JP2020090617A - Photosetting composition - Google Patents

Abstract

To provide a photosetting composition capable of adding extremely high scratch resistance and excellent transparency to a surface of a plastic substrate or the like, and a laminate having a cured article thereof.SOLUTION: There is provided a photosetting composition containing (A) a polyfunctional polymerizable monomer having a high quality diamond-like nucleus having a (meth)acryl group, (B) a hydroxyl group-containing (meth)acrylic monofunctional polymerizable monomer having at least one hydroxyl group, and having a (meth)acryl group in a molecule, and an epoxy group-containing (meth)acrylic monofunctional polymerizable monomer having at least one epoxy group and a (meth)acrylic group, and a polyfunctional (meth)acrylic polymerizable monomer represented by the following formula (3), wherein Ris a 3 to 6-valent organic residue, Rand Rare each independently a hydrogen atom or a methyl group, c is an integer of 0 to 3, and d is an integer of 3 to 6, and (C) a photoinitiator.SELECTED DRAWING: None

Description

The present invention relates to a photocurable composition capable of imparting extremely high scratch resistance and excellent transparency to the surface of a plastic substrate or the like. Furthermore, the present invention relates to a laminated body in which a cured body (cured film) of the composition is laminated.

Plastic has various characteristics such as light weight, easy workability, and impact resistance, and is used as a substitute for glass for various applications such as eyeglass lenses. Plastic has the advantages of being lighter in weight than glass and being excellent in impact resistance and molding processability, but on the other hand, it has a drawback that the surface has low scratch resistance and is easily damaged by contact, friction, scratching or the like. Therefore, in order to improve scratch resistance, a method of laminating a cured film for protecting the plastic surface on the plastic surface has been proposed. Further, due to the effects on the human body, influences, and the environment, there is an increasing demand for photocurable compositions having a reduced amount of solvent, preferably solventless. Among them, in particular, it is desired to develop a low-viscosity photocurable composition capable of laminating thin films and exhibiting high scratch resistance.

Therefore, the applicant of the present invention, in a solventless photocurable composition, has excellent storage stability, high scratch resistance, and excellent adhesion to a polycarbonate optical substrate, a polyurethane optical substrate, and the like. A developing composition has been proposed (see Patent Document 1).

However, in the photocurable composition described in Patent Document 1, the adhesiveness may decrease depending on the type of the optical base material to be laminated. Therefore, the photocurable composition regardless of the type of the optical base material to be laminated. Moreover, since the viscosity of the photocurable composition is not sufficiently low, a photocurable composition having an even lower viscosity has been desired.

Therefore, the applicant of the present invention provides a low-viscosity photocurable composition using a specific polyfunctional polymerizable monomer, an N-vinyl compound, and a specific monofunctional polymerizable monomer having an epoxy group or a hydroxyl group. Therefore, a composition having high adhesion to various optical substrates and high scratch resistance is proposed (see Patent Document 2).

International publication WO2017/082432 Japanese Patent Application No. 2017-230889 JP, 2012-035537, A Journal of Applied Polymer Science, Vol. 114, 2109-2115 (2009)

On the other hand, in recent years, due to the demand for higher functionality, development of a photocurable composition having higher scratch resistance is desired.

Further, for the purpose of improving scratch resistance, a composition containing fine powder of high hardness such as diamond is being studied (see Patent Document 3).

However, in the composition containing the high hardness fine powder, it is difficult to obtain uniform scratch resistance because the high hardness fine powder, which is a component that is incompatible with the base material component, is dispersed. There is a problem that transparency is impaired due to the difference in refractive index between the inorganic and/or organic material serving as the base material.

Therefore, an object of the present invention is to provide a photocurable composition that gives a cured product (cured film) having very high scratch resistance and excellent transparency while being a solvent-free system. It is in. Another object of the present invention is to provide a laminate in which a cured product (cured film) of the photocurable composition is laminated on a plastic substrate.

The present inventors have conducted extensive studies to solve the above problems. As a result, the photocurable composition containing the specific polyfunctional polymerizable monomer and the specific (meth)acrylic polymerizable monomer has very high scratch resistance and excellent transparency. It was found that the composition has a property.

That is, the present invention is
It is a photocurable composition containing the following (A) component, (B) component, and (C) component.
(A) a polyfunctional polymerizable monomer represented by the following formula (1),
Rn-D (1)
(R is an acrylic or methacrylic group, n is 2 to 6, and D is a higher diamond-like nucleus)
(B) at least one (meth)acrylic polymerizable monomer selected from the following components;
(B1) a hydroxyl group-containing (meth)acrylic monofunctional polymerizable monomer having at least one hydroxyl group and having one (meth)acrylic group in the molecule,
(B2) Epoxy group-containing (meth)acrylic monofunctional polymerizable monomer represented by the following formula

(In the formula,
R ³ and R ⁴ are each independently a hydrogen atom or a methyl group,
R ⁵ and R ⁶ are each independently an alkylene group having 1 to 4 carbon atoms which may be substituted with a hydroxy group, or

Is a group represented by
The average of a and b is 0 to 20 respectively)
(B3) a polyfunctional (meth)acrylic polymerizable monomer represented by the following formula;

(In the formula,
R ⁷ is a trivalent to hexavalent organic residue,
R ⁸ and R ⁹ are each independently a hydrogen atom or a methyl group,
c is an integer of 0 to 3 and d is an integer of 3 to 6),
(C) A photopolymerization initiator.

Another aspect of the present invention is a laminated body including an optical substrate and a cured body of the photocurable composition laminated on the surface of the optical substrate.

According to the present invention, it is possible to provide a photo-curable composition which is solvent-free, has very high scratch resistance, and has excellent transparency. Further, by using the photocurable composition, it is possible to obtain a cured product (cured film) having high scratch resistance and excellent transparency, and a laminate in which the cured product is laminated. ..

The reason why the photocurable composition of the present invention has the above effects is not clear, but it is presumed as follows. It is considered that since the higher diamond-like body nucleus portion of the polyfunctional polymerizable monomer having the higher diamond-like body nucleus used in the present invention has a rigid structure, the hardness becomes high and the extremely high scratch resistance is exhibited. .. In addition, since the polyfunctional polymerizable monomer has good compatibility with the (meth)acrylic polymerizable monomer, the polyfunctional polymerizable monomer is incorporated in the cured product in a state of being uniformly dispersed, and thus has excellent transparency. It is thought that sex develops.

The photocurable composition of the present invention can be suitably used for plastic substrates, but it can also be used as a coating agent for other optical substrates, for example, the surface of a substrate made of an inorganic material such as glass. is there.

The photocurable composition of the present invention is characterized by containing a combination of a polyfunctional polymerizable monomer having a specific higher diamond-like body nucleus and a specific (meth)acrylic polymerizable monomer. .. Hereinafter, each component constituting the photocurable composition of the present invention will be described in detail.

<(A) Polyfunctional polymerizable monomer having higher diamond-like body nucleus>
The polyfunctional polymerizable monomer (A) having a higher diamond-like nucleus (hereinafter sometimes referred to as the component (A)) used in the photocurable composition of the present invention is represented by the following formula (1). It is a compound.
Rn-D (1)
(R is an acrylic or methacrylic group, n is 2 to 6, and D is a higher diamond-like nucleus)
The higher diamond-like nuclei in formula (1) above are cage-shaped hydrocarbon molecules that retain a rigid structure that resembles small pieces of the diamond crystal lattice. The high-grade diamond-like nucleus is composed of multiple units, with adamantane as one unit. For example, diamantane contains two adamantane subunits that are face fused to each other, triamantane contains three adamantane subunits that are face fused to each other, and tetramantane is four adamantane subunits that are face fused to each other. Contains.

Specific examples of the higher diamond-like nucleus in the present invention include diamantane having 2-11 adamantane units, triamantane, tetramantane, pentamantane, hexamantane, heptamantane, octamantane, nonamantane, decamantane, and undecamantane. Be done. Among these, from the viewpoints of curability of the photocurable composition, adhesion between the cured film obtained by curing the photocurable composition and the plastic substrate, versatility, availability, etc., the adamantane unit Of 2 to 6 are preferred, and diamantane, triamantane, tetramantane, pentamantane, and hexamantane are preferred, and triamantane, tetramantane, pentamantane, and hexamantane having an adamantane unit of 3 to 6 are more preferred.

The polyfunctional polymerizable monomer having the higher diamond-like nucleus has 2 to 6 acrylic or methacrylic groups. Among them, the acrylic group or the methacrylic group is preferably 2 to 3 from the viewpoints of versatility and availability.

The acryl group or methacryl group may be directly bonded to the higher diamond-like nucleus or may be bonded via a group such as an alkyl group.

The polyfunctional polymerizable monomer having a higher diamond-like body nucleus represented by the above formula (1) can be synthesized by a known method. For example, when the number of acrylic groups or methacrylic groups is 2, it can be synthesized according to the method described in Non-Patent Document 1 using a commercially available diol having a higher diamond-like body nucleus as a raw material.

<(B) (meth)acrylic polymerizable monomer>
The photocurable composition of the present invention contains at least one (meth)acrylic polymerizable monomer (hereinafter sometimes referred to as the component (B)) selected from the following components. Each (meth)acrylic polymerizable monomer will be described.

<(B1) Hydroxyl group-containing monofunctional (meth)acrylic polymerizable monomer having at least one hydroxyl group in the molecule and having one (meth)acrylic group>
A hydroxyl group-containing monofunctional (meth)acrylic polymerizable monomer having at least one hydroxyl group and one (meth)acrylic group in the molecule (hereinafter sometimes referred to simply as (B1) component). ) Is not particularly limited, and commercially available products can be used. Specific examples of the component (B1) include hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate and hydroxybutyl (meth)acrylate. These may be used alone or in combination of two or more. Among these components (B1), from the viewpoint of the viscosity of the photocurable composition, the adhesion between the cured film obtained by curing the photocurable composition and the plastic substrate, versatility, and availability. Among them, hydroxyethyl (meth)acrylate and hydroxypropyl (meth)acrylate are particularly preferable.

<(B2) Epoxy group-containing monofunctional (meth)acrylic polymerizable monomer>
Examples of the epoxy group-containing monofunctional (meth)acrylic polymerizable monomer (hereinafter sometimes simply referred to as the component (B2)) include compounds represented by the following formula (2).

(In the formula,
R ³ and R ⁴ are each independently a hydrogen atom or a methyl group,
R ⁵ and R ⁶ are each independently an alkylene group having 1 to 4 carbon atoms which may be substituted with a hydroxy group, or

Is a group represented by
The average of a and b is 0 to 20).

Specific preferred examples of the component (B2) include glycidyl ethyl (meth)acrylate, glycidyl propyl (meth)acrylate, glycidyl butyl (meth)acrylate, glycidyl pentyl (meth)acrylate, glycidyl hexyl (meth)acrylate, Examples thereof include glycidyl heptyl (meth)acrylate and glycidyl octyl (meth)acrylate. These may be used alone or in combination of two or more. Of these components (B2), glycidyl ethyl (meth)acrylate, glycidyl propyl (from the viewpoint of the viscosity of the photocurable composition and the adhesion between the cured film obtained by curing the photocurable composition and the plastic substrate. (Meth)acrylate is particularly preferred.

<(B3) Polyfunctional (meth)acrylic polymerizable monomer>
Examples of the polyfunctional (meth)acrylic polymerizable monomer (hereinafter sometimes simply referred to as the component (B3)) include compounds represented by the following formula (3).

(In the formula,
R ⁷ is a trivalent to hexavalent organic residue,
R ⁸ and R ⁹ are each independently a hydrogen atom or a methyl group,
c is an integer of 0 to 3 and d is an integer of 3 to 6),
Here, as the trivalent to hexavalent organic residue in R ⁸ , specifically, the following formula

(In the formula, the number of broken lines indicates the number of bonds equal to the valence of R ^7. )
And the like. Among the above specific examples, the first organic group in the second row is, for example, the three broken lines extending from the carbon atom (C) to which the ethyl group (H ₃ CH ₂ C—) is bonded are the bonds of R ^7. That is, it indicates that it is a trivalent organic group. Similarly, in the next organic group, a total of 6 broken lines extending from each of the two carbon atoms bonded to the center —CH ₂ OCH ₂ — left and right respectively by 6 broken lines are the bonds of R ^7. , A hexavalent organic group. Among these, the following groups from the viewpoint of curability of the photocurable composition, adhesion between a cured film obtained by curing the photocurable composition and a plastic substrate, versatility, and availability. preferable.

Regarding c and d, it is preferable that c is 0 or 1 and d is 3 or 4 from the viewpoints of scratch resistance, adhesion between the cured film and the plastic substrate, appearance, viscosity that is easy to handle, and the like.

Specific preferred examples of the component (B3) include trimethylolpropane tri(meth)acrylate, trimethylolmethane tri(meth)acrylate, trimethylolethane tri(meth)acrylate, ethoxylated pentaerythritol tetra(meth)acrylate, penta. Erythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, dipentaerythritol penta(meth)acrylate, trimethylolpropane triethylene glycol tri(meth)acrylate, ditrimethylolpropane tetraacrylate And so on. These may be used alone or in combination of two or more. Among these (B3) components, pentaerythritol tetra(meth)acrylate is particularly preferable from the viewpoint of curability of the photocurable composition and adhesion between the cured film obtained by curing the photocurable composition and the plastic substrate. , Pentaerythritol tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, dipentaerythritol penta(meth)acrylate are particularly preferable.

Among them, the component (B3) is (B3a) a hydroxyl group-containing polyfunctional (meth)acrylic polymerizable monomer represented by the following formula (4) (hereinafter sometimes referred to simply as the component (B3a)). And a polyfunctional (meth)acrylic polymerizable monomer represented by the formula (3) excluding the (B3a) component and the (B3a) component (hydroxyl group-free polyfunctional (meth)acrylic polymerization). It is more preferable from the viewpoint of production that it is a mixture of the organic monomer and the component (B3b).

(In the formula,
R ¹¹ and R ¹² are each independently a hydrogen atom or a methyl group,
R ¹⁰ is a 4- to 6-valent organic residue,
e is an integer of 0 to 3 and f is an integer of 3 to 5)
Here, as the 4- to 6-valent organic residue for R ¹⁰ , specifically, a group represented by the following formula is preferable.

(In the formula, the number of broken lines indicates the number of bonds equal to the valence of the formula R ¹⁰ )
Of the above specific examples, for example, the second organic group is a hexavalent organic group as described above, but it is understood that one of the six bonds is bonded to HOH ₂ C-. Should be.

Regarding e and f, it is preferable that e is 0 or 1 and f is 3 from the viewpoints of scratch resistance of the cured film, adhesion between the cured film and the plastic substrate, appearance, and viscosity that is easy to handle. ..

Specific preferred examples of the component (B3a) include pentaerythritol tri(meth)acrylate and dipentaerythritol penta(meth)acrylate. Of these, pentaerythritol tri(meth)acrylate is particularly preferable from the viewpoint of curability of the photocurable composition and adhesion between the cured film obtained by curing the photocurable composition and the plastic substrate.

The component (B3b) is pentaerythritol tetra(meth)acrylate, trimethylolpropane tri(meth)acrylate, or dipentaerythritol hexa(meth)acrylate. In particular, when the component (B3) is composed of the preferred component (B3b), the productivity of the component (B3) itself is taken into consideration that the component (B3b) is pentaerythritol tetra(meth)acrylate or dipentaerythritol hexa(meta). ) Acrylate is preferable, and pentaerythritol tetra(meth)acrylate is particularly preferable.

When the component (B1) and/or the component (B2) is used, by using the (B3a) hydroxyl group-containing polyfunctional (meth)acrylic polymerizable monomer, the component (B1) and/or the component (B2) can be obtained. , (B3) component can be further increased in compatibility, and appearance defects can be further suppressed.

<Preferable blending ratio of component (B)>
The distribution ratio of the component (B) in the photocurable composition of the present invention is appropriately selected in consideration of the type of plastic substrate used, the strength of the cured film obtained by curing the photocurable composition of the present invention, and the like. can do. Above all, from the viewpoint of the adhesion between the plastic substrate and the cured film, the scratch resistance of the cured film, and the appearance, the content of the component (B) is 10 to 900 parts by mass per 100 parts by mass of the component (A). Is preferred, 50 to 850 parts by mass is more preferred, and 100 to 800 parts by mass is most preferred.

In the present invention, at least one selected from the component (B1), the component (B2) and the component (B3) may be used, and a plurality of components may be combined.

When the component (B1) is used, it is preferably used in combination with the component (B2). The blending ratio when these are used in combination can be appropriately determined in consideration of the type of the plastic substrate used, the strength of the cured film obtained by curing the photocurable composition of the present invention, and the like. Among them, from the viewpoint of adhesion between the plastic substrate and the cured film, scratch resistance of the cured film, and appearance, the mass ratio of the (B2) component to the (B1) component ((B1)/(B2)). Is preferably 0.3 to 4, more preferably 0.5 to 3, and even more preferably 0.7 to 1.5.

When the component (B3a) and the component (B3b) are used in combination, when the mixture of the component (B3a) and the component (B3b) (the total amount of the component (B3)) is 100 parts by mass, the component (B3a) is The component is preferably 0.001 to 60 parts by mass, the (B3b) component is preferably 40 to 99.999 parts by mass, the (B3a) component is 5 to 35 parts by mass, and the (B3b) component is 65 to 95 parts by mass. It is more preferable to set it as a mass part.

<(C) Photopolymerization initiator>
The photocurable composition of the present invention is cured by irradiating with ultraviolet rays after applying the composition to a plastic substrate. As the photopolymerization initiator used in the photocurable composition of the present invention (hereinafter sometimes simply referred to as the component (C)), a known photopolymerization initiator used for photocuring can be used. .. The following compounds may be mentioned as specific examples of the photopolymerization initiator.

In the present invention, the component (C) is not particularly limited, but the component (C1) acylphosphine oxide-based polymerization initiator (hereinafter sometimes referred to simply as the component (C1)) is an essential component. Is preferred. In order to form a cured film having higher performance even in air, (C2) an intramolecular cleavage type polymerization initiator other than the above-mentioned (C1) component (hereinafter may be simply referred to as (C2) component) is included. Preferably.

Specific preferred examples of the component (C1) include benzoyl-diphenylphosphine oxide, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, 2,3,5,6-tetramethylbenzoyl-diphenylphosphine oxide, 3,4-Dimethylbenzoyl-diphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, bis(2,6-dimethoxybenzoyl)(2,4,4-trimethyl-pentyl)phosphine Examples thereof include oxide and bis(2,6-dimethylbenzoyl)ethylphosphine oxide. Among the above-mentioned component (C1), benzoyl-diphenylphosphine oxide and 2,4,6-trimethylbenzoyl-diphenylphosphine from the viewpoint of curability of the photocurable composition and adhesion between the cured film and the plastic substrate. It is preferable to use oxide, 2,3,5,6-tetramethylbenzoyl-diphenylphosphine oxide, or 3,4-dimethylbenzoyl-diphenylphosphine oxide.

In the present invention, preferred specific examples of the component (C2) include α-hydroxyacetophenone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1,2-methyl-1-. Examples thereof include alkylphenone compounds such as [4-(methylthio)phenyl]-2-morpholino-propanone-1, benzoin ether compounds such as benzoin and benzoin alkyl ether, and phenylglyoxylic acid methyl ester. Among the components (C2), it is preferable to use an alkylphenone compound agent from the viewpoint of the adhesion between the cured film and the plastic substrate and the scratch resistance of the cured film. These may be used alone or in combination of two or more.

<Preferable blending ratio of (C)>
The blending ratio of the component (C) varies depending on the polymerization conditions, the type of initiator, the type and composition of the polymerizable monomer, and cannot be unconditionally limited. For example, the component (A) and the component (B) which are the polymerization components. It is preferable to use it in the range of 0.01 to 10 parts by mass based on 100 parts by mass of the total components. When using a plurality of types of component (C), the total amount should satisfy the above-mentioned mixing ratio.

Further, as described above, in the present invention, it is preferable to use the component (C1) and the component (C2) in combination. In this case, the blending ratio of the component (C1) and the component (C2) depends on the type of the plastic substrate used, the strength of the cured film obtained by curing the photocurable composition of the present invention, and the adhesion to the substrate. Can be appropriately determined in consideration of the above.

Among them, the mass ratio of (C2) to (C1) ((C2)/(C1)) is from the viewpoints of adhesion between the plastic substrate and the cured film, scratch resistance of the cured film, and appearance. , 0.1 to 10, preferably 0.2 to 5, and most preferably 0.4 to 1.5.

Next, optional components that can be contained in the photocurable composition of the present invention will be described as long as the effects of the present invention are not impaired.

<(D) Radical scavenger>
The photocurable composition of the present invention may contain a radical scavenger (D) (hereinafter sometimes referred to simply as the component (D)). The (D) radical scavenger is generally blended with the resin, and known ones can be used as long as they have a capability of trapping radicals generated by decomposition of the resin and the like.

By containing the component (D), storage stability is improved, and the excellent characteristics originally possessed by the photocurable composition can be exhibited even after long-term storage. For example, a hindered phenol radical scavenger or a hindered amine radical scavenger is mentioned.

Preferred hindered phenol radical scavengers include, for example, ethylenebis(oxyethylene)bis[3,5-tert-butyl-4-hydroxy-m-toluyl]propionate, octadecyl-3-(3,5-di-tert-). Butyl-4-hydroxyphenyl)propionate, pentaerythritol tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, thiodiethylenebis[3-(3,5-di-tert-butyl- 4-hydroxyphenyl]propionate, tris-(2-methyl-4-hydroxy-5-tert-butylphenyl)-butane, 4,4'-butylidenebis(3-methyl-6-tert-butylphenol), tris-(3 ,5-di-tert-butyl-4-hydroxyphenyl)isocyanurate, 2,4,6-tris[3,5-di-tert-butyl-4-hydroxybenzyl]-1,3,5-trimethylbenzene, 4-[[4,6-bis(octylthio)-1,3,5-triazin-2-yl]amino]-2,6-bis(1,1-dimethylethyl)phenol may be mentioned.

Preferred hindered amine radical scavengers include, for example, bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis(1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, bis( 1-octyloxy-2,2,6,6-tetramethyl-4-piperidyl) sebacate, 1-[2-{3-(3,5-di-t-butyl-4-hydroxyphenyl)propionyloxy}ethyl ]-4-{3-(3,5-Di-t-butyl-4-hydroxyphenyl)propionyloxy}-2,2,6,6-tetramethylpiperidine, 4-benzoyloxy-2,2,6, 6-tetramethylpiperidine, methyl(1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, 1,2,2,6,6-pentamethyl-4-piperidinyl methacrylate, 2-[[3 ,5-Bis(1,1,-dimethylethyl)-4-hydroxyphenyl]methyl]-2-butylpropanedioic acid [1,2,2,6,6-pentamethyl-4-piperidinyl], poly[{6 -(1,1,3,3-Tetramethylbutyl)amino-1,3,5-triazine-2,4-diyl}{(2,2,6,6-tetramethyl-4-piperidyl)imino}hexa Methylene {(2,2,6,6-tetramethyl-4-piperidyl)imino}] and the like.

These radical scavengers can be used alone or as a mixture of two or more.

Among these radical scavengers, the component (D) preferably contains a compound having a 2,2,6,6-tetramethyl-4-piperidyl skeleton in order to maintain high physical properties after long-term storage. Among them, the component (D) is a compound represented by the following formula (5):

(In the formula, R ¹³ and R ¹⁴ are each independently a hydrogen atom or a methyl group, and g is an integer of 5 to 12.)
It is preferable to include. Examples of preferable compounds represented by the formula (4) include bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate and bis(1,2,2,6,6-pentamethyl-4-piperidyl). ) Examples include sebacate.

Among the radical scavengers, an excellent effect is exhibited by adding a compound having a 2,2,6,6-tetramethyl-4-piperidyl skeleton, particularly a compound represented by the formula (5). From these facts, it is considered that these radical scavengers have good compatibility with the components (A) and (B) used in the present invention, and more effectively, a radical containing the components (A) and (B). The long-term storage stability of the photocurable composition of the invention can be enhanced.

In the present invention, the amount of the component (D) used is not particularly limited, but the adhesiveness between the obtained cured film and the plastic substrate, scratch resistance of the cured film, appearance, and preservation of the composition From the viewpoint of the stabilizing effect, the amount of the component (D) used is preferably in the range of 0.005 to 10 parts by mass, particularly 0.01 per 100 parts by mass of the components (A) and (B). It is particularly preferable that the range is from 1 to 1 part by mass.

<(E) N-vinylamide compound>
The photocurable composition of the present invention contains (E) an N-vinylamide compound represented by the following formula (1) (hereinafter sometimes referred to as the (E) component) from the viewpoint of improving scratch resistance. Preferably.

(In the formula,
R ¹ and R ² are each independently a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms, or
R ¹ and R ² may be bonded to each other to form a hydrocarbon group having 2 to 6 carbon atoms. ),
Here, in R ¹ and R ² , the hydrocarbon group having 1 to 5 carbon atoms is the curability of the photocurable composition, and the cured film obtained by curing the photocurable composition and the plastic substrate. It is specified from the viewpoint of adhesion, versatility, and availability. It is particularly preferably a hydrocarbon group having 1 to 3 carbon atoms. Specific examples include a methyl group, an ethyl group, a propyl group, a vinyl group and the like.

Further, when R ¹ and R ² are bonded to each other to form a hydrocarbon group having 2 to 6 carbon atoms, the N-vinylamide compound has a β-lactam (having 2 carbon atoms), depending on the carbon number. It forms γ-lactam (having 3 carbon atoms), δ-lactam (having 4 carbon atoms), ε-lactam (having 5 carbon atoms), ω-lactam (having 6 carbon atoms), and the like. Any of these hydrocarbon groups can be preferably used as the group of the N-vinylamide compound used in the present invention. The carbon number of the hydrocarbon group refers to the total carbon number of R ¹ and R ² . The hydrocarbon group may have a substituent such as an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 14 carbon atoms. The number of carbon atoms of the hydrocarbon group does not include the number of carbon atoms of these substituents and represents the number of carbon atoms of all ring members constituting the ring members of the lactam ring minus 1 (carbon of carbonyl). ..

Preferred specific examples of the N-vinylamide compound represented by the above formula (1) include N-vinyl-β-lactam, N-vinylpyrrolidone, N-vinyl-valerolactam, N-vinylcaprolactam, N-vinylformamide, and N-vinylformamide. -Methyl-N-vinylformamide, N-vinylacetamide, N-methyl-N-vinylacetamide, N-ethyl-N-vinylacetamide, N-vinylpropionamide, N-methyl-N-vinylpropionamide and the like. .. These may be used alone or in combination of two or more.

Among these N-vinylamide compounds, the curability of the photocurable composition, the adhesion between a cured film obtained by curing the photocurable composition and a plastic substrate, versatility, availability, and the like From the viewpoint, N-vinylpyrrolidone, N-vinylcaprolactam, and N-vinylacetamide are particularly preferable.

In the present invention, the blending ratio of the component (E) is not particularly limited, but from the viewpoint of scratch resistance of the obtained cured film, the total amount of the component (A) and the component (B) is 100 parts by mass. Therefore, it is preferable to use it in the range of 10 to 100 parts by mass.

<Other compounding ingredients>
Further, various compounding agents can be added to the photocurable composition of the present invention as long as the effects of the present invention are not impaired. Examples of various compounding agents include additives such as surfactants, ultraviolet absorbers, anti-coloring agents, antistatic agents, fluorescent dyes, dyes, pigments, fragrances and plasticizers.

Among the above-mentioned compounding agents, as the surfactant, known surfactants such as a silicone-based surfactant having a silicone group (polyalkylsiloxane unit) as a hydrophobic group and a fluorine-based surfactant having a fluorocarbon chain are known. Surfactants can be preferably used. Specific examples of silicone-based surfactants and fluorine-based surfactants that can be preferably used include "L-7001", "L-7002", "L-7604", and "FZ-2123" manufactured by Toray Dow Corning Co., Ltd. ], "Megafuck F-470", "Megafuck F-1405", "Megafuck F-479" manufactured by DIC Co., Ltd., "Flowrad FC-430" manufactured by 3M Japan K.K. (Sumitomo 3M Ltd.), and the like. be able to. The surfactants may be used alone or in combination of two or more. The amount of the surfactant used is preferably in the range of 0.001 to 10 parts by mass based on 100 parts by mass of the total of the components (A) and (B).

<Method for preparing photocurable composition and method for forming cured body (cured film) of the composition>
The photocurable composition of the present invention may be prepared by weighing out and mixing a predetermined amount of each component. The order of addition of each component is not particularly limited, and all components may be added at the same time. Further, the component (A) and the component (B) may be mixed in advance, and then the component (C) and other additives may be added and mixed.

The laminate of the present invention is produced by applying the photocurable composition onto a plastic substrate, photocuring and laminating the composition. The plastic base material to which the photocurable composition is applied is not particularly limited, and examples thereof include known plastic base materials such as eyeglass lenses, window glasses for houses and automobiles, camera lenses, liquid crystal displays and the like.

Known eyeglass lenses are plastic eyeglass lenses such as (meth)acrylic resin, polycarbonate resin, allyl resin, thiourethane resin, urethane resin and thioepoxy resin. When using the photocurable composition of the present invention, any of these spectacle lenses can be used.

As a method for applying the photocurable composition of the present invention to the surface of a plastic substrate, a known application method can be adopted, and examples thereof include a spin coating method, a dip coating method, a bar coating method and a spray method. .. Moreover, since the photocurable composition of the present invention has a low viscosity, it is easy to form a thin film.

The photocurable composition of the present invention is applied onto the surface of the above-mentioned optical substrate to form a coating film, and the coating film is photopolymerized and cured (cured product (cured film)) to form a laminate. When forming a laminated body using the photocurable composition of the present invention, sufficient adhesion is exhibited without pretreatment of the optical substrate. However, if it is desired to further improve the wettability and adhesion to the substrate, it is preferable to pretreat the optical substrate prior to coating. Examples of such pretreatment include chemical treatment with a basic aqueous solution or acidic aqueous solution, polishing treatment with an abrasive, plasma treatment with atmospheric pressure plasma and low pressure plasma, corona discharge treatment, UV ozone treatment, etc. Can be mentioned. These methods may be used in combination in order to improve the adhesion of the optical substrate.

Among the pretreatment methods, as a method that can be used particularly easily, a chemical treatment with a basic solution is particularly suitable as the pretreatment of the above-mentioned spectacle lens substrate (optical substrate). The adhesiveness of can be made stronger. The treatment method is carried out by impregnating an alkaline aqueous solution with an optical substrate or by ultrasonic cleaning while impregnating the optical substrate with an alkaline aqueous solution. As the alkaline solution, for example, a sodium hydroxide aqueous solution or a potassium hydroxide aqueous solution is used. The hydroxide concentration is preferably 5 to 30% by mass. The treatment temperature may be appropriately determined in consideration of the heat resistance of the substrate used, but is preferably in the range of 20 to 60°C. The treatment time varies depending on the treatment conditions, but is preferably 1 minute to 1 hour, more preferably 5 to 15 minutes. In addition to the alkaline aqueous solution, for example, a mixed solution of water and an alcohol solvent, or an alcohol solution may be used. Examples of the alcohol to be used include lower alcohols such as methanol, ethanol and isopropyl alcohol, and as a small amount of an additive, an organic base such as 1-methyl-2-pyrrolidone in an amount of 1 to 10 parts by mass with respect to 100 parts by mass of the alkaline solution. What added the mass part may be sufficient. After the alkali treatment, it may be rinsed with water such as pure water, ion-exchanged water, or distilled water, and then dried.

The photocurable composition is applied to the optical substrate by the above method and photocured to form a laminate. In the laminate obtained by the above method, the thickness of the layer (cured film thickness) of the cured product of the photocurable composition is preferably 1 μm or more and 20 μm or less, more preferably 1 μm or more and 5 μm or less. The cured product can be obtained, for example, by applying the photocurable resin to a thickness of 1 μm or more and 20 μm or less and irradiating it with ultraviolet rays to form a cured film.

The photocurable composition of the present invention can be cured under an inert gas atmosphere or an air atmosphere by using ultraviolet rays emitted from a light source such as a xenon lamp, a high pressure mercury lamp, or a metal halide lamp. UV irradiation conditions can be set appropriately as necessary, preferably integrated light quantity 0.4 J / cm ² or more, more preferably 1.7 J / cm ² or more, 10J / cm ² to become as follows Is set to. In the present invention, the laminate having the cured film obtained from the photocurable composition of the present invention on the optical substrate may be further subjected to secondary processing. Specifically, a further hard coat layer can be formed on the cured film. As the hard coat agent for forming the hard coat layer, known ones can be used. Specifically, a silane coupling agent, a hard coating agent containing a sol of an oxide such as silicon, zirconium, antimony, aluminum or titanium as a main component, or a hard coating agent containing an organic polymer as a main component can be used. .. Examples of the method for applying the hard coat agent include methods such as dip coating, spin coating, and dip spin coating. This coated hard coat agent can be cured by a known method, for example, by heating to form a hard coat layer.

Hereinafter, the present invention will be further described with reference to examples, but the present invention is not limited to these examples. Moreover, not all combinations of the features described in the embodiments are essential to the solving means of the present invention.
First, the names and abbreviations of the components used in the present invention will be described.

Component (A): Polyfunctional Polymerizable Monomer Having Higher Diamond-Like Nuclei Diamantane Diacrylate Triamantane Diacrylate Undecamantane Diacrylate (B) Component: (Meth) Acrylic Monofunctional Polymerizable Monomer A- TMM-3: pentaerythritol triacrylate; (B3a) component A-TMMT: pentaerythritol tetraacrylate; (B3b) component (C) component: photopolymerization initiator TPO: bis(2,4,6-trimethylbenzoyl)phenylphosphine Finoxide; (C1) component I184: 1-hydroxy-cyclohexyl-phenyl-ketone; (C2) component (E) component: radical scavenger T765: bis(1,2,2,6,6-pentamethyl-4) sebacate -Piperidyl)
<Production of laminated body>
As a plastic substrate, a plastic lens made of a polycarbonate resin (refractive index 1.59), a plastic lens made of an aryl dicarbonate resin (refractive index 1.50), a thiourethane-based lens (refractive index 1.60, and 1.67). ) Was used. After wiping this plastic optical substrate with isopropyl alcohol, the photocurable composition shown in Table 1 was applied by spin coating. This coating film was irradiated with an ultraviolet ray of 75 mW/cm ² for 60 seconds using an ECE5000 (manufactured by Dymax) equipped with a mercury lamp to cure the coating film, and a cured product of the photocurable resin composition (curing). A laminated body in which the films) were laminated was obtained. The following evaluation was performed on the obtained laminate. Table 2 shows the thickness of the cured film. Further, in Table 2, "PC" is used when the used polycarbonate resin is used, "CR39" is used when the aryl dicarbonate resin is used, and "MR7" and "MR8" are used when the thiourethane lens is used. I wrote. In addition, in Table 2, "nitrogen" is described when the cured atmosphere is a nitrogen atmosphere, and "air" is described when the cured atmosphere is an air atmosphere.

<Evaluation method of laminated body>
1. Adhesion Adhesion was evaluated by a cross-cut test. That is, a cutter knife is used on the surface of the laminated body (cured film) on which the cured body (cured film) of the photocurable composition is laminated by the method described in the above <Production of Laminate> Was added to form 100 squares. Cellophane adhesive tape (cellophane tape (registered trademark) manufactured by Nichiban Co., Ltd.) was strongly adhered onto it, and after pulling at once in a 90° direction from the surface and peeling it off, the squares with the cured film remaining (in 100 squares) The number of remaining squares) was measured and evaluated according to the following three grades.

A: 100/100
B: 99/100 to 95/100
C: less than 95/100 2. Boiled adhesiveness After immersing the laminated body produced by the method described in <Production of laminated body> in boiling water for 1 hour, the laminated body is taken out, water droplets are wiped off, and the adhesiveness evaluation method described above is used. Similarly, the adhesiveness was evaluated. After the evaluation, each laminate was immersed again in boiling water. This operation was repeated 3 times, and the test was performed until the boiling time reached 3 hours in total.

3. Steel Wool Scratch Resistance Test Laminate the surface of the laminate produced by the method described in <Production of Laminate> with steel wool (Nippon Steel Wool Co., Ltd. Bonster #0000) under a load of 1 kg. The body surface was rubbed 10 times back and forth, and the degree of damage was visually evaluated to the following 4 grades. The evaluation criteria are as follows.

A: Almost no scratch (visually less than 5 scratches)
B: Very slight damage (visually 5 or more and less than 15 scratches)
C: Slightly scratched (visually 15 or more and less than 40 scratches)
D: Scratched (visually 40 or more scratches)
E: uncured (cured film is not sufficiently cured and has an uncured portion)
Production example 1
Synthesis of Diamantane Diacrylate (Component (A)) Using commercially available diamantanediol as a raw material, a diamantane diacrylate represented by the following formula was synthesized according to the method described in Non-Patent Document 1.

Production example 2
Synthesis of Triamantane Diacrylate (Component (A)) Using commercially available triamantanediol as a raw material, triamantane diacrylate (A; component (A)) was synthesized in the same manner as in Production Example 1.
Production Example 3
Synthesis of Undecamantane Diacrylate (Component (A)) Undecamantane diacrylate (Component (A)) was synthesized by the same method as in Production Example 1 using commercially available undecamantane diol as a raw material.
Example 1
35 parts by mass of pentaerythritol triacrylate (B3a; (B) component) and 315 parts by mass of pentaerythritol tetraacrylate (B3b; (B) component) per 100 parts by mass of diamantane diacrylate ((A) component). , Bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide (C1; (C) component) 10 parts by mass, 1-hydroxy-cyclohexyl-phenyl-ketone (C2; (C) component) 5 parts by mass. , T765 (E component) and 0.1 part by mass of a surfactant L-7001 were mixed to prepare a photocurable composition. Table 1 shows the blending ratio of the photocurable composition.

Using the obtained photocurable composition, a laminate was manufactured according to the method described in <Production of laminate>. The obtained laminate was evaluated for adhesion, boiling adhesion, and scratch resistance according to the method described in <Evaluation method for laminate> above. The results are shown in Table 2.
Example 2
A photocurable composition having a compounding ratio shown in Table 1 was prepared in the same manner as in Example 1 except that triamantane diacrylate (A; component (A)) was used instead of diamantane diacrylate. .. The obtained photocurable composition was cured in an optical base material and a curing atmosphere shown in Table 2 to produce a laminate. The obtained laminate was evaluated in the same manner as in Example 1, and the results are summarized in Table 2.
Example 3
A photocurable composition having the compounding ratio shown in Table 1 was prepared in the same manner as in Production Example 1 except that undecamantane diacrylate (A; component (A)) was used instead of diamantane diacrylate. . However, undecamantane diacrylate did not dissolve in the component (B) to the same amount as diamantane diacrylate or triamantane diacrylate, and there was an insoluble portion, so photocuring and curing products were not evaluated. .
Comparative Example 1
A photocurable composition having the compounding ratio shown in Table 1 was prepared in the same manner as in Example 1 except that the polyfunctional polymerizable monomer having a higher diamond-like nucleus was not compounded. The obtained photocurable composition was cured in an optical base material and a curing atmosphere shown in Table 2 to produce a laminate. The obtained laminate was evaluated in the same manner as in Example 1, and the results are summarized in Table 2.

As is clear from the results summarized in Table 2, a photocurable composition containing a polyfunctional polymerizable monomer having a higher diamond-like body nucleus provides high adhesion to an optical substrate and high scratch resistance. It became clear that it became a composition which has.

Claims (4)

(A) a polymerizable monomer represented by the following formula (1),
Rn-D (1)
(R is an acrylic or methacrylic group, n is 2 to 6, and D is a higher diamond-like nucleus)
(B) at least one (meth)acrylic polymerizable monomer selected from the following components;
(B1) a hydroxyl group-containing (meth)acrylic monofunctional polymerizable monomer having at least one hydroxyl group and having one (meth)acrylic group in the molecule,
(B2) Epoxy group-containing (meth)acrylic monofunctional polymerizable monomer represented by the following formula

(In the formula,
R ³ and R ⁴ are each independently a hydrogen atom or a methyl group,
R ⁵ and R ⁶ are each independently an alkylene group having 1 to 4 carbon atoms which may be substituted with a hydroxy group, or

Is a group represented by
The average of a and b is 0 to 20, respectively. )
(B3) a polyfunctional (meth)acrylic polymerizable monomer represented by the following formula;

(In the formula,
R ⁷ is a trivalent to hexavalent organic residue,
R ⁸ and R ⁹ are each independently a hydrogen atom or a methyl group,
c is an integer of 0 to 3 and d is an integer of 3 to 6. ),
A photocurable composition comprising (C) a photopolymerization initiator. Based on 100 parts by mass of the polymerizable monomer represented by the formula (1) (1),
10 to 900 parts by mass of a (meth)acrylic polymerizable monomer as the (B),
The photocurable composition according to claim 1, comprising. The photocurable composition according to claim 1, wherein the higher diamond-like nucleus is diamantane, triamantane, tetramantane, pentamantane, hexamantane, heptamantane, octamantane, nonamantane, decamantane, undecamantane. A laminate comprising an optical substrate and a cured product of the photocurable composition according to any one of claims 1 to 4, which is laminated on the surface of the optical substrate.