Method for preparing solventless siloxane composition

Abstract

To provide a method for preparing a solventless siloxane composition which is solventless and has excellent temporal stability.SOLUTION: There is provided a method for preparing a solventless siloxane composition including the following steps (1), (2), and (3) in this order: (step 1): a step of reacting a silane-based compound to prepare a siloxane compound having a silanol group at a terminal thereof; (step 2): a step of adding an amide-based compound, and then performing dehydration and solvent distillation using an ortho ester; and (step 3): a step of dissolving the terminal silanol group-containing siloxane compound in an organic solvent, and then adding a capping agent to obtain a capped siloxane compound.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a method for producing a solventless siloxane composition. [Background technology]

[0002] Various lens materials, planarizing films, and other coating materials are used in solid-state imaging devices such as charge coupled devices (CCDs) and complementary metal-oxide semiconductor (CMOS) image sensors, as well as in display substrates and various anti-reflection films.

[0003] Such coating materials are required to have many properties such as heat resistance, low-temperature processability, etc., in addition to optical properties such as transparency and appropriate refractive index. In addition, depending on the application, alkali solubility is also required. It is known that a resin composition containing a siloxane compound is suitable for such requirements.

[0004] For example, Patent Document 1 discloses a composition for forming a low refractive index film, which contains a silicone resin obtained by hydrolysis and condensation of a mixed raw material containing two or more specific silane compounds. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2012-203059 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, the composition for forming a low refractive index film described in Patent Document 1 has a problem in that its stability over time is insufficient.

[0007] Moreover, the composition for forming a low refractive index film described in Patent Document 1 contains a solvent. In recent years, in view of environmental concerns, there has been a demand for solvent-free coatings. When the silicone resin described in Patent Document 1 is made highly concentrated and solvent-free, it gels due to a condensation reaction of the silanol groups, making it difficult to make it into a solvent-free type. [Means for solving the problem]

[0008] The present invention is a method for producing a solventless siloxane composition, comprising the following steps (1), (2), and (3) in this order: (Process 1) A process for producing a siloxane compound having a silanol group at its terminal by reacting a silane compound. (Process 2) A step of adding an amide compound, followed by dehydration with an orthoester and distilling off the solvent (Step 3) A step of dissolving the above-mentioned siloxane compound containing terminal silanol groups in an organic solvent, and then adding a sealing agent to obtain a sealed siloxane compound.

[0009] In the method for producing a solventless siloxane composition of the present invention, when a solventless siloxane composition having a low refractive index is to be obtained, it is preferable that the silane-based compound contains at least one compound selected from the group consisting of the following formula (1) and the following formulas (2) to (4): [ka] (In formula (1), A 1 represents a monovalent organic group having a radically polymerizable double bond; A 2 is an alkyl group or a siloxy group, R 1 represents an alkyl group. 1 may be the same or different. a is 0 or 1. [ka] (In formula (2), B 1 is an alkyl group, B 2 is a siloxy group, R2 represents an alkyl group. 2 may be the same or different. b is 0 or 1. [ka] (In formula (3), C 1 is an alkyl group, C 2 is a siloxy group, R 3 represents an alkyl group. 1 may be the same or different. 3 may be the same or different. c is 0 or 1. [ka] (In formula (4), D 1 is a fluoroalkyl group having 3 to 13 fluorine atoms, D 2 is an alkyl group, a siloxy group or a monovalent organic group having a radical polymerizable double bond; R 4 represents an alkyl group. 4 may be the same or different. d is 0 or 1. The silane compound preferably contains at least two compounds selected from the group consisting of the compounds represented by the formulas (2) to (4). The silane compound preferably contains the above formulas (2) and (3). In addition, the mass ratio in the above formula (1) is w 1 , the mass ratio in the above formula (2) is w 2 , the mass ratio in the above formula (3) is w 3 , the mass ratio in the above formula (4) is w 4 When we say, w 1 10~30,w 2 is 0 to 90, w 3 is 0 to 90, w 4 is 0 to 90, w 2 +w 3+ w 4 It is preferable that the molecular weight is 70 to 90. In addition, the mass ratio w 1 It is preferable that the value is 20 or less. The sealing agent is preferably hexamethyldisilazane. Effect of the Invention

[0010] The present invention can provide a method for producing a solventless siloxane composition that can provide a solventless siloxane composition that is excellent in stability over time. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] The method for producing a solventless siloxane composition of the present invention comprises the following steps (1), (2), and (3) in this order. (Process 1) A process for reacting a silane compound to produce a siloxane compound having a silanol group at its terminal. (Process 2) A step of adding an amide compound, followed by dehydration with an orthoester and distilling off the solvent (Step 3) A step of dissolving the above-mentioned siloxane compound containing terminal silanol groups in an organic solvent, and then adding a sealing agent to obtain a sealed siloxane compound.

[0012] [Process 1] Step 1 is a step of reacting a silane compound to produce a siloxane compound having a silanol group at its terminal.

[0013] In the above step 1, for example, a method can be mentioned in which a polymerization catalyst is added to a solution in which a silane compound is dissolved in an organic solvent, and the mixture is reacted under reflux.

[0014] Examples of the silane-based compound include silane-based compounds represented by the following formulas (1) to (4).

[0015] [ka] (In formula (1), A 1 represents a monovalent organic group having a radically polymerizable double bond; A 2 is an alkyl group or a siloxy group, R 1 represents an alkyl group. 1may be the same or different. a is 0 or 1. [ka] (In formula (2), B 1 is an alkyl group, B 2 is a siloxy group, R 2 represents an alkyl group. 2 may be the same or different. b is 0 or 1. [ka] (In formula (3), C 1 is an alkyl group, C 2 is a siloxy group, R 3 represents an alkyl group. 1 may be the same or different. 3 may be the same or different. c is 0 or 1. [ka] (In formula (4), D 1 is a fluoroalkyl group having 3 to 13 fluorine atoms; D 2 is an alkyl group, a siloxy group or a monovalent organic group having a radical polymerizable double bond; R 4 represents an alkyl group. 4 may be the same or different. d is 0 or 1.

[0016] In the above formula (1), A 1 is preferably a monovalent organic group having a vinyl group, an allyl group, or a (meth)acryloyl group.

[0017] In the above general formula (1), A 2 is preferably an alkyl group having 1 to 10 carbon atoms. Such an alkyl group is a methyl group, an ethyl group, a propyl group, an isopropyl group, a t-butyl group, a n-butyl group or a sec-butyl group.

[0018] In the above general formula (1), R 1is preferably an alkyl group having 1 to 10 carbon atoms. Such an alkyl group is a methyl group, an ethyl group, a propyl group, an isopropyl group, a t-butyl group, a n-butyl group or a sec-butyl group.

[0019] In the above general formula (1), a is preferably 0.

[0020] Examples of the above general formula (1) include vinyl silane compounds such as vinyl trimethoxy silane, vinyl triethoxy silane, methyl vinyl dimethoxy silane, and methyl vinyl diethoxy silane; 3-(meth)acryloyloxy propyl methyl dimethoxy silane, 3-(meth)acryloyloxy propyl trimethoxy silane, 3-(meth)acryloyloxy propyl ethyl diethoxy silane, and 3-(meth)acryloyloxy propyl triethoxy silane; and allyl silane compounds such as allyl trimethoxy silane and allyl triethoxy silane.

[0021] In the above formula (2), B 1 is preferably an alkyl group having 1 to 10 carbon atoms. Such an alkyl group is a methyl group, an ethyl group, a propyl group, an isopropyl group, a t-butyl group, a n-butyl group or a sec-butyl group.

[0022] In the above formula (2), B 2 is a siloxy group.

[0023] In the above formula (2), R 2 is preferably an alkyl group having 1 to 10 carbon atoms. Such an alkyl group is a methyl group, an ethyl group, a propyl group, an isopropyl group, a t-butyl group, a n-butyl group or a sec-butyl group.

[0024] In the above formula (2), b is preferably 0.

[0025] Examples of the above formula (2) include methyltrimethoxysilane, methyltriethoxysilane, methyltripoxysilane, methyltriisopropoxysilane, methyltri-n-butoxysilane, methyltri-t-butoxysilane, methyltri-sec-butoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, propyltrimethoxysilane, butyltrimethoxysilane, pentyltrimethoxysilane, hexyltrimethoxysilane, dimethyldimethoxysilane, and dimethyldiethoxysilane.

[0026] In the above formula (3), C 1 is preferably an alkyl group having 1 to 10 carbon atoms. Such an alkyl group is a methyl group, an ethyl group, a propyl group, an isopropyl group, a t-butyl group, a n-butyl group or a sec-butyl group.

[0027] In the above formula (3), C 2 is a siloxy group.

[0028] In the above formula (3), R 3 is preferably an alkyl group having 1 to 10 carbon atoms. Such an alkyl group is a methyl group, an ethyl group, a propyl group, an isopropyl group, a t-butyl group, a n-butyl group or a sec-butyl group.

[0029] In the above formula (3), c is preferably 0.

[0030] Examples of the above formula (3) include dimethyldimethoxysilane and dimethyldiethoxysilane.

[0031] In the above formula (4), D 1 can be appropriately selected depending on the application of the coating of the solventless siloxane composition. For example, in order to reduce the refractive index, it is preferable to select the number of fluorines in the range of 9 to 13. Furthermore, for example, in order to reduce the refractive index while maintaining the hardness, it is preferable to select the number of fluorines in the range of 3 to 5.

[0032] In the above formula (4), D 2 is preferably an alkyl group having 1 to 10 carbon atoms. Such an alkyl group is a methyl group, an ethyl group, a propyl group, an isopropyl group, a t-butyl group, a n-butyl group or a sec-butyl group.

[0033] In the above formula (4), R 4 is preferably an alkyl group having 1 to 10 carbon atoms. Such an alkyl group is a methyl group, an ethyl group, a propyl group, an isopropyl group, a t-butyl group, a n-butyl group or a sec-butyl group.

[0034] In the above formula (4), d is preferably 0.

[0035] Examples of the above formula (4) include trifluoropropylmethyldimethoxysilane, trifluoropropylmethyldiethoxysilane, trifluoropropylmethyldipropoxysilane, trifluoropropylmethyldiisopropoxysilane, trifluoropropylethyldimethoxysilane, trifluoropropylethyldiethoxysilane, heptadecafluorodecylmethyldimethoxysilane, tridecafluorooctylmethyldimethoxysilane, tridecafluorooctylmethyldiethoxysilane, tridecafluorooctylmethyldipropoxysilane, tridecafluorooctylmethyldiisopropoxysilane, trifluoropropylvinyldimethoxysilane, trifluoropropylvinyldiethoxysilane, and trifluoropropyltrialkoxysilane.

[0036] As the silane-based compound, compounds other than those represented by the formulas (1) to (4) may be used. Examples of such silane-based compounds include 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, tris-(trimethoxysilylpropyl)isocyanurate, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-isocyanatepropyltriethoxysilane, and 3-trimethoxysilylpropylsuccinic anhydride.

[0037] In the method for producing the solventless siloxane composition of the present invention, the above-mentioned silane-based compound may be appropriately selected and then the above-mentioned step 1 may be carried out.

[0038] In the method for producing a solventless siloxane composition of the present invention, when a solventless siloxane composition having a low refractive index is to be obtained, it is preferable that the silane compound contains at least one compound selected from the group consisting of the following formula (1) and the following formulas (2) to (4): The composition ratio for obtaining a solventless siloxane composition having a low refractive index will be described below.

[0039] The silane-based compound preferably contains at least two types selected from the group consisting of the above formulas (2) to (4), and more preferably contains the above formulas (2) and (3).

[0040] The mass ratio in the above formula (1) is w 1 , the mass ratio in the above formula (2) is w 2 , the mass ratio in the above formula (3) is w 3 , the mass ratio in the above formula (4) is w 4 When we say, w 1 10~30,w 2 is 0 to 90, w3 is 0 to 90, w 4 is 0 to 90, w 2 +w 3+ w 4 It is preferable that the molecular weight is 70 to 90. In addition, the above mass ratio w 1 ~w 4 means the mass ratio of the silane-based compound used in step 1 above.

[0041] The mass ratio w in the above formula (1) 1 is preferably 20 or less, and more preferably 15 or less.

[0042] The mass ratio w in the above formula (2) 2 is preferably 0 to 90, and more preferably 30 to 80.

[0043] The mass ratio w in the above formula (3) 3 is preferably 0-90, and more preferably 5-30.

[0044] The mass ratio w in the above formula (4) 4 is preferably 50 or less, more preferably 10 or less, and even more preferably 0 from the viewpoint of environmental load.

[0045] The amount of the silane-based compound other than those represented by the above formulas (1) to (4) is w 1 , w 2 , w 3 and w 4 It is preferably 1 to 10 parts by mass with respect to 100 parts by mass of the total mass of the above.

[0046] The organic solvent used in the above step 1 is preferably a lower alcohol such as ethanol, n-propyl alcohol, isopropyl alcohol, etc.; a ketone compound such as acetone, methyl ethyl ketone, etc.; or an ester compound such as ethyl acetate, n-propyl acetate, etc. Among these, lower alcohols are more preferred, and ethanol and isopropyl alcohol are even more preferred from the viewpoints of being able to maintain a moderate reaction temperature and being easy to distill off.

[0047] The polymerization catalyst used in the above step 1 may be, for example, an acid catalyst such as acetic acid, hydrochloric acid, or paratoluenesulfonic acid monohydrate, or a base catalyst such as ammonia, triethylamine, cyclohexylamine, or tetramethylammonium hydroxide.

[0048] The amount of the polymerization catalyst is preferably such that the number of molecules of the polymerization catalyst is about 0.05 to 0.2 times the number of all molecules of the silane-based compound.

[0049] The reaction temperature is preferably 60 to 80° C., and the reaction time is preferably about 2 to 24 hours so that the reaction proceeds sufficiently.

[0050] [Process 2] Step 2 is a step in which an amide compound is added, followed by dehydration with an orthoester and distillation off the solvent.

[0051] Examples of the amide compounds include N,N-dimethylacetamide, N,N-dimethylformamide, and N,N-diethylformamide.

[0052] The amount of the amide compound added is about 15 to 40% by mass based on the total amount of the silane compound.

[0053] After the amide compound is added, stirring is preferably performed. The stirring temperature at this time is preferably 10 to 40° C., and the stirring time is preferably 0.5 to 1 hour.

[0054] Examples of the orthoester include triethyl orthoacetate, trimethyl orthoformate, and triethyl orthoformate. By using the above orthoester, the water generated by the reaction can be removed.

[0055] When the orthoester is added dropwise, it is preferable to add it dropwise so that the temperature does not exceed 30° C. in order to prevent side reactions.

[0056] The method for distilling off the solvent is not particularly limited, and any known method, for example, distillation under reduced pressure, may be used.

[0057] The reaction between the siloxane compound having a silanol group at its terminal and the amide compound makes it possible to stabilize the siloxane compound containing a terminal silanol group.

[0058] [Process 3] Step 3 is a step of dissolving the above-mentioned terminal silanol group-containing siloxane compound in an organic solvent, adding at least one selected from an acid, an acid anhydride, an acid chloride, and an ester, and then adding a capping agent to obtain a capped siloxane compound.

[0059] As the organic solvent, the organic solvents described in step 1 above may be appropriately selected.

[0060] In the above step 3, it is preferable to add at least one selected from an acid, an acid anhydride, an acid chloride, and an ester, and then add a capping agent. The above acids, acid anhydrides, acid chlorides and esters include acetic anhydride, acetic acid, succinic acid, succinic anhydride and the like.

[0061] The amount of at least one selected from the group consisting of the acids, acid anhydrides, acid chlorides and esters is about 50 to 100% by mass based on the total mass of the sealant. This makes it possible to remove ammonia, which is a by-product produced when sealing with the sealant. The step of adding a sealing agent after adding at least one selected from the acid, acid anhydride, acid chloride and ester can be omitted since ammonia is not by-produced depending on the type of sealing agent.

[0062] Examples of the sealing agent include hexamethyldisilazane, chlorotrimethylsilane, trimethylsilyl acetate, N-(trimethylsilyl)diethylamine, N-trimethylsilylacetamide, and N-(trimethylsilyl)dimethylamine. Among these, hexamethyldisilazane is preferred from the viewpoint of cost.

[0063] The amount of the sealing agent added varies depending on the number of silanol groups in the siloxane compound containing a terminal silanol group, but is, for example, 50 mass % or more based on the total mass of the siloxane compound containing a terminal silanol group. When the amount of the sealant added is within the above range, the siloxane compound can be sufficiently sealed, and stability over time can be imparted. The upper limit of the amount of the sealing agent added is not particularly limited, but is, for example, 200% by mass based on the total mass of the siloxane compound containing a terminal silanol group.

[0064] In the above step 3, the reaction temperature is preferably 10 to 50° C. from the viewpoint of preventing side reactions.

[0065] In the above step 3, the reaction time is preferably about 3 to 15 hours so that the reaction proceeds sufficiently.

[0066] [others] After the above step 3, it is preferable to remove by-products and residues, and to distill off the organic solvent and water.

[0067] The by-products and residues can be removed by known methods, for example, by neutralizing them or mixing them with water.

[0068] The organic solvent and water can be removed by distillation using a known method. For example, water may be removed by using sodium sulfate, or the solvent may be removed by drying under reduced pressure.

[0069] By distilling off the organic solvent and water, a solventless siloxane compound can be obtained.

[0070] [Siloxane compounds] The blocked siloxane compound (also simply referred to as siloxane compound) obtained by the above steps 1 to 3 will now be described.

[0071] The siloxane compound preferably has a weight average molecular weight (Mw) of 800 to 10,000. If the weight average molecular weight (Mw) is less than 800, the film-forming property and curing property of the solventless siloxane composition described below may decrease, whereas if the weight average molecular weight (Mw) is more than 10,000, the viscosity may become too high. The siloxane compound more preferably has a weight average molecular weight (Mw) of 1,500 to 2,500.

[0072] The weight average molecular weight (Mw) can be measured by dissolving the siloxane compound to prepare a 0.02 part by mass solution, passing the solution through a filter (GL Sciences, GL Chromatodisk, aqueous 25A, pore size 0.2 μm), and then using Alliance (Nihon Waters) consisting of a size exclusion chromatograph and a refractive index detector under the following conditions: Column: pLgel mixed D (Agilent) x 2 connected in series Detector: alliance (manufactured by Japan Waters) Eluent: tetrahydrofuran (THF) Flow rate: 1.0ml / min Injection volume: 100μl

[0073] [Solvent-free siloxane composition] The solventless siloxane composition will now be described. The solventless siloxane composition contains the above-mentioned siloxane compound and additives described below. In this specification, "solvent-free type" means that the mass loss after 2 hours at 160°C under reduced pressure (5 hectopascals or less) is less than 1%.

[0074] The above-mentioned solventless siloxane composition may contain a leveling agent.

[0075] Examples of the leveling agent include silicone surfactants and fluorine surfactants. Among these, silicone-based surfactants are more suitable as the leveling agent in the present invention.

[0076] The content of the leveling agent is preferably 0.05 to 1 part by mass with respect to 100 parts by mass of the siloxane compound.

[0077] The solventless siloxane composition may contain a photopolymerizable compound.

[0078] The photopolymerizable compound is preferably a photopolymerizable compound having a radically polymerizable unsaturated double bond.

[0079] Examples of the photopolymerizable compound having two or more radically polymerizable unsaturated double bonds include ester compounds of divalent or higher hydroxyl group-containing compounds and (meth)acrylic acid, such as 1,3-butylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, tetrapropylene ... Examples of the acrylates include propylene glycol di(meth)acrylate, tetrapropylene glycol di(meth)acrylate, bisphenol A di(meth)acrylate, tris(2-hydroxyethyl)isocyanuric acid di(meth)acrylate, trimethylolpropane tri(meth)acrylate, glycerin tri(meth)acrylate, pentaerythritol tri(meth)acrylate, tris(2-hydroxyethyl)isocyanuric acid tri(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, and dipentaerythritol hexa(meth)acrylate.

[0080] Among these, from the viewpoint of being able to increase the crosslink density and impart excellent hardness to the cured coating, compounds having three or more reactive functional groups, for example, trimethylolpropane tri(meth)acrylate, glycerin tri(meth)acrylate, pentaerythritol tri(meth)acrylate, tris(2-hydroxyethyl)isocyanuric acid tri(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, and dipentaerythritol hexa(meth)acrylate are preferred, with tris(2-hydroxyethyl)isocyanuric acid tri(meth)acrylate and dipentaerythritol hexa(meth)acrylate being more preferred.

[0081] The photopolymerizable compound is preferably contained in an amount of 10 to 50 parts by mass relative to 100 parts by mass of the siloxane compound. If the content of the photopolymerizable compound is less than 10 parts by mass per 100 parts by mass of the siloxane compound, the curability of the cured coating film and the adhesion to the light-transmitting substrate or ITO electrode may be insufficient, whereas if the content of the photopolymerizable compound is more than 50 parts by mass per 100 parts by mass of the siloxane compound, the solubility of the uncured coating film in a developer may be insufficient.

[0082] The solventless siloxane composition may contain a polymerization initiator.

[0083] As the polymerization initiator, it is preferable to use a polymerization initiator that can provide a sufficient photocuring reaction when forming a cured coating.

[0084] Examples of the polymerization initiator include benzil, benzoin, benzophenone, camphorquinone, 2,2-dimethoxy-1,2-diphenylethane-1-one, 4,4'-bis(dimethylamino)benzophenone, 4,4'-bis(diethylamino)benzophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2,2-dimethoxy-2-phenylacetophenone, 2-methyl-[4'-(methylthio)phenyl]-2-morpholino-1-propanone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, and the like. Examples of such compounds include carbonyl compounds such as sphingoside oxides; trihalomethanes such as 1,3-bis(trichloromethyl)-5-(2'-chlorophenyl)-1,3,5-triazine and 2-[2-(2-furanyl)ethylenyl]-4,6-bis(trichloromethyl)-1,3,5-triazine; imidazole dimers such as 2,2'-bis(2-chlorophenyl)-4,5,4',5'-tetraphenyl-1,2'-biimidazole; thioxanthone compounds such as 2-isopropylthioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, and 2,4-dichlorothioxanthone; and biguanide compounds such as 1,2-diisopropyl-3-[bis(dimethylamino)methylene]guanidinium=2-(3-benzoylphenyl)propionate.

[0085] These polymerization initiators may be used alone or in combination of two or more thereof, and may also be combined with any photosensitizer. The siloxane compound may also be combined with a photoacid generator or a photobase generator, using the condensation reaction of the siloxane compound as an accelerating catalyst.

[0086] The polymerization initiator is preferably contained in an amount of 0.5 to 40 parts by mass when the total amount of the siloxane compound and the photopolymerizable compound is taken as 100 parts by mass.

[0087] If the content of the polymerization initiator is less than 0.5 parts by mass, the photopolymerizability decreases, and unreacted components may remain in the exposed area of ​​the photolithography method. If the content of the polymerization initiator is more than 40 parts by mass, the storage stability of the solventless siloxane composition may decrease. The amount of the polymerization initiator is more preferably 1 to 20 parts by mass when the total amount of the siloxane compound and the polymerizable monomer having two or more radically polymerizable unsaturated double bonds is 100 parts by mass.

[0088] (Other materials) To the above-mentioned solventless siloxane composition, it is possible to add, within the scope of not decreasing the effects of the present invention, chelate compounds of metals such as aluminum, zirconium, titanium, etc.; carbodiimide-based, isocyanate-based, crosslinking agents having crosslinkable functional groups such as epoxy groups or thiol groups; silicone-based, fluorine-based, etc. surfactants; photosensitizers such as aromatic hydrocarbon-based, amino compound-based, nitro compound-based, quinones, xanthones, etc.; polymerization inhibitors such as hydroquinone, methoquinone, hindered amines, hindered phenols, di-t-butylhydroquinone, 4-methoxyphenol, butylhydroxytoluene, nitrosamine salts, etc.; and fillers such as inorganic metal oxides and organic fine particles.

[0089] The solventless siloxane composition can be produced by charging an organic solvent into an appropriate container, and then, while stirring with, for example, a high-speed stirrer, charging and mixing the siloxane compound, if necessary, the photopolymerizable compound having two or more radically polymerizable unsaturated double bonds, the polymerization initiator, and other materials. It should be noted that the method for producing the solventless siloxane composition of the present invention is not limited to the above method, and the order in which the various materials are charged may be arbitrary. Furthermore, if a solid material is soluble in an organic solvent, it may be dissolved in advance before being charged, or if it is dispersible in an organic solvent directly or with the aid of a dispersant or the like, it may be dispersed in advance before being charged.

[0090] [How to form a cured film] The solventless siloxane composition is capable of forming a cured coating. The method for forming the cured coating preferably includes a coating step of coating a substrate with the solventless siloxane composition, an exposure step of irradiating the exposed area with active energy rays to form a cured coating, and a development step of dissolving and removing the coating liquid in the unexposed area with a developer. After the coating step, the composition may be thermally cured.

[0091] The coating method in the coating step, the active energy rays irradiated to the exposed area in the exposure step and the irradiation method thereof, and the developer for removing the coating liquid from the exposed area can be appropriately selected from those and methods used in conventional photolithography methods.

[0092] For example, the solventless siloxane composition is diluted so that the concentration of non-volatile components becomes 20% by mass, and then coated using a spin coater and heated (pre-baked) at 80°C for 3 minutes or the like. Then, using a mask aligner, the composition is heated at 100 mJ / cm 2 A test pattern is baked under the above irradiation conditions, immersed in a developer for 1 minute, and then heated (post-baked) at 150°C for 30 minutes, etc. to obtain a hardened coating. The pre-baking conditions are preferably 60 to 130° C. and 1 to 3 minutes. The above irradiation conditions are 50 to 260 mJ / cm 2 It is preferable that: The post-baking is preferably performed under conditions of 120 to 230° C. for 30 to 60 minutes.

[0093] The heat curing may be carried out, for example, by heating at 130° C. for 10 minutes and then at 180° C. for 60 minutes.

[0094] [Physical properties of solventless siloxane composition] The solventless siloxane composition of the present invention has excellent stability over time.

[0095] In this specification, the stability over time is evaluated by the following method.

[0096] The viscosity and weight average molecular weight of the solventless siloxane composition were compared immediately after preparation and after storage at 40°C for one week. If the increase in viscosity and weight average molecular weight is less than 15%, it is determined that the stability over time is excellent. The viscosity is measured (measurement temperature: 25° C.) using an R115 type viscometer RE-105L (E type viscometer, manufactured by Toki Sangyo Co., Ltd.), and the weight average molecular weight is measured by the method described above. If the increase in viscosity and weight average molecular weight is less than 15%, it can be determined that the stability over time is excellent.

[0097] The present specification discloses the following:

[0098] The present disclosure (1) is a method for producing a solventless siloxane composition, comprising the following steps (1), (2), and (3) in this order: (Process 1) A process for producing a siloxane compound having a silanol group at its terminal by reacting a silane compound. (Process 2) A step of adding an amide compound, followed by dehydration with an orthoester and distilling off the solvent (Step 3) A step of dissolving the above-mentioned siloxane compound containing terminal silanol groups in an organic solvent, and then adding a sealing agent to obtain a sealed siloxane compound. The present disclosure (2) is a method for producing the solventless siloxane composition according to the present disclosure (1), wherein the silane compound contains the above formula (1) and at least one selected from the group consisting of the above formulas (2) to (4). The present disclosure (3) is a method for producing the solventless siloxane composition according to the present disclosure (1) or (2), wherein the silane-based compound includes at least two compounds selected from the group consisting of the above formulas (2) to (4). The present disclosure (4) is a method for producing the solventless siloxane composition according to the present disclosure (3), in which the siloxane compound includes the above formulas (2) and (3). The present disclosure (5) is to change the mass ratio of the above formula (1) to w 1 , the mass ratio in the above formula (2) is w 2 , the mass ratio in the above formula (3) is w 3 , the mass ratio in the above formula (4) is w 4 When we say, w 1 10~30,w 2 is 0 to 90, w 3 is 0 to 90, w 4 is 0 to 90, w 2 +w 3+ w 4 The method for producing the solventless siloxane composition according to any one of the present disclosures (1) to (4), wherein the viscosity is 70 to 90. The present disclosure (6) relates to the mass ratio w 1 It is also a method for producing a solventless siloxane composition according to the present disclosure (5), in which The present disclosure (7) is also a method for producing a solventless siloxane composition according to any one of the present disclosures (1) to (6), in which the sealant is hexamethyldisilazane. EXAMPLES

[0099] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. Unless otherwise specified, "%" means "% by mass" and "parts" means "parts by mass."

[0100] The materials used in the examples and comparative examples are as follows.

[0101] (Silane-based compound of the above formula (1)) 3-Acryloxypropyltrimethoxysilane (Silane-based compound of the above formula (2)) Methyltriethoxysilane (Silane-based compound of the above formula (3)) Dimethyldimethoxysilane (Silane-based compound of the above formula (4)) Trifluoropropyltrimethoxysilane (Polymerization catalyst) Paratoluenesulfonic Acid Monohydrate (water) Ion-exchanged water (Amide compounds) N,N-Dimethylacetamide N,N-Dimethylformamide N,N-Diethylformamide (ortho ester) Trimethyl orthoacetate (Sealant) Hexamethyldisilazane Chlorotrimethylsilane

[0102] Example 1 59.3 g of methyltriethoxysilane, 10.0 g of dimethyldimethoxysilane, and 11.7 g of 3-acryloxypropyltrimethoxysilane were placed in a flask and stirred. On the other hand, a solution was prepared by mixing 0.05 g of paratoluenesulfonic acid monohydrate and 18.9 g of ion-exchanged water. The solution was added dropwise to the flask over 15 minutes so that the temperature did not exceed 60° C. After the addition, the mixture was stirred at 60° C. for 3 hours (step 1). After cooling, 15.1 g of N,N-dimethylacetamide was added and stirred. Next, 26.3 g of trimethyl orthoacetate was added dropwise so that the temperature did not exceed 30° C. Then, the by-products methanol, ethanol, and water were removed by vacuum distillation to obtain a concentrated solution of a siloxane compound containing terminal silanol groups (step 2). 33.0 g of ethyl acetate and 28.4 g of acetic anhydride were added to the concentrated solution of the siloxane compound containing terminal silanol groups and stirred. Next, 49.7 g of hexamethyldisilazane was added dropwise so that the temperature did not exceed 30°C, to obtain a solution of the siloxane compound capped with hexamethyldisilazane (step 3). 33.0 g of hexane and 33.0 g of ion-exchanged water were added to the solution of the siloxane compound sealed with hexamethyldisilazane, and after stirring in a separatory funnel, the mixture was left to stand until it separated into an organic layer and an aqueous layer, after which the aqueous layer was removed. After removing the aqueous layer, separation was performed using ion-exchanged water and a saturated aqueous solution of sodium bicarbonate, and the organic layer was taken out. 10.0g of sodium sulfate is added to the organic layer taken out, and the mixture is stirred for 10 minutes to dehydrate.Then, the solution is filtered using a filter.Then, the solution is distilled under reduced pressure at 60°C for 1 hour, and then distilled under reduced pressure at 120°C for 3 hours to distill off low-boiling components other than siloxane compounds, and a solventless siloxane composition containing siloxane compounds is obtained.

[0103] (Examples 2 to 6, 8) A solventless siloxane composition was obtained in the same manner as in Example 1, except that the amounts of the various materials added were changed as shown in Table 1.

[0104] Example 7 After carrying out steps 1 and 2 in the same manner as in Example 1, 33.0 g of ethyl acetate and 35.5 g of acetic anhydride were added to the concentrated solution of the siloxane compound containing terminal silanol groups and stirred. Next, 62.1 g of hexamethyldisilazane was added dropwise so that the temperature did not exceed 30°C, to obtain a solution of the siloxane compound sealed with hexamethyldisilazane (step 3). A solventless siloxane composition was obtained in the same manner as in Example 1, except for the above.

[0105] Example 9 A solventless siloxane composition was obtained in the same manner as in Example 1, except that the 15.1 g of N,N-dimethylacetamide used in step 2 in Example 1 was changed to 12.7 g of dimethylformamide.

[0106] Example 10 A solventless siloxane composition was obtained in the same manner as in Example 1, except that the 15.1 g of N,N-dimethylacetamide used in step 2 in Example 1 was changed to 17.5 g of diethylformamide.

[0107] Example 11 A solventless siloxane composition was obtained in the same manner as in Example 1, except that the acetic anhydride used in step 3 in Example 1 was changed to 33.5 g of acetic acid instead of 28.4 g.

[0108] Example 12 A solventless siloxane composition was obtained in the same manner as in Example 1, except that the 28.4 g of acetic anhydride used in step 3 in Example 1 was changed to 27.9 g of succinic anhydride.

[0109] Example 13 A solventless siloxane composition was obtained in the same manner as in Example 1, except that the 28.4 g of acetic anhydride used in step 3 in Example 1 was changed to 21.8 g of acetyl chloride.

[0110] Example 14 After carrying out steps 1 and 2 in the same manner as in Example 1, 33.0 g of ethyl acetate was added to the concentrated solution of the siloxane compound containing terminal silanol groups and stirred. Next, 66.8 g of chlorotrimethylsilane was added dropwise so that the temperature did not exceed 30°C, to obtain a solution of the siloxane compound sealed with chlorotrimethylsilane (step 3). A solventless siloxane composition was obtained in the same manner as in Example 1, except for the above.

[0111] Example 15 After carrying out steps 1 and 2 in the same manner as in Example 1, 33.0 g of ethyl acetate and 13.6 g of acetic anhydride were added to the concentrated solution of the siloxane compound containing terminal silanol groups and stirred. Next, 46.6 g of hexamethyldisilazane was added dropwise so that the temperature did not exceed 30°C, to obtain a solution of the siloxane compound sealed with hexamethyldisilazane (step 3). A solventless siloxane composition was obtained in the same manner as in Example 1, except for the above.

[0112] Comparative Example 1 59.3 g of methyltriethoxysilane, 10.0 g of dimethyldimethoxysilane, and 11.7 g of 3-acryloxypropyltrimethoxysilane were placed in a flask and stirred. On the other hand, a solution was prepared by mixing 0.045 g of paratoluenesulfonic acid monohydrate and 18.9 g of ion-exchanged water. The solution was added dropwise to the flask over 15 minutes so that the temperature did not exceed 60° C. After the addition, the mixture was stirred at 60° C. to react, but the reaction progressed over time and gelled.

[0113] <Stability over time> The viscosity and weight average molecular weight of the siloxane compositions of the Examples and Comparative Examples were measured immediately after preparation and after storage at 40° C. for one week, and were evaluated according to the following criteria. The viscosity was measured (measurement temperature: 25° C.) using an R115 type viscometer RE-105L (E type viscometer, manufactured by Toki Sangyo Co., Ltd.), and the weight average molecular weight was measured using the method described in this specification. (Evaluation Criteria) ○: The increase in viscosity and weight average molecular weight was less than 15%. △: Viscosity and weight average molecular weight increased by 15% or more ×: Gelled

[0114] [Table 1]

[0115] From the examples, it was confirmed that the method for producing a solventless siloxane composition of the present invention can provide a solventless siloxane composition that is solventless and has excellent stability over time. In Comparative Example 1, since gelation had progressed, it was not possible to measure the viscosity and weight average molecular weight after storage for one week. [Industrial Applicability]

[0116] It is possible to provide a method for producing a solventless siloxane composition that is solventless and has excellent stability over time.

Claims

1. A method for producing a solventless siloxane composition, comprising the following steps (1), (2), and (3) in this order: (Step 1) A process for reacting a silane compound to produce a siloxane compound having a silanol group at its terminal. (Step 2) A step of adding an amide compound, followed by dehydration with an orthoester and distilling off the solvent (Step 3) A step of dissolving the siloxane compound containing terminal silanol groups in an organic solvent, and then adding a sealing agent to obtain a sealed siloxane compound.

2. The method for producing a solventless siloxane composition according to claim 1, wherein the silane-based compound contains at least one compound selected from the group consisting of the following formula (1) and the following formulas (2) to (4): 【Chemistry 1】 (In formula (1), A １ represents a monovalent organic group having a radically polymerizable double bond; ２ is an alkyl group or a siloxy group, R １ represents an alkyl group. １ may be the same or different. a is 0 or 1. 【Chemistry 2】 (In formula (2), B １ is an alkyl group, B ２ is a siloxy group, R ２ represents an alkyl group. ２ may be the same or different; b is 0 or 1. 【Chemistry 3】 (In formula (3), C １ is an alkyl group, C ２ is a siloxy group, R ３ represents an alkyl group. １ may be the same or different. ３ may be the same or different; c is 0 or 1. 【Chemistry 4】 (In formula (4), D １ represents a fluoroalkyl group having 3 to 13 fluorine atoms; D ２ is an alkyl group, a siloxy group or a monovalent organic group having a radical polymerizable double bond; R ４ represents an alkyl group. ４ may be the same or different. d is 0 or 1.

3. 3. The method for producing a solventless siloxane composition according to claim 2, wherein the silane-based compound comprises at least two compounds selected from the group consisting of the compounds represented by formulas (2) to (4).

4. The method for producing a solventless siloxane composition according to claim 3, wherein the silane-based compound comprises the formulas (2) and (3).

5. The mass ratio in the formula (1) is w １ , the mass ratio in the formula (2) is w ２ , the mass ratio in the formula (3) is w ３ , the mass ratio in the formula (4) is w ４ When W １ 10 to 30, w ２ is 0 to 90, w ３ is 0 to 90, w ４ is 0 to 90, w ２ +w ３＋ W ４ The method for producing a solventless siloxane composition according to claim 1 or 2, wherein

6. The mass ratio w in the formula (1) １ The method for producing a solventless siloxane composition according to claim 5, wherein the molar ratio is 20 or less.

7. 3. The method for producing a solventless siloxane composition according to claim 1, wherein the sealant is hexamethyldisilazane.

Images