WO2017195752A1 - Photocurable resin composition, photocurable coating, and cured product - Google Patents

Abstract

An embodiment of the present invention relates to a photocurable resin composition that is used to protect at least a portion of an end of a glass substrate and has a viscosity of 0.4 to 20 Pa∙s.

Description

Photocurable resin composition, photocurable paint, and cured product

The present disclosure relates to a photocurable resin composition, a photocurable paint, a cured product, a glass substrate, a display device, a portable terminal, a method for producing a cured product, and a method for producing a protected glass substrate.

In mobile terminals such as smartphones and tablets, screens are becoming larger and thinner for lightening. Accordingly, the cover glass used is also becoming thinner. Therefore, high-strength chemically strengthened glass is widely used for the cover glass. The cover glass may crack at the end due to contact or impact during the manufacturing process. In chemically strengthened glass, the strength tends to decrease significantly due to cracks.

Also, recently, a design with a cover glass raised against the case of mobile terminals has become popular. When the cover glass is raised, the end portion is exposed to direct contact with the outside or an impact from the outside, and cracks are easily generated. Therefore, a protective film that protects the cover glass from contact or impact by being provided at the end and prevents the occurrence of cracks is required (see, for example, Patent Documents 1 and 2). The protective film is formed, for example, by applying a liquid photocurable coating to the end of the cover glass.

JP 2012-111688 A Special table 2012-527399 gazette

However, in recent years, even in the case of a cover glass provided with a protective film, there has been a case where cracks are generated. Therefore, the present disclosure provides a photocurable resin composition, a photocurable paint, and a cured product having an excellent protective effect. In addition, the present disclosure provides a glass substrate having excellent durability, a display element including the glass substrate, and a portable terminal. Furthermore, this indication provides the manufacturing method for manufacturing the said hardened | cured material and the said glass base material efficiently.

The present invention includes various embodiments. Examples of embodiments are listed below. The present invention is not limited to the following embodiments.

One embodiment relates to a photocurable resin composition that is used to protect at least a part of an edge of a glass substrate and has a viscosity of 0.4 to 20 Pa · s.

The photocurable resin composition may contain a colorant.

Moreover, other embodiment is related with the photocurable coating material using the said photocurable resin composition.

Another embodiment relates to a cured product obtained by curing the photocurable resin composition or the photocurable paint.

Another embodiment relates to a glass substrate in which at least a part of the end is protected by the cured product.

Other embodiments relate to a display device or a portable terminal provided with the glass substrate.

Furthermore, other embodiment is related with the manufacturing method of hardened | cured material including the process of hardening the said photocurable resin composition or the said photocurable coating material by light irradiation.

In another embodiment, the photocurable resin composition or the photocurable paint is applied to at least a part of an end portion of a glass substrate to form a coating film, and The present invention relates to a method for producing a protected glass substrate, which includes a step of curing by irradiation to form a protective film.

The disclosure of the present application is related to the subject matter described in Japanese Patent Application No. 2016-093775 filed on May 9, 2016, the entire disclosure of which is incorporated herein by reference.

According to the present disclosure, a photocurable resin composition, a photocurable paint, and a cured product having an excellent protective effect are provided. Moreover, according to this indication, the glass substrate excellent in durability, a display element provided with this, and a portable terminal are provided. Furthermore, according to this indication, the manufacturing method for manufacturing the said hardened | cured material and the said glass base material efficiently is provided.

FIG. 1A is a schematic plan view illustrating an example of a glass substrate according to an embodiment, and FIG. 1B is a schematic cross-sectional view illustrating an example of a glass substrate according to an embodiment. FIG. 2A is a schematic plan view illustrating an example of a glass substrate according to an embodiment in which a cured product is provided on a side surface, and FIGS. 2B and 2C are diagrams in which the cured product is provided on a side surface. It is a cross-sectional schematic diagram which shows an example of the glass base material of one embodiment.

An embodiment of the present invention will be described. The present invention is not limited to the following embodiments.
The inventor has found that with the reduction in thickness of the glass substrate, the portion where the protective film is provided has become narrower, making it difficult to form a protective film capable of exhibiting a sufficient protective effect, and specific photocuring properties. It has been found that by using the resin composition, a protective film having an excellent protective effect can be formed even in a narrow portion, and the present invention has been completed.

<Photocurable resin composition>
According to one embodiment, the photocurable resin composition is a composition that is used to protect at least a part of the edge of the glass substrate and has a viscosity of 0.4 to 20 Pa · s. This photocurable resin composition can be preferably used as a material for protecting the glass substrate because it can be easily applied to the end of the glass substrate.

The inventor has considered that one of the causes that a sufficient protective effect cannot be obtained by the conventional photocurable resin composition is a defective formation of the protective film. Usually, a protective film is formed by apply | coating a liquid photocurable resin composition to the edge part of a glass base material, and making it harden | cure. Although the degree varies depending on the coating method and / or the curing method, in general, in any method, there is a time difference between the end point of the coating step and the start point of the curing step. That is, time elapses from the end of the coating process to the start of the curing process. Therefore, the shape of the applied liquid photo-curable resin composition cannot be maintained until it is cured, and the protective film may not be formed into a shape that exhibits a sufficient protective effect. Thought that would occur. Therefore, according to one embodiment, the photocurable resin composition is provided as a composition that can be formed in a favorable shape even in a narrow portion such as an end portion of a thinned glass substrate. Is.

That is, if the photocurable resin composition has a low viscosity, the photocurable resin composition will flow out between the coating process and the curing process, and the cured product (protective film) cannot be formed in a good shape. , Protection performance will be inferior. On the other hand, in the coating process, if the photocurable resin composition has a high viscosity, coating becomes difficult, and the protective film cannot be obtained in a good shape. According to one embodiment, in the photocurable resin composition, it is possible to form a protective film having an excellent protective effect by setting the liquid viscosity to a specific range. Moreover, workability | operativity improves by making liquid viscosity into a specific range, and it leads to the productivity improvement of a glass base material.

Examples of the method for applying the photocurable resin composition include a potting method, a dipping method, a spray method, and a roll coating method. You may use dispensers, such as a syringe-type dispenser and a jet-type dispenser, for application | coating. It is preferable that the coating method of a photocurable resin composition is a method of apply | coating a liquid photocurable resin composition directly to a glass base material. The method using a dispenser is a preferred method that can efficiently protect the glass substrate.

For curing the photocurable resin composition, ultraviolet rays are preferably used. The light source used is not particularly limited, and examples thereof include LED lamps, mercury lamps (low pressure, high pressure, ultrahigh pressure, etc.), metal halide lamps, excimer lamps, xenon lamps, etc., preferably LED lamps, mercury lamps, Metal halide lamps and the like.

Usually, it takes time to put the applied photocurable resin composition into the curing step, regardless of which application method and / or curing method is used. This photocurable resin composition has an excellent protective effect in various coating methods and curing methods.

The viscosity of the photocurable resin composition is 0.4 to 20 Pa · s. If it is less than 0.4 Pa, the photocurable resin composition flows out after coating, and the photocurable resin composition cannot maintain a good shape. Moreover, the film thickness of a protective film becomes inadequate. If it exceeds 20 Pa · s, coating becomes difficult. In addition, pulling, clogging, and the like occur, and workability decreases. From the viewpoint of obtaining a good protective effect, the viscosity of the photocurable resin composition is preferably 0.7 Pa · s or more, more preferably 1.0 Pa · s or more, and further preferably 1.3 Pa · s. Above, especially preferably 1.5 Pa · s or more. The viscosity of the photocurable resin composition is preferably 10 Pa · s or less, more preferably 5 Pa · s or less, and further preferably 3 Pa · s or less, from the viewpoint of obtaining a good protective effect. Particularly preferably, it is 2.5 Pa · s or less.

The viscosity of the photocurable resin composition can be measured using a single cylindrical rotational viscometer (B-type viscometer). An example of a single cylindrical rotational viscometer is “TVB-10 type viscometer” manufactured by Toki Sangyo Co., Ltd.

In one embodiment, the photocurable resin composition preferably contains (A) a monomer having a polymerizable unsaturated group and (B) an acrylic compound. The photocurable resin composition may contain optional components such as (C) a phosphoric acid compound, (D) a photopolymerization initiator, and / or (E) a colorant. The photocurable resin composition may contain only one kind of each of these components, or two or more kinds thereof. Although a photocurable resin composition may contain a solvent, it does not need to contain a solvent from a viewpoint of obtaining a favorable protective effect.

The viscosity of the photocurable resin composition can be adjusted, for example, by changing the content of each component. When it is desired to increase the viscosity, the content of the monomer (A) should be reduced and the content of the acrylic compound (B) should be increased. On the other hand, when it is desired to reduce the viscosity, the content of the (B) acrylic compound may be reduced and the content of the (A) monomer may be increased.

Hereinafter, each component will be described.
((A) Monomer having polymerizable unsaturated group)
(A) As the polymerizable unsaturated group possessed by the monomer, for example, vinyl group (ethenyl group), ethynyl group, allyl group, (meth) acryloyl group, (meth) acryloyloxy group, (meth) acryloylamino group And groups having a carbon-carbon double bond such as The monomer (A) preferably has a (meth) acryloyloxy group or a (meth) acryloylamino group. (A) The monomer has at least one polymerizable unsaturated group in the molecule.

Examples of the (A) monomer include a compound having a (meth) acryloyl group, a compound having a (meth) acryloyloxy group, a compound having a (meth) acryloylamino group, and the like. These compounds are preferably used from the viewpoint of enhancing the protective effect. (A) When the monomer includes “a compound having a (meth) acryloyl group”, it means that the monomer includes at least one of a compound having an acryloyl group and a compound having a methacryloyl group. Regarding the term “(meth)”, it means that a compound having a (meth) acryloyloxy group and a compound having a (meth) acryloylamino group also include at least one of them.

Examples of (A) monomers include (A-1) (meth) acrylic acid ester monomers, (A-2) (meth) acrylamide monomers, and the like. (A) When a monomer says "it contains (meth) acrylic acid ester", it means containing at least any one of acrylic acid ester and methacrylic acid ester. The same applies to “(meth) acrylamide”. As (A) monomer, a compound different from (B) acrylic compound and (C) phosphoric acid compound described later is used. Regarding the term “(meth)”, it is meant that (B) the acrylic compound and (C) the phosphoric acid compound also contain at least one.

Examples of the monofunctional (meth) acrylic acid ester monomer include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, tert-butyl (meth) acrylate, Butoxyethyl (meth) acrylate, isoamyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate , Undecyl (meth) acrylate, lauryl (meth) acrylate, tridecyl (meth) acrylate, tetradecyl (meth) acrylate, pentadecyl (meth) acrylate, hexadecyl (meth) acrylate, Thearyl (meth) acrylate, behenyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-chloro-2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) Acrylate, methoxypolyethylene glycol (meth) acrylate, ethoxypolyethylene glycol (meth) acrylate, methoxypolypropylene glycol (meth) acrylate, ethoxypolypropylene glycol (meth) acrylate, mono (2- (meth) acryloyloxyethyl) succinate, (meth) Aliphatic (meth) such as a reaction product of acrylic acid and glycidyl ester (for example, “Cardura E-10” manufactured by Momentive Performance Materials) Chryrate; cyclopentyl (meth) acrylate, cyclohexyl (meth) acrylate, cyclopentyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, isobornyl (meth) acrylate, mono (2- (meth) And alicyclic (meth) acrylates such as acryloyloxyethyl) tetrahydrophthalate and mono (2- (meth) acryloyloxyethyl) hexahydrophthalate.

Examples of the bifunctional (meth) acrylic acid ester monomer include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, and tetraethylene glycol di (meth) acrylate. , Polyethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, tetrapropylene glycol di (meth) acrylate, polypropylene glycol di (meth) Acrylate, ethoxylated polypropylene glycol di (meth) acrylate, 1,3-butanediol di (meth) acrylate, 1,4-butanediol di (meth) acrylate , Neopentyl glycol di (meth) acrylate, 3-methyl-1,5-pentanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 2-butyl-2-ethyl-1, 3-propanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, 1,10-decanediol di (meth) acrylate, glycerin di (meth) acrylate, tricyclodecane dimethanol (meth) acrylate , Aliphatic (meth) acrylates such as ethoxylated 2-methyl-1,3-propanediol di (meth) acrylate; cyclohexanedimethanol (meth) acrylate, ethoxylated cyclohexanedimethanol (meth) acrylate, propoxylated cyclohexanedimethanol (Meta) a Relate, ethoxylated propoxylated cyclohexanedimethanol (meth) acrylate, tricyclodecane dimethanol (meth) acrylate, ethoxylated tricyclodecane dimethanol (meth) acrylate, propoxylated tricyclodecane dimethanol (meth) acrylate, ethoxylated Propoxylated tricyclodecane dimethanol (meth) acrylate, ethoxylated hydrogenated bisphenol A di (meth) acrylate, propoxylated hydrogenated bisphenol A di (meth) acrylate, ethoxylated propoxylated hydrogenated bisphenol A di (meth) acrylate, Ethoxylated hydrogenated bisphenol F di (meth) acrylate, propoxylated hydrogenated bisphenol F di (meth) acrylate, ethoxylated propoxylated hydrogenated bisphenol F di (meth) acrylate And alicyclic (meth) acrylates such as relate.

Examples of the trifunctional or higher functional (meth) acrylic acid ester monomers include trimethylolpropane tri (meth) acrylate, ethoxylated trimethylolpropane tri (meth) acrylate, propoxylated trimethylolpropane tri (meth) acrylate, Ethoxylated propoxylated trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, ethoxylated pentaerythritol tri (meth) acrylate, propoxylated pentaerythritol tri (meth) acrylate, ethoxylated propoxylated pentaerythritol tri (meth) ) Acrylate, pentaerythritol tetra (meth) acrylate, ethoxylated pentaerythritol tetra (meth) acrylate, propoxylated pentaerythritol Tetra (meth) acrylate, ethoxylated propoxylated pentaerythritol tetra (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, dipentaerythritol hexa (meth) aliphatic acrylates such as (meth) acrylate.

(A-1) Monofunctional (meth) acrylic acid ester-based monomer from the viewpoints of compatibility with other components such as acrylic compounds and colorants, and hardness characteristics during curing Monomers, more preferably monofunctional alicyclic (meth) acrylates, and even more preferably isobornyl (meth) acrylate are used.

(Meth) acrylamide monomers include (meth) acrylamide, methyl (meth) acrylamide, dimethyl (meth) acrylamide, ethyl (meth) acrylamide, diethyl (meth) acrylamide, n-propyl (meth) acrylamide, di- n-propyl (meth) acrylamide, isopropyl (meth) acrylamide, diisopropyl (meth) acrylamide, n-butyl (meth) acrylamide, di-n-butyl (meth) acrylamide, isobutyl (meth) acrylamide, diisobutyl (meth) acrylamide, tert-butyl (meth) acrylamide, di-tert-butyl (meth) acrylamide, n-pentyl (meth) acrylamide, di-n-pentyl (meth) acrylamide, n-hexyl (meth) actyl Ruamido, di -n- hexyl (meth) acrylamide, cyclohexyl (meth) acrylamide, dicyclohexyl (meth) acrylamide, (meth) acryloyl morpholine.

(A-2) As a monomer, (meth) acryloylmorpholine is preferably used from the viewpoints of compatibility with other components such as an acrylic compound and a colorant, and hardness characteristics upon curing.

(A) Monomers can be used singly or in combination of two or more. From the viewpoints of compatibility with other components such as an acrylic compound and a colorant, and hardness characteristics during curing, the monomer (A) is preferably used in combination of two or more types (A-1 ) Monomer and (A-2) monomer are more preferably used in combination. (A-1) Monofunctional (meth) acrylic acid ester monomer and (A-2) It is more preferable to use in combination with a monomer.

(A) The content of the monomer is a photocurable resin from the viewpoints of viscosity characteristics, compatibility with other components such as acrylic compounds and colorants, handling properties, productivity, and hardness characteristics during curing. 20 mass% or more is preferable on the basis of the total mass of the composition, 25 mass% or more is more preferable, and 30 mass% or more is still more preferable. Further, from the same viewpoint, the content of the monomer (A) is preferably 50% by mass or less, more preferably 45% by mass or less, and more preferably 40% by mass or less, based on the total mass of the photocurable resin composition. Is more preferable.

When (A-1) monomer and (A-2) monomer are used in combination, the ratio (mass ratio) of (A-2) monomer to (A-1) monomer is preferably It is 0.02 or more, more preferably 0.05 or more, still more preferably 0.08 or more. The ratio (mass ratio) of the monomer (A-2) to the monomer (A-1) is preferably 0.3 or less, more preferably 0.2 or less, and still more preferably 0.15 or less. is there.

((B) Acrylic compound)
(B) The acrylic compound is a compound having at least one (meth) acryloyl group or (meth) acryloyloxy group. For example, (meth) acrylate compounds having a urethane bond can be exemplified. (B) As the acrylic compound, a compound different from the phosphoric acid compound (C) described later is used. A (meth) acrylate compound having a urethane bond is preferably used from the viewpoint of enhancing the protective effect.

Examples of (meth) acrylate compounds having a urethane bond include (meth) acrylic acid monomers having an OH group at the β-position, isophorone diisocyanate, 2,6-toluene diisocyanate, 2,4-toluene diisocyanate, and 1,6-hexa. Reaction products with diisocyanate compounds such as methylene diisocyanate, tris ((meth) acryloxytetraethylene glycol isocyanate) hexamethylene isocyanurate, EO-modified urethane di (meth) acrylate, PO-modified urethane di (meth) acrylate, EO and PO-modified urethane di ( Examples include meth) acrylate and carboxyl group-containing urethane (meth) acrylate. A urethane oligomer is also preferably used as the (meth) acrylate compound having a urethane bond.

(B) The weight average molecular weight of the acrylic compound is preferably 800 from the viewpoints of viscosity characteristics, compatibility with other components such as monomers and colorants, handling properties, productivity, and hardness characteristics upon curing. Above, more preferably 2,000 or more, still more preferably 4,000 or more. The weight average molecular weight of the (B) acrylic compound is preferably 10,000 or less, more preferably 9,000 or less, and still more preferably 7,000 or less, from the same viewpoint. The weight average molecular weight is measured by gel permeation chromatography (GPC), and a value converted to standard polystyrene is used.

Examples of commercially available products include “UA-306H”, “UA-306T”, “UA-306I” manufactured by Kyoeisha Chemical Co., Ltd .; “Art Resin UN-904”, “Art Resin UN-6060S” manufactured by Negami Kogyo Co., Ltd. "Viscoat # 700HV" manufactured by Osaka Organic Chemical Industry Co., Ltd .; "KAYARAD DPHA-40H", "KAYARAD UX-5000" manufactured by Nippon Kayaku Co., Ltd., and the like.

(B) One type of acrylic compound can be used alone, or two or more types can be used in combination.

(B) The content of the acrylic compound is a photocurable resin from the viewpoints of viscosity characteristics, compatibility with other components such as monomers and colorants, handling properties, productivity, and hardness characteristics during curing. 35 mass% or more is preferable on the basis of the total mass of a composition, 40 mass% or more is more preferable, and 45 mass% or more is still more preferable. Further, from the same viewpoint, the content of the (B) acrylic compound is preferably 70% by mass or less, more preferably 65% by mass or less, and more preferably 60% by mass or less, based on the total mass of the photocurable resin composition. Is more preferable.

((C) Phosphate compound)
(C) The phosphoric acid compound is a compound having at least one selected from a phosphoric acid group and a phosphoric ester group and at least one polymerizable unsaturated group. (C) As the polymerizable unsaturated group possessed by the phosphoric acid compound, for example, vinyl group (ethenyl group), ethynyl group, allyl group, (meth) acryloyl group, (meth) acryloyloxy group, (meth) acryloylamino group And groups having a carbon-carbon double bond such as (C) The phosphoric acid compound preferably has a (meth) acryloyloxy group.
(C) The phosphoric acid compound is preferably ethylene oxide-modified phosphoric acid di (meth) acrylate and / or propylene oxide-modified phosphoric acid di (meth) acrylate, and is preferably ethylene oxide-modified phosphoric acid di (meth) acrylate. Is more preferable.

(C) Examples of phosphoric acid compounds include acid phosphooxyethyl (meth) acrylate, acid phosphooxypropyl (meth) acrylate, acid phosphooxybutyl (meth) acrylate, acid phosphooxypentyl (meth) acrylate, and acid phosphooxypoly Examples include compounds represented by the following formula (1) such as oxyethylene glycol monomethacrylate and acid phosphooxypolyoxypropylene glycol monomethacrylate.

In the formula, R ¹ represents hydrogen or a methyl group, R ² represents a linear, branched or cyclic alkyl group, n represents a number of 1 or more, and m represents a number of 1 to 3. The number of carbon atoms of the alkyl group is preferably 1 to 12, more preferably 1 to 9, and still more preferably 1 to 6. n is preferably 1 to 12, more preferably 1 to 6, and still more preferably 1 to 3. m is preferably 1 to 2.

Examples of (C) phosphoric acid compounds include 3-chloro-2-acid phosphooxypropyl (meth) acrylate, phenyl (2- (meth) acryloyloxyethyl) phosphate, diphenyl (2- (meth) acryloyloxyethyl). ) Phosphate, (meth) acryloyloxy-2-hydroxypropyl acid phosphate, (meth) acryloyloxy-3-hydroxypropyl acid phosphate, (meth) acryloyloxy-3-chloro-2-hydroxypropyl acid phosphate, allyl alcohol acid phosphate Etc.

Furthermore, (C) the phosphoric acid compound may be a salt such as a monomethanolamine salt or a monoethanolamine salt.

(C) The phosphoric acid compound is preferably a compound represented by formula (1), more preferably, in formula (1), R ¹ is a methyl group, R ² is a dimethylene group or a pentamethylene group, and n Is a compound in which m is 1-2, and more preferably, in formula (1), R ¹ is a methyl group, R ² is a dimethylene group, n is 1-2, Is a compound in which is 1-2.

(C) Phosphoric acid compounds can be used singly or in combination of two or more.

The content of (C) phosphoric acid compound is 0.01 with respect to a total of 100 parts by mass of (A) monomer and (B) acrylic compound from the viewpoint of obtaining good adhesion to the glass substrate. More than mass part is preferable, 0.1 mass part or more is more preferable, and 0.3 mass part or more is still more preferable. Moreover, content of (C) phosphoric acid compound is 10 with respect to a total of 100 mass parts of (A) monomer and (B) acrylic compound from a viewpoint of maintaining stability of a photocurable resin composition. It is preferably no greater than 5 parts by mass, more preferably no greater than 5 parts by mass, and even more preferably no greater than 3 parts by mass.

((D) Photopolymerization initiator)
(D) What is called a sensitizer is also contained in a photoinitiator. (D) Specific examples of the photopolymerization initiator include acridine; an acridine compound having at least one acridinyl group in the molecule; benzophenone; N, N′-tetramethyl-4,4′-diaminobenzophenone (Michler's ketone), etc. N, N-tetraalkyl-4,4′-diaminobenzophenone; 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1,2-methyl-1- (4-methylthiophenyl) ) -2-morpholinopropanone-1, aromatic ketones such as (1-hydroxycyclohexyl) phenylmethanone; quinones such as alkyl anthraquinones; benzoin ether compounds such as benzoyl alkyl ether; benzoin; benzoin compounds such as alkyl benzoin; Benzyl such as benzyl dimethyl ketal Conductor; 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer, 2- (o-chlorophenyl) -4,5-di (methoxyphenyl) imidazole dimer, 2- (o-fluorophenyl) -4,5-diphenylimidazole dimer, 2- (o-methoxyphenyl) -4,5-diphenylimidazole dimer, 2- (p-methoxyphenyl) -4,5-diphenylimidazole dimer, etc. 2,4,5-triarylimidazole dimer; N-phenylglycine; N-phenylglycine derivative, coumarin compound; onium salt and the like. An aromatic ketone is preferably used from the viewpoint of the balance between the deep curability and the surface curability of the resin composition.

(D) One type of photopolymerization initiator can be used alone, or two or more types can be used in combination.

(D) The content of the photopolymerization initiator is a total of (A) monomer and (B) acrylic compound from the viewpoint of sufficiently curing the surface of the photocurable resin composition and suppressing tackiness of the cured product. 0.1 mass part or more is preferable with respect to 100 mass parts, 1 mass part or more is more preferable, and 5 mass parts or more is still more preferable. In addition, the content of the (D) photopolymerization initiator is based on a total of 100 parts by mass of the (A) monomer and the (B) acrylic compound from the viewpoint of obtaining sufficient curability and adhesion to the deep part. 20 parts by mass or less is preferable, 15 parts by mass or less is more preferable, and 12 parts by mass or less is still more preferable.

((E) Colorant)
(E) As a coloring agent, a coloring agent with small absorption with respect to the light used for hardening is used. (E) Although a dye and a pigment are mentioned as a coloring agent, From a viewpoint of obtaining a uniform photocurable resin composition, Preferably a dye is used, More preferably, (A) Dye which melt | dissolves in a monomer Is used.

It can be confirmed by the following method that the dye is dissolved in the monomer (A).
To a 50 mL beaker, 10 mL of monomer (A) (temperature: 25 ° C.) is added, 10 mg of dye (solid mass) is added, and the mixture is stirred for 1 minute using a glass rod. When the solid matter of the dye cannot be visually confirmed after stirring, it is determined that the dye is dissolved in the monomer (A).

In one embodiment, as the colorant (E), the transmittance of the peak wavelength of light irradiated for curing (hereinafter also referred to as “irradiation light transmittance”) is the average transmittance of visible light (hereinafter referred to as “lighting transmittance”). (Also referred to as “visible light transmittance”). More preferably, it is 20% or more, still more preferably 30% or more, and particularly preferably 40% or more. An upper limit is not specifically limited, The one where the difference of both is large is preferable. When it is 10% or more, both the protection of the end portion and the light shielding property can be achieved in a good state.

In one embodiment, (E) a colorant having an irradiation light transmittance of 60% or more and a visible light transmittance of 50% or less is used as the colorant. The irradiation light transmittance is more preferably 65% or more, and further preferably 70% or more. The visible light transmittance is more preferably 45% or less, still more preferably 40% or less. When the irradiation light transmittance is 60% or more and the visible light transmittance is 50% or less, it is possible to achieve both the protection of the end portion and the light shielding property in a good state.

The peak wavelength of light irradiated for curing refers to the wavelength at which the intensity is maximum for the light irradiated to the photocurable resin composition during curing. When an LED lamp is used as the light source, the peak wavelength is, for example, 365 nm, 385 nm, or the like.

In one embodiment, (E) as a colorant, a colorant having a light transmittance of 365 nm higher than that of visible light by 10% or more is used. More preferably, it is 20% or more, still more preferably 30% or more, and particularly preferably 40% or more. An upper limit is not specifically limited, The one where the difference of both is large is preferable. When it is 10% or more, both the protection of the end portion and the light shielding property can be achieved in a good state.

In one embodiment, (E) a colorant having a light transmittance of 60% or more and a visible light transmittance of 50% or less is used as the colorant. The transmittance of light having a wavelength of 365 nm is more preferably 65% or more, and still more preferably 70% or more. The visible light transmittance is more preferably 45% or less, still more preferably 40% or less. When the transmittance of light with a wavelength of 365 nm is 60% or more and the visible light transmittance is 50% or less, both end protection and light-shielding properties can be achieved in a good state.

(E) The irradiation light transmittance of the colorant can be measured by the following method.
(E) 0.1 part by mass of the colorant (E) is added to 100 parts by mass of the solvent in which the colorant is confirmed to be dissolved to obtain a colorant solution. Using the obtained colorant solution, the transmittance at the peak wavelength of light irradiated for curing is measured with a visible ultraviolet spectrophotometer (for example, “UV-2400PC” manufactured by Shimadzu Corporation). The resolution wavelength is 1 nm and the measurement is performed in the range of 300 to 780 nm.
(E) It can confirm that a coloring agent melt | dissolves in a solvent by the same method as said "the dye dissolves in (A) monomer".
(E) The transmittance of the colorant having a wavelength of 365 nm can also be measured by the same method as the irradiation light transmittance.

The average visible light transmittance refers to the average transmittance of light having a wavelength of 400 to 700 nm. The average visible light transmittance can be measured by the following method.
Using the colorant solution prepared in the same manner as described above, the transmittance is measured every 1 nm in the wavelength range of 400 to 700 nm with a spectrocolorimeter (for example, “CM-3700A” manufactured by Konica Minolta, Inc.). The average value of the obtained values is obtained and used as the average transmittance.

(E) There is no particular limitation on the hue of the colorant. By using colorants having various hues, it is possible to prepare a photocurable resin composition that matches the hue of the bezel. (E) With the photocurable resin composition containing a colorant, a display device and a portable terminal excellent in design can be produced. For example, a black colorant such as a black dye is used.

(E) Examples of the colorant include phthalocyanine blue, phthalocyanine green, iodin green, diazo yellow, aniline black, and perylene black.

Examples of commercially available products include “elixa Black850” manufactured by Orient Chemical Industries, Ltd. “Elexa Black850” has a transmittance of light of wavelength 365 nm higher than the average transmittance of visible light by 10% or more, a transmittance of light of wavelength 365 nm of 60% or more, and a visible light transmittance of The colorant is 50% or less.

(E) The colorant can be used singly or in combination of two or more.

(E) From the viewpoint of obtaining the effect of shielding visible light, the content of the colorant is 0.1 parts by mass or more with respect to 100 parts by mass in total of the (A) monomer and the (B) acrylic compound. Preferably, 0.3 mass part or more is more preferable, and 0.5 mass part or more is still more preferable. In addition, the content of (E) the colorant is the sum of (A) the monomer and (B) the acrylic compound from the viewpoint of curability of the photocurable resin composition, particularly from the viewpoint of sufficiently curing the deep part. 10 mass parts or less are preferable with respect to 100 mass parts, 5 mass parts or less are more preferable, and 3 mass parts or less are still more preferable.

(Additive)
The photocurable resin composition may contain various additives as necessary. Examples of additives include adhesion improvers such as coupling agents, polymerization inhibitors, light stabilizers, antifoaming agents, fillers, antioxidants, chain transfer agents, thixotropy imparting agents, plasticizers, flame retardants, and mold release agents. Agents, surfactants, lubricants, antistatic agents and the like. Known additives can be used as these additives. An additive can be used individually by 1 type or in combination of 2 or more types.

As the coupling agent, for example, titanate coupling agents, silane coupling agents and the like can be used. As a titanate coupling agent, a titanate coupling agent having an alkylate group having at least 1 to 60 carbon atoms, a titanate coupling agent having an alkyl phosphite group, a titanate coupling agent having an alkyl phosphate group, an alkyl pyrone Examples thereof include a titanate coupling agent having a phosphate group.

Silane coupling agents include amino silane coupling agents, ureido silane coupling agents, vinyl silane coupling agents, methacrylic silane coupling agents, epoxy silane coupling agents, mercapto silane coupling agents, and isocyanates. And silane coupling agents.

Examples of the polymerization inhibitor include quinones such as hydroquinone, hydroquinone monomethyl ether, benzoquinone, p-tert-butylcatechol, 2,6-di-tert-butyl-4-methylphenol, and pyrogallol.
Examples of the antifoaming agent include silicone oil, fluorine oil, and polycarboxylic acid polymer.

(Production method)
According to one embodiment, the photocurable resin composition comprises (A) a monomer and (B) an acrylic compound, and optionally (C) a phosphoric acid compound, (D) a photopolymerization initiator, (E) It can manufacture by mixing a coloring agent and / or an additive by stirring. Stirring may be performed by a known method using a stirring bar, a stirring blade, or the like. The temperature at the time of stirring is preferably a temperature at which (E) the colorant can be sufficiently dissolved, and can be, for example, 60 to 90 ° C.

<Photocurable paint>
One embodiment relates to a photocurable coating material using the photocurable resin composition. The photocurable coating contains at least (A) a monomer and (B) an acrylic compound, and (C) a phosphoric acid compound, (D) a photopolymerization initiator, (E) a colorant, and An additive may be contained. The photocurable coating material may contain a solvent, but may not contain a solvent from the viewpoint of obtaining a good protective effect. When the photocurable paint has a light shielding performance, it can be preferably used as a light shielding paint.

<Hardened product and production method thereof>
One embodiment relates to a cured product obtained by curing the cured product of the photocurable resin composition or the photocurable paint. The cured product is obtained by curing the photocurable resin composition or the photocurable paint. A hardened | cured material is provided in at least one part of the edge part of a glass base material, and can be used as a protective film which protects a glass base material.

The cured product can be obtained by a production method including a step of curing the photocurable resin composition or the photocurable paint by light irradiation. The light source described above can be used for light irradiation. For light irradiation, ultraviolet rays are preferably used. The wavelength of the ultraviolet light is not particularly limited, but is, for example, 365 nm.

<Glass base material and manufacturing method thereof>
One embodiment relates to a glass substrate in which at least a part of the end is protected by the cured product. The material of the glass substrate is not particularly limited. Examples of the glass include alkali-free glass, low alkali glass, alkali glass, and quartz glass. It may be a glass substrate chemically strengthened by an ion exchange method.

The size and thickness of the glass substrate are not particularly limited, and can be appropriately determined according to the application. For example, the photocurable resin composition is suitable for a glass substrate having a thickness of 1 mm or less, preferably 0.8 mm or less, more preferably 0.7 mm or less. Moreover, although a minimum is not specifically limited, For example, the said photocurable resin composition is suitable for the glass base material whose thickness is 0.2 mm or more, Preferably it is 0.3 mm or more, More preferably, it is 0.4 mm or more. .

For example, when a glass substrate is used for a mobile phone, the size is about 60 mm × 120 mm and the thickness is about 0.55 mm.

The end portion of the glass substrate refers to a portion including at least the side surface of the glass substrate, and may be a portion including not only the side surface of the glass substrate but also the edge of one or both surfaces of the glass substrate. FIG. 1A shows a schematic plan view of a glass substrate, and FIG. 1B shows a schematic sectional view of the glass substrate. 1 (a) and 1 (b), 1 represents a glass substrate, 2 represents a side surface of the glass substrate, and 3 represents an end of the glass substrate.

FIG. 2 shows a glass substrate provided with a cured product on the side surface. 4 is a cured product. The thickness of the cured product 4 may be uniform or non-uniform, and the maximum thickness t of the cured product 4 is not particularly limited. For example, the photocurable resin composition is suitable for a cured product having a maximum thickness t of 150 μm or more, preferably 200 μm or more, more preferably 100 μm or more. For example, the photocurable resin composition is suitable for a cured product having a maximum thickness t of 600 μm or less, preferably 500 μm or less, and more preferably 400 μm or less.

For example, when a glass substrate is used for a mobile phone, the maximum thickness t of the cured product 4 is 300 to 400 μm. A hardened | cured material may be provided in all the edge parts of a glass base material, or may be provided in a part.

The protected glass substrate is formed by applying the photocurable resin composition or the photocurable paint to at least a part of the end of the glass substrate to form a coating film, and the coating film, It can be obtained by a production method including a step of curing by light irradiation and forming a protective film. The above-described coating method can be used for coating, and the above-described light source can be used for light irradiation.

<Display device>
One embodiment relates to a display device including the glass substrate. A glass base material is used for the display part of a display apparatus. Examples of the display device include a flat panel display (FPD). Specifically, a liquid crystal display (LCD), a plasma display panel (PDP), an organic electroluminescence panel (OELP), a field emission display (FED), a cathode ray. A tube (CRT), electronic paper, etc. are mentioned.

<Mobile device>
According to one embodiment, the present invention relates to a mobile terminal including the glass substrate. A glass base material is used for the display part of a portable terminal. Examples of the portable terminal include a mobile phone, a smartphone, a personal computer, an electronic dictionary, a calculator, and a game machine.

Embodiments of the present invention will be specifically described with reference to examples. Embodiments of the present invention are not limited to the following examples.

<Preparation of photocurable resin composition>
[Example 1]
As component (A-1), 37.8 parts by mass of isobornyl acrylate, as component (A-2), 4.2 parts by mass of acryloylmorpholine, and as component (B-1), urethane acrylate compound (Art by Negami Kogyo Co., Ltd.) Resin “UN-904”) 29.0 parts by mass, urethane acrylate compound (“UN-6060S” manufactured by Negami Kogyo Co., Ltd.) 29.0 parts by mass as component (B-2), ethylene oxide modified as component (C) 0.5 parts by weight of dimethacrylate phosphate, 10.0 parts by weight of (1-hydroxycyclohexyl) phenylmethanone as component (D), and black dye as component (E) (“elixa Black850” manufactured by Orient Chemical Industries Ltd.) 0.8 parts by mass was stirred at 60 ° C. to obtain a photocurable resin composition. It was 1.8 Pa.s when the viscosity of the photocurable resin composition was measured using a B-type viscometer (rotor No. 22, rotation speed 30 rpm).

[Comparative Example 1]
18.0 parts by weight of component (A-1), 2.0 parts by weight of component (A-2), 40.0 parts by weight of component (B-1), and 40.0 parts by weight of component (B-2) A photocurable resin composition was obtained in the same manner as in Example 1 except that the composition was changed to the part. The viscosity of the photocurable resin composition was 23.4 Pa · s (rotor No. 22, rotation speed 3 rpm).

[Comparative Example 2]
Component (A-1) is 52.0 parts by mass, Component (A-2) is 6.0 parts by mass, Component (B-1) is 20.0 parts by mass, and Component (B-2) is 20.0 parts by mass. A photocurable resin composition was obtained in the same manner as in Example 1 except that the composition was changed to the part. The viscosity of the photocurable resin composition was 0.2 Pa · s (rotor No. 21, rotation speed 100 rpm).

[Viscosity of photocurable resin composition]
The viscosity was measured using a B-type viscometer (“TVB-10 type viscometer” manufactured by Toki Sangyo Co., Ltd.). The measurement conditions are described below.
Temperature: 25 ° C
Rotor: No. 21 or No. 22
Number of revolutions: Rotor no. 100 rpm when using 21
Rotor No. 3 or 30 rpm when using 22
The rotor No. When a value of less than 1 Pa · s was obtained, the rotor no. The value obtained using 21 is adopted.
In addition, rotor No. 22 is measured at a rotation speed of 30 rpm, and when a value of 10 Pa · s or less is obtained, the value obtained by measurement at a rotation speed of 30 rpm is adopted.

[(E) Colorant solubility]
The solubility of (E) colorant was confirmed by the following method.
To a 50 mL beaker, (A) 10 mL of monomer (temperature 25 ° C., mass ratio of isobornyl acrylate and acryloylmorpholine 37.8: 4.2) was added, and further 10 mg of black dye (solid content mass) was added, Stir for 1 minute using a glass rod. After stirring, the solid matter of the black dye could not be confirmed visually.

[(E) Colorant transmittance]
The irradiation light transmittance of the colorant (E) was measured by the following method.
A colorant solution was obtained by adding 0.1 parts by weight of a colorant to 100 parts by weight of the solvent. Using the resulting colorant solution, the transmittance was measured with a visible ultraviolet spectrophotometer (“UV-2400PC” manufactured by Shimadzu Corporation). The decomposition wavelength was 1 nm, and the transmittance at a wavelength of 365 nm was measured and found to be 74%.

The visible light average transmittance of the (E) colorant was measured by the following method.
Using the colorant solution prepared in the same manner as described above, the transmittance was measured every 1 nm in the wavelength range of 400 to 700 nm with a spectrocolorimeter (“CM-3700A” manufactured by Konica Minolta). The arithmetic average value of the obtained values was 38%.

About the photocurable resin composition produced in Example 1 and Comparative Examples 1 and 2, the content of each component and the viscosity are shown in Table 1.

<Evaluation>
The photocurable resin composition was applied to the end surface of the glass substrate and cured to form a protective film on the end portion of the glass substrate.

[Formation of protective film]
The photocurable resin composition was apply | coated using the dispenser apparatus with respect to the end surface of the glass substrate (60 mm x 120 mm, thickness 0.55mm) imitating a smart phone. After application, the photocurable resin composition was cured using an ultraviolet irradiation device (light source: metal halide lamp, 1,000 mJ / cm ² ).

The workability in forming the protective film, the flow-out after application, the film thickness after curing, and the like were evaluated.

[Workability]
Workability in the above coating process was evaluated according to the following criteria.
A: It was able to be applied satisfactorily without causing pulling and clogging.
B: Pulling or clogging occurred and could not be applied satisfactorily.

[Flow]
Flowing out from the completion of coating to UV irradiation was evaluated according to the following criteria.
A: The applied photocurable resin composition remained at the edge of the glass substrate without flowing out.
B: The applied photocurable resin composition flowed out.

[4-point bending strength]
The end face of the glass substrate on which the protective film was formed was scratched by dragging sandpaper (320) with a weight of 1.65 gf / mm applied as an external collision model. The drag distance was 10 mm. Place the damaged glass substrate on a 4-point bending tester (distance between upper punches 10 mm, distance between lower punches 30 mm, indentation speed 5 mm / min) so that the damaged part is located between upper punches, until the glass substrate breaks The breaking strength of was measured.

[Protective effect]
The protective effect was evaluated according to the following criteria in comparison with a glass substrate on which a protective film was formed but not damaged. The unscratched glass substrate has a 4-point bending strength of 600 MPa.
A: After scratching, the 4-point bending strength was maintained at 500 MPa or more.
B: After scratching, the 4-point bending strength decreased to less than 500 MPa.

Table 2 shows the evaluation results.

As shown in Table 2, in Example 1, the handling property was good, and it was possible to apply the photocurable resin composition to the glass end face. On the other hand, in Comparative Example 1, since the photocurable resin composition had a high viscosity, application with a dispenser was difficult, and as a result, the resin could not be applied to the glass end face. In Comparative Example 2, a sufficient amount could not be applied to the glass end face because the photocurable resin composition had a low viscosity.

For the protective effect, in Example 1, since the photocurable resin composition was sufficiently applied to the glass end face and cured, the damaged wound did not reach the glass end face, and the 4-point bending strength was maintained. It was. On the other hand, in Comparative Example 2, the photocurable resin composition was not sufficiently applied to the glass end face, and the scratched wound reached the glass end face, so that the four-point bending strength was significantly reduced.

While specific embodiments have been shown and described, various changes and substitutions may be made without departing from the spirit and scope of the invention. Accordingly, the present invention has been described by way of illustration and not limitation.

DESCRIPTION OF SYMBOLS 1 Glass base material 2 Side surface of glass base material 3 End part of glass base material 4 Hardened | cured material t Maximum thickness of hardened | cured material

Claims (9)

1. A photo-curable resin composition that is used to protect at least part of the edge of the glass substrate and has a viscosity of 0.4 to 20 Pa · s.
2. The photocurable resin composition according to claim 1, comprising a colorant.
3. A photocurable paint using the photocurable resin composition according to claim 1.
4. A cured product obtained by curing the photocurable resin composition according to claim 1 or 2 or the photocurable paint according to claim 3.
5. A glass substrate in which at least a part of the end is protected by the cured product according to claim 4.
6. A display device comprising the glass substrate according to claim 5.
7. A portable terminal comprising the glass substrate according to claim 5.
8. A method for producing a cured product, comprising a step of curing the photocurable resin composition according to claim 1 or 2 or the photocurable paint according to claim 3 by light irradiation.
9. Applying the photocurable resin composition according to claim 1 or 2 or the photocurable paint according to claim 3 to at least a part of an end of the glass substrate to form a coating film; and The manufacturing method of the protected glass base material including the process of hardening the said coating film by light irradiation and forming a protective film.

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