JP7273252B2 - Laminate and its manufacturing method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a laminate having improved coating film adhesion after an environmental test, and a method for producing the same.

Conventionally, a resin film laminate having a coating layer (hereinafter also referred to as "surface layer") has been used in various fields (see Patent Document 1). For example, such a laminate of resin films is used in front panels and rear panels of mobile devices, interior parts of automobiles, and the like.

Japanese Patent Publication No. 2017-508828

A surface layer that protects the surface of a laminate of resin films is required to have a certain degree of hardness and high scratch resistance. On the other hand, in order to produce a laminate having a desired shape, the resin film forming each layer is required to have excellent moldability. Moreover, it has been difficult to satisfy all of these different performances in the resin composition used for the production of the surface layer of the laminate in particular.

Therefore, the present invention provides a laminate that can produce a hard coat layer having excellent scratch resistance and high hardness when cured, and has improved coating adhesion after environmental tests, and a method for producing the same. .

The present inventors have made earnest studies to solve the above problems. As a result, at least in the production of a laminate having a substrate layer and a surface layer, by using a plurality of solvents having a predetermined boiling point and under a certain range of drying conditions, the coating film adhesion after the environmental test is improved. found to improve effectively. The present invention has been completed through further studies based on such findings.

（式（Ｉ）中、
ｍは、炭素数１～４のアルキレン基、又は、単結合であり、
ｎは、炭素数１～４のアルキル基、又は、水素であり、
ｐは、単結合、又は、炭素数１又は２のアルキレン基であり、
ｑは、エポキシ基、水酸基、アクリロイル基、及び、メタクリロイル基の少なくともいずれかの置換基を含んでも良い全炭素数が１～１２のアルキル基、又は、水素である。）
＜３＞
前記式（Ｉ）において、
ｍが、炭素数１又は２のアルキレン基であり、
ｎが、炭素数１又は２のアルキル基あり、
ｐが、単結合、又は、メチレン基であり、
ｑが、グリシジル基、水酸基、及び、アクリロイル基の少なくともいずれかの置換基を含んでも良い全炭素数が１～６のアルキル基、又は、水素である、＜２＞に記載の積層体。
＜４＞
前記式（Ｉ）において、ｍはメチレン基であり、ｎはメチル基であり、ｐは単結合であり、ｑは、メチル基、グリシジル基（エポキシ基）を含む炭素数５以下のアルキル基、又は、水酸基とアクリロイル基とを含む炭素数８以下のアルキル基である、＜３＞に記載の積層体。
＜５＞
（メタ）アクリロイルポリマー（Ｃ）が、以下の式（ＩＩ－ａ）、式（ＩＩ－ｂ）、及び、式（ＩＩ－ｃ）で示される繰り返し単位の少なくともいずれかを含む、＜２＞に記載の積層体。

＜６＞
前記式（ＩＩ－ａ）の繰り返し単位、上記式（ＩＩ－ｂ）の繰り返し単位、及び、前記式（ＩＩ－ｃ）の繰り返し単位の合計モル数を基準として、前記式（ＩＩ－ａ）の繰り返し単位は、３０～８５モル％であり、前記式（ＩＩ－ｂ）の繰り返し単位は、５～３０モル％であり、前記式（ＩＩ－ｃ）の繰り返し単位は、１０～４０モル％である、＜５＞に記載の積層体。
＜７＞
前記式（ＩＩ－ａ）の繰り返し単位と、前記式（ＩＩ－ｂ）の繰り返し単位と、前記式（ＩＩ－ｃ）の繰り返し単位とのモル比が、４．５～５．５：１．５～２．５：２．５～３．５である、＜５＞に記載の積層体。
＜８＞
（メタ）アクリロイルポリマー（Ｃ）が、ペンタエリスリトール系多官能性アクリレート化合物をさらに含む、＜１＞～＜７＞のいずれかに記載の積層体。
＜９＞
前記ペンタエリスリトール系多官能性アクリレート化合物が、以下の式（ＩＩＩ－ａ）で示されるペンタエリスリトールテトラアクリレート、及び、式（ＩＩＩ－ｂ）で示されるジペンタエリスリトールヘキサアクリレート、及び、ペンタエリスリトールトリアクリレートからなる群より選択される１以上である、＜８＞に記載の積層体。

＜１０＞
前記ペンタエリスリトール系多官能性アクリレート化合物が、前記樹脂組成物の総質量を基準として、７０質量％以下の量で含まれる、＜８＞又は＜９＞に記載の積層体。
＜１１＞
前記樹脂組成物が、放射線硬化性である、＜１＞～＜１０＞のいずれかに記載の積層体。
＜１２＞
前記樹脂組成物が、光重合開始剤をさらに含む、＜１＞～＜１１＞のいずれかに記載の積層体。
＜１３＞
前記基材層が、熱可塑性樹脂を含む、＜１＞～＜１２＞のいずれかに記載の積層体。
＜１４＞
加飾シートである、＜１＞～＜１３＞のいずれかに記載の積層体。
＜１５＞
＜１＞～＜１４＞のいずれかに記載の積層体を熱成形した成形体。
＜１６＞
＜１＞～＜１５＞のいずれかに記載の積層体を製造する方法であって、前記方法が、
放射線硬化性樹脂と有機溶剤とを含有する樹脂組成物を基材層の表面に塗工し塗工物を得る工程１と、
得られた塗工物を乾燥させて、前記基材層の表面に表面層を形成する工程２
と含み、
前記積層体は、少なくとも、基材層と表面層とを備え、
前記樹脂組成物は、沸点が１２０℃未満の有機溶剤（Ａ）、及び沸点が１２０℃以上の有機溶剤（Ｂ）を質量比で、Ａ：Ｂ＝３：７～７：３の範囲で含有し、
前記樹脂組成物は、（メタ）アクリロイルポリマー（Ｃ）を含み、前記（メタ）アクリロイルポリマー（Ｃ）は２００～６００ｇ／ｅｑの（メタ）アクリル等量と５，０００～２００，０００の質量平均分子量を有し、
前記表面層の塗膜密着性は、ＪＩＳ Ｋ ５６００－５－６の評価方法によって定められる評価結果が０である、方法。
＜１７＞
前記工程２において、少なくとも２つの乾燥炉が使用され、最後の乾燥炉における乾燥炉温度は最初の乾燥炉における乾燥炉温度よりも高い、＜１６＞に記載の方法。
＜１８＞
前記工程２において、塗工物を６０℃以上に加温可能な乾燥炉が少なくとも２つ使用され、
第１の乾燥炉における乾燥炉温度が９０～１２０℃の範囲であり、第２の乾燥炉おける乾燥炉温度が１００～１４０℃の範囲である、＜１６＞又は＜１７＞に記載の方法。
＜１９＞
前記基材層の厚さが、０．１ｍｍ～１．０ｍｍであり、前記基材層の表面に塗工した樹脂組成物の層の厚さが、１．０μｍ～１０μｍである、＜１６＞～＜１８＞のいずれかに記載の方法。That is, the present invention includes the following aspects.
<1>
A laminate comprising at least a substrate layer and a surface layer provided on the surface of the substrate layer,
The surface layer contained an organic solvent (A) with a boiling point of less than 120°C and an organic solvent (B) with a boiling point of 120°C or higher in a mass ratio of A:B = 3:7 to 7:3. By coating the resin composition, drying at least in a first drying oven at a temperature in the range of 90 to 120 ° C., and then drying in a second drying oven at a temperature in the range of 100 to 140 ° C. is formed and
The resin composition contains a (meth)acryloyl polymer (C), and the (meth)acryloyl polymer (C) has a (meth)acrylic equivalent weight of 200 to 600 g/eq and a weight average of 5,000 to 200,000. has a molecular weight,
The laminate, wherein the coating film adhesion of the surface layer is 0 as an evaluation result determined by the evaluation method of JIS K 5600-5-6.
<2>
The laminate according to <1>, wherein the (meth)acryloyl polymer (C) contains a repeating unit represented by the following formula (I).

(In formula (I),
m is an alkylene group having 1 to 4 carbon atoms or a single bond,
n is an alkyl group having 1 to 4 carbon atoms or hydrogen,
p is a single bond or an alkylene group having 1 or 2 carbon atoms,
q is an alkyl group having 1 to 12 carbon atoms in total, which may contain at least one substituent of an epoxy group, a hydroxyl group, an acryloyl group, and a methacryloyl group, or hydrogen. )
<3>
In the formula (I),
m is an alkylene group having 1 or 2 carbon atoms,
n is an alkyl group having 1 or 2 carbon atoms,
p is a single bond or a methylene group,
The laminate according to <2>, wherein q is an alkyl group having a total of 1 to 6 carbon atoms which may contain at least one substituent of a glycidyl group, a hydroxyl group, and an acryloyl group, or hydrogen.
<4>
In the formula (I), m is a methylene group, n is a methyl group, p is a single bond, q is a methyl group, an alkyl group having 5 or less carbon atoms including a glycidyl group (epoxy group), Alternatively, the laminate according to <3>, which is an alkyl group having 8 or less carbon atoms containing a hydroxyl group and an acryloyl group.
<5>
<2>, wherein the (meth)acryloyl polymer (C) contains at least one of repeating units represented by the following formulas (II-a), (II-b), and (II-c) Laminate as described.

<6>
Based on the total number of moles of the repeating unit of the formula (II-a), the repeating unit of the formula (II-b), and the repeating unit of the formula (II-c), the formula (II-a) The repeating unit is 30 to 85 mol%, the repeating unit of formula (II-b) is 5 to 30 mol%, and the repeating unit of formula (II-c) is 10 to 40 mol%. The laminate according to <5>.
<7>
The molar ratio of the repeating unit of formula (II-a), the repeating unit of formula (II-b), and the repeating unit of formula (II-c) is 4.5 to 5.5:1. 5 to 2.5: The laminate according to <5>, which is 2.5 to 3.5.
<8>
The laminate according to any one of <1> to <7>, wherein the (meth)acryloyl polymer (C) further contains a pentaerythritol-based polyfunctional acrylate compound.
<9>
The pentaerythritol-based polyfunctional acrylate compound is pentaerythritol tetraacrylate represented by the following formula (III-a), and dipentaerythritol hexaacrylate represented by formula (III-b), and pentaerythritol triacrylate. The laminate according to <8>, which is one or more selected from the group consisting of:

<10>
The laminate according to <8> or <9>, wherein the pentaerythritol-based polyfunctional acrylate compound is contained in an amount of 70% by mass or less based on the total mass of the resin composition.
<11>
The laminate according to any one of <1> to <10>, wherein the resin composition is radiation-curable.
<12>
The laminate according to any one of <1> to <11>, wherein the resin composition further contains a photopolymerization initiator.
<13>
The laminate according to any one of <1> to <12>, wherein the base layer contains a thermoplastic resin.
<14>
The laminate according to any one of <1> to <13>, which is a decorative sheet.
<15>
A molded product obtained by thermoforming the laminate according to any one of <1> to <14>.
<16>
A method for producing a laminate according to any one of <1> to <15>, the method comprising:
Step 1 of applying a resin composition containing a radiation-curable resin and an organic solvent to the surface of a substrate layer to obtain a coated product;
Step 2 of drying the obtained coated material to form a surface layer on the surface of the substrate layer
including
The laminate comprises at least a substrate layer and a surface layer,
The resin composition contains an organic solvent (A) with a boiling point of less than 120° C. and an organic solvent (B) with a boiling point of 120° C. or higher in a mass ratio of A:B=3:7 to 7:3. death,
The resin composition contains a (meth)acryloyl polymer (C), and the (meth)acryloyl polymer (C) has a (meth)acrylic equivalent weight of 200 to 600 g/eq and a weight average of 5,000 to 200,000. has a molecular weight,
A method in which the coating film adhesion of the surface layer is 0 as an evaluation result determined by the evaluation method of JIS K 5600-5-6.
<17>
The method according to <16>, wherein in step 2, at least two drying ovens are used, and the drying oven temperature in the last drying oven is higher than the drying oven temperature in the first drying oven.
<18>
In step 2, at least two drying ovens capable of heating the coated material to 60 ° C. or higher are used,
The method according to <16> or <17>, wherein the drying oven temperature in the first drying oven is in the range of 90 to 120°C, and the drying oven temperature in the second drying oven is in the range of 100 to 140°C.
<19>
The base layer has a thickness of 0.1 mm to 1.0 mm, and the resin composition layer applied to the surface of the base layer has a thickness of 1.0 μm to 10 μm, <16> The method according to any one of <18>.

The present invention provides a laminate effectively improved in coating film adhesion after an environmental test without impairing properties required for a laminate for a molded article, such as formability, scratch resistance, hardness, and adhesion. can provide. Since the laminate of the present invention has such excellent characteristics, it is possible to provide a molded article with effectively improved coating film adhesion after an environmental test. Such molded articles are suitable for applications such as automobile interiors and housings for electronic devices. The present invention also provides a method for producing a laminate having effectively improved coating film adhesion after an environmental test, and a molded article obtained from the laminate.

FIG. 1 is a cross-sectional view showing an example of a laminate 10 including a substrate layer 30 and a surface layer 20 provided on the surface of the substrate layer 30. As shown in FIG.

The inventors of the present invention have extensively studied the production of molded articles using laminates, and found that the coating film adhesion of laminates after environmental tests can be effectively improved in some cases. . As a result of repeated trial and error, the inventors of the present invention discovered that the initial drying temperature after coating can be a factor in lowering the adhesion of the coating film, and completed the present invention.

The present invention will be described in detail below. It should be noted that the present invention is not limited to the following embodiments, and can be arbitrarily modified within the scope of the invention's effects.

1. Laminate The structure of the laminate 10 of the present invention is shown, for example, in FIG. That is, the laminate 10 of the present invention includes at least a substrate layer 30 and a surface layer 20 provided on the surface of the substrate layer 30 (FIG. 1). In a preferred embodiment of the invention, the laminate is a molding laminate. The laminate 10 of the present invention may comprise additional layers, such as masking layers, on the surface of the surface layer 20 that is not in contact with the substrate layer 30 . In the embodiment of the present invention, the coating film adhesion of the surface layer 20 in the laminate 10 is 0 as an evaluation result determined by the evaluation method of JIS K 5600-5-6.

In one embodiment of the present invention, a laminate comprising at least a substrate layer and a surface layer provided on the surface of the substrate layer,
The surface layer contained an organic solvent (A) with a boiling point of less than 120°C and an organic solvent (B) with a boiling point of 120°C or higher in a mass ratio of A:B = 3:7 to 7:3. By coating the resin composition, drying at least in a first drying oven at a temperature in the range of 90 to 120 ° C., and then drying in a second drying oven at a temperature in the range of 100 to 140 ° C. is formed and
The resin composition contains a (meth)acryloyl polymer (C), and the (meth)acryloyl polymer (C) has a (meth)acrylic equivalent weight of 200 to 600 g/eq and a weight average of 5,000 to 200,000. has a molecular weight,
A laminate is provided in which the coating film adhesion of the surface layer 20 is evaluated as 0 as determined by the evaluation method of JIS K 5600-5-6.

1.1 Base Layer In the laminate 10 of the present invention, the base layer 30 may be composed of one layer, or may be composed of two or more layers. In one embodiment of the present invention, the substrate layer 30 may be composed of, for example, a first resin layer 31 and a second resin layer 32 (FIG. 1).

In the laminate 10 of the present invention, the base layer 30 contains resin, more preferably thermoplastic resin. The type of thermoplastic resin is not particularly limited, but polycarbonate (PC) resin, acrylic resin such as polymethyl methacrylate (PMMA), polyethylene terephthalate (PET), triacetyl cellulose (TAC), polyethylene naphthalate (PEN), polyimide ( PI), cycloolefin copolymer (COC), norbornene-containing resin, polyether sulfone, cellophane, aromatic polyamide, and other various resins are used. Among these options, the thermoplastic resin of the substrate layer preferably contains at least polycarbonate resin. In a preferred embodiment of the invention, the substrate layer contains a thermoplastic resin.

As the type of polycarbonate resin contained in the substrate layer, -[O-R-OCO]-units (where R is an aliphatic group, an aromatic group, or a combination of an aliphatic group and an aromatic are not particularly limited as long as they contain both groups and further have a linear structure or branched structure, but polycarbonates having a bisphenol skeleton are preferable, and have a bisphenol A skeleton or a bisphenol C skeleton. Polycarbonate is particularly preferred. A mixture or copolymer of bisphenol A and bisphenol C may be used as the polycarbonate resin. By using a bisphenol C-based polycarbonate resin, for example, a polycarbonate resin containing only bisphenol C, or a polycarbonate resin containing a mixture or copolymer of bisphenol C and bisphenol A, the hardness of the substrate layer can be improved.

Also, the viscosity average molecular weight of the polycarbonate resin is preferably 15,000 to 40,000, more preferably 20,000 to 35,000, still more preferably 22,500 to 25,000.

The acrylic resin contained in the base material layer is not particularly limited, but for example, homopolymers of various (meth)acrylic acid esters represented by polymethyl methacrylate (PMMA) and methyl methacrylate (MMA), or PMMA or a copolymer of MMA and one or more other monomers, and a mixture of a plurality of these resins. Among these, a (meth)acrylate containing a cyclic alkyl structure, which is excellent in low birefringence, low hygroscopicity and heat resistance, is preferable. Examples of such (meth)acrylic resins include, but are not limited to, ACRYPET (manufactured by Mitsubishi Rayon Co., Ltd.), Delpet (manufactured by Asahi Kasei Chemicals Corp.), and Parapet (manufactured by Kuraray Co., Ltd.).

It should be noted that it is preferable to use a substrate layer in which the acrylic resin is laminated on the surface layer of a polycarbonate resin, because the hardness of the surface layer of the substrate layer can be improved. In one embodiment of the present invention, the laminate 10 is composed of, for example, a first resin layer 31 and a second resin layer 32 (FIG. 1), and the first resin layer 31 is an acrylic resin layer. and the second resin layer 32 may be a polycarbonate (PC) resin layer. In one such embodiment of the present invention, the surface layer 20 is laminated on the PMMA layer side surface of the substrate layer 30 comprising a polymethyl methacrylate (PMMA) resin layer 31 and a polycarbonate (PC) resin layer 32 . (Fig. 1).

Moreover, the base material layer may contain an additive as a component other than the thermoplastic resin. For example, at least one additive selected from the group consisting of heat stabilizers, antioxidants, flame retardants, flame retardant aids, UV absorbers, release agents and colorants. Antistatic agents, fluorescent whitening agents, antifogging agents, fluidity improvers, plasticizers, dispersants, antibacterial agents, etc. may also be added to the base layer.

The substrate layer preferably contains 80% by mass or more of thermoplastic resin, more preferably 90% by mass or more, and particularly preferably 95% by mass or more of thermoplastic resin. Further, among the thermoplastic resins of the substrate layer, the polycarbonate resin is preferably contained in an amount of 80% by mass or more, more preferably 90% by mass or more, and particularly preferably 95% by mass or more. there is

Although the thickness of the base layer is not particularly limited, it is preferably 0.1 mm to 1.0 mm. The thickness of the base layer is, for example, 0.2 mm to 0.8 mm, or 0.3 mm to 0.7 mm. In a more preferred embodiment of the invention, the substrate layer has a thickness of 0.1 mm to 1.0 mm.

1.2 Surface Layer The surface layer 20 of the present invention is provided by applying a resin composition to the surface of the substrate layer 30 and drying the resin composition. When the substrate layer 30 is composed of a plurality of layers, for example, a first resin layer 31 and a second resin layer 32 (FIG. 1), the surface layer 20 includes the first resin layer 31 and the It is laminated on the surface of the substrate layer 30 provided with the second resin layer 32 on the side of the first resin layer 31 (FIG. 1).

<Resin composition>
The resin composition used for the surface layer of the present invention contains a (meth)acryloyl polymer (C) and an organic solvent.

<(Meth)acryloyl polymer (C)>
In an embodiment of the invention, the (meth)acryloyl polymer (C) has a (meth)acrylic equivalent weight of 200-600 g/eq. The (meth)acrylic equivalent of the (meth)acryloyl polymer is preferably 200 to 500 g/eq, more preferably 220 to 450 g/eq, still more preferably 250 to 400 g/eq.

Also, in an embodiment of the present invention, the (meth)acryloyl polymer (C) has a weight average molecular weight of 5,000 to 200,000. The (meth)acryloyl polymer preferably has a mass average molecular weight of 10,000 to 150,000, more preferably 15,000 to 100,000, and still more preferably 20,000 to 50,000.

The value of the mass average molecular weight can be measured according to paragraphs 0061 to 0064 of JP-A-2007-179018. Details of the measurement method are shown below.

That is, first, a calibration curve showing the relationship between the elution time and the molecular weight of polycarbonate was prepared by a universal calibration method using polystyrene as a standard polymer. Then, the elution curve (chromatogram) of polycarbonate was measured under the same conditions as in the case of the calibration curve described above. Furthermore, the weight average molecular weight (Mw) was calculated from the elution time (molecular weight) of the polycarbonate and the peak area (number of molecules) of the elution time. The weight average molecular weight is represented by the following formula (A), where Ni means the number of molecules with molecular weight Mi.
Mw=Σ(NiMi ² )/Σ(NiMi) (A)

In this specification, (meth)acryl includes both acryl and methacryl.

As described above, for a resin composition containing a (meth)acryloyl polymer (C) having a (meth)acrylic equivalent and a mass average molecular weight within a predetermined range, tack-free property before curing and scratch resistance after curing In addition to having good properties, it is also possible to facilitate curing and polymerization reactions.

In one embodiment of the present invention, the (meth)acryloyl polymer (C) contained in the resin composition used for the surface layer preferably has repeating units represented by the following formula (I).

ただし、式（Ｉ）において、ｍは、炭素数１～４のアルキレン基、又は、単結合であり、ｎは、炭素数１～４のアルキル基、又は、水素であり、ｐは、単結合、又は、炭素数１又は２のアルキレン基であり、ｑは、エポキシ基、水酸基、アクリロイル基、及び、メタクリロイル基の少なくともいずれかの置換基を含んでも良い全炭素数が１～１２のアルキル基、又は、水素である。

However, in formula (I), m is an alkylene group having 1 to 4 carbon atoms or a single bond, n is an alkyl group having 1 to 4 carbon atoms or hydrogen, and p is a single bond. , or an alkylene group having 1 or 2 carbon atoms, and q is an epoxy group, a hydroxyl group, an acryloyl group, and an alkyl group having 1 to 12 carbon atoms in total which may contain at least one substituent of a methacryloyl group , or hydrogen.

In one embodiment of the present invention, the (meth)acryloyl polymer (C) is more preferably the following repeating unit, i.e., in formula (I) above, m is an alkylene group having 1 or 2 carbon atoms, n is an alkyl group having 1 or 2 carbon atoms, p is a single bond or a methylene group, and q is a glycidyl group, a hydroxyl group, and an acryloyl group. It contains a repeating unit that is an alkyl group having 1 to 6 carbon atoms or hydrogen.

For example, in formula (I) above, m is a methylene group, n is a methyl group, p is a single bond, and q is an alkyl group having 5 or less carbon atoms including a methyl group and a glycidyl group (epoxy group). an alkyl group having 8 or less carbon atoms including a hydroxyl group and an acryloyl group.

In one embodiment of the present invention, specific examples of repeating units that can be contained in the (meth)acryloyl polymer (C) include the following formulas (II-a), (II-b), and (II-c) ) are shown.

In one embodiment of the present invention, in the (meth)acryloyl polymer (C), the repeating unit of the formula (II-a) is a repeating unit of the formula (II-a), a repeating unit of the formula (II-b) It is preferably from 30 to 85 mol %, more preferably from 40 to 80 mol %, based on the total number of moles of the units and repeating units of formula (II-c). The repeating unit of formula (II-b) is preferably 5 to 30 mol %, more preferably 10 to 25 mol %, based on the total number of moles. The repeating unit of formula (II-c) is preferably 10 to 40 mol %, more preferably 10 to 35 mol %, based on the total number of moles. In a preferred embodiment of the present invention, based on the total number of moles of repeating units of formula (II-a), repeating units of formula (II-b), and repeating units of formula (II-c), The repeating unit of the formula (II-a) is 30 to 85 mol%, the repeating unit of the formula (II-b) is 5 to 30 mol%, and the repeating unit of the formula (II-c) is 10 to 40 mol %. In a more preferred embodiment of the present invention, based on the total number of moles of repeating units of formula (II-a), repeating units of formula (II-b), and repeating units of formula (II-c) , the repeating unit of the formula (II-a) is 40 to 80 mol%, the repeating unit of the formula (II-b) is 10 to 25 mol%, and the repeating unit of the formula (II-c) The unit is 10 to 35 mol %.

In one embodiment of the present invention, the molar ratio of the repeating unit of formula (II-a), the repeating unit of formula (II-b), and the repeating unit of formula (II-c) is Preferably, it is 4.5-5.5:1.5-2.5:2.5-3.5, for example 5:2:3.

In one embodiment of the present invention, the (meth)acryloyl polymer (C) may be added with a polyfunctional acrylate compound having multiple acrylate groups. Multifunctional acrylate compounds having multiple acrylate groups that may be added to the (meth)acryloyl polymer (C) may preferably contain 3 or more acrylate groups. In a preferred embodiment of the present invention, the polyfunctional acrylate compound having multiple acrylate groups that may be added to the (meth)acryloyl polymer (C) may be a pentaerythritol-based polyfunctional acrylate compound. In a preferred embodiment of the present invention, the (meth)acryloyl polymer (C) further contains a pentaerythritol-based polyfunctional acrylate compound. As polyfunctional acrylate compounds having a plurality of acrylate groups, for example, pentaerythritol tetraacrylate represented by the following formula (III-a), and dipentaerythritol hexaacrylate represented by the formula (III-b), and Pentaerythritol triacrylate and the like are used. In a preferred embodiment of the present invention, the pentaerythritol-based polyfunctional acrylate compound includes pentaerythritol tetraacrylate represented by the following formula (III-a) and dipentaerythritol hexa represented by the formula (III-b). It is one or more selected from the group consisting of acrylate and pentaerythritol triacrylate.

In one embodiment of the present invention, the polyfunctional acrylate compound having multiple acrylate groups that may be added to the (meth)acryloyl polymer (C) is preferably 70% by mass or less, more preferably 50% by mass or less. In a preferred embodiment of the present invention, the pentaerythritol-based polyfunctional acrylate compound is included in an amount of 70% by weight or less based on the total weight of the resin composition. In a more preferred embodiment of the present invention, the pentaerythritol-based multifunctional acrylate compound is included in an amount of 50% by weight or less based on the total weight of the resin composition. Thus, by adding a polyfunctional acrylate compound to the above resin composition and reacting it with the acryloyl group, glycidyl group (epoxy group), and hydroxyl group contained in the side chain of the (meth)acryloyl polymer, higher resistance can be achieved. A scratchable surface film can be formed.

<Organic solvent>
The resin composition used for the surface layer contains an organic solvent as a diluent. In an embodiment of the present invention, the resin composition used for the surface layer contains an organic solvent (A) with a boiling point of less than 120°C and an organic solvent (B) with a boiling point of 120°C or higher as dilution solvents. As used herein, the boiling point means the boiling point under 1 atm.

In an embodiment of the present invention, the boiling point of the organic solvent (A) having a boiling point of less than 120°C is, for example, 40°C, 45°C, 50°C, 55°C, 60°C, 65°C, 70°C, 75°C, and 80°C. , 85°C, 90°C, 95°C, 100°C, 105°C, 110°C, 111°C, 112°C, 113°C, 114°C, 115°C, 116°C, 117°C, 118°C, 119°C, etc. good. In the embodiment of the present invention, the boiling point of the organic solvent (A) having a boiling point of less than 120°C is, for example, 40°C or more and less than 120°C, 45°C or more and less than 120°C, 50°C or more and less than 120°C, 55°C or more and 120°C. 60°C to 120°C, 65°C to 120°C, 70°C to 120°C, 75°C to 120°C, 80°C to 120°C, 85°C to 120°C, 90°C to 120°C , 95°C to 120°C, 100°C to 120°C, 105°C to 120°C, 110°C to 120°C, 111°C to 120°C, 112°C to 120°C, 113°C to 120°C, 114° C. or more and less than 120° C., 115° C. or more and less than 120° C., 116° C. or more and less than 120° C., 117° C. or more and less than 120° C., 118° C. or more and less than 120° C., 119° C. or more and less than 120° C., and the like. In the embodiment of the present invention, the boiling point of the organic solvent (A) having a boiling point of less than 120°C is preferably 40°C or more and less than 120°C, more preferably 65°C or more and less than 120°C. , and more preferably 90°C or higher and lower than 120°C.

Examples of the organic solvent (A) having a boiling point of less than 120° C. that can be used in the present invention include methyl isobutyl ketone (MIBK; boiling point: 116° C.), acetone (boiling point: 56° C.), isopropyl alcohol (boiling point: 83° C.), methyl ethyl ketone (boiling point: 80° C.), 2-butanol (boiling point: 100° C.), toluene (boiling point: 111° C.), etc., but not limited thereto. The organic solvent (A) that can be used in the present invention may preferably be methyl isobutyl ketone (MIBK), isopropyl alcohol, methyl ethyl ketone, 2-butanol, toluene, more preferably methyl isobutyl ketone (MIBK), 2 -butanol, toluene, and more preferably methyl isobutyl ketone (MIBK). In one preferred embodiment of the invention, organic solvent (A) is methyl isobutyl ketone (MIBK).

In the embodiment of the present invention, the boiling point of the organic solvent (B) having a boiling point of 120° C. or higher is, for example, 120° C., 125° C., 130° C., 135° C., 140° C., 145° C., 150° C., 155° C., 160° C. , 165°C, 170°C, 175°C, 180°C, 185°C, 190°C, 195°C, 200°C, 205°C, 210°C, 215°C, 220°C, 225°C, 230°C, 235°C, 240°C, 245°C °C, 250 °C, and the like. In the embodiment of the present invention, the boiling point of the organic solvent (B) having a boiling point of 120° C. or higher is, for example, 120° C. or higher and 250° C. or lower, 120° C. or higher and 245° C. or lower, 120° C. or higher and 240° C. or lower, 120° C. or higher and 235° C. 120°C to 230°C, 120°C to 225°C, 120°C to 220°C, 120°C to 215°C, 120°C to 210°C, 120°C to 205°C, 120°C to 200°C , 120°C to 195°C, 120°C to 190°C, 120°C to 185°C, 120°C to 180°C, 120°C to 175°C, 120°C to 170°C, 120°C to 165°C, 120°C to 160°C, 120°C to 155°C, 120°C to 150°C, 120°C to 145°C, 120°C to 140°C, 120°C to 135°C, 120°C to 130°C, 120 ℃ or more and 125 ℃ or less, and the like. In the embodiment of the present invention, the boiling point of the organic solvent (B) having a boiling point of 120° C. or higher is preferably 120° C. or higher and 250° C. or lower, more preferably 120° C. or higher and 205° C. or lower. , and more preferably 120° C. or higher and 160° C. or lower.

Examples of the organic solvent (B) having a boiling point of 120°C or higher that can be used in the present invention include cyclohexanone (boiling point: 155.6°C), methylcyclohexanol (174°C), methylcyclohexanone (163°C), Examples include, but are not limited to, phenylmethanol (205°C), diethylene glycol monobutyl ether (230°C), and the like. The organic solvent (B) that can be used in the present invention is preferably cyclohexanone, methylcyclohexanol, methylcyclohexanone, phenylmethanol, more preferably cyclohexanone, methylcyclohexanol, methylcyclohexanone, and further More preferably, it may be cyclohexanone. In a preferred embodiment of the invention, organic solvent (B) is cyclohexanone.

In the embodiment of the present invention, the resin composition used for the surface layer comprises an organic solvent (A) having a boiling point of less than 120°C and an organic solvent (B) having a boiling point of 120°C or higher. It is contained in the range of 7:3. The resin composition of the present invention contains an organic solvent (A) having a boiling point of less than 120°C and an organic solvent (B) having a boiling point of 120°C or higher at a mass ratio of, for example, 3:7, 3.5. :7 (ie 1:2), 4:6, 5:5, 6:4, 7:3.5 (ie 2:1), 7:3.

The resin composition of the present invention contains an organic solvent (A) having a boiling point of less than 120°C and an organic solvent (B) having a boiling point of 120°C or higher at a mass ratio of, for example,
3:7-7:3, 3:7-7:3.5 (ie 2:1), 3:7-6:4, 3:7-5:5, 3:7-4:6, 3: 7-3.5:7 (ie 1:2);
3.5:7 (ie 1:2) to 7:3, 3.5:7 (ie 1:2) to 7:3.5 (ie 2:1), 3.5:7 (ie 1:2 ) to 6:4, 3.5:7 (ie 1:2) to 5:5, 3.5:7 (ie 1:2) to 4:6;
4:6-7:3, 4:6-7:3.5 (ie 2:1), 4:6-6:4, 4:6-5:5;
5:5 to 7:3, 5:5 to 7:3.5 (ie 2:1), 5:5 to 6:4;
6:4 to 7:3, 6:4 to 7:3.5 (ie 2:1);
7:3.5 (ie 2:1) to 7:3;
may be contained in

In a preferred embodiment of the present invention, the resin composition contains an organic solvent (A) having a boiling point of less than 120°C and an organic solvent (B) having a boiling point of 120°C or higher, in a mass ratio of
3:7-7:3, 3:7-7:3.5 (ie 2:1), 3:7-6:4, 3:7-5:5;
3.5:7 (ie 1:2) to 7:3, 3.5:7 (ie 1:2) to 7:3.5 (ie 2:1), 3.5:7 (ie 1:2 ) to 6:4, 3.5:7 (ie 1:2) to 5:5;
4:6-7:3, 4:6-7:3.5 (ie 2:1), 4:6-6:4, 4:6-5:5;
may be contained in

In a preferred embodiment of the present invention, the resin composition used for the surface layer contains 30 to 50% by mass of an organic solvent (A) having a boiling point of less than 120° C., based on the total mass of the diluent solvent in the resin composition. and 70 to 50% by mass of an organic solvent (B) having a boiling point of 120° C. or higher.

In the present invention, the resin composition used for the surface layer contains the organic solvent (A) and the organic solvent (B) in a ratio within the above range, so that the coating property, moldability, and It has excellent tack-free property, and in the laminate after coating and drying the resin composition, in addition to high hardness and excellent scratch resistance, the coating adhesion of the laminate after environmental tests is effective. can be substantially improved.

<Other components in the resin composition>
The resin composition used for the surface layer preferably further contains a leveling agent in addition to the (meth)acryloyl polymer (C) described above. As the leveling agent, for example, a fluorine-based additive, a silicone-based additive, or the like is used.

Fluorinated additives include Megafac RS-56, RS-75, RS-76-E, RS-76-NS, RS-78, RS-90 manufactured by DIC, Futergent 710FL, 220P, 208G, and 601AD manufactured by Neos. , 602A, 650A, 228P, and phtergent 240GFTX-218 (all of which are fluorine-containing UV-reactive group-containing oligomers).

In addition, as the silicone additive, BYK-UV3500 and BYK-UV3505 manufactured by BYK Chemie (both of which are acrylic group-containing polyether-modified polydimethylsiloxane) and the like are used, and among these, BYK-UV3500 and the like are silicone additives. is preferred as

The resin composition used for the surface layer preferably contains a leveling agent of 0.1% by mass or more and 10% by mass or less based on the total mass of the resin composition, and the content of the leveling agent in the resin composition is It is more preferably 0.5% by mass or more and 7% by mass or less, and still more preferably 1% by mass or more and 5% by mass or less.

In one embodiment of the present invention, the resin composition used for the surface layer may be a curable resin composition. In a preferred embodiment of the invention, the above resin composition is radiation curable. In one embodiment of the present invention, the radiation-curable resin composition may be energy-ray-curable or heat-curable, preferably energy-ray-curable, more preferably UV-curable. Therefore, the resin composition used for the surface layer preferably further contains a photopolymerization initiator. In a preferred embodiment of the present invention, the resin composition further contains a photopolymerization initiator.

Photoinitiators include IRGACURE 184 (1-hydroxy-cyclohexyl-phenyl-ketone), IRGACURE 1173 (2-hydroxy-2-methyl-1-phenyl-propan-1-one), IRGACURE TPO (2,4,6 -trimethylbenzoyl-diphenyl-phosphine oxide), IRGACURE 819 (bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide), EsacureONE (oligo(2-hydroxy-2-methyl-1-[4-( 1-methylvinyl)phenyl]propanone) and the like are used, and among these, IRGACURE TPO and the like are preferable as the photopolymerization initiator from the viewpoint of heat resistance.

The resin composition used for the surface layer contains, for example, 1% by mass or more and 6% by mass or less of a photopolymerization initiator based on the total mass of the resin composition. The content of the photopolymerization initiator in the resin composition is more preferably 2% by mass or more and 5% by mass or less, and still more preferably 3% by mass or more and 4% by mass or less.

The resin composition used for the surface layer is selected from the group consisting of other additives such as heat stabilizers, antioxidants, flame retardants, flame retardant aids, ultraviolet absorbers, release agents, and colorants. It may also contain at least one additive. In addition, antistatic agents, fluorescent whitening agents, antifogging agents, fluidity improvers, plasticizers, dispersants, antibacterial agents, inorganic oxide nanoparticles, etc. may be added to the resin composition as long as they do not significantly impair the desired physical properties. may be added.

In the resin composition used for the surface layer, the (meth)acryloyl polymer (C), the organic solvent (A), and the organic solvent (B) preferably contain 60% by mass or more, more preferably 80% by mass. % or more, particularly preferably 90 mass % or more.

Therefore, the content of components other than the main three-component (meth)acryloyl polymer (C)), the organic solvent (A), and the organic solvent (B) in the resin composition is less than 40% by mass. Preferably, it is less than 20% by mass, and particularly preferably less than 10% by mass.

<Production of resin composition>
The resin composition used for the surface layer is produced by blending materials such as the above-described (meth)acryloyl polymer (C), organic solvent (A), organic solvent (B), and the like. For example, a resin composition is produced by mixing each component such as a (meth)acryloyl polymer using a tumbler.

<Properties of resin composition>
(i) Tack-free property in uncured state The resin composition used for the surface layer in the present invention is excellent in tack-free property. For this reason, even if the uncured resin composition comes into contact with other substances such as the hands of workers, it is possible to maintain a predetermined shape, and the resin composition adheres to the surface of the contacting substance. Partial adhesion is suppressed. Thus, according to the resin composition having excellent tack-free property, it is possible to easily carry out curing processing after molding into a shape suitable for various uses. In addition, it is easy to store or distribute the resin composition in a predetermined shape before curing.

(ii) Moldability in an uncured state (pressure moldability)
The resin composition used for the surface layer of the present invention also has excellent moldability in an uncured state. The moldability of the above resin composition is evaluated, for example, as follows. That is, after coating the above resin composition on the surface of the base material layer and drying it, the obtained coated product is placed on a mold having convex portions and heated to obtain air pressure moldability. can be evaluated based on whether or not the sheet-shaped resin composition is appropriately stretched following the protrusions and whether or not cracks occur when the above is carried out.

Although the details are omitted, it was confirmed in such an evaluation test that the resin composition used for the surface layer can be stretched while following the protrusions without causing cracks during pressure moldability.

1.3 Laminate Manufacturing Method A laminate including a substrate layer is manufactured as follows.

<Production of substrate layer>
First, a material such as a resin composition constituting the substrate layer is processed into a layer (sheet) by a conventional method to produce the substrate layer. For example, it is a method by extrusion molding and cast molding. As an example of extrusion molding, pellets, flakes or powder of the resin composition used for the base material layer are melted and kneaded with an extruder, extruded from a T-die or the like, and the resulting semi-molten sheet is pressed between rolls. A method of cooling and solidifying to form a sheet can be mentioned. The composition of the base material layer is as described above. The substrate layer may be composed of a single layer or may be composed of multiple layers. In one embodiment of the present invention, the substrate layer 30 may be composed of, for example, a first resin layer 31 and a second resin layer 32 (FIG. 1).

<Formation of surface layer>
Then, the resin composition used for the surface layer produced as described above is applied to the outer surface of the substrate layer having a single layer or a plurality of layers to form a surface layer. The composition and properties of the resin composition used for the surface layer are as described above.

In an embodiment of the invention, the surface layer comprises
Step 1 of applying a resin composition containing a radiation-curable resin and an organic solvent to the surface of a substrate layer to obtain a coated product;
It is formed by a method including step 2 of drying the obtained coated material to form a surface layer on the surface of the substrate layer. Then, according to the method of the present invention, it is possible to obtain a laminate in which the coating film adhesion of the surface layer in the laminate has an evaluation result of 0 as determined by the evaluation method of JIS K 5600-5-6. .

In the present invention, gravure coating, die coating, curtain coating, rod coating, bar coating, blade coating, knife coating, dip coating, etc. can be used as a method for applying the resin composition used for the surface layer to the substrate layer. can be done. A suitable one may be selected from these according to the viscosity of the paint and the thickness of the coating layer. For example, when obtaining a surface layer having a dry film thickness of 5 μm with a paint having a viscosity of 10 mPa·s, it is desirable to use gravure coating suitable for low-viscosity thin film coating.

In the present invention, hot air drying, infrared drying, far infrared drying, drum heating drying, electromagnetic induction heating drying, and the like can be used as the method for drying the coated material. It is desirable to use hot air drying from the viewpoint of productivity and controllability.

It is desirable that the hot air drying oven used in the above process of drying the coated material has at least two or more zones so that the temperature and air velocity can be independently controlled. Hot air supply methods include follow-flow and counter-flow, which supply hot air parallel to the direction in which the substrate is conveyed, slit nozzle methods that supply hot air perpendicular to the direction in which the substrate is conveyed, and diagonal directions that are intermediate between the two. A method of supplying hot air is used. A roll support method, a floating method, or the like can be used as a method for conveying the substrate in the drying furnace. Also, between the coating step and the drying step in the drying oven, a zone in which the drying is not actively performed may be provided for the purpose of adjusting the appearance of the coated surface and adjusting the differential pressure between the inside and outside of the drying oven. A cooling zone or the like may also be provided after passing through the drying oven.

In a preferred embodiment of the present invention, a method of manufacturing a laminate as described above, said method comprising:
Step 1 of applying a resin composition containing a radiation-curable resin and an organic solvent to the surface of a substrate layer to obtain a coated product;
Step 2 of drying the obtained coated material to form a surface layer on the surface of the substrate layer
including
The laminate comprises at least a substrate layer and a surface layer,
The resin composition contains an organic solvent (A) with a boiling point of less than 120° C. and an organic solvent (B) with a boiling point of 120° C. or higher in a mass ratio of A:B=3:7 to 7:3. death,
The resin composition contains a (meth)acryloyl polymer (C), and the (meth)acryloyl polymer (C) has a (meth)acrylic equivalent weight of 200 to 600 g/eq and a weight average of 5,000 to 200,000. has a molecular weight,
A method is provided in which the coating film adhesion of the surface layer is 0 as an evaluation result determined by the evaluation method of JIS K 5600-5-6.

In one embodiment of the present invention, at least two drying ovens may be used in step 2 above. In a preferred embodiment of the present invention, at least two drying ovens are used in step 2, and the drying oven temperature in the last drying oven is higher than the drying oven temperature in the first drying oven.

In a preferred embodiment of the present invention, at least two drying ovens capable of heating the coated material to 60° C. or higher may be used in step 2 above. In this embodiment, the drying oven temperature in the first drying oven may be in the range of 90-120°C, and the drying oven temperature in the second drying oven may be in the range of 100-140°C. In a more preferred embodiment of the present invention, in step 2, at least two drying ovens capable of heating the coated material to 60°C or higher are used, and the drying oven temperature in the first drying oven is 90 to 120°C. range, and the drying oven temperature in the second drying oven is in the range of 100 to 140°C.

In a preferred embodiment of the present invention, in step 2, at least two drying ovens capable of heating the coated material to 60° C. or higher are used, and the drying oven temperature in the last drying oven is equal to that of the drying oven in the first drying oven. higher than temperature. In a more preferred embodiment of the present invention, in step 2, at least two drying ovens capable of heating the coated material to 60°C or higher are used, and the drying oven temperature in the first drying oven is in the range of 90 to 120°C. and the drying oven temperature in the final drying oven is in the range of 100 to 140°C.

In a preferred embodiment of the present invention, the base layer has a thickness of 0.1 mm to 1.0 mm, and the resin composition layer applied to the surface of the base layer has a thickness of 1.0 μm. ~10 μm.

A masking film may be laminated on the surface of the laminate comprising the substrate layer and the surface layer thus obtained on the surface layer side.

<Physical properties of surface layer>
(i) Thickness In the present invention, the thickness of the surface layer 20 is preferably 1.0 μm to 10 μm. The thickness of the surface layer is, for example, 2.0 μm to 8.0 μm, or 3.0 μm to 7.0 μm.

(ii) Scratch resistance Curing the surface layer achieves high scratch resistance. As will be described later in detail, when a laminate having a surface layer is cured, the scratch resistance on the surface of the surface layer is superior to cured PMMA resin (polymethyl methacrylate resin) and lens resin. confirmed.

(iii) Hardness The hardened surface layer has high hardness. Specifically, a pencil hardness of B or higher in the evaluation method of JIS K 5600-5-4:1999 can be achieved. The surface of the cured surface layer preferably has a pencil hardness of F or higher, particularly preferably 2H or higher.

(vi) Coating film adhesion The surface layer obtained by curing the resin composition also has excellent coating film adhesion to the substrate layer. Specifically, after coating the resin composition on the substrate layer, UV curing and an environmental test were performed as pretreatments under the following conditions, and the coating film adhesion after the environmental test was evaluated.
<Pretreatment: UV curing>
UV irradiation device: COST-40 manufactured by GS Yuasa Co., Ltd.
UV lamp (HAN250AL)
Integrated light quantity: 750 mJ/cm ² (Ultraviolet integrated illuminance meter: UVPF-A2 manufactured by Iwasaki Electric Co., Ltd. / PD-365A2 photodetector)
Peak intensity 250 mW/cm ² (ultraviolet illuminance meter: UVPF-A2 manufactured by Iwasaki Electric Co., Ltd./photodetector PD-365A2)
<Environmental test>
1,000 hour endurance test at 85°C/85% RH <Paint film adhesion test>
JIS K 5600-5-6: Conducting a coating film adhesion test according to 1999 For the laminate of the present invention, the evaluation result determined by the evaluation method of JIS K 5600-5-6: 1999 is 0, and the evaluation result Better results than 1-5 were obtained.

As is clear from the properties of the surface layer obtained after curing, the surface of the cured film on the surface layer side has excellent properties. That is, the surface of the cured film on the surface layer side has a high pencil hardness, preferably a pencil hardness of B or higher according to JISK 5600-5-4: 1999, high scratch resistance, and excellent adhesion, for example, JISK Adhesion with an evaluation result of 0 level in 5600-5-6 is achieved.

<Physical properties of laminate>
(i) Residual Solvent Amount In one embodiment of the present invention, a laminate having a residual solvent amount of 82 mg/m ² or less may be provided. In an embodiment of the present invention, the residual solvent amount in the laminate is 82 mg/m ² or less, 80 mg/m 2 or less, 75 mg/m ² or less, 70 mg/m ^{2 or} less, 65 mg/m ² or less, 60 mg/m ² or less. , 55 mg/m ² or less, 50 mg/m ² or less, 45 mg/m ² or less, 40 mg/m 2 or less, 35 mg/m ^{2 or} less, 30 mg/m ² or less, 25 mg/m ² or less, and the like. In the present invention, the smaller the amount of residual solvent in the laminate, the better.

According to the method of the present invention, a laminate comprising at least a substrate layer and a surface layer provided on the surface of the substrate layer,
The surface layer contained an organic solvent (A) with a boiling point of less than 120°C and an organic solvent (B) with a boiling point of 120°C or higher in a mass ratio of A:B = 3:7 to 7:3. Formed by coating the resin composition, drying at least in a first drying oven at a temperature in the range of 90 to 120 ° C., and then drying in a second drying oven at a temperature in the range of 100 to 140 ° C. has been
The resin composition contains a (meth)acryloyl polymer (C), and the (meth)acryloyl polymer (C) has a (meth)acrylic equivalent weight of 200 to 600 g/eq and a weight average of 5,000 to 200,000. has a molecular weight,
As for the coating film adhesion of the surface layer, it is possible to obtain a laminate in which the evaluation result determined by the evaluation method of JIS K 5600-5-6 is 0.

(ii) appearance (pinhole)
The presence or absence of pinholes is visually evaluated by transmitted light and reflected light, and less than 10 pinholes/ ^m2 with a size of 0.06 mmφ or more and 0.3 mm2 ^or more are accepted, and 10/m2 ^or more. I failed.

<Curing film>
The laminate can be obtained as a cured film by drying and curing the coated product. When a masking film is attached, the masking film is removed and then cured. In a preferred embodiment of the invention the laminate is a cured film.

<Molded body>
A molded article can be obtained by thermoforming the laminate described above. In one embodiment of the present invention, there is provided a molded body obtained by thermoforming the laminate described above.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to Examples. However, the present invention is not limited to the following examples, and can be arbitrarily modified without departing from the gist of the present invention.

<Example 1>
By mixing cyclohexanone and methyl isobutyl ketone (MIBK) with an ultraviolet curable acryloyl polymer (ARTCURE RA-3602MI manufactured by Negami Kogyo Co., Ltd.), the mass ratio of MIBK:cyclohexanone is 6:4, and the solid content concentration is 20 mass. adjusted to be %. Furthermore, a photopolymerization initiator IRGACURE 184 (3% by mass based on the solid content) was added to obtain a resin composition used for the surface layer.

The resin composition used for the surface layer obtained as described above was applied to the PMMA side of a polycarbonate (PC)/polymethyl methacrylate (PMMA) film as a substrate layer to obtain a coated product. .

The coating step was performed using a 120-line gravure roll. After that, in the drying step, the coated material is dried at 90 ° C. in the first drying oven (“pre-drying oven” in the table below) and at 120 ° C. in the last drying oven (“post-drying oven” in the table below). As a result, a laminate was obtained in which a radiation-curable resin layer having a thickness of about 4 micrometers was formed as a surface layer on the surface on the PMMA side. The resulting laminate was evaluated for coating film adhesion, residual solvent amount, and presence or absence of pinholes. The evaluation results are shown in the table below.

<Examples 2 to 7, Comparative Examples 1 to 14>
A laminate was obtained in the same manner as in Example 1, except that the composition and drying temperature were changed to those shown in the table below. The resulting laminate was evaluated in the same manner as in Example 1 for coating film adhesion, residual solvent amount, and presence or absence of pinholes. The evaluation results are shown in the table below.

As described above, the laminate of the present invention does not impair the properties required for a laminate for a molded body, such as moldability, scratch resistance, hardness, adhesion, and good appearance, even after environmental tests. It has an excellent feature that the coating film adhesion can be effectively improved. Therefore, the laminate of the present invention is suitable for applications such as automobile interiors and housings for electronic devices.

REFERENCE SIGNS LIST 10 laminate 20 surface layer 30 base layer 31 first resin layer 32 second resin layer

Claims (21)

A laminate comprising at least a substrate layer and a surface layer provided on the surface of the substrate layer,
The surface layer contained an organic solvent (A) with a boiling point of less than 120°C and an organic solvent (B) with a boiling point of 120°C or higher in a mass ratio of A:B = 3:7 to 7:3. After applying the resin composition and drying at least in the first drying oven at a temperature in the range of 90 to 120 ° C., drying in the second drying oven at a temperature in the range of 100 to 140 ° C., UV It is formed by curing,
The organic solvent (A) is selected from the group consisting of methyl isobutyl ketone, acetone , and methyl ethyl ketone ,
The organic solvent (B) is selected from the group consisting of cyclohexanone and methylcyclohexanone ,
The resin composition contains a (meth)acryloyl polymer (C), and the (meth)acryloyl polymer (C) has a (meth)acrylic equivalent weight of 200 to 600 g/eq and a weight average of 5,000 to 200,000. has a molecular weight,
A laminate in which the coating film adhesion of the surface layer after UV curing is 0 as an evaluation result determined by the evaluation method of JIS K 5600-5-6. The laminate according to claim 1, wherein the (meth)acryloyl polymer (C) contains a repeating unit represented by the following formula (I).

(In formula (I),
m is an alkylene group having 1 to 4 carbon atoms or a single bond,
n is an alkyl group having 1 to 4 carbon atoms or hydrogen,
p is a single bond or an alkylene group having 1 or 2 carbon atoms,
q is an alkyl group having 1 to 12 carbon atoms in total, which may contain at least one substituent of an epoxy group, a hydroxyl group, an acryloyl group, and a methacryloyl group, or hydrogen. ) In the formula (I),
m is an alkylene group having 1 or 2 carbon atoms,
n is an alkyl group having 1 or 2 carbon atoms,
p is a single bond or a methylene group,
3. The laminate according to claim 2, wherein q is an alkyl group having a total of 1 to 6 carbon atoms which may contain at least one substituent of a glycidyl group, a hydroxyl group, and an acryloyl group, or hydrogen. In the formula (I), m is a methylene group, n is a methyl group, p is a single bond, q is a methyl group, an alkyl group having 5 or less carbon atoms including a glycidyl group (epoxy group), Alternatively, the laminate according to claim 3, which is an alkyl group having 8 or less carbon atoms containing a hydroxyl group and an acryloyl group. (Meth)acryloyl polymer (C) contains at least one of repeating units represented by the following formula (II-a), formula (II-b), and formula (II-c), according to claim 2 Laminate as described.

Based on the total number of moles of the repeating unit of the formula (II-a), the repeating unit of the formula (II-b), and the repeating unit of the formula (II-c), the formula (II-a) The repeating unit is 30 to 85 mol%, the repeating unit of formula (II-b) is 5 to 30 mol%, and the repeating unit of formula (II-c) is 10 to 40 mol%. A laminate according to claim 5, wherein: The molar ratio of the repeating unit of formula (II-a), the repeating unit of formula (II-b), and the repeating unit of formula (II-c) is 4.5 to 5.5:1. 5 to 2.5: The laminate according to claim 5, wherein the ratio is 2.5 to 3.5. The (meth)acryloyl polymer (C) further contains a pentaerythritol-based polyfunctional acrylate compound. A laminate according to any one of claims 1 to 7. The pentaerythritol-based polyfunctional acrylate compound is pentaerythritol tetraacrylate represented by the following formula (III-a), and dipentaerythritol hexaacrylate represented by formula (III-b), and pentaerythritol triacrylate. The laminate according to claim 8, which is one or more selected from the group consisting of.

The laminate according to claim 8 or 9, wherein the pentaerythritol-based polyfunctional acrylate compound is contained in an amount of 70% by mass or less based on the total mass of the resin composition. The laminate according to any one of claims 1 to 10, wherein the resin composition is radiation curable. The laminate according to any one of claims 1 to 11, wherein the resin composition further contains a photopolymerization initiator. The laminate according to any one of claims 1 to 12, wherein the base layer contains a thermoplastic resin. The base material layer is polymethyl methacrylate,
The organic solvent A is methyl isobutyl ketone,
The organic solvent B is cyclohexanone,
A laminate according to any one of claims 1 to 13. The laminate according to any one of claims 1 to 14 , which is a decorative sheet. A molded product obtained by thermoforming the laminate according to any one of claims 1 to 15 . A method for producing a laminate according to any one of claims 1 to 15, the method comprising
Step 1 of applying a resin composition containing a radiation-curable resin and an organic solvent to the surface of a substrate layer to obtain a coated product;
The obtained coated material is dried in a first drying oven at a temperature in the range of 90 to 120 ° C., and then dried in a second drying oven at a temperature in the range of 100 to 140 ° C. to obtain the substrate. Step 2 of forming a surface layer on the surface of the material layer;
UV curing,
The laminate comprises at least a substrate layer and a surface layer,
The resin composition contains an organic solvent (A) with a boiling point of less than 120° C. and an organic solvent (B) with a boiling point of 120° C. or higher in a mass ratio of A:B=3:7 to 7:3. death,
The organic solvent (A) is selected from the group consisting of methyl isobutyl ketone, acetone , and methyl ethyl ketone ,
The organic solvent (B) is selected from the group consisting of cyclohexanone and methylcyclohexanone ,
The resin composition contains a (meth)acryloyl polymer (C), and the (meth)acryloyl polymer (C) has a (meth)acrylic equivalent weight of 200 to 600 g/eq and a weight average of 5,000 to 200,000. has a molecular weight,
A method in which the coating film adhesion of the surface layer after UV curing is 0 as determined by the evaluation method of JIS K 5600-5-6. 18. The method of claim 17 , wherein in step 2, at least two drying ovens are used and the drying oven temperature in the last drying oven is higher than the drying oven temperature in the first drying oven. In step 2, at least two drying ovens capable of heating the coated material to 60 ° C. or higher are used,
The method according to claim 17 or 18 , wherein the drying oven temperature in the first drying oven is in the range of 90-120°C and the drying oven temperature in the second drying oven is in the range of 100-140°C. 17. The thickness of the substrate layer is 0.1 mm to 1.0 mm, and the thickness of the layer of the resin composition applied to the surface of the substrate layer is 1.0 μm to 10 μm. 20. The method according to any one of 19 . The base material layer is polymethyl methacrylate,
The organic solvent A is methyl isobutyl ketone,
The organic solvent B is cyclohexanone,
The method according to any one of claims 17-20.

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