TW201406799A - Photocurable resin composition, image display device, and method for producing image display device - Google Patents

Abstract

A photocurable resin composition comprising (A) a compound having a structural unit derived from polybutadiene, (B) a compound represented by general formula (1), (C) a thiol compound having a group represented by general formula (II) and (D) a photopolymerization initiator, wherein (A1) a compound having a (meth)acryloyl group and also having a structural unit derived from polybutadiene is contained as the component (A). The photocurable resin composition has excellent curability, a proper viscosity and good compatibility and can be used as one of constituent materials for an image display device. (In general formula (1), R1 represents a hydrogen atom or a methyl group; R2 represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms; and n represents a numeral value of 1 to 7.) (In general formula (II), R3 and R4 independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms; q represents an integer of 0 to 3; and * represents a bonding site.)

Description

Photocurable resin composition, image display device, and image display device manufacturing method

The present invention relates to a photocurable resin composition, an image display device using the resin composition, and a method for producing the image display device, wherein the photocurable resin composition can be used to prevent image display device from rupturing and alleviating stress And impact, and excellent transparency.

As a representative image display device equipped with a panel for image display, for example, a liquid crystal display device can be mentioned. The liquid crystal display device includes an optical film such as a liquid crystal element and a polarizing plate attached to both surfaces of the liquid crystal element. The liquid crystal element is disposed by separating two glass substrates having a thickness of about 1 mm by a gap of several micrometers, and sealing the liquid crystal in the gap, and a transparent electrode, a pixel pattern, and the like are formed on the surface of the liquid crystal substrate. .

Since the above-mentioned liquid crystal display panel is thin and easily damaged, in general, in a mobile phone, a game machine, a digital camera, a car device, etc., a commonly used liquid crystal display device is provided in front of the liquid crystal display panel. A space with a transparent front panel (protective panel).

And, in recent years, video display in mobile phones, game consoles, digital cameras, car equipment, notebook computers, desktop computers, computer screens, etc. The display device is gradually equipped with a touch panel. The image display device equipped with the touch panel is a laminated structure of the protection panel, the touch panel, and the image display component, and exists between the protection panel and the touch panel, and between the touch panel and the image display component. air.

The air present in these spaces becomes the cause of light scattering, and becomes an important cause of contrast, brightness and light transmittance, and image degradation caused by image sticking.

In order to prevent such a hazard, it is proposed to replace the air with a filler such as a resin in the space portion (see, for example, Patent Documents 1 to 4). However, the filler landfill portion proposed in Patent Documents 1 to 4 has the following problems.

That is, the oil used in Patent Document 1 is difficult to prevent leakage of the seal, and may corrode the material used for the liquid crystal panel. In addition, there is a problem that the oil leaks when the protective panel is broken.

The unsaturated polyester used in Patent Document 2 is easily discolored into yellow and is not suitable for use in a liquid crystal display device.

The silicone used in Patent Document 3 has a small adhesion force and requires an additional adhesive for fixing, so that the process becomes complicated and the adhesion to the adhesive is not large, and peeling occurs when an impact is applied. Make bubbles enter such a problem.

The polymer of the acrylic monomer used in Patent Document 4 has a small adhesive force, and does not require an additional adhesive in a small machine, but an additional adhesive is required to support the front panel of the large liquid crystal display device, so that the process becomes Complex. Further, since the raw material is formed using only a single monomer, the viscosity is low and the shrinkage during curing is large, so that it is difficult to produce a large-area film on average.

Further, as a resin composition which is buried in the space of the image display device (for example, between the protective panel and the image display element, between the protective panel and the touch panel, and between the touch panel and the image display element) When a thermosetting resin composition is used, it is limited by the heat resistance temperature of the constituent members of the image display device.

Therefore, as a resin composition filled in the space of the image display device, a photocurable resin composition has been studied.

[Previous Technical Literature] (Patent Literature)

Patent Document 1: Japanese Laid-Open Patent Publication No. 05-011239

Patent Document 2: Japanese Laid-Open Patent Publication No. 03-204616

Patent Document 3: Japanese Laid-Open Patent Publication No. 06-059253

Patent Document 4: Japanese Laid-Open Patent Publication No. 2004-125868

Further, in the image display device, for the purpose of improving the contrast of the display image, a frame-shaped light blocking portion having a predetermined width is generally provided along the outer periphery of the protective panel (for example, FIGS. 1 and 2 show an image display). The liquid crystal display devices 1A and 1B of the device are provided with a protective panel 40) provided with a light shielding portion 41. The light shielding portion has a function of shielding unnecessary light in the peripheral portion of the image display panel and preventing light leakage from deteriorating in display quality.

However, in the image display device in which the protective panel is provided with the light shielding portion, when the space is filled with the photocurable resin composition, the cover is filled with the photocurable resin composition. The photocurable resin composition filled in the space of the shadow portion of the back side of the light portion (corresponding to the P portion of the first and second figures, hereinafter also referred to as "shaded portion") may generate sufficient light. Reach, hinder hardening and other issues.

For example, the protective panel is placed on the image display element (the liquid crystal display panel is assembled on the frame), and then the photocurable resin composition is filled between the members, and when the light is irradiated from the protective panel side, the light is applied. It passes through the inner side of the frame (light-shielding part) of the protective panel (corresponding to the part of the symbol Q of the first figure and the second figure, hereinafter also referred to as "light-transmitting part"), but in the frame ( In the photocurable resin composition filled in the back side portion of the light-shielding portion, light is not sufficiently irradiated, and there is a possibility that the light cannot be sufficiently cured.

If the hardening of the resin composition is insufficient, the quality of the image display device is greatly impaired, which is a major cause of the decrease in reliability.

An object of the present invention is to provide a photocurable resin composition, an image display device using the resin composition, and a method for producing the image display device, wherein the resin composition has excellent curability, and even if only the light transmitting portion is exposed, The shaded portion of the back side portion of the light-shielding portion can also be sufficiently cured (hereinafter also referred to as "hardenability in the light-shielding portion"), and has an appropriate viscosity and good compatibility.

The present inventors have found that a photocurable resin composition containing a specific component can solve the above problems and further complete the present invention.

That is, the present invention provides the following [1] to [7].

[1] A photocurable resin composition comprising: (A) a compound having a structural unit derived from polybutadiene; (B) a compound represented by the following formula (1); (C) having the following a thiol compound represented by the formula (II); and (D) a photopolymerization initiator; wherein the component (A) contains the component (A1), and the component (A1) has (methyl group) a compound having a fluorenyl group and having a structural unit derived from polybutadiene;

(In the formula (1), R ¹ represents a hydrogen atom or a methyl group, R ² represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, and n represents an integer of 1 to 7);

(R ³ and R ⁴ in the formula (II) each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, q represents an integer of 0 to 3, and * represents a bonding moiety).

[2] The photocurable resin composition according to the above [1], wherein the component (C) is a thiol compound represented by the following formula (2).

(R ³ and R ⁴ in the formula (2) each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, p represents an integer of 1 to 6, q represents an integer of 0 to 3, and A represents a p-valent value. Organic base).

[3] The photocurable resin composition according to the above [1], wherein R ² in the above formula (1) is an alkyl group having 4 to 12 carbon atoms.

[4] The photocurable resin composition according to any one of the above [1] to [3], which substantially does not contain an organic solvent, and has a viscosity at 25 ° C of 500 to 5000 mPa. s.

[5] The photocurable resin composition according to any one of the above [1], wherein the content of the component (C) is based on the total amount of the components (A) to (C). It is 3 to 30% by mass.

[6] The photocurable resin composition according to any one of the above [1], wherein the content of the component (A1) is 25 to 100 with respect to the total amount of the component (A). quality%.

The photocurable resin composition according to any one of the above [1], wherein the component (A) further contains the component (A2), and the component (A2) does not have A (meth)acrylonitrile group having a compound derived from a structural unit of polybutadiene.

[8] The photocurable resin composition according to the above [7], wherein the mass ratio of (A1) component to (A2) [(A1)/(A2)] is 25/75 to 95/5.

The photocurable resin composition according to any one of the above-mentioned items (2), wherein A in the above formula (2) is a formula (C-1) or (hereinafter) a base represented by C-2) or an alkylene group having 1 to 12 carbon atoms,

(In the formula (C-1) or (C-2), * represents a bonding moiety, and X ¹ to X ⁷ each independently represent a single bond or an alkylene group having 1 to 12 carbon atoms which may have a substituent).

[10] The photocurable resin composition according to any one of the above [1], wherein the content of the component (B) is based on the total amount of the components (A) to (C). It is 1 to 40% by mass.

[11] The photocurable resin composition according to any one of the above [1], wherein the content of the component (A) is based on the total amount of the components (A) to (C). It is 50 to 98% by mass.

[12] An image display device comprising a laminated structure, comprising: an image display device having an image display portion; a protective panel having a light shielding portion along an outer periphery; and a resin The layer is a cured product of the photocurable resin composition according to any one of the above [1] to [11], wherein the resin layer is present between the image display element and the protective panel.

[13] A device for image display, which is an image display having a laminated structure The display device includes: an image display element having an image display portion; a touch panel; a protection panel having a light shielding portion along the outer periphery; and a resin layer present on the touch panel and the foregoing The cured resin is a cured product of the photocurable resin composition according to any one of the above [1] to [11].

[14] A method of manufacturing an image display device, wherein an image display element or a touch panel having a video display unit is disposed opposite to a protective panel having a light shielding portion along an outer periphery, and then a photocurable resin is disposed. a method in which a composition is interposed between the members and the photocurable resin composition is cured to produce an image display device.

In the above-mentioned gap, the photocurable resin composition according to any one of the above [1] to [11] is light-irradiated from at least the protective panel side to form the photocurable resin. Hardening of matter.

The photocurable resin composition of the present invention is excellent in curability in a light-shielding portion, has an appropriate viscosity, and has good compatibility. Further, the cured product of the photocurable resin composition is excellent in transparency and refractive index, and has an appropriate dielectric constant.

1A, 1B‧‧‧ liquid crystal display device

1‧‧‧Image display components

10‧‧‧LCD unit

20, 22‧‧‧ polarizing plate

30‧‧‧Touch panel

31, 32‧‧‧ resin layer

40‧‧‧Protection panel

41‧‧‧Lighting Department

50‧‧‧Backlight system

P‧‧‧Back side of the sunscreen

Q‧‧‧Transmission Department

Fig. 1 is a side cross-sectional view schematically showing an embodiment of a liquid crystal display device which is an example of the image display device of the present invention.

Fig. 2 is a view schematically showing an example of the image display device of the present invention That is, an embodiment of the liquid crystal display device, that is, a side cross-sectional view schematically showing a liquid crystal display device equipped with a touch panel.

Hereinafter, the photocurable resin composition of the present invention, the method for producing an image display device using the resin composition, and the image display device will be described in more detail by way of embodiments. Further, the present invention is not limited to the embodiment.

In the present specification, "(meth)acrylate" is "acrylate" and its corresponding "methacrylate", and similarly, "(meth)acrylic resin" is "acrylic resin" and its corresponding "methacrylic acid" "Resin", "(meth)acrylonitrile" is "acryloyl" and its corresponding "methacryl".

[Photocurable resin composition]

The photocurable resin composition of the present invention (hereinafter also referred to simply as "resin composition") contains (A) a compound having a structural unit derived from polybutadiene, and (B) represented by the formula (1) The compound (C) has a thiol compound represented by the formula (2), and (D) a photopolymerization initiator, wherein the component (A) contains the component (A1), and the component (A1) The component is a compound having a (meth)acrylonitrile group and having a structural unit derived from polybutadiene. Each component will be described in detail below.

<(A) component: a compound having a structural unit derived from polybutadiene>

The resin composition of the present invention contains a compound having a structural unit derived from polybutadiene as the component (A).

(A) component is classified into (A1) component and (A2) component, (A1) The component is a compound having a (meth)acryl fluorenyl group and having a structural unit derived from polybutadiene (hereinafter also referred to as "polybutadiene (meth) acrylate"); (A2) component is not possessed (A) A compound having a propylene group but having a structural unit derived from polybutadiene, and the resin composition of the present invention contains a polybutadiene (meth) acrylate as the component (A1).

The content of the component (A1) is preferably 25% by mass or more, and more preferably 30% by mass based on the total amount of the component (A), from the viewpoint of improving the curability in the light-shielding portion of the obtained resin composition. The above is more preferably 40% by mass or more, and still more preferably 52% by mass or more.

(Component (A1): a compound having a (meth)acryl fluorenyl group and having a structural unit derived from polybutadiene)

The compound having a (meth) acrylonitrile group and having a structural unit derived from polybutadiene as the component (A1) may, for example, be a polybutadiene diol and a monoisocyanate having a (meth) acrylonitrile group. The compound obtained by the reaction of the compound.

Among the above polybutadienes, there are those having "1,4-structural unit" or "1,2-structural unit". Here, the "1,4-structural unit" of the polybutadiene is a structural unit represented by the following chemical formula (1t) or (1c), and the "1,2-structural unit" is a repeat represented by the following chemical formula (1d) unit.

The polybutadiene diol having a main 1,4-structural unit may, for example, be Poly bd R-45HT or Poly bd R-15HT (content ratio of 1,4-structural unit: 80%, manufactured by Idemitsu Kosan Co., Ltd.) ,Product name).

The polybutadiene diol having a 1,2-structural unit is exemplified by a compound represented by the following formula (1a), and specifically, for example, G-1000 (1,2-structural unit content) Ratio: 85%), G-2000 (content ratio of 1,2-structural unit: 90%) (The above is the trade name, manufactured by Japan Soda Co., Ltd.).

(In the formula (1a), n1 is an integer from 1 to 60)

In the component (A1), the content ratio of the 1,2-structural unit to the 1,4-structural unit [1,2-structural unit/1,4-structural unit] is preferably 10/90 to 98/2. More preferably 60/40~98/2, further preferably 70/30~97/3, more preferably 80/20~95/5.

Examples of the monoisocyanate compound having a (meth)acryl fluorenyl group include 2-isocyanatoethyl (meth) acrylate, 2-isocyanatopropyl (meth) acrylate, and 3- Isocyanatopropyl (meth) acrylate or the like.

Further, the reaction of the polybutadiene diol with a monoisocyanate compound having a (meth) acrylonitrile group can be carried out, for example, in the presence of a polymerization inhibitor such as p-methoxyphenol or a catalyst such as dibutyltin dilaurate. .

In the present invention, the weight average molecular weight (Mw) of the component (A1) is preferably from 1,000 to 30,000, more preferably from 2,000 to 20,000, still more preferably from 3,000 to 20,000, from the viewpoints of hardenability, flexibility, and workability. ~10,000.

Further, in the present specification, the weight average molecular weight (Mw) of the component (A) is a value obtained by conversion by a colloidal permeation chromatography (GPC) using a standard polystyrene calibration line. Further, the number average molecular weight, the weight average molecular weight, and the degree of dispersion are defined as follows when the number of molecules having the molecular weight Mi is Ni in the component (A).

(a) number average molecular weight (Mn)

Mn=Σ(N _i M _i )/Σ Ni=Σ X _i M _i (X _i = mole fraction of the molecule of molecular weight M _i = N _i /Σ N _i )

(b) Weight average molecular weight (Mw)

Mw=Σ(N _i M _i ² )/Σ NiM _i =Σ W _i M _i (W _i = weight fraction of molecules of molecular weight M _i = N _i M _i /Σ N _i M _i )

(c) Molecular weight distribution (dispersion)

Dispersion = Mw / Mn

The content of the component (A1) is preferably from 25 to 100% by mass, more preferably from 30 to 100% by mass, based on the total amount of the component (A), from the viewpoint of improving the curability in the light-shielding portion. It is preferably 40 to 100% by mass, more preferably 45 to 100% by mass.

(Component (A2): a compound having no (meth)acryl fluorenyl group and having a structural unit derived from polybutadiene)

In the resin composition of the present invention, the component (A1) may be contained as the component (A). However, from the viewpoint of curability, curing shrinkage ratio, and handleability, the component (A) preferably contains ( A1) and (A2) are compounds having a (meth)acrylonitrile group and having a structural unit derived from polybutadiene (hereinafter also referred to as "(A2) component").

The compound of the component (A2) may, for example, be a polybutadiene diol, a polybutadiene dicarboxylic acid, a maleated polybutadiene, a butadiene homopolymer, or a copolymer copolymerizable with butadiene. a compound obtained by reacting a polybutadiene diol with a compound having an isocyanate group, a compound obtained by reacting a polybutadiene diol with a compound having a carboxyl group, and reacting a polybutadiene dicarboxylic acid with a compound having a hydroxyl group The obtained compound, a compound obtained by reacting a polybutadiene dicarboxylic acid with a compound having an epoxy group, and the like.

The polybutadiene dicarboxylic acid which has a 1,2- structural unit, for example, C-1000 (content ratio of a 1,2- structural unit: 85% or more, manufactured by Nippon Soda Co., Ltd., trade name).

As a polybutadiene homopolymer mainly having a 1,2-structural unit, for example, B-1000 (content ratio of 1,2-structural unit: 85%), B-2000 (1,2-content unit content ratio: 85%), B-3000 (1,2-structural unit content ratio: 90%) (the above is a trade name, manufactured by Japan Soda Co., Ltd.).

The compound obtained by reacting the polybutadiene diol with the compound having an isocyanate group may, for example, be TEA-1000 or TE-2000 (manufactured by Nippon Soda Co., Ltd., trade name).

The compound obtained by reacting the polybutadiene dicarboxylic acid with a compound having an epoxy group is, for example, EPB13 (product name: manufactured by Nippon Soda Co., Ltd.).

The mass ratio of (A1) component to (A2) [(A1)/(A2)] is improved from the viewpoint of improving the curability in the light-shielding portion, and from the viewpoint of obtaining a resin composition having an appropriate viscosity. The ratio is preferably 25/75 to 95/5, more preferably 30/70 to 90/10, further preferably 40/60 to 80/20, more preferably 45/55 to 70/30.

When the mass ratio is 25/75 or more, the curability of the obtained resin composition in the light shielding portion can be improved. On the other hand, when the mass ratio is 95/5 or less, a resin composition having an appropriate viscosity can be obtained.

The content of the component (A) in the resin composition of the present invention is preferably from 50 to 98% by mass, more preferably from 60 to 94% by mass, based on the total amount of the components (A) to (C), further preferably 68 to 92% by mass, more preferably 80 to 92% by mass.

When the content of the component (A) is at least 50% by mass, the curability of the obtained resin composition in the light-shielding portion can be improved, and the dielectric constant can be lowered. On the other hand, when it is 98% by mass or less, the component (B) and the component (C) can be secured. The content is such that it can be used as a resin composition having an appropriate viscosity while improving the transparency of the cured product of the resin composition.

<(B) component: a compound represented by the formula (1)>

The resin composition of the present invention contains a compound represented by the following formula (1) as the component (B).

In the above formula (1), R ¹ represents a hydrogen atom or a methyl group.

Further, R ² in the above formula (1) represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms. When the carbon number of the alkyl group exceeds 12, the compatibility with the component (A) is deteriorated, and the transparency of the cured product is lowered, which is not preferable.

Therefore, R ^{2 is} preferably an alkyl group having 4 to 12 carbon atoms from the viewpoint of improving the compatibility with the component (A) and improving the curability of the obtained resin composition in the light-shielding portion. More preferably, it is an alkyl group having 5 to 11 carbon atoms, and further preferably an alkyl group having 6 to 10 carbon atoms.

Examples of the alkyl group having 1 to 12 carbon atoms include a methyl group, an ethyl group, a propyl group, an isopropyl group, a n-butyl group, a second butyl group, an isobutyl group, a tert-butyl group, a pentyl group, a hexyl group, and a hexylene group. Base, octyl, decyl, fluorenyl, eleven, twelfth, etc.

Further, the above alkyl group may be either linear or branched.

Further, at least a part of the hydrogen atoms of these alkyl groups may be, for example, a hydroxyl group, a halogen atom, an alkyl group, a cycloalkyl group, an aryl group, an arylalkyl group, a carbonyl group, an aldehyde group, an ester group, a decylamino group or an alkoxy group. , aryloxy, alkylthio, arylthio, amine, hydrazine Substituted by a group, a silyloxy group or the like.

n in the above formula (1) represents an integer of 1 to 7, and is preferably from 1 to 6, more preferably from 1 to 5, from the viewpoint of compatibility between the component (A) and the component (C). It is preferably 3 to 5.

When n exceeds 7, the compatibility of the component (A) and the component (C) is lowered, and the transparency of the cured product tends to be lowered. Moreover, the hardenability of the shade of the obtained resin composition is lowered, which is not preferable.

Further, in the present invention, n represents the average value of the number of ethylene oxide chains of the compound represented by the general formula (1).

The compound represented by the above formula (1) may, for example, be phenoxyethyl (meth) acrylate, butyl phenoxy polyethylene glycol (meth) acrylate or pentyl phenoxy poly ethane. Glycol (meth) acrylate, hexyl phenoxy polyethylene glycol (meth) acrylate, heptyl phenoxy polyethylene glycol (meth) acrylate, octyl phenoxy polyethylene glycol ( Methyl) acrylate, nonylphenoxy polyethylene glycol (meth) acrylate, nonyl phenoxy polyethylene glycol (meth) acrylate, and the like.

These compounds may be used alone or in combination of two or more.

In addition, as a commercially available product of the above-mentioned general formula (1), for example, FA-310A (manufactured by Hitachi Chemical Co., Ltd., trade name, R ¹ in the general formula (1): hydrogen atom, R ² : hydrogen atom, average value of n: compound of 4), FA-314A (manufactured by Hitachi Chemical Co., Ltd., trade name, R ¹ in the formula (1): hydrogen atom, R ² : mercapto group, n Average: 4 compounds).

The weight average molecular weight (Mw) of the component (B) is preferably 3,000 or less, more preferably 100 to 2,800, still more preferably 150 to 2,000, more preferably Good for 200~1500.

The content of the component (B) in the resin composition of the present invention is preferably from 1 to 40% by mass, more preferably from 3 to 30% by mass, based on the total amount of the components (A) to (C), further preferably 4 to 27% by mass.

When the content of the component (B) is at least 1% by mass, a resin composition having an appropriate viscosity can be obtained, and the workability at the time of coating can be improved, and the curing shrinkage ratio can be lowered. Moreover, the obtained resin composition is excellent in the hardenability in the light-shielding portion, and the transparency of the cured product is improved.

Moreover, when it is 40 mass % or less, it can suppress that the hardening shrinkage rate raises.

<Component (B2): Low molecular weight monomer having one ethylenically unsaturated group in the molecule other than the compound represented by the above formula (1)>

Further, the resin composition of the present invention may contain a low molecular weight monomer (B2) having one ethylenically unsaturated group in the molecule other than the compound represented by the above formula (1).

The low molecular weight monomer (B2) may, for example, be an alkyl (meth) acrylate represented by the following formula (3), and a compound having a (meth) acryl fluorenyl group and a hydroxyl group or an ether bond in the molecule. .

In the above formula (3), R ¹¹ represents a hydrogen atom or a methyl group, and R ¹² represents an alkyl group having 4 to 20 carbon atoms. R ¹² is preferably an alkyl group having 6 to 18 carbon atoms, more preferably an alkyl group having 8 to 16 carbon atoms, from the viewpoint of imparting flexibility.

As the alkyl (meth) acrylate represented by the above formula (3), For example, n-butyl (meth) acrylate, t-butyl (meth) acrylate, isobutyl (meth) acrylate, n-pentyl (meth) acrylate, n-octyl (methyl) Acrylate, isooctyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isodecyl (meth) acrylate, n-hexyl (meth) acrylate, stearyl (a) Acrylate, lauryl (meth) acrylate, tridecyl (meth) acrylate, and the like. These compounds may be used alone or in combination of two or more.

Examples of the compound having a (meth)acryl fluorenyl group and a hydroxyl group or an ether bond in the molecule include 2-hydroxyethyl (meth) acrylate, 1-hydroxyethyl (meth) acrylate, and 2-hydroxy propyl. Base (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 1-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 3-hydroxy butyl ( a hydroxyl group-containing (meth) acrylate such as methyl acrylate, 2-hydroxybutyl (meth) acrylate or 1-hydroxybutyl (meth) acrylate; hydroxyethyl (meth) propylene oxime a hydroxyl group-containing (meth) acrylamide such as an amine; a polyethylene glycol mono(meth)acrylate such as diethylene glycol or triethylene glycol; a polypropylene glycol mono(methyl) such as dipropylene glycol or tripropylene glycol. An acrylate, a polybutylene glycol mono(meth)acrylate such as dibutylene glycol or tributyl glycol; a (meth) acrylate containing a morpholinyl group such as acryloylmorpholine.

Among these, from the viewpoint of moisture-heat resistance and workability at the time of coating, a (meth) acrylate having a hydroxyl group and a (meth) acrylate containing a morpholinyl group are preferred, and more preferably 4 - Hydroxybutyl (meth) acrylate, acryl morphomorpholine.

These low molecular weight monomers (B2) may be used singly or in combination of two or more. The weight average molecular weight (Mw) of these low molecular weight monomers (B2) is preferably 3,000 or less, more preferably from 100 to 2,800, still more preferably from 150 to 2,000.

In addition, the content of the low molecular weight monomer (B2) is preferably 0 to 30 parts by mass, more preferably 0 to 15 parts by mass, per 100 parts by mass of the component (B).

<(C) component: a thiol compound having a group represented by the formula (II)>

The resin composition of the present invention contains a thiol compound represented by the following formula (II) as the component (C). Further, the compounds may be used singly or in combination of two or more.

R ³ and R ⁴ in the above formula (II) each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, q represents an integer of 0 to 3, and * represents a bond moiety.

R ³ and R ⁴ each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and among them, a hydrogen atom or an alkyl group having 1 to 3 carbon atoms is preferable, and a hydrogen atom or a methyl group is more preferable. Further, the above alkyl group may be either a straight chain or a branched chain.

Examples of the alkyl group having 1 to 5 carbon atoms include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, a second butyl group, an isobutyl group, a tert-butyl group, and a pentyl group.

q in the formula (II) represents an integer of 0 to 3, and preferably an integer of 1 to 2, more preferably 1.

In addition, from the viewpoint of the stability of the obtained resin composition, the thiol compound having a group represented by the above formula (II) is preferably a thiol compound represented by the following formula (2). .

R ³ and R ⁴ in the above formula (2) each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and among them, a hydrogen atom or an alkyl group having 1 to 3 carbon atoms is preferred, and hydrogen is more preferred. Atom or methyl. Further, the above alkyl group may be either linear or branched.

p in the general formula (2) represents an integer of 1 to 6, and preferably an integer of 1 to 4, more preferably an integer of 2 to 4.

q in the formula (2) represents an integer of 0 to 3, and preferably an integer of 1 to 2, more preferably 1.

In the compound represented by the above formula (2), from the viewpoint of the stability of the obtained resin composition, it is preferred that q = 1, R ³ is a methyl group, and R ⁴ is a hydrogen atom. The second-order thiol compound represented by (2a).

(In the above formula (2a), p represents an integer of 1 to 6, and A represents a p-valent organic group).

A in the general formulae (2) and (2a) represents a p-valent organic group, specifically, a 1 to 6-valent organic group.

Examples of the monovalent organic group include an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, an aryl group having 6 to 24 carbon atoms, an aralkyl group having 6 to 24 carbon atoms, and a carbonyl group ( Represents -CO-R, but R is a hydrocarbyl group (preferably an alkyl group having 1 to 6 carbon atoms), an ester group (representing -CO-OR or -O-CO-R, but R is a hydrocarbyl group (preferably carbon) Alkyl groups of 1 to 6), an amine carbenyl group, and the like.

The alkyl group having 1 to 12 carbon atoms may, for example, be a group of R ^{2 in} the above formula (1).

Examples of the cycloalkyl group having 3 to 12 carbon atoms include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a 1-adamantyl group, a 2-adamantyl group, a 1-norbornyl group, and a 2-norst.莰基等.

Examples of the aryl group having 6 to 24 carbon atoms include a phenyl group, a biphenyl group, and a naphthyl group.

Examples of the aralkyl group having 6 to 24 carbon atoms include a benzyl group, a phenethyl group, and a phenylpropyl group.

The divalent organic group may, for example, be an alkylene group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, a phenyl group, a biphenyl group or the like having 6 to 24 carbon atoms. , polyether group, polyoxyalkylene group, carbonyl group, ester group, decylamino group, amine ester group and the like.

Examples of the alkylene group having 1 to 12 carbon atoms include a methylene group, an ethylidene group, a propylidene group, an extended isopropyl group, an exobutyl group, an exobutyl group, and a pentyl group. Stretching hexyl, stretching heptyl, stretching octyl, 2-extended ethylhexyl, stretching thiol, stretching thiol, stretching eleven, extending twelve base.

Examples of the cycloalkyl group having 3 to 12 carbon atoms include a cyclopropyl group, a cyclobutene butyl group, a cyclopentylene group, a cyclohexylene group, a cyclooctyl group, a fluorenyl group, and a 1,3-extension ring. Alkyl and the like.

Examples of the extended aryl group include a stretching phenyl group such as a 1,2-phenylene group, a 1,3-phenylene group, and a 1,4-phenylene group, a stretching phenyl group, an anthranyl group, and the like.

The polyether group may, for example, be a polyethylene oxide group or a polypropylene oxide group.

The polyoxyalkylene group may, for example, be polydimethylsiloxane, polydimethoxysiloxane, polyphenylsiloxane or polymethylphenyloxane.

Examples of the organic group having 3 to 6 valences include an aliphatic hydrocarbon group having a carbon number of 1 to 12 having a 3 to 6 valence of an aliphatic chain, and an alicyclic ring having a carbon number of 3 to 12 having an alicyclic structure of 3 to 6 carbon atoms. a hydrocarbon group, a 3 to 6-valent aromatic hydrocarbon group having an aromatic ring structure of 6 to 24, and a 3 to 6-valent heterocyclic ring having a heterocyclic structure containing a hetero atom such as an oxygen atom, a nitrogen atom or a sulfur atom. Base.

Further, these organic groups A may further have a substituent.

The organic group A may have a substituent, and examples thereof include a hydroxyl group, a halogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, a carbonyl group, an aldehyde group, an ester group, a decylamino group, an alkoxy group, and an aryloxy group. An alkylthio group, an arylthio group, an amine group, a decyl group, a decyloxy group or the like.

Among these p-valent organic groups represented by A, a group represented by the following formula (C-1) or (C-2) or an alkylene group having 1 to 12 carbon atoms is preferable.

In the above (C-1) or (C-2), * represents a bonding moiety, and X ¹ to X ⁷ each independently represent a single bond or an alkylene group having 1 to 12 carbon atoms which may have a substituent. The substituent may, for example, be the same as the substituent which the above-mentioned organic group A may have.

X ¹ to X ^{7 is} preferably a single bond or an alkylene group having 1 to 8 carbon atoms, more preferably an alkylene group having 1 to 4 carbon atoms, further preferably a methylene group or an ethylidene group.

The alkylene group having 1 to 12 carbon atoms is preferably an alkylene group having 1 to 8 carbon atoms, more preferably an alkylene group having 1 to 6 carbon atoms, further preferably an alkylene group having 2 to 4 carbon atoms. .

Specific examples of the component (C) include 1,4-bis(3-mercaptobutyloxy)butane and 1,3,5-gin(3-mercaptobutyloxyethyl)-1,3. 5-triazine-2,4,6(1H,3H,5H)-trione, pentaerythritol bismuth (3-mercaptobutyrate), and the like.

These compounds may be used alone or in combination of two or more.

In addition, these compounds are available from Showa Denko Co., Ltd. in the Karenz MT series ("Karenz MT BD1", "Karenz MT NR1", "Karenz MT PE1", etc.).

The content of the component (C) in the resin composition of the present invention is obtained from The resin composition is preferably from 1 to 30% by mass, more preferably from 1 to 30% by mass, based on the total amount of the components (A) to (C) in the resin composition, from the viewpoint of the curability and the resistance to moisture and heat resistance in the light-shielding portion. 2 to 20% by mass, further preferably 3 to 12% by mass.

<(D) component: photopolymerization initiator>

The photopolymerization initiator (D) used in the present invention may, for example, be benzophenone or N,N'-tetramethyl-4,4'-diaminobenzophenone (michlerone). N,N-tetraethyl-4,4'-diaminobenzophenone, 4-methoxy-4'-dimethylaminobenzophenone, α-hydroxyisobutylbenzophenone, 2 -ethyl hydrazine, tert-butyl hydrazine, 1,4-dimethyl hydrazine, 1-chloroindole, 2,3-dichloropurine, 3-chloro-2-methylindole, 1 , 2-benzopyrene, 2-phenylindole, 1,4-naphthoquinone, 9,10-phenanthrenequinone, thioxanthone, 2-chlorothioxanthone, 1-hydroxyl ring Aromatic ketones such as hexyl benzophenone, 2,2-dimethoxy-1,2-diphenylethane-1-one, 2-hydroxy-2-methyl-1-phenylpropan-1-one a compound; a benzoin compound such as benzoin, methyl benzoin, ethyl benzoin; a benzoin ether compound such as benzoin methyl ether, benzoin ethyl ether, benzoin isobutyl ether, benzoin phenyl ether; 1-hydroxycyclohexyl benzophenone, 2-hydroxy-2 -methyl-1-phenyl-propan-1-one, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one, etc. Alpha-hydroxyalkylphenone compound; bis(2,4,6-trimethylbenzhydrazide) )-phenylphosphine oxide, bis(2,6-dimethoxybenzylidene)-2,4,4-trimethyl-pentylphosphine oxide, 2,4,6-trimethylbenzhydrazide Thiol-based phosphine oxide compound such as bis-diphenylphosphine oxide; oligo(2-hydroxy-2-methyl-1-(4-(1-methylvinyl)phenyl)acetone); β-(吖Ester compound of pyridin-9-yl)acrylic acid; An acridine compound such as phenyl acridine, 9-pyridyl acridine or 1,7-diacridine heptane; 2-(o-chlorophenyl)-4,5-diphenylimidazole dimer, 2-(o-chlorophenyl)-4,5-di(m-methoxyphenyl)imidazole dimer, 2-(o-fluorophenyl)-4,5-diphenylimidazole dimer, 2- (o-methoxyphenyl)-4,5-diphenylimidazole dimer, 2-(p-methoxyphenyl)-4,5-diphenylimidazole dimer, 2,4-di ( p-Methoxyphenyl)-5-phenylimidazole dimer, 2-(2,4-dimethoxyphenyl)-4,5-diphenylimidazole dimer, 2-(p-methyl 2,4,5-triarylimidazole dimer such as nonylphenyl)-4,5-diphenylimidazole dimer; diphenylethylenedione, 2,2-diethoxyacetophenone, Benzyl dimethyl ketal, 2-benzyl-2- dimethylamino-1-(4-morpholinylphenyl)-1-butanone, 2-methyl-1-[4- (Methylthio)phenyl]-2-morpholinyl-1-propane and the like.

These photopolymerization initiators (D) may be used singly or in combination of two or more.

Among these, from the viewpoint of suppressing discoloration of the resin composition, 1-hydroxycyclohexyl benzophenone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, and 1-[4 are preferable. An α-hydroxyalkylphenone compound such as -(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one, bis(2,4,6- Trimethyl benzhydryl)-phenylphosphine oxide, bis(2,6-dimethoxybenzylidene)-2,4,4-trimethyl-pentylphosphine oxide, 2,4,6 a mercapto phosphine oxide compound such as trimethylbenzhydryl-diphenylphosphine oxide or oligo(2-hydroxy-2-methyl-1-(4-(1-methylvinyl)phenyl) Acetone), and combinations of these.

Further, from the viewpoint of obtaining a resin composition suitable for producing a thin film sheet, bis(2,4,6-trimethylbenzylidene)-phenylphosphine oxide is preferred. Bis(2,6-dimethoxybenzylidene)-2,4,4-trimethyl-pentylphosphine oxide, 2,4,6-trimethylbenzylidene-diphenylphosphine oxide A sulfhydryl phosphine-based compound.

The content of the (D) photopolymerization initiator used in the present invention is preferably 0.05 to 10 parts by mass, based on 100 parts by mass of the total of the components (A) to (C), from the viewpoint of curability. More preferably, it is 0.08 to 7 parts by mass, further preferably 0.1 to 4 parts by mass, more preferably 0.2 to 2 parts by mass.

<Other additives>

The photocurable resin composition of the present invention can be further formulated with other additives within a range that does not impair the effects of the present invention. As another additive, a stabilizer, a plasticizer, etc. are mentioned, for example.

The stabilizer is added for the purpose of improving the stability of the photocurable resin composition, and examples thereof include triphenyl phosphite.

The plasticizer is added for the purpose of adjusting the viscosity of the photocurable resin composition, and examples thereof include a polyester-based plasticizer of a diproton acid rain polyvalent alcohol; and the molecular chain is an alkyl acrylate monomer unit and/or a Liquid acrylic resin-based plasticizer composed of alkyl acrylate monomer unit; polyether-based plasticizer such as polypropylene glycol or its derivative; amine ester plasticizer; poly-α-methylbenzene A polystyrene plasticizer such as ethylene or polystyrene.

Moreover, it is preferable that the photocurable resin composition of the present invention contains substantially no organic solvent from the viewpoint of moisture and heat resistance and suppression of generation of bubbles in the cured product.

Further, "substantially free of an organic solvent" means that an organic solvent is not intentionally added, and the characteristics are lowered without photohardening the photocurable resin composition of the present invention. At a low level, a trace amount of an organic solvent may be contained.

Specifically, the content of the organic solvent may be 1000 ppm or less, preferably 500 ppm or less, more preferably 100 ppm or less, still more preferably 10 ppm or less, and most preferably no organic matter, based on the total amount of the resin composition. Solvent (0 ppm).

Here, the "organic solvent" means an organic compound which does not have an ethylenically unsaturated group in the molecule, is liquid at 25 ° C, and has a boiling point of 250 ° C or less at an atmospheric pressure.

[Physical properties of photocurable resin composition]

The viscosity of the photocurable resin composition of the present invention at 25 ° C is preferably from 500 to 5,000 mPa from the viewpoint of suppressing leakage and handling properties. s, more preferably 1,000 to 5,000 mPa ̇ s, further preferably 2,000 to 4,000 mPa. s, more preferably 2,500~3,800mPa. s.

Further, the viscosity at 25 ° C is a value measured by a 3° cone rotor and 0.5 min ⁻¹ using an E-type viscometer, specifically, a value obtained by the measurement method described in the examples.

[Physical properties of cured product of photocurable resin composition]

The cured product of the photocurable resin composition of the present invention preferably has a light transmittance at a wavelength of 440 nm at a film thickness of 175 nm of 98% or more, more preferably 99% or more.

The refractive index of the cured product of the photocurable resin composition of the present invention is preferably from 1.45 to 1.55, more preferably from 1.47 to 1.53.

The dielectric constant of the cured product of the photocurable resin composition of the present invention at a frequency of 1 MHz is preferably from 2.5 to 3.0, more preferably from 2.7 to 2.9. The When the dielectric constant is 2.5 or more, when the resin composition of the present invention is applied to a touch panel application, the sensing performance of the touch panel can be improved. On the other hand, when the dielectric constant is 3.0 or less, it is applied to a touch panel application, and it is possible to suppress an excessive inductance and cause a malfunction.

Further, these physical property values are values obtained based on the measurement methods described in the examples.

[Image display device]

The image display device of the present invention is an image display device having a laminated structure, the laminated structure comprising: an image display element having an image display portion; a protective panel having a light shielding portion along the outer periphery; and a resin layer The resin layer is present between the image display element and the protective panel; wherein the resin layer is a cured product of the liquid photocurable resin composition.

Moreover, the image display device of the present invention is a video display device having a laminated structure, the laminated structure including: an image display device having an image display portion; a touch panel; and a protective panel having a light shielding along the outer periphery And a resin layer existing between the touch panel and the protective panel; wherein the resin layer is a cured product of the liquid photocurable resin composition.

Next, an example of the image display device will be described as a liquid crystal display device.

In the following, an example of a video display device which can be manufactured by using the photocurable resin composition of the present embodiment is a liquid crystal display device.

<LCD display device>

Fig. 1 is a side cross-sectional view schematically showing an embodiment of a liquid crystal display device which is an example of the image display device of the present invention.

The liquid crystal display device 1A shown in Fig. 1 is composed of the image display element 1. The resin layer 32 is formed by the backlight system 50, the polarizing plate 22, the liquid crystal display unit 10, and the polarizing plate 20 in this order; the resin layer 32 is provided as a liquid crystal display. The upper surface of the polarizing plate 20 on the viewing side of the device is used; and the protective panel 40 is provided on the surface of the resin layer 32. The resin layer 32 is composed of a cured product of the photocurable resin composition of the present embodiment. Further, the protective panel 40 has a light blocking portion 41 along the outer periphery of the protective panel.

In addition, FIG. 2 is a side cross-sectional view schematically showing an embodiment of a liquid crystal display device, which is an example of a liquid crystal display device, which is an example of a liquid crystal display device. The liquid crystal display device 1B shown in FIG. 2 is composed of a video display element 1, a resin layer 32, a touch panel 30, a resin layer 31, and a protective panel 40, wherein the image display element 1 is composed of a backlight system 50, The polarizing plate 22, the liquid crystal display unit 10, and the polarizing plate 20 are laminated in this order; the resin layer 32 is provided on the upper surface of the polarizing plate 20 as the viewing side of the liquid crystal display device; and the touch panel 30 is disposed on the resin layer 32. The resin layer 31 is disposed on the upper surface of the touch panel 30; and the protective panel 40 is disposed on the surface of the resin layer 31. Further, the protective panel 40 has a light blocking portion 41 along the outer periphery of the protective panel.

Further, in the liquid crystal display device of FIG. 2, the resin layer is interposed between the image display element 1 and the touch panel 30, and between the touch panel 30 and the protective panel 40, but the resin layer is interposed therebetween. Aspects can be. Moreover, when the touch panel is of the on-cell type, the touch panel is integrated with the liquid crystal display unit. As a specific example, for example, the liquid crystal display unit 10 of the liquid crystal display device of Fig. 1 is replaced with an on-cell type.

According to the liquid crystal display device shown in FIG. 1 and FIG. 2, since the cured product of the photocurable resin composition of the present invention is provided as the resin layer 31 or 32, it has impact resistance and can be obtained without image sticking. Bright and highly contrasting images.

The liquid crystal display unit 10 can be made of a liquid crystal material known in the art. Further, the control method of the liquid crystal material can be classified into a TN (Twisted Nematic) method, an STN (Super-Twisted Nematic) method, a VA (Vertical Alignment) method, an IPS (In-Place-Switching) method, etc., but in the present invention, What control method can be used for the liquid crystal display unit.

As the polarizing plates 20 and 22, a polarizing plate generally used in the art can be used. The surfaces of these polarizers can also be treated with anti-reflection, anti-fouling, hard coat, and the like. These surface treatments can be applied to one or both sides of the polarizing plate.

As the touch panel 30, a touch panel generally used in the art can be used.

The resin layers 31 and 32 may be formed to have a thickness of, for example, 0.02 mm to 3 mm. In particular, the liquid curable resin composition of the present invention can form a thick film efficiently, and is suitable for forming resin layers 31 and 32 of 0.1 mm or more.

As the protective panel 40, a general transparent substrate for optics can be used.

Examples of the transparent substrate for optics include inorganic substrates such as glass plates and quartz plates; resin substrates such as acrylic sheets and polycarbonate; and resin sheets such as thick polyester sheets. In the case where a high surface hardness is required, a glass plate, an acrylic plate or the like is preferable, and a glass plate is more preferable.

Moreover, the surface of these optical transparent substrates can also be subjected to treatment such as antireflection, antifouling, and surface hardening treatment. These surface treatments are applied to one side of the substrate or Both sides are available. Further, the substrate can be used in combination of a plurality of substrates.

Further, for the purpose of improving the contrast of the display image, the protective panel 40 made of these substrates is provided with a light blocking portion 41 having a frame shape having a predetermined width along the outer periphery of the protective panel. The light shielding portion 41 has a function of shielding unnecessary light in the peripheral portion of the image display panel and preventing light leakage from deteriorating in display quality.

The configuration of the backlight system 50 is not particularly limited, and generally includes a reflecting means such as a reflecting plate and an illumination means such as a bulb. These means of reflection and illumination means can be used by conventional means in a general image display device.

[Method of Manufacturing Image Display Device]

In the method of manufacturing the image display device of the present invention, the image display element or the touch panel having the image display unit is disposed opposite to the protective panel having the light shielding portion along the outer periphery, and then the liquid photocurability is performed. A method of producing a device for image display in which a resin composition is interposed between the gaps of the members and curing the photocurable resin composition, wherein the liquid photocurable resin composition of the present invention is interposed in the gap And at least light-irradiated from the side of the protective panel to harden it.

For example, in the liquid crystal display device 1A of Fig. 1, the image display element 1 is placed opposite to the protective panel 40 having the light shielding portion 41 along the outer periphery, and then the liquid photocurable resin composition of the present invention is placed. The resin layer 32 is formed by curing the photocurable resin composition at least from the protective panel side by light irradiation at least on the protective panel side.

Moreover, in the liquid crystal display device 1B equipped with the touch panel of FIG. 2, the image display element 1, the touch panel 30, and the protective panel 40 having the light shielding portion 41 along the outer periphery are disposed oppositely, and then Making the invention The liquid photocurable resin composition is interposed between at least the gap between the touch panel 30 and the protective panel, and is light-irradiated from at least the protective panel side to cure the photocurable resin composition to form the resin layer 31. . Further, the liquid photocurable resin composition of the present invention may be interposed between the image display element 1 and the touch panel 30, and the resin composition may be cured in the same manner to form the resin layer 32.

Here, for example, when a liquid crystal display device is manufactured using a conventional photocurable resin composition, the space is filled in a space corresponding to the back side portion of the light shielding portion 41 of the P portion of the first and second figures. The photocurable resin composition does not reach sufficient light, and hinders hardening, and the curing of the photocurable resin composition around the light-shielding portion is not sufficiently performed, and the quality of the image display device is greatly impaired, and the reliability is lowered.

However, in the method for producing an image display device of the present invention, since the photocurable resin composition of the present invention having excellent curability is used, it is not only the Q corresponding to the first and second figures when irradiated with ultraviolet rays. In the partial light transmitting portion, the back side portion (P portion) of the light shielding portion 41 where the ultraviolet rays in the vicinity of the light transmitting portion (Q portion) are not directly irradiated may be hardened. Therefore, according to the method for manufacturing an image display device of the present invention, an image display device of excellent quality can be manufactured with good productivity.

Further, as a method of allowing the photocurable resin composition to be interposed between the gaps of the members, for example, a dispenser is used, and after applying the resin composition to an image display unit, a touch panel or a protective panel, vacuum is applied ( The method is carried out by applying a photocurable resin composition to a space portion which is prepared at a predetermined interval. In addition, the light will When the curable resin composition is molded, a dam can be formed around the image display unit and the protective panel.

The light irradiation can be performed, for example, by using an ultraviolet irradiation device so as to be almost perpendicular to the filled photocurable resin composition, and the ultraviolet rays are irradiated from the side of the protective panel.

The exposure amount at this time is preferably 500 mJ/cm ² to 5000 mJ/cm ² . Also. The exposure amount is a value obtained by multiplying the illuminance which can be measured by the ultraviolet illuminometer (product name "UV-M02" (light receiver UV-36), ORC) by the irradiation time (second).

Examples of the light source for ultraviolet irradiation include a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, a metal halide lamp, and an LED bulb. Among these, a high pressure mercury lamp or a metal halide lamp is preferred.

In addition, when the light is irradiated, it can be simultaneously irradiated from the side of the protective panel and irradiated from the side. In addition, the laminate containing the photocurable resin composition can be heated or the like to promote curing.

As described above, one of the image display devices which can be produced by using the photocurable resin composition of the present invention, that is, the liquid crystal display device, has been described, but the photocurable resin of the present invention can be used. The image display device manufactured by the object is not limited to the liquid crystal display device. For example, it can also be applied to a plasma display (PDP), a cathode ray tube (CRT), a field emission display (FED), an organic EL display, a 3D display, an electronic paper, or the like.

[Examples]

Hereinafter, the present invention will be described in more detail by way of examples, but the present invention It is not limited to the following examples.

First, a synthesis example of a photocurable resin composition which can be used in the image display device to which the present invention is applied will be described below.

Further, in the following synthesis examples, the weight average molecular weight (Mw) and the number average molecular weight (Mn) are values measured by the following methods.

[Weight average molecular weight (Mw), number average molecular weight (Mn)]

The measurement was carried out using a colloidal permeation chromatography (GPC) using tetrahydrofuran (THF) as a solvent and polystyrene as a standard. The conditions for GPC are shown below.

Measuring instrument: HLC-8320GPC (product name, manufactured by Tosoh Co., Ltd.)

Analysis column: TSKgel SuperMultipore HZ-H (3 connections) (product name, manufactured by Tosoh)

Protection column: TSKguardcolumn SuperMP (HZ)-H (product name, manufactured by Tosoh)

Effervescent solution: THF

Measuring temperature: 25 ° C

[Synthesis Example 1]

(Synthesis of polybutadiene methacrylate)

In a reaction vessel equipped with a cooling tube, a thermometer, a stirring device, a dropping funnel, and an air injection tube, α,ω-polybutadiene diol (manufactured by Nippon Soda Co., Ltd., trade name "polybutadiene diol" is added. G-3000", [1, 2-structural unit / 1,4-structural unit) content ratio: 90/10, hydroxyl value = 27 mg KOH / g) 978.2 parts by mass, p-methoxyphenol 0.5 parts by mass as polymerization inhibition 0.05 parts by mass of dibutyltin dilaurate (manufactured by Tokyo Fine Chemical Co., Ltd., trade name "L101") was used as a catalyst. After that, the inside of the reactor is ventilated while passing air. After warming to 70 ° C, 20.3 parts by mass of 2-isopropy methacrylate (manufactured by Showa Denko Co., Ltd., product name "Karenz MOI") was added dropwise at 70 to 75 ° C for 1 hour. The average was dropped in to carry out the reaction.

After the completion of the dropwise addition, the reaction was allowed to proceed for 5 hours. Then, the result of IR measurement confirmed that the isocyanate disappeared, and the reaction was terminated to obtain a polybutadiene methacrylate having a methacrylinyl group at the terminal (weight average molecular weight: 7,700). The average value (the average number of functional groups) of the methacryl fluorenyl group of one molecule of the polybutadiene methacrylate was 0.5 (the value calculated from the amount of input).

[Comparative Synthesis Example 1]

(Synthesis of hydrogenated polybutadiene methacrylate)

Hydrogenated polybutadiene diol (manufactured by Nippon Soda Co., Ltd., trade name "polybutadiene diol GI-3000" in a reaction vessel equipped with a cooling tube, a thermometer, a stirring device, a dropping funnel, and an air injection tube "Hydroxyl=29 mgKOH/g) 1045.7 parts by mass and p-methoxyphenol 0.5 parts by mass as a polymerization inhibitor and dibutyltin dilaurate (manufactured by Tokyo Fine Chemical Co., Ltd., trade name "L101") as 0.05 parts by mass. catalyst. After that, the temperature was raised to 70 ° C while the air was introduced into the reactor, and then 2-methyl methacrylate was added dropwise at 70 to 75 ° C (product of Showa Denko Co., Ltd.) under the trade name "Karenz". MOI") 20.3 parts by mass, which was dropped by an average of 1 hour to carry out a reaction.

After the completion of the dropwise addition, the reaction was allowed to proceed for 5 hours. Then, the result of IR measurement confirmed that the isocyanate disappeared, and the reaction was terminated to obtain a hydrogenated polybutadiene methacrylate having a methacryl oxime group at the terminal (weight average molecular weight: 7,700). The average value of one molecule of the hydrogenated polybutadiene methacrylate (the average number of functional groups) is 0.5 (the value calculated from the input amount).

[Comparative Synthesis Example 2]

(Synthesis of hydrogenated isoprene methacrylate)

In a reaction vessel equipped with a cooling tube, a thermometer, a stirring device, a dropping funnel, and an air injection tube, a terminal hydrogenated hydrogen isoprene (manufactured by Idemitsu Kosan Co., Ltd., trade name "Epole", hydroxyl value = 51 mgKOH / g) 843.3 parts, 0.5 parts by mass of p-methoxyphenol as a polymerization inhibitor, and 0.05 parts by mass of dibutyltin dilaurate (manufactured by Tokyo Fine Chemical Co., Ltd., trade name "L101") as a catalyst. After that, the temperature was raised to 70 ° C while the air was introduced into the reactor, and then 2-methyl methacrylate was added dropwise at 70 to 75 ° C (product of Showa Denko Co., Ltd.) under the trade name "Karenz". MOI") 20.3 parts by mass, which was dropped by an average of 1 hour to carry out a reaction.

After the completion of the dropwise addition, the reaction was allowed to proceed for 5 hours. Then, the result of IR measurement confirmed that the isocyanate disappeared, and the reaction was terminated to obtain a hydrogenated isoprene methacrylate having a methyl methacrylate group at the terminal (weight average molecular weight: 7,700). The average value (the average number of functional groups) of the methacryl fluorenyl group of one molecule of the hydrogenated isoprene methacrylate was 0.5 (the value calculated from the input amount).

[Comparative Synthesis Example 3]

(Synthesis of propylene glycol acrylate [PPGUA])

In a reaction vessel equipped with a cooling tube, a thermometer, a stirring device, a dropping funnel, and an air injection tube, 155 parts by mass of polypropylene glycol (molecular weight: 2,000), 17.9 parts by mass of 2-hydroxyethyl acrylate, and p-methoxyphenol 0.5 were added. The mass part was used as a polymerization inhibitor and 0.05 parts by mass of dibutyltin dilaurate as a catalyst. After that, the temperature inside the reactor was increased to 70 ° C while passing air, and 70 At a temperature of ~75 ° C, 32.4 parts by mass of 2,2,4-trimethylhexamethylene diisocyanate was added dropwise thereto, and the mixture was dropped on the average over 2 hours to carry out a reaction.

After completion of the dropwise addition, the reaction was allowed to proceed for 5 hours, and after the result of IR measurement, it was confirmed that the isocyanate disappeared, and the reaction was terminated to obtain propylene glycol acrylate [PPGUA] which was obtained by using polypropylene glycol and trimethylhexamethylene diisocyanate as repeating units. And having an ethylenically unsaturated bond at both ends. The average number of ethylenically unsaturated bonds per molecule of the propylene glycol acrylate is 2.0 (calculated from the amount of input).

[Examples 1 to 8 and Comparative Examples 1 to 9]

The components (A) to (D) were blended and mixed by the mixing ratios shown in Tables 1 and 2 to prepare photocurable resin compositions of Examples 1 to 8 and Comparative Examples 1 to 9. Further, in Tables 1 and 2, the unit of the numerical values of the components (A) to (D) is a part by mass (solid content ratio).

Further, the compounds used as the respective components in Tables 1 and 2 are as follows.

(A1) component

"Synthesis Example 1": Polybutadiene methacrylate obtained in Synthesis Example 1.

Substituted compound of component (A1)

"Comparative Synthesis Example 1": The hydrogenated polybutadiene methacrylate obtained in Synthesis Example 1 was compared.

"UC-102": Kuraray (share) system, trade name. It is a compound having a structural unit derived from a methacryl fluorenyl group or a polyisoprene represented by the following general formula (a) (n=2 in the following general formula (a), and a number average molecular weight of 17,000).

"Comparative Synthesis Example 2": Comparative hydrogenated isoprene A obtained in Synthesis Example 2 Acrylate.

"Comparative Synthesis Example 3": The propylene glycol acrylate obtained in Synthesis Example 3 was compared.

(A2) component

"RICON 156": Made by Cray Valley, the trade name. Polybutadiene homopolymer (number average molecular weight 1400).

(B) component

"FA-314A": Hitachi Chemical Co., Ltd., trade name. In the above formula (1), R ¹ is a hydrogen atom, R ² is a fluorenyl group, and a compound having an average value of n of 4 (Mw: 452).

(B) Substituting compounds

"FA-512AS": Hitachi Chemical Co., Ltd., trade name. Dicyclopentenyloxyethyl acrylate.

"FA-318A": Hitachi Chemical Co., Ltd., trade name. In the above formula 1, R ¹ is a hydrogen atom, R ² is a fluorenyl group, and the average value of n is 8 .

"ACMO": acryloyl morpholine.

"EHA": 2-ethylhexyl acrylate.

"LA": lauryl acrylate.

(C) component

"PE1": Showa Denko (share) system, trade name. Pentaerythritol oxime (3-mercaptobutyrate) represented by the following formula (c1).

"BD1": Showa Denko (share) system, trade name. 1,4-bis(3-mercaptobutyloxy)butane represented by the following formula (c2).

"NR1" Showa Denko (share) system, trade name. 1,3,5-gin(3-mercaptobutyloxyethyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-three represented by the following formula (c3) ketone.

(D) component

"TPO": 2,4,6-trimethylbenzimidyl-diphenylphosphine oxide (maximum absorption wavelength: 380 nm) manufactured by BASF Corporation.

The resin composition obtained in each of the examples and the comparative examples and the cured transparent sheet thereof were subjected to the following tests. The test results are shown in Tables 1 and 2.

(viscosity)

The viscosity (mPa.s) of the resin composition obtained in each of the examples and the comparative examples at 25 ° C was measured at 0.5 min ^-1 using an E-type viscometer and a 3° cone rotor.

(compatibility)

The resin composition obtained in each of the examples and the comparative examples was filled in a glass bottle, and the compatibility was visually confirmed and evaluated based on the following criteria.

A: The resin composition is transparent and has good compatibility.

F: The resin composition was cloudy and had poor compatibility.

(transmittance at a wavelength of 440 nm)

The resin composition obtained in each of the examples and the comparative examples was dropped on a PET (polyethylene terephthalate) film (manufactured by Toyobo Co., Ltd., product name "A4100", 86 mm × 56 mm × 100 μm). The film thickness of the resin composition after hardening of the same PET film by a spacer of 175 μm was 175 μm. Then, an ultraviolet ray irradiation device (product name "ELM-3000B-6N" manufactured by ORC Co., Ltd.) was used for one of the PET sheets, and ultraviolet rays of 2,000 mJ/cm ^{2 were} irradiated to cure the resin composition to produce a transparent sheet (cured material). ).

Using two layers of PET as the reference line of light transmittance, the PET film was peeled off from the obtained three-layer laminate (PET film/cured material/PET film), and the transmittance of the residual cured product at a wavelength of 440 nm was used for spectrophotometry. (Measured by Shimadzu Corporation (stock), product name "UV-2400PC").

Further, the value of the measured transmittance at 440 nm was evaluated by the following criteria.

A: The light transmittance at a wavelength of 440 nm is 98% or more, and the light transmittance is good.

F: The light transmittance at a wavelength of 440 nm is less than 98%, and the light transmittance is inferior.

(refractive index)

The resin composition obtained in each of the examples and the comparative examples was dropped on a PET (polyethylene terephthalate) film (manufactured by Toyobo Co., Ltd., product name "A4100", 86 mm × 56 mm × 100 μm). The film thickness of the resin composition after curing of the same PET film by a separator of 350 μm was 350 μm. Then, an ultraviolet ray irradiation device (product name "ELM-3000B-6N" manufactured by ORC Co., Ltd.) was used for one of the PET sheets, and ultraviolet rays of 2,000 mJ/cm ^{2 were} irradiated to cure the resin composition to produce a transparent sheet (cured material). ).

The PET film was peeled off from the obtained three-layer laminate (PET film/cured material/PET film), and the refractive index of the residual cured product at 25 ° C and a wavelength of 589 nm was measured by an ABBE refractometer (Atago). Name "DR-M2") Determination.

(Dielectric constant at a frequency of 1 MHz)

On the release PET film, a silicone circular frame having a diameter of 50 mm and a film thickness of 2 mm was placed, and the resin composition obtained in each of the examples and the comparative examples was filled therein, and the PET film was covered thereon, and an ultraviolet irradiation device was used. The product name "ELM-3000B-6N" manufactured by ORC Co., Ltd. was irradiated with ultraviolet rays of 1 J/cm ² to cure the resin composition to produce a transparent film (cured film). The dielectric constant at a frequency of 1 MHz of the cured film was measured using special electrodes "HP16451B" and "HP4275A" (product name, Precision LCR Meter manufactured by Hewlett-Packard Co., Ltd.) for dielectric material measurement.

(shading portion hardening width)

The resin composition obtained in each of the examples and the comparative examples was dropped on a glass substrate of 16 cm square, and another 16 cm square glass substrate was bonded to a 175 μm film to have a film thickness of 175 μm. Then, an ultraviolet ray irradiation apparatus (product name "ELM-3000B-6N" manufactured by ORC Co., Ltd.) was used to irradiate ultraviolet rays of 2,000 mJ/cm ² to cure the resin composition, thereby preparing a test piece (cured material). ). Further, at this time, a black ceramic having a light transmittance of 0 at a wavelength of 200 to 800 nm was formed on one side of the glass substrate irradiated with ultraviolet rays to form a light-shielding portion of 8 cm × 16 cm, and was provided on the surface of the resin composition side.

Thereafter, the glass of the test piece was peeled off, and the resin composition of the fully formed film portion of the light-shielding portion was measured with a vernier caliper, and this value was defined as the light-shielding portion hardening width. The larger the value, the more excellent the hardenability in the light shielding portion.

Table 1

Table 2

As is apparent from Table 1, the photocurable resin compositions of Examples 1 to 8 have an appropriate viscosity, good compatibility, and a light-shielding portion hardening width of 40 mm or more, and are excellent in hardenability in a light-shielding portion. Further, the cured product of the resin composition had good light transmittance, refractive index, and dielectric constant.

On the other hand, as is clear from Table 2, in the photocurable resin compositions of Comparative Examples 1 to 4 and 6 to 9, the curing of the light-shielding portion was not sufficiently performed. Further, as a result of the photocurable resin compositions of Comparative Examples 5 to 9, the compatibility was poor, and the resin group was The light transmittance of the cured product obtained by the product is also inferior.

[Industry Utilization]

The photocurable resin composition of the present invention is excellent in curability in a light-shielding portion, has an appropriate viscosity, and has good compatibility. Therefore, the photocurable resin composition of the present invention can be suitably used in a video display device, and has a filling material in a space portion of a gap between a protective panel and a video display element such as a light shielding portion on the outer periphery.

1A‧‧‧LCD display device

1‧‧‧Image display components

10‧‧‧LCD unit

20, 22‧‧‧ polarizing plate

32‧‧‧ resin layer

40‧‧‧Protection panel

41‧‧‧Lighting Department

50‧‧‧Backlight system

P‧‧‧Back side of the sunscreen

Q‧‧‧Transmission Department

Claims (14)

A photocurable resin composition comprising: (A) a compound having a structural unit derived from polybutadiene; (B) a compound represented by the following formula (1); (C) having the following formula a thiol compound represented by (II); and (D) a photopolymerization initiator; wherein, as the component (A), the component (A1) is contained, and the component (A1) has (meth)acryl oxime a compound having a structural unit derived from polybutadiene; (In the formula (1), R ¹ represents a hydrogen atom or a methyl group, R ² represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, and n represents an integer of 1 to 7) (R ³ and R ⁴ in the formula (II) each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, q represents an integer of 0 to 3, and * represents a bonding moiety). The photocurable resin composition according to claim 1, wherein the component (C) is a thiol compound represented by the following formula (2). (R ³ and R ⁴ in the formula (2) each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, p represents an integer of 1 to 6, q represents an integer of 0 to 3, and A represents a p-valent value. Organic base). The photocurable resin composition according to claim 1 or 2, wherein R ² in the above formula (1) is an alkyl group having 4 to 12 carbon atoms. The photocurable resin composition according to any one of claims 1 to 3, which is substantially free of an organic solvent and has a viscosity of 500 to 5000 mPa at 25 ° C. s. The photocurable resin composition according to any one of claims 1 to 4, wherein the content of the component (C) is 3 to 30% by mass based on the total amount of the components (A) to (C). . The photocurable resin composition according to any one of claims 1 to 5, wherein the content of the component (A1) is from 25 to 100% by mass based on the total amount of the component (A). The photocurable resin composition according to any one of claims 1 to 6, wherein the component (A) further contains a component (A2) which does not have (meth)acrylic acid. And a compound having a structural unit derived from polybutadiene. The photocurable resin composition according to claim 7, wherein the mass ratio of (A1) component to (A2) [(A1)/(A2)] is 25/75 to 95. /5. The photocurable resin composition according to any one of claims 2 to 8, wherein A in the above formula (2) is represented by the following formula (C-1) or (C-2) Base, or alkylene with a carbon number of 1 to 12, (In the formula (C-1) or (C-2), * represents a bonding moiety, and X ¹ to X ⁷ each independently represent a single bond or an alkylene group having 1 to 12 carbon atoms which may have a substituent). The photocurable resin composition according to any one of claims 1 to 9, wherein the content of the component (B) is 1 to 40% by mass based on the total of the components (A) to (C). . The photocurable resin composition according to any one of claims 1 to 10, wherein the content of the component (A) is 50 to 98% by mass based on the total of the components (A) to (C). . An image display device is a video display device having a laminated structure, the laminated structure comprising: an image display device having an image display portion; a protective panel having a light blocking portion along an outer periphery; and a resin layer Existing in the foregoing image display element and the foregoing protective panel The resin layer is a cured product of the photocurable resin composition according to any one of claims 1 to 11. An image display device is a video display device having a laminated structure, the laminated structure comprising: an image display device having an image display portion; a touch panel; and a protection panel having a light shielding portion along the outer periphery; A resin layer which is present between the touch panel and the protective panel, wherein the resin layer is a cured product of the photocurable resin composition according to any one of claims 1 to 11. A method for manufacturing an image display device, wherein an image display device or a touch panel having a video display portion is disposed opposite to a protective panel having a light shielding portion along an outer periphery, and then a photocurable resin composition is interposed. A photocurable resin composition according to any one of claims 1 to 11, wherein the photocurable resin composition is cured in a gap between the members and the photocurable resin composition is cured. The photocurable resin composition is cured by light irradiation from at least the protective panel side in the gap.