阅读说明：本技术 近红外线截止滤波器及使用所述近红外线截止滤波器的装置 (Near infrared cut filter and device using the same ) 是由 重冈大介 长屋胜也 大月敏敬 于 2018-07-24 设计创作，主要内容包括：本发明的课题在于提供一种近红外线截止特性优异、入射角依存性少、可见波长区域中的透过率特性及近红外波长区域的多重反射光的减少效果优异的近红外线截止滤波器。本发明的近红外线截止滤波器包含具有含有近红外线吸收剂的透明树脂层的基材、以及形成于所述基材的至少一面的介电体多层膜,且满足下述必要条件(a)：(a)在波长600nm～800nm的区域中,自所述基材的垂直方向进行测定时的透过率成为50％的最短波长的值(Xa)、与在波长700nm～1200nm的区域中自基材的垂直方向进行测定时的透过率成为50％的最长波长的值(Xb)的差的绝对值|Xa-Xb|为120nm以上。(The present invention addresses the problem of providing a near-infrared cut filter having excellent near-infrared cut characteristics, little dependence on the angle of incidence, and excellent transmittance characteristics in the visible wavelength range and an excellent effect of reducing multiple reflected light in the near-infrared wavelength range. The near infrared ray cut filter of the present invention comprises a substrate having a transparent resin layer containing a near infrared ray absorber, and a dielectric multilayer film formed on at least one surface of the substrate, and satisfies the following requirement (a): (a) the absolute value | Xa-Xb | of the difference between the value (Xa) of the shortest wavelength at which the transmittance when measured from the perpendicular direction to the substrate is 50% in the region of a wavelength of 600nm to 800nm and the value (Xb) of the longest wavelength at which the transmittance when measured from the perpendicular direction to the substrate is 50% in the region of a wavelength of 700nm to 1200nm is 120nm or more.)

1. A near infrared ray cut filter comprising: a substrate having a transparent resin layer containing a near-infrared absorber, and a dielectric multilayer film formed on at least one surface of the substrate, and satisfying the following requirement (a):

(a) the absolute value | Xa-Xb | of the difference between the shortest wavelength value (Xa) having a transmittance of 50% when measured from the direction perpendicular to the substrate in the region of a wavelength of 600nm to 800nm and the longest wavelength value (Xb) having a transmittance of 50% when measured from the direction perpendicular to the substrate in the region of a wavelength of 700nm to 1200nm is 120nm or more.

2. The near-infrared cut filter according to claim 1, wherein an average value (Ta) of transmittances measured from a direction perpendicular to the substrate in the region of the wavelengths Xa to Xb is 35% or less.

3. The near-infrared cut filter according to claim 1 or 2, further satisfying the following requirement (b):

(b) in the wavelength range of 560nm to 800nm, the absolute value | Ya-Yb | of the difference between the value (Ya) of the shortest wavelength at which the transmittance when measured from the vertical direction of the near infrared cut filter becomes 50% and the value (Yb) of the shortest wavelength at which the transmittance when measured from an angle of 30 DEG with respect to the vertical direction of the near infrared cut filter becomes 50% is less than 15 nm.

4. The near-infrared cut filter according to any one of claims 1 to 3, wherein the near-infrared absorber is at least one selected from the group consisting of a squarylium compound, a phthalocyanine compound, a naphthalocyanine compound, a ketanium compound, and a cyanine compound.

5. The near infrared ray cut filter according to any one of claims 1 to 4, wherein the transparent resin layer contains two or more kinds of the near infrared ray absorbers.

6. The near-infrared cut filter according to any one of claims 1 to 5, wherein the near-infrared absorber comprises a squarylium salt-based compound (A) having a maximum absorption at a wavelength of 650nm to 750nm and a compound (B) having a maximum absorption at a wavelength of 660nm to 850nm (excluding the compound (A)).

7. The near-infrared cut filter according to any one of claims 1 to 6, wherein the dielectric multilayer film is formed on both surfaces of the substrate.

8. The near-infrared cut filter according to claim 7, wherein the dielectric multilayer film formed on both surfaces of the base material comprises a near-infrared reflecting film and a visible light antireflection film.

9. The near-infrared cut filter according to any one of claims 1 to 8, wherein in a region of a wavelength of 600nm to 900nm, a value (Xr) of a shortest wavelength at which a reflectance becomes 50% when measured at an angle of 30 ° with respect to a perpendicular direction of any one surface of the near-infrared cut filter is 620nm or more.

10. The near-infrared cut filter according to any one of claims 1 to 9, wherein the transparent resin is at least one resin selected from the group consisting of a cyclic (poly) olefin-based resin, an aromatic polyether-based resin, a polyimide-based resin, a fluorene polycarbonate-based resin, a fluorene polyester-based resin, a polycarbonate-based resin, a polyamide-based resin, a polyarylate-based resin, a polysulfone-based resin, a polyethersulfone-based resin, a polyphenylene-based resin, a polyamideimide-based resin, a polyethylene naphthalate-based resin, a fluorinated aromatic polymer-based resin, (a modified) acrylic resin, an epoxy-based resin, an allyl-based curing resin, a silsesquioxane-based ultraviolet curing resin, an acrylic-based ultraviolet curing resin, and a vinyl-based ultraviolet curing resin.

11. The near-infrared cut filter according to any one of claims 1 to 10, wherein the base material contains at least one selected from a transparent resin support and a glass support.

12. The near-infrared cut filter according to any one of claims 1 to 11, used for a solid-state imaging device.

13. A solid-state imaging device comprising the near-infrared ray cut filter according to any one of claims 1 to 12.

14. A camera module comprising the near infrared ray cut filter according to any one of claims 1 to 12.

15. A method for manufacturing a near-infrared cut filter, comprising a step of forming a dielectric multilayer film on at least one surface of a substrate having a transparent resin layer containing a near-infrared absorber, the method comprising: the near infrared ray cut filter satisfies the following requirement (a):

(a) the absolute value | Xa-Xb | of the difference between the shortest wavelength value (Xa) having a transmittance of 50% when measured from the direction perpendicular to the substrate in the region of a wavelength of 600nm to 800nm and the longest wavelength value (Xb) having a transmittance of 50% when measured from the direction perpendicular to the substrate in the region of a wavelength of 700nm to 1200nm is 120nm or more.

Technical Field

The present invention relates to a near-infrared cut filter and a device using the same. More specifically, the present invention relates to a near-infrared cut filter including a dye compound having absorption in a specific wavelength region, and a solid-state imaging device and a camera module using the near-infrared cut filter.

Background

In solid-state imaging devices such as video cameras, digital still cameras, and mobile phones with camera functions, Charge Coupled Device (CCD) image sensors or Complementary Metal Oxide Semiconductor (CMOS) image sensors are used as solid-state imaging elements for color images, and these solid-state imaging elements use silicon photodiodes (silicon photodiodes) having sensitivity to near infrared rays that cannot be perceived by the human eye in their light receiving sections. In these solid-state imaging devices, it is necessary to correct the visual sensitivity so that the color tone becomes natural when viewed by the human eye, and near infrared cut filters that selectively transmit or cut light in a specific wavelength range are often used.

As such a near infrared ray cut filter, a near infrared ray cut filter manufactured by various methods has been used heretofore. For example, a near-infrared cut filter is known in which a transparent resin is used as a base material and a near-infrared absorbing dye is contained in the transparent resin (see, for example, patent document 1).

However, the near-infrared cut filter described in patent document 1 cannot expand the absorption range width of the base material while maintaining the visible light transmittance at a high level, and in order to sufficiently reduce the transmittance in the vicinity of 700nm to 800nm, it is necessary to position the cut-off wavelength of the dielectric multilayer film on the shorter wavelength side.

The near infrared ray cut filter incorporated in the camera module is used in an arrangement in which a dielectric multilayer film (near infrared ray reflective film) is provided on the lens side and an antireflection film is provided on the image sensor side, but there is a case where multiple reflection is caused by reflected light between the dielectric multilayer film and the lens, and as a result, there are cases in which: multiple reflected lights of around 700nm to 800nm, which have high sensor sensitivity, enter the imaging element, and the camera image deteriorates.

However, the near-infrared cut filter described in patent document 1 does not have a sufficient light absorption range in the near-infrared region, and it is necessary to increase the near-infrared reflectance of the near-infrared cut filter when the light incident on the sensor from the near-infrared light is sufficiently cut.

Further, with the miniaturization of camera modules in mobile devices, the incident angle of light rays tends to become larger particularly at the end of the screen than before, and in the near infrared cut filter before, ghost caused by multiple reflection between the near infrared cut filter and the lens may become a problem. Specifically, as shown in fig. 1, of the incident light transmitted through the lens 4, visible light is transmitted through the near infrared ray cut filter 1, and near infrared light is reflected (reflected light 3A). The reflected near-infrared light is reflected again at the surface of the lens 4 (reflected light 3B), causing multiple reflection. There is a case where multiple reflected light (transmitted light 3C) between the near infrared cut filter and the lens enters the sensor 5, and the camera image is deteriorated.

Disclosure of Invention

Problems to be solved by the invention

In recent years, the image quality level required for camera images in mobile devices and the like has also become very high. According to the studies of the present inventors, in order to satisfy the demand for high image quality, in the near infrared cut filter, high light cut characteristics are required in a long wavelength region in addition to a wide viewing angle and high visible light transmittance. However, as described above, in the conventional near infrared cut filter, there is a case where ghost caused by multiple reflection becomes a problem.

The present invention addresses the problem of providing a near-infrared cut filter having excellent near-infrared cut characteristics, little dependence on the angle of incidence, and excellent transmittance characteristics in the visible wavelength range and an excellent effect of reducing multiple reflected light in the near-infrared wavelength range.

Means for solving the problems

The present applicant has made extensive studies to solve the above problems, and as a result, has found that a near infrared cut filter which is less in change of optical characteristics and less in image degradation due to multiple reflection even when an incident angle is changed can be obtained by extending the absorption range width of a base material to the near infrared region, and has completed the present invention. Examples of the scheme of the present invention are shown below.

[1] A near-infrared cut filter comprising a substrate having a transparent resin layer containing a near-infrared absorber and a dielectric multilayer film formed on at least one surface of the substrate, and satisfying the following requirement (a):

(a) the absolute value | Xa-Xb | of the difference between the shortest wavelength value (Xa) having a transmittance of 50% when measured from the direction perpendicular to the substrate in the region of a wavelength of 600nm to 800nm and the longest wavelength value (Xb) having a transmittance of 50% when measured from the direction perpendicular to the substrate in the region of a wavelength of 700nm to 1200nm is 120nm or more.

[2] The near-infrared cut filter according to item [1], wherein an average value (Ta) of transmittances measured from a direction perpendicular to the substrate in the region of the wavelengths Xa to Xb is 35% or less.

[3] The near-infrared cut filter according to the item [1] or the item [2], further satisfying the following requirement (b):

(b) in the wavelength range of 560nm to 800nm, the absolute value | Ya-Yb | of the difference between the value (Ya) of the shortest wavelength at which the transmittance when measured from the vertical direction of the near infrared cut filter becomes 50% and the value (Yb) of the shortest wavelength at which the transmittance when measured from an angle of 30 DEG with respect to the vertical direction of the near infrared cut filter becomes 50% is less than 15 nm.

[4] The near-infrared cut filter according to any one of the items [1] to [3], wherein the near-infrared absorber is at least one selected from the group consisting of squarylium (squarylium) based compounds, phthalocyanines (phthalocyanines) based compounds, naphthalocyanines (naphthalocyanines) based compounds, crotonium (croconium) based compounds, and cyanine (cyanine) based compounds.

[5] The near-infrared ray cut filter according to any one of the items [1] to [4], wherein the transparent resin layer contains two or more kinds of the near-infrared ray absorbers.

[6] The near-infrared ray cut filter according to any one of the items [1] to [5], wherein the near-infrared ray absorber contains a squarylium salt-based compound (A) having a maximum absorption in a wavelength of 650nm to 750nm and a compound (B) having a maximum absorption in a wavelength of 660nm to 850nm (excluding the compound (A)).

[7] The near-infrared ray cut filter according to any one of the items [1] to [6], wherein the dielectric multilayer film is formed on both surfaces of the substrate.

[8] The near infrared ray cut filter according to item [7], wherein the dielectric multilayer film formed on both surfaces of the base material comprises a near infrared ray reflective film and a visible light antireflection film.

[9] The near-infrared cut filter according to any one of the items [1] to [8], wherein in a region of a wavelength of 600nm to 900nm, a value (Xr) of a shortest wavelength at which a reflectance when measured at an angle of 30 ° with respect to a perpendicular direction to any one surface of the near-infrared cut filter becomes 50% is 620nm or more.

[10] The near-infrared cut filter according to any one of items [1] to [9], wherein the transparent resin is at least one resin selected from the group consisting of a cyclic (poly) olefin-based resin, an aromatic polyether-based resin, a polyimide-based resin, a fluorene polycarbonate-based resin, a fluorene polyester-based resin, a polycarbonate-based resin, a polyamide-based resin, a polyarylate-based resin, a polysulfone-based resin, a polyethersulfone-based resin, a polyphenylene-based resin, a polyamideimide-based resin, a polyethylene naphthalate-based resin, a fluorinated aromatic polymer-based resin, (a modified) acrylic-based resin, an epoxy-based resin, an allyl-based cured resin, a silsesquioxane-based ultraviolet cured resin, an acrylic-based ultraviolet cured resin, and a vinyl-based ultraviolet cured resin.

[11] The near-infrared cut filter according to any one of the items [1] to [10], wherein the base material contains at least one selected from a transparent resin support and a glass support.

[12] The near-infrared cut filter according to any one of the items [1] to [11], which is used for a solid-state imaging device.

[13] A solid-state imaging device comprising the near-infrared cut filter according to any one of the items [1] to [12 ].

[14] A camera module provided with the near-infrared cut filter according to any one of the items [1] to [12 ].

[15] A method for manufacturing a near-infrared cut filter, comprising a step of forming a dielectric multilayer film on at least one surface of a substrate having a transparent resin layer containing a near-infrared absorber, the method comprising: the near infrared ray cut filter satisfies the following requirement (a):

(a) the absolute value | Xa-Xb | of the difference between the shortest wavelength value (Xa) having a transmittance of 50% when measured from the direction perpendicular to the substrate in the region of a wavelength of 600nm to 800nm and the longest wavelength value (Xb) having a transmittance of 50% when measured from the direction perpendicular to the substrate in the region of a wavelength of 700nm to 1200nm is 120nm or more.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, a near-infrared cut filter having excellent near-infrared cut characteristics, small incident angle dependency, and excellent transmittance characteristics in the visible wavelength region and reduction effects of multiple reflected lights in the near-infrared wavelength region can be provided.

Drawings

Fig. 1 is a schematic view showing a solid-state imaging device on which light rays multiply reflected between a near infrared ray cut filter and a lens are incident.

Fig. 2(a) is a schematic diagram showing a method of measuring the transmittance in the vertical direction of the near-infrared cut filter. Fig. 2(b) is a schematic diagram showing a method of measuring the transmittance when the measurement is performed from an angle of 30 ° with respect to the vertical direction of the near-infrared cut filter. Fig. 2(c) is a schematic diagram showing a method for measuring the reflectance from an angle of 30 ° with respect to the vertical direction of the near-infrared cut filter.

Fig. 3(a) and 3(b) are schematic diagrams showing a preferred configuration example of the near-infrared cut filter of the present invention.

Fig. 4 is a spectral transmittance spectrum of the substrate obtained in example 1.

FIG. 5(a) is a spectral reflectance spectrum measured at an angle of 5 ℃ relative to the vertical direction of the dielectric multilayer film (I) formed in example 1, and FIG. 5(b) is a spectral reflectance spectrum measured at an angle of 5 ℃ relative to the vertical direction of the dielectric multilayer film (II) formed in example 1.

Fig. 6 shows the spectral transmission spectrum of the near-infrared cut filter obtained in example 1.

FIG. 7 is a spectral reflectance spectrum measured from an angle of 30 ℃ with respect to the perpendicular direction of the near infrared ray cut filter when the incident surface of the light ray is on the side of the dielectric multilayer film (II) (second optical layer) in the near infrared ray cut filter obtained in example 1.

Fig. 8 is a spectral transmittance spectrum of the substrate obtained in example 2.

Fig. 9 shows the spectral transmission spectrum of the near-infrared cut filter obtained in example 2.

FIG. 10 is a spectral reflectance spectrum measured from an angle of 30 ℃ with respect to the perpendicular direction of the near infrared ray cut filter when the incident surface of the light ray is on the dielectric multilayer film (IV) (second optical layer) side with respect to the near infrared ray cut filter obtained in example 2.

Fig. 11 is a schematic diagram for explaining evaluation of the hue of the camera images performed in the examples and comparative examples.

Detailed Description

The present invention will be specifically described below.

[ near Infrared ray cut-off Filter ]

The near infrared ray cut filter of the present invention is characterized in that: comprises a substrate (i) having a transparent resin layer containing a near-infrared absorber, and a dielectric multilayer film formed on at least one surface of the substrate (i), and satisfies the following requirement (a).

Requirement (a);in the region of 600nm to 800nm, the absolute value (absorption half width) | Xa-Xb | of the difference between the value (Xa) of the shortest wavelength at which the transmittance when measured from the vertical direction of the substrate (i) becomes 50% and the value (Xb) of the longest wavelength at which the transmittance when measured from the vertical direction of the substrate (i) becomes 50% in the region of 700nm to 1200nm is 120nm or more.

The near-infrared cut filter of the present invention has excellent near-infrared cut characteristics, less dependence on incident angle, and excellent transmittance characteristics in the visible wavelength region and an excellent effect of reducing multiple reflected light in the near-infrared wavelength region.

And a near infrared cut filter having an excellent effect of reducing multiple reflections in the near infrared region when the transmittance in the wavelength region from Xa to Xb is large.

When the near-infrared cut filter of the present invention is used for a solid-state imaging device, the transmittance in the near-infrared wavelength region is preferably low. In particular, it is known that the light receiving sensitivity of the solid-state imaging device is high in the wavelength region of 700nm to 1000nm, and the reduction of the transmittance in the wavelength region enables effective correction of the visual sensitivity of the camera image and the human eye, thereby achieving excellent color reproducibility.

The near-infrared cut filter of the present invention has an average transmittance of 5% or less, preferably 4% or less, more preferably 3% or less, and particularly preferably 2% or less, measured from a direction perpendicular to the filter, in a region having a wavelength of 700nm to 1000 nm. When the average transmittance at a wavelength of 700nm to 1000nm is in the above range, the near infrared ray can be sufficiently cut off, and excellent color reproducibility can be achieved, which is preferable.

When the near-infrared cut filter of the present invention is used for a solid-state imaging device or the like, the visible light transmittance is preferably high. Specifically, the average transmittance measured from the direction perpendicular to the near infrared cut filter in the region of a wavelength of 430nm to 580nm is preferably 75% or more, more preferably 80% or more, still more preferably 83% or more, and particularly preferably 85% or more. When the average transmittance in the wavelength region is in the above range, excellent imaging sensitivity can be achieved when the near-infrared cut filter of the present invention is used for a solid-state imaging device.

The near-infrared cut filter of the present invention preferably further satisfies the following requirement (b).

Requirement (b);in the wavelength range of 560nm to 800nm, the absolute value | Ya-Yb | of the difference between the value (Ya) of the shortest wavelength at which the transmittance when measured from the vertical direction of the near infrared ray cut filter becomes 50% and the value (Yb) of the shortest wavelength at which the transmittance when measured from the angle of 30 DEG with respect to the vertical direction of the near infrared ray cut filter becomes 50% is less than 15 nm.

The absolute value | Ya-Yb | is more preferably less than 10nm, and particularly preferably less than 5 nm. When a near-infrared cut filter satisfying the requirement (b) is used for a solid-state imaging device, the transmittance change depending on the incident angle is small, and the color shading of the image is good. Such a near infrared ray cut filter can be obtained by forming a dielectric multilayer film on the substrate (i).

In the near-infrared cut filter, the values of L, a, and b in the color system are preferred. Here, the "L × a × b color system" is defined by the commission international commission on illumination de L' Eclairage (CIE) project. "L" is referred to as "luminance index" and indicates luminance, and "a" and "b" are referred to as "chromaticity (chroma) index" and indicate positions corresponding to hue and chroma. Regarding the hue and chroma, if a is negative, the hue and chroma are green-based colors, and if a is positive, the hue and chroma are red-based colors. When b is negative, it is a blue color, and when b is positive, it is a yellow color. When used in a camera module, L × a × b × the color system of the near infrared cut filter preferably falls within a certain range of values, because "a × b value" and "L × value" affect the brightness and color of a camera image.

In the present invention, "value of L" "" value of a "" "value of b" "" in the color system "is set to the following value: the transmittance at 380nm to 780nm was measured from the perpendicular direction (incident angle 0 ℃) of a near infrared ray cut filter using a spectrophotometer "U-4100" manufactured by Hitachi High-technologies, Ltd.

The value of L in the color system is preferably 70 or more, and more preferably 80 or more. When a near infrared ray cut filter having a value of L in the above range is used for a solid-state imaging device, a visual evaluation of the color reproducibility of the obtained image shows a good result.

The value of a in the L × a × b color system is preferably-31 or more and 5 or less, more preferably-25 or more and-2 or less, and still more preferably-21 or more and-5 or less. In addition, the value of b in the L × a × b color system is preferably-5 to 10. If the values of a and b in the L a b color system are in the ranges, the visual evaluation of the color reproducibility of the obtained images shows good results.

From an angle of 30 ° with respect to the perpendicular direction of the near infrared ray cut filter (incident angle 30 °), the transmittance of 380nm to 780nm was measured in the same manner as described above to obtain the value in the L a b table color system, and the value of L, a, and b at this time were set to the value of "L" (30 °), the value of "a" (30 °), and the value of "b" (30 °), and the absolute value of the difference | △ L |, | △ a |, and | △ b |, respectively, from the incident angle 0 °, the absolute value | △ L |, the absolute value of |, and △ a |, and the absolute value of the difference | △ b |, can be calculated by the following formula.

| △ L | (value of L (30 °)) - (value of L) | ceiling

| △ a | (value of a (30 °)) - (value of a) |

| △ b | (value of b (30 °)) - (value of b) | ceiling

When a near-infrared cut filter having | △ a | and | △ b | within the above-described range is used for a solid-state imaging device, visual evaluation of the color reproducibility of the obtained image shows a good result.

In the near-infrared cut filter of the present invention, since the surface of the substrate (i) on the lens side has a low reflectance in the region of a wavelength of 700nm to 800nm, reflection of light between the near-infrared cut filter and the lens can be reduced.

In the region of a wavelength of 700nm to 800nm, the minimum value of the reflectance when measured from an angle of 30 ° with respect to the perpendicular direction of at least one surface of the near infrared ray cut filter is preferably 80% or less, more preferably 50% or less, and particularly preferably 10% or less. When the reflectance is in such a range, various ghosts derived from multiple reflected light tend to be reduced particularly when the reflectance is used in a solid-state imaging device, and therefore the reflectance is preferable.

Here, the ghost intensity by multiple reflection is explained with reference to fig. 1. The light transmitted through the lens 4 is partially reflected by the near infrared ray cut filter 1 (reflected light 3A), is further reflected by the lens surface (reflected light 3B), is transmitted through the near infrared ray cut filter 1 (transmitted light 3C), and reaches the surface of the sensor 5. Therefore, regarding the ghost intensity by multiple reflection between the near infrared ray cut filter and the lens, when the average reflectance measured from the direction of 30 ° with respect to the perpendicular direction of the near infrared ray cut filter in the range of 700nm to 850nm is (a)%, the average reflectance of the lens in the range of 700nm to 850nm is (b)%, and the average transmittance measured from the direction of 30 ° with respect to the perpendicular direction in the range of 700nm to 850nm is (c)%, the ghost intensity can be calculated by the following formula.

[ ghost intensity ] ═ a (a) × (b) × (c)

In the present invention, the average reflectance (b) of the lens in the range of 700nm to 850nm is calculated as 1%.

The ghost intensity by multiple reflection calculated by the above formula is preferably 0.300 or less, more preferably 0.100 or less, and further preferably 0.060 or less. When the near infrared ray cut filter of such ghost intensity is used in a camera, a visual evaluation of the color reproducibility of the obtained image shows a good result.

The thickness of the near-infrared cut filter of the present invention may be appropriately selected depending on the intended use, and is preferably thin in accordance with the recent trend toward thinner and lighter solid-state imaging devices. The near-infrared cut filter of the present invention can be made thin because it includes the base material (i).

The thickness of the near-infrared cut filter of the present invention is preferably 200 μm or less, more preferably 180 μm or less, further preferably 150 μm or less, particularly preferably 120 μm or less, and the lower limit is not particularly limited, but is preferably 20 μm, for example.

When the thickness of the resin substrate is within the above range, the near-infrared cut filter using the substrate can be reduced in size and weight, and thus the resin substrate can be preferably used for various applications such as a solid-state imaging device. In particular, when the resin substrate is used for a lens unit (lens unit) of a camera module or the like, it is preferable because the lens unit can be made lower in back.

[ base Material (i) ]

The substrate (i) has a transparent resin layer containing a near-infrared absorber. Examples of the near-infrared absorber include: and (c) a squarylium salt-based compound (A) having a maximum absorption at a wavelength of 650 to 750nm (hereinafter also referred to as "compound (A)") and a compound (B) having a maximum absorption at a wavelength of 660 to 850nm (except for the compound (A) ", hereinafter also referred to as" compound (B) "), and the like.

The substrate (i) may be a single layer or a plurality of layers. When the base material (i) is a single layer, for example, there can be mentioned a base material comprising a transparent resin substrate (ii) containing the compound (a) and the compound (B), the transparent resin substrate (ii) being the transparent resin layer. When the substrate (i) is a multilayer, for example, there may be mentioned: a substrate in which a transparent resin layer such as an overcoat layer containing a curable resin or the like containing the compound (a) and the compound (B) is laminated on a support such as a glass support or a resin support serving as a base, a substrate in which a resin layer such as an overcoat layer containing a curable resin or the like containing the compound (a) is laminated on a transparent resin substrate (iii) containing the compound (B), a substrate in which a resin layer such as an overcoat layer containing a curable resin or the like containing the compound (B) is laminated on a transparent resin substrate (iv) containing the compound (a), and a substrate in which a resin layer such as an overcoat layer containing a curable resin or the like is laminated on a transparent resin substrate (ii) containing the compound (a) and the compound (B), and the like. In particular, a substrate in which a resin layer such as an overcoat layer containing a curable resin is laminated on a transparent resin substrate (ii) containing a compound (a) and a compound (B) is preferable in terms of manufacturing cost, ease of adjustment of optical characteristics, and the effect of removing scratches of a resin support or the transparent resin substrate (ii) and improvement in scratch resistance of the substrate (i).

Hereinafter, the layer containing at least one near-infrared absorber and a transparent resin is also referred to as a "transparent resin layer", and the other resin layers are also referred to as "resin layers".

The absolute value | Xa-Xb | in the above requirement (a) is preferably 120nm or more, more preferably 160nm or more, and particularly preferably 180nm or more. When the | Xa-Xb | of the substrate (i) falls within this range, the reflectance in the vicinity of 700nm to 800nm can be reduced when the dielectric multilayer film is formed on the substrate (i), and thus the multiple reflection of light in the above region can be reduced. In particular, when the optical film is used for a solid-state imaging device, various ghosts derived from multiple reflected lights tend to be reduced.

In the region of wavelengths Xa to Xb, the average value (Ta) of the transmittances measured from the perpendicular direction to the substrate (i) is preferably 35% or less, more preferably 30% or less, still more preferably 25% or less, and particularly preferably 20% or less. When (Ta) of the substrate (i) falls within such a range, the reflectance in the vicinity of 700nm to 800nm can be more preferably reduced when the dielectric multilayer film is formed on the substrate (i). In particular, when the optical film is used for a solid-state imaging device, various ghosts derived from multiple reflected lights tend to be reduced.

< near Infrared ray absorber >

The near-infrared absorber is not particularly limited as long as it is a compound having a maximum absorption at a wavelength of 650nm or more and 850nm or less, and a solvent-soluble dye compound is preferable from the viewpoint of suppressing aggregation in the resin. Examples of such near-infrared absorbers include: squarylium compounds, phthalocyanine compounds, naphthalocyanine compounds, ketanium compounds, and cyanine compounds. In the present invention, the compound (a) and the compound (B) are preferably contained as a near-infrared absorber.

Compound (A)

The compound (A) is not particularly limited as long as it is a squarylium salt-based compound having an absorption maximum at a wavelength of 650nm to 750 nm. The squarylium salt compound has excellent visible light transmittance, steep absorption characteristics, and a high molar absorption coefficient, but sometimes generates fluorescence that causes scattered light when absorbing light. In this case, by using the compound (a) and the compound (B) in combination, a near infrared cut filter with less scattered light and better camera image quality can be obtained.

The maximum absorption wavelength of the compound (A) is preferably 650nm to 748nm, more preferably 655nm to 745nm, and particularly preferably 660nm to 740 nm.

The specific example of the compound (A) preferably contains at least one selected from the group consisting of the squarylium salt-based compound represented by the formula (A-I) and the squarylium salt-based compound represented by the formula (A-II). Hereinafter, the compounds are also referred to as "compound (A-I)" and "compound (A-II)", respectively.

[ solution 1]

In the formula (A-I), R^a、R^bAnd Y satisfies the following condition (A-i) or (A-ii).

Condition (A-i)

Plural R^aEach independently represents a hydrogen atom, a halogen atom, a sulfo group, a hydroxyl group, a cyano group, a nitro group, a carboxyl group, a phosphoric acid group, -L¹or-NR^eR^fAnd (4) a base. R^eAnd R^fEach independently represents a hydrogen atom, -L^a、-L^b、-L^c、-L^dor-L^e。

Plural R^bEach independently represents a hydrogen atom, a halogen atom, a sulfo group, a hydroxyl group, a cyano group, a nitro group, a carboxyl group, a phosphoric acid group, -L¹or-NR^gR^hAnd (4) a base. R^gAnd R^hEach independently represents a hydrogen atom, -L^a、-L^b、-L^c、-L^d、-L^eor-C (O) RⁱRadical (R)ⁱIs represented by-L^a、-L^b、-L^c、-L^dor-L^e)。

Plural Y's each independently represent-NR^jR^kAnd (4) a base. R^jAnd R^kEach independently represents a hydrogen atom, -L^a、-L^b、-L^c、-L^dor-L^e。

L¹Is L^a、L^b、L^c、L^d、L^e、L^f、L^gOr L^h。

Said L^a～L^hTo represent

(L^a) An aliphatic hydrocarbon group having 1 to 9 carbon atoms which may have a substituent L,

(L^b) A halogen-substituted alkyl group having 1 to 9 carbon atoms which may have a substituent L,

(L^c) An alicyclic hydrocarbon group having 3 to 14 carbon atoms which may have a substituent L,

(L^d) An aromatic hydrocarbon group having 6 to 14 carbon atoms which may have a substituent L,

(L^e) A heterocyclic group having 3 to 14 carbon atoms and optionally having a substituent L,

(L^f) An alkoxy group having 1 to 9 carbon atoms which may have a substituent L,

(L^g) An acyl group having 1 to 9 carbon atoms and optionally having a substituent L, or

(L^h) An alkoxycarbonyl group having 1 to 9 carbon atoms which may have a substituent L.

The substituent L is at least one selected from the group consisting of an aliphatic hydrocarbon group having 1 to 9 carbon atoms, an alkyl group substituted with a halogen having 1 to 9 carbon atoms, 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.

Said L^a～L^hThe resin composition may further contain at least one atom or group selected from the group consisting of a halogen atom, a sulfo group, a hydroxyl group, a cyano group, a nitro group, a carboxyl group, a phosphoric acid group and an amino group.

Said L^a～L^hThe total number of carbon atoms including the substituents is preferably 50 or less, more preferably 40 or less, and particularly preferably 30 or less. When the number of carbon atoms is more than the above range, the synthesis of the pigment may become difficult, and the absorption strength per unit weight tends to be small.

Condition (A-ii)

One isTwo R on the benzene ring^aIs bonded to Y on the same benzene ring to form a heterocyclic ring having 5 or 6 constituent atoms containing at least one nitrogen atom, which may have a substituent, R^bAnd R not involved in the formation of said heterocyclic ring^aEach independently of R of said (A-i)^bAnd R^aAre the same meaning.

[ solution 2]

In the formula (A-II), X represents O, S, Se, N-R^cOr C-R^dR^d(ii) a Plural R^cEach independently represents a hydrogen atom, -L^a、-L^b、-L^c、-L^dor-L^e(ii) a Plural R^dEach independently represents a hydrogen atom, a halogen atom, a sulfo group, a hydroxyl group, a cyano group, a nitro group, a carboxyl group, a phosphoric acid group, -L¹or-NR^eR^fAnd adjacent R^dMay be linked to each other to form a ring which may have a substituent; l is^a～L^e、L¹、R^eAnd R^fAnd L as defined in said formula (A-I)^a～L^e、L¹、R^eAnd R^fAre the same meaning.

The compound (A-I) and the compound (A-II) can be represented by the following methods using resonance structures, such as the following formula (A-I-2) and the following formula (A-II-2), in addition to the following methods described for the formula (A-I-1) and the following formula (A-II-1). That is, the difference between the following formula (A-I-1) and the following formula (A-I-2) and the difference between the following formula (A-II-1) and the following formula (A-II-2) are only the description of the structure, and the compounds are the same. In the present invention, unless otherwise specified, the structure of the squarylium salt compound is represented by the following description methods such as the following formula (A-I-1) and the following formula (A-II-1).

[ solution 3]

The structures of the compound (I) and the compound (A-II) are not particularly limited as long as they satisfy the requirements of the formula (A-I) and the formula (A-II), respectively, and for example, in the case where the structures are represented by the formula (A-I-1) and the formula (A-II-1), the substituents on the left and right sides of the central four-membered ring may be the same or different, and the same is easy to synthesize, and therefore, preferred. Further, for example, a compound represented by the following formula (A-I-3) and a compound represented by the following formula (A-I-4) can be regarded as the same compound.

[ solution 4]

The content of the compound (a) is, for example, preferably 0.01 to 2.0 parts by weight, more preferably 0.015 to 1.50 parts by weight, and particularly preferably 0.02 to 1.00 parts by weight, based on 100 parts by weight of the transparent resin, in the case of using, as the substrate (i), a substrate including a transparent resin substrate (ii) containing the compound (a) and the compound (B), or a substrate in which a resin layer such as an overcoat layer containing a curable resin containing the compound (B) is laminated on a transparent resin substrate (iv) containing the compound (a). When a substrate in which a transparent resin layer such as a top coat layer containing a curable resin or the like containing the compound (a) and the compound (B) is laminated on a glass support or a resin support as a base or a substrate in which a transparent resin layer such as a top coat layer containing a curable resin or the like containing the compound (a) is laminated on a transparent resin substrate (iii) containing the compound (B) is used as the substrate (i), the amount of the substrate is preferably 0.1 to 5.0 parts by weight, more preferably 0.2 to 4.5 parts by weight, and particularly preferably 0.3 to 4.0 parts by weight, based on 100 parts by weight of the resin forming the transparent resin layer containing the compound (a).

Compound (B)

The compound (B) is not particularly limited as long as it has a maximum absorption at a wavelength of 660nm to 850nm, and is preferably a solvent-soluble dye compound, more preferably at least one selected from the group consisting of squarylium salt compounds, phthalocyanine compounds, cyanine compounds, naphthalocyanine compounds, and ketanium compounds, and further preferably squarylium salt compounds and phthalocyanine compounds. By using such a compound (B), a high near infrared ray cut-off property in the vicinity of the maximum absorption and a good visible light transmittance can be simultaneously achieved.

The maximum absorption wavelength of the compound (B) is preferably 680nm to 830nm, more preferably 700nm to 820nm, and particularly preferably 720nm to 800 nm. When the maximum absorption wavelength of the compound (B) is in such a range, unnecessary near infrared rays causing various ghosts can be efficiently cut off.

The structure of the phthalocyanine-based compound is not particularly limited, and examples thereof include compounds represented by the following formula (III).

[ solution 5]

In the formula (III), M represents two hydrogen atoms, two monovalent metal atoms, a divalent metal atom or a substituted metal atom containing a trivalent or tetravalent metal atom,

plural R_a、R_b、R_cAnd R_dEach independently represents a group selected from a hydrogen atom, a halogen atom, a hydroxyl group, a carboxyl group, a nitro group, an amino group, an amido group, an imido group, a cyano group, a silyl group and-L¹、-S-L²、-SS-L²、-SO₂-L³、-N＝N-L⁴Or R_aAnd R_b、R_bAnd R_cAnd R_cAnd R_dAt least one group of the groups consisting of the groups represented by the following formulae (A) to (H) bonded to at least one of the groups in combination is bonded to R of the same aromatic ring_a、R_b、R_cAnd R_dIs not a hydrogen atom.

The amino group, amide group, imide group and silane group may have a substituent L as defined in the formula (A-I),

L¹and said formula(I) L as defined in (1)¹Are used in the same sense and have the same meaning,

L²represents a hydrogen atom or L as defined in said formula (A-I)^a～L^eAny one of the above-mentioned (A) and (B),

L³represents a hydroxyl group or the L^a～L^eAny one of the above-mentioned (A) and (B),

L⁴represents said L^a～L^eAny of the above.

[ solution 6]

In the formulae (A) to (H), R_xAnd R_yIn combination of R_aAnd R_b、R_bAnd R_cOr R_cAnd R_dIn the combination of (a) and (b),

plural R_A～R_LEach independently represents a hydrogen atom, a halogen atom, a hydroxyl group, a nitro group, an amino group, an amido group, an imido group, a cyano group, a silyl group or-L¹、-S-L²、-SS-L²、-SO₂-L³、-N＝N-L⁴，

The amino group, amide group, imide group and silane group may have the substituent L, L¹～L⁴And L as defined in said formula (III)¹～L⁴Are the same meaning.

The structure of the naphthalocyanine compound is not particularly limited, and examples thereof include compounds represented by the following formula (IV).

[ solution 7]

In the formula (IV), M is the same as M in the formula (7), and R_a、R_b、R_c、R_d、R_eAnd R_fEach independently represents a hydrogen atom, a halogen atom, a hydroxyl group, a carboxyl group, a nitro group, an amino group, an amido group, an imido group, a cyano group, a silyl group or-L¹、-S-L²、-SS-L²、-SO₂-L³、-N＝N-L⁴。

The structure of the cyanine compound is not particularly limited, and examples thereof include compounds represented by the following formulas (V-1) to (V-3).

[ solution 8]

In the formulae (V-1) to (V-3), X_a ^-Represents a monovalent anion of a cation of the formula,

a plurality of D's independently represent a carbon atom, a nitrogen atom, an oxygen atom or a sulfur atom,

plural R_a、R_b、R_c、R_d、R_e、R_f、R_g、R_hAnd R_iEach independently represents a group selected from a hydrogen atom, a halogen atom, a hydroxyl group, a carboxyl group, a nitro group, an amino group, an amido group, an imido group, a cyano group, a silyl group and-L¹、-S-L²、-SS-L²、-SO₂-L³、-N＝N-L⁴Or R_bAnd R_c、R_dAnd R_e、R_eAnd R_f、R_fAnd R_g、R_gAnd R_hAnd R_hAnd R_iAt least one group selected from the group consisting of groups represented by the following formulae (A) to (H) in which at least one of the groups is bonded,

the amino, amido, imido and silyl groups may also have substituents L as defined in the formula (A-I),

L¹and L as defined in said formula (A-I)¹Are used in the same sense and have the same meaning,

L²represents a hydrogen atom or L as defined in said formula (A-I)^a～L^eAny one of the above-mentioned (A) and (B),

L³represents a hydrogen atom or said L^a～L^eAny one of the above-mentioned (A) and (B),

L⁴represents said L^a～L^eAny one of the above-mentioned (A) and (B),

Z_a～Z_dand Y_a～Y_dEach independently represents a hydrogen atom, a halogen atom, a hydroxyl group, a carboxyl group, a nitro group, an amino group, an amido group, an imido group, a cyano group, a silyl group or-L¹、-S-L²、-SS-L²、-SO₂-L³、-N＝N-L⁴(L¹～L⁴And said R_a～R_iL in (1)¹～L⁴Are the same meaning) or

An alicyclic hydrocarbon group of a 5-or 6-membered ring which may contain at least one of a nitrogen atom, an oxygen atom and a sulfur atom and is formed by bonding Z or Y to each other in two adjacent members,

an aromatic hydrocarbon group having 6 to 14 carbon atoms formed by bonding Z or Y to each other in two adjacent groups, or

And a C3-14 heteroaromatic hydrocarbon group containing at least one of a nitrogen atom, an oxygen atom and a sulfur atom, wherein Z or Y is bonded to each other in two adjacent groups, and the alicyclic hydrocarbon group, the aromatic hydrocarbon group and the heteroaromatic hydrocarbon group may have an aliphatic hydrocarbon group or a halogen atom having 1-9 carbon atoms.

[ solution 9]

In the formulae (A) to (H), R_xAnd R_yIn combination of R_bAnd R_c、R_dAnd R_e、R_eAnd R_f、R_fAnd R_g、R_gAnd R_hAnd R_hAnd R_iIn the combination of (a) and (b),

plural R_A～R_LEach independently represents a hydrogen atom, a halogen atom, a hydroxyl group, a carboxyl group, a nitro group, an amino group, an amido group, an imido group, a cyano group, a silyl group or-L¹、-S-L²、-SS-L²、-SO₂-L³or-N-L⁴(L¹～L⁴And L defined in the formulae (V-1) to (V-3)¹～L⁴Are the same meaning),the amino group, amide group, imide group and silane group may have the substituent L.

Examples of the squarylium salt-based coloring matter include compounds represented by the following formula (VI).

[ solution 10]

In the formula (VI), X independently represents an oxygen atom, a sulfur atom, a selenium atom, a tellurium atom or-NR⁸-，

R¹～R⁸Each independently represents a hydrogen atom, a halogen atom, a sulfo group, a hydroxyl group, a cyano group, a nitro group, a carboxyl group, a phosphoric acid group, -NR^gR^hRadical, -SO₂RⁱRadical, -OSO₂RⁱOr L shown below^a～L^hAny one of (1), R^gAnd R^hEach independently represents a hydrogen atom, -C (O) RⁱOr L shown below^a～L^eAny one of (1), RⁱRepresents the following L^a～L^eAny of the above.

(L^a) Aliphatic hydrocarbon group having 1 to 12 carbon atoms

(L^b) C1-C12 halogen-substituted alkyl group

(L^c) Alicyclic hydrocarbon group having 3 to 14 carbon atoms

(L^d) An aromatic hydrocarbon group having 6 to 14 carbon atoms

(L^e) A heterocyclic group having 3 to 14 carbon atoms

(L^f) C1-C12 alkoxy group

(L^g) An acyl group having 1 to 12 carbon atoms which may have a substituent L,

(L^h) Alkoxycarbonyl group having 1 to 12 carbon atoms and optionally having substituent L

The substituent L is at least one selected from the group consisting of an aliphatic hydrocarbon group having 1 to 12 carbon atoms, an alkyl group substituted with a halogen having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 14 carbon atoms, an aromatic hydrocarbon group having 6 to 14 carbon atoms, and a heterocyclic group having 3 to 14 carbon atoms.

The R is¹Preferably 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, or nitro group, and more preferably a hydrogen atom, chlorine atom, fluorine atom, methyl group, ethyl group, n-propyl group, isopropyl group, or hydroxyl group.

The R is²～R⁷Preferably, each independently represents a hydrogen atom, a chlorine atom, a fluorine atom, a methyl group, an ethyl group, a N-propyl group, an isopropyl group, a N-butyl group, a sec-butyl group, a tert-butyl group, a cyclohexyl group, a phenyl group, a hydroxyl group, an amino group, a dimethylamino group, a cyano group, a nitro group, an acetylamino group, a propionylamino group, a N-methylacetylamino group, a trifluoroformylamino group, a pentafluoroacetylamino group, a tert-butyrylamino group, a cyclohexanylamino group, or a N-butylsulfonyl group, and more preferably a hydrogen atom, a chlorine atom, a fluorine atom, a methyl group, an ethyl group, a N-propyl group, an isopropyl group, a tert-butyl group, a hydroxyl group, a dimethylamino group, a nitro group, an acetylamino.

The R is⁸Preferably a hydrogen atom, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, cyclohexyl group, or phenyl group, and more preferably a hydrogen atom, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, or tert-butyl group.

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

Compound (VI) can be represented by a method of describing a resonance structure as shown in the following formula (VI-2) in addition to the method of describing the following formula (VI-1). That is, the following formula (VI-1) differs from the following formula (VI-2) only in the description of the structure, and these all represent the same compound. In the present invention, unless otherwise specified, the structure of the squarylium salt compound is represented by the following description method (VI-1).

[ solution 11]

Further, for example, a compound represented by the following formula (VI-1) and a compound represented by the following formula (VI-3) can be considered to be the same compound.

[ solution 12]

The structure of the compound (VI) is not particularly limited as long as the compound (VI) satisfies the requirements of the formula (VI-1). The left and right substituents bonded to the central four-membered ring may be the same or different, and the same is preferable because synthesis is easy.

One compound (B) may be used alone, or two or more compounds may be used in combination. In addition, the content of the compound (B) is, for example, preferably 0.003 to 2.0 parts by weight, more preferably 0.0005 to 1.8 parts by weight, and particularly preferably 0.008 to 1.5 parts by weight, based on 100 parts by weight of the transparent resin, in the case of using, as the substrate (i), a substrate including a transparent resin substrate (ii) containing the compound (a) and the compound (B) or a substrate in which a resin layer such as an overcoat layer containing a curable resin or the like containing the compound (a) is laminated on a transparent resin substrate (iii) containing the compound (B). When a substrate in which a transparent resin layer such as a top coat layer containing a curable resin or the like containing the compound (a) and the compound (B) is laminated on a glass support or a resin support as a base or a substrate in which a resin layer such as a top coat layer containing a curable resin or the like containing the compound (B) is laminated on a transparent resin substrate (iv) containing the compound (a) is used as the substrate (i), the amount of the substrate is preferably 0.1 to 5.0 parts by weight, more preferably 0.2 to 4.0 parts by weight, and particularly preferably 0.3 to 3.0 parts by weight, based on 100 parts by weight of the resin forming the transparent resin layer containing the compound (a). When the content of the compound (B) is within the above range, a near infrared cut filter that combines good near infrared absorption characteristics with high visible light transmittance can be obtained.

< other pigment (X) >)

The base material (i) may further contain another coloring matter (X) which does not conform to the compound (a) and the compound (B).

The other coloring matter (X) is not particularly limited as long as the maximum absorption wavelength is less than 650nm or more than 850nm, and examples thereof include at least one compound selected from the group consisting of squarylium compounds, phthalocyanine compounds, cyanine compounds, naphthalocyanine compounds, ketanium compounds, octaporphyrin compounds, diimmonium compounds, perylene compounds, and metal dithiolate compounds. By using such another dye (X), a wider range of near-infrared light can be absorbed, and the transmittance in the near-infrared region is reduced.

< transparent resin >

The transparent resin layer and the transparent resin substrates (ii) to (iv) laminated on the resin support, the glass support, or the like can be formed using a transparent resin. The transparent resin used for the substrate (i) may be one kind alone, or two or more kinds thereof.

The transparent resin is not particularly limited as long as the effect of the present invention is not impaired, and for example, in order to ensure thermal stability and film formability and to produce a film capable of forming a dielectric multilayer film by high-temperature vapor deposition at a vapor deposition temperature of 100 ℃ or higher, a resin having a glass transition temperature (Tg) of preferably 110 to 380 ℃, more preferably 110 to 370 ℃, and still more preferably 120 to 360 ℃ may be mentioned. Further, it is particularly preferable that the glass transition temperature of the resin is 140 ℃ or higher because a film capable of forming a dielectric multilayer film by vapor deposition at a higher temperature can be obtained.

In the case of forming a resin plate having a thickness of 0.1mm including the resin, the transparent resin can be a resin having a total light transmittance (Japanese Industrial Standards (JIS) K7105) of the resin plate of preferably 75% to 95%, more preferably 78% to 95%, and particularly preferably 80% to 95%. When a resin having a total light transmittance in such a range is used, the obtained substrate exhibits excellent transparency as an optical film.

The transparent resin has a weight average molecular weight (Mw) of usually 15,000 to 350,000, preferably 30,000 to 250,000, and a number average molecular weight (Mn) of usually 10,000 to 150,000, preferably 20,000 to 100,000, in terms of polystyrene, as measured by Gel Permeation Chromatography (GPC).

Examples of the transparent resin include: a cyclic (poly) olefin-based resin, an aromatic polyether-based resin, a polyimide-based resin, a fluorene polycarbonate-based resin, a fluorene polyester-based resin, a polycarbonate-based resin, a polyamide (aramid) -based resin, a polyarylate-based resin, a polysulfone-based resin, a polyethersulfone-based resin, a polyphenylene-based resin, a polyamideimide-based resin, a Polyethylene Naphthalate (PEN) -based resin, a fluorinated aromatic polymer-based resin, a (modified) acrylic-based resin, an epoxy-based resin, an allyl-based curing resin, a silsesquioxane-based ultraviolet curing resin, an acrylic-based ultraviolet curing resin, and a vinyl-based ultraviolet curing resin.

Cyclic (poly) olefin resin

The cyclic (poly) olefin resin is preferably selected from the group consisting of the following formula (X)₀) A monomer represented by the formula (Y)₀) A resin obtained from at least one monomer of the group consisting of the monomers represented, and a resin obtained by hydrogenating the resin.

[ solution 13]

Formula (X)₀) In, R^x1～R^x4Each independently represents an atom or a group selected from the following (i ') to (ix'), k^x、m^xAnd p^xEach independently represents 0 or a positive integer.

(i') a hydrogen atom

(ii') a halogen atom

(iii') Trialkylsilyl group

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

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

(vi') a polar group (with the exception of (iv))

(vii')R^x1And R^x2Or R^x3And R^x4Alkylene groups formed by bonding to each other (wherein R not participating in the bonding is^x1～R^x4Each independently represents an atom or a group selected from the above (i ') to (vi'). )

(viii')R^x1And R^x2Or R^x3And R^x4A monocyclic or polycyclic hydrocarbon ring or heterocycle formed by bonding to each other (wherein R not participating in the bonding is^x1～R^x4Each independently represents an atom or a group selected from the above (i ') to (vi'). )

(ix')R^x2And R^x3A monocyclic hydrocarbon ring or heterocyclic ring which is bonded to each other to form a monocyclic ring (wherein R which does not participate in the bonding is present)^x1And R^x4Each independently represents an atom or a group selected from the above (i ') to (vi'). )

[ solution 14]

Formula (Y)₀) In, R^y1And R^y2Each independently represents an atom or a group selected from the above-mentioned groups (i ') to (vi'), or R^y1And R^y2A monocyclic or polycyclic alicyclic, aromatic or heterocyclic ring formed by bonding to each other, k^yAnd p^yEach independently represents 0 or a positive integer.

Aromatic polyether resin

The aromatic polyether 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).

[ solution 15]

In the formula (1), R¹～R⁴Each independently represents a monovalent organic group having 1 to 12 carbon atoms, and a to d each independently represents an integer of 0 to 4.

[ solution 16]

In the formula (2), R¹～R⁴And a to d are each independently of R in the formula (1)¹～R⁴And a to d are the same, Y represents a single bond, -SO₂-or > C ═ O, R⁷And R⁸Each independently represents a halogen atom, a monovalent organic group having 1 to 12 carbon atoms or a nitro group, g and h each independently represent an integer of 0 to 4, and m represents 0 or 1. Wherein, when m is 0, R⁷Is not cyano.

The aromatic polyether resin preferably further contains 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).

[ solution 17]

In the formula (3), R⁵And R⁶Each independently represents a C1-12 monovalent organic group, and Z represents a single bond, -O-, -S-, -SO₂-, > C ═ O, -CONH-, -COO-, or a divalent organic group having 1 to 12 carbon atoms, e and f each independently represent an integer of 0 to 4, and n represents 0 or 1.

[ solution 18]

In the formula (4), R⁷、R⁸Y, m, g and h are each independently of R in the formula (2)⁷、R⁸Y, m, g and h are the same, R⁵、R⁶Z, n, e and f are each independently R in the formula (3)⁵、R⁶Z, n, e and f are the same.

Polyimide-based resin

The polyimide-based resin is not particularly limited as long as it is a polymer compound having an imide bond in a repeating unit, and can be synthesized, for example, by the method described in Japanese patent laid-open Nos. 2006-199945 and 2008-163107.

Fluorene polycarbonate-based resin

The fluorene polycarbonate-based resin is not particularly limited as long as it is a polycarbonate resin containing a fluorene moiety, and can be synthesized, for example, by the method described in japanese patent application laid-open No. 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, and can be synthesized, for example, by the methods described in japanese patent application laid-open No. 2010-285505 or japanese patent laid-open No. 2011-197450.

Fluorinated aromatic polymer-based resin

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

Acrylic ultraviolet-curing resin

The acrylic ultraviolet-curable resin is not particularly limited, and examples thereof include: the resin composition is synthesized from a resin composition containing a compound having one or more acrylic groups or methacrylic groups in a molecule and a compound which is decomposed by ultraviolet rays to generate active radicals. When a substrate in which a transparent resin layer containing a compound (B) and a curable resin is laminated on a glass support or a resin support as a base, or a substrate in which a resin layer containing a curable resin or the like is laminated on a transparent resin substrate (ii) containing a compound (B) is used as the substrate (i), an acrylic ultraviolet curable resin is particularly preferably used as the curable resin.

(commercially available products)

As a commercially available product of the transparent resin, the following commercially available products can be mentioned. Examples of commercially available products of the cyclic (poly) olefin resin include: atton (Arton) manufactured by Japan Synthetic Rubber (JSR) (stock), renoor (Zeonor) manufactured by nippon (Zeon) (stock), Apler (APEL) manufactured by mitsui chemical (stock), TOPAS (TOPAS) manufactured by polyplasics (stock), and the like. Commercially available products of polyethersulfone resin include smikaikecel (Sumikaexcel) PES manufactured by sumitomo chemical (stock). Examples of commercially available polyimide resins include Nippopim (Neopulim) L manufactured by Mitsubishi gas chemical (Strand). As a commercially available product of the polycarbonate-based resin, there can be mentioned Pures (PURE-ACE) manufactured by Dichen (R). As a commercial product of the fluorene polycarbonate-based resin, there can be mentioned Eupatorium (Ifpita) EP-5000 manufactured by Mitsubishi gas chemical (Strand). Examples of commercially available fluorene polyester resins include OKP4HT manufactured by Osaka gas chemistry (Osaka gas chemicals) (incorporated by reference). Examples of commercially available acrylic resins include akulivera (Acryviewa) manufactured by japan catalyst (japan). Commercially available products of silsesquioxane-based ultraviolet curable resins include hillaplace (Silplus) manufactured by sienna chemical corporation.

< other ingredients >

The substrate (i) may further contain additives such as an antioxidant, a near-ultraviolet absorber, a fluorescence-quenching agent, and a metal complex compound, within a range not impairing the effects of the present invention. 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, triazine compounds, and the like.

Examples of the antioxidant include: 2, 6-di-tert-butyl-4-methylphenol, 2' -dioxo-3, 3' -di-tert-butyl-5, 5' -dimethyldiphenylmethane, tetrakis [ methylene-3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate ] methane, and the like.

These additives may be mixed with the resin or the like at the time of producing the base material (i), or may be added at the time of synthesizing the resin. The amount of the additive is appropriately selected depending on 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.

< method for producing substrate (i) >

When the base material (i) is a base material including the transparent resin substrate (ii) to the transparent resin substrate (iv), the transparent resin substrate (ii) to the transparent resin substrate (iv) may be formed by, for example, melt molding or cast molding, and if necessary, a coating agent such as an antireflective agent, a hard coat agent, and/or an antistatic agent may be applied after molding, thereby producing a base material on which an overcoat layer is laminated.

When the substrate (i) is a substrate in which a transparent resin layer such as an overcoat layer containing a curable resin containing the compound (a) and the compound (B) is laminated on a glass support or a resin support serving as a base, for example, a resin solution containing the compound (a) and the compound (B) is melt-molded or cast-molded on the glass support or the resin support serving as a base, and preferably, the substrate is coated by a method such as spin coating, slit coating, or ink jet, then the solvent is dried and removed, and if necessary, light irradiation or heating is further performed, whereby a substrate in which a transparent resin layer is formed on a glass support or a resin support serving as a base can be produced.

Melt forming

Specific examples of the melt molding include: a method of melt-molding pellets obtained by melt-kneading a resin with the compound (a), the compound (B), and the like; a method of melt-molding a resin composition containing a resin, a compound (A) and a compound (B); or a method of melt-molding pellets obtained by removing the solvent from a resin composition containing the compound (a), the compound (B), the resin, and the solvent. Examples of the melt molding method include: injection molding, melt extrusion molding, blow molding, or the like.

Casting and Forming

The cast molding may be produced by the following method or the like: a method of casting a resin composition comprising the compound (a), the compound (B), a resin and a solvent onto a suitable support and removing the solvent; or a method in which a curable composition containing the compound (a), the compound (B), a photocurable resin and/or a thermosetting resin is cast on a suitable support, the solvent is removed, and then the composition is cured by a suitable method such as ultraviolet irradiation or heating.

In the case where the substrate (i) is a substrate including a transparent resin substrate (ii) containing the compound (a) and the compound (B), the substrate (i) can be obtained by peeling off the coating film from a support after casting molding, and in the case where the substrate (i) is a substrate in which a transparent resin layer including a top coat layer or the like of a curable resin or the like containing the compound (a) and the compound (B) is laminated on a support such as a glass support or a resin support as a base, the substrate (i) can be obtained by not peeling off the coating film after casting molding.

Examples of the support include: glass plates, steel belts, steel drums, and supports made of transparent resin (e.g., polyester film, cycloolefin resin film).

Further, the transparent resin layer may be formed on the optical component by: a method of drying a solvent by applying the resin composition to an optical component made of a glass plate, quartz, or transparent plastic; or a method of applying the curable composition, curing the composition, and drying the composition.

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

[ dielectric multilayer film ]

The near-infrared cut filter of the present invention has a dielectric multilayer film on at least one surface of the substrate (i). The dielectric multilayer film of the present invention is a film having a capability of reflecting near infrared rays. In the present invention, the near infrared ray reflective film may be provided on one surface or both surfaces of the substrate (i). When the filter is provided on one surface, the filter is excellent in manufacturing cost and ease of manufacturing, and when the filter is provided on both surfaces, the near infrared cut filter has high strength and is less likely to warp or twist. When the near-infrared cut filter is applied to the solid-state imaging device, the warp or twist of the near-infrared cut filter is preferably small, and therefore, the dielectric multilayer film is preferably provided on both surfaces of the substrate (i).

The dielectric multilayer film preferably has a reflection characteristic over the entire wavelength range of 700nm to 1100nm, more preferably over the entire wavelength range of 700nm to 1150nm, and particularly preferably over the entire wavelength range of 700nm to 1200 nm. Examples of the form having the dielectric multilayer film on both surfaces of the substrate (i) include: a first optical layer having reflection characteristics mainly at a wavelength of about 700nm to 1150nm when measured at an angle of 30 DEG with respect to a vertical direction of a near infrared ray cut filter on one surface of a substrate (i) having a glass support, and a second optical layer having antireflection properties in the visible region is provided on the other surface (see FIG. 3(a)), or a third optical layer having reflection characteristics mainly at a wavelength of about 700nm to 950nm when measured from an angle of 30 DEG with respect to the perpendicular direction of the near infrared ray cut filter on one surface of the substrate (i), and a fourth optical layer having reflection characteristics mainly in the vicinity of 900nm to 1150nm when measured from an angle of 30 DEG with respect to the perpendicular direction of the near infrared ray cut filter on the other surface of the substrate (i) (see FIG. 3 (b)).

The near infrared ray cut filter of the present invention is preferably such that the substrate (i) has a glass support and includes dielectric multilayer films on both surfaces of the substrate (i), more preferably such dielectric multilayer films are a near infrared ray reflective film and a visible light antireflection film, and particularly preferably such dielectric multilayer films have a near infrared ray reflective film on one surface of the substrate (i) and a visible light antireflection film on the other surface.

The dielectric multilayer film may be a dielectric multilayer film in which high refractive index material layers and low refractive index material layers are alternately stacked. As the 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 a material include a material containing titanium oxide, zirconium oxide, tantalum pentoxide, niobium pentoxide, lanthanum oxide, yttrium oxide, zinc sulfide, indium oxide, or the like as a main component, and a small amount (for example, 0 to 10% by weight based on the main component) of titanium oxide, tin oxide, cerium oxide, or the like.

As the 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: silicon dioxide, aluminum oxide, lanthanum fluoride, magnesium fluoride and sodium aluminum hexafluoride.

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 dielectric multilayer film in which high refractive index material layers and low refractive index material layers are alternately stacked can be directly formed on the substrate (i) by a Chemical Vapor Deposition (CVD) method, a sputtering method, a vacuum deposition method, an ion-assisted deposition method, an ion plating method, or the like.

In general, if the wavelength of the near infrared ray to be blocked is λ (nm), the thickness of each of the high refractive index material layer and the low refractive index material layer is preferably 0.1 λ to 0.5 λ. The value of λ (nm) is, for example, 700nm to 1400nm, preferably 750nm to 1300 nm. When the thickness is in the above range, the optical film thickness calculated from λ/4 as the product (n × d) of the refractive index (n) and the film thickness (d) and the thickness of each of the high refractive index material layer and the low refractive index material layer become substantially the same value, and the blocking/transmission of a specific wavelength tends to be easily controlled in accordance with the relationship between the optical characteristics of reflection and refraction.

The number of layers of the dielectric multilayer film, which are stacked together of the high refractive index material layer and the low refractive index material layer, is preferably 16 to 70 layers, and more preferably 20 to 60 layers, based on the entire near infrared ray cut filter. When the thickness of each layer, the thickness of the dielectric multilayer film as a whole near infrared ray cut filter, or the total number of layers falls within the above range, it is possible to secure a sufficient manufacturing margin and reduce warpage of the near infrared ray cut filter or cracks in the dielectric multilayer film.

In the present invention, by appropriately selecting the types of materials constituting the high refractive index material layer and the low refractive index material layer, the thicknesses of the respective layers of the high refractive index material layer and the low refractive index material layer, the order of lamination, and the number of lamination in combination with the absorption characteristics of the compound (a) or the compound (B), it is possible to ensure a sufficient transmittance in the visible region, have a sufficient light-cut characteristic in the near infrared wavelength region, and reduce the reflectance when near infrared rays enter from an oblique direction.

In order to optimize the conditions, for example, optical Film design software (e.g., manufactured by core metal machine, Thin Film Center) may be used to set parameters so that the antireflection effect in the visible region and the light-blocking effect in the near-infrared region can be compatible with each other. In the case of the software, for example, there may be mentioned: in designing the first optical layer, a parameter setting method is used, for example, in which the Target transmittance at a wavelength of 400 to 700nm is set to 100%, the Target Tolerance (Target Tolerance) value is set to 1, the Target transmittance at a wavelength of 705 to 950nm is set to 0%, and the Target Tolerance value is set to 0.5. These parameters may also be used to change the value of the target tolerance by dividing the wavelength range more finely in conjunction with various characteristics of the substrate (i) and the like.

[ other functional films ]

In the near-infrared cut filter of the present invention, a functional film such as an antireflection film, a hard coat film or an antistatic film may be appropriately provided between the substrate (i) and the dielectric multilayer film, on the surface of the substrate (i) opposite to the surface on which the dielectric multilayer film is provided, or on the surface of the dielectric multilayer film opposite to the surface on which the substrate (i) is provided, for the purpose of improving the surface hardness of the substrate (i) or the dielectric multilayer film, improving chemical resistance, antistatic properties, removing damage, and the like, within a range in which the effects of the present invention are not impaired.

The near infrared ray cut filter of the present invention may include one layer containing the functional film, or may include two or more layers. When the near-infrared cut filter of the present invention includes two or more layers including the functional film, the near-infrared cut filter may include two or more layers that are the same or may include two or more different layers.

The method of laminating the functional film is not particularly limited, and examples thereof include: and (ii) a method of melt-molding or cast-molding a coating agent such as an antireflective agent, a hard coat agent and/or an antistatic agent on the substrate (i) or the dielectric multilayer film in the same manner as described above.

In addition, the method can also be manufactured by the following steps: the curable composition containing the coating agent or the like is applied to the substrate (i) or the dielectric multilayer film by a bar coater or the like, and then cured by ultraviolet irradiation or the like.

Examples of the coating agent include: ultraviolet (UV)/Electron Beam (Electron Beam, EB) curable resins or thermosetting resins, and specific examples thereof include: vinyl compounds, urethane, acrylic ester, epoxy and epoxy acrylate resins, and the like. The curable composition containing these coating agents includes: and curable compositions of vinyl, urethane, acrylic urethane, acrylate, epoxy, and epoxy acrylate.

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

In the curable composition, the proportion of the polymerization initiator is preferably 0.1 to 10% by weight, more preferably 0.5 to 10% by weight, and still more preferably 1 to 5% by weight, based on 100% by weight of the total amount of the curable composition. When the blending ratio of the polymerization initiator is in the above range, a functional film such as an antireflection film, a hard coat film or an antistatic film having excellent curing characteristics and workability of the curable composition and having a desired hardness can be obtained.

Further, an organic solvent may be added to the curable composition as a solvent, and a known organic solvent may be used as the organic solvent. Specific examples of the organic solvent include: alcohols such as methanol, ethanol, isopropanol, butanol, and octanol; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; esters such as ethyl acetate, butyl acetate, ethyl lactate, γ -butyrolactone, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, and the like; ethers such as ethylene glycol monomethyl ether and diethylene glycol monobutyl ether; aromatic hydrocarbons such as benzene, toluene, and xylene; amides such as dimethylformamide, dimethylacetamide and N-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 substrate (i) and the functional film and/or the dielectric multilayer film, or the adhesion between the functional film and the dielectric multilayer film, the surface of the substrate (i), the functional film, or the dielectric multilayer film may be subjected to surface treatment such as corona treatment or plasma treatment.

[ method for producing near-infrared cut-off Filter ]

The method for manufacturing a near-infrared cut filter according to the present invention is characterized in that: comprises a step of forming a dielectric multilayer film on at least one surface of the substrate (i). The method of forming the dielectric multilayer film is as described above. In addition, a step of forming a functional film on the substrate (i) may also be included as necessary.

In addition, when the near-infrared cut filter is warped when the dielectric multilayer film is formed, the following method or the like can be adopted in order to solve the above problem: a dielectric multilayer film is formed on both surfaces of the near infrared cut filter, or an electromagnetic wave such as ultraviolet light is irradiated to the surface of the near infrared cut filter on which the dielectric multilayer film is formed. In the case of irradiation with electromagnetic waves, irradiation may be performed during the formation of the dielectric multilayer film, or may be performed separately after the formation.

[ use of near-infrared cut-off Filter ]

The near infrared ray cut filter of the present invention has a wide viewing angle, and has excellent near infrared ray cut capability and the like. Therefore, the present invention is effectively used for the purpose of correcting the visual sensitivity of a solid-state imaging device such as a CCD image sensor or a CMOS image sensor of a camera module. In particular, the present invention is effectively used in digital still cameras, cameras for smartphones, cameras for mobile phones, digital video cameras, cameras for wearable devices, Personal Computer (PC) cameras, surveillance cameras, cameras for automobiles, televisions, car navigation systems, portable information terminals, video game machines, portable game machines, fingerprint authentication systems, digital music players, and the like. Further, the infrared cut filter is also effectively used as an infrared cut filter mounted on a glass plate or the like of an automobile, a building or the like.

[ solid-state imaging device ]

The solid-state imaging device of the present invention includes the near-infrared cut filter of the present invention. Here, the solid-state imaging device is an image sensor including a solid-state imaging element such as a CCD image sensor or a CMOS image sensor, and is particularly useful for applications such as a digital still camera, a camera for a smartphone, a camera for a mobile phone, a camera for a wearable device, and a digital video camera. For example, the camera module of the present invention includes the near infrared ray cut filter of the present invention.