laminate

Abstract

To provide a laminate which is excellent in surface hardness, scratch resistance, and low curling property, which is excellent in absorption of ultraviolet light and a visible light short wavelength region of more than or equal to 400 nm, and which furthermore includes a hard coat layer prevented from being yellowed.SOLUTION: Problems of the present invention are solved by a laminate including a hard coat layer which is a cured product of a specific ultraviolet curable composition on a transparent substrate, in which (1) to (5) below are all satisfied in a configuration including a hard coat layer having a thickness of 5 μm on a polyethylene terephthalate substrate: (1) a spectral transmittance of light having a wavelength of 410 nm is less than or equal to 5%; (2) a spectral transmittance of light having a wavelength of 450 nm is more than or equal to 70%; (3) a b* value is less than or equal to 20; (4) the hard coat layer has a modulus of elasticity of more than or equal to 3.0 GPa; and (5) a distance between both ends of a long side in a width direction of a test film which is 100 mm in length and 50 mm in width after being left for six hours in a high-temperature, high-humidity chamber at 23°C and a relative humidity of 50% is more than or equal to 45 mm.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a laminate.

Background Art

[0002] Base materials made of plastics such as polyethylene terephthalate resin are excellent in transparency, impact resistance, lightweight, and easy to process, so they are used in various applications instead of glass base materials.

[0003] However, since plastic base materials may be inferior in surface properties such as hardness and scratch resistance compared to glass base materials, a hard coat layer is provided on the plastic base material surface to improve surface properties such as hardness and scratch resistance.

[0004] Plastic base materials cannot sufficiently cut ultraviolet rays contained in sunlight and the like, and an ultraviolet absorber is often blended to prevent deterioration due to ultraviolet rays. For example, in a display device, an ultraviolet absorber is generally added to an optical film such as a polarizing plate protection film to prevent discoloration of these optical films. In addition, various organic substances such as fluorescent materials and phosphorescent materials are used for light-emitting elements of organic EL displays, and an ultraviolet absorber is added to a surface film of the display or the like to prevent deterioration of these organic substances due to ultraviolet rays. (Patent Document 1)

[0005] In addition, it has been pointed out that light in the short wavelength region of visible light (generally 380 to 495 nm), so-called blue light, emitted from sunlight or an image display device such as a smartphone damages the human body (especially the eyeball).

[0006] Patent Document 2 proposes a hard coat layer containing a yellow pigment, and it is described that the transmittance of light at 440 nm is 80% or less.

[0007] Methods of incorporating a blue light cut agent have also been proposed. In Patent Document 3, an ultraviolet curable hard coat resin composition having blue light cut properties has been proposed, and it is described that the composition absorbs light around 440 nm.

[0008] However, a cured product obtained by curing a composition containing a compound that absorbs light at 440 nm has a strong yellowish tint, which is the complementary color in that wavelength range, and is not suitable for display applications. In a hard coat layer containing a blue light cut agent with low pigment and solvent solubility, there is a problem that the haze value increases. Also, for display applications, it is necessary to have light resistance, that is, no change in ultraviolet absorption ability even when exposed to light for a long time.

[0009] In Patent Document 4, an optical film with a blue light shielding rate of 30% or more has been proposed, but the 410 nm transmittance is large, and the blue light cut property cannot be said to be sufficient.

[0010] Furthermore, the inventions described in Documents 1 to 4 have a problem that since a material that absorbs ultraviolet rays is mixed with an ultraviolet curable compound such as an acrylate compound, it is difficult to cure by ultraviolet rays, and the surface hardness and scratch resistance of the obtained cured product are insufficient. That is, the conventionally proposed optical films have insufficient surface scratch resistance, and further hard coat properties are required for use in display applications.

[0011] Generally, it is known to use polyfunctional acrylate compounds such as pentaerythritol triacrylate and dipentaerythritol hexaacrylate to enhance scratch resistance. However, when using polyfunctional acrylate compounds, the curl of the cured product becomes large, making it difficult to use in display applications. Therefore, there is a demand for a laminate having a hard coat layer with low curl property that can be used in display applications and excellent blue light cut performance and scratch resistance.

[0012] On the one hand, in recent years, in the field of display applications, in addition to the conventionally widely used liquid crystal displays (LCDs), various other displays have been developed. For example, organic electroluminescence (EL) displays have been rapidly spreading.

[0013] In a general organic EL display, a polarizing plate is laminated. The polarizing plate is mostly made of polyvinyl alcohol (PVA) which is water-soluble for easy adaptation to liquid crystals, and is manufactured by stretching it into a film shape after dyeing with iodine. Since the PVA polarizing plate has hygroscopicity, a triacetyl cellulose (TAC) film which is excellent in non-combustibility, appearance (transparency), and insulation as a protective film is used.

[0014] When adhering a polarizing plate made of PVA and a TAC film, it is necessary to saponify the surface of the TAC film with caustic alkali and hydrolyze a part of the acetyl group (-O=COCH group) on the surface of the TAC film into a hydroxyl group (-OH) which is a hydrophilic group.

[0015] The saponification treatment method of the TAC film is carried out by immersing the TAC film in an alkaline aqueous solution such as sodium hydroxide (NaOH) or potassium hydroxide (KOH). Therefore, when saponifying a laminate provided with a hard coat layer having a blue light cut function on the TAC film, elution of an ultraviolet absorber may occur, causing an increase in ultraviolet transmittance and elution (contamination) of the ultraviolet cut agent into the saponification treatment solution. In addition, since the TAC film has a high moisture permeability, there is a problem of causing deterioration under high temperature and high humidity conditions. Therefore, a polarizing plate using a resin film with a lower moisture permeability than the TAC film has been proposed. However, since the same production line as that of the TAC film is used, similar to the case of the TAC film, elution (contamination) of the ultraviolet cut agent into the above-mentioned saponification treatment solution may occur.

[0016] A laminate (a laminate having a hard coat layer with low curl properties and blue light cut performance) that can be used for display applications, which is excellent in surface hardness, scratch resistance, and low haze, and further has a suppressed yellowness, and has excellent light resistance and elution resistance, has not yet existed.

Prior Art Documents

Patent Documents

[0017]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Summary of the Invention

Problems to be Solved by the Invention

[0018] The present invention aims to provide a laminate that is excellent in low curl properties, absorption in the ultraviolet region and the short wavelength region of visible light of 400 nm or more, is excellent in surface hardness, scratch resistance, and low haze, further has a suppressed yellowness, and has excellent light resistance and elution resistance, and is provided with a hard coat layer.

Means for Solving the Problems

[0019] As a result of intensive studies to solve the above problems, the present inventors have arrived at the following inventions [1] to [3].

[0020] [1] A laminate having a hard coat layer on a transparent substrate, wherein the hard coat layer is a cured product of an ultraviolet curable composition containing a polymerizable compound (A), an ultraviolet absorber (B), and a photopolymerization initiator (C), The polymerizable compound (A) contains a compound (a1) having three or more (meth)acryloyl groups and a (meth)acryloyl group equivalent of 115 or more. The ultraviolet absorber (B) is a triazine compound that absorbs light with a wavelength of 400 to 420 nm. The photopolymerization initiator (C) contains at least one of an oxime ester compound (C1) and a phosphine oxide compound (C2). A laminate characterized by satisfying all of the following (1) to (5) in a configuration including a hard coat layer with a thickness of 5 μm on a polyethylene terephthalate substrate. (1) The spectral transmittance of light with a wavelength of 410 nm is 5% or less. (2) The spectral transmittance of light with a wavelength of 450 nm is 70% or more. (3) b * The value is 20 or less. (4) The elastic modulus of the hard coat layer is 3.0 GPa or more. (5) After leaving in a high temperature and high humidity chamber at 23 °C and a relative humidity of 50% for 6 hours, the distance between both ends in the width direction on the long side of a test film with a length of 100 mm × a width of 50 mm is 45 mm or more.

[0021] [2] The laminate according to [1], wherein the compound (a1) contains a polyfunctional urethane (meth)acrylate (a1x) having 4 to 15 (meth)acryloyl groups and a weight average molecular weight of 500 to 15,000.

[0022] [3] The laminate according to [1] or [2], wherein the ultraviolet absorber (B) has 1 to 3 naphthalene rings directly bonded to the triazine ring, and at least one of the naphthalene rings has a hydroxyl group at the 2-position.

Advantages of the Invention

[0023] According to the present invention described above, a laminate provided with a hard coat layer excellent in surface hardness, scratch resistance, low curl property, excellent in absorption of ultraviolet rays and visible light short wavelength region of 400 nm or more, and further suppressed in yellowness can be provided.

Modes for Carrying Out the Invention

[0024] Hereinafter, the present invention will be described in detail. Needless to say, other embodiments are also included in the scope of the present invention as long as they are consistent with the gist of the present invention. In addition, in this specification, a numerical range specified using "~" shall include the numerical values described before and after "~" as the range of the lower limit value and the upper limit value.

[0025] First, the terms used in this specification will be described. In addition, in this specification, when expressed as "(meth)acrylic", "(meth)acryloyl", and "(meth)acrylate", unless otherwise specified, they represent "acrylic or methacrylic", "acryloyl or methacryloyl", and "acrylate or methacrylate", respectively. Also, "polymerizable compound (A)" may be referred to as "compound (A)", and "photoinitiator (C)" may be referred to as "initiator (C)". Unless otherwise noted, each of the various components appearing in this specification may be used independently alone or in combination of two or more.

[0026] <Hard coat layer> The hard coat layer is a cured product of an ultraviolet curable composition containing a polymerizable compound (A), an ultraviolet absorber (B), and a photoinitiator (C).

[0027] Since the ultraviolet curable composition for forming the hard coat layer contains a polymerizable compound (A), an ultraviolet absorber (B), and a photoinitiator (C), it is excellent in surface hardness, scratch resistance, and low curl property, excellent in absorption of ultraviolet rays and the short wavelength region of visible light of 400 nm or more, and further, it is possible to form a laminate provided with a hard coat layer in which yellowing is suppressed.

[0028] In the present invention, the elastic modulus of the hard coat layer is 3.0 GPa or more. The elastic modulus of the hard coat layer is preferably 4.0 GPa or more, more preferably 4.5 GPa or more. Also, it is preferably 8.0 GPa or less, more preferably 6.5 GPa or less. If the elastic modulus is at least the above lower limit, even if an impact or scratch is imparted to the surface of the hard coat layer, it is difficult for a scratch to occur.

[0029] The elastic modulus of the hard coat layer can be obtained by measuring the surface of the hard coat layer using a nanoindenter under the condition of a penetration depth of 200 nm. Details of the measurement method will be described in the Examples section.

[0030] <Polymerizable compound (A)> The polymerizable compound (A) contains a compound (a1) having three or more (meth)acryloyl groups and a (meth)acryloyl group equivalent of 115 or more.

[0031] Here, the (meth)acryloyl group equivalent is determined by the following formula. (Meth)acryloyl group equivalent = weight average molecular weight / number of (meth)acryloyl groups in the same molecule

[0032] <Compound (a1)> The compound (a1) is not particularly limited as long as it has three or more (meth)acryloyl groups and a (meth)acryloyl group equivalent of 115 or more. For example, polyester (meth)acrylate, epoxy (meth)acrylate, urethane (meth)acrylate can be mentioned, but it is not limited thereto. From the viewpoint of being easy to balance surface hardness, scratch resistance, and low curl property, (a1) preferably contains urethane (meth)acrylate.

[0033] In order to obtain a hard coat layer excellent in surface hardness, scratch resistance, and low curl property, the content of the compound (a1) in 100% by mass of the compound (A) is preferably 70% by mass or more, more preferably 80% by mass or more, and still more preferably 90% by mass or more. When the content of the compound (a1) is within the above range, excellent surface hardness, scratch resistance, and low curl property can be satisfied.

[0034] <Polyester (meth)acrylate> The polyester (meth)acrylate can be obtained, for example, by reacting a polyester polycarboxylic acid obtained by polycondensing a polybasic acid and a polyhydric alcohol with a hydroxyl group-containing (meth)acrylate or the like. Examples of the above polybasic acids include aliphatic, alicyclic, and aromatic polybasic acids, and each can be used without particular limitation. For example, examples of aliphatic polybasic acids include oxalic acid, malonic acid, succinic acid, adipic acid, sebacic acid, azelaic acid, suberic acid, maleic acid, fumaric acid, dodecanedioic acid, pimelic acid, citraconic acid, glutaric acid, itaconic acid, succinic anhydride, maleic anhydride, etc. These aliphatic dicarboxylic acids and their anhydrides can be used. Also, derivatives of acid anhydrides can be used.

[0035] Examples of the above polyhydric alcohols include ethylene glycol, propylene glycol, dipropylene glycol, diethylene glycol, triethylene glycol, butylene glycol, 3-methyl-1,5-pentanediol, 2,4-diethyl-1,5-pentanediol, 2-methyl-1,8-octanediol, 3,3'-dimethylolheptane, 2-butyl-2-ethyl-1,3-propanediol, polyoxyethylene glycol (with an addition mole number of 10 or less), polyoxypropylene glycol (with an addition mole number of 10 or less), propane diol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,9-nonanediol, neopentyl glycol, octanediol, butylethylpentanediol, 2-ethyl-1,3-hexanediol, cyclohexanediol, cyclohexanedimethanol, tricyclodecanedimethanol, cyclopentadienedimethanol, dimer diol, and other aliphatic or alicyclic diols.

[0036] Also, a polyol containing three or more hydroxyl groups such as glycerin, trimethylolpropane, pentaerythritol, dipentaerythritol, etc. may be partially used.

[0037] Among the above polyhydric alcohols, those in which two or more hydroxyl groups are introduced into branched alkanes such as neopentyl glycol, 3-methyl-1,5-pentanediol, 2,4-diethyl-1,5-pentanediol, 2-methyl-1,8-octanediol, 3,3'-dimethylolheptane, 2-butyl-2-ethyl-1,3-propanediol, butylethylpentanediol, 2-ethyl-1,3-hexanediol, trimethylolpropane, etc. are preferable in terms of the adhesiveness, heat resistance, etc. of the oligomer.

[0038] Examples of the hydroxyl group-containing (meth)acrylate include the same ones as described above. Among them, those containing at least one selected from trimethylolpropane di(meth)acrylate, trimethylolethane di(meth)acrylate, pentaerythritol tri(meth)acrylate, and dipentaerythritol penta(meth)acrylate are preferable.

[0039] <Epoxy (meth)acrylate> The polyepoxy (meth)acrylate can be obtained, for example, by esterifying the glycidyl group of an epoxy resin with (meth)acrylic acid to convert the functional group into a (meth)acrylate group.

[0040] <Urethane (meth)acrylate> Urethane (meth)acrylate can be obtained, for example, by reacting a diisocyanate with (meth)acrylates having a hydroxyl group, by reacting an isocyanurate (trimer) of a diisocyanate with (meth)acrylates having a hydroxyl group, by reacting an isocyanurate (trimer) of a polyisocyanate with a polyol and (meth)acrylates having a hydroxyl group, or by reacting an isocyanate group-containing urethane prepolymer obtained by reacting a polyol and a polyisocyanate under conditions of an excess of isocyanate groups with (meth)acrylates having a hydroxyl group. Alternatively, it can also be obtained by reacting a hydroxyl group-containing urethane prepolymer obtained by reacting a polyol and a polyisocyanate under conditions of an excess of hydroxyl groups with (meth)acrylates having an isocyanate group.

[0041] Known ones can be used as the above diisocyanate and polyisocyanate, and examples include aromatic diisocyanates, aliphatic diisocyanates, and alicyclic diisocyanates. Examples of aromatic diisocyanates include 1,5-naphthylene diisocyanate, 4,4'-diphenylmethane diisocyanate (MDI), 4,4'-diphenyldimethylmethane diisocyanate, 4,4'-dibenzyl isocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, tolylene diisocyanate, m-tetramethylxylylene diisocyanate, 4,4-diphenylmethane diisocyanate, xylylene diisocyanate, and 2,6-diisocyanate-benzyl chloride. Examples of aliphatic diisocyanates include butane-1,4-diisocyanate, hexamethylene diisocyanate, isopropylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, and lysine diisocyanate. Examples of the alicyclic diisocyanate include cyclohexane-1,4-diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate, dimer diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, 1,3-bis(isocyanatemethyl)cyclohexane, methylcyclohexane diisocyanate, norbornane diisocyanate, and dimer diisocyanate obtained by converting the carboxy group of dimer acid into an isocyanate group. Among them, aliphatic diisocyanate and alicyclic diisocyanate are preferable from the viewpoint of suppressing yellowing when assuming optical applications.

[0042] Examples of the hydroxyl group-containing (meth)acrylate include trimethylolpropane di(meth)acrylate, trimethylolethane di(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol penta(meth)acrylate, 2-hydroxyethyl (meth)acrylate, 1-hydroxypropyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 1-hydroxybutyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, cyclohexanedimethanol mono(meth)acrylate ester, 10-hydroxydecyl (meth)acrylate, 12-hydroxylauryl (meth)acrylate, ethyl-α-(hydroxymethyl) (meth)acrylate, monofunctional glycerol (meth)acrylate, or (meth)acrylate esters having a hydroxyl group at the terminal by ring-opening addition of ε-caprolactone lactone to these (meth)acrylates, and alkylene oxide-added (meth)acrylate esters obtained by repeatedly adding alkylene oxides such as ethylene oxide, propylene oxide, and butylene oxide to the above hydroxyl group-containing (meth)acrylates. From the viewpoints of increasing the crosslinking density and suppressing damage, curl generation, elution of the ultraviolet absorber (B), etc., a (meth)acrylic acid ester having 2 to 5 (meth)acryloyl groups is preferable. Specifically, it preferably contains at least one selected from trimethylolpropane di(meth)acrylate, trimethylolethane di(meth)acrylate, pentaerythritol tri(meth)acrylate, and dipentaerythritol penta(meth)acrylate.

[0043] Urethane (meth)acrylate is roughly classified into a polyfunctional urethane (meth)acrylate (a1x) having 4 to 15 (meth)acryloyl groups and a weight average molecular weight of 500 to 15,000, and a polyfunctional urethane (meth)acrylate (a1y) other than (a1x). Among these, the polyfunctional urethane (meth)acrylate (a1x) having 4 to 15 (meth)acryloyl groups and a weight average molecular weight of 500 to 15,000 is preferable. By including (a1x), a laminate with a high elastic modulus of the hard coat layer of the laminate and further excellent low curl property can be formed.

[0044] In particular, in order to obtain a hard coat layer excellent in surface hardness and scratch resistance, the content of the compound (a1x) in 100% by mass of the compound (a1) is preferably 60% by mass or more, more preferably 70% by mass or more, and still more preferably 85% by mass or more.

[0045] <Polyfunctional urethane (meth)acrylate (a1x)> The polyfunctional urethane (meth)acrylate (a1x) is a polyfunctional urethane (meth)acrylate having 4 to 15 (meth)acryloyl groups and a weight average molecular weight of 500 to 15,000. The weight average molecular weight is preferably 1,000 to 5,000. By using (a1x) within the above weight average molecular weight range, a laminate excellent in surface hardness and scratch resistance and further excellent in low curl property can be formed. The weight average molecular weight (Mw) is the weight average molecular weight in terms of polystyrene determined by gel permeation chromatography (GPC) measurement. The weight average molecular weight can be measured by the method described in the section of [Examples].

[0046] The manufacturing method of the polyfunctional urethane (meth)acrylate (a1x) is shown below. This is an example and is not limited thereto. For example, the polyfunctional urethane (meth)acrylate (a1x) can be obtained by stirring a polyisocyanate and a hydroxyl group-containing (meth)acrylate in the presence of a suitable urethanization catalyst under an oxygen atmosphere at 60 to 100°C for 4 to 8 hours. Specific examples of the urethanization catalyst include copper naphthenate, cobalt naphthenate, zinc naphthenate, dibutyltin dilaurate, triethylamine, 1,4-diazabicyclo[2.2.2]octane, 2,6,7-trimethyl-1,4-diazabicyclo[2.2.2]octane, and the like. Among these, dibutyltin dilaurate and the like are particularly preferred. As the polyisocyanate and the hydroxyl group-containing (meth)acrylate, the same ones as those described in the description of the urethane (meth)acrylate can be used.

[0047] The number of (meth)acryloyl groups and the weight average molecular weight can be adjusted by the combination of a polyol, a polyisocyanate, and a hydroxyl group-containing mono(meth)acrylate or poly(meth)acrylate.

[0048] Specific examples of polyfunctional urethane (meth)acrylates (a1x) whose weight average molecular weight and number of acryloyl groups are published in catalogs, etc., include Shiko UV1700B (weight average molecular weight 2000, number of acryloyl groups 10), UV7600B (weight average molecular weight 1400, number of acryloyl groups 6), UV7605B (weight average molecular weight 1100, number of acryloyl groups 6), UV7610B (weight average molecular weight 1100, number of acryloyl groups 9), U V7629EA (weight average molecular weight 4100, number of acryloyl groups 9, volatile content 35%), UV7640B (weight average molecular weight 1500, number of acryloyl groups 6-7), and UV7650B (weight average molecular weight 2300, number of acryloyl groups 4-5); MIWON Co., Ltd.: Miramer PU610 (weight average molecular weight 1800, number of acryloyl groups 6), and MU9500 (weight average molecular weight 3200, number of acryloyl groups 10); Nippon Kayaku Co., Ltd.: KAYARAD DPHA-40H (weight average molecular weight 2000, number of acryloyl groups 10), UX-5000 (weight average molecular weight 1500, number of acryloyl groups 6), UX-5102D-M20 (weight average molecular weight 3500, number of acryloyl groups 6) Examples of the resins include, but are not limited to, Art Resin UN-3320HA (weight average molecular weight 1500, number of acryloyl groups 6), UN-3320HC (weight average molecular weight 1500, number of acryloyl groups 15, volatile content 5%), UN-904 (weight average molecular weight 4900, number of acryloyl groups 10), UN-906S (weight average molecular weight 1000, number of acryloyl groups 6), UN-901T (weight average molecular weight 4000, number of acryloyl groups 9, volatile content 20%), and UN-952 (weight average molecular weight 6500 to 11000, number of acryloyl groups 10), manufactured by Negami Chemical Industries, Ltd.

[0049] The hard coat agent of the present invention may contain a polymerizable compound other than the compound (a1) as the compound (A) as necessary. As an example, compounds (a2) having three or more (meth)acryloyl groups and having a (meth)acryloyl group equivalent weight of less than 115, and compounds (a3) having one or two (meth)acryloyl groups can be mentioned.

[0050] Specific examples of the compound (a2) having three or more (meth)acryloyl groups and having a (meth)acryloyl group equivalent weight of less than 115 include polyol poly(meth)acrylate compounds such as trimethylolpropane tri(meth)acrylate, glycerin tri(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, pentaerythritol tri(meth)acrylate, and pentaerythritol tetra(meth)acrylate; In addition, polyacrylates of polymer polyols such as polyacryl poly(meth)acrylate, polyurethane poly(meth)acrylate, and polyester (meth)acrylate, which have three or more (meth)acryloyl groups; polyepoxy (meth)acrylate; and the like, but are not limited thereto.

[0051] Examples of commercially available products of compound (a2) include, for example, polyol poly(meth)acrylate compounds such as trimethylolpropane tri(meth)acrylate (Miramer M300 manufactured by MIWON Co., Ltd., etc.), glycerin tri(meth)acrylate (Aronix M-930 manufactured by Toagosei Co., Ltd., etc.), dipentaerythritol penta(meth)acrylate (SR399 manufactured by Sartomer Co., Ltd., etc.), dipentaerythritol hexa(meth)acrylate (Miramer M600 manufactured by MIWON Co., Ltd., etc.), pentaerythritol tri(meth)acrylate (Miramer M340 manufactured by MIWON Co., Ltd., etc.), and pentaerythritol tetra(meth)acrylate (Light Acrylate PE-4A manufactured by Kyoeisha Chemical Co., Ltd., etc.); and the like, but are not limited thereto.

[0052] Examples of the compound (a3) having one or two (meth)acryloyl groups include di(meth)acrylates such as 1,3-butanediol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, diethylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, and ethylene oxide-modified di(meth)acrylate of bisphenol A; oligomers such as polyurethane poly(meth)acrylate and polyester poly(meth)acrylate; and mono(meth)acrylates such as 2-ethylhexyl (meth)acrylate, isodecyl (meth)acrylate, isooctyl (meth)acrylate, benzyl (meth)acrylate, cyclopentanyl (meth)acrylate, cyclohexyl (meth)acrylate, dicyclopentenyl (meth)acrylate, and isobornyl (meth)acrylate. However, the examples are not limited thereto.

[0053] <Ultraviolet absorber (B)> The ultraviolet absorber (B) is a triazine compound that absorbs light with a wavelength of 400 to 420 nm, and preferably has an absorbance of 0.1 or more over the entire region at a wavelength of 400 to 420 nm. Furthermore, it more preferably has a structure having 1 to 3 naphthalene rings directly bonded to the triazine ring, and at least one of the naphthalene rings has a hydroxyl group at the 2-position. Due to the action of the naphthalene ring directly bonded to the triazine ring, it can absorb light in the short-wavelength visible light region of about 400 to 420 nm in addition to the ultraviolet region of less than 400 nm, which is preferable. In addition, an ultraviolet absorber having 1 to 3 naphthalene rings directly bonded to the triazine ring, and at least one of the naphthalene rings having a hydroxyl group at the 2-position, has an unexpected effect that desired wavelength absorption can be achieved with a smaller amount of addition than in the past, and a cured product with suppressed yellowness can be obtained.

[0054] In order to obtain a hard coat layer that is excellent in absorbing ultraviolet rays and visible light in the short wavelength region of 400 nm or more, the content of the ultraviolet absorber (B) is preferably 3% by mass or more, more preferably 5% by mass or more, and still more preferably 7% by mass or more with respect to 100% by mass of the compound (A). Also, in order to obtain a hard coat layer with suppressed yellowness, the content of the ultraviolet absorber (B) is preferably 20% by mass or less, more preferably 15% by mass or less with respect to 100% by mass of the compound (A).

[0055] As the ultraviolet absorber (B), a compound selected from the group consisting of the following general formula (1), general formula (2), and general formula (3) is preferable.

[0056] General formula (1) TIFF2025092996000001.tif87162 General formula (2) TIFF2025092996000002.tif76164 General formula (3) TIFF2025092996000003.tif68149

[0057] (In general formulas (1) to (3), R 1b ~R 1g , R 2a ~R 2g , R 3a ~R 3g are each independently a hydrogen atom, a hydroxyl group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a nitrile group, a nitro group, a sulfo group, R7, Ar1, or a group represented by the following general formulas (4-1) to (4-3). R7 is an alkyl group which may have a branched chain with 1 to 20 carbon atoms, an alkenyl group which may have a branched chain with 1 to 20 carbon atoms, an alkoxy group which may have a branched chain with 1 to 20 carbon atoms, or an alkenyloxy group which may have a branched chain with 1 to 20 carbon atoms, and may have a substituent of a hydroxyl group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a nitrile group, a nitro group, a carboxyl group, or a sulfo group. The carbon atoms of the alkyl group which may have a branched chain with 1 to 20 carbon atoms, the alkenyl group which may have a branched chain with 1 to 20 carbon atoms, the alkoxy group which may have a branched chain with 1 to 20 carbon atoms, or the alkenyloxy group which may have a branched chain with 1 to 20 carbon atoms may be linked by one or more of -O-, -CO-, -COO-, -OCO-, -CONH-, or -NHCO-. Ar1 is an aryl group with 6 to 20 carbon atoms, an aryloxy group with 6 to 20 carbon atoms, or a biphenyl group, and may have a substituent of a hydroxyl group, an alkyl group which may have a branched chain with 1 to 20 carbon atoms, an alkenyl group which may have a branched chain with 1 to 20 carbon atoms, an aryl group with 6 to 20 carbon atoms, an alkoxy group which may have a branched chain with 1 to 20 carbon atoms, an alkenyloxy group which may have a branched chain with 1 to 20 carbon atoms, an aryloxy group with 6 to 20 carbon atoms, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a nitrile group, a nitro group, a carboxyl group, or a sulfo group. In general formulas (2) to (3), R4, R5, and R6 are a hydroxyl group, R7, or Ar1. General formula (4-1)

Chemical formula

[0058] In general formula (4-1), X1 is -CO-, -COO-, -OCO-, -CONH-, or -NHCO-. R8 is a hydrogen atom, a hydroxyl group, R7, or Ar1. However, * in general formula (4-1) represents the bonding site with the naphthalene ring of general formulas (1) to (3). General formula (4-2)

Chemical formula

[0059] In general formula (4-2), X2 and X3 are each independently -CO-, -COO-, -OCO-, -CONH-, or -NHCO-. R9 is an arylene group having 6 to 20 carbon atoms. R 10 is R7 or Ar1. However, * in general formula (4-2) represents the bonding site with the naphthalene ring of general formulas (1) to (3). General formula (4-3)

Chemical formula

[0060] In general formula (4-3), X4 and X5 are each independently -CO-, -COO-, -OCO-, -CONH-, or -NHCO-. R 11 is a linear or branched alkylene group having 1 to 20 carbon atoms, or an arylene group having 6 to 20 carbon atoms. R 12 is R7 or Ar1. n is 1 to 20. However, * in general formula (4-3) represents the bonding site with the naphthalene ring of general formulas (1) to (3).)

[0061] Note that general formula (4-1) preferably has a group containing general formula (4).

[0062] General formula (4)

Chemical formula

[0063] In general formula (4), Y is -NH- or -O-. R 13is an alkyl group having 1 to 20 carbon atoms which may have a branched chain, an alkenyl group having 1 to 20 carbon atoms which may have a branched chain, an aryl group having 6 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms which may have a branched chain, an alkenyloxy group having 1 to 20 carbon atoms which may have a branched chain, an aryloxy group having 6 to 20 carbon atoms, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a nitrile group, a nitro group, a carboxyl group, or a sulfo group, or an aryl group having 6 to 20 carbon atoms which may have a substituent. However, the * mark in the general formula (4) represents the bonding site with the naphthalene ring of the general formulas (1) to (3).

[0064] Examples of the compound represented by the general formula (1) include the following compounds. (B1) TIFF2025092996000008.tif57116(B2) TIFF2025092996000009.tif62132(B3) TIFF2025092996000010.tif57116(B4) TIFF2025092996000011.tif66147(B5) TIFF2025092996000012.tif64168(B6) TIFF2025092996000013.tif46114 (B7) TIFF2025092996000014.tif64166 (B8) TIFF2025092996000015.tif53120

[0065] Examples of the compound represented by the general formula (2) include the following compounds. (B9) TIFF2025092996000016.tif53113

[0066] Examples of the compound represented by the general formula (3) include the following compounds. (B10) TIFF2025092996000017.tif57120

[0067] The synthesis method of the above triazine compound can be carried out using a known synthesis method of a compound having a triazine structure. For example, a method of adding naphthol or a naphthol derivative to cyanuric chloride using aluminum trichloride can be mentioned. In addition, for example, a method of subjecting methyl 2-hydroxy-1-naphthoate and benzamidine hydrochloride to a condensation cyclization reaction using sodium methoxide can also be mentioned. The naphthalene ring linked to the triazine ring by a single bond and the substituents provided by R4, R5, and R6 may be introduced after forming the triazine structure or before forming the triazine structure.

[0068] <Photoinitiator (C)> The photoinitiator (C) contains at least one of an oxime ester compound (C1) and a phosphine oxide compound (C2). Since the oxime ester compound (C1) and the phosphine oxide compound (C2) have absorption at a wavelength of 400 nm or more, even if the ultraviolet rays necessary for photoexcitation of the photoinitiator are cut off by the ultraviolet absorber (B), radicals can be efficiently generated with a small amount of ultraviolet rays. Among them, it is preferable to use an oxime ester compound (C1) that can obtain a hard coat layer excellent in surface curability.

[0069] Examples of the oxime ester compound (C1) include, but are not limited to, Irgacure OXE01, Irgacure OXE02, Irgacure OXE03, etc. manufactured by BASF Co., Ltd.

[0070] Examples of the phosphine oxide compound (C2) include, but are not limited to, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, and 4-n-propylphenyl-di(2,6-dichlorobenzoyl)phosphine oxide, etc.

[0071] The blending amount of the photoinitiator (C) is preferably 0.1 to 30% by mass, more preferably 3 to 20% by mass, and even more preferably 5 to 10% by mass with respect to 100% by mass of the polymerizable compound (A). By being within this range, a sufficient polymerization initiation effect can be obtained, which is effective in improving the surface hardness and scratch resistance.

[0072] Further, a photoinitiator (C3) other than the oxime ester-based compound (C1) and the phosphine oxide-based compound (C2) may be used in combination. Examples of (C3) include monocarbonyl-based photoinitiators, dicarbonyl-based photoinitiators, acetophenone-based photoinitiators, benzoin ether-based photoinitiators, aminocarbonyl-based photoinitiators, and the like.

[0073] Specifically, for example, monocarbonyl-based photoinitiators such as benzophenone, 4-methylbenzophenone, 2,4,6-trimethylbenzophenone, methyl-o-benzoylbenzoate, 4-phenylbenzophenone, 3,3’,4,4’-tetra(t-butylperoxycarbonyl)benzophenone, 2- / 4-isopropylthioxanthone, 2,4-diethylthioxanthone, 2,4-dichlorothioxanthone, and 1-chloro-4-propoxythioxanthone; dicarbonyl-based photoinitiators such as 2-ethylanthraquinone, 9,10-phenanthrenequinone, and methyl-α-oxobenzenacetate; acetophenone-based photoinitiators such as 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-(4-isopropylphenyl)-2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxy-cyclohexylphenylketone, diethoxyacetophenone, dibutoxyacetophenone, 2,2-dimethoxy-1,2-diphenylethane-1-one, 2,2-diethoxy-1,2-diphenylethane-1-one, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butan-1-one, and 1-phenyl-1,2-propanedione-2-(o-ethoxycarbonyl)oxime; Benzoin ether-based photoinitiators such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, and benzoin normal butyl ether; And aminocarbonyl-based photoinitiators such as ethyl-4-(dimethylamino)benzoate, 2-n-butoxyethyl-4-(dimethylamino)benzoate, isoamyl-4-(dimethylamino)benzoate, 2-(dimethylamino)ethyl benzoate, 4,4'-bis-4-dimethylaminobenzophenone, 4,4'-bis-4-diethylaminobenzophenone, and 2,5'-bis(4-diethylaminobenzal)cyclopentanone; And the like.

[0074] Commercially available products of the photoinitiator (C3) include Omnirad184, 651, 500, 907, 127, 369, 784, 2959, Esacure One, etc. manufactured by IGM-Resins B.V.

[0075] <Sensitizer (D)> The ultraviolet curable composition can use the photoinitiator (C) and the sensitizer (D) in combination. Examples of the sensitizer (D) include amine-based sensitizers, anthracene-based sensitizers, thioxanthone-based sensitizers, etc. The sensitizers can be used alone or in combination of two or more.

[0076] Examples of the amine-based sensitizer include trimethylamine, methyldiethanolamine, triethanolamine, p-diethylaminoacetophenone, ethyl p-dimethylaminobenzoate (EPA), isoamyl p-dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate, N,N-dimethylbenzylamine, 4'-bis(diethylamino)benzophenone, etc. Examples of the anthracene-based sensitizer include 9,10-dibutoxyanthracene (DBA), 9,10-diethoxyanthracene (DEA), 9,10-dipropoxyanthracene, 9,10-bis(2-ethylhexyloxy)anthracene, etc.

[0077] Examples of thioxanthone-based sensitizers include thioxanthone-based sensitizers such as 2,4-diethylthioxanthone (DETX), 2-isopropylthioxanthone (ITX), and 4-isopropylthioxanthone.

[0078] Typical examples of commercially available products include, among amine-based sensitizers, KAYACURE KAYACURE EPA manufactured by Nippon Kayaku Co., Ltd.; among anthracene-based sensitizers, Anthracure UVS-1331 (DBA) and UVS-1101 (DEA) manufactured by Air Water Performance Chemicals Co., Ltd.; and among thioxanthone-based sensitizers, Omnirad DETX and ITX manufactured by IGM Resins B.V.

[0079] Sensitizers that absorb up to around 420 nm, which is on the longer wavelength side than the ultraviolet cut-off region, are preferred, and thioxanthone-based sensitizers, or a combination of amine-based sensitizers and thioxanthone-based sensitizers, are preferred.

[0080] When using a sensitizer, its content is preferably 1 to 15% by mass with respect to 100% by mass of the polymerizable compound (A).

[0081] <Other components> The ultraviolet curable composition may contain other components such as an organic solvent (E) and additives, if necessary. Examples of additives include thermosetting resins, polymerization inhibitors, leveling agents (F), slip agents, defoaming agents, surfactants, antibacterial agents, antiblocking agents, plasticizers, infrared absorbers, antioxidants, silane coupling agents, conductive agents, inorganic fillers, pigments, dyes, and the like.

[0082] <Organic solvent (E)> The ultraviolet curable composition may contain an organic solvent (E). As the organic solvent (E), known organic solvents such as aromatic organic solvents such as toluene and xylene, ketone organic solvents such as methyl ethyl ketone and methyl isobutyl ketone, ester organic solvents such as ethyl acetate, n-propyl acetate, isopropyl acetate, isobutyl acetate, alcohol organic solvents such as methanol, ethanol, n-propanol, isopropanol, n-butanol, and glycol ether organic solvents such as propylene glycol monomethyl ether can be used.

[0083] When the organic solvent (E) is included, from the viewpoints of coatability and film-forming property, the content of the organic solvent (E) is preferably in a range such that the nonvolatile content concentration of the coating composition of the present invention is 1 to 60% by mass.

[0084] <Leveling agent (F)> The ultraviolet curable composition can contain a leveling agent (F) according to the performance to be imparted to the hard coat layer to be formed. The leveling agent is not particularly limited as long as a desired leveling effect, that is, an effect of suppressing coating defects such as repellency during coating and an effect of smoothing the surface of the formed coat layer can be obtained. Examples of such leveling agents include silicone-based leveling agents, fluorine-based leveling agents, acrylic-based leveling agents, siloxane-modified acrylic-based leveling agents, and vinyl-based leveling agents.

[0085] As the silicone leveling agent, a copolymer of polyoxyalkylene and polydimethylsiloxane or the like can be used. Examples of commercially available silicone leveling agents include FZ-2118, FZ-77, FZ-2161, etc. manufactured by Toray Dow Corning Co., Ltd., KP321, KP323, KP324, KP326, KP340, KP341, etc. manufactured by Shin-Etsu Chemical Co., Ltd., TSF4440, TSF4441, TSF4445, TSF4450, TSF4446, TSF4452, TSF4453, TSF4460, etc. manufactured by Momentive Performance Materials Japan Co., Ltd., and polyester-modified silicone oils such as BYK-300, BYK-302, BYK-306, BYK-307, BYK-320, BYK-325, BYK-330, BYK-331, BYK-333, BYK-337, BYK-341, BYK-344, BYK-345, BYK-346, BYK-348, BYK-377, BYK-378, BYK-UV3500, BYK-UV3510, BYK-UV3570, etc. manufactured by BYK-Chemie Japan Co., Ltd.

[0086] As the fluorine-based leveling agent, a copolymer of polyoxyalkylene and fluorocarbon or the like can be used. Examples of commercially available fluorine-based leveling agents include the Megafac series manufactured by DIC Corporation, the FC series manufactured by Sumitomo 3M Limited, etc.

[0087] Examples of commercially available acrylic leveling agents include BYK-350, BYK-352, BYK-354, BYK-355, BYK-358N, BYK-361N, BYK-380N, BYK-381, BYK-392, etc. manufactured by BYK-Chemie Japan Co., Ltd.

[0088] Examples of commercially available siloxane-modified acrylic leveling agents include BYK-3550, etc. manufactured by BYK-Chemie Japan Co., Ltd.

[0089] The above leveling agents may be used alone or in combination of two or more. ​

[0090] <Laminate> The laminate of the present invention is not particularly limited as long as it has a hard coat layer which is a cured product of the ultraviolet curable composition on a transparent substrate.

[0091] <Transparent substrate> The transparent substrate used in the present invention is not particularly limited, and examples thereof include glass, synthetic resin moldings, and films. Examples of the synthetic resin molding include moldings of synthetic resins such as polymethyl methacrylate resin, copolymer resin mainly composed of methyl methacrylate, polystyrene resin, styrene-methyl methacrylate copolymer resin, styrene-acrylonitrile copolymer resin, polycarbonate resin, cellulose acetate butyrate resin, polyallyl diglycol carbonate resin, polyvinyl chloride resin, and polyester resin.

[0092] Examples of the film include polyester film, polyethylene film, polyethylene terephthalate film, polypropylene film, cellophane film, diacetyl cellulose film, triacetyl cellulose (TAC) film, acetyl cellulose butyrate film, polyvinyl chloride film, polyvinylidene chloride film, polyvinyl alcohol film, ethylene vinyl alcohol film, polyolefin film, polystyrene film, polycarbonate film, polymethylpentene film, polysulfone film, polyether ether ketone film, polyether sulfone film, polyether imide film, polyimide film, fluororesin film, nylon film, acrylic film, and the like.

[0093] The film substrate used in the present invention may be an optically transparent grade, and the thickness of the film substrate is not particularly limited, but is generally about 10 to 500 μm from the viewpoints of strength, workability such as handling, and thin layer properties. Particularly, 20 to 250 μm is preferable.

[0094] <Hard coat layer> The film thickness of the hard coat layer is not particularly limited as long as it has hard coat properties, and is usually 1 to 20 μm, preferably 2 to 15 μm. The film thickness of the laminate is not particularly limited, but is preferably 15 to 300 μm, more preferably 20 to 100 μm, and even more preferably 25 to 75 μm.

[0095] The laminate of the present invention satisfies all of the following (1) to (5) in a configuration including a hard coat layer with a thickness of 5 μm on a polyethylene terephthalate substrate. (1) The spectral transmittance of light with a wavelength of 410 nm is 5% or less. (2) The spectral transmittance of light with a wavelength of 450 nm is 70% or more. (3) b * The value is 20 or less. (4) The elastic modulus of the hard coat layer is 3.0 GPa or more. (5) After leaving a test film with a length of 100 mm and a width of 50 mm in a high-temperature and high-humidity chamber at 23 °C and a relative humidity of 50% for 6 hours, the distance between both ends in the width direction on the long side is 45 mm or more. From the viewpoint of blue light cut, the spectral transmittance of light with a wavelength of 410 nm is preferably 4% or less, and more preferably 3% or less. From the viewpoint of suppressing the yellowness of the laminate, the spectral transmittance of light with a wavelength of 450 nm is preferably 75% or more, and more preferably 80% or more. Similarly, the b* value is preferably 15 or less, and more preferably 10 or less.

[0096] <Manufacture of laminate> The manufacturing method of the laminate can be manufactured by a conventionally known method such as coating an ultraviolet curable composition on a transparent substrate, and is not particularly limited. For example, after coating the ultraviolet curable composition of the present invention on a polyethylene terephthalate substrate, the solvent is dried if necessary. By irradiating active energy rays thereto, the coated ultraviolet curable composition is crosslinked and cured to obtain a laminate having a polyethylene terephthalate substrate and a hard coat layer.

[0097] Examples of coating methods include bar coating, blade coating, spin coating, reverse coating, die coating, spray coating, roll coating, gravure coating, microgravure coating, lip coating, air knife coating, dipping method, and the like.

[0098] As the active energy ray, an electron beam or ultraviolet rays emitted from light sources such as a xenon lamp, a low-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a metal halide lamp, a carbon arc lamp, and a tungsten lamp can be used.

Examples

[0099] Hereinafter, the present invention will be described in more detail. The present invention is not limited to the examples. Note that "parts by mass" will be described as "parts", and "mass%" will be described as "%"

[0100] The ultraviolet absorber (B) used in the examples was prepared as follows.

[0101] <Ultraviolet absorber (B1)> 170 parts of chlorobenzene, 43.4 mmol of cyanuric chloride, and 65.1 mmol of aluminum chloride were charged into a 300 mL Erlenmeyer flask and stirred to form a suspension. Next, 151.8 mmol of 2-naphthol was added little by little while cooling with ice water. Then, the mixture was stirred overnight while gradually returning to room temperature. On the other hand, 38.1 parts of water, 10.0 parts of 35% hydrochloric acid, and 45.0 parts of methanol were charged into a 500 mL beaker, and the previous reaction solution was added dropwise little by little. Further, 45.0 parts of methanol was added to the Erlenmeyer flask in multiple portions and added to the 500 mL beaker while washing. The precipitate was filtered off and sprinkled and washed with a mixed solvent of water / methanol = 75 parts / 75 parts. The obtained wet cake was returned to 150 parts of water and slurried at room temperature for 30 minutes and then filtered. Thereafter, it was sprinkled and washed with 150 parts of water. The obtained wet cake was dried at 80 °C overnight to obtain an ultraviolet absorber (B1).

[0102] As a result of performing NMR measurement on the ultraviolet absorber (B1), results supporting the above structure were obtained. The measurement conditions are as follows. <Measurement conditions> Apparatus: BRUKER AVANCE400 Resonance frequency: 400 MHz (1H-NMR) Solvent: Dimethyl sulfoxide-d8 As the internal standard substance for 1H-NMR, tetramethylsilane was used, and the chemical shift value was shown as the δ value (ppm), and the coupling constant was shown in Hertz. Also, s is the abbreviation for singlet, d is for doublet, and m is for multiplet. The content of the obtained NMR spectrum is as follows. δ = 12.05 (s, 3H), 8.70 (d, J = 8.4 Hz, 3H), 8.07 (d, J = 8.8 Hz, 3H), 7.93 (d, J = 8.0 Hz, 3H), 7.46 - 7.50 (m, 3H), 7.38 - 7.42 (m, 3H), 7.34 (d, J = 9.2 Hz, 3H)

[0103] As described above, in this specification, the structure of the ultraviolet absorber (B1) was identified by NMR as an example. The structures of other ultraviolet absorbers were also identified by NMR in the same manner as above, but the data are omitted.

[0104] <Ultraviolet absorber (B2)> Into a 200 mL Erlenmeyer flask, 100 g of N-methyl-2-pyrrolidone, 20.0 mmol of the ultraviolet absorber (B1), and 40.0 mmol of potassium carbonate were charged, and the mixture was heated to 90 °C with stirring. Next, 40.0 mmol of 1-bromo-2-ethylhexane was charged, and the mixture was stirred at 90 °C for 4 hours. On the other hand, 500 g of water was charged into a 1 L beaker, and the previous reaction solution was added dropwise little by little. The precipitate was filtered off and washed by sprinkling with 500 g of water. The obtained wet cake was returned to 500 g of water, slurried at room temperature for 30 minutes, and then filtered off. Thereafter, it was washed by sprinkling with 500 g of water. The obtained wet cake was dried at 80 °C overnight to obtain the ultraviolet absorber (B2).

[0105] <Ultraviolet absorber (B3)> Into a 200 mL Erlenmeyer flask, 100 g of N-methyl-2-pyrrolidone, 20.0 mmol of ultraviolet absorber (B1), and 20.0 mmol of potassium carbonate were charged, and the mixture was heated to 90 °C with stirring. Next, 20.0 mmol of 1-bromobutane was charged, and the mixture was stirred at 90 °C for 4 hours. On the other hand, 500 g of water was charged into a 1 L beaker, and the previous reaction solution was added dropwise little by little. The precipitate was filtered off and washed by sprinkling with 500 g of water. The obtained wet cake was returned to 500 g of water and slurried at room temperature for 30 minutes, and then filtered off. Thereafter, it was washed by sprinkling with 500 g of water. The obtained wet cake was dried at 80 °C overnight to obtain ultraviolet absorber (B3).

[0106] <Ultraviolet absorber (B4)> Into a 200 mL Erlenmeyer flask, 100 parts of N-methyl-2-pyrrolidone and 20.0 mmol of 2-methacryloyloxyethyl succinate (Light ester HO-MS(N), manufactured by Kyoeisha Chemical Co., Ltd.) were charged, and the mixture was stirred while being ice-cooled. 20 mmol of thionyl chloride was added dropwise, and the mixture was stirred for 2 hours while being ice-cooled. Thereafter, 20.0 mmol of ultraviolet absorber (B1) was charged, and the mixture was stirred at room temperature for 4 hours. On the other hand, 500 parts of water was charged into a 1 L beaker, and the previous reaction solution was added dropwise little by little. The precipitate was filtered off and washed by sprinkling with 500 parts of water. The obtained wet cake was returned to 500 parts of water and slurried at room temperature for 30 minutes, and then filtered off. Thereafter, it was washed by sprinkling with 500 parts of water. The obtained wet cake was dried at 80 °C overnight to obtain ultraviolet absorber (B4).

[0107] <Ultraviolet absorber (B5)> In a 200 mL Erlenmeyer flask, 100 parts of N-methyl-2-pyrrolidone and 40.0 mmol of 2-methacryloyloxyethyl succinic acid (Light Ester HO-MS(N), manufactured by Kyoeisha Chemical Co., Ltd.) were charged, and the mixture was stirred while cooling with ice. 40 mmol of thionyl chloride was added dropwise, and the mixture was stirred for 2 hours while cooling with ice. Then, 20.0 mmol of ultraviolet absorber (B1) was charged, and the mixture was stirred at room temperature for 4 hours. On the other hand, 500 parts of water was charged into a 1 L beaker, and the previous reaction solution was added dropwise little by little. The precipitate was filtered off and washed by sprinkling with 500 parts of water. The obtained wet cake was returned to 500 parts of water, reslurried at room temperature for 30 minutes, and then filtered off. Thereafter, it was washed by sprinkling with 500 parts of water. The obtained wet cake was dried at 80 °C overnight to obtain ultraviolet absorber (B5).

[0108] <Ultraviolet absorber (B6)> In the production of ultraviolet absorber (B5), ultraviolet absorber (B6) was obtained in the same manner except that ω-carboxy-polycaprolactone (n≈2) monoacrylate (Aronix M-5300, manufactured by Toagosei Co., Ltd.) was added instead of 2-methacryloyloxyethyl succinic acid (Light Ester HO-MS(N), manufactured by Kyoeisha Chemical Co., Ltd.).

[0109] <Ultraviolet absorber (B7)> In the production of ultraviolet absorber (B5), ultraviolet absorber (B7) was obtained in the same manner except that mono-hydroxyethyl acrylate phthalate (Aronix M-5400, manufactured by Toagosei Co., Ltd.) was added instead of 2-methacryloyloxyethyl succinic acid (Light Ester HO-MS(N), manufactured by Kyoeisha Chemical Co., Ltd.).

[0110] <Ultraviolet absorber (B8)> In a 300 mL Erlenmeyer flask, 170 parts of chlorobenzene, 43.4 mmol of 2-chloro-4,6-di(naphthalen-1-yl)-1,3,5-triazine, and 65.1 mmol of aluminum chloride were charged and stirred to form a suspension. Next, while cooling with ice water, 65.1 mmol of 2-naphthol was added little by little. Then, the mixture was stirred overnight while gradually returning to room temperature. On the other hand, 38.1 parts of water, 10.0 parts of 35% hydrochloric acid, and 45.0 parts of methanol were charged into a 500 mL beaker, and the previous reaction solution was added dropwise little by little. Further, 45.0 parts of methanol was added to the Erlenmeyer flask in multiple portions while washing and added to the 500 mL beaker. The precipitate was filtered off and washed by sprinkling with a mixed solvent of water / methanol = 75 parts / 75 parts. The obtained wet cake was returned to 150 parts of water and slurried at room temperature for 30 minutes, and then filtered off. Thereafter, it was washed by sprinkling with 150 parts of water. The obtained wet cake was dried at 80 °C overnight to obtain an ultraviolet absorber (B8).

[0111] <Ultraviolet absorber (B9)> In a 300 mL Erlenmeyer flask, 170 parts of chlorobenzene, 43.4 mmol of 2,4-dichloro-6-phenyl-1,3,5-triazine, and 65.1 mmol of aluminum chloride were charged and stirred to form a suspension. Next, while cooling with ice water, 108.5 mmol of 2-naphthol was added little by little. Then, the mixture was stirred overnight while gradually returning to room temperature. On the other hand, 38.1 parts of water, 10.0 parts of 35% hydrochloric acid, and 45.0 parts of methanol were charged into a 500 mL beaker, and the previous reaction solution was added dropwise little by little. Further, 45.0 parts of methanol was added to the Erlenmeyer flask in multiple portions while washing and added to the 500 mL beaker. The precipitate was filtered off and washed by sprinkling with a mixed solvent of water / methanol = 75 parts / 75 parts. The obtained wet cake was returned to 150 parts of water and slurried at room temperature for 30 minutes, and then filtered off. Thereafter, it was washed by sprinkling with 150 parts of water. The obtained wet cake was dried at 80 °C overnight to obtain an ultraviolet absorber (B9).

[0112] <Ultraviolet absorber (B10-1)> In the production of the ultraviolet absorber (B8), the ultraviolet absorber (B10-1) was obtained in the same manner except that 2-chloro-4,6-diphenyl-1,3,5-triazine was added instead of 2-chloro-4,6-di(naphthalen-1-yl)-1,3,5-triazine.

[0113] <Ultraviolet absorber (B10-2)> 420 mmol of methyl 2-hydroxy-1-naphthoate was charged into a 500 mL Erlenmeyer flask and heated to 90 °C with stirring. Next, 128 mmol of benzamidine hydrochloride and 26 parts of a 30% solution of sodium methylate were charged and stirred at 90 °C for 22 hours. Thereafter, 200 parts of methanol was charged, cooled to room temperature, and filtered. The obtained wet cake was returned to 150 parts of methanol and slurried at room temperature for 30 minutes, then filtered off. Thereafter, it was washed by sprinkling with 150 parts of methanol. The obtained wet cake was dried at 80 °C overnight to obtain the ultraviolet absorber (B10-2). The ultraviolet absorber (B10-2) is the same compound synthesized by a synthetic route different from that of the ultraviolet absorber (B10-1).

[0114] <Ultraviolet absorber (B11)>: Tinvin477 manufactured by BASF <Ultraviolet absorber (B12)>: Tinvin460 manufactured by BASF <Ultraviolet absorber (B13)>: LA-F70 manufactured by ADEKA <Ultraviolet absorber (B'1)>: Tinvin400 manufactured by BASF

[0115] <Measurement of absorbance of ultraviolet absorber (B)> The absorbance of the ultraviolet absorber (B) was measured as follows.

[0116] <Solution preparation method> 1 part of the ultraviolet absorber (B1) and 1000 parts of tetrahydrofuran were mixed and completely dissolved. Subsequently, 1 part of the previous solution and 99 parts of tetrahydrofuran were uniformly mixed to prepare a solution with a concentration of 10 ppm.

[0117] <Measurement conditions> Apparatus: U-3500 (manufactured by Hitachi, Ltd.) Measuring wavelength: 260 - 700 nm Solvent: Tetrahydrofuran Concentration: As described in Table 1

[0118] The evaluation criteria for ultraviolet - visible absorption spectra are as follows. ◎: Absorbance at wavelengths of 400 - 420 nm is 0.3 or more over the entire region 〇: Absorbance at wavelengths of 400 - 420 nm is 0.1 or more over the entire region △: Absorbance at wavelengths of 400 - 420 nm is 0.1 or more in part and less than 0.1 in the other part ×: Absorbance at wavelengths of 400 - 420 nm is more than 0 and less than 0.1 over the entire region ××: Absorbance at wavelengths of 400 - 420 nm is 0 over the entire region

[0119]

Table 1

[0120] As shown in Table 1, it was found that the ultraviolet absorber of the present invention has a higher absorbance per unit weight in the short - wavelength visible light region of 400 - 420 nm compared with conventional ultraviolet absorbers.

[0121] (B11) Tinuvin 477 (manufactured by BASF Japan Ltd.), (B12) Tinuvin 460 (manufactured by BASF Japan Ltd.), (B13) LA - F70 (manufactured by ADEKA Corp.), (B’1) Tinuvin 400 (manufactured by BASF Japan Ltd.) are triazine - type ultraviolet absorbers but do not have naphthalene rings respectively. The absorbance of (B11), (B12), (B13) at wavelengths of 400 - 420 nm is more than 0 and less than 0.1 over the entire region, and the absorbance of (B’1) at wavelengths of 400 - 420 nm is 0 over the entire region.

[0122] The raw materials used in the synthesis examples, examples, and comparative examples are described in Tables 2, 3, and 4 for the formulation and composition of the synthesis examples.

[0123] <Weight-average molecular weight (Mw)> The weight-average molecular weight was measured as the polystyrene-equivalent weight-average molecular weight using gel permeation chromatography "HLC-8220GPC" manufactured by Tosoh Corporation, with the separation columns: "TSK-GEL SUPER H5000", "TSK-GEL SUPER H4000", "TSK-GEL SUPER H3000", and "TSK-GEL SUPER H2000" manufactured by Tosoh Corporation connected in series, and tetrahydrofuran at a temperature of 40 °C as the mobile phase, at a flow rate of 0.6 ml / min.

[0124] <Production of urethane acrylate compound (a1x-1) (1)> (Synthesis Example 1): Urethane acrylate mixture (A1): In a four-necked flask equipped with a stirrer, reflux condenser, nitrogen inlet tube, thermometer, and dropping funnel, 1049.0 parts by mass of dipentaerythritol pentaacrylate (a4) purchased from Molekula and 0.1 part by mass of Neostan U-810 (tin catalyst manufactured by Nitto Kasei Co., Ltd.) were placed, and after raising the liquid temperature to 50 °C, 223.2 parts by mass of VESTANAT IPDI (isophorone diisocyanate manufactured by Evonik) was added dropwise from the dropping funnel over 30 minutes. After the temperature rise subsided, the temperature was raised to 80 °C and reacted for 3 hours. After confirming that the peak of the isocyanate group disappeared by Fourier transform infrared spectroscopy (FT-IR), the temperature was lowered to room temperature, and a urethane acrylate mixture (A1) with 100.0% by mass of non-volatile content containing 99.9% by mass of urethane acrylate compound (a1x-1) having 10 acryloyl groups with a weight-average molecular weight of 1300 in the non-volatile content was obtained.

[0125] <Production of urethane acrylate compound (a1x-2) and compound (a1x-3)> (Synthesis Example 2) and (Synthesis Example 3): Urethane acrylate mixtures (A2) and (A3): In the same manner as in (Synthesis Example 1), according to the formulations in Table 3, urethane acrylate mixtures (A2) and (A3) containing urethane acrylate compound (a1x-2) and compound (a1x-3) were obtained.

[0126] <Production of urethane acrylate compound (a1x-4)> (Synthesis Example 4): Urethane acrylate mixture (A4): Into a four-necked flask equipped with a stirrer, reflux condenser, nitrogen inlet tube, thermometer, and dropping funnel, 2455.4 parts by mass of VESTANAT IPDI, 1442.1 parts by mass of CHDM (manufactured by SK Chemicals, cyclohexyl dimethanol), and 0.1 part by mass of Neostan U-810 were placed. The temperature was raised to 80°C and reacted for 3 hours. After confirming by FT-IR that the peak intensity of the isocyanate group became 50% of that before the reaction, 596.5 parts by mass of PE-3A (manufactured by Thermo F.S., pentaerythritol triacrylate) was added, and further reacted at 80°C for 3 hours. After confirming by FT-IR that the peak of the isocyanate group disappeared, the temperature was lowered to room temperature, and a urethane acrylate mixture (A4) with a non-volatile content of 100.0% by mass containing 99.8% by mass of a urethane acrylate compound (a1x-4) having 6 acryloyl groups and a weight average molecular weight of 4500 in the non-volatile matter was obtained.

[0127] <Production of urethane acrylates (a1x-5) to (a1x-7), (a1y-1), and (Ax1-8) to (Ax1-12)> (Synthesis Examples 5) to (Synthesis Example 8), and (Synthesis Examples 10) to (Synthesis Example 14): In the same manner as in (Synthesis Example 4), according to the formulations in Tables 3 and 4, urethane acrylate mixtures (A5) to (A8), and mixtures (A10) to (A14) containing urethane acrylate compounds (a1x1-5) to (a1x-7), compound (a1y-1), and compounds (a1x-8) to (a1x-12) were obtained.

[0128] <Production of urethane acrylate compound (a1y-2)> (Synthesis Example 9): Urethane acrylate mixture (A9): In a four-necked flask equipped with a stirrer, reflux condenser, nitrogen inlet tube, thermometer, and dropping funnel, 432.5 parts by mass of 4-HBA (4-hydroxybutyl acrylate manufactured by Mitsubishi Chemical Corporation) and 0.1 part by mass of Neo-Stann U-810 (tin catalyst manufactured by Nitto Kasei Co., Ltd.) were placed. After adjusting the liquid temperature to 50 °C, 545.7 parts by mass of DURANATE TPA-100 (hexamethylene diisocyanate trimer manufactured by Asahi Kasei Corporation) was added dropwise from the dropping funnel over 30 minutes. After the temperature rise subsided, the temperature was raised to 80 °C and the reaction was carried out for 3 hours. After confirming that the peak of the isocyanate group disappeared by Fourier transform infrared spectroscopy (FT-IR), the temperature was lowered to room temperature, and a urethane acrylate mixture (A9) with a non-volatile content of 100.0% by mass, containing 95.8% by mass of a urethane acrylate compound (a1y-2) having three acryloyl groups with a weight average molecular weight of 950, was obtained.

[0129] As the polyacrylate mixture (A15), Aronix M-315 (a mixture of 92% by mass of EO-modified triacrylate of isocyanuric acid (a1y-3) and 8% by mass of EO-modified diacrylate of isocyanuric acid (a3) manufactured by Toagosei Co., Ltd.) was used.

[0130] As the polyacrylate mixture (A16), Aronix M-405 (a mixture of 85% by mass of dipentaerythritol hexaacrylate (a2-1) and 15% by mass of dipentaerythritol pentaacrylate (a2-2) manufactured by Toagosei Co., Ltd.) was used.

[0131] [Table 2]

[0132] [Table 3]

[0133] [Table 4]

[0134] (Example 1): 100.07 parts by mass of a urethane acrylate mixture (A1), 10 parts by mass of an ultraviolet absorber (B3), and 10 parts by mass of Irgacure OXE01 (manufactured by BASF, a photoinitiator) were added to a flask equipped with a stirrer and stirred and mixed. Then, 51.46 parts by mass of propylene glycol monomethyl ether (PGME) was further added and stirred and mixed to prepare a composition for forming a hard coat layer having a nonvolatile content of 70% by mass.

[0135] (Examples 2) to (Example 43), and (Comparative Example 1) to (Comparative Example 7): In the same manner as in (Example 1), a composition for forming a hard coat layer having a nonvolatile content of 70% by mass was prepared, and the results shown in Tables 5 to 8 were obtained.

[0136] The materials used in the examples and comparative examples are described below.

[0137] ·Mixture (A1): A urethane acrylate mixture with a nonvolatile content of 100% by mass containing 99.93% by mass of compound (a1x-1) ·Mixture (A2): A urethane acrylate mixture with a nonvolatile content of 83.98% by mass containing 81.35% by mass of compound (a1x-2) ·Mixture (A3): A urethane acrylate mixture with a nonvolatile content of 100% by mass containing 99.89% by mass of compound (a1x-3) ·Mixture (A4): A urethane acrylate mixture with a nonvolatile content of 100% by mass containing 99.77% by mass of compound (a1x-4) ·Mixture (A5): A urethane acrylate mixture with a nonvolatile content of 100% by mass containing 99.79% by mass of compound (a1x-5) ·Mixture (A6): A urethane acrylate mixture with a nonvolatile content of 100% by mass containing 99.92% by mass of compound (a1x-6) ·Mixture (A7): A urethane acrylate mixture with a nonvolatile content of 100% by mass containing 99.92% by mass of compound (a1x-7) ·Mixture (A8): A urethane acrylate mixture with a nonvolatile content of 100% by mass containing 99.92% by mass of compound (a1y-1) · Mixture (A9): A urethane acrylate mixture with 100% by mass of non-volatile matter containing 95.79% by mass of compound (a1y-2) · Mixture (A10): A urethane acrylate mixture with 100% by mass of non-volatile matter containing 95.89% by mass of compound (a1x-8) · Mixture (A11): A urethane acrylate mixture with 100% by mass of non-volatile matter containing 95.92% by mass of compound (a1x-9) · Mixture (A12): A urethane acrylate mixture with 100% by mass of non-volatile matter containing 95.93% by mass of compound (a1x-10) · Mixture (A13): A urethane acrylate mixture with 100% by mass of non-volatile matter containing 95.93% by mass of compound (a1x-11) · Mixture (A14): A urethane acrylate mixture with 100% by mass of non-volatile matter containing 95.91% by mass of compound (a1x-12) · As mixture (A15), Aronix M-315 (manufactured by Toagosei Co., Ltd., a mixture of 92% by mass of EO-modified isocyanuric acid triacrylate (a1y-3) and 8% by mass of EO-modified isocyanuric acid diacrylate (a3)) was used.

[0138] · As mixture (A16), Aronix M-405 (manufactured by Toagosei Co., Ltd., a mixture of 85% by mass of dipentaerythritol hexaacrylate (a2-1) and 15% by mass of dipentaerythritol pentaacrylate (a2-2)) was used.

[0139] <A polyfunctional urethane (meth)acrylate compound (a1x) having 4 to 15 (meth)acryloyl groups and a weight average molecular weight of 500 to 15,000> · Compound (a1x-1): Weight average molecular weight 1300, number of acryloyl groups 10, acryloril group equivalent 130, urethane acrylate (having an isophorone ring) · Compound (a1x-2): Weight average molecular weight 1600, number of acryloyl groups 9, acryloril group equivalent 178, urethane acrylate (having an isophorone ring and a nurate ring) · Compound (a1x-3): Weight-average molecular weight 800, number of acryloyl groups 6, acryloyl group equivalent 133, urethane acrylate (having an isophorone ring) · Compound (a1x-4): Weight-average molecular weight 4500, number of acryloyl groups 6, acryloyl group equivalent 750, urethane acrylate (having an isophorone ring and a cyclohexyl ring) · Compound (a1x-5): Weight-average molecular weight 5000, number of acryloyl groups 10, acryloyl group equivalent 500, urethane acrylate (having an isophorone ring and a cyclohexyl ring) · Compound (a1x-6): Weight-average molecular weight 10000, number of acryloyl groups 10, acryloyl group equivalent 1000, urethane acrylate (having a polycarbonate chain having an isophorone ring and a cyclohexyl ring) · Compound (a1x-7): Weight-average molecular weight 15000, number of acryloyl groups 10, acryloyl group equivalent 1500, urethane acrylate (having a polycarbonate chain having an isophorone ring and a cyclohexyl ring) · Compound (a1x-8): Weight-average molecular weight 1600, number of acryloyl groups 10, acryloyl group equivalent 160, urethane acrylate (having an isophorone ring and a cyclohexyl ring) · Compound (a1x-9): Weight-average molecular weight 2400, number of acryloyl groups 10, acryloyl group equivalent 240, urethane acrylate (having a polycarbonate chain having an isophorone ring and a cyclohexyl ring) · Compound (a1x-10): Weight-average molecular weight 2500, number of acryloyl groups 10, acryloyl group equivalent 250, urethane acrylate (having an isophorone ring and an aliphatic polyester chain) · Compound (a1x-11): Weight-average molecular weight 2500, number of acryloyl groups 10, acryloyl group equivalent 250, urethane acrylate (having an isophorone ring and an aliphatic polyether chain) · Compound (a1x-12): Weight-average molecular weight 3200, number of acryloyl groups 15, acryloyl group equivalent 213, urethane acrylate (having an isophorone ring and an aliphatic polyether chain)

[0140] <A compound (a1y) having three or more (meth)acryloyl groups other than the compound (a1x) and having a (meth)acryloyl group equivalent of 115 or more> · Compound (a1y-1): Weight average molecular weight 18,000, number of acryloyl groups 10, acryloyl group equivalent 1800, urethane acrylate (having a polycarbonate chain having an isophorone ring and a cyclohexyl ring) · Compound (a1y-2): Weight average molecular weight 950, number of acryloyl groups 3, acryloyl group equivalent 317, urethane acrylate (having a nurate ring) · Compound (a1y-3): Weight average molecular weight 423, number of acryloyl groups 3, acryloyl group equivalent 141, EO-modified triacrylate of isocyanuric acid (having a nurate ring)

[0141] <A polyacrylate compound (a2) other than the compound (a1) and a compound (a3)> · (a3) Weight average molecular weight 369, number of acryloyl groups 2, acryloyl group equivalent 185, EO-modified diacrylate of isocyanuric acid (having a nurate ring) · (a2-1) Weight average molecular weight 579, number of acryloyl groups 6, acryloyl group equivalent 96, dipentaerythritol hexaacrylate · (a2-2) Weight average molecular weight 524, number of acryloyl groups 5, acryloyl group equivalent 105, dipentaerythritol pentaacrylate

[0142] <A photopolymerization initiator (C)> · Photopolymerization initiator (C1-1): Irugacure OXE01 manufactured by BASF, oxime ester type · Photopolymerization initiator (C1-2): Irugacure OXE03 manufactured by BASF, oxime ester type · Photopolymerization initiator (C1-3): Adeka Cure NCI-831 manufactured by ADEKA, oxime ester type · Photopolymerization initiator (C2-1): Ormnirad TPOH manufactured by IGM Resins, phosphine oxide type · Photoinitiator (C3-1): Omnirad 184 manufactured by IGM Resins, acetophenone-based · Photoinitiator (C3-2): ESCURE ONE manufactured by IGM Resins <Volatile matter (organic solvent)> · Butyl acetate: Organic solvent derived from the polyisocyanate used in Synthesis Example 2 of (a1x-2) · Propylene glycol monomethyl ether (PGME): Organic solvent for adjusting the non-volatile content of the hard coat layer-forming composition.

[0143] <Manufacture of laminate with hard coat layer> The above ultraviolet curable composition was applied to a polyethylene terephthalate substrate with a thickness of 50 μm using a bar coater so that the dry film thickness was 5 μm. After drying the obtained coating layer at 100 °C for 1 minute, it was irradiated with ultraviolet rays of 400 mJ / cm 2 and cured to produce a laminate provided with a hard coat layer.

[0144] The transmittance at 410 nm and 450 nm, b * value, elastic modulus, and warp (curling property) of the laminate provided with the hard coat layer prepared above were measured.

[0145] [Measurement of transmittance] The transmittance at 410 nm and 450 nm of the laminate provided with the hard coat layer prepared above was measured using a Hitachi High-Technologies Corporation spectrophotometer "U-4100" installed in a thermo-hygrostat chamber at 23 °C and a relative humidity of 50% (hereinafter 50% RH). [Level classification of transmittance at 410 nm] · 3: Less than 3.3% · 2: 3 - 5% · 1: More than 5% [Level classification of transmittance at 450 nm] · 3: 75% or more · 2: 70% or more and less than 75% · 1: Less than 70%

[0146] [Measurement of b * ​The laminate with the above-prepared hard coat layer was placed in a thermo-hygrostat chamber at 23°C and 50% RH, and the average measurement value at n = 3 under a D65 light source was measured using a spectro-colorimeter "SH 7000" manufactured by Nippon Denshoku Industries Co., Ltd. as b * and used as such. [Classification by level of b * · 3:15 or less · Exceeding 2:15 and 20 or less · Exceeding 1:20

[0147] [Measurement of elastic modulus] For the hard coat layer of the laminate with the above-prepared hard coat layer, the elastic modulus at a penetration depth of 200 nm was measured using a nanoindenter under the following conditions.

[0148] Nanoindenter: "TI Premier" manufactured by Bruker Indenter: Berkovich (triangular pyramid type) Measurement mode: Single penetration Measurement temperature: Room temperature (25°C) Penetration depth: 200 nm Loading (unloading) rate: 40 nm / s Holding time: 2 s

[0149] [Measurement of warp] The laminate with the above-prepared hard coat layer was cut into a test film with a length of 100 mm × a width of 50 mm and left in a thermo-hygrostat chamber at 23°C and 50% RH for 6 hours. The test film was placed on a horizontal plane, and the distance between both ends in the width direction was measured at three locations at both ends and the center of the long side using a micro-gauge, and the average value was calculated. [Classification by level of warp] 4:49 mm or more 3:47 mm or more and less than 49 mm 2:45 mm or more and less than 47 mm 1: Less than 45 mm

[0150] The haze value, abrasion resistance, pencil hardness, elution resistance, and light resistance of the laminate provided with the above-prepared hard coat layer were evaluated by the following methods.

[0151] [HZ[%]; Evaluation of haze value] The laminate provided with the above-prepared hard coat layer was placed in a thermo-hygrostat chamber at 23°C and 50% RH, and the measured average value of n = 3 under a D65 light source was taken as the haze value (HZ) using a "Haze Meter SH7000" manufactured by Nippon Denshoku Industries Co., Ltd. If it is less than 1.0%, there is no practical problem. [Evaluation criteria] ·3: Less than 0.8%: Very good ·2: 0.8 - 1.0%: No practical problem ·1: Exceeding 1.0%: Not practical

[0152] [Evaluation of abrasion resistance] The abrasion resistance of the laminate provided with the above-prepared hard coat layer was evaluated using a "Gakushin-type friction fastness tester" manufactured by Tester Sangyo Co., Ltd. A friction pad (surface area 1 cm 2 ) with a load of 1000 g attached was fitted with steel wool #0000, and the surface of the hard coat layer (1 cm × 15 cm) was reciprocated 10 times. Then, the number of scratches on the surface of the hard coat layer was counted and evaluated according to the following criteria. The fewer the number of scratches, the better, and if it is 3 or less, it can be used without practical problems. [Evaluation criteria] ·3: No scratches (0): Very good ·2: 1 - 3 scratches: No practical problem ·1: 4 or more scratches: Not practical

[0153] [Evaluation of pencil hardness] The laminate provided with the above-prepared hard coat layer was measured using pencils of different hardnesses according to the test method conforming to JIS K5400 (1990). If the pencil hardness is "H" or higher, there is no practical problem.

[0154] [Evaluation of elution resistance] The laminate provided with the above-prepared hard coat layer was cut into a test film with a length of 100 mm × a width of 50 mm to obtain a test film. The test film was immersed in a 9 mass% sodium hydroxide aqueous solution heated to 50°C for 5 minutes, and the taken-out test film was washed with water and dried in a box oven at 100°C for 2 minutes. Using a Hitachi High-Technologies Corporation spectrophotometer "U-4100", the transmittances (ta) and (tc) shown below were measured. (ta): Transmittance of the hard coat film not immersed in the sodium hydroxide aqueous solution at a wavelength of 380 nm (tc): Transmittance of the hard coat film at a wavelength of 380 nm after being immersed in the sodium hydroxide aqueous solution, washed with water, and dried From the obtained (ta) and (tc), the change amount of transmittance ((tc) - (ta)) was calculated, and the elution resistance was evaluated according to the following criteria. In Comparative Example 2 not containing the ultraviolet absorber (B), the elution resistance evaluation was not possible and was denoted as "-". [Evaluation Criteria] 3: Change amount of transmittance is 1% or less: Good 2: Change amount of transmittance exceeds 1% and is 2% or less: No problem in practical use 1: Change amount of transmittance exceeds 2%: Not practical

[0155] [Evaluation of Light Resistance] The laminate provided with the hard coat layer prepared above was exposed for 100 hours with a xenon weather meter at an illuminance of 60 W / m² for wavelengths of 300 to 400 nm. 2 After that, using a Hitachi High-Technologies Corporation spectrophotometer "U-4100", the absorbances Aa and Ac at the maximum absorption wavelength shown below were measured, and the decrease rate of absorbance was calculated from the following formula. Decrease rate of absorbance (%) = {(Aa - Ac) / Aa} × 100 Aa: Before evaluation with the xenon weather meter Ac: After 100 hours of exposure with the xenon weather meter [Evaluation Criteria] 3: Decrease rate of absorbance at the maximum absorption wavelength is less than 5%: Good 2: Decrease rate of absorbance at the maximum absorption wavelength is 5% or more and less than 20%: No problem in practical use 1: Decrease rate of absorbance at the maximum absorption wavelength is 20% or more: Not practical

[0156]

Table 5

[0157]

Table 6

[0158]

Table 7

[0159]

Table 8

Claims

1. A laminate having a hard coat layer on a transparent substrate, wherein the hard coat layer is a cured product of an ultraviolet curable composition containing a polymerizable compound (A), an ultraviolet absorber (B), and a photopolymerization initiator (C), the polymerizable compound (A) contains a compound (a1) having three or more (meth)acryloyl groups and a (meth)acryloyl group equivalent of 115 or more, the ultraviolet absorber (B) is a triazine compound that absorbs light having a wavelength of 400 to 420 nm, the photopolymerization initiator (C) contains at least one of an oxime ester compound (C1) and a phosphine oxide compound (C2), A laminate characterized by satisfying all of the following (1) to (5) in a configuration having a hard coat layer with a thickness of 5 μm on a polyethylene terephthalate substrate. (1) The spectral transmittance of light having a wavelength of 410 nm is 5% or less (2) The spectral transmittance of light having a wavelength of 450 nm is 70% or more (3) b ＊ value is 20 or less (4) The elastic modulus of the hard coat layer is 3.0 GPa or more (5) After leaving in a high-temperature and high-humidity chamber at 23°C and a relative humidity of 50% for 6 hours, the distance between both ends in the width direction of the long side of a test film having a length of 100 mm × a width of 50 mm is 45 mm or more

2. The laminate according to claim 1, wherein the compound (a1) contains a polyfunctional urethane (meth)acrylate (a1x) having 4 to 15 (meth)acryloyl groups and a weight average molecular weight of 500 to 15,000.

3. The laminate according to claim 1 or 2, wherein the ultraviolet absorber (B) has 1 to 3 naphthalene rings directly bonded to the triazine ring, and at least one of the naphthalene rings has a hydroxyl group at the 2-position.

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