JP6533046B2 - Coating composition and hard coat film using the same - Google Patents

Description

  The present invention relates to a coating composition and a hard coat film using the same.

  Conventionally, in order to prevent the surface of glass and resin moldings from being damaged, a coating paint made of energy ray-curable resin or the like is applied to these surfaces to provide a hard coat film, or a hard coat layer on a resin film The hard coat film provided with is stuck to the said glass or resin molded object, and is used.

  The above hard coat film and hard coat film are widely used in applications such as displays, touch panels, and display screens of mobile phones etc. In particular, mobile products such as mobile phones and smartphones have an opportunity to be used outdoors It has increased. As such a hard coat film for outdoor use, a film which does not turn yellow even when exposed to ultraviolet rays for a long time is required. Therefore, it has been proposed to add an ultraviolet light absorber or a light stabilizer to the hard coat layer for the purpose of imparting weather resistance (Patent Document 1).

JP-A-9-157315

  However, in the case of the hard coat film proposed in Patent Document 1, the addition of the ultraviolet absorber and the light stabilizer causes the inhibition of curing, and the film hardness, the scratch resistance and the adhesion to the substrate decrease. It is happening. This problem is significant when large amounts of UV absorbers and light stabilizers are added to accommodate higher levels of weatherability.

  In addition, in order to reduce the production cost, the above-mentioned mobile products often differ in the production base of each component and the assembly base of mobile products, and the production of various components, long-term storage of mobile products under high temperature and humidity environment during transportation and mobile products In consideration of the properties, the hard coat layer must be one that does not deteriorate in a high temperature and high humidity environment (scratch resistance). Furthermore, even in such an environment, it is required to have excellent substrate adhesion which does not cause peeling between the hard coat layer and the transparent support.

  Therefore, an object of the present invention is to provide a coating composition for hard coat film and a hard coat film having good weatherability while improving the above-mentioned defects and maintaining excellent scratch resistance and substrate adhesion. . Furthermore, another object of the present invention is to provide a coating composition for hard coat film and a hard coat film which are excellent in adhesion to a substrate even after storage in a high temperature and high humidity environment.

The inventors of the present invention conducted intensive studies to solve the above problems, and as a result, an energy ray curable (type) (meth) acrylate monomer having a specific molecular weight, a specific energy ray curable functional group number and a hydroxyl group number, The inventors have found that the above problems can be solved by using a coating composition containing an energy ray-curable (meth) acrylate oligomer having a molecular weight and a specific ultraviolet absorber, and the present invention has been accomplished.
(Meth) acrylate refers to acrylate or methacrylate.

  That is, according to the present invention, the coating composition and the hard coat film of the constitution shown below are provided.

  The coating composition of the present invention has (A) a weight average molecular weight of 250 to 1000, an energy ray curable functional group number of 2 to 9 and an energy ray curable (meth) acrylate having a hydroxyl group number of 1 or less. A monomer, (B) an energy ray-curable functional group-containing ultraviolet absorber, and (C) an energy ray-curable oligomer having a weight average molecular weight of 1,500 or more and 20,000 or less.

  The coating composition of the present invention comprises (E1) a photopolymerization initiator having a maximum absorbance of 0.1 or more in a wavelength range of 340 nm to 400 nm of a 0.01% by mass methanol solution or acetonitrile solution (E2) It is preferable to further include a photopolymerization initiator having a maximum absorbance of 0.1 or more in a wavelength range of 220 nm to 280 nm of a 0.001% by mass methanol solution or acetonitrile solution.

  In the coating composition of the present invention, the mass ratio of the (A) component to the (C) component ((A) component: (C) component) is preferably 3: 97 to 50: 50.

  Furthermore, in the coating composition of the present invention, the component (B) is preferably a UV absorber having a maximum absorbance of 0.6 or more in a wavelength range of 280 nm to 370 nm of a 0.0619 mmol / l dichloromethane solution.

  The hard coat film of the present invention is characterized by having a hard coat layer obtained from the above-mentioned coating composition on at least one surface of a transparent support.

  In the hard coat film of the present invention, the thickness of the hard coat layer is preferably 0.5 μm or more and 20 μm or less.

  Further, in the hard coat film of the present invention, the base material adhesion between the hard coat layer and the transparent support is preferably 90/100 or more based on JIS K5400.

  In addition, the hard coat film of the present invention has a temperature of 60 ° C. and a relative humidity of 90%. H. The substrate adhesion between the hard coat layer and the transparent support after the moisture resistance test of being left in an environment of 550 hours is preferably 90/100 or more based on JIS K5400.

  In addition, the hard coat film of the present invention preferably has a yellowing factor (Δb) of less than 1 after 12 cycles of the weather resistance test specified in ASTM G-154.

  ADVANTAGE OF THE INVENTION By this invention, the coating composition for hard-coat films which is excellent in abrasion resistance, a weather resistance, and base-material adhesiveness, and a hard-coat film can be provided.

Embodiments of the present invention will be described in detail below.
(1) Coating Composition The coating composition of the present invention has an (A) weight average molecular weight of 250 or more and 1,000 or less, an energy ray curable functional group number of 2 or more and 9 or less, and an hydroxyl group number of 1 or less. A curable (meth) acrylate monomer, (B) an energy ray-curable functional group-containing ultraviolet absorber, and (C) an energy ray-curable oligomer having a weight average molecular weight of 1,500 or more and 20,000 or less.
Each component will be described below.

(A) Energy ray curable (meth) acrylate monomer The coating composition of the present invention has a weight average molecular weight of 250 or more and 1000 or less, an energy ray curable functional group number of 2 or more and 9 or less, and a hydroxyl number of 1 It is essential to use the energy ray curable (meth) acrylate monomer which is the following. By using such a monomer, hardness, abrasion resistance and substrate adhesion can be improved. In particular, it is possible to effectively improve the substrate adhesion in a high temperature and high humidity environment.

  By setting the weight average molecular weight of the (meth) acrylate monomer to 250 or more, it is possible to give filmability when it is formed into a hard coat layer. For this reason, while base-material adhesiveness improves, it can suppress the fall of abrasion resistance. In addition, volatilization of unreacted monomers due to heating can be prevented in the process of producing the hard coat layer. On the other hand, by setting the weight average molecular weight to 1000 or less, the molecular weight is not too large, so that the component (A) can be easily disposed in the interstices of the components (B) and (C) as described later. Therefore, the crosslinking efficiency is improved, the adhesion to the substrate is improved, and the decrease in the abrasion resistance due to the addition of the ultraviolet absorber can be suppressed. Moreover, when it is set as the coating liquid for hard-coat layers, it can prevent increasing in viscosity. The weight average molecular weight of the (meth) acrylate monomer can be confirmed by gel permeation chromatography (GPC).

By setting the number of hydroxyl groups of the (meth) acrylate monomer to 1 or less, it is possible to suppress a decrease in substrate adhesion in a high temperature and high humidity environment. In the present invention, as described above, since an energy ray curable monomer having a weight average molecular weight of 250 or more and 1000 or less is used, sufficient substrate adhesion can be obtained without having a hydroxyl group. When the (meth) acrylate monomer has one hydroxyl group, the adhesiveness is improved by the reaction between the above-described transparent support, that is, the acidic functional group present on the surface of the glass or resin substrate and the hydroxyl group. Therefore, substrate adhesion can be further improved.
The use of a monomer having two or more hydroxyl groups is advantageous in that the adhesion is improved by the reaction with the functional group on the surface of the transparent support. However, since the unreacted hydroxyl group remains in the hard coat layer, the adhesion of the substrate is reduced under the influence of the residual hydroxyl group in a high temperature and high humidity environment. In the present invention, since the number of hydroxyl groups of the (meth) acrylate monomer is 1 or less, there is almost no unreacted hydroxyl group after the curing reaction, and therefore the adhesion of the substrate decreases due to the residual hydroxyl group even under high temperature and humidity conditions. Can be suppressed.

In addition, by setting the number of energy ray curable functional groups of the (meth) acrylate monomer to 2 or more and 9 or less, a hard coat film having high hardness and excellent scratch resistance and substrate adhesion can be obtained. By using a (meth) acrylate monomer having two or more energy ray-curable functional groups, the crosslinking reaction with the components (B) and (C) proceeds more effectively, thereby improving the substrate adhesion. It is possible to suppress the decrease in scratch resistance caused by the addition of the ultraviolet light absorber. When the number of energy ray curable functional groups of the (meth) acrylate monomer is 1 or less, it is difficult to obtain a hard coat film having high hardness and excellent scratch resistance. In addition, when such a (meth) acrylate monomer is used, the crosslinking reaction does not proceed sufficiently, so that the obtained hard coat film is easily deteriorated by ultraviolet light, and it is difficult to obtain excellent weather resistance. Furthermore, since the crosslinking reaction does not proceed sufficiently, it is also difficult to obtain excellent substrate adhesion.
On the other hand, when a (meth) acrylate monomer having an energy ray curable functional group number of 9 or less is used, the component (A) is easily disposed in the intermolecular space of the components (B) and (C), and the crosslinking efficiency is also improved. The adhesion to a substrate is improved, and a decrease in scratch resistance due to the addition of an ultraviolet absorber can be suppressed. When a (meth) acrylate monomer having an energy ray-curable functional group number of more than 9 is used, an excessive crosslinking reaction between the components (A) is likely to proceed, so the components (A) are components (B) and (C). It is difficult to obtain a hard coat film having excellent scratch resistance and substrate adhesion, since it is difficult to be disposed in a molecular gap and the crosslink density does not easily increase.

  As (A) (meth) acrylate monomers as described above, dipentaerythritol hexa (meth) acrylate, trimethylol propane (meth) acrylate, pentaerythritol tri (meth) acrylate, ethylene glycol di (meth) acrylate, tri Ethylene glycol divinyl ether, tetraethylene glycol (meth) acrylate, tripropylene glycol (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di ( Meta) acrylate, trimethylolpropane trioxyethyl (meth) acrylate, tris (2-hydroxyethyl) isocyanurate tri (meth) acrylate, dipentaerythritol poly Acrylate, dipentaerythritol hexaacrylate, tricyclodecane dimethanol diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, trimethylolpropane triacrylate, ditrimethylolpropane tetraacrylate and the like can be mentioned. Among them, dipentaerythritol hexaacrylate, pentaerythritol triacrylate and pentaerythritol tetraacrylate are preferable because they have good adhesion to the transparent support and high reactivity.

(B) UV Absorber The coating composition of the present invention comprises an energy ray-curable functional group-containing UV absorber. Usually, in order to obtain the weather resistance of the hard coat layer and the hard coat film, a UV absorber is added to the coating composition. In the present invention, since the energy ray-curable functional group-containing ultraviolet ray absorber is used as the ultraviolet ray absorber, the crosslinking reaction between the component (A) and the component (C) described later proceeds effectively. Therefore, the crosslink density can be improved, and the decrease in scratch resistance due to the addition of the ultraviolet absorber can be suppressed. In addition, since the ultraviolet absorber is incorporated into the crosslinked structure by the crosslinking reaction, the bleed out from the hard coat layer can be suppressed, and the decrease in the adhesion to the substrate can be suppressed. In particular, in the case of using the coating composition of the present invention using an ultraviolet ray absorber having an energy ray-curable functional group in a high temperature and high humidity environment, the effect of suppressing the decrease in the adhesion to a substrate is remarkably recognized.

  As such an energy ray-curable functional group-containing ultraviolet absorber, benzotriazole-based and triazine-based ultraviolet absorbers can be used. Examples of the benzotriazole-based UV absorber (compound) include 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, 2- (2′-hydroxy-5′-t-butylphenyl) benzotriazole, 2- (2'-hydroxy-3'-t-butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3 ', 5'-di-t-butylphenyl)- 5-chlorobenzotriazole, 2- (2'-hydroxy-3'-t-butyl-5 '-(2- (octyloxycarbonyl) ethyl) phenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy) -3'-Dodecyl-5'-methylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3 ', 5'-di-t-amylpheny ) Benzotriazole, 2- (2′-hydroxy-5′-t-octylphenyl) benzotriazole, 2- (2′-hydroxy-3 ′, 5′-di- (dimethylbenzyl) phenyl) benzotriazole, 2- (2′-hydroxy-4′-octyloxyphenyl) benzotriazole, 2,2′-methylene-bis (2- (2′-hydroxy-5′-t-octylphenyl) benzotriazole) 2- (2′- Examples thereof include hydroxy-3 '-(3,4,5,6-tetrahydrophthalimidylmethyl) -5'-methylbenzyl) phenyl) benzotriazole and the like and compounds having a (meth) acryloyl group. Moreover, as a triazine series ultraviolet absorber (compound), 2- (4-hexyloxy 2-hydroxyphenyl) -4,6-diphenyl-1,3,5-triazine, 2- (4-octyloxy-2-hydroxy) Phenyl) -4,6-di (2,5-dimethylphenyl) -1,3,5-triazine, 2- (4-butoxy-2-hydroxyphenyl) -4,6-di (4-butoxyphenyl)- 1,3,5-triazine, 2- (4-butoxy-2-hydroxyphenyl) -4,6-di (2,4-dibutoxyphenyl) -1,3,5-triazine, 2- (4- (4- (4 3- (2-ethylhexyloxy) -2-hydroxypropoxy) -2-hydroxyphenyl) -4,6-di (2,4-dimethylphenyl) -1,3,5-triazine, 2- (4- (4- (2-ethylphenyl)) 3-dodecyloxy 2-hydroxypropoxy) -2-hydroxyphenyl) -4,6-di (2,4-dimethylphenyl) -1,3,5-triazine, 2,4-di (4-butoxy-2-hydroxyphenyl)- 6- (4-Butoxyphenyl) -1,3,5-triazine, 2,4-di (4-butoxy-2-hydroxyphenyl) -6- (2,4-dibutoxyphenyl) -1,3,5 -Triazine etc. and the compound etc. which have a (meth) acryloyl group can be mentioned. Among them, a UV absorber having a maximum absorbance of 0.6 or more in the wavelength range of 280 nm to 370 nm of a 0.0619 mmol / l solution dissolved in dichloromethane is preferable in that it has excellent UV absorption performance. As such an ultraviolet absorber, a compound having 2- (2'-hydroxy-5'-methylphenyl) benzotriazole and a (meth) acryloyl group, and 2- (4-hexyloxy 2-hydroxyphenyl) -4 A compound having 6,6-diphenyl-1,3,5-triazine and a (meth) acryloyl group is preferably used. The energy ray-curable functional group-containing ultraviolet absorber as described above may be used alone or in combination of two or more.

  Although the addition amount of the component (B) varies depending on the desired weather resistance performance and the thickness of the hard coat layer, it is 2 as a lower limit with respect to a total of 100 parts by mass of the component (A) and component (C) described later. It is preferable to set the content to at least parts by mass, preferably at least 2.5 parts by mass, and more preferably at least 3 parts by mass. The upper limit is preferably 12 parts by mass or less, more preferably 10 parts by mass or less, and still more preferably 8 parts by mass or less. By setting the lower limit to 2 parts by mass or more, more excellent weather resistance can be obtained, and by setting the upper limit to 12 parts by mass or less, excellent coating film hardness, scratch resistance and substrate adhesion are maintained. Can.

(C) (Meth) acrylate oligomer (energy ray curable oligomer)
The coating composition of the present invention contains an energy ray curable oligomer having a weight average molecular weight of 1,500 or more and 20,000 or less. From the coating composition containing the above-mentioned oligomer, a hard coat layer and a hard coat film having good coating hardness and scratch resistance can be obtained.

By setting the weight average molecular weight of the energy ray curable oligomer to 1,500 or more, a hard coat film and a hard coat film having good flexibility and adhesion to a substrate can be obtained. In addition, by setting the weight average molecular weight of the energy ray curable oligomer to 20000 or less, preferably 10000 or less, a hard coat film or a hard coat film having good coating film hardness and scratch resistance can be obtained.
Here, the weight average molecular weight of the energy ray curable oligomer is preferably 1.5 to 20 times the weight average molecular weight of the energy ray curable monomer ((meth) acrylate monomer). By setting the ratio of the weight-average molecular weight of the energy ray-curable oligomer to the weight-average molecular weight of the energy ray-curable monomer in the above range, the energy ray-curable monomer can easily enter the gaps between the energy ray-curable oligomers. When the crosslinking reaction proceeds in a dense state and the crosslinking density increases, it is possible to effectively suppress the decrease in hardness and scratch resistance resulting from the addition of the ultraviolet absorber. Here, the weight average molecular weight of the energy ray curable monomer and the energy ray curable oligomer is a value determined by gel permeation chromatography (GPC).

  As the energy ray curable oligomer, a (meth) acrylic oligomer having a two or more (meth) acryloyl group in one molecule and having a three-dimensional network structure by crosslinking and curing is particularly preferably used. Examples of such (meth) acrylic oligomers include urethane (meth) acrylate, polyester (meth) acrylate, epoxy (meth) acrylate, melamine (meth) acrylate, polyfluoroalkyl acrylate, silicone acrylate and the like.

  The energy ray-curable oligomer is preferably a polyfunctional urethane (meth) acrylate oligomer having an energy ray-curable functional group number of 10 or more and 20 or less. By using such a polyfunctional urethane (meth) acrylate oligomer, a high crosslinking density can be achieved, and therefore, the coating film hardness and the scratch resistance can be further improved. By setting the number of energy ray-curable functional groups of the polyfunctional urethane (meth) acrylate oligomer to 10 or more, the crosslink density can be sufficiently increased to increase the hardness. And as a result, abrasion resistance can be improved significantly. Further, by setting the number of energy ray-curable functional groups to 20 or less, preferably 16 or less, steric hindrance due to high crosslinking density can be suppressed, and a decrease in hardness due to curing inhibition can be prevented.

  The content ratio of the component (A) (energy ray curable monomer) to the component (C) (energy ray curable oligomer) in the coating composition of the present invention is preferably 3:97 to 50:50 by mass ratio. And preferably 5:95 to 30:70. By setting the mass ratio of the component (A) to the component (C) in the coating composition in the above range, the substrate adhesion between the hard coat layer and the transparent support, in particular the substrate adhesion after the moisture resistance test, can be made more It can be good.

(D) Light Stabilizer The coating composition of the present invention preferably contains a hindered amine light stabilizer as the (D) light stabilizer. By adding a hindered amine light stabilizer to the hard coat layer, it is possible to efficiently capture radicals generated by ultraviolet light, and therefore the weatherability can be further improved. (D) As a light stabilizer, for example, 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, 4-hexanoyloxy-2,2,6,6-tetramethylpiperidine, 4-octanoyloxy -2,2,6,6-Tetramethylpiperidine, 4-Stearoyloxy-2,2,6,6-Tetramethylpiperidine, Succinic Acid-Bis (2,2,6,6-Tetramethylpiperidine), Sabanic Acid Bis (2,2,6,6-tetramethylpiperidine), Sabanic acid bis (1,2,2,6,6-pentamethyl-4-piperidine), 8-acetyl-3-dodecyl-7,7, 9,9-Tetramethyl-1,3,8-triazaspiro [4,5] decane-2,4-dione, N-methyl-3-dodecyl-1- (2,2,6,6-tetramethyl-4 -Piperini ) Pyrrolidine-2,5-dione, N-acetyl-3-dodecyl-1- (2,2,6,6-tetramethyl-4-piperidinyl) pyrrolidine-2,5-dione, phthalic acid-bis (1,1 2,2,6,6-pentamethyl-4-piperidine), trimesic acid-tris (2,2,6,6-tetramethyl-4-piperidyl) and the like. These may be used singly or in combination of two or more.

  The addition amount of the component (D) is preferably 0.05 parts by mass or more, more preferably 0.5 parts by mass or more, as a lower limit with respect to a total of 100 parts by mass of the components (A) and (C) described above. 5 parts by mass or less, and further preferably 3 parts by mass or less. Favorable weather resistance is obtained by the addition amount of (D) component being 0.05 mass part or more, and favorable abrasion resistance can be maintained by setting it as 5 mass parts or less.

(E) Photoinitiator The (E) photoinitiator used in the coating composition of the present invention is (E1) in a wavelength range of 340 nm to 400 nm of a 0.01% by mass solution dissolved in methanol or acetonitrile. The photopolymerization initiator having a maximum absorbance of 0.1 or more, and (E2) a 0.001 mass% solution dissolved in methanol or acetonitrile has a maximum absorbance of 0.1 or more in a wavelength range of 220 nm to 280 nm It is preferable to contain one or more types of photopolymerization initiators. When forming a cured coating film by ultraviolet irradiation, by using these two types of photopolymerization initiators, the decrease in substrate adhesion in a high temperature and high humidity environment is largely suppressed as compared with the case where each is used alone. be able to.

[(E1) component]
The component (E1) used in the present invention is a photopolymerization initiator having a maximum absorbance of 0.1 or more in a wavelength range of 340 nm to 400 nm of a 0.01% by mass solution dissolved in methanol or acetonitrile. . For example, 1-hydroxy-cyclohexyl-phenyl-ketone, 2,2-dimethoxy-1,2-diphenylethan-1-one, bis (2,4,6-trimethylbenzoyl) -phenyl phosphine oxide, 2-benzyl- 2-Dimethylamino-1- (4-morpholinophenyl) -butanone-1, bis (η5-2,4-cyclopentadien-1-yl) -bis (2,6-difluoro-3- (1H-pyrrole) 1-yl) -phenyl) titanium, 2-dimethylamino-2- (4-methylbenzyl) -1- (4-morpholinophenyl) butanone, diphenyl (2,4,6-trimethyl benzoyl) phosphine oxide, etc. be able to. The said component may be used individually by 1 type, and may use 2 or more types together.

  A commercial item can be used for (E1) component, For example, Irgacure 651, 907, 819, 369, 379, 1800, 784, Darocure 4265, Lucirin TPO (above, BASF Corporation make) etc. can be mentioned.

[(E2) component]
The component (E2) used in the present invention is a photopolymerization initiator having a maximum absorbance of 0.1 or more in a wavelength range of 220 nm to 280 nm of a 0.001% by mass solution dissolved in methanol or acetonitrile. . For example, 2-methyl-1 [4- (methylthio) phenyl] -2-morpholinopropan-1-one 2,2-dimethoxy-1,2-diphenylethane-1-one, 1- [4- (2) -Hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, methyl oxophenyl acetate, oligo [2 And -hydroxy-2-methyl- [1- (4-methylvinyl) phenyl] propanone etc. can be mentioned. The said component may be used individually by 1 type, and may use 2 or more types together.

  As the component (E2), commercially available products can be used. For example, Irgacure 184, 651, 500, 2959, 127, 754, 907, 1800, Darochure 1173, MBF (above, manufactured by BASF Corp.), Isacure KIP150, KIP100F, ONE (Above, made by Lamberti) can be mentioned.

From the viewpoint of suppressing the decrease in the adhesion of the substrate in a high temperature and high humidity environment, the addition amount of the photopolymerization initiator which is the component (E1) is made smaller than the addition amount of the photopolymerization initiator which is the component (E2) Is preferred. It is preferable that the addition ratio of (E1) component and (E2) component is the range of 3: 97-45: 55 by mass ratio specifically ,. In addition, when it contains several (E1) component and / or (E2) components, it is preferable that ratio of the gross mass of each of (E1) component and (E2) component becomes said range.
Further, there are some photopolymerization initiators which have a photopolymerization initiation wavelength region of the (E1) component and the (E2) component in one kind. In addition, hereinafter, the maximum value of the absorbance of such a photopolymerization initiator in a wavelength range of 340 nm to 400 nm of a 0.01% by mass methanol solution or acetonitrile solution is 0.1 or more and 0.001% by mass A photopolymerization initiator having a maximum absorbance of 0.1 or more in a wavelength range of 220 nm to 280 nm of the methanol solution or the acetonitrile solution is referred to as a component (E1, 2) or a photoinitiator (E1, 2). However, even if one kind of (E1, 2) photopolymerization initiator is used, the effect as obtained by using two kinds of the (E1) photopolymerization initiator and the (E2) photopolymerization initiator together can not be obtained. . On the other hand, when two or more kinds of (E1, 2) photopolymerization initiators are used, the same effect as when using the (E1) photopolymerization initiator and the (E2) photopolymerization initiator in combination is observed. . The same effect can be obtained also when the photopolymerization initiator of (E1) or the photopolymerization initiator of (E2) is further added to the photopolymerization initiator of (E1, 2). In this case, particularly, by adding the component (E2), more excellent effects can be obtained. From the viewpoint of production, the type and amount of the polymerization initiator as the additive are preferably as small as possible. However, the photopolymerization initiator of (E1) and the photopolymerization initiator of (E1) and the photopolymerization of (E2) can be added to the photopolymerization initiator of (E1,2) as long as the physical properties of the hard coat layer or the hard coat film are not affected. An initiator can also be added.
In the present application, “containing the (E1) component and the (E2) component” ”includes a constitution containing two or more kinds of the photopolymerization initiators of (E1, 2) and a photopolymerization initiator of (E1, 2) The composition containing the photopolymerization initiator E1) and / or the photopolymerization initiator (E2) is also included.
As described above, by containing two types of photopolymerization initiators, the scratch resistance which was the problem of the hard coat film and the hard coat film obtained from the conventional energy ray-curable coating composition having the ultraviolet ray absorbing performance And substrate adhesion can be improved. In particular, by using the two types of photopolymerization initiators, it is possible to obtain a coating film in which the substrate adhesion in a high temperature and high humidity environment is significantly improved.

  The content of the component (E) used in the hard coat paint of the present invention is 1 part by mass, and further 3 parts by mass as a lower limit with respect to a total of 100 parts by mass of the components (A) and (C). The upper limit thereof is preferably 15 parts by mass or less, and more preferably 12 parts by mass or less. By setting the amount to 1 part by mass or more, the coating film hardness and the adhesion to the substrate can be made sufficient, and by setting the amount to 15 parts by mass or less, inhibition of curing due to recombination of the components (E) is prevented. The adhesion to a substrate can be made sufficient.

  Furthermore, in the coating composition of the present invention, as necessary, other resins, solvents, photopolymerization initiation assistants, leveling agents, antifoaming agents, antioxidants, polymerization inhibitors, crosslinking agents, pigments, antifouling agents Additives such as additives, fine particles, lubricants, fluorescent whitening agents, antistatic agents, flame retardants, antibacterial agents, antifungal agents, plasticizers, flow control agents, dispersants, release agents, etc. It is also possible to provide a function that

  Other resins include, for example, thermosetting resins, thermoplastic resins, epoxy resins such as bisphenol epoxy resins, novolac epoxy resins, alicyclic epoxy resins, aliphatic epoxy resins, and cationic photopolymerization such as vinyl ether resins. Resin etc. can be mentioned, and it can be contained in the range which does not inhibit the effect of this invention.

  As the solvent, aromatic solvents such as toluene and xylene; ester solvents such as ethyl acetate, butyl acetate, methoxybutyl acetate and methoxypropyl acetate; ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; diethyl ether, Ether solvents such as dibutyl ether, tetrahydrofuran, 1,3-dioxolane, 1,4-dioxane, propylene glycol monomethyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol ethyl methyl ether and the like: Other known organic solvents can be mentioned.

  The type of organic solvent to be used is determined in consideration of the solubility or dispersibility with the components (A), (B), (C) and the like added simultaneously. An organic solvent having a boiling point of 120 ° C. or less such as methyl ethyl ketone, methyl isobutyl ketone and tetrahydrofuran is preferable in that the solvent hardly remains in the hard coat layer after drying. The organic solvents may be used alone or in combination of two or more. The amount of the solvent used is not particularly limited, but it is preferable to adjust the viscosity of the composition to be a viscosity suitable for the coating method to be employed. The preferred amount to be used is 5 to 90% by mass, more preferably 10 to 85% by mass, and still more preferably 20 to 80% by mass of the whole composition.

  As a photopolymerization start adjuvant, an amine compound, a carboxylic acid compound, a polyfunctional thiol compound etc. can be mentioned, for example. Moreover, an acrylic compound, a high boiling point solvent, a fluorine compound, a silicone compound etc. can be mentioned as a leveling agent. Among the above leveling agents, fluorine compounds and silicone compounds are preferable from the viewpoint of finishing the surface to a mirror surface. Examples of the antioxidant include phenolic compounds. Examples of the polymerization inhibitor include methoquinone, methyl hydroquinone, hydroquinone and the like. As a crosslinking agent, isocyanates, a melamine compound, etc. can be mentioned. Examples of the fine particles include inorganic fine particles such as silica and calcium carbonate, and organic fine particles such as polymethyl methacrylate and polystyrene. The antifouling agent may be a fluorine-based compound, a silicon-based compound, or a mixture thereof, and a fluorine-based compound is preferable in terms of antifouling performance.

  The coating composition of the present invention comprises the components (A), (B), and (C), and, if necessary, the addition of other resins, solvents, light stabilizers, photopolymerization initiators, etc. It can be obtained by adding and mixing the agents in any order.

  The coating composition of the present invention thus obtained is a coating composition (hard coat paint) for applying and curing on the surface of a glass or resin material. Since the hard coat paint of the present invention contains the components (A), (B) and (C) described above, when the glass and resin material are used as the article to be coated, the article and the cured product Adhesion to the coating film is good. In particular, in a high temperature and high humidity environment, a cured coating film excellent in the adhesion (substrate adhesion) between the object to be coated and the cured coating film can be obtained.

(2) Hard Coat Film and Hard Coat Film The hard coat film of the present invention comprises the solvents (A), (B) and (C), and, if necessary, other resins and additives as solvents. The coating composition (the composition for the hard coat layer) dissolved or dispersed therein is applied to at least one surface of the transparent support, and if necessary, dried and cured by irradiation with energy rays or natural light. be able to. For coating, known methods such as gravure coating, bar coating, knife coating, roll coating, blade coating, die coating, spin coating, flow coating, dip coating, spray coating, screen printing Law, brushing, etc. can be used. If the viscosity of the composition for hard coat layer is higher than the viscosity suitable for coating, the viscosity may be adjusted using a solvent. The solvents that can be used are as described above.

  As the transparent support, those having high transparency such as glass and resin base can be used. The type of resin constituting the resin base includes, for example, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyethylene, polypropylene, cellophane, diacetyl cellulose, triacetyl cellulose, acetyl cellulose butyrate, polyvinyl chloride, polyvinylidene chloride, Polyvinyl alcohol, ethylene-vinyl acetate copolymer, polystyrene, polycarbonate, polymethylpentene, polysulfone, polyetheretherketone, polyethersulfone, polyetherimide, polyimide, fluorine resin, nylon, acrylic, cycloolefin, norbornene compound, etc. You can raise it. Among the above, a polyethylene terephthalate film stretched, particularly biaxially stretched, is preferably used because it is excellent in mechanical strength and dimensional stability.

  Such a transparent support is intended to improve the adhesion to the hard coat layer, and the surface is roughened by sandblasting, solvent treatment, etc., or corona discharge treatment, chromic acid treatment, flame treatment, hot air treatment, plasma Treatment, surface treatment such as ozone / ultraviolet radiation treatment, formation of an undercoat easily adhesion layer, etc. may be performed. Moreover, before apply | coating the composition for hard-coat layers to the transparent support body, the printing and coating for the adhesive layer and design property provision may be previously provided to one or both surfaces. In addition, the transparent support may contain an additive that can be used in the above-described coating composition, such as an ultraviolet absorber and a light stabilizer, as long as the effects of the present invention are not impaired.

  The thickness of the transparent support is not particularly limited and may be appropriately selected according to the application. In the case of glass, 0.3 mm to 5 mm is preferable, and in the case of a resin base material, 25 μm to 500 μm is preferable, and 50 μm to 300 μm is more preferable.

  In the case of containing a solvent in the composition for hard coat layer, it is necessary to carry out drying after application. The drying temperature may be determined in consideration of the length of the drying line, the line speed, the coating amount, the residual solvent amount, the type of the transparent support, and the like. If the transparent support is a polyethylene terephthalate film, the general drying temperature is 50 ° C to 150 ° C, preferably 70 ° C to 130 ° C. When there are a plurality of dryers in one line, each dryer may be set to a different temperature and wind speed. In order to obtain a coating having a good coating appearance, it is preferable to make the drying conditions on the inlet side mild.

As a method of curing the composition for hard coat layer, as described above, it can be cured by irradiation of energy rays or natural light. In consideration of stability of physical property values of the hard coat layer and industrial workability, it is preferable to cure by irradiation of energy ray. Examples of energy rays include ultraviolet rays and electron beams. In the case of curing by ultraviolet light, an ultraviolet irradiation device having a xenon lamp, a high pressure mercury lamp, a metal halide lamp or the like as a light source is used, and the light amount, the arrangement of the light source, etc. are adjusted as needed. When using a high pressure mercury lamp preferably cured at a transport speed 5 m / min ～60M / min for one lamp having an energy of ^{80W / cm 2 ~160W / cm 2} . In the case of curing by electron beam, it is preferable to use an electron beam accelerator having an energy of 100 eV to 500 eV.

  The thickness of the hard coat layer is not particularly limited, and may be appropriately determined depending on the use application, required performance, handleability, productivity and economy. When used in mobile products, the thickness is preferably 0.5 μm or more, more preferably 1 μm or more as the lower limit, and 20 μm or less, further preferably 15 μm or less, further preferably 10 μm or less as the upper limit. By setting the thickness of the hard coat layer to 0.5 μm or more, necessary coating film hardness, scratch resistance, weather resistance, and substrate adhesion can be obtained. By setting the thickness of the hard coat layer to 20 μm or less, a decrease in productivity and economy can be suppressed.

  The hard coat layer of the hard coat film of the present invention preferably has a pencil hardness as defined in JIS K5400 adjusted to 2H or more, and more preferably 3H or more. In the coating film in which the pencil hardness is adjusted to the above value or more, the surface of the hard coat layer can be effectively prevented from being damaged.

The hardcoat layer of the hardcoat film of the present invention is a product obtained by winding # 0000 steel wool on a 3 cm ² cylindrical jig and winding it with a load of 500 g 30 times or more, preferably 50 times or more, more preferably Is preferably adjusted so as not to cause scratches when reciprocated 70 times or more. By adjusting in this manner, necessary scratch resistance can be secured, and the surface of the hard coat layer can be effectively prevented from being scratched.

  Moreover, it is preferable that the base-material adhesiveness based on JISK5400 of a hard-coat layer and a transparent support body of the hard coat film of this invention is 90/100 or more. By setting the substrate adhesion to the above range, when used in a mobile product, the hard coat layer can be used without being peeled off from the transparent support.

  Furthermore, the hard coat film of the present invention has a temperature of 60 ° C. and a relative humidity of 90%. H. It is preferable that the base-material adhesiveness based on JISK5400 of the hard-coat layer after a moisture resistance test left to stand in the environment of 550 hours and a transparent support is 90/100 or more. By setting the substrate adhesion after the moisture resistance test to the above range, it is possible to obtain a hard coat film in which the substrate adhesion between the hard coat layer and the transparent support is maintained even after the moisture resistance test. Furthermore, even in consideration of the environment during transportation of the hard coat film of the present invention and the long-term storage stability of the mobile product, the hard coat layer can be used without deterioration in a high temperature and high humidity environment. Moreover, it is preferable to have abrasion resistance in the same steel wool test as above also after the said moisture resistance test.

  The hard coat film of the present invention preferably has a yellowing degree (Δb) of less than 1.0, more preferably less than 0.5, after 12 cycles of weathering test specified in ASTM G-154. By setting the degree of yellowing (Δb) in the above range, it is possible to obtain a hardcoat film which is less likely to yellow and which has low coating deterioration even when used in a mobile product used outdoors. In the present invention, the yellowing degree (Δb) indicates a value obtained by subtracting the b value (b0) before the test from the b value (b1) after the weather resistance test. Therefore, the smaller the value is, the lower the coating deterioration is.

  As described above, as one embodiment of the hard coat film of the present invention, the one having the hard coat layer on one side of the transparent support has been described. The present invention is not limited to the above constitution, and one having a hard coat layer on both sides of a transparent support, and one having a pressure sensitive adhesive layer and printing on the side having no hard coat layer on a transparent support. A layer and those having a deposited layer are also included.

  The hard coat film of the present invention as described above does not cause yellowing because it has sufficient weather resistance even when used on a display screen of a mobile product used outdoors, a mobile product such as a smartphone. Further, since the adhesion to a substrate is excellent, it can be used without peeling between the hard coat layer and the transparent support. In particular, in the hard coat film of the present invention, the hard coat layer does not deteriorate in a high temperature and high humidity environment, and the substrate adhesion is excellent also in such an environment. Therefore, for example, even when the production base of each component of the mobile product and the assembly base of the mobile product are different, it can be used under the environment of high temperature and high humidity at the time of manufacturing and transportation of various components. In particular, in order to cope with higher weathering levels in recent years, a large amount of UV absorbers and light stabilizers tend to be added to the hard coat layer, which causes various problems. The present invention technology is useful as a hard coat film having.

  EXAMPLES Hereinafter, the present invention will be specifically described based on examples, but the present invention is not limited to these examples.

<Components of Coating Composition>
Details of each component used in the following examples and comparative examples are shown below.
(A) (meth) acrylate monomer (energy ray curable monomer)
A1: dipentaerythritol hexaacrylate monomer (trade name: light acrylate DPE-6A, manufactured by Kyoeisha Chemical Co., Ltd., energy ray curable functional group number: 6, hydroxyl number: 0, weight average molecular weight 563, energy ray curable functional group number (E ): 6)

  A2: Dipentaerythritol triacrylate monomer (trade name: Light acrylate PE-3A, manufactured by Kyoeisha Chemical Co., Ltd., energy ray curable functional group number (E): 3, hydroxyl group number: 1, weight average molecular weight 298)

  A'1: epoxy acrylate monomer (trade name: epoxy ester 200PA, manufactured by Kyoeisha Chemical Co., Ltd., energy ray curable functional group number (E): 2, number of hydroxyl groups: 2, weight average molecular weight 332)

  A'2: 2-hydroxy-3-acryloyloxypropyl methacrylate monomer (trade name: NK ester 701A, manufactured by Shin-Nakamura Chemical Co., Ltd., energy ray curable functional group number (E): 2, hydroxyl group number: 1, weight average Molecular weight 214)

A'3: polyethylene glycol # 1000 diacrylate monomer (trade name: NK ester A-1000, Shin-Nakamura Chemical Co., Ltd., energy ray curable functional group number (E): 2, hydroxyl group number: 0, weight average molecular weight 1108)
A'4: Methoxy polyethylene glycol # 400 acrylate monomer (trade name: NK ester AM-90G, Shin-Nakamura Chemical Co., Ltd., energy ray curable functional group number (E): 1, hydroxyl group number: 0, weight average molecular weight 454)

(B) UV absorber B: energy ray-curable benzotriazole type UV absorber (trade name: RUVA-93, manufactured by Otsuka Chemical Co., Ltd., in a wavelength range of 280 nm to 370 nm in a solution of 0.0619 mmol / l dissolved in dichloromethane Maximum absorbance value is 0.6 or more)

  B'1: Benzotriazole-based ultraviolet absorber that is not energy ray curable (trade name: Tinuvin 928, manufactured by BASF)

  B'2: Non-energy ray curable benzophenone-based ultraviolet absorber (trade name: LS-907, manufactured by Izumisha Yushi Kogyo Co., Ltd.)

(C) (Meth) acrylate oligomer (energy ray curable oligomer)
C1: Aliphatic urethane acrylate oligomer (trade name: Art resin UN-904, manufactured by Negami Chemical Industries, energy ray curable functional group number: 10, weight average molecular weight 4900)

  C2: Aliphatic urethane acrylate oligomer (trade name: Art resin UN-3320HS, manufactured by Negami Co., Ltd., energy ray curable functional group number: 15, weight average molecular weight 4900)

(D) Light stabilizer (D) Component: hindered amine light stabilizer (trade name: Tinuvin 765, manufactured by BASF)

(E) Photopolymerization initiator E1-1: Bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide (trade name: Irgacure 819, manufactured by BASF)
E1-1: 2-dimethylamino-2- (4-methyl-benzyl) -1- (4-morpholine-4-yl-phenyl) -butan-1-one (trade name: Irgacure 379, manufactured by BASF)

E2: 2-Methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one (trade name: Irgacure 907, manufactured by BASF)
E1,2: 2,2-Dimethoxy-1,2-diphenylethane-1-one (trade name: Irgacure 651, manufactured by BASF)

1. Preparation of Coating Composition and Hard Coat Film (A) (Meth) Acrylate Monomer Shown in Tables 1 to 5, (B) UV Absorber, and (C) (Meth) Acrylate Oligomer Solid Content shown in Tables 1 to 5 It weighed by ratio (mass part). The details of each component are as described above. Furthermore, (D) 1 part by mass of a light stabilizer, (E) (E-1) bis (2,4,6-trimethyl benzoyl) -phenyl phosphine oxide as a photopolymerization initiator (trade name: Irgacure 819, BASF AG) 3) and (E-2) 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one (trade name: Irgacure 907, manufactured by BASF Corp.) at 3 wt. 4 parts by mass were added. In addition, about Example 4 to Example 14 shown in Table 2, the photoinitiator described in Table 2 was added by the mass ratio shown in Table 2. The above components were mixed with 75 parts by mass of methyl ethyl ketone (MEK) and 75 parts by mass of propylene glycol monomethyl ether (PGM), respectively, and stirred to obtain coating compositions (solid content 43%) of Examples and Comparative Examples. Next, as a transparent support, the coating compositions of Examples and Comparative Examples are applied by a bar coat method to one side of a 188 μm thick polyethylene terephthalate film (trade name: Cosmo Shine A4300, manufactured by Toyobo Co., Ltd.). After drying for 2 minutes, a high pressure mercury lamp was irradiated and cured at 300 mJ / cm ² to form a hard coat layer having a thickness of 6 μm, thereby obtaining hard coat films of Examples and Comparative Examples.

2. Evaluation The hard coat film of the obtained Example and Comparative Example was measured or evaluated by the following method about four items, coating film hardness (pencil hardness), abrasion resistance, weather resistance, and substrate adhesion. The results of Examples 1 to 3 and Comparative Examples 1 to 7 are shown in Table 1, and the results of Examples 4 to 14 are shown in Table 2. Reference Example 15 , Examples 16 to 17, Reference Example The results of 18 are shown in Table 3, the results of Examples 19 to 22 are shown in Table 4, and the results of Example 23 to 25 are shown in Table 5.

[Film hardness]
According to JIS K5400, the pencil hardness of the hard coat film of the example and the comparative example was measured using a pencil scratching tester. Specifically, with the hardcoat film hard coat layer facing up, set the pencil at a 45 degree angle, scratch 5 mm with a load of 1000 g from the top, and not scratched more than 4 times in 5 times Was recorded.

[Scratch resistance]
<Early scratch resistance>
As a steel wool resistance test, what rolled # 0000 steel wool on 3 cm ² cylindrical jig | tool was wound on the hard-coat layer of the hard-coat film of an Example and a comparative example, and it was made to reciprocate by load 500g. The number of times immediately before the scratch first occurred was recorded as the initial evaluation value of scratch resistance.
<Scratch resistance after moisture resistance test>
It measures in the same manner as the initial steel wool resistance test using the hard coat film of the example and comparative example after a moisture resistance test which will be described later, and the number of times immediately before the scratch first occurs is the abrasion resistance after the moisture resistance test It was recorded as a sex evaluation value.

[Weatherability (Δb)]
As a weather resistance test, according to ASTM G-154, using a QUV ultraviolet fluorescence accelerator (manufactured by Q-LAB), the hard coat film of the example and the comparative example is subjected to an UVA 340 lamp for 8 hours at 60C. After irradiation with ultraviolet light, the resultant was left in a dark room under a dew condensation environment at room temperature of 50.degree. C. for 4 hours to condense each hard coat film. This was performed 12 cycles as one cycle. The yellowing factor (Δb) after 12 cycles was measured using a spectrocolorimeter (trade name: CM-5, manufactured by Konica Minolta Sensing, Inc.), and recorded as a weather resistance evaluation value.

[Base material adhesion]
<Basic adhesion to substrate>
As a substrate adhesion test, in the hard coat layers of the hard coat films of Examples and Comparative Examples, nicks are made so that 100 squares with a gap of 1 mm can be formed according to the cross-cut tape method of JIS K5400, JIS Z1522 After sticking and peeling the cellophane adhesive tape defined in, the number of the coating films remaining on the transparent support was visually counted and recorded as an initial evaluation value of the substrate adhesion.

<Adhesion to substrate after weathering test>
Using the hard coat film after the weathering test, it was measured in the same manner as in the initial substrate adhesion test, and was recorded as an evaluation value of the substrate adhesion after the weathering test.

<Adhesiveness to substrate after moisture resistance test>
As a moisture resistance test, temperature 60 ° C., relative humidity 90% R.H. H. The sample was allowed to stand for 550 hours in the following environment, measured in the same manner as the initial substrate adhesion test, and recorded as an evaluation value of the substrate adhesion after the moisture resistance test.

Table 1 shows the results of evaluation of various properties of the hard coat films of Examples 1 to 3 and Comparative Examples 1 to 7.
The hard coat film obtained from the coating composition of Comparative Example 1 which does not contain an oligomer component and uses a high-hardness monomer (A2) having three energy ray-curable functional groups has good hardness and scratch resistance. I understood it. However, in the coating composition of Comparative Example 1, the cure shrinkage was large, and a large warpage occurred in the hard coat layer. Further, the hard coat film of Comparative Example 1 had low initial adhesion to a substrate, and a further significant decrease was observed after the weathering test and after the moisture resistance test, and it was confirmed that it was not suitable for practical use. In Comparative Example 1, the curing shrinkage is considered to be large because it does not have an oligomer. The same curing shrinkage was observed when A1 was used instead of A2. Moreover, in the hard coat film of Comparative Example 1, it was confirmed that the weather resistance is not sufficient. Although the number of hydroxyl groups of A2 is 1, in Comparative Example 1, since the amount of hydroxyl groups in the entire coating composition is large because no oligomer is contained, it is considered that unreacted hydroxyl groups remain even after curing. Be
Although not described in the table, in the case of a hard coat film obtained from a coating composition containing 100 parts by mass of C1, which is an oligomer component, containing no monomer component, the pencil hardness and the scratch resistance are good. It was confirmed that sufficient adhesion with the substrate was not obtained.
On the other hand, in Example 1 containing monomer component A1 and oligomer component C1, Example 2 containing monomer component A2 and oligomer component C1, and Example 3 containing monomer component A1 and oligomer component C2, It was found that a hard coat film excellent in coating film hardness, scratch resistance, weather resistance and substrate adhesion was obtained.

On the other hand, from the coating composition of Comparative Example 2 containing monomer component A'1 (weight-average molecular weight: 332, hydroxyl group: two, energy ray curable functional group number 2) and oligomer component C1 (mass-average molecular weight: 4900) In the obtained hard coat film, hardness and abrasion resistance fell compared with Examples 1-3. Furthermore, it was also confirmed that the weatherability was lowered and yellowed after irradiation with ultraviolet light, and the adhesion to the substrate was lowered after the weathering test and the moisture resistance test. Since A'1 has two hydroxyl groups, the decrease in the above properties is considered to be the influence of the remaining hydroxyl group and / or the water adsorbed to the remaining hydroxyl group.
Obtained from the coating composition of Comparative Example 3 containing monomer component A'2 (weight average molecular weight: 214, hydroxyl group: 1 and energy ray curable functional group number 2) and oligomer component C1 (weight average molecular weight: 4900) The hardness and the abrasion resistance of the hard coat film were lower than those of Examples 1 to 3. This is considered to be due to the fact that the weight average molecular weight of A'2 is as low as 214. Furthermore, in the hard coat film of Comparative Example 3, it was also confirmed that the weatherability was lowered and yellowed after irradiation with ultraviolet light, and the adhesion to the substrate was lowered after the weathering test and the moisture resistance test. Although the number of hydroxyl groups in A'2 is one, the number of hydroxyl groups occupied in the whole coating composition is large because the molecular weight is small, and excess hydroxyl groups remain even after curing, so adsorption onto residual hydroxyl groups and / or residual hydroxyl groups It is thought that such deterioration of characteristics occurs due to the influence of water.

Obtained from the coating composition of Comparative Example 4 containing monomer component A'3 (weight average molecular weight: 1108, hydroxyl group: 0, energy beam curable functional group number 2) and oligomer component C1 (weight average molecular weight: 4900) The hardness and the abrasion resistance of the hard coat film were lower than those of Examples 1 to 3. It is considered that this is because the weight-average molecular weight of A'3 is as large as 1108 and the monomer component A'3 can not enter into the interstices of the oligomer component and the crosslink density does not increase. Furthermore, in the hard coat film of Comparative Example 4, it was also confirmed that the adhesion to the substrate was reduced after the weathering test and the moisture resistance test. In Comparative Example 4, since the molecular weight of the monomer component is large, the crosslink density is not improved, and therefore, it is difficult to form a bond with the surface of the substrate, and therefore peeling is likely to occur under the influence of ultraviolet irradiation or humidity.
Obtained from the coating composition of Comparative Example 5 containing monomer component A'4 (weight average molecular weight: 454, hydroxyl group: 0, energy beam curable functional group number 1) and oligomer component C1 (weight average molecular weight: 4900) Even in the case of the hard coat film, the hardness and the abrasion resistance were significantly reduced as compared with Examples 1 to 3. This is considered to be due to the fact that a sufficient crosslinking reaction does not proceed with one energy ray curable functional group of A'4. Furthermore, in the hard coat film of Comparative Example 5, it was also confirmed that the weatherability and the initial adhesion to the substrate were low, and the adhesion to the substrate was further reduced after the weathering test and after the moisture resistance test. As described above, in Comparative Example 5, since the number of energy ray-curable functional groups is small, a sufficient crosslinking reaction does not proceed, and the initial adhesion to the substrate is considered to be low. Moreover, since it is low crosslinking density, it is thought that it is easy to deteriorate in ultraviolet irradiation and a high humidity environment as a cause of the fall of the base material adhesiveness after a weather resistance and various tests.

In Comparative Examples 6 and 7 in which an ultraviolet ray absorber which is not energy ray curable is used instead of the energy ray curable ultraviolet ray absorber B1, Comparative Example 6 and 7 have lower hardness and scratch resistance as compared with the examples, and are weather resistant. It was found that the adhesion to the substrate was lowered after the property test and after the moisture resistance test.
From the above results, it contains (meth) acrylate monomer having a predetermined molecular weight, energy ray curable functional group number and hydroxyl group number, an energy ray curable oligomer having a predetermined molecular weight and an energy ray curable functional group-containing ultraviolet absorber It was found that the hard coat film obtained from the coating composition of the present invention provides excellent scratch resistance, weather resistance and substrate adhesion.

In Table 2, the base-material adhesiveness evaluation result of the hard coat film of Examples 4-14 is shown.
In Examples 4 to 14, the types and the compounding amounts of (A) (meth) acrylate monomer, (B) UV absorber, (C) acrylate oligomer and (D) light stabilizer are the same as in Example 1 ( E) The type and blending ratio of the photopolymerization agent are changed. In Example 4, 7 parts by mass of E1 alone is added as a photopolymerization agent, in Example 9 7 parts by mass of E2 alone is added, and in Examples 1 and 5 to 8, the compounding ratio of E1 to E2 is changed, It is added to be 7 parts by mass in total. Here, in Examples 1 and 5 to 8 containing E1 and E2 as compared with Examples 4 and 9 containing either E1 or E2, adhesion to a substrate after a weather resistance test and after a moisture resistance test Was found to improve. In particular, in Examples 1 and 5 to 6, the substrate adhesion after the moisture resistance test is significantly improved.
Moreover, in Example 10, two types of photoinitiator E1 whose maximum value of the absorbance in the wavelength range of 340 nm to 400 nm of a 0.01% by mass methanol solution or acetonitrile solution is 0.1 or more are added. As in the above-described example in which E2 and E2 are used in combination, the effect of largely suppressing the decrease in the substrate adhesion after the weather resistance test and the moisture resistance test was not observed. Furthermore, in Example 11, the maximum value of the absorbance in the wavelength range of 340 nm to 400 nm of a 0.01% by mass methanol solution or acetonitrile solution is at least 0.1 and 220 nm to 280 nm in a 0.001% by mass methanol solution One kind of photopolymerization initiator whose maximum value of absorbance in the wavelength range of 0.1 or more was added. However, as in the example in which E1 and E2 were used in combination, the effect of largely suppressing the decrease in the substrate adhesion after the weather resistance test and after the moisture resistance test was not obtained.
In Examples 12 to 14, the types of photoinitiators E1 and E2 and the ratio of the two (E1: E2 = 3: 4) are the same as in Example 1, and the total amount of photoinitiators E1 and E2 is I am changing the mass ratio. In Example 12, Example 1, Example 13 and Example 14, the mass ratio of the total amount of E1 and E2 is 3.5, 7, 10.5 and 14, respectively. In any of the examples, it was confirmed that excellent substrate adhesion was maintained after the weathering test and after the moisture resistance test.
From the above results, it was confirmed that using two types of photopolymerization agents having a predetermined absorbance in a predetermined wavelength range in combination is effective for improving the adhesion to a substrate.

Table 3 shows various evaluation results of the hard coat films of Reference Example 15 , Examples 16 to 17, and Reference Example 18.
In Examples 12 to 14 and Reference Example 15, (A) (meth) acrylate monomer, (B) UV absorber, (C) (meth) acrylate oligomer, (D) light stabilizer, (E) photopolymerization agent The compounding amounts of the type and (B) UV absorber, (D) light stabilizer, and (E) photopolymerization agent are the same as in Example 1, and (A) (meth) acrylate monomer and (C) (meth) acrylate The composition ratio of the oligomers is changed.
Here, since the high hardness monomer (A1) is used, the pencil hardness and the scratch resistance are improved as the amount of the monomer is increased. Moreover, it turned out that the outstanding weather resistance and base-material adhesiveness are obtained also in any Example. In particular, in Example 16, Example 1, and Example 17 in which the content ratio of the component (A) and the component (C) is in the range of 3:97 to 50:50 by mass ratio, the substrate adhesion after the moisture resistance test It has been confirmed that the sex is greatly improved.

Table 4 shows various evaluation results of the hard coat films of Examples 19 to 22.
In Example 19 and Example 22, except that the thickness of the hard coat layer was changed as shown in Table 4, a hard coat film was produced and evaluated in the same manner as in Example 1. It was confirmed that the scratch resistance was further improved by increasing the thickness of the hard coat layer to 3 μm, 6 μm and 15 μm. However, it was found that sufficient scratch resistance, substrate adhesion and weather resistance can be obtained in any of the examples.
In Example 21 and Example 22, a hard coat film was produced and evaluated in the same manner as in Example 1 except that the addition amount of the ultraviolet light absorber (B1) was changed as shown in Table 4. It turned out that sufficient abrasion resistance, base-material adhesiveness, and a weather resistance are obtained also in any Example.

Table 5 shows the results of various evaluations of the hard coat films of Examples 23 to 25.
In Example 23 and Example 25, a hard coat film was produced and evaluated in the same manner as in Example 1 except that the amount of the light stabilizer (D) added to the coating composition was changed as shown in Table 5. The It was found that sufficient scratch resistance, weather resistance and substrate adhesion could be obtained in any of the examples.

Claims (9)

(A) An energy ray curable (meth) acrylate monomer having a weight average molecular weight of 250 to 563 and an energy ray curable functional group number of 2 to 9 and a hydroxyl number of 1 or less,
(B) energy ray-curable functional group-containing ultraviolet absorber, and
(C) an energy ray curable oligomer which is a polyfunctional urethane (meth) acrylate oligomer having a weight average molecular weight of 1,500 to 20,000 and an energy ray curable functional group number of 10 to 20,
Coating composition characterized by mass ratio ((A) ingredient: (C) ingredient) of the above-mentioned (A) ingredient and (C) ingredient being 3: 97-50: 50. (A) Dipentaerythritol hexa (meth) acrylate, pentaerythritol tri (meth) acrylate, 1,6-hexanediol dimethacrylate, trimethylolpropane trioxyethyl (meth) acrylate, tris (2-hydroxyethyl) isocyanurate trioxide (Meth) acrylate, dipentaerythritol polyacrylate, dipentaerythritol hexaacrylate, tricyclodecane dimethanol diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, trimethylolpropane triacrylate, and ditrimethylolpropane tetraacrylate Energy ray curable (meth) acrylate monomers,
  (B) energy ray-curable functional group-containing ultraviolet absorber, and
  (C) An energy ray curable oligomer which is a polyfunctional urethane (meth) acrylate oligomer having a weight average molecular weight of 1,500 to 20,000 and an energy ray curable functional group number of 10 to 20
Contains
  Coating composition characterized by mass ratio ((A) ingredient: (C) ingredient) of the above-mentioned (A) ingredient and (C) ingredient being 3: 97-50: 50. (E1) A photopolymerization initiator having a maximum absorbance of 0.1 or more in a wavelength range of 340 nm to 400 nm of a 0.01% by mass methanol solution or acetonitrile solution, and a (E2) 0.001% by mass methanol solution The coating composition according to claim 1 or 2 , further comprising a photopolymerization initiator having a maximum absorbance of 0.1 or more in the wavelength range of 220 nm to 280 nm of the acetonitrile solution. The said (B) component is a ultraviolet absorber whose maximum value of the light absorbency in the wavelength range of 280 nm-370 nm in a 0.0619 mmol / l dichloromethane solution is 0.6 or more . The coating composition according to any one of the preceding claims. A hard coat film having a hard coat layer obtained from the coating composition according to any one of claims 1 to 4 on at least one surface of a transparent support. The thickness of the said hard-coat layer is 0.5 micrometer or more and 20 micrometers or less, The hard coat film of Claim 5 characterized by the above-mentioned. The base material adhesiveness of the said hard-coat layer and the said transparent support body is 90/100 or more based on JISK5400, The hard coat film of Claim 5 or 6 characterized by the above-mentioned. Temperature 60 ° C., relative humidity 90% H. The substrate adhesion of the transparent support and the hardcoat layer is from claim 5, characterized in that at 90/100 or more based on JIS K5400 7 of environment after moisture resistance test of leaving 550 hours The hard coat film according to any one of the items. The hard coat film according to any one of claims 5 to 8 , having a yellowing factor (? B) of less than 1 after 12 cycles of the weathering test specified in ASTM G-154.