JP7226934B2 - Resin composition and laminate - Google Patents

Description

The present invention relates to resin compositions and laminates.

BACKGROUND ART Paints and paint substitute films are used for painting vehicles such as automobiles. In particular, paints and coating substitute films used for the exterior of vehicles need flexibility to follow the shape of the vehicle, and weather resistance is also required. In addition to weather resistance, resistance to oil such as gasoline and brake oil is required. Furthermore, films are generally required to have anti-blocking properties. Therefore, it is preferable that the surface of the paint or paint substitute film as described above is covered with a protective layer.

For example, Patent Document 1 below discloses a coating film obtained by curing a resin composition containing a fluorinated olefin polymer and an acrylic polymer with an adduct-type cross-linking agent derived from hexamethylene diisocyanate. Patent Document 2 below discloses a coating film made of a resin composition containing a fluororesin and a TMP adduct type cross-linking agent derived from xylene diisocyanate. These coatings are used as protective layers.

JP 2003-064295 A JP 2013-117023 A

A film used for the exterior of a vehicle or the like needs sufficient flexibility because it may be attached while being pulled. However, the coating film of Patent Document 1 does not have sufficient flexibility and weather resistance in such applications. Further, the coating film described in Patent Document 2 has good anti-blocking properties, but is insufficient in flexibility.

Accordingly, the present invention provides a resin composition capable of forming a protective layer having flexibility, weather resistance, fuel resistance, and blocking resistance, and a laminate having a resin layer comprising the resin composition. With the goal.

In order to solve the above problems, the resin composition of the present invention comprises a fluororesin and an isocyanate cross-linking agent, wherein the isocyanate cross-linking agent contains a bifunctional cross-linking agent derived from an aliphatic hydrocarbon isocyanate. .

Moreover, it is preferable that the isocyanate cross-linking agent further contains a cross-linking agent derived from an alicyclic isocyanate.

Moreover, it is preferable that the functional group ratio between the aliphatic hydrocarbon isocyanate-derived bifunctional cross-linking agent and the alicyclic isocyanate-derived cross-linking agent is 1:9 or more and 9:1 or less.

Further, the resin composition of the present invention further comprises a (meth)acrylic resin, and the content of the (meth)acrylic resin is the sum of the content of the fluororesin and the content of the (meth)acrylic resin). is 100 parts by mass, it is preferably 5 parts by mass or more and 25 parts by mass or less.

In this specification, (meth)acryl means one or both of acryl and methacryl. (Meth)acrylate means one or both of acrylate and methacrylate.

Moreover, the resin composition of the present invention preferably further contains an ultraviolet absorber and two or more hindered amine light stabilizers.

Moreover, in order to solve the above problems, the laminate of the present invention is characterized by comprising a base material and a resin layer composed of the above resin composition laminated on the base material.

INDUSTRIAL APPLICABILITY According to the present invention, a resin composition capable of forming a protective layer having flexibility, weather resistance, blocking resistance and fuel resistance, and a laminate having a resin layer comprising the resin composition are provided.

It is a figure which shows roughly the cross section of the laminated body which concerns on embodiment of this invention.

The embodiments illustrated below are intended to facilitate understanding of the present invention, and are not intended to limit and interpret the present invention. The present invention can be modified and improved from the following embodiments without departing from its gist.

[Laminate]
FIG. 1 is a diagram schematically showing a cross section of a laminate according to an embodiment of the invention. A laminate 1 of the present embodiment includes a substrate 3 and a resin layer 2 laminated on the substrate 3 .

The material of the base material 3 is not particularly limited. The base material 3 is made of resin, metal, ceramics, paper, wood, or a combination thereof, for example. Moreover, the thickness of the base material 3 is not particularly limited. The thickness of the base material 3 is, for example, 20 μm or more and 500 μm or less, preferably 30 μm or more and 100 μm or less.

Examples of resins that can be used as the base material 3 include polyvinyl chloride, polyvinylidene chloride, polyvinylidene fluoride, poly(ethylene-tetrafluoroethylene), polycarbonate, polyester, (meth)acrylic resin, polyolefin, polyamide, polyvinyl alcohol, polystyrene, polyurethane and the like. One of these resins may be used alone, or two or more thereof may be used in combination. When two or more kinds of resins are used in combination, these resins may be mixed to form a single substrate 3, or the substrate 3 may be formed of a plurality of layers made of different resins. Among the above resins, it is preferable to use polyvinyl chloride. The tensile elongation at break of polyvinyl chloride can be easily adjusted by adding a plasticizer or the like. Therefore, by using polyvinyl chloride for the substrate 3, the laminate 1 can follow the adherend surface even if the shape of the adherend surface to which the laminate 1 is adhered is complicated.

The resin layer 2 is a layer made of a resin composition which will be described later. Moreover, the thickness of the resin layer 2 is not particularly limited. The thickness of the resin layer 2 is, for example, 1 μm or more and 100 μm or less, preferably 3 μm or more and 20 μm or less.

The resin layer 2 is formed by applying a resin composition, which will be described later, onto the substrate 3 and curing the composition. Examples of coating methods for the resin composition include screen printing, gravure printing, bar coating, knife coating, roll coating, blade coating, die coating, spray coating, and dip coating. Among these, screen printing is particularly preferred. Means for curing the resin composition include, for example, a hot air dryer, an oven, a hot plate, and the like.

Alternatively, the resin composition of the present invention may be coated on a process film, dried with hot air, and peeled off to be used as a single-layer film.

The resin layer 2 may be transparent or colored. The laminate 1 including the resin layer 2 of the present embodiment is suitable, for example, as a film, a sticker, or the like to be attached to the interior or exterior parts of a vehicle or the surface of an object installed outdoors.

In addition, the laminated body 1 may also contain other members, such as an adhesive layer and an adhesive layer, for sticking to an adherend surface as needed. Moreover, between the resin layer 2 and the base material 3, a single-layer or multiple-layer printed layer, an adhesive layer, or the like may be provided. When the laminate 1 includes a printed layer between the resin layer 2 and the substrate 3, the method for forming the printed layer is not particularly limited. The printed layer is formed, for example, by applying a resin composition containing a resin, a coloring agent, a solvent, etc., onto the base material 3 by a method such as screen printing, and optionally undergoing processes such as drying and curing. . Further, when the laminate 1 includes a printed layer between the resin layer 2 and the base material 3, after forming the printed layer on the base material 3 as described above, the printed layer is subjected to the above-described process. A resin layer 2 is formed.

[Resin composition]
The resin composition forming the resin layer 2 of this embodiment contains a fluororesin, a (meth)acrylic resin, an isocyanate cross-linking agent, an ultraviolet absorber, and a hindered amine light stabilizer.

<Fluororesin>
The fluororesin contained in the resin composition of the present embodiment is a resin polymerized using a fluorine-containing compound monomer such as vinylidene fluoride, trifluoroethylene, tetrafluoroethylene, tetrafluoropropylene, and hexafluoropropylene. , other vinyl compounds may be included as copolymer components. Other vinyl compounds include, for example, ethylene, chlorotrifluoroethylene, vinyl ether, (meth)acrylic acid ester, (meth)acrylic acid, vinyl acetate, maleic acid, and maleic acid ester. The type of fluororesin is not particularly limited, and one type may be used alone, or two or more types may be used in combination. However, the fluororesin contained in the resin composition of the present embodiment is preferably a copolymer composed of trifluoroethylene and vinyl ether. A copolymer of trifluoroethylene and vinyl ether is an alternating copolymer, and therefore has particularly good weather resistance among fluororesins. Among fluororesins, copolymers of trifluoroethylene and vinyl ether have good compatibility with other resins and additives.

Moreover, the bond energy (441 kJ/mol) of the C—F bond in the fluororesin is greater than the maximum ultraviolet energy (411 kJ/mol) from sunlight. Therefore, the fluororesin is difficult to be decomposed by sunlight. Further, since the C—F bond has a small polarization, the fluororesin has poor reactivity and is difficult to be decomposed by hydrolysis or the like. Therefore, the heat resistance and weather resistance of the resin layer 2 can be improved by including the fluororesin in the resin composition that constitutes the resin layer 2 .

Moreover, from the viewpoint of improving the fuel resistance of the resin layer 2, it is preferable that the resin layer 2 is a coating film having a crosslinked structure. Therefore, the hydroxyl value of the fluororesin is preferably 30 mgKOH/g or more. By setting the hydroxyl value of the fluororesin to 30 mgKOH/g or more, the fluororesin can easily form a crosslinked structure, and the fuel resistance of the resin layer 2 can be improved. Moreover, from the viewpoint of suppressing deterioration of the flexibility of the resin layer 2, the hydroxyl value of the fluororesin is preferably less than 110 mgKOH/g, more preferably less than 60 mgKOH/g. When the hydroxyl value of the fluororesin is less than 100 mgKOH/g, the resin layer 2 can have sufficient flexibility even if the fluororesin is crosslinked.

Also, the glass transition temperature of the fluororesin is preferably 30° C. or higher and 90° C. or lower. By setting the glass transition temperature of the fluororesin to 30° C. or higher, the drying property of the resin composition can be improved, and the blocking resistance of the resin layer 2 can be improved.

<(Meth) acrylic resin>
The (meth)acrylic resin that the resin composition of the present embodiment may contain is a resin containing (meth)acrylic acid ester or (meth)acrylic acid as a monomer. Examples of such monomers include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 3-methyl-3- Hydroxybutyl (meth) acrylate, 1,3-dimethyl-3-hydroxybutyl (meth) acrylate, 2,2,4-trimethyl-3-hydroxypentyl (meth) acrylate, 2-ethyl-3-hydroxyhexyl (meth) Acrylate, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, poly (ethylene glycol-propylene glycol) mono (meth) acrylate, pentaerythritol tri (meth) acrylate, etc. (meth) acrylic monomers having a hydroxyl group body, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, i-propyl (meth) acrylate, n-butyl (meth) acrylate, i-butyl (meth) acrylate, t- Butyl (meth)acrylate, n-hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, octyl (meth)acrylate, cyclohexyl (meth)acrylate, phenyl (meth)acrylate, benzyl (meth)acrylate, phenoxyethyl (meth)acrylate ) acrylate, isobornyl (meth)acrylate, 2-methoxy (meth)acrylate, 2-ethoxy (meth)acrylate, glycidyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate and the like. One of these monomers may be used alone, or two or more thereof may be used in combination.

By containing a (meth)acrylic resin, the resin composition of the present embodiment can improve the adhesion between the resin layer 2 and the substrate 3 and the compatibility with additives contained in the resin composition. Due to the good compatibility between the resin and additives contained in the resin composition, for example, when the resin composition contains stabilizers such as ultraviolet absorbers (UVA) and light stabilizers (HALS), these Bleeding from the resin layer 2 over time can be suppressed. That is, the weather resistance of the resin layer 2 can be improved. In addition, since the resin composition contains a (meth)acrylic resin whose glass transition temperature can be easily adjusted, physical properties such as fuel resistance and blocking resistance of the resin layer 2 can be easily adjusted.

The (meth)acrylic resin preferably has a glass transition temperature of 30° C. or higher and 90° C. or lower. By setting the glass transition temperature of the (meth)acrylic resin to 30° C. or higher, the drying property of the resin composition can be improved, and the blocking resistance of the resin layer 2 can be improved.

Moreover, from the viewpoint of improving the fuel resistance of the resin layer 2, the hydroxyl value of the (meth)acrylic resin is preferably 30 mgKOH/g or more, more preferably 50 mgKOH/g or more. Moreover, from the viewpoint of suppressing deterioration of the flexibility of the resin layer 2, etc., the hydroxyl value of the (meth)acrylic resin is preferably less than 100 mgKOH/g, more preferably less than 80 mgKOH/g.

Further, the content of the (meth)acrylic resin in the resin composition constituting the resin layer 2 is 5 parts by mass when the total of the content of the fluororesin and the content of the (meth)acrylic resin is 100 parts by mass. It is preferable that it is more than 25 mass parts or less. If the content of the (meth)acrylic resin is 5 parts by mass or more, the compatibility of the additives contained in the resin composition is maintained, which is preferable. If the content of the (meth)acrylic resin is less than 25 parts by mass, the fluororesin provides weather resistance, which is preferable.

<Isocyanate cross-linking agent>
The isocyanate cross-linking agent contained in the resin composition of the present embodiment is preferably a non-yellowing isocyanate cross-linking agent. From the viewpoint of improving the flexibility of the resin layer 2, the isocyanate cross-linking agent is preferably an isocyanate cross-linking agent composed of an aliphatic hydrocarbon-based isocyanate. It is more preferable to have Therefore, the isocyanate cross-linking agent of the present embodiment contains at least a bifunctional cross-linking agent derived from an aliphatic hydrocarbon isocyanate.

Bifunctional cross-linking agents derived from aliphatic hydrocarbon isocyanates include, for example, isocyanate cross-linking agents derived from hexamethylene diisocyanate (HDI).

From the viewpoint of improving the fuel resistance and blocking resistance of the resin layer 2, the isocyanate cross-linking agent preferably further contains a cross-linking agent derived from an alicyclic isocyanate.

Examples of alicyclic isocyanate-derived cross-linking agents include, for example, hydrogenated xylylene diisocyanate (H ₆ XDI)-derived isocyanate cross-linking agents, hydrogenated diphenylmethane diisocyanate (H ₁₂ MDI)-derived isocyanate cross-linking agents, isophorone diisocyanate (IPDI)-derived isocyanate cross-linking agents and the like.

When the isocyanate cross-linking agent contains a bifunctional cross-linking agent derived from an aliphatic hydrocarbon isocyanate and a cross-linking agent derived from an alicyclic isocyanate, in order to achieve both flexibility and blocking resistance of the resin layer 2, the aliphatic hydrocarbon The functional group ratio of the bifunctional cross-linking agent derived from the polyisocyanate and the cross-linking agent derived from the alicyclic isocyanate is preferably 1:9 or more and 9:1 or less, and is preferably 3:7 or more and 7:3 or less. more preferred.

In addition, from the viewpoint of improving the fuel resistance of the resin layer 2, etc., the content of the isocyanate cross-linking agent is such that the isocyanate group contained in the isocyanate cross-linking agent is 0 relative to the hydroxyl value of the fluororesin and (meth)acrylic resin. An amount of 0.5 equivalent or more and 2.0 equivalent or less is preferable, an amount of 0.8 equivalent or more and 1.5 equivalent or less is more preferable, and an amount of 0.9 equivalent or more and less than 1.2 equivalent is even more preferable.

<Ultraviolet absorber>
The ultraviolet absorber contained in the resin composition of the present embodiment is preferably a triazine-based ultraviolet absorber. Triazine-based UV absorbers are less likely to yellow due to reaction with metal compounds or amines than benzotriazole-based UV absorbers. Therefore, the resin composition of the present embodiment can be prevented from yellowing due to contact with water. In addition, triazine-based ultraviolet absorbers tend to absorb ultraviolet rays in the wavelength band of 290 nm to 380 nm, which are involved in deterioration of organic compounds. Triazine-based UV absorbers can protect organic compounds from UV light, since they also absorb UV light beyond the 340 nm wavelength band.

The triazine-based ultraviolet absorber preferably contains a hydroxyphenyltriazine-based ultraviolet absorber. For example, triazine-based UV absorbers include 2-[4-{(2-hydroxy-3-alkyloxypropyl)oxy}-2-hydroxyphenyl]-4,6-bis(2,4-dimethylphenyl)-1 , 3,5-tridian. 2-[4-{(2-hydroxy-3-alkyloxypropyl)oxy}-2-hydroxyphenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-tridian is a hydroxyl group However, since the amount of phenolic hydroxyl groups is small, the cross-linking agent reacts with the hydroxyl groups, and bleeding can be suppressed.

In addition, the triazine-based ultraviolet absorber preferably contains a triazine-based ultraviolet absorber having an alkyl group having 12 or 13 carbon atoms, or a triazine-based ultraviolet absorber having an alkyl group having 12 carbon atoms and a carbon atom of the alkyl group. It is also preferred to include a mixture with number 13 triazine-based UV absorbers.

The content of the ultraviolet absorber contained in the resin composition forming the resin layer 2 is preferably 10 parts by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the resin contained in the resin composition.

<Hindered amine light stabilizer>
In this embodiment, it is preferable to use two or more hindered amine light stabilizers. Further, the hindered amine light stabilizer preferably contains an aminoether type hindered amine light stabilizer having an N—O—R structure and a hindered amine light stabilizer other than the aminoether type.

By including an amino ether type hindered amine light stabilizer having an NOR structure and a hindered amine light stabilizer other than the amino ether type in the resin composition constituting the resin layer 2, the resin and ultraviolet absorption It is believed that the radical sources involved in agent degradation can be rapidly quenched by these light stabilizers. Therefore, since the decomposition of the ultraviolet absorbent is suppressed, the ultraviolet absorption intensity of the ultraviolet absorbent is maintained.

The amino ether type hindered amine light stabilizer having an NOR structure preferably contains bis(1-octyloxy-2,2,6,6-tetramethyl-4-piperidinyl) sebacate. Bis(1-octyloxy-2,2,6,6-tetramethyl-4-piperidinyl)sebacic acid ester is relatively neutral among amino ether type hindered amine light stabilizers, so it inhibits cross-linking of resins. and yellowing can be suppressed.

The content of the amino ether type hindered amine light stabilizer having an N—O—R structure is 0.5 parts by mass or more and 6 parts by mass with respect to 100 parts by mass of the resin contained in the resin composition constituting the resin layer 2. The following are preferable. By setting the content of the amino ether hindered amine light stabilizer having an N—O—R structure to 0.5 parts by mass or more, deterioration of the resin layer 2 and the ultraviolet absorber can be suppressed. Further, by setting the content of the amino ether type hindered amine light stabilizer having an N—O—R structure to 6 parts by mass or less, the amino ether type hindered amine light stabilizer having an N—O—R structure bleed can be suppressed.

In addition, hindered amine light stabilizers other than the amino ether type include, for example, hindered amine light stabilizers composed of secondary amines and tertiary amines. Hindered amine light stabilizers other than aminoether types may include an ester compound consisting of 4-hydroxy-2,2,6,6-tetramethyl-1-piperidineethanol and 3,5,5-trimethylhexanoic acid. preferable. The ester compound is substantially neutral and hardly reacts with the proton-dissociating acidic group in the cross-linking agent or ultraviolet absorber. Therefore, cross-linking inhibition and yellowing of the resin can be suppressed.

The content of the hindered amine light stabilizer other than the amino ether type contained in the resin composition constituting the resin layer 2 is 3 parts by mass or more and 30 parts by mass or less with respect to 100 parts by mass of the resin contained in the resin composition. It is preferably 8 parts by mass or more and 30 parts by mass or less. By setting the content of the hindered amine light stabilizer other than the amino ether type to 3 parts by mass or more, the weather resistance of the resin layer 2 can be further improved. Further, by setting the content of the hindered amine light stabilizer other than the amino ether type to 30 parts by mass or less, the amino ether type hindered amine light stabilizer having the NOR structure and the hindered amine other than the amino ether type Bleeding of the system light stabilizer can be more suppressed.

The total content of the hindered amine light stabilizer is preferably 3.5 parts by mass or more and 36 parts by mass or less with respect to 100 parts by mass of the resin contained in the resin composition constituting the resin layer 2. More preferably, the amount is not less than 30 parts by mass and not more than 30 parts by mass. By setting the content of the hindered amine light stabilizer to 3.5 parts by mass or more, in addition to improving the weather resistance of the resin layer 2, it is possible to improve the substrate 3 and substrate protection. Further, by setting the content of the hindered amine light stabilizer to 36 parts by mass or less, bleeding of the hindered amine light stabilizer can be suppressed.

<Other ingredients>
The resin composition of this embodiment may contain other components as needed. Other components include catalysts, solvents, leveling agents, light stabilizers other than the above hindered amine light stabilizers, antioxidants, plasticizers, surfactants, colorants, brightening agents, fillers, and the like.

Tin compounds, for example, can be used as catalysts. For example, by adding a catalyst obtained by diluting a tin compound with acetylacetone or the like to the resin composition of the present embodiment, the cross-linking reaction by the cross-linking agent can be accelerated. Therefore, the blocking resistance of the resin layer 2 made of the resin composition of the present embodiment can be improved.

Examples of solvents include ketone-based solvents such as cyclohexanone, isophorone, diacetone alcohol, acetone, methyl ethyl ketone, methyl isobutyl ketone, and methylcyclohexanone, ethyl acetate, propyl acetate, butyl acetate, propylene glycol monomethyl ether acetate, butyl cellosolve acetate, and carbitol acetate. Ester solvents such as hexane, cyclohexane, octane, mineral spirits, kerosene and other aliphatic hydrocarbon solvents, toluene, xylene, 1,2,4-trimethylbenzene and other aromatic hydrocarbon solvents, and methylene chloride, Halogen-based solvents such as chloroform, carbon tetrachloride, dichloroethane, dichloroethylene, trichlorethylene, tetrachlorethylene, chlorobenzene, and dichlorobenzene can be used. One solvent may be used alone, or two or more solvents may be used in combination.

When using the resin composition of the present embodiment for screen printing, it is preferable to use a solvent having an evaporation rate ratio of 0.3 or less. Here, the evaporation rate ratio is the value of the relative evaporation rate of each solvent when the evaporation rate of butyl acetate is set to 1. There is a relationship that the smaller the evaporation rate ratio of the solvent, the slower the evaporation. When the resin composition contains a solvent having an evaporation rate ratio of 0.3 or less, drying of the plate during screen printing is suppressed, and workability tends to be improved.

Examples of leveling agents include fluorine-based leveling agents, silicon-based leveling agents, and acrylic leveling agents.

As described above, the resin composition of the present embodiment contains at least a fluororesin and a bifunctional cross-linking agent derived from an aliphatic hydrocarbon isocyanate, thereby improving weather resistance, flexibility, fuel resistance, and blocking resistance. It can be a protective layer having properties.

Although the present invention has been described using the above embodiment as an example, the present invention is not limited to the above embodiment. The resin composition of the present invention may contain at least a fluororesin and a bifunctional cross-linking agent derived from an aliphatic hydrocarbon isocyanate. agents and hindered amine light stabilizers are not essential components.

EXAMPLES Hereinafter, the content of the present invention will be described more specifically with reference to Examples and Comparative Examples, but the present invention is not limited to these.

(Example 1)
Fluororesin (trade name: Lumiflon (registered trademark) flake LF710F, manufactured by Asahi Glass Co., Ltd., copolymer composed of trifluoroethylene and vinyl ether, glass transition temperature: 51 ° C. or higher, hydroxyl value: 46 mg KOH / g) 90.0 mass part, acrylic resin (trade name: Nikalite (registered trademark) H4007, manufactured by Nippon Carbide Industry Co., Ltd., weight average molecular weight: about 8000, glass transition temperature: 51 ° C., hydroxyl value: 33.2 mgKOH / g) 10.0 parts by mass , A bifunctional cross-linking agent derived from an aliphatic hydrocarbon isocyanate (trade name: Duranate D-201, NCO content: 16%, manufactured by Asahi Kasei Corporation) 11.2 parts by mass, a cross-linking agent derived from an alicyclic isocyanate ( Trade name: Takenate D-120N, manufactured by Mitsui Chemicals, Inc., ethyl acetate solution of cross-linking agent containing trimethylolpropane (TMP) adduct derived from H ₆ XDI, solid content: 75 wt %, NCO content: 11%) 12 .3 parts by mass, triazine-based ultraviolet absorber (trade name: Tinuvin 400, manufactured by BASF Japan Co., Ltd.) 22.4 parts by mass, amino ether type hindered amine light stabilizer having an NOR structure {trade name: Tinuvin 123, manufactured by BASF Japan Ltd., bis (1-octyloxy-2,2,6,6-tetramethyl-4-piperidinyl) sebacate} 6.6 parts by mass, and hindered amines other than amino ether type Light stabilizer (trade name: Tinuvin 249, manufactured by BASF Japan Ltd., an ester compound consisting of 4-hydroxy-2,2,6,6-tetramethyl-1-piperidineethanol and 3,5,5-trimethylhexanoic acid ) were mixed to prepare a resin composition. The number of parts to be blended is based on the dry mass.

Table 1 shows the blending ratio of the resin composition in parts by mass based on the dry mass. Table 1 also shows the ratio "NCO/OH" of the OH groups derived from the fluororesin and acrylic resin contained in the resin composition and the NCO derived from the cross-linking agent. Furthermore, in Table 1, the ratio of NCO based on an aliphatic hydrocarbon isocyanate-derived bifunctional cross-linking agent (Duranate D-201) and NCO based on other cross-linking agents is shown in the functional group ratio "D-201/ Others”.

Next, an acrylic film (trade name: Hi-S Cal A0800, manufactured by Nippon Carbide Industry Co., Ltd., tensile elongation at break: 150%) was prepared as a substrate. An ink obtained by mixing 100 parts by mass of screen ink Hi-S SP-501MK (manufactured by Nippon Carbide Industry Co., Ltd.) and 50 parts by mass of BS thinner (manufactured by Nippon Carbide Industry Co., Ltd.) on this base material using a 225 mesh screen. was printed to form a printed layer. Next, the base material with the printed layer formed thereon was dried by heating in a hot air dryer at 60° C. for 60 minutes, and allowed to stand at 25° C. for 24 hours. After that, on the printed layer, 75 parts by mass of screen ink Hi-S SP-8500 (manufactured by Nippon Carbide Industry Co., Ltd.) and Hi-S SP-M-0 (manufactured by Nippon Carbide Industry Co., Ltd.) were applied using a 225 mesh screen. ) and 12.5 parts by mass of Hi-S SP-M-4-2 (manufactured by Nippon Carbide Industry Co., Ltd.). Next, the base material with the printed layer formed thereon was dried by heating in a hot air dryer at 60° C. for 60 minutes, and allowed to stand at 25° C. for 24 hours. Using a 180-mesh screen, the resin composition was printed so as to have a thickness of 20 μm after drying. After that, using a hot air dryer, heat drying was performed in an environment of 80° C. for 60 minutes, and left to stand in an environment of 25° C. for 5 hours to form a resin layer made of the resin composition on the printed layer. Thus, a laminate having a substrate layer, a printed layer and a resin layer was obtained.

(Examples 2 to 8 and Comparative Examples 1 to 6)
A laminate was obtained in the same manner as in Example 1, except that the formulation of the resin composition was changed as shown in Tables 1 to 3. Tables 2 and 3, like Table 1, show the compounding ratio of the resin composition. The fluororesin, acrylic resin, and cross-linking agent not used in Example 1 shown in Tables 1 to 3 are as follows.
Lumiflon (registered trademark) LF-552 is a trade name of a fluororesin manufactured by Asahi Glass Co., Ltd. The solid content is 40 wt %, the glass transition temperature is 30° C., and the hydroxyl value is 21 mgKOH/g.
Lumiflon (registered trademark) LF916F is a trade name of fluororesin powder manufactured by Asahi Glass Co., Ltd., and is a copolymer composed of trifluoroethylene and vinyl ether. The hydroxyl value is 100 mgKOH/g.
H4007K4 is a trade name of an acrylic resin manufactured by Nippon Carbide Industry Co., Ltd. It has a weight average molecular weight of about 8000, a glass transition temperature of 71° C., and a hydroxyl value of 30.4 mgKOH/g.
Duranate E405-80T is a trade name of a TMP adduct type cross-linking agent derived from aliphatic hydrocarbon isocyanate manufactured by Asahi Glass Co., Ltd. The NCO content is 7%.
Coronate HK is a trade name of a cross-linking agent manufactured by Tosoh Corporation, and is a polyisocyanate containing an isocyanurate form of hexamethylene diisocyanate (HMDI). The NCO content is 21%.
Takenate D-127N is a trade name of an alicyclic isocyanate-derived cross-linking agent manufactured by Mitsui Chemicals, Inc., and is a cross-linking agent containing an isocyanurate form of H ₆ XDI. The NCO content is 14%.
Takenate D-140N is a trade name of a TMP adduct type cross-linking agent derived from alicyclic isocyanate manufactured by Mitsui Chemicals, Inc. The NCO content is 11%.

<Evaluation method>
The laminates according to the above examples and comparative examples were evaluated by the methods described below. Evaluation results are as shown in Tables 1 to 3.

(Blocking resistance)
Ten sheets of 50 mm square laminates were stacked in the thickness direction, and the blocking resistance of the laminate after 24 hours when a load was applied in the thickness direction was evaluated according to the following criteria.
A: No significant change in appearance after applying a load of 1.0 kg B: No significant change in appearance after applying a load of 0.5 kg C: Release paper on the surface after applying a load of 0.5 kg with marks of

(Flexibility)
After the laminate was allowed to stand at 23° C. and 50% RH for 168 hours, it was cut into a test piece having a length of 150 mm and a width of 10 mm. After that, in accordance with JIS-Z0237, using a universal testing machine (manufactured by Toyo Baldwin Co., Ltd., device name: Tensilon TM-100), under the conditions of a grip interval of 100 mm and a tensile speed of 300 mm / min, the elongation that the resin layer cracks. degree was measured. Five test pieces were measured for each, and the arithmetic mean value thereof was used as a representative value, and evaluation was made according to the following criteria.
A: Breaking elongation 150% or more B: Breaking elongation 120% or more C: Breaking elongation 100% or more D: Breaking elongation 10% or more E: Breaking elongation 10% or less

(Weather resistance of laminate)
Put the laminate in a metal weather tester (manufactured by Daipla Wintes) with a KF-1 filter (295 nm to 780 nm), and test the resin layer at 75 mW / cm ² under an environment with a black panel temperature of 63 ° C and 50% RH. Illuminated on the side. During the light irradiation, the laminate was showered with water for 120 seconds every two hours. After irradiating the laminate with light for 200 hours and after irradiating it for 300 hours, the laminate was taken out from the tester. Then, the color difference before and after being put into the tester was measured from the resin layer side with a colorimeter CM-3600d manufactured by Konica Minolta, and the color difference before and after being put into the tester was evaluated according to the following criteria.
A: ΔE is less than 1 B: ΔE is 1 or more and less than 3 C: ΔE is 3 or more and less than 5 D: ΔE is 5 or more and less than 10 E: ΔE is 10 or more

(Weather resistance of resin layer)
In the same manner as in the weather resistance evaluation of the laminate, the laminate was irradiated with light while water was applied from the resin layer side of the laminate using a metal weather tester, and the laminate was removed from the tester after 200 hours and 300 hours. Then, the gloss value before and after being put into the tester is measured from the resin layer side with a gloss meter UGV-5 manufactured by Suga Test Instruments Co., Ltd., and the difference in the gloss value at a viewing angle of 60 ° before and after being put into the tester. was evaluated according to the following criteria.
A: Less than 1 B: 1 or more and less than 3 C: 3 or more and less than 5 D: 5 or more and less than 10 E: 10 or more

(Fuel resistance)
The laminate was immersed in gasoline to check for changes in the appearance of the resin layer, and evaluated according to the following criteria.
It was immersed in gasoline for 1 minute, removed from the gasoline, wiped off the surface, left to stand for 30 minutes, and then immersed again in gasoline for 1 minute. This was repeated 5 times, and then a change in appearance was confirmed. Gasoline with an octane number of 89 or more was used.
A: No change in appearance.
B: Appearance changed.

As shown in Tables 1 to 3, the resin compositions according to Examples 1 to 16 contain a fluororesin and a bifunctional cross-linking agent derived from an aliphatic hydrocarbon isocyanate. The resin layer made of the resin composition has a good balance of blocking resistance and fuel resistance in addition to flexibility and weather resistance. On the other hand, the resin layers made of the resin compositions of Comparative Examples 1 to 5 are inferior to those of Examples in at least one of flexibility and weather resistance.

As described above, the laminate comprising the resin composition of the present invention and the resin layer comprising the resin composition can achieve both weather resistance and flexibility.

INDUSTRIAL APPLICABILITY As described above, according to the present invention, a resin composition capable of forming a protective layer having weather resistance and flexibility and a laminate having a resin layer comprising the resin composition are provided. It is expected to be used in fields such as decoration.

DESCRIPTION OF SYMBOLS 1... Laminate 2... Resin layer 3... Base material

Claims (6)

A fluororesin having a hydroxyl value of 21 mgKOH/g or more and 100 mgKOH or less , a (meth) acrylic resin having a hydroxyl value of 30 mgKOH/g or more and less than 100 mgKOH, and an isocyanate cross-linking agent,
A resin composition, wherein the isocyanate cross-linking agent comprises a bifunctional cross-linking agent derived from an aliphatic hydrocarbon isocyanate and a cross-linking agent derived from an alicyclic isocyanate. 2. The functional group ratio of the bifunctional cross-linking agent derived from the aliphatic hydrocarbon isocyanate and the cross-linking agent derived from the alicyclic isocyanate is 1:9 or more and 9:1 or less. of the resin composition. The content of the (meth)acrylic resin is 5 parts by mass or more and 25 parts by mass or less, where the total of the content of the fluororesin and the content of the (meth)acrylic resin is 100 parts by mass. The resin composition according to claim 1 or 2. 4. The resin composition according to any one of claims 1 to 3, further comprising an ultraviolet absorber and two or more hindered amine light stabilizers. The two or more types of hindered amine light stabilizers include an amino ether type hindered amine light stabilizer having an N—O—R structure and a hindered amine light stabilizer other than the amino ether type. Item 5. The resin composition according to item 4. A laminate comprising a base material and a resin layer composed of the resin composition according to any one of claims 1 to 5 laminated on the base material.

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