Methods for manufacturing thermosetting compositions and their cured products, fusible compositions, and structures

Abstract

This invention discloses a thermosetting composition. The thermosetting composition contains: a polythiol compound having disulfide bonds; a cyclic ether compound having a polyether chain and having two or more cyclic ether groups; a curing accelerator; and a photoradical generator.

Description

Technical Field

[0001] This disclosure relates to a thermosetting composition and its cured form, a photofusible composition, and a method for manufacturing a structure. Prior Technology

[0002] Photofusible compositions that can be melted by light irradiation are used for various purposes. For example, Patent Document 1 discloses an image forming apparatus having a recording member having a photofusible resin layer composed of a photofusible composition.

[0003] [Patent Document 1] Japanese Patent Application Publication No. 11-190883

[0004] In conventional photofusible compositions, organic solvents are required to remove the resin components that melt under light irradiation. However, from environmental, safety, and substrate damage perspectives, it is necessary for photofusible compositions to be able to remove the resin components that melt under light irradiation using aqueous solvents. By endowing photofusible compositions with this property, it is expected that they can be developed into a wider range of applications. Summary of the Invention

[0005] Therefore, the main objective of this disclosure is to provide a thermosetting composition that can form a cured product (photomeltable composition) that can be melted by light irradiation and whose resin components produced by melting under light irradiation can be removed by an aqueous solvent.

[0006] One aspect of this disclosure relates to a thermosetting composition. This thermosetting composition contains: a polythiol compound having disulfide bonds; a cyclic ether compound having a polyether chain and having two or more cyclic ether groups; a curing accelerator; and a photoradical generator. Based on this thermosetting composition, a cured product (photomeltable composition) can be formed that can be melted by light irradiation and whose resin components generated during light irradiation can be removed by an aqueous solvent.

[0007] While the reason for this effect is not yet determined, the inventors believe it to be as follows: First, by heating, a thermosetting composition can be cured to obtain a thermosetting composition containing disulfide bonds through the reaction of a polythiol compound and a cyclic ether compound. Next, by irradiating the obtained cured composition with light, a photoradical generator can break the disulfide bonds (-SS-) in the irradiated portion, thereby reducing the molecular weight. Through this reduction in molecular weight, the elastic modulus of that portion decreases, and the cured composition melts into a liquid. Furthermore, since it is speculated that the resin component produced by melting under light irradiation has more polyether chains or hydroxyl groups (derived from cyclic ether groups) and exhibits a tendency to be hydrophilic, it can be removed using an aqueous solvent.

[0008] Thermosetting components can further shorten curing time and further improve light solubility and water solubility. Therefore, as cyclic ether compounds, they can contain compounds with two cyclic ether groups and compounds with three or more cyclic ether groups.

[0009] From the viewpoint of reactivity and ease of acquisition, the cyclic ether group can be ethylene oxide.

[0010] Another aspect of this disclosure relates to a cured thermosetting composition. The cured thermosetting composition can be a light-melting composition. According to the cured thermosetting composition, it can be melted by light irradiation and the resin components generated during light irradiation can be removed by an aqueous solvent.

[0011] Another aspect disclosed herein relates to a photofusible composition. This photofusible composition contains: a reaction product of a polythiol compound having disulfide bonds and a cyclic ether compound having a polyether chain and having two or more cyclic ether groups; and a photoradical generator. According to this photofusible composition, it can be melted by light irradiation, and the resin components generated during melting under light irradiation can be removed by an aqueous solvent.

[0012] Another aspect of this disclosure relates to a method for manufacturing a structure. The method comprises: a process of photo-irradiating at least a portion of a first structure composed of a cured thermosetting composition or a photofusible composition; and a process of obtaining a second structure by developing the photo-irradiated first structure with an aqueous solvent.

[0013] This disclosure provides a method for manufacturing the thermosetting composition described in [1] to [3], the cured product of the thermosetting composition described in [4], the photofusible composition described in [5], and the structure described in [6]. [1] A thermosetting composition comprising: a polythiol compound having disulfide bonds; a cyclic ether compound having a polyether chain and having two or more cyclic ether groups; a curing accelerator; and a photoradical generator. [2] The thermosetting composition as described in [1] contains a compound having two cyclic ether groups and a compound having three or more cyclic ether groups as the aforementioned cyclic ether compounds. [3] The thermosetting composition as described in [1] or [2], wherein The aforementioned cyclic ether group is ethylene oxide. [4] A cured product of any one of the thermosetting compositions described in [1] to [3]. [5] A photomeltable composition comprising: a reaction product of a polythiol compound having disulfide bonds and a cyclic ether compound having a polyether chain and having two or more cyclic ether groups; and a photoradical generator. [6] A method for manufacturing a structure, comprising: a process of photo-irradiating at least a portion of a first structure composed of a cured thermosetting composition described in [4] or a photofusible composition described in [5]; and a process of obtaining a second structure by developing the photo-irradiated first structure with an aqueous solvent. [Invention Effects]

[0014] According to this disclosure, a thermosetting composition is provided that can form a cured product (photofusible composition) capable of melting under light irradiation and having its resin components formed during melting under light irradiation removed by an aqueous solvent. Furthermore, according to this disclosure, a cured product and a photofusible composition of a thermosetting composition capable of melting under light irradiation and having its resin components formed during melting under light irradiation removed by an aqueous solvent are provided. Additionally, according to this disclosure, a method for manufacturing a structure using a photofusible composition is provided. Implementation

[0015] The embodiments of the present invention will now be described in detail. However, this disclosure is not limited to the following embodiments.

[0016] In this specification, the term "process" includes not only independent processes, but also processes that cannot be clearly distinguished from other steps, as long as the intended function of the step is achieved. Furthermore, the numerical range indicated by "~" represents the range within which the values ​​before and after "~" are included as the minimum and maximum values, respectively.

[0017] Furthermore, in this specification, when there are multiple substances in the composition that correspond to each component, unless otherwise specified, the content of each component refers to the total amount of those multiple substances present in the composition. Also, unless otherwise specified, the illustrative materials may be used individually or in combination of two or more.

[0018] Furthermore, within the numerical ranges described in this specification, the upper or lower limit of a certain stage's numerical range can be replaced with the upper or lower limit of other stages' numerical ranges. Also, within the numerical ranges described in this specification, the upper or lower limit can be replaced with the values ​​shown in the embodiments. "A or B" may include either A or B, or both.

[0019] One embodiment of the thermosetting composition contains: a polythiol compound having disulfide bonds (hereinafter, sometimes referred to as "component (A)"); a cyclic ether compound having a polyether chain and having two or more cyclic ether groups (hereinafter, sometimes referred to as "component (B)"); a curing accelerator (hereinafter, sometimes referred to as "component (C)"); and a photoradical generator (hereinafter, sometimes referred to as "component (D)").

[0020] (A) Component: Polythiol compounds containing disulfide bonds (A) is a compound having a disulfide bond (-SS-) and two or more thiol groups (-SH). (A) can be, for example, a dithiol compound having two thiol groups (-SH). (A) can be a high molecular weight component of a polymer or oligomer. A compound having two thiol groups (-SH) can be considered as a compound consisting of two thiol groups and a group containing a disulfide bond and connecting the two thiol groups (the first connecting group).

[0021] (A) The molecular weight or number average molecular weight of the component can be, for example, 100~10,000,000, 200~3,000,000, 300~1,000,000, 400~10,000, or 500~5,000. Furthermore, the number average molecular weight is a polystyrene conversion value obtained using gel permeation chromatography (GPC) and a calibration curve based on standard polystyrene.

[0022] (A) Component has one or more (more than two) disulfide bonds within the molecule. The number of disulfide bonds in (A) component can be, for example, 1 to 1000 or 4 to 50.

[0023] Component (A) can be a compound having linear or branched molecular chains and terminal groups, with disulfide bonds in the molecular chains (e.g., polymers or oligomers). In this case, the terminal groups in component (A) can be thiol groups. When component (A) is such a compound, it tends to more readily form a cured product with excellent light-melting properties. The molecular chains in component (A) can contain disulfide bonds and polyether chains, or can be composed of disulfide bonds and polyether chains.

[0024] (A) The component can be, for example, a compound represented by formula (1): HS-(XSS)n1-X-SH (compound (1)). In the formula, X represents a polyether chain. The multiple Xs can be the same or different from each other. n1 represents an integer greater than or equal to 1. n1 can be greater than or equal to 1 or greater than 4, or less than or equal to 1000. When the component (A) is a compound represented by formula (1), the group represented by -(XSS)n1-X- is the first linking group. The compound obtained by extending the chain of compound (1) can be, for example, a Michael adduct of compound (1) or a thiocarbamate of compound (1).

[0025] The polyether chain X can be, for example, a polyoxyalkylene chain. The polyether chain X can be, for example, a group represented by -X1-OX2-OX3-. X1 to X3 can each be an alkyl group independently, or an alkyl group having 1 to 2 carbon atoms (e.g., methylene, ethyl group). Examples of polyether chains as X include -CH2CH2-O-CH2-O-CH2CH2-.

[0026] Commercially available products that are components (A) include, for example, polysulfide rubber LP series (dithiols with disulfide bonds, manufactured by TORAY FINE CHEMICALS CO., LTD.). Component (A) can also be obtained by converting the reactive functional groups (e.g., carboxyl groups, hydroxyl groups) and disulfide bonds at the ends of compounds into thiol groups. Examples of compounds with reactive functional groups and disulfide bonds at the ends include 3,3'-dithiodipropionic acid (manufactured by Tokyo Chemical Industry Co., Ltd.), dithiodiethanol, and cystamine.

[0027] (A) The content of the component can be more than 15% by mass, more than 25% by mass, or more than 35% by mass, or less than 80% by mass, less than 70% by mass, or less than 60% by mass, based on the total amount of thermosetting components.

[0028] (B) Composition: Cyclic ether compounds having polyether chains and having two or more cyclic ether groups. Component (B) is a compound having polyether chains and two or more cyclic ether groups. The resin component produced by melting under light irradiation through the presence of component (B) in the thermosetting composition has more polyether chains or hydroxyl groups (derived from cyclic ether groups) and exhibits a tendency to be hydrophilic, thus allowing it to be removed by aqueous solvents. Component (B) can be a high molecular weight component of a polymer or oligomer.

[0029] The cyclic ether group of component (B) can be a group obtained by removing one hydrogen atom from a cyclic ether compound. Specific examples of the cyclic ether group of component (B) include ethylene oxide (oxiranyl group, epoxy group), oxocyclobutyl (oxocyclobutyl), tetrahydrofuranyl, tetrahydropyranyl, etc. Among these, from the viewpoint of reactivity and ease of acquisition, the cyclic ether group can be ethylene oxide. That is, component (B) can be an ethylene oxide compound (epoxide compound) having a polyether chain and having two or more ethylene oxide (oxiranyl group, epoxy group). In addition, in this specification, the cyclic ether group includes a group having a cyclic ether structure (including the structure of a cyclic ether group). For example, ethylene oxide includes a group having an ethylene oxide structure (including the structure of an ethylene oxide (oxiranyl group, epoxy group)) such as glycidyl, glycidyl ether, glycidyl cyclohexyl, etc.

[0030] (B) The molecular weight or number average molecular weight of the component can be, for example, 100~1,000,000, 100~500,000, 100~10,000, 150~5,000, or 200~2,000. Furthermore, the number average molecular weight is a polystyrene conversion value obtained using gel permeation chromatography (GPC) and a calibration curve based on standard polystyrene.

[0031] When the cyclic ether group of component (B) is ethylene oxide (epoxy group), the epoxy equivalent of component (B) can be 50~2000 g / eq, 80~1500 g / eq, or 100~1000 g / eq.

[0032] Component (B) can be a compound having two cyclic ether groups (hereinafter, sometimes referred to as component (B1)) or a compound having three or more cyclic ether groups (hereinafter, sometimes referred to as component (B2)). Component (B1) can be considered as a compound consisting of two cyclic ether groups and a group containing a polyether chain and connecting the two cyclic ether groups (the second linking group). Component (B2) can be a compound having one or more cyclic ether groups as side chains or substituents of the second linking group in component (B1). Since component (B) can further shorten the curing time and further improve light meltability and water solubility, it can include both components (B1) and (B2).

[0033] Component (B1) can be a compound (e.g., a polymer or oligomer) having a linear molecular chain and terminal groups, and containing a polyether chain within the molecular chain. In this case, the terminal groups in component (B1) can be cyclic ether groups. When component (B) is component (B1), there is a tendency to readily remove the resin components generated during melting under light irradiation using aqueous solvents. The polyether chain, as a molecular chain, can have hydroxyl groups, alkyl groups, or other substituents. The molecular chain in component (B1) can contain polyether chains or can be composed of polyether chains.

[0034] (B1) Component (2) can be a compound represented by formula (2): Z-(Y)n2-Z (compound (2)). In the formula, Y represents a polyether chain and Z represents a cyclic ether group. The multiple Zs can be the same or different from each other. n2 represents an integer greater than or equal to 1. n2 can be greater than or equal to 1 or greater than 2, or less than or equal to 1000. When component (B1) is a compound represented by formula (2), the group represented by -(Y)n2- is the second linking group.

[0035] The polyether chain represented by Y can be, for example, a polyoxyalkylene chain. The polyether chain represented by Y can be, for example, a group represented by -Y1-OY2-OY3-. Y1 to Y3 can each be an alkyl group independently, or an alkyl group having 1 to 3 carbon atoms (e.g., methylene, ethyl, propyl). Examples of polyether chains represented by Y include -CH2CH2-O-CH2-CH2-O-CH2CH2-.

[0036] Commercially available products containing (B1) include, for example, the DENACOL EX series (EX-850, EX-851, EX-821, EX-830, EX-832, EX-841, EX-861, EX-920, manufactured by Nagase ChemteX Corporation).

[0037] Component (B2) can be a compound having one or more cyclic ether groups as the second linking group (as the polyether chain of Y) as the side chain in component (B1).

[0038] Commercially available products containing (B2) include, for example, the DENACOL EX series (EX-614B, EX-313, EX-512, EX-521, manufactured by Nagase ChemteX Corporation).

[0039] The content of component (B) (the total of component (B1) and component (B2)) can be more than 15% by mass, more than 25% by mass, or more than 35% by mass, or less than 80% by mass, less than 70% by mass, or less than 60% by mass, based on the total amount of thermosetting components.

[0040] The mass ratio of component (B2) to component (B) (the total of components (B1) and (B2)) (the mass ratio of component (B2) to component (B) (the total of components (B1) and (B2)) can be 0.01 to 0.40. When this mass ratio is 0.01 or higher, there is a tendency to further shorten the curing time of the thermosetting composition; when this mass ratio is 0.40 or lower, there is a tendency to further improve the light melt and water solubility. This mass ratio can be 0.02 or higher, or 0.03 or higher, or 0.35 or lower, 0.30 or lower, 0.25 or lower, 0.20 or lower, 0.15 or lower, 0.10 or lower, or 0.05 or lower.

[0041] The equivalence ratio of the cyclic ether group of component (B) to the thiol group of component (A) (cyclic ether group of component (B) / thiol group of component (A)) can be, for example, 0.5 to 2.5. When the equivalence ratio is 0.5 or higher, it tends to further improve the water solubility of the thermosetting composition; when the equivalence ratio is 2.5 or lower, it tends to further improve the light melt properties. The equivalence ratio can be 0.8 or higher, 1.0 or higher, 1.2 or higher, or 1.5 or higher, or 2.2 or lower or 2.0 or lower.

[0042] (C) Ingredients: Curing accelerator Component (C) is a component used to promote the (curing) reaction of components (A) and (B), including components that act as catalysts for the curing reaction (catalyst-type curing agents). Examples of components (C) include amine compounds, imidazole derivatives, quaternary ammonium salts, organometallic salts, and phosphorus compounds.

[0043] Examples of amine compounds include dicyandiamine, trimethylamine, triethylamine, tripropylamine, tributylamine, tri-n-octylamine, dimethylethylamine, dimethylpropylamine, dimethylbutylamine, dimethyl-n-octylamine, 1,4-diacrylbicyclo[2.2.2]octane, 1,8-diacrylbicyclo[5.4.0]undecane-7-ene, benzyldimethylamine, 4-methyl-N,N-dimethylbenzylamine, 2,4,6-tris(dimethylaminomethyl)phenol, and 4-dimethylaminopyridine.

[0044] Examples of imidazole derivatives include 1-(1-cyanomethyl)-2-ethyl-4-methyl-1H-imidazolium, 2-ethyl-4-methylimidazolium, 2-methylimidazolium, 2-phenylimidazolium, 1-cyanoethyl-2-phenylimidazolium, 2-phenyl-4,5-dihydroxymethylimidazolium, 2-phenyl-4-methyl-5-hydroxymethylimidazolium, 2,4,5-triphenylimidazolium, 1-benzyl-2-imidazolium, 1,2-dimethylimidazolium, and 1-benzyl-2-phenylimidazolium.

[0045] Examples of quaternary ammonium salts include tetramethylammonium chloride, tetraethylammonium chloride, tetrabutylammonium chloride, benzyltrimethylammonium chloride, benzyltriethylammonium chloride, benzyltributylammonium chloride, tetramethylammonium bromide, tetraethylammonium bromide, tetrabutylammonium bromide, benzyltrimethylammonium bromide, benzyltriethylammonium bromide, tetramethylammonium iodide, tetraethylammonium iodide, tetrabutylammonium iodide, and benzyltributylammonium iodide.

[0046] Examples of organometallic salts include bis(2,4-pentanedione)zinc(II), zinc octanoate, zinc naphthenate, cobalt naphthenate, copper naphthenate, iron acetone, nickel octanoate, and manganese octanoate.

[0047] Examples of phosphorus compounds include tetraphenylphosphine tetratolylboryl, tetraphenylphosphine tetraphenylboryl, triphenylphosphine, tritolylphosphine, tri(4-chlorophenyl)phosphine, tri(4-methoxyphenyl)phosphine, tri(2,6-dimethoxyphenyl)phosphine, triphenylphosphine triphenylborane, tetraphenylphosphine dicyandiamide, and tetraphenylphosphine tetra(4-methylphenyl)borate.

[0048] (C) The content of the component, based on the total amount of thermosetting components, can be more than 0.01% by mass, more than 0.1% by mass, or more than 0.5% by mass, or less than 10% by mass, less than 5% by mass, or less than 2% by mass.

[0049] (D) Component: Photoradical generator Component (D) is a component that generates free radicals in the cured thermosetting composition upon light irradiation. Examples of component (D) include hydrogen-absorption type photoradical polymerization initiators that generate free radicals by removing hydrogen from other molecules upon light irradiation, and intramolecular cleavage type photoradical polymerization initiators that generate two free radicals by photolytically degrading the substance itself upon light irradiation. Since it readily undergoes a (photomelting) reaction, component (D) can be an intramolecular cleavage type photoradical polymerization initiator.

[0050] Examples of hydrogen-abstracting photoradical generators include hexaarylbisimidazole (HABI) compounds, diphenyl ketone compounds, 9-oxothiosulfate compounds, fumonisins, and α-diketone compounds.

[0051] Examples of HABI compounds include 2,2'-bis(o-chlorophenyl)-4,4',5,5'-tetraphenylbisimidazole (e.g., 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-bisimidazole), 2,2'-bis(o-bromophenyl)-4,4',5,5'-tetraphenylbisimidazole, and 2,2'-bis(o,p-dichlorophenyl)-4,4',5,5' Tetraphenylbisimidazole, 2,2'-bis(o-chlorophenyl)-4,4',5,5'-tetra(m-methoxyphenyl)bisimidazole, 2,2'-bis(o,o'-dichlorophenyl)-4,4',5,5'-tetraphenylbisimidazole, 2,2'-bis(o-nitrophenyl)-4,4',5,5'-tetraphenylbisimidazole, 2,2'-bis(o-methylphenyl)-4,4',5,5'-tetraphenylbisimidazole, etc.

[0052] Examples of diphenyl ketone compounds include 4,4'-bis(dimethylamino)diphenyl ketone and 4,4'-bis(diethylamino)diphenyl ketone.

[0053] Examples of 9-oxosulfurosteroid compounds include 9-oxosulfurosteroid, 2-isopropyl9-oxosulfurosteroid, 2-dodecyl9-oxosulfurosteroid, 2-cyclohexyl9-oxosulfurosteroid, 2,4-diethyl9-oxosulfurosteroid, 2,4-dimethyl9-oxosulfurosteroid, 1-phenoxy9-oxosulfurosteroid, and 1-methoxycarbonyl9-oxosulfurosteroid. Oxysulfuro-steril, 2-ethoxycarbonyl-9-oxosulfuro-steril, 3-(2-methoxyethoxycarbonyl)-9-oxosulfuro-steril, 4-butoxycarbonyl-9-oxosulfuro-steril, 3-butoxycarbonyl-7-methyl-9-oxosulfuro-steril, 3,4-di-[2-(2-methoxyethoxy)-ethoxycarbonyl]-9-oxosulfuro-steril, 2-chloro-9-oxosulfuro-steril 1-Ethoxycarbonyl-3-ethoxy9-oxosulfuron-methyl, 1-Ethoxycarbonyl-3-chloro9-oxosulfuron-methyl, 1-chloro-4-n-propoxy9-oxosulfuron-methyl, 2-methyl-6-dimethoxymethyl-9-oxosulfuron-methyl, 2-methyl-6-(1,1-dimethoxybenzyl)-9-oxosulfuron-methyl, 6-ethoxycarbonyl-2- Methoxy-9-oxothiocin, 6-ethoxycarbonyl-2-methyl-9-oxothiocin, 1-ethoxycarbonyl-3-(1-methyl-1-morpholinylethyl)-9-oxothiocin, 2-morpholinylmethyl-9-oxothiocin, 2-methyl-6-morpholinylmethyl-9-oxothiocin, 9-oxothiocin-2-carboxylic acid polyethylene glycol ester, etc.

[0054] Examples of genistein compounds include 9-genistein, 3,4-benzo-9-genistein, 2-dimethylamino-9-genistein, 2-methoxy-9-genistein, 2-chloro-9-genistein, 2,7-dichloro-9-genistein, 2-bromo-9-genistein, 2,7-dibromo-9-genistein, 2-nitro-9-genistein, and 2-acetoxy-9-genistein.

[0055] Examples of α-diketone compounds include benzyl (also known as diphenylethylenedione or diphenylmethyldione compounds).

[0056] Examples of intramolecular cleavage-type photoradical generators include benzyl ketal photoradical generators, α-aminoalkyl acetophenone photoradical generators, α-hydroxyalkyl acetophenone photoradical generators, α-hydroxyacetophenone photoradical generators, and acetylated phosphine oxide photoradical generators.

[0057] Examples of benzyl ketal photoradical generators include 2,2-dimethoxy-1,2-diphenylethane-1-one (Omnirad 651).

[0058] Examples of α-aminoalkylacetophenone-based photoradical generators include 2-benzyl-2-dimethylamino-1-(4-morpholinylphenyl)-butanone-1 (Omnirad 369), 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinylpropane-1-one (Omnirad 907), and 2-dimethylamino-2-(4-methyl-benzyl)-1-(4-morpholinyl-4-yl-phenyl)-butane-1-one (Omnirad 379EG).

[0059] Examples of α-hydroxyalkylacetophenone-based photoradical generators include 1-hydroxy-cyclohexyl-phenyl-one (Omnirad 184).

[0060] Examples of α-hydroxyacetophenone-based photoradical generators include 2-hydroxy-1-{4-[4-(2-hydroxy-2-methyl-propionic)-benzyl]-phenyl}-2-methyl-propane-1-one (Omnirad 127) and 2-hydroxy-2-methyl-1-phenyl-propane-1-one (Omnirad 1173).

[0061] Examples of phosphine oxide photoradical generators include 2,4,6-trimethylbenzoyl-diphenylphosphine oxide (Omnirad TPO H) and bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide (Omnirad 819).

[0062] (D) The content of the component can be more than 1% by mass, more than 5% by mass, or more than 10% by mass, or less than 30% by mass, less than 20% by mass, or less than 15% by mass, based on the total amount of thermosetting components.

[0063] Thermosetting compositions may further contain components other than (A), (B), (C), and (D). Examples of such other components include, for instance, plasticizers, tackifiers and other adhesive agents, antioxidants, colorless dyes, sensitizers, coupling agents and other adhesion modifiers, polymerization inhibitors, light stabilizers, defoamers, fillers, chain transfer agents, thixotropic agents, flame retardants, mold release agents, surfactants, lubricants, antistatic agents, and other additives. Well-known additives may be used. The content of these other components, based on the total amount of the thermosetting composition, may be 0–95% by mass, 0.01–50% by mass, or 0.1–10% by mass.

[0064] Thermosetting compositions can be used as varnishes of thermosetting compositions diluted with solvents. Examples of solvents include aromatic hydrocarbons such as toluene, xylene, symmetrical trimethylbenzene, cumene, and p-isopropyltoluene; aliphatic hydrocarbons such as hexane and heptane; cyclic alkanes such as methylcyclohexane; cyclic ethers such as tetrahydrofuran and 1,4-dimethylalkanes; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, and 4-hydroxy-4-methyl-2-pentanone; esters such as methyl acetate, ethyl acetate, butyl acetate, methyl lactate, ethyl lactate, and γ-butyrolactone; carbonates such as ethyl carbonate and propylene carbonate; and acetamides such as N,N-dimethylformamide, N,N-dimethylacetamide, and N-methyl-2-pyrrolidone (NMP). The content of solid components in varnish, that is, the total content of varnish excluding solvents, can be 10~95% by mass, 15~70% by mass, or 20~50% by mass, based on the total mass of varnish.

[0065] Thermosetting compositions can be prepared, for example, by a process involving mixing or kneading components (A), (B), (C), and (D), and other components added as needed. Mixing and kneading can be performed using conventional dispersers such as mixers, pounders, three-roll mills, ball mills, and bead mills.

[0066] Thermosetting compositions can be cured by heating. Heating the thermosetting composition initiates a (curing) reaction with components (A) and (B) (e.g., a compound having a glycidyl ether group as a cyclic ether group). Component (C) can promote the reaction. The reaction product of components (A) and (B) can be, for example, a compound (polymer) containing a structure represented by the following formula. On the other hand, component (D) participates less in the (curing) reaction, and the cured product can contain the reaction product of components (A) and (B) and component (D).

[0067] [Chemistry 1]

[0068] In the formula, X represents the first linking group, and Y represents the second linking group. m represents an integer greater than or equal to 1. For example, m can be greater than or equal to 50, 100, 500, or 1000. * represents a bond.

[0069] The heating temperature of the thermosetting composition can be, for example, 0~200℃, or 30~150℃ or 60~100℃. The heating time of the thermosetting composition can be, for example, 0.1~168 hours, or less than 72 hours, less than 24 hours, less than 12 hours, less than 6 hours, less than 4 hours, less than 3 hours, or less than 2 hours.

[0070] Cured thermosetting compositions can be formed into various shapes. For example, cured compositions formed into a film (thin film) can be used as films. Cured compositions formed into a block can be used as blocks. There are no particular limitations on the method of forming film (thin film) or block cured compositions, and known methods can be used.

[0071] The cured thermosetting composition has the property of melting upon light irradiation. The light used for irradiation can be, for example, light with a wavelength of 365 nm. Irradiation with this light can melt the cured composition. The light exposure intensity can be, for example, 1000 mJ / cm² or higher. In this specification, the exposure intensity refers to the product of illuminance (mW / cm²) and irradiation time (seconds). Light irradiation can be performed directly on the object being irradiated or through glass or the like. There are no particular limitations on the light source used for irradiation; examples include LED lamps, mercury lamps (low-pressure, high-pressure, ultra-high-pressure, etc.), metal halide lamps, excimer lamps, and xenon lamps. Among these, the light source used for irradiation can be an LED lamp, a mercury lamp, or a metal halide lamp.

[0072] By irradiating the cured thermosetting composition with light, component (D) in the cured composition causes the disulfide bonds (-SS-) in the reaction products of components (A) and (B) to break. This reduces the molecular weight of the reaction products of components (A) and (B), making them liquid. The cured thermosetting composition melts upon light irradiation and can therefore be called a photomeltable composition. This photomeltable composition may contain: the reaction products of components (A) and (B), and component (D).

[0073] The resin component produced by melting a cured thermosetting component (a light-melting component) under light irradiation has a high proportion of polyether chains or hydroxyl groups and exhibits a tendency to be hydrophilic. Therefore, this resin component can be removed using an aqueous solvent. Examples of aqueous solvents include water and mixtures of water and hydrophilic organic solvents. In a mixture of water and a hydrophilic organic solvent, the proportion of water can be set to, for example, 80% by mass or more. A pH adjuster can be added to the aqueous solvent, for example.

[0074] Examples of water types include tap water, natural water, purified water, distilled water, ion-exchanged water, pure water, and ultrapure water (Milli-Q water, etc.). Milli-Q water specifically refers to ultrapure water produced using Merck Millipore's Milli-Q water production equipment. Due to reduced impurities, water can be classified as purified water, distilled water, ion-exchanged water, pure water, or ultrapure water.

[0075] Examples of hydrophilic organic solvents include alcohols such as methanol, ethanol, 2-propanol, and 1,2-propanediol; and glycol ethers such as ethylene glycol monomethyl ether, propylene glycol monomethyl ether, ethyl cellosolve, propylene glycol monopropyl ether, propylene glycol monoisopropyl ether, butyl cellosolve, ethylene glycol monoisobutyl ether, propylene glycol monobutyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, and dipropylene glycol monomethyl ether.

[0076] Examples of pH adjusters include inorganic acids, inorganic bases, organic acids, and organic bases. Examples of inorganic acids include nitric acid, sulfuric acid, hydrochloric acid, phosphoric acid, and boric acid. Examples of inorganic bases include sodium hydroxide, potassium hydroxide, and calcium hydroxide. Examples of organic acids include formic acid, acetic acid, propionic acid, butyric acid, acrylic acid, benzoic acid, and pyridinecarboxylic acid. Examples of organic bases include primary amines, secondary amines, tertiary amines, tetramethylammonium hydroxide, tetraethylammonium hydroxide, and imidazole compounds.

[0077] The thermosetting composition of this embodiment can be used for temporary fixation adhesives, medical adhesives, easily removable adhesives, reflow sheet materials, photoresist materials (photoresist that can be developed with alkali-free methods), 3D printing machine materials, and other applications.

[0078] A method for manufacturing a structure according to one embodiment includes: a process of photo-irradiating at least a portion of a first structure composed of a cured thermosetting composition or a photofusible composition; and a process of obtaining a second structure by developing the photo-irradiated first structure with an aqueous solvent. The method for manufacturing the structure is a method for manufacturing the second structure. The second structure is a structure obtained by removing a portion of the photo-irradiated thermosetting composition from the first structure, and may be a structure with a recess of a desired shape.

[0079] The first structure is obtained by forming a cured thermosetting composition or a photofusible composition into various shapes. The first structure can have shapes such as film-like or block-like. There are no particular limitations on the method of forming the first structure, and known methods can be used.

[0080] The type of light, the exposure amount, the irradiation, and the light source used for irradiation when irradiating the first structure can be the same as those described above.

[0081] In the cured form of thermosetting compositions or photoresist compositions, similar to positive photoresist, the areas irradiated by light are removed by an aqueous solvent during development, while the areas not irradiated by light remain, thus enabling the formation of recesses of the desired shape. When the first structure is irradiated by light, for example, by using a photomask, it is possible to selectively irradiate a specified area (the recess-forming area).

[0082] By developing the first structure exposed to light using an aqueous solvent, a second structure can be obtained by removing a portion of the thermosetting component or a photofusible component from the first structure. The aqueous solvent can be the same as described above.

[0083] The second structure can be a film, block, or the like with recesses of the desired shape. Specific examples of the second structure include patterns of semiconductor resists and substrate materials. [Example]

[0084] The following examples illustrate this disclosure in more detail. However, this disclosure is not limited to these examples.

[0085] The compounds shown below were prepared. (A)Ingredients: (A-1) Polysulfide rubber LP-3 (dithiol compound, manufactured by TORAY FINE CHEMICALS CO., LTD.) (B) Ingredients: (B1) Ingredients: (B1-1)DENACOL EX-841 (Ethylene oxide compound, number of ethylene oxide alkyl groups: 2, manufactured by Nagase ChemteX Corporation, epoxy equivalent: 372 g / eq) (B2) Ingredients: (B2-1)DENACOL EX-512 (Ethylene oxide compound, number of ethylene oxide alkyl groups: 4, manufactured by Nagase ChemteX Corporation, epoxy equivalent: 168g / eq) (C) Ingredients: (C-1)DMP-30(2,4,6-tris(dimethylaminomethyl)phenol) (D) Ingredients: (D-1)Omnirad 651 (2,2-Dimethoxy-1,2-diphenylethane-1-one (manufactured by IGM Resins BV))

[0086] (Examples 1-4 and Comparative Example 1) [Preparation of thermosetting compositions] Components (A) and (D) as described in Table 1 and in the amounts (parts by mass) were added to a 35ml ointment jar. The mixture was stirred for 90 seconds at 2000 rpm using a self-rotating mixer (THINKY CORPORATION, trade name: Awatorirentarou ARE-310), and then heated at 90°C for 15 minutes. After cooling, components (B) and (C) were added, and the mixture was stirred for 90 seconds at 2000 rpm using a self-rotating mixer to obtain the thermosetting compositions of Examples 1-4 and Comparative Example 1.

[0087] [Curing Test] The prepared thermosetting composition was placed in a 90°C thermostat bath (manufactured by ESPEC Co., Ltd., trade name: STH-120). Every hour, the surface of the thermosetting composition was gently poked with a spatula. The curing time was defined as one hour after the thermosetting composition no longer adhered to the spatula, and the curing properties of the thermosetting composition were evaluated. The results are shown in Table 1.

[0088] [Membrane fabrication] The prepared thermosetting composition was injected into a mold frame holding a 0.5 mm thick silicone gasket, a polyethylene terephthalate film (molded PET, manufactured by Nakamoto Packs Co., Ltd., trade name: NS-38+A-500, thickness 70 μm) that had undergone a demolding treatment, and a glass plate. The mold frame containing the injected thermosetting composition was placed in a constant temperature bath at 90 °C and heated for the curing time determined in the above curing test (curing time recorded in Table 1) to obtain a film composed of cured thermosetting composition.

[0089] [Light Melting Test] For the films fabricated above, LEDs (main wavelength: 365nm, illuminance: 1000mW / cm²) were used to irradiate the films with the exposure levels described in Table 1. After irradiation, the PET film was peeled off, and the presence or absence of liquefaction in the irradiated areas was confirmed by visual observation and palpation with a scraper. A case where the irradiated areas were entirely liquid and completely free of solid matter was rated as "A," while a case where the irradiated areas were mostly liquid but retained some solid matter was rated as "B." In Comparative Example 1, the irradiated areas did not liquefy and remained solid. The results are shown in Table 1.

[0090] [Water solubility after light melting] Weigh 0.05g of the liquid portion (resin component) from the area irradiated by light in the photomeltability test into a sample vial, add 5g of pure water, and stir gently. The resin component is rated "A" if it dissolves in pure water without turbidity and remains transparent, and "B" if it is slightly turbid. The results are shown in Table 1.

[0091] [Table 1] Comparative Example 1 Example 1 Example 2 Example 3 Example 4 (A) (A-1) 42 36 41 41 41 (B) (B1) (B1-1) 57 50 38 41 43 (B2) (B2-1) - - 8 4 2 (C) (C-1) 1 1 1 1 1 (D) (D-1) - 13 13 13 13 (B) cyclic ether group / (A) thiol group 1.9 1.9 1.8 1.7 1.6 Curing time (hours) 16 16 2 3 4 Light melting (Exposure (mJ / cm2)) - A (3000) B (10000) A (5000) A (4000) Water solubility after light melting - A B B A

[0092] As shown in Table 1, the thermosetting compositions of Examples 1-4 exhibit photomeltability, and the resin components also exhibit excellent water solubility. As described above, it has been confirmed that the thermosetting compositions disclosed herein can form a cured product (photomeltable composition) that can be melted by light irradiation and whose resin components produced by melting under light irradiation can be removed by an aqueous solvent.

Claims

1. A thermosetting composition comprising: a polythiol compound having disulfide bonds and a polyether chain; a cyclic ether compound having a polyether chain and having two or more cyclic ether groups; a curing accelerator; and a photoradical generator.

2. The thermosetting composition as claimed in claim 1, comprising a compound having two cyclic ether groups and a compound having three or more cyclic ether groups as the aforementioned cyclic ether compounds.

3. The thermosetting composition as described in claim 1 or claim 2, wherein the aforementioned cyclic ether group is ethylene oxide.

4. A cured product of the thermosetting composition described in any one of claims 1 to 3.

5. A photomeltable composition comprising: a reaction product of a polythiol compound having disulfide bonds and a polyether chain and a cyclic ether compound having a polyether chain and having two or more cyclic ether groups; and a photoradical generator.

6. A method for manufacturing a structure, comprising: a process of photo-irradiating at least a portion of a first structure composed of a cured thermosetting composition as described in claim 4 or a photofusible composition as described in claim 5; and a process of obtaining a second structure by developing the photo-irradiated first structure with an aqueous solvent.