JP6679960B2 - Optical active energy ray-polymerizable adhesive and optical laminate - Google Patents

Description

  The present invention relates to an optical active energy ray-polymerizable adhesive and an optical laminate.

  In optical applications such as display devices such as displays, the active energy ray-polymerizable adhesive has a high polymerization rate and can be generally used without a solvent, so that it has excellent workability, and the energy required for polymerization is extremely low. It is widely used due to its excellent properties. As the active energy ray-polymerizable adhesive, a radical polymerizable active energy ray-polymerizable adhesive and a cationically polymerizable active energy ray-polymerizable adhesive are generally known.

  For display devices such as displays, there are usually various films such as an antireflection film for preventing reflection from an external light source and a protective film (protective film) for preventing scratches on the surface of the display device, depending on the application. Is used, and for example, in a member for liquid crystal cells that constitutes a liquid crystal display (LCD), a polarizing plate and a retardation film are laminated.

  A flat panel display (FPD) may be used not only as a display device but also as an input device by providing a touch panel function on its surface. A protective film, an antireflection film, an ITO vapor deposition resin film, and the like are also used for touch panels.

  Further, a backlight system in which a liquid crystal layer is illuminated from the back side to emit light is widely used in display devices, and an edge light type, a direct type backlight unit or the like is provided on the lower surface side of the liquid crystal layer. Such an edge light type backlight unit basically has a linear lamp as a light source, a rectangular plate-shaped light guide plate arranged so that an end portion is along the lamp, and a surface side of the light guide plate. And a prism sheet provided on the front surface side of the light diffusion sheet. Recently, as a light source, a light emitting diode (LED) excellent in color reproducibility and power saving has been used in place of a cold cathode tube (CCFL), so that the demand for heat resistance and dimensional stability is increasing. Is coming.

  By the way, display devices have come to be used in various environments as their applications have expanded. For example, a vehicle-mounted liquid crystal display device such as a car navigation system is exposed to a severe high temperature atmosphere in the summer, and thus an adhesive force at high temperature is required. Furthermore, in cold regions in winter, low-temperature adhesion is required.

  As an adhesive used for a display device, an adhesive containing a carboxyl group-containing vinyl polymer and a vinyl monomer (Patent Document 1) is disclosed.

  Patent Document 2 discloses an active energy ray adhesive containing an alicyclic epoxy resin, a polyol having a number average molecular weight of 400 or more, and an active energy ray sensitive catalyst.

JP, 2015-110763, A JP, 2007-224235, A

  However, the display device using the conventional active energy ray adhesive has an insufficient adhesive force in a wide temperature range from a high temperature to a low temperature such as an in-vehicle application, and particularly, an adhesive force at a low temperature is insufficient.

  An object of the present invention is to provide an optical active energy ray adhesive having excellent adhesive force in a wide temperature range from high temperature to low temperature.

The present inventors have completed the present invention as a result of intensive studies to solve the above problems.
That is, the present invention provides a (meth) acrylate monomer (A) having a heterocycle having a molecular weight of less than 500 (however, excluding acryloylmorpholine), and a (meth) acrylate monomer (B) having a hydroxyl group having a molecular weight of less than 500 (provided that , (Excluding (meth) acrylate monomer (A) having a heterocycle) and (meth) acrylate monomer (C) having a ring other than a heterocycle having a molecular weight of less than 500 (provided that a heterocycle having a molecular weight of less than 500 ( (Excluding a (meth) acrylate monomer (A) and a (meth) acrylate monomer having a hydroxyl group (B)), and the heterocycle is selected from the group consisting of sulfur, oxygen and nitrogen as atoms constituting the ring. The present invention relates to an optical active energy ray-polymerizable adhesive containing one or more heteroatoms.

In addition, the present invention further comprises a polyurethane-based oligomer (D1) having a (meth) acryloyl group, a polyester-based oligomer (D2) having a (meth) acryloyl group, and an epoxy oligomer (D3) having a (meth) acryloyl group. The above-mentioned optical active energy ray-polymerizable adhesive containing one or more oligomers selected from the group consisting of:
Regarding

In the present invention, the active energy ray-polymerizable adhesive for optics contains 5 to 70% by mass of a (meth) acrylate monomer (A) having a heterocycle, and a hydroxyl group-containing (meth) acrylate monomer (B) 20 to 80. The above-mentioned active energy ray-polymerizable adhesive for optics containing 5% to 50% by mass of (meth) acrylate monomer (C) having a ring structure other than heterocycle.
Regarding

  The present invention also relates to an optical laminate including a first base material, a resin layer that is a cured product of the above-mentioned optical active energy ray-polymerizable adhesive, and a second base material.

  The present invention has made it possible to provide an active energy ray-polymerizable adhesive for optics, which has excellent adhesive force in a wide temperature range from high temperature to low temperature.

Hereinafter, embodiments of the present invention will be described.
<Optical active energy ray-polymerizable adhesive>
The optical active energy ray-polymerizable adhesive of the present invention (hereinafter sometimes simply referred to as “adhesive”) is a (meth) acrylate monomer (A) having a heterocycle having a molecular weight of less than 500 (provided that acryloyl is used). Morpholine is excluded), (meth) acrylate monomer (B) having a hydroxyl group with a molecular weight of less than 500 (excluding (meth) acrylate monomer (A) having a heterocycle), and rings other than heterocycle having a molecular weight of less than 500. And a (meth) acrylate monomer (C) having a molecular weight of less than 500 (excluding the (meth) acrylate monomer (A) having a heterocycle having a molecular weight of less than 500 and the (meth) acrylate (B) having a hydroxyl group). Is two or more hethenes selected from the group consisting of sulfur, oxygen and nitrogen as ring-constituting atoms. Characterized in that it comprises an atom.

  Here, the term “active energy ray” means an energy ray in a broad sense, which includes ultraviolet rays, visible rays, infrared rays, electron beams (EB), and radiation, which can provide energy necessary for activation to cause a chemical reaction. means. The active energy ray-polymerizable adhesive of the present invention undergoes a polymerization reaction upon irradiation with the active energy ray to form a cured product such as a resin layer.

  In addition, in the present specification, when it is described as “(meth) acryloyl”, “(meth) acrylic acid”, “(meth) acrylate”, “(meth) acryloyloxy”, and “(meth) allyl”, Unless otherwise specified, “acryloyl and / or methacryloyl”, “acrylic acid and / or methacrylic acid”, “acrylate and / or methacrylate”, “acryloyloxy and / or methacryloyloxy”, and “allyl and / or respectively” Or methallyl ”.

<(Meth) acrylate monomer (A) having a heterocycle having a molecular weight of less than 500>
A (meth) acrylate monomer (A) having a heterocycle having a molecular weight of less than 500 (hereinafter, also referred to as compound (A)) is a group consisting of sulfur, oxygen and nitrogen as atoms (ring members) constituting the ring. A compound having a (meth) acryloyl group and a heterocycle containing two or more heteroatoms selected from the above.
By containing the compound (A) in the adhesive, a hydrogen bond is formed between the hetero atom of the heterocycle and the functional group such as a hydroxyl group on the surface of the base material, and the adhesive strength at room temperature and low temperature is improved. Further, the annular structure improves the cohesive force at high temperature and improves the adhesive force at high temperature.

The heterocycle containing two or more heteroatoms selected from the group consisting of sulfur, oxygen and nitrogen as a ring member atom, a heterocycle having two or more sulfur atoms such as a dithiolane ring and a dithiol ring, a carbonate ring, Heterocycle having two or more oxygen atoms such as dioxolane ring, dioxane ring, isocyanuric ring, imidazole ring, pyrazole ring, pyrazine ring, pyrimidine ring, heterocycle having two or more nitrogen atoms such as piperazine ring, oxazole ring , Isoxazole ring, oxazine ring, oxadiazole ring, oxadiazine ring, etc. heterocyclic ring having oxygen atom and nitrogen atom, thiazole ring, benzothiazole ring, isothiazole ring, thiazine ring, thiadiazole ring, thiadiazine ring, dithiazine ring, etc. And a heterocycle having a sulfur atom and a nitrogen atom.
Of these heterocycles, a heterocycle having two or more oxygen atoms as ring member atoms is preferable, and a heterocycle having two oxygen atoms as ring member atoms is preferable in that it is excellent in a wide temperature range from high temperature to low temperature. Is preferred. Further, a monocyclic heterocycle is preferable to the condensed heterocycle, and an aliphatic heterocycle is preferable to the aromatic heterocycle. More specifically, a dioxolane ring and a dioxane ring are particularly preferable.

  Although the reason is unknown, it is not preferable to include acryloylmorpholine in the optical active energy ray-polymerizable adhesive, because the viscosity of the adhesive decreases when it is stored for a long time.

  The number of (meth) acryloyl groups in the compound (A) is preferably 1 to 6 from the viewpoint of improving the adhesive force in a wide temperature range from high temperature to low temperature, and particularly preferably 1.

  Specific examples of the compound (A) include (2-methyl-2-ethyl-1,3dioxolan-4-yl) methyl (meth) acrylate and 5-ethyl-1,3-dioxane-5 (meth) acrylate. -Ylmethyl, (2-oxo-1,3-dioxolan-4-yl) methyl (meth) acrylate, 1,3-dioxan-2-one-5-yl (meth) acrylate, 1- (meth) acryloyl- 4-Methylpiperazine, (meth) acrylic acid 11- [1 ', 3', 3'-trimethylspiro [3H-naphtho [2,1-b] [1,4] oxazine-3,2 '(3'H )-[1H] indole] -5′-yloxy] undecyl, 2,5-bis ((meth) acryloyloxyethylthiomethyl) -1,4-dithiane and the like, 2-methyl-2-ethyl- 1,3 dioxolane 4-yl) methyl (meth) acrylate and 5-ethyl-1,3-dioxan-5-ylmethyl (meth) acrylate are preferable because they are excellent in a wide temperature range from high temperature to low temperature.

<(Meth) acrylate monomer (B) having a hydroxyl group having a molecular weight of less than 500>
The (meth) acrylate (B) having a hydroxyl group having a molecular weight of less than 500 (hereinafter, also referred to as compound (B)) is not particularly limited as long as it is a (meth) acrylate having a hydroxyl group.
By containing the compound (B) in the adhesive, a hydrogen bond is formed with the hydroxyl group of the base material, and the adhesive strength at room temperature and low temperature is improved.

As the compound (B), for example, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, ( 6-hydroxyhexyl (meth) acrylic acid, 8-hydroxyoctyl (meth) acrylic acid, cyclohexanedimethanol mono (meth) acrylic acid ester, 12-hydroxylauryl (meth) acrylic acid, ethyl (meth) acrylate-α- ( Monofunctional (meth) acrylic acid glycerol such as hydroxymethyl);
Fatty acid ester-based (meth) acrylic acid ester such as glycidyl lauric acid ester (meth) acrylic acid;

Cyclohexanedimethanol mono (meth) acrylate, cyclohexanediethanol mono (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, 2-a (meth) acryloyloxyethyl-2-hydroxyethylphthalic acid, etc. (Meth) acrylic acid ester;
A (meth) acrylic acid ester having a hydroxyl group added to the molecular end by ring-opening addition of ε-caprolactone to the above-mentioned (meth) acrylate having a hydroxyl group;
Aliphatic (meth) acrylic acid esters and the like of alkylene oxide addition (meth) acrylic acid esters and the like in which alkylene oxides such as ethylene oxide, propylene oxide and butylene oxide are repeatedly added to the above-mentioned (meth) acrylate having a hydroxyl group; To be

  The compound (B) has excellent adhesiveness at low temperature, and is therefore 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, and (meth) acrylic. 4-hydroxybutyl acid is preferred, and 4-hydroxybutyl (meth) acrylate is particularly preferred.

<(Meth) acrylate monomer (C) having a ring structure other than a heterocycle having a weight average molecular weight of less than 500>
A (meth) acrylate monomer (C) having a ring structure other than a heterocycle having a molecular weight of less than 500 (hereinafter, also referred to as compound (C)) means a hydrocarbon ring other than the heterocycle (an aromatic hydrocarbon ring or an aliphatic ring). (Meth) acrylate compound containing a (hydrocarbon ring). The compound (C) is preferably a (meth) acrylate compound containing no hydrocarbon ring but a hydrocarbon ring (aromatic hydrocarbon ring or aliphatic hydrocarbon ring). By containing the compound (C), an optical active energy ray-polymerizable adhesive having excellent adhesive strength at high temperature can be obtained.

Examples of the compound (C) include benzyl (meth) acrylate, phenoxy (meth) acrylate, ethylene oxide-modified phenoxy (meth) acrylate, bisphenol A di (meth) acrylate, alkylene oxide-modified bisphenol A di (meth) acrylate, and bisphenol. F has an aromatic hydrocarbon ring such as di (meth) acrylate, alkylene oxide-modified bisphenol F di (meth) acrylate, 2- (meth) acryloyloxyethylphthalic acid, neopentyl glycol-acrylic acid-benzoic acid ester (meth ) Acrylate compounds;
(Meth) acrylate compound having one or more aliphatic hydrocarbon rings such as hydrogenated bisphenol A di (meth) acrylate, 2- (meth) acryloyloxyethyl hexahydrophthalic acid, and cyclohexyl methacrylate;
3,3-dicyclopropyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dimethyloldicyclopentanedi (meth) acrylate, Tricyclodecane dimethanol di (meth) acrylate, isobornyl (meth) acrylate, 3-hydroxy-1-adamantyl (meth) acrylate, 2-methyl-2-adamantyl (meth) acrylate, 2-ethyl-2-adamantyl (meth ) Acrylate, 2-propyl-2-adamantyl (meth) acrylate, 3,5-dihydroxy-1-adamantyl (meth) acrylate, 1,3-adamantyldiol di (meth) acrylate, 1,3,5-adamantyl tri ( (Meta) Acrylate, 3-hydroxy-1,5 having Adamanchiruji (meth) aliphatic hydrocarbon condensed rings such as acrylates (meth) acrylate compounds, and the like.

  As the compound (C), a (meth) acrylate compound having a condensed aliphatic hydrocarbon ring is preferable in terms of excellent adhesiveness at high temperature. Specifically, dicyclopentenyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, dicyclopentanyl (meth) acrylate, tricyclodecane dimethanol di (meth) acrylate, and isobornyl (meth) acrylate are preferable. , Tricyclodecane dimethanol di (meth) acrylate and isobornyl (meth) acrylate are particularly preferable.

  The contents of the compounds (A), (B), and (C) in the active energy ray-polymerizable adhesive for optics are as follows: compound (A) 5 to 70% by mass, compound (B) 20 to 80% by mass, compound ( C) is preferably 5 to 50% by mass, more preferably compound (A) 10 to 70% by mass, compound (B) 30 to 70% by mass, and compound (C) 5 to 40% by mass. The total amount of the compounds (A), (B) and (C) in the optical active energy ray-polymerizable adhesive is preferably 70% by mass or more.

The active energy ray-polymerizable adhesive for optics of the present invention further comprises a (meth) acryloyl group-containing polyurethane oligomer (D1) (hereinafter, also referred to as compound (D1)) and a (meth) acryloyl group-containing polyester oligomer. At least one oligomer selected from the group consisting of (D2) (hereinafter, also referred to as compound (D2)) and an epoxy oligomer (D3) having a (meth) acryloyl group (hereinafter, also referred to as compound (D3)). It is preferable in that the adhesive strength at room temperature is improved.
The weight average molecular weight of the compounds (D1), (D2) and (D3) is preferably 500 to 100,000. The weight average molecular weight in the present specification is a value measured by gel permeation chromatography (GPC) using polystyrene having a known weight average molecular weight as a standard substance.

<Polyurethane oligomer having (meth) acryloyl group (D1)>
The polyurethane-based oligomer (D1) having a (meth) acryloyl group (compound (D1)) is a compound having a urethane bond and a (meth) acryloyl group in the molecule. For example, it can be obtained by reacting a compound having an isocyanate group at the terminal obtained by reacting a compound having one or more isocyanate groups with a compound having a hydroxyl group with a (meth) acryloyl group having a hydroxyl group.

  Examples of the compound having at least one isocyanate group include 4,4′-diphenylmethane diisocyanate, 2,4-tolylene diisocyanate, aromatic isocyanate such as 1,4-phenylene bismethylene diisocyanate, and 3-isocyanate methyl- Aliphatic isocyanates such as 3,5,5-trimethylcyclohexyl isocyanate and hexamethylene diisocyanate are listed.

  Specific examples of the compound (D1) include aromatic polyurethane-based oligomers such as EBECRYL210, EBECRYL220 (above, produced by Daicel Ornex), CN9782, CN9783 (above, produced by SARTOMER), Shiko 3000B, Shiko 3700B (above, Japan). Synthetic Chemical Industry Co., Ltd.), EBECRYL230, EBECRYL270, EBECRYL8402, EBECRYL8701 (above, manufactured by Daicel Ornex) and the like.

<Polyester oligomer (D2) having (meth) acryloyl group>
The polyester oligomer (D2) having a (meth) acryloyl group (compound (D2)) is a compound having an ester bond and a (meth) acryloyl group in the molecule. For example, a polyester obtained by polycondensing a polybasic acid and a polyhydric alcohol in the main chain skeleton has a hydroxyl group at the terminal or the polyester chain and one or more carboxyl groups in the molecule such as (meth) acrylic acid (meta). ) It can be obtained by an esterification reaction with an acrylate.

  Examples of the polybasic acid include oxalic acid, malonic acid, succinic acid, adipic acid, sebacic acid, azelaic acid, suberic acid, maleic acid, fumaric acid, itaconic acid, succinic anhydride, and maleic anhydride. Examples thereof include alicyclic compounds such as basic acid, dimer acid and cyclohexanedicarboxylic acid, and aromatic compounds such as isophthalic acid, terephthalic acid and biphenyldicarboxylic acid.

  Examples of polyhydric alcohols include relatively low molecular weight polyols having a number average molecular weight (Mn) of 50 to 500, and relatively high molecular weight polyols having a number average molecular weight (Mn) of 500 to 30,000.

  Specific examples of the compound (D2) include aromatic polyester oligomers such as CN296, CN2203, CN2259, CN2261 (above, manufactured by SARTOMER), and aliphatic polyesters such as CN294, CN2270, CN2271 (above, manufactured by SARTOMER). Examples include system oligomers.

<Epoxy oligomer (D3) having (meth) acryloyl group>
The epoxy-based oligomer (D3) (compound (D3)) having a (meth) acryloyl group is a partial structure obtained by reacting an epoxy group of an epoxy compound with a compound having a carboxyl group and / or a hydroxyl group, and (meth) It is a compound having an acryloyl group.

  Examples of the epoxy compound include aromatic epoxy compounds such as bisphenol type epoxy, aliphatic epoxy compounds such as diglycidyl ether of diol having 2 to 20 carbon atoms, and alicyclic epoxy compounds.

  Specific examples of the compound (D3) include aromatic epoxy oligomers such as CN104, CN110 (above, manufactured by SARTOMER), EBECRYL600, EBECRYL3701 (above, manufactured by Daicel Ornex), CN111, CN113 (above, manufactured by SARTOMER). ) And EBECRYL860 (manufactured by Daicel Ornex) and the like.

  The content of the compounds (D1), (D2) and (D3) in the active energy ray-polymerizable adhesive for optics is such that the sum of the compounds (D1), (D2) and (D3) is 1 to 30% by mass. It is preferably present, and more preferably 3 to 20% by mass.

  The active energy ray-polymerizable adhesive for optics of the present invention includes other (meth) acrylate compounds (E) other than the compounds (A), (B), (C), (D1), (D2) and (D3). (Hereinafter, also referred to as compound (E)) or cationically polymerizable compound (F) (hereinafter, also referred to as compound (F)) may be included.

  By containing the compound (E), the viscosity of the active energy ray polymerizable adhesive for optics can be lowered to improve the coatability, and the durability such as wet heat resistance can be further improved.

Examples of the compound (E) include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, n-hexyl (meth) acrylate, lauryl (meth) acrylate, and (meth). (Meth) acrylic acid alkyl ester such as stearyl acrylate;
(Meth) allyl (meth) acrylate, 1-butenyl (meth) acrylate, 3,7-dimethyloct-6-en-1-yl (meth) acrylate, 2- (2-vinyloxyethoxy) acrylate (Meth) acrylic acid ester containing ethyl and other unsaturated groups such as vinyl (meth) acrylate;

(Meth) acrylic acid perfluoroalkyl esters such as perfluoromethyl (meth) acrylate, 2-perfluoroethylethyl (meth) acrylate, and 2-perfluorohexadecylethyl (meth) acrylate;
(Methoxycarbonyl) methyl (meth) acrylate, 2- (ethoxycarbonyloxy) hexyl (meth) acrylate, 2- (propoxycarbonyloxy) ethyl (meth) acrylate, and 2- (octyloxy) (meth) acrylate An aliphatic (meth) acrylic acid ester having one carbonyl group such as carbonyloxy) butyl;
2-Oxobutanoylethyl (meth) acrylate, 3-oxobutanoylpropyl (meth) acrylate, 2,3-di (oxobutanoyl) butyl (meth) acrylate, 2,3- (meth) acrylate Aliphatic (meth) acrylic acid ester having two carbonyl groups such as di (oxobutanoyl) hexyl;

2-Methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, 2-propoxyethyl (meth) acrylate, 3-propoxyethyl (meth) acrylate, 2-butoxyethyl (meth) acrylate, Alkoxy group-containing (meth) acrylic acid ester such as 3-butoxyethyl (meth) acrylate and 4-butoxyethyl (meth) acrylate;
Alkylene oxide-containing (meth) acrylic acid derivative such as alkylene oxide adduct of (meth) acrylic acid;

Ethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, 2,2-dimethylpropyl diol di (meth) acrylate, hydroxy di (meth) acrylate Pivalyl hydroxypivalate, di (meth) acrylic acid 2,5-hexanediol, di (meth) acrylic acid 1,2-octanediol, di (meth) acrylic acid 2,2-diethyl-1,3-propanediol , And a bifunctional (meth) acrylic acid ester such as di (meth) acrylic acid 2,5-dimethyl-2,5-hexanediol;
1,2,3-propanetriol tri (meth) acrylate, trimethylolhexane tri (meth) acrylate, trimethyloloctane tri (meth) acrylate, and 1,1,1-trishydroxy tri (meth) acrylate Trifunctional (meth) acrylic acid ester such as methylethane;

Pentaerythritol tetra (meth) acrylate, 2,2-bis (hydroxymethyl) 1,3-propanediol tetra (meth) acrylate, and di2,2-bis (hydroxymethyl) 1,2 hepta (meth) acrylate Polyfunctional (meth) acrylic acid ester such as 3-propanediol polyalkylene oxide;
A (meth) acrylate compound having a cationically polymerizable functional group such as glycidyl (meth) acrylate and 3,4-epoxycyclohexylmethyl (meth) acrylate;
Examples thereof include (meth) acrylate compounds having a heterocycle containing one hetero atom such as tetrahydrofurfuryl (meth) acrylate.

<Cationically polymerizable compound (F)>
As the compound (F), a compound having an epoxy group which is a three-membered ring ether, a compound having an oxetanyl group which is a four-membered ring ether, a vinyl ether compound, a cyclic ester compound, a cyclic formal compound, a cyclic carbonate compound and a fluorine-containing compound. Cyclic compounds and the like are preferable. Of the above compounds, none of the compounds having a ring has a (meth) acryloyl group and is therefore different from the compounds (A), (B) and (C).
By including the compound (F), the curing shrinkage of the adhesive is reduced, and the adhesive strength at room temperature is improved.

  As the compound having an epoxy group (epoxy compound), an aromatic epoxy compound, an aliphatic epoxy compound, an alicyclic epoxy compound and the like are preferable.

  Examples of the aromatic epoxy compound include bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, bisphenol S diglycidyl ether, bisphenol A propylene oxide adduct diglycidyl ether, and phenol novolac. Epoxy, cresol novolac epoxy, biphenyl type epoxy, resorcin diglycidyl ether, phenyl glycidyl ether, phenol ethylene oxide glycidyl ether, t-butylphenyl glycidyl ether and the like can be mentioned.

  As the aliphatic epoxy compound, aliphatic monoalcohols, aliphatic polyalcohols, and glycidyl ethers of alkylene oxide adducts thereof are preferable. Examples of the aliphatic epoxy compound include allyl glycidyl ether, 2-ethylhexyl glycidyl ether, 1,4-butanediol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, Triglycidyl ether of glycerin, triglycidyl ether of trimethylolpropane, diglycidyl ether of polyethylene glycol, diglycidyl ether of polypropylene glycol, ethylene glycol, polypropylene glycol, and 1 or 2 for aliphatic polyhydric alcohol such as glycerin. Polyglycidyl ether of polyether polyol obtained by adding at least one alkylene oxide (ethylene oxide or polypropylene oxide) And the like.

  Examples of the alicyclic epoxy compound include 1,2-epoxy-4-vinylcyclohexane, 1,2: 8,9 diepoxy limonene, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, 2 -(3,4-epoxycyclohexyl-5,5-spiro-3,4-epoxy) cyclohexane-meta-dioxane, bis (3,4-epoxycyclohexylmethyl) adipate, bis (3,4-epoxy-6) -Methylcyclohexylmethyl) adipate and the like.

  Usually, the epoxy equivalent of the epoxy compound is preferably about 30 to 3000 g / eq, more preferably 50 to 1500 g / eq. When the epoxy equivalent is 30 g / eq or more, the flexibility of the sheet after curing is excellent and the adhesive force is further improved. When it is 3000 g / eq or less, the curability is excellent and the adhesive strength is improved.

  Examples of the compound having an oxetanyl group include 3-ethyl-3-hydroxymethyloxetane, 1,4-bis [(3-ethyl-3-oxetanyl) methoxymethyl] benzene, di (1-ethyl-3-oxetanyl) Methyl ether, 3-ethyl-3- (phenoxymethyl) oxetane, 3-ethyl-3- (2-ethylhexyloxymethyl) oxetane, phenol-novolak oxetane, 3-ethyl-{(3-triethoxysilylpropoxy) Methyl} oxetane and the like.

Examples of the vinyl ether compound include those having 5 to 20 carbon atoms such as n-amyl vinyl ether, i-amyl vinyl ether, n-hexyl vinyl ether, n-octyl vinyl ether, 2-ethylhexyl vinyl ether, n-dodecyl vinyl ether, stearyl vinyl ether and oleyl vinyl ether. Vinyl ethers of alkyl alcohols and alkenyl alcohols;
Vinyl alcohol of monoalcohol having an aliphatic ring or an aromatic ring such as cyclohexyl vinyl ether, 2-methylcyclohexyl vinyl ether, cyclohexyl methyl vinyl ether, benzyl vinyl ether;
Glycerol monovinyl ether, 1,4-butanediol monovinyl ether, 1,4-butanediol divinyl ether, 1,6-hexanediol divinyl ether, neopentyl glycol divinyl ether, pentaerythritol divinyl ether, pentaerythritol Tetravinyl ether, trimethylolpropane divinyl ether, trimethylolpropane trivinyl ether, 1,4-dihydroxycyclohexane monovinyl ether, 1,4-dihydroxycyclohexane divinyl ether, 1,4-dihydroxymethylcyclohexane monovinyl ether, 1,4-dihydroxy Monovinyl ethers and polyvinyl ethers of polyhydric alcohols such as methylcyclohexanedivinyl ether;
Polyalkylene glycol monodivinyl ether and divinyl ether such as triethylene glycol divinyl ether and diethylene glycol monobutyl monovinyl ether;
Other vinyl ethers such as glycidyl vinyl ether and ethylene glycol vinyl ether methacrylate may be mentioned.

  Examples of the cyclic ester compound include lactone and the like. Examples of the cyclic carbonate compound include ethylene carbonate and propylene carbonate. Examples of the cyclic formal compound include dioxolane, dioxane, trioxane and the like. The compound (F) can be used alone or in combination of two or more kinds.

  The compound (F) is preferably a compound having an epoxy group and a compound having an oxetanyl group. Among compounds having an epoxy group and compounds having an oxetanyl group, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, bis (3,4-epoxycyclohexylmethyl) adipate, bisphenol A di Glycidyl ether, bisphenol F diglycidyl ether, and 1,6-hexanediol diglycidyl ether are preferable because they have particularly excellent reactivity.

<Active energy ray polymerization initiator (G)>
The optical active energy ray-polymerizable adhesive may contain an active energy ray polymerization initiator (G) (hereinafter, also referred to as compound (G)). Examples of the compound (G) include an active energy ray radical polymerization initiator (g1), an active energy ray cationic polymerization initiator (g2), and an active energy ray anionic polymerization initiator (g3).
As the active energy ray radical polymerization initiator (g1), a known active energy ray radical polymerization initiator can be used. Commercial products include, for example, Irgacure-184, 907, 651, 1700, 1800, 819, 369, 261, DAROCUR-TPO (above, manufactured by BASF), Darocur-1173 (manufactured by Merck), Esacure-KIP150, Examples thereof include TZT (manufactured by Nippon Siber Hegna), Kayacure BMS, Kayacure DMBI, (all manufactured by Nippon Kayaku Co., Ltd.) and the like.

  As the active energy ray cationic polymerization initiator (g2), a known active energy ray cationic polymerization initiator can be used. Commercially available products include, for example, UVACURE1590 (manufactured by Daicel Cytec), sulfonium salts such as CPI-110P (manufactured by San-Apro), IRGACURE250 (manufactured by BASF), WPI-113 (manufactured by Wako Pure Chemical Industries, Ltd.), Rp. -2074 (made by Rhodia Japan) etc. are mentioned.

  As the active energy ray anionic polymerization initiator (g3), a known active energy ray anionic polymerization initiator can be used. Commercial products include, for example, WPBG-165, WPBG-018, WPBG-172, WPBG-140, WPBG-166, WPBG-027, WPBG-082, WPBG-167, WPBG-168, WPBG-266 (above, Wako Pure Chemical Industries, Ltd.) and the like.

  The compound (G) is preferably added in an amount of 0.1 to 10% by mass in 100% by mass of the active energy ray polymerizable adhesive for optics, and more preferably 0.5 to 5% by mass.

  The optical active energy ray-polymerizable adhesive of the present invention further comprises a photosensitizer, an amine-based catalyst, a phosphorus-based catalyst, a filler, an antistatic agent, an antioxidant, an antioxidant, a tackifier, if necessary. , An anti-blocking agent, an antifoaming agent, a plasticizer, a silane coupling agent, a titanium coupling agent and the like.

  The optical active energy ray-polymerizable adhesive of the present invention preferably contains substantially no organic solvent, and preferably contains no organic solvent at all. However, since the compound (G) is often hardly soluble in the polymerizable component, a small amount of an organic solvent may be included in order to dissolve the compound (G). The content of the organic solvent in the adhesive is preferably 5% by mass or less.

  The optical active energy ray-polymerizable adhesive of the present invention preferably has a viscosity at 25 ° C. of 1 to 2000 mPa · s from the viewpoint of controlling the smoothness of the coating film and the dimensional stability of the cured resin. , 10 to 1500 mPa · s, more preferably 20 to 1000 mPa · s.

  When the optical active energy ray-polymerizable adhesive is used as an adhesive layer of an optical laminate (hereinafter, may be simply referred to as “laminate”), the thickness of the adhesive layer is 0.1 to 6 μm. Is preferable, and 0.1-3 micrometers is more preferable. When the thickness of the adhesive layer is within the above range, the adhesive strength is further improved.

  A known coating device can be used for coating the adhesive with the base material. For example, wire bar, applicator, brush, sprayer, roller, gravure coater, die coater, micro gravure coater, lip coater, comma coater, Carter coater, knife coater, river coater, spin coater and the like can be mentioned.

  The active energy ray used for curing the adhesive is preferably light including ultraviolet rays, and the wavelength in that case is preferably 150 to 550 nm. Examples of the light source of active energy rays include low-pressure mercury lamps, medium-pressure mercury lamps, high-pressure mercury lamps, ultra-high pressure mercury lamps, chemical lamps, black light lamps, microwave-excited mercury lamps, LED lamps, xenon lamps, and metal halide lamps. .

The irradiation intensity of the active energy ray is preferably 10 to 500 mW / cm ² . Integrated irradiation dose, expressed as the product of the irradiation intensity and the irradiation time is preferably ^{10~5000mJ / cm 2, 30~4000mJ / cm} 2 is more preferable.

  The optical laminate of the present invention comprises a resin layer formed from an optical active energy ray-polymerizable adhesive, an adhesive layer, and a substrate.

  The polymerization reaction of the adhesive proceeds by irradiating with active energy rays during coating of the adhesive or when laminating, and further after laminating, but after laminating the base material, irradiating with active energy rays. It is preferable to proceed the polymerization reaction. At that time, in order to proceed the polymerization reaction by irradiation with active energy rays, at least one of the first base material and the second base material is preferably composed of a material that easily transmits active energy rays, Specifically, a transparent film, a plastic lens, a transparent glass plate and the like are preferable. For example, if a transparent film or a transparent glass plate is used as the first base material, a base material such as wood, a metal plate, a plastic plate, or a processed paper product that is difficult for active energy rays to pass therethrough is used as the second base material. You may use it.

  In the laminate of the present invention, it is preferable to use a film-shaped substrate as the substrate. Examples of the film-shaped substrate include cellophane, various plastic films, paper and the like. Above all, it is preferable to use various transparent plastic films. Further, the film-shaped substrate may have a single layer or a multi-layered structure in which a plurality of substrates are laminated as long as the film is transparent.

  Hereinafter, more specific embodiments of the optical layered body of the present invention will be described by taking a case where a transparent film is used as a substrate as an example.

  The laminate of the present invention is a sheet-like product obtained by laminating a plurality of transparent films such as transparent film / adhesive layer / transparent film or transparent film / adhesive layer / transparent film / adhesive layer / transparent film. It is a multilayer film. Further, it is also preferable that the sheet-shaped multilayer film is bonded to another optical member such as glass or an optical sheet. The laminated body can be obtained by curing the adhesive layer by irradiating the active energy ray-polymerizable adhesive for optics with an active energy ray from one side or both sides of the film to polymerize and cure the adhesive.

Examples of transparent films include polyvinyl alcohol films, polytriacetyl cellulose films, polypropylene-based films such as polypropylene, polyethylene, polycycloolefin, and ethylene-vinyl acetate copolymers; polyester-based films such as polyethylene terephthalate and polybutylene terephthalate. A polycarbonate film, a polynorbornene film, a polyarylate film, a polyacrylic film, a polyphenylene sulfide film, a polystyrene film, a polyvinyl film, a polyamide film, a polyimide film, and a polyoxirane film. .
When a transparent film is used as the substrate, the laminate of the present invention can be suitably used for optical applications.

  The thickness of the transparent film can be appropriately determined, but in general, 1 to 500 μm is preferable, 1 to 300 μm is more preferable, and 5 to 200 μm, from the viewpoint of film strength, workability, and thin layer property. More preferable. When used for optical purposes, the thickness of the transparent film is preferably 5 to 150 μm.

  As an example of the embodiment of the optical layered body of the present invention, an optical element layered body, it is preferable to use an optical film mainly used for optical applications as a transparent film.

  Examples of the optical film include a hard coat film, an antistatic coat film, an antiglare coat film, a polarizing film, a retardation film, an elliptically polarizing film, an antireflection film, a light diffusing film, a brightness improving film and a prism film (prism sheet). -Also referred to as a sheet), a decorative film (including a touch panel filling sheet), a light guide film (also referred to as a light guide plate), and the like.

  The active energy ray-polymerizable adhesive for optics of the present invention can be used to form a laminate of a liquid crystal display device, a PDP module, a touch panel module, an organic EL module or the like.

  Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto. In addition, "part" is "mass%" and "%" represents "mass%."

<Weight average molecular weight>
The weight average molecular weight is GPC (gel permeation chromatography) “SHODEX GPC System-21” manufactured by Showa Denko KK as a measuring device, using two Shodex GPC LF-604 manufactured by Showa Denko KK as a column, and tetrahydrofuran (DE) as a developing solvent. THF), a flow rate of 0.6 ml / min, and a column temperature of 40 ° C. The weight average molecular weight was determined by a calibration curve prepared using polystyrene having a known weight average molecular weight as a standard substance and having a monodisperse molecular weight.

[Example 1]
<Example of production of active energy ray-polymerizable adhesive>
(2-Methyl-2-ethyl-1,3-dioxolan-4-yl) methyl acrylate as a compound (A) (trade name: MEDOL-10, manufactured by Osaka Organic Chemical Industry Co., Ltd., molecular weight: 208) in a glass bottle with a capacity of 300 mL protected from light. ) 40 parts, 40 parts of 4-hydroxybutyl acrylate as the compound (B), 18 parts of dicyclopentenyl acrylate as the compound (C) (trade name FANCLyl 511AS manufactured by Hitachi Chemical Co., Ltd., molecular weight 204), Irgacure 184 (light manufactured by BASF) 2 parts of radical polymerization initiator) was added, and the mixture was sufficiently stirred and defoamed to obtain an active energy ray-polymerizable adhesive. The viscosity (initial viscosity) measured under the following conditions immediately after the production of the adhesive was 8 mPa · s.

<Viscosity over time>
The obtained active energy ray-polymerizable adhesive was stored at 40 ° C. for one month, and then the viscosity with time was measured under the following conditions. In addition, the viscosity change rate calculated by the formula 1 is within the range of ± 20%, which is the usable adhesive.
<Formula 1>
Viscosity change rate (%) = ((temporal viscosity-initial viscosity) / initial viscosity) × 100

<Viscosity measurement conditions>
Using an E-type viscometer (TV-22 manufactured by Toki Sangyo Co., Ltd.), 1.2 mL of the active energy ray-polymerizable adhesive was used as a measurement sample, and the conditions were 23 ° C., rotation speed 0.5 to 100 rpm, and rotation for 1 minute. The viscosity was measured at.

<Example of manufacturing laminated body>
As a transparent film, an ultraviolet absorber-containing polytriacetylcellulose film manufactured by Fuji Film Co., Ltd .: trade name “Fujitac: 80 μm” (thickness 80 μm), and a polynorbornene-based film manufactured by Nippon Zeon Co., Ltd. that does not contain an ultraviolet absorber. (Thickness 100 μm) was used. Corona treatment was performed on one surface of each of the two transparent films at a discharge amount of 300 W · min / m ² . Within 1 hour after that, the active energy ray-polymerizable adhesive was applied to the corona-treated surface of the ultraviolet absorber-containing polytriacetylcellulose-based film using a wire bar coater to have a thickness of 4 μm. So that it was applied. Further, a polynorbornene-based film containing no ultraviolet absorber was stacked, and the four sides were fixed to the tin plate with cellophane tape so that the polytriacetylcellulose-based film containing the ultraviolet absorber was in contact with the tin plate.

An active energy ray irradiation device (Toshiba high-pressure mercury lamp) was used to irradiate ultraviolet rays with a maximum illuminance of 500 mW / cm ² and an integrated light amount of 1000 mJ / cm ² from the polynorbornene-based film side containing no UV absorber manufactured by Zeon Corporation. , A laminate was created.

  The room temperature adhesive strength, the high temperature adhesive strength, and the low temperature adhesive strength of the obtained laminate were determined according to the following methods, and the results are shown in Table 1.

《Adhesion at room temperature》
The adhesive force was measured according to Japanese Industrial Standard (JIS) K6854-4 Adhesive-Peeling Adhesive Strength Test Method-Part 4: Floating Roller Method. That is, the obtained laminated body was cut into a size of 25 mm × 150 mm using a cutter to obtain a measurement sample. A double-sided adhesive tape (DF8712S manufactured by Toyochem Co., Ltd.) was attached to the surface of the sample polynorbornene-based film containing no ultraviolet absorber, and fixed on a metal plate using a laminator. The laminate for measurement is provided with a peeling maker in advance between the transparent films, and the laminate for measurement is subjected to the conditions of 23 ° C. and 50% relative humidity at a speed of 300 mm / min and 90 °. The ultraviolet absorber-containing polytriacetylcellulose-based film was peeled off at the angle of and the adhesive strength was measured. This adhesive strength was evaluated on a 4-point scale. A rating of ⊚, ◯, or Δ is a level that poses no problem in practical use.
⊚: Not peelable or substrate destroyed (extremely good)
◯: Peeling force is 2.0 (N / 25 mm) or more (good)
Δ: Peeling force is 1.0 (N / 25 mm) or more and less than 2.0 (N / 25 mm) (usable)
X: Peeling force is less than 1.0 (N / 25 mm) (cannot be used)

《High temperature adhesion》
In the above-mentioned room temperature adhesive strength evaluation method, the adhesive strength was measured in the same manner as the room temperature adhesive strength except that the temperature was changed from 23 ° C to 60 ° C. This adhesive strength was evaluated on a 4-point scale. A rating of ⊚, ◯, or Δ is a level that poses no problem in practical use.
⊚: Peeling force is 1.5 (N / 25 mm) or more (extremely good)
◯: Peeling force is 1.0 (N / 25 mm) or more and less than 1.5 (N / 25 mm) (good)
Δ: Peeling force is 0.5 (N / 25 mm) or more and less than 1.0 (N / 25 mm) (usable)
X: Peeling force is less than 0.5 (N / 25 mm) (cannot be used)

《Low temperature adhesion》
In the above-described room temperature adhesive strength evaluation method, the adhesive strength was measured in the same manner as the room temperature adhesive strength except that the temperature was changed from 23 ° C to 0 ° C. This adhesive strength was evaluated on a 4-point scale. A rating of ⊚, ◯, or Δ is a level that poses no problem in practical use.
⊚: Not peelable or substrate destroyed (extremely good)
◯: Peel force is 1.0 (N / 25 mm) or more (good)
Δ: Peeling force is 0.5 (N / 25 mm) or more and less than 1.0 (N / 25 mm) (usable)
X: Peeling force is less than 0.5 (N / 25 mm) (cannot be used)

[Examples 2 to 26, Comparative Examples 1 to 5]
An active energy ray-polymerizable adhesive and a laminate were respectively produced in the same manner as in Example 1 except that the materials and compositions shown in Tables 1 and 2 were changed, and the viscosity, viscosity with time, viscosity change rate, room temperature adhesive strength, The high temperature adhesion and low temperature adhesion were evaluated. The evaluation results are shown in Tables 1 and 2.
In addition, Examples 18 and 19 in Table 1 and Examples 23 to 26 are meant as reference examples.

The materials used in the examples and their abbreviations are shown below.
<Compound (A)>
MEDOL-10: (2-methyl-2-ethyl-1,3-dioxolan-4-yl) methyl acrylate, manufactured by Osaka Organic Chemical Industry Co., Ltd., trade name MEDOL-10.
Biscoat 200: 5-ethyl-1,3-dioxan-5-ylmethyl acrylate, manufactured by Osaka Organic Chemical Industry, trade name Biscoat # 200

<Compound (C)>
FA511AS: Dicyclopentenyl acrylate manufactured by Hitachi Chemical Co., Ltd. under the trade name Funkryl FA511AS
IBXA: Isobornyl acrylate, manufactured by Osaka Organic Chemical Industry, trade name IBXA
A-DCP: tricyclodecane dimethanol diacrylate Shin Nakamura Chemical Co., Ltd. product name NK ester A-DCP
BPE-80N: ethoxylated bisphenol A dimethacrylate Shin Nakamura Chemical Co., Ltd. product name NK ester BPE-80N

<Compound (D1)>
UV3000B: Urethane acrylate oligomer, manufactured by Nippon Synthetic Chemical Industry Co., Ltd., product name Shikko UV3000B
EBECRYL210: Urethane acrylate oligomer, manufactured by Daicel Ornex, product name EBECRYL210
<Compound (D2)>
EBECRYL525: Polyester acrylate oligomer (containing 40% by mass of tripropylene glycol diacrylate), manufactured by Daicel Ornex Co., trade name EBECRYL525
EBECRYL884: Polyester acrylate oligomer, manufactured by Daicel Ornex Co., trade name EBECRYL884
<Compound (D3)>
KAYARAD R-9485: Epoxy acrylate oligomer, manufactured by Nippon Kayaku Co., Ltd., trade name KAYARAD R-9485.
BAEM-100: Mepoxymethacrylate oligomer, manufactured by KSM, trade name BAEM-100.

<Compound (E)>
THFA: tetrahydrofurfuryl acrylate manufactured by Osaka Organic Chemical Industry Co., Ltd., trade name Biscoat # 150
<Compound (F)>
2021P: 3,4-epoxycyclohexylmethyl (3,4-epoxy) cyclohexylcarboxylate, manufactured by Daicel, trade name Celoxide 2021P
EX212L: 1,6-hexanediol diglycidyl ether (low chlorine grade), manufactured by Nagase Chemitex, trade name Denacol EX212L
<Compound (G)>
Irgacure 184: 1-hydroxy-cyclohexyl-phenyl-ketone, manufactured by BASF, brand name Irgacure 184
CPI-100P: Active energy ray cationic polymerization initiator, manufactured by San-Apro Co., Ltd., trade name CPI-110P

  The active energy ray-polymerizable adhesive of the present invention is excellent in storage stability, and the laminates (Examples 1-26) using the active energy ray-polymerizable adhesive of the present invention are the laminates of Comparative Examples 1-5. It became clear that the adhesive strength at room temperature, the adhesive strength at high temperature, and the adhesive strength at low temperature were superior to those of

Claims (4)

Molecular weight is rather smaller than 500, mono (meth) acrylate monomers having a heterocycle oxygen containing two or more as atoms constituting the ring (A) (excluding acryloyl morpholine),
Molecular weight is rather smaller than 500, having a hydroxyl group (meth) acrylate monomer (B) (except having a heterocyclic ring of (meth) acrylate monomer (A)), and molecular weight is rather smaller than 500, other than the heterocyclic ring Including a (meth) acrylate monomer (C) (excluding the mono (meth) acrylate monomer (A) and the (meth) acrylate monomer (B)),
The total amount of the (meth) acrylate monomers (A), (B), and (C) is 70% by mass or more, and the (meth) acrylate monomer (A) is 5 to 70% by mass, the (meth) acrylate. An optical active energy ray-polymerizable adhesive containing the monomer (B) in an amount of 20 to 80% by mass and the (meth) acrylate monomer (C) in an amount of 5 to 50% by mass.   Furthermore, an oligomer selected from the group consisting of a polyurethane-based oligomer (D1) having a (meth) acryloyl group, a polyester-based oligomer (D2) having a (meth) acryloyl group, and an epoxy oligomer (D3) having a (meth) acryloyl group. The active energy ray-polymerizable adhesive for optics according to claim 1, containing one or more of The optical active energy according to claim 1 or 2, wherein the (meth) acrylate monomer (B) is at least one or more (meth) acrylate monomer selected from the group consisting of the following (B1) to (B3). Linear polymerizable adhesive.
The (meth) acrylate monomer (B1) is 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, 8-hydroxyoctyl (meth) acrylate, 12-hydroxylauryl (meth) acrylate, ethyl (meth) acrylate-α- (hydroxymethyl), glycidyl (meth) acrylate Laurate, cyclohexanedimethanol mono (meth) acrylate, cyclohexanediethanol mono (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, and 2- (meth) acryloyloxyethyl-2-hydroxyethylphthalic acid. Selected from the Ranaru group.
The (meth) acrylate monomer (B2) is a (meth) acrylic acid ester having a hydroxyl group added to the molecular end by ring-opening addition of ε-caprolactone to the (meth) acrylate monomer (B1).
The (meth) acrylate monomer (B3) is an alkylene oxide-added (meth) acrylic acid ester obtained by repeatedly adding alkylene oxide to the (meth) acrylate monomer (B1).   An optical laminate comprising a first base material, a resin layer that is a cured product of the optical active energy ray-polymerizable adhesive according to any one of claims 1 to 3, and a second base material. .