JP7401854B2 - Manufacturing method of scratch-resistant hard coat film - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing a hard coat film with excellent scratch resistance, and more particularly, to a method for producing a hard coat film having excellent scratch resistance.

Many electronic devices such as home appliances such as televisions, communication devices such as mobile phones, office equipment such as copy machines, entertainment devices such as game consoles, medical devices such as X-ray imaging devices, and household appliances such as microwave ovens, etc. A touch panel display using a liquid crystal display element or an OLED (organic EL) display element that can be operated by a person with a finger is provided. These touch panel displays are equipped with scratch-resistant hardware on the outermost surface of the touch panel to prevent scratches on the surface of the touch panel from fingernails, etc. when a person operates with their fingers. A hard coat film is provided which has a coating layer on a transparent plastic film as a base material.

On the other hand, in recent years, in order to improve the design of electronic devices as described above, designs in which the touch panel display portion is curved are sometimes adopted. When curved with the touch panel side facing outward, stress in the tensile direction is generated in the outermost hard coat layer. Therefore, the hard coat layer is required to have a certain degree of stretchability.

A general method for forming a hard coat layer is to use a polyfunctional acrylate as the main ingredient, a photopolymerization initiator to cause a curing reaction by radical polymerization of the polyfunctional acrylate using active energy rays, and dilute these to impart coating properties. A hard coat liquid containing an organic solvent for coating is applied to a substrate, and after removing the organic solvent by heating and drying, a hard coat layer is obtained by curing by irradiation with active energy rays. However, materials based on polyfunctional acrylates have low molecular mobility and resistance to external forces due to their high crosslinking density, so although they can provide scratch resistance, they usually do not have stretchability. .

Therefore, in order to impart a certain level of scratch resistance and stretchability to the hard coat layer, for example, a polyfunctional acrylate oligomer with a molecular weight of about 1,000 to 10,000 and an adjusted acrylate group density, or a polyfunctional urethane A method using acrylate oligomers is adopted. These polyfunctional acrylate oligomers have a crosslinking site and a stretching site in their molecular structure, and can exhibit appropriate abrasion resistance and stretchability due to the molecular mobility of the stretching site. As such a polyfunctional acrylate oligomer, a hard coat layer using polycaprolactone-modified polyfunctional acrylate has been disclosed (Patent Document 1).

Furthermore, as a method of imparting antifouling properties and slipperiness to the surface of the hard coat layer, a method of adding a small amount of a fluorine-based surface modifier to the coating liquid forming the hard coat layer is used. The added fluorine-based surface modifier segregates on the surface of the hard coat layer due to its low surface energy, imparting water repellency and oil repellency. The fluorine-based surface modifier is a perfluoropolyether having a poly(oxyperfluoroalkylene) chain from the viewpoint of water repellency and oil repellency. An oligomer having a number average molecular weight of about 0.000 is used. However, since these perfluoropolyethers have a high fluorine concentration, their solubility in organic solvents is specific, and it has been possible to use only limited organic solvents.

International Publication No. 2013/191254

An object of the present invention is to provide a method for manufacturing a hard coat film having excellent scratch resistance.

As a result of intensive studies to solve the above problems, the present inventors have discovered a process of applying a curable composition capable of forming a hard coat layer onto a film base material to form a coating film, and In the method for producing a scratch-resistant hard coat film, which includes at least a step of curing by irradiating active energy rays, the solvent contained in the curable composition has a solvent swelling degree of the film base material of 70% at its standard boiling point. It was discovered that a hard coat film having excellent scratch resistance could be produced by selecting the following, and the present invention was completed.
Furthermore, the present inventors have also discovered that by using a suitable film base material, it is possible to produce a hard coat film that has not only excellent scratch resistance but also stretchability.

That is, the present invention, as a first aspect, includes a step of applying a curable composition capable of forming a hard coat layer onto a film base material to form a coating film, and a step of curing the coating film by irradiating the coating film with active energy rays. A method for producing a scratch-resistant hard coat film comprising at least the following, wherein the solvent contained in the curable composition is a solvent in which the degree of solvent swelling of the film base material at its normal boiling point is 70% or less. The present invention relates to a method for producing an abrasion-resistant hard coat film.
A second aspect relates to the manufacturing method according to the first aspect, wherein the film base material is a thermoplastic polyurethane film.
As a third aspect, the curable composition includes:
(a) 100 parts by mass of an oxyalkylene-modified polyfunctional monomer having at least three active energy ray polymerizable groups;
(b) 0.1 part by mass of perfluoropolyether in which both ends of the molecular chain containing a poly(oxyperfluoroalkylene) group are modified with an organic group, with or without a poly(oxyalkylene) group; 10 parts by mass and (c) 1 to 20 parts by mass of a polymerization initiator that generates radicals by active energy rays.
As a fourth aspect, (b) perfluoropolyether in which both ends of the molecular chain containing a poly(oxyperfluoroalkylene) group are modified with an organic group, with or without a poly(oxyalkylene) group. relates to the method for producing a perfluoropolyether selected from the following (b1) to (b6) according to the third aspect.
(b1) Perfluorocarbons in which both ends of the molecular chain containing a poly(oxyperfluoroalkylene) group are modified with alcohol, piperonyl, carboxylic acid, or ester, with or without poly(oxyalkylene) groups. Polyether (b2) A polyether (b2) in which an alkoxysilyl group is bonded to both ends of a molecular chain containing a poly(oxyperfluoroalkylene) group via a poly(oxyalkylene) group and further via a divalent linking group. Fluoropolyether (b3) A perfluoropolyether (b4) in which an alkoxysilyl group is bonded to both ends of a molecular chain containing a poly(oxyperfluoroalkylene) group via a linking structure that does not have a poly(oxyalkylene) structure. ) has an active energy ray polymerizable group via a poly(oxyalkylene) group at one end of a molecular chain containing a poly(oxyperfluoroalkylene) group, and a poly(oxyalkylene) group at the other end of the molecular chain. Perfluoropolyether (b5) with a hydroxy group via a poly(oxyalkylene) group or a poly(oxyalkylene) group and one urethane at both ends of the molecular chain containing a poly(oxyperfluoroalkylene) group Through bonds in this order, perfluoropolyether (b6) having active energy ray polymerizable groups is attached to both ends of the molecular chain containing poly(oxyperfluoroalkylene) groups through urethane bonds. (However, perfluoropolyethers having a poly(oxyalkylene) group between the poly(oxyperfluoroalkylene) group and the urethane bond are excluded.)
As a fifth aspect, (b) perfluoropolyether in which both ends of the molecular chain containing a poly(oxyperfluoroalkylene) group are modified with an organic group, with or without a poly(oxyalkylene) group. (b6) A perfluoropolyether having an active energy ray polymerizable group via a urethane bond at both ends of the molecular chain containing the poly(oxyperfluoroalkylene) group (however, the above poly(oxyperfluoroalkylene) (excluding perfluoropolyethers having a poly(oxyalkylene) group between the urethane bond and the urethane bond).
As a sixth aspect, the solvent contained in the curable composition is selected from methanol, ethanol, n-propanol, isopropyl alcohol, n-butanol, isobutyl alcohol, tert-butyl alcohol, 2-ethylhexyl alcohol, benzyl alcohol, and ethylene glycol. The method according to any one of the first to fifth aspects, wherein the alcohol is one or more alcohols selected from the group consisting of:
A seventh aspect relates to the manufacturing method according to the sixth aspect, wherein the solvent contained in the curable composition is methanol.

According to the present invention, it is possible to provide a method for producing a hard coat film having excellent scratch resistance.
Furthermore, by using a suitable film base material, it is also possible to provide a method for producing a hard coat film that has not only excellent scratch resistance but also stretchability.

The present invention provides an anti-scratch method comprising at least the steps of: applying a curable composition capable of forming a hard coat layer onto a film base material to form a coating film; and curing the coating film by irradiating the coating film with active energy rays. A method for producing a scratch-resistant hard coat film, wherein the solvent contained in the curable composition is a solvent in which the degree of solvent swelling of the film base material at its normal boiling point is 70% or less. Regarding the manufacturing method.
Below, the method for producing the scratch-resistant hard coat film of the present invention will be explained in detail.
<Curable composition>
The curable composition capable of forming a hard coat layer that can be used in the present invention is not particularly limited as long as it is a composition that can be cured by irradiation with active energy rays to form a hard coat layer, and conventionally known compositions can be used. can be used. Preferably,
(a) 100 parts by mass of an oxyalkylene-modified polyfunctional monomer having at least three active energy ray polymerizable groups;
(b) 0.1 part by mass of perfluoropolyether in which both ends of the molecular chain containing a poly(oxyperfluoroalkylene) group are modified with an organic group, with or without a poly(oxyalkylene) group; Examples include curable compositions containing 10 parts by mass and (c) 1 to 20 parts by mass of a polymerization initiator that generates radicals by active energy rays.
Each of the components (a) to (c) above will be explained below.

[(a) Oxyalkylene-modified polyfunctional monomer having at least three active energy ray polymerizable groups]
The oxyalkylene-modified polyfunctional monomer having at least three active energy ray polymerizable groups refers to an oxyalkylene-modified polyfunctional monomer that has at least three active energy ray polymerizable groups.
Preferred (a) oxyalkylene-modified polyfunctional monomers having at least three active energy ray polymerizable groups in the curable composition of the present invention include oxyalkylene modified polyfunctional monomers having at least three active energy ray polymerizable groups. The monomer is selected from the group consisting of meth)acrylate compounds and oxyalkylene-modified polyfunctional urethane (meth)acrylate compounds.
In addition, in this invention, a (meth)acrylate compound refers to both an acrylate compound and a methacrylate compound. For example, (meth)acrylic acid refers to acrylic acid and methacrylic acid.

(a) Examples of the oxyalkylene in the oxyalkylene-modified polyfunctional monomer having at least three active energy ray polymerizable groups include oxyethylene and oxy(methylethylene), and preferred oxyalkylene-modified polyfunctional monomers include: Examples include oxyethylene-modified polyfunctional monomers.

Examples of the oxyalkylene-modified polyfunctional (meth)acrylate compounds include (meth)acrylate compounds of polyols modified with oxyethylene and oxy(methylethylene).
Examples of the polyol include glycerin, diglycerin, triglycerin, tetraglycerin, pentaglycerin, hexaglycerin, decaglycerin, polyglycerin, trimethylolpropane, ditrimethylolpropane, pentaerythritol, and dipentaerythritol.

(a) Examples of the active energy ray polymerizable groups in the oxyalkylene-modified polyfunctional monomer having at least three active energy ray polymerizable groups include (meth)acryloyloxy groups, vinyl groups, and epoxy groups.

(a) The number of oxyalkylenes such as oxyethylene and oxy(methylethylene) added to one molecule of the oxyalkylene-modified polyfunctional monomer having at least three active energy ray polymerizable groups is 1 to 30, preferably 1 to 12. It is.

In the present invention, the above (a) oxyalkylene-modified polyfunctional monomer having at least three active energy ray polymerizable groups can be used alone or in combination of two or more.

Preferred (a) oxyalkylene-modified polyfunctional monomer having at least three active energy ray-polymerizable groups is (a1) an oxyethylene-modified polyfunctional monomer having at least three active energy ray-polymerizable groups, with an average An oxyethylene-modified polyfunctional monomer (simply referred to as (a1) an oxyethylene-modified polyfunctional monomer having at least three active energy ray polymerizable groups) whose ethylene modification amount is less than 3 mol per 1 mol of the polymerizable group. Can be mentioned.
Preferred (a1) oxyethylene-modified polyfunctional monomer having at least three active energy ray polymerizable groups in the curable composition capable of forming a hard coat layer has at least three active energy ray polymerizable groups and has an average Examples include monomers selected from the group consisting of oxyethylene-modified polyfunctional (meth)acrylate compounds and oxyethylene-modified polyfunctional urethane (meth)acrylate compounds, in which the amount of oxyethylene modification is less than 3 mol per 1 mol of the polymerizable group. .

(a1) The average amount of oxyethylene modification in the oxyethylene-modified polyfunctional monomer having at least three active energy ray polymerizable groups is less than 3 mol per 1 mol of active energy ray polymerizable groups in the monomer, and preferably It is less than 2 mol per mol of active energy ray polymerizable group possessed by the monomer.
In addition, (a) the average amount of oxyethylene modification in the oxyethylene-modified polyfunctional monomer having at least three active energy ray polymerizable groups is greater than 0 mol per mol of the active energy ray polymerizable groups possessed by the monomer, preferably The amount is 0.1 mol or more, more preferably 0.5 mol or more, per 1 mol of the active energy ray polymerizable group contained in the monomer.

Examples of the oxyethylene-modified polyfunctional (meth)acrylate compound include (meth)acrylate compounds of polyols modified with oxyethylene.

(a1) The number of oxyethylenes added to one molecule of the oxyethylene-modified polyfunctional monomer having at least three active energy ray polymerizable groups is 1 to 30, preferably 1 to 12.

[(b) Perfluoropolyether in which both ends of a molecular chain containing a poly(oxyperfluoroalkylene) group are modified with an organic group, with or without a poly(oxyalkylene) group]
Component (b) serves as a surface modifier in the hard coat layer to which the curable composition of the present invention is applied. In addition, component (b) has excellent compatibility with component (a), thereby suppressing cloudiness of the hard coat layer and making it possible to form a hard coat layer with a transparent appearance.
Preferred organic groups in component (b) include, for example, alcohol (hydroxy group), piperonyl group, carboxylic acid (carboxy group), ester (alkoxycarbonyl group, acyloxy group), alkoxysilyl group, and active energy ray polymerizable group. Can be mentioned.
(b) Both ends of the molecular chain containing a poly(oxyperfluoroalkylene) group may be used in a curable composition capable of forming a hard coat layer, with or without a poly(oxyalkylene) group. The perfluoropolyether modified with an organic group can be selected from, for example, the following (b1) to (b6) (hereinafter also referred to as perfluoropolyethers (b1) to (b6)).
(b1) Perfluorocarbons in which both ends of the molecular chain containing a poly(oxyperfluoroalkylene) group are modified with alcohol, piperonyl, carboxylic acid, or ester, with or without poly(oxyalkylene) groups. Polyether (b2) A polyether (b2) in which an alkoxysilyl group is bonded to both ends of a molecular chain containing a poly(oxyperfluoroalkylene) group via a poly(oxyalkylene) group and further via a divalent linking group. Fluoropolyether (b3) A perfluoropolyether (b4) in which an alkoxysilyl group is bonded to both ends of a molecular chain containing a poly(oxyperfluoroalkylene) group via a linking structure that does not have a poly(oxyalkylene) structure. ) has an active energy ray polymerizable group via a poly(oxyalkylene) group at one end of a molecular chain containing a poly(oxyperfluoroalkylene) group, and a poly(oxyalkylene) group at the other end of the molecular chain. Perfluoropolyether (b5) with a hydroxy group via a poly(oxyalkylene) group or a poly(oxyalkylene) group and one urethane at both ends of the molecular chain containing a poly(oxyperfluoroalkylene) group Through bonds in this order, perfluoropolyether (b6) having active energy ray polymerizable groups is attached to both ends of the molecular chain containing poly(oxyperfluoroalkylene) groups through urethane bonds. (However, perfluoropolyethers having a poly(oxyalkylene) group between the poly(oxyperfluoroalkylene) group and the urethane bond are excluded.)

The number of carbon atoms in the alkylene group in the poly(oxyperfluoroalkylene) group that can be used in the perfluoropolyethers (b1) to (b6) is not particularly limited, but is preferably 1 to 4 carbon atoms. That is, the poly(oxyperfluoroalkylene) group refers to a group having a structure in which divalent fluorinated carbon groups having 1 to 4 carbon atoms and oxygen atoms are alternately connected; It refers to a group having a structure in which a divalent fluorinated carbon group numbered from 1 to 4 and an oxygen atom are connected. Specifically, -[OCF ₂ ]-(oxyperfluoromethylene group), -[OCF ₂ CF ₂ ]-(oxyperfluoroethylene group), -[OCF ₂ CF ₂ CF ₂ ]-(oxyperfluoropropane) -1,3-diyl group) and -[OCF ₂ C(CF ₃ )F]-(oxyperfluoropropane-1,2-diyl group).
The above oxyperfluoroalkylene groups may be used alone or in combination of two or more types, and in that case, the bonding of multiple types of oxyperfluoroalkylene groups is a block bond or a random bond. It may be any of the following.

Among these, from the viewpoint of obtaining a cured film with good scratch resistance, -[OCF ₂ ]-(oxyperfluoromethylene group) and -[OCF ₂ CF ₂ ] are used as poly(oxyperfluoroalkylene) groups. It is preferable to use a group having both -(oxyperfluoroethylene group) as repeating units.
Among them, as the above-mentioned poly(oxyperfluoroalkylene) group, repeating units: -[OCF ₂ ]- and -[OCF ₂ CF ₂ ]- are in a molar ratio of [repeating units: -[OCF ₂ ]-]: [repeating Unit: -[OCF ₂ CF ₂ ]-] is preferably a group containing the unit in a ratio of 2:1 to 1:2, and more preferably a group containing the unit in a ratio of approximately 1:1. The combination of these repeating units may be either block combination or random combination.
The total number of repeating units of the oxyperfluoroalkylene group is preferably in the range of 5 to 30, more preferably in the range of 7 to 21.
Further, the weight average molecular weight (Mw) of the poly(oxyperfluoroalkylene) group measured in terms of polystyrene by gel permeation chromatography (GPC) is 1,000 to 5,000, preferably 1,500 to 3, 000, or 1,500 to 2,000.

The number of carbon atoms in the alkylene group in the poly(oxyalkylene) group that can be used in perfluoropolyethers (b1), (b2), (b4) and (b5) is not particularly limited, but preferably 1 to 4 carbon atoms. It is. That is, the above-mentioned poly(oxyalkylene) group refers to a group having a structure in which an alkylene group having 1 to 4 carbon atoms and an oxygen atom are alternately connected, and the oxyalkylene group refers to a group having a structure in which an alkylene group having 1 to 4 carbon atoms and an oxygen atom are alternately connected. Refers to a group having a structure in which a group and an oxygen atom are connected. Examples of the alkylene group include ethylene group, 1-methylethylene group, trimethylene group, and tetramethylene group.
The above oxyalkylene groups may be used alone or in combination of two or more types, and in that case, the bond between the multiple types of oxyalkylene groups may be either a block bond or a random bond. It's okay.
Among these, the poly(oxyalkylene) group is preferably a poly(oxyethylene) group.
The number of repeating units of the oxyalkylene group in the poly(oxyalkylene) group is, for example, in the range of 1 to 15, preferably in the range of 5 to 12, and more preferably in the range of 7 to 12.

Examples of active energy ray polymerizable groups that can be used in perfluoropolyethers (b4) to (b6) include (meth)acryloyl groups, urethane (meth)acryloyl groups, and vinyl groups; The polymerizable group is not limited to one having one active energy ray polymerizable moiety such as a (meth)acryloyl moiety, but may have two or more active energy ray polymerizable moieties.

In the present invention, (b) perfluoropolyether in which both ends of a molecular chain containing a poly(oxyperfluoroalkylene) group are modified with an organic group with or without a poly(oxyalkylene) group is the above-mentioned perfluoropolyether. It is desirable to use 0.1 parts by mass to 10 parts by mass, preferably 0.2 parts by mass to 5 parts by mass, per 100 parts by mass of component (a).

Each of the perfluoropolyethers (b1) to (b6) will be explained in more detail below.

[(b1) Both ends of the molecular chain containing a poly(oxyperfluoroalkylene) group are alcohol-modified, piperonyl-modified, carboxylic acid-modified, or ester-modified with or without a poly(oxyalkylene) group. Fluoropolyether]
The alcohol-modified, piperonyl-modified, carboxylic acid-modified or ester-modified perfluoropolyether in perfluoropolyether (b1) refers to perfluoropolyether modified with alcohol at both ends, perfluoropolyether modified with piperonyl at both ends, perfluoropolyether modified at both ends with carboxyl. Acid-modified perfluoropolyether and ester-modified perfluoropolyether at both ends are intended.

Specific examples of perfluoropolyether (b1) include the following.
- Alcohol denaturation at both ends: FOMBLIN (registered trademark) ZDOL 2000, FOMBLIN ZDOL 2500, FOMBLIN 4000, TX, ZTETRAOL 2000GT, FLUOROLINK (registered trademark) D10H, FOMBLIN E10H [all manufactured by Solvay Specialty Polymers];
- Piperonyl modification at both ends: FOMBLIN (registered trademark) AM2001, AM3001 [both manufactured by Solvay Specialty Polymers];
・Carboxylic acid modification at both ends: FLUOROLINK (registered trademark) C10 [manufactured by Solvay Specialty Polymers];
・Ester modification at both ends: FLUOROLINK (registered trademark) L10H [manufactured by Solvay Specialty Polymers];

上記式［１］中、Ｒ^１は炭素原子数１乃至５のアルキル基を表し、Ｒ^２は炭素原子数１乃至５のアルキル基又はフェニル基を表し、ａは１乃至３の整数を表す。[(b2) A perfluorinated compound in which an alkoxysilyl group is bonded to both ends of a molecular chain containing a poly(oxyperfluoroalkylene) group via a poly(oxyalkylene) group and further via a divalent linking group. polyether]
The alkoxysilyl group in the perfluoropolyether (b2) is preferably a group represented by the following formula [1].

In the above formula [1], R ¹ represents an alkyl group having 1 to 5 carbon atoms, R ² represents an alkyl group having 1 to 5 carbon atoms or a phenyl group, and a represents an integer of 1 to 3.

Examples of the divalent linking group include divalent groups such as alkylene groups having 1 to 5 carbon atoms, oxygen atoms, ester bonds, amide bonds, urethane bonds, and urea bonds, and groups combining these. can be mentioned.

上記式［２］中、Ｒ^１及びＲ^３はそれぞれ独立して炭素原子数１乃至５のアルキル基を表し、Ｒ^２及びＲ^４はそれぞれ独立して、炭素原子数１乃至５のアルキル基又はフェニル基を表し、ａ及びｂはそれぞれ独立して１乃至３の整数を表し、Ｌ^１乃至Ｌ^４はそれぞれ独立して炭素原子数１乃至５のアルキレン基を表し、Ｘ^１及びＸ^２はそれぞれ独立して、－ＯＣ（＝Ｏ）－、－ＯＣ（＝Ｏ）ＮＨ－、－ＮＨＣ（＝Ｏ）－、－ＮＨＣ（＝Ｏ）ＮＨ－又は－Ｏ－を表し、ｍ及びｎはそれぞれｍ＋ｎが２乃至４０となる正の整数を表し、ＰＦＰＥ１はポリ（オキシパーフルオロアルキレン）構造を中核としてその両側にオキシアルキレン基と連結する末端構造を有する基を表す。The perfluoropolyether (b2) is preferably a compound represented by the following formula [2].

In the above formula [2], R ¹ and R ³ each independently represent an alkyl group having 1 to 5 carbon atoms, and R ² and R ⁴ each independently represent an alkyl group having 1 to 5 carbon atoms, or represents a phenyl group, a and b each independently represent an integer of 1 to 3, L ¹ to L ⁴ each independently represent an alkylene group having 1 to 5 carbon atoms, and X ¹ and X ² each independently represent an integer of 1 to 3; independently represents -OC(=O)-, -OC(=O)NH-, -NHC(=O)-, -NHC(=O)NH- or -O-, m and n each represent m+n represents a positive integer from 2 to 40, and PFPE1 represents a group having a poly(oxyperfluoroalkylene) structure at its core and terminal structures connected to oxyalkylene groups on both sides thereof.

Specific examples of the alkyl group having 1 to 5 carbon atoms in R ¹ and R ³ include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group. , tert-butyl group, n-pentyl group, isopentyl group, neopentyl group, tert-pentyl group, sec-pentyl group, 3-pentyl group, and cyclopentyl group.
Among these specific examples, R ¹ and R ³ are preferably a methyl group or an ethyl group.

Specific examples of the alkyl group having 1 to 5 carbon atoms for R ² and R ⁴ include the groups exemplified for R ¹ and R ³ above.
R ² and R ⁴ are preferably a methyl group or a phenyl group.

The above a and b are preferably 3.

Specific examples of alkylene groups having 1 to 5 carbon atoms in L ¹ to L ⁴ include, for example, methylene group, ethylene group, trimethylene group, methylethylene group, tetramethylene group, 1-methyltrimethylene group, 2- Methyltrimethylene group, 1,1-dimethylethylene group, pentamethylene group, 1-methyltetramethylene group, 2-methyltetramethylene group, 1,1-dimethyltrimethylene group, 1,2-dimethyltrimethylene group, 2 , 2-dimethyltrimethylene group, and 1-ethyltrimethylene group.
Among these specific examples, L ¹ and L ² are preferably an ethylene group or a trimethylene group, and more preferably a trimethylene group.
Furthermore, L ³ and L ⁴ are preferably an ethylene group or a methylethylene group, more preferably an ethylene group. That is, the oxyalkylene group represented as (L ₃ O) or (OL ₄ ) is preferably an oxyethylene group.

The above X ¹ and X ² are preferably -OC(=O)- or -OC(=O)NH-, more preferably -OC(=O)NH-, and even more preferably *-OC (=O)NH- (in the formula, * represents a bonding end with (L ³ O) _m or (OL ⁴ ) _n ).

Moreover, it is preferable that m and n are each positive integers such that m+n is 12 to 20.

PFPE1 represents a group having a poly(oxyperfluoroalkylene) structure at its core and terminal structures connected to oxyalkylene groups on both sides thereof.
Suitable examples of the poly(oxyperfluoroalkylene) structure include the groups specifically mentioned in the poly(oxyperfluoroalkylene) group described above.
The terminal structure that connects to the oxyalkylene groups present on both sides is, for example, **- (1 to 3 fluorine atoms) when bonding to the -O-terminus of the poly(oxyperfluoroalkylene) group. Substituted alkylene group having 2 or 3 carbon atoms)- or **-CF ₂ C(=O)- is the fluoroalkylene terminal of the poly(oxyperfluoroalkylene) group (for example, -CF ₂ -, -C(CF ₃ )F-), **-O-(alkylene group having 2 or 3 carbon atoms substituted with 1 to 3 fluorine atoms)-, or **- O-CF ₂ C(=O)- (**in each case represents a bonding end with a poly(oxyperfluoroalkylene) group).
Examples of the alkylene group having 2 or 3 carbon atoms substituted with 1 to 3 fluorine atoms include -CHFCH ₂ -, -CF ₂ CH ₂ -, -CF ₂ CHF-, -CHFCH ₂ CH ₂ - , -CF ₂ CH ₂ CH ₂ -, and -CF ₂ CHFCH ₂ -, with -CF ₂ CH ₂ - being preferred.

In the curable composition capable of forming a hard coat layer, one type of perfluoropolyether (b2) may be used alone, or two or more types may be used in combination.

The perfluoropolyether (b2) is, for example, a compound having hydroxy groups at both ends of a molecular chain containing a poly(oxyperfluoroalkylene) group via a poly(oxyalkylene) group. It can be obtained, for example, by a method of reacting an alkoxysilane having an isocyanato group such as (3-isocyanatopropyl)trimethoxysilane.

[(b3) Perfluoropolyether in which an alkoxysilyl group is bonded to both ends of a molecular chain containing a poly(oxyperfluoroalkylene) group via a linking structure that does not have a poly(oxyalkylene) structure]
Examples of the above-mentioned poly(oxyperfluoroalkylene) group and alkoxysilyl group include the groups mentioned above for perfluoropolyether (b2). Furthermore, examples of the linking structure that does not have a poly(oxyalkylene) structure include the groups listed as "divalent linking group" in the above-mentioned perfluoropolyether (b2).

上記式［３］中、Ｒ^５及びＲ^７はそれぞれ独立して炭素原子数１乃至５のアルキル基を表し、Ｒ^６及びＲ^８はそれぞれ独立して、炭素原子数１乃至５のアルキル基又はフェニル基を表し、ｒ及びｓはそれぞれ独立して１乃至３の整数を表し、Ｌ^５及びＬ^６はそれぞれ独立して炭素原子数１乃至５のアルキレン基を表し、Ｘ^３及びＸ^４はそれぞれ独立して、－ＯＣ（＝Ｏ）－、－ＯＣ（＝Ｏ）ＮＨ－、－ＮＨＣ（＝Ｏ）－、－ＮＨＣ（＝Ｏ）ＮＨ－又は－Ｏ－を表し、ＰＦＰＥ２はポリ（オキシパーフルオロアルキレン）構造を中核としてその両側にＸ^３又はＸ^４と連結する末端構造を有する基を表す。The perfluoropolyether (b3) is preferably a compound represented by the following formula [3].

In the above formula [3], R ⁵ and R ⁷ each independently represent an alkyl group having 1 to 5 carbon atoms, and R ⁶ and R ⁸ each independently represent an alkyl group having 1 to 5 carbon atoms; represents a phenyl group, r and s each independently represent an integer of 1 to 3, L ⁵ and L ⁶ each independently represent an alkylene group having 1 to 5 carbon atoms, and X ³ and X ⁴ each independently represent an integer of 1 to 3; independently represents -OC(=O)-, -OC(=O)NH-, -NHC(=O)-, -NHC(=O)NH- or -O-, and PFPE2 represents a group having a core structure (fluoroalkylene) and terminal structures connected to X ³ or X ⁴ on both sides thereof.

In the above formula [3], examples of the alkyl group having 1 to 5 carbon atoms in R ⁵ and R ⁷ and R ⁶ and R ⁸ include the alkyl groups exemplified for R ¹ and R ³ above.
R ⁵ and R ⁷ are preferably a methyl group or an ethyl group.
R ⁶ and R ⁸ are preferably a methyl group or a phenyl group.
Further, the above r and s are preferably 3.

Specific examples of the alkylene group having 1 to 5 carbon atoms in L ⁵ and L ⁶ include the alkylene groups exemplified in L ¹ to L ⁴ described above.
Among the specific examples of the alkylene group, L ⁵ and L ⁶ are preferably an ethylene group or a trimethylene group, and more preferably a trimethylene group.

The above X ³ and X ⁴ are preferably -OC(=O)- or -OC(=O)NH-, more preferably -OC(=O)NH-, and even more preferably *- OC(=O)NH- (in the formula, * represents the bonding end with PFPE2).

PFPE2 represents a group having a poly(oxyperfluoroalkylene) structure at its core and terminal structures connected to X ³ or X ⁴ on both sides thereof.
Examples of the poly(oxyperfluoroalkylene) structure and the terminal structure connected to X ³ and X ⁴ present on both sides thereof include the structure exemplified in PFPE1 described above.

The perfluoropolyether (b3) is, for example, a compound having a hydroxy group at both ends of a group containing a poly(oxyperfluoroalkylene) group, for example, (3-isocyanato It is obtained by a method of reacting an alkoxysilane having an isocyanato group such as propyltrimethoxysilane.

In the curable composition of the present invention, perfluoropolyether (b3) may be used alone or in combination of two or more.

[(b4) One end of a molecular chain containing a poly(oxyperfluoroalkylene) group has an active energy ray polymerizable group via a poly(oxyalkylene) group, and the other end of the molecular chain has a poly(oxyalkylene) group. ) Perfluoropolyether having hydroxyl group via group]
The active energy ray polymerizable group is not limited to one having one active energy ray polymerizable moiety such as a (meth)acryloyl moiety, but may have two or more active energy ray polymerizable moieties, Examples include the structures of formulas [A1] to [A5] shown below, and structures in which the acryloyl group in these structures is replaced with a methacryloyl group.

Specific examples of such perfluoropolyether (b4) include the compounds shown below and compounds in which the acryloyl group in these compounds is replaced with a methacryloyl group. In addition, in the structural formula, A represents the structure represented by the above formula [A1] to formula [A5], and PFPE has a poly(oxyperfluoroalkylene) structure at its core and terminals connected to oxyalkylene groups on both sides. represents a group having a structure, n represents the number of repeating units of an oxyethylene group, and preferably represents a number of 1 to 10.
Suitable examples of the poly(oxyperfluoroalkylene) structure include the groups specifically mentioned in the poly(oxyperfluoroalkylene) group described above.
The terminal structure that connects to the oxyalkylene groups present on both sides is, for example, **- (1 to 3 fluorine atoms) when bonding to the -O-terminus of the poly(oxyperfluoroalkylene) group. Substituted alkylene group having 2 or 3 carbon atoms)- or **-CF ₂ C(=O)- is the fluoroalkylene terminal of the poly(oxyperfluoroalkylene) group (for example, -CF ₂ -, -C(CF ₃ )F-), **-O-(alkylene group having 2 or 3 carbon atoms substituted with 1 to 3 fluorine atoms)-, or **- O-CF ₂ C(=O)- (**in each case represents a bonding end with a poly(oxyperfluoroalkylene) group).
Examples of the alkylene group having 2 or 3 carbon atoms substituted with 1 to 3 fluorine atoms include -CHFCH ₂ -, -CF ₂ CH ₂ -, -CF ₂ CHF-, -CHFCH ₂ CH ₂ - , -CF ₂ CH ₂ CH ₂ -, -CF ₂ CHFCH ₂ -, etc., with -CF ₂ CH ₂ - being preferred.

The above perfluoropolyether (b4) is, for example, a compound having a hydroxy group at both ends of a poly(oxyperfluoroalkylene) group via a poly(oxyalkylene) group, and a hydroxy group at one end of the both ends. A method of subjecting 2-(meth)acryloyloxyethyl isocyanate to a urethanization reaction, a method of subjecting (meth)acrylic acid chloride or chloromethylstyrene to a dehydrochloric acid reaction, a method of subjecting (meth)acrylic acid to a dehydration reaction, itaconic anhydride It can be obtained by a method such as an esterification reaction.
Among these methods, in a compound having a hydroxy group at both ends of a poly(oxyperfluoroalkylene) group via a poly(oxyalkylene) group, 2- A method in which (meth)acryloyloxyethyl isocyanate is subjected to a urethanization reaction, or a method in which the hydroxy group is subjected to a dehydrochlorination reaction with (meth)acrylic acid chloride or chloromethylstyrene are particularly preferred in terms of easy reaction.

[(b5) Active energy is added to both ends of the molecular chain containing a poly(oxyperfluoroalkylene) group via a poly(oxyalkylene) group or via a poly(oxyalkylene) group and one urethane bond in this order. Perfluoropolyether having linear polymerizable group]
The active energy ray polymerizable group is not limited to one having one active energy ray polymerizable moiety such as a (meth)acryloyl moiety, but may have two or more active energy ray polymerizable moieties, Examples include the structures of formulas [A1] to [A5] described above, and structures in which the acryloyl group in these structures is replaced with a methacryloyl group.

ポリ（オキシパーフルオロアルキレン）構造は、前述のポリ（オキシパーフルオロアルキレン）基において具体的に挙げた基を好適な構造として挙げることができる。
またその両側に存在するオキシアルキレン基と連結する末端構造としては、例えば、ポリ（オキシパーフルオロアルキレン）基の－Ｏ－末端と結合する場合には＊＊－（フッ素原子１個乃至３個で置換された炭素原子数２又は３のアルキレン基）－、又は、＊＊－ＣＦ_２Ｃ（＝Ｏ）－が、ポリ（オキシパーフルオロアルキレン）基のフルオロアルキレン末端（例えば、－ＣＦ_２－、－Ｃ（ＣＦ_３）Ｆ－）と結合する場合には、＊＊－Ｏ－（フッ素原子１個乃至３個で置換された炭素原子数２又は３のアルキレン基）－、又は、＊＊－Ｏ－ＣＦ_２Ｃ（＝Ｏ）－（＊＊は何れもポリ（オキシパーフルオロアルキレン）基との結合端を表す）が挙げられる。
上記フッ素原子１個乃至３個で置換された炭素原子数２又は３のアルキレン基としては、例えば、－ＣＨＦＣＨ_２－、－ＣＦ_２ＣＨ_２－、－ＣＦ_２ＣＨＦ－、－ＣＨＦＣＨ_２ＣＨ_２－、－ＣＦ_２ＣＨ_２ＣＨ_２－、－ＣＦ_２ＣＨＦＣＨ_２－が挙げられ、－ＣＦ_２ＣＨ_２－が好ましい。As such perfluoropolyether (b5), compounds represented by the structural formulas shown below and compounds in which the acryloyl group in these compounds is replaced with a methacryloyl group are used, from the viewpoint of easy industrial production. This can be cited as a preferable example. In the structural formula, A represents one of the structures represented by the above formulas [A1] to [A5], and PFPE has a poly(oxyperfluoroalkylene) structure at its core and oxy-oxygen on both sides. represents a group having a terminal structure linked to an alkylene group, each n independently represents the number of repeating units of an oxyethylene group, preferably represents a number of 1 to 15, more preferably represents a number of 5 to 12, More preferably, it represents a number from 7 to 12.

Suitable examples of the poly(oxyperfluoroalkylene) structure include the groups specifically mentioned in the poly(oxyperfluoroalkylene) group described above.
The terminal structure that connects to the oxyalkylene groups present on both sides is, for example, **- (1 to 3 fluorine atoms) when bonding to the -O-terminus of the poly(oxyperfluoroalkylene) group. Substituted alkylene group having 2 or 3 carbon atoms)- or **-CF ₂ C(=O)- is the fluoroalkylene terminal of the poly(oxyperfluoroalkylene) group (for example, -CF ₂ -, -C(CF ₃ )F-), **-O-(alkylene group having 2 or 3 carbon atoms substituted with 1 to 3 fluorine atoms)-, or **- O-CF ₂ C(=O)- (**in each case represents a bonding end with a poly(oxyperfluoroalkylene) group).
Examples of the alkylene group having 2 or 3 carbon atoms substituted with 1 to 3 fluorine atoms include -CHFCH ₂ -, -CF ₂ CH ₂ -, -CF ₂ CHF-, -CHFCH ₂ CH ₂ - , -CF ₂ CH ₂ CH ₂ -, and -CF ₂ CHFCH ₂ -, with -CF ₂ CH ₂ - being preferred.

The perfluoropolyether (b5) used in the present invention has a poly(oxyalkylene) group and one urethane bonding group attached to both ends of the molecular chain containing a poly(oxyperfluoroalkylene) group in this order, i.e. , a poly(oxyalkylene) group is bonded to both ends of a molecular chain containing a poly(oxyperfluoroalkylene) group, and one urethane bonding group is bonded to each poly(oxyalkylene) group at both ends, Preferably, it is a perfluoropolyether in which active energy ray polymerizable groups are bonded to each urethane bond at both ends. Furthermore, in the perfluoropolyether, it is preferable that the active energy ray polymerizable group is a group having at least two or more active energy ray polymerizable moieties.

The above-mentioned perfluoropolyether (b5) is, for example, a compound having a hydroxy group at both ends of a poly(oxyperfluoroalkylene) group via a poly(oxyalkylene) group. - A method of urethanizing an isocyanate compound having a polymerizable group such as (meth)acryloyloxyethyl isocyanate or 1,1-bis((meth)acryloyloxymethyl)ethyl isocyanate, (meth)acrylic acid chloride or chloromethylstyrene It can be obtained by dehydrochlorination reaction of (meth)acrylic acid, dehydration reaction of (meth)acrylic acid, and esterification reaction of itaconic anhydride.
Among these methods, in a compound having a hydroxyl group at both ends of a poly(oxyperfluoroalkylene) group via a poly(oxyalkylene) group, 2-(meth)acryloyl is added to the hydroxyl group at both ends. A method in which an isocyanate compound having a polymerizable group such as oxyethyl isocyanate or 1,1-bis((meth)acryloyloxymethyl)ethyl isocyanate is subjected to a urethanization reaction, or a method in which the hydroxy group is reacted with (meth)acrylic acid chloride or A method in which chloromethylstyrene is subjected to a dehydrochloric acid reaction is particularly preferred because the reaction is easy.

[(b6) A perfluoropolyether having an active energy ray polymerizable group at both ends of the molecular chain containing a poly(oxyperfluoroalkylene) group via a urethane bond (provided that the above poly(oxyperfluoroalkylene) (Excluding perfluoropolyethers having a poly(oxyalkylene) group between the group and the urethane bond.)
The above perfluoropolyether (b6) is not limited to having one active energy ray polymerizable group such as a (meth)acryloyl group at both ends, but has two or more active energy ray polymerizable groups at both ends. For example, the terminal structures containing active energy ray polymerizable groups include the structures of formulas [A1] to [A5] described above, and structures in which the acryloyl group in these structures is replaced with a methacryloyl group. One example is structure.

（式［４］中、Ａは前記式［Ａ１］乃至式［Ａ５］で表される構造及びこれらの構造中のアクリロイル基をメタクリロイル基に置換した構造のうちの１つを表し、ＰＦＰＥは、ポリ（オキシパーフルオロアルキレン）構造を中核としてその両側にオキシアルキレン基と連結する末端構造を有する基を表し、ｎはそれぞれ独立して１乃至５の整数を表し、Ｌ^７は、ｎ＋１価のアルコールからＯＨを除いたｎ＋１価の残基を表す。）Examples of the perfluoropolyether (b6) include perfluoropolyethers having at least two active energy ray polymerizable groups at both ends, and perfluoropolyethers having at least three active energy ray polymerizable groups at each end. Ether is preferred.
Examples of such perfluoropolyether (b6) include a compound represented by the following formula [4].

(In formula [4], A represents one of the structures represented by the above formulas [A1] to [A5] and the structure in which the acryloyl group in these structures is replaced with a methacryloyl group, and PFPE is Represents a group having a poly(oxyperfluoroalkylene) structure as the core and terminal structures connected to oxyalkylene groups on both sides, where n each independently represents an integer from 1 to 5, and ^L7 represents n+1-valent alcohol. represents the n+1-valent residue obtained by removing OH.)

Suitable examples of the poly(oxyperfluoroalkylene) structure include the groups specifically mentioned in the poly(oxyperfluoroalkylene) group described above.
The terminal structure that connects to the oxyalkylene groups present on both sides is, for example, **- (1 to 3 fluorine atoms) when bonding to the -O-terminus of the poly(oxyperfluoroalkylene) group. Substituted alkylene group having 2 or 3 carbon atoms)- or **-CF ₂ C(=O)- is the fluoroalkylene terminal of the poly(oxyperfluoroalkylene) group (for example, -CF ₂ -, -C(CF ₃ )F-), **-O-(alkylene group having 2 or 3 carbon atoms substituted with 1 to 3 fluorine atoms)-, or **- O-CF ₂ C(=O)- (**in each case represents a bonding end with a poly(oxyperfluoroalkylene) group).
Examples of the alkylene group having 2 or 3 carbon atoms substituted with 1 to 3 fluorine atoms include -CHFCH ₂ -, -CF ₂ CH ₂ -, -CF ₂ CHF-, -CHFCH ₂ CH ₂ - , -CF ₂ CH ₂ CH ₂ -, and -CF ₂ CHFCH ₂ -, with -CF ₂ CH ₂ - being preferred.

（式［Ｂ１］乃至式［Ｂ１２］中、Ａは前記式［Ａ１］乃至式［Ａ５］で表される構造及びこれらの構造中のアクリロイル基をメタクリロイル基に置換した構造のうちの１つを表す。）
上記式［Ｂ１］乃至式［Ｂ１２］で表される構造の中で、式［Ｂ１］及び式［Ｂ２］がｎ＝１の場合に相当し、式［Ｂ３］乃至式［Ｂ６］がｎ＝２の場合に相当し、式［Ｂ７］乃至式［Ｂ９］がｎ＝３の場合に相当し、式［Ｂ１０］乃至式［Ｂ１２］がｎ＝５の場合に相当する。
これらの中でも、式［Ｂ３］で表される構造が好ましく、特に式［Ｂ３］と式［Ａ３］の組合せが好ましい。As the partial structure (A-NHC(=O)O) _n L ⁷ - in the compound represented by the above formula [4], for example, the structures represented by the following formulas [B1] to [B12] are Can be mentioned.

(In the formulas [B1] to [B12], A represents one of the structures represented by the above formulas [A1] to [A5] and the structures in which the acryloyl group in these structures is replaced with a methacryloyl group. represent.)
In the structures represented by the above formulas [B1] to [B12], formulas [B1] and [B2] correspond to the case where n=1, and formulas [B3] to [B6] correspond to the case where n=1. 2, equations [B7] to [B9] correspond to the case where n=3, and equations [B10] to [B12] correspond to the case where n=5.
Among these, the structure represented by formula [B3] is preferred, and the combination of formula [B3] and formula [A3] is particularly preferred.

式［５］で表される部分構造は、前記式［４］で表される化合物から、Ａ－ＮＨＣ（＝Ｏ）を除いた部分に相当する。
式［５］中のｎは、繰り返し単位－［ＯＣＦ_２ＣＦ_２］－の数と、繰り返し単位－［ＯＣＦ_２］－の数との総数を表し、５乃至３０の範囲が好ましく、７乃至２１の範囲がより好ましい。また、繰り返し単位－［ＯＣＦ_２ＣＦ_２］－の数と、繰り返し単位－［ＯＣＦ_２］－の数との比率は、２：１乃至１：２の範囲であることが好ましく、およそ１：１の範囲とすることがより好ましい。これら繰り返し単位の結合は、ブロック結合及びランダム結合の何れであってもよい。Preferable perfluoropolyether (b6) includes a compound having a partial structure represented by the following formula [5].

The partial structure represented by formula [5] corresponds to the part obtained by removing A-NHC (=O) from the compound represented by formula [4].
n in formula [5] represents the total number of repeating units -[OCF ₂ CF ₂ ]- and repeating units -[OCF ₂ ]-, and is preferably in the range of 5 to 30, preferably 7 to 21. The range is more preferable. Further, 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, approximately 1:1. It is more preferable to set it as the range of. The combination of these repeating units may be either block combination or random combination.

（式中、ＰＦＰＥ、Ｌ^７及びｎは、前記式［４］と同じ意味を表す。）で表される化合物の両末端に存在するヒドロキシ基に対して、重合性基を有するイソシアネート化合物、即ち、前記式［Ａ１］乃至式［Ａ５］で表される構造及びこれらの構造中のアクリロイル基をメタクリロイル基に置換した構造における結合手にイソシアナト基が結合した化合物（例えば、２－（メタ）アクリロイルオキシエチルイソシアネート、１，１－ビス（（メタ）アクリロイルオキシメチル）エチルイソシアネート）を反応させてウレタン結合を形成することにより得ることができる。The above perfluoropolyether (b6) is, for example, the following formula [6]

(In the formula, PFPE, L ⁷ and n represent the same meanings as in formula [4] above.) An isocyanate compound having a polymerizable group, i.e. , compounds represented by the above formulas [A1] to [A5] and structures in which the acryloyl group in these structures is replaced with a methacryloyl group and an isocyanato group is bonded to the bond (for example, 2-(meth)acryloyl It can be obtained by reacting oxyethyl isocyanate and 1,1-bis((meth)acryloyloxymethyl)ethyl isocyanate) to form a urethane bond.

Preferred perfluoropolyethers (b6) include, for example, perfluoropolyethers having at least three active energy ray polymerizable groups via urethane bonds at both ends of the molecular chain containing poly(oxyperfluoroalkylene) groups. Examples include polyether compounds (excluding perfluoropolyethers having a poly(oxyalkylene) group between the poly(oxyperfluoroalkylene) group and the urethane bond).
The above perfluoropolyether compound having polymerizable groups at both ends is preferably a compound having a partial structure represented by the above formula [5].

Preferred component (b) (perfluoropolyether) is perfluoropolyether (b6), that is, (b6) has a poly(oxyperfluoroalkylene) group at both ends of the molecular chain, via a urethane bond. Examples include perfluoropolyethers having an active energy ray polymerizable group (excluding perfluoropolyethers having a poly(oxyalkylene) group between the poly(oxyperfluoroalkylene) group and the urethane bond). .

[(c) Polymerization initiator that generates radicals by active energy rays]
In the curable composition capable of forming a hard coat layer, preferred polymerization initiators that generate radicals by active energy rays (hereinafter also simply referred to as "(c) polymerization initiator") include, for example, electron beams, ultraviolet rays, and X-rays. It is a polymerization initiator that generates radicals when exposed to active energy rays such as UV rays, especially when exposed to ultraviolet rays.
Examples of the polymerization initiator (c) include benzoins, alkylphenones, thioxanthones, azos, azides, diazos, o-quinone diazides, acylphosphine oxides, oxime esters, organic peroxides, Examples include benzophenones, biscoumarins, bisimidazoles, titanocenes, thiols, halogenated hydrocarbons, trichloromethyltriazines, and onium salts such as iodonium salts and sulfonium salts. These may be used alone or in combination of two or more.
Among the specific examples of the polymerization initiator (c), alkylphenones are preferably used in the present invention from the viewpoints of transparency, surface curability, and thin film curability. By using alkylphenones, a cured film with improved scratch resistance can be obtained.

Examples of the alkylphenones include 1-hydroxycyclohexylphenylketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 2-hydroxy-1-(4-(2-hydroxyethoxy)phenyl) α-hydroxy such as -2-methylpropan-1-one, 2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropionyl)benzyl)phenyl)-2-methylpropan-1-one, etc. Alkylphenones; 2-methyl-1-(4-(methylthio)phenyl)-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butan-1-one α-aminoalkylphenones such as; 2,2-dimethoxy-1,2-diphenylethan-1-one; and methyl phenylglyoxylate.

In the present invention, (c) the polymerization initiator is preferably 1 part by mass to 20 parts by mass, based on 100 parts by mass of the above-mentioned (a) oxyalkylene-modified polyfunctional monomer having at least three active energy ray polymerizable groups. It is desirable to use it in a proportion of 2 parts by mass to 10 parts by mass.

[(d) Solvent]
The curable composition that can form the hard coat layer further contains (d) a solvent, that is, it is in the form of a varnish (film-forming material).
The solvent contained in the curable composition is a solvent that causes the degree of solvent swelling of the film base material to be 70% or less at its standard boiling point. Furthermore, a solvent with a solvent swelling degree of 50% or less is preferred, and a solvent with a solvent swelling degree of 30% or less is more preferred.
Here, the degree of solvent swelling means a value calculated according to the following formula by measuring the mass immediately after immersion in a solvent near the boiling point and after drying using an analytical balance.
Solvent swelling degree [%] = (m ₁ - m ₀ ) ÷ m ₀ × 100
(m ₀ : mass of test piece dried after immersion in solvent, m ₁ : mass of test piece after immersion in solvent)
The above-mentioned solvent is appropriately selected in consideration of the ability to dissolve the components (a) to (c), and the workability during coating for forming a cured film (hard coat layer), drying properties before and after curing, etc., which will be described later. be done.
Examples of the above-mentioned solvents include aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene, and tetralin; aliphatic or alicyclic hydrocarbons such as n-hexane, n-heptane, mineral spirit, and cyclohexane; and methyl chloride. , methyl bromide, methyl iodide, dichloromethane, chloroform, carbon tetrachloride, trichloroethylene, perchloroethylene, o-dichlorobenzene and other halides; ethyl acetate, butyl acetate, methoxybutyl acetate, methyl cellosolve acetate, ethyl cellosolve acetate , esters or ester ethers such as 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 - Ethers such as propyl ether, propylene glycol monoisopropyl ether, and propylene glycol mono-n-butyl ether; Ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, di-n-butyl ketone, and cyclohexanone; methanol, ethanol, n-propanol, Alcohols such as isopropyl alcohol, n-butanol, isobutyl alcohol, tert-butyl alcohol, 2-ethylhexyl alcohol, benzyl alcohol, ethylene glycol; N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2- Examples include amides such as pyrrolidone; sulfoxides such as dimethyl sulfoxide; and a mixture of two or more of these solvents.
Examples of solvents when using a thermoplastic polyurethane (TPU) film as a film base material include methanol, ethanol, n-propanol, isopropyl alcohol, n-butanol, isobutyl alcohol, tert-butyl alcohol, 2-ethylhexyl alcohol, and benzyl. Examples include alcohols, alcohols such as ethylene glycol, and solvents obtained by mixing two or more of these solvents, with methanol being preferred.
(d) The amount of the solvent to be used is not particularly limited, but for example, the concentration at which the solid content concentration in the curable composition capable of forming a hard coat layer is 1% by mass to 70% by mass, preferably 5% by mass to 50% by mass. Use with. Here, the solid content concentration (also referred to as non-volatile content concentration) refers to the solid content (total mass) relative to the total mass (total mass) of the components (a) to (d) (and other additives if desired) of the curable composition. Represents the content of components (excluding solvent components).

[Other additives]
In addition, additives that are generally added as necessary to the curable composition capable of forming a hard coat layer, such as polymerization inhibitors, photosensitizers, leveling agents, etc., may be added as long as they do not impair the effects of the present invention. Agents, surfactants, adhesion agents, plasticizers, ultraviolet absorbers, antioxidants, storage stabilizers, antistatic agents, inorganic fillers, pigments, and dyes may be blended as appropriate.

The method for producing a scratch-resistant hard coat film according to the present invention includes a step of applying a curable composition capable of forming the above-mentioned hard coat layer onto a film base material to form a coating film, and applying active energy to the coating film. The method includes at least a step of curing by irradiating with a line.

Examples of the film base material include polyesters such as thermoplastic polyurethane (TPU), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), and polyethylene naphthalate (PEN), polycarbonate, polymethacrylate, polystyrene, polyolefin, polyamide, Examples include resin films selected from polyimide and triacetylcellulose, and preferably thermoplastic polyurethane (TPU) films from the viewpoint of scratch resistance and stretchability of the resulting hard coat film.
Thermoplastic polyurethane (TPU) films can exhibit excellent scratch resistance if a solvent in which the degree of solvent swelling of the thermoplastic polyurethane (TPU) film at its normal boiling point is 70% or less is used as a solvent in the curable composition. In addition to this, it is possible to produce a hard coat film that is also given stretchability.

Examples of the coating method on the film base material include cast coating, spin coating, blade coating, dip coating, roll coating, spray coating, bar coating, die coating, inkjet, and printing. (For example, letterpress printing method, intaglio printing method, planographic printing method, screen printing method) can be selected as appropriate. Among these methods, roll-to-roll method can be used, and thin film printing method can be used. From the viewpoint of coating properties, it is desirable to use a letterpress printing method, particularly a gravure coating method. Note that it is preferable to filter the curable composition in advance using a filter with a pore size of about 0.2 μm, and then apply it.

After the curable composition is applied onto the film base material to form a coating film, the coating film is pre-dried using a heating means such as a hot plate or an oven as necessary to remove the solvent (solvent removal step). The heating drying conditions at this time are preferably, for example, 40° C. to 120° C. and about 30 seconds to 10 minutes.

After drying, the coating film is cured by irradiation with active energy rays such as ultraviolet rays. Examples of active energy rays include ultraviolet rays, electron beams, and X-rays, with ultraviolet rays being particularly preferred. As the light source used for ultraviolet irradiation, for example, sunlight, chemical lamps, low pressure mercury lamps, high pressure mercury lamps, metal halide lamps, xenon lamps, and UV-LEDs can be used.
Furthermore, the polymerization may be completed by post-baking, specifically by heating using a heating means such as a hot plate or an oven.
The thickness of the hard coat layer thus obtained is preferably 1 μm to 20 μm, more preferably 1 μm to 10 μm.

By the method for producing a scratch-resistant hard coat film of the present invention, a hard coat film including a hard coat layer on at least one surface (surface) of a film base material can be produced. The hard coat film is suitably used, for example, to protect the surfaces of various display elements such as flexible displays.

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples.
In the examples, the apparatus and conditions used for sample preparation and physical property analysis are as follows.

(1) Hot plate stirrer device: IKA Plate manufactured by IKA Japan Co., Ltd.
(2) Application using bar coat Equipment: PM-9050MC manufactured by SMT Co., Ltd.
Bar: A-Bar OSP-22 manufactured by OSG System Products Co., Ltd., maximum wet film thickness 22 μm (equivalent to wire bar #9)
Coating speed: 4 m/min (3) Oven Equipment: Advantech Toyo Co., Ltd. dust-free dryer DRC433FA
(4) UV curing device: CV-110QC-G manufactured by Heraeus Co., Ltd.
Lamp: High pressure mercury lamp H-bulb manufactured by Heraeus Co., Ltd.
(5) Storage modulus measurement Device: Dynamic viscoelasticity automatic measuring device manufactured by A&D Co., Ltd. Rheovibron (registered trademark) DDV-01GP
Sample size: length 4mm x width 1mm
Measurement mode: Tensile Measurement temperature: 25℃
Measurement amplitude: 4μm
Measurement frequency: 10Hz
(6) Analytical balance device: XSE205 manufactured by METTLER TOLEDO Co., Ltd.
(7) Gel permeation chromatography (GPC)
Equipment: HLC-8220GPC manufactured by Tosoh Corporation
Column: Showa Denko K.K. Shodex (registered trademark) GPC K-804L, GPC K-805L
Column temperature: 40℃
Eluent: Tetrahydrofuran Detector: RI
(8) Scratch test Equipment: Reciprocating abrasion tester manufactured by Shinto Kagaku Co., Ltd. TRIBOGEAR TYPE: 30S
Scanning speed: 3,000mm/min Scanning distance: 50mm

In addition, the abbreviations represent the following meanings.
EOMA: Ethylene oxide modified polyfunctional acrylate [Aronix (registered trademark) MT-3553 manufactured by Toagosei Co., Ltd., number of functional groups 4 or more]
PFPE: Perfluoropolyether having two hydroxyl groups at each end without a poly(oxyalkylene) group [Fomblin (registered trademark) T4 manufactured by Solvay Specialty Polymers]
BEI: 1,1-bis(acryloyloxymethyl)ethyl isocyanate [Karens (registered trademark) BEI manufactured by Showa Denko K.K.]
DOTDD: Dioctyltin dineodecanoate [Neostane (registered trademark) U-830, manufactured by Nitto Kasei Co., Ltd.]
I2959: 2-hydroxy-1-(4-(2-hydroxyethoxy)phenyl)-2-methylpropan-1-one [IRGACURE (registered trademark) 2959, manufactured by BASF Japan Ltd.]
TPU1: Polyurethane elastomer film [Higress DUS270-CER manufactured by Seedam Co., Ltd., thickness 100 μm, storage modulus 92 MPa (actual value)]
TPU2: Polyurethane elastomer film [Higress DUS605-CER manufactured by Seedam Co., Ltd., thickness 100 μm, storage modulus 159 MPa (actual value)]
PMMA: Poly(methyl methacrylate) film [Technolloy S000 manufactured by Sumika Acrylic Sales Co., Ltd., thickness 125 μm]
MeOH: Methanol EtOH: Ethanol IPA: 2-propanol PGME: Propylene glycol monomethyl ether MEK: Methyl ethyl ketone MIBK: Methyl isobutyl ketone AcOEt: Ethyl acetate AcOBu: Butyl acetate

[Reference Example] Degree of Solvent Swelling of Film Base Material 50 mL of the solvents listed in Table 1 were placed in a 100 mL beaker and heated with a hot plate stirrer so that the liquid temperature was around the boiling point of the solvent. A test piece cut into a size of 25 mm x 25 mm was immersed in this for 3 minutes. After the immersion, the excess solvent adhering to the surface of the test piece is gently wiped off with a non-woven cloth wiper [BEMCOT (registered trademark) M-1 manufactured by Ozu Sangyo Co., Ltd.], and the test piece is immediately removed using an analytical balance. The mass m ₁ was measured. Next, this test piece was dried at room temperature (approximately 23° C.) for 24 hours, and the mass m ₀ of the test piece after drying was measured. The degree of solvent swelling was calculated using the following formula. The results are also shown in Table 1.
Solvent swelling degree [%] = (m ₁ - m ₀ ) ÷ m ₀ × 100

[Production Example 1] Production of perfluoropolyether (SM) having four acryloyl groups via urethane bonds at both ends In a screw tube, 1.19 g (0.5 mmol) of PFPE and 0.52 g (2.0 mmol) of BEI were added. , 0.017 g of DOTDD (0.01 times the total mass of PFPE and BEI), and 1.67 g of MEK were charged. This mixture was stirred for 24 hours at room temperature (approximately 23° C.) using a stirrer tip to obtain a 50% by mass MEK solution of SM, the target compound.
The weight average molecular weight (Mw) of the obtained SM measured in terms of polystyrene by GPC was 3,000, and the degree of dispersion: Mw (weight average molecular weight)/Mn (number average molecular weight) was 1.2.

[Example 1 to Example 4, Comparative Example 1 to Comparative Example 6]
The following components (1) to (4) were mixed to prepare a curable composition having a solid content concentration of 40% by mass. Note that the solid content here refers to components other than the solvent.
(1) Polyfunctional monomer: EOMA 100 parts by mass (2) Surface modifier: SM produced in Production Example 1 0.2 parts by mass (solid content equivalent)
(3) Polymerization initiator: 3 parts by mass of I2959 (4) Solvent: 154.6 parts by mass of the solvent listed in Table 2 This curable composition was bar coated on the film base material (B5 size) listed in Table 2. A coating film was obtained. This coating film was dried in an oven at the temperature listed in Table 2 for 3 minutes to remove the solvent. The obtained film was exposed to UV light at an exposure dose of 300 mJ/cm ² in a nitrogen atmosphere to produce a hard coat film having a hard coat layer (cured film) having a thickness of approximately 5 μm.

The surface of the obtained hard coat layer was rubbed reciprocatingly for 10 times with a load of 500 g/cm ² using steel wool [Bonstar (registered trademark) #0000 (ultra-fine) manufactured by Bonstar Sales Co., Ltd.] attached to a reciprocating abrasion tester. The degree of damage was visually confirmed and evaluated according to the following criteria. The results are also shown in Table 2. Note that when assuming actual use as a hard coat layer, at least B is required, and A is desirable.
A: No scratches B: Scratches less than 5 mm in length C: Scratches over 5 mm in length

As shown in Table 2, hard coat films (Examples 1 to 3) were prepared using MeOH, which is a solvent with a low solvent swelling degree of the film base used, that is, 70% or less, and hard coat films were prepared using AcOEt. It became clear that the hard coat film (Example 4) exhibited excellent scratch resistance. On the other hand, PGME (Comparative Examples 1 to 3) and MEK (Comparative Examples 4 to 6), which are solvents with a high degree of solvent swelling, that is, exceeding 70%, or solvents in which the film base material is completely dissolved, are used. It became clear that the scratch resistance of the hard coated film significantly decreased.

Claims (4)

A scratch-resistant hard coat film comprising at least the steps of applying a curable composition capable of forming a hard coat layer onto a film base material to form a coating film, and curing the coating film by irradiating the coating film with active energy rays. , wherein the solvent contained in the curable composition is a solvent in which the degree of solvent swelling of the film base material at its standard boiling point is 70% or less,
The curable composition includes:
(a) 100 parts by mass of an oxyalkylene-modified polyfunctional monomer having at least three active energy ray polymerizable groups;
(b) 0.1 to 10 parts by mass of perfluoropolyether , which is a compound represented by the following formula [4] ; and (c) 1 to 20 parts by mass of a polymerization initiator that generates radicals by active energy rays. A method for producing a scratch-resistant hard coat film, comprising :

(In formula [4], A represents the structure represented by the following formula [A3] or a structure in which the acryloyl group in the structure is replaced with a methacryloyl group, and PFPE has a poly(oxyperfluoroalkylene) structure as its core. Represents a group having a terminal structure connected to an oxyalkylene group on both sides, and the partial structure (A-NHC(=O)O) _n L ⁷ - is represented by the following formula [B3].

The manufacturing method according to claim 1, wherein the film base material is a thermoplastic polyurethane film or a poly(methyl methacrylate) film. The solvent contained in the curable composition is selected from the group consisting of methanol, ethanol, n-propanol, isopropyl alcohol, n-butanol, isobutyl alcohol, tert-butyl alcohol, 2-ethylhexyl alcohol, benzyl alcohol, and ethylene glycol. The manufacturing method according to claim 1 or 2, wherein the alcohol is one or more types of alcohol. The manufacturing method according to claim 3, wherein the solvent contained in the curable composition is methanol.