JPWO2020241647A1 - UV curable urethane acrylate resin and UV curable resin composition containing it - Google Patents

Abstract

Provided is an ultraviolet curable urethane (meth) acrylate resin capable of forming a cured coating film having excellent transparency, extensibility, water repellency, and chemical resistance. The ultraviolet curable urethane (meth) acrylate resin according to the present invention is obtained by reacting (A) a polyisocyanate compound, (B) a diol compound, (C) (meth) acrylate compound, and (D) a hydroxyl group-containing fluorine compound. ..

Description

The present invention relates to an ultraviolet curable urethane acrylate resin. The present invention also relates to an ultraviolet curable resin composition containing an ultraviolet curable urethane acrylate resin. Furthermore, the present invention also relates to a cured coating film formed from an ultraviolet curable resin composition, a coated substrate having a cured coating film, and a method for producing a coated substrate.

In the field of plastic decoration used for automobile interiors, exterior members, home appliance housings, etc., decorative films for imparting functionality when molding plastic resin in a mold are used. Thermoforming methods such as in-mold molding, in which they are bonded together, are widely used.

Since the decorative film used for this thermoforming is required to have extensibility to follow the three-dimensional shape of the plastic as an adherend, a resin composition to be applied to the film surface in order to impart functionality. Is also required to have extensibility. A thermosetting resin composition may be used as the stretchable resin composition, but an ultraviolet curable resin composition is preferably used from the viewpoint of productivity and blocking property at the time of film winding. For example, as an ultraviolet curable resin composition having high breaking elongation and excellent moldability, a urethane acrylate obtained by reacting a polyfunctional acrylate monomer with a polyhydric alcohol with an isocyanate monomer or an organic polyisocyanate. It has been proposed to use oligomers (see Patent Document 1).

Further, the decorative film is also required to have antifouling properties (water repellency) and the like from the viewpoint of chemical resistance and stain prevention.

Japanese Unexamined Patent Publication No. 2018-111793

In order to impart chemical resistance and water repellency (stain resistance) to the resin molded product, the present inventors not only add urethane acrylate resin to the paint (resin composition) of the decorative film, but also fluorine. Attempts were made to post-add an additive (antifouling agent) such as a compound. However, since the resin such as the urethane acrylate oligomer described in Patent Document 1 has a strong cohesive force, when an additive such as a fluorine compound is added afterwards, it stays in the cured coating film and is difficult to be oriented on the surface of the coating film. It was found that water repellency (antifouling property) is difficult to develop. Therefore, it is desired that the urethane acrylate resin itself exhibits water repellency (antifouling property) without adding an additive (antifouling agent) such as a fluorine compound to the resin composition. In addition, when the resin molded product is decorated, the urethane acrylate resin is located on the outermost surface, so that it is highly transparent so as not to interfere with the design of the print layer, pattern layer, etc. located below it. desired.

The present invention has been made in view of the above background technology and new technical problems, and an object thereof is ultraviolet curing capable of forming a cured coating film having excellent transparency, extensibility, water repellency, and chemical resistance. The present invention is to provide a type urethane (meth) acrylate resin.

As a result of diligent studies to solve the above problems, the present inventors have reacted (A) a polyisocyanate compound, (B) a diol compound, (C) (meth) acrylate compound, and (D) a hydroxyl group-containing fluorine compound. It was found that the above-mentioned problems can be solved by using the ultraviolet curable urethane (meth) acrylate resin thus obtained. The present invention has been completed based on such findings.

That is, according to the present invention, the following invention is provided.
[1] (A) Polyisocyanate compound,
(B) Glycol compound,
(C) (meth) acrylate compound, and (D) hydroxyl group-containing fluorine compound,
UV curable urethane (meth) acrylate resin obtained by reacting with.
[2] The ultraviolet curable urethane (meth) acrylate resin according to [1], which contains an alicyclic polyisocyanate as a component (A).
[3] The ultraviolet curable urethane (meth) acrylate resin according to [1] or [2], which contains a chain aliphatic diol having 2 to 6 carbon atoms as a component (B).
[4] The ultraviolet curable urethane (meth) acrylate resin according to any one of [1] to [3], which contains pentaerythritol triacrylate as the component (C).
[5] The ultraviolet curable urethane (meth) acrylate resin according to any one of [1] to [4], wherein the equivalent ratio of the component (B) to the component (A) is 0.50 to 0.80.
[6] The ultraviolet curable urethane (meth) acrylate resin according to any one of [1] to [5], wherein the equivalent ratio of the component (C) to the component (A) is 0.20 to 0.50.
[7] The description according to any one of [1] to [6], wherein the amount of the component (D) is 0.01 to 10.0% by mass with respect to the total amount of the components (A), (B) and (C). UV curable urethane (meth) acrylate resin.
[8] An ultraviolet curable resin composition containing the ultraviolet curable urethane (meth) acrylate resin according to any one of [1] to [7] and a photopolymerization initiator.
[9] The ultraviolet curable resin composition according to [8], which is used as a paint.
[10] The ultraviolet curable resin composition according to [9], wherein the paint is used for a decorative film for in-mold molding.
[11] A cured coating film formed from the ultraviolet curable resin composition according to any one of [8] to [10].
[12] A substrate with a coating film, which comprises the cured coating film according to [11] on the substrate.
[13] A coating step of applying the ultraviolet curable resin composition according to any one of [8] to [10] to at least one surface of the substrate, and a coating step.
After the coating step, a curing step of curing the ultraviolet curable resin composition by ultraviolet irradiation to form a cured coating film, and a curing step.
A method for producing a base material with a coating film.

According to the present invention, it is possible to provide an ultraviolet curable urethane (meth) acrylate resin capable of forming a cured coating film having excellent transparency, extensibility, water repellency, and chemical resistance. Further, according to the present invention, it is also possible to provide a resin composition containing such an ultraviolet curable urethane (meth) acrylate resin. Further, it is also possible to provide a cured coating film formed from such an ultraviolet curable resin composition, a coated substrate provided with the cured coating film, and a method for producing the coated substrate.

It is a schematic sectional drawing which showed the base material with a coating film by this invention.

<UV curable urethane (meth) acrylate resin>
The ultraviolet curable urethane (meth) acrylate resin according to the present invention is obtained by reacting (A) a polyisocyanate compound, (B) a diol compound, (C) (meth) acrylate compound, and (D) a hydroxyl group-containing fluorine compound. It is a thing. Such an ultraviolet curable urethane (meth) acrylate resin can form a cured coating film having excellent transparency, extensibility, water repellency, and chemical resistance. Therefore, the ultraviolet curable resin composition containing the ultraviolet curable urethane (meth) acrylate resin according to the present invention can be suitably used as a paint, particularly as a paint for a decorative film for in-mold molding.
In the present specification, "(meth) acrylate" represents acrylate and methacrylate, "(meth) acrylic" represents acrylic and methacrylic, and "(meth) acryloyl" represents acryloyl and methacryloyl.

The weight average molecular weight (Mw) of the ultraviolet curable urethane (meth) acrylate resin according to the present invention is preferably 2,000 to 30,000, more preferably 5,000 to 25,000, and even more preferably 7. It is 000 to 20,000, particularly preferably 9,000 to 15,000. The weight average molecular weight (Mw) can be measured using gel permeation chromatography (GPC). When the weight average molecular weight (Mw) is within the above numerical range, it is excellent in extensibility and can be suitably used as a coating material for an in-mold decorative film.

The viscosity of the ultraviolet curable urethane (meth) acrylate resin according to the present invention at 25 ° C. is preferably 100 to 3,000 mPa · s, more preferably 500 to 2,000 mPa · s, still more preferably 700 to 1. , 500 mPa · s. If the viscosity is within the above numerical range, the processing suitability is excellent.

((A) Polyisocyanate compound)
The polyisocyanate compound of the component (A) is a compound having a total of two or more isocyanate groups and / or substituents containing an isocyanate group in one molecule. As the polyisocyanate compound, one kind may be used, or two or more kinds may be used. In the present invention, isocyanate groups and substituents containing isocyanate groups may be collectively referred to as "isocyanate groups". Further, in the polyisocyanate compound, the isocyanate groups may be the same or different.

Examples of the substituent containing an isocyanate group include an alkyl group having 1 to 5 carbon atoms, an alkenyl group having 1 to 5 carbon atoms or an alkoxy group having 1 to 5 carbon atoms, which contain one or more isocyanate groups. Among these, an alkyl group having 1 to 5 carbon atoms is preferable, and an alkyl group having 1 to 3 carbon atoms is particularly preferable.

The type of polyisocyanate is not particularly limited, and examples thereof include chain aliphatic polyisocyanates, aromatic polyisocyanates, alicyclic polyisocyanates, and even if one of these is used, two or more of them can be combined. May be used. Among these, it is preferable to use an alicyclic polyisocyanate.

The chain aliphatic polyisocyanate is a compound having a chain aliphatic structure and two or more isocyanate groups bonded to the chain aliphatic structure. The chain aliphatic polyisocyanate is preferable from the viewpoint of improving the extensibility of the cured coating film of the ultraviolet curable resin composition. The chain aliphatic structure in the chain aliphatic polyisocyanate is not particularly limited, but is preferably a linear or branched alkylene group having 1 to 6 carbon atoms. Examples of such chain aliphatic polyisocyanates include aliphatic diisocyanates such as tetramethylene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, and dimerate diisocyanate, and aliphatic triisocyanates such as tris (isocyanate hexyl) isocyanurate. Isocyanate can be mentioned. These may be used alone or in combination of two or more.

Aromatic polyisocyanates are compounds having an aromatic structure and two or more isocyanate groups attached to it. The aromatic structure of the aromatic polyisocyanate is not particularly limited, but is preferably an aromatic structure having 6 to 13 carbon atoms. Examples of such aromatic polyisocyanates include aromatic diisocyanates such as tolylene diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate, m-phenylenedi isocyanate, and naphthalene diisocyanate. These may be used alone or in combination of two or more.

The alicyclic polyisocyanate is a compound having an alicyclic structure and two or more isocyanate groups. The alicyclic structure of the component (A) is not particularly limited, but is preferably 5 to 15 carbon atoms, and more preferably 6 or more carbon atoms. Further, the number of carbon atoms is more preferably 14 or less, and particularly preferably 13 or less. Further, the alicyclic structure is preferably a cycloalkylene group. Examples of the polyisocyanate having an alicyclic structure include diisocyanate having an alicyclic structure such as bis (isocyanatemethyl) cyclohexane, cyclohexanediisocyanate, bis (isocyanatecyclohexyl) methane, and isophorone diisocyanate, and tris (isocyanate isophorone) isocyanurate. Examples thereof include triisocyanates having an alicyclic structure of. Among these, isophorone diisocyanate is preferably used in order to form a cured coating film having excellent transparency, extensibility, water repellency, and chemical resistance.

((B) Glycol compound)
The diol compound of the component (B) is preferably a chain aliphatic diol having 2 to 6 carbon atoms, and specifically, ethylene glycol, propylene glycol, 1,3-propanediol, 2-methyl-1,3-. Propylenediol, neopentyl glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 1,2-pentanediol, 1,5-pentanediol, 1 , 2-Hexanediol, 1,6-hexanediol and the like. Among these, ethylene glycol is preferably used in order to form a cured coating film having excellent transparency, extensibility, water repellency, and chemical resistance.

The equivalent ratio of the component (B) to the component (A) is preferably 0.50 to 0.80, more preferably 0.55 to 0.75, and further preferably 0.60 to 0.72. be. When the equivalent ratio of the component (B) to the component (A) is within the above range, the ultraviolet curable urethane (meth) acrylate resin provides a cured coating film having excellent transparency, extensibility, water repellency, and chemical resistance. It becomes easy to form.

((C) (meth) acrylate compound))
The (C) (meth) acrylate compound is a compound having one or more hydroxyl groups and one or more (meth) acryloyl groups in the molecule. As the (meth) acrylate compound, one type may be used alone, or two or more types may be used in combination.

Examples of the component (C) include hydroxyalkyl (meth) acrylates such as 2-hydroxyethyl (meth) acrylate and 2-hydroxypropyl (meth) acrylate and caprolactone adducts thereof (Plaxel FA1, FA2 manufactured by Daicel Co., Ltd.). , Polyethylene glycol mono (meth) acrylate, OH group-terminated polyalkylene glycol mono (meth) acrylate such as polypropylene glycol mono (meth) acrylate, and their ethylene oxide modified products (AM-90G, AM-, manufactured by Shin-Nakamura Chemical Industry Co., Ltd.) 130G, Kyoeisha Chemical Co., Ltd. Light Acrylate EC-A, MTG-A, EHDG-AT, etc.), Glycerin Mono (Meta) Acrylate (Nichiyu Co., Ltd. Blemmer GLM, etc.), Glycerindi (Meta) Acrylate (Toa Synthetic Co., Ltd.) Aronix MT3560 manufactured by the company) Isocyanuric acid (EO-modified) diacrylate (Aronix M-313, 315 manufactured by Toa Synthetic Co., Ltd.), Pentaerythritol tri (meth) acrylate (Viscoat 300 manufactured by Osaka Organic Chemical Industry Co., Ltd., Toa Synthetic Co., Ltd.) Aronix M-305, M-306, MT-3548 manufactured by Kyoeisha Chemical Co., Ltd., NK ester A-TMM-3L manufactured by Shin-Nakamura Chemical Industry Co., Ltd.), Dipentaerythritol penta (meth) Acrylate (Aronix M-400, M-402, M-403, MT-3549 manufactured by Toa Synthetic Co., Ltd., Light Acrylate DPE-6A manufactured by Kyoeisha Chemical Co., Ltd., NK Ester A-DPH manufactured by Shin-Nakamura Chemical Industry Co., Ltd., etc.) Be done.

Among the above (meth) acrylates, it is particularly preferable to use pentaerythritol triacrylate, which may contain pentaerythritol monoacrylate, pentaerythritol diacrylate, and pentaerythritol tetraacrylate. The ultraviolet curable urethane (meth) acrylate resin using these (meth) acrylate compounds facilitates the formation of a cured coating film having excellent transparency, extensibility, water repellency and chemical resistance.

The equivalent ratio of the component (C) to the component (A) is preferably 0.25 to 0.50, more preferably 0.25 to 0.45, and further preferably 0.30 to 0.40. be. When the equivalent ratio of the component (C) to the component (A) is within the above range, the ultraviolet curable urethane (meth) acrylate resin provides a cured coating film having excellent transparency, extensibility, water repellency, and chemical resistance. It becomes easy to form.

((D) Hydroxyl group-containing fluorine compound)
The hydroxyl group-containing fluorine-containing compound is a compound having at least a hydroxyl group and fluorine (fluorine-containing group), and may further have a reactive group. Examples of the reactive group include (meth) acryloyl group, vinyl group, allyl group, styryl group and the like.

As the hydroxyl group-containing fluorine-containing compound, a hydroxyl group-containing fluorine-containing oligomer can be used. The hydroxyl group-containing fluorine-containing oligomer includes a unit derived from a fluoroolefin, a unit derived from a monomer having a hydroxyl group (hereinafter referred to as “monomer (m1)”) that can be copolymerized with a fluoroolefin, and, if necessary. A hydroxyl group-containing fluorine-containing oligomer having a unit derived from a fluoroolefin and a monomer other than the monomer (m1) (hereinafter, referred to as “monomer (m2)”) is preferable.

Further, the hydroxyl group-containing fluorine-containing compound may be a hydroxyl group-containing fluorine-containing oligomer in which a hydroxyl group is introduced by the reactive group conversion of the oligomer. The fluorine-containing oligomer containing a hydroxyl group includes a unit derived from a fluoroolefin, a unit derived from a monomer having a reactive group other than the hydroxyl group, and, if necessary, the fluorine-containing oligomer having the monomer (m2). A fluorine-containing oligomer obtained by reacting a compound having a hydroxyl group with a reactive group that reacts with the reactive group can be used.

The monomer (m1) is a monomer having a hydroxyl group, and may further have a reactive group other than the hydroxyl group. Examples of the monomer having a hydroxyl group include hydroxyalkyl vinyl ether such as allyl alcohol, 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether and cyclohexanediol monovinyl ether, hydroxyalkyl allyl ether such as 2-hydroxyethyl allyl ether, and hydroxypropionic acid. Examples thereof include vinyl hydroxyalkanoate such as vinyl, hydroxyalkyl (meth) acrylate such as hydroxyethyl (meth) acrylate, and the like. One type of monomer (m1) may be used alone, or two or more types may be used in combination. You may.

The monomer (m2) is a monomer having no hydroxyl group and may have a reactive group. Examples of the monomer (m2) include vinyl ether, allyl ether, carboxylic acid vinyl ester, carboxylic acid allyl ester, and olefin. Examples of the vinyl ether include alkyl vinyl ethers such as nonyl vinyl ether, 2-ethylhexyl vinyl ether, hexyl vinyl ether, ethyl vinyl ether, n-butyl vinyl ether and tert-butyl vinyl ether, and cycloalkyl vinyl ethers such as cyclohexyl vinyl ether. Further, the monomer (m2) may have the above-mentioned reactive group. As the monomer (m2), one type may be used alone, or two or more types may be used in combination.

The content of the component (D) in the ultraviolet curable urethane (meth) acrylate resin is preferably 0.01 to 10.0 mass with respect to the total amount of the component (A), the component (B) and the component (C). %, More preferably 0.5 to 5.0% by mass. When the content of the component (D) is within the above range, the ultraviolet curable urethane (meth) acrylate resin can easily form a cured coating film having excellent transparency, extensibility, water repellency, and chemical resistance.

Specific examples of the components (D) that are commercially available include Ftergent 710FM, Futtergent 601ADH2 (trade name, manufactured by Neos Co., Ltd.), Megafuck F-558, Megafuck F-561, and Megafuck F. -562, Mega Fvck F-563, Mega Fvck F-569, Mega Fvck F-576 (trade name, manufactured by DIC), Surflon S-647, Surflon S-651, Surflon S-656, Surflon S-693 ( Product name, above, manufactured by AGC Seimi Chemical Co., Ltd.) and the like.

(reaction)
The ultraviolet curable urethane (meth) acrylate resin according to the present invention is obtained by reacting the above components (A) to (D), and reaction conditions such as temperature and time can be appropriately set. For example, first, a polymerization inhibitor such as BHT, a tin catalyst such as dibutyltin dilaurate, and components (A) and (B) are added to the reactor and reacted at 60 to 70 ° C. for 1 to 2 hours. After that, the component (D) is added and reacted at 60 to 70 ° C. for 1 to 2 hours. Then, the component (C) is added and reacted at 80 to 90 ° C. for 2 to 4 hours to obtain an ultraviolet curable urethane (meth) acrylate resin according to the present invention. The component (D) and the component (C) may be added at the same time, but if the reactivity of the component (C) is high, it is not better to add the component (D) before the component (C). This is preferable because the component (D) of the reaction does not easily remain. The end point of the reaction can be confirmed by the disappearance of the peak derived from the isocyanate group by infrared absorption analysis.

(Ultraviolet curable resin composition)
The ultraviolet curable resin composition according to the present invention (hereinafter, may be simply referred to as “resin composition”) contains at least the above ultraviolet curable urethane (meth) acrylate resin and a photopolymerization initiator. In the resin composition according to the present invention, the coating film formed by curing is excellent in transparency, extensibility, water repellency, and chemical resistance. Such a resin composition can be suitably used as a paint, particularly as a paint for a decorative film for in-mold molding.

(Photopolymerization initiator)
The photopolymerization initiator is not particularly limited, and conventionally known photopolymerization initiators for ultraviolet curing can be used. Examples of the photopolymerization initiator include an acetophenone-based polymerization initiator, a phosphine oxide-based polymerization initiator, a benzoylformate-based polymerization initiator, a thioxanthone-based polymerization initiator, an oxime ester-based polymerization initiator, and a hydroxybenzoyl-based polymerization initiator. , Benzophenone-based polymerization initiator, α-aminoalkylphenone-based polymerization initiator and the like.

Examples of the acetophenone-based polymerization initiator include acetophenone, 3-methylacetophenone, benzyldimethylketal, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropane-1-one, and 2-methyl-1- [4-. (Methylthio) Phenyl-2-morpholinopropane-1-one, 2-hydroxy-2-methyl-1-phenylpropane-1-one and the like can be mentioned.
Examples of the phosphine oxide-based polymerization initiator include bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide and 2,4,6-trimethylbenzoyldiphenylphosphine oxide.
Examples of the benzoylformate-based polymerization initiator include methylbenzoylformate and the like.
Examples of the thioxanthone-based polymerization initiator include isopropylthioxanthone and the like.
Oxime ester-based polymerization initiators include 1,2-octanedione, 1- [4- (phenylthio)-, 2- (O-benzoyloxime)] and etanone, 1- [9-ethyl-6- (2-). Methylbenzoyl) -9H-carbazole-3-yl]-, 1- (O-acetyloxime) and the like can be mentioned.
Examples of the hydroxybenzoyl-based polymerization initiator include 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexylphenyl ketone, benzoin alkyl ether and the like.
Examples of the benzophenone-based polymerization initiator include benzophenone, 4-chlorobenzophenone, 4,4'-diaminobenzophenone and the like.
Examples of the α-aminoalkylphenone-based polymerization initiator include 2-methyl-1- (4-methylthiophenyl) -2-morpholinopro-butanone-1 and 2- (dimethylamino) -2-[(4-methylphenyl). Methyl] -1- [4- (4-morpholinyl) phenyl] -1-butanone and the like can be mentioned.

The content of the photopolymerization initiator is preferably 0.1% by mass or more and 15.0% by mass or less, more preferably 1 with respect to the total amount of the non-volatile components of the resin composition from the viewpoint of curability and transparency. It is 0.0% by mass or more and 12.0% by mass or less, and more preferably 2.0% by mass or more and 10.0% by mass or less.

(Other ingredients)
The resin composition according to the present invention may contain an ultraviolet curable resin other than the ultraviolet curable urethane (meth) acrylate resin, a (meth) acrylate monomer, and a thermoplastic resin as long as the object of the present invention is not impaired. It may contain other components other than the photopolymerization initiator. Other components include antistatic agents, polymerization inhibitors, non-reactive diluents, matting agents, defoamers, dispersants, antisettling agents, leveling agents, dispersants, heat stabilizers, UV absorbers, photostabilizers. Agents, adhesion improvers, photosensitizers, antibacterial agents, fungicides, antiviral agents, silane coupling agents, plasticizers and the like can be blended as needed.

<Preparation method of resin composition>
The resin composition according to the present invention can be obtained by mixing and stirring each of the above components using a conventionally known device such as a mixer, a disperser, or a stirrer. Examples of such an apparatus include a mixing / dispersing mill, a homodisper, a mortar mixer, a roll, a paint shaker, a homogenizer, and the like.

The viscosity of the resin composition (resin solution) at 25 ° C. is preferably 100 to 3,000 mPa · s, more preferably 500 to 2,000 mPa · s, still more preferably 700 to 1,500 mPa · s. be. A B-type viscometer can be used to measure the viscosity. If the viscosity is within the above numerical range, the processing suitability is excellent.

In the present invention, the resin composition can be diluted with a solvent, if necessary, such as adjusting the viscosity to be suitable for coating. The solvent is not particularly limited as long as it dissolves the resin component in the resin composition. Specifically, aromatic hydrocarbons (eg, toluene, xylene and ethylbenzene), esters or ether esters (eg, ethyl acetate, butyl acetate and methoxybutyl acetate), ethers (eg, diethyl ether, tetrahydrofuran, ethylene glycol monoethyl). Ethers, ethylene glycol monobutyl ethers, propylene glycol monomethyl ethers and diethylene glycol monoethyl ethers), ketones (eg acetone, methyl ethyl ketones, methyl isobutyl ketones, di-n-butyl ketones and cyclohexanones), alcohols (eg methanol, ethanol, n). -Or i-propanol, n-, i-, sec- or t-butanol, 2-ethylhexyl alcohol and benzyl alcohol), amides (eg, dimethylformamide, dimethylacetamide, N-methylpyrrolidone, etc.), sulfoxides (eg, dimethyl). Sulfoxide), water and a mixed solvent of two or more of these, and the like.

(Curing coating film)
When the thickness of the cured coating film formed from the resin composition according to the present invention is 3 μm, the haze measured according to JIS K 7136 is preferably less than 1%, preferably 0.7% or less. Is more preferable, and 0.5% or less is further preferable. Further, the cured coating film having a thickness of 3 μm preferably has a total light transmittance of 90% or more, more preferably 91% or more, as measured in accordance with JIS K 7631-1. If the haze and the total light transmittance are within the above ranges, the transparency is excellent.

When the thickness of the cured coating film formed from the resin composition according to the present invention is 3 μm, the extensibility measured at room temperature is preferably 100% or more, more preferably 115% or more, 130. % Or more is even more preferable, and 140% or more is even more preferable. When the value of extensibility is within the above range, the extensibility is excellent, and it can be suitably used as a paint for a decorative film for in-mold molding. The detailed measurement method of extensibility will be described later.

The cured coating film formed from the resin composition according to the present invention preferably has a water contact angle of 90 ° or more, more preferably 95 ° or more, and even more preferably 100 ° or more. When the value of the water contact angle is within the above range, the water repellency is excellent and the antifouling property can be improved.

The cured coating film formed from the resin composition according to the present invention preferably has a water contact angle difference of less than 10 ° before and after the moisture resistance test at a temperature of 85 ° C., a humidity of 85% RH, and 500 hours, preferably less than 7 °. More preferably, less than 5 °, even more preferably less than 3 °. When the numerical value of the water contact angle difference before and after the moisture resistance test is within the above range, the moisture resistance is excellent and the stain resistance can be maintained for a long period of time.

<Base material with coating film>
The base material with a coating film according to the present invention comprises the above-mentioned cured coating film on the base material. FIG. 1 shows a schematic cross-sectional view of a substrate with a coating film according to the present invention. The coated base film 10 shown in FIG. 1 includes a cured coating film 12 on one surface of the base material 11.

The base material in the base material with a coating film according to the present invention is not particularly limited, and conventionally known base materials can be used. For example, when the base material with a coating film is a decorative film for in-mold molding, a thermoplastic resin film such as a polyester film, a polyolefin film, a nylon film, a polycarbonate film, or a polymethyl methacrylate film is used as the base material. be able to.

The cured coating film on the coated substrate according to the present invention is suitable as the outermost protective layer in applications that need to be applied in multiple layers.

The coated substrate according to the present invention may further include other layers in applications that need to be applied in multiple layers. For example, the coated substrate according to the present invention may have another layer between the substrate and the cured coating. Examples of other layers in the substrate with a coating film according to the present invention include an intermediate coating layer and a primer layer. These other layers may be composed of only one layer or may be composed of multiple layers.

<Manufacturing method of substrate with coating film>
The coated substrate according to the present invention comprises a coating step of applying the above resin composition to at least one surface of the substrate.
After the coating step, a curing step of curing the above fat composition by irradiation with ultraviolet rays to form a cured coating film, and a curing step of forming a cured coating film.
Is included. Hereinafter, each step will be described in detail.

(Applying process)
The coating step is a step of coating the above resin composition on one side of the base material by a conventionally known method. For coating, for example, a coating machine such as a bar coater, a gravure coater, a roll coater (natural roll coater, reverse roll coater, etc.), an air knife coater, a spin coater, a blade coater, or the like can be used. Among these, the coating method using a gravure coater is preferable from the viewpoint of workability and productivity.

The coating film thickness is preferably 0.5 to 50 μm as the film thickness after curing and drying. A more preferable upper limit is 30 μm from the viewpoint of drying property and curability, and a further preferable lower limit is 1 μm from the viewpoint of water repellency and chemical resistance.

When the resin composition is diluted with a solvent and used, it is preferable to dry it after coating. Examples of the drying method include hot air drying (dryer or the like). The drying temperature is preferably 10 to 200 ° C., a more preferable upper limit is 150 ° C. from the viewpoint of smoothness and appearance of the coating film, and a further preferable lower limit is 30 ° C. from the viewpoint of drying speed.

(Curing process)
The curing step is a step of irradiating the coated surface of the base material with ultraviolet rays to cure the coated resin composition to form a cured coating film. Examples of the method of curing with ultraviolet rays include a method of irradiating ultraviolet rays using a high-pressure mercury lamp, a metal halide lamp, a xenon lamp, a chemical lamp, a UV-LED, or the like that emits light in the wavelength range of 200 to 500 nm. The dose of ultraviolet rays, a flexible viewpoint of curability and cured product of the resin composition, preferably 100~3,000mJ / cm ^2, more preferably 200~1,000mJ / cm ^2.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples.

<Synthesis of UV curable urethane (meth) acrylate resin>
First, the following raw materials were prepared for the synthesis of ultraviolet curable urethane (meth) acrylate resin.
-(A) component: isophorone diisocyanate- (B) component: ethylene glycol- (C) component: pentaerythritol triacrylate (hydroxyl value 280)
(D1) component: hydroxyl group and fluorine-containing group-containing reactive oligomer (manufactured by Neos, trade name: Futergent 710FM, non-volatile component: 50% by mass)
(D2) component: hydroxyl group, fluorine-containing group, and ultraviolet-reactive group-containing reactive oligomer (manufactured by Neos, trade name: Futergent 601ADH2, non-volatile component: 25% by mass)
(D3) component: hydroxyl group, fluorine-containing group, and lipophilic group-containing oligomer (manufactured by DIC Corporation, trade name: Megafuck F-576, non-volatile component: 100% by mass)
(D4) component: hydroxyl group, fluorine-containing group, and lipophilic group-containing oligomer (manufactured by DIC Corporation, trade name: Megafuck F-561, non-volatile component: 100% by mass)
-Other components: Hydroxyl-containing polydimethylsiloxane (manufactured by TEGO, trade name: PROTECT 5000N, non-volatile component: 100% by mass)

Put 111 g of isophorone diisocyanate, 21.7 g of ethylene glycol, 98.4 g of methyl ethyl ketone, and 0.389 g of dibutyltin dilaurate in a four-necked flask equipped with a stirrer, a reflux condenser, and a thermometer, and put them in an oil bath up to 70 ° C. The reaction was carried out for 1 hour while heating. Then, 5.9 g of a hydroxyl group- and fluorine-containing group-containing reactive oligomer (Futergent 710FM) was added, and the mixture was reacted for 1 hour. Then, 64 g of a mixture of (meth) acrylate compounds, 0.02 g of 4-methoxyphenol and 0.06 g of dibutylhydroxytoluene were added, the temperature was raised to 80 ° C. in an oil bath, and the mixture was reacted for 4 hours. The end point of the reaction was confirmed by infrared absorption analysis by the disappearance of the peak derived from the isocyanate group. After completion of the reaction, 98.4 g of propylene glycol monomethyl ether was added to obtain a resin solution containing a fluorine-containing urethane acrylate resin (2).

Further, a resin solution containing an ultraviolet curable urethane (meth) acrylate resin (1) and (3) to (9) was prepared in the same manner as in Example 1 except that each component was reacted according to the formulation shown in Table 1. Obtained.

<Evaluation of UV curable urethane (meth) acrylate resin>
(Weight average molecular weight)
The ultraviolet curable urethane (meth) acrylate resins (1) to (9) synthesized above were measured by gel permeation chromatography under the following measurement conditions, and the measurement results are shown in Table 1.
[Measurement condition]
・ Equipment: "HLC-8220" (manufactured by Tosoh Corporation)
-Column: One "TSKgel Super H4000" and two "TSKgel Super H2000" are connected (both manufactured by Tosoh Corporation, inner diameter 6 mm x length 15 cm).
-Eluent: Tetrahydrofuran 99% (Stabilized with BHT)
・ Flow velocity: 0.5 mL / min
Detector: Differential refractometer (RI) built into the HLC-8220 device
・ Column constant temperature bath temperature: 40 ° C
-Standard substance: Standard polystyrene-Sample preparation method: Amount of resin solution containing each resin (1) to (9) in a sample tube
Remove and add tetrahydrofuran and dilute about 100 times.

(viscosity)
The viscosities of the resin solutions containing the ultraviolet curable urethane (meth) acrylate resins (1) to (9) synthesized above were measured under the following measurement conditions. The measurement results are shown in Table 1.
[Measurement condition]
・ Equipment: TV-22 type viscometer (manufactured by Toki Sangyo)
-Rotor used: 1 ° 34'x R24
・ Rotor rotation speed: 20 rpm
・ Measurement temperature: 25 ° C

(Non-volatile component)
The resin solution containing the ultraviolet curable urethane (meth) acrylate resins (1) to (9) synthesized above was subjected to the conditions of 160 ° C. for 1 hour using (Isuzu Seisakusho Co., Ltd., model number: VTFP-64-1S). The amount of non-volatile component (%) was measured from the mass difference before and after the test. The measurement results are shown in Table 1.

<Preparation of UV curable resin composition>
[Examples 1 to 7]
In 32.0 parts by mass of methyl ethyl ketone, 65.0 parts by mass of any of the ultraviolet curable urethane (meth) acrylate resins (2) to (8) shown in Table 2 and a photopolymerization initiator (manufactured by IGM Resins). Trade name: Omnirad 184) was added in an amount of 3.0 parts by mass and dissolved to obtain an ultraviolet curable resin composition.

[Comparative Example 1]
In 32.0 parts by mass of methyl ethyl ketone, 65.0 parts by mass of ultraviolet curable urethane (meth) acrylate resin (1) and 3.0 parts by mass of a photopolymerization initiator (manufactured by IGM Resins, trade name: Omnirad 184). And was added and dissolved to obtain an ultraviolet curable resin composition.

[Comparative Examples 2 to 5]
In the amount of methyl ethyl ketone shown in Table 2, 65.0 parts by mass of an ultraviolet curable urethane (meth) acrylate resin (1) and a photopolymerization initiator (manufactured by IGM Resins, trade name: Omnirad 184) are 3.0. A UV-curable resin is obtained by adding and dissolving a part by mass and a fluorine-based additive (hydroxyl group-containing group-containing reactive oligomer, manufactured by Neos Co., Ltd., trade name: Futergent 710FM) shown in Table 2. The composition was obtained.

[Comparative Example 6]
In 32.0 parts by mass of methyl ethyl ketone, 65.0 parts by mass of ultraviolet curable urethane (meth) acrylate resin (9) and 3.0 parts by mass of a photopolymerization initiator (manufactured by IGM Resins, trade name: Omnirad 184). And was added and dissolved to obtain an ultraviolet curable resin composition.

<Manufacturing of base material with coating film>
[Examples 1 to 7, Comparative Examples 1 to 6]
Each ultraviolet curable urethane (meth) acrylate resin prepared in Examples 1 to 7 and Comparative Examples 1 to 6 above was applied to a PET film (manufactured by Toyobo Co., Ltd., trade name: Cosmoshine A4300) with a dry film thickness of about 3 μm. It was applied once so as to be. Subsequently, the coating film was cured by irradiating with ultraviolet rays with a high-pressure mercury lamp (irradiation amount: 300 mJ / cm ² ) to form a cured coating film, and a substrate with a coating film was obtained.

<Performance evaluation>
(Appearance of coating film)
The state of the coating film of the substrate with a coating film manufactured above was visually confirmed. The confirmed results were used to determine the appearance of the coating film according to the following criteria. The determination results are shown in Table 3.
[criterion]
〇: It was good.
X: The leveling was poor.

(optical properties)
For the base material with a coating film manufactured above, the haze (HZ) was measured in accordance with JIS K 7136 using a haze meter (manufactured by Nippon Denshoku Industries Co., Ltd., model number: NDH4000), and JIS K 7631-1 The total light transmittance (TT) was measured according to the above. The measurement results are shown in Table 3. In addition, the optical characteristics were determined according to the following criteria.
[HZ criteria]
〇: It was less than 1%.
X: 1% or more.
[TT judgment criteria]
〇: It was 90% or more.
X: It was less than 90%.

(Extension)
For the substrate with a coating film produced above, a strip-shaped test piece having a size of 15 mm × 150 mm was prepared. Subsequently, at room temperature, the test piece was pulled with a tensile tester (manufactured by Shimadzu Corporation, model number: EZ-L) under the conditions of (distance between chucks: 100 mm, tensile speed: 10 mm / min), and the coating film was visually coated. The elongation rate until cracks were formed in the room temperature was measured. The measurement results are shown in Table 3. In addition, the extensibility was determined according to the following criteria.
[criterion]
⊚: It was 130% or more.
〇: It was 100% or more and less than 130%.
X: It was less than 100%.

(Water repellency)
The water contact angle of the coated substrate produced above was measured using a contact angle meter (manufactured by Kyowa Interface Science Co., Ltd., model number: DropMaster DM500). For the measurement, 1 μL of pure water was dropped and the value after 10 seconds was confirmed. The measurement results are shown in Table 3. In addition, the water repellency was determined according to the following criteria.
[criterion]
⊚: It was 100 ° or more.
〇: It was 90 ° or more and less than 100 °.
X: It was less than 90 °.

(Water repellency after moisture resistance test)
The substrate with the coating film manufactured above is placed in a low-temperature constant temperature and humidity chamber (HIFLEX NEO FX420N manufactured by Kusumoto Kasei Co., Ltd.) set at a temperature of 85 ° C. and a humidity of 85% RH, and then the test piece is taken out after standing for 500 hours. rice field. The water contact angle of the taken-out test piece was measured using a contact angle meter (manufactured by Kyowa Interface Science Co., Ltd., model number: DropMaster DM500). For the measurement, 1 μL of pure water was dropped and the value after 10 seconds was confirmed. Table 3 shows the measurement results and the difference in water contact angle before and after the moisture resistance test. In addition, the water repellency after the moisture resistance test was determined according to the following criteria.
[criterion]
〇: The difference in water contact angle before and after the moisture resistance test was less than 5 °.
Δ: The difference in water contact angle before and after the moisture resistance test was 5 ° or more and less than 10 °.
X: The difference in water contact angle before and after the moisture resistance test was 10 ° or more.

(chemical resistance)
0.5 g of Neutrogena sunscreen cream (SPF45) was applied to an area of 5 cm × 5 cm on the substrate with a coating film produced above. Subsequently, the film was allowed to stand at 80 ° C. for 4 hours and then washed, and the state of the coating film was visually confirmed. The confirmed results were judged according to the following criteria. The determination results are shown in Table 3.
[criterion]
〇: There was no abnormality.
X: Whitening or blistering occurred.

11 Base material with coating film 12 Base material 13 Cured coating film

Claims (13)

(A) Polyisocyanate compound,
(B) Glycol compound,
(C) (meth) acrylate compound, and (D) hydroxyl group-containing fluorine compound,
UV curable urethane (meth) acrylate resin obtained by reacting with. The ultraviolet curable urethane (meth) acrylate resin according to claim 1, which contains an alicyclic polyisocyanate as a component (A). The ultraviolet curable urethane (meth) acrylate resin according to claim 1 or 2, which contains a chain aliphatic diol having 2 to 6 carbon atoms as a component (B). The ultraviolet curable urethane (meth) acrylate resin according to any one of claims 1 to 3, which contains pentaerythritol triacrylate as a component (C). The ultraviolet curable urethane (meth) acrylate resin according to any one of claims 1 to 4, wherein the equivalent ratio of the component (B) to the component (A) is 0.50 to 0.80. The ultraviolet curable urethane (meth) acrylate resin according to any one of claims 1 to 5, wherein the equivalent ratio of the component (C) to the component (A) is 0.20 to 0.50. The ultraviolet curable type according to any one of claims 1 to 5, wherein the amount of the component (D) is 0.01 to 10.0% by mass with respect to the total amount of the components (A), (B) and (C). Urethane (meth) acrylate resin. An ultraviolet curable resin composition comprising the ultraviolet curable urethane (meth) acrylate resin according to any one of claims 1 to 7 and a photopolymerization initiator. The ultraviolet curable resin composition according to claim 8, which is used as a paint. The ultraviolet curable resin composition according to claim 9, wherein the paint is used for a decorative film for in-mold molding. A cured coating film formed from the ultraviolet curable resin composition according to any one of claims 8 to 10. A substrate with a coating film, which comprises the cured coating film according to claim 11 on the substrate. A coating step of applying the ultraviolet curable resin composition according to any one of claims 8 to 10 to at least one surface of a substrate,
After the coating step, a curing step of curing the ultraviolet curable resin composition by ultraviolet irradiation to form a cured coating film, and a curing step.
A method for producing a base material with a coating film.

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