Laminate

Abstract

Provided is a laminate in which the top layer has excellent adhesion and excellent water resistance. This laminate has, in this order, a concrete base material, a primer layer, a reinforcing layer, and a top layer containing fluorine atoms, the primer layer containing a component selected from the group consisting of a cured product of an epoxy resin and a urethane resin, and the reinforcing layer containing a resin selected from the group consisting of a urea resin, a urethane resin, and a urethane urea resin. The content of fluorine atoms contained in the top layer is more than 5% by mass but 55% by mass or less.

Description

Technical Field

[0001] The present invention relates to a laminate. Background Art

[0002] In order to suppress the peeling of the concrete substrate, it is known to provide a layer for protecting the surface on the concrete substrate. Patent Document 1 discloses a laminated body in which a primer layer formed of an epoxy resin or the like, a reinforcing layer formed of a urethane resin or the like, and a finishing layer formed of a fluororesin or the like are sequentially arranged on a concrete substrate.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2020-190109 Summary of the invention

[0006] Problem that the invention aims to solve

[0007] In recent years, laminates having a concrete substrate have been required to have further improved performance, specifically, excellent water resistance and excellent adhesion of the outermost layer (hereinafter also referred to as a top layer) of a member disposed on the concrete substrate.

[0008] Here, if the adhesion of the top layer is insufficient, the layers existing thereunder are easily damaged, which may become a factor causing the concrete base material to peel off.

[0009] The present inventors evaluated the laminate described in Patent Document 1 and found that, depending on the composition of the top layer, there is room for improvement in at least one of the water resistance of the laminate and the adhesion of the top layer.

[0010] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a laminate having excellent adhesion of a top layer and excellent water resistance.

[0011] Solutions for solving problems

[0012] The present inventors have conducted intensive studies on the above-mentioned technical problems and have found that, in a laminate having a concrete substrate, a primer layer containing a specified resin, a reinforcing layer containing a specified resin and a top layer containing fluorine atoms in sequence, the desired effect can be obtained if the content of fluorine atoms in the top layer is within a specified range, thereby completing the present invention.

[0013] That is, the inventors have discovered that the above-mentioned technical problems can be solved by the following configuration.

[0014] [1] A laminate comprising, in order, a concrete substrate, a primer layer, a reinforcing layer, and a top layer containing fluorine atoms,

[0015] The primer layer contains at least one component selected from the group consisting of a cured epoxy resin and a urethane resin.

[0016] The reinforcing layer comprises at least one resin selected from the group consisting of urea resin, urethane resin and urethane urea resin.

[0017] The content of the fluorine atoms in the top layer is more than 5 mass % and not more than 55 mass %.

[0018] [2] The laminate according to [1], wherein the content of the fluorine atoms in the top layer exceeds 5% by mass and is 20% by mass or less.

[0019] [3] The laminate according to [1] or [2], wherein the top layer comprises a fluorinated polymer.

[0020] [4] The laminate according to [3], wherein the fluorinated polymer contains units derived from a fluoroolefin.

[0021] [5] The laminate according to [3] or [4], wherein the fluorinated polymer comprises a fluorinated polymer F1 containing a unit based on CF2=CFCl,

[0022] The content of the fluorinated polymer F1 is 50% by mass or more based on the total mass of the fluorinated polymer.

[0023] [6] The laminate according to any one of [3] to [5], wherein the top layer further comprises a non-fluorinated polymer.

[0024] [7] The laminate according to [6], wherein the mass ratio of the content of the fluorine-containing polymer in the top layer to the content of the non-fluorine-containing polymer is 0.11 to 9.0.

[0025] [8] The laminate according to [6] or [7], wherein the non-fluorinated polymer is a (meth)acrylic resin.

[0026] [9] The laminate according to any one of [1] to [8], wherein a ratio of the thickness of the top layer to the thickness of the reinforcing layer is 0.002 to 0.200.

[0027]

[10] The laminate according to any one of [1] to [9], wherein the total light transmittance of the top layer is 30% or less.

[0028] Effects of the Invention

[0029] According to the present invention, it is possible to provide a laminate having excellent adhesion of the top layer and excellent water resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic side view showing an example of the laminated body of the present invention. DETAILED DESCRIPTION

[0031] The meanings of the terms used in the present invention are as follows.

[0032] The numerical range expressed using "to" means a range including the numerical values ​​described before and after "to" as the lower limit and the upper limit.

[0033] Unit refers to the general term for the atomic group based on one molecule of the monomer directly formed by polymerization of the monomer and the atomic group obtained by chemical conversion of a part of the atomic group. The content (mol %) of each unit relative to all units contained in the polymer can be determined by the input amount of the components used in the production of the polymer.

[0034] “(Meth)acrylic acid” is a general term for “acrylic acid” and “methacrylic acid”, and “(meth)acrylate” is a general term for “acrylate” and “methacrylate”.

[0035] The hydrolyzable silyl group refers to a group that can undergo a hydrolysis reaction to form a silanol group.

[0036] The acid value and the hydroxyl value are values ​​measured by the method according to JIS K 0070-3 (1992), respectively.

[0037] The glass transition temperature (Tg) is the midpoint glass transition temperature of a polymer as measured by differential scanning calorimetry (DSC).

[0038] The number average molecular weight (Mn) is a value measured by gel permeation chromatography using polystyrene as a standard substance.

[0039] The content (mass %) of fluorine atoms in the top layer is the content of fluorine atoms in the components constituting the top layer, and can be calculated based on the input amounts of the components used to form the top layer. Alternatively, the value of the above content can also be calculated as the content (mass %) of fluorine atoms calculated based on the surface analysis of the top layer using fluorescent X-ray analysis (XRF).

[0040] The thickness of the laminate is a value measured using an eddy current film thickness meter. As an eddy current film thickness meter, for example, EDY-5000 manufactured by Sanko Electronics Co., Ltd. can be used. The thickness of each layer in the laminate can be calculated by observing the cross section of the laminate using a scanning electron microscope equipped with an energy dispersive X-ray analyzer and the ratio of the thickness of each layer and the thickness of the laminate.

[0041] The total light transmittance is a value measured using illuminant D in accordance with JIS K 7361-1:1997.

[0042] The solid content mass of the coating composition refers to the mass after removing the solvent from the coating composition when the coating composition contains a solvent. It should be noted that the components constituting the solid content of the coating composition other than the solvent are regarded as solid components even if they are in liquid form. It should be noted that the solid content mass of the coating composition is obtained as the mass remaining after heating 1 g of the coating composition at 130° C. for 20 minutes.

[0043] The laminate of the present invention (hereinafter also referred to as the present laminate) comprises, in order, a concrete substrate, a primer layer, a reinforcing layer and a top layer having fluorine atoms, wherein the primer layer comprises at least one component selected from the group consisting of a cured epoxy resin and a urethane resin, the reinforcing layer comprises at least one resin selected from the group consisting of a urea resin, a urethane resin and a urethane urea resin, and the content of fluorine atoms in the top layer exceeds 5% by mass and is not more than 55% by mass.

[0044] The top layer of the present laminate has excellent adhesion and excellent water resistance. The details of the reason are not yet clear, but it is speculated that by making the content of fluorine atoms in the top layer exceed 5% by mass, the water repellency function brought by fluorine atoms can be fully exerted, and the water resistance of the laminate is improved. In addition, it is speculated that by making the content of fluorine atoms in the top layer less than 55% by mass, the affinity between the top layer and the reinforcing layer is improved, thereby improving the adhesion of the reinforcing layer adjacent to the top layer based on fluorine atoms.

[0045] First, the structure of the present laminate is described with reference to the attached Figure 1 While explaining.

[0046] Figure 1 1 is a schematic side view showing the layer structure of a laminate 10 according to one embodiment of the present invention. The laminate 10 includes a concrete base material 12, a primer layer 14, a reinforcing layer 16, and a cap layer 18, and the layers are arranged in this order.

[0047] The laminate 10 may further include other layers unless it violates the spirit of the present invention.

[0048] Hereinafter, each member constituting the present laminate will be described in detail.

[0049] The present laminate has a concrete base material. The concrete base material refers to a base material whose material constituting the base material includes concrete, and may include materials other than concrete (for example, metal, etc.).

[0050] The thickness of the concrete base material is preferably 10 to 300 cm, more preferably 15 to 200 cm.

[0051] The present laminate has a primer layer. The primer layer has, for example, a function of improving the coating properties of a coating composition used for forming an adjacent layer and a function of improving the adhesion between a concrete substrate and other layers.

[0052] The primer layer contains at least one component selected from the group consisting of a cured product of an epoxy resin and a urethane resin (hereinafter, also referred to as a specific resin X).

[0053] The primer layer may contain only one of these components, or may contain two or more of them.

[0054] The epoxy resin is a compound having two or more epoxy groups. The epoxy resin may further have other reactive groups other than the epoxy group.

[0055] Specific examples of the epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, and aliphatic epoxy resin.

[0056] As the epoxy resin, an epoxy resin for forming a clear primer layer described in Japanese Patent Application Laid-Open No. 2020-190109 can be used.

[0057] The cured product of epoxy resin refers to a cured product obtained by a reaction between epoxy resin and a curing agent (eg, an amine compound, an acid anhydride, a catalyst).

[0058] The primer layer may contain two or more types of cured epoxy resins.

[0059] The urethane resin is a resin having a urethane bond, and is obtained by, for example, reacting a mixture containing a polyol (eg, acrylic polyol, polyester polyol, polyether polyol, propylene glycol) and containing at least one of an isocyanate compound and a urethane prepolymer.

[0060] As the urethane resin, a urethane resin for forming a clear primer layer described in Japanese Patent Application Laid-Open No. 2020-190109 can be used.

[0061] The primer layer may contain two or more types of urethane resins.

[0062] The content of the specific resin X is preferably 10 to 100% by mass, more preferably 50 to 100% by mass, based on the total mass of the primer layer.

[0063] The primer layer may contain components other than those described above. Examples of such components include additives.

[0064] As a specific example of the additive that can be contained in the primer layer, tetraethoxysilane can be mentioned.

[0065] When the primer layer contains an additive, the content of the additive is preferably 1 to 20% by mass, more preferably 5 to 10% by mass, relative to the total mass of the primer layer.

[0066] The thickness of the primer layer is preferably 5 to 100 μm, more preferably 10 to 80 μm.

[0067] The present laminate has a reinforcing layer. The reinforcing layer has a function of, for example, suppressing peeling of a concrete base material.

[0068] The reinforcing layer contains at least one resin selected from the group consisting of urea resins, urethane resins, and urethane urea resins (hereinafter also referred to as specific resin Y). The reinforcing layer may contain only one of these resins, or may contain two or more of them.

[0069] The urea resin is a resin having a urea bond, and is obtained by, for example, reacting a mixture containing an amine compound (eg, polyetheramine, aromatic polyamine) and an isocyanate compound.

[0070] The reinforcing layer may contain two or more urea resins.

[0071] The details of the urethane resin are as described in the primer layer. The reinforcing layer may contain two or more urethane resins.

[0072] The urethane urea resin is a resin having a urethane bond and a urea bond, and is obtained by, for example, reacting a mixed solution containing a urethane resin (urethane prepolymer) having an isocyanate group at a terminal and an amine compound.

[0073] As the urethane urea resin, a resin formed using a coating material containing an isocyanurate compound, an isocyanate prepolymer, and an alicyclic diamine compound described in JP-A-2020-190109 can be used.

[0074] The reinforcing layer may contain two or more urethane urea resins.

[0075] The content of the specific resin Y is preferably 10 to 100% by mass, more preferably 50 to 100% by mass, based on the total mass of the reinforcing layer.

[0076] The reinforcing layer may contain components other than those described above. Examples of such components include additives.

[0077] Specific examples of additives that may be contained in the reinforcing layer include silica particles, ultraviolet absorbers, and light stabilizers.

[0078] When the reinforcing layer contains an additive, the content of the additive is preferably 0.01 to 10% by mass, more preferably 0.1 to 8% by mass, based on the total mass of the reinforcing layer.

[0079] The thickness of the reinforcing layer is preferably 5 to 500 μm, more preferably 20 to 400 μm.

[0080] The present laminate has a top layer containing fluorine atoms. The top layer is a layer disposed on the outermost surface of the present laminate and has the function of protecting the concrete substrate. In addition, as described above, the top layer of the present laminate has the function of improving the water resistance of the present laminate.

[0081] The content of fluorine atoms in the top layer is more than 5 mass % and less than 55 mass %, preferably more than 5 mass % and less than 20 mass %, more preferably 10 to 20 mass %.

[0082] When the content of fluorine atoms exceeds 5% by mass, the present laminate has excellent water resistance. When the content of fluorine atoms is 55% by mass or less, the top layer has excellent adhesion.

[0083] From the viewpoint of achieving more excellent weather resistance of the present laminate, the top layer preferably contains a fluorinated polymer. The top layer may contain two or more fluorinated polymers.

[0084] The fluorine-containing polymer may or may not have a cross-linked structure.

[0085] From the viewpoint of water resistance and weather resistance of the present laminate, the fluorinated polymer preferably contains units derived from a fluoroolefin (hereinafter also referred to as units F-1).

[0086] Fluoroolefins are olefins in which one or more hydrogen atoms are substituted with fluorine atoms. One or more hydrogen atoms of the fluoroolefins that are not substituted with fluorine atoms may be substituted with chlorine atoms. The carbon number of the fluoroolefins is preferably 2 to 8, and particularly preferably 2 to 4.

[0087] Specific examples of fluoroolefins include CF2=CF2, CF2=CFCl, CF2=CHF, CH2=CF2, CF2=CFCF3, CF2=CHCF3, CF3CH=CHF, CF3CF=CH2, CH2=CX f1 (CF2) n1 Y f1 (Where X f1 and Y f1 The monomer represented by ) is independently a hydrogen atom or a fluorine atom, and n1 is an integer from 2 to 10. From the viewpoint of excellent weather resistance of the present laminate, preferably CF2=CF2, CH2=CF2, CF2=CFCl, CF3CH=CHF, CF3CF=CH2, more preferably CF2=CF2 or CF2=CFCl, and further preferably CF2=CFCl.

[0088] Two or more fluoroolefins may be used in combination.

[0089] From the viewpoint of weather resistance of the present laminate, the content of the units F-1 is preferably from 20 to 100 mol %, more preferably from 30 to 70 mol %, further preferably from 40 to 60 mol % based on all units contained in the fluorinated polymer.

[0090] The fluorine-containing polymer may contain a unit having at least one of an aliphatic hydrocarbon ring and an aromatic ring (hereinafter also referred to as unit F-2). The unit F-2 is preferably a unit based on a monomer having at least one of an aliphatic hydrocarbon ring and an aromatic ring (hereinafter also referred to as monomer f2).

[0091] The unit F-2 is preferably a unit having no fluorine atom.

[0092] Specific examples of aliphatic hydrocarbon rings include monocyclic aliphatic hydrocarbons such as cyclobutane, cyclopentane, cyclohexane, cycloheptane, and cyclooctane, polycyclic aliphatic hydrocarbons such as 4-cyclohexylcyclohexane and decalin, norbornane, aliphatic hydrocarbons having a bridged ring structure such as 1-adamantyl, and aliphatic hydrocarbons having a spiro ring structure such as spiro[3.4]octyl.

[0093] Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, toluene, xylene, naphthalene, phenol, and benzoic acid, and aromatic heterocyclic rings such as furan, thiophene, pyrrole, and pyridine.

[0094] As the monomer f2, vinyl ether, vinyl ester, allyl ether, allyl ester, and (meth)acrylate having at least one of an aliphatic hydrocarbon ring and an aromatic ring are preferred.

[0095] Specific examples of monomer f2 include cyclohexyl (meth)acrylate, cyclohexyl vinyl ether, cyclohexanedimethanol monovinyl ether (CH2=CHO-CH2-cycloC6H 10 -CH2OH), CH2=CHCH2O-CH2-cycloC6H 10 -CH2OH, CH2=CHO-CH2-cycloC6H 10 -CH2-(OCH2CH2) 15 OH, vinyl benzoate, vinyl tert-butyl benzoate, benzyl (meth)acrylate.

[0096] It should be noted that "-cycloC6H 10 -" represents cyclohexylene, "-cycloC6H 10 -" is usually a 1,4-bonding site.

[0097] Two or more monomers f2 may be used in combination.

[0098] When the fluorinated polymer contains the unit F-2, the content of the unit F-2 is preferably 20 to 50 mol %, more preferably 25 to 45 mol %, further preferably 30 to 40 mol % based on all the units contained in the fluorinated polymer.

[0099] The fluorine-containing polymer may include a unit having neither an aliphatic hydrocarbon ring nor an aromatic ring and having at least one of a hydroxyl group and a carboxyl group (hereinafter also referred to as a unit F-3). The unit F-3 is preferably a unit having no fluorine atom.

[0100] Unit F-3 can be the unit based on the monomer (hereinafter also referred to as monomer f3) with at least one of hydroxyl and carboxyl, or can be the unit obtained by converting the group into at least one of hydroxyl and carboxyl in the fluoropolymer comprising the unit with the group that can be converted into hydroxyl or carboxyl. As such unit, polycarboxylic acid, its acid anhydride etc. can be listed to react with the fluoropolymer comprising the unit with hydroxyl, and a part of hydroxyl or all of them are converted into the unit obtained by carboxyl.

[0101] At least a portion of the hydroxyl or carboxyl groups possessed by monomer f3 may be cross-linked with a curing agent (e.g., a compound having more than two isocyanate groups in one molecule, a compound having more than two epoxy groups in one molecule), or may remain without being cross-linked with the curing agent. When the hydroxyl or carboxyl groups possessed by monomer f3 are cross-linked with the curing agent, the water resistance of this laminate is more excellent.

[0102] Examples of the monomer f3 having a hydroxyl group include vinyl ethers, vinyl esters, allyl ethers, allyl esters, (meth)acrylates, and allyl alcohols having a hydroxyl group. From the viewpoint of weather resistance of the present laminate, the monomer f3 having a hydroxyl group is preferably vinyl ether.

[0103] Specific examples of the monomer f3 having a hydroxyl group include CH2=CHOCH2CH2OH, CH2=CHCH2OCH2CH2OH, CH2=CHOCH2CH2CH2CH2OH, and CH2=CHCH2OCH2CH2CH2CH2OH. From the viewpoint of copolymerizability with fluoroolefins, CH2=CHCH2OCH2CH2OH or CH2=CHOCH2CH2CH2CH2OH is preferred.

[0104] Examples of the monomer f3 having a carboxyl group include unsaturated carboxylic acid, (meth)acrylic acid, and monomers obtained by reacting a carboxylic anhydride with a hydroxy group of the above-mentioned monomer having a hydroxy group.

[0105] Specific examples of the monomer f3 having a carboxyl group include CH2=CHCOOH, CH(CH3)=CHCOOH, CH2=C(CH3)COOH, HOOCCH=CHCOOH, CH2=CH(CH2)n11 COOH (where n11 represents an integer from 1 to 10), CH2=CHO(CH2) n12 OC(O)CH2CH2COOH (wherein n12 represents an integer of 1 to 10). From the viewpoint of copolymerizability with fluoroolefins, CH2═CH(CH2) is preferred. n11 COOH or CH2=CHO(CH2) n12 OC(O)CH2CH2COOH.

[0106] Two or more monomers f3 may be used in combination.

[0107] When the fluorinated polymer contains the unit F-3, the content of the unit F-3 is preferably more than 0 mol% and 30 mol% or less, more preferably 1 to 15 mol%, further preferably 1.5 to 5 mol%.

[0108] The fluorine-containing polymer may include a unit (hereinafter also referred to as unit F-4) based on a monomer (hereinafter also referred to as monomer f4) having neither an aliphatic hydrocarbon ring nor an aromatic ring and having neither a hydroxyl group nor a carboxyl group. Unit F-4 is preferably a unit having no fluorine atom.

[0109] Unit F-4 may have a crosslinkable group other than a hydroxyl group and a carboxyl group. Specific examples of such a group include an amino group, an epoxy group, an oxetanyl group, and a hydrolyzable silyl group.

[0110] Monomer f4 may be one or more selected from the group consisting of olefins, vinyl ethers, vinyl esters, allyl ethers, allyl esters and (meth)acrylates. From the viewpoint of copolymerizability with fluoroolefins and weather resistance of the fluorinated polymer, at least one of vinyl ethers and vinyl esters is preferred, and vinyl ether is particularly preferred.

[0111] Specific examples of monomer f4 include ethylene, propylene, 1-butene, ethyl vinyl ether, tert-butyl vinyl ether, 2-ethylhexyl vinyl ether, vinyl acetate, vinyl pivalate, vinyl neononanoate (manufactured by HEXION, trade name "VeoVa9"), vinyl neodecanoate (manufactured by HEXION, trade name "VeoVa10"), and tert-butyl (meth)acrylate.

[0112] Two or more monomers f4 may be used in combination.

[0113] When the fluorinated polymer contains the unit F-4, the content of the unit F-4 is preferably from 10 to 40 mol%, more preferably from 20 to 30 mol%, based on all the units contained in the fluorinated polymer.

[0114] The Tg of the fluorinated polymer is preferably 30 to 60°C, more preferably 45 to 50°C.

[0115] The Mn of the fluorinated polymer is preferably 1,000 to 1,000,000.

[0116] When the fluorinated polymer has a hydroxyl value, the hydroxyl value of the fluorinated polymer is preferably from 10 to 100 mgKOH / g, more preferably from 40 to 60 mgKOH / g.

[0117] The fluorinated polymers may be used in combination of two or more kinds.

[0118] When the top layer contains a fluoropolymer, the content of the fluoropolymer is preferably 50 to 90% by mass, more preferably 60 to 80% by mass, relative to the total mass of the top layer. If the content of the fluoropolymer is 50% by mass or more, the water resistance of the laminate is further excellent. If the content of the fluoropolymer is 90% by mass or less, the adhesion of the top layer is further excellent.

[0119] Fluoropolymers are manufactured by known methods. For example, fluoropolymers are obtained by copolymerizing monomers in the presence of a solvent and a free radical polymerization initiator. As methods for manufacturing fluoropolymers, solution polymerization and emulsion polymerization can be cited. During or after the manufacture of the fluoropolymer, a polymerization stabilizer, a polymerization inhibitor, a surfactant, etc. can be used as needed.

[0120] As the fluorinated polymer, commercially available products may also be used. Specific examples include the "LUMIFLON" series (manufactured by AGC), the "Fluon" series (manufactured by AGC), the "Kynar" series (manufactured by Arkema), the "Zeffle" series (manufactured by DAIKIN INDUSTRIES, LTD.), the "Eterflon" series (manufactured by Eternal Materials Co., Ltd.), and the "Zendura" series (manufactured by Honeywell).

[0121] One preferred embodiment of the top layer is an embodiment in which the top layer comprises a fluorinated polymer F1 containing a unit based on CF2=CFCl. The fluorinated polymer F1 is one embodiment of the above-mentioned fluorinated polymer.

[0122] When the top layer comprises fluorinated polymer F1, the top layer may comprise a fluorinated polymer other than fluorinated polymer F1 (ie, a fluorinated polymer not comprising units based on CF2=CFCl) or may comprise no fluorinated polymer other than fluorinated polymer F1.

[0123] When the top layer contains the fluorinated polymer F1, the content of the fluorinated polymer F1 is preferably 50% by mass or more, more preferably 70% by mass or more, and further preferably 90% by mass or more relative to the total mass of the fluorinated polymer contained in the top layer. When the content of the fluorinated polymer F1 is 50% by mass or more, the water resistance of the present laminate and the adhesion of the top layer are further excellent.

[0124] When the top layer contains the fluorinated polymer F1, the content of the fluorinated polymer F1 is preferably 100 mass % or less based on the total mass of the fluorinated polymer contained in the top layer.

[0125] From the viewpoint of further improving the adhesion of the top layer, the top layer preferably further contains a non-fluorinated polymer.

[0126] Specific examples of the non-fluorinated polymer include (meth)acrylic resins, alkyd resins, polyester resins, epoxy resins, vinyl acetate resins, vinyl chloride resins, phenolic resins, modified polyester resins, acrylic silicone resins, silicone resins, etc. Among them, (meth)acrylic resins are preferred from the viewpoint of better adhesion of the top layer.

[0127] The (meth)acrylic resin is a polymer including a (meth)acrylate-based unit or a cross-linked product thereof.

[0128] Examples of the (meth)acrylate include alkyl (meth)acrylates, aryl (meth)acrylates, etc. Specific examples of the (meth)acrylate include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, n-hexyl (meth)acrylate, cyclohexyl (meth)acrylate, lauryl (meth)acrylate, 2-ethylhexyl (meth)acrylate, benzyl (meth)acrylate, and phenyl (meth)acrylate.

[0129] (Meth)acrylates may have crosslinking groups such as hydroxyl, carboxyl, amino, epoxy, oxetanyl, and hydrolyzable silyl groups. The crosslinking groups may remain unreacted, or may be crosslinked intramolecularly or by a curing agent having a group that can react with the crosslinking groups.

[0130] Two or more (meth)acrylic resins may be used in combination.

[0131] The Tg of the non-fluorine polymer is preferably -20 to 40° C., more preferably -15 to 30° C. When the Tg of the non-fluorine polymer is within the above range, film-forming properties are good.

[0132] When the top layer contains a non-fluorinated polymer, the content of the non-fluorinated polymer is preferably 5 to 40% by mass, more preferably 10 to 30% by mass, based on the total mass of the top layer.

[0133] When the top layer contains a fluorinated polymer and a non-fluorinated polymer, the mass ratio of the content of the fluorinated polymer to the content of the non-fluorinated polymer (the content of the fluorinated polymer / the content of the non-fluorinated polymer) is preferably 0.11 to 9.0, more preferably 1 to 7, and further preferably 2 to 5. If the mass ratio is 0.11 or more, the water resistance of the present laminate is further excellent. If the mass ratio is 9.0 or less, the adhesion of the top layer is further excellent.

[0134] The top layer may contain components other than those mentioned above. Examples of such components include additives.

[0135] Examples of the additives include curing agents, curing catalysts, ultraviolet absorbers, light stabilizers, matting agents, leveling agents, surface conditioners, deaerators, heat stabilizers, thickeners, dispersants, surfactants, antistatic agents, rust inhibitors, antifouling agents, anti-fouling treatment agents, plasticizers, adhesives, and the like.

[0136] When the top layer contains an additive, the content of the additive is preferably more than 0% by mass and 10% by mass or less relative to the total mass of the top layer.

[0137] The thickness of the top layer is preferably 10 to 80 μm, more preferably 40 to 60 μm.

[0138] The ratio of the thickness of the top layer to the thickness of the reinforcing layer (thickness of the top layer / thickness of the reinforcing layer) is preferably 0.002 to 0.200, more preferably 0.01 to 0.190, and further preferably 0.02 to 0.180. If the above ratio is 0.002 or more, the weather resistance and water resistance of the laminate are further excellent. If the above ratio is 0.200 or less, the adhesion of the top layer is further excellent.

[0139] The total light transmittance of the top layer is preferably 30% or less.

[0140] The top layer is preferably formed of a coating composition containing a fluorine-containing polymer (hereinafter also referred to as the present coating). The fluorine-containing polymer in the present coating is as described above.

[0141] The content of the fluorinated polymer is preferably 50 to 80% by mass, more preferably 60 to 70% by mass, based on the solid content mass of the coating material.

[0142] The present coating material may also contain the above-mentioned non-fluorinated polymer, additives and the like.

[0143] When the present coating material contains a non-fluorinated polymer, the content of the non-fluorinated polymer is preferably 10 to 30% by mass, more preferably 15 to 25% by mass, based on the solid content mass of the present coating material.

[0144] When the present coating material contains an additive, the content of the additive is preferably more than 0% by mass and 30% by mass or less relative to the solid content mass of the present coating material.

[0145] The coating material may be a coating material in which the fluorine-containing polymer is dissolved or dispersed in a liquid medium, or may be a coating material substantially containing no liquid medium (powder coating material, etc.).

[0146] As the liquid medium, organic solvents and water can be listed, and as the coating dissolved or dispersed in the liquid medium, coatings dissolved in organic solvents etc. (solvent-based coatings, etc.) and coatings dispersed in water (water-based coatings, etc.) can be listed. From the viewpoint of reducing environmental load, this coating is preferably a water-based coating.

[0147] The fact that the present coating material contains substantially no liquid medium means that the content of the liquid medium is 0.1% by mass or less relative to the total mass of the present coating material.

[0148] Examples of the organic solvent include ketone solvents, ester solvents, hydrocarbon solvents, alcohol solvents, glycol ether solvents, and glycol ester solvents.

[0149] Specific examples of the ketone solvent include acetone, methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketone, and diacetone alcohol.

[0150] Specific examples of the ester solvent include ethyl acetate and butyl acetate.

[0151] Specific examples of the hydrocarbon solvent include hexane, heptane, cyclohexane, xylene, toluene, Solvesso 100 manufactured by ExxonMobil Corporation, Solvesso 150 manufactured by ExxonMobil Corporation, and aromatic hydrocarbon solvents (mineral spirits, etc.).

[0152] Specific examples of the alcohol solvent include butanol.

[0153] Specific examples of the glycol ether-based solvent include ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, and propylene glycol monopropyl ether.

[0154] Specific examples of the glycol ester-based solvent include 1-methoxypropyl-2-acetate.

[0155] When the present coating material contains a liquid medium, the content of the liquid medium is preferably 10 to 95% by mass, more preferably 20 to 90% by mass, based on the total mass of the present coating material.

[0156] The coating material can be produced by mixing a fluorine-containing polymer with an optional component, for example. The liquid medium can be a polymerization solvent used when producing the fluorine-containing polymer.

[0157] As an example of the method for producing the present laminate, there is mentioned a method of forming a primer layer on a concrete base material, forming a reinforcing layer on the primer layer, and then forming a cap layer on the reinforcing layer.

[0158] Specific examples of the method for forming each layer include a method of applying the coating composition for forming each layer by using a spray, an applicator, a die coater, a bar coater, a roll coater, a comma coater, a roller brush, a brush, or a doctor blade.

[0159] When the coating composition for forming each layer contains a liquid medium, after the coating composition is applied, natural drying or heat drying may be performed in order to remove the solvent in the coating composition.

[0160] Example

[0161] The present invention is described in detail below by way of examples. Examples 1 and 2 are embodiments, and Examples 3 and 4 are comparative examples. However, the present invention is not limited to these examples. It should be noted that the blending amount of each component in the table described below represents a mass basis.

[0162] <Abbreviations and details of ingredients used>

[0163] 〔monomer〕

[0164] CTFE: Chlorotrifluoroethylene

[0165] CHVE: Cyclohexyl vinyl ether

[0166] EVE: Ethyl Vinyl Ether

[0167] CHMVE: Cyclohexanedimethanol monovinyl ether

[0168] CM-EOVE: CH2=CHOCH2-cycloC6H 10 -CH2O(CH2CH2O)nH(n=15)

[0169] 〔Dispersion liquid〕

[0170] Dispersion D F1 : Fluorine-containing polymer F1 (hydroxyl value: 49 mgKOH / g, fluorine atom content: 23 mass%, SP value: 17.8 (J / cm 3 ) 1 / 2, average particle size: 150 nm, Tg: 45°C) are dispersed in water, and the concentration of the fluoropolymer F1 is 50% by mass. The fluoropolymer F1 comprises 50 mol% of units based on CTFE, 15 mol% of units based on CHVE, 25 mol% of units based on EVE, 9 mol% of units based on CHMVE and 1 mol% of units based on CM-EOVE, relative to all units contained in the fluoropolymer.

[0171] Dispersion D F2 : An aqueous dispersion in which particles of a fluoropolymer F2, which is polyvinylidene fluoride, are dispersed in water and the concentration of the fluoropolymer F2 is 50% by mass

[0172] Dispersion D A1 : YODOSOL AD-179 (manufactured by Henkel), an aqueous dispersion in which particles of a (meth)acrylic resin are dispersed in water and the concentration of the (meth)acrylic resin A1 (Tg: -10°C) is 44% by mass

[0173] [Example 1]

[0174] [Preparation of coating composition for forming reinforcing layer]

[0175] 49 parts by mass of an isocyanurate compound (Desmodur Z4470 BA (manufactured by Sumika Covestro Urethane Co., Ltd.), a trimer of isophorone diisocyanate), 100 parts by mass of the following isocyanate prepolymer P1, 53 parts by mass of an alicyclic diamine compound (Desmophen NH1420, manufactured by Sumika Covestro Urethane Co., Ltd.), 16 parts by mass of mineral spirits, 13 parts by mass of hydrophobic silica, 1.7 parts by mass of an ultraviolet absorber, and 1.7 parts by mass of a light stabilizer were uniformly mixed to prepare a coating composition for forming a reinforcing layer.

[0176] Isocyanate prepolymer P1: 100 parts by mass of PTG L2000 (manufactured by Hodogaya Chemical Industry Co., Ltd., a modified polytetramethylene glycol having a molecular weight of 2000) and 21 parts by mass of isophorone diisocyanate were mixed and reacted at 80° C. for 2 hours in the presence of 0.003 parts by mass of NEOSTANN U-830 (manufactured by Nitto Kasei Co., Ltd., dioctyltin, catalyst) to obtain a prepolymer.

[0177] [Preparation of coating composition for forming top layer]

[0178] The dispersion D F1 (70 parts by mass), dispersion D A1(20 parts by mass) and a film-forming aid (ethylene glycol mono-2-ethylhexyl ether (EHG), boiling point: 229° C.) (10 parts by mass) were mixed to obtain a coating composition 1 as an aqueous coating.

[0179] [Manufacturing of laminated body]

[0180] On the surface of the concrete substrate, the 2 An epoxy resin (Bondo VM Primer (manufactured by KONISHI Co., Ltd.), one-component epoxy resin) was applied in a manner and allowed to stand at room temperature (23° C.) for 12 hours to form a primer layer containing a cured product of the epoxy resin.

[0181] Next, the surface of the primer layer was heated to 1.0 kg / m 2 The reinforcing layer forming composition was applied in a manner of , and the mixture was left to stand at room temperature (23° C.) for 12 hours to form a reinforcing layer (thickness: 300 μm).

[0182] Next, coating composition 1 was applied to the surface of the reinforcing layer and left at room temperature (23° C.) for 14 hours to form a top layer. In this manner, laminate 1 of Example 1 was obtained.

[0183] [Example 2~Example 4]

[0184] Coating compositions 2 to 4 for forming a top layer were obtained in the same manner as in Example 1 except that the composition of the coating composition for forming the top layer was changed as shown in Table 1. Laminated bodies 2 to 4 of Examples 2 to 4 were obtained in the same manner as in Example 1 except that the obtained coating compositions were used.

[0185] [Content of fluorine atoms in the top layer]

[0186] The content of fluorine atoms in the top layer is calculated from the amounts of the components charged to form the top layer.

[0187] [Adhesion]

[0188] The adhesion of the top layer was determined by the cross-cut method (JIS K 5600-5-6).

[0189] Specifically, the surface of the top layer side of each laminate was cut into a checkerboard shape of 100 grids with an interval of 1 mm, and an adhesive tape was attached thereto. Then, the adhesion of the top layer was evaluated according to the number of grids (grid number / 100) of the 100 grids where the top layer was not peeled off by the adhesive tape when the adhesive tape was peeled off, according to the following criteria. The results are shown in Table 1. If the evaluation is B or above, it can be said that the adhesion of the top layer is excellent.

[0190] A: The number of grids exceeds 95.

[0191] B: The number of grids is 70 or more and 95 or less.

[0192] C: The number of cells is less than 70.

[0193] [Water resistance]

[0194] The laminate was immersed in warm water at 60°C for 18 hours, then immersed in cold water at 5°C for 15 hours, and then dried at 5°C. The water resistance of the laminate after drying was evaluated based on the appearance of the laminate according to the following criteria. The results are shown in Table 1. If the evaluation is B or higher, the laminate can be said to have excellent water resistance.

[0195] A: Whitening and blistering were not observed in 80% or more of the top layer surface area.

[0196] B: Whitening and blistering were not observed in an area of ​​50% or more and less than 80% of the top layer surface.

[0197] C: Whitening and blistering were observed in more than 50% of the surface area of ​​the top layer.

[0198] [Table 1]

[0199]

[0200] As shown in Table 1, it was confirmed that the top layer of the laminate of the present invention was excellent in adhesion and excellent in water resistance (Examples 1 and 2).

[0201] It should be noted that the entire contents of the specification, claims, drawings, and abstract of Japanese Patent Application No. 2022-161560 filed on October 6, 2022 are cited herein and introduced as a disclosure of the specification of the present invention.

[0202] Description of Reference Numerals

[0203] 10 Laminated body

[0204] 12 Concrete substrate

[0205] 14 Primer layer

[0206] 16 Enhancement Layer

[0207] 18 Top floor

Claims

1. A laminate, characterized in that: The invention has a concrete substrate, a primer layer, a reinforcing layer and a top layer containing fluorine atoms in sequence, The primer layer comprises at least one component selected from the group consisting of a cured epoxy resin and a urethane resin. The reinforcing layer comprises at least one resin selected from the group consisting of urea resin, urethane resin and urethane urea resin, The content of the fluorine atoms in the top layer exceeds 5 mass % and is 55 mass % or less.

2. The laminate according to claim 1, wherein The content of the fluorine atoms in the top layer exceeds 5 mass % and is 20 mass % or less.

3. The laminate according to claim 1 or 2, wherein: The top layer comprises a fluoropolymer.

4. The laminate according to claim 3, wherein: The fluoropolymer comprises fluoroolefin-based units.

5. The laminate according to claim 3, wherein The fluoropolymer comprises a fluoropolymer F1 comprising units based on CF2=CFCl, The content of the fluorinated polymer F1 is 50% by mass or more based on the total mass of the fluorinated polymer.

6. The laminate according to claim 3, wherein The top layer also comprises a non-fluoropolymer.

7. The laminate according to claim 6, wherein: The mass ratio of the content of the fluorine-containing polymer in the top layer to the content of the non-fluorine-containing polymer is 0.11 to 9.

0.

8. The laminate according to claim 6, wherein: The non-fluorine polymer is a (meth)acrylic resin.

9. The laminate according to claim 1 or 2, wherein: The ratio of the thickness of the top layer to the thickness of the reinforcement layer is 0.002 to 0.

200.

10. The laminate according to claim 1 or 2, wherein: The total light transmittance of the top layer is less than 30%.

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