Aqueous primer composition

Abstract

The present invention provides an aqueous primer composition which has excellent adhesiveness and is capable of improving water resistance and storage stability. The present invention relates to an aqueous primer composition comprising an organic polymer dispersed in an aqueous medium, the aqueous primer composition comprising: (A) a copolymer comprising a cationic acrylic polymer; (B) A bisphenol epoxy resin. The aqueous primer composition can be suitably used as a sealing material.

Description

Technical Field

[0001] The invention relates to a waterborne primer composition. Background Art

[0002] In order to make the building sealant bond to the adherends such as aluminum and mortar, the sealant is usually applied to the adherend after the primer is applied in advance. By applying the primer, the bonding force between the adherend and the sealant is improved. Such primers mostly contain organic solvents. If the primer containing organic solvents is used at the construction site, the primer may have the smell of organic solvents, the organic solvent has flammability, the safety of the operator and other problems. Therefore, it is necessary to develop a primer that does not contain organic solvents. As such water-based primers, patent documents 1 and 2 have been reported.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Publication No. 7-122034

[0006] Patent Document 2: International Publication No. 2014 / 0580123 Summary of the invention

[0007] Problems to be solved by the invention

[0008] Problems of water-based primers include poor wettability with adherends and poor adhesion between adherends and sealing materials. Patent Documents 1 and 2 have improved these problems, but further improvements are needed.

[0009] Furthermore, as problems of the water-based primer, it is required to improve water resistance and storage stability.

[0010] Technical means to solve problems

[0011] The inventors of the present invention have conducted intensive research and found that an aqueous primer composition comprising (A) a copolymer comprising a cationic acrylic polymer and (B) a bisphenol-type epoxy resin has excellent adhesion and can improve water resistance and storage stability, thereby completing the present invention.

[0012] This specification includes the following embodiments.

[0013] 1. A waterborne primer composition comprising an organic polymer dispersed in an aqueous medium, comprising:

[0014] (A) a copolymer comprising a cationic acrylic polymer;

[0015] (B) Bisphenol type epoxy resin.

[0016] 2. The water-based primer composition according to 1 above, wherein a portion of the copolymer (A) containing a cationic acrylic polymer contains a quaternary ammonium group derived from epichlorohydrin and an amino group.

[0017] 3. The water-based primer composition according to 1 or 2 above, wherein a part of the copolymer (A) comprising a cationic acrylic polymer further contains a reactive silyl group.

[0018] 4. The water-based primer composition according to any one of 1 to 3 above, further comprising a silane coupling agent, wherein the silane coupling agent comprises at least one selected from a silane coupling agent having an amino group and a silane coupling agent having an epoxy group.

[0019] 5. The water-based primer composition according to any one of 1 to 4 above, which is neutralized with (C) an acid.

[0020] 6. The aqueous primer composition for a sealant according to any one of 1 to 5 above, which is used between a sealant and an adherend.

[0021] 7. A method for using a water-based primer composition, comprising:

[0022] Applying the water-based primer composition described in any one of 1 to 6 above to an adherend to form a primer layer;

[0023] A sealing material is applied over the primer layer.

[0024] Effects of the Invention

[0025] The water-based primer composition of the embodiment of the present invention comprises (A) a copolymer comprising a cationic acrylic polymer and (B) a bisphenol epoxy resin, has excellent adhesion, and can improve water resistance and storage stability. Therefore, the water-based primer composition of the embodiment of the present invention is suitable for use in architectural adherends. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A test body for evaluating the simple adhesion of a water-based primer composition is schematically shown. DETAILED DESCRIPTION

[0027] One aspect of the present invention discloses a waterborne primer composition comprising an organic polymer dispersed in an aqueous medium, the waterborne primer composition comprising:

[0028] (A) a copolymer comprising a cationic acrylic polymer; and

[0029] (B) Bisphenol type epoxy resin.

[0030] The water-based primer composition according to an embodiment of the present invention includes an organic polymer dispersed in an aqueous medium.

[0031] The aqueous medium is not particularly limited as long as the target aqueous primer composition of the present invention can be obtained, and includes, for example, so-called water such as ion-exchanged water, distilled water, tap water, and a dispersion medium or solvent miscible with water.

[0032] The organic polymer includes (A) a copolymer including a cationic acrylic polymer and (B) a bisphenol epoxy resin, and may include other organic polymers as long as the target water-based primer composition of the present invention can be obtained.

[0033] The organic polymer is dispersed in the aqueous medium, which may be in a liquid phase, a solid phase, or a combination of a liquid phase and a solid phase. Therefore, the aqueous primer composition of the embodiment of the present invention includes the concepts of both "emulsion" and "suspension".

[0034] In the present specification, (A) a copolymer containing a cationic acrylic polymer (also referred to as (A) copolymer) is a copolymer containing a polymer having a cationic group obtained by polymerizing at least one selected from acrylates and methacrylates, and there is no particular limitation as long as the target water-based primer composition of the present invention can be obtained.

[0035] In this specification, acrylic acid and methacrylic acid are also collectively referred to as (meth)acrylic acid. Acrylic acid ester and methacrylic acid ester are also collectively referred to as (meth)acrylate.

[0036] There are no particular limitations on the acrylates and methacrylates as long as the target water-based primer composition of the present invention can be obtained. Examples thereof include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, sec-butyl (meth)acrylate, tert-butyl (meth)acrylate, n-pentyl (meth)acrylate, isopentyl (meth)acrylate, n-hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and n-octyl (meth)acrylate. , isooctyl (meth)acrylate, n-nonyl (meth)acrylate, isononyl (meth)acrylate, n-decyl (meth)acrylate, isodecyl (meth)acrylate, n-dodecyl (meth)acrylate, isomyristyl (meth)acrylate, n-tridecyl (meth)acrylate, n-tetradecyl (meth)acrylate and the like alkyl (meth)acrylates; cyclopentyl (meth)acrylate, cyclohexyl (meth)acrylate, tert-butylcyclohexyl (meth)acrylate, cyclooctyl (meth)acrylate and the like cycloalkyl (meth)acrylates.

[0037] Examples of the cationic group include quaternary ammonium groups derived from tertiary amino groups. Examples of such tertiary amino groups include dialkylamino groups such as dimethylamino, diethylamino, dibutylamino, dihexylamino, di-tert-butylamino, diisohexylamino, and di-tert-butylamino; and pyridine groups such as pyridine and 2-methylpyridine.

[0038] There is no particular limitation on the method for introducing the tertiary amino group into the copolymer (A) as long as the target waterborne primer composition of the present invention can be obtained. For example, there can be mentioned a method of copolymerizing a monomer having a tertiary amino group with at least one selected from the above acrylates and methacrylates.

[0039] Examples of the monomer having a tertiary amino group include: N,N-dialkylaminoalkyl (meth)acrylates such as dimethylaminomethyl (meth)acrylate, diethylaminomethyl (meth)acrylate, dibutylaminomethyl (meth)acrylate, dihexylaminomethyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, di-tert-butylaminoethyl (meth)acrylate, diisohexylaminoethyl (meth)acrylate, dihexylaminopropyl (meth)acrylate, and di-tert-butylaminohexyl (meth)acrylate; vinyl pyridines such as vinyl pyridine and 2-methylvinyl pyridine; N,N-dimethylaminoalkyl vinyl ethers such as dimethylaminovinyl ether; and N,N-dimethylaminoethylalkylamides.

[0040] Examples of the quaternary ammonium group derived from a tertiary amino group include a quaternary ammonium group derived from a tertiary amino group and, for example, epichlorohydrin. More preferred is a quaternary ammonium group derived from a tertiary amino group and epichlorohydrin.

[0041] The amount of epichlorohydrin may be, for example, 0.1 to 15 parts by mass, 1 to 12 parts by mass, or 2 to 10 parts by mass based on 100 parts by mass of the (A) cationic acrylic polymer-containing copolymer (excluding the aqueous medium).

[0042] (A) A part of the copolymer containing a cationic acrylic polymer may further contain a reactive silyl group.

[0043] In the present specification, the reactive silyl group refers to a group which is hydrolyzed to form a silanol group in the presence of water, and further silanol groups react with each other to form a siloxane bond, and is not particularly limited as long as the target water-based primer composition of the present invention can be obtained.

[0044] Examples of the reactive silyl group include: trialkoxysilyl groups such as trimethoxysilyl, triethoxysilyl, tripropoxysilyl, triisopropoxysilyl, tributoxysilyl, triisobutoxysilyl, tri-sec-butoxysilyl, and tri-tert-butoxysilyl; alkyldialkoxysilyl groups such as methyldimethoxysilyl, methyldiethoxysilyl, methyldipropoxysilyl, methyldibutoxysilyl, ethyldimethoxysilyl, ethyldiethoxysilyl, ethyldipropoxysilyl, ethyldibutoxysilyl, propyldimethoxysilyl, propyldiethoxysilyl, propyldipropoxysilyl, and propyldibutoxysilyl; and dialkyl(mono)alkoxysilyl groups corresponding to these groups.

[0045] Preferred are triethoxysilyl, tripropoxysilyl, diethoxysilyl (such as methyldiethoxysilyl and ethyldiethoxysilyl), and dipropoxysilyl (such as methyldipropoxysilyl and ethyldipropoxysilyl).

[0046] There is no particular limitation on the method for introducing the reactive silyl group into the copolymer (A) as long as the target aqueous primer composition of the present invention can be obtained. Examples thereof include a method of copolymerizing a monomer having a reactive silyl group with at least one selected from the above acrylates and methacrylates.

[0047] Examples of the monomer having a reactive silyl group include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltripropoxysilane, vinylmethyldimethoxysilane, vinylmethyldiethoxysilane, vinylmethyldipropoxysilane, γ-acryloxypropyltrimethoxysilane, γ-acryloxypropyltriethoxysilane, γ-acryloxypropyltripropoxysilane, γ-acryloxypropylmethyldimethoxysilane, γ-acryloxypropylmethyldiethoxysilane, γ-acryloxypropylmethyldipropoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-methacryloxypropyltripropoxysilane, γ-methacryloxypropylmethyldimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, and γ-methacryloxypropylmethyldipropoxysilane. These monomers may be used alone or in combination.

[0048] The (A) copolymer may be polymerized with monomers other than the above-mentioned monomers as long as the target aqueous primer composition of the present invention can be obtained.

[0049] As such a monomer, the following monomers can be exemplified:

[0050] α-olefins such as ethylene, propylene, and isobutylene;

[0051] α,β-unsaturated monocarboxylic acids or dicarboxylic acids such as acrylic acid, methacrylic acid, maleic acid, fumaric acid, and itaconic acid;

[0052] Amides of α,β-unsaturated monocarboxylic acids or dicarboxylic acids such as acrylamide and methacrylamide;

[0053] N-hydroxymethylamide;

[0054] Ethylene glycol esters;

[0055] Dialkyl esters such as dialkyl maleates, dialkyl fumarates, and dialkyl itaconic acids;

[0056] Vinyl esters such as vinyl acetate, vinyl propionate, and versatic acid vinyl ester;

[0057] Aromatic vinyl compounds such as styrene and vinyltoluene;

[0058] Vinyl halides such as vinyl chloride and vinylidene chloride;

[0059] Vinyl ethers such as methyl vinyl ether;

[0060] Dienes such as butadiene.

[0061] The (A) copolymer may be neutralized with the (C) acid.

[0062] The acid can neutralize the basicity of the aqueous primer composition due to the cationic groups of the copolymer (A), and is not particularly limited as long as the target aqueous primer composition of the present invention can be obtained.

[0063] Examples of the acid include organic acids such as formic acid, acetic acid, and oxalic acid, and inorganic acids such as hydrochloric acid, sulfuric acid, and nitric acid, preferably organic acids, more preferably formic acid and acetic acid. If the acid (C) is used for neutralization, the distance between particles during film formation is shortened, and a more uniform film is formed.

[0064] The (A) copolymer can be dispersed in an aqueous medium, and its particle size is, for example, 10 nm to 900 nm, preferably 12 nm to 500 nm, more preferably 15 nm to 450 nm, further preferably 17 nm to 400 nm, and further preferably 20 nm to 300 nm. When the particle size of the (A) copolymer is 10 nm to 900 nm, it is observed that the permeability, wettability, and affinity to the adherend tend to be improved, and a tendency to improve the adhesiveness is observed.

[0065] The particle size of the copolymer (A) can be measured at 25° C. using a thick-type particle size analyzer “FPAR-1000” (analyzer manufactured by Otsuka Electronics Co., Ltd.).

[0066] The Tg (glass transition temperature) of the copolymer (A) is, for example, -50 to 100° C., preferably -20 to 80° C., more preferably -10 to 60° C., and further preferably 0 to 45° C. When the Tg of the copolymer (A) is -50 to 100° C., the adhesiveness is more excellent.

[0067] It should be noted that the Tg of the copolymer (A) was measured by a dynamic viscoelasticity test using "Reogel E4000" (a dynamic viscoelasticity measuring apparatus manufactured by UBM Co., Ltd.) under the conditions of a measurement start temperature of 10°C, a measurement end temperature of 170°C, a heating rate of 4°C / min, a step temperature of 1°C, and a frequency of 1 Hz.

[0068] The MFT (Minimum Film-forming Temperature) of the (A) copolymer is, for example, 0° C. to 60° C., preferably 0° C. to 40° C., more preferably 0° C. to 20° C., and further preferably 0° C. to 5° C. When the MFT of the (A) copolymer is 0° C. to 60° C., the film-forming property at low temperature is more excellent.

[0069] In addition, the MFT of the (A) copolymer can be measured using a minimum film forming temperature meter (manufactured by Rhopoint Instrument Co., Ltd.: MFFTB90).

[0070] For the water-based primer composition of the embodiment of the present invention, per 100 parts by mass of the water-based primer composition (excluding the aqueous medium), it can contain, for example, 10 to 90 parts by mass of the (A) copolymer, preferably 20 to 70 parts by mass of the (A) copolymer, more preferably 25 to 60 parts by mass of the (A) copolymer, and more preferably 30 to 45 parts by mass of the (A) copolymer.

[0071] When the aqueous primer composition according to the embodiment of the present invention contains 10 to 90 parts by mass of the (A) copolymer per 100 parts by mass of the aqueous primer composition (excluding the aqueous medium), the adhesiveness to mortar is more excellent.

[0072] As the (A) copolymer, commercially available products can be used. Examples of such commercially available products include UW-600 (trade name) manufactured by Taisei Fine Chemical Co., Ltd., 3KW-3000 (trade name) manufactured by Taisei Fine Chemical Co., Ltd., KD-20 (trade name) manufactured by Henkel Japan, Ltd., Aron NW-400 (trade name) manufactured by Toagosei Co., Ltd., Aron A-3611A (trade name) manufactured by Toagosei Co., Ltd., Aron NW-7060 (trade name) manufactured by Toagosei Co., Ltd., Neocryl XK-12 (trade name) manufactured by Kusumoto Chemicals Co., Ltd., Neocryl XK-16 (trade name) manufactured by Kusumoto Chemicals Co., Ltd., and ACRONAL YS-800ap (trade name) manufactured by BASF Japan Ltd.

[0073] In this specification, (B) bisphenol-type epoxy resin refers to a thermosetting resin having a bisphenol skeleton and utilizing the existing epoxy groups to form a cross-linked network so as to be cured, and is generally referred to as epoxy resin. There is no particular limitation as long as the target water-based primer composition of the present invention can be obtained.

[0074] (B) The bisphenol type epoxy resin may be, for example, a glycidyl ether type epoxy resin, a glycidyl amine type epoxy resin, a glycidyl ester type epoxy resin, or the like.

[0075] (B) The bisphenol-type epoxy resin is an epoxy resin having a bisphenol skeleton and is not particularly limited as long as the target water-based primer composition of the present invention can be obtained.

[0076] Examples of the bisphenol-type epoxy resin include diglycidyl ethers of bisphenol A, bisphenol F, brominated bisphenol A, and bisphenol AD.

[0077] The epoxy equivalent of the bisphenol epoxy resin is preferably 200 g / eq to 5000 g / eq, more preferably 300 g / eq to 2500 g / eq, further preferably 700 g / eq to 1500 g / eq, and further preferably 500 g / eq to 1100 g / eq. When the epoxy equivalent of the bisphenol epoxy resin is 200 g / eq to 5000 g / eq, the adhesiveness to acrylic electrodeposition-coated aluminum and the water-resistant adhesiveness to porous members are more excellent.

[0078] The epoxy equivalent of the bisphenol epoxy resin can be measured by the potentiometric titration method according to JIS K 7236. The measurement can be performed using a commercially available potentiometric titrator (for example, AT-610 manufactured by Kyoto Electronics Co., Ltd.).

[0079] The bisphenol epoxy resin can be dispersed in an aqueous medium. When the bisphenol epoxy resin is dispersed in an aqueous medium, the aqueous primer composition of an embodiment of the present invention comprises an organic polymer and a bisphenol epoxy resin dispersed in an aqueous medium. The particle size of the bisphenol epoxy resin is preferably 100nm to 1000nm, more preferably 150nm to 800nm, further preferably 200nm to 700nm, and further preferably 300nm to 600nm. When the particle size of the bisphenol epoxy resin is 100nm to 1000nm, the water-resistant adhesion to porous components is more excellent.

[0080] In addition, the particle diameter of a bisphenol type epoxy resin can be measured using a thick type particle size analyzer "FPAR-1000" (analyzer of Otsuka Electronics Co., Ltd.).

[0081] In the water-based primer composition of the embodiment of the present invention, for every 100 parts by mass of the water-based primer composition (excluding the aqueous medium), it can contain, for example, 10 to 90 parts by mass of (B) bisphenol-type epoxy resin, preferably 20 to 80 parts by mass of (B) bisphenol-type epoxy resin, more preferably 30 to 70 parts by mass of (B) bisphenol-type epoxy resin, further preferably 30 to 75 parts by mass of (B) bisphenol-type epoxy resin, and even more preferably 50 to 70 parts by mass of (B) bisphenol-type epoxy resin.

[0082] When the aqueous primer composition according to the embodiment of the present invention contains 10 to 90 parts by mass of the (B) bisphenol epoxy resin per 100 parts by mass of the aqueous primer composition (excluding the aqueous medium), the hardness and water resistance of the coating film are further improved.

[0083] As the bisphenol epoxy resin, a commercially available product may be used. Examples of such commercially available products include EM-101-50 (trade name) manufactured by ADEKA Co., Ltd. and jERW2821R70 (trade name) manufactured by Mitsubishi Chemical Co., Ltd.

[0084] The ratio of (A) copolymer to (B) bisphenol-type epoxy resin ((A) / (B)) (mass ratio) is not particularly limited as long as the target aqueous primer composition of the present invention can be obtained, and is, for example, 80 / 20 to 20 / 80, preferably 70 / 30 to 25 / 75, more preferably 65 / 35 to 30 / 70, and further preferably 55 / 45 to 35 / 65.

[0085] When the ratio (A) of the copolymer to (B) the bisphenol-type epoxy resin ((A) / (B)) (mass ratio) is 80 / 20 to 20 / 80, the joint adhesiveness is excellent.

[0086] The water-based primer composition of the embodiment of the present invention may further include a silane coupling agent. In this specification, a silane coupling agent is a compound including Si, a compound having a site for reacting with an organic compound and a site for reacting with an inorganic compound, and is not particularly limited as long as the target water-based primer composition of the present invention can be obtained. As a silane coupling agent, examples such as: a silane coupling agent with an amino group, a silane coupling agent with an epoxy group, a silane coupling agent with a hydroxyl group, a silane coupling agent with a mercapto group, a silane coupling agent with an olefinic double bond, etc., preferably including at least one selected from a silane coupling agent with an amino group and a silane coupling agent with an epoxy group.

[0087] The Si-containing group (silyl group) of the silane coupling agent preferably contains a trimethoxy group, a methyldimethoxy group, a triethoxy group, or a methyldiethoxy group.

[0088] More specifically, the silane coupling agent includes, for example, silane coupling agents having an amino group such as N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N-(1,3-dimethylbutylene)propylamine, and N-phenyl-3-aminopropyltrimethoxysilane; and silane coupling agents having an epoxy group such as 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, and 3-glycidoxypropylmethyldimethoxysilane.

[0089] When the water-based primer composition according to the embodiment of the present invention contains at least one selected from a silane coupling agent having an amino group and a silane coupling agent having an epoxy group, it is possible to obtain a beneficial effect of excellent adhesion after durability.

[0090] The silane coupling agent more preferably comprises a reactant of a silane coupling agent having an amino group and a silane coupling agent having an epoxy group. The reactant of a silane coupling agent having an amino group and a silane coupling agent having an epoxy group can be obtained by mixing and then heating appropriately. The reactant more preferably comprises a compound containing two or more alkoxy groups, NH groups and OH groups in the molecule (equivalent to a silane coupling agent having an amino group).

[0091] The reaction ratio of the silane coupling agent having an amino group and the silane coupling agent having an epoxy group (silane coupling agent having an amino group / silane coupling agent having an epoxy group) is not particularly limited. For example, the weight ratio of the silane coupling agent having an amino group and the silane coupling agent having an epoxy group may be 1 / 1 to 5 / 1, preferably 1 / 1 to 4 / 1, more preferably 2 / 1 to 3.5 / 1, and particularly preferably 3 / 1.

[0092] In the case where the silane coupling agent includes a reactant of a silane coupling agent having an amino group and a silane coupling agent having an epoxy group, both the adhesiveness and the storage stability are more excellent.

[0093] The aqueous primer composition of the embodiment of the present invention preferably contains 0.1 to 5 parts by mass of a silane coupling agent, more preferably 0.5 to 3 parts by mass of a silane coupling agent, and further preferably 0.8 to 2 parts by mass of a silane coupling agent, relative to 100 parts by mass of the aqueous primer composition (excluding the aqueous medium).

[0094] For the water-based primer composition of the embodiment of the present invention, when it contains 0.1 to 5 parts by mass of a silane coupling agent relative to 100 parts by mass of the water-based primer composition (excluding the aqueous medium), and contains at least one selected from a silane coupling agent having an amino group and a silane coupling agent having an epoxy group, a beneficial effect of better adhesion after durability can be obtained.

[0095] The aqueous primer composition of an embodiment of the present invention may contain, for example, 50 to 90 parts by mass of an aqueous medium, preferably 60 to 85 parts by mass of an aqueous medium, and more preferably 65 to 80 parts by mass of an aqueous medium, relative to 100 parts by mass of the aqueous primer composition (including an aqueous medium).

[0096] When the aqueous primer composition of the embodiment of the present invention contains 50 to 90 parts by mass of the aqueous medium relative to 100 parts by mass of the aqueous primer composition (including the aqueous medium), a beneficial effect of better workability can be obtained.

[0097] For the water-based primer composition of the embodiment of the present invention, except the above-mentioned components, as long as the target water-based primer composition of the present invention can be obtained, additives can be further included as required. As additives, for example, fillers, pigments, antiblocking agents (antiblocking agent), dispersion stabilizers, thixotropic agents (thixotropy), viscosity modifiers, leveling agents, anti-gelling agents, light stabilizers, anti-aging agents, antioxidants, ultraviolet light absorbers, plasticizers, lubricants, antistatic agents, reinforcing materials, flame retardants, catalysts, defoamers, thickeners, dispersants, surfactants, film-forming aids, etc. can be enumerated. As long as the target water-based primer composition of the present invention can be obtained, the amount of these additives can be appropriately selected, and there is no particular restriction.

[0098] The method for producing the water-based primer composition according to the embodiment of the present invention is not particularly limited as long as the target water-based primer composition of the present invention can be obtained. For example, a method of producing by mixing the above-mentioned components can be exemplified.

[0099] The water-based primer composition of the embodiment of the present invention can be applied to various adherends. As long as it can be applied, the adherend is not particularly limited. As adherends to which the water-based primer composition of the embodiment of the present invention can be applied, for example, there can be cited: glass; metals such as aluminum, anodized aluminum, iron, zinc steel plate, copper, stainless steel; porous components such as mortar and stone; components coated with fluorine electrodeposition, acrylic electrodeposition, fluorine coating, polyurethane coating, acrylic polyurethane coating, etc.; cured products of sealing materials such as silicone, modified silicone, polyurethane, polysulfide, and polyisobutylene; vinyl chloride resin, acrylic resin; rubbers such as NBR and EPDM, etc.

[0100] The aqueous primer composition according to an embodiment of the present invention is applied to such an adherend to form a primer layer. Then, a sealing material may be applied on the primer layer.

[0101] Therefore, the water-based primer composition according to the embodiment of the present invention can be used between a sealing material and an adherend, and can be suitably used as a water-based primer composition for a sealing material.

[0102] The water-based primer composition according to the embodiment of the present invention can be suitably used as a primer used in, for example, building or automobile sealing materials.

[0103] As a method for using the water-based primer composition of an embodiment of the present invention, an example can be a method including the following steps: applying the water-based primer composition of an embodiment of the present invention on the above-mentioned adherend, and optionally drying to form a primer layer; applying a sealing material composition on the primer layer, and then drying and curing the water-based primer composition and the sealing material composition to form a sealing material layer.

[0104] As long as the target sealing material layer of the present invention can be formed, the sealing material used is not particularly limited, and conventionally known sealing materials can be used, preferably building sealing materials. Specifically, for example, silicone sealing materials, modified silicone sealing materials, polyurethane sealing materials, polysulfide sealing materials, etc. can be cited. Polyurethane sealing materials, particularly building polyurethane sealing materials, can be suitably used.

[0105] In a preferred aspect of the present invention, a method for using a novel water-based primer composition is provided, the method comprising: applying the water-based primer composition of an embodiment of the present invention to an adherend to form a primer layer; and applying a sealing material on the primer layer.

[0106] Example

[0107] Hereinafter, the present invention will be specifically and in detail described by examples and comparative examples, but these examples are only one embodiment of the present invention, and the present invention is not subject to any limitation of these examples. It should be noted that, in the description of the examples, as long as there is no special description, the part of water will not be considered as the basis of parts by weight and weight %.

[0108] The components used in this example are shown below.

[0109] (A) Copolymer containing a cationic acrylic polymer

[0110] (a1) Core-shell styrene acrylic emulsion (UW-600 (trade name) manufactured by Taisei Fine Chemical Co., Ltd.). Contains 34% by mass of solid content, a particle size of 60 nm, a core Tg of 20°C, a shell Tg of 20°C, an MFT of 4°C, and contains formic acid, a quaternary ammonium group obtained based on epichlorohydrin and an amino group, and dipropylene glycol monomethyl ether in addition to an acrylic styrene polymer, and also contains products generated by the reaction of components including the polymer component. The solid content is considered to substantially correspond to the (A) copolymer, and therefore, is considered to be the content of the (A) copolymer.

[0111] (a2) Core-shell type styrene acrylic emulsion (3KW-3000 (trade name) manufactured by Taisei Fine Chemical Co., Ltd.). Contains 28.5% by mass of solid content. Particle size is 300 nm, Tg of the core is 20°C, Tg of the shell is 20°C, MFT is 4°C, and in addition to the acrylic styrene polymer, it also contains formic acid, a quaternary ammonium group obtained based on epichlorohydrin and an amino group, and dipropylene glycol monomethyl ether, and also contains products generated by the reaction of components including the polymer component with each other.

[0112] (a3) Acrylic silicone dispersion (KD-20 (trade name) manufactured by Henkel Japan, Ltd.) Contains 20% by mass of solid content, has a particle size of 20 nm, a Tg of 42° C., an MFT of 0° C., and contains a reactive silyl group and a film-forming aid.

[0113] (B) Epoxy resin

[0114] (b1) Bisphenol A type epoxy resin (EM-101-50 (trade name) manufactured by ADEKA Co., Ltd.) Containing 46% by mass of solid content, a particle size of 400 nm, an epoxy equivalent of 1075 g / eq, and containing propylene glycol monomethyl ether and benzyl alcohol.

[0115] (E) Silane coupling agent

[0116] (e1) Epoxy silane coupling agent (KBM-403 (trade name) manufactured by Shin-Etsu Chemical Co., Ltd.) 3-Glycidoxypropyltrimethoxysilane

[0117] (e2) Aminosilane coupling agent (KBM-603 (trade name) manufactured by Shin-Etsu Chemical Co., Ltd.). N-2-(Aminoethyl)-3-aminopropyltrimethoxysilane

[0118] (e3) A reaction product of an epoxysilane coupling agent (KBM-403 (trade name) manufactured by Shin-Etsu Chemical Co., Ltd.) and an aminosilane coupling agent (KBM-603 (trade name) manufactured by Shin-Etsu Chemical Co., Ltd.). (e3) was synthesized as follows. 25 g of 3-glycidoxypropyltrimethoxysilane (KBM-403) and 75 g of N-2-(aminoethyl)-3-aminopropyltrimethoxysilane (KBM-603) were heated and mixed at 50° C. for 72 hours to synthesize (e3).

[0119] (F) Others

[0120] (f1) Defoaming agent (SB630 (trade name) manufactured by Kyoeisha Chemical Co., Ltd.) Emulsion of organic modified polysiloxane and special polymer. Contains 25% by mass of solid content.

[0121] (f2) Film-forming aid (EHG (trade name) manufactured by Nippon Emulsifier Co., Ltd.) Ethylene glycol mono-2-ethylhexyl ether.

[0122] (f3)Water

[0123] The components (A) to (F) were blended in the ratios (parts by mass) shown in Tables 1 and 2 to prepare water-based primer compositions of Examples 1 to 9 and Comparative Examples 1 and 2.

[0124] In the present specification, the solid content refers to the nonvolatile content when measured under the test conditions of 105° C. and 3 hours in accordance with JIS K 6828-1 (Synthetic resin emulsions-Part 1: Method for determining nonvolatile content).

[0125] The simple adhesion (adhesion to mortar (water resistance), joint adhesion (after curing), adhesion to acrylic electrodeposition-coated aluminum (water resistance)) and storage stability of each of the above-mentioned water-based primer compositions were measured and evaluated by the following methods. The results are shown in Tables 1 and 2.

[0126] Simple adhesion (adhesion to mortar (water resistance), joint adhesion (after curing), adhesion to acrylic electrodeposition-coated aluminum (water resistance))

[0127] The simple adhesion was evaluated based on the 2017 edition of the Building Sealing Materials Handbook (published by the Japan Sealing Materials Industry Association).

[0128] The surface of a predetermined adherend (adherends 1 to 3 described below) was cleaned with toluene, and then a predetermined primer (a water-based primer of an example or a comparative example) was applied and dried at room temperature for 60 minutes or more.

[0129] The above adherend and 15 times independent foam polyethylene support material are used to make Figure 1 The test body shown (width 10mm, thickness 8mm, length 150mm). Cast MS2500 NB type (two-component modified silicone sealing material manufactured by Sunstar Giken Co., Ltd.) or PU9000 typeNB (two-component polyurethane sealing material manufactured by Sunstar Giken Co., Ltd.) on the test body. Cured it at 23°C for 1 week, and then cured it at 50°C for 1 week. Furthermore, in the case of water resistance evaluation, after the above-mentioned curing, it was immersed in water at 23°C for 1 week and then left to stand for 24 hours. Then, based on the simple adhesion test in 6.2.1 (2) of the 2017 edition of the Handbook of Building Sealing Materials (published by the Japan Sealing Materials Industry Association), the sealing material was stretched in a 180-degree direction, and the bonding state of the peeled part was visually observed.

[0130] Adherend 1: Mortar (Mortar prepared according to 10.4 of JIS R 5201 using ordinary Portland cement specified in JIS R 5210, manufactured by Engineering Test Services Co., Ltd.) (for evaluation of adhesion (water resistance) to mortar)

[0131] Adhesive 2: Penguin Seal PU9000 typeNB (two-component polyurethane sealant manufactured by Sunstar Giken Co., Ltd.) (used to evaluate joint adhesion (after curing))

[0132] Adherend 3: Acrylic electrodeposition-coated aluminum (manufactured by LIXIL Corporation, acrylic electrodeposition-coated aluminum alloy frame, Autumn Brown) (for evaluation of adhesion (water resistance) to acrylic electrodeposition-coated aluminum)

[0133] The evaluation criteria are as follows.

[0134] ○: The whole is cohesive failure (CF), including some cases where thin cohesive failure (TCF) is mixed.

[0135] ○ / △: Overall, there is a mixture of cohesive failure (CF) and thin layer cohesive failure (TCF).

[0136] △: The whole is TCF.

[0137] ×: Adhesive Failure (AF) was observed.

[0138] Storage stability

[0139] After preparing each water-based primer composition, it was stored at 50° C. for 1 week. Thereafter, the viscosity was measured at 20° C. using a BM type viscometer and a No. 3 spindle at a rotation speed of 30 rpm.

[0140] The evaluation criteria are as follows.

[0141] ○: The viscosity is 4000 mPa·s or less.

[0142] △: The viscosity exceeded 4000 mPa·s, but coating was possible.

[0143] ×: It gelled and could not be applied.

[0144] [Table 1]

[0145]

[0146] [Table 2]

[0147]

[0148] The water-based primer compositions of Examples 1 to 9 were all rated as ×, and exhibited excellent adhesion and storage stability.

[0149] The water-based primer compositions of Comparative Examples 1 and 2 were rated as "×", and were inferior in either adhesion or storage stability.

[0150] Industrial Applicability

[0151] The water-based primer composition of the embodiment of the present invention comprises (A) a copolymer comprising a cationic acrylic polymer and (B) a bisphenol epoxy resin, has excellent adhesion, and can improve water resistance and storage stability. Therefore, the water-based primer composition of the embodiment of the present invention can be suitable for use in architectural adherends.

Claims

1. A water-based primer composition, characterized in that: The aqueous primer composition comprises an organic polymer dispersed in an aqueous medium, the aqueous primer composition comprising: (A) a copolymer comprising a cationic acrylic polymer; (B) Bisphenol type epoxy resin.

2. The water-based primer composition according to claim 1, wherein (A) A part of the copolymer containing a cationic acrylic polymer contains a quaternary ammonium group obtained based on epichlorohydrin and an amino group.

3. The water-based primer composition according to claim 1 or 2, wherein: (A) A part of the copolymer containing a cationic acrylic polymer further contains a reactive silyl group.

4. The water-based primer composition according to claim 1 or 2, wherein: The invention further contains a silane coupling agent, wherein the silane coupling agent includes at least one selected from a silane coupling agent having an amino group and a silane coupling agent having an epoxy group.

5. The aqueous primer composition according to claim 1 or 2, which is neutralized with (C) an acid.

6. The aqueous primer composition for sealing materials according to claim 1 or 2, which is used between a sealing material and an adherend.

7. A method for using a water-based primer composition, wherein: include: Applying the water-based primer composition according to claim 1 or 2 to an adherend to form a primer layer; A sealing material is applied over the primer layer.

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