JP7373074B2 - Composition for forming hard coat layer, hard coat film, method for producing hard coat film, and article containing hard coat film - Google Patents

Description

The present invention relates to a composition for forming a hard coat layer, a hard coat film, a method for producing a hard coat film, and an article containing the hard coat film.

The composition for forming a hard coat layer can form a hard coat layer by applying it onto a substrate and curing it. For example, in image display devices such as liquid crystal displays (LCDs), plasma display panels (PDPs), electroluminescent displays (ELDs), micro LEDs (Light Emitting Diodes), and micro OLEDs (Organic Light Emitting Diodes), In order to prevent scratches on the substrate, it is preferable to provide an optical film having a hard coat layer (hard coat film) on the substrate, and a hard coat layer forming composition is used to form the hard coat layer. It is being

Patent Document 1 describes a method for manufacturing a structure having a concave pattern, in which a resin composition containing a polymer having an acid-dissociable group containing a fluorine atom and an acid generator is used to coat a non-flat surface of the structure. The process of forming is described.

Patent Document 2 describes an ultraviolet or electron beam curable hard coat composition containing a compound having a fluoroalkyl structure or a fluoropolyether structure, an epoxy group, and an acryloyl group.

International Publication No. 2016/039327 Japanese Patent Application Publication No. 2011-241190

However, the present inventors investigated and found that the surface of a hard coat film formed by using a conventional composition as a composition for forming a hard coat layer, applying it onto a base material, and curing it has an orange-skinned appearance. It was found that the surface quality was poor, with unevenness occurring. Furthermore, it has been found that when a scratch resistant layer is laminated on the hard coat layer in order to impart scratch resistance, sufficient scratch resistance cannot be obtained.
An object of the present invention is to provide a composition for forming a hard coat layer that can form a hard coat film with excellent surface condition and scratch resistance, and a hard coat formed using the composition for forming a hard coat layer. The object of the present invention is to provide a film, a method for producing the hard coat film, and an article containing the hard coat film.

The inventors of the present invention have made extensive studies and found that the above problem can be solved by the following means.

<1>
A polymer (S ) A composition for forming a hard coat layer.
<2>
The composition for forming a hard coat layer according to <1>, wherein the acid-cleavable group includes a group represented by the following general formula (1).

In general formula (1),
X ¹ and X ² each independently represent an oxygen atom or a sulfur atom.
R ¹ and R ² each independently represent a hydrogen atom or a substituent, and at least one of R ¹ and R ² represents a substituent. R ¹ and R ² may be combined to form a ring. At least one of R ¹ and R ² may be bonded to a moiety other than the group represented by general formula (1) of the structural unit (a) to form a ring.
m and n each independently represent 0 or 1. However, when R ¹ or R ² represents a hydrogen atom, n represents 1.
*1 and *2 represent bonding positions.
<3>
The composition for forming a hard coat layer according to <1> or <2>, wherein the structural unit (a) has an acetal structure, a thioacetal structure, or a dithioacetal structure.
<4>
The above acetal structure is a structure represented by the following general formula (AC1) or (AC2), the above thioacetal structure is a structure represented by the following general formula (SA1), (SA2) or (SA3), and the above The composition for forming a hard coat layer according to <3>, wherein the dithioacetal structure is represented by the following general formula (DS1) or (DS2).

In the general formulas (AC1), (SA1) and (DS1), R ¹ and R ² each independently represent a hydrogen atom or a substituent, and at least one of R ¹ and R ² represents a substituent. R ¹ and R ² may be combined to form a ring. At least one of R ¹ and R ² may be bonded to a moiety other than the structure represented by the general formula (AC1), (SA1) or (DS1) of the structural unit (a) to form a ring.
In the general formulas (AC2), (SA2), (SA3) and (DS2), R ³ represents a substituent, and k represents an integer of 0 to 3. When k represents 2 or 3, a plurality of R ³ 's may be the same or different.
In the general formulas (AC1), (AC2), (SA1), (SA2), (SA3), (DS1) and (DS2), * represents the bonding position.
<5>
The composition for forming a hard coat layer according to any one of <1> to <4>, wherein the number of fluorine atoms contained in the fluorine atom-containing group is 3 or more and 17 or less.
<6>
The content of the structural unit (a) in the polymer (S) is 3 mol% or more and less than 50 mol% of the total structural units contained in the polymer (S), <1> to <5 The composition for forming a hard coat layer according to any one of the above.
<7>
The composition for forming a hard coat layer according to any one of <1> to <6>, wherein the polymer (S) is a (meth)acrylic polymer or a polysilsesquioxane.
<8>
The hardener according to any one of <1> to <7>, wherein the cationically polymerizable group of the structural unit (b) is a group represented by any of the following general formulas (C1) to (C3). Composition for forming a coat layer.

In general formulas (C1) to (C3), * represents a bonding position. In general formula (C3), R _C represents a hydrogen atom or a substituent.
<9>
The composition for forming a hard coat layer according to any one of <1> to <8>, wherein the radically polymerizable group of the structural unit (c) is a (meth)acryloyl group.
<10>
A hard coat film comprising a plastic base material and a hard coat layer formed from the composition for forming a hard coat layer according to any one of <1> to <9>.
<11>
A method for producing a hard coat film comprising a base material and a hard coat layer, the method comprising applying the composition for forming a hard coat layer according to any one of <1> to <9> onto the base material. A method for producing a hard coat film, comprising forming a coating film and subjecting the coating film to a curing treatment to form the hard coat layer.
<12>
The method for producing a hard coat film according to <11>, wherein the curing treatment is a curing treatment using light and heat.
<13>
An article containing the hard coat film according to <10>.
<14>
The article according to <13>, comprising the hard coat film as a surface protection film.

According to the present invention, a hard coat layer forming composition capable of forming a hard coat film having excellent surface condition and scratch resistance, and a hard coat formed using the above hard coat layer forming composition. A film, a method for producing the hard coat film, and an article containing the hard coat film can be provided.

Hereinafter, embodiments for carrying out the present invention will be described in detail, but the present invention is not limited thereto.
In this specification, when numerical values represent physical property values, characteristic values, etc., the description "(numerical value 1) to (numerical value 2)" means "(numerical value 1) or more and (numerical value 2) or less".
In this specification, the term "(meth)acrylate" means "at least one of acrylate and methacrylate." The same applies to "(meth)acrylic acid", "(meth)acryloyl", etc.
In this specification, for each component, one type of substance corresponding to each component may be used alone, or two or more types may be used in combination. Here, when two or more types of substances are used together for each component, the content of the component refers to the total content of the substances used in combination, unless otherwise specified.
Further, the bonding direction of the divalent groups described in this specification is not particularly limited.

[Hard coat layer forming composition]
The composition for forming a hard coat layer of the present invention comprises a structural unit (a) containing a fluorine atom-containing group and an acid-cleavable group, a structural unit (b) containing a cationically polymerizable group, and a radically polymerizable group. A polymer (S) having a structural unit (c) containing

<Polymer (S)>
The polymer (S) contained in the composition for forming a hard coat layer of the present invention will be explained.
The main chain structure of the polymer (S) is not particularly limited, and may be any known main chain structure. Examples of the type of polymer (S) include (meth)acrylic polymer, styrene polymer, cycloolefin polymer, methylpentene polymer, aromatic polyester, (meth)acrylamide polymer, polysilsesquioxane, etc. ) Acrylic polymers, (meth)acrylamide polymers, or polysilsesquioxanes are preferable, and (meth)acrylic polymers or polysilsesquioxanes are more preferable.

[Structural unit (a) containing a fluorine atom-containing group and an acid-cleavable group]
The polymer (S) has a structural unit (a) (also simply referred to as "structural unit (a)") containing a fluorine atom-containing group and an acid-cleavable group.

(Group containing a fluorine atom)
The group containing a fluorine atom (also referred to as a "fluorine-containing group") contained in the structural unit (a) is a group containing at least one fluorine atom, for example, a fluorine atom, a group containing at least one fluorine atom, Examples include organic groups having The number of carbon atoms in the organic group is not particularly limited, but preferably 1 to 20 carbon atoms, more preferably 2 to 15 carbon atoms, even more preferably 4 to 10 carbon atoms, and 4 carbon atoms. It is particularly preferable that the number is 8 to 8. The above organic group may have a linear structure, a branched structure, or a cyclic structure. Examples of the organic group include an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an alkynyl group, a cycloalkynyl group, an alkoxy group, an aryl group, an aryloxy group, and a group formed by combining at least two of these groups. are mentioned, and an alkyl group is preferable. Further, the above alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, alkynyl group, cycloalkynyl group, alkoxy group, aryl group, and aryloxy group may have a substituent other than the fluorine atom.
The fluorine-containing group is preferably a fluoroalkyl group or a fluoropolyether group. A fluoropolyether group is a divalent group in which a plurality of fluorocarbon groups are bonded through ether bonds. The fluoropolyether group is preferably a divalent group in which multiple fluoroalkylene groups are bonded via ether bonds, and the fluoropolyether group is preferably a divalent group in which multiple perfluoroalkylene groups are bonded via ether bonds (perfluoropolyether group) is preferable.
The fluorine-containing group is preferably a fluoroalkyl group having 1 to 20 carbon atoms, more preferably a fluoroalkyl group having 2 to 15 carbon atoms, and even more preferably a fluoroalkyl group having 4 to 10 carbon atoms. Preferably, a fluoroalkyl group having 4 to 8 carbon atoms is particularly preferable.
The number of fluorine atoms contained in one fluorine-containing group is preferably 3 or more and 17 or less, more preferably 5 or more and 15 or less, and even more preferably 9 or more and 13 or less. preferable.

The fluorine-containing group is preferably a group represented by the following general formula (f-1).

In the general formula (f-1), q1 represents an integer of 0 to 12, q2 represents an integer of 1 to 8, and Rq ₁ represents a hydrogen atom or a fluorine atom. * represents the bonding position.
q1 preferably represents an integer of 1 to 7, more preferably an integer of 1 to 5, and even more preferably 1 or 2.
q2 preferably represents an integer of 2 to 8, more preferably an integer of 4 to 8, even more preferably an integer of 4 to 6.
Preferably, Rq ₁ represents a fluorine atom.

(Acid-cleavable group)
The acid-cleavable group contained in the structural unit (a) is a group that is cleaved by the action of an acid, and is typically a group that is cleaved by the action of an acid to produce a polar group (e.g., a hydroxy group, a carboxy group, etc.). It is.
The acid-cleavable group preferably includes a group represented by the following general formula (1).

In general formula (1),
X ¹ and X ² each independently represent an oxygen atom or a sulfur atom.
R ¹ and R ² each independently represent a hydrogen atom or a substituent, and at least one of R ¹ and R ² represents a substituent. R ¹ and R ² may be combined to form a ring. At least one of R ¹ and R ² may be bonded to a moiety other than the group represented by general formula (1) of the structural unit (a) to form a ring.
m and n each independently represent 0 or 1. However, when R ¹ or R ² represents a hydrogen atom, n represents 1.
*1 and *2 represent bonding positions.

In general formula (1), X ¹ and X ² each independently represent an oxygen atom or a sulfur atom, and preferably represent an oxygen atom.

In general formula (1), R ¹ and R ² each independently represent a hydrogen atom or a substituent. When R ¹ and R ² represent a substituent, the type of the substituent is not particularly limited and may be any known substituent. Examples of substituents include alkyl groups, cycloalkyl groups, alkenyl groups, cycloalkenyl groups, alkynyl groups, cycloalkynyl groups, aryl groups, heterocyclic groups, amino groups, alkoxy groups, aryloxy groups, heterocyclic oxy groups, Acyl group, alkoxycarbonyl group, aryloxycarbonyl group, acyloxy group, acylamino group, alkoxycarbonylamino group, aryloxycarbonylamino group, sulfonylamino group, sulfamoyl group, carbamoyl group, alkylthio group, arylthio group, heterocyclic thio group, Examples include a phosphoric acid amide group, a hydroxy group, a mercapto group, a halogen atom, a cyano group, a sulfo group, a carboxy group, a nitro group, and a silyl group. Moreover, when these substituents can further have one or more substituents, they may have the above-mentioned substituents as further substituents.
When R ¹ and R ² represent a substituent, the substituent is preferably an organic group, and the organic group may have a linear structure, a branched structure, or a cyclic structure. The organic group is more preferably an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an alkynyl group, a cycloalkynyl group, an aryl group, an alkoxy group, or a group formed by a combination of at least two of these. More preferably, it is a cycloalkyl group, an aryl group or an alkoxy group. The number of carbon atoms in the organic group is not particularly limited, but is preferably from 1 to 20, more preferably from 1 to 10. The above organic group may further have a substituent.
However, at least one of R ¹ and R ² represents a substituent. That is, there is no case where R ¹ and R ² both represent hydrogen atoms.

R ¹ and R ² may be combined to form a ring, and the ring is preferably an aliphatic hydrocarbon ring having 3 to 20 carbon atoms, and preferably an aliphatic hydrocarbon ring having 4 to 12 carbon atoms. It is more preferable that there be. The aliphatic hydrocarbon ring may have a substituent. In addition, the aliphatic hydrocarbon ring has -O-, -CO-, -COO-, -OCO-, -S-, -SO ₂ -, -NR- or these between the carbon-carbon bonds of the ring members. It may have a linking group formed by combining two or more. The above R represents a hydrogen atom or a substituent.

m represents 0 or 1, preferably 0.
n represents 0 or 1, preferably 1.

In general formula (1), *1 and *2 represent bonding positions. *1 and *2 include partial structures other than the group represented by the general formula (1) of the structural unit (a) (one atom such as a hydrogen atom, a fluorine-containing group, the main chain of the polymer (S), etc.) (an atomic group consisting of multiple atoms) bond together.

The structural unit (a) contains a fluorine-containing group and an acid-cleavable group, and more specific embodiments of the structural unit (a) include the following embodiments.
1) An embodiment in which a fluorine-containing group is bonded to *2 in general formula (1) directly or via a linking group 2) A fluorine-containing group is bonded to at least one of R ¹ and R ² in general formula (1) 3) An embodiment in which a fluorine-containing group is bonded to *1 in general formula (1) directly or via a linking group.

The linking groups in 1) and 3) above include -O-, -CO-, -COO-, -OCO-, -S-, -SO ₂ -, -NR-, or a combination of two or more of these. -O- or -S- is preferred. The above R represents a hydrogen atom or a substituent.

The structural unit (a) preferably has an acetal structure, a thioacetal structure, or a dithioacetal structure.
The acetal structure is preferably a structure represented by the following general formula (AC1) or (AC2).
The thioacetal structure is preferably a structure represented by the following general formula (SA1), (SA2) or (SA3).
The dithioacetal structure is preferably a structure represented by the following general formula (DS1) or (DS2).

In the general formulas (AC1), (SA1) and (DS1), R ¹ and R ² each independently represent a hydrogen atom or a substituent, and at least one of R ¹ and R ² represents a substituent. R ¹ and R ² may be combined to form a ring. At least one of R ¹ and R ² may be bonded to a moiety other than the structure represented by the general formula (AC1), (SA1) or (DS1) of the structural unit (a) to form a ring.
In the general formulas (AC2), (SA2), (SA3) and (DS2), R ³ represents a substituent, and k represents an integer of 0 to 3. When k represents 2 or 3, a plurality of R ³ 's may be the same or different.
In the general formulas (AC1), (AC2), (SA1), (SA2), (SA3), (DS1) and (DS2), * represents the bonding position.

In general formulas (AC1), (SA1) and (DS1), R ¹ and R ² each represent the same meaning as in general formula (1), and the specific examples and preferred ranges are also the same.
In general formulas (AC2), (SA2), (SA3) and (DS2), R ³ represents a substituent, and specific examples and preferred ranges include R ¹ and R ² in general formula (1) representing a substituent. These are the same as those listed as substituents when represented.
Preferably, k represents 0 or 1.

When the polymer (S) is a polymer synthesized by radical polymerization of a monomer having a (meth)acryloyl group such as a (meth)acrylic polymer or a (meth)acrylamide polymer, the structural unit (a) has the following general formula (A- A structural unit represented by any one of 1) to (A-5) is preferable.

In the above general formula, Ra ₁ represents a hydrogen atom or a methyl group. A represents -O- or -NH-. L ₁ represents a single bond or a divalent linking group. Q ₁ represents a group containing a fluorine atom. L ₂ represents a single bond or a divalent linking group. X ¹ , X ² , m, n, R ¹ and R ² each have the same meaning as in general formula (1). R ³ and k each represent the same meaning as in general formula (AC2).

In general formulas (A-1) to (A-4), A represents -O- or -NH-, preferably -O-.

In the general formulas (A-1) to (A-4), L ₁ represents a single bond or a divalent linking group. When L ₁ represents a divalent linking group, -O-, -CO-, -COO-, -S-, -SO ₂ -, -NR-, an organic linking group having 1 to 20 carbon atoms (for example, substituted (alkylene group which may have a substituent, cycloalkylene group which may have a substituent, arylene group which may have a substituent, etc.), or a linking group formed by combining two or more of these. . The above R represents a hydrogen atom or a substituent.
L ₁ is preferably a single bond, an alkylene group having 1 to 10 carbon atoms, -O-, -CO-, -COO-, -S-, or a linking group formed by combining two or more of these; More preferably, it is a bond, an alkylene group having 1 to 6 carbon atoms, -O-, -CO-, -COO-, -S-, or a linking group formed by a combination of two or more thereof.

In the general formulas (A-1) to (A-5), Q ₁ represents a group containing a fluorine atom. The group containing a fluorine atom is the same as described above.

In the general formulas (A-1) to (A-5), L ₂ represents a single bond or a divalent linking group. Specific examples and preferred ranges when L ₂ represents a divalent linking group are the same as those for the above case where L ₁ represents a divalent linking group.

In the above general formulas (A-1) to (A-5), X ¹ , X ² , m, n, R ¹ and R ² each have the same meaning as in general formula (1), specific examples and preferred The range is also the same. Moreover, R ³ and k each represent the same meaning as in general formula (AC2), and the specific examples and preferred ranges are also the same.

When the polymer (S) is polysilsesquioxane, the structural unit (a) is preferably a structural unit represented by any of the following general formulas (S-1) to (S-4).

In the above general formula, L ₁ represents a single bond or a divalent linking group. Q ₁ represents a group containing a fluorine atom. L ₂ represents a single bond or a divalent linking group. X ¹ , X ² , m, n, R ¹ and R ² each have the same meaning as in general formula (1). R ³ and k each represent the same meaning as in general formula (AC2).

In general formulas (S-1) to (S-4), “SiO _1.5 ” is a structural moiety (silsesquioxane unit).
Polysilsesquioxane is a network polymer or polyhedral cluster having siloxane constituent units derived from a hydrolyzable trifunctional silane compound, and can form a random structure, ladder structure, cage structure, etc. through siloxane bonds.
Hereinafter, "SiO _1.5 " described in this specification is also the same as above.

In the general formulas (S-1) to (S-4), L ₁ represents a single bond or a divalent linking group. Specific examples and preferred ranges of L ₁ are the same as L ₁ in general formulas (A-1) to (A-4).

In the general formulas (S-1) to (S-4), Q ₁ represents a group containing a fluorine atom. The group containing a fluorine atom is the same as described above.

In the general formulas (S-1) to (S-4), L ₂ represents a single bond or a divalent linking group. Specific examples and preferred ranges of L ₂ are the same as those for L ₁ above.

In the above general formulas (S-1) to (S-4), X ¹ , X ² , m, n, R ¹ and R ² each have the same meaning as in general formula (1), and specific examples and preferred The range is also the same. Moreover, R ³ and k each represent the same meaning as in general formula (AC2), and the specific examples and preferred ranges are also the same.

Specific examples of the structural unit (a) containing a fluorine atom-containing group and an acid-cleavable group are shown below, but the invention is not limited thereto. The following s and t each independently represent an integer of 0 to 10.

From the viewpoint of further improving the scratch resistance of the hard coat film, the content of the structural unit (a) in the polymer (S) is 3 mol% or more and 50% by mole or more based on the total structural units contained in the polymer (S). It is preferably less than mol%, more preferably 5 mol% or more and less than 40 mol%, even more preferably 7 mol% or more and less than 30 mol%, and 10 mol% or more and less than 20 mol%. is particularly preferable, and most preferably 10 mol% or more and less than 15 mol%.

[Structural unit (b) containing a cationically polymerizable group]
The polymer (S) has a structural unit (b) (also simply referred to as a "structural unit (b)") containing a cationically polymerizable group.
The cationically polymerizable group of the structural unit (b) is not particularly limited, and may be any known cationically polymerizable group. Examples of the cationically polymerizable group include an alicyclic ether group, a cyclic acetal group, a cyclic lactone group, a cyclic thioether group, a spiro-orthoester group, and a vinyloxy group.
The cationic polymerizable group is preferably an alicyclic ether group or a vinyloxy group, more preferably an epoxy group, an epoxycyclohexyl group, an oxetanyl group, or a vinyloxy group, even more preferably an epoxy group, an epoxycyclohexyl group, or an oxetanyl group, and an epoxy group or Epoxycyclohexyl group is most preferred. Note that each of the above groups may have a substituent.

The cationic polymerizable group is preferably a group represented by any of the following formulas (C1) to (C3).

In formulas (C1) to (C3), * represents the bonding position. In formula (C3), R _C represents a hydrogen atom or a substituent.

When R _C in formula (C3) represents a substituent, the substituent is not particularly limited, but is preferably an alkyl group, more preferably an alkyl group having 1 to 6 carbon atoms. Examples of the alkyl group having 1 to 6 carbon atoms include methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, n-hexyl group, and the like.
R _C preferably represents a hydrogen atom, a methyl group or an ethyl group, more preferably a methyl group or an ethyl group.

When the polymer (S) is a polymer synthesized by radical polymerization of a monomer having a (meth)acryloyl group such as a (meth)acrylic polymer or a (meth)acrylamide polymer, the structural unit (b) has the following general formula (CA- A structural unit represented by any one of 1) to (CA-3) is preferable.

In the general formulas (CA-1) to (CA-3), Ra ₁ represents a hydrogen atom or a methyl group. A represents -O- or -NH-. L ₃ represents a single bond or a divalent linking group. In the general formula (CA-3), R _C has the same meaning as in the above formula (C3).

In the general formulas (CA-1) to (CA-3), A represents -O- or -NH-, preferably -O-.

In the general formulas (CA-1) to (CA-3), L ₃ represents a single bond or a divalent linking group. Specific examples and preferred ranges of L ₃ are the same as L ₁ in the above general formulas (A-1) to (A-4).

In the general formula (CA-3), R _C has the same meaning as in the above formula (C3), and the specific examples and preferred ranges are also the same.

When the polymer (S) is polysilsesquioxane, the structural unit (b) is preferably a structural unit represented by any of the following general formulas (CS-1) to (CS-3).

In the general formulas (CS-1) to (CS-3), L ₃ represents a single bond or a divalent linking group. In the general formula (CS-3), R _C has the same meaning as in the above formula (C3).

In the general formulas (CS-1) to (CS-3), L ₃ represents a single bond or a divalent linking group. Specific examples and preferred ranges of L ₃ are the same as L ₁ in the above general formulas (A-1) to (A-4).

In the general formula (CS-3), R _C represents the same meaning as in the above formula (C3), and the specific examples and preferred ranges are also the same.

Specific examples of the structural unit (b) containing a cationically polymerizable group are shown below, but the invention is not limited thereto.

From the viewpoint of further improving the scratch resistance of the hard coat film, the content of the structural unit (b) in the polymer (S) is 15 mol% or more with respect to the total structural units contained in the polymer (S). It is preferably less than mol%, more preferably 20 mol% or more and less than 80 mol%, even more preferably 25 mol% or more and less than 70 mol%, and even more preferably 30 mol% or more and less than 60 mol%. is particularly preferred.

[Structural unit (c) containing a radically polymerizable group]
The polymer (S) has a structural unit (c) (also simply referred to as a "constituent unit (c)") containing a radically polymerizable group.
The radically polymerizable group of the structural unit (c) is not particularly limited, and may be any known radically polymerizable group. The radically polymerizable group is preferably a polymerizable unsaturated group. Examples of the polymerizable unsaturated group include a (meth)acryloyl group, a vinyl group, an allyl group, and a styryl group, with a (meth)acryloyl group being preferred. Note that each of the above groups may have a substituent.

When the polymer (S) is a polymer synthesized by radical polymerization of a monomer having a (meth)acryloyl group such as a (meth)acrylic polymer or a (meth)acrylamide polymer, the structural unit (c) has the following general formula (RA- A structural unit represented by 1) or (RA-2) is preferable.

In the general formulas (RA-1) and (RA-2), Ra ₁ represents a hydrogen atom or a methyl group. A represents -O- or -NH-. L ₄ represents a single bond or a divalent linking group. In the general formula (RA-1), Ra ₂ represents a hydrogen atom or a methyl group.

In the general formulas (RA-1) and (RA-2), A represents -O- or -NH-, preferably -O-.

In the general formulas (RA-1) and (RA-2), L ₄ represents a single bond or a divalent linking group. Specific examples and preferred ranges of L ₄ are the same as L ₁ in the above general formulas (A-1) to (A-4).

When the polymer (S) is polysilsesquioxane, the structural unit (c) is preferably a structural unit represented by the following general formula (RS-1) or (RS-2).

In the general formulas (RS-1) and (RS-2), L ₄ represents a single bond or a divalent linking group. In the general formula (RS-1), Ra ₂ represents a hydrogen atom or a methyl group.

In the general formulas (RS-1) and (RS-2), L ₄ represents a single bond or a divalent linking group. Specific examples and preferred ranges of L ₄ are the same as L ₁ in the above general formulas (A-1) to (A-4).

Specific examples of the structural unit (c) containing a radically polymerizable group are shown below, but the invention is not limited thereto.

From the viewpoint of further improving the scratch resistance of the hard coat film, the content of the structural unit (c) in the polymer (S) is 15 mol% or more with respect to the total structural units contained in the polymer (S). It is preferably less than mol%, more preferably 20 mol% or more and less than 80 mol%, even more preferably 25 mol% or more and less than 70 mol%, and even more preferably 30 mol% or more and less than 60 mol%. is particularly preferred.

In addition to the above structural units (a) to (c), the polymer (S) may have any other structural units.

When the polymer (S) is a polymer synthesized by radical polymerization such as a (meth)acrylic polymer or a (meth)acrylamide polymer, the weight average molecular weight (Mw) of the polymer (S) may be 8,000 or more and less than 80,000. It is preferably 10,000 or more and less than 70,000, and even more preferably 12,000 or more and less than 60,000.

When the polymer (S) is polysilsesquioxane, the weight average molecular weight (Mw) of the polymer (S) is preferably from 500 to 50,000, more preferably from 1,000 to 30,000, and from 1,500 to 12,000. It is even more preferable that there be.

The molecular weight dispersity (Mw/Mn) of the polymer (S) is, for example, 1.00 to 4.00, preferably 1.10 to 3.70, more preferably 1.20 to 3.00. , more preferably 1.20 to 2.50. Mw represents weight average molecular weight, and Mn represents number average molecular weight.

The weight average molecular weight and molecular weight dispersity of the polymer (S) are measured values by GPC (in terms of polystyrene) unless otherwise specified. Specifically, the weight average molecular weight was determined by preparing HLC-8220 (manufactured by Tosoh Corporation) as an apparatus, using tetrahydrofuran as an eluent, using TSKgel (registered trademark) G3000HXL + TSKgel (registered trademark) G2000HXL as a column, and at a temperature of 23°C. , using a differential refractive index (RI) detector under conditions of a flow rate of 1 mL/min.

Specific examples of the polymer (S) are shown below, but are not limited thereto.

<Production method of polymer (S)>
Polymer (S) can be produced by a known method.
When the polymer (S) is a polymer synthesized by radical polymerization such as a (meth)acrylic polymer or a (meth)acrylamide polymer, for example, a monomer containing a fluorine atom-containing group and an acid-cleavable group as described above, or a monomer as described above. It can be produced by mixing a monomer containing a cationically polymerizable group, a monomer containing the aforementioned radically polymerizable group, and any other monomer, and polymerizing the mixture in an organic solvent using a radical polymerization initiator. However, in order to prevent cleavage of the acid-cleavable group, it is preferable not to produce the polymer (S) under acidic conditions. Furthermore, during radical polymerization, it is preferable to protect the structural unit (c) by a known method in order to prevent the radically polymerizable group from reacting.

When the polymer (S) is polysilsesquioxane, it can be produced, for example, by a method of hydrolyzing and condensing a hydrolyzable silane compound. Examples of the above-mentioned hydrolyzable silane compounds include hydrolyzable trifunctional silane compounds containing the aforementioned fluorine atom-containing group and acid-cleavable group, hydrolyzable trifunctional silane compounds containing a cationically polymerizable group, and radically polymerizable groups. and any other hydrolyzable silane compounds can be used.
The hydrolysis and condensation reactions of the hydrolyzable silane compound can be carried out in the presence or absence of a solvent, and are preferably carried out in the presence of a solvent.
It is preferable that the hydrolysis and condensation reactions of the hydrolyzable silane compound proceed in the presence of a catalyst and water. However, in order to prevent cleavage of acid-cleavable groups, it is preferable not to produce the polymer (S) under acidic conditions, and therefore it is preferable not to use an acid catalyst.
The reaction temperature of the above hydrolysis and condensation reactions is not particularly limited, and is, for example, 40 to 100°C, preferably 45 to 80°C. Further, the reaction time of the above hydrolysis and condensation reactions is not particularly limited, and is, for example, 0.1 to 15 hours, preferably 1.5 to 10 hours. Moreover, the above-mentioned hydrolysis and condensation reactions can be performed under normal pressure, under increased pressure, or under reduced pressure. The atmosphere in which the above hydrolysis and condensation reactions are carried out may be, for example, in an inert gas atmosphere such as a nitrogen atmosphere or an argon atmosphere, or in the presence of oxygen such as air. Preferably in an atmosphere.

The content of the polymer (S) in the composition for forming a hard coat layer of the present invention is not particularly limited, but from the viewpoint of surface condition and scratch resistance, the content of the polymer (S) in the composition for forming a hard coat layer is based on the total solid content in the composition for forming a hard coat layer. It is preferably 0.001 to 5% by mass, more preferably 0.01 to 3% by mass, even more preferably 0.1 to 2% by mass, and even more preferably 0.1 to 1% by mass. It is particularly preferable that

In the composition for forming a hard coat layer of the present invention, only one type of polymer (S) may be used, or two or more types having different structures may be used in combination.

Hereinafter, other components that may be included in the composition for forming a hard coat layer of the present invention will be explained.

(Polyorganosilsesquioxane (a1) having a cationically polymerizable group)
The composition for forming a hard coat layer of the present invention preferably contains a polyorganosilsesquioxane (a1) having a cationically polymerizable group (also referred to as "polyorganosilsesquioxane (a1)").
The polyorganosilsesquioxane (a1) is a different component from the above-mentioned polymer (S).
The cationically polymerizable group in the polyorganosilsesquioxane (a1) is not particularly limited, and may be any known cationically polymerizable group. Examples of the cationically polymerizable group include an alicyclic ether group, a cyclic acetal group, a cyclic lactone group, a cyclic thioether group, a spiro-orthoester group, and a vinyloxy group.
The cationic polymerizable group is preferably an alicyclic ether group or a vinyloxy group, more preferably an epoxy group, an epoxycyclohexyl group, an oxetanyl group, or a vinyloxy group, even more preferably an epoxy group, an epoxycyclohexyl group, or an oxetanyl group, and an epoxy group or Epoxycyclohexyl group is most preferred. Note that each of the above groups may have a substituent.

The cationic polymerizable group is preferably a group represented by any of the following formulas (ca1) to (ca3).

In formulas (ca1) to (ca3), * represents the bonding position. In formula (ca3), R _ca represents a hydrogen atom or a substituent.

Specific examples and preferred ranges of the substituent when R _ca in formula (ca) represents a substituent are the same as those for the substituent when R _C in formula (C3) above represents a substituent.

The polyorganosilsesquioxane (a1) preferably has a structural unit represented by any of the following general formulas (csa-1) to (csa-3).

In the general formulas (csa-1) to (csa-3), L ₅ represents a single bond or a divalent linking group. In general formula (csa-3), R _ca has the same meaning as in formula (ca3).

In the general formulas (csa-1) to (csa-3), L ₅ represents a single bond or a divalent linking group. When L ₅ represents a divalent linking group, -O-, -CO-, -COO-, -S-, -SO ₂ -, -NR-, an organic linking group having 1 to 20 carbon atoms (for example, substituted (alkylene group which may have a substituent, cycloalkylene group which may have a substituent, arylene group which may have a substituent, etc.), or a linking group formed by combining two or more of these. . The above R represents a hydrogen atom or a substituent.
L ₅ is preferably a single bond, an alkylene group having 1 to 10 carbon atoms, -O-, -CO-, -COO-, -S-, or a linking group formed by combining two or more of these. More preferably, it is a bond, an alkylene group having 1 to 6 carbon atoms, -O-, -CO-, -COO-, -S-, or a linking group formed by a combination of two or more thereof.

In general formula (csa-3), R _ca represents the same meaning as in formula (ca3), and the specific examples and preferred ranges are also the same.

The content of the structural unit represented by any of the above-mentioned general formulas (csa-1) to (csa-3) in polyorganosilsesquioxane (a1) is as follows: It is preferably 50 mol% or more and 100 mol% or less, more preferably 70 mol% or more and 100 mol% or less, and preferably 90 mol% or more and 100 mol% or less, based on the total number of structural units contained. More preferred.

Polyorganosilsesquioxane (a1) may have any other constituent units in addition to the constituent units represented by any of the above general formulas (csa-1) to (csa-3). good.

The number average molecular weight (Mn) of the polyorganosilsesquioxane (a1) measured by gel permeation chromatography (GPC) in terms of standard polystyrene is preferably 500 to 6000, more preferably 1000 to 4500, even more preferably It is 1500-3000.

The molecular weight dispersity (Mw/Mn) of the polyorganosilsesquioxane (a1) in terms of standard polystyrene by GPC is, for example, 1.0 to 4.0, preferably 1.1 to 3.7, and more It is preferably 1.2 to 3.0, more preferably 1.3 to 2.5. Mw represents weight average molecular weight, and Mn represents number average molecular weight.

The method for measuring the weight average molecular weight and molecular weight dispersity of polyorganosilsesquioxane (a1) is the same as the method for measuring the weight average molecular weight and molecular weight dispersity of the polymer (S) described above.

One type of polyorganosilsesquioxane (a1) may be used, or two or more types having different structures may be used in combination.

The content of polyorganosilsesquioxane (a1) in the composition for forming a hard coat layer of the present invention is not particularly limited, but is 50% by mass or more based on the total solid content of the composition for forming a hard coat layer. It is preferably at least 70% by mass, more preferably at least 80% by mass. The upper limit of the content of polyorganosilsesquioxane (a1) in the composition for forming a hard coat layer is not particularly limited, but is preferably 99.999% by mass or less, and 99.99% by mass or less. is more preferable, and even more preferably 99.9% by mass or less.
Note that the total solid content refers to all components other than the solvent.

(Cationic polymerization initiator)
The composition for forming a hard coat layer of the present invention may contain a cationic polymerization initiator. In particular, when the above-mentioned polyorganosilsesquioxane (a1) is included in the composition for forming a hard coat layer, it is preferable that a cationic polymerization initiator is included.
In addition, since a cationic polymerization initiator is generally a compound that generates an acid by heat or light, as described below, polyorganosilsesquioxane (a1) is cured by cationic polymerization to form a hard coat layer. At this time, the acid-cleavable group of the structural unit (a) of the polymer (S) can be cleaved by the acid generated from the cationic polymerization initiator. Then, the fluorine atom-containing group can be separated from the polymer (S) by cleavage of the acid-cleavable group. As a result, the radical polymerization reaction when providing the scratch-resistant layer on the hard coat layer progresses efficiently, and the bond between the hard coat layer and the scratch-resistant layer is sufficiently formed. It is thought that the adhesion with the layer becomes high and excellent scratch resistance is obtained.

The cationic polymerization initiator may be a photocationic polymerization initiator or a thermal cationic polymerization initiator.
Examples of the cationic polymerization initiator include, but are not limited to, sulfonium salts, ammonium salts, iodonium salts (eg, diaryliodonium salts), triarylsulfonium salts, diazonium salts, and iminium salts. More specifically, for example, at least one cation selected from aromatic sulfonium, aromatic iodonium, aromatic diazonium, and pyridinium, and BF ₄ ⁻ , PF ₆ ⁻ , SbF ₆ ⁻ , AsF ₆ ⁻ , CF ₃ SO _Examples include cationic polymerization initiators such as onium salts and aluminum complexes, ^which are composed of at least one anion selected from 3-, (CF ₃ SO ₂ ) ₂ ^N- , and B(C ₆ F ₅ ) ₄ ^- .
Cationic polymerization initiators can be synthesized by known methods and are also available as commercial products. Commercially available products include, for example, CI-1370, CI-2064, CI-2397, CI-2624, CI-2639, CI-2734, CI-2758, CI-2823, CI-2855, and CI-5102 manufactured by Nippon Soda Co., Ltd. etc., PHOTOINITIATOR 2047 manufactured by Rhodia, UVI-6974, UVI-6990 manufactured by Union Carbide, CPI-10P, CPI-100P, CPI-101P, CPI-110P, TA-100, etc. manufactured by Sun-Apro, Sanshin Chemical Industry Co., Ltd. Examples include Sun-Aid SI-B2A and Sun-Aid SI-B3A manufactured by Manufacturer.

Specific commercial products of iodonium salt-based photocationic polymerization initiators include, for example, B2380 manufactured by Tokyo Kasei Co., Ltd., BBI-102 manufactured by Midori Kagaku Co., Ltd., WPI-113 manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., and manufactured by Fujifilm Wako Pure Chemical Industries, Ltd. Examples include WPI-124, WPI-169 manufactured by Fuji Film Wako Pure Chemical Industries, Ltd., WPI-170 manufactured by Fuji Film Wako Pure Chemical Industries, Ltd., and DTBPI-PFBS manufactured by Toyo Gosei Kagaku Co., Ltd.

One type of cationic polymerization initiator may be used, or two or more types having different structures may be used in combination.
The content of the cationic polymerization initiator in the composition for forming a hard coat layer is not particularly limited, but is, for example, 0.1 to 200 parts by mass per 100 parts by mass of polyorganosilsesquioxane (a1). parts by weight, and more preferably from 1 to 50 parts by weight.

(solvent)
The composition for forming a hard coat layer of the present invention may contain a solvent.
As the solvent, organic solvents are preferred, and one or more organic solvents can be used as a mixture in any proportion. Specific examples of organic solvents include alcohols such as methanol, ethanol, propanol, n-butanol, and i-butanol; ketones such as acetone, methyl isobutyl ketone, methyl ethyl ketone, and cyclohexanone; cellosolves such as ethyl cellosolve; toluene , aromatics such as xylene; glycol ethers such as propylene glycol monomethyl ether; acetate esters such as methyl acetate, ethyl acetate, and butyl acetate; diacetone alcohol, and the like.
The content of the solvent in the composition for forming a hard coat layer of the present invention can be appropriately adjusted within a range that can ensure the coating suitability of the composition for forming a hard coat layer. For example, the amount may be 50 to 500 parts by weight, preferably 80 to 200 parts by weight, based on 100 parts by weight of the total solid content of the composition for forming a hard coat layer.
The composition for forming a hard coat layer usually takes the form of a liquid.
The solid content concentration of the composition for forming a hard coat layer is usually 10 to 90% by mass, preferably 20 to 80% by mass, and particularly preferably 40 to 75% by mass.

The composition for forming a hard coat layer of the present invention may contain components other than those mentioned above, such as inorganic fine particles, dispersants, leveling agents, antifouling agents, antistatic agents, ultraviolet absorbers, and antioxidants. etc. may be contained.

The composition for forming a hard coat layer of the present invention can be prepared by mixing the various components described above simultaneously or sequentially in any order. The preparation method is not particularly limited, and a known stirrer or the like can be used for the preparation.

[Hard coat film]
The hard coat film of the present invention is a hard coat film including a base material (preferably a plastic base material) and a hard coat layer formed from the above-described composition for forming a hard coat layer of the present invention.

Although the details of the reason why a hard coat film with excellent surface condition and scratch resistance can be produced using the composition for forming a hard coat layer of the present invention are not clear, the present inventors have explained as follows. I'm guessing.
As an embodiment of the hard coat film having hardness and scratch resistance, a hard coat film having a base material, a hard coat layer, and a scratch resistant layer in this order is preferable. The hard coat layer is preferably a layer obtained by curing the composition for forming a hard coat layer containing the aforementioned polyorganosilsesquioxane (a1) having a cationically polymerizable group. The scratch-resistant layer is preferably a layer formed by curing a composition for forming a scratch-resistant layer containing a radically polymerizable compound (c1).
Here, on a hard coat layer containing a cured product of a composition for forming a hard coat layer containing polyorganosilsesquioxane (a1) having a cationically polymerizable group, a scratch-resistant layer containing a radically polymerizable compound (c1) is provided. When a cured product of the forming composition is formed, the hard coat layer is a cationic polymerization type, and the scratch-resistant layer is a radical polymerization type, so the polymerization systems of both layers are different.
When the hard coat film of the above embodiment is manufactured using a conventional composition as a composition for forming a hard coat layer, the adhesion between the hard coat layer and the scratch-resistant layer is weak because the polymerization systems of both layers are different. It is thought that the improvement in scratch resistance was not sufficient.
On the other hand, the composition for forming a hard coat layer of the present invention contains the above-mentioned polymer (S).
Since the polymer (S) has a structural unit (b) having a cationically polymerizable group, it can be bonded to polyorganosilsesquioxane (a1) having a cationically polymerizable group, which is a preferred component as a material for the hard coat layer, through a polymerization reaction. can do. Furthermore, since the polymer (S) has the structural unit (c) having a radically polymerizable group, it can be bonded to the radically polymerizable compound (c1), which is a preferred component as a material for the scratch-resistant layer, through a polymerization reaction.
Here, the polymer (S) is unevenly distributed on the hard coat layer surface (air interface side surface) when the hard coat layer forming composition is applied due to the action of the fluorine atom-containing group of the structural unit (a). Therefore, it is possible to efficiently improve the adhesion between layers.
In this way, the polymer (S) can bond with both the material of the hard coat layer and the material of the scratch-resistant layer, so it is possible to increase the adhesion between the layers and improve the scratch resistance. Conceivable. That is, the polymer (S) is considered to function as an interlayer adhesive.
In addition, particularly when hard coat films are continuously mass-produced using a continuous coater, orange peel-like irregularities are likely to occur on the surface of the hard coat layer. In order to improve the surface condition, generally, for example, a fluorine-containing surfactant is added to the hard coat layer forming composition to lower the surface tension of the hard coat layer forming composition. Conceivable. However, although the surface condition is improved when a fluorine-containing surfactant is used, the formation of a bond between the hard coat layer and the scratch-resistant layer due to the influence of the fluorine-containing surfactant unevenly distributed on the surface of the hard coat layer. It is thought that the adhesion is inhibited, the adhesion is reduced, and sufficient abrasion resistance cannot be obtained.
On the other hand, the structural unit (a) of the polymer (S) contains an acid-cleavable group in addition to the fluorine atom-containing group. The acid-cleavable group of structural unit (a) is cleaved by the acid generated from the cationic polymerization initiator when the composition for forming a hard coat layer is applied and cationic polymerization is performed. Since the fluorine atom-containing group is separated from the polymer (S) by cleavage of the acid-cleavable group, the subsequent radical polymerization reaction proceeds efficiently, and the bond between the hard coat layer and the scratch-resistant layer is sufficient. It is thought that this makes it possible to increase the adhesion between the hard coat layer and the scratch-resistant layer, resulting in excellent scratch resistance.

(Thickness of hard coat layer)
The thickness of the hard coat layer that can be formed using the composition for forming a hard coat layer of the present invention is not particularly limited, but is preferably 0.5 to 30 μm, more preferably 1 to 25 μm, More preferably, the thickness is 20 μm.
The thickness of the hard coat layer is calculated by observing the cross section of the laminate using an optical microscope. The cross-sectional sample can be created by a microtome method using an ultramicrotome cross-section cutting device, a cross-section processing method using a focused ion beam (FIB) device, or the like.

<Base material>
The composition for forming a hard coat layer of the present invention can be applied to a substrate and cured to form a hard coat layer.
The base material used for the hard coat film preferably has a transmittance in the visible light region of 70% or more, more preferably 80% or more, and even more preferably 90% or more.

(polymer)
The substrate is preferably a plastic substrate and preferably comprises a polymer.
As the polymer, a polymer having excellent optical transparency, mechanical strength, thermal stability, etc. is preferable.

Examples of the polymer include polycarbonate polymers, polyester polymers such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), and styrene polymers such as polystyrene and acrylonitrile-styrene copolymer (AS resin). In addition, polyolefins such as polyethylene and polypropylene, norbornene resins, polyolefin polymers such as ethylene-propylene copolymers, (meth)acrylic polymers such as polymethyl methacrylate, vinyl chloride polymers, amides such as nylon, and aromatic polyamides polymers, imide polymers, sulfone polymers, polyether sulfone polymers, polyetheretherketone polymers, polyphenylene sulfide polymers, vinylidene chloride polymers, vinyl alcohol polymers, vinyl butyral polymers, arylate polymers, polyoxy Examples include methylene polymers, epoxy polymers, cellulose polymers typified by triacetyl cellulose, copolymers of the above polymers, and polymers obtained by mixing the above polymers.

In particular, amide polymers and imide polymers such as aromatic polyamides have a large number of breaks and bends measured using an MIT tester according to JIS (Japanese Industrial Standards) P8115 (2001), and have relatively high hardness, so they are suitable as base materials. It can be preferably used. For example, aromatic polyamides such as those described in Example 1 of Japanese Patent No. 5699454, polyimides described in Japanese translations of PCT publication No. 2015-508345, PCT publication No. 2016-521216, and WO2017/014287 are preferably used as the base material. Can be used.
As the amide polymer, aromatic polyamide (aramid polymer) is preferable.
The base material preferably contains at least one polymer selected from imide polymers and aramid polymers.

(Thickness of base material)
The base material is preferably in the form of a film.
The thickness of the base material is more preferably 100 μm or less, even more preferably 80 μm or less, and most preferably 50 μm or less. Further, from the viewpoint of ease of handling the base material, the thickness of the base material is preferably 3 μm or more, more preferably 5 μm or more, and most preferably 15 μm or more.

<Abrasion resistant layer>
It is preferable that the hard coat film of the present invention has a base material, a hard coat layer, and an abrasion resistant layer in this order.
The scratch-resistant layer is not particularly limited, but is preferably a layer formed by curing a composition for forming a scratch-resistant layer containing a radically polymerizable compound (c1).

(Radical polymerizable compound (c1))
The radically polymerizable compound (c1) (also referred to as "compound (c1)") will be explained.
Compound (c1) is a compound having a radically polymerizable group.
The radically polymerizable group in compound (c1) is not particularly limited, and generally known radically polymerizable groups can be used. Examples of the radically polymerizable group include polymerizable unsaturated groups, specifically, (meth)acryloyl groups, vinyl groups, allyl groups, etc., with (meth)acryloyl groups being preferred. Note that each of the above groups may have a substituent.
Compound (c1) is preferably a compound having two or more (meth)acryloyl groups in one molecule, more preferably a compound having three or more (meth)acryloyl groups in one molecule. .
The molecular weight of the compound (c1) is not particularly limited, and it may be a monomer, an oligomer, or a polymer.

Only one type of compound (c1) may be used, or two or more types having different structures may be used in combination.

The content of the compound (c1) in the composition for forming a scratch-resistant layer is preferably 80% by mass or more, more preferably 85% by mass or more, based on the total solid content in the composition for forming a scratch-resistant layer. It is preferably 90% by mass or more, and more preferably 90% by mass or more.

(radical polymerization initiator)
It is preferable that the composition for forming a scratch-resistant layer contains a radical polymerization initiator.
One type of radical polymerization initiator may be used, or two or more types having different structures may be used in combination. Further, the radical polymerization initiator may be a photopolymerization initiator or a thermal polymerization initiator.
The content of the radical polymerization initiator in the composition for forming a scratch-resistant layer is not particularly limited, but is preferably 0.1 to 200 parts by mass, for example, per 100 parts by mass of compound (c1). ~50 parts by mass is more preferred.

(solvent)
The scratch-resistant layer forming composition may contain a solvent.
The solvent is the same as the solvent that may be included in the above-mentioned composition for forming a hard coat layer.
The content of the solvent in the composition for forming a scratch-resistant layer in the present invention can be adjusted as appropriate within a range that can ensure the coating suitability of the composition for forming a scratch-resistant layer. For example, the amount may be 50 to 500 parts by weight, preferably 80 to 200 parts by weight, based on 100 parts by weight of the total solid content of the composition for forming a scratch-resistant layer.
The composition for forming a scratch-resistant layer usually takes the form of a liquid.
The solid content concentration of the scratch-resistant layer forming composition is usually 10 to 90% by weight, preferably 15 to 80% by weight, and particularly preferably 20 to 70% by weight.

(Other additives)
The composition for forming a scratch-resistant layer may contain components other than those mentioned above, such as inorganic particles, a leveling agent, an antifouling agent, an antistatic agent, a slip agent, and a solvent.

(Thickness of scratch-resistant layer)
The thickness of the scratch-resistant layer is preferably less than 3.0 μm, more preferably 0.1 to 2.0 μm, and preferably 0.1 to 1.0 μm from the viewpoint of repeated bending resistance. More preferred.

<Production method of hard coat film>
The method for manufacturing the hard coat film of the present invention will be explained.
The method for producing a hard coat film of the present invention is a method for producing a hard coat film comprising a base material and a hard coat layer, which comprises applying the composition for forming a hard coat layer of the present invention onto the base material. Preferably, the method for producing a hard coat film comprises forming the hard coat layer by forming a film and subjecting the coating film to a curing treatment.

The above base material is as described above.

The curing treatment is preferably a curing treatment using at least one of light and heat, and more preferably a curing treatment using light and heat because the curing reaction rate can be increased. The photocuring treatment is a treatment in which a polymerization reaction is advanced by irradiation with light (preferably ionizing radiation). Thermal curing treatment is a treatment in which a polymerization reaction is advanced by heating.

A preferred embodiment of the method for producing a hard coat film of the present invention includes a production method including the following steps (I) to (IV).
(I) A composition for forming a hard coat layer containing the above-mentioned polymer (S), the above-mentioned polyorganosilsesquioxane (a1), and a cationic polymerization initiator is applied onto the base material to form a hard coat layer coating. (II) A step of forming a hard coat layer by subjecting the hard coat layer coating to a curing treatment. (III) A step of forming a radically polymerizable compound (c1) and a radical polymerization initiator on the hard coat layer. (IV) Step of forming a scratch-resistant layer by applying a hardening treatment to the scratch-resistant layer coating.

-Step (I)-
The method for applying the composition for forming a hard coat layer in step (I) is not particularly limited, and any known method can be used. Examples include dip coating, air knife coating, curtain coating, roller coating, wire bar coating, gravure coating, die coating, and the like.

-Step (II)-
In step (II), performing a curing treatment on the hard coat layer coating film means that at least a portion of the cationic polymerizable groups of the polyorganosilsesquioxane (a1) and the polymer (S) contained in the hard coat layer coating film are cured. It means to cause a polymerization reaction.
The hard coat layer coating film is cured by cationic polymerization, and preferably by at least one of light and heat.

The type of light (preferably ionizing radiation) is not particularly limited, and examples include X-rays, electron beams, ultraviolet rays, visible light, and infrared rays, with ultraviolet rays being preferably used. For example, if the hard coat layer coating is UV curable, it is preferable to semi-cure the curable compound by irradiating it with UV rays at a dosage of 10 mJ/cm ² to 2000 mJ/cm ² using an UV lamp. It is more preferably 50 mJ/cm ² to 1800 mJ/cm ² , even more preferably 100 mJ/cm ² to 1500 mJ/cm ² . As the type of ultraviolet lamp, a metal halide lamp, a high pressure mercury lamp, etc. are preferably used.

When curing by heat, there is no particular restriction on the temperature reached by heating the hard coat layer coating, but it is preferably 80°C or more and 200°C or less, more preferably 100°C or more and 180°C or less. Preferably, the temperature is 120°C or more and 160°C or less.

The oxygen concentration during curing is preferably 0 to 1.0% by volume, more preferably 0 to 0.1% by volume, and most preferably 0 to 0.05% by volume.

-Step (III)-
The method for applying the composition for forming a scratch-resistant layer in step (III) is not particularly limited, and any known method can be used. Examples include dip coating, air knife coating, curtain coating, roller coating, wire bar coating, gravure coating, die coating, and the like.

-Process (IV)-
The curing of the scratch-resistant coating film in step (IV) is performed by radical polymerization, and is preferably performed by at least one of light and heat. Light irradiation and heating are the same as those described in step (II). Note that curing the scratch-resistant layer coating film refers to subjecting at least a portion of the radically polymerizable groups of the radically polymerizable compound (c1) contained in the scratch-resistant layer coating film to a polymerization reaction.

In the present invention, it is preferable to semi-cure the hard coat layer coating in the step (II). That is, in step (II), the hard coat layer coating film is semi-cured, and then, in step (III), a scratch-resistant layer forming composition is applied on the semi-cured hard coat layer to form the scratch-resistant layer coating film. is formed, and then, in step (IV), it is preferable to cure the scratch-resistant layer coating and to completely cure the hard coat layer. Here, semi-curing the hard coat layer coating film means that only a part of the cationic polymerizable groups of the polyorganosilsesquioxane (a1) and the polymer (S) contained in the hard coat layer coating film are subjected to a polymerization reaction. It means to cause. Semi-curing of the hard coat layer coating can be performed by adjusting the amount of light irradiation and the heating temperature and time.

Drying treatment as necessary between step (I) and step (II), between step (II) and step (III), between step (III) and step (IV), or after step (IV) You may do so. Drying treatment is performed by blowing warm air, placing in a heating furnace, transporting in a heating furnace, heating with a roller from the side (base material side) where the hard coat layer and scratch-resistant layer are not provided, etc. be able to. The heating temperature is not particularly limited as long as it is set to a temperature that allows the solvent to be removed by drying. Here, the heating temperature refers to the temperature of hot air or the ambient temperature in the heating furnace.

The hard coat film of the present invention has excellent surface shape and scratch resistance, and can be used, for example, as an optical film. Further, the hard coat film of the present invention can be used as a surface protection film of an image display device.

The present invention also relates to an article equipped with the hard coat film of the present invention and an image display device equipped with the hard coat film of the present invention as a surface protection film.

EXAMPLES Hereinafter, the present invention will be explained in more detail with reference to Examples, but the scope of the present invention should not be construed as being limited thereby.

<Synthesis of monomer 1>
In a 100 mL eggplant flask, 5.0 g of 1,1-dimethoxycyclohexane, 9.0 g of 2-hydroxy methacrylate, 25.0 g of 1H,1H,2H,2H-perfluorooctanol, 0.87 g of pyridinium p-toluenesulfonate, and 30 mL of toluene. was weighed out, stirred at 40°C for 1 hour, and then stirred at 40°C for 4 hours under reduced pressure of 100 mmHg. After cooling the resulting reaction solution to room temperature (23° C.), it is separated and washed with saturated sodium bicarbonate water, and the resulting organic layer is dried over anhydrous magnesium sulfate, concentrated, and subjected to silica gel column chromatography. As a result, 8.0 g of monomer 1 represented by the following formula was obtained as a colorless liquid (yield: 40%).

<Synthesis of monomer 2>
100 g of 2-hydroxyethyl methacrylate and 240 mL of N,N-dimethylacetamide (DMAc) were added to a 2000 mL three-necked flask equipped with a stirring blade, a thermometer, and a dropping funnel, and the mixture was cooled in an ice bath. Next, 126.8 g of 3-chloropropionyl chloride was added dropwise, and the mixture was stirred for 3 hours under ice cooling. After cooling the resulting reaction solution to room temperature, 1000 mL of ethyl acetate was added, and the mixture was separated and washed with 1 mol/L hydrochloric acid, a saturated aqueous sodium bicarbonate solution, and water, and the resulting organic layer was dried over anhydrous magnesium sulfate. By concentrating, 85 g of the target monomer 2 was obtained as a pale yellow liquid (yield: 88%).

<Synthesis of polymer (SX1-1)>
2.34 g of monomer 1, 3.60 g of Cyclomer M100 (manufactured by Daicel Corporation), 4.05 g of monomer 2, 18.57 g of methyl ethyl ketone (MEK), dimethyl 2,2'-azobis(isobutyrate) (polymerized 3.760 g of an initiator (manufactured by Fuji Film Wako Pure Chemical Industries, Ltd.) was weighed out and stirred at 70° C. for 6 hours.
After the reaction, reprecipitation was performed using 500 mL of methanol. The obtained solid was dissolved in 15 g of MEK, and after adding 5.57 g of triethylamine and 0.01 g of p-methoxyphenol, the mixture was stirred at 60° C. for 4 hours. After the reaction solution was returned to room temperature, it was reprecipitated using 500 mL of methanol and dissolved in 25 g of MEK to obtain 5.1 g of polymer (SX1-1) (yield 53%).
In the reaction formula below, "M100" represents cyclomer M100. Further, the unit of content (content ratio) of each structural unit in the polymer is "mol%".

Polymers (SX1-2), (SX1-3), (SX1-4), (SX1-5), (SX2-1), (SX3-1) and (SX4-1) are polymers (SX1-1) They were synthesized by a synthesis method similar to that of , respectively, by changing the type and amount of monomers and the amount of polymerization initiator.

<Synthesis of monomer 3>
Using (3-mercaptopropyl)trimethoxysilane and 2-(perfluorohexyl)ethyl vinyl ether (CHEMINOX FAVE-6 (Unimatec)), monomer 3 was prepared according to the method described in Tetrahedron, 1991, 47, 4927-4940. was synthesized. In the following structural formula, Et represents an ethyl group.

<Synthesis of polymer (SX5-1)>
3.90 g of Monomer 3, 6.59 g of 3-glycidoxypropyltrimethoxysilane (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), and 6.59 g of 3-methacryloxypropyltrimethoxysilane (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) 6.93 g, 50 g of acetone, 1.38 g of 5% aqueous potassium carbonate solution, and 9.0 g of pure water were weighed out and stirred at 50° C. for 5 hours. The resulting reaction solution was cooled to room temperature, 50 g of methyl isobutyl ketone (MIBK) and 50 g of 5% brine were added, and the organic layer was extracted. The organic layer was further washed once with 50 g of 5% saline and twice with 50 g of pure water, and then 10 g of magnesium sulfate and 0.01 g of p-methoxyphenol were added. After filtering off the magnesium sulfate, the solvent was distilled off under reduced pressure at 50° C. and 35 mmHg to obtain 20.2 g of polymer (SX5-1) as a 60.5% by mass MIBK solution (yield 95%).
In the following structural formula, Me represents a methyl group and Et represents an ethyl group. Further, the unit of content (content ratio) of each structural unit in the polymer is "mol%".

The structural formula and weight average molecular weight (Mw) of each polymer are shown below. The unit of content (content ratio) of each structural unit in the following structural formula is "mol%". “SiO _1.5 ” represents a silsesquioxane unit.

A hard coat film having a base material, a hard coat layer and an abrasion resistant layer was produced using the above polymer as an interlayer adhesive.

The following (R-1) was synthesized as a polymer used in comparative examples. (R-1) corresponds to the polymer (P-7) of Patent Document 1 (International Publication No. 2016/039327).

Further, Compound (II) described in [0062] to [0063] of Patent Document 2 (Japanese Unexamined Patent Publication No. 2011-241190) was used in a comparative example.

<Preparation of base material>
(Production of polyimide powder)
After adding 832 g of N,N-dimethylacetamide (DMAc) to a 1 L reactor equipped with a stirrer, nitrogen injector, dropping funnel, temperature controller, and condenser under a nitrogen stream, the temperature of the reactor was lowered to 25°C. It was set to ℃. To this, 64.046 g (0.2 mol) of bistrifluoromethylbenzidine (TFDB) was added and dissolved. While maintaining the resulting solution at 25°C, 31.09 g (0.07 mol) of 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride (6FDA) and biphenyltetracarboxylic dianhydride were added. 8.83 g (0.03 mol) of BPDA was added thereto, and the mixture was stirred for a certain period of time to react. Thereafter, 20.302 g (0.1 mol) of terephthaloyl chloride (TPC) was added to obtain a polyamic acid solution with a solid content concentration of 13% by mass. Next, 25.6 g of pyridine and 33.1 g of acetic anhydride were added to this polyamic acid solution, stirred for 30 minutes, further stirred at 70° C. for 1 hour, and then cooled to room temperature. 20 L of methanol was added thereto, and the precipitated solid content was filtered and pulverized. Thereafter, it was dried in vacuum at 100° C. for 6 hours to obtain 111 g of polyimide powder.

(Preparation of base material S-1)
100 g of the above polyimide powder was dissolved in 670 g of N,N-dimethylacetamide (DMAc) to obtain a 13% by mass solution. The obtained solution was cast onto a stainless steel plate and dried with hot air at 130°C for 30 minutes. After that, the film was peeled off from the stainless steel plate and fixed to the frame with pins, and the frame with the film fixed was placed in a vacuum oven and heated for 2 hours while gradually increasing the heating temperature from 100°C to 300°C. It was cooled to After the cooled film was separated from the frame, it was further heat treated at 300° C. for 30 minutes as a final heat treatment step to obtain a 30 μm thick base material S-1 made of polyimide film.

<Synthesis of polyorganosilsesquioxane (a1)>
(Synthesis of compound (A))
In a 1000 ml flask (reaction vessel) equipped with a thermometer, stirrer, reflux condenser, and nitrogen inlet tube, 300 mmol (73. 9 g), 7.39 g of triethylamine, and 370 g of MIBK (methyl isobutyl ketone) were mixed, and 73.9 g of pure water was added dropwise over 30 minutes using a dropping funnel. This reaction solution was heated to 80° C., and the polycondensation reaction was carried out under a nitrogen stream for 10 hours.
Thereafter, the reaction solution was cooled, 300 g of 5% by mass saline was added, and the organic layer was extracted. The organic layer was sequentially washed twice with 300 g of 5 mass% saline and 300 g of pure water, and then concentrated under conditions of 1 mmHg and 50°C to produce a colorless and transparent liquid MIBK solution with a solid content concentration of 59.8 mass%. 87.0 g of compound (A) represented by the following structural formula was obtained.
The number average molecular weight (Mn) of compound (A) was 2050, and the molecular weight dispersity was 1.9.

[Example 1]
<Preparation of composition for forming hard coat layer>
(Hard coat layer forming composition HC-1)
Compound (SX1-1), CPI-100P, and MIBK (methyl isobutyl ketone) as interlayer adhesives were added to the MIBK solution containing the above compound (A), and the content of each component was adjusted as follows. The mixture was poured into a mixing tank and stirred. The obtained composition was filtered through a polypropylene filter with a pore size of 0.45 μm to obtain a hard coat layer forming composition HC-1.

Compound (A) 164.38 parts by mass Interlayer adhesive (SX1-1) 0.38 parts by mass CPI-100P 6.0 parts by mass MIBK 67.70 parts by mass

Note that CPI-100P is a photocationic polymerization initiator (solid content concentration 50% by mass) manufactured by San-Apro Co., Ltd.

<Preparation of composition for forming a scratch-resistant layer>
(Scratch resistant layer forming composition SR-1)
Each component with the composition described below was put into a mixing tank, stirred, and filtered through a polypropylene filter with a pore size of 0.4 μm to obtain a scratch-resistant layer forming composition SR-1.
DPHA 96.2 parts by mass Irgacure 127 2.8 parts by mass RS-90 1.0 parts by mass Methyl ethyl ketone 300.0 parts by mass

The compounds used in the composition for forming a scratch-resistant layer are as follows.
DPHA: mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate, manufactured by Nippon Kayaku Co., Ltd. Irgacure 127 (Irg.127): photoradical polymerization initiator, manufactured by BASF Corporation RS-90: slip agent, DIC Corporation ) made

(Manufacture of hard coat film)
The hard coat layer forming composition HC-1 was applied onto the polyimide base material S-1 with a thickness of 30 μm using a wire bar #18 so that the film thickness after curing would be 18 μm, and then A hard coat layer was applied to the surface.
Next, the hard coat layer coating film was dried at 120° C. for 1 minute, and then irradiated with an air-cooled mercury lamp at 25° C. and an oxygen concentration of 100 ppm (parts per million), with an illumination intensity of 18 mW/cm ² and an irradiation amount of 19 mJ/cm. ² ultraviolet rays were irradiated. In this way, the hard coat layer coating film was semi-cured.
Thereafter, a scratch-resistant layer forming composition SR-1 was applied onto the semi-cured hard coat layer coating using a die coater so that the film thickness after curing was 0.8 μm.
Next, the obtained laminate was dried at 120°C for 1 minute, and then irradiated with ultraviolet rays at 25°C, oxygen concentration 100ppm, illumination intensity 60mW/cm ² and irradiation amount 600mJ/cm ² , and further dried at 80°C and oxygen concentration 100ppm. The hard coat layer coating film and the scratch-resistant layer coating film were completely cured by irradiating ultraviolet rays at an illuminance of 60 mW/cm ² and an irradiation amount of 600 mJ/cm ² using an air-cooled mercury lamp under the following conditions.
Thereafter, the obtained laminate was heat-treated at 120° C. for 1 hour to obtain a hard coat film having a hard coat layer and an abrasion resistant layer in this order on the base material.

[Examples 2 to 9, Comparative Examples 1 to 2]
Hard coat films were produced in the same manner as in Example 1, except that the type of interlayer adhesive used was changed as shown in Table 1 below.

(Evaluation of scratch resistance)
The surface of the scratch-resistant layer of the manufactured hard coat film of each Example and Comparative Example was subjected to a rubbing test under the following conditions using a rubbing tester, and was used as an index of scratch resistance.
Evaluation environmental conditions: 25℃, relative humidity 60%
Rubbing material: Steel wool (manufactured by Nippon Steel Wool Co., Ltd., grade No. #0000)
Wrap it around the scraping tip (1cm x 1cm) of the tester that comes into contact with the sample and fix the band. Travel distance (one way): 13cm
Rubbing speed: 13cm/sec Load: 500g/ ^cm2
Tip contact area: 1cm x 1cm
Number of times of rubbing: 10 times back and forth, 100 times back and forth, 500 times back and forth, 1000 times both ways Ink was applied, visual observation was made using reflected light, and the number of times of rubbing was measured when scratches occurred on the part that had been in contact with the steel wool for evaluation.
S: No scratches occur when rubbed 1000 times back and forth A: No scratches occur when rubbed 500 times back and forth, but scratches occur when rubbed 1000 times back and forth B: Scratches occur when rubbed 100 times back and forth No, but a scratch will occur if you rub it back and forth 500 times. C: No scratch will occur if you rub it back and forth 10 times, but a scratch will occur if you rub it back and forth 100 times. D: A scratch will occur if you rub it back and forth 10 times.

(Evaluation of surface condition)
A black polyethylene terephthalate film for preventing reflection was pasted on the surface of the hard coat film of each of the produced Examples and Comparative Examples opposite to the surface having the hard coat layer and the scratch-resistant layer (coating side). A sample was prepared. A three-wavelength fluorescent lamp (FL20SS/EX-N/18 (Matsushita Electric Industrial Co., Ltd.) was illuminated from the front (perpendicular to the surface) and diagonally of the coated side of the prepared sample in a room with all black surroundings, blocking external light. The coated side was visually observed using a desk lamp (manufactured by J.D. Co., Ltd.) and evaluated according to the following evaluation criteria.
A: Even if you look carefully, you can't see any unevenness including the yuzu-skin-like unevenness.
B: If you look carefully, you can see some orange skin-like unevenness with a gentle period, but it is not noticeable.
C: It is visually recognized that citrus skin-like unevenness exists in less than 1/3 of the surface area.
D: It is visually recognized that the irregularities in the shape of an orange skin are present in 1/3 or more of the surface area, or the irregularities with a larger difference in height than the irregularities in the shape of an orange skin are present at a glance.

The results are shown in Table 1 below.

As shown in Table 1, the hard coat films of Examples 1 to 9 were excellent in surface condition and scratch resistance.

According to the present invention, a hard coat layer forming composition capable of forming a hard coat film having excellent surface condition and scratch resistance, and a hard coat formed using the above hard coat layer forming composition. A film, a method for producing the hard coat film, and an article containing the hard coat film can be provided.

Although the invention has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention.
This application is based on a Japanese patent application (Japanese Patent Application No. 2020-111730) filed on June 29, 2020, the contents of which are incorporated herein by reference.

Claims (14)

A polymer (S ) A composition for forming a hard coat layer. The composition for forming a hard coat layer according to claim 1, wherein the acid-cleavable group includes a group represented by the following general formula (1).

In general formula (1),
X ¹ and X ² each independently represent an oxygen atom or a sulfur atom.
R ¹ and R ² each independently represent a hydrogen atom or a substituent, and at least one of R ¹ and R ² represents a substituent. R ¹ and R ² may be combined to form a ring. At least one of R ¹ and R ² may be bonded to a moiety other than the group represented by general formula (1) of the structural unit (a) to form a ring.
m and n each independently represent 0 or 1. However, when R ¹ or R ² represents a hydrogen atom, n represents 1.
*1 and *2 represent bonding positions. The composition for forming a hard coat layer according to claim 1 or 2, wherein the structural unit (a) has an acetal structure, a thioacetal structure, or a dithioacetal structure. The acetal structure is a structure represented by the following general formula (AC1) or (AC2), the thioacetal structure is a structure represented by the following general formula (SA1), (SA2) or (SA3), and the The composition for forming a hard coat layer according to claim 3, wherein the dithioacetal structure is represented by the following general formula (DS1) or (DS2).

In the general formulas (AC1), (SA1) and (DS1), R ¹ and R ² each independently represent a hydrogen atom or a substituent, and at least one of R ¹ and R ² represents a substituent. R ¹ and R ² may be combined to form a ring. At least one of R ¹ and R ² may be bonded to a moiety other than the structure represented by the general formula (AC1), (SA1) or (DS1) of the structural unit (a) to form a ring.
In the general formulas (AC2), (SA2), (SA3) and (DS2), R ³ represents a substituent, and k represents an integer of 0 to 3. When k represents 2 or 3, a plurality of R ³ 's may be the same or different.
In the general formulas (AC1), (AC2), (SA1), (SA2), (SA3), (DS1) and (DS2), * represents the bonding position. The composition for forming a hard coat layer according to any one of claims 1 to 4, wherein the number of fluorine atoms contained in the fluorine atom-containing group is 3 or more and 17 or less. Claims 1 to 5, wherein the content of the structural unit (a) in the polymer (S) is 3 mol% or more and less than 50 mol% of the total structural units contained in the polymer (S). The composition for forming a hard coat layer according to any one of the items. The composition for forming a hard coat layer according to any one of claims 1 to 6, wherein the polymer (S) is a (meth)acrylic polymer or a polysilsesquioxane. The hard coat layer according to any one of claims 1 to 7, wherein the cationic polymerizable group of the structural unit (b) is a group represented by any of the following general formulas (C1) to (C3). Forming composition.

In general formulas (C1) to (C3), * represents a bonding position. In general formula (C3), R _C represents a hydrogen atom or a substituent. The composition for forming a hard coat layer according to any one of claims 1 to 8, wherein the radically polymerizable group of the structural unit (c) is a (meth)acryloyl group. A hard coat film comprising a plastic base material and a hard coat layer formed from the composition for forming a hard coat layer according to any one of claims 1 to 9. A method for producing a hard coat film comprising a base material and a hard coat layer, the method comprising: applying the composition for forming a hard coat layer according to any one of claims 1 to 9 onto the base material to form a coating film; A method for producing a hard coat film, comprising forming the hard coat layer by forming a hard coat layer and subjecting the coating film to a curing treatment. The method for producing a hard coat film according to claim 11, wherein the curing treatment is a curing treatment using light and heat. An article comprising the hard coat film according to claim 10. The article according to claim 13, comprising the hard coat film as a surface protection film.