Liquid curable composition, cured product, and method for producing individual cured products.

Abstract

The present invention provides a liquid curable composition that can form a cured product in a desired shape, suppress yellowing of the formed cured product, and further improve the brightness of an optical device when the cured product is mounted on the optical device. [Solution] A liquid curable composition comprising a curable organopolysiloxane compound, a silane coupling agent having two or more alkoxysilyl groups or silanol groups in its molecule, and a thermal acid generator, wherein the liquid curable composition contains less than 1 part by mass of a compound having an acid anhydride per 100 parts by mass of the solid content of the liquid curable composition, and the refractive index of the liquid curable composition is 1.50 or higher.

Description

[Technical Field]

[0001] The present invention relates to a liquid curable composition, a cured product, and a method for producing individual pieces of the cured product. [Background technology]

[0002] Liquid curable compositions are widely used as raw materials for optical components and molded articles, as adhesives and coatings for semiconductor elements such as optoelectronic devices, transistors, and sensors, and various improvements have been made to them according to these applications. For example, Patent Document 1 discloses a liquid curable composition improved for use as a fixative for optical elements.

[0003] In the use of such liquid curable compositions, the liquid curable composition may be applied to a sheet-like substrate, the applied coating is heated and dried to form a layer of the curable composition, and then further heated and cured to form a plate-like cured product. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] International Publication No. 2014 / 069508 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] However, it was sometimes difficult to stably form the liquid curable composition into a plate-shaped cured product, and even when it was possible to form a plate-shaped cured product, yellowing sometimes occurred when the plate-shaped cured product was exposed to high temperatures for a long period of time. In addition, it was sometimes difficult to achieve a high level of brightness when the plate-shaped cured product was mounted on an optical device.

[0006] The object of the present invention is to provide a liquid curable composition that can form a cured product in a desired shape, suppress yellowing of the formed cured product, and further improve the brightness of an optical device when the cured product is mounted on an optical device. [Means for solving the problem]

[0007] According to the present invention, A liquid curable composition, A curable organopolysiloxane compound, A silane coupling agent having two or more alkoxysilyl groups or silanol groups in its molecule, It contains a thermal acid generator, The liquid curable composition contains a compound having an acid anhydride in less than 1 part by mass per 100 parts by mass of solid content of the liquid curable composition. A liquid curable composition is provided, wherein the refractive index of the liquid curable composition is 1.50 or higher. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a liquid curable composition that can form a cured product in a desired shape, suppress yellowing of the formed cured product, and further improve the brightness of an optical device when the cured product is mounted on an optical device. [Modes for carrying out the invention]

[0009] The following embodiments are not intended to limit the invention as defined in the claims, and not all combinations of features described in the embodiments are essential to the invention. Two or more of the features described in the embodiments may be combined in any way.

[0010] <Liquid curable composition according to this embodiment> The liquid curable composition according to this embodiment contains a curable organopolysiloxane compound, a silane coupling agent having two or more alkoxysilyl or silanol groups in its molecule, and a thermoacid generator, wherein the liquid curable composition contains less than 1 part by mass of a compound having an acid anhydride per 100 parts by mass of solid content of the liquid curable composition. This allows the liquid curable composition according to this embodiment to form a cured product in a desired shape and suppresses yellowing of the formed cured product. Furthermore, the refractive index of the liquid curable composition according to this embodiment is 1.50 or higher. This makes it possible to improve the brightness of an optical device when the cured product of the liquid curable composition according to this embodiment is mounted on an optical device.

[0011] A "liquid curable composition" refers to "a viscous liquid that is fluid at room temperature." Here, room temperature is defined as 23°C. Because liquid curable compositions possess these properties, they can be used in coating processes.

[0012] The applications of the liquid curable composition according to this embodiment are not particularly limited and can be used as a raw material for optical components and molded articles, as an adhesive for semiconductor elements such as optoelectronic elements, transistors, and sensors. The liquid curable composition can also be applied to a sheet-like substrate, and the applied coating can be heated and dried to form a layer of the curable composition, which can then be used as an adhesive film. In one embodiment, the liquid curable composition can be cut into a grid pattern after curing and used as individual cured pieces in optical devices and the like. For example, an optical device includes a support member, an insulating substrate provided on the support member on which optoelectronic elements are laminated, and a light-transmitting insulating member bonded to the insulating substrate via an adhesive, and light from the optoelectronic elements is extracted through the insulating member. The plate-shaped cured product (i.e., plate-shaped cured product) of the liquid curable composition according to this embodiment can be used as an insulating member in such an optical device.

[0013] (Compound containing an acid anhydride (B')) The liquid curable composition may contain a compound having an acid anhydride (hereinafter sometimes referred to as "component (B')"). By including component (B'), the curability of the liquid curable composition and the toughness for maintaining the shape of the cured product can be improved. However, the inventors have found that yellowing that occurs when the cured product of the liquid curable composition is exposed to high temperatures for a long time is caused by the compound having an acid anhydride in the liquid curable composition. Therefore, the amount of the compound having an acid anhydride in the liquid curable composition according to this embodiment is set to less than 1 part by mass per 100 parts by mass of the solid content (i.e., active ingredient) of the liquid curable composition. Here, "active ingredient" refers to the components contained in the liquid curable composition excluding the solvent. The amount of the compound having an acid anhydride in the liquid curable composition may be less than 0.5 parts by mass in another embodiment, 0.1 parts by mass in yet another embodiment, and 0 parts by mass in yet another embodiment, per 100 parts by mass of the solid content of the liquid curable composition. With the amount of the acid anhydride compound in the liquid curable composition described above, yellowing of the cured product of the liquid curable composition is suppressed even when exposed to high temperatures for a long period of time.

[0014] In one embodiment, the compound (B') having an acid anhydride is exemplified by compounds used as silane coupling agents. For example, tri(C1 to C6)alkoxysilyl(C2 to C8)alkyl succinic anhydrides such as 2-(trimethoxysilyl)ethyl succinic anhydride, 2-(triethoxysilyl)ethyl succinic anhydride, 3-(trimethoxysilyl)propyl succinic anhydride, 3-(triethoxysilyl)propyl succinic anhydride; di(C1 to C6)alkoxymethylsilyl(C2 to C8)alkyl succinic anhydrides such as 2-(dimethoxymethylsilyl)ethyl succinic anhydride; and 2-(methoxydimethylsilyl)ethyl succinic anhydride. Examples include alkoxydimethylsilyl (carbon 2 to 8) alkyl succinic anhydrides (prime numbers 1 to 6); trihalogenosilyl (carbon 2 to 8) alkyl succinic anhydrides such as 2-(trichlorosilyl)ethyl succinic anhydrides and 2-(tribromosilyl)ethyl succinic anhydrides; dihalogenomethylsilyl (carbon 2 to 8) alkyl succinic anhydrides such as 2-(dichloromethylsilyl)ethyl succinic anhydrides; and halogenodimethylsilyl (carbon 2 to 8) alkyl succinic anhydrides such as 2-(chlorodimethylsilyl)ethyl succinic anhydrides.

[0015] (Refractive index) The refractive index of the liquid curable composition according to this embodiment is 1.50 or higher. In another embodiment, the refractive index of the liquid curable composition can be 1.52 or higher, in yet another embodiment, 1.54 or higher, in yet another embodiment, 1.56 or higher, in yet another embodiment, 1.58 or higher, and in yet another embodiment, 1.60 or higher. This makes it possible to improve the brightness of the optical device when the cured product of the liquid curable composition is mounted on the optical device. Furthermore, the upper limit of the refractive index of the liquid curable composition is not particularly limited, but in one embodiment it can be 1.70 or lower, in another embodiment, 1.68 or lower, in yet another embodiment, 1.66 or lower, in yet another embodiment, 1.64 or lower, and in yet another embodiment, 1.62 or lower.

[0016] Furthermore, there is a correlation between the refractive index of the liquid curable composition and the refractive index of its cured product. In other words, if the refractive index of the liquid curable composition is high, the refractive index of its cured product will also be high. Therefore, by setting the refractive index of the liquid curable composition to 1.50 or higher, the brightness of the optical device can be improved when its cured product is mounted on the optical device. Also, since this correlation is often satisfied when the concentration of the solid content (i.e., active ingredient) of the liquid curable composition is high, the refractive index of the liquid curable composition can be measured when the concentration of the active ingredient of the liquid curable composition is 70% by mass or more in one embodiment, 80% by mass or more in another embodiment, 90% by mass or more in yet another embodiment, and 95% by mass or more in yet another embodiment.

[0017] The refractive index of a liquid curable composition can be measured at 25°C using a commercially available refractive index measuring device (manufactured by Atago Co., Ltd., product name "Abbe Refractometer DR-M2") with sodium D line (wavelength 589 nm) as the light source.

[0018] (Curing organopolysiloxane compound (A)) The liquid curable composition according to this embodiment contains a curable organopolysiloxane compound (A) (hereinafter sometimes referred to as "component (A)"). By containing component (A), the liquid curable composition is more likely to exhibit excellent curability and to exhibit toughness and light resistance necessary to stably maintain the shape of the cured product.

[0019] The curable organopolysiloxane compound (A) is a compound having a carbon-silicon bond and a siloxane bond (-Si-O-Si-) in its molecule. Since component (A) is a thermosetting compound, it can have at least one functional group selected from the group consisting of functional groups that can undergo condensation reactions upon heating and functional groups that can undergo condensation reactions via hydrolysis. Such a functional group can be at least one selected from the group consisting of hydroxyl groups and alkoxy groups, for example, a hydroxyl group or an alkoxy group having 1 to 10 carbon atoms.

[0020] There are no restrictions on the main chain structure of the curable organopolysiloxane compound (A), and it may be linear, ladder-like, or cage-like. For example, a linear main chain structure is represented by the structure shown in formula (a-1), a ladder-like main chain structure is represented by the structure shown in formula (a-2), and a cage-like main chain structure is represented by the structure shown in formula (a-3).

[0021] [ka]

[0022] [ka]

[0023] [ka]

[0024] In formulas (a-1) to (a-3), Rx, Ry, and Rz each independently represent a hydrogen atom or an organic group. The organic group can be an unsubstituted or substituted alkyl group, an unsubstituted or substituted cycloalkyl group, an unsubstituted or substituted alkenyl group, an unsubstituted or substituted aryl group, or an alkylsilyl group. The multiple Rx in formula (a-1), the multiple Ry in formula (a-2), and the multiple Rz in formula (a-3) may be the same or different. However, not both Rx in formula (a-1) can be hydrogen atoms.

[0025] Examples of the unsubstituted or substituted alkyl groups include C1 to C10 alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, n-pentyl, isopentyl, neopentyl, n-hexyl, n-heptyl, and n-octyl groups.

[0026] Examples of unsubstituted or substituted cycloalkyl groups include cycloalkyl groups having 3 to 10 carbon atoms, such as cyclobutyl, cyclopentyl, cyclohexyl, and cycloheptyl groups.

[0027] Examples of unsubstituted or substituted alkenyl groups include C2 to C10 alkenyl groups such as vinyl, 1-propenyl, 2-propenyl, 1-butenyl, 2-butenyl, and 3-butenyl groups.

[0028] Examples of substituents on the alkyl, cycloalkyl, and alkenyl groups include halogen atoms such as fluorine, chlorine, bromine, and iodine atoms; hydroxyl groups; thiol groups; epoxy groups; glycidoxy groups; (meth)acryloyloxy groups; and unsubstituted or substituted aryl groups such as phenyl groups, 4-methylphenyl groups, and 4-chlorophenyl groups.

[0029] Examples of unsubstituted or substituted aryl groups include aryl groups having 6 to 10 carbon atoms, such as phenyl, 1-naphthyl, and 2-naphthyl groups.

[0030] The lower limit of the number percentage of aryl groups in Rx, Ry, and Rz (organic groups) can be 20% or more in one embodiment, 50% or more in another embodiment, 70% or more in yet another embodiment, and 90% or more in yet another embodiment. This makes it easier to obtain cured products with excellent curability and light resistance, and also makes it easier to obtain cured products with a high refractive index, making them easier to use in equipment where a high refractive index is required. The upper limit of the number percentage of aryl groups in the organic group is not particularly limited, but in one embodiment it can be 100% or less. The range of the number percentage of aryl groups can be 20% or more and 100% or less in one embodiment, 50% or more and 100% or less in another embodiment, 70% or more and 100% or less in yet another embodiment, and 90% or more and 100% or less in yet another embodiment.

[0031] Examples of substituents on the aryl group include halogen atoms such as fluorine, chlorine, bromine, and iodine; C1 to C6 alkyl groups such as methyl and ethyl groups; C1 to C6 alkoxy groups such as methoxy and ethoxy groups; nitro groups; cyano groups; hydroxyl groups; thiol groups; epoxy groups; glycidoxy groups; (meth)acryloyloxy groups; and unsubstituted or substituted aryl groups such as phenyl, 4-methylphenyl, and 4-chlorophenyl groups.

[0032] Examples of alkylsilyl groups include trimethylsilyl group, triethylsilyl group, triisopropylsilyl group, tri-t-butylsilyl group, methyldiethylsilyl group, dimethylsilyl group, diethylsilyl group, methylsilyl group, and ethylsilyl group.

[0033] Among these, Rx, Ry, and Rz can be a hydrogen atom, an unsubstituted or substituted alkyl group having 1 to 6 carbon atoms, or a phenyl group, with the phenyl group being an example.

[0034] Furthermore, Rx, Ry, and Rz can be fluoro groups, which are substituents containing a fluorine atom. Examples of fluoro groups include fluoroalkyl groups, fluorocycloalkyl groups, fluoroalkenyl groups, and fluoroaryl groups. The fluoro group may or may not contain a hydrogen atom.

[0035] The lower limit of the number percentage of fluoro groups in Rx, Ry, and Rz (organic groups) can be 10% or more in one embodiment, 20% or more in another embodiment, 30% or more in yet another embodiment, and 40% or more in yet another embodiment. This makes it easier to obtain excellent curability and light resistance. The upper limit of the number percentage of fluoro groups in the organic groups is not particularly limited, but can be 90% or less in one embodiment, 80% or less in another embodiment, 70% or less in yet another embodiment, and 60% or less in yet another embodiment. This makes it easier to produce a more stable curable organopolysiloxane compound (A), to produce a liquid curable composition with stable performance, and to obtain a layer of curable composition that gives a cured product with excellent adhesion.

[0036] The curable organopolysiloxane compound (A) can be obtained, for example, by a known production method involving polycondensation of a silane compound having a hydrolyzable functional group (alkoxy group, halogen atom, etc.).

[0037] The silane compound used can be appropriately selected depending on the structure of the target curable organopolysiloxane compound (A). Examples include: bifunctional silane compounds such as dimethyldimethoxysilane, dimethyldiethoxysilane, diethyldimethoxysilane, and diethyldiethoxysilane; trifunctional silane compounds such as methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, n-propyltrimethoxysilane, n-butyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, and phenyldiethoxymethoxysilane; and tetrafunctional silane compounds such as tetramethoxysilane, tetraethoxysilane, tetran-propoxysilane, tetraisopropoxysilane, tetran-butoxysilane, tetrat-butoxysilane, tetras-butoxysilane, methoxytriethoxysilane, dimethoxydiethoxysilane, and trimethoxyethoxysilane.

[0038] The mass-average molecular weight (Mw) of the curable organopolysiloxane compound (A) can be 400 or more in one embodiment, 600 or more in another embodiment, 800 or more in yet another embodiment, 1,000 or more in yet another embodiment, 30,000 or less in one embodiment, 10,000 or less in another embodiment, 8,000 or less in yet another embodiment, 6,000 or less in yet another embodiment, and 4,000 or less in yet another embodiment. Furthermore, the range of the mass-average molecular weight (Mw) of the curable organopolysiloxane compound (A) can be 400 to 30,000 in one embodiment, 600 to 10,000 in another embodiment, 800 to 8,000 in yet another embodiment, 1,000 to 6,000 in yet another embodiment, and 1,000 to 4,000 in yet another embodiment. By using a curable organopolysiloxane compound (A) whose mass-average molecular weight (Mw) is within the above range, it becomes easier to obtain a layer of curable composition that provides excellent curability and light resistance, as well as a cured product with superior adhesion.

[0039] The molecular weight distribution (Mw / Mn) of the curable organopolysiloxane compound (A) is not particularly limited, but in one embodiment it can be 1.0 or more, in another embodiment it can be 1.1 or more, in one embodiment it can be 10.0 or less, and in another embodiment it can be 6.0 or less. Furthermore, the range of the molecular weight distribution (Mw / Mn) of the curable organopolysiloxane compound (A) can be 1.0 or more and 10.0 or less in one embodiment, and 1.1 or more and 6.0 or less in another embodiment. By using a curable organopolysiloxane compound (A) with a molecular weight distribution (Mw / Mn) within the above range, it becomes easier to obtain a layer of curable composition that provides excellent curability and light resistance, as well as a cured product with superior adhesion.

[0040] The mass-average molecular weight (Mw) and number-average molecular weight (Mn) of the curable organopolysiloxane compound (A) can be determined, for example, as standard polystyrene equivalent values ​​obtained by gel permeation chromatography (GPC) using tetrahydrofuran (THF) as the solvent.

[0041] The content of the curable organopolysiloxane compound (A) is not particularly limited, but the amount can be 40 parts by mass or more in one embodiment, 60 parts by mass or more in another embodiment, 70 parts by mass or more in yet another embodiment, per 100 parts by mass of the solid content (i.e., active ingredient) of the liquid curable composition, and can be less than 98 parts by mass in one embodiment, less than 94 parts by mass in another embodiment, and less than 90 parts by mass in yet another embodiment. The range of the amount of component (A) can be 40 parts by mass or more and less than 98 parts by mass in one embodiment, 60 parts by mass or more and less than 94 parts by mass in another embodiment, and 70 parts by mass or more and less than 90 parts by mass in yet another embodiment, per 100 parts by mass of the solid content of the liquid curable composition. By using component (A) within the above range, the effect of adding component (A) can be more strongly expressed.

[0042] Polysilsesquioxane compounds In one embodiment, the curable organopolysiloxane compound (A) can be a polysilsesquioxane compound obtained by polycondensation of a trifunctional organosilane compound. When a liquid curable composition contains a polysilsesquioxane compound as component (A), it is easier to obtain a layer of the curable composition that provides excellent curability and light resistance, as well as a cured product with superior toughness and adhesion.

[0043] The polysilsesquioxane compound can be a compound having repeating units represented by the following formula (a-4). When a liquid curable composition contains a polysilsesquioxane compound having repeating units represented by the following formula (a-4) as component (A), it becomes easier to obtain a layer of the curable composition that provides excellent curability and light resistance, as well as a cured product with superior toughness and adhesion.

[0044] [ka]

[0045] In formula (a-4), R 1 The symbol represents an organic group. The organic group can be selected from the group consisting of unsubstituted alkyl groups, substituted alkyl groups, unsubstituted cycloalkyl groups, substituted cycloalkyl groups, unsubstituted alkenyl groups, substituted alkenyl groups, unsubstituted aryl groups, substituted aryl groups, and alkylsilyl groups. For example, it can be selected from the group consisting of unsubstituted C1 to C10 alkyl groups, substituted C1 to C10 alkyl groups, unsubstituted C6 to C12 aryl groups, and substituted C6 to C12 aryl groups.

[0046] Examples of "unsubstituted C1 to C10 alkyl groups" include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, s-butyl group, t-butyl group, n-pentyl group, n-hexyl group, n-octyl group, n-nonyl group, and n-decyl group. 1 The number of carbon atoms in the "unsubstituted alkyl group having 1 to 10 carbon atoms" represented by can be 1 to 6 in one embodiment, and 1 to 3 in another embodiment.

[0047] R 1The number of carbon atoms in the "alkyl group having 1 to 10 carbon atoms with substituents" represented by can be 1 to 6 in one embodiment, and 1 to 3 in another embodiment. Note that this number of carbon atoms refers to the number of carbon atoms in the part excluding the substituent (the alkyl group part). Therefore, R 1 If R is a "carbon 1 to carbon 10 alkyl group having substituents", 1 The number of carbon atoms may exceed 10. Examples of alkyl groups in "substituted alkyl groups having 1 to 10 carbon atoms" are the same as those listed as "unsubstituted alkyl groups having 1 to 10 carbon atoms."

[0048] Examples of substituents in the "substituted C1 to C10 alkyl group" include halogen atoms such as fluorine, chlorine, and bromine atoms; cyano groups; groups represented by the formula OG; and the like. The number of atoms in the substituent of the "substituted C1 to C10 alkyl group" (excluding the number of hydrogen atoms) can be 1 to 30 in one embodiment and 1 to 20 in another embodiment. Here, G represents a hydroxyl group protecting group. There are no particular restrictions on the hydroxyl group protecting group, and known protecting groups known as hydroxyl group protecting groups can be used. Examples include acyl groups; silyl groups such as trimethylsilyl group, triethylsilyl group, t-butyldimethylsilyl group, and t-butyldiphenylsilyl group; acetal groups such as methoxymethyl group, methoxyethoxymethyl group, 1-ethoxyethyl group, tetrahydropyran-2-yl group, and tetrahydrofuran-2-yl group; alkoxycarbonyl groups such as t-butoxycarbonyl group; and ether groups such as methyl group, ethyl group, t-butyl group, octyl group, allyl group, triphenylmethyl group, benzyl group, p-methoxybenzyl group, fluorenyl group, trityl group, and benzhydryl group.

[0049] Examples of "unsubstituted aryl groups having 6 to 12 carbon atoms" include the phenyl group, 1-naphthyl group, and 2-naphthyl group. 1 The number of carbon atoms in the "unsubstituted aryl group with 6 to 12 carbon atoms" represented by can be 6.

[0050] R1 The number of carbon atoms of the "aryl group having 6 to 12 carbon atoms with a substituent" represented by can be 6. This number of carbon atoms means the number of carbon atoms in the part excluding the substituent (the aryl group part). Therefore, R 1 when is the "aryl group having 6 to 12 carbon atoms with a substituent", R 1 may have more than 12 carbon atoms. Examples of the aryl group of the "aryl group having 6 to 12 carbon atoms with a substituent" include the same ones as those shown as the "unsubstituted aryl group having 6 to 12 carbon atoms".

[0051] Examples of the substituent of the "aryl group having 6 to 12 carbon atoms with a substituent" include alkyl groups such as methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, s-butyl group, isobutyl group, t-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, isooctyl group; halogen atoms such as fluorine atom, chlorine atom, bromine atom; alkoxy groups such as methoxy group, ethoxy group; etc. The number of atoms of the substituent of the "aryl group having 6 to 12 carbon atoms with a substituent" (excluding the number of hydrogen atoms) can be 1 to 30 in one embodiment and 1 to 20 in another embodiment.

[0052] Among these, R 1 can be at least one selected from the group consisting of an unsubstituted alkyl group having 1 to 10 carbon atoms, an alkyl group having 1 to 10 carbon atoms having a fluorine atom, and an unsubstituted aryl group having 6 to 12 carbon atoms from the viewpoint that a polysilsesquioxane compound with a stable structure is easily obtained and the performance as a liquid curable composition is more stable. When a polysilsesquioxane compound in which R 1 is an unsubstituted alkyl group having 1 to 10 carbon atoms is used, it is easy to provide excellent curability and light resistance, and it is easy to obtain a layer of a curable composition that gives a cured product with more excellent toughness and adhesiveness.

[0053] Also, among these, R 1This makes it easier to efficiently obtain curable polysilsesquioxane compounds with a high refractive index, and makes them easier to use in equipment where a high refractive index is required. Therefore, it can be at least one selected from the group consisting of unsubstituted aryl groups having 6 to 12 carbon atoms and substituted aryl groups having 6 to 12 carbon atoms. For example, R 1 This can be a phenyl group.

[0054] Furthermore, polysilsesquioxane compounds are a type of R 1 It may also be a homopolymer having two or more R 1 It may also be a copolymer having [a specific characteristic].

[0055] The content of the repeating units represented by formula (a-4) in the polysilsesquioxane compound (i.e., the T-sites described later) can be 50 mol% or more in one embodiment, 70 mol% or more in another embodiment, and 90 mol% or more in yet another embodiment, relative to the total number of repeating units. Furthermore, the range of the content of the repeating units represented by formula (a-4) in the polysilsesquioxane compound (i.e., the T-sites described later) can be 50 to 100 mol% in one embodiment, 70 to 100 mol% in another embodiment, and 90 to 100 mol% in yet another embodiment, relative to the total number of repeating units. As an example, the content of the repeating units represented by formula (a-4) in the polysilsesquioxane compound (i.e., the T-sites described later) can be 100 mol%. By using a polysilsesquioxane compound with the above-mentioned content of the repeating units (T-sites) represented by formula (a-4), it becomes easier to obtain a layer of curable composition that provides a cured product with excellent light resistance. The proportion of repeating units (T sites) represented by formula (a-4) in a polysilsesquioxane compound is, for example, when NMR peak assignment and area integration are possible, 29 Si-NMR and 1 This can be determined by measuring H-NMR.

[0056] Polysilsesquioxane compounds are soluble in various organic solvents, including ketone solvents such as acetone; aromatic hydrocarbon solvents such as benzene; sulfur-containing solvents such as dimethyl sulfoxide; ether solvents such as tetrahydrofuran; ester solvents such as ethyl acetate; halogen-containing solvents such as chloroform; and mixed solvents consisting of two or more of these. Therefore, using these solvents, polysilsesquioxane compounds can be analyzed in solution. 29 Si-NMR and 1 H-NMR can be measured.

[0057] The repeating unit shown in formula (a-4) above may be the one shown in formula (a-5) below.

[0058] [ka]

[0059] As shown in formula (a-5), polysilsesquioxane compounds generally have a T site, which is a silicon atom bonded to three oxygen atoms, and other groups (R 1 It has a substructure formed by the combination of one of the following.

[0060] In formula (a-5), R 1 R in the above formula (a-4) is 1 This has the same meaning as *. * represents a Si atom, a hydrogen atom, or an alkyl group having 1 to 10 carbon atoms, and at least one of the three * is a Si atom. Examples of alkyl groups having 1 to 10 carbon atoms include methyl, ethyl, n-propyl, isopropyl, n-butyl, s-butyl, isobutyl, and t-butyl groups. Multiple *s may all be the same or different.

[0061] Furthermore, polysilsesquioxane compounds are thermosetting compounds that can undergo condensation reactions and / or hydrolysis upon heating. Therefore, at least one of the * in formula (a-5) of the multiple repeating units (T sites) of the polysilsesquioxane compound can be a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and a hydrogen atom can be used as an example.

[0062] Furthermore, if the polysilsesquioxane compound is soluble in the solvent used for measurement, 29 By measuring Si-NMR, it is possible to confirm the presence of hydrogen atoms or alkyl groups having 1 to 10 carbon atoms in the * in formula (a-5), and whether the three * in formula (a-5) are all Si atoms in a repeating unit. Furthermore, 29 If Si-NMR peak assignment and area integration are possible, the total number of repeating units in formula (a-5) where all three * are Si atoms can be estimated relative to the total number of repeating units (T sites) represented by formula (a-4) in the polysilsesquioxane compound. From the viewpoint of easily obtaining a layer of curable composition that gives stable productivity and stable performance, the total number of repeating units in formula (a-5) where all three * are Si atoms relative to the total number of repeating units (T sites) represented by formula (a-4) in the polysilsesquioxane compound can be 30 mol% or more in one embodiment, 40 mol% or more in another embodiment, 95 mol% or less in one embodiment, and 90 mol% or less in another embodiment. The range of the total number of repeating units in formula (a-5) where all three * are Si atoms relative to the total number of repeating units (T sites) represented by formula (a-4) in the polysilsesquioxane compound can be 30 to 95 mol% in one embodiment, and 40 to 90 mol% in another embodiment.

[0063] When the polysilsesquioxane compound is a copolymer, it may be a random copolymer, block copolymer, graft copolymer, alternating copolymer, etc., but from the viewpoint of ease of manufacture, it can be a random copolymer. Furthermore, the structure of the polysilsesquioxane compound may be a ladder structure, double-decker structure, cage structure, partially cleaved cage structure, cyclic structure, or random structure.

[0064] Furthermore, the polysilsesquioxane compound may be solid at room temperature, but it can also be liquid. Liquid refers to a state in which it has fluidity, for example, a state in which the viscosity is 10,000 Pa·s or less at room temperature, and room temperature is defined as 23°C. Using a liquid polysilsesquioxane compound allows for a reduction in the amount of solvent in the liquid curable composition, and allows for a higher concentration of the polysilsesquioxane compound in the liquid curable composition.

[0065] Polysilsesquioxane compounds can be used individually or in combination of two or more.

[0066] The method for producing polysilsesquioxane compounds is not particularly limited. For example, the following formula (a-6)

[0067] [ka]

[0068] (In the formula, R 1 R in the above formula (a-4) is 1 It expresses the same meaning as R. 2 X represents an alkyl group having 1 to 10 carbon atoms. 1 R represents a halogen atom, and p represents an integer from 0 to 3. Multiple R 2 , and multiple X 1 These may be identical or different from each other. A polysilsesquioxane compound can be produced by polycondensing at least one of the silane compounds (1) represented by ). 2Examples of C1 to C10 alkyl groups include those similar to those shown as C1 to C10 alkyl groups in formula (a-5) above. 1 Examples of halogen atoms include chlorine atoms and bromine atoms.

[0069] Specific examples of silane compounds (1) include alkyltrialalkoxysilane compounds such as methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, and ethyltripropoxysilane; and alkylhalogenoloxysilane compounds such as methylchlorodimethoxysilane, methylchlorodiethoxysilane, methyldichloromethoxysilane, methylbromodimethoxysilane, ethylchlorodimethoxysilane, ethylchlorodiethoxysilane, ethyldichloromethoxysilane, and ethylbromodimethoxysilane. Substances; alkyltrihalogenosilane compounds such as methyltrichlorosilane, methyltribromosilane, ethyltrichlorosilane, and ethyltribromosilane; substituted alkyltrialkoxysilane compounds such as 3,3,3-trifluoropropyltrimethoxysilane, 3,3,3-trifluoropropyltriethoxysilane, 2-cyanoethyltrimethoxysilane, and 2-cyanoethyltriethoxysilane; 3,3,3-trifluoropropylchlorodimethoxysilane, 3,3,3-trifluoropropylchlorodiethoxysilane, and 3,3,3- Substituted alkylhalogenoalkoxysilane compounds such as difluoropropyldichloromethoxysilane, 3,3,3-trifluoropropyldichloroethoxysilane, 2-cyanoethylchlorodimethoxysilane, 2-cyanoethylchlorodiethoxysilane, 2-cyanoethyldichloromethoxysilane, and 2-cyanoethyldichloroethoxysilane; Substituted alkyltrihalogenosilane compounds such as 3,3,3-trifluoropropyltrichlorosilane and 2-cyanoethyltrichlorosilane; Phenyltrimethoxysilane, 4-methoxyphenyltrimethyl Examples include phenyltrialkoxysilane compounds with or without substituents, such as toxicilane; phenylhalogenoalkoxysilane compounds with or without substituents, such as phenylchlorodimethoxysilane, phenyldichloromethoxysilane, 4-methoxyphenylchlorodimethoxysilane, and 4-methoxyphenyldichloromethoxysilane; and phenyltrihalogenosilane compounds with or without substituents, such as phenyltrichlorosilane and 4-methoxyphenyltrichlorosilane.These silane compounds (1) can be used individually or in combination of two or more.

[0070] The method for polycondensing the silane compound (1) is not particularly limited. For example, one method involves adding a predetermined amount of polycondensation catalyst to the silane compound (1) in a solvent or without a solvent and stirring at a predetermined temperature. Specifically, examples include (a) adding a predetermined amount of acid catalyst to the silane compound (1) and stirring at a predetermined temperature, (b) adding a predetermined amount of base catalyst to the silane compound (1) and stirring at a predetermined temperature, and (c) adding a predetermined amount of acid catalyst to the silane compound (1), stirring at a predetermined temperature, then adding an excess amount of base catalyst to make the reaction system basic, and stirring at a predetermined temperature. Among these, polycondensation can be performed by method (a) or (c) because it is possible to efficiently obtain the desired polysilsesquioxane compound.

[0071] The polycondensation catalyst used may be either an acid catalyst or a base catalyst. Furthermore, two or more polycondensation catalysts may be used in combination, and at least one acid catalyst may be used. Examples of acid catalysts include inorganic acids such as phosphoric acid, hydrochloric acid, boric acid, sulfuric acid, and nitric acid; and organic acids such as citric acid, acetic acid, methanesulfonic acid, trifluoromethanesulfonic acid, benzenesulfonic acid, and p-toluenesulfonic acid. Among these, at least one selected from phosphoric acid, hydrochloric acid, boric acid, sulfuric acid, citric acid, acetic acid, and methanesulfonic acid may be used.

[0072] Examples of base catalysts include aqueous ammonia; organic bases such as trimethylamine, triethylamine, lithium diisopropylamide, lithium bis(trimethylsilyl)amide, pyridine, 1,8-diazabicyclo[5.4.0]-7-undecene, aniline, picoline, 1,4-diazabicyclo[2.2.2]octane, and imidazole; organic salt hydroxides such as tetramethylammonium hydroxide and tetraethylammonium hydroxide; metal alkoxides such as sodium methoxide, sodium ethoxide, sodium t-butoxide, and potassium t-butoxide; metal hydrides such as sodium hydride and calcium hydride; metal hydroxides such as sodium hydroxide, potassium hydroxide, and calcium hydroxide; metal carbonates such as sodium carbonate, potassium carbonate, and magnesium carbonate; and metal bicarbonates such as sodium bicarbonate and potassium bicarbonate.

[0073] The amount of polycondensation catalyst used can be 0.05 mol% or more in one embodiment, 0.1 mol% or more in another embodiment, 10 mol% or less in one embodiment, and 5 mol% or less in another embodiment, relative to the total molar amount of silane compound (1). The range of the amount of polycondensation catalyst used can be 0.05 to 10 mol% in one embodiment, and 0.1 to 5 mol% in another embodiment, relative to the total molar amount of silane compound (1).

[0074] When a solvent is used during polycondensation, the solvent can be appropriately selected depending on the type of silane compound (1), etc. Examples include water; aromatic hydrocarbons such as benzene, toluene, and xylene; esters such as methyl acetate, ethyl acetate, propyl acetate, butyl acetate, and methyl propionate; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; and alcohols such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, s-butyl alcohol, and t-butyl alcohol. These solvents can be used individually or in combination of two or more. Furthermore, when employing the method described in (c) above, the polycondensation reaction may be carried out in an aqueous system in the presence of an acid catalyst, and then an organic solvent and a base catalyst (such as aqueous ammonia) may be added to the reaction solution, and the polycondensation reaction may be carried out again under neutral or basic conditions.

[0075] The amount of solvent used can be 0.001 liters or more per 1 mole of total silane compound (1) in one embodiment, 0.01 liters or more in another embodiment, and 10 liters or less in one embodiment, and 0.9 liters or less in another embodiment. The range of solvent used can be 0.001 liters or more and 10 liters or less in one embodiment, and 0.01 liters or more and 0.9 liters or less in another embodiment, per 1 mole of total silane compound (1).

[0076] The temperature used for polycondensation of silane compound (1) is typically within the range from 0°C to the boiling point of the solvent used. In one embodiment, it can be 20°C or higher, in another embodiment, 30°C or higher, and in one embodiment, 100°C or lower, in another embodiment, 95°C or lower. The temperature range for polycondensation of silane compound (1) can be 20°C to 100°C in one embodiment, and 30°C to 95°C in another embodiment. Setting the temperature above this lower limit ensures sufficient progress of the polycondensation reaction. On the other hand, setting the temperature below this upper limit suppresses gelation. The reaction is completed in 30 minutes to 30 hours.

[0077] Furthermore, depending on the type of monomer used, it may be difficult to achieve high molecular weight. For example, R 1 A monomer in which is an alkyl group having a fluorine atom is R 1 These monomers tend to be less reactive than monomers with typical alkyl groups. In such cases, reducing the amount of catalyst and carrying out the reaction for a long time under mild conditions makes it easier to obtain the polysilsesquioxane compound with the desired molecular weight.

[0078] After the reaction is complete, if an acid catalyst is used, the reaction solution is neutralized by adding an alkaline aqueous solution such as sodium bicarbonate. If a base catalyst is used, the reaction solution is neutralized by adding an acid such as hydrochloric acid. The salt produced at this time is then removed by filtration or washing with water to obtain the desired polysilsesquioxane compound.

[0079] When producing a polysilsesquioxane compound by the above method, the OR of silane compound (1) 2 or X 1 Of these, the portion that did not undergo hydrolysis and subsequent condensation reactions remains in the polysilsesquioxane compound.

[0080] If component (A) is, for example, a polysilsesquioxane compound obtained by the polycondensation reaction of silane compound (1), then curing proceeds by a condensation reaction, including the reaction with the silane coupling agent described later. Therefore, the liquid curable composition of this embodiment is different from a general heat-curable silicone adhesive or heat-curable silicone component that cures by an addition reaction in the presence of a precious metal catalyst such as a platinum catalyst. Accordingly, the liquid curable composition containing the polysilsesquioxane compound substantially does not contain a precious metal catalyst, or contains a small amount of a precious metal catalyst. Here, "substantially does not contain a precious metal catalyst" means that "components that can be interpreted as a precious metal catalyst are not intentionally added, and the content of the precious metal catalyst relative to the amount of active ingredients in the liquid curable composition is, for example, less than 1 ppm by mass in terms of the mass of the catalyst metal element." Here, "active ingredients" refers to "components contained in the liquid curable composition excluding the solvent (S) (described later)." Liquid curable compositions may contain substantially no precious metal catalysts or have a low content of precious metal catalysts, considering factors such as stable manufacturing with regard to variations in formulation, long-term static stability, and the high cost of precious metal catalysts.

[0081] The liquid curable composition of this embodiment contains a curable organopolysiloxane compound (A), but may also contain the following components.

[0082] (Silane coupling agent (B)) The liquid curable composition of this embodiment contains a silane coupling agent (B) (hereinafter sometimes referred to as "component (B)"). By including the silane coupling agent (B), the composition exhibits excellent workability in the coating process and excellent curability due to a condensation reaction with component (A) when heated. The silane coupling agent (B) contains a silane coupling agent (B) having two or more alkoxysilyl groups or silanol groups in its molecule. This makes it easier to provide toughness to the cured product, which is formed by coating the liquid curable composition onto a sheet-like substrate, drying it to form a layer of curable composition, and curing it, in order to stably maintain the shape of the cured product. Furthermore, when the cured product is cut to produce individual pieces of cured product, cracking of the cured product is suppressed.

[0083] The silane coupling agent (B) is not particularly limited as long as it is a silane coupling agent having two or more alkoxysilyl groups or silanol groups in its molecule. Examples include trialkoxysilane compounds represented by formula (b-1) below, dialkoxyalkylsilane compounds represented by formula (b-2) or dialkoxyarylsilane compounds.

[0084] [ka] JPEG2026059355000008.jpg1266

[0085] In the above formula, R a R represents alkoxy groups with 1 to 6 carbon atoms, such as methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, and t-butoxy groups. a The individuals may be identical or different. b This represents an alkyl group having 1 to 6 carbon atoms, such as a methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, or t-butyl group; or an aryl group with or without substituents, such as a phenyl group, 4-chlorophenyl group, 4-methylphenyl group, or 1-naphthyl group.

[0086] R cR represents an organic group having 1 to 10 carbon atoms and containing a nitrogen atom. c It may also be bonded to other groups containing silicon atoms. c Specific examples of organic groups having 1 to 10 carbon atoms include N-2-(aminoethyl)-3-aminopropyl group, 3-aminopropyl group, N-(1,3-dimethylbutylidene)aminopropyl group, 3-ureidopropyl group, and N-phenyl-aminopropyl group.

[0087] Among the compounds represented by the above formula (b-1) or (b-2), R c However, examples of compounds in which the organic group is bonded to a group containing other silicon atoms include those that bond to other silicon atoms via an isocyanurate skeleton to form an isocyanurate-based silane coupling agent, and those that bond to other silicon atoms via a urea skeleton to form a urea-based silane coupling agent.

[0088] Among these, silane coupling agent (B) can be an isocyanurate-based silane coupling agent or a urea-based silane coupling agent, as it is easier to obtain a hardened product in which cracks are suppressed during cleavage. Furthermore, it can have four or more alkoxy groups bonded to silicon atoms in its molecule. Having four or more alkoxy groups bonded to silicon atoms means that the total number of alkoxy groups bonded to the same silicon atom and alkoxy groups bonded to different silicon atoms is four or more.

[0089] Examples of isocyanurate-based silane coupling agents having four or more alkoxy groups bonded to a silicon atom include the compound represented by the following formula (b-3), and examples of urea-based silane coupling agents having four or more alkoxy groups bonded to a silicon atom include the compound represented by the following formula (b-4).

[0090] [ka] JPEG2026059355000010.jpg26131

[0091] In the formula, R a R in the above formulas (b-1) and (b-2) is a This expresses the same meaning. t1 through t5 each independently represent integers from 1 to 10, and can be integers from 1 to 6, for example, 3.

[0092] Specific examples of compounds represented by formula (b-3) include 1,3,5-N-tris(3-trimethoxysilylpropyl)isocyanurate, 1,3,5-N-tris(3-triethoxysilylpropyl)isocyanurate, 1,3,5-N-tris(3-tri-i-propoxysilylpropyl)isocyanurate, 1,3,5-N-tris(3-tributoxysilylpropyl)isocyanurate, and other 1,3,5-N-tris[(tri(carbon 1 to 6)alkoxy)silyl(carbon 1 to 10)alkyl]isocyanurate compounds;1,3,5-N-Tris(3-dimethoxymethylsilylpropyl) isocyanurate, 1,3,5-N-Tris(3-dimethoxyethylsilylpropyl) isocyanurate, 1,3,5-N-Tris(3-dimethoxyi-propylsilylpropyl) isocyanurate, 1,3,5-N-Tris(3-dimethoxyn-propylsilylpropyl) isocyanurate, 1,3,5-N-Tris(3-dimethoxyphenylsilylpropyl) isocyanurate, 1,3,5-N-Tris(3-diethylmethylsilylpropyl) Isocyanurate (1,3,5-N-Tris(3-diethoxyethylsilylpropyl) isocyanurate), 1,3,5-N-Tris(3-diethoxyi-propylsilylpropyl) isocyanurate, 1,3,5-N-Tris(3-diethoxyn-propylsilylpropyl) isocyanurate, 1,3,5-N-Tris(3-diethoxyphenylsilylpropyl) isocyanurate, 1,3,5-N-Tris(3-di-i-propoxymethylsilylpropyl) isocyanurate 1,3,5-N-Tris(3-di-i-propoxyethylsilylpropyl) isocyanurate, 1,3,5-N-Tris(3-di-i-propoxy-i-propylsilylpropyl) isocyanurate, 1,3,5-N-Tris(3-di-i-propoxy-n-propylsilylpropyl) isocyanurate, 1,3,5-N-Tris(3-di-i-propoxyphenylsilylpropyl) isocyanurate, 1,3,5-N-Tris(3-dibutoxymethylsilylpropyl) isocyanurate, 1,3,5- Examples include 1,3,5-N-tris[(di(C1 to C6)alkoxy)silyl(C1 to C10)alkyl]isocyanurates such as N-tris(3-dibutoxyethylsilylpropyl)isocyanurate, 1,3,5-N-tris(3-dibutoxyi-propylsilylpropyl)isocyanurate, 1,3,5-N-tris(3-dibutoxyphenylsilylpropyl)isocyanurate, etc.

[0093] Specific examples of compounds represented by formula (b-4) include N,N'-bis(3-trimethoxysilylpropyl)urea, N,N'-bis(3-triethoxysilylpropyl)urea, N,N'-bis(3-tripropoxysilylpropyl)urea, N,N'-bis(3-tributoxysilylpropyl)urea, N,N'-bis(2-trimethoxysilylethyl)urea, and other N,N'-bis[(tri(carbon 1 to 6)alkoxysilyl)(carbon 1 to 10)alkyl]urea; N,N'-bis(3-dimethoxymethylsilylpropyl)urea, N,N' Examples include N,N'-bis[(di(carbon 1 to 6)alkoxy(carbon 1 to 6)alkylsilyl(carbon 1 to 10)alkyl)ureas such as -bis(3-dimethoxyethylsilylpropyl)urea and N,N'-bis(3-diethoxyphenylsilylpropyl)urea; and N,N'-bis[(di(carbon 1 to 6)alkoxy(carbon 6 to 20)arylsilyl(carbon 1 to 10)alkyl)ureas such as N,N'-bis(3-dimethoxyphenylsilylpropyl)urea and N,N'-bis(3-diethoxyphenylsilylpropyl)urea. The silane coupling agent (B) can be used alone or in combination of two or more.

[0094] Among these, the silane coupling agent (B) can be 1,3,5-N-tris(3-trimethoxysilylpropyl) isocyanurate, 1,3,5-N-tris(3-triethoxysilylpropyl) isocyanurate (hereinafter, the two are referred to as "isocyanurate compounds"), N,N'-bis(3-trimethoxysilylpropyl) urea, N,N'-bis(3-triethoxysilylpropyl) urea (hereinafter, the two are referred to as "urea compounds"), or a combination of the above isocyanurate compounds and urea compounds.

[0095] The content of the silane coupling agent (B) in the liquid curable composition can be 12 parts by mass or more in one embodiment, 16 parts by mass or more in another embodiment, and 20 parts by mass or more in yet another embodiment, per 100 parts by mass of the solid content (i.e., active ingredient) of the liquid curable composition, and can be less than 50 parts by mass in one embodiment, less than 40 parts by mass in another embodiment, and less than 30 parts by mass in yet another embodiment, per 100 parts by mass of the solid content (i.e., active ingredient) of the liquid curable composition. The range of the amount of the silane coupling agent (B) can be 12 parts by mass or more and less than 50 parts by mass in one embodiment, 16 parts by mass or more and less than 40 parts by mass in another embodiment, and 20 parts by mass or more and less than 30 parts by mass in yet another embodiment, per 100 parts by mass of the solid content (i.e., active ingredient) of the liquid curable composition.

[0096] By using component (B) within the above range, the effect of adding component (B) can be more effectively realized, making it easier to obtain a cured product in which crack formation is suppressed when the cured product is cut.

[0097] (Thermal acid generator (C)) The liquid curable composition of this embodiment contains a thermal acid generator (C) (hereinafter sometimes referred to as "component (C)"). A thermal acid generator is a compound that generates acid components such as Lewis acids and Brønsted acids when heated. The liquid curable composition of this embodiment contains a thermal acid generator (C), which promotes the hydrolysis reaction and subsequent condensation reaction through the generation of acid, resulting in excellent curability and adhesion. On the other hand, compounds containing acid anhydrides improve the curability of the liquid curable composition. As described above, the liquid curable composition of this embodiment either keeps the amount of compounds containing acid anhydrides low or eliminates them entirely. However, by including a thermal acid generator, the liquid curable composition of this embodiment can compensate for the low amount of compounds containing acid anhydrides, thereby maintaining or improving the curability of the liquid curable composition and the toughness necessary to stably maintain the shape of the cured product.

[0098] In one embodiment, the thermoacid generator (C) can have a peak temperature (acid generation temperature) of the maximum endothermic peak obtained by differential scanning calorimetry under the conditions of a temperature range of 30 to 300°C and a heating rate of 10°C / min, which in one embodiment is 80°C or higher, in another embodiment is 90°C or higher, and in yet another embodiment is 100°C or higher. Including such a thermoacid generator improves the long-term static stability of the liquid curable composition. Furthermore, under the above conditions, the acid generation temperature of the thermoacid generator (C) can be 180°C or lower in one embodiment, 170°C or lower in another embodiment, and 160°C or lower in yet another embodiment. Including such a thermoacid generator improves the curability of the liquid curable composition. Furthermore, under the above conditions, the acid generation temperature range of the thermoacid generator (C) can be 80°C to 180°C in one embodiment, 90°C to 170°C in another embodiment, and 100°C to 160°C in yet another embodiment. The inclusion of such a thermal acid generator improves the long-term static stability and curability of the liquid curable composition.

[0099] In one embodiment, the thermal acid generator (C) can be an onium salt-based thermal acid generator or a block acid compound-based thermal acid generator. The onium salt-based thermal acid generator is a thermal acid generator containing an onium cation component and an anion component. Examples of the onium cation component include organic sulfonium ions, organic ammonium ions, organic phosphonium ions, and organic iodonium ions. Examples of organic sulfonium ions constituting the onium salt-based thermal acid generator include cations represented by the following formula (c-1).

[0100] [ka]

[0101] In formula (c-1), R 4 , R 5 , and R 6Each of these can be independently selected from the group consisting of unsubstituted C1 to C10 alkyl groups, substituted C1 to C10 alkyl groups, unsubstituted C6 to C12 aryl groups, and substituted C6 to C12 aryl groups.

[0102] R 4 From R 6 The number of carbon atoms in the "unsubstituted C1 to C10 alkyl group" represented by can be 1 to 6 in one embodiment, and 1 to 3 in another embodiment. Examples of the "unsubstituted C1 to C10 alkyl group" include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, s-butyl group, t-butyl group, n-pentyl group, n-hexyl group, n-octyl group, n-nonyl group, n-decyl group, etc.

[0103] R 4 From R 6 The number of carbon atoms in the "alkyl group having 1 to 10 carbon atoms with substituents" represented by can be 1 to 6 in one embodiment, and 1 to 3 in another embodiment. Note that this number of carbon atoms refers to the number of carbon atoms in the part excluding the substituent (the alkyl group part). Therefore, R 4 From R 6 If R is a "carbon 1 to carbon 10 alkyl group having substituents", 4 From R 6 The number of carbon atoms may exceed 10. Examples of alkyl groups in "substituted alkyl groups having 1 to 10 carbon atoms" are the same as those listed as "unsubstituted alkyl groups having 1 to 10 carbon atoms."

[0104] The number of substituent atoms (excluding hydrogen atoms) in the "substituted C1 to C10 alkyl group" can be 1 to 30 in one embodiment and 1 to 20 in another embodiment. Examples of substituents in the "substituted C1 to C10 alkyl group" include aryl groups such as phenyl, o-tolyl, m-tolyl, p-tolyl, 1-naphthyl, and 2-naphthyl groups.

[0105] R 4 From R 6 In one embodiment, the number of carbon atoms in the "unsubstituted aryl group having 6 to 12 carbon atoms" can be 6. Examples of the "unsubstituted aryl group having 6 to 12 carbon atoms" include the phenyl group, 1-naphthyl group, and 2-naphthyl group.

[0106] R 4 From R 6 The number of carbon atoms in the "substituted aryl group having 6 to 12 carbon atoms" represented by can be 6 in one embodiment. Note that this number of carbon atoms refers to the number of carbon atoms in the part excluding the substituent (the aryl group part). Therefore, R 4 From R 6 If R is a "substituted aryl group having 6 to 12 carbon atoms", 4 From R 6 The number of carbon atoms may exceed 12. Examples of aryl groups in "substituted aryl groups with 6 to 12 carbon atoms" are the same as those listed as "unsubstituted aryl groups with 6 to 12 carbon atoms."

[0107] The number of substituent atoms (excluding hydrogen atoms) in the "substituted C6 to C12 aryl group" can be 1 to 30 in one embodiment and 1 to 20 in another embodiment. Examples of substituents in the "substituted C6 to C12 aryl group" include alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, s-butyl, isobutyl, t-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, and isooctyl groups; alkoxy groups such as methoxy and ethoxy groups; hydroxyl groups; and acyloxy groups such as acetyloxy and propionyloxy groups.

[0108] Examples of organic ammonium ions that constitute onium salt-based thermal acid generators include cations represented by the following formula (c-2).

[0109] [ka]

[0110] In formula (c-2), R 7 , R 8 , R 9 , and R 10 Each of these groups is independently selected from the group consisting of unsubstituted C1 to C10 alkyl groups, substituted C1 to C10 alkyl groups, unsubstituted C6 to C12 aryl groups, and substituted C6 to C12 aryl groups. 7 From R 10 For example, R 4 From R 6 Examples similar to those expressed as above can be given.

[0111] Examples of organic phosphonium ions that constitute onium salt-based thermal acid generators include the cation represented by the following formula (c-3).

[0112] [ka]

[0113] In formula (c-3), R 11 , R 12 , R 13 , and R 14 Each of these groups is independently selected from the group consisting of unsubstituted C1 to C10 alkyl groups, substituted C1 to C10 alkyl groups, unsubstituted C6 to C12 aryl groups, and substituted C6 to C12 aryl groups. 11 From R 14 For example, R 4 From R 6 Examples similar to those expressed as above can be given.

[0114] Examples of organic iodonium ions that constitute onium salt-based thermal acid generators include the cation represented by the following formula (c-4).

[0115] [ka]

[0116] In formula (c-4), R 15 , and R 16 Each of these groups is independently selected from the group consisting of unsubstituted C1 to C10 alkyl groups, substituted C1 to C10 alkyl groups, unsubstituted C6 to C12 aryl groups, and substituted C6 to C12 aryl groups. 15 , and R 16 For example, R 4 From R 6 Examples similar to those expressed as above can be cited. Among these, the onium cation component can be an organic sulfonium ion or an organic ammonium ion, and the organic sulfonium ion represented by the following formula (c-5) is more preferred because it has an appropriate acid generation temperature from the viewpoint of achieving both the curability of the layer of the curable composition and the long-term static stability of the liquid curable composition, and the reactivity of the acid generation reaction can be easily controlled.

[0117] [ka]

[0118] In formula (c-5), Ar represents an aryl group having a substituent such as a phenyl group, an o-tolyl group, an m-tolyl group, a p-tolyl group, a 1-naphthyl group, or a 2-naphthyl group, or an unsubstituted aryl group.

[0119] Examples of anionic components of onium salt-based thermal acid generators include trifluoromethanesulfonate anion, hexafluorophosphate anion, hexafluoroantimonate anion, perfluorobutanesulfonate anion, tetrakis(pentafluorophenyl)borate anion, and tetrafluoroborate anion. In one embodiment, the anionic component can be hexafluorophosphate anion, hexafluoroantimonate anion, or tetrakis(pentafluorophenyl)borate anion.

[0120] Blocked acid compound-based thermal acid generators are compounds obtained by protecting (blocking) organic sulfonic acids, organic phosphoric acids, and organic carboxylic acids with amine compounds, ether compounds, etc. Examples include amine salts of p-toluenesulfonic acid, quaternary ammonium salts of p-toluenesulfonic acid, amine salts of trifluoromethanesulfonic acid, and quaternary ammonium salts of trifluoromethanesulfonic acid.

[0121] Specific examples of the thermal acid generator (C) include 2-methylbenzylmethyl p-hydroxyphenylsulfonium hexafluoroantimonate, 1-naphthylmethylmethyl p-hydroxyphenylsulfonium hexafluorophosphate, and (4-hydroxyphenyl)methyl(4-methylbenzyl)sulfonium tetrakis(pentafluorophenyl)borate, benzyl(4-hydroxyphenyl)methylsulfonium hexafluorophosphate, and amine-blocked compounds of p-toluenesulfonic acid.

[0122] In one embodiment, the thermal acid generator (C) can be used alone or in combination of two or more types.

[0123] The content of the thermal acid generator (C) can be, per 100 parts by mass of the curable organopolysiloxane compound (A), greater than 0 parts by mass in one embodiment, 0.001 parts by mass or more in another embodiment, 0.01 parts by mass or more in yet another embodiment, 0.1 parts by mass or more in yet another embodiment, 0.3 parts by mass or more in yet another embodiment, 5.0 parts by mass or less in one embodiment, 3.0 parts by mass or less in another embodiment, 2.0 parts by mass or less in yet another embodiment, 1.5 parts by mass or less in yet another embodiment, and 1.2 parts by mass or less in yet another embodiment. This makes it possible to obtain a product with excellent curability and adhesion.

[0124] Furthermore, the content range of the thermal acid generator (C) can be, in one embodiment, more than 0 parts by mass and 5.0 parts by mass or less per 100 parts by mass of the curable organopolysiloxane compound (A); in another embodiment, 0.001 parts by mass or more and 3.0 parts by mass or less; in yet another embodiment, 0.01 parts by mass or more and 2.0 parts by mass or less; in yet another embodiment, 0.1 parts by mass or more and 1.5 parts by mass or less; and in yet another embodiment, 0.3 parts by mass or more and 1.2 parts by mass or less.

[0125] (Solvent (S)) The liquid curable composition of this embodiment may contain a solvent (S). The solvent (S) is not particularly limited as long as it can dissolve or disperse the active ingredients of the liquid curable composition. The solvent (S) may include an organic solvent having a boiling point of 254°C or higher (hereinafter sometimes referred to as "organic solvent (SH)"). Here, "boiling point" means "boiling point at 1013 hPa".

[0126] The liquid curable composition may contain a solvent other than an organic solvent (SH). The solvent other than an organic solvent (SH) may be a solvent with a boiling point of 70°C or higher and less than 254°C (hereinafter sometimes referred to as "organic solvent (SL)"). The organic solvent (SL) is not particularly limited as long as it has a boiling point of 70°C or higher and less than 254°C and can dissolve or disperse the components of the liquid curable composition. In one embodiment, the organic solvent (SL) may have a boiling point of 70°C or higher and less than 200°C, and in another embodiment, the boiling point may be 70°C or higher and less than 170°C, which further suppresses the generation of bubbles (voids) in the cured product.

[0127] Specific examples of organic solvents (SL) include diethylene glycol monobutyl ether acetate (boiling point 247°C), dipropylene glycol-n-butyl ether (boiling point 229°C), dipropylene glycol methyl ether acetate (boiling point 209°C), diethylene glycol butyl methyl ether (boiling point 212°C), dipropylene glycol-n-propyl ether (boiling point 212°C), and tripropylene glycol dimethyl ether (boiling point 215°C). ), triethylene glycol dimethyl ether (boiling point 216°C), diethylene glycol monoethyl ether acetate (boiling point 218°C), diethylene glycol-n-butyl ether (boiling point 230°C), ethylene glycol monophenyl ether (boiling point 245°C), tripropylene glycol methyl ether (boiling point 242°C), propylene glycol phenyl ether (boiling point 243°C), triethylene glycol monomethyl ether (boiling point 249°C), benzyl alcohol (boiling point 204.9°C), phenethyl alcohol (boiling point 219 to 221°C), ethylene glycol monobutyl Examples include ether acetate (boiling point 192°C), ethylene glycol monoethyl ether (boiling point 134.8°C), ethylene glycol monomethyl ether (boiling point 124.5°C), propylene glycol monomethyl ether acetate (boiling point 146°C), cyclopentanone (boiling point 130°C), cyclohexanone (boiling point 157°C), cycloheptanone (boiling point 180°C), cyclooctanone (boiling point 195 to 197°C), cyclohexanol (boiling point 161°C), toluene (boiling point 111°C), cyclohexadienone (boiling point 104 to 104.5°C), and methyl ethyl ketone (boiling point 80°C). Among these, the organic solvent (SL) can be diethylene glycol monobutyl ether acetate, cyclohexanone, or methyl ethyl ketone, from the viewpoint of easy mixing of the active ingredient.

[0128] The liquid curable composition may contain an amount of solvent (S) such that the solid content (i.e., active ingredient) concentration is 70% by mass or more in one embodiment, 75% by mass or more in another embodiment, 80% by mass or more in yet another embodiment, and 85% by mass or more in yet another embodiment, and may contain an amount of solvent (S) such that the solid content concentration is less than 95% by mass in one embodiment and less than 90% by mass in another embodiment. The liquid curable composition may contain an amount of solvent (S) such that the solid content concentration ranges from 70% by mass or more to less than 95% by mass in one embodiment, and from 75% by mass or more to less than 90% by mass in another embodiment. This makes it easier to adjust the viscosity of the liquid curable composition and further suppresses the generation of air bubbles (voids) in the cured product.

[0129] Having a solid content concentration within this range makes it easier to mix the active ingredients and improves workability during the application process. Furthermore, although the liquid curable composition can be stored in containers such as 18-liter cans, pails, and drums, having a solid content concentration within this range makes it easier to fill the containers with the liquid curable composition.

[0130] (Fine particles (D)) The liquid curable composition of this embodiment may contain fine particles (D) (hereinafter sometimes referred to as "component (D)"). Furthermore, the fine particles (D) may include silica fine particles (D1) having an average primary particle diameter of 20 nm or less.

[0131] Silica microparticles (D1) By containing silica fine particles (D1), when applying a liquid curable composition to a sheet-like substrate, repelling (the phenomenon where the spread liquid gathers) and coating surface roughness are more suppressed, and the workability in the coating process is improved. The average primary particle diameter of the silica fine particles (D1) can be 20 nm or less in one embodiment, 15 nm or less in another embodiment, and 10 nm or less in yet another embodiment. Thereby, aggregation of the liquid curable composition is suppressed, and when applying the liquid curable composition to a sheet-like substrate, repelling and coating surface roughness are more suppressed, and the workability in the coating process is improved. Further, the average primary particle diameter of the silica fine particles (D1) can be 1 nm or more in one embodiment, 2 nm or more in another embodiment, and 5 nm or more in yet another embodiment. Thereby, aggregation of the silica fine particles that might occur as if large particles were used is suppressed, aggregation of the liquid curable composition is suppressed, and when applying the liquid curable composition to a sheet-like substrate, repelling and coating surface roughness are more suppressed, and the workability in the coating process is improved. Also, the range of the average primary particle diameter of the silica fine particles (D1) can be 1 nm or more and 20 nm or less in one embodiment, 2 nm or more and 15 nm or less in another embodiment, and 5 nm or more and 10 nm or less in yet another embodiment. The average primary particle diameter of the silica fine particles (D1) is obtained by randomly selecting 2000 silica fine particles (D1) using a transmission electron microscope to observe the primary particles and averaging the obtained 2000 particle diameter (nm) data. Note that the average value is calculated as an integer by rounding the first decimal place.

[0132] The specific surface area of the silica fine particles (D1) can be 100 m 2 / g or more in one embodiment, 200 m 2 / g or more in another embodiment, and 300 m 2 / g or more in yet another embodiment, and can be 2500 m 2 / g or less in one embodiment, 1000 m 2 / g or less in another embodiment, and 500 m 2It can be 100 m 2 / g or more and 2500 m 2 / g or less. In another embodiment, it can be 200 m 2 / g or more and 1000 m 2 / g or less. In yet another embodiment, it can be 300 m 2 / g or more and 500 m 2 / g or less.

[0133] The content of the silica fine particles (D1) can be 1 part by mass or more, in another embodiment 2 parts by mass or more, and in yet another embodiment 2.5 parts by mass or more with respect to 100 parts by mass of the liquid curable composition. In one embodiment, it can be less than 20 parts by mass, in another embodiment less than 12 parts by mass, and in yet another embodiment less than 8 parts by mass. The range of the amount of the silica fine particles (D1) can be 1 part by mass or more and less than 20 parts by mass, in another embodiment 2 parts by mass or more and less than 12 parts by mass, and in yet another embodiment 2.5 parts by mass or more and less than 8 parts by mass with respect to 100 parts by mass of the liquid curable composition. By using the silica fine particles (D1) within the above range, the effect of adding the silica fine particles (D1) can be more effectively exhibited.

[0134] The shape of the silica fine particles (D1) may be any of spherical, chain-like, needle-like, plate-like, flaky, rod-like, fibrous, etc., and can be spherical. Here, "spherical" means "including not only a true sphere but also a substantially spherical shape such as an ellipsoid of revolution, an oval shape, a sugar-loaf shape, a spindle shape, etc., which can approximate a sphere".

[0135] Silica fine particles (D1) can be used to create surface-modified silica, and can also be used to create hydrophobic surface-modified silica, because they are relatively easy to mix as a liquid curable composition and because a liquid curable composition with superior workability in the coating process can be easily obtained. Examples of hydrophobic surface-modified silica include silica on which trialkylsilyl groups having 1 to 20 carbon atoms, such as trimethylsilyl groups; dialkylsilyl groups having 1 to 20 carbon atoms, such as dimethylsilyl groups; alkylsilyl groups having 1 to 20 carbon atoms, such as octylsilyl groups; silica on which the surface has been treated with silicone oil; and so on. Hydrophobic surface-modified silica can be obtained, for example, by surface-modifying silica particles with a silane coupling agent having trialkylsilyl groups having 1 to 20 carbon atoms, dialkylsilyl groups having 1 to 20 carbon atoms, alkylsilyl groups having 1 to 20 carbon atoms, etc., or by treating silica particles with silicone oil.

[0136] Furthermore, the fine particles (D) may contain fine particles other than silica fine particles (D1). In other words, fine particles (D) may be silica fine particles (D1) alone, or a combination of one or more of the fine particles listed below. This makes it easier to obtain a cured product with superior heat resistance. For example, such fine particles include metals, metal oxides, minerals, metal carbonates, metal sulfates, metal hydroxides, metal silicates, organic components, silicones, etc. Also, the fine particles (D) used may have a modified surface.

[0137] Metals are elements belonging to groups 1 (excluding H), 2 through 11, 12 (excluding Hg), 13 (excluding B), 14 (excluding C and Si), 15 (excluding N, P, As and Sb), or 16 (excluding O, S, Se, Te and Po) of the periodic table.

[0138] Examples of metal oxides include titanium oxide, alumina, boehmite, chromium oxide, nickel oxide, copper oxide, zirconium oxide, indium oxide, zinc oxide, and composite oxides thereof. Fine particles of metal oxides also include sol particles composed of these metal oxides.

[0139] Minerals such as smectite and bentonite are examples. Examples of smectite include montmorillonite, beiderite, hectorite, saponite, stivunsite, nontronite, and souconite.

[0140] Examples of metal carbonates include calcium carbonate and magnesium carbonate; examples of metal sulfates include calcium sulfate and barium sulfate; examples of metal hydroxides include aluminum hydroxide; and examples of metal silicates include aluminum silicate, calcium silicate, and magnesium silicate. Examples of organic components include acrylic polymers.

[0141] Silicone refers to artificial polymer compounds that have a main skeleton composed of siloxane bonds. Examples include dimethylpolysiloxane, diphenylpolysiloxane, and methylphenylpolysiloxane.

[0142] The average primary particle diameter of microparticles other than silica microparticles (D1) can be 0.005 μm or more in one embodiment, 0.006 μm or more in another embodiment, 0.007 μm or more in yet another embodiment, and 7 μm or less in one embodiment, 2 μm or less in another embodiment, 0.1 μm or less in yet another embodiment, and 0.05 μm or less in yet another embodiment. The range of the average primary particle diameter of microparticles (D) can be 0.005 μm or more and 7 μm or less in one embodiment, 0.006 μm or more and 2 μm or less in another embodiment, 0.007 μm or more and 0.1 μm or less in yet another embodiment, and 0.007 μm or more and 0.05 μm or less in yet another embodiment. The average primary particle diameter of microparticles is obtained by observing the primary particles of 2000 randomly selected microparticles using a transmission electron microscope and averaging the particle diameter (nm) data obtained from 2000 particles. The average value is calculated as an integer, rounded to the first decimal place.

[0143] In one embodiment, the specific surface area of ​​the fine particles other than silica fine particles (D1) is 0.1 m². 2 / g or more, in another embodiment, 0.5m 2 / g or more, and in yet another embodiment, 1m 2 / g or more, and in yet another embodiment, 50m 2 It can be 1 / g or more, and in one embodiment, 500m 2 / g or less, in another embodiment, 400m 2 / g or less, and in yet another embodiment, 300m 2 / g or less, and in yet another embodiment, 220m 2 The amount can be less than or equal to / g. In one embodiment, the specific surface area range of the fine particles is 0.1 m². 2 / g or more 500m 2 / g or less, in another embodiment, 0.5m 2 / g or more 400m 2 / g or less, in yet another embodiment, 1m 2 / g or more 300m 2 / g or less, and in yet another embodiment, 50m 2 / g or more 220m 2 It can be less than / g.

[0144] The shape of the nanoparticles other than silica nanoparticles (D1) may be spherical, chain-like, needle-like, plate-like, flake-like, rod-like, fibrous, etc., and they can be spherical. Here, "spherical" means "approximately spherical, including polyhedral shapes that can approximate a sphere, such as ellipsoids, oval, konpeito-like, and cocoon-like shapes, in addition to perfect spheres."

[0145] The content of component (D) is not particularly limited, but can be 1 part by mass or more in one embodiment, 2 parts by mass or more in another embodiment, and 2.5 parts by mass or more in yet another embodiment, per 100 parts by mass of the liquid curable composition, and can be less than 25 parts by mass in one embodiment, less than 15 parts by mass in another embodiment, and less than 10 parts by mass in yet another embodiment. The range of the amount of component (D) can be 1 part by mass or more and less than 25 parts by mass in one embodiment, 2 parts by mass or more and less than 15 parts by mass in another embodiment, and 2.5 parts by mass or more and less than 10 parts by mass in yet another embodiment, per 100 parts by mass of the liquid curable composition. By using component (D) within the above range, the effect of adding component (D) can be more strongly expressed.

[0146] (Other components (E)) The liquid curable composition of this embodiment may contain other components (E). Component (E) may include antioxidants, ultraviolet absorbers, light stabilizers, etc. Antioxidants are added to prevent oxidative degradation during heating. Examples of antioxidants include phosphorus-based antioxidants, phenol-based antioxidants, sulfur-based antioxidants, etc.

[0147] Examples of phosphorus-based antioxidants include phosphates and oxaphosphaphenanthrene oxides. Examples of phenol-based antioxidants include monophenols, bisphenols, and high molecular weight phenols. Examples of sulfur-based antioxidants include dilauryl-3,3'-thiodipropionate, dimyristyl-3,3'-thiodipropionate, and distearyl-3,3'-thiodipropionate.

[0148] These antioxidants can be used individually or in combination of two or more. The amount of antioxidant used can be 3 parts by mass or less per 100 parts by mass of solid content of the liquid curable composition.

[0149] UV absorbers are added to improve the light resistance of the resulting liquid curable composition. Examples of UV absorbers include salicylic acids, benzophenones, benzotriazoles, and hindered amines. These UV absorbers can be used individually or in combination of two or more. The amount of UV absorber used can be 3 parts by mass or less per 100 parts by mass of solid content of the liquid curable composition.

[0150] Light stabilizers are added to improve the light resistance of the resulting liquid curable composition. Examples of light stabilizers include hindered amines such as poly[{6-(1,1,3,3,-tetramethylbutyl)amino-1,3,5-triazine-2,4-diyl}{(2,2,6,6-tetramethyl-4-piperidine)imino}hexamethylene{(2,2,6,6-tetramethyl-4-piperidine)imino}]. These light stabilizers can be used individually or in combination of two or more. The amount of light stabilizer used can be 5 parts by mass or less per 100 parts by mass of solid content of the liquid curable composition.

[0151] The total amount of other components (E), other than components (A), (B), (C), (D), and solvent (S), can be 10 parts by mass or less per 100 parts by mass of solid content of the liquid curable composition.

[0152] <Cured product according to this embodiment> The cured product according to this embodiment is a cured product of the liquid curable composition according to this embodiment (more specifically, a cured product of a layer of curable composition formed from the liquid curable composition according to this embodiment), and may contain the same components as those shown in the section "Liquid Curable Composition According to This Embodiment," except that components (A) and (B) are compounds formed by a condensation reaction. The cured product may, depending on the curing conditions, not contain solvent (S) or substantially not contain solvent (S).

[0153] (A compound formed by the condensation reaction of a curable organopolysiloxane compound (A) and a silane coupling agent (B)) The cured product according to this embodiment contains a compound obtained by the condensation reaction of a curable organopolysiloxane compound (A) and a silane coupling agent (B) using an acid component generated by a thermal acid generator (C) as a catalyst. In some cases, the condensation reaction may occur after hydrolysis of the curable organopolysiloxane compound (A) and the silane coupling agent (B). In one embodiment, the compound obtained by the condensation reaction of the curable organopolysiloxane compound and the silane coupling agent (B) is a compound obtained by the condensation reaction of a polysilsesquioxane compound and the silane coupling agent. The structure and functional groups of the curable organopolysiloxane compound (A) can be the same as those exemplified in the section "Liquid Curable Composition According to This Embodiment".

[0154] (Fine particles (D) and other components (E)) The cured product according to this embodiment contains fine particles (D) and other components (E). The structure, functional groups, content, and physical properties of the fine particles (D) and other components (E) can be the same as those exemplified in the section "Liquid Curable Composition According to This Embodiment".

[0155] (shape) The cured product according to this embodiment is a cured product of a layer of curable composition and therefore has a plate-like shape. That is, it is a plate-shaped cured product. In one embodiment, the plate-shaped cured product has multiple surfaces, for example, a pair of main surfaces (a first main surface and a second main surface) and a pair of side surfaces extending between the pair of main surfaces. The main surfaces are the first and second largest surfaces in area. The plate-shaped cured product can be a rectangular plate or a circular plate.

[0156] The thickness of the plate-shaped hardened material, which is the length between a pair of main surfaces, is not particularly limited and can be 500 μm or less in one embodiment, 400 μm or less in another embodiment, 300 μm or less in yet another embodiment, 50 μm or more in one embodiment, 75 μm or more in another embodiment, and 90 μm or more in yet another embodiment. The thickness range of the plate-shaped hardened material can be 50 μm or more and 500 μm or less in one embodiment, 75 μm or more and 400 μm or less in another embodiment, and 90 μm or more and 300 μm or less in yet another embodiment. Having a thickness within the above range makes it easier to use in optical components and the like.

[0157] The main surface area of ​​the plate-shaped cured material is approximately 710 cm², which is about the size of a typical 12-inch wafer, according to one embodiment. 2 In another embodiment, 400 cm 2 In yet another embodiment, 300 cm 2 It can be as follows, and in one embodiment, 10 cm 2 In another embodiment, 15 cm 2 In addition, another applicable 20cm 2 The above can be applied. In one embodiment, the area of ​​the main surface of the plate-shaped hardened material is 10 cm 2 More than 710cm 2 In another embodiment, 15cm 2 More than 400cm 2 In yet another embodiment, 20cm 2 More than 300cm 2The following is possible. Having the area within the above range makes it easier to use in optical components, etc.

[0158] (Total light transmittance) The cured product according to this embodiment exhibits a small difference in total light transmittance before and after heat treatment. Specifically, for a cured product with a thickness of 1 mm (cured product for transmittance measurement), when the total light transmittance at a wavelength of 450 nm is measured, the difference in total light transmittance before and after heat treatment is less than 5%. In another embodiment, the difference in total light transmittance can be less than 4%, in yet another embodiment less than 3%, in yet another embodiment less than 2%, and in yet another embodiment less than 1%. The above difference in total light transmittance indicates the degree of yellowing of the cured product, and by setting the value of the above difference in total light transmittance, a good optical component can be obtained.

[0159] The difference in total light transmittance before and after heat treatment of a cured material can be determined by measuring the total light transmittance T0 (%) at a wavelength of 450 nm of a cured material with a thickness of 1 mm before heat treatment (cured material for transmittance measurement), and then measuring the total light transmittance T1 (%) at a wavelength of 450 nm after heat treatment of the same cured material at 200°C for 168 hours, and calculating the difference between the two (T0-T1). Total light transmittance can be measured using a commercially available spectrophotometer (Shimadzu Corporation, product name "UV-VIS-NIR SPECTROPHOTOMETER UV-3600").

[0160] <Method for producing a liquid curable composition according to this embodiment> The liquid curable composition of this embodiment can be manufactured, for example, by a manufacturing method having the following steps (AI) and (AII).

[0161] (Process (AI)) Step (AI) is a step in which at least one of the compounds represented by the above formula (a-6) is polycondensed in the presence of a polycondensation catalyst to obtain a polysilsesquioxane compound.

[0162] (Process (AII)) Step (AII) is a step in which a liquid curable composition is obtained using the polysilsesquioxane compound obtained in step (AI).

[0163] A method for obtaining a polysilsesquioxane compound by polycondensing at least one of the compounds represented by the above formula (a-6) in step (AI) is the same as that exemplified in the section <Liquid curable composition according to this embodiment>.

[0164] In step (AII), a method for obtaining a liquid curable composition using a polysilsesquioxane compound includes, for example, mixing, degassing, and dissolving the polysilsesquioxane compound, component (B), component (C), and optionally components (B'), (D), and (E) with solvent (S). The mixing method and degassing method are not particularly limited, and known methods can be used. The order of mixing is not particularly limited. According to the manufacturing method having steps (AI) and (AII) described above, the liquid curable composition of this embodiment can be manufactured efficiently and simply.

[0165] <Method for forming a cured product and method for manufacturing individual pieces of cured product according to this embodiment> The cured product and cured individual pieces of this embodiment can be formed and manufactured, for example, by a method having the following steps (BI), (BII), and (BIII). (Process (BI)) Step (BI) is a step of applying the liquid curable composition of this embodiment obtained in step (AII) to a sheet-like substrate such as a release sheet.

[0166] (Process (BII)) Step (BII) is a step in which the coating film of the liquid curable composition obtained in step (BI) is heated, dried, and cured to obtain a cured product having a plate-like shape.

[0167] (Process (BIII)) Step (BIII) is a process in which the plate-shaped hardened material obtained in step (BII) is cut into a grid pattern to process it into individual plate-shaped pieces, thereby obtaining individual pieces of hardened material.

[0168] In process (BI), the liquid curable composition obtained in process (AII) is applied to a sheet-like substrate such as a release sheet. The application of the liquid curable composition to the release sheet may include (1) applying the liquid curable composition on the release sheet in a specific shape (circular plate shape (disc shape), square plate shape (rectangular parallelepiped shape)), (2) applying the liquid curable composition so that it covers the entire surface of the release sheet, or (3) preparing a release sheet equipped with a mold having recesses or holes of a specific shape (circular plate shape (disc shape), square plate shape (rectangular parallelepiped shape)), and applying (pouring) the liquid curable composition into the recesses or holes of the mold of the release sheet.

[0169] The method of applying the liquid curable composition onto a release sheet is not particularly limited, and examples include knife coating, blade coating, and roll coating. The liquid curable composition is stored in containers such as 18-liter cans, pails, and drums, and is used by supplying the liquid curable composition to a coating device.

[0170] The coating thickness of the liquid curable composition is not particularly limited and should be greater than or equal to the thickness of the target plate-shaped cured product. For example, the coating thickness of the liquid curable composition can be 700 μm or less in one embodiment, 570 μm or less in another embodiment, 430 μm or less in yet another embodiment, 50 μm or more in one embodiment, 75 μm or more in another embodiment, and 90 μm or more in yet another embodiment.

[0171] The release sheet to which the liquid curable composition is applied is not particularly limited, and for example, it may be a film on which the release agent is formed. The film is not particularly limited and is composed of an organic material or an inorganic material. As the organic material, a resin can be used, and as the inorganic material, ceramics, glass, metals, etc. can be used. In one embodiment, examples of films include polyester films such as polyethylene terephthalate film and polybutylene terephthalate film, polyolefin films such as polypropylene film and polymethylpentene film, plastic films such as polycarbonate film, metal foils such as aluminum and stainless steel, paper such as glassine paper, fine paper, coated paper, impregnated paper, and synthetic paper, and laminates thereof.

[0172] The thickness of the release sheet is not particularly limited and can be 20 μm or more in one embodiment, 25 μm or more in another embodiment, less than 200 μm in one embodiment, and less than 100 μm in another embodiment.

[0173] The release agent is not particularly limited and is composed of a resin. In one embodiment, examples of the release agent include polyolefins such as polyethylene resin, thermoplastic elastomers such as olefin-based thermoplastic elastomers, fluororesins such as tetrafluoroethylene, and silicone resins such as silicone having dimethylpolysiloxane as a basic skeleton.

[0174] The thickness of the release agent is not particularly limited; in one embodiment it can be 30 nm or more, in another embodiment it can be 50 nm or more, in one embodiment it can be less than 300 nm, and in another embodiment it can be less than 200 nm.

[0175] The mold used in (3) in the application of the liquid curable composition to the release sheet is not particularly limited and may, for example, have recesses or holes of a specific shape in the film. The film of the mold is also not particularly limited and may be formed from the same material as the film of the release sheet.

[0176] The thickness of the mold film is not particularly limited, and it is sufficient to form recesses or holes of the desired thickness for the plate-shaped cured product. For example, the thickness of the mold film can be 800 μm or less in one embodiment, 650 μm or less in another embodiment, 500 μm or less in yet another embodiment, 100 μm or more in one embodiment, 200 μm or more in another embodiment, and 250 μm or more in yet another embodiment.

[0177] Furthermore, the mold film may have a release agent formed on it, and the release agent and its thickness may be the same as the release agent of the release sheet film in terms of material and thickness.

[0178] In step (BII), the coating film of the liquid curable composition obtained in step (BI) is heated, dried, and cured to obtain a plate-shaped cured product. In the heating and drying of the applied liquid curable composition, the heating temperature can be 80°C or higher in one embodiment, 90°C or higher in another embodiment, 120°C or lower in one embodiment, and 110°C or lower in another embodiment. The heating temperature range can be 80 to 120°C in one embodiment, and 90 to 110°C in another embodiment. The heating time range can be 10 minutes to 1 hour in one embodiment, and 20 minutes to 30 minutes in another embodiment. As an example, it is demonstrated that the coating film of the liquid curable composition is heated and dried at 100°C for 20 minutes.

[0179] In the application of the liquid curable composition to the release sheet, in the layer of curable composition (dried product) formed by drying the liquid curable composition applied in the mold of (3), if a support member is required when the cured product is in the form of a plate, a support plate may be placed on the dried product. The support plate is not limited to any particular type and can be a plate made of a hard material having the same shape as the dried product, for example, a glass plate.

[0180] In the heat curing of a dried curable composition, the heating temperature can be 100°C or higher in one embodiment, 120°C or higher in another embodiment, 180°C or lower in one embodiment, and 160°C or lower in another embodiment. The range of heating temperature for curing can be 100 to 180°C in one embodiment, and 120 to 160°C in another embodiment. The range of heating time for curing can be 30 minutes to 10 hours in one embodiment, 1 hour to 7 hours in another embodiment, and 3 hours to 5 hours in yet another embodiment. As an example, it is illustrated that a dried curable composition is heated at 150°C for 4 hours to form a cured product.

[0181] After forming the plate-shaped cured product, the cured product of the liquid curable composition that covers the entire surface of the release sheet in step (2) of applying the liquid curable composition to the release sheet (in other words, the cured product of the layer of curable composition formed from the liquid curable composition) may be processed into a specific shape (circular plate shape (disc shape), square plate shape (rectangular parallelepiped shape)) in order to facilitate cutting in step (BIII) described later. The processing method is not particularly limited, and punching is an example.

[0182] After the plate-shaped cured product is formed, the cured product of the liquid curable composition formed in the mold of (3) in the application of the liquid curable composition to the release sheet, and the cured product of the liquid curable composition formed in the mold having a support plate are removed from the mold.

[0183] Step (BIII) is a process in which the plate-shaped cured material obtained in step (BII) is cut into a grid pattern to process it into individual plate-shaped pieces to obtain individual pieces of cured material. For cutting, the dicing method conventionally used when cutting semiconductor wafers such as silicon into a grid pattern can be used. The cured material formed on the release sheet is attached to the exposed adhesive surface of the dicing sheet used to fix it during dicing using a laminator or the like, and then the release sheet is peeled off. The dicing sheet is not particularly limited, and a normal dicing sheet can be used. The dicing sheet is attached to a frame, and the dicing apparatus is used to dic it into individual plate-shaped pieces having the desired shape. This gives individual pieces of cured material that have been cut into a grid pattern on the dicing sheet. The dicing apparatus is not particularly limited, and for example, a blade dicing apparatus using a particularly high-speed rotating blade can be used. The diced plate-shaped cured material is picked up individually from the dicing sheet.

[0184] The plate-shaped cured material obtained in this way can be used as an optical component or a molded body. As shown in <Liquid curable composition according to this embodiment>, the plate-shaped cured material can be used as an insulating member for a light-emitting device, etc.

[0185] <Summary of Embodiments> The disclosures herein include the following liquid curable compositions, cured products, and methods for forming cured products.

[0186] (1) A liquid curable composition, A curable organopolysiloxane compound, A silane coupling agent having two or more alkoxysilyl groups or silanol groups in its molecule, It contains a thermal acid generator, The liquid curable composition contains a compound having an acid anhydride in less than 1 part by mass per 100 parts by mass of solid content of the liquid curable composition. A liquid curable composition having a refractive index of 1.50 or higher.

[0187] (2) The liquid curable composition according to (1), wherein the curable organopolysiloxane compound is a polysilsesquioxane compound.

[0188] (3) The liquid curable composition described in (1) or (2), wherein, after curing, it is cut into a grid pattern and used as individual cured pieces.

[0189] (4) The liquid curable composition according to any one of (1) to (3), wherein the difference (T0-T1) between the total light transmittance T0 (%) at a wavelength of 450 nm in a 1 mm thick cured product prepared by curing the liquid curable composition and the total light transmittance T1 (%) at a wavelength of 450 nm in a 1 mm thick cured product after heat treatment of the 1 mm thick cured product at 200°C for 168 hours is less than 5%.

[0190] (5) A cured product prepared by curing any one of the liquid curable compositions described in (1) to (4), The hardened material has a plate-like shape, The main surface of the aforementioned hardened material is 710 cm². 2 A hardened material having the following area:

[0191] (6) Applying a liquid curable composition described in any one of (1) to (4) to a sheet, The liquid curable composition is heated to form a cured product having a plate-like shape, The cured material is cut into a grid pattern and processed into individual plate-like pieces. A method for producing individual hardened pieces containing [the specified substance]. [Examples]

[0192] The present invention will be described in more detail below with reference to examples. However, the present invention is not limited in any way to the following examples. Unless otherwise specified, parts and percentages in each example are by mass.

[0193] (average molecular weight measurement) The mass-average molecular weight (Mw) and number-average molecular weight (Mn) of the curable organopolysiloxane compound (A) obtained in the production example were measured using the following apparatus and conditions, converted to standard polystyrene equivalents. Device name: HLC-8220GPC, manufactured by Tosoh Corporation Column: A sequential concatenation of TSKgelGMHXL, TSKgelGMHXL, and TSKgel2000HXL. Solvent: tetrahydrofuran Injection volume: 20μl Measurement temperature: 40℃ Flow rate: 1ml / min Detector: Differential refractometer

[0194] (Measurement of IR spectrum) The IR spectrum of the curable organopolysiloxane compound (A) obtained in the manufacturing example was measured using a Fourier transform infrared spectrophotometer (PerkinElmer Spectrum100).

[0195] (Manufacturing Example 1) 28.91 g (145.8 mmol) of phenyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.) was charged into a 300 ml round-bottom flask. Then, an aqueous solution prepared by dissolving 0.0376 g of 35% hydrochloric acid (0.25 mol% relative to the total amount of silane compounds) in 7.874 ml of distilled water was added while stirring. The mixture was then stirred at 30°C for 2 hours, and then the temperature was raised to 70°C for 5 hours. After that, the reaction mixture was allowed to return to room temperature (23°C), and 50 g of propyl acetate and 100 g of water were added and liquid-liquid-liquid treatment was performed to obtain an organic layer containing the reaction product. Magnesium sulfate was added to this organic layer and it was dried. After removing the magnesium sulfate by filtration, the organic layer was concentrated using an evaporator, and the concentrate was vacuum-dried to obtain 17.0 g of a curable organopolysiloxane compound (A). The mass-average molecular weight (Mw) of the curable organopolysiloxane compound (A) was 1,100, and the molecular weight distribution (Mw / Mn) was 1.2. The IR spectral data for the curable organopolysiloxane compound (A) is shown below. Si-C6H5: 698cm -1 Si-O: 1132cm -1

[0196] The compounds used in the examples and comparative examples are shown below. (Component A) Curable organopolysiloxane compound (A): Organopolysiloxane compound obtained in Preparation Example 1 (solid at 23°C)

[0197] ((B) component) Silane coupling agent (B) having two or more alkoxysilyl or silanol groups in the molecule: Product name "KBM-9659" (1,3,5-N-tris[3-(trimethoxysilyl)propyl]isocyanurate), manufactured by Shin-Etsu Chemical Co., Ltd.

[0198] ((B') component) Compound (B') having an acid anhydride structure within the molecule: Product name "X-12-967C" (3-(trimethoxysilyl)propyl succinic anhydride), manufactured by Shin-Etsu Chemical Co., Ltd.

[0199] ((C) component) Thermoacid Generator (C1): Product name "SAN-AID SI-360" (1-naphthylmethylmethylp-hydroxyphenylsulfonium=hexafluorophosphate, acid generation temperature (i.e., peak temperature of the maximum endothermic peak obtained by differential scanning calorimetry): 125°C) Manufactured by Sanshin Chemical Industry Co., Ltd. Thermal acid generator (C2): Product name "TA-100FG" Manufactured by Sunapro Co., Ltd.

[0200] ((D) component) Silica microparticles (D): Product name "AEROSIL RX300" (Silica microparticles surface-treated with trimethylsilyl groups, average primary particle diameter: 7 nm, specific surface area: 210 m²) 2 / g) Manufactured by Nippon Aerosil Co., Ltd.

[0201] (Solvent (S)) Solvent (S): Toluene (SL) (Boiling point: 111°C)

[0202] (Preparation of liquid curable composition) Example 1 In terms of solid content (active ingredient) by mass ratio, 100 parts by mass of a curable organopolysiloxane compound (A) was added to 20 parts by mass of a silane coupling agent (B) having two or more alkoxysilyl or silanol groups in its molecule, and 0.1 parts by mass of a thermal acid generator (C1) (added as a 10% by mass toluene solution). A solvent (S) was then added to bring the solid content concentration to 85%, and the entire mixture was thoroughly mixed and degassed to obtain a liquid curable composition.

[0203] Examples 2 to 8, and Comparative Examples 1 and 2 Liquid curable compositions for Examples 2 to 8 and Comparative Examples 1 to 2 were obtained in the same manner as in Example 1, except that the types of compounds (components (B), (B'), (C), and (D)) and their blending ratios (mass ratio of solids (active ingredients)) were changed to those shown in Table 1 below. In addition, for Examples 2 to 4, 7, and 8, and Comparative Examples 1 and 2, the liquid curable compositions were prepared with solvent (S) to a solids content concentration of 85%, for Example 5, the liquid curable composition was prepared with solvent (S) to a solids content concentration of 75%, and for Example 6, the liquid curable composition was prepared with solvent (S) to a solids content concentration of 70%. In Table 1, the numbers in parentheses for component (B') (compound having an acid anhydride) represent the blending ratio of component (B') to 100 parts by mass of solids in the liquid curable composition.

[0204] [Table 1]

[0205] (Refractive index) The refractive index of the liquid curable composition obtained in Example 1 was measured at 25°C using a sodium D-line (wavelength 589 nm) as the light source, with an Abbe refractometer DR-M2 (manufactured by Atago Co., Ltd.). The refractive index of the liquid curable compositions obtained in Examples 2 to 8 and Comparative Examples 1 and 2 was measured in the same manner as in Example 1.

[0206] (Preparation of hardened material in a plate-like shape) The liquid curable composition obtained in Example 1 was heated and dried on the release surface of a release sheet (Lintec Corporation, product name "SP-PET382150", thickness: 38 μm) in which one side of a polyethylene terephthalate film had been released with a silicone-based release agent, covering an area of ​​25 cm² after heating and drying. 2Using an applicator, it was applied so as to be (5 cm in length × 5 cm in width). The applied layer was heat-treated at 100 °C for 20 minutes to obtain a layer of the curable composition. The layer of the curable composition was subjected to high-temperature curing at 150 °C for 3 hours to obtain a cured product in a plate shape with a thickness of 100 μm. In the same manner as in Example 1, plate-shaped cured products of Examples 2 to 8 and Comparative Examples 1 and 2 were obtained from the liquid curable compositions obtained in Examples 2 to 8 and Comparative Examples 1 and 2.

[0207] (Evaluation of Shape Stability of Plate-Shaped Cured Product) In the production of a plate-shaped cured product, an evaluation was made of attaching the cured product of Example 1 to a dicing sheet (manufactured by Lintec Corporation, product name "Adwill D-676H"). When attaching using a laminating roll under the conditions of an attaching pressure of 0.3 MPa, an attaching speed of 1 m / min, and an attaching temperature of 23 °C, the surface of the plate-shaped cured product was visually observed, and the shape was evaluated according to the following criteria. ○: The shape of the plate-shaped cured product before attaching the dicing sheet was maintained after attaching. ×: The shape of the plate-shaped cured product before attaching the dicing sheet was deformed after attaching (the plate-shaped cured product lacked toughness, and cracks occurred due to bending by the attaching pressure). In the same manner as in Example 1, the shapes of the cured products of Examples 2 to 8 and Comparative Examples 1 and 2 were evaluated.

[0208] (Total Light Transmittance) The liquid curable composition obtained in Example 1 was applied to the peeled surface of a peeling sheet (manufactured by Lintec Corporation, product name "SP-PET502150", thickness: 50 μm) whose one side of a polyethylene terephthalate film was peeled with a silicone-based peeling agent, and after heat drying, the area was 9 cm 2The mixture was applied to an area of ​​3 cm x 3 cm, treated at 100°C for 20 minutes, and then heated at 150°C for 3 hours to obtain a cured product (cured product for transmittance measurement) with a thickness of 1 mm. Cured products for transmittance measurement of Examples 2 to 8 and Comparative Example 1 were obtained from the liquid curable compositions obtained in Examples 2 to 8 and Comparative Example 1 in the same manner as in Example 1. The total light transmittance T0 (%) at a wavelength of 450 nm was measured for the cured product for transmittance measurement of Example 1 using a "UV-VIS-NIR SPECTROPHOTOMETER UV-3600" (manufactured by Shimadzu Corporation, using an integrating sphere). After heat treatment of the cured product for transmittance measurement at 200°C for 168 hours, the total light transmittance T1 (%) at a wavelength of 450 nm was measured. The transmittance difference T0-T1 (%) was calculated from the total light transmittance T0 (%) before heat treatment and the total light transmittance T1 (%) after heat treatment. In the same manner as in Example 1, the total light transmittance T0 (%) before heat treatment and the total light transmittance T1 (%) after heat treatment of the cured products for transmittance measurement in Examples 2 to 8 and Comparative Example 1 were measured, and the difference in total light transmittance T0-T1 (%) was determined from these values. In Comparative Example 2, a cured product for transmittance measurement that could be measured could not be formed, and therefore the total light transmittance could not be measured.

[0209] Table 2 shows the results for the evaluation of refractive index, shape stability, and total light transmittance for Examples 1 to 8 and Comparative Examples 1 and 2.

[0210] [Table 2]

[0211] The liquid curable compositions of Examples 1 to 8 exhibited excellent refractive index, and when their cured products were mounted on optical devices, they were able to improve the brightness of the optical devices. Furthermore, the cured products of Examples 1 to 8 showed excellent dimensional stability and differences in total light transmittance, and the liquid curable compositions of Examples 1 to 8 were able to form cured products in desired shapes while suppressing yellowing of the formed cured products.

[0212] On the other hand, the cured product of Comparative Example 1 showed a high difference in total light transmittance and yellowed after heat treatment. Comparative Example 2 failed to form a cured product, and therefore the difference in total light transmittance could not be evaluated.

[0213] Although embodiments of the invention have been described above, the invention is not limited to the above embodiments, and various modifications and changes are possible within the scope of the gist of the invention.

Claims

1. A liquid curable composition, A curable organopolysiloxane compound, A silane coupling agent having two or more alkoxysilyl groups or silanol groups in its molecule, It contains a thermal acid generator, The liquid curable composition contains a compound having an acid anhydride in an amount of less than 1 part by mass per 100 parts by mass of solid content of the liquid curable composition. A liquid curable composition having a refractive index of 1.50 or higher.

2. The liquid curable composition according to claim 1, wherein the curable organopolysiloxane compound is a polysilsesquioxane compound.

3. The liquid curable composition according to claim 1, wherein the liquid curable composition is cut into a grid pattern after curing and used as individual cured pieces.

4. The liquid curable composition according to claim 1, wherein the difference (T0-T1) between the total light transmittance T0 (%) at a wavelength of 450 nm in a 1 mm thick cured product prepared by curing the liquid curable composition and the total light transmittance T1 (%) at a wavelength of 450 nm in a 1 mm thick cured product after heat treatment of the 1 mm thick cured product at 200°C for 168 hours is less than 5%.

5. A cured product prepared by curing the liquid curable composition described in claim 1, The hardened material has a plate-like shape, The main surface of the aforementioned hardened material is 710 cm ２ A hardened material having the following area:

6. Applying the liquid curable composition described in claim 1 to a sheet, The liquid curable composition is heated to form a cured product having a plate-like shape, The cured material is cut into a grid pattern and processed into individual plate-like pieces. A method for producing hardened individual pieces containing [the specified ingredient].

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