Method for manufacturing primer composition and primer composition

Abstract

To provide a method for manufacturing a primer composition that exhibits not only good adhesion after an applied (a coated and cured) area is immersed in water, but also good adhesion even when used (applied) to a wet surface.SOLUTION: There is provided a method for manufacturing a primer composition including the steps of: [i] mixing (A) a hydrolyzable aminoalkyl silane and / or its polycondensate, (B) a bifunctional epoxy monomer and / or its polymer, (C) a hydrolyzable organosilane compound other than (A) component and / or its partial hydrolysis condensate, and a part or all of (D) a non-alcoholic organic solvent, under reflux stirring with moisture blocked at a specified temperature to prepare a homogeneous reaction mixture; and [ii] adding the remaining (D) component and (E) an alkoxysilyl group-containing (meth)acrylate copolymer to the reaction mixture prepared in step [i] under moisture-blocking conditions and mixing them at 20 to 60°C to prepare a homogeneous composition.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a method for producing a primer composition and a primer composition that are useful for bonding a cured product of a room-temperature-curable organopolysiloxane composition to various adherends, and in particular to a primer composition and a method for producing the same that are characterized in that the area where they are applied (coated and cured) to an adherend exhibits good adhesion even after being immersed in water, and that they exhibit good adhesion even when used (applied) to the surface of an adherend in a wet state. [Background technology]

[0002] Room temperature curable organopolysiloxane compositions that crosslink and cure with atmospheric moisture (water) to become silicone elastomers are easy to handle, and the cured products (silicone rubber) have excellent weather resistance and electrical properties, so they are used in a variety of fields, such as sealing materials for building materials and adhesives in the electrical and electronic fields. In general, in order to adhere these room temperature curable organopolysiloxane compositions to various adherends, a method is used in which a primer composition is applied to the adherend in advance.

[0003] As primers, carbon functional silanes, such as aminoalkylsilanes, having functional groups capable of reacting with one component of room temperature curing organopolysiloxane compositions are known, but these have the drawback that when moisture is present at the application (construction) site, the adhesive strength decreases and in some cases peeling occurs. In addition, when these primers are used around concrete, which is the adherend, the migration of alkaline components contained in the concrete causes a decrease in adhesiveness and peeling is likely to occur. Furthermore, since it is expected to be used outdoors, it is possible that it will be affected by rainwater, and it is necessary for the application (applied and cured) site to have sufficient adhesiveness even after being immersed in water (submerged).

[0004] In this regard, Japanese Patent Laid-Open Publication No. 11-209682 (Patent Document 1) describes that the use of a composition made of an acrylic copolymer results in a high adhesive strength to concrete.

[0005] Furthermore, Japanese Patent Application Laid-Open No. 48-75633 (Patent Document 2) describes how reacting an aminoalkylalkoxysilane with an epoxyalkylalkoxysilane under specified conditions to produce an adhesion promoter maintains adhesive strength even after the application (coating and curing) area is immersed (submerged) in water.

[0006] However, when considering application (coating and curing) outdoors without a roof, not only is there the possibility of getting wet from rainwater or being submerged (submerged) after application (coating and curing), but the concrete surface of the adherend may also be wet during application. Since it is time-consuming to dry the adherend surface before each application, there is a demand for the development of a primer composition that can be used on a wet adherend surface (hereinafter also referred to as a wet surface) (i.e., that exhibits good adhesion even when applied to a wet surface). [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 11-209682 [Patent Document 2] Japanese Patent Application Publication No. 48-75633 Summary of the Invention [Problem to be solved by the invention]

[0008] The present invention has been made in consideration of the above circumstances, and has an object to provide a method for producing a primer composition and a primer composition which not only exhibits good adhesion to the applied (coated and cured) site even after immersion in water, but also exhibits good adhesion when used (applied) on a wet surface. [Means for solving the problem]

[0009] The present inventors have conducted intensive research to solve the above-mentioned problems, and as a result, have found that a reaction mixture of an aminoalkylsilane and / or a condensation polymer thereof, a bifunctional epoxy monomer and / or a polymer thereof, a hydrolyzable organosilane compound, and a non-alcoholic organic solvent is effective for improving the adhesion of a primer composition to wet surfaces and for improving the adhesion of the application (coating and curing) site after immersion in water, and further found that combining this reaction mixture with a (meth)acrylic copolymer having an alkoxysilyl group is extremely effective, thereby completing the present invention.

[0010] That is, the present invention provides the following method for producing a primer composition and the following primer composition. [1] (A) a hydrolyzable aminoalkylsilane and / or a condensation polymer thereof, (B) a difunctional epoxy monomer and / or a polymer thereof, (C) a hydrolyzable organosilane compound other than the component (A) and / or a partial hydrolysis condensate thereof, (D) non-alcoholic organic solvents, and (E) (Meth)acrylic copolymer having an alkoxysilyl group A method for producing a primer composition comprising: [i] a step of mixing all or part of the components (A), (B), (C), and (D) under reflux stirring at 20 to 150°C for 6 to 120 hours in a moisture-free environment to prepare a homogeneous reaction mixture; and [ii] a step of adding the remainder of component (D) and component (E) to the reaction mixture prepared in step [i] under moisture-blocking conditions, and mixing at 20 to 60°C to prepare a homogeneous composition; A method for producing a primer composition comprising the steps of: [2] The method for producing a primer composition according to [1], wherein the (meth)acrylic copolymer of the component (E) is a copolymer of a (meth)acrylic acid ester monomer having an alkoxysilyl group and a (meth)acrylic acid ester monomer not having an alkoxysilyl group. [3] The method for producing a primer composition according to [1] or [2], wherein the hydrolyzable aminoalkylsilane constituting component (A) is a silane compound represented by the following formula (1): R 1 R 2 a Six (3-a) (1) (In the formula, R 1 is an alkyl group having 1 to 10 carbon atoms substituted with a primary amino group and / or a secondary amino group, R 2 is a monovalent hydrocarbon group having 1 to 10 carbon atoms, X is a hydrolyzable group, and a is 0 or 1. [4] The method for producing a primer composition according to any one of [1] to [3], wherein the molar ratio of the epoxy groups contained in component (B) to the primary amino groups contained in component (A) is 2 to 20, and the molar ratio of the hydrolyzable groups in the hydrolyzable organosilane compound and / or its partial hydrolyzed condensate, component (C), to the primary amino groups contained in component (A) is 2 to 20. [5] The method for producing a primer composition according to any one of [1] to [4], wherein the molar ratio of the epoxy groups contained in component (B) to the secondary amino groups contained in component (A) is 1 to 10, and the molar ratio of the hydrolyzable groups in the hydrolyzable organosilane compound and / or its partial hydrolyzed condensate, component (C), to the secondary amino groups contained in component (A) is 1 to 10. [6] The method for producing a primer composition according to any one of [1] to [5], comprising 5 to 1,000 parts by mass of the (D) component and 2 to 100 parts by mass of the (E) component relative to a total of 10 parts by mass of the (A) component, the (B) component, and the (C) component. [7] (A) a hydrolyzable aminoalkylsilane and / or a condensation polymer thereof, (B) a difunctional epoxy monomer and / or a polymer thereof, (C) a hydrolyzable organosilane compound other than the component (A) and / or a partial hydrolysis condensate thereof, (D) non-alcoholic organic solvents, and (E) (Meth)acrylic copolymer having an alkoxysilyl group A primer composition comprising: A primer composition comprising all or part of the above components (A), (B), (C) and (D) as a heat-reaction mixture thereof. [8] The primer composition according to [7], wherein the heated reaction mixture is a 60 to 150°C heated reaction mixture of all or some of the components (A), (B), (C), and (D). [9] The primer composition according to [7] or [8], which is for adhesion to wet surfaces. Effect of the Invention

[0011] According to the manufacturing method of the present invention, the obtained primer composition is applied, that is, the surface of the adherend such as concrete is treated with a primer, and then the room temperature curable organopolysiloxane composition is applied and the film is cured, so that the applied (applied and cured) area shows good adhesion even after immersion in water. In addition, even if the surface of the adherend such as concrete is wet, the composition can be applied (applied and cured) without drying the wet surface, and still maintain good adhesion to the adherend. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] The present invention will be described in detail below, but the present invention is not limited thereto.

[0013] [Method of manufacturing primer composition] The method for producing the primer composition according to the present invention comprises the steps of: (A) a hydrolyzable aminoalkylsilane and / or a condensation polymer thereof, (B) a difunctional epoxy monomer and / or a polymer thereof, (C) a hydrolyzable organosilane compound other than the component (A) and / or a partial hydrolysis condensate thereof, (D) non-alcoholic organic solvents, and (E) (Meth)acrylic copolymer having an alkoxysilyl group A method for producing a primer composition comprising: [i] a step of mixing all or part of the components (A), (B), (C), and (D) under reflux stirring at 20 to 150°C for 6 to 120 hours in a moisture-free environment to prepare a homogeneous reaction mixture; and [ii] A step of adding the remainder of component (D) and component (E) to the reaction mixture prepared in step [i] under moisture protection, and mixing at 20 to 60°C to prepare a homogeneous composition. The present invention is characterized in that it comprises:

[0014] -(A) Component- Component (A) is a hydrolyzable aminoalkylsilane and / or a condensation polymer thereof, which reacts with components (B) and (C) described below to form a reaction mixture containing a part or all of component (D), thereby functioning as a film-forming component and an adhesive component.

[0015] The hydrolyzable aminoalkylsilane constituting component (A) is preferably a silane compound represented by the following formula (1). R 1 R 2 a Six (3-a) (1) (In the formula, R 1 is an alkyl group having 1 to 10 carbon atoms substituted with a primary amino group and / or a secondary amino group (aminoalkyl group), R 2 is a monovalent hydrocarbon group having 1 to 10 carbon atoms, X is a hydrolyzable group, and a is 0 or 1.

[0016] Here, R 1 is an alkyl group having 1 to 10 carbon atoms substituted with a primary amino group and / or a secondary amino group (aminoalkyl group), and NH2(CH2) n -, NHR 1 '(CH2) n -, NH2(CH2) n1 NH(CH2) n2 - or NHR 1 '(CH2) n1 NH(CH2) n2 - (n is an integer from 1 to 5, R1 ' is an alkyl group having 1 to 3 carbon atoms, and n1 and n2 are each an integer of 1 to 3.) is preferable.

[0017] R 2 is a monovalent hydrocarbon group having 1 to 10 carbon atoms, and examples thereof include alkyl groups having 1 to 10 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl, hexyl, heptyl, octyl, nonyl, and decyl; alkenyl groups having 2 to 10 carbon atoms, such as vinyl and allyl; aryl groups having 6 to 10 carbon atoms, such as phenyl and tolyl; and aralkyl groups having 7 to 10 carbon atoms, such as benzyl, and of these, methyl is preferred.

[0018] X is a hydrolyzable group, and examples thereof include alkoxy groups having 1 to 10 carbon atoms, such as a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, and a butoxy group; alkoxyalkoxy groups having 2 to 10 carbon atoms, such as a methoxymethoxy group, and a methoxyethoxy group; acyloxy groups having 2 to 10 carbon atoms, such as an acetoxy group, an octanoyloxy group, and a benzoyloxy group; alkenyloxy groups having 2 to 4 carbon atoms, such as a vinyloxy group, an allyloxy group, a propenoxy group, and an isopropenoxy group; and halogen groups, such as a chlorine group, a bromo group, and an iodo group. Of these, a methoxy group and an ethoxy group are preferable.

[0019] Examples of hydrolyzable aminoalkylsilanes constituting the component (A) include hydrolyzable organosilane compounds having an alkyl group substituted with a primary amino group and / or a secondary amino group in the molecule, and two or three hydrolyzable groups such as alkoxy groups bonded to silicon atoms in the molecule, such as γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, 3-2-(aminoethylamino)propyltrimethoxysilane, and / or their condensation polymers (organosiloxane oligomers having an alkyl group substituted with a primary amino group and / or a secondary amino group in the molecule and hydrolyzable groups such as residual alkoxy groups). In particular, when the compound has a primary amino group and a methoxy group, excellent film formation and adhesion are observed, and γ-aminopropyltrimethoxysilane, 3-2-(aminoethylamino)propyltrimethoxysilane, etc. are preferred. These may be used alone or in combination of two or more.

[0020] -(B) Component- Component (B) is a bifunctional epoxy monomer (a monomer having two epoxy groups in the molecule) and / or a polymer thereof, which reacts with component (A) and component (C) described below to form a reaction mixture containing part or all of component (D), thereby functioning as a film-forming component and an adhesive component.

[0021] The difunctional epoxy monomer constituting component (B) is a difunctional monomer having two epoxy groups in the molecule and containing no reactive functional groups other than the epoxy groups, and is preferably one containing two glycidyl ether groups and / or alicyclic epoxy groups, and more preferably an aliphatic epoxy compound containing two glycidyl ether groups.

[0022] Examples of the difunctional epoxy monomer constituting the component (B) include 1,2-cyclohexanedicarboxylate diglycidyl, neopentyl glycol diglycidyl ether, bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, bisphenol AF diglycidyl ether, etc. From the viewpoints of cost and solubility in solvents, bisphenol A diglycidyl ether is preferred. These may be used alone or in combination of two or more.

[0023] -(C) Component- Component (C) is a hydrolyzable organosilane compound other than component (A) and / or a partial hydrolyzed condensate thereof, which reacts with components (A) and (B) to form a reaction mixture containing part or all of component (D), thereby functioning as a regulator to prevent thickening over time of the film-forming components and the primer composition, and is preferably a hydrolyzable organosilane compound having three or more (particularly three or four) hydrolyzable groups bonded to silicon atoms in the molecule and / or a partial hydrolyzed condensate thereof (organosiloxane oligomer having residual hydrolyzable groups).

[0024] Examples of the hydrolyzable group bonded to a silicon atom in the hydrolyzable organosilane compound and / or partial hydrolysis condensate thereof constituting component (C) include ketoxime groups having 3 to 7 carbon atoms, such as a dimethylketoxime group, a methylethylketoxime group, or a diethylketoxime group; alkoxy groups having 1 to 10 carbon atoms, such as a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, or a butoxy group; acyloxy groups having 2 to 10 carbon atoms, such as an acetoxy group, an octanoyloxy group, or a benzoyloxy group; and alkenyloxy groups having 2 to 4 carbon atoms, such as a vinyloxy group, an allyloxy group, a propenoxy group, or an isopropenoxy group. Of these, alkoxy groups having 1 to 4 carbon atoms, ketoxime groups, and isopropenoxy groups are preferred.

[0025] Examples of organo groups (monovalent hydrocarbon groups) bonded to silicon atoms other than the hydrolyzable groups contained in the hydrolyzable organosilane compound and / or its partial hydrolysis condensate include alkyl groups having 1 to 10 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl, hexyl, heptyl, octyl, nonyl, and decyl; alkenyl groups having 2 to 10 carbon atoms, such as vinyl and allyl; and aryl groups having 6 to 10 carbon atoms, such as phenyl and tolyl, with alkyl groups having 1 to 4 carbon atoms being preferred. In the hydrolyzable organosilane compound and / or its partial hydrolysis condensate of component (C), it is preferred that the organo groups (monovalent hydrocarbon groups) bonded to silicon atoms other than the hydrolyzable groups do not have functional groups having heteroatoms, such as nitrogen, sulfur, and oxygen atoms.

[0026] Specific examples of the (C) component include ketoxime group-containing silanes such as methyltris(methylethylketoxime)silane, vinyltris(methylethylketoxime)silane, phenyltris(methylethylketoxime)silane, and methyltris(dimethylketoxime)silane; alkoxysilanes such as methyltrimethoxysilane, octyltrimethoxysilane, dimethyldimethoxysilane, vinyltrimethoxysilane, phenyltrimethoxysilane, methyltriethoxysilane, and α-(dimethoxymethylsilyl)propionate 2-ethylhexyl; isopropenoxy group-containing silanes such as methyltriisopropenoxysilane, ethyltriisopropenoxysilane, vinyltriisopropenoxysilane, and phenyltriisopropenoxysilane; acetoxysilanes such as methyltriacetoxysilane, ethyltriacetoxysilane, and vinyltriacetoxysilane; and partial hydrolysis condensates of these silanes. These may be used alone or in combination of two or more.

[0027] Regarding the blending ratios of the above components (A), (B), and (C), when the hydrolyzable aminoalkylsilane and / or its condensation polymer of the component (A) contains a primary amino group, the amount of epoxy groups contained in the bifunctional epoxy monomer and / or its polymer of the component (B) is preferably 2 to 20 moles, particularly 2 to 10 moles, per mole of primary amino group contained in the component (A); and the amount of hydrolyzable groups in the hydrolyzable organosilane compound and / or its partial hydrolyzed condensate of the component (C) is preferably 2 to 20 moles, particularly 2 to 10 moles, per mole of primary amino group contained in the hydrolyzable aminoalkylsilane and / or its condensation polymer of the component (A). Furthermore, when the aminoalkylsilane and / or condensation polymer thereof, component (A), contains a secondary amino group, the epoxy group contained in the bifunctional epoxy monomer and / or polymer thereof, component (B), is preferably 1 to 10 mol, particularly 1 to 5 mol, per mol of secondary amino group contained in component (A). Also, the hydrolyzable group in the hydrolyzable organosilane compound and / or partial hydrolyzed condensate thereof, component (C), is preferably 1 to 10 mol, particularly 1 to 5 mol, per mol of secondary amino group contained in the aminoalkylsilane and / or condensation polymer thereof, component (A). If the blending amount is outside the above range, problems such as gelation during the production of the primer composition or a significant decrease in the performance as a primer may occur.

[0028] -(D) Component- The component (D) is not particularly limited as long as it is an organic solvent other than an alcohol-based solvent that dissolves the above components (A), (B), and (C), the component (E) described below, and any optional components, and any known organic solvent can be used. If an alcohol-based solvent is used, there is a possibility that the other components will precipitate or the reaction will not proceed.

[0029] Examples of the (D) component include aromatic hydrocarbon solvents such as xylene, toluene, and benzene, aliphatic hydrocarbon solvents such as butane, heptane, hexane, and ligroin, ester solvents such as ethyl acetate and butyl acetate, and ether solvents such as tetrahydrofuran and diethyl ether. Among these, xylene, toluene, and hexane are preferably used. In addition, one type may be used alone, or two or more types may be used in combination.

[0030] The blending amount of the solvent of component (D) is 5 to 1000 parts by mass, and preferably 5 to 100 parts by mass, per 10 parts by mass of the total of components (A), (B), and (C). If the blending amount of component (D) is too small, workability deteriorates, and if it is too large, the performance as a primer is significantly reduced.

[0031] -(E) Component- Component (E) is a (meth)acrylic copolymer having an alkoxysilyl group, in particular an acrylic copolymer obtained by copolymerizing a monomer component containing a (meth)acrylic acid ester having an alkoxysilyl group and a (meth)acrylic acid ester not having an alkoxysilyl group, and has the function of forming a film on an adherend.

[0032] The acrylic copolymer constituting component (E) is obtained by copolymerizing monomer components including at least one type of (meth)acrylic acid ester having an alkoxysilyl group in the molecule (hereinafter referred to as alkoxysilyl group-containing component (E1)) and at least one type of (meth)acrylic acid ester not having an alkoxysilyl group in the molecule (hereinafter referred to as alkoxysilyl group-free component (E2)).

[0033] The polymerization method for copolymerizing the above-mentioned monomer components is not particularly limited, and examples thereof include radical polymerization, cationic polymerization, anionic polymerization, etc. Among them, random radical polymerization using an organic peroxide or an organic azo compound as an initiator is effective as a simple method.

[0034] The alkoxysilyl group-containing component (E1) is a monomer component containing at least one (meth)acrylic acid ester having an alkoxysilyl group in the molecule. In this monomer, the (meth)acrylic acid ester (E1) having an alkoxysilyl group can be used alone or in combination of two or more. The (meth)acrylic acid ester (E1) having an alkoxysilyl group has at least one, preferably two or three, alkoxysilyl groups in one molecule.

[0035] Examples of the (meth)acrylic acid ester containing an alkoxysilyl group in the molecule include 3-(meth)acryloxypropyltrimethoxysilane, 3-(meth)acryloxypropyltriethoxysilane, 3-(meth)acryloxypropylmethyldimethoxysilane, and 3-(meth)acryloxypropylmethyldiethoxysilane, and particularly preferred is 3-(meth)acryloxypropyltrimethoxysilane.

[0036] The content of the alkoxysilyl group-containing component (E1) is 1 to 30% by mass, and preferably 1 to 20% by mass, when the mass of the entire monomer components for obtaining the component (E) (the sum of the components (E1) and (E2)) is taken as 100% by mass. If the content of the component (E1) is less than 1% by mass or more than 30% by mass of the entire monomer components for obtaining the component (E), adhesion to the adherend is impaired.

[0037] The alkoxysilyl group-free component (E2) is a monomer component containing at least one (meth)acrylic acid ester that does not contain an alkoxysilyl group in the molecule. In this monomer, the (meth)acrylic acid ester (E2) that does not contain an alkoxysilyl group can be used alone or in combination of two or more.

[0038] The (meth)acrylic acid ester not containing an alkoxysilyl group is preferably an aliphatic hydrocarbon ester of (meth)acrylic acid, more preferably an alkyl (meth)acrylic acid ester having an alkyl group having 1 to 20 carbon atoms, and even more preferably an alkyl (meth)acrylic acid ester having an alkyl group having 1 to 10 carbon atoms.

[0039] Further, examples of (meth)acrylic acid esters not containing an alkoxysilyl group include acrylic acid esters such as methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, isopentyl acrylate, n-hexyl acrylate, isooctyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, and isobornyl acrylate; and methacrylic acid esters such as methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, isopentyl methacrylate, n-hexyl methacrylate, isooctyl methacrylate, 2-ethylhexyl methacrylate, n-octyl methacrylate, and isobornyl methacrylate.

[0040] The content of this alkoxysilyl group-free component (E2) is 70 to 99 mass%, preferably 80 to 99 mass%, when the mass of the entire monomer components for obtaining component (E) (the sum of components (E1) and (E2)) is taken as 100 mass%. If the content of component (E2) is less than 70 mass% or more than 99 mass% of the entire monomer components for obtaining component (E), the adhesion to the adherend is impaired.

[0041] The blending amount of component (E) is 2 to 100 parts by mass, and preferably 5 to 50 parts by mass, per 10 parts by mass of the total of components (A), (B), and (C). If the blending amount of component (E) is too small, the adhesiveness is impaired, whereas if the blending amount is too large, uneven coating is likely to occur when the composition is applied to an adherend.

[0042] -Other additives- In the method for producing the primer composition of the present invention, in addition to the above-mentioned components (A) to (E), the primer composition may further contain at least one known additive selected from pigments, dyes, antioxidants, antioxidants, adhesion promoters, antistatic agents, and flame retardants such as antimony oxide and chlorinated paraffin, as an additive, within a range that does not impair the object of the present invention. Furthermore, mildew inhibitors, antibacterial agents, etc. may also be added within a range that does not impair the object of the present invention.

[0043] In the present invention, the primer composition comprises: [i] a step of mixing all or a part of the above components (A), (B), (C), and (D) under reflux stirring at 20 to 150° C. for 6 to 120 hours in a moisture-free environment to prepare a homogeneous reaction mixture; and [ii] A step of adding the remainder of component (D) and component (E) to the reaction mixture prepared in step [i] under moisture protection, and mixing at 20 to 60°C to prepare a homogeneous composition. The present invention is produced by a production method including the steps of:

[0044] The order in which the above-mentioned other additives, which are optional components that are added as necessary, are added is not particularly limited, but it is preferable that they are added in step [ii].

[0045] In step [i], the reaction of components (A), (B), and (C) should proceed. The reaction conditions are, in a moisture-free environment, reflux stirring at 20 to 150°C for 6 to 120 hours, preferably 60°C to 120°C for 8 to 48 hours.

[0046] In step [ii], the remaining amount of component (D) and component (E) are mixed with the reaction mixture of some or all of the above components (A), (B), (C), and (D) obtained in step [i] under conditions of 20 to 60°C (e.g., room temperature (20°C or higher but lower than 40°C) or heated to about 40 to 60°C as necessary) in a moisture-proof state, and the mixing time may be sufficient to make the above components uniform, and is usually about 30 minutes to 4 hours.

[0047] In addition, if all of the components (A) to (E) are mixed together in step [i], the reaction between the components (A), (B), and (C) will be delayed or will not proceed, resulting in a significant impairment of the performance as a primer.

[0048] [Primer composition] The primer composition according to the present invention is produced by the above-mentioned production method, (A) a hydrolyzable aminoalkylsilane and / or a condensation polymer thereof, (B) a difunctional epoxy monomer and / or a polymer thereof, (C) a hydrolyzable organosilane compound other than the component (A) and / or a partial hydrolysis condensate thereof, (D) non-alcoholic organic solvents, and (E) (Meth)acrylic copolymer having an alkoxysilyl group A primer composition comprising: The present invention is characterized in that it contains a part or all of the above components (A), (B), (C) and (D) as a heated reaction mixture. The components (A) to (E) are as described above.

[0049] Here, the above-mentioned heated reaction mixture is preferably a reaction mixture of all or some of the components (A), (B), (C), and (D) heated at 60 to 150°C. Also, the primer composition of the present invention is preferably for wet surface adhesion.

[0050] The primer composition produced as described above can be suitably used to improve the adhesion between the adherend and the silicone cured product, which is the cured product of the room temperature curable organopolysiloxane composition.As a method for bonding the adherend and the silicone cured product using the primer composition of the present invention, for example, the primer composition of the present invention is applied to the adherend with a brush or nonwoven fabric, and air-dried at room temperature (23 ° C) for 30 minutes to 12 hours, preferably about 30 minutes to 2 hours, and then the room temperature curable organopolysiloxane composition is applied, and the organopolysiloxane composition is cured at room temperature (23 ° C), thereby bonding the adherend and the silicone cured product, which is the cured product of the room temperature curable organopolysiloxane composition.

[0051] According to the present invention, after the surface of an adherend such as concrete is treated with a primer, a room temperature curable organopolysiloxane composition is applied and the film is cured, so that the applied (applied and cured) area exhibits good adhesion even after immersion in water. In addition, even if the surface of an adherend such as concrete is wet, the composition can be applied (applied and cured) without drying the wet surface, and still maintain good adhesion to the adherend. EXAMPLES

[0052] The present invention will be specifically described below with reference to examples and comparative examples, but the present invention is not limited to the following examples. Note that the number of moles in the following examples is when "parts by mass" is "g". Room temperature means 23°C.

[0053] [Preparation of acrylic copolymer] 34 parts by mass (34.0 mmol) of methyl methacrylate and 1.8 parts by mass (7.3 mmol) of 3-methacryloxypropyltrimethoxysilane were added to 47 parts by mass of ethyl acetate, mixed uniformly under nitrogen aeration, and heated to a temperature of 80°C. Next, 0.1 parts by mass of 2,2'-azobis(2-methylbutyronitrile) was added and mixed to dissolve. The mixture was then aged at 80°C for 3 hours to allow the polymerization reaction to proceed, and then cooled to 40°C or lower. After cooling, 0.02 parts by mass of 4-methoxyphenol was added to stop the reaction, and a colorless and transparent acrylic copolymer solution (ethyl acetate solution of methyl methacrylate-3-methacryloxypropyltrimethoxysilane copolymer) was obtained.

[0054] [Example 1] To 1.2 parts by mass (6.7 mmol) of γ-aminopropyltrimethoxysilane, 6.9 parts by mass (20.3 mmol) of bisphenol A diglycidyl ether, 1.9 parts by mass (13.9 mmol) of methyltrimethoxysilane, and 9.8 parts by mass of toluene were added, and the mixture was refluxed in a reflux condenser under moisture protection, and stirred at 60°C for 8 hours to prepare a homogeneous reaction mixture (step [i]). Next, 8.2 parts by mass of the acrylic copolymer solution obtained in [Preparation of acrylic copolymer] was added, and the mixture was mixed uniformly at room temperature for 1 hour to obtain a homogeneous composition 1 (step [ii]).

[0055] [Example 2] A homogeneous composition 2 was obtained in the same manner as in Example 1, except that in the manufacturing method of Example 1, 1.5 parts by mass (6.8 mmol) of γ-aminopropyltriethoxysilane was used instead of 1.2 parts by mass of γ-aminopropyltrimethoxysilane in step [i], 6.7 parts by mass (19.7 mmol) of bisphenol A diglycidyl ether was used instead of 6.9 parts by mass of bisphenol A diglycidyl ether, and 1.8 parts by mass (13.2 mmol) of methyltrimethoxysilane was used instead of 1.9 parts by mass of methyltrimethoxysilane.

[0056] [Example 3] A homogeneous composition 3 was obtained in the same manner as in Example 1, except that in the manufacturing method of Example 1, 1.2 parts by mass of γ-aminopropyltrimethoxysilane was replaced with 1.9 parts by mass (9.8 mmol) of [3-(methylamino)propyl]trimethoxysilane, 6.7 parts by mass (19.7 mmol) of bisphenol A diglycidyl ether was replaced with 6.9 parts by mass of bisphenol A diglycidyl ether, and 1.4 parts by mass (10.3 mmol) of methyltrimethoxysilane was replaced with 1.9 parts by mass of methyltrimethoxysilane in step [i].

[0057] [Comparative Example 1] A homogeneous composition 4 was obtained in the same manner as in Example 1, except that in step [i], stirring was performed at 20°C for 30 minutes instead of at 60°C for 8 hours.

[0058] [Comparative Example 2] Composition 5 was obtained in the same manner as in Example 1, except that in the production method of Example 1, 9.8 parts by mass of methanol was used instead of 9.8 parts by mass of toluene in step [i]. Composition 5 was cloudy and contained some precipitates, and its physical properties could not be evaluated.

[0059] [Comparative Example 3] A homogeneous composition 6 was obtained in the same manner as in Example 1, except that 1.9 parts by mass of methyltrimethoxysilane was not used in the production method of Example 1. Since composition 6 significantly increased in viscosity over time after production, its physical properties could not be evaluated.

[0060] [Comparative Example 4] A homogeneous composition 7 was obtained in the same manner as in Example 1, except that in the manufacturing method of Example 1, 1.9 parts by mass (10.6 mmol) of γ-aminopropyltrimethoxysilane was used instead of 1.2 parts by mass of γ-aminopropyltrimethoxysilane, 2.6 parts by mass (11.0 mmol) of 3-glycidoxypropyltrimethoxysilane was used instead of 6.9 parts by mass of bisphenol A diglycidyl ether, and 1.5 parts by mass (11.0 mmol) of methyltrimethoxysilane was used instead of 1.9 parts by mass of methyltrimethoxysilane.

[0061] [Adhesion evaluation] The adhesion of each of the primer compositions obtained in Examples 1 to 3 and Comparative Examples 1 and 4 to a hardened cement mortar, which is an adherend, was evaluated by the following method.

[0062] [Preparation of test specimen] Each primer composition obtained in Examples 1 to 3 and Comparative Examples 1 and 4 was applied with a brush to the flat surface of the hardened cement mortar, and left for 30 minutes under conditions of a temperature of 23°C and a humidity of 50% RH. Then, a one-component silicone sealant of the oxime-free type (Sealant 45: manufactured by Shin-Etsu Chemical Co., Ltd.) was applied to the surface of the hardened cement mortar to prepare a test specimen. The application area of ​​the silicone sealant was approximately 5 cm2. 2 It is.

[0063] [Adhesion test] After curing this test piece under the following conditions, the cured silicone sealant was cut with a knife and the cut part was peeled off by hand (grabbing it with fingers and pulling it), and the peeling condition was observed to evaluate the condition of the adhesive interface between the adherend and the primer composition.

[0064] [Initial adhesion] The initial adhesion was evaluated by the knife-cut manual peel test after aging for 7 days under conditions of 23°C temperature and 50% RH. The evaluation was performed as follows: 100% of the sealant had a cohesive failure area; 80% or more but less than 100%; △; 50% or more but less than 80%; and x; less than 50%. Table 1 shows the initial adhesion test results when each primer composition was used.

[0065] [Water resistant adhesion] The waterproof adhesion was evaluated in the same manner as the initial adhesion test after aging for 7 days under conditions of a temperature of 23°C and a humidity of 50% RH, followed by immersion in 50°C warm water for 7 days. The waterproof adhesion test results when each primer composition was used are shown in Table 1.

[0066] [Wet surface adhesion] For wet surface adhesion, the hardened cement mortar was immersed in water (room temperature: 23°C) for at least one day, and 30 minutes after removal from the water, the above-mentioned [Preparation of test specimens] was carried out to prepare test specimens. After curing for 7 days under conditions of a temperature of 23°C and a humidity of 50% RH, evaluation was performed in the same manner as in the test method for initial adhesion. The test results for wet surface adhesion when each primer composition was used are shown in Table 1.

[0067] [ka]

[0068] From the results in Table 1, Examples 1 to 3 showed good adhesion to wet surfaces even after immersion in water. On the other hand, Comparative Example 1 showed poor adhesion to wet surfaces even after immersion in water. Comparative Example 4 showed relatively good adhesion after immersion in water, but did not adhere to wet surfaces.

Claims

1. (A) a hydrolyzable aminoalkylsilane and / or a condensation polymer thereof, (B) a difunctional epoxy monomer and / or a polymer thereof, (C) a hydrolyzable organosilane compound other than the component (A) and / or a partial hydrolysis condensate thereof, (D) a non-alcoholic organic solvent, and (E) (Meth)acrylic copolymer having an alkoxysilyl group A method for producing a primer composition comprising: [i] a step of mixing all or part of the components (A), (B), (C), and (D) under reflux stirring at 20 to 150° C. for 6 to 120 hours in a moisture-free environment to prepare a homogeneous reaction mixture; and [ii] adding the remainder of component (D) and component (E) to the reaction mixture prepared in step [i] under moisture protection, and mixing at 20 to 60° C. to prepare a homogeneous composition; A method for producing a primer composition comprising the steps of:

2. 2. The method for producing a primer composition according to claim 1, wherein the (meth)acrylic copolymer of component (E) is a copolymer of a (meth)acrylic acid ester monomer having an alkoxysilyl group and a (meth)acrylic acid ester monomer not having an alkoxysilyl group.

3. 2. The method for producing a primer composition according to claim 1, wherein the hydrolyzable aminoalkylsilane constituting component (A) is a silane compound represented by the following formula (1): R 1 R 2 a SiX (3-a) (1) (In the formula, R 1 is an alkyl group having 1 to 10 carbon atoms substituted with a primary amino group and / or a secondary amino group, R 2 is a monovalent hydrocarbon group having 1 to 10 carbon atoms, X is a hydrolyzable group, and a is 0 or 1.

4. 2. The method for producing a primer composition according to claim 1, wherein the molar ratio of the epoxy groups contained in component (B) to the primary amino groups contained in component (A) is 2 to 20, and the molar ratio of the hydrolyzable groups in the hydrolyzable organosilane compound and / or its partial hydrolyzed condensate, component (C), to the primary amino groups contained in component (A) is 2 to 20.

5. 2. The method for producing a primer composition according to claim 1, wherein the molar ratio of the epoxy groups contained in component (B) to the secondary amino groups contained in component (A) is 1 to 10, and the molar ratio of the hydrolyzable groups in the hydrolyzable organosilane compound and / or its partial hydrolyzed condensate, component (C), to the secondary amino groups contained in component (A) is 1 to 10.

6. 2. The method for producing a primer composition according to claim 1, comprising: 5 to 1,000 parts by mass of the (D) component and 2 to 100 parts by mass of the (E) component relative to a total of 10 parts by mass of the (A) component, the (B) component, and the (C) component.

7. (A) a hydrolyzable aminoalkylsilane and / or a condensation polymer thereof, (B) a difunctional epoxy monomer and / or a polymer thereof, (C) a hydrolyzable organosilane compound other than the component (A) and / or a partial hydrolysis condensate thereof, (D) a non-alcoholic organic solvent, and (E) (Meth)acrylic copolymer having an alkoxysilyl group A primer composition comprising: A primer composition comprising all or a part of the above components (A), (B), (C) and (D) as a heat-reacted mixture thereof.

8. 8. The primer composition according to claim 7, wherein the heated reaction mixture is a 60 to 150° C. heated reaction mixture of all or a part of the components (A), (B), (C) and (D).

9. The primer composition of claim 7 for wet surface adhesion.

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