TW201920525A - Curable composition for extensible and scratch-resistant coating - Google Patents

Abstract

To provide a material for forming a hard coating layer having extensibility and excellent scratch resistance and presenting a transparent appearance. A curable composition containing (a) 100 mass parts of an active energy ray-curable lactone-modified polyfunctional monomer, (b) 0.1-10 mass parts of a perfluoropolyether having an active energy ray-curable group at both ends of a molecular chain containing a poly(oxyperfluoroalkylene) group via urethane bonds (however, excluding perfluoropolyether having a poly(oxyalkylene) group between the poly(oxyperfluoroalkylene) group and the urethane bond), and (c) 1-20 mass parts of a polymerization initiator that generates radicals by active energy rays, and a hard coating film provided with a hard coating layer formed from the composition.

Description

Extensible scratch-resistant hardening composition for coating

The present invention relates to a curable composition that is useful as a material for forming a hard coating layer applied to the surface of various display elements such as a touch panel display and a liquid crystal display. In detail, it is a hardenable composition that has elongation and excellent scratch resistance and can form a hard coating layer having a transparent appearance.

A large number of resin molded products are used in mobile information terminals such as mobile phones and tablet computers, notebook computers, home appliances, and automotive interior and exterior parts. In order to improve the designability of these resin-molded articles, decoration is usually performed on the surface by printing after the resin is molded. In recent years, as a method for decorating the three-dimensional surface of the above-mentioned resin molded product, a hard coating layer is used on one side of the film, and a decorative film provided with a printing layer or an adhesive layer on the other side is used to adhere these decorative films through The method of laminating and bonding to a resin molded article is being examined.

As a required characteristic of the above-mentioned decorative film, the first formability is necessary. In other words, even if it is stretched, cracks or the like cannot occur in the hard coating layer, and it is necessary to follow the stretchability of the three-dimensional surface. Second, its abrasion resistance is necessary. The hard coating layer of the decorative film is positioned on the outermost surface in a state of being bonded to the resin molded product, and plays a role of protecting the surface.

In general, when abrasion resistance is imparted to a hard coating layer, for example, by forming a highly crosslinked structure, that is, by forming a crosslinked structure with low molecular mobility, the surface hardness can be increased, and a method of imparting resistance to external forces is adopted. As these hard coating layer forming materials, a polyfunctional acrylate-based material which undergoes three-dimensional crosslinking by radicals is currently most widely used. However, polyfunctional acrylate-based materials have no extensibility at all because of their high cross-link density.
On the other hand, for imparting elongation to the hard coating layer, for example, a polyfunctional acrylate oligomer or polyfunctional urethane acrylate based on the use of a polyfunctional acrylate oligomer having a molecular weight of about 1,000 to 10,000 is adjusted. Oligo method. These multifunctional acrylate-based oligomers have a cross-linking site and an extension site in the molecular structure, and can exhibit moderate extensibility due to the molecular mobility of the extension site. However, the cross-linking density will reduce its abrasion resistance.
In this way, there is a trade-off relationship between the elongation of the hard coating layer and the abrasion resistance, and it has been a problem to combine both characteristics.

However, for a portable information terminal represented by a mobile phone, a person can grasp it with his hand and perform a touch operation with his finger. Therefore, when the hand is held, fingerprints are attached to the casing, which may cause problems that impair the appearance. The fingerprint contains moisture derived from sweat and oil derived from sebum. If these are not to be easily adhered, it is highly anticipated that the hard coating layer on the surface of the casing provides water repellency and oil repellency.
From such a viewpoint, it is known that antifouling properties such as fingerprints are expected on the surface of the housing of a portable information terminal. However, even if the initial antifouling performance can reach a fairly high level, since people must touch it every day, their functions are often reduced during use. Therefore, durability of antifouling properties during use becomes a problem.

Conventionally, as a method for imparting antifouling properties to the surface of a hard coating layer, a method of adding a small amount of a fluorine-based surface modifier to a coating liquid for forming a hard coating layer has been used. The fluorine-based compound to be added is segregated on the surface of the hard coating layer by the low surface energy to impart water repellency and oil repellency. As a fluorine-based compound, from the viewpoint of water repellency and oil repellency, an oligomer having a number average molecular weight of about 1,000 to 5,000, which is a perfluoropolyether having a poly (oxyperfluoroalkylene) chain, is used . However, perfluoropolyethers are generally difficult to dissolve in organic solvents used in the coating liquid used to form the hard coating layer because of their preferred fluorine concentration. In addition, the formed hard coating layer also causes an agglomeration phenomenon.
In such a perfluoropolyether, in order to impart solubility to an organic solvent and dispersibility to a hard coating layer, it is used as a method for adding an organic site to a perfluoropolyether. In order to impart abrasion resistance, an active energy ray hardening site represented by a (meth) acrylate group is used.
Hitherto, as an antifouling hard coating layer having scratch resistance, a component that imparts antifouling properties to the surface of the hard coating layer has been disclosed at both ends of the poly (oxyperfluoroalkylene) chain and will have A technique for using a poly (oxyalkylene) group and a (meth) acrylfluorenyl compound with a urethane bond as a surface modifier (Patent Document 1).
[Prior technical literature]
[Patent Literature]

[Patent Document 1] International Publication No. 2016/163479

[Problems Solved by the Invention]

However, for the purpose of imparting scratch resistance to a hard coating layer exhibiting elongation, the surface modifier of Patent Document 1 is added to polyfunctional acrylate oligomers, etc., because of their high molecular weight and hydrophobicity. The compatibility of the hardened layer of the hardened material is deteriorated due to its poor compatibility.

[Means for solving problems]

The present inventors conducted repeated detailed review results to achieve the above-mentioned purpose, and found that the poly (oxyperfluoroalkylene) group-containing molecular chain has no poly (oxyalkylene) group at both ends. In addition, a perfluoropolyether having an active energy ray polymerizable group across a urethane bond has solubility in a coating solution for forming a hard coating layer containing a lactone-denatured polyfunctional monomer, and hard coating. A hardening composition with excellent dispersibility in the layer and containing the perfluoropolyether and lactone-denatured polyfunctional monomer, which has elongation and excellent scratch resistance, and can form a hard coating layer exhibiting a transparent appearance. invention.

That is, the first aspect of the present invention relates to a curable composition containing
(a) 100 parts by mass of an active energy ray-curable lactone-denatured polyfunctional monomer,
(b) a perfluoropolyether having an active energy ray polymerizable group via a urethane bond at both ends of a molecular chain containing a poly (oxyperfluoroalkylene) group (except 0.1 to 10 parts by mass of a perfluoropolyether having a poly (oxyalkylene) group between the (oxyperfluoroalkylene) group and the aforementioned urethane bond), and (c) active energy 1 to 20 parts by mass of a polymerization initiator for generating radicals.
As a second viewpoint, the (b) perfluoropolyether-based curable composition described in the first viewpoint has at least two active energy ray polymerizable groups on each of both ends.
As a third aspect, the (b) perfluoropolyether-based curable composition described in the second aspect has at least three active energy ray polymerizable groups on each of both ends.
As a fourth aspect, the poly (oxyperfluoroalkylene) group is any one of the first to third aspects having a group having-[OCF ₂ ]-and-[OCF ₂ CF ₂ ]-as repeating units. The curable composition according to one item.
As a fifth aspect, the (b) perfluoropolyether-based curable composition described in the fourth aspect has a partial structure represented by formula [1].

(In the formula, n is the sum of the number of repeating units-[OCF ₂ CF ₂ ]-and the number of repeating units-[OCF ₂ ]-, which is an integer from 5 to 30.)
In a sixth aspect, the (a) polyfunctional monosystem contains a compound selected from a lactone-denatured polyfunctional (meth) acrylate compound and a lactone-denatured polyfunctional urethane (meth) acrylate compound. The curable composition according to any one of the first to fifth aspects of at least one group.
As a seventh aspect, the (a) polyfunctional monomer is an ε-caprolactone-denatured polyfunctional monomer, and is a curable composition according to any one of the first to sixth aspects.
The eighth aspect is the curable composition according to any one of the first to seventh aspects that further contains (d) a solvent.
The ninth aspect relates to a cured film obtained by the curable composition according to any one of the first to eighth aspects.
The tenth aspect is a hard coating film including a hard coating layer on at least one surface of a film substrate, and the hard coating layer is a hard coating film made of the cured film according to the ninth aspect.
The eleventh aspect is a hard coating film having a hard coating layer on at least one side of a film substrate, and the hard coating layer is described by including any one of the first to eighth aspects. A hard coating film formed by a step of applying a curable composition on a film substrate to form a coating film, and a step of irradiating the coating film with active energy rays to harden it.
The twelfth aspect is the hard coating film according to the tenth aspect or the eleventh aspect, in which the hard coating layer has a film thickness of 1 to 10 μm.
As a thirteenth aspect, it relates to a poly (oxyperfluoroalkylene) -containing molecular chain having at least three active energy ray polymerizable groups at each of both ends through a urethane bond. Perfluoropolyether compounds (except for perfluoropolyether compounds having a poly (oxyalkylene) group between the poly (oxyperfluoroalkylene) group and the urethane bond).
As a fourteenth aspect, the perfluoropolyene described in the thirteenth aspect is that the poly (oxyperfluoroalkylene) group has-[OCF ₂ ]-and-[OCF ₂ CF ₂ ]-as repeating units. Ether compounds.
A fifteenth aspect is the perfluoropolyether compound described in the fourteenth aspect with a partial structure represented by formula [1].

(In the formula, n is the total of the number of repeating units-[OCF ₂ CF ₂ ]-and the number of repeating units-[OCF ₂ ]-, which represents an integer of 5 to 30).
A sixteenth aspect relates to a surface modifier made of the perfluoropolyether compound described in any one of the thirteenth to fifteenth aspects.
A seventeenth aspect relates to the use of the perfluoropolyether compound described in any one of the thirteenth to fifteenth aspects for surface modification.

[Effect of the invention]

According to the present invention, it is possible to provide a hardenable composition having excellent scratch resistance and excellent appearance on a thin film having a thickness of about 1 to 10 μm, and having extensibility, which is used for forming a cured film and a hard coating layer.
In addition, according to the present invention, there can be provided a hardened film obtained from the hardenable composition or a hard coating film provided on the surface by the hard coating layer formed therefrom, which has scratch resistance and excellent appearance, and has extensibility. Hard coating film.

＜ Sclerosing composition ＞
The curable composition of the present invention contains the following (a) to (c) in detail.
(a) 100 parts by mass of an active energy ray-curable lactone-denatured polyfunctional monomer,
(b) a perfluoropolyether having an active energy ray polymerizable group via a urethane bond at both ends of a molecular chain containing a poly (oxyperfluoroalkylene) group (except (Except perfluoropolyether having a poly (oxyalkylene) group between the (oxyperfluoroalkylene) group and the urethane bond) 0.1 to 10 parts by mass), and
(c) 1 to 20 parts by mass of a polymerization initiator that generates radicals through active energy rays.
Hereinafter, each of the components (a) to (c) will be described first.

[(a) Active energy ray-curable lactone-denatured polyfunctional monomer]
The so-called active energy ray-curable lactone-denatured polyfunctional monosystem refers to a polyfunctional monomer that is denatured with lactone, which undergoes a polymerization reaction by irradiating an active energy ray such as ultraviolet rays and hardens it.
Preferred (a) active energy ray-curable lactone-denatured polyfunctional monomers for the curable composition of the present invention are selected from lactone-denatured polyfunctional (meth) acrylate compounds and lactone-denatured polyfunctional amine groups. Monomers of formate (meth) acrylate compounds.
In addition, the (meth) acrylate compound of this invention means both an acrylate compound and a methacrylate compound. For example, (meth) acrylic acid means acrylic acid and methacrylic acid.

Examples of the lactone-denatured polyfunctional (meth) acrylate compound include denaturation with lactones such as γ-butyrolactone, δ-valerolactone, and ε-caprolactone. Cycloaddition or ring-opening addition polymerization) (meth) acrylate compounds of polyols or polythiols.
Examples of the polyhydric alcohol include trimethylolpropane, ditrimethylolpropane, pentaerythritol, dipentaerythritol, glycerol, bisphenol A, ethoxylated trimethylolpropane, ethoxylated pentaerythritol, and ethyl acetate. Oxidized dipentaerythritol, ethoxylated glycerol, ethoxylated bisphenol A, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,6-hexanedidiol Alcohol, 2-methyl-1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, tricyclo [5.2.1.0 ^2,6 ] decanedimethanol, 1, 3-adamantanediol, 1,3-adamantanedimethanol, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, neopentyl Diol, dioxane glycol, bis (2-hydroxyethyl) isocyanurate, ginseng (2-hydroxyethyl) isocyanurate, 9,9-bis (4-hydroxyphenyl) 芴, 9,9-bis [4- (2-hydroxyethoxy) phenyl] fluorene and the like.
Examples of the thiol include bis (2-mercaptoethyl) sulfide and bis (4-mercaptophenyl) sulfide.

Examples of such lactone-modified polyfunctional (meth) acrylate compounds include lactone-modified trimethylolpropane tri (meth) acrylate and lactone-modified bistrimethylolpropane tetra (meth) acrylic acid. Ester, lactone-modified pentaerythritol di (meth) acrylate, lactone-modified pentaerythritol tri (meth) acrylate, lactone-modified pentaerythritol tetra (meth) acrylate, lactone-modified dipentaerythritol penta (meth) acrylate Lactone denatured dipentaerythritol hexa (meth) acrylate, lactone denatured 2-hydroxy-1,3-bis (meth) propenyloxypropane, lactone denatured 2-hydroxy-1-propenyloxy- 3-methacrylic acid oxypropane, lactone modified glycerol tri (meth) acrylate, lactone modified bisphenol A di (meth) acrylate, lactone modified ethoxylated trimethylolpropane tri (methyl) Acrylate), lactone modified ethoxylated pentaerythritol tetra (meth) acrylate, lactone modified ethoxylated dipentaerythritol hexa (meth) acrylate, lactone modified ethoxylated glycerol tri (methyl) ) Acrylate, lactone denatured ethoxylated bisphenol A di (meth) acrylate, lactone denatured 1,3-propane Alcohol di (meth) acrylate, lactone denaturation 1,3-butanediol di (meth) acrylate, lactone denaturation 1,4-butanediol di (meth) acrylate, lactone denaturation 1, 6-Hexanediol di (meth) acrylate, lactone denatured 2-methyl-1,8-octanediol di (meth) acrylate, lactone denatured 1,9-nonanediol bis (methyl) Acrylate), lactone denatured 1,10-decanediol di (meth) acrylate, lactone modified tricyclic [5.2.1.0 ^2,6 ] decane dimethanol di (meth) acrylate, internal Ester denatured 1,3-adamantanediol di (meth) acrylate, lactone denatured 1,3-adamantane dimethanol di (meth) acrylate, lactone denatured ethylene glycol di (meth) acrylate Lactone modified diethylene glycol di (meth) acrylate, lactone modified triethylene glycol di (meth) acrylate, lactone modified tetraethylene glycol di (meth) acrylate, lactone modified poly Ethylene glycol di (meth) acrylate, lactone modified propylene glycol di (meth) acrylate, lactone modified dipropylene glycol di (meth) acrylate, lactone modified polypropylene glycol di (meth) acrylate, internal Ester denaturation neopentyl glycol di (meth) acrylate, lactone denaturation Oxaneglycol di (meth) acrylate, lactone denatured bis (2-hydroxyethyl) isocyanurate di (meth) acrylate, lactone denatured ginseng (2-hydroxyethyl) isocyanurate Ester tris (meth) acrylate, lactone denatured 9,9-bis (4- (meth) acrylic alkoxyphenyl) fluorene, lactone denatured 9,9-bis [4- (2- (form Propyl) propenyloxyethoxy) phenyl] fluorene, lactone-modified bis [2- (meth) acrylfluorenylthioethyl] sulfide, lactone-modified bis [4- (meth) acrylic acid] Thienyl] sulfide and the like.

Among them, ε-caprolactone is preferred as the modified lactone, and for example, a compound in which the lactone of the lactone-denatured polyfunctional (meth) acrylate compound is ε-caprolactone is preferred.
Examples of preferred lactone-denatured polyfunctional (meth) acrylate compounds include ε-caprolactone-modified pentaerythritol tri (meth) acrylate, ε-caprolactone-modified pentaerythritol tetra (meth) acrylate, ε-caprolactone-denatured dipentaerythritol penta (meth) acrylate, ε-caprolactone-denatured dipentaerythritol hexa (meth) acrylate, and the like.

The lactone-denatured polyfunctional urethane (meth) acrylate compound has a plurality of (meth) acrylfluorenyl groups in one molecule, has a urethane bond (-NHCOO-), and has, for example, γ -A compound having a ring-opening structure of lactones such as butyrolactone, δ-valerolactone, and ε-caprolactone.
For example, examples of the lactone-modified polyfunctional urethane (meth) acrylate include those obtained by a reaction between a polyfunctional isocyanate and a (meth) acrylate having a hydroxy group modified with lactone. The lactone-denatured polyfunctional urethane (meth) acrylate which can be used in the present invention is obtained from a reaction of a polyfunctional isocyanate, a (meth) acrylate having a hydroxyl group, and a polyol modified with lactone, and the like. The compounds are not limited to these examples.

Examples of the polyfunctional isocyanate include toluene diisocyanate, isophorone diisocyanate, xylene diisocyanate, and hexamethylene diisocyanate.
Examples of the (meth) acrylate having a hydroxyl group include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, pentaerythritol tri (meth) acrylate, and Pentaerythritol penta (meth) acrylate, tripentaerythritol hepta (meth) acrylate, and the like.
Examples of the polyhydric alcohol include glycols such as ethylene glycol, propylene glycol, neopentyl glycol, 1,4-butanediol, 1,6-hexanediol, diethylene glycol, and dipropylene glycol; these Polyester polyols; reaction products of glycols with aliphatic dicarboxylic acids or dicarboxylic anhydrides such as succinic acid, maleic acid, and adipic acid; polyether polyols; polycarbonate diols, and the like.

In the present invention, as the (a) active energy ray-curable lactone-denatured polyfunctional monomer, the lactone-denatured polyfunctional (meth) acrylate compound and the lactone-denatured polyfunctional aminocarboxylic acid can be used. Ester (meth) acrylate compounds are grouped individually or in combination of two or more.

[(b) A perfluoropolyether having an active energy ray polymerizable group via a urethane bond at both ends of a molecular chain containing a poly (oxyperfluoroalkylene) group (except for the foregoing (Except for perfluoropolyethers having poly (oxyalkylene) groups between the poly (oxyperfluoroalkylene) group and the aforementioned urethane bond)])
In the present invention, as the component (b), it is used on both ends of the molecular chain containing a poly (oxyperfluoroalkylene) group, without a poly (oxyalkylene) group and an aminomethyl group interposed therebetween. An acid-bonded perfluoropolyether having an active energy ray polymerizable group (hereinafter referred to as "(b) a perfluoropolyether having a polymerizable group at both ends"). The component (b) functions as a surface modifier in the hard coating layer to which the curable composition of the present invention is applied.
In addition, the component (b) is excellent in compatibility with the component (a), whereby the appearance of white turbidity of the hard coating layer can be suppressed, and a hard coating layer having a transparent appearance can be formed.
The poly (oxyalkylene) group refers to a group in which the number of repeating units of the oxyalkylene group is 2 or more, and the alkylene group in the oxyalkylene group is an unsubstituted alkylene group.

The number of carbon atoms of the alkylene group in the poly (oxyperfluoroalkylene) group is not particularly limited, and one having 1 to 4 carbon atoms is preferred. That is, the above-mentioned poly (oxyperfluoroalkylene) group represents a group having a structure in which a divalent fluorocarbon group having 1 to 4 carbon atoms and an oxygen atom are mutually connected, and the oxygen perfluoroalkylene group has a carbon atom. A base having a structure in which a divalent fluorocarbon group of 1 to 4 is connected to an oxygen atom. Specific examples include-[OCF ₂ ]-(oxyperfluoromethyl),-[OCF ₂ CF ₂ ]-(oxyperfluoroethyl),-[OCF ₂ CF ₂ CF ₂ ]-(oxyperfluoro Propane-1,3-diyl),-[OCF ₂ C (CF ₃ ) F]-(oxyperfluoropropane-1,2-diyl) and the like.
The above-mentioned oxygen perfluoroalkylene may be used alone or in combination of two or more kinds, and depending on the required plural kinds of oxygen perfluoroalkylene, the bonding may be any of chimeric bonding and random bonding.

Among these, from the viewpoint of obtaining a cured film having good scratch resistance, as the poly (oxyperfluoroalkylene) group,-[OCF ₂ ]-(oxygen Both fluoromethyl) and-[OCF ₂ CF ₂ ]-(oxyperfluoroethyl) groups are preferred.
Wherein also (perfluoro alkylene oxy) group, as the repeating units in poly: - [OCF _2] - and - [OCF ₂ CF _2] - the molar ratio of [repeating unit: - [OCF _2] - ]: [Repeat unit:-[OCF ₂ CF ₂ ]-] = groups contained in a ratio of 2: 1 to 1: 2 are preferred, and groups contained in a ratio of about 1: 1 are more preferred. The bonding of these repeating units may be either a chimeric bonding or a random bonding.
Among the repeating units of the oxygen perfluoroalkylene, the total of the repeating units is preferably in the range of 5 to 30, and more preferably in the range of 7 to 21.
The weight average molecular weight (Mw) of the poly (oxyperfluoroalkylene) group measured by polystyrene conversion by gel permeation chromatography is 1,000 to 5,000, and preferably 1,500 to 2,000.

Examples of the active energy ray polymerizable group bonded through the urethane bond include a (meth) acrylfluorenyl group, a urethane (meth) acrylfluorenyl group, and a vinyl group.

(b) The perfluoropolyether having a polymerizable group at both ends is not limited to those having an active energy ray polymerizable group such as a (meth) acrylfluorenyl group at both ends, but may also have 2 at both ends. Those having more than one active energy ray polymerizable group, for example, as the terminal structure containing the active energy ray polymerizable group, may include the structures of A1 to A5 shown below, and the methacryl group in these structures is methacryl group Superseded structure.

Examples of the perfluoropolyether (b) having a polymerizable group at both ends thereof include a compound represented by the following formula [2].

(In the formula, A represents one of the structures represented by the aforementioned formulas [A1] to [A5], and the structure in which the propylene fluorenyl group is replaced with a methacryl fluorenyl group, and PFPE indicates the aforementioned poly (oxy Perfluoroalkylene group (However, the side directly bonded to L ¹ is an oxygen terminal, and the side bonded to an oxygen atom is a perfluoroalkylene terminal.), L ¹ represents a substitution with 1 to 3 fluorine atoms. For an alkylene group having 2 to 3 carbon atoms, m each independently represents an integer of 1 to 5, and L ² represents an m + 1-valent residue from which an OH is removed from an m + 1-valent alcohol).

Examples of the above-mentioned alkylene group having 2 to 3 carbon atoms which may be substituted by 1 to 3 fluorine atoms include CH ₂ CHF, CH ₂ CF ₂ , CHFCF ₂ , CH ₂ CH ₂ CHF, CH ₂ CH ₂ CF ₂ , CH ₂ CHFCF ₂ and the like, preferably CH ₂ CF ₂ .

Examples of the partial structure (A-NHC (= O) O) _m L ² -in the compound represented by the formula [2] include the structures represented by the following formulas [B1] to [B12].


(In the formula, A represents one of the structures represented by the aforementioned formulas [A1] to [A5], and a structure in which the propylene fluorenyl group is replaced by a methacryl fluorenyl group in these structures.)
Among the structures shown by the above formulas [B1] to [B12], the formulas [B1] and [B2] correspond to the case of m = 1, and the formulas [B3] to [B6] correspond to the case of m = 2 Equations [B7] to [B9] correspond to the case of m = 3, and equations [B10] to [B12] correspond to the case of m = 5.
Among them, the structure shown by formula [B3] is also preferable, and the combination of formula [B3] and formula [A3] is particularly preferable.

As a preferable (b) perfluoropolyether which has a polymerizable group at both ends, the compound which has a partial structure represented by Formula [1] is mentioned.

The partial structure represented by formula [1] corresponds to a portion where A-NHC (= O) is removed from the compound represented by formula [2].
N in formula [1] represents the total number of repeating units-[OCF ₂ CF ₂ ]-and the number of repeating units-[OCF ₂ ]-, preferably an integer ranging from 5 to 30, and 7 to 21 An integer in the range is preferred. The ratio of the number of repeating units-[OCF ₂ CF ₂ ]-to the number of repeating units-[OCF ₂ ]-is preferably in the range of 2: 1 to 1: 2, and the ratio in the range of approximately 1: 1 is more favorable. good. The bonding of these repeating units may be either a chimeric bonding or a random bonding.

The use ratio of the perfluoropolyether having a polymerizable group at both ends of the present invention (b) is 0.1 to 10 parts by mass with respect to 100 parts by mass of the active energy ray-curable lactone-denatured polyfunctional monomer (a), The ratio is preferably 0.2 to 5 parts by mass.

The above (b) perfluoropolyether having a polymerizable group at both ends can be obtained by, for example, the following formula [3]

(In the formula, PFPE, L ¹ , L ² and m have the same meanings as above.) The hydroxyl groups present on both ends of the compound represented by the compound are isocyanate compounds having a polymerizable group, that is, the aforementioned formulas [A1] to [A5] Compounds shown in the structures shown and those in which the propylene fluorenyl group is substituted with a methacryl fluorene group are bonded to isocyanate groups (e.g., 2- (meth) acryl methoxyethyl isocyanate, 1 , 1-bis ((meth) acryloxymethyl) ethyl isocyanate, etc.) are obtained by reacting to form a urethane bond.

In addition, in the hardenable composition of the present invention, except that (b) the poly (oxyperfluoroalkylene) group-containing molecular chain has active energy ray polymerization via urethane bonds at both ends of the molecular chain Perfluoropolyether (but not having a poly (oxyalkylene) group between the poly (oxyperfluoroalkylene) group and the urethane bond), A perfluoropolyether having a urethane bond at one end of a molecular chain containing a poly (oxyperfluoroalkylene) group, an active energy ray polymerizable group, and a hydroxyl group at the other end (but No poly (oxyalkylene oxide) between the aforementioned poly (oxyperfluoroalkylene) group and the aforementioned urethane bond, and between the aforementioned poly (oxyperfluoroalkylene) group and the aforementioned hydroxyl group Group), or a perfluoropolyether having a poly (oxyperfluoroalkylene) group having a hydroxyl group at both ends of the molecular chain as shown in the above formula [3] (however, in the aforementioned poly (oxy Group does not have a poly (oxyalkylene) group between the hydroxyl group and the aforementioned hydroxyl group] [a compound having no active energy ray polymerizable group].

The present invention relates to a perfluoropolyether compound having at least three active energy ray polymerizable groups via a urethane bond at each end of a molecular chain containing a poly (oxyperfluoroalkylene) group. (Except for the perfluoropolyether compound having a poly (oxyalkylene) group between the poly (oxyperfluoroalkylene) group and the urethane bond).
The perfluoropolyether compound having a polymerizable group at both ends is preferably a compound having a partial structure represented by the above formula [1].
As described above, the perfluoropolyether compound of the present invention has excellent compatibility with the component (a), thereby suppressing the appearance of white turbidity of the hard coating layer, and achieving an excellent effect of forming a hard coating layer having a transparent appearance.
The present invention also relates to a surface modifier made of the above-mentioned perfluoropolyether compound, and a person who intends to use the surface modifier of the perfluoropolyether compound.

[(c) Polymerization initiator that generates free radicals through active energy rays]
In the curable composition of the present invention, a polymerization initiator (hereinafter sometimes referred to simply as "(c) polymerization initiator") which generates radicals by active energy rays is preferred. Active energy rays such as ultraviolet rays and X-rays are particularly polymerization initiators that generate radicals by irradiation with ultraviolet rays.
Examples of the (c) polymerization initiator include benzoin, alkylacetophenone, thioxanthone, azo, azide, diazine, and o-quinone diazide. , Fluorenylphosphine oxides, oxime esters, organic peroxides, benzophenones, biscoumarins, bisimidazoles, titanocene, thiols, halogenated hydrocarbons, trichloromethyl Triazines, or onium salts such as iodine salts and sulfonium salts. One type may be used alone, or two or more types may be used in combination.
Among these, from the viewpoints of transparency, surface hardening, and film hardening, as the (c) polymerization initiator, alkylacetophenones are preferably used. By using an alkyl acetophenone, a hardened film having improved scratch resistance can be obtained.

Examples of the alkylacetophenones include 1-hydroxycyclohexyl = phenyl = ketone, 2-hydroxy-2-methyl-1-phenylpropane-1-one, and 2-hydroxy-1- ( 4- (2-hydroxyethoxy) phenyl) -2-methylpropane-1-one, 2-hydroxy-1- (4- (4- (2-hydroxy-2-methylpropanyl) benzene Α-hydroxyalkylacetophenones such as methyl) phenyl) -2-methylpropane-1-one; 2-methyl-1- (4- (methylthio) phenyl) -2-? Α-Aminoalkylacetophenones such as phosphonopropane-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) butane-1-one ; 2,2-dimethoxy-1,2-diphenylethane-1-one; methyl phenylglyoxylate and the like.

In the present invention, the use ratio of the (c) polymerization initiator is 1 to 20 parts by mass, and preferably 2 to 10 parts by mass with respect to 100 parts by mass of the aforementioned (a) active energy ray-curable lactone-denatured polyfunctional monomer. Serving.

[(d) Solvent]
The curable composition of the present invention may further contain (d) a solvent, that is, it may be in the form of a paint (film-forming material).
As the above-mentioned solvent, when dissolving the components (a) to (c), and considering the workability at the time of the coating formed by the cured film (hard coating layer) described later, the drying property before and after curing, etc., it is only appropriately selected It may be, for example, aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene, and tetralin; aliphatic or alicyclic compounds such as n-hexane, n-heptane, mineral oil, and cyclohexane Hydrocarbons; methyl chloride, methyl bromide, methyl iodide, dichloromethane, chloroform, carbon tetrachloride, trichloroethylene, perchloroethylene, o-dichlorobenzene and other halogen compounds; acetic acid Esters or ester ethers such as ethyl acetate, butyl acetate, methoxybutyl acetate, methyl cellosolve acetate, ethyl cellosolve acetate, propylene glycol monomethyl ether acetate; Diethyl ether, tetrahydrofuran, 1,4-dioxane, methyl cellosolve, ethyl cellosolve, butyl cellosolve, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono-n-propyl Ethers such as ether, propylene glycol monoisopropyl ether, propylene glycol mono-n-butyl ether; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, di-n-butyl ketone, cyclohexanone ; Alcohols, ethanol, n-propanol, isopropanol, n-butanol, isobutyl alcohol, tert-butyl alcohol, 2-ethylhexyl alcohol, benzyl alcohol, ethylene glycol and other alcohols; N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, and other amines; dimethyl fluorene and other fluorenes; and two or more of these Mixed solvents.
The use amount of these (d) solvents is not particularly limited. For example, the solid content concentration in the curable composition of the present invention is preferably 1 to 70% by mass, and preferably used at a concentration of 5 to 50% by mass. The so-called solid content concentration (also referred to as the non-volatile content concentration) means the total mass (total mass) of the aforementioned (a) to (d) components (and other additives depending on the desire) of the curable composition of the present invention. The content of solid components (those that remove solvent components from all components).

[Other additives]
In addition, the curable composition of the present invention may be appropriately added with general additives as necessary without impairing the effects of the present invention. For example, polymerization inhibitors, photosensitizers, leveling agents, and interfacial activities may be appropriately added. Agents, adhesion-imparting agents, plasticizers, ultraviolet absorbers, antioxidants, storage stabilizers, antistatic agents, inorganic fillers, pigments, dyes, and the like.

<Hardened film>
The curable composition of the present invention is coated on a substrate to form a coating film, and the coating film is irradiated with active energy rays to polymerize (harden) the cured film to form a cured film. This cured film is also an object of the present invention. Moreover, the hard coating layer in the hard coating film mentioned later can be made into the said hardened film.
Examples of the substrate in this case include various resins (polycarbonate, polymethacrylate, polystyrene, polyethylene terephthalate (PET), or polyethylene naphthalate.) (PEN) and other polyesters, polyolefins, polyamides, polyimides, epoxy resins, melamine resins, triethyl cellulose, acrylonitrile-butadiene-styrene copolymer (ABS), acrylonitrile- Styrene copolymer (AS), norbornene resin, etc.), metal, wood, paper, glass, slate, etc. The shape of these substrates may be a plate shape, a film shape, or a three-dimensional molded body.

For the coating method on the substrate, a cast coating method, a spin coating method, a doctor blade coating method, a dip coating method, a roll coating method, a spray coating method, a bar coating method, a die coating method, an inkjet method, and printing can be appropriately selected. Method (letter, gravure, lithography, screen printing, etc.), among which a roll-to-roll method can be used, and from the viewpoint of film coating property, it is expected to use a letterpress printing method, and especially a gravure Coating method. In addition, a filter having a pore size of about 0.2 μm or the like is used in advance, and the curable composition is filtered, and then it is preferably provided to a coater. In addition, when coating, if necessary, a solvent may be added to the curable composition as a form of painting. Examples of the solvent in this case include various solvents listed in the above [(d) Solvent].
After applying a curable composition to a base material to form a coating film, if necessary, the coating film is pre-dried by a hot plate or an oven to remove the solvent (solvent removal step). As a condition of heat drying at this time, for example, it is preferable to carry out at 40 to 120 ° C. for about 30 seconds to 10 minutes.
After drying, the coating is cured by irradiating active energy rays such as ultraviolet rays. Examples of the active energy rays include ultraviolet rays, electron rays, and X-rays, and ultraviolet rays are particularly preferred. As a light source used for ultraviolet irradiation, solar rays, chemical lamps, low-pressure mercury lamps, high-pressure mercury lamps, metal halide lamps, xenon lamps, UV-LEDs, and the like can be used.
After that, the polymerization is completed by performing post-baking, specifically heating using a hot plate, an oven, or the like.
The thickness of the formed cured film is usually 0.01 to 50 μm, preferably 0.05 to 20 μm after drying and curing.

＜ Hard Coating Film ＞
By using the curable composition of the present invention, a hard coating film having a hard coating layer on at least one side (surface) of a film substrate can be produced. The hard coating film is also an object of the present invention, and the hard coating film is suitable for protecting the surface of various display elements such as a touch panel or a liquid crystal display.

The hard coating layer in the hard coating film of the present invention may include the step of coating the hardening composition of the present invention on a film substrate to form a coating film, and irradiating the coating film with active energy rays such as ultraviolet rays to make the coating. It is formed by the method of the step of film hardening.

Examples of the film substrate include various transparent resin films which can be used for optical applications among the substrates listed in the aforementioned <cured film>. Preferred examples include polymers selected from polyethylene terephthalate (PET), polybutylene terephthalate (PBT), and polyethylene naphthalate (PEN). Resin films such as ester, polycarbonate, polymethacrylate, polystyrene, polyolefin, polyamide, polyimide, and triethyl cellulose.
In addition, the coating method (coating film formation step) and the active energy ray irradiation method (hardening step) of the hardening composition on the film substrate may be the methods listed in the aforementioned <cured film>. When the curable composition of the present invention contains a solvent (in the form of a paint), after the coating film forming step, a step of drying the coating film to remove the solvent may be included as necessary. In this case, the drying method (solvent removal step) of the coating film mentioned in the said <hardened film> can be used.
The film thickness of the hard coating layer thus obtained is preferably 1 to 20 μm, and more preferably 1 to 10 μm.

[Example]

Examples will be given below to explain the present invention more specifically, but the present invention is not limited to the following examples.
In the examples, the devices and conditions used for the preparation of the samples and the analysis of the physical properties are as follows.

(1) Bar coating device: (share) PM-9050MC made by SMT
Bar: A-Bar OSP-22, manufactured by OSG System Products, with a maximum wet film thickness of 22 μm (equivalent to wire ingot # 9)
Coating speed: 4m / min
(2) Oven device: DRC433FA dust-free dryer made by Advantech Oriental
(3) UV curing device: CV-110QC-G made by Heraeus
Light: High-pressure mercury lamp H-bulb made by Heraeus
(4) Gel permeation chromatography (GPC)
Installation: HLC-8220GPC made by Tosoh Corporation
Column: Shodex (registered trademark) GPC K-804L, GPC K-805L, manufactured by Showa Denko Corporation
Column temperature: 40 ℃
Eluent: Tetrahydrofuran Detector: RI
(5) Scratch test device: New East Scientific Co., Ltd. Tribogear Type: 30S
Scanning speed: 3,000mm / minute Scanning distance: 50mm
(6) Full light transmittance and haze device: HND tester NDH5000 made by Nippon Denshoku Industries Co., Ltd.
(7) Contact angle device: DropMaster DM-501 made by Kyowa Interface Science Co., Ltd.
Measurement temperature: 20 ℃
(8) Tensile test device: Autograph AGS-10 kNX made by Shimadzu Corporation
Gripper: 1kN manual torsion type flat gripper Gripper: High-strength coated gripper Stretching speed: 20mm / min Measuring temperature: 20 ℃

The abbreviated number indicates the following meaning.
PFPE1: Perfluoropolyether having two hydroxyl groups at both ends without a poly (oxyalkylene) group interposed [Fomblin (registered trademark) T4 manufactured by Solvay Specialty Polymers, Inc.]
PFPE2: Perfluoropolyether having a hydroxyl group with a poly (oxyalkylene) group (repeating unit number 8-9) at both ends [Fluorolink 5147X manufactured by Solvay Specialty Polymers, Inc.]
SM2: Perfluoropolyether having two methacrylfluorene groups at each end via a urethane bond [Fomblin (registered trademark) MT70 manufactured by Solvay Specialty Polymers, Inc., 80% by mass MEK solution]
BEI: 1,1-bis (propenyloxymethyl) ethyl isocyanate [Karenz (registered trademark) manufactured by Showa Denko Corporation]
DOTDD: Dioctyltin dineodecanoate [Neostan (registered trademark) U-830 made by Nitto Kasei Co., Ltd.]
DPCL: Caprolactone denatured dipentaerythritol hexaacrylate [KAYARAD DPCA-60, manufactured by Nippon Kayaku Co., Ltd.]
DPHA: Dipentaerythritol pentaacrylate / dipentaerythritol hexaacrylate mixture [KAYARAD DPHA manufactured by Nippon Kayaku Co., Ltd.]
PETA: Pentaerythritol triacrylate / Pentaerythritol tetraacrylate mixture [NK ester A-TMM-3LM-N made by Shin Nakamura Chemical Industry Co., Ltd.]
I2959: 2-hydroxy-1- (4- (2-hydroxyethoxy) phenyl) -2-methylpropane-1-one [BASF Japan (Stock) IRGACURE (registered trademark) 2959]
MEK: methyl ethyl ketone
PGME: propylene glycol monomethyl ether

[Example 1] Manufacture of perfluoropolyether (SM1) having 4 acryl fluorenyl groups through urethane bonds at each of the two ends, 1.19 g (0.5 mmol) of PFPE1 and 0.52 g of BEI were charged into a screw tube ( 2.0 mmol), DOTDD 0.017 g (0.01 times the total mass of PFPE1 and BEI), and MEK 1.67 g. This mixture was stirred at room temperature (about 23 ° C.) for 24 hours using a stirrer tablet to obtain a 50% by mass MEK solution of the target compound SM1.
The weight average molecular weight measured by GPC of the obtained SM1 in terms of polystyrene: Mw was 3,000, and the degree of dispersion: Mw (weight average molecular weight) / Mn (number average molecular weight) was 1.2.

[Manufacturing Example 1] Preparation of a 50% by mass MEK solution of SM2 In a screw tube, 2.5 g of SM2 and 1.5 g of MEK were charged. This mixture was stirred at room temperature (about 23 ° C.) for 24 hours using a stirrer tablet to obtain a 50% by mass MEK solution of SM2.

[Comparative Manufacturing Example 1] Perfluoropolyether (SM3) having two acryl groups at both ends with a poly (oxyalkylene) group and one urethane bond interposed therebetween was manufactured in a screw tube 1.05 g (0.5 mmol) of PFPE2, 0.26 g (1.0 mmol) of BEI, 0.013 g of DOTDD (0.01 times the total mass of PFPE2 and BEI), and 1.30 g of MEK were charged. This mixture was stirred at room temperature (about 23 ° C.) for 24 hours using a stirrer tablet to obtain a 50% by mass MEK solution of the target compound, SM3.
The weight average molecular weight measured by GPC of the obtained SM3 in terms of polystyrene: Mw was 3,100, and the degree of dispersion: Mw / Mn was 1.1.

[Examples 2, 3, and Comparative Examples 1 to 3]
According to the description in Table 1, the following components were mixed to prepare a hardenable composition having a solid content concentration described in Table 1. In addition, a solid content means a component other than a solvent. In addition, [part] in the table means [mass part].
(1) Polyfunctional monomer: 100 parts by mass of the polyfunctional monomer described in Table 1
(2) Surface modifier: The surface modifier described in Table 1 is expressed in the amount (solid content conversion) described in Table 1.
(3) Polymerization initiator: I2959 5 parts by mass
(4) Solvent: 158 parts by mass of PGME was used to coat this hardenable composition on both sides of an A4 size easily-adhesive PET film [Lumirror (trademark registration) U403, manufactured by Toray Co., Ltd., thickness 100 μm] using a bar to obtain a coating membrane. This coating film was dried in an oven at 120 ° C for 3 minutes to remove the solvent. The obtained film was irradiated with UV light having an exposure amount of 300 mJ / cm ² under a nitrogen environment to be exposed, and a hard coating film having a hard coating layer (hardened film) having a film thickness of about 5 μm was produced.

The homogeneity of each hardenable composition and the appearance, scratch resistance, elongation, total light transmittance, haze, and contact angle of water of the obtained hard coating film were evaluated. The evaluation procedures of composition homogeneity, appearance, abrasion resistance, extensibility, and contact angle are shown below. The results are shown in Table 2.

[Composition homogeneity]
The appearance of the curable composition after 2 hours of preparation was visually confirmed, and evaluated based on the following criteria.
A: transparent solution
C: Cloudy

[Exterior]
The appearance of the hard coating film was visually confirmed, and evaluated according to the following criteria.
A: Through the hard coating layer, it is transparent and spot-free.
C: The hard coating layer is spotty and turbid throughout, making the spots stand out

[Scratch resistance]
The surface of the hard coating layer was wiped with a load of 250 g / cm ² for a round of 2,000 rounds with a stainless steel woolen spinning [Bonther (registered) Bonther (registered trademark) # 0000 (ultra-fine)) with a round-trip wear tester attached, which would cause scratches. The degree was confirmed visually and evaluated based on the following criteria. When a hard coating layer is assumed to be actually used, at least B can be obtained, and A is preferred.
A: No scars
B: Slightly scarred
C: full scar

[Extensibility]
A rectangular piece with a length of 80 mm and a width of 10 mm was taken out of the hard coating film, and a test piece was produced. From both ends in the longitudinal direction of the test piece, hold each 20mm with a gripper of a universal testing machine to take out the elongation (= (the increase in the distance between the grippers) ÷ (the distance between the grippers) × 100 ) The tensile test was performed at 5%, 10%, 15%, and 20%. The maximum elongation at which no crack occurred on the hard coating layer of the test piece was evaluated as elongation.

[Contact angle]
1 μL of water was adhered to the surface of the hard coating layer, 5 points of the contact angle θ after 5 seconds were measured, and the average value was used as the contact angle value.

【Table 1】

【Table 2】

As shown in Table 1, in the hard coating layer, each was used as a polyfunctional monomer to modify lactone-modified acrylate, and as a surface modifier, each of the two terminals had 4 acrylic fluorenyl groups through a urethane bond through each end. The hardening composition of perfluoropolyether SM1 (Example 2) or perfluoropolyether SM2 (Example 3) having two methacryl groups at each end via a urethane bond is transparent The solution and the hard coating film produced by using the hardening composition have excellent scratch resistance and moderate stretchability, and can obtain a transparent and spot-free appearance.

On the other hand, as a surface modifier, Comparative Example 2 of a perfluoropolyether SM3 having two acrylofluorenyl groups with a poly (oxyalkylene) group and one urethane bond at both ends was used. The composition is turbid and has poor homogeneity. Compared with the examples, the hard coating layer obtained from the composition has a deteriorated haze and a turbid appearance.
Moreover, as for Comparative Example 1 of each of the above-mentioned SM1 using an acrylate that has not been lactone-denatured as a polyfunctional monomer as a surface modifier, none of them had elongation.

As shown in the results of the examples above, the combination of a lactone-denatured polyfunctional monomer and a specific perfluoropolyether hardening composition can provide satisfactory scratch resistance, elongation, and appearance for the first time. Hard coating film.

Claims (17)

A hardening composition containing (a) 100 parts by mass of an active energy ray-curable lactone-denatured polyfunctional monomer, (b) a perfluoropolyether having an active energy ray polymerizable group via a urethane bond at both ends of a molecular chain containing a poly (oxyperfluoroalkylene) group (except 0.1 to 10 parts by mass of a perfluoropolyether having a poly (oxyalkylene) group between the (oxyperfluoroalkylene) group and the aforementioned urethane bond), and (c) active energy 1 to 20 parts by mass of a polymerization initiator for generating radicals. The curable composition according to claim 1, wherein the (b) perfluoropolyether has at least two active energy ray polymerizable groups on each of the two ends. The hardenable composition according to claim 2, wherein the (b) perfluoropolyether has at least three active energy ray polymerizable groups on each of the two ends. The curable composition according to any one of claims 1 to 3, wherein the aforementioned poly (oxyperfluoroalkylene) group is-[OCF ₂ ]-and-[OCF ₂ CF ₂ ]- Base. The hardenable composition according to claim 4, wherein the (b) perfluoropolyether has a partial structure represented by formula [1]; (In the formula, n represents the total number of repeating units-[OCF ₂ CF ₂ ]-and the number of repeating units-[OCF ₂ ]-, an integer of 5 to 30). The curable composition according to any one of claims 1 to 5, wherein the (a) polyfunctional monomer contains a polyfunctional (meth) acrylate compound modified with a lactone and a polyfunctional aminocarboxylic acid modified with a lactone At least one group of ester (meth) acrylate compounds. The curable composition according to any one of claims 1 to 6, wherein the (a) polyfunctional monomer is an ε-caprolactone-denatured polyfunctional monomer. The curable composition according to any one of claims 1 to 7, further comprising (d) a solvent. A cured film obtained by the curable composition according to any one of claims 1 to 8. A hard coating film having a hard coating layer on at least one side of a film substrate, characterized in that the hard coating layer is made of a hardened film as claimed in claim 9. A hard coating film, which is a hard coating film having a hard coating layer on at least one side of a film substrate, characterized in that the hard coating layer contains a hardening composition according to any one of claims 1 to 8 It is formed by the steps of applying a substance to a film substrate to form a coating film, and the step of irradiating the coating film with active energy rays to harden it. The hard coating film according to claim 10 or 11, wherein the hard coating layer has a film thickness of 1 to 10 μm. Poly (oxyperfluoroalkylene) -containing molecular chains have at least three active energy ray polymerizable groups at each end of each of the molecular chains (except for the poly (oxy group) Other than a perfluoropolyether compound having a poly (oxyalkylene) group between the perfluoroalkylene group and the aforementioned urethane bond). A perfluoropolyether compound according to claim 13, wherein the poly (oxyperfluoroalkylene) group is a group having-[OCF ₂ ]-and-[OCF ₂ CF ₂ ]-as repeating units. The perfluoropolyether compound according to claim 14, characterized in that it has a partial structure represented by formula [1]; (In the formula, n is the total of the number of repeating units-[OCF ₂ CF ₂ ]-and the number of repeating units-[OCF ₂ ]-, and represents an integer of 5 to 30.) A performance modifier comprising a perfluoropolyether compound according to any one of claims 13 to 15. A use of a perfluoropolyether compound according to any one of claims 13 to 15 for surface modification.