the vertical direction of the optical filter. The width of the light transmission zone Zb can be defined by -Xa, and the value of Xb-Xa is preferably 5 to 150 nm, more preferably 10 to 140 nm, and particularly preferably 15 to 130 nm. Moreover, the value of Y represented by Y = (Xa + Xb) / 2 is preferably 820 to 950 nm, more preferably 825 to 920 nm, still more preferably 830 to 890 nm, and particularly preferably 835 to 880 nm. If the values of Xb-Xa and Y are in this range, an optical filter that is superior in near-infrared sensing sensitivity and color reproducibility of the camera image can be obtained.

  The Xa is preferably in the range of 810 to 900 nm, more preferably 810 to 860 nm, and particularly preferably 810 to 840 nm. When Xa is within this range, it is preferable because desired light can be transmitted and blocked in the near infrared region, and noise can be reduced.

  The optical filter of the present invention has a transmittance curve measured from an angle of 30 ° with respect to the vertical direction of the optical filter, and has a wavelength on the shortest wavelength side where the transmittance is 50% in the band corresponding to Zb. The absolute value | Xa−Xa ′ | of the difference between the value (Xa ′) and Xa is preferably 30 nm or less, more preferably 25 nm or less, still more preferably 20 nm or less, and particularly preferably 15 nm or less. If the value of | Xa−Xa ′ | is within this range, an optical filter having a small incident angle dependency of the spectral characteristics can be obtained. When the optical filter is used in a camera module having a sensing function, the light can be obtained. A good near infrared S / N ratio and camera image quality can be achieved at the same time even if the filter is incident obliquely.

In the optical filter of the present invention, with respect to Y, the average transmittance when measured from the vertical direction of the optical filter in the wavelength region of Y-10 nm to Y + 10 nm is preferably 60% or more, more preferably 65% or more, and further preferably Is 70% or more, particularly preferably 80% or more.
A filter having such transmission characteristics can achieve high light transmission characteristics in the visible range and the target near-infrared range, and can achieve both a camera function and a near-infrared sensing function at a good level.

  When the optical filter of the present invention is used for a solid-state imaging device having a near-infrared sensing function, the average value of transmittance when measured from the vertical direction of the optical filter in the wavelength region of 700 to 800 nm is preferably 5% or less, more preferably 4% or less, further preferably 3% or less, further preferably 2% or less, particularly preferably 1% or less, when measured from a direction of 30 ° with respect to the vertical direction of the optical filter The average value of the transmittance is preferably 10% or less, more preferably 8% or less, further preferably 6% or less, still more preferably 5% or less, and particularly preferably 3% or less. When the optical filter of the present invention has such optical characteristics, it is possible to effectively cut off light beams having unnecessary wavelengths and improve the color reproducibility of camera images. In particular, light is applied to the filter. Even if it is made incident from an oblique direction, an optical filter having these effects is obtained.

  When the optical filter of the present invention is used for a solid-state imaging device or the like, it is preferable that the visible light transmittance is high. Specifically, in the wavelength range of 430 to 580 nm, the average transmittance when measured from the vertical direction of the optical filter is preferably 75% or more, more preferably 80% or more, still more preferably 83% or more, particularly preferably. Is 85% or more. When the average transmittance is within this range in this wavelength region, excellent imaging sensitivity can be achieved when the optical filter of the present invention is used as a solid-state imaging device.

  The optical filter of the present invention has the shortest wavelength value (Xd) at which the transmittance when measured from the vertical direction of the optical filter is 50% in the wavelength range of 560 to 800 nm and the vertical direction of the optical filter. The absolute value of the difference from the shortest wavelength value (Xe) at which the transmittance when measured from an angle of 30 ° is 50% is preferably small, specifically, preferably less than 25 nm, more preferably 15 nm. Is less than 10 nm, particularly preferably less than 10 nm. According to the optical filter having such optical characteristics, it is possible to obtain an optical filter with a small viewing angle dependency of the spectral characteristics and a wide viewing angle. Especially when used for applications such as a camera module, Color reproducibility at the edge of the image can be achieved.

The thickness of the optical filter of the present invention may be appropriately selected according to the desired application. However, according to the recent trend of thinning and weight reduction of solid-state imaging devices, the thickness of the optical filter of the present invention is also thin. Is preferred.
The thickness of the optical filter of the present invention is, for example, 260 μm or less, preferably 210 μm or less, more preferably 160 μm or less, further preferably 120 μm or less, particularly preferably 90 μm or less, and the lower limit is not particularly limited, but for example, 20 μm It is desirable to be.

<Optical filter structure, etc.>
Although the structure of the optical filter of the present invention is not particularly limited, it has a transparent resin layer containing the following compound (S) from the viewpoint that it can be thinned and an optical filter having the optical characteristics can be easily obtained. The substrate (i) is preferably contained, and the substrate (i) and the dielectric multilayer film are preferably included. In addition, the optical filter of the present invention may include other functional films depending on the desired application, required characteristics, and the like.

[Substrate (i)]
The base material (i) may be a single layer or a multilayer, and may have a transparent resin layer containing at least one of the following compounds (S). When the base material (i) is a single layer, for example, a base material made of a transparent resin substrate (ii) containing the compound (S) can be mentioned, and this transparent resin substrate (ii) is the transparent resin layer. It becomes. In the case of a multilayer, for example, an overcoat layer made of a curable resin containing the compound (S) on a support such as a glass support or a base resin support or a transparent resin substrate (ii), etc. Examples include a base material on which a transparent resin layer is laminated, and a base material on which a resin layer such as an overcoat layer made of a curable resin is laminated on a transparent resin substrate (ii) containing the compound (S). . From the viewpoints of manufacturing cost and ease of optical property adjustment, and further, it is possible to achieve a scratch-removing effect on the resin support and the transparent resin substrate (ii) and the improvement of scratch resistance of the substrate (i). A substrate in which a resin layer such as an overcoat layer made of a curable resin is laminated on a transparent resin substrate (ii) containing) is particularly preferable.
Hereinafter, the layer containing the compound (S) and the transparent resin is also referred to as “transparent resin layer”, and the other resin layers are also simply referred to as “resin layers”.

The lowest transmittance (Tb) measured from the vertical direction of the substrate (i) in the wavelength region of 750 nm or more is preferably 40% or less, more preferably 25% or less, and particularly preferably 10% or less.
The shortest wavelength (Xf) at which the transmittance measured from the vertical direction of the base material (i) in the wavelength region of 750 nm or more is less than 50% to 50% or more is preferably 770 to 900 nm, more preferably 775 to 890 nm. Especially preferably, it is 780-880 nm.
If the optical properties of (Tb) and (Xf) of the base material (i) are in such a range, unnecessary near infrared rays in the vicinity of the near infrared selective transmission band can be selectively and efficiently cut. The near infrared S / N ratio can be improved, and when the dielectric multilayer film is formed on the base material (i), the incident angle dependency of the optical characteristics on the short wavelength side of the near infrared selective transmission band can be reduced. it can.

In the region of wavelength 600 nm or more and less than 750 nm, the lowest transmittance (Ta) measured from the vertical direction of the substrate (i) is preferably 45% or less, more preferably 25% or less, and particularly preferably 10% or less. is there.
The shortest wavelength (Xc) at which the transmittance measured from the vertical direction of the substrate (i) in the region of a wavelength of 600 nm or more is more than 50% to 50% or less is preferably 610 to 705 nm, more preferably 620 to 680 nm. Especially preferably, it is 630-660 nm.
If the optical characteristics of (Ta) and (Xc) of the base material (i) are in such a range, unnecessary near infrared rays can be selectively and efficiently cut, and dielectric on the base material (i). When the multilayer film is formed, it is possible to reduce the incident angle dependency of the optical characteristics in the visible region to near the near infrared wave.

  The average transmittance of the substrate (i) at a wavelength of 430 to 580 nm is preferably 75% or more, more preferably 78% or more, and particularly preferably 80% or more. When a substrate having such transmission characteristics is used, high light transmission characteristics can be achieved in the visible range and the target near-infrared range, and both the camera function and the near-infrared sensing function can be achieved at a good level. .

The thickness of the base material (i) can be appropriately selected according to a desired application and is not particularly limited, but it is desirable and preferable to appropriately select so as to reduce the incident angle dependency of the obtained optical filter. Is 10 to 210 μm, more preferably 20 to 150 μm, still more preferably 20 to 110 μm, and particularly preferably 30 to 80 μm.
When the thickness of the substrate (i) is in the above range, the optical filter using the substrate (i) can be thinned and reduced in weight, and is preferably used for various applications such as a solid-state imaging device. it can. In particular, when the base material (i) made of the transparent resin substrate (ii) is used in a lens unit such as a camera module, it is preferable because the lens unit can be reduced in height and weight.

<Compound (S)>
The compound (S) is a compound having an absorption maximum at a wavelength of 750 to 850 nm, and preferably a squarylium compound represented by the following formula (S1). By using such a compound (S), the obtained base material (i) can simultaneously achieve sharp absorption near the absorption maximum and high visible light transmittance. Further, when a general organic dye is used for an optical filter, fluorescence is usually generated in many cases. However, as a result of intensive studies by the applicant, the fluorescence intensity that can be generated is significantly reduced by using the compound (S). It was found that it can be suppressed. Therefore, when the optical filter of the present invention having the substrate (i) containing the compound (S) is used for a camera module having a near-infrared sensing function, malfunction of the sensing function due to dye fluorescence can be prevented. .

In the formula (S1), X independently represents an oxygen atom, a sulfur atom, a selenium atom, a tellurium atom or —NR ⁸ —.
R ^{1 to} R ⁸ are each independently a hydrogen atom, a halogen atom, a sulfo group, a hydroxyl group, a cyano group, a nitro group, a carboxy group, a phosphate group, a —NR ^g R ^h group, a —SO ₂ R ⁱ group, or —OSO. It represents either ₂ R ⁱ group or a group represented by L ^a ~L ^h, are each R ^g and R ^h independently represent any of hydrogen atom, -C (O) R ⁱ groups or the following L ^a ~L ^e , R ⁱ represents any of the following L ^a ~L ^e.
(L ^a ) an aliphatic hydrocarbon group having 1 to 12 carbon atoms (L ^b ) a halogen-substituted alkyl group having 1 to 12 carbon atoms (L ^c ) an alicyclic hydrocarbon group having 3 to 14 carbon atoms (L ^d ) carbon the number 6 to 14 aromatic hydrocarbon group (L ^e) carbon atoms, which may have a number Hajime Tamaki 3 to 14 (L ^f) an alkoxy group having 1 to 12 carbon atoms (L ^g) substituents L carbon 1 to 12 acyl groups,
(L ^h ) an alkoxycarbonyl group having 1 to 12 carbon atoms that may have a substituent L. The substituent L is an aliphatic hydrocarbon group having 1 to 12 carbon atoms, a halogen-substituted alkyl group having 1 to 12 carbon atoms, It is at least one selected from the group consisting of an alicyclic hydrocarbon group having 3 to 14 carbon atoms, an aromatic hydrocarbon group having 6 to 14 carbon atoms and a heterocyclic group having 3 to 14 carbon atoms.

R ¹ is preferably a hydrogen atom, chlorine atom, fluorine atom, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, cyclohexyl group, phenyl group. Group, hydroxyl group, amino group, dimethylamino group and nitro group, more preferably hydrogen atom, chlorine atom, fluorine atom, methyl group, ethyl group, n-propyl group, isopropyl group and hydroxyl group.

R ^{2 to} R ⁷ are preferably each independently a hydrogen atom, chlorine atom, fluorine atom, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl. Group, cyclohexyl group, phenyl group, hydroxyl group, amino group, dimethylamino group, diethylamino group, cyano group, nitro group, acetylamino group, propionylamino group, N-methylacetylamino group, trifluoromethanoylamino group, pentafluoro Ethanoylamino group, t-butanoylamino group, cyclohexanoylamino group, n-butylsulfonyl group, morpholino group, methylcarbonyl group, trifluoromethylcarbonyl group, tert-butylcarbonyl group, more preferably a hydrogen atom , Chlorine atom, fluorine atom, methyl group, ethyl group, -Propyl group, isopropyl group, tert-butyl group, hydroxyl group, dimethylamino group, diethylamino group, nitro group, acetylamino group, propionylamino group, trifluoromethanoylamino group, pentafluoroethanoylamino group, t-butanoyl An amino group, a cyclohexanoylamino group, and a morpholino group;

R ⁸ 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, a cyclohexyl group, or a phenyl group, and more preferably Are a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, and a tert-butyl group.

  X is preferably an oxygen atom or a sulfur atom, and particularly preferably an oxygen atom.

  The compound (S) can also represent the structure by a description method such as the following formula (S2), in addition to a description method such as the following formula (S1). That is, the difference between the following formula (S1) and the following formula (S2) is only the structure description method, and both represent the same compound. In the present invention, unless otherwise specified, the structure of the squarylium compound is represented by a description method such as the following formula (S1).

  Furthermore, for example, the compound represented by the following formula (S1) and the compound represented by the following formula (S3) can be regarded as the same compound.

  The structure of the compound (S) is not particularly limited as long as it satisfies the requirement of the formula (S1). The left and right substituents bonded to the central four-membered ring may be the same or different, but the same is preferable because it is easy to synthesize. Specific examples of the compound (S) include compounds (s-1) to (s-30) described in Table 1 below.

The absorption maximum wavelength of the compound (S) is preferably 755 nm to 845 nm, more preferably 760 nm to 840 nm, and particularly preferably 765 nm to 835 nm. When the absorption maximum wavelength of the compound (S) is in such a range, unnecessary near infrared rays in the vicinity of the near infrared selective transmission band can be selectively and efficiently cut.
In the present invention, the absorption maximum wavelength of a compound is, for example, the wavelength at which absorption is maximized when the transmittance of a solution obtained by dissolving the compound in a good solvent is measured (optical path length 1 cm). Observed.

  Compound (S) may be synthesized by a generally known method. For example, JP-A-1-228960, JP-A-2001-40234, JP-A-3094037, and JP-A-3196383 It can be synthesized with reference to the method described.

The content of the compound (S) is, for example, a substrate made of a transparent resin substrate (ii) containing the compound (S) or a transparent resin substrate containing the compound (S) as the substrate (i). (Ii) When using a base material on which a resin layer such as an overcoat layer made of a curable resin or the like is laminated, preferably 0.01 to 2.0 parts by weight with respect to 100 parts by weight of the transparent resin. , More preferably 0.02 to 1.5 parts by weight, particularly preferably 0.03 to 1.0 parts by weight. As the base material (i), a compound is used as a glass support or a resin support as a base. In the case of using a base material on which a transparent resin layer such as an overcoat layer made of a curable resin containing (S) is used, with respect to 100 parts by weight of the resin forming the transparent resin layer containing the compound (S) Preferably 0.1 to 5.0 parts by weight, more preferably Is 0.2 to 4.0 parts by weight, particularly preferably 0.3 to 3.0 parts by weight. When the content of the compound (S) is within the above range, an optical filter having both good near-infrared absorption and transmission characteristics and high visible light transmittance can be obtained.
As a compound (S) used for the said base material (i), 1 type may be sufficient and 2 or more types may be sufficient.

<Compound (A)>
In addition to the compound (S), the substrate (i) may further contain a compound (A) having an absorption maximum at a wavelength of 600 nm or more and less than 750 nm.

When the compound (A) and the compound (S) are used in combination, these compounds may be contained in the same layer or in different layers. When they are contained in the same layer, for example, the compound (A) and the compound (S) are both contained in the same transparent resin substrate (ii) and on a support such as a glass support. The base material by which the transparent resin layer containing (A) and a compound (S) is laminated | stacked can be mentioned, When it is contained in a separate layer, for example on the resin-made board | substrates containing a compound (A) The resin layer containing the compound (A) is laminated on the base material on which the transparent resin layer containing the compound (S) is laminated, or the transparent resin substrate (ii) containing the compound (S). A substrate can be mentioned.
More preferably, the compound (A) and the compound (S) are contained in the same layer. In such a case, the compound (A) and the compound ( It becomes easier to control the content ratio with S).

The compound (A) is not particularly limited as long as it has an absorption maximum at a wavelength of 600 nm or more and less than 750 nm, but is preferably a solvent-soluble dye compound, and is a group consisting of a squarylium compound, a phthalocyanine compound, and a cyanine compound. More preferably, it is at least one selected from the above, more preferably contains a squarylium compound, more preferably contains at least one squarylium compound and another compound (A), and other compound (A). Particularly preferred are phthalocyanine compounds and cyanine compounds.
The squarylium-based compound has excellent visible light permeability, steep absorption characteristics, and a high molar extinction coefficient, but may generate fluorescence that causes scattered light upon light absorption. In such a case, by using a combination of the squarylium compound and the other compound (A), it is possible to obtain better camera image quality with less scattered light.

  The absorption maximum wavelength of the compound (A) is preferably 620 nm to 748 nm, more preferably 650 nm to 745 nm, and particularly preferably 660 nm to 740 nm. When the substrate (i) contains the compound (A) in addition to the compound (S), the dependency on the incident angle in the visible region in addition to the short wavelength side of the near-infrared selective transmission band can be reduced. ) And (Xe), it is easier to reduce the absolute value of the difference.

  The content of the compound (A) is, for example, a substrate made of a transparent resin substrate (ii) containing the compound (A) or a transparent resin substrate containing the compound (A) as the substrate (i). (Ii) When using a base material on which a resin layer such as an overcoat layer made of a curable resin or the like is laminated, preferably 0.01 to 2.0 parts by weight with respect to 100 parts by weight of the transparent resin. , More preferably 0.02 to 1.5 parts by weight, particularly preferably 0.03 to 1.0 parts by weight. As the base material (i), a compound is used as a glass support or a resin support as a base. In the case of using a base material on which a transparent resin layer such as an overcoat layer made of a curable resin containing (A) is used, 100 parts by weight of the resin forming the transparent resin layer containing the compound (A) Preferably 0.1 to 5.0 parts by weight, more preferably Is 0.2 to 4.0 parts by weight, particularly preferably 0.3 to 3.0 parts by weight.

<Other dye (X)>
The base material (i) may further contain other dye (X) that does not correspond to the compound (S) and the compound (A).
Other dyes (X) are not particularly limited as long as the absorption maximum wavelength is less than 600 nm or more than 850 nm. For example, squarylium compounds, phthalocyanine compounds, cyanine compounds, naphthalocyanine compounds, croconium compounds And at least one compound selected from the group consisting of a porphyrin compound and a metal dithiolate compound. Depending on the absorption characteristics of the compound (S) and the target near-infrared transmission wavelength, the long wavelength side of the near-infrared transmission band in addition to the visible range can be obtained by using the compound (S) in combination with other dyes (X). Also, the incident angle dependency can be reduced, and good infrared sensing performance can be achieved.

  The content of the other dye (X) is, for example, a base material made of a transparent resin substrate (ii) containing the other dye (X) or the other dye (X) as the base material (i). When using a base material in which a resin layer such as an overcoat layer made of a curable resin or the like is laminated on the transparent resin substrate (ii) to be contained, it is preferably 0.01 to 100 parts by weight of the transparent resin. To 1.5 parts by weight, more preferably 0.02 to 1.0 parts by weight, particularly preferably 0.03 to 0.7 parts by weight, and serves as a glass support or base as the substrate (i). When using a substrate in which a transparent resin layer such as an overcoat layer made of a curable resin or the like is laminated on a resin support, a transparent resin layer containing the other dye (X) Is preferably 0. 100 parts by weight of the resin forming To 4.0 parts by weight, more preferably 0.2 to 3.0 parts by weight, particularly preferably 0.3 to 2.0 parts by weight. When the content of the other dye (X) is within the above range, both good near-infrared absorption characteristics and high visible light transmittance can be achieved.

<Transparent resin>
The transparent resin substrate (ii) and the (transparent) resin layer laminated on the substrate (ii), the resin support or the glass support can be formed using a transparent resin.
As transparent resin used for the said base material (i), 1 type may be individual and 2 or more types may be sufficient.

The transparent resin is not particularly limited as long as it does not impair the effects of the present invention. For example, it ensures thermal stability and moldability to a film, and dielectrics are formed by high-temperature deposition performed at a deposition temperature of 100 ° C. or higher. In order to use as a base material which can form a body multilayer film, the resin whose glass transition temperature (Tg) becomes like this. Preferably it is 110-380 degreeC, More preferably, it is 110-370 degreeC, More preferably, it is 120-360 degreeC. It is particularly preferable that the glass transition temperature of the resin is 140 ° C. or higher because a film ((transparent) resin layer and transparent resin substrate (ii)) on which a dielectric multilayer film can be deposited at a higher temperature can be obtained.
Specifically, Tg can be measured by the method described in the Examples below.

  As the transparent resin, when a resin body having a thickness of 0.1 mm made of the resin is formed, the total light transmittance (JIS K7375) of the resin body is preferably 75% or more, more preferably 78% or more, Particularly preferably, a resin of 80% or more can be used. If a resin having a total light transmittance in such a range is used, the obtained base material (i) exhibits good transparency as an optical film.

When a solvent-soluble resin is used as the transparent resin, the polystyrene-reduced weight average molecular weight (Mw) measured by gel permeation chromatography (GPC) method of the transparent resin is usually 15,000 to 350,000, Preferably it is 30,000-250,000, and a number average molecular weight (Mn) is 10,000-150,000 normally, Preferably it is 20,000-100,000.
Specifically, Mw and Mn can be measured by the methods described in the following examples.

  Examples of transparent resins include cyclic (poly) olefin resins, aromatic polyether resins, polyimide resins, fluorene polycarbonate resins, fluorene polyester resins, polycarbonate resins, polyamide (aramid) resins, and polyarylate resins. Resins, polysulfone resins, polyethersulfone resins, polyparaphenylene resins, polyamideimide resins, polyethylene naphthalate (PEN) resins, fluorinated aromatic polymer resins, (modified) acrylic resins, epoxy resins Examples thereof include resins, allyl ester curable resins, silsesquioxane ultraviolet curable resins, acrylic ultraviolet curable resins, and vinyl ultraviolet curable resins.

[Cyclic (poly) olefin resin]
The cyclic (poly) olefin resin is 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 hydrogenating the resin are preferred.

In the formula (X ₀ ), R ^{x1 to} R ^x4 each independently represents an atom or group selected from the following (i ′) to (ix ′), and k ^x , ^mx and p ^x are each independently 0 Or represents a positive integer.
(I ′) a hydrogen atom (ii ′) a halogen atom (iii ′) a trialkylsilyl group (iv ′) having a linking group containing an oxygen atom, a sulfur atom, a nitrogen atom or a silicon atom,
A substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms (v ′) a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms (vi ′) polar group (excluding (iv ′))
(Vii ′) an alkylidene group formed by bonding R ^x1 and R ^x2 or R ^x3 and R ^x4 to each other (provided that R ^{x1 to} R ^x4 not involved in the bonding are independently the above (i ′ ) To (vi ′) represents an atom or group selected from.
(Viii ′) R ^x1 and R ^x2 or R ^x3 and R ^x4 are bonded to each other to form a monocyclic or polycyclic hydrocarbon ring or heterocyclic ring (provided that R ^{x1 to} R which are not involved in the bond) ^x4 each independently represents an atom or group selected from the above (i ′) to (vi ′).
(Ix ′) A monocyclic hydrocarbon ring or heterocycle formed by bonding R ^x2 and R ^x3 to each other (provided that R ^x1 and R ^x4 not involved in the bonding are independently the above (i Represents an atom or group selected from ') to (vi').

In formula (Y ₀ ), R ^y1 and R ^y2 each independently represents an atom or group selected from the above (i ′) to (vi ′), or R ^y1 and R ^y2 are bonded to each other. formed monocyclic or polycyclic alicyclic hydrocarbon, an aromatic hydrocarbon or heterocyclic, k ^y and p ^y are each independently, represent 0 or a positive integer.

[Aromatic polyether resin]
The aromatic polyether-based resin preferably has 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 > -R < ⁴ > represents a C1-C12 monovalent organic group each independently, and ad represents the integer of 0-4 each independently.

In the formula (2), each R ¹ to R ⁴ and a~d are independently the same meaning as R ¹ to R ⁴ and a~d of the formula (1), Y represents a single bond, -SO ₂ -Or> C = O, 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, and g and h each independently represent 0 to 4 And m represents 0 or 1. However, when m is 0, R ⁷ is not a cyano group.

  The aromatic polyether resin further 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). Is preferred.

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

In formula (4), R ⁷ , R ⁸ , Y, m, g and h are each independently synonymous with R ⁷ , R ⁸ , Y, m, g and h in formula (2), and R ⁵ , R ⁶ , Z, n, e and f are each independently synonymous with R ⁵ , R ⁶ , Z, n, e and f in the formula (3).

[Polyimide resin]
The polyimide resin is not particularly limited as long as it is a high molecular compound containing an imide bond in a repeating unit. For example, the method described in JP-A-2006-199945 and JP-A-2008-163107 is used. Can be synthesized.

[Fluorene polycarbonate resin]
The fluorene polycarbonate resin is not particularly limited as long as it is a polycarbonate resin containing a fluorene moiety, and is described in, for example, JP-A-2008-163194>

[Fluorene polyester resin]
The fluorene polyester resin is not particularly limited as long as it is a polyester resin containing a fluorene moiety. For example, the fluorene polyester resin is synthesized by a method described in JP 2010-285505 A or JP 2011-197450 A. Can do.

[Fluorinated aromatic polymer resin]
The fluorinated aromatic polymer resin is not particularly limited, but is selected from the group consisting of an aromatic ring having at least one fluorine atom, an ether bond, a ketone bond, a sulfone bond, an amide bond, an imide bond, and an ester bond. The polymer preferably contains a repeating unit containing at least one bond, and can be synthesized, for example, by the method described in JP-A-2008-181121.

[Acrylic UV curable resin]
The acrylic ultraviolet curable resin is not particularly limited, but is synthesized from a resin composition containing a compound having one or more acrylic or methacrylic groups in the molecule and a compound that decomposes by ultraviolet rays to generate active radicals. Can be mentioned. The acrylic ultraviolet curable resin is a base material in which a transparent resin layer containing a compound (S) and a curable resin is laminated on a glass support or a base resin support as the base (i) In the case of using a substrate in which a resin layer such as an overcoat layer made of a curable resin or the like is laminated on the transparent resin substrate (ii) containing the compound (S), it is particularly preferably used as the curable resin. be able to.

[Commercial goods]
The following commercial products etc. can be mentioned as a commercial item of transparent resin. Examples of commercially available cyclic (poly) olefin-based resins include Arton manufactured by JSR Co., Ltd., ZEONOR manufactured by Nippon Zeon Co., Ltd., APEL manufactured by Mitsui Chemicals, Inc., 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 Neoprim L manufactured by Mitsubishi Gas Chemical Co., Ltd. Examples of commercially available polycarbonate resins include Pure Ace manufactured by Teijin Limited. Examples of commercially available fluorene polycarbonate resins include Iupizeta EP-5000 manufactured by Mitsubishi Gas Chemical Co., Ltd. Examples of commercially available fluorene polyester resins include OKP4HT manufactured by Osaka Gas Chemical Co., Ltd. Examples of commercially available acrylic resins include NIPPON CATALYST ACRYVIEWER. Examples of commercially available silsesquioxane-based ultraviolet curable resins include Silplus manufactured by Nippon Steel Chemical Co., Ltd.

<Other ingredients>
The base material (i) may further contain other components such as an antioxidant, a near-ultraviolet absorber, a fluorescence quencher, and a metal complex compound as long as the effects of the present invention are not impaired. Moreover, when manufacturing base material (i) by the cast molding mentioned later, manufacture of base material (i) can be made easy by adding a leveling agent and an antifoamer. These other components may be used alone or in combination of two or more.

  Examples of the near ultraviolet absorber include azomethine compounds, indole compounds, benzotriazole compounds, and triazine compounds.

  Examples of the antioxidant include 2,6-di-t-butyl-4-methylphenol, 2,2′-dioxy-3,3′-di-t-butyl-5,5′-dimethyldiphenylmethane, and Tetrakis [methylene-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] methane.

  These other components may be mixed with the resin or the like when producing the substrate (i), or may be added when the resin is synthesized. The addition amount is appropriately selected according to the desired properties, but is usually 0.01 to 5.0 parts by weight, preferably 0.05 to 2.0 parts by weight, based on 100 parts by weight of the resin. .

<Manufacturing method of substrate (i)>
When the base material (i) is a base material including a transparent resin substrate (ii) containing the compound (S), the transparent resin substrate (ii) is formed by, for example, melt molding or cast molding. be able to.

  The substrate (i) contains a resin layer such as an overcoat layer made of a curable resin or the compound (S) on a glass support or a resin support or a transparent resin substrate (ii) serving as a base. In the case of a base material on which a transparent resin layer such as an overcoat layer made of a curable resin is laminated, for example, on a glass support, a base resin support or a transparent resin substrate (ii), if necessary By melt-molding or cast-molding a resin solution containing the compound (S), the solvent is preferably removed by drying after coating by a method such as spin coating, slit coating, or inkjet, and if necessary, further light irradiation or By heating, a base material having a (transparent) resin layer formed on a glass support or a resin support or a transparent resin substrate (ii) as a base can be produced.

[Melting]
Specifically, the melt molding is a method of melt-molding pellets obtained by melt-kneading a resin and optionally a compound (S) or the like; a resin containing a resin and optionally a compound (S) Examples thereof include a method of melt-molding the composition; or a method of melt-molding pellets obtained by removing the solvent from the resin composition containing the resin and the solvent and, if necessary, the compound (S). Examples of the melt molding method include injection molding, melt extrusion molding, and blow molding.

[Cast molding]
As the cast molding, a resin composition containing a resin and a solvent and, if necessary, a compound (S) is cast on a suitable support to remove the solvent; or a photocurable resin and / or heat After removing the solvent by casting a curable composition containing a curable resin and, if necessary, the compound (S) on an appropriate support, and curing by an appropriate method such as ultraviolet irradiation or heating. It can also be manufactured.
When the base material (i) is a base material made of a transparent resin substrate (ii) containing the compound (S), the base material (i) is coated with a coating film from the support after cast molding. The substrate (i) can be obtained by peeling, and a (transparent) resin layer is formed on a support such as a glass support or a resin support serving as a base or a transparent resin substrate (ii). In the case of a laminated base material, the base material (i) can be obtained by not peeling the coating film after cast molding.

  As said support body, the support body made from a glass plate, a steel belt, a steel drum, and transparent resin (for example, a polyester film, a cyclic olefin resin film) is mentioned, for example.

  Further, the optical component such as glass plate, quartz or transparent plastic is coated with the resin composition and the solvent is dried, or the curable composition is coated and cured and dried. A transparent resin layer can also be formed on the component.

  The amount of residual solvent in the (transparent) resin layer and the transparent resin substrate (ii) obtained by the above method should be as small as possible. Specifically, the amount of the residual solvent is preferably 3% by weight or less, more preferably 1% by weight or less, based on 100% by weight of the (transparent) resin layer or the transparent resin substrate (ii). Preferably it is 0.5 weight% or less. When the amount of residual solvent is in the above range, a (transparent) resin layer and a transparent resin substrate (ii) that can easily exhibit a desired function, in which deformation and characteristics are hardly changed, are obtained.

[Dielectric multilayer film]
The dielectric multilayer film is preferably a film having a capability of cutting unnecessary near infrared rays by reflection and transmitting necessary near infrared rays. In the present invention, the dielectric multilayer film may be provided on one side of the substrate (i) or on both sides. When it is provided on one side, it is excellent in production cost and manufacturability, and when it is provided on both sides, an optical filter having high strength and less warpage can be obtained.

  When the optical filter of the present invention is applied to applications such as a solid-state image sensor, it is preferable that the warp of the optical filter is small. Therefore, the dielectric multilayer film is preferably provided on both surfaces of the substrate (i), and is provided on both surfaces. The dielectric multilayer films may have the same or different spectral characteristics. In the case where the spectral characteristics of the dielectric multilayer films provided on both surfaces are the same, the transmittance of the light blocking zones Za and Zc can be efficiently reduced in the near-infrared region, and the spectral characteristics of the dielectric multilayer films provided on both surfaces can be reduced. In the case of being different, it tends to be easy to widen the light blocking band Zc to the longer wavelength side.

  Examples of the dielectric multilayer film include those in which high refractive index material layers and low refractive index material layers are alternately stacked. As a material constituting the high refractive index material layer, a material having a refractive index of 1.7 or more can be used, and a material having a refractive index of usually 1.7 to 2.5 is selected. Examples of such materials include titanium oxide, zirconium oxide, tantalum pentoxide, niobium pentoxide, lanthanum oxide, yttrium oxide, zinc oxide, zinc sulfide, or indium oxide as the main components, and titanium oxide, tin oxide, and / or Or what contains a small amount (for example, 0-10 weight% with respect to a main component) of cerium oxide etc. is mentioned.

  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 usually 1.2 to 1.6 is selected. Examples of such materials include silica, alumina, lanthanum fluoride, magnesium fluoride, and sodium hexafluoride sodium.

  The method of laminating the high refractive index material layer and the low refractive index material layer is not particularly limited as long as a dielectric multilayer film in which these material layers are laminated is formed. For example, a high-refractive index material layer and a low-refractive index material layer are formed directly on the substrate (i) by performing a CVD method, a sputtering method, a vacuum deposition method, an ion-assisted deposition method, an ion plating method, or the like. Alternating dielectric multilayer films can be formed.

  The physical film thickness of each of the high-refractive index material layer and the low-refractive index material layer is preferably 5 to 500 nm, although it depends on the refractive index of each layer, and is the total physical film thickness of the dielectric multilayer film. The value is preferably 1.0 to 8.0 μm for the entire optical filter.

  The total number of stacked high refractive index material layers and low refractive index material layers in the dielectric multilayer film is preferably 16 to 70 layers, and more preferably 20 to 60 layers as a whole. If the thickness of each layer, the thickness of the dielectric multilayer film as a whole of the optical filter, and the total number of layers are within the above ranges, a sufficient manufacturing margin can be secured, and the warpage of the optical filter and cracks in the dielectric multilayer film can be reduced. can do.

  In the present invention, the material type 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 stacking, and the number of stacks are appropriately selected. Thus, it is possible to obtain an optical filter having a light blocking band and a light transmission band of a desired wavelength in the near infrared wavelength range while ensuring a sufficient transmittance in the visible range.

  Here, in order to optimize the above conditions, for example, optical thin film design software (for example, Essential Macleod, manufactured by Thin Film Center) is used, and the transmittance in the wavelength range where light transmission is desired to be suppressed in the near-infrared wavelength range. The parameter may be set so as to increase the transmittance in the wavelength region where light is to be transmitted. For example, in the case where a light transmission band is provided in the vicinity of 850 nm by the dielectric multilayer film formed on both surfaces, the above-described software is used, and the target transmittance of one dielectric multilayer film at a wavelength of 770 to 810 nm is 0%, 830 to 870 nm. And the target transmittance of each wavelength region is set to 0.5 or less, the target transmittance of the other dielectric multilayer film at a wavelength of 830 to 870 nm is set to 100%, There is a parameter setting method in which the target transmittance of 900 to 1150 nm is set to 0% and the value of Target Tolerance in each wavelength region is 0.5 or less.

[Other functional membranes]
As long as the optical filter of the present invention does not impair the effects of the present invention, the optical filter is provided between the base material (i) and the dielectric multilayer film, on the side opposite to the surface on which the dielectric multilayer film is provided. On the surface or the surface opposite to the surface on which the substrate (i) of the dielectric multilayer film is provided, the surface hardness of the substrate (i) or the dielectric multilayer film is improved, the chemical resistance is improved, the antistatic A functional film such as an antireflection film, a hard coat film, or an antistatic film can be appropriately provided for the purpose of scratch removal.

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

The method for laminating the functional film is not particularly limited, but a coating agent such as an antireflection agent, a hard coating agent and / or an antistatic agent is melted in the base material (i) or the dielectric multilayer film as described above. Examples of the method include molding or cast molding.
Further, the composition can also be produced by applying a curable composition containing the coating agent or the like on the substrate (i) or the dielectric multilayer film with a bar coater or the like and then curing the composition by ultraviolet irradiation or the like.

  Examples of the coating agent include ultraviolet (UV) / electron beam (EB) curable resins and thermosetting resins. Specifically, vinyl compounds, urethanes, urethane acrylates, acrylates, epoxy And epoxy acrylate resins. Examples of the curable composition containing these coating agents include vinyl, urethane, urethane acrylate, acrylate, epoxy, and epoxy acrylate curable compositions.

  Moreover, the said curable composition may contain the polymerization initiator. As the polymerization initiator, a known photopolymerization initiator or a thermal polymerization initiator can be used, and a photopolymerization initiator and a thermal polymerization initiator may be used in combination. A polymerization initiator may be used individually by 1 type, and may use 2 or more types.

  In the curable composition, the blending ratio of the polymerization initiator is preferably 0.1 to 10% by weight, more preferably 0.5 to 10% by weight, when the total amount of the curable composition is 100% by weight. More preferably, it is 1 to 5% by weight. When the blending ratio of the polymerization initiator is within the above range, it is possible to obtain a functional film such as an antireflective film, a hard coat film or an antistatic film having excellent curing characteristics and handleability of the curable composition and having a desired hardness. it can.

Furthermore, an organic solvent may be added as a solvent to the curable composition, and known organic solvents can be used. Specific examples of organic solvents include alcohols such as methanol, ethanol, isopropanol, butanol and octanol; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; ethyl acetate, butyl acetate, ethyl lactate, γ-butyrolactone, propylene Esters such as 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; Dimethylformamide, dimethylacetamide, N- Examples include amides such as methylpyrrolidone.
These solvents may be used alone or in combination of two or more.

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

  Further, for the purpose of improving the adhesion between the base material (i) and the functional film and / or the dielectric multilayer film, and the adhesion between the functional film and the dielectric multilayer film, the base material (i), the functional film or the dielectric Surface treatment such as corona treatment or plasma treatment may be applied to the surface of the multilayer film.

[Use of optical filter]
The optical filter of the present invention has a wide viewing angle and can selectively transmit visible light and some near infrared rays. Therefore, it is useful for correcting the visibility of a solid-state imaging device such as a CCD or CMOS image sensor having both a camera function and a near-infrared sensing function. In particular, devices including camera modules such as digital still cameras, smartphone cameras, mobile phone cameras, digital video cameras, wearable device cameras, PC cameras, surveillance cameras, automotive cameras, night vision cameras, motion capture, laser distance It is useful for measuring devices, virtual try-on, license plate recognition devices, televisions, car navigation systems, portable information terminals, video game machines, portable game machines, fingerprint authentication systems, digital music players, and the like.

[Solid-state imaging device]
The solid-state imaging device of the present invention includes the optical filter of the present invention. Here, the solid-state imaging device is an image sensor including a solid-state imaging device such as a CCD or a CMOS image sensor having both a camera function and a near-infrared sensing function. Specifically, a digital still camera, a smartphone camera, a mobile phone The present invention can be used in applications such as devices including camera modules such as telephone cameras, wearable device cameras, and digital video cameras. For example, the camera module of the present invention includes the optical filter of the present invention, and further includes, for example, a lens unit and a sensor unit.

  EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example, this invention is not limited to these Examples at all. “Parts” means “parts by weight” unless otherwise specified. Moreover, the measurement method of each physical property value and the evaluation method of the physical property are as follows.

<Molecular weight>
The molecular weight of the resin obtained in the resin synthesis example was measured by the following method (a) or (b) in consideration of the solubility of each resin in a solvent.

  (A) Weight of standard polystyrene conversion using a gel permeation chromatography (GPC) apparatus (150C type, column: Tosoh Co., Ltd. H type column, developing solvent: o-dichlorobenzene) manufactured by WATERS Average molecular weight (Mw) and number average molecular weight (Mn) were measured.

  (B) Using a GPC apparatus (HLC-8220 type, column: TSKgelα-M, developing solvent: tetrahydrofuran) manufactured by Tosoh Corporation, the weight average molecular weight (Mw) and number average molecular weight (Mn) in terms of standard polystyrene are measured. did.

In addition, about the resin synthesize | combined in the resin synthesis example 3 mentioned later, the logarithmic viscosity was measured by the following method (c) instead of the molecular weight measurement by the said method.
(C) A part of the polyimide resin solution was put into anhydrous methanol to precipitate a polyimide resin, and filtered to separate unreacted monomers. 0.1 g of polyimide obtained by vacuum drying at 80 ° C. for 12 hours was dissolved in 20 mL of N-methyl-2-pyrrolidone, and the obtained diluted polymer solution was used for 30 using a Canon-Fenske viscometer. The logarithmic viscosity (μ) at ° C. was determined by the following formula.
_{μ = {ln (t s /} t 0)} / C
t ₀ : Flowing time of solvent t _s : Flowing time of dilute polymer solution C: 0.5 g / dL

<Glass transition temperature (Tg)>
The Tg of the resin obtained in the resin synthesis example was measured using a differential scanning calorimeter (DSC6200) manufactured by SII Nano Technologies, Inc. at a rate of temperature increase of 20 ° C. per minute under a nitrogen stream.

<Spectral transmittance>
(Ta), (Xc), (Tb) and (Xf) of the substrate, and transmittance in each wavelength region of the optical filter, (Xa), (Xb), (Xd), (Xe) and (Xa ′) ) Was measured using a spectrophotometer (U-4100) manufactured by Hitachi High-Technologies Corporation. The optical properties of the substrates used in the comparative examples were measured in the same manner as (Ta), (Xc), (Tb) or (Xf).

  Here, with respect to the transmittance when measured from the vertical direction of the optical filter, light transmitted perpendicularly to the filter was measured as shown in FIG. Further, the transmittance when measured from an angle of 30 ° with respect to the vertical direction of the optical filter was obtained by measuring light transmitted at an angle of 30 ° with respect to the vertical direction of the filter as shown in FIG.

[Synthesis example]
Compound (S) and compound (A) used in the following examples can be synthesized by a generally known method. For example, Japanese Patent No. 3094037, Japanese Patent No. 3703869, -228448, JP-A 1-146846, JP-A 1-228960, Japanese Patent No. 4081149, JP-A 63-124054, “Phthalocyanine -Chemistry and Function” (IPC, 1997) ), Synthesis with reference to the methods described in JP 2007-169315 A, JP 2009-108267 A, JP 2010-241873 A, JP 3699464 A, JP 4740631 A, and the like. be able to.

<Resin synthesis example 1>
8-methyl-8-methoxycarbonyltetracyclo represented by the following formula (a) [4.4.0.1 ^2,5 . 1 ^7,10 ] 100 parts of dodec-3-ene, 18 parts of 1-hexene (molecular weight regulator) and 300 parts of toluene (solvent for ring-opening polymerization reaction) were charged into a nitrogen-substituted reaction vessel, and the resulting solution was charged. Heated to 80 ° C. Next, 0.2 parts of a toluene solution of triethylaluminum (concentration 0.6 mol / liter) and a toluene solution of methanol-modified tungsten hexachloride (concentration 0.025 mol / liter) 0 as a polymerization catalyst were added to the solution in the reaction vessel. 9 parts was added, and ring-opening polymerization was performed by heating and stirring at 80 ° C. for 3 hours to obtain a ring-opening polymer solution. The polymerization conversion in this polymerization was 97%.

1,000 parts of the ring-opening polymer solution thus obtained was charged into an autoclave, and 0.12 part of RuHCl (CO) [P (C ₆ H ₅ ) ₃ ] ₃ was added to the ring-opening polymer solution. Then, the hydrogenation reaction was performed by heating and stirring for 3 hours under the conditions of a hydrogen gas pressure of 100 kg / cm ² and a reaction temperature of 165 ° C. After cooling the obtained reaction solution (hydrogenated polymer solution), the hydrogen gas was released. This reaction solution was poured into a large amount of methanol to separate and recover the coagulated product, and 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 weight average molecular weight (Mw) of 137,000, and a glass transition temperature (Tg) of 165 ° C.

<Resin synthesis example 2>
In a 3 L four-necked flask, 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 of potassium carbonate ( 0.300 mol), 443 g of N, N-dimethylacetamide (hereinafter also referred to as “DMAc”) and 111 g of toluene were added. Subsequently, a thermometer, a stirrer, a three-way cock with a nitrogen introduction tube, a Dean Stark tube and a cooling tube were attached to the four-necked flask. Next, after the atmosphere in the flask was replaced with nitrogen, the resulting solution was reacted at 140 ° C. for 3 hours, and water produced was removed from the Dean-Stark tube as needed. When no more water was observed, the temperature was gradually raised to 160 ° C. and reacted at that temperature for 6 hours. After cooling to room temperature (25 ° C.), the produced salt was removed with a filter paper, the filtrate was poured into methanol for reprecipitation, 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 weight average molecular weight (Mw) of 188,000, and a glass transition temperature (Tg) of 285 ° C.

<Resin synthesis example 3>
To a 500 mL five-necked flask equipped with a thermometer, a stirrer, a nitrogen introducing tube, a dropping funnel with a side tube, a Dean-Stark tube and a condenser tube, was added 1,4-bis (4-amino-α, α under a nitrogen stream. -Dimethylbenzyl) benzene (27.66 g, 0.08 mol) and 4,4'-bis (4-aminophenoxy) biphenyl (7.38 g, 0.02 mol) were added, and γ-butyrolactone (68.65 g) and DMAc 17. Dissolved in 16 g. The resulting solution was cooled to 5 ° C. using an ice-water bath, and while maintaining the same temperature, 22.62 g (0.1 mol) of 1,2,4,5-cyclohexanetetracarboxylic dianhydride and an imidization catalyst As a result, 0.50 g (0.005 mol) of triethylamine was added all at once. After completion of the addition, the temperature was raised to 180 ° C. and refluxed for 6 hours while distilling off the distillate as needed. After refluxing for 6 hours, it was air-cooled until the internal temperature reached 100 ° C., diluted by adding 143.6 g of DMAc, and cooled with stirring to obtain 264.16 g of a polyimide resin solution having a solid content concentration of 20% by weight. . A part of this polyimide resin solution was poured into 1 L of methanol to precipitate the polyimide. The polyimide separated by filtration was washed with methanol and dried in a vacuum dryer at 100 ° C. for 24 hours to obtain a white powder (hereinafter also referred to as “resin C”).

The IR spectrum of the obtained resin C was measured, 1704 cm ^-1 characteristic of imido group, absorption of 1770 cm ^-1 were observed. Resin C had a glass transition temperature (Tg) of 310 ° C. and a logarithmic viscosity of 0.87.

[Example 1]
In Example 1, an optical filter having a base material made of a transparent resin substrate was prepared according to the following procedure and conditions.
In a container, 100 parts of resin A obtained in Resin Synthesis Example 1, 0.03 part of compound (s-5) described in Table 1 (maximum absorption wavelength 770 nm in dichloromethane) as compound (S), and methylene chloride Was added to prepare a solution having a resin concentration of 20% by weight. The obtained solution was cast on a smooth glass plate, dried at 20 ° C. for 8 hours, and then peeled off from the glass plate. The peeled coating film was further dried at 100 ° C. under reduced pressure for 8 hours to obtain a base material composed of 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 the substrate was measured, and (Ta), (Tb), (Xc), and (Xf) were obtained. The results are shown in FIG.

Subsequently, the dielectric multilayer film (I) is formed on one surface of the obtained base material, and the dielectric multilayer film (II) is further formed on the other surface of the base material, so that the optical thickness is about 0.104 mm. A filter was obtained.
The dielectric multilayer film (I) is formed by alternately laminating silica (SiO ₂ ) layers and titania (TiO ₂ ) layers at a deposition temperature of 100 ° C. (a total of 24 layers). The dielectric multilayer film (II) is formed by alternately laminating silica (SiO ₂ ) layers and titania (TiO ₂ ) layers at a deposition temperature of 100 ° C. (18 layers in total). In both of the dielectric multilayer films (I) and (II), the silica layer and the titania layer are in order of the titania layer, the silica layer, the titania layer,..., The silica layer, the titania layer, and the silica layer from the substrate side. The outermost layer of the optical filter was a silica layer.

The dielectric multilayer films (I) and (II) were designed as follows.
Regarding the thickness and number of layers, the wavelength dependence of the refractive index of the base material and the absorption characteristics of the compound (S) used to achieve the antireflection effect in the visible range and the selective transmission / reflection performance in the near infrared range. Was optimized using optical thin film design software (Essential Macleod, manufactured by Thin Film Center). When performing optimization, in this example, the input parameters (Target values) to the software are as shown in Table 2 below.

  As a result of the optimization of the film configuration, in Example 1, the dielectric multilayer film (I) is formed by alternately laminating a silica layer having a thickness of about 13 to 174 nm and a titania layer having a thickness of about 9 to 200 nm. The dielectric multi-layer film (II) is a multi-layered film having 18 layers, in which a silica layer having a film thickness of about 41 to 198 nm and a titania layer having a film thickness of about 12 to 122 nm are alternately stacked. It became a deposited film. Table 3 shows an example of the optimized film configuration.

  The obtained optical filter was measured in the vertical direction and the spectral transmittance measured from an angle of 30 ° with respect to the vertical direction, and the optical characteristics in each wavelength region were evaluated. The results are shown in FIG.

[Example 2]
In Example 1, 0.03 part of compound (s-11) (absorption maximum wavelength 776 nm in dichloromethane) described in Table 1 was used instead of 0.03 part of compound (s-5), and As compound (A), 0.03 part of compound (a-1) represented by the following formula (a-1) (absorption maximum wavelength in dichloromethane of 698 nm) and represented by the following formula (a-2) Transparent resin containing compound (S) and compound (A) under the same procedure and conditions as in Example 1 except that 0.03 part of compound (a-2) (absorption maximum wavelength in dichloromethane: 733 nm) was used. A base material made of a substrate was obtained. The spectral transmittance of the substrate was measured, and (Ta), (Tb), (Xc), and (Xf) were obtained. The results are shown in FIG.

Subsequently, in the same manner as in Example 1, a silica (SiO ₂ ) layer and a titania (TiO ₂ ) layer are alternately laminated on one side of the obtained substrate (24 layers in total). And a dielectric multilayer film (IV) in which a silica (SiO ₂ ) layer and a titania (TiO ₂ ) layer are alternately laminated on the other surface of the substrate (18 layers in total). An optical filter having a thickness of about 0.104 mm was obtained. The dielectric multilayer film was designed using design parameters as shown in Table 4 below in consideration of the wavelength dependence of the refractive index of the substrate.

  As a result of the optimization of the film configuration, in Example 2, the dielectric multilayer film (III) is formed by alternately laminating a silica layer having a thickness of about 27 to 198 nm and a titania layer having a thickness of about 10 to 121 nm. The dielectric multi-layer film (IV) is a multi-layered film having 18 layers, in which a silica layer having a thickness of about 41 to 198 nm and a titania layer having a thickness of about 12 to 122 nm are alternately stacked. It became a deposited film. Table 5 shows an example of the optimized film configuration.

  The spectral transmittance of the obtained optical filter was measured, and the optical characteristics in each wavelength region were evaluated. The results are shown in FIG.

[Example 3]
In Example 3, an optical filter having a base material composed of a transparent resin substrate having a resin layer on both sides was prepared according to the following procedure and conditions.
In Example 1, 0.03 part of the compound (s-23) shown in Table 1 (maximum absorption wavelength 784 nm in dichloromethane) was used instead of 0.03 part of the compound (s-5). A transparent resin substrate containing the compound (S) was obtained by the same procedure and conditions as in Example 1.

A resin composition (1) having the following composition was applied to one side of the obtained transparent resin substrate 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 coating conditions of the bar coater were adjusted so that the thickness after drying was 2 μm. Next, it exposed using the conveyor type exposure machine (exposure amount 500mJ / cm < ² >, 200mW), the resin composition (1) was hardened, and the resin layer was formed on the substrate made from transparent resin. Similarly, a resin layer is formed on the other surface of the transparent resin substrate using the resin composition (1), and a base material having a resin layer on both surfaces of the transparent resin substrate containing the compound (S) is obtained. It was. The spectral transmittance of the substrate was measured, and (Ta), (Tb), (Xc), and (Xf) were obtained. The results are shown in Table 7.

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

Subsequently, in the same manner as in Example 1, a silica (SiO ₂ ) layer and a titania (TiO ₂ ) layer are alternately laminated on one side of the obtained base material (24 layers in total). And a dielectric multilayer film (VI) in which a silica (SiO ₂ ) layer and a titania (TiO ₂ ) layer are alternately laminated on the other surface of the substrate (18 layers in total). An optical filter having a thickness of about 0.108 mm was obtained. The dielectric multilayer film was designed using the same design parameters as in Example 1 in consideration of the wavelength dependence of the refractive index of the substrate as in Example 1. The spectral transmittance of this optical filter was measured, and the optical characteristics in each wavelength region were evaluated. The results are shown in Table 7.

[Example 4]
In Example 3, in place of 0.03 part of compound (s-23), 0.01 part of compound (s-5) described in Table 1 and compound (s-21) described in Table 1 (in dichloromethane) The base material which has a resin layer on both surfaces of the transparent resin board | substrate containing a compound (S) in the same procedure and conditions as Example 3 except having used 0.02 part of absorption maximum wavelength in 782 nm. . The spectral transmittance of the substrate was measured, and (Ta), (Tb), (Xc), and (Xf) were obtained. The results are shown in Table 7.

Subsequently, in the same manner as in Example 1, a silica (SiO ₂ ) layer and a titania (TiO ₂ ) layer are alternately laminated on one side of the obtained base material (24 layers in total). And a dielectric multilayer film (VIII) formed by alternately laminating silica (SiO ₂ ) layers and titania (TiO ₂ ) layers (18 layers in total) on the other surface of the substrate. An optical filter having a thickness of about 0.108 mm was obtained. The dielectric multilayer film was designed using the same design parameters as in Example 1 in consideration of the wavelength dependence of the refractive index of the substrate as in Example 1. The spectral transmittance of this optical filter was measured, and the optical characteristics in each wavelength region were evaluated. The results are shown in Table 7.

[Example 5]
In Example 3, 0.04 part of the compound (s-11) described in Table 1 was used instead of 0.03 part of the compound (s-23), and the following formula was used as the compound (A). 0.02 part of compound (a-3) represented by (a-3) (maximum absorption wavelength 703 nm in dichloromethane) and compound (a-4) represented by the following formula (a-4) (in dichloromethane) The base material which has a resin layer on both surfaces of the transparent resin board | substrate containing a compound (S) on the same procedure and conditions as Example 3 except having used 0.06 part of absorption maximum wavelength in 736 nm) was obtained. . The spectral transmittance of the substrate was measured, and (Ta), (Tb), (Xc), and (Xf) were obtained. The results are shown in Table 7.

Subsequently, in the same manner as in Example 1, a silica (SiO ₂ ) layer and a titania (TiO ₂ ) layer are alternately laminated on one side of the obtained base material (24 layers in total). And a dielectric multilayer film (X) in which a silica (SiO ₂ ) layer and a titania (TiO ₂ ) layer are alternately laminated on the other surface of the substrate (18 layers in total). An optical filter having a thickness of about 0.108 mm was obtained. The dielectric multilayer film was designed using the same design parameters as in Example 2 in consideration of the wavelength dependence of the refractive index of the substrate as in Example 1. The spectral transmittance of this optical filter was measured, and the optical characteristics in each wavelength region were evaluated. The results are shown in Table 7.

[Example 6]
In Example 6, an optical filter having a base material composed of a resin substrate having a transparent resin layer containing the compound (S) on both surfaces was prepared according to the following procedure and conditions.
Resin A and methylene chloride obtained in Resin Synthesis Example 1 were added to a container to prepare a solution having a resin concentration of 20% by weight, and the resin was used in the same manner as in Example 1 except that the obtained solution was used. A substrate was made.

  A transparent resin layer was formed on both sides of the obtained resin substrate in the same manner as in Example 3 except that the resin composition (2) having the following composition was used instead of the resin composition (1). The base material which consists of a resin-made board | substrate which has a transparent resin layer containing (S) was obtained. The spectral transmittance of the substrate was measured, and (Ta), (Tb), (Xc), and (Xf) were obtained. The results are shown in Table 7.

  Resin composition (2) (TSC: 25%): 100 parts by weight of tricyclodecane dimethanol acrylate, 4 parts by weight of 1-hydroxycyclohexyl phenyl ketone, 0.75 part by weight of compound (s-5), compound (a-2) 0.75 part by weight, compound (a-3) 0.75 part by weight, methyl ethyl ketone (solvent)

Subsequently, in the same manner as in Example 1, a silica (SiO ₂ ) layer and a titania (TiO ₂ ) layer are alternately laminated on one side of the obtained base material (24 layers in total). And a dielectric multilayer film (XII) in which silica (SiO ₂ ) layers and titania (TiO ₂ ) layers are alternately laminated (18 layers in total) on the other surface of the substrate. An optical filter having a thickness of about 0.110 mm was obtained. The dielectric multilayer film was designed using the same design parameters as in Example 2 in consideration of the wavelength dependence of the refractive index of the substrate as in Example 1. The spectral transmittance of this optical filter was measured, and the optical characteristics in each wavelength region were evaluated. The results are shown in Table 7.

[Example 7]
In Example 7, an optical filter having a base material composed of a transparent glass substrate having a transparent resin layer containing the compound (S) on one side was prepared by the following procedure and conditions.
On a transparent glass substrate “OA-10G (thickness 200 μm)” (manufactured by Nippon Electric Glass Co., Ltd.) cut to a size of 60 mm in length and 60 mm in width, a resin composition (3) having the following composition was applied by a spin coater. A coating film was formed by heating on a hot plate at 80 ° C. for 2 minutes to volatilize and remove the solvent. Under the present circumstances, the application | coating conditions of the spin coater were adjusted so that the thickness after drying might be set to 2 micrometers. Next, exposure (exposure amount: 500 mJ / cm ² , 200 mW) is carried out using a conveyor type exposure machine, the coating film is cured, and a substrate made of a transparent glass substrate having a transparent resin layer containing the compound (S) is prepared. Obtained. The spectral transmittance of the substrate was measured, and (Ta), (Tb), (Xc), and (Xf) were obtained. The results are shown in Table 7.

  Resin composition (3) (TSC: 35%): 20 parts by weight of tricyclodecane dimethanol acrylate, 80 parts by weight of dipentaerythritol hexaacrylate, 4 parts by weight of 1-hydroxycyclohexyl phenyl ketone, compound (s-5) 5 parts by weight, compound (a-2) 1.5 parts by weight, compound (a-3) 1.5 parts by weight, methyl ethyl ketone (solvent)

Subsequently, similarly to Example 1, a dielectric multilayer film (XIII) in which a silica (SiO ₂ ) layer and a titania (TiO ₂ ) layer are alternately laminated on one side of the obtained base material (24 layers in total). And a dielectric multilayer film (XIV) in which a silica (SiO ₂ ) layer and a titania (TiO ₂ ) layer are alternately laminated on the other surface of the substrate (18 layers in total). An optical filter having a thickness of about 0.210 mm was obtained. The dielectric multilayer film was designed using the same design parameters as in Example 2 in consideration of the wavelength dependence of the refractive index of the substrate as in Example 1. The spectral transmittance of this optical filter was measured, and the optical characteristics in each wavelength region were evaluated. The results are shown in Table 7.

[Comparative Example 1]
In Example 1, a substrate was prepared in the same manner as in Example 1 except that the compound (S) was not used. Subsequently, as in Example 1, a dielectric multilayer film (XV) in which a silica (SiO ₂ ) layer and a titania (TiO ₂ ) layer are alternately laminated on one side of the obtained base material (24 layers in total). And a dielectric multilayer film (XVI) in which a silica (SiO ₂ ) layer and a titania (TiO ₂ ) layer are alternately laminated on the other surface of the substrate (18 layers in total). An optical filter having a thickness of about 0.106 mm was obtained. The dielectric multilayer film was designed using the same design parameters as in Example 1 in consideration of the wavelength dependence of the refractive index of the substrate. The spectral transmittance of this optical filter was measured, and the optical characteristics in each wavelength region were evaluated. The results are shown in FIG.

[Comparative Example 2]
As in Example 1, except that a near-infrared absorbing glass substrate “BS-6 (thickness 210 μm)” (manufactured by Matsunami Glass Industry Co., Ltd.) cut to a size of 60 mm in length and 60 mm in width was used as the base material. Thus, a dielectric multilayer film (XVII) formed by alternately laminating silica (SiO ₂ ) layers and titania (TiO ₂ ) layers on one side of the base material (total 24 layers) is formed. An optical filter having a thickness of about 0.216 mm is formed on one surface by forming a dielectric multilayer film (XVIII) in which silica (SiO ₂ ) layers and titania (TiO ₂ ) layers are alternately laminated (18 layers in total). Got. The dielectric multilayer film was designed using design parameters as shown in Table 6 below, taking into account the wavelength dependence of the refractive index of the substrate. The spectral transmittance of this optical filter was measured, and the optical characteristics in each wavelength region were evaluated. The results are shown in FIG.

[Comparative Example 3]
In Example 1, 0.03 part of the compound (a-2) and 0.03 part of the compound (a-3) were used in the same manner as in Example 1 except that the compound (a-2) was used instead of the compound (S). Made the material.

Subsequently, in the same manner as in Example 1, a silica (SiO ₂ ) layer and a titania (TiO ₂ ) layer are alternately laminated on one side of the obtained base material (24 in total). Dielectric multilayer film (XIX) Further, a dielectric multilayer film (XX) is formed by alternately laminating silica (SiO ₂ ) layers and titania (TiO ₂ ) layers on the other surface of the substrate (18 layers in total), An optical filter having a thickness of about 0.106 mm was obtained. The dielectric multilayer film was designed using the same design parameters as in Example 2 in consideration of the wavelength dependence of the refractive index of the substrate. The spectral transmittance of this optical filter was measured, and the optical characteristics in each wavelength region were evaluated. The results are shown in Table 7.

[Comparative Example 4]
As in Example 1, except that a transparent glass substrate “OA-10G (thickness 200 μm)” (manufactured by Nippon Electric Glass Co., Ltd.) cut to a size of 60 mm in length and 60 mm in width was used as the base material. A dielectric multilayer film (XXI) is formed by alternately laminating a silica (SiO ₂ ) layer and a titania (TiO ₂ ) layer on one side of the base material (24 layers in total), and further, the other side of the base material On the surface, a dielectric multilayer film (XXII) is formed by alternately laminating silica (SiO ₂ ) layers and titania (TiO ₂ ) layers (total 20 layers) to obtain an optical filter having a thickness of about 0.206 mm. It was. The dielectric multilayer film was designed using the same design parameters as in Example 1 in consideration of the wavelength dependence of the refractive index of the substrate. The spectral transmittance of this optical filter was measured, and the optical characteristics in each wavelength region were evaluated. The results are shown in Table 7.

[Examples 8 to 13]
A substrate and an optical filter were prepared in the same manner as in Example 5 except that the resin, the solvent, the drying conditions for the resin substrate, the compound (S), and the compound (A) were changed as shown in Table 7. Table 7 shows the optical properties of the obtained substrate and optical filter.

  The configurations of the base materials and various compounds applied in the examples and comparative examples are as follows.

<Form of substrate>
Form (1): Transparent resin substrate containing compound (S) Form (2): Having resin layers on both sides of transparent resin substrate containing compound (S) Form (3): Compound (on both sides of resin substrate) Form (4): having a transparent resin layer containing compound (S) on one surface of a glass substrate Form (5): resin substrate not containing compound (S) (Comparative Example) )
Form (6): Near-infrared absorbing glass substrate (comparative example)
Form (7): Glass substrate (comparative example)

<Transparent resin>
Resin A: Cyclic olefin resin (resin synthesis example 1)
Resin B: Aromatic polyether resin (resin synthesis example 2)
Resin C: Polyimide resin (resin synthesis example 3)
Resin D: Cyclic olefin resin “Zeonor 1420R” (manufactured by Nippon Zeon Co., Ltd.)

<Glass substrate>
Glass substrate (1): Transparent glass substrate “OA-10G (thickness: 200 μm)” cut to 60 mm length and 60 mm width (manufactured by Nippon Electric Glass Co., Ltd.)
Glass substrate (2): Near-infrared absorbing glass substrate “BS-6 (thickness 210 μm)” cut to a size of 60 mm length and 60 mm width (manufactured by Matsunami Glass Industry Co., Ltd.)

<Compound (S)>
Compound (s-5): Compound (s-5) described in Table 1 above (absorption maximum wavelength in dichloromethane: 770 nm)
Compound (s-11): Compound (s-11) described in Table 1 above (absorption maximum wavelength in dichloromethane of 776 nm)
Compound (s-21): Compound (s-21) described in Table 1 above (absorption maximum wavelength of 782 nm in dichloromethane)
Compound (s-23): Compound (s-23) described in Table 1 above (absorption maximum wavelength in dichloromethane of 784 nm)

<Compound (A)>
Compound (a-1): Compound (a-1) (absorption maximum wavelength in dichloromethane: 698 nm)
Compound (a-2): Compound (a-2) (absorption maximum wavelength in dichloromethane of 733 nm)
Compound (a-3): Compound (a-3) (absorption maximum wavelength in dichloromethane: 703 nm)
Compound (a-4): Compound (a-4) (maximum absorption wavelength 736 nm in dichloromethane)

<Solvent>
Solvent (1): Methylene chloride Solvent (2): N, N-dimethylacetamide Solvent (3): Cyclohexane / xylene (weight ratio: 7/3)

<Resin substrate drying conditions>
In Table 7, the drying conditions of the (transparent) resinous substrates of Examples and Comparative Examples are as follows. In addition, the coating film was peeled from the glass plate before drying under reduced pressure.
Condition (1): 20 ° C./8 hr → under reduced pressure 100 ° C./8 hr
Condition (2): 60 ° C./8 hr → 80 ° C./8 hr → under reduced pressure 140 ° C./8 hr
Condition (3): 60 ° C./8 hr → 80 ° C./8 hr → under reduced pressure 100 ° C./24 hr

<Composition for resin layer formation>
The resin composition for forming the resin layer in the examples of Table 7 is as follows.
Resin composition (1) (TSC: 30%): 60 parts by weight of tricyclodecane dimethanol acrylate, 40 parts by weight of dipentaerythritol hexaacrylate, 5 parts by weight of 1-hydroxycyclohexyl phenyl ketone, methyl ethyl ketone (solvent)
Resin composition (2) (TSC: 25%): 100 parts by weight of tricyclodecane dimethanol acrylate, 4 parts by weight of 1-hydroxycyclohexyl phenyl ketone, 0.75 part by weight of compound (s-5), compound (a-2) 0.75 part by weight, compound (a-3) 0.75 part by weight, methyl ethyl ketone (solvent)
Resin composition (3) (TSC: 35%): 20 parts by weight of tricyclodecane dimethanol acrylate, 80 parts by weight of dipentaerythritol hexaacrylate, 4 parts by weight of 1-hydroxycyclohexyl phenyl ketone, compound (s-5) 5 parts by weight, compound (a-2) 1.5 parts by weight, compound (a-3) 1.5 parts by weight, methyl ethyl ketone (solvent)

  The optical filter of the present invention includes a digital still camera, a smartphone camera, a mobile phone camera, a digital video camera, a wearable device camera, a PC camera, a surveillance camera, an automobile camera, a night vision camera, a motion capture, a laser rangefinder, It can be suitably used for virtual try-on, license plate recognition device, television, car navigation, portable information terminal, personal computer, video game machine, portable game machine, fingerprint authentication system, digital music player, and the like.

1: Optical filter 2: Spectrophotometer 3: Light

Claims (13)

An optical filter that selectively transmits visible light and some near infrared rays,
A region having a wavelength of 650 nm or more has a light blocking band Za, a light transmitting band Zb, and a light blocking band Zc, and the center wavelength of each band is Za <Zb <Zc,
At a wavelength of 800 nm, and the transmittance as measured in the vertical direction of the optical filter is more than 20% state, and are transmittance less than 50% as measured from the direction of 30 ° with respect to the vertical direction of the optical filter, And,
Wherein among the Zb, transmittance when measured from a vertical direction of the optical filter is 50% Ru most wavelength values of the short-wavelength side (Xa) is 810~900nm der, an optical filter.   In the wavelength region of 700 to 800 nm, the average value of the transmittance when measured from the vertical direction of the optical filter is 5% or less, and the transmittance when measured from the direction of 30 ° with respect to the vertical direction of the optical filter. The optical filter according to claim 1, wherein an average value is 10% or less.   Of the Zb, the difference Xb between the wavelength value (Xa) on the shortest wavelength side and the wavelength value (Xb) on the longest wavelength side, at which the transmittance is 50% when measured from the vertical direction of the optical filter. The optical filter according to claim 1 or 2, wherein -Xa is 5 to 150 nm, and a value of Y represented by Y = (Xa + Xb) / 2 is 820 to 950 nm. The minimum transmittance when measured from the vertical direction of the optical filter in Za and Zc is 4% or less, respectively, and the maximum transmittance when measured from the vertical direction of the optical filter in Zb is 55% or more. Item 4. The optical filter according to any one of Items 1 to 3 . Of Zb, the transmittance is 50% when measured from the vertical direction of the optical filter. The wavelength value on the shortest wavelength side is Xa, the wavelength value on the longest wavelength side is Xb, and (Xa + Xb) / When the value of 2 is Y,
The optical filter according to any one of claims 1 to 4 , wherein an average transmittance measured from the vertical direction of the optical filter in a wavelength range of Y-10 nm to Y + 10 nm is 60% or more. Wherein the optical filter has a substrate with (i), a transparent resin layer containing the compound (S) to the substrate (i) has an absorption maximum at a wavelength of 750 to 850 nm, claim 1-5 The optical filter according to item 1. The optical filter according to claim 6 , wherein the compound (S) is a compound represented by the following formula (S1).
[In the formula (S1), X independently represents an oxygen atom, a sulfur atom, a selenium atom, a tellurium atom or —NR ⁸ —;
R ^{1 to} R ⁸ are each independently a hydrogen atom, a halogen atom, a sulfo group, a hydroxyl group, a cyano group, a nitro group, a carboxy group, a phosphate group, a —NR ^g R ^h group, a —SO ₂ R ⁱ group, or —OSO. It represents either ₂ R ⁱ group or a group represented by L ^a ~L ^h, are each R ^g and R ^h independently represent any of hydrogen atom, -C (O) R ⁱ groups or the following L ^a ~L ^e , R ⁱ represents any of the following L ^a ~L ^e,
(L ^a ) an aliphatic hydrocarbon group having 1 to 12 carbon atoms (L ^b ) a halogen-substituted alkyl group having 1 to 12 carbon atoms (L ^c ) an alicyclic hydrocarbon group having 3 to 14 carbon atoms (L ^d ) carbon the number 6 to 14 aromatic hydrocarbon group (L ^e) carbon atoms, which may have a number Hajime Tamaki 3 to 14 (L ^f) an alkoxy group having 1 to 12 carbon atoms (L ^g) substituents L carbon 1-12 acyl group (L ^h) alkoxycarbonyl substituent L substituent having 1 to 12 carbon atoms which may have a L is an aliphatic hydrocarbon group having 1 to 12 carbon atoms, carbon atoms from 1 to 12 At least one selected from the group consisting of a halogen-substituted alkyl group, an alicyclic hydrocarbon group having 3 to 14 carbon atoms, an aromatic hydrocarbon group having 6 to 14 carbon atoms, and a heterocyclic group having 3 to 14 carbon atoms. is there. ] The optical filter according to claim 6 or 7 , wherein the transparent resin layer contains, in addition to the compound (S), a compound (A) having an absorption maximum at a wavelength of 600 nm or more and less than 750 nm. The transparent resin layer is a cyclic (poly) olefin resin, aromatic polyether resin, polyimide resin, fluorene polycarbonate resin, fluorene polyester resin, polycarbonate resin, polyamide resin, polyarylate resin, polysulfone resin. Resin, polyethersulfone resin, polyparaphenylene resin, polyamideimide resin, polyethylene naphthalate resin, fluorinated aromatic polymer resin, (modified) acrylic resin, epoxy resin, allyl ester curable type 9. The method according to claim 6 , comprising at least one resin selected from the group consisting of a resin, a silsesquioxane ultraviolet curable resin, an acrylic ultraviolet curable resin, and a vinyl ultraviolet curable resin. The optical filter described. The optical filter according to any one of claims 6 to 9 , which has a dielectric multilayer film on at least one surface of the substrate (i). A solid-state imaging device, an optical filter according to any one of claims 1-10. A solid-state imaging device including an optical filter according to any one of claims 1 to 11. Camera module comprising an optical filter according to any one of claims 1 to 11.