High adhesion coating composition

Abstract

It is an object of the present invention to provide a high adhesion coating composition which is excellent in production suitability and is excellent in the balance among high adhesion to a resin substrate, particularly a resin substrate made of a polypropylene resin, water resistance, cut resistance, acid resistance, chemical resistance and high surface hardness, a coating method of the high adhesion coating composition, and a high adhesion laminate having a high adhesion coating layer formed by using the high adhesion coating composition.SOLUTION: A high-adhesion coating composition for a resin substrate, comprising silica fine particles, a polyolefin-based resin, and a solvent, wherein the polyolefin-based resin comprises a chlorinated and / or maleic anhydride-modified polyolefin, has a softening point of 50 to 100 °C, and has a silica fine particle / polyolefin-based resin mass ratio of 0.2 to 20.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a highly adhesive coating composition that has excellent adhesion to a resin substrate, a coating method for the highly adhesive coating composition, and a highly adhesive laminate that is formed using the highly adhesive coating composition and includes a highly adhesive coating layer that has durability, acid resistance, chemical resistance, high hardness, and cut resistance. The highly adhesive coating composition of the present invention can form a highly adhesive coating layer with high adhesion on a resin substrate made of a polypropylene-based resin, which is usually considered difficult to form. [Background technology]

[0002] Electronic devices and automobiles use electrical and electronic components that use glass, resin, and metal lead frames, and require bonding and adhesion between various metals, resins, and metal-plated surfaces. Patent Document 1 discloses a hot melt adhesive composition containing a polyolefin for producing nonwoven fabric products such as nonwoven fabric laminates. Patent Document 2 discloses an adhesive composition containing a copolymer of alkyl-substituted N,N-diphenylacrylamide and a (meth)acrylic acid ester, which has excellent adhesive properties to a variety of resins. Patent Document 3 discloses a composition containing a chlorine-free poly-α-olefin having a silane group and a ketone-based resin (ketone resin, ketone / aldehyde resin, urea / aldehyde resin, or a hydride thereof) for improving the adhesion of a coating agent to a resin substrate. However, these have low compatibility with polypropylene resins and poor adhesion, and therefore have not yet shown sufficient performance. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Table 2021-536521 [Patent Document 2] WO2020 / 262423 [Patent Document 3] Japanese Patent Application Laid-Open No. 2008-069354 Summary of the Invention [Problem to be solved by the invention]

[0004] The present invention aims to provide a highly adhesive coating composition that has excellent manufacturability and an excellent balance of high adhesion to resin substrates, particularly resin substrates made of polypropylene-based resins, water resistance, cut resistance, acid resistance, chemical resistance, and high surface hardness; a coating method for the highly adhesive coating composition; and a highly adhesive laminate having a highly adhesive coating layer formed using the highly adhesive coating composition. Furthermore, the present invention aims to provide a highly adhesive laminate having various functional layers on the highly adhesive coating layer, thereby providing hydrophilicity, water repellency, antibacterial properties, further high surface hardness, and antireflection properties. [Means for solving the problem]

[0005] As a result of extensive research, the present inventors have discovered that a highly adhesive coating composition for resin substrates, which contains silica microparticles, a specific polyolefin resin, and a solvent, can solve the above-mentioned problems. That is, the present invention is characterized by the following points. [1] A highly adhesive coating composition for resin substrates, comprising silica fine particles, a polyolefin resin, and a solvent, the polyolefin resin is a chlorinated and / or maleic anhydride-modified polyolefin and has a softening point of 50 to 100°C; The mass ratio of silica particles to polyolefin resin is 0.2 to 20. A highly adhesive coating composition. [2] The highly adhesive coating composition according to [1], wherein the silica fine particles are chain-like silica or pearl necklace-like silica. [3] The highly adhesive coating composition according to [1], further comprising an adhesion promoter and / or a curing accelerator catalyst. [4] The high adhesion coating composition further contains an adhesion imparting agent, The highly adhesive coating composition according to [1], wherein the adhesion promoter is at least one selected from the group consisting of alkoxysilanes, silane coupling agents, titanium coupling agents, and silane / titanium condensates. [5] A coating method for coating a resin substrate with the highly adhesive coating composition according to any one of [1] to [4], The coating method includes one selected from the group consisting of a dip coating method, a spin coating method, and a spray coating method. A coating method comprising: [6] A high-adhesion laminate comprising a substrate layer and a high-adhesion coating layer, the substrate layer is a layer made of a resin substrate, The highly adhesive coating layer is a layer made of the highly adhesive coating composition according to any one of [1] to [4], and is laminated adjacent to the resin substrate. A highly adhesive laminate. [7] A high-adhesion laminate further having a functional layer on the high-adhesion coating layer, The functional layer is one or more layers selected from the group consisting of a hydrophilic layer, a water-repellent layer, an antibacterial layer, a hard coat layer, and an anti-reflection layer. The high-adhesion laminate according to [6], [Effects of the Invention]

[0006] According to the present invention, it is possible to provide a highly adhesive coating composition that has excellent manufacturability and an excellent balance of high adhesion to resin substrates, particularly resin substrates made of polypropylene-based resins, water resistance, cut resistance, acid resistance, chemical resistance, and high surface hardness; a coating method for the highly adhesive coating composition; and a highly adhesive laminate having a highly adhesive coating layer formed using the highly adhesive coating composition. Furthermore, by having a functional layer on the high-adhesion coating layer, it is possible to provide a high-adhesion laminate that has additional hydrophilicity, water repellency, antibacterial properties, higher surface hardness, and anti-reflection properties. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a cross-sectional view of a high-adhesion laminate of the present invention. [Figure 2] FIG. 3 is a cross-sectional view of another embodiment of a high-adhesion laminate of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0008] The following describes in detail the embodiments of the present invention. The following description of the components is an example of an embodiment of the present invention, and the present invention is not limited to these details as long as it does not deviate from the gist of the present invention.

[0009] <Highly adhesive coating composition> The highly adhesive coating composition of the present invention is for use on resin substrates and comprises silica fine particles and a specific The composition contains a polyolefin resin and a solvent. The highly adhesive coating composition of the present invention can form a highly adhesive coating layer having high adhesion to other layers such as a resin substrate. For example, when the resin substrate is made of a polypropylene-based resin, the adhesion to the surface of the resin substrate is generally poor. However, the high-adhesion coating composition of the present invention can form a high-adhesion coating layer with excellent adhesion even when the resin substrate is made of a polypropylene-based resin.

[0010] The total content of solids (non-volatile components) such as silica fine particles and polyolefin resin in the highly adhesive coating composition is preferably 0.1% by mass or more and 20% by mass or less, more preferably 0.5% by mass or more and 5% by mass or less. If the content is less than the above range, it is likely to be difficult to form a highly adhesive coating layer with a sufficient thickness, and if the content is more than the above range, the coatability is likely to be poor.

[0011] The content of silica fine particles in the solids (non-volatile content) of the high-adhesion coating composition is preferably 20% by mass or more and 95% by mass or less, more preferably 40% by mass or more and 80% by mass or less. If the content is less than the above range, the adhesion is likely to be insufficient, and if the content is more than the above range, the coatability is likely to be poor and the high-adhesion coating layer is likely to be brittle.

[0012] The content of the polyolefin resin in the solids (non-volatile content) of the high-adhesion coating composition is preferably 5% by mass or more and 70% by mass or less, and more preferably 15% by mass or more and 60% by mass or less. If the content is less than the above range, the adhesion is likely to be insufficient, and if the content is more than the above range, the coatability is likely to be poor and the high-adhesion coating layer is likely to be brittle.

[0013] The mass ratio of silica fine particles to polyolefin resin is preferably 0.2-20, more preferably 0.5-15, and even more preferably 0.8-10. If the mass ratio of silica fine particles to polyolefin resin is smaller than the above range, it is difficult to form sufficient unevenness at the adhesion interface, resulting in insufficient adhesion. If the mass ratio is larger than the above range, it is difficult to form a film, resulting in poor paintability.

[0014] Furthermore, a functional layer composition can be applied onto the highly adhesive coating layer made of the highly adhesive coating composition of the present invention to form a functional layer depending on the purpose. The functional layer is, for example, a hydrophilic layer, a water-repellent layer, an antibacterial layer, a hard coat layer, an anti-reflection layer, etc., and may be one or more types selected from the group consisting of these.

[0015] The highly adhesive coating composition of the present invention may further contain an adhesion promoter, a curing-accelerating catalyst, etc., depending on the purpose. Furthermore, the high-adhesion coating composition of the present invention may further contain, as necessary, a wetting agent, a viscosity material (thickener), a surface conditioning material, a coloring material (pigment, dye), an antistatic material, a conductivity imparting agent, an antibacterial and antiviral material, silicates, various fillers, and the like, within a range that does not adversely affect the properties of the high-adhesion coating composition or the high-adhesion coating layer.

[0016] The highly adhesive coating composition of the present invention can achieve the above-mentioned high adhesion by virtue of the polyolefin resin contained therein exhibiting strong interaction with other layers such as a resin substrate. Furthermore, when the polyolefin resin has a functional group, the functional group can react with and bond to other layers such as a resin substrate, thereby increasing adhesion, and further improving durability such as hydrolysis resistance, heat resistance, and flexibility.

[0017] In addition, the silica particles create an uneven surface near the interface of the highly adhesive coating layer. The uneven shape penetrates into the fine unevenness on the surface of other layers such as resin substrates, increasing the contact area and creating a hook-anchor effect, thereby improving the adhesion between the high-adhesion coating layer and other layers such as resin substrates. Furthermore, when the silica microparticles have functional groups, the functional groups can react with and bond to other layers such as resin substrates, polyolefin resins, other resins, etc., thereby increasing adhesion, and further improving durability such as hydrolysis resistance, heat resistance, and flexibility.

[0018] The highly adhesive coating composition of the present invention may be used as an adhesive, a primer, or a pretreatment agent for metal plating. By using the highly adhesive coating composition of the present invention as an adhesive or primer, functional layers and the like can be laminated with high adhesion, and the peel resistance of the laminate can be improved. Furthermore, even if the resin layer is made of a material that is difficult to metal plate, by using the high adhesion coating composition of the present invention as a pretreatment agent for metal plating to form a high adhesion coating layer, it becomes possible to easily form a metal plating layer on the resin substrate.

[0019] [Silica fine particles] The fine silica particles contained in the highly adhesive coating composition of the present invention preferably contain fumed silica and / or colloidal silica. Fumed silica is powdered amorphous silica, and preferably contains nanosilica. The average particle size of the nanosilica is preferably 2 to 500 nm, more preferably 5 to 50 nm, and even more preferably 8 to 20 nm. If the average particle size is smaller than the above range, secondary aggregation is likely to occur, and if it is larger than the above range, it is likely to be difficult to achieve a balance between surface hardness, sliding properties, and adhesion to the base layer.

[0020] Colloidal silica is a colloidal solid of silica particles dispersed in a solvent, and the mixture of colloidal silica and a solvent is called a colloidal silica sol. The colloidal silica is preferably nano-sized.

[0021] The colloidal silica contained in the highly adhesive coating composition of the present invention preferably contains chain silica and / or pearl necklace silica. Since chain silica and pearl necklace-shaped silica have a large uneven structure, when the silica microparticles are chain silica and / or pearl necklace-shaped silica, the effect of increasing the surface hardness and adhesion of the high-adhesion coating layer is enhanced.

[0022] The content of chain silica and / or pearl necklace-shaped silica in the total silica fine particles is preferably 60% by mass or more and 100% by mass or less, more preferably 70% by mass or more and 95% by mass or less. If it is less than the above range, the effect of increasing the surface hardness and adhesion of the high-adhesion coating layer is likely to be insufficient, and if it is more than the above range, the effect of increasing the surface hardness and adhesion of the high-adhesion coating layer is not significantly improved.

[0023] [Polyolefin resin] The polyolefin resin contained in the high-adhesion coating composition of the present invention is preferably a chlorinated and / or maleic anhydride-modified polyolefin, which improves the balance of solubility, compatibility, affinity, and adhesion at the adhesion interface in the system. The polyolefin resin may be chlorinated or may not be chlorinated. The polyolefin resin may be modified with maleic anhydride or may not be modified with maleic anhydride.

[0024] The softening point of the polyolefin resin is preferably 50 to 100° C., more preferably 65 to 90° C. If the softening point is lower than the above range, adhesion tends to be insufficient, and if it is higher than the above range, compatibility, affinity, and adhesion tend to decrease. The polyolefin resin preferably has a polypropylene structural portion made of a (co)polymer of a propylene monomer. Furthermore, the polyolefin resin may be a copolymer having a soft segment.

[0025] The higher the chlorine content of the chlorinated polyolefin resin, the more improved its solubility, compatibility and affinity in the system, but the more likely it is that its adhesion will decrease. When chlorinated, the chlorine content is preferably 15 to 30 mass %, more preferably 15 to 25 mass %.

[0026] The higher the maleic anhydride modification rate of the maleic anhydride-modified polyolefin, the more improved the reactivity, solubility in the system, compatibility and affinity, but the stability of the high-adhesion coating composition tends to decrease. When modified with maleic anhydride, the content of the maleic anhydride-derived moiety is preferably 5 to 30% by mass. Specific examples of polyolefin resins include chlorinated polyolefin, maleic anhydride-modified polyolefin resin, and chlorinated maleic anhydride-modified polyolefin resin.

[0027] [solvent] The solvent contained in the highly adhesive coating composition of the present invention is not particularly limited as long as it can dissolve or sufficiently uniformly disperse the silica microparticles and polyolefin-based resin, but it is preferable that the composition contains an alcohol-based solvent and / or a glycol-based solvent. When the highly adhesive coating composition of the present invention is cured at low temperature, it is preferable to use a solvent having a low boiling point in order to dry it at low temperature.

[0028] When the highly adhesive coating composition of the present invention is to be dried and cured at 40° C. or less within 1 hour, for example, it is preferable to use a solvent having 10 or less carbon atoms and a boiling point of 50 to 90° C. Solvents with a boiling point lower than the above range are difficult to handle, while solvents with a higher carbon number and a higher boiling point than the above range require high temperatures and long times to dry the highly adhesive coating layer formed from the highly adhesive coating composition.

[0029] When the highly adhesive coating composition of the present invention is dried at, for example, 80°C or higher, the appearance can be made smoother by using a high-boiling point solvent having a boiling point of 120 to 220°C in combination.

[0030] Specific examples of alcohol-based solvents include methanol (carbon number 1, boiling point 65°C), ethanol (carbon number 2, boiling point 78°C), normal propanol (carbon number 3, boiling point 97°C), isopropyl alcohol (carbon number 3, boiling point 82°C), tertiary butanol (carbon number 4, boiling point 82°C), normal butanol (carbon number 4, boiling point 118°C), isobutanol (carbon number 4, boiling point 108°C), and secondary butanol (carbon number 4). Examples of alcohols include, but are not limited to, ethanol and normal butanol.

[0031] Specific examples of glycol-based solvents include alkylene glycols and alkylene glycol ethers. Specific examples of alkylene glycols include, but are not limited to, ethylene glycol (carbon number 2, boiling point 197°C), propylene glycol (carbon number 3, boiling point 189°C), butylene glycol (carbon number 4, boiling point 207°C), hexylene glycol (carbon number 6, boiling point 197°C), and octylene glycol (carbon number 8, boiling point 175°C).

[0032] Specific examples of alkylene glycol ethers include, but are not limited to, ethylene glycol monomethyl ether (carbon number 3, boiling point 124°C), ethylene glycol monoethyl ether (carbon number 4, boiling point 135°C), ethylene glycol diethyl ether (carbon number 6, boiling point 121°C), ethylene glycol monoisopropyl ether (carbon number 5, boiling point 141°C), ethylene glycol monobutyl ether (carbon number 6, boiling point 171°C), propylene glycol monomethyl ether (carbon number 4, boiling point 120°C), propylene glycol monoethyl ether (carbon number 5, boiling point 132°C), propylene glycol mono-normal propyl ether (carbon number 6, boiling point 149°C), and propylene glycol mono-normal butyl ether (carbon number 7, boiling point 171°C). Among these, propylene glycol monomethyl ether is preferred. The highly adhesive coating composition of the present invention may contain one of the above solvents alone or two or more of them in combination.

[0033] [Adhesion promoter] Examples of adhesion promoters that can be contained in the high-adhesion coating composition of the present invention include alkoxysilanes, silane coupling agents, titanium coupling agents, silane / titanium condensates, high-adhesion resins, etc., and the high-adhesion coating composition of the present invention can contain one or more types selected from the group consisting of these. The content of the adhesion promoter is preferably 0.1% by mass or more and 50% by mass or less of the total solid content of the highly adhesive coating composition. If the amount is less than the above range, the effect of containing the adhesion promoter is not easily exhibited, whereas if the amount is greater than the above range, poor curing is likely to occur.

[0034] (alkoxysilane) Specific examples of alkoxysilanes include, but are not limited to, tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetrabutoxysilane, methyltrimethoxysilane, ethyltriethoxysilane, propyltripropoxysilane, and butyltributoxysilane. In the present invention, the above compounds can be used alone or in combination of two or more as the alkoxysilane.

[0035] (Silane coupling agent) Examples of the silane coupling agent include amino group-containing alkoxysilanes and epoxy group-containing alkoxysilanes.

[0036] Specific examples of amino group-containing alkoxysilanes include, but are not limited to, 3-aminopropyltrimethoxysilane, 3-aminopropylmethyldimethoxysilane, 3-aminopropyldimethylmethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropylethyldiethoxysilane, 3-aminopropyldiethylethoxysilane, 8-aminooctyltrimethoxysilane, etc. Among these, 3-aminopropyltrimethoxysilane is preferred. In the present invention, the above compounds can be used alone or in combination of two or more as the amino group-containing alkoxysilane.

[0037] Specific examples of epoxy group-containing alkoxysilanes include, but are not limited to, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyldimethylmethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylethyldiethoxysilane, 3-glycidoxypropyldiethylethoxysilane, and 8-glycidoxyoctyltrimethoxysilane. Among these, 3-glycidoxypropyltrimethoxysilane and 3-glycidoxypropylmethyldimethoxysilane are preferred. In the present invention, the above compounds can be used alone or in combination of two or more as the epoxy group-containing alkoxysilane.

[0038] (Titanium coupling agent) The titanium coupling agent is a compound in which the Si atom of the above silane coupling agent is substituted with a Ti atom.

[0039] (Silane / titanium condensate) The silane / titanium condensate is a hydrolysis condensation product of one or more members selected from the group consisting of alkoxysilanes, silane coupling agents, and titanium coupling agents in the presence of an acid catalyst. Specific examples of acid catalysts include, but are not limited to, hydrochloric acid, sulfuric acid, nitric acid, p-toluenesulfonic acid, benzenesulfonic acid, 10-camphorsulfonic acid, formic acid, oxalic acid, acetic acid, monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, and lactic acid.

[0040] (High adhesion resin) As the highly adhesive resin, a resin or oligomer having an alkoxysilyl group or a phenyl group is preferred. The alkoxysilyl group can react with other layers such as silica fine particles and resin substrates to form crosslinks. Urethane resins, resins having a phenyl group, and (meth)acrylic resins can enhance the affinity and adhesion to resin substrates.

[0041] Specific examples of highly adhesive resins include acrylic resins having an alkoxysilyl group, urethane resins having an alkoxysilyl group, and phenyl-substituted alkylsilicate partial hydrolysis condensation oligomers having an alkoxysilyl group. In order to obtain high adhesion, for example, the weight average molecular weight of the acrylic resin having an alkoxysilyl group determined by gel permeation chromatography (GPC) is preferably 1,500 to 100,000.

[0042] [Curing accelerating catalyst] The curing-accelerating catalyst can accelerate the hydrolysis reaction and dehydration condensation reaction at the interface with other layers such as silica fine particles, polyolefin resin, and resin substrate layer.

[0043] The content of the curing-accelerating catalyst in the high-adhesion coating composition of the present invention is preferably 0.05 to 10 mass %, more preferably 0.1 to 5.0 mass %. If the content is less than this range, the promoting effect of increasing the surface hardness of the high-adhesion coating layer is likely to be insufficient, and if it is more than this range, the surface hardness of the high-adhesion coating layer is likely to be non-uniform.

[0044] The curing-accelerating catalyst may be an acid catalyst or a base catalyst. Specific examples of the acid catalyst include hydrochloric acid, sulfuric acid, nitric acid, p-toluenesulfonic acid, and benzenesulfonic acid. Examples of suitable acetic acids include, but are not limited to, acetic acid, 10-camphorsulfonic acid, formic acid, oxalic acid, acetic acid, monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, lactic acid, and the like. Specific examples of the base catalyst include triethyleneamine, dimethylaminoethanol, and aqueous ammonia. Among these, the acid catalyst, nitric acid, is preferred. In the present invention, the above compounds can be used alone or in combination of two or more as the curing-accelerating catalyst.

[0045] <Method for producing highly adhesive coating composition> The highly adhesive coating composition of the present invention can be produced, for example, by the following method. 1) The acid catalyst is added dropwise to the solvent and mixed with stirring to prepare a catalyst solution. 2) The silica fine particles, polyolefin resin, and solvent are mixed by stirring. 3) While dropping the catalyst solution prepared above, the mixture is stirred and mixed at 10 to 60°C for about 1 hour. 4) If necessary, an adhesion promoter, a surface conditioner, etc. are added and mixed by stirring. 5) A solvent is added appropriately to obtain a concentration and viscosity that are appropriate for the desired coating method and conditions, thereby obtaining a highly adhesive coating composition. 6) The resulting highly adhesive coating composition may be filtered, for example, through a filter with mesh sizes of 0.5 to 2 μm.

[0046] <Coating method of high-adhesion coating composition> There are no particular limitations on the method for coating the highly adhesive coating composition of the present invention onto a resin substrate, and for example, a coating method including one selected from the group consisting of dip coating, spin coating, and spray coating can be used. The drying and curing temperature of the coated highly adhesive coating composition of the present invention is preferably 15 to 150°C.

[0047] When laminating a functional layer on a high-adhesion coating layer made of the high-adhesion coating composition of the present invention, the high-adhesion coating layer may be in an uncured, semi-cured, or cured state, and there is no need to laminate the functional layer in an uncured or semi-cured state like an adhesive layer. The highly adhesive coating composition of the present invention cures at room temperature, but may also be baked at a high temperature. Specifically, drying and curing are preferably carried out for 1 to 75 minutes, more preferably 1 to 60 minutes, at 15 to 160° C., and even more preferably 45 to 60 minutes at 25 to 50° C. However, depending on the composition of the high-adhesion coating composition and the composition of the resin substrate layer, drying and curing can also be carried out at a higher temperature and for a longer time than the above. In the case of room temperature curing type, drying and curing at room temperature for 1 minute, 10 minutes, 1 hour, etc. is possible at 15 to 40° C. However, it is preferable to contain a solvent that dries sufficiently at room temperature. Standard conditions are 1 to 10 minutes at 80°C. When baking is performed at a high temperature, the hardness of the highly adhesive coating layer increases, but if the softening point of the resin substrate is below 80°C, there is a risk of deformation of the resin substrate.

[0048] <High adhesion laminate> The high-adhesion laminate of the present invention is a laminate including at least a substrate layer made of a resin substrate and a high-adhesion coating layer made of the high-adhesion coating composition of the present invention, and the high-adhesion coating layer is laminated adjacent to the resin substrate. The high-adhesion laminate may further include a functional layer laminated on the high-adhesion coating layer. The functional layer is, for example, a hydrophilic layer, a water-repellent layer, an antibacterial layer, a hard coat layer, an anti-reflection layer, etc., and may include one or more types selected from the group consisting of these. The highly adhesive laminate of the present invention has excellent interlayer adhesion, hydrolysis resistance, heat resistance, flexibility, and other durability properties.

[0049] [Base material layer] The substrate layer is an object to be coated with the highly adhesive coating composition of the present invention. The substrate layer is a layer made of a resin substrate, and the surface of the substrate layer may be surface-treated or may be laminated with a paint layer such as a primer layer or an acrylic clear coating film. Examples of resin materials for the resin substrate include, but are not limited to, PMMA (polymethyl methacrylate), PC (polycarbonate), PET (polyethylene terephthalate), PP (polypropylene) resins, etc. Among these, PMMA is preferred. The thickness of the substrate layer is not particularly limited, but is preferably 0.1 to 5.0 mm. The surface treatment of the base layer may be, for example, antiglare treatment (AG treatment), and the antiglare treatment preferably results in a surface roughness Ra of 0.5 to 20 nm.

[0050] [Highly adhesive coating layer] The highly adhesive coating layer is a layer formed from the highly adhesive coating composition of the present invention. The thickness of the highly adhesive coating layer is preferably 50 to 2000 nm, more preferably 100 to 1000 nm. If the thickness is thinner than the above range, adhesion tends to be poor, and it is practically difficult to achieve a thickness greater than the above range because the coating method is limited.

[0051] [Hydrophilic layer] The hydrophilic layer is a layer formed from a hydrophilic layer composition. The hydrophilic layer is not particularly limited, but is preferably made of silicate particles having silanol groups on their surfaces, colloidal silica having silanol groups on their surfaces and having irregularities, a compound having a carboxyl group, a compound having a sulfone group, a hydrophilic water-soluble resin such as polyacrylamide or polyethylene glycol.

[0052] [Water-repellent layer] The water-repellent layer is a layer formed from a water-repellent layer composition. The water-repellent layer is not particularly limited, but is preferably made of silicone silicate having an alkyl group with 1 to 5 carbon atoms at the terminal, a fluorine-based silane coupling agent, or the like.

[0053] [Antibacterial layer] The antibacterial layer is a layer formed from an antibacterial layer composition. The antibacterial layer is not particularly limited, but is preferably made of a quaternary ammonium salt, a photocatalyst, or the like.

[0054] [Hard coat layer] The hard coat layer is a layer formed from a hard coat layer composition. The hard coat layer is not particularly limited, but is preferably made of silicate or the like.

[0055] [Anti-reflection layer] The antireflective layer is a layer formed from an antireflective layer composition. The antireflection layer is not particularly limited, but is preferably made of hollow silica, chain silica, or the like, and has a low refractive index. [Example]

[0056] The present invention will be described in detail below with reference to examples. Therefore, it is not limited to this.

[0057] <Raw materials> The raw materials used in the examples are listed below.

[0058] [silica] Silica microparticle solution 1: Snowtex ST-PS-M manufactured by Nissan Chemical Co., Ltd. Pearl necklace-shaped nano-sized silica Na + Stable alkaline sol. Particle size 25 nm, solid content 20% by mass. Solvent is water. Silica particle solution 2: Snowtex STO-UP manufactured by Nissan Chemical Co., Ltd. Na chain nano-sized silica + Stable alkaline sol. Particle size 12 nm, solid content 15% by mass. Solvent is water. Silica particle solution 3: Snowtex ST-30 manufactured by Nissan Chemical Co., Ltd. Na nano-sized silica + Stable alkaline sol. Particle size 12 nm, solid content 30% by mass. Solvent is water.

[0059] [Polyolefin resin] Polyolefin resin solution 1: Hardlen EH-801J manufactured by Toyobo MC Co., Ltd. An aqueous solution containing 30% resin by mass. The chlorine content of the resin component is 16% by mass, and the softening point is 87°C. Polyolefin resin solution 2: Hardlen NZ-1004 manufactured by Toyobo MC Co., Ltd. Aqueous solution with a resin concentration of 30% by mass. Maleic anhydride modified product. The chlorine content of the resin component is 0% by mass, and the softening point is 70°C. Polyolefin resin solution 3: Hardlen NZ-1015 manufactured by Toyobo MC Co., Ltd. Aqueous solution with a resin concentration of 30% by mass. The chlorine content of the resin component is 0% by mass, and the softening point is 80°C. Polyolefin resin solution 4: Hardlen HM-21P manufactured by Toyobo MC Co., Ltd. Resin content: 100% by mass. The chlorine content of the resin component is 21% by mass, and the softening point is 87°C.

[0060] [Adhesion promoter] ·Silicate Oligomer 1: Silicate 40 manufactured by Tama Chemicals Co., Ltd. A mixture of polyethyl silicate, tetraethoxysilane, and a solvent. Non-volatile content: 100% by mass. 60-70% by mass of the non-volatile content is polyethyl silicate.

[0061] [Silane coupling agents] KBM-9418-40: Silane coupling agent containing a quaternary ammonium salt (CH3O)3Si-CH2CH2CH2N, manufactured by Shin-Etsu Chemical Co., Ltd. + (CH3)2(C 18 H 37 )Cl - Contains 40% by weight of active ingredient in methanol solution.

[0062] [Base material] Resin substrate 1: Polypropylene resin plate. PPN-050501. Thickness: 1mm. [Commercially available coating agents] ·Commercially available 1: GP Clear manufactured by Konishi Co., Ltd.

[0063] [Preparation of Nitric Acid Solution 1] The following was mixed to obtain a nitric acid solution 1 as a catalyst. 10% nitric acid aqueous solution 1.0 parts by mass Water 3.0 parts by mass Ethanol 30 parts by mass

[0064] [Preparation of silicate binder 1] First, the following were mixed to obtain a mixed solution. Silicate oligomer 1 8.0 parts by mass Ethanol 30 parts by mass Then, 34 parts by mass of the nitric acid solution 1 obtained above was added dropwise while stirring and mixing at 40° C. for 1 hour. Next, the following was further added and mixed with stirring to obtain silicate binder 1 (solid content 4% by mass). Ethanol 28.0 parts by mass

[0065] [Preparation of Functional Layer Composition] (Preparation of Hydrophilic Layer Composition 1) Hydrophilic layer composition 1 was prepared by mixing the following: Silicate binder 1 3.8 parts by mass Silica fine particle solution 2 11.3 parts by mass Water 84.9 parts by mass

[0066] (Preparation of Water-Repellent Layer Composition 1) Water-repellent layer composition 1 was prepared by mixing the following: Silicate binder 1 7.2 parts by mass Perfluorohexylethyltriethoxysilane 0.8 parts by mass Water 92.0 parts by mass

[0067] (Preparation of Antibacterial Layer Composition 1) Antibacterial layer composition 1 was prepared by mixing the following: KBM-9418-40 2.5 parts by mass Ethanol 97.5 parts by mass

[0068] (Preparation of Hard Coat Layer Composition 1) The silicate binder 1 (solid content: 4% by mass) prepared above was used as a hard coat layer composition 1 as it was.

[0069] (Preparation of Antireflection Layer Composition 1) Antireflection layer composition 1 was prepared by mixing the following: Silicate binder 1 3.8 parts by mass Silica fine particle solution 2 11.3 parts by mass Ethanol 84.9 parts by mass

[0070] [Example 1] The following raw materials were mixed to prepare a highly adhesive coating composition. Silica fine particle solution 1 40 parts by mass Polyolefin resin solution 1 6.7 parts by mass Water 53.3 parts by mass The obtained high-adhesion coating composition was applied to a resin substrate 1 by spin coating, dried, and baked by heating at 120°C for 30 minutes to form a high-adhesion coating layer, thereby obtaining a laminate. Then, various evaluations were carried out.

[0071] [Examples 2 to 12, Comparative Examples 1 and 2] Highly adhesive coating compositions were prepared in the same manner as in Example 1, except that the raw materials were changed according to the descriptions in Tables 1, 2, and 4, and laminates were obtained and evaluated.

[0072] [Examples 13 to 17] A highly adhesive coating composition was prepared in the same manner as in Example 1, except that the raw materials were changed according to the description in Table 2, and then heated at 120°C for 30 minutes to form a highly adhesive coating layer. Furthermore, according to the description in Table 3, hydrophilic layer composition 1, water-repellent layer composition 1, antibacterial layer composition 1, hard coat layer composition 1, or antireflection layer composition 1 was applied by spin coating onto the high adhesion coating layer, dried, and baked by heating at 120°C for 30 minutes to form a hydrophilic layer, water-repellent layer, antibacterial layer, hard coat layer, or antireflection layer, and a laminate was obtained and evaluated.

[0073] [Examples 18 to 19] The same procedure as in Example 1 was carried out except that the highly adhesive coating composition was applied by the coating method described in Table 4, and a highly adhesive coating composition was prepared, a laminate was obtained, and the laminate was evaluated. In the application by the dip coating method, the resin substrate 1 was immersed in the highly adhesive coating composition, hung upright, and left to dry for 1 minute. The spray coating was carried out under the following conditions. Atomization pressure: 400kPa Discharge amount: 0.5~20ml / min Spray distance: 10~200mm Head speed: 500mm / sec Pitch: 7mm

[0074] Comparative Example 3 A highly adhesive coating composition was prepared in the same manner as in Example 1, except that Commercially Available 1 was used as the highly adhesive coating composition according to the description in Table 4, and a laminate was obtained and evaluated.

[0075] <Evaluation method> First, the highly adhesive coating composition was applied onto a degreased resin substrate 1, and then dried and cured at 80° C. for 30 minutes to form a highly adhesive coating layer. Furthermore, if necessary, a functional layer was formed on the highly adhesive coating layer. The resulting high-adhesion laminate was then subjected to the following evaluations.

[0076] [Adhesion to resin substrates] Cellophane tape was applied to the (functional layer and) high-adhesion coating layer and then peeled off, and the degree of peeling between the high-adhesion coating layer and the resin substrate and the appearance of the high-adhesion coating layer were evaluated by visual inspection. The symbols in the table have the following meanings: ◎: The cellophane tape is cut and remains in its entirety, and the appearance of the highly adhesive coating layer remains unchanged. 〇: Some of the cellophane tape remains, and the appearance of the highly adhesive coating layer remains unchanged. 〇△: The cellophane tape peeled off, and the appearance of the highly adhesive coating layer remained unchanged. △: Cohesive failure occurred in the highly adhesive coating layer ×: Full peeling at the highly adhesive coating layer / substrate interface

[0077] [Contact angle (hydrophilicity, water repellency)] In accordance with JIS K6768 (Plastics - Films and sheets - Wet tension test method), a water droplet was dropped onto the (functional layer and) high adhesion coating layer on the resin substrate 1, and the contact angle of the water droplet on the surface of the high adhesion coating layer was measured. Contact angle of 20 degrees or less: Highly hydrophilic Contact angle of 85 degrees or less: Highly water-repellent

[0078] [Antibacterial] The antibacterial properties of the (functional layer and) highly adhesive coating layer on the resin substrate 1 were evaluated in accordance with JIS Z 2801 (antibacterial properties, non-textile products). The symbols in the table have the following meanings: 〇: Antibacterial activity value 2 or more ×: Antibacterial activity value less than 2

[0079] [Surface hardness] The surface hardness of the (functional layer and) high-adhesion coating layer on the resin substrate 1 was measured in accordance with JIS K5600 "4.4 Scratch hardness (pencil method) of general test methods for paints."

[0080] [Minimum reflectance] The surface of the high-adhesion laminate on the resin substrate 1 side was painted black, and black tape was attached to prevent light from passing through the high-adhesion laminate. The reflectance of the surface on the (functional layer and) high-adhesion coating layer side was measured using an ultraviolet-visible spectrophotometer (UV-2600, manufactured by Shimadzu Corporation).

[0081] [Rubbing resistance (dry)] The (functional layer and) high-adhesion coating layer on the resin substrate 1 was rubbed back and forth 20 times with a dry paper cloth (Kimwipe manufactured by Kimberly-Clark) at a load of 500 g, and the degree of peeling of the high-adhesion coating layer was visually confirmed. The symbols in the table have the following meanings: 〇: No peeling △: Partial peeling ×: Complete peeling

[0082] [Rubbing resistance (wet)] The (functional layer and) high-adhesion coating layer on the resin substrate 1 was rubbed back and forth 20 times with a water-soaked paper cloth (Kimwipe manufactured by Kimberly-Clark Corporation) under a load of 500 g, and the degree of peeling of the high-adhesion coating layer was visually confirmed. The symbols in the table have the following meanings: ◎: No peeling 〇: Slight peeling but no problem △: Partial peeling ×: Complete peeling

[0083] [exterior] First, the highly adhesive coating composition was applied onto a degreased glass substrate, and then dried and cured at 120°C for 30 minutes to form a highly adhesive coating layer. Furthermore, if necessary, a functional layer was formed on the highly adhesive coating layer. Then, black tape was attached to the rear surface of the glass substrate layer, and sunlight was applied to the surface, and the presence or absence and degree of abnormality in the highly adhesive coating layer formed on the glass substrate layer was visually observed. The symbols in the table have the following meanings: 〇: Uniform transparent appearance △: Some unevenness ×: Significant irregularities such as unevenness

[0084] [Table 1]

[0085] [Table 2]

[0086] [Table 3]

[0087] [Table 4]

[0088] <Summary of evaluation results> The high adhesion coating compositions of all the examples of the present invention exhibited excellent adhesion to resin substrates and an excellent balance of adhesion to resin substrates, functionality (hydrophilicity, water repellency, antibacterial properties, surface hardness, or antireflection), rubbing resistance (dry), rubbing resistance (wet), and appearance. However, Comparative Examples 1 to 3 exhibited poor adhesion to the resin substrate and poor rubbing resistance (wet). [Industrial Applicability]

[0089] The highly adhesive coating composition of the present invention is useful as a surface coating material, and is particularly It is important as a surface coating material for resin substrates, and exhibits excellent adhesion even to substrates made of polypropylene-based resins. The highly adhesive coating composition of the present invention is also useful as a base material for plating or functional coating. [Explanation of symbols]

[0090] 1 High adhesion laminate 2 Base material layer 3 Highly adhesive coating layer 4 Functional Layer

Claims

1. A highly adhesive coating composition for a resin substrate, comprising silica fine particles, a polyolefin resin, and a solvent, the polyolefin resin is a chlorinated and / or maleic anhydride-modified polyolefin and has a softening point of 50 to 100°C; The mass ratio of silica fine particles to polyolefin resin is 0.2 to 20. A highly adhesive coating composition.

2. 2. The highly adhesive coating composition according to claim 1, wherein the silica fine particles are chain-like silica or pearl necklace-like silica.

3. 2. The highly adhesive coating composition according to claim 1, further comprising an adhesion promoter and / or a curing-accelerating catalyst.

4. The highly adhesive coating composition further contains an adhesion promoter, 2. The highly adhesive coating composition according to claim 1, wherein the adhesion promoter is at least one selected from the group consisting of alkoxysilanes, silane coupling agents, titanium coupling agents, and silane / titanium condensates.

5. A coating method for coating a resin substrate with the highly adhesive coating composition according to any one of claims 1 to 4, comprising the steps of: The coating method includes one selected from the group consisting of a dip coating method, a spin coating method, and a spray coating method. A coating method comprising:

6. A high-adhesion laminate including a substrate layer and a high-adhesion coating layer, the substrate layer is a layer made of a resin substrate, The highly adhesive coating layer is a layer made of the highly adhesive coating composition according to any one of claims 1 to 4, and is laminated adjacent to the resin substrate. A highly adhesive laminate.

7. A high-adhesion laminate further having a functional layer on the high-adhesion coating layer, The functional layer is one or more layers selected from the group consisting of a hydrophilic layer, a water-repellent layer, an antibacterial layer, a hard coat layer, and an antireflection layer. The highly adhesive laminate according to claim 6 .

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