Modified polyisocyanate, coating and painting metal material

Abstract

To provide a modified polyisocyanate having high adhesive property to a non-ferrous metal and applicable to a one-coat coating material.SOLUTION: A modified polyisocyanate is a reaction product which has as the raw material, components containing an alkoxysilane (a1) having a primary amino group, an unsaturated carboxylic acid alkyl ester (a2) or a saturated carboxylic acid alkyl ester (a3), and a polyisocyanate (a4). The unsaturated carboxylic acid alkyl ester (a2) is at least one kind selected from the group consisting of a branched alkyl ester (a2-1) of an unsaturated dicarboxylic acid, and a branched alkyl ester (a2-2) which may contain a hetero atom of an unsaturated monocarboxylic acid or has a cyclic structure. A production method of the modified polyisocyanate, and a coating containing the same are also provided.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a modified polyisocyanate, a coating, and a coated metal material.

Background Art

[0002] Polyisocyanate compounds are highly reactive substances and are widely used as raw materials for chemical products such as polyurethane foams, sealants, adhesives, and paints. In recent years, modified polyisocyanates with various modifications have been developed according to the functions required for these chemical products.

[0003] For example, Patent Document 1 describes a silyl-isocyanate obtained by reacting a polyisocyanate with a silane starting material. This silyl-isocyanate is disclosed to have good adhesion to glass and be useful as a fixing agent for use in combination with a polyurethane resin.

[0004] Also, Patent Document 2 describes a reaction product of an amino-alkylalkoxysilane and a maleic acid ester or a fumaric acid ester, and this reaction product is disclosed to be useful as a modifier for polyisocyanates.

[0005] Furthermore, Patent Document 3 discloses a crosslinkable silyl group-containing urethane-based resin mixture obtained by reacting a compound containing two or more active hydrogens and one or more crosslinkable silyl groups in the molecule with an acrylic compound and / or a methacrylic compound to obtain a compound containing one or more active hydrogens and one or more crosslinkable silyl groups in the molecule, and reacting this with an isocyanate group-containing urethane prepolymer obtained by reacting an organic polyisocyanate and a polymeric polyol under conditions of an excess of isocyanate groups with respect to the active hydrogens.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

[0007] By the way, in recent years, the development of direct-to-metal coating has been expected. Direct-to-metal coating refers to a coating that forms a protective coating having both corrosion resistance and weather resistance by simply applying one type of paint directly to a metal surface. As a coating on metal, a multi-layer coating finish is usually performed in which a primer paint for suppressing rust is applied and a topcoat paint having excellent weather resistance and finish is applied thereon. On the other hand, according to direct-to-metal coating, desired performance can be obtained with a single-layer coating finish, so there is an advantage in achieving process reduction and shortening of the construction period. However, generally, the corrosion resistance and weather resistance of a coating film are in an inverse relationship, and it is difficult to achieve both. In addition, non-ferrous metals have a problem that the coating film adheres less easily than iron and the coating film is easily peeled off, and it is extremely difficult to develop a paint having excellent adhesion to non-ferrous metals in addition to corrosion resistance and weather resistance.

[0008] Although various modified polyisocyanates are disclosed in the above Patent Documents 1 to 3, modified polyisocyanates applicable to a one-coat paint having high adhesion to non-ferrous metals are not disclosed. [Means for Solving the Problems]

[0009] The inventors of the present invention have intensively studied the above problems. As a result, they have arrived at using an alkoxysilane having a primary amino group and a specific unsaturated carboxylic acid alkyl ester or a modified polyisocyanate modified with a saturated carboxylic acid alkyl ester. And it has been found that this modified polyisocyanate is excellent as a metal adhesion material, and a coating containing the same is excellent in adhesion not only to iron but also to non-ferrous metals.

[0010] That is, the present invention relates to Item 1 A modified polyisocyanate for use together with an active hydrogen-containing compound as a curing agent for a coating, which is a reaction product using as raw materials components containing an alkoxysilane (a1) having a primary amino group, an unsaturated carboxylic acid alkyl ester (a2) or a saturated carboxylic acid alkyl ester (a3), and a polyisocyanate (a4), wherein the unsaturated carboxylic acid alkyl ester (a2) is a branched alkyl ester (a2-1) of an unsaturated dicarboxylic acid, and a branched alkyl ester which may contain a hetero atom of an unsaturated monocarboxylic acid or an alkyl ester having a cyclic structure (a2-2) and is at least one selected from the group consisting of a modified polyisocyanate. Item 2 The modified polyisocyanate according to Item 1, wherein the alkoxysilane (a1) having a primary amino group is a compound represented by the following formula (1).

[0011]

Chemical formula

[0012] In formula (1), R 1 and R 2 are the same or different and are a linear or branched alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, alkynyl group, cycloalkynyl group, aryl group or heteroaryl group having 1 to 18 carbon atoms, which may be substituted, and R3 is a linear or branched alkylene group having 1 to 8 carbon atoms, preferably 1 to 5 carbon atoms, and n is an integer of 0 to 2. Item 3 The modified polyisocyanate according to Item 1 or 2, wherein the branched alkyl ester (a2-1) of the unsaturated dicarboxylic acid is a compound represented by the following formula (2). R 4 O-C(=O)-HC=CH-C(=O)-OR 5 (2)

[0013] In formula (2), R 4 and R 5 are the same or different and are branched alkyl groups having 1 to 8 carbon atoms. Item 4 The modified polyisocyanate according to Item 1 or 2, wherein the branched alkyl ester (a2-2) of the unsaturated monocarboxylic acid which may contain a hetero atom or the alkyl ester having a cyclic structure is a compound represented by the following formula (3). H2C=CH-C(=O)-OR 6 (3)

[0014] In formula (3), R 6 represents a branched alkyl group having 3 to 18 carbon atoms or an alkyl group having a cyclic structure, or a group obtained by incorporating a hetero atom (for example, an oxygen atom, a nitrogen atom, a sulfur atom) into a branched or cyclic alkyl group having 1 to 18 carbon atoms or an arylalkyl group. Item 5 The modified polyisocyanate according to Item 1 or 2, wherein the saturated carboxylic acid alkyl ester (a3) is a compound represented by the following formula (4). R 7 -C(=O)-OR 8 (4)

[0015] In formula (4), R 7 and R 8is an alkyl group having 1 to 18 carbon atoms and not having an unsaturated group, which may be the same or different, or a group formed by including a hetero atom, such as an oxygen atom, a nitrogen atom, or a sulfur atom, in a molecule of an alkyl group or an arylalkyl group having 1 to 18 carbon atoms and not having an unsaturated group. Item 6 The modified polyisocyanate according to any one of Items 1 to 4, having a structure in which the secondary amino group of the alkoxysilane N-position modified product formed by the addition of the primary amino group of the alkoxysilane (a1) to the unsaturated carbon-carbon bond of the unsaturated carboxylic acid alkyl ester (a2) is added to the isocyanate group of the polyisocyanate (a4). Item 7 The modified polyisocyanate according to any one of Items 1 or 2 and 5, having a structure in which the secondary amide group of the alkoxysilane N-position modified product formed by the reaction of the primary amino group of the alkoxysilane (a1) with the ester group of the saturated carboxylic acid alkyl ester (a3) is added to the isocyanate group of the polyisocyanate (a4). Item 8 The modified polyisocyanate according to Item 6, wherein the unsaturated carboxylic acid alkyl ester (a2) is a branched alkyl ester (a2-1) of an unsaturated dicarboxylic acid, and the alkoxysilane N-position modified product is a compound represented by the following formula (5).

[0016]

Chemical formula

[0017] In formula (5), R 1 and R 2 are the same or different and are a linear or branched alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an alkynyl group, a cycloalkynyl group, an aryl group, or a heteroaryl group having 1 to 18 carbon atoms, which may be substituted, and R 3 is a linear or branched alkylene group having 1 to 8 carbon atoms, preferably 1 to 5 carbon atoms, and R 4 and R 5is the same or different and is a branched alkyl group having 1 to 8 carbon atoms, and n is an integer of 0 to 2. Item 9 The modified polyisocyanate according to any one of Items 6 to 8, wherein the reaction ratio of the alkoxysilane N-position modified product having the secondary amino group and the polyisocyanate (a4) is such that the secondary amino group is 40 mol or less with respect to 100 mol of the isocyanate group. Item 10 The modified polyisocyanate according to Item 6, wherein the unsaturated carboxylic acid alkyl ester (a2) is a branched alkyl ester which may contain a hetero atom of an unsaturated monocarboxylic acid or an alkyl ester having a cyclic structure (a2-2), and the alkoxysilane N-position modified product is a compound represented by the following formula (6).

[0018] [Chemical formula]

[0019] In formula (6), R 1 and R 2 are the same or different and are a linear or branched alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, alkynyl group, cycloalkynyl group, aryl group or heteroaryl group having 1 to 18 carbon atoms which may be substituted, R 3 is a linear or branched alkylene group having 1 to 8 carbon atoms, preferably 1 to 5 carbon atoms, R 6 is an alkyl group having a branched or cyclic structure which may contain a hetero atom having 3 to 18 carbon atoms or a group obtained by incorporating a hetero atom such as an oxygen atom, nitrogen atom or sulfur atom into a molecule of an alkyl group or arylalkyl group having a branched or cyclic structure having 1 to 18 carbon atoms, and n is an integer of 0 to 2. Item 11 The modified polyisocyanate according to any one of Items 6 to 10, wherein the reaction ratio of the mixture containing the alkoxysilane N-position modified product having the secondary amino group and the polyisocyanate (a4) is such that the total number of moles of the primary amino group and the secondary amino group is 40 mol or less with respect to 100 mol of the isocyanate group. Item 12 The modified polyisocyanate according to item 7, wherein the alkoxysilane N-position modified product obtained by reacting an alkoxysilane (a1) with a saturated carboxylic acid alkyl ester (a3) is an N-position acyl modified product represented by the following formula (7) having a secondary amide group.

[0020]

Chemical formula

[0021] In formula (7), R 1 and R 2 are the same or different and are a linear or branched alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, alkynyl group, cycloalkynyl group, aryl group or heteroaryl group having 1 to 18 carbon atoms, which may be substituted, n is an integer of 0 to 2, R 3 is a linear or branched alkylene group having 1 to 8 carbon atoms, preferably 1 to 5 carbon atoms, and R 7 is an alkyl group having 1 to 18 carbon atoms without an unsaturated group, or a group obtained by including a heteroatom, such as an oxygen atom, a nitrogen atom, or a sulfur atom, in the molecule of an alkyl group having 1 to 18 carbon atoms and having no unsaturated group. Item 13 Step (1) of reacting an alkoxysilane (a1) having a primary amino group and a saturated carboxylic acid alkyl ester (a3) in the presence of a basic catalyst, Step (2) of adding an acidic compound, Step (3) of removing part or all of the alcohol produced as a by-product to prepare an intermediate containing an N-position acyl modified product represented by the following formula (7), Step (4) of reacting the intermediate with a polyisocyanate (a4) The modified polyisocyanate according to item 1 or 12, which is produced by the above process.

[0022]

Chemical formula

[0023] In formula (7), R1 and R 2 are the same or different and are a linear or branched alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, alkynyl group, cycloalkynyl group, aryl group or heteroaryl group having 1 to 18 carbon atoms, which may be substituted, and R 3 is a linear or branched alkylene group having 1 to 8 carbon atoms, preferably 1 to 5 carbon atoms, n is an integer of 0 to 2, and R 7 is an alkyl group having 1 to 18 carbon atoms and having no unsaturated group, or is a group having 1 to 18 carbon atoms and containing a hetero atom, such as an oxygen atom, a nitrogen atom or a sulfur atom, in the molecule of the alkyl group and having no unsaturated group. Item 14 The modified polyisocyanate according to Item 12 or 13, wherein the reaction ratio of the N-position acyl-modified product and the polyisocyanate (a4) is such that the total number of moles of the secondary amide group and the primary amino group is 40 moles or less per 100 moles of isocyanate groups. Item 15 Step (1) of reacting an alkoxysilane (a1) having a primary amino group and a saturated carboxylic acid alkyl ester (a3) in the presence of a basic catalyst, Step (2) of adding an acidic compound, Step (3) of removing part or all of the alcohol produced as a by-product to prepare an intermediate containing an N-position acyl-modified product represented by the following formula (7), Step (4) of reacting the intermediate with a polyisocyanate (a4) The method for producing a modified polyisocyanate according to Item 1, which comprises

[0024]

Chemical formula

[0025] In formula (7), R 1 and R 2is the same as or different from, and is a linear or branched alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, alkynyl group, cycloalkynyl group, aryl group or heteroaryl group having 1 to 18 carbon atoms, which may be substituted, R 3 is a linear or branched alkylene group having 1 to 8 carbon atoms, preferably 1 to 5 carbon atoms, n is an integer of 0 to 2, R 7 is an alkyl group having 1 to 18 carbon atoms and having no unsaturated group, or a group formed by including a heteroatom, such as an oxygen atom, a nitrogen atom, or a sulfur atom, in the molecule of an alkyl group having 1 to 18 carbon atoms, and having no unsaturated group. Item 16 The unsaturated carboxylic acid alkyl ester (a2) is a branched alkyl ester which may contain a heteroatom of an unsaturated monocarboxylic acid or an alkyl ester (a2-2) having a cyclic structure, and the reaction of the alkoxysilane N-position modified product having the secondary amino group and the polyisocyanate (a4) is carried out in the coexistence of an alkoxysilane (a1) having a primary amino group and a tertiary amino group-containing compound represented by the following formula (8) which is a by-product. The modified polyisocyanate according to Item 6.

[0026] [Chemical formula]

[0027] In formula (8), R 1 and R 2 are the same as or different from each other, and are a linear or branched alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, alkynyl group, cycloalkynyl group, aryl group or heteroaryl group having 1 to 18 carbon atoms, which may be substituted, R 3 is a linear or branched alkylene group having 1 to 8 carbon atoms, preferably 1 to 5 carbon atoms, R 6 is an alkyl group having a branched or cyclic structure which may contain a heteroatom having 3 to 18 carbon atoms, or a group formed by including a heteroatom, such as an oxygen atom, a nitrogen atom, or a sulfur atom, in the molecule of an alkyl group having a branched or cyclic structure having 1 to 18 carbon atoms or an arylalkyl group, and n is an integer of 0 to 2. Item 17 The modified polyisocyanate according to any one of Items 1, 2, 5, 7, 12, 13, and 14, wherein the saturated carboxylic acid alkyl ester (a3) is an alkyl ester of a carboxylic acid having a linear structure and having two or more hydrogen atoms at the α-position, or an alkyl ester of a carboxylic acid having a branched structure and having two hydrogen atoms at the α-position. Item 18 The method for producing a modified polyisocyanate according to Item 15, wherein the saturated carboxylic acid alkyl ester (a3) is an alkyl ester of a carboxylic acid having a linear structure and having two or more hydrogen atoms at the α-position. Item 19 A coating containing an active hydrogen-containing compound and the modified polyisocyanate according to any one of Items 1 to 14, 16, and 17. Item 20 The coating according to Item 19, wherein the active hydrogen-containing compound contains an acrylic polyol and / or a bisaspartic acid ester derivative. Item 21 The coating according to Item 19 or 20, further comprising at least one selected from the group consisting of a rust inhibitor, a catalyst, a coloring pigment, and a extender pigment. Item 22 The coating according to any one of Items 19 to 21, which is a one-coat paint. Item 23 A protective coating film formed by curing the coating according to any one of Items 19 to 22. Item 24 A coated metal material, wherein the protective coating film according to any one of Items 19 to 22 is formed on a metal substrate. Regarding.

Advantages of the Invention

[0028] In this specification, the singular forms (a, an, the, etc.) shall include the singular and plural, unless otherwise expressly stated in this specification or clearly inconsistent in context. The modified polyisocyanate of the present invention is excellent in storage stability and can be used as an agent for improving the adhesion of coatings to metals. By using this modified polyisocyanate, a coating capable of forming a protective coating film excellent in adhesion not only to iron but also to non-ferrous metals can be obtained.

Embodiments for Carrying Out the Invention

[0029] The modified polyisocyanate of the present invention is a reaction product obtained from components including an alkoxysilane (a1) having a primary amino group, an unsaturated carboxylic acid alkyl ester (a2) or a saturated carboxylic acid alkyl ester (a3), and a polyisocyanate (a4) as raw materials.

[0030] The raw materials of the modified polyisocyanate of the present invention include, as the carboxylic acid alkyl ester, an unsaturated carboxylic acid alkyl ester (a2) or a saturated carboxylic acid alkyl ester (a3). In a first embodiment, the present invention provides a modified polyisocyanate using an unsaturated carboxylic acid alkyl ester (a2) as a raw material (denoted as modified polyisocyanate (X)), and a second aspect provides a modified polyisocyanate using a saturated carboxylic acid alkyl ester (a3) as a raw material (denoted as modified polyisocyanate (Y)).

[0031] When using an unsaturated carboxylic acid alkyl ester (a2) as the carboxylic acid alkyl ester, the unsaturated carboxylic acid alkyl ester (a2) is a branched alkyl ester (a2-1) of an unsaturated dicarboxylic acid, and a branched alkyl ester optionally containing a heteroatom of an unsaturated monocarboxylic acid or an alkyl ester having a cyclic structure (a2-2) and is at least one selected from the group consisting of.

[0032] In the present invention, by using the unsaturated carboxylic acid alkyl ester (a2) or the saturated carboxylic acid alkyl ester (a3) as a modifier, a modified polyisocyanate that can be stably diluted in an organic solvent and has excellent storage stability can be obtained, and it is possible to form a protective coating film having excellent adhesion to various metal substrates together with an active hydrogen group-containing compound described later.

[0033] In the present invention, when the group in the general formula such as formula (1) and formula (5) is substituted, unless otherwise indicated, examples of the substituent include an alkyl group, an alkenyl group, an alkynyl group, an alkoxy group, an amino group, a monoalkylamino group, a dialkylamino group, a carboxyl group, a hydroxyl group, a hydroxyalkyl group, a hydroxyalkoxy group, an aryl group, an aryloxy group, a heteroaryl group, and the like.

[0034] In the present invention, unless otherwise specified, examples of each substituent include the following: The alkyl group, unless otherwise specified, refers to a linear, branched or cyclic saturated hydrocarbon group. The number of carbon atoms of the alkyl group is not particularly limited, and examples thereof include 1 to 18, 1 to 10, 1 to 8, 1 to 6, 1 to 4, 1 to 3, and the like. Examples of such an alkyl group include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, an i-butyl group, a t-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, an n-nonyl group, an n-decyl group, an n-undecyl group, an n-dodecyl group, an n-tridecyl group, an n-tetradecyl group, an n-pentadecyl group, an n-hexadecyl group, an n-heptadecyl group, an n-octadecyl group, a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, and the like. Examples of the cycloalkyl group include cyclic hydrocarbon groups in which all carbon-carbon bonds are single bonds. The number of carbon atoms is, for example, 3 to 8. More specifically, examples of the cycloalkyl group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, and the like. Examples of the hydroxyalkyl group include groups in which one or more (for example, 1 to 3, 1 to 2, 1) hydroxyl groups are substituted for the above-described alkyl group. Examples of the alkoxy group include alkoxy in which the above-described alkyl moiety is the above-described alkyl group. Examples of the hydroxyalkoxy group include groups in which one or more (for example, 1 to 3, 1 to 2, 1) hydroxyl groups are substituted for the above-described alkoxy group. The alkenyl group represents a linear or branched hydrocarbon group having a carbon-carbon double bond. The number of carbon atoms of the alkenyl group is not particularly limited and is, for example, 2 to 18, 2 to 10, 2 to 8, 2 to 6, 2 to 4, 2 to 3, and the like. The number of carbon-carbon double bonds in the alkenyl group is not limited, but is, for example, 1 to 2, preferably 1. Examples of such an alkenyl group include a vinyl group, a 1-propenyl group, a 2-propenyl group, a 1-butenyl group, a 1-pentenyl group, a 1,4-pentadienyl group, a 1-hexenyl group, a 1-heptenyl group, a 1-octenyl group, a 1-nonenyl group, a 1-decenyl group, a 2-undecenyl group, a 3-dodecenyl group, a 1-tridecenyl group, a 2-tetradecenyl group, a 3-pentadecenyl group, a 1-hexadecenyl group, a 2-heptadecenyl group, a 3-octadecenyl group, and the like. The alkynyl group represents a linear or branched hydrocarbon group having a carbon-carbon triple bond. The number of carbon atoms in the alkynyl group is not particularly limited, and examples thereof include 2 to 18, 2 to 10, 2 to 8, 2 to 6, 2 to 4, 2 to 3, and the like. The number of carbon-carbon triple bonds in the alkynyl group is not limited, and examples thereof include 1 to 2, preferably 1. Examples of such an alkynyl group include ethynyl group, 1-propynyl group, 2-propynyl group, 1-butynyl group, 1-pentynyl group, 1,4-pentadiynyl group, 1-hexynyl group, 1-heptynyl group, 1-octynyl group, 1-nonynyl group, 1-decynyl group, 2-undecynyl group, 3-dodecynyl group, 1-tridecynyl group, 2-tetradecynyl group, 3-pentadecynyl group, 1-hexadecynyl group, 2-heptadecynyl group, 3-octadecynyl group, and the like. Examples of the cycloalkenyl group include cyclic hydrocarbon groups having a carbon-carbon double bond and all other carbon-carbon bonds consisting of single bonds. Examples of the number of carbon atoms include 3 to 8. The number of carbon-carbon double bonds in the cycloalkenyl group is not limited, and examples thereof include 1 to 2, preferably 1. More specifically, examples of the cycloalkyl group include cyclopropenyl group, cyclobutenyl group, cyclopentenyl group, cyclohexenyl group, cyclohexadienyl group, cycloheptenyl group, cyclooctenyl group, and the like. The aryl group means a monovalent group formed by the elimination of one hydrogen atom from a monocyclic or polycyclic aromatic hydrocarbon compound, and examples thereof include those having 6 to 18 carbon atoms. In the present invention, the monocyclic or polycyclic aromatic hydrocarbon compound may be any hydrocarbon containing an aromatic ring, and one or more (for example, 1 to 3, 1 to 2, 1, etc.) acyclic hydrocarbons (for example, linear or branched alkyl groups, alkenyl groups, alkynyl groups, etc. (preferably linear or branched alkyl groups, etc.)) may be substituted on the cyclic structure-forming group. Similarly, in the present invention, the aryl group includes not only a group consisting of a cyclic structure but also a group formed by substituting one or more acyclic hydrocarbons on the cyclic structure-forming group. Examples of the aryl group include phenyl group, naphthyl group, anthracenyl group, diphenyl group, methylphenyl group, dimethylphenyl group, dodecylphenyl group, and the like. Examples of the arylalkyl group include the aforementioned alkyl groups having one or more (typically one) of the above aryl groups. Examples of the heteroaryl group include groups having a 5- to 14-membered saturated or unsaturated cyclic structure having at least one (e.g., 1 to 3, 1 to 2, 1) selected from the group consisting of an oxygen atom, a nitrogen atom, and a sulfur atom. For example, a tetrahydrofuryl group, a dihydrobenzofuranyl group, a pyridinyl group, a pyrimidinyl group, a thiophenyl group, an oxathiolanyl group, a quinolinyl group, a benzoquinolinyl group, etc. can be mentioned. The heteroaryl group may be a monocyclic group or a bicyclic group. The alkyl group having a cyclic structure refers to a hydrocarbon group having a cyclic structure in at least a part of its structure. Those having no carbon-carbon double bond are preferred. The alkyl group having a cyclic structure may be a group consisting of a hydrocarbon of the cyclic structure (e.g., a cycloalkyl group, a bicycloalkyl group, etc.), or a group in which a hydrocarbon group (e.g., an alkyl group (preferably an alkyl group having 1 to 3 carbon atoms), etc.) is substituted (e.g., 1 to 5, preferably 1 to 4) on the group consisting of the hydrocarbon of the cyclic structure. The number of carbon atoms of the alkyl group having a cyclic structure is not limited, but for example, 6 to 23, preferably 6 to 11, etc. can be mentioned. Examples of the bicycloalkyl group include monovalent groups formed by eliminating one hydrogen from a condensed ring having 5 to 8 carbon atoms, such as a bicyclo[1.1.1]pentanyl group, a bicyclo[2.1.1]hexanyl group, a bicyclo[2.2.1]heptanyl group, a bicyclo[2.2.2]octanyl group, etc.

[0035] <Alkoxysilane (a1) having a primary amino group> In the present invention, the alkoxysilane (a1) having a primary amino group is a compound represented by the following formula (1).

[0036] [Chemical formula]

[0037] In formula (1), R1 and R 2 is the same as or different from, and is a linear or branched alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, alkynyl group, cycloalkynyl group, aryl group or heteroaryl group having 1 to 18 carbon atoms, which may be substituted, and R 3 is a linear or branched alkylene group having 1 to 8 carbon atoms, preferably 1 to 5 carbon atoms, and n is an integer of 0 to 2.

[0038] Specific examples of the compound (a1) include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyl-methyldiethoxysilane, 3-aminopyropyl-methyldimethoxysilane, 4-amino-3,3-dimethylbutyltrimethoxysilane, 4-amino-3,3-dimethylbutyltriethoxysilane, and combinations thereof. 3-aminopropyltrimethoxysilane and 3-aminopropyltriethoxysilane are particularly preferred.

[0039] <Unsaturated carboxylic acid alkyl ester (a2)> In the present invention, the unsaturated carboxylic acid alkyl ester (a2) is a branched alkyl ester (a2-1) of an unsaturated dicarboxylic acid, and at least one selected from the group consisting of a branched alkyl ester of an unsaturated monocarboxylic acid which may contain a heteroatom or an alkyl ester having a cyclic structure (a2-2).

[0040] <Branched alkyl ester (a2-1) of unsaturated dicarboxylic acid> The branched alkyl ester (a2-1) of the unsaturated dicarboxylic acid is a branched alkyl esterified product of fumaric acid or maleic acid, and examples thereof include compounds represented by the following formula (2).

[0041] R 4 O-C(=O)-HC=CH-C(=O)-OR 5 (2)

[0042] In formula (2), R4 and R 5 are the same or different and are branched alkyl groups having 1 to 8 carbon atoms.

[0043] As used herein, the term "branched alkyl group" refers to an alkyl group in which the carbon skeleton constituting the alkyl group is branched. Examples of the branched alkyl group include an i-propyl group, a 1-methylpropyl group, an i-butyl group, a t-butyl group, an i-pentyl group, a t-pentyl group, and a 2-ethylhexyl group.

[0044] <Branched alkyl ester or alkyl ester having a cyclic structure which may contain a hetero atom of an unsaturated monocarboxylic acid (a2-2)> In the present invention, the branched alkyl ester or alkyl ester having a cyclic structure which may contain a hetero atom of the unsaturated monocarboxylic acid (a2-2) is specifically a compound represented by the following formula (3). H2C=CH-C(=O)-OR 6 (3)

[0045] In formula (3), R 6 represents a branched alkyl group having 3 to 18 carbon atoms or an alkyl group having a cyclic structure, or a group obtained by incorporating a hetero atom such as an oxygen atom, a nitrogen atom, or a sulfur atom into a branched or cyclic alkyl group having 1 to 18 carbon atoms.

[0046] Examples of the branched alkyl group include an i-propyl group, a 1-methylpropyl group, an i-butyl group, a t-butyl group, an i-pentyl group, a t-pentyl group, a 2-ethylhexyl group, an i-nonyl group, an i-decyl group, an i-tridecyl group, and an i-stearyl group. Examples of the alkyl group having a cyclic structure include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a phenyl group, a benzyl group, a trimethylcyclohexyl group, an isobornyl group, a dicyclopentanyl group, and an adamantyl group. A group formed by including a heteroatom, such as an oxygen atom, a nitrogen atom, or a sulfur atom, in an alkyl group or an arylalkyl group means a group in which some of the carbon atoms (typically carbon atoms other than the terminal part) (in the case of an arylalkyl group, typically the carbon atoms of the alkyl group part) contained in the alkyl group or the arylalkyl group are substituted with a heteroatom or a group consisting of a heteroatom and hydrogen (for example, -O-, -N=, -NH-, -S-, etc.). For example, a dimethylaminoethyl group corresponds to a group in which the carbon atom at the 3-position of an isopentyl group is substituted with -N=. Substitution of the above carbon atoms with a heteroatom (for example, an oxygen atom, a nitrogen atom, a sulfur atom, etc.) or a group consisting of a heteroatom and hydrogen may be present at one or a plurality of positions (for example, 1 to 3 positions, 1 to 2 positions, 1 position). The number of carbon atoms in the "group formed by including a heteroatom in an alkyl group or an arylalkyl group" indicates the number of carbon atoms in a structure in which some of the carbon atoms contained in the alkyl group or the arylalkyl group are substituted with a heteroatom or a group consisting of a heteroatom and hydrogen (for example, in the case of a dimethylaminoethyl group, the number of carbon atoms is 4). Examples of the group formed by including a heteroatom in an alkyl group include a tetrahydrofurfuryl group, a phenoxyethyl group, a dimethylaminoethyl group, and the like.

[0047] <Alkyl ester of saturated carboxylic acid (a3)> In the present invention, examples of the saturated carboxylic acid alkyl ester (a3) include a compound represented by the following formula (4). R 7 -C(=O)-OR 8 (4)

[0048] In formula (4), R 7 and R 8 are the same or different and each represents an alkyl group having 1 to 18 carbon atoms or a group formed by including a heteroatom, such as an oxygen atom, a nitrogen atom, or a sulfur atom, in an alkyl group having 1 to 18 carbon atoms. The alkyl group or the group formed by including a heteroatom, such as an oxygen atom, a nitrogen atom, or a sulfur atom, in the alkyl group represented by R 7 and R 8 does not have an unsaturated group.

[0049] Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, a 1-methylpropyl group, an n-butyl group, an i-butyl group, a t-butyl group, an n-pentyl group, an i-pentyl group, a t-pentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, a 2-ethylhexyl group, an n-nonyl group, an i-nonyl group, an n-decyl group, an i-decyl group, an n-undecyl group, an n-dodecyl group, an i-tridecyl group, an i-stearyl group, a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a trimethylcyclohexyl group, an isobornyl group, an adamantyl group, a 2,2,4-trimethylpentyl group, and the like. Examples of the group formed by including a hetero atom in the molecule of the alkyl group or the arylalkyl group include a tetrahydrofurfuryl group, a phenoxyethyl group, a dimethylaminoethyl group, and the like.

[0050] Specific examples of the saturated carboxylic acid alkyl ester (a3) include methyl acetate, ethyl acetate, n-propyl acetate, i-propyl acetate, n-butyl acetate, i-butyl acetate, n-pentyl acetate, i-pentyl acetate, cyclohexyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, 1-methylpentyl acetate (alias: sec-hexyl acetate), 2-methoxyethyl acetate, 2-ethoxyethyl acetate, 3-methoxybutyl acetate, 3-ethoxybutyl acetate, methyl propionate, ethyl propionate, n-propyl propionate, i-propyl propionate, n-butyl propionate, i-butyl propionate, n-pentyl propionate, i-pentyl propionate, methyl butyrate, ethyl butyrate, n-propyl butyrate, i-propyl butyrate, n-butyl butyrate, i-butyl butyrate, t-butyl butyrate, methyl valerate, ethyl valerate, methyl octanoate, methyl laurate, methoxypropyl acetate, ethyl 3-ethoxypropionate, butyl glycol acetate, butyl diglycol acetate, methyl i-valerate, ethyl i-valerate, methyl 3,3,5-trimethylhexanoate, methyl i-butyrate, ethyl i-butyrate, i-butyl i-butyrate, i-butyl n-butyrate, i-butyl t-butyrate, methyl 2-ethylhexanoate, methyl pivalate, ethyl 2-hydroxy-2-methylpropionate, methyl neodecanoate, and combinations thereof.

[0051] The saturated carboxylic acid alkyl ester (a3) is preferably an alkyl ester of a carboxylic acid having a linear structure with two or more hydrogen atoms at the α-position or a branched structure with two hydrogen atoms at the α-position. The alkyl ester of a carboxylic acid having such a structure has less influence of steric hindrance at the α-position compared to an alkyl ester having a branched structure with only one hydrogen atom at the α-position, and the reaction with the alkoxysilane (a1) can proceed at an appropriate rate, which is preferable.

[0052] Specific examples of the alkyl ester of a carboxylic acid having a straight-chain structure and having two or more hydrogen atoms at the α-position include, for example, methyl acetate, ethyl acetate, n-propyl acetate, i-propyl acetate, n-butyl acetate, i-butyl acetate, n-pentyl acetate, i-pentyl acetate, cyclohexyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, 1-methylpentyl acetate (alias: sec-hexyl acetate), 2-methoxyethyl acetate, 2-ethoxyethyl acetate, 3-methoxybutyl acetate, 3-ethoxybutyl acetate, methyl propionate, ethyl propionate, n-propyl propionate, i-propyl propionate, n-butyl propionate, i-butyl propionate, n-pentyl propionate, i-pentyl propionate, methyl butyrate, ethyl butyrate, n-propyl butyrate, i-propyl butyrate, n-butyl butyrate, i-butyl butyrate, t-butyl butyrate, methyl valerate, ethyl valerate, methyl octanoate, methyl laurate, methoxypropyl acetate, ethyl 3-ethoxypropionate, butyl glycol acetate, butyl diglycol acetate, and combinations thereof.

[0053] Specific examples of the alkyl ester of a carboxylic acid having a branched structure and having two hydrogen atoms at the α-position include methyl i-valerate, ethyl i-valerate, methyl 3,3,5-trimethylhexanoate, and combinations thereof.

[0054] <Polyisocyanate (a4)> In the present invention, the polyisocyanate (a4) is a compound having at least two isocyanate groups in one molecule. Examples of the polyisocyanate (a4) include aliphatic polyisocyanates, alicyclic polyisocyanates, araliphatic polyisocyanates, aromatic polyisocyanates, and their derivatives, etc., and combinations thereof.

[0055] Examples of the aliphatic polyisocyanate include aliphatic diisocyanates such as trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, pentamethylene diisocyanate, 1,2-propylene diisocyanate, 1,2-butylene diisocyanate, 2,3-butylene diisocyanate, 1,3-butylene diisocyanate, 2,4,4- or 2,2,4-trimethylhexamethylene diisocyanate, dimer acid diisocyanate, methyl 2,6-diisocyanatohexanoate (common name: lysine diisocyanate); and aliphatic triisocyanates such as 2-isocyanatoethyl 2,6-diisocyanatohexanoate, 1,6-diisocyanato-3-isocyanatomethylhexane, 1,4,8-triisocyanatooctane, 1,6,11-triisocyanatoundecane, 1,8-diisocyanato-4-isocyanatomethyloctane, 1,3,6-triisocyanatohexane, 2,5,7-trimethyl-1,8-diisocyanato-5-isocyanatomethyloctane, etc.

[0056] Examples of the alicyclic polyisocyanate include alicyclic diisocyanates such as 1,3 - cyclopentene diisocyanate, 1,4 - cyclohexane diisocyanate, 1,3 - cyclohexane diisocyanate, 3 - isocyanatomethyl - 3,5,5 - trimethylcyclohexyl isocyanate (common name: isophorone diisocyanate), 4 - methyl - 1,3 - cyclohexylene diisocyanate (common name: hydrogenated TDI), 2 - methyl - 1,3 - cyclohexylene diisocyanate, 1,3 - or 1,4 - bis(isocyanatomethyl)cyclohexane (common name: hydrogenated xylylene diisocyanate) or a mixture thereof, methylene bis(4,1 - cyclohexane diyl) diisocyanate (common name: hydrogenated MDI), norbornane diisocyanate; and alicyclic triisocyanates such as 1,3,5 - triisocyanatocyclohexane, 1,3,5 - trimethylisocyanatocyclohexane, 2 - (3 - isocyanatopropyl)-2,5 - bis(isocyanatomethyl)-bicyclo(2.2.1)heptane, 2 - (3 - isocyanatopropyl)-2,6 - bis(isocyanatomethyl)-bicyclo(2.2.1)heptane, 3 - (3 - isocyanatopropyl)-2,5 - bis(isocyanatomethyl)-bicyclo(2.2.1)heptane, 5 - (2 - isocyanatoethyl)-2 - isocyanatomethyl - 3 - (3 - isocyanatopropyl)-bicyclo(2.2.1)heptane, 6 - (2 - isocyanatoethyl)-2 - isocyanatomethyl - 3 - (3 - isocyanatopropyl)-bicyclo(2.2.1)heptane, 5 - (2 - isocyanatoethyl)-2 - isocyanatomethyl - 2 - (3 - isocyanatopropyl)-bicyclo(2.2.1)-heptane, 6 - (2 - isocyanatoethyl)-2 - isocyanatomethyl - 2 - (3 - isocyanatopropyl)-bicyclo(2.2.1)heptane, etc.

[0057] Examples of the aromatic aliphatic polyisocyanate include aromatic aliphatic diisocyanates such as methylene bis(4,1-phenylene) diisocyanate (common name: MDI), 1,3- or 1,4-xylylene diisocyanate or a mixture thereof, ω,ω'-diisocyanato-1,4-diethylbenzene, 1,3- or 1,4-bis(1-isocyanato-1-methylethyl)benzene (common name: tetramethylxylylene diisocyanate) or a mixture thereof; and aromatic aliphatic triisocyanates such as 1,3,5-triisocyanatomethylbenzene.

[0058] Examples of the aromatic polyisocyanate include aromatic diisocyanates such as m-phenylene diisocyanate, p-phenylene diisocyanate, 4,4'-diphenyl diisocyanate, 1,5-naphthalene diisocyanate, 2,4-tolylene diisocyanate (common name: 2,4-TDI) or 2,6-tolylene diisocyanate (common name: 2,6-TDI) or a mixture thereof, 4,4'-toluidine diisocyanate, 4,4'-diphenyl ether diisocyanate; aromatic triisocyanates such as triphenylmethane-4,4',4''-triisocyanate, 1,3,5-triisocyanatobenzene, 2,4,6-triisocyanatotoluene; and aromatic tetraisocyanates such as 4,4'-diphenylmethane-2,2',5,5'-tetraisocyanate.

[0059] Examples of the derivative of the polyisocyanate include dimers, trimers, biurets, allophanates, uretdiones, uretoimines, isocyanurates, oxadiazinetriones, etc. of the above polyisocyanates, and polymethylene polyphenyl polyisocyanate (crude MDI, polymeric MDI), crude TDI, etc. The polyisocyanate derivative may be modified with a polyol compound and / or a monoalcohol compound containing a known diol or triol in order to adjust the functional group number of the isocyanate group or to adjust the compatibility and physical properties.

[0060] As the above polyisocyanate (a4), a polyisocyanate derivative having an isocyanate group content of 10% by mass or more, 12% by mass or more, 30% by mass or less, and 25% by mass or less is preferable.

[0061] Here, the isocyanate group content of the polyisocyanate (a4) represents the amount of isocyanate groups in the polyisocyanate (a4) as a mass fraction. The isocyanate group content can be a catalog value or measured according to the method for determining the isocyanate group content in JIS K1603-1.

[0062] <Modified Polyisocyanate and Its Manufacturing Method> In the present invention, as a first aspect, the modified polyisocyanate is a reaction product (referred to as modified polyisocyanate (X)) using components containing an alkoxysilane (a1) having a primary amino group, an unsaturated carboxylic acid alkyl ester (a2), and a polyisocyanate (a4) as raw materials. Preferably, the primary amino group of the alkoxysilane (a1) adds to the unsaturated carbon-carbon bond of the unsaturated carboxylic acid alkyl ester (a2), and the secondary amino group of the alkoxysilane N-position modified product represented by formula (5) or (6) adducts to the isocyanate group of the polyisocyanate (a4):

[0063]

Chemical formula

[0064] In formula (5), R 1 and R 2 are the same or different and are a linear or branched alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, alkynyl group, cycloalkynyl group, aryl group, or heteroaryl group having 1 to 18 carbon atoms, which may be substituted. R 3 is a linear or branched alkylene group having 1 to 8 carbon atoms, preferably 1 to 5 carbon atoms. R 4 and R 5 are the same or different and are branched alkyl groups having 1 to 8 carbon atoms, and n is an integer of 0 to 2.

[0065] [Chemical formula]

[0066] In formula (6), R 1 and R 2 are the same or different and are a linear or branched alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, alkynyl group, cycloalkynyl group, aryl group or heteroaryl group having 1 to 18 carbon atoms which may be substituted, R 3 is a linear or branched alkylene group having 1 to 8 carbon atoms, preferably 1 to 5 carbon atoms, and R 6 is an alkyl group having a branched or cyclic structure with 1 to 18 carbon atoms, or a group formed by including a heteroatom in a molecule of an alkyl group or arylalkyl group having a branched or cyclic structure with 1 to 18 carbon atoms, and n is an integer of 0 to 2.

[0067] Alternatively, as a second aspect, it is a reaction product (denoted as modified polyisocyanate (Y)) using a component containing an alkoxysilane (a1) having a primary amino group, a saturated carboxylic acid alkyl ester (a3) and a polyisocyanate (a4) as raw materials. Preferably, the alkoxysilane N-position modified product obtained by reacting the alkoxysilane (a1) with the saturated carboxylic acid alkyl ester (a3) is an N-position acyl modified product represented by the following formula (7) having a secondary amide group, and the secondary amide group is adducted to the isocyanate group of the polyisocyanate (a4); it is a modified polyisocyanate.

[0068] [Chemical formula]

[0069] In formula (7), R 1 and R 2is the same or different and is a linear or branched alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, alkynyl group, cycloalkynyl group, aryl group or heteroaryl group having 1 to 18 carbon atoms which may be substituted, n is an integer of 0 to 2, R 3 is a linear or branched alkylene group having 1 to 8 carbon atoms, preferably 1 to 5 carbon atoms, R 7 is an alkyl group having 1 to 18 carbon atoms and having no unsaturated group, or a group formed by including a heteroatom in the molecule of an alkyl group having 1 to 18 carbon atoms and having no unsaturated group.

[0070] As a method for producing the modified polyisocyanate (X) or (Y), a method may be used in which an alkoxysilane (a1) having a primary amino group, an unsaturated carboxylic acid alkyl ester (a2) or a saturated carboxylic acid alkyl ester (a3) and a polyisocyanate (a4) are simultaneously reacted. Preferably, a production method is used in which the alkoxysilane (a1) and the unsaturated carboxylic acid alkyl ester (a2) or the saturated carboxylic acid alkyl ester (a3) are reacted in advance to obtain an alkoxysilane N-position modified product having a secondary amino group or a secondary amide group, and this is further reacted with the polyisocyanate (a4).

[0071] Production method of modified polyisocyanate (X): In the modified polyisocyanate (X), the blending ratio of the alkoxysilane (a1) having a primary amino group and the unsaturated carboxylic acid alkyl ester (a2) is preferably in the range of, for example, 0.7 mol or more, 0.85 mol or more, 1.5 mol or less, and 1.25 mol or less of the unsaturated carboxylic acid alkyl ester (a2) per 1 mol of the alkoxysilane (a1) having a primary amino group.

[0072] Further, when the unsaturated carboxylic acid alkyl ester (a2) in the modified polyisocyanate (X) is a branched alkyl ester (a2-1) of an unsaturated dicarboxylic acid, the reaction ratio of the alkoxysilane N-position modified product having the secondary amino group to the polyisocyanate (a4) is preferably adjusted so that the secondary amino group is 40 mol or less, preferably 3 mol or more and 35 mol or less per 100 mol of isocyanate groups, from the viewpoints of the adhesion to iron and non-ferrous metals of the coating, curability, and storage stability of the modified polyisocyanate.

[0073] In the modified polyisocyanate (X), when the unsaturated carboxylic acid alkyl ester (a2) is a branched alkyl ester (a2-2) of an unsaturated monocarboxylic acid which may contain a hetero atom or an alkyl ester having a cyclic structure, in addition to the alkoxysilane N-position modified product represented by the formula (6), a compound represented by the following formula (8) is by-produced by the reaction of the alkoxysilane (a1) having a primary amino group with the unsaturated carboxylic acid alkyl ester (a2), and in some cases, a mixture containing an alkoxysilane N-position modified product in which the unreacted alkoxysilane (a1) having a primary amino group is mixed is obtained.

[0074]

Chemical formula

[0075] In the formula (8), R 1 and R 2 are the same or different and are a linear or branched alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, alkynyl group, cycloalkynyl group, aryl group or heteroaryl group having 1 to 18 carbon atoms which may be substituted, R 3 is a linear or branched alkylene group having 1 to 8 carbon atoms, preferably 1 to 5 carbon atoms, R 6 is an alkyl group having a branched or cyclic structure having 1 to 18 carbon atoms, or a group formed by including a hetero atom in a molecule of an alkyl group or arylalkyl group having a branched or cyclic structure having 1 to 18 carbon atoms, and n is an integer of 0 to 2.

[0076] Therefore, in this case, the reaction between the alkoxysilane N-position modified product having the secondary amino group and the polyisocyanate (a4) is carried out in the coexistence of the alkoxysilane (a1) having an unreacted primary amino group and the tertiary amino group-containing compound represented by the formula (8) which is a by-product.

[0077] In the modified polyisocyanate (X), when the unsaturated carboxylic acid alkyl ester (a2) is a branched alkyl ester which may contain a hetero atom of the unsaturated monocarboxylic acid or an alkyl ester having a cyclic structure (a2-2), as the reaction ratio between the mixture containing the alkoxysilane N-position modified product and the polyisocyanate (a4), from the viewpoints of the adhesion to the iron and non-ferrous metals of the coating, the curability and the storage stability of the modified polyisocyanate (X), it is preferably adjusted so that the total number of moles of the primary amino group and the secondary amino group is 40 moles or less, preferably 3 moles or more and 35 moles or less, per 100 moles of the isocyanate group.

[0078] The reaction for obtaining the alkoxysilane N-position modified product from the alkoxysilane (a1) having a primary amino group and the unsaturated carboxylic acid alkyl ester (a2) can be carried out at 0 to 110 ° C while blowing air as necessary. The reaction time varies depending on the temperature, but is 1 hour to 2 weeks. When reacting, it may be mixed by a method of adding the unsaturated carboxylic acid alkyl ester (a2) to the alkoxysilane (a1) having a primary amino group, or may be mixed by a method of adding the alkoxysilane (a1) having a primary amino group to the unsaturated carboxylic acid alkyl ester (a2). In order to prevent the polymerization of the unsaturated carboxylic acid alkyl ester (a2), a small amount of a known aromatic polymerization inhibitor such as methoquinone or a nitroso compound such as N-oxyl may coexist as necessary.

[0079] The reaction between the alkoxysilane N-position modified product obtained from an alkoxysilane (a1) having a primary amino group and an unsaturated carboxylic acid alkyl ester (a2) and the above polyisocyanate (a4) can be carried out under known and commonly used reaction conditions without particular limitation. Specifically, examples of the method include stirring and mixing the alkyl alkoxysilane N-position modified product and the polyisocyanate (a4) at 0 to 80°C for 0.1 to 5 hours, either all at once or dropwise. In this case, depending on the required performance, the mixing may be carried out by adding the alkoxysilane N-position modified product to the polyisocyanate (a4), or by adding the polyisocyanate (a4) to the alkoxysilane N-position modified product. In this reaction, a Lewis acid catalyst, a basic catalyst, and an organic solvent can also be used as required. The mixture containing the obtained reaction product may be aged at 0 to 80°C for 1 day to 1 month as required.

[0080] Method for producing modified polyisocyanate (Y): In the reaction for obtaining an alkoxysilane N-position modified product from an alkoxysilane (a1) having a primary amino group and a saturated carboxylic acid alkyl ester (a3), the blending ratio of the alkoxysilane (a1) having a primary amino group to the saturated carboxylic acid alkyl ester (a3) is preferably in the range of, for example, 0.7 mol or more and 1.5 mol or less, 0.85 mol or more and 1.25 mol or less of the saturated carboxylic acid alkyl ester (a3) per 1 mol of the alkoxysilane (a1) having a primary amino group.

[0081] The reaction between an alkoxysilane (a1) having a primary amino group and an alkyl saturated carboxylate (a3) may be carried out by heating at 100 to 250°C, or may be carried out at 0 to 160°C by adding a basic catalyst or a Lewis acid catalyst. When adding a catalyst, it is more preferable to add a small amount of a basic catalyst because it is easier to exhibit an effect. Any of these conditions may be reacted under pressure as required. In this reaction, in order to suppress coloring and the like, the reaction may be carried out in the coexistence of a known antioxidant such as methoquinone. The reaction time varies depending on conditions such as temperature, but is usually about 1 hour to 3 days. And it is preferable to mix all at once or by dropwise addition, and further combine aging as required.

[0082] When adding a basic catalyst or a Lewis acid catalyst, it may be added after mixing the alkoxysilane (a1) having a primary amino group and the alkyl saturated carboxylate (a3), or may be added to the alkoxysilane (a1) having a primary amino group in advance and then mixed with the alkyl saturated carboxylate (a3), or may be added to the alkyl saturated carboxylate (a3) in advance and then mixed with the alkoxysilane (a1) having a primary amino group.

[0083] In the present invention, the modified polyisocyanate (Y) is In the presence of a basic catalyst, step (1) of reacting an alkoxysilane (a1) having a primary amino group and an alkyl saturated carboxylate (a3), Step (2) of adding an acidic compound as required to the mixture containing the reaction product obtained in the above step (1), removing part or all of the alcohol generated as a by-product, and preparing an intermediate containing an N-acyl modified product represented by the following formula (7), Step (4) of reacting the intermediate with a polyisocyanate (a4) is preferably produced by.

[0084]

Chemical formula

[0085] In formula (7), R 1 and R 2 are the same or different and are a linear or branched alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, alkynyl group, cycloalkynyl group, aryl group or heteroaryl group having 1 to 18 carbon atoms which may be substituted, and R 3 is a linear or branched alkylene group having 1 to 8 carbon atoms, preferably 1 to 5 carbon atoms, n is an integer of 0 to 2, and R 7 represents an alkyl group having 1 to 18 carbon atoms and no unsaturated group, or a group having 1 to 18 carbon atoms and containing a hetero atom such as an oxygen atom, a nitrogen atom or a sulfur atom in the molecule of the alkyl group and having no unsaturated group.

[0086] By such a production method, a modified polyisocyanate excellent in adhesion to non-ferrous metals can be easily obtained.

[0087] Examples of the basic catalyst added in step (1) include metal hydroxides such as lithium hydroxide, sodium hydroxide, potassium hydroxide, calcium hydroxide; carbonates such as sodium carbonate, potassium carbonate; hydrogen carbonates such as sodium hydrogen carbonate, potassium hydrogen carbonate; metal alkoxides such as sodium methoxide, potassium t-butoxide; organometals such as butyllithium; potassium silanolate; nitrogen compounds such as ammonia gas, aqueous ammonia, methylamine, trimethylamine, triethylamine, 1,8-diazabicyclo[5.4.0]-7-undecene (DBU), 1,5-diazabicyclo[4.3.0]-5-nonene (DBN). These basic catalysts may be used without being dissolved in an organic solvent, or may be dissolved in a solvent such as water; alcohols such as methanol and ethanol; esters such as methyl acetate and ethyl acetate; ethers such as tetrahydrofuran, cyclopentyl methyl ether, trimethyl orthoacetate and added.

[0088] Examples of the acidic compound added in step (2) include inorganic Bronsted acids such as hydrogen chloride, hydrochloric acid, sulfuric acid, nitric acid, and phosphoric acid; organic Bronsted acids such as carboxylic acids, alkylsulfonic acids, arylsulfonic acids, monoalkyl phosphoric acids, dialkyl phosphoric acids, and arylphosphonic acids; and acyl chlorides such as acetyl chloride and benzoyl chloride. These acidic compounds may be used without being dissolved in an organic solvent, or alternatively, they may be dissolved in a solvent such as water; alcohols such as methanol and ethanol; esters such as methyl acetate and ethyl acetate; and ethers such as tetrahydrofuran, cyclopentyl methyl ether, and trimethyl orthoacetate in advance and then added. It is desirable that the addition of the acidic compound be carried out before step (3), but it may also be carried out during step (3).

[0089] In step (3), while heating and optionally reducing the pressure, a part or all of the alcohol by-produced in step (1) and, if necessary, the alkoxysilane (a1) having a primary amino group remaining as an unreacted raw material and / or the saturated carboxylic acid alkyl ester (a3) are removed. In the present invention, the removal may be carried out using either of two methods: concentration and distillation. Concentration is a method of removing the compound to be removed outside the system and leaving the required compound inside the system, whereas distillation is a method of taking out the required compound outside the system. In distillation, the N-position acyl-modified product can be obtained as a highly pure purified N-position acyl-modified product, but the process and the required equipment are complex, and furthermore, the required energy is large and the environmental load is large. On the other hand, in concentration, not only impurities such as catalyst residues are included, but in some cases, the alkoxysilane (a1) having an unreacted primary amino group and the saturated carboxylic acid alkyl ester (a3) are also included, so that the N-position acyl-modified product is obtained as a crude N-position acyl-modified product with low purity. However, the process and the required equipment are simple, and furthermore, the required energy is small and the environmental load is small. From the viewpoint of easy manufacturability, it is more advantageous to carry out the removal using the concentration method.

[0090] In the present invention, even if step (3) is carried out by concentration instead of distillation, it is possible to provide a modified polyisocyanate as a paint curing agent with sufficient performance by reaction with polyisocyanate (a4). On the other hand, in order to further enhance the anticorrosion property or corrosion resistance of the coating film, the above-mentioned crude N-position acyl-modified product obtained by using a carboxylic acid ester having a branched structure and having two hydrogen atoms at the α-position as the saturated carboxylic acid alkyl ester (a3) may be purified by distillation and used as necessary. On the other hand, the above-mentioned crude N-position acyl-modified product obtained by using a carboxylic acid ester having a linear structure and having two or more hydrogen atoms at the α-position as the saturated carboxylic acid alkyl ester (a3) is more preferable from the viewpoint of easy manufacturability because it is easy to obtain a coating film showing extremely high anticorrosion property and weather resistance even when used without distillation and purification.

[0091] Step (4) may be carried out at 40 to 200 °C without adding a catalyst, or may be carried out at 20 to 140 °C by adding a basic catalyst or a Lewis acid catalyst. When a catalyst is added in step (4), a Lewis acid catalyst is more preferable because a small amount thereof easily exhibits an effective action. As the Lewis acid catalyst, known ones can be used, such as tin compounds such as dialkyltin dicarboxylate, monoalkyltin tricarboxylate, dialkyltin oxide, and tin dicarboxylate; zinc compounds such as zinc dicarboxylate and zinc bis(acetylacetonate); zirconium compounds such as zirconium tetraalkoxide, dialkoxyzirconium bis(acetylacetonate), and zirconium tetra(acetylacetonate); titanium compounds such as titanium tetraalkoxide, dialkoxytitanium bis(acetylacetonate), and titanium tetra(acetylacetonate); aluminum compounds such as aluminum tris(acetylacetonate); and bismuth compounds such as bismuth tricarboxylate.

[0092] Step (1), step (2), step (3) and step (4) may each be subjected to a filtration operation as necessary, and a known filter medium can be used for the filtration operation.

[0093] In the production of the modified polyisocyanate (Y), as the reaction ratio of the purified alkoxysilane N-position modified product or the crude alkoxysilane N-position modified product obtained from the alkoxysilane (a1) having a primary amino group and the saturated carboxylic acid alkyl ester (a3) and the polyisocyanate (a4), it is preferably adjusted so that the total number of moles of the secondary amide group and the primary amino group is 40 moles or less, preferably 3 moles or more and 35 moles or less, per 100 moles of the isocyanate group.

[0094] As described above, the modified polyisocyanate of the present invention is preferably produced via an alkoxysilane N-position modified product having the secondary amino group or the secondary amide group such as the modified polyisocyanate (X) or the modified polyisocyanate (Y), which is effective in improving the compatibility with the active hydrogen group-containing compound and the organic solvent described below. In addition, in order to enhance the stability and the like of the modified polyisocyanate of the present invention, after reacting the alkoxysilane N-position modified product having the secondary amino group or the secondary amide group with the polyisocyanate, the above-mentioned acidic compound may be added later as necessary.

[0095] When obtaining the alkoxysilane N-position modified product, in order to adjust the performance of the coating film obtained using the modified polyisocyanate as a curing agent, an alkoxysilane having both a primary amino group and a secondary amino group such as 3-(2-aminoethylamino)propyltrialkoxysilane may be used in combination with the alkoxysilane (a1) having a primary amino group and reacted with the unsaturated carboxylic acid alkyl ester (a2) or the saturated carboxylic acid alkyl ester (a3).

[0096] The amount of isocyanate groups in the modified polyisocyanate of the present invention is preferably in the range of, for example, 1.0 mmol or more, 2.0 mmol or more per 1 g of the non-volatile content of the modified polyisocyanate from the viewpoints of the curability of the coating film, the adhesion to non-ferrous metals, the weather resistance, and the corrosion resistance. The upper limit of the amount of isocyanate groups in the modified polyisocyanate is not limited, but can be designed in the range of, for example, 5.5 mmol or less, 5.0 mmol or less per 1 g of the non-volatile content of the modified polyisocyanate.

[0097] The amount of isocyanate groups in the modified polyisocyanate can be determined, for example, by adding 10 ml of 0.1 mol / L dibutylamine solution to 0.1 g of the sample to react the NCO groups, and titrating the remaining dibutylamine with an aqueous hydrochloric acid solution using bromophenol blue as a titration indicator.

[0098] In this specification, the non-volatile content is the residue obtained by removing volatile components such as organic solvents, and can be measured according to the standard of JIS K 5601 1-2 (heating temperature: 125 °C, heating time: 60 minutes).

[0099] In the present invention, an organic solvent can be used as a reaction solvent for producing the modified polyisocyanate or as a diluting solvent for diluting the modified polyisocyanate to a viscosity suitable as a curing agent for paints. As the organic solvent, those generally used in the paint field can be used. Specific examples include aliphatic solvents such as n-butane, n-hexane, n-heptane, n-octane, cyclopentane, cyclohexane, and cyclobutane; aromatic solvents such as toluene and xylene; ketone solvents such as methyl i-butyl ketone; ether solvents such as n-butyl ether, dioxane, and cyclopentyl methyl ether; ester solvents such as ethyl acetate, n-propyl acetate, i-propyl acetate, n-butyl acetate, i-butyl acetate, ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether acetate, and butyl carbitol acetate; ketone solvents such as methyl ethyl ketone, methyl i-butyl ketone, and di-i-butyl ketone; combinations thereof, and the like. Also, gasoline, kerosene, coal tar naphtha (including solvent naphtha), petroleum ether, petroleum naphtha, petroleum benzine, turpentine oil, mineral spirits (including mineral thinner, petroleum spirit, white spirit, and mineral terpene), and other organic solvents with weak dissolving power, which are customarily called weak solvents in the paint field, can also be sufficiently used.

[0100] In the present invention, the organic solvent can be contained in either the main agent or the curing agent. As for the amount of the organic solvent contained in the curing agent, it is preferably in the range of 200 parts by mass or less, more preferably 10 parts by mass or more and 100 parts by mass or less, based on 100 parts by mass of the non-volatile content of the modified polyisocyanate. In a typical embodiment, the modified polyisocyanate of the present invention is used as a curing agent for coating. Therefore, in one embodiment, the present invention provides a curing agent containing the modified polyisocyanate. In such an embodiment, the curing agent of the present invention is preferably used together with an active hydrogen-containing compound. Further, in the present invention, either only the modified polyisocyanate can be used as a curing agent, or a curing agent composition further containing the above solvent, catalyst, ultraviolet absorber, light stabilizer, viscosity modifier, surface modifier, dehydrating agent, etc. in addition to the modified polyisocyanate can also be used. These components other than the modified polyisocyanate can be used alone or in combination of two or more. In an embodiment of the curing agent composition, the content ratio of the modified polyisocyanate in the composition is not limited, but can be set, for example, in the range of 30% by mass or more, 40% by mass or more, 50% by mass or more, 60% by mass or more, 70% by mass or more, 80% by mass or more, 90% by mass or more, 95% by mass or more, 99% by mass or more, etc.

[0101] <Active hydrogen group-containing compound> In the present invention, the active hydrogen group-containing compound is a compound used as a binder component together with the modified polyisocyanate, and is not particularly limited as long as it has an active hydrogen group, and may be a commonly known one in the paint field. The active hydrogen group here is a group capable of reacting with the isocyanate group of the modified polyisocyanate, and examples thereof include a hydroxy group, a primary or secondary amino group, and a thiol group. Specific examples of the active hydrogen group-containing compound include, for example, acrylic polyol, polyester polyol, polyether polyol, polycarbonate polyol, epoxy polyol, dihydroxyalkane, trihydroxyalkane, polyol compounds of dihydroxycycloalkane; acrylic resin having a pendant amino group, polyallylamine, polyether polyamine, polylysine and polyvinylamine, a polymer having a plurality of secondary amino groups having an aspartic acid ester structure, polyamino compounds such as diaminoalkane, diaminocycloalkane, dialkylenetriamine, trialkylenetetraamine, bisaspartic acid ester derivative, and the like. These can be used alone or in combination.

[0102] Among them, as the active hydrogen group-containing compound, from the viewpoints of enhancing the weather resistance of the formed coating film, enhancing the compatibility in the paint, increasing the non-volatile content concentration of the paint, or controlling the reaction rate with the isocyanate group, etc., it is preferable to contain acrylic polyol and / or bisaspartic acid ester derivative. Further, in order to adjust the flexibility of the coating film, etc., polyester polyol or polyether polyol may be used in combination as necessary.

[0103] The acrylic polyol may be produced, for example, by copolymerizing a hydroxyl group-containing polymerizable unsaturated monomer and other polymerizable unsaturated monomers (polymerizable unsaturated monomers other than the hydroxyl group-containing polymerizable unsaturated monomer), or commercially available products etc. may also be used.

[0104] The above hydroxyl group-containing polymerizable unsaturated monomer is a compound having at least one hydroxyl group and at least one polymerizable unsaturated group in one molecule. Examples of the hydroxyl group-containing polymerizable unsaturated monomer include monoesterified products of (meth)acrylic acid and a divalent alcohol having 2 to 8 carbon atoms, such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate; ε-caprolactone-modified products of the monoesterified products of (meth)acrylic acid and a divalent alcohol having 2 to 8 carbon atoms; adducts of (meth)acrylic acid and an epoxy group-containing compound (for example, "Cardura E10P" (trade name, manufactured by Hexion, glycidyl neodecanoate)); N-hydroxymethyl (meth)acrylamide; allyl alcohol; and (meth)acrylates having a polyoxyethylene chain with a hydroxyl group at the molecular terminal, etc.

[0105] As other polymerizable unsaturated monomers copolymerizable with the above hydroxyl group-containing polymerizable unsaturated monomer, for example, monomers shown in the following (1) to (7) can be used. These polymerizable unsaturated monomers can be used alone or in combination of two or more.

[0106] (1) Acid group-containing polymerizable unsaturated monomer The acid group-containing polymerizable unsaturated monomer is a compound having at least one acid group and at least one polymerizable unsaturated group in one molecule. Examples of the monomer include carboxyl group-containing monomers such as (meth)acrylic acid, crotonic acid, itaconic acid, maleic acid, and maleic anhydride; sulfonic acid group-containing monomers such as vinylsulfonic acid, 2-sulfoethyl (meth)acrylate; and acidic phosphate ester-based monomers such as 2-(meth)acryloyloxyethyl acid phosphate, 2-(meth)acryloyloxypropyl acid phosphate, 2-(meth)acryloyloxy-3-chloropropyl acid phosphate, 2-methacryloyloxyethyl phenyl phosphate, etc. These can be used singly or in combination of two or more.

[0107] (2) Esterification product of acrylic acid or methacrylic acid and a monohydric alcohol having 1 to 20 carbon atoms Specific examples include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, n-butyl (meth)acrylate, i-butyl (meth)acrylate, t-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, i-octyl (meth)acrylate, i-myristyl (meth)acrylate, stearyl (meth)acrylate, "isostearyl acrylate" (manufactured by Osaka Organic Chemical Industry Co., Ltd., trade name), lauryl (meth)acrylate, tridecyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, cyclohexyl (meth)acrylate, isobornyl (meth)acrylate, and the like.

[0108] (3) Polymerizable unsaturated monomer containing an alkoxysilyl group The polymerizable unsaturated monomer containing an alkoxysilyl group is a compound having at least one alkoxysilyl group and at least one polymerizable unsaturated group in one molecule. Examples of the polymerizable unsaturated monomer containing an alkoxysilyl group include vinyltrimethoxysilane, vinyltriethoxysilane, acryloxyethyltrimethoxysilane, methacryloxyethyltrimethoxysilane, acryloxypropyltrimethoxysilane, methacryloxypropyltrimethoxysilane, acryloxypropyltriethoxysilane, methacryloxypropyltriethoxysilane, vinyltris(β-methoxyethoxy)silane, and the like.

[0109] (4) Aromatic vinyl monomer Specific examples include styrene, α-methylstyrene, vinyltoluene, and the like. When an aromatic vinyl monomer is used as a constituent component, its blending ratio is preferably in the range of 3% by mass or more, 5% by mass or more, 50% by mass or less, and 40% by mass or less based on the total amount of the monomer components.

[0110] (5) Polymerizable unsaturated monomer containing a glycidyl group The glycidyl group-containing polymerizable unsaturated monomer is a compound having at least one glycidyl group and at least one polymerizable unsaturated group in one molecule, and specific examples thereof include glycidyl acrylate, glycidyl methacrylate, and the like.

[0111] (6) Polymerizable unsaturated group-containing nitrogen atom-containing compound For example, (meth)acrylamide, N,N-dimethyl(meth)acrylamide, N-[3-(dimethylamino)propyl](meth)acrylamide, N-butoxymethyl(meth)acrylamide, diacetone(meth)acrylamide, N,N-dimethylaminoethyl (meth)acrylate, vinyl pyridine, vinyl imidazole, acrylonitrile, methacrylonitrile, and the like can be mentioned.

[0112] (7) Other vinyl compounds For example, vinyl acetate, vinyl propionate, vinyl chloride, versatic acid vinyl ester, and the like can be mentioned.

[0113] In the present invention, the polymerizable unsaturated monomer refers to a monomer having one or more (for example, 1 to 4) polymerizable unsaturated groups. The polymerizable unsaturated group means an unsaturated group capable of radical polymerization. Examples of such polymerizable unsaturated groups include a vinyl group, a (meth)acryloyl group, a (meth)acrylamide group, a vinyl ether group, an allyl group, a propenyl group, an i-propenyl group, a maleimide group, and the like.

[0114] In addition, in this specification, “(meth)acrylate” means acrylate or methacrylate. “(Meth)acrylic acid” means acrylic acid or methacrylic acid. Also, “(meth)acryloyl” means acryloyl or methacryloyl. Also, “(meth)acrylamide” means acrylamide or methacrylamide.

[0115] From the viewpoints of the weather resistance and corrosion resistance of the formed coating film, the acrylic polyol preferably has a hydroxyl value in the range of 5 mgKOH / g or more, 10 mgKOH / g or more, 160 mgKOH / g or less, and 100 mgKOH / g or less, and a weight average molecular weight in the range of 3000 or more, 10000 or more, 100000 or less, and 50000 or less.

[0116] In this specification, the weight average molecular weight is a value calculated based on the weight average molecular weight of standard polystyrene from the chromatogram measured by gel permeation chromatography. The gel permeation chromatography was performed using "HLC8120GPC" (manufactured by Tosoh Corporation). As the columns, four columns of "TSKgel G-4000HXL", "TSKgel G-3000HXL", "TSKgel G-2500HXL", and "TSKgel G-2000HXL" (all manufactured by Tosoh Corporation, trade names) were used. The mobile phase was tetrahydrofuran, the measurement temperature was 40 °C, the flow rate was 1 mL / min, and the detector was RI.

[0117] As the bis-aspartic acid ester derivative, any compound obtained by adding a maleic acid diester or a fumaric acid diester to an aspartic acid compound having two amino groups may be used. For example, tetraethyl N,N‘-(methylenedi-4,1-cyclohexanediyl)-bis-aspartate, tetraethyl N,N‘-(methylenebis(2-methyl-di-4,1-cyclohexanediyl))-bis-aspartate, tetraethyl N,N‘-(2-methyl-1,5-pentanediyl)-bis-aspartate, etc. More specifically, for example, Desmophen NH 1420, Desmophen NH 1520, Desmophen NH 1220, Desmophen NH 1422, Desmophen NH 1423LF, Desmophen NH 1720, Desmophen NH 1723LF, Desmophen NH 1523LF, Desmophen NH 1521, etc. manufactured by Covestro; Amicure IC-133, Amicure IC-166, Amicure IC-186 (the above are trade names), etc. manufactured by Evonik.

[0118] <Coating> The present invention provides a coating comprising an active hydrogen-containing compound and the modified polyisocyanate. The coating of the present invention also includes a two-component composition comprising a curing agent containing a separately stored modified polyisocyanate and a main agent containing the active hydrogen group-containing compound. In a typical embodiment, the coating of the present invention is obtained by mixing a curing agent containing a separately stored modified polyisocyanate and a main agent containing the active hydrogen group-containing compound before painting. The coating of the present invention can also be referred to as a paint composition. As for the usage ratio, when based on 1 equivalent of the active hydrogen group contained in the active hydrogen group-containing compound, a ratio such that the equivalent ratio of the modified polyisocyanate is 0.5 or more and 0.7 or more is preferable. When based on 1 equivalent of the active hydrogen group contained in the active hydrogen group-containing compound, the equivalent ratio of the modified polyisocyanate is not limited, but can be designed, for example, to be 2.5 or less, 1.5 or less, etc.

[0119] The coating of the present invention may further contain, as necessary, a rust inhibitor, a catalyst, a coloring pigment, a extender pigment, a pearlescent pigment, a dispersant, an ultraviolet absorber, a light stabilizer, an antifoaming agent, a viscosity modifier, a surface conditioner, a dehydrating agent, an organic solvent, a crosslinking agent, a binder component other than the active hydrogen group-containing compound, etc., as appropriate.

[0120] Among these, as the rust inhibitor, a rust inhibitor known in the paint field can be used and is commercially available. The rust inhibitor may be an inorganic compound or an organic compound, and there is no limitation on its form such as a single compound, a composite compound, a composition in which a plurality of these compounds are used in combination, a composition in which a plurality of these compounds are subjected to a firing treatment, etc. Specific examples include phosphate-based metal compounds such as zinc phosphate, magnesium phosphate, magnesium ammonium phosphate eutectic, monomagnesium hydrogen phosphate, dihydrogen magnesium phosphate, magnesium calcium phosphate eutectic, magnesium cobalt phosphate eutectic, magnesium nickel phosphate eutectic, calcium phosphate, calcium ammonium phosphate, calcium hydrogen phosphate, calcium dihydrogen phosphate, calcium chloride fluoride phosphate, aluminum phosphate, aluminum hydrogen phosphate; Phosphite-based metal compounds such as magnesium phosphite, calcium phosphite, magnesium calcium phosphite eutectic, basic zinc phosphite, barium phosphite, manganese phosphite, calcium hypophosphite; Metal silicate salts such as calcium silicate, zinc silicate, aluminum silicate, aluminum orthosilicate, hydrated aluminum silicate, aluminosilicate, borosilicate, beryllosilicate, calcium aluminum silicate, sodium aluminum silicate, beryllium aluminum silicate, sodium silicate, calcium orthosilicate, calcium metasilicate, calcium sodium silicate, zirconium silicate, magnesium orthosilicate, magnesium metasilicate, manganese silicate, barium silicate; Metal ion-exchanged silica-based compounds such as magnesium ion-exchanged silica, calcium ion-exchanged silica; Condensed phosphate metal compounds such as aluminum dihydrogen tripolyphosphate, magnesium oxide composite of aluminum dihydrogen tripolyphosphate, aluminum tripolyphosphate, zinc oxide composite of aluminum dihydrogen tripolyphosphate, etc.; Vanadium-based metal compounds such as vanadium pentoxide, calcium vanadate, magnesium vanadate, ammonium metavanadate, fired product of manganese oxide and vanadium oxide, fired product of calcium phosphate and vanadium oxide, etc.; Aluminum molybdate, calcium molybdate, aluminum phosphomolybdate, etc. of molybdate-based metal compounds; Zinc-based compounds such as zinc and zinc oxide; Silica-based compounds such as silica and colloidal silica; Composite metal iron oxides such as composite iron oxide of iron oxide and magnesium oxide, composite iron oxide of iron oxide and calcium oxide, composite iron oxide of iron oxide and zinc oxide, etc.; Sulfur-containing organic compounds such as triazole compounds, thiol compounds, thiadiazole compounds, thiazole compounds, etc.; and the like can be mentioned.

[0121] When the coating of the present invention contains the above rust inhibitor, the blending amount of the rust inhibitor is preferably in the range of 1 part by mass or more, 3 parts by mass or more, 70 parts by mass or less, and 60 parts by mass or less based on 100 parts by mass of the non-volatile content of the active hydrogen-containing compound.

[0122] As the catalyst, conventionally known compounds for coating can be used. Specifically, organometallic compounds and amine compounds can be mentioned.

[0123] Examples of the organometallic compound include diacetyltin diacetate, diacetyltin dioctoate, dioctyltin diacetate, dioctyltin bis(2-ethylhexanoate), dioctyltin dilaurate, dioctyltin dineodecanoate, dioctyltin oxide, dibutyltin diacetate, dibutyltin bis(2-ethylhexanoate), dibutyltin dioctoate, dibutyltin dilaurate, dibutyltin oxide, dibutyltin sulfide, dibutyltin fatty acid salt, tin octylate, zinc octylate, zinc naphthenate, fatty acid zincs, bismuth octanoate, bismuth 2-ethylhexanoate, bismuth oleate, bismuth neodecanoate, bismuth versatate, bismuth naphthenate, cobalt naphthenate, calcium octylate, copper naphthenate, tetra(2-ethylhexyl) titanate, and the like.

[0124] Examples of the amine compound include aliphatic amines such as trimethylamine, triethylamine, 2-(dimethylamino)ethyl methacrylate, 1,4-diazabicyclo[2.2.2]octane, 1,8-diazabicyclo[5.4.0]-7-undecene, 1,5-diazabicyclo[4.3.0]-5-nonene, 1-methylpiperidine, 1-methylpyrrolidine, pyridine, 4-dimethylaminopyridine, 4-(1-piperidyl)pyridine, N-methylimidazole, N,N-dimethylaniline, and the like.

[0125] When the coating of the present invention contains the above catalyst, the content of the catalyst is preferably in the range of 0.005% by mass or more, 0.01% by mass or more, 2% by mass or less, and 1% by mass or less based on the nonvolatile mass of the active hydrogen group-containing compound.

[0126] Examples of the coloring pigment include titanium oxide, zinc white, carbon black, red iron oxide, cadmium red, molybdenum red, chrome yellow, chromium oxide, Prussian blue, cobalt blue, azo pigment, phthalocyanine pigment, quinacridone pigment, isoindoline pigment, perylene pigment, and the like.

[0127] Examples of the extender pigment include talc, clay, kaolin, barite, barium sulfate, barium carbonate, calcium carbonate, alumina white, and the like.

[0128] Examples of the bright pigment include aluminum pigment, mica pigment, mica pigment coated with titanium oxide, aluminum oxide pigment coated with titanium oxide, and the like.

[0129] Examples of the dehydrating agent include compounds that consume water by chemically reacting with water or compounds that physically adsorb water. For example, as the former, trimethyl orthoformate, triethyl orthoformate, trimethyl orthoacetate, triethyl orthoacetate, toluenesulfonyl isocyanate, vinyltrimethoxysilane, vinyltriethoxysilane, and the like can be mentioned, and as the latter, zeolite, molecular sieve, and the like can be mentioned.

[0130] <Coating> Since the modified polyisocyanate of the present invention has excellent adhesion to a metal substrate, a coating containing the same is used for coating a metal substrate. The metal substrate includes both iron substrates and non-ferrous metals. Specific examples include steel, zinc-plated steel, stainless steel, magnesium alloy, aluminum, aluminum alloy, and the like. These may be subjected to surface treatment such as a phosphate-based or chromate-based treatment. In addition, those in which an old coating film or rust remains on the surface of a metal member constituting an existing structure are also included in the metal substrate.

[0131] The coating of the present invention can be diluted to a viscosity suitable for coating with an organic solvent or the like as necessary, and can be coated by methods such as air spray coating, airless spray coating, electrostatic coating, brush coating, roller coating, lysing gun, universal gun, and the like. As the drying method, it can be dried at room temperature, but heating drying is also possible. Room temperature varies depending on the atmospheric temperature of the environment where the coating is performed, but refers to a temperature without temperature operations such as forced heating or cooling, and heating drying refers to a temperature at which a forced heating operation using equipment such as a drying furnace is performed.

[0132] Since the coating of the present invention has excellent adhesion, it is possible to omit the application of a primer paint before applying the coating. Further, since the coating of the present invention also has excellent weather resistance, it is also possible to omit the application of a topcoat paint on top of the coated coating. Since the coating of the present invention can form a protective coating film excellent in corrosion resistance and weather resistance alone on a metal substrate, a single-layer finish is possible, and it is also applicable as a paint for one coat. Therefore, the present invention provides a cured product of the coating described above. The cured product can be used as a protective coating film. Further, the present invention also provides a coated article in which the cured product of the coating described above is formed on a substrate (a coated article including a substrate and the cured product of the coating described above disposed on the substrate). As the coated article, a coated metal material or the like in which the cured product of the coating described above is formed on a metal substrate is preferable.

Examples

[0133] Hereinafter, the present invention will be further described with reference to examples. However, the present invention is not limited to only these examples. Here, 'parts' and '%' mean'mass parts' and'mass %', respectively.

[0134] [Production of a modified polyisocyanate curing agent solution using an alkyl ester of an unsaturated dicarboxylic acid] Example 1 179 parts of 3-aminopropyltrimethoxysilane and 0.07 part of methoquinone were placed in a flask, heated to 80°C, air was introduced into the liquid to cause bubbling, and the mixture was stirred. 220 parts of di-i-propyl fumarate were added dropwise thereto over 2 hours, and then the mixture was held at 80°C for 1 hour and further aged at 50°C for 1 week to obtain 399 parts of a mixture containing 95% of 3-(N-(1,2-bis(i-propoxycarbonyl)ethyl)amino)propyltrimethoxysilane (in the alkoxysilane N-position modified product represented by the formula (5), R 2 is a methyl group, R 3 is a propylene group, R 4 and R 5 are both i-propyl groups, and n is 0). Into another flask, 400 parts of mineral spirit, 320 parts of "Swazol 1000" (a naphtha-based solvent, manufactured by Maruzen Petrochemical Co., Ltd., trade name), and 550 parts of "Durabonate TSA-100" (hexamethylene diisocyanate-based modified isocyanurate type polyisocyanate, manufactured by Asahi Kasei Corporation, trade name, isocyanate group content 20.6 wt%) were placed and stirred at room temperature. To this, 359 parts of a mixture containing 95% of 3-(N-(1,2-bis(i-propoxycarbonyl)ethyl)aminopropyl)trimethoxysilane was added dropwise over 2 hours, then held at 60 °C for 1 hour, cooled to room temperature, and a polyisocyanate curing agent solution (HE-1) with a non-volatile content concentration of 55% was obtained. The concentration of isocyanate groups contained in 1 g of the curing agent solution (HE-1) was 1.10 mmol / g (2.02 mmol / g in terms of non-volatile content).

[0135] Example 2 179 parts of 3-aminopropyltrimethoxysilane and 0.07 part of methoquinone were placed in a flask, heated to 80 °C, air was introduced into the liquid to cause bubbling and stirring. To this, 251 parts of di(1-methylpropyl) fumarate was added dropwise over 2 hours, then held at 80 °C for 1 hour, and further aged at 50 °C for 1 week, 3-(N-(1,2-bis(1-methylpropoxycarbonyl)ethyl)aminopropyl)trimethoxysilane (in the alkoxysilane N-position modified product represented by formula (5), R 2 is a methyl group, R 3 is a propylene group, R 4 and R 5A mixture containing 95% of the compound (where both R and R' are 1-methylpropyl groups and n is 0) was obtained in an amount of 430 parts. In another flask, 400 parts of mineral spirit, 320 parts of "Swazol 1000" (a naphtha-based solvent, manufactured by Maruzen Petrochemical Co., Ltd., trade name), and 550 parts of "Duronate TSA-100" (hexamethylene diisocyanate-modified isocyanurate type polyisocyanate, manufactured by Asahi Kasei Corporation, trade name, isocyanate group content 20.6 wt%) were placed and stirred at room temperature. To this, 387 parts of a mixture containing 95% of 3-(N-(1,2-bis(1-methylpropoxycarbonyl)ethyl)aminopropyl)trimethoxysilane was added dropwise over 2 hours, then held at 60°C for 1 hour, cooled to room temperature, and a polyisocyanate curing agent solution (HE-2) with a non-volatile content concentration of 55% was obtained. The concentration of isocyanate groups contained in 1 g of the curing agent solution (HE-2) was 1.08 mmol / g (1.96 mmol / g in terms of non-volatile content).

[0136] Example 3 89.5 parts of 3-aminopropyltrimethoxysilane and 0.04 part of methoquinone were placed in a flask, heated to 80°C, air was introduced into the liquid for bubbling and stirring. 110 parts of di-i-propyl fumarate was added dropwise thereto over 2 hours, then held at 80°C for 1 hour, and further aged at 50°C for 1 week to obtain 3-(N-(1,2-bis(i-propoxycarbonyl)ethyl)aminopropyl)trimethoxysilane (in the alkoxysilane N-position modified product represented by formula (5), where R 2 is a methyl group, R 3 is a propylene group, R 4 and R 5A mixture containing 95% of the compound where both are i-propyl groups and n is 0 (199 parts) was obtained. In another flask, 320 parts of mineral spirit, 256 parts of "Swazol 1000" (a naphtha-based solvent, manufactured by Maruzen Petrochemical Co., Ltd., trade name), and 550 parts of "Duraneate TSA-100" (hexamethylene diisocyanate-modified isocyanurate type polyisocyanate, manufactured by Asahi Kasei Corporation, trade name, isocyanate group content 20.6 wt%) were placed and stirred at room temperature. To this, 162 parts of the mixture containing 95% of 3-(N-(1,2-bis(i-propoxycarbonyl)ethyl)amino)propyltrimethoxysilane was added dropwise over 2 hours, then held at 60°C for 1 hour, cooled to room temperature, and a polyisocyanate curing agent solution (HE-3) with a non-volatile content concentration of 55% was obtained. The concentration of isocyanate groups contained in 1 g of the curing agent solution (HE-3) was 1.78 mmol / g (3.26 mmol / g in terms of non-volatile content).

[0137] Example 4 89.5 parts of 3-aminopropyltrimethoxysilane and 0.04 part of methoquinone were placed in a flask, heated to 80°C, air was introduced into the liquid for bubbling and stirring. 110 parts of di-i-propyl fumarate was added dropwise thereto over 2 hours, then held at 80°C for 1 hour, and further aged at 50°C for 1 week to obtain 3-(N-(1,2-bis(i-propoxycarbonyl)ethyl)amino)propyltrimethoxysilane (in the alkoxysilane N-position modified product represented by formula (5), R 2 is a methyl group, R 3 is a propylene group, R 4 and R 5A mixture containing 95% of the compound where both R and R are i-propyl groups and n is 0 (199 parts) was obtained. In another flask, 280 parts of mineral spirit, 224 parts of "Swazol 1000" (a naphtha-based solvent, manufactured by Maruzen Petrochemical Co., Ltd., trade name), and 550 parts of "Duranate TSA-100" (hexamethylene diisocyanate-modified isocyanurate type polyisocyanate, manufactured by Asahi Kasei Corporation, trade name, isocyanate group content 20.6 wt%) were placed and stirred at room temperature. To this, 108 parts of the mixture containing 95% of 3-(N-(1,2-bis(i-propoxycarbonyl)ethyl)amino)propyltrimethoxysilane was added dropwise over 2 hours, then held at 60°C for 1 hour, cooled to room temperature, and a polyisocyanate curing agent solution (HE-4) with a non-volatile content concentration of 56% was obtained. The concentration of isocyanate groups contained in 1 g of the curing agent solution (HE-4) was 2.09 mmol / g (3.72 mmol / g in terms of non-volatile content).

[0138] Example 5 221 parts of 3-aminopropyltriethoxysilane and 0.07 part of methoquinone were placed in a flask, heated to 80°C, air was introduced into the liquid for bubbling and stirring. 220 parts of di-i-propyl fumarate was added dropwise thereto over 2 hours, then held at 80°C for 1 hour, and further aged at 50°C for 1 week to obtain 3-(N-(1,2-bis(i-propoxycarbonyl)ethyl)amino)propyltriethoxysilane (in the alkoxysilane N-position modified product represented by formula (5), R 2 is an ethyl group, R 3 is a propylene group, R 4 and R 5A mixture (441 parts) containing 95% of the compound where both R and R are isopropyl groups and n is 0 was obtained. In another flask, 400 parts of mineral spirit, 320 parts of "Swazol 1000" (a naphtha-based solvent, manufactured by Maruzen Petrochemical Co., Ltd., trade name), and 550 parts of "Duronate TSA-100" (hexamethylene diisocyanate-modified isocyanurate type polyisocyanate, manufactured by Asahi Kasei Corporation, trade name, isocyanate group content 20.6 wt%) were placed and stirred at room temperature. To this, 397 parts of the mixture containing 95% of 3-(N-(1,2-bis(isopropoxycarbonyl)ethyl)amino)propyltriethoxysilane was added dropwise over 2 hours, then held at 60°C for 1 hour, cooled to room temperature, and a polyisocyanate curing agent solution (HE-5) with a non-volatile content concentration of 56% was obtained. The concentration of isocyanate groups contained in 1 g of the curing agent solution (HE-5) was 1.08 mmol / g (1.94 mmol / g in terms of non-volatile content).

[0139] Example 6 179 parts of 3-aminopropyltrimethoxysilane and 0.07 part of methoquinone were placed in a flask, heated to 80°C, air was introduced into the liquid for bubbling and stirring. 260 parts of diisopropyl fumarate was added dropwise thereto over 2 hours, then held at 80°C for 1 hour, and further aged at 50°C for 1 week to obtain 439 parts of a mixture containing 86% of 3-(N-(1,2-bis(isopropoxycarbonyl)ethyl)amino)propyltrimethoxysilane (in the alkoxysilane N-position modified product represented by formula (5), where R 2 is a methyl group, R 3 is a propylene group, R 4 and R 5 are both isopropyl groups and n is 0). Into another flask, 400 parts of mineral spirit, 280 parts of "Swazol 1000" (a naphtha-based solvent, manufactured by Maruzen Petrochemical Co., Ltd., trade name), and 550 parts of "Durabonate TSA-100" (hexamethylene diisocyanate-based modified isocyanurate type polyisocyanate, manufactured by Asahi Kasei Corporation, trade name, isocyanate group content 20.6 wt%) were placed and stirred at room temperature. To this, 394 parts of a mixture containing 86% of 3-(N-(1,2-bis(i-propoxycarbonyl)ethyl)aminopropyl)trimethoxysilane was added dropwise over 2 hours, then held at 60 °C for 1 hour, cooled to room temperature, and a polyisocyanate curing agent solution (HE-6) with a non-volatile content concentration of 55% was obtained. The concentration of isocyanate groups contained in 1 g of the curing agent solution (HE-6) was 1.11 mmol / g (2.03 mmol / g in terms of non-volatile content).

[0140] Example 7 179 parts of 3-aminopropyltrimethoxysilane and 0.07 part of methoquinone were placed in a flask, heated to 80 °C, air was introduced into the liquid for bubbling and stirring. To this, 180 parts of di-i-propyl fumarate was added dropwise over 2 hours, then held at 80 °C for 1 hour, and further aged at 50 °C for 1 week to obtain 359 parts of a mixture containing 99% of 3-(N-(1,2-bis(i-propoxycarbonyl)ethyl)aminopropyl)trimethoxysilane (in the alkoxysilane N-position modified product represented by formula (5), where R 2 is a methyl group, R 3 is a propylene group, R 4 and R 5 are both i-propyl groups, and n is 0). Into another flask, 400 parts of mineral spirit, 320 parts of "Swazol 1000" (a naphtha-based solvent, manufactured by Maruzen Petrochemical Co., Ltd., trade name), and 550 parts of "Duronate TSA-100" (hexamethylene diisocyanate-based modified isocyanurate type polyisocyanate, manufactured by Asahi Kasei Corporation, trade name, isocyanate group content 20.6 wt%) were placed and stirred at room temperature. To this, 323 parts of a mixture containing 99% of 3-(N-(1,2-bis(i-propoxycarbonyl)ethyl)aminopropyl)trimethoxysilane was added dropwise over 2 hours, then held at 60 °C for 1 hour, cooled to room temperature, and a polyisocyanate curing agent solution (HE-7) with a non-volatile content concentration of 55% was obtained. The concentration of isocyanate groups contained in 1 g of the curing agent solution (HE-7) was 1.13 mmol / g (2.06 mmol / g in terms of non-volatile content).

[0141] Comparative Example 1 179 parts of 3-aminopropyltrimethoxysilane and 0.07 part of methoquinone were placed in a flask, heated to 80 °C, air was introduced into the liquid for bubbling and stirring. To this, 189 parts of diethyl fumarate was added dropwise over 2 hours, then held at 80 °C for 1 hour, and further aged at 50 °C for 1 week to obtain 368 parts of a mixture containing 95% of 3-(N-(1,2-bis(ethoxycarbonyl)ethyl)aminopropyl)trimethoxysilane (in the case of the alkoxysilane N-position modified product represented by formula (5), where R 2 is a methyl group, R 3 is a propylene group, R 4 and R 5 both correspond to an ethyl group, and n is 0). Into another flask, 400 parts of mineral spirit, 320 parts of "Swazol 1000" (a naphtha-based solvent, manufactured by Maruzen Petrochemical Co., Ltd., trade name), and 550 parts of "Duronate TSA-100" (hexamethylene diisocyanate-modified isocyanurate type polyisocyanate, manufactured by Asahi Kasei Corporation, trade name, isocyanate group content 20.6 wt%) were placed and stirred at room temperature. To this, 331 parts of a mixture containing 95% of 3-(N-(1,2-bis(ethoxycarbonyl)ethyl)amino)propyltrimethoxysilane was added dropwise over 2 hours, then held at 60 °C for 1 hour, cooled to room temperature, and a polyisocyanate curing agent solution (HR-1) modified with a linear alkyl ester of an unsaturated dicarboxylic acid (non-volatile content concentration 54%) was obtained. The concentration of isocyanate groups contained in 1 g of the curing agent solution (HR-1) was 1.12 mmol / g (2.08 mmol / g in terms of non-volatile content).

[0142] Comparative Example 2 179 parts of 3-aminopropyltrimethoxysilane and 0.07 part of methoquinone were placed in a flask, heated to 80 °C, air was introduced into the liquid for bubbling and stirring. To this, 251 parts of dibutyl maleate was added dropwise over 2 hours, then held at 80 °C for 1 hour, and further aged at 50 °C for 1 week to obtain 430 parts of a mixture containing 95% of 3-(N-(1,2-bis(butoxycarbonyl)ethyl)amino)propyltrimethoxysilane (in the case of the N-position modified product of the alkoxysilane represented by formula (5), where R 2 is a methyl group, R 3 is a propylene group, R 4 and R 5 both correspond to n-butyl groups and n is 0). Into another flask, 400 parts of mineral spirit, 320 parts of "Swazol 1000" (a naphtha-based solvent, manufactured by Maruzen Petrochemical Co., Ltd., trade name), and 550 parts of "Duranate TSA-100" (hexamethylene diisocyanate-based modified isocyanurate type polyisocyanate, manufactured by Asahi Kasei Corporation, trade name, isocyanate group content 20.6 wt%) were placed and stirred at room temperature. To this, 387 parts of a mixture containing 95% of 3-(N-(1,2-bis(butoxycarbonyl)ethyl)amino)propyltrimethoxysilane was added dropwise over 2 hours, then held at 60 °C for 2 hours, cooled to room temperature, and a polyisocyanate curing agent solution (HR-2) modified with a linear alkyl ester of an unsaturated dicarboxylic acid (non-volatile content concentration 55%) was obtained. The concentration of isocyanate groups contained in 1 g of the curing agent solution (HR-2) was 1.08 mmol / g (1.96 mmol / g in terms of non-volatile content).

[0143] Comparative Example 3 Into a container, 400 parts of mineral spirit, 320 parts of "Swazol 1000" (a naphtha-based solvent, manufactured by Maruzen Petrochemical Co., Ltd., trade name), and 880 parts of "Duranate TSA-100" (hexamethylene diisocyanate-based modified isocyanurate type polyisocyanate, manufactured by Asahi Kasei Corporation, trade name, isocyanate group content 20.6 wt%) were placed and stirred at room temperature, and a polyisocyanate curing agent solution (HR-3) not modified with an aminoalkoxysilane and a dialkyl ester of an unsaturated carboxylic acid (non-volatile content concentration 55%) was obtained. The concentration of isocyanate groups contained in 1 g of the curing agent solution (HR-3) was 2.70 mmol / g (4.90 mmol / g in terms of non-volatile content).

[0144] Comparative Example 4 179 parts of 3-aminopropyltrimethoxysilane and 0.07 part of methoquinone were placed in a flask, heated to 80 °C, air was introduced into the liquid for bubbling and stirred to obtain 179 parts of a mixture. Into another flask, 400 parts of mineral spirit, 180 parts of "Swazol 1000" (a naphtha-based solvent, manufactured by Maruzen Petrochemical Co., Ltd., trade name), and 550 parts of "Durabonate TSA-100" (hexamethylene diisocyanate-modified isocyanurate-type polyisocyanate, manufactured by Asahi Kasei Corporation, trade name, isocyanate group content 20.6 wt%) were placed and stirred at room temperature. To this, 161 parts of the above mixture containing 3-aminopropyltrimethoxysilane was added dropwise over 2 hours, and then held at 60°C for 1 hour and cooled to room temperature. An attempt was made to obtain a polyisocyanate curing agent solution (HR-4) that was modified with aminoalkoxysilane but unmodified with unsaturated carboxylic acid dialkyl ester (non-volatile content concentration was 54%), but the curing agent precipitated and became non-uniform, and thus could not be used as a curing agent solution. Therefore, subsequent evaluations were aborted. The concentration of isocyanate groups contained in 1 g of the curing agent solution (HR-4) was 1.39 mmol / g (2.56 mmol / g in terms of non-volatile content).

[0145] Table 1 below shows the composition, blending molar ratio or reaction molar ratio, state, and NCO residual ratio of each curing agent solution obtained in the examples and comparative examples.

[0146]

Table 1

[0147] (Note 1) Primary amino group / unsaturated carbon-carbon bond The actual reaction molar ratio: represents the molar ratio of aminoalkoxysilane added to the unsaturated carboxylic acid dialkyl ester. When the unsaturated carboxylic acid dialkyl ester is blended in excess, the excess portion does not undergo an addition reaction and becomes an unreacted substance, so the numerical values differ between the reaction ratio and the blending ratio. (Note 2) Amino group / isocyanate group reaction molar ratio: The amino group here represents the total amount of amino groups, that is, the total amount of primary amino groups derived from alkoxysilane having unreacted amino groups and 1,2-bis(alkoxycarbonyl)ethylamino groups.

[0148] [Evaluation items] (*) State of the curing agent solution Each hardener solution was sealed in a 250 ml glass bottle and evaluated according to the following criteria. In the table, a ○ rank was judged as qualified, and an × or ×× rank was judged as unqualified. The states immediately after initial production (right after production) and after storage for 1 year in a constant temperature chamber under an atmosphere of 25°C and 60% humidity while sealed were visually observed respectively. ○: No two-layer separation, cloudiness, or precipitate was observed in the hardener solution, and there was no abnormality. ×: Either two-layer separation or cloudiness was observed in the hardener solution. ××: The hardener precipitated from the hardener solution. (*) Residual NCO ratio in the hardener solution For the polyisocyanate hardener solutions obtained in Examples 1 to 7 and Comparative Examples 1 to 4, it was calculated by the following formula. The larger the value, the better. [(Total number of moles of NCO groups contained in the hardener solution 12 months after the production of the hardener solution) / (Total number of moles of NCO groups contained in the hardener solution immediately after the production of the hardener solution)] × 100 (%) The storage conditions were 25°C and 60% humidity. The total number of moles of NCO groups was calculated by adding 10 ml of 0.1 mol / L dibutylamine solution to 0.1 g of the sample to react the NCO groups, and then titrating the remaining dibutylamine with an aqueous hydrochloric acid solution using bromophenol blue as a titration indicator.

[0149] [Production of a modified polyisocyanate hardener solution using an alkyl ester of an unsaturated monocarboxylic acid] Example 8 179 parts of 3-aminopropyltrimethoxysilane, 0.07 part of methoquinone, and 6 parts of "Swazol 1000" (a naphtha-based solvent, manufactured by Maruzen Petrochemical Co., Ltd., trade name) were placed in a flask. Air was introduced into the liquid for bubbling and stirring, and 128 parts of i-butyl acrylate was added dropwise thereto over 2 hours and then held at 50°C for 1 hour. Further, it was aged at 50°C for 1 week, and 3-(N-(2-(i-butyloxycarbonyl)ethyl)amino)propyltrimethoxysilane (in the alkoxysilane N-position modified product represented by the formula (6), R 2 is a methyl group, R 3 is a propylene group, R 6(Compound where i is an i-butyl group and n is 0) / 3-aminopropyltrimethoxysilane / 3-(N,N-di(2-(i-butyloxycarbonyl)ethyl)amino)propyltrimethoxysilane (In the compound represented by formula (8), R 2 is a methyl group, R 3 is a propylene group, R 6 is an i-butyl group and n is 0), 313 parts of a mixture containing them in a molar ratio of 74 / 13 / 13 was obtained. The total amount of (primary amino group + secondary amino group) in 1 g of the mixture was 2.78 mmol. In another flask, 282 parts of mineral spirit, 231 parts of "Swazol 1000" (a naphtha-based solvent, manufactured by Maruzen Petrochemical Co., Ltd., trade name), and 500 parts of "Duranate TSA-100" (hexamethylene diisocyanate-based modified isocyanurate type polyisocyanate, manufactured by Asahi Kasei Corporation, trade name, isocyanate group content 20.6 wt%) were placed and stirred at room temperature. To this, 132 parts of a mixture containing 3-(N-(2-(i-butyloxycarbonyl)ethyl)amino)propyltrimethoxysilane / 3-aminopropyltrimethoxysilane / 3-(N,N-di(2-(i-butyloxycarbonyl)ethyl)amino)propyltrimethoxysilane in a molar ratio of 74 / 13 / 13 was added dropwise over 2 hours, then held at 60 °C for 2 hours, cooled to room temperature, and a polyisocyanate curing agent solution (HE-8) with a non-volatile content concentration of 55% was obtained. The concentration of isocyanate groups contained in the curing agent solution (HE-8) was 1.82 mmol / g (3.31 mmol / g in terms of non-volatile content).

[0150] Example 9 179 parts of 3-aminopropyltrimethoxysilane, 0.07 part of methoquinone, and 6 parts of "Swazol 1000" (a naphtha-based solvent, manufactured by Maruzen Petrochemical Co., Ltd., trade name) were placed in a flask, air was introduced into the liquid for bubbling and stirring, and 128 parts of t-butyl acrylate was added dropwise over 2 hours and then held at 50 °C for 1 hour. Further aged at 50 °C for 1 week, 3-(N-(2-(t-butyloxycarbonyl)ethyl)amino)propyltrimethoxysilane (In the alkoxysilane N-position modified product represented by formula (6), R 2 is a methyl group, R 3is a propylene group, R 6 (compound where R is a t-butyl group and n is 0) / 3-aminopropyltrimethoxysilane / 3-(N,N-di(2-(t-butoxycarbonyl)ethyl)amino)propyltrimethoxysilane (in the compound represented by formula (8), R 2 is a methyl group, R 3 is a propylene group, R 6 (compound where R is a t-butyl group and n is 0)) to obtain 313 parts of a mixture containing them in a molar ratio of 78 / 11 / 11. The total amount of (primary amino group + secondary amino group) in 1 g of the mixture was 2.84 mmol. In another flask, 281 parts of mineral spirit, 230 parts of "Swazol 1000" (a naphtha-based solvent, manufactured by Maruzen Petrochemical Co., Ltd., trade name), and 500 parts of "Duronate TSA-100" were placed and stirred at room temperature. To this, 130 parts of a mixture containing 3-(N-(2-(t-butoxycarbonyl)ethyl)amino)propyltrimethoxysilane / 3-aminopropyltrimethoxysilane / 3-(N,N-di(2-(t-butoxycarbonyl)ethyl)amino)propyltrimethoxysilane in a molar ratio of 78 / 11 / 11 was added dropwise over 2 hours, then held at 60°C for 2 hours, cooled to room temperature, to obtain a polyisocyanate curing agent solution (HE-9) with a non-volatile content concentration of 55%. The concentration of isocyanate groups contained in the curing agent solution (HE-9) was 1.83 mmol / g (3.32 mmol / g in terms of non-volatile content).

[0151] Example 10 89.5 parts of 3-aminopropyltrimethoxysilane, 0.04 part of methoquinone, and 4 parts of "Swazol 1000" (a naphtha-based solvent, manufactured by Maruzen Petrochemical Co., Ltd., trade name) were placed in a flask, air was introduced into the liquid for bubbling and stirring, and 92 parts of 2-ethylhexyl acrylate was added dropwise thereto over 2 hours and then held at 50°C for 1 hour. Further, it was aged at 50°C for 1 week, and 3-(N-(2-(2-ethylhexyloxycarbonyl)ethyl)amino)propyltrimethoxysilane (in the alkoxysilane N-position modified product represented by formula (6), R 2 is a methyl group, R 3 is a propylene group, R 6(Compound where R is a 2-ethylhexyl group and n is 0) / 3-aminopropyltrimethoxysilane / 3-(N,N-di(2-(2-ethylhexyloxycarbonyl)ethyl)amino)propyltrimethoxysilane (in the compound represented by formula (8), R 2 is a methyl group, R 3 is a propylene group, R 6 is a 2-ethylhexyl group and n is 0) / 3-aminopropyltrimethoxysilane / 3-(N,N-di(2-(2-ethylhexyloxycarbonyl)ethyl)amino)propyltrimethoxysilane (in the compound represented by formula (8), R In another flask, 296 parts of mineral spirit, 242 parts of "Swazol 1000" (a naphtha-based solvent, manufactured by Maruzen Petrochemical Co., Ltd., trade name), and 500 parts of "Duronate TSA-100" were placed and stirred at room temperature. To this, 164 parts of a mixture containing 3-(N-(2-(2-ethylhexyloxycarbonyl)ethyl)amino)propyltrimethoxysilane / 3-aminopropyltrimethoxysilane / 3-(N,N-di(2-(2-ethylhexyloxycarbonyl)ethyl)amino)propyltrimethoxysilane in a molar ratio of 66 / 17 / 17 was added dropwise over 2 hours, and then held at 60 °C for 2 hours, cooled to room temperature, and a polyisocyanate curing agent solution (HE-10) with a non-volatile content concentration of 55% was obtained. The concentration of isocyanate groups contained in the curing agent solution (HE-10) was 1.73 mmol / g (3.15 mmol / g in terms of non-volatile content).

[0152] Example 11 89.5 parts of 3-aminopropyltrimethoxysilane, 0.04 part of methoquinone, and 4 parts of "Swazol 1000" (a naphtha-based solvent, manufactured by Maruzen Petrochemical Co., Ltd., trade name) were placed in a flask, air was introduced into the liquid for bubbling and stirring, and 104 parts of isobornyl acrylate was added dropwise thereto over 2 hours and then held at 50 °C for 1 hour. Further, aging was carried out at 50 °C for 1 week, and 3-(N-(2-(isobornyloxycarbonyl)ethyl)amino)propyltrimethoxysilane (in the alkoxysilane N-position modified product represented by formula (6), R 2 is a methyl group, R 3 is a propylene group, R 6(Compound where R is an isobornyl group and n is 0) / 3-aminopropyltrimethoxysilane / 3-(N,N-di(2-(isobornyloxycarbonyl)ethyl)amino)propyltrimethoxysilane (in the compound represented by formula (8), R 2 is a methyl group, R 3 is a propylene group, R 6 is an isobornyl group, and n is 0), 198 parts of a mixture containing them in a molar ratio of 74 / 13 / 13 was obtained. The total amount of (primary amino group + secondary amino group) in 1 g of the mixture was 2.20 mmol. In another flask, 297 parts of mineral spirit, 243 parts of "Swazol 1000" (a naphtha-based solvent, manufactured by Maruzen Petrochemical Co., Ltd., trade name), and 500 parts of "Duronate TSA-100" were put in and stirred at room temperature. To this, 167 parts of a mixture containing 3-(N-(2-(isobornyloxycarbonyl)ethyl)amino)propyltrimethoxysilane / 3-aminopropyltrimethoxysilane / 3-(N,N-di(2-(isobornyloxycarbonyl)ethyl)amino)propyltrimethoxysilane in a molar ratio of 74 / 13 / 13 was added dropwise over 2 hours, then held at 60 °C for 2 hours, cooled to room temperature, and a polyisocyanate curing agent solution (HE-11) with a non-volatile content concentration of 55% was obtained. The concentration of isocyanate groups contained in the curing agent solution (HE-11) was 1.73 mmol / g (3.14 mmol / g in terms of non-volatile content).

[0153] Example 12 221 parts of 3-aminopropyltriethoxysilane, 0.07 part of methoquinone, and 7 parts of "Swazol 1000" (a naphtha-based solvent, manufactured by Maruzen Petrochemical Co., Ltd., trade name) were put into a flask, air was introduced into the liquid for bubbling and stirred, and 128 parts of i-butyl acrylate was added dropwise thereto over 2 hours and then held at 50 °C for 1 hour. Further aged at 50 °C for 1 week, 3-(N-(2-(i-butyloxycarbonyl)ethyl)amino)propyltrimethoxysilane (in the alkoxysilane N-position modified product represented by formula (6), R 2 is a methyl group, R 3 is a propylene group, R 6(Compound where i is an i-butyl group and n is 0) / 3-aminopropyltrimethoxysilane / 3-(N,N-di(2-(i-butyloxycarbonyl)ethyl)amino)propyltrimethoxysilane (in the compound represented by formula (8), R 2 is a methyl group, R 3 is a propylene group, R 6 is an i-butyl group and n is 0) / 3-aminopropyltrimethoxysilane / 3-(N,N-di(2-(i-butyloxycarbonyl)ethyl)amino)propyltrimethoxysilane (in the compound represented by formula (8), R

[0154] Example 13 179 parts of 3-aminopropyltrimethoxysilane, 0.07 part of methoquinone, and 6 parts of "Swazol 1000" (a naphtha-based solvent, trade name, manufactured by Maruzen Petrochemical Co., Ltd.) were placed in a flask. Air was introduced into the liquid for bubbling and stirring, and 128 parts of t-butyl acrylate were added dropwise thereto over 2 hours, followed by holding at 50°C for 1 hour. Further aging was carried out at 50°C for 1 week to obtain 3-(N-(2-(t-butyloxycarbonyl)ethyl)amino)propyltrimethoxysilane (in the alkoxysilane N-position modified product represented by formula (6), R 2 is a methyl group, R 3 is a propylene group, R 6(Compound where R is a t-butyl group and n is 0) / 3-aminopropyltrimethoxysilane / 3-(N,N-di(2-(t-butoxycarbonyl)ethyl)amino)propyltrimethoxysilane (in the compound represented by formula (8), R 2 is a methyl group, R 3 is a propylene group, R 6 is a t-butyl group and n is 0), 313 parts of a mixture containing them in a molar ratio of 78 / 11 / 11 was obtained. The total amount of (primary amino group + secondary amino group) in 1 g of the mixture was 2.84 millimoles. In another flask, 348 parts of mineral spirit, 284 parts of "Swazol 1000" (a naphtha-based solvent, manufactured by Maruzen Petrochemical Co., Ltd., trade name), and 500 parts of "Duraneate TSA-100" were put and stirred at room temperature. To this, 285 parts of a mixture containing 3-(N-(2-(t-butoxycarbonyl)ethyl)amino)propyltrimethoxysilane / 3-aminopropyltrimethoxysilane / 3-(N,N-di(2-(t-butoxycarbonyl)ethyl)amino)propyltrimethoxysilane in a molar ratio of 78 / 11 / 11 was added dropwise over 2 hours, then held at 60 °C for 2 hours, cooled to room temperature, and a polyisocyanate curing agent solution (HE-13) with a non-volatile content concentration of 55% was obtained. The concentration of isocyanate groups contained in the curing agent solution (HE-13) was 1.16 millimoles / g (2.11 millimoles / g in terms of non-volatile content).

[0155] Example 14 89.5 parts of 3-aminopropyltrimethoxysilane, 0.04 part of methoquinone, and 4 parts of "Swazol 1000" (a naphtha-based solvent, manufactured by Maruzen Petrochemical Co., Ltd., trade name) were put into a flask, air was introduced into the liquid for bubbling and stirring, and 104 parts of isobornyl acrylate was added dropwise thereto over 2 hours and then held at 50 °C for 1 hour. Further aged at 50 °C for 1 week, 3-(N-(2-(isobornyloxycarbonyl)ethyl)amino)propyltrimethoxysilane (in the alkoxysilane N-position modified product represented by formula (6), R 2 is a methyl group, R 3 is a propylene group, R 6(Compound where R is an isobornyl group and n is 0) / 3-aminopropyltrimethoxysilane / 3-(N,N-di(2-(isobornyloxycarbonyl)ethyl)amino)propyltrimethoxysilane (in the compound represented by formula (8), R 2 is a methyl group, R 3 is a propylene group, R 6 is an isobornyl group, and n is 0), 198 parts of a mixture containing them in a molar ratio of 74 / 13 / 13 was obtained. The total amount of (primary amino group + secondary amino group) in 1 g of the mixture was 2.20 mmol. In another flask, 273 parts of mineral spirit, 223 parts of "Swazol 1000" (a naphtha-based solvent, manufactured by Maruzen Petrochemical Co., Ltd., trade name), and 500 parts of "Duronate TSA-100" were put in and stirred at room temperature. To this, 111 parts of a mixture containing 3-(N-(2-(isobornyloxycarbonyl)ethyl)amino)propyltrimethoxysilane / 3-aminopropyltrimethoxysilane / 3-(N,N-di(2-(isobornyloxycarbonyl)ethyl)amino)propyltrimethoxysilane in a molar ratio of 74 / 13 / 13 was added dropwise over 2 hours, then held at 60 °C for 2 hours, cooled to room temperature, and a polyisocyanate curing agent solution (HE-14) with a non-volatile content concentration of 55% was obtained. The concentration of isocyanate groups contained in the curing agent solution (HE14) was 1.99 mmol / g (3.62 mmol / g in terms of non-volatile content).

[0156] Example 15 179 parts of 3-aminopropyltrimethoxysilane, 0.07 part of methoquinone, and 6 parts of "Swazol 1000" (a naphtha-based solvent, manufactured by Maruzen Petrochemical Co., Ltd., trade name) were put into a flask, air was introduced into the liquid for bubbling and stirring, and 141 parts of i-butyl acrylate was added dropwise thereto over 2 hours and then held at 50 °C for 1 hour. Further, it was aged at 50 °C for 1 week, and 3-(N-(2-(i-butyloxycarbonyl)ethyl)amino)propyltrimethoxysilane (in the alkoxysilane N-position modified product represented by formula (6), R 2 is a methyl group, R 3 is a propylene group, R 6(Compound where i is an i-butyl group and n is 0) / 3-aminopropyltrimethoxysilane / 3-(N,N-di(2-(i-butyloxycarbonyl)ethyl)amino)propyltrimethoxysilane (In the compound represented by formula (8), R 2 is a methyl group, R 3 is a propylene group, R 6 is an i-butyl group, n is 0 compound) / 3-aminopropyltrimethoxysilane / 3-(N,N-di(2-(i-butyloxycarbonyl)ethyl)amino)propyltrimethoxysilane (In the compound represented by formula (8), R In another flask, 308 parts of mineral spirit, 252 parts of "Swazol 1000" (a naphtha-based solvent, manufactured by Maruzen Petrochemical Co., Ltd., trade name), and 500 parts of "Duronate TSA-100" were placed and stirred at room temperature. To this, 192 parts of a mixture containing 3-(N-(2-(i-butyloxycarbonyl)ethyl)amino)propyltrimethoxysilane / 3-aminopropyltrimethoxysilane / 3-(N,N-di(2-(i-butyloxycarbonyl)ethyl)amino)propyltrimethoxysilane in a molar ratio of 77 / 6 / 17 was added dropwise over 2 hours, then held at 60°C for 2 hours, cooled to room temperature, and a polyisocyanate curing agent solution (HE-15) with a non-volatile content concentration of 55% was obtained. The concentration of isocyanate groups contained in the curing agent solution (HE-15) was 1.57 mmol / g (2.85 mmol / g in terms of non-volatile content).

[0157] Example 16 110.5 parts of 3-aminopropyltriethoxysilane, 0.04 part of methoquinone, and 4 parts of "Swazol 1000" (a naphtha-based solvent, manufactured by Maruzen Petrochemical Co., Ltd., trade name) were placed in a flask, air was introduced into the liquid for bubbling and stirring, and 93.6 parts of isobornyl acrylate was added dropwise thereto over 2 hours and then held at 50°C for 1 hour. Further aged at 50°C for 1 week, 3-(N-(2-(isobornyloxycarbonyl)ethyl)amino)propyltrimethoxysilane (In the alkoxysilane N-position modified product represented by formula (6), R 2 is a methyl group, R 3 is a propylene group, R 6(Compound where R is an isobornyl group and n is 0) / 3-aminopropyltrimethoxysilane / 3-(N,N-di(2-(isobornyloxycarbonyl)ethyl)amino)propyltrimethoxysilane (in the alkoxysilane N-position modified product represented by formula (8), R 2 is a methyl group, R 3 is a propylene group, R 6 is an isobornyl group and n is 0 compound) 208 parts of a mixture containing in a molar ratio of 80 / 15 / 5 was obtained. The total amount of (primary amino group + secondary amino group) in 1 g of the mixture was 2.28 mmol. In another flask, 271 parts of mineral spirit, 222 parts of "Swazol 1000" (a naphtha-based solvent, manufactured by Maruzen Petrochemical Co., Ltd., trade name), and 500 parts of "Duraneate TSA-100" were put and stirred at room temperature. To this, 108 parts of a mixture containing 3-(N-(2-(isobornyloxycarbonyl)ethyl)amino)propyltrimethoxysilane / 3-aminopropyltrimethoxysilane / 3-(N,N-di(2-(isobornyloxycarbonyl)ethyl)amino)propyltrimethoxysilane in a molar ratio of 80 / 15 / 15 was added dropwise over 2 hours, then held at 60 °C for 2 hours, cooled to room temperature, and a polyisocyanate curing agent solution (HE-16) with a non-volatile content concentration of 55% was obtained. The concentration of isocyanate groups contained in the curing agent solution (HE-16) was 2.01 mmol / g (3.65 mmol / g in terms of non-volatile content).

[0158] Comparative Example 5 179 parts of 3-aminopropyltrimethoxysilane, 0.07 part of methoquinone, and 6 parts of "Swazol 1000" (a naphtha-based solvent, manufactured by Maruzen Petrochemical Co., Ltd., trade name) were placed in a flask, air was introduced into the liquid for bubbling and stirred, and 128 parts of n-butyl acrylate was added dropwise thereto over 2 hours and then held at 50 °C for 1 hour. Further aged at 50 °C for 1 week, 3-(N-(2-(n-butyloxycarbonyl)ethyl)amino)propyltrimethoxysilane (in the alkoxysilane N-position modified product represented by formula (6), R 2 is a methyl group, R 3 is a propylene group, R 6(Compound where R is an n-butyl group and n is 0) / 3-aminopropyltrimethoxysilane / 3-(N,N-di(2-(n-butyloxycarbonyl)ethyl)amino)propyltrimethoxysilane (in the compound represented by formula (8), R 2 is a methyl group, R 3 is a propylene group, R 6 is a compound where R is an n-butyl group and n is 0) in a molar ratio of 66 / 17 / 17, 313 parts of the mixture was obtained. The total amount of (primary amino group + secondary amino group) in 1 g of the mixture was 2.65 mmol. In another flask, 285 parts of mineral spirit, 233 parts of "Swazol 1000" (a naphtha-based solvent, manufactured by Maruzen Petrochemical Co., Ltd., trade name), and 500 parts of "Duronate TSA-100" were put in and stirred at room temperature. To this, 139 parts of a mixture containing 3-(N-(2-(n-butyloxycarbonyl)ethyl)amino)propyltrimethoxysilane / 3-aminopropyltrimethoxysilane / 3-(N,N-di(2-(n-butyloxycarbonyl)ethyl)amino)propyltrimethoxysilane in a molar ratio of 66 / 17 / 17 was added dropwise over 2 hours, then held at 60°C for 2 hours, cooled to room temperature, and a polyisocyanate curing agent solution (HR-5) with a non-volatile content concentration of 55% was obtained. The concentration of isocyanate groups contained in the curing agent solution (HR-5) was 1.80 mmol / g (3.28 mmol / g in terms of non-volatile content).

[0159] Comparative Example 6 179 parts of 3-aminopropyltrimethoxysilane, 0.07 part of methoquinone, and 6 parts of "Swazol 1000" (a naphtha-based solvent, manufactured by Maruzen Petrochemical Co., Ltd., trade name) were put into a flask, air was introduced into the liquid for bubbling and stirring, and 100 parts of ethyl acrylate was added dropwise thereto over 2 hours and then held at 50°C for 1 hour. Further aged at 50°C for 1 week, 3-(N-(2-(ethyloxycarbonyl)ethyl)amino)propyltrimethoxysilane (in the alkoxysilane N-position modified product represented by formula (6), R 2 is a methyl group, R 3 is a propylene group, R 6(Compound where R is an ethyl group and n is 0) / 3-aminopropyltrimethoxysilane / 3-(N,N-di(2-(ethyloxycarbonyl)ethyl)amino)propyltrimethoxysilane (in the compound represented by formula (8), R 2 is a methyl group, R 3 is a propylene group, R 6 is an ethyl group, and n is 0), 285 parts of a mixture containing them in a molar ratio of 66 / 17 / 17 was obtained. The total amount of (primary amino group + secondary amino group) in 1 g of the mixture was 2.91 mmol. In another flask, 297 parts of mineral spirit, 243 parts of "Swazol 1000" (a naphtha-based solvent, manufactured by Maruzen Petrochemical Co., Ltd., trade name), and 500 parts of "Duronate TSA-100" were put in and stirred at room temperature. To this, 169 parts of a mixture containing 3-(N-(2-(ethyloxycarbonyl)ethyl)amino)propyltrimethoxysilane / 3-aminopropyltrimethoxysilane / 3-(N,N-di(2-(ethyloxycarbonyl)ethyl)amino)propyltrimethoxysilane in a molar ratio of 66 / 17 / 17 was added dropwise over 2 hours, then held at 60 °C for 2 hours, cooled to room temperature, and a polyisocyanate curing agent solution (HR-6) with a non-volatile content concentration of 55% was obtained. The concentration of isocyanate groups contained in the curing agent solution (HR-6) was 1.62 mmol / g (2.95 mmol / g in terms of non-volatile content).

[0160] Comparative Example 7 In a container, 225 parts of mineral spirit, 184 parts of "Swazol 1000" (a naphtha-based solvent, manufactured by Maruzen Petrochemical Co., Ltd., trade name), and 500 parts of "Duronate TSA-100" were put in and stirred at room temperature to obtain a polyisocyanate curing agent solution (HR-7) (non-volatile content concentration is 55%) that has not been modified with aminoalkoxysilane and unsaturated carboxylic acid dialkyl ester. The concentration of isocyanate groups contained in 1 g of the curing agent solution (HR-7) was 2.70 mmol / g (4.91 mmol / g in terms of non-volatile content).

[0161] Comparative Example 8 179 parts of 3-aminopropyltrimethoxysilane, 0.07 part of methoquinone, and 4 parts of "Swazol 1000" (a naphtha-based solvent, manufactured by Maruzen Petrochemical Co., Ltd., trade name) were placed in a flask, heated to 80 °C, air was introduced into the liquid for bubbling, and the mixture was stirred to obtain 183 parts of a mixture. In another flask, 254 parts of mineral spirit, 208 parts of "Swazol 1000" (a naphtha-based solvent, manufactured by Maruzen Petrochemical Co., Ltd., trade name), and 500 parts of "Duronate TSA-100" were added and stirred at room temperature. To this, 67 parts of the above mixture containing 3-aminopropyltrimethoxysilane was added dropwise over 2 hours, then held at 60 °C for 1 hour, cooled to room temperature, and an attempt was made to obtain a polyisocyanate curing agent solution (HR-8) that was modified with aminoalkoxysilane but unmodified with unsaturated carboxylic acid dialkyl ester (non-volatile content concentration: 54%). However, the curing agent precipitated and became non-uniform, so it could not be used as a curing agent solution, and the subsequent evaluation was aborted.

[0162]

Table 2

[0163] (Note 3) Molar ratio of 3-(N-(2-(alkoxycarbonyl)ethyl)amino)propyltrialkoxysilane / 3-aminopropyltrialkoxysilane / 3-(N,N-di(2-(alkoxycarbonyl)ethyl)amino)propyltrialkoxysilane in the mixture: Calculated by conversion from the proton integral value of 1H NMR (proton nuclear magnetic resonance analysis). [Evaluation Items] (*) State of the curing agent solution After each curing agent solution was prepared, it was sealed in a 250 ml glass bottle and visually observed for the state after storage in a constant temperature chamber at 20 °C and 60% humidity for 3 months under sealed conditions, and for the state after storage in a constant temperature chamber at 5 °C and 60% humidity for 2 weeks under sealed conditions. In the table, a ○ rank was judged as qualified, and × and ×× ranks were judged as unqualified. ○: No two-layer separation, turbidity, or precipitate was observed in the curing agent solution, and there was no abnormality. ×: Separation into two layers or turbidity is observed in the hardener solution. ××: A gummy polymer precipitates from the hardener solution.

[0164] [Production of Modified Polyisocyanate Using Saturated Carboxylic Acid Alkyl Ester] Example 17 89 parts of methyl acetate, which is a linear saturated ester, and 179 parts of 3-aminopropyltrimethoxysilane were placed in a flask under a nitrogen atmosphere and stirred at room temperature. To this, 0.58 part of a 28% methanol solution of sodium methoxide as a catalyst was added and stirred, and the temperature was raised to 70 °C and aged for 1 day. The reaction rate of 3-aminopropyltrimethoxysilane was 97%, and methanol almost equimolar to the reacted 3-aminopropyltrimethoxysilane was by-produced. Then, 1.1 parts of bis(2-ethylhexyl)phosphoric acid as an acidic compound was added, and then methanol and residual methyl acetate were removed by depressurization at 50 °C to 70 °C and concentrated. As a result, as an N-position acyl-modified intermediate, 222 parts of crude 3-acetamidopropyltrimethoxysilane containing catalyst-derived residues (in formula (7), R 2 is a methyl group, R 3 is a propylene group, R 7 is a methyl group, and n is 0 compound) were obtained. In another flask under a nitrogen atmosphere, 250 parts of mineral spirit, 204 parts of "Swazol 1000" (a naphtha-based solvent, trade name, manufactured by Maruzen Petrochemical Co., Ltd.), and 500 parts of "Duraneate TSA-100" were placed and stirred at room temperature. To this, 55 parts of crude 3-acetamidopropyltrimethoxysilane was added, and heated at 110 °C for 10 hours to adduct the secondary amide group to the isocyanate group, and a polyisocyanate hardener solution (HE-17) with a non-volatile content concentration of 55% was obtained. The concentration of the isocyanate group contained in the hardener solution (HE-17) was 2.14 mmol / g (3.89 mmol / g in terms of non-volatile content).

[0165] Example 18 89 parts of methyl acetate, which is a linear saturated ester, and 179 parts of 3-aminopropyltrimethoxysilane were placed in a flask under a nitrogen atmosphere and stirred at room temperature. To this, 0.58 part of a 28% methanol solution of sodium methoxide as a catalyst was added and stirred, and the temperature was raised to 70 °C and aged for 1 day. The reaction rate of 3-aminopropyltrimethoxysilane was 97%, and methanol almost equimolar to the reacted 3-aminopropyltrimethoxysilane was by-produced. Then, after adding 0.58 part of p-toluenesulfonic acid as an acidic compound, the pressure was reduced at 50 °C to 70 °C to remove methanol and residual methyl acetate and concentrate. As a result, as an N-position acyl-modified intermediate, crude 3-acetamidopropyltrimethoxysilane containing catalyst-derived residues (in formula (7), R 2 is a methyl group, R 3 is a propylene group, R 7 is a methyl group, and n is 0 compound) 222 parts were obtained. 62 parts of butyl acetate and 500 parts of "Durinate TSA-100" were placed in another flask under a nitrogen atmosphere and stirred at room temperature. To this, 55 parts of crude 3-acetamidopropyltrimethoxysilane was added, heated at 110 °C for 7 hours, and the secondary amide group was adducted to the isocyanate group to obtain a polyisocyanate curing agent solution (HE-18) with a non-volatile content concentration of 90%. The concentration of the isocyanate group contained in the curing agent solution (HE-18) was 3.49 mmol / g (3.88 mmol / g in terms of non-volatile content).

[0166] Example 19 In a flask under a nitrogen atmosphere, 89 parts of methyl acetate, which is a linear saturated ester, and 179 parts of 3-aminopropyltrimethoxysilane were placed and stirred at room temperature. 0.58 parts of a 28% methanol solution of sodium methoxide was added as a catalyst, and the mixture was stirred and heated to 70°C and aged for one day. The reaction rate of 3-aminopropyltrimethoxysilane was 97%, and methanol was by-produced in an amount approximately equal to the moles of the reacted 3-aminopropyltrimethoxysilane. After that, 1.1 parts of bis(2-ethylhexyl)phosphoric acid was added as an acidic compound, and the mixture was concentrated by removing methanol and remaining methyl acetate under reduced pressure at 50°C to 70°C. As a result, crude 3-acetamidopropyltrimethoxysilane (R 2 is a methyl group, R 3 is a propylene group, R 7 This yielded 222 parts of a compound in which n is a methyl group and n is 0. In a separate flask under a nitrogen atmosphere, 62 parts of butyl acetate and 500 parts of "Duranate TSA-100" were placed and stirred at room temperature. To this was added 55 parts of crude 3-acetamidopropyltrimethoxysilane, and the mixture was heated at 110°C for 7 hours to adduct the secondary amide groups to isocyanate groups, yielding a polyisocyanate hardener solution (HE-19) with a non-volatile content of 90%. The concentration of isocyanate groups in the hardener solution (HE-19) was 3.49 mmol / g (3.88 mmol / g in terms of non-volatile content).

[0167] Example 20 89 parts of methyl acetate, which is a linear saturated ester, and 179 parts of 3-aminopropyltrimethoxysilane were placed in a flask under a nitrogen atmosphere and stirred at room temperature. To this, 0.58 part of a 28% methanol solution of sodium methoxide was added as a catalyst, and the mixture was stirred and heated to 70 °C and aged for 1 day. The reaction rate of 3-aminopropyltrimethoxysilane was 97%, and methanol approximately equimolar to the reacted 3-aminopropyltrimethoxysilane was by-produced. Then, 1.03 parts of dodecylbenzenesulfonic acid was added as an acidic compound, and after depressurizing at 50 °C to 70 °C to remove methanol and residual methyl acetate and concentrating, as an N-position acyl-modified intermediate, crude 3-acetamidopropyltrimethoxysilane containing catalyst-derived residues (in formula (7), R 2 is a methyl group, R 3 is a propylene group, R 7 is a methyl group, and n is 0 compound) 222 parts were obtained. 62 parts of butyl acetate and 500 parts of "Duránate TSA-100" were placed in another flask under a nitrogen atmosphere and stirred at room temperature. To this, 55 parts of crude 3-acetamidopropyltrimethoxysilane was added, and the mixture was heated at 110 °C for 7 hours to adduct the secondary amide group to the isocyanate group, and a polyisocyanate curing agent solution (HE-20) with a non-volatile content concentration of 90% was obtained. The concentration of the isocyanate group contained in the curing agent solution (HE-20) was 3.49 mmol / g (3.88 mmol / g in terms of non-volatile content).

[0168] Example 21 190 parts of methyl octanoate, which is a linear saturated ester, and 179 parts of 3-aminopropyltrimethoxysilane were placed in a flask under a nitrogen atmosphere and stirred at room temperature. To this, 1.16 parts of a 28% methanol solution of sodium methoxide as a catalyst was added and stirred, and the temperature was raised to 70 °C and aged for 2 days. The reaction rate of 3-aminopropyltrimethoxysilane was 94%, and methanol almost equimolar to the reacted 3-aminopropyltrimethoxysilane was by-produced. Then, 2.2 parts of bis(2-ethylhexyl)phosphoric acid as an acidic compound was added, and after depressurizing at 50 °C to 70 °C to remove methanol and concentrate, as an N-position acyl-modified intermediate, crude 3-octanamidopropyltrimethoxysilane containing catalyst-derived residue (in formula (7), R 2 is a methyl group, R 3 is a propylene group, R 7 is a heptyl group, and n is 0 compound) 331 parts were obtained. 65 parts of butyl acetate and 500 parts of "Duránate TSA-100" were placed in another flask under a nitrogen atmosphere and stirred at room temperature. 82 parts of crude 3-octanamidopropyltrimethoxysilane was added thereto, heated at 110 °C for 12 hours to adduct the secondary amide group to the isocyanate group, cooled, and then filtered through filter paper to obtain a polyisocyanate curing agent solution (HE-21) with a non-volatile content concentration of 90%. The concentration of the isocyanate group contained in the curing agent solution (HE-21) was 3.18 mmol / g (3.53 mmol / g in terms of non-volatile content).

[0169] Example 22 In a flask under a nitrogen atmosphere, 106 parts of methyl propionate, which is a linear saturated ester, and 179 parts of 3-aminopropyltrimethoxysilane were placed and stirred at room temperature. 0.58 parts of a 28% methanol solution of sodium methoxide was added as a catalyst, and the mixture was stirred and heated to 70°C for aging for 2 days. The reaction rate of 3-aminopropyltrimethoxysilane was 97%, and methanol was by-produced in an amount approximately equal to the moles of the reacted 3-aminopropyltrimethoxysilane. After that, 1.1 parts of bis(2-ethylhexyl)phosphoric acid was added as an acidic compound, and the mixture was concentrated by removing methanol and remaining methyl propionate under reduced pressure at 50°C to 80°C. As a result, crude 3-propanamidylpropyltrimethoxysilane (R 2 is a methyl group, R 3 is a propylene group, R 7 In a separate flask under a nitrogen atmosphere, 60 parts of butyl acetate and 500 parts of "Duranate TSA-100" were placed and stirred at room temperature. To this was added 41 parts of crude 3-propanamidpropyltrimethoxysilane, and the mixture was heated at 110°C for 9 hours to adduct the secondary amide groups to isocyanate groups, yielding a polyisocyanate hardener solution (HE-22) with a non-volatile content of 90%. The concentration of isocyanate groups in the hardener solution (HE-22) was 3.67 mmol / g (4.08 mmol / g in terms of non-volatile content).

[0170] Example 23 96 parts of methyl acetate, which is a linear saturated ester, and 179 parts of 3-aminopropyltrimethoxysilane were placed in a flask under a nitrogen atmosphere and stirred at room temperature. To this, 0.58 part of a 28% methanol solution of sodium methoxide as a catalyst was added and stirred, and the temperature was raised to 70 °C and aged for 1 day. The reaction rate of 3-aminopropyltrimethoxysilane was 98%, and methanol almost equimolar to the reacted 3-aminopropyltrimethoxysilane was by-produced. Then, 1.1 parts of bis(2-ethylhexyl)phosphoric acid as an acidic compound was added, and then methanol and residual methyl acetate were removed by decompression at 50 °C to 70 °C and concentrated. Further, vacuum distillation was carried out at a vacuum degree of 4 mmHg to obtain 200 parts of purified 3-acetamidopropyltrimethoxysilane (in formula (7), R 2 is a methyl group, R 3 is a propylene group, R 7 is a methyl group, and n is 0 compound). 114 parts of propylene glycol monomethyl ether acetate and 500 parts of "Sumidule N-3300" (hexamethylene diisocyanate-based isocyanurate-type polyisocyanate, manufactured by Sumitomo Covestro Urethane Co., Ltd., trade name, isocyanate group content 21.8 wt%) were placed in another flask under a nitrogen atmosphere and stirred at room temperature. To this, 144 parts of purified 3-acetamidopropyltrimethoxysilane was added and heated at 110 °C for 9 hours to adduct the secondary amide group to the isocyanate group, and a polyisocyanate curing agent solution (HE-23) with a non-volatile content concentration of 85% was obtained. The concentration of the isocyanate group contained in the curing agent solution (HE-23) was 2.50 mmol / g (2.94 mmol / g in terms of non-volatile content).

[0171] Example 24 206 parts of methyl 3,3,5-trimethylhexanoate, which is a branched saturated ester having two hydrogen atoms at the α-position, and 179 parts of 3-aminopropyltrimethoxysilane were placed in a flask under a nitrogen atmosphere and stirred at room temperature. To this, 1.16 parts of a 28% methanol solution of sodium methoxide was added as a catalyst, stirred, heated to 70 °C and aged for 2 days. The reaction rate of 3-aminopropyltrimethoxysilane was 71%, and methanol almost equimolar to the reacted 3-aminopropyltrimethoxysilane was by-produced. Then, 2.2 parts of bis(2-ethylhexyl)phosphoric acid was added as an acidic compound, and then methanol was removed and concentrated under reduced pressure at 50 °C to 70 °C. Further, vacuum distillation was carried out at a vacuum of 4 mmHg to obtain 170 parts of purified 3-(3,3,5-trimethylhexanamide)propyltrimethoxysilane (in formula (7), R 2 is a methyl group, R 3 is a propylene group, R 7 is a 2,2,4-trimethylpentyl group, and n is 0 compound). 64 parts of butyl acetate and 500 parts of "Duránate TSA-100" were placed in another flask under a nitrogen atmosphere and stirred at room temperature. 79 parts of purified 3-(3,3,5-trimethylhexanamide)propyltrimethoxysilane was added thereto, heated at 110 °C for 9 hours, and the secondary amide group was adducted to an isocyanate group to obtain a polyisocyanate curing agent solution (HE-24) having a non-volatile content concentration of 90%. The concentration of the isocyanate group contained in the curing agent solution (HE-24) was 3.39 mmol / g (3.77 mmol / g in terms of non-volatile content).

[0172] Example 25 In the same manner as in Example 17 except that bis(2-ethylhexyl)phosphoric acid was not added, crude 3-acetamidopropyltrimethoxysilane (in formula (7), R 2 is a methyl group, R 3 is a propylene group, R 7222 parts of the compound where R is a methyl group and n is 0 were obtained. In another flask under a nitrogen atmosphere, 62 parts of propylene glycol monomethyl ether acetate and 500 parts of "Duronate TSA-100" were placed and stirred at room temperature. To this, 55 parts of crude 3-acetamidopropyltrimethoxysilane were added and heated at 110 °C for 7 hours to adduct the secondary amide group to the isocyanate group, obtaining a polyisocyanate curing agent solution (HE-25) with a non-volatile content concentration of 90%. The concentration of the isocyanate group contained in the curing agent solution (HE-25) was 3.13 mmol / g (3.48 mmol / g in terms of non-volatile content).

[0173] Example 26 In a flask under a nitrogen atmosphere, 206 parts of methyl 3,3,5-trimethylhexanoate, which is a branched saturated ester and has two hydrogen atoms at the α-position, and 179 parts of 3-aminopropyltrimethoxysilane were placed and stirred at room temperature. To this, 1.16 parts of a 28% methanol solution of sodium methoxide as a catalyst were added and stirred, and the temperature was raised to 70 °C and aged for 2 days. The reaction rate of 3-aminopropyltrimethoxysilane was 71%, and methanol almost equimolar to the reacted 3-aminopropyltrimethoxysilane was by-produced. Then, 2.2 parts of bis(2-ethylhexyl)phosphoric acid as an acidic compound were added, and then methanol was removed by distillation under reduced pressure at 50 °C to 70 °C and concentrated to obtain crude 3-(3,3,5-trimethylhexanamide)propyltrimethoxysilane containing catalyst-derived residues as an N-position acyl-modified intermediate (in formula (7), R 2 is a methyl group, R 3 is a propylene group, R 7365 parts of a compound in which R is a 2,2,4-trimethylpentyl group and n is 0 were obtained. Since this was not purified by distillation, a large amount of 3-aminopropyltrimethoxysilane derived from the raw material remained, and it was a mixture of 71 mol% of 3-(3,3,5-trimethylhexanamide)propyltrimethoxysilane and 29 mol% of 3-aminopropyltrimethoxysilane. 65 parts of propylene glycol monomethyl ether acetate and 500 parts of "Duronate TSA-100" were placed in another flask under a nitrogen atmosphere and stirred at room temperature. 90 parts of crude 3-(3,3,5-trimethylhexanamide)propyltrimethoxysilane was added thereto, and the mixture was heated at 110 °C for 7 hours to adduct the secondary amide group to the isocyanate group, obtaining a polyisocyanate curing agent solution (HE-26) with a nonvolatile content concentration of 90%. The concentration of the isocyanate group contained in the curing agent solution (HE-26) was 3.25 mmol / g (3.61 mmol / g in terms of nonvolatile content).

[0174] Comparative Example 9 56 parts of butyl acetate and 500 parts of "Duronate TSA-100" were placed in a flask under a nitrogen atmosphere and stirred at room temperature to obtain a polyisocyanate curing agent solution (HR-9) with a nonvolatile content concentration of 90%. The concentration of the isocyanate group contained in the curing agent solution (HR-9) was 4.46 mmol / g (4.96 mmol / g in terms of nonvolatile content).

[0175] Comparative Example 10 248 parts of mineral spirit, 198 parts of "Swazol 1000" (a naphtha-based solvent, trade name, manufactured by Maruzen Petrochemical Co., Ltd.), and 500 parts of "Duronate TSA-100" were placed in a flask under a nitrogen atmosphere and stirred at room temperature. When 44.3 parts of 3-aminopropyltrimethoxysilane was dropped therein, a curing agent solution (HR-10) was obtained, but since a gummy substance precipitated, the study was discontinued.

[0176]

Table 3

[0177] [Evaluation Items] (*) Generation of N-position acyl modified product The generation rates (%) of the N-position acyl modified products in Examples 17 to 26 were calculated and evaluated according to the following criteria. GOOD, FAIR, and POOR in the table have the following meanings. The larger the numerical value of the generation rate (%), the better. Good: 80% or more, Fair: 30% or more and less than 80%, Poor: Less than 30%.

[0178] (*) Ease of manufacture of intermediate containing N-position acyl modified product The ease of manufacture of the polyisocyanate curing agent solutions obtained in Examples 17 to 26 was evaluated according to the following criteria. AA and A were judged as qualified. In addition, Y described in the column of whether a distillation apparatus is applied means that a distillation apparatus is applied, and N means that no distillation apparatus is applied. AA: Can be manufactured without applying a distillation apparatus, A: Can be manufactured if a distillation apparatus is applied, B: Difficult to manufacture even if a distillation apparatus is applied because the generation rate of the N-position acyl modified product is low. (*) Isocyanate group stability at 20 °C The NCO residual rate after 3 months at 20 °C in the polyisocyanate curing agent solutions obtained in Examples 17 to 26 and Comparative Example 9 was measured by the same procedure as in Example 1 and evaluated according to the following criteria. The larger the numerical value of the residual rate (%), the better.

[0179] Good: 95% or more, Fair: 90% or more and less than 95%, Poor: Less than 90%.

[0180] [Manufacture of clear coating] Examples 27 to 57 and Comparative Examples 11 to 18 The main agent was manufactured with the compounding compositions described in Tables 4, 5, and 6 below, and the polyisocyanate curing agent solutions (HE-1) to (HE-26), (HR-1) to (HR-3), (HR-5) to (HR-7), (HR-9) after 3 days from the manufacture were mixed to obtain each clear coating (U-1) to (U-41). Similarly, old polyisocyanate curing agent solutions (HE-1) to (HE-7), (HR-3) that had been produced 12 months prior to being mixed with the main agents described in Table 4 were mixed to produce each clear coating (U'-1) to (U'-9), (U'-12). Also, old polyisocyanate curing agent solutions (HE-8) to (HE-16), (HR-5) to (HR-7) that had been produced 3 months prior to being mixed with the main agents described in Table 5 were mixed to produce each clear coating (U'-13) to (U'-26). Similarly, polyisocyanate curing agent solutions (HE-8) to (HE-16), (HR-7) that had been stored in a sealed container under low-temperature conditions of 5°C for 2 weeks after being produced and then mixed with the main agents described in Table 5 were mixed to produce each clear coating (U''-13) to (U''-23), (U''-26). Similarly, old polyisocyanate curing agent solutions (HE-17) to (HE-26), (HR-9) that had been produced 3 months prior to being mixed with the main agents described in Table 6 were mixed to produce each clear coating (U'-27) to (U'-41).

[0181] Note that the numerical values in Tables 4, 5, and 6 are the total mass including volatile components, not the mass of the non-volatile components.

[0182]

Table 4

[0183]

Table 5

[0184]

Table 6

[0185] (Note 4) Polyol Solution 1: Styrene / i-butyl methacrylate / 2-ethylhexyl acrylate / hydroxyethyl methacrylate = 30 / 30 / 30 / 10 copolymer solution, weight average molecular weight 20,000, hydroxyl value per non-volatile content 43 mg KOH / g, non-volatile content concentration 50%, solvent: mineral spirit / 「Swazol 1000」 mass ratio = 1 / 1 (Note 5) Polyol Solution 2: Styrene / i-butyl methacrylate / 2-ethylhexyl acrylate / hydroxyethyl methacrylate / acrylic acid = 30 / 35 / 29 / 5 / 1 copolymer solution, weight average molecular weight 20,000, hydroxyl value per non-volatile content 22 mg KOH / g, non-volatile content concentration 50%, solvent: mineral spirit / 「Swazol 1000」 mass ratio = 1 / 1 (Note 6) Aspartic acid ester 1: Desmophen NH1523LF manufactured by Covestro (N,N‘-(methylenebis(2-methyl-di-4,1-cyclohexanediyl))-bisaspartic acid tetraethyl, content > 99%, amine value 200 mg KOH / g) (Note 7) Neo-Stan U-830: Trade name, manufactured by Nitto Kasei Co., Ltd., dioctyltin compound (Note 8) Aspartic acid ester 2: Desmophen NH1423LF manufactured by Covestro (N,N‘-(methylenebis(di-4,1-cyclohexanediyl))-bisaspartic acid tetraethyl, content > 99%, amine value 205 mg KOH / g).

[0186] [Performance Evaluation] For each clear coating obtained in the above examples and comparative examples, the following performance evaluation tests were carried out. In this test, coating was performed immediately after mixing the main agent and the curing agent. (*) Curing property On the glass plate, each clear coating was drawn and applied using a 200 μm applicator, and the coating film obtained by drying for 7 days in a chamber at room temperature of 23 °C and humidity of 50% was peeled off from the glass plate. This coating film was wrapped with a 200-mesh stainless steel wire mesh, immersed in a mixed solution of acetone / methanol with a mass ratio of 1 / 1 for 24 hours, then the wire mesh wrapped with the coating film was taken out and dried at 100 °C for 1 hour, and the insoluble matter fraction was measured from the mass of the coating film remaining on the wire mesh. ◎ and 〇 ranks were judged as qualified, and △ and × ranks were judged as unqualified. ◎: Insoluble matter fraction 85% or more 〇: Insoluble matter fraction 70% or more and less than 85% △: Insoluble matter fraction 55% or more and less than 70% ×: Insoluble matter fraction less than 55%. (*) Adhesion As substrates, two types of metal plates were prepared (ferrous metal: a degreased metal plate of SPCC-SD (cold-rolled steel sheet dull finish), non-ferrous metal: an aluminum plate of 5052P sanded with 240 grit (3.2 mm × 70 mm × 150 mm)). On each metal plate, each clear coating was drawn and applied using a 200 μm applicator, and dried in a chamber at room temperature of 23 °C and humidity of 50% for 7 days to obtain each test coated plate. Using a cutter, 100 squares with a width of 2 mm were cut in a grid pattern on the coating film, and after attaching an adhesive tape and peeling it off, a peeling test was performed 3 times, and the number of squares that did not peel off was measured. ◎ and 〇 ranks were judged as qualified, and △ and × ranks were judged as unqualified. ◎: 100 squares 〇: 75 squares or more and 99 or less △: 51 squares or more and 74 squares or less ×: 50 squares or less (*) Water resistance adhesion Similar to the metal plates used in the above adhesion test, two types of metal plates of iron and aluminum were prepared. On each metal plate, each clear coating was drawn and applied using a 200 μm applicator, and dried in a chamber at room temperature of 23 °C and humidity of 50% for 7 days to obtain each test coated plate. Each test coated panel was immersed in warm water at 40°C for 3 days, then in water at 20°C for 1 hour, and then taken out. The water on the coating surface of the test coated panel was wiped off, and immediately, using a cutter, 100 squares in a 10×10 grid pattern with a width of 2 mm were cut from the coating film. After attaching an adhesive tape and peeling it off, a peeling test was performed 3 times, and the number of squares that did not peel off was measured. Ranks ◎ and 〇 were judged as passing, while ranks △ and × were judged as failing. ◎: 100 squares 〇: 75 or more and 99 or less squares △: 51 or more and 74 or less squares ×: 50 or less squares.

[0187] [Manufacture of 1 - coat coating] Examples 60 - 92 and Comparative Examples 19 - 26 The main agent was manufactured with the formulation compositions described in Tables 7, 8, and 9 below. After 3 days from the manufacture, polyisocyanate curing agent solutions (HE - 1) - (HE - 26), (HR - 1) - (HR - 3), (HR - 5) - (HR - 7), (HR - 9) were mixed to obtain each 1 - coat coating (U - 42) - (U - 82). Also, similarly, old polyisocyanate curing agent solutions (HE - 1) - (HE - 7), (HR - 3) that had passed 12 months from the manufacture were mixed with the main agent described in Table 7 to manufacture each 1 - coat coating (U' - 42) - (U' - 50) and (U' - 53). Also, old polyisocyanate curing agent solutions (HE - 8) - (HE - 16), (HR - 5) - (HR - 7) that had passed 3 months from the manufacture were mixed with the main agent described in Table 8 to manufacture each 1 - coat coating (U' - 54) - (U' - 67). Similarly, polyisocyanate curing agent solutions (HE - 8) - (HE - 16), (HR - 7) that had been stored under sealed conditions for 2 weeks at 5°C after 3 months from the manufacture were mixed with the main agent described in Table 8 to manufacture each 1 - coat coating (U'' - 54) - (U'' - 64), (U'' - 67). Similarly, old polyisocyanate curing agent solutions (HE-17) to (HE-26), (HR-9) that had been produced 3 months prior were mixed with the main agents described in Table 9, and each one-coat coating (U'-68) to (U'-82) was produced.

[0188] Note that the numerical values in Tables 7, 8, and 9 are the total mass including volatile components, not the mass of non-volatile components.

[0189]

Table 7

[0190]

Table 8

[0191]

Table 9

[0192] (Note 9) Rust preventive pigment composition: Magnesium phosphate / "Silica 710" (silica, manufactured by Fuji Silysia Chemical, trade name) / Calcium silicate = 50 / 30 / 20 mixture and modified product.

[0193] [Performance Evaluation] (*) Curing property: It was carried out in the same manner as the curing property test conducted with the above clear coating and evaluated according to the same criteria. (*) Corrosion resistance: On a zinc phosphate-treated SPCC steel sheet (size 3.2 mm × 70 mm × 150 mm), each one-coat coating within 30 minutes after mixing the main agent and the curing agent was brush-coated at an application rate of 100 g / m 2 and cured at 20°C for 7 days. After that, a cut 8 cm long was made with a cutter until it reached the substrate, and the resulting test coated plate was used as a test specimen. The obtained test coated plate was tested in a 5% salt water spray test apparatus at a temperature of 35°C for 240 hours, and then evaluated in four grades by observing the appearance of the test plate. ◎: The maximum value of the rust width (one side) progressing from the cut part is less than 15 mm, and there is no abnormality in the general part. ○: The maximum value of the rust width (one side) progressing from the cut part is 15 or more and less than 20 mm, and there is no abnormality in the general part. △: The maximum value of the rust width progressing from the cut part (one side) is less than 20 mm, but there are bulges and rust in the general part. ×: The maximum value of the rust width progressing from the cut part (one side) exceeds 20 mm, and there are bulges and rust in the general part. (*) Weather resistance On the zinc phosphate-treated SPCC steel sheet, the main agent and the curing agent were mixed and each coat coating within 30 minutes was applied at a coating amount of 100 g / m 2 and brush-coated, and cured at 20 °C for 7 days to obtain a test coated plate. This test coated plate was irradiated for 300 hours according to the accelerated weather resistance test of JIS K 5600's 7-7 (xenon lamp method), and then the test coated plate was evaluated according to the following criteria. ◎: No change in gloss is observed compared to the initial stage. ○: A change in gloss is observed compared to the initial stage, but at an unobtrusive level. △: A change in gloss is clearly observed compared to the initial stage. ×: The change in gloss is significant compared to the initial stage.

Claims

1. A modified polyisocyanate for use together with an active hydrogen-containing compound as a curing agent for a coating, which is a reaction product obtained from components including an alkoxysilane (a1) having a primary amino group, an unsaturated carboxylic acid alkyl ester (a2) or a saturated carboxylic acid alkyl ester (a3), and a polyisocyanate (a4), wherein the unsaturated carboxylic acid alkyl ester (a2) is a branched alkyl ester of an unsaturated dicarboxylic acid (a2-1), and a branched alkyl ester optionally containing a hetero atom of an unsaturated monocarboxylic acid or an alkyl ester having a cyclic structure (a2-2) and is at least one selected from the group consisting of: the modified polyisocyanate.

2. The modified polyisocyanate according to claim 1, wherein the alkoxysilane (a1) having a primary amino group is a compound represented by the following formula (1). 【Chemical Formula 1】 In formula (1), R １ and R ２ are the same or different and are a linear or branched alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, alkynyl group, cycloalkynyl group, aryl group or heteroaryl group having 1 to 18 carbon atoms which may be substituted, and R 3 is a linear or branched alkylene group having 1 to 8 carbon atoms, and n is an integer of 0 to 2.

3. The modified polyisocyanate according to claim 1, wherein the branched alkyl ester of the unsaturated dicarboxylic acid (a2-1) is a compound represented by the following formula (2). R ４ O−C(=O)−HC=CH−C(=O)−OR ５ (2) In formula (2), R ４ and R ５ are the same or different and are branched alkyl groups having 1 to 8 carbon atoms.

4. The modified polyisocyanate according to claim 1, wherein the branched alkyl ester optionally containing a hetero atom of an unsaturated monocarboxylic acid or an alkyl ester having a cyclic structure (a2-2) is a compound represented by the following formula (3). H ２ C═CH−C(═O)−OR ６ (3) In formula (3), R ６ represents a branched alkyl group having 3 to 18 carbon atoms or an alkyl group having a cyclic structure, or a group formed by incorporating a heteroatom into a molecule of a branched or cyclic alkyl group or arylalkyl group having 1 to 18 carbon atoms.

5. The modified polyisocyanate according to claim 1, wherein the saturated carboxylic acid alkyl ester (a3) is a compound represented by the following formula (4). R ７ -C(=O)-OR ８ (4) In formula (4), R ７ and R ８ are the same or different and each represents an alkyl group having 1 to 18 carbon atoms and not having an unsaturated group, or a group having 1 to 18 carbon atoms and obtained by incorporating a hetero atom into the molecule of the alkyl group and not having an unsaturated group.

6. The modified polyisocyanate according to claim 1, having a structure in which the secondary amino group of an alkoxysilane N-position modified product formed by the addition of the primary amino group of the alkoxysilane (a1) to the unsaturated carbon-carbon bond of the unsaturated carboxylic acid alkyl ester (a2) is added to the isocyanate group of the polyisocyanate (a4).

7. The modified polyisocyanate according to claim 1, having a structure in which the secondary amide group of an alkoxysilane N-position modified product formed by the reaction of the primary amino group of the alkoxysilane (a1) with the ester group of the saturated carboxylic acid alkyl ester (a3) is added to the isocyanate group of the polyisocyanate (a4).

8. The unsaturated carboxylic acid alkyl ester (a2) is a branched alkyl ester (a2-1) of an unsaturated dicarboxylic acid, and the alkoxysilane N-position modified product is a compound represented by the following formula (5). The modified polyisocyanate according to claim 6. 【Chemical 2】 In formula (5), R １ and R ２ are the same or different and are a linear or branched alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, alkynyl group, cycloalkynyl group, aryl group or heteroaryl group having 1 to 18 carbon atoms, which may be substituted; R 3 is a linear or branched alkylene group having 1 to 8 carbon atoms; R ４ and R ５ are the same or different and are branched alkyl groups having 1 to 8 carbon atoms; and n is an integer from 0 to 2.

9. The reaction ratio of the alkoxysilane N-position modified product having a secondary amino group and the polyisocyanate (a4) is such that the number of moles of the secondary amino group is 40 moles or less per 100 moles of isocyanate groups. The modified polyisocyanate according to claim 7.

10. The unsaturated carboxylic acid alkyl ester (a2) is a branched alkyl ester optionally containing a heteroatom of an unsaturated monocarboxylic acid or an alkyl ester having a cyclic structure (a2-2), and the alkoxysilane N-position modified product is a compound represented by the following formula (6). The modified polyisocyanate according to claim 6. [Chemical Formula 3] In formula (6), R １ and R ２ are the same or different and are a linear or branched alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, alkynyl group, cycloalkynyl group, aryl group or heteroaryl group having 1 to 18 carbon atoms, which may be substituted; R 3 is a linear or branched alkylene group having 1 to 8 carbon atoms; R ６ is an alkyl group having a branched or cyclic structure and having 1 to 18 carbon atoms, or a group formed by including a heteroatom in a molecule of an alkyl group or arylalkyl group having a branched or cyclic structure and having 1 to 18 carbon atoms; n is an integer of 0 to 2.

11. The reaction ratio of the mixture containing the alkoxysilane N-position modified product having a secondary amino group and the polyisocyanate (a4) is such that the total number of moles of the primary amino group and the secondary amino group is 40 moles or less per 100 moles of isocyanate groups. The modified polyisocyanate according to claim 8.

12. The alkoxysilane N-position modified product obtained by reacting an alkoxysilane (a1) with a saturated carboxylic acid alkyl ester (a3) is an N-position acyl modified product represented by the following formula (7) having a secondary amide group. The modified polyisocyanate according to claim 7. 【Chemical 4】 In formula (7), R １ and R ２ are the same or different and are a linear or branched alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, alkynyl group, cycloalkynyl group, aryl group or heteroaryl group having 1 to 18 carbon atoms, which may be substituted; R 3 is a linear or branched alkylene group having 1 to 8 carbon atoms, n is an integer of 0 to 2, and R ７ represents an alkyl group having 1 to 18 carbon atoms and no unsaturated group, or a group formed by incorporating a heteroatom into a molecule of an alkyl group or arylalkyl group having 1 to 18 carbon atoms and having no unsaturated group.

13. Step (1) of reacting an alkoxysilane (a1) having a primary amino group and a saturated carboxylic acid alkyl ester (a3) in the presence of a basic catalyst, Step (2) of adding an acidic compound, Step (3) of removing part or all of the alcohol produced as a by-product to prepare an intermediate containing an N-position acyl modified product represented by the following formula (7), Step (4) of reacting the intermediate with a polyisocyanate (a4) The modified polyisocyanate according to claim 1, which is produced by 【Chemical Formula 5】 In formula (7), R １ and R ２ are the same or different and are a linear or branched alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, alkynyl group, cycloalkynyl group, aryl group or heteroaryl group having 1 to 18 carbon atoms which may be substituted, R 3 is a linear or branched alkylene group having 1 to 8 carbon atoms, n is an integer of 0 to 2, and R ７ represents an alkyl group having 1 to 18 carbon atoms and having no unsaturated group, or a group having 1 to 18 carbon atoms and containing a hetero atom in the molecule of the alkyl group and having no unsaturated group.

14. The reaction ratio of the N-position acyl modified product and the polyisocyanate (a4) is such that the total number of moles of the secondary amide group and the primary amino group is 40 moles or less per 100 moles of isocyanate groups. The modified polyisocyanate according to claim 12.

15. Step (1) of reacting an alkoxysilane (a1) having a primary amino group and an alkyl saturated carboxylate (a3) in the presence of a basic catalyst; Step (2) of adding an acidic compound; Step (3) of removing some or all of the alcohol produced as a by-product to prepare an intermediate containing an N-acyl modified product represented by the following formula (7); Step (4) of reacting the intermediate with a polyisocyanate (a4) The method for producing a modified polyisocyanate according to claim 1, comprising: ​ In formula (7), R １ and R ２ are the same or different and are a linear or branched alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, alkynyl group, cycloalkynyl group, aryl group or heteroaryl group having 1 to 18 carbon atoms which may be substituted, R 3 is a linear or branched alkylene group having 1 to 8 carbon atoms, n is an integer of 0 to 2, and R ７ represents an alkyl group having 1 to 18 carbon atoms and no unsaturated group, or a group having 1 to 18 carbon atoms and containing a heteroatom in the molecule of the alkyl group and having no unsaturated group.

16. The unsaturated carboxylic acid alkyl ester (a2) is a branched alkyl ester which may contain a hetero atom of an unsaturated monocarboxylic acid or an alkyl ester having a cyclic structure (a2-2), and the reaction of the alkoxysilane N-position modified product having a secondary amino group with a polyisocyanate (a4) is carried out in the co-presence of an alkoxysilane (a1) having a primary amino group and a tertiary amino group-containing compound represented by the following formula (8) which is a by-product. The modified polyisocyanate according to claim 6. 【Chemical Formula 7】 In formula (8), R １ and R ２ are the same or different and are a linear or branched alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, alkynyl group, cycloalkynyl group, aryl group or heteroaryl group having 1 to 18 carbon atoms, which may be substituted; R 3 is a linear or branched alkylene group having 1 to 8 carbon atoms; R ６ is an alkyl group having a branched or cyclic structure with 1 to 18 carbon atoms, or a group formed by incorporating a heteroatom into a molecule of an alkyl group or arylalkyl group having a branched or cyclic structure with 1 to 18 carbon atoms; and n is an integer of 0 to 2.

17. The alkyl saturated carboxylate (a3) is an alkyl ester of a carboxylic acid having a linear structure and having two or more hydrogen atoms at the α-position, or an alkyl ester of a carboxylic acid having a branched structure and having two hydrogen atoms at the α-position. The modified polyisocyanate according to claim 1.

18. The method for producing a modified polyisocyanate according to claim 15, wherein the alkyl saturated carboxylate (a3) is an alkyl ester of a carboxylic acid having a linear structure and having two or more hydrogen atoms at the α-position.

19. A coating comprising an active hydrogen-containing compound and the modified polyisocyanate according to any one of claims 1 to 17.

20. The coating according to claim 19, wherein the active hydrogen-containing compound comprises an acrylic polyol and / or a bisaspartic acid ester derivative.

21. The coating according to claim 19, further comprising at least one selected from the group consisting of a rust inhibitor, a catalyst, a coloring pigment, and a extender pigment.

22. The coating according to claim 19, which is a one-coat paint.

23. A protective coating film formed by curing the coating according to claim 19.

24. A coated metal material in which the protective coating film according to claim 19 is formed on a metal substrate.

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