Coating-forming composition and production method for coating-forming composition

Abstract

Provided is a coating-forming composition that has excellent film-forming properties and stability over time. This coating-forming composition contains a siloxane compound and an organic solvent. The siloxane compound contains at least one substance selected from among constituent units derived from a silane compound having a Q unit, constituent units derived from a silane compound having a T unit, and constituent units derived from a silane compound having a D unit, has at least one end thereof capped by a dimethyl hydrosilyl group, and satisfies the following condition 1. (Condition 1) The siloxane compound satisfies expressions (1)-(6) where the mass ratio of a constituent unit derived from a silane compound having a Q unit relative to all constituent units is W1, the mass ratio of a constituent unit derived from a silane compound having a T unit relative to all constituent units is W2, and the mass ratio of a constituent unit derived from a silane compound having a D unit relative to all constituent units is W3.

Description

Film-forming composition and method for producing a film-forming composition

[0001] The present invention relates to a film-forming composition and a method for producing a film-forming composition.

[0002] The use of highly heat-resistant siloxane compounds as coating materials for semiconductors is being considered.

[0003] For example, Patent Document 1 discloses a composition for forming a low refractive index film, characterized by containing a silicone resin obtained by hydrolysis and condensation of a mixed raw material containing two or more specific silane compounds.

[0004] Japanese Patent Publication No. 2012-203059

[0005] However, the coating materials using siloxane compounds described in Patent Document 1 have not yielded materials that excel in both film-forming properties and long-term stability (the weight-average molecular weight and viscosity increase significantly over time), leaving room for further improvement.

[0006] Therefore, the present invention aims to provide a film-forming composition that is excellent in film-forming properties and stability over time.

[0007] The present invention relates to a film-forming composition comprising a siloxane compound and an organic solvent, wherein the siloxane compound contains at least one selected from a constituent unit derived from a silane compound having Q units, a constituent unit derived from a silane compound having T units, and a constituent unit derived from a silane compound having D units, and at least one end is sealed with a dimethylhydrosilyl group, satisfying the following condition 1: (Condition 1) The siloxane compound has a mass ratio of constituent units derived from a silane compound having Q units to the total constituent units of W １ The mass ratio of the constituent units derived from the silane compound having T units to the total constituent units is W. ２ The mass ratio of the constituent units derived from the silane compound having D units to the total constituent units is W. ３ In that case, the following equations (1) to (6) are satisfied.

[0008] In the film-forming composition of the present invention, the siloxane compound preferably has a weight-average molecular weight of 800 or more and 10,000 or less. The present invention also provides a method for producing the film-forming composition, comprising the following steps 1 and 2 in this order: (Step 1) A step of reacting at least one selected from a silane compound having Q units, a silane compound having T units, and a silane compound having D units in the presence of a catalyst to produce a siloxane compound having a silanol group at its terminus. (Step 2) A step of dissolving the siloxane compound having a silanol group at its terminus in an organic solvent, and then adding at least one selected from the group consisting of tetramethyldisiloxane, 1,1,3,3,5,5-hexamethyltrisiloxane, and 1,1,3,3-tetramethyldisilazane to produce a siloxane compound in which at least one terminus is sealed with a dimethylhydrosilyl group.

[0009] The present invention can provide a film-forming composition that exhibits excellent film-forming properties and long-term stability.

[0010] The film-forming composition of the present invention contains a siloxane compound and an organic solvent, wherein the siloxane compound contains at least one selected from a constituent unit derived from a silane compound having Q units, a constituent unit derived from a silane compound having T units, and a constituent unit derived from a silane compound having D units, and at least one end is sealed with a dimethylhydrosilyl group, satisfying the following condition 1. (Condition 1) The mass ratio of the constituent unit derived from the silane compound having Q units to the total constituent units of the siloxane compound is W １ The mass ratio of the constituent units derived from the silane compound having T units to the total constituent units is W. ２ The mass ratio of the constituent units derived from the silane compound having D units to the total constituent units is W. ３ In that case, the following equations (1) to (6) are satisfied.

[0011] <Siloxane Compounds> First, let's explain the siloxane compounds. In the film-forming composition of the present invention, the siloxane compound contains at least one selected from a constituent unit derived from a silane compound having a Q unit, a constituent unit derived from a silane compound having a T unit, and a constituent unit derived from a silane compound having a D unit.

[0012] (Silane compounds having Q units) Silane compounds having Q units have the structure shown in (1) below.

[0013]

[0014] Specific examples of silane compounds having a Q unit include tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetraisopropoxysilane, tetra-n-butoxysilane, and tetraisobutoxysilane. These may be used individually or in combination of two or more.

[0015] Among the silane compounds having Q units, tetraethoxysilane is preferred.

[0016] (Silane compounds having a T unit) Silane compounds having a T unit have the structure shown in (2) below.

[0017]

[0018] Specific examples of silane compounds having a T unit include methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxysilane, methyltriisopropoxysilane, methyltri-n-butoxysilane, methyltri-t-butoxysilane, methyltri-sec-butoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, propyltrimethoxysilane, butyltrimethoxysilane, pentyltrimethoxysilane, hexyltrimethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, vinyl Examples include trimethoxysilane, vinyltriethoxysilane, trifluoropropyltrialkoxysilane, trifluoropropyltrialkoxysilane, triethoxysilylpropyl succinic anhydride, triethoxysilylbutyl succinic anhydride, triethoxysilylethyl succinic anhydride, vinyltrimethoxysilane, vinyltriethoxysilane, 3-(meth)acryloyloxypropyltrimethoxysilane, 3-(meth)acryloyloxypropyltriethoxysilane, allyltrimethoxysilane, allyltriethoxysilane, etc. These may be used individually or in combination of two or more.

[0019] The silane compounds having a T unit are preferably methyltriethoxysilane and phenyltrimethoxysilane.

[0020] (Silane compounds having D units) Silane compounds having D units have the structure shown in (3) below.

[0021]

[0022] Specific examples of the silane compound having a D unit include trifluoropropylmethyldimethoxysilane, trifluoropropylmethyldiethoxysilane, trifluoropropylmethyldipropoxysilane, trifluoropropylmethyldiisopropoxysilane, trifluoropropylethyldimethoxysilane, trifluoropropylethyldiethoxysilane, heptadecafluorodecylmethyldimethoxysilane, tridecafluorooctylmethyldimethoxysilane, tridecafluorooctylmethyldiethoxysilane, tridecafluorooctylmethyldipropoxysilane, tridecafluorooctylmethyldiisopropoxysilane, trifluoropropylvinyldimethoxysilane, trifluoropropylvinyldiethoxysilane, dimethoxydimethylsilane, diethoxydimethylsilane, methylvinyldimethoxysilane, methylvinyldiethoxysilane, 3-(meth)acryloyloxypropylmethyldimethoxysilane, 3-(meth)acryloyloxypropylethyldiethoxysilane, and the like. These may be used alone or in combination of two or more.

[0023] As the silane compound having a D unit, dimethoxydimethylsilane is preferred.

[0024] (Condition 1) In the composition for film formation of the present invention, when the mass ratio of the structural unit derived from the silane compound having a Q unit to the total structural units is W １ , the mass ratio of the structural unit derived from the silane compound having a T unit to the total structural units is W ２ , and the mass ratio of the structural unit derived from the silane compound having a D unit to the total structural units is W ３ , the following formulas (1) to (6) are satisfied. Here, W １ , W ２ , W ３ , W ４ are numerical values representing each mass ratio as a percentage.

[0025] In the above formula (2), W １From the viewpoint of appropriately imparting film-forming properties, the value is preferably 5 or more, and more preferably 10 or more.

[0026] In the above formula (4), W ３ It is preferably 55 or less, and more preferably 50 or less.

[0027] In the above formula (5), W ４ From the viewpoint of appropriately imparting film-forming properties, the value is preferably 45 or higher, and more preferably 50 or higher.

[0028] (Sealing agent) In the film-forming composition of the present invention, the siloxane compound is sealed at least one terminal by a dimethylhydrosilyl group.

[0029] As a method for sealing at least one of the above-mentioned ends with a dimethylhydrosilyl group, for example, the end of the siloxane compound may be sealed with at least one selected from the group consisting of tetramethyldisiloxane, 1,1,3,3,5,5-hexamethyltrisiloxane, and 1,1,3,3-tetramethyldisilazane.

[0030] The amount of the above-mentioned encapsulant added is preferably 25 to 100% by mass relative to the total mass of the siloxane compound having a silanol group at the terminal end.

[0031] (Weight-average molecular weight) The siloxane compound preferably has a weight-average molecular weight of 800 or more and 10,000 or less. Having a weight-average molecular weight within the above range can suitably impart stability over time and film-forming properties. The above weight-average molecular weight is more preferably 1,000 or more, and more preferably 5,000 or less.

[0032] The weight-average molecular weight can be measured by dissolving the siloxane compound to prepare a 0.02 part by mass solution, passing it through a filter (GL Chromatodisk, aqueous system 25A, pore size 0.2 μm, manufactured by GL Sciences), and then using an alliance (manufactured by Waters Japan) consisting of size exclusion chromatography and a refractive index detector, under the following conditions: Column: pLgel mixed D (manufactured by Agilent) x 2 in series Detector: alliance (manufactured by Waters Japan) Eluent: THF Flow rate: 1.0 ml / min Injection volume: 100 μl

[0033] (Content of siloxane compound) In the film-forming composition of the present invention, the content of the siloxane compound is preferably 5% by mass or more, and more preferably 10% by mass or more, based on the total mass of the film-forming composition, from the viewpoint of appropriately providing stability over time. Furthermore, it is preferably 60% by mass or less, and more preferably 40% by mass or less.

[0034] <Organic Solvents> The film-forming composition of the present invention contains organic solvents.

[0035] As the above-mentioned organic solvents, organic solvents such as alcohols, polyhydric alcohols and their derivatives, ketone-based organic solvents, and ester-based organic solvents can be used.

[0036] Examples of the alcohols mentioned above include lower alcohols such as methanol, ethanol, n-propyl alcohol-n-, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, and sec-butyl alcohol.

[0037] Examples of the polyhydric alcohols mentioned above include ethylene glycol, propylene glycol, 1,2-butanediol, 1,3-butanediol, diethylene glycol, and dipropylene glycol.

[0038] Examples of derivatives of the above polyhydric alcohols include glycol monoethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono-n-propyl ether, ethylene glycol monoisopropyl ether, ethylene glycol mono-n-butyl ether, ethylene glycol monoisobutyl ether, ethylene glycol monophenyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono-n-propyl ether, propylene glycol monoisopropyl ether, propylene glycol mono-n-butyl ether, propylene glycol monoisobutyl ether, propylene glycol monophenyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol mono-n-propyl ether, diethylene glycol monoisopropyl ether, diethylene glycol mono-n-butyl ether, diethylene glycol monoisobutyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol-n-propyl ether, dipropylene glycol isopropyl ether, dipropylene glycol-n-butyl ether, and dipropylene glycol isobutyl ether.Also, for example, ethylene glycol monomethyl ether acetate, ethylene glycol monomethyl ether propionate, ethylene glycol monoethyl ether acetate, ethylene glycol mono-n-propyl ether acetate, ethylene glycol monoisopropyl ether acetate, ethylene glycol mono-n-butyl ether acetate, ethylene glycol monoisobutyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol mono-n-propyl ether acetate, propylene glycol monoisopropyl ether acetate, propylene glycol mono-n-butyl ether acetate, propylene glycol monoisobutyl ether acetate, die Examples of glycol monoether acylates include ethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol mono-n-propyl ether acetate, diethylene glycol monoisopropyl ether acetate, diethylene glycol mono-n-butyl ether acetate, diethylene glycol monoisobutyl ether acetate, dipropylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether acetate, dipropylene glycol mono-n-propyl ether acetate, dipropylene glycol monoisopropyl ether acetate, dipropylene glycol mono-n-butyl ether acetate, and dipropylene glycol monoisobutyl ether acetate.

[0039] Examples of the above-mentioned ketone-based organic solvents include acetone, methyl ethyl ketone, methyl-n-propyl ketone, methyl isopropyl ketone, methyl-n-butyl ketone, methyl isobutyl ketone, and cyclohexanone.

[0040] Examples of the ester-based organic solvents mentioned above include ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, n-amyl acetate, isoamyl acetate, methyl propionate, ethyl propionate, methyl lactate, ethyl lactate, and n-propyl lactate.

[0041] The above organic solvents can be used individually or in combination of two or more.

[0042] As for the above organic solvent, derivatives of secondary alcohols and ester-based organic solvents are preferred in terms of solubility of the above siloxane compound and coating suitability, and propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono-n-propyl ether, propylene glycol monoisopropyl ether, propylene glycol mono-n-butyl ether, propylene glycol monoisobutyl ether, propylene glycol monomethyl ether acetate, n-propyl acetate, and isopropyl acetate are more preferred.

[0043] In the film-forming composition of the present invention, the content of the above-mentioned organic solvent is not particularly limited, but for example, it may be 5% by mass or more and 95% by mass or less.

[0044] <Leveling agent> The film-forming composition of the present invention may contain a leveling agent.

[0045] Examples of the leveling agents mentioned above include silicone-based surfactants and fluorine-based surfactants. Among these, silicone-based surfactants are preferred from the viewpoint of film-forming properties and compatibility.

[0046] The content of the leveling agent is preferably 0.05 parts by mass or more and 1 part by mass or less per 100 parts by mass of the siloxane compound.

[0047] <Other> The film-forming composition of the present invention may also contain a photopolymerizable compound.

[0048] As the above-mentioned photopolymerizable compound, a photopolymerizable compound having two or more radically polymerizable unsaturated double bonds is preferred.

[0049] Examples of photopolymerizable compounds having two or more radical polymerizable unsaturated double bonds include ester compounds of a hydroxyl group-containing compound with divalent or higher hydroxyl groups 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, tricyclodecanedimethanol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, and tri Examples include propylene glycol di(meth)acrylate, tetrapropylene glycol di(meth)acrylate, bisphenol A di(meth)acrylate, tris(2-hydroxyethyl) isocyanurate di(meth)acrylate, trimethylolpropane tri(meth)acrylate, glycerin tri(meth)acrylate, pentaerythritol tri(meth)acrylate, tris(2-hydroxyethyl) isocyanurate tri(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, and dipentaerythritol hexa(meth)acrylate.

[0050] In particular, from the viewpoint of increasing the crosslinking density and imparting hardness to an excellent cured film, compounds having three or more reactive functional groups are preferred, such as trimethylolpropane tri(meth)acrylate, glycerin tri(meth)acrylate, pentaerythritol tri(meth)acrylate, tris(2-hydroxyethyl)isocyanurate tri(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, and dipentaerythritol hexa(meth)acrylate, with tris(2-hydroxyethyl)isocyanurate tri(meth)acrylate and dipentaerythritol hexa(meth)acrylate being more preferred.

[0051] The above photopolymerizable compound is preferably contained in an amount of 10 to 50 parts by mass per 100 parts by mass of the above siloxane compound.

[0052] The film-forming composition of the present invention may contain a polymerization initiator.

[0053] As the polymerization initiator mentioned above, it is preferable to use a polymerization initiator that can obtain a sufficient photocuring reaction when forming a cured film.

[0054] Examples of the polymerization initiators mentioned above include benzyl, 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-hydroxycyclohexylphenyl 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, and bis(2,4,6-trimethylbenzoyl)-phenylphosphine Examples include carbonyl compounds such as sphingoxides; trihalomethanes such as 1,3-bis(trichloromethyl)-5-(2'-chlorophenyl)-1,3,5-triazine and 2-[2-(2-furanyl)ethylenel]-4,6-bis(trichloromethyl)-1,3,5-triazine; imidazole dimers such as 2,2'-bis(2-chlorophenyl)4,5,4',5'-tetraphenyl1,2'-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]guanidium=2-(3-benzoylphenyl)propionate.

[0055] These polymerization initiators can be used individually or in combination of two or more. They can also be combined with any photosensitizer. Furthermore, they can be combined with photoacid generators or photobase generators as catalysts to accelerate the condensation reaction of the siloxane compounds mentioned above.

[0056] 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 100 parts by mass.

[0057] The film-forming composition of the present invention may contain, to the extent that it does not reduce the effects of the present invention, water, metal chelate compounds such as aluminum, zirconium, and titanium, carbodiimide-based, isocyanate-based, crosslinking agents having crosslinkable functional groups such as epoxy groups and thiol groups, photosensitizers such as aromatic hydrocarbons, amino compounds, nitro compounds, quinones, and xanthones, polymerization inhibitors such as hydroquinone, methoquinone, hindered amines, hindered phenols, di-t-butylhydroquinone, 4-methoxyphenol, butylhydroxytoluene, and nitrosamine salts, fillers such as inorganic metal oxides and organic fine particles, etc.

[0058] <Method for producing a film-forming composition> The method for producing the film-forming composition of the present invention comprises the following steps 1 and 2 in this order. (Step 1) A step of reacting at least one selected from a silane compound having a Q unit, a silane compound having a T unit, and a silane compound having a D unit in the presence of a polymerization catalyst to produce a siloxane compound having a silanol group at the end.

[0059] In step 1 described above, for example, a silane compound having a D unit, and one selected from a silane compound having a T unit and a silane compound having a Q unit are dissolved in water, and optionally in an organic solvent. An acid catalyst is then added to the solution and the mixture is reacted under reflux.

[0060] For at least one compound selected from silane compounds having Q units, silane compounds having T units, and silane compounds having D units, the one described above may be used.

[0061] The optimal amount of water used in the reaction is such that the number of water molecules is equal to the number of hydrolyzable substituents of the silane compound placed in the container. Since the silane compound used in the reaction has 2 to 4 hydrolyzable substituents per molecule, a simpler approach is to use an amount of water such that the number of water molecules is 3 to 4 times the total number of molecules of the silane compound placed in the container.

[0062] As organic solvents to be used as needed, lower alcohols such as ethanol, n-propyl alcohol, and isopropyl alcohol, ketone compounds such as acetone and methyl ethyl ketone, and ester compounds such as ethyl acetate and n-propyl acetate are preferred. Among these, lower alcohols are more preferred, and ethanol and isopropyl alcohol are even more preferred from the viewpoint of being able to maintain a suitable reaction temperature and being easily removed by distillation.

[0063] Examples of polymerization catalysts include acid catalysts and base catalysts, but acid catalysts are preferred. Examples of acid catalysts include acetic acid, hydrochloric acid, and p-toluenesulfonic acid hydrate, with strong acid catalysts being preferred. Examples of base catalysts include ammonia, triethylamine, cyclohexylamine, and tetramethylammonium hydroxide. The amount of polymerization catalyst used is preferably such that the number of polymerization catalyst molecules is 0.05 to 0.2 times the total number of molecules of the silane compound.

[0064] The reaction temperature for step 1 described above is preferably 60 to 120°C, and the reaction time is preferably approximately 2 to 24 hours to allow the reaction to proceed sufficiently.

[0065] After the reaction in step 1 is complete, by-products and other contaminants may be removed by known methods (extraction, dehydration, solvent removal, etc.) as needed.

[0066] (Step 2) A siloxane compound having a silanol group at one end is dissolved in an organic solvent, and then at least one selected from the group consisting of tetramethyldisiloxane, 1,1,3,3,5,5-hexamethyltrisiloxane, and 1,1,3,3-tetramethyldisilazane (sealing agent) is added to produce a siloxane compound in which at least one end is sealed with a dimethylhydrosilyl group.

[0067] The reaction temperature in step 2 is preferably 10 to 120°C from the viewpoint of suppressing side reactions. The reaction time can be any amount of time that allows the reaction to proceed sufficiently, for example, preferably 1 to 15 hours.

[0068] The amount of the above-mentioned encapsulant added is preferably 25 to 100% by mass relative to the total mass of the siloxane compound having a silanol group at the terminal end.

[0069] After step 2 described above, a film-forming composition can be obtained by mixing with an organic solvent, and optionally a leveling agent. The following matters are disclosed in this specification.

[0070] (1) The present disclosure is a film-forming composition containing a siloxane compound and an organic solvent, wherein the siloxane compound contains at least one selected from a constituent unit derived from a silane compound having Q units, a constituent unit derived from a silane compound having T units, and a constituent unit derived from a silane compound having D units, and at least one end is sealed with a dimethylhydrosilyl group, satisfying the following condition 1. (Condition 1) The mass ratio of the constituent unit derived from the silane compound having Q units to the total constituent units of the siloxane compound is W １ The mass ratio of the constituent units derived from the silane compound having T units to the total constituent units is W. ２ The mass ratio of the constituent units derived from the silane compound having D units to the total constituent units is W. ３ In that case, the following equations (1) to (6) are satisfied. Disclosure (2) is a film-forming composition according to Disclosure (1), wherein the siloxane compound has a weight-average molecular weight of 800 or more and 10,000 or less. Disclosure (3) is a method for producing the film-forming composition according to Disclosure (1) or (2), comprising the following steps 1 and 2 in this order: (Step 1) A step of reacting at least one selected from a silane compound having Q units, a silane compound having T units, and a silane compound having D units in the presence of an acid catalyst to produce a siloxane compound having a silanol group at the end. (Step 2) A step of dissolving the siloxane compound having a silanol group at the end in an organic solvent, and then adding at least one selected from the group consisting of tetramethyldisiloxane, 1,1,3,3,5,5-hexamethyltrisiloxane, and 1,1,3,3-tetramethyldisilazane to produce a siloxane compound in which at least one end is sealed with a dimethylhydrosilyl group.

[0071] 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 "mass percent" and "parts" means "parts by mass".

[0072] The materials used in the examples and comparative examples are as follows:

[0073] (Silane compounds with Q units) Tetraethoxysilane (TEOS) (Silane compounds with T units) Methyltriethoxysilane (MeTEOS) Vinyltrimethoxysilane (ViTMOS) Phenyltrimethoxysilane (PhTMOS) (Silane compounds with D units) Dimethoxydimethylsilane (Me ２ Si(OMe) ２ (Sealant) Tetramethyldisiloxane (TMDS) Hexamethyldisiloxane (HMDS) (Polymerization catalyst) p-Toluene sulfonic acid (PTSA) Nitric acid phosphate (Water) Ion-exchanged water (Organic solvent) Propylene glycol methyl ether acetate (PGMEA) Propylene glycol monomethyl ether (PGME)

[0074] (Synthesis of Siloxane Compounds in Examples 1-4) Silane compounds were mixed in the proportions shown in the table in a reaction vessel equipped with a stirrer, reflux condenser, thermometer, and dropping funnel. Each acid catalyst aqueous solution was added dropwise in the proportions shown in the table and stirred under reflux for 120 minutes (Step 1). Next, the sealing material (TMDS) shown in the table was added and stirred for another 120 minutes under reflux (Step 2). Then, PGMEA or PGME was added in the proportions shown in the table, and subsequently, methanol, ethanol, and water, which were reaction byproducts, were removed by distillation to obtain the film-forming compositions of Examples 1-4 with a solid content of 30 parts by mass. Note that the above mass ratio W １ , W ２ , W ３ , W ４ The calculations for these factors were calculated and are listed in the table. Furthermore, the amount of encapsulant added is indicated as the amount added relative to the total mass of the siloxane compound having a terminal silanol group (mass %).

[0075] (Synthesis of Siloxane Compounds in Comparative Examples 1-6) Silane compounds were mixed in the proportions shown in the table in a reaction vessel equipped with a stirrer, reflux condenser, thermometer, and dropping funnel. The aqueous solutions of each acid catalyst shown in the table were then added dropwise in the proportions shown in the table, and the mixture was stirred under reflux for 120 minutes. Next, in Comparative Example 2, the sealing agent (HMDS) shown in the table was added, and the mixture was stirred for another 120 minutes under reflux (this step was omitted in Comparative Examples 1, 3-6). Subsequently, PGMEA or PGME was added in the proportions shown in the table, and the reaction by-products methanol, ethanol, and water were removed by distillation to obtain the film-forming compositions of Comparative Examples 1-6 with a solid content of 30 parts by mass. Note that the above mass ratio W １ , W ２ , W ３ , W ４ The calculations for these factors were calculated and are listed in the table. Furthermore, the amount of encapsulant added is indicated as the amount added relative to the total mass of the siloxane compound having a terminal silanol group (mass %).

[0076]

[0077] <Film-forming properties> The film-forming compositions of the examples and comparative examples were prepared by adding a leveling agent: BYK-333 (manufactured by BYK Corporation) at a concentration of 1% by mass relative to the mass of the siloxane compound. Films were then formed under the following conditions: coating (spin coat 800 rpm, 60 s (film thickness 1 μm)) and curing (baking at 230°C for 30 minutes). Film-forming properties were evaluated according to the following criteria. The results are shown in Table 2. (Evaluation criteria) ○: Forms a film ×: Does not form a film

[0078] <Stability over Time> The viscosity and weight-average molecular weight of the film-forming compositions of the examples and comparative examples were measured immediately after preparation and after storage at 40°C or 60°C for one week, and evaluated according to the following criteria. The results are shown in Table 2. Viscosity was measured using an R115 type viscometer RE-105L (E type viscometer, manufactured by Toki Sangyo Co., Ltd.) (measurement temperature 25°C), and the weight-average molecular weight was measured using the method specified herein. (Evaluation Criteria) ○: Increase in viscosity and weight-average molecular weight was less than 25% △: Increase in viscosity or weight-average molecular weight was 25% or more and less than 100% ×: Increase in viscosity and weight-average molecular weight was 100% or more

[0079]

[0080] Table 2 confirms that the film-forming compositions described in the examples exhibit excellent film-forming properties and long-term stability.

[0081] This invention provides a film-forming composition that exhibits excellent film-forming properties and long-term stability.

Claims

1. A film-forming composition containing a siloxane compound and an organic solvent, wherein the siloxane compound contains at least one selected from a structural unit derived from a silane compound having a Q unit, a structural unit derived from a silane compound having a T unit, and a structural unit derived from a silane compound having a D unit, and at least one end is sealed with a dimethylhydrosilyl group, and satisfies the following condition 1. (Condition 1) The siloxane compound has a mass ratio of the structural unit derived from the silane compound having a Q unit to all the structural units as W １ , a mass ratio of the structural unit derived from the silane compound having a T unit to all the structural units as W ２ , and a mass ratio of the structural unit derived from the silane compound having a D unit to all the structural units as W ３ , and satisfies the following formulas (1) to (6) 2. The film-forming composition according to claim 1, wherein the siloxane compound has a weight-average molecular weight of 800 or more and 10,000 or less.

3. A method for producing a film-forming composition according to claim 1 or 2, comprising the following steps 1 and 2 in this order: (Step 1) A step of reacting at least one selected from a silane compound having Q units, a silane compound having T units, and a silane compound having D units in the presence of a catalyst to produce a siloxane compound having a silanol group at the end. (Step 2) A step of dissolving the siloxane compound having a silanol group at the end in an organic solvent, and then adding at least one selected from the group consisting of tetramethyldisiloxane, 1,1,3,3,5,5-hexamethyltrisiloxane, and 1,1,3,3-tetramethyldisilazane to produce a siloxane compound in which at least one end is sealed with a dimethylhydrosilyl group.

Images