JP5976348B2 - Active energy ray-curable resin composition, method for producing the same, coating agent, and laminate - Google Patents

Description

  The present invention relates to an active energy ray-curable resin composition, a production method thereof, a coating agent, and a laminate, and more specifically, an activity for forming a coating film excellent in low refractive index, scratch resistance, and transparency. The present invention relates to an energy ray curable resin composition and a production method thereof, and a coating agent and a laminate using the energy ray curable resin composition.

  Conventionally, in order to make display display easy to see, an antireflection film is laminated on the display surface. In order to maximize the effect of this anti-reflection film, it is usually often used as a structure in which a high refractive index layer and a low refractive index layer are sequentially laminated on a transparent resin substrate. ing.

  Here, since the low refractive index layer is a layer located on the outermost surface of the antireflection film, it is important to impart scratch resistance. On the other hand, the low refractive index layer has a thickness less than the visible light wavelength, preferably about 1/4 of the visible light wavelength in order to exhibit the effect. Yes.

  For this reason, in order to impart scratch resistance, a hard coat layer is applied and formed as a low refractive index layer, but active as a low refractive index layer forming material in order to increase productivity. An energy ray curable resin, particularly an ultraviolet curable resin is often used. The ultraviolet curable resin uses a photopolymerization initiator that generates radicals and / or cations when irradiated with ultraviolet rays, whereby the ultraviolet curable resin is radically or / and cationically polymerized.

  However, as described above, it is preferable that the low refractive index layer has a thickness of less than a visible light wavelength, specifically, a thickness of less than 1 μm. When using a curable resin to form a radical (photoradical polymerization initiator) that generates radicals as the photopolymerization initiator, radicals generated by light irradiation are exposed at the film interface in the atmosphere. There was a problem that it quickly deactivated by reacting with oxygen, and as a result, it was difficult to give scratch resistance. For this reason, for example, a method for solving the above problem by substituting the ultraviolet irradiation portion with nitrogen is known, but a new problem arises that new equipment investment is required.

For this reason, several methods have been proposed to use a so-called photocationic polymerization initiator that generates cations by light irradiation as a photopolymerization initiator and to ensure scratch resistance by using silica. Yes. For example, a reactive silica having a particle size of 1 to 200 nm having a radical polymerizable group or a cationic polymerizable group, a fluorine-containing vinyl monomer polymer unit, and a polymer unit having a radical polymerizable group or a cationic polymerizable group in the side chain An antireflective film having a low refractive index layer made of a cured film using a copolymerizable composition containing the above has been proposed (see Patent Document 1). In addition, inorganic oxide fine particles mainly composed of colloidal silica, and —O—Si—R ¹ —S— bond (R ¹ is a linear or branched alkylene group having 1 to 10 carbon atoms) to the inorganic oxide fine particles. Organic-inorganic hybrid resin composition comprising an organic-inorganic composite having an organic polymer having a side chain having a ring-opening polymerizable group capable of photocationic polymerization, and a cationically polymerizable photoinitiator. It has been proposed to cure a product to form a film with high hardness (see Patent Document 2).

JP 2004-93947 A JP 2005-336255 A

  However, in the technique disclosed in Patent Document 1, it is supposed to have a radically polymerizable group or a cationically polymerizable group as silica that is a reactive fine particle, but when silica having a radically polymerizable group is used, it is less than 1 μm. This film thickness is not preferable because oxygen inhibition during the curing reaction is remarkable, and a large amount of radical photopolymerization initiator is used or a large amount of ultraviolet irradiation is required. In addition, when using a silica having a cationic polymerizable group, the photo cationic polymerization initiator needs to be close to the silica surface, but strongly binds and aggregates with the originally acidic silica surface, so that it is a pot as a coating agent. There is a problem that life is significantly shortened.

  On the other hand, in the technique disclosed in Patent Document 2, since the surface of the inorganic oxide fine particles is covered with an organic polymer, the photocationic polymerization initiator is not close enough to the surface of the inorganic oxide fine particles to cause aggregation. However, since the resulting organic / inorganic composite is bonded to inorganic oxide fine particles only at the end of the organic polymer, the coating of inorganic oxide fine particles contributes to lowering the refractive index and scratch resistance. However, the organic polymer effective only in the portion close to the inorganic oxide fine particles is poor in efficiency and it is difficult to exert the effect of imparting scratch resistance, and the scratch resistance is not sufficiently satisfactory.

  The present invention has been made in view of such circumstances, and can form a film thickness that is less than the visible light wavelength, and can form a cured film that is excellent in transparency, low refractive index, and scratch resistance. It is an object of the present invention to provide an active energy ray-curable resin composition that can be used, a method for producing the same, a coating agent, and a laminate.

That is, the present inventor has conducted extensive research to achieve the above object, and as a result, the active energy ray-curable resin composition containing the photocationic polymerization initiator contains a hydroxyl group and a fluorine atom-containing structural site. And an epoxy resin-containing acrylic resin (A) and a colloidal silica-based inorganic oxide fine particle (B) having both an alkoxy group and an isocyanate group in one molecule (E) When the inorganic oxide-acrylic resin composite (α) formed through the binding site represented by the following general formula (1) is used, the chain of the acrylic resin (A) and the inorganic oxidation are used. Bonding points with the product fine particles (B) are present at random, the inorganic oxide fine particles (B) can be effectively covered with the acrylic resin (A), and the cationic photopolymerization initiator is Since it is not close to the surface of the inorganic oxide fine particles (B) to the extent that it collects, it has excellent pot life as a coating agent, and excellent scratch resistance even at a film thickness required for reducing the refractive index by photocationic polymerization. An active energy ray-curable resin composition for obtaining a cured coating film was found and the present invention was completed.

In the present invention, an acrylic resin (A) containing a hydroxyl group and containing a fluorine atom-containing structural site and an epoxy group, and inorganic oxide fine particles (B) containing colloidal silica as a main component contain one molecule. An inorganic oxide-acrylic resin composite (α) formed by bonding through a bonding site represented by the following general formula (1) derived from a silicon compound (E) having both an alkoxy group and an isocyanate group therein; An active energy ray-curable resin composition containing a cationic photopolymerization initiator (β) is a first gist.
[Chemical 1]
—O—Si—R ¹ —NHCOO— (1)
In [the formula (1), R ¹ is a linear or branched alkylene group having 1 to 10 carbon atoms. ]

And this invention is a manufacturing method of the active energy ray curable resin composition which is the said 1st summary,
[I] A co-polymer containing a fluorine atom-containing (meth) acrylic acid ester monomer (a1), an epoxy group-containing (meth) acrylic acid ester monomer (a2) and a hydroxyl group-containing (meth) acrylic acid ester monomer (a3). A step of producing an acrylic resin (A) containing a fluorine atom-containing structural site and an epoxy group by copolymerizing the polymerization component [I];
[Ii] After reacting the hydroxyl group in the acrylic resin (A) with the isocyanate group of the silicon compound (E) having both an alkoxy group and an isocyanate group in one molecule, the alkoxy group in the reaction product By reacting with the hydroxyl group in the inorganic oxide fine particles (B) containing colloidal silica as a main component, the acrylic resin (A) and the inorganic oxide fine particles (B) containing colloidal silica as a main component are: A step of producing an inorganic oxide-acrylic resin composite (α) formed by binding via a binding site represented by the general formula (1);
[Chemical formula 2]
—O—Si—R ¹ —NHCOO— (1)
In [the formula (1), R ¹ is a linear or branched alkylene group having 1 to 10 carbon atoms. ]
[Iii] A second summary of a method for producing an active energy ray-curable resin composition comprising a step of mixing a photocationic polymerization initiator (β) together with the inorganic oxide-acrylic resin composite (α). It is what.

Furthermore, this invention makes the coating agent formed by containing the active energy ray-curable resin composition which is the said 1st summary into a 3rd summary, and on a transparent base material surface, it is 3rd summary. A laminate in which an antireflection film is formed using a certain coating agent is a fourth gist.

As described above, the active energy ray-curable resin composition of the present invention is mainly composed of acrylic resin (A) containing a hydroxyl group and containing a fluorine atom-containing structural portion and an epoxy group, and colloidal silica. And inorganic oxide fine particles (B) to be bonded through a bonding site represented by the general formula (1) derived from the silicon compound (E) having both an alkoxy group and an isocyanate group in one molecule. An oxide-acrylic resin composite (α) and a photocationic polymerization initiator (β) are contained. For this reason, since the acrylic resin (A) efficiently coats the inorganic oxide fine particles (B), the photocationic polymerization initiator (β) aggregates on the surface of the inorganic oxide fine particles (B). It will not be close enough to cause it to occur and will have an excellent pot life. Furthermore, a coating film having excellent scratch resistance can be obtained even when the thickness is less than 1 μm and required for reducing the refractive index by cationic photopolymerization. Moreover, since the acrylic resin (A) has a low refractive index and is bonded to the inorganic oxide fine particles (B), it is used as a material for forming the outermost surface layer of a laminate such as an antireflection film. Even so, it becomes possible to prevent the silica particles from falling off the rubbed film, and a coating film excellent in maintaining scratch resistance can be obtained. Therefore, by using the active energy ray-curable resin composition of the present invention, it is possible to obtain a laminate in which an antireflection film excellent in scratch resistance as well as a low refractive index is formed.

The description of the constituent requirements described below is an example (representative example) of the embodiment of the present invention, and is not limited to these contents.
In the present invention, (meth) acrylic acid is acrylic acid or methacrylic acid, (meth) acryl is acrylic or methacrylic, (meth) acryloyl is acryloyl or methacryloyl, and (meth) acrylate is acrylate or Each means methacrylate.
Hereinafter, the present invention will be described in detail.
In the active energy ray-curable resin composition of the present invention, a specific acrylic resin (A) and inorganic oxide fine particles (B) containing colloidal silica as a main component are represented by the following general formula (1). It contains an inorganic oxide-acrylic resin composite (α) formed by bonding via a site and a photocationic polymerization initiator (β).
[Chemical formula 4]
—O—Si—R ¹ —NHCOO— (1)
In [the formula (1), R ¹ is a linear or branched alkylene group having 1 to 10 carbon atoms. ]

<< Specific acrylic resin (A) >>
The specific acrylic resin (A) used in the present invention contains an acrylic group containing a fluorine atom-containing structure site (hereinafter sometimes referred to as “fluorine-containing group”) and an epoxy group in its molecular chain. It is preferable to have a fluorine-containing group and an epoxy group in the side chain of the polymer chain from the viewpoint of easy production of the polymer, and exist as a group different from the fluorine-containing group and the epoxy group It is preferable to do.

Examples of the fluorine atom-containing structure moiety include fluoroalkyl structures such as — (CF ₂ ) _n CF ₃ , — (CF ₂ ) _n CHF ₂ , — (CF ₂ ) _n CHCF ₂ (all n are integers of 0 or more). ).

  The higher the proportion of the fluorine atom-containing structural site in the acrylic resin (A) in the acrylic resin (A), the lower the refractive index of the low refractive index layer made of the coating film can be reduced. The antireflection effect when the body is made can be increased, but on the other hand, increasing the ratio too much, for example, reduces the ratio of epoxy groups in the acrylic resin (A), and irradiates with active energy rays. This is not preferable because the density of cross-linking points sometimes formed is lowered. That is, there is a preferred range for the ratio of the fluorine atom-containing structural portion and the ratio of the epoxy group in the acrylic resin (A).

  If the fluorine atom-containing compound is not copolymerized in addition to the fluorine atom-containing (meth) acrylic acid ester monomer (a1) described below, the ratio of the fluorine atom-containing structural sites is quantitative analysis of the elements contained in the acrylic resin (A). And the weight ratio of fluorine atoms in the acrylic resin (A) can be estimated. Further, even if quantitative analysis of the contained elements is not performed, if the remaining unreacted monomer is reduced to less than about 1% by weight of the charged monomer amount at the time of the polymerization reaction for obtaining the acrylic resin (A), it is charged. Assuming that almost all monomers constitute the acrylic resin (A), it can be estimated from the weight ratio of the charged monomers. Further, it is preferable to perform polymerization so that the remaining unreacted monomer is reduced from the viewpoint of efficiently using the charged monomer and from the viewpoint that it is not necessary to separate and remove the unreacted monomer after the completion of the polymerization reaction.

The residual amount of the unreacted monomer is measured and quantified as follows, for example. That is, the acrylic resin (A) solution is analyzed by GC / MS, the mass of the residual monomer in the acrylic resin (A) is obtained from a calibration curve obtained in advance, and is obtained as a weight ratio with respect to the charged monomer mass. . The GC / MS conditions are as follows.
AS part condition: 7683 Series manufactured by Agilent Technologies. Inject amount 1.0μL
GC section condition: 6890N Network GC System manufactured by Agilent Technologies. Column DB-17MS (Crosslinked Methyl Siloxane) 29.3 m (l) × 0.25 mm (id) × 0.25 μm (d), flow rate 1.0 mL / min. Column temperature 40 ° C. × 5 minutes → 220 ° C. × 10 minutes, heating rate 10 ° C./min. Inlet 220 ° C. Carrier gas He. Split ratio 30: 1.
MS part condition: 5973inert MassSelective Detector manufactured by Agilent Technologies. Mass range 10-600. Ion source temperature 230 ° C. Quadrupole temperature 150 ° C. The number of scans is 2.52 / second.

  The ratio of the epoxy group in the acrylic resin (A) can be estimated as a molar ratio by obtaining the epoxy equivalent of the acrylic resin (A) according to JIS K7236. Similarly to the determination of the weight ratio of fluorine atoms, if polymerization is performed so that the remaining unreacted monomer is reduced, it can be estimated from the weight ratio of charged monomers.

  The ratio of the fluorine atom-containing structure site in the acrylic resin (A) (hereinafter sometimes referred to as “fluorine-containing ratio”) and the ratio of epoxy groups (hereinafter sometimes referred to as “epoxy-containing ratio”), Further, to evaluate the ratio, generally, the former is obtained as the weight ratio of the elements in the acrylic resin (A), and the latter is obtained as the weight ratio of the functional groups in the acrylic resin (A). Since an appropriate index cannot be shown, preferred ranges can be shown as “fluorine-containing ratio” and “epoxy-containing ratio”, respectively.

  That is, the “fluorine-containing ratio” is preferably 10 to 30% by weight and more preferably 15 to 25% by weight as the weight ratio of fluorine atoms in the acrylic resin (A).

  Further, the “epoxy-containing ratio” is preferably a value estimated from the amount of JIS K7236 or the remaining unreacted monomer and the charged monomer weight ratio as the epoxy equivalent of the acrylic resin (A), preferably 650 to 3900, and 780 to 1950. Is more preferable.

  The acrylic resin (A) of the present invention is a copolymer of copolymer components containing a fluorine atom-containing (meth) acrylic acid ester monomer (a1) and an epoxy group-containing (meth) acrylic acid ester monomer (a2). In order to provide the structural moiety represented by the general formula (1) at this time, a hydroxyl group-containing (meth) acrylic acid ester monomer (a3) is further added to the copolymerization component [ It is particularly preferable to add it as I] for copolymerization.

<Fluorine atom-containing (meth) acrylic acid ester monomer (a1)>
As the fluorine atom-containing (meth) acrylic acid ester monomer (a1), a (meth) acrylic acid ester monomer containing a fluorine atom in the molecule may be used, and in particular, a (meth) having a fluoroalkyl group. It is preferable to use an acrylic ester.

Examples of the fluoroalkyl group include —COOCH ₂ (CF ₂ ) _n CF ₃ , —COOCH ₂ CH ₂ (CF ₂ ) _n CF ₃ , —COOCH ₂ (CF ₂ ) _n CHF ₂ , —COOCH ₂ CH ₂ ( CF ₂ ) _n CHCF _{2 and the} like (all n are integers of 0 or more), and these can be used alone or in combination of two or more. Preferably, the fluoroalkyl group has 0 to 12 (preferably 0 to 10) carbon atoms (n in the above) from the viewpoint of easy availability and easy effect. Specifically, CF ₃ CH ₂ - trade name of Kyoeisha Chemical Co., Ltd. having a group "M-3F", CF ₃ CF ₂ CH ₂ - trade name manufactured by Daikin Industries, Ltd. having a group "M-1210" , A product name “M-1420” manufactured by Daikin Industries, Ltd. having a F (CF ₂ ) ₄ CH ₂ CH ₂ — group, and a product manufactured by Daikin Industries, Ltd. having an F (CF ₂ ) ₆ CH ₂ CH ₂ — group. Name “M-1620” and the like.

  The content of the fluorine atom-containing (meth) acrylic acid ester monomer (a1) is preferably 40 to 80% by weight, particularly preferably 50 to 70% by weight, based on the entire copolymerization component [I]. If the content of the fluorine atom-containing (meth) acrylic acid ester monomer (a1) is too large, the cost becomes high, and the effect of improving the scratch resistance on the film obtained by photocuring the active energy ray-curable resin composition There is a tendency that it is difficult to demonstrate. Moreover, when there is too little content, the tendency for achievement of the desired low refractive index reduction in the film | membrane obtained by photocuring an active energy ray curable resin composition will be seen.

<Epoxy group-containing (meth) acrylic acid ester monomer (a2)>
The epoxy group-containing (meth) acrylic acid ester monomer (a2) may be a (meth) acrylic acid ester having an epoxy group as part of the ester group, and the epoxy group has an alicyclic epoxy structure. What it has is preferable because the reaction at the time of photocuring the active energy ray-curable resin composition is fast. For example, glycidyl (meth) acrylate, 3,4-epoxycyclohexylmethyl (meth) acrylate, and the like can be mentioned. Specifically, Acryester G (glycidyl methacrylate) manufactured by Mitsubishi Rayon Co., Ltd., manufactured by Daicel Chemical Industries, Ltd. Cyclomer M100 (3,4-epoxycyclohexylmethyl methacrylate). These can be used alone or in combination.

  The content of the epoxy group-containing (meth) acrylic acid ester monomer (a2) is preferably 5 to 30% by weight, particularly preferably 10 to 25% by weight, based on the entire copolymerization component [I]. If the content of the epoxy group-containing (meth) acrylic acid ester monomer (a2) is too large, it is difficult to achieve a desired low refractive index in a film obtained by photocuring the active energy ray-curable resin composition. If the content is too small, it tends to be difficult to exert the effect of improving the scratch resistance on the film obtained by photocuring the active energy ray-curable resin composition.

<Hydroxyl group-containing (meth) acrylic acid ester monomer (a3)>
In the present invention, a hydroxyl group can be contained in the acrylic resin (A) by copolymerizing the hydroxyl group-containing (meth) acrylic acid ester monomer (a3). A urethane bond in the binding site represented by the formula (1) will be formed.

  Examples of the hydroxyl group-containing (meth) acrylic acid ester monomer (a3) include 2-hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, and the like. These may be used alone or in combination of two or more. Among these, it is particularly preferable to use 2-hydroxyethyl (meth) acrylate because it is easily available and has good affinity with silica.

  The content of the hydroxyl group-containing (meth) acrylic acid ester monomer (a3) is preferably 5 to 30% by weight, particularly preferably 10 to 25% by weight, based on the entire copolymerization component [I]. If the content of the hydroxyl group-containing (meth) acrylic acid ester monomer (a3) is too large, unreacted hydroxyl groups increase in the resin composition, so that the active energy ray-curable resin composition is photocured. Achieving a desired low refractive index in the resulting film tends to be difficult, and if the content is too small, the effect of improving the scratch resistance on the film obtained by photocuring the active energy ray-curable resin composition It tends to be difficult to demonstrate.

<Other monomer components>
Furthermore, other than the fluorine atom-containing (meth) acrylic acid ester monomer (a1), epoxy group-containing (meth) acrylic acid ester monomer (a2), and hydroxyl group-containing (meth) acrylic acid ester monomer (a3) Other monomer components can be used. For example, the alkyl (meth) acrylic acid ester monomer (a4) may be copolymerized from the viewpoint of improving copolymerization and adhesion.

  Examples of the alkyl (meth) acrylate monomer (a4) include methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, iso-butyl (meth) acrylate, tert-butyl ( (Meth) acrylate, n-propyl (meth) acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, iso-octyl acrylate, isodecyl (meth) acrylate, lauryl (meth) ) Acrylate, cetyl (meth) acrylate, stearyl (meth) acrylate, iso-stearyl (meth) acrylate and other (meth) acrylic acid alkyl esters; cyclohexyl (meth) acrylate, isobornyl (meth) a Alicyclic such Relate (meth) acrylic acid ester. In the case of the above (meth) acrylic acid alkyl ester, the alkyl group preferably has 1 to 20 carbon atoms, particularly preferably 1 to 12, more preferably 1 to 8, and particularly preferably 4 to 8. These can be used alone or in combination of two or more. Among these, methyl (meth) acrylate is preferably used because it is easily available and has good copolymerizability.

  The content of the alkyl (meth) acrylate monomer (a4) is preferably 10 to 30% by weight, particularly preferably 15 to 25% by weight, based on the entire copolymerization component [I].

<Method for Producing Specific Acrylic Resin (A)>
The specific acrylic resin (A) includes the fluorine atom-containing (meth) acrylic acid ester monomer (a1), the epoxy group-containing (meth) acrylic acid ester monomer (a2), and the hydroxyl group-containing (meth) acrylic acid ester. It can be produced by copolymerizing the monomer (a3) and, if necessary, the alkyl (meth) acrylate monomer (a4). Examples of the copolymerization method include solution radical polymerization, suspension polymerization, bulk polymerization, and emulsion polymerization. Among them, a copolymerization method by solution radical polymerization is preferable from the viewpoint of easy control of the reaction. This solution radical polymerization method is carried out, for example, by mixing or dropping each of the monomer components (a1) to (a4) and the polymerization initiator in a solvent and heating and stirring. Although the said heating conditions are suitably set by the solvent to be used, the kind of monomer component, and the kind of polymerization initiator, Usually, 50-150 degreeC and reaction time are 2 to 20 hours.

  As the solvent, an acrylic resin (A) can be dissolved and mixed with inorganic oxide fine particles (B) mainly composed of colloidal silica, which will be described later, and can react with isocyanate groups such as alcohol and amine. It is preferable to use one having no group. That is, when a solvent having a functional group that reacts with an isocyanate group such as alcohol or amine is used as a solvent, an acrylic resin (A) and inorganic oxide fine particles (B) containing colloidal silica as main components are used in a subsequent step. When bonding is attempted through the bonding site represented by the general formula (1), not only the acrylic resin (A) and the inorganic oxide fine particles (B) mainly composed of colloidal silica are bonded but also a solvent. And inorganic oxide fine particles (B) mainly composed of colloidal silica are bonded, and a large number of particles not bonded to the acrylic resin (A) are not preferable. For this reason, for example, esters such as 1-methoxy-2-procelacetate, ethyl acetate and butyl acetate, ethers such as tetrahydrofuran and 1,4-dioxane, and the like are used. These may be used alone or in combination of two or more.

  As the polymerization initiator, a normal radical polymerization initiator can be used. For example, azo polymerization initiators such as azobisisobutyronitrile and azobisdimethylvaleronitrile, benzoyl peroxide, lauryl peroxide, Peroxide-based polymerization initiators such as -t-butyl peroxide and cumene hydroxy peroxide can be used.

  In the polymerization, a chain transfer agent can be used. Examples of the chain transfer agent include mercaptans such as octyl mercaptan and lauryl mercaptan. Moreover, when using the said chain transfer agent, the usage-amount is preferably 1 to 10 weight% with respect to the whole acrylic resin (A), Most preferably, it is 1 to 5 weight%.

  The specific acrylic resin (A) thus obtained preferably has a weight average molecular weight of 10,000 to 100,000, more preferably 20,000 to 50,000. The weight average molecular weight can be controlled by the amount of polymerization initiator used and the polymerization temperature conditions, and can be further finely adjusted by blending a chain transfer agent if necessary. When the weight average molecular weight is too large, the viscosity of the active energy ray-curable resin composition tends to be high and it tends to be difficult to apply to a film thickness of less than 1 μm. When the weight average molecular weight is too small, When formed on the antireflection film, it tends to be difficult to maintain the shape of the coating film.

In addition, the said weight average molecular weight is a weight average molecular weight by standard polystyrene molecular weight conversion, gel permeation chromatography, specifically, a weight average molecular weight is by standard polystyrene molecular weight conversion, and is a high performance liquid chromatography (Japan “Waters 2695 (main body)” and “Waters 2414 (detector)”, columns: Shodex GPC KF-806L (exclusion molecular weight: 2 × 10 ⁷ , separation range: 100 to 2 × 10 ⁷ , theory) It is measured by using three series of stages: 10,000 stages / line, filler material: styrene-divinylbenzene copolymer, filler particle diameter: 10 μm.

<< Inorganic oxide fine particles (B) mainly composed of colloidal silica >>
The inorganic oxide fine particles (B) containing colloidal silica as a main component (hereinafter sometimes abbreviated as “inorganic fine particles (B)”) are neutralized with acid using water glass as a raw material, or alkyl silicates are alkalinized. For example, a commercially available product can be easily obtained.

  The inorganic fine particles (B) are not particularly defined as long as they have colloidal silica as a main component. “Containing colloidal silica as a main component” means that the content is usually 50% by weight or more and includes only colloidal silica.

  Examples of the shape of the inorganic fine particles (B) include a spherical shape, a hollow shape, a porous shape, a rod shape, a fiber shape or a plate shape, and an indefinite shape, and a spherical shape is more preferable. The term “spherical” as used in the present invention is intended to include not only exact spheres but also substantially spherical ones.

  In the present invention, in the form of an organosilica sol dispersed in an organic solvent, it is easy to mix with the specific acrylic resin (A), and it is easy to obtain a uniform active energy ray-curable resin composition. It is preferable to use colloidal silica. Examples of the organic solvent include 2-propanol, 1-methoxy-2-propanol, 2-propanone, and the like. Further, as the inorganic oxide fine particles (B), those having a hollow structure are preferable because the refractive index can be further lowered.

And from a viewpoint of providing transparency of the antireflection film having a low refractive index layer finally obtained, the average particle diameter of the inorganic oxide fine particles (B) is preferably 10 to 100 nm, particularly preferably 10 to 50 nm. It is. If the average particle size is too large, secondary aggregation tends to occur and the transparency tends to decrease, and if it is too small, mechanical properties tend to decrease.
The average particle size is calculated from the average specific surface area of the particles determined by the BET method in accordance with JIS R 1626 and the true specific gravity of the particles.

  Specifically, as the inorganic oxide fine particles (B) mainly composed of colloidal silica, a product name “IPA-ST” (2-propanol dispersion, average particle diameter of 10 to 15 nm) manufactured by Nissan Chemical Industries, Ltd. The name “PGM-ST” (1-methoxy-2-propanol dispersion, average particle size 10 to 15 nm), the trade name “MEK-ST” (2-propanone dispersion, average particle size 10 to 15 nm), and the like. Moreover, as an example of a commercial product in which silica has a hollow structure, a trade name “Thruria” manufactured by JGC Catalysts & Chemicals Co., Ltd. can be cited.

  Furthermore, as the inorganic oxide fine particles (B) mainly composed of colloidal silica, the surface of the inorganic oxide fine particles (B) is modified with a silane coupling agent for the purpose of improving the dispersion stability of the inorganic oxide fine particles. May be.

  Examples of the silane coupling agent include methyltrimethoxysilane, dimethyldiethoxysilane, and phenyltriethoxysilane. These may be used alone or in combination of two or more. As the silane coupling agent, specifically, trade name “KBM-13” (methyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., trade name “KBE-22” (dimethyldiethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd. ), Trade name “KBE-103” (phenyltriethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., and the like.

The amount of the silane coupling agent used is preferably 5 × 10 ^{−1 to} 10 mmol / g of silica, particularly preferably relative to the silica in the solid content of the inorganic oxide fine particles (B) mainly composed of the colloidal silica. Is 1-4 mmol / g of silica. If the amount used is too large, the cost tends to increase. If the amount used is too small, the photocationic polymerization initiator (β) described later approaches the silica surface in the active energy ray-curable resin composition. As a result, the pot life tends to decrease.

  As a method for modifying the surface of the inorganic oxide fine particles (B) using the silane coupling agent, for example, the silane coupling agent is added to the organosilica sol together with an amount of water capable of hydrolyzing the alkoxy group of the silane coupling agent, A method of modifying the surface of the fine particles by blending the mixture with an acid or a base as a catalyst, if necessary, and stirring at room temperature (about 25 ± 10 ° C.) to 70 ° C. for 30 minutes to several hours can be mentioned.

  The content of the inorganic oxide fine particles (B) mainly composed of colloidal silica is preferably 25 to 100 parts by weight, particularly preferably 40 to 70 parts per 100 parts by weight of the specific acrylic resin (A). Parts by weight. If the content is too high, it tends to be difficult to maintain the shape of the coating film when formed on the antireflection film. If the content is too low, the scratch resistance of the resulting antireflection film is reduced. There is a tendency to

<< Inorganic oxide-acrylic resin composite (α) >>
In the present invention, an acrylic resin (A) containing a hydroxyl group and containing a fluorine atom-containing structural site and an epoxy group (hereinafter, sometimes referred to as “specific acrylic resin (A)”). And an inorganic oxide-acrylic resin composite (α) in which inorganic oxide fine particles (B) mainly composed of colloidal silica are bonded via a bonding site represented by the following general formula (1) By using it, a coating agent excellent in pot life can be obtained, and an antireflection film having good scratch resistance and having a low refractive index layer by curing the coating film formed using this coating agent with ultraviolet rays Can be obtained.
[Chemical formula 5]
—O—Si—R ¹ —NHCOO— (1)
In [the formula (1), R ¹ is a linear or branched alkylene group having 1 to 10 carbon atoms. ]

In the above formula (1), R ¹ is a linear or branched alkylene group having 1 to 10 carbon atoms, and the alkylene group preferably has 1 to 4 carbon atoms, specifically a methyl group or an ethyl group. N-propyl group, iso-propyl group, n-butyl group and tert-butyl group are preferable.

  As a method for producing the binding site represented by the above general formula (1) obtained by binding the specific acrylic resin (A) and the inorganic oxide fine particles (B) containing colloidal silica as a main component, 1 Examples include a method using a silicon compound (E) having both a hydrolyzable alkoxy group and an isocyanate group capable of reacting with a hydroxyl group in the molecule (hereinafter sometimes referred to as “silicon compound (E)”). . An example of the silicon compound (E) is 3-isocyanatopropyltriethoxysilane. Specifically, the brand name “KBE-9007” manufactured by Shin-Etsu Chemical Co., Ltd. and the like can be mentioned. This silicon compound (E) is produced by allowing the fine particles (B) to coexist when the isocyanate groups react with the hydroxyl groups of the specific acrylic resin (A) and the alkoxysilyl groups are hydrolyzed. It is also combined with (B).

<Method for producing inorganic oxide-acrylic resin composite (α)>
As a manufacturing method of the said inorganic oxide-acrylic-type resin composite ((alpha)), when the mixing order of a mixing | blending component was considered, [1] making specific acrylic resin (A) and a silicon compound (E) react. Then, a method of adding the inorganic oxide fine particles (B) mainly composed of colloidal silica, [2] After reacting the inorganic oxide fine particles (B) mainly composed of colloidal silica and the silicon compound (E), The method of adding specific acrylic resin (A) is mention | raise | lifted.

  In the said manufacturing method, when what reacts with the isocyanate group of silicon compound (E), such as alcohol and an amine, is contained in the solvent used by specific acrylic resin (A), specific acrylic resin ( This is not preferable because the initial purpose of combining A) with inorganic oxide fine particles (B) containing colloidal silica as a main component cannot be achieved.

  However, in the case of the production method [2] in which the inorganic oxide fine particles (B) mainly containing colloidal silica and the silicon compound (E) are reacted first, the inorganic oxide fine particles (B) mainly containing colloidal silica. Since the isocyanate group of the silicon compound (E) may be affected during the hydrolysis reaction, the specific acrylic resin (A) and the silicon compound (E) are reacted first, The above production method [1] in which the inorganic oxide fine particles (B) mainly composed of colloidal silica are added is even more preferable.

  In addition, when only the solvent of the inorganic oxide fine particles (B) containing colloidal silica as a main component contains alcohol, amine, or the like that reacts with the isocyanate group of the silicon compound (E), a specific acrylic is first used. What is necessary is just to make it react with inorganic oxide microparticles | fine-particles (B) which have colloidal silica as a main component, after making a system resin (A) and a silicon compound (E) react.

<[1] Method for producing inorganic oxide-acrylic resin composite (α)>
First, [1] a specific acrylic resin (A) and a silicon compound (E) are reacted, and then inorganic oxide fine particles (B) containing colloidal silica as a main component are added, whereby an inorganic oxide-acrylic system is added. A method for producing the resin composite (α) will be described.

  The manufacturing method [1] of the inorganic oxide-acrylic resin composite (α) is performed as follows. First, a copolymer containing a fluorine atom-containing (meth) acrylic acid ester monomer (a1), an epoxy group-containing (meth) acrylic acid ester monomer (a2) and a hydroxyl group-containing (meth) acrylic acid ester monomer (a3) By copolymerizing component [I], a specific acrylic resin (A) containing a fluorine atom-containing structural site, an epoxy group and a hydroxyl group is produced. Next, the specific acrylic resin (A) is blended with a silicon compound (E) having both a hydrolyzable alkoxy group and a hydroxyl group-reactive isocyanate group in one molecule, and further if necessary. The catalyst is blended, and both are reacted under reaction conditions of room temperature (about 25 ± 10 ° C.) to about 80 ° C. until the isocyanate group derived from the component (E) is no longer detected.

  The amount of the silicon compound (E) used is appropriately set depending on the molecular weight of the specific acrylic resin (A) and how much the hydroxyl group is to be reacted, but the molecule of the specific acrylic resin (A). It is preferable to set it to such an extent that about 1 to 10 of the hydroxyl groups present per chain are reacted. For example, if it is estimated that about 30 hydroxyl groups are present in one molecular chain, judging from the molecular weight and the amount of the hydroxyl group-containing (meth) acrylic acid ester monomer (a3) charged, ) It is set to use about 1/30 to 1/3 mole of the acrylate monomer (a3).

  The reaction time at this time is appropriately set depending on whether or not the catalyst is used and the reaction temperature, but is usually 0.5 to 24 hours. Moreover, a well-known urethanization catalyst can be used as said catalyst, For example, a dialkyl dialkoxy tin etc. are mention | raise | lifted. And the usage-amount of the said catalyst is the range of 50-1,000 ppm with respect to the whole reaction system normally in conversion of the metal salt of a catalyst.

  Next, after the reaction between the specific acrylic resin (A) and the silicon compound (E) is completed, the reaction product is cooled to near room temperature, and then the reaction product is mixed with inorganic oxide fine particles (B) containing colloidal silica as a main component. (For example, in an organosilica gel state) and water in an amount sufficient to hydrolyze the alkoxy group in the silicon compound (E), and further, if necessary, a catalyst, and room temperature (about 25 ± 10 ° C.) The reaction between the silicon compound (E) and the inorganic oxide fine particles (B) in the reaction product is performed by stirring and mixing under a reaction condition of about -80 ° C., and a specific acrylic resin (A) And an inorganic oxide fine particle (B) are bonded through the bonding site represented by the general formula (1) to prepare an inorganic oxide-acrylic resin composite (α).

  The reaction time in the reaction between the silicon compound (E) and the inorganic oxide fine particles (B) is appropriately set depending on whether or not a catalyst is used and the reaction temperature, but is usually 0.5 to 24 hours. Moreover, as said catalyst, a well-known thing can be used, For example, an acid, a base, or a metal complex is mention | raise | lifted. Specific examples include acidic catalysts such as acetic acid and propionic acid, basic catalysts such as sodium hydroxide, potassium hydroxide, sodium methoxide, potassium methoxide and triethylamine, and metal complexes such as aluminum acetylacetonate. Can do. The amount of the catalyst used is usually 0.1 to 5 parts by weight, preferably 0.5 to 5 parts by weight with respect to 100 parts by weight of the total amount of the silicon compound (E) and the inorganic oxide fine particles (B). Set to

<[2] Manufacturing method of inorganic oxide-acrylic resin composite (α)>
Next, [2] inorganic oxide fine particles (B) containing colloidal silica as a main component and a silicon compound (E) are reacted, and then a specific acrylic resin (A) is added to thereby add an inorganic oxide-acrylic type. A method for producing the resin composite (α) will be described.

  The manufacturing method [2] of the inorganic oxide-acrylic resin composite (α) is performed as follows. That is, a silicon compound (E) having both a hydrolyzable alkoxy group and a hydroxyl group-reactive isocyanate group in one molecule, and inorganic oxide fine particles (B) mainly composed of colloidal silica (for example, organo Silica gel state) and an amount of water sufficient to hydrolyze the alkoxy group in the silicon compound (E) are blended, and a catalyst is blended if necessary, and room temperature (about 25 ± 10 ° C.) to about 80 ° C. By stirring and mixing under the reaction conditions, the silicon compound (E) and the inorganic oxide fine particles (B) are reacted to produce a reaction product (B-E).

  The amount of the silicon compound (E) used is appropriately set depending on how much the hydroxyl group in the specific acrylic resin (A) is to be reacted, as in the above production method [1]. It is preferable to set it to such an extent that about 1 to 10 of the hydroxyl groups present per molecular chain (A) to be used are reacted. For example, if it is estimated that about 30 hydroxyl groups are present in one molecular chain, judging from the molecular weight and the amount of the hydroxyl group-containing (meth) acrylic acid ester monomer (a3) charged, ) It is set to use about 1/30 to 1/3 mole of the acrylate monomer (a3).

  And although the said reaction time is suitably set by the presence or absence of use of a catalyst, and reaction temperature, it is 0.5 to 24 hours normally. Moreover, as said catalyst, a well-known thing can be used, For example, an acid, a base, or a metal complex is mention | raise | lifted. Specific examples include acidic catalysts such as acetic acid and propionic acid, basic catalysts such as sodium hydroxide, potassium hydroxide, sodium methoxide, potassium methoxide and triethylamine, and metal complexes such as aluminum acetylacetonate. Can do. The amount of the catalyst used is usually 0.1 to 5 parts by weight, preferably 0.5 to 5 parts by weight with respect to 100 parts by weight of the total amount of the silicon compound (E) and the inorganic oxide fine particles (B). Set to

  On the other hand, a copolymer containing a fluorine atom-containing (meth) acrylic acid ester monomer (a1), an epoxy group-containing (meth) acrylic acid ester monomer (a2) and a hydroxyl group-containing (meth) acrylic acid ester monomer (a3). By copolymerizing the polymerization component [I], a specific acrylic resin (A) containing a fluorine atom-containing structural site, an epoxy group and a hydroxyl group is produced. Next, after cooling the reaction product (BE) to near room temperature, the reaction product is mixed with the specific acrylic resin (A) solution, and a catalyst is blended as necessary. The mixture between the silicon compound (E) and the specific acrylic resin (A) in the reaction product (BE) is obtained by stirring and mixing under reaction conditions of room temperature (about 25 ± 10 ° C.) to about 80 ° C. Inorganic oxide-acrylic resin in which a specific acrylic resin (A) and inorganic oxide fine particles (B) are bonded via the bonding site represented by the general formula (1) A composite (α) is prepared.

  The reaction time in the reaction between the silicon compound (E) and the specific acrylic resin (A) in the reaction product (B-E) is appropriately set depending on whether or not a catalyst is used and the reaction temperature. .5-24 hours. Moreover, a well-known urethanization catalyst can be used as said catalyst, For example, a dialkyl dialkoxy tin etc. are mention | raise | lifted. And the usage-amount of the said catalyst is the range of 50-1,000 ppm with respect to the whole reaction system normally in conversion of the metal salt of a catalyst.

  In the said manufacturing method, the compounding ratio of specific acrylic resin (A) and the inorganic oxide fine particle (B) which has colloidal silica as a main component is 100 weight part of solid content of specific acrylic resin (A). The solid content of the inorganic oxide fine particles (B) mainly composed of colloidal silica is preferably 25 to 100 parts by weight, particularly preferably 40 to 70 parts by weight. When the blending ratio of the inorganic oxide fine particles (B) is too large, it tends to be difficult to maintain the shape of the coating film when formed on the antireflection film. Moreover, when there are too few compounding ratios of inorganic oxide microparticles | fine-particles (B), the tendency for the abrasion resistance of the antireflection film formed to fall will be seen.

  And specific acrylic resin (A) couple | bonded through the coupling | bond part shown by the said General formula (1) of the inorganic oxide-acrylic-resin composite ((alpha)) obtained with the said manufacturing method The degree of bonding of the inorganic oxide fine particles (B) can be appropriately adjusted depending on the amount of the silicon compound (E) used. The minimum amount of the bond is such that, on average, it reacts with one of the hydroxyl groups present in one molecular chain of the specific acrylic resin (A), and the maximum amount of the bond is the above molecule. Although it is a grade which reacts with all the hydroxyl groups which exist in a chain | strand, Preferably several to about 10 are an upper limit. If the degree of bonding is too small, there is a concern that there are many specific acrylic resins (A) to which the silicon compound (E) is not bonded, and there is a tendency for the pot life and scratch resistance to be adversely affected. Also, if the degree of bonding is too high, the silicon compound (E) becomes excessive and is not preferred in terms of cost, and the hydroxyl group also plays a role in maintaining affinity with the inorganic oxide fine particles, but its ability to be reduced. It is not preferable.

  The degree of bonding between the specific acrylic resin (A) and the inorganic oxide fine particles (B) is preferably averaged out of the hydroxyl groups present in one molecular chain of the specific acrylic resin (A). And several hydroxyl groups react with the silicon compound (E). For example, the average degree of polymerization of the specific acrylic resin (A) is 100, and the amount of the hydroxyl group-containing (meth) acrylic acid ester monomer (a3) used is all for producing the specific acrylic resin (A). When it is 25 mol% in the monomer, it is estimated that about 25 hydroxyl groups exist on average in one molecular chain of the specific acrylic resin (A). Accordingly, the amount of the silicon compound (E) used is 1 mol% with respect to the hydroxyl group-containing (meth) acrylic acid ester monomer (a3) in the minimum amount, and the hydroxyl group-containing (meth) acrylic acid ester monomer (a) in the maximum amount. Although it is estimated to be 25 mol% with respect to a3), it is preferably 1 to 5 mol% with respect to the hydroxyl group-containing (meth) acrylic acid ester monomer (a3). At this time, since it is presumed that hydroxyl groups are present on average in the molecular chain in the specific acrylic resin (A), the silicon compound (E) is also averaged in the molecular chain of the specific acrylic resin (A). It is assumed that it reacts. That is, the silicon compound (E) may react with a hydroxyl group that may be present at the end of the molecular chain of the specific acrylic resin (A), but the center of the molecular chain of the specific acrylic resin (A). When the active energy ray-curable resin composition is presumed to have a high ratio of reacting with hydroxyl groups present in a larger amount, inorganic oxide fine particles (A) having a specific acrylic resin (A) as a main component of colloidal silica ( B) is effectively covered. Therefore, when the hydroxyl group present more in the center of the molecular chain of the specific acrylic resin (A) reacts with the silicon compound (E), the specific acrylic resin (A) extending on both sides of the reaction point The molecular chain also covers the inorganic oxide fine particles (B), and the specific acrylic resin (A) is more than the case where the hydroxyl group present in the molecular chain of the specific acrylic resin (A) exists only at the terminal portion. It can be said that the molecular chain can be used effectively.

  In addition, when many hydroxyl groups existing in the molecular chain in the specific acrylic resin (A) are reacted with the silicon compound (E), the silicon compound (B) can be bonded at many reaction points. The purpose of covering the inorganic oxide fine particles (B) is, on average, 1 to 10 hydroxyl groups among the hydroxyl groups in which the silicon compound (E) is present in one molecular chain of the specific acrylic resin (A), preferably Is achieved only to the extent that it reacts with several hydroxyl groups. Therefore, even if the silicon compound (E) is used in an excessive amount more than necessary, the cost is increased and it is not economical.

Thus, an acrylic resin (A) containing a hydroxyl group and containing a fluorine atom-containing structural site and an epoxy group, and inorganic oxide fine particles (B) containing colloidal silica as a main component are: 1 An inorganic oxide-acrylic resin composite (α) formed by bonding via a bonding site represented by the general formula (1) derived from the silicon compound (E) having both an alkoxy group and an isocyanate group in the molecule Can be manufactured.

<< Photocationic polymerization initiator (β) >>
The photocationic polymerization initiator (β) has a catalytic action for initiating a cationic polymerization reaction upon irradiation with light, and generates a cationic polymerization catalyst such as a Lewis acid by irradiating ultraviolet rays or the like. Can be used. For example, diazonium salt, sulfonium salt, iodonium salt and the like can be mentioned. Specifically, diazonium salts such as benzenediazonium hexafluoroantimonate, benzenediazonium hexafluorophosphate, benzenediazonium hexafluoroborate, triphenylsulfonium hexafluoroantimonate, triphenylsulfonium hexafluorophosphate, triphenylsulfonium hexafluoroborate, 4,4'-bis [bis (2-hydroxyethoxyphenyl) sulfonio] phenyl sulfide bishexafluorophosphate, sulfonium salts such as diphenyl-4-thiophenoxyphenylsulfonium hexafluorophosphate, diphenyliodonium hexafluoroantimonate, diphenyliodonium hexa Fluorophosphate, bis (4-tert-butylphenyl) Iodonium hexafluorophosphate, bis (4-t- butylphenyl) iodonium salts such as iodonium hexafluoroantimonate and the like. Of these, iodonium salts are most often used. These may be used alone or in combination of two or more.

  Specific examples of the photocationic polymerization initiator (β) include a product name “Adekaoptomer SP-150” (triallylsulfonium hexafluorophosphate) manufactured by ADEKA, and a product name “Adekaoptomer SP-170”. (Triallylsulfonium hexafluoroantimonate) and the like.

  The amount of the cationic photopolymerization initiator (β) used is preferably 0.1 to 10 parts by weight, particularly preferably 1 to 5 parts by weight with respect to 100 parts by weight of the inorganic oxide-acrylic resin composite (α). Part. If the amount of the cationic photopolymerization initiator (β) used is too large, it is not economical, and the cationic photopolymerization initiator (β) is present on the surface of the inorganic oxide fine particles (B) in the active energy ray-curable resin composition. It tends to approach and the pot life tends to decrease. Moreover, when there is too little usage-amount, the tendency for the abrasion resistance of the antireflection film formed to fall will be seen.

<< Hydrolyzed product of epoxy group-containing alkoxysilane (C) >>
To the active energy ray-curable resin composition of the present invention, an epoxy group-containing alkoxysilane hydrolyzate (C) may be added for the purpose of improving the stability of the resin composition and improving the scratch resistance. The epoxy group-containing alkoxysilane hydrolyzate (C) is obtained by hydrolytic condensation of an epoxy group-containing alkoxysilane with an acid or a base. The epoxy group-containing alkoxysilane used as a raw material may be a compound having an epoxy group and an alkoxysilyl group, such as 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 2 -(3,4-epoxycyclohexyl) ethyltrimethoxysilane or the like is preferably used. These may be used alone or in combination of two or more. Specifically, trade name “KBM-403” (3-glycidoxypropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., trade name “KBE-402” (3-glycidoxypropyl) manufactured by Shin-Etsu Chemical Co., Ltd. Methyl diethoxysilane), trade name “KBM-303” [2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane] manufactured by Shin-Etsu Chemical Co., Ltd. and the like can be mentioned.

  The amount of the epoxy group-containing alkoxysilane hydrolyzate (C) is preferably 50 to 250 parts by weight, particularly preferably 80 to 200 parts by weight, based on 100 parts by weight of the specific acrylic resin (A). is there. If the amount is too large, it tends to be difficult to maintain the shape of the coating film when formed on the antireflection film. If the amount is too small, the formed antireflection film has scratch resistance. There is a tendency to decrease.

<< Sensitizer (F) >>
Furthermore, in the active energy ray-curable resin composition of the present invention, a sensitizer (F) that promotes cationic polymerization can be used in combination with the photocationic polymerization initiator (β) as necessary. Examples include anthracene, 9,10-dimethoxyanthracene, 2-ethyl-9,10-dimethoxyanthracene, 2-ethyl-9,10-di (methoxyethoxy) anthracene. These may be used alone or in combination of two or more. Among these, 2-ethyl-9,10-di (methoxyethoxy) anthracene is preferably used from the viewpoint of the compatibility of the resin composition.

  The amount of the sensitizer (F) used is preferably 1 to 100 parts by weight, particularly preferably 5 to 50 parts by weight, with respect to 100 parts by weight of the cationic photopolymerization initiator (β).

《Other additives》
In the active energy ray-curable resin composition of the present invention, a leveling agent, an antifoaming agent, an ultraviolet absorber, a light stabilizer and the like can be appropriately blended as necessary in addition to the above-described blending components.

  Examples of the leveling agent include fluorine compounds and silicone compounds, and examples of the ultraviolet absorber include benzotriazole compounds, benzophenone compounds, and triazine compounds. Examples of the light stabilizer include hindered compounds.

  Furthermore, an antioxidant, a flame retardant, an antistatic agent, a stabilizer, a reinforcing agent, a matting agent, organic fine particles, and the like can be added to the active energy ray-curable resin composition of the present invention.

  The active energy ray-curable resin composition of the present invention can be used by blending an organic solvent and adjusting the viscosity as necessary. Examples of the organic solvent 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, xylene And the like, glycol ethers such as propylene glycol monomethyl ether, acetates such as methyl acetate, ethyl acetate and butyl acetate, and diacetone alcohol. These organic solvents may be used alone or in combination of two or more.

  When two or more organic solvents are used, a combination of glycol ethers such as propylene glycol monomethyl ether and ketones such as methyl ethyl ketone and alcohols such as methanol, or a combination of ketones such as methyl ethyl ketone and alcohols such as methanol From the viewpoint of the coating film appearance, it is preferable to use two or more alcohols such as methanol in combination.

  The active energy ray-curable resin composition of the present invention can be diluted to 3 to 60% by weight, preferably 5 to 40% by weight, using the organic solvent, and applied to a substrate.

  In producing the active energy ray-curable resin composition of the present invention, the inorganic oxide-acrylic resin composite (α), the photocationic polymerization initiator (β), and optional components, which are essential components, are included. The above (C) component, (F) component, and other compounding components of other additives can be obtained by appropriately mixing them in any order, but in view of preventing aggregation, the photocationic polymerization initiator (β) Is preferably blended last. Further, the mixing method is not particularly limited, and the mixing can be performed by various methods.

"Coating agent"
The active energy ray-curable resin composition of the present invention is effectively used as a curable resin composition for coating film formation, such as a coating agent on various substrates, and is particularly antireflective formed on the display surface. It is preferably used as a film forming material. Among these, the antireflective film composed of a high refractive index layer and a low refractive index layer is useful as a material for forming a low refractive index layer that is the outermost layer. For example, the active energy ray-curable resin composition of the present invention is applied to a substrate (after further drying if a composition diluted with an organic solvent is applied), then the active energy ray Is cured by irradiation.

  As the substrate, a transparent film such as polyester, polyolefin, polyacrylate, polycarbonate, acetylated cellulose, polyether sulfone and the like can be used. Furthermore, you may use what provided the easily bonding layer on the base-material surface, and what surface-treated, such as corona treatment.

  Moreover, when the low refractive index layer formed by hardening the active energy ray-curable resin composition of the present invention is used on the substrate having a high refractive index layer provided thereon as described above. The antireflection effect can be further improved, which is preferable. When used in the above applications, it is more preferable that the high refractive index layer also has scratch resistance. Examples of a method for forming a layer having a high refractive index and scratch resistance (high refractive index layer) on the substrate include titanium oxide, zirconium oxide, zinc oxide, tin oxide, indium tin oxide, and antimony-doped oxide. A base material, which is a transparent film, comprising a resin composition having a high refractive index such as tin and fine particles having an average particle diameter of 1 to 200 nm dispersed in the active energy ray-curable resin composition of the present invention. The method of apply | coating and hardening to the surface is mention | raise | lifted.

  Examples of the method for coating the base material with the coating agent containing the active energy ray-curable resin composition of the present invention include bar coater coating, air knife coating, gravure coating, dip coating, and spin coat coating. A known coating method such as can be used.

  The thickness of the coating film formed by applying the coating agent is such that the film thickness after drying is less than the visible light wavelength, and if possible, the thickness is ¼ of the visible light wavelength. It is preferable to apply, specifically, the thickness is more preferably 100 to 300 nm, particularly preferably 100 to 200 nm. In other words, the coating film thickness is set so that the wavelength indicating the minimum value of the reflectance in the low-refractive index layer to be an antireflection film formed using the coating agent is 400 to 800 nm, more preferably 520 to 650 nm. It is preferable to do.

  As a condition for applying the coating agent, it is preferable to set the humidity to be low because the cationic polymerization by irradiation with active energy rays proceeds smoothly. Specifically, the relative humidity is 40% or less. It is preferable to set to.

  And the said coating agent is apply | coated to a base material, a coating-film layer is formed, an active energy ray is irradiated to this, and a coating-film layer is hardened, and an antireflection film is formed in the base-material surface.

  When the said coating agent contains a solvent, it is preferable to harden | cure by performing active energy ray irradiation after removing a solvent by making it dry. The drying condition is not particularly limited as long as the solvent can be removed in a temperature range that does not damage the substrate, and examples include drying conditions at 60 to 100 ° C. for several minutes.

  Thus, the thickness of the cured layer obtained by curing the coating layer may be less than the visible light wavelength, and if possible, it may be a thickness of 1/4 of the visible light wavelength. Specifically, the thickness is preferably 100 to 300 nm, particularly preferably 100 to 200 nm.

  As the active energy rays, for example, rays such as far ultraviolet rays, ultraviolet rays, near ultraviolet rays, infrared rays, electromagnetic waves such as X rays and γ rays, electron beams, proton rays, neutron rays, etc. can be used. Curing by ultraviolet irradiation is advantageous because of the availability of the irradiation device and the price.

As a method of curing by ultraviolet irradiation, a high pressure mercury lamp emitting ultra-high pressure mercury lamp, ultra high pressure mercury lamp, carbon arc lamp, metal halide lamp, xenon lamp, chemical lamp, electrodeless discharge lamp, LED, etc. There is a method of curing by irradiating with ultraviolet rays. Further, the irradiation amount is appropriately set depending on the irradiation device or the like, but it is sufficient that it can be cured to such an extent that the scratch resistance can be exhibited. In the case of ultraviolet irradiation, usually 100 to 2000 mJ / cm ^2. It is. In addition, after the ultraviolet irradiation, heating can be performed as necessary to complete the curing.

  Specifically, the active energy ray-curable resin composition of the present invention is used as a material for forming an antireflection film (low refractive index layer) formed on a display (transparent resin substrate). Excellent pot life. Furthermore, the antireflection film formed by cationic photopolymerization is formed into a coating film having excellent scratch resistance even when the film thickness is less than 1 μm and is necessary for lowering the refractive index. The active energy ray-curable resin composition of the present invention is useful as various film forming materials such as various protective coating agents including the coating agent that becomes the antireflection film forming material.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated further more concretely, this invention is not limited to a following example, unless the summary is exceeded. In the examples, “parts” and “%” mean weight standards.

[Example 1]
<Preparation of base film>
5.0 parts of urethane (meth) acrylate (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., trade name “UV-7600”), 1-hydroxycyclohexyl phenyl ketone (made by Ciba Japan Co., Ltd., trade name “Irgacure” as photo radical polymerization initiator) 184 ") and 5.0 parts of 1-methoxy-2-propanol as a solvent were prepared, and these were mixed to prepare an active energy ray-curable resin composition for a high refractive index layer. Next, after applying the active energy ray-curable resin composition for a high refractive index layer on the surface of a polyethylene terephthalate (PET) film (manufactured by Toray Industries Inc., Lumirror: film thickness 100 μm) with a # 8 bar coater (film) After drying for 2 minutes at 80 ° C. (thickness: 5.6 μm), the substrate film was produced by irradiating with ultraviolet rays (irradiation amount: 500 mJ / cm ² ) and curing.

<Preparation of acrylic resin (A)>
A 500 mL flask equipped with a stirrer, a reflux condenser, a nitrogen inlet, and a thermometer was purged with nitrogen, and then, the fluorine atom-containing (meth) acrylic acid ester monomer (a1) was added to this flask as 1H, 1H-tri 18 parts of fluoroethyl methacrylate (trade name “M-3F” manufactured by Kyoeisha Chemical Co., Ltd.), 3,4-epoxycyclohexylmethyl methacrylate (Daicel Chemical Industries, Ltd.) as an epoxy group-containing (meth) acrylic acid ester monomer (a2) Product, "Cyclomer M100") 6 parts, hydroxyl group-containing (meth) acrylic acid ester monomer (a3), 2-hydroxyethyl methacrylate 6 parts, chain transfer agent 1.2 parts lauryl mercaptan, solvent 1 -90 parts of methoxy-2-propylacetate is added, and further a polymerization initiator And 2,2'-azo-bis-dimethyl valeronitrile added (Otsuka Chemical Co., Ltd., trade name "ADVN") 0.125 parts, the reaction was started at 65 ° C.. After 3 hours, 0.125 part of the polymerization initiator was added and reacted for another 3 hours, then the temperature was raised to 100 ° C. and kept for 0.5 hours, and then cooled to room temperature (25 ° C.), An acrylic resin (A-1) (solid content 25%; weight average molecular weight 30,000) solution containing a fluorine atom-containing structural moiety and an epoxy group was obtained.

  The weight average molecular weight of the obtained acrylic resin (A-1) was measured according to the method shown below.

<Method for measuring weight average molecular weight>
The weight average molecular weight is based on standard polystyrene molecular weight conversion, and high-performance liquid chromatography (manufactured by Japan Waters, “Waters 2695 (main body)” and “Waters 2414 (detector)”), column: Shodex GPC KF-806L ( Exclusion limit molecular weight: 2 × 10 ⁷ , separation range: 100 to 2 × 10 ⁷ , theoretical plate number: 10,000 plate / piece, filler material: styrene-divinylbenzene copolymer, filler particle size: 10 μm) It was measured by using this series.

Moreover, when the unreacted monomer residual amount in acrylic resin (A-1) was quantified according to the following method, it was 0.5%.
And the weight ratio which a fluorine atom occupies in acrylic resin (A-1) calculated | required from the preparation monomer weight ratio, since the unreacted monomer residual amount was less than 1 weight% of the preparation monomer amount, and 20 weight % Was estimated.
Furthermore, when the ratio which an epoxy group accounts to acrylic resin (A-1) was calculated | required from the preparation monomer weight ratio, it was 974 as an epoxy equivalent.

<Quantification method of remaining amount of unreacted monomer>
The solution of the acrylic resin (A-1) is analyzed by GC / MS, and the mass of the residual monomer in the acrylic resin (A-1) is determined from a calibration curve determined in advance, and the weight is calculated based on the charged monomer mass. As a ratio. The conditions of GC / MS are as follows.
AS part condition: 7683 Series manufactured by Agilent Technologies. Inject amount 1.0μL
GC section condition: 6890N Network GC System manufactured by Agilent Technologies. Column DB-17MS (Crosslinked Methyl Siloxane) 29.3 m (l) × 0.25 mm (id) × 0.25 μm (d), flow rate 1.0 mL / min. Column temperature 40 ° C. × 5 minutes → 220 ° C. × 10 minutes, heating rate 10 ° C./min. Inlet 220 ° C. Carrier gas He. Split ratio 30: 1.
MS part condition: 5973inert MassSelective Detector manufactured by Agilent Technologies. Mass range 10-600. Ion source temperature 230 ° C. Quadrupole temperature 150 ° C. The number of scans is 2.52 / second.

<Preparation of Inorganic Oxide-Acrylic Resin Composite (α) (Production Method [1])>
In a solution of the acrylic resin (A-1), 3-isocyanatopropyltriethoxysilane (E-1) (manufactured by Shin-Etsu Chemical Co., Ltd., trade name “KBE-9007”) 0.23 part [0.92 mmol, acrylic Equivalent to 2 mol% of all hydroxyl groups in the resin (A-1)] is added to 1.5 parts of 1-methoxy-2-propyl acetate, and 0.03 part of dibutyltin dilaurate is added as a catalyst. By reacting at 80 ° C. for 2 hours, a reaction product of the acrylic resin (A-1) and the 3-isocyanatepropyltriethoxysilane (E-1) was obtained. When the liquid at the end of the reaction was titrated with an amine, no isocyanate group was observed.

  Next, the reaction product of the acrylic resin (A-1) and 3-isocyanatopropyltriethoxysilane (E-1) is gradually cooled to room temperature (25 ° C.), and then, as colloidal silica, 1- Colloidal silica (B-1) dispersed in methoxy-2-propyl acetate (manufactured by Nissan Chemical Industries, trade name “PMA-ST”; average particle size 10-15 nm; solid content 30 wt%) 60 parts, water 0 .1 part and 1.5 parts of acetic acid as a catalyst were added and reacted at 75 ° C. for 4 hours to obtain an inorganic oxide-acrylic resin composite (α-1).

<Preparation of active energy ray-curable resin composition>
2.4 parts of the above inorganic oxide-acrylic resin composite (α-1), 0.044 parts of trade name “Adekaoptomer SP-170” manufactured by ADEKA as photocationic polymerization initiator (β-1), An active energy ray-curable resin composition was obtained by mixing 1.0 part of 1-methoxy-2-propyl acetate as a solvent.

The active energy ray-curable resin composition is applied onto the previously prepared base film using a # 2 bar coater, dried at 80 ° C. for 2 minutes, and then irradiated with ultraviolet rays at a dose of 500 mJ / cm ^2. Was applied to cure the coating film to obtain a laminate (an antireflection film which is a cured coating layer formed on the base film). The thickness of the coating film hardening layer which consists of this active energy ray curable resin composition after hardening was 0.5 micrometer.

[Example 2]
<Preparation of hydrolyzate of epoxy group-containing alkoxysilane (C)>
In a 300 mL flask equipped with a stirrer, a cooler, and a thermometer, 48 parts of 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., trade name “KBM-303”), 2-butanone While adding 96 parts, while stirring, 5 parts of a 0.1 wt% aqueous potassium hydroxide solution was added, and a hydrolysis reaction was carried out at 70 ° C. for 4 hours. After cooling to room temperature (25 ° C.), the mixture was neutralized by adding acetic acid, and the hydrolyzate (C-1) of an epoxy group-containing alkoxysilane was obtained by removing the solvent with a rotary evaporator.

<Preparation of active energy ray-curable resin composition>
2.4 parts of inorganic oxide-acrylic resin composite (α-1) prepared in Example 1 above, 0.96 part of hydrolyzate of epoxy group-containing alkoxysilane (C-1), photocationic polymerization initiator By mixing 0.056 part of a trade name “ADEKA OPTMER SP-170” manufactured by ADEKA as (β-1) and 5.4 parts of 1-methoxy-2-propyl acetate as a solvent, the active energy ray curability is mixed. A resin composition was obtained.

The active energy ray-curable resin composition is applied onto the previously prepared base film using a # 2 bar coater, dried at 80 ° C. for 2 minutes, and then irradiated with ultraviolet rays at a dose of 500 mJ / cm ^2. Was applied to cure the coating film to obtain a laminate (an antireflection film which is a cured coating layer formed on the base film). The thickness of the coating film hardening layer which consists of this active energy ray curable resin composition after hardening was 0.50 micrometer.

[Comparative Example 1]
Colloidal silica (manufactured by Nissan Chemical Industries Ltd., trade name “PMA-”) dispersed in 1-methoxy-2-propyl acetate as colloidal silica, 1.5 parts of the acrylic resin (A-1) prepared in Example 1 above. ST ": average particle size 10 to 15 nm, solid content 30% by weight) 0.73 parts, as photocationic polymerization initiator (β-1), manufactured by ADEKA, 0.044 parts of" Adekaoptomer SP-170 ", solvent As a result, 0.8 part of 1-methoxy-2-propyl acetate was mixed to obtain an active energy ray-curable resin composition.

The active energy ray-curable resin composition is applied onto the previously prepared base film using a # 2 bar coater, dried at 80 ° C. for 2 minutes, and then irradiated with ultraviolet rays at a dose of 500 mJ / cm ^2. Was applied to cure the coating film to obtain a laminate (an antireflection film which is a cured coating layer formed on the base film). The thickness of the coating film hardening layer which consists of this active energy ray curable resin composition after hardening was 0.53 micrometer.

[Comparative Example 2]
Colloidal silica (manufactured by Nissan Chemical Industries Ltd., trade name “PMA-”) dispersed in 1-methoxy-2-propyl acetate as colloidal silica, 1.5 parts of the acrylic resin (A-1) prepared in Example 1 above. ST ": average particle size 10 to 15 nm; solid content 30 wt%) 0.73 parts, epoxy group-containing alkoxysilane hydrolyzate (C-1) prepared in Example 2 0.95 parts, photocationic polymerization By mixing 0.041 part of trade name “ADEKA OPTMER SP-170” as an initiator (β-1) and 5.4 parts of 1-methoxy-2-propyl acetate as a solvent, an active energy ray A curable resin composition was obtained.

The active energy ray-curable resin composition is applied onto the previously prepared base film using a # 2 bar coater, dried at 80 ° C. for 2 minutes, and then irradiated with ultraviolet rays at a dose of 500 mJ / cm ^2. Was applied to cure the coating film to obtain a laminate (an antireflection film which is a cured coating layer formed on the base film). The thickness of the coating film cured layer made of the active energy ray-curable resin composition after curing was 0.52 μm.

  The pot life of each active energy ray-curable resin composition thus obtained, and the refractive index and transparency (haze value) of the cured film formed using each active energy ray-curable resin composition. The scratch resistance was measured and evaluated according to the following method. These results are also shown in Table 1 below.

[Pot life]
Each obtained active energy ray-curable resin composition was stored at room temperature (25 ° C.), and the period until gelation was confirmed by visual observation was measured.

[Refractive index]
The active energy ray-curable resin composition was concentrated to about 80% solid content using a rotary evaporator, and then applied onto a polytetrafluoroethylene sheet using an applicator so as to have a film thickness of 200 μm. This was put into a dryer (80 ° C.) to remove the solvent, and then the coating film was cured by irradiating with ² J / cm ² of ultraviolet rays.
Next, the cured film was peeled from the polytetrafluoroethylene sheet. Using this cured film, the refractive index of the cured film was measured using an Abbe refractometer (manufactured by Atago Co., Ltd., NAR-1T) according to JIS K7105.

[Transparency (haze value)]
Above Examples 1-2, using a laminate produced in Comparative Example 1 and 2, in accordance with JIS K7105, the haze was measured values. In addition, the haze meter (Nippon Denshoku Industries make, NDH2000) was used for the measurement.

[Abrasion resistance]
Above Examples 1-2, using a laminate produced in Comparative Example 1 and 2 ASTM D1044 was performed according to (Standard Test Method for Resistance of Transparent Plastics to Surface Abrasion), the difference of Δ haze haze values before and after the test As shown. A smaller value (Δhaze) indicates that the antireflection film, which is a coating film cured layer in the scratch resistance test, is less damaged, and it can be said that the scratch resistance is excellent.

From the above results, the laminates of Examples 1 and 2 formed using the active energy ray-curable resin composition containing the inorganic oxide-acrylic resin composite (α) have a low refractive index. It can be seen that the laminate is excellent in transparency and scratch resistance. Furthermore, it turns out that the active energy ray curable resin composition which is Examples 1-2 is excellent also in pot life.

  On the other hand, the cured film of Comparative Example 1 formed using the active energy ray-curable resin composition produced by simply mixing silica has a high haze value and is inferior in transparency. The refractive index was not measurable because it was cloudy. Moreover, it can be seen that the Δ haze value is extremely high and the scratch resistance is poor. Furthermore, the pot life of the active energy ray-curable resin composition of Comparative Example 1 was 8 days, which was an extremely short result compared to the Examples.

  The cured film of Comparative Example 2 formed using the active energy ray-curable resin composition prepared by simply mixing silica with the hydrolyzate of epoxy group-containing alkoxysilane (C) The value of Δhaze is substantially the same as that of the example, and it is understood that the scratch resistance is about the same as that of the example. However, it can be seen that the haze value is high and the transparency is inferior, the refractive index is higher than that of the cured film of the example, and a sufficiently low refractive index is not obtained. Furthermore, the pot life of the active energy ray-curable resin composition of Comparative Example 2 was 31 days, which was shorter than that of Example.

  The active energy ray-curable resin composition of the present invention is excellent in pot life, and further has a film having an effect of excellent scratch resistance even with a thickness required for a low refractive index of less than 1 μm by photocationic polymerization. Can be formed. Therefore, the active energy ray-curable resin composition of the present invention is useful as various coating agents such as a coating agent that forms an antireflection film that is a low refractive index layer formed on the surface of a transparent resin substrate such as a display. It is.

Claims (10)

An acrylic resin (A) containing a hydroxyl group and containing a fluorine atom-containing structural moiety and an epoxy group, and inorganic oxide fine particles (B) containing colloidal silica as a main component include an alkoxy group in one molecule. And an inorganic oxide-acrylic resin composite (α) formed through a bonding site represented by the following general formula (1 ) derived from a silicon compound (E) having both an isocyanate group and a photocationic polymerization An active energy ray-curable resin composition comprising an initiator (β).
[Chemical 1]
—O—Si—R ¹ —NHCOO— (1)
In [the formula (1), R ¹ is a linear or branched alkylene group having 1 to 10 carbon atoms. ]   The acrylic resin (A) is a fluorine atom-containing (meth) acrylic acid ester monomer (a1), an epoxy group-containing (meth) acrylic acid ester monomer (a2), and a hydroxyl group-containing (meth) acrylic acid ester monomer (a3). The active energy ray-curable resin composition according to claim 1, which is an acrylic resin obtained by copolymerizing a copolymerization component [I] containing   The active energy ray-curable resin composition according to claim 1 or 2, wherein the acrylic resin (A) has a weight average molecular weight of 10,000 to 100,000.   The average particle diameter of inorganic oxide microparticles | fine-particles (B) is 10-100 nm, The active energy ray-curable resin composition as described in any one of Claims 1-3 characterized by the above-mentioned.   The active energy ray-curable resin composition according to any one of claims 1 to 4, wherein the inorganic oxide fine particles (B) are silica having a hollow structure.   6. The active energy ray-curable resin composition according to any one of claims 1 to 5, wherein the inorganic oxide fine particles (B) are modified with a silane coupling agent.   The activity according to any one of claims 1 to 6, wherein the compounding amount of the inorganic oxide fine particles (B) is 25 to 100 parts by weight with respect to 100 parts by weight of the acrylic resin (A). Energy ray curable resin composition. A method according to claim 1-7 actinic radiation-curable resin composition according,
[I] A co-polymer containing a fluorine atom-containing (meth) acrylic acid ester monomer (a1), an epoxy group-containing (meth) acrylic acid ester monomer (a2) and a hydroxyl group-containing (meth) acrylic acid ester monomer (a3). A step of producing an acrylic resin (A) containing a fluorine atom-containing structural site and an epoxy group by copolymerizing the polymerization component [I];
[Ii] After reacting the hydroxyl group in the acrylic resin (A) with the isocyanate group of the silicon compound (E) having both an alkoxy group and an isocyanate group in one molecule, the alkoxy group in the reaction product By reacting with the hydroxyl group in the inorganic oxide fine particles (B) containing colloidal silica as a main component, the acrylic resin (A) and the inorganic oxide fine particles (B) containing colloidal silica as a main component are: A step of producing an inorganic oxide-acrylic resin composite (α) formed by binding via a binding site represented by the general formula (1);
[Chemical formula 2]
—O—Si—R ¹ —NHCOO— (1)
In [the formula (1), R ¹ is a linear or branched alkylene group having 1 to 10 carbon atoms. ]
[Iii] A method for producing an active energy ray-curable resin composition comprising a step of mixing a photocationic polymerization initiator (β) together with the inorganic oxide-acrylic resin composite (α). . A coating agent comprising the active energy ray-curable resin composition according to any one of claims 1 to 7 . A laminate comprising an antireflection film formed on the transparent substrate surface using the coating agent according to claim 9 .