A primer composition for forming a primer layer for a silicone-based topcoat layer, a primer layer for a silicone-based topcoat layer, a laminated structure, and a method for manufacturing a laminated structure.

Abstract

This invention provides an undercoat layer for a silicone-based topcoat layer that has good water-repellent durability even when the substrate is a metal part. [Solution] A primer composition for forming a primer layer for a silicone-based topcoat layer, comprising a sulfur-based functional group-containing silicone, a first curing catalyst, and a volatile organic solvent, wherein the blending ratio of the sulfur-based functional group-containing silicone is 70 parts by mass or more and less than 100 parts by mass per 100 parts by mass of the solid content of the primer composition, and the heat residue after heat treatment at 105°C for 60 minutes is 0.25% by mass or more and 20% by mass or less.

Description

[Technical Field]

[0001] The present invention relates to an undercoat composition for forming an undercoat layer for a silicone-based topcoat layer, an undercoat layer for a silicone-based topcoat layer, a laminated structure, and a method for manufacturing the laminated structure. [Background technology]

[0002] Traditionally, it has been common practice to apply surface protectants to the painted surfaces of automobiles to give them gloss and shine, and to protect the surface.

[0003] As such a surface protective agent, for example, a vehicle coating agent has been proposed that contains a moisture-curable silicone oligomer, a curing catalyst, and a double-ended reactive silicone oil having at least reactive functional groups at both ends of the molecule, wherein the blending ratio of the double-ended reactive silicone oil is 25 parts by weight or more per 100 parts by weight of the moisture-curable silicone oligomer (Patent Document 1).

[0004] Such vehicle coatings maintain good gloss, shine, water repellency, and stain resistance on the metal, painted, or resin surfaces of a vehicle, and can also maintain good gloss, shine, water repellency, and stain resistance even after washing.

[0005] Furthermore, a coating agent has been proposed that offers excellent quick-drying properties and maintains good gloss and shine, water repellency, stain resistance, solvent resistance, acid resistance, and alkali resistance on metal surfaces, painted surfaces, or resin surfaces of various industrial products over a long period of time, and that maintains good gloss and shine, water repellency, and stain resistance even after washing (Patent Document 2). [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2008-75021 [Patent Document 2] Japanese Patent Publication No. 2014-139301 [Overview of the project] [Problems that the invention aims to solve]

[0007] Thus, conventional coating agents are applied to automotive painted surfaces and metal surfaces such as metal parts with the aim of providing water repellency. However, when applied to metal surfaces such as metal parts, the weather resistance and water-repellency durability of the coatings have been insufficient. [Means for solving the problem]

[0008] The gist of this invention is as follows: (1) A primer composition for forming a primer layer for a silicone-based topcoat layer, Sulfur-based functional group-containing silicone, First curing catalyst, and Volatile organic solvents It contains, The proportion of the sulfur-based functional group-containing silicone is 70 parts by mass or more and less than 100 parts by mass per 100 parts by mass of the solid content of the undercoat composition. A primer composition having a heat residue of 0.25% by mass or more and 20% by mass or less after heat treatment at 105°C for 60 minutes. (2) The primer composition according to (1) above, wherein the content of the first curing catalyst is 0.0025 to 5 parts by mass per 100 parts by mass of the primer composition. (3) The primer composition according to (1) or (2) above, wherein the content of the volatile organic solvent is more than 80 parts by mass and less than 100 parts by mass per 100 parts by mass of the primer composition. (4) The silicone-based topcoat layer is a primer composition according to any one of (1) to (3) above, comprising a T-body. (5) The topcoat composition for forming the silicone-based topcoat layer is Silicone resin containing T-body, and Second curing catalyst It contains, The blending ratio of the silicone resin is 60 parts by mass or more and less than 100 parts by mass with respect to 100 parts by mass of the solid content of the topcoat composition. The heat residue after heat treatment at 105 °C for 60 minutes of the topcoat composition is 40% by mass or more. The kinematic viscosity of the topcoat composition is 2 CS or more. The undercoat composition according to any one of (l) to (4) above. (6) The undercoat composition according to (5) above, wherein the content of silicone oil in the topcoat composition is 5% by mass or less. (7) An undercoat layer for a silicone-based topcoat layer formed of the undercoat composition according to any one of (l) to (6) above. (8) A substrate, and An undercoat layer for a silicone-based topcoat layer formed of the undercoat composition according to any one of (l) to (7) above on the substrate. A laminated structure including the same. (9) The laminated structure according to (8) above, further including a silicone-based topcoat layer on the undercoat layer. (10) A method for manufacturing a laminated structure, including applying an undercoat composition for forming an undercoat layer for a silicone-based topcoat layer on a substrate to form an undercoat layer for a silicone-based topcoat layer, wherein the undercoat composition contains a sulfur-based functional group-containing silicone, a first curing catalyst, and a volatile organic solvent and the blending ratio of the sulfur-based functional group-containing silicone is 70 parts by mass or more and less than 100 parts by mass with respect to 100 parts by mass of the solid content of the undercoat composition, the heat residue after heat treatment at 105 °C for 60 minutes is 0.25% by mass or more and 20% by mass or less. A method for manufacturing a laminated structure. (11) The method for manufacturing a laminated structure according to (10) above, further including applying a topcoat composition containing a silicone resin containing a T body and a second curing catalyst on the undercoat layer to form the silicone-based topcoat layer. (12) The blending ratio of the silicone resin is 60 parts by mass or more and less than 100 parts by mass with respect to 100 parts by mass of the solid content of the topcoat composition. The heating residue after heat treatment at 105°C for 60 minutes of the topcoat composition is 40% by mass or more. The kinematic viscosity of the topcoat composition is 2 CS or more. The method for producing a laminated structure according to the above (11). (13) The method for producing a laminated structure according to the above (11) or (12), wherein the content of silicone oil in the topcoat composition is 5% by mass or less. (14) The method for producing a laminated structure according to any one of the above (11) to (13), wherein wiping is performed after applying the topcoat composition.

Advantages of the Invention

[0009] According to the present invention, it is possible to provide an undercoat layer for a silicone-based topcoat layer that has good workability and good weather resistance and water repellency durability even when the base material is a metal surface such as a metal part.

Brief Description of the Drawings

[0011] This disclosure relates to an undercoat composition for forming an undercoat layer for a silicone-based topcoat layer, comprising a sulfur-based functional group-containing silicone, a first curing catalyst, and a volatile organic solvent, wherein the proportion of the sulfur-based functional group-containing silicone is 70 parts by mass or more and less than 100 parts by mass per 100 parts by mass of the solid content of the undercoat composition, and the heat residue after heat treatment at 105°C for 60 minutes is 0.25% by mass or more and 20% by mass or less, and is also referred to as the undercoat composition (also referred to as the undercoat composition).

[0012] This primer composition can form a primer layer for silicone-based topcoats and has excellent workability on substrates. A coating containing the primer layer formed with this primer composition and a silicone-based topcoat not only has high initial water repellency but also exhibits excellent weather resistance and water-repellent durability.

[0013] The silicone contained in this primer composition contains sulfur-based functional groups. Because this primer composition contains sulfur-based functional group-containing silicone, its adhesion strength to the substrate is improved, and when a silicone-based topcoat layer is formed, it exhibits excellent weather resistance and water-repellent durability. Weather resistance can be evaluated based on water repellency after exposure testing. Water-repellent durability can be evaluated based on water repellency after friction and abrasion testing.

[0014] Sulfur-based functional group-containing silicones may contain alkoxysilyl groups. The alkoxysilyl group may also be a trialkoxysilyl group. The trialkoxysilyl group may also be a trimethoxysilyl group.

[0015] A silicone containing an alkoxysilyl group and a sulfur-based functional group is a silicone compound having a sulfur-based functional group and an alkoxysilyl group within its molecule.

[0016] Sulfur-based functional group-containing silicones are silicone compounds that have sulfur-based functional groups in their molecules. Examples of sulfur-based functional groups include mercapto groups, sulfide groups (sulfide bonds), disulfide groups (disulfide bonds), trisulfide groups (trisulfide bonds), tetrasulfide groups (tetrasulfide bonds), thioester groups (thioester bonds), thiourethane groups (thiourethane bonds), and thiourea groups (thiourea bonds). Sulfur-based functional group-containing silicones may contain one or more of these sulfur-based functional groups. Furthermore, sulfur-based functional group-containing silicones may contain one or more of these sulfur-based functional groups.

[0017] Examples of sulfur-containing silicones that include sulfide groups (sulfide bonds) include alkoxysilylthio functional silicones. Alkoxysilylthio functional silicones are, for example, organosilicon compounds that have an alkoxysilyl group and a sulfide bond between sulfur and silicon.

[0018] The alkoxysilyl group may also be a trialkoxysilyl group. The trialkoxysilyl group may also be a trimethoxysilyl group or a triethoxysilyl group. The alkoxysilylthio-functionalized silicone is preferably of the following formula (1): [ka] (In formula (1), R 1 R is an alkyl group having 1 to 6 carbon atoms, preferably 1 to 3 carbon atoms. 2 R is a methyl group or a propyl group, 3 is Si(OR 4 )3 or H, R 4 (where x is an ethyl group or a methyl group, x is 2-3, and y is an integer from 1-6, preferably from 1-3.) Examples include alkoxysilane compounds represented by or their partially hydrolyzed condensates.

[0019] A partially hydrolyzed condensate of an alkoxysilane compound is obtained by adding water to the above-mentioned alkoxysilane compound and raising the temperature while stirring in the presence of a catalyst, thereby causing partial hydrolysis and condensation.

[0020] Sulfur-based functional group-containing silicones may also have a protecting group for the sulfur-based functional group. In formula (1), R 3 is Si(OR 4 )If it is 3, it can function as a protecting group for S. Odor can be suppressed by the presence of a protecting group for sulfur-based functional groups in a sulfur-based functional group-containing silicone.

[0021] The protecting group can be a silyl group, for example, a triethoxysilyl group. A sulfur-based functional group-containing silicone with a protecting group can be, for example, X-12-1056ES manufactured by Shin-Etsu Chemical Co., Ltd. A sulfur-based functional group-containing silicone without a protecting group can be, for example, KBM-803 manufactured by Shin-Etsu Chemical Co., Ltd. or Z-6062 manufactured by Dow Chemical Company.

[0022] Examples of alkoxysilylthio-functional silicones include 3-trimethoxysilylthiopropyltrimethoxysilane, 3-trimethoxysilylthiopropyltriethoxysilane, 3-triethoxysilylthiopropyltrimethoxysilane, 3-triethoxysilylthiopropyltriethoxysilane, and 3-octanoylthio-1-propyltriethoxysilane.

[0023] Examples of disulfide groups (disulfide bonds) include bis(triethoxysilylpropyl) disulfide.

[0024] Examples of trisulfide groups (trisulfide bonds) include bis(triethoxysilylpropyl)trisulfide.

[0025] Examples of tetrasulfide groups (tetrasulfide bonds) include bis(triethoxysilylpropyl)tetrasulfide.

[0026] The sulfur-based functional group-containing silicone may be a mercapto group-containing silicone. The mercapto group-containing silicone is preferably represented by the following formula (2):

Chemical formula

[0027] Examples of R1 include a 3-mercaptopropyl group and the like. In formula (2), if at least one of R 1 is an organic functional group containing a mercapto group, the remaining R 1 may be an alkyl group having 1 to 6 carbon atoms. Examples of the alkyl group having 1 to 6 carbon atoms include a methyl group, an ethyl group, a propyl group, an iso-propyl group, a butyl group, an iso-butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, an iso-pentyl group, a sec-pentyl group, a hexyl group and the like. The alkyl group is preferably a methyl group or an ethyl group, more preferably a methyl group.

[0028] Mercapto group-containing silicones include, for example, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylethoxydimethoxysilane, 3-mercaptopropyldiethoxymethoxysilane, 3-mercaptopropyltriethoxysilane, bis-3-mercaptopropyldimethoxysilane, bis-3-mercaptopropylethoxymethoxysilane, bis-3-mercaptopropyldiethoxysilane, 3-mercaptopropyldimethoxysilane Examples include toxymethylsilane, 3-mercaptopropylethoxymethoxymethylsilane, 3-mercaptopropyldiethoxymethylsilane, tris-3-mercaptopropylmethoxysilane, tris-3-mercaptopropylethoxysilane, bis-3-mercaptopropylmethoxymethylsilane, bis-3-mercaptopropylethoxymethylsilane, 3-mercaptopropylmethoxydimethylsilane, 3-mercaptopropylethoxydimethicilane, or mixtures thereof.

[0029] In sulfur-based functional group-containing silicones, the silicone units can be monomers or oligomers.

[0030] The sulfur-based functional group-containing silicone may be synthesized or commercially available. For example, commercially available alkoxysilylthio functional silicones include CABRUS2, CABRUS4 (polysulfide silane, manufactured by Daiso), 3-triethoxysilylthiopropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., X-12-1056ES, mercapto equivalent 2.79 mmol / g), and SI69 (bis(triethoxysilylpropyl)tetrasulfide, manufactured by Evonik). Mercapto equivalent refers to the number of moles of mercapto groups per gram.

[0031] Examples of commercially available mercapto group-containing silicones include 3-mercaptopropylmethyldimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-802), 3-mercaptopropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-803, mercapto equivalent 5.10 mmol / g), 3-mercaptopropyltrimethoxysilane (manufactured by Dow Chemical Company, Z-6062), and methoxy group-containing polyfunctional mercaptosilane (manufactured by Shin-Etsu Chemical Co., Ltd., Examples include X-12-1154), mercaptomethyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., X-12-1307), methoxy-ethoxy group-containing oligomer having a mercapto group (manufactured by Shin-Etsu Chemical Co., Ltd., X-41-1805), methoxy group-containing oligomer (manufactured by Shin-Etsu Chemical Co., Ltd., X-41-1810, molecular weight 700, mercapto equivalent 2.22 mmol / g), and ethoxy group-containing oligomer (manufactured by Shin-Etsu Chemical Co., Ltd., X-41-1818). These are moisture-curing silicones and may be used individually or in combination of two or more.

[0032] This primer composition contains a silicone containing sulfur-based functional groups in an amount of 70 parts by mass or more and less than 100 parts by mass per 100 parts by mass of solids contained in the primer composition. Because the primer composition contains a sulfur-based functional group-containing silicone in this amount, it can exhibit excellent weather resistance and water-repellent durability when forming a silicone-based topcoat layer.

[0033] The primer composition preferably contains a silicone containing sulfur-based functional groups in an amount of 75 to 99.995 parts by mass, more preferably 80 to 99.99 parts by mass, even more preferably 90 to 99.98 parts by mass, even more preferably 95 to 99.9 parts by mass, even more preferably 96 to 99.8 parts by mass, and even more preferably 97 to 99 parts by mass, per 100 parts by mass of solids contained in the primer composition. By including the above preferred amount of silicone containing sulfur-based functional groups in the primer composition, the primer composition can exhibit even better weather resistance and water-repellent durability when a silicone-based topcoat layer is formed.

[0034] This primer composition has a heat residue of 0.25% by mass or more and 20% by mass or less after heat treatment at 105°C for 60 minutes. This amount of heat residue allows the primer composition to be low-cost and to exhibit excellent weather resistance and water-repellent durability when a silicone-based topcoat layer is formed. If the heat residue exceeds 20% by mass, it is not economical from a cost standpoint, and good weather resistance and water-repellent durability cannot be obtained when a silicone-based topcoat layer is formed. If the heat residue is less than 0.25% by mass, good weather resistance and water-repellent durability cannot be obtained when a silicone-based topcoat layer is formed. The heat residue is the ratio of the mass after heating to the mass before heat treatment, and can be measured under the conditions described in JIS K5601 (2008).

[0035] The primer composition has a heat residue of preferably 10% by mass or less, more preferably 5% by mass or less, even more preferably 4% by mass or less, and even more preferably 3% by mass or less after heat treatment at 105°C for 60 minutes. Having the above-mentioned preferred amount of heat residue in the primer composition allows for a lower cost and provides superior weather resistance and water-repellent durability when a silicone-based topcoat layer is formed.

[0036] The lower limit of the heat residue of this primer composition after heat treatment at 105°C for 60 minutes is preferably 0.3% by mass or more, 0.4% by mass or more, 0.5% by mass or more, 0.6% by mass or more, 0.7% by mass or more, 0.8% by mass or more, 0.9% by mass or more, or 1% by mass or more. By having the lower limit of the heat residue within the above preferred range, this primer composition can exhibit better weather resistance and water-repellent durability when a silicone-based topcoat layer is formed.

[0037] The content of sulfur-based functional group-containing silicone in this primer composition is preferably 0.1 to 12% by mass, more preferably 0.3 to 10% by mass, even more preferably 0.5 to 7% by mass, and even more preferably 1 to 5% by mass. By including sulfur-based functional group-containing silicone in the above preferred amounts, when a silicone-based topcoat layer is formed on the primer layer formed with this primer composition, it is possible to obtain better weather resistance and water-repellent durability.

[0038] The sulfur-based functional group content in the sulfur-based functional group-containing silicone is preferably 1 to 10 mmol / g, 1.5 to 8 mmol / g, or 2 to 6 mmol / g in terms of sulfur-based functional group equivalents. By having the sulfur-based functional group equivalent within the above preferred range, this primer composition can exhibit better weather resistance and water-repellent durability when a silicone-based topcoat layer is formed. The sulfur-based functional group equivalent is the number of moles of sulfur-based functional groups per gram of sulfur-based functional group-containing silicone.

[0039] This primer composition contains a first curing catalyst. The inclusion of the first curing catalyst in this primer composition allows for excellent weather resistance and water-repellent durability when a silicone-based topcoat layer is formed on the primer layer formed with this primer composition.

[0040] The first curing catalyst contained in this primer composition contributes as a curing catalyst for the primer composition after it has been applied to the substrate, and can accelerate the room-temperature humidity curing of the primer composition. The first curing catalyst accelerates the room-temperature humidity curing of the alkoxysilyl groups contained in the primer composition, thereby obtaining excellent adhesion to the substrate.

[0041] The content ratio of the first curing catalyst in this primer composition is preferably 0.0025 to 5 parts by mass, more preferably 0.005 to 2.5 parts by mass, even more preferably 0.01 to 2 parts by mass, and even more preferably 0.05 to 1.5 parts by mass per 100 parts by mass of this primer composition. By having the content ratio of the first curing catalyst within the above preferred range, better adhesion to the substrate can be obtained.

[0042] The first curing catalyst is not particularly limited as long as it is a catalyst capable of curing the primer composition, but may include organometallic catalysts, inorganic acids, organic acids, inorganic bases, organic bases, etc.

[0043] Organometallic catalysts can be, for example, organotin compounds, organoaluminum compounds, organozirconium compounds, or organotitanium compounds.

[0044] Examples of organotin compounds include organotin compounds such as dibutyltin diacetate, dibutyltin dioctylate, dibutyltin dilaurate, tin octoate, dibutyltin di(2-ethylhexanoate), dibutyltin dilaurate, dioctyltin diacetate, dioctyltin di(2-ethylhexanoate), dibutyltin oxide, dibutyltin sulfite, dioctyltin oxide, and dibutyltin fatty acid salts; tin alkoxides such as tin tetra-n-butoxide and tin tetra-tert-butoxide; and tin chelate compounds such as bis(2,4-pentanedionato)tin.

[0045] Examples of organoaluminum compounds include organoaluminum compounds such as aluminum tris(acetylacetone), aluminum tris(acetacetate ethyl), and aluminum diisopropoxy(acetacetate ethyl); aluminum alkoxides such as aluminum triethoxide, aluminum triisopropoxide, aluminum tri-n-propoxide, aluminum trisec-butoxide, and aluminum tri-n-butoxide; aluminum chelate compounds such as tris(2,4-pentanedionato)aluminum, tris(ethylacetacetate)aluminum, bis(ethylacetacetate)(2,4-pentanedionato)aluminum, and bis(ethylacetacetate)(monoacetylacetacetate)aluminum; and alkoxy group-containing aluminum chelate compounds such as aluminum ethylacetacetate diisopropylate.

[0046] Examples of organozirconium compounds include organozirconium compounds such as zirconium(acetylacetone), zirconiumtris(acetylacetone), zirconiumtetrakis(ethylene glycol monomethyl ether), zirconiumtetrakis(ethylene glycol monoethyl ether), and zirconiumtetrakis(ethylene glycol monobutyl ether); zirconium alkoxides such as zirconiumtetra-n-butoxide and zirconiumtetra-n-propoxide; and zirconium chelate compounds such as tetrakis(2,4-pentanedionato)zirconium and tetrakis(ethylacetate)zirconium.

[0047] Examples of organic titanium compounds include organic titanium compounds such as titanium tetrakis(ethylene glycol monomethyl ether), titanium tetrakis(ethylene glycol monoethyl ether), titanium tetrakis(ethylene glycol monobutyl ether), and tetra(2-ethylhexyl) titanate; titanium alkoxides such as titanium tetramethoxide, titanium tetraethoxide, titanium tetraisopropoxide, titanium tetra n-propoxide, titanium tetraisobutoxide, titanium tetra n-butoxide, titanium tetrapentoxide, titanium tetrahexoxide, titanium tetra(2-ethylhexoxide), and titanium tetraoctoxide; titanium chelate compounds such as tetrakis(2,4-pentanedionato)titanium and tetrakis(ethylacetoacetate)titanium; and alkoxy group-containing titanium chelate compounds such as bis(2,4-pentanedionato)bis(2-propanolate).

[0048] Other organometallic catalysts include, in addition to those mentioned above, organometallic compounds such as lead 2-ethylhexanoate, zinc octoate, zinc naphthenate, zinc fatty acids, bismuth octanoate, bismuth 2-ethylhexanoate, bismuth oleate, bismuth neodecanoate, bismuth versatate, bismuth naphthenate, cobalt naphthenate, calcium octoate, and copper naphthenate.

[0049] Examples of inorganic acids include mineral acids such as hydrochloric acid, nitric acid, sulfuric acid, and phosphoric acid.

[0050] Examples of organic acids include formic acid, acetic acid, oxalic acid, and trifluoroacetic acid.

[0051] Examples of inorganic bases include ammonia, sodium hydroxide, and potassium hydroxide.

[0052] Examples of organic bases include alkalis such as ethylenediamine and alkanolamine, alkalis such as organic bases, amino-modified silicones, aminosilanes, silazanes, and amino compounds such as amines.

[0053] The first curing catalyst may be a single catalyst or a combination of two or more catalysts. The first curing catalyst may be a commercially available product.

[0054] This primer composition contains a volatile organic solvent. The inclusion of a volatile organic solvent in this primer composition ensures its stability and ease of application.

[0055] The volatile organic solvent is preferably included in the primer composition in an amount of more than 80 parts by mass and less than 100 parts by mass, more preferably 85 parts by mass and 99.5 parts by mass or less, even more preferably 90 parts by mass and 99 parts by mass or less, even more preferably 92 parts by mass and 98.5 parts by mass or less, and even more preferably 94 parts by mass and 98 parts by mass or less. This makes it easy to control the heat residue of the primer composition after heat treatment at 105°C for 60 minutes to 20% by mass or less.

[0056] The volatile organic solvent can be any solvent that does not substantially react with the sulfur-based functional group-containing silicone, and can be aromatic hydrocarbon organic solvents, aliphatic hydrocarbon organic solvents, ketone organic solvents, ester organic solvents, alcohol organic solvents, etc.

[0057] The volatile organic solvent is preferably an aromatic hydrocarbon organic solvent, an aliphatic hydrocarbon organic solvent, an alcohol organic solvent, or a combination thereof. Aromatic hydrocarbon organic solvents and aliphatic hydrocarbon organic solvents have relatively fast evaporation rates, allowing the primer composition to cure quickly after application to the substrate, thus accelerating the application of the silicone topcoat composition. Alcohol organic solvents can contribute to the stability of the primer composition.

[0058] Aliphatic linear hydrocarbon organic solvents include, for example, linear alkanes such as hexane, n-butane, n-hexane, n-heptane, n-pentane, n-octane, n-nonane, n-decane, n-undecane, n-dodecane, n-tridecane, n-tetradecane, n-pentadecane, n-hexadecane, and n-heptadecane; 2-methylbutane, 2,2-dimethylpropane, 2-methylpentane, 3-methylpentane, 2,2-dimethylbutane, 2,3-dimethylbutane, 2-methylhexane, 3-methylhexane, 2,3-dimethylpentane, 2,4-dimethylpentane, 2,2,3-trimethylpentane, 2,2,4-trimethylpentane, 3,4-diethylhexane, 2,6-dimethyloctane, 3,3-dimethyloctane, 3,5-dimethyloctane, 4,4-dimethyloctane, 3-ethyl-3-methylheptane Examples include branched alkanes such as 2-methylnonane, 3-methylnonane, 4-methylnonane, 5-methylnonane, 2-methylundecane, 3-methylundecane, and 2,2,4,6,6-pentamethylheptane; and cycloalkanes such as cyclopentane, t-decalin, cyclohexane, methylcyclohexane, ethylcyclohexane, 1,2-dimethylcyclohexane, 1,3-dimethylcyclohexane, 1,4-dimethylcyclohexane, propylcyclohexane, isopropylcyclohexane, 1,2-methylethylcyclohexane, 1,3-methylethylcyclohexane, 1,4-methylethylcyclohexane, 1,2,3-trimethylcyclohexane, 1,2,4-trimethylcyclohexane, and 1,3,5-trimethylcyclohexane, which can be used individually or in combination of two or more.

[0059] Examples of aromatic hydrocarbon organic solvents include toluene and xylene, which can be used individually or in combination of two or more.

[0060] Examples of alcohol-based organic solvents include methanol, ethanol, isopropanol, n-butyl alcohol, 2-hydroxy-4-methylpentane, 2-ethylhexyl alcohol, cyclohexanol, ethylene glycol, diethylene glycol, 1,3-butylene glycol, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, and the like. The alcohol-based organic solvent may contain one or more alcohol-based organic solvents. The alcohol-based organic solvent is preferably linear or branched. Furthermore, the alcohol-based organic solvent preferably has 1 to 8 carbon atoms.

[0061] Examples of ketone-based organic solvents include acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, ethyl isoamyl ketone, diisobutyl ketone, methylhexyl ketone, and isophorone, which can be used individually or in combination of two or more.

[0062] Examples of ester-based organic solvents include ethyl acetate, butyl acetate, isobutyl acetate, 2-ethylhexyl acetate, cyclohexyl acetate, 3-methoxybutyl acetate, propylene glycol monomethyl ether acetate, dipropylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, and diethylene glycol monoethyl ether acetate, which can be used individually or in combination of two or more. Ester-based organic solvents are preferably linear or branched. Furthermore, ester-based organic solvents are preferably carbon-numbered (4 to 8).

[0063] The volatile organic solvent may be a mixture of alcohol-based organic solvents, aliphatic linear hydrocarbon-based organic solvents, and aromatic hydrocarbon-based organic solvents in any proportion. For example, the volatile organic solvent may contain alcohol-based organic solvents and aliphatic linear hydrocarbon-based organic solvents in mass ratios of 20:80 to 80:20, 30:70 to 70:30, or 40:60 to 60:40.

[0064] The primer composition may contain a base resin and a crosslinking agent. Examples of base resins include acrylic resins, polyester resins, alkyd resins, and urethane resins. Examples of crosslinking agents include melamine resins, urea resins, polyisocyanate compounds, and blocked polyisocyanate compounds.

[0065] The thickness of the undercoat layer formed with the undercoat composition (cured thickness) may be 0.001 to 70 μm, 0.01 to 50 μm, or 0.05 to 30 μm.

[0066] The silicone-based topcoat layer may contain the T-form (T-unit). Silicone resin containing the T-form can form a tough film by three-dimensional crosslinking and polymerization through polymerization due to the effect of moisture. Therefore, a coating having a primer layer formed with a primer composition and a topcoat layer containing silicone containing the T-form can exhibit excellent coating performance not only in initial water repellency but also in weather resistance and water repellency durability. The silicone-based topcoat layer may further contain the M-form (M-unit), D-form (D-unit), and / or Q-form (Q-unit). The silicone-based topcoat layer preferably contains the T-form and D-form. More preferably, the silicone-based topcoat layer contains silicone consisting of the T-form or silicone consisting of the T-form and D-form.

[0067] The silicone-based topcoat layer is formed by a topcoat composition. The topcoat composition preferably contains a silicone resin mainly composed of T-isomer and a second curing catalyst, wherein the blending ratio of the silicone resin is 60 to 100 parts by mass per 100 parts by mass of solid content of the topcoat composition, the heat residue after heat treatment of the topcoat composition at 105°C for 60 minutes is 40% by mass or more, and the kinematic viscosity of the topcoat composition is 2 CS or more. The kinematic viscosity can be measured with an E-type viscometer. The second curing catalyst may be the same as or different from the first curing catalyst.

[0068] The topcoat composition may further contain an M-isomer (M unit), a D-isomer (D unit), and / or a Q-isomer (Q unit). The topcoat composition preferably contains a T-isomer and a D-isomer. The topcoat composition more preferably contains a silicone resin consisting of a T-isomer or a silicone resin consisting of a T-isomer and a D-isomer (hereinafter also referred to as DT resin). The DT resin is composed of a D-isomer with dialkylsiloxane units and a T-isomer with trisiloxane units.

[0069] The D-isomer is (R2SiO). n It has the chemical structure of a structural unit in which two organic groups R are bonded to a silicon atom, and two oxygen atoms are bonded to it. The organic groups R can be, for example, methyl groups or ethyl groups. The D-isomer can be a component of linear or branched polymers, imparting flexibility and stretchability, and improving the flexibility and heat resistance of silicone resins. n is, for example, 4 to 3000.

[0070] T-body is (RSiO 3 / 2 ) n It has the chemical structure of a structural unit in which one organic group R is bonded to a silicon atom, and three oxygen atoms are bonded to it. The organic group R can be, for example, a methyl group, an ethyl group, or a phenyl group. Because the T-isomer has many oxygen atoms, it easily forms a strong three-dimensional structure, which can impart high curability and rigidity, increase hardness and strength after curing, and also improve heat resistance and weather resistance. n is, for example, 2 to 3000.

[0071] Silicone resins containing the T-isomer as the main component may be commercially available products, for example, KC-89 (manufactured by Shin-Etsu Chemical Co., Ltd.), KR-515 (manufactured by Shin-Etsu Chemical Co., Ltd.), KR-500 (manufactured by Shin-Etsu Chemical Co., Ltd.), X-40-9225 (manufactured by Shin-Etsu Chemical Co., Ltd.), US-SG2403 (manufactured by Dow Chemical Corporation), XR31-B1410 (manufactured by Momentive (GE Toshiba Silicone)), MSE-100 (manufactured by Asahi Kasei Wacker Silicone Co., Ltd.), KR-300 (manufactured by Shin-Etsu Chemical Co., Ltd.), KR-255 (manufactured by Shin-Etsu Chemical Co., Ltd.), X-40-9218 (Shin-Etsu Chemical Co., Ltd.) These can include products such as Gaku Kogyo Co., Ltd., X-40-9250 (Shin-Etsu Chemical Co., Ltd.), X-40-9246 (Shin-Etsu Chemical Co., Ltd.), X-40-9227 (Shin-Etsu Chemical Co., Ltd.), X-40-9238 (Shin-Etsu Chemical Co., Ltd.), X-40-2667A (Shin-Etsu Chemical Co., Ltd.), X-40-2756 (Shin-Etsu Chemical Co., Ltd.), X-41-1056 (Shin-Etsu Chemical Co., Ltd.), KR-112 (Shin-Etsu Chemical Co., Ltd.), KR-282 (Shin-Etsu Chemical Co., Ltd.), KR-242A (Shin-Etsu Chemical Co., Ltd.), and KR-9218 (Shin-Etsu Chemical Co., Ltd.).

[0072] The heat residue of the topcoat composition after heat treatment at 105°C for 60 minutes is 40% by mass or more. Such a high amount of heat residue ensures sufficient film thickness (cured film thickness) of the topcoat layer formed by the composition, resulting in good weather resistance and water-repellent durability. If the heat residue is less than 40% by mass, the film thickness of the topcoat layer becomes small, and good weather resistance and water-repellent durability cannot be obtained.

[0073] The heat residue of the topcoat composition after heat treatment at 105°C for 60 minutes is preferably 50% by mass or more, more preferably 60% by mass or more, and even more preferably 70% by mass or more. By having the heat residue of the topcoat composition after heat treatment at 105°C for 60 minutes within the above preferred range, better weather resistance and water-repellent durability can be obtained. The upper limit of the heat residue of the topcoat composition after heat treatment at 105°C for 60 minutes may be, for example, 80% by mass or 90% by mass.

[0074] The kinematic viscosity of the topcoat composition is 2 CS or higher. This high kinematic viscosity allows for wiping while suppressing dripping during application, resulting in a coating film with excellent weather resistance and water-repellent durability.

[0075] The kinematic viscosity of the topcoat composition is preferably 10 CS or more, more preferably 20 CS or more, even more preferably 25 CS or more, and even more preferably 30 CS or more. Having the kinematic viscosity of the topcoat composition within this preferred range helps to further suppress sagging during application and to form a more uniform coating film. The upper limit of the kinematic viscosity of the topcoat composition may be, for example, 50 CS or 40 CS.

[0076] The topcoat composition may contain an organic solvent. The organic solvent contained in the topcoat composition may be non-volatile. The content of the organic solvent contained in the topcoat composition may be, for example, 20% by mass or less, 15% by mass or less, or 12% by mass or less. The topcoat composition does not have to contain an organic solvent, but by containing an organic solvent within the above content range, the heat residue and kinematic viscosity after heat treatment at 105°C for 60 minutes can be easily adjusted to the above range. The organic solvent that may be contained in the topcoat composition can be a hydrocarbon or an alcohol, with hydrocarbons being preferred from the viewpoint of curing speed, and can be, for example, a normal paraffin.

[0077] The topcoat composition may contain an adhesion agent. The adhesion agent can improve the adhesion of the topcoat layer to the undercoat layer. The adhesion agent can be a silane coupling agent, for example, trimethylmethoxysilane, trimethylethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, methylphenyldimethoxysilane, methylphenyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, trimethoxysilane, triethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenylmethylvinylethoxysilane, naphthyltrimethoxysilane, naphthyltriethoxysilane, 1,4-bis(methoxydimethylsilyl)benzene, tetramethoxysilane, tetramethyl Traethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, hexyltrimethoxysilane, octyltriethoxysilane, decyltrimethoxysilane, 1,6-bis(trimethoxysilyl)hexane, vinyltrimethoxysilane, vinyltriethoxysilane, p-styryltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 2-(3,4-Epoxycyclohexyl)ethylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyldimethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-methacryloxypropyldiethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, N-(2-aminoethyl)-3-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldiethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-(vinylbenzyl) Examples of alkoxysilane compounds include -2-aminoethyl-3-aminopropyltrimethoxysilane and its hydrochloride, N-(vinylbenzyl)-2-aminoethyl-3-aminopropylmethyldimethoxysilane and its hydrochloride, 3-isocyanatetopropyltriethoxysilane, tris-(trimethoxysilylpropyl)isocyanurate, 3-ureidopropyltriethoxysilane, 3-chloropropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, and bis(trisethoxysilylpropyl)tetrasulfide, and these can be one or a combination of two or more.

[0078] The topcoat composition may contain pigments. Examples of pigments include luminous pigments, coloring pigments, and extender pigments.

[0079] Examples of luminous pigments include aluminum (including vapor-deposited aluminum), copper, zinc, brass, nickel, glass flakes, aluminum oxide, mica, aluminum oxide coated with titanium oxide and / or iron oxide, and mica coated with titanium oxide and / or iron oxide.

[0080] Examples of coloring pigments include titanium dioxide, zinc oxide, carbon black, molybdenum red, Prussian blue, cobalt blue, azo pigments, phthalocyanine pigments, quinacridone pigments, isoindoline pigments, surene pigments, perylene pigments, dioxazine pigments, and diketopyrrolopyrrole pigments.

[0081] Examples of extender pigments include clay, kaolin, barium sulfate, barium carbonate, calcium carbonate, talc, silica, and alumina white.

[0082] The topcoat composition may contain silicone oil. Silicone oil is a component that imparts non-stick and water-repellent properties to the coating film. Silicone oil has a linear main chain, for example, a repeating polysiloxane structure (-(SiO) nIt has -). Examples of silicone oils include straight silicone oils (unmodified silicone oils) such as polydimethylsiloxane, polymethylphenylsiloxane, and polydiphenylsiloxane. In addition to straight silicone oils, modified silicone oils are also available in which the terminal and / or side chains of the main chain are modified with alkyl groups, alkenyl groups (including vinyl groups), alkynyl groups, phenyl groups, ionic groups, etc. Examples of ionic groups include anionic groups such as mercapto groups and cationic groups such as amino groups. These silicone oils can be used alone or in combination of two or more. Preferably, straight silicone oils are used as silicone oils, and more preferably, polydimethylsiloxane. Commercially available silicone oils are used, such as the KF-96 series (manufactured by Shin-Etsu Chemical Co., Ltd.), KF-965 series (manufactured by Shin-Etsu Chemical Co., Ltd.), SH200 series (manufactured by Dow Chemical Japan Co., Ltd.), TSF451 series (manufactured by Momentive Performance Materials Japan Co., Ltd.), and YF-33 series (manufactured by Momentive Performance Materials Japan Co., Ltd.). When the topcoat composition contains silicone oil, crack resistance and water repellency are improved, slipperiness is provided, and a scratch-preventive effect is granted.

[0083] However, the water-repellent durability can be further improved when the topcoat composition applied on the undercoat layer formed with this undercoat composition has a low or no silicone oil content.

[0084] The silicone oil content in the topcoat composition is preferably 5% by mass or less, more preferably 3% by mass or less, even more preferably 1% by mass or less, and even more preferably substantially 0% by mass, relative to the total amount of the topcoat composition. A topcoat composition applied on a primer layer formed with this primer composition can exhibit superior water-repellent durability by having a low silicone oil content or by not containing any silicone oil at all.

[0085] The thickness of the topcoat layer formed with the topcoat composition (cured thickness) may be, for example, 0.01 to 1000 μm, 0.1 to 750 μm, 1 to 500 μm, 10 to 250 μm, or 50 to 100 μm.

[0086] The substrates to which this primer composition can be applied are not particularly limited and may include inorganic materials, organic materials, hybrid materials of inorganic and organic materials, and the like.

[0087] Examples of inorganic materials include metal materials such as iron, aluminum, brass, copper, tinplate, stainless steel, galvanized steel, zinc alloys (Zn-Al, Zn-Ni, Zn-Fe, etc.), plated steel, glass, cement, and concrete.

[0088] Examples of organic materials include acrylic resins such as polymethyl methacrylate, polyester resins such as polyethylene terephthalate, polyethylene naphthalate, poly-1,4-cyclohexanedimethylene terephthalate, polyethylene-1,2-diphenoxyethane-4,4'-dicarboxylate, and polybutylene terephthalate, epoxy resins such as commercially available products like Epicote (trade name: manufactured by Yuka Shell Epoxy Co., Ltd.), polycarbonate resins, polyimide resins, novolac resins, phenolic resins, acrylonitrile-butadiene-styrene (ABS) resins, vinylidene chloride resins, polyurethane resins, cellulose esters (e.g., triacetylcellulose, diacetylcellulose, propionylcellulose, butyrylcellulose, acetylpropionylcellulose, nitrocellulose, etc.), polyamides, polystyrene (e.g., syndiotactic polystyrene), polyolefins (e.g., polypropylene, polyethylene, polymethylpentene, etc.), polysulfones, polyethersulfones, polyarylates, polyetherimides, and polyetherketones. Organic materials may also contain pigments and / or fibers as part of their composition. Examples of pigments include calcium carbonate, silica, barium sulfate, barium carbonate, talc, clay, kaolin, aluminum hydroxide, magnesium oxide, and aluminum oxide. Examples of fibers include glass fibers, aramid fibers, carbon fibers, and cellulose fibers. Various fiber-reinforced plastic materials are included in the above-mentioned organic materials.

[0089] Examples of hybrid materials combining inorganic and organic materials include siloxane-based hybrid materials such as polysiloxanes and organosiloxanes; hybrid polymers; composite materials of polyarylate and silica; composite materials of polyimide and silica; composite materials of fluororesin and inorganic fillers; composite materials of bioceramics and organic polymers; and composite materials of nanocellulose and inorganic nanoparticles.

[0090] The base material may be one of the above materials that has been plated. Examples of plating include chromium plating, nickel plating, gold plating, silver plating, copper plating, and zinc plating, and may be a single type of plating or a combination of two or more types of plating.

[0091] This disclosure also relates to a primer layer for a silicone-based topcoat (also referred to as the primer layer) formed with the above-mentioned primer composition. The primer layer functions as a primer layer for a silicone-based topcoat, and a coating comprising the primer layer and the silicone-based topcoat on top of it can exhibit excellent weather resistance and water-repellent durability.

[0092] This disclosure also relates to a laminated structure comprising a substrate and a primer layer on the substrate formed of the above-mentioned primer composition for a silicone-based topcoat layer. The laminated structure may be a coating further comprising a silicone-based topcoat layer on the primer layer.

[0093] The silicone-based topcoat layer is a topcoat composition containing a silicone resin mainly composed of T-isomer and a second curing catalyst, wherein the blending ratio of the silicone resin is 60 parts by mass or more and less than 100 parts by mass per 100 parts by mass of the solid content of the topcoat composition, the heat residue after heat treatment at 105°C for 60 minutes is 40% by mass or more, and the kinematic viscosity as a coating agent is 2 CS or more, and the topcoat composition is cured.

[0094] This disclosure also relates to a method for manufacturing a laminated structure, comprising applying a primer composition for forming a primer layer for a silicone-based topcoat layer onto a substrate to form a primer layer for a silicone-based topcoat layer, wherein the primer composition contains a sulfur-based functional group-containing silicone, a first curing catalyst, and a volatile organic solvent, the proportion of the sulfur-based functional group-containing silicone is 70 parts by mass or more and less than 100 parts by mass per 100 parts by mass of the solid content of the primer composition, and the heat residue after heat treatment at 105°C for 60 minutes is 0.25% by mass or more and 20% by mass or less.

[0095] The method of applying the primer composition to the substrate is not particularly limited and can be done by conventional methods, such as brush application or spray coating, which can be appropriately selected depending on the purpose and application. Preferably, it can be applied by rubbing it into the substrate using a sponge. For example, the primer composition can be impregnated into a sponge and then rubbed onto the surface with the sponge.

[0096] After applying the undercoat composition to the substrate, it may be dried at any temperature and humidity. The drying temperature is preferably 0 to 40°C, more preferably 10 to 35°C, and even more preferably 20 to 30°C. The drying humidity is preferably 10 to 100% RH, more preferably 20 to 85% RH, and even more preferably 30 to 70% RH. The drying time can also be any time, but is preferably 10 to 120 minutes, more preferably 15 to 95 minutes, and even more preferably 20 to 70 minutes. By drying under the above drying conditions, an undercoat layer with more stable weather resistance and water repellency can be formed when the topcoat layer is formed.

[0097] Preferably, a silicone-based topcoat layer can be formed by applying a topcoat composition containing a silicone resin mainly composed of T and a second curing catalyst onto the undercoat layer. The method of applying the topcoat composition onto the undercoat layer is not particularly limited and can be done by conventional methods, but preferably, it can be applied by rubbing it into the undercoat layer using a sponge.

[0098] Preferably, the proportion of the silicone resin is 60 parts by mass or more and less than 100 parts by mass per 100 parts by mass of the solid content of the topcoat composition, the heat residue of the topcoat composition after heat treatment at 105°C for 60 minutes is 40% by mass or more, and the kinematic viscosity of the topcoat composition is 2 CS or more.

[0099] Preferably, the silicone oil content of the topcoat composition is 5% by mass or less.

[0100] Preferably, the topcoat composition is applied and then wiped off. The wiping can be done using a microfiber cloth or the like until any unevenness in the coating is no longer visible. [Examples]

[0101] (Example 1) (Preparation of primer composition) A primer composition was prepared by mixing 2% by mass of 3-triethoxylylthiopropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., X-12-1056ES, monomer with a protecting group), a sulfide-containing silicone, 0.25% by mass of titanium tetraisopropoxide as a curing catalyst, and 48.90% by mass of n-hexane and 48.85% by mass of ethanol as volatile organic solvents. The content of 3-triethoxylylthiopropyltrimethoxysilane per 100 parts by mass of solids in the primer composition was 88.9% by mass.

[0102] (Preparation of topcoat composition) A topcoat composition was prepared by mixing 87.66% by mass of DT resin (Shin-Etsu Chemical Co., Ltd., X-40-9250), 0.87% by mass of titanium tetraisopropoxide, and 11.47% by mass of normal paraffin. The kinematic viscosity of the prepared topcoat composition was 34.6 CS. The kinematic viscosity was measured using an E-type viscometer (TV-100EH, Toki Sangyo Co., Ltd.) under the following conditions: temperature 25°C, rotation speed 30 rpm, rotor code: 1°34'xR24, and measurement range: H.

[0103] (Construction) As test specimens, a substrate with hard chrome plating (plated test specimen; 200 mm x 70 mm) as shown in Figure 7 was used. As a pretreatment, it was polished with an abrasive (Crystal Process Co., Ltd., One-Shot Mirror Finish) and then degreased with ethanol.

[0104] Under conditions of 25±2°C and 55%RH humidity, the prepared primer composition was applied to a pre-treated plated test piece using a sponge, and then dried for 30 minutes to form a primer layer. The residual heat of the primer composition after heat treatment at 105°C for 60 minutes was 0.85 parts by mass. Next, the prepared topcoat composition was applied over the primer layer using a sponge, and wiped with a microfiber cloth until evenness was achieved to form a topcoat layer. The residual heat of the topcoat composition after heat treatment at 105°C for 60 minutes was 76.8 parts by mass.

[0105] (Comparative Example 1) Under conditions of 25±2℃ and 55%RH humidity, a plated test piece pre-treated in the same manner as in Example 1 was directly applied to the plated test piece using a sponge, without applying the primer composition first. The topcoat composition, prepared in the same manner as in Example 1, was then wiped with a microfiber cloth until evenness was achieved, and allowed to dry for 30 minutes to form the topcoat layer.

[0106] (Comparative Example 2) A plated test piece was prepared in the same manner as in Example 1, without applying a coating.

[0107] (Comparative Example 3) Similar to Example 1, a topcoat composition and a primer composition were prepared, and the topcoat composition and the primer composition were mixed to prepare a mixed composition.

[0108] (Construction) Under conditions of 25±2℃ and 55%RH humidity, the prepared mixed composition was applied to a plated test piece that had been pre-treated in the same manner as in Example 1, using a sponge. The mixture was then wiped with a microfiber cloth until there were no uneven areas, and allowed to dry for 30 minutes to form a single coating layer.

[0109] (Weathering resistance test (exposure test)) The plated test pieces coated in Example 1, Comparative Example 1, and Comparative Example 3, as well as the plated test piece prepared in Comparative Example 2, were subjected to an exposure test in an outdoor environment for 5 months.

[0110] Table 1 shows the evaluation results for the workability, initial water repellency, water repellency after exposure testing (post-exposure water repellency), and water repellency durability of the compositions in Example 1 and Comparative Examples 1-3.

[0111] The workability was evaluated as follows: a score of 3 was given to products that could be applied and wiped off without any problems; a score of 2 was given to products that were heavy but could be wiped off; and a score of 1 was given to products that were very heavy and could not be wiped off.

[0112] Water-repellency durability is a test to confirm car wash durability. A 50mm x 50mm urethane sponge containing a neutral detergent was attached to a friction and abrasion testing machine (Shinto Kagaku Co., Ltd., Tribogear TYPE-14FW model), and the water-repellency durability was evaluated by rubbing each test piece under the following test conditions.

[0113] The test conditions for the friction and wear test are schematically shown in Figure 5, with a constant load and surface pressure of 0.24 N / cm². 2 (Load 600g, sponge area: 25cm) 2 The test was conducted using a neutral detergent (Crystal Process Co., Ltd., Crystal Shampoo) with a speed of 100 mm / second (the test stand with the test specimen reciprocated at a constant speed), 1000 reciprocating cycles. Separate test specimens were prepared for each of the exposure and friction / wear tests.

[0114] Initial water repellency, water repellency after exposure, and water repellency durability were evaluated using a contact angle measuring device (Kyowa Interface Science Co., Ltd., DM700). The water volume was set to 1.0 μL, and using the droplet method, samples with a contact angle of 95° or greater (analyzed by the θ / 2 method) were evaluated in three stages: ○, less than 95° to 85° or greater (△), and less than 85° (×). ○ and △ were considered pass. Figure 4 shows photographs observing the water repellency state that roughly corresponds to ○, △, and ×.

[0115] The composition prepared in Example 1 showed good workability, and the coated plated test specimens exhibited excellent water repellency and water repellency durability after exposure. The plated test specimens in Comparative Example 2 had low initial water repellency and low water repellency durability. The plated test specimens coated in Comparative Example 1 had good initial water repellency but low water repellency durability. The plated test specimens coated with a single layer of the mixed composition in Comparative Example 3 also had good initial water repellency but low water repellency durability.

[0116] [Table 1]

[0117] (Example 2) Except for using a trimethoxysilane (Shin-Etsu Chemical Co., Ltd., X-41-1805S, a methoxy-ethoxy group-containing oligomer) that has a mercapto group and no protecting group instead of X-12-1056ES, a primer composition was prepared in the same manner as in Example 1, and an exposure test was performed by forming a two-layer coating of a primer layer and a topcoat layer on the surface of a plated test piece.

[0118] (Example 3) Except for using 3-mercaptopropyltrimethoxysilane (Dow Chemical, Z-6062, monomer) which has a mercapto group but no protecting group, instead of X-12-1056ES, a primer composition was prepared in the same manner as in Example 1, and a two-layer coating consisting of a primer layer and a topcoat layer was formed on the surface of a plated test piece, and an exposure test was performed.

[0119] (Comparative Examples 4-8) Except for using a trimethoxysilane having a glycide group (Shin-Etsu Chemical Co., Ltd., KBM-403, glycide monomer), a trimethoxysilane having an amino group (Shin-Etsu Chemical Co., Ltd., KBM-903, amino monomer), a trimethoxysilane having an alkyl group (Shin-Etsu Chemical Co., Ltd., KBM-3033, alkyl monomer, n-propyltrimethoxysilane), a trimethoxysilane having a C3 alkyl group and a protecting group (Shin-Etsu Chemical Co., Ltd., KBM-3033, alkyl monomer (C3)), and polysilazane (Terada, TMGP-0021) instead of X-12-1056ES, a primer composition was prepared in the same manner as in Example 1. A two-layer coating, a primer layer and a topcoat layer, was formed on the surface of a plated test piece, and the water repellency and water repellency durability after exposure were evaluated.

[0120] Table 2 shows the evaluation results for workability, initial water repellency, water repellency after exposure, and water repellency durability of the compositions in Examples 2-3 and Comparative Examples 4-8. The compositions prepared in Examples 2-3 showed good workability, and the coated plated test pieces showed excellent water repellency after exposure.

[0121] The compositions prepared in Comparative Examples 4-8 showed good workability, but the water repellency and water repellency durability of the coated test specimens after exposure were low. [Table 2]

[0122] (Comparative Example 9) Except for not containing a curing catalyst, a primer composition was prepared in the same manner as in Example 1, and a two-layer coating, a primer layer and a topcoat layer, was formed on the surface of a plated test piece to evaluate its water-repellent durability. The portion without the curing catalyst was adjusted by increasing the content of n-hexane and ethanol in the same proportions.

[0123] Table 3 shows the evaluation results for the workability, initial water repellency, and water repellency durability of the composition in Comparative Example 9. The composition prepared in Comparative Example 9 showed good workability, but the water repellency durability of the coated test specimens was low.

[0124] [Table 3]

[0125] (Example 4) A topcoat composition was prepared in the same manner as in Example 1, except that 5% by mass of Cylaprene FM-9915 (manufactured by JNC Corporation) silicone oil was added. A two-layer coating, a base coat and a top coat, was formed on the surface of the plated test piece, and the water repellency and water repellency durability after exposure were evaluated. The amount of normal paraffin was adjusted to compensate for the addition of silicone oil.

[0126] (Comparative Example 10) Except for using a polysilazane-containing coating agent (Terada Co., Ltd., TMGP-0021) as the topcoat composition, a two-layer coating consisting of a base coat and a top coat was formed on the surface of the plated test piece in the same manner as in Example 1, and the water repellency and water repellency durability after exposure were evaluated.

[0127] Table 4 shows the evaluation results for workability, initial water repellency, water repellency after exposure, and water repellency durability of the compositions in Example 4 and Comparative Example 10. The compositions prepared in Example 4 and Comparative Example 10 both showed good workability, but the plated test piece with a topcoat layer formed using the topcoat agent of Example 4 showed slightly lower water repellency after exposure compared to the plated test piece applied in Example 1, and the plated test piece with a topcoat layer formed using the topcoat agent of Comparative Example 10 showed low water repellency after exposure.

[0128] [Table 4]

[0129] (Example 5) As a base material, instead of a plated test piece, an aluminum plate A1050 (test piece; 200 mm × 75 mm) as shown in Figure 6 was used, and the primer composition and topcoat composition were prepared in the same manner as in Example 1, except that the surface treatment involved degreasing with acetone. A two-layer coating, a primer layer and a topcoat layer, was formed on the surface of the aluminum test piece.

[0130] (Comparative Example 11) Aluminum plate A1050 test specimens were prepared in the same manner as in Example 5, without coating.

[0131] Table 5 shows the evaluation results for workability, initial water repellency, water repellency after exposure, and water repellency durability of the compositions in Example 5 and Comparative Example 11.

[0132] The composition prepared in Example 5 showed good workability, and the coated aluminum test specimens exhibited excellent water-repellent durability. Comparative Example 11, which lacked a primer layer, had poor water-repellent durability.

[0133] [Table 5]

[0134] (Comparative Example 12, Examples 6-7) Except for the amount of X-12-1056ES as the sulfur-based functional group-containing silicone in the undercoat composition being 0.5% by mass, 1% by mass, and 5% by mass, undercoat compositions were prepared in the same manner as in Example 1, and a two-layer coating of an undercoat layer and a topcoat layer was formed on the surface of an aluminum test piece in the same manner as in Example 5, and the water repellency and water repellency durability after exposure were evaluated. The increase or decrease in the content of X-12-1056ES was adjusted by increasing or decreasing the content of n-hexane and ethanol in the same proportions.

[0135] Table 6 shows the evaluation results for the workability, initial water repellency, water repellency after exposure, and water repellency durability of the compositions in Comparative Example 12 and Examples 6-7. The composition prepared in Comparative Example 12 showed good workability, but the water repellency durability of the coated aluminum test piece was low. The composition prepared in Example 6 showed good workability, and the coated aluminum test piece showed excellent water repellency after exposure and water repellency durability. The composition prepared in Example 7 showed workability that was heavy but could be wiped off, and the coated aluminum test piece showed excellent water repellency after exposure and water repellency durability.

[0136] [Table 6]

[0137] (Example 8) Except for preparing the topcoat composition by mixing 47.66% by mass of DT resin (Shin-Etsu Chemical Co., Ltd., X-40-9250), 0.87% by mass of titanium tetraisopropoxide, and 51.47% by mass of normal paraffin, the same procedure as in Example 1 was used to form a two-layer coating of a base coat and a topcoat on the surface of a plated test piece, and the water repellency and water repellency durability after exposure were evaluated. The kinematic viscosity of the prepared topcoat composition was 2.2 CS, and the heat residue after heat treatment at 105°C for 60 minutes was 43.7 parts by mass.

[0138] Table 7 shows the evaluation results for the workability, initial water repellency, water repellency after exposure, and water repellency durability of the composition in Example 8. The composition prepared in Example 8 showed good workability. Plated test pieces coated with the composition prepared in Example 8 showed excellent water repellency after exposure, and although the water repellency durability was slightly lower than that of Example 1, it was still good.

[0139] [Table 7]

[0140] (Examples 9-12) Except for using curing catalyst amounts of 0.01% by mass, 0.1% by mass, 0.5% by mass, and 1% by mass, primer compositions were prepared in the same manner as in Example 1. A two-layer coating, a primer layer and a topcoat layer, was formed on the surface of an aluminum test piece in the same manner as in Example 5, and the water repellency and water repellency durability after exposure were evaluated. The difference in curing catalyst amount was adjusted by increasing or decreasing the content of n-hexane and ethanol in the same proportions.

[0141] Table 8 shows the evaluation results for the workability, initial water repellency, water repellency after exposure, and water repellency durability of the compositions in Examples 9 to 12. The compositions prepared in Examples 9 to 12 showed good workability, and the coated aluminum test pieces showed excellent water repellency after exposure and water repellency durability.

[0142] [Table 8]

[0143] (Example 13) As the substrate, a black automotive coating test piece (painted test piece; 200 mm x 100 mm) as shown in Figure 8 was used. Except for the pretreatment, which involved polishing with an abrasive (Crystal Process Co., Ltd., One-Shot Mirror Finish) and then degreasing with ethanol, a two-layer coating consisting of a base coat and a top coat was formed in the same manner as in Example 1, and the water repellency and water repellency durability after exposure were evaluated.

[0144] Table 9 shows the evaluation results for the workability, initial water repellency, water repellency after exposure, and water repellency durability of the composition in Example 13. The composition prepared in Example 13 showed good workability, and the coated test specimens showed excellent water repellency after exposure and water repellency durability.

[0145] [Table 9]

[0146] (Examples 14-18) Except for using resin test pieces made of PC (polycarbonate), ABS, acrylic, PP (polypropylene), and PE (polyethylene) as substrates (each test piece size: 200 mm x 70 mm), two-layer coatings consisting of a primer layer and a topcoat layer were formed in the same manner as in Example 1, and weather resistance and water-repellent durability were evaluated.

[0147] Table 10 shows the evaluation results for the workability, initial water repellency, water repellency after exposure, and water repellency durability after friction and abrasion testing of the compositions in Examples 14-18. The compositions prepared in Examples 14-18 showed good workability, and the coated test pieces showed excellent water repellency durability.

[0148] [Table 10]

[0149] (Example 19 and Comparative Example 13) As a base material, a chrome-plated part (plated part test piece; manufactured by Jet Inoue Co., Ltd., truck side mirror cover, 200 mm x 320 mm), which is a part used in actual vehicle bodies, was used. As a pretreatment, it was polished with an abrasive (manufactured by Crystal Process Co., Ltd., Ippatsu Koshin), and then degreased with ethanol. A two-layer coating consisting of a base coat and a top coat was formed on the left side of the plated part test piece in the same manner as in Example 1 (Example 19), and a single-layer coating consisting only of a top coat was formed on the right side of the plated part test piece in the same manner as in Comparative Example 1 (Comparative Example 13). Water repellency after exposure (only water repellency after exposure was evaluated because the plated part test piece was a curved surface) was evaluated.

[0150] The formation of the two-layer coating (undercoat and topcoat) in Example 19 and the formation of the single-layer coating (topcoat only) in Comparative Example 13 were carried out specifically as follows. The plated part test piece was divided into left and right regions, and the right region of the plated part test piece was covered with masking tape. Next, the prepared undercoat composition was applied to the left region to form the undercoat layer in Example 19. Then, the masking tape was removed and the prepared topcoat composition was applied to the entire surface to form a two-layer coating (undercoat and topcoat) in the left region and a single-layer coating (topcoat only) in the right region. Figure 1 shows photographs of the appearance of the plated part test piece with the coatings of Example 19 and Comparative Example 13.

[0151] Figure 2 shows photographs evaluating the water-repellent durability of plated parts coated in Example 19 and Comparative Example 13 after 5 months of exposure. Figure 3 shows a magnified photograph of Figure 2. As can be seen from Figures 2 and 3, the left region of the plated parts coated in Example 19 showed good water repellency even after 5 months of exposure, while the right region of the plated parts coated in Comparative Example 13 showed a decrease in water repellency after 5 months of exposure. Furthermore, the plated parts coated in Example 19 and Comparative Example 13 showed almost the same water repellency after 1 month of exposure as after 5 months of exposure.

[0152] Table 11 shows the evaluation results for the workability, initial water repellency, water repellency after exposure, and water repellency durability after friction and abrasion testing of the compositions in Example 19 and Comparative Example 13. The composition prepared in Example 19 showed good workability, and the coated test specimens showed excellent water repellency durability. The test specimens coated in Example 13 showed low water repellency after exposure.

[0153] [Table 11]

[0154] (Comparative Example 14) Except for using trimethoxysilane (OFS-6341, alkyl monomer (C8)) having an alkyl group with 8 carbon atoms and a protecting group instead of X-12-1056ES, a primer composition was prepared in the same manner as in Example 1, and a two-layer coating consisting of a primer layer and a topcoat layer was formed on the surface of an aluminum test piece in the same manner as in Example 5, and the weather resistance and water-repellent durability were evaluated.

[0155] (Comparative Example 15) Except for using a trimethoxysilane (Dow Chemical Company, Z-6210, alkyl monomer (C10)) having a C10 alkyl group and a protecting group instead of X-12-1056ES, a primer composition was prepared in the same manner as in Example 1, and a two-layer coating consisting of a primer layer and a topcoat layer was formed on the surface of an aluminum test piece in the same manner as in Example 5, and the water repellency and water repellency durability after exposure were evaluated.

[0156] Table 12 shows the evaluation results for the workability, initial water repellency, water repellency after exposure, and water repellency durability of the compositions in Comparative Examples 14-15. The compositions prepared in Comparative Examples 14-15 showed good workability, but the water repellency durability of the coated test specimens was low.

[0157] [Table 12]

[0158] (Example 20: Evaluation without wiping) Except for not wiping off the topcoat composition after application, two layers of coating were formed on the surface of the plated test piece in the same manner as in Example 1, and the water repellency and water repellency durability after exposure were evaluated. The test piece coated in Example 20 showed slightly lower effectiveness compared to Example 1, but still exhibited good water repellency and water repellency durability after exposure.

Claims

1. A primer composition for forming a primer layer for a silicone-based topcoat layer, Sulfur-based functional group-containing silicone, First curing catalyst, and Volatile organic solvents It contains, The proportion of the sulfur-based functional group-containing silicone is 70 parts by mass or more and less than 100 parts by mass per 100 parts by mass of the solid content of the undercoat composition. A primer composition having a heat residue of 0.25% by mass or more and 20% by mass or less after heat treatment at 105°C for 60 minutes.

2. The primer composition according to claim 1, wherein the content of the first curing catalyst is 0.0025 to 5 parts by mass per 100 parts by mass of the primer composition.

3. The primer composition according to claim 1, wherein the content of the volatile organic solvent is more than 80 parts by mass and less than 100 parts by mass per 100 parts by mass of the primer composition.

4. The primer composition according to any one of claims 1 to 3, wherein the silicone-based topcoat layer comprises a T-body.

5. The topcoat composition for forming the aforementioned silicone-based topcoat layer is Silicone resin containing T-body, and Second curing catalyst It contains, The proportion of the silicone resin is 60 parts by mass or more and less than 100 parts by mass per 100 parts by mass of the solid content of the topcoat composition. The heat residue of the topcoat composition after heat treatment at 105°C for 60 minutes is 40% by mass or more. The kinematic viscosity of the topcoat composition is 2 CS or higher. The primer composition according to claim 1.

6. The undercoat composition according to claim 5, wherein the silicone oil content of the topcoat composition is 5% by mass or less.

7. A primer layer for a silicone-based topcoat layer, formed with the primer composition described in claim 1.

8. Substrate, and A primer layer for a silicone-based topcoat layer formed on the substrate with the primer composition according to claim 1. A laminated structure including a laminated structure.

9. The laminated structure according to claim 8, further comprising a silicone-based topcoat layer on the aforementioned undercoat layer.

10. A method for manufacturing a laminated structure, comprising applying an undercoat composition for forming an undercoat layer for a silicone-based topcoat layer onto a substrate to form an undercoat layer for a silicone-based topcoat layer, The aforementioned primer composition Sulfur-based functional group-containing silicone, First curing catalyst, and Volatile organic solvents It contains, The proportion of the sulfur-based functional group-containing silicone is 70 parts by mass or more and less than 100 parts by mass per 100 parts by mass of the solid content of the undercoat composition. The residual heat after heating at 105°C for 60 minutes is 0.25% by mass or more and 20% by mass or less. A method for manufacturing a laminated structure.

11. The method for manufacturing a laminated structure according to claim 10, further comprising applying a topcoat composition containing a silicone resin including a T-body and a second curing catalyst onto the undercoat layer to form the silicone-based topcoat layer.

12. The proportion of the silicone resin is 60 parts by mass or more and less than 100 parts by mass per 100 parts by mass of the solid content of the topcoat composition. The heat residue of the topcoat composition after heat treatment at 105°C for 60 minutes is 40% by mass or more. The kinematic viscosity of the topcoat composition is 2 CS or higher. A method for manufacturing a laminated structure according to claim 11.

13. The method for manufacturing a laminated structure according to claim 11, wherein the silicone oil content of the topcoat composition is 5% by mass or less.

14. A method for manufacturing a laminated structure according to any one of claims 11 to 13, wherein the topcoat composition is applied and then wiped off.

Images