JP6387510B2 - Photocurable resin composition - Google Patents

Description

  The present invention relates to a display body and a touch panel, a display body and a front plate, or a photocurable resin composition for bonding a touch panel and a front plate, an optical display body using the same, and a method for manufacturing the optical display body.

  In recent years, in an image display device used for a smartphone or the like, a display body such as a liquid crystal display panel or an organic EL panel is directly bonded to a touch panel or a display body and a protection for reinforcement from the viewpoint of preventing visibility deterioration due to surface reflection. A front plate such as a panel or a touch panel and a front plate are bonded together. It is known to use a liquid photocurable resin composition for bonding (see Patent Documents 1 and 2).

JP 2013-95794 A JP 2013-151151 A

  The present invention solves the above-mentioned problems, and uses only a photo-curing process, and with a sufficient adhesive force, a photo-curing property capable of bonding a display body and a touch panel, a display body and a front plate, or a touch panel and a front plate. It is to provide a resin composition, and to provide an optical display using the same and a method for producing the optical display.

The present invention 1 is a photocurable resin composition for bonding a display body and a touch panel, a display body and a front plate, or a touch panel and a front plate, wherein the photocurable resin composition has a softening point of 70 to 150 ° C. It relates to a photocurable resin composition containing the hydrogenated rosin ester.
The present invention 2 relates to the photocurable resin composition of the present invention 1 containing a liquid plasticizer.
This invention 3 is related with the photocurable resin composition of this invention 1 or 2 containing a (meth) acrylate oligomer and a photoinitiator.
The present invention 4 is the present invention, wherein the (meth) acrylate oligomer is at least one selected from the group consisting of (hydrogenated) polyisoprene, (hydrogenated) polybutadiene, and a (meth) acrylate oligomer having a polyurethane structure in the skeleton. The present invention relates to the photocurable resin composition of the invention 3.
This invention 5 is related with the optical display body bonded together with the photocurable resin composition in any one of this invention 1-4.
The present invention 6 is a method for producing an optical display,
(A) The photocuring according to any one of the first to fourth aspects of the present invention is applied to any one of the substrate of the display body and the touch panel, one of the display body and the front plate, or any one of the touch panel and the front plate. Applying a conductive resin composition,
(B) a step of irradiating the substrate obtained in step (A) with energy rays (for example, ultraviolet rays) to cure the photocurable resin composition, and (C) a substrate obtained in step (B); It is related with the manufacturing method including the process of joining the board | substrate with which the photocurable resin composition was not apply | coated at the process (A).
This invention 7 is related with the manufacturing method of the optical display body of this invention 6 further including the process of irradiating a photocurable resin composition to an energy beam (for example, ultraviolet-ray) after process (D) (D).
The present invention 8 is a method for manufacturing an optical display,
(A ′) The light according to any one of the first to fourth aspects of the present invention is applied to any one of the substrate of the display body and the touch panel, one of the display body and the front plate, or any one of the touch panel and the front plate. Applying a curable resin composition;
(B ′) a step of bonding the substrate obtained in step (A ′) to the substrate to which any of the photocurable resin compositions of the present invention 1 to 4 is not applied in step (A ′), and (C ') It is related with the manufacturing method of an optical display including the process of irradiating a photocurable resin composition with an energy ray (for example, ultraviolet rays).

  According to the present invention, light that can solve the above-described problem and can bond the display body and the touch panel, the display body and the front plate, or the touch panel and the front plate with sufficient adhesive force using only the photocuring process. A curable resin composition is provided, and an optical display using the same and a method for producing the optical display are provided.

<Hydrogenated rosin ester having a softening point of 70 to 150 ° C.>
The photocurable resin composition of the present invention contains a hydrogenated rosin ester having a softening point of 70 to 150 ° C. Thereby, with the improvement of adhesive strength, the hardened | cured material can be softened and the followable | trackability to a to-be-adhered body and adhesiveness can be improved. In addition, since the carboxylic acid portion of rosin is esterified, the influence of the acid component on the adherend (for example, the wiring part of the touch panel) can be suppressed. In addition, coloring when exposed to heat can also be prevented.

  The softening point of the hydrogenated rosin ester having a softening point of 70 to 150 ° C is preferably 75 to 130 ° C, more preferably 80 to 120 ° C, from the viewpoint of adhesive strength and flexibility. The softening point is a value measured by the ring and ball method.

  In view of preventing initial coloring, the hydrogenated rosin ester having a softening point of 70 to 150 ° C. preferably has a Hazen color number of 300 or less, more preferably 200 or less. The Hazen color number is a value determined by the APHA method: Japan Oil Chemistry Association, standard oil analysis test method 2.2.1.4-1996. From the viewpoint of preventing initial coloring, the hydrogenated rosin ester having a softening point of 70 to 150 ° C. preferably has a Gardner color tone of 3 or less, more preferably 2 or less. The Gardner color tone is a value determined by taking 10 g of the target resin in a test tube and heating and melting it under a nitrogen stream and color-matching with Gardner color number standard solution manufactured by Kishida Chemical Co., Ltd.

  The hydrogenated rosin ester having a softening point of 70 to 150 ° C. may be one type or two or more types.

  The hydrogenated rosin ester having a softening point of 70 to 150 ° C. can be 5 to 70% by mass in 100% by mass of the photocurable resin composition of the present invention. If it is this range, the quantity of a reaction component is appropriate, and while favorable film property is obtained, it is advantageous also in the expression effect of adhesive strength. The hydrogenated rosin ester having a softening point of 70 to 150 ° C is preferably 10 to 60% by mass and more preferably 15 to 50% by mass in 100% by mass of the photocurable resin composition of the present invention.

<Liquid plasticizer>
The photocurable resin composition can contain a liquid plasticizer. “Liquid” means to show fluidity at 25 ° C. under atmospheric pressure. For example, it indicates a viscosity of 1000 Pa · s or less (for example, a viscosity of 0.01 to 1000 Pa · s) with a cone plate viscometer. It is done. By blending a liquid plasticizer, a flexible cured product having a low elastic modulus can be obtained.

  Examples of liquid plasticizers include phthalates such as dibutyl phthalate, diisononyl phthalate, diheptyl phthalate, di (2-ethylhexyl) phthalate, diisodecyl phthalate, butyl benzyl phthalate; dioctyl adipate, diisononyl adipate, dioctyl sebacate, sebacic acid Polyvalent carboxylic acid alkyl esters such as diisononyl and 1,2-cyclohexanedicarboxylic acid diisononyl (for example, C3 to C12 alkyl esters of polyvalent carboxylic acid); phosphate esters such as tricresyl phosphate and tributyl phosphate; trimellitic acid Esters; triethylene glycol alkyl esters of polyoxyalkylene glycols such as bis (2-ethylhexanoate) (eg di, tri or tetraethylene glycol) C3-C12 alkyl ester, etc.); rubber polymer, rubber copolymer (for example, polyisoprene, polybutadiene or polybutene, or hydrides thereof, derivatives having hydroxyl groups introduced at both ends thereof, or both ends of these hydrides. Derivatives with hydroxyl group introduced, etc.); thermoplastic elastomers; petroleum resins; alicyclic saturated hydrocarbon resins; terpene resins such as terpene resins, terpene phenol resins, modified terpene resins, hydrogenated terpene resins; Resins; disproportionated rosin ester resins, polymerized rosin ester resins, rosin ester resins such as hydrogenated (hydrogenated) rosin ester resins; xylene resins; acrylic polymers and acrylic copolymers. These shall be liquid.

  Examples of the liquid plasticizer include polyvalent carboxylic acid esters (especially diisononyl 1,2-cyclohexanedicarboxylate), rubber copolymers (especially polyisoprene, polybutadiene or polybutene, or hydrides thereof, and hydroxyl groups at both ends thereof. Introduced derivatives or derivatives in which hydroxyl groups are introduced at both ends of these hydrides), hydrogenated (hydrogenated) rosin ester resins (provided that they are liquid), xylene resins, acrylic polymers or acrylic copolymers. preferable.

  The liquid plasticizer may be used alone or in combination of two or more.

  The liquid plasticizer is 300 parts by mass or less with respect to 100 parts by mass of the hydrogenated rosin ester having a softening point of 70 to 150 ° C. from the viewpoint of strength development by blending a hydrogenated rosin ester having a softening point of 70 to 150 ° C. It can be an amount. From the viewpoint of adhesive strength and flexibility, the content is preferably 10 to 250 parts by mass, more preferably 30 to 200 parts by mass, and still more preferably 50 to 150 parts by mass.

<Photocurable resin>
The photocurable resin composition can contain a photocurable resin. The photocurable resin exhibits sufficient curability and maintains the film property of the cured product, and therefore can be 10 to 85% by mass in 100% by mass of the photocurable resin composition of the present invention. -80 mass% is preferable and 20-75 mass% is more preferable. Examples of the photocurable resin include (meth) acrylate oligomers.

  The (meth) acrylate oligomer is not particularly limited, and examples thereof include (meth) acrylate oligomers having (hydrogenated) polyisoprene, (hydrogenated) polybutadiene, or polyurethane as a skeleton. These (meth) acrylate oligomers can be used alone or in combination of two or more. Here, (hydrogenated) polyisoprene includes polyisoprene and / or hydrogenated polyisoprene, and (hydrogenated) polybutadiene includes polybutadiene and / or hydrogenated polybutadiene.

  The (meth) acrylate oligomer having a (hydrogenated) polyisoprene as a skeleton is also called a (meth) acryl-modified polyisoprene, and preferably has a molecular weight of 1000 to 100,000, more preferably 10,000 to 50,000. As a commercial item, there exists "UC" (molecular weight 25000) made from Kuraray, for example.

  The (meth) acrylate oligomer having a (hydrogenated) polybutadiene as a skeleton is also called (meth) acryl-modified polybutadiene, and preferably has a molecular weight of 500 to 100,000, more preferably 1,000 to 50,000. An example of a commercially available product is “TE2000” (molecular weight 2000) manufactured by Nippon Oil Corporation.

  The (meth) acrylate oligomer having a polyurethane as a skeleton is also called a (meth) acryl-modified polyurethane, and preferably has a molecular weight of 1000 to 100,000, more preferably 10,000 to 50,000. The (meth) acrylate oligomer having a polyurethane as a skeleton includes a polyether-based, polycarbonate-based, or polyester-based polyurethane (meth) acrylate oligomer. Examples of commercially available products include “UA” manufactured by Light Chemical Co., Ltd., “UV3630ID80” and “UV3700B” manufactured by Nippon Synthetic Chemical Industry.

  As the (meth) acrylate oligomer, a (meth) acrylate oligomer having a polyurethane as a skeleton is particularly preferable.

  The (meth) acrylate oligomer may be used alone or in combination of two or more.

<Photopolymerization initiator>
The photocurable resin composition can contain a photopolymerization initiator.

  The photopolymerization initiator is not particularly limited and is 1- [4- (2-hydroxyethoxy) phenyl] -2-hydroxy-2-methyl-1-propan-1-one, 1-hydroxy-cyclohexyl-phenyl-ketone. Benzophenone, 2,2-dimethoxy-1,2-diphenylethane-1-one, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoylphenylethoxyphosphine oxide, 2-benzyl-2 -Dimethylamino-1- (4-morpholinophenyl) butanone-1,2-hydroxy-2-methyl-1-phenyl-propan-1-one, 2-methyl-1- [4-methylthio] phenyl] -2- Morpholinopropan-1-one, benzoin methyl ether, benzoin ethyl ether, benzo Isobutyl ether, benzoin isopropyl ether, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, 2-hydroxy-2-methyl- [4- (1-methylvinyl) phenyl] propanol oligomer, 2-hydroxy- 2-methyl- [4- (1-methylvinyl) phenyl] propanol oligomer, 2-hydroxy-2-methyl-1-phenyl-1-propanone, isopropylthioxanthone, methyl o-benzoylbenzoate, [4- (methylphenyl) Thio) phenyl] phenylmethane, 2,4-diethylthioxanthone, 2-chlorothioxanthone, benzophenone, ethyl anthraquinone, benzophenone ammonium salt, thioxanthone ammonium salt, bis (2,6-dimethoxybenzoyl) 2,4,4-trimethyl-pentylphosphine oxide, bis (2,6-dimethoxybenzoyl) -2,4,4-trimethyl-pentylphosphine oxide, 2,4,6-trimethylbenzophenone, 4-methylbenzophenone, 4, 4′-bisdiethylaminobenzophenone, 1,4 dibenzoylbenzene, 10-butyl-2-chloroacridone, 2,2′bis (o-chlorophenyl) 4,5,4 ′, 5′-tetrakis (3,4, 5-trimethoxyphenyl) 1,2′-biimidazole, 2,2′bis (o-chlorophenyl) 4,5,4 ′, 5′-tetraphenyl-1,2′-biimidazole, 2-benzoylnaphthalene, 4-benzoyl biphenyl, 4-benzoyl diphenyl ether, acrylated benzophenone, bis (η5- , 4-cyclopentadien-1-yl) -bis (2,6-difluoro-3- (1H-pyrrol-1-yl) -phenyl) titanium, o-methylbenzoylbenzoate, p-dimethylaminobenzoic acid ethyl ester, Examples include p-dimethylaminobenzoic acid isoamyl ethyl ester, active tertiary amine, carbazole / phenone photopolymerization initiator, acridine photopolymerization initiator, triazine photopolymerization initiator, and benzoyl photopolymerization initiator.

  The photopolymerization initiator is preferably 1-hydroxy-cyclohexyl-phenyl-ketone, 2,4,6-trimethylbenzoylphenylethoxyphosphine oxide or the like.

  A photoinitiator may be 1 type or may use 2 or more types together.

  It is preferable that a photoinitiator is 0.1-20 mass parts with respect to 100 mass parts of photocurable resins (for example, (meth) acrylate oligomer), More preferably, it is 0.5-15 mass parts. More preferably, it is 1-10 mass parts.

<Other ingredients>
The photocurable resin composition can contain a (meth) acrylate monomer as a reaction diluent, for example, 2-ethylhexyl (meth) acrylate, n-butyl (meth) acrylate, i-butyl (meth) acrylate. Alkyl (meth) acrylates such as tert-butyl (meth) acrylate and lauryl (meth) acrylate; alkoxy-substituted alkyl (meth) acrylates such as methoxyethyl (meth) acrylate; 2-hydroxyethyl (meth) acrylate and 2-hydroxy Hydroxy-substituted alkyl (meth) acrylates such as propyl (meth) acrylate and 2-hydroxybutyl (meth) acrylate; benzyl (meth) acrylate, phenyl (meth) acrylate, etc .; ethylene glycol di (meth) acrylate, diethylene glycol Cold di (meth) acrylate, triethylene glycol di (meth) acrylate, 1,3-butylene glycol di (meth) acrylate, 1,4-butylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1, Examples include di (meth) acrylates such as 6-hexanediol di (meth) acrylate; dicyclopentenyloxyethyl (meth) acrylate, norbornene (meth) acrylate, dicyclopentanyl (meth) acrylate, and isobornyl (meth) acrylate. it can.

  As the (meth) acrylate monomer, alkyl (meth) acrylate such as lauryl (meth) acrylate, methoxyethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate and the like are preferable.

  The (meth) acrylate monomer may be used alone or in combination of two or more.

  It is preferable that a (meth) acrylate monomer is 1-250 mass parts with respect to 100 mass parts of photocurable resins (for example, (meth) acrylate oligomer), More preferably, it is 20-200 mass parts, More preferably. Is 50 to 150 parts by mass.

  The photocurable resin composition can further contain an adhesion-imparting agent. Silane coupling agents such as vinyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldisilane as adhesion promoters Ethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3- Methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxy Lan, N-2- (aminoethyl) -3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N- (1,3-dimethyl- Butylidene) propylamine, N-phenyl-3-aminopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, 3-chloropropyltrimethoxysilane, 3-mercaptopropyl, methyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, Examples thereof include bis (triethoxysilylpropyl) tetrasulfide and 3-isocyanatopropyltriethoxysilane.

  The adhesion imparting agent may be used alone or in combination of two or more.

  The adhesion-imparting agent is preferably 0.01 to 15 parts by mass, more preferably 0.1 to 10 parts by mass with respect to 100 parts by mass of the photocurable resin (for example, (meth) acrylate oligomer). More preferably, it is 1-5 mass parts.

  The photocurable resin composition can contain an antioxidant. Antioxidants include BHT, 2,4-bis- (n-octylthio) -6- (4-hydroxy-3,5-di-t-butylanilino) -1,3,5-triazine, pentaerythrityl. Tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 2,2-thio-diethylenebis [3- (3,5-di-t-butyl-4-hydroxyphenyl) Propionate], triethylene glycol-bis [3- (3-t-butyl-5-methyl-4-hydroxyphenyl) propionate], 1,6-hexanediol-bis [3- (3,5-di-t- Butyl-4-hydroxyphenyl) propionate], octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, N, N′-hexamethyle Bis (3,5-di-tert-butyl-4-hydroxy-hydrocinnamamide), 1,3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl-4- Hydroxybenzyl) benzene, tris- (3,5-di-t-butyl-4-hydroxybenzyl) -isocyanurate, octylated diphenylamine, 2,4, -bis [(octylthio) methyl] -O-cresol, isooctyl- Examples include 3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate and dibutylhydroxytoluene.

  It is preferable that an antioxidant is 0.01-15 mass parts with respect to 100 mass parts of photocurable resins (for example, (meth) acrylate oligomer), More preferably, it is 0.1-10 mass parts, More preferably, it is 1-5 mass parts.

  In the photocurable resin composition, an antifoaming agent, a pigment, a filler, a chain transfer agent, a light stabilizer, a surface tension adjusting agent, a leveling agent, an ultraviolet absorber, and an antifoam are within the range not impairing the effects of the present invention. An agent or the like can be blended.

<Method for preparing photocurable resin composition>
A photocurable resin composition can be prepared by mixing each component. The mixing method is not particularly limited, and various metals, plastic containers, stirring blades, and a stirrer can be used.

<Curing method of photocurable resin composition>
The photocurable resin composition can be cured by irradiating energy rays such as ultraviolet rays. Specific examples include light having an LED as a light source. The light source is an LED having a peak at 365 nm, an LED having a peak at 405 nm, an LED having a peak at 375 nm, an LED having a peak at 385 nm, and a peak at 395 nm. LED etc. are mentioned.

  Furthermore, the light emitted from light sources, such as a metal halide lamp, a high pressure mercury lamp, a xenon lamp, a halogen lamp, and a pulse xenon lamp, can be mentioned. These lights may be adjusted to light having a specific wavelength by passing through an optical filter. Specifically, use of an optical filter that cuts light with a wavelength of 300 nm or less and / or an optical filter that cuts light with a wavelength of 500 nm or more can be mentioned.

The irradiation method is not particularly limited. Before joining the substrates, the photocurable resin composition coating layer is cured to form a cured resin layer (for example, step (B) of the first production method described later), etc. For example, ultraviolet irradiation) can irradiate light having an intensity of 1 to 1500 mW / cm ² , for example. Irradiation can be performed so that the integrated light amount is 30 to 15000 mJ / cm ² . Integrated light quantity is preferably 50~12000mJ / cm ^2, more preferably a 100~10000mJ / cm ^2. On the other hand, after joining the substrates, a curing step is performed by energy ray irradiation (for example, ultraviolet irradiation) (for example, a first manufacturing method step (D) and a second manufacturing method step (C ′) described later). Etc.), for example, light having an intensity of 1 to 1500 mW / cm ² can be irradiated. The integrated light quantity can be varied widely depending on the curing rate of the photocurable resin to be bonded, and for example, irradiation can be performed so as to be 30 to 15000 mJ / cm ² . Strength, preferably 1~1200mW / cm ^2, more preferably 1~1000mW / cm ^2, integrated light quantity is preferably 50~12000mJ / cm ^2, more preferably a 100~10000mJ / cm ^2.

<Uses of photocurable resin composition>
The photocurable resin composition of the present invention is for bonding a display body and a touch panel, a display body and a front plate, or a touch panel and a front plate.

Examples of the front plate include glass or engineering plastic, for example, an acrylic plate (which may be single-sided or double-sided hard coat treatment or AR coat treatment), a transparent plastic plate such as a polycarbonate plate, a PET plate, or a PEN plate. The front plate can also be a protective panel.
Examples of the touch panel include a resistive film type, a capacitance type, an electromagnetic induction type, and an optical type touch panel.
Examples of the display include LCD, EL display, EL illumination, electronic paper, and plasma display.
In the present invention, the front plate, the touch panel, and the display body may have a step or may have a light shielding portion. Here, the light shielding portion refers to a portion where the photocurable resin composition applied to the adhesive surface is not exposed to energy rays (for example, ultraviolet rays) necessary for curing.

<Method for producing optical display>
The manufacturing method of the optical display body of this invention is demonstrated.
The first manufacturing method of the optical display body of the present invention includes:
(A) The process of apply | coating the photocurable resin composition of this invention to either one of a display body and a touch panel, either a display body and a front board, or one of a touch panel and a front board,
(B) a step of irradiating the substrate obtained in step (A) with energy rays (for example, ultraviolet rays) to cure the photocurable resin composition, and (C) a substrate obtained in step (B); It includes a step of bonding the substrates on which the photocurable resin composition has not been applied in the step (A).
After the step (C), as the step (D), the photocurable resin composition may be further irradiated with energy rays (for example, ultraviolet rays).

The second manufacturing method of the optical display body of the present invention includes:
(A ′) The photocurable resin composition of the present invention is applied to any one substrate of the display body and the touch panel, any one substrate of the display body and the front plate, or any one substrate of the touch panel and the front plate. Applying step,
(B ′) a step of bonding the substrate obtained in step (A ′) to the substrate to which the photocurable resin composition has not been applied in step (A ′), and (C ′) a photocurable resin composition. Irradiating energy rays (for example, ultraviolet rays),
including.

  In the first production method of the present invention, the photocurable resin composition of the present invention is applied to the surface of one substrate, and the resin composition is cured by irradiation with energy rays (for example, ultraviolet rays) and then is not applied. It is a manufacturing method of an optical display including a process of joining with a material, that is, a pre-irradiation process. Further, the second production method of the present invention is a step of bonding two substrates by energy ray (for example, ultraviolet ray) irradiation after the photocurable resin composition of the present invention is joined in a liquid state, that is, a post-irradiation step. Is a method for manufacturing an optical display.

The first manufacturing method of the optical display body of the present invention is as follows.
Step (A)
A process (A) is a process of apply | coating the photocurable resin composition of this invention to one base material of a display body and a touch panel, a display body and a front plate, or a touch panel and a front plate. By the step (A), a substrate coated with the photocurable resin composition of the present invention is obtained. The step (A) is not particularly limited, and a method using a die coater, a dispenser, screen printing, or the like can be used. Here, the viscosity of the photocurable resin composition of the present invention is not particularly limited, but is preferably 1,000 to 100,000 mPa · s, and more preferably 1,500 to 20,000 mPa · s. The base material used in the step (A) may have a step or may have a light shielding part. Since the photocurable resin composition of the present invention can be applied in a liquid state, the substrate to which the photocurable resin composition of the present invention is applied in step (A) is a substrate having a step. However, the problem of air bubbles can be avoided. Moreover, the process (A) may use the method of laminating using a release film. The thickness of a coating layer is not specifically limited, For example, it can be set as 10-500 micrometers, and 30-350 micrometers is preferable.

Process (B)
Step (B) is a step of irradiating the base material obtained in step (A) with energy rays (for example, ultraviolet rays). In the step (B), the photocurable composition can be cured by irradiation with energy rays (for example, ultraviolet rays). Regarding curing, the description in the above <Method for curing photocurable resin composition> can be applied. When a release film is used in step (A), energy rays (for example, ultraviolet rays) may be irradiated after laminating with the release film in step (B).

Process (C)
Step (C) is a step of joining the base material obtained in step (B) to the base material to which the photocurable resin composition has not been applied in step (A). For example, when the combination of the substrates is a display body and a touch panel, and the substrate on which the photocurable resin composition is applied in the step (A) is a display body, in the step (C), in the step (A) The substrate on which the photocurable resin composition is not applied is a touch panel. In the step (C), the base materials obtained in the step (B) and the base material to which the photocurable resin composition is not applied in the step (A) are bonded to each other so that the base materials are bonded to each other. be able to. Thereby, an optical display body is obtained. Moreover, when a release film is used in the step (A), the substrates are bonded to each other after the release film is peeled off in the step (C).

Process (D)
In the first production method, after the step (C), energy rays (for example, ultraviolet rays) may be further irradiated as the step (D). After joining in the step (C), energy rays (for example, ultraviolet rays) can be further irradiated in the step (D) to strengthen the adhesive force. This method is convenient because by controlling the curing rate in the step (B), if a positional deviation or the like is found after the step (C), the substrates can be peeled off and repaired. It is. Regarding curing, the description in the above <Method for curing photocurable resin composition> can be applied.

The second manufacturing method of the optical display body of the present invention is as follows.
Process (A ')
A process (A ') is a process of apply | coating the photocurable resin composition of this invention to one base material of a display body and a touch panel, a display body, a front board, or a touch panel and a front board. Step (A ′) can be performed in the same manner as in step (A).
Process (B ')
In the step (B ′), the substrate on which the photocurable resin composition obtained in the step (A ′) is applied and the substrate on which the photocurable resin composition is not applied in the step (A ′). Is a step of joining the two. For example, when the substrate in the step (A ′) is a display body and a touch panel, and the substrate to which the photocurable resin composition is applied in the step (A ′) is a display body, in the step (B ′). The substrate on which the photocurable resin composition is not applied in the step (A ′) is a touch panel. In the step (B ′), the photocurable resin composition is uncured.
Process (C ')
Step (C ′) is a step of irradiating an energy beam (for example, ultraviolet rays) to the joined body obtained through the photocurable resin composition obtained in step (B ′). When the substrate is transparent, energy rays (for example, ultraviolet rays) can be irradiated through the substrate. Thereby, a photocurable resin composition hardens | cures, a display body, a touch panel, and a front board can be adhere | attached and bonded together. Thereby, an optical display body is obtained. Regarding curing, the description in the above <Method for curing photocurable resin composition> can be applied.

  An optical display obtained by the method for producing an optical display of the present invention is also an object of the present invention.

  Hereinafter, the present invention will be described in more detail with reference to examples and comparative examples. The present invention is not limited by these examples. The indications are parts by mass and% by mass unless otherwise specified.

  The components shown in Table 1 were mixed uniformly to prepare photocurable resin compositions of Examples and Comparative Examples.

Using the obtained photocurable resin compositions of Examples and Comparative Examples, characteristics were measured as follows.
<Adhesiveness>
As described in Production Method 1 or Production Method 2 below, a sample of the laminate was prepared using the photocurable resin composition, and the substrate 1 was placed on the lower side. ) For 24 hours, and then visually observed the appearance to test whether or not peeling occurred.
○: peeling occurs ×: peeling does not occur

<< Production Method 1 >>
150 μmt of base material 1 (26 mm × 37.5 mm × 1.1 mmt, glass) prepared using three cellophane tapes (50 μmt) so that the coated portion of the photocurable resin composition is 10 mm × 10 mm. A spacer having a thickness was attached, a coating layer of the photocurable resin composition was formed using a metal squeegee, and then the spacer was removed.
The coating layer was irradiated with light under a curing condition of 3000 mJ / cm ^{2 with} a conveyor type metal halide lamp (product of Eye Graphics, 200 mW / cm ² ).
A base material 2 (26 mm × 37.5 mm × 1.1 mmt, glass) was prepared, placed on the light-irradiated coating layer, pressed and bonded to obtain a laminate.
<< Production Method 2 >>
150 μmt of base material 1 (26 mm × 37.5 mm × 1.1 mmt, glass) prepared using three cellophane tapes (50 μmt) so that the coated portion of the photocurable resin composition is 10 mm × 10 mm. A spacer having a thickness was attached, a coating layer of the photocurable resin composition was formed using a metal squeegee, and then the spacer was removed.
Using a 365 nm LED lamp (manufactured by Panasonic, UJ35), the coating layer was irradiated with light at 100 mW / cm ² to form a temporarily cured resin layer.
A base material 2 (26 mm × 37.5 mm × 1.1 mmt, glass) was prepared, placed on a light-irradiated coating layer, pressed and bonded, and then a conveyor type metal halide lamp (made by Eye Graphics, 200 mW). / Cm ² ), the substrate 2 was irradiated with light at 3000 mJ / cm ² to obtain a laminate.

<Elastic modulus>
The elastic modulus conforms to JISZ1702 and is No. Three dumbbell test pieces (thickness 1 mmt) were prepared and measured at a speed of 10 mm / min using a tensile / compression tester (Minebea, Technograph TG-2kN). Incidentally, the dumbbell specimen, a conveyor-type metal halide lamp (manufactured by Eye Graphics Co., 200 mW / cm ²⁾ was used to a photocurable resin composition was prepared from the cured product cured at 6000 mJ / cm ^2.

<Peel strength>
A spacer having a thickness of 150 μmt prepared using three cellophane tapes (50 μmt) on the base material 1 (26 mm × 75 mm × 1.1 mmt, glass) so that the coated portion of the photocurable resin composition has a width of 20 mm. After forming the coating layer of the photocurable resin composition using a metal squeegee, the substrate 2 (26 mm × 150 mm × 0.1 mmt, PET) is placed on the coating layer and bonded, and then the conveyor Using a metal halide lamp (Igraphics, 200 mW / cm ² ), light was irradiated through the substrate 1 at 3000 mJ / cm ² to obtain a peel strength measurement test piece.
The peel strength was measured at a speed of 300 mm / min using a tensile / compression tester (manufactured by Minebea, Technograph TG-2kN).

  The photocurable compositions of the examples were excellent in both the production methods 1 and 2 in that the produced laminate had good adhesiveness, and the peel strength exceeded 10 N / 20 mm. From Examples 2, 3, and 6 to 8, it was found that by using a liquid plasticizer in combination, the elastic modulus was reduced while maintaining the adhesive force. On the other hand, Comparative Example 1 containing neither a liquid plasticizer nor a hydrogenated rosin ester having a softening point of 70 to 150 ° C. was inferior in terms of adhesive strength. As shown in Comparative Examples 2 and 3, even when a hydrogenated rosin ester having a softening point of 70 to 150 ° C. was not included and a liquid plasticizer was blended, the adhesion could not be improved.

  According to the present invention, there is provided a photocurable resin composition capable of bonding a display body and a touch panel, a display body and a front plate, or a touch panel and a front plate with sufficient adhesive force using only a photocuring process. In addition, since an optical display body using the same and a method for manufacturing the optical display body are provided, industrial utility is high.

Claims (6)

A photocurable resin composition for bonding a display body and a touch panel, a display body and a front plate, or a touch panel and a front plate, wherein the photocurable resin composition has a softening point of 70 to 150 ° C. , a liquid plasticizer, hydroxy-substituted alkyl (meth) acrylate, seen including a (meth) acrylate oligomer and a photopolymerization initiator,
The liquid plasticizer is polyisoprene, polybutadiene, polybutene, polyisoprene hydride, polybutadiene hydride, polybutene hydride, a derivative in which hydroxyl groups are introduced at both ends of polyisoprene, and hydroxyl groups are introduced at both ends of polybutadiene. Derivatives, derivatives having hydroxyl groups introduced at both ends of polybutene, derivatives having hydroxyl groups introduced at both ends of polyisoprene hydride, derivatives having hydroxyl groups introduced at both ends of hydride of polybutadiene, and both ends of hydride of polybutene One or more selected from the group consisting of a derivative having a hydroxyl group introduced, diisononyl 1,2-cyclohexanedicarboxylate, hydrogenated rosin ester resin (provided that it is liquid), xylene resin, acrylic polymer and acrylic copolymer And
The photocurable resin composition whose said (meth) acrylate oligomer is a (meth) acrylate oligomer which has a polyurethane structure in frame | skeleton . The liquid plasticizer is a combination of diisononyl 1,2-cyclohexanedicarboxylate and polybutene, a combination of diisononyl 1,2-cyclohexanedicarboxylate and a derivative in which hydroxyl groups are introduced at both ends of the hydride of polybutadiene, 1,2- The photocurable resin composition according to claim 1, which is diisononyl cyclohexanedicarboxylate, a hydrogenated rosin ester resin (provided that it is liquid), a xylene resin, an acrylic polymer or an acrylic copolymer . The optical display body bonded together with the photocurable resin composition of Claim 1 or 2 . An optical display manufacturing method comprising:
(A) The photocurable resin according to claim 1 or 2 , wherein either one of the display body and the touch panel, one of the display body and the front plate, or one of the touch panel and the front plate is used. Applying the composition;
(B) The step of irradiating the substrate obtained in step (A) with energy rays to cure the photocurable resin composition, and (C) the substrate obtained in step (B), and step (A). The manufacturing method including the process of joining the board | substrate with which the photocurable resin composition was not apply | coated by this. Furthermore, the manufacturing method of Claim 4 including the process of irradiating an energy ray to a photocurable resin composition further after the process (C) (D). An optical display manufacturing method comprising:
(A ') The photo-curing property according to claim 1 or 2 on any one substrate of a display object and a touch panel, any one substrate of a display object and a front plate, or any one substrate of a touch panel and a front plate. Applying a resin composition;
(B ′) a step of bonding the substrate obtained in step (A ′) to the substrate to which the photocurable resin composition according to claim 1 or 2 is not applied in step (A ′); and (C ′). The manufacturing method of an optical display body including the process of irradiating an energy ray to a photocurable resin composition.