JPWO2014112321A1 - Curable resin and method for producing the same - Google Patents

Abstract

Provided are a curable resin excellent in curability, heat resistance, and adhesion, and a method for producing the same, which are suitable for various binders, particularly for binder applications for high heat-resistant frame inks. A polyester (a) having a number average molecular weight of 500 to 10,000 and an acid value of 300 eq / t or less, a silicone resin (b), and a specific silane compound (c) are reacted to form an unreacted alkoxy A curable resin containing 0.1 to 30 groups per molecule.

Description

  The present invention relates to a novel curable resin obtained by reacting a polyester (a), a silicone resin (b), and a silane compound (c), and a method for producing the same.

  Conventionally, polyester resins have been used in various applications including coating applications and adhesive applications. Adhesives using polyester resins are generally excellent in adhesion to metals and various plastics, and thus are widely used for adhesives for electrical and electronic parts, adhesives for automobile parts, and the like. However, polyesters often suffer from degradation due to hydrolysis, which is a fatal defect of condensation polymers, and degradation due to exposure to high temperatures for a long time. Therefore, in order to exert heat resistance and curability while utilizing the adhesive properties of polyester, complicated blending such as a curing agent and a catalyst is required.

  Therefore, several systems have been proposed that are thermoplastic and have improved hydrolysis resistance. One of them is the use of aliphatic dicarboxylic acids such as adipic acid and sebacic acid as much as possible, and aromatic dicarboxylic acids. A polymer composed of diol and diol has been proposed and put to practical use. These have been put to practical use as adhesives for automobile parts, particularly as adhesives for fuel-feeding parts, but since the glass transition temperature is above room temperature, high temperatures are required to obtain sufficient adhesion to the substrate. Since adhesion at high pressure and heating of the base material are required, applicable base materials are limited (for example, see Patent Documents 1 and 2).

  In addition, those using polybutylene terephthalate or crystalline polyester such as polyethylene terephthalate as a hard segment and polyoxyalkylenes such as polytetramethylene glycol (PTMG) as a soft segment have been proposed and put into practical use. By having a flexible ether segment, a low glass transition temperature is realized and good adhesion to various substrates can be obtained. However, when a high degree of heat aging resistance and electrical insulation under severe humidification conditions are required, it is not always possible to obtain sufficiently satisfactory characteristics due to the low heat resistance of the ether segment and the high hygroscopicity compared to the ester segment. (For example, see Patent Documents 3 and 4).

JP 2002-88335 A JP 2003-073643 A Japanese Patent Laid-Open No. 8-48961 JP 2003-105302 A

  In particular, binders for frame inks used as adhesives for components of touch panels for smartphones and tablets in recent years are required to have high-temperature heat resistance (300 ° C x 30 minutes) and curability as well as adhesion. A curable resin satisfying all these qualities has not been proposed so far.

  As a result of intensive studies, the present inventors have found that the above problems can be solved by the following means, and have reached the present invention. That is, the present invention has the following configuration.

（式中、Ｒ^１は、それぞれ独立して、炭素原子数が１〜２０の直鎖構造、分岐構造、環状構造、および／またはヘテロ原子を有していてもよい基であり、Ｒ^２は、それぞれ独立して、炭素原子数１〜２０の直鎖構造、分岐構造、環状構造を有していてもよい炭化水素基、ｎは０〜３の整数である）A polyester (a) having a number average molecular weight of 500 to 10,000 and an acid value of 300 eq / t or less, a silicone resin (b), and a silane compound (c) represented by the following formula (1) are reacted. A curable resin containing 0.1 to 30 unreacted alkoxy groups per molecule.

(In the formula, each R ¹ is independently a group having 1 to 20 carbon atoms, which may have a straight chain structure, a branched structure, a cyclic structure, and / or a hetero atom, and R ² is , Each independently a hydrocarbon group optionally having a straight chain structure, a branched structure, or a cyclic structure having 1 to 20 carbon atoms, n is an integer of 0 to 3)

  The number average molecular weight of the silicone resin (b) is preferably 500 to 5,000, and preferably contains 1 to 20% by weight of silanol group and / or alkoxy group.

（式中、Ｒ^３は、それぞれ独立して、炭素原子数が１〜２０の直鎖構造、分岐構造、環状構造を有していてもよい炭化水素基であり、Ｒ^４は、それぞれ独立して、水素原子、または炭素原子数が１〜２０の直鎖構造、分岐構造、環状構造を有していてもよい炭化水素基である）It is preferable that the silicone resin (b) includes any one or more of structural units represented by the following formulas (2) to (4).

(In the formula, each R ³ is independently a hydrocarbon group having 1 to 20 carbon atoms, which may have a linear structure, a branched structure, or a cyclic structure, and each R ⁴ is independently And a hydrocarbon group which may have a hydrogen atom or a straight chain structure having 1 to 20 carbon atoms, a branched structure, or a cyclic structure)

  An ink comprising the curable resin according to any one of the above.

  An adhesive comprising the curable resin according to any one of the above.

（式中、Ｒ^１は、それぞれ独立して、炭素原子数が１〜２０の直鎖構造、分岐構造、環状構造、および／またはヘテロ原子を有していてもよい基であり、Ｒ^２は、それぞれ独立して、炭素原子数１〜２０の直鎖構造、分岐構造、環状構造を有していてもよい炭化水素基、ｎは０〜３の整数である）The method for producing a curable resin according to any one of the above, wherein 0.1 to 20 unreacted silanol groups or alkoxy groups remain per molecule of the polyester (a) and the silicone resin (b). A method for producing a curable resin, in which after the polymerization, the silane compound (c) is further polymerized until 0.1 to 30 unreacted alkoxy groups remain per molecule.

(In the formula, each R ¹ is independently a group having 1 to 20 carbon atoms, which may have a straight chain structure, a branched structure, a cyclic structure, and / or a hetero atom, and R ² is , Each independently a hydrocarbon group optionally having a straight chain structure, a branched structure, or a cyclic structure having 1 to 20 carbon atoms, n is an integer of 0 to 3)

  The curable resin concerning this invention is excellent in sclerosis | hardenability, heat resistance, and adhesiveness, and is suitable for various binder uses. In particular, it is suitable for binder applications for high heat-resistant frame ink.

<Polyester (a)>
Although it does not specifically limit as an acid component which comprises polyester (a) used for this invention, Dicarboxylic acid can be used. Specifically, terephthalic acid, isophthalic acid, orthophthalic acid, phenylenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid and other aromatic dicarboxylic acids, succinic acid, glutaric acid, adipic acid, azelaic acid, sebacic acid, dodecanedioic acid Aliphatic dicarboxylic acids such as dimer acid, 1,4-cyclohexanedicarboxylic acid, tetrahydrophthalic acid, hexahydroisophthalic acid, 1,2-cyclohexene dicarboxylic acid, etc., fumaric acid, maleic acid, terpene Examples thereof include unsaturated dicarboxylic acids such as maleic acid adducts, and one or more of these can be selected and used. Among these, terephthalic acid, isophthalic acid, and orthophthalic acid are preferably used as the aromatic dicarboxylic acid, and adipic acid is preferably used as the aliphatic dicarboxylic acid. As an acid component contained in the polyester (a), the combined content of aromatic dicarboxylic acid and alicyclic dicarboxylic acid is preferably 10 to 100 mol%, more preferably 15 to 95 mol%, and more preferably 20 to 90 mol%. Further preferred. The content of the aliphatic dicarboxylic acid is preferably 0 to 90 mol%, more preferably 5 to 85 mol%, and further preferably 10 to 80 mol%. If the combined content of aromatic dicarboxylic acid and alicyclic dicarboxylic acid is less than 10 mol%, the heat resistance may be insufficient, which is not preferable. If the content of the aliphatic dicarboxylic acid exceeds 90 mol%, the heat resistance may be insufficient, which is not preferable.

  Although it does not specifically limit as a polyol component which comprises polyester (a) used for this invention, A diol component is preferable, for example, ethylene glycol, 1,2-propylene glycol, 1,3-propanediol, 2-methyl-1, 3-propanediol, neopentyl glycol, 3-methyl-1,5-pentanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,4-pentanediol, 1, 3-pentanediol, 2,4-diethyl-1,5-pentanediol, 1,6-hexanediol, 1-methyl-1,8-octanediol, 3-methyl-1,6-hexanediol, 4-methyl -1,7-heptanediol, 4-methyl-1,8-octanediol, 4-propyl-1,8-octa Diols, aliphatic glycols such as 1,9-nonanediol, polyether glycols such as diethylene glycol, triethylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, 1,2-cyclohexanedimethanol, 1,3-cyclohexane Examples include alicyclic diols such as dimethanol, 1,4-cyclohexanedimethanol, tricyclodecane glycols, and water-added bisphenols, and one or more of these can be selected and used. Among these, it is preferable to use ethylene glycol, 2-methyl-1,3-propanediol, or neopentyl glycol.

  In the polyester (a) used in the present invention, a tricarboxylic or higher functional component may be copolymerized with the dicarboxylic acid component and / or the diol component. The tri- or higher functional polycarboxylic acid component is not particularly limited, and examples thereof include trimellitic acid, pyromellitic acid, benzophenone tetracarboxylic acid, and anhydrides thereof. Examples of the tri- or higher functional polyol include glycerin, trimethylolethane, Examples include trimethylolpropane, mannitol, sorbitol, pentaerythritol, α-methylglucoside. The use of these increases the number of reaction points, which is preferable for producing a reactant with the silicone resin (b). As a polyol component contained in the polyester (a), a diol component and a tri- or higher functional polyol component can be blended in an arbitrary ratio. Although not particularly limited, a preferable blending ratio is diol component / trifunctional or higher polyol component = 100/0 to 0/100 (molar ratio), more preferably 97/3 to 3/97 (molar ratio), 94 / 6 to 6/94 (molar ratio) is more preferable, and 90/10 to 10/90 (molar ratio) is particularly preferable. Further, it may be 50/50 (molar ratio).

  The number average molecular weight of the polyester (a) used in the present invention needs to be 500 to 10,000. 800 to 7,500 is more preferable, and 1,000 to 5,000 is even more preferable. If it is less than 500, a tough crosslinked film may not be obtained, and if it exceeds 10,000, the compatibility with the silicone resin (b) may be reduced, making it difficult to obtain a polymer. .

  The reduced viscosity of the polyester (a) used in the present invention is preferably 0.05 to 0.5 dl / g, more preferably 0.08 to 0.45 dl / g, still more preferably 0.09 to 0.4 dl / g, 0.1 to 0.35 dl / g is particularly preferred. If it is less than 0.05 dl / g, a tough crosslinked coating film may not be obtained. If it exceeds 0.50 dl / g, the compatibility with the silicone resin (b) decreases and it becomes difficult to obtain a polymer. This is not preferable.

  The acid value may be imparted to the polyester (a) used in the present invention by any method. By giving an acid value, effects such as improved curability and improved adhesion to the substrate may be obtained. As a method for giving an acid value, a depolymerization method in which a polyvalent carboxylic acid anhydride is added in the latter stage of polycondensation, this is made to have a high acid value at the prepolymer (oligomer) stage, and then this is polycondensed to give an acid value. There is a method of obtaining the polyester (a) having, for example, but the former depolymerization method is preferred because it is easy to operate and a target acid value is easily obtained.

  The polyvalent carboxylic acid anhydride used for acid addition in such a depolymerization method is not particularly limited. For example, phthalic anhydride, tetrahydrophthalic anhydride, succinic anhydride, trimellitic anhydride, pyromellitic anhydride, And hexahydrophthalic anhydride. Trimellitic anhydride is preferable.

  The acid value of the polyester (a) used in the present invention needs to be 300 eq / t or less. 280 eq / t or less is more preferable, and 250 eq / t or less is more preferable. If it exceeds 300 eq / t, impurities such as decomposition products are likely to increase when heat-treated under heat resistance evaluation conditions (300 ° C. × 30 minutes), which may cause coloring, which is not preferable. The acid value may be 0 eq / t, preferably 1 eq / t or more, and more preferably 5 eq / t or more.

  As a method for producing the polyester (a) used in the present invention, a known method can be used. For example, a dicarboxylic acid component, a diol component and, if necessary, a trifunctional or higher polycarboxylic acid component or an anhydride thereof, After the polyol component is esterified at 150 to 250 ° C., the polyester (a) can be obtained by polycondensation reaction at 230 to 300 ° C. while reducing the pressure. Alternatively, a polyester (a) is obtained by performing a transesterification reaction at 150 ° C. to 250 ° C. using a derivative such as dimethyl ester of polycarboxylic acid and a polyol component and then performing a polycondensation reaction at 230 ° C. to 300 ° C. while reducing the pressure. Can be obtained.

  The polyester (a) used in the present invention may be either amorphous or crystalline, but amorphous polyester is more preferred from the viewpoint of solubility in a solvent.

<Silicone resin (b)>
The silicone resin (b) used in the present invention is not particularly limited, but is preferably a resin having a silanol group and / or an alkoxy group as a reactive group. More preferably, it is a resin containing any one or more of the structural units represented by the formulas (2) to (4). The silicone resin (b) may be grafted with an aromatic hydrocarbon, an aliphatic hydrocarbon, an alicyclic hydrocarbon, or the like. Although it does not specifically limit as a silicone resin (b), For example, a phenyl alkyl type silicone resin can be used.

  The content of silanol groups and / or alkoxy groups in the silicone resin (b) used in the present invention is preferably 1 to 20% by weight, more preferably 2 to 17% by weight. If the amount is less than 1% by weight, the reaction with the polyester (a) may be insufficient and it may be difficult to obtain a polymer. If the amount exceeds 20% by weight, the branched structure may increase and the polymer may gel. This is not preferable.

  The number average molecular weight of the silicone resin (b) used in the present invention is preferably 500 to 5,000, more preferably 700 to 4,500, and still more preferably 1,000 to 4,000. If it is less than 500, the heat resistance may be insufficient, and if it exceeds 5,000, the compatibility with the polyester is lowered and it may be difficult to obtain a polymer.

ここで、Ｒ^３は、それぞれ独立して、直鎖構造、分岐構造、環状構造を有していてもよい炭化水素基であり、炭素原子数は１〜２０が好ましく、２〜１０がより好ましく、３〜６がさらに好ましい。具体的には、例えば、メチル基、エチル基、ノルマルプロピル基、イソプロピル基等の脂肪族炭化水素、フェニル基、ナフチル基等の芳香族炭化水素、シクロヘキシル基、シクロペンチル基等の脂環族炭化水素等が挙げられるがこれらに限定されない。Ｒ^４は、それぞれ独立して、水素原子、または直鎖構造、分岐構造、環状構造を有していてもよい炭化水素基であり、炭化水素基である場合の炭素原子数は１〜２０が好ましく、１〜１０がより好ましく、１〜５がさらに好ましく、１〜２が最も好ましい。具体的には、例えば、メチル基、エチル基、ノルマルプロピル基、イソプロピル基等の脂肪族炭化水素、フェニル基、ナフチル基等の芳香族炭化水素、シクロヘキシル基、シクロペンチル基等の脂環族炭化水素等が挙げられるがこれらに限定されない。これらシリコーン樹脂（ｂ）は単独で、又は２以上を併用して使用することができる。Although the silicone resin (b) used for this invention is not specifically limited, It is preferable that it is resin containing any one or more of the structural units shown by following formula (2)-(4).

Here, R ³ is each independently a hydrocarbon group which may have a linear structure, a branched structure, or a cyclic structure, and the number of carbon atoms is preferably 1-20, more preferably 2-10. 3 to 6 are more preferable. Specifically, for example, aliphatic hydrocarbon such as methyl group, ethyl group, normal propyl group and isopropyl group, aromatic hydrocarbon such as phenyl group and naphthyl group, alicyclic hydrocarbon such as cyclohexyl group and cyclopentyl group However, it is not limited to these. R ⁴ is each independently a hydrogen atom or a hydrocarbon group that may have a straight chain structure, a branched structure, or a cyclic structure, and the number of carbon atoms in the case of the hydrocarbon group is 1 to 20 1-10 are more preferable, 1-5 are more preferable, and 1-2 are the most preferable. Specifically, for example, aliphatic hydrocarbon such as methyl group, ethyl group, normal propyl group and isopropyl group, aromatic hydrocarbon such as phenyl group and naphthyl group, alicyclic hydrocarbon such as cyclohexyl group and cyclopentyl group However, it is not limited to these. These silicone resins (b) can be used alone or in combination of two or more.

<Silane compound (c)>
The silane compound (c) used in the present invention needs to have a structure represented by the following formula (1). When the silane compound (c) is not of the structure represented by the following formula (1), any one of curability, adhesion, and heat resistance is used. The above tends to be inferior.
R ¹ _n Si (OR ² ) _4-n (1)
Here, each R ¹ is independently a linear structure, a branched structure, a cyclic structure, and / or a group that may have a hetero atom, and preferably has 1 to 20 carbon atoms, 10 is more preferable, and 3 to 6 is more preferable. Specifically, for example, aliphatic hydrocarbon such as methyl group, ethyl group, normal propyl group and isopropyl group, aromatic hydrocarbon such as phenyl group and naphthyl group, alicyclic hydrocarbon such as cyclohexyl group and cyclopentyl group However, it is not limited to these. R ² is each independently a hydrocarbon group that may have a linear structure, a branched structure, or a cyclic structure, the number of carbon atoms is preferably 1-20, more preferably 1-10, 5 is more preferable, and 1-2 is most preferable. Specifically, for example, aliphatic hydrocarbon such as methyl group, ethyl group, normal propyl group and isopropyl group, aromatic hydrocarbon such as phenyl group and naphthyl group, alicyclic hydrocarbon such as cyclohexyl group and cyclopentyl group However, it is not limited to these. n is an integer of 0-3.

  Although the molecular weight of a silane compound (c) is not specifically limited, It is preferable that it is less than 500, The more preferable molecular weight is 450 or less, More preferably, the molecular weight is 400 or less. The molecular weight is preferably 100 or more.

  The silane compound (c) is not particularly limited. For example, methyltrimethoxysilane, dimethyldimethoxysilane, trimethylmethoxysilane, phenyltrimethoxysilane, tetraethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, phenyltriethoxysilane , Ethyltrimethoxysilane, n-propyltrimethoxysilane, diisopropyldimethoxysilane, isobutyltrimethoxysilane, diisobutyldimethoxysilane, n-propyltriethoxysilane, isobutyltriethoxysilane, n-hexyltrimethoxysilane, n-hexyltriethoxy Silane, cyclohexylmethyldimethoxysilane, n-octyltriethoxysilane, n-decyltrimethoxysilane, trifluoropropyltrimethoxy Orchids, methyltriphenoxysilane, hexamethyldisilazane can be used. These silane compounds (c) can be used alone or in combination of two or more.

  As the silane compound (c), a silane coupling agent such as an alkoxysilane compound generally containing an amino group, an epoxy group, a mercapto group, an isocyanato group, a hydroxyl group or the like can also be used. Specifically, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, N-β- (aminoethyl) -γ-aminopropyltrimethoxysilane, N-β- (aminoethyl) -γ-aminopropyltriethoxysilane, γ-aminodithiopropyltrihydroxysilane, γ- (polyethyleneamino) propyltrimethoxysilane, N-β- (aminopropyl) -γ-aminopropyl Amino group-containing alkoxysilane compounds such as methyldimethoxysilane, N- (trimethoxysilylpropyl) -ethylenediamine, γ-dibutylaminopropyltrimethoxysilane, γ-ureidopropyltriethoxysilane, γ-ureidopropyltrimethoxysilane, γ- (2-ureidoe Ureido group-containing alkoxysilane compounds such as aminopropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxy Epoxy group-containing alkoxysilane compounds such as silane, γ-mercaptopropyltrimethoxysilane, mercaptogroup-containing alkoxysilane compounds such as γ-mercaptopropyltriethoxysilane, γ-isocyanatopropyltriethoxysilane, γ-isocyanatopropyltrimethoxy Silane, γ-isocyanatopropylmethyldimethoxysilane, γ-isocyanatopropylmethyldiethoxysilane, γ-isocyanatopropylethyldimethoxysilane, γ-isocyanatopropylethyldiethoxysilane Emissions, isocyanato group-containing alkoxysilane compounds such as .gamma.-isocyanatopropyl trichlorosilane, .gamma.-hydroxypropyl trimethoxysilane, hydroxyl group-containing alkoxysilane compounds such as .gamma.-hydroxypropyl triethoxysilane can be used. These silane compounds (c) can be used alone or in combination of two or more.

<Curable resin>
The curable resin according to the present invention is a resin obtained by reacting polyester (a), silicone resin (b), and silane compound (c).

  In the curable resin composition, the polyester (a) is preferably 5 to 69% by weight, more preferably 10 to 60% by weight, and still more preferably 15 to 50% by weight. If it is less than 5% by weight, the adhesion may be lowered, and if it exceeds 69% by weight, the heat resistance may be insufficient.

  The silicone resin (b) is preferably 10 to 94% by weight, more preferably 20 to 88% by weight, and still more preferably 25 to 82% by weight in the curable resin composition. If it is less than 10% by weight, the heat resistance may be insufficient, and if it exceeds 95% by weight, the adhesion may be lowered.

  In the curable resin composition, the silane compound (c) is preferably 1 to 50% by weight, more preferably 2 to 45% by weight, and further preferably 3 to 40% by weight. If it is less than 1% by weight, the curability when heat-cured may be insufficient, and if it exceeds 50% by weight, the shrinkage of the coating film after heat-curing may be increased and the adhesion may be lowered. .

  The total amount of the polyester (a), the silicone resin (b), and the silane compound (c) is preferably 100% by weight.

  The number average molecular weight of the curable resin according to the present invention is preferably 500 to 100,000, more preferably 1,000 to 50,000, still more preferably 1,500 to 20,000, and 2,000 to 10,000. Particularly preferred is 2,500 to 8,000. If it is less than 500, the coating strength after thermosetting may be low, and if it exceeds 100,000, the varnish viscosity is high and the coatability may be deteriorated.

  The appearance of the curable resin according to the present invention is preferably colorless and transparent, and the b value in the color difference meter (L * a * b *) of the cured coating applied to the glass substrate is less than 1. preferable. Moreover, it is preferable that the Δb value before and after the heat treatment is less than 1 even after the heat treatment in the air at 300 ° C. for 30 minutes.

  The solvent used in the curable resin according to the present invention is not particularly limited as long as it is a solvent that dissolves the curable resin. For example, toluene, xylene, tetramethylbenzene, Solvesso 100, Solvesso 150, Solvesso 200 , Aromatic hydrocarbons such as tetralin, aliphatic hydrocarbons such as decalin, hexane, heptane, octane, decane, esters such as methyl acetate, ethyl acetate, isopropyl acetate, butyl acetate, methanol, ethanol, propanol, butanol , Alcohols such as 2-ethylhexanol, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, (di) ethylene glycol dimethyl ether, diethylene glycol monoethyl ether, dipropylene glycol diethyl ether , Various solvents such as dioxane, diethyl ether, tetrahydrofuran and other ethers, cellosolve acetate, ethyl cellosolve, cellosolve such as butyl cellosolve, carbitols such as carbitol, butyl carbitol, butyl carbitol acetate, etc. These solvents can be used alone or in combination of two or more. Among them, (di) ethylene glycol dimethyl ether, diethylene glycol monoethyl ether, dipropylene glycol diethyl ether, dioxane, diethyl ether, tetrahydrofuran and other ethers, cellosolve acetate, ethyl cellosolve, cellosolve such as butyl cellosolve, carbitol, butyl carbitol It is preferable to use a high boiling point solvent such as carbitols such as butyl carbitol acetate.

  Although it does not specifically limit as a manufacturing method of curable resin, First, polyester (a) and a silicone resin (b) are polymer 1 with unreacted silanol group or alkoxy group at 100-250 degreeC under normal pressure or pressure reduction. Polymerization is performed until 0.1 to 20 molecules remain per molecule, preferably 0.2 to 15, more preferably 0.5 to 10 molecules remain. Here, per polymer molecule means the weight (weight / number average molecular weight) per number average molecular weight of the polymer obtained from the polyester (a) and the silicone resin (b). Further, the silane compound (c) is added to the polymer, and 0.1 to 30 unreacted alkoxy groups per molecule of the resin remain at normal pressure or reduced pressure at 100 to 250 ° C., preferably 0.2 It can be obtained by polymerizing until -20, more preferably 0.5-6 remain. Here, per resin molecule means the weight (weight / number average molecular weight) per number average molecular weight of the resin obtained from the polymer and the silane compound (c).

  Although the preparation amount of the silicone resin (b) is not particularly limited, it is preferably 14 parts by weight or more, more preferably 33 parts by weight or more, and further preferably 50 parts by weight or more with respect to 100 parts by weight of the polyester (a). Moreover, 1880 weight part or less is preferable, 880 weight part or less is more preferable, and 540 weight part or less is further more preferable. If the amount is too small, the heat resistance may be insufficient. If the amount is too large, the adhesiveness may decrease.

  Although the preparation amount of the silane compound (c) is not particularly limited, it is preferably 1 part by weight or more, more preferably 3 parts by weight or more, and further preferably 6 parts by weight or more with respect to 100 parts by weight of the polyester (a). Moreover, 1000 weight part or less is preferable, 450 weight part or less is more preferable, and 260 weight part or less is further more preferable. If the amount is too small, the curability at the time of thermosetting may be insufficient. If the amount is too large, the shrinkage of the coating film after heat curing may increase and the adhesion may decrease.

  Control of the polymerization state (remaining number of unreacted silanol groups or alkoxy groups) when the polyester (a) and the silicone resin (b) are reacted can be carried out by the following formula.

Number of remaining silanols (pieces / molecule) = {hydroxyl equivalent of polyester (eq / t) × polyester charge (part by weight) + hydroxyl equivalent of silicone resin (eq / t) × silicone resin charge (part by weight)} / 10 ⁶ -2 × dehydration amount (parts by weight) / 18 / (total charge of polyester and silicone resin−dehydration amount (parts by weight)) × number average molecular weight of polymer / 2

Alkoxy remaining number (pieces / molecule) = {alkoxy group equivalent of silicone compound (eq / t) × charge amount of silicone compound (part by weight) / 10 ⁶ -dealcohol amount (part by weight) / molecular weight of desorbed alcohol} / (Total charge of polyester and silicone resin-dealcoholization amount (parts by weight)) × number average molecular weight of polymer

  Furthermore, the management of the polymerization state when the silane compound (c) is reacted (the number of remaining unreacted alkoxy groups as the curable resin) can be performed by the following formula.

Alkoxy remaining number (pieces / molecule) = {alkoxy group equivalent of silane compound (eq / t) × amount of silane compound charged (parts by weight) / 10 ⁶ -dealcohol amount (parts by weight) / molecular weight of eliminated alcohol} / (Total charge of polyester, silicone resin and silane compound-amount of dehydration-amount of dealcohol (part by weight)) x number average molecular weight of curable resin

The remaining number of unreacted alkoxy groups contained in the curable resin according to the present invention was obtained by dissolving the curable resin in deuterated chloroform and measuring ²⁹ Si-NMR, ¹ H-NMR, and ¹³ C-NMR. It can be calculated from the composition ratio identified from the peak area ratio. The number of remaining unreacted alkoxy groups is preferably 0.1 to 30 / molecule, more preferably 0.2 to 20 / molecule, and still more preferably 0.5 to 6 / molecule. Here, the number of remaining unreacted alkoxy groups (number / molecule) refers to the number of unreacted alkoxy groups per molecule of the curable resin (number average molecular weight of the curable resin). By satisfying the above range, it is possible to exhibit heat resistance capable of suppressing increase in impurities and coloring even when heat treatment is performed at 300 ° C. for 30 minutes while maintaining adhesion and curability. Become.

  The curable resin according to the present invention may contain a third component other than the polyester (a), the silicone resin (b), and the silane compound (c). Examples of the third component include an antioxidant, a light stabilizer, and a filler.

  When an antioxidant is used as the third component, it is effective when the curable resin according to the present invention is exposed to a high temperature and high humidity environment for a long period of time. 5-tris (3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate, 1,1,3-tri (4-hydroxy-2-methyl-5-tert-butylphenyl) butane, 1,1 -Bis (3-t-butyl-6-methyl-4-hydroxyphenyl) butane, 3,5-bis (1,1-dimethylethyl) -4-hydroxy-benzenepropanoic acid, pentaerythrityl tetrakis (3 , 5-Di-t-butyl-4-hydroxyphenyl) propionate, 3- (1,1-dimethylethyl) -4-hydroxy-5-methyl-benzenepropanoic acid, 3,9-bis 1,1-dimethyl-2-[(3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy] ethyl] -2,4,8,10-tetraoxaspiro [5.5] undecane, 1,3,5-trimethyl-2,4,6-tris (3 ′, 5′-di-t-butyl-4′-hydroxybenzyl) benzene, as a phosphorus system, 3,9-bis (p-nonylphenoxy) ) -2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane, 3,9-bis (octadecyloxy) -2,4,8,10-tetraoxa-3, 9-diphosphaspiro [5.5] undecane, tri (monononylphenyl) phosphite, triphenoxyphosphine, isodecyl phosphite, isodecylphenyl phosphite, diphenyl 2-ethane Ruhexyl phosphite, dinonylphenyl bis (nonylphenyl) ester phosphoric acid, 1,1,3-tris (2-methyl-4-ditridecyl phosphite-5-t-butylphenyl) butane, tris (2,4 -Di-t-butylphenyl) phosphite, pentaerythritol bis (2,4-di-t-butylphenyl phosphite), 2,2'-methylenebis (4,6-di-t-butylphenyl) 2-ethylhexyl Phosphite, bis (2,6-di-t-butyl-4-methylphenyl) pentaerythritol diphosphite, 4,4′-thiobis [2-t-butyl-5-methylphenol] bis [3 as thioether system -(Dodecylthio) propionate], thiobis [2- (1,1-dimethylethyl) -5-methyl -4,1-phenylene] bis [3- (tetradecylthio) -propionate], pentaerythritol tetrakis (3-n-dodecylthiopropionate), bis (tridecyl) thiodipropionate. Can be used alone or in combination. The amount used is preferably 0.01 to 10% by weight based on the curable resin. If it exceeds 10% by weight, it may adversely affect adhesion, heat resistance and the like.

  When a light stabilizer is used as the third component, it is effective when weather resistance is required for the curable resin according to the present invention. For example, a benzotriazole light stabilizer, a benzophenone light stabilizer, a hinder Amine light stabilizers, nickel light stabilizers, benzoate light stabilizers, and the like can be used as appropriate. Examples of the benzotriazole-based light stabilizer include 2- (3,5-di-tert-amyl-2′hydroxyphenyl) benzotriazole, 2- (2-hydroxy-5-tert-octylphenyl) benzotriazole, 2 -(2'-hydroxy-3'-tert-butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2- (2H-benzotriazol-2-yl) -p-cresol, 2- (2'- Hydroxy-5'-methylphenyl) -benzotriazole, 2,4-di-tert-butyl-6- (5-chlorobenzotriazol-2-yl) phenol, 2- [2-hydroxy-3,5-di ( 1,1-dimethylbenzyl)]-2H-benzotriazole and the like, but are not limited thereto. Examples of benzophenone light stabilizers include 2-hydroxy-4- (octyloxy) benzophenone, 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxybenzophenone, and 2-hydroxy-4. -Methoxy-benzophenone-5-sulfonic acid, 2-hydroxy-4-n-dodecyloxybenzophenone, bis (5-benzoyl-4-hydroxy-2-methoxyphenyl) methane, 2-2'-dihydroxy-4- Examples include, but are not limited to, methoxybenzophenone and 2,2′-dihydroxy-4,4′-dimethoxybenzophenone. Examples of hindered amine light stabilizers include bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, dimethyl succinate / 1- (2-hydroxyethyl) -4-hydroxy-2,2, 6,6-tetramethylpiperidine polycondensate, poly [{6- (1,1,3,3-tetramethylbutyl) amino-1,3,5-triazine-2,4-diyl} {(2,2 , 6,6-tetramethyl-4-piperidyl) imino} hexamethylene <2,2,6,6-tetramethyl-4-piperidyl) imino}], 1,3,5-tris (3,5-di-) tert-butyl-4-hydroxybenzyl) -s-triazine-2,4,6 (1H, 3H, 5H) trione, tris (4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl) -s- Triazine-2,4,6- [1H, 3H, 5H) Although trion etc. are mentioned, it is not limited to these. Nickel-based light stabilizers include [2,2′-thio-bis (4-tert-octylphenolate)]-2-ethylhexylamine-nickel- (II), nickel dibutyldithiocarbamate, [2 ′, 2 ′. -Thio-bis (4-tert-octylphenolate)] n-butylamine-nickel and the like, but is not limited thereto. Examples of the benzoate light stabilizer include, but are not limited to, 2,4-di-t-butylphenyl-3,5'-di-tert-butyl-4'-hydroxybenzoate. These light stabilizers can be used alone or in combination. The amount used is preferably 0.01 to 10% by weight based on the curable resin. If it is less than 0.01% by weight, the weather resistance effect may be poor, and if it exceeds 10% by weight, adhesion, heat resistance and the like may be adversely affected.

  By using a filler as the third component, further improvement in heat resistance can be expected. The filler is not particularly limited, and examples thereof include silica, talc, mica, barium sulfate, and indium oxide. These fillers can be used alone or in combination.

  EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples. In addition, evaluation of the characteristic value in each Example was performed with the following method.

(1) Measurement of resin composition Samples of polyester and curable resin were dissolved in deuterated chloroform, and ¹ H-NMR analysis was performed using NMR apparatus 400-MR manufactured by VARIAN. From the integral value ratio, molar ratio was obtained. Asked.

(2) Measurement of number average molecular weight Polyester and curable resin samples were dissolved and / or diluted with tetrahydrofuran so that the resin concentration was about 0.5% by weight, and made of polytetrafluoroethylene having a pore size of 0.5 μm. The molecular weight was measured by gel permeation chromatography (GPC) using a membrane filter as a measurement sample, tetrahydrofuran as a mobile phase, and a differential refractometer as a detector. The flow rate was 1 mL / min and the column temperature was 30 ° C. Showa Denko KF-802, 804L and 806L were used for the column. Monodisperse polystyrene was used as the molecular weight standard.

(3) Measurement of reduced viscosity (dl / g) 0.1 g of a polyester sample was dissolved in 25 cc of a mixed solvent of phenol / tetrachloroethane (weight ratio 6/4) and measured at 30 ° C.

(4) Measurement of acid value 0.2 g of a polyester sample was dissolved in 40 ml of chloroform and titrated with 0.01 N potassium hydroxide ethanol solution, and the equivalent (eq / t) per 10 ⁶ g of carboxyl group-containing resin was determined. Asked. Phenolphthalein was used as an indicator.

(5) Preparation of test piece On one side of a glass plate (125 mm × 125 mm × 1 mm), a curable resin is applied with a wire bar so that the film thickness after drying becomes 10 to 20 μm, and thermosetting conditions 160 ° C. × 30 Heat treatment was performed using a hot air dryer as a minute, and this was used as a test piece (hereinafter referred to as a test piece).

<Curing property>
A curable resin is applied to a glossy surface of an electrolytic copper foil having a thickness of 18 μm with a wire bar so that the thickness after drying becomes 10 to 20 μm, and heat treatment is performed using a hot air dryer under a heat curing condition of 160 ° C. for 30 minutes. The laminated body which formed the cured film was obtained. This laminate was cut into a size of 2.5 cm × 10 cm, immersed in tetrahydrofuran (THF) for 60 minutes, the weight before and after immersion was measured, and the residual ratio of the weight was taken as the gel fraction.
Gel fraction (% by weight) = [(weight after immersion in THF−weight of electrolytic copper foil) / (weight before immersion in THF−weight of electrolytic copper foil)] × 100
Judgment criteria ○: 60% or more △: 40% or more and less than 60% ×: less than 40%

<Adhesion>
In accordance with JIS-K5600, 100 test pieces of 100 mm 1 mm grids were made, and a peel test was performed with cello tape to observe the peeled state of the grids.
Criteria ○: No peeling at 100/100 Δ: 70 to 99/100
X: 0 to 69/100

<Heat resistance>
The test piece was heat-treated using a hot air dryer under heat resistance evaluation conditions of 300 ° C. for 30 minutes. Using a colorimetric color difference meter Color Meter ZE 2000 (manufactured by Nippon Denshoku Industries Co., Ltd.), the test piece before and after the heat treatment was measured from the curable resin layer side of the test piece according to the method described in JIS-Z8722, and L * a * B * Evaluation was based on the Δb value when expressed in the color system. The Δb value refers to the difference between the b values before and after the heat resistance test (b value after the test−b value before the test).
Criteria ○: Δb value less than 1 Δ: Δb value 1 or more and less than 2 ×: Δb value 2 or more

Synthesis example of polyester (a) by direct polymerization method (1)
In a 10 L four-necked flask equipped with a stirrer, a condenser and a thermometer, 697 parts by weight of terephthalic acid, 1510 parts by weight of isophthalic acid, 134 parts by weight of trimellitic anhydride, 1042 parts by weight of ethylene glycol, 1165 parts by weight of neopentyl glycol, as a catalyst Charged 0.95 parts by weight of tetra-n-butyl titanate (hereinafter sometimes abbreviated as TBT) (0.02 mol% with respect to the total acid components) and gradually raised the temperature to 240 ° C. over 4 hours. The esterification reaction was carried out. Next, the system is gradually depressurized, the initial polymerization is performed by reducing the pressure to 10 mmHg over 30 minutes, the temperature is raised to 250 ° C., and the latter polymerization is performed for 10 minutes under a vacuum of 1 mmHg or less. An inventive polyester (Synthesis Example (1)) was obtained. The number average molecular weight of the obtained polyester was 3,000, the reduced viscosity was 0.17 dl / g, and the acid value was 20 eq / t.

Synthesis Examples (2) and (3) of Polyester (a) by Direct Polymerization Method, Comparative Synthesis Examples (1) and (2)
Polyester of the present invention as shown in Table 1 (Synthesis Examples (2) and (3), Comparative Synthesis Example) by direct polymerization method as in Synthesis Example (1), but changing the charged composition. (1) and (2)) were produced.

Example of synthesis of polyester (a) by direct polymerization method (4)
In a 10 L four-necked flask equipped with a stirrer, a condenser and a thermometer, 1955 parts by weight of isophthalic acid, 191 parts by weight of adipic acid, 1531 parts by weight of 2-methyl-1,3-propanediol, 817 parts by weight of neopentyl glycol, 175 parts by weight of methylolpropane and 0.89 part by weight of tetra-n-butyl titanate (hereinafter sometimes abbreviated as TBT) as a catalyst (0.02 mol% based on the total acid components) were charged over 4 hours. The esterification reaction was performed while gradually raising the temperature to 240 ° C. Subsequently, the pressure in the system was gradually reduced, the initial polymerization was carried out by reducing the pressure to 10 mmHg over 30 minutes, the temperature was raised to 250 ° C., and the latter polymerization was carried out for 12 minutes under a vacuum of 1 mmHg or less. Next, after returning to normal pressure, the mixture was cooled to 220 ° C. over 30 minutes, added with 50 parts by weight of trimellitic anhydride, and reacted at 220 ° C. for 30 minutes to obtain the polyester of the present invention (Synthesis Example (4)). Obtained. The number average molecular weight of the obtained polyester was 4,000, the reduced viscosity was 0.20 dl / g, and the acid value was 250 eq / t.

Comparative synthesis example of polyester (a) by direct polymerization method (2)
As in Synthesis Example (4), the polyester of the present invention (Comparative Synthesis Example (2)) having a resin composition as shown in Table 1 was produced by a direct polymerization method except that the charged composition was changed.

Synthesis example of polyester (a) by transesterification method (5)
In a 10 L four-necked flask equipped with a stirrer, a condenser and a thermometer, 820 parts by weight of dimethyl terephthalate, 1777 parts by weight of dimethyl isophthalate, 135 parts by weight of trimellitic anhydride, 1048 parts by weight of ethylene glycol, 1172 parts by weight of neopentyl glycol, The catalyst was charged with 0.96 parts by weight of tetra-n-butyl titanate (hereinafter sometimes abbreviated as TBT) (0.02 mol% based on the total acid components) and gradually increased to 220 ° C. over 4 hours. The esterification reaction was carried out while warming. Next, the system is gradually depressurized, the initial polymerization is performed by reducing the pressure to 10 mmHg over 30 minutes, the temperature is raised to 250 ° C., and the latter polymerization is performed for 10 minutes under a vacuum of 1 mmHg or less. An inventive polyester (Synthesis Example (5)) was obtained. There is no difference from the performance of Synthesis Example (1) obtained by the direct polymerization method, and the composition and characteristic values are shown in Table 1.

Example of synthesis of curable resin (6)
242 parts by weight of butyl carbitol acetate was added to a 1 L four-necked flask equipped with a stirrer, a Dean-Stark apparatus, and a thermometer, and heated to 80 ° C. Next, 66 parts by weight of the polyester of Synthesis Example (1) and 210 parts by weight of 217 FLAKE RESIN (silicone resin made by Toray Dow Corning, silanol group content 6% by weight) were added, stirred and dissolved. Thereafter, the temperature was gradually raised to 200 ° C. over 1 hour to carry out a dehydration reaction. After confirming that the amount of distilled water was 1.36 parts by weight with a reaction rate of 45%, the temperature was lowered to 150 ° C. over 30 minutes. Next, 24 parts by weight of n-decyltrimethoxysilane was added, and a dealcoholization reaction was performed at 150 ° C. After confirming that the amount of methanol distilled out was 3.00 parts by weight with a reaction rate of 34%, the mixture was cooled to room temperature over 1 hour, butyl carbitol acetate was added, and the solid content was 50% by weight. To obtain a curable resin of the present invention (Synthesis Example (6)). The number average molecular weight of the obtained curable resin was 4,000, and the number of remaining unreacted alkoxy groups was 2.4 / molecule.

Synthesis examples (7) to (11) of curable resins, comparative synthesis examples (5), (6), (8)
In the same manner as in Synthesis Example (6), except that the charge composition was changed, and the curable resins of the present invention (Synthesis Examples (7) to (11) and Comparative Synthesis Example (5) whose resin composition is shown in Table 2 were used. ), (6), (8)). In Comparative Synthesis Example (5), the resin layer and the solvent layer were separated and could not be produced.

Comparative synthesis example (3)
To a 1 L four-necked flask equipped with a stirrer, a Dean-Stark apparatus, and a thermometer, 243 parts by weight of butyl carbitol acetate was added and heated to 80 ° C. Next, 42 parts by weight of polyester of Synthesis Example (2), 69 parts by weight of polyester of Synthesis Example (3), Z-6018 (silicone resin manufactured by Toray Dow Corning, silanol group content 6% by weight) 99 parts by weight, 233 FLAKE 90 parts by weight of RESIN (silicone resin manufactured by Toray Dow Corning, silanol group content: 6% by weight) was added and stirred to dissolve. Thereafter, the temperature was gradually raised to 200 ° C. over 1 hour to carry out a dehydration reaction. After confirming that the amount of distilled water was 2.6 parts by weight, it was cooled to room temperature over 1.5 hours, and butyl carbitol acetate was added to adjust the solid content to 50% by weight. The resin of Example (3) was obtained. The number average molecular weight of the obtained resin was 5,000.

Comparative synthesis example (4)
105 parts by weight of butyl carbitol acetate was added to a 1 L four-necked flask equipped with a stirrer, Dean Stark apparatus, and thermometer, and heated to 80 ° C. Next, 117 parts by weight of 217 FLAKE RESIN (silicone resin made by Toray Dow Corning, silanol group content: 6% by weight) and 13 parts by weight of phenyltrimethoxysilane were added and stirred to dissolve. Thereafter, the temperature was raised to 150 ° C. over 30 minutes to carry out a dealcoholization reaction. After confirming that the amount of distilled methanol was 2.15 parts by weight, it was cooled to room temperature over 1 hour, and butyl carbitol acetate was added to adjust the solid content to 50% by weight. The resin 2) was obtained. The number average molecular weight of the obtained resin was 2,500.

Comparative synthesis example (7)
To a 1 L four-necked flask equipped with a stirrer, a Dean-Stark apparatus, and a thermometer, 244 parts by weight of butyl carbitol acetate was added and heated to 80 ° C. Next, 66 parts by weight of the polyester of Synthesis Example (1) and 210 parts by weight of 217 FLAKE RESIN (silicone resin made by Toray Dow Corning, silanol group content 6% by weight) were added, stirred and dissolved. Thereafter, the temperature was gradually raised to 200 ° C. over 1 hour to carry out a dehydration reaction. After confirming that the amount of distilled water was 1.36 parts by weight, the temperature was lowered to 150 ° C. over 30 minutes. Next, after adding 24 parts by weight of tetraethoxysilane, the mixture was cooled to room temperature over 1 hour, butyl carbitol acetate was added to adjust the solid content to 50% by weight, and a resin of Comparative Synthesis Example (7) was obtained. The number average molecular weight of the obtained resin was 2,000.

Z-6018: Toray Dow Corning Co., Ltd. silicone resin, number average molecular weight 2,000, silanol group content 6% by weight
217 FLAKE RESIN: Toray Dow Corning Co., Ltd. silicone resin, number average molecular weight 2,000, silanol group content 6% by weight
220 FLAKE RESIN: silicone resin manufactured by Toray Dow Corning Co., Ltd., number average molecular weight 3,000, silanol group content 6% by weight
233 FLAKE RESIN: silicone resin manufactured by Toray Dow Corning Co., Ltd., number average molecular weight 3,000, silanol group content 6% by weight
3074 INTERMEDIATE: Silicone resin manufactured by Toray Dow Corning Co., Ltd., number average molecular weight 1,400, methoxy group content 17% by weight

Production Example of Resin Varnish The polyester of Synthesis Example (1) was dissolved in propylene glycol monomethyl ether acetate to prepare a resin varnish having a solid content of 50% by weight.

Example (1)
The resin varnish of Synthesis Example (6) was applied and heat-treated by the method described above to obtain a test piece of the coated glass plate of the present invention. The results of evaluating the test pieces are shown in Table 3.

Examples (2) to (6), Comparative Examples (1) to (6)
In the same manner as in Example (1), coating and heat treatment were performed by the method described above to obtain a test piece of the coated glass plate of the present invention. The results of evaluating the test pieces are shown in Table 3.

  As is apparent from Table 3, the coating film obtained from the curable resin of the present invention has excellent curability, adhesion, and heat resistance.

  Since the curable resin according to the present invention is excellent in curability, heat resistance and adhesion, it is suitable for various binder applications. In particular, it is suitable for binder applications for high heat-resistant frame ink.

Claims (6)

A polyester (a) having a number average molecular weight of 500 to 10,000 and an acid value of 300 eq / t or less, a silicone resin (b), and a silane compound (c) represented by the following formula (1) are reacted. A curable resin containing 0.1 to 30 unreacted alkoxy groups per molecule.

(In the formula, each R ¹ is independently a group having 1 to 20 carbon atoms, which may have a straight chain structure, a branched structure, a cyclic structure, and / or a hetero atom, and R ² is , Each independently a hydrocarbon group optionally having a straight chain structure, a branched structure, or a cyclic structure having 1 to 20 carbon atoms, n is an integer of 0 to 3)   The curable resin according to claim 1, wherein the silicone resin (b) has a number average molecular weight of 500 to 5,000, and contains 1 to 20% by weight of a silanol group and / or an alkoxy group. The curable resin according to claim 1 or 2, wherein the silicone resin (b) contains any one or more of structural units represented by the following formulas (2) to (4).

(In the formula, each R ³ is independently a hydrocarbon group having 1 to 20 carbon atoms, which may have a linear structure, a branched structure, or a cyclic structure, and each R ⁴ is independently And a hydrocarbon group which may have a hydrogen atom or a straight chain structure having 1 to 20 carbon atoms, a branched structure, or a cyclic structure)   The ink containing the curable resin of any one of Claims 1-3.   The adhesive agent containing the curable resin of any one of Claims 1-3. It is a manufacturing method of curable resin in any one of Claims 1-3, Comprising: Polyester (a) and a silicone resin (b) are 0.1 to 0.1 molecule per molecule of unreacted silanol groups or alkoxy groups. A method for producing a curable resin, in which after polymerization is performed until 20 remain, the silane compound (c) is further polymerized until 0.1 to 30 unreacted alkoxy groups remain per molecule.

(In the formula, each R ¹ is independently a group having 1 to 20 carbon atoms, which may have a straight chain structure, a branched structure, a cyclic structure, and / or a hetero atom, and R ² is , Each independently a hydrocarbon group optionally having a straight chain structure, a branched structure, or a cyclic structure having 1 to 20 carbon atoms, n is an integer of 0 to 3)