JP7807967B2 - Ethylene compounds - Google Patents

Description

The present invention relates to an ethylene compound that can absorb light in the ultraviolet to violet region.

Various compounds that absorb light in the ultraviolet to violet region have been known. For example, Patent Document 1 discloses benzophenone-based compounds, Patent Document 2 discloses merocyanine-based compounds, and Patent Document 3 discloses triazine-based compounds. Furthermore, Patent Documents 4 to 6 disclose resin compositions containing compounds that absorb light in the ultraviolet to violet region, and optical films formed from such resin compositions.

Japanese Patent Application Publication No. 7-285927 JP 2010-100787 A JP 2013-82707 A Japanese Patent Application Laid-Open No. 2003-26942 Japanese Patent Application Laid-Open No. 2003-43259 Japanese Patent Application Laid-Open No. 2019-14707

Resin compositions containing compounds that absorb light in the ultraviolet to violet region (hereinafter sometimes referred to as "UV-absorbing compounds") desirably have the UV-absorbing compounds dissolved uniformly in the resin, which facilitates imparting desired spectral and UV-absorbing properties to the cured resin. Furthermore, when the UV-absorbing compounds are dissolved in high concentrations in the resin, the desired spectral and UV-absorbing properties can be achieved even when the resin is molded into a thin film, making it suitable for use in display devices that require thinness, such as liquid crystal displays and organic electroluminescence displays. In this case, it is preferable for the UV-absorbing compounds to have excellent solubility in the resin, as this reduces the likelihood of cloudiness in the cured resin or bleeding out of the UV-absorbing compounds from the cured resin. When preparing such resin compositions, it is desirable to be able to handle the UV-absorbing compounds by dissolving them in an organic solvent at a high concentration. By mixing a solution in which the UV-absorbing compounds are dissolved at a high concentration with the resin, a resin composition in which the UV-absorbing compounds are dissolved uniformly and at a high concentration in the resin can be easily obtained.

The present invention was made in consideration of the above circumstances, and its purpose is to provide a compound that exhibits an absorption peak in the ultraviolet to violet region and has excellent solubility in organic solvents, as well as a resin composition and optical filter that contain said compound.

The present invention includes the following inventions.
[1] An ethylene compound represented by the following formula (1):

[In formula (1),
L represents an alkylene group, —O—, —S—, —SO—, a methine group (—C<) which may have an alkyl group, a tetravalent linking group of >C<, or a linking group formed by combining these;
a represents an integer of 2 or more;
Each A independently represents a group represented by the following formula (2):
The multiple groups A are linked to each other via a linking group L via six or more atoms.

[In formula (2),
^R1 represents a linear alkyl group having 2 or more carbon atoms, a branched alkyl group having 3 or more carbon atoms branched at the α-position carbon, or a branched alkyl group having 5 or more carbon atoms branched at a carbon other than the α-position,
^R2 represents a hydrogen atom or an alkyl group;
^R3 represents a hydrogen atom, an organic group, or a polar functional group, and multiple ^R3s may be the same or different from each other;
X represents a sulfur atom or an oxygen atom;
* represents the bonding site with the linking group L in formula (1).
[2] The ethylene compound according to [1], which has a maximum absorption peak at a wavelength of 340 nm or more and 400 nm or less in an absorption spectrum measured in toluene over a wavelength range of 300 nm to 600 nm.
[3] An ultraviolet absorber comprising the ethylene compound according to [1] or [2].
[4] An ethylene compound solution comprising the ethylene compound according to [1] or [2] and a solvent.
[5] A resin composition comprising the ethylene compound according to [1] or [2] and a resin component.
[6] The resin composition according to [5], further comprising a near-infrared absorbing dye and/or a visible light absorbing dye.
[7] A cured product obtained by curing the resin composition according to [5] or [6].
[8] An optical filter comprising the resin composition according to [5] or [6].
[9] A sensor comprising the optical filter according to [8].

The ethylene compound of the present invention exhibits an absorption peak in the ultraviolet (UVA) to violet region and has excellent solubility in organic solvents. The ethylene compound of the present invention is particularly capable of effectively absorbing light on the relatively long wavelength side of UVA. Therefore, when blended with a resin to form a resin composition and an optical filter, the resulting filter has a cutoff wavelength range near the border between the visible light and ultraviolet regions, effectively reducing the incidence angle dependency on the short wavelength side of the visible light region.

1 shows the absorption spectrum of ethylene compound 1 obtained in Example in toluene. 1 shows the transmission spectrum of an optical filter formed from an epoxy resin composition obtained in an example. 1 shows the transmission spectrum of an optical filter formed from polyarylate resin composition 1 obtained in an example. 1 shows the transmission spectrum of an optical filter formed from polyarylate resin composition 2 obtained in Example.

The ethylene compound of the present invention is represented by the following formula (1): The ethylene compound represented by the following formula (1) exhibits a sharp absorption peak in the ultraviolet to violet region and can function as an ultraviolet-absorbing ethylene compound.

In formula (1), L represents an alkylene group, -O-, -S-, -SO-, a methine group (-C<) which may have an alkyl group, a tetravalent linking group of >C<, or a linking group combining these; a represents an integer of 2 or greater; each A independently represents a group represented by formula (2) below; and multiple A groups are linked to each other via the linking group L via 6 or more atoms.

In formula (2), ^R1 represents a linear alkyl group having 2 or more carbon atoms, a branched alkyl group having 3 or more carbon atoms branched at the carbon at the α-position, or a branched alkyl group having 5 or more carbon atoms branched at a carbon other than the α-position; ^R2 represents a hydrogen atom or an alkyl group; ^R3 represents a hydrogen atom, an organic group, or a polar functional group; multiple ^R3s may be the same or different; X represents a sulfur atom or an oxygen atom; and * represents a bonding site with the linking group L in formula (1).

In the group A represented by formula (2), the ethylene structural moiety containing a carboxylic acid ester group (—COOR ¹ ) and a cyano group (—CN) functions as a chromophore. The ethylene compound represented by formula (1) has group A in which a carboxylic acid ester group and a cyano group are bonded to the ethylene group, and thus can effectively absorb light in the ultraviolet (UVA) to violet region, particularly UVA light on the relatively long wavelength side, for example, light in the wavelength range of 340 nm to 400 nm. Furthermore, by bonding two or more groups A to the linking group L, the molecular weight of the ethylene compound increases, raising the boiling point and improving heat resistance. Therefore, for example, even when blended with a resin and subjected to heat molding or heat curing, decomposition of the ethylene compound can be suppressed, and a high concentration of the ethylene compound can be present in the cured resin product after heat treatment. In formula (2), —COOR ¹ (or —CN) may be in either the cis or trans position relative to R ² .

In the group A, R ¹ in -COOR ¹ represents a linear alkyl group having 2 or more carbon atoms, a branched alkyl group having 3 or more carbon atoms branched at the α-position carbon, or a branched alkyl group having 5 or more carbon atoms branched at a carbon other than the α-position. By selecting an appropriate alkyl group for R ¹ in -COOR ¹ , which is a carboxylic acid ester group, the ethylene compound represented by formula (1) exhibits excellent solubility in organic solvents and resins. This facilitates the incorporation of a high concentration of the ethylene compound into the resin composition. Furthermore, even when forming a thin ultraviolet-absorbing layer from the resin composition, the ethylene compound can favorably absorb light in the ultraviolet to purple region. The ethylene compound represented by formula (1) also exhibits excellent heat resistance, enabling it to effectively absorb light in the ultraviolet to purple region in accordance with the inherent absorption spectrum of the ethylene compound, even in a cured resin product that has undergone heat treatment. The R ¹ in multiple groups A contained in the ethylene compound may be the same or different from each other.

The number of carbon atoms in the linear alkyl group for ^R1 is not particularly limited as long as it is 2 or more, but is preferably 3 or more, and more preferably 4 or more, from the viewpoint of increasing solubility in organic solvents and resins. The upper limit on the number of carbon atoms in the linear alkyl group for ^R1 is preferably 20 or less, more preferably 12 or less, and even more preferably 8 or less, from the viewpoint of increasing the extinction coefficient per unit mass of the ethylene compound, and may be 6 or less or 5 or less. Furthermore, by setting an upper limit on the number of carbon atoms in the linear alkyl group for ^R1 in this manner, the production and purification of the ethylene compound becomes easier. Examples of the linear alkyl group for ^R1 include an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, an n-nonyl group, an n-decyl group, an n-undecyl group, and an n-dodecyl group.

The branched alkyl group for ^R1 includes a branched alkyl group branched at the α-position carbon (i.e., the carbon adjacent to the oxygen atom of —COO—) and a branched alkyl group branched at a carbon other than the α-position. The branched alkyl group for ^R1 branched at the α-position carbon has 3 or more carbon atoms because it is branched. On the other hand, the branched alkyl group for ^R1 branched at a carbon other than the α-position has 5 or more carbon atoms, preferably 6 or more, and more preferably 7 or more. By specifying the number of carbon atoms in the branched alkyl group for ^R1 in this manner, the solubility of the ethylene compound in organic solvents and resins can be improved. There is no particular upper limit on the number of carbon atoms in the branched alkyl group for ^R1 , but from the viewpoint of increasing the extinction coefficient per unit mass of the ethylene compound, it is preferably 20 or less, more preferably 12 or less, and even more preferably 9 or less. When the branched alkyl group for ^R1 is branched at the α-position carbon, the branched alkyl group for ^R1 may have even fewer carbon atoms, for example, 8 or less, 6 or less, or 5 or less. By setting the upper limit of the number of carbon atoms in the branched alkyl group of ^R1 in this way, the production and purification of the ethylene compound becomes easier. Note that the branched alkyl group branched at the α-position carbon may also be branched at a carbon other than the α-position, but is preferably branched only at the α-position carbon. The branched alkyl group branched at a carbon other than the α-position is preferably branched only at a carbon other than the α-position.

Examples of the branched alkyl group branched at the carbon atom at the α-position of ^R1 include an isopropyl group, a sec-butyl group, a tert-butyl group, a 1-methylbutyl group, a 1-ethylpropyl group, a 1,1-dimethylpropyl group, a 1-methylpentyl group, a 1-ethylbutyl group, a 1,1-dimethylbutyl group, a 1-methyl-1-ethylpropyl group, a 1-methylhexyl group, a 1-ethylpentyl group, a 1,1-dimethylpentyl group, a 1-methyl-1-ethylbutyl group, and a 1,1-diethylpropyl group. Examples of branched alkyl groups branched at a carbon atom other than the α-position of ¹ include 2-methylbutyl, 3-methylbutyl, 2,2-dimethylpropyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl, 2-ethylbutyl, 2,2-dimethylbutyl, 2,3-dimethylbutyl, 3,3-dimethylbutyl, 2-methylhexyl, 3-methylhexyl, 4-methylhexyl, 5-methylhexyl, 2-ethylpentyl, 3-ethylpentyl, and 2,2-dimethylpentyl. , 2,3-dimethylpentyl group, 3,3-dimethylpentyl group, 2,4-dimethylpentyl group, 3,4-dimethylpentyl group, 4,4-dimethylpentyl group, 2-methylheptyl group, 3-methylheptyl group, 4-methylheptyl group, 5-methylheptyl group, 6-methylheptyl group, 2-ethylhexyl group, 3-ethylhexyl group, 4-ethylhexyl group, 2,2-dimethylhexyl group, 2,3-dimethylhexyl group, 2,4-dimethylhexyl group, 2,5-dimethylhexyl group, and the like.

^R2 in formula (2) represents a hydrogen atom or an alkyl group. Examples of the alkyl group for ^R2 include linear or branched alkyl groups such as methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, pentyl, hexyl, 2-ethylhexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, and tridecyl; and cyclic (alicyclic) alkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, and cyclodecyl. Some of the hydrogen atoms in the alkyl group may be substituted with an alkoxy group, an aryl group, a cyano group, a halogeno group, a hydroxyl group, a nitro group, or the like. The number of carbon atoms in the alkyl group (the number of carbon atoms excluding substituents) is preferably 1 to 20, and specifically, if it is a linear or branched alkyl group, it preferably has 1 to 20 carbon atoms, more preferably 1 to 10, and even more preferably 1 to 5 carbon atoms, and if it is a cyclic alkyl group, it preferably has 4 to 10 carbon atoms, and more preferably 5 to 8 carbon atoms. The alkyl group for ^R2 is preferably a linear or branched alkyl group, and it preferably has 1 to 3 carbon atoms, more preferably 1 to 2 carbon atoms. A hydrogen atom is particularly preferred as ^R2 . Note that ^R2 in multiple groups A contained in the ethylene compound may be the same or different from each other.

In group A represented by formula (2), the benzene ring bonded to the ethylene structural moiety functions to donate electrons to the ethylene structural moiety together with X (sulfur atom or oxygen atom) bonded to the benzene ring, thereby adjusting the absorption wavelength of the chromophore of the ethylene structural moiety to be in the ultraviolet to purple region. ^R3 bonded to the benzene ring represents a hydrogen atom, an organic group, or a polar functional group. In multiple groups A contained in the ethylene compound, ^R3 may be the same as or different from each other, and multiple ^R3s contained in each group A may be the same as or different from each other.

Examples of the organic group for ^R3 in formula (2) include an alkyl group, an alkoxy group, an alkylthio group, an alkoxycarbonyl group, an alkylsulfonyl group, an alkylsulfinyl group, an aryl group, an aralkyl group, an aryloxy group, an arylthio group, an aryloxycarbonyl group, an arylsulfonyl group, an arylsulfinyl group, a heteroaryl group, an amino group, an amide group, a sulfonamide group, a carboxy group (carboxylic acid group), a cyano group, etc. Examples of the polar functional group for ^R3 include a halogeno group, a hydroxyl group, a nitro group, a sulfo group (sulfonic acid group), etc.

For specific examples of the alkyl group for R ³ , see the above description of the alkyl group for R ^2. The alkyl group for R ³ may have a substituent, and examples of the substituent on the alkyl group include an aryl group, a heteroaryl group, a halogeno group, a hydroxyl group, a carboxyl group, an alkoxyl group, a cyano group, a nitro group, an amino group, and a sulfo group.

For specific examples of the alkyl group contained in the alkoxy group, alkylthio group, alkoxycarbonyl group, alkylsulfonyl group, and alkylsulfinyl group of ^R3 , see the description of the alkyl group of ^R3 .

Examples of the aryl group for ^R3 include a phenyl group, a biphenyl group, a naphthyl group, an anthryl group, a phenanthryl group, a pyrenyl group, and an indenyl group. The aryl group may have a substituent, and examples of the substituent that the aryl group has include an alkyl group, an alkoxy group, a heteroaryl group, a halogeno group, a halogenoalkyl group, a hydroxyl group, a cyano group, a nitro group, an amino group, a thiocyanate group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a carbamoyl group, a sulfo group, an alkylsulfinyl group, an arylsulfinyl group, an alkylsulfonyl group, an arylsulfonyl group, and a sulfamoyl group. The number of carbon atoms in the aryl group (the number of carbon atoms excluding the substituent) is preferably 6 to 20, and more preferably 6 to 12.

Examples of the aralkyl group for ^R3 include a benzyl group, a phenethyl group, a phenylpropyl group, a phenylbutyl group, a phenylpentyl group, and a naphthylmethyl group. The aryl group contained in the aralkyl group may have a substituent, and examples of the substituent on the aryl group include an alkyl group, an alkoxy group, a heteroaryl group, a halogeno group, a halogenoalkyl group, a hydroxyl group, a cyano group, a nitro group, an amino group, a thiocyanate group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a carbamoyl group, a sulfo group, an alkylsulfinyl group, an arylsulfinyl group, an alkylsulfonyl group, an arylsulfonyl group, and a sulfamoyl group. The number of carbon atoms in the aralkyl group (the number of carbon atoms excluding the substituent) is preferably 7 to 25, and more preferably 7 to 15.

For specific examples of the aryl group contained in the aryloxy group, arylthio group, aryloxycarbonyl group, arylsulfonyl group, and arylsulfinyl group of ^R3 , see the description of the aryl group of ^R3 .

Examples of the heteroaryl group for ^R3 include a thienyl group, a thiopyranyl group, an isothiochromenyl group, a pyrrolyl group, an imidazolyl group, a pyrazolyl group, a pyridyl group, a pyraridinyl group, a pyrimidinyl group, a pyridazinyl group, a thiazolyl group, an isothiazolyl group, a furanyl group, and a pyranyl group. The heteroaryl group may have a substituent, and examples of the substituent that the heteroaryl group has include an alkyl group, an alkoxy group, an aryl group, a halogeno group, a halogenoalkyl group, a hydroxyl group, a cyano group, an amino group, a nitro group, a thiocyanate group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a carbamoyl group, a sulfo group, an alkylsulfinyl group, an arylsulfinyl group, an alkylsulfonyl group, an arylsulfonyl group, and a sulfamoyl group. The number of carbon atoms in the heteroaryl group is preferably 3 to 18, and more preferably 4 to 12.

The amino group for ^R3 is represented by the formula: -NR ¹¹ R ¹² , and examples thereof include groups in which R ¹¹ and R ¹² are each independently a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, an aralkyl group, or a heteroaryl group. Specific examples of the alkyl group, aryl group, aralkyl group, and heteroaryl group are described above. Examples of the alkenyl group and alkynyl group include the alkyl group described above, in which some of the carbon-carbon single bonds are replaced with double bonds or triple bonds. These substituents may have some of the hydrogen atoms replaced with halogen atoms. Furthermore, R ¹¹ and R ¹² may be linked to each other to form a ring.

The amide group for ^R3 is represented by the formula -NH-C(=O) ^-R13 , and examples thereof include those in which ^R13 is an alkyl group, an aryl group, an aralkyl group, or a heteroaryl group. Specific examples of the alkyl group, aryl group, aralkyl group, and heteroaryl group are as described above, and some of the hydrogen atoms may be substituted with halogen atoms.

The sulfonamide group for ^R3 is represented by the formula: -NH-SO ₂ -R ¹⁴ , and examples thereof include those in which R ¹⁴ is an alkyl group, an aryl group, an aralkyl group, or a heteroaryl group. Specific examples of the alkyl group, aryl group, aralkyl group, and heteroaryl group are as described above, and some of the hydrogen atoms may be substituted with halogen atoms.

Examples of the halogeno group for ^R3 include a fluoro group, a chloro group, a bromo group, and an iodo group.

^R3 is preferably one or more selected from a hydrogen atom, an alkyl group, an alkoxy group, an alkylthio group, an aralkyl group, an aryloxy group, and an arylthio group. For example, when ^R3 is a nitrogen-containing substituent, the substituent ^R3 is likely to decompose or change to another structure upon heating or reaction, causing the ethylene compound to be colored yellow or the like, which is not preferred. From the viewpoint of enabling the ethylene compound to stably absorb light in the ultraviolet to violet region, ^R3 is preferably a hydrogen atom or an alkyl group, and the alkyl group preferably has 1 to 4 carbon atoms, more preferably 1 to 3 carbon atoms. In particular, of the four ^R3s bonded to the benzene ring of group A in formula (2), it is preferred that two or more are hydrogen atoms, more preferably three or more are hydrogen atoms, and it is particularly preferred that all four are hydrogen atoms.

X in formula (2) represents a sulfur atom or an oxygen atom, which stabilizes the ethylene compound and makes it easier to absorb light in the ultraviolet to violet region. From the perspective of effectively absorbing light in the UVA region, X is preferably a sulfur atom.

In group A represented by formula (2), X may be bonded at the ortho position, meta position, or para position relative to the ethylene structural unit. From the perspective of ease of production of the ethylene compound, it is preferable that X be bonded at the para position relative to the ethylene structural unit.

In formula (1), two or more groups A are bonded to the linking group L. By bonding two or more groups A to the linking group L, the heat resistance of the ethylene compound can be improved. The multiple groups A bonded to the linking group L may be the same or different. The linking group L is an a-valent linking group that connects a number of groups A, and can be composed of, for example, a single divalent, trivalent, or tetravalent organic group for the linking group, or a combination of these divalent, trivalent, or tetravalent organic groups for the linking group. The number a of groups A bonded to the linking group L in formula (1) is preferably 8 or less, more preferably 6 or less, and even more preferably 4 or less. From the viewpoint of easily producing a highly stable ethylene compound, a is more preferably 3 or less, and particularly preferably 2.

Examples of the linking group L include alkylene groups, -O-, -S-, -SO-, methine groups (-C<) which may have an alkyl group, tetravalent linking groups such as >C<, and linking groups that combine these. In this case, the alkylene group, -O-, -S-, and -SO- are divalent organic groups for linking groups, the methine group (-C<) which may have an alkyl group is a trivalent organic group for linking groups, and >C< is a tetravalent organic group for linking groups. In ethylene compounds, multiple groups A are bonded to such linking groups L.

In the ethylene compound represented by formula (1), multiple groups A are linked to each other via six or more atoms via the linking group L. That is, multiple groups A are linked to each other via the linking group L, and the multiple groups A are connected to each other via at least six atoms. Therefore, the linking group L has a portion where six or more atoms are connected in series between multiple groups A. When there are three or more groups A, it is preferable that each group A is linked to each other via the linking group L via six or more atoms. In the ethylene compound of the present invention, multiple groups A are linked to each other via six or more atoms via the linking group, thereby increasing the degree of freedom of movement of the linking group L and allowing the groups A to spread freely via the linking group L. Therefore, in combination with appropriately selecting the alkyl group for R ¹ in the above-mentioned COOR ¹ , the affinity for organic solvents and resins is increased, and the solubility in organic solvents and resins can be improved. As a result, it becomes easy to uniformly and highly concentrate the ethylene compound in the resin composition, and when forming an ultraviolet-absorbing layer from the resin composition, even if the layer is formed to a thin thickness, the ethylene compound can favorably absorb light in the ultraviolet to purple region. Preferably, the multiple groups A are linked to each other via the linking group L via 7 or more atoms, more preferably 8 or more atoms, and preferably 20 or less, more preferably 17 or less, even more preferably 14 or less, and even more preferably 11 or less.

The alkylene group contained in the linking group L may be a linear or branched alkylene group. Examples of the alkylene group contained in the linking group L include alkylene groups having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, and even more preferably 1 to 4 carbon atoms, such as methylene, ethylene, propylene, butylene, pentylene, hexylene, heptylene, octylene, nonylene, decylene, undecylene, dodecylene, tridecylene, tetradecylene, pentadecylene, hexadecylene, heptadecylene, and octadecylene. The alkylene group may have a substituent, such as a hydroxyl group and/or a thiol group.

In the linking group L, -O-, -S-, and -SO- are preferably not located at the terminals, and these organic groups for linking groups are preferably not adjacent. In other words, -O-, -S-, and -SO- are preferably bonded on both sides to a tetravalent linking group such as an alkylene group, a methine group (-C<), or a >C<. This can increase the stability of the ethylene compound represented by formula (1).

When the divalent linking group L is a divalent group formed by linking organic groups, examples of the divalent linking group L include a group in which an alkylene group, -O-, and an alkylene group are bonded in this order; a group in which an alkylene group, -S-, and an alkylene group are bonded in this order; a group in which an alkylene group, -SO-, and an alkylene group are bonded in this order; a group in which an alkylene group, -O-, an alkylene group, -O-, and an alkylene group are bonded in this order; and a group in which an alkylene group, -S-, an alkylene group, -S-, and an alkylene group are bonded in this order.

Examples of groups in which an alkylene group, -O-, and another alkylene group are bonded in this order include dialkyl ether residues with bonds in the alkyl moiety, such as groups in which ethylene, -O-, and propylene are bonded in this order, groups in which propylene, -O-, and propylene are bonded in this order, groups in which methylene, -O-, and butylene are bonded in this order, and groups in which butylene, -O-, and butylene are bonded in this order.

Examples of groups in which an alkylene group, -S-, and another alkylene group are bonded in this order include dialkylthiol residues with bonds in the alkyl moiety, such as groups in which ethylene, -S-, and propylene are bonded in this order, groups in which propylene, -S-, and propylene are bonded in this order, groups in which methylene, -S-, and butylene are bonded in this order, and groups in which butylene, -S-, and butylene are bonded in this order.

Examples of groups in which an alkylene group, -SO-, and another alkylene group are bonded in this order include dialkyl sulfoxide residues with bonds in the alkyl moiety, such as a group in which ethylene, -SO-, and propylene are bonded in this order, a group in which propylene, -SO-, and propylene are bonded in this order, a group in which methylene, -SO-, and butylene are bonded in this order, and a group in which butylene, -SO-, and butylene are bonded in this order.

Examples of groups in which an alkylene group, -O-, an alkylene group, -O-, and an alkylene group are bonded in this order include alkylene glycol dialkyl ether residues having bonds in the alkyl moiety, such as a group in which methylene, -O-, ethylene, -O-, and methylene are bonded in this order, a group in which ethylene, -O-, ethylene, -O-, and ethylene are bonded in this order, and a group in which propylene, -O-, propylene, -O-, and propylene are bonded in this order.

Examples of groups in which an alkylene group, -S-, an alkylene group, -S-, and an alkylene group are bonded in this order include (alkylenedithio)dialkyl residues with bonds in the alkyl moiety, such as a group in which methylene, -S-, ethylene, -S-, and methylene are bonded in this order, a group in which ethylene, -S-, ethylene, -S-, and ethylene are bonded in this order, and a group in which propylene, -S-, propylene, -S-, and propylene are bonded in this order.

The trivalent or higher organic group for linking group includes a methine group (-C<) or >C<, which may have an alkyl group. For the alkyl group of the methine group, see the explanation of the alkyl group of ^R2 above.

Examples of the linking group L having a trivalent or higher valent organic group for linking groups include a group in which three of the divalent organic groups for linking groups are bonded to a methine group (e.g., an alkanetriyl group in which three alkylene groups are bonded to a methine group), a group in which four of the divalent organic groups for linking groups are bonded to a >C< (e.g., an alkanetetrayl group in which four alkylene groups are bonded to a >C<), a tetravalent organic group for linking groups in which two methine groups are bonded to a divalent organic group for linking groups, and groups bonded to four of the divalent organic groups for linking groups, a group in which five of the divalent organic groups for linking groups are bonded to a pentavalent organic group for linking groups in which three methine groups are linked, a group in which four of the divalent organic groups for linking groups are bonded to a tetravalent organic group for linking groups in which two methine groups are linked via the divalent organic group for linking groups, and a group in which five of the divalent organic groups for linking groups are bonded to a pentavalent organic group for linking groups in which three methine groups are linked via the divalent organic group for linking groups.

From the perspective of increasing the degree of freedom of movement of the ethylene compound, the linking group L is preferably an alkylene group, -O-, -S-, -SO, or a linking group formed by combining these groups, and more preferably a divalent linking group (i.e., a is 2 in formula (1)). Furthermore, it is preferable that the alkylene group has no substituent.

The ethylene compound is preferably an ethylene compound represented by the following formula (3). Such an ethylene compound can effectively absorb light in the ultraviolet to violet region, has excellent solubility in organic solvents and resins, and is easy to produce. In the following formula (3), the explanation of R ^1a and R ^1b is as described above for R ¹ , the explanation of R ^2a and R ^2b is as described above for R ² , and the explanation of X ^a and X ^b is as described above for X.

The ethylene compound represented by the above formula (3) is more preferably one represented by the following formula (3-1) in which ^Xa and ^Xb are bonded at the para position relative to the ethylene structural unit.

The ethylene compound of the present invention preferably has a maximum absorption peak at a wavelength of 340 nm or more and 400 nm or less in its absorption spectrum measured in toluene over a wavelength range of 300 nm to 600 nm (more preferably, 300 nm to 700 nm, and even more preferably, 300 nm to 800 nm). That is, when the absorption spectrum of the ethylene compound is measured in toluene, it preferably has a peak with an absorption maximum in a wavelength range of 340 nm to 400 nm, and the absorption maximum of this absorption peak preferably reaches its maximum value in a wavelength range of 300 nm to 600 nm. Ethylene compounds that exhibit such an absorption spectrum can effectively absorb light in the ultraviolet (UVA) to violet region, particularly UVA light at longer wavelengths that penetrate the ozone layer and reach the earth's surface in greater amounts. The maximum wavelength of the absorption peak is more preferably 350 nm or more, even more preferably 355 nm or more, and more preferably 390 nm or less, and even more preferably 380 nm or less.

When the absorbance at the maximum wavelength of the maximum absorption peak is taken as 1, the ethylene compound preferably has a peak width of 100 nm or less at an absorbance of 0.5, more preferably 80 nm or less, and even more preferably 70 nm or less. If the ethylene compound exhibits such an absorption spectrum, it will be able to selectively absorb light in the ultraviolet (UVA) to violet region. The lower limit of the peak width is not particularly limited, but it may be, for example, 20 nm or more, or 30 nm or more.

When the absorbance at the maximum wavelength of the maximum absorption peak is taken as 1, the ethylene compound preferably has an average absorbance in the wavelength range of 470 nm to 600 nm (preferably a wavelength range of 450 nm to 700 nm) of 0.03 or less, more preferably 0.02 or less, and even more preferably 0.01 or less, which enables increased light transmittance over a wide range of the visible light region.

The absorption spectrum is determined by measuring absorbance at 1 nm intervals over a specified wavelength range. Absorbance values for wavelengths less than the measurement interval (1 nm) are calculated by linear interpolation from absorbance measurements at 1 nm intervals. The concentration of ethylene compounds in toluene is adjusted so that the absorbance at the maximum absorption peak is 1 ± 0.003. The average absorbance over the wavelength range of 470 nm to 600 nm is determined by averaging the absorbance values of 131 points measured at 1 nm intervals over the wavelength range of 470 nm to 600 nm.

The ethylene compound of the present invention can effectively absorb light in the ultraviolet (UVA) to violet region, and therefore can be suitably used as an ultraviolet absorber. The ultraviolet absorber may contain only one type of ethylene compound, or two or more types. In addition to the ethylene compound of the present invention, the ultraviolet absorber may also contain known ultraviolet absorbers (e.g., benzotriazole-based compounds, benzophenone-based compounds, salicylic acid-based compounds, benzoxazinone-based compounds, cyanoacrylate-based compounds, benzoxazole-based compounds, merocyanine-based compounds, triazine-based compounds, etc.).

The ethylene compound of the present invention can be used by dissolving or dispersing it in any solvent (e.g., water or an organic solvent). Therefore, the present invention also provides an ethylene compound solution containing the ethylene compound represented by formula (1) and a solvent. It is preferable to use an organic solvent as the solvent, which allows for the production of an ethylene compound solution in which the ethylene compound is dissolved at a high concentration. The ethylene compound solution of the present invention can effectively absorb light in the ultraviolet (UVA) to violet region.

Solvents used in the ethylene compound solution include ketones such as methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; esters such as ethyl acetate, propyl acetate, and butyl acetate; ethers such as tetrahydrofuran, dioxane, diethyl ether, and dibutyl ether; glycol derivatives (ether compounds, ester compounds, ether ester compounds, etc.) such as PGMEA (2-acetoxy-1-methoxypropane), ethylene glycol monobutyl ether, ethylene glycol monoethyl ether, and ethylene glycol ethyl ether acetate; amides such as N,N-dimethylacetamide; pyrrolidones such as N-methyl-pyrrolidone; aromatic hydrocarbons such as toluene and xylene; and aliphatic hydrocarbons such as cyclohexane and heptane. These solvents may be used alone or in combination of two or more.

The amount of solvent used may be set appropriately depending on the desired concentration of the ethylene compound in the ethylene compound solution. The concentration of the ethylene compound in the ethylene compound solution is preferably, for example, 5% by mass or more, more preferably 10% by mass or more, and even more preferably 15% by mass or more, thereby enabling the production of an ethylene compound solution with a high ethylene compound concentration. The upper limit of the ethylene compound concentration in the ethylene compound solution is set appropriately depending on the solubility of the ethylene compound in the solvent, and may be, for example, 50% by mass or less, 40% by mass or less, or 30% by mass or less.

The ethylene compound solution may further contain a near-infrared absorbing dye and/or a visible light absorbing dye. If the ethylene compound solution further contains a near-infrared absorbing dye and/or a visible light absorbing dye, it can effectively absorb light in the red to near-infrared region and/or light in the visible region in addition to light in the ultraviolet to violet region. For details about near-infrared absorbing dyes and visible light absorbing dyes, see the description of near-infrared absorbing dyes and visible light absorbing dyes that can be contained in the resin composition below.

Next, an example of a method for producing an ethylene compound according to the present invention will be described with reference to the following scheme. Note that the following scheme does not limit the method for producing an ethylene compound according to the present invention, and the ethylene compound of the present invention may also be produced by other schemes.

The ethylene compound of the present invention can be produced, for example, according to the scheme shown below. That is, in step [S-1], a benzaldehyde compound of formula (4) is reacted with a cyanoacetate ester of formula (8) to obtain a compound of formula (5) that provides group A. Then, in step [S-2], the compound of formula (5) is reacted with a compound of formula (9) that provides linking group L to obtain a compound of formula (7) in which group A is bonded to linking group L, i.e., the ethylene compound of the present invention. Alternatively, in step [S-3], a benzaldehyde compound of formula (4) is reacted with a compound of formula (9) that provides linking group L to obtain a compound of formula (6) in which a precursor of group A is bonded to linking group L. Then, in step [S-4], the compound of formula (6) is reacted with a cyanoacetate ester of formula (8) to obtain a compound of formula (7) in which group A is bonded to linking group L, i.e., the ethylene compound of the present invention.

In the above scheme, R ¹ to R ³ , X, and L have the same meanings as in the above formula (1) and formula (2), and the preferred embodiments are also as explained above. One of Z ¹ and Z ² represents a halogen atom -Y, and the other represents -XH. The combination of Z ¹ and Z ² is such that Z ¹ is a halogen atom -Y and Z ² is -XH, or Z ¹ is -XH and Z ² is a halogen atom -Y.

The ethylene compound of the present invention represented by formula (7) can be obtained by a production method including a step (step [S-1]) of subjecting a benzaldehyde compound of formula (4) and a cyanoacetate ester of formula (8) to a Knoevenagel condensation reaction to obtain a compound of formula (5), and a step (step [S-2]) of reacting a compound of formula (5) with a compound of formula (9) to nucleophilic substitution of X (a sulfur atom or an oxygen atom) contained in one of the compounds of formula (5) and formula (9) with a halogen atom Y contained in the other compound. In step [S-2], X (a sulfur atom or an oxygen atom) contained in one of the compounds of formula (5) and formula (9) acts nucleophilically on the carbon atom adjacent to the halogen atom Y contained in the other compound, thereby causing a nucleophilic substitution reaction between the compound of formula (5) and the compound of formula (9), and obtaining a compound of formula (7) in which a group A is bonded to a linking group L.

Step [S-1] can also be replaced with step [S-1'] of esterifying a benzaldehyde compound of formula (4) with a cyanoacetic acid derivative of formula: NC-CH ₂ -COOR ⁴ (R ⁴ represents a group that becomes R ¹ after esterification) through a Knoevenagel condensation reaction to obtain a compound of formula (5).

The ethylene compound of the present invention represented by formula (7) can also be obtained by a production method including a step (step [S-3]) of reacting a benzaldehyde compound of formula (4) with a compound of formula (9) to nucleophilically substitute X (a sulfur atom or an oxygen atom) contained in one of the compounds of formula (4) and formula (9) with a halogen atom Y contained in the other compound to obtain a compound of formula (6), and a step (step [S-4]) of subjecting the compound of formula (6) to a Knoevenagel condensation reaction with a cyanoacetate ester of formula (8). In step [S-3], X (a sulfur atom or an oxygen atom) contained in one of the compounds of formula (4) and formula (9) nucleophilically acts on the carbon atom adjacent to the halogen atom Y contained in the other compound, thereby causing a nucleophilic substitution reaction between the compound of formula (4) and the compound of formula (9), thereby obtaining a compound of formula (6) in which a precursor of group A is bonded to the linking group L.

Step [S-4] can also be replaced with step [S-4'] of esterifying a compound of formula (6) with a cyanoacetic acid derivative of formula: NC-CH ₂ -COOR ⁴ (R ⁴ represents a group that becomes R ¹ after esterification) through Knoevenagel condensation reaction to obtain a compound of formula (7).

As the compound of formula (9), compounds in which ^Z2 is —XH include 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,6-hexanedithiol, 1,7-heptanedithiol, 1,8-octanedithiol, 1,9-nonanedithiol, 1,10-decanedithiol, 6-mercapto-1-hexanol, 7-mercapto-1-hexanol, 8-mercapto-1-hexanol, triethylenediamine, 1,6-hexanediol, 1,7-heptanediol ... glycol, tetraethylene glycol, 1,2-bis(2-mercaptoethoxy)ethane, 1,3-bis(2-mercaptoethoxy)propane, 1,3-bis(2-mercaptopropoxy)propane, 1,2-bis(2-mercaptoethylthio)ethane, 1,3-bis(2-mercaptoethylthio)propane, 1,2-bis(2-hydroxyethylthio)ethane, 1,3-bis(2-hydroxyethylthio)propane, di(3-hydroxypropyl)sulfonyl compounds providing a divalent linking group L, such as 1,7-dihydroxy-4-(2-hydroxyethyl)heptane, 1,7-dimercapto-4-(2-mercaptoethyl)heptane, 1,7-dihydroxy-4-(2-mercaptoethyl)heptane, 1,7-dihydroxy-4-(3-hydroxypropyl)heptane, 1,7-dihydroxy-4-(2-mercaptoethyl)heptane, 1,7-dihydroxy-4-(3-hydroxypropyl)heptane, 1,7-dihydroxy-4-(2-hydroxyethyl)heptane, 1,7-dihydroxy-4-(3-hydroxypropyl)heptane, 1,7-dihydroxy-4-(2-hydroxyethyl)heptane, 1,7-dihydroxy-4-(2-mercaptoethyl)heptane, 1,7-dihydroxy-4-(3-hydroxypropyl)heptane, 1,7-dihydroxy-4-(2-hydroxyethyl ... and compounds that provide a tetravalent linking group L such as 1,8-dihydroxy-3,4-bis(2-hydroxyethyl)octane, 1,8-dimercapto-3,4-bis(2-mercaptoethyl)octane, 1,8-dihydroxy-3,4-bis(2-mercaptoethyl)octane, and 1,8-dihydroxy-3,4-bis(2-hydroxypropyl)octane. Examples of the compound of formula (9) in which ^Z2 is a halogen atom -Y include compounds in which -XH in the compounds of formula (9) exemplified above in which ^Z2 is -XH is replaced with a halogen atom.

The above reaction is preferably carried out in the presence of a solvent. Examples of solvents that can be used include chlorinated hydrocarbons such as chloroform and methylene chloride; aromatic hydrocarbons such as benzene, toluene, xylene, and trimethylbenzene; chlorinated aromatics such as chlorotoluene and dichlorobenzene; ethers such as tetrahydrofuran (THF), dioxane, cyclopentyl methyl ether, diisopropyl ether, and diethyl ether; nitriles such as acetonitrile, propionitrile, acrylonitrile, and butyronitrile; and alcohols such as methanol, ethanol, propanol, and butanol. These solvents may be used alone or in combination.

In the above reaction, the reaction temperature may be set appropriately, for example, preferably 0°C or higher, more preferably 5°C or higher, even more preferably 10°C or higher, and preferably 200°C or lower, more preferably 150°C or lower. The reaction may be carried out under reflux. The reaction time is not particularly limited and may be set appropriately depending on the progress of the reaction; for example, it is preferably 0.5 hours or longer, more preferably 1 hour or longer, and preferably 48 hours or shorter, more preferably 24 hours or shorter. In step [S-1] or step [S-4], the reaction is preferably carried out under an inert gas (nitrogen, argon, etc.) atmosphere.

The obtained ethylene compound may be appropriately purified, if necessary, by known purification means such as filtration, silica gel column chromatography, alumina column chromatography, sublimation, recrystallization, or crystallization.

The ethylene compound of the present invention can be mixed with a resin component to form a resin composition. Because the ethylene compound of the present invention has excellent solubility in resins, the ethylene compound can be contained in a high concentration in the resin composition. Because the ethylene compound of the present invention also has excellent solubility in organic solvents, when producing a resin composition, the ethylene compound can be dissolved in an organic solvent to prepare an ethylene compound solution, which can then be mixed with the resin component, thereby easily allowing the ethylene compound to be present uniformly and at a high concentration in the resin composition.

The resin composition containing the ethylene compound of the present invention can suppress deterioration caused by light in the ultraviolet (UVA) to violet region, and by curing it to form a resin molded product such as a film or a sheet-like molded product, it can be used in optical filters that cut light in the ultraviolet (UVA) to violet region. By using the ethylene compound of the present invention, the ethylene compound can be present in a high concentration in the resin composition, making it possible to form an optical filter that effectively absorbs light in the ultraviolet (UVA) to violet region while maintaining a thin thickness.

The ethylene compound of the present invention also has excellent heat resistance, so that it can effectively exhibit its UV absorption effect, even when blended with a thermoplastic resin and then hot-molded. Furthermore, even when exposed to UV light during storage of the resin composition or resin molded article, or during the production and processing of optical filters (e.g., vapor deposition or mounting), it is expected to protect the resin components and other components contained in the resin composition (such as the near-infrared absorbing dye described below) from the UV light and suppress deterioration of these components.

The resin composition contains at least the ethylene compound of the present invention and a resin component. The resin composition may contain only one type of ethylene compound, or two or more types. The resin composition may further contain other UV absorbers (e.g., benzotriazole-based compounds, benzophenone-based compounds, salicylic acid-based compounds, benzoxazinone-based compounds, cyanoacrylate-based compounds, benzoxazole-based compounds, merocyanine-based compounds, triazine-based compounds, etc.).

In order to achieve the desired performance, the content of the ethylene compound in the resin composition is preferably 0.01% by mass or more, more preferably 0.03% by mass or more, and even more preferably 0.1% by mass or more, based on 100% by mass of the solid content of the resin composition. Furthermore, in order to improve the moldability and film-forming properties of the resin composition, the content of the ethylene compound in the resin composition is preferably 25% by mass or less, more preferably 20% by mass or less, and even more preferably 15% by mass or less, based on 100% by mass of the solid content of the resin composition. If the resin composition also contains other UV absorbers, the total content of these is preferably within the above range. The content of the other UV absorbers is preferably 100 parts by mass or less, more preferably 60 parts by mass or less, and even more preferably 30 parts by mass or less, based on 100 parts by mass of the ethylene compound. Note that the solid content of the resin composition refers to the amount of the resin composition excluding the solvent, if the resin composition contains a solvent.

A known resin can be used as the resin component contained in the resin composition. The resin component is preferably one that is highly transparent and capable of dissolving or dispersing the ethylene compound of the present invention. If the resin composition also contains a near-infrared absorbing dye and/or a visible light absorbing dye, as described below, the resin component is preferably one that can also dissolve or disperse the dye. By selecting such a resin component, it is possible to achieve both high transmittance in the wavelength range that is desired to be transmitted and high absorbency in the wavelength range that is desired to be blocked.

The resin component can be not only a polymerized resin, but also a resin raw material (including a resin precursor, the raw material for that precursor, or the monomers that make up the resin) that is incorporated into the resin through a polymerization or crosslinking reaction when the resin composition is molded. In the present invention, any resin is included in the resin component. In the latter case, however, the ethylene compound structure may be partially or completely decomposed by unreacted materials, reactive terminal functional groups, ionic groups, catalysts, acidic or basic groups, etc., present in the reaction liquid obtained from the polymerization reaction. Therefore, if such concerns exist, it is desirable to blend an ethylene compound with a polymerized resin to form the resin composition.

It is preferable to use a highly transparent resin as the resin component, which allows the properties of the ethylene compound contained in the resin composition to be optimally utilized. Examples of resin components include (meth)acrylic resins, (meth)acrylic urethane resins, polyvinyl chloride resins, polyvinylidene chloride resins, polyolefin resins (e.g., polyethylene resins, polypropylene resins), cycloolefin resins, melamine resins, urethane resins, styrene resins, polyvinyl acetate, polyamide resins (e.g., nylon), aramid resins, polyimide resins, polyamideimide resins, alkyd resins, phenolic resins, epoxy resins, polyester resins (e.g., polybutylene terephthalate (PBT) resins, polyethylene terephthalate (PET) resins, polyarylate resins, etc.), polysulfone resins, butyral resins, polycarbonate resins, and poly Examples of suitable resins include ether resins, ABS resins (acrylonitrile butadiene styrene resins), AS resins (acrylonitrile-styrene copolymers), silicone resins, modified silicone resins (e.g., (meth)acrylic silicone resins, alkyl polysiloxane resins, silicone urethane resins, silicone polyester resins, and silicone acrylic resins), and fluorine-based resins (e.g., fluorinated aromatic polymers, polytetrafluoroethylene (PTFE), perfluoroalkoxy fluorine resins (PFA), fluorinated polyaryl ether ketones (FPEK), fluorinated polyimides (FPI), fluorinated polyamic acids (FPAA), and fluorinated polyether nitriles (FPEN)). Among these, polyimide resins, polyamide-imide resins, (meth)acrylic resins, cycloolefin resins, epoxy resins, polyester resins, polyarylate resins, polyamide resins, polycarbonate resins, polysulfone resins, and fluorinated aromatic polymers are preferred from the viewpoints of excellent transparency and heat resistance.

Polyimide resins are polymers containing imide bonds in the repeating units of their main chains. For example, they can be produced by condensation polymerization of tetracarboxylic dianhydride and diamine to obtain polyamic acid, which is then dehydrated and cyclized (imidized). Aromatic polyimides, in which aromatic rings are linked by imide bonds, are preferably used as polyimide resins. Examples of polyimide resins that can be used include Neoprim (registered trademark) manufactured by Mitsubishi Gas Chemical Company, Inc., Kapton (registered trademark) manufactured by DuPont, Aurum (registered trademark) manufactured by Mitsui Chemicals, Inc., Merdin (registered trademark) manufactured by Saint-Gobain, and the TPS (registered trademark) TI3000 series manufactured by Toray Plastics Precision Co., Ltd.

Polyamide-imide resin is a polymer containing amide and imide bonds in the repeating units of the main chain. Examples of polyamide-imide resins that can be used include Torlon (registered trademark) manufactured by Solvay Advanced Polymers, Viromax (registered trademark) manufactured by Toyobo Co., Ltd., and the TPS (registered trademark) TI5000 series manufactured by Toray Plastics Precision Co., Ltd.

(Meth)acrylic resins are polymers containing repeating units derived from (meth)acrylic acid or its derivatives. For example, resins containing repeating units derived from (meth)acrylic acid esters, such as poly(meth)acrylic acid ester resins, are preferably used. (Meth)acrylic resins containing a ring structure in the main chain are also preferred. Examples include carbonyl group-containing ring structures such as lactone ring structures, glutaric anhydride structures, glutarimide structures, maleic anhydride structures, and maleimide ring structures; and carbonyl group-free ring structures such as oxetane ring structures, azetidine ring structures, tetrahydrofuran ring structures, pyrrolidine ring structures, tetrahydropyran ring structures, and piperidine ring structures. Carbonyl group-containing ring structures also include structures containing carbonyl group derivative groups, such as imide groups. Examples of (meth)acrylic resins having a carbonyl group-containing ring structure that can be used include those described in JP 2004-168882 A, JP 2008-179677 A, WO 2005/54311 A, and JP 2007-31537 A.

Cycloolefin resins are polymers obtained by polymerizing cycloolefins as at least some of the monomer components, and are not particularly limited as long as they have an alicyclic structure in part of the main chain. Examples of cycloolefin resins that can be used include Topas (registered trademark) manufactured by Polyplastics Co., Ltd., Apel (registered trademark) manufactured by Mitsui Chemicals, Inc., Zeonex (registered trademark) and Zeonor (registered trademark) manufactured by Nippon Zeon Co., Ltd., and Arton (registered trademark) manufactured by JSR Corporation.

Epoxy resins are resins that can be cured by crosslinking epoxy compounds (prepolymers) in the presence of a curing agent or curing catalyst. Examples of epoxy compounds include aromatic epoxy compounds, aliphatic epoxy compounds, alicyclic epoxy compounds, and hydrogenated epoxy compounds. Examples include fluorene epoxy (Oxol® PG-100) manufactured by Osaka Gas Chemicals Co., Ltd., bisphenol A epoxy compound (JER® 828EL) and hydrogenated bisphenol A epoxy compound (JER® YX8000) manufactured by Mitsubishi Chemical Corporation, and alicyclic liquid epoxy compound (Celloxide® 2021P) manufactured by Daicel Corporation.

Polyester resins are polymers containing ester bonds in the repeating units of the main chain, and can be obtained, for example, by condensation polymerization of polycarboxylic acids (dicarboxylic acids) and polyalcohols (diols). Examples of polyester resins include polyethylene terephthalate, polybutylene terephthalate, polytrimethylene terephthalate, polyethylene naphthalate, and polybutylene naphthalate. Examples of suitable polyester resins include the OKP series manufactured by Osaka Gas Chemical Co., Ltd., the TRN series manufactured by Teijin Limited, Teonex (registered trademark), Rynite (registered trademark) manufactured by DuPont, Novapex (registered trademark) manufactured by Mitsubishi Chemical Corporation, Novaduran (registered trademark) manufactured by Mitsubishi Engineering Plastics Corporation, and Lumirror (registered trademark) and Toraycon (registered trademark) manufactured by Toray Industries, Inc.

Polyarylate resin is a polymer obtained by polycondensation of a dihydric phenol compound and a dibasic acid (e.g., an aromatic dicarboxylic acid such as phthalic acid), and has a repeating unit containing an aromatic ring and an ester bond in the repeating unit of the main chain. Examples of polyarylate resins that can be used include Vectran (registered trademark) manufactured by Kuraray Co., Ltd., and U-Polymer (registered trademark) and Unifiner (registered trademark) manufactured by Unitika Ltd.

Polyamide resins are polymers containing amide bonds in the repeating units of their main chains, and can be obtained, for example, by condensation polymerization of diamines and dicarboxylic acids. Polyamide resins may have an aliphatic backbone in their main chains, and nylon, for example, can be used as such an amide resin. Polyamide resins may also have an aromatic backbone, and aramid resins are known as such polyamide resins. Aramid resins are preferred because of their excellent heat resistance and high mechanical strength, and examples of such resins include Twaron (registered trademark) and Conex (registered trademark) manufactured by Teijin Limited, and Kevlar (registered trademark) and Nomex (registered trademark) manufactured by DuPont.

Polycarbonate resin is a polymer containing a carbonate group (-O-(C=O)-O-) in the repeating unit of the main chain. Examples of polycarbonate resins that can be used include Panlite (registered trademark) manufactured by Teijin Limited, Iupilon (registered trademark), Novarex (registered trademark), and Zanter (registered trademark) manufactured by Mitsubishi Engineering Plastics Corporation, and SD Polyca (registered trademark) manufactured by Sumika Styron Polycarbonate Co., Ltd.

Polysulfone resin is a polymer having repeating units containing an aromatic ring, a sulfonyl group (—SO ₂ —), and an oxygen atom. Examples of polysulfone resins that can be used include Sumikaexcel (registered trademark) PES3600P and PES4100P manufactured by Sumitomo Chemical Co., Ltd., and UDEL (registered trademark) P-1700 manufactured by Solvay Specialty Polymers.

A fluorinated aromatic polymer is a polymer having repeating units containing an aromatic ring having one or more fluorine atoms and at least one bond selected from the group consisting of an ether bond, a ketone bond, a sulfone bond, an amide bond, an imide bond, and an ester bond. Among these, a polymer essentially containing a repeating unit containing an aromatic ring having one or more fluorine atoms and an ether bond is preferred. For example, the fluorinated aromatic polymer described in JP 2008-181121 A can be used.

The resin component preferably has high transparency, which makes the resin composition more suitable for optical applications. For example, the resin component preferably has a total light transmittance of 75% or more at a thickness of 0.1 mm, more preferably 80% or more, and even more preferably 85% or more. There is no particular upper limit to the total light transmittance of the resin component; it is sufficient that the total light transmittance be 100% or less, but it may also be, for example, 95% or less. Total light transmittance is measured in accordance with JIS K 7105.

The resin component preferably has a high glass transition temperature (Tg), which can improve the heat resistance of the resin composition and various molded articles obtained from it. The glass transition temperature of the resin component is preferably, for example, 110°C or higher, more preferably 120°C or higher, and even more preferably 130°C or higher. There is no particular upper limit to the glass transition temperature of the resin component, but in order to ensure the moldability of the resin composition, a temperature of, for example, 380°C or lower is preferred.

The resin composition may contain a near-infrared absorbing dye and/or a visible light absorbing dye. If the resin composition further contains a near-infrared absorbing dye and/or a visible light absorbing dye, an optical filter with selective light transmission can be obtained from the resin composition. For example, when a resin composition contains the ethylene compound of the present invention and a near-infrared absorbing dye, it can be used as a resin composition for a selective light transmission filter that suppresses transmission of light in the ultraviolet to violet region and the red to near-infrared region and preferentially transmits light in the visible region. When a resin composition contains the ethylene compound of the present invention and a visible light absorbing dye, it can be used as a resin composition for a colored filter, a blue light reduction filter, etc.

Preferably, the near-infrared absorbing dye has an absorption maximum in the wavelength range of 600 nm to 1100 nm. More preferably, the near-infrared dye has an absorption peak in the wavelength range of 450 nm to 1100 nm in its absorption spectrum, with the absorption maximum of the absorption peak reaching its maximum value in the wavelength range of 450 nm to 1100 nm. The absorption maximum wavelength is more preferably 630 nm or longer, even more preferably 660 nm or longer, more preferably 1000 nm or shorter, even more preferably 900 nm or shorter, and even more preferably 800 nm or shorter.

Visible light absorbing dyes can be used without particular restrictions as long as they have a maximum absorption peak wavelength in the visible light region (for example, a wavelength range of more than 420 nm and less than 680 nm). In particular, it is preferable to use visible light absorbing dyes that have a maximum absorption peak wavelength in the wavelength range of 500 nm or more and less than 680 nm, where visibility is high.

The near-infrared absorbing dye and the visible light absorbing dye may be organic, inorganic, or an organic-inorganic hybrid dye (e.g., an organic compound coordinated with a metal atom or ion). Examples of near-infrared absorbing dyes and visible light absorbing dyes include squarylium dyes, croconium dyes, cyclic tetrapyrrole dyes (e.g., porphyrins, chlorins, phthalocyanines, naphthalocyanines, cholines, etc.) that may have copper (e.g., Cu(II)) or zinc (e.g., Zn(II)) as a central metal ion), cyanine dyes, azo dyes, quinone dyes, xanthene dyes, indoline dyes, arylmethane dyes, quaterrylene dyes, diimonium dyes, perylene dyes, quinacrylonitrile dyes, oxazine dyes, dipyrromethene dyes, nickel complex dyes, and copper ion dyes. These dyes may be used alone or in combination of two or more. Among these, it is preferable to use at least one selected from squarylium dyes, croconium dyes, phthalocyanines, cyanine dyes, and dipyrromethene dyes as the near-infrared absorbing dye and visible light absorbing dye, as they can effectively absorb light of the desired wavelength. It is preferable to use at least one selected from squarylium dyes, croconium dyes, phthalocyanines, and cyanine dyes as the near-infrared absorbing dye. This makes it easy to effectively absorb light in the near-infrared region and increase visible light transmittance.

In order to achieve the desired performance, the content of the near-infrared absorbing dye and visible light absorbing dye in the resin composition is preferably 0.01% by mass or more, more preferably 0.03% by mass or more, and even more preferably 0.1% by mass or more, based on 100% by mass of the solid content of the resin composition. Furthermore, in order to improve the moldability and film-forming properties of the resin composition, the content of the near-infrared absorbing dye and visible light absorbing dye in the resin composition is preferably 25% by mass or less, more preferably 20% by mass or less, and even more preferably 15% by mass or less, based on 100% by mass of the solid content of the resin composition. The total content of the ethylene compound, near-infrared absorbing dye, and visible light absorbing dye (or the total content including other UV absorbers) is preferably 30% by mass or less, more preferably 25% by mass or less, and even more preferably 20% by mass or less, based on 100% by mass of the solid content of the resin composition.

When the resin composition is used as a resin composition for a light selective transmission filter that preferentially transmits light in the visible light region, it is preferable to use, as the near-infrared absorbing dye, for example, a squarylium compound represented by the following formula (11) or a croconium compound represented by the following formula (12). In the following formulas (11) and (12), R ²¹ to R ²⁴ each independently represent a group represented by the following formula (13) or formula (14).

In formula (13), ring P represents an aromatic hydrocarbon ring, an aromatic heterocycle, or a fused ring containing these ring structures, which may have a substituent; R ³¹ to R ³³ each independently represent a hydrogen atom, an organic group, or a polar functional group; R ³² and R ³³ may be bonded to each other to form a ring; in formula (14), R ³⁴ to R ³⁸ each independently represent a hydrogen atom, an organic group, or a polar functional group; R ³⁴ and R ³⁵ , R ³⁵ and R ³⁶ , R ³⁶ and R ³⁷ , and R ³⁷ and R ³⁸ may be bonded to each other to form a ring; * represents a bonding site with the 4-membered ring in formula (11) or the 5-membered ring in formula (12).

For details of the organic groups and polar functional groups of R ³¹ to R ³⁸ , see the above description of the organic groups and polar functional groups of R ^3. When ^{R 31} to R ³⁸ are independent groups, it is preferable that R ³¹ to R ³⁸ are each independently a hydrogen atom, an alkyl group, an aryl group, an aralkyl group, an amino group, an amide group, or a hydroxy group. For details of these groups, see the above description of R ³ .

Examples of the ring structures formed by R ³² to R ³⁸ include hydrocarbon rings and heterocyclic rings. These ring structures may or may not have aromaticity, but are preferably non-aromatic hydrocarbon rings or non-aromatic heterocyclic rings. Examples of non-aromatic hydrocarbon rings include cycloalkanes such as cyclopentane, cyclohexane, and cycloheptane; and cycloalkenes such as cyclopentene, cyclohexene, cyclohexadiene (for example, 1,3-cyclohexadiene), cycloheptene, and cycloheptadiene. Examples of non-aromatic heterocyclic rings include rings in which one or more carbon atoms constituting the hydrocarbon ring as described above are replaced with at least one atom selected from N (nitrogen atom), S (sulfur atom), and O (oxygen atom). Examples of non-aromatic heterocycles include a pyrrolidine ring, a tetrahydrofuran ring, a tetrahydrothiophene ring, a piperidine ring, a tetrahydropyran ring, a tetrahydrothiopyran ring, a morpholine ring, a hexamethyleneimine ring, a hexamethylene oxide ring, a hexamethylene sulfide ring, and a heptamethyleneimine ring.

In the group of formula (13), the ring structure formed by combining R ³² and R ³³ is preferably a 4- to 9-membered unsaturated hydrocarbon ring, and among these, cycloalkane monoenes such as cyclopentene, cyclohexene, cycloheptene, cyclooctene, etc. If the group of formula (13) is configured in this way, the shoulder peak of the absorption waveform in the red to near-infrared region is reduced, and the absorption peak becomes sharper.

Examples of the aromatic hydrocarbon ring of ring P in formula (13) include a benzene ring, a naphthalene ring, a phenanthrene ring, an anthracene ring, a fluoranthene ring, and a cyclotetradecaheptaene ring. The aromatic hydrocarbon ring may have only one ring structure or two or more fused ring structures. The aromatic heterocycle of ring P contains one or more atoms selected from N (nitrogen atom), O (oxygen atom), and S (sulfur atom) in the ring structure and has aromaticity. Examples include a furan ring, a thiophene ring, a pyrrole ring, a pyrazole ring, an oxazole ring, a thiazole ring, an imidazole ring, a pyridine ring, a pyridazine ring, a pyrimidine ring, a pyrazine ring, a purine ring, and a pteridine ring. The aromatic heterocycle may have only one ring structure or two or more fused ring structures. The fused rings of ring P containing these ring structures have a structure in which an aromatic hydrocarbon ring and an aromatic heterocycle are fused together, and examples thereof include an indole ring, an isoindole ring, a benzimidazole ring, a quinoline ring, a benzopyran ring, an acridine ring, a xanthene ring, and a carbazole ring. By appropriately configuring the π-conjugated system of ring P, the absorption wavelength in the red to near-infrared region can be easily adjusted.

Ring P may have a substituent, and examples of such substituents include the organic groups and polar functional groups described above. When ring P has a substituent, the number of substituents is preferably 1 to 3, more preferably 1 or 2, and even more preferably 1. Ring P may not have a substituent.

For details about squarylium compounds and croconium compounds having a group of formula (13), see JP 2016-74649 A.

In the group represented by formula (14), it is preferable that R ³⁵ and R ³⁶ are linked to form a ring, and furthermore, R ³⁶ and R ³⁷ may be linked to form a ring. In this case, at least R ³⁴ and R ³⁸ are independent groups. When the group of formula (14) is configured in this manner, the absorption peak in the red to near-infrared region becomes sharp. The number of ring members in the ring structure formed by R ³⁵ and R ³⁶ or the ring structure formed by R ³⁶ and R ³⁷ is preferably 5 or more, more preferably 6 or more, and preferably 12 or less, more preferably 10 or less, and even more preferably 8 or less.

In the group represented by formula (14), it is preferable that R ³⁶ is an amino group, or that R ³⁶ which is an amino group is linked to R ³⁵ to form a ring, or that R 36 is also linked to R ³⁷ to form a ring. In this case, the maximum absorption wavelength shifts to the long wavelength side (for example, 685 nm or longer), and the transmittance of light in the red region is increased, making it possible to make the color of the transmitted light closer to the actual color.

Squarylium compounds and croconium compounds having a group represented by formula (14) may have benzene rings on both sides of the squarylium skeleton or croconium skeleton linked by a linking group. Examples of such compounds include the squarylium compounds disclosed in JP 2015-176046 A.

The resin composition may contain a solvent. For example, if the resin composition is a paint-formed resin composition, including a solvent makes it easier to apply the resin composition. A paint-formed resin composition can be obtained, for example, by dissolving an ethylene compound in a solvent containing a resin component, or by dispersing an ethylene compound in a solvent (dispersion medium) containing a resin component. The solvent may function as a solvent (dispersion medium) for the ethylene compound, or as a dispersion medium, but the former is preferred. The solvent may be any of the solvents that can be used in the ethylene compound solution described above.

The solvent content is preferably 50% by mass or more, more preferably 70% by mass or more, and preferably less than 100% by mass, more preferably 95% by mass or less, based on 100% by mass of the resin composition. Adjusting the solvent content within this range makes it easier to obtain a resin composition with a high ethylene compound concentration.

The resin composition may contain a surface conditioner, which can prevent appearance defects such as striations and dents from occurring in the resin layer when the resin composition is cured to form the resin layer. There are no particular restrictions on the type of surface conditioner, and siloxane-based surfactants, acetylene glycol-based surfactants, fluorine-based surfactants, acrylic leveling agents, etc. can be used. Examples of surface conditioners that can be used include the BYK (registered trademark) series manufactured by BYK-Chemie and the KF series manufactured by Shin-Etsu Chemical Co., Ltd.

The resin composition may contain a dispersant, which stabilizes the dispersibility of the ethylene compound or pigment even if it is partially dispersed in the resin composition, thereby preventing re-aggregation of the ethylene compound or pigment. The type of dispersant is not particularly limited, and examples that can be used include the EFKA series manufactured by EFKA Additives, the BYK (registered trademark) series manufactured by BYK-Chemie, the Solsperse (registered trademark) series manufactured by The Lubrizol Japan Corporation, the Disparlon (registered trademark) series manufactured by Kusumoto Chemicals, the Ajisper (registered trademark) series manufactured by Ajinomoto Fine-Techno Co., Ltd., the KP series manufactured by Shin-Etsu Chemical Co., Ltd., the Polyflow series manufactured by Kyoeisha Chemical Co., Ltd., the Megafac (registered trademark) series manufactured by DIC Corporation, and the Disper Aid series manufactured by San Nopco.

The resin composition may contain a silane coupling agent or its hydrolyzate or hydrolyzed condensate. This can improve the adhesion of the resin layer to the support when the resin composition is cured on the support to form a resin layer. Examples of silane coupling agents include silane coupling agents containing epoxy groups, amino groups, or mercapto groups, with epoxy group-containing silane coupling agents being preferred. The use of such silane coupling agents, combined with the inclusion of an ethylene compound in the resin composition, can improve the adhesion of the resin layer to the substrate. Examples of epoxy group-containing silane coupling agents include compounds containing epoxy groups and alkoxysilyl groups. Epoxy group-containing silane coupling agents may contain one or more epoxy groups, and one or more alkoxysilyl groups.

Hydrolyzed silane coupling agents can be obtained by converting alkoxysilyl groups contained in the silane coupling agent into silanol groups through hydrolysis. Hydrolyzed condensates of silane coupling agents can be obtained by dehydrating and condensing the silanol groups contained in the hydrolyzed silane coupling agent to form siloxane bonds (-Si-O-Si-). Typically, hydrolysis of a silane coupling agent produces a hydrolyzed silane coupling agent, and the silanol groups contained in the hydrolyzed silane coupling agent also undergo a dehydration and condensation reaction, easily producing a hydrolyzed condensate of the silane coupling agent. The hydrolyzed condensate of the silane coupling agent may be a dehydration and condensation product of hydrolyzed silane coupling agents of the same type, or may be a dehydration and condensation product of hydrolyzed silane coupling agents of different types.

The resin composition may contain various additives, such as plasticizers, surfactants, viscosity modifiers, thickening/gelling inhibitors, dehydrating agents, antifoaming agents, preservatives, and resistivity modifiers, as needed. It may also contain curing catalysts and curing rate modifiers for curing the resin components.

The resin composition can be cured to form a cured product. The resin composition may be one that cures through a reaction of the resin components (for example, a polymerization reaction or a crosslinking reaction), or one that cures by removing the solvent contained in the resin composition. Examples of such resin compositions include thermoplastic resin compositions that can be molded by injection molding, extrusion molding, etc., and resin compositions that have been made into paints that can be applied by spin coating, solvent casting, roll coating, spray coating, bar coating, dip coating, screen printing, flexographic printing, inkjet printing, etc.

When the resin composition is a thermoplastic resin composition, a cured product can be obtained by subjecting the resin composition to injection molding, extrusion molding, vacuum molding, compression molding, blow molding, or the like. In this method, a thermoplastic resin is used as the resin component, and an ethylene compound is blended with the thermoplastic resin, followed by heat molding to obtain a molded product. For example, the ethylene compound can be added to powder or pellets of the base resin, heated to approximately 150°C to 350°C, and melted before molding. Additionally, when kneading the resin, additives typically used in resin molding, such as plasticizers, can be added.

The shape of the cured product (molded product) is not particularly limited, but examples include planar (film, sheet, plate), granular, powdery, lumpy, particle aggregate, spherical, oval, lenticular, cubic, columnar, rod-shaped, conical, cylindrical, needle-shaped, fibrous, hollow fiber, porous, etc.

When the resin composition is a paint-formed resin composition, a liquid or paste-like resin composition containing an ethylene compound and a resin component can be applied to a support (e.g., a resin plate, film, glass plate, etc.) to obtain a film-like cured product having a thickness of 200 μm or less, or a sheet-like cured product having a thickness of more than 200 μm. The cured product obtained in this manner can be peeled from the support and handled as a film or sheet, or it can be handled integrally with the support.

The cured product of the resin composition may consist of a single resin layer (a layer formed by curing the resin composition) or multiple resin layers. When the cured product is handled as an integral part of a support, the cured product may be formed on only one side of the support, or on both sides. An integrated cured product and support can also be formed by thermocompression bonding or chemical bonding a molded product formed from the resin composition to the support.

Because the ethylene compound of the present invention has excellent heat resistance, it can optimally exhibit its UV absorbing effect even when it is blended with a thermoplastic resin and then heat-molded, or when it is integrated with a support by thermocompression bonding or chemical bonding. Furthermore, the excellent heat resistance of the ethylene compound allows it to optimally exhibit its UV absorbing effect even when molding is performed using resins that require a high-temperature thermosetting reaction (e.g., polyimide precursors, epoxy resins, acrylic resins, etc.) or resins that require high-temperature drying (e.g., resins containing high-boiling point solvents or resins with high glass transition temperatures).

The ultraviolet absorbers and resin compositions containing the ethylene compound of the present invention, as well as their cured products, can be used in building materials such as coated glass, resin glass, and interior and exterior materials; paints, adhesives; automobile parts; containers for food, medicines, cosmetics, chemicals, etc.; various films (protective films, optical films, retardation films, packaging films, agricultural films, etc.); various lenses (sunglasses, goggles, blue light-blocking glasses, medical protective glasses, etc.); telephone cable sheath materials used in electric wires, etc.; components for irradiation devices that use ultraviolet light as a light source; fibers; display components; touch panels; optical filter components; optical sensor components; surface protection components such as cover glass and cover panels; filter components that remove harmful rays from the human body; various sensor components (including those for preventing malfunction); lighting components; solar cell components; signs; and signage.

The resin composition of the present invention can be preferably used as a resin composition for forming filters used in a variety of applications, including optical devices, display devices, mechanical parts, and electrical and electronic parts. For example, the resin composition can be used in optical filters such as ultraviolet cut filters and selective light transmission filters that preferentially transmit light in the visible light region.

Imaging devices such as mobile phone cameras, digital cameras, car cameras, video cameras, and display elements (LEDs, etc.) typically use image sensors that convert subject light into electrical signals and output them. These image sensors are equipped with light-receiving elements such as CCDs (Charge Coupled Devices) and CMOSs (Complementary Metal-Oxide Semiconductors), as well as lenses. To improve performance, they also include a selective light transmission filter to remove optical noise (e.g., ghosts and flares) that interfere with image processing. Such selective light transmission filters typically have a dielectric multilayer film made up of alternating layers of high-refractive index material and low-refractive index material. By adjusting the thickness of each of the high-refractive index and low-refractive index material layers, the dielectric multilayer film can block light in a desired wavelength range.

However, because the cutoff wavelength range or transmission wavelength range of a dielectric multilayer film changes depending on the angle of incidence, changing the angle of incidence from perpendicular to oblique shifts the cutoff wavelength range or transmission wavelength range toward shorter wavelengths. As a result, dielectric multilayer films may not be able to adequately cut light in the desired wavelength range when the incident angle is oblique, or they may also cut light in the visible light range, resulting in a change in color. In particular, in recent years, there has been a strong demand for image sensors to become smaller and thinner. This has resulted in a decrease in the distance between the lens and the light-receiving element, making it necessary for the light-receiving element to receive light incident from more oblique angles. In this case, the cutoff wavelength range and transmission wavelength range become more dependent on the angle of incidence, resulting in a noticeable shift toward shorter wavelengths of light in the short wavelength range, i.e., light in the ultraviolet to violet range, which previously had little effect.

The resin composition of the present invention contains the ethylene compound described above. This ethylene compound exhibits a sharp absorption peak in the ultraviolet (UVA) to violet region. Therefore, an optical filter formed from this resin composition can selectively absorb light in the ultraviolet (UVA) to violet region and reduce incident angle dependence on the short wavelength side of the visible light region. In particular, the ethylene compound of the present invention can effectively absorb light on the relatively long wavelength side of UVA (e.g., wavelengths in the range of 340 nm to 400 nm). Therefore, an optical filter formed from the resin composition of the present invention has a cutoff wavelength range near the border between the visible light region and the ultraviolet region, effectively reducing incident angle dependence on the short wavelength side of the visible light region. If the resin composition of the present invention further contains a near-infrared absorbing dye in addition to the ethylene compound, an optical filter formed from this resin composition can reduce incident angle dependence on both the short wavelength side and the long wavelength side of the visible light region. Furthermore, because the ethylene compound contained in the optical filter has excellent heat resistance, decomposition and volatilization of the ethylene compound are suppressed when the resin composition is heat-molded or heat-cured, or when a dielectric multilayer film is formed by vapor deposition, thereby effectively blocking light in the ultraviolet to violet region. Furthermore, even if the optical filter is exposed to ultraviolet light during storage or manufacturing/processing (e.g., vapor deposition or mounting), deterioration of the resin components and near-infrared absorbing pigment caused by the ultraviolet light can be suppressed.

The optical filter may be formed from a single or multiple resin layers, or may be formed integrally with a support. A filter integrated with a support can be formed, for example, by applying a resin composition to the surface of the support (or, if there is another layer, such as a binder layer, between the support and the resin layer, to the surface of that other layer) using spin coating or solvent casting, followed by drying or curing. Alternatively, a filter may be formed by thermocompression bonding a planar molded article formed from the resin composition to the support.

The resin layer formed from the resin composition may be provided on only one side of the support, or on both sides. The thickness of the resin layer is not particularly limited, but in order to ensure the desired UV protection performance, it is preferably 0.5 μm or more, more preferably 1 μm or more, even more preferably 2 μm or more, and preferably 1 mm or less, more preferably 500 μm or less, and even more preferably 200 μm or less. When the resin layer is formed by applying a resin composition in the form of a paint onto the support, the strength of the filter can be ensured by the support, so the thickness of the resin layer can be made even thinner. When a resin layer is formed on a support, the thickness of the resin layer is preferably 50 μm or less, more preferably 20 μm or less, even more preferably 10 μm or less, and particularly preferably 5 μm or less.

The support preferably uses a transparent substrate such as a resin plate, resin film, or glass plate. The resin plate or resin film used as the support is preferably formed, for example, from the resin components described above. From the perspective of improving the heat resistance of the optical filter, it is preferable to use a glass substrate as the support. An optical filter formed in this manner can be mounted on electronic components, for example, by solder reflow. Furthermore, glass substrates are less likely to crack or warp even when exposed to high temperatures, making it easier to ensure adhesion with the resin layer. When using a glass substrate as the support, a binder layer formed, for example, from a silane coupling agent, may be provided between the support and the resin layer, thereby improving adhesion between the resin layer and the glass substrate.

The thickness of the support (substrate) is, for example, preferably 0.05 mm or more, more preferably 0.1 mm or more, in order to ensure strength, and is preferably 0.4 mm or less, more preferably 0.3 mm or less, in order to achieve a thinner structure.

A resin layer formed from a resin composition may be laminated with a second resin layer, a protective layer made of the same or a different resin as the resin layer. By providing a protective layer, the durability (decomposition resistance) of the ethylene compound contained in the resin layer can be increased. The protective layer may be provided on only one side of the resin layer, or on both sides. When the resin layer is provided on a support, the protective layer is preferably provided on the side of the resin layer opposite the support.

The optical filter may have an anti-reflective or anti-glare layer (anti-reflection film) that reduces reflections from fluorescent lights, etc., a scratch-resistant layer, a transparent substrate with other functions, or the like. The optical filter may have an ultraviolet reflective film or near-infrared reflective film on the resin layer. The ultraviolet reflective film or near-infrared reflective film is preferably provided on the light incident side of the resin layer. If the optical filter has an ultraviolet reflective film or near-infrared reflective film, it can further block ultraviolet and near-infrared rays from the light transmitted through the optical filter. The ultraviolet reflective film and near-infrared reflective film may have both ultraviolet and near-infrared reflective functions in one film.

UV-reflecting films, near-infrared-reflecting films, and anti-reflection films (visible light anti-reflection films) can be composed of dielectric multilayer films, in which high-refractive index material layers and low-refractive index material layers are alternately stacked. Therefore, when imparting such functions to an optical filter, it is preferable for the optical filter to have a dielectric multilayer film. Materials with a refractive index of 1.7 or higher can be used to compose the high-refractive index material layer, with materials typically selected in the refractive index range of 1.7 to 2.5. Examples of materials that can be used to compose the high-refractive index material layer include oxides such as titanium oxide, zinc oxide, zirconium oxide, lanthanum oxide, yttrium oxide, indium oxide, niobium oxide, tantalum oxide, tin oxide, and bismuth oxide; nitrides such as silicon nitride; mixtures of these oxides and nitrides, or mixtures doped with metals such as aluminum or copper or carbon (e.g., tin-doped indium oxide (ITO) and antimony-doped tin oxide (ATO)). Materials with a refractive index of 1.6 or lower can be used, with materials typically selected in the refractive index range of 1.2 to 1.6. Examples of materials that can be used to form the low refractive index material layer include silicon dioxide (silica), alumina, lanthanum fluoride, magnesium fluoride, and sodium aluminum hexafluoride.

The optical filter may also have an aluminum vapor deposition film, a thin film of a precious metal, or a resin film containing dispersed metal oxide microparticles primarily composed of indium oxide and containing a small amount of tin oxide.

The thickness of the optical filter is preferably, for example, 1 mm or less. This allows for adequately meeting demands for miniaturization of imaging elements, for example. The thickness of the optical filter is more preferably 500 μm or less, even more preferably 300 μm or less, and even more preferably 150 μm or less. It is also preferably 30 μm or more, and even more preferably 50 μm or more.

Optical filters can be used as one of the components of sensors such as image sensors (imaging elements), illuminance sensors, and proximity sensors. For example, image sensors are used as electronic components that convert light from a subject into electrical signals and output the signals, and examples of such sensors include CCDs (Charge Coupled Devices) and CMOSs (Complementary Metal-Oxide Semiconductors). Image sensors can be used in mobile phone cameras, digital cameras, in-vehicle cameras, surveillance cameras, display elements (LEDs, etc.), and more. Sensors contain one or more of the optical filters described above, and may also contain other filters (e.g., visible light-blocking filters, infrared-blocking filters, ultraviolet-blocking filters, etc.) and lenses as needed.

The present invention will be explained in more detail below using examples, but the present invention is not limited to the examples below, and appropriate modifications can be made within the scope of the above and below-described aims, and all such modifications are within the technical scope of the present invention.

(1) Synthesis of Compounds (1-1) Synthesis Example 1: Synthesis of Ethylene Compound 1 A 200 mL four-neck flask was charged with 4-fluorobenzaldehyde (4.98 g, 0.039 mol), 3.65 g (0.020 mol), 10.86 g (0.079 mol), and 74 g of acetonitrile. The mixture was reacted at 60°C for 12 hours under nitrogen flow (10 mL/min) while stirring with a stirring blade. After completion of the reaction, the insoluble matter was filtered off by vacuum filtration, and the solvent was removed by distillation using an evaporator. The resulting concentrate was placed in a 200 mL four-neck flask, and 10.04 g (0.079 mol) of isopropyl cyanoacetate, 3.32 g (0.039 mol), and 68 g of methanol were added thereto. The mixture was reacted under reflux conditions for 4 hours. After completion of the reaction, the solvent was distilled off using an evaporator, 300 g of methanol was added to the resulting concentrate, and the target product was isolated by recrystallization while cooling to an internal temperature of 5°C, yielding 8.3 g of powdery ethylene compound 1. The yield based on 4-fluorobenzaldehyde was 41.1 mol %. Approximately 5 mg of the resulting compound was taken and diluted with a predetermined amount of deuterated solvent (deuterated chloroform or deuterated dimethyl sulfoxide), and its structure was identified by ¹ H-NMR measurement.

(1-2) Synthesis Example 2: Synthesis of ethylene compound 2 [0049] 7.5 g of ethylene compound 2 (powder) shown in Table 1 was obtained in the same manner as in Synthesis Example 1, except that n-butyl cyanoacetate was used instead of isopropyl cyanoacetate in Synthesis Example 1. The yield based on 4-fluorobenzaldehyde was 60.4 mol%.

(1-3) Synthesis Example 3: Synthesis of ethylene compound 3 [0073] 5.1 g of ethylene compound 3 (powder) shown in Table 1 was obtained in the same manner as in Synthesis Example 1, except that tert-butyl cyanoacetate was used instead of isopropyl cyanoacetate in Synthesis Example 1. The yield based on 4-fluorobenzaldehyde was 41.1 mol%.

(1-4) Synthesis Example 4: Synthesis of ethylene compound 4 [0079] The same procedure as in Synthesis Example 1 was repeated, except that 2-ethylhexyl cyanoacetate was used instead of isopropyl cyanoacetate, and the target compound was isolated by column chromatography (developing solvent: chloroform), to obtain 6.6 g of ethylene compound 4 (liquid) shown in Table 1. The yield based on 4-fluorobenzaldehyde was 45.2 mol%.

(1-5) Synthesis Example 5: Synthesis of comparative ethylene compound 1 [0073] The same procedure as in Synthesis Example 1 was repeated, except that bis(2-mercaptoethyl) ether was used instead of 3,6-dioxa-1,8-octanedithiol, n-butyl cyanoacetate was used instead of isopropyl cyanoacetate, and the target product was isolated by column chromatography (developing solvent: chloroform), to obtain 1.3 g of comparative ethylene compound 1 shown in Table 1. The yield based on 4-fluorobenzaldehyde was 14.8 mol%.

(1-6) Synthesis Example 6: Synthesis of comparative ethylene compound 2 [0049] The same procedure as in Synthesis Example 1 was repeated, except that bis(2-mercaptoethyl) ether was used instead of 3,6-dioxa-1,8-octanedithiol, 2-ethylhexyl cyanoacetate was used instead of isopropyl cyanoacetate, and the target product was isolated by column chromatography (developing solvent: chloroform), to obtain 2.5 g of comparative ethylene compound 2 shown in Table 1. The yield based on 4-fluorobenzaldehyde was 24.2 mol%.

(1-7) Synthesis Example 7: Synthesis of comparative ethylene compound 3 [0079] The same procedure as in Synthesis Example 1 was repeated, except that methyl cyanoacetate was used instead of isopropyl cyanoacetate, and the target compound was isolated by column chromatography (developing solvent: chloroform), to obtain 3.8 g of comparative ethylene compound 3 shown in Table 1. The yield based on 4-fluorobenzaldehyde was 75.6 mol%.

(1-8) Synthesis Example 8: Synthesis of comparative ethylene compound 4 [0079] The same procedure as in Synthesis Example 1 was repeated, except that isobutyl cyanoacetate was used instead of isopropyl cyanoacetate, and the target compound was isolated by column chromatography (developing solvent: chloroform), to obtain 4.6 g of comparative ethylene compound 4 shown in Table 1. The yield based on 4-fluorobenzaldehyde was 79.6 mol%.

(2) Measurement of Absorption Spectra of Ethylene Compound Solutions The absorption spectra (transmission spectra) of toluene solutions of each ethylene compound were measured using a spectrophotometer (Shimadzu Corporation, UV-1800). The transmittance of light in the wavelength range of 300 nm to 1100 nm was measured at 1 nm intervals, and the maximum wavelength λmax of the maximum absorption peak in the wavelength range of 300 nm to 800 nm was determined. The results are summarized in Table 2. The absorption spectrum of a toluene solution of ethylene compound 1 is shown in Figure 1.

(3) Investigation of Solvent Solubility of Ethylene Compounds A predetermined amount of ethylene compound was added to methyl ethyl ketone or methyl isobutyl ketone and stirred, and the resulting solution was examined for turbidity. The ethylene compound was added to each solvent to a concentration of 5 mass%, 10 mass%, 15 mass%, or 20 mass%. Ethylene Compounds 1 to 4 did not exhibit turbidity at a concentration of 20 mass% in methyl ethyl ketone. Ethylene Compound 1 did not exhibit turbidity at a concentration of 15 mass% but exhibited turbidity at a concentration of 20 mass% in methyl isobutyl ketone, and Ethylene Compounds 2 to 4 did not exhibit turbidity even at a concentration of 20 mass%. On the other hand, Comparative Ethylene Compounds 1 to 4 exhibited turbidity at a concentration of 5 mass% in both methyl ethyl ketone and methyl isobutyl ketone. It was found that Ethylene Compounds 1 to 4 have high solubility in organic solvents.

(4) Preparation of Ethylenic Compound-Containing Epoxy Resin Composition (EP Resin) (4-1) Preparation of Cationic Curing Catalyst 255 g of Isopar (registered trademark) E solution (manufactured by Ando Parachemie Co., Ltd.) containing 7% TPB (tris(pentafluorophenyl)borane) was prepared according to the synthesis method described in WO 1997/031924. Water was added dropwise to this solution at 60°C to precipitate white crystals. After cooling to room temperature, the crystals were suction filtered and washed with n-heptane. The resulting cake was dried under reduced pressure at 60°C to obtain 18.7 g of a white crystalline TPB-water complex (TPB-containing powder). This complex had a water content of 9.2% (Karl Fischer moisture meter) and a TPB content of 90.8%. ^19F -NMR analysis and GC analysis of the dried complex were performed, but no peaks other than TPB were detected. 2.0 g of the resulting TPB-water complex was blended with 1.1 g of toluene and mixed at room temperature for 10 minutes. 2.6 g of a 2 mol/L ammonia-ethanol solution was then added, and the mixture was mixed at room temperature for 60 minutes to obtain a homogeneous solution of the TPB catalyst. This was used as a cationic curing catalyst.

(4-2) Preparation of Silane Hydrolyzate Solution 8.0 g of 3-glycidoxypropyltrimethoxysilane (ofs-6040, manufactured by Dow Corning Toray Co., Ltd.), 11.4 g of 2-propanol, and 0.2 g of distilled water were blended and mixed uniformly at 25° C. 0.4 g of formic acid was added thereto and mixed for 90 minutes to allow the hydrolysis reaction of 3-glycidoxypropyltrimethoxysilane to proceed, thereby obtaining a silane hydrolyzate solution.

(4-3) Preparation of Epoxy Resin Composition 54.3 g of 1,2-epoxy-4-(2-oxiranyl)cyclohexane adduct of 2,2-bis(hydroxymethyl)-1-butanol (EHPE3150, manufactured by Daicel Corporation) as an epoxy resin, 58.6 g of toluene and 65.0 g of 1,2,4-trimethylbenzene as solvents, 4.8 g of squarylium compound A (described in Example 1-18 of JP2016-74649A) as a near-infrared absorbing dye, 4.9 g of ethylene compound 2 obtained in Synthesis Example 2, and 0.2 g of BYK-306 (polyether-modified polydimethylsiloxane) manufactured by BYK-Chemie KK as a surface conditioner were blended and mixed uniformly at 40°C. After the temperature of the resulting mixture was lowered to 25°C, 5.4 g of pentaerythritol tetrakis(3-mercaptopropionate) (PEMP), 1.4 g of the cationic curing catalyst obtained above, and 5.4 g of the silane hydrolysate solution were added and mixed uniformly. The mixture was filtered through a 0.45 μm pore size filter (GL Sciences, non-aqueous 13N) to remove foreign matter, yielding an epoxy resin composition.

(5) Preparation of Ethylene Compound-Containing Polyarylate Resin (PAR Resin) Composition (5-1) Synthesis of Polyarylate Resin A 2-L reactor equipped with a stirring blade was charged with 10.01 g (0.044 mol) of 2,2'-bis(4-hydroxyphenyl)propane, 3.59 g (0.090 mol) of sodium hydroxide, and 300 g of ion-exchanged water. After dissolving, 0.89 g (0.009 mol) of triethylamine was added and dissolved. A solution of 3.57 g (0.021 mol) of terephthalic acid dichloride and 3.57 g (0.021 mol) of isophthalic acid dichloride dissolved in 500 g of methylene chloride was placed in a dropping funnel, which was then attached to the reactor. The solution in the reactor was stirred while maintained at 20°C, and the methylene chloride solution was added dropwise from the dropping funnel over 60 minutes. Further, a solution of 0.71 g (0.005 mol) of benzoyl chloride dissolved in 10 g of methylene chloride was added thereto and stirred for 60 minutes. The resulting reaction solution was neutralized with an aqueous acetic acid solution, the pH of the aqueous phase was adjusted to 7, and the oil and aqueous phases were separated using a separatory funnel. The resulting oil phase was added dropwise to methanol under stirring to reprecipitate the polymer, and the precipitate was collected by filtration and dried in an oven at 80°C to obtain a white solid polyarylate resin. The yield was 11.5 g. The weight average molecular weight (Mw) of the resulting polyarylate resin was 33,780 and the number average molecular weight (Mn) was 8,130. The weight average molecular weight and number average molecular weight of the polyarylate resin were polystyrene-equivalent values determined by gel permeation chromatography.

(5-2) Preparation of Polyarylate Resin Composition 1 19.7 g of the polyarylate resin obtained above was added to a mixed solvent of 69.1 g of toluene and 104.6 g of o-xylene, and then 1.2 g of the squarylium compound A described above and 0.5 g of squarylium compound B shown below as near-infrared absorbing dyes, 2.2 g of the ethylene compound 2 obtained in Synthesis Example 2, 0.1 g of BYK-310 (polyether-modified polydimethylsiloxane) manufactured by BYK-Chemie and 0.6 g of pentaerythritol tetrakis(3-mercaptopropionate) (PEMP) as surface conditioners, and 2.0 g of the silane hydrolyzate solution obtained in (4-2) were added and mixed uniformly. This was then filtered through a 0.1 μm pore size filter (GL Sciences, non-aqueous 13N) to remove foreign matter, and polyarylate resin composition 1 was obtained.

(5-3) Preparation of Polyarylate Resin Composition 2 Polyarylate resin composition 2 was obtained in the same manner as in the preparation of polyarylate resin composition 1, except that in the preparation of polyarylate resin composition 1, the amount of toluene was changed to 55.3 g and 118.4 g of 1,2,4-trimethylbenzene was used instead of o-xylene.

(6) Preparation of Optical Filters After 2 cc of each resin composition obtained above was dropped onto a glass substrate (Schott, D263Teco), a spin coater (Mikasa, 1H-D7) was used, and the rotation speed was increased to 1900 rpm over 0.2 seconds, held at that speed for 20 seconds, and then reduced to 0 rpm over 0.2 seconds to form a film of the resin composition on the glass substrate. The glass substrate on which the resin composition was formed was initially dried at 100 ° C. for 3 minutes using a precision incubator (Yamato Scientific, DH611) (before curing). Thereafter, the atmosphere was substituted with nitrogen at 50 ° C. for 30 minutes using an inert oven (Yamato Scientific, DN610I), and then heated to 190 ° C. in about 15 minutes. A resin layer (absorption layer) was formed on the glass substrate by drying at 190 ° C. for 30 minutes to 1 hour under a nitrogen atmosphere (after curing). The thickness of the resin layer formed on the glass substrate was 2 μm. The thickness of the resin layer was determined by measuring the thickness of the glass substrate on which the resin layer was formed and the thickness of the glass substrate alone with a micrometer, and then calculating the difference between the two.

(7) Measurement of Transmission (Absorption) Spectrum of Optical Filter (7-1) Measurement of Transmission Spectrum of Optical Filter For each optical filter having a resin layer formed on a glass substrate, the transmission spectrum was measured at a measurement interval of 1 nm using a spectrophotometer (Shimadzu Corporation, UV-1800) to determine the transmittance of light in the wavelength range of 300 nm to 800 nm. The transmission spectrum was measured for the optical filter before and after curing of the resin layer. The results are shown in Figures 2 to 4.

(7-2) Evaluation As shown in Figures 2, 3, and 4, the transmission spectrum of the optical filter formed from the resin composition containing the ethylene compound did not change significantly before and after curing at 190°C. These results demonstrate that the ethylene compound of the present invention has excellent heat resistance. Furthermore, no turbidity or bleed-out was observed in the cured resin of the obtained optical filter.

The ethylene compound of the present invention can be used as an ultraviolet absorber, or by blending it with a resin and forming it into a film or the like, it can be used as a light selective transmission filter that is useful for applications such as optical devices, display devices, mechanical parts, and electrical and electronic parts.

Claims (9)

An ethylene compound represented by the following formula (1):

[In formula (1),
L represents an alkylene group, —O—, —S—, —SO—, a methine group (—C<) which may have an alkyl group, a tetravalent linking group of >C<, or a linking group formed by combining these;
a represents an integer of 2 or more;
Each A independently represents a group represented by the following formula (2):
The multiple groups A are linked to each other via a linking group L via 7 or more atoms.

[In formula (2),
^R1 represents a linear alkyl group having 4 or more carbon atoms, a branched alkyl group having 3 or more carbon atoms branched at the α-position carbon, or a branched alkyl group having 7 or more carbon atoms branched at a carbon other than the α-position,
^R2 represents a hydrogen atom or an alkyl group;
^R3 represents a hydrogen atom, an organic group, or a polar functional group, and multiple ^R3s may be the same or different from each other;
X represents a sulfur atom or an oxygen atom;
* represents the bonding site with the linking group L in formula (1). The ethylene compound according to claim 1, which has a maximum absorption peak at a wavelength of 340 nm or more and 400 nm or less in an absorption spectrum measured in toluene over a wavelength range of 300 nm to 600 nm. An ultraviolet absorber containing the ethylene compound described in claim 1 or 2. An ethylene compound solution comprising the ethylene compound of claim 1 or 2 and a solvent. A resin composition comprising the ethylene compound according to claim 1 or 2 and a resin component. The resin composition according to claim 5, further comprising a near-infrared absorbing dye and/or a visible light absorbing dye. A cured product obtained by curing the resin composition described in claim 5 or 6. An optical filter comprising the resin composition described in claim 5 or 6. A sensor comprising the optical filter described in claim 8.