Primer composition and laminated member

Abstract

Provided is a primer composition excellent in long-term adhesiveness. A primer composition according to the present disclosure contains an acrylic copolymer having a reactive silyl group and a reaction product of an epoxy resin and an amino group-containing alkoxysilane. The number average molecular weight of the acrylic copolymer is 10,000-50,000, and the glass transition temperature of the acrylic copolymer is 40-80°C. The weight ratio of the acrylic copolymer / reaction product is 40 / 60-80 / 20.

Description

Primer composition and laminated member

[0001] The present invention relates to a primer composition and a laminated member.

[0002] Conventionally, in the fields of paints and sealants, primer compositions have been used for purposes such as strengthening the adhesion between various substrates such as metals, resins, and glass and adhesives (for example, Patent Documents 1 and 2).

[0003] In industrial applications, particularly in the bonding of automotive glass, moisture-curing urethane primers are used in combination with urethane adhesives to ensure adhesive reliability. Furthermore, Patent Document 3 discloses a primer composition containing a reaction product of a polysiloxane having two or more epoxy groups in one molecule and an aminosilane, for the purpose of improving adhesion.

[0004] Japanese Unexamined Patent Publication No. 11-209682 Japanese Unexamined Patent Application No. 11-323244 Japanese Unexamined Patent Application No. 2001-323214

[0005] However, the conventional technologies described above had room for further improvement in terms of long-term adhesion. One aspect of the present invention aims to realize a primer composition with excellent long-term adhesion.

[0006] To solve the above problems, a primer composition according to one aspect of the present invention comprises an acrylic copolymer having a reactive silyl group and a reaction product of an epoxy resin and an amino group-containing alkoxysilane, wherein the number average molecular weight of the acrylic copolymer is 10,000 or more and 50,000 or less, the glass transition temperature of the acrylic copolymer is 40°C or more and 80°C or less, and the weight ratio of the acrylic copolymer to the reaction product is 40 / 60 to 80 / 20.

[0007] According to one aspect of the present invention, a primer composition with excellent long-term adhesion properties can be provided.

[0008] One embodiment of the present invention will be described in detail below. (Meth)acrylic means acrylic and / or methacrylic. (Meth)acryloyl group means acryloyl group and / or methacryloyl group. (Meth)acrylamide group means acrylamide group and / or methacrylamide group.

[0009] [1. Primer Composition] A primer composition according to one embodiment of the present invention comprises an acrylic copolymer having a reactive silyl group and a reaction product of an epoxy resin and an amino group-containing alkoxysilane, wherein the number average molecular weight of the acrylic copolymer is 10,000 or more and 50,000 or less, the glass transition temperature of the acrylic copolymer is 40°C or more and 80°C or less, and the weight ratio of the acrylic copolymer to the reaction product is 40 / 60 to 80 / 20.

[0010] In recent years, the widespread adoption of electric vehicles has led to changes in automobile manufacturing processes, and consequently, the requirements for various materials have also changed. For example, automotive glass is now required to be delivered with a primer already applied. In response to this change, primers are now required to not only have adhesive reliability but also to function as a primer for an extended period after application. While conventional primer compositions had room for improvement in long-term adhesion, the inventors, through diligent research, have discovered that by using a specific acrylic copolymer and a reaction product of epoxy resin and amino group-containing alkoxysilane in a specific weight ratio, a primer composition with excellent long-term adhesion can be realized.

[0011] <1-1. Acrylic Copolymer> The primer composition contains an acrylic copolymer having a reactive silyl group. The acrylic copolymer has the reactive silyl group bonded to carbon atoms at the ends of the main chain and / or to the side chains. Therefore, the resulting primer composition has excellent adhesion between the inorganic substrate and the adhesive, as well as excellent storage stability. One type of acrylic copolymer may be used alone, or two or more types may be used in combination.

[0012] In this specification, an acrylic copolymer means a copolymer whose main component is a structural unit derived from an acrylic monomer. The acrylic copolymer preferably contains 50% to 100% by weight of structural units derived from an acrylic monomer, more preferably 70% to 100% by weight, and even more preferably 90% to 100% by weight. The acrylic copolymer may consist solely of structural units derived from an acrylic monomer.

[0013] In this specification, an acrylic monomer is a monomer containing an acrylic radical polymerizable unsaturated group, specifically a (meth)acryloyl group or a (meth)acrylamide group.

[0014] The reactive silyl group is preferably represented by the following general formula (I).

[0015] R ２ ａ | -Si- (OR １ ) ３－ａ (I) In the formula, R １ R is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms. ２ Preferably, is a hydrogen atom or a monovalent hydrocarbon group selected from an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 25 carbon atoms, and an aralkyl group having 7 to 12 carbon atoms, and a is an integer between 0 and 2.

[0016] The average number of reactive silyl groups per molecule of the acrylic copolymer is one or more, preferably three to fifteen, and more preferably three to ten. When the average number of reactive silyl groups is within the above range, the primer formed from the primer composition exhibits superior adhesive strength, durability, and other properties.

[0017] R １ Preferably, the alkyl group is an alkyl group having 1 to 4 carbon atoms, such as a methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, or i-butyl group. If the alkyl group has 10 carbon atoms or less, the reactive silyl group tends to be highly reactive.

[0018] R ２is preferably an alkyl group having 1 to 4 carbon atoms, and more preferably an alkyl group having 1 or 2 carbon atoms, from the viewpoint of excellent curability of the primer composition. R ２ is an aryl group having 6 to 25 carbon atoms, specific examples thereof include a phenyl group. R ２ is an aralkyl group having 7 to 12 carbon atoms, specific examples thereof include a benzyl group.

[0019] From the viewpoint of improving the curability of the acrylic copolymer, a is preferably an integer of 0 or 1. (OR present in general formula (I) １ ) ３－ａ or R ２ ａ has 2 or more groups, two or more R １ or R ２ may each be the same or different.

[0020] The acrylic copolymer preferably comprises a structural unit (a) derived from a monomer containing a reactive silyl group. The monomer containing a reactive silyl group is, for example, a monomer containing, in a molecule thereof, a reactive silyl group represented by general formula (I) bonded to a carbon atom, and is preferably a monomer containing a polymerizable double bond and a reactive silyl group bonded to a carbon atom. Furthermore, the acrylic copolymer may optionally comprise a structural unit derived from a hydroxyl group-containing monomer and / or a structural unit derived from another monomer.

[0021] From the viewpoint of improving curability, the content ratio of the structural unit (a) in the acrylic copolymer is preferably 1% by weight or more based on the total amount of all structural units in the acrylic copolymer, and more preferably 2% by weight or more. In addition, from the viewpoint of improving storage stability, the content ratio of the structural unit (a) in the acrylic copolymer is preferably 30% by weight or less based on the total amount of all structural units in the acrylic copolymer, more preferably 20% by weight or less, and even more preferably 15% by weight or less.

[0022] Examples of the monomer containing a reactive silyl group include a compound represented by the following general formula (II) and a compound represented by the following general formula (III).

[0023] R ３ R ２ ａ | | CH ２ =C-Si-(OR １ ) ３－ａ (II) In general formula (II), R １ , R ２ and a are the same as defined above, and R ３ represents a hydrogen atom or a methyl group.

[0024] R ３ R ２ ａ | | CH ２ =C-COO(CH ２ ) ｎ -Si-(OR １ ) ３－ａ (III) In general formula (III), R １ , R ２ , R ３ and a are the same as defined above, and n represents an integer of 1 or more and 12 or less.

[0025] Examples of the compound represented by general formula (II) include, and the like. Examples of the compound represented by general formula (III) include, and the like.

[0026] Examples of monomers containing hydroxyl groups include hydroxyalkyl esters of (meth)acrylic acid such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 2-hydroxyethyl vinyl ether, N-methylol (meth)acrylamide, 4-hydroxystyrene, Aronics M-5700 from Toagosei Co., Ltd., and Bremmer PP series (polypropylene glycol methacrylate), Bremmer PE series (polyethylene glycol monomethacrylate), Bremmer PEP series (polyethylene glycol polypropylene glycol methacrylate), Bremmer AP-400 (polypropylene glycol monoacrylate), Bremmer AE-350 (polyethylene glycol monoacrylate), and Bremmer GLM (glycerol monomethacrylate) from NOF Corporation; Placcel FA-1, Placcel FA-4, Placcel FM-1, Placcel Examples include ε-caprolactone-modified hydroxyalkyl vinyl copolymer compounds obtained by the reaction of a hydroxyl group-containing compound with ε-caprolactone, such as FM-4 (manufactured by Daicel Corporation) and TONEM-201 (manufactured by DOW Corporation); and polycarbonate-containing vinyl compounds such as HEMAC-1 (manufactured by Daicel Corporation).

[0027] Examples of other monomers include methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, 3,3,5-trimethylcyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, stearyl (meth)acrylate, lauryl (meth)acrylate, benzyl (meth)acrylate, cyclohexyl (meth)acrylate, trifluoroethyl (meth)acrylate, pentafluoropropyl (meth)acrylate, perfluorocyclohexyl (meth)acrylate, (meth)acrylonitrile, glycidyl (meth)acrylate, isobornyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, (meth)acrylamide, α-ethyl (meth)acrylamide, N-butoxymethyl (meth)acrylamide, N,N-dimethyl (meth)acrylamide, N-methyl (meth)acrylamide, (meth)acryloylmorpholine; compounds such as AS-6, AA-6, and AB-6 which are macromonomers (all manufactured by Toagosei Co., Ltd.); phosphate ester group-containing (meth)acrylic compounds such as condensation products of hydroxyalkyl esters of (meth)acrylic acid with phosphoric acid or phosphate esters; monomers free of silyl groups and hydroxyl groups, such as (meth)acrylates containing urethane bonds and / or siloxane bonds; and styrene.

[0028] The number average molecular weight of the acrylic copolymer is 10,000 or more and 50,000 or less. From the viewpoint of improving the adhesiveness of a primer composition containing the acrylic copolymer, the number average molecular weight of the acrylic copolymer is more preferably 20,000 or more, and further preferably 25,000 or more. The number average molecular weight of the acrylic copolymer is preferably 45,000 or less, may be 40,000 or less, and may be 35,000 or less. In the present specification, the number average molecular weight means a value measured by gel permeation chromatography (GPC) and calculated in terms of polystyrene.

[0029] The glass transition temperature of the acrylic copolymer is 40°C or higher and 80°C or lower. Preferably, the glass transition temperature of the acrylic copolymer is 40°C or higher and 75°C or lower, more preferably 40°C or higher and 70°C or lower, and particularly preferably 50°C or higher and 70°C or lower. The glass transition temperature may also be 40°C or higher and 60°C or 50°C or higher and 60°C or lower. In this specification, Tg of the acrylic copolymer means the value obtained by Fox's formula (TG Fox, Bull. Am. Phys. Soc. 1, 123 (1956)).

[0030] From the viewpoint of improving adhesion, the primer composition preferably contains 1% to 30% by weight of the acrylic copolymer, and more preferably 2% to 25% by weight, based on 100% by weight of the total amount of the primer composition. In one embodiment, the primer composition may contain 10% or more by weight of the acrylic copolymer, and may contain 15% or more by weight, based on 100% by weight of the total amount of the primer composition. Furthermore, from the viewpoint of improving storage stability, the primer composition preferably contains 30% or less by weight of the acrylic copolymer, and more preferably 25% or less by weight. In one embodiment, the primer composition contains 1% to 30% by weight of the acrylic copolymer, based on 100% by weight of the total amount of the primer composition. In one embodiment, the primer composition may contain 10% to 30% by weight of the acrylic copolymer, based on 100% by weight of the total amount of the primer composition.

[0031] <1-2. Reaction product of epoxy resin and amino group-containing alkoxysilane> The primer composition contains a reaction product of epoxy resin and amino group-containing alkoxysilane. In this specification, the reaction product of epoxy resin and amino group-containing alkoxysilane is also simply referred to as the reaction product. The reaction product can be obtained by reacting the epoxy resin and amino group-containing alkoxysilane, for example, at a temperature of 70°C to 90°C for 2 to 4 hours under a nitrogen atmosphere.

[0032] The epoxy resin is not particularly limited, but examples include bisphenol A type epoxy resin, bisphenol F type epoxy resin, novolac type epoxy resin, glycidyl ester type epoxy resin, hydrogenated bisphenol A (or F) type epoxy resin, glycidyl ether type epoxy resin, aminoglycidyl ether resin, and epoxy compounds obtained by adding bisphenol A (or F) compounds, polybasic acids, etc. to these epoxy resins. In other words, it is desirable that the epoxy resin contains one or more selected from the group consisting of bisphenol A type epoxy resin, bisphenol F type epoxy resin, novolac type epoxy resin, glycidyl ester type epoxy resin, hydrogenated bisphenol A type epoxy resin, hydrogenated bisphenol F type epoxy resin, glycidyl ether type epoxy resin, aminoglycidyl ether resin, and epoxy compounds obtained by adding bisphenol A compounds, bisphenol F compounds, or polybasic acids to these epoxy resins.

[0033] The amino group-containing alkoxysilane is not particularly limited, but examples include bis(trimethoxysilylpropyl)amine, bis(triethoxysilylpropyl)amine, γ-aminopropyltrimethoxysilane, γ-aminopropylmethyldimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropylethyldiethoxysilane, N-β-aminoethyl-γ-aminopropyltrimethoxysilane, N-β-aminoethyl-γ-aminopropylmethyldimethoxysilane, N-β-aminoethyl-γ-aminopropyltriethoxysilane, N-β-aminoethyl-γ-aminopropylethyldiethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, and (2-aminoethyl)aminomethyltrimethoxysilane.

[0034] From the viewpoint of long-term adhesion, the weight ratio of the acrylic copolymer to the reaction product is preferably 40 / 60 to 80 / 20, more preferably 45 / 55 to 75 / 25, more preferably 45 / 55 to 70 / 30, even more preferably 45 / 55 to 60 / 40, and particularly preferably 45 / 55 to 50 / 50. In one embodiment, the weight ratio may be 40 / 60 to 60 / 40, or 40 / 60 to 50 / 50. Alternatively, in one embodiment, the weight ratio may be 50 / 50 to 70 / 30.

[0035] <1-3. Other Components> The primer composition may also contain other components, such as additives commonly used in the art, to the extent that they provide the effects of the present invention. Examples of such additives include organotin catalysts, retarders, dehydrating agents, diluent solvents, fillers, flame retardants, dispersants, defoamers, plasticizers, tackifiers, thixotropes, antioxidants, light stabilizers, UV absorbers, hydrolysis stabilizers, titanate coupling agents, aluminate coupling agents, antistatic agents, and low-shrinkage agents. The composition may contain only one additive or two or more additives. The amounts of these additives can be appropriately determined by those skilled in the art depending on their intended use.

[0036] (Organotin Catalyst) The organotin catalyst is a silanol condensation catalyst for curing acrylic copolymers having reactive silyl groups. Specifically, the silanol condensation catalyst is a catalyst that promotes the hydrolysis and condensation of the reactive silyl groups in the acrylic copolymer, thereby extending the chain or crosslinking the acrylic copolymer. By including the organotin catalyst in the primer composition, the primer curing time can be shortened and the adhesion between the inorganic substrate and the adhesive can be improved.

[0037] Specific examples of organotin catalysts include dibutyltin compounds such as dibutyltin dilaurate, dibutyltin dioctanoate, dibutyltin bis(butylmaleate), dibutyltin diacetate, dibutyltin oxide, and dibutylbis(2,4-pentanedionato)tin(IV); dioctyltin compounds such as dioctyltin bis(acetylacetonate), dioctyltin dilaurate, dioctyltin distearate, dioctyltin diacetate, and dioctyltin oxide; reaction products of dibutyltin oxide and silicate compounds, reaction products of dioctyltin oxide and silicate compounds, and reaction products of dibutyltin oxide and phthalate esters. From the viewpoint of improving initial adhesion to inorganic substrates, organotin catalysts preferably have a β-dicarbonyl structure.

[0038] The primer composition can shorten the primer curing time and improve the adhesion between the inorganic substrate and the adhesive, and therefore preferably contains 0.05 parts by weight or more, more preferably 0.1 parts by weight or more, and even more preferably 0.5 parts by weight or more, of the organotin catalyst per 100 parts by weight of the acrylic copolymer. Furthermore, from the viewpoint of workability, the primer composition preferably contains 10 parts by weight or less, more preferably 5 parts by weight or less, and even more preferably 3 parts by weight or less, of the organotin catalyst per 100 parts by weight of the acrylic copolymer.

[0039] (Retinder) The retarder prevents the hydrolysis and condensation reactions of the reactive silyl groups in the acrylic copolymer by the organotin catalyst during storage of the primer composition. Examples of retarders include mercapto compounds and / or β-dicarbonyl compounds. By including a retarder in the primer composition, storage stability can be improved, for example, by reducing the catalytic activity of the organotin catalyst through ligand exchange or by delaying the dehydration condensation between Si and OH groups contained in the mercapto compound.

[0040] Examples of mercapto compounds include n-dodecyl mercaptan (nDM), t-dodecyl mercaptan, n-butyl mercaptan, γ-mercaptopropyltrimethoxysilane, and γ-mercaptopropyltriethoxysilane.

[0041] A β-dicarbonyl compound is a compound having a structure in which two carbonyl groups are bonded to one carbon atom. While not particularly limited, examples of β-dicarbonyl compounds include ethyl acetate, acetyl acetonate, methyl acetate, and dimethyl malonate.

[0042] From the viewpoint of improving storage stability, the primer composition preferably contains 0.05 parts by weight or more of a retarder per 100 parts by weight of the acrylic copolymer, more preferably 0.1 parts by weight or more, and even more preferably 0.5 parts by weight or more. Furthermore, from the viewpoint of curability, the primer composition preferably contains 10 parts by weight or less of a retarder per 100 parts by weight of the acrylic copolymer, more preferably 5 parts by weight or less, and even more preferably 3 parts by weight or less.

[0043] (Dehydrating agent) When moisture is present, the hydrolysis reaction of the reactive silyl groups in the acrylic copolymer proceeds. Therefore, by including a dehydrating agent in the primer composition, this hydrolysis reaction can be prevented and storage stability can be improved.

[0044] Examples of dehydrating agents include hydrolyzable ester compounds such as tosyl isocyanate, methyl orthoformate, ethyl orthoformate, methyl orthoacetate, ethyl orthoacetate, trimethyl orthopropionate, triethyl orthopropionate, trimethyl orthoisopropionate, triethyl orthoisopropionate, trimethyl orthobutyrate, triethyl orthobutyrate, trimethyl orthoisobutyrate, and triethyl orthoisobutyrate. Among these, methyl orthoacetate is preferred in terms of its dehydrating effect. These may be used alone or in combination of two or more.

[0045] From the viewpoint of improving storage stability, the primer composition preferably contains 0.1 parts by weight or more of a dehydrating agent per 100 parts by weight of the acrylic copolymer, more preferably 1.0 part by weight or more, and even more preferably 3.0 parts by weight or more. Furthermore, from the viewpoint of adhesion, the primer composition preferably contains 30 parts by weight or less of a dehydrating agent per 100 parts by weight of the acrylic copolymer, more preferably 20 parts by weight or less, and even more preferably 10 parts by weight or less.

[0046] (Diluting Solvent) The diluting solvent is not particularly limited, but aliphatic hydrocarbons, aromatic hydrocarbons, alicyclic hydrocarbons, halogenated hydrocarbons, alcohols, esters, ketones, ethers, etc., can be used. The diluting solvent is especially preferably a polar solvent with a low boiling point and fast drying time, such as butyl acetate, ethyl acetate, and methyl ethyl ketone. By adding the diluting solvent to the primer composition, the drying time of the primer composition is shortened, and the process time until adhesive application can be reduced. The diluting solvent may be used alone or in combination of two or more types.

[0047] If the primer composition contains a diluent, the content of the diluent in the primer composition is preferably, from the viewpoint of improving adhesion, 60% to 95% by weight, 70% to 95% by weight, and more preferably 80% to 95% by weight, based on 100% by weight of the total amount of the primer composition.

[0048] (Fillers) Fillers are not particularly limited, but examples include reinforcing fillers such as fumed silica, precipitated silica, crystalline silica, fused silica, dolomite, anhydrous silicic acid, hydrated silicic acid, and carbon black; powdered fillers such as heavy calcium carbonate, colloidal calcium carbonate, magnesium carbonate, barium carbonate, barium sulfate, diatomaceous earth, calcined clay, clay, talc, barite, anhydrous gypsum, titanium dioxide, bentonite, organic bentonite, ferric oxide, aluminum fine powder, flint powder, zinc oxide, activated zinc oxide, mica, zinc oxide, lead white, lithopone, zinc sulfide, shirasu balloons, glass microballoons, organic microballoons made of phenolic resin or vinylidene chloride resin, PVC powder, PMMA powder, etc.; and fibrous fillers such as asbestos, glass fibers, and filaments. In addition to the above, coloring pigments such as titanium dioxide, lead chromate, chromium oxide, ultramarine, cobalt blue, cyanine blue, cyanine green, lake red, and quinacridone red can also be used.

[0049] The content of the filler in the primer composition is preferably, for example, 1.0% to 50% by weight, 5.0% to 40% by weight, and more preferably 10% to 30% by weight, based on 100% by weight of the total amount of the primer composition.

[0050] (Flame retardants) Flame retardants are not particularly limited, but examples include ammonium polyphosphate, phosphorus-based plasticizers such as tricresyl phosphate, aluminum hydroxide, magnesium hydroxide, and thermally expandable graphite. These flame retardants may be used individually or in combination of two or more.

[0051] A wide range of conventionally known ammonium polyphosphates can be used as the aforementioned ammonium polyphosphate. Among these, from the viewpoint of water resistance, surface-treated ammonium polyphosphates such as ammonium polyphosphate coated with resin and microencapsulated, or surface-modified ammonium polyphosphate, are preferred, and those whose surface is coated with melamine formaldehyde resin are even more preferred.

[0052] The flame retardant content in the primer composition is preferably, for example, 0.1% to 10% by weight, more preferably 0.5% to 5.0% by weight, and more preferably 1.0% to 4.0% by weight, based on 100% by weight of the total amount of the primer composition.

[0053] (Dispersant) The primer composition may also contain a dispersant. As a dispersant, a pigment dispersion paste obtained by mixing and dispersing a pigment and a dispersant according to a known method may be used. Commercially available dispersants may also be used. For example, ANTI-TERRA®-U, ANTI-TERRA®-U100, ANTI-TERRA®-204, ANTI-TERRA®-205, DISPERBYK®-101, DISPERBYK®-102, DISPERBYK®-103, DISPERBYK®-106, DISPERBYK®-108, DISPERBYK®-109, DISPERBYK® Trademark) -110, DISPERBYK (Registered Trademark) -111, DISPERBYK (Registered Trademark) -112, DISPERBYK (Registered Trademark) -116, DISPERBYK (Registered Trademark) -130, DISPERBYK (Registered Trademark) -140, DISPERBYK (Registered Trademark) -142, DISPERBYK (Registered Trademark) -145, DISPERBYK (Registered Trademark) -161, DISPERBYK (Registered Trademark) -162, DISPERBYK (Registered Trademark) -163, DISPERBYK (Registered Trademark) Registered Trademark) -164, DISPERBYK (Registered Trademark) -166, DISPERBYK (Registered Trademark) -167, DISPERBYK (Registered Trademark) -168, DISPERBYK (Registered Trademark) -170, DISPERBYK (Registered Trademark) -171, DISPERBYK (Registered Trademark) -174, DISPERBYK (Registered Trademark) -180, DISPERBYK (Registered Trademark) -182, DISPERBYK (Registered Trademark) -183, DISPERBYK (Registered Trademark) -184, DISPERBYK ( Registered Trademark) - 185, DISPERBYK (Registered Trademark) - 2000, DISPERBYK (Registered Trademark) - 2001, DISPERBYK (Registered Trademark) - 2008, DISPERBYK (Registered Trademark) - 2009, DISPERBYK (Registered Trademark) - 2022, DISPERBYK (Registered Trademark) - 2025, DISPERBYK (Registered Trademark) - 2050, DISPERBYK (Registered Trademark) - 2070, DISPERBYK (Registered Trademark) - 2096, DISPERBYK (Registered Trademark) - 2150,DISPERBYK(registered trademark)-2155, DISPERBYK(registered trademark)-2163, DISPERBYK(registered trademark)-2164, BYK(registered trademark)-P104, BYK(registered trademark)-P104S, BYK(registered trademark)-P105, BYK(registered trademark)-9076, BYK(registered trademark)-9077, BYK(registered trademark)-220S, ANTI-TERRA(registered trademark)-250, DISPERBYK(registered trademark)-187, DISPERBYK(registered trademark)-190, DISPERBYK(registered trademark)-191, DISP ERBYK®-192, DISPERBYK®-193, DISPERBYK®-194, DISPERBYK®-198, DISPERBYK®-2010, DISPERBYK®-2012, DISPERBYK®-2013, DISPERBYK®-2015, DISPERBYK®-2090, DISPERBYK®-2091, DISPERBYK®-2095 (all manufactured by Bic Chemie), DIS PARLON® 2150, DISPARLON® KS-860, DISPARLON® KS-873N, DISPARLON® 7004, DISPARLON® 1831, DISPARLON® 1850, DISPARLON® 1860, DISPARLON® DA-1401, DISPARLON® PW-36, DISPARLON® DA-1200, DISPARLON® DA-550, DISPARLON Examples include (Registered Trademark) DA-703-50, DISPARLON (Registered Trademark) DA-7301, DISPARLON (Registered Trademark) DN-900, DISPARLON (Registered Trademark) DA-325, DISPARLON (Registered Trademark) DA-375, DISPARLON (Registered Trademark) DA-234 (all manufactured by Kusumoto Kasei Co., Ltd.), EFKA APOLYMER 4550 (manufactured by EFKA Corporation), Solspers (Registered Trademark) 27000, Solspers (Registered Trademark) 41000, Solspers (Registered Trademark) 53095 (all manufactured by Abyssia Corporation), etc.

[0054] The number-average molecular weight of the dispersant is preferably 1,000 to 100,000, preferably 2,000 to 50,000, and more preferably 4,000 to 50,000. If the number-average molecular weight of the dispersant is 1,000 or more, sufficient dispersion stability can be obtained, and if it is 100,000 or less, there is no risk of the composition becoming too viscous, resulting in a composition with excellent handling properties.

[0055] The content of the dispersant in the primer composition is preferably, for example, 0.1% by weight or more and 10% by weight or less, and more preferably 0.3% by weight or more and 5.0% by weight or less, and more preferably 0.5% by weight or more and 3.0% by weight or less, based on 100% by weight of the total amount of the primer composition.

[0056] (Tackifier) ​​The tackifier is not particularly limited and can be any tackifier that is commonly used at room temperature, whether solid or liquid. Specifically, examples include styrene-based block copolymers such as styrene-butadiene-styrene block copolymer (SBS), styrene-isoprene-styrene block copolymer (SIS), styrene-ethylenebutylene-styrene block copolymer (SEBS), styrene-ethylenepropylene-styrene block copolymer (SEPS), and styrene-isobutylene-styrene block copolymer (SIBS), as well as their hydrogenated derivatives, phenol resins, modified phenol resins (e.g., cashew oil-modified phenol resin, tall oil-modified phenol resin, etc.), terpene phenol resins, xylene-phenol resins, cyclopentadiene-phenol resins, coumarone indene resins, rosin-based resins, rosin ester resins, hydrogenated rosin ester resins, xylene resins, low molecular weight polystyrene-based resins, styrene copolymer resins, petroleum resins (e.g., C5 hydrocarbon resins, C9 hydrocarbon resins, C5C9 hydrocarbon copolymer resins, etc.), hydrogenated petroleum resins, terpene-based resins, DCPD resins, etc. The above-mentioned tackifiers may be used individually or in combination of two or more types.

[0057] The content of the tackifier in the primer composition is preferably, for example, 0.1% to 10% by weight, more preferably 0.3% to 5.0% by weight, and more preferably 0.5% to 3.0% by weight, based on 100% by weight of the total amount of the primer composition.

[0058] (Thixotropic Agents) There are no particular limitations on thixotropic agents (anti-sagging agents), but examples include polyamide waxes; hydrogenated castor oil derivatives; and metal soaps such as calcium stearate, aluminum stearate, and barium stearate. The fumed silica mentioned above as a filler can also be used as a thixotropic agent. Furthermore, using rubber powder with a particle size of 10 μm to 500 μm, as described in Japanese Patent Publication No. 11-349916, or organic fibers, as described in Japanese Patent Publication No. 2003-155389, can yield a composition with high thixotropy and good workability. These thixotropic agents may be used individually or in combination of two or more.

[0059] The content of the thixotropic agent in the primer composition is preferably 0.1% to 5.0% by weight, more preferably 0.2% to 4.0% by weight, and more preferably 0.3% to 3.0% by weight, based on 100% by weight of the total amount of the primer composition.

[0060] (Antioxidant) When the primer composition contains an antioxidant (anti-aging agent), the heat resistance of the resulting cured product can be improved. The antioxidant is not particularly limited, but examples include hindered phenol, monophenol, bisphenol, and polyphenol antioxidants. Among these, hindered phenol antioxidants are preferred. As antioxidants, hindered amine-based photostabilizers such as Chinuvin® 622LD, Chinuvin® 144, CHIMASSORB® 944LD, and CHIMASSORB® 119FL (all manufactured by Ciba Specialty Chemicals Co., Ltd.); MARK LA-57, MARK LA-62, MARK LA-67, MARK LA-63, and MARK LA-68 (all manufactured by ADEKA Corporation); and Sanol® LS-770, Sanol® LS-765, Sanol® LS-292, Sanol® LS-2626, Sanol® LS-1114, and Sanol® LS-744 (all manufactured by Sankyo Co., Ltd.) can also be used.

[0061] The antioxidant content in the primer composition is preferably, for example, 0.1% to 5.0% by weight, more preferably 0.3% to 4.0% by weight, and more preferably 0.5% to 3.0% by weight, based on 100% by weight of the total amount of the primer composition.

[0062] (Photostabilizer) When the primer composition contains a photostabilizer, photo-oxidative degradation of the resulting cured product can be prevented. The photostabilizer is not particularly limited, but examples include benzotriazole compounds, hindered amine compounds, and benzoate compounds. Among these, hindered amine compounds are preferred. In particular, a tertiary amine-containing hindered amine photostabilizer is preferred because it can improve the storage stability of the primer composition. Examples of tertiary amine-containing hindered amine-based light stabilizers include, more specifically, Chinuvin® 622LD, Chinuvin® 144, and Chimasorb® 119FL (all manufactured by BASF); MARK LA-57, LA-62, LA-67, and LA-63 (all manufactured by ADEKA Corporation); and Sanol® LS-765, LS-292, LS-2626, LS-1114, and LS-744 (all manufactured by Sankyo Co., Ltd.).

[0063] The content of the photostabilizer in the primer composition is preferably, for example, 0.1% by weight or more and 5.0% by weight or less, more preferably 0.3% by weight or more and 4.0% by weight or less, and more preferably 0.5% by weight or more and 3.0% by weight or less, based on 100% by weight of the total amount of the primer composition.

[0064] (UV absorber) When the primer composition contains a UV absorber, the surface weather resistance of the resulting cured product can be improved. The UV absorber is not particularly limited, but examples include benzophenone compounds, benzotriazole compounds, salicylate compounds, substituted tolyl compounds, and metal chelate compounds, with benzotriazole compounds being particularly preferred.

[0065] The amount of ultraviolet absorber in the primer composition is preferably 0.1% to 5.0% by weight, more preferably 0.3% to 4.0% by weight, and more preferably 0.5% to 3.0% by weight, based on 100% by weight of the total amount of the primer composition.

[0066] (Moisture) The primer composition may contain moisture derived from the above components and other components. If the primer composition contains moisture, the storage stability of the primer composition may be impaired. Therefore, the moisture content in the primer composition is preferably 0.3% by weight or less, more preferably 0.2% by weight or less, and more preferably 0.1% by weight or less, based on 100% by weight of the total amount of the primer composition. The lower limit is not particularly limited and may be 0% by weight.

[0067] [2. Uses of the Primer Composition] The primer composition can be used as a primer composition for adhesives for inorganic substrates. Examples of inorganic substrates include mortar, metal, ceramics, glass, cement, and ceramic molded products. The primer composition can be used as a primer for modified silicone adhesives and urethane adhesives. It can also be used as a primer for the direct glazing (DG) method, which can be used on both glass surfaces and body surfaces.

[0068] One embodiment of the present invention also includes a laminated member comprising a substrate, a primer layer laminated on the substrate and formed from the above-described primer composition, and an adhesive layer laminated on the primer layer. The laminated member can also be described as a laminated member in which the primer layer and the adhesive layer are bonded together on the substrate. The substrate is the inorganic substrate described above.

[0069] The laminated member can be obtained by applying a primer composition onto a substrate to form a primer layer, and then applying an adhesive on the primer layer to form an adhesive layer. In other words, the method for manufacturing a laminated member according to one embodiment of the present invention preferably includes a primer layer formation step and an adhesive lamination step.

[0070] In the primer layer formation step, the primer composition described above is applied to the substrate to form a primer layer. In the primer layer formation step, it is preferable to dry the primer composition after applying it to the substrate to pre-cur it. Pre-curing means that the surface of the primer layer formed by applying the primer composition hardens, and when the adhesive is applied to the primer layer in the adhesive lamination step, the primer composition and the adhesive do not mix, maintaining a two-layer structure.

[0071] From the viewpoint of adhesion, the drying time is preferably 10 minutes or more, more preferably 20 minutes or more, and even more preferably 30 minutes or more.

[0072] From the viewpoint of adhesion, the drying temperature is preferably 5°C or higher, more preferably 10°C or higher, and even more preferably 20°C or higher. Furthermore, from the viewpoint of adhesion, the drying temperature is preferably 60°C or lower, more preferably 45°C or lower, and even more preferably 30°C or lower.

[0073] In the adhesive lamination process, an adhesive is applied to the primer layer to form an adhesive layer, thereby obtaining a laminated member in which the primer layer and the adhesive layer are bonded together. As described above, in the adhesive lamination process, it is preferable to apply the adhesive after the primer layer has dried and partially cured to form the adhesive layer. Even if the adhesive is applied after the primer layer has partially cured, the adhesion between the primer layer and the adhesive layer is maintained. This is presumed to be because unreacted functional groups in the primer layer and the adhesive layer react at the interface between the primer layer and the adhesive layer.

[0074] The present invention is not limited to the embodiments described above, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention.

[0075] One embodiment of the present invention may include the following configurations: <1> A primer composition comprising an acrylic copolymer having reactive silyl groups and a reaction product of an epoxy resin and an amino group-containing alkoxysilane, wherein the number average molecular weight of the acrylic copolymer is 10,000 or more and 50,000 or less, the glass transition temperature of the acrylic copolymer is 40°C or more and 80°C or less, and the weight ratio of the acrylic copolymer to the reaction product is 40 / 60 to 80 / 20. <2> The primer composition according to <1>, wherein the average number of reactive silyl groups per molecule of the acrylic copolymer is 3 or more and 15 or less. <3> The primer composition according to <1> or <2>, comprising 1% or more by weight and 30% by weight of the acrylic copolymer per 100% by weight of the primer composition. <4> A laminated member comprising a substrate, a primer layer laminated on the substrate and formed from any one of the primer compositions according to <1> to <3>, and an adhesive layer laminated on the primer layer.

[0076] The present invention will be described in more detail below based on examples, but the present invention is not limited to these examples.

[0077] [Materials] The following materials were used in the examples and comparative examples.

[0078] <Raw materials for acrylic copolymers> Styrene (abbreviated as "St", manufactured by Kishida Chemical Co., Ltd.) n-butyl acrylate (abbreviated as "BA", manufactured by Nippon Shokubai Co., Ltd.) Methyl methacrylate (abbreviated as "MMA", manufactured by Mitsubishi Chemical Corporation) Stearyl methacrylate (abbreviated as "SMA", manufactured by NOF Corporation as "Bremmer SMA") γ-methacryloxypropyltrimethoxysilane (abbreviated as "TSMA", manufactured by Momentive Performance Materials Japan LLC as "A-174") Acrylamide (abbreviated as "AM") (manufactured by Tokyo Chemical Industry Co., Ltd. as "Acrylamide Monomer") 2,2'-azobis(2-methylbutyronitrile) (abbreviated as "V-59") (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd. as "V-59") <Raw materials for reaction products of epoxy resin and amino group-containing alkoxysilane> Epoxy resin ("jER828" manufactured by Mitsubishi Chemical Corporation) γ-aminopropyltriethoxysilane ("A-1100" manufactured by Momentive Performance Materials Japan LLC) <Polyisocyanate compound> Hexamethylene diisocyanate polymer ("Coronate® HX" manufactured by Tosoh Corporation) <Silane coupling agent> γ-glycidoxypropyltrimethoxysilane ("A-187" manufactured by Momentive Performance Materials Japan LLC) Bis[3-(trimethoxysilylpropyl)]amine ("A-1170" manufactured by Momentive Performance Materials Japan LLC) <Dehydrating agent> Methyl orthoacetate (abbreviated as "MOA", manufactured by Nippo Chemical Co., Ltd.) <Organotin catalyst> Neostan U-220H (manufactured by Nitto Kasei Co., Ltd.) <Mercapto compound (retardant)> n-dodecyl mercaptan (abbreviated as "nDM", manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) <Diluting solvent> Butyl acetate (abbreviated as "BuAc", manufactured by KH Neochem Co., Ltd.) Ethyl acetate (abbreviated as "EtAc", manufactured by KH Neochem Co., Ltd.) [Measurement and evaluation method] Measurement and evaluation in the examples and comparative examples were carried out by the following method.

[0079] <Molecular Weight Measurement> The number-average molecular weight (Mn) of the acrylic copolymer was measured using a high-speed GPC instrument HLC-8320GPC manufactured by Tosoh Corporation and calculated in polystyrene equivalent. For the measurement, TSKgel superH5000, TSKgel superH4000, TSKgel superH3000, and TSKgel guardcolumn SuperH-L were used as columns, and THF (tetrahydrofuran) was used as the mobile phase. The measurement temperature was 40°C and the flow rate was 0.6 ml / min.

[0080] <Glass Transition Temperature> The Tg of the acrylic copolymer was calculated using Fox's formula.

[0081] <Number of Si atoms per molecule> In this specification, the value representing the average number of reactive silyl groups per molecule of an acrylic copolymer is also referred to as the "number of Si atoms per molecule." The number of Si atoms per molecule can be calculated from (number-average molecular weight) / (Si equivalent). Here, the Si equivalent can be calculated from the amounts of each component shown in Table 1.

[0082] <SP Value> The SP value is δ, calculated using the following formula based on the method described by Fedors [Robert F. Fedors, Polymer Engineering and Science, 14, 147-154 (1974)]. Fedors' formula: δ = (ΣΔei / ΣΔvi) １／２ In the formula, Δei represents the evaporation energy (cal / mol) of an atom or group of atoms, and Δvi represents the molar volume (cm³). ３ It indicates ( / mol). The unit of SP value is (cal / cm). ３ ) １／２ That is the case.

[0083] <Adhesion Test> - Specimen Preparation (for Short-Term Adhesion Evaluation) The primer compositions obtained in the Examples and Comparative Examples were applied to a glass substrate using a brush and cured for 4 hours at 23°C and 50% relative humidity. Then, urethane adhesive was applied in a bead on the resulting primer layer to be 10 mm (height) x 10 mm to 15 mm (width) x 100 mm (length). The applied adhesive bead was compressed to a height of approximately 6 mm to prepare a test specimen. SikaTack® Ultrafast (manufactured by Sika Corporation Japan) was used as the urethane adhesive.

[0084] - Specimen preparation (for long-term adhesion evaluation): Specimens were prepared in the same manner as for short-term adhesion evaluation, except that the primer composition was cured for 168 hours at 60°C and 50% relative humidity.

[0085] • Test Example 1 (Primary Evaluation: Room Temperature Adhesion) The prepared test specimens were cured for 7 days at 23°C and 50% relative humidity. Then, an incision of about 1 cm was made with a utility knife at the interface between the urethane adhesive and the substrate, and the specimens were peeled off at a 90° angle. After peeling off about 10 mm, an incision was made with a utility knife at the interface between the peeled adhesive bead and the substrate, and the peeling process was continued. The adhesion was evaluated according to the percentage of the test specimens that had their adhesive beads peeled off.

[0086] • Test Example 2 (Secondary Evaluation: PV1200 Test) The prepared test specimens were cured for 7 days at 23°C and 50% relative humidity. Then, the following (1) to (5) were repeated 20 times, each time the specimens were exposed to the respective temperatures and / or humidity levels.

[0087] (1) The test specimen is heated and humidified from 23°C and 50% relative humidity to 80°C and 80% relative humidity over a period of 60 minutes.

[0088] (2) After reaching 80°C and 80% relative humidity, maintain this temperature for 240 minutes.

[0089] (3) Cool to -40°C over 120 minutes.

[0090] (4) After reaching -40°C, maintain the temperature for 240 minutes.

[0091] (5) Heat to 23°C over 60 minutes. After 20 cycles, the adhesive bead was removed in the same manner as in Test Example 1, and the adhesion was evaluated according to the percentage of fractured specimens from which the adhesive bead had been removed.

[0092] [Production Examples] <Acrylic Copolymer> ・Production Example 1 46.3 parts by weight of butyl acetate was charged into a reaction vessel equipped with a stirrer, thermometer, reflux condenser, nitrogen gas inlet tube, and dropping funnel, and the temperature was raised to 110°C while introducing nitrogen gas. Then, a mixture consisting of 2.0 parts by weight of styrene, 6.6 parts by weight of γ-methacryloxypropyltrimethoxysilane, 14.0 parts by weight of stearyl methacrylate, 71.1 parts by weight of methyl methacrylate, 5.3 parts by weight of n-butyl acrylate, 1.0 part by weight of acrylamide, 18 parts by weight of butyl acetate, and 0.84 parts by weight of 2,2'-azobis(2-methylbutyronitrile) was added dropwise at a constant rate over 5 hours using a dropping funnel. After the dropwise addition was complete, 0.1 parts by weight of 2,2'-azobis(2-methylbutyronitrile) and 9 parts by weight of butyl acetate were added dropwise at a constant rate over 1 hour, and then the mixture was aged at 110°C for 2 hours before being cooled. Butyl acetate, orthoacetic acid, and dimethyl adipate were added to the obtained resin solution to obtain an acrylic copolymer with a resin solids content of 40% by weight. The number-average molecular weight of the obtained acrylic copolymer was 19,000. The calculated glass transition temperature was 48°C.

[0093] - Production Examples 2 to 5 and 7 to 9: Acrylic copolymers were obtained using the same procedure as in Production Example 1, except that the amounts of monomers and initiators were changed as shown in Table 1.

[0094] <Reaction product of epoxy resin and amino group-containing alkoxysilane> - Production example 6 (reaction product of jER828 and A-1100) jER828 and A-1100 were mixed in a molar ratio of 1:1 and reacted at 70°C for 4 hours under a nitrogen atmosphere to obtain a reaction product of epoxy resin and amino group-containing alkoxysilane.

[0095] [Examples] Primer compositions were prepared by blending each component according to the composition shown in Table 2.

[0096] Example 1: An acrylic copolymer was diluted with a diluent solvent, then a dehydrating agent was added, and the mixture was stirred for 60 minutes to promote dehydration. Subsequently, a catalyst, a retarder, and the reaction product of the epoxy resin and the amino group-containing alkoxysilane were added to obtain a primer composition.

[0097] Examples 2 to 13 and Comparative Examples 1 to 4: Primer compositions were prepared using the same procedure as in Example 1, except that the amounts of each component were changed as shown in Tables 2 to 4. The adhesion properties of the obtained primer compositions were evaluated.

[0098] [Evaluation Results] The compositions and evaluation results of the examples and comparative examples are shown in Tables 2 to 4.

[0099] In the adhesion evaluation results in Tables 2 to 4, CF represents cohesive failure of the adhesive, PS represents interfacial failure between the adhesive and primer, and AF represents interfacial failure between the substrate and primer. The numbers represent the proportions of these. A higher proportion of CF indicates better adhesion. In Comparative Example 3, the adhesion was insufficient in the primary evaluation of short-term and long-term adhesion, so a secondary evaluation was not performed.

[0100] Examples 1 to 13 include an acrylic copolymer having a number average molecular weight of 10,000 to 50,000 and a glass transition temperature of 40°C to 80°C, in addition to a reaction product of an epoxy resin and an amino group-containing alkoxysilane, with a weight ratio of the acrylic copolymer to the reaction product ranging from 40 / 60 to 80 / 20. In contrast, Comparative Example 1 includes only the acrylic copolymer of Production Example 5, which has a glass transition temperature below 40°C, as the acrylic copolymer. Comparative Examples 2 and 3 have a weight ratio of acrylic copolymer to the reaction product outside the range of 40 / 60 to 80 / 20. Comparative Example 4 includes a polyisocyanate compound instead of the reaction product of the epoxy resin and the amino group-containing alkoxysilane.

[0101] While some comparative examples showed similar short-term adhesion to the examples, Examples 1 to 13 demonstrated superior long-term adhesion compared to Comparative Examples 1 to 4, particularly in secondary evaluation.

[0102] One aspect of the present invention can be suitably used for bonding using adhesives.

Claims

1. A primer composition comprising an acrylic copolymer having a reactive silyl group, and a reaction product of an epoxy resin and an amino group-containing alkoxysilane, wherein the number average molecular weight of the acrylic copolymer is 10,000 or more and 50,000 or less, the glass transition temperature of the acrylic copolymer is 40°C or more and 80°C or less, and the weight ratio of the acrylic copolymer to the reaction product is 40 / 60 to 80 / 20.

2. The primer composition according to claim 1, wherein the average number of reactive silyl groups per molecule of the acrylic copolymer is 3 or more and 15 or less.

3. The primer composition according to claim 1, comprising 1% to 30% by weight of the acrylic copolymer with respect to 100% by weight of the primer composition.

4. A laminated member comprising: an adherend; a primer layer laminated on the adherend and formed from a primer composition according to any one of claims 1 to 3; and an adhesive layer laminated on the primer layer.

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