Ultraviolet absorber having novel crystal form, aqueous dispersion composition thereof, and sol-gel coating composition

Abstract

To provide an ultraviolet absorbing compound capable of improving ultraviolet shielding performance while maintaining high transparency, and to provide an aqueous dispersion composition and a sol-gel coating composition containing the same.SOLUTION: A specific crystal form of a 2,2'-methylene-bis[6-(2H-benzotriazol-2-yl)-4-tert-octylphenol] analogue.

Description

[Technical Field]

[0001] The present invention relates to an ultraviolet absorber having a novel crystalline form, a water-dispersed composition thereof, and a sol-gel coating composition. [Background technology]

[0002] There is a need to protect the human body, especially the skin and eyes, from ultraviolet rays. It is particularly important to block the long-wavelength UV-a rays (315nm to 400nm) that reach the dermis. For this reason, there is a demand for the functionality to block ultraviolet rays up to this long wavelength in building materials or vehicle window glass used in buildings where people mainly spend their daytime time and in automobiles, which are used as daily means of transportation.

[0003] A typical approach to imparting functionality to window glass is to use thin-film sol-gel coating. Because sol-gel coatings primarily use water-soluble solvents, UV absorbers, which are generally poorly soluble in water-soluble solvents and are used by dissolving them in organic solvents, cannot be used. Therefore, the present inventors have proposed a water-dispersed composition of a UV absorber that can be used in sol-gel coatings. The water-dispersed composition is a benzotriazole-based UV absorber with excellent UV absorption performance and photostability, particularly a benzotriazole-based UV absorber known as 2,2'-methylenebis[6-(2H-benzotriazol-2-yl)-4-tert-octylphenol] (also known as bisoctrizole), which is known as a UV absorber capable of absorbing UV light up to long wavelengths (Patent Documents 1 to 6). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-136846 [Patent Document 2] Japanese Patent Application Laid-Open No. 2012-180260 [Patent Document 3] Japanese Patent Publication No. 2020-105022 [Patent Document 4] Japanese Patent Publication No. 2022-115764 [Patent Document 5] Japanese Patent Publication No. 2022-115765 [Patent Document 6] Japanese Patent Publication No. 2022-115766 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the inventors' investigations have revealed that the ultraviolet absorber aqueous dispersion compositions prepared by these known techniques do not provide sufficient shielding of UV-a rays in the long wavelength range for the above-mentioned applications. However, if the concentration of the ultraviolet absorber in the coating film is increased or the film thickness is increased in order to improve the shielding of UV-a rays in the long wavelength range, this will result in deterioration of the film's physical properties, such as a decrease in transparency, a decrease in abrasion resistance, a decrease in hardness, and the occurrence of cracks, making it difficult to apply them to building materials or automotive window glass, which require transparency and are expected to be used under severe conditions. Therefore, there is a demand for an aqueous dispersion composition of an ultraviolet absorber that can sufficiently block UV-a rays even in small amounts while maintaining high transparency, without increasing the concentration of the ultraviolet absorber in the film or increasing the film thickness. [Means for solving the problem]

[0006] The present inventors have conducted extensive research to solve the above problems. As a result, they have found that certain benzotriazole compounds with UV-absorbing ability exist in crystalline polymorphs, and that the state of the compound in the crystal differs between crystalline polymorphs. They have also found that a certain novel crystalline form has a higher UV-a blocking effect than other crystalline forms, and that the proportion of the compound in a specific state differs from other crystalline forms. They have also found that this novel crystalline form can be identified as having a peak at a specific position in 2θ angle and no peak at other specific positions. The present inventors further discovered that by allowing this novel crystalline form to exist as fine particles in a liquid without losing its shape, it is possible to improve the ultraviolet blocking performance while maintaining high transparency, without changing the amount of ultraviolet absorber in the film or increasing the film thickness. Furthermore, they discovered that by preparing an aqueous dispersion composition using this novel crystalline form and using it as a sol-gel coating solution, it is possible to sufficiently block UV-a rays even in a thin film while maintaining high transparency.

[0007] That is, the present invention provides: (1) A crystalline form of a compound represented by the following chemical formula (I), characterized in that it exhibits a powder X-ray diffraction pattern having peaks at 2θ angles of 8.6° (±0.2°), 12.4° (±0.2°), 14.4° (±0.2°), 15.2° (±0.2°), 16.1° (±0.2°), 24.5° (±0.2°), 26.7° (±0.2°), 31.0° (±0.2°), and 33.7° (±0.2°), and no peak at 10.1° (±0.2°); (In chemical formula (I), R represents a halogen atom, and R′ represents an alkyl group having 4 to 12 carbon atoms, which may be branched or may have a substituent.) Chemical formula (I) [ka]

[0008] (2) A crystalline form of a compound represented by the following general formula (II), characterized by exhibiting a powder X-ray diffraction pattern having peaks at 2θ angles of 8.6° (±0.2°), 12.4° (±0.2°), 14.4° (±0.2°), 15.2° (±0.2°), 16.1° (±0.2°), 24.5° (±0.2°), 26.7° (±0.2°), 31.0° (±0.2°), and 33.7° (±0.2°), and no peak at 10.1° (±0.2°): Chemical formula (II) [ka] (R1, R1', R2, and R2' are any of the following (i) to (iv): (i) R1 and R1' are chlorine atoms and R2 and R2' are hydrogen atoms; (ii) R1 and R1' are hydrogen atoms and R2 and R2' are chlorine atoms; (iii) R1 and R2' are chlorine atoms and R2 and R1' are hydrogen atoms; (iv) R1 and R2' are hydrogen atoms and R2 and R1' are chlorine atoms.

[0009] (3) The crystalline form of (1) above, characterized in that the peak sizes are: a peak at 8.6° (±0.2°) > a peak at 12.4° (±0.2°), a peak at 8.6° (±0.2°) > a peak at 24.5° (±0.2°), and a peak at 14.4° (±0.2°) < a peak at 24.5° (±0.2°); (4) The crystalline form of (2) above, characterized in that the peak sizes are: a peak at 8.6° (±0.2°) > a peak at 12.4° (±0.2°), a peak at 8.6° (±0.2°) > a peak at 24.5° (±0.2°), and a peak at 14.4° (±0.2°) < a peak at 24.5° (±0.2°);

[0010] (5) A crystalline form of a compound represented by the following general formula (II), characterized in that the crystalline form contains 50% or more of the compound (ii): Chemical formula (II) [ka] (R1, R1', R2, and R2' are any of the following (i) to (iv): (i) R1 and R1' are chlorine atoms and R2 and R2' are hydrogen atoms; (ii) R1 and R1' are hydrogen atoms and R2 and R2' are chlorine atoms; (iii) R1 and R2' are chlorine atoms and R2 and R1' are hydrogen atoms; (iv) R1 and R2' are hydrogen atoms and R2 and R1' are chlorine atoms.

[0011] (6) A crystalline form of a compound represented by the following chemical formula (I), characterized in that the crystalline form is an orthorhombic system, a space group Pbcn, and has lattice constants a: 19.0217(13), b: 8.0822(6), and c: 24.494(4); (In chemical formula (I), R represents a halogen atom, and R′ represents an alkyl group having 4 to 12 carbon atoms, which may be branched or may have a substituent.) Chemical formula (I) [ka] (7) A water-dispersed composition, characterized in that the crystalline form according to any one of (1) to (6) above is dispersed in an aqueous medium. (8) A water-dispersed composition in which an ultraviolet absorber is dispersed in an aqueous medium, wherein the ultraviolet absorber contains the crystalline form described in any one of (1) to (6) above. (9) The ultraviolet absorber water dispersion composition according to (8) above, wherein the dispersed particle size of the ultraviolet absorber dispersed in the aqueous medium is 10 to 35 nm; and (10) A sol-gel coating composition comprising the crystalline form according to any one of (1) to (6) above. is located. [Effects of the Invention]

[0012] According to the present invention, it is possible to obtain a new crystalline form of an ultraviolet-absorbing compound that can exhibit high ultraviolet-shielding performance while maintaining high transparency without increasing the concentration of the ultraviolet absorber in the film or increasing the film thickness, and an aqueous dispersion composition and a sol-gel coating composition containing the same. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 shows the powder X-ray diffraction pattern of crystalline form β of the present invention. [Figure 2] FIG. 1 shows the powder X-ray diffraction pattern of crystalline form α. [Figure 3]FIG. 1 is an ORTEP diagram obtained from the results of single crystal X-ray structural analysis of crystalline form β of the present invention. [Figure 4] FIG. 1 is an ORTEP diagram obtained from the results of single crystal X-ray structural analysis of crystalline form α. [Figure 5] FIG. 1 is a diagram showing absorption spectra of Example 1, Comparative Example 1, Comparative Example 2, Comparative Example 3, and Comparative Example 4. [Figure 6] FIG. 1 is a diagram showing transmission spectra of Example 1, Comparative Example 1, Comparative Example 2, Comparative Example 3, and Comparative Example 4. DETAILED DESCRIPTION OF THE INVENTION

[0014] The present invention will be described in detail below. [Ultraviolet absorbing compound] The crystalline form of the present invention is a compound having ultraviolet absorbing ability, and is composed of a compound represented by the following general formula (I).

[0015] General formula (I) [ka]

[0016] In the chemical formula (I), R represents a halogen atom, and R' represents an alkyl group having 4 to 12 carbon atoms which may be branched or may have a substituent. Particularly preferably, R' is a tert-octyl group and R is a chlorine atom. That is, it is a compound in which chlorine atoms are introduced into the 6- or 5-position of the two benzotriazolyl groups of 2,2'-methylenebis[6-(2H-benzotriazol-2-yl)-4-tert-octylphenol] (also known as bisoctrizole). Therefore, it is represented by the following chemical formula (II). Chemical formula (II) [ka] In the formula, R1, R1', R2, and R2' are any of the following (i) to (iv). (i) R1 and R1' are chlorine atoms and R2 and R2' are hydrogen atoms; (ii) R1 and R1' are hydrogen atoms and R2 and R2' are chlorine atoms; (iii) R1 and R2' are chlorine atoms and R2 and R1' are hydrogen atoms; (iv) R1 and R2' are hydrogen atoms and R2 and R1' are chlorine atoms.

[0017] This compound itself can be produced by a method known for a long time. Many production methods are known for compounds having a benzotriazolyl skeleton, particularly dimers of benzotriazolylphenols which may have a substituent, and especially for methylenebisbenzotriazolylphenols which may have a substituent. For example, as described in German Patent 1670951, Swiss Patent 517105, Japanese Patent Laid-Open Nos. 49-6107, 61-115073, 04-290877, and 2011-6370, there are: (i) a method in which a 4-substituted phenol is condensed with an aldehyde to synthesize a bisphenol, which is then coupled with an o-nitrodiazonium salt to form an azo compound, which is then subjected to reductive cyclization; and (ii) a method in which a 4-substituted-6-benzotriazolylphenol is dimerized with formaldehyde or a derivative thereof in the presence of an acid. (iii) a method in which a 4-substituted-6-benzotriazolylphenol is reacted with an amine and an aldehyde to produce a Mannich base compound, which is then further reacted with a 4-substituted-6-benzotriazolylphenol or dimerized, (iv) a method in which a nitroamine is diazotized, coupled to a bisphenol, and the resulting nitroazophenol is subjected to alkaline reduction, and (v) a method in which a benzotriazolyl compound is reacted with formaldehyde or a derivative thereof in the presence of an acid catalyst to dimerize. These known production methods can be used without any restrictions to obtain the compound of the present invention.

[0018] After obtaining a crude product by reaction using these known methods, the crude product is generally recrystallized to obtain a powder. The present inventors have found that the crystalline form of the present invention, which is capable of exhibiting novel and excellent performance, can be obtained by setting the recrystallization conditions as follows: During recrystallization, it is preferable to use (i) toluene and / or an organic solvent with a boiling point equal to or lower than toluene, and (ii) an organic solvent with a boiling point higher than toluene, as solvents. The coexistence of these solvents allows for control of the crystal system. The ratio of the other solvent is 200 to 350 parts by weight, more preferably 250 to 300 parts by weight, and most preferably 265 to 285 parts by weight, per 100 parts by weight of (i) toluene and / or an organic solvent with a boiling point equal to or lower than toluene. The temperature during recrystallization is preferably 0 to 30° C., more preferably 0 to 15° C., and most preferably 0 to 5° C. After the compound is dissolved by heating in this manner, the temperature is lowered to precipitate crystals, thereby obtaining the novel crystalline benzotriazole compound of the present invention.

[0019] [Peaks in powder X-ray diffraction patterns and crystal structure] The novel crystalline form of the present invention thus obtained has the following characteristics: First, (1) a powder X-ray diffraction pattern is shown, which has peaks at 2θ angles of 8.6° (±0.2°), 12.4° (±0.2°), 14.4° (±0.2°), 15.2° (±0.2°), 16.1° (±0.2°), 24.5° (±0.2°), 26.7° (±0.2°), 31.0° (±0.2°), and 33.7° (±0.2°), and does not have a peak at 10.1° (±0.2°). Particularly preferably, the magnitude of the peaks is such that the peak at 8.6° (±0.2°) is greater than the peak at 12.4° (±0.2°), the peak at 8.6° (±0.2°) is greater than the peak at 24.5° (±0.2°), and the peak at 14.4° (±0.2°) is less than the peak at 24.5° (±0.2°). The novel crystalline form of the present invention is an orthorhombic crystal, has a space group of Pbcn, and has lattice constants of a: 19.0217(13), b: 8.0822(6), and c: 24.494(4). The method for identifying the peaks in the powder X-ray diffraction pattern and the crystal structure is not particularly limited, and known methods, such as those described in the examples of the present application, can be used.

[0020] [Position of chlorine in the chemical formula] The compound represented by chemical formula (II) can have variations in configuration (i) to (iv) depending on the position of the chlorine atom. However, because the benzotriazolyl group can rotate around the C-N bond in the molecular state, (i) to (iv) cannot be distinguished. Therefore, for example, this compound dissolves in a low-polarity organic solvent such as toluene and exists as a molecule, but 1H, 13C NMR and absorption spectroscopy in the dissolved state confirm that it does not have a fixed structure among (i) to (iv). In contrast, in the crystalline state, the molecule is fixed in one of the above configurations (i) to (iv). It has been revealed that the novel crystalline form of the present invention contains a large proportion of (ii) out of (i) to (iv), i.e., R1 and R1' are hydrogen atoms and R2 and R2' are chlorine atoms. Specifically, it is possible to achieve a proportion of 50% or more, or even 60% or more, or 65% or more. It is believed that by containing 50% or more of molecules in state (ii) in the crystal, the molecules are packed in a specific shape, resulting in the above-mentioned pattern in X-ray diffraction.

[0021] [UV absorber water dispersion composition] The compound in the crystalline form described above can be mixed with, for example, a surfactant, a polymer dispersant, and an aqueous medium to prepare the water-dispersed composition of the present invention. That is, the water-dispersed composition is characterized in that the crystalline form described above is dispersed in an aqueous medium. Furthermore, since this crystalline compound has ultraviolet absorption ability, the water-dispersed composition is a water-dispersed composition in which an ultraviolet absorber is dispersed in an aqueous medium, and the ultraviolet absorber contains the crystalline form described above. Here, it is preferable that this compound has a dispersed particle size of 10 to 35 nm in the aqueous medium. Below, the components of the water-dispersed composition and the production method thereof are described.

[0022] [Surfactant] The aqueous dispersion composition of the present invention preferably contains a surfactant. As surfactant, for example, ionic surfactant, nonionic surfactant and cationic surfactant can be mentioned.As ionic surfactant, for example, fatty acid salt, alkyl sulfate ester salt, alkyl benzene sulfonate salt, alkyl naphthalene sulfonate, alkyl sulfosuccinate salt, alkyl diphenyl ether disulfonate salt, polyoxyethylene alkyl sulfate ester salt, polyoxyethylene alkyl aryl sulfate ester salt, alkane sulfonate salt, naphthalene sulfonic acid formalin condensate, polyoxyethylene alkyl phosphate ester salt, N-methyl-oleoyl taurate salt, α-olefin sulfonate salt. Examples of nonionic surfactants include polyoxyethylene alkyl ethers, polyoxyethylene alkylaryl ethers, polyoxyethylene derivatives, ethylene oxide-propylene oxide block copolymers, sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene sorbitol fatty acid esters, glycerin fatty acid esters, polyoxyethylene fatty acid esters, polyoxyethylene alkylamines, acetylene glycols, and ethylene glycol adducts of acetylene glycols. Examples of cationic surfactants and amphoteric surfactants include alkylamine salts, quaternary ammonium salts, alkyl betaines, and amine oxides. These ionic surfactants may be used as dispersants, wetting agents, detergents, and surface tension adjusters, as described below.

[0023] Particularly preferred surfactants are polyoxyalkylene derivatives having an HLB of 9 to 16, preferably 11 to 15, and most preferably 13.2, containing 1 to 3 benzyl groups which may be bonded to any part of the phenyl ether ring, and the hydrophilic group may contain ethylene oxide or propylene oxide, or the ethylene oxide or propylene oxide may contain -SO3NH4, -PO3H2 or other ionic groups at the terminal.

[0024] Commercially available products include Emulgen A-60, Emulgen A-90, and Emulgen B-66 manufactured by Kao, TS1500, TS2000, and TS2600 manufactured by Toho Chemical, and Emulsogen TS160 and Dispersing Agent manufactured by Clariant. LFH, LFES, Nippon Nyukazai's Newcol 704, 706, 707, 708, 709, 710, 711, 712, 714, 714(80), 719, 610, 610(80), 2604, 2607, 2609, 2614, 707-F, 710-F, 714-F, 2608-F, 2600-FB, 2616-F, 3612-FA, 707-SF, 707-SFC, 707-SN, 714-SF, 714-SN, 723-SF, 740-SF, 780-SF, 2 Examples of suitable products include 607-SF, 2614-SF, Newcalgen C-150, C-173, C-200, C-314, CP-50, CP-80, CP-120, CP-15-200, Paionin D-6112, D-6512, D-6414, and DTD-51 manufactured by Takemoto Oils and Fats, Trimin CB#32 manufactured by Miyoshi Oils and Fats, and Hitenol NF-13, Plysurf AL, Noigen EA-87, EA-137, EA-157, EA-167, and EA-177 manufactured by Daiichi Kogyo Seiyaku. Emulgen B66 is the most preferred.

[0025] [Polymer dispersant] Furthermore, in addition to the surfactants, polymer dispersants may be used in combination, and preferred polymer dispersants include acrylic copolymers obtained by control polymerization. Commercially available products that can be used include disperbyk-190, 2010, 2012, 2013, 2015, 2055, 2060, 2061, and 2096 manufactured by BYK, and ZETASPERSE 3800 and TEGO Dispers 750W manufactured by EVONIC. Disperbyk-190 and 2015 are preferred, and disperbyk-2015 is most preferred, as they have high compatibility with surfactants used in combination and improve dispersibility compared to when the surfactant is used alone.

[0026] [Dispersion medium] In the present invention, at least the above components are dispersed in water. If a dispersion medium other than water is contained, the ultraviolet absorber may dissolve, causing a problem of wavelength shift to shorter wavelengths, so it is preferable to contain as little dispersion medium other than water as possible. It is desirable to keep the content of the dispersion medium to 1% by weight or less in the aqueous dispersion composition, and preferably the dispersion medium is 100% water.

[0027] [Content of each ingredient] The content of the ultraviolet absorber in the aqueous dispersion composition is preferably 5 to 20% by mass. If it is less than 5%, shear is not applied and dispersion does not progress easily, and if it exceeds 20% by mass, the viscosity increases and dispersion does not progress easily. It is preferably 8 to 12% by mass, and most preferably 10% by mass. The content of the surfactant is preferably 1 to 100 parts by mass relative to 100 parts by mass of the ultraviolet absorber. If the content of this surfactant is less than 1 part by mass, problems such as the progress of crushing to 50 nm or less becoming difficult and the dispersion time becoming long arise, while if the content exceeds 100 parts by mass, the viscosity becomes high and the progress of dispersion becomes difficult. It is preferably 50 to 90 parts by mass, and most preferably 70 parts by mass.

[0028] When a polymer dispersant is used in combination with a surfactant, it is preferable to use 1 to 100 parts by mass of the surfactant per 100 parts by mass of the UV absorber, within the above surfactant content range. If the amount is less than 1 part by mass, the effect of the combination is small, and if it exceeds 100 parts by mass, the viscosity increases and dispersion becomes difficult to proceed. The amount is preferably 5 to 20 parts by mass, and most preferably 10 parts by mass.

[0029] The method for preparing the ultraviolet absorber water dispersion composition using the above components is not particularly limited, but it can be produced using, for example, a device such as a media type disperser or a collision type disperser.

[0030] A media-type disperser is a disperser that disperses by moving small-diameter media such as glass, alumina, zirconia, steel, or tungsten at high speed within a vessel and grinding the slurry passing between them with the shear force between the media. Specific examples of media-type dispersers include ball mills, sand mills, pearl mills, spike mills, agitator mills, Cobo mills, and Ultra Visco mills. More specifically, examples include the Ultra Apex Mill and Wide Separator Mill manufactured by Hiroshima Metal & Machinery Co., Ltd., the MAX Nano Getter and Mugen Flow MGF manufactured by Ashizawa Finetech Co., Ltd., and the Dyno Mill ECM type manufactured by Shinmaru Enterprises Co., Ltd.

[0031] An impact-type disperser is a disperser that disperses pigments and the like in a fluid by causing a fluid to collide with one wall at high speed or by causing fluids to collide with each other at high speed, thereby pulverizing the pigments and the like in the fluid. Examples of impact-type dispersers include a jet mill that accelerates and pulverizes raw material particles using a high-speed jet stream, and the wet-type atomization device "STARBURST" (registered trademark, manufactured by Sugino Machine Co., Ltd.). Other known dispersing devices, such as a roll mill or an ultrasonic disperser, may also be used for production. Of the various dispersing devices described above, any device and media that can generate sufficient shear force to obtain the desired particle size are sufficient, and various media-type dispersers are generally suitable. These devices and media are appropriately selected, and the aforementioned components are added and processed until the ultraviolet absorber becomes fine particles having the aforementioned desired particle size.

[0032] [Physical Properties of UV Absorber Water Dispersion Composition] 1.Transparency To obtain a coating composition with desirable physical properties, it is desirable that the ultraviolet absorber water-dispersed composition satisfy the following criteria. By doing so, the resulting coating composition can maintain sufficient ultraviolet absorption performance. Furthermore, by using a transparent resin component, a composition with even better transparency can be obtained. That is, this can be confirmed by the following two criteria. First, the ultraviolet absorber water dispersion composition is diluted with water so that the ultraviolet absorber concentration becomes 0.0982%, and the transmission spectrum is measured at room temperature using a ultraviolet-visible spectrophotometer (Shimadzu Corporation, UV-1850) to confirm the transmittance at 600 nm.

[0033] The ultraviolet absorbent water dispersion composition containing the specific compound used in the present invention can achieve a transmittance of 75% or more at 600 nm measured by the above-mentioned measurement method. Furthermore, it can be 80% or more. In addition, an aqueous dispersion composition having a transmittance of less than 75% at 600 nm measured by the above-mentioned method becomes turbid and has low transparency, but as shown in the comparative examples described below, it is difficult to achieve a transmittance of 75% or more using conventional techniques. Furthermore, by setting the transmittance at 600 nm measured by the above-mentioned method in the ultraviolet absorber aqueous dispersion composition within the above range and using such an ultraviolet absorber aqueous dispersion composition, the coating composition of the present invention can maintain its ultraviolet absorption performance for a long period of time, and as a result, a coating film with excellent light resistance can be obtained.

[0034] Furthermore, when the ultraviolet absorber water dispersion composition containing the specific compound used in the present invention is diluted with water to an ultraviolet absorber concentration of 0.002% and the absorption spectrum is measured at room temperature using an ultraviolet-visible spectrophotometer (Shimadzu Corporation, UV-1850), the absorbance at 380 nm (A380) can be 0.50 to 0.75. Furthermore, when the ultraviolet absorber concentration in the ultraviolet absorber water dispersion composition is 0.002%, the ratio of the absorbance at 380 nm (A380) to the absorbance at 600 nm (A600) in the absorption spectrum is calculated, and A380 / A600 can be 200 or more, or even 250 or more, or 600 or more, or even 750. Furthermore, when the ultraviolet absorber concentration in the ultraviolet absorber water dispersion composition is 0.002%, the ratio of the absorbance at 400 nm (A400) to the absorbance at 600 nm (A600) in the absorption spectrum is calculated, and A400 / A600 can be 100 or more, or even 140 or more, or 190 or more, or even 200. High values ​​of A380 / A600 and A400 / A600 mean that the material can transmit sufficient visible light while absorbing sufficient ultraviolet light. If A380 / A600 is lower than 200 or A400 / A600 is lower than 100, it tends to become difficult to maintain high transparency while sufficiently blocking ultraviolet light. The relationship between wavelength and transmittance of an ultraviolet absorbent water-dispersion composition containing a specific compound used in the present invention is shown in Figure 9, and the relationship between wavelength and absorbance is shown in Figure 8. As can be seen from these figures, this ultraviolet absorbent water-dispersion composition has high transmittance in the visible region, excellent transparency, and maintains high transparency while sufficiently blocking ultraviolet light.

[0035] 2.Dispersed particle size In the water-dispersed composition, it is preferable to adjust the particle size of the ultraviolet absorber to fall within a certain range. Specifically, when the ultraviolet absorber concentration of the ultraviolet absorber aqueous dispersion composition of the present invention is diluted with water so that the loading index is in the range of 0.1 to 100, and the particle size is measured at room temperature using a particle size distribution analyzer (Microtrac UPA EX-150, manufactured by Nikkiso Co., Ltd.), the particle size is 10 to 35 nm, preferably 10 to 30 nm, and most preferably 13 to 20 nm. This range provides the best balance between the ultraviolet absorption performance and transparency described above. If the particle size is larger than 35 nm, transparency tends to decrease when attempting to obtain a transparent coating composition, whereas if the particle size is smaller than 10 nm, the liquid stability over time tends to decrease and the ultraviolet absorption performance tends to decrease.

[0036] 3.Viscosity The viscosity of the ultraviolet absorber aqueous dispersion composition, measured at 25°C using a viscometer (manufactured by Toki Sangyo Co., Ltd., product number "VISCOMETER TV-22"), is preferably 2.0 to 4.5 mPa·s, particularly preferably 2.0 to 3.0 mPa·s. This range is particularly preferable because it is easy to mix with other materials such as resin components and is easy to handle. By blending the above-mentioned components in the above-mentioned ratios, it is possible to easily adjust the viscosity to a preferred range.

[0037] 4. pH The pH of the ultraviolet absorber water dispersion composition can be appropriately selected depending on the purpose and the relationship with the pH of other components such as the resin to be blended. The pH can be appropriately adjusted by selecting the functional group of the surfactant.

[0038] The above-described ultraviolet absorber water dispersion composition can be further mixed with a resin component to form a paint, and in particular, can be made into an aqueous paint composition by using an aqueous dispersion medium. The aqueous coating composition of the present invention may be any aqueous composition capable of forming a coating on a substrate. Aqueous coating compositions include one-component types in which a curing agent containing a crosslinking agent coexists in the same system, and two-component types in which the base agent and curing agent are stored separately and mixed at the time of use. Either type can be used in the present invention. For example, the composition can be used for various purposes, such as those described in WO2015 / 152057. Coated articles using the ultraviolet absorber aqueous coating composition of the present invention have excellent weather resistance, maintain long-term performance, and show little increase in transmittance in the ultraviolet range and no decrease in transmittance in the visible range.

[0039] [Resin component] The UV absorber-containing aqueous coating composition of the present invention contains a resin component in addition to the UV absorber, dispersant and dispersion medium described above.The resin component is also not particularly limited, and various resins that have been used in aqueous coating compositions in the past can be used without limitation.For example, various water-soluble resins, emulsion resins, dispersion resins, etc. can be mentioned, and acrylic resins, urethane resins, acrylic urethane resins, styrene acrylic resins, silicone resins, fluororesins, etc. can be used without limitation. Commercially available products include BASF's Joncryl PDX-7630A (styrene-acrylic acid resin emulsion), Nippon Carbide's Nikazol RX-284SD (acrylic resin emulsion), Nippon Carbide Industries' Nikazol CL-101 (vinyl acetate emulsion), Nippon A&L's Smartex PA-9160 (SBR (styrene butadiene rubber) latex emulsion), Nippon A&L's Smartex PA-2327 (styrene-butadiene copolymer latex with continuous heterogeneous composition), Saiden Chemical's Saivinol EK-61 (emulsion-type acrylic resin), Showa Denko's Polysol AM-200 ((meth)acrylate copolymer emulsion), and Showa Denko's Polysol EVA. Examples of suitable emulsions include AD-5 (ethylene vinyl acetate emulsion), BR-700HN (acrylic emulsion) manufactured by Shin-Nakamura Chemical, Bonron S-1284 (acrylic (or styrene-acrylic) aqueous emulsion) manufactured by Mitsui Chemicals, Bonron S-415 (acrylic (or styrene-acrylic) aqueous emulsion) manufactured by Mitsui Chemicals, TOCRYL W-168 (acrylic emulsion) manufactured by Toyo Chem, and TOCRYL W-171 (acrylic emulsion) manufactured by Toyo Chem. Bonron S-415 (acrylic (or styrene-acrylic) aqueous emulsion) is preferred, and Joncryl PDX-7630A (styrene-acrylic resin emulsion) is the most preferred. According to the UV absorber-containing aqueous coating composition of the present invention, the UV absorber contained in the coating film formed has high performance, and therefore it is possible to reduce damage from sunlight or UV rays in the formed coating itself, in a substrate coated with the coating, and in a material that is exposed to sunlight or UV rays through the coated substrate (coated article).

[0040] The UV absorber-containing aqueous coating composition of the present invention can be suitably used as a coating material for various applications where UV absorption is desirable. The substrate to be coated is not limited, but examples include glass, resin glass, metal, plastic, fiber, cloth, paper, wood, concrete, etc. These substrates may be, for example, windowpane components, interior and exterior materials, building materials such as architectural structures, containers for food, medicine, cosmetics, chemicals, etc., signs, labels, solar cells, etc. Furthermore, by using the UV absorber-containing aqueous coating composition of the present invention as a substrate for printed matter, ink fading can be prevented. The UV absorber-containing aqueous coating composition of the present invention may be an ink, in which case, for example, ink fading can be prevented. The UV absorber-containing aqueous coating composition of the present invention may be an adhesive, in which case, for example, deterioration of the adhesive due to sunlight or UV rays can be prevented. Furthermore, the UV absorber-containing aqueous coating composition of the present invention can be coated on a substrate such as fiber to produce, for example, clothing, hats, umbrellas, etc., with UV-shielding properties. Furthermore, the aqueous coating composition containing the ultraviolet absorber of the present invention can be coated onto a food packaging film to produce a film that protects foodstuffs such as grains, vegetables, and fruits from ultraviolet rays. [Sol-gel coating composition] By incorporating the above-mentioned crystalline form of the present invention, it is possible to obtain a sol-gel coating composition of the present invention that has excellent performance, such as high transparency and a high UV-a blocking effect, when used in glass for automobiles or building materials. Although the method for producing the sol-gel coating composition of the present invention is not particularly limited, it is highly desirable to first produce an ultraviolet absorber water-dispersed composition containing at least an ultraviolet absorber, an aqueous medium, and a dispersant, and then add a resin component. It is particularly desirable to produce an ultraviolet absorber water-dispersed composition containing at least an ultraviolet absorber, an aqueous medium, a dispersant, and a surfactant, and then add a resin component. By dispersing the ultraviolet absorber to a preferred particle size at the stage of such an ultraviolet absorber water-dispersed composition, the resulting coating composition has excellent performance.

[0041] The present invention will now be described in more detail with reference to examples. Example

[0042] [Synthesis of 2,2'-methylenebis[6-(5-chloro-2H-benzotriazol-2-yl)-4-tert-octylphenol] and preparation of different crystal forms] The following examples are for illustrative purposes only and should not be construed as limiting the scope of the invention in any way.

[0043] <Method of producing intermediate 1> Intermediate 1: 6-chloro-2-[2-hydroxy-5-(1,1,3,3-tetramethylbutyl)phenyl]-2H-benzotriazole-1-oxide [1-1] A 300 mL flask was charged with 4-chloro-2-nitroaniline (31.4 g, 182 mmol), hydrochloric acid (36.0 wt%, 107 g, 1.06 mol), and water (78.8 g, 4.38 mol) and stirred to thoroughly disperse the mixture. While maintaining the temperature at 0-15°C, sodium nitrite (12.9 g, 187 mmol) was gradually added over 1 hour. After the addition, the mixture was maintained at 0-15°C for 2 hours, after which solid-liquid separation was performed to obtain a clear, yellow-orange diazonium salt solution. [1-2] Next, 4-tert-octylphenol (36.4 g, 176 mmol), sodium acetate (110 g, 1.34 mol), toluene (108 g, 1.17 mol), and water (157 g, 8.72 mol) were added to a 1000 mL flask and thoroughly dispersed by stirring. The entire diazonium salt solution obtained in [1-1] was gradually added over 1 hour while maintaining the temperature at 0 to 15°C. The resulting red azo compound was stored at 10 to 30°C until further use. [1-3] Sodium hydroxide (48.0 wt%, 42.0 g, 504 mmol) and hydroquinone (200 mg, 1.82 mmol) were added to the azo compound obtained in [1-2] above, and the temperature was adjusted to 40°C. To this, hydrazine (80.0 wt%, 11.4 g, 285 mmol) was gradually added over 1 hour while maintaining the temperature at 40-50°C. After the addition, the mixture was maintained at 70°C for 1 hour, and then the pH was adjusted to 6 with hydrochloric acid (36.0 wt%). The aqueous layer was removed by separation, and the organic layer was concentrated and diluted with 2-propanol (46.9 g, 780 mmol). The mixture was cooled to below 10°C and subjected to solid-liquid separation to obtain brown intermediate 1 (30.6 g, 81.8 mmol, 45.5% yield).

[0044] <Method for producing intermediate 2> Intermediate 2: 5-chloro-2-[2-hydroxy-5-(1,1,3,3-tetramethylbutyl)phenyl]-2H-benzotriazole [2-1] Intermediate 1 (30.6 g, 81.8 mmol), zinc powder (7.50 g, 115 mmol), water (75.0 g, 4.20 mol), and 4-methyl-2-pentanone (60.1 g, 600 mmol) were added to a 300 mL flask and thoroughly dispersed by stirring. While maintaining the temperature at 40-50°C, hydrochloric acid (36.0 wt%, 17.5 g, 173 mmol) was gradually added over 3 hours. After the addition, the mixture was held at 70°C for 1 hour, then separated at 90°C to remove the aqueous layer. The resulting organic layer was concentrated and diluted with 2-propanol (35.1 g, 585 mmol) and water (45.0 g, 2.50 mol). The mixture was cooled to below 10°C and subjected to solid-liquid separation to obtain brown intermediate 2 (25.8 g, 72.1 mmol, 88.1% yield).

[0045] <Method of producing the target compound> Target compound: 2,2'-methylenebis[6-(5-chloro-2H-benzotriazol-2-yl)-4-tert-octylphenol] Intermediate 2 (25.8 g, 72.1 mmol), dodecan-1-ol (59.2 g, 318 mmol), paraformaldehyde (92.0 wt%, 1.48 g, 45.3 mmol), diethylamine (2.69 g, 36.8 mmol), and potassium hydroxide (1.11 g, 19.8 mmol) were added to a 300 mL flask and thoroughly dispersed by stirring. The mixture was heated to 170-180 °C and maintained for 5 hours, after which the pH was adjusted to 5 with citric acid (8.02 g, 41.7 mmol). Methyl ethyl ketone (48.3 g, 670 mmol) was added to the mixture and thoroughly dispersed by stirring. Solid-liquid separation afforded the target compound (11.5 g, 15.8 mmol, 43.7% yield) as a whitish-brown solid.

[0046] <Production of Crystalline Form β> Intermediate 3 (6.50 g, 8.93 mmol), 4-methyl-2-pentanone (52.1 g, 520 mmol), and toluene (18.9 g, 205 mmol) were added to a 100 mL flask and dissolved by heating to 110°C. The solution was gradually cooled to precipitate crystals, and then concentrated by vacuum distillation while maintaining the precipitated crystals until the solvent was gone, yielding pale yellow-white crystalline form β (6.42 g, 8.82 mmol, 98.8% yield).

[0047] <Production of Crystalline Form α> Intermediate 3 (6.50 g, 8.93 mmol) and toluene (39.4 g, 428 mmol) were added to a 100 mL flask and heated to 110 °C to dissolve. The solution was gradually cooled to precipitate crystals, and then concentrated by vacuum distillation until the solvent was completely removed while maintaining the precipitated crystals. The resulting crystals were dispersed in 2-propanol (35.5 g, 591 mmol), followed by solid-liquid separation to obtain pale yellow-white crystalline form α (6.27 g, 8.61 mmol, 96.4% yield).

[0048] [Crystal structure identification] The obtained crystalline form β and crystalline form α were subjected to powder X-ray diffraction and single crystal X-ray structural analysis by the following methods.

[0049] 1. Powder X-ray Diffraction Powder (crystal) samples of the crystal forms β and α, which had been sieved through a 50 mesh, were packed tightly into a 0.5 mm capillary holder, and transmittance measurements were carried out under the following conditions.

[0050] Measurement equipment: Fully automatic multipurpose X-ray diffraction equipment SmartLab (manufactured by Rigaku) X-ray source: Cu Kα1 fine focus Tube voltage: 45kV Tube current: 200mA Measurement temperature: room temperature Scan axis: 2θ Scan range: 5°~40° Scan step: 0.01° Scan speed: 2° / min Measurement and analysis software: X-ray analysis integrated software SmartStudio II

[0051] The diffraction pattern of the obtained crystalline form β is shown in FIG. 1, and the diffraction pattern of the obtained crystalline form α is shown in FIG. The background of each data was corrected using a fitting method that removes the background by approximating it with a smooth curve.

[0052] 2. Single-crystal X-ray structure analysis A powder (crystal) sample of crystalline form β was placed on silicone grease on a hole slide glass, and one single crystal (0.014 x 0.012 x 0.004 mm) was selected from the powder sample, picked up together with the silicone grease using a MicroLoops LD 20 μmφ, and mounted. Then, measurements were carried out under the following conditions.

[0053] Measurement device: XtaLAB SynergyCustom FR-X (manufactured by Rigaku) X-ray source: CuKα (λ=1.54184Å) Tube voltage: 45kV Tube current: 66mA Measurement temperature: 100K Collimator diameter: 0.3 mm Camera length: 40mm Vibration angle: 0.5° Exposure time: 90 seconds per frame Total number of measurements: 790 Measurement time: 19 hours 46 minutes 56 seconds Data measurement and processing software: CrysAlis Pro Structural analysis program package: Olex2

[0054] The initial structure determination was performed using a direct method (SHELXT), and the structure refinement was performed using the full-matrix least-squares method (SHELXL). All non-hydrogen atoms were refined with anisotropic temperature factors. Hydrogen atoms were positioned appropriately using a riding model and given an isotropic temperature factor 1.2 times larger than that of the bonded non-hydrogen atoms. However, in the case of hydrogen atoms of methyl groups, they were positioned appropriately using a riding model and given an isotropic temperature factor 1.5 times larger than that of the bonded non-hydrogen atoms.

[0055] A powder (crystal) sample of crystalline form α was placed on silicone grease on a hole slide glass, and one single crystal (0.020 x 0.006 x 0.004 mm) was selected from the powder sample, picked up together with the silicone grease using a MicroLoops LD 20 μmφ, and mounted. Then, measurements were carried out under the following conditions.

[0056] Measurement device: XtaLAB SynergyCustom FR-X (manufactured by Rigaku) X-ray source: CuKα (λ=1.54184Å) Tube voltage: 45kV Tube current: 66mA Measurement temperature: 100K Collimator diameter: 0.3 mm Camera length: 40mm Vibration angle: 0.5° Exposure time: 90 seconds per frame Total number of measurements: 1462 Measurement time: 36 hours 37 minutes 35 seconds Data measurement and processing software: CrysAlis Pro Structural analysis program package: Olex2

[0057] The initial structure determination was performed using a direct method (SHELXT), and the structure refinement was performed using the full-matrix least-squares method (SHELXL). All non-hydrogen atoms were refined with anisotropic temperature factors. Hydrogen atoms were positioned appropriately using a riding model and given an isotropic temperature factor 1.2 times larger than that of the bonded non-hydrogen atoms. However, in the case of hydrogen atoms of methyl groups, they were positioned appropriately using a riding model and given an isotropic temperature factor 1.5 times larger than that of the bonded non-hydrogen atoms.

[0058] The crystallographic data of the crystalline forms β and α obtained by the above method are shown in Table 1.

[0059] [Table 1]

[0060] The ORTEP of crystalline form β obtained from the results of single crystal X-ray structural analysis is shown in Figure 3, and the ORTEP of crystalline form α is shown in Figure 4.

[0061] [Preparation of Water-Dispersed Composition] Example 1 10.0 parts by weight of crystalline form β of 2,2'-methylenebis[6-(5-chloro-2H-benzotriazol-2-yl)-4-tert-octylphenol] (DAINSORB TCL-43, manufactured by Daiwa Chemical Industry Co., Ltd.), 7.0 parts by weight of polyoxyethylene tribenzyl phenyl ether ("Emulgen B-66", manufactured by Kao Corporation, HLB 13.2) as a surfactant, 2.5 parts by weight of a polymer dispersant having an acid value (disperbyk-2015, manufactured by BYK-Chemie, acid value 10 mg KOH / g, active ingredient 40.0 wt%) as a dispersant, and 80.5 parts by weight of water were mixed and ground in a paint conditioner using φ0.1 mm zirconia beads for 10 hours to obtain an ultraviolet absorber aqueous dispersion composition 1. The average particle size of the obtained ultraviolet absorber water dispersion composition was measured at room temperature using a particle size distribution analyzer (Microtrac, manufactured by Nikkiso Co., Ltd.) and was found to be 16 nm (median diameter, D 50 ). The obtained ultraviolet absorber water dispersion composition was diluted with water so that the ultraviolet absorber concentration became 0.0982%, and the transmittance spectrum was measured at room temperature using an ultraviolet-visible spectrophotometer (Shimadzu Corporation, UV-1850). The transmittance at 600 nm was found to be 88.9%. The obtained ultraviolet absorber water dispersion composition was diluted with water so that the ultraviolet absorber concentration was 0.002%, and the absorption spectrum was measured at room temperature using an ultraviolet-visible spectrophotometer (Shimadzu Corporation, UV-1850). The absorbance at 380 nm was 0.728, the absorbance at 400 nm was 0.196, the A380 / A600 absorbance ratio was 728, and the A400 / A600 absorbance ratio was 196.

[0062] Comparative Example 1 The ultraviolet absorber was dispersed in the same manner as in Example 1, except that the ultraviolet absorber was changed to crystalline form α of 2,2'-methylenebis[6-(5-chloro-2H-benzotriazol-2-yl)-4-tert-octylphenol] (DAINSORB TCL-43, manufactured by Yamato Chemical Industry Co., Ltd.). The average particle size, transmittance, absorbance, A380 / A600 absorbance ratio, and A400 / A600 absorbance ratio of the obtained ultraviolet absorbent water dispersion composition were measured in the same manner as in Example 1, and were found to be 22 nm in average particle size, 88.8% in transmittance, 0.618 in absorbance at 380 nm, 0.143 in absorbance at 400 nm, 618 in A380 / A600 absorbance ratio, and 143 in A400 / A600 absorbance ratio.

[0063] Comparative Example 2 An ultraviolet absorber was dispersed in the same manner as in Example 1, except that the ultraviolet absorber was changed to 2,2'-methylenebis[6-(2H-benzotriazol-2-yl)-4-tert-octylphenol] (Tinuvin 360 manufactured by BASF). The average particle size, transmittance, absorbance, A380 / A600 absorbance ratio, and A400 / A600 absorbance ratio of the obtained ultraviolet absorbent water dispersion composition were measured in the same manner as in Example 1, and were found to be 24 nm in average particle size, 87.9% in transmittance, 0.547 at 380 nm in absorbance, 0.029 at 400 nm in absorbance, 547 in A380 / A600 absorbance ratio, and 29 in A400 / A600 absorbance ratio.

[0064] Comparative Example 3 An ultraviolet absorber was dispersed in the same manner as in Example 1, except that the ultraviolet absorber was changed to 2-(5-chloro-2H-benzotriazol-2-yl)-6-tert-butyl-4-methylphenol (Tinuvin 326 manufactured by BASF). The average particle size, transmittance, absorbance, A380 / A600 absorbance ratio, and A400 / A600 absorbance ratio of the obtained ultraviolet absorbent water dispersion composition were measured in the same manner as in Example 1, and were found to be an average particle size of 119 nm, a transmittance of 1.9%, an absorbance at 380 nm of 0.962, an absorbance at 400 nm of 0.546, an A380 / A600 absorbance ratio of 27, and an A400 / A600 absorbance ratio of 16.

[0065] Comparative Example 4 The ultraviolet absorber was dispersed in the same manner as in Example 1, except that the ultraviolet absorber was changed to 2,2'-(1,4-phenylene)bis[4H-3,1-benzoxazin-4-one] (KEMISORB500 manufactured by Chemipro Chemicals). The average particle size, transmittance, absorbance, A380 / A600 absorbance ratio, and A400 / A600 absorbance ratio of the obtained ultraviolet absorbent water dispersion composition were measured in the same manner as in Example 1, and were found to be an average particle size of 81 nm, a transmittance of 1.7%, an absorbance at 380 nm of 0.920, an absorbance at 400 nm of 0.798, an A380 / A600 absorbance ratio of 25, and an A400 / A600 absorbance ratio of 22.

[0066] Table 2 shows the average particle size, transmittance, absorbance, A380 / A600 absorbance ratio and A400 / A600 absorbance ratio of each of the obtained ultraviolet absorbent water dispersion compositions.

[0067] [Table 2]

[0068] From the above, it can be seen that the transmittance, absorbance, A380 / A600 absorbance ratio, and A400 / 600 absorbance ratio of the crystalline β water-dispersed composition are higher than those of the comparative water-dispersed compositions, and therefore the water-dispersed composition has ultraviolet blocking performance that can block UV-a rays in the longer wavelength range while maintaining high transparency. [Industrial Applicability]

[0069] According to the present invention, it is possible to obtain an ultraviolet absorbing compound having a novel crystalline form and capable of improving ultraviolet shielding performance while maintaining high transparency, and an aqueous water dispersion composition and a sol-gel coating composition containing the same.

Claims

1. A crystalline form of a compound represented by the following chemical formula (I), characterized in that it exhibits a powder X-ray diffraction pattern having peaks at 2θ angles of 8.6° (±0.2°), 12.4° (±0.2°), 14.4° (±0.2°), 15.2° (±0.2°), 16.1° (±0.2°), 24.5° (±0.2°), 26.7° (±0.2°), 31.0° (±0.2°), and 33.7° (±0.2°), and no peak at 10.1° (±0.2°). (In chemical formula (I), R represents a halogen atom, and R′ represents an alkyl group having 4 to 12 carbon atoms, which may be branched or may have a substituent.) Chemical formula (I) 【Chemistry 1】

2. A crystalline form of the compound represented by the following general formula (II), characterized by exhibiting a powder X-ray diffraction pattern having peaks at 2θ angles of 8.6° (±0.2°), 12.4° (±0.2°), 14.4° (±0.2°), 15.2° (±0.2°), 16.1° (±0.2°), 24.5° (±0.2°), 26.7° (±0.2°), 31.0° (±0.2°), and 33.7° (±0.2°), and no peak at 10.1° (±0.2°). Chemical formula (II) 【Chemistry 2】 (R １ , R １ ', R ２ and R ２ ' is one of the following (i) to (iv): (i) R １ and R １ ' is a chlorine atom and R ２ and R ２ ' is a hydrogen atom, (ii) R １ and R １ ' is a hydrogen atom and R ２ and R ２ ' is a chlorine atom, (iii) R １ and R 2 ' is a chlorine atom and R ２ and R 1 ' is a hydrogen atom, (iv) R １ and R 2 ' is a hydrogen atom and R ２ and R 1 ' is a chlorine atom.)

3. The crystalline form of claim 1, characterized in that the peak magnitudes are: the peak at 8.6° (±0.2°) > the peak at 12.4° (±0.2°), the peak at 8.6° (±0.2°) > the peak at 24.5° (±0.2°), and the peak at 14.4° (±0.2°) < the peak at 24.5° (±0.2°).

4. The crystalline form of claim 2, characterized in that the peak magnitudes are: the peak at 8.6° (±0.2°) > the peak at 12.4° (±0.2°), the peak at 8.6° (±0.2°) > the peak at 24.5° (±0.2°), and the peak at 14.4° (±0.2°) < the peak at 24.5° (±0.2°).

5. A crystalline form of a compound represented by the following general formula (II), characterized in that it contains 50% or more of the compound (ii). Chemical formula (II) 【Transformation 3】 (R １ , R １ ', R ２ and R ２ ' is one of the following (i) to (iv): (i) R １ and R １ ' is a chlorine atom and R ２ and R ２ ' is a hydrogen atom, (ii) R １ and R １ ' is a hydrogen atom and R ２ and R ２ ' is a chlorine atom, (iii) R １ and R 2 ' is a chlorine atom and R ２ and R 1 ' is a hydrogen atom, (iv) R １ and R 2 ' is a hydrogen atom and R ２ and R 1 ' is a chlorine atom.)

6. A crystalline form consisting of a compound represented by the following chemical formula (I), characterized in that the crystalline form is an orthorhombic crystal system, a space group Pbcn, and has lattice constants a: 19.0217(13), b: 8.0822(6), and c: 24.494(4). (In chemical formula (I), R represents a halogen atom, and R′ represents an alkyl group having 4 to 12 carbon atoms, which may be branched or may have a substituent.) Chemical formula (I) 【Chemistry 4】

7. A water-dispersed composition comprising the crystalline form according to any one of claims 1 to 6 dispersed in an aqueous medium.

8. 7. A water-dispersed composition of an ultraviolet absorber in an aqueous medium, wherein the ultraviolet absorber contains the crystalline form according to any one of claims 1 to 6.

9. 9. The ultraviolet absorber water dispersion composition according to claim 8, wherein the ultraviolet absorber dispersed in the aqueous medium has a dispersed particle size of 10 to 35 nm.

10. A sol-gel coating composition comprising the crystalline form according to any one of claims 1 to 6.

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