KR102031528B1 - Photocurable resin composition and method for manufacturing image display device - Google Patents

Abstract

It provides the photocurable resin composition which can make the elasticity modulus of the light transmissive cured resin layer low in low-temperature environment. A photocurable resin composition contains the (meth) acrylic-type oligomer which has a urethane frame | skeleton, a (meth) acrylate monomer, a polymerization initiator, and a plasticizer, The plasticizer is a polybutadiene whose 1, 2 bonding ratio is less than 80%, and 1 And 2 bond rate is at least 1 sort (s) among polyisoprene which is less than 80%.

Description

Photocurable resin composition and the manufacturing method of an image display apparatus {PHOTOCURABLE RESIN COMPOSITION AND METHOD FOR MANUFACTURING IMAGE DISPLAY DEVICE}

The present invention is to form a light-transmissive cured resin layer, which is used when an image display member and a light-transmissive optical member disposed on the surface side thereof are bonded and laminated through a light-transmissive cured resin layer to produce an image display device. It relates to a photocurable resin composition, and a manufacturing method of an image display device. This application claims priority based on Japanese Patent Application No. 2015-171790, filed September 1, 2015 in Japan, and Japanese Patent Application No. 2015-192011, filed September 29, 2015 in Japan. These applications are incorporated herein by reference.

Image display apparatuses, such as a liquid crystal display panel used for information terminals, such as a smartphone, arrange | position a photocurable resin composition between image display members, such as a liquid crystal display panel and an organic electroluminescent panel, and a light transmissive optical member, for example, , Photocurable resin composition layer is formed. Then, light is irradiated and hardened | cured to a photocurable resin composition layer, and it is set as a light transmissive cured resin layer. Thus, the image display apparatus is manufactured by bonding and laminating | stacking an image display member and a light transmissive optical member.

As a photocurable resin composition, the photocurable resin composition containing the (meth) acrylate oligomer component, the alkyl (meth) acrylate monomer component, a photoinitiator, and a plasticizer component is proposed, for example (for example, For example, refer patent document 1, 2).

Japanese Unexamined Patent Publication No. 2014-237745 International Publication No. 2013/013568

In order to obtain more sufficient adhesive strength, the glass transition temperature of a light transmissive cured resin layer (hardened | cured material of a photocurable resin composition) may be designed at the high temperature more than use temperature.

Here, as the elastic modulus of the light transmissive cured resin layer in a low temperature environment is higher, the light transmissive cured resin layer and the adherend (for example, a light transmissive optical member or an image display member) tend to be peeled off by a drop impact in a low temperature environment. I could see this. In particular, when the glass transition temperature of curable resin composition layer is high, it turned out that such a tendency is remarkable. Therefore, the photocurable resin composition which can lower the elasticity modulus of a light transmissive cured resin layer in low temperature environment is calculated | required.

This invention is proposed in view of such a conventional situation, and provides the photocurable resin composition which can make the elasticity modulus of the light transmissive cured resin layer low in low-temperature environment.

The photocurable resin composition which concerns on this invention contains the (meth) acrylic-type oligomer which has a urethane frame | skeleton, a (meth) acrylate monomer, a polymerization initiator, and a plasticizer, and a plasticizer is poly having 1, 2 bond rates less than 80%. Butadiene and at least 1 sort (s) of polyisoprene whose 1, 2 bond rates are less than 80% are contained.

Moreover, the manufacturing method of the image display apparatus which concerns on this invention is the process of apply | coating a photocurable resin composition to the surface of a light transmissive optical member, or the surface of an image display member, and an image display member and a light transmissive optical member. It has the process of bonding through a composition, and the process of hardening | curing a photocurable resin composition, A photocurable resin composition is the photocurable resin composition mentioned above.

This invention contains at least 1 sort (s) of the (meth) acrylic-type oligomer which has a urethane frame | skeleton, the (meth) acrylic-type monomer, the polybutadiene whose 1, 2 bond rates are less than 80%, and the polyisoprene whose 1, 2 bond rates are less than 80%. By using a photocurable resin composition, the elasticity modulus of the light transmissive cured resin layer in low temperature environment can be made low.

1A is an explanatory diagram showing an example of step (A1) of the method of manufacturing the image display device.
1B is an explanatory diagram showing an example of step (B1) of the method of manufacturing the image display device.
1C is an explanatory diagram showing an example of step (C1) of the method of manufacturing the image display device.
1D is an explanatory diagram showing an example of the step (C1) of the method of manufacturing the image display device.
2A is an explanatory diagram showing an example of step (A2) of the method of manufacturing the image display device.
2B is an explanatory diagram showing an example of step (A2) of the method of manufacturing the image display device.
2C is an explanatory diagram showing an example of the step (B2) of the method of manufacturing the image display device.
2D is an explanatory diagram showing an example of the step (B2) of the method of manufacturing the image display device.
2E is an explanatory diagram showing an example of the step (C2) of the method of manufacturing the image display device.
2F is an explanatory diagram showing an example of step (D2) of the method of manufacturing the image display device.
2G is an explanatory diagram showing an example of the step (D2) of the method of manufacturing the image display device.
3A is an explanatory diagram showing an example of step (A3) of the method of manufacturing the image display device.
3B is an explanatory diagram showing an example of step (A3) of the method of manufacturing the image display device.
3C is an explanatory diagram showing an example of the step (B3) of the method of manufacturing the image display device.
3D is an explanatory diagram showing an example of the step (B3) of the method of manufacturing the image display device.
3E is an explanatory diagram showing an example of the step (C3) of the method of manufacturing the image display device.
It is a perspective view which shows the glass joined body in which the light transmissive cured resin layer was formed.
FIG. 5 is a cross-sectional view taken along line AA ′ in FIG. 4.
It is sectional drawing for demonstrating the adhesive strength test of the glass joined body in which the light transmissive cured resin layer was formed.
It is a top view for demonstrating the adhesive strength test of the glass joined body in which the light transmissive cured resin layer was formed.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described in detail in the following order. In this specification, the term (meth) acrylate includes an acrylate and a methacrylate. In addition, the term (meth) acryloyl includes acryloyl and methacryloyl.

1. Photocurable resin composition

2. Manufacturing Method of Image Display Device

3. Example

<1. Photocurable Resin Composition>

The photocurable resin composition which concerns on this embodiment contains the (meth) acrylic-type oligomer (henceforth urethane acrylate oligomer (A)) which has a urethane frame | skeleton, a (meth) acrylate monomer, a polymerization initiator, and a plasticizer. And a plasticizer contains at least 1 sort (s) of polybutadiene whose 1, 2 bond rates are less than 80%, and polyisoprene whose 1, 2 bond rates are less than 80%. By using such a photocurable resin composition, the elasticity modulus of the light transmissive cured resin layer in a low temperature environment can be made low.

The photocurable resin composition contains an acryl-type oligomer and a (meth) acrylate monomer as a radically polymerizable component, and contains a urethane acrylate oligomer (A) as an acryl-type oligomer.

[Acrylic oligomer]

The acrylic oligomer is used as a reactive diluent for imparting sufficient reactivity to the photocurable resin composition, coatability, and the like. The photocurable resin composition contains a urethane acrylate oligomer (A), and may contain other acrylic oligomers other than a urethane acrylate oligomer (A) as needed.

[Urethane acrylate oligomer (A)]

Urethane acrylate oligomer (A) is an oligomer compound which has a (meth) acryloyl group and a urethane bond.

It is preferable that it is 1000-100000, as for the weight average molecular weight of a urethane acrylate oligomer (A), it is more preferable that it is 1000-70000, It is still more preferable that it is 1000-50000.

A urethane acrylate oligomer (A) is obtained by making a polyisocyanate compound, (meth) acrylate which has a hydroxyl group or an isocyanate group, and a polyol compound react, for example.

As a polyisocyanate compound, For example, isophorone diisocyanate, 2, 4-tolylene diisocyanate, 2, 6- tolylene diisocyanate, 1, 3- xylylene diisocyanate, 1, 4- xylylene diisocyanate, di And diisocyanates such as phenylmethane-4,4'-diisocyanate.

As a (meth) acrylate which has a hydroxyl group, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate and polyethyleneglycol (meth) acrylate are mentioned. As (meth) acrylate which has an isocyanate group, methacryloyloxyethyl isocyanate is mentioned, for example.

As a polyol compound, polyol compounds, such as an alkylene type, a polycarbonate type, a polyester type, or a polyether type, are mentioned, for example, Polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polycarbonate Diol, polyesterdiol, polyetherdiol, etc. are mentioned.

As a specific example of a urethane acrylate oligomer (A), For example, TEAI-1000 (made by Nippon Soda Co., Ltd.), EBECRYL230 (made by Daicel Allnex Co., Ltd.), CN9014, CN9893, CN964, CN9001, CN9788, CN9783 (above, manufactured by Satomer), UA-1 (manufactured by Light Chemical Industries, Ltd.) and the like can be used.

It is preferable that it is 5-40 mass%, and, as for content of the urethane acrylate oligomer (A) of a photocurable resin composition, it is more preferable that it is 20-40 mass%. A urethane acrylate oligomer (A) may be used individually by 1 type, and may use 2 or more types together. When using 2 or more types of urethane acrylate oligomers (A) together, it is preferable that the total amount satisfy | fills the range of the said content.

[Other (meth) acrylic oligomer]

As another (meth) acrylic-type oligomer, the (meth) acrylate-type oligomer which has polyisoprene, polybutadiene, etc. in frame | skeleton is mentioned. Specific examples of the (meth) acrylate oligomers having a polyisoprene skeleton include esterified products of maleic anhydride adducts of polyisoprene polymers and 2-hydroxyethyl methacrylate (UC102, UC203, UC-1 (above (Note) ) Kuraresa Co., Ltd.) is mentioned.

When a photocurable resin composition contains another (meth) acrylic oligomer, it is preferable that it is 1-20 mass%, and, as for content of the other (meth) acrylic oligomer in a photocurable resin composition, it is more preferable that it is 1-15 mass%. . Another (meth) acrylic oligomer may be used individually by 1 type, and may use 2 or more types together. When using 2 or more types of other (meth) acrylic-type oligomers together, it is preferable that the total amount satisfy | fills the range of the said content.

[(Meth) acrylate monomer]

Although a (meth) acrylate monomer is not specifically limited, It is preferable to contain the (meth) acrylate monomer which has a ring structure from a viewpoint of making the elasticity modulus of the light transmissive cured resin layer more low in a low-temperature environment more effectively. Moreover, the (meth) acrylate monomer may further contain another (meth) acrylate monomer.

It is preferable that the (meth) acrylate which has a ring structure has an alicyclic hydrocarbon group as a ring structure. 4-30 are preferable, as for carbon number of an alicyclic hydrocarbon group, 4-20 are more preferable, and 8-14 are more preferable. The alicyclic hydrocarbon group may have a monocyclic structure or a polycyclic structure. The alicyclic hydrocarbon group may be saturated or unsaturated. The alicyclic hydrocarbon group may have a substituent.

It is preferable that a photocurable resin composition contains the (meth) acrylate monomer (henceforth a specific (meth) acrylate monomer) represented by either of following formula (1)-(3).

[Formula 1]

(Formula (1) to (3), R each independently represents a hydrogen atom or a methyl group, X is _{-O-, -O (CH 2) n} O-, -O (CH 2 CH 2 O) n - Or -O (CH (CH ₃ ) CH ₂ O) _n- , Y is -O-, -O (CH ₂ ) _m O-, -O (CH ₂ CH ₂ O) _m- , or -O (CH (CH ₃ ) CH ₂ O) _m −, n and m each independently represent an integer of 1 to 10.

In formulas (1) to (3), R each preferably represents a hydrogen atom independently. In formulas (1) to (3), X each independently represents -O-. In Formula (3), it is preferable that Y represents -O-. In formulas (1) to (3), n and m each preferably represent an integer of 1 to 6 independently.

It is preferable that a specific (meth) acrylate monomer is a (meth) acrylate monomer represented by the said Formula (1) or Formula (2). Specifically, specific (meth) acrylate monomers are dicyclopentanyl acrylate, dicyclopentanyl methacrylate, dicyclopentenyl acrylate, dicyclopentenyl oxyethyl acrylate, and dicyclopentenyl oxyethyl meth. It is preferable that it is at least 1 type of acrylate. In particular, it is preferable that they are at least 1 sort (s) of dicyclopentanyl acrylate and dicyclopentanyl methacrylate.

Isobornyl (meth) acrylate etc. are mentioned as a specific example of the (meth) acrylate monomer which has another ring structure other than a specific (meth) acrylate monomer.

Moreover, hexanediol diacrylate etc. are mentioned as a specific example of other (meth) acrylates other than the (meth) acrylate monomer which has the above-mentioned ring structure.

15-45 mass% is preferable, and, as for content of a (meth) acrylate monomer in a photocurable resin composition, 20-40 mass% is more preferable. A (meth) acrylate monomer may be used individually by 1 type, and may use 2 or more types together. When using 2 or more types of (meth) acrylate monomers together, it is preferable that the total amount satisfy | fills the range of the said content.

Moreover, 1-35 weight% is preferable and, as for content of the (meth) acrylate monomer which has a ring structure in photocurable resin composition, 10-35 mass% is more preferable.

[Polymerization initiator]

It is preferable to use a photoradical polymerization initiator, It is more preferable to contain at least 1 sort (s) of an alkylphenone type photoinitiator and an acylphosphine oxide type photoinitiator, The polymerization initiator is an alkylphenone type photoinitiator, And it is more preferable to contain an acylphosphine oxide type photoinitiator. As an alkyl phenone system photoinitiator, 1-hydroxy cyclohexyl phenyl ketone (Irgacure 184, BASF Corporation make), 2-hydroxy-1- {4- [4- (2-hydroxy-2-methyl -Propionyl) benzyl] phenyl} -2-methyl-1-propane-1-one (Irgacure 127, manufactured by BASF) and the like can be used. As an acylphosphine oxide type photoinitiator, 2,4,6-trimethylbenzoyl diphenyl phosphine oxide (Lucirine TPO, BASF Corporation make) etc. can be used. Benzophenone, acetophenone, etc. are mentioned as another polymerization initiator.

0.1-5 mass parts is preferable with respect to a total of 100 mass parts of a radically polymerizable component, and, as for content of a photoinitiator, 0.2-3 mass parts is more preferable. By setting it as such a range, it becomes possible to prevent the hardening shortage at the time of light irradiation more effectively, and to prevent the increase of the outgas by cleavage more effectively. A polymerization initiator may be used individually by 1 type, and may use 2 or more types together. When using 2 or more types of polymerization initiators together, it is preferable that the total amount satisfy | fills the said range.

[Plasticizer]

The photocurable resin composition contains, as a plasticizer, at least one of polybutadiene having a bond rate of less than 80% and polyisoprene having a bond rate of less than 80%. By containing such a plasticizer, the photocurable resin composition can lower the elasticity modulus in the low-temperature environment of the hardened | cured material of a photocurable resin composition.

In particular, it is preferable that a photocurable resin composition contains at least 1 sort (s) of the hydrogenated substance of polybutadiene whose 1, 2 bond rates are less than 80%, and the hydrogenated substance of polyisoprene whose 1, 2 bond rates are less than 80%. Thereby, even when the glass transition temperature of a curable resin composition layer is high, the elasticity modulus in the low temperature environment of the hardened | cured material of a photocurable resin composition can be made low more effectively. Moreover, adhesive strength can also be made favorable.

75% or less is preferable and, as for the upper limit of the 1, 2 bonding ratio in the said polybutadiene, 70% or less is more preferable. Moreover, 50% or more is preferable, as for the lower limit of the 1, 2 bond ratio in the said polybutadiene, 55% or more is more preferable, and 60% or more is more preferable.

As a specific example of the polybutadiene whose 1, 2 bond rate is less than 80%, Krasol HLBH-P2000 (Hydrogenated substance of polybutadiene whose 1, 2 bond rate is 65%, the product made by Craybel Co., Ltd.), Krasol HLBH-P3000 (1, 2 bond rate The hydrogenated substance of this polybutadiene which is 65%, the product made by Craybel Co., Ltd., Krasol LBH-P2000 (The polybutadiene which the 1, 2 bond rate is 65%, the product made by Craybel Co., Ltd., Krasol LBH-P3000 (The 1, 2 bond rate is 65%. Polybutadiene, the product made by Craybelly Co., Ltd., LBH-P5000 (polybutadiene with 1, 2 bonding ratio of 65%, the product made by Craybel Co., Ltd.), etc. are mentioned.

70% or less is preferable, as for the upper limit of the 1, 2 bond ratio in the said polyisoprene, 60% or less is more preferable, 50% or less is still more preferable. Moreover, 10% or more is preferable, as for the lower limit of the 1, 2 bond ratio in the said polyisoprene, 15% or more is more preferable, 20% or more is more preferable.

Specific examples of the polyisoprene having a 1, 2 bond rate of less than 80% include EPOL (a hydrogenated product of polyisoprene having a 1, 2 bond rate of 20%, manufactured by Idemitsu Kosan Co., Ltd.), and the like.

As for the number average molecular weight of a plasticizer, 1000 or more are preferable. By setting it as such a range, bleed out can be suppressed more effectively. 20000 or less are preferable and, as for the upper limit of the number average molecular weight of a plasticizer, 10000 or less are more preferable.

The structure of the molecular terminal of a plasticizer is not specifically limited, A hydrogen atom, a hydroxyl group, an acryl group, an isocyanate group, a carboxyl group, etc. are mentioned, It is preferable that it is a hydroxyl group.

It is preferable that it is 15-50 mass%, and, as for content of the plasticizer in a photocurable resin composition, it is more preferable that it is 25-45 mass%. By setting it as such a range, the elasticity modulus of a light transmissive cured resin layer in a low temperature environment can be made low more effectively. A plasticizer may be used individually by 1 type, and may use 2 or more types together. When using 2 or more types of plasticizers together, it is preferable that the total amount satisfy | fills the said range.

Moreover, it is preferable that the sum total of content of the polybutadiene whose 1st and 2nd bonding rates are less than 80%, and the polyisoprene whose 1st and 2nd bonding rates are less than 80% in a plasticizer is 30 mass% or more, It is more preferable that it is 50 mass%, 80 It is more preferable that it is mass% or more. By setting it as such a range, the elasticity modulus of a light transmissive cured resin layer in a low temperature environment can be made low more effectively.

The photocurable resin composition may further contain other plasticizers other than the said plasticizer. As another plasticizer, a solid tackifier and a liquid oil component are mentioned. Examples of the solid tackifier include terpene resins such as terpene resins, terpene phenol resins and hydrogenated terpene resins, and rosin resins such as natural rosin, polymerized rosin, rosin ester and hydrogenated rosin. Examples of the liquid oil component include polybutadiene oil and polyisoprene oil.

[Other ingredients]

The photocurable resin composition may contain components other than the component mentioned above in the range which does not inhibit the effect which makes the elasticity modulus of the light transmissive cured resin layer low in low-temperature environment. For example, the photocurable resin composition may contain the chain transfer agent further for adjustment of molecular weight. As the chain transfer agent, for example, 2-mercaptoethanol, lauryl mercaptan, glycidyl mercaptan, mercaptoacetic acid, thioglycolic acid 2-ethylhexyl, 2,3-dimethylcapto-1-propanol, α -Methyl styrene dimer, etc. are mentioned. In addition, the photocurable resin composition may further contain adhesion improving agents, such as a silane coupling agent, antioxidant, etc.

A photocurable resin composition can be prepared by mixing each component mentioned above uniformly according to a well-known mixing method.

It is preferable that a photocurable resin composition is a liquid. When a photocurable resin composition is a liquid, the step formed in the light shielding layer formation side surface of a light shielding layer and a light transmissive optical member can be reliably canceled, for example in the manufacturing method of the image display apparatus mentioned later. Here, it is preferable that the viscosity in 25 degreeC measured with the Brookfield viscometer shows 0.01-100 Pa.s that a photocurable resin composition is a liquid.

It is preferable that the glass transition temperature of the cured resin of the photocurable resin composition is 40-80 degreeC. The measurement conditions of glass transition temperature are as having described in the Example mentioned later.

Specifically, the photocurable resin composition is 90% or more (preferably 97% or more) in the average hardening rate of the whole resin hardened | cured material obtained by photoradical polymerization by light irradiation in air | atmosphere, and the outermost surface of the resin hardened | cured material. It is preferable that the glass transition temperature at the time of hardening so that it becomes) will satisfy | fill the said range.

The reason for paying attention to the cured resin cured by radical photopolymerization in the atmosphere is that curing inhibition occurs in the cured resin due to oxygen in the atmosphere, and thus curing conditions that do not affect various properties of the cured resin due to such curing inhibition. To find them. Moreover, the reason why it is preferable to make the hardening rate of the outermost surface of hardened | cured material of resin hardened | cured is 90% or more, even if hardening inhibition generate | occur | produces on the surface of hardened | cured material, the fall of the characteristics, such as adhesiveness in the surface of hardened | cured material of resin, can be ignored practically. Because it can. Moreover, the reason why it is preferable to make the glass transition temperature of the cured resin of such hardening rate into the said range is that it can prevent it from deteriorating characteristics, such as adhesiveness and adhesive holding property, of the resin cured film formed into a film in this range. Because.

Here, a hardening rate (gel fraction) is the ratio (amount ratio) of the abundance of the (meth) acryloyl group after light irradiation with respect to the abundance of the (meth) acryloyl group in the photocurable resin composition layer before light irradiation. It is a numerical value which becomes and shows that hardening advances so that this numerical value is large. Specifically, the curing rate is the absorption peak height (X) of 1640-1620 cm <^-1> from the baseline in the FT-IR measurement chart of the photocurable resin composition layer before light irradiation, and photocurable resin after light irradiation. The absorption peak height (Y) of 1640-1620 cm <^-1> from the baseline in the FT-IR measurement chart of a composition layer (light transmissive cured resin layer) can be calculated by substitution to the following formula.

Curing rate (%) = [(X-Y) / X] × 100

The hardening rate of the surface of the hardened | cured material of the above-mentioned resin means the hardening rate measured about the resin hardened | cured material formed into a film by 10 micrometer thickness or less (for example, 5 micrometer thickness), for example. In addition, the hardening rate of the whole resin hardened | cured material means the hardening rate measured about the resin hardened | cured material formed into a film in thickness of 100 micrometers or more (for example, 200 micrometers thickness), for example.

It is preferable that the elasticity modulus in -20 degreeC of resin cured material is 3.0 E + 08 Pa or less, and, as for photocurable resin composition, it is more preferable that it is 2.9 E + 08 Pa or less. Moreover, it is preferable that the lower limit of the elasticity modulus at -20 degreeC of the resin hardened | cured material of a photocurable resin composition is 1.0 E + 08 Pa or more normally. Moreover, it is preferable that the elasticity modulus in 25 degreeC of resin cured material of a photocurable resin composition is 1.0 E + 08 Pa or less. It is preferable that the lower limit of the elasticity modulus at 25 degrees C of the resin hardened | cured material of a photocurable resin composition is 1.0 E + 06 Pa or more normally. The measurement conditions of an elasticity modulus are as having described in the Example mentioned later. Here, with resin hardened | cured material, the average hardening rate of the whole resin hardened | cured material obtained by photoradical polymerization by light irradiation in air | atmosphere, and the hardening rate of the outermost surface of the hardened | cured material of resin are 90% or more (preferably 97% or more) It means what was hardened as much as possible.

It is preferable that the transmittance | permeability of resin cured material is 90% or more, and, as for photocurable resin composition, it is more preferable that it is 92% or more. By satisfying such a range, the visibility of the image formed in the image display member which comprises an image display apparatus can be made more favorable. Here, resin hardened | cured material is synonymous with the resin hardened | cured material mentioned above.

<2. Manufacturing Method of Image Display Device>

Hereinafter, 1st-3rd embodiment of the manufacturing method of an image display apparatus is demonstrated in detail for every process, referring drawings. In the drawings, the same reference numerals denote the same components.

[First Embodiment]

[Step (A1)]

In step (A1), the photocurable resin composition is applied to the surface of the light transmissive optical member or the surface of the image display member. 1A is an explanatory diagram showing an example of step (A1) of the method of manufacturing the image display device. The light transmissive optical member 2 having the light shielding layer 1 formed on the peripheral edge portion of one side is prepared, and the photocurable resin composition 3A is applied to the surface of the light transmissive optical member 2.

The light shielding layer 1 is formed in order to improve the contrast of an image, for example. The light shielding layer 1 apply | coats the coating material colored by black etc. by the screen printing method, etc., and makes it dry and harden | cure. The thickness of the light shielding layer 1 is 5-100 micrometers normally.

The light transmissive optical member 2 should just have a light transmittance by which the image formed in the image display member can be visually recognized. For example, plate-like materials, such as glass, an acrylic resin, polyethylene terephthalate, polyethylene naphthalate, and polycarbonate, and sheet-like materials are mentioned. These materials may be subjected to hard coat treatment, antireflection treatment, or the like on one or both surfaces. Physical properties such as thickness and elastic modulus of the light transmissive optical member 2 can be appropriately determined according to the purpose of use.

[Step (B1)]

In a process (B1), an image display member and a light transmissive optical member are bonded together through a photocurable resin composition. 1B is an explanatory diagram showing an example of step (B1) of the method of manufacturing the image display device. The light transmissive optical member 2 is bonded to the image display member 6 via the photocurable resin composition 3A. Thereby, the photocurable resin composition layer 3 is formed between the image display member 6 and the light transmissive optical member 2.

[Step (C1)]

In step (C1), the photocurable resin composition is cured. 1C is an explanatory diagram showing an example of step (C1) of the method of manufacturing the image display device. Light (preferably ultraviolet rays) is irradiated and hardened | cured to the photocurable resin composition (photocurable resin composition layer 3) clamped between the image display member 6 and the light transmissive optical member 2. Thereby, the image display apparatus 10 by which the image display member 6 and the light transmissive optical member 2 were laminated | stacked is obtained through the light transmissive cured resin layer 7 as shown to FIG. 1D.

It is preferable to perform light irradiation so that the hardening rate of the light transmissive cured resin layer 7 may be 90% or more, and it is more preferable to carry out so that it may become 95% or more. By satisfying such a range, the visibility of the image formed in the image display member 6 can be made favorable. Here, a hardening rate is synonymous with the hardening rate mentioned above. The kind, output, illuminance, accumulated light amount, etc. of a light source at the time of hardening are not restrict | limited, For example, the photoradical polymerization process conditions of the (meth) acrylate by well-known ultraviolet irradiation can be employ | adopted.

Examples of the image display member 6 include a liquid crystal display panel, an organic EL display panel, a plasma display panel, a touch panel, and the like. Here, a touch panel means the image display input panel which combined the display element like a liquid crystal display panel, and the position input device like a touch pad.

The elasticity modulus at -20 degreeC and the elasticity modulus at 25 degreeC of the light transmissive cured resin layer 7 are synonymous with the elasticity modulus at -20 degreeC and the elasticity modulus at 25 degreeC, and the above-mentioned preferable range also same.

As mentioned above, although the example which apply | coated the photocurable resin composition 3A on the surface of the side where the light shielding layer 1 of the light transmissive optical member 2 was formed was demonstrated, the surface of the image display member 6 was demonstrated. You may apply | coat photocurable resin composition (3A) to it.

[2nd Embodiment]

[Step (A2)]

2A and 2B are explanatory diagrams showing an example of the step (A2) of the method of manufacturing the image display device. First, as shown to FIG. 2A, the light transmissive optical member 2 which has the light shielding layer 1 formed in the peripheral part of one side is prepared. Moreover, as shown to FIG. 2B, the photocurable resin composition is made to the surface 2a of the light transmissive optical member 2, and the light shielding layer formation side surface 2a of the light shielding layer 1 and the light transmissive optical member 2 is carried out. ) So as to cancel the step 4 formed by the thickness of the light shielding layer 1 so as to be canceled to form the photocurable resin composition layer 3. Specifically, the photocurable resin composition is applied to the entire surface of the light shielding layer forming side surface 2a of the light transmissive optical member 2 so as to be flat, including the surface of the light shielding layer 1, and a step is not generated. It is desirable to avoid. The thickness of the photocurable resin composition layer 3 is preferably 1.2 to 50 times the thickness of the light shielding layer 1, and more preferably 2 to 30 times the thickness.

Application | coating of a photocurable resin composition may be performed so that required thickness may be obtained, may be performed once, and may be performed multiple times.

[Step (B2)]

In a process (B2), a temporary hardening resin layer is formed by light-irradiating and photocuring to the photocurable resin composition layer formed in the process (A2).

2C and 2D are explanatory diagrams showing an example of the step (B2) of the method of manufacturing the image display device. As shown to FIG. 2C, the temporary cured resin layer 5 is formed by irradiating light (preferably ultraviolet-ray) to the photocurable resin composition layer 3 formed at the process (A2), and performing a temporary hardening. Performing the temporary curing of the photocurable resin composition layer 3 makes the photocurable resin composition in a state in which it does not flow remarkably from the liquid phase, and as shown in FIG. 2D, it does not fall even if it is reversed up and down, and handleability is improved. To do so. Moreover, by performing temporary hardening, the light transmissive cured resin layer 3 between the light shielding layer 1 and an image display member can be fully photocured, without removing from there between, and hardening shrinkage can also be reduced.

As for the temporary hardening of the photocurable resin composition layer 3, it is preferable to implement so that the hardening rate of the temporary hardening resin layer 5 may be 10 to 80%, It is more preferable to carry out so that it may be 40 to 80%, It is more preferable to carry out so that it may become 70 to 80%.

As long as light irradiation can be temporarily hardened so that a hardening rate may be preferably 10 to 80%, the kind, output, illuminance, amount of accumulated light, etc. of a light source will not be specifically limited, For example, by well-known ultraviolet irradiation ( The radical photopolymerization process conditions of a meth) acrylate can be employ | adopted.

Moreover, it is preferable to select the conditions which light irradiation does not generate | occur | produce the liquid flow and deformation of the temporary cured resin layer 5 at the time of the bonding operation of the process (C2) mentioned later in the range of the hardening rate mentioned above. . For example, when expressed by viscosity, it is preferable to set it as 20 Pa.s or more (corn plate rheometer, 25 degreeC, cone and plate C35 / 2, rotation speed 10rpm).

[Step (C2)]

In a process (C2), an image display member and a light transmissive optical member are bonded together through a temporary cured resin layer.

2E is an explanatory diagram showing an example of the step (C2) of the method of manufacturing the image display device. As shown in FIG. 2E, the light transmissive optical member 2 is bonded to the image display member 6 from the temporary cured resin layer 5 side. Bonding can be performed by pressing at 10-80 degreeC using a well-known crimping apparatus, for example.

[Step (D2)]

In the step (D2), light is irradiated to the temporary cured resin layer disposed between the image display member and the light transmissive optical member to thereby harden the image display member and the light transmissive optical member via the light transmissive cured resin layer. To obtain an image display device.

2F and 2G are explanatory diagrams showing an example of the step (D2) of the method of manufacturing the image display device. As shown in FIG. 2F, light (preferably ultraviolet rays) is irradiated to the temporary cured resin layer 5 sandwiched between the image display member 6 and the light transmissive optical member 2 to thereby harden it. The temporary curing of the temporary cured resin layer 5 is to fully cure the temporary cured resin layer 5 and to bond and laminate the image display member 6 and the light transmissive optical member 2. Thereby, the image display member 6 and the light transmissive optical member 2 are laminated | stacked through the light transmissive cured resin layer 7, and the image display apparatus 10 as shown in FIG. 2G is obtained. If necessary, the temporary cured resin layer 5 is irradiated with light to the temporary cured resin layer 5 between the light shielding layer 1 and the image display member 6 of the light transmissive optical member 2. You may make it harden.

It is preferable to perform this hardening so that the hardening rate of the light transmissive cured resin layer 7 may be 90% or more, and it is more preferable to carry out so that it may become 95% or more. The kind, output, illuminance, accumulated light quantity, etc. of a light source at the time of hardening are not restrict | limited, For example, the photoradical polymerization process conditions of the (meth) acrylate by well-known ultraviolet irradiation can be employ | adopted.

In 2nd Embodiment, although the example which apply | coated the photocurable resin composition to the surface 2a of the side in which the light shielding layer 1 of the light transmissive optical member 2 was formed was demonstrated, light was applied to the surface of the image display member 6 You may apply | coat curable resin composition.

[Third embodiment]

[Step (A3)]

3A and 3B are explanatory diagrams showing an example of step (A3) of the method of manufacturing the image display device. As shown to FIG. 3A, the light transmissive optical member 2 which has the light shielding layer 1 formed in the peripheral part of one side is prepared, and as shown in FIG. 3B, the surface 2a of the light transmissive optical member 2 is shown. ), The photocurable resin composition is larger than the thickness of the light shielding layer 1 so that the step 4 formed on the light shielding layer formation side surface 2a of the light shielding layer 1 and the light transmissive optical member 2 is canceled. Apply thickly.

[Step (B3)]

3C and 3D are explanatory diagrams showing an example of the step (B3) of the method of manufacturing the image display device. As shown to FIG. 3C, light (preferably ultraviolet-ray) is irradiated to the photocurable resin composition apply | coated at the process (A3), harden | cures a photocurable resin composition, and forms the light transmissive cured resin layer 7 ( 3 D). 90% or more is preferable and, as for the hardening rate of the light transmissive cured resin layer 7, 95% or more is more preferable.

[Step (C3)]

3E is an explanatory diagram showing an example of the step (C3) of the method of manufacturing the image display device. As shown in FIG. 3E, the light transmissive optical member 2 is bonded to the image display member 6 from the light transmissive cured resin layer 7 side. Thereby, the image display apparatus 10 is obtained. Bonding can be performed by the same method as the process (C2) mentioned above.

Although the case where the light transmissive optical member in which the light shielding layer was formed was demonstrated in the manufacturing method of the image display apparatus mentioned above, you may manufacture an image display apparatus using the light transmissive optical member in which the light shielding layer is not formed. .

Example

EMBODIMENT OF THE INVENTION Hereinafter, the Example of this invention is described. In the present Example, the photocurable resin composition was prepared and the image display apparatus which has the light transmissive cured resin layer using this photocurable resin composition was manufactured. And about the manufactured image display apparatus, the drop impact test at -20 degreeC, the adhesive strength at 25 degreeC, the transmittance | permeability, the elasticity modulus at -20 degreeC, the elasticity modulus at 25 degreeC, and glass transition temperature were evaluated. In addition, this invention is not limited to these Examples.

In the present Example, the following symbol was used.

[(Meth) acrylic oligomer having urethane skeleton]

TEAI-1000: Manufactured by Nippon Soda Co., Ltd.

EBECRYL230: Manufactured by Daicel Allnex Co., Ltd.

CN9014: aliphatic urethane acrylate, manufactured by Satomer

[(Meth) acrylate monomer]

FA511AS: dicyclopentenyl acrylate, manufactured by Hitachi Chemical Industry Co., Ltd.

Light acrylate IB-XA: isobornyl acrylate manufactured by Kyoeisha Chemical Co., Ltd.

HDDA: Hexanediol diacrylate, Miramer M200, manufactured by Miwon Specialty Chemical

[Plasticizer]

HLBH-P2000: hydrogenated product of polybutadiene having a 1, 2 bond ratio of 65% (both terminal hydroxyl-hydrogenated polybutadiene, Krasol HLBH-P2000), manufactured by Cray Valley

HLBH-P3000: Hydrogenated substance of polybutadiene having a 1, 2 bonding ratio of 65% (both terminal hydroxyl-hydrogenated polybutadiene, Krasol HLBH-P3000), manufactured by Cray Valley Co., Ltd.

LBH-P2000: Polybutadiene having a 1, 2 bonding ratio of 65% (both terminal hydroxyl polybutadiene, Krasol LBH-P2000), manufactured by Cray Valley

LBH-P3000: Polybutadiene having a 1, 2 bonding ratio of 65% (both terminal hydroxyl polybutadiene, Krasol LBH-P3000), manufactured by Cray Valley

EPOL: hydrogenated product of polyisoprene having 1, 2 bonding ratio of 20% (both terminal hydroxyl group hydrogenated polyisoprene), manufactured by Idemitsu Kosan Co., Ltd.

GI-1000: Hydrogenated compound of polybutadiene with a 1, 2 bond ratio of 85% or more (both terminal hydroxyl group hydrogenated polybutadiene), manufactured by Nippon Soda Co., Ltd.

GI-2000: Hydrogenated additive (both terminal hydroxyl group hydrogenated polybutadiene) of 1, 2 bond rate of 85% or more of polybutadiene, the Nippon Soda Co., Ltd. product

GI-3000: Hydrogenated additive (both terminal hydroxyl group hydrogenated polybutadiene) of 1, 2 bond rate of 85% or more, manufactured by Nippon Soda Co., Ltd.

G-1000: Polybutadiene (both terminal hydroxyl group polybutadiene) having a bond ratio of 1, 2 or more of 85% or more, manufactured by Nippon Soda Co., Ltd.

G-2000: Polybutadiene with 1, 2 bonding ratio of 85% or more (both terminal hydroxyl group polybutadiene), manufactured by Nippon Soda Co., Ltd.

[Polymerization initiator]

Irg184: 1-hydroxycyclohexylphenyl ketone, manufactured by BASF

[Preparation of photocurable resin composition]

Each component was mixed uniformly by the compounding quantity (mass part) shown in Table 1, and the photocurable resin composition of Examples 1-4 and Comparative Examples 1-3 was prepared.

EXAMPLE 1

The photocurable resin composition was prepared using 35 mass parts of TEAI-1000, 25 mass parts of FA511AS, 40 mass parts of HLBH-P2000, and 1 mass part of Irg184.

EXAMPLE 2

A photocurable resin composition was prepared in the same manner as in Example 1 except that HLBH-P2000 was changed to an equivalent amount of HLBH-P3000.

EXAMPLE 3

The photocurable resin composition was prepared like Example 1 except having changed 25 mass parts FA511AS into 20 mass parts light acrylate IB-XA and 5 mass parts HDDA.

EXAMPLE 4

A photocurable resin composition was prepared in the same manner as in Example 1 except that 40 parts by mass of HLBH-P2000 was changed to 20 parts by mass of HLBH-P3000 and 20 parts by mass of GI-1000.

[Comparative Example 1]

Except having changed HLBH-P2000 into the equivalent amount of GI-1000, it carried out similarly to Example 1, and prepared the photocurable resin composition.

[Comparative example 2]

A photocurable resin composition was prepared in the same manner as in Example 1 except that HLBH-P2000 was changed to an equivalent amount of GI-2000.

[Comparative Example 3]

A photocurable resin composition was prepared in the same manner as in Example 1 except that HLBH-P2000 was changed to an equivalent amount of GI-3000.

Each component was mixed uniformly by the compounding quantity (mass part) shown in Table 2, and the photocurable resin composition of Example 5, 6 and Comparative Examples 4 and 5 was prepared.

EXAMPLE 5

The photocurable resin composition was prepared using 25 mass parts of EBECRYL230, 30 mass parts of FA511AS, 45 mass parts of LBH-P2000, and 1 mass part of Irg184.

EXAMPLE 6

A photocurable resin composition was prepared in the same manner as in Example 5 except that the LBH-P2000 was changed to an equivalent amount of LBH-P3000.

[Comparative example 4]

A photocurable resin composition was prepared in the same manner as in Example 5 except that the LBH-P2000 was changed to an equivalent amount of G-1000.

[Comparative Example 5]

A photocurable resin composition was prepared in the same manner as in Example 5 except that the LBH-P2000 was changed to an equivalent amount of G-2000.

Each component was mixed uniformly by the compounding quantity (mass part) shown in Table 3, and the photocurable resin composition of Example 7 and the comparative example 6 was prepared.

EXAMPLE 7

The photocurable resin composition was prepared using 30 mass parts of CN9014, 35 mass parts of FA511AS, 35 mass parts of EPOL, and 1 mass part of Irg184.

[Comparative Example 6]

The photocurable resin composition was prepared using 30 mass parts of CN9014, 35 mass parts of FA511AS, 35 mass parts of GI-3000, and 1 mass part of Irg184.

[Production of image display apparatus]

Using the photocurable resin composition obtained by each Example and comparative example mentioned above, the image display apparatus was manufactured by each of the following processes.

A glass plate having a size of 45 (w) × 80 (l) × 0.4 (t) mm was prepared, and a light shielding layer having a width of 4 mm was formed on the entire area of the periphery of the glass plate so as to have a thickness of 40 μm, and thermal curing type The glass plate with a light shielding layer was prepared by apply | coating by the screen printing method and drying using the black ink of (MRX ink, Teikoku ink manufacturer).

The photocurable resin composition mentioned above was discharged to the light shielding layer formation surface of the glass plate with a light shielding layer using the resin dispenser.

On the surface where the polarizing plate of the liquid crystal display element of 40 (w) * 70 (l) mm size is laminated | stacked, the said glass plate is mounted so that the photocurable resin composition side may be a polarizing plate side, and a glass plate is carried out by the weight of the glass plate. It was affixed. The thickness of the photocurable resin composition which wetted and spread between the polarizing plate and the glass plate was 150 micrometers.

From the glass plate side, the ultraviolet-ray was irradiated at 3000 mJ / cm <2> using the ultraviolet irradiation device (UVL-7000M4-N, the product made by Ushio Lighting Co., Ltd.), the photocurable resin composition was hardened | cured, and the light transmissive cured resin layer was formed. . The curing rate of the light transmissive cured resin layer was 97%. Thereby, the liquid crystal display device in which the glass plate as a light transmissive optical member was laminated | stacked on the liquid crystal display element through the light transmissive cured resin layer was obtained.

[evaluation]

[Falling impact test]

The resultant image display device is dropped at a height of 1 m, and when there is no peeling of the interface between the light transmissive cured resin layer and the liquid crystal display element and the interface between the light transmissive cured resin layer and the glass plate, the evaluation is performed as "○", and there may be peeling. The time was evaluated as "x". The results are shown in Tables 1-3.

[Adhesive strength test]

As shown to FIG. 4, 5, the photocurable resin composition is dripped at the center part of the glass plate 31 of thickness 1mm, and is orthogonal to the glass plate 32 of thickness 1mm through the spacer 34 of 150 micrometers. It was mounted. Thereby, the glass bonding body 33 in which the photocurable resin composition layer of diameter 3mm and thickness 150micrometer was formed between glass plates 31 and 32 was obtained. Next, using an ultraviolet irradiation device, the ultraviolet-ray of 200 mW / cm <2> intensity | strength is irradiated from the glass plate 32 side so that accumulated light amount may be set to 3000 mJ / cm <2>, the photocurable resin composition layer is fully hardened and the light transmissive hardening water The strata 35 were formed. 6 and 7, the glass plate 32 located below the glass joined body 33 is fixed, and the glass plate 31 located above using the jig 36 is 5 mm in a vertical direction. It peeled at the rate of / min, and the adhesion state was evaluated on the following references | standards. Shimadzu Corporation make and AGS-X were used for the measurement of adhesive strength. The adhesive strength was calculated by measuring the stress required until the glass plate 31 and the glass plate 32 were separated at 25 ° C., and dividing the stress by the unit area of the light transmissive cured resin layer 35. When adhesive strength (25 degreeC) was 500 N / cm <2> or more, it evaluated as "(circle)", and when adhesive strength was less than 500 N / cm <2>, it evaluated as "x". The results are shown in Tables 1-3.

[Transmittance]

The transmittance | permeability of the visible light region of the light transmissive cured resin layer in an image display apparatus was measured using the ultraviolet visible spectrophotometer (The Shimadzu Corporation make, UV-2450). The results are shown in Tables 1-3.

[Elasticity rate]

The elastic modulus (-20 degreeC and 25 degreeC) of the light transmissive cured resin layer in an image display apparatus was computed using a viscoelasticity measuring apparatus. The measurement was performed in the measurement frequency of 1 Hz and a tension mode using the viscoelasticity measuring apparatus (The Seiko Instruments Co., Ltd. make, DMS6100). The results are shown in Tables 1-3.

[Glass transition temperature]

The glass transition temperature of the light transmissive cured resin layer in the image display apparatus was measured. The measurement was performed in the measurement frequency of 1 Hz and a tension mode using the viscoelasticity measuring apparatus (The Seiko Instruments Co., Ltd. make, DMS6100). The results are shown in Tables 1-3.

As in Examples 1 to 7, a (meth) acrylic oligomer having a urethane skeleton, a (meth) acrylate monomer, a polymerization initiator, polybutadiene having a 1, 2 bond rate of less than 80%, and a 1, 2 bond rate of 80% When the photocurable resin composition containing at least 1 sort (s) of less than polyisoprene was used, even if the glass transition temperature of the light transmissive resin composition layer is high, it turned out that the elasticity modulus of the light transmissive resin composition layer in low temperature environment can be made low. Moreover, it turned out that the drop impact property and transmittance | permeability in -20 degreeC are also favorable.

In particular, as in Examples 1 to 4 and 7, hydrogenated products of a (meth) acrylic oligomer having a urethane skeleton, a (meth) acrylate monomer, a polymerization initiator, and a polybutadiene having a 1, 2 bond rate of less than 80% and 1 When the photocurable resin composition containing at least 1 sort (s) of the hydrogenated substance of polyisoprene whose 2 bond rates are less than 80% was used, it was also excellent in the drop impact at -20 degreeC, and it turned out that adhesive strength is also favorable.

On the other hand, when using the photocurable resin composition which does not contain at least 1 sort (s) of polybutadiene whose 1, 2 bonding rates are less than 80%, and polyisoprene whose 1, 2 bonding rates are less than 80% like Comparative Examples 1-6, It turned out that it is difficult to lower the elasticity modulus of the light transmissive resin composition layer under the following. Moreover, it turned out that the drop impact property at -20 degreeC is also not good.

1: shading layer
2: light transmitting optical member
2a: Light-shielding layer forming side surface of light transmissive optical member
3: photocurable resin composition layer
3A: photocurable resin composition
4 step
5: temporary curing resin layer
6: image display member
7: light transmissive cured resin layer
10: image display device
31, 32: glass plate
33: glass bonded
34: spacer
35: light transmissive cured resin layer
36: jig

Claims (11)

(Meth) acrylic oligomers having a urethane skeleton,
(Meth) acrylate monomer,
A polymerization initiator,
Contains a plasticizer,
The said plasticizer contains the photocurable resin composition containing at least 1 sort (s) of polybutadiene whose 1, 2 bonding rates are less than 80%, and polyisoprene whose 1, 2 bonding rates are less than 80%. The method of claim 1,
The said plasticizer contains at least 1 sort (s) of the hydrogenated substance of polybutadiene whose 1, 2 bond rates are less than 80%, and the hydrogenated substance of polyisoprene whose 1, 2 bond rates are less than 80%. The method of claim 1,
The photocurable resin composition whose content of the said plasticizer is 15-50 mass%. The method of claim 2,
The photocurable resin composition whose sum total of content of the hydrogenated substance of polybutadiene whose 1, 2 bond rates are less than 80%, and the hydrogenated substance of polyisoprene whose 1, 2 bond rates are less than 80% is 30 mass% or more in the said plasticizer. The method of claim 1,
The photocurable resin composition in which the said (meth) acrylate monomer contains the (meth) acrylate monomer which has a ring structure. The method of claim 1,
The photocurable resin composition in which the said (meth) acrylate monomer contains the (meth) acrylate monomer represented by either of following formula (1)-(3).
[Formula 1]

(Formula (1) to (3), R each independently represents a hydrogen atom or a methyl group, X is _{-O-, -O (CH 2) n} O-, -O (CH 2 CH 2 O) n - Or -O (CH (CH ₃ ) CH ₂ O) _n- , Y is -O-, -O (CH ₂ ) _m O-, -O (CH ₂ CH ₂ O) _m- , or -O (CH (CH ₃ ) CH ₂ O) _m −, n and m each independently represent an integer of 1 to 10. The method of claim 1,
The (meth) acrylate monomers are isobornyl acrylate, isobornyl methacrylate, dicyclopentanyl acrylate, dicyclopentanyl methacrylate, dicyclopentenyl acrylate, dicyclopentenyloxyethyl acrylate, And at least one kind of dicyclopentenyloxyethyl methacrylate. The method of claim 1,
The photocurable resin composition whose content of the said (meth) acrylate monomer is 15-45 mass%. The method of claim 1,
The photocurable resin composition whose elasticity modulus in -20 degreeC of the resin cured material which hardened the said photocurable resin composition is 3.0 E + 08 Pa or less. The method of claim 1,
The photocurable resin composition whose glass transition temperature of the resin hardened | cured material which hardened the said photocurable resin composition is 40-80 degreeC. Applying the photocurable resin composition to the surface of the light transmissive optical member or the surface of the image display member;
A step of bonding the image display member and the light transmissive optical member together via the photocurable resin composition;
It has a process of hardening the said photocurable resin composition,
The said photocurable resin composition is a manufacturing method of the image display apparatus which is the photocurable resin composition of any one of Claims 1-10.