JP2021189251A - Light absorber, light absorber article, imaging device and light absorptive composition - Google Patents

Abstract

To provide a light absorber in which a transmission coefficient in a red band easily increases and which can excellently shield the near-infrared ray.SOLUTION: A transmission spectrum of a light absorber 10 at an incidence angle of 0° satisfies the following conditions. (I) An average value of a transmission coefficient within a range of a wavelength between 450 nm and 600 nm is equal to or greater than 75%. (II) The first wavelength in which the transmission coefficient becomes 50% within a range of the wavelength between 350 nm and 450 nm is equal to or greater than 380 nm and equal to or less than 440 nm. (III) The second wavelength in which the transmission coefficient becomes 50% within a range of the wavelength between 650 nm and 750 nm is equal to or greater than 680 nm and equal to or less than 740 nm. (IV) The maximum value of the transmission coefficient within a range of the wavelength between 350 nm and 370 nm is equal to or less than 1%. (V) The maximum value of the transmission coefficient within a range of the wavelength between 800 nm and 900 nm is equal to or less than 5%. (VI) The maximum value of the transmission coefficient within a range of the wavelength between 1100 nm and 1200 nm is equal to or less than 5%.SELECTED DRAWING: Figure 1A

Description

The present invention relates to a light absorber, an article with a light absorber, an image pickup device, and a light absorbent composition.

In an image pickup device using a solid-state image sensor such as a CCD (Charge Coupled Device) or CMOS (Complementary Metal Oxide Semiconductor), various optical filters are placed in front of the solid-state image sensor in order to obtain an image with good color reproducibility. Has been done. In general, a solid-state image sensor has spectral sensitivity in a wide wavelength range from the ultraviolet region to the infrared region. On the other hand, human luminosity factor exists only in the visible light region. Therefore, in order to bring the spectral sensitivity of the solid-state image sensor in the image pickup device closer to that of humans, there is known a technique of arranging an optical filter that shields a part of infrared rays or ultraviolet rays in front of the solid-state image sensor. ..

Conventionally, as such an optical filter, a filter that shields infrared rays or ultraviolet rays by utilizing light reflection by a dielectric multilayer film has been generally used. On the other hand, in recent years, an optical filter provided with a film containing a light absorber has attracted attention. Since the transmittance characteristics of an optical filter equipped with a film containing a light absorber are not easily affected by the angle of incidence, a good image with little change in color even when light is obliquely incident on the optical filter in an image pickup device can be obtained. Obtainable. In addition, the light absorption type optical filter that does not use a light reflection film can suppress the generation of ghosts and flares caused by multiple reflections by the light reflection film, so that a good image can be obtained in backlight conditions and night scene photography. Cheap. In addition, the optical filter provided with the film containing the light absorber is advantageous in terms of miniaturization and thinning of the image pickup apparatus.

As such a light absorber, a light absorber formed by phosphonic acid and copper ions is known. For example, Patent Document 1 describes an optical filter including a light absorbing layer containing a light absorbing agent formed of a phosphonic acid (phenyl-based phosphonic acid) having a phenyl group or a halogenated phenyl group and copper ions. Has been done.

Further, Patent Document 2 describes an optical filter provided with a UV-IR absorption layer capable of absorbing infrared rays and ultraviolet rays. The UV-IR absorbent layer contains a UV-IR absorbent formed by phosphonic acid and copper ions. The UV-IR absorbent composition contains, for example, a phenyl-based phosphonic acid and a phosphonic acid having an alkyl group or an alkyl halide group (alkyl-based phosphonic acid) so that the optical filter satisfies a predetermined optical property. ing.

Further, Patent Document 3 describes an infrared cut filter including an organic dye-containing layer and a copper phosphonate-containing layer.

On the other hand, Patent Document 4 describes an optical filter including an absorption layer, a reflection layer, and a transparent substrate, which satisfies a predetermined requirement in a spectral transmittance curve having an incident angle of 0 °. The absorbent layer contains a near-infrared absorbing dye such as a squarylium dye.

Japanese Patent No. 6339755 Japanese Patent No. 6232161 Japanese Patent No. 6281023 International Publication No. 2020/004641

In the optical filters described in Patent Documents 1 to 3, the cutoff wavelength near the infrared region is adjusted to the range of 600 to 680 nm. Although this is advantageous from the viewpoint of satisfactorily shielding infrared rays, it cannot be said that it is advantageous from the viewpoint of increasing the transmittance in the red band. On the other hand, in the optical filter described in Patent Document 4, although the wavelength at which the transmittance is 50% near the infrared region is 680 nm or more, a reflective layer is required, and the absorbing layer is not sufficient to shield light. Must be supplemented by. Therefore, in the optical filter described in Patent Document 4, a complicated process is required for forming the reflective layer.

Therefore, the present invention provides a light absorber that tends to have high transmittance in the visible light region, particularly in the red band, and can satisfactorily shield near infrared rays.

The present invention
Provided is a light absorber whose transmission spectrum at an incident angle of 0 ° satisfies the following conditions (I), (II), (III), (IV), (V), and (VI).
(I) The average value of the transmittance in the wavelength range of 450 nm to 600 nm is 75% or more.
(II) The first wavelength having a transmittance of 50% in the wavelength range of 350 nm to 450 nm is 380 nm or more and 440 nm or less.
(III) The second wavelength having a transmittance of 50% in the wavelength range of 650 nm to 750 nm is 680 nm or more and 740 nm or less.
(IV) The maximum value of the transmittance in the wavelength range of 350 nm to 370 nm is 1% or less.
(V) The maximum value of the transmittance in the wavelength range of 800 nm to 900 nm is 5% or less.
(VI) The maximum value of the transmittance in the wavelength range of 1100 nm to 1200 nm is 5% or less.

Further, the present invention
Goods and
The light absorber and the above-mentioned light absorber formed on a part of the surface of the article.
Provide an article with a light absorber.

Further, the present invention
A light-absorbing composition
The transmission spectra of the light absorber obtained by curing the light-absorbing composition at an incident angle of 0 ° are as follows (i), (ii), (iii), (iv), (v), and (vi). To provide a light-absorbing composition satisfying the above conditions.
(I) The average value of the transmittance in the wavelength range of 450 nm to 600 nm is 75% or more.
(Ii) The first wavelength having a transmittance of 50% in the wavelength range of 350 nm to 450 nm is 380 nm or more and 440 nm or less.
(Iii) The second wavelength having a transmittance of 50% in the wavelength range of 650 nm to 750 nm is 680 nm or more and 740 nm or less.
(Iv) The maximum value of the transmittance in the wavelength range of 350 nm to 370 nm is 1% or less.
(V) The maximum value of the transmittance in the wavelength range of 800 nm to 900 nm is 5% or less.
(Vi) The maximum value of the transmittance in the wavelength range of 1100 nm to 1200 nm is 5% or less.

In the above light absorber, the transmittance tends to be high in the visible light region, particularly in the red band. In addition, the above light absorber can satisfactorily shield near infrared rays.

FIG. 1A is a cross-sectional view showing an example of a light absorber according to the present invention. FIG. 1B is a cross-sectional view showing an example of an article with a light absorber according to the present invention. FIG. 1C is a cross-sectional view showing another example of the article with a light absorber according to the present invention. FIG. 1D is a cross-sectional view showing an example of an optical member provided with a light absorber according to the present invention. FIG. 2 is a diagram showing an example of an image pickup apparatus according to the present invention. FIG. 3A is a transmission spectrum of the optical filter according to the first embodiment. FIG. 3B is a transmission spectrum of the optical filter according to the first embodiment. FIG. 3C is a transmission spectrum of the optical filter according to the first embodiment. FIG. 4A is a transmission spectrum of the optical filter according to the second embodiment. FIG. 4B is a transmission spectrum of the optical filter according to the second embodiment. FIG. 4C is a transmission spectrum of the optical filter according to the second embodiment. FIG. 5A is a transmission spectrum of the optical filter according to the third embodiment. FIG. 5B is a transmission spectrum of the optical filter according to the third embodiment. FIG. 5C is a transmission spectrum of the optical filter according to the third embodiment. FIG. 6 is a transmission spectrum of the optical filter according to Comparative Example 1. FIG. 7 is a transmission spectrum of the optical filter according to Comparative Example 2. FIG. 8 is a transmission spectrum of the optical filter according to Comparative Example 3. FIG. 9 is a transmission spectrum of the optical filter according to Comparative Example 4.

It is conceivable to mount a camera equipped with a CMOS sensor or the like on the vehicle as a part of the in-vehicle system. In addition, it is conceivable to use such cameras for driving devices such as drones and autonomous robots, mobile devices, and transport devices. In this case, the camera mainly acquires the external situation as information such as a captured image, and the acquired information can support the operation of the driver, the operator, or the control system for autopilot. In this case, from the viewpoint of improving the recognition accuracy of the external environment, it is advantageous that the camera is provided with an optical filter having high transmittance in the visible light region and capable of satisfactorily blocking infrared rays. The visible light region is an electromagnetic wave in a wavelength range that can be recognized as light by humans, the lower limit of the wavelength range is 360 to 400 nm, and the upper limit of the wavelength range is 760 to 830 nm. Further, according to Japanese Industrial Standards (JIS) Z 8120: 2001, the visible light region may be in the range of 380 to 780 nm. Infrared rays, especially near infrared rays (NIR), are defined as electromagnetic waves having a wavelength in the range of up to about 1400 nm, which is beyond the wavelength range of the visible light region.

At traffic lights, road signs, etc., signs related to danger or safety may be shown in red. For example, in addition to red lights, regulatory signs such as vehicle entry prohibition, stop, and driving in traffic signs (road signs) fall under such indications. In the transmission spectrum of the optical filter, the high transmittance in the wavelength range corresponding to red is important for accurately recognizing surrounding objects including the above-mentioned red signal, regulatory sign, and the like. The red color displayed on the regulation sign or the like shows high reflectance in a wavelength range in which the lower limit is 580 to 620 nm and the upper limit exceeds about 780 nm, although it depends on the specifications of the member such as the retroreflective sheet. Assuming that the upper limit of the wavelength in the visible light region is 780 nm, the transmittance in the wavelength range of 580 to 780 nm is high, or the transmittance is high in the wavelength range of 620 to 760 nm, or the wavelength is 620 to 750 nm in the transmission spectrum of the optical filter. It is advantageous that the transmittance in the range of is high.

In addition, the fact that the optical filter can shield infrared rays well means that, for example, the camera cannot obtain a good captured image due to the influence of sensing using infrared rays in a vehicle, a mobile device, or a transport device traveling in the vicinity. It is important to control the problem. It is understood that the characteristics of the optical filter described in Patent Document 4 are adjusted from such a viewpoint. On the other hand, the optical filter described in Patent Document 4 includes a reflective layer in addition to the absorbing layer. Therefore, the present inventor has repeated a great deal of trial and error in order to develop a technique capable of increasing the transmittance in the red band and satisfactorily shielding near infrared rays without using a reflective layer. As a result, the present invention was finally completed.

In the present specification, unless otherwise specified, the visible light region or the visible light region is defined as a band having a wavelength of 380 to 780 nm, and the red band is defined as a band having a wavelength of 580 to 780 nm or one within the range. It is defined as the band of the part. Unless otherwise specified, infrared rays are defined as light (electromagnetic waves) having a wavelength larger than the upper limit of the visible light range of 780 nm and belonging to a wavelength range of up to 1400 nm, and correspond to near infrared rays (NIR). .. Ultraviolet rays are defined as light (electromagnetic waves) belonging to the range from a wavelength of 280 nm to 380 nm, which is the lower limit of the visible light region, and correspond to a part of UV-A and UV-B.

Hereinafter, embodiments of the present invention will be described. The following description relates to an example of the present invention, and the present invention is not limited to the following embodiments.

FIG. 1A is a cross-sectional view showing the light absorber 10. The transmission spectrum of the light absorber 10 at an incident angle of 0 ° satisfies the following conditions (I), (II), (III), (IV), (V), and (VI).
(I) the mean value T ^A ₀ transmittance in the wavelength range of 450 nm to 600 nm _(450-600) is 75% or more.
^{(II) The first wavelength λ 500} _{(UV) at} which the transmittance is 50% in the wavelength range of 350 nm to 450 nm is 380 nm or more and 440 nm or less.
^{(III) The second wavelength λ 500} _{(IR) at} which the transmittance is 50% in the wavelength range of 650 nm to 750 nm is 680 nm or more and 740 nm or less.
(IV) The maximum value T ^M ₀ transmittance in the wavelength range of 350nm~370nm _(350-370) is 1% or less.
(V) maximum T ^M ₀ transmittance in the wavelength range of 800 nm to 900 nm _(800-900) is not more than 5%.
(VI) The maximum value T ^M ₀ transmittance in the wavelength range of 1100nm~1200nm _(1100-1200) is 5% or less.

When the conditions (I), (II), and (III) are satisfied, the transmittance in the visible light region tends to be high, and in particular, when the condition (III) is satisfied, light absorption is likely to occur. The transmittance in the red band of the body 10 tends to be high. In addition, when the conditions (V) and (VI) are satisfied, the light absorber 10 can satisfactorily shield infrared rays. Further, when the condition (IV) is satisfied, the light absorber 10 can satisfactorily shield the ultraviolet rays.

Respect conditions (I), the average value T ^A _{0 (450-600)} is desirably 80% or more, more preferably 85% or more. In addition, the transmission spectrum of the light absorber 10 at an incident angle of 0 ° preferably further satisfies the following condition (Ia).
(Ia) mean T ^A ₀ transmittance in the wavelength range of 650nm~670nm _(650-670) of at least 70%.

Respect conditions (Ia), the average value T ^A _{0 (650-670)} is desirably at 72% or more, more desirably 74% or more.

Regarding the condition (II), the first wavelength λ ⁵⁰⁰ _(UV) is preferably 385 nm or more and 420 nm or less, and more preferably 390 nm or more and 410 nm or less.

Regarding the condition (III), the second wavelength λ ⁵⁰⁰ _(IR) is preferably more than 680 nm and 740 nm or less, more preferably 685 nm or more and 730 nm or less, and further preferably 690 nm or more and 720 nm or less.

Relates condition (IV), the maximum value T ^M _{0 (350-370)} is preferably 0.5% or less.

Relates condition (V), the maximum value T ^M _{0 (800-900)} is preferably 3% or less.

Respect conditions (VI), the maximum value T ^M _{0 (1100-1200)} is preferably 3% or less.

The transmission spectrum of the light absorber 10 at an incident angle of 0 ° further satisfies, for example, the following condition (VII). As a result, the transmittance of the light absorber 10 in the red band tends to be higher with certainty.
_{(VII) The transmittance T 0 (750} ) at a wavelength of 750 nm is 7% or more.

With respect to the condition (VII), the transmittance T _{0 (750)} is preferably 10% or more, and more preferably 15% or more.

The transmission spectrum of the light absorber 10 at an incident angle of 0 ° further satisfies, for example, the following condition (VIII). As a result, the transmittance of the light absorber 10 in the red band tends to be higher with certainty.
_{(VIII) The transmittance T 0 (780} ) at a wavelength of 780 nm is 3% or more.

With respect to the condition (VIII), the transmittance T _{0 (780)} is preferably 4% or more, and more preferably 5% or more.

The transmission spectrum of the light absorber 10 at an incident angle of 55 ° has, for example, a third wavelength λ ⁵⁰ _{55 (UV)} having a transmittance of 50% in the wavelength range of 350 nm to 450 nm. Absolute value Δλ ⁵⁰ _0/55 of the difference between the third wavelength λ ⁵⁰ _{55 (UV)} and the first wavelength _{^{λ 50 0 (UV) (UV}} ) is, for example, 12nm or less. As a result, the incident angle dependence of the transmission spectrum of the light absorber 10 tends to be small. Therefore, for example, it is possible to suppress the change in color in the central portion and the peripheral portion of the image obtained by the image pickup apparatus provided with the light absorber 10. In addition, the image pickup apparatus provided with the light absorber 10 can suppress the change in color in the image of the subject existing in the range of the angle of view that can be captured. The absolute value Δλ ⁵⁰ _{0/55 (UV)} is preferably 10 nm or less, more preferably 8 nm or less, and even more preferably 6 nm or less.

The transmission spectrum of the light absorber 10 at an incident angle of 55 ° has, for example, a fourth wavelength λ ⁵⁰ _{55 (IR)} having a transmittance of 50% in the wavelength range of 650 nm to 750 nm. Absolute value Δλ ⁵⁰ _0/55 of the difference between the fourth wavelength λ ⁵⁰ _{55 (IR)} and the second wavelength _{^{λ 50 0 (IR) (IR}} ) , for example, or less 24 nm. As a result, the incident angle dependence of the transmission spectrum of the light absorber 10 tends to be small. Therefore, for example, it is possible to suppress the change in color in the central portion and the peripheral portion of the image obtained by the image pickup apparatus provided with the light absorber 10. In addition, the image pickup apparatus provided with the light absorber 10 can suppress the change in color in the image of the subject existing in the range of the angle of view that can be captured. Absolute value Δλ ⁵⁰ _{0/55 (IR)} is desirably at 20nm or less, more preferably not more than 18 nm, more desirably less than 16 nm.

The transmission spectrum of the light absorber 10 at an incident angle of 45 ° has, for example, a wavelength λ ⁵⁰ _{45 (UV)} having a transmittance of 50% in the wavelength range of 350 nm to 450 nm. Wavelength lambda ⁵⁰ ₄₅ absolute value [Delta] [lambda] ⁵⁰ of the difference between _(UV) and the first wavelength lambda ⁵⁰ _{0 (UV) 0/45 (UV)} is, for example, 10nm or less, desirably at 8nm or less, and more preferably 5nm It is as follows.

The transmission spectrum of the light absorber 10 at an incident angle of 35 ° has, for example, a wavelength λ ⁵⁰ _{35 (UV)} having a transmittance of 50% in the wavelength range of 350 nm to 450 nm. Wavelength lambda ⁵⁰ ₃₅ absolute value [Delta] [lambda] ⁵⁰ of the difference between _(UV) and the first wavelength lambda ⁵⁰ _{0 (UV) 0/35 (UV)} is, for example, 8nm or less, desirably at 6nm or less, more preferably 4nm It is as follows.

The transmission spectrum of the light absorber 10 at an incident angle of 45 ° has, for example, a wavelength λ ⁵⁰ _{45 (IR) at} which the transmittance is 50% in the wavelength range of 650 nm to 750 nm. Wavelength lambda ⁵⁰ ₄₅ absolute value [Delta] [lambda] ⁵⁰ for the difference between the _(IR) and the second wavelength lambda ⁵⁰ _{0 (IR) 0/45 (IR)} is, for example, 18nm or less, preferably not more than 16 nm, more preferably 12nm It is as follows.

The transmission spectrum of the light absorber 10 at an incident angle of 35 ° has, for example, a wavelength λ ⁵⁰ _{35 (IR) at} which the transmittance is 50% in the wavelength range of 650 nm to 750 nm. Wavelength lambda ⁵⁰ ₃₅ absolute value [Delta] [lambda] ⁵⁰ for the difference between the _(IR) and the second wavelength lambda ⁵⁰ _{0 (IR) 0/35 (IR)} is, for example, 12nm or less, desirably at 10nm or less, and more preferably 8nm It is as follows.

The light absorber 10 typically contains a predetermined light absorber. The light absorber contained in the light absorber 10 is not limited to a specific substance as long as the transmission spectrum of the light absorber 10 at an incident angle of 0 ° satisfies the conditions (I) to (VI). The light absorber 10 contains, for example, a formed light-absorbing compound containing phosphonic acid and a copper component, and an ultraviolet absorber that absorbs at least a part of ultraviolet rays.

The phosphonic acid in the light-absorbing compound is not limited to a specific phosphonic acid as long as the transmission spectrum of the light absorber 10 at an incident angle of 0 ° satisfies the conditions (I) to (VI). The phosphonic acid is represented by, for example, the following formula (a). In formula (a), R ₁ is an alkyl group or an alkyl halide group in which at least one hydrogen atom in the alkyl group is substituted with a halogen atom. In this case, the transmission band of the light absorber 10 tends to extend to a wavelength of around 700 nm, and the light absorber 10 tends to have a desired transmittance characteristic.

Phosphonates include, for example, methylphosphonic acid, ethylphosphonic acid, normal (n-) propylphosphonic acid, isopropylphosphonic acid, normal (n-) butylphosphonic acid, isobutylphosphonic acid, sec-butylphosphonic acid, tert-butylphosphonic acid. , Or bromomethylphosphonic acid.

The light absorber 10 further contains, for example, at least one of an alkoxide having a metal component and a hydrolyzate of an alkoxide having a metal component. An alkoxide compound containing at least one of an alkoxide having a metal component and a hydrolyzate of an alkoxide having a metal component is, for example, a light-absorbing composition containing a curable compound to cure a fluid light-absorbing composition. When forming the light absorber 10, it can function as a catalyst for promoting the curing of the light-absorbing composition. When the light-absorbing composition is cured by heat treatment, the higher the temperature of the heat treatment, the easier it is to improve the environmental resistance such as heat resistance. On the other hand, if the temperature of the heat treatment is high, the characteristics of some UV absorbers may deteriorate. When the characteristics of the UV absorber deteriorate, the wavelength of the light absorbed by the UV absorber may deviate from the planned absorption wavelength. There is also the possibility that the absorption capacity of the UV absorber will decrease or disappear. However, when the light absorber 10 contains an alkoxide compound, it is possible to promote the curing of the light-absorbing composition even if the temperature of the heat treatment is not high. As a result, the light absorber 10 tends to have high environmental resistance.

The metal component contained in the alkoxide compound is not limited to a specific component. Examples of the metal component are, for example, Al, Ti, Zr, Zn, Sn, and Fe. As the alkoxide compound, for example, CAT-AC, DX-9740, D-20, D-25, DX-175, D-15, and D-31 can be used. All of these are products of Shin-Etsu Chemical Co., Ltd.

The ultraviolet absorber is not limited to a specific compound as long as the transmission spectrum of the light absorber 10 at an incident angle of 0 ° satisfies the conditions (I) to (VI). The ultraviolet absorber is, for example, a compound which does not have both a hydroxy group and a carbonyl group in the molecule, and is a compound which does not have both a hydroxy group and a carbonyl group in one molecule when expressed by a structural formula. be. Curing of the light-absorbing composition can be promoted by coordinating a reactant or a precursor at a specific position in a molecule such as an alkoxide having a metal component. For example, the presence of a group that is more likely to be coordinated by a substance other than the substance subjected to the reaction for curing the light-absorbing composition may weaken the action of the catalyst. In particular, both the hydroxy group and the carbonyl group have high electron donating properties, and the alkoxide compound reacts with or coordinates with an ultraviolet absorber having these groups, and a part of them forms a complex. , The inherent UV absorption characteristics of UV absorbers may change. However, when the UV absorber is a compound having neither a hydroxy group nor a carbonyl group in the molecule, the alkoxide compound is difficult to form a complex with the UV absorber, and the original UV absorption characteristics of the UV absorber are exhibited. Easy to be done. The ultraviolet absorber may contain only one of a hydroxy group and a carbonyl group in the molecule.

The UV absorber is preferably excellent in absorbing light in a desired wavelength range, having compatibility with a specific solvent, being well dispersed in a light-absorbing composition, and having excellent environmental resistance. It is selected from the viewpoint of things such as things. Examples of UV absorbers are benzophenone compounds, benzotriazole compounds, salicylic acid compounds, and triazine compounds. For example, as UV absorbers, TinuvinPS, Tinuvin99-2, Tinuvin234, Tinuvin326, Tinuvin329, Tinuvin900, Tinuvin928, Tinuvin405, and Tinuvin460 can be used. These are UV absorbers manufactured by BASF and Tinuvin is a registered trademark.

The light absorber 10 further contains, for example, a phosphoric acid ester. Due to the action of the phosphoric acid ester, the light-absorbing compound is easily dispersed appropriately in the light-absorbing body 10. The phosphoric acid ester may function as a dispersant for the light-absorbing compound, and a part thereof may react with a metal component to form a compound. For example, the phosphoric acid ester may be coordinated to a light-absorbing compound or reacted with the compound, or may form a partial complex with a copper component.

The phosphoric acid ester is not limited to a specific phosphoric acid ester. The phosphoric acid ester has, for example, a polyoxyalkyl group. Examples of such a phosphoric acid ester include plysurf A208N: polyoxyethylene alkyl (C12, C13) ether phosphoric acid ester, plysurf A208F: polyoxyethylene alkyl (C8) ether phosphoric acid ester, and plysurf A208B: polyoxyethylene. Lauryl Ether Phosphate, Plysurf A219B: Polyoxyethylene Lauryl Ether Phosphate, Plysurf AL: Polyoxyethylene Stylized Phylether Phosphate, Plysurf A212C: Polyoxyethylene Tridecyl Ether Phosphate, or Ply Surf A215C: Polyoxyethylene tridecyl ether phosphate ester can be mentioned. All of these are products manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd. In addition, as the phosphoric acid ester, NIKKOL DDP-2: polyoxyethylene alkyl ether phosphoric acid ester, NIKKOL DDP-4: polyoxyethylene alkyl ether phosphoric acid ester, or NIKKOL DDP-6: polyoxyethylene alkyl ether phosphoric acid ester. Can be mentioned. All of these are products manufactured by Nikko Chemicals.

The light absorber 10 further contains, for example, a resin. The resin is not limited to a specific resin as long as the transmission spectrum of the light absorber 10 at an incident angle of 0 ° satisfies the conditions (I) to (VI). Examples of the resin are a cyclic polyolefin resin, an epoxy resin, a polyimide resin, a modified acrylic resin, a silicone resin, and a polyvinyl resin such as PVB. The resin in the light-absorbing film 10 can be a cured product of a curable resin that can be cured by irradiation with energy such as heat or light.

The content of phosphonic acid and phosphoric acid ester in the light absorber 10 is not limited to a specific value. The ratio of the content of phosphonic acid to the content of phosphoric acid in the light absorber 10 is, for example, 1.0 to 3.0 on a mass basis. As a result, even if the light absorber 10 comes into contact with water vapor, hydrolysis of the phosphoric acid ester is suppressed, and the light absorber 10 tends to have good weather resistance.

The ratio of the content of the copper component to the content of the phosphorus component derived from the phosphonic acid and the phosphoric acid ester is not limited to a specific value. The ratio is, for example, 1 to 3 on a mass basis, preferably 1.5 to 2.

The content of the alkoxide compound in the light absorber 10 is not limited to a specific value. As described above, the alkoxide compound acts as a catalyst for promoting the curing of the light-absorbing composition. The inclusion of a small amount of the alkoxide compound in the light-absorbing composition can exert this catalytic action. The ratio of the content of the phosphorus component to the content of the metal component in the alkoxide compound is, for example, 5 to 5000, preferably 50 to 500 on a mass basis. The phosphorus component is typically derived from light-absorbing compounds and phosphate esters. On the other hand, the ratio of the content of the copper component to the content of the metal component in the alkoxide compound is, for example, 10 to 10000, preferably 100 to 1000.

The content of the ultraviolet absorber in the light absorber 10 is not limited to a specific value as long as the transmission spectrum of the light absorber 10 at an incident angle of 0 ° satisfies the conditions (I) to (VI). High absorption capacity can be exhibited by containing a small amount of UV absorber. The ratio of the content of the ultraviolet absorber to the content of the copper component in the light absorber 10 is, for example, 0.01 to 1, preferably 0.02 to 0.5, and more preferably 0 on a mass basis. It is .07 to 0.14. The ratio of the content of the ultraviolet absorber to the content of the phosphorus component in the light absorber 10 is, for example, 0.02 to 2, preferably 0.04 to 1, and more preferably 0.12 on a mass basis. ~ 0.26.

As shown in FIG. 1, the light absorber 10 is, for example, in the form of a film. As used herein, "membrane" is synonymous with coating or layer. The light absorber 10 is not limited to the film shape.

The thickness of the light absorber 10 is not limited to a specific value as long as the transmission spectrum of the light absorber 10 at an incident angle of 0 ° satisfies the conditions (I) to (VI). The thickness of the light absorber 10 is, for example, 500 μm or less, preferably 250 μm or less, more preferably 150 μm or less, and further preferably 100 μm or less. The small thickness of the light absorber 10 is advantageous from the viewpoint of lowering the height of the image pickup apparatus provided with the light absorber 10.

The light absorber 10 can be produced, for example, by curing a predetermined light-absorbing composition.

The light-absorbing composition is not limited to a specific composition as long as the transmission spectrum of the light absorber 10 at an incident angle of 0 ° satisfies the conditions (I) to (VI). The light-absorbing composition contains, for example, a light-absorbing compound containing phosphonic acid and a copper component, and an ultraviolet absorber that absorbs at least a part of ultraviolet rays. Regarding the light-absorbing compound, the description of the light-absorbing compound in the light-absorbing body 10 can be referred to.

The light-absorbing composition further contains, for example, at least one alkoxide having a metallic component and a hydrolyzate of an alkoxide having a metallic component. Regarding the alkoxide having a metal component and the hydrolyzate of the alkoxide having a metal component, the description of the alkoxide compound in the light absorber 10 can be referred to.

As long as the transmission spectrum of the light absorber 10 at an incident angle of 0 ° satisfies the conditions (I) to (VI), the ultraviolet absorber in the light-absorbing composition is not limited to a specific compound. As an example of the ultraviolet absorber, the description of the ultraviolet absorber in the light absorber 10 can be referred to. The UV absorber is, for example, a compound that does not contain both a hydroxy group and a carbonyl group in the molecule. That is, the ultraviolet absorber may be a compound containing only one of a hydroxy group and a carbonyl group.

The light-absorbing composition further contains, for example, a phosphate ester. This makes it easy for the light-absorbing compound to be appropriately dispersed in the light-absorbing composition. Regarding the phosphoric acid ester, the description of the phosphoric acid ester in the light absorber 10 can be referred to.

The light-absorbing composition further contains, for example, a curable resin. Regarding the curable resin, the description of the resin in the light absorber 10 can be referred to.

In the preparation of the light-absorbing composition, the source of the copper component in the light-absorbing compound is not limited to a specific substance. The source of the copper component is, for example, a copper salt. The copper salt may be an anhydride or hydrate of copper chloride, copper formate, copper stearate, copper benzoate, copper pyrophosphate, copper naphthenate, and copper citrate. For example, copper acetate monohydrate is _{represented as Cu (CH 3} COO) ₂ · H ₂ O, and 1 mol of copper ion is supplied by 1 mol of copper acetate monohydrate.

For example, a member having the light absorber 10 formed on the surface of the article can be used as an optical filter. In addition, the light absorber 10 itself can be independently used as an optical filter by forming the light absorber 10 on the surface of the article and then peeling it off. The method for producing the light absorber 10 is not limited to a specific method. The light absorber 10 may be manufactured by a method such as casting (casting), compression molding, vacuum forming, press molding, injection molding, blow molding, or extrusion molding.

As shown in FIG. 1A, the light absorber 10 may be used alone. On the other hand, as shown in FIG. 1B, the article 1a with a light absorber can be provided. The article 1a with a light absorber includes an article 20 and a light absorber 10. The light absorber 10 covers at least a part of the surface of the article 20.

The shape of the article 20 in the article 1a with a light absorber is not limited to a specific shape. The article 20 may be a flat plate-shaped member or a substrate. Article 20 is not limited to a specific article. Article 20 is, for example, an optical element (including an acoustic optical element) such as a lens, a mirror, a prism, a diffuser, a flat plate microlens array, a polarizing element, a diffraction grating, a hologram, a light modulation element, a light deflection element, and a filter. You may. The article 20 may be a solid-state imaging device, a window or windshield of a building or an automobile, a light-transmitting shield such as a helmet, and goggles, or a display device such as a display and a screen. The surface of the article 20 covered by the light absorber 10 may be a flat surface, a curved surface, or a surface having irregularities.

The light absorber 10 may be obtained by molding an optical element such as a lens using the light-absorbing composition. In this case, the light absorber 10 may be used alone.

As shown in FIG. 1C, the dielectric multilayer film 30 may be formed on the article 1a with a light absorber. In addition, as shown in FIG. 1D, the dielectric multilayer film 30 may be formed on the light absorber 10. In the dielectric multilayer film 30, two or more kinds of dielectrics having different refractive indexes such as _{SiO 2} , TiO ₂ , MgF ₂ , and Ta ₂ O _{5 are laminated alternately.} The dielectric multilayer film 30 can exhibit light reflectivity or light antireflection property. The light shielding function may be exhibited by the cooperation between the light absorber 10 and the dielectric multilayer film 30. For example, when the dielectric multilayer film 30 has light reflectivity, the burden required for the light absorber 10 with respect to the light absorption characteristics can be reduced. Therefore, for example, the thickness of the light absorber 10 can be reduced. It is also possible to reduce the content of the light-absorbing composition or the content of the ultraviolet absorber in the light-absorbing body 10.

An apparatus including the light absorber 10 can be provided. The use of such a device is not limited to a specific use. Such devices are, for example, in-vehicle cameras and in-vehicle sensors. In this case, since the light absorber 10 has a predetermined ultraviolet absorption property, the image pickup element and the sensor element can be protected from ultraviolet rays. Further, since the light absorber 10 has a high transmittance in the vicinity of a wavelength of 700 nm, the light absorber 10 can be used in a sensing system such as a light detection and ranging (Lidar) system using an infrared ray or a red laser. Since the light absorber 10 has a particularly high transparency of light belonging to red, the ability of the device provided with the light absorber 10 to recognize an object such as a red light and a road sign tends to be high. In addition, since the light absorber 10 shields light in a specific wavelength region by absorption, ghosts and flares can be suppressed in a device provided with the light absorber 10. Further, the lidar system can be installed not only in in-vehicle devices but also in portable information terminals such as smartphones.

As shown in FIG. 2, for example, an image pickup apparatus 100 provided with a light absorber 10 can be provided. The image pickup device 100 further includes, for example, a lens system 40 and an image pickup element 50. The light absorber 10 is arranged, for example, between the lens system 40 and the image pickup device 50. The application target of the image pickup apparatus 100 is not limited to a specific product. The image pickup device 100 is incorporated into, for example, a camera module mounted on a portable information terminal such as a smartphone, a device incorporated in an in-vehicle sensing module, and a sensing module in an unmanned aerial vehicle or an unmanned surface boat (USV) such as a drone. It can be applied as a device. The light absorber 10 may be applied to an ambient light sensor for detecting the brightness of the surroundings of a device or the like on which the light absorber 10 is mounted.

The present invention will be described in more detail by way of examples. The present invention is not limited to the following examples. First, an evaluation method of an optical filter according to each example and each comparative example will be described.

(Transmission spectrum measurement)
Using an ultraviolet-visible near-infrared spectrophotometer V-670 manufactured by JASCO Corporation, the transmission spectra of the optical filters according to each embodiment were measured at incident angles of 0 °, 35 °, 45 °, and 55 °. The results are shown in FIGS. 3A-5C. On the other hand, in the same manner, the transmission spectrum of the optical filter according to each comparative example at an incident angle of 0 ° was measured. The results are shown in FIGS. 6 to 9. Table 3 shows the characteristic values of each optical filter taken from these transmission spectra. The subscript "IA" in each item in Table 3 indicates the incident angle [°].

(Thickness measurement)
The thickness of the optical filter was measured using a laser displacement meter LK-H008 manufactured by KEYENCE. The results are shown in Table 3.

<Example 1>
4.500 g of copper acetate monohydrate and 240 g of tetrahydrofuran (THF) were mixed and stirred for 3 hours to obtain a copper acetate solution. Next, 2.572 g of the phosphoric acid ester compound Plysurf A208N manufactured by Daiichi Kogyo Seiyaku Co., Ltd. was added to the obtained copper acetate solution and stirred for 30 minutes to obtain a solution A. Further, 40 g of THF was added to 2.886 g of n-butylphosphonic acid and stirred for 30 minutes to obtain a liquid B. Liquid B was added to liquid A while stirring liquid A, and the mixture was stirred at room temperature for 1 minute. Next, 100 g of toluene was added to this solution, and the mixture was stirred at room temperature for 1 minute to obtain a solution C. This liquid C is placed in a flask and heated in an oil bath (manufactured by Tokyo Rika Kikai Co., Ltd., model: OSB-2100) while being desolvated by a rotary evaporator (manufactured by Tokyo Rika Kikai Co., Ltd., model: N-1110SF). gone. The set temperature of the oil bath was adjusted to 105 ° C. Then, the liquid D after the desolvation treatment was taken out from the flask. In this way, a composition α containing a compound formed by the phosphonic acid and the copper component was obtained. It was speculated that the compound formed by the phosphonic acid and the copper component was dispersed as fine particles in the composition.

BASF's benzotriazole-based UV absorber Tinuvin326 was added to 95 g of toluene in an amount of 5 g, and the mixture was stirred for 30 minutes to obtain a composition β-1 containing a UV absorber. In addition, Tinuvin326 contains 2- [5-Chloro- (2H) -Benzotriazol-2-yl] -4-methyl-6- (tert-butyl) phenol represented by the following formula (b-1). board.

The composition α, 2.0 g of the composition β-1, and 0.09 g of the aluminum alkoxide compound CAT-AC manufactured by Shin-Etsu Chemical Co., Ltd. were added to 8.80 g of the silicone resin KR-300 manufactured by Shin-Etsu Chemical Co., Ltd. Then, the mixture was stirred for 30 minutes to obtain a light-absorbing composition according to Example 1. Table 1 shows the amount of the material added in the preparation of the light-absorbing composition or the content of the predetermined component in the light-absorbing composition. Table 2 shows the ratio of the content of the components. The average molecular weight of Plysurf A208N used as a phosphoric acid ester was determined to be 632 g / mol.

0.1 g of the surface antifouling coating agent Optool DSX (concentration of active ingredient: 20% by mass) manufactured by Daikin Industries, Ltd. and 19.9 g of Hydrofluoroether-containing liquid Novec 7100 manufactured by 3M Co., Ltd. are mixed and stirred for 5 minutes. Then, a fluorinated agent (concentration of active ingredient: 0.1% by mass) was prepared. This fluorinated agent was applied to borosilicate glass (manufactured by SCHOTT, product name: D263 Teco) having dimensions of 130 mm × 100 mm × 0.70 mm by a flow coat method. Then, the glass substrate was left at room temperature for 24 hours to dry the coating film of the fluorinated agent, and then the glass surface was lightly wiped with a dust-free cloth containing Novec 7100 to remove the excess fluorinated agent. In this way, the fluorine-treated substrate was produced.

The light-absorbing composition according to Example 1 was applied to a range of 80 mm × 80 mm in the center of one main surface of the fluorine-treated substrate using a dispenser to form a coating film. After the obtained coating film is sufficiently dried at room temperature, it is placed in an oven and the solvent is volatilized while slowly raising the temperature in the range of room temperature to 45 ° C. to proceed with drying, and finally at 85 ° C. for 6 hours. A heat treatment was performed to completely volatilize the solvent and cure it. After that, the coating film was peeled off from the fluorine-treated substrate to obtain an optical filter according to Example 1 composed of a film-shaped light absorber. The transmission spectra of the optical filter according to Example 1 at the incident angles of 0 ° and 35 °, the incident angles of 0 ° and 45 °, and the incident angles of 0 ° and 55 ° are shown in FIGS. 3A, 3B, and 3C, respectively. ..

<Example 2>
As an ultraviolet absorber, 5.0 g of BASF's benzotriazole-based ultraviolet absorber Tinuvin234 was added to 95.0 g of toluene and stirred for 30 minutes to prepare a composition β-2 containing an ultraviolet absorber. Tinuvin234 contained Phenol, 2- (2H-Benzotriazol-2-yl) -4,6-bis (1-methyl-1-Phenylethyl) represented by the following formula (b-2). Light according to Example 2 in the same manner as in Example 1 except that 3.6 g of the composition β-2 was added instead of 2.0 g of the composition β-1 in the preparation of the light-absorbing composition. An absorbent composition was prepared. Table 1 shows the amount of the material added in the preparation of the light-absorbing composition or the content of the predetermined component in the light-absorbing composition. Table 2 shows the ratio of the content of the components.

Optical according to Example 2 composed of a film-shaped light absorber in the same manner as in Example 1 except that the light-absorbing composition according to Example 2 was used instead of the light-absorbing composition according to Example 1. A filter was made. The transmission spectra of the optical filter according to Example 1 at the incident angles of 0 ° and 35 °, the incident angles of 0 ° and 45 °, and the incident angles of 0 ° and 55 ° are shown in FIGS. 4A, 4B, and 4C, respectively. ..

<Example 3>
As an ultraviolet absorber, 5.0 g of BASF's benzotriazole-based ultraviolet absorber Tinuvin329 was added to 95.0 g of toluene and stirred for 30 minutes to prepare a composition β-3 containing an ultraviolet absorber. Tinuvin329 contained 2Phenol, 2- (2H-Benzotriazol-2-yl) -4- (1,1,3,3-tetramethylbutyl) represented by the following formula (b-3). Light according to Example 3 in the same manner as in Example 1 except that 4.0 g of the composition β-3 was added instead of 2.0 g of the composition β-1 in the preparation of the light-absorbing composition. An absorbent composition was prepared. Table 1 shows the amount of the material added in the preparation of the light-absorbing composition or the content of the predetermined component in the light-absorbing composition. Table 2 shows the ratio of the content of the components.

Optical according to Example 3 comprising a film-shaped light absorber in the same manner as in Example 1 except that the light-absorbing composition according to Example 3 was used instead of the light-absorbing composition according to Example 1. A filter was made. The transmission spectra of the optical filter according to Example 3 at the incident angles of 0 ° and 35 °, the incident angles of 0 ° and 45 °, and the incident angles of 0 ° and 55 ° are shown in FIGS. 5A, 5B, and 5C, respectively. ..

<Comparative Example 1>
The light-absorbing composition according to Comparative Example 1 was prepared in the same manner as in Example 1 except that the composition β-1 was not added. Table 1 shows the amount of the material added in the preparation of the light-absorbing composition or the content of the predetermined component in the light-absorbing composition. Table 2 shows the ratio of the content of the components.

Optical according to Comparative Example 1 composed of a film-shaped light absorber in the same manner as in Example 1 except that the light-absorbing composition according to Comparative Example 1 was used instead of the light-absorbing composition according to Example 1. A filter was made. FIG. 6 shows the transmission spectrum of the optical filter according to Comparative Example 1 at an incident angle of 0 °.

<Comparative Example 2>
As an ultraviolet absorber, 2.0 g of Uvinul3049, a hydroxybenzophenone-based ultraviolet absorber manufactured by BASF, was added to 98.0 g of toluene and stirred for 30 minutes to prepare a composition β-4 containing an ultraviolet absorber. Uvinul3049 contained a compound represented by the following formula (b-4). Light according to Comparative Example 2 in the same manner as in Example 1 except that 5.0 g of the composition β-4 was added instead of 2.0 g of the composition β-1 in the preparation of the light-absorbing composition. An absorbent composition was prepared. Table 1 shows the amount of the material added in the preparation of the light-absorbing composition or the content of the predetermined component in the light-absorbing composition. Table 2 shows the ratio of the content of the components.

Optical according to Comparative Example 2 composed of a film-shaped light absorber in the same manner as in Example 1 except that the light-absorbing composition according to Comparative Example 2 was used instead of the light-absorbing composition according to Example 1. A filter was made. FIG. 7 shows the transmission spectrum of the optical filter according to Comparative Example 2 at an incident angle of 0 °.

<Comparative Example 3>
2.0 g of the UV absorber Uvinul3049 was added to 98.0 g of toluene and stirred for 30 minutes to prepare a composition containing the UV absorber. 5.0 g of this composition was added to 10.0 g of a silicone resin KR-300 manufactured by Shin-Etsu Chemical Co., Ltd. and stirred for 30 minutes to obtain a light-absorbing composition according to Comparative Example 3. Table 1 shows the amount of the material added in the preparation of the light-absorbing composition or the content of the predetermined component in the light-absorbing composition. Table 2 shows the ratio of the content of the components.

Optical according to Comparative Example 3 composed of a film-shaped light absorber in the same manner as in Example 1 except that the light-absorbing composition according to Comparative Example 3 was used instead of the light-absorbing composition according to Example 1. A filter was made. FIG. 8 shows the transmission spectrum of the optical filter according to Comparative Example 3 at an incident angle of 0 °.

<Comparative Example 4>
2.0 g of the UV absorber Uvinul3049 was added to 98.0 g of toluene and stirred for 30 minutes to prepare a composition containing the UV absorber. 5.0 g of this composition and 0.10 g of aluminum alkoxide CAT-AC manufactured by Shin-Etsu Chemical Co., Ltd. were added to 10.0 g of silicone resin KR-300 manufactured by Shin-Etsu Chemical Co., Ltd. and stirred for 30 minutes for comparison. A light-absorbing composition according to Example 4 was obtained. Table 1 shows the amount of the material added in the preparation of the light-absorbing composition or the content of the predetermined component in the light-absorbing composition. Table 2 shows the ratio of the content of the components.

Optical according to Comparative Example 4 composed of a film-shaped light absorber in the same manner as in Example 1 except that the light-absorbing composition according to Comparative Example 4 was used instead of the light-absorbing composition according to Example 1. A filter was made. FIG. 9 shows the transmission spectrum of the optical filter according to Comparative Example 4 at an incident angle of 0 °.

As shown in Table 3, according to the transmission spectra of the optical filters according to each embodiment, these optical filters had desired transmittance characteristics. On the other hand, according to the transmission spectrum of the optical filter according to Comparative Example 1 at an incident angle of 0 °, the wavelength λ ⁵⁰⁰ _(UV) at which the transmittance is 50% in the wavelength range of 350 nm to 450 nm is 354 nm, and T ^M _(350-370) was more than 70%. Therefore, it cannot be said that the optical filter according to Comparative Example 1 has desired transmittance characteristics.

According to the transmission spectrum of the optical filter according to Comparative Example 2 at an incident angle of 0 °, λ ⁵⁰⁰ _(UV) was 443 nm. Therefore, it cannot be said that the optical filter according to Comparative Example 2 has desired transmittance characteristics. The ultraviolet absorber Uvinul3049 used for producing the optical filter according to Comparative Example 2 contains both hydroxy and carbonyl groups in the molecule, and serves as a catalyst, an alkoxide compound containing a metal component, and ultraviolet rays. It is presumed that the original absorption wavelength of the ultraviolet absorber was shifted to the long wavelength side due to a partial reaction with the absorber.

Comparative Examples 3 and 4 are examples for examining what kind of difference occurs in the transmission spectrum of the optical filter depending on the presence or absence of aluminum alkoxide in the light-absorbing composition. The difference in the light absorption characteristics due to the optical filters according to Comparative Examples 3 and 4 appeared particularly at the wavelength λ ⁵⁰⁰ _(UV) where the transmittance was 50% in the wavelength range of 350 nm to 450 nm. In the optical filter according to Comparative Example 4 containing both the ultraviolet absorber and the aluminum alkoxide, the wavelength λ ⁵⁰⁰ _(UV) was 444 nm. On the other hand, in the optical filter according to Comparative Example 3 containing no aluminum alkoxide, the wavelength λ ⁵⁰⁰ _(UV) was 400 nm. From these results, it is inherent in the ultraviolet absorber that an ultraviolet absorber containing both hydroxy and carbonyl groups in the molecule is contained together with an alkoxide compound containing a metal component such as aluminum alkoxide. It is understood that the properties change.

1a Article with light absorber 10 Light absorber 20 Article 30 Dielectric multilayer film 40 Lens system 50 Image sensor 100 Image sensor

Claims (18)

A light absorber whose transmission spectrum at an incident angle of 0 ° satisfies the following conditions (I), (II), (III), (IV), (V), and (VI).
(I) The average value of the transmittance in the wavelength range of 450 nm to 600 nm is 75% or more.
(II) The first wavelength having a transmittance of 50% in the wavelength range of 350 nm to 450 nm is 380 nm or more and 440 nm or less.
(III) The second wavelength having a transmittance of 50% in the wavelength range of 650 nm to 750 nm is 680 nm or more and 740 nm or less.
(IV) The maximum value of the transmittance in the wavelength range of 350 nm to 370 nm is 1% or less.
(V) The maximum value of the transmittance in the wavelength range of 800 nm to 900 nm is 5% or less.
(VI) The maximum value of the transmittance in the wavelength range of 1100 nm to 1200 nm is 5% or less. The light absorber according to claim 1, wherein the transmission spectrum further satisfies the following condition (VII).
(VII) The transmittance at a wavelength of 750 nm is 7% or more. The light absorber according to claim 1 or 2, wherein the transmission spectrum further satisfies the following condition (VIII).
(VIII) The transmittance at a wavelength of 780 nm is 3% or more. The transmission spectrum of the light absorber at an incident angle of 55 ° has a third wavelength having a transmittance of 50% in the wavelength range of 350 nm to 450 nm.
The absolute value of the difference between the third wavelength and the first wavelength is 12 nm or less.
The light absorber according to any one of claims 1 to 3. The transmission spectrum of the light absorber at an incident angle of 55 ° has a fourth wavelength having a transmittance of 50% in the wavelength range of 650 nm to 750 nm.
The absolute value of the difference between the fourth wavelength and the second wavelength is 24 nm or less.
The light absorber according to any one of claims 1 to 4. A light-absorbing compound containing phosphonic acid and a copper component,
Contains an ultraviolet absorber that absorbs at least part of the ultraviolet light,
The light absorber according to any one of claims 1 to 5. The light absorber according to claim 6, further comprising at least one of an alkoxide having a metal component and a hydrolyzate of an alkoxide having a metal component. The light absorber according to claim 7, wherein the ultraviolet absorber is a compound having neither a hydroxy group nor a carbonyl group in the molecule. Goods and
The light absorber according to any one of claims 1 to 8, which is formed on a part of the surface of the article.
Article with light absorber. An image pickup apparatus comprising the light absorber according to any one of claims 1 to 8. A light-absorbing composition
The transmission spectra of the light absorber obtained by curing the light-absorbing composition at an incident angle of 0 ° are as follows (i), (ii), (iii), (iv), (v), and (vi). A light-absorbing composition that satisfies the above conditions.
(I) The average value of the transmittance in the wavelength range of 450 nm to 600 nm is 75% or more.
(Ii) The first wavelength having a transmittance of 50% in the wavelength range of 350 nm to 450 nm is 380 nm or more and 440 nm or less.
(Iii) The second wavelength having a transmittance of 50% in the wavelength range of 650 nm to 750 nm is 680 nm or more and 740 nm or less.
(Iv) The maximum value of the transmittance in the wavelength range of 350 nm to 370 nm is 1% or less.
(V) The maximum value of the transmittance in the wavelength range of 800 nm to 900 nm is 5% or less.
(Vi) The maximum value of the transmittance in the wavelength range of 1100 nm to 1200 nm is 5% or less. The light-absorbing composition according to claim 11, wherein the transmission spectrum further satisfies the following condition (vii).
(Vii) The transmittance at a wavelength of 750 nm is 7% or more. The light-absorbing composition according to claim 11 or 12, wherein the transmission spectrum further satisfies the following condition (viii).
(Viii) The transmittance at a wavelength of 780 nm is 3% or more. The transmission spectrum of the light absorber at an incident angle of 55 ° has a third wavelength having a transmittance of 50% in the wavelength range of 350 nm to 450 nm.
The absolute value of the difference between the third wavelength and the first wavelength is 12 nm or less.
The light-absorbing composition according to any one of claims 11 to 13. The transmission spectrum of the light absorber at an incident angle of 55 ° has a fourth wavelength having a transmittance of 50% in the wavelength range of 650 nm to 750 nm.
The absolute value of the difference between the fourth wavelength and the second wavelength is 24 nm or less.
The light-absorbing composition according to any one of claims 11 to 14. A light-absorbing compound containing phosphonic acid and a copper component,
Contains an ultraviolet absorber that absorbs at least part of the ultraviolet light,
The light-absorbing composition according to any one of claims 11 to 15. The light-absorbing composition according to claim 16, further comprising at least one of an alkoxide having a metallic component and a hydrolyzate of an alkoxide having a metallic component. The light-absorbing composition according to claim 17, wherein the ultraviolet absorber is a compound having neither a hydroxy group nor a carbonyl group in the molecule.

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