Optical filter

Abstract

To provide an optical filter advantageous for exhibiting desired transmissivity characteristics even without comprising a near infrared ray reflection film.SOLUTION: An optical filter 1a comprises a first light absorber 11 and a second light absorber 12. The first light absorber 11 contains an organic dye. The second light absorber 12 contains a copper component, and absorbs at least part of infrared rays. The optical filter exhibits a first transmission spectrum satisfying the following conditions: (I) an average value TA450-600 of a transmissivity in a wavelength range of 450 nm to 600 nm is 76% or more; (II) a first cutoff wavelength λF falls in a range of 360 nm to 450 nm; (III) a second cutoff wavelength λS falls in a range of 600 nm to 700 nm; and (IV) a maximum value TM700-750 of a transmissivity in a wavelength range of 700 nm to 750 nm is 5% or less.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to optical filters. [Background technology]

[0002] In imaging devices equipped with imaging elements such as CCDs (Charge Coupled Devices) and CMOSs (Complementary Metal Oxide Semiconductors), various optical filters are placed in front of the imaging elements to obtain images with good color reproducibility. The imaging elements are sensitive to light over a wide wavelength range, from the ultraviolet to the infrared regions. Meanwhile, human visual sensitivity is limited to the visible light region. Therefore, a known technique involves placing an optical filter in front of the imaging element to block part of the infrared or ultraviolet light, so that the image obtained by the imaging device closely resembles the image perceived by humans.

[0003] For example, Patent Document 1 describes an infrared cut filter that includes a near-infrared reflective film and an absorbing film, with these films having predetermined characteristics. The near-infrared reflective film is formed by alternatingly laminating two or more materials with different refractive indices. This infrared cut filter can achieve the desired optical performance of an imaging device.

[0004] Meanwhile, a technology using an optical filter such as a near-infrared cut filter is known to allow only visible light to reach the environmental sensor of an information terminal device and match the human visual sensitivity with the display brightness or color tone. For example, Patent Document 2 describes an optical filter for an environmental sensor. This optical filter has a layer containing a compound (A) having an absorption maximum in the wavelength range of 650 nm to less than 800 nm and a compound (B) having an absorption maximum in the wavelength range of 800 nm to 1850 nm. Compound (A) is at least one compound selected from the group consisting of squarylium-based compounds, phthalocyanine-based compounds, and cyanine-based compounds. Compound (B) is at least one compound selected from the group consisting of near-infrared absorbing particles, squarylium-based compounds, phthalocyanine-based compounds, naphthalocyanine-based compounds, croconium-based compounds, cyanine-based compounds, diimonium-based compounds, metal dithiolate-based compounds, and pyrrolopyrrole-based compounds. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] International Publication No. 2017 / 006571 [Patent Document 2] International Publication No. 2018 / 221424 Summary of the Invention [Problem to be solved by the invention]

[0006] Considering the performance requirements for optical filters in recent years, the technology described in Patent Document 1 may need to be further improved to increase the transmittance in the visible light range. The technology described in Patent Document 2 uses a light absorber made of an organic compound, and therefore, when used in an optical filter, the wavelength band that is blocked by the light may be insufficient. To compensate for this, a near-infrared reflective film made of a dielectric multilayer film or the like must also be provided. This is disadvantageous from the perspective of suppressing flare and ghosting or reducing manufacturing costs.

[0007] In view of the above circumstances, the present invention provides an optical filter that is advantageous in that it exhibits desired transmittance characteristics without including a near-infrared reflective film. [Means for solving the problem]

[0008] The present invention provides An optical filter, a first light absorber comprising an organic dye; a second light absorber containing a copper component and absorbing at least a portion of infrared light; When light having a wavelength in the range of 300 nm to 1200 nm is incident on the optical filter, the optical filter exhibits a first transmission spectrum that satisfies the following conditions (I), (II), (III), and (IV): An optical filter is provided. (I) The average transmittance in the wavelength range of 450 nm to 600 nm is 76% or more. (II) The first cutoff wavelength, which is a wavelength showing a transmittance of 50% in the wavelength range of 350 nm to 470 nm, is in the range of 360 nm to 450 nm. (III) A wavelength that exhibits 50% transmittance in the wavelength range of 580 nm to 720 nm. Two cutoff wavelengths are in the range of 600 nm to 700 nm. (IV) The maximum transmittance in the wavelength range of 700 nm to 750 nm is 5% or less. [Effects of the Invention]

[0009] The optical filter described above is made of a light absorber, which is advantageous in that it exhibits desired transmittance characteristics, and is capable of transmitting light in a wavelength range corresponding to the visible light region and blocking light in the ultraviolet and infrared wavelength ranges without the need for a light reflecting film. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a cross-sectional view showing an example of an optical filter according to the present invention. [Figure 2] FIG. 2 is a cross-sectional view showing another example of an optical filter according to the present invention. [Figure 3] FIG. 3 is a cross-sectional view showing still another example of the optical filter according to the present invention. [Figure 4] FIG. 4 is a cross-sectional view showing still another example of the optical filter according to the present invention. [Figure 5] FIG. 5 shows the transmission spectrum of the first light absorber according to Example 1. [Figure 6] FIG. 6 shows the transmission spectrum of the optical filter according to the first embodiment. [Figure 7] FIG. 7 shows the transmission spectrum of the second light absorber according to Example 1. [Figure 8] FIG. 8 shows the transmission spectrum of the second light absorber according to Example 2. [Figure 9] FIG. 9 shows the transmission spectrum of the optical filter according to the second embodiment. [Figure 10] FIG. 10 shows the transmission spectrum of the laminate corresponding to the first light absorber according to Example 2. [Figure 11] FIG. 11 shows the transmission spectrum of the first light absorber according to Example 3. [Figure 12] FIG. 12 shows the transmission spectrum of the optical filter according to the third embodiment. [Figure 13] FIG. 13 shows the transmission spectrum of the second light absorber according to Example 3. [Figure 14] FIG. 14 shows the transmission spectrum of the second light absorber according to Example 4. [Figure 15] FIG. 15 shows the transmission spectrum of the optical filter according to the fourth embodiment. [Figure 16] FIG. 16 shows the transmission spectrum of the laminate corresponding to the first light absorber according to Example 4. [Figure 17] FIG. 17 shows the transmission spectrum of the optical filter according to the fifth embodiment. [Figure 18] FIG. 18 shows the transmission spectrum of the stack corresponding to the third light absorber according to Example 5. [Figure 19] FIG. 19 shows the transmission spectrum of the optical filter according to the sixth embodiment. [Figure 20]FIG. 20 shows the transmission spectrum of the stack corresponding to the third light absorber according to Example 6. [Figure 21] FIG. 21 shows the transmission spectrum of the laminate corresponding to the optical filter according to Example 7. [Figure 22] FIG. 22 shows the transmission spectrum of the stack corresponding to the third light absorber according to Example 7. [Figure 23] FIG. 23 shows the transmission spectrum of the optical filter according to the eighth embodiment. [Figure 24] FIG. 24 shows the transmission spectrum of the stack corresponding to the third light absorber according to Example 8. [Figure 25] FIG. 25 shows the transmission spectrum of the second light absorber according to Example 9. [Figure 26] FIG. 26 shows the transmission spectrum of the laminate corresponding to the first light absorber according to Example 9. [Figure 27] FIG. 27 shows the transmission spectrum of the optical filter according to the ninth embodiment. [Figure 28] FIG. 28 shows a transmission spectrum of the stack corresponding to the third light absorber according to Example 9. [Figure 29] FIG. 29 shows the transmission spectrum of the second light absorber according to Example 10. [Figure 30] FIG. 30 shows the transmission spectrum of the laminate corresponding to the first light absorber according to Example 10. [Figure 31] FIG. 31 shows the transmission spectrum of the optical filter according to the tenth embodiment. [Figure 32] FIG. 32 shows the transmission spectrum of the stack corresponding to the third light absorber according to Example 10. [Figure 33] FIG. 33 shows the transmission spectrum of the second light absorber according to Example 11. [Figure 34] FIG. 34 shows the transmission spectrum of the laminate corresponding to the first light absorber according to Example 11. [Figure 35] FIG. 35 shows the transmission spectrum of the optical filter according to the eleventh embodiment. [Figure 36]FIG. 36 shows a transmission spectrum of a stack corresponding to a third light absorber according to Example 11. [Figure 37] FIG. 37 shows the transmission spectrum of the second light absorber according to Example 12. [Figure 38] FIG. 38 shows the transmission spectrum of the laminate corresponding to the first light absorber according to Example 12. [Figure 39] FIG. 39 shows the transmission spectrum of the optical filter according to the twelfth embodiment. [Figure 40] FIG. 40 shows a transmission spectrum of a stack corresponding to a third light absorber according to Example 12. [Figure 41] FIG. 41 shows the transmission spectrum of the glass substrate used to prepare each laminate. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the following description is an example of the present invention, and the present invention is not limited to these.

[0012] Optical filters for blocking a portion of infrared or ultraviolet light can be reflective optical filters having a dielectric multilayer film, light-absorbing films or filters containing light-absorbing dyes, or hybrid filters combining these. Light-absorbing filters can be infrared-absorbing glass and light-absorbing glass, such as fluorophosphate glass or phosphate glass containing specific metal components such as Cu. In addition, light absorbers can be formed into films, sheets, or membranes from compositions obtained by dissolving or dispersing an organic dye, such as a cyanine dye compound, capable of absorbing specific light in a resin. In particular, light absorbers formed from compositions containing organic dyes and resins can be used with a variety of commercially available dye compounds with diverse light absorption properties. This facilitates adjustment or modification of optical properties and is advantageous from the standpoint of manufacturing costs. However, light-absorbing films or films formed from resins containing organic dyes may only be able to fully absorb a narrow wavelength range due to the absorption spectral characteristics of the organic dye. For this reason, for example, in order to sufficiently block infrared light in the wavelength range from 700 nm to 1000 nm, it is necessary to simultaneously use a variety of dye compounds with different absorption bands in the light-absorbing film. In addition, it may be necessary to use a light-absorbing film in combination with a light-reflecting film made of a dielectric multilayer film. The simultaneous use of a variety of dye compounds with different absorption bands in the light-absorbing film may not be advantageous from the viewpoint of sufficiently increasing the transmittance in the visible light region. The combined use of a light-absorbing film and a light-reflecting film requires laminating a large number of dielectric thin films by methods such as vacuum deposition and sputtering, which increases the manufacturing cost. Easy to do.

[0013] Therefore, the inventors of the present invention have been working day and night to develop an optical filter that can address the above-mentioned problems and exhibit the desired transmittance characteristics. After much trial and error, the inventors have discovered that an optical filter comprising a first absorber containing an organic dye and a predetermined second absorber containing a copper component can exhibit the desired transmittance characteristics. Based on this new discovery, the inventors have devised the optical filter according to the present invention.

[0014] As shown in FIGS. 1 to 4, each of the optical filters 1a, 1b, 1c, and 1d includes a first light absorber 11 and a second light absorber 12. The first light absorber 11 contains an organic dye. The second light absorber 12 contains a copper component and absorbs at least a part of infrared light. When light having a wavelength in the range of 300 nm to 1200 nm is incident on the optical filters 1a to 1d, each of the optical filters has a first transmission spectrum that satisfies the following conditions (I), (II), (III), and (IV): The first transmission spectrum is the transmission spectrum at an incident angle of 0°. (I) Average transmittance T in the wavelength range of 450 nm to 600 nm A 450-600 is over 76%. (II) a first cutoff wavelength λ, which is a wavelength exhibiting 50% transmittance in the wavelength range of 350 nm to 470 nm F exists in the range of 360nm to 450nm. (III) A wavelength that exhibits 50% transmittance in the wavelength range of 580 nm to 720 nm. Two cutoff wavelengths λ S exists in the range of 600nm to 700nm. (IV) Maximum transmittance T in the wavelength range of 700 nm to 750 nm M 700-750 is less than 5%.

[0015] When the optical filters 1a to 1d are used for digital photography in a digital camera or a smartphone built-in camera together with an imaging element such as a CCD or CMOS, the first transmission spectrum of the optical filters 1a to 1d satisfies the condition (I), and therefore the transmittance of the optical filters 1a to 1d in the visible light region is high, which is advantageous for obtaining bright images. The first transmission spectrum satisfies the conditions (II), (III), and (IV), and therefore the transmittance of the optical filters 1a to 1d in the visible light region is high, which is advantageous for obtaining bright images. This is advantageous in that it can appropriately block out light not required for forming an image, including part of the infrared ray and the light emitted from the optical filters 1a to 1d. Based on these circumstances, the optical filters 1a to 1d can exhibit desired transmittance characteristics. In addition, the optical filters 1a to 1d can exhibit desired transmittance characteristics without requiring a light-reflecting film such as a dielectric multilayer film.

[0016] Regarding condition (I), the average value T A 450-600 is preferably 78% or more.

[0017] Regarding the condition (II), the first cutoff wavelength λ F is preferably 370nm to 440nm The wavelength is preferably in the range of 380 nm to 430 nm.

[0018] Regarding the condition (III), the second cutoff wavelength λ S is preferably in the range of 620 nm to 680 nm.

[0019] Regarding condition (IV), the maximum value T M 700-750 is preferably 3% or less, and more preferably 1.5% or less.

[0020] As shown in Figs. 1 to 4, in the optical filters 1a to 1d, each of the first light absorber 11 and the second light absorber 12 can typically be formed as a film, a sheet, or a membrane. The first light absorber 11 and the second light absorber 12 are aligned in their thickness direction, and when the optical filters 1a to 1d are viewed in plan, the second light absorber 12 overlaps with at least a part of the first light absorber 11. The first transmission spectrum is a transmission spectrum obtained when light in a wavelength range of 300 nm to 1200 nm is transmitted through the first light absorber 11 and the second light absorber 12. It is Tor.

[0021] In the first transmission spectrum, the second cutoff wavelength λ S and the first cutoff wavelength λ F The absolute value of the difference ΔλS / F is, for example, 190 nm or more and 280 nm or less. The filters 1a to 1d can more reliably exhibit the desired transmittance characteristics. S / F is visible light The optical filters 1a to 1d correspond to a transmission band in the range of 1 to 3, and by specifying this within the above range, the first transmission spectrum of each of the optical filters 1a to 1d is easily adjusted to match human luminosity. Adjusting a transmission spectrum to match human luminosity means making a spectrum, in which the maximum transmittance in the transmission spectrum is set to 1 and the transmittances corresponding to other wavelengths are expressed as ratios, closer to luminosity (luminosity curve or spectral luminosity), and the higher the agreement between the two, the better the adjustment is. The output from an imaging element that receives light that has passed through an optical filter that has been well adjusted to match luminosity will also have a spectrum that is close to that corresponding to luminosity, resulting in good color reproducibility for the imaging device.

[0022] Absolute value Δλ S / F is preferably 200 nm or more and 270 nm or less, and more preferably It is between 200 nm and 260 nm.

[0023] Transmittance T at wavelength 350 nm of the first transmission spectrum 350 is, for example, 20% or less. This allows the optical filters 1a to 1d to more reliably exhibit the desired transmittance characteristics. 350 The condition that the amount of light that falls within the ultraviolet range is 20% or less is determined by the degree to which the light is blocked. This is also one of the indicators that shows whether the first transmission spectrum can be adjusted to the human visual sensitivity. 350 is preferably 16% or less.

[0024] The maximum transmittance T in the wavelength range of 750 nm to 1000 nm of the first transmission spectrum M 750-1000 is, for example, 2% or less. The desired transmittance characteristics can be reliably exhibited. In particular, light in the near-infrared region can be easily blocked, and the first transmission spectrum can be easily adjusted to match the visual sensitivity of humans.

[0025] Preferably, the maximum value T of the transmittance in the wavelength range of 750 nm to 1100 nm of the first transmission spectrum M 750-1100 is 1% or less, and more preferably, the wavelength of the first transmission spectrum Maximum transmittance T in the range of 750nm to 1200nm M 750-1200 is less than 1% .

[0026] The maximum transmittance T in the wavelength range of 800 nm to 950 nm of the first transmission spectrum M 800-950 is, for example, 1% or less. This allows the optical filters 1a to 1d to more reliably exhibit the desired transmittance characteristics. In particular, it becomes easier to further block light belonging to the near-infrared region, and the first transmission spectrum is easily adjusted to the human visual sensitivity. The maximum value T M 800-950 is preferably 0.7% or less, and more preferably 0.5% or less.

[0027] Absolute value ΔT of the difference between the maximum and minimum wavelengths that show 1% transmittance in the wavelength range of 700nm to 1200nm of the first transmission spectrum 1% is, for example, 400 nm or more. This allows the optical filters 1a to 1d to block light in the near-infrared region over a wider wavelength band, thereby more reliably achieving the desired transmittance characteristics.

[0028] The absolute value ΔT of the difference between the maximum and minimum wavelengths that exhibit a transmittance of 0.5% in the wavelength range of 700 nm to 1200 nm in the first transmission spectrum 0.5% is, for example, 400 nm or more.

[0029] The absolute value ΔT of the difference between the maximum and minimum wavelengths that exhibit a transmittance of 0.3% in the wavelength range of 700 nm to 1200 nm in the first transmission spectrum0.3% is, for example, 400 nm or more.

[0030] The transmittance characteristics of the first light absorber 11 are as follows: a first transmission spectrum of (I), (II), (III), The transmittance characteristics are not limited to specific ones as long as the conditions (i) and (iv) are satisfied. The second transmission spectrum, which is the transmission spectrum of the first light absorber 11 when light in the wavelength range of 300 nm to 1200 nm is incident on the first light absorber 11, satisfies, for example, the following conditions (i1), (i2), (i3), (i4), and (i5). By laminating and combining the first light absorber 11 that satisfies these conditions with a predetermined second light absorber, the optical filters 1a to 1d can exhibit desired transmittance characteristics. The second transmission spectrum is the transmission spectrum at an incident angle of 0°. (i1) Wavelength λ at which the transmittance is minimum in the wavelength range of 550 nm to 850 nm (2)M is between 650 nm and 770 nm. (i2) The minimum wavelength λ at which 70% transmittance is exhibited in the wavelength range of 550 nm to 850 nm (2) 70%L is 570 nm or more and 670 nm or less. (i3) The minimum wavelength λ at which 50% transmittance is exhibited in the wavelength range of 550 nm to 850 nm (2) 50%L is 590 nm or more and 700 nm or less. (i4) The minimum wavelength λ at which 20% transmittance is exhibited in the wavelength range of 550 nm to 850 nm (2) 20%L is between 630 nm and 720 nm. (i5) Average transmittance T in the wavelength range of 450 nm to 600 nm (2)A 450-600 76 % or more.

[0031] Regarding condition (i1), the wavelength λ (2)M is preferably 650 nm or more and 750 nm or less.

[0032] Regarding condition (i2), the minimum value λ (2)70%L is preferably between 590 nm and 660 nm. be.

[0033] Regarding condition (i3), the minimum value λ (2) 50%L is preferably between 580nm and 690nm be.

[0034] Regarding condition (i4), the minimum value λ (2) 20%L is preferably between 640 nm and 710 nm. be.

[0035] Regarding condition (i5), the average value T (2)A 450-600 is preferably 80% or more, and more preferably Or more than 85%.

[0036] The second transmission spectrum may satisfy at least one of the following conditions (i6), (i7), and (i8), which allows the optical filters 1a to 1d to more reliably exhibit the desired transmittance characteristics. (i6) The maximum wavelength λ at which 70% transmittance is exhibited in the wavelength range of 550 nm to 850 nm (2) 70%H and the minimum value λ (2) 70%L The absolute value of the difference Δλ (2) 70% is 120 nm or more and 250 nm or less. (i7) The maximum wavelength λ at which 50% transmittance is exhibited in the wavelength range of 550 nm to 850 nm (2) 50%H and the minimum value λ (2) 50%L The absolute value of the difference Δλ (2) 50% is 70 nm or more and 210 nm or less. (i8) The maximum wavelength λ at which a transmittance of 20% is exhibited in the wavelength range of 550 nm to 850 nm (2) 20%H and the minimum value λ (2) 20%L The absolute value of the difference Δλ (2)20% is 30 nm or more and 160 nm or less.

[0037] The second transmission spectrum preferably satisfies conditions (i6), (i7), and (i8) above.

[0038] Regarding condition (i6), the absolute value Δλ (2) 70% is preferably between 130 nm and 240 nm. and more preferably, 140 nm or more and 230 nm or less.

[0039] Regarding condition (i7), the absolute value Δλ (2) 50% is preferably 80 nm or more and 200 nm or less, and more preferably 90 nm or more and 190 nm or less.

[0040] Regarding condition (i8), the absolute value Δλ (2) 20% is preferably 40 nm or more and 150 nm or less, and more preferably 50 nm or more and 140 nm or less.

[0041] The second transmission spectrum is, for example, −1.2 [% / nm]≦(20−70) / (λ (2) 20%L -λ (2) 70%L By combining the first light absorber 11 that satisfies this condition with the second light absorber, the optical filters 1a to 1d can exhibit the desired transmission spectrum. (2) 20%L -λ (2) 70%L ) [% / nm] is the wavelength λ (2) 70%L [nm] and λ (2) 20%L represents the average slope of the second transmission spectrum in the range of [nm] and ΔT (2) / Δλ (2) L It can also be expressed as:

[0042] Minimum value λ (2)20%L and the minimum value λ (2) 70%L is preferably -1.1 [% / nm] ≦ (20-70) / (λ (2) 20%L -λ (2) 70%L )≦-0.7[% / nm], and more preferably, -1.0[% / nm]≦(20-70) / (λ (2) 20%L -λ (2) 70%L )≦-0.75[% / nm].

[0043] The organic dye contained in the first light absorber 11 is made of an organic compound, and is not clearly distinguished as a dye or a pigment here, and is not limited to a specific organic dye, and the organic dye contained in the first light absorber 11 includes, for example, at least one selected from the group consisting of cyanine dyes, squarylium dyes, phthalocyanine dyes, diimmonium dyes, and azo dyes. This makes it easy for the optical filters 1a to 1d to exhibit desired transmittance characteristics.

[0044] The first light absorber 11 may contain a single type of organic dye or may contain multiple types of organic dyes. The organic dye has a maximum absorption wavelength in the wavelength range of 650 nm to 800 nm, for example.

[0045] The first light absorber 11 further includes, for example, a matrix. The organic dye is typically dispersed or dissolved in the matrix. The matrix is not limited to a specific material as long as the first transmission spectrum satisfies the conditions (I), (II), (III), and (IV). The matrix contained in the first light absorber 11 is typically a material that has high transmittance in the wavelength range of 400 nm to 600 nm. For example, when a layer having a thickness of 0.1 mm is formed using only this material, the transmittance of the layer in the wavelength range of 400 nm to 600 nm is, for example, 70% or more, preferably 75% or more, more preferably 80% or more, and even more preferably 85% or more.

[0046] The material of the matrix contained in the first light absorber 11 is, for example, a resin. The type of resin contained in the first light absorber 11 is not limited to a specific type. The resin is, for example, a cyclic polyolefin resin, an epoxy resin, a polyimide resin, a modified acrylic resin, a silicone resin, or a polyvinyl resin such as PVB. The resin may be a curable resin that can be cured by energy irradiation such as heat or light. The matrix contained in the first light absorber 11 may be an organic-inorganic hybrid material or an inorganic material formed by hydrolyzing and condensation-polymerizing an alkoxide containing a metal component according to a sol-gel method.

[0047] The first light absorber 11 may be formed as a layer on the surface of, for example, a substrate, an optical device, or an optical component. The substrate may be made of a transparent material such as glass, resin, or crystal.

[0048] The thickness of the first light absorber 11 is, for example, 0.5 μm to 1000 μm, may be 1 μm to 250 μm, or may be 1 μm to 200 μm.

[0049] The transmittance characteristics of the second light absorber 12 are as follows: the first transmission spectrum is (I), (II), (III), The second light absorber 12 is not limited to a specific transmittance characteristic as long as it satisfies the conditions (ii) and (iv). The third transmission spectrum, which is the transmission spectrum of the second light absorber 12 when light in the wavelength range of 300 nm to 1200 nm is incident on the second light absorber 12, satisfies, for example, the following conditions (ii1), (ii2), (ii3), (ii4), and (ii5). The second light absorber 12 satisfying these conditions and the above-mentioned By combining with the first light absorber, the optical filters 1a to 1d tend to exhibit desired transmittance characteristics. The third transmission spectrum is a transmission spectrum at an incident angle of 0°. (ii1) Wavelength λ showing 70% transmittance in the wavelength range of 550 nm to 750 nm (3) 70%H is 620 nm or more and 690 nm or less. (ii2) Wavelength λ showing 50% transmittance in the wavelength range of 550 nm to 750 nm (3) 50%H is between 640 nm and 720 nm. (ii3) Wavelength λ showing 20% transmittance in the wavelength range of 550 nm to 750 nm (3) 20%H is between 670 nm and 750 nm. (ii4) Transmittance T at a wavelength of 750 nm (3) 750 is between 0.5% and 6%. (ii5) Average transmittance T in the wavelength range of 450 nm to 600 nm (3)A 450-600 is over 76%.

[0050] Regarding the condition (ii1), the wavelength λ (3) 70%H is preferably 630 nm or more and 680 nm or less.

[0051] Regarding the condition (ii2), the wavelength λ (3) 50%H is preferably 650 nm or more and 710 nm or less.

[0052] Regarding the condition (ii3), the wavelength λ (3) 20%H is preferably 680 nm or more and 740 nm or less.

[0053] Regarding the condition (ii4), the transmittance T (3) 750 is preferably 1% or more and 5% or less.

[0054] Regarding the condition (ii5), the average value T (3)A 450-600 is preferably 78% or more, and more preferably 80% or more.

[0055] The maximum transmittance T in the wavelength range of 750 nm to 1100 nm of the third transmission spectrum (3)M 750-1100is, for example, 0.5% or more and 6% or less. This allows the optical filters 1a to 1d to easily exhibit the desired transmittance characteristics. (3)M 750-1100 is preferably 1% or more and 5% or less.

[0056] In the third transmission spectrum, the wavelength λ (3) 20%H , wavelength λ (3) 70%H , and transmittance T (3) 750 For example, -0.9[% / nm]≦(20-70) / (λ (3) 20%H -λ (3) 70%H )≦-0.78[% / nm] and -0.9[% / nm]≦(T (3) 750 -70) / (750-λ (3) 70%H )≦-0.5[% / nm]. By combining the second light absorber 12, which satisfies the above-mentioned condition, with the first light absorber, the optical filters 1a to 1d are more likely to exhibit the desired transmission spectrum. (3) 20%H -λ (3) 70%H ) [% / nm] is the wavelength λ (3) 70%H [nm] and λ (3) 20%H [nm] represents the average slope of the third transmission spectrum in the range of ΔT (3) / Δλ (3) H It can also be expressed as (T (3) 750 -70) / (750-λ (3) 70%H ) [% / nm] is the wavelength of 750 nm and λ (3) 70%H [ nm] and represents the average slope of the third transmission spectrum in the range of ΔT (3) / Δλ (3) 750 It can also be expressed as:

[0057] In the third transmission spectrum, the wavelength λ (3) 20%H and wavelength λ (3) 70%H is preferably -0.88[% / nm]≦(20-70) / (λ (3) 20%H -λ (3) 70%H )≦-0.80[% / nm], and more preferably, -0.87[% / nm]≦(20-70) / (λ (3) 20%H -λ (3) 70%H )≦-0.82[% / nm].

[0058] In the third transmission spectrum, the wavelength λ (3) 70%H and transmittance T (3) 750 is preferably -0 .85[% / nm]≦(T (3) 750 -70) / (750-λ (3) 70%H )≦-0.55[% / nm], and more preferably -0.8[% / nm]≦(T (3) 750 -70) / (750-λ (3) 70%H )≦-0.6[% / nm].

[0059] The third transmission spectrum satisfies at least the following conditions (ii6), (ii7), and (ii8): This allows the optical filters 1a to 1d to easily exhibit desired transmittance characteristics. (ii6) Wavelength λ showing 70% transmittance in the wavelength range of 300 nm to 450 nm (3) 70%L is 360 nm or more and 430 nm or less. (ii7) Wavelength λ showing 50% transmittance in the wavelength range of 300 nm to 450 nm (3) 50%L is 340 nm or more and 390 nm or less. (ii8) Wavelength λ showing 20% transmittance in the wavelength range of 300 nm to 450 nm (3) 20%L is 330 nm or more and 380 nm or less.

[0060] wavelength λ (3) 70%L is preferably 370 nm or more and 420 nm or less.

[0061] wavelength λ (3) 50%L is preferably 350 nm or more and 380 nm or less.

[0062] wavelength λ (3) 20%L is preferably 340 nm or more and 360 nm or less.

[0063] In the third transmission spectrum, the wavelength λ (3) 70%L and wavelength λ (3) 20%L For example, 0.75[% / nm]≦(70-20) / (λ (3) 70%L -λ (3) 20%L )≦1.6[% / nm]. This makes it easy for the optical filters 1a to 1d to adjust the transmission spectrum in the ultraviolet range and to exhibit the desired transmittance characteristics. (3) 70%L -λ (3) 20%L ) [% / nm] is λ (3) 20%L [nm] and wavelength λ (3) 70%L [nm] represents the average slope of the third transmission spectrum in the range of ΔT (3) / Δλ (3) L It can also be expressed as:

[0064] wavelength λ (3) 70%L and wavelength λ (3) 20%L is preferably 0.85 [% / nm]≦(70−20) / (λ (3) 70%L-λ (3) 20%L )≦1.55[% / nm], and more preferably, 0.9[% / nm]≦(70-20) / (λ (3) 70%L -λ (3) 20%L )≦1.5[% / nm].

[0065] In the third transmission spectrum, the wavelength λ (3) 50%H and wavelength λ (3) 50%L The absolute value of the difference Δλ (3) 50% is, for example, 270 nm or more and 350 nm or less. This ensures a wide band with high transmittance in the wavelength range corresponding to the visible light range, making it easier for the optical filters 1a to 1d to exhibit desired transmittance characteristics.

[0066] Absolute value Δλ (3) 50% is preferably 290 nm or more and 340 nm or less.

[0067] As long as the first transmission spectrum satisfies conditions (I), (II), (III), and (IV), The manner in which the copper component is contained in the second light absorber 12 is not limited to a specific embodiment. The substrate 12 contains, for example, a compound containing a copper component and at least one selected from the group consisting of phosphonic acid, sulfonic acid, and carboxylic acid. These compounds are light-absorbing compounds that have light-absorbing properties mainly due to the action of the copper component, and these properties contribute to achieving the desired transmission spectrum of the optical filter of the present invention, making it easier for the optical filters 1a to 1d to more reliably exhibit the desired transmittance characteristics.

[0068] In the second light absorber 12, the light absorbing compound may be a complex formed of a copper component and at least one selected from the group consisting of phosphonic acid, sulfonic acid, and carboxylic acid. The light absorbing compound may be fine particles containing a copper component and phosphonic acid. In this case, the phosphonic acid is not limited to a specific phosphonic acid. The phosphonic acid may be represented, for example, by the following formula (a):

[0069] [ka] [In the formula, R 11 is an alkyl group, an aryl group, a nitroaryl group, a hydroxyaryl group, or a halogenated aryl group in which at least one hydrogen atom in the aryl group is substituted with a halogen atom.

[0070] In formula (a), the alkyl group has, for example, 8 or less carbon atoms, and the aryl group is, for example, a phenyl group, a benzyl group, or a toluyl group.

[0071] In forming the second light absorber 12, the copper component is provided as, for example, a copper salt. The copper salt may be an anhydrate or hydrate of copper chloride, copper formate, copper stearate, copper benzoate, copper pyrophosphate, copper naphthenate, and copper citrate. For example, copper acetate monohydrate is Cu(CH3 COO)2·H2O, and one mole of copper acetate monohydrate provides one mole of copper ions.

[0072] The second light absorber 12 further includes, for example, a matrix. The light absorbing compound containing a copper component is typically dispersed in the matrix. This matrix is not limited to a specific material as long as the first transmission spectrum satisfies the conditions (I), (II), (III), and (IV). The matrix contained in the second light absorber 12 is typically a material that has high transmittance in the wavelength range of 400 nm to 600 nm. For example, when a layer having a thickness of 0.1 mm is formed using only that material, the transmittance of that layer in the wavelength range of 400 nm to 600 nm is, for example, 70% or more, preferably 75% or more, more preferably 80% or more, and even more preferably 85% or more.

[0073] The material of the matrix contained in the second light absorber 12 is, for example, a resin. The type of resin contained in the second light absorber 12 is not limited to a specific type. The resin is, for example, a cyclic polyolefin resin, an epoxy resin, a polyimide resin, a modified acrylic resin, a silicone resin, or a polyvinyl resin such as PVB. The resin may be a curable resin that can be cured by energy irradiation such as heat or light. The matrix contained in the second light absorber 12 may be an organic-inorganic hybrid material or an inorganic material formed by hydrolyzing and condensation-polymerizing an alkoxide containing a metal component according to a sol-gel method.

[0074] The second light absorber 12 may be, for example, a phosphoric acid ester, a metal alkoxide, a hydrolysis condensation product of a metal alkoxide, a silicon alkoxide, or a hydrolysis condensation product of a silicon alkoxide. The second light absorber 12 may further contain at least one selected from the group consisting of:

[0044] This makes it easier for the compound containing a copper component to be uniformly dispersed in the second light absorber 12. The second light absorber 12 may contain a mixture of at least two selected from this group. For example, a phosphate ester, a metal alkoxide, or a silicon alkoxide is mixed with a copper component and a component such as phosphonic acid in preparing a liquid composition for the second light absorber 12. In this case, a portion of the phosphate ester, the metal alkoxide, and the silicon alkoxide may be contained in the fine particles containing a copper component due to an interaction with the copper component or a component such as phosphonic acid or a compound containing these in preparing the liquid composition for the second light absorber 12.

[0075] The phosphate ester contained in the second light absorber 12 is not limited to a specific phosphate ester. The phosphate ester has, for example, a polyoxyalkyl group. Examples of such phosphate esters include Plysurf A208N: polyoxyethylene alkyl (C12, C13) ether phosphate ester, Plysurf A208F: polyoxyethylene alkyl (C8) ether phosphate ester, Plysurf A208B: polyoxyethylene lauryl ether phosphate ester, Plysurf A219B: polyoxyethylene lauryl ether phosphate ester, Plysurf AL: polyoxyethylene styrenated phenyl ether phosphate ester, Plysurf A212C: polyoxyethylene tridecyl ether phosphate ester, and Plysurf A215C: polyoxyethylene tridecyl ether phosphate ester. All of these are products manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd. In addition, examples of phosphate esters include NIKKOL DDP-2: polyoxyethylene alkyl ether phosphate ester, NIKKOL DDP-4: polyoxyethylene alkyl ether phosphate ester, and NIKKOL DDP-6: polyoxyethylene alkyl ether phosphate ester. All of these are products manufactured by Nikko Chemicals Co., Ltd.

[0076] The metal alkoxide contained in the second light absorber 12 or the metal alkoxide that forms the hydrolysis condensate of the metal alkoxide is, for example, an alkoxide of at least one metal selected from the group consisting of Li, Na, Mg, Ca, Sr, Ba, Ge, Sn, Pb, Al, Ga, In, Tl, Zn, Cd, Cu, Ag, Au, Ni, Pd, Pt, Co, Rh, Ir, Fe, Mn, Cr, Mo, W, V, Nb, Ta, Ti, and Zr.

[0077] These metal alkoxides contribute to accelerating the curing reaction of the resin contained in the second light absorber 12. The amount of the component is preferably approximately 0.1 to 10 mass % relative to the resin, more preferably 0.1 to 3 mass %. The high reactivity of metal alkoxides added at such a ratio promotes the formation of a resin skeleton, enabling the formation of a dense, rigid absorbing film, and particularly contributes significantly to increasing the inclusion of copper compounds in the film. By forming the second light absorber 12 into such a film, defects that occur in adjacent portions when other absorbing films are laminated thereon can be suppressed. This suppresses undesirable effects, such as the copper component in the second light absorber reacting with the organic dye in the first light absorber 11, altering the organic dye and reducing its light absorption ability, thereby achieving desired optical properties.

[0078] As shown in Figures 1 and 3, the second light absorber 12 is formed in the form of a layer on the surface of the first light absorber 11 formed as a sheet or film, for example. As shown in Figures 2 and 4, the second light absorber 12 may be formed as a sheet or film. The second light absorber 12 may be formed as a layer on the surface of a substrate, an optical device, or an optical component. The substrate may be formed of a transparent material such as glass, resin, or crystal, for example.

[0079] The thickness of the second light absorber 12 is, for example, 20 μm to 1000 μm, may be 50 μm to 500 μm, or may be 65 μm to 350 μm.

[0080] In the second and third transmission spectra, λ is preferably expressed as (2) 50%L <λ (3) 50%H <λ (2) 50%H The condition, λ (2) 70%L <λ (3) 70%H Conditions, and and λ (2) 20%L <λ (3) 20%HThis satisfies the above condition. As a result, the optical filters 1a to 1d can more reliably exhibit the desired transmittance characteristics. Specifically, in the first transmission spectrum of the optical filter, the second cutoff wavelength is likely to depend on the characteristics including the transmission spectrum of the first absorber.

[0081] In the second transmission spectrum and the third transmission spectrum, more preferably, λ (3) 50%H - λ (2) 50%L The condition that the value of λ is 5 nm or more and 70 nm or less, and (2) 50%H -λ (3) 50%H of The condition that the value is 50 nm or more and 150 nm or less is further satisfied. This makes it easier for the optical filters 1a to 1d to exhibit the desired transmittance characteristics more reliably. In this case, λ (3) 50%H -λ (2) 50%L The value of is preferably 15 nm or more and 60 nm or less, and λ (2) 50%H -λ (3) 50%H The value is preferably 70 nm or more and 125 nm or less.

[0082] In the second and third transmission spectra, |{(20-70) / (λ (3) 20%H -λ (3) 70%H )}-{(20-70) / (λ (2) 20%L -λ (2) 70%L )}| is, for example, not less than 0 and not more than 0.10, and preferably not less than 0 and not more than 0.07. This makes it easier for the optical filters 1a to 1d to exhibit the desired transmittance characteristics more reliably.

[0083] In the second transmission spectrum and the third transmission spectrum, preferably λ (3) 20%H -λ (3)70%H <Δλ (2) 50% The condition is satisfied, and more preferably 2×(λ (3) 20%H -λ (3) 70%H )<Δλ (2) 50% This satisfies the above condition, and the optical filters 1a to 1d can more reliably exhibit the desired transmittance characteristics.

[0084] In the second transmission spectrum and the third transmission spectrum, preferably, the maximum value λ (2) 20%H is 750 nm or more, and λ = λ (2) 70%H Transmittance in the third transmission spectrum at T (3) λ(2)70%H is 5% or less. This allows the optical filters 1a to 1d to more reliably exhibit the desired transmittance characteristics. (3) λ(2)70%H is more preferably 1% or less. (2) 50%H Transmittance T at (3) λ(2)50%H For example, For example, it is less than 1%.

[0085] 3 and 4, the optical filters 1c and 1d further include, for example, a third light absorber 13. The third light absorber 13 contains an ultraviolet absorber. A fourth transmission spectrum, which is the transmission spectrum of the third light absorber 13 when light having a wavelength in the range of 300 nm to 1200 nm is incident on the third light absorber 13, satisfies the following conditions (iii1), (iii2), and (iii3). This makes it easy for the optical filters 1c and 1d to exhibit desired transmittance characteristics. The fourth transmission spectrum is a transmission spectrum at an incident angle of 0°. (iii1) Wavelength λ showing 70% transmittance in the wavelength range of 300 nm to 450 nm (4) 70%L is 350 nm or more and 450 nm or less. (iii2) Wavelength λ showing 50% transmittance in the wavelength range of 300 nm to 450 nm (4) 50%L is 340 nm or more and 440 nm or less. (iii3) Wavelength λ showing 20% transmittance in the wavelength range of 300 nm to 450 nm (4) 20%L is 340 nm or more and 440 nm or less.

[0086] In the optical filters 1c and 1d, the transmittance T at a wavelength of 350 nm of the first transmission spectrum 350 is preferably 1% or less, and more preferably 0.5% or less.

[0087] In the fourth transmission spectrum, the wavelength λ (4) 70%L and wavelength λ (4) 20%L For example, 3.0 [% / nm] ≦ (70-20) / (λ (4) 70%L -λ (4) 20%L )≦4.2 [% / nm] is satisfied. This makes it easier for the optical filters 1c and 1d to exhibit the desired transmittance characteristics. (70-20) / (λ (4) 70%L -λ (4) 20%L ) is λ (4) 20%L [nm] and wavelength λ (4) 70%L [nm] represents the average slope of the third transmission spectrum in the range of ΔT (4) / Δλ (4) L and Also represents.

[0088] wavelength λ (4) 70%L and wavelength λ (4) 20%L is preferably 3.1 [% / nm] ≦ (70-20) / (λ (4) 70%L -λ (4) 20%L)≦4.1[% / nm], and more preferably 3.3[% / nm]≦(70-20) / (λ (4) 70%L -λ (4) 20%L )≦4.0 [% / nm] is satisfied. This makes it easier for the optical filters 1c and 1d to exhibit the desired transmittance characteristics.

[0089] There is no particular limitation on the type of ultraviolet absorber contained in the third light absorber 13. The ultraviolet absorber includes, for example, at least one selected from the group consisting of benzophenone-based compounds, benzotriazole-based compounds, triazine-based compounds, acrylonitrile-based compounds, and salicylic acid-based compounds.

[0090] The ultraviolet absorber is 2-hydroxybenzophenone, 2,4-dioxybenzophenone, 2-oxy-4-methoxybenzophenone, 2,2'4,4'-tetraoxybenzophenone, 2,2'-dioxy-4,4'-dimethoxybenzophenone, 2-oxy-4-methoxy-4'-chlorobenzophenone, 2-oxy-4-n-octoxybenzophenone, 2,4-dioloxybenzophenone, 2-oxy-4-methoxy-2'-carboxybenzophenone, 2,2'-dioxy-4-n-octoxybenzophenone, 2-oxy-5-chlorobenzophenone, The solvent may contain at least one selected from the group consisting of benzophenone, 2,4-dibenzoylresorcinol, 2(2'-oxy-5'-methylphenyl)benzotriazole, 2(2'-oxy-3',5'-dibutylphenyl)-6-chlorobenzotriazole, resorcinol monobenzoate, phenyl salicylate, 4-t-butylphenyl salicylate, p-octylphenyl salicylate, ethyl diphenylmethylenecyanate, 2-ethylhexyl diphenylmethylenecyanate, and 2-oxyphenyl-1,3,5-triazine.

[0091] The third light absorber 13 further includes, for example, a matrix. The ultraviolet absorber is typically dispersed in the matrix. This matrix is not limited to a specific material as long as the first transmission spectrum satisfies the conditions (I), (II), (III), and (IV). The matrix contained in the light absorber 13 is typically a material that has high transmittance at wavelengths of 400 nm to 600 nm. For example, when a layer having a thickness of 0.1 mm is formed using only that material, the transmittance of that layer at wavelengths of 400 nm to 600 nm is, for example, 70% or more, preferably 75% or more, more preferably 80% or more, and even more preferably 85% or more.

[0092] The matrix contained in the third light absorber 13 is, for example, a resin. The type of resin contained in the third light absorber 13 is not limited to a specific type. The resin is, for example, a cyclic polyolefin resin, an epoxy resin, a polyimide resin, a modified acrylic resin, a silicone resin, or a polyvinyl resin such as PVB. The resin may be a curable resin that can be cured by energy irradiation such as heat or light. The matrix contained in the third light absorber 13 may be an organic-inorganic hybrid material or an inorganic material formed by hydrolyzing and condensation-polymerizing an alkoxide containing a metal component according to a sol-gel method.

[0093] The third light absorber 13 can typically be formed as a film, a sheet, or a membrane. The third light absorber 13 is formed, for example, in the form of a layer on the surface of the first light absorber 11 or the second light absorber 12, which are formed as a film or a sheet. The third light absorber 13 may be formed as a sheet or a film.

[0094] The thickness of the third light absorber 13 is, for example, 2 μm to 250 μm, and may be 5 μm to 200 μm, 10 μm to 200 μm, or 15 μm to 100 μm.

[0095] In the third transmission spectrum and the fourth transmission spectrum, for example, λ (3)50%L <λ (4) 50%L The condition is satisfied. (3) 50%L +5nm<λ (4) 50%L and more preferably, λ (3) 50%L +10nm<λ (4) 50%L This makes it easier for the optical filters 1c and 1d to exhibit the desired transmittance characteristics.

[0096] In the third transmission spectrum and the fourth transmission spectrum, for example, λ (3) 20%L <λ (4) 20%L The condition is satisfied. (3) 20%L +5nm<λ (4) 20%L and more preferably, λ (3) 20%L +10nm<λ (4) 20%L This makes it easier for the optical filters 1c and 1d to exhibit the desired transmittance characteristics.

[0097] In the third transmission spectrum and the fourth transmission spectrum, it is preferable that (3) 70%L -λ (3) 20%L )<(70-20) / (λ (4) 70%L -λ (4) 20%L ) is satisfied, and more preferably 2.5×(70-20) / (λ (3) 70%L -λ (3) 20%L )<(70-20) / (λ (4) 70%L -λ (4) 20%L ) is satisfied. This makes it easier for the optical filters 1c and 1d to exhibit the desired transmittance characteristics.

[0098] An example of a manufacturing method for optical filters 1a to 1d will be described. As shown in FIG. 1, in optical filters 1a and 1c, the first light absorber 11 is, for example, a film. The first light absorber 11 can be formed, for example, by applying a composition containing an organic dye and matrix raw materials onto a predetermined substrate to form a coating film, and then curing the coating film by a treatment such as drying or heating. The first light absorber 11 formed on the substrate is, for example, peeled from the substrate. Meanwhile, the second light absorber 12 can be formed by applying a composition containing a copper component and matrix raw materials onto the surface of the first light absorber 11 to form a coating film, and then curing the coating film by a treatment such as drying or heating. In this manner, the optical filter 1a can be produced. Thereafter, a composition containing an ultraviolet absorber and matrix raw materials can be applied to another surface of the first light absorber 11, and then cured by a treatment such as drying or heating, to form the third light absorber 13. In this manner, the optical filter 1c can be produced.

[0099] As shown in FIG. 2, in optical filters 1b and 1d, the second light absorber 12 is, for example, a film. The second light absorber 12 can be formed, for example, by applying a composition containing a copper component and matrix raw materials to a predetermined substrate to form a coating film, and then curing the coating film by a treatment such as heating. The second light absorber 12 formed on the substrate is then peeled off from the substrate. Meanwhile, the first light absorber 11 can be formed by applying a composition containing an organic dye and matrix raw materials to the surface of the second light absorber 12 to form a coating film, and then curing the coating film by a treatment such as drying or heating. In this manner, optical filter 1b can be produced. Then, a composition containing an ultraviolet absorber and matrix raw materials can be applied to another surface of the second light absorber 12, and then cured by a treatment such as drying or heating, to form the third light absorber 13. In this manner, optical filter 1d can be produced. [Example]

[0100] The present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples.

[0101] In each example, a first light absorber, a second light absorber, an optical filter, a laminate corresponding to the first light absorber, a second light absorber, an optical filter, a laminate corresponding to the first light absorber, a second light absorber, an ultraviolet-visible-near-infrared spectrophotometer V-670 manufactured by JASCO Corporation, The transmission spectrum of the laminate corresponding to the first light absorber or the laminate corresponding to the third light absorber was measured at an incident angle of 0°.

[0102] Example 1 An organic dye having an absorption maximum wavelength in the range of 660 nm to 770 nm was mixed with methyl ethyl ketone (MEK) as a solvent and polyvinyl butyral (PVB), and the mixture was stirred for 2 hours to obtain a liquid composition H1. The organic dye was soluble in MEK and had low absorption in the visible range. The organic dye contained at least one selected from the group consisting of cyanine dye compounds, squarylium dye compounds, phthalocyanine dye compounds, diimmonium dye compounds, and azo dye compounds. The solid content of the PVB was 99% by weight.

[0103] 4.500 g of copper acetate monohydrate and 240 g of tetrahydrofuran (THF) were mixed, and the mixture was stirred for 3 hours to obtain a copper acetate solution. Next, 2.572 g of Plysurf A208F, a phosphate ester compound manufactured by Daiichi Kogyo Seiyaku Co., Ltd., was added to the resulting copper acetate solution and stirred for 30 minutes to obtain Solution A. 40 g of THF was added to 2.886 g of n-butylphosphonic acid and stirred for 30 minutes to obtain Solution B. While stirring Solution A, Solution B was added to Solution A and stirred at room temperature for 1 minute. Next, 100 g of toluene was added to this solution and stirred at room temperature for 1 minute to obtain Solution C. Solution C was placed in a flask and heated in an oil bath (Tokyo Rikakikai Co., Ltd., Model: OSB-2100) while undergoing a solvent removal treatment using a rotary evaporator (Tokyo Rikakikai Co., Ltd., Model: N-1110SF). The oil bath temperature was adjusted to 105°C. After the solvent removal treatment, the liquid D was removed from the flask. The fine particles were well dispersed in the liquid D, and the fine particles contained a copper complex. The copper complex contained a compound formed by the reaction of phosphonic acid with a copper component. Next, 8.91 g of a curable silicone resin (manufactured by Shin-Etsu Chemical Co., Ltd., product name: KR-300) and 0.09 g of an aluminum alkoxide compound (manufactured by Shin-Etsu Chemical Co., Ltd., product name: CAT-AC) were added to the liquid D and stirred for 30 minutes. In this way, a liquid composition E1 containing a curable resin and fine particles containing a copper complex was obtained.

[0104] Liquid composition H1 was applied to an area of approximately 76 mm x 76 mm on the surface of a glass substrate (D263 T eco, manufactured by SCHOTT) using a dispenser to form a coating film. After this coating film was thoroughly dried at room temperature, it was placed in an oven and heated at 130°C for 1 hour to cure liquid composition H1. A fluorine-containing antifouling coating was previously applied to the surface of the glass substrate. Optool DSX, manufactured by Daikin Industries, Ltd., was used for the antifouling coating. A coating liquid containing Optool DSX was applied to the surface of the glass substrate to form a coating film, which was then dried to form the antifouling coating. The cured product of liquid composition H1 was peeled off from the glass substrate to obtain a first light absorber according to Example 1. The thickness of the first light absorber was measured using a micrometer and found to be 110 μm. The transmission spectrum of the first light absorber according to Example 1 is shown in FIG. 5, and the characteristic values of this transmission spectrum are shown in Table 2.

[0105] The liquid composition E1 was applied to the surface of the first light absorber according to Example 1 using a dispenser to form a coating film, and the coating film was thoroughly dried at room temperature. Thereafter, the first light absorber according to Example 1 was placed in an oven and heat-treated under conditions of 45°C for 2 hours, 85°C for 3 hours, 125°C for 1 hour, and 150°C for 1 hour to harden the coating film, thereby forming a second light absorber according to Example 1 on the first light absorber. The thickness of the second light absorber was 160 μm. In this manner, an optical filter according to Example 1 was obtained. The transmission spectrum of the optical filter according to Example 1 is shown in FIG. 6, and the characteristic values of this transmission spectrum are shown in Table 1.

[0106] The liquid composition E1 was applied by a dispenser to the surface of a glass substrate having an antifouling coating containing a fluorine component to form a coating film, and this coating film was used in the production of the optical filter according to Example 1. The coating film of liquid composition E1 was dried and heated under the same conditions as those for the coating film of liquid composition E1 in Example 1 to be cured. The cured coating film of liquid composition E1 was peeled off from the glass substrate to obtain a sample for a secondary light absorber according to Example 1. The application conditions for liquid composition E1 were adjusted so that the thickness of the sample for a secondary light absorber according to Example 1 would be approximately the same as the thickness of the second light absorber in the optical filter according to Example 1. The transmission spectrum of the sample for a secondary light absorber according to Example 1 is shown in FIG. 7, and the characteristic values of this transmission spectrum and the like are shown in Table 3. The transmission spectrum of the sample for a secondary light absorber according to Example 1 can be considered to be the transmission spectrum of the second light absorber of the optical filter according to Example 1.

[0107] <Example 2> Liquid composition E1 was applied using a dispenser to an area of approximately 76 mm x 76 mm on the surface of a glass substrate having an antifouling coating containing a fluorine component, forming a coating film. The coating film was thoroughly dried at room temperature and then placed in an oven and cured by heat treatment at 45°C for 2 hours, 85°C for 3 hours, 125°C for 1 hour, and 150°C for 1 hour. The cured coating film of liquid composition E1 was peeled from the glass substrate to obtain a second light absorber according to Example 2. The thickness of the second light absorber according to Example 2 was measured using a micrometer and found to be 141 μm. The transmission spectrum of the second light absorber according to Example 2 is shown in FIG. 8, and the characteristic values of the transmission spectrum are shown in Table 3.

[0108] Liquid composition H2 was prepared in the same manner as liquid composition H1, except for the following points. The organic dye contained in liquid composition H2 was the same as the organic dye contained in liquid composition H1, but the concentration of the organic dye in liquid composition H2 was higher than the concentration of the organic dye in liquid composition H1. The solid content of the PVB was 99 wt%.

[0109] The liquid composition H2 was applied to the surface of the second light absorber according to Example 2 using a dispenser to form a coating film. After this coating film was thoroughly dried at room temperature, it was placed in an oven and subjected to a heat treatment at 130°C for 1 hour to be cured. In this way, the first light absorber according to Example 2 was formed on the second light absorber according to Example 2. The thickness of the first light absorber according to Example 2 was 4 μm. In this way, an optical filter according to Example 2 was obtained. The transmission spectrum of the optical filter according to Example 2 is shown in FIG. 9, and the characteristic values of this transmission spectrum and the like are shown in Table 1.

[0110] Liquid composition H2 was applied to the surface of a glass substrate using a dispenser to form a coating film. This coating film was cured under the same conditions as the coating film of liquid composition H2 in the production of the optical filter according to Example 2, to obtain a laminate 2-I corresponding to the first light absorber of the optical filter according to Example 2. The application conditions for liquid composition H2 were adjusted so that the thickness of the cured product of the coating film of liquid composition H2 in laminate 2-I was approximately the same as the thickness of the first light absorber according to Example 2. The transmission spectrum of laminate 2-I is shown in FIG. 10, and the characteristic values of this transmission spectrum are shown in Table 2.

[0111] Example 3 Liquid composition H3 was prepared in the same manner as liquid composition H1, except for the following points. The organic dye contained in liquid composition H3 was the same as the organic dye contained in liquid composition H1, but the concentration of the organic dye in liquid composition H3 was adjusted to be slightly lower than the concentration of the organic dye in liquid composition H1. The solid content of the PVB was 99 wt%.

[0112] Liquid composition H3 was applied with a dispenser to an area of approximately 76 mm x 76 mm on the surface of a glass substrate having an antifouling coating containing a fluorine component, to form a coating film. After this coating film was thoroughly dried at room temperature, it was placed in an oven and subjected to a heat treatment at 130°C for 1 hour to harden the coating film. The cured coating film of liquid composition H3 was peeled off from the glass substrate to obtain a first light absorber according to Example 3. When the thickness of the first light absorber according to Example 3 was measured using a micrometer, it was found to be 160 µm. The transmission spectrum of the first light absorber according to Example 3 The transmission spectrum is shown in Figure 11, and the characteristic values of the transmission spectrum are shown in Table 2.

[0113] Liquid composition E1 was applied to the surface of the first light absorber according to Example 3 using a dispenser to form a coating film. The coating film was thoroughly dried at room temperature and then placed in an oven and cured by heat treatment at 45°C for 2 hours, 85°C for 3 hours, 125°C for 1 hour, and 150°C for 1 hour, thereby forming a second light absorber according to Example 3 on the first light absorber. The thickness of the second light absorber according to Example 3 was 188 μm. In this way, an optical filter according to Example 3 was obtained. The transmission spectrum of the optical filter according to Example 3 is shown in FIG. 12, and the characteristic values of this transmission spectrum are shown in Table 1.

[0114] Liquid composition E1 was applied to the surface of a glass substrate having an antifouling coating containing a fluorine component to form a coating film, and this coating film was dried, heated, and cured under the same conditions as for the coating film of liquid composition E1 in the production of the optical filter of Example 3. The cured coating film of liquid composition E1 was peeled off from the glass substrate to obtain a sample for a second light absorber of Example 3. The application conditions for liquid composition E1 were adjusted so that the thickness of the sample for a second light absorber of Example 3 was approximately the same as the thickness of the second light absorber in the optical filter of Example 3. The transmission spectrum of the sample for a second light absorber of Example 3 is shown in FIG. 13, and the characteristic values of this transmission spectrum are shown in Table 3. The transmission spectrum of the sample for a second light absorber of Example 3 can be considered to be the transmission spectrum of the second light absorber of the optical filter of Example 3.

[0115] Example 4 Liquid composition E1 was applied using a dispenser to an area of approximately 76 mm x 76 mm on the surface of a glass substrate having an antifouling coating containing a fluorine component, forming a coating film. The coating film was thoroughly dried at room temperature and then placed in an oven and cured by heat treatment at 45°C for 2 hours, 85°C for 3 hours, 125°C for 1 hour, and 150°C for 1 hour. The cured coating film of liquid composition E1 was peeled from the glass substrate to obtain a second light absorber according to Example 4. The thickness of the second light absorber according to Example 4 was measured using a micrometer and found to be 161 μm. The transmission spectrum of the second light absorber according to Example 4 is shown in FIG. 14, and the characteristic values of the transmission spectrum are shown in Table 3.

[0116] An organic dye having an absorption maximum wavelength in the range of 660 nm to 770 nm, MEK as a solvent, and PVB were mixed, and the mixture was stirred for 2 hours to obtain Liquid Composition H4. The organic dye was soluble in MEK and had little absorption in the visible range. The organic dye contained at least one selected from the group consisting of cyanine dye compounds, squarylium dye compounds, phthalocyanine dye compounds, diimmonium dye compounds, and azo dye compounds. The solid content of the PVB was 99 wt %. The organic dye contained in Liquid Composition H4 was different from the organic dye contained in Liquid Composition H1.

[0117] Liquid composition H4 was applied to the surface of the second light absorber according to Example 4 using a dispenser to form a coating film. This coating film was thoroughly dried at room temperature, and then placed in an oven and subjected to a heat treatment at 130°C for 1 hour to be cured. In this way, a first light absorber according to Example 4 was formed on the second light absorber according to Example 4. The thickness of the first light absorber according to Example 4 was 3 μm. In this way, an optical filter according to Example 4 was obtained. The transmission spectrum of the optical filter according to Example 4 is shown in FIG. 15, and the characteristic values of this transmission spectrum are shown in Table 1.

[0118] Liquid composition H4 was applied to the surface of a glass substrate to form a coating film. This coating film was cured under the same conditions as those for the coating film of liquid composition H4 in the production of the optical filter according to Example 4, to obtain a laminate 4-I corresponding to the first light absorber of the optical filter according to Example 4. The application conditions for liquid composition H4 were adjusted so that the thickness of the cured product of the coating film of liquid composition H4 in laminate 4-I was approximately the same as the thickness of the first light absorber according to Example 4. The transmission spectrum of laminate 4-I is shown in FIG. 16, and the characteristic values of this transmission spectrum are shown in Table 2.

[0119] <Example 5> 5 g of ultraviolet absorber Uvinul 3050 (BASF, 2,2',4,4'-tetrahydroxybenzophenone) and 95 g of ethanol were mixed and stirred for 30 minutes to obtain liquid F1. Next, 2 g of liquid F1 was mixed with 10 g of silicone resin (Shin-Etsu Chemical Co., Ltd., product name: KR-300) and stirred for 30 minutes to obtain liquid composition U1.

[0120] The liquid composition U1 was applied with a dispenser to a main surface of the optical filter according to Example 1 on which the second light absorber was not formed, to form a coating film, and the coating film was thoroughly dried at room temperature. The optical filter according to Example 1 was then placed in an oven, and the coating film was cured by heat treatment under conditions of 45°C for 2 hours and 85°C for 1 hour, thereby forming a third light absorber according to Example 5 on the first light absorber. The thickness of the third light absorber according to Example 5 was 28 μm. In this way, the optical filter according to Example 5 was obtained. The transmission spectrum of the optical filter according to Example 5 is shown in FIG. 17, and the characteristic values of this transmission spectrum are shown in Table 1.

[0121] Liquid composition U1 was applied to the surface of a glass substrate to form a coating film. This coating film was cured under the same conditions as the coating film of liquid composition U1 in the production of the optical filter according to Example 5, to obtain a laminate 5-III corresponding to the third light absorber of the optical filter according to Example 5. The application conditions for liquid composition U1 were adjusted so that the thickness of the cured product of the coating film of liquid composition U1 in laminate 5-III was approximately the same as the thickness of the third light absorber according to Example 5. Transmission spectrum of laminate 5-III is shown in FIG. 18, and the characteristic values of this transmission spectrum are shown in Table 4.

[0122] Example 6 The liquid composition U1 was applied with a dispenser to a main surface of the optical filter according to Example 2 on which the first light absorber was not formed, to form a coating film, and this coating film was thoroughly dried at room temperature. The optical filter according to Example 2 was then placed in an oven, and the coating film was cured by heat treatment under conditions of 45°C for 2 hours and 85°C for 1 hour, thereby forming a third light absorber according to Example 6 on the second light absorber. The thickness of the third light absorber according to Example 6 was 50 μm. In this way, the optical filter according to Example 6 was obtained. The transmission spectrum of the optical filter according to Example 6 is shown in FIG. 19, and the characteristic values of this transmission spectrum are shown in Table 1.

[0123] Liquid composition U1 was applied to the surface of a glass substrate to form a coating film. This coating film was cured under the same conditions as the coating film of liquid composition U1 in the production of the optical filter according to Example 6, to obtain a laminate 6-III corresponding to the third light absorber of the optical filter according to Example 6. The application conditions for liquid composition U1 were adjusted so that the thickness of the cured product of the coating film of liquid composition U1 in laminate 6-III was approximately the same as the thickness of the third light absorber according to Example 6. Transmission spectrum of laminate 6-III This is shown in FIG. 20, and the characteristic values of this transmission spectrum are shown in Table 4.

[0124] Example 7 The liquid composition U1 was applied with a dispenser to a main surface of the optical filter according to Example 3 on which the second light absorber was not formed, to form a coating film, and this coating film was thoroughly dried at room temperature. The optical filter according to Example 3 was then placed in an oven, and the coating film was cured by heat treatment under conditions of 45°C for 2 hours and 85°C for 1 hour, thereby forming a third light absorber according to Example 7 on the first light absorber. The thickness of the third light absorber according to Example 7 was 20 μm. In this way, the optical filter according to Example 7 was obtained. The transmission spectrum of the optical filter according to Example 7 is shown in FIG. 21, and the characteristic values of this transmission spectrum are shown in Table 1.

[0125] The liquid composition U1 was applied to the surface of a glass substrate to form a coating film. This coating film was cured under the same conditions as those for the coating film of the liquid composition U1 in the production of the optical filter according to Example 7. A laminate 7-III corresponding to the third light absorber of the optical filter according to Example 7 was obtained. The conditions for applying the liquid composition U1 were adjusted so that the thickness of the cured coating of the liquid composition U1 in the laminate 7-III would be approximately the same as the thickness of the third light absorber according to Example 7. Transmission spectrum of the laminate 7-III is shown in FIG. 22, and the characteristic values of this transmission spectrum are shown in Table 4.

[0126] Example 8 The liquid composition U1 was applied with a dispenser to a main surface of the optical filter according to Example 4 on which the first light absorber was not formed, to form a coating film, and the coating film was thoroughly dried at room temperature. The optical filter according to Example 4 was then placed in an oven, and the coating film was cured by heat treatment under conditions of 45°C for 2 hours and 85°C for 1 hour, thereby forming a third light absorber according to Example 8 on the second light absorber. The thickness of the third light absorber according to Example 8 was 28 μm. In this manner, the optical filter according to Example 8 was obtained. The transmission spectrum of the optical filter according to Example 8 is shown in FIG. 23, and the characteristic values of this transmission spectrum are shown in Table 1.

[0127] Liquid composition U1 was applied to the surface of a glass substrate to form a coating film. This coating film was cured under the same conditions as the coating film of liquid composition U1 in the production of the optical filter according to Example 8, to obtain a laminate 8-III corresponding to the third light absorber of the optical filter according to Example 8. The application conditions for liquid composition U1 were adjusted so that the thickness of the cured product of the coating film of liquid composition U1 in laminate 8-III was approximately the same as the thickness of the third light absorber according to Example 8. Transmission spectrum of laminate 8-III is shown in FIG. 24, and the characteristic values of this transmission spectrum are shown in Table 4.

[0128] Example 9 Liquid composition E1 was applied using a dispenser to an area of approximately 76 mm x 76 mm on the surface of a glass substrate having an antifouling coating containing a fluorine component, forming a coating film. The coating film was thoroughly dried at room temperature and then placed in an oven and cured by heat treatment at 45°C for 2 hours, 85°C for 3 hours, 125°C for 1 hour, and 150°C for 1 hour. The cured coating film of liquid composition E1 was peeled from the glass substrate to obtain a second light absorber according to Example 9. The thickness of the second light absorber according to Example 9 was measured using a micrometer and found to be 145 μm. The transmission spectrum of the second light absorber according to Example 9 is shown in FIG. 25, and the characteristic values of the transmission spectrum are shown in Table 3.

[0129] Liquid composition H5 was prepared in the same manner as liquid composition H4, except for the following points. The organic dye contained in liquid composition H5 was the same type as the organic dye contained in liquid composition H4, but the concentration of the organic dye in liquid composition H5 was adjusted to be slightly different from the concentration of the organic dye in liquid composition H4. The solid content of the PVB was 99 wt%.

[0130] Liquid composition H5 was applied to the surface of the second light absorber according to Example 9 using a dispenser to form a coating film. This coating film was thoroughly dried at room temperature and then placed in an oven for heat treatment at 130°C for 1 hour to be cured. In this way, a first light absorber according to Example 9 was formed on the second light absorber according to Example 9. The thickness of the first light absorber according to Example 9 was 4 μm. Liquid composition H5 was applied to the surface of a glass substrate to form a coating film. This coating film was cured under the same conditions as the coating film of liquid composition H5 applied to the surface of the second light absorber according to Example 9 to obtain a laminate 9-I corresponding to the first light absorber of the optical filter according to Example 9. The application conditions for liquid composition H5 were adjusted so that the thickness of the cured product of the coating film of liquid composition H5 in laminate 9-I was approximately the same as the thickness of the first light absorber according to Example 9. The transmission spectrum of laminate 9-I is shown in FIG. 26, and the characteristic values of this transmission spectrum are shown in Table 2.

[0131] The liquid composition U1 was applied with a dispenser to the main surface of the second light absorber according to Example 9 on which the first light absorber was not formed, to form a coating film, and the coating film was then thoroughly dried at room temperature. The second light absorber according to Example 9 was placed in an oven, and the coating was cured by heat treatment under conditions of 45°C for 2 hours and 85°C for 1 hour, thereby forming a third light absorber according to Example 9 on the second light absorber. The thickness of the third light absorber according to Example 9 was 50 µm. In this manner, an optical filter according to Example 9 was obtained. The transmission spectrum of the optical filter according to Example 9 is shown in Fig. 27, and the characteristic values of this transmission spectrum and the like are shown in Table 1.

[0132] The liquid composition U1 was applied to the surface of a glass substrate using a dispenser to form a coating film. This coating film was cured under the same conditions as the coating film of the liquid composition U1 in the production of the optical filter according to Example 9, to obtain a laminate 9-III corresponding to the third light absorber of the optical filter according to Example 9. The thickness of the cured coating film of the liquid composition U1 in the layer 9-III is The conditions for applying the liquid composition U1 were adjusted so that the thickness of the laminate 9-III was approximately the same as that of the laminate 9-III. The transmission spectrum is shown in FIG. 28, and the characteristic values of this transmission spectrum are shown in Table 4.

[0133] Example 10 Liquid composition E1 was applied using a dispenser to an area of approximately 76 mm x 76 mm on the surface of a glass substrate having an antifouling coating containing a fluorine component, forming a coating film. The coating film was thoroughly dried at room temperature and then placed in an oven and cured by heat treatment at 45°C for 2 hours, 85°C for 3 hours, 125°C for 1 hour, and 150°C for 1 hour. The cured coating film of liquid composition E1 was peeled from the glass substrate to obtain a second light absorber according to Example 10. The thickness of the second light absorber according to Example 10 was measured using a micrometer and found to be 162 μm. The transmission spectrum of the second light absorber according to Example 10 is shown in FIG. 29, and the characteristic values of the transmission spectrum are shown in Table 3.

[0134] Liquid composition H6 was prepared in the same manner as liquid composition H5, except for the following points. The organic dye contained in liquid composition H6 was the same type as the organic dye contained in liquid composition H5, but the concentration of the organic dye in liquid composition H6 was adjusted to be slightly different from the concentration of the organic dye in liquid composition H5. The solid content of the PVB was 99 wt%.

[0135] Liquid composition H6 was applied to the surface of the second light absorber according to Example 10 using a dispenser to form a coating film. This coating film was thoroughly dried at room temperature and then placed in an oven for heat treatment at 130°C for 1 hour to be cured. In this way, a first light absorber according to Example 10 was formed on the second light absorber according to Example 10. The thickness of the first light absorber according to Example 10 was 2 μm. Liquid composition H6 was applied to the surface of a glass substrate to form a coating film. This coating film was cured under the same conditions as the coating film of liquid composition H6 applied to the surface of the second light absorber according to Example 10 to obtain a laminate 10-I corresponding to the first light absorber of the optical filter according to Example 10. The application conditions for liquid composition H6 were adjusted so that the thickness of the cured product of the coating film of liquid composition H6 in laminate 10-I was approximately the same as the thickness of the first light absorber according to Example 10. The transmission spectrum of laminate 10-I is shown in FIG. 30, and the characteristic values of this transmission spectrum are shown in Table 2.

[0136] Liquid composition U1 was applied with a dispenser to a main surface of the second light absorber according to Example 10 on which the first light absorber was not formed, to form a coating film, and this coating film was thoroughly dried at room temperature. Thereafter, the second light absorber according to Example 10 was placed in an oven, and the coating film was cured by heat treatment under conditions of 45°C for 2 hours and 85°C for 1 hour, thereby forming a third light absorber according to Example 10 on the second light absorber. The thickness of the third light absorber according to Example 10 was 20 μm. In this manner, an optical filter according to Example 10 was obtained. The transmission spectrum of the optical filter according to Example 10 is shown in FIG. 31, and the characteristic values of this transmission spectrum are shown in Table 1.

[0137] The liquid composition U1 was applied to the surface of a glass substrate using a dispenser to form a coating film. This coating film was cured under the same conditions as those for the coating film of the liquid composition U1 in the production of the optical filter according to Example 10. to obtain a laminate 10-III corresponding to the third light absorber of the optical filter according to Example 10. The thickness of the cured coating film of the liquid composition U1 in the laminate 10-III was the same as that of Example 10. The conditions for applying the liquid composition U1 were adjusted so that the thickness was approximately the same as that of the third light absorber. The transmission spectrum of the laminate 10-III is shown in FIG. 32, and the characteristic values of this transmission spectrum are shown in Table 4. show.

[0138] Example 11 Liquid composition E1 was applied using a dispenser to an area of approximately 76 mm x 76 mm on the surface of a glass substrate having an antifouling coating containing a fluorine component, forming a coating film. The coating film was thoroughly dried at room temperature and then placed in an oven and cured by heat treatment at 45°C for 2 hours, 85°C for 3 hours, 125°C for 1 hour, and 150°C for 1 hour. The cured coating film of liquid composition E1 was peeled from the glass substrate to obtain a second light absorber according to Example 11. The thickness of the second light absorber according to Example 11 was measured using a micrometer and found to be 160 μm. The transmission spectrum of the second light absorber according to Example 11 is shown in FIG. 33, and the characteristic values of the transmission spectrum are shown in Table 3.

[0139] Liquid composition H7 was prepared in the same manner as liquid composition H5, except for the following points. The organic dye contained in liquid composition H7 was the same type as the organic dye contained in liquid composition H5, but the concentration of the organic dye in liquid composition H7 was adjusted to be slightly different from the concentration of the organic dye in liquid composition H5. The solid content of the PVB was 99 wt%.

[0140] Liquid composition H7 was applied to the surface of the second light absorber according to Example 11 using a dispenser to form a coating film. This coating film was thoroughly dried at room temperature and then placed in an oven for heat treatment at 130°C for 1 hour to be cured. In this way, a first light absorber according to Example 11 was formed on the second light absorber according to Example 11. The thickness of the first light absorber according to Example 11 was 3 μm. Liquid composition H7 was applied to the surface of a glass substrate to form a coating film. This coating film was cured under the same conditions as the coating film of liquid composition H7 applied to the surface of the second light absorber according to Example 11 to obtain a laminate 11-I corresponding to the first light absorber of the optical filter according to Example 11. The application conditions for liquid composition H7 were adjusted so that the thickness of the cured product of the coating film of liquid composition H7 in laminate 11-I was approximately the same as the thickness of the first light absorber according to Example 11. The transmission spectrum of laminate 11-I is shown in FIG. 34, and the characteristic values of this transmission spectrum are shown in Table 2.

[0141] 5 g of the ultraviolet absorber Tinuvin (BASF, 2-(2-hydroxy-5-methylphenyl)benzotriazole) and 95 g of toluene were mixed and stirred for 30 minutes to obtain F2 liquid. Next, 2 g of F2 liquid and 10 g of silicone resin (Shin-Etsu Chemical Co., Ltd., product name: KR-300) were mixed and stirred for 30 minutes to obtain liquid composition U2 liquid.

[0142] Liquid composition U2 was applied with a dispenser to a main surface of the second light absorber according to Example 11 on which the first light absorber was not formed, to form a coating film, and this coating film was thoroughly dried at room temperature. Thereafter, the second light absorber according to Example 11 was placed in an oven, and the coating film was cured by heat treatment under conditions of 45°C for 2 hours and 85°C for 1 hour, thereby forming a third light absorber according to Example 11 on the second light absorber. The thickness of the third light absorber according to Example 11 was 28 μm. In this manner, an optical filter according to Example 11 was obtained. The transmission spectrum of the optical filter according to Example 11 is shown in FIG. 35, and the characteristic values of this transmission spectrum are shown in Table 1.

[0143] The liquid composition U2 was applied to the surface of the glass substrate using a dispenser to form a coating film. This coating film was cured under the same conditions as the coating film of the liquid composition U2 in the production of the optical filter according to Example 11, to obtain a laminate 11-III corresponding to the third light absorber of the optical filter according to Example 11. The thickness of the cured coating film of the liquid composition U2 in the laminate 11-III was the same as that of Example 11. The coating conditions of the liquid composition U2 were adjusted so that the thickness was approximately the same as that of the third light absorber. The transmission spectrum of the laminate 11-III is shown in FIG. 36, and the characteristic values of this transmission spectrum are shown in Table 4. show.

[0144] Example 12 Liquid composition E1 was applied using a dispenser to an area of approximately 76 mm x 76 mm on the surface of a glass substrate having an antifouling coating containing a fluorine component, forming a coating film. The coating film was thoroughly dried at room temperature and then placed in an oven and cured by heat treatment at 45°C for 2 hours, 85°C for 3 hours, 125°C for 1 hour, and 150°C for 1 hour. The cured coating film of liquid composition E1 was peeled from the glass substrate to obtain a second light absorber according to Example 12. The thickness of the second light absorber according to Example 12 was measured using a micrometer and found to be 162 μm. The transmission spectrum of the second light absorber according to Example 12 is shown in FIG. 37, and the characteristic values of the transmission spectrum are shown in Table 3.

[0145] Liquid composition H8 was prepared in the same manner as liquid composition H5, except for the following points. The organic dye contained in liquid composition H8 was the same type as the organic dye contained in liquid composition H5, but the concentration of the organic dye in liquid composition H8 was adjusted to be slightly different from the concentration of the organic dye in liquid composition H5. The solid content of the PVB was 99 wt%.

[0146] Liquid composition H8 was applied to the surface of the second light absorber according to Example 12 using a dispenser to form a coating film. This coating film was thoroughly dried at room temperature and then placed in an oven for heat treatment at 130°C for 1 hour to be cured. In this way, a first light absorber according to Example 12 was formed on the second light absorber according to Example 12. The thickness of the first light absorber according to Example 12 was 2 μm. Liquid composition H8 was applied to the surface of a glass substrate to form a coating film. This coating film was cured under the same conditions as the coating film of liquid composition H8 applied to the surface of the second light absorber according to Example 12 to obtain a laminate 12-I corresponding to the first light absorber of the optical filter according to Example 12. The application conditions for liquid composition H8 were adjusted so that the thickness of the cured product of the coating film of liquid composition H8 in laminate 12-I was approximately the same as the thickness of the first light absorber according to Example 12. The transmission spectrum of laminate 12-I is shown in FIG. 38, and the characteristic values of this transmission spectrum are shown in Table 2.

[0147] Liquid composition U2 was applied with a dispenser to a main surface of the second light absorber according to Example 12 on which the first light absorber was not formed, to form a coating film, and this coating film was thoroughly dried at room temperature. Thereafter, the second light absorber according to Example 12 was placed in an oven, and the coating film was cured by heat treatment under conditions of 45°C for 2 hours and 85°C for 1 hour, thereby forming a third light absorber according to Example 12 on the second light absorber. The thickness of the third light absorber according to Example 12 was 20 μm. In this manner, an optical filter according to Example 12 was obtained. The transmission spectrum of the optical filter according to Example 12 is shown in FIG. 39, and the characteristic values of this transmission spectrum are shown in Table 1.

[0148] The liquid composition U2 was applied to the surface of the glass substrate using a dispenser to form a coating film. This coating film was cured under the same conditions as the coating film of the liquid composition U2 in the production of the optical filter according to Example 12, to obtain a laminate 12-III corresponding to the third light absorber of the optical filter according to Example 12. The thickness of the cured coating film of the liquid composition U2 in the laminate 12-III was the same as that of Example 12. The coating conditions of the liquid composition U2 were adjusted so that the thickness was approximately the same as that of the third light absorber. The transmission spectrum of the laminate 12-III is shown in FIG. 40, and the characteristic values of this transmission spectrum are shown in Table 4. show.

[0149] Laminates 2-I, 4-I, 5-III, 6-III, 7-III, 8-III, 9-I, 9-III, 1 The gases used to prepare 0-I, 10-III, 11-I, 11-III, 12-I, and 12-III The transmission spectrum of the glass substrate is shown in FIG.

[0150] As shown in Table 1, the optical filters according to Examples 1 to 12 satisfied the above conditions (I), (II), (III), and (IV). The absolute value Δλ S / F The wavelength was 190 nm or more and 280 nm or less. In optical filters, T 350 The optical fibers according to Examples 1 to 12 were 20% or less. In Ruta, T M 750-1000 The optical filters according to Examples 1 to 12 Hey, T M 800-950 In the optical filters according to Examples 1 to 12, ΔT 1% was greater than 400 nm.

[0151] Table 2 and Fig. 41 suggest that in the optical filters according to Examples 1 to 12, the first optical absorber satisfies the above conditions (i1), (i2), (i3), (i4), and (i5). In addition, it is suggested that the first optical absorber satisfies the conditions (i6), (i7), and (i8). In the first optical absorber, -1.2 [% / nm] ≦ ΔT (2) / Δλ (2) L The condition of ≦-0.6[% / nm] is met It was suggested that this would be achieved.

[0152] According to Table 3, in the optical filters according to Examples 1 to 12, the second light absorber satisfied the above conditions (ii1), (ii2), (ii3), (ii4), and (ii5). In addition, the second light absorber The second absorber satisfies the conditions (ii6), (ii7), and (ii8). (3)M 750-1100 The value was 0.5% or more and 6% or less. In the second light absorber, -0.9[% / nm] ≦ΔT (3) / Δλ (3) H The condition of ≦-0.78[% / nm] is met, and -0.9[% / nm]≦ΔT (3) / Δλ (3) 750 The condition of 0.75[% / nm]≦ΔT was met for the second optical absorber. (3) / Δλ (3) L The condition of ≦1.6[% / nm] is met. In the second optical absorber, Δλ (3) 50% was between 270 nm and 350 nm.

[0153] 41 suggests that the third optical absorber satisfies the above conditions (iii1), (iii2), and (iii3) in the optical filters according to Examples 5 to 12. In addition, the third optical absorber satisfies the condition 3.0 [% / nm]≦ΔT (4) / Δλ (4) L ≦4.2[% / nm It was suggested that the following conditions were met:

[0154] [Table 1]

[0155] [Table 2]

[0156] [Table 3]

[0157] [Table 4] [Explanation of symbols]

[0158] 1a, 1b, 1c, 1d Optical filters 11 First light absorber 12 Second light absorber 13 Third light absorber

Claims

1. An optical filter, a first light absorber comprising an organic dye; a second light absorber containing a copper component and absorbing at least a portion of infrared light; When light having a wavelength in the range of 300 nm to 1200 nm is incident on the optical filter, the optical filter exhibits a first transmission spectrum that satisfies the following conditions (I), (II), (III), and (IV): Optical filters. (I) The average transmittance in the wavelength range of 450 nm to 600 nm is 76% or more, and (II) The first cutoff wavelength, which is a wavelength showing a transmittance of 50% in the wavelength range of 350 nm to 470 nm, is in the range of 360 nm to 450 nm. (III) A wavelength that exhibits a transmittance of 50% in the wavelength range of 580 nm to 720 nm. Two cutoff wavelengths exist in the range of 600 nm to 700 nm. (IV) The maximum transmittance in the wavelength range of 700 nm to 750 nm is 5% or less.

2. 2. The optical filter according to claim 1, wherein an absolute value of a difference between the second cutoff wavelength and the first cutoff wavelength is 190 nm or more and 280 nm or less.

3. 3. The optical filter according to claim 1, wherein the transmittance of the first transmission spectrum at a wavelength of 350 nm is 20% or less.

4. 4. The optical filter according to claim 1, wherein the maximum value of the transmittance in the wavelength range of 750 nm to 1000 nm of the first transmission spectrum is 2% or less.

5. 5. The optical filter according to claim 4, wherein the maximum value of the transmittance in the wavelength range of 800 nm to 950 nm of the first transmission spectrum is 1% or less.

6. 6. The optical filter according to claim 1, wherein the absolute value of the difference between the maximum wavelength and the minimum wavelength exhibiting a transmittance of 1% in a wavelength range of 700 nm to 1200 nm of the first transmission spectrum is 400 nm or more.

7. 7. The optical filter according to claim 1, wherein a second transmission spectrum, which is a transmission spectrum of the first light absorber when light having a wavelength in a range of 300 nm to 1200 nm is incident on the first light absorber, satisfies the following conditions (i1), (i2), (i3), (i4), and (i5): (i1) The wavelength at which the transmittance shows a minimum value is 650 nm or more and 770 nm or less in the wavelength range of 550 nm to 850 nm. (i2) The minimum wavelength showing a transmittance of 70% in the wavelength range of 550 nm to 850 nm is 570 nm or more and 670 nm or less. (i3) The minimum wavelength showing 50% transmittance in the wavelength range of 550 nm to 850 nm is 590 nm or more and 700 nm or less. (i4) The minimum wavelength showing a transmittance of 20% in the wavelength range of 550 nm to 850 nm is 630 nm or more and 720 nm or less. (i5) The average transmittance in the wavelength range of 450 nm to 600 nm is 76% or more.

8. 8. The optical filter according to claim 7, wherein the second transmission spectrum satisfies at least one of the following conditions (i6), (i7), and (i8): (i6) The absolute value of the difference between the maximum and minimum wavelengths showing a transmittance of 70% in the wavelength range of 550 nm to 850 nm is 120 nm or more and 250 nm or less. (i7) The maximum wavelength showing 50% transmittance in the wavelength range of 550 nm to 850 nm. The absolute value of the difference from the minimum value is 70 nm or more and 210 nm or less. (i8) The absolute value of the difference between the maximum and minimum wavelengths showing a transmittance of 20% in the wavelength range of 550 nm to 850 nm is 30 nm or more and 160 nm or less.

9. The minimum wavelength λ at which the second transmission spectrum exhibits a transmittance of 20% in the wavelength range of 550 nm to 850 nm (2) 20%L and the wavelength of the second transmission spectrum is 550 nm to 850 nm. The minimum wavelength λ at which 70% transmittance is achieved in the range of (2) 70%L is -1.2 [% / nm ]≦(20-70) / (λ (2) 20%L -λ (2) 70%L 9. The optical filter according to claim 7, wherein the condition of 0.6 [% / nm] is satisfied.

10. The optical filter according to any one of claims 1 to 9, wherein the organic dye comprises at least one selected from the group consisting of a cyanine dye, a squarylium dye, a phthalocyanine dye, a diimmonium dye, and an azo dye.

11. A third transmission spectrum, which is a transmission spectrum of the second light absorber when light having a wavelength in a range of 300 nm to 1200 nm is incident on the second light absorber, satisfies the following conditions (ii1), (ii2), (ii3), (ii4), and (ii5): Optical filters. (ii1) Wavelength λ showing 70% transmittance in the wavelength range of 550 nm to 750 nm (3) 70%H is 620 nm or more and 690 nm or less. (ii2) Wavelength λ showing 50% transmittance in the wavelength range of 550 nm to 750 nm (3) 50%H is 640 nm or more and 720 nm or less. (ii3) Wavelength λ showing 20% transmittance in the wavelength range of 550 nm to 750 nm (3) 20%H is 670 nm or more and 750 nm or less. (ii4) Transmittance T at a wavelength of 750 nm (3) 750 is 0.5% or more and 6% or less. (ii5) The average transmittance in the wavelength range of 450 nm to 600 nm is 76% or more. 。

12. 12. The optical filter according to claim 11, wherein the maximum value of the transmittance in the wavelength range of 750 nm to 1100 nm of the third transmission spectrum is 0.5% or more and 6% or less.

13. The wavelength λ (3) 20%H , the wavelength λ (3) 70%H , and the transmittance T (3) 750 satisfy the conditions of -0.9 [% / nm] ≤ (20 - 70) / (λ (3) 20%H - λ (3) 70%H ) ≤ -0.78 [% / nm] and -0.9 [% / nm] ≤ (T (3) 750 - 70) / (750 - λ (3) 70%H ) ≤ -0.5 [% 13. The optical filter according to claim 11, wherein at least one of the following conditions is satisfied:

14. The third transmission spectrum satisfies at least the following conditions (ii6), (ii7), and (ii8): The optical filter according to any one of claims 11 to 13, which satisfies one of the above requirements. (ii6) Wavelength λ showing 70% transmittance in the wavelength range of 300 nm to 450 nm (3) 70%L is 360 nm or more and 430 nm or less. (ii7) Wavelength λ showing 50% transmittance in the wavelength range of 300 nm to 450 nm (3) 50%L is 340 nm or more and 390 nm or less. (ii8) Wavelength λ showing 20% transmittance in the wavelength range of 300 nm to 450 nm (3) 20%L is 330 nm or more and 380 nm or less.

15. The wavelength λ (3) 70%L and the wavelength λ (3) 20%L is 0.75 [% / nm] ≦ (70−20) / (λ (3) 70%L -λ (3) 20%L 15. The optical filter according to claim 14, wherein the condition of 1.6 [% / nm] is satisfied.

16. The wavelength λ (3) 50%H and the third transmission spectrum has a wavelength range of 300 nm to 450 nm. Wavelength λ at which 50% transmittance is exhibited (3) 50%L The absolute value of the difference is 270 nm or more and 350 The optical filter according to any one of claims 11 to 15, wherein the thickness is 1 nm or less.

17. The optical filter according to any one of claims 1 to 16, wherein the second light absorber contains a light absorbing compound including the copper component and at least one selected from the group consisting of phosphonic acid, sulfonic acid, and carboxylic acid.

18. Further comprising a third light absorber containing an ultraviolet absorber; 18. The optical filter according to any one of claims 1 to 17, wherein a fourth transmission spectrum, which is a transmission spectrum of the third optical absorber when light having a wavelength in a range of 300 nm to 1200 nm is incident on the third optical absorber, satisfies the following conditions (iii1), (iii2), and (iii3): (iii1) Wavelength λ showing 70% transmittance in the wavelength range of 300 nm to 450 nm (4) 70%L is 350 nm or more and 450 nm or less. (iii2) Wavelength λ showing 50% transmittance in the wavelength range of 300 nm to 450 nm (4) 50%L is 340 nm or more and 440 nm or less. (iii3) Wavelength λ showing 20% transmittance in the wavelength range of 300 nm to 450 nm (4) 20%L is 340 nm or more and 440 nm or less.

19. The wavelength λ (4) 70%L and the wavelength λ (4) 20%L is 3.0 [% / nm]≦(70−20) / (λ (4) 70%L -λ (4) 20%L 19. The optical filter according to claim 18, wherein the condition of 4.2 [% / nm] is satisfied.

20. 20. The optical filter according to claim 18, wherein the ultraviolet absorber comprises at least one selected from the group consisting of a benzophenone-based compound, a benzotriazole-based compound, a triazine-based compound, an acrylonitrile-based compound, and a salicylic acid-based compound.

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