CN115113314A

CN115113314A - Substrate, optical filter and use thereof

Info

Publication number: CN115113314A
Application number: CN202210242252.XA
Authority: CN
Inventors: 安藤嘉彦; 茂木武志
Original assignee: JSR Corp
Current assignee: JSR Corp
Priority date: 2021-03-17
Filing date: 2022-03-11
Publication date: 2022-09-27
Also published as: TW202237749A; JP2022145519A; KR20220130030A

Abstract

The invention provides a substrate suitable for an optical filter, an optical filter and use thereof. The optical filter is excellent in optical characteristics such as near-infrared shielding property and heat resistance, can be further thinned, and is less likely to cause warpage or cracking. A substrate has a layer containing nanofibers and has an absorption maximum wavelength in the range of 600nm to 1200nm in wavelength.

Description

Substrate, optical filter and use thereof

Technical Field

The present invention relates to a substrate suitable for an optical filter, an optical filter comprising said substrate and uses thereof.

Background

In solid-state imaging devices such as video cameras, digital still cameras, and mobile phones with camera functions, Charge Coupled Devices (CCDs) or Complementary Metal Oxide Semiconductor (CMOS) image sensors are used as solid-state imaging elements for color images. In these solid-state imaging elements, silicon photodiodes (silicon photodiodes) having sensitivity to near infrared rays that cannot be perceived by human eyes are used for their light-receiving sections. In addition, a silicon photodiode or the like is also used in the optical sensor device. For example, in a solid-state imaging device, it is necessary to perform visibility correction that presents natural color when viewed by the human eye, and an optical filter (for example, a near infrared ray cut filter) that selectively transmits or cuts light in a specific wavelength region is often used.

As such a near infrared ray cut filter, filters manufactured by various methods have been used from the beginning. For example, a near-infrared cut filter using a resin as a base material and containing a near-infrared absorbing dye in the resin (for example, see patent document 1) and an absorbing glass type optical filter in which copper oxide is dispersed in phosphate glass (for example, see patent document 2) are known.

However, the near-infrared cut filter described in patent document 1 may not have sufficient near-infrared absorption characteristics.

In recent years, there has been a demand for a thin solid-state imaging device, and also for an optical filter to be used. However, there are problems as follows: when the thickness of the optical filter is reduced, warping or cracking is likely to occur. Further, there is a demand for a reduction in thickness and an improvement in heat resistance of an optical filter.

[ Prior art documents ]

[ patent document ]

[ patent document 1] Japanese patent laid-open No. Hei 6-200113

[ patent document 2] International publication No. 2011/071157

Disclosure of Invention

[ problems to be solved by the invention ]

In view of the problems of the conventional techniques, an object of the present invention is to provide a substrate suitable for an optical filter which is excellent in optical characteristics such as near infrared ray shielding property and heat resistance, can be further thinned, and is less likely to cause warpage or cracking, an optical filter including the substrate, and a solid-state imaging device and a camera module including the optical filter.

[ means for solving problems ]

The present inventors have made extensive studies to solve the above problems, and as a result, have found that the above problems can be solved by the following configuration examples, and have completed the present invention. The following shows a configuration example of the present invention.

[1] A substrate has a layer containing nanofibers and has an absorption maximum wavelength in the range of 600nm to 1200nm in wavelength.

[2] The substrate according to item [1], wherein the nanofibers have an average fiber diameter of 3 to 200nm and an average fiber length of 0.2 to 10 μm.

[3]According to item [1]Or item [2]]The substrate described above, wherein the nanofibers have a specific surface area of 70m ² /g～300m ² /g。

[4] The substrate according to any one of items [1] to [3], wherein the nanofiber has a crystallinity of 43% or more.

[5] The substrate according to any one of items [1] to [4], wherein the nanofibers are hydrophobic cellulose nanofibers dispersible in an organic solvent.

[6] The base material according to any one of items [1] to [5], comprising a resin substrate containing the nanofibers and a compound (A) having an absorption maximum wavelength in a range of 600nm to 1200 nm.

[7] The base material according to item [6], wherein the content of the nanofibers is 5 to 50 parts by mass, assuming that the total content of the resin constituting the resin substrate and the nanofibers is 100 parts by mass.

[8] The substrate according to any one of item [1] to item [5], comprising: a substrate selected from a resin substrate and a near-infrared-absorbing glass substrate containing a compound (A) having an absorption maximum wavelength in a range of 600nm to 1200 nm; and resin layers formed on both surfaces of the substrate and containing the nanofibers.

[9] The substrate according to any one of item [1] to item [5], comprising: a support made of resin or glass; and resin layers formed on both surfaces of the support, and containing the nanofibers and a compound (A) having an absorption maximum wavelength in the range of 600nm to 1200 nm.

[10] The base material according to item [8] or item [9], wherein the content of the nanofibers is 5 to 70 parts by mass, assuming that the total of the contents of the resin constituting the resin layer and the nanofibers is 100 parts by mass.

[11] The base material according to any one of items [6] to [8], wherein the resin constituting the resin substrate is selected from the group consisting of cyclic polyolefin resins, aromatic polyether resins, polyimide resins, fluorene polycarbonate resins, fluorene polyester resins, polycarbonate resins, polyamide resins, aromatic polyamide resins, polysulfone resins, polyethersulfone resins, polyphenylene resins, polyamideimide resins, polyethylene naphthalate resins, fluorinated aromatic polymer resins, (modified) acrylic resins, epoxy resins, silsesquioxane ultraviolet-curing resins, maleimide resins, alicyclic epoxy thermosetting resins, polyether ether ketone resins, polyarylate resins, allyl-curing resins, acrylic ultraviolet-curing resins, vinyl-curing resins, and resins containing silica as a main component formed by a sol-gel method At least one resin of the group.

[12] The base material according to item [9] or item [10], wherein the resin constituting the resin layer is selected from the group consisting of a cyclic polyolefin resin, an aromatic polyether resin, a polyimide resin, a fluorene polycarbonate resin, a fluorene polyester resin, a polycarbonate resin, a polyamide resin, an aromatic polyamide resin, a polysulfone resin, a polyethersulfone resin, a polyphenylene resin, a polyamideimide resin, a polyethylene naphthalate resin, a fluorinated aromatic polymer resin, (modified) acrylic resin, an epoxy resin, a silsesquioxane ultraviolet-curing resin, a maleimide resin, an alicyclic epoxy thermosetting resin, a polyether ether ketone resin, a polyarylate resin, an allyl ester curing resin, an acrylic ultraviolet-curing resin, a vinyl ultraviolet-curing resin, and a resin containing silica as a main component formed by a sol-gel method At least one resin of (a).

[13] An optical filter comprising the substrate according to any one of items [1] to [12], and a dielectric multilayer film.

[14] The optical filter according to item [13], having a thickness of 150 μm or less.

[15] An image pickup apparatus comprising the optical filter according to the item [13] or the item [14 ].

[16] A camera module comprising the optical filter according to item [13] or item [14 ].

[ Effect of the invention ]

According to the present invention, an optical filter excellent in optical characteristics such as near infrared ray shielding property, further reduced in thickness, and excellent in low warpage property and heat resistance, a base material suitable for the optical filter, and a solid-state imaging device and a camera module including the optical filter can be provided.

Drawings

Fig. 1 (a), 1 (b) and 1 (c) are schematic views showing examples of the form of the base material of the present invention.

[ description of symbols ]

1 a: resin substrate containing compound (A) and nanofibers

1 b: substrate containing Compound (A)

1 c: resin support or glass support

2 a: resin layer

2 b: resin layer containing nanofibers

2 c: resin layer containing compound (A) and nanofiber

Detailed Description

Embodiments of the base material and the optical filter of the present invention will be described below with reference to the drawings and the like. However, the present invention can be implemented in a plurality of different forms, and is not to be construed as being limited to the description of the embodiments illustrated below. In order to more clearly explain the drawings, the width, thickness, shape, and the like of each part may be schematically shown as compared with the actual form, but the drawings are merely examples and do not limit the explanation of the present invention. In the description and the drawings, the same or similar elements as those described above are denoted by the same reference numerals (only a reference numeral such as ""' "is given after the reference numeral), and detailed description thereof may be omitted as appropriate.

In the present invention, the description of "a to B" and the like indicating a numerical range is the same as "a or more and B or less", and a and B are included in the numerical range. In the present invention, the wavelength A nm to B nm means a characteristic of a wavelength resolving power of 1nm in a wavelength region of a wavelength A nm or longer and a wavelength B nm or shorter.

< substrate >

The substrate of the present invention has a layer containing nanofibers as described later, and the absorption maximum wavelength is in the range of 600nm to 1200 nm. The base material of the present invention is not particularly limited in material, shape, and the like, as long as the effect of the present invention is not impaired, and a plate-like body having transparency is preferable. Examples of the material of such a substrate include various glasses and resins.

The base material may be a single layer or a plurality of layers, and may comprise one material selected from the above materials, a plurality of materials, or a mixture of materials.

As a preferred embodiment of the substrate, there can be mentioned

Form (i) comprising a resin substrate containing the nanofibers and a compound (A) having an absorption maximum wavelength in the range of 600nm to 1200 nm;

form (ii), comprising: a substrate selected from a resin substrate and a near-infrared-absorbing glass substrate containing the compound (A); and resin layers formed on both sides of the substrate and containing the nanofibers;

form (iii) comprising: a support made of resin or glass; and a resin layer formed on both surfaces of the support and containing the nanofibers and the compound (A).

In addition, the nanofibers and the compound (a) may be contained in the same layer, or may be contained in different layers.

In the above aspect (i), a resin layer such as an overcoat layer containing a curable resin or the like may be laminated on at least one surface of the resin substrate as necessary. Fig. 1 (a) shows an example of a substrate in the form (i) in which the resin substrate 1a containing the nanofibers and the compound (a) has overcoats (resin layers) 2a on both surfaces thereof. Fig. 1 (b) shows an example of the form in which the base material of the form (ii) has resin layers 2b containing the nanofibers on both surfaces of the substrate 1 b. Fig. 1 (c) shows an example of the form of the substrate in the form (iii) in which the support 1c has resin layers 2c containing the nanofibers and the compound (a) on both surfaces.

Hereinafter, the layer containing at least one compound (a) and a resin is also referred to as a "transparent resin layer".

A minimum value (T) of transmittance in a region of 600nm to 1200nm in wavelength in the substrate ₁ ) Preferably 3% or less, more preferably 2% or less, and still more preferably 1% or less. If T ₁ In the above range, the transmittance cut-off of the absorption band is sufficient, and ghost (ghost) around the light source can be suppressed in the camera image, which is preferable.

In the above-mentioned substrate, the optimum range of the shortest wavelength (Xc) in which the transmittance is from more than 50% to 50% or less in the region of wavelength 550nm or more depends on the kind of application. For example, in the case of imaging applications, Xc is preferably 630nm to 655nm, more preferably 632nm to 652nm, and still more preferably 634nm to 650 nm. If Xc is less than 628nm, the transmittance in the wavelength region corresponding to red tends to be low, and color reproducibility tends to be low, and if Xc exceeds 658nm, sufficient absorption intensity cannot be secured, and color shading tends to occur in the camera image.

The haze value of the substrate is preferably 0.5% or less, more preferably 0.4% or less, and particularly preferably 0.35% or less. If the haze value is in the above range, flare around the light source can be suppressed in the camera image, which is preferable.

The linear expansion Coefficient (CTE) of the substrate in the range of 40 to 100 ℃ is preferably 60 ppm/DEG C or less, more preferably 50 ppm/DEG C or less, and particularly preferably 40 ppm/DEG C or less. When the CTE of the base material is in the above range, thermal deformation of the optical filter during formation of the dielectric multilayer film can be suppressed, and heat resistance can be improved, which is preferable.

The tensile modulus of elasticity of the substrate is preferably 3.0GPa or more, more preferably 3.5GPa or more, and particularly preferably 4.0GPa or more. When the tensile elastic modulus of the base material is in the above range, warpage of the optical filter in forming the dielectric multilayer film can be reduced, which is preferable.

The substrate in the above-mentioned form (ii) and the resin layer (coating film) formed on the support in the above-mentioned form (iii) preferably have a Martens hardness (Martens hardness) of 200N/mm ² More preferably 210N/mm as described above ² Above, 215N/mm is particularly preferable ² The above. When the hardness of the coating film is in the above range, the coating film is less likely to be scratched when an object comes into contact with the surface of the coating film, and therefore, the coating film is preferable.

In the case where the substrate is in the above-mentioned form (i), the following effects are exhibited.

1. By including the nanofibers, the substrate can be strengthened and CTE can be reduced, and warpage of the optical filter can be reduced. Therefore, the mechanical properties are improved and the substrate can be made thin.

2. By including the nanofibers, softening of the base material can be suppressed even in an environment where the glass transition temperature of the resin constituting the resin substrate is higher than or equal to the glass transition temperature, and the heat resistance as an optical filter can be improved.

3. By including the nanofibers, crack propagation during pressing of the optical filter can be suppressed, and the durability of the pressed end of the optical filter can be improved.

In the case where the substrate is in the form (ii), the following effects are exhibited.

1. When a coating film containing nanofibers is formed, the occurrence of sink defects which cause poor appearance can be suppressed.

2. The inclusion of the nanofibers improves the scratch resistance of the coating film surface, and prevents the adhesion of scratches which cause appearance defects.

3. By including the nanofibers, the substrate can be strengthened and CTE can be reduced, and warpage of the optical filter can be reduced. Therefore, the mechanical properties are improved and the film thickness of the substrate can be reduced.

4. When a resin substrate is used, the inclusion of nanofibers suppresses softening of the base material even in an environment where the glass transition temperature of the resin constituting the resin substrate is higher than or equal to the glass transition temperature of the resin, and improves heat resistance as an optical filter.

In the case where the substrate is in the above form (iii), the following effects are exhibited.

1. When a coating film containing the compound (a) is formed, the dispersion of the pigment is improved by containing the nanofibers in the coating liquid, and the Haze (Haze) of the coating film can be reduced.

2. When a coating film containing nanofibers is formed, the occurrence of a sink defect which causes a poor appearance can be suppressed.

3. The inclusion of the nanofibers improves the scratch resistance of the coating film surface, and prevents the adhesion of scratches which cause appearance defects.

4. By including the nanofibers, the substrate can be strengthened and CTE can be reduced, and warpage of the optical filter can be reduced. Therefore, the mechanical properties are improved and the substrate itself can be made thin.

5. When a resin support is used, the inclusion of nanofibers suppresses softening of the base material even in an environment where the glass transition temperature of the resin constituting the support is higher than or equal to the glass transition temperature, and improves heat resistance as an optical filter.

The thickness of the substrate is appropriately selected depending on the intended use, and is not particularly limited, but is preferably 20 to 120 μm, more preferably 30 to 110 μm, and particularly preferably 40 to 100 μm in the case of a resin-based substrate, and is preferably 70 to 250 μm, more preferably 90 to 200 μm, and particularly preferably 100 to 180 μm in the case of a glass-based substrate.

When the thickness of the base material is within the above range, the filter using the base material can be made thin and light in weight, and can be preferably used for various applications such as a solid-state imaging device. In particular, when the single-layered base material is used for a lens unit such as a camera module, the lens unit is preferably reduced in height and weight.

< optical filter >

The optical filter of the present invention (hereinafter also referred to as "present filter") contains the substrate of the present invention.

The filter may have a structure including only the substrate, and may further include a dielectric multilayer film or other functional film formed on at least one surface of the substrate as needed.

The average value of the transmittance of the filter measured from the direction perpendicular to the surface of the filter in the region of a wavelength of 430nm to 580nm is preferably 65% or more, more preferably 70% or more, still more preferably 75% or more, and particularly preferably 80% or more. When the average value of the transmittance in the wavelength region is within the above range, excellent imaging sensitivity can be achieved when the filter is used for a solid-state imaging device.

The average value of the transmittance of the filter measured from the direction perpendicular to the surface of the filter in the region of 900nm to 1050nm in wavelength is preferably 10% or less, more preferably 7% or less, still more preferably 6% or less, and particularly preferably 5% or less. If the average value of the transmittance in the wavelength region is in the above range, light which is invisible to human eyes and is unnecessary for sensing can be shielded when the filter is used for a solid-state imaging device.

In the filter, the absolute value | Xa-Xb | of the difference between the value (Xa) of the shortest wavelength at which the transmittance when measured from the vertical direction of the filter is 50% and the value (Xb) of the wavelength at which the transmittance when measured from an angle of 30 ° with respect to the vertical direction of the filter is 50% in the region of wavelengths 600nm to 800nm is preferably less than 20nm, more preferably 15nm or less, and still more preferably 10nm or less. When | Xa to Xb | fall within the above range, color shading can be suppressed when the filter is used for a solid-state imaging element.

The thickness of the filter may be appropriately selected depending on the intended use, and is preferably also thin in accordance with the recent trend toward thinner and lighter solid-state imaging devices and the like. The filter includes the substrate, and thus can be made thin.

When the substrate is a resin-based substrate, the thickness of the filter is preferably 150 μm or less, more preferably 100 μm or less, further preferably 70 μm or less, particularly preferably 40 μm or less, and the lower limit is not particularly limited, and the thickness is preferably small for thinning of the solid-state imaging device. When the substrate is a glass-based substrate, the thickness of the filter is preferably 270 μm or less, more preferably 230 μm or less, still more preferably 170 μm or less, and particularly preferably 140 μm or less.

< nanofiber >

The nanofibers are not particularly limited, and examples thereof include fibrous materials having a diameter (average fiber diameter) of 1nm to 100nm and a length (average fiber length) of 100 times or more the diameter. Examples of such fibrous materials include polymer nanofibers made of polypropylene, polyethylene terephthalate, or the like, cellulose nanofibers, Deoxyribonucleic Acid (DNA) nanofibers, carbon nanofibers, metal nanofibers, and the like, and among these, cellulose nanofibers are preferable, chemically modified cellulose nanofibers are more preferable, and hydrophobic cellulose nanofibers which can be dispersed in an organic solvent are particularly preferable.

Here, "cellulose nanofiber" refers to cellulose-containing nanofibers (cellulose nanofibers) or lignocellulose-containing nanofibers (lignocellulose nanofibers), and both are also collectively referred to as "cnf (cellulose nanofiber)". The "chemically modified cellulose nanofiber" refers to a chemically modified cellulose nanofiber or a chemically modified lignocellulose nanofiber, and is also collectively referred to as "chemically modified CNF". The phrase "dispersible in an organic solvent" means that the nanofibers do not aggregate or precipitate during the mixing with the organic solvent.

The cellulose nanofibers can be obtained by subjecting a raw material cellulose fiber to a defibration treatment. Examples of the raw material cellulose fiber include fibers separated from plant fibers such as pulp derived from plants, wood, cotton, hemp, bamboo, cotton, kenaf, hemp, jute, banana, coconut, and seaweed, fibers separated from animal fibers derived from sea squirts, which are marine animals, and bacterial cellulose derived from acetic acid bacteria. Among these, fibers separated from plant fibers, more preferably fibers obtained from plant fibers such as pulp and cotton, can be preferably used.

In the chemically modified CNF, for example, an alkanoyl group such as an acetyl group is introduced in place of a hydrogen atom of a hydroxyl group constituting a sugar chain of cellulose (that is, the hydroxyl group is chemically modified), whereby the hydroxyl group of a cellulose molecule is blocked, the hydrogen bonding force of the cellulose molecule is suppressed, and in addition, a crystal structure originally possessed by the cellulose fiber is retained at a specific ratio.

The modification method can be carried out according to a known method. For example, the cellulose fibers after the defibration treatment may be dispersed by adding to water or an appropriate solvent, and then a chemical modifier may be added thereto to react under appropriate reaction conditions. In the above-mentioned case, a reaction catalyst may be added as needed in addition to the chemical modifier, and for example, a basic catalyst such as pyridine, N-dimethylaminopyridine, triethylamine, sodium methoxide, sodium ethoxide, or sodium hydroxide, or an acidic catalyst such as acetic acid, sulfuric acid, or perchloric acid may be used. The reaction temperature is preferably about 40 to 100 ℃ from the viewpoint of suppressing deterioration such as yellowing of cellulose fibers or reduction in polymerization degree and ensuring the reaction rate. The reaction time may be appropriately selected depending on the modifier used and the treatment conditions.

As the chemically modified CNF, for example, there can be used: hydrophobized CNF in which a hydroxyl group present on the surface of a nanofiber is hydrophobized by modification with an acyl group, an alkyl group, or the like; modified CNF in which hydroxyl groups present on the surface of nanofibers are cationically modified by modification with a silane coupling agent having an amino group, glycidyl trialkyl ammonium halide, a halohydrin compound thereof, or the like; and modified CNF in which a hydroxyl group present on the surface of the nanofiber is modified with an anion by mono-esterification with a cyclic acid anhydride such as succinic anhydride or alkyl or alkenyl succinic anhydride, modification with a silane coupling agent having a carboxyl group, or the like.

Among these, CNF in which the hydroxyl group of the sugar chain constituting CNF is modified with an alkanoyl group (alkanoyl-modified CNF) is preferable in terms of ease of production, CNF modified with a lower alkanoyl group (lower alkanoyl-modified CNF) is more preferable, and CNF modified with an acetyl group (also referred to as Ac-CNF) is further preferable in terms of ease of production and production cost.

The acylation degree (degree of modification, ds (degree of acylation)) of the sugar chain hydroxyl group of the chemically modified CNF obtained by the acylation reaction is preferably about 0.05 to 2.5, more preferably about 0.1 to 1.7, and even more preferably about 0.15 to 1.5. The maximum value of the Degree of Substitution (DS) depends on the amount of sugar chain hydroxyl groups in CNF, and is about 2.7. By setting the Degree of Substitution (DS) to about 0.05 to 2.5, a chemically modified CNF having an appropriate crystallinity and Solubility Parameter (SP) value can be obtained. For example, in the acetylated CNF, the DS is preferably 0.29 to 2.52, and the crystallinity can be maintained at about 42.7% or more in the DS in the above range. The Degree of Substitution (DS) can be analyzed by various analytical methods such as elemental analysis, neutralization titration, Fourier Transform-Infrared Spectroscopy (FT-IR), and two-dimensional Nuclear Magnetic Resonance (NMR) (1H and 13C-NMR).

The average fiber diameter of the nanofibers is preferably 3nm to 200nm, more preferably 3nm to 150nm, and still more preferably 3nm to 100 nm. When the average fiber diameter is within the above range, light scattering by the nanofibers can be reduced, and when the nanofiber is applied to an optical filter, the transmittance can be improved and the Haze (Haze) can be reduced, and the strength and the CTE of the substrate can be increased and decreased.

The average fiber length of the nanofibers is preferably 0.2 to 10 μm, more preferably 0.3 to 5 μm, and still more preferably 0.4 to 3 μm. When the average fiber diameter is within the above range, light scattering by the nanofibers can be reduced, and when the nanofiber is applied to an optical filter, the transmittance can be improved and the Haze (Haze) can be reduced, and the strength and the CTE of the substrate can be increased and decreased.

In the present invention, the measurement of the "average fiber diameter" and the "average fiber length" can be performed by observing nanofibers at a magnification of 10000 times using a transmission electron microscope or a scanning electron microscope, randomly selecting 100 fibers from the obtained image, analyzing the fiber diameter and the fiber length of each fiber using image processing software, and calculating the diameter and the fiber length as a simple number average of the diameters and the fiber length.

The specific surface area of the nano-fiber is preferably 70m ² /g～300m ² A/g, more preferably 70m ² /g～250m ² (ii) g, more preferably 100m ² /g～200m ² (ii) in terms of/g. When the specific surface area is within the above range, the mechanical strength of the base material is improved, and the occurrence of warpage or cracking can be suppressed.

The crystallinity of the nanofibers is preferably 43% or more, more preferably 50% or more, further preferably 55% or more, and particularly preferably 60% to 80%. When the crystallinity is within the above range, the steel sheet exhibits high strength and low thermal expansion. The crystallinity refers to the presence ratio of crystals (mainly cellulose I-type crystals) in all cellulose in the case of cellulose nanofibers, for example.

When the structure of the base material is the form (i), the content of the nanofibers is preferably 5 to 50 parts by mass, more preferably 10 to 45 parts by mass, and still more preferably 10 to 40 parts by mass, based on 100 parts by mass of the total of the contents of the resin and the nanofibers constituting the resin substrate.

In the case where the structure of the substrate is in the form (ii) or (iii), the content of the nanofibers is preferably 5 to 70 parts by mass, more preferably 10 to 60 parts by mass, and still more preferably 10 to 50 parts by mass, based on 100 parts by mass of the total of the contents of the resin and the nanofibers constituting the resin layer.

When the content of the nanofibers is within the above range, the effects of the base material in the forms (i) to (iii) can be more clearly exhibited.

< Compound (A) >

The compound (a) is not particularly limited as long as it has an absorption maximum wavelength in a region having a wavelength of 600 to 1200nm, and is preferably a solvent-soluble dye compound, and more preferably a dye compound selected from the group consisting of polymethine-based compounds (e.g., squarylium-based compounds, cyanine-based compounds, etc.), pyrrolopyrrole-based compounds, crotonium-based compounds, diimmonium-based compounds, phthalocyanine-based compounds, naphthalocyanine-based compounds, tetraazaporphyrin-based compounds, porphyrin-based compounds, hexaphyrin-based compounds, metal dithiolate-based compounds, triarylmethane-based compounds, subphthalocyanine-based compounds, perylene-based compounds, squarylium-based compounds, styryl-based compounds, phenazine-based compounds, pyridomethylene-boron-based compounds, pyrazine-boron-based compounds, pyridone azo-based compounds, and the like, More preferably, the organic solvent is at least one selected from the group consisting of a xanthene compound and a Dipyrromethene compound, more preferably at least one selected from the group consisting of a squarylium compound, a phthalocyanine compound, a cyanine compound, a naphthalocyanine compound, a pyrrolopyrrole compound, a ketanium compound, a six-membered porphyrin compound, a metal dithiolate compound and a cyclo-extended Boron Dipyrromethene (BODIPY) compound, and still more preferably at least one selected from the group consisting of a squarylium compound, a cyanine compound, a ketanium compound and a pyrrolopyrrole compound.

The absorption maximum wavelength of the compound (A) is from 600nm to 1200nm, preferably from 630nm to 800nm, more preferably from 640nm to 780nm, and particularly preferably from 650nm to 760 nm. When the absorption maximum wavelength of the compound (a) is in such a range, light having a wavelength useful for near-infrared sensing can be transmitted, unnecessary near-infrared rays can be cut off, and the incident angle dependence of the near-infrared transmission band can be reduced.

When a base material including a resin substrate containing the compound (a) or a base material obtained by laminating a resin layer including a curable resin or the like on a resin substrate is used as the base material, the content of the compound (a) is preferably 0.01 to 2.0 parts by mass, more preferably 0.02 to 1.5 parts by mass, and particularly preferably 0.03 to 1.0 part by mass, based on 100 parts by mass of the resin forming the resin substrate containing the compound (a). When a substrate in which a transparent resin layer such as an overcoat layer containing a curable resin or the like containing the compound (a) is laminated on a glass substrate or a resin substrate is used as the substrate, the amount of the transparent resin layer containing the compound (a) is preferably 0.1 to 5.0 parts by mass, more preferably 0.2 to 4.0 parts by mass, and particularly preferably 0.3 to 3.0 parts by mass, based on 100 parts by mass of the resin forming the transparent resin layer. When the content of the compound (a) is within the above range, good near infrared absorption characteristics can be achieved.

When the base material is in a form using the near-infrared-absorbing glass substrate in the above-mentioned form (ii), the compound (a) is CuO. The absorption maximum wavelength of CuO is in the wavelength range of about 850nm to 900 nm.

As the near-infrared ray absorbing glass substrate, CuO-containing fluorophosphate glass or CuO-containing phosphate glass (hereinafter, these are collectively referred to as "CuO-containing glass") can be used. The use of CuO-containing glass provides high transmittance for visible light and high shielding properties for near infrared rays. In addition, a phosphate glass also contains SiO in a part of the glass skeleton ₂ The silicophosphate glass of (1).

Among the commercially available products, for example, there are: NF50-E, NF50-EX (manufactured by Asahi glass Co., Ltd.); BG-60, BG-61 (Schottky); BS-11 (manufactured by Songlanzi industries); CD5000 (manufactured by HOYA corporation), and the like.

The thickness of the CuO-containing fluorophosphate glass or CuO-containing phosphate glass is preferably in the range of 0.03mm to 5mm, and more preferably in the range of 0.05mm to 1mm from the viewpoints of strength, weight reduction, and low profile.

< resin >

The resin used for the (transparent) resin layer, the resin substrate, or the resin support constituting the substrate is not particularly limited as long as the effect of the present invention is not impaired, and for example, in order to ensure thermal stability and moldability into a film and to produce a film in which a dielectric multilayer film can be formed by high-temperature vapor deposition at a vapor deposition temperature of 100 ℃ or higher, a resin having a glass transition temperature (Tg) of preferably 110 to 380 ℃, more preferably 110 to 370 ℃, and still more preferably 120 to 360 ℃ may be cited. Further, when the glass transition temperature of the resin is 150 ℃ or higher, a film having a glass transition temperature, which enables formation of a dielectric multilayer film by high-temperature vapor deposition, can be obtained even when a compound is added to the resin at a high concentration and the glass transition temperature is lowered, and therefore, such a resin is particularly preferable.

As the resin, a resin having a total light transmittance (Japanese Industrial Standards, JIS) K7105) of preferably 75% to 95%, more preferably 78% to 95%, and particularly preferably 80% to 95% when a resin sheet having a thickness of 0.05mm containing the resin is formed can be used. When a resin having such a total light transmittance is used, the obtained substrate exhibits good transparency as an optical film.

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

Examples of the resin include: a cyclic polyolefin-based resin, an aromatic polyether-based resin, a polyimide-based resin, a fluorene polycarbonate-based resin, a fluorene polyester-based resin, a polycarbonate-based resin, a polyamide-based resin, an aromatic polyamide-based resin, a polysulfone-based resin, a polyether sulfone-based resin, a polyphenylene-based resin, a polyamideimide-based resin, a polyethylene naphthalate-based resin, a fluorinated aromatic polymer-based resin, a (modified) acrylic-based resin, an epoxy-based resin, a silsesquioxane-based ultraviolet curable resin, a maleimide-based resin, an alicyclic epoxy thermosetting resin, a polyether ether ketone-based resin, a polyarylate-based resin, an allyl-based curable resin, an acrylic-based ultraviolet curable resin, a vinyl-based ultraviolet curable resin, and a resin containing silica as a main component formed by a sol-gel method. Among these, in order to obtain an optical filter having an excellent balance among transparency (optical characteristics), heat resistance, reflow resistance, and the like, it is preferable to use a cyclic polyolefin resin, an aromatic polyether resin, a fluorene polycarbonate resin, a fluorene polyester resin, a polycarbonate resin, and a polyarylate resin.

(commercially available products)

As a commercially available product of the transparent resin, the following commercially available products can be mentioned. Examples of commercially available products of the cyclic polyolefin resin include: anton (Arton) manufactured by JSR (stock), renooa (Zeonor) manufactured by nippon (stock), Apiel (APEL) manufactured by mitsui chemical (stock), TOPAS (TOPAS) manufactured by polyplasics (stock), and the like. Commercially available products of polyethersulfone resin include smikaikecel (Sumikaexcel) PES manufactured by sumitomo chemical (stock). Examples of commercially available polyimide resins include Nippopim (Neopulim) L manufactured by Mitsubishi gas chemistry (Strand). As a commercially available product of the polycarbonate-based resin, there can be mentioned Pures (PURE-ACE) manufactured by Dichen (R). As a commercial product of the fluorene polycarbonate-based resin, there can be mentioned Eupatorium (Iipizeta) EP-5000 manufactured by Mitsubishi gas chemistry (Strand). Examples of commercially available fluorene polyester resins include OKP4HT manufactured by Osaka Gas Chemicals (Osaka Gas Chemicals). Examples of commercially available acrylic resins include akylivera (Acryviewa) manufactured by japan catalyst (japan). Examples of commercially available products of silsesquioxane-based ultraviolet curable resins include hillaplace (Silplus) manufactured by sienna chemical corporation.

< other ingredients >

The base material may further contain additives such as an antioxidant, a near-ultraviolet absorber, and a fluorescent matting agent, within a range not impairing the effects of the present invention. These other components may be used alone or in combination of two or more.

Near ultraviolet absorbent

The near-ultraviolet absorber is not particularly limited as long as it has at least one absorption maximum wavelength in a region of a wavelength of 250nm to 420nm, and examples thereof include: azomethine compounds, indole compounds, benzotriazole compounds, triazine compounds, anthracene compounds, and the like.

Antioxidant(s)

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

The additive may be mixed with a resin or the like at the time of producing the transparent resin, or may be added at the time of synthesizing the resin. The amount to be added may be appropriately selected depending on the desired properties, and is usually 0.01 to 5.0 parts by mass, preferably 0.05 to 2.0 parts by mass, based on 100 parts by mass of the transparent resin.

< support body >

Support made of resin

The resin used for the resin substrate or the resin support is as described above.

Support made of glass

The glass support is not particularly limited, and examples thereof include: borosilicate glass, silicate glass, soda-lime glass, near-infrared absorbing glass, and the like.

< method for producing substrate >

When the base material is a base material including the resin substrate in the above-described forms (i) and (ii), the resin substrate may be formed by, for example, melt molding or cast molding, and further, if necessary, a coating agent such as an antireflective agent, a hard coating agent, and/or an antistatic agent may be applied after the molding.

When the substrate is the substrate of the above-mentioned form (iii), for example, a transparent resin layer containing the compound (a) and the nanofibers can be formed on a glass support or a resin support by melt-molding or cast-molding a resin solution containing the compound (a) and the nanofibers, preferably by applying the resin solution by a method such as spin coating, slit coating, or ink jet, then drying the solvent to remove it, and further irradiating or heating the substrate with light or heat as necessary.

Melt forming

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

Casting and Forming

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

In the case where the substrate is a substrate comprising a resin substrate containing the compound (a), the substrate can be obtained by peeling off the coating film from a support after casting molding, and in the case where the substrate is a substrate in which a transparent resin layer such as an overcoat layer containing the compound (a) and comprising a curable resin or the like is laminated on a support such as a glass support or a resin support, the substrate can be obtained by not peeling off the coating film after casting molding.

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

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

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

In the case of the above-mentioned form (i), the web strength of the base material at the time of casting is improved, and therefore the following effects are exhibited:

(1) can be peeled off from the support body in the early stage of drying,

(2) in the production of the substrate, for example, the substrate is not broken halfway when being transported by being sandwiched by rollers or a tenter,

(3) the drying temperature can be increased to such an extent that the resin does not soften or yellow during drying,

thus, productivity is improved.

Further, since the base material can be made thinner, the drying rate is increased, and as a result, the following effects are obtained:

(4) the productivity can be improved by shortening the drying time,

(5) deterioration of the resin and the coloring matter due to heating can be suppressed.

In the case where the base material is in the form (ii), when the resin layer containing nanofibers is formed on the substrate by coating, coating defects can be reduced by the physical properties of the coating liquid such as:

(1) the coating liquid flows in the shearing part of the coating head,

(2) after coating, dishing can be suppressed by thickening or gelation caused by standing.

In the case where the base material is in the form (iii), when a resin layer containing nanofibers and a pigment is formed by coating on a substrate, coating defects can be reduced by the physical properties of the coating liquid such as:

(1) the coating liquid flows in the shearing part of the coating head,

In addition, even if the drying temperature is increased after thickening or gelling after coating, the uneven distribution of the coloring matter (pigment) can be suppressed, and therefore, the drying efficiency of the resin layer can be improved.

< dielectric multilayer film >

The filter may have a dielectric multilayer film as necessary. The dielectric multilayer film may be a laminate in which high refractive index material layers and low refractive index material layers are alternately laminated.

The dielectric multilayer film may be provided on one side or both sides of the substrate. When the optical filter is arranged on one surface, the manufacturing cost and the manufacturing easiness are excellent, and when the optical filter is arranged on two surfaces, the optical filter which has high strength and is not easy to warp or twist can be obtained. When the filter is used for a solid-state imaging device or the like, the filter is preferably small in warpage or distortion, and therefore, the dielectric multilayer film is preferably provided on both surfaces of the base material.

The material constituting the high refractive index material layer includes a material having a refractive index of 1.7 or more, and a material having a refractive index of usually 1.7 to 2.5 is selected. Examples of such materials include: a material containing titanium oxide, zirconium oxide, tantalum pentoxide, niobium pentoxide, lanthanum oxide, yttrium oxide, zinc sulfide, indium oxide, or the like as a main component and a small amount (for example, 0 to 10 mass% with respect to the main component) of tin oxide and/or cerium oxide, or the like.

As the material constituting the low refractive index material layer, a material having a refractive index of 1.6 or less can be used, and a material having a refractive index of usually 1.2 to 1.6 is selected. Examples of such materials include: silicon dioxide, aluminum oxide, lanthanum fluoride, magnesium fluoride and sodium aluminum hexafluoride.

The method of laminating the high refractive index material layer and the low refractive index material layer is not particularly limited as long as a dielectric multilayer film in which these material layers are laminated is formed. For example, a dielectric multilayer film in which high refractive index material layers and low refractive index material layers are alternately stacked may be directly formed on a substrate by a Chemical Vapor Deposition (CVD) method, a sputtering method, a vacuum evaporation method, an ion-assisted evaporation method, an ion plating method, or the like.

In general, when the wavelength of the near infrared ray to be blocked is λ (nm), the thickness of each of the high refractive index material layer and the low refractive index material layer is preferably 0.1 λ to 0.5 λ. The value of λ (nm) is, for example, 700nm to 1400nm, preferably 750nm to 1300nm in the case of a Near Infrared Ray Color Filter (NIR-CF). When the thickness of each of the high refractive index material layer and the low refractive index material layer is within the above range, the optical film thickness, which is the product (n × d) of the refractive index (n) and the film thickness (d), has a value substantially equal to λ/4, and the blocking and transmission of a specific wavelength tends to be easily controlled in accordance with the relationship between the optical characteristics of reflection and refraction.

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

In the present filter, the types of materials constituting the high refractive index material layer and the low refractive index material layer, the thicknesses of the respective layers of the high refractive index material layer and the low refractive index material layer, the order of lamination, and the number of lamination are appropriately selected in accordance with the absorption characteristics of the compound (a) and the like, whereby a sufficient transmittance is ensured in a wavelength region to be transmitted (for example, visible region), a sufficient light cut-off characteristic is provided in a near infrared wavelength region to be cut off, and the reflectance when near infrared rays are incident from an oblique direction can be reduced.

In order to optimize the condition of the dielectric multilayer Film, for example, optical Thin Film design software (e.g., manufactured by core metal machine, Thin Film Center) may be used to set parameters so as to achieve both the antireflection effect in a wavelength region (e.g., visible region) to be transmitted and the light-blocking effect in a near-infrared region to be blocked. In the case of the software, for example, in the case of forming a dielectric multilayer film of NIR — CF, a parameter setting method is used, such as setting the Target transmittance at a wavelength of 400nm to 700nm to 100%, setting the value of the Target Tolerance (Target Tolerance) to 1, setting the Target transmittance at a wavelength of 705nm to 950nm to 0%, and setting the value of the Target Tolerance to 0.5.

These parameters may also be used to vary the value of the Target Tolerance (Target Tolerance) by more finely dividing the wavelength range in conjunction with various characteristics of the substrate, and the like.

< other functional membranes >

In the filter of the present invention, a functional film such as an antireflection film, a hard coat film or an antistatic film may be appropriately provided between the substrate and the dielectric multilayer film, on the surface opposite to the surface of the substrate on which the dielectric multilayer film is provided, or on the surface opposite to the surface of the dielectric multilayer film on which the substrate is provided, for the purpose of improving the surface hardness of the substrate or the dielectric multilayer film, improving chemical resistance, antistatic property, and eliminating damage, within a range not impairing the effects of the present invention.

The filter may include one layer of the functional film or two or more layers. When the filter includes two or more layers of the functional film, the filter may include two or more layers of the same film or two or more layers of different films.

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

The dielectric multilayer film can also be produced by applying a curable composition containing the above-mentioned coating agent or the like to a substrate or a dielectric multilayer film using a bar coater or the like, and then curing the composition by ultraviolet irradiation or the like.

Examples of the coating agent include Ultraviolet (UV)/Electron Beam (EB) curable resins and thermosetting resins, and specifically include: vinyl compounds, urethane, acrylic ester, epoxy and epoxy acrylate resins, and the like. One coating agent may be used alone, or two or more coating agents may be used.

The curable composition containing these coating agents includes: and vinyl, urethane, acrylic ester, epoxy, and epoxy acrylate curable compositions.

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

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

Further, an organic solvent may be added to the curable composition as a solvent, and a known solvent may be used as the organic solvent. Specific examples of the organic solvent include: alcohols such as methanol, ethanol, isopropanol, butanol, and octanol; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; esters such as ethyl acetate, butyl acetate, ethyl lactate, γ -butyrolactone, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, and the like; ethers such as ethylene glycol monomethyl ether and diethylene glycol monobutyl ether; aromatic hydrocarbons such as benzene, toluene, and xylene; amides such as dimethylformamide, dimethylacetamide and N-methylpyrrolidone.

These solvents may be used alone or in combination of two or more.

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

In addition, for the purpose of improving the adhesion between the substrate and the functional film and/or the dielectric multilayer film or between the functional film and the dielectric multilayer film, the surface of the substrate, the functional film, or the dielectric multilayer film may be subjected to surface treatment such as corona treatment or plasma treatment.

< use of optical Filter >

The present filter is excellent in, for example, the cutoff capability of light having a wavelength in a region to be cut off and the transmission capability of light having a wavelength to be transmitted. Therefore, the present invention is useful for visibility correction of a solid-state image sensor such as a CCD or CMOS image sensor as a camera module. In particular, the present invention is useful in digital still cameras, cameras for smartphones, cameras for mobile phones, digital video cameras, cameras for wearable devices, Personal Computer (PC) cameras, monitoring cameras, cameras for automobiles, infrared cameras, televisions, car navigation systems, portable information terminals, video game machines, portable game machines, fingerprint authentication systems, digital music players, various sensing systems, infrared communication, and the like. Further, the present invention is also useful as an infrared cut filter or the like mounted on a glass plate or the like of an automobile, a building or the like.

Solid-state imaging device

The solid-state imaging device of the present invention includes the present filter. Here, the solid-state imaging device is a device including a solid-state imaging element such as a CCD or CMOS image sensor, and is specifically used for applications such as a digital still camera, a camera for a smartphone, a camera for a mobile phone, a camera for a wearable device, and a digital video camera.

Camera module

The camera module of the invention comprises the optical filter of the invention. Here, the camera module includes an image sensor, a focus adjustment mechanism, a phase detection mechanism, a distance measurement mechanism, and the like, and outputs image or distance information as an electric signal.

[ examples ]

The present invention will be described more specifically with reference to the following examples, but the present invention is not limited to these examples at all.

< molecular weight >

The molecular weight of the resin is measured by the following method (a) or (b) in consideration of the solubility of each resin in a solvent and the like.

(a) The weight-average molecular weight (Mw) and the number-average molecular weight (Mn) in terms of standard polystyrene were measured using a Gel Permeation Chromatography (GPC) apparatus (150C type, H type column manufactured by Tosoh, Strand) and a developing solvent (o-dichlorobenzene).

(b) The weight average molecular weight (Mw) and the number average molecular weight (Mn) in terms of standard polystyrene were measured using a GPC apparatus (HLC-8220 type, column: TSKgel. alpha. -M, developing solvent: Tetrahydrofuran (THF)) manufactured by Tosoh (Tosoh).

Further, with respect to the resin synthesized in resin synthesis example 3 described later, the logarithmic viscosity was measured by the following method (c) without measuring the molecular weight by the above-mentioned method.

(c) A part of the polyimide solution was put into anhydrous methanol to precipitate polyimide, which was separated from the unreacted monomers by filtration, and then vacuum-dried at 80 ℃ for 12 hours. 0.1g of the obtained polyimide was dissolved in 20mL of N-methyl-2-pyrrolidone (diluted polyimide solution), and the logarithmic viscosity (. mu.) at 30 ℃ was determined from the following formula using Cannon-Fenske viscometer.

μ＝{ln(ts/t0)}/C

t 0: flowing-down time of solvent (N-methyl-2-pyrrolidone)

ts: flow down time of thin polyimide solution

C：0.5g/dL

< glass transition temperature (Tg) >

The glass transition temperature of the resin was measured using a differential scanning calorimeter (DSC6200) manufactured by Hitachi High-Tech Science (stock), and the glass transition temperature was measured at a temperature increase rate: the measurement was carried out at 20 ℃ per minute under a nitrogen stream.

< spectral transmittance >

The transmittance in each wavelength region of the substrate and the optical filter was measured by using a spectrophotometer (U-4100) manufactured by Hitachi High-Technologies, Inc. The transmittance is measured by using the spectrophotometer under the condition that light is vertically incident on the substrate or the optical filter.

< Haze (Haze) (%) >)

For the substrate of the form (iii), a Haze value (%) was measured using a Haze meter ("Haze-guard II" manufactured by BYK Gardner (BYK-Gardner)).

< coefficient of linear expansion: CTE (ppm/. degree. C.) >)

The temperature of the substrate was varied in the range of 40 ℃ to 160 ℃ and the linear expansion coefficient (unit: ppm/. degree. C.) was measured in the range of 40 ℃ to 100 ℃. As the measuring apparatus, "EXSTAR 6000TMA/SS 6100" manufactured by Seiko instruments (SII) was used.

< tensile elastic modulus (GPa) >

The tensile modulus was calculated by performing a tensile test at 5mm/min using a JIS K6251-3 dumbbell press base. As the measuring apparatus, a small bench test machine ("EZ-LX" manufactured by Shimadzu corporation) was used.

< Ma hardness (N/mm) ² )＞

The mahalanobis hardness was measured from the load (mN) when the substrate in the form (ii) or (iii) was pressed from the surface to a depth of 0.3 μm with a vickers indenter using a fine hardness measuring instrument ("picometer) HM 500" manufactured by fisher Instruments.

< scratch resistance >

The substrate in the forms (II) and (iii) was visually checked for the loading of gauze (BeMCOT) M-3II) at 100g/cm based on the following criteria ² The state of occurrence of scratches on the coating film (resin layer) after 10 round trips.

Good: no scratch

And (delta): with minor scratches (level to be tolerated)

X: with scratches (intolerable level)

< method for confirming dishing defect of coating surface >

A coating film (resin layer) was formed on one surface of a substrate, and then light of a desk lamp (fluorescent lamp) was irradiated to an area of 50mm × 50mm of the coating film (resin layer) formed surface in a dark room and the number of depressions was visually counted.

< Heat distortion of optical Filter >

An optical filter of 25mm × 30mm was cut from a sheet obtained by forming a dielectric multilayer film on both sides of a substrate, and the sheet was left to stand on a hot plate heated to 180 ℃ so that the filter surface was in contact with the hot plate, and heated for 5 minutes. After heating, the filter was cooled, and the appearance of the filter surface was determined according to the following criteria.

Good: no change in appearance of the surface

X: the appearance of the surface changes (bubbles or orange peel-like fog is generated)

< warping of optical Filter >

An optical filter of 6mm × 8mm was cut from a sheet obtained by forming a dielectric multilayer film on both sides of a substrate, the height of the optical filter at 9 in the plane was measured, and an approximate plane passing through 9 was calculated by the least square method. The distance between each measurement point and the approximate plane is calculated, and the distance between 2 points farthest from the plane is determined as the warp according to the following criteria.

Excellent: warpage ≦ 30 μm

O: 30 μm < warpage ≦ 50 μm (acceptable level)

X: 50 μm < warpage (unacceptable level)

< impact resistance of optical Filter >

The optical filter was incorporated into the camera module, the camera module was dropped from a position of height 2m, and the state of the optical filter was visually confirmed according to the following criteria.

Good: optical filter invariant

X: frequent cracking (unacceptable level for use as a high-quality camera module)

< Chip On Board (COB) manufacturability >

An optical filter chip of 6mm × 8mm was cut from a sheet obtained by forming a dielectric multilayer film on both sides of a substrate. An adhesive is applied to the end of the chip and the chip is bonded to a resin board to produce a COB. Based on the state of the COB, visual confirmation was performed according to the following criteria.

Good: chip without poor adhesion

X: chip with poor adhesion

< color shade evaluation of camera image >

An optical filter is incorporated into a camera module in the same manner as in japanese patent laid-open No. 2016-110067, a white plate of 300mm × 400mm size is photographed under a D65 light source ("Macbeth Judge II") which is a standard light source device manufactured by alice (X-Rite), and the difference in color tones between the central portion and the end portion of the white plate in a camera image is evaluated by the following criteria.

Good component: has no problem at all

X: with a significant difference in hue (level not tolerable for normal camera module use)

[ resin Synthesis example 1]

The following 8-methyl-8-methoxycarbonyltetracyclo [4.4.0.1 ] is introduced ^2,5 .1 ^7,10 ]100 parts by mass of dodec-3-ene (hereinafter also referred to as "DNM"), 18 parts by mass of 1-hexene (molecular weight modifier) and 300 parts by mass of toluene (solvent for ring-opening polymerization) were charged in a reaction vessel purged with nitrogen, and the solution was heated to 80 ℃. Then, 0.2 part by mass of a toluene solution of triethylaluminum (0.6 mol/liter) and 0.9 part by mass of a toluene solution of methanol-modified tungsten hexachloride (concentration: 0.025 mol/liter) were added to the solution in the reaction vessel as polymerization catalysts, and the solution was heated and stirred at 80 ℃ for 3 hours to perform a ring-opening polymerization reaction, thereby obtaining a ring-opening polymer solution. The polymerization conversion in the polymerization reaction was 97%.

[ solution 1]

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

[ resin Synthesis example 2]

To a 3L four-necked flask were added 35.12g (0.253mol) of 2, 6-difluorobenzonitrile, 87.60g (0.250mol) of 9, 9-bis (4-hydroxyphenyl) fluorene, 41.46g (0.300mol) of potassium carbonate, 443g of N, N-dimethylacetamide and 111g of toluene. Then, a thermometer, a stirrer, a three-way cock with a nitrogen inlet, a Dean-Stark tube, and a cooling tube were placed in the four-necked flask. Then, after the flask was purged with nitrogen, the obtained solution was reacted at 140 ℃ for 3 hours, and water produced was removed from the dean stark tube as needed. When no water was produced, the temperature was gradually increased to 160 ℃ and the reaction was carried out at the temperature for 6 hours. After that, the reaction mixture was cooled to room temperature (25 ℃), the formed salt was removed by filter paper, and the filtrate was put into methanol to reprecipitate, and the filtrate (residue) was separated by filtration. The obtained filtrate was vacuum-dried at 60 ℃ overnight, whereby a white powder of an aromatic polyether resin (hereinafter also referred to as "resin B") was obtained (yield 95%). The obtained resin B had a number average molecular weight (Mn) of 75,000, a weight average molecular weight (Mw) of 188,000 and a glass transition temperature (Tg) of 285 ℃.

[ resin Synthesis example 3]

27.66g (0.08 mol) of 1, 4-bis (4-amino-. alpha.,. alpha. -dimethylbenzyl) benzene and 7.38g (0.02 mol) of 4,4' -bis (4-aminophenoxy) biphenyl were placed in a 500mL five-necked flask equipped with a thermometer, a stirrer, a nitrogen introduction tube, a side-capped dropping funnel, a dean Stark tube and a cooling tube under a nitrogen stream, and dissolved in 68.65g of γ -butyrolactone and 17.16g of N, N-dimethylacetamide. The obtained solution was cooled to 5 ℃ using an ice water bath, kept isothermal, and 22.62g (0.1 mol) of 1,2,4, 5-cyclohexanetetracarboxylic dianhydride and 0.50g (0.005 mol) of triethylamine as an imidization catalyst were added at once. After the addition was completed, the temperature was raised to 180 ℃ and the distillate was distilled off at any time and refluxed for 6 hours. After the reaction was completed, the reaction mixture was cooled with air until the internal temperature reached 100 ℃, and then 143.6g of N, N-dimethylacetamide was added thereto to dilute the mixture, followed by stirring and cooling, thereby obtaining 264.16g of a polyimide solution having a solid content concentration of 20 mass%. A portion of the polyimide solution was poured into 1L of methanol to precipitate polyimide. The polyimide separated by filtration was washed with methanol and dried in a vacuum dryer at 100 ℃ for 24 hours, whereby a white powder of a polyimide resin (hereinafter also referred to as "resin C") was obtained. The Infrared (IR) spectrum of the obtained resin C was measured, and it was found that 1704cm was peculiar to the imide group ^-1 、1770cm ^-1 Absorption of (2). Glass of resin CThe transition temperature (Tg) was 310 ℃ and the logarithmic viscosity was measured to be 0.87.

[ Synthesis examples of hydrophobic CNF ]

Sulfurous acid bleached pulp (cellulose fibers) obtained from conifers was added to Pure water so as to be 0.1 mass%, and the cellulose fibers were defibrated by performing a grinding process (rotation speed: 1500 rpm) 70 times using a stone mortar type pulverizer (Pure Fine Mill) KMG 1-10; manufactured by shiitake machinery manufacturing company). The aqueous dispersion was filtered, washed with pure water, and dried at 70 ℃. After cellulose nanofibers a in an amount of 1g, 0.0125g of 2,2,6,6-Tetramethylpiperidine-N-oxyl (2,2,6,6-Tetramethylpiperidine-N-oxyl, TEMPO) and 0.125g of sodium bromide were dispersed in 100ml of water by dry mass, 13 mass% sodium hypochlorite aqueous solution was added so that the amount of sodium hypochlorite became 2.5mmol, and the reaction was started. During the reaction, 0.5M aqueous sodium hydroxide solution was added dropwise to maintain the pH at 10.5. The reaction was terminated at the point where no change in pH was observed. After the reaction product was filtered by a glass filter, washing with water and filtration were repeated 5 times using a sufficient amount of water, and further, treatment was performed for 1 hour by an ultrasonic disperser. The resulting mixture was dried at 70 ℃ to obtain cellulose nanofibers B. Further, to 500 parts by mass of a propionic anhydride/pyridine (molar ratio 1/1) solution, cellulose nanofiber B10 parts by mass was added and dispersed, and the mixture was stirred at room temperature for 4 hours. Next, the cellulose nanofibers after dispersion were filtered, washed 5 times with 500 parts by mass of water, and then washed 2 times with 200 parts by mass of ethanol. Drying at 70 ℃ gave hydrophobic CNF. The obtained hydrophobic CNF had an average fiber diameter of 4nm and an average fiber length of 1 μm as observed by a scanning electron microscope. Further, the specific surface area obtained by the Brunauer-Emmett-Teller (BET) method was 270m ² (ii) in terms of/g. The crystallinity obtained according to the X-ray diffraction method was 79%.

Example A1

[ production of base Material ]

To a vessel, 90 parts by mass of the resin a obtained in resin synthesis example 1, 0.04 part by mass of the following compound (a1) (absorption maximum wavelength in dichloromethane is 704nm) as the compound (a), 0.08 part by mass of the following compound (a2) (absorption maximum wavelength in dichloromethane is 738nm), 10 parts by mass of the hydrophobic CNF obtained in hydrophobic CNF synthesis example as nanofibers, and Tetrahydrofuran (THF) were added to prepare a solution having a resin concentration of 20% by mass. The solution obtained was cast onto a smooth glass plate and, after drying at 20 ℃ for 8 hours, peeled off from the glass plate. The peeled coating film was dried at 100 ℃ for 8 hours under reduced pressure to obtain a base material (A1) comprising a resin substrate having a thickness of 0.1mm, a vertical length of 210mm and a horizontal length of 210 mm. The mechanical properties and optical properties of the obtained substrate (a1) were evaluated. The results are shown in table 3.

[ solution 2]

[ solution 3]

[ production of optical Filter ]

A dielectric multilayer film (I) was formed on one surface of the obtained substrate (A1), and a dielectric multilayer film (II) was formed on the other surface of the substrate, to obtain an optical filter having a thickness of about 0.110 mm. The optical characteristics and properties of the obtained optical filter were evaluated. The results are shown in table 3.

The dielectric multilayer film (I) is prepared by depositing silicon dioxide (SiO) at a deposition temperature of 100 deg.C ₂ ) Layer with titanium dioxide (TiO) ₂ ) A laminate (26 layers in total) in which the layers are alternately laminated. The dielectric multilayer film (II) is formed by depositing silicon dioxide (SiO) at a deposition temperature of 100 deg.C ₂ ) Layer with titanium dioxide (TiO) ₂ ) A laminate (20 layers in total) in which the layers are alternately laminated.

In any of the dielectric multilayer film (I) and the dielectric multilayer film (II), a silica layer and a titania layer are alternately laminated in this order from the substrate side to form a titania layer, a silica layer, a titania layer, … a silica layer, a titania layer, and a silica layer, and the outermost layer of the optical filter is defined as a silica layer.

The thickness and number of layers of each layer are optimized by using optical Film design software (manufactured by core mclaud (Essential mechanical) and Thin Film Center (Thin Film Center)) in combination with the wavelength dependence of the refractive index of the substrate and the absorption of the compound (a) used so that good transmittance in the visible region and reflection performance in the near infrared region can be achieved. In the present embodiment, the input parameters (Target values) for the software are set as shown in table 1 below when the optimization is performed.

[ Table 1]

TABLE 1

As a result of optimizing the film structure, the dielectric multilayer film (I) is a multilayer deposited film having 26 layers stacked alternately by stacking a silicon dioxide layer having a film thickness of about 31 to 157nm and a titanium dioxide layer having a film thickness of about 10 to 95nm, and the dielectric multilayer film (II) is a multilayer deposited film having 20 layers stacked alternately by stacking a silicon dioxide layer having a film thickness of 37 to 194nm and a titanium dioxide layer having a film thickness of about 12 to 114 nm. An example of the optimized film structure is shown in table 2 below.

[ Table 2]

TABLE 2

*λ＝550nm

Example A2

[ production of base Material ]

A solution having a resin concentration of 8 mass% was prepared in the same manner as in example a1, except that the amount of the resin a was changed to 80 parts by mass, the amount of the compound (a1) was changed to 0.10 parts by mass, the amount of the compound (a2) was changed to 0.20 parts by mass, and the amount of the hydrophobic CNF was changed to 20 parts by mass. Using the obtained solution, a base material (a2) including a resin substrate having a thickness of 0.04mm after drying was obtained in the same manner as in example a 1. The mechanical properties and optical properties of the obtained base material (a2) were evaluated. The results are shown in table 3.

[ production of optical Filter ]

In the same manner as in example a1 except that the obtained base material (a2) was used, a dielectric multilayer film (I) was formed on one surface of the base material (a2) and a dielectric multilayer film (II) was formed on the other surface thereof, to obtain an optical filter having a thickness of about 0.050 mm. The optical characteristics and properties of the obtained optical filter were evaluated. The results are shown in table 3.

Example A3

[ production of base Material ]

A solution having a resin concentration of 16 mass% was prepared in the same manner as in example a1, except that the resin B was used in an amount of 90 parts by mass in place of the resin a, and 0.075 part by mass of the compound (a2) and 0.075 part by mass of the following compound (A3) were used as the compound (a). Using the obtained solution, a resin substrate having a thickness of 0.08mm after drying was obtained in the same manner as in example A1.

[ solution 4]

On one side of the obtained resin substrate, a resin composition (1) having the following composition was applied by a bar coater, and heated at 70 ℃ for 2 minutes in an oven to evaporate and remove the solvent. At this time, the coating conditions of the bar coater were adjusted so that the thickness after drying became 5 μm. Next, exposure was carried out using a conveyer type exposure machine (exposure amount 500 mJ/cm) ² 200mW) of the resin composition (1) was cured to form a resin layer on the resin substrate. Similarly, a resin layer containing the resin composition (1) was formed on the other surface of the resin substrate, and a substrate (a3) having resin layers on both surfaces of the resin substrate was obtained.The mechanical properties and optical properties of the obtained substrate (a3) were evaluated. The results are shown in table 3.

Resin composition (1): 60 parts by mass of tricyclodecane dimethanol diacrylate, 40 parts by mass of dipentaerythritol hexaacrylate, 5 parts by mass of 1-hydroxycyclohexyl phenyl ketone, and 30% of Isopropyl Alcohol (IPA) (solvent, Solid Concentration (TSC))

[ production of optical Filter ]

In the same manner as in example a1 except that the obtained base material (A3) was used, the dielectric multilayer film (I) was formed on one surface of the base material (A3) and the dielectric multilayer film (II) was formed on the other surface, whereby an optical filter having a thickness of about 0.100mm was obtained. The optical characteristics and properties of the obtained optical filter were evaluated. The results are shown in table 3.

Example A4

[ production of base Material ]

A solution having a resin concentration of 10 mass% was prepared in the same manner as in example A3 except that the amount of the resin B was changed to 70 parts by mass, the amount of the compound (a2) was changed to 0.12 part by mass, the amount of the compound (A3) was changed to 0.12 part by mass, and the amount of the hydrophobic CNF was changed to 30 parts by mass. Using the obtained solution, a resin substrate having a thickness of 0.05mm after drying was obtained in the same manner as in example A3.

On one side of the obtained resin substrate, a resin composition (2) having the following composition was applied by a bar coater, and heated at 70 ℃ for 2 minutes in an oven to evaporate and remove the solvent. At this time, the coating conditions of the bar coater were adjusted so that the thickness after drying became 5 μm. Next, exposure was carried out using a conveyer type exposure machine (exposure amount 500 mJ/cm) ² 200mW) of the resin composition (2) was cured to form a resin layer on the resin substrate. Similarly, a resin layer containing the resin composition (2) was formed on the other surface of the resin substrate, and a substrate (a4) having resin layers on both surfaces of the resin substrate was obtained. The mechanical properties and optical properties of the obtained substrate (a4) were evaluated. The results are shown in table 3.

Resin composition (2): 100 parts by mass of tricyclodecane dimethanol diacrylate, 5 parts by mass of 1-hydroxycyclohexyl phenyl Ketone, and Methyl Ethyl Ketone (MEK) (concentration of solvent and solid content (TSC): 30%)

[ production of optical Filter ]

In the same manner as in example a1 except that the obtained substrate (a4) was used, a dielectric multilayer film (I) was formed on one surface of the substrate (a4) and a dielectric multilayer film (II) was formed on the other surface, whereby an optical filter having a thickness of about 0.070mm was obtained. The optical characteristics and properties of the obtained optical filter were evaluated. The results are shown in table 3.

Example A5

[ production of base Material ]

A solution having a resin concentration of 8 mass% was prepared in the same manner as in example a1, except that the resin C was used in an amount of 90 parts by mass in place of the resin a, 0.10 parts by mass of the following compound (a4) and 0.10 parts by mass of the following compound (a5) were used as the compound (a), and methyl ethyl ketone was used in place of tetrahydrofuran as a solvent for dissolving the resin. Using the obtained solution, a resin substrate having a thickness of 0.04mm after drying was obtained in the same manner as in example A1.

[ solution 5]

[ solution 6]

The resin composition (1) was applied to one surface of the obtained resin substrate by a bar coater, and the substrate was heated at 70 ℃ for 2 minutes in an oven to evaporate the solvent. At this time, the coating conditions of the bar coater were adjusted so that the thickness after drying became 5 μm. Next, exposure was carried out using a conveyer type exposure machine (exposure amount 500 mJ/cm) ² 200mW) of the resin composition (1) was cured to form a resin layer on the resin substrate. Also, the same applies toThen, a resin layer containing the resin composition (1) was formed on the other surface of the resin substrate, and a substrate (a5) having resin layers on both surfaces of the resin substrate was obtained. The mechanical properties and optical properties of the obtained substrate (a5) were evaluated. The results are shown in table 3.

[ production of optical Filter ]

In the same manner as in example a1 except that the obtained base material (a5) was used, a dielectric multilayer film (I) was formed on one surface of the base material (a5) and a dielectric multilayer film (II) was formed on the other surface, whereby an optical filter having a thickness of about 0.060mm was obtained. The optical characteristics and properties of the obtained optical filter were evaluated. The results are shown in table 3.

Comparative example A1

[ production of base Material ]

A base material (a6) was produced in the same manner as in example a1 except that the amount of resin a was changed to 100 parts by mass, and methylene chloride was used instead of hydrophobic CNF as a solvent for dissolving the resin, instead of tetrahydrofuran, and mechanical properties and optical properties were evaluated. The results are shown in table 3.

[ production of optical Filter ]

In the same manner as in example a1 except that the obtained substrate (a6) was used, a dielectric multilayer film (I) was formed on one surface of the substrate (a6) and a dielectric multilayer film (II) was formed on the other surface, whereby an optical filter having a thickness of about 0.110mm was obtained. The optical characteristics and properties of the obtained optical filter were evaluated. The results are shown in table 3.

Comparative example A2

[ production of base Material ]

A resin substrate was produced in the same manner as in example a5, except that the compound (a) was not used. The resin composition (2) was applied to one surface of the obtained resin substrate by a bar coater, and the substrate was heated at 70 ℃ for 2 minutes in an oven to evaporate and remove the solvent. At this time, the coating conditions of the bar coater were adjusted so that the thickness after drying became 5 μm. Next, exposure was carried out using a conveyer type exposure machine (exposure amount 500 mJ/cm) ² 200mW) of a resin prepared by curing the resin composition (2)A resin layer is formed on the substrate. Similarly, a resin layer containing the resin composition (2) was formed on the other surface of the resin substrate, and a substrate (a7) having resin layers on both surfaces of the resin substrate was obtained. The mechanical properties of the obtained substrate (a7) were evaluated. The results are shown in table 3.

[ production of optical Filter ]

In the same manner as in example a1 except that the obtained substrate (a7) was used, a dielectric multilayer film (I) was formed on one surface of the substrate (a7) and a dielectric multilayer film (II) was formed on the other surface, whereby an optical filter having a thickness of about 0.110mm was obtained. The optical characteristics and properties of the obtained optical filter were evaluated. The results are shown in table 3.

[ Table 3]

Example B1

[ production of base Material ]

To a vessel were added 100 parts by mass of the resin a obtained in resin synthesis example 1, 0.08 part by mass of the compound (A1) (absorption maximum wavelength in dichloromethane of 704nm) as the compound (a), 0.16 part by mass of the compound (a2) (absorption maximum wavelength in dichloromethane of 738nm), and dichloromethane, to prepare a solution having a resin concentration of 10% by mass. The solution obtained was cast onto a smooth glass plate and, after drying at 20 ℃ for 8 hours, peeled off from the glass plate. The peeled coating film was dried at 100 ℃ for 8 hours under reduced pressure to obtain a resin substrate having a thickness of 0.05mm, a vertical thickness of 210mm and a horizontal thickness of 210 mm.

On one side of the obtained resin substrate, a resin composition (3) having the following composition was applied by a bar coater, and heated at 70 ℃ for 2 minutes in an oven to evaporate and remove the solvent. At this time, the coating conditions of the bar coater were adjusted so that the thickness after drying became 10 μm. Next, exposure was carried out using a conveyer type exposure machine (exposure amount 500 mJ/cm) ² 200mW) of the resin composition (3) to form a resin layer on the resin substrate. In the same way as above, the first and second,a resin layer containing the resin composition (3) was also formed on the other surface of the resin substrate, and a base material (B1) having resin layers containing hydrophobic CNF on both surfaces of the resin substrate was obtained. The mechanical properties and optical properties of the obtained substrate (B1) were evaluated. The results are shown in table 4.

Resin composition (3): 20 parts by mass of hydrophobic CNF, 48 parts by mass of tricyclodecane dimethanol diacrylate, 32 parts by mass of dipentaerythritol hexaacrylate, 5 parts by mass of 1-hydroxycyclohexyl phenyl ketone, and 30% of isopropyl alcohol (solvent/solid content concentration (TSC))

[ production of optical Filter ]

In the same manner as in example a1 except that the obtained substrate (B1) was used, a dielectric multilayer film (I) was formed on one surface of the substrate (B1) and a dielectric multilayer film (II) was formed on the other surface, to obtain an optical filter having a thickness of about 0.080 mm. The optical characteristics and properties of the obtained optical filter were evaluated. The results are shown in table 4.

Example B2

[ production of base Material ]

A base material (B2) was obtained in the same manner as in example B1, except that the resin composition (3) was changed to the resin composition (4) described below.

Resin composition (4): 40 parts by mass of hydrophobic CNF, 36 parts by mass of tricyclodecane dimethanol diacrylate, 24 parts by mass of dipentaerythritol hexaacrylate, 5 parts by mass of 1-hydroxycyclohexyl phenyl ketone, and 30% of isopropyl alcohol (solvent/solid content concentration (TSC))

[ production of optical Filter ]

In the same manner as in example a1 except that the obtained substrate (B2) was used, a dielectric multilayer film (I) was formed on one surface of the substrate (B2) and a dielectric multilayer film (II) was formed on the other surface, to obtain an optical filter having a thickness of about 0.080 mm. The optical characteristics and properties of the obtained optical filter were evaluated. The results are shown in table 4.

Example B3

[ production of base Material ]

A base material (B3) was obtained in the same manner as in example B1, except that the resin composition (3) was changed to the following resin composition (5).

Resin composition (5): 60 parts by mass of hydrophobic CNF, 24 parts by mass of tricyclodecane dimethanol diacrylate, 16 parts by mass of dipentaerythritol hexaacrylate, 5 parts by mass of 1-hydroxycyclohexyl phenyl ketone, and 30% of isopropyl alcohol (solvent/solid content concentration (TSC))

[ production of optical Filter ]

In the same manner as in example a1 except that the obtained substrate (B3) was used, a dielectric multilayer film (I) was formed on one surface of the substrate (B3) and a dielectric multilayer film (II) was formed on the other surface, to obtain an optical filter having a thickness of about 0.080 mm. The optical characteristics and properties of the obtained optical filter were evaluated. The results are shown in table 4.

[ example B4]

[ production of base Material ]

A solution having a resin concentration of 10 mass% was prepared in the same manner as in example B1, except that the resin B was used in an amount of 100 parts by mass instead of the resin a, and 0.12 part by mass of the compound (a2) and 0.12 part by mass of the compound (a3) were used as the compound (a). Using the obtained solution, a resin substrate having a thickness of 0.05mm after drying was obtained in the same manner as in example B1.

On one side of the obtained resin substrate, a resin composition (6) having the following composition was applied by a bar coater, and the coated substrate was heated at 70 ℃ for 2 minutes in an oven to evaporate and remove the solvent. At this time, the coating conditions of the bar coater were adjusted so that the thickness after drying became 10 μm. Next, exposure was carried out using a conveyer type exposure machine (exposure amount 500 mJ/cm) ² 200mW) of the resin composition (6) was cured to form a resin layer on the resin substrate. Similarly, a resin layer containing the resin composition (6) was formed on the other surface of the resin substrate, and a substrate having resin layers containing hydrophobic CNF on both surfaces of the resin substrate was obtained (B4). The mechanical properties and optical properties of the obtained base material (B4) were evaluated. The results are shown in table 4.

Resin composition (6): 45 parts by mass of hydrophobic CNF, 55 parts by mass of tricyclodecane dimethanol diacrylate, 5 parts by mass of 1-hydroxycyclohexyl phenyl ketone, and 30% of isopropyl alcohol (solvent/solid content concentration (TSC))

[ production of optical Filter ]

In the same manner as in example a1 except that the obtained base material (B4) was used, the dielectric multilayer film (I) was formed on one surface of the base material (B4) and the dielectric multilayer film (II) was formed on the other surface thereof, to obtain an optical filter having a thickness of about 0.080 mm. The optical characteristics and properties of the obtained optical filter were evaluated. The results are shown in table 4.

Example B5

[ production of base Material ]

A near-infrared ray absorbing glass substrate ("BS-11" manufactured by Sonlang Nitz industries, Ltd., thickness 210 μm) was ground to a thickness of 150 μm, a resin composition (14) having the following composition was applied to both sides by a bar coater, and the resultant was heated in an oven at 70 ℃ for 2 minutes to volatilize and remove the solvent. At this time, the coating conditions of the bar coater were adjusted so that the thickness after drying became 10 μm. Next, exposure was carried out using a conveyor-type exposure machine (exposure amount 500 mJ/cm) ² 200mW) of the resin composition (14) to form a resin layer on the glass support. Similarly, a resin layer containing the resin composition (14) was also formed on the other surface of the glass support, and a substrate (B5) having resin layers containing hydrophobic CNF on both surfaces of the glass support was obtained. The mechanical properties and optical properties of the obtained base material (B5) were evaluated. The results are shown in table 4.

Resin composition (14): 20 parts by mass of hydrophobic CNF, 48 parts by mass of tricyclodecane dimethanol diacrylate, 32 parts by mass of dipentaerythritol hexaacrylate, 5 parts by mass of 1-hydroxycyclohexyl phenyl ketone, and 30% methyl ethyl ketone (solvent/solid content concentration (TSC))

[ production of optical Filter ]

In the same manner as in example a1 except that the obtained base material (B5) was used, a dielectric multilayer film (I) was formed on one surface of the base material (B5) and a dielectric multilayer film (II) was formed on the other surface, to obtain an optical filter having a thickness of about 0.180 mm. The optical characteristics and properties of the obtained optical filter were evaluated. The results are shown in table 4.

Comparative example B1

[ production of base Material ]

A base material (B6) having resin layers on both sides of a resin substrate was obtained in the same manner as in example B1, except that the resin composition (3) was changed to the resin composition (2).

[ production of optical Filter ]

In the same manner as in example a1 except that the obtained substrate (B6) was used, a dielectric multilayer film (I) was formed on one surface of the substrate (B6) and a dielectric multilayer film (II) was formed on the other surface, to obtain an optical filter having a thickness of about 0.080 mm. The optical characteristics and properties of the obtained optical filter were evaluated. The results are shown in table 4.

Comparative example B2

[ production of base Material ]

100 parts by mass of the resin A obtained in resin Synthesis example 1 and methylene chloride were charged into a vessel to prepare a solution having a resin concentration of 10% by mass. The solution obtained was cast onto a smooth glass plate and, after drying at 20 ℃ for 8 hours, peeled off from the glass plate. The peeled coating film was dried at 100 ℃ for 8 hours under reduced pressure to obtain a resin support having a thickness of 0.05mm, a vertical length of 210mm and a horizontal length of 210 mm.

On one side of the obtained resin support, the resin composition (1) having the above composition was applied by a bar coater, and heated in an oven at 70 ℃ for 2 minutes to evaporate the solvent. At this time, the coating conditions of the bar coater were adjusted so that the thickness after drying became 10 μm. Next, exposure was carried out using a conveyer type exposure machine (exposure amount 500 mJ/cm) ² 200mW) of the resin composition (1) was cured to form a resin layer on a resin support. Similarly, a resin layer containing the resin composition (1) was formed on the other surface of the resin support, and a substrate (B7) having resin layers on both surfaces of the resin support was obtained. The mechanical properties and optical properties of the obtained substrate (B7) were evaluated. The results are shown in table 4.

[ production of optical Filter ]

In the same manner as in example a1 except that the obtained substrate (B7) was used, a dielectric multilayer film (I) was formed on one surface of the substrate (B7) and a dielectric multilayer film (II) was formed on the other surface, to obtain an optical filter having a thickness of about 0.080 mm. The optical characteristics and properties of the obtained optical filter were evaluated. The results are shown in table 4.

Comparative example B3

[ production of base Material ]

100 parts by mass of the resin A obtained in resin Synthesis example 1 and methylene chloride were charged into a vessel to prepare a solution having a resin concentration of 14% by mass. The solution obtained was cast onto a smooth glass plate and, after drying at 20 ℃ for 8 hours, peeled off from the glass plate. Further, the peeled coating film was dried at 100 ℃ for 8 hours under reduced pressure to obtain a substrate comprising only a resin support having a thickness of 0.07mm, a vertical length of 210mm and a horizontal length of 210mm (B8).

[ production of optical Filter ]

In the same manner as in example a1 except that the obtained substrate (B8) was used, a dielectric multilayer film (I) was formed on one surface of the substrate (B8) and a dielectric multilayer film (II) was formed on the other surface, to obtain an optical filter having a thickness of about 0.080 mm. The optical characteristics and properties of the obtained optical filter were evaluated. The results are shown in table 4.

Comparative example B4

[ production of base Material ]

A near-infrared ray absorbing glass substrate ("BS-11" manufactured by Sonlang Nitz industries, Ltd., thickness 210 μm) was ground to a thickness of 120 μm, a resin composition (15) having the following composition was applied to both sides by a bar coater, and the resultant was heated in an oven at 70 ℃ for 2 minutes to volatilize and remove the solvent. At this time, the coating conditions of the bar coater were adjusted so that the thickness after drying became 10 μm. Next, exposure was carried out using a conveyer type exposure machine (exposure amount 500 mJ/cm) ² 200mW) of the resin composition (15) is cured to form a resin layer on the glass support. Similarly, a resin layer comprising the resin composition (15) is also formed on the other surface of the glass supportA substrate (B9) having resin layers containing the compound (A) on both surfaces of the glass support is obtained. The mechanical properties and optical properties of the obtained substrate (B9) were evaluated. The results are shown in table 4.

Resin composition (15): 0.30 part by mass of Compound (a1), 0.30 part by mass of Compound (a2), 48 parts by mass of Dicidol diacrylate, 32 parts by mass of dipentaerythritol hexaacrylate, 5 parts by mass of 1-hydroxycyclohexyl phenyl ketone, and methyl ethyl ketone (solvent/solid content concentration (TSC): 30%)

[ production of optical Filter ]

In the same manner as in example a1 except that the obtained base material (B9) was used, the dielectric multilayer film (I) was formed on one surface of the base material (B9) and the dielectric multilayer film (II) was formed on the other surface thereof, whereby an optical filter having a thickness of about 0.150mm was obtained. The optical characteristics and properties of the obtained optical filter were evaluated. The results are shown in table 4.

[ Table 4]

[ example C1]

[ production of base Material ]

On one side of the obtained resin support, a resin composition (7) having the following composition was applied by a bar coater, and the coated resin was heated at 70 ℃ for 2 minutes in an oven to evaporate and remove the solvent. At this time, the coating conditions of the bar coater were adjusted so that the thickness after drying became 10 μm. Next, exposure was carried out using a conveyer type exposure machine (exposure amount 500 mJ/cm) ² 200mW) of the resin composition, thereby curing the resin composition (7)A resin layer is formed on a resin support. Similarly, a resin layer containing the resin composition (7) was formed on the other surface of the resin support, and a substrate (C1) having resin layers containing the compound (a) and the hydrophobic CNF on both surfaces of the resin support was obtained. The mechanical properties and optical properties of the obtained substrate (C1) were evaluated. The results are shown in table 5.

Resin composition (7): 0.20 part by mass of compound (a1), 0.40 part by mass of compound (a2), hydrophobic CNF20, 0.65 part by mass of pigment (1) ("CIR-FS 265" manufactured by Karit (Carlit) Japan), 48 parts by mass of tricyclodecane dimethanol diacrylate, 32 parts by mass of dipentaerythritol hexaacrylate, 5 parts by mass of 1-hydroxycyclohexyl phenyl ketone, and methyl ethyl ketone (solvent, solid content concentration (TSC): 30%)

[ production of optical Filter ]

In the same manner as in example a1 except that the obtained substrate (C1) was used, a dielectric multilayer film (I) was formed on one surface of the substrate (C1) and a dielectric multilayer film (II) was formed on the other surface, to obtain an optical filter having a thickness of about 0.080 mm. The optical characteristics and properties of the obtained optical filter were evaluated. The results are shown in table 5.

[ example C2]

[ production of base Material ]

A substrate (C2) having resin layers containing the compound (a) and hydrophobic CNF on both sides of a resin support was produced in the same manner as in example C1, except that the following resin composition (8) was used instead of the resin composition (7). The mechanical properties and optical properties of the obtained base material (C2) were evaluated. The results are shown in table 5.

Resin composition (8): 0.20 part by mass of compound (a1), 0.40 part by mass of compound (a2), hydrophobic CNF60, 0.65 part by mass of pigment (2) ("CIR-FS 165" manufactured by Karit (Carlit) Japan), 24 parts by mass of tricyclodecane dimethanol diacrylate, 16 parts by mass of dipentaerythritol hexaacrylate, 5 parts by mass of 1-hydroxycyclohexyl phenyl ketone, and methyl ethyl ketone (solvent, solid content concentration (TSC): 30%)

[ production of optical Filter ]

In the same manner as in example a1 except that the obtained base material (C2) was used, the dielectric multilayer film (I) was formed on one surface of the base material (C2) and the dielectric multilayer film (II) was formed on the other surface, to obtain an optical filter having a thickness of about 0.080 mm. The optical characteristics and properties of the obtained optical filter were evaluated. The results are shown in table 5.

[ example C3]

[ production of base Material ]

100 parts by mass of the resin B obtained in resin Synthesis example 2 and methylene chloride were charged into a vessel to prepare a solution having a resin concentration of 10% by mass. The solution obtained was cast onto a smooth glass plate and, after drying at 20 ℃ for 8 hours, peeled off from the glass plate. The peeled coating film was dried at 100 ℃ for 8 hours under reduced pressure to obtain a resin support having a thickness of 0.05mm, a vertical length of 210mm and a horizontal length of 210 mm.

On one side of the obtained resin support, a resin composition (9) having the following composition was applied by a bar coater, and the resultant was heated at 70 ℃ for 2 minutes in an oven to evaporate and remove the solvent. At this time, the coating conditions of the bar coater were adjusted so that the thickness after drying became 10 μm. Next, exposure was carried out using a conveyer type exposure machine (exposure amount 500 mJ/cm) ² 200mW) of the resin composition (9) was cured to form a resin layer on a resin support. Similarly, a resin layer containing the resin composition (9) was formed on the other surface of the resin support, and a substrate (C3) having resin layers containing the compound (a) and the hydrophobic CNF on both surfaces of the resin support was obtained. The mechanical properties and optical properties of the obtained substrate (C3) were evaluated. The results are shown in table 5.

Resin composition (9): 0.30 part by mass of compound (a2), 0.30 part by mass of compound (a3), hydrophobic CNF40, 0.65 part by mass of pigment (1), 36 parts by mass of tricyclodecane dimethanol diacrylate, 24 parts by mass of dipentaerythritol hexaacrylate, 5 parts by mass of 1-hydroxycyclohexyl phenyl ketone, methyl ethyl ketone (solvent, solid content concentration (TSC): 30%)

[ production of optical Filter ]

In the same manner as in example a1 except that the obtained substrate (C3) was used, a dielectric multilayer film (I) was formed on one surface of the substrate (C3) and a dielectric multilayer film (II) was formed on the other surface, to obtain an optical filter having a thickness of about 0.080 mm. The optical characteristics and properties of the obtained optical filter were evaluated. The results are shown in table 5.

[ example C4]

[ production of base Material ]

100 parts by mass of the resin C obtained in resin Synthesis example 3 and methylene chloride were charged into a vessel to prepare a solution having a resin concentration of 10% by mass. The solution obtained was cast onto a smooth glass plate and, after drying at 20 ℃ for 8 hours, peeled off from the glass plate. The peeled coating film was dried at 100 ℃ for 8 hours under reduced pressure to obtain a resin support having a thickness of 0.05mm, a vertical length of 210mm and a horizontal length of 210 mm.

On one side of the obtained resin support, a resin composition (10) having the following composition was applied by a bar coater, and the coated resin was heated at 70 ℃ for 2 minutes in an oven to evaporate and remove the solvent. At this time, the coating conditions of the bar coater were adjusted so that the thickness after drying became 10 μm. Next, exposure was carried out using a conveyer type exposure machine (exposure amount 500 mJ/cm) ² 200mW) of the resin composition (10) is cured to form a resin layer on a resin support. Similarly, a resin layer containing the resin composition (10) was formed on the other surface of the resin support, and a substrate (C4) having resin layers containing the compound (a) and the hydrophobic CNF on both surfaces of the resin support was obtained. The mechanical properties and optical properties of the obtained substrate (C4) were evaluated. The results are shown in table 5.

Resin composition (10): 0.30 part by mass of compound (a2), 0.30 part by mass of compound (a3), hydrophobic CNF30, 0.65 part by mass of pigment (2), 42 parts by mass of tricyclodecane dimethanol diacrylate, 28 parts by mass of dipentaerythritol hexaacrylate, 5 parts by mass of 1-hydroxycyclohexyl phenyl ketone, methyl ethyl ketone (solvent, solid content concentration (TSC): 30%)

[ production of optical Filter ]

In the same manner as in example a1 except that the obtained substrate (C4) was used, a dielectric multilayer film (I) was formed on one surface of the substrate (C4) and a dielectric multilayer film (II) was formed on the other surface, to obtain an optical filter having a thickness of about 0.080 mm. The optical characteristics and properties of the obtained optical filter were evaluated. The results are shown in table 5.

[ example C5]

[ production of base Material ]

A resin composition (11) having the following composition was applied to both surfaces of a glass support (OA-10G manufactured by Nippon electric glass, thickness: 150 μm) by a bar coater, and heated at 70 ℃ for 2 minutes in an oven to volatilize and remove the solvent. At this time, the coating conditions of the bar coater were adjusted so that the thickness after drying became 10 μm. Next, exposure was carried out using a conveyer type exposure machine (exposure amount 500 mJ/cm) ² 200mW) of the resin composition (11) to form a resin layer on the glass support. Similarly, a resin layer containing the resin composition (11) was formed on the other surface of the glass support, and a substrate (C5) having resin layers containing the compound (a) and the hydrophobic CNF on both surfaces of the glass support was obtained. The mechanical properties and optical properties of the obtained substrate (C5) were evaluated. The results are shown in table 5.

Resin composition (11): 0.30 part by mass of compound (a2), 0.30 part by mass of compound (a3), hydrophobic CNF10, 0.65 part by mass of pigment (2), 54 parts by mass of tricyclodecane dimethanol diacrylate, 36 parts by mass of dipentaerythritol hexaacrylate, 5 parts by mass of 1-hydroxycyclohexyl phenyl ketone, methyl ethyl ketone (solvent, solid content concentration (TSC): 30%)

[ production of optical Filter ]

In the same manner as in example a1 except that the obtained substrate (C5) was used, a dielectric multilayer film (I) was formed on one surface of the substrate (C5) and a dielectric multilayer film (II) was formed on the other surface, to obtain an optical filter having a thickness of about 0.180 mm. The optical characteristics and properties of the obtained optical filter were evaluated. The results are shown in table 5.

[ example C6]

[ production of base Material ]

A resin composition (12) having the following composition was applied to both surfaces of a near-infrared-absorbing glass substrate ("BS-11" manufactured by Songlo Nitrosum industries, Ltd., thickness: 120 μm) by a bar coater, heated at 70 ℃ for 2 minutes in an oven, and the solvent was evaporated and removed. At this time, the coating conditions of the bar coater were adjusted so that the thickness after drying became 10 μm. Next, exposure was carried out using a conveyer type exposure machine (exposure amount 500 mJ/cm) ² 200mW) of the resin composition (12) is cured to form a resin layer on the glass support. Similarly, a resin layer containing the resin composition (12) was formed on the other surface of the glass support, and a substrate (C6) having resin layers containing the compound (a) and the hydrophobic CNF on both surfaces of the glass support was obtained. The mechanical properties and optical properties of the obtained substrate (C6) were evaluated. The results are shown in table 5.

Resin composition (12): 0.30 part by mass of compound (a1), 0.30 part by mass of compound (a2), hydrophobic CNF20, 48 parts by mass of tricyclodecane dimethanol diacrylate, 32 parts by mass of dipentaerythritol hexaacrylate, 5 parts by mass of 1-hydroxycyclohexyl phenyl ketone, methyl ethyl ketone (solvent, solid content concentration (TSC): 30%)

[ production of optical Filter ]

In the same manner as in example a1 except that the obtained substrate (C6) was used, a dielectric multilayer film (I) was formed on one surface of the substrate (C6) and a dielectric multilayer film (II) was formed on the other surface, to obtain an optical filter having a thickness of about 0.150 mm. The optical characteristics and properties of the obtained optical filter were evaluated. The results are shown in table 5.

Comparative example C1

[ production of base Material ]

A substrate (C7) having resin layers containing the compound (a) on both surfaces of a resin support was obtained in the same manner as in example C1, except that the resin composition (7) was changed to the following resin composition (13). The mechanical properties and optical properties of the obtained substrate (C7) were evaluated. The results are shown in table 5.

Resin composition (13): 0.20 part by mass of Compound (a1), 0.40 part by mass of Compound (a2), 0.65 part by mass of pigment (1), 60 parts by mass of Dicidol diacrylate, 40 parts by mass of dipentaerythritol hexaacrylate, 5 parts by mass of 1-hydroxycyclohexyl phenyl ketone, and methyl ethyl ketone (solvent, solid content concentration (TSC): 30%)

[ production of optical Filter ]

In the same manner as in example a1 except that the obtained substrate (C7) was used, a dielectric multilayer film (I) was formed on one surface of the substrate (C7) and a dielectric multilayer film (II) was formed on the other surface, to obtain an optical filter having a thickness of about 0.080 mm. The optical characteristics and properties of the obtained optical filter were evaluated. The results are shown in table 5.

Comparative example C2

[ production of base Material ]

A substrate (C8) having resin layers containing hydrophobic CNF on both sides of a resin support was obtained in the same manner as in example C1, except that the resin composition (3) was used instead of the resin composition (7). The mechanical properties and optical properties of the obtained substrate (C8) were evaluated. The results are shown in table 5.

[ production of optical Filter ]

In the same manner as in example a1 except that the obtained substrate (C8) was used, a dielectric multilayer film (I) was formed on one surface of the substrate (C8) and a dielectric multilayer film (II) was formed on the other surface, to obtain an optical filter having a thickness of about 0.080 mm. The optical characteristics and properties of the obtained optical filter were evaluated. The results are shown in table 5.

[ Table 5]

Claims

1. A substrate has a layer containing nanofibers and has an absorption maximum wavelength in the range of 600nm to 1200nm in wavelength.

2. The substrate according to claim 1, wherein the nanofibers have an average fiber diameter of 3nm to 200nm and an average fiber length of 0.2 μm to 10 μm.

3. The substrate according to claim 1 or 2, wherein the nanofibers have a specific surface area of 70m ² /g～300m ² /g。

4. The substrate according to claim 1 or 2, wherein the nanofibers have a crystallinity of 43% or more.

5. The substrate of claim 1 or 2, wherein the nanofibers are hydrophobic cellulose nanofibers that are dispersible in an organic solvent.

6. The base material according to claim 1 or 2, comprising a resin substrate containing the nanofibers and the compound (a) having an absorption maximum wavelength in a range of 600nm to 1200 nm.

7. The base material according to claim 6, wherein the content of the nanofibers is 5 to 50 parts by mass, based on 100 parts by mass of the total of the content of the resin constituting the resin substrate and the content of the nanofibers.

8. The substrate of claim 1 or 2, comprising: a substrate selected from a resin substrate and a near-infrared-absorbing glass substrate, the resin substrate containing a compound (A) having an absorption maximum wavelength in the range of 600nm to 1200 nm; and resin layers formed on both surfaces of the substrate and containing the nanofibers.

9. The substrate of claim 1 or 2, comprising: a support made of resin or glass; and resin layers formed on both surfaces of the support, and containing the nanofibers and a compound (A) having an absorption maximum wavelength in the range of 600nm to 1200 nm.

10. The base material according to claim 8, wherein the content of the nanofibers is 5 to 70 parts by mass, when the total content of the resin constituting the resin layer and the nanofibers is 100 parts by mass.

11. The base material according to claim 6, wherein the resin constituting the resin substrate is at least one resin selected from the group consisting of cyclic polyolefin resins, aromatic polyether resins, polyimide resins, fluorene polycarbonate resins, fluorene polyester resins, polycarbonate resins, polyamide resins, aromatic polyamide resins, polysulfone resins, polyethersulfone resins, polyphenylene resins, polyamideimide resins, polyethylene naphthalate resins, fluorinated aromatic polymer resins, (modified) acrylic resins, epoxy resins, silsesquioxane ultraviolet-curing resins, maleimide resins, alicyclic epoxy thermosetting resins, polyether ether ketone resins, polyarylate resins, allyl ester thermosetting resins, acrylic ultraviolet-curing resins, vinyl ultraviolet-curing resins, and resins containing silica as a main component and formed by a sol-gel method One kind of resin is less.

12. The substrate according to claim 9, wherein the resin constituting the resin layer is at least one resin selected from the group consisting of cyclic polyolefin resins, aromatic polyether resins, polyimide resins, fluorene polycarbonate resins, fluorene polyester resins, polycarbonate resins, polyamide resins, aromatic polyamide resins, polysulfone resins, polyethersulfone resins, polyphenylene resins, polyamideimide resins, polyethylene naphthalate resins, fluorinated aromatic polymer resins, (modified) acrylic resins, epoxy resins, silsesquioxane ultraviolet-curing resins, maleimide resins, alicyclic ether ketone epoxy thermosetting resins, polyether ether resins, polyarylate resins, allyl ester curing resins, acrylic ultraviolet-curing resins, vinyl ultraviolet-curing resins, and resins containing silica as a main component and formed by a sol-gel method And (3) a resin.

13. An optical filter comprising the substrate according to any one of claims 1 to 12, and a dielectric multilayer film.

14. The optical filter of claim 13 having a thickness of 150 μm or less.

15. An image pickup apparatus characterized in that: comprising an optical filter according to claim 13 or 14.

16. A camera module, characterized by: comprising an optical filter according to claim 13 or 14.