JP7293875B2 - Optical filters and optical sensor devices - Google Patents

Description

The present invention relates to optical filters and optical sensor devices. More specifically, the present invention relates to an optical filter that cuts visible light and selectively transmits near-infrared rays of two or more different wavelength bands, and an optical sensor device using the optical filter.

In recent years, various optical sensor devices using near-infrared rays have been developed for use in mobile information terminal devices such as smartphones, tablet terminals, and wearable devices. Optical sensor devices are being considered for various applications in information terminal devices. Examples include space recognition applications such as distance measurement, motion recognition applications, and security applications such as iris authentication, vein authentication in the white of the eye, and face authentication. , and healthcare applications such as pulse measurement and blood oxygen concentration measurement.

In an optical sensor device using near-infrared rays, it is important to cut unnecessary wavelengths of light, especially visible light, in order for the sensing function to work accurately. Also, depending on the wavelength of the near-infrared rays used for sensing, near-infrared rays with shorter wavelengths are cut (for example, when near-infrared rays around 800 nm are used for sensing, near-infrared rays up to around 740 nm are cut in addition to visible rays. By doing so, noise during use can be reduced, and the characteristics of the optical sensor device can be improved. In addition, by using near-infrared rays of two or more different wavelength bands for sensing, it is possible to acquire more information at the same time than sensors that use near-infrared rays of one wavelength band, resulting in more precise and less noise sensing performance. can be achieved. Furthermore, when using the sensor for security purposes, multiple types of authentication (for example, iris authentication and face authentication) can be performed at the same time, speeding up authentication and reducing power consumption of the device. In such applications, it is possible to further improve sensing performance by cutting near-infrared rays outside the wavelength band used for sensing.

As a means for cutting visible light and transmitting near-infrared rays of a specific wavelength, a bandpass filter is disclosed in which a high refractive index material and a low refractive index material are alternately laminated on a glass substrate (see, for example, Patent Document 1). ). However, an optical filter formed with such a multilayer thin film has optical characteristics that vary greatly depending on the incident angle of incident light. Therefore, when it is used for mobile information terminal devices, there is a problem that the detection accuracy of the optical sensor is lowered.

On the other hand, as optical filters capable of cutting visible light regardless of the angle of incidence, glass filters having metallic coloring components (see, for example, Patent Document 2) and filters containing colored pigments (see, for example, Patent Document 3) are known. there is All of these cut visible light by absorption, and the change in optical characteristics due to the angle of incidence is small. In some cases, it cannot be suitably used for mobile information terminals that are becoming lighter in weight.

In addition, when these filters are made thinner, there is a problem that the light-cutting performance due to absorption is greatly reduced, resulting in an increase in noise during sensing. Furthermore, when the wavelength of the near-infrared rays used for sensing is 800 nm or more (currently, such wavelengths are the mainstream from the viewpoint of invisibility), these filters have insufficient near-infrared cut characteristics with shorter wavelengths. In addition, the slope of the absorption spectrum is gentle, especially in optical filters containing colored pigments, and the contrast between light cut and light transmission tends to be low (increase in noise during sensing).

As an infrared light transmission filter capable of achieving both thinness and reduced incidence angle dependence, an infrared light transmission filter having a film containing a near-infrared absorbing agent on a base material containing a visible light absorbing agent has been proposed. (See Patent Documents 4 and 5, for example). However, they either have a single near-infrared transmission band or transmit all near-infrared rays after a certain wavelength, and do not have the function of selectively transmitting near-infrared rays in two or more different wavelength bands. In order to achieve the high level of sensing performance demanded in recent years, it has been desired to develop an optical filter that efficiently blocks visible light and has two or more different transmission bands in the near-infrared region.

JP 2015-184627 A JP-A-07-126036 JP-A-60-139757 Japanese Patent No. 5741283 WO2017/213047

The present invention has an excellent cut property against visible light even when the incident angle is increased as the height of the equipment in which the optical sensor device is installed is reduced, and at the same time, two or more different transmission bands are provided in the near-infrared region. An object is to provide an optical filter having

[1] It has a resin layer containing a compound (Z) having an absorption maximum in the wavelength region of 700 to 1000 nm, and a dielectric multilayer film, and has two or more different transmission bands in the near-infrared region, and , an optical filter that blocks visible light.
[2] The optical filter according to item [1], which further satisfies the following requirements (a) and (b):
(a) In the wavelength region of 380 to 700 nm, the average value of transmittance when measured from the direction perpendicular to the surface direction of the optical filter is 5% or less;
(b) having a light blocking band (Za), a light transmitting band (Zb), a light blocking band (Zc), a light transmitting band (Zd) and a light blocking band (Ze) in a wavelength range of 700 to 1200 nm, respectively; The center wavelength of the band is Za<Zb<Zc<Zd<Ze.
[3] The optical filter according to item [1] or [2], which further satisfies the following requirement (c):
(c) In the light transmission band (Zb), Xa (nm) is the wavelength on the shortest wavelength side at which the transmittance when measured from the direction perpendicular to the surface of the optical filter is 15%. When the value of the wavelength on the longer wavelength side is Xb (nm), the value of Y1 represented by Y1=(Xa+Xb)/2 is 750 to 950 nm.
[4] The optical filter according to any one of items [1] to [3], further satisfying the following requirement (d):
(d) In the light transmission band (Zd), Xc (nm) is the value of the wavelength on the shortest wavelength side at which the transmittance when measured from the direction perpendicular to the surface of the optical filter is 20%. When the value of the wavelength on the long wavelength side is Xd (nm), the value of Y2 represented by Y2=(Xc+Xd)/2 is 900 to 1200 nm.
[5] The compound (Z) is selected from the group consisting of squarylium-based compounds, phthalocyanine-based compounds, naphthalocyanine-based compounds, croconium-based compounds, pyrrolopyrrole-based compounds, hexaphylline-based compounds, cyanine-based compounds, and boron dipyrromethene-based compounds. The optical filter according to any one of items [1] to [4], which is at least one selected compound.
[6] The optical filter according to any one of items [1] to [5], wherein the compound (Z) contains two or more compounds having different maximum absorption wavelengths.
[7] The compound (Z) comprises one or more compounds (Z1) having an absorption maximum in the wavelength range of 700 to 850 nm and one or more compounds (Z2) having an absorption maximum in the wavelength range of 851 to 1000 nm. The optical filter according to any one of items [1] to [5], comprising:
[8] The difference between the maximum absorption wavelength of the compound (Z1) on the long wavelength side and the maximum absorption wavelength of the compound (Z2) on the short wavelength side is 80. The optical filter according to item [7], which is ~240 nm.
[9] The optical filter according to any one of items [1] to [8], further containing a compound (S) having an absorption maximum in the wavelength range of 350 to 699 nm.
[10] The resin constituting the 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, a poly Arylate resin, polysulfone resin, polyethersulfone resin, polyparaphenylene resin, polyamideimide resin, polyethylene naphthalate resin, fluorinated aromatic polymer resin, (modified) acrylic resin, epoxy resin , at least one resin selected from the group consisting of allyl ester curable resins, silsesquioxane ultraviolet curable resins, acrylic ultraviolet curable resins and vinyl ultraviolet curable resins, [1] to The optical filter according to any one of [9].
[11] The optical filter according to any one of items [1] to [10], which is for an optical sensor device.
[12] An optical sensor device comprising the optical filter according to any one of items [1] to [11].

The optical filter of the present invention has excellent cut properties against visible light, has two or more different transmission bands in the near-infrared region, and has little change in optical properties even when light is incident from an oblique direction. , is suitable for optical sensor applications that require a high level of sensing performance.

It is a figure explaining the example of the aspect of the optical filter of this invention. FIG. 4 is a diagram illustrating an example of a base material that constitutes the optical filter of the present invention. An embodiment of measuring the transmission spectrum (A) transmittance when measured from the vertical direction of the optical filter and (B) transmittance when measured at an angle of 30° with respect to the vertical direction of the optical filter will be described. It is a diagram. 4 is a graph showing the spectral transmittance of the base material produced in Example 1. FIG. 4 is a graph showing the spectral transmittance of the optical filter produced in Example 1. FIG. 4 is a graph showing the spectral transmittance of the base material produced in Example 2. FIG. 4 is a graph showing the spectral transmittance of the optical filter produced in Example 2. FIG. 10 is a graph showing the spectral transmittance of the optical filter produced in Example 4. FIG. 10 is a graph showing the spectral transmittance of the base material produced in Example 6. FIG. 10 is a graph showing the spectral transmittance of the optical filter produced in Example 6. FIG. 4 is a graph showing the spectral transmittance of the optical filter produced in Comparative Example 1. FIG. 7 is a graph showing the spectral transmittance of the optical filter produced in Comparative Example 2. FIG.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of an optical filter according to the present invention will be described with reference to the drawings. However, the present invention can be implemented in many different aspects and should not be construed as being limited to the description of the embodiments exemplified below. In order to make the description clearer, the drawings may schematically show the width, thickness, shape, etc. of each part compared to the actual embodiment, but this is only an example and limits the interpretation of the present invention. not a thing In addition, in this specification and each figure, the same reference numerals or similar reference numerals (a, b, etc. are simply added after the number) are attached to the same elements as those described above with respect to the previous figures. and detailed description may be omitted as appropriate.

In this specification, the term "upper" refers to a relative position with respect to the main surface of the supporting substrate (the surface on which the solid-state imaging device is arranged), and the direction away from the main surface of the supporting substrate is "upper". . In this drawing, "top" is the upper side toward the paper surface. "Above" includes the case of being in contact with the object (that is, the case of "on") and the case of being located above the object (that is, the case of "over"). Conversely, "lower" refers to a relative position with respect to the main surface of the supporting substrate, and the direction toward the main surface of the supporting substrate is "lower". In this drawing, the downward direction toward the paper surface is "bottom".

[Optical filter]
The optical filter according to the present invention has a resin layer containing a compound (Z) having an absorption maximum in the wavelength range of 700 to 1000 nm and a dielectric multilayer film, and has two or more different transmission bands in the near infrared region. and blocking visible light.

The term “absorption maximum” used herein means the absorption maximum of a compound on the longest wavelength side within the wavelength range of 300 to 1500 nm. That is, in the case of a compound having a plurality of absorption maxima within the above wavelength region, it refers to the absorption maxima on the longest wavelength side.

The near-infrared region is preferably 700-1500 nm, more preferably 720-1400 nm, particularly preferably 750-1200 nm. By having two or more different transmission bands in the near-infrared region, it is possible to achieve particularly excellent sensing performance, facilitate the design of the dielectric multilayer film, and reduce manufacturing costs.

The optical filter of the present invention preferably satisfies the following requirements (a) and (b).
Requirement (a) : In the wavelength range of 380 to 700 nm, the average transmittance measured in the direction perpendicular to the surface of the optical filter is 5% or less.
The average transmittance is preferably 4% or less, more preferably 3% or less, still more preferably 2% or less, and particularly preferably 1% or less. When the average value of the transmittance is within this range, visible light unnecessary for near-infrared sensing can be efficiently cut, and excellent sensing performance with little noise can be achieved.

Requirement (b) : Has a light blocking band (Za), light transmission band (Zb), light blocking band (Zc), light transmission band (Zd) and light blocking band (Ze) in the wavelength region of 700 to 1200 nm. , the center wavelengths of the respective bands are Za<Zb<Zc<Zd<Ze.

<Light transmission zone>
The light transmission bands (Zb) and (Zd) are wavelength bands in which the transmittance measured from the direction perpendicular to the surface of the optical filter is 15% or more in the wavelength region of 700 to 1200 nm, and the width thereof refers to a wavelength band of 5 nm or more.

The width of the light transmission band (Zb) is preferably 7 nm or more, more preferably 10 nm or more, and particularly preferably 15 nm or more. Although the upper limit of the width is not particularly limited, it is preferably 100 nm or less from the viewpoint of ease of optical design. The average transmittance T(Zb) in the light transmission band (Zb) is preferably 18% or more, more preferably 20% or more, and particularly preferably 22% or more.

The width of the light transmission band (Zd) is preferably 10 nm or more, more preferably 20 nm or more, and particularly preferably 30 nm or more. Although the upper limit of the width is not particularly limited, it is preferably 130 nm or less from the viewpoint of ease of optical design. The average transmittance T (Zd) in the light transmission zone (Zd) is preferably 20% or higher, more preferably 25% or higher, still more preferably 30% or higher, and particularly preferably 35% or higher.

<Light blocking zone>
The light blocking bands (Za), (Zc) and (Ze) are wavelength bands in which the transmittance measured from the direction perpendicular to the surface of the optical filter is 5% or less in the wavelength region of 700 to 1200 nm, In addition, it refers to a wavelength band whose width is 5 nm or more.

The width of the light blocking band (Za) is preferably 10 nm or more, more preferably 15 nm or more, and particularly preferably 20 nm or more. Although the upper limit of the width is not particularly limited, it is preferably 130 nm or less from the viewpoint of ease of optical design. Even if the wavelength band with a transmittance of 5% or less in the light blocking band (Za) is continuous from the region with a wavelength of 700 nm or more to the region with a wavelength of less than 700 nm, the light blocking band (Za) has a lower limit of 700 nm. do. The average transmittance T(Za) in the light blocking zone (Za) is preferably 4% or less, more preferably 3% or less, particularly preferably 2% or less.

The width of the light blocking band (Zc) is preferably 7 nm or more, more preferably 10 nm or more, and particularly preferably 15 nm or more. Although the upper limit of the width is not particularly limited, it is preferably 100 nm or less from the viewpoint of ease of optical design. The average transmittance T(Zc) in the light blocking band (Zc) is preferably 4% or less, more preferably 3% or less, particularly preferably 2% or less.

The width of the light blocking band (Ze) is preferably 20 nm or more, more preferably 50 nm or more, even more preferably 80 nm or more, and particularly preferably 100 nm or more. Although the upper limit of the width is not particularly limited, it is preferably 200 nm or less from the viewpoint of ease of optical design. Even if the wavelength band with a transmittance of 5% or less in the light stop band (Ze) is continuous from the region with a wavelength of 1200 nm or less to the region with a wavelength of more than 1200 nm, the light stop band (Ze) has an upper limit of 1200 nm. do. The average transmittance T(Ze) in the light blocking band (Ze) is preferably 4% or less, more preferably 2% or less, particularly preferably 1% or less.

When the width and average transmittance of the light blocking zone (Za), light transmission zone (Zb), light blocking zone (Zc), light transmission zone (Zd), and light blocking zone (Ze) are as described above, they are used for sensing. It is preferable because only near-infrared rays can be efficiently transmitted, and good sensing performance with little noise can be achieved.

Preferably, the optical filter of the present invention further satisfies the following requirement (c).
Requirement (c) ; In the light transmission band (Zb), Xa (nm) is the value of the wavelength on the shortest wavelength side at which the transmittance when measured from the direction perpendicular to the surface of the optical filter is 15%. , where the value of the wavelength on the longest wavelength side is Xb (nm), the value of Y1 (the center wavelength of the light transmission band (Zb)) expressed by Y1=(Xa+Xb)/2 is 750 to 950 nm.

The value of Y1 is preferably 760-930 nm, more preferably 770-910 nm, particularly preferably 780-890 nm. When the value of Y1 is within the above range, it is possible to perform sensing with less noise, and a relatively inexpensive near-infrared light source (near-infrared LED, etc.) can be applied, which is preferable.

Preferably, the optical filter of the present invention further satisfies the following requirement (d).
Requirement (d) : In the light transmission band (Zd), Xc (nm) is the value of the wavelength on the shortest wavelength side at which the transmittance when measured from the direction perpendicular to the surface of the optical filter is 20%. , where the value of the wavelength on the longest wavelength side is Xd (nm), the value of Y2 (the center wavelength of the light transmission band (Zd)) expressed by Y2=(Xc+Xd)/2 is 900 to 1200 nm.

The value of Y2 is preferably 910-1150 nm, more preferably 920-1100 nm, particularly preferably 930-1050 nm. When the value of Y2 is within the above range, sensing with less noise becomes possible, and a relatively inexpensive near-infrared light source (near-infrared LED, etc.) can be applied, which is preferable.

Preferably, the optical filter of the present invention further satisfies the following requirement (e).
Requirement (e) ; Xa' is the value of the wavelength on the shortest wavelength side at which the transmittance when measured at an angle of 30° from the direction perpendicular to the surface of the optical filter is 15% in the light transmission band (Zb). (nm), and the value of the wavelength on the longest wavelength side is Xb′ (nm), the absolute value of the difference between Xa′ and Xa in the above requirement (c) |Xa−Xa′| and Xb′ and the absolute value |Xb−Xb′| of the difference between Xb in the requirement (c) and Xb in the requirement (c) are both 15 nm or less. Both of the absolute values |Xa-Xa'| and |Xb-Xb'| are preferably 12 nm or less, more preferably 10 nm or less. When these absolute values are within the above range, the difference in the spectral characteristics of the light transmission band (Zb) depending on the angle becomes limited, and noise reduction during sensing can be achieved, which is preferable.

The optical filter of the present invention has a resin layer containing the compound (Z) and a dielectric multilayer film, has two or more different transmission bands in the near-infrared region, and blocks visible light. The structure is not particularly limited as long as it has the properties. and a dielectric multilayer film. Hereinafter, examples of embodiments of the optical filter of the present invention will be described with reference to FIGS. 1(A) to 1(D).

An optical filter 100a shown in FIG. 1A has a dielectric multilayer film 104 on at least one surface of a substrate (i) . The dielectric multilayer film 104 is a wavelength-selective reflective film having properties of reflecting visible light and part of near-infrared light, and light transmission bands (Zb) and (Zd), depending on the optical properties of the substrate (i). It can be appropriately selected from an anti-reflection film that suppresses light reflection and a near-infrared reflective film that reflects near-infrared rays on the longer wavelength side than the light transmission band (Zd). For example, if the substrate (i) has sufficient visible light cut performance, there may be no problem in use without using a dielectric multilayer film that reflects the visible light region (having a mirror-like appearance). In some cases, a dielectric multilayer film that suppresses light reflection in the visible light region is preferred in terms of design (the black appearance can be maintained). Also, FIG. 1B shows an optical filter 100b having dielectric multilayer films 104 on both sides of a substrate (i) 102. FIG. Thus, the dielectric multilayer film may be provided on one side or both sides of the substrate (i). When provided on one side, it is excellent in manufacturing cost and ease of manufacture, and when provided on both sides, it is possible to obtain an optical filter that has high strength and is less likely to warp or twist. When the optical filter is applied to an optical sensor device, it is preferable that the optical filter has less warping and twisting.

It is preferable that the dielectric multilayer film 104 has a reflection characteristic with respect to light in a wavelength region longer than the light transmission band (Zd) among light incident at an angle of 5° with respect to the vertical direction. . For example, when the center wavelength Y2 of the light transmission band (Zd) is around 950 nm, it is particularly preferable to have reflection characteristics around 1050 to 1200 nm.

Examples of forms having dielectric multilayer films on both sides of the substrate (i) 102 include forms (B-1) to (B-3) shown in FIG. 1(B).
(B-1) is the light transmission band (Zd) on one surface of the substrate (i) 102 when measured from an angle of 5° with respect to the vertical direction of the optical filter (or substrate (i)). A first dielectric multilayer film 104a having mainly reflection characteristics is provided on the longer wavelength side (hereinafter also referred to as “wavelength region 1”), and an optical filter ( Or, when measured from an angle of 5° with respect to the vertical direction of the substrate (i)), the reflection characteristics are mainly on the shorter wavelength side (hereinafter also referred to as “wavelength region 2”) than the light transmission band (Zb). In this embodiment, a second dielectric multilayer film 104b having a structure is provided.

(B-2) is a form in which the first dielectric multilayer film 104a is provided on both sides of the substrate (i) 102. FIG.
(B-3) is the light transmission band (Zb) on one surface of the substrate (i) 102 when measured from an angle of 5° with respect to the vertical direction of the optical filter (or substrate (i)) and a light transmission band (Zd), and a third dielectric multilayer film 104c having reflection characteristics mainly in the wavelength region 1, and on the other surface of the substrate (i) 102, an optical filter Reflected mainly in the wavelength region between the light transmission band (Zb) and the light transmission band (Zd) and the wavelength region 2 when measured from an angle of 5 ° with respect to the vertical direction of the substrate (i)) In this mode, a fourth dielectric multilayer film 104d having specific properties is provided.

In addition, the optical filter 100c shown in FIG. is provided with a dielectric multilayer film 104 having mainly reflection properties in the visible light region and part of the near-infrared rays, specifically other than the wavelength region used for near-infrared sensing, and the other of the substrate (i) 102 In this mode, an antireflection film 106 having antireflection properties in the wavelength region (Zb and Zd) used for near-infrared sensing is provided on the surface. When the substrate (i) has sufficient absorption in the entire region of shorter wavelengths than the light transmission band (Zb) (for example, a wavelength region of 380 to 780 nm), one surface of the substrate (i) 102 has an optical A second dielectric multilayer film 104a having reflection characteristics mainly in the wavelength region 1 when measured from an angle of 5° with respect to the vertical direction of the filter (or substrate (i)), and a substrate ( i) The other surface of 102 may have an antireflection film 106 having antireflection properties in the wavelength region (Zb and Zd) used for near-infrared sensing. By combining a dielectric multilayer film and an antireflection film on the substrate (i), it is possible to reflect light unnecessary for sensing while increasing the transmittance in the wavelength region used for near-infrared sensing.

In addition, the optical filter 100d shown in FIG. 1D has antireflection properties in the visible light region and the wavelength region (Zb and Zd) used for near-infrared sensing on both surfaces of the optical filter (or the base material (i)). It is a form having an antireflection film 106a. When the substrate (i) has sufficient absorption properties in the visible light region and the light blocking bands (Za), (Zc) and (Ze), the dielectric multilayer film does not necessarily have the visible light region or the wavelength region 1 A dielectric multilayer film having antireflection properties can be preferably used in both the visible light region and the wavelength region used for near-infrared sensing.

The thickness of the optical filter may be appropriately selected according to the desired application, but it is preferable that the thickness is thin in consideration of the recent trend toward thinner and lighter information terminals. In particular, in optical sensor applications, it is extremely important to achieve both good optical properties (sensing light transmission properties, unnecessary light cut-off properties) and thinness, and the application of the optical filter of the present invention achieves this with conventional products. It is possible to combine these properties to an impossible level.

The thickness of the optical filter of the present invention is preferably 180 μm or less, more preferably 160 μm or less, still more preferably 150 μm or less, and particularly preferably 120 μm or less. Although the lower limit is not particularly limited, it is preferably 20 μm, for example, considering the strength and ease of handling of the optical filter.

[Base material]
FIGS. 2A to 2C show examples of the structure of the substrate (i). The substrate (i) 102 may include a resin layer containing one or more compounds (Z) having an absorption maximum in the wavelength range of 700 to 1000 nm, and may be a single layer or multiple layers.

Hereinafter, a resin layer containing at least one compound (Z) and a resin is also referred to as "resin layer (z)", and the other resin layer is simply referred to as "resin layer".
FIG. 2(A) shows a substrate (i) 102a having a single-layer structure, which is composed of a resin substrate (ii) 108 containing a compound (Z). This resin substrate (ii) corresponds to the aforementioned resin layer (z). FIG. 2(B) shows a substrate (i) 102b having a multilayer structure. A structure in which a resin layer (z) 112 such as an overcoat layer made of a curable resin or a thermoplastic resin is laminated. Note that layers corresponding to the resin layer (z) 112 may be provided on both sides of the support 110 . In FIG. 2C, a resin layer (z) 112 such as an overcoat layer made of a curable resin containing the compound (Z) is laminated on a resin substrate (ii) 108 containing the compound (Z). substrate (i) 102c is shown.

When it has a glass support, the glass support is preferably a colorless and transparent glass substrate containing no absorbent, from the viewpoint of the strength of the substrate (i) and the transmittance in the near-infrared wavelength region. Phosphate glass containing copper as an absorber tends to reduce the strength of the base material, and the transmittance in the near-infrared wavelength region decreases, which may hinder near-infrared sensing with high sensitivity.

In the case of having a resin support, curable resins are added to both sides of the resin support from the viewpoints of ease of adjusting optical properties, achievement of scratch-removing effect of the resin support, improvement of scratch resistance of the substrate, and the like. Alternatively, it is particularly preferable that a resin layer such as an overcoat layer made of a thermoplastic resin is laminated, and at least one of the resin layers contains the compound (Z).

It is particularly preferable that the substrate (i) includes a resin substrate (ii) containing the compound (Z). When such a substrate (i) is used, it is possible to achieve both thinness and resistance to cracking, and it can be suitably used for optical sensor devices.

The thickness of the substrate (i) is desirably selected so as to achieve both substrate strength and thinness, preferably 10 to 180 μm, more preferably 10 to 160 μm, even more preferably 15 to 150 μm, particularly preferably 20 to 120 μm. When the thickness of the base material (i) is within the above range, the optical filter using the base material (i) can be made thinner and lighter, and can be used particularly in various applications such as optical sensor devices mounted on mobile devices. It can be suitably used for the purpose.

<Compound (Z)>
The compound (Z) is not particularly limited as long as it has an absorption maximum in the wavelength region of 700 to 1000 nm, but it is preferably a solvent-soluble dye compound, and includes squarylium-based compounds, phthalocyanine-based compounds, naphthalocyanine-based compounds, It is more preferably at least one selected from the group consisting of croconium-based compounds, pyrrolopyrrole-based compounds, hexaphylline-based compounds, cyanine-based compounds, and boron dipyrromethene-based compounds. At least one compound selected from the group consisting of compounds, phthalocyanine compounds, naphthalocyanine compounds, and pyrrolopyrrole compounds is particularly preferred.

In the present invention, the compound (Z) preferably contains two or more compounds having different maximum absorption wavelengths. More specifically, one or more compounds (Z1) having an absorption maximum wavelength in the region of preferably 700 to 850 nm, more preferably 705 to 840 nm, particularly preferably 710 to 830 nm, and preferably 851 to 1000 nm, more preferably preferably contains one or more compounds (Z2) having a maximum absorption wavelength in the region of 855 to 970 nm, particularly preferably 860 to 950 nm.

Further, when the compound (Z) includes the compound (Z1) and the compound (Z2), the compound (Z1) having the longest absorption maximum wavelength on the long wavelength side and the compound (Z2) having the maximum absorption wavelength The difference in the maximum absorption wavelength from that on the short wavelength side is preferably 80 to 240 nm, more preferably 100 to 220 nm, and particularly preferably 110 to 200 nm.

When the absorption maximum wavelengths of the compound (Z1) and the compound (Z2) and the difference between them are within the above ranges, the light transmission band (Zb), the light blocking band (Zc) and the light transmission band (Zd) can be efficiently formed. is possible, excellent sensing performance can be achieved, and the design of the dielectric multilayer film can be simplified (cost reduction). The compound (Z1) and the compound (Z2) may be contained in the same resin layer or in separate resin layers. The form contained in is more preferable.

The compound (Z) may be synthesized by a generally known method. can be synthesized by referring to the method described in .

When the resin layer (z) is, for example, a resin substrate (ii) containing the compound (Z), the content of the compound (Z) is preferably 0.00 per 100 parts by mass of the resin. 01 to 2.0 parts by mass, more preferably 0.02 to 1.5 parts by mass, particularly preferably 0.03 to 1.0 parts by mass. Further, when the resin layer (z) is an overcoat layer or the like composed of a curable resin containing the compound (Z), which is laminated on a glass support or a base resin support, It is preferably 0.1 to 5.0 parts by mass, more preferably 0.2 to 4.0 parts by mass, particularly preferably 0.3 to 3.0 parts by mass, per 100 parts by mass of the resin forming the resin layer (z). It is 0 parts by mass. When the content of the compound (Z) is within the above range, good near-infrared absorption properties can be achieved.

<Compound (S)>
The optical filter of the present invention preferably contains, in addition to the compound (Z), a compound (S) having an absorption maximum in the wavelength region of 350 to 699 nm, and the layer containing the compound (S) is the compound (Z) may be the same as or different from the layer containing the

When the compound (S) and the compound (Z) are contained in the same layer, for example, a configuration in which the resin substrate (ii) further contains the compound (S), a glass support, or a resin support as a base 2, a structure in which a resin layer (z) such as an overcoat layer made of a curable resin containing the compound (S) and the compound (Z) is laminated. Further, when the compound (S) and the compound (Z) are contained in different layers, for example, the resin substrate (ii) has a resin layer such as an overcoat layer made of a curable resin containing the compound (S). A laminated structure, a structure in which a resin layer (z) such as an overcoat layer made of a curable resin containing the compound (Z) is laminated on the resin substrate (iii) containing the compound (S), and the above A configuration in which the resin substrate (ii) and the resin substrate (iii) are bonded together can be mentioned. From the standpoints of ease of adjustment of optical properties and production costs, a configuration in which the resin substrate (ii) further contains the compound (S) is particularly preferred.

The compound (S) is not particularly limited as long as it has an absorption maximum at a wavelength of 350 to 699 nm. It is preferable to contain at least one compound (Sb) having an absorption maximum in the region of 501 to 600 nm and a compound (Sc) having an absorption maximum in the wavelength region of 601 to 699 nm, and the compound (S- The difference in the maximum absorption wavelength between a) and the compound (Sb) is 50 to 140 nm, and the difference in the maximum absorption wavelength between the compound (Sb) and the compound (Sc) is 30 to 100 nm. is particularly preferred. When the compound (S) is contained in the resin layer, the compound (S) acts as a visible light absorber and also acts as a plasticizer for the resin layer to lower the glass transition temperature of the resin layer, resulting in , may reduce the heat resistance of the optical filter. On the other hand, when the compound (S) contains the compound (Sa), the compound (Sb), and the compound (Sc) satisfying the above conditions, unnecessary visible light can be efficiently cut off with a small addition amount. It is possible to minimize the decrease in the glass transition temperature of the resin layer.

The compound (S) is preferably a solvent-soluble dye compound, and includes squarylium-based compounds, phthalocyanine-based compounds, cyanine-based compounds, methine-based compounds, tetraazaporphyrin-based compounds, porphyrin-based compounds, and triarylmethane-based compounds. , subphthalocyanine compounds, perylene compounds, semisquarylium compounds, styryl compounds, phenazine compounds, pyridomethene-boron complex compounds, pyrazine-boron complex compounds, pyridone azo compounds, xanthene compounds, BODIPY (boron dipyrromethene )-based compounds, and is more preferably at least one selected from the group consisting of squarylium-based compounds, phthalocyanine-based compounds, cyanine-based compounds, methine-based compounds, triarylmethane-based compounds, xanthene-based compounds, and pyridone azo-based compounds. At least one selected from the group is particularly preferred.

Examples of commercially available products of the compound (S) include general visible-absorbing dyes and visible-absorbing pigments, but visible-absorbing dyes tend to be superior in efficiency of cutting off visible light and are therefore preferred.
The content of the compound (S) is such that the layer containing the compound (S) is, for example, a resin substrate (ii) containing the compound (Z) and the compound (S), or a resin containing the compound (S) In the case of substrate (iii), it is preferably 0.10 to 5.0 parts by mass, more preferably 0.25 to 3.5 parts by mass, and particularly preferably 0.50 parts by mass with respect to 100 parts by mass of the resin. ~2.0 parts by mass. Further, a layer containing the compound (S) is laminated on a resin substrate (ii) containing the compound (Z), a glass support, or a base resin support. In the case of an overcoat layer or the like made of a curable resin or the like, it is preferably 1.0 to 30.0 parts by mass, more preferably 2 parts by mass with respect to 100 parts by mass of the resin forming the resin layer containing the compound (S). 0 to 25.0 parts by mass, particularly preferably 3.0 to 20.0 parts by mass. When the content of the compound (S) is within the above range, good near-infrared absorption properties can be achieved. In particular, when the substrate (i) contains a resin substrate (ii) containing the compound (Z) and the compound (S), if the content of the compound (S) is within the above range, the resin substrate ( The decrease in the glass transition temperature of ii) can be suppressed, and an optical filter having excellent heat resistance can be obtained.

<Resin>
The resin support, the resin layer (z) laminated on the resin support, the glass support, or the like, the resin substrate (ii), and the resin substrate (iii) are formed using a resin. As such a resin, one kind may be used alone, or two or more kinds may be used.

The resin is not particularly limited as long as it does not impair the effects of the present invention. In order to obtain a film that can form a multilayer film, the glass transition temperature (Tg) is preferably 110 to 380°C, more preferably 115 to 370°C, still more preferably 120 to 360°C, and particularly preferably 130 to 300°C. and resins. When the glass transition temperature of the resin is within the above range, the dielectric multilayer film can be vapor-deposited at a higher temperature when the resin substrate is formed, and an optical filter having excellent crack resistance and weather resistance can be obtained. .

When the resin is used as a resin constituting the resin substrate (ii) containing the compound (S) and the compound (Z) or the resin substrate (iii) containing the compound (S), the resin substrate ( The difference between the glass transition temperature of ii) or the resin substrate (iii) and the glass transition temperature of the resin contained in the resin substrate (ii) or the resin substrate (iii) is preferably 0 to 10°C, more It is preferably 0 to 8°C, more preferably 0 to 5°C. As described above, the compound (S) may act as a plasticizer for the resin layer. The decrease in the glass transition temperature of iii) can be reduced, and an optical filter excellent in heat resistance and crack resistance can be obtained.

As for the resin, when a resin plate having a thickness of 0.1 mm is formed from the resin, the total light transmittance (JIS K7105) of the resin plate is preferably 75 to 95%, more preferably 78 to 95. %, particularly preferably 80 to 95%. If a resin having a total light transmittance within such a range is used, the obtained substrate exhibits good transparency as an optical film.

The polystyrene equivalent weight average molecular weight (Mw) of the resin measured by gel permeation chromatography (GPC) is usually 15,000 to 350,000, preferably 30,000 to 250,000. The average molecular weight (Mn) is usually 10,000-150,000, preferably 20,000-100,000.

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

≪Cyclic (poly)olefin resin≫
As the cyclic (poly)olefin resin, 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 resins obtained by hydrogenating said resins are preferred.

式（Ｘ₀）中、Ｒ^x1～Ｒ^x4はそれぞれ独立に、下記（i'）～（ix'）より選ばれる原子または基を表し、ｋ^x、ｍ^xおよびｐ^xはそれぞれ独立に、０～４の整数を表す。
（i'）水素原子
（ii'）ハロゲン原子
（iii'）トリアルキルシリル基
（iv'）酸素原子、硫黄原子、窒素原子またはケイ素原子を含む連結基を有する、置換または非置換の炭素数１～３０の炭化水素基
（v'）置換または非置換の炭素数１～３０の炭化水素基
（vi'）極性基（但し、（ii'）および（iv'）を除く。）
（vii'）Ｒ^x1とＲ^x2またはＲ^x3とＲ^x4とが、相互に結合して形成されたアルキリデン基（但し、前記結合に関与しないＲ^x1～Ｒ^x4は、それぞれ独立に前記（ｉ'）～（vi'）より選ばれる原子または基を表す。）
（viii'）Ｒ^x1とＲ^x2またはＲ^x3とＲ^x4とが、相互に結合して形成された単環もしくは多環の炭化水素環または複素環（但し、前記結合に関与しないＲ^x1～Ｒ^x4は、それぞれ独立に前記（i'）～（vi'）より選ばれる原子または基を表す。）
（ix'）Ｒ^x2とＲ^x3とが、相互に結合して形成された単環の炭化水素環または複素環（但し、前記結合に関与しないＲ^x1とＲ^x4は、それぞれ独立に前記（i'）～（vi'）より選ばれる原子または基を表す。）

In formula (X ₀ ), R ^x1 to R ^x4 each independently represent an atom or group selected from (i') to (ix') below, k ^x , m ^x and p ^x each independently represent 0 Represents an integer from ~4.
(i') a hydrogen atom (ii') a halogen atom (iii') a trialkylsilyl group (iv') a substituted or unsubstituted carbon number of 1 having a linking group containing an oxygen atom, a sulfur atom, a nitrogen atom or a silicon atom ~30 hydrocarbon group (v') substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms (vi') polar group (excluding (ii') and (iv'))
(vii') an alkylidene group formed by bonding R ^x1 and R ^x2 or R ^x3 and R ^x4 together (provided that R ^x1 to R ^x4 not involved in the bonding are each independently ) to represent an atom or group selected from (vi').)
(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 ^x4 each independently represents an atom or group selected from the above (i') to (vi').)
(ix') A monocyclic hydrocarbon ring or heterocyclic ring formed by bonding R ^x2 and R ^x3 together (provided that R ^x1 and R ^x4 not involved in the bonding are each independently ') to represent an atom or group selected from (vi').)

式（Ｙ₀）中、Ｒ^y1およびＲ^y2はそれぞれ独立に前記（i'）～（vi'）より選ばれる原子または基を表すか、Ｒ^y1とＲ^y2とが、相互に結合して形成された単環もしくは多環の脂環式炭化水素、芳香族炭化水素または複素環を表し、ｋ^yおよびｐ^yはそれぞれ独立に０～４の整数を表す。

In formula (Y ₀ ), R ^y1 and R ^y2 each independently represent an atom or group selected from the above (i′) to (vi′), or R ^y1 and R ^y2 are bonded to form each of k ^y and p ^y independently represents an integer of 0 to 4;

≪Aromatic polyether resin≫
The aromatic polyether resin preferably has at least one structural unit selected from the group consisting of structural units represented by the following formula (1) and structural units represented by the following formula (2).

式（１）中、Ｒ¹～Ｒ⁴はそれぞれ独立、炭素数１～１２の１価の有機基を示し、ａ～ｄはそれぞれ独立に０～４の整数を示す。

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

式（２）中、Ｒ¹～Ｒ⁴およびａ～ｄはそれぞれ独立に、前記式（１）中のＲ¹～Ｒ⁴およびａ～ｄと同義であり、Ｙは、単結合、－ＳＯ₂－または－ＣＯ－を示し、Ｒ⁵およびＲ⁶はそれぞれ独立に、ハロゲン原子、炭素数１～１２の１価の有機基またはニトロ基を示し、ｅおよびｆはそれぞれ独立に０～４の整数を示し、ｍは０または１を示す。但し、ｍが０のとき、Ｒ⁶はシアノ基ではない。

In formula (2), R ¹ to R ⁴ and a to d are each independently defined as R ¹ to R ⁴ and a to d in formula (1) above; Y is a single bond _; - or -CO-, R ⁵ and R ⁶ each independently represent a halogen atom, a monovalent organic group having 1 to 12 carbon atoms or a nitro group, e and f each independently represent an integer of 0 to 4 and m represents 0 or 1. However, when m is 0, R ⁶ is not a cyano group.

In addition, the aromatic polyether-based resin further has at least one structural unit selected from the group consisting of structural units represented by the following formula (3) and structural units represented by the following formula (4). is preferred.

式（３）中、Ｒ⁷およびＲ⁷はそれぞれ独立に炭素数１～１２の１価の有機基を示し、Ｚは、単結合、－Ｏ－、－Ｓ－、－ＳＯ₂－、－ＣＯ－、－ＣＯＮＨ－、－ＣＯＯ－または炭素数１～１２の２価の有機基を示し、ｇおよびｈはそれぞれ独立に０～４の整数を示し、ｎは０または１を示す。

In formula (3), R ⁷ and R ⁷ each independently represent a monovalent organic group having 1 to 12 carbon atoms, Z is a single bond, —O—, —S—, —SO ₂ —, —CO -, -CONH-, -COO- or a divalent organic group having 1 to 12 carbon atoms; g and h each independently represent an integer of 0 to 4; n represents 0 or 1;

式（４）中、Ｒ⁵、Ｒ⁶、Ｙ、ｍ、ｅおよびｆはそれぞれ独立に、前記式（２）中のＲ⁵、Ｒ⁶、Ｙ、ｍ、ｅおよびｆと同義であり、Ｒ⁷、Ｒ⁸、Ｚ、ｎ、ｇおよびｈはそれぞれ独立に、前記式（３）中のＲ⁷、Ｒ⁸、Ｚ、ｎ、ｇおよびｈと同義である。

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

≪Polyimide resin≫
The polyimide resin is not particularly limited as long as it is a polymer compound containing an imide bond in a repeating unit. Can be synthesized.

≪Fluorene polycarbonate resin≫
The fluorene polycarbonate-based resin is not particularly limited as long as it is a polycarbonate resin containing a fluorene moiety.

≪Fluorene polyester resin≫
The fluorene polyester-based resin is not particularly limited, and may be a polyester resin containing a fluorene moiety. can be done.

≪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. It is preferably a polymer containing 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 UV-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 is decomposed by ultraviolet rays to generate active radicals. can be listed. The acrylic UV-curable resin is a substrate obtained by laminating a resin layer (z) containing a compound (Z) and a curable resin on a glass support or a base resin support as the substrate (i). When using a substrate in which a resin layer such as an overcoat layer made of a curable resin or the like is laminated on a resin substrate (ii) containing a compound (Z), it is particularly preferably used as the curable resin. can do.

≪Commercially available products≫
Examples of commercially available products of the resin include the following commercially available products. Examples of commercially available cyclic (poly)olefin resins include Arton manufactured by JSR Corporation, Zeonor manufactured by Nippon Zeon Co., Ltd., APEL manufactured by Mitsui Chemicals, Inc., and TOPAS manufactured by Polyplastics Co., Ltd. . Sumika Excel PES manufactured by Sumitomo Chemical Co., Ltd. and the like can be mentioned as commercial products of polyether sulfone-based resins. Commercially available polyimide resins include Neoprim L manufactured by Mitsubishi Gas Chemical Co., Ltd., and the like. Commercial products of polycarbonate-based resins include Pure Ace manufactured by Teijin Limited. Commercially available fluorene polycarbonate-based resins include Iupizeta EP-5000 manufactured by Mitsubishi Gas Chemical Company, Inc., and the like. OKP4HT manufactured by Osaka Gas Chemicals Co., Ltd. and the like can be cited as commercial products of fluorene polyester-based resins. Examples of commercially available acrylic resins include Acryvure manufactured by Nippon Shokubai Co., Ltd., and the like. Commercially available silsesquioxane-based UV-curable resins include Silplus manufactured by Nippon Steel Chemical Co., Ltd., and the like.

<Other ingredients>
The base material (i) may further contain additives such as antioxidants, near-ultraviolet absorbers, and fluorescence quenchers as other components within a range that does not impair the effects of the present invention. The other components may be used singly or in combination of two or more.

Examples of near-ultraviolet absorbers include azomethine-based compounds, indole-based compounds, benzotriazole-based compounds, and triazine-based compounds.
Antioxidants include, for example, 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-t-butyl-4-hydroxyphenyl)propionate]methane, tris(2,6-di-t-butylphenyl)phosphite and the like.

These additives may be mixed with the resin or the like when manufacturing the base material, or may be added when synthesizing the resin. Further, the amount to be added is appropriately selected according to the desired properties, but it is usually 0.01 to 5.0 parts by mass, preferably 0.05 to 2.0 parts by mass, per 100 parts by mass of the resin. Department.

<Method for manufacturing base material>
When the substrate (i) is a substrate containing the resin substrate (ii) or (iii), the resin substrate can be formed, for example, by melt molding or cast molding. Furthermore, if necessary, a substrate having an overcoat layer laminated thereon can be produced by coating with a coating agent such as an antireflection agent, a hard coating agent and/or an antistatic agent after molding.

Substrate (i) is a resin layer (z ) is a laminated substrate, for example, a resin solution containing the compound (Z) is melt-molded or cast-molded onto a glass support, a base resin support, or the resin substrate (iii). , Preferably, after coating by a method such as spin coating, slit coating, or inkjet, the solvent is removed by drying, and if necessary, light irradiation or heating is performed to obtain a glass support or a base resin support. Alternatively, it is possible to produce a substrate in which the resin layer (z) is formed on the resin substrate (iii).

≪Melt molding≫
Specifically, melt-molding includes a method of melt-molding pellets obtained by melt-kneading a resin and a compound (Z), and a method of melt-molding a resin composition containing a resin and a compound (Z). method, or a method of melt-molding pellets obtained by removing the solvent from a resin composition containing the compound (Z), resin and solvent. Examples of melt molding methods include injection molding, melt extrusion molding, and blow molding.

≪Cast molding≫
Cast molding includes a method of casting a resin composition containing the compound (Z), a resin and a solvent on a suitable support and removing the solvent, or a method of removing the solvent from the compound (Z), a photocurable resin and/or thermosetting. It can also be produced by a method in which a curable composition containing a curable resin is cast on a suitable support, the solvent is removed, and the composition is cured by an appropriate technique such as ultraviolet irradiation or heating.

When the substrate (i) is a substrate made of a resin substrate (ii) containing the compound (Z), the substrate is subjected to cast molding, after which the coating film is peeled off from the molding support. In addition, the substrate (i) is an overcoat layer made of a curable resin containing the compound (Z) on a support such as a glass support or a base resin support. When the substrate is laminated with a resin layer (z) such as the above, the substrate can be obtained by not peeling off the coating film after cast molding.

[Dielectric multilayer film]
Dielectric multilayer films include those in which high refractive index material layers and low refractive index material layers are alternately laminated. A material having a refractive index of 1.7 or more can be used as a material constituting the high refractive index material layer, and a material having a refractive index of 1.7 to 2.5 is usually selected. Examples of such materials include titanium oxide, zirconium oxide, tantalum pentoxide, niobium pentoxide, lanthanum oxide, yttrium oxide, zinc oxide, zinc sulfide, indium oxide, etc., and titanium oxide, tin oxide and/or Alternatively, those containing a small amount (for example, 0 to 10% by mass relative to the main component) of cerium oxide or the like can be used.

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

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

The thickness of each of the high refractive index material layer and the low refractive index material layer is generally preferably 1 to 500 nm, more preferably 2 to 450 nm, particularly preferably 5 to 400 nm. When the thickness of each layer is within this range, control during film formation is easy, and from the relationship between the optical characteristics of reflection and refraction, there is a tendency to easily control the blocking and transmission of specific wavelengths.

The total number of laminated layers of the high refractive index material layer and the low refractive index material layer in the dielectric multilayer film is preferably 8 to 120 layers as a whole optical filter, more preferably 12 to 110 layers, and 16 layers. ~100 layers are particularly preferred. 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 warping of the optical filter and cracking of the dielectric multilayer film can be reduced. can do.

Here, in order to optimize the design of the dielectric multilayer film, for example, optical thin film design software (eg, EssentialMacleod, manufactured by ThinFilmCenter) is used to determine the light cut characteristics in the visible light region and the target near-infrared transmission band ( The parameters may be set so as to achieve both the light transmission characteristics of the wavelength region used for near-infrared sensing). For example, when using near infrared rays near 820 nm and near infrared rays near 950 nm for near infrared sensing, depending on the optical properties of the substrate (i), the target transmittance when measured from the vertical direction at a wavelength of 350 to 780 nm is 0%, the TargetTolerance value is 1, the target transmittance when measured from the vertical direction at a wavelength of 800 to 970 nm is 100%, the TargetTolerance value is 0.5, and the target when measured from the vertical direction at a wavelength of 1000 to 1200 nm With a transmittance of 0% and a TargetTolerance value of 0.8, a parameter setting method designed to have reflection characteristics other than the wavelength band used for near-infrared sensing, and a target when measured from the vertical direction at a wavelength of 700 to 970 nm With a transmittance of 100%, a TargetTolerance value of 0.5, and a target transmittance of 0% when measured from the vertical direction at a wavelength of 1000 to 1200 nm, a part of the visible light region to the wavelength band used for near-infrared sensing. Examples include a parameter setting method designed to have an antireflection effect and have reflection characteristics on the longer wavelength side than the wavelength band used for near-infrared sensing. These parameters can further subdivide the wavelength range according to the optical properties of the base material (i), and can also change the values of the ray incident angle and Target Tolerance to optimize the design. In addition, in the case of a structure having dielectric multilayer films on both sides of the substrate (i), both sides can be provided with dielectric multilayer films of the same design, or both sides can be provided with dielectric multilayer films of different designs.

[Other functional films]
The optical filter of the present invention is provided between the base material and the dielectric multilayer film, the surface of the base material opposite to the surface on which the dielectric multilayer film is provided, or the dielectric multilayer film, as long as the effects of the invention are not impaired. An antireflection film and a hard coating are applied to the surface of the film opposite to the surface on which the base material is provided, for the purposes of improving the surface hardness of the base material and dielectric multilayer film, improving chemical resistance, antistatic and scratch removal. A functional film such as a coat film or an antistatic film can be appropriately provided.

The optical filter of the present invention may contain one layer of the functional film described above, or may contain two or more layers. When the optical filter of the present invention contains two or more layers of such functional films, it may contain two or more similar layers or two or more different layers.

The method for laminating such a 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 on the base material or the dielectric multilayer film in the same manner as described above. Methods such as molding or cast molding can be used.

It can also be produced by applying a curable composition containing a coating agent and the like onto a base material or a dielectric multilayer film using a bar coater or the like, and then curing the film by ultraviolet irradiation or the like.

Examples of coating agents include ultraviolet (UV)/electron beam (EB) curable resins and thermosetting resins. Specifically, vinyl compounds, urethane, urethane acrylate, acrylate, and epoxy and epoxy acrylate resins. Curable compositions containing these coating agents include vinyl-based, urethane-based, urethane-acrylate-based, acrylate-based, epoxy-based and epoxy-acrylate-based curable compositions.

Moreover, the curable composition may contain a polymerization initiator. As the polymerization initiator, a known photopolymerization initiator or 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 together.

The mixing ratio of the polymerization initiator in the curable composition is preferably 0.1 to 10% by mass, more preferably 0.5 to 10% by mass, when the total amount of the curable composition is 100% by mass, and further It is preferably 1 to 5% by mass. When the blending ratio of the polymerization initiator is within the above range, the curable composition has excellent curing properties and handling properties, and functional films such as antireflection films, hard coat films, and antistatic films having desired hardness can be obtained. 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 and 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- Amides such as methylpyrrolidone can be mentioned. These solvents may be used singly or in combination of two or more.

The thickness of the functional membrane is preferably 0.1-20 μm, more preferably 0.5-10 μm, particularly preferably 0.7-5 μm.
In addition, for the purpose of improving the adhesion between the base material and the functional film and/or the dielectric multilayer film, and the adhesion between the functional film and the dielectric multilayer film, the surface of the base material, the functional film, or the dielectric multilayer film may be coated with corona. Surface treatment such as treatment or plasma treatment may be performed.

[Applications of optical filters]
The optical filter of the present invention is characterized by having excellent visible light cutting performance and light transmission characteristics in two or more wavelength regions used for near-infrared sensing. Therefore, it is useful for optical sensor devices. In particular, it is useful for optical sensors mounted on smart phones, tablet terminals, mobile phones, wearable devices, automobiles, televisions, game machines, drones, and the like. Examples of optical sensors include biometric sensors such as iris authentication sensors, face authentication sensors, fingerprint authentication sensors, and blood oxygen concentration sensors, ambient light sensors, and illuminance sensors. You can also

EXAMPLES The present invention will be described in more detail below based on examples, but the present invention is not limited to these examples. In addition, "parts" means "parts by mass" unless otherwise specified. In addition, the method for measuring each physical property value and the method for evaluating physical properties are as follows.

<Molecular weight>
The molecular weight of the resin was measured by the following method (a) or (b) in consideration of the solubility of each resin in a solvent.
(a) Using a gel permeation chromatography (GPC) device (150C type, column: H type column manufactured by Tosoh Corporation, developing solvent: o-dichlorobenzene) manufactured by WATERS, mass average molecular weight in terms of standard polystyrene (Mw) and number average molecular weight (Mn) were measured.
(b) Using a Tosoh GPC apparatus (HLC-8220, column: TSKgelα-M, developing solvent: THF), the mass average molecular weight (Mw) and number average molecular weight (Mn) in terms of standard polystyrene were measured.
For the resin synthesized in Resin Synthesis Example 3, which will be described later, the logarithmic viscosity was measured by the following method (c) instead of the molecular weight measurement by the above method.
(c) A portion of the polyimide resin solution was poured into anhydrous methanol to precipitate the polyimide resin, which was separated from unreacted monomers by filtration. 0.1 g of polyimide obtained by vacuum drying at 80 ° C. for 12 hours is dissolved in 20 mL of N-methyl-2-pyrrolidone, and the logarithmic viscosity (μ) at 30 ° C. using a Canon-Fenske viscometer is calculated by the following formula. asked.
μ={ln( _ts / _t0 )}/C
t ₀ : Flow-down time of solvent t _s : Flow-down time of dilute polymer solution C: 0.5 g/dL

<Glass transition temperature (Tg)>
Using a differential scanning calorimeter (DSC6200) manufactured by SII Nanotechnologies Co., Ltd., the temperature was measured at a rate of temperature increase of 20°C per minute under a nitrogen stream.

<Spectral transmittance>
The transmittance in each wavelength region of the optical filter was measured using a spectrophotometer (U-4100) manufactured by Hitachi High-Technologies Corporation.
Here, for the transmittance measured in the vertical direction of the optical filter, the light 1 transmitted vertically through the optical filter 2 is measured by the spectrophotometer 3 as shown in FIG. In the transmittance measured at an angle of 30° with respect to the direction, the light 1 ′ transmitted at an angle of 30° with respect to the vertical direction of the optical filter 2 as shown in FIG. It was measured.

[Synthesis example]
The dye compounds used in the following examples were synthesized by a generally known method. General synthesis methods include, for example, Japanese Patent No. 3366697, Japanese Patent No. 2846091, Japanese Patent No. 2864475, Japanese Patent No. 3703869, JP-A-60-228448, JP-A-1-146846, Japanese Patent Application Laid-Open No. 1-228960, Japanese Patent No. 4081149, Japanese Patent Application Laid-Open No. 63-124054, “Phthalocyanine-Chemistry and Function-” (IPC, 1997), Japanese Patent Application Laid-Open No. 2007-169315, Japanese Patent Application Laid-Open No. 2009 -108267, JP-A-2010-241873, Japanese Patent No. 3699464, Japanese Patent No. 4740631, and the like.

<Resin Synthesis Example 1>
8-methyl-8-methoxycarbonyltetracyclo[4.4.0.12,5.17,10]dodeca-3-ene (hereinafter also referred to as “DNM”) 100 represented by the following formula (X ₁ ) 18 parts of 1-hexene (molecular weight modifier) and 300 parts of toluene (solvent for ring-opening polymerization reaction) were placed in a reaction vessel purged with nitrogen, and the solution was heated to 80°C. Next, 0.2 part of a toluene solution of triethylaluminum (0.6 mol/liter) and 0.2 part of a toluene solution of methanol-modified tungsten hexachloride (concentration: 0.025 mol/liter) were added as polymerization catalysts to the solution in the reaction vessel. 9 parts were added, and this solution was heated and stirred at 80° C. for 3 hours to carry out ring-opening polymerization reaction to obtain a ring-opening polymer solution. The polymerization conversion rate in this polymerization reaction was 97%.

An autoclave was charged with 1,000 parts of the ring-opened polymer solution thus obtained, and 0.12 part of RuHCl(CO)[P(C ₆ H ₅ ) ₃ ] ₃ was added to the ring-opened polymer solution. Then, under the conditions of a hydrogen gas pressure of 100 kg/cm ² and a reaction temperature of 165° C., a hydrogenation reaction was carried out by heating and stirring for 3 hours. After cooling the resulting reaction solution (hydrogenated polymer solution), hydrogen gas was released. This reaction solution was poured into a large amount of methanol to separate and recover a solidified product, which was dried to obtain a hydrogenated polymer (hereinafter also referred to as "resin A"). The resulting resin A had a number average molecular weight (Mn) of 32,000, a mass average molecular weight (Mw) of 137,000, and a glass transition temperature (Tg) of 165°C.

<Resin Synthesis Example 2>
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, the four-necked flask was equipped with a thermometer, a stirrer, a three-way cock with a nitrogen inlet tube, a Dean-Stark tube and a cooling tube. Then, after the inside of the flask was replaced with nitrogen, the obtained solution was reacted at 140° C. for 3 hours, and the generated water was removed from the Dean-Stark tube at any time. When the formation of water was no longer observed, the temperature was gradually raised to 160° C., and the reaction was carried out at that temperature for 6 hours. After cooling to room temperature (25° C.), the produced salt was removed with a filter paper, the filtrate was poured into methanol to reprecipitate, and the filtrate (residue) was isolated by filtration. The obtained filter cake was vacuum-dried overnight at 60° C. to obtain a white powder (hereinafter also referred to as “resin B”) (yield 95%). The obtained resin B had a number average molecular weight (Mn) of 75,000, a mass average molecular weight (Mw) of 188,000, and a glass transition temperature (Tg) of 285°C.

<Resin Synthesis Example 3>
1,4-bis(4-amino-α,α -Dimethylbenzyl)benzene 27.66 g (0.08 mol) and 4,4'-bis(4-aminophenoxy)biphenyl 7.38 g (0.02 mol) were charged, and γ-butyrolactone 68.65 g and N, It was dissolved in 17.16 g of N-dimethylacetamide. The resulting solution was cooled to 5° C. using an ice water bath, and 22.62 g (0.1 mol) of 1,2,4,5-cyclohexanetetracarboxylic dianhydride and an imidization catalyst were added while maintaining the same temperature. 0.50 g (0.005 mol) of triethylamine was added all at once. After the addition was completed, the temperature was raised to 180° C., and the mixture was refluxed for 6 hours while distilling off the distillate as needed. After completion of the reaction, the mixture was air-cooled until the internal temperature reached 100° C., diluted with 143.6 g of N,N-dimethylacetamide, cooled with stirring, and 264.16 g of a polyimide resin solution with a solid content concentration of 20% by mass. got A portion of this polyimide resin solution was poured into 1 L of methanol to precipitate polyimide. The filtered polyimide 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”). When the IR spectrum of the obtained resin C was measured, absorption at 1704 cm ^-1 and 1770 cm ^-1 peculiar to the imide group was 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 resin substrate and transmitting near-infrared rays having a wavelength of about 820 nm and a wavelength of about 950 nm was produced according to the following procedure and conditions.
In a container, 100 parts of Resin A obtained in Resin Synthesis Example 1, compound (a-1) represented by the following formula (a-1) as compound (Z) (maximum absorption wavelength in dichloromethane: 738 nm) 0.28 and 0.06 parts of the compound (a-2) (absorption maximum wavelength 882 nm in dichloromethane) represented by the following formula (a-2), and methylene chloride to form a solution with a resin concentration of 20% by mass. prepared. 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. for 8 hours under reduced pressure to obtain a substrate made of a resin substrate having a thickness of 0.1 mm, a length of 60 mm and a width of 60 mm. FIG. 4 shows the measurement results of the spectral transmittance of this base material.

続いて、得られた基材の片面に誘電体多層膜（Ｉ）を形成し、さらに基材のもう一方の面に誘電体多層膜（II）を形成し、厚さ約０．１０９ｍｍの光学フィルターを得た。

Subsequently, a dielectric multilayer film (I) is formed on one side of the obtained base material, and a dielectric multilayer film (II) is formed on the other side of the base material to form an optical film having a thickness of about 0.109 mm. got a filter.

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. (54 layers in total). The dielectric multilayer film (II) is formed by alternately laminating silica (SiO ₂ ) layers and titania (TiO ₂ ) layers at a vapor deposition temperature of 100° C. (24 layers in total). In both the dielectric multilayer films (I) and (II), the silica layer and the titania layer are arranged in the order of titania layer, silica layer, titania layer, . . . silica layer, titania layer, silica layer from the substrate side. They are alternately laminated, and the outermost layer of the optical filter is a silica layer.

The dielectric multilayer films (I) and (II) were designed as follows.
The thickness of each layer and the number of layers should be determined according to the wavelength dependence of the refractive index of the base material and the absorption characteristics of the compound (Z) used so as to achieve the desired light blocking characteristics in the visible light region and the desired transmission characteristics in the near infrared region. In addition, optimization was performed using optical thin film design software (Essential Macleod, manufactured by Thin Film Center). When optimizing, in this example, input parameters (target values) to the software were as shown in Table 1 below.

As a result of optimizing the film configuration, in Example 1, the dielectric multilayer film (I) is composed of alternately laminated silica layers with a thickness of 20 to 489 nm and titania layers with a thickness of 12 to 73 nm. The dielectric multilayer film (II) is a multilayer vapor deposition film having 24 layers, in which a silica layer having a thickness of 154 to 519 nm and a titania layer having a thickness of 119 to 194 nm are alternately laminated. rice field. Table 4 shows an example of the optimized film configuration.

得られた光学フィルターの垂直方向および垂直方向に対して３０°の角度から測定した分光透過率を測定し、各波長領域における光学特性を評価した。結果を図５および表９に示す。

The spectral transmittance measured at an angle of 30° with respect to the vertical direction and the vertical direction of the obtained optical filter was measured to evaluate the optical characteristics in each wavelength region. The results are shown in FIG. 5 and Table 9.

[Example 2]
In Example 2, an optical filter having a substrate made of a resin substrate and transmitting near-infrared rays having a wavelength of about 820 nm and a wavelength of about 950 nm was produced by the following procedure and conditions.
In Example 1, as the compound (Z), in addition to 0.28 parts of the compound (a-1) and 0.06 parts of the compound (a-2), the compound represented by the following formula (a-3) (a- 3) Using 0.15 parts (maximum absorption wavelength 704 nm in dichloromethane), further compound (s-1) represented by the following formula (s-1) as compound (S) (absorption in dichloromethane Maximum wavelength 429 nm) 0.40 parts, compound (s-2) represented by the following formula (s-2) (absorption maximum wavelength 550 nm in dichloromethane) 0.40 parts and represented by the following formula (s-3) A resin substrate containing compound (Z) was obtained in the same procedure and under the same conditions as in Example 1, except that 0.40 parts of compound (s-3) (maximum absorption wavelength in dichloromethane: 606 nm) was used. FIG. 6 shows the spectral transmittance measurement results of this base material.

A base material made of a resin substrate was prepared in the same procedure as in Example 1. Next, a dielectric multilayer film (III) is formed on one side of the obtained substrate in the same manner as in Example 1 except that the design of the dielectric multilayer film (the number of layers and the thickness of each layer) is different, and A dielectric multilayer film (IV) was formed on the other side of the substrate to obtain an optical filter with a thickness of about 0.109 mm.

The dielectric multilayer films (III) and (IV) were designed in the same procedure as in Example 1, except that the input parameters (Target values) to the software were as shown in Table 3 below. Table 4 shows an example of the optimized film configuration.

得られた光学フィルターの垂直方向および垂直方向に対して３０°の角度から測定した分光透過率を測定し、各波長領域における光学特性を評価した。結果を図７および表９に示す。

The spectral transmittance measured at an angle of 30° with respect to the vertical direction and the vertical direction of the obtained optical filter was measured to evaluate the optical characteristics in each wavelength region. The results are shown in FIG. 7 and Table 9.

[Example 3]
In Example 3, an optical filter having a substrate made of a resin substrate having resin layers on both sides and transmitting near-infrared rays having a wavelength of about 820 nm and a wavelength of about 950 nm was produced according to the following procedure and conditions.

A resin substrate containing compound (Z) and compound (S) was obtained in the same procedure and under the same conditions as in Example 2.
A resin composition (1) having the following composition was applied to one side of the obtained resin substrate using a bar coater and heated in an oven at 70° C. for 2 minutes to evaporate and remove the solvent. At this time, the coating conditions of the bar coater were adjusted so that the thickness after drying was 2.5 μm. Next, exposure was performed using a conveyor type exposure machine (exposure amount: 500 mJ/cm ² , 200 mW) to cure the resin composition (1) to form a resin layer on the resin substrate. Similarly, a base material having a resin layer formed of the resin composition (1) on the other side of the resin substrate and having resin layers on both sides of the resin substrate containing the compound (Z) and the compound (S) got

Resin composition (1): 60 parts by mass of tricyclodecanedimethanol acrylate, 40 parts by mass of dipentaerythritol hexaacrylate, 5 parts by mass of 1-hydroxycyclohexylphenyl ketone, methyl ethyl ketone (solvent, solid content concentration (TSC): 30%)
Subsequently, in the same procedure as in Example 2, dielectric multilayer films were formed on both sides of the obtained base material to obtain an optical filter with a thickness of about 0.109 mm.
The spectral transmittance measured at an angle of 30° with respect to the vertical direction and the vertical direction of the obtained optical filter was measured to evaluate the optical characteristics in each wavelength region. Table 9 shows the results.

[Example 4]
In Example 4, an optical filter having a base material made of a glass substrate having a resin layer (z) containing a compound (Z) on one side and transmitting near infrared rays having a wavelength of about 820 nm and a wavelength of about 950 nm was manufactured by the following procedure. and conditions.

A transparent glass substrate "OA-10G (thickness 200 um)" (manufactured by Nippon Electric Glass Co., Ltd.) cut to a size of 60 mm long and 60 mm wide was coated with a resin composition (2) having the following composition with a spin coater, The solvent was removed by volatilization by heating on a hot plate at 80° C. for 2 minutes. At this time, the coating conditions of the spin coater were adjusted so that the thickness after drying was 10 μm. Next, exposure is performed using a conveyor-type exposure machine (exposure amount: 500 mJ/cm ² , 200 mW) to cure the resin composition (2), and the glass substrate having the resin layer (z) containing the compound (Z) is exposed. A base material was obtained.
Resin composition (2): 20 parts by mass of tricyclodecanedimethanol acrylate, 80 parts by mass of dipentaerythritol hexaacrylate, 4 parts by mass of 1-hydroxycyclohexylphenyl ketone, 2.8 parts by mass of compound (a-1), compound ( a-2) 0.6 parts by mass, compound (a-3) 1.5 parts by mass, compound (s-1) 4.0 parts by mass, compound (s-2) 4.0 parts by mass, compound (s- 3) 4.0 parts by mass, methyl ethyl ketone (solvent, TSC: 35%)

Subsequently, a dielectric multilayer film (V) was formed on one side of the substrate obtained in the same manner as in Example 2 except that the design of the dielectric multilayer film (the number of layers and the thickness of each layer) was different, and A dielectric multilayer film (VI) was formed on the other surface of the substrate to obtain an optical filter with a thickness of about 0.216 mm.

The dielectric multilayer films (V) and (VI) were designed in the same procedure as in Example 1, except that the input parameters (Target values) to the software were set as shown in Table 5 below. Table 6 shows an example of the optimized film configuration.

得られた光学フィルターの垂直方向および垂直方向に対して３０°の角度から測定した分光透過率を測定し、各波長領域における光学特性を評価した。結果を図８および表９に示す。

The spectral transmittance measured at an angle of 30° with respect to the vertical direction and the vertical direction of the obtained optical filter was measured to evaluate the optical characteristics in each wavelength region. The results are shown in FIG. 8 and Table 9.

[Example 5]
In Example 5, an optical filter having a base material made of a resin substrate having a resin layer (z) containing a compound (Z) on both sides and transmitting near infrared rays having a wavelength of about 820 nm and a wavelength of about 950 nm was manufactured by the following procedure. and conditions.

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

In the same procedure as in Example 3, except that the resin composition (2) was used instead of the resin composition (1) and the film forming conditions were adjusted so that the thickness after drying was 5.0 μm. A resin layer was formed on both sides of the obtained resin substrate to obtain a substrate composed of a resin substrate having a resin layer (z) containing the compound (Z) on both surfaces.

Subsequently, by the same procedure as in Example 2, dielectric multilayer films were formed on both sides of the obtained base material to obtain an optical filter with a thickness of about 0.119 mm. The spectral transmittance measured at an angle of 30° with respect to the vertical direction and the vertical direction of the obtained optical filter was measured to evaluate the optical characteristics in each wavelength region. Table 9 shows the results.

[Example 6]
In Example 6, an optical filter having a substrate made of a resin substrate and transmitting near-infrared rays having a wavelength of about 860 nm and a wavelength of about 1030 nm was produced by the following procedure and conditions.

In Example 3, as the compound (Z), 0.20 parts of the compound (a-1), 0.15 parts of the compound (a-3), and the compound (a-4) represented by the following formula (a-4) (Maximum absorption wavelength in dichloromethane: 776 nm) 0.10 parts and compound (a-5) represented by the following formula (a-5) (maximum absorption wavelength: 933 nm in dichloromethane) were used. A substrate having resin layers on both sides of a resin substrate containing compound (Z) and compound (S) was obtained in the same procedure and under the same conditions as in Example 3, except for the above. FIG. 9 shows the measurement results of the spectral transmittance of this base material.

続いて、誘電体多層膜の設計（層数および各層の厚み）が異なること以外は実施例２と同様の手順で得られた基材の片面に誘電体多層膜（VII）を形成し、さらに基材のもう一方の面に誘電体多層膜（VIII）を形成し、厚さ約０．１１０ｍｍの光学フィルターを得た。

Subsequently, a dielectric multilayer film (VII) was formed on one side of the substrate obtained in the same manner as in Example 2 except that the design of the dielectric multilayer film (the number of layers and the thickness of each layer) was different, and A dielectric multilayer film (VIII) was formed on the other surface of the substrate to obtain an optical filter with a thickness of about 0.110 mm.

The dielectric multilayer films (VII) and (VIII) were designed in the same procedure as in Example 1, except that the input parameters (Target values) to the software were as shown in Table 7 below. Table 8 shows an example of the optimized film configuration.

得られた光学フィルターの垂直方向および垂直方向に対して３０°の角度から測定した分光透過率を測定し、各波長領域における光学特性を評価した。結果を図１０および表９に示す。

The spectral transmittance measured at an angle of 30° with respect to the vertical direction and the vertical direction of the obtained optical filter was measured to evaluate the optical characteristics in each wavelength region. The results are shown in FIG. 10 and Table 9.

[Examples 7-9]
A substrate and an optical filter were prepared in the same manner as in Example 2, except that the resin was changed as shown in Table 9. Table 9 shows the optical properties of the obtained optical filter.

[Comparative Example 1]
A substrate and an optical filter were prepared in the same manner as in Example 1, except that the compound (Z) was not used. The optical properties of the obtained optical filter are shown in FIG. 11 and Table 9. Since the optical filter of Comparative Example 1 had only a single transmission band in the near-infrared wavelength region, Za, Zb, Zc, Zd and Ze could not be defined.

[Comparative Example 2]
A substrate and an optical filter were prepared in the same manner as in Example 2, except that the compound (Z) was not used. The optical properties of the obtained optical filter are shown in FIG. 12 and Table 9. In addition, since the optical filter of Comparative Example 2 had only a single transmission band in the near-infrared wavelength region, Ze could not be determined from Za, Zb, Zc, and Zd.

表９における基材の構成、各種化合物などに関する記号等の内容は、下記の通りである。

The contents of symbols and the like relating to the composition of the base material and various compounds in Table 9 are as follows.

<Form of base material>
Form (1): Form consisting of a resin substrate containing the compound (Z) Form (2): Form having resin layers on both sides of the resin substrate containing the compound (Z) Form (3): One surface of the glass substrate Form (4): Form having resin layers (z) containing compound (Z) on both sides of a resin substrate Form (5): Form containing compound (Z) Form (6): Form having a resin layer on both sides of a resin substrate containing compound (S) but not containing compound (Z) <Resin>
Resin A: Cyclic olefin resin (resin synthesis example 1, glass transition temperature 165°C)
Resin B: Aromatic polyether resin (resin synthesis example 2, glass transition temperature 285°C)
Resin C: polyimide resin (Resin Synthesis Example 3, glass transition temperature 310° C.)
Resin D: Cyclic olefin resin "Zeonor 1420R" (manufactured by Nippon Zeon Co., Ltd., glass transition temperature 136 ° C.)
<Glass substrate>
Glass substrate (1): Transparent glass substrate “OA-10G (thickness 200 μm)” cut to a size of 60 mm long and 60 mm wide (manufactured by Nippon Electric Glass Co., Ltd.)
<Compound (Z)>
a-1: compound (a-1) represented by formula (a-1) (maximum absorption wavelength in dichloromethane: 738 nm)
a-2: Compound (a-2) represented by formula (a-2) (maximum absorption wavelength in dichloromethane: 882 nm)
a-3: Compound (a-3) represented by formula (a-3) (maximum absorption wavelength in dichloromethane: 704 nm)
a-4: Compound (a-4) represented by formula (a-4) (maximum absorption wavelength in dichloromethane: 776 nm)
a-5: Compound (a-5) represented by formula (a-5) (maximum absorption wavelength in dichloromethane: 933 nm)
<Compound (S)>
s-1: compound (s-1) represented by formula (s-1) (maximum absorption wavelength in dichloromethane: 429 nm)
s-2: compound (s-2) represented by formula (s-2) (maximum absorption wavelength in dichloromethane: 550 nm)
s-3: compound (s-3) represented by formula (s-3) (maximum absorption wavelength in dichloromethane: 606 nm)
<Solvent>
Solvent (1): methylene chloride Solvent (2): N,N-dimethylacetamide Solvent (3): cyclohexane/xylene (mass ratio: 7/3)
In Table 9, the drying conditions for the resin substrates of Examples and Comparative Examples are as follows. Before drying under reduced pressure, the coating film was peeled off from the glass plate.

<Drying Conditions for Resin Substrate>
Condition (1): 20°C/8hr → 100°C/8hr under reduced pressure
Condition (2): 60°C/8hr → 80°C/8hr → 140°C/8hr under reduced pressure
Condition (3): 60°C/8hr → 80°C/8hr → 100°C/24hr under reduced pressure

DESCRIPTION OF SYMBOLS 1, 1'... Light 2... Optical filter 3... Spectrophotometer 100... Optical filter 102... Base material 104... Dielectric multilayer film 106... Antireflection film 108. ... resin substrate containing compound (Z) 110 ... support 112 ... resin layer

Claims (11)

Having a resin layer containing a compound (Z) having an absorption maximum in the wavelength range of 700 to 1000 nm and a dielectric multilayer film,
meet the following requirements (a) and (b),
An optical filter that has two or more different transmission bands in the near-infrared region and blocks visible light :
(a) In the wavelength region of 380 to 700 nm, the average value of transmittance when measured from the direction perpendicular to the surface direction of the optical filter is 5% or less;
(b) having a light blocking band (Za), a light transmitting band (Zb), a light blocking band (Zc), a light transmitting band (Zd) and a light blocking band (Ze) in a wavelength range of 700 to 1200 nm, respectively; The center wavelength of the band of is Za<Zb<Zc<Zd<Ze,
The light blocking band (Ze) is a wavelength band having a transmittance of 5% or less when measured from a direction perpendicular to the surface of the optical filter in a wavelength region of 700 to 1200 nm, and a width of 5 nm or more. is . The optical filter of claim 1 , further satisfying requirement (c):
(c) In the light transmission band (Zb), Xa (nm) is the wavelength on the shortest wavelength side at which the transmittance when measured from the direction perpendicular to the surface of the optical filter is 15%. When the value of the wavelength on the longer wavelength side is Xb (nm), the value of Y1 represented by Y1=(Xa+Xb)/2 is 750 to 950 nm. The optical filter according to claim 1 or 2 , further satisfying the following requirement (d):
(d) In the light transmission band (Zd), Xc (nm) is the value of the wavelength on the shortest wavelength side at which the transmittance when measured from the direction perpendicular to the surface of the optical filter is 20%. When the value of the wavelength on the long wavelength side is Xd (nm), the value of Y2 represented by Y2=(Xc+Xd)/2 is 900 to 1200 nm. The compound (Z) is at least selected from the group consisting of squarylium-based compounds, phthalocyanine-based compounds, naphthalocyanine-based compounds, croconium-based compounds, pyrrolopyrrole-based compounds, hexaphylline-based compounds, cyanine-based compounds and boron dipyrromethene-based compounds. 4. The optical filter according to any one of claims 1 to 3 , which is a single compound. The optical filter according to any one of claims 1 to 4 , wherein the compound (Z) includes two or more compounds having different maximum absorption wavelengths. The compound (Z) comprises one or more compounds (Z1) having an absorption maximum in the wavelength range of 700 to 850 nm and one or more compounds (Z2) having an absorption maximum in the wavelength range of 851 to 1000 nm. 5. The optical filter according to any one of items 1 to 4 . The difference in maximum absorption wavelength between the compound (Z1) having the longest absorption wavelength on the long wavelength side and the compound (Z2) having the maximum absorption wavelength on the short wavelength side is 80 to 240 nm. 7. The optical filter of claim 6 , comprising: The optical filter according to any one of claims 1 to 7 , further comprising a compound (S) having an absorption maximum in the wavelength range of 350-699 nm. The resin constituting the 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, and a polyarylate resin. , polysulfone-based resin, polyethersulfone-based resin, polyparaphenylene-based resin, polyamideimide-based resin, polyethylene naphthalate-based resin, fluorinated aromatic polymer-based resin, (modified) acrylic-based resin, epoxy-based resin, allyl ester 9. The resin according to any one of claims 1 to 8 , which is at least one resin selected from the group consisting of system-curable resins, silsesquioxane-based ultraviolet-curable resins, acrylic-based ultraviolet-curable resins, and vinyl-based ultraviolet-curable resins. 2. The optical filter according to item 1. 10. The optical filter according to any one of claims 1 to 9 , which is used for an optical sensor device. An optical sensor device comprising the optical filter according to any one of claims 1-10 .

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