TW202346404A - Curable resin composition - Google Patents

Abstract

To provide a curable resin composition for black light shielding for an inkjet, the curable resin composition having excellent surface curability in addition to high light-shielding properties, exhibiting stable adhesion under high-temperature and high-humidity conditions, and yielding a cured coating film having high hardness after curing. A curable resin composition containing (A) an epoxy compound, (B) an oxetane compound, (C) a photoacid generator, and (D) a black colorant, wherein the (A) epoxy compound contains (a) an alicyclic epoxy compound having an ester bond in each molecule and (b) an alicyclic epoxy compound not having an ester bond in each molecule in a mass ratio within a numerical range of 5:100-30:100.

Description

Hardening resin composition

The present invention relates to a curable resin composition.

Since the light-shielding member installed in a display of a PC or a mobile device needs to reduce the influence of backlight as much as possible, high light-shielding properties are required. Therefore, as a material of such a light-shielding member, light-shielding ink for forming a black matrix is used. On the other hand, from the viewpoint of manufacturing efficiency, a technology for manufacturing a light-shielding member by applying such light-shielding ink to a substrate using an inkjet method has attracted attention. As a technology for applying ink to an object using an inkjet method, for example, Patent Document 1 proposes an active agent including a photocationic polymerization initiator, a polyfunctional epoxy compound, a monofunctional alicyclic epoxy compound, and an oxycyclobutane compound. Energy ray hardening ink is a technology used in inkjet recording. [Prior technical literature] [Patent Document]

[Patent Document 1] Japanese Patent Application Publication No. 2010-106254

[Problem to be solved by the invention]

Here, in particular, smartphones and smart watches are naturally expected to be used in various environments such as summer and inside cars, in addition to being used at normal temperatures. Therefore, it is expected that the light-shielding ink used has high reliability. For example, in addition to high light-shielding properties, light-shielding inks also need to maintain high adhesion to the base material even under high temperatures and high humidity, have good curability, and have high hardness in the cured coating film formed after curing.

However, in general, light-shielding inks are added with high concentrations of pigments for light-shielding purposes, resulting in a high OD value. Therefore, if an attempt is made to apply light-shielding ink to a base material using an inkjet method, it is inevitable that light used to photoharden the light-shielding ink coating film formed on the base material will be difficult to reach the bottom of the coating film. As a result, the curability of the entire coating film is insufficient, and the problem arises that the hardness of the cured coating film itself and the adhesion to a base material such as glass or metal are reduced.

In this regard, in the active energy ray-curable ink proposed in Patent Document 1, although an alicyclic epoxy compound having an ester bond in the molecule is used, when the pigment concentration is increased, it is estimated that it is difficult for light to sufficiently reach the coating film. bottom. Therefore, the curing properties of the coating film are insufficient, and it is difficult to maintain the adhesion of the cured coating film to the base material when left under high temperature and high humidity conditions, and the hardness of the cured coating film after curing of the ink is not satisfactory. required level.

Therefore, in view of the above viewpoints, an object of the present invention is to provide a curable resin composition that not only has high light-shielding properties but also has good surface hardening properties and exhibits stable adhesion under high-temperature and high-humidity conditions while curing. The final hardness of the hardened coating is also high. [Means to solve the problem]

As a result of diligent research, the inventors of the present invention found that by using a mass ratio within a specific numerical range, two types of epoxy compounds having respective structural characteristics are included, and further, an oxycyclobutane compound, a photoacid generator, and a black colorant are included. In order to solve the above-mentioned problems using a curable resin composition, the present invention was completed. That is, this problem is solved more specifically as follows. A curable resin composition comprising (A) an epoxy compound, (B) an oxybutane compound, (C) a photoacid generator, and (D) a black colorant, The aforementioned (A) epoxy compound includes (a) an alicyclic epoxy compound with an ester bond in the molecule and (b) an alicyclic epoxy compound that does not have an ester in the molecule at a mass ratio in the numerical range of 5:100 to 30:100. Bonded alicyclic epoxy compounds.

The curable resin composition of the present invention can be suitably used in the inkjet method. In this case, a more preferable aspect is that from the viewpoint of smooth ejection from the inkjet nozzle, the viscosity is preferably in the range of 5 to 20 mPa･s at 50°C, and further preferably 5 at 50°C. ~15mPa･s range. The viscosity can be measured using, for example, a cone plate viscometer (TVE-33H manufactured by Toki Sangyo Co., Ltd.).

A more preferred aspect relates to a curable resin composition in which the alicyclic epoxy compound (b) having no ester bond in the molecule has a bifunctional epoxy group.

Another preferred aspect relates to the curable resin composition, wherein the aforementioned (D) black colorant is carbon black, and relative to the total of the aforementioned (A) epoxy compound and (B) oxycyclobutane compound 100 Parts by mass include more than 5 parts by mass.

Another preferred aspect relates to the curable resin composition, wherein the mass ratio of the aforementioned (B) oxycyclobutane compound and the aforementioned (A) epoxy compound is in the range of 2:100 to 40:100.

Another preferred aspect relates to a curable resin composition, wherein the aforementioned (A) epoxy compound contains (a) an epoxy compound having an ester bond in the molecule at a mass ratio in the range of 8:100 to 25:100. an alicyclic epoxy compound, and (b) an alicyclic epoxy compound that does not have an ester bond within the molecule. By setting the ratio of the blending amount of (a) the alicyclic epoxy compound having an ester bond in the molecule to the above range, a cured coating film with excellent adhesion can be produced even after being left under high temperature and high humidity conditions. . By setting the blending amount of (a) the alicyclic epoxy compound having an ester bond in the molecule to be more than the lower limit of the above-mentioned mass ratio, it is assumed that the flexibility of the coating film can be appropriately maintained through hydrolysis of the ester bond, Suppresses the internal stress of the coating film and improves initial adhesion. Furthermore, by setting the blending amount of (a) the alicyclic epoxy compound having an ester bond in the molecule to be less than the upper limit of the above-mentioned mass ratio, it is expected to suppress the hydrolysis of the coating film caused by being left under high temperature and high humidity conditions. It can prevent the deterioration of the coating film and maintain the physical properties of the coating film after photocuring such as adhesion.

Another preferred aspect relates to the curable resin composition, wherein the mass ratio of the aforementioned (B) oxycyclobutane compound and the aforementioned (A) epoxy compound is in the range of 10:100 to 20:100. By setting the ratio of the blending amount of the (B) oxybutane compound within the above range, the curability of the surface and bottom of the coating film can be improved in a balanced manner. By setting the ratio of the above-described blending amount to be equal to or higher than the lower limit, the tackiness of the cured coating film after photocuring becomes good. Furthermore, by setting the ratio of the above-mentioned blending amount to less than the upper limit, the cross-linking density of the cured coating film can be appropriately maintained, the flexibility can be maintained, and the pencil hardness and adhesion after being left under high-temperature and high-humidity conditions can be improved.

Another preferred aspect also relates to a curable resin composition, which further contains an alkoxyanthracene derivative as a photosensitizer.

Since the curable resin composition of the present invention is suitable for use as a black light-blocking agent for smartphones and the like, a more preferable aspect is that the OD value of the cured coating film when the film thickness is 10 to 20 μm is preferably 4 or more, and more preferably Preferably it is 5 or more. The OD value can be calculated based on the formula OD value = -log10 (T/100) by measuring the amount of transmitted light using, for example, a transmission density meter (model: [Effects of the invention]

The curable resin composition of the present invention having the above-described structure has the ability to form a cured product that not only has high light-shielding properties, but also has good curability on the surface of the coating film, exhibits stable adhesion even under high temperature and high humidity conditions, and has high hardness. Advantages of coating. Moreover, since the curable resin composition of the present invention is also suitable for inkjet applications, it also has the advantage of good manufacturing efficiency in the production of various displays. Furthermore, due to the above-described characteristics, the curable resin composition of the present invention is expected to be particularly suitable for use as a black light-shielding material for displays, for example.

[(A) Epoxy compound]

The curable resin composition of the present invention contains (A) an epoxy compound in order to increase the hardness of the formed cured product (cured coating film). In particular, the curable resin composition of the present invention uses (a) as the above-mentioned (A) epoxy compound in order to improve the adhesion to the base material even when exposed to a harsh environment of higher temperature and high humidity. Two types of epoxy compounds: an alicyclic epoxy compound having an ester bond in the molecule, and (b) an alicyclic epoxy compound having no ester bond in the molecule.

When an epoxy compound is used as a curable resin composition with a high OD value, an alicyclic epoxy compound among epoxy compounds is usually used as one of the components due to its high reactivity. In particular, it is customary to use an alicyclic epoxy compound having an ester bond from the viewpoint of improving surface curability or curability during use of the curable resin composition. However, even a curable resin composition containing an alicyclic epoxy compound having such an ester bond has problems when used in displays for smartphones and the like that are exposed to harsh environments such as higher temperatures and high humidity. The disadvantage of insufficient adhesion to the substrate.

Therefore, in the present invention, two kinds of epoxy compounds (a) an alicyclic epoxy compound having an ester bond in the molecule and (b) an alicyclic epoxy compound having no ester bond in the molecule are used together as (A) Epoxy compounds, and not only that, by including these two epoxy compounds in the curable resin composition at a mass ratio in the range of 5:100 to 30:100, preferably 8:100 to 25:100 , can seek to avoid the above-mentioned shortcomings. By setting the ratio of the blending amount of (a) the alicyclic epoxy compound having an ester bond in the molecule to the above range, the influence of deterioration of the coating film after photocuring due to the hydrolysis of the ester can be suppressed, and It combines the flexibility and hardening properties of the coating film and exhibits excellent adhesion.

Hereinafter, the use of (a) an alicyclic epoxy compound having an ester bond in the molecule and (b) the epoxy compound contained in the (A) epoxy compound as a component of the curable resin composition of the present invention will be described. Alicyclic epoxy compounds without ester bonds.

[(a) Alicyclic epoxy compound with ester bond in the molecule] In the present invention, an alicyclic epoxy compound refers to a compound having one or more aliphatic ring structures in the molecule, and two carbon atoms in the aliphatic ring and oxygen atoms further form a ring to form an epoxy group. Furthermore, (a) the alicyclic epoxy compound having an ester bond in the molecule refers to a compound in which the aforementioned alicyclic epoxy compound further has an ester bond in its chemical structure.

Preferable examples of the alicyclic epoxy compound having an ester bond in the molecule (a) include, for example, compounds having the following structures: (In the formula, n1 represents an integer from 1 to 30) (In the formula, A represents an alkylene group with 1 to 8 carbon atoms; n2 represents an integer from 1 to 30)

As (a) the alicyclic epoxy compound having an ester bond in the molecule, commercially available products can of course be used, and preferred examples include CELLOXIDE 2021P or CELLOXIDE 2081 (either manufactured by Daicel).

(a) The alicyclic epoxy compound having an ester bond in the molecule may be used alone or in combination of two or more.

[(b) Alicyclic epoxy compound not having an ester bond in the molecule] In the present invention, (b) an alicyclic epoxy compound not having an ester bond in the molecule means the above (a) having an ester bond in the molecule The alicyclic epoxy compound described in the item of the bonded alicyclic epoxy compound is a compound that does not have an ester bond in the molecule, such as an alicyclic epoxy compound that has an ether bond in place of an ester bond. Examples of (b) alicyclic epoxy compounds that do not have an ester bond in the molecule include compounds having the following structures:

As (b) the alicyclic epoxy compound that does not have an ester bond in the molecule, commercially available products can of course be used, and preferred examples include limonene dioxide (LDO) (manufactured by SYMRISE Co., Ltd.), THI-DE , DE-102 and DE-103 (manufactured by JXTG Energy Co., Ltd.), X-40-2678 and X-40-2669 (manufactured by Shin-Etsu Chemical Industry Co., Ltd.), EHPE-3150 and CELLOXIDE 2000 (manufactured by Daicel Co., Ltd.), and KR-470 (manufactured by Shin-Etsu Chemical Co., Ltd.), etc.

Furthermore, among the alicyclic epoxy compounds (b) that do not have an ester bond in the molecule, those having a bifunctional epoxy group are preferred in the present invention. The alicyclic bifunctional epoxy compound (b) which does not have an ester bond in the molecule has an oxirane group represented by the following structural formula in the molecule: And/or the epoxycyclohexyl group represented by the following structural formula: A total of 2 compounds. Examples of commercially available products include THI-DE, DE-102 and DE-103 (manufactured by JXTG Energy Co., Ltd.), X-40-2678 and X-40-2669 (manufactured by Shin-Etsu Chemical Industry Co., Ltd.), and the like.

(b) An alicyclic epoxy compound that does not have an ester bond in the molecule may be used alone or in combination of two or more.

The total content of (a) an alicyclic epoxy compound having an ester bond in the molecule in the curable resin composition of the present invention is smaller than that of (A) epoxy compound from the viewpoint of curability and tackiness. The total amount of the compound and the (B) oxybutane compound is 100 parts by mass, preferably 3 to 60 parts by mass, and more preferably 3 to 30 parts by mass. Furthermore, the total content of (b) an alicyclic epoxy compound that does not have an ester bond in the molecule is smaller than that of the (A) epoxy compound and (B) from the viewpoint of adhesion to the base material. The total amount of 100 parts by mass of the oxybutane compound is preferably 30 to 90 parts by mass, and more preferably 40 to 80 parts by mass. However, the respective contents of the two alicyclic epoxy compounds (a) and (b) need to be adjusted to a ratio within the specific numerical range mentioned above.

[Other epoxy compounds] In addition to the above-mentioned (a) alicyclic epoxy compound having an ester bond in the molecule and (b) an alicyclic epoxy compound having no ester bond in the molecule, the curable resin composition of the present invention further improves the For the purpose of improving the characteristics of the curable resin composition of the present invention, or for the purpose of imparting new characteristics, the (A) epoxy compound can of course further include epoxy compounds other than (a) and (b), such as non-alicyclic compounds. Formula epoxy compounds, etc. as other epoxy compounds. Since conventional epoxy compounds that can be used in the present invention are sufficient, they cannot be listed in full here. If preferred ones are specifically listed, for example, Denacol EX-212 and Denacol EX-121 (either Both are manufactured by Denacol Co., Ltd.), and KBM-403 (manufactured by Shin-Etsu Silicone Co., Ltd.). The total content when such other epoxy compounds are contained, relative to (A) epoxy compounds (including the epoxy compounds of (a) and (b) and other epoxy compounds) and (B) oxygen The total amount of the cyclobutane compound is 100 parts by mass, preferably 130 parts by mass, and more preferably 3 to 20 parts by mass.

[(B) Oxybutane compound] The curable resin composition of the present invention contains (B) an oxybutane compound as a thermosetting resin from the viewpoint of improving the hardness of the cured product. However, in the present invention, the content of the (B) oxycyclobutane compound can be adjusted relative to the total amount of the above-mentioned (A) epoxy compound, that is, (a) an alicyclic ring having an ester bond in the molecule The total amount of the oxygen compound, (b) the alicyclic epoxy compound that does not have an ester bond in the molecule, and other epoxy compounds becomes a mass ratio within a specific numerical range. Specifically, the content of the (B) oxybutane compound can be adjusted so that the mass ratio of the (B) oxybutane compound to the (A) epoxy compound becomes a numerical range of 2:100~40:100, which is relatively The best value range is 10:100~20:100.

The oxybutane compound (B) is not limited to a monofunctional compound, and a polyfunctional compound can also be used. Examples of the monofunctional (B) oxybutane compound include 3-methyloxybutane, 3-ethyloxybutane, 3-hydroxymethyloxybutane, and 3-methyl- 3-hydroxymethyloxycyclobutane, 3-ethyl-3-hydroxymethyloxycyclobutane, etc.

Examples of the polyfunctional (B) oxybutane compound include bis[(3-methyl-3-oxetanylmethoxy)methyl]ether, bis[(3-ethyl- 3-Oxobutanylmethoxy)methyl]ether, 1,4-bis[(3-methyl-3-oxobutanylmethoxy)methyl]benzene, 1,4-bis[ (3-ethyl-3-oxobutanylmethoxy)methyl]benzene, (3-methyl-3-oxobutanyl)methyl acrylate, (3-ethyl-3-oxoacrylate Cyclobutyl) methyl ester, (3-methyl-3-oxocyclobutanyl) methyl methacrylate, (3-ethyl-3-oxocyclobutanyl) methyl methacrylate, etc. In addition to polyfunctional oxycyclobutanes such as oligomers or copolymers, oxycyclobutanol and phenolic resins, poly(p-hydroxystyrene), Cardo-type bisphenols, and calixarenes , resorcinol calixarenes, or etherates with resins having hydroxyl groups such as sesquioxane, etc. Other examples include copolymers of an unsaturated monomer having an oxybutane ring and an alkyl (meth)acrylate.

Of course, a commercially available product can be used as (B) an oxybutane compound. For example, OXT-101, OXT-121, OXT-212, and OXT-221 (manufactured by Toagosei Co., Ltd.) are preferred.

The curable resin composition of the present invention may contain one type alone or two or more types of the above-mentioned (B) oxybutane compounds.

From the viewpoint of the hardness of the cured product, the content of the (B) oxybutane compound is preferably 100 parts by mass in total of the (A) epoxy compound and (B) the oxybutane compound. The amount is 3 to 40 parts by mass, and more preferably 8 to 30 parts by mass. However, the content of the (B) oxybutane compound needs to be adjusted so that the mass ratio to the mass of the contained (A) epoxy compound falls within the specific numerical range as described above. The total blending amount of (A) the epoxy compound and (B) the oxybutane compound is preferably 25 to 95 mass % based on the mass of the curable resin composition of the present invention, and further preferably 35 ~90% by mass.

[(C) Photoacid generator] The curable resin composition of the present invention contains (C) a photoacid generator as a compound capable of generating a substance that initiates cationic polymerization by ultraviolet irradiation. (C) Photoacid generators include, for example, diazonium salts, iodonium salts, bromium salts, chlorium salts, sulfonium salts, selenium salts, pyranium salts, thiopyranium salts, and pyridinium salts. Onium salts such as salts; halogenated compounds such as (trihalomethyl)-s-triazine and its derivatives; 2-nitrobenzyl ester of sulfonic acid; iminosulfonate ester; 1-side oxy- 2-naphthoquinone diazonium-4-sulfonate derivatives; N-hydroxyiminosulfonate; tris(methanesulfonyloxy)benzene derivatives; disulfonyldiazomethanes; sulfonyl Carbonyl alkanes; sulfonyl carbonyl diazomethanes; distilone compounds, etc. Such (C) photoacid generators may be used alone or in combination of two or more types.

As the (C) photoacid generator, commercially available products can be used, and examples include CPI-100P, CPI-200K, CPI-101A (above, manufactured by San-Apro Co., Ltd.), CYRACURE photohardening initiator UVI-6990, CYRACURE photo Hardening initiator UVI-6992, CYRACURE light hardening initiator UVI-6976 (above, manufactured by Dow Chemical Japan Co., Ltd.), ADEKA OPTOMER SP-150, ADEKA OPTOMER SP-152, ADEKA OPTOMER SP-170, ADEKA OPTOMER SP- 172 (above, manufactured by Asahi Den Chemical Co., Ltd.), CI-5102, CI-2855 (above, manufactured by Nippon Soda Corporation), San-Aid SI-60L, San-Aid SI-80L, San-Aid SI-100L, San- Aid SI-110L, San-Aid SI-180L, San-Aid SI-110, San-Aid SI-145, San-Aid SI-150, San-Aid SI-160, San-Aid SI-180 (above, three New Chemical Industry Co., Ltd.), ESACURE 1064, ESACURE 1187 (above, made by LAMBERTI Co., Ltd.), Omnicat 432, Omnicat 440, Omnicat 445, Omnicat 550, Omnicat 650, Omnicat BL-550, Omnicat 250 (made by IGM Resin Co., Ltd.), RHODORSIL PHOTOINITIATOR 2074 (manufactured by Rhodia Japan), WPI-113, WPI-116, WPI-169, WPI-170 (manufactured by Wako Pure Chemical Industries, Ltd.), etc.

Among these, CPI-100P, CPI-101A, CPI-200K, CPI-210S, or Omnicat 250, WPI-113, WPI-116, WPI-169 and WPI-170 of aromatic iodonium salts are preferred.

The content of (C) photoacid generator in the curable resin composition is preferably 5 to 30 parts by mass relative to 100 parts by mass of the total of (A) epoxy compound and (B) oxybutane compound. Preferably it is 7~15 parts by mass.

[(D) Black colorant] The curable resin composition of the present invention preferably contains (D) a black colorant, particularly a black pigment, from the viewpoint of generally being used as a black light-shielding agent. Typically, it is preferable to use black pigments such as carbon black, but black dyes and colorants with other colors may be used as long as they do not greatly exceed the intended use. Of course, they may be additionally included in addition to carbon black.

Examples of black pigments include, in addition to carbon black, inorganic pigments such as ferric oxide (Fe ₃ O ₄ ), black titanium oxide, copper manganese black, copper chrome black, and cobalt black, and organic pigments such as cyanine black and aniline black. Pigments.

Examples of colorants having other colors include well-known and commonly used red, blue, green, and yellow pigments or dyes.

The content of (D) black colorant in the curable resin composition of the present invention is adjusted taking into account the use of the cured product to be formed. From the perspective of the balance between the curability and adhesion of the coating film, relative to (A ) The total of 100 parts by mass of the epoxy compound and (B) the oxybutane compound preferably contains 5 parts by mass or more, and further preferably contains 5 parts by mass or more and 15 parts by mass or less.

[Photosensitizer] In order to further improve the photosensitivity, the curable resin composition of the present invention preferably further contains a photosensitizer. The photosensitizer is preferably a compound that enters an excited state by light with a wavelength of 350 nm to 450 nm. Examples include polynuclear aromatics such as pyrene, perylene, triphenylene, and anthracene; and oxera such as fluorescein, eosin, erythrosine, rhodamine B, and rose Bengal. Anthracenes (xanthenes); Cyanines such as oxacarbocyanine; merocyanines, carbomerocyanine and other merocyanines; rhodacyanines; oxonols; thiocyanidins (thionin), methylene blue, toluidine blue and other thiazides; acridines (acridines) such as acridine orange, chloroflavin, acriflavine (acriflavine); acridone, 10-butyl-2- Acriridones such as chloroacridone; anthraquinones; squaryliums; styrenes; basic styrenes; coumarins such as 7-diethylamino 4-methylcoumarin class. Among these, anthracene compounds, especially alkoxyanthracene derivatives, are preferred. Of course, two or more of these photosensitizers can be used in combination.

As the photosensitizer, commercially available products can also be used. Preferable examples of this include ANTHRACURE (registered trademark) UVS-1101 (diethoxyanthracene; manufactured by Kawasaki Chemical Industry Co., Ltd.), ANTHRACURE (registered trademark) UVS-1221 (dipropoxyanthracene; Kawasaki Chemical) Co., Ltd.), ANTHRACURE (registered trademark) UVS-1331 (dibutoxyanthracene; Kawasaki Chemical Co., Ltd.) and other alkoxyanthracene derivatives.

The content of the photosensitizer is 0.1 to 2.0 parts by mass, preferably 0.2 to 1.0 parts by mass relative to 1 part by mass of the photoacid generator.

[Other ingredients] Furthermore, the curable resin composition of the present invention may further contain solvents, reactive diluents, dispersants, tackifiers, surfactants, antioxidants, plasticizers, flame retardants, etc. within the scope that does not impair its characteristics. agents, antistatic agents, leveling agents, defoaming agents and antibacterial agents and other ingredients. As the reactive diluent capable of reducing the viscosity of the curable resin composition of the present invention, a photoreactive diluent is preferred. Examples of the photoreactive diluent include (meth)acrylates, vinyl ethers, ethylene derivatives, styrene, chloromethylstyrene, α-methylstyrene, maleic anhydride, and dicyclopentadiene. , N-vinylpyrrolidone, N-vinylformamide, xylylenedioxycyclobutane, oxycyclobutanol, 3-ethyl-3-(phenoxymethyl)oxycyclobutane , resorcinol diglycidyl ether and other compounds with unsaturated double bonds, oxycyclobutanyl groups, and epoxy groups. Among these, (meth)acrylates are preferred.

[Hardened material and its manufacturing method] The curable resin composition of the present invention is applied to a target position on a substrate by an inkjet method, and then cured to form a cured product. The inkjet printing method is preferably an on-demand piezoelectric method, but is not particularly limited. Suitable wavelengths include 365 nm, 385 nm, 395 nm, 405 nm, etc. in the ultraviolet region, but are not particularly limited. Hardening can be performed on the applied composition by irradiation of active energy rays. As the irradiation light source of active energy rays, LED, low-pressure mercury lamp, medium-pressure mercury lamp, high-pressure mercury lamp, ultra-high-pressure mercury lamp, xenon lamp, metal halide lamp, etc. are suitable. Other electron beams, α rays, β rays, γ rays, X rays, neutron beams, etc. can also be used. Furthermore, the number of irradiation light sources is one or two or more. In the case of two or more, it is of course possible to use light sources with different wavelengths in combination.

Furthermore, the exposure amount by active energy rays is usually 10~10000mJ/ ^cm2 , preferably 20~2000mJ/ ^cm2 , and further preferably within the range of 100~2000mJ/ ^cm2 .

Hereinafter, the present invention will be described in detail using Examples and Comparative Examples. However, the present invention is not limited to the following Examples. In addition, unless otherwise stated, the "parts" and "%" shown are based on mass. [Example]

Each component was blended separately according to the blending amount described in Table 1 below, and preliminarily mixed in a mixer to prepare curable resin compositions of Examples 1 to 10 and Comparative Examples 1 to 4. In addition, the numerical values of the blending amounts in the tables represent parts by mass unless otherwise specified.

※The ingredients corresponding to each number in Table 1 are as follows. 1) (a) Alicyclic epoxy compound with an ester bond in the molecule: CELLOXIDE 2021P (manufactured by Daicel) Chemical name: 3,4-epoxycyclohexylmethyl (3,4-epoxy)cyclohexane Carboxylic acid ester 2) (a) Alicyclic epoxy compound with an ester bond in the molecule: CELLOXIDE 2081 (manufactured by Daicel) Chemical name: ε-caprolactone modified 3,4-epoxycyclohexylmethyl 3 ',4'-Epoxycyclohexanecarboxylate 3) (b) Alicyclic epoxy compound without ester bond in the molecule: LDO (manufactured by SYMRISE Co., Ltd.) Chemical name: limonene dioxide 4) (b) Alicyclic epoxy compounds without ester bonds in the molecule: THI-DE (manufactured by JXTG Energy Co., Ltd.) Chemical name: tetrahydroindene diepoxide 5) Other epoxy compounds: Denacol EX-212 (manufactured by Nagase ChemteX Co., Ltd.) Chemical name: 1,6-hexanediol diglycidyl ether 6) Other epoxy compounds: Denacol EX-121 (manufactured by Nagase ChemteX Co., Ltd.) Chemical name: 2-ethyl ether Hexylglycidyl ether 7) Other epoxy compounds: KBM-403 (manufactured by Shin-Etsu Chemical Co., Ltd.) is a silane coupling agent with an epoxy group as an organic functional group, chemical name: 3-glycidoxypropyltrimethyl Oxysilane 8) (B) Monofunctional oxycyclobutane compound: OXT-212 (manufactured by Toagosei Co., Ltd.) Chemical name: 2-ethylhexyl oxycyclobutane 9) (B) Bifunctional oxycyclobutane compound: OXT-221 (manufactured by Toagosei Co., Ltd.) Chemical name: 3-ethyl-3{[(3-ethyloxybutane-3-yl)methoxy]methyl}oxybutane 10) photosensitization Agent: ANTHRACURE UVS-1331 (manufactured by Kawasaki Chemical Industry Co., Ltd.) Chemical name: 9,10-dibutoxyanthracene 11) (C) Photoacid generator: CPI-100P (solid content 50%) (manufactured by San-Apro Corporation )Chemical name: diphenyl[4-(phenylhydrothio)phenyl]sulfonium=hexafluoro-λ5-phosphate (phosphanuide) 12) (C) Photoacid generator: Omnicat 250 (manufactured by IGM resin) Chemical name: 4-isobutylphenyl (4-methylphenyl) iodonium hexafluorophosphate (phosphate) (solid content 75%) 13) (D) Black colorant: Pigment black 7 (carbon black)

From the obtained curable resin compositions of Examples 1 to 10 and Comparative Examples 1 to 4, a cured product (cured coating film) with a film thickness of 5 μm was obtained, and the cross cut and pencil hardness of the cured product were measured as follows. And dryness to touch after UV curing. The viscosity of the curable resin compositions of Examples 1 to 10 and Comparative Examples 1 to 4 was measured with a cone plate viscometer (TVE-33H manufactured by Toki Sangyo Co., Ltd.) at an ink temperature of 50°C and 100 rpm. All are in the range of 5~20mPa･s.

[Preparation of test substrates] Using an inkjet printer under the following conditions, the curable resin compositions of Examples 1 to 10 and Comparative Examples 1 to 4 were drawn on the base material, and then cured with UV to prepare test substrates respectively. . In addition, a glass substrate (110 mm×160 mm, thickness 1 mm) was used as the base material.・Film thickness after curing according to the drawing conditions of an inkjet printer: 5μm Device: Piezoelectric inkjet printer (use material printer DMP-2831 manufactured by Fujifilm Corporation (printing head temperature 50°C)) ・UV hardening conditions LED-UV lamp (FireEdge FE400 manufactured by Phoseon TECHNOLOGY) Exposure: 1500mJ/cm ² Wavelength: 365nm

[Cross cut] In accordance with JIS K 5600-5-6 1999, the cured coating films on each test substrate of the curable resin compositions of Examples 1 to 10 and Comparative Examples 1 to 4 obtained in [Preparation of Test Substrates] were separated using 1 mm intervals. Cut using a cross cutting guide to make 25 (5×5) squares with a width of 1mm in length and width. Apply transparent adhesive tape (width 25±1mm) to the squared part of the hardened coating film and use your fingers to Rub the tape firmly until the hardened coating film can be seen through. Within 5 minutes of adhesion, peel off the tape reliably (tape peeling) at an angle close to 60 degrees in 0.5 to 1.0 seconds, and check the state of the grid. After the hard coating film was produced, the cross-cut was placed at 23°C with a humidity of 50% RH for 3 hours (initial adhesion), and then placed in a constant temperature and humidity chamber (Espec Corporation) at a temperature of 85°C and a relative humidity of 85%. LHL-114) after 240h (85℃85%RH close adhesion), a total of 2 times. The evaluation criteria are as follows. If the evaluation criteria are other than "△" and "×", the adhesion between the cured coating film and the test substrate is good, and if the evaluation criteria are "◎", the adhesion is particularly good. ◎: The peeled squares remain 100% adhered and no defects are found. 〇: The peeled squares maintain 100% adhesion, and slight defects are found at the intersections of the squares. △: The peeled squares maintain 100% adhesion, and peeling occurs at the intersection of the squares. ×: The peeled squares are not 100% adhered. The results are shown in Table 2 below.

[Pencil hardness] [Preparation of test substrates] The pencil hardness of the surface of the cured coating film on each test substrate of the curable resin compositions of Examples 1 to 10 and Comparative Examples 1 to 4 obtained was in compliance with JIS K 5600-5-4 Measurements were carried out in 1999 and evaluation was carried out as follows. Evaluation criteria other than "×" indicate that the hardness of the cured coating film is high, and judgment criteria "◎" indicates particularly high hardness. ◎：H or above 〇：HB ×：B or less The results are shown in Table 2 below.

[Dryness to finger touch after UV curing (finger touch test)] The dryness to touch of the cured coating film on each of the test substrates of the curable resin compositions of Examples 1 to 10 and Comparative Examples 1 to 4 obtained in [Preparation of Test Substrates] was evaluated as follows. The evaluation criteria other than "×" indicate that the hardenability of the cured coating film surface is good, and the evaluation criteria "◎" indicates that the hardenability of the cured coating film surface is particularly good. ◎: No trace is left even if touched with fingers 〇: A slight trace will be left after touching with a finger, but there will be no problem in actual use. ×: Sticky when touched with fingers, pigment components remain on fingers The results are shown in Table 2 below.

[OD value] Each test substrate of the curable resin composition of Examples 1 to 10 and Comparative Examples 1 to 4 was produced in the same manner except that the film thickness after curing was changed to 10 μm or 20 μm in [Preparation of test substrate]. The OD value of the cured coating film is measured as follows. The glass substrate was attached to a transmission density meter (manufactured by Sakata Inx Engineering Co., Ltd., model: X-Rite 361T, light source wavelength: 400 to 800 nm) with the hardened coating side of the glass substrate facing the measuring device, and the OD value was evaluated. As a result, the OD value of each example and each comparative example in which the film thickness after hardening: 10 μm was 4 or more and 6 or less, and the OD value in each example and each comparative example whose film thickness after hardening: 20 μm was 6 or more, which is Sufficient OD value for use as black sunscreen. Furthermore, the film thickness after curing: 10 μm or 20 μm is determined by the same method as [Preparation of test substrate], using an inkjet printer to draw every 5 μm, then UV curing, and accumulating until a predetermined film thickness is formed.

From the evaluation results of the above OD value and the results shown in Table 2, it can be seen that each example using the curable resin composition of the present invention can not only have high light-shielding properties, but also have good surface hardening properties and can be used under high-temperature and high-humidity conditions. A cured film that exhibits stable adhesion and has high hardness after curing. Furthermore, the mass ratio of (a) the alicyclic epoxy compound having an ester bond in the molecule and (b) the alicyclic epoxy compound not having an ester bond in the molecule is set to 8 in a further preferred range. :100~25:100, and the mass ratio of the (B) oxybutane compound and the aforementioned (A) epoxy compound is set to a more preferable range of 10:100~20:100, Example 1 and Example 3 , Example 5, and Example 6, each evaluation result is the best result within the evaluation criteria. In particular, regarding cross-cutting under high-temperature and high-humidity conditions (adhesion at 85°C and 85%RH) and pencil hardness, the results are superior to those of other examples.

In comparison, the mass ratio of (a) an alicyclic epoxy compound with an ester bond in the molecule and (b) an alicyclic epoxy compound without an ester bond in the molecule is 43:100, which is outside the range. Comparative Examples 1 to 2 of ~50:100, and Comparative Example 3 which does not include (a) an alicyclic epoxy compound with an ester bond in the molecule, compared with the Example, the cross-cut (initial adhesion) is slightly deteriorated , regarding cross-cutting under high-temperature and high-humidity conditions (adhesion at 85°C and 85%RH), the hardened coating film peeled off, which was the worst result within the evaluation criteria. Furthermore, the pencil hardness of Comparative Examples 1 to 3 was also the worst among the evaluation criteria. In Comparative Example 4, although the cross-cut evaluation result was good, the pencil hardness and finger touch were the worst results within the evaluation criteria.

Claims (7)

A curable resin composition comprising (A) an epoxy compound, (B) an oxybutane compound, (C) a photoacid generator, and (D) a black colorant, Among the aforementioned (A) epoxy compounds, the mass ratio in the numerical range of 5:100 to 30:100 includes (a) an alicyclic epoxy compound having an ester bond in the molecule and (b) an alicyclic epoxy compound having no ester bond in the molecule. The alicyclic epoxy compound. The curable resin composition of claim 1, which has a viscosity of 5 to 20 mPa･s at 50°C. The curable resin composition of claim 1, wherein the alicyclic epoxy compound (b) having no ester bond in the molecule has a bifunctional epoxy group. The curable resin composition of claim 1 or 2, wherein the black colorant (D) is carbon black, and the amount is 100 parts by mass relative to the total of 100 parts by mass of the (A) epoxy compound and (B) the oxybutane compound. , containing more than 5 parts by mass. The curable resin composition of any one of claims 1 to 3, wherein the mass ratio of the aforementioned (B) oxybutane compound to the aforementioned (A) epoxy compound is in the range of 2:100 to 40:100 . For example, in the curable resin composition of claim 5, the aforementioned (A) epoxy compound contains (a) an alicyclic epoxy having an ester bond in the molecule at a mass ratio in the numerical range of 8:100 to 25:100. Compound, an alicyclic epoxy compound that does not have an ester bond within the molecule of (b). The curable resin composition of claim 6, wherein the mass ratio of the (B) oxybutane compound and the (A) epoxy compound is in the range of 10:100 to 20:100.