JP2014196430A - Active energy ray-curable resin composition, cured film obtained from the composition, and laminate having the cured film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an active energy ray-curable resin composition from which a cured film can be formed, which film has all of flexibility capable of following-up deformation at a three-dimensional processing time, breaking elongation, excellent mechanical strength, scratch repairability, scratch resistance, weather resistance, heat resistance, stain resistance and blocking resistance simultaneously.SOLUTION: An active energy ray-curable resin composition contains a urethane (meth)acrylate-based oligomer (A) being a reaction product when polyisocyanate (a-1), polycarbonate polyol (a-2) and hydroxyalkyl (meth)acrylate (a-3) are reacted with one another. A diol constituent unit of the polycarbonate polyol (a-2) contains 1,4-butanediol or both of 1,4-butanediol and 1,6-hexanediol. The cured film, which is obtained by irradiating the active energy ray-curable resin composition with active energy, has 100-1,000 MPa tensile elasticity at 23°C.

Description

  The present invention relates to an active energy ray-curable resin composition containing a urethane (meth) acrylate-based oligomer, a cured film obtained by irradiating the composition with active energy rays, and a laminate and a decorative film using the cured film.

Conventionally, radical polymerization type active energy ray-curable resin compositions are cured in a short time by irradiation with active energy rays, and are excellent in scratch resistance, chemical resistance, contamination resistance, weather resistance, heat resistance, etc. In addition, since a molded product can be provided, it is widely used in various surface processing fields and cast molded product applications.
Above all, from the viewpoint of curability and work efficiency, the active energy ray-curable resin composition is previously cured to create a resin sheet, and after surface treatment, etc., three-dimensional processing is performed at room temperature or under heating conditions. Although the method is used, in this case, the active energy ray-curable resin sheet needs flexibility and elongation to follow deformation during three-dimensional processing.

As such a resin sheet, Patent Document 1 discloses an active energy ray-curable resin laminate that exhibits a specific elongation at break and has a cured layer of a composition containing a urethane (meth) acrylate oligomer. .
On the other hand, Patent Document 2 discloses a decorative sheet for building materials that is a cured product of a resin composition made of urethane acrylate, and is said to be excellent in contamination resistance, which is a characteristic required for a surface-protective resin sheet. ing.

  In addition, as a concept that gives excellent scratch resistance, a self-repairing property in which a scratch once attached is recovered over time has been proposed. In Patent Documents 3, 4, and 5, active energy containing urethane acrylate containing a polycaprolactone polymer (Patent Document 3), a polyether polymer (Patent Document 4), and a diene polymer (Patent Document 5), respectively. The line curable resin composition exhibits self-healing properties and is excellent in scratch resistance.

Patent Document 6 also discloses an antireflective substrate including a transparent cured product layer obtained by curing a photocurable resin containing a urethane acrylate containing a polycarbonate polymer as a constituent component. It is said to exhibit excellent self-healing and scratch resistance.
Patent Document 7 discloses a light transmission layer of an optical information recording medium obtained by curing a mixture of urethane (meth) acrylate, isobornyl (meth) acrylate, and other hydrophobic (meth) acrylate with a photopolymerization initiator. It has been shown that this light transmission layer has high hardness and is excellent in adhesion to polycarbonate and low moisture absorption characteristics.

  In Patent Document 8, a cured film obtained by curing a photocurable resin containing a urethane acrylate having a low molecular weight polyol having an alicyclic structure and having a number average molecular weight of 500 or less is excellent in three-dimensional processing. It has been shown to have resistance to contamination.

JP 2007-30479 A JP 2001-129938 A JP 2004-244426 A JP-A-2005-162908 JP 2010-260905 A JP 2005-99474 A JP 2010-43194 A JP 2010-222568 A

  However, although the active energy ray-curable resin laminate described in Patent Document 1 has good elongation at break and strength at elongation and is excellent in three-dimensional workability, it is inferior in stain resistance as a surface protective resin sheet. It is. In addition, the laminate described in Patent Document 1 exhibits desired characteristics by having two or more resin layers having different characteristics, and a simple resin sheet cannot be produced by single-layer coating. There is a problem that the film thickness is limited.

The decorative sheet for building materials described in Patent Document 2 does not have flexibility and elongation enough to follow the deformation of three-dimensional processing, and is inferior in three-dimensional workability even under high temperature conditions.
In Patent Documents 3, 4, 5, and 6, there is a problem that the workability is limited to the presence / absence of burrs on the cut surface and cannot follow the deformation of three-dimensional processing.
Further, the light transmission layer described in Patent Document 7 also has a problem that there is no description about workability and it cannot follow the deformation of three-dimensional processing.

Furthermore, even the cured film described in Patent Document 8 has a problem that it has a large elastic modulus, does not have a detailed description of scratch resistance, and is inferior in scratch resistance to hard materials such as nails and steel wool.
The present invention aims to solve the above-described problems, and a cured film obtained by curing can follow the deformation during three-dimensional processing, flexibility at break, and excellent mechanical strength, It is an object of the present invention to provide an active energy ray-curable resin composition having both flaw repairability, scratch resistance, heat resistance, contamination resistance, and blocking resistance.

  In addition, a cured film obtained by curing such a composition and a laminate having a layer formed of the cured film on the surface, and a cured film capable of imparting design properties or surface protection to various substrates, and the cured film It aims at providing the laminated body which has a layer which consists of, and a decorating film on the surface.

As a result of intensive studies to solve the above-mentioned problems, the present inventor has found that the active energy ray-curable resin composition of the present invention can solve the above-mentioned problems, leading to the present invention.
That is, the gist of the present invention is as follows.
(1) Urethane (meth) which is a reaction product of at least (a-1) polyisocyanate, (a-2) polycarbonate polyol, and (a-3) hydroxyalkyl (meth) acrylate
An active energy ray-curable resin composition containing an acrylate oligomer (A), wherein the diol constituent unit of the (a-2) polycarbonate polyol contains 1,4-butanediol and is cured by irradiation with active energy. An active energy ray-curable resin composition, wherein the cured film has a tensile elastic modulus at 23 ° C. of 100 to 1000 MPa.
(2) The active energy ray-curable resin composition according to (1), wherein the molecular weight between calculated crosslinking points in the composition is 1000 to 15000.
(3) The active energy ray-curable resin composition according to (1) or (2), wherein the (a-1) polyisocyanate is a polyisocyanate having an alicyclic structure having 5 to 15 carbon atoms. (4) (a-2) The proportion of 1,4-butanediol and 1,6-hexanediol in the diol constituent unit, including the constituent unit of 1,6-hexanediol in the diol constituent unit of the polycarbonate polyol 1,4-butanediol / 1,6-hexanediol =
The active energy ray-curable resin composition according to any one of (1) to (3), which is 7/3 to 10/0 (mass ratio).
(5) The (a-3) hydroxyalkyl (meth) acrylate is a hydroxyalkyl (meth) acrylate having a C2-C4 alkylene group between a (meth) acryloyl group and a hydroxyl group, The active energy ray-curable resin composition according to any one of (4).
(6) The (a-3) hydroxyalkyl (meth) acrylate is 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) Acrylate, cyclohexanedimethanol mono (meth) acrylate, addition reaction product of 2-hydroxyethyl (meth) acrylate and caprolactone, addition reaction product of 4-hydroxybutyl (meth) acrylate and caprolactone, glycidyl ether and (meth) acrylic At least one compound selected from the group consisting of an addition reaction product with an acid, a mono (meth) acrylate of glycol, pentaerythritol tri (meth) acrylate, and dipentaerythritol penta (meth) acrylate That, (1) the active energy ray curable resin composition according to (5).
(7) The active energy ray-curable resin composition for a topcoat layer for a decorative film according to any one of (1) to (6).
(8) A cured film formed by irradiating the active energy ray-curable resin composition according to any one of (1) to (7) with active energy rays.
(9) A laminate having a layer made of the cured film according to (8) on a substrate.
(10) A decorative film having, as a topcoat layer, a layer made of the cured film according to (8) on a substrate.

  According to the active energy ray-curable resin composition of the present invention, flexibility capable of following deformation during three-dimensional processing, elongation at break, and excellent mechanical strength, scratch repairability, scratch resistance, weather resistance, A cured film having a high commercial value that has both heat resistance, contamination resistance, and blocking resistance can be formed with good workability.

Embodiments of the present invention will be described in detail below. However, the description of the constituent elements described below is a representative example of the embodiments of the present invention, and the present invention is not limited to these contents. .
In the present specification, (meth) acrylate is a general term for acrylate and methacrylate, and means one or both of acrylate and methacrylate. The same applies to (meth) acryloyl and (meth) acryl.

Further, in the present specification, “to” is used in the sense of including the numerical values described before and after it as a lower limit value and an upper limit value.
Moreover, the measurement method thru | or the calculation method of the molecular weight or number average molecular weight of the raw material compound of urethane (meth) acrylate oligomers, such as (a-2) polycarbonate polyol concerning this invention, are as follows.

For compounds other than polyols having a molecular weight distribution in a gel permeation chromatogram (hereinafter abbreviated as GPC), the molecular weight can be calculated from the chemical formula, and the number average molecular weight can be determined by GPC as follows.
<Calculation of number average molecular weight by GPC>
Using GPC (“HLC-8120GPC” manufactured by Tosoh Corporation), tetrahydrofuran (THF) as a solvent, polystyrene as a standard sample, TSK gel superH1000 + H2000 + H3000 as a column, liquid feeding speed 0.5 mL / min, column oven temperature 40 The number average molecular weight is measured at ° C.

Moreover, about the polyol which has molecular weight distribution by GPC, the number average molecular weight can be calculated | required as follows by OH value.
<Calculation of number average molecular weight of polyol by OH number>
Into an Erlenmeyer flask, 2 g of polyol and 0.5 mol / L phthalic anhydride pyridine solution are added, reacted at 100 ° C. for 2 hours, and then diluted with 150 mL of acetone. Then, it titrates with 0.5 mol / L sodium hydroxide aqueous solution. Further, a titration is performed in the same manner except that no polyol is added to the Erlenmeyer flask to obtain a blank. And OH value and a number average molecular weight are computed by the following formula | equation.

OH value = {(BA) × 0.5 × 56.11 × 1000} / 2 × 1000
A: Amount of aqueous sodium hydroxide solution required for titration of polyol-containing solution B: Amount of aqueous sodium hydroxide solution required for titration of blank solution not containing polyol Number average molecular weight of polyol = {(56.11 × 1000) / OH value} × number of functional groups In the above formula, the “number of functional groups” is the number of OH groups contained in one molecule of polyol.

Moreover, about the isocyanate which has molecular weight distribution by GPC, the number average molecular weight can be calculated | required as follows by NCO%.
<Calculation of the number average molecular weight of polyisocyanate by NCO%>
Into an Erlenmeyer flask, 1 g of polyisocyanate and 20 mL of a 0.5 mol / L dibutylamine toluene solution are added, diluted with 100 mL of acetone, and reacted at 25 ° C. for 30 minutes. Thereafter, the solution is titrated with a 0.5 mol / liter hydrochloric acid aqueous solution. Moreover, titration is performed similarly except polyisocyanate was not put into the Erlenmeyer flask, and a blank is obtained. And NCO% and a number average molecular weight are computed by the following formula | equation.

NCO% = {(B1-A1) × 0.5 × 42.02} / (1 × 1000) × 100
A1: Amount of hydrochloric acid aqueous solution required for titration of polyisocyanate-containing solution (mL)
B1: Amount of hydrochloric acid aqueous solution required for titration of blank solution containing no polyisocyanate (mL)
Number average molecular weight of polyisocyanate = (42.02 / NCO%) × number of NCO groups contained in one molecule of polyisocyanate The active energy ray-curable resin composition of the present invention comprises a urethane (meth) acrylate oligomer (A ).

  The urethane (meth) acrylate oligomer (A) used in the present invention is a compound having one or more radically polymerizable (meth) acryloyl groups and at least two urethane bonds in the molecule. The urethane (meth) acrylate oligomer (A) is a cured product by active energy ray irradiation, has a balanced tensile strength and excellent tensile elongation, and has excellent surface curability as a composition, and has a tackiness. It is superior to other typical active energy ray-curable oligomers such as epoxy (meth) acrylate oligomers, acrylic (meth) acrylate oligomers, and the like in that it is difficult to remain.

  The urethane (meth) acrylate oligomer (A) in the present invention (hereinafter referred to as “the urethane (meth) acrylate oligomer (A) of the present invention)” is (a-1) polyisocyanate, (a-2) polycarbonate. It is a reaction product of a raw material containing a polyol and (a-3) hydroxyalkyl (meth) acrylate. The urethane (meth) acrylate oligomer (A) contained in the active energy ray-curable resin composition of the present invention may be one type or two or more types.

[Raw compound of urethane (meth) acrylate oligomer (A)]
Below, the raw material compound of the urethane (meth) acrylate oligomer (A) of the present invention will be explained.
(A-1) Polyisocyanate (a-1) Polyisocyanate as a raw material compound for producing the urethane (meth) acrylate oligomer (A) in the present invention has two or more isocyanate groups and isocyanate in one molecule. A compound having one or both of substituents containing a group (also referred to as “isocyanate groups”). (A-1) One type of polyisocyanate may be used, or two or more types may be used. Moreover, in 1 type of polyisocyanate, isocyanate groups may be the same and may differ.

As a substituent containing an isocyanate group, a C1-C5 alkyl group, an alkenyl group, or an alkoxyl group containing one or more isocyanate groups is mentioned, for example. The number of carbon atoms of the alkyl group or the like as a substituent containing an isocyanate group is more preferably 1 to 3.
(A-1) The number average molecular weight of the polyisocyanate is preferably 100 or more from the viewpoint of the balance between strength and elastic modulus as a cured product obtained by curing the active energy ray-curable resin composition, More preferably, it is 150 or more, more preferably 1,000 or less, and even more preferably 500 or less.

The number average molecular weight of the polyisocyanate is obtained from a calculated value from a chemical formula in the case of a polyisocyanate composed of a single monomer, or a calculated value from NCO% in the case of a polyisocyanate composed of two or more monomers. be able to.
Examples of the polyisocyanate include aliphatic polyisocyanates, polyisocyanates having an alicyclic structure, and aromatic polyisocyanates.

An aliphatic polyisocyanate is a compound having an aliphatic structure and two or more isocyanate groups bonded thereto. An aliphatic polyisocyanate is preferable from the viewpoint of enhancing the weather resistance of a cured product obtained by curing the active energy ray-curable resin composition and imparting flexibility. The aliphatic structure in the aliphatic polyisocyanate is not particularly limited, but is preferably a linear or branched alkylene group having 1 to 6 carbon atoms. Examples of such aliphatic polyisocyanates include aliphatic diisocyanates such as tetramethylene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, and dimer acid diisocyanate, and aliphatic triisocyanates such as tris (isocyanatohexyl) isocyanurate. Examples of the polyisocyanate include a polyisocyanate having an alicyclic structure from the viewpoint of mechanical strength and contamination resistance of a cured product obtained by curing the active energy ray-curable resin composition of the present invention. .

The polyisocyanate having an alicyclic structure is a compound having an alicyclic structure and two or more isocyanate groups bonded thereto. The alicyclic structure in the polyisocyanate having an alicyclic structure is not particularly limited, but preferably has 5 to 15 carbon atoms, more preferably 6 or more carbon atoms, and 7 or more carbon atoms. Particularly preferred. Moreover, it is more preferable that it is C14 or less, and it is especially preferable that it is C13 or less. Furthermore, the alicyclic structure is preferably a cycloalkylene group. Examples of the polyisocyanate having an alicyclic structure include diisocyanates having an alicyclic structure such as bis (isocyanate methyl) cyclohexane, cyclohexane diisocyanate, bis (isocyanatocyclohexyl) methane, and isophorone diisocyanate, and tris (isocyanate isophorone) isocyanate. Examples thereof include triisocyanates having an alicyclic structure such as nurate.

The polyisocyanate having an alicyclic structure is also preferable from the viewpoint of enhancing the weather resistance of a cured product obtained by curing the active energy ray-curable resin composition. As the polyisocyanate having such an alicyclic structure, For example, bis (isocyanatemethyl) cyclohexane, cyclohexane diisocyanate, bis (isocyanatocyclohexyl) methane, and isophorone diisocyanate are aromatic polyisocyanates, which are compounds having an aromatic structure and two or more isocyanate groups bonded thereto. is there. Although the aromatic structure in aromatic polyisocyanate is not specifically limited, It is preferable that it is a C6-C13 bivalent aromatic group. Examples of such aromatic polyisocyanates include aromatic diisocyanates such as tolylene diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate, m-phenylene diisocyanate, and naphthalene diisocyanate.
The aromatic polyisocyanate is preferable from the viewpoint of increasing the mechanical strength of a cured product obtained by curing the active energy ray-curable resin composition. Examples of such aromatic polyisocyanate include tolylene diisocyanate and diphenylmethane diisocyanate. Can be mentioned.

(A-2) Polycarbonate polyol The (a-2) polycarbonate polyol according to the present invention is characterized in that the diol constituent unit contains 1,4-butanediol, and 1,4-butanediol is used alone. Or containing 1,4-butanediol and 1,6-hexanediol is preferable because the effects of the present invention are good.

  That is, the (a-2) polycarbonate polyol used in the present invention is a polycarbonate diol containing 1,4-butanediol, preferably 1,4-butanediol, or 1,4-butanediol and 1,6-butanediol. Polycarbonate diol obtained by reacting diols containing hexanediol. 1,4-butanediol and 1,6-hexanediol are excellent in the effects described later, but are also preferable from the viewpoint of industrial availability and handling properties.

That is, examples of the general polycarbonate polyol include polycarbonate diols represented by the following general formula (1).
HO — [— R—O—COO—] _n —R—OH (1)
In the formula (1), R is an aliphatic hydrocarbon group or an alicyclic hydrocarbon group, n is an integer of 2 or more, and a plurality of Rs may be the same or different. .

The polycarbonate diol is obtained, for example, by reacting one or two or more carbonate compounds selected from the group consisting of alkylene carbonate, diaryl carbonate, and dialkyl carbonate with diols and / or polyether polyols.
Examples of the alkylene carbonate include ethylene carbonate, 1,2-propylene carbonate, 1,2-butylene carbonate and the like.

  Examples of diaryl carbonates include diphenyl carbonate, phenyl-naphthyl carbonate, dinaphthyl carbonate, 4-methyl diphenyl carbonate, 4-ethyl diphenyl carbonate, 4-propyl diphenyl carbonate, 4,4'-dimethyl-diphenyl carbonate, 4,4 Examples include '-diethyl-diphenyl carbonate and 4,4'-dipropyl-diphenyl carbonate.

Examples of dialkyl carbonates include dimethyl carbonate, diethyl carbonate, di-n-propyl carbonate, diisopropyl carbonate, di-n-butyl carbonate, diisobutyl carbonate, di-t-butyl carbonate, di-n-amyl carbonate, diisoamyl carbonate. Etc.
(A-2) The polycarbonate polyol used in the present invention is essentially composed of one or more carbonate compounds selected from the group consisting of these alkylene carbonates, diaryl carbonates, and dialkyl carbonates, and 1,4-butanediol. It is obtained by reacting with diols as components, and is obtained by further reacting with diols other than 1,4-butanediol and 1,6-hexanediol and / or polyether polyols. There may be.

  In this case, other diols include ethylene glycol, 1,3-propanediol, 1,2-propanediol, 1,3-butanediol, 2,3-butanediol, 1,5-pentanediol, neopentyl. Examples include glycol, 3-methyl-1,5-pentanediol, 1,4-cyclohexanedimethanol, 1,12-dodecanediol, diethylene glycol, dipropylene glycol, and polybutadiene diol.

  Examples of polyether polyols include polytetramethylene glycol obtained by ring-opening polymerization of tetrahydrofuran and alkylene oxide adducts of diols. Examples of diols used here include, for example, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, isomer pentanediols, and isomer hexane. Diols or octanediols such as 2-ethyl-1,3-hexanediol, 1,2-bis (hydroxymethyl) -cyclohexanone, 1,3-bis (hydroxymethyl) -cyclohexanone, 1,4-bis (hydroxymethyl) ) -Cyclohexanone, trimethylolpropane, glycerin and the like, and examples of alkylene oxide include ethylene oxide, propylene oxide, 1,2-butylene oxide, 1,3-butylene oxide, 2,3-butylene oxide, tetrahydrofuran , Ji alkylene oxide, epichlorohydrin and the like, which are also possible to use a mixture of two or more.

  Among the above diols and polyether polyols, those containing 1,4-butanediol are ethylene glycol, which is a linear aliphatic diol, from the viewpoint of flexibility to develop wound repair properties, 3-propanediol, 1,5-pentanediol and 1,12-dodecanediol are preferred, and 1,5-pentanediol is preferred. The polycarbonate diol obtained by reacting 1,4-cyclohexanedimethanol, which is an alicyclic diol, becomes hard, and 1,2-propanediol, 1,3-butanediol, which are side chain aliphatic diols, Polycarbonate diol obtained by reacting 2,3-butanediol, neopentyl glycol, 3-methyl-1,5-pentanediol and polyether polyols becomes soft, and the elastic modulus of the active energy ray-curable resin composition is adjusted. Is not preferable because it becomes difficult.

  Preferred polycarbonate diols in the present invention are 1,4-butanediol, or 1,4-butanediol and 1,6-hexanediol, and when 1,6-hexanediol is present, The ratio with 1,6-hexanediol is preferably 1,4-butanediol / 1,6-hexanediol = 7/3 to 10/0 (mass ratio), 9/1 to 10/0 ( (Mass ratio) is particularly preferable. 1,4-butanediol, or 1,4-butanediol and 1,6-hexanediol are contained in the diol constituent unit of polycarbonate polyol, thereby maintaining the weather resistance, heat resistance, and hydrolysis resistance. In addition, there is an effect of improving the property, improving the breaking strength, and further improving the stain resistance and blocking resistance. However, if this ratio is out of the above range, the damage repairability and the breaking strength may be reduced. It will occur.

  When diols other than 1,4-butanediol and 1,6-hexanediol and / or polyether polyols are used in combination, if too much of these other components are used, 1,4-butanediol Alternatively, since the effects of the present invention due to the use of 1,4-butanediol and 1,6-hexanediol cannot be obtained sufficiently, it is selected from the group consisting of the aforementioned alkylene carbonates, diaryl carbonates, and dialkyl carbonates. Diols to be reacted with one or more carbonate compounds, or 50% by mass or more of diols and polyether polyols, more than 70% by mass, especially 90% by mass or more is 1,4-butanediol. Or 1,4-butanediol and 1,6-hexanediol. In particular, the (a-2) polycarbonate polyol according to the present invention includes one or two or more carbonate compounds selected from the group consisting of alkylene carbonate, diaryl carbonate, and dialkyl carbonate, 1,4-butanediol, or A polycarbonate diol obtained by reacting 1,4-butanediol with a diol composed of 1,6-hexanediol is preferred.

  The (a-2) polycarbonate polyol is preferably a high molecular weight polycarbonate polyol having a number average molecular weight of 500 or more, which improves the flaw repairability of the urethane (meth) acrylate oligomer (A) of the present invention and has a breaking strength. It is an effective ingredient for improvement. In addition, the weather resistance, heat resistance and hydrolysis resistance are not impaired as compared with other high molecular weight polyols.

  The number average molecular weight of the (a-2) polycarbonate polyol used in the present invention is a good workability due to an appropriate viscosity of the resulting urethane (meth) acrylate oligomer (A) and cures the active energy ray-curable resin composition. From the viewpoint of the mechanical strength of the cured product obtained in this manner, it is usually 500 or more, preferably 800 or more. (A-2) The number average molecular weight of the polycarbonate polyol is preferably 10,000 or less, more preferably 5000 or less, and still more preferably 2000 or less from the above viewpoint. (A-2) When the number average molecular weight of the polycarbonate diol is decreased, the workability is improved and the mechanical strength and scratch resistance tend to be improved. (A-2) When the number average molecular weight of the polycarbonate diol increases, the flexibility that can follow the deformation during three-dimensional processing of the cured product tends to decrease. (A-2) When the number average molecular weight of the polycarbonate polyol is not more than the above upper limit, the workability is good without significantly increasing the viscosity of the urethane (meth) acrylate oligomer (A), and the active energy ray curable resin. The cured product obtained by curing the composition tends to improve the mechanical strength and stain resistance, which is preferable.

  The lower limit of the hydroxyl value of (a-2) polycarbonate diol is preferably 11.2 mg-KOH / g, more preferably 22.4 mg-KOH / g, and still more preferably 56 mg-KOH / g. The upper limit is preferably 224 mg-KOH / g, more preferably 140 mg-KOH / g. When the hydroxyl value is not less than the above lower limit, the workability is good without significantly increasing the viscosity of the urethane (meth) acrylate oligomer (A), and the cured product obtained by curing the active energy ray-curable resin composition. The mechanical strength and the stain resistance tend to be improved, and it is preferable. Below the upper limit, the workability is improved and the mechanical strength and scratch resistance tend to be improved.

(A-2) Commercially available products may be used as the polycarbonate polyol. For example, Duranol T4671, T4691 (Asahi Kasei polycarbonate polyol (1,4-butanediol / 1,6-hexanediol = 7/3, 9/1) (Molar ratio), number average molecular weight = 1000) are preferred.
In the following, “(a-2) polycarbonate polyol” may be referred to as “(a-2) high molecular weight polycarbonate polyol”.
(A-3) Hydroxyalkyl (meth) acrylate (a-3) Hydroxyalkyl (meth) acrylate as a raw material compound for producing the urethane (meth) acrylate oligomer (A) in the present invention is one or more hydroxyl groups. And one or more (meth) acryloyl groups and preferably a hydrocarbon group having 1 to 30 carbon atoms. (A-3) 1 type may be used for a hydroxyalkyl (meth) acrylate, and 2 or more types may be used for it.

  (A-3) As hydroxyalkyl (meth) acrylate, for example, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) Acrylate, cyclohexanedimethanol mono (meth) acrylate, addition reaction product of 2-hydroxyethyl (meth) acrylate and caprolactone, addition reaction product of 4-hydroxybutyl (meth) acrylate and caprolactone, glycidyl ether and (meth) acrylic Examples include addition reaction products with acids, mono (meth) acrylates of glycol, pentaerythritol tri (meth) acrylate, and dipentaerythritol penta (meth) acrylate.

Among the above, the number of carbon atoms is 2 to 4 between the (meth) acryloyl group and the hydroxyl group, such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate and the like. A hydroxyalkyl (meth) acrylate having an alkylene group is particularly preferred from the viewpoint of the mechanical strength of the resulting cured film.
(A-3) The molecular weight of the hydroxyalkyl (meth) acrylate is preferably 40 or more, more preferably 80 or more, and from the viewpoint of mechanical strength of the resulting cured film, it is 800 or less, and further 400 or less. Is preferred. In addition, when (a-3) hydroxyalkyl (meth) acrylate is the above addition reactant or polymer, the molecular weight is a number average molecular weight.

Other raw material compounds The raw material compound for producing the urethane (meth) acrylate oligomer (A) in the present invention may further contain other components as long as the effects of the present invention are obtained. Examples of such other components include (a-4) a low molecular weight polyol having a molecular weight of less than 500, and (a-5) a polymer polyol having a number average molecular weight of 500 or more other than the above (a-2) high molecular weight polycarbonate polyol. (Hereinafter, it may be referred to as “(a-5) other high molecular weight polyol”) and (a-6) a chain extender.

(A-4) The low molecular weight polyol is a compound having a molecular weight of less than 500 and having two or more hydroxyl groups. 1 type may be used for a low molecular weight polyol, and 2 or more types may be used for it.
Examples of such low molecular weight polyols include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, 1,2-propanediol, 1,3-propanediol, and 2-methyl-1,3-propane. Diol, neopentyl glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 2-methyl-1,5-pentanediol, 3-methyl-1 , 5-pentanediol, 2,2,4-trimethyl-1,5-pentanediol, 2,3,5-trimethyl-1,5-pentanediol, 1,6-hexanediol, 2-ethyl-1,6 -Hexanediol, 2,2,4-trimethyl-1,6-hexanediol, 3,3 Aliphatic diols such as dimethylol heptane, 1,8-octanediol, 2-methyl-1,8-octanediol, 1,9-nonanediol; cyclopropanediol, cyclopropanedimethanol, cyclopropanediethanol, cyclopropanedi Propanol, cyclopropanedibutanol, cyclopentanediol, cyclopentanedimethanol, cyclopentanediethanol, cyclopentanedipropanol, cyclopentanedibutanol, cyclohexanediol, cyclohexanedimethanol, cyclohexanediethanol, cyclohexanedipropanol, cyclohexanedibutanol, cyclohexenediol , Cyclohexene dimethanol, cyclohexene diethanol, cyclohexene dipropanol, cyclohex Alicyclic diols such as dibutanol, cyclohexadiene diol, cyclohexadiene dimethanol, cyclohexadiene diethanol, cyclohexadiene dipropanol, cyclohexadiene dibutanol, hydrogenated bisphenol A, tricyclodecane diol, adamantyl diol; bishydroxyethoxybenzene, Aromatic diols such as bishydroxyethyl terephthalate and bisphenol-A; dialkanolamines such as N-methyldiethanolamine; pentaerythritol; sorbitol; mannitol; glycerin; and trimethylolpropane.

  Among these, from the viewpoint of the weather resistance of the obtained cured film, the (a-4) low molecular weight polyol is preferably an aliphatic diol or an alicyclic diol. In particular, in applications where the mechanical strength of the cured product is required, the low molecular weight polyol is ethylene glycol, propylene glycol, 1,2-propanediol, 1,3-propanediol, 2-methyl-1,3-propane. An aliphatic diol having 1 to 4 carbon atoms between hydroxyl groups such as diol, neopentyl glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol; 1,4-cyclohexanedimethanol, Particularly preferred is an alicyclic diol in which two hydroxyl groups such as hydrogenated bisphenol A are present at symmetrical positions with an alicyclic structure in between.

(A-4) The molecular weight of the low molecular weight polyol is preferably 50 or more from the viewpoint of the balance between the elongation and the elastic modulus as a cured product obtained by curing the active energy ray-curable resin composition, On the other hand, it is preferably 250 or less, and more preferably 150 or less.
The (a-5) other high molecular weight polyol is a compound other than a polycarbonate diol having a number average molecular weight of 500 or more and having two or more hydroxyl groups. Although there is no restriction | limiting in particular in the upper limit of the number average molecular weight of high molecular weight polyol, Usually, it is 10,000 or less. As the (a-5) other high molecular weight polyol, one type may be used, or two or more types may be used.

Examples of such (a-5) other high molecular weight polyols include polyether diols, polyester diols, polyether ester diols, polyolefin polyols, and silicon polyols, but the cured film obtained has flexibility. Polyether diol is particularly preferred from the viewpoint of imparting and improving the flaw repairability.
Examples of the polyether diol include compounds obtained by ring-opening polymerization of cyclic ethers such as polyethylene glycol, polypropylene glycol, and polytetramethylene glycol. These may use 1 type and may use 2 or more types.

  Examples of the polyester diol include compounds obtained by polycondensation of a dicarboxylic acid or its anhydride and a low molecular weight diol, such as polyethylene adipate, polypropylene adipate, polybutylene adipate, polyhexamethylene adipate, and polybutylene sebacate. Is mentioned. These may use 1 type and may use 2 or more types. Examples of the polyester diol include compounds obtained by ring-opening polymerization of a lactone with a low molecular weight diol, such as polycaprolactone and polymethylvalerolactone. These may use 1 type and may use 2 or more types.

Examples of the dicarboxylic acid include succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, fumaric acid, maleic acid, isophthalic acid, and phthalic acid. Examples of these products include these anhydrides. Examples of the low molecular weight diol include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, and polytetramethylene. Glycol, 1,5-pentanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, neopentyl glycol, 2-ethyl-1,3-hexane glycol, 2,2,4-trimethyl- Examples include 1,3-pentanediol, 3,3-dimethylolheptane, 1,9-nonanediol, 2-methyl-1,8-octanediol, cyclohexanedimethanol, and bishydroxyethoxybenzene.

Examples of the polyether ester diol include a compound obtained by ring-opening polymerization of a cyclic ether to the polyester diol, and a compound obtained by polycondensation of the polyether diol and the dicarboxylic acid, such as poly (polytetramethylene ether) adipate. Is mentioned. These may use 1 type and may use 2 or more types.
The polyolefin polyol is a polyolefin having two or more hydroxyl groups, and examples thereof include polybutadiene polyol, hydrogenated polybutadiene polyol, and polyisoprene polyol. These may use 1 type and may use 2 or more types.

The silicon polyol is a silicone having two or more hydroxyl groups, and examples of the silicon polyol include polydimethylsiloxane polyol. These may use 1 type and may use 2 or more types.
(A-6) The chain extender is a compound having two or more active hydrogens that react with an isocyanate group. One type of chain extender may be used, or two or more types may be used.

  Examples of such (a-6) chain extender include low molecular weight diamine compounds having a number average molecular weight of less than 500, such as 2,4- or 2,6-tolylenediamine, xylylenediamine, 4,4. Aromatic diamines such as' -diphenylmethanediamine; ethylenediamine, 1,2-propylenediamine, 1,6-hexanediamine, 2,2-dimethyl-1,3-propanediamine, 2-methyl-1,5-pentanediamine, 2,2,4- or 2,4,4-trimethylhexanediamine, 2-butyl-2-ethyl-1,5-pentanediamine, 1,8-octanediamine, 1,9-nonanediamine, 1,10-decane Aliphatic diamines such as diamines; and 1-amino-3-aminomethyl-3,5,5-trimethylcyclohexane (IPDA), 4 Alicyclic diamines such as 4'-dicyclohexylmethanediamine (hydrogenated MDA), isopropylidenecyclohexyl-4,4'-diamine, 1,4-diaminocyclohexane, 1,3-bisaminomethylcyclohexane, tricyclodecanediamine; Is mentioned.

[Urethane (meth) acrylate oligomer (A)]
Next, the urethane (meth) acrylate oligomer (A) of the present invention obtained from the above raw material compound and the production method thereof will be described.
In the urethane (meth) acrylate oligomer (A) of the present invention, the (a-2) polycarbonate polyol and the (a-3) high molecular weight hydroxyalkyl (meth) acrylate are added to the (a-1) polyisocyanate. It can be produced by reacting. When the other raw material compounds (a-4) low molecular weight polyol, (a-5) other high molecular weight polyol, and (a-6) chain extender are used in combination, the urethane (meth) of the present invention. The acrylate oligomer (A) can be produced by subjecting the (a-1) polyisocyanate to an addition reaction of these other raw material compounds.

In addition, the charging ratio of each raw material compound at that time is substantially equal to or the same as the composition of the target urethane (meth) acrylate oligomer (A).
These addition reactions can be performed by any known method. Examples of such a method include the following methods (a) to (c).
(A) An isocyanate-terminated urethane prepolymer obtained by reacting a component other than the hydroxyalkyl (meth) acrylate with a polyisocyanate under conditions such that an isocyanate group is excessive is obtained, and then the isocyanate-terminated urethane prepolymer and the above-mentioned A prepolymer method in which a hydroxyalkyl (meth) acrylate is reacted.
(B) One-shot method in which all raw material compounds are added simultaneously and reacted.
(C) obtained by reacting the polyisocyanate with the hydroxyalkyl (meth) acrylate first, and synthesizing a urethane (meth) acrylate prepolymer having a (meth) acryloyl group and an isocyanate group in the molecule at the same time. A method of reacting raw material compounds other than these with a prepolymer.

  Among these, according to the method (a), the urethane prepolymer is obtained by urethanation reaction of the polyisocyanate and the polycarbonate diol, and the resulting urethane (meth) acrylate oligomer has an isocyanate group at the terminal. The method (a) is preferred from the viewpoint that the molecular weight can be controlled and an acryloyl group can be introduced at both ends because the urethane prepolymer has a structure obtained by urethanation with the hydroxyalkyl (meth) acrylate.

In the urethane (meth) acrylate oligomer (A) of the present invention, the amount of all isocyanate groups and the amount of all functional groups that react with isocyanate groups such as hydroxyl groups and amino groups are usually equimolar.
That is, the (a-1) polyisocyanate, (a-2) high molecular weight polycarbonate polyol, and (a-3) hydroxyalkyl (meth) in producing the urethane (meth) acrylate oligomer (A) of the present invention. The amount of acrylate and other raw material compounds used is such that the amount of all isocyanate groups in the urethane (meth) acrylate oligomer (A) of the present invention and the amount of all functional groups reacting therewith are equimolar, or the amount relative to the isocyanate groups. The amount is 50 to 200 mol% in terms of mol% of all functional groups.

When producing the urethane (meth) acrylate oligomer (A) of the present invention, the amount of (a-3) hydroxyalkyl (meth) acrylate used is changed from (a-3) hydroxyalkyl (meth) acrylate, (a- 2) High molecular weight polycarbonate polyol, and other raw material compounds used as necessary (a-4) low molecular weight polyol, (a-5) other high molecular weight polyol, and (a-6) chain extender, etc. Usually 3 mol% or more, preferably 5 mol% or more, and usually 70 mol% or less, preferably 50 mol% or less, more preferably 30 mol, based on the total amount of the compound containing a functional group that reacts with isocyanate. % Or less. According to this ratio, the molecular weight of the urethane (meth) acrylate oligomer obtained can be controlled. When the proportion of hydroxyalkyl (meth) acrylate is large, the molecular weight of the urethane (meth) acrylate oligomer tends to be small, and when the proportion is small, the molecular weight tends to be large.

  (A-2) The total amount of (a-2) high-molecular-weight polycarbonate polyol and (a-5) other high-molecular-weight polyol used may be (a-2) 25 mol% or more of high-molecular-weight polycarbonate polyol. Preferably, it is 50 mol% or more, more preferably 70 mol% or more. (A-2) When the amount of the high-molecular-weight polycarbonate polyol used is larger than the lower limit, it is preferable because the resulting cured product tends to have good flaw repairability and hardness, scratch resistance and stain resistance.

  Moreover, with respect to the total amount of (a-2) high molecular weight polycarbonate polyol and (a-5) other high molecular weight polyols, the amount of (a-2) high molecular weight polycarbonate polyol used is 10% by mass or more. More preferably, it is 30 mass% or more, More preferably, it is 50 mass% or more, Most preferably, it is 70 mass% or more. (A-2) When the usage-amount of high molecular weight polycarbonate polyol is larger than the said lower limit, it is preferable for improving the flaw repairability and hardness, scratch resistance, and stain resistance of the resulting cured product.

  Furthermore, the total amount of (a-2) high molecular weight polycarbonate polyol, (a-5) other high molecular weight polyol, and (a-4) low molecular weight polyol, The amount used is preferably 25 mol% or more, more preferably 50 mol% or more, and still more preferably 70 mol% or more. (A-2) When the usage-amount of high molecular weight polycarbonate polyol is larger than the said lower limit, it tends to improve the flaw repairability, scratch resistance, elongation, and weather resistance of the resulting cured product.

  Further, when (a-6) a chain extender is used, (a-2) a high molecular weight polycarbonate polyol, (a-5) another high molecular weight polyol, and (a-4) a low molecular weight polyol, (A-6) The total amount of polyol used is preferably 70 mol% or more, more preferably 80 mol% or more, still more preferably 90 mol%, based on the total amount of the compound combined with the chain extender. Above, particularly preferably 95 mol% or more. When the total amount of polyol is larger than the lower limit, the liquid stability tends to be improved, which is preferable.

In addition, said raw material ratio becomes a standard at the time of manufacturing the urethane (meth) acrylate oligomer (A) of the present invention, and in fact, the below-described elastic modulus suitable for the present invention, and others It is preferable to finely adjust the raw material blending ratio in the above range so as to satisfy the above physical properties.
In the production of the urethane (meth) acrylate oligomer (A) of the present invention, a solvent can be used for the purpose of adjusting the viscosity. A solvent may be used individually by 1 type and may be used in mixture of 2 or more types. As the solvent, any known solvent can be used as long as the effects of the present invention are obtained. Preferable solvents include toluene, xylene, ethyl acetate, butyl acetate, cyclohexanone, methyl ethyl ketone, and methyl isobutyl ketone. The solvent can usually be used in an amount of less than 300 parts by mass with respect to 100 parts by mass of the solid content in the reaction system.

  In the production of the urethane (meth) acrylate oligomer (A) of the present invention, the total content of the urethane (meth) acrylate oligomer produced and the raw material compound is 20% by mass or more based on the total amount of the reaction system. It is preferable that it is 40 mass% or more. In addition, the upper limit of this total content is 100 mass%. It is preferable for the total content of the urethane (meth) acrylate oligomer and its raw material compound to be 20% by mass or more because the reaction rate tends to increase and the production efficiency tends to improve.

  An addition reaction catalyst can be used in the production of the urethane (meth) acrylate oligomer (A) of the present invention. The addition reaction catalyst can be selected from the range in which the effects of the present invention can be obtained, and examples thereof include dibutyltin laurate, dibutyltin dioctoate, dioctyltin dilaurate, and dioctyltin dioctoate. An addition reaction catalyst may be used individually by 1 type, and 2 or more types may be mixed and used for it. Of these, the addition reaction catalyst is preferably dioctyltin dilaurate from the viewpoints of environmental adaptability, catalytic activity, and storage stability.

The addition reaction catalyst has an upper limit of usually 1000 ppm or less, preferably 500 ppm or less, and a lower limit of usually 10 ppm or more, preferably 30 ppm or more, with respect to the total content of the urethane (meth) acrylate oligomer to be produced and its raw material compounds. Used.
Moreover, when the (meth) acryloyl group is included in the reaction system during the production of the urethane (meth) acrylate oligomer (A) of the present invention, a polymerization inhibitor can be used in combination. Such a polymerization inhibitor can be selected from the range in which the effects of the present invention can be obtained, for example, phenols such as hydroquinone, methylhydroquinone, hydroquinone monoethyl ether, dibutylhydroxytoluene, amines such as phenothiazine and diphenylamine, Examples thereof include copper salts such as copper dibutyldithiocarbamate, manganese salts such as manganese acetate, nitro compounds, and nitroso compounds. A polymerization inhibitor may be used individually by 1 type, and 2 or more types may be mixed and used for it. Of these, phenols are preferable as the polymerization inhibitor.

The polymerization inhibitor has an upper limit of usually 3000 ppm or less, preferably 1000 ppm or less, particularly preferably 500 ppm or less, and a lower limit usually based on the total content of the urethane (meth) acrylate oligomer and raw material compounds to be produced. It is used at 50 ppm or more, preferably 100 ppm or more.
In the production of the urethane (meth) acrylate oligomer (A) of the present invention, the reaction temperature is usually 20 ° C. or higher, preferably 40 ° C. or higher, and more preferably 60 ° C. or higher. A reaction temperature of 20 ° C. or higher is preferable because the reaction rate increases and the production efficiency tends to improve. Moreover, reaction temperature is 120 degrees C or less normally, and it is preferable that it is 100 degrees C or less. It is preferable for the reaction temperature to be 120 ° C. or lower because side reactions such as an allohanato reaction hardly occur. When the reaction system contains a solvent, the reaction temperature is preferably lower than the boiling point of the solvent. When (meth) acrylate is contained, the reaction temperature is 70 ° C. from the viewpoint of preventing the reaction of the (meth) acryloyl group. The following is preferable. The reaction time is usually about 5 to 20 hours.

  The urethane (meth) acrylate oligomer thus obtained has a number average molecular weight of 500 or more, particularly 1000 or more, particularly 3000 or more, preferably 15000 or less, particularly preferably 10,000 or less. When the number average molecular weight of the urethane (meth) acrylate oligomer is not less than the above lower limit, the resulting cured film has good three-dimensional processability and tends to have a good balance between three-dimensional processability, scratch repairability, and stain resistance. It is preferable. When the number average molecular weight of the urethane (meth) acrylate oligomer is not more than the above upper limit, the cured film obtained from the composition has good stain resistance, and the balance between three-dimensional processability, flaw repairability and stain resistance is good. This is preferable because it tends to be excellent. This is because the three-dimensional workability and stain resistance depend on the distance between the cross-linking points in the network structure, and as this distance increases, the structure becomes flexible and easily stretched, and the three-dimensional workability is superior. This is presumed to be because the structure becomes a strong structure and is excellent in stain resistance.

The urethane bond amount of the urethane (meth) acrylate oligomer (A) of the present invention is preferably 5 to 25% by mass, particularly preferably 10 to 20% by mass. When the urethane bond amount is not less than the above lower limit, the mechanical strength and the stain resistance tend to be improved, and when it is not more than the above upper limit, the flaw repairability and the elongation tend to be improved.
In addition, the urethane bond amount of a urethane (meth) acrylate-type oligomer can be calculated | required by the method described in the term of the below-mentioned Example.

The amount of urethane bonds can be controlled by adjusting the raw material composition of the urethane (meth) acrylate oligomer (A).
[Active energy ray-curable resin composition]
Below, the active energy ray-curable resin composition of the present invention containing the urethane (meth) acrylate oligomer (A) described above will be described.

The active energy ray-curable resin composition of the present invention preferably has a molecular weight between calculated network crosslinking points of 1,000 to 15,000.
In the present specification, the molecular weight between calculated network cross-linking points of the composition is the average molecular weight between active energy ray reactive groups (hereinafter sometimes referred to as “cross-linking points”) that form a network structure in the entire composition. Represents a value. The molecular weight between the calculated network crosslinking points correlates with the network area at the time of forming the network structure, and the larger the calculated molecular weight between the crosslinking points, the lower the crosslinking density. In the reaction by active energy ray curing, when a compound having only one active energy ray reactive group (hereinafter, sometimes referred to as “monofunctional compound”) reacts, it becomes a linear polymer, while the active energy A network structure is formed when a compound having two or more linear reactive groups (hereinafter sometimes referred to as “polyfunctional compound”) reacts.

  Therefore, the active energy ray reactive group of the polyfunctional compound is a crosslinking point, and the calculation of the molecular weight between the calculated network crosslinking points is centered on the polyfunctional compound having the crosslinking point, and the monofunctional compound has the polyfunctional compound. The molecular weight between the crosslinking points is treated as having an effect of extending the molecular weight, and the molecular weight between the calculation network crosslinking points is calculated. In addition, the calculation of the molecular weight between the calculation network crosslinking points is performed on the assumption that all the active energy ray reactive groups have the same reactivity and that all the active energy ray reactive groups react by irradiation with the active energy ray. .

In a polyfunctional compound single-system composition in which only one type of polyfunctional compound reacts, the molecular weight between the calculated network cross-linking points is twice the average molecular weight per active energy ray reactive group of the polyfunctional compound. . For example, (1000/2) × 2 = 1000 for a bifunctional compound with a molecular weight of 1,000, and (300/3) × 2 = 200 for a trifunctional compound with a molecular weight of 300.
In a polyfunctional compound mixed system composition in which multiple types of polyfunctional compounds react, the average value of the molecular weights between the calculated network cross-linking points of each of the above single systems with respect to the total number of active energy ray reactive groups contained in the composition is This is the molecular weight between the calculated network crosslinking points of the composition. For example, in a composition comprising a mixture of 4 moles of a bifunctional compound having a molecular weight of 1,000 and 4 moles of a trifunctional compound having a molecular weight of 300, the total number of reactive energy ray reactive groups in the composition is 2 × 4 + 3 × 4 = 20. The molecular weight between the calculated network cross-linking points of the composition is {(1000/2) × 8 + (300/3) × 12} × 2/20 = 520.

  When a monofunctional compound is included in the composition, a molecule formed by calculation and equimolar to the active energy ray reactive group (that is, the crosslinking point) of the polyfunctional compound, and the monofunctional compound linked to the crosslinking point Assuming that the reaction takes place in the middle of the chain, the extension of the molecular chain by the monofunctional compound at one crosslinking point is the total molecular weight of the monofunctional compound, and the total active energy ray reaction of the polyfunctional compound in the composition. Half of the value divided by the radix. Here, since the molecular weight between the calculated network cross-linking points is considered to be twice the average molecular weight per cross-linking point, the amount extended by the monofunctional compound relative to the calculated molecular weight between the cross-linking points calculated for the polyfunctional compound is The value obtained by dividing the total molecular weight of the monofunctional compound by the total number of reactive energy ray reactive groups of the polyfunctional compound in the composition.

  For example, in a composition comprising a mixture of 40 mol of a monofunctional compound having a molecular weight of 100 and 4 mol of a bifunctional compound having a molecular weight of 1,000, the number of reactive energy ray reactive groups of the polyfunctional compound is 2 × 4 = 8. The extension due to the monofunctional compound in the molecular weight between the calculated network cross-linking points is 100 × 40/8 = 500. That is, the molecular weight between calculated network crosslinks of the composition is 1000 + 500 = 1500.

From the above, in the mixture of monofunctional compounds M _A molar molecular weight W _A, and f _B functional compound M _B mol molecular weight W _B, and f _C functional compound M _C mol molecular weight W _C, the composition The molecular weight between the calculated network cross-linking points of the product can be expressed by the following formula.

  The molecular weight between calculated network crosslinking points of the active energy ray-curable resin composition of the present invention calculated in this way is preferably 1000 or more, more preferably 2,000 or more, and 3000 or more. More preferably, it is 4000 or more, particularly preferably 15,000 or less, more preferably 12000 or less, and particularly preferably 10,000 or less.

  When the molecular weight between calculated network cross-linking points is 15,000 or less, the cured film obtained from the composition has good stain resistance, and tends to have a good balance between three-dimensional processability, scratch repairability, and stain resistance. Therefore, it is preferable. Further, if the molecular weight between the calculated network cross-linking points is 1,000 or more, the resulting cured film has good three-dimensional workability and tends to have an excellent balance between three-dimensional workability, scratch repairability, and stain resistance. . This is because the three-dimensional workability and stain resistance depend on the distance between the cross-linking points in the network structure. When this distance is increased, the structure becomes flexible and easily stretched, and the three-dimensional processability is excellent. This is presumed to be because the structure becomes a strong structure and is excellent in stain resistance.

Moreover, when the molecular weight between the calculated network cross-linking points is in the range of 1,000 to 15,000, it is easy to obtain an active energy ray-curable resin composition that can satisfy the elastic modulus described later, and is excellent in self-healing properties. A cured film can be obtained.
As a method of adjusting the molecular weight between the calculation network cross-linking points, for example, the number average molecular weight of the urethane (meth) acrylate oligomer can be lowered, or it can be lowered by adding a polyfunctional acrylate.

  The active energy ray-curable resin composition of the present invention may further contain other components other than the urethane (meth) acrylate-based oligomer (A) of the present invention as long as the effects of the present invention are obtained. Examples of such other components include an active energy ray-reactive monomer, an active energy ray-curable oligomer, a polymerization initiator, a photosensitizer, an epoxy compound, an additive, and a solvent.

  In the active energy ray-curable resin composition of the present invention, the content of the urethane (meth) acrylate oligomer (A) of the present invention is an active energy ray reaction containing the urethane (meth) acrylate oligomer (A) of the present invention. The content is preferably 40% by mass or more, more preferably 60% by mass or more, based on the total amount of the sex component. In addition, the upper limit of this content is 100 mass%. When the content of the urethane (meth) acrylate oligomer (A) is 40% by mass or more, the curability is good and the three-dimensional workability is improved without excessively increasing the mechanical strength of the cured product. This is preferable.

Moreover, in the active energy ray-curable resin composition of the present invention, the content of the urethane (meth) acrylate oligomer (A) of the present invention is preferably larger in terms of elongation and film-forming property. In terms of lowering the viscosity, a smaller amount is preferable. From such a viewpoint, the content of the urethane (meth) acrylate oligomer (A) of the present invention is 50% by mass with respect to the total amount of all components including other components in addition to the active energy ray reactive component. The above is preferable, and 70% by mass or more is more preferable. In addition, the upper limit of content of the urethane (meth) acrylate oligomer (A) of this invention is 100 mass%, and it is preferable that this content is less than that.

  Moreover, in the active energy ray-curable resin composition of the present invention, the total content of the active energy ray-reactive component containing the urethane (meth) acrylate oligomer (A) of the present invention is a curing rate as a composition. From the viewpoint of excellent surface curability and no tack remaining, it is preferably 60% by mass or more, more preferably 80% by mass or more, and more preferably 90% by mass or more based on the total amount of the composition. More preferably, it is 95% by mass or more. In addition, the upper limit of this content is 100 mass%.

  Any known active energy ray-reactive monomer can be used as the active energy ray-reactive monomer as long as the effects of the present invention are obtained. These active energy ray reactive monomers have properties such as the hydrophilicity / hydrophobicity of the urethane (meth) acrylate oligomer (A) of the present invention and the hardness and elongation of the cured product when the resulting composition is a cured product. Used for adjustment purposes. An active energy ray reactive monomer may be used individually by 1 type, and 2 or more types may be mixed and used for it.

Examples of such active energy ray reactive monomers include vinyl ethers, (meth) acrylamides, and (meth) acrylates. Specific examples include styrene, α-methylstyrene, α-chlorostyrene. Aromatic vinyl monomers such as vinyltoluene and divinylbenzene; vinyl such as vinyl acetate, vinyl butyrate, N-vinylformamide, N-vinylacetamide, N-vinyl-2-pyrrolidone, N-vinylcaprolactam and divinyl adipate Ester monomers; Vinyl ethers such as ethyl vinyl ether and phenyl vinyl ether; Allyl compounds such as diallyl phthalate, trimethylolpropane diallyl ether, and allyl glycidyl ether; (meth) acrylamide, N, N-dimethylacrylamide N, N-dimethylmethacrylamide, N-methylol (meth) acrylamide, N-methoxymethyl (meth) acrylamide, N-butoxymethyl (meth) acrylamide, Nt-butyl (meth) acrylamide, (meth) acryloylmorpholine (Meth) acrylamides such as methylenebis (meth) acrylamide; (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, (meth) acrylate-n-butyl , (Meth) acrylic acid-i-butyl, (meth) acrylic acid-t-butyl, (meth) acrylic acid hexyl, (meth) acrylic acid-2-ethylhexyl, (meth) acrylic acid lauryl, (meth) acrylic acid Stearyl, tetrahydrofurfuryl (meth) acrylate, (meth) a Morpholyl laurate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, glycidyl (meth) acrylate, dimethyl (meth) acrylate Aminoethyl, diethylaminoethyl (meth) acrylate, benzyl (meth) acrylate, cyclohexyl (meth) acrylate, phenoxyethyl (meth) acrylate, tricyclodecane (meth) acrylate, dicyclopentenyl (meth) acrylate , (Meth) acrylic acid dicyclopentenyloxyethyl, (meth) acrylic acid dicyclopentanyl, (meth) acrylic acid allyl, (meth) acrylic acid-2-ethoxyethyl, (meth) acrylic acid isobornyl, (meth) Monofunctional (meth) acrylic acid such as phenyl acrylate And ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate ( n = 5-14), propylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, tetrapropylene glycol di (meth) acrylate, di (meth) Polypropylene glycol acrylate (n =
5-14), di (meth) acrylic acid-1,3-butylene glycol, di (meth) acrylic acid-1,4-butanediol, di (meth) acrylic acid polybutylene glycol (n = 3 to 16), Di (meth) acrylic acid poly (1-methylbutylene glycol) (n = 5 to 20), di (meth) acrylic acid-1,6-hexanediol, di (meth) acrylic acid-1,9-nonanediol, Di (meth) acrylate neopentyl glycol, hydroxypivalate neopentyl glycol di (meth) acrylate, di (meth) acrylate dicyclopentanediol, di (meth) acrylate tricyclodecane, trimethylolpropane tri ( (Meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) a Relate, ditrimethylolpropane tetra (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, trimethylolpropane trioxyethyl (meth) acrylate, tri Methylolpropane trioxypropyl (meth) acrylate, trimethylolpropane polyoxyethyl (meth) acrylate, trimethylolpropane polyoxypropyl (meth) acrylate, tris (2-hydroxyethyl) isocyanurate tri (meth) acrylate, tris (2 -Hydroxyethyl) isocyanurate di (meth) acrylate, ethylene oxide-added bisphenol A di (meth) acrylate, ethyl Oxide-added bisphenol F di (meth) acrylate, propylene oxide-added bisphenol A di (meth) acrylate, propylene oxide-added bisphenol F di (meth) acrylate, tricyclodecane dimethanol di (meth) acrylate, bisphenol A epoxy di (meth) Polyfunctional (meth) acrylates such as acrylate and bisphenol F epoxy di (meth) acrylate;

  Among these, in particular, in applications where coating properties are required for the composition of the present invention, (meth) acryloylmorpholine, tetrahydrofurfuryl (meth) acrylate, benzyl (meth) acrylate, cyclohexyl (meth) acrylate , Molecules such as trimethylcyclohexyl (meth) acrylate, phenoxyethyl (meth) acrylate, tricyclodecane (meth) acrylate, dicyclopentenyl (meth) acrylate, isobornyl (meth) acrylate, (meth) acrylamide, etc. A monofunctional (meth) acrylate having a ring structure in the inside thereof is preferable. On the other hand, in applications where mechanical strength of the resulting cured product is required, di (meth) acrylic acid-1,4-butanediol, di (meth) ) Acrylic acid-1,6-hexanediol, di (meth) acrylic acid-1,9-nonane Dipentaglycol di (meth) acrylate, tricyclodecane di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipenta Multifunctional (meth) acrylates such as erythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, and dipentaerythritol hexa (meth) acrylate are preferred, and in applications where flexibility of the resulting cured product is required, di ( Poly (ethylene glycol) acrylate (n = 5-14), polypropylene glycol di (meth) acrylate (n = 5-14), poly (butylene glycol di (meth) acrylate (n = 3-16), di (meth) )acrylic Poly (1-methyl-butylene glycol) (n = 5 to 20) Polyether (meth) acrylates are preferable.

  In the active energy ray-curable resin composition of the present invention, the content of the active energy ray-reactive monomer is selected from the viewpoints of adjusting the viscosity of the composition and adjusting physical properties such as hardness and elongation of the resulting cured product. It is preferably 50% by mass or less, more preferably 30% by mass or less, still more preferably 20% by mass or less, and still more preferably 10% by mass or less, based on the total amount of the object.

The active energy ray-curable oligomer may be used alone or in combination of two or more. Examples of the active energy ray-curable oligomer include epoxy (meth) acrylate oligomers and acrylic (meth) acrylate oligomers.
In the active energy ray-curable resin composition of the present invention, the content of the active energy ray-reactive oligomer is based on the total amount of the composition from the viewpoint of adjusting physical properties such as hardness and elongation of the obtained cured product. It is preferably 50% by mass or less, more preferably 30% by mass or less, further preferably 20% by mass or less, and further more preferably 10% by mass or less.

  The polymerization initiator is mainly used for the purpose of improving the initiation efficiency of a polymerization reaction that proceeds by irradiation with active energy rays such as ultraviolet rays and electron beams. As the polymerization initiator, a photoradical polymerization initiator which is a compound having a property of generating radicals by light is generally used, and any known photoradical polymerization initiator can be used as long as the effects of the present invention can be obtained. It is. A polymerization initiator may be used individually by 1 type, and 2 or more types may be mixed and used for it. Furthermore, you may use together radical photopolymerization initiator and a photosensitizer.

  Examples of the photo radical polymerization initiator include benzophenone, 2,4,6-trimethylbenzophenone, 4,4-bis (diethylamino) benzophenone, 4-phenylbenzophenone, methylorthobenzoylbenzoate, thioxanthone, diethylthioxanthone, isopropylthioxanthone, chloro Thioxanthone, 2-ethylanthraquinone, t-butylanthraquinone, diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzyldimethyl ketal, 1-hydroxycyclohexyl phenyl ketone, benzoin methyl ether, benzoin ethyl Ether, benzoin isopropyl ether, benzoin isobutyl ether, methylbenzoylformate, 2-methyl-1- [4- ( Tilthio) phenyl] -2-morpholinopropan-1-one, 2,6-dimethylbenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis (2,6-dimethoxybenzoyl) -2,4 4-trimethylpentylphosphine oxide, bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide, and 2-hydroxy-1- [4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl]- Phenyl] -2-methyl-propan-1-one and the like.

  Among these, benzophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2,4,6, since the curing speed is high and the crosslinking density can be sufficiently increased. -Trimethylbenzoyldiphenylphosphine oxide and 2-hydroxy-1- [4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] -phenyl] -2-methyl-propan-1-one 1-hydroxycyclohexyl phenyl ketone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, and 2-hydroxy-1- [4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] -phenyl ] 2-Methyl-propan-1-one is more preferred.

In addition, when the active energy ray-curable resin composition includes a compound having a cationic polymerizable group such as an epoxy group together with a radical polymerizable group, as a polymerization initiator, photo cationic polymerization together with the above-described photo radical polymerization initiator is used. An initiator may be included. Any known cationic photopolymerization initiator can be used as long as the effects of the present invention can be obtained.
The content of these polymerization initiators in the active energy ray-curable resin composition of the present invention is preferably 10 parts by mass or less with respect to 100 parts by mass in total of the active energy ray reactive components. It is more preferable that the amount is not more than part by mass. It is preferable for the content of the photopolymerization initiator to be 10 parts by mass or less because the mechanical strength is not easily lowered by the initiator decomposition product.

  The photosensitizer can be used for the same purpose as the polymerization initiator. A photosensitizer may be used individually by 1 type and may be used in mixture of 2 or more types. As the photosensitizer, any known photosensitizer can be used as long as the effects of the present invention are obtained. Examples of such photosensitizers include ethanolamine, diethanolamine, triethanolamine, N-methyldiethanolamine, methyl 4-dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate, amyl 4-dimethylaminobenzoate, And 4-dimethylaminoacetophenone.

In the active energy ray-curable resin composition of the present invention, the content of the photosensitizer is preferably 10 parts by mass or less with respect to a total of 100 parts by mass of the active energy ray reactive components. More preferably, it is 5 parts by mass or less. It is preferable for the content of the photosensitizer to be 10 parts by mass or less, since it is difficult for mechanical strength to decrease due to a decrease in crosslink density.
When the epoxy compound is a laminate having a cured film formed using the active energy ray-curable resin composition of the present invention, and a chlorine-based component is contained in a layer adjacent to the cured film, As this chlorinated component migrates to the cured film, the cured film deteriorates (yellows), so it is blended as necessary to capture the chlorine component and improve the heat resistance and weather resistance of the cured film. Is done.

As this epoxy compound, an epoxy group-containing acrylic resin, an epoxy group-containing vinyl resin or the like can be used, and these may be used alone or in combination of two or more.
When the active energy ray-curable resin composition of the present invention contains an epoxy compound, the content thereof is preferably 10 parts by mass or less with respect to a total of 100 parts by mass of the active energy ray reactive components. The amount is more preferably 5 parts by mass or less, and particularly preferably 3 parts by mass or less. If the content of the epoxy compound is too large, it is not preferable because the adverse effects on the other performance such as mechanical strength, scratch repairability, hardness and stain resistance due to the introduction of functional groups are reduced.

  The additive is optional as long as the effects of the present invention are obtained, and various materials added to a composition used for the same application can be used as the additive. An additive may be used individually by 1 type, and 2 or more types may be mixed and used for it. Examples of such additives include glass fiber, glass bead, silica, alumina, calcium carbonate, mica, zinc oxide, titanium oxide, mica, talc, kaolin, metal oxide, metal fiber, iron, lead, and metal powder. Fillers such as carbon fibers, carbon black, graphite, carbon nanotubes, carbon materials such as fullerenes such as C60 (fillers and carbon materials may be collectively referred to as “inorganic components”); Agent, heat stabilizer, UV absorber, HALS (hindered amine light stabilizer), anti-fingerprint agent, surface hydrophilizing agent, antistatic agent, slipperiness imparting agent, plasticizer, mold release agent, antifoaming agent, leveling agent, Anti-settling agents, surfactants, thixotropy imparting agents, lubricants, flame retardants, flame retardant aids, polymerization inhibitors, fillers, silane coupling agents and other modifiers; pigments, dyes, hue adjustments Colorants and the like; and, monomer and / or oligomer thereof, or a curing agent required for the synthesis of inorganic components, catalysts, curing accelerators like; and the like.

In the active energy ray-curable resin composition of the present invention, the content of the additive is preferably 10 parts by mass or less with respect to a total of 100 parts by mass of the active energy ray-reactive components. It is more preferable that the amount is not more than parts. It is preferable for the content of the additive to be 10 parts by mass or less, since it is difficult for mechanical strength to decrease due to a decrease in crosslink density.
The solvent is used for the purpose of adjusting the viscosity of the active energy ray-curable resin composition of the present invention, for example, depending on the coating method for forming the coating film of the active energy ray-curable resin composition of the present invention. be able to. A solvent may be used individually by 1 type and may be used in mixture of 2 or more types. As the solvent, any known solvent can be used as long as the effects of the present invention are obtained. Preferable solvents include toluene, xylene, ethyl acetate, butyl acetate, isopropanol, isobutanol, cyclohexanone, methyl ethyl ketone, and methyl isobutyl ketone. A solvent can be normally used in less than 200 mass parts with respect to 100 mass parts of solid content of an active energy ray curable resin composition.

  There are no particular limitations on the method of incorporating the optional components such as the aforementioned additives into the active energy ray-curable resin composition of the present invention, and conventionally known mixing and dispersion methods and the like can be mentioned. In addition, in order to disperse | distribute the said arbitrary component more reliably, it is preferable to perform a dispersion | distribution process using a disperser. Specifically, for example, two rolls, three rolls, bead mill, ball mill, sand mill, pebble mill, tron mill, sand grinder, seg barrier striker, planetary stirrer, high speed impeller disperser, high speed stone mill, high speed impact mill , A kneader, a homogenizer, an ultrasonic disperser and the like.

  The viscosity of the active energy ray-curable resin composition of the present invention can be appropriately adjusted according to the use and usage of the composition, but from the viewpoints of handleability, coatability, moldability, three-dimensional formability, etc. The viscosity at 25 ° C. in an E-type viscometer (rotor 1 ° 34 ′ × R24) is preferably 10 mPa · s or more, more preferably 30 mPa · s or more, and 50,000 mPa on the other hand. It is preferably s or less, more preferably 10,000 mPa · s or less, still more preferably 5,000 mPa · s or less, and particularly preferably 2,000 mPa · s or less. The viscosity of the active energy ray-curable resin composition can be adjusted by, for example, the content of the urethane (meth) acrylate oligomer (A) of the present invention, the type of the optional component, the blending ratio thereof, and the like.

  As a coating method of the active energy ray-curable resin composition of the present invention, a bar coater method, an applicator method, a curtain flow coater method, a roll coater method, a spray method, a gravure coater method, a comma coater method, a reverse roll coater method, Known methods such as a lip coater method, a die coater method, a slot die coater method, an air knife coater method, and a dip coater method can be applied, and among them, a bar coater method and a gravure coater method are preferable.

[Tensile modulus]
The active energy ray-curable resin composition of the present invention has a tensile modulus measured by the following method of 100 for a cured film formed by the following method using the active energy ray-curable resin composition. It is -1000 MPa. Good self-repairing properties can be obtained when the tensile modulus is 100 to 1000 MPa or less. If the tensile modulus is less than 100 MPa, the cured film surface is too sticky and the friction coefficient increases, so that the load on the cured film surface increases and the wound may not be repaired. On the other hand, if it exceeds 1000 MPa, the cured film is too hard, so that it is impossible to disperse the load due to elasticity, and the wound cannot be repaired. This tensile elastic modulus is more preferably 120 to 500 MPa, further preferably 140 to 400 MPa, and particularly preferably 150 to 350 MPa.

<Film forming method>
An active energy ray-curable resin composition is coated on a polyethylene terephthalate film with a bar coater to form a coating film, and then dried at 60 ° C. for 1 minute, using an electron beam irradiation device (CB175, manufactured by iGraphic). Then, after irradiating the dried coating film with an electron beam under the conditions of an acceleration voltage of 165 kV and an irradiation dose of 5 Mrad, and further curing at 23 ° C. for one day to form a cured film, the cured film is peeled off from the polyethylene terephthalate film. A cured film of about 20 μm is obtained.

<Tensile modulus measurement method>
The cured film was cut into a width of 10 mm, and using a Tensilon tensile tester ("RTC-1210A" manufactured by Orientec Co., Ltd.), the temperature was 23 ° C, the humidity was 55% RH, the tensile speed was 50 mm / min, and the distance between chucks was 50 mm. The tensile elastic modulus is measured by performing a tensile test.
More specifically, a straight line connecting the stress at 0% elongation and the stress at 0.5% elongation of the stress-strain curve (SS curve) obtained by conducting the tensile test under the above conditions is extended to 100 The stress converted at% elongation was taken as the tensile modulus.

The tensile elastic modulus of the active energy ray-curable resin composition can be controlled by adjusting the type and amount ratio of the raw material compound used for producing the urethane (meth) acrylate oligomer.
For example, the elastic modulus can be increased by using (a-4) a low molecular weight polyol. In adjusting the elastic modulus, (a-2) high molecular weight polycarbonate polyol and (a-4) low molecular weight polyol are (a-4) low molecular weight polyol / (a-2) high molecular weight polycarbonate polyol 50 / 50-0 / 100
It is preferable to use within the range of (mass ratio). In addition, the elastic modulus can be lowered by using a polyether polyol which is (a-5) other high molecular weight polyol and / or a polyether (meth) acrylate which is an active energy ray reactive monomer.

[Curing film and laminate]
The active energy ray-curable resin composition of the present invention can be made into a cured film by irradiating this with active energy rays.
As the active energy rays used when the composition is cured, infrared rays, visible rays, ultraviolet rays, X-rays, electron beams, α rays, β rays, γ rays and the like can be used. It is preferable to use an electron beam or an ultraviolet ray from the viewpoint of apparatus cost and productivity. As a light source, an electron beam irradiation apparatus, an ultrahigh pressure mercury lamp, a high pressure mercury lamp, a medium pressure mercury lamp, a low pressure mercury lamp, a metal halide lamp, Ar Lasers, He—Cd lasers, solid lasers, xenon lamps, high frequency induction mercury lamps, sunlight, and the like are suitable.

The irradiation amount of the active energy ray can be appropriately selected according to the type of the active energy ray. For example, when curing is performed by electron beam irradiation, the irradiation amount is preferably 1 to 10 Mrad. Moreover, in the case of ultraviolet irradiation, it is preferable that it is 50-1,000 mJ / cm < ² >. The atmosphere during curing may be air, an inert gas such as nitrogen or argon. Moreover, you may irradiate in the sealed space between a film or glass, and a metal metal mold | die.

  The thickness of the cured film of the present invention is appropriately determined according to the intended use, but the lower limit is preferably 1 μm, more preferably 3 μm, and particularly preferably 5 μm. The upper limit is preferably 200 μm, more preferably 100 μm, particularly preferably 50 μm. When the film thickness is 1 μm or more, the design properties and functionality after three-dimensional processing are improved, and when it is 200 μm or less, the internal curability and the three-dimensional workability are preferable. In industrial use, the lower limit is preferably 1 μm, more preferably 5 μm, and particularly preferably 10 μm. The upper limit is preferably 100 μm, more preferably 50 μm.

According to this invention, the laminated body which has a layer which consists of said cured film of this invention on a base material can be obtained.
The laminate of the present invention is not particularly limited as long as it has a layer comprising the cured film of the present invention, and a layer other than the substrate and the cured film of the present invention is interposed between the substrate and the cured film of the present invention. You may have, and you may have on the outer side. Moreover, the said laminated body may have multiple layers of the base material and the cured film of this invention.

  As a method for obtaining the laminate of the present invention having a multi-layered cured film, all layers are laminated in an uncured state and then cured with active energy rays, the lower layer is cured with active energy rays, or semi-cured A method in which the upper layer is applied and then cured with active energy rays, a method in which each layer is applied to a release film or a base film, and then the layers are bonded together in an uncured or semi-cured state. Although a method is applicable, the method of hardening with an active energy ray after laminating | stacking in an uncured state from a viewpoint of improving the adhesiveness of an interlayer is preferable. As a method of laminating in an uncured state, a known method such as sequential coating in which the upper layer is applied after the lower layer is applied or simultaneous multilayer coating in which two or more layers are simultaneously applied from multiple slits is applied. Yes, but not necessarily.

Examples of the base material include various shapes such as polyesters such as polyethylene terephthalate and polybutylene terephthalate, polyolefins such as polypropylene and polyethylene, various plastics such as nylon, polycarbonate, and (meth) acrylic resin, or plates formed of metal. The article is mentioned.
The cured film of the present invention can be a film having excellent stain resistance and hardness against general household contaminants such as ink and ethanol, and the present invention using the cured film of the present invention as a coating on various substrates. The laminate can be excellent in design and surface protection.

In addition, the active energy ray-curable resin composition of the present invention has flexibility, flaw repairability, elongation at break, mechanical strength capable of following deformation during three-dimensional processing, taking into consideration the molecular weight between calculated network cross-linking points. Further, a cured film having both contamination resistance and hardness can be provided.
Moreover, it is expected that the active energy ray-curable resin composition of the present invention can easily produce a thin film-like resin sheet by applying a single layer.

  The breaking elongation of the cured film of the present invention was determined by cutting the cured film of the present invention into a width of 10 mm and using a Tensilon tensile tester ("RTC-1210A" manufactured by Orientec Co., Ltd.) at a temperature of 23 ° C and a relative humidity of 55%. The value measured by conducting a tensile test under the conditions of a tensile speed of 50 mm / min and a distance between chucks of 50 mm is preferably 50% or more, more preferably 75% or more, and more preferably 100% or more. More preferably, it is particularly preferably 125% or more.

The cured film of the present invention and the laminate of the present invention can be used as a coating substitute film, and are effectively applied to various materials such as interior and exterior building materials, automobiles, home appliances, information electronic materials, and the like. It is possible.
In particular, the cured film of the present invention is useful as a decorative film using this as a top coat layer.

<Reason why the present invention is effective>
Although the reason why the present invention is effective is not yet clear, it is presumed as follows.
The flaw repairability is manifested by preventing bond breakage by dispersing stress by plastic deformation of the cured film and restoring to a minimum energy state over time. Resin that is easily plastically deformed is synonymous with low resistance to stress, and can be expressed as low elastic modulus. That is, a resin having a lower modulus of elasticity is superior in scratch repairability. However, if the elastic modulus becomes too low, other properties required for the cured film such as contamination resistance, blocking resistance, weather resistance, etc. are impaired.

The three-dimensional followability is effective because it does not cause bond breakage due to stress on the cured film that occurs during stretching of the cured film. Therefore, a resin having a large network area of the cured film, that is, a resin having a high molecular weight between calculated network cross-linking points, is excellent in three-dimensional followability. However, if the molecular weight between the calculation network cross-linking points becomes too high, other properties required for the cured film such as stain resistance, blocking resistance, weather resistance, etc. are impaired.

Specific examples of the present invention will be described in more detail below with reference to examples and comparative examples. However, the present invention is not limited by these examples unless it exceeds the gist.
[Measurement and evaluation methods for various physical properties and characteristic values]
<Calculation method of number average molecular weight of urethane (meth) acrylate oligomer>
The urethane (meth) acrylate oligomers of the examples and comparative examples contain three types of components, polyisocyanate, polycarbonate diol, and hydroxyalkyl (meth) acrylate, as constituent units. Since these structural units are formed while maintaining the molecular weight of each component in the urethane (meth) acrylate oligomer, in this example and the comparative example, until the urethane (meth) acrylate oligomer is generated. The number average molecular weight (calculated value) of the urethane (meth) acrylate oligomer was calculated by the sum of the product of the molar ratio of each component (hydroxyalkyl (meth) acrylate is calculated by 2) and the molecular weight of each component.

<Measurement of number average molecular weight of urethane (meth) acrylate oligomer by GPC>
Using GPC (“HLC-8120GPC” manufactured by Tosoh Corporation), THF as a solvent, polystyrene as a standard sample, TSKgel superH1000 + H2000 + H3000 as a column, a liquid feed rate of 0.5 mL / min, a column oven temperature of 40 ° C., urethane ( The number average molecular weight (GPC measurement value) of the (meth) acrylate oligomer was measured.

<Calculation of molecular weight between calculation network crosslinking points of active energy ray curable resin composition>
The molecular weight between the calculated network cross-linking points of the urethane (meth) acrylate oligomer in each example and comparative example is that the reactive groups for the hydroxyalkyl (meth) acrylate in the prepolymer of the urethane acrylate oligomer are isocyanate groups at both ends of the prepolymer. Yes, since the hydroxyalkyl (meth) acrylate bonded with urethane bonds to both ends of the prepolymer is added by radical polymerization, the crosslinking point of the urethane acrylate oligomer in the composition is both the urethane (meth) acrylate oligomer Since it becomes a (meth) acryloyl group located at the terminal, and in the following Examples and Comparative Examples, the active energy ray-curable resin composition becomes the above-described bifunctional (polyfunctional) compound single-system composition, It was obtained from the formula of

<Urethane bond amount of urethane (meth) acrylate oligomer>
The urethane (meth) acrylate oligomers of the examples and comparative examples contain three types of components, polyisocyanate, polycarbonate diol, and hydroxyalkyl (meth) acrylate, as constituent units. Since these structural units are formed in the urethane (meth) acrylate oligomer while the molecular weight of each component is maintained, in this example and the comparative example, the structural component of the urethane (meth) acrylate oligomer Urethane (meth) acrylate depending on the ratio of the total amount of urethane bonds (the product of the total number of moles of polyisocyanate and the molecular weight of urethane bonds (59)) in the total amount (sum of the product of the molar ratio of each component and the molecular weight of each component) The urethane bond amount of the system oligomer was calculated.

<Mechanical properties of cured film>
(Film forming method I)
An active energy ray-curable resin composition is coated on a polyethylene terephthalate film with a bar coater to form a coating film, and then dried at 60 ° C. for 1 minute, using an electron beam irradiation device (CB175, manufactured by iGraphic). Then, after irradiating the dried coating film with an electron beam under the conditions of an acceleration voltage of 165 kV and an irradiation dose of 5 Mrad, and further curing at 23 ° C. for one day to form a cured film, the cured film is peeled off from the polyethylene terephthalate film. A cured film of about 20 μm was obtained.

(Mechanical properties of cured film)
The cured film obtained by the above-mentioned film forming method I was cut into a width of 10 mm, and using a Tensilon tensile tester (“RTC-1210A” manufactured by ORIENTEC), the temperature was 23 ° C., the relative humidity was 55% RH, and the tensile speed was 50 mm / The tensile test was performed under the conditions of the distance between the chucks of 50 mm and the breaking elongation, breaking strength, and tensile modulus. For the tensile modulus, the straight line (tangent line at the origin of the SS curve) connecting the stress at 0% elongation and the stress at 0.5% elongation of the obtained stress-strain curve (SS curve) is extended to 100%. The stress converted at the time of elongation was taken as the tensile elastic modulus.

<Other evaluation of cured film>
(Film formation method II)
The active energy ray-curable resin composition was coated on a polyethylene terephthalate film with a bar coater to form a coating film, and then dried at 60 ° C. for 1 minute. Using a high-pressure mercury lamp, the wavelength was 254 nm and the irradiation intensity was 1.0 J. The film was irradiated with ultraviolet rays under the conditions of / cm ² and further cured at 23 ° C. for 1 day to obtain a cured film having a thickness of about 10 μm laminated on polyethylene terephthalate.

<Scratch repairability: brass brush wear resistance>
In an atmosphere of 23 ° C. and 55% RH, the cured film surface laminated on the polyethylene terephthalate by the above-described film forming method II was strongly rubbed 30 times with Aswan Co., Ltd. brass brush standard type 4 rows (B-3014). Whether or not the entered wound disappeared and the time for the wound to disappear were measured and evaluated according to the following criteria.
○: No scratch ○ ⁻ : Scratch recovers in 5 minutes Δ: Scratch recovers in 30 minutes Δ ⁻ : Scratch recovers in 2 hours ×: Scratch does not recover

<Abrasion resistance: steel wool wear resistance>
And H ₁ a haze value measured before steel wool abrasion test for the above casting method II with polyethylene terephthalate on the laminated a cured film. On the other hand, under an atmosphere of 23 ° C. and 55% RH, a weight of 1000 gf (per area of 4 cm ² ) was placed on steel wool (# 0000) manufactured by Nippon Steel Wool Co., Ltd., and laminated on polyethylene terephthalate by the above film forming method II. The cured film surface laminated on polyethylene terephthalate was rubbed back and forth 15 times, and the haze value measured immediately after that was H ₂ .

Difference between H ₂ and H ₁ : ΔH (ΔH = H ₂ −H ₁ ) was determined.
In addition, in the above, the haze value was measured based on JIS K7105 using a haze meter (“HAZE METER HM-65W” manufactured by Murakami Color Research Laboratory Co., Ltd.). In addition, transparency is so high that haze value is small.
The above evaluation was performed without adding a slip agent to the active energy ray-curable resin composition (no slip agent), and the active energy ray-curable resin composition was made with a slip agent (“Silaplane” manufactured by JNC). FM-7711 ") was added using 1% by mass (in terms of solid content) (with slip agent), and using a cured film laminated on polyethylene terephthalate obtained using each composition. .

<Contamination resistance>
After 0.03 g of a 10% by mass HCl aqueous solution or 10% by mass NaOH aqueous solution (hereinafter collectively referred to as contaminants) was dropped into contact with the cured film and allowed to stand at room temperature (23 ° C.) for 24 hours. The degree of contamination after wiping off contaminants with absorbent cotton containing water was evaluated visually. The evaluation criteria are as follows.
○: Contaminant can be completely wiped out △: Contaminant remains slightly ×: Contaminant remains remarkably

<Heat resistance>
The cured film laminated on a polyethylene terephthalate by the above film forming method II, be to the spectrophotometer prior to the heat resistance test b values measured (manufactured by Minolta "SPECTROPHOTOMETER CM-3500d") and _{b 1.} On the other hand, the cured film laminated on polyethylene terephthalate by the film forming method II was put in an oven at 140 ° C., heated to 200 ° C. at a temperature rising rate of 10 ° C./min, and left for 20 minutes. After cooling to 140 ° C. at a cooling rate of 5 ° C. / min, the b value measured in the same manner after removal from the oven was b _2. The lower the b value, the better.
Difference between b ₂ and b ₁ : Δb (Δb = b ₂ −b ₁ ) was determined and evaluated according to the following criteria.
○: 0 <Δb ≦ 1
Δ: 1 <Δb ≦ 3
×: 3 <Δb

<Blocking resistance>
About the cured film laminated on polyethylene terephthalate by the above-mentioned film forming method II, the back surface of the polyethylene terephthalate film is superposed on the surface of the coating film, and a load of 150 g / cm ² is applied by a weight for 1 hour. The coating film of the composition and the back surface of the polyethylene terephthalate film were blocked. After unloading, the appearance after peeling off the blocking site by hand was visually evaluated. The evaluation criteria are as follows.
○: No trace left Δ: Trace is observed immediately after peeling, but disappears within 5 minutes ×: Trace is observed after 5 minutes after peeling

[Raw materials]
<(A-1) Polyisocyanate>
IPDI: Isophorone diisocyanate “VESTANAT IPDI” manufactured by Evonik Degussa Japan
<(A-2) High molecular weight polycarbonate polyol>
T4691: Polycarbonate polyol "Duranol T4691" manufactured by Asahi Kasei Corporation
1,4-butanediol / 1,6-hexanediol = 9/1 (mass ratio)
Number average molecular weight = 1000
Hydroxyl value: 119.4 mg-KOH / g
T4671: Polycarbonate polyol “Duranol T4671” manufactured by Asahi Kasei Corporation
1,4-butanediol / 1,6-hexanediol = 7/3 (mass ratio)
Number average molecular weight = 1000
Hydroxyl value: 111.3 mg-KOH / g
T6001: Asahi Kasei's polycarbonate polyol "Duranol T6001"
1,6-hexanediol alone
Number average molecular weight = 1000
Hydroxyl value: 115.3 mg-KOH / g
C-1090: Kuraray Polycarbonate Polyol
"Kuraray polyol C-1090"
3-methylpentanediol / 1,6-hexanediol = 9/1 (mass ratio)
Number average molecular weight = 1000
Hydroxyl value: 115.2 mg-KOH / g

<(A-3) Hydroxyalkyl (meth) acrylate>
HEA: Osaka Organic Industry Co., Ltd. 2-hydroxyethyl acrylate V300: Osaka Organic Industry Co., Ltd. pentaerythritol triacrylate “Biscoat V-300”

<(A-4) Low molecular weight polyol>
1,4-BD: 1,4-butanediol manufactured by Mitsubishi Chemical Corporation 1,12-DD: 1,12-dodecanediol manufactured by Ube Industries, Ltd. CHDM: 1,4-cyclohexanedimethanol manufactured by Shin Nippon Rika Co., Ltd.

<(A-5) Other high molecular weight polyol>
PCL210: Polycaprocraton polyol “Placcel 210” manufactured by Daicel Chemical Industries, Ltd.
Number average molecular weight: 1000
Hydroxyl value: 114.2 mg-KOH / g
PTMG1000: polyether polyol "PTMG1000" manufactured by Mitsubishi Chemical Corporation
Number average molecular weight: 1000

[Example 1]
In a four-necked flask equipped with a stirrer, reflux condenser, dropping funnel, and thermometer, 116 g of IPDI as polyisocyanate, 240 g of T4691 as high molecular weight polycarbonate polyol, and 1,4-BD as low molecular weight polyol 17 g was added, and 558 g of methyl ethyl ketone and 0.02 g of dioctyltin dilaurate were added and reacted for 9 hours while heating to 80 ° C. in an oil bath. After cooling to 60 ° C. after completion of the reaction, 0.1 g of dioctyltin dilaurate, 0.2 g of methyl hydroquinone and 41 g of methyl ethyl ketone were added, and 28 g of HEA was added dropwise as a hydroxyalkyl (meth) acrylate to initiate the reaction. The reaction is carried out for 10 hours while heating to 70 ° C. in an oil bath, the progress of the reaction is confirmed by a decrease in the peak derived from the isocyanate (NCO) group in the infrared absorption spectrum, and the end point of the reaction is confirmed by disappearance. The urethane (meth) acrylate oligomer 1 was obtained. The solution of the urethane (meth) acrylate oligomer 1 thus obtained is referred to as an active energy ray-curable resin composition 1.

The composition ratio of the raw material compounds used for the production of this urethane (meth) acrylate oligomer 1 is high molecular weight polycarbonate diol / isophorone diisocyanate / 2-hydroxyethyl acrylate = 2.1 / 4.8 / 2.2 (molar ratio). Yes, the content of the resin component (solid content) in the reaction solution is 40% by mass.
The molecular weight between calculated network crosslinking points of the obtained active energy ray-curable resin composition 1 was 4300. Moreover, the number average molecular weight of the urethane (meth) acrylate oligomer 1 calculated | required by GPC was 4300, and the urethane bond amount was 10 mass%. Other analysis results were as shown in Table 1. Furthermore, content of the urethane (meth) acrylate oligomer 1 in the active energy ray-curable resin composition 1 was 40% by mass.
The obtained active energy ray-curable resin composition 1 was evaluated as described above, and the results are shown in Table 1.

[Examples and Comparative Examples]
The urethane (meth) acrylate oligomer and activity were the same as in Example 1, except that the raw material compound and the amount used were changed to urethane (meth) acrylate oligomer raw materials having the molar ratios shown in Table 1. An energy ray-curable resin composition was produced, evaluated in the same manner, and the results are shown in Table 1.

  In the examples and comparative examples, the actually measured film thicknesses of the cured films actually measured by the above-described film forming methods I and II were as shown in Table 2 below.

  From the above results, the cured film of the active energy ray-curable resin composition of the present invention has flexibility, rupture elongation, excellent mechanical strength, scratch repairability, resistance to deformation during three-dimensional processing. It can be seen that it has both scratch resistance, heat resistance, contamination resistance, and blocking resistance at the same time.

Claims (10)

Active energy ray curable containing at least urethane (meth) acrylate oligomer (A) which is a reaction product of (a-1) polyisocyanate, (a-2) polycarbonate polyol, and (a-3) hydroxyalkyl (meth) acrylate. It is a resin composition, The diol structural unit of said (a-2) polycarbonate polyol contains 1, 4- butanediol, The tensile elasticity modulus in 23 degreeC of the cured film irradiated and irradiated with active energy is 100. An active energy ray-curable resin composition, which is ˜1000 MPa.   The active energy ray-curable resin composition according to claim 1, wherein the molecular weight between calculated crosslinking points in the composition is 1000 to 15000.   The active energy ray-curable resin composition according to claim 1 or 2, wherein the (a-1) polyisocyanate is a polyisocyanate having an alicyclic structure having 5 to 15 carbon atoms. The diol structural unit of the (a-2) polycarbonate polyol contains a 1,6-hexanediol structural unit, and the ratio of 1,4-butanediol and 1,6-hexanediol in the diol structural unit is 1 , 4-butanediol / 1,6-hexanediol = 7 /
The active energy ray-curable resin composition according to any one of claims 1 to 3, which is 3 to 10/0 (mass ratio).   The (a-3) hydroxyalkyl (meth) acrylate is a hydroxyalkyl (meth) acrylate having a C2-C4 alkylene group between a (meth) acryloyl group and a hydroxyl group. The active energy ray-curable resin composition according to claim 1.   The (a-3) hydroxyalkyl (meth) acrylate is 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, cyclohexane Dimethanol mono (meth) acrylate, addition reaction product of 2-hydroxyethyl (meth) acrylate and caprolactone, addition reaction product of 4-hydroxybutyl (meth) acrylate and caprolactone, glycidyl ether and (meth) acrylic acid An addition reaction product, a mono (meth) acrylate of glycol, pentaerythritol tri (meth) acrylate, and at least one compound selected from the group consisting of dipentaerythritol penta (meth) acrylate, The active energy ray curable resin composition according to Motomeko 1-5. The active energy ray-curable resin composition for a topcoat layer for a decorative film according to any one of claims 1 to 6. A cured film obtained by irradiating the active energy ray-curable resin composition according to any one of claims 1 to 7 with an active energy ray.   The laminated body which has a layer which consists of a cured film of Claim 8 on a base material.   The decorative film which has a layer which consists of a cured film of Claim 8 on a base material as a topcoat layer.